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February 26, 2007, 6:29 PM CT

Avoiding Carpal Tunnel Syndrome

Avoiding Carpal Tunnel Syndrome
In work involving the hands, whether using a computer or a hammer, the wrist is a vulnerable spot. Repeated or sustained bending and flexing can lead to carpal tunnel syndrome (CTS).

A group of human factors/ergonomics (HF/E) researchers from the University of California at San Francisco and McMaster University in Ontario, Canada, have conducted the first study that systematically identifies how one contributor to CTS carpal tunnel pressure can be examined in detail to establish limits on how much a wrist can be flexed before nerve damage sets in. The researchers believe their findings could be used to create simple guidelines to help workers avoid wrist postures that are likely to cause nerve trauma. The findings from their study appear in a paper in the recent issue of Human Factors: The Journal of the Human Factors and Ergonomics Society.

The research team studied the pressure that is placed on the nerve in the carpal tunnel in various wrist postures in 37 healthy men and women between the ages of 22 and 50. Wrist postures that are not neutral (that is, bent or flexed) cause increased pressure on the nerve. The researchers concluded that when sustained pressure on the carpal tunnel reaches 30 mmHG, injury is likely to occur.

In order to keep pressure below 30 mmHG, it is recommended that sustained wrist extension (bending the hand back) should not exceed 32.7 degrees, wrist flexion (bending the wrist toward the palm) should not exceed 48.6 degrees, ulnar deviation (sideways toward the small finger) should not exceed 14.5 degrees, and radial deviation (sideways toward the thumb) should not exceed 21.8 degrees.........

Posted by: Sean      Read more         Source


February 22, 2007, 10:14 PM CT

New Hydrogen Fuel System

New Hydrogen Fuel System
Northern Nevada energy consumers can be excused if they have a sense of "sticker shock" when their power bills come due following the holiday season. Or, that they have a feeling of powerlessness as the price of gasoline climbs to $3 per gallon.

They wonder: will the days of the $1 tank of gas ever return?

Thanks to research done by a University of Nevada, Reno professor in the area of hydrogen energy generation, soaring power bills could become a thing of the past. And, finding a power source for your car that costs as little as $1 per gallon could also soon become a welcome reality.

Manoranjan Misra, professor of materials science and engineering, recently received a $3 million research grant from the U.S. Department of Energy to continue his groundbreaking work in various forms of renewable energy. Misra's current project focuses on harnessing photoactive material from the sun to generate hydrogen. Hydrogen is one of the cleanest forms of energy, and studies have shown that it is 33 percent more efficient than liquid fuels.

Northern Nevada, with its unusually sunny weather with more than 300 sunny days per year could become the perfect hub to generate hydrogen energy, as per Misra.

"We can utilize this great energy resource to our advantage to produce hydrogen," Misra said. "We are uniquely positioned in Northern Nevada, as the average energy from the sun is around one kilowatt per square meter area. In Reno it is much higher than that. Because it is so bright and sunny here in Reno, we have in a number of ways the perfect location for photo-hydrogen generation".........

Posted by: Sarah      Read more         Source


February 21, 2007, 9:39 PM CT

Solving Cellular Mating Puzzle

Solving Cellular Mating Puzzle Credit: Will Kirk/JHU
Using a biochemical version of a computer chip, a team led by Johns Hopkins scientists has solved a long-standing mystery correlation to the mating habits of yeast cells.

The findings, described in the Feb. 18 Advance Online Publication of the journal Nature, shed new light on the way cells send and receive signals from one another and from the environment through a process called signal transduction. That process, when impaired, can lead to cancer or other illnesses.

"Yeast is a very simple single-celled organism, but in a number of respects it operates much like a human cell," said Andre Levchenko, an assistant professor in the Department of Biomedical Engineering at Johns Hopkins and supervisor of the research team. "Thats why its been studied for a number of years -- because what we find out in yeast often holds true for humans as well. In this study, we looked at how yeast cells signal one another when they want to merge, engaging in a type of mating behavior. Human cells talk to one another in a similar way, and its important to understand this process".

Yeast cells mate by sending out pheromone designed to catch the attention of nearby cells of the opposite mating type. When a prospective partner picks up this "scent," it alters its shape and sends a projection toward the source of the pheromone, leading to a cellular merger. This mating process is regulated by proteins inside the cell called mitogen-activated protein kinases, or MAPKs, through a chain of chemical reactions.........

Posted by: Kevin      Read more         Source


February 21, 2007, 9:07 PM CT

Lizards 'shout' Against A Noisy Background

Lizards 'shout' Against A Noisy Background Postdoctoral researcher Terry Ord says anole lizards, such as this one, create a strategy to get their message across to rivals. (Courtesy photo)
Lizards that signal to rivals with a visual display "shout" to get their point across, UC Davis researchers have found.

Male anole lizards signal ownership of their territory by sitting up on a tree trunk, bobbing their heads up and down and extending a colorful throat pouch. They can spot a rival lizard up to 25 meters away, said Terry Ord, a postdoctoral researcher at UC Davis who is working with Judy Stamps, professor of evolution and ecology.

The lizards' signals need to be strong enough for a rival to see, but not vivid enough to say "eat me" to a passing predator. But their forest home can be a visually noisy environment, with branches and leaves waving in the breeze and casting patterns of light and shade.

"They have to have a strategy to get their message across," Ord said.

Ord videotaped two species of anole lizards, Anolis cristatellus and Anolis gundlachi, in the Caribbean National Forest in Puerto Rico. He found that the more "visual noise" in the background, the faster and more exaggerated the movements of the lizards.

Anole lizards are interesting to evolutionary biologists because different species are found on different islands all over the Caribbean. The lizards are not particularly closely related -- they are separated by 30 million years of evolution -- but they live in similar environments with the same obstacles to communication. So Ord is using them as a model to investigate the evolution of such signals.........

Posted by: Ashley      Read more         Source


February 21, 2007, 9:03 PM CT

Reduced Brain Growth In Alcoholics

Reduced Brain Growth In Alcoholics
The brains of alcohol-dependent individuals are affected not only by their own heavy drinking, but also by genetic or environmental factors associated with their parents drinking, according to a new study by researchers at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH). Researchers found reduced brain growth among alcohol-dependent individuals with a family history of alcoholism or heavy drinking compared to those with no such family history. Their report has been published online in Biological Psychiatry at http://www.sciencedirect.com/science/journal/00063223 as an article in press.

"This is interesting new information about how biological and environmental factors might interact to affect children of alcoholics," notes George Kunos M.D., Ph.D., Scientific Director, Division of Intramural Clinical and Biological Research, NIAAA.

Many studies have shown that alcohol-dependent men and women have smaller brain volumes than non-alcohol-dependent individuals. It is widely believed that this is due to the toxic effects of ethanol, which causes the alcoholics brain to shrink with aging to a greater extent than the non-alcoholics.

"Our study is the first to demonstrate that brain size among alcohol-dependent individuals with a family history of alcoholism is reduced even before the onset of alcohol dependence," explains first author Jodi Gilman, B.S., a NIAAA research fellow and Ph.D. candidate at Brown University working with senior author Daniel Hommer, M.D., of the NIAAA Laboratory of Clinical and Translational Studies (LCTS) and co-author James Bjork, Ph.D., also of the NIAAA/LCTS.........

Posted by: Sean      Read more         Source


February 21, 2007, 8:59 PM CT

Superbot progress

Superbot progress SuperBot modular robotic units assemble into a circular structure able to roll like a wheel.
Wei-Min Shen of the University of Southern California's Information Sciences Institute recently reported to NASA significant progress in developing "SuperBot," identical modular units that plug into each other to create robots that can stand, crawl, wiggle and even roll. He illustrated his comments with striking video of the system in action, video now posted on line.

Shen's presentation took place at the Space Technology and Applications International Forum 2007 (STAIF) held in Albuquerque, New Mexico.

For the report, he first offered a description of the SuperBot work:

"Superbot consists of Lego-like but autonomous robotic modules that can reconfigure into different systems for different tasks. Examples of configurable systems include rolling tracks or wheels (for efficient travel), spiders or centipedes (for climbing), snakes (for burrowing in ground), long arms (for inspection and repair in space), and devices that can fly in micro-gravity environment.

"Each module is a complete robotic system and has a power supply, micro- controllers, sensors, communication, three degrees of freedom, and six connecting faces (front, back, left, right, up and down) to dynamically connect to other modules.

"This design allows flexible bending, docking, and continuous rotation. A single module can move forward, back, left, right, flip-over, and rotate as a wheel. Modules can communication with each other for totally distributed control and can support arbitrary module reshuffling during their operation.........

Posted by: Kevin      Read more         Source


February 21, 2007, 8:56 PM CT

Air Purifiers That Emit Ozone

Air Purifiers That Emit Ozone
ndoor air purifiers that produce even small quantities of ozone may actually make the air dirtier when used at the same time as household cleaning products, scientists at UC Irvine have discovered.

Ozone emitted by purifiers reacts in the air with unsaturated volatile organic compounds such as limonene - a chemical added to cleaning supplies that gives them a lemon fragrance - to create additional microscopic particles, scientists found. Certain ionic purifiers emit ozone as a byproduct of ionization used for charging airborne particles and electrostatically attracting them to metal electrodes. Ozonolysis purifiers emit ozone at higher levels on purpose with the ostensible goal of oxidizing volatile organic compounds in the air.

This research appeared online this morning in Environmental Science and Technology.

"The public needs to be aware that every air purification approach has its limitation, and ionization air purifiers are no exception," said Sergey Nizkorodov, assistant professor of chemistry at UCI and co-author of the study. "These air purifiers can not only elevate the level of ozone, a formidable air pollutant in itself, but also increase the amount of harmful particulate matter in indoor air".

High levels of airborne particles can aggravate asthma and cardiovascular problems, and have been linked to higher death and lung cancer rates. Excess ozone can damage the lungs, causing chest pain, coughing, shortness of breath and throat irritation.........

Posted by: Tyler      Read more         Source


February 20, 2007, 8:59 PM CT

Our View Of The Gamma-ray Sky

Our View Of The Gamma-ray Sky Artist's impression of Integral
Integral's latest survey of the gamma-ray universe continues to change the way astronomers think of the high-energy cosmos. With over seventy percent of the sky now observed by Integral, astronomers have been able to construct the largest catalogue yet of individual gamma-ray-emitting celestial objects. And there is no end in sight for the discoveries.

Integral is the European Space Agency's latest orbiting gamma-ray observatory. Ever since Integral began scientific operations in 2003, the project team has been devoting a substantial proportion of its observing time to a survey of the gamma-ray universe.

"The gamma-ray sky is notoriously variable and extremely unpredictable," says Anthony Dean, University of Southampton, UK, one of the original proposers of the Integral mission. Hence, the need for Integral's constant vigilance and an accurate catalogue of all gamma-ray sources. With this, astronomers can target individual gamma-ray objects for more detailed, study.

For the past three and a half years, Integral has been collecting survey data. At the end of every year, the data has been turned into a catalogue of sources.

During the first year, it concentrated on the regions close to the centre of our galaxy and found more than 120 sources. During the following year, Integral broadened its reach and found almost 100 more sources.........

Posted by: Brooke      Read more         Source


February 20, 2007, 8:42 PM CT

Ulysses scores a hat-trick

Ulysses scores a hat-trick This artist's impression shows the ESA-NASA Ulysses spacecraft.
Credits: ESA - C. Carreau
ESA-NASA Ulysses mission has marked another high point in its mission. For the third time in a long and highly successful career, Ulysses has reached its maximum south solar latitude of 80 degrees as it flies over the Sun's southern polar cap.

Launched in 1990, the European-built spacecraft visits both polar regions once every 6.2 years as it circles the Sun in an orbit that is almost perpendicular to the ecliptic, the plane in which the Earth and the planets move.

Although originally designed for a mission lasting 5 years, the Ulysses space probe and its suite of 9 scientific experiments are still going strong after more than 16 years in orbit.

Operating the spacecraft has become more demanding over the years, however, as one consequence of the mission's longevity is a decrease in the electrical power available on board. "Ulysses uses a Radioisotope Thermoelectric Generator, or RTG for short, to generate the electricity needed for the spacecraft subsystems and science instruments", said Nigel Angold, ESA's Mission Operations Manager for Ulysses.

The RTG converts the heat produced by radioactive decay of its fuel into electrical power. "As a result of the decay process, the RTG output decreases with time", said Angold. In recent years, this has necessitated sharing the available power among the science instruments in such a way that key instruments are kept on permanently, while others are operated only part of the time.........

Posted by: Brooke      Read more         Source


February 20, 2007, 7:48 PM CT

Test Identifies Lymphoma Patients Likely to Respond

Test Identifies Lymphoma Patients Likely to Respond
Researchers at the Albert Einstein College of Medicine of Yeshiva University have discovered a genetic signature identifying cases of lymphoma that are uniquely susceptible to a newly developed molecular targeted therapy. As a result, physicians organizing clinical trials of the new therapy will be able to enroll patients who'll be most likely to benefit from it.

The research was led by Dr. Ari Melnick, assistant professor of developmental & molecular biology and medicine at Einstein, who also developed the new lymphoma therapy. The study appears in the February 20 issue of the Proceedings of the National Academy of Sciences.

Each year more than 60,000 Americans are diagnosed with B cell lymphomas-tumors of cells of the immune system that include Hodgkin's and non-Hodgkin's lymphomas. B cells are the immune-system cells that make antibodies. Genetic aberrations can cause B cells to multiply uncontrollably, causing B cell lymphomas.

Dr. Melnick's study focused on a gene called BCL6. The protein it codes for is a transcriptional repressor, which means that it can shut off the functioning of genes in B cells and other cells of the immune system and prevent them from being expressed. The BCL6 protein is normally produced only during a specific stage of B cell development and is never made again. But deregulation of BCL6 can cause the protein to be produced when it shouldn't be. The unwelcome presence of the BCL6 protein blocks the expression of important genes that normally protect cells from becoming cancerous. As a result, malignant B-cell lymphomas occur.........

Posted by: Sean      Read more         Source

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