Science News & Views

UCR scientists identify pomegranate juice components that could stop cancer from spreading.

2010-12-13T07:14:00.000-08:00

Riverside- California One of the deadly complications of cancer cells is their tendency to get detached from the primary site and spread rapidly through the lymphatic system. Such detached cells multiply independently at different sites. In such instances the physicians have to use chemotherapy to kill the malignant cells, a treatment which has side effects.
Researchers at the University of California, Riverside have identified components in pomegranate juice that both inhibit the movement of cancer cells and weaken their attraction to a chemical signal that promotes the metastasis of prostate cancer to the bone. The research could lead to new therapies for preventing cancer metastasis.

Manuela Martins-Green, a professor of cell biology, presented the research today (Dec. 12, 2010) at the 50th annual meeting of the American Society for Cell Biology taking place in Philadelphia.
Prostate cancer is not curable and is the second-leading cause of cancer-related deaths in men in the United States. If prostate cancer recurs after surgery and/or radiotherapy , usually the next treatment is the suppression of the male hormone testosterone, which inhibits the growth of the cancer cells because they need this hormone to grow. Cancer cells are too clever. Over time, they develop ways to resist hormone suppression therapies, become very aggressive, and metastasize to the bone marrow, lungs, and lymph nodes, usually resulting in the patient's death.
The Martins-Green lab applied pomegranate juice on laboratory-cultured prostate cancer cells that were resistant to testosterone (the more resistant a cancer cell is to testosterone, the more prone it is to metastasizing).

The researchers – Martins-Green, graduate student Lei Wang and undergraduate students Andre Alcon and Jeffrey Ho – found that the pomegranate juice-treated tumor cells that had not died with the treatment showed increased cell adhesion (meaning fewer cells breaking away) and decreased cell migration.
Next, the researchers identified the active groups of ingredients such as phenylpropanoids, hydrobenzoic acids, flavones and conjugated fatty acids in pomegranate juice that had a molecular impact on cell adhesion and migration in metastatic prostate cancer cells.
"Having identified them, we can now modify cancer-inhibiting components in pomegranate juice to improve their functions and make them more effective in preventing prostate cancer metastasis, leading to more effective drug therapies," Martins-Green said. "Because the genes and proteins involved in the movement of prostate cancer cells are essentially the same as those involved in the movement of other types of cancer cells, the same modified components of the juice could have a much broader impact in cancer treatment."
Martins-Green explained that an important protein produced in the bone marrow causes the cancer cells to move to the bone where they can then form new tumors.
"We show that pomegranate juice markedly inhibits the function of this protein, and thus this juice has the potential of preventing metastasis of the prostate cancer cells to the bone," Martins-Green said.
Next, her lab plans to do additional tests in an in vivo model for prostate cancer metastasis to determine whether the same cancer-inhibiting components that work in cultured cells can prevent metastasis without side effects.
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Five-Year Study Shows ‘Healthy Worker Effect’ At US Paducah Plant

2010-08-11T17:21:00.001-07:00

Five-Year Study Shows ‘Healthy Worker Effect’ At US Paducah Plant

A five-year study into the causes of deaths of workers at
the Paducah Gaseous Diffusion Plant (PGDP) in the US state of Kentucky
shows significantly lower death rates from all causes and cancer in general
when compared to the overall US population.

However, death from lymphatic and bone marrow cancers such as leukemia or
multiple myeloma were slightly above national rates.This result is similar to those reported earlier.

The University of Louisville’s School of Public
Health and Information Sciences, the University of Cincinnati and the
University of Kentucky conducted the study.

Researchers compiled data from employees’ work history, demographic
records and records from the US Social Security Administration, the
National Death Index and individual state departments. They found complete
data for 6,759 of the 6,820 employees who worked at the plant for at least
30 days between September 1952 and December 2009.

Out of those 6,759 people, the researchers identified 1,638 deaths. This
is fewer than the 2,253 deaths that would have been expected in the general
public.

They also found that 461 of the deaths were attributed to cancer, much less than 592, to be expected from comparable sized group in the general public.

Researchers concluded that overall mortality and cancer rates were lower
than the reference population, reflecting a “strong healthy worker effect”.
This effect is well known by epidemiologists. Regular medical check-ups and
better early care for health problems among workers in industries such as
nuclear result in generally better health for these workers compared to the
average population.

PGDP is the only gas-diffusion enrichment facility still operating in the
US. Two other plants existed at Oak Ridge, Tennessee and Piketon, Ohio.
Studies had been conducted for these plants, but none had yet been
conducted for PGDP.

David Tollerud, professor of environmental and occupational health
sciences at the University of Louisville’s School of Public Health and
Information Sciences, said the study addressed lingering concerns about the
health of workers at the plant.

He said: “It is important for occupational health and public health
research to attempt to answer pressing concerns of impacted populations,
and we were able to report that we didn't find unexpectedly high rates of
disease in this workforce.”

Security workers had higher overall death rates than other employees,
while chemical operators had higher death rates from leukemia and multiple
myeloma than the rest of the workers.

The increased number of lymphatic and bone marrow cancer deaths is
consistent with what researchers expected, Mr Tollerud said. “Based on
other studies, these forms of cancer have been linked to low levels of
radiation exposure.”

The Paducah plant was commissioned in 1952 as part of a US government
programme to produce enriched uranium to fuel military reactors and nuclear
weapons.

The plant’s mission changed in the 1960s from enriching uranium for
nuclear weapons to enriching uranium for use in commercial nuclear reactors
to generate electricity. It is owned by the US. Department of Energy and is
leased and operated by the United States Enrichment Corporation, a
subsidiary of USEC Inc.

The study, titled ‘Mortality among PGDP workers,’ was published in the
July 2010 edition of the Journal of Occupational and Environmental Medicine
(www.joem.org).

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FDA Gives Green Light to First Embryonic Stem Cell Trial in Humans

2010-08-09T06:21:00.000-07:00

On July 30, 2010, Geron Corporation , a company developing biopharmaceuticals to treat cancer and chronic degenerative diseases, including spinal cord injury, heart failure and diabetes announced that the U.S. Food and Drug Administration (FDA) has notified them that the clinical hold placed on its Investigational New Drug (IND) application has been lifted and the company's Phase I clinical trial of GRNOPC1 in patients with acute spinal cord injury may proceed.
It is the first embryonic stem cell clinical trial approved by the FDA.
The Phase I multi-center trial may hopefully establish the safety of GRNOPC1 in patients with "complete" American Spinal Injury Association (ASIA) Impairment Scale grade A sub-acute thoracic spinal cord injuries.
"We are pleased with the FDA's decision to allow our planned clinical trial of GRNOPC1 in spinal cord injury to proceed," said Thomas B. Okarma, Ph.D., M.D., Geron's president and CEO. "Our goals for the application of GRNOPC1 in subacute spinal cord injury are unchanged - to achieve restoration of spinal cord function by the injection of hESC-derived oligodendrocyte progenitor cells directly into the lesion site of the patient's injured spinal cord. Additionally, we are now formally exploring the utility of GRNOPC1 in other degenerative CNS disorders including Alzheimer's, multiple sclerosis and Canavan disease."
FDA placed a hold on the trial following results from a single preclinical animal study in which Geron observed a higher frequency of small cysts within the injury site in the spinal cord of animals injected with GRNOPC1 than had previously been noted in numerous foregoing studies.
In response to those results, Geron developed new markers and assays as additional release specifications for GRNOPC1. The company completed an additional confirmatory preclinical animal study to test the new markers and assays, and subsequently submitted a request to the FDA for the clinical hold to be lifted.
GRNOPC1, Geron's lead hESC-based therapeutic candidate, contains hESC-derived oligodendrocyte progenitor cells that have demonstrated remyelinating and nerve growth stimulating properties leading to restoration of function in animal models of acute spinal cord injury (Journal of Neuroscience, Vol. 25, 2005).
"The neurosurgical community is ready to begin the clinical testing of this new approach to treating devastating spinal cord injury," said Richard Fessler, M.D., Ph.D., professor of neurological surgery at the Feinberg School of Medicine at Northwestern University. "We know that demyelination is central to the pathology of the injury, and its reversal by means of injecting oligodendrocyte progenitor cells would be revolutionary for the field. If found to be safe and effective, the therapy would provide a viable treatment option for thousands of patients who suffer severe spinal cord injuries each year."
The GRNOPC1 Clinical Program
Patients eligible for the Phase I trial must have documented evidence of functionally complete spinal cord injury with a neurological level of T3 to T10 spinal segments and agree to have GRNOPC1 injected into the lesion sites between seven and 14 days after injury.
Although the primary endpoint of the trial is safety, the protocol includes secondary endpoints to assess efficacy, such as improved neuromuscular control or sensation in the trunk or lower extremities. Once safety in this patient population has been established, Geron plans to seek FDA approval to extend the study to increase the dose of GRNOPC1, enroll subjects with complete cervical injuries and expand the trial to include patients with severe incomplete (ASIA Impairment Scale grade B or C) injuries to enable access to the therapy for as broad a population of severe spinal cord-injured patients as is medically appropriate.
Geron has selected up to seven U.S. medical centers as candidates to participate in this study and in planned protocol extensions. The sites will be identified as they come online and are ready to enroll subjects into the study.
Other Potential Neurological Indications for GRNOPC1
Geron claimed that in addition to spinal cord injury, GRNOPC1 may have therapeutic utility for other central nervous system indications. It has established many collaborations with academic groups to test GRNOPC1 in selected animal models of human disease for which there is a strong rationale for the approach.
The company listed other areas of work in which it is actively involved.
Alzheimer's Disease: Alzheimer's disease is a progressive, fatal, degenerative disorder that attacks the neurons in the brain, resulting in loss of memory, cognitive function such as reasoning and language, and behavioral changes. According to the Alzheimer's Association an estimated five million people in the United States have Alzheimer's disease. GRNOPC1 is being evaluated in animal models of Alzheimer's disease in collaboration with Professor Frank M. LaFerla, Director of the Institute for Memory Impairments and Neurological Disorders (UCI MIND) at the University of California, Irvine.
Multiple Sclerosis (MS): MS is an autoimmune disease that causes demyelination of nerve axons in the brain and spinal cord often progressing to physical and cognitive disability. There is currently no known cure for the disease. According to the National Multiple Sclerosis Society there are about 400,000 people in the United States with MS. GRNOPC1 is being tested in a non-human primate model of MS in collaboration with Professor Jeffery D. Kocsis of the Departments of Neurology and Neurobiology at Yale University School of Medicine and the Department of Veterans Affairs.
Canavan Disease: Canavan disease is a fatal neurological disorder that belongs to a group of genetic disorders called leukodystrophies, characterized by the abnormal development or degeneration of myelin. Symptoms of Canavan disease present in the first six months of life and death usually occurs at 3 - 10 years of age. GRNOPC1 is being tested in a rodent model of Canavan disease in collaboration with Dr. Paola Leone, Director of the Cell and Gene Therapy Center, at the University of Medicine and Dentistry of New Jersey.

Genes from sweet pepper can fortify African banana against devastating wilt disease

2010-08-07T05:46:00.000-07:00

Genes from sweet pepper can fortify African banana against devastating wilt disease

The BXW or Banana Xanthomonas Wilt is the tongue twisting name of a disease which wipes out banana in vast areas in the Great lake region of Africa. It costs about half a billion dollars worth of damage every year across East and Central Africa. The leaves of affected crops turn yellow and then wilt, and the fruit ripens unevenly and prematurely. Eventually the entire plant withers and rots.

Crop scientists announced today the successful transfer of green pepper genes to bananas, conferring on the popular fruit the means to resist the disease.
Dr. Leena Tripathi, a biotechnologist with International Institute of Tropical Agriculture (IITA) and lead author of the paper, said there is still a long way to go before the transgenic bananas find their way onto farmers' fields, but she called the breakthrough "a significant step in the fight against the deadly banana disease."
The transformed bananas, newly-infused with one of two proteins from the green pepper, have shown strong resistance to Xanthomonas wilt in the laboratory and in screen houses. The researchers are poised to begin confined field trials in Uganda soon.
Some of the findings on the protective impact of the two proteins—plant ferredoxin-like amphipathic protein (Pflp) and hypersensitive response-assisting protein (Hrap)—were published recently in the journal Molecular Plant Pathology.
"The Hrap and Pflp genes work by rapidly killing the cells that come into contact with the disease-spreading bacteria, essentially blocking it from spreading any further," Tripathi said. "Hopefully, this will boost the arsenal available to fight BXW and help save millions of farmers' livelihoods in the Great Lakes region."
The novel green pepper proteins that give crops enhanced resistance against deadly pathogens can also provide effective control against other BXW-like bacterial diseases in other parts of the world. Tripathi adds that the mechanism known as Hypersensitivity Response also activates the defenses of surrounding and even distant uninfected banana plants leading to a systemic acquired resistance.
Scientists from the IITA and the National Agricultural Research Organisation (NARO) of Uganda, in partnership with African Agricultural Technology Foundation (AATF), will soon begin evaluating these promising new banana lines under confined field trials. The Ugandan National Biosafety Committee recently approved the tests, which can now move forward.
The genes used in this research were acquired under an agreement from the Academia Sinica in Taiwan.
The highly destructive BXW affects all varieties, including the East African Highland bananas and exotic dessert, roasting, and beer bananas. The crop is also under threat from another deadly disease, the banana bunchy top.
Dr. Tripathi says that there are presently no commercial chemicals, biocontrol agents or resistant varieties that can control the spread of BXW. "Even if a source of resistance is identified today," Tripathi said, "developing a truly resistant banana through conventional breeding would be extremely difficult and would take years, even decades, given the crop's sterility and its long gestation period."
BXW was first reported in Ethiopia 40 years ago on Ensete, a crop relative of banana, before it moved on to bananas. Outside of Ethiopia, it was first reported in Uganda in 2001, then rapidly spread to the Democratic Republic of Congo, Rwanda, Kenya, Tanzania, and Burundi, leaving behind a trail of destruction in Africa's largest banana producing and consuming region.
BXW can be managed by de-budding the banana plant (removing the male bud as soon as the last hand of the female bunch is revealed) and sterilizing farm implements used. However, the adoption of these practices has been inconsistent at best as farmers believe that de-budding affects the quality of the fruit and sterilizing farm tools is a tedious task.
The research to fortify bananas against BXW using genes from sweet pepper was initiated in 2007.

Why MRC did not fund IVF research that led to Louise Brown, the first test tube baby?

2010-07-25T18:29:00.001-07:00

Why MRC didn't fund IVF research that led to the birth of the world's first test tube baby
Louise Brown, the first “test tube baby” was born on July 25, 1978. Since then, an estimated 4.3 million babies have been born worldwide with the help of a range of fertility treatments.
The UK Medical Research Council refused to fund the research on In Vitro Fertilization which led to the breakthrough. Finally, the project funds came from a private trust
For the first time, the reasons for MRC’s denial for funding, was disclosed in a paper published in Europe's leading reproductive medicine journal Human Reproduction.
The authors of the new research, led by Martin Johnson, Professor of Reproductive Sciences at the University of Cambridge, and funded by the Wellcome Trust, write: "The failure of Edwards' and Steptoe's application for long-term support was not simply due to widespread establishment hostility to IVF. It failed, we argue for more complex reasons".
They listed the following reasons:
• A strategic error by Edwards and Steptoe when they declined an invitation from the MRC to join a new, directly funded Clinical Research Centre at Northwick Park Hospital, Harrow. They preferred to ask for long-term grant support at the University of Cambridge, but this meant they had to compete for funding with all the other research projects bidding for MRC support. This was also difficult for Cambridge, which lacked the back-up of an academic Department of Obstetrics and Gynaecology at that time.
• Most of the MRC referees who were consulted on the proposal considered, in line with government policy, that it was more important to limit fertility and the growth of Britain's population than to treat infertility. Treating infertility was seen as experimental research rather than as therapeutic.
• Concerns about embryo quality (would babies be born with severe abnormalities?) and patient safety made the referees doubt the wisdom of funding embryo transfer without conducting studies in primates first.
• Edwards' and Steptoe's high profile in the media antagonised the referees who strongly disapproved of this method of public discussion of the science and ethics of treating infertility.
Additionally, MRC saw Edwards and Steptoe as not being part of the "medical establishment". "Steptoe came from a minor northern hospital, while Edwards, though from Cambridge, was neither medically qualified nor yet a professor." Prof Johnson and his colleagues clarified..
Edwards had a PhD in developmental genetics from the Institute of Animal Genetics at the University of Edinburgh, then the leading UK centre in the field.
According to Professor Johnson the MRC's negative decision on funding of IVF, and their public defence of this decision, had major consequences for Edwards and Steptoe and set MRC policy on IVF research funding for the next eight years.
MRC reversed their decision after the birth of two healthy babies from seven IVF pregnancies. The MRC announced a change of policy in its 1978/79 Annual Report. Thereafter, MRC became a strong and major supporter of research on human IVF and human embryos; although not on follow-up of IVF pregnancies.
Prof Johnson and his colleagues, Sarah Franklin, Matthew Cottingham and Nick Hopwood, spent three years studying the MRC records at the National Archives at Kew in Surrey, and also documents from the Royal College of Obstetricians and Gynaecologists, Addenbrooke's Hospital, Cambridgeshire County Council and Cambridge University Library.
Bob Edwards' wife, Ruth, gave them access to his private papers, and the researchers also interviewed many of the key players involved in the MRC's decision in 1971 not to fund the research.
In an accompanying editorial, Professor John Biggers from Harvard Medical School (USA), writes: "By taking us back 40 years, the authors have demonstrated the importance of understanding a decision in light of the culture and circumstances at the time the decision was made. Although the grant was rejected, Edwards' and Steptoe's visions and persistence have benefited an enormous number of infertile people, both male and female."
The researchers observations are very interesting. According to Prof Johnson the story of the MRC's non-funding of IVF belies the cliché that science 'races ahead' of society. Similarly, the standard view, that ethical consideration of bioscience and biomedicine can only ever be reactive, is contradicted by the evidence of extensive ethical debate surrounding the prehistory of clinical IVF – most of it actively stimulated by Edwards himself.
The developments preceding the great breakthrough revealed a few other facts. Although attitudes to medical scientists in the media have changed significantly since the 1970s, scientists and clinicians engaged in high-profile work still face a dilemma. If they encourage public discussion of their work – which they may see as both necessary to securing support and desirable to ensure full ethical debate – must they inevitably weaken their standing among their peers?
The researchers claimed that their case study questions the myth of two courageous mavericks pitted against a conservative establishment. “This myth does capture important elements of truth: Edwards and Steptoe were outsiders and did pioneer—against prevailing wisdom—new ideas, therapies, values, public discourses and ethical thinking. But the process of decision-making was more complex than the myth allows. Our research provides a fuller understanding of what happened at the birth of the IVF revolution." They noted
Prof Johnson believes that today the decision-making processes involved in awarding funding for projects are more open and transparent, with discussion in the wider community and in the media actively welcomed, as was the case with the two Human Fertilisation and Embryology Acts in 1990 and 2008.
"A continuing problem, however, is more to do with the fact that there are some very fashionable topics that can create a buzz and attract huge research interest and funding, sometimes in disproportionate amounts; then it was fertility limitation, more recently genome sequencing would be an example. This can leave other Cinderella topics languishing in the ashes, with little financial support, even though they might well play an equally, if not more, important role in patient welfare."

WSU researchers use super-high pressures to create super battery

2010-07-05T05:32:00.000-07:00

Public release date: 4-Jul-2010

Contact: Choong-Shik Yoo
csyoo@wsu.edu
925-640-7549
Washington State University

WSU researchers use super-high pressures to create super battery
'Most condensed form of energy storage outside of nuclear energy'

PULLMAN, Wash.—The world's biggest Roman candle has got nothing on this.

Using super-high pressures similar to those found deep in the Earth or on a giant planet, Washington State University researchers have created a compact, never-before-seen material capable of storing vast amounts of energy.

"If you think about it, it is the most condensed form of energy storage outside of nuclear energy," says Choong-Shik Yoo, a WSU chemistry professor and lead author of results published in the journal Nature Chemistry.

The research is basic science, but Yoo says it shows it is possible to store mechanical energy into the chemical energy of a material with such strong chemical bonds. Possible future applications include creating a new class of energetic materials or fuels, an energy storage device, super-oxidizing materials for destroying chemical and biological agents, and high-temperature superconductors.

The researchers created the material on the Pullman campus in a diamond anvil cell, a small, two-inch by three-inch-diameter device capable of producing extremely high pressures in a small space. The cell contained xenon difluoride (XeF2), a white crystal used to etch silicon conductors, squeezed between two small diamond anvils.

At normal atmospheric pressure, the material's molecules stay relatively far apart from each other. But as researchers increased the pressure inside the chamber, the material became a two-dimensional graphite-like semiconductor. The researchers eventually increased the pressure to more than a million atmospheres, comparable to what would be found halfway to the center of the earth. All this "squeezing," as Yoo calls it, forced the molecules to make tightly bound three-dimensional metallic "network structures." In the process, the huge amount of mechanical energy of compression was stored as chemical energy in the molecules' bonds.

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Financial support for the research came from the U.S. Department of Defense's Defense Threat Reduction Agency and the National Science Foundation.

Using carbon nanotubes in lithium batteries can dramatically improve energy capacity

2010-06-21T02:05:00.000-07:00

Public release date: 20-Jun-2010

Contact: Jennifer Hirsch
jfhirsch@mit.edu
617-253-1682
Massachusetts Institute of Technology
Using carbon nanotubes in lithium batteries can dramatically improve energy capacity
New method produced up to ten fold increase in power

CAMBRIDGE, Mass. -- Batteries might gain a boost in power capacity as a result of a new finding from researchers at MIT. They found that using carbon nanotubes for one of the battery's electrodes produced a significant increase — up to tenfold — in the amount of power it could deliver from a given weight of material, compared to a conventional lithium-ion battery. Such electrodes might find applications in small portable devices, and with further research might also lead to improved batteries for larger, more power-hungry applications.

To produce the powerful new electrode material, the team used a layer-by-layer fabrication method, in which a base material is alternately dipped in solutions containing carbon nanotubes that have been treated with simple organic compounds that give them either a positive or negative net charge. When these layers are alternated on a surface, they bond tightly together because of the complementary charges, making a stable and durable film.

The findings, by a team led by Associate Professor of Mechanical Engineering and Materials Science and Engineering Yang Shao-Horn, in collaboration with Bayer Chair Professor of Chemical Engineering Paula Hammond, are reported in a paper published June 20 in the journal Nature Nanotechnology. The lead authors are chemical engineering student Seung Woo Lee PhD '10 and postdoctoral researcher Naoaki Yabuuchi.

Batteries, such as the lithium-ion batteries widely used in portable electronics, are made up of three basic components: two electrodes (called the anode, or negative electrode, and the cathode, or positive electrode) separated by an electrolyte, an electrically conductive material through which charged particles, or ions, can move easily. When these batteries are in use, positively charged lithium ions travel across the electrolyte to the cathode, producing an electric current; when they are recharged, an external current causes these ions to move the opposite way, so they become embedded in the spaces in the porous material of the anode.

In the new battery electrode, carbon nanotubes — a form of pure carbon in which sheets of carbon atoms are rolled up into tiny tubes — "self-assemble" into a tightly bound structure that is porous at the nanometer scale (billionths of a meter). In addition, the carbon nanotubes have many oxygen groups on their surfaces, which can store a large number of lithium ions; this enables carbon nanotubes for the first time to serve as the positive electrode in lithium batteries, instead of just the negative electrode.

This "electrostatic self-assembly" process is important, Hammond explains, because ordinarily carbon nanotubes on a surface tend to clump together in bundles, leaving fewer exposed surfaces to undergo reactions. By incorporating organic molecules on the nanotubes, they assemble in a way that "has a high degree of porosity while having a great number of nanotubes present," she says.

Lithium batteries with the new material demonstrate some of the advantages of both capacitors, which can produce very high power outputs in short bursts, and lithium batteries, which can provide lower power steadily for long periods, Lee says. The energy output for a given weight of this new electrode material was shown to be five times greater than for conventional capacitors, and the total power delivery rate was 10 times that of lithium-ion batteries, the team says. This performance can be attributed to good conduction of ions and electrons in the electrode, and efficient lithium storage on the surface of the nanotubes.

In addition to their high power output, the carbon nanotube electrodes showed very good stability over time. After 1,000 cycles of charging and discharging a test battery, there was no detectable change in the material's performance.

The electrodes the team produced had thicknesses up to a few microns, and the improvements in energy delivery only were seen at high-power output levels. In future work, the team aims to produce thicker electrodes and extend the improved performance to low-power outputs as well, they say. In its present form, the material might have applications for small, portable electronic devices, says Shao-Horn, but if the reported high power capability were demonstrated in a much thicker form — with thicknesses of hundreds of microns rather than just a few — it might eventually be suitable for other applications such as hybrid cars.

While the electrode material was produced by alternately dipping a substrate into two different solutions — a relatively time-consuming process — Hammond suggests that the process could be modified by instead spraying the alternate layers onto a moving ribbon of material, a technique now being developed in her lab. This could eventually open the possibility of a continuous manufacturing process that could be scaled up to high volumes for commercial production, and could also be used to produce thicker electrodes with a greater power capacity. "There isn't a real limit" on the potential thickness, Hammond says. "The only limit is the time it takes to make the layers," and the spraying technique can be up to 100 times faster than dipping, she says.

Lee says that while carbon nanotubes have been produced in limited quantities so far, a number of companies are currently gearing up for mass production of the material, which could help to make it a viable material for large-scale battery manufacturing.

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Source: "High-power lithium batteries from functionalized carbon nanotube electrodes." Seung Woo Lee, Naoaki Yabuuchi, Betar M. Gallant, Shuo Chen, Byeong-Su Kim, Paula T. Hammond, & Yang Shao-Horn. Nature Nanotechnology. 19 June 2010.

Stem cell charlatans

2010-06-19T01:44:00.000-07:00

In the latest British Medical Journal, Bob Roehr quoted Irving Weissman, the Stanford University researcher and president of the International Society for Stem Cell Research society as saying that the society launched a patient education website "to smoke out the charlatans" who prey upon desperately ill people and their families(BMJ 2010;340:c3271. This is a step in the right direction.

Dr Weissman, clarified that probably no other society has ever done this before. He was addressing the opening of their annual meeting on 16 June, in San Francisco.

Deveoloping countries are the preferred havens for the charlatans to prey on the gullible patients.

Bob Roehr argued that the problem is large and growing. He revealed that a recent web search identified more than 200 practitioners or clinics making claims for stem cell cures;, they thrive in developing countries obviously because regulatory oversight is weak in such countries. It is unbelievable that a clinic in China claimed to have treated over 8000 people, generating over $200m (£137m; 165m) in revenue.

It is difficult to arrest these activities. The scoiety felt that basic education about stem cells may help.The society’s new website, www.closerlookatstemcells.org, offers such material. According to the website a reputable clinical trial will have a body of scientific literature behind it; will be scrutinised by an independent review board; and will have the approval of the relevant national regulatory authorities. And it will not charge for participating in the trial.

The website allows a person to submit the name of a clinic for review. The society will then ask the clinic for documentation on ethical and regulatory review of the proposed treatment. That information will form a publicly available online database. It is not clear why a crook who is cashing on the misery of a victim should cooperate for such a review.

Bob Roehr quotes the case of a farmer who spent $80,000 for a stem cell "cure" for multiple sclerosis. An instance Dr Weissman found out while he gave a lecture in his home town, Great Falls, Montana, his hometown with a population of a little over 50 000. It is a pity that people mortgage their homes desperately seeking a cure where there is none.

The service offered by the society is laudable.Jeanne F Loring from the Scripps Research Institute a speker at th emeeting highlighted other issues. She pointed ouyt that patient testimonials are a hallmark of these operations. You will not see is any scientific evidence. There will be no guarantee that you will be helped by that treatment. Lastly,there are no guarantees that you won’t be harmed.

Clinics may use inappropriate treatment. According to the researcher, these clinics often use cord blood or placental cells, which may not be appropriate for the intended use. They may use cells derived from animals, or inject cell solutions that are tainted with other products.

Dr Loring suggested that if patients could procure a sample of the cells that are going to be injected, freeze them, and send them to her, she will analyse it for free and tell you what those stem cells are. This is indeed a generous offer.She can be contacted at jloring@scripps.edu

Regrettably, reporters of some popular newspapers in India unwittingly publicize the magic cures. They do not know the damage they are doing. They must resist the temptation; publish only those cures only if they appear in peer reviewed literature.

Highly efficient solar cells could result from quantum dot research

2010-06-18T00:49:00.000-07:00

Researchers from the University of Texas at Austin feel that they can enhance the limit of efficiency of currently available solar cells from 3o percent to 60 percent by converting the splar heat lost in the cells by a suitable design modification. They are confident that "there is no reason that we cannot be using solar energy 100 percent within 50 years."

The concept appears to be simple and straightforward; lot more work to advance the chemistry of semiconductor is needed to achieve the objective

K.S.Parthasarathy

EurekAlert! Public release date: 17-Jun-2010

Contact: Dr. Xiaoyang Zhu
zhu@cm.utexas.edu
512-471-9914
University of Texas at Austin
Highly efficient solar cells could result from quantum dot research

IMAGE: Xiaoyang Zhu and colleagues discovered that hot electrons can be transferred from photo-excited lead selenide nanocrystals to an electron conductor made of titanium dioxide. Their discovery points the way toward...
Click here for more information.

AUSTIN, Texas—Conventional solar cell efficiency could be increased from the current limit of 30 percent to more than 60 percent, suggests new research on semiconductor nanocrystals, or quantum dots, led by chemist Xiaoyang Zhu at The University of Texas at Austin.

Zhu and his colleagues report their results in this week's Science.

The scientists have discovered a method to capture the higher energy sunlight that is lost as heat in conventional solar cells.

The maximum efficiency of the silicon solar cell in use today is about 31 percent. That's because much of the energy from sunlight hitting a solar cell is too high to be turned into usable electricity. That energy, in the form of so-called "hot electrons," is lost as heat.

If the higher energy sunlight, or more specifically the hot electrons, could be captured, solar-to-electric power conversion efficiency could be increased theoretically to as high as 66 percent.

"There are a few steps needed to create what I call this 'ultimate solar cell,'" says Zhu, professor of chemistry and director of the Center for Materials Chemistry. "First, the cooling rate of hot electrons needs to be slowed down. Second, we need to be able to grab those hot electrons and use them quickly before they lose all of their energy."

Zhu says that semiconductor nanocrystals, or quantum dots, are promising for these purposes.

As for the first problem, a number of research groups have suggested that cooling of hot electrons can be slowed down in semiconductor nanocrystals. In a 2008 paper in Science, a research group from the University of Chicago showed this to be true unambiguously for colloidal semiconductor nanocrystals.

Zhu's team has now figured out the next critical step: how to take those electrons out.

They discovered that hot electrons can be transferred from photo-excited lead selenide nanocrystals to an electron conductor made of widely used titanium dioxide.

"If we take the hot electrons out, we can do work with them," says Zhu. "The demonstration of this hot electron transfer establishes that a highly efficient hot carrier solar cell is not just a theoretical concept, but an experimental possibility."

The researchers used quantum dots made of lead selenide, but Zhu says that their methods will work for quantum dots made of other materials, too.

He cautions that this is just one scientific step, and that more science and a lot of engineering need to be done before the world sees a 66 percent efficient solar cell.

In particular, there's a third piece of the science puzzle that Zhu is working on: connecting to an electrical conducting wire.

"If we take out electrons from the solar cell that are this fast, or hot, we also lose energy in the wire as heat," says Zhu. "Our next goal is to adjust the chemistry at the interface to the conducting wire so that we can minimize this additional energy loss. We want to capture most of the energy of sunlight. That's the ultimate solar cell.

"Fossil fuels come at a great environmental cost," says Zhu. "There is no reason that we cannot be using solar energy 100 percent within 50 years."

###

Funding for this research was provided by the U.S. Department of Energy. Coauthors include William Tisdale, Brooke Timp, David Norris and Eray Aydil from the University of Minnesota, and Kenrick Williams from The University of Texas at Austin.

Media contact: Lee Clippard, public affairs, 512-232-0675, lclippard@mail.utexas.edu

EurekAlert! ]

Nottingham research leads to blood test for early detection of cancer

2010-06-02T05:04:00.001-07:00

Public release date: 1-Jun-2010

Contact: Lindsay Brooke
lindsay.brooke@nottingham.ac.uk
44-115-951-5751
University of Nottingham
Nottingham research leads to blood test for early detection of cancer

The University of Nottingham spin-out company, Oncimmune Ltd, has developed a ground breaking blood test which will aid the detection of cancer as much as five years earlier than current testing methods such as mammography and CT scans. Physicians will know the result of their patient's test within one week of sending in a blood sample to Oncimmune.

Oncimmune has developed a new technique which replicates the cancer proteins that trigger the body's response to the disease and robotic technology to measure this response. This new technology (immuno-biomarkers) provides a significant advance in how early a cancer may be detected and is likely to change the current paradigm of diagnosis and treatment for most solid cancers such as lung, breast, ovarian, colon and prostate.

Based on the early work of John Robertson, a world renowned breast cancer specialist and Professor of Surgery in The University of Nottingham's Faculty of Medicine and Health Sciences, Oncimmune has successfully transferred this science into a reproducible commercial test. The test for lung cancer, EarlyCDT-Lung™ will be launched nationally in the USA this month followed by a launch in the UK early next year.

Geoffrey Hamilton-Fairley, Executive Chairman of Oncimmune, said: "We believe this test, along with the others we will launch in the next few years, will lead to a better prognosis for a significant number of cancer sufferers."

Initial research results were derived using blood samples from patients with breast cancer and a group of high risk women attending for annual mammography — which Professor Robertson had prospectively collected in Nottingham. All samples were obtained with fully informed consent as part of a study which had received approval from the appropriate ethics committee. In addition to identifying the signal in the blood of a percentage of women when they developed breast cancer the results also showed that the signal could be detected in some of the high-risk patients who had given blood samples for a number of years during their annual check up and before they were subsequently diagnosed with cancer. When these samples were run retrospectively by Professor Robertson he showed that the prototype assay test could have detected over half of these cancers up to four years before they were actually diagnosed. The work on lung cancer followed through a European Union grant which involved both The University of Nottingham and Oncimmune in a collaboration with a number of European partners.

Professor John Robertson said "I am very pleased that the initial exciting research data that we produced in the laboratories at The University of Nottingham a number of years ago have been translated by Oncimmune to the first of many tests that will help us identify cancer early. The support of the University at all levels, including past and present Vice-Chancellors, Deans of the Faculty of Medicine and Heads of School along with the University's Management Board has been essential. Some of the initial research work was supported by charitable funds and donations from patient groups. In the commercialisation of the technology there have been a number of individuals who have continued to believe in and financially support the goal of developing a blood test for the early detection of cancer without whom this technology would not have reached this milestone. It has been a long and at times very hard road in creating a robust commercial test and those involved have worked with exceptional diligence and tenacity and have given their unremitting support to achieve this."

A study involving researchers at the Mayo Clinic in the USA recorded similar results using blood samples from a study of CT scans to screen for lung cancer where antibodies were detected up to five years before the lung cancers were diagnosed. A number of other academic centres have reported similar results.

Oncimmune LTD was founded in 2003 to commercialise the technology developed in the laboratories of Professor Robertson. In 2006 the company set up a North American operation to validate and scale-up the test — trialling it on more than eight million assay "wells" from 80,000 patient samples.

The first early cancer detection test (EarlyCDT™) to launch will be the test for lung cancer (EarlyCDT-Lung) which has the potential to detect the early stages of lung cancer possibly up to five years before a tumour appears. The target population for this test are high-risk individuals such as long-term smokers and ex-smokers between the ages of 40 and 75. Additionally the test would be appropriate for people who have been exposed to other risk factors associated with the disease, for instance, environmental exposures such as radon, asbestos and extensive exposure to secondary smoke.

Under the guidance of Professor Robertson, The University of Nottingham has become a world leader in the field of autoimmunity in cancer. Using the technology developed by Oncimmune there is, for the first time, a reliable platform available for testing the autoimmune response to cancer and further research will allow validation of the test in other tumour areas such as lung, colon and ovarian cancer.

To support this, the University is to establish a Centre of Excellence for Autoimmunity in Cancer (CEAC) with Professor Robertson as the Director of Research. The new centre will foster collaborative research to: speed up the delivery of an autoantibody blood test for different types of cancer for clinical use; encourage other research in the area of autoimmunity in cancer; and continue the search for support technologies that have the potential to enhance the medical prognosis following a positive test result.

Professor David Greenaway, Vice-Chancellor of The University of Nottingham said: "The establishment of CEAC will provide state-of-the-art technologies to continue world leading research and development in the early detection of cancer using autoantibodies. The new centre will house a multi disciplinary research team working in partnership with international collaborators and Oncimmune. The research will provide additional test systems for the early diagnosis of a wide range of cancers which will have considerable impact within clinical medicine. The group's discovery science which has led to a novel set of biomarkers is providing new insights into the biology of cancer. Their basic, translational and clinical research is likely to contribute to a positive paradigm shift in our understanding of the early phases of cancer cell development as well as enhancement of the medical management of a wide range of cancer types."

Initially the test will be offered via primary care physicians and pulmonologists in the USA for high risk asymptomatic patients as well as patients who have indeterminate lung nodules. Oncimmune will bill private insurance companies as well as government-run Medicare Part B carriers on behalf of the patient.

###

More information can be found at: www.oncimmune.co.uk or www.oncimmune.com

Tracing bees using radiotransmitters

2010-05-27T05:33:00.000-07:00

Public release date: 26-May-2010
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Contact: Jen Laloup
jlaloup@plos.org
415-624-1220
Public Library of Science

Researchers learn about role of bees in tropical ecosystems using radio transmitters
A New York State Museum scientist is one of several researchers who have become the first to use tiny radio transmitters to track bees over long distances in a forest habitat, yielding new insight into the role of bees in tropical forest ecosystems. The bee study research conducted by Dr. Roland Kays, the Museum's curator of mammals, and the other scientists, was published in the online peer reviewed journal PLoS ONE on May 26th.

Armed with radio antennas, Kays and the other researchers worked at the Smithsonian Tropical Research Institute (STRI) in Panama City, Panama, to track unique signals from tiny transmitters glued to individual orchid bees. Although radar had been used to track bees in open areas, this is the first time it has been used in forested habitats. The research opens the door to future studies of bees in temperate forests, such as those in New York State.

Bees are important pollinators for plants worldwide. Pollination is critical for trees to make fruits and seeds, including domesticated edible fruits, as well as inedible species that are found in most New York State forest habitats. However, little is known about the movement of bees because they are so small and difficult to track.

Researchers, using helicopters, discovered that the orchid bees traveled surprisingly long distances, zipping through increasingly scarce patches of tropical forest as they moved pollen between rare flowers that grew miles apart.

"People disrupt plant pollination as they disturb and destroy tropical forests," said David Roubik, senior staff scientist at the Smithsonian. "Radio-tracking significantly improves our understanding of bees and the plants they pollinate. Now we can track orchid bees to get at the distances and spatial patterns involved—vital details which have completely eluded researchers in the past."

The researchers chose 17 iridescent blue-green orchid bees called Exaerete frontalis -- fairly common in the forest. They are larger than New York state honeybees but similar to some of the state's other large bumble bees. Roubik determined that Panama's orchid bees weigh only 0.6 grams without nectar in their stomachs.

"These bees easily carry a 300 mg radio transmitter glued on their backs," said Martin Wikelski, co-author of the research paper and director of the Max Planck Institute of Ornithology, professor at Princeton University and Smithsoian research associate. "By following the radio signals, we discovered that male orchid bees spent most of their time in small core areas, but could take off and visit areas farther away. One male even crossed over the shipping lanes in the Panama Canal, flying at least five kilometres, and returned a few days later."

In the past, researchers have struggled to determine the distances that bees travel, following individuals marked with paint between baits, or using radar, which doesn't work well when trees are in the way. "Carrying the transmitter could reduce the distance that the bees travel, but even if the flight distances we record are the minimum distances that these orchid bees can fly, they are impressive, long-distance movements," said Kays, who is also a research associate at STRI. "These data help to explain how orchids these bees pollinate can be so rare."

###
STRI, the U.S. Environmental Protection Agency, the New York State Museum and the National Geographic Society provided support for the bee study. Other co-authors are affiliated with the University of Arizona, Tucson; Cornell University and EcolSciences, Inc. In addition to hand tracking bees, Wikelski, Kays and colleagues have set up the Automated Radio Telemetry System on Barro Colorado Island (IS THIS IN PANAMA). The system is available to interested researchers and is capable of tracking up to 200 different animals, 24 hours a day, at any given time. A unit of the Smithsonian Institution, STRI furthers the understanding of tropical nature and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems. More information is available at www.stri.org.

Citation: Wikelski M, Moxley J, Eaton-Mordas A, Lo´ pez-Uribe MM, Holland R, et al. (2010) Large-Range Movements of Neotropical Orchid Bees Observed via Radio Telemetry. PLoS ONE 5(5): e10738. doi:10.1371/journal.pone.0010738

Funding: The study was supported by the US Environmental Protection Agency, New York State Museum, EcolSciences, Inc., Smithsonian Tropical Research Institute and the National Geographic Society. EcolSciences, as the only commercial company among the funding organizations, had a role in the analysis, decision to publish, and preparation of the manuscript through the involvment of David Moskowitz.

Competing Interests: David Moskowitz is employed by EcolSciences, who is a funder of this research. The employment of this author in a commercial company does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials, as detailed online in the guide for authors.

Contact:
Joanne Guilmette
Jguilmet@mail.nysed.gov
518/474-8730

PLEASE LINK TO THE SCIENTIFIC ARTICLE IN ONLINE VERSIONS OF YOUR REPORT (URL goes live after the embargo ends): http://dx.plos.org/10.1371/journal.pone.0010738

Disclaimer

This title and abstract release refers to upcoming articles in PLoS ONE. The releases have been provided by the article authors and/or journal staff. Any opinions expressed in these are the personal views of the contributors, and do not necessarily represent the views or policies of PLoS. PLoS expressly disclaims any and all warranties and liability in connection with the information found in the release and article and your use of such information.

About PLoS ONE

PLoS ONE is the first journal of primary research from all areas of science to employ a combination of peer review and post-publication rating and commenting, to maximize the impact of every report it publishes. PLoS ONE is published by the Public Library of Science (PLoS), the open-access publisher whose goal is to make the world's scientific and medical literature a public resource.

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New pathway to cheap insulin

2010-05-27T05:21:00.000-07:00

This paper deserves wide publicity as it reveals a cheaper method of making insulin

K.S.Parthasarathy

Public release date: 26-May-2010
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Contact: Bastian Dornbach
bastian.dornbach@helmholtz-hzi.de
49-053-161-811-407
Helmholtz Association of German Research Centres

New pathway to cheap insulin
Researchers from Helmholtz Centre in Braunschweig, Germany, publish new and more efficient method to manufacture insulin
More than eight million diabetics live in Germany. Diabetes is not restricted to our prosperous society and the highest growth rates often occur in countries with aspiring economies such as in Asia. Worldwide, more than 285 million people suffer from this illness; with 50 million diabetics, India is the country with the most people affected by this disease. In Europe, Germany shows the highest prevalence in the population with twelve percent. In a German-Indo collaboration, researchers from the Helmholtz-Centre for Infection Research (HZI) in Braunschweig, Germany have now developed a new method to cheaply produce insulin for the treatment of diabetes. The group's results have now been published in the open access online research magazine Microbial Cell Factories. With this, all information is freely accessible for everyone and is not subject to patent law.

"As we did last year with an alternative protocol for the development of a hepatitis B vaccine, we again decided to use this way and make our knowledge available for everybody," says Ursula Rinas from the HZI, who chairs the German side of the project. Thus, people can access "insider-information" that makes it possible to cheaply produce medicine which in return can be affordable to people in developing countries.

The researchers wanted to develop a new procedure to increase the yield of an insulin precursor from which the actual insulin can be obtained, and in this way reduce costs. They found the yeast Pichia pastoris and modified the cells so that they produce the building block for insulin while growing on a special medium. The results were highly gratifying: "With our procedure, Pichia pastoris delivers high yields – twice as much as known before", says Ursula Rinas. "Already with few cells it is possible to produce a lot of the insulin precursor."

In the early 1980s, insulin was the first recombinant product approved by the FDA for human application. Today, human insulin is produced as recombinant protein, using two major routes. One route involves the production of the insulin precursor using the bacterium Escherichia coli as expression host with complex subsequent isolation, solubilization and refolding procedures. The other route involves the well-known baker's yeast Saccharomyces cerevisiae. The advantage of the latter route lies in the secretion of a soluble insulin precursor into the culture supernatant, making it easier for isolation and chemical modification. The newly described method from Ursula Rinas and her group also uses this route. The isolation of the precursor from the culture supernatant is only followed by enzymatic finishing. Insulin produced with this new method can be used normally and is identical to human insulin. Currently, the researchers are working on a method to produce a vaccine against dengue fever using the same system as described here.

For most people in developing countries medicine is too expensive. The purchasing of insulin in those countries is often cost prohibitive. Another problem is patent law that makes it impossible to recreate medicine and sell it at low prices. Once a patent has expired, as is the case with insulin, the so called generic drugs can be produced cheaply. Unfortunately, emerging nations very often lack the insider knowledge to produce those generics.

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Original article: Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin. Gurramkonda C, Polez S, Skoko N, Adnan A, Gabel T, Chugh D, Swaminathan S, Khanna N, Tisminetzky S, Rinas U. Microb Cell Fact. 2010 May 12;9(1):31. [Epub ahead of print]

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Lowly termite, not the lion or elephant, may be the star of Africa's savanna

2010-05-26T04:25:00.000-07:00

It is an interesting observation. Termites are more important to the ecosystem that huge animals
K S Parthasarathy

Lowly termite, not the lion or elephant, may be the star of Africa's savanna

GAINESVILLE, Fla. --- The majestic animals most closely associated with the African savanna -- fierce lions, massive elephants, towering giraffes – may be relatively minor players when it comes to shaping the ecosystem.

The king of the savanna appears to be the termite, say ecologists who've found that these humble creatures contribute mightily to grassland productivity in central Kenya via a network of uniformly distributed colonies. Termite mounds greatly enhance plant and animal activity at the local level, while their even distribution over a larger area maximizes ecosystem-wide productivity.

The finding, published this week in the journal PLoS Biology, affirms a counterintuitive approach to population ecology: Often, it's the small things that matter most.

"One of the kind of typical things I think that people think about is, what drives a savanna in terms of its structure and function?" said Todd Palmer, one of the paper's authors and an assistant professor of biology at the University of Florida."We think about big animals, but these termites are having a massive impact on the system from below."

Said Robert M. Pringle, a research fellow at Harvard University and the lead author, "As (famed biologist) E.O. Wilson likes to point out, in many respects it's the little things that run the world."

Prior research on the Kenya dwarf gecko initially drew Pringle's attention to the peculiar role of grassy termite mounds, which in this part of Kenya are some 30 feet in diameter and spaced some 180 to 300 feet apart. Each mound teems with millions of termites, who build the mounds over the course of centuries.

After observing unexpectedly high numbers of lizards in the vicinity of mounds, Pringle, Palmer and their colleagues began to quantify ecological productivity relative to mound density. They found that each mound supported dense aggregations of flora and fauna: Plants grew more rapidly the closer they were to mounds, and animal populations and reproductive rates fell off appreciably with greater distance.

What was observed on the ground was even clearer in satellite imagery. Each mound – relatively inconspicuous on the Kenyan grassland – stood at the center of a burst of floral productivity. More important, these bursts were highly organized in relation to one another, evenly dispersed as if squares on a checkerboard. The result is an optimized network of plant and animal output closely tied to the ordered distribution of termite mounds.

"In essence, the highly regular spatial pattern of fertile mounds generated by termites actually increases overall levels of ecosystem production. And it does so in such a profound way," Palmer said. "Seen from above, the grid-work of termite mounds in the savanna is not just a pretty picture. The over-dispersion, or regular distribution of these termite mounds, plays an important role in elevating the services this ecosystem provides."

The mechanism through which termite activity is transformed into far-reaching effects on the ecosystem is a complex one. Pringle and Palmer suspect termites import coarse particles into the otherwise fine soil in the vicinity of their mounds. These coarser particles promote water infiltration of the soil, even as they discourage disruptive shrinking and swelling of topsoil in response to precipitation or drought.

The mounds also show elevated levels of nutrients such as phosphorus and nitrogen. All this beneficial soil alteration appears to directly and indirectly mold ecosystem services far beyond the immediate vicinity of the mound.

While further studies will explore the mechanism through which these spatial patterns of termite mounds emerge, Pringle and Palmer suggest that the present work has implications beyond the basic questions of ecology.

"Termites are typically viewed as pests, and as threats to agricultural and livestock production," Pringle said. "But productivity – of both wild and human-dominated landscapes – may be more intricately tied to the pattern-generating organisms of the larger natural landscape than is commonly understood."

###

Pringle and Palmer's co-authors on the PLoS Biology paper are Daniel F. Doak of the Mpala Research Centre and the University of Wyoming; Alison K. Brody of the Mpala Research Centre and the University of Vermont; and Rudy Jocqué of the Royal Museum for Central Africa in Tervuren, Belgium. Their work was supported by the Sherwood Family Foundation and the National Science Foundation.

Boston University reseachers develop faster, cheaper DNA sequencing method

2009-12-21T03:20:00.000-08:00

Researchers have found a new method of DNA sequencing which is claimed to be cheaper and faster than the method used so far.In the method developed by them one needs onle a smaller quantity of DNA thereby eliminating the expensive, time-consuming and error-prone step of DNA amplification.By boosting capture rates by a few orders of magnitude, and reducing the volume of the sample chamber the researchers reduced the number of DNA molecules required by a factor of 10,000 – from about 1 billion sample molecules to 100,000.

K.S.Parthasarathy

Public release date: 20-Dec-2009

Contact: Mike Seele
mseele@bu.edu
617-353-9766
Boston University College of Engineering
Boston University researchers develop faster, cheaper DNA sequencing method

IMAGE: A team of researchers led by Boston University biomedical engineer Amit Meller is using electrical fields to efficiently draw long strands of DNA through nanopore sensors, drastically reducing the number...
Click here for more information.

(BOSTON) EMBARGOED UNTIL 1 P.M. EST 12/20/09 -- Boston University biomedical engineers have devised a method for making future genome sequencing faster and cheaper by dramatically reducing the amount of DNA required, thus eliminating the expensive, time-consuming and error-prone step of DNA amplification.

In a study published in the Dec. 20 online edition of Nature Nanotechnology, a team led by Boston University Biomedical Engineering Associate Professor Amit Meller details pioneering work in detecting DNA molecules as they pass through silicon nanopores. The technique uses electrical fields to feed long strands of DNA through four-nanometer-wide pores, much like threading a needle. The method uses sensitive electrical current measurements to detect single DNA molecules as they pass through the nanopores.

"The current study shows that we can detect a much smaller amount of DNA sample than previously reported," said Meller. "When people start to implement genome sequencing or genome profiling using nanopores, they could use our nanopore capture approach to greatly reduce the number of copies used in those measurements."

Currently, genome sequencing utilizes DNA amplification to make billions of molecular copies in order to produce a sample large enough to be analyzed. In addition to the time and cost DNA amplification entails, some of the molecules – like photocopies of photocopies – come out less than perfect. Meller and his colleagues at BU, New York University and Bar-Ilan University in Israel have harnessed electrical fields surrounding the mouths of the nanopores to attract long, negatively charged strands of DNA and slide them through the nanopore where the DNA sequence can be detected. Since the DNA is drawn to the nanopores from a distance, far fewer copies of the molecule are needed.

Before creating this new method, the team had to develop an understanding of electro-physics at the nanoscale, where the rules that govern the larger world don't necessarily apply. They made a counterintuitive discovery: the longer the DNA strand, the more quickly it found the pore opening.

"That's really surprising," Meller said. "You'd expect that if you have a longer 'spaghetti,' then finding the end would be much harder. At the same time this discovery means that the nanopore system is optimized for the detection of long DNA strands -- tens of thousands basepairs, or even more. This could dramatically speed future genomic sequencing by allowing analysis of a long DNA strand in one swipe, rather than having to assemble results from many short snippets.

"DNA amplification technologies limit DNA molecule length to under a thousand basepairs," Meller added. "Because our method avoids amplification, it not only reduces the cost, time and error rate of DNA replication techniques, but also enables the analysis of very long strands of DNA, much longer than current limitations."

With this knowledge in hand, Meller and his team set out to optimize the effect. They used salt gradients to alter the electrical field around the pores, which increased the rate at which DNA molecules were captured and shortened the lag time between molecules, thus reducing the quantity of DNA needed for accurate measurements. Rather than floating around until they happened upon a nanopore, DNA strands were funneled into the openings.

By boosting capture rates by a few orders of magnitude, and reducing the volume of the sample chamber the researchers reduced the number of DNA molecules required by a factor of 10,000 – from about 1 billion sample molecules to 100,000.

###

The research was funded by the National Human Genome Research Institute of the Institutes of Health and by the National Science Foundation. The article, "Electrostatic Focusing of Unlabelled DNA into Nanoscale Pores Using a Salt Gradient," will be available at the Nature web site beginning Dec. 20 at 1 p.m. at http://dx.doi.org/10.1038/natureNNANO.2009.379.

Butterfly proboscis to sip cells

2009-11-25T22:40:00.000-08:00

Nature does every thing the very best way. We shall get solutions to complex problems by keenly observing nature. This is substantiated by the following newsstory

K.S.Parthaarathy

Public release date: 22-Nov-2009

Contact: Jason Bardi
jbardi@aip.org
301-209-3091
American Institute of Physics
Butterfly proboscis to sip cells
Nature-inspired probes be presented at Fluid Dynamics Conference next week

WASHINGTON, D.C. November 18, 2009 -- A butterfly's proboscis looks like a straw -- long, slender, and used for sipping -- but it works more like a paper towel, according to Konstantin Kornev of Clemson University. He hopes to borrow the tricks of this piece of insect anatomy to make small probes that can sample the fluid inside of cells.

Kornev will present his work next week at the 62nd Annual Meeting of the American Physical Society's (APS) Division of Fluid Dynamics will take place from November 22-24 at the Minneapolis Convention Center.

At the scales at which a butterfly or moth lives, liquid is so thick that it is able to form fibers. The insects' liquid food -- drops of water, animal tears, and the juice inside decomposed fruit -- spans nearly three orders of magnitude in viscosity. Pumping liquid through its feeding tube would require an enormous amount of pressure.

"No pump would support that kind of pressure," says Kornev. "The liquid would boil spontaneously."

Instead of pumping, Kornev's findings suggest that butterflies draw liquid upwards using capillary action -- the same force that pulls liquid across a paper towel. The proboscis resembles a rolled-up paper towel, with tiny grooves that pull the liquid upwards along the edges, carrying along the bead of liquid in the middle of the tube. This process is not nearly as affected by viscosity as pumping.

Kornev has been recently awarded an NSF grant to develop artificial probes made of nanofibers that use a similar principal to draw out the viscous liquid inside of cells and examine their contents.

The presentation, "Butterfly proboscis as a biomicrofluidic system" by Konstantin Kornev et al of Clemson University is at 12:01 p.m. on Sunday, November 22, 2009.

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Abstract: http://meetings.aps.org/Meeting/DFD09/Event/110814

MORE MEETING INFORMATION
The 62nd Annual DFD Meeting will be held at the Minneapolis Convention Center in downtown Minneapolis. All meeting information, including directions to the Convention Center is at: http://www.dfd2009.umn.edu/

PRESS REGISTRATION
Credentialed full-time journalist and professional freelance journalists working on assignment for major publications or media outlets are invited to attend the conference free of charge. If you are a reporter and would like to attend, please contact Jason Bardi (jbardi@aip.org, 301-209-3091).

USEFUL LINKS
Main meeting Web site: http://meetings.aps.org/Meeting/DFD09/Content/1629
Searchable form: http://meetings.aps.org/Meeting/DFD09/SearchAbstract
Local Conference Meeting Website: http://www.dfd2009.umn.edu/
PDF of Meeting Abstracts: http://flux.aps.org/meetings/YR09/DFD09/all_DFD09.pdf
Division of Fluid Dynamics page: http://www.aps.org/units/dfd/
Virtual Press Room: SEE BELOW

VIRTUAL PRESS ROOM
The APS Division of Fluid Dynamics Virtual Press Room will contain tips on dozens of stories as well as stunning graphics and lay-language papers detailing some of the most interesting results at the meeting. Lay-language papers are roughly 500 word summaries written for a general audience by the authors of individual presentations with accompanying graphics and multimedia files. The Virtual Press Room will serve as starting points for journalists who are interested in covering the meeting but cannot attend in person. See: http://www.aps.org/units/dfd/pressroom/index.cfm

Currently, the Division of Fluid Dynamics Virtual Press Room contains information related to the 2008 meeting. In mid-November, the Virtual Press Room will be updated for this year's meeting, and another news release will be sent out at that time.

ONSITE WORKSPACE FOR REPORTERS
A reserved workspace with wireless internet connections will be available for use by reporters. It will be located in the meeting exhibition hall (Ballroom AB) at the Minneapolis Convention Center on Sunday and Monday from 8:00 a.m. to 5:00 p.m. and on Tuesday from 8:00 a.m. to noon. Press announcements and other news will be available in the Virtual Press Room.

GALLERY OF FLUID MOTION
Every year, the APS Division of Fluid Dynamics hosts posters and videos that show stunning images and graphics from either computational or experimental studies of flow phenomena. The outstanding entries, selected by a panel of referees for artistic content, originality and ability to convey information, will be honored during the meeting, placed on display at the Annual APS Meeting in March of 2010, and will appear in the annual Gallery of Fluid Motion article in the September 2010 issue of the journal Physics of Fluids.

This year, selected entries from the 27th Annual Gallery of Fluid Motion will be hosted as part of the Fluid Dynamics Virtual Press Room. In mid-November, when the Virtual Press Room is launched, another announcement will be sent out.

ABOUT THE APS DIVISION OF FLUID DYNAMICS
The Division of Fluid Dynamics of the American Physical Society exists for the advancement and diffusion of knowledge of the physics of fluids with special emphasis on the dynamical theories of the liquid, plastic and gaseous states of matter under all conditions of temperature and pressure. See: http://www.aps.org/units/dfd/

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Diagnostic errors in medicine

2009-11-09T16:11:00.000-08:00

Diagnostic errors in medicine

The latest issue of the Archives of internal medicine[2009;169(20):1881-1887] published an interesting paper analyzing the diagnostic errors in medicine. Physicians from a few reputed hospitals in USA discovered that missed or delayed diagnoses are a common but understudied area in patient safety research. They surveyed clinicians to solicit perceived cases of missed and delayed diagnoses to better understand the types, causes, and prevention of such errors.

They administered a 6-item written survey at 20 grand rounds presentations across the United States and by mail at 2 collaborating institutions. They asked the respondents to report three cases of diagnostic errors and to describe their perceived causes, seriousness, and frequency.

Three hundred and ten physicians reported 669 cases from 22 institutions. They excluded cases without diagnostic errors or lacking sufficient details; Of the 583 cases that remained ,162 errors (28%) were rated as major, 241 (41%) as moderate, and 180 (31%) as minor or insignificant. Pulmonary embolism was the most common missed or delayed diagnoses(26 cases [4.5% of total]followed by drug reactions or overdose (26 cases [4.5%]), lung cancer (23 cases [3.9%]), colorectal cancer (19 cases [3.3%]), acute coronary syndrome (18 cases [3.1%]), breast cancer (18 cases [3.1%]), and stroke (15 cases [2.6%]).

Clinicians made errors most frequently in the testing phase (failure to order, report, and follow-up laboratory results) (44%), followed by clinician assessment errors (failure to consider and over-weighing competing diagnosis) (32%), history taking (10%), physical examination (10%), and referral or consultation errors and delays (3%).

The researchers concluded that physicians readily recalled multiple cases of diagnostic errors and were willing to share their experiences. Using a new taxonomy tool and aggregating cases by diagnosis and error type revealed patterns of diagnostic failures that suggested areas for improvement. Systematic solicitation and analysis of such errors can identify potential preventive strategies.

The authors were from Departments of Medicine (Drs Schiff and Kim and Mss Krosnjar and Wisniewski) and Emergency Medicine (Dr Cosby), Cook County Hospital, Chicago, Illinois; Division of General Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts (Drs Schiff and Hasan); Department of Medicine, Rush University, Chicago (Drs Schiff, Abrams, Hasler, and McNutt and Mr Odwazny); Departments of Health Policy and Administration (Dr Kim) and Medical Education (Dr Elstein) and College of Pharmacy (Dr Lambert), University of Illinois at Chicago; and Department of Family and Preventive Medicine, University of California, San Diego (Dr Kabongo).

Spallation Neutron Source first of its kind to reach megawatt power

2009-10-01T18:14:00.001-07:00

Public release date: 29-Sep-2009
Great news
DR Parthasarathy

Contact: Bill Cabage
cabagewh@ornl.gov
865-574-4399
DOE/Oak Ridge National Laboratory
Spallation Neutron Source first of its kind to reach megawatt power

OAK RIDGE, Tenn., Sept. 28, 2009 -- The Department of Energy's Spallation Neutron Source (SNS), already the world's most powerful facility for pulsed neutron scattering science, is now the first pulsed spallation neutron source to break the one-megawatt barrier.

"Advances in the materials sciences are fundamental to the development of clean and sustainable energy technologies. In reaching this milestone of operating power, the Spallation Neutron Source is providing scientists with an unmatched resource for unlocking the secrets of materials at the molecular level," said Dr. William F. Brinkman, Director of DOE's Office of Science.

SNS operators at DOE's Oak Ridge National Laboratory pushed the controls past the megawatt mark on September 18 as the SNS ramped up for its latest operational run.

"The attainment of one megawatt in beam power symbolizes the advancement in analytical resources that are now available to the neutron scattering community through the SNS," said ORNL Director Thom Mason, who led the SNS project during its construction. "This is a great achievement not only for DOE and Oak Ridge National Laboratory, but for the entire community of science."

Before the SNS, the world's spallation neutron sources operated in the hundred-kilowatt range. The SNS actually became a world-record holder in August 2007 when it reached 160 kilowatts, earning it an entry in the Guinness Book of World Records as the world's most powerful pulsed spallation neutron source.

Beam power isn't merely a numbers game. A more powerful beam means more neutrons are spalled from SNS's mercury target. For the researcher, the difference in beam intensity is comparable to the ability to see with a car's headlights versus a flashlight. More neutrons also enhance scientific opportunities, including flexibility for smaller samples and for real-time studies at shorter time scales. For example, experiments will be possible that use just one pulse of neutrons to illuminate the dynamics of scientific processes.

Eventually, the SNS will reach its design power of 1.4 megawatts. The gradual increase of beam power has been an ongoing process since the SNS was completed and activated in late April 2006.

In the meantime, scientists have been performing cutting-edge experiments and materials analysis as its eventual suite of 25 instruments comes on line. As DOE Office of Science user facilities, the SNS and its companion facility, the High Flux Isotope Reactor, host researchers from around the world for neutron scattering experiments.

###

ORNL is managed by UT-Battelle for the Department of Energy.

NOTE TO EDITORS: You may read other press releases from Oak Ridge National Laboratory or learn more about the lab at http://www.ornl.gov

Tel Aviv Univrsity's 'Dust Alert' exposes dangerous invisible pollution, pollen and construction waste

2009-09-23T23:19:00.000-07:00

Public release date: 22-Sep-2009
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Contact: George Hunka
ghunka@aftau.org
212-742-9070
American Friends of Tel Aviv University
Tel Aviv University invention busts dust
TAU's 'Dust Alert' exposes dangerous invisible pollution, pollen and construction waste

Worried that dust from a nearby construction zone will harm your family's health? A new Tel Aviv University tool could either confirm your suspicions or better yet, set your mind at rest.

Prof. Eyal Ben-Dor and his Ph.D student Dr. Sandra Chudnovsky, of TAU's Department of Geography have developed a sensor called "Dust Alert" ― the first of its kind ― to help families and authorities monitor the quality of the air they breathe. Like an ozone gas or carbon monoxide meter, it measures the concentration of small particles that may contaminate the air in your home. Scientific studies on "Dust Alert" appeared recently in the journal Science of the Total Environment, Urban Air Pollution: Problems, Control Technologies and Management Practices.

"It works just like an ozone meter would," says Prof. Ben-Dor. "You put it in your home or office for three weeks, and it can give you real-time contamination levels in terms of dust, pollen and toxins." Functioning like a tiny chemistry lab, the device can precisely determine the chemical composition of the toxins, so homeowners, office managers and factories can act to improve air quality.

Using the measurements, Prof. Ben-Dor can sometimes find a quick remedy for a dusty or pollen-filled home. The solution could be as easy as keeping a window open, he says. "We've found through our ongoing research that some simple actions at home can have a profound effect on the quality of air we breathe."

Instant results

Based on a portable chemical analyzer called a spectrophotometer, the invention can be installed and begin to collect data within minutes, although several weeks' worth of samples produces the best assessment of air quality. The longer period allows for fluctuations in both internal and external environments, such as changing weather patterns.

The "Dust Alert" fills an important need. Polluted air, breathed in for weeks, months and sometimes years, can have fatal consequences, leading to asthma, bronchitis and lung cancer. With findings from Prof. Ben-Dor's invention, urban planners can provide better solutions and mitigate risks. "We can certainly give an accurate forecast about the health of a home or apartment for prospective home owners. If somebody in your family has an allergy, poor air quality can be a deal breaker ," says Prof. Ben-Dor.

Prof. Ben-Dor's device may be most useful in the aftermath of disasters, such as chemical fires, heavy dust storms, hurricanes or tragedies like 9/11. Survivors of these situations are usually unaware of the lingering environmental problems, and the government can't do enough to protect them because no accurate tools exist to define the risk. Using a Dust Alert, residents could be advised to vacate their homes and offices until the dust has cleared, or to take simple precautions such as aerating hazardous rooms in a flat, suggests Prof. Ben-Dor.

Putting dust on the map

According to Prof. Ben-Dor, the Dust Alert could also be used by cities and counties to develop "dust maps" that provide detailed environmental information about streets and neighborhoods, permitting government authorities like the EPA to more successfully identify and prosecute offenders. Currently, for example, there is no system for demonstrating how construction sites compromise people's health.

"Until now, people have had to grin and bear the polluted air they breathe," says Prof. Ben-Dor. "The Dust Alert could provide crucial reliable evidence of pollution, so that society at large can breathe easier. We can see the dust on the furniture and on the windows, but most of us can't see the dust we breathe. For the first time, we are able to detect it and measure its more dangerous components."

With their dust maps, TAU scientists have already correlated urban heat islands with high levels of particulate matter, giving urban planners crucial information for the development of green spaces and city parks. Prof. Ben-Dor also plans to develop his prototype into a home-and-office unit, while offering customized services that can help people decode what's left in the dust.

###

American Friends of Tel Aviv University (www.aftau.org) supports Israel's leading and most comprehensive center of higher learning. In independent rankings, TAU's innovations and discoveries are cited more often by the global scientific community than all but 20 other universities worldwide

Internationally recognized for the scope and groundbreaking nature of its research programs, Tel Aviv University consistently produces work with profound implications for the future.

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Diamonds may be the ultimate MRI probe, say Quantum physicists

2009-09-23T23:08:00.000-07:00

A search for quantum computers led to a medical aplication. One day we may get MRI-like devices that can probe individual drug molecules and living cells.

K.S.Parthasarathy

Public release date: 22-Sep-2009
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Contact: Chad Boutin
boutin@nist.gov
301-975-4261
National Institute of Standards and Technology (NIST)
Diamonds may be the ultimate MRI probe, say Quantum physicists

Diamonds, it has long been said, are a girl's best friend. But a research team including a physicist from the National Institute of Standards and Technology (NIST) has recently found* that the gems might turn out to be a patient's best friend as well.

The team's work has the long-term goal of developing quantum computers, but it has borne fruit that may have more immediate application in medical science. Their finding that a candidate "quantum bit" has great sensitivity to magnetic fields hints that MRI-like devices that can probe individual drug molecules and living cells may be possible.

The candidate system, formed from a nitrogen atom lodged within a diamond crystal, is promising not only because it can sense atomic-scale variations in magnetism, but also because it functions at room temperature. Most other such devices used either in quantum computation or for magnetic sensing must be cooled to nearly absolute zero to operate, making it difficult to place them near live tissue. However, using the nitrogen as a sensor or switch could sidestep that limitation.

Diamond, which is formed of pure carbon, occasionally has minute imperfections within its crystalline lattice. A common impurity is a "nitrogen vacancy", in which two carbon atoms are replaced by a single atom of nitrogen, leaving the other carbon atom's space vacant. Nitrogen vacancies are in part responsible for diamond's famed luster, for they are actually fluorescent: when green light strikes them, the nitrogen atom's two excitable unpaired electrons glow a brilliant red.

The team can use slight variations in this fluorescence to determine the magnetic spin of a single electron in the nitrogen. Spin is a quantum property that has a value of either "up" or "down," and therefore could represent one or zero in binary computation. The team's recent achievement was to transfer this quantum information repeatedly between the nitrogen electron and the nuclei of adjacent carbon atoms, forming a small circuit capable of logic operations. Reading a quantum bit's spin information—a fundamental task for a quantum computer—has been a daunting challenge, but the team demonstrated that by transferring the information back and forth between the electron and the nuclei, the information could be amplified, making it much easier to read.

Still, NIST theoretical physicist Jacob Taylor said the findings are "evolutionary, not revolutionary" for the quantum computing field and that the medical world may reap practical benefits from the discovery long before a working quantum computer is built. He envisions diamond-tipped sensors performing magnetic resonance tests on individual cells within the body, or on single molecules drug companies want to investigate—a sort of MRI scanner for the microscopic. "That's commonly thought not to be possible because in both of these cases the magnetic fields are so small," Taylor says. "But this technique has very low toxicity and can be done at room temperature. It could potentially look inside a single cell and allow us to visualize what's happening in different spots."

The Harvard University-based team also includes scientists from the Joint Quantum Institute (a partnership of NIST and the University of Maryland), the Massachusetts Institute of Technology and Texas A&M University.

###

* L. Jiang, J.S. Hodges, J.R. Maze, P. Maurer, J.M. Taylor, D.G. Cory, P.R. Hemmer, R.L. Walsworth, A. Yacoby, A.S. Zibrov and M.D. Lukin. Repetitive readout of a single electronic spin via quantum logic with nuclear spin ancillae. Science, DOI: 10.1126/science.1176496, published online Sept. 10, 2009.

See http://www.nist.gov/public_affairs/techbeat/tb2009_0922.htm#diamonds for illustration to accompany story.

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Study identifies which children do not need CT scans after head trauma

2009-09-15T05:12:00.000-07:00

There is general awareness that children must not be exposed to unwanted x-ray doses. This paper came ta the opportune time. Bold implementation of the guidelines will be essential. Professional associations must review the work urgently and accept the guidelines with modifications if any required

Dr.K.S.Parthasarathy

EureKAlert

Public release date: 14-Sep-2009
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Contact: Charlie Casey
charles.casey@ucdmc.ucdavis.edu
916-734-9048
University of California - Davis - Health System
Study identifies which children do not need CT scans after head trauma
Research provides new guidelines to identify children with mild injuries and reduce radiation exposure from CT

A substantial percentage of children who get CT scans after apparently minor head trauma do not need them, and as a result are put at increased risk of cancer due to radiation exposure. After analyzing more than 42,000 children with head trauma, a national research team led by two UC Davis emergency department physicians has developed guidelines for doctors who care for children with head trauma aimed at reducing those risks.

Their findings appear in an article published online today and in an upcoming edition of The Lancet.

The collaborative study includes data collected at 25 hospitals from children who were evaluated for the possibility of serious brain injury following trauma to the head. Researchers found that one in five children over the age of 2 and nearly one-quarter of those under 2 who received CT scans following head trauma did not need them because they were at very low risk of having serious brain injuries. In these low-risk children, the risk of developing cancer due to radiation exposure outweighed the risk of serious brain injury.

"When you have a sample size this large, it is easier to get your hands on the truth," said Nathan Kuppermann, professor and chair of emergency medicine, professor of pediatrics at UC Davis Children's Hospital and lead author of the study. "We think our investigation provides the best available evidence regarding the use of CT scans in children with head trauma, and it indicates that CT use can be safely reduced by eliminating its application in those children who are at very low risk of serious brain injuries."

As part of the study, Kuppermann and his colleagues developed a set of rules for identifying low-risk patients who would not need a CT. The "prediction rules" for children under 2 and for those 2 and older depend on the presence or absence of various symptoms and circumstances, including the way the injury was sustained, a history of loss of consciousness, neurological status at the time of evaluation and clinical evidence of skull fracture for both age groups. The use of CT in patients who do not fall into the low-risk group identified by the prediction rules will depend on other factors, such as the physician's experience, the severity and number of symptoms, and other factors.

The Centers for Disease Control estimates that 435,000 children under 14 visit emergency rooms every year to be evaluated for traumatic brain injury (TBI). Not all head trauma results in a TBI. The severity of a brain injury may range from mild, causing brief change in mental status or consciousness, to severe, causing permanent symptoms and irreversible damage.

For years, studies have suggested that CT scans were being overused to rule out traumatic brain injuries. However, those studies were considered too small to be sufficiently accurate and not precise enough to be widely applicable to a general population. The sheer size of the current study, and the fact that the investigators created the accurate prediction rules with one large group of children with head trauma and then tested the rules on another large but separate group to demonstrate their validity, allows physicians to have confidence in the results. The researchers emphasized, however, that the rules are not intended to replace clinical judgment.

"We're arming the clinician with the best available evidence so that they can make the best decisions," said James Holmes, professor of emergency medicine at UC Davis School of Medicine and a co-author of the report. "There certainly are instances when the risks of radiation are worth it, such as in cases of blunt head trauma which result in changes in neurological status or clinical evidence of skull fractures. However, clinicians need reliable data to help them make those judgment calls when it is not clear whether or not a patient needs a CT. Until now, physicians haven't had data based on large and validated research."

The current study comes on the heels of an article published in late August by The New England Journal of Medicine that showed that at least 4 million Americans under age 65 are exposed to high doses of radiation each year from medical imaging tests, with CT scans accounting for almost one half of the total radiation dose. About 10 percent of those get more than the maximum annual exposure allowed for nuclear power plant employees or anyone else who works with radioactive material.

Studies show that exposure to radiation increases the risk of cancer. Radiation exposure to the brain of developing children is of particular concern and must be weighed carefully against the risk of traumatic brain injury that could cause permanent damage or death if not identified early. If the new guidelines are applied appropriately, the use of CT scans nationwide could be significantly reduced.

The effort was made possible by the Pediatric Emergency Care Applied Research Network (PECARN), which enabled the massive collection of data. Supported by the U.S. Department of Health and Human Services' Emergency Medical Services for Children Program, PECARN is the first federally-funded, multi-institutional network for research in pediatric emergency medicine in the nation. The network conducts research into the prevention and management of acute illnesses and injuries in children and youth across the continuum of emergency medicine and health care.

"Children with medical and traumatic illnesses usually have good outcomes, but you need a lot of children to assess factors and treatments that predict both good and bad outcomes. By studying large numbers of children, in a variety of settings and from diverse populations, the results will more likely be applicable to the general population. That's the power of PECARN," Kuppermann said. "Combined, our network of emergency departments around the country evaluates approximately 1 million children per year."

Along with the UC Davis team, key PECARN researchers in the Lancet study included Peter S. Dayan, from New York-Presbyterian Hospital and Columbia University Medical Center in New York; John D. Hoyle, Jr., from Helen DeVos Children's Hospital in Grand Rapids; Shireen M. Atabaki, from Children's National Medical Center in Washington, D.C.; and Richard Holubkov from the PECARN Data Coordinating Center at the University of Utah.

In order to create the prediction rules, the PECARN investigators studied outcomes in more than 42,000 children with minor initial symptoms and signs of head trauma. CT scans were performed in nearly 15,000 of those patients. Serious brain injuries were diagnosed in 376 children, and 60 children underwent neurosurgery.

Using these data, the researchers developed two prediction rules for identifying mild cases that do not need CT scans. One rule was developed for children under the age of 2 and another for those 2 and over. It was important to study children under 2 separately because they cannot communicate their symptoms or offer information as well as older children, and they are more sensitive to the effects of radiation.

Children under 2 who fell into the low-risk group showed normal mental status, no scalp swelling, no significant loss of consciousness, no palpable skull fracture, were normal-acting (according to the parent), and had an injury that was sustained in a non-severe way. Severe accidents, which excluded children from the low-risk group, included motor vehicle crashes in which the patient was ejected, and bicycle accidents involving automobiles, in which the patient was not wearing a helmet. Key indicators for children older than 2 who were at low-risk for brain injury included normal mental status, no loss of consciousness, no vomiting, no signs of fracture of the base of skull, no severe headache, and they did not sustain the injury in a serious accident.

The researchers then validated these rules by applying them to data from a second population of more than 8,600 children. In more than 99.9 percent of the cases, the rules accurately predicted children who were not diagnosed with serious brain injuries and were therefore indeed at low risk..

The researchers also identified and separated children at intermediate and high risk of serious brain injuries. Those in the high-risk group should receive CT scans, the researchers wrote. The PECARN team is currently working on refining recommendations for the use of CT scans in those at intermediate risk. Until now, emergency room physicians have relied mostly on instincts when deciding whether or not the symptoms of a child with head trauma warrant the use of CT.

"Now we have much better evidence to assist with making decisions regarding CT use," Kuppermann said.

###

UC Davis has been part of PECARN since its inception in 2001. It is the leading center in one of four PECARN Research Nodes, which also includes Children's Hospital of Philadelphia; St. Louis Children's Hospital; Children's Hospital of Wisconsin; Cincinnati Children's Hospital Medical Center; and Primary Children's Medical Center in Salt Lake City.

A total of 32 PECARN researchers were substantially involved in this study. This research was supported by the Emergency Medical Services for Children program of the Maternal and Child Health Bureau, and the Maternal and Child Health Bureau Research Program, Health Resources and Services Administration, U.S. Department of Health and Human Services.

Caltech scientists develop novel use of neurotechnology to solve classic social problem

2009-09-11T00:51:00.000-07:00

Public release date: 10-Sep-2009

Contact: Lori Oliwenstein
lorio@caltech.edu
626-395-3631
California Institute of Technology
Caltech scientists develop novel use of neurotechnology to solve classic social problem
Research shows how brain imaging can be used to create new and improved solutions to the public-goods provision problem

PASADENA, Calif.—Economists and neuroscientists from the California Institute of Technology (Caltech) have shown that they can use information obtained through functional magnetic resonance imaging (fMRI) measurements of whole-brain activity to create feasible, efficient, and fair solutions to one of the stickiest dilemmas in economics, the public goods free-rider problem—long thought to be unsolvable.

This is one of the first-ever applications of neurotechnology to real-life economic problems, the researchers note. "We have shown that by applying tools from neuroscience to the public-goods problem, we can get solutions that are significantly better than those that can be obtained without brain data," says Antonio Rangel, associate professor of economics at Caltech and the paper's principal investigator.

The paper describing their work was published today in the online edition of the journal Science, called Science Express.

Examples of public goods range from healthcare, education, and national defense to the weight room or heated pool that your condominium board decides to purchase. But how does the government or your condo board decide which public goods to spend its limited resources on? And how do these powers decide the best way to share the costs?

"In order to make the decision optimally and fairly," says Rangel, "a group needs to know how much everybody is willing to pay for the public good. This information is needed to know if the public good should be purchased and, in an ideal arrangement, how to split the costs in a fair way."

In such an ideal arrangement, someone who swims every day should be willing to pay more for a pool than someone who hardly ever swims. Likewise, someone who has kids in public school should have more of her taxes put toward education.

But providing public goods optimally and fairly is difficult, Rangel notes, because the group leadership doesn't have the necessary information. And when people are asked how much they value a particular public good—with that value measured in terms of how many of their own tax dollars, for instance, they'd be willing to put into it—their tendency is to lowball.

Why? "People can enjoy the good even if they don't pay for it," explains Rangel. "Underreporting its value to you will have a small effect on the final decision by the group on whether to buy the good, but it can have a large effect on how much you pay for it."

In other words, he says, "There's an incentive for you to lie about how much the good is worth to you."

That incentive to lie is at the heart of the free-rider problem, a fundamental quandary in economics, political science, law, and sociology. It's a problem that professionals in these fields have long assumed has no solution that is both efficient and fair.

In fact, for decades it's been assumed that there is no way to give people an incentive to be honest about the value they place on public goods while maintaining the fairness of the arrangement.

"But this result assumed that the group's leadership does not have direct information about people's valuations," says Rangel. "That's something that neurotechnology has now made feasible."

And so Rangel, along with Caltech graduate student Ian Krajbich and their colleagues, set out to apply neurotechnology to the public-goods problem.

In their series of experiments, the scientists tried to determine whether functional magnetic resonance imaging (fMRI) could allow them to construct informative measures of the value a person assigns to one or another public good. Once they'd determined that fMRI images—analyzed using pattern-classification techniques—can confer at least some information (albeit "noisy" and imprecise) about what a person values, they went on to test whether that information could help them solve the free-rider problem.

They did this by setting up a classic economic experiment, in which subjects would be rewarded (paid) based on the values they were assigned for an abstract public good.

As part of this experiment, volunteers were divided up into groups. "The entire group had to decide whether or not to spend their money purchasing a good from us," Rangel explains. "The good would cost a fixed amount of money to the group, but everybody would have a different benefit from it."

The subjects were asked to reveal how much they valued the good. The twist? Their brains were being imaged via fMRI as they made their decision. If there was a match between their decision and the value detected by the fMRI, they paid a lower tax than if there was a mismatch. It was, therefore, in all subjects' best interest to reveal how they truly valued a good; by doing so, they would on average pay a lower tax than if they lied.

"The rules of the experiment are such that if you tell the truth," notes Krajbich, who is the first author on the Science paper, "your expected tax will never exceed your benefit from the good."

In fact, the more cooperative subjects are when undergoing this entirely voluntary scanning procedure, "the more accurate the signal is," Krajbich says. "And that means the less likely they are to pay an inappropriate tax."

This changes the whole free-rider scenario, notes Rangel. "Now, given what we can do with the fMRI," he says, "everybody's best strategy in assigning value to a public good is to tell the truth, regardless of what you think everyone else in the group is doing."

And tell the truth they did—98 percent of the time, once the rules of the game had been established and participants realized what would happen if they lied. In this experiment, there is no free ride, and thus no free-rider problem.

"If I know something about your values, I can give you an incentive to be truthful by penalizing you when I think you are lying," says Rangel.

While the readings do give the researchers insight into the value subjects might assign to a particular public good, thus allowing them to know when those subjects are being dishonest about the amount they'd be willing to pay toward that good, Krajbich emphasizes that this is not actually a lie-detector test.

"It's not about detecting lies," he says. "It's about detecting values—and then comparing them to what the subjects say their values are."

"It's a socially desirable arrangement," adds Rangel. "No one is hurt by it, and we give people an incentive to cooperate with it and reveal the truth."

"There is mind reading going on here that can be put to good use," he says. "In the end, you get a good produced that has a high value for you."

From a scientific point of view, says Rangel, these experiments break new ground. "This is a powerful proof of concept of this technology; it shows that this is feasible and that it could have significant social gains."

And this is only the beginning. "The application of neural technologies to these sorts of problems can generate a quantum leap improvement in the solutions we can bring to them," he says.

Indeed, Rangel says, it is possible to imagine a future in which, instead of a vote on a proposition to fund a new highway, this technology is used to scan a random sample of the people who would benefit from the highway to see whether it's really worth the investment. "It would be an interesting alternative way to decide where to spend the government's money," he notes.

###

In addition to Rangel and Krajbich, other authors on the Science paper, "Using neural measures of economic value to solve the public goods free-rider problem," include Caltech's Colin Camerer, the Robert Kirby Professor of Behavioral Economics, and John Ledyard, the Allen and Lenabelle Davis Professor of Economics and Social Sciences. Their work was funded by grants from the National Science Foundation, the Gordon and Betty Moore Foundation, and the Human Frontier Science Program.

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Environmental scientists estimate that China could meet its entire future energy needs by wind alone

2009-09-11T00:46:00.000-07:00

Public release date: 10-Sep-2009

Contact: Michael Patrick Rutter
mrutter@seas.harvard.edu
617-496-3815
Harvard University
Environmental scientists estimate that China could meet its entire future energy needs by wind alone
Study suggests that wind is ecologically and economically practical and could reduce CO2 emissions

Cambridge, Mass. – September 10, 2009 – A team of environmental scientists from Harvard and Tsinghua University demonstrated the enormous potential for wind-generated electricity in China. Using extensive metrological data and incorporating the Chinese government's energy bidding and financial restrictions for delivering wind power, the researchers estimate that wind alone has the potential to meet the country's electricity demands projected for 2030.

The switch from coal and other fossil fuels to greener wind-based energy could also mitigate CO2 emissions, thereby reducing pollution. The report appeared as a cover story in the September 11th issue of Science.

"The world is struggling with the question of how do you make the switch from carbon-rich fuels to something carbon-free," said lead author Michael B. McElroy, Gilbert Butler Professor of Environmental Studies at Harvard's School of Engineering and Applied Sciences (SEAS).

China has become second only to the U.S. in its national power generating capacity— 792.5 gigawatts per year with an expected future 10 percent annual increase—and is now the world's largest CO2 emitter. Thus, added McElroy, "the real question for the globe is: What alternatives does China have?"

While wind-generated energy accounts for only 0.4 percent of China's total current electricity supply, the country is rapidly becoming the world's fastest growing market for wind power, trailing only the U.S., Germany, and Spain in terms of installed capacities of existing wind farms.

Development of renewable energy in China, especially wind, received an important boost with passage of the Renewable Energy Law in 2005; the law provides favorable tax status for alternative energy investments. The Chinese government also established a concession bidding process to guarantee a reasonable return for large wind projects.

"To determine the viability of wind-based energy for China we established a location-based economic model, incorporating the bidding process, and calculated the energy cost based on geography," said co-author Xi Lu, a graduate student in McElroy's group at SEAS. "Using the same model we also evaluated the total potentials for wind energy that could be realized at a certain cost level."

Specifically, the researchers used meteorological data from the Goddard Earth Observing Data Assimilation System (GEOS) at NASA. Further, they assumed the wind energy would be produced from a set of land-based 1.5-megawatt turbines operating over non-forested, ice-free, rural areas with a slope no more than 20 percent.

"By bringing the capabilities of atmospheric science to the study of energy we were able to view the wind resource in a total context," explained co-author Chris P. Nielsen, Executive Director of the Harvard China Project, based at SEAS.

The analysis indicated that a network of wind turbines operating at as little as 20 percent of their rated capacity could provide potentially as much as 24.7 petawatt-hours of electricity annually, or more than seven times China's current consumption. The researchers also determined that wind energy alone, at around 7.6 U.S. Cents per kilowatt-hour, could accommodate the country's entire demand for electricity projected for 2030.

"Wind farms would only need to take up land areas of 0.5 million square kilometers, or regions about three quarters of the size of Texas. The physical footprints of wind turbines would be even smaller, allowing the areas to remain agricultural," said Lu.

By contrast, to meet the increased demand for electricity during the next 20 years using fossil fuel-based energy sources, China would have to construct coal-fired power plants that could produce the equivalent of 800 gigawatts of electricity, resulting in a potential increase of 3.5 gigatons of CO2 per year. The use of cleaner wind energy could both meet future demands and, even if only used to supplement existing energy sources, significantly reduce carbon emissions.

Moving to a low-carbon energy future would require China to make an investment of around $900 billion dollars (at current prices) over the same twenty-year period. The scientists consider this a large but not unreasonable investment given the present size of the Chinese economy. Moreover, whatever the energy source, the country will need to build and support an expanded energy grid to accommodate the anticipated growth in power demand.

"We are trying to cut into the current defined demand for new electricity generation in China, which is roughly a gigawatt a week—or an enormous 50 gigawatts per year," said McElroy. "China is bringing on several coal fire power plants a week. By publicizing the opportunity for a different way to go we will hope to have a positive influence."

In the coming months, the researchers plan to conduct a more intensive wind study in China, taking advantage of 25-year data with significantly higher spatial resolution for north Asian regions to investigate the geographical year-to-year variations of wind. The model used for assessing China could also be applied for assessing wind potential anywhere in the world, onshore and offshore, and could be extended to solar generated electricity.

###

Yuxuan Wang, Associate Professor in the Department of Environmental Science and Engineering at Tsinghua University, Beijing, China, also contributed to the study. The team's research was supported by a grant from the National Science Foundation (NSF).

Carbon nanotubes could make efficient solar cells

2009-09-11T00:44:00.000-07:00

Public release date: 10-Sep-2009

Contact: Blaine Friedlander
bpf2@cornell.edu
607-254-8093
Cornell University
Carbon nanotubes could make efficient solar cells

Using a carbon nanotube instead of traditional silicon, Cornell researchers have created the basic elements of a solar cell that hopefully will lead to much more efficient ways of converting light to electricity than now used in calculators and on rooftops.

The researchers fabricated, tested and measured a simple solar cell called a photodiode, formed from an individual carbon nanotube. Reported online Sept. 11 in the journal Science, the researchers -- led by Paul McEuen, the Goldwin Smith Professor of Physics, and Jiwoong Park, assistant professor of chemistry and chemical biology -- describe how their device converts light to electricity in an extremely efficient process that multiplies the amount of electrical current that flows. This process could prove important for next-generation high efficiency solar cells, the researchers say.

"We are not only looking at a new material, but we actually put it into an application -- a true solar cell device," said first author Nathan Gabor, a graduate student in McEuen's lab.

The researchers used a single-walled carbon nanotube, which is essentially a rolled-up sheet of graphene, to create their solar cell. About the size of a DNA molecule, the nanotube was wired between two electrical contacts and close to two electrical gates, one negatively and one positively charged. Their work was inspired in part by previous research in which scientists created a diode, which is a simple transistor that allows current to flow in only one direction, using a single-walled nanotube. The Cornell team wanted to see what would happen if they built something similar, but this time shined light on it.

Shining lasers of different colors onto different areas of the nanotube, they found that higher levels of photon energy had a multiplying effect on how much electrical current was produced.

Further study revealed that the narrow, cylindrical structure of the carbon nanotube caused the electrons to be neatly squeezed through one by one. The electrons moving through the nanotube became excited and created new electrons that continued to flow. The nanotube, they discovered, may be a nearly ideal photovoltaic cell because it allowed electrons to create more electrons by utilizing the spare energy from the light.

This is unlike today's solar cells, in which extra energy is lost in the form of heat, and the cells require constant external cooling.

Though they have made a device, scaling it up to be inexpensive and reliable would be a serious challenge for engineers, Gabor said.

"What we've observed is that the physics is there," he said.

###

The research was supported by Cornell's Center for Nanoscale Systems and the Cornell NanoScale Science and Technology Facility, both National Science Foundation facilities, as well as the Microelectronics Advanced Research Corporation Focused Research Center on Materials, Structures and Devices. Research collaborators also included Zhaohui Zhong, of the University of Michigan, and Ken Bosnick, of the National Institute for Nanotechnology at University of Alberta.

(Text by Anne Ju, Cornell Chronicle)

Making more efficient fuel cells

2009-09-07T00:40:00.000-07:00

Public release date: 6-Sep-2009
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Contact: Dianne Stilwell
diannestilwell@me.com
44-795-720-0214
Society for General Microbiology
Making more efficient fuel cells

Bacteria that generate significant amounts of electricity could be used in microbial fuel cells to provide power in remote environments or to convert waste to electricity. Professor Derek Lovley from the University of Massachusetts, USA isolated bacteria with large numbers of tiny projections called pili which were more efficient at transferring electrons to generate power in fuel cells than bacteria with a smooth surface. The team's findings were reported at the Society for General Microbiology's meeting at Heriot-Watt University, Edinburgh, today (7 September).

The researchers isolated a strain of Geobacter sulfurreducens which they called KN400 that grew prolifically on the graphite anodes of fuel cells. The bacteria formed a thick biofilm on the anode surface, which conducted electricity. The researchers found large quantities of pilin, a protein that makes the tiny fibres that conduct electricity through the sticky biofilm.

"The filaments form microscopic projections called pili that act as microbial nanowires," said Professor Lovley, "using this bacterial strain in a fuel cell to generate electricity would greatly increase the cell's power output."

The pili on the bacteria's surface seemed to be primarily for electrical conduction rather than to help them to attach to the anode; mutant forms without pili were still able to stay attached.

Microbial fuel cells can be used in monitoring devices in environments where it is difficult to replace batteries if they fail but to be successful they need to have an efficient and long-lasting source of power. Professor Lovley described how G. sulfurreducens strain KN400 might be used in sensors placed on the ocean floor to monitor migration of turtles.

###

Using waste to recover waste uranium

2009-09-07T00:38:00.000-07:00

Public release date: 6-Sep-2009
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Contact: Dianne Stilwell
diannestilwell@me.com
44-795-720-0214
Society for General Microbiology
Using waste to recover waste uranium

Using bacteria and inositol phosphate, a chemical analogue of a cheap waste material from plants, researchers at Birmingham University have recovered uranium from the polluted waters from uranium mines. The same technology can also be used to clean up nuclear waste. Professor Lynne Macaskie, this week (7-10 September), presented the group's work to the Society for General Microbiology's meeting at Heriot-Watt University, Edinburgh.

Bacteria, in this case, E. coli, break down a source of inositol phosphate (also called phytic acid), a phosphate storage material in seeds, to free the phosphate molecules. The phosphate then binds to the uranium forming a uranium phosphate precipitate on the bacterial cells that can be harvested to recover the uranium.

This process was first described in 1995, but then a more expensive additive was used and that, combined with the then low price of uranium, made the process uneconomic. The discovery that inositol phosphate was potentially six times more effective as well as being a cheap waste material means that the process becomes economically viable, especially as the world price of uranium is likely to increase as countries move to expand their nuclear technologies in a bid to produce low-carbon energy.

As an example, if pure inositol phosphate, bought from a commercial supplier is used, the cost of this process is £1.72 per gram of uranium recovered. If a cheaper source of inositol phosphate is used (eg calcium phytate) the cost reduces to £0.09 for each gram of recovered uranium. At 2007 prices, uranium cost £0.211/g; it is currently £0.09/g. These prices make the process economic overall because there is also an environmental protection benefit. Use of low-grade inositol phosphate from agricultural wastes would bring the cost down still further and the economic benefit will also increase as the price of uranium is forecast to rise again.

"The UK has no natural uranium reserves, although a significant amount of uranium is produced in nuclear wastes. There is no global shortage of uranium but from the point of view of energy security the EU needs to be able to recover as much uranium as possible from mine run-offs (which in any case pollute the environment) as well as recycling as much uranium as possible from nuclear wastes," commented Professor Macaskie, "By using a cheap feedstock easily obtained from plant wastes we have shown that an economic, scalable process for uranium recovery is possible".

###

2009-07-03T02:52:00.000-07:00

Public release date: 2-Jul-2009

Contact: Andreas Willert
andreas.willert@enas.fraunhofer.de
49-371-531-32109
Fraunhofer-Gesellschaft
Printable batteries

This release is available in German.

IMAGE: The small, thin battery comes out of the printer and can be applied to flexible substrates.
Click here for more information.

In the past, it was necessary to race to the bank for every money transfer and every bank statement. Today, bank transactions can be easily carried out at home. Now where is that piece of paper again with the TAN numbers? In the future you can spare yourself the search for the number. Simply touch your EC card and a small integrated display shows the TAN number to be used. Just type in the number and off you go. This is made possible by a printable battery that can be produced cost-effectively on a large scale. It was developed by a research team led by Prof. Dr. Reinhard Baumann of the Fraunhofer Research Institution for Electronic Nano Systems ENAS in Chemnitz together with colleagues from TU Chemnitz and Menippos GmbH. "Our goal is to be able to mass produce the batteries at a price of single digit cent range each," states Dr. Andreas Willert, group manager at ENAS.

The characteristics of the battery differ significantly from those of conventional batteries. The printable version weighs less than one gram on the scales, is not even one millimeter thick and can therefore be integrated into bank cards, for example. The battery contains no mercury and is in this respect environmentally friendly. Its voltage is 1.5 V, which lies within the normal range. By placing several batteries in a row, voltages of 3 V, 4.5 V and 6 V can also be achieved. The new type of battery is composed of different layers: a zinc anode and a manganese cathode, among others. Zinc and manganese react with one another and produce electricity. However, the anode and the cathode layer dissipate gradually during this chemical process. Therefore, the battery is suitable for applications which have a limited life span or a limited power requirement, for instance greeting cards.

The batteries are printed using a silk-screen printing method similar to that used for t-shirts and signs. A kind of rubber lip presses the printing paste through a screen onto the substrate. A template covers the areas that are not to be printed on. Through this process it is possible to apply comparatively large quantities of printing paste, and the individual layers are slightly thicker than a hair. The researchers have already produced the batteries on a laboratory scale. At the end of this year, the first products could possibly be finished.

###

MIT: Slow growth of nuclear could harm climate efforts

2009-05-21T10:19:00.001-07:00

The rate of deployment of new nuclear power plants around the world has been much slower than needed in order to combat climate change, the Massachusetts Institute of Technology (MIT) said in an update of its in-depth study on the future of nuclear power.
K.S.Parthasarathy

WNN
Energy And Environment
MIT: Slow growth of nuclear could harm climate efforts
21 May 2009

The rate of deployment of new nuclear power plants around the world has been much slower than needed in order to combat climate change, the Massachusetts Institute of Technology (MIT) said in an update of its in-depth study on the future of nuclear power.

The 2003 edition of the Future of Nuclear Power report said "that in order to make a serious contribution to alleviating global climate change, the world would need new nuclear plants with a total capacity of at least a terawatt [1000 gigawatts] by 2050."

In its updated study, MIT says, "Since the 2003 report, interest in using electricity for plug-in hybrids and electric cars to replace motor gasoline has increased, thus placing an even greater importance on exploiting the use of carbon-free electricity generating technologies."

It added, "With regard to nuclear power, while there has been some progress since 2003, increased deployment of nuclear power has been slow both in the United States and globally, in relation to the illustrative scenario examined in the 2003 report."

MIT noted, "While the intent to build new plants has been made public in several countries, there are only few firm commitments outside of Asia, in particular China, India, and Korea, to construction projects at this time. Even if all the announced plans for new nuclear power plant construction are realized, the total will be well behind that needed for reaching a thousand gigawatts of new capacity worldwide by 2050."

In its updated study, MIT says that, compared to 2003, "the motivation to make more use of nuclear power is greater, and more rapid progress is needed in enabling the option of nuclear power expansion to play a role in meeting the global warming challenge." It added, "The sober warning is that if more is not done, nuclear power will diminish as a practical and timely option for deployment at a scale that would constitute a material contribution to climate change risk mitigation."

Construction costs up

The latest study noted that, "Since 2003 construction costs for all types of large-scale engineered projects have escalated dramatically. The estimated cost of constructing a nuclear power plant has increased at a rate of 15% per year heading into the current economic downturn. This is based both on the cost of actual builds in Japan and Korea and on the projected cost of new plants planned for in the United States. Capital costs for both coal and natural gas have increased as well, although not by as much. The cost of natural gas and coal that peaked sharply is now receding. Taken together, these escalating costs leave the situation [of relative costs] close to where it was in 2003."

According to MIT's study, the overnight capital cost of constructing a nuclear power plant is $4000 per kilowatt (kW), in 2007 dollars. This compares with a figure of $2000/kW, in 2002 dollars, given in the original 2003 study.

The updated study says that, applying the same cost of capital to nuclear as to coal and gas, nuclear came out at 6.6 c/kWh, coal at 8.3 cents and gas at 7.4 cents, assuming a carbon charge of $25 per tonne of CO2 on the latter.

[The updated study can be downloaded from MIT's website]

2009-05-21T05:19:00.000-07:00

Will this development help countries which have difficulties in getting electric power due to the peculiarities of geography?
K.S.Parthasarathy

WNN
New Nuclear
Assembly of Russian floating plant starts
20 May 2009

A ceremony has been held to mark the start of the assembly of the world's first floating nuclear power plant in St Petersburg, Russia. Construction had earlier been transferred from Severodvinsk.

The keel was originally laid for the first floating plant - the Akademik Lomonosov - at the Sevmash shipyard in Severodvinsk in April 2007. However, in 2008, Rosatom said that it was to transfer its construction to the Baltiysky Zavod shipbuilding company in Saint Petersburg because Sevmash was inundated with military contracts.

Click to enlarge
Five floating reactors could go to Gazprom to power oil and
gas extraction in Kola and Yamal, with four more used in
northern Yakutia in connection with mining operations. Seven
or eight units could be produced by 2015. (Click to enlarge)

A contract was signed on 27 February 2009 between Rosatom and the Baltiysky Zavod shipyard for completion of the plant. The contract was valued at almost 10 billion roubles ($315 million). A new keel has now been laid at Saint Petersburg for the first floating plant. As part of the contract, Baltiysky Zavod will receive the incomplete floating plants started by Sevmash.

The first plant will house two 35 MW KLT-40S nuclear reactors, similar to those used in Russia's nuclear powered ice breakers, and two generators, and will be capable of supplying a city of 200,000 people. OKBM will design and supply the reactors, while Kaluga Turbine Plant will supply the turbo-generators.

The Akademik Lomonosov was originally destined for the Archangelsk industrial shipyard, which is near to Severodvinsk in northwestern Russia, but the vessel is now destined for Vilyuchinsk, in the Kamchatka region in Russia's far east.

Baltiysky Zavod is to complete the floating plant in 2011. It should then be ready for transportation by the second quarter of 2012 and is set to be handed over to Energoatom by the end of 2012. Rosatom is planning to construct seven further floating nuclear power plants in addition to the one now under construction, with several remote areas under consideration for their deployment. Gazprom is expected to use a number of the floating units in order to exploit oil and gas fields near the Kola and Yamal Peninsulars.

Speaking at the ceremony, Sergey Obozov, director general of Energoatom, said that construction of a second floating plant may start in the autumn of 2010. He said, "We already have agreement with the authorities of Chukotka to station the plant in Pevek."

Bacteria with a built-in thermometer

2009-05-21T04:49:00.000-07:00

Enigmatic features of tiny creatures
Parthasarathy

[ Public release date: 20-May-2009

Contact: Dr. Bastian Dornbach
bastian.dornbach@helmhotz-hzi.de
49-053-161-811-407
Helmholtz Association of German Research Centres
Bacteria with a built-in thermometer
Researchers at the Helmholtz Center demonstrate how bacteria measure temperature and thereby control infection

Researchers in the "Molecular Infection Biology group" at the Helmholtz Centre for Infection Research (HZI) in Braunschweig and the Braunschweig Technical University could now demonstrate for the first time that bacteria of the Yersinia genus possess a unique protein thermometer – the protein RovA - which assists them in the infection process. RovA is a multi-functional sensor: it measures both the temperature of its host as well as the host's metabolic activity and nutrients. If these are suitable for the survival of the bacteria, the RovA protein activates genes for the infection process to begin. These results have now been published in the current online edition of the PLoS Pathogens science magazine.

Yersinia can trigger various different diseases: best well-known is the Yersinia pestis type which caused the Plague in medieval times. This led to the death of around a third of Europe's population. The Yersinia enterocolitica and Yersinia pseudotuberculosis species cause an inflammation of the intestines following food poisoning: the bacteria infect the cells of the intestines, leading to heavy bouts of diarrhoea. The Yersinia bacteria contain invasin as a surface protein to help them penetrate the intestinal cells. The immune cells quickly identify this so-called virulence factor as a danger and launch an immune response. To avoid this, the bacteria quickly lose the invasin soon after entering the body. The germs then adapt their metabolism and feed on the nutrients prepared by the host cells. They also produce substances which kill off the body's defence cells, such as phagocytes. Little was known about how Yersinia is able to regulate these individual stages of infection until now.

Researchers at the HZI, led by Petra Dersch, have now identified how these mechanisms work. The RovA protein plays a key role. The protein reads the temperature for the bacteria. Depending on the environment of the bacteria, this protein either contains the factors required for the infection to begin or else adapts to life within the host. "The functioning of RovA in this way is unique among bacteria," says Petra Dersch.

If inhabiting an environment of around 25°C, the protein RovA ensures that the Yersinia bacteria form invasin as a surface protein. This ensures that the Yersinia can penetrate the intestinal cells immediately upon reaching the 37°C intestine via food. In this warm environment, the RovA alters its form and de-activates the gene for invasin production. Without invasin on their surface, the Yersinia bacteria are invisible to the body's immune system. In its new form, the RovA can now activate other genes in the bacteria to adapt the Yersinia metabolism to that of the host.

Until now, little was known about RovA and the fact that it reacts to temperature. Researchers were presented with a puzzle: "We have long been searching for the mechanisms which regulate RovA activity," says Petra Dersch. "It was therefore all the more surprising to discover that RovA controls various processes by acting as a thermometer and as such is self-regulating". At the end of the process, the RovA is responsible for its own decomposition. If the initial stages of infection prove successful, the Yersinia bacteria no longer need the RovA: in its modified form at 37°C, enzymes in the bacteria can attack and break down the RovA.

###

Original article: Herbst K, Bujara M, Heroven AK, Opitz W, Weichert M, et al. 2009 Intrinsic Thermal Sensing Controls Proteolysis of Yersinia Virulence Regulator RovA. PLoS Pathog 5(5): e1000435. doi:10.1371/journal.ppat.1000435

Hydrogen protects nuclear fuel in final storage

2009-04-26T21:35:00.000-07:00

An interesting development in nuclear waste management technology

Dr K.S.Parthasarathy

Public release date: 24-Apr-2009
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Contact: Sofie Hebrand
sofie.hebrand@chalmers.se
46-317-728-464
Swedish Research Council
Hydrogen protects nuclear fuel in final storage

When Sweden's spent nuclear fuel is to be permanently stored, it will be protected by three different barriers. Even if all three barriers are damaged, the nuclear fuel will not dissolve into the groundwater, according to a new doctoral dissertation from Chalmers University of Technology in Sweden.

By Midsummer it will be announced where Sweden's spent nuclear fuel will be permanently stored. Ahead of the decision a debate is underway regarding how safe the method for final storage is, primarily in terms of the three barriers that are intended to keep radioactive material from leaking into the surrounding groundwater.

But according to the new doctoral dissertation, uranium would not be dissolved by the water even if all three barriers were compromised.

"This is a result of what we call the hydrogen effect," says Patrik Fors, who will defend his thesis in nuclear chemistry at Chalmers on Friday. "The hydrogen effect was discovered in 2000. It's a powerful effect that was not factored in when plans for permanent storage began to be forged, and now I have shown that it's even more powerful than was previously thought."

The hydrogen effect is predicated on the existence of large amounts of iron in connection with the nuclear fuel. In the Swedish method for final storage, the first barrier consists of a copper capsule that is reinforced with iron. The second barrier is a buffer of bentonite clay, and the third is 500 meters of granite bedrock. Some other countries have chosen to make the first barrier entirely of iron.

It is known that microorganisms and fissure minerals in the rock will consume all the oxygen in the groundwater. If all three barriers were to be damaged, the iron in the capsule would therefore be anaerobically corroded by the water, producing large amounts of hydrogen. In final storage at a depth of 500 meters, a pressure of at least 5 megapascals of hydrogen would be created.

Patrik Fors has now created these conditions in the laboratory and examined three different types of spent nuclear fuel. All of the trials showed that the hydrogen protects the fuel from being dissolved in the water, even though the highly radioactive fuels create a corrosive environment in the water as a result of their radiation. The reason for the protective effect is that the hydrogen prevents the uranium from oxidizing and converting to liquid form.

Furthermore, the hydrogen makes the oxidized uranium that already exists as a liquid in the water shift to a solid state. The outcome was that the amount of uranium found dissolved in the water, after experiments lasting several years, was lower than the natural levels in Swedish groundwater.

"The hydrogen effect will prevent the dissolution of nuclear fuel until the fuel's radioactivity is so low that it need no longer be considered a hazard," says Patrik Fors. The amount of iron in the capsules is so great that it would produce sufficient hydrogen to protect the fuel for tens of thousands of years.

###

Patrik Fors carried out his experiments at the Institute for Transuranium Elements in Karlsruhe, Germany, in a joint project with Chalmers. The institute is operated by the European Commission. The research was also funded by SKB, the Swedish Nuclear Fuel and Waste Management Company.

The dissertation "The effect of dissolved hydrogen on spent nuclear fuel corrosion" will be publicly defended on April 24 at 10 a.m. Place: Hall KE, Chemistry Building, Kemigården 4, Chalmers University of Technology, Gothenburg, Sweden.

For more information, please contact: Patrik Fors, Nuclear Chemistry, Department of Chemical and Biological Engineering, Chalmers University of Technology, Sweden

Tel: +46707-696 334 patrik.fors@chalmers.se

Supervisor: Kastriot Spahiu, Adjunct Professor, Department of Chemical and Biological Engineering, Chalmers University of Technology, Sweden

+468-459 8561 Kastriot.spahiu@skb.se

Inserting catheters without X-rays

2009-03-10T00:04:00.000-07:00

X-ray imaging to locate catheter can be avoided by using MRI but the guide wire must be plastic. The technique to prepare such wire is available now and may be available shortly for use.

K.S.Parthasarathy

Public release date: 9-Mar-2009
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Contact: Adrian Schütte
adrian.schuette@ipt.fraunhofer.de
49-241-890-4251
Fraunhofer-Gesellschaft
Inserting catheters without X-rays

This release is available in German.

Have the patient's coronary vessels, heart valves or myocardial muscle changed abnormally? Doctors can verify this and administer the necessary therapy with the help of a catheter, which is inserted into the body through a small incision in the groin area and pushed to the heart through the vascular system. A metal guide wire inside the catheter serves as a navigational aid. It is pulled and turned by the physician to steer and guide the catheter. At the same time the catheter's position in the vascular system has to be monitored. This task is performed by X-rays, which penetrate the patient and show exactly where the catheter is. The problem with this computer tomography method is that it exposes the patient to quite a high dose of radiation. In addition, a contrast medium has to be injected into the patient's body in order to make the vascular system and the soft tissue visible on the X-ray images.

Researchers at the Fraunhofer Institute for Production Technology IPT in Aachen have now found a way of avoiding both the radiation and the contrast medium. In collaboration with colleagues at Philips and University Hospital Aachen, they have developed a guide wire made of glass-fiber-reinforced plastic. "Because the guide wire is made of plastic the imaging can be performed by magnetic resonance tomography instead of computer tomography," says IPT scientist Adrian Schütte. "This is not possible with metal guide wires as the metal wire acts as an antenna and heats up too much – this would damage the vessels, and could cause proteins to clot." Magnetic resonance tomography has many advantages for doctors and patients. It does not produce ionizing radiation like computer tomography, and soft tissue is clearly visible, so there is no need for a contrast medium.

For the manufacture of the two-meter guide wires the researchers use the pultrusion method, which is the standard procedure for making continuous profiles from glass-fiber-reinforced plastic. "Diameters of half a millimeter or less are required for the guide wires – that's the absolute minimum," explains Schütte. The new guide wires will be presented at the JEC trade fair in Paris (Hall 1, Stand T18) from March 24 to 26 and will be used in hospitals for the first time in the next few months.

###Public release date: 9-Mar-2009
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'Fish technology' draws renewable energy from slow water currents

2008-11-23T05:53:00.000-08:00

A very interesting concept illustrating a new method of generating power from slow-moving ocean and river currents. The estimated cost of this power source is 5.5 cents per kwh. Wind energy costs 6.9 cents a kilowatt hour. Nuclear costs 4.6, and solar power costs between 16 and 48 cents per kilowatt hour depending on the location.

"If we could harness 0.1 percent of the energy in the ocean, we could support the energy needs of 15 billion people.", Michael Bernitsas, a professor in the University of Michigan, Department of Naval Architecture and Marine Engineering, who developed the concept claimed.

K.S.Parthasarathy

Public release date: 21-Nov-2008

Contact: Nicole Casal Moore
ncmoore@umich.edu
734-647-1838
University of Michigan
'Fish technology' draws renewable energy from slow water currents

IMAGE: An artist's illustration of an array of VIVACE converters on the ocean floor.
Click here for more information.

ANN ARBOR, Mich.---Slow-moving ocean and river currents could be a new, reliable and affordable alternative energy source. A University of Michigan engineer has made a machine that works like a fish to turn potentially destructive vibrations in fluid flows into clean, renewable power.

The machine is called VIVACE. A paper on it is published in the current issue of the quarterly Journal of Offshore Mechanics and Arctic Engineering.

VIVACE is the first known device that could harness energy from most of the water currents around the globe because it works in flows moving slower than 2 knots (about 2 miles per hour.) Most of the Earth's currents are slower than 3 knots. Turbines and water mills need an average of 5 or 6 knots to operate efficiently.

VIVACE stands for Vortex Induced Vibrations for Aquatic Clean Energy. It doesn't depend on waves, tides, turbines or dams. It's a unique hydrokinetic energy system that relies on "vortex induced vibrations."

Vortex induced vibrations are undulations that a rounded or cylinder-shaped object makes in a flow of fluid, which can be air or water. The presence of the object puts kinks in the current's speed as it skims by. This causes eddies, or vortices, to form in a pattern on opposite sides of the object. The vortices push and pull the object up and down or left and right, perpendicular to the current.

These vibrations in wind toppled the Tacoma Narrows bridge in Washington in 1940 and the Ferrybridge power station cooling towers in England in 1965. In water, the vibrations regularly damage docks, oil rigs and coastal buildings.

"For the past 25 years, engineers---myself included---have been trying to suppress vortex induced vibrations. But now at Michigan we're doing the opposite. We enhance the vibrations and harness this powerful and destructive force in nature," said VIVACE developer Michael Bernitsas, a professor in the U-M Department of Naval Architecture and Marine Engineering.

Fish have long known how to put the vortices that cause these vibrations to good use. "VIVACE copies aspects of fish technology," Bernitsas said. "Fish curve their bodies to glide between the vortices shed by the bodies of the fish in front of them. Their muscle power alone could not propel them through the water at the speed they go, so they ride in each other's wake."

This generation of Bernitsas' machine looks nothing like a fish, though he says future versions will have the equivalent of a tail and surface roughness a kin to scales. The working prototype in his lab is just one sleek cylinder attached to springs. The cylinder hangs horizontally across the flow of water in a tractor-trailer-sized tank in his marine renewable energy laboratory. The water in the tank flows at 1.5 knots.

Here's how VIVACE works: The very presence of the cylinder in the current causes alternating vortices to form above and below the cylinder. The vortices push and pull the passive cylinder up and down on its springs, creating mechanical energy. Then, the machine converts the mechanical energy into electricity.

Just a few cylinders might be enough to power an anchored ship, or a lighthouse, Bernitsas says. These cylinders could be stacked in a short ladder. The professor estimates that array of VIVACE converters the size of a running track and about two stories high could power about 100,000 houses. Such an array could rest on a river bed or it could dangle, suspended in the water. But it would all be under the surface.

Because the oscillations of VIVACE would be slow, it is theorized that the system would not harm marine life like dams and water turbines can.

Bernitsas says VIVACE energy would cost about 5.5 cents per kilowatt hour. Wind energy costs 6.9 cents a kilowatt hour. Nuclear costs 4.6, and solar power costs between 16 and 48 cents per kilowatt hour depending on the location.

"There won't be one solution for the world's energy needs," Bernitsas said. "But if we could harness 0.1 percent of the energy in the ocean, we could support the energy needs of 15 billion people."

The researchers recently completed a feasibility study that found the device could draw power from the Detroit River. They are working to deploy one for a pilot project there within the 18 months.

###

This work has been supported by the U.S. Department of Energy, the Office of Naval Research, the National Science Foundation, the Detroit/Wayne County Port Autrhority, the DTE Energy Foundation, Michigan Universities Commercialization Initiative, and the Link Foundation. The technology is being commercialized through Bernitsas' company, Vortex Hydro Energy.

The paper is called "VIVACE (Vortex Induced Vibration for Aquatic Clean Energy): A New Concept in Generation of Clean and Renewable Energy from Fluid Flow." Other authors are Naval Architecture and Marine Engineering graduate students Kamaldev Raghavan, Yaron Ben-Simon and Elizabeth M.H. Garcia.

For more information:
Michael Bernitsas: http://www.engin.umich.edu/dept/name/faculty_staff/bernitsas/Main.htm
Vortex Hydro Energy: http://www.vortexhydroenergy.com/

Michigan Engineering: The University of Michigan College of Engineering is ranked among the top engineering schools in the country. At more than $130 million annually, its engineering research budget is one of largest of any public university. Michigan Engineering is home to 11 academic departments and a National Science Foundation Engineering Research Center. The college plays a leading role in the Michigan Memorial Phoenix Energy Institute and hosts the world class Lurie Nanofabrication Facility. Find out more at http://www.engin.umich.edu/.

EDITORS: Watch and link to a video at: http://www.ns.umich.edu/podcast/video.php?id=499
Photos are available at http://www.ns.umich.edu/htdocs/releases/story.php?id=6841

Magic solar milestone reached

2008-10-24T00:46:00.000-07:00

Solar voltaic cell has achieved the highest efficiency of 25 %. Credit for this goes to the researchers at the University of South Wales (UNSW)'s ARC Photovoltaic Centre of Excellence.

K.S.Parthasarathy

Contact: Peter Trute
p.trute@unsw.edu.au
61-293-851-933
University of New South Wales
Magic solar milestone reached
UNSW claims 25 percent solar cell efficiency title

UNSW's ARC Photovoltaic Centre of Excellence has again asserted its leadership in solar cell technology by reporting the first silicon solar cell to achieve the milestone of 25 per cent effiency.

The UNSW ARC Photovoltaic Centre of Excellence already held the world record of 24.7 per cent for silicon solar cell efficiency. Now a revision of the international standard by which solar cells are measured, has delivered the significant 25 per cent record to the team led by Professors Martin Green and Stuart Wenham and widened their lead on the rest of the world.

Centre Executive Research Director, Scientia Professor Martin Green, said the new world mark in converting incident sunlight into electricity was one of six new world records claimed by UNSW for its silicon solar technologies.

Professor Green said the jump in performance leading to the milestone resulted from new knowledge about the composition of sunlight.

"Since the weights of the colours in sunlight change during the day, solar cells are measured under a standard colour spectrum defined under typical operational meteorological conditions," he said.

"Improvements in understanding atmospheric effects upon the colour content of sunlight led to a revision of the standard spectrum in April. The new spectrum has a higher energy content both down the blue end of the spectrum and at the opposite red end with, dare I say it, relatively less green."

The recalibration of the international standard, done by the International Electrochemical Commission in April, gave the biggest boost to UNSW technology while the measured efficiency of others made lesser gains. UNSW's world-leading silicon cell is now six per cent more efficient than the next-best technology, Professor Green said. The new record also inches the UNSW team closer to the 29 per cent theoretical maximum efficiency possible for first-generation silicon photovoltaic cells.

Dr Anita Ho-Baillie, who heads the Centre's high efficiency cell research effort, said the UNSW technology benefited greatly from the new spectrum "because our cells push the boundaries of response into the extremities of the spectrum".

"Blue light is absorbed strongly, very close to the cell surface where we go to great pains to make sure it is not wasted. Just the opposite, the red light is only weakly absorbed and we have to use special design features to trap it into the cell," she said.

Professor Green said: "These light-trapping features make our cells act as if they were much thicker than they are. This already has had an important spin-off in allowing us to work with CSG Solar to develop commercial 'thin-film' silicon-on-glass solar cells that are over 100 times thinner than conventional silicon cells."

ARC Centre Director, Professor Stuart Wenham said the focus of the Centre is now improving mainstream production. "Our main efforts now are focussed on getting these efficiency improvements into commercial production," he said. "Production compatible versions of our high efficiency technology are being introduced into production as we speak."

The world-record holding cell was fabricated by former Centre researchers, Dr Jianhua Zhao and Dr Aihua Wang, who have since left the Centre to establish China Sunergy, one of the world's largest photovoltaic manufacturers. "China was the largest manufacturer of solar cells internationally in 2007 with 70 per cent of the output from companies with our former UNSW students either Chief Executive Officers or Chief Technical Officers", said Professor Green.

###

Media Contact: Professor Martin Green | 9385 4018 | 0411 492 416 | m.green@unsw.edu.au

UNSW Media Office: Peter Trute | 02 9385 1933 | 0410 271 826 | p.trute@unsw.edu.au

Hydrogen sulfide discovered to be a major player in the regulation of blood pressure

2008-10-23T21:22:00.000-07:00

This news item reveals how intricate and complicated are the biochemical mechanisms which control and keep in harmony various processes in our body.

K.S.Parthasarathy

The heart.org

http://www.theheart.org/viewArticle.do?primaryKey=913773&nl_id=tho23oct08

HEARTWIRE

Hydrogen sulfide discovered to be a major player in the regulation of blood pressure
October 23, 2008 | Michael O'Riordan
Baltimore, MD - Twenty years after US scientists won the Nobel Prize for discovering that nitric oxide (NO) is an important signaling molecule in the cardiovascular system, findings that helped identify the determinants of blood pressure, new research has uncovered yet another gas, hydrogen sulfide (H2S), that acts as a major physiologic vasodilator and regulator of blood pressure.
"Nitric oxide is unique in that it's a gas, and since mediators in the body come in chemical classes, others have wondered whether other gases could do the same sort of thing," said Dr Solomon Snyder (Johns Hopkins University School of Medicine, Baltimore, MD), one of the investigators from the study published in the October 24, 2008 issue of Science.
Made by bacteria in the intestine, H2S has been known for some time to lower blood pressures in animals injected with the gas. Investigators, however, wanted to determine the exact role of H2S as a physiologic vasorelaxant and determinant of blood-pressure levels. Speaking with heartwire, Snyder explained that researchers, including senior investigator Dr Rui Wang (Lakehead University, Thunder Bay, ON), speculated H2S might be made by cystathionine -lyase (CSE), leading to the development of a mouse model in which the gene for CSE was knocked out.
Once the gene for CSE was depleted, the researchers discovered that H2S levels in the serum, heart, aorta, and other tissues were markedly reduced.
"We discovered that in most of the body, except for the brain, hydrogen-sulfide production vanished in the knockout mice," said Solomon. "So we said, 'Aha!' We were then able to characterize these mice to see what changed about them, and of course, the first big question was: Does anything happen to the blood pressure? Sure enough, their blood pressure is markedly elevated, at least as much, if not more so, in mice in which we knock out the gene for making nitric oxide."
Compared with normal mice, blood pressure in the mutant mice peaked at 135 mm Hg when the mice were 12 weeks of age, almost 18 mm Hg higher than in the control mice.
Next steps involved testing how the mesenteric arteries of the mutant mice responded to methacholine, a neurotransmitter that is part of the relaxation pathway. When methacholine was added to the vessels of normal mice, the arteries relaxed. When it was added to the vessels of CSE-knockout mice, however, there was no relaxation of the mesenteric arteries.
"We're going to have to do a lot of work, in lots of blood vessels, and in lots of species of animals, to pin down the relative importance of nitric oxide and hydrogen sulfide, but from our work it is very clear that hydrogen sulfide is a pretty major determinant of how your blood vessels function and your blood pressure," said Snyder.
Although the two gases appear to perform similar functions, Snyder said they are unsure if nitric oxide and H2S work together or are mutually exclusive, a question that will require continued research. In terms of potential long-term clinical implications, H2S could be chemically linked with another molecule, put into a pill, and then released to regulate blood pressure, he added.
Snyder told heartwire the discovery was fascinating and that he could hardly believed the results worked out. "It was just a theory, and we kept doing lots of different experiments, with Rui Wang's lab and with my own lab, and every experiment kept coming out positive. In good science, you do all sorts of experiments to disprove your hypothesis, but nothing disproved this one."
Source
1. Yang G, Wu L, Jiang B, et al. H2S as a physiologic vasorelaxant: hypertension in mice with deletion of cystathionine -lyase. Science 2008; 322:587-590.

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Scientists identify gene that may contribute to improved rice yield

2008-09-30T02:43:00.000-07:00

Public release date: 28-Sep-2008

Contact: Barbara K. Kennedy
science@psu.edu
814-863-4682
Penn State
Scientists identify gene that may contribute to improved rice yield
The researchers created transgenic lines of rice (G-2 and G-8) in which the GIF1 gene was overexpressed.

A team of scientists, including Penn State Distinguished Professor of Biology Hong Ma, has identified a gene in rice that controls the size and weight of rice grains. The gene may prove to be useful for breeding high-yield rice and, thus, may benefit the vast number of people who rely on this staple food for survival. "Our work shows that it is possible to increase rice's yield by enhancing the expression of a particular gene," said Ma. The team's results will be published on 28 September 2008 in an early online edition of the journal Nature Genetics, and in the November print issue of the journal.

The researchers first searched for and identified mutant strains of rice that exhibited underweight grains. "We found a particular mutant that is defective in its ability to produce normal-sized grains," said Zuhua He, a biology professor at the Chinese Academy of Sciences and the leader of the team. The group then examined the mutant and found that it carried a mutation within the GIF1 gene. "The GIF1 gene is responsible for controlling the activity of the enzyme invertase, which is located in the cell wall and converts sucrose to substances that then are used to create starch," said He. "Invertase is important in the formation of starch within developing grains of rice. If invertase is not active, the rice plant cannot produce edible grains."

Next, to test the ability of the GIF1 gene to control the production of invertase, the team measured the activity of invertase within a normal strain of rice, in which the GIF1 gene lacked any mutations, and within a mutant strain of rice, in which the GIF1 gene contained a mutation that caused a defect in the invertase activity. The scientists found that invertase activity in the mutant strain was only 17 percent of the activity that was observed in the normal strain, suggesting that the GIF1 gene does, indeed, control invertase activity. The team then created transgenic lines of rice in which the GIF1 gene is overexpressed and found that, compared with normal strains, the transgenic rice had larger and heavier grains.

According to Ma, the team was surprised to find that the GIF1 gene was so specialized in controlling invertase activity in a particular part of the grain -- the vascular tissue, which transports nutrients, including sugars generated by invertase, to the developing grain. "The expression pattern was not expected, in part, because invertase is a general enzyme that is used by many cell types. In fact, the corresponding gene in wild rice is not expressed specifically."

The team also found that the GIF1 gene is one of the genes that were selected during the domestication of rice. "By selectively growing only those strains of rice with heavier grains, humans for thousands of years unknowingly have been increasing the frequency of rice populations that had modifications in the GIF1 gene," said Ma. "This process has caused GIF1 to be expressed specifically in the vascular tissue and, thus, to produce larger rice grains," said Ma.

The scientists hope that their findings will help others to create hybrid varieties of rice that produce even larger grains. In the meantime, they plan to perform additional analyses that will help them to understand how other genes might be involved in the process of improving rice yield. "The goal is to understand what controls grain weight and other factors, and to look for ways to increase yield," said Ma.

###

This research was supported by grants from the Ministry of Science and Technology of China, the National Science Foundation of China, and the Shanghai Institutes for Biological Sciences.

[ Sara LaJeunesse ]

CONTACTS
Hong Ma: (+1) 814-863-6414, hxm16@psu.edu
Zuhua He: zhhe@sibs.ac.cn
Barbara Kennedy (PIO): (+1) 814-863-4682, science@psu.edu

IMAGE
A high-resolution image related to this story is on the Web at: http://www.science.psu.edu/alert/Ma9-2008.htm
After the embargo lifts, image captions and the text of this press release will be posted there, as well. For your convenience in preparing your stories in advance of the embargo date, the image caption is provided below:

CAPTION AND CREDIT FOR IMAGE:
The researchers created transgenic lines of rice (G-2 and G-8) in which the GIF1 gene was overexpressed. Compared to normal strains (WT), they found that the transgenic rice had larger and heavier grains. In this figure, the grains on the top are from white rice and the grains on the bottom are from brown rice.
Credit: Zuhua He, Chinese Academy of Sciences

Idaho National Laboratory researchers meet major hydrogen milestone

2008-09-20T00:50:00.000-07:00

Idaho National Laboratory reports this week a notable achievement in hydrogen producing technology.

K.S.Parthasarathy

Public release date: 18-Sep-2008

Contact: Teri Ehresman
Teri.Ehresman@inl.gov
208-520-6252
DOE/Idaho National Laboratory
Idaho National Laboratory researchers meet major hydrogen milestone

A team of scientists from the U.S. Department of Energy's Idaho National Laboratory earlier this month reached a major milestone with the successful production of hydrogen through High-Temperature Electrolysis (HTE).

The milestone was reached when the Integrated Laboratory Scale experiment started producing hydrogen at a rate of 5.6 cubic meters per hour.

The achievement was recognized at a media event in Idaho Falls Sept. 18.

"This is by far the biggest achievement we've had," said Carl Stoots, the experiment's principal investigator.

High-Temperature Electrolysis is a system of producing hydrogen very efficiently by using technology originally developed for solid oxide fuel cells. HTE is a significant improvement over the more conventional methods to produce hydrogen. HTE uses an electric current through water to separate it into hydrogen and oxygen. Combined with a clean power source such as a next-generation nuclear plant, HTE could produce hydrogen at 45 to 55 percent efficiency.

There are several potential applications of hydrogen from high-temperature electrolysis, all of which are closer to being actualized now that HTE has proven itself capable of producing hydrogen at such an advanced level. Hydrogen is commonly used to help produce liquid fuels. INL Laboratory Fellow Steve Herring, who heads the HTE project, said it could also prove helpful in upgrading fuel from the Athabasca Tar Sands in Alberta, Canada, because producing gasoline and diesel fuel from such heavy oil deposits requires extensive amounts of hydrogen and steam.

September's achievement is a major scale-up from earlier INL experiments on a small scale. Herring said his team wanted it to match the final product closely.

With this milestone met, the HTE plant is on its way to opening many doors for innovation in energy production, contributing to the Department of Energy's overarching goal of a "hydrogen economy." Eventually, HTE could provide pure hydrogen for fuel cell-powered cars, Herring said – "but that's a long way off."

###

The HTE plant is located in the Bonneville County Technology Center, 101 Technology Drive in Idaho Falls, across the street from the INL Research Center.

Study shows pine bark naturally reduces knee osteoarthritis

2008-09-07T23:55:00.000-07:00

Public release date: 3-Sep-2008

Contact: Melanie Nimrodi
mnimrodi@mww.com
312-546-3508

MWW Group
Study shows pine bark naturally reduces knee osteoarthritis
Third clinical trial reconfirms strong evidence pycnogenol lowers joint pain, symptoms; May now have lasting effect on joints following cessation of the extract

According to the Center for Disease Control (CDC), osteoarthritis, the most common type of arthritis, is on the rise. A new study published in the August journal of Phytotherapy Research, reveals Pycnogenol, bark extract from the French maritime pine tree, reduced overall knee osteoarthritis (OA) symptoms by 20.9 percent and lowered pain by 40.3 percent. To date, this is the third clinical trial on osteoarthritis treatment with Pycnogenol. This study investigated what happens to joint symptoms after treatment with Pycnogenol is terminated and the results show that no relapse occurred after two weeks. Pycnogenol acts as potent anti-inflammatory and the lasting effects found in this study suggest that Pycnogenol may help the joints to recover.

With osteoarthritis cases on the rise, many are seeking non-traditional medication to help ease the pain and reduce the amount of traditional medication taken. The CDC estimates osteoarthritis affects 34 percent of all adults over the age of 65. In 2005, an estimated 26.9 million adults in the U.S. had osteoarthritis, which was up from 21 million in 1990. While there's no known cure for osteoarthritis, treatments such as nonsteroidal anti-inflammatory drugs (NSAIDs) or analgesics can help reduce pain and also maintain joint movement, to help the quality of life for people living with the disease. In more severe cases, cortisone shots and joint replacement surgery are used to treat OA.

"The current study is in accordance with the two previous Pycnogenol studies for osteoarthritis," said Dr. Peter Rohdewald, one of the researchers of the study. "Again the pain is gradually decreasing during the course of three months treatment with Pycnogenol. An improvement is found after the first month and a further improvement is seen after two months, where values are significantly different to the placebo group. This study again showed that patients required significantly less analgesic medication while supplementing with Pycnogenol, whereas this was not the case with the placebo-treated control group."

The study was held at Slovakia's Comenius University School of Medicine. One hundred patients with stage I or II OA were included in the study and were randomly allocated to either a Pycnogenol or placebo group. Patients were supplemented with 150 mg Pycnogenol or placebo per day over a period of three months. They were allowed to continue taking their NSAID or analgesics prescribed before the study but had to record every pill taken. The established Western Ontario McMaster questionnaire for joint function was employed to rate the pain level, and obtain measures of joint stiffness and to what extent the arthritis affects participation in daily activities. Patients were investigated in two week intervals over the treatment period of three months and a final time two weeks after discontinuation of medication.

The overall score, summarizing pain, stiffness and daily activities, improved statistical significantly by 20.9 percent in the Pycnogenol group. Interestingly, the joint improvement achieved with Pycnogenol persisted after intake of Pycnogenol was discontinued for four weeks. The joint pain decreased by 40.3 percent after completion of the three months supplementation with Pycnogenol and two weeks later the pain was still 36.1 percent lower than at baseline. Furthermore, 38 percent of patients in the Pycnogenol group required less NSAID's or other analgesic medication for joint pain.

"The anti-inflammatory potency of Pycnogenol explains the success in lowering joint pain and stiffness for arthritic joints," said Rohdewald. "After three recent clinical studies on osteoarthritis, Pycnogenol continues to demonstrate its effectiveness for osteoarthritis symptoms making it a viable, natural and safe alternative for individuals. This is the first study that investigated whether a relapse of symptoms occurs after taking Pycnogenol is stopped. The results show a lasting effect after discontinuation which suggest the anti-inflammatory mechanisms of Pycnogenol has allowed the joints to recover."

In another study this year (also published in the journal of Phytotherapy Research), Pycnogenol was shown to reduce osteoarthritis symptoms by 56 percent. Moreover, patients required 58 percent less standard pain medication, which greatly improved the gastrointestinal complications resulting from the pain medication by 63 percent. Last year, a study on osteoarthritis carried out at the University of Arizona Tucson (published in Nutrition Research) discovered that Pycnogenol was effective for improving pain and joint function. After three months in the Pycnogenol group, there was a reduction of 43 percent in pain, 35 percent in stiffness and 52 percent in physical function subscales, respectively. The placebo group showed no significant scores throughout the entire study.

###

Horphag Research, the exclusive worldwide distributor of Pycnogenol has filed for several patents for Pycnogenol's application for COX-1 and COX-2 inhibition and treatment of osteoarthritis.

About Pycnogenol®

Pycnogenol® is a natural plant extract originating from the bark of the maritime pine that grows along the coast of southwest France and is found to contain a unique combination of procyanidins, bioflavonoids and organic acids, which offer extensive natural health benefits. The extract has been widely studied for the past 35 years and has more than 220 published studies and review articles ensuring safety and efficacy as an ingredient. Today, Pycnogenol® is available in more than 600 dietary supplements, multi-vitamins and health products worldwide. For more information, visit www.pycnogenol.com.

Natural Health Science Inc. (NHS), based in Hoboken, New Jersey, is the North American distributor for Pycnogenol® (pic-noj-en-all) brand French maritime pine bark extract on behalf of Horphag Research. Pycnogenol® is a registered trademark of Horphag Research Ltd., Guernsey, and its applications are protected by U.S. patents #5,720,956 / #6,372,266 and other international patents. NHS has the exclusive rights to market and sell Pycnogenol® in North America and benefits from more than 35 years of scientific research assuring the safety and efficacy of Pycnogenol® as a dietary supplement. For more information about Pycnogenol® visit our Web site at www.pycnogenol.com.

Researchers discover atomic bomb effect results in adult-onset thyroid cancer

2008-08-29T00:50:00.000-07:00

Public release date: 29-Aug-2008

Contact: Jeremy Moore
Jeremy.moore@aacr.org
267-646-0557
American Association for Cancer Research
Researchers discover atomic bomb effect results in adult-onset thyroid cancer

PHILADELPHIA – Radiation from the atomic bomb blasts in Hiroshima and Nagasaki, Japan, in 1945, likely rearranged chromosomes in some survivors who later developed papillary thyroid cancer as adults, according to Japanese researchers.

In the September 1, 2008, issue of Cancer Research, a journal of the American Association for Cancer Research, the scientists report that subjects who lived close to the blast sites, were comparably young at the time, and developed the cancer quickly once they reached adulthood, were likely to have a chromosomal rearrangement known as RET/PTC that is not very frequent in adults who develop the disease.

"Recent in vitro and in vivo studies suggest that a single genetic event in the MAP kinase-signaling pathway may be sufficient for thyroid cell transformation and tumor development," said the study's lead author, Kiyohiro Hamatani, Ph.D., laboratory chief, Department of Radiobiology and Molecular Epidemiology at the Radiation Effects Research Foundation (RERF) in Hiroshima.

"Thyroid cancer is associated with exposure to external or internal ionizing radiation.Elucidation of mechanisms of radiation-induced cancer in humans, especially early steps and pathways, has potential implications for epidemiological risk analyses, early clinical diagnosis, and chemopreventive interventions," Hamatani said.

He adds that there are several irradiated populations worldwide that have been shown to have an increase in thyroid cancer, and that children exposed to radioactive fallout from the 1986 Chernobyl nuclear power plant accident who develop papillary thyroid cancer have also been found to have RET/PTC rearrangements, although they are slightly different.

This study is part of the foundation's long running follow-up research on 120,000 atomic bomb survivors. During 1958 to 1998, the study found about 470 thyroid cancer cases of which the estimated number of excess cases attributable to radiation is 63. About 90 percent of thyroid cancer among the survivors is of the papillary type.

Hamatani and colleagues from across Japan made a comparison between adult-onset papillary thyroid cancers with RET/PTC rearrangements and those with a BRAF mutation. More than 70 percent of adult onset papillary thyroid cancer in non-exposed patients is associated with mutations in the BRAF gene.

The researchers looked at the genetic profile of cancer patients in the RERF's follow-up study--50 patients who were exposed to atomic bomb radiation and 21 patients who were not. Three factors were found to be independently associated with the development of adult-onset papillary thyroid cancer with RET/PTC rearrangements. They were greater radiation dose, shorter time elapsed since radiation exposure, and younger age at the time of the bombings, Hamatani says.

"That means that a younger person living close to the bombing site would be more likely to have adult onset thyroid cancer having RET/PTC rearrangements," he said. "This is the first time this has been shown."

The findings also suggest that in childhood papillary thyroid cancer RET/PTC rearrangements may be much less clearly associated with radiation exposure, compared with adult-onset cancer, because RET/PTC rearrangements are frequent in childhood papillary thyroid cancer patients regardless of history of radiation exposure.

The researchers do not know exactly how radiation is involved in the occurrence of RET/PTC rearrangements. "It could be either by direct DNA damage or by other pathways such as a result of radiation-induced genomic instability," Hamatani said.

###

The mission of the American Association for Cancer Research is to prevent and cure cancer. Founded in 1907, AACR is the world's oldest and largest professional organization dedicated to advancing cancer research. The membership includes more than 28,000 basic, translational and clinical researchers; health care professionals; and cancer survivors and advocates in the United States and 80 other countries. AACR marshals the full spectrum of expertise from the cancer community to accelerate progress in the prevention, diagnosis and treatment of cancer through high-quality scientific and educational programs. It funds innovative, meritorious research grants. The AACR Annual Meeting attracts more than 17,000 participants who share the latest discoveries and developments in the field. Special conferences throughout the year present novel data across a wide variety of topics in cancer research, treatment and patient care. AACR publishes five major peer-reviewed journals: Cancer Research; Clinical Cancer Research; Molecular Cancer Therapeutics; Molecular Cancer Research; and Cancer Epidemiology, Biomarkers & Prevention. Its most recent publication and its sixth major journal, Cancer Prevention Research, is dedicated exclusively to cancer prevention, from preclinical research to clinical trials. The AACR also publishes CR, a magazine for cancer survivors and their families, patient advocates, physicians and scientists. CR provides a forum for sharing essential, evidence-based information and perspectives on progress in cancer research, survivorship and advocacy.

Researchers find high levels of toxic metals in herbal medicine products sold online

2008-08-28T21:23:00.000-07:00

This paper is similar to the one published by the lead author and his colleagues in JAMA in 2005.I have followed it up with a feature article in the PTIFEATURE published by the Press Trust of India, the premier news agency of India

K.S.Parthasarathy

Public release date: 26-Aug-2008

Contact: Michelle Roberts
michelle.roberts@bmc.org
617-638-8491
Boston University
Researchers find high levels of toxic metals in herbal medicine products sold online

Boston, MA--Researchers at Boston University School of Medicine (BUSM) have found that one fifth of both U.S.-manufactured and Indian-manufactured Ayurvedic medicines purchased via the Internet contain lead, mercury or arsenic. These findings appear in the August 27th issue of the Journal of the American Medical Association (JAMA).

Ayurveda is a form of medicine that originated in India more than 2,000 years ago and relies heavily on herbal products. In India, an estimated 80 percent of the population practices Ayurveda. In the United States, Ayurvedic remedies have increased in popularity and are available from South Asian markets, health food stores, and on the Internet. Ayurvedic medicines are divided into two major types: herbal only and rasa shastra. Rasa shastra is an ancient practice of deliberately combining herbs with metals, minerals and gems. Ayurvedic experts in India believe that if Rasa Shastra medicines made with metals such as lead and mercury are properly prepared and administered, they will be safe and therapeutic.

Using an Internet search, the researchers identified 25 Web sites featuring 673 Ayurvedic medicines. They randomly selected and purchased 193 products made by 37 different manufacturers for analyses. Overall, 20.7 percent of Ayurvedic medicines contained detectable lead, mercury and/or arsenic. U.S. and Indian manufactured products were equally likely to contain toxic metals. Rasa shastra compared with non-rasa shastra medicines were more than twice as likely to contain metals and had higher concentrations of lead and mercury. Among products containing metals, 95 percent were sold by U.S. Web sites and 75 percent claimed Good Manufacturing Practices or testing for heavy metals. All metal-containing products exceeded one or more standards for acceptable daily intake of toxic metals.

"This study highlights the need for Congress to revisit the way dietary supplements are regulated in the U.S.," said lead author Robert Saper, MD, MPH, Director of Integrative Medicine in the Family Medicine Department at BUSM. Saper first published on this topic in December, 2004 (JAMA). In that study he and his colleagues found 20% of Ayurvedic medicines produced in South Asia only and available in Boston area stores contained potentially harmful levels of lead, mercury, and/or arsenic. "Our first priority must be the safety of the public. Herbs and supplements with high levels of lead, mercury, and arsenic should not be available for sale on the Internet or elsewhere," he said.

Saper adds, "We suggest strictly enforced, government mandated daily dose limits for toxic metals in all dietary supplements and requirements that all manufacturers demonstrate compliance through independent third-party testing."

"The medicines which are supposed to cure sickness should not promote another illness due to the presence of toxic materials such as lead," said co-author Venkatesh Thuppil, PhD, Director of the National Referral Centre for Lead Poisoning in India, as well as a Professor at St. John's Medical College in India.

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Biochemists manipulate fruit flavor enzymes

2008-08-24T23:24:00.000-07:00

Public release date: 20-Aug-2008
Contact: Robert Cahill
Robert.Cahill@uth.tmc.edu
713-500-3042
University of Texas Health Science Center at Houston
Biochemists manipulate fruit flavor enzymes

Would you like a lemony watermelon? How about a strawberry-flavored banana? Biochemists at The University of Texas Medical School at Houston say the day may be coming when scientists will be able to fine tune enzymes responsible for flavors in fruits and vegetables. In addition, it could lead to environmentally-friendly pest control.

In the advance online publication of Nature on Aug. 20, UT Medical School Assistant Professor C.S. Raman, Ph.D., and his colleagues report that they were able to manipulate flavor enzymes found in a popular plant model, Arabidopsis thaliana, by genetic means. The enzymes—allene oxide synthase (AOS) and hydroperoxide lyase (HPL)—produce jasmonate (responsible for the unique scent of jasmine flowers) and green leaf volatiles (GLV) respectively. GLVs confer characteristic aromas to fruits and vegetables.

Green leaf volatiles and jasmonates emitted by plants also serve to ward off predators. "Mind you plants can't run away from bugs and other pests. They need to deal with them. One of the things they do is to release volatile substances into the air so as to attract predators of the bugs," Raman said.

"Genetic engineering/modification (GM) of green leaf volatile production holds significant potential towards formulating environmentally friendly pest-control strategies. It also has important implications for manipulating food flavor," said Raman, the senior author. "For example, the aroma of virgin olive oil stems from the volatiles synthesized by olives. By modifying the activity of enzymes that generate these substances, it may be possible to alter the flavor of the resulting oils."

According to Raman, "Our work shows how you can convert one enzyme to another and, more importantly, provides the needed information for modifying the GLV production in plants." The scientists made 3-D images of the enzymes, which allowed them to make a small, but specific, genetic change in AOS, leading to the generation of HPL.

AOS and HPL are part of a super family of enzymes called cytochrome P450. P450 family enzymes are found in most bacteria and all known plants and animals. Although AOS or HPL are not found in humans, there are related P450 family members that help metabolize nearly half of the pharmaceuticals currently in use. In plants, AOS and HPL break down naturally-occurring, organic peroxides into GLV and jasmonate molecules. "Each flavor has a different chemical profile," Raman said.

"A notable strength of this manuscript is the combined use of structural and evolutionary biology to draw new insights regarding enzyme function. These insights led to the striking demonstration that a single amino acid substitution converts one enzyme into another, thereby showing how a single point mutation can contribute to the evolution of different biosynthetic pathways. This begins to answer the long-standing question as to how the same starting molecule can be converted into different products by enzymes that look strikingly similar," said Rodney E. Kellems, Ph.D., professor and chairman of the Department of Biochemistry & Molecular Biology at the UT Medical School at Houston.

The study dispels the earlier view that these flavor-producing enzymes are only found in plants, Raman said. "We have discovered that they are also present in marine animals, such as sea anemone and corals. However, we do not know what they do in these organisms."

###

The study is titled "Structural insights into the evolutionary paths of oxylipin biosynthetic enzymes." The lead authors were Dong-Sun Lee, Ph.D., an assistant professor in the Department of Biochemistry & Molecular Biology at the UT Medical School at Houston, and Pierre Nioche, Ph.D., an assistant professor at the Université Paris Descartes. Mats Hamberg, M.D., Ph.D., professor of medical chemistry in the Division of Physiological Chemistry, Karolinska Institutet, Stockholm, Sweden, collaborated on the research.

The research is supported by Pew Charitable Trusts through a Pew Scholar Award, The Robert A. Welch Foundation, The National Institutes of Health, a Beginning Grant in Aid from the American Heart Association, and an INSERM Avenir Grant sponsored by La Fondation pour la Recherche Medicale.

Water refineries

2008-08-01T02:44:00.000-07:00

Public release date: 31-Jul-2008
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Contact: Josh Chamot
jchamot@nsf.gov
703-292-7730
National Science Foundation
Water refineries?
New method extracts oxygen from water with minimal energy, potentially boosting efforts to develop solar as a 24-hour energy source
A snapshot showing the new, efficient oxygen catalyst in action in Dan Nocera's laboratory at MIT.
Click here for more information.

Using a surprisingly simple, inexpensive technique, chemists have found a way to pull pure oxygen from water using relatively small amounts of electricity, common chemicals and a room-temperature glass of water.

Because oxygen and hydrogen are energy-rich fuels, many researchers have proposed using solar electricity to split water into those elements--a stored energy source for when the sun goes down. One of the chief obstacles to that green-energy scenario has been the difficulty of producing oxygen without large amounts of energy or a high-maintenance environment.

Now, Massachusetts Institute of Technology chemist Daniel Nocera and his postdoctoral student Matthew Kanan have discovered an efficient way to solve the oxygen problem. They announced their findings July 31, 2008, online in the journal Science.

"The discovery has enormous implications for the large scale deployment of solar since it puts us on the doorstep of a cheap and easily manufactured storage mechanism," said Nocera. "The ease of implementation means that this discovery will have legs. I have great faith in my chemistry, materials science and engineering colleagues in the community to drive this discovery hard and hopefully their work, along with our continued studies will yield viable technologies within 10 years."

While a home-based energy source using this technique could be a decade away, the breakthrough is a major step forward.

"This study demonstrates how research is critical for driving American competitiveness in the global energy marketplace. By funding fundamental research in water and renewable energy, we are investing in both our economic and environmental futures," said Arden L. Bement, Jr., director of the National Science Foundation (NSF).

To produce oxygen, Nocera and Kanan added cobalt and phosphates to neutral water and then inserted a conductive-glass electrode. As soon as the researchers applied a current, a dark film began to form on the electrode from which tiny pockets of oxygen began to appear, eventually building into a stream of bubbles.

After analyzing the electrode, the researchers concluded that a cobalt-phosphate mixture, possibly combined with phosphate, had deposited as a film.

Nocera and Kanan believe the film is the catalyst that helps break apart the water molecules to create oxygen gas. The protons (hydrogen nuclei) released from the process pick up electrons and convert back into hydrogen at a partner electrode.

Nocera and Kanan also found evidence that the catalyst seems to refresh itself, a mechanism that would make maintenance of such oxygen-extracting systems far simpler than alternatives, although that finding needs confirmation from additional experiments.

"The simplicity of this process is amazing," said Luis Echegoyen, director of NSF's Chemistry Division. "Using common and affordable elements, and a glass of water, these chemists may have given us a future way to efficiently obtain oxygen by splitting water."

Despite the straightforward experimental setup, the exact mechanism driving the reactions is still unknown. For direct conversion of solar energy into hydrogen and oxygen, researchers will need to study the new research results and incorporate the mechanisms into a larger system that also cleanly produces hydrogen.

Nocera is a member of NSF's Powering the Planet, a partnership that NSF forged between MIT, Caltech and several other institutions as an NSF Chemical Bonding Center in 2005. In his role as a co-investigator with the center, Nocera has been pursuing sustainable energy technology through a broader effort to learn from, and apply, the lessons of photosynthesis and other natural processes.

"When we support fundamental research we never know where that investment will lead. In this instance, it may lead to new opportunities for sustainable energy," said Tony Chan, assistant director for NSF's Mathematics and Physical Sciences Directorate.

###

FDA Preliminary1 Public Health Notification: Possible Malfunction of Electronic Medical Devices Caused by Computed Tomography (CT) Scanning

2008-07-17T22:17:00.000-07:00

USFDA has issued a very important preliminary notification on possible malfunction of medical devices caused by CT scanning.The number of patients who carry medical devices in India is not known. Since such devices are very expensive the patients carrying them may be very few. According to sun-sentinel.com, in US,tens of millions of patients are outfitted with these technologies, which use electrical currents to help various organs overcome functional deficits.

K.S.Parthasarathy

FDA Preliminary1 Public Health Notification: Possible Malfunction of Electronic Medical Devices Caused by Computed Tomography (CT) Scanning

Date July 14, 2008
Dear Healthcare Professional:
This is to alert you to the possibility that the x-rays used during CT examinations may cause some implanted and external electronic medical devices to malfunction, and to provide recommendations to reduce the potential risk.

Most patients with electronic medical devices undergo CT scans without any adverse consequences. However, FDA has received a small number of reports of adverse events in which CT scans may have interfered with electronic medical devices, including pacemakers, defibrillators, neurostimulators, and implanted or externally worn drug infusion pumps. There have been similar reports in the literature.2-4
It is possible that this interference is being reported more frequently now because of the increased utilization of CT, the higher dose-rate capability of newer CT machines, an increase in the number of patients with implanted and externally worn electronic medical devices, and better reporting systems.
We are continuing to investigate this issue while working with device manufacturers and raising awareness in the healthcare community. To date, no patient deaths have been reported from CT scanning of implanted or externally worn electronic medical devices.
Adverse events
In the reports received by FDA, the following adverse events were likely to have been caused by x-rays from CT scans:
• Unintended “shocks” (i.e., stimuli) from neurostimulators
• Malfunctions of insulin infusion pumps
• Transient changes in pacemaker output pulse rate
Note that malfunctions of this kind, which can result from direct exposure of the medical device to the high x-ray dose rates generated by some CT equipment, are different from those related to MRI scanning, which are caused by strong electric and magnetic fields.
Recommendations
Before beginning a CT scan, the operator should use CT scout views to determine if implanted or externally worn electronic medical devices are present and if so, their location relative to the programmed scan range.
For CT procedures in which the medical device is in or immediately adjacent to the programmed scan range, the operator should:
• Determine the device type;
• If practical, try to move external devices out of the scan range;
• Ask patients with neurostimulators to shut off the device temporarily while the scan is performed;
• Minimize x-ray exposure to the implanted or externally worn electronic medical device by:
o Using the lowest possible x-ray tube current consistent with obtaining the required image quality; and
o Making sure that the x-ray beam does not dwell over the device for more than a few seconds;
Important note: For CT procedures that require scanning over the medical device continuously for more than a few seconds, as with CT perfusion or interventional exams, attending staff should be ready to take emergency measures to treat adverse reactions if they occur.
After CT scanning directly over the implanted or externally worn electronic medical device:
• Have the patient turn the device back on if it had been turned off prior to scanning.
• Have the patient check the device for proper functioning, even if the device was turned off.
• Advise patients to contact their healthcare provider as soon as possible if they suspect their device is not functioning properly after a CT scan.
Background
Experimental studies with anthropomorphic phantoms have demonstrated the potential for high dose rate CT irradiation to affect implanted cardiac rhythm management devices.3,4 Some occurrences in patients, which involved neurostimulator and pacemaker devices, have also been reported to FDA and appear in the literature.3,5
Electronic medical devices that theoretically could be affected by CT x-rays include, but are not limited to:
• cardiac pacemakers,
• implantable cardiac defibrillators,
• neurostimulators,
• drug infusion pumps, including insulin pumps,
• cochlear implants, and
• retinal implants.
While theoretically possible, reports of CT interference with cochlear implants and retinal implants have not been received to date.
Problems with electronic medical devices that might be caused by CT scanner interference include:
• generation of spurious signals, including cardiac defibrillation pulses
• misinterpretation of signals produced by the x-rays as actual biological signals
• missed detection of actual biological signals
• resetting or reprogramming of device settings
The type of effect, if any, is likely to depend on the device type, the manufacturer and the model.
Reporting to FDA
FDA requires hospitals and other user facilities to report deaths and serious injuries associated with the use of medical devices. If you suspect that a reportable adverse event was related to the use of CT equipment, you should follow the reporting procedure established by your facility.
We also encourage you to report adverse events that do not meet the requirements for mandatory reporting. You can report directly to MedWatch, the FDA Safety Information and Adverse Event Reporting program. You may submit reports online at www.fda.gov/MedWatch/report.htm, by phone 1-800-FDA-1088, or by returning the postage-paid FDA form 3500 which may be downloaded from www.fda.gov/MedWatch/getforms.htm by mail to MedWatch, 5600 Fishers Lane, Rockville, MD 20852-9787 or fax 1-800-FDA-0178.
Getting More Information
If you have questions about this Notification, please contact Issues Management Staff, Office of Surveillance and Biometrics (HFZ-510), 1350 Piccard Drive, Rockville, Maryland, 20850, by Fax at 240-276-3356, or by e-mail at phann@cdrh.fda.gov. You may also leave a voicemail message at 240-276-3357 and we will return your call as soon as possible.

FDA medical device Public Health Notifications are available on the Internet at http://www.fda.gov/cdrh/safety.html. You can also be notified through email on the day the safety notification is released by subscribing to our list server. To subscribe, visit: http://service.govdelivery.com/service/subscribe.html?code=USFDA_39.
Sincerely yours,

Daniel G. Schultz, MD
Director
Center for Devices and Radiological Health
Food and Drug Administration

1 CDRH Preliminary Public Health Notifications are intended to quickly share device-related safety information with healthcare providers when the available information and our understanding of an issue are still evolving. We will revise this Notification as new information merits and so encourage you to check this site for updates.
2 “Does High-Power Computed Tomography Scanning Equipment Affect the Operation of Pacemakers?,” Yamaji, S., et al., Circulation Journal 70:190-197 (2006).
3 “Effects of CT Irradiation on Implantable Cardiac Rhythm Management Devices,” McCollough, C., et al., Radiology 243 (3):766-774 (2007).
4 “Hazard Report—CT Scans Can Affect the Operation of Implanted Electronic Devices,” ECRI Institute Problem Reporting System, Health Devices 36 (4):136-138 (2007).
5 MedSun is the FDA's Medical Product Safety Network of 350 hospitals spread throughout the United States. Information from 132 of these facilities indicated that they have not experienced any CT medical device interference, while 3 have had from 1 to 3 events that may have been CT scan induced. Fifteen MedSun facilities indicated they take some precautionary steps when CT scanning patients who have electronic medical devices.
Updated July 14, 2008

New electrostatic-based DNA microarray technique could revolutionize medical diagnostics

2008-07-01T03:55:00.000-07:00

U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) has invented a technique in which DNA or RNA assays — the key to genetic profiling and disease detection — can be read and evaluated without the need of elaborate chemical labeling or sophisticated instrumentation. Based on electrostatic repulsion — in which objects with the same electrical charge repel one another — the technique is relatively simple and inexpensive to implement, and can be carried out in a matter of minutes.

The news release is prepared very carefully highlighting areas which are yet to be practically realized into the realm of reality!

K.S.Parthasarathy

Contact: Lynn Yarris
lcyarris@lbl.gov
510-486-5375
DOE/Lawrence Berkeley National Laboratory
New electrostatic-based DNA microarray technique could revolutionize medical diagnostics
DNA microarrays can be easily interrogated with only the naked eye using a new electrostatic imaging technique developed in the laboratory of Jay Groves, a chemist with Berkeley Lab,...
Click here for more information.

BERKELEY, CA — The dream of personalized medicine — in which diagnostics, risk predictions and treatment decisions are based on a patient's genetic profile — may be on the verge of being expanded beyond the wealthiest of nations with state-of-the-art clinics. A team of researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) has invented a technique in which DNA or RNA assays — the key to genetic profiling and disease detection — can be read and evaluated without the need of elaborate chemical labeling or sophisticated instrumentation. Based on electrostatic repulsion — in which objects with the same electrical charge repel one another — the technique is relatively simple and inexpensive to implement, and can be carried out in a matter of minutes.

"One of the most amazing things about our electrostatic detection method is that it requires nothing more than the naked eye to read out results that currently require chemical labeling and confocal laser scanners," said Jay Groves, a chemist with joint appointments at Berkeley Lab's Physical Biosciences Division and the Chemistry Department of the University of California (UC) at Berkeley, who led this research. "We believe this technique could revolutionize the use of DNA microarrays for both research and diagnostics."
A new method for reading DNA (or RNA) microarrays is based on measuring the electrostatic repulsion between silica microspheres and hybridized DNA. Surface areas containing double-stranded DNA (red) or single-stranded...
Click here for more information.

Groves, who is also a Howard Hughes Medical Institute (HHMI) investigator, and members of his research group Nathan Clack and Khalid Salaita, have published a paper on their technique in the journal Nature Biotechnology, which is now available online. The paper is entitled "Electrostatic readout of DNA microarrays with charged microspheres."

In their paper, Groves, Clack, and Salaita describe how dispersing a fluid containing thousands of electrically-charged microscopic beads or spheres made of silica (glass) across the surface of a DNA microarray and then observing the Brownian motion of the spheres provides measurements of the electrical charges of the DNA molecules. These measurements can in turn be used to interrogate millions of DNA sequences at a time. What's more, these measurements can be observed and recorded with a simple hand-held imaging device — even a cell phone camera will do.

"The assumption has been that no detection technique could be more sensitive than fluorescent labeling, but this is completely untrue, as our results have plainly demonstrated," said Groves. "We've shown that changes in surface charge density as a result of specific DNA hybridization can be detected and quantified with 50-picometer sensitivity, single base-pair mismatch selectivity, and in the presence of complex backgrounds. Furthermore, our electrostatic detection technique should render DNA and RNA microarrays sufficiently cost effective for broad world-health applications, as well as research."

Your susceptibility to a given disease and how your body will respond to drugs or other interventions is unique to your genetic makeup. Under a personalized medicine plan, treatment effectiveness is maximized and risks are minimized by tailoring disease treatments specifically to you. This requires the precise diagnostic tests and targeted therapies that can stem from assays using a DNA microarray — a thumbnail-sized substrate containing thousands of microscopic spots of oligonucleotides (stretches of DNA about 20 base pairs in length) laid out in a grid.

Often referred to as "gene chips," DNA microarray assays and their RNA counterparts have become one of the most powerful tools for gene-expression profiling, the identification of mutations, and the detection of multiple pathogens in patients afflicted either by multiple diseases or drug-resistant strains of diseases. Aside from their potential future role in personalized medicine, the widespread use of DNA microarray assay devices could have an immediate and profound impact on the treatment of diseases today. For example, according to a report two years ago from the Global Health Diagnostics Forum, 400,000 lives could be saved each year from death by tuberculosis through the use of DNA microarray assays rather than the standard TB diagnostic test, which is known to miss nearly half of all cases.

Until now, however, the use of DNA microarray assays has been limited because current techniques typically depend upon fluorescence detection, a demanding methodology that requires time-consuming chemical labeling, high-power excitation sources, and sophisticated instrumentation for scanning. Such demands are generally well beyond the capabilities of individual laboratories or clinics, especially in developing countries. While label-free DNA detection strategies do exist, they require either complex device fabrication or sophisticated instrumentation for readouts, and in addition none are compatible with conventional DNA microarrays, where up to one million sequences are available for interrogation in a single experiment.

"We have demonstrated parallel sampling of a microarray surface with micron-scale resolutions over centimeter-scale lengths," said Groves. "This is four orders of magnitude larger than what has been achieved to date with conventional scanning-electrostatic-force microscopy."

In a typical experiment, a microarray is prepared and mounted in a well chamber and the DNA is hybridized (a standard technique in which complementary single strands of DNA bind to form double-stranded DNA "hybrids"). A suspension of negatively-charged silica microspheres is then dispersed through gravitational sedimentation over the microarray surface, a process which takes about 20 minutes. Because the substrate or background surface of the microassay is positively charged, the silica microspheres will spread across the entire surface and adhere to it. However, on surface areas containing double-stranded DNA, which is highly negatively charged, and on areas containing single-stranded DNA, also negatively charged but to a lesser degree than double-stranded DNA, the microspheres will levitate above the substrate surface, stacking up in "equilibrium heights" that are dictated by a balance between gravitational and electrostatic forces.

These electrostatic interactions on the microarray surface result in charge-density contrasts that are readily observed. Surface areas containing DNA segments take on a frosted or translucent appearance, and can be correlated to specific hybridizations that reveal the presence of genes, mutations and pathogens.

"Our technique is essentially a millionfold parallel version of the classic experiment used by Robert Millikan almost 100 years ago, when he determined the charge of a single electron by observing the positions of oil droplets levitated above a charged plate," said Groves.

There are a number of short-term "next steps" for this research, Groves said, including testing its application in high-density arrays and pushing its ultimate resolution limits.

"Since the resolution of electrostatic-based imaging is determined by the number of particle-observations rather than by the diffraction limit of light, our readouts could serve as a form of ultramicroscopy," he said. "The real grand challenge for this technology, however, will be for us to find suitable industrial partners with whom we can work to see that useful new products actually make it to market."

###

The electrostatic detection technology is now available for licensing through Berkeley Lab's Technology Transfer Department; visit their website at http://www.lbl.gov/Tech-Transfer/index.html.

This research was funded by the U.S. Department of Energy's Office of Science through its Office of Basic Energy Sciences.

Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California. Visit our website at www.lbl.gov.

crude 'oil' from pig manure

2008-06-13T23:09:00.000-07:00

Chemists at the US National Institute of Standards and Technology (NIST)have developed a method to make crude oil from pig manure!Not surprising any more as the price of petrol is currently $4 gallon in USA. Pigsty owners will be delighted to supply the "raw material" without any hindrance!The trouble is that "Whatever the pigs eat, from dirt to nutritional supplements, ends up in the oil". Scientists concede.

NIST researchers found that pig manure crude contains at least "83 major compounds, including many components that would need to be removed, such as about 15 percent water by volume, sulfur that otherwise could end up as pollution in vehicle exhaust, and lots of char waste containing heavy metals, including iron, zinc, silver, cobalt, chromium, lanthanum, scandium, tungsten and minute amounts of gold and hafnium".

May be the farmers must subsidize the process to make usable crude from pig manure!

K.S.Parthasarathy

Public release date: 12-Jun-2008

Contact: Laura Ost
laura.ost@nist.gov
303-497-4880
National Institute of Standards and Technology (NIST)
NIST chemists get scoop on crude 'oil' from pig manure
To watch NIST chemist Tom Bruno talk about his research on crude oil made from pig manure, go to http://www.nist.gov/public_affairs/techbeat/tb2008_0610.htm#crude
Click here for more information.

After a close examination of crude oil made from pig manure, chemists at the National Institute of Standards and Technology (NIST) are certain about a number of things.

Most obviously, "This stuff smells worse than manure," says NIST chemist Tom Bruno.

But a job's a job, so the NIST team has developed the first detailed chemical analysis revealing what processing is needed to transform pig manure crude oil into fuel for vehicles or heating. Mass production of this type of biofuel could help consume a waste product overflowing at U.S. farms, and possibly enable cutbacks in the nation's petroleum use and imports. But, according to a new NIST paper,* pig manure crude will require a lot of refining.

The ersatz oil used in the NIST analyses was provided by engineer Yuanhui Zhang of the University of Illinois Urbana-Champaign. Zhang developed a system using heat and pressure to transform organic compounds such as manure into oil.

As described in the new paper, Bruno and colleagues determined that the pig manure crude contains at least 83 major compounds, including many components that would need to be removed, such as about 15 percent water by volume, sulfur that otherwise could end up as pollution in vehicle exhaust, and lots of char waste containing heavy metals, including iron, zinc, silver, cobalt, chromium, lanthanum, scandium, tungsten and minute amounts of gold and hafnium. Whatever the pigs eat, from dirt to nutritional supplements, ends up in the oil.

While the thick black liquid may look like its petroleum-based counterparts, the NIST study shows that looks can be deceiving. "The fact that pig manure crude oil contains a lot of water is unfavorable. They would need to get the water out," Bruno says.

The measurements were made with a new NIST test method and apparatus, the advanced distillation curve, which provides highly detailed and accurate data on the makeup and performance of complex fluids. A distillation curve charts the percentage of the total mixture that evaporates as a sample is slowly heated. Because the different components of a complex mixture typically have different boiling points, a distillation curve gives a good measure of the relative amount of each component in the mixture. NIST chemists enhanced the traditional technique by improving precision and control of temperature measurements and adding the capability to analyze the chemical composition of each boiling fraction using a variety of advanced methods.

NIST researchers analyzed the graphite-like char remaining after the distillation by bombarding it with neutrons, a non-destructive way of identifying the types and amounts of elements present. Two complementary neutron methods detected the heavy metals listed above.

Bruno and colleagues currently spend much of their time analyzing military jet fuels and are not planning a major foray into pig manure. But Bruno concedes that the effort may have a payoff. "Who knows, it might help decrease the nuisance of manure piles."

###

For more on the process of making pig waste crude, see "Converting Manure to Oil: U of I Lays Groundwork for One-of-a-Kind Pilot Plant". http://www.aces.uiuc.edu/news/stories/news3557.html

To view a video clip of Tom Bruno describing the work, please go to: http://www.nist.gov/public_affairs/techbeat/tb2008_0610.htm#crude

* L.S. Ott, B.L. Smith and T.J. Bruno. Advanced distillation curve measurement: Application to a bio-derived crude oil prepared from swine manure. Fuel (2008), doi:10.1016/j.fuel.2008.04.038.

2008-06-12T21:48:00.001-07:00

Nuclear power generation slipped 1.9% last year, though there is news that the technology is poised for growth in many countries

K.S. Parthasarathy

Nuclear Policies
Nuclear generation drops 1.9% in 2007
09 June 2008

Figures from the International Atomic Energy Agency (IAEA) show that nuclear power generation worldwide was 50 TWh lower in 2007 than in 2006, mainly due to cutbacks in three countries.

Kashiwazaki Kariwa
Kashiwazaki Kariwa is the biggest
nuclear power plant in the world.
Its extended outage has dented global
generation figures (Image: Tepco)
This 1.9% drop, from 2658 to 2608 TWh, was the first significant decline in world nuclear output in four years.

In Japan, the closure of 8000 MWe of capacity at Tokyo Electric Power Company's (Tepco's) Kashiwazaki Kariwa plant in Niigata prefecture following the earthquake on 16 July had a marked influence. The plant's closure led to Japan's nuclear electricity production dropping by almost 25 TWh to 267.3 TWh in 2007, despite no damage having been found to the reactors.

In the UK, the four oldest reactors - at Dungeness A and Sizewell A - were retired at the end of 2006 and then two larger ones - Hartlepool 2 and Heysham 1 - were laid up with boiler (steam generator) problems, leading to a drop in output of almost 12 TWh.

In Germany, there was a drop of 25 TWh due to the Brunsbuttel and Krummel nuclear power plants being shut down in June due to short circuits in the electricity grid, removing about 2000 MWe of capacity. In addition, the Biblis A and B nuclear plants, totalling 2400 MWe, remained offline due to regulatory issues for part of the year.

However, several countries reported increases in nuclear generation: Bulgaria (up 32% to 13.7 TWh); China (up 14.5% to 59.3 TWh); Russia (up 2.5% to 148.0 TWh); South Africa (up 24.7% to 12.6 TWh); and the USA (up 2.5% to 806.6 TWh) - the last amounting to 19.4 TWh.

France remained the country most reliant on nuclear energy for its electricity, producing some 420 TWh, accounting for almost 77% of its total electricity output. Lithuania followed, with 9 TWh of nuclear electricity accounting for almost 65% of its total electricity output.

According to the IAEA's Power Reactor Information System (PRIS) database, three new nuclear power reactors were connected to the grid in 2007: Kaiga 3 in India, Tianwan 2 in China and Cernavoda 2 in Romania. In addition, the Browns Ferry 1 reactor in the USA returned to service after a long-term shut down.

Also in 2007, construction of five reactors commenced: Qinshan II-4 and Hongyanhe 1 in China; Shin Kori 2 and Shin Wolsong 1 in South Korea; and the Flamanville 3 unit in France. Construction of two floating reactors was also begun in Russia. In addition, construction was also resumed in 2007 of the USA's Watts Bar 2 unit.

Theft in Trombay, Chernobyl

2008-06-12T21:34:00.000-07:00

A week ago thieves stole a swathe of telephone cables connecting Anushaktinagar, (the residential complex in which most of the scientists working in various units of the Department of Atomic Energy live) with the outside world. The Banks at the premises and schools and a few other institutions did not have phone service for a week

Almost two weeks earlier the following news appeared in the Russian paper RIA Novosti 30 May

Chernobyl chopper café plan thwarted
A gang has been arrested in Ukraine for planning to smuggle contaminated wood and scrap metal, including a helicopter, from the 18-mile exclusion zone surrounding the damaged Chernobyl nuclear power plant. In a statement, the country's security service reported that it had "identified and put a stop to the unlawful activities of a criminal gang, which had been illegally removing from Chernobyl radioactive scrap metal, automobile spare parts and timber." The statement said that the timber was usually reprocessed at covert plants and later sold as construction materials, while the metal items were usually melted down for scrap. However, the security service said the gang had also "tried to take an Mi-8 helicopter out of the exclusion zone to use it as an original coffee shop in one of Ukraine's cities." The Mi-8 helicopter was the workhorse of the Soviet armed forces and is capable of carrying up to 28 people. It was not made clear how many customers the gang had been hoping to seat.

Interesting nuclear news!!

Modified electron microscope identifies atoms

2008-02-22T00:57:00.000-08:00

A new electron microscope recently installed in Cornell's Duffield Hall enables scientists for the first time to form images that uniquely identify individual atoms in a crystal and see how those atoms bond to one another. And in living color.

K.S.Parthasarathy

Public release date: 21-Feb-2008
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Contact: Blaine Friedlander
bpf2@cornell.edu
607-254-8093
Cornell University Communications
Modified electron microscope identifies atoms

A new electron microscope recently installed in Cornell's Duffield Hall is enabling scientists for the first time to form images that uniquely identify individual atoms in a crystal and see how those atoms bond to one another. And in living color.

"The current generation of electron microscopes can be thought of as expensive black and white cameras where different atoms appear as different shades of gray," explained David Muller, Cornell associate professor of applied and engineering physics. "This microscope takes color pictures -- where each colored atom represents a uniquely identified chemical species."

The instrument is a new type of scanning transmission electron microscope (STEM), built by the NION Company of Kirkland, Wash., under an instrument-development award to Cornell from the National Science Foundation (NSF). John Silcox, the David E. Burr Professor of Engineering at Cornell, and Ondrej Krivanek of NION are co-principal investigators on the project.

The microscope incorporates new aberration-correction technology designed by Krivanek that focuses a beam of electrons on a spot smaller than a single atom -- more sharply and with greater intensity than previously possible. This allows information previously hidden in the background, or "noise," to be seen. It also provides up to a hundredfold increase in imaging speed.

The capabilities of the new instrument in analyzing a test sample are described in an article in the Feb. 22 issue of the journal Science by Muller, Silcox, Krivanek and colleagues at Cornell and in Korea and Japan.

It allows scientists to peer inside a material or a device and see how it is put together at the atomic scale where quantum effects dominate and everyday intuition fails. One of the most important applications of the new instrument will be to conduct what Silcox calls "materials pathology" to aid researchers in their development of new materials to use in electronic circuits, computer memories and other nanoscale devices. "We can look at structures people have built and tell them if they've built what they thought they did," Silcox explained.

A STEM shoots an electron beam through a thin-film sample and scans the beam across the sample in subatomic steps. In addition to forming an image, the new microscope can identify atoms in its path by a process called electron energy-loss spectrometry. Atoms in the path of the beam absorb energy from some of its electrons to kick their own electrons into higher orbits. The amount of energy this takes is different for each kind of atom.

The detector that collects electrons emerging from the sample measures the energy losses, and from this the atoms in the path of the beam can be identified. The detector can simultaneously produce multiple images -- one for every different species of atom in the sample, and these can be color-coded, each color representing a different electron energy signature.

The method also can show how atoms are bonded to one another in a crystal, because the bonding creates small shifts in the energy signatures. In earlier STEMS, many electrons from the beam, including those with changed energies, were scattered at wide angles by simple collisions with atoms. The new STEM includes magnetic lenses that collect emerging electrons over a wider angle. Previously, Silcox said, about 8 percent of the emerging electrons were collected, but the new detector collects about 80 percent, allowing more accurate readings of the small changes in energy levels that reveal bonding between atoms.

More complete collection and a brighter and a more sharply focused beam also allow the new microscope to scan much faster. In early tests it collected a 4,096-pixel image in about 30 seconds, 50 to 100 times faster than in conventional STEMs.

To demonstrate the capability of the new instrument, Muller examined a sample consisting of layers of two different materials: lanthanum-strontium-manganese oxide and strontium-titanate. This was done as part of a research project on which he is collaborating with scientists in Korea and Japan. "It's an artificial structure that will have interesting magnetic and electrical properties," he said, "but for it to work properly we have to make atomically sharp interfaces between the layers. It's really important to know if a few atoms leaked across the interface."

In the color image from the new STEM, where manganese appears red and titanium blue, a line of purple shows mixing at the edge between the two layers. "We've learned that there's room for improvement," Muller says, adding "This wasn't our best sample, but if we had put that one in it would have been a fairly boring image."

The new instrument arrived at Cornell in October, and is still undergoing calibration and testing.

The problems that limited electron imaging were identified as long ago as 1935, Silcox said, and ideas for overcoming them were outlined in 1947. But it was not until very recently that the engineering obstacles to putting them into practice were overcome. Largely, he said, this is because the problem required advanced computing, including computers to design the instrument, computer-controlled machinery to manufacture parts to fine tolerances, and computers to control the instrument itself.

###

Remarkable new clothing may someday power your iPod

2008-02-15T21:52:00.000-08:00

It is appropriate that technologists are trying to make "small" power generators for use with cell phones and IPODS. Once perfected they will have a huge market. The report published in the February issue of Nature explains an effort in that direction.

K.S.Parthasarathy

Public release date: 13-Feb-2008
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Contact: Diane Banegas
dbanegas@nsf.gov
703-292-4489
National Science Foundation
Remarkable new clothing may someday power your iPod
The promise of piezoelectric fiber pairs
A schematic illustration of a "bottle-brush " structure shows nanowires arranged around a fiber. The relative "scrubbing " of the two brushes generates electricity.
Click here for more information.

Nanotechnology researchers at the Georgia Institute of Technology are developing a shirt that harvests energy from the wearer's physical motion and converts it into electricity for powering small electronic devices worn by soldiers in the field, hikers and other users.

The research, funded by the National Science Foundation (NSF) and described in the Feb. 14 issue of Nature, details how pairs of textile fibers covered with zinc oxide nanowires generate electricity in response to applied mechanical stress. Known as "the piezoelectric effect," the resulting current flow from many fiber pairs woven into a shirt or jacket could allow the wearer's body movement to power a range of portable electronic devices. The fibers could also be woven into curtains, tents or other structures to capture energy from wind motion, sound vibration or other mechanical energy.
The Georgia Tech research team for fiber nanogenerators: (left to right) Zhong Lin Wang, Xudong Wang and Yong Qin.
Click here for more information.

"The two fibers scrub together just like two bottle brushes with their bristles touching, and the piezoelectric-semiconductor process converts the mechanical motion into electrical energy," Zhong Lin Wang, a Regents professor in the School of Materials Science and Engineering at the Georgia Institute of Technology. "Many of these devices could be put together to produce higher power output."

Wang and collaborators Xudong Wang and Yong Qin have made more than 200 of the fiber nanogenerators. Each is tested on an apparatus that uses a spring and wheel to move one fiber against the other. The fibers are rubbed together for up to 30 minutes to test their durability and power production.

The researchers have measured current of about four nanoamperes and output voltage of about four millivolts from a nanogenerator that included two fibers that were each one centimeter long. With a much improved design, Wang estimates that a square meter of fabric made from the special fibers could theoretically generate as much as 80 milliwatts of power.

So far, there is only one wrinkle in the fabric, so to speak - washing it. Zinc oxide is sensitive to moisture, so in real shirts or jackets, the nanowires would have to be protected from the effects of the washing machine.

###

The research was funded by NSF's Division of Materials Research through grant #0706436. "This multi-disciplinary research grant enables materials scientists and engineers from varied backgrounds to work together towards translating basic and applied research into viable technologies," said NSF Program Manager Harsh Deep Chopra. The research also was sponsored by the U.S. Department of Energy, and the Emory-Georgia Tech Nanotechnology Center for Personalized and Predictive Oncology.

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Iron banded worms drying out of blood could be linked to Parkinson's and Alzheimer's

2008-02-10T10:05:00.000-08:00

A very interesting paper from scientists in India and the UK
K.S.Parthasarathy

Public release date: 9-Feb-2008
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Contact: Peter Sadler
p.j.sadler@warwick.ac.uk
44-024-765-23653
University of Warwick
Iron banded worms drying out of blood could be linked to Parkinson's and Alzheimer's
Professor Sadler with diagram of iron banded fibril.
Click here for more information.

Researchers at the University of Warwick and the Indian Institute of Technology Kanpur have discovered that the mechanism that we rely on to transport iron safely through our blood stream can, in certain circumstances, collapse into a state which grows long worm-like “fibrils” banded by lines of iron rust. This process could provide the first insight into how iron gets deposited in the brain to cause some forms of Parkinson’s & Alzheimer’s and Huntington’s diseases.

Human blood relies on a protein called transferrin to safely transport iron through the bloodstream to points were it can be usefully and safely used in the body. In most other circumstances exposed iron contains many dangers for human cells. When deposited in such a state in the brain it can play a role in neurodegenerative diseases such as Parkinson’s, Huntington’s and Alzheimer’s

Transferrin takes up iron out of bloodstream and transports it by a method that combines it with carbonate to bind to two sites on the surface of the transferrin protein. It then curls around the iron and seals it in, almost like a Venus flytrap plant, to prevent it from interacting with anything else until it reaches where it is needed and can safely be used.

The research team led by Professor Peter Sadler from the University of Warwick, and Professor Sandeep Verma from the Indian Institute of Technology, found that if they took transferrin and left it to dry out on a surface, molecules of the safe transporter of iron assembled themselves into tendril - or worm-like fibrils. Even more interestingly the iron that was once safely wrapped up inside the transferrin now appeared to be settling along the length of these fibrils plating them in a series of spots or bands along the length of the tendril shape. This leaves the iron dangerously exposed and available to interact in ways that could cause cell damage.

Deposits of iron exposed in this way and found in the brain are a possible cause of some forms of Parkinson’s, Alzheimer’s and Huntington’s diseases. Until now there has been no real idea as to how iron becomes deposited there in such a dangerous way. As it is essential for the brain to have iron safely delivered to it, this observation could provide the first real clue as to how that iron comes to be deposited there in such a dangerous way. The research chemists who led this study hope that neurology researchers will be able to build on this work to gain more understanding of how these forms of Parkinson’s, Huntington’s and Alzheimer’s occur and how they can be countered.

###

The full research paper entitled Periodic Iron Nanomineralization in Human Serum Transferrin Fibrils, by Surajit Ghosh, Arindam Mukherjee, Peter J. Sadler, Sandeep Verma, has just been published in the online edition of Angewandte Chemie. The lead authors are Professor Peter Sadler from the University of Warwick, and Professor Sandeep Verma from the Indian Institute of Technology.

For further information please contact:

Professor Peter Sadler, Department of Chemistry University of Warwick Tel: +44 (0)24 7652 3653
Mobile/cell : +44 (0)7824 540980
Email: p.j.sadler@warwick.ac.uk

Professor Sandeep Verma, Department of Chemistry IIT Kanpur, Kanpur-208016 (UP), India
Tel: +91-(0512)-2597643 sverma@iitk.ac.in

Peter Dunn, Press and Media Relations Manager, Communications Office, University of Warwick,
+44 (0)24 76 523708 or mobile/cell +44 (0)7767 655860
email: p.j.dunn@warwick.ac.uk

High res Picture of Professor Sadler with diagram of Iron banded fibril available at:
http://mms.warwick.ac.uk/mms/getMedia/D509EDCC89CDF37B01ECED6D8D8020BE.jpg

PET outperforms CT in characterization of lung nodules

2008-02-07T00:50:00.000-08:00

While screening healthy volunteers, specialists found that 7 percent of 1000 persons had between one or three nodules.In patients with an untreated and undiagnosed solitary pulmonary nodules (SPN) between 7 and 30 millimeters, PET provides better identification of malignant nodules that require a more aggressive treatment approach. PET in combination with CT can also provide good identification of those nodules that are most likely to be benign, suggesting that a ‘watch and wait’ strategy can be adopted in lieu of unnecessary invasive—and expensive—procedures such as needle biopsy or surgery.

K.S.Parthasarathy

Public release date: 6-Feb-2008
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Contact: Kathryn Wiley
kwiley@snm.org
703-326-1184
Society of Nuclear Medicine
PET outperforms CT in characterization of lung nodules
Multi-institutional study comparing the diagnostic accuracy of PET and CT is featured in February Journal of Nuclear Medicine

Reston, Va.—Researchers involved in a large, multi-institutional study comparing the accuracy of positron emission tomography (PET) and computed tomography (CT) in the characterization of lung nodules found that PET was far more reliable in detecting whether or not a nodule was malignant.

“CT and PET have been widely used to characterize solitary pulmonary nodules (SPNs) as benign or malignant,” said James W. Fletcher, professor of radiology at Indiana University School of Medicine in Indianapolis, Ind. “Almost all previous studies examining the accuracy of CT for characterizing lung nodules, however, were performed more than 15 years ago with outdated technology and methods, and previous PET studies were limited by small sample sizes,” he noted.

“Detecting and characterizing SPNs is important because malignant nodules represent a potentially curable form of lung cancer. Identifying which SPNs are most likely to be malignant enables physicians to initiate the proper therapy before local or distant metastases develop,” said Fletcher.

In a head-to-head study addressing the limitations of previous studies, PET and CT images on 344 patients were independently interpreted by a panel of experts in each imaging modality, and their determination of benign and malignant nodules were compared to pathologic findings or changes in SPN size over the next two years.

The researchers found that when PET and CT results were interpreted as “probably” or “definitely” benign, the results were “strongly associated with a benign final diagnosis”—in other words, the modalities were equally good at making this determination. PET’s superior specificity (accuracy in characterizing a nodule as benign or malignant), however, resulted in correctly classifying 58 percent of the benign nodules that had been incorrectly classified as malignant on CT. Furthermore, when PET interpreted SPNs as definitely malignant, a malignant final diagnosis was 10 times more likely than a benign.

SPNs are commonly encountered in both primary and specialty settings, often showing up on chest X-rays obtained for some other purpose than cancer screening and are often the first manifestation of lung cancer. The question for these patients then becomes whether to undergo surgery, undergo a needle biopsy or “watch and wait” to find out if the nodule is benign or malignant but treatable.

“In patients with an untreated and undiagnosed SPN between 7 and 30 millimeters, PET provides better identification of malignant nodules that require a more aggressive treatment approach,” said Fletcher. “PET in combination with CT can also provide good identification of those nodules that are most likely to be benign, suggesting that a ‘watch and wait’ strategy can be adopted in lieu of unnecessary invasive—and expensive—procedures such as needle biopsy or surgery,” he added.

According to the American Cancer Society, lung cancer is the leading cause of cancer deaths in both men and women in the United States, with approximately 155,000 deaths each year. Although the survival rate is 49 percent for cases detected when the disease is still localized, only 16 percent of lung cancer cases are diagnosed at this early stage. Recently, almost 7 percent of 1,000 healthy volunteers in New York who participated in the Early Lung Cancer Action Project were found to have between one and three nodules on baseline screening X-rays.

###

Co-authors of “A Comparison of the Diagnostic Accuracy of F18-FDG PET and CT in the Characterization of Solitary Pulmonary Nodules” include Fletcher; Steven M. Kymes, department of ophthalmology and visual sciences, Washington University School of Medicine, St. Louis, Mo.; Michael Gould, department of Veterans Affairs, Palo Alto Health Care System and department of medicine; George Segall, department of Veterans Affairs, Palo Alto Health Care System and department of radiology, Stanford School of Medicine, Stanford, Calif.; Naomi Alazraki, department of radiology, Emory University School of Medicine, Atlanta, Ga.; R. Edward Coleman, department of radiology, Duke University School of Medicine, Durham, N.C.; Val. J. Lowe, department of radiology, Mayo Clinic, Rochester, Minn.; Charles Marn, department of radiology and Lyn A. Thet, department of medicine, University of Wisconsin School of Medicine, Madison, Wis.; Kelvin Lee, department of Veterans Affairs, Cooperative Studies Program Coordinating Center, Palo Alto, Calif.

Credentialed media: To obtain a copy of this article—and online access to the Journal of Nuclear Medicine— please contact Kathryn Wiley by phone at (703) 326-1184 or send an e-mail to kwiley@snm.org. Current and past issues of the Journal of Nuclear Medicine can be found online at http://jnm.snmjournals.org. Print copies can be obtained by contacting the SNM Service Center, 1850 Samuel Morse Drive, Reston, VA 20190-5316; phone (800) 513-6853; e-mail servicecenter@snm.org; fax (703) 708-9015. A subscription to the journal is an SNM member benefit.

About SNM—Advancing Molecular Imaging and Therapy

SNM is an international scientific and professional organization of more than 16,000 members dedicated to promoting the science, technology and practical applications of molecular and nuclear imaging to diagnose, manage and treat diseases in women, men and children. Founded more than 50 years ago, SNM continues to provide essential resources for health care practitioners and patients; publish the most prominent peer-reviewed journal in the field (Journal of Nuclear Medicine); host the premier annual meeting for medical imaging; sponsor research grants, fellowships and awards; and train physicians, technologists, scientists, physicists, chemists and radiopharmacists in state-of-the-art imaging procedures and advances. SNM members have introduced—and continue to explore—biological and technological innovations in medicine that noninvasively investigate the molecular basis of diseases, benefiting countless generations of patients. SNM is based in Reston, Va.; additional information can be found online at http://www.snm.org.

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The world's best microscope

2008-01-23T01:15:00.000-08:00

The US Department of Enegry's collaborative team has installed the world's most powerful transmission electron microscope -- capable of producing images with half-angstrom resolution (half a ten-billionth of a meter), less than the diameter of a single hydrogen atom -- at the Department of Energy's National Center for Electron Microscopy (NCEM) at Lawrence Berkeley National Laboratory.

Out side users can use it from October 2008

K.S.Parthasarathy

Public release date: 22-Jan-2008
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Contact: Paul Preuss
paul_preuss@lbl.gov
510-486-6249
DOE/Lawrence Berkeley National Laboratory
Debut of TEAM 0.5, the world's best microscope
TEAM 0.5, the world's best transmission electron microscope, has been installed at the National Center for Electron Microscopy.
Click here for more information.

BERKELEY, CA -- TEAM 0.5, the world's most powerful transmission electron microscope -- capable of producing images with half-angstrom resolution (half a ten-billionth of a meter), less than the diameter of a single hydrogen atom -- has been installed at the Department of Energy's National Center for Electron Microscopy (NCEM) at Lawrence Berkeley National Laboratory.

"We have beam down the column," announced Uli Dahmen of Berkeley Lab's Materials Sciences Division, who is head of NCEM and director of DOE's collaborative TEAM Project, when the TEAM 0.5 microscope first delivered its ultrabright electron beam at Berkeley Lab in late December.

The TEAM Project (TEAM stands for Transmission Electron Aberration-corrected Microscope) is led by Berkeley Lab in a collaboration with DOE's Argonne and Oak Ridge National Laboratories, the Frederick Seitz Materials Laboratory of the University of Illinois, and two private companies specializing in electron microscopy, the FEI Company headquartered in Portland, Oregon, and CEOS of Heidelberg, Germany.

Now that TEAM 0.5's basic systems are operational, additional components and facilities are being completed and tuned, including a state-of-the-art control room display that shows the sample under the microscope on a flat panel resembling a wide-screen, high-definition TV. After a long series of rigorous tests and adjustments, TEAM 0.5 will become available to outside users by October, 2008.
Where these two gold crystals meet they are joined by a complex arrangement of atoms, forming a nanobridge that accommodates their different orientations. The atoms are 2.3 angstroms apart. TEAM

Where these two gold crystals meet they are joined by a complex arrangement of atoms, forming a nanobridge that accommodates their different orientations. The atoms are 2.3 angstroms apart. TEAM...

Atom by atom in 3-D

In preliminary tests at the FEI Company, before the TEAM 0.5 was shipped, NCEM's Christian Kisielowski tested the microscope's ability to resolve individual atoms and precisely locate their positions in three dimensions. He made a series of images of two gold crystals connected by a "nanobridge" only a few dozen atoms wide. From each exposure to the next, individual gold atoms could be seen changing positions.

To achieve this extraordinary resolution, TEAM 0.5 embodies technical advances that have only recently become possible, including ultra-stable electronics, improved aberration correctors, and an extremely bright electron source.

Spherical aberration degrades images, making points of light look like disks, and correcting it can make dramatic improvements to image resolution. (This was famously demonstrated in 1993, when spherical aberration in the Hubble Space Telescope's optical lenses was corrected in a special space mission.) In the case of electron microscopes, a series of multipole magnetic lenses of varying geometries shapes the electron beam.

"Correcting spherical aberration in an electron microscope has long been possible in theory," says Dahmen. "But only recently has it become practical," because today's stable electronics reduce drift and fast computers allow continuous adjustments in real time. Corrector technology has even become available commercially, says Dahmen, "but no off-the-shelf corrector can match TEAM 0.5's ability to compensate even higher-order aberrations."

Correcting spherical aberration makes it possible to use the TEAM 0.5 not only for broad-beam, "wide-angle" images but also for scanning transmission electron microscopy (STEM), in which the tightly focused electron beam is moved across the sample as a probe, capable of performing spectroscopy on one atom at a time -- an ideal way to precisely locate impurities in an otherwise homogeneous sample, such as individual dopant atoms in a semiconductor material.

Aberration correction is also essential for another advanced feature of TEAM 0.5: its ability to maintain high resolution with lower electron beam energies.

"Low-energy electrons have longer wavelengths, so they are harder to focus," Dahmen explains. "Aberration correction allows better than one-angstrom resolution with excellent contrast even at 80 kilovolts. This is important when you don't want to damage the sample with a high-energy beam -- in biological studies, for example."

It's not just high resolution that makes TEAM 0.5 the world's best microscope, Dahmen says. When all the electrons in the beam focus at the same plane, image contrast and signal-to-noise ratio improve tremendously.

"It's because the signal-to-noise ratio is so good that you can adjust focus atom by atom, with enough sensitivity to obtain information about the three-dimensional atomic structure of a single nanoparticle." Dahmen adds, "This brings us within reach of meeting the great challenge posed by the famous physicist Richard Feynman in 1959: the ability to analyze any chemical substance simply by looking to see where the atoms are."

The position of individual atoms in a structure can be determined by taking images at different angles, from which the computer reconstructs a 3-D tomograph of the sample, as in a CAT scan. To make this possible an innovative system capable of tilting and rotating the sample, and moving it up, down, or sideways under the electron beam, is also being developed at NCEM.

Much smaller than sample stages now in use, the new TEAM stage will be housed entirely inside the microscope column. Manipulating the sample by such methods as minute piezoelectric "crawlers" that change shape when electricity is applied, the new stage will be able to control and reproduce the sample's position and attitude with an accuracy of less than a billionth of a meter.

Installation of the new stage must await the next phase of the TEAM Project: the TEAM I microscope, due to be set up at NCEM early in 2009.

While TEAM 0.5 corrects spherical aberration in both the "probe" beam (the electron beam before it strikes the sample) and the image beam (after it exits the sample, but before it reaches the detector), TEAM I will also correct chromatic aberration in the image beam, which has never beeen accomplished before. Spherical aberration is caused by the shape of a lens; chromatic aberration results when a lens refracts light or electrons of different wavelengths (different colors or energies) at different angles.

"Correcting chromatic aberration is harder and takes more space," says Dahmen. "The chromatic aberration corrector will add two feet to the height of the TEAM I column. But the new configuration will also allow us to enlarge the gap between the pole pieces, into which the sample fits. In TEAM 0.5 this gap is only about two millimeters, so we have to use traditional outside-mounted sample stages, with limited space to manipulate the sample. In TEAM I the gap will be five millimeters; the sample stage will have much greater freedom of movement."

New vistas in the realm of the small

TEAM 0.5 and TEAM I will be housed side by side at NCEM for some time, occupying the two multistory "silos" that until recently were the homes of the historic High-Voltage Electron Microscope and the Atomic Resolution Microscope, the most powerful microscopes in the world when NCEM was established in the early 1980s.

Ambitious as those microscopes were in their day, says TEAM's Project Manager, Peter Denes of the Engineering Division, "when the TEAM Project was launched in 2004, it was not quite clear if the goals could even be achieved. The electron microscopy community had never done a collaborative project like TEAM before, and certainly not with full DOE project-management rigor."

Says Denes, "Perhaps the biggest contributor to success was a series of scientific workshops that contributed to forming a converging opinion on what the next steps would be, and what would constitute success. That helped in getting everyone -- if not quite on the same page -- at least in the same book."

Dahmen agrees. "This is a big jump for the microscopy community. TEAM's success will open the door to other ambitious developments around the world."

Dahmen suggests at least two broad categories of researchers who will benefit from the powerful new electron microscopes: experts with sophisticated microscopy problems to solve, and scientists less familiar with electron microscopy but with a particular problem for which microscopy can provide the answer.

"For example, Jim Zuo at the University of Illinois is doing studies of electron diffraction from the surface of single nanoparticles," Dahmen says. "He sees evidence of surface contraction. But when we at NCEM do imaging of similar nanoparticles, we find that the surface is expanding. Jim looks forward to using the TEAM microscope because it can do diffraction and imaging of the same particle at the same time -- a grand experiment, and the only way to solve the apparent contradiction."

An example of a problem-solving nonspecialist, says Dahmen, might be a materials scientist who has created a new kind of nanostructure, such as a tetrapod semiconductor, and needs to know exactly where in this complex, three-dimensional shape the impurity atoms reside. "TEAM's ability to image the structure in 3-D through tomography and its ability to do spectroscopy with single-atom sensitivity can identify each kind of atom at each position in the structure. That has never been possible before."

The basic TEAM components of aberration correction, enhanced signal-to-noise ratio, single-atom sensitivity, and an ultrabright beam that can be used in both TEM and STEM modes -- all the while manipulating the sample in the beam -- are goals that until recently seemed at the very edge of technological daring. All are on track, and some have been solved ahead of schedule. The TEAM Project's continuing success, signaled by the installation of TEAM 0.5 at NCEM, has opened the possibility of numerous future advances in electron microscopy that were barely conceivable when TEAM was launched.

The multi-institutional TEAM project represents a new kind of distributed planning and cooperation for the electron microscope community, moving beyond the limited, incremental improvements of individual investigators and harnessing the power of collaboration. Argonne National Laboratory is leading the development of the chromatic-aberration corrector in close collaboration with CEOS in Heidelberg. The University of Illinois's Frederick Seitz Materials Laboratory is jointly developing the new piezoelectric-controlled sample stage with Berkeley Lab's NCEM, and Oak Ridge National Laboratory is helping to optimize the new probe corrector. NCEM acts as project leader to integrate the individual components into single instruments, in close collaboration with all other TEAM partners. The TEAM Project is sponsored by the U.S. Department of Energy's Office of Science. For more about the TEAM Project, visit http://ncem.lbl.gov/TEAM-project/.

###

Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California. Visit our website at http://www.lbl.gov.

New methane storage technology exceeds DOE goals

2008-01-22T01:18:00.000-08:00

The new methane storage technology appears to be a breakthrough. The cost implications of the technology are not known at least until now!

K.S.Parthasarathy

New methane storage technology exceeds DOE goals
Journal of the American Chemical Society

In a major advance in alternative fuel technology, researchers report development of a sponge-like material with the highest methane storage capacity ever measured. It can hold almost one-third more methane than the U.S. Department of Energy’s (DOE) target level for methane-powered cars, they report in a new study. It is scheduled for the Jan. 23 issue of ACS’ Journal of the American Chemical Society, a weekly publication.

Hong-Cai Zhou and colleagues note that lack of an effective, economical and safe on-board storage system for methane gas has been one of the major hurdles preventing methane-driven automobiles from competing with traditional ones. Recently, highly-porous, crystalline materials called metal-organic frameworks (MOFs) have emerged as promising storage materials due to their high surface areas. However, none of the MOF compounds have reached DOE target levels considered practical for fuel storage applications, the scientists say.

The report describes development of a new type of MOF, called PCN-14, that has a high surface area of over 2000 m2/g. Laboratory studies show that the compound, composed of clusters of nano-sized cages, has a methane storage capacity 28 percent higher than the DOE target, a record high for methane-storage materials, the researchers say. — MTS

ARTICLE #2 FOR IMMEDIATE RELEASE “Metal-Organic Framework from an Anthracene Derivative Containing Nanoscopic Cages Exhibiting High Methane Uptake”

DOWNLOAD PDF http://pubs.acs.org/cgi-bin/sample.cgi/jacsat/asap/pdf/ja0771639.pdf
DOWNLOAD HTML http://pubs.acs.org/cgi-bin/sample.cgi/jacsat/asap/html/ja0771639.html

CONTACT:
Hong-Cai Zhou, Ph.D.
Miami University
Oxford, Ohio 45056
Phone: 513-529-8091
Email: zhouh@muohio.edu

Indian medicinal plant Acanthus ilicifolius may combat liver cancer

2008-01-17T01:29:00.000-08:00

Public release date: 16-Jan-2008
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Contact: Jing Zhu
wjg@wjgnet.com
0086-105-908-0039
World Journal of Gastroenterology
Indian medicinal plant Acanthus ilicifolius may combat liver cancer

Liver cancer is the fifth most common cancer in the world with a poor prognosis. About three quarters of the cases of liver cancer are found in Southeast Asia, including China, Hong Kong, Taiwan, Korea, India, and Japan. The frequency of liver cancer in Southeast Asia and sub-Saharan Africa is greater than 20 cases per 100,000 population. Moreover, recent data show the frequency of liver cancer in the U.S. overall is rising.

With the increasing trend in the incidence of cancers in our country, biomedical research directed at early detection and diagnosis, prognosis and survival, as well as prevention of progression of malignancy, is of prime importance. The aim of cancer chemoprevention is to circumvent the development and progression of malignant cells through the use of non-cytotoxic nutrients, herbal preparations/natural plant products, and/or pharmacological agents. Encouraging dietary intake with herbal supplements may therefore be an effective strategy to limit DNA lesions and organic injuries leading to cancers and other chronic degenerative diseases. A research article published in the December 28 issue of the World Journal of Gastroenterology explores this point.

A research article published on December 28, 2007 in the World Journal of Gastroenterology (volume 13, issue 48) addresses this problem. The research team led by Prof. Malay Chatterjee from Jadavpur University investigated the primary chemopreventive mechanisms of Acanthus ilicifolius in an in vivo tumor-transplanted murine model. A. ilicifolius, popularly known as ¡°Harkach Kanta¡± is distributed widely throughout the mangroves of India, including Sunderbans in West Bengal, west coasts, and the Andamans, and in other Asian countries like Singhal, Burma, China, Thailand etc.

The results showed the aqueous leaf extract (ALE) of the plant was substantially effective in preventing hepatic DNA alterations and sister-chromatid exchanges (a type of chromosomal damage) in tumor-bearing mice. The study further demonstrated that ALE treatment was able to limit liver metallothionein expression, a potential marker for cell proliferation, and lengthen the mean survival of animals to a significant extent. The findings suggest that A. ilicifolius may be used as a potential chemoprotector against hepatic neoplasia.

This research from Prof. Chatterjee¡¯s laboratory opens up a promising avenue in cancer chemoprevention with the use of indigenous plants. The results obtained from this in vivo study seem interesting and encouraging. Lack of toxicity favors further preclinical evaluation of A. ilicifolius in a defined chemical carcinogenesis model. Elucidation of its anticarcinogenic mechanisms of action at the intricate molecular circuits, and isolation and characterization of its active principles, will provide a better understanding of the anti-cancer/chemoprevention strategy of A. ilicifolius. If these studies are found to be really functional, we will have the beginning of a new chemoprevention program with herbal supplements that could have the broadest implications for the well-being of society.

###

6.1 Reference: Chakraborty T, Bhuniya D, Chatterjee M, Rahaman M, Singha D, Chatterjee BN, Datta S, Rana A, Samanta K, Srivastawa S, Maitra SK, Chatterjee M. Acanthus ilicifolius plant extract prevents DNA alterations in a transplantable Ehrlich ascites carcinoma-bearing murine model. World J Gastroenterol 2007; 13(48): 6538-6548
http://www.wjgnet.com/1007-9327/13/6538.asp

6.2 Correspondence to: Professor Malay Chatterjee, Ph.D. D.Sc., Chemical Carcinogenesis and Chemoprevention Laboratory, Division of Biochemistry, Department of Pharmaceutical Technology, Jadavpur University, P.O. Box-17028, Calcutta 700032, India. mcbiochem@yahoo.com
Telephone: +91-33-24146393 Fax: +91-33-24146393

6.3 About World Journal of Gastroenterology

World Journal of Gastroenterology (WJG), a leading international journal in gastroenterology and hepatology, has established a reputation for publishing first class research on esophageal cancer, gastric cancer, liver cancer, viral hepatitis, colorectal cancer, and H pylori infection and provides a forum for both clinicians and scientists. WJG has been indexed and abstracted in Current Contents/Clinical Medicine, Science Citation Index Expanded (also known as SciSearch) and Journal Citation Reports/Science Edition, Index Medicus, MEDLINE and PubMed, Chemical Abstracts, EMBASE/Excerpta Medica, Abstracts Journals, Nature Clinical Practice Gastroenterology and Hepatology, CAB Abstracts and Global Health. ISI JCR 2003-2000 IF: 3.318, 2.532, 1.445 and 0.993. WJG is a weekly journal published by WJG Press. The publication dates are the 7th, 14th, 21st, and 28th day of every month. The WJG is supported by The National Natural Science Foundation of China, No. 30224801 and No. 30424812, and was founded with the name of China National Journal of New Gastroenterology on October 1, 1995, and renamed WJG on January 25, 1998.

6.4 About The WJG Press

The WJG Press mainly publishes World Journal of Gastroenterology.

Clemson researcher studies carbon fibers for nuclear reactor safety

2007-12-11T01:13:00.000-08:00

Carbon nano fibres may be very useful in Gen IV nuclear power reactors.The US department of Energy(DOE) is extending support to a professor to carry out research on these fibres.

K.S.Parthasarathy

Public release date: 10-Dec-2007

Contact: Amod Ogale
ogale@clemson.edu
864-656-5483
Clemson University
Clemson researcher studies carbon fibers for nuclear reactor safety

CLEMSON, S.C. –– Carbon fibers that are only one-tenth the size of a human hair, but three times stronger than steel, may hold up to the intense heat and radiation of next generation nuclear power generators, providing a safety mechanism. The “Gen IV” power-generating reactors are being designed to provide low-cost electricity, but with a built-in safety mechanism current reactors do not have.

The Department of Energy (DoE) has awarded chemical engineering professor Amod Ogale, deputy director of the Center for Advanced Engineering Fibers and Films (CAEFF), a $450,000 grant to research carbon fibers embedded into a carbon matrix that do not melt in extreme temperatures for potential use in Gen IV power generators. Presently, about 20 percent of electricity produced in the United States is from nuclear sources.

“One proposed design of the next generation of nuclear plants will consist of a helium-cooled generator that will operate in the range of 1,200 to 1,800 degrees Fahrenheit,” says Ogale. “A critical safety requirement for this reactor is that it can shut down safely in the event of a malfunction where coolant flow is interrupted. Steel alloys currently used internally in reactors melt at the peak temperature of 2500 degrees Fahrenheit, where carbon fiber composites do not.”

Carbon fiber composites are already used successfully in jetliner brake systems because of their ability to withstand high temperatures without melting. However, their performance in a nuclear environment is not adequately understood.

Ogale and his team will study the neutron-radiation damage effects on carbon fibers.

His prior research has shown that including carbon nanotubes (large molecules of carbon that are tube-shaped and 30 nanometers in size) in carbon fibers leads to the development of a more uniform texture that improves the properties of the ultra-thin carbon fibers.

In his research, Ogale expects to generate high graphitic crystallinity, a solid ordered pattern which is evenly distributed so that any changes in fiber properties due to radiation can be minimized.

Irradiation experiments will be conducted in collaboration with researchers at Oak Ridge National Labs. South Carolina State University researchers also will participate in the study.

“This research will lead to a fundamental understanding of how the nanotubes set themselves up to provide radiation-damage tolerance to carbon fibers,” said Ogale.

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Editors: This material is based upon work supported by DoE under grant number DE-FG02-07ER46364. Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of DoE.

Secondhand smoke damages lungs, MRIs show

2007-11-27T01:01:00.000-08:00

Researchers use MRI scanner to image damage in the lung due to second-hand smoke.They presented this work at RSNA 2007

K.S.Parthasarathy

Public release date: 26-Nov-2007

Contact: Rachel Salis-Silverman
Salis@email.chop.edu
267-426-6063
Children's Hospital of Philadelphia
Secondhand smoke damages lungs, MRIs show
The apparent diffusion coefficient (ADC) measures lung injury, indicated by different colors.
Click here for more information.

It’s not a smoking gun, but it’s smoking-related, and it’s there in bright medical images: evidence of microscopic structural damage deep in the lungs, caused by secondhand cigarette smoke. For the first time, researchers have identified lung injury to nonsmokers that was long suspected, but not previously detectable with medical imaging tools.

The researchers suggest that their findings may strengthen public health efforts to restrict secondhand smoke.

“We used a special type of magnetic resonance imaging to find these structural changes in the lungs,” said study leader Chengbo Wang, Ph.D., a magnetic resonance physicist in the Department of Radiology at The Children’s Hospital of Philadelphia. “Almost one-third of nonsmokers who had been exposed to secondhand cigarette smoke for a long time developed these structural changes.” Formerly at the University of Virginia, Wang collaborated with radiology researchers at that institution, where they acquired the MRIs from adult smokers and nonsmokers.

Wang presented the team’s findings in Chicago at the annual meeting of the Radiological Society of North America. Although the participants in the research study were adults, Wang said the results have implications for the 35 percent of American children who live in homes where regular smoking occurs.

The researchers studied 60 adults between ages 41 and 79, 45 of whom had never smoked. The 45 non-smokers were divided into groups with low and high exposure to secondhand smoke; the high-exposure subjects had lived with a smoker for at least 10 years, often during childhood. The 15 current or former smokers formed a positive control group.

The research team prepared an isotope of helium called helium-3 by polarizing it to make it more visible in the MRI. Researchers diluted the helium in nitrogen and had research subjects inhale the mixture. Unlike ordinary MRIs, this MRI machine measured diffusion, the movement of helium atoms, over 1.5 seconds. The helium atoms moved a greater distance than in the lungs of normal subjects, indicating the presence of holes and expanded spaces within the alveoli, tiny sacs within the lungs.

The researchers found that almost one-third of the non-smokers with high exposure to secondhand smoke had structural changes in their lungs similar to those found in the smokers. “We interpreted those changes as early signs of lung damage, representing very mild forms of emphysema,” said Wang. Emphysema, a lung disease that is a major cause of death in the U.S., is commonly found in heavy smokers.

The researchers also found a seemingly paradoxical result among two-thirds of the high-exposure group of non-smokers—diffusion measurements that were lower than those found in the low-exposure group. Although these findings require more study, said Wang, they may reflect a narrowing in airways caused by early stages of another lung disease, chronic bronchitis.

“To our knowledge, this is the first imaging study to find lung damage in non-smokers heavily exposed to secondhand smoke,” said Wang. “We hope our work strengthens the efforts of legislators and policymakers to limit public exposure to secondhand smoke.”

###

The study received financial support from the National Heart, Lung and Blood Institute, the Flight Attendant Medical Research Institute, the Commonwealth of Virginia Technology Research Fund, and Siemens Medical Solutions.

Wang’s co-authors were Talissa A. Altes, M.D., and Kai Ruppert, Ph.D., now of the Children’s Hospital Radiology Department; and G. Wilson Miller, Ph.D., Eduard E. deLange, M.D., Jaime F. Mata, Ph.D., Gordon D. Cates, Jr., Ph.D., and John P. Mugler III, Ph.D., all of the University of Virginia Department of Radiology. Drs. Wang, Altes, and Ruppert were previously at the University of Virginia as well.

About The Children's Hospital of Philadelphia: The Children's Hospital of Philadelphia was founded in 1855 as the nation's first pediatric hospital. Through its long-standing commitment to providing exceptional patient care, training new generations of pediatric healthcare professionals and pioneering major research initiatives, Children's Hospital has fostered many discoveries that have benefited children worldwide. Its pediatric research program is among the largest in the country, ranking third in National Institutes of Health funding. In addition, its unique family-centered care and public service programs have brought the 430-bed hospital recognition as a leading advocate for children and adolescents. For more information, visit http://www.chop.edu.

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Post-treatment PET scans can reassure cervical cancer patients

2007-11-21T08:31:00.000-08:00

PET scanner is a very powerful tool which can pinpoint secondary cancers , if any, in patients who underwent radiation treatment

K.S.Parthasarathy

Public release date: 20-Nov-2007

Contact: Gwen Ericson
ericsong@wustl.edu
314-286-0141
Washington University in St. Louis
Post-treatment PET scans can reassure cervical cancer patients

St. Louis, Nov. 20, 2007 — Whole-body PET (positron emission tomography) scans done three months after completion of cervical cancer therapy can ensure that patients are disease-free or warn that further interventions are needed, according to a study at Washington University School of Medicine in St. Louis.

"This is the first time we can say that we have a reliable test to follow cervical cancer patients after therapy," says Julie K. Schwarz, M.D., Ph.D., a Barnes-Jewish Hospital resident in the Department of Radiation Oncology. "We ask them to come back for a follow-up visit about three months after treatment is finished, and we perform a PET scan. If the scan shows a complete response to treatment, we can say with confidence that they are going to do extremely well. That's really powerful."

Schwarz and colleagues published their study in the Nov. 21, 2007 issue of the Journal of the American Medical Association (JAMA).

Without a test like PET, it can be difficult to tell whether treatment has eliminated cervical tumors, Schwarz says. That's because small tumors are hard to detect with pelvic exams, and overt symptoms, such as leg swelling, don't occur until tumors grow quite large. Furthermore, CT and MRI scans often don't differentiate tumor tissue from surrounding tissues, Pap tests can be inaccurate because of tissue changes induced by radiation therapy, and no blood test exists to detect the presence of cervical cancer.

Cancerous tumors glow brightly in the PET scans used in the study, called FDG-PET scans, which detect emissions from radioactively tagged blood sugar, or glucose. Tumor tissue traps more of the glucose than does normal tissue, making tumors readily discernable.

Not only can post-treatment PET scans reassure those patients whose tumors respond well to therapy, they can also identify those patients whose tumors have not responded so that their physicians can explore other treatment options before the cancer advances further. These options can include surgery to remove tissue, standard chemotherapy or experimental therapies available through clinical trials.

"Follow-up PET scans can also be very useful tools for physicians conducting clinical trials of new therapies," Schwarz says. "Our study has shown that the scans are predictive of long-term survival. Using PET scans, clinical researchers can get an early readout of how effective experimental treatments might be."

Schwarz and colleagues also have a project to compare follow-up PET results with tumor biology to find out why some tumors don't respond well to therapy. In a study that won her a Resident Clinical Basic Science Research Award from the American Society for Therapeutic Radiation and Oncology, a global organization of medical professionals, Schwarz found differences in gene activity between tumors from patients that responded well and those that had persistent disease. Ongoing research will look for the significance of these differences.

The study's senior author, Perry Grigsby, M.D., professor of radiation oncology, of nuclear medicine and of obstetrics and gynecology and a radiation oncologist with the Siteman Cancer Center at Washington University School of Medicine and Barnes-Jewish Hospital, has overseen a patient database that now has PET images and tumor samples from hundreds of cervical cancer patients.

"We have a tremendous database of PET images collected from patients in the department since 1998," Schwarz says. "We want to combine these results with analyses of tumor biopsies so that we can more effectively choose additional therapies for patients who haven't responded to the initial treatment."

###

Schwarz JK, Siegel BA, Dehdashti F, Grigsby PW. Association of posttherapy positron emission tomography with tumor response and survival in cervical carcinoma. Journal of the American Medical Association, November 21, 2007.

Funding from the Department of Radiology and the Department of Radiation Oncology at Washington University School of Medicine in St. Louis supported this research.

Washington University School of Medicine's 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.

Siteman Cancer Center is the only federally-designated Comprehensive Cancer Center within a 240-mile radius of St. Louis. Siteman Cancer Center is composed of the combined cancer research and treatment programs of Barnes-Jewish Hospital and Washington University School of Medicine. Siteman has satellite locations in West County and St. Peters, in addition to its full-service facility at Washington University Medical Center on South Kingshighway.

Remote-control nanoparticles deliver drugs directly into tumors

2007-11-17T08:23:00.000-08:00

Public release date: 16-Nov-2007

Contact: Elizabeth Thomson
thomson@mit.edu
617-258-5402
Massachusetts Institute of Technology
MIT: Remote-control nanoparticles deliver drugs directly into tumors

CAMBRIDGE, MA--MIT scientists have devised remotely controlled nanoparticles that, when pulsed with an electromagnetic field, release drugs to attack tumors. The innovation, reported in the Nov. 15 online issue of Advanced Materials, could lead to the improved diagnosis and targeted treatment of cancer.

In earlier work the team, led by Sangeeta Bhatia, M.D.,Ph.D., an associate professor in the Harvard-MIT Division of Health Sciences & Technology (HST) and in MIT's Department of Electrical Engineering and Computer Science, developed injectable multi-functional nanoparticles designed to flow through the bloodstream, home to tumors and clump together. Clumped particles help clinicians visualize tumors through magnetic resonance imaging (MRI).

With the ability to see the clumped particles, Bhatia’s co-author in the current work, Geoff von Maltzahn, asked the next question: “Can we talk back to them?”

The answer is yes, the team found. The system that makes it possible consists of tiny particles (billionths of a meter in size) that are superparamagnetic, a property that causes them to give off heat when they are exposed to a magnetic field. Tethered to these particles are active molecules, such as therapeutic drugs.

Exposing the particles to a low-frequency electromagnetic field causes the particles to radiate heat that, in turn, melts the tethers and releases the drugs. The waves in this magnetic field have frequencies between 350 and 400 kilohertz—the same range as radio waves. These waves pass harmlessly through the body and heat only the nanoparticles. For comparison, microwaves, which will cook tissue, have frequencies measured in gigahertz, or about a million times more powerful.

The tethers in the system consist of strands of DNA, “a classical heat sensitive material,” said von Maltzahn, a graduate student in HST. Two strands of DNA link together through hydrogen bonds that break when heated. In the presence of the magnetic field, heat generated by the nanoparticles breaks these, leaving one strand attached to the particle and allowing the other to float away with its cargo.

One advantage of a DNA tether is that its melting point is tunable. Longer strands and differently coded strands require different amounts of heat to break. This heat-sensitive tuneability makes it possible for a single particle to simultaneously carry many different types of cargo, each of which can be released at different times or in various combinations by applying different frequencies or durations of electromagnetic pulses.

To test the particles, the researchers implanted mice with a tumor-like gel saturated with nanoparticles. They placed the implanted mouse into the well of a cup-shaped electrical coil and activated the magnetic pulse. The results confirm that without the pulse, the tethers remain unbroken. With the pulse, the tethers break and release the drugs into the surrounding tissue.

The experiment is a proof of principal demonstrating a safe and effective means of tunable remote activation. However, work remains to be done before such therapies become viable in the clinic.

To heat the region, for example, a critical mass of injected particles must clump together inside the tumor. The team is still working to make intravenously injected particles clump effectively enough to achieve this critical mass.

“Our overall goal is to create multifunctional nanoparticles that home to a tumor, accumulate, and provide customizable remotely activated drug delivery right at the site of the disease,” said Bhatia.

###

Co-authors on the paper are Austin M. Derfus, a graduate student at the University of California at San Diego; Todd Harris, an HST graduate student; Erkki Ruoslahti and Tasmia Duza of The Burnham Institute in La Jolla, CA; and Kenneth S. Vecchio of the University of San Diego.

The research was supported by grants from the David and Lucile Packard Foundation, the National Cancer Institute of the National Institutes of Health. Dervis was supported by a G.R.E.A.T fellowship from the University of California Biotechnology Research and Educational Program.

Written by Elizabeth Dougherty, Harvard-MIT Division of Health Sciences and Technology

Scientists discover record-breaking hydrogen storage materials for use in fuel cells

2007-11-13T08:27:00.000-08:00

UVa researchers found materials that absorb hydrogen up to 14 percent by weight at room temperature. By absorbing twice as much hydrogen, the new materials could help make the dream of a hydrogen economy come true.

K.S.Parthasarathy

Public release date: 12-Nov-2007
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Contact: Bellave Shivaram
bss2d@virginia.edu
434-806-9582
University of Virginia
Scientists discover record-breaking hydrogen storage materials for use in fuel cells

Scientists at the University of Virginia have discovered a new class of hydrogen storage materials that could make the storage and transportation of energy much more efficient — and affordable — through higher-performing hydrogen fuel cells.

Bellave S. Shivaram and Adam B. Phillips, the U.Va. physicists who invented the new materials, will present their finding at 8 p.m., Monday, Nov. 12, at the International Symposium on Materials Issues in a Hydrogen Economy at the Omni Hotel in Richmond, Va.

“In terms of hydrogen absorption, these materials could prove a world record,” Phillips said. “Most materials today absorb only 7 to 8 percent of hydrogen by weight, and only at cryogenic [extremely low] temperatures. Our materials absorb hydrogen up to 14 percent by weight at room temperature. By absorbing twice as much hydrogen, the new materials could help make the dream of a hydrogen economy come true.”

In the quest for alternative fuels, U.Va.’s new materials potentially could provide a highly affordable solution to energy storage and transportation problems with a wide variety of applications. They absorb a much higher percentage of hydrogen than predecessor materials while exhibiting faster kinetics at room temperature and much lower pressures, and are inexpensive and simple to produce.

“These materials are the next generation in hydrogen fuel storage materials, unlike any others we have seen before,” Shivaram said. “They have passed every litmus test that we have performed, and we believe they have the potential to have a large impact.”

The inventors believe the novel materials will translate to the marketplace and are working with the U.Va. Patent Foundation to patent their discovery.

“The U.Va. Patent Foundation is very excited to be working with a material that one day may be used by millions in everyday life,” said Chris Harris, senior licensing manager for the U.Va. Patent Foundation. “Dr. Phillips and Dr. Shivaram have made an incredible breakthrough in the area of hydrogen absorption.”

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Phillips’s and Shivaram’s research was supported by the National Science Foundation and the U.S. Department of Energy.

World's smallest radio uses single nanotube to pick up good vibrations

2007-11-01T10:33:00.000-07:00

Public release date: 31-Oct-2007
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Contact: Robert Sanders
rsanders@berkeley.edu
510-643-6998
University of California - Berkeley
World's smallest radio uses single nanotube to pick up good vibrations

Berkeley -- Physicists at the University of California, Berkeley, have built the smallest radio yet - a single carbon nanotube one ten-thousandth the diameter of a human hair that requires only a battery and earphones to tune in to your favorite station.

The scientists successfully received their first FM broadcast last year - Derek & The Dominos' "Layla" and the Beach Boys' "Good Vibrations" transmitted from across the room. In homage to last year's 100th anniversary of the first voice and music radio transmission, they also transmitted and successfully tuned in to the first music piece broadcast in 1906, "Largo" from George Frederic Handel's opera "Xerxes."

"We were just in ecstasy when this worked," said team leader Alex Zettl, UC Berkeley professor of physics. "It was fantastic."

The nanoradio, which is currently configured as a receiver but could also work as a transmitter, is 100 billion times smaller than the first commercial radios, and could be used in any number of applications - from cell phones to microscopic devices that sense the environment and relay information via radio signals, Zettl said. Because it is extremely energy efficient, it would integrate well with microelectronic circuits.

"The nanotube radio may lead to radical new applications, such as radio-controlled devices small enough to exist in a human's bloodstream," the authors wrote in a paper published online today by the journal Nano Letters. The paper will appear in the print edition of Nano Letters later this month.

Authors of the nanoradio paper are Zettl, graduate student Kenneth Jensen, and their colleagues in UC Berkeley's Center of Integrated Nanomechanical Systems (COINS) and in the Materials Sciences Division at Lawrence Berkeley National Laboratory (LBNL). COINS is a Nanoscale Science and Engineering Research Center supported by the National Science Foundation (NSF).

Nanotubes are rolled-up sheets of interlocked carbon atoms that form a tube so strong that some scientists have suggested using a nanotube wire to tether satellites in a fixed position above Earth. The nanotubes also exhibit unusual electronic properties because of their size, which, for the nanotubes used in the radio receiver, are about 10 nanometers in diameter and several hundred nanometers long. A nanometer is one billionth of a meter; a human hair is about 50,000-100,000 nanometers in diameter.

In the nanoradio, a single carbon nanotube works as an all-in-one antenna, tuner, amplifier and demodulator for both AM and FM. These are separate components in a standard radio. A demodulator removes the AM or FM carrier frequency, which is in the kiloHertz and megaHertz range, respectively, to retrieve the lower frequency broadcast information.

The nanoradio detects radio signals in a radically new way - it vibrates thousands to millions of times per second in tune with the radio wave. This makes it a true nanoelectromechanical device, dubbed NEMS, that integrates the mechanical and electrical properties of nanoscale materials.

In a normal radio, ambient radio waves from different transmitting stations generate small currents at different frequencies in the antenna, while a tuner selects one of these frequencies to amplify. In the nanoradio, the nanotube, as the antenna, detects radio waves mechanically by vibrating at radio frequencies. The nanotube is placed in a vacuum and hooked to a battery, which covers its tip with negatively charged electrons, and the electric field of the radio wave pushes and pulls the tip thousands to millions of times per second.

While large objects, like a stiff wire or a wooden ruler pinned at one end, vibrate at low frequencies - between tens and hundreds of times per second - the tiny nanotubes vibrate at high frequencies ranging from kiloHertz (thousands of times per second) to hundreds of megaHertz (100 million times per second). Thus, a single nanotube naturally selects only one frequency.

Although it might seem that the vibrating nanotube yields a "one station" radio, the tension on the nanotube also influences its natural vibration frequency, just as the tension on a guitar string fine tunes its pitch. As a result, the physicists can tune in a desired frequency or station by "pulling" on the free tip of the nanotube with a positively charged electrode. This electrode also turns the nanotube into an amplifier. The voltage is high enough to pull electrons off the tip of the nanotube and, because the nanotube is simultaneously vibrating, the electron current from the tip is an amplified version of the incoming radio signal. This is similar to the field-emission amplification of old vacuum tube amplifiers used in early radios and televisions, Zettl said. The amplified output of this simple nanotube device is enough to drive a very sensitive earphone.

Finally, the field-emission and vibration together also demodulate the signal.

"I hate to sound like I'm selling a Ginsu knife - But wait, there's more! It also slices and dices! - but this one nanotube does everything; it performs all radio functions simultaneously and extremely efficiently," Zettl said. "It's ridiculously simple - that's the beauty of it."

Zettl's team assembles the nanoradios very simply, too. From nanotubes copiously produced in a carbon arc, they glue several to a fixed electrode. In a vacuum, they bring the electrode within a few microns of a second electrode, close enough for electrons to jump to it from the closest nanotube and create an electrical circuit. To achieve the desired length of the active nanotube, the team first runs a large current through the nanotube to the second electrode, which makes carbon atoms jump off the tip of the nanotube, trimming it down to size for operation within a particular frequency band. Connect a battery and earphones, and voila!

Reception by the initial radios is scratchy, which Zettl attributes in part to insufficient vacuum. In future nanoradios, a better vacuum can be obtained by insuring a cleaner environment, or perhaps by encasing the single nanotube inside a second, larger non-conducting nanotube, thereby retaining the nanoscale.

Zettl won't only be tuning in to oldies stations with his nanoradio. Because the radio static is actually the sound of atoms jumping on and off the tip of the nanotube, he hopes to use the nanoradio to sense the identity of atoms or even measure their masses, which is done today by cumbersome large mass spectrometers.

###

Coauthors with Jensen and Zettl are UC Berkeley post-doctoral fellow Jeff Weldon and physics graduate student Henry Garcia. The work was supported by NSF and the U.S. Department of Energy.

Nuclear power worldwide: status and outlook

2007-10-24T01:06:00.001-07:00

Nuclear power is expected to raise to a maximum of 679MWe to a minimum of 447MWe from the present 370MWe by 2030.Nuclear power's share of worldwide electricity production rose from less than 1 percent in 1960 to 16 percent in 1986, and that percentage has held essentially constant in the 21 years since 1986.The IAEA report released on October 23, 2007 reviews the status of nuclear power worldwide.

K.S.Parthasarathy

Public release date: 23-Oct-2007

Contact: Press Office
press@iaea.org
0043-126-002-1273
International Atomic Energy Agency
Nuclear power worldwide: status and outlook
A report from the IAEA

The IAEA makes two annual projections concerning the growth of nuclear power, a low and a high. The low projection assumes that all nuclear capacity that is currently under construction or firmly in the development pipeline gets completed and attached to the grid, but no other capacity is added. In this low projection, there would be growth in capacity from 370 GW(e) at the end of 2006 to 447 GW(e) in 2030. (A gigawatt = 1000 megawatts = 1 billion watts)

In the IAEA's high projection -- which adds in additional reasonable and promising projects and plans -- global nuclear capacity is estimated to rise to 679 GW(e) in 2030. That would be an average growth rate of about 2.5%/yr.

"Our job is not so much to predict the future but to prepare for it, " explains the IAEA's Alan McDonald, Nuclear Energy Analyst. "To that end we update each year a high and low projection to establish the range of uncertainty we ought to be prepared for."

Nuclear power's share of worldwide electricity production rose from less than 1 percent in 1960 to 16 percent in 1986, and that percentage has held essentially constant in the 21 years since 1986. Nuclear electricity generation has grown steadily at the same pace as overall global electricity generation. At the close of 2006, nuclear provided about 15 percent of total electricity worldwide.

The IAEA's other key findings as of the end of 2006 are elaborated below.

There were 435 operating nuclear reactors around the world, and 29 more were under construction. The US had the most with 103 operating units. France was next with 59. Japan followed with 55, plus one more under construction, and Russia had 31 operating, and seven more under construction.

Of the 30 countries with nuclear power, the percentage of electricity supplied by nuclear ranged widely: from a high of 78 percent in France; to 54 percent in Belgium; 39 percent in Republic of Korea; 37 percent in Switzerland; 30 percent in Japan; 19 percent in the USA; 16 percent in Russia; 4 percent in South Africa; and 2 percent in China.

Present nuclear power plant expansion is centred in Asia: 15 of the 29 units under construction at the end of 2006 were in Asia. And 26 of the last 36 reactors to have been connected to the grid were in Asia. India currently gets less than 3% of its electricity from nuclear, but at the end of 2006 it had one-quarter of the nuclear construction - 7 of the world's 29 reactors that were under construction. India's plans are even more impressive: an 8-fold increase by 2022 to 10 percent of the electricity supply and a 75-fold increase by 2052 to reach 26 percent of the electricity supply. A 75-fold increase works out to an average of 9.4 percent/yr, about the same as average global nuclear growth from 1970 through 2004. So it's hardly unprecedented.

China is experiencing huge energy growth and is trying to expand every source it can, including nuclear power. It has four reactors under construction and plans a nearly five-fold expansion by just 2020. Because China is growing so fast this would still amount to only 4 percent of total electricity.

Russia had 31 operating reactors, five under construction and significant expansion plans. There's a lot of discussion in Russia of becoming a full fuel-service provider, including services like leasing fuel, reprocessing spent fuel for countries that are interested, and even leasing reactors.

Japan had 55 reactors in operation, one under construction, and plans to increase nuclear power's share of electricity from 30 percent in 2006 to more than 40 percent within the next decade.

South Korea connected its 20th reactor just last year, has another under construction and has broken ground to start building two more. Nuclear power already supplies 39 percent of its electricity.

Europe is a good example of "one size does not fit all." Altogether it had 166 reactors in operation and six under construction. But there are several nuclear prohibition countries like Austria, Italy, Denmark and Ireland. And there are nuclear phase-out countries like Germany and Belgium.

There are also nuclear expansion programmes in Finland, France, Bulgaria and Ukraine. Finland started construction in 2005 on Olkiluoto-3, which is the first new Western European construction since 1991. France plans to start its next plant in 2007.

Several countries with nuclear power are still pondering future plans. The UK, with 19 operating plants, many of which are relatively old, had been the most uncertain until recently. Although a final policy decision on nuclear power will await the results of a public consultation now underway, a White Paper on energy published in May 20071 concluded that "…having reviewed the evidence and information available we believe that the advantages [of new nuclear power] outweigh the disadvantages and that the disadvantages can be effectively managed. On this basis, the Government's preliminary view is that it is in the public's interest to give the private sector the option of investing in new nuclear power stations."

###

1 http://www.dti.gov.uk/energy/whitepaper/page39534.html

The US had 103 reactors providing 19 percent of the country's electricity. For the last few decades the main developments have been improved capacity factors, power increases at existing plants and license renewals. Currently 48 reactors have already received 20-year renewals, so their licensed lifetimes are 60 years. Altogether three-quarters of the US reactors either already have license renewals, have applied for them, or have stated their intention to apply. There have been a lot of announced intentions (about 30 new reactors' worth) and the Nuclear Regulatory Commission is now reviewing four Early Site Permit applications.

For further information, please contact: IAEA Division of Public Information, Media & Outreach Section 43-1-2600-21273 .

For further details on the current status of the nuclear industry, go to IAEA's "Power Reactor Information System,"(PRIS).

Video B-roll is available on request.

Audio Q & A with IAEA Nuclear Energy Analyst, Alan McDonald and UN language editions of this press release are available under the following link http://www.iaea.org/NewsCenter/PressReleases/2007/prn200719.html

Quantitative PET imaging finds early determination of effectiveness of cancer treatment

2007-10-24T00:52:00.000-07:00

PET imaging can demonstrate the effectiveness of cancer treatment.This imaging modality will reveal reduction in metabolism of cells killed by chemotherapeutic agents

K.S.Parthasarathy

Public release date: 23-Oct-2007

Contact: Maryann Verrillo
mverrillo@snm.org
703-652-6773
Society of Nuclear Medicine
Quantitative PET imaging finds early determination of effectiveness of cancer treatment
Visual analysis of PET Scans for non-Hodgkin lymphoma may be improved by using standardized uptake value in monitoring response to treatment, say researchers in October Journal of Nuclear Medicine

RESTON, Va.—With positron emission tomography (PET) imaging, seeing is believing: Evaluating a patient’s response to chemotherapy for non-Hodgkin lymphoma (NHL) typically involves visual interpretation of scans of cancer tumors. Researchers have found that measuring a quantitative index—one that reflects the reduction of metabolic activity after chemotherapy first begins—adds accurate information about patients’ responses to first-line chemotherapy, according to a study in the October issue of the Journal of Nuclear Medicine.

“In our study, we demonstrated that a quantitative assessment of therapeutic response for patients with diffuse large B-cell lymphoma (DLBCL) is more accurate than visual analysis alone when using the radiotracer FDG (fluorodeoxyglucose) with PET scans,” said Michel Meignan, professor of nuclear medicine at Henri Mondor Hospital in Creteil, France. “The ability to predict tumor response early in the course of treatment is very valuable clinically, allowing intensification of treatment in those patients who are unlikely to response to first-line chemotherapy,” he added. “Similarly, treatment could possibly be shortened in those patients who show a favorable response after one or two cycles of chemotherapy, and quantification also may help identify the disease’s transformation from low-grade to aggressive stage,” he explained. “However, visual interpretation of PET scans will always be the first step of analysis and will prevail in case of difficulties to quantify images,” added Meignan.

Diffuse large B-cell lymphoma is a fast-growing, aggressive form of non-Hodgkin lymphoma, a cancer of the body’s lymphatic system. Although there are more than 20 types of NHL, DLBCL is the most common type, making up about 30 percent of all lymphomas. In the United States, about 63,190 people are expected to be diagnosed with non-Hodgkin lymphoma in 2007, according to recent statistics.

Ninety-two patients with DLBCL were studied before and after two cycles of chemotherapy, and tumor response was assessed visually and by various quantitative parameters, explained the co-author of “Early 18F-FDG PET for Prediction of Prognosis in Patients With Diffuse Large B-Cell Lymphoma: SUV-Based Assessment Versus Visual Analysis.” Meignan said, “We found that quantification of tumor FDG uptake (the ratio of tissue radioactivity concentration) can markedly improve the accuracy of FDG PET for prediction of patient outcome.” Additional studies need to be done, said Meignan, reiterating that the future monitoring of cancer tumor response will probably include a combination of quantitative analysis and visual assessment.

PET is a powerful molecular imaging procedure that uses very small amounts of radioactive materials that are targeted to specific organs, bones or tissues. When PET is used to image cancer, a radiopharmaceutical (such as FDG, which includes both a sugar and a radionuclide) is injected into a patient. Cancer cells metabolize sugar at higher rates than normal cells, and the radiopharmaceutical is drawn in higher amounts to cancerous areas. PET scans show where FDG is by tracking the gamma rays given off by the radionuclide tagging the drug and producing three-dimensional images of their distribution within the body. PET scanning provides information about the body’s chemistry, metabolic activity and body function.

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“Early 18F-FDG PET for Prediction of Prognosis in Patients With Diffuse Large B-Cell Lymphoma: SUV-Based Assessment Versus Visual Analysis” appears in the October issue of the Journal of Nuclear Medicine, which is published by SNM, the world’s largest molecular imaging and nuclear medicine society. Additional co-authors include Chieh Lin, Alain Luciani and Alain Rahmouni, Department of Radiology; Emmanuel Itti and Gaetano Paone, Department of Nuclear Medicine; and Corinne Haioun and Jehan Dupuis, Department of Hematology, all at Henri Mondor Hospital in Créteil, France; and Yolande Petegnief and Jean-Noël Talbot, Department of Nuclear Medicine, Tenon Hospital in Paris, France.

Credentialed press: To obtain a copy of this article—and online access to the Journal of Nuclear Medicine— please contact Maryann Verrillo by phone at (703) 652-6773 or send an e-mail to mverrillo@snm.org. Current and past issues of the Journal of Nuclear Medicine can be found online at http://jnm.snmjournals.org. Print copies can be obtained by contacting the SNM Service Center, 1850 Samuel Morse Drive, Reston, VA 20190-5316; phone (800) 513-6853; e-mail servicecenter@snm.org; fax (703) 708-9015. A subscription to the journal is an SNM member benefit.

About SNM—Advancing Molecular Imaging and Therapy

SNM is an international scientific and professional organization of more than 16,000 members dedicated to promoting the science, technology and practical applications of molecular and nuclear imaging to diagnose, manage and treat diseases in women, men and children. Founded more than 50 years ago, SNM continues to provide essential resources for health care practitioners and patients; publish the most prominent peer-reviewed journal in the field (Journal of Nuclear Medicine); host the premier annual meeting for medical imaging; sponsor research grants, fellowships and awards; and train physicians, technologists, scientists, physicists, chemists and radiopharmacists in state-of-the-art imaging procedures and advances. SNM members have introduced—and continue to explore—biological and technological innovations in medicine that noninvasively investigate the molecular basis of diseases, benefiting countless generations of patients. SNM is based in Reston, Va.; additional information can be found online at http://www.snm.org.

UT rheumatologists discover 2 genes related to disabling form of arthritis

2007-10-22T01:54:00.000-07:00

Genetics of arthritis

John D. Reveille, M.D., University of Texas Medical School at Houston.

Public release date: 21-Oct-2007
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Contact: Meredith Raine
Meredith.Raine@uth.tmc.edu
713-500-3030
University of Texas Health Science Center at Houston
UT rheumatologists discover 2 genes related to disabling form of arthritis

HOUSTON – (Oct. 22, 2007)—Work done in part by researchers at The University of Texas Medical School at Houston has led to the discovery of two genes that cause ankylosing spondylitis, an inflammatory and potentially disabling disease. The findings are published in the Oct. 21 online edition of Nature Genetics, a journal that emphasizes research on the genetic basis for common and complex diseases.

John D. Reveille, M.D., professor and director of the Division of Rheumatology and Clinical Immunogenetics, in conjunction with Matthew A. Brown, M.D., professor of immunogenetics at Australia’s University of Queensland, led research done by the Triple “A” Spondylitis Consortium Genetic Study (i.e. the TASC or Australo-Anglo-American Spondylitis Consortium).

The international team of researchers worked with investigators from the British Wellcome Trust Case Control Consortium, and together they made the genetic discovery.

Reveille, chief of rheumatology at Memorial Hermann – Texas Medical Center, said the discovery of genes ARTS1 and IL23R brings the scientific community two steps closer to fully understanding ankylosing spondylitis or AS, a chronic form of arthritis that attacks the spine and also can target other joints and organs in the body.

“We’ve long known that the HLA-B27 gene accounts for 40 percent of the overall cause of AS,” said Reveille, the principal investigator of TASC. “Now we have found two new genes. Together with HLA-B27, these genes account for roughly 70 percent of the overall cause. That means we’ve almost nailed this disease. Within the next year, I predict we will have identified all the genes that play a role in this insidious disease. There is more exciting news to come.”

The recent discovery is based on work from the largest and most comprehensive genome-wide association scan conducted to date. In this part of the research project, investigators were searching for genetic information related to AS, as well as autoimmune thyroid disease/Graves’ Disease, breast cancer and multiple sclerosis. Reveille, the George S. Bruce, Jr. Professor in Arthritis and Other Rheumatic Diseases, said the most significant findings were in AS, a disease that generally strikes patients in their teens, 20s or 30s.

ARTS1 and IL23R show a new pathway of causation, Reveille said, and this could lead to new therapies for the arthritic condition, which can cause a complete fusion of the spine, leaving patients unable to straighten and bend.

The identification of the two new genes also could help physicians identify patients who are at the highest risk for developing AS.

“For example, if you have a family member with AS, a simple blood test would be able to tell us if you are also at risk,” Reveille said. “We could offer screenings for people with back pain. In the past, the HLA-B27 test was all we had. Now we potentially have more tests.”

Steve Haskew, who has lived with AS for thirty years, said the genetic discovery offers hope to patients – especially those who are newly diagnosed.

“When I first started experiencing problems – lower back pain, the aching joints – no one could tell me what was wrong,” said Haskew, 59, co-leader of an AS support group that meets every other month at the UT Medical School at Houston. “It took 10 years before a rheumatologist diagnosed me with AS. Back then, there weren’t many options. I was told to take anti-inflammatories and stay as active as possible. It’s fascinating to see how far we’ve come and how much has been learned about the disease since then.”

The research done by Reveille and his colleague Xiaodong Zhou, M.D., associate professor of medicine in Division of Rheumatology and Clinical Immunogenetics, was supported in part by the Center for Clinical and Translational Sciences (CCTS) at The University of Texas Health Science Center at Houston.

“This is a success story for genetics work, and I think it will lead the way for other work to be done,” Reveille said.

The Spondylitis Association of America (SAA) oversaw the nationwide recruitment of patients and families for the study.

“This is the most significant breakthrough in AS genetic research since HLA-B27 was uncovered 34 years ago, and SAA played a significant role in making the study possible,” said SAA Associate Executive Director Laurie Savage, who is co-principal investigator for TASC’s administrative core.

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Cockroaches are morons in the morning, geniuses in the evening

2007-09-28T01:33:00.000-07:00

The fact that scientists can teach cockroaches lessons is itself very interesting
K.S.Parthasarathy

Public release date: 27-Sep-2007

Contact: David F. Salisbury
david.salisbury@vanderbilt.edu
615-343-6803
Vanderbilt University
Cockroaches are morons in the morning, geniuses in the evening

In its ability to learn, the cockroach is a moron in the morning and a genius in the evening.

Dramatic daily variations in the cockroach’s learning ability were discovered by a new study performed by Vanderbilt University biologists and published online this week in the Proceedings of the National Academy of Sciences.

“This is the first example of an insect whose ability to learn is controlled by its biological clock,” says Terry L. Page, the professor of biological sciences who directed the project. Undergraduate students Susan Decker and Shannon McConnaughey also participated in the study.

The few studies that have been done with mammals suggest their ability to learn also varies with the time of day. For example, a recent experiment with humans found that people’s ability to acquire new information is reduced when their biological clocks are disrupted, particularly at certain times of day. Similarly, several learning and memory studies with rodents have found that these processes are modulated by their circadian clocks. One study in rats associated jet lag with retrograde amnesia.

In the current study, the researchers taught individual cockroaches to associate peppermint – a scent that they normally find slightly distasteful – with sugar water, causing them to favor it over vanilla, a scent they find universally appealing.

The researchers trained individual cockroaches at different times in the 24-hour day/night cycle and then tested them to see how long they remembered the association. They found that the individuals trained during the evening retained the memory for several days. Those trained at night also had good retention. During the morning, however, when the cockroaches are least active, they were totally incapable of forming a new memory, although they could recall memories learned at other times.

“It is very surprising that the deficit in the morning is so profound,” says Page. “An interesting question is why the animal would not want to learn at that particular time of day. We have no idea.”

Most previous studies of circadian rhythm have focused on the visual system. “The advantage of eyes becoming more sensitive at night is so obvious that people haven’t looked much at other sensory systems,” says Page. “The fact that our study involves the olfactory system suggests that the circadian cycle could be influencing a number of senses beyond vision.”

In the study, the researchers used cockroaches of the species Leucophaea maderae. It doesn’t have a common name but it is commonly used in scientific experiments because it was used extensively in early physiological and endocrinological studies.

The discovery that the cockroach’s memory is so strongly modulated by its circadian clock opens up new opportunities to learn more about the molecular basis of the interaction between biological clocks and memory and learning in general.

Much of the new information about the molecular basis of memory and learning has come from the study of other invertebrates (animals without backbones) such as the sea slug (Apylsia) and the fruit fly (Drosophila).

“Studies like this suggest that time of day can have a profound impact, at least in certain situations. By studying the way the biological clock modulates learning and memory we may learn more about how these processes take place and what can influence them,” Page says.

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[Note: A multimedia version of this story is available on Exploration, Vanderbilt University’s online research magazine, at http://www.vanderbilt.edu/exploration/stories/cockroach.html.]

Nature explains the cell-making process

2007-09-24T09:12:00.000-07:00

Published online: 21 September 2007; | doi:10.1038/news070917-11
Why a person doesn't evolve in one lifetime
The body's complicated cell-making process may help to avoid cancer.

Philip Ball

What if your skin cells evolved every time they grew to replace dead skin?
STEVE GSCHMEISSNER / SCIENCE PHOTO LIBRARY
It's not easy making a human. Getting from a fertilized egg to a full-grown adult involves a near-miracle of orchestration, with replicating cells acquiring specialized functions in just the right places at the right times. So you'd think that, having done the job once, our bodies would replace cells when required by the simplest means possible.

Oddly, they don't. Our tissues don't renew themselves by mere copying, with old skin cells dividing into new skin cells and so forth. Instead, they keep repeating the laborious process of starting each cell from scratch. Now scientists think they know why: it could be nature's way of making sure that we don't evolve as we grow older1.

Evolution is usually thought of as something that happens to whole organisms. But there's no fundamental reason why, for multicelled organisms, it shouldn't happen within a single organism too.

In a colony of single-celled bacteria, researchers can watch evolution in action. As the cells divide, mutants appear; and under stress, there is a selective pressure that favours some mutants over others, spreading advantageous genetic changes through the population.

In principle, precisely the same thing could occur throughout our bodies. Our cells are constantly being replaced in vast numbers: the human body typically contains about a hundred trillion cells, and many billions are shed and replaced every day.

If this happened simply by replication of the various specialized cells in each tissue, our tissues would evolve: mutations would arise, and some would spread. In particular, mutant cells that don't do their specialized job so well tend to replicate more quickly than non-mutants, and so gain a competitive advantage, freeloading off the others. In such a case, our wonderfully wrought bodies could grind to a halt.

Avoiding fate

While working at the Santa Fe Institute in New Mexico, evolutionary biologist John Pepper of the University of Arizona in Tucson and his co-workers came up with a theory for how multicelled organisms avoid this fate. They say it explains why the epithelial tissue cells that line all parts of the body take such an apparently long-winded route to replication, rather than just copying themselves in their mature form.

To renew themselves, epithelial tissues retain a population of undifferentiated stem cells, like the unformed cells present in embryos, that have the ability to grow into different types of cells. When replacements are needed, some of these stem cells divide to make transient amplifying cells (TACs). The TACs then divide several times, and Pepper and his co-workers think that each division produces cells that are a little more developed into mature tissue cells.

All this costs a lot of metabolic energy, so it is not very efficient. But, the researchers say, it means that the functions of self-replication and proliferation are divided between separate groups of cells. The stem cells replicate, but only a little, and so there's not much chance for mutations to arise or for selective pressure to fix them in place. The proliferating TACS may mutate, but they aren't simply copying themselves, so there isn't any direct competition between the cells to create an evolutionary pressure. As a result, evolution can't get started.

Pepper and his colleagues have used computer modelling to show that this proposed mechanism can suppress evolution in a long-lived, multicelled organism.

Inside job

One case in which this scheme might not operate, they say, is in the immune system. Here evolution is beneficial, as it introduces adaptations that fight previously encountered invaders.

One drawback of this, however, is that it would be expected to make the immune system more prone to cancers. And that seems to be so: leukaemia and lymphoma are cancers associated with the immune system, and they seem to be more common in younger people than many other cancers, suggesting that the failure to suppress evolution allows its problems to show up rather quickly.

The researchers think that their hypothesis could provide new insights into cancers more generally. Whereas conventional wisdom has it that cancer is caused by some genetic mutation that leads cells to proliferate uncontrollably, this new picture implies that the problem would lie with TAC mutations that interfere with differentiation — so that a TAC cell ends up just copying itself instead of producing cells on the next rung up on the way to mature tissue cells.

Carlo Maley, Pepper's colleague at the Wistar Institute, a biomedical research centre in Philadelphia, Pennsylvania, says that if their picture is right, incipient cancer formation might be detected very early by looking for biomolecules in body fluids that signal disruption of cell differentiation, even before there are any physical signs of tumour growth.

Visit our newsblog to read and post comments about this story.

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References

1. Pepper, J. W., et al. PLoS Comput. Biol. (in the press).

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http://news.nature.com//news/2007/070917/070917-11.html

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Vitamin C essential for plant growth

2007-09-24T00:57:00.000-07:00

In a study published in the on line edition of The Plant Journal,the scientists from the University of Exeter and Shimane University in Japan have proved for the first time that vitamin C is essential for plant growth.

K.S.Parthasarathy

Public release date: 23-Sep-2007

Contact: Sarah Hoyle
s.hoyle@exeter.ac.uk
44-013-922-62062
University of Exeter
Study shows vitamin C is essential for plant growth

Scientists from the University of Exeter and Shimane University in Japan have proved for the first time that vitamin C is essential for plant growth. This discovery could have implications for agriculture and for the production of vitamin C dietary supplements.

The study, which is now published online in The Plant Journal, describes the newly-identified enzyme, GDP-L-galactose phosphorylase, which produces vitamin C, or ascorbate, in plants. Vitamin C is already known to be an antioxidant, which helps plants deal with stresses from drought to ozone and UV radiation, but until now it was not known that plants could not grow without it.

Professor Nicholas Smirnoff of the University of Exeter, lead author on the paper said: ‘Vitamin C is the most abundant antioxidant in plants and yet its functions are poorly understood. By discovering that the new enzyme is encoded by two genes, we were able to engineer vitamin C-free plants and found that they were unable to grow.’

The discovery also identifies the new enzyme as a key player in controlling vitamin C accumulation in response to light. Vitamin C provides protection against the harmful side-effects of light during photosynthesis, the process by which light energy is used to convert carbon dioxide into plant matter.

Professor Nicholas Smirnoff continued: ‘The discovery is exciting for me because it is the culmination of a long-term research programme on vitamin C in plants at the University of Exeter. It opens new opportunities to understand fundamental growth processes in plants and to improve plant resistance to stresses in a changing climate. In the longer term I hope that it will contribute to the efforts of plant scientists to improve crop yield in a sustainable manner.’

The findings could also pave the way for a new approach to producing vitamin C dietary supplements. In Britain we spend an estimated £20 million on vitamin C tablets each year, making this the most widely-used dietary supplement. Vitamin C is currently produced by mixed fermentation and chemical synthesis. The new enzyme provides the potential to engineer microbes to produce vitamin C by a simpler one-step process.

###

This research was funded by Bio-Technical Resources, Exeter University School of Biosciences, the Japan Society for the Promotion of Science and a Biotechnology and Biological Sciences Research Council (BBSRC) studentship.

Proposal defining kilogramme as a precise number of carbon atoms

2007-09-22T08:18:00.000-07:00

Ronald F. Fox, a Regents’ Professor Emeritus in the School of Physics at the Georgia Institute of Technology and Theodore P. Hill – a Professor Emeritus in the Georgia Tech School of Mathematics proposed that the gram – 1/1000th of a kilogram – would henceforth be defined as the mass of exactly 18 x 14074481 (cubed) carbon-12 atoms.

The new definition needed a precise value for the Avagadro's number.In the fall of 2006 Fox and Hill submitted a paper to Physics Archives in which they proposed assigning a specific number to the constant – one of about 10 possible values within the experimental range. The authors pointed out that a precise Avogadro’s constant could also precisely redefine the measure of mass, the kilogram.The authors conceded that a precise Avogadro’s constant could also precisely redefine the measure of mass, the kilogram. The duo got inspired further when Associated Press (September 2007) noted that the mass of the official kilogramme cast 118 years is disappearing.The loss was 50 microgramme at the last check.

K.S.Parthasarathy

Public release date: 21-Sep-2007

Contact: John Toon
jtoon@gatech.edu
404-894-6986
Georgia Institute of Technology Research News
A better definition for the kilogram? Scientists propose a precise number of carbon atoms

How much is a kilogram?

It turns out that nobody can say for sure, at least not in a way that won’t change ever so slightly over time. The official kilogram – a cylinder cast 118 years ago from platinum and iridium and known as the International Prototype Kilogram or “Le Gran K” – has been losing mass, about 50 micrograms at last check. The change is occurring despite careful storage at a facility near Paris.

That’s not so good for a standard the world depends on to define mass.

Now, two U.S. professors – a physicist and mathematician – say it’s time to define the kilogram in a new and more elegant way that will be the same today, tomorrow and 118 years from now. They’ve launched a campaign aimed at redefining the kilogram as the mass of a very large – but precisely-specified – number of carbon-12 atoms.

“Our standard would eliminate the need for a physical artifact to define what a kilogram is,” said Ronald F. Fox, a Regents’ Professor Emeritus in the School of Physics at the Georgia Institute of Technology. “We want something that is logically very simple to understand.”

Their proposal is that the gram – 1/1000th of a kilogram – would henceforth be defined as the mass of exactly 18 x 14074481 (cubed) carbon-12 atoms.

The proposal, made by Fox and Theodore P. Hill – a Professor Emeritus in the Georgia Tech School of Mathematics – first assigns a specific value to Avogadro’s constant. Proposed in the 1800s by Italian scientist Amedeo Avogadro, the constant represents the number of atoms or molecules in one mole of a pure material – for instance, the number of carbon-12 atoms in 12 grams of the element. However, Avogadro’s constant isn’t a specific number; it’s a range of values that can be determined experimentally, but not with enough precision to be a single number.

Spurred by Hill’s half-serious question about whether Avogadro’s constant was an even or odd number, in the fall of 2006 Fox and Hill submitted a paper to Physics Archives in which they proposed assigning a specific number to the constant – one of about 10 possible values within the experimental range. The authors pointed out that a precise Avogadro’s constant could also precisely redefine the measure of mass, the kilogram.

Their proposal drew attention from the editors of American Scientist, who asked for a longer article published in March 2007. The proposal has so far drawn five letters, including one from Paul J. Karol, chair of the Committee on Nomenclature, Terminology and Symbols of the American Chemical Society. Karol added his endorsement to the proposal and suggested making the number divisible by 12 – which Fox and Hill did in an addendum by changing their number’s final digit from 8 to 6. So the new proposal for Avogadro’s constant became 84446886 (cubed), still within the range of accepted values.

Fast-forward to September 2007, when Fox read an Associated Press article on the CNN.com Web site about the mass disappearing from the International Prototype Kilogram. While the AP said the missing mass amounted to no more than “the weight of a fingerprint,” Fox argues that the amount could be significant in a world that is measuring time in ultra-sub-nanoseconds and length in ultra-sub-nanometers.

So Fox and Hill fired off another article to Physics Archive, this one proposing to redefine the gram as 1/12th the mass of a mole of carbon 12 – a mole long being defined as Avogrado’s number of atoms. They now hope to generate more interest in their idea for what may turn out to be a competition of standards proposals leading up to a 2011 meeting of the International Committee for Weights and Measures.

At least two other proposals for redefining the kilogram are under discussion. They include replacing the platinum-iridium cylinder with a sphere of pure silicon atoms, and using a device known as the “watt balance” to define the kilogram using electromagnetic energy. Both would offer an improvement over the existing standard – but not be as simple as what Fox and Hill have proposed, nor be exact, they say.

“Using a perfect numerical cube to define these constants yields the same level of significance – eight or nine digits – as in those integers that define the second and the speed of light,” Hill said. “A purely mathematical definition of the kilogram is experimentally neutral – researchers may then use any laboratory method they want to approximate exact masses.”

The kilogram is the last major standard defined by a physical artifact rather than a fundamental physical property. In 1983, for instance, the distance represented by a meter was redefined by how far light travels in 1/299,792,458 seconds – replacing a metal stick with two marks on it.

“We suspect that there will be some public debate about this issue,” Fox said. “We want scientists and science teachers and others to think about this problem because we think they can have an impact. Public discussion may play an important role in determining how one of the world’s basic physical constants is defined.”

How important is this issue to the world’s future technological development"

“When you make physical and chemical measurements, it’s important to have as high a precision as possible, and these standards really define the limits of precision,” Fox said. “The lack of an accurate standard leaves some inconsistency in how you state results. Having a unique standard could eliminate that.”

While the new definition would do away with the need for a physical representation of mass, Fox says people who want a physical artifact could still have one – though carbon can’t actually form a perfect cube with the right number of atoms. And building one might take some time.

“You could imagine having a lump of matter that actually had exactly the right number of atoms in it,” Fox noted. “If you could build it by some kind of self-assembly process – as opposed to building it atom-by-atom, which would take a few billion years – you could have new kilogram artifact made of carbon. But there’s really no need for that. Even if you built a perfect kilogram, it would immediately be inaccurate as soon as a single atom was sloughed off or absorbed.”

###

Technical Contacts: Ron Fox (770-433-8950); E-mail: (ron.fox@physics.gatech.edu) or Ted Hill (805-528-1331); E-mail: (hilltp66@charter.net).

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Antibiotics overprescribed by GPs

2007-09-20T01:59:00.000-07:00

Many physicians appear to prescribe antibiotics without applying their mind.Van Duijn suggests that the results of his study should be used to update quality assurance programs and postgraduate courses, to emphasise the use of evidence-based prognostic criteria (e.g. chronic respiratory co-morbidity and old age) as an indication to prescribe antibiotics instead of single signs of inflammation or diagnostic labels.

K.S.Parthasarathy

Public release date: 19-Sep-2007

Contact: Charlotte Webber
press@biomedcentral.com
44-020-763-19980
BioMed Central
Antibiotics overprescribed by GPs

GPs are unnecessarily giving patients antibiotics for respiratory tract (RT) infections which would clear up on their own. Doctors tend to over-emphasise symptoms such as white spots in the throat, rather than looking at factors such as old age and co-morbidity, which would affect a patient's recovery, according to an article published in the online open access journal, BMC Family Practice.

Huug J. van Duijn and his team at the Julius Center for Health Sciences and Primary Care from the University Medical Center Utrecht, The Netherlands, looked at the practice records of 163 GPs from 85 Dutch practices over a 12 month period, and carried out a survey of the doctors' attitudes to prescribing antibiotics for RT infections. Diagnostic labelling (the tendency to encode RT episodes as infections rather than as symptoms) seemed to be an arbitrary process, often used to justify antibiotic prescribing. GPs may give out antibiotics unnecessarily to defend themselves against unforeseen complications, even if these are unlikely to materialize.

Although Dutch GPs prescribe relatively small antibiotic volumes and international colleagues often envy the quality assurance system in Dutch primary care with guidelines and peer review groups, Van Duijn suggests that the results of his study should be used to update quality assurance programs and postgraduate courses, to emphasise the use of evidence-based prognostic criteria (e.g. chronic respiratory co-morbidity and old age) as an indication to prescribe antibiotics instead of single signs of inflammation or diagnostic labels. "Even in the Netherlands there is an over-prescribing of antibiotics; about 50% of the antibiotic prescriptions for acute RT episodes are not in accordance with Dutch national guidelines," says van Duijn. "Considering costs, side-effects and the growing resistance to pathogens, it is important to rationalise antibiotic prescribing as much as possible."

###

Article
Diagnostic labelling and other GP characteristics as determinants of antibiotic prescribing for acute respiratory tract episodes
Huug J. van Duijn, Marijke M. Kuyvenhoven, Hanneke M. Tiebosch, François G. Schellevis and Theo J.M. Verheij
BMC Family Practice (in press)

During the embargo, article available at: http://www.biomedcentral.com/imedia/5436403961360476_article.pdf?random=803709

After the embargo, article available from the journal website at: http://www.biomedcentral.com/bmcfampract/

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Academy releases emergency preparedness tools to offer shelter to millions of people

2007-09-14T00:48:00.000-07:00

In spite of spending billions of dollars for drawing emergency preparedness plans, millions of people are at risk in USA.This is primarily because they do not account for critical problems people face when they actually try to protect themselves.The New York Academy of Medicine today released a report and tools—available at www.redefiningreadiness.

K.S.Parthasarathy

Public release date: 13-Sep-2007

Contact: Kathryn Cervino
kcervino@nyam.org
212-822-7285
New York Academy of Medicine
Academy releases emergency preparedness tools to enable millions more people to shelter in place
Online 'Redefining Readiness' tools harness the public's knowledge to address a fundamental flaw in planning
New academy tools help people prepare to shelter in place in the face of emergencies.

Although the nation has invested billions of dollars preparing to respond to emergencies, current plans leave millions of Americans at risk because they do not account for critical problems people face when they actually try to protect themselves. To fix this fundamental flaw, The New York Academy of Medicine is today releasing a report and tools—available at www.redefiningreadiness.net—that will enable households, work places, schools and early childhood/youth programs, and governments to anticipate and address problems they would face in emergencies. The tools are released during National Preparedness Month, an initiative of the U.S. Department of Homeland Security.

The report, With the Public’s Knowledge, We Can Make Sheltering in Place Possible, is based on two years’ work gathering the insights and experiences of nearly 2,000 people who live and work in four communities around the country. It identifies serious and unanticipated problems that currently make it neither feasible nor safe for many people to shelter in place. In conjunction with that report, the Academy is releasing four Shelter-in-Place Issue Sets (in both Spanish and English) to help members of households and organizations recognize and address their own vulnerabilities in these kinds of emergencies. Sheltering in place means staying inside whatever building you happen to be in—a workplace, school, store, or at home—for a period of a few hours to several days in order to stay safe, even if that requires you to be separated from other family members.

“Sheltering in place is a very important protective strategy in situations ranging from dirty bombs, toxic explosions, and chemical spills to much more common emergencies, like electrical blackouts and snowstorms,” said Roz D. Lasker, MD, Director of the Academy’s Center for the Advancement of Collaborative Strategies in Health and Division of Public Health, and lead author of the report.

The Academy’s main report documents that the emergency preparedness instructions being given to people and organizations do not address many important sheltering-in-place issues and sometimes make matters worse. Among the many gaps it uncovered:

* The public is being instructed to keep a supply of food and water in their homes, and most keep their medications there as well. But in a shelter-in-place emergency, many people will not be at home and will need to take shelter in other buildings, so their home-supply of food, water, or medicines won’t be accessible.

* The public is being told to identify places for family members to reunite in the event of an emergency. But those instructions don’t address situations in which it might be unsafe to go to such a place, such as if you would have to go through a danger zone to get there.

* While instructions describe how to identify and seal “safe rooms” in homes, schools, and other buildings, they pay little attention to assuring that the rooms can accommodate the number of people who are likely to need shelter, provide them with breathable air and tolerable temperatures, or give them safe access to water, food, lavatories, telephones, and medical supplies.

* Schools have been preparing for emergencies that affect the school directly, but children are also at risk if their parents and other guardians need to shelter in place because of an emergency and no other adult is available to pick the children up or be at home with them after school.

“The disconnect between current instructions and the problems people face in shelter-in-place emergencies isn’t surprising, since the public never had an opportunity to think about these situations in such detail before,” Lasker said.

The Academy has been harnessing the public’s knowledge about emergencies for several years now, with generous support from the W. K. Kellogg Foundation. In 2004, the Academy’s research study, Redefining Readiness: Terrorism Planning Through the Eyes of the Public, predicted that large numbers of people would suffer or die unnecessarily in emergencies, because planners were developing instructions for the public to follow without finding out whether it is actually possible, or safe, for all groups to do so. The prediction was proven to be correct during Hurricane Katrina, when many people could not follow instructions to evacuate due to barriers that had not been identified or addressed beforehand.

Over the past two years, the Academy has been working to prevent such needless death and suffering with teams in four Redefining Readiness demonstration sites in Carlsbad, NM; Chicago, IL; Savannah, GA; and southeast Oklahoma. In more than 200 small group discussions, almost 2,000 residents from diverse backgrounds explored the particular problems they would face trying to protect themselves in shelter-in-place emergencies, and the actions that they and other people and organizations could take. “Because of these efforts, we now know how to protect many more Americans in shelter-in-place emergencies than is currently possible,” said Lasker.

The insights generated in the small group discussions provided the basis for the Academy’s four Shelter-in-Place Issue Sets, which are tailored specifically to people in households, work places, schools and early childhood/youth programs, and governments. These practical tools—which consist of sets of questions rather than instructions—are designed to help users become aware of critical protection problems that their own household or organization can address and to develop workable solutions. The four issue sets are available on-line in Spanish as well as English.

Nan D. Hunter, JD, Director of the Center for Health, Science, and Public Policy at Brooklyn Law School and a co-author of the Academy’s new report, highlighted the importance of these tools for schools and work places. “The issue sets can help these organizations avoid liability by clarifying what they might reasonably be expected to do in shelter-in-place emergencies,” Hunter said. “Government agencies and private philanthropies can go a long way toward helping schools and work places realize those expectations – protecting employees, students, and customers in the process – by integrating the use of the issue sets in their current grant programs and by providing schools and work places with other incentives and supports.”

“This work is an important example of ways in which the Academy can play a role in assuring that individuals and communities affected by policies and programs have a great voice in creating them and thereby making them more effective” said Jo Ivey Boufford, MD, Academy President.

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Founded in 1847, The New York Academy of Medicine is an independent, non-partisan, non-profit institution whose mission is to enhance the health of the public. Our research, education, community engagement, and evidence-based advocacy seek to improve the health of people living in cities, especially disadvantaged and vulnerable populations. The impact of these initiatives reaches into neighborhoods in New York City, across the country, and around the world. We work with community based organizations, academic institutions, corporations, the media, and government to catalyze and contribute to changes that promote health. Visit us online at www.nyam.org.

For more information about National Preparedness Month, an initiative each September of the U.S. Department of Homeland Security designed to encourage Americans to take simple steps to prepare for emergencies in their homes, businesses and schools, visit www.ready.gov.

Mobile phone use not associated with any adverse health effects, new study

2007-09-13T00:26:00.000-07:00

Mobile phone use is increasing at a fast pace. Researchers are involved in intensive studies on the possible adverse health effects of its use.On September 12 as part of its 2007 Report, the Mobile Telecommunications and Health Research (MTHR) Programme concluded that mobile phones have not been found to be associated with any biological or adverse health effects. The research programme included the largest and most robust studies of electrical hypersensitivity undertaken anywhere in the world.

K.S.Parthasarathy

Public release date: 12-Sep-2007

Contact: Science Media Center
44-020-767-02980
University of Nottingham
New report on mobile phone research published

Mobile phones have not been found to be associated with any biological or adverse health effects, according to the UK’s largest investigation into the possible health risks from mobile telephone technology.

The Mobile Telecommunications and Health Research (MTHR) Programme published its conclusions on September 12 as part of its 2007 Report.

The six-year research programme, chaired by Professor Lawrie Challis, Emeritus Professor of Physics at The University of Nottingham, has found no association between short term mobile phone use and brain cancer. Studies on volunteers also showed no evidence that brain function was affected by mobile phone signals or the signals used by the emergency services (TETRA).

The MTHR programme management committee believes there is no need to support further work in this area.

The research programme also included the largest and most robust studies of electrical hypersensitivity undertaken anywhere in the world. These studies have found no evidence that the unpleasant symptoms experienced by sufferers are the result of exposure to signals from mobile phones or base stations.

The situation for longer-term exposure is less clear as studies have so far only included a limited number of participants who have used their phones for ten years or more. The committee recommends more research be conducted in this area.

The MTHR programme also investigated whether mobile phones might affect cells and tissue beyond simply heating them. The results so far show no evidence for this and the committee believes there is no need to support further work in this area.

Professor Lawrie Challis, Chairman of MTHR, said: “This is a very substantial report from a large research programme. The work reported today has all been published in respected peer-reviewed scientific or medical journals.

“The results are so far reassuring but there is still a need for more research, especially to check that no effects emerge from longer-term phone use from adults and from use by children.”

The research programme has also funded some basic measurements of radio signals from microcell and picocell base stations such as those found in airports, railway stations and shopping malls. These have shown that exposures are well below international guidelines.

Additional studies also confirmed that the use of a mobile phone while driving, whether hand-held or hands-free, causes impairment to performance comparable to that from other in-car distractions. There are however indications that the demand on cognitive resources from mobile phones may be greater.

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Details of all the projects supported by the Programme are published on its web site: http://www.mthr.org.uk

Notes to editors:

The University of Nottingham is Britain's University of the Year (The Times Higher Awards 2006). It undertakes world-changing research, provides innovative teaching and a student experience of the highest quality. Ranked by Newsweek in the world's Top 75 universities, its academics have won two Nobel Prizes since 2003. The University is an international institution with campuses in the United Kingdom, Malaysia and China.

The MTHR Programme was set up in response to the research recommendations contained within the ‘Stewart Report’. The Programme received approximately £8.8 million of funding from a variety of government and industry sources.

To ensure the independence of the research, scientific management of the programme was entrusted to an independent Programme Management Committee made up of independent experts, mostly senior university academics. Funds contributed by the sponsors of the Programme are managed on behalf of the Committee by the Department of Health as Secretariat to the Programme.

The first Chairman of the Programme Management Committee was Sir William Stewart and he was succeeded in November 2002 by Professor Lawrie Challis, Emeritus Professor of Physics at the University of Nottingham and formerly Vice-chairman of the Stewart Committee.

The Programme was set up in 2001 and has supported 28 individual research projects, mostly undertaken in UK universities. Of these, 23 have now been completed and most have published results in peer-reviewed scientific and medical journals (23 papers to date, with more expected in the near future). The Report 2007 summarises the state of knowledge at the time of the Stewart Report and the current state of knowledge, taking account of both research supported by the Programme and that carried out elsewhere. It also provides an indication of future research priorities.

More information is available from the Science Media Centre on +44 (0)20 7670 2980 smc@sciencemediacentre.org; or Media Relations Manager Tim Utton in the University’s Media and Public Relations Office on +44 (0)115 846 8092, tim.utton@nottingham.ac.uk. For non-news media enquires call Nigel Cridland – MTHR Scientific Co-ordinator +44 (0)1235 822666 MTHRDL@hpa.org.uk