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December 13, 2006, 6:42 PM CT

When You Grow Up In Bad Neighborhood

When You Grow Up In Bad Neighborhood
There's good news for children growing up in bad neighborhoods in a comprehensive study led by nationally renowned University of Colorado at Boulder sociology Professor Delbert Elliott.

The 8-year effort analyzing the successful development of children in different kinds of neighborhoods in Denver and Chicago found that children growing up in high-poverty neighborhoods were doing much better than expected. The rate of successful development for children from the best neighborhoods was 63 percent while the success rate for children living in high-poverty, disadvantaged neighborhoods was 52 percent.

"There's an 11-point difference between our worst neighborhoods and our best neighborhoods," said Elliott, director of the CU-Boulder Center for the Study and Prevention of Violence. "That's very surprising".

"The idea that living in high-poverty, disorganized, disadvantaged neighborhoods is kind of a death sentence for kids is clearly not the case," he said. "We're getting kids coming out of those neighborhoods that are doing quite well".

The examination of neighborhoods was one of four integrated studies launched by the John D. and Catherine T. MacArthur Foundation's Network on Successful Adolescent Development. The portion of the study conducted by Elliott and his colleagues looked at neighborhoods, while three other teams focused on family and school influences on development, and youth development in rural farming areas.........

Posted by: John      Permalink         Source

December 13, 2006, 5:04 AM CT

Squid-inspired Design For Underwater Vehicles

Squid-inspired Design For Underwater Vehicles Numerical simulations and the computational mesh around RAV
Credit: Image courtesy CU-Boulde
Inspired by the sleek and efficient propulsion of squid, jellyfish and other cephalopods, a University of Colorado at Boulder researcher has designed a new generation of compact vortex generators that could make it easier for researchers to maneuver and dock underwater vehicles at low speeds and with greater precision.

In addition, the technology - seemingly inspired by the plots of two classic sci-fi films - may soon allow doctors to guide tiny capsules with jet thrusters through the human digestive tract, enabling them to diagnose disease and dispense medications.

Kamran Mohseni, an assistant professor of aerospace engineering sciences, will present these and other details at the American Geophysical Union's annual fall meeting Dec. 11-15 in San Francisco. A global network of scientists, the AGU describes its mission as the advancement of terrestrial, atmospheric and space research aimed at benefiting humanity.

"Reliable docking mechanisms are essential for the operation of underwater vehicles, particularly in harsh environments," Mohseni said. "We set out to resolve the trade off that a number of scientists settle for, which is a faster, but less precise, vehicle or a boxier one that is not as fast and more difficult to transport to work locations".........

Posted by: John      Permalink         Source

December 12, 2006, 4:41 AM CT

Moon's Escaping Gasses

Moon's Escaping Gasses Millions of years – not billions
Image: NAS
It was widely believed that earth's moon has seen no widespread volcanic activity for at least the last 3 billion years. Now, a fresh look at existing data points to much more recent release of lunar gasses.

The study, published in the journal Nature by geologists Peter Schulz and Carle Pieters of Brown University and Matthew Staid of the Planetary Science Institute, uses three distinct lines of evidence to support the assertion that volcanic gas has been released from the moon's surface within the last 1 to 10 million years. The researchers focus on a D-shaped area called the Ina structure that was first recognized in images from Apollo missions.

The unusual sharpness of the features first called Schultz's attention to the area. "Something that razor-sharp shouldn't stay around long. It ought to be destroyed within 50 million years," said Schulz. On Earth, wind and water quickly wear down freshly exposed surface features. On the airless moon, constant bombardment with tiny space debris accomplishes a similar result. By comparing the fine-scale surface features within the Ina structure to other areas on the moon with known ages, the team was able to place its age at closer to 2 million years.

The scarcity of asteroid impact craters on the surface within Ina provided a second line of evidence for the feature's relative youth. The researchers identified only two clear impact craters larger than 30 meters on the 8 square kilometers of the structure's floor. This frequency is about the same as at South Ray Crater, near the Apollo 16 landing site. The surface material ejected from South Ray Crater has long been used as a benchmark for dating other features on the moon's surface and most lunar scientists studying these rocks agree on a date of approximately 2 million years, based on cosmic ray exposure.........

Posted by: Edwin      Permalink         Source

December 11, 2006, 9:43 PM CT

Agricultural Production In Great Lakes

Agricultural Production In Great Lakes Great Lakes area: Africa's most impoverished region
Credit: IFD
The Netherlands Government is launching a project to promote peace and environmental stability by improving soil health, intensifying farm production, and increasing trade in one of the world's poorest areas: the Great Lakes Region of Central Africa.

The highest population density in Africa is in the Great Lakes Region: Rwanda, Burundi, Uganda, western Tanzania, and the eastern Democratic Republic of the Congo.

"The Great Lakes region already has far more people than its fragile soils can support," says Dr. Amit Roy, CEO of IFDC, An International Center for Soil Fertility and Agricultural Development. IFDC will implement the 5-year project.

"The region faces perpetual crises of poverty, social instability, war, and environmental degradation. The situation is rapidly worsening as deforestation intensifies and its soils are starved of nutrients".

Tiny Rwanda is typical. More than 340 persons are packed into each square kilometer, and population is growing by almost 3% annually. Almost all of Rwanda's population are subsistence farmers. Using existing technology, food production can be increased only by clearing and farming the ecologically important wetlands or, worse, the last relicts of parks and reserves, including habitats of mountain gorillas and other endangered wildlife and plants.........

Posted by: Nora      Permalink         Source

December 11, 2006, 9:21 PM CT

Upsetting Notions about Honey Bees

Upsetting Notions about Honey Bees
Genetic research, based on information from the recently released honey bee genome, has toppled some long-held beliefs about the honey bee that colonized Europe and the U.S.

As per research published recently in Science, an international professional journal published by the American Association for the Advancement of Science, the four most common subspecies of honey bee originated in Africa and entered Europe in two separate migrations, said Dr. Spencer Johnston, entomologist with the Texas Agricultural Experiment Station and one of the authors of the article.

A large number of different bee species exist in Asia, where it had long been thought the honey bee originated, Johnston said.

"Their origin in Africa was suggested in other studies, but our result shows it dramatically to be true," he said.

Taking genetic information from the honey bee genome sequencing effort, scientists from Texas A&M University, University of Illinois, Cornell University, Washington State University, University of Kansas and the University of California-Irvine, and one private producer traced the genealogy of honey bees. Two branches originate in Africa.

The honey bee is not native to North America; it was introduced from Europe for honey production in the early 1600s, Johnston said. Subspecies were introduced from Italy in 1859, and later from Spain, Portugal and elsewhere.........

Posted by: Nora      Permalink         Source

December 10, 2006, 9:24 PM CT

A trip to Asteroid Itokawa

A trip to Asteroid Itokawa The Hayabusa craft heads toward the asteroid Itokawa
Itokawa, a spud-shaped, near-Earth asteroid, consists mainly of the minerals olivine and pyroxene, a mineral composition similar to a class of stony meteorites that have pelted Earth in the past.

This asteroid ingredient list, published in Science, comes courtesy of Hayabusa, the spacecraft launched in 2003 by the Japanese Aerospace Exploration Agency (JAXA). The mission of Hayabusa is to bring back first-ever samples from an asteroid to better understand their role as building blocks of the solar system.

Itokawa, an elongated rocky object nearly as long as five football fields, circles the sun more than 321 million miles away from Earth. Along with a few hundred known asteroids, Itokawa's orbit is close to Earth's orbit and was discovered by the Lincoln Near-Earth Asteroid (LINEAR) program, which detects near-Earth asteroids and provides advance warning if any are bound for Earth. Itokawa doesn't currently pose such a threat, but its close proximity made it a tempting scientific target.

A near-infrared spectrometer aboard Hayabusa helped identify Itokawa's mineralogy, mostly a mixture of the rock-forming minerals olivine and pryroxene, and possibly some plagioclase and metallic iron. But to truly understand what they had, the team turned to Takahiro Hiroi, a Brown University researcher who is expert in determining the composition of asteroids and meteorites, bits of asteroids that have fallen to Earth.........

Posted by: Edwin      Permalink         Source

December 10, 2006, 5:27 PM CT

Amazing Forms Of Life

Amazing Forms Of Life Eggs are visible on this deepwater copepod, Eaugaptilis hyperboreus
Image courtesy of cnn
I was reading the news about deep-sea creatures found in the Atlantic Ocean, and thought I might share some of this with you. The report speaks about mysterious creatures that are found in the deep sea. In one place the researchers found Atlantic shrimp, which was living around a vent that was releasing water heated to 765 degree Fahrenheit!

An underwater peak in the Coral Sea was home to a type of shrimp thought to have gone extinct 50 million years ago.

More than 3 miles beneath the Sargasso Sea, in the Atlantic, researchers collected a dozen new species eating each other or living on organic material that drifts down from above.

"Animals seem to have found a way to make a living just about everywhere," said Jesse Ausubel of the Sloan Foundation, discussing the findings of year six of the census of marine life.

Added Ron O'Dor, a senior scientist with the census: "We can't find any place where we can't find anything new".

Read more........

Posted by: Nora      Permalink         Source

December 8, 2006, 4:51 AM CT

Mood Makes Food Taste Different

Mood Makes Food Taste Different
Feeling anxious? Your mood may actually change how your dinner tastes, making the bitter and salty flavours recede, according to new research.

This link between the chemical balance in your brain and your sense of taste could one day help doctors to treat depression. There are currently no on-the-spot tests for deciding which medicine will work best in individual patients with this condition. Researchers hope that a test based on flavour detection could help doctors to get more prescriptions right first time.

It has long been known that people who are depressed have lower-than-usual levels of the brain chemicals serotonin or noradrenaline, or in some cases both. Many also have a blunted sense of taste, which is presumably caused by changes in brain chemistry.

To unpick the relationship between the two, Lucy Donaldson and her colleagues at the University of Bristol, UK, gave 20 healthy volunteers two antidepressant drugs, and checked their sensitivity to different tastes. The drug that raised serotonin levels made people more sensitive to sweet and bitter tastes, the team reports in the Journal of Neuroscience1. The other, which increased noradrenaline, enhanced recognition of bitter and sour tastes.

In healthy people, volunteers whose anxiety levels were naturally higher were less sensitive to bitter and salty tastes.........

Posted by: Edwin      Permalink         Source

December 7, 2006, 4:56 AM CT

For Black Holes Size Does Not Matter

For Black Holes Size Does Not Matter Credit R Hynes
Research by UK astronomers, published recently in Nature (7th December 2006) reveals that the processes at work in black holes of all sizes are the same and that supermassive black holes are simply scaled up versions of small Galactic black holes.

An accreting black hole and a binary star.

Credit: R HynesFor many years astronomers have been trying to understand the similarities between stellar-mass sized Galactic black hole systems and the supermassive black holes in active galactic nuclei (AGN). In particular, do they vary fundamentally in the same way, but perhaps with any characteristic timescales being scaled up in proportion to the mass of the black hole. If so, the researchers proposed, we could determine how AGN should behave on cosmological timescales by studying the brighter and much faster galactic systems.

Professor Ian McHardy, from the University of Southampton, heads up the research team whose findings are published recently (along with colleagues Dr Elmar Koerding, Dr Christian Knigge, Professor Rob Fender and Dr Phil Uttley, currently working at the University of Amsterdam). Their observations were made using data from NASA's Rossi X-ray Timing Explorer and XMM Newton's X-ray Observatory.

Professor McHardy comments, "By studying the way in which the X-ray emission from black hole systems varies, we found that the accretion or 'feeding' process - where the black hole is pulling in material from its surroundings - is the same in black holes of all sizes and that AGN are just scaled-up Galactic black holes. We also found that the way in which the X-ray emission varies is strongly correlated with the width of optical emission lines from black hole systems".........

Posted by: Edwin      Permalink         Source

December 6, 2006, 8:38 PM CT

Magnetic Devices Could Make Computers More Powerful

Magnetic Devices Could Make Computers More Powerful
Scientists have created novel 'spintronic' devices that could point the way for the next generation of more powerful and permanent data storage chips in computers.

Physicist at the Universities of Bath, Bristol and Leeds have discovered a way to precisely control the pattern of magnetic fields in thin magnetic films, which can be used to store information.

The discovery has important consequences for the IT industry, as current technology memory storage has limited scope for develop further. The density with which information can be stored magnetically in permanent memory - hard drives - is reaching a natural limit related to the size of the magnetic particles used. The much faster silicon-chip based random access memory - RAM - in computers loses the information stored when the power is switched off.

The key advance of the recent research has been in developing ways to use high energy beams of gallium ions to artificially control the direction of the magnetic field in regions of cobalt films just a few atoms thick.

The direction of the field can be used to store information: in this case "up" or "down" correspond to the "1" or "0" that form the basis of binary information storage in computers.

Further, the physicists have demonstrated that the direction of these magnetic areas can be "read" by measuring their electrical resistance. This can be done much faster than the system for reading information on current hard drives. They propose that the magnetic state can be switched from "up" to "down" with a short pulse of electrical current, thereby fulfilling all the requirements for a fast magnetic memory cell.........

Posted by: John      Permalink         Source

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