October 15, 2006, 8:31 PM CT

Marine Life Stirs Ocean

Oceanographers worldwide pay close attention to phytoplankton and with good reason. The microscopic plants that form the vast foundation of the marine food chain generate a staggering amount of power, and now a groundbreaking study led by Florida State University has calculated just how much -- about five times the annual total power consumption of the human world.

Physical and biological oceanographers led by FSU Professor William Dewar put the yearly amount of chemical power stored by phytoplankton in the form of new organic matter at roughly 63 terawatts, and that's a lot of juice: Just one terawatt equals a trillion watts. In 2001, humans collectively consumed a comparatively measly 13.5 terawatts.

What's more, their study found that the marine biosphere -- the chain of sea life anchored by phytoplankton -- invests around one percent (1 terawatt) of its chemical power fortune in mechanical energy, which is manifested in the swimming motions of hungry ocean swimmers ranging from whales and fish to shrimp and krill. Those swimming motions mix the water much as cream is stirred into coffee by swiping a spoon through it.

And the sum of all that phytoplankton-fueled stirring may equal climate control.

"By interpreting existing data in a different way, we have predicted theoretically that the amount of mixing caused by ocean swimmers is comparable to the deep ocean mixing caused by the wind blowing on the ocean surface and the effects of the tides," Dewar said.........

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October 15, 2006, 8:17 PM CT

Giant Pandas Can See Color

They may be black and white, but new research at the Georgia Institute of Technology and Zoo Atlanta shows that giant pandas can see in color. Graduate researcher Angela Kelling tested the ability of two Zoo Atlanta pandas, Yang Yang and Lun Lun, to see color and found that both pandas were able to discriminate between colors and various shades of gray. The research is published in the psychology journal Learning and Behavior, volume 34 issue 2.

"My study shows that giant pandas have some sort of color vision," said Kelling, graduate student in Georgia Tech's Center for Conservation Behavior in the School of Psychology. "Most likely, their vision is dichromatic, since that seems to be the trend for carnivores".

Vision is not a well-studied aspect of bears, including the giant pandas. It has long been thought that bears have poor vision, perhaps, Kelling said, because they have such excellent senses of smell and hearing. Some experts have thought that bears must have some sort of color vision as it would help them in identifying edible plants from the inedible ones, although there's been little experimental evidence of this. However, one experiment on black bears found some evidence that bears could tell blue from gray and green from gray. Kelling used this study's design as the basis to test color vision in Zoo Atlanta's giant pandas.........

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October 15, 2006, 8:11 PM CT

Bistable Nanoswitch

Carbon nanotubes (CNT) have been under intense study by researchers all over the world for more than a decade and are being thought of as ideal building blocks for nanoelectromechanical systems (NEMS). A type of one-dimensional structure with high-aspect ratio, carbon nanotubes have emerged as a promising material because of their a number of impressive mechanical, electrical and chemical properties.

Now researchers from Northwestern University have demonstrated a novel carbon nanotube-based nanoelectromechanical switch exhibiting bistability based on current tunneling. The device could help advance technological developments in memory chips and electronic sensing devices.

The research is published online by the scientific journal Small.

"We believe the unique characteristics of this nano device will likely lead to a number of high-impact applications in the field of nanoelectronics and nanosensors," said Horacio Espinosa, professor of mechanical engineering in the McCormick School of Engineering and Applied Science. Espinosa and Changhong Ke, a former graduate student of Espinosa's, co-authored the paper.

Since the invention of the integrated circuit (IC), the semiconductor industry has boomed following the famous Moore's law. However, as the characteristic dimension achievable by various photolithography techniques approaches its physical limits, researchers are searching for new materials and new device concepts to be able to continue the large-scale integration trend.........

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October 15, 2006, 7:16 PM CT

Same Gene For Cleft Lip And Skin Biology

Following up on an earlier discovery that a gene called IRF6 is involved in the common birth defect cleft lip and palate, researchers at the University of Iowa Roy J. and Lucille A. Carver College of Medicine and their colleagues have identified the function of the gene. Their latest findings, published online Oct. 15 in Nature Genetics, reveal an unexpected role for IRF6 in the growth and development of skin cells, a discovery that may have implications for wound healing and cancer research.

In 2002, Brian Schutte, Ph.D., UI associate professor of pediatrics and nursing, and Jeff Murray, M.D., UI professor of pediatrics, pediatric dentistry and biological sciences, and the Roy J. Carver Chair in Perinatal Health, led a study showing that mutations in IRF6 cause Van der Woude syndrome (VWS), a rare, dominantly inherited form of cleft lip and palate. Subsequently, the researchers found that this gene also is mutated in 10 to 15 percent of the more common, so-called non-syndromic cases of cleft lip and palate. Cleft lip and palate, where the lip or both the lip and palate (roof of the mouth) fail to close, occurs in approximately one of every 1,000 babies.

In order to determine the function of this gene, the researchers created mice that lacked IRF6. These mice had very abnormal skin as well as a cleft palate. Detailed analysis of the mice revealed that IRF6 regulates the proliferation and differentiation of keratinocytes -- the main cell type in the epidermis or outer layer of skin. Keratinocytes also provide a protective barrier around the mouth, gut, liver, lung, kidney and other internal organs.........

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October 15, 2006, 7:03 PM CT

Friendly Bacteria To Fight Food Allergies

Feeding babies alcoholic milk may help to protect against some food allergies. Kefir, a traditional fermented drink, is consumed in Eastern Europe as a health food, and is often used to wean babies, as it is easily digested. Food allergy prevalence is especially high in children under the age of three, with around 5-8% of infants at risk. Currently the only treatment is avoidance of the problematic food.

"Friendly" bacteria in kefir may play a role in blocking the pathway involved in allergic responses, Lisa Richards reports in Chemistry & Industry, SCI's fortnightly magazine. Research published recently [Monday 16 October 2006(DOI 10.1002/jsfa2469)] in the SCI's Journal of the Science of Food and Agriculture has shown that the milk drink inhibits the allergen specific antibody Immunoglobulin E (IgE). IgE is involved in immune responses to inactivate organisms that might cause disease. However, in the presence of allergens it can also activate cells responsible for the release of histamine, a chemical which stimulates allergic responses, such as inflammation and constriction of airways.

Ji-Ruei Liu's team of scientists at the National Formosa University, Yunlin, Taiwan, fed mice the milky drink, and found that after 3 weeks, the amount of ovalbumin (OVA) specific IgE was reduced three-fold. Ovalbumin is an allergenic protein found in egg whites, which cause most allergies in young children. Kefir is also reported to prevent food antigens from passing through the intestinal wall.........

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October 15, 2006, 6:55 PM CT

Reward Perception In Cocaine Addiction

People addicted to cocaine have an impaired ability to perceive rewards and exercise control due to disruptions in the brain's reward and control circuits, as per a series of brain-mapping studies and neuropsychological tests conducted at the U.S. Department of Energy's Brookhaven National Laboratory.

"Our findings provide the first evidence that the brain's threshold for responding to monetary rewards is modified in drug-addicted people, and is directly associated with changes in the responsiveness of the prefrontal cortex, a part of the brain essential for monitoring and controlling behavior," said Rita Goldstein, a psychology expert at Brookhaven Lab. "These results also attest to the benefit of using sophisticated brain-imaging tools combined with sensitive behavioral, cognitive, and emotional probes to optimize the study of drug addiction, a psychopathology that these tools have helped to identify as a disorder of the brain".

Goldstein will present details of these studies at a press conference on neuroscience and addiction at the Society for Neuroscience (SfN) annual meeting in Atlanta, Georgia, on Sunday, October 15, 2006, 2 to 3 p.m., and at a SfN symposium on Wednesday, October 18, 8:30 a.m.*.

Goldstein's experiments were designed to test a theoretical model, called the Impaired Response Inhibition and Salience Attribution (I-RISA) model, which postulates that drug-addicted individuals disproportionately attribute salience, or value, to their drug of choice at the expense of other potentially but no-longer-rewarding stimuli -- with a concomitant decrease in the ability to inhibit maladaptive drug use. In the experiments, the researchers subjected cocaine-addicted and non-drug-addicted individuals to a range of tests of behavior, cognition/thought, and emotion, while simultaneously monitoring their brain activity using functional magnetic resonance imaging (fMRI) and/or recordings of event-related potentials (ERP).........

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October 12, 2006, 9:56 PM CT

Northern Bogs Andt Global Warming

Methane gas released by peat bogs in the northern-most third of the globe probably helped fuel the last major round of global warming, which drew the ice age to a close between 11,000 and 12,000 years ago, UCLA and Russian Academy of Sciences scientists have concluded.

But the new information in no way lets human sources of greenhouse gases off the hook for the present round of global warming, warn the team of researchers whose findings are published in the Oct. 13 issue of Science.

"If anything, our findings show just how sensitive the planet's environment is to change and just how complex the results of these changes may be," said Glen M. MacDonald, the lead author of the study and a UCLA climate change scholar.

As the incipient bogs were strong producers of methane, the findings help solve a long-standing mystery about the source of a massive infusion of atmospheric methane that helped raise the Earth's surface temperature following the ice age.

"Scientists have long known that the northern bogs produce methane, but until now they were generally dismissed as the source of this change at the close of the last ice age because they were thought to have formed too slowly and too late to be a factor," said Laurence C. Smith, a UCLA professor of geography and study coauthor. "The initial development of the huge complex of northern bogs that now cover 1.54 million square miles occurred earlier than previously thought." .........

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October 12, 2006, 9:06 PM CT

Health of Florida's Coral Reef

NASA satellite data was used to help monitor the health of Florida's coral reef as part of a field research effort completed this August and September.

The project was the first comprehensive assessment of the resiliency of reefs along the National Oceanic and Atmospheric Administration's (NOAA) Florida Keys National Marine Sanctuary. The sanctuary is administered by NOAA in partnership with the Florida Department of Environmental Protection. The Sanctuary stretches from the Dry Tortugas to the southern boundary of Biscayne National Park. The area north of there has reefs and is part of the Florida Reef Resilience Program, but lies outside the sanctuary. Scientists are trying to determine why some reefs are resilient to environmental changes and impacts. The work may also identify ways to care for reefs worldwide.

At nearly 175 sites, scuba divers recorded the number and species of coral and the extent of bleaching -- corals turn white when tiny algae that live inside them die. Bleaching is a symptom of coral stress, which can be caused by high water temperatures, other environmental stresses, or disease. The project was part of the Florida Reef Resiliency Program, funded by the state of Florida and The Nature Conservancy. It involved volunteers and researchers from several agencies, organizations and universities, including the University of South Florida.........

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October 12, 2006, 7:56 PM CT

Plants Become Air Quality Detectives

What does a garden have to do with the chemistry of the atmosphere and air quality? One of the newest exhibits at NASA Goddard's Visitor Center, Greenbelt, Md., is a project correlation to NASA's Aura satellite. Aura is currently studying atmospheric chemistry and air pollution from space. The new Aura Ozone Monitoring Garden is used to study air quality from the ground by seeing how ozone in the air damages the leaves of certain plants.

During the summer months of intense sunlight, the air surrounding major urban areas undergoes dramatic changes. Ozone is formed when chemical pollutants that are by-products of human activities such as biomass burning and the combustion of fossil fuels react in the presence of sunlight. Ozone is a molecule that at ground level is a harmful air pollutant in high or prolonged concentrations.

Ozone tolerance among plants and people varies. As per research at the Great Smoky Mountain National Park and elsewhere, a number of common species of plants are sensitive to high concentrations of ozone. The Aura Ozone Monitoring Garden features plants that are known to be ozone sensitive, such as white dogwood (Cornus florida) and cardinal flower (Lobelia cardinalis).

A number of of the plants that have been found to be ozone sensitive thrive in a wide range of the temperate environments within the continental United States. Aura education personnel at Goddard chose a variety of plants for the garden that represent different growing environments, from agriculture to horticulture.........

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October 12, 2006, 7:49 PM CT

Jupiter's Little Red Spot Growing

The highest wind speeds in Jupiter's Little Red Spot have increased and are now equal to those in its older and larger sibling, the Great Red Spot, according to observations with NASA's Hubble Space Telescope.

The Little Red Spot's winds, now raging up to approximately 400 miles per hour, signal that the storm is growing stronger, according to the NASA-led team that made the Hubble observations. The increased intensity of the storm probably caused it to change color from its original white in late 2005, according to the team.

"No one has ever seen a storm on Jupiter grow stronger and turn red before," said Amy Simon-Miller of NASA's Goddard Space Flight Center, Greenbelt, Md., lead author of a paper describing the new observations appearing in the journal Icarus. "We hope continued observations of the Little Red Spot will shed light on the many mysteries of the Great Red Spot, including the composition of its clouds and the chemistry that gives it its red color".

Although it seems small when viewed against Jupiter's vast scale, the Little Red Spot is actually about the size of Earth, and the Great Red Spot is around three Earth diameters across. Both are giant storms in Jupiter's southern hemisphere powered by warm air rising in their centers.

The Little Red Spot is the only survivor among three white-colored storms that merged together. In the 1940s, the three storms were seen forming in a band slightly below the Great Red Spot. In 1998, two of the storms merged into one, which then merged with the third storm in 2000. In 2005, amateur astronomers noticed that this remaining, larger storm was changing color, and it became known as the Little Red Spot after becoming noticeably red in early 2006.........

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