August 20, 2006, 3:02 PM CT

Regional Storage Facilities Could Handle Nuclear Waste

The Bush administration is eagerly pushing nuclear power as a way to help solve the U.S. energy crisis. But in its new plan for nuclear waste management, the administration is taking the wrong approach, says an MIT professor who studies the nuclear energy industry.

"My hope is that over time, the administration will rethink its priorities in this area," says Richard Lester, professor of nuclear engineering and director of the Industrial Performance Center.

In a recent article published in Issues in Science and Technology, Lester argued that the Bush administration's plan, known as GNEP (Global Nuclear Energy Partnership), is not the best way to encourage further development of nuclear energy.

GNEP, which President Bush announced earlier this year, is meant to stimulate the nuclear industry by coming up with better ways to manage spent nuclear fuel. The plan focuses on reprocessing spent fuel, but Lester believes the administration should focus on finding regional storage facilities for the nuclear waste.

Right now, uncertainty over how to deal with spent fuel, which remains radioactive for hundreds of thousands of years, is one of the major obstacles to the construction of new plants. Thousands of spent fuel rods are now stored in secure pools or concrete casks located near nuclear plants, which is not considered a long-term solution.........

Posted by: Ethen      Permalink         Source

August 19, 2006, 9:14 PM CT

Stellar Pinwheels At Our Galaxy's Core

Astronomers have finally learned the identity of a mysterious "Quintuplet Cluster" of stars situated near the supermassive black hole at our galaxy's core: At least two of the objects are not individual stars, but binary pairs that live fast and die young, forming fiery pinwheels as they spin around one another.

A multinational team led by Peter Tuthill of the University of Sydney in Australia, used the extraordinary resolution of the 10-meter telescope at the W.M. Keck Observatory in Hawaii, to determine the nature of the enigmatic objects. They report their findings in the Aug. 18 issue of the journal Science.

Until these observations, scientists had not known whether the extremely red "cocoon" quintuplets were aging stars surrounded by shells of dust, or young stars accompanied by disks of bright gas. Neither hypothesis was convincing, and neither fully explained the enormous light output: Each quintuplet emits 10,000 to 100,000 times as much radiation as the Sun.

The new findings indicate the quintuplets are members of a rare class called "Wolf-Rayet colliding-wind binaries" -- massive, fast-burning star pairs that live only a few million years before exploding in terminal supernovae. By contrast, the Sun is about 5 billion years old and only middle-aged. The pinwheel effect is caused by the way each star's dusty mantle is affected by that of its partner, producing spiral plumes.........

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August 19, 2006, 9:08 PM CT

Loss Of Just One Species Makes Big Difference

Researchers at Dartmouth, Cornell University, and the University of Wyoming have learned that the removal of just one important species in a freshwater ecosystem can seriously disrupt how that environment functions. This finding contradicts earlier notions that other species can jump in and compensate for the loss.

Brad Taylor, currently a research associate in the department of biological sciences at Dartmouth, and his colleagues studied a fish called the flannelmouth characin (Prochilodus mariae) native to South American rivers. This particular fish eats detritus, the fine organic matter on the river bottom, and because of this, it plays a critical role in regulating the breakdown and transport of carbon in the rivers.

"This fish species is a popular food source; it is harvested regularly, and in some cases, it's overfished," says Taylor, the lead author on the study that was published in the August 11 issue of the journal Science. "We learned that removing this particular fish greatly altered the metabolic activity of the river ecosystem. Other fish species did not compensate for the lack of Prochilodus, an effect consistent with observations from other rivers where they have been excluded much longer by dams".

The researchers used a heavy, plastic divider to split a 210-meter stretch (a little more than a tenth of a mile) of Rio Las Marías in Venezuela into two separate river sections. On one side, they removed only Prochilodus, and on the other, all the fish remained. The team then took a series of measurements upstream and downstream to quantify the transport of particulate organic carbon (POC).........

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August 19, 2006, 8:50 AM CT

New Species Of Sea Urchin For Acution At Ebay

You can get almost anything at eBay. Now it seems you can even discover a new marine species at ebay.

Sea Urchins are a member of the Phylum Echinodermata, Class Echinoidea. Rather then having arms or legs the sea urchin actually has long spines as a substitute. These spines are used primarily for camouflage, locomotion, and defensive purposes. The sea urchin feeds on sea grasses, algae, and decaying organic matter. One can see their close relationship to the sand dollar and starfish by looking closely at their underside, near the middle, where the familiar 5 pointed star pattern can be found. Its body is enclosed in a rigid shell, or test, made up of ten double rows of immovable plates firmly joined in a regular pattern. Sea urchins reproduce sexually by discharging either eggs or sperm into the sea, where the eggs are fertilized. This animal, which feeds primarily on vegetation and small organisms, can easily repair damage to its shell, spines, tube feet, and pedicellarieae by regenerating new parts. Sea urchins live on undersea rocks, ledges, boulders, or coral reefs.........

Posted by: Beverly      Permalink         Source

August 18, 2006, 6:24 AM CT

How Light Pushes Atoms

A research paper would be published in the 18 August edition of the journal Physical Review Letters reveals a new effect in the fundamental way that laser light interacts with atoms. "Unlike water, which speeds up as it passes through a small nozzle, photons of light have less momentum at the center of a focused laser beam," says Kurt Gibble, an associate professor of physics at Penn State University and the author of the research paper. Gibble's theoretical paper analyzes the speed of an atom after it absorbs a photon of light and reveals the surprising effect that a photon in a narrow laser beam delivers less momentum to an atom than does a photon in a wide beam of light.

Einstein proposed that a light wave is made of photons that carry discrete packets of energy. "When a photon hits an atom, the atom recoils with a speed that is determined by the photon's momentum, similar to two balls colliding on a billiard table," Gibble explains. Physicists often think of a focused laser beam as the intense intersection of two or more infinitely wide light waves, and Gibble's discovery provides an important new understanding of what happens to an atom that is pummeled by photons coming from the different directions of these multiple intersecting light waves. "You might think that an atom would absorb a photon randomly from only one of the beams, but this paper shows that the atom feels the effect of the photons from all of the beams simultaneously and, surprisingly, that it recoils with a speed that is less than it would get from the momentum of any one of the infinitely wide photons".........

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August 14, 2006, 11:56 PM CT

Bacteria Can Help Predict Ocean Change

Every creature has its place and role in the oceans even the smallest microbe, as per a new study that may lead to more accurate models of ocean change.

Researchers have long endorsed the concept of a unique biological niche for most animals and plants a shark, for example, has a different role than a dolphin.

Bacteria instead have been relegated to an also-ran world of "functional redundancy" in which few species are considered unique, said Jed Fuhrman, holder of the McCulloch-Crosby Chair in Marine Biology in the USC College of Letters, Arts and Sciences.

In The Proceedings of the National Academy of Sciences' Early Edition, Fuhrman and his colleagues from USC and Columbia University show that most kinds of bacteria are not interchangeable and that each thrives under predictable conditions and at predictable times.

On the other hand, the kinds and numbers of bacteria in a sample can show where and when it was taken.

"I could tell you what month it is if you just got me a sample of water from out there," Fuhrman said.

The scientists took monthly bacteria samples for more than four years in the Pacific Ocean near the USC Wrigley Institute's marine laboratory on Catalina Island.

They used statistical methods to correlate the bacteria counts with the Wrigley Institute's monthly measurements of water temperature, salinity, nutrient content, plant matter and other variables.........

Posted by: Beverly      Permalink         Source

August 14, 2006, 11:52 PM CT

Surprising Telescope Observations

A heavy form of hydrogen created just moments after the Big Bang has been found to exist in larger quantities than expected in the Milky Way, a finding that could radically alter theories about star and galaxy formation, says a new international study led by the University of Colorado at Boulder.

CU-Boulder astrophysicist Jeffrey Linsky said new data gathered by NASA's Far Ultraviolet Spectroscopic Explorer, or FUSE, satellite, shows why deuterium appears to be distributed unevenly in the Milky Way Galaxy. It apparently has been binding to interstellar dust grains, changing from an easily detectable gaseous form to an unobservable solid form, said Linsky, a fellow of JILA, a joint institute of CU-Boulder and the National Institute of Standards and Technology.

The FUSE deuterium study, six years in the making, solves a 35-year-old mystery concerning the distribution of deuterium in the Milky Way while posing new questions about how stars and galaxies are made, according to the research team. A paper on the subject by a team of international researchers led by Linsky is being published in the Aug. 20 issue of The Astrophysical Journal.

"Since the 1970s, we have been unable to explain why deuterium levels vary all over the place," said Linsky. "The answer we found is as unsettling as it is exciting".........

Posted by: Beverly      Permalink         Source

August 14, 2006, 11:43 PM CT

High-Fat Copper-Rich Diets

Among elderly adults whose diets are high in saturated and trans fats, a high intake of copper may be linked to an accelerated rate of decline in thinking, learning and memory abilities, as per a report in the recent issue of Archives of Neurology, one of the JAMA/Archives journals.

Eventhough copper, zinc and iron are essential for brain development and function, an imbalance of these metals may play a role in the development of brain plaques linked to Alzheimer's disease. Prior studies have also linked fat intake, particularly that of saturated and trans fats, to Alzheimer's disease and other forms of cognitive difficulties, as per background information in the article. One recent animal study observed that the consumption of copper in drinking water could amplify the degenerative effects of a high-fat diet on rabbit brains.

Martha Clare Morris, Sc.D., associated professor at the Institute for Healthy Aging at Rush University Medical Center, and her colleagues assessed the correlation between dietary fat and dietary copper intake in 3,718 Chicago residents age 65 years and older. Participants underwent cognitive testing at the beginning of the study, after three years and after six years. An average of one year after the study began, they filled out a questionnaire about their diets. The dietary recommended allowance of copper for adults is.9 milligrams per day. Organ meats, such as liver, and shellfish are the foods with the highest copper levels, followed by nuts, seeds, legumes, whole grains, potatoes, chocolate and some fruits. Copper pipes may also add trace amounts of the metal to drinking water.........

Posted by: Ethen      Permalink         Source

August 12, 2006, 3:27 PM CT

Sharpest Manmade Thing

A field ion microscope (FIM) image of a very sharp tungsten needle. The small round features are individual atoms. The lighter colored elongated features are traces captured as atoms moved during the imaging process (approximately 1 second).

Reported by: Rezeq et al., Journal of Chemical Physics, 28 May 2006.........

Posted by: Beverly      Permalink         Source

August 12, 2006, 3:11 PM CT

Fish Eating Fish

Two fish for the price of one!

Some lucky one can have both.........

Posted by: Ethen      Permalink         Source

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