February 26, 2007, 7:05 PM CT

South Pole Telescope To Help Scientists

Just days before nations around the world were set to begin a coordinated global research campaign called the International Polar Year (IPY); scientists at the South Pole aimed a massive new telescope at Jupiter and successfully collected the instrument's first test observations.

Soon, a far more distant quarry will enter the South Pole telescope's (SPT) sights, as a team of researchers from nine institutions tackles fundamental mysteries of modern cosmology and the nature of the universe: What, for example, is dark energy, the force that dominates the universe?

The $19.2 million telescope is funded primarily by the National Science Foundation (NSF), with additional support from the Kavli Foundation of Oxnard, Calif., and the Gordon and Betty Moore Foundation of San Francisco.

"The telescope, camera and optics are all working as designed," said John Carlstrom, the S. Chandrasekhar distinguished service professor in astronomy and astrophysics at the University of Chicago, who heads the SPT team that tested the scope on Feb. 26. "SPT's first light is a major milestone for the project and a fitting conclusion to a remarkably productive summer at the South Pole station. We now look forward to fully characterizing the instrument and beginning cosmological observations"......... Posted by: Beverly      Read more         Source

February 26, 2007, 6:22 PM CT

The cost of keeping eggs fresh for mother cockroaches

One of the defining differences between the sexes is in the size of their gametes. Males make many tiny sperm while females make only a few large eggs. This suggests that sperm are cheap while eggs are expensive. Yet sperm can be very long lived, while eggs degenerate quickly after they are made if they are not fertilized. Why don't females take better care of their expensive eggs? After all, if the females don't use their eggs they have fewer offspring, whereas males make more sperm then they will use anyway. This evolutionary conundrum there should be selection for females to keep their eggs fresh until they are used has recently been studied by Dr. Trish Moore and her colleagues at the Cornwall Campus of the University of Exeter, with support from NERC, and is published in the recent issue of The American Naturalist.

Moore and colleagues examined why females don't keep their eggs fresh in a cockroach where females mate only once during a reproductive cycle, give live birth, and therefore are choosy about the male with which they will mate. Females can't be too choosy, however. If they wait too long to mate they lose good quality oocytes through programmed cell death. But Moore's team finds that some females have genes that would allow them to maintain eggs even if they delay mating. So why aren't all females delaying cell death and holding onto their eggs? Moore speculates that perhaps these genes play a dual role and while they may be beneficial under one environment, when females don't mate, they might be harmful under another, such as when food is limiting. "When females are starving, hanging on to yolky eggs full of nutrients is bad. Instead a female could recycle those nutrients into her survival. So females face a decision between keeping eggs fresh for producing offspring now, or using those nutrients herself and taking the chance she can reproduce later." The group is currently investigating this trade-off arising from a conflict over food or sex. Although this is a new twist in the conflict over food or sex, the result is a familiar one in evolutionary biology; it is hard to be best at everything......... Posted by: Beverly      Read more         Source

February 22, 2007, 10:15 PM CT

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: Beverly      Read more         Source

February 21, 2007, 9:42 PM CT

Influenza Virus Genomes Now Accessible

The Influenza Genome Sequencing Project, funded by the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health (NIH), announced recently that it has achieved a major milestone. The entire genetic blueprints of more than 2,000 human and avian influenza viruses taken from samples around the world have been completed and the sequence data made available in a public database.

"This information will help scientists understand how influenza viruses evolve and spread," says NIH Director Elias A. Zerhouni, M.D., "and it will aid in the development of new flu vaccines, therapies and diagnostics".

"Scientists around the world can use the sequence data to compare different strains of the virus, identify the genetic factors that determine their virulence, and look for new therapeutic, vaccine and diagnostic targets," says NIAID Director Anthony S. Fauci, M.D.

The Influenza Genome Sequencing Project, initiated in 2004, has been carried out at the NIAID-funded Microbial Sequencing Center managed by The Institute for Genomic Research (TIGR) of Rockville, Maryland. The project is currently directed by David Spiro, Ph.D., and Claire Fraser, Ph.D., at TIGR and Elodie Ghedin, Ph.D., at the University of Pittsburgh School of Medicine. Recently, growing sequencing capacity has enabled the production rate to increase to more than 200 viral genomes per month. Eclipsing todays milestone of 2,000 genomes, the microbial sequencing center will continue to rapidly sequence more influenza strains and isolates and will make all the sequence data freely available to the scientific community and the public through GenBank, an Internet-accessible database of genetic sequences maintained by the National Center for Biotechnology Information (NCBI) at NIHs National Library of Medicine, another major contributor to the project......... Posted by: Beverly      Read more         Source

February 21, 2007, 9:23 PM CT

Creates Metallic Interconnects, Nanostructures

reating high-resolution metallic interconnects is an essential part of the fabrication of microchips and other nanoscale devices. Researchers at the University of Illinois at Urbana-Champaign have developed a simple and robust electrochemical process for the direct patterning of metallic interconnects and other nanostructures.

"Solid-state superionic stamping offers a new approach, both as a stand-alone process and as a complement to other nanofabrication techniques, for creating chemical sensors, photonic structures and electrical interconnects," said Nicholas X. Fang, a professor of mechanical science and engineering, and corresponding author of a paper published in the Feb. 14 issue of the journal Nano Letters.

The S4 process uses a patterned superionic material as a stamp, and etches a metallic film by an electrochemical reaction. In superionic materials, metal ions can move almost freely around the crystal lattice. These mobile materials can also be used in batteries and fuel cells.

Unlike conventional processing in which patterns are first placed on photoresist, followed by metal deposition and subsequent etching the S4 process creates.

high-resolution metallic nanopatterns in a single step, potentially reducing manufacturing costs and increasing yields......... Posted by: Beverly      Read more         Source

February 21, 2007, 9:13 PM CT

Watching Sky Through Three Giant Eyes

The ESO Very Large Telescope Interferometer, which allows astronomers to scrutinise objects with a precision equivalent to that of a 130-m telescope, is proving itself an unequalled success every day. One of the latest instruments installed, AMBER, has led to a flurry of scientific results, an anthology of which is being published this week as special features in the research journal Astronomy & Astrophysics.

"With its unique capabilities, the VLT Interferometer (VLTI) has created itself a niche in which it provide answers to a number of astronomical questions, from the shape of stars, to discs around stars, to the surroundings of the supermassive black holes in active galaxies," says Jorge Melnick (ESO), the VLT Project Scientist. The VLTI has led to 55 scientific papers already and is in fact producing more than half of the interferometric results worldwide.

"With the capability of AMBER to combine up to three of the 8.2-m VLT Unit Telescopes, we can really achieve what nobody else can do," added Fabien Malbet, from the LAOG (France) and the AMBER Project Scientist.

Eleven articles will appear this week in Astronomy & Astrophysics' special AMBER section. Three of them describe the unique instrument, while the other eight reveal completely new results about the early and late stages in the life of stars......... Posted by: Beverly      Read more         Source

February 21, 2007, 9:10 PM CT

Bacteria to steady buildings against earthquakes

Soil bacteria could be used to help steady buildings against earthquakes, according to researchers at UC Davis. The microbes can literally convert loose, sandy soil into rock.

When a major earthquake strikes, deep, sandy soils can turn to liquid, with disastrous consequences for buildings sitting on them. Currently, civil engineers can inject chemicals into the soil to bind loose grains together. But these epoxy chemicals may have toxic effects on soil and water, said Jason DeJong, an assistant professor of civil and environmental engineering at UC Davis.

The new process, so far tested only at a laboratory scale, takes advantage of a natural soil bacterium, Bacillus pasteurii. The microbe causes calcite (calcium carbonate) to be deposited around sand grains, cementing them together. By injecting bacterial cultures, additional nutrients and oxygen, DeJong and his colleagues found that they could turn loose, liquefiable sand into a solid cylinder.

"Starting from a sand pile, you turn it back into sandstone," DeJong said. Similar techniques have been used on a smaller scale, for example, to repair cracks in statues, but not to reinforce soil.

The new method has several advantages, DeJong said. There are no toxicity problems, compared with chemical methods. The treatment could be done after construction or on an existing building, and the structure of the soil is not changed -- some of the void spaces between grains are just filled in......... Posted by: Beverly      Read more         Source

February 19, 2007, 7:47 PM CT

Clues to 'Constant' Change

ears of comparisons among the world's best atomic clocks-based on different atoms-have established the most precise limits ever achieved in the laboratory for detecting possible changes in so-called "constants" of nature. The comparisons at the National Institute of Standards and Technology (NIST) may help researchers test the latest theories in physics and develop a more complete understanding of the history of the universe.

Some astronomical and geological studies suggest there might have been very small changes in the values of fundamental constants over billions of years, eventhough the results have been inconsistent and controversial. If fundamental constants are changing, the present-day rates of change are too small to be measured using conventional methods. However, a new comparison of NIST's cesium fountain and mercury ion clocks, scheduled to appear in this week's issue of Physical Review Letters,* has narrowed the range in which one of them-the "fine-structure constant"- possibly could be changing by a factor of 20. Widely used in physical theory and experiments, the fine-structure constant, represents the strength of the interaction between electrons and photons.

Astronomers and geologists have attempted to detect changes in natural constants by examining phenomena dating back billions of years. The NIST experiments attained the same level of precision by comparing the relative drifts in the "ticks" of an experimental mercury ion clock, which operates at optical frequencies, and NIST-F1, the national standard cesium clock, which operates at lower microwave frequencies. These data can be plugged into equations to obtain upper limits for possible rates of change of the fine structure constant in recent times......... Posted by: Beverly      Read more         Source

February 19, 2007, 7:09 PM CT

Recast Usual View of Elusive Force

Physicists at JILA have demonstrated that the warmer a surface is, the stronger its subtle ability to attract nearby atoms, a finding that could affect the design of devices that rely on small-scale interactions, such as atom chips, nanomachines, and microelectromechanical systems (MEMS).

The research highlights an underappreciated aspect of the elusive Casimir-Polder force, one of the stranger effects of quantum mechanics. The force arises from the ever-present random fluctuation of microscopic electric fields in empty space. The fluctuations get stronger near a surface, and an isolated neutral atom nearby will feel them as a subtle pull-a flimsy, invisible rubber band between bulk objects and atoms that may be a source of friction, for example, in tiny devices. The JILA group previously made the most precise measurement ever of Casimir-Polder, measuring forces hundreds of times weaker than ever before and at greater distances (more than 5 micrometers). JILA is a joint institute of the National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder.

Now, as reported in last week's Physical Review Letters*, the JILA team has made the first measurement of the temperature dependence of this force. By using a combination of temperatures at opposite extremes-making a glass surface very hot while keeping the environment neutral and using ultracold atoms as a measurement tool-the new research underscores the power of surfaces to influence the Casimir-Polder force. That is, electric fields within the glass mostly reflect inside the surface but also leak out a little bit to greatly strengthen the fluctuations in neighboring space. As a result, says group leader and NIST Fellow Eric Cornell, "warm glass is stickier than cold glass"......... Posted by: Beverly      Read more         Source

February 15, 2007, 6:24 AM CT

Grizzly Bears Feast On Diverse Diet

Theres no such thing as picky grizzly bearstheyll eat almost anything they can find. A new University of Alberta study that tracked food habits of the Alberta grizzly bear living in the foothills sheds some light on the animals varied diet and their activity pattern.

Alberta bears have remarkably diverse diets, said Dr. Mark Boyce, biological sciences professor at the U of A and co-author on the study. Theyll eat just about anything.

Ants, fruits, moose and plants are a few staples of the Alberta grizzly bears diet. This new research study was the most comprehensive examination of grizzly bear foods ever conducted in Canada. Using global positioning system (GPS) radiotelemetry technology and analyzing 665 feces collected from 18 grizzly bears over a period of three years, the scientists found that the bears packed a lot of activity into 24 hours. The research was recently published in the Journal of Mammalogy.

Much is known about what bears in mountainous areas eat but little is known of the diets of grizzly bears living in boreal forests also used by humans. As well, this new research looked at five different activities the bears use to find foodwhether it feeds on flowers, insects, fruits, digs for plants or kills other animals, specifically ungulates......... Posted by: Beverly      Read more         Source