June 20, 2007, 11:08 AM CT

Pipeline of Space Scientists

Students and researchers from around the globe and from throughout the U.S. have come to New York this month to participate in the fourth annual NASA Space Radiation Summer School at the U.S. Department of Energy's Brookhaven National Laboratory. The group will work in Brookhaven Lab's Medical Department and NASA Space Radiation Laboratory (NSRL) - a unique facility that simulates the harsh radiation environment of outer space - to study the possible risks astronauts may face during future long-term space flights. Thirty-nine students have participated in the program to date.

As NASA plans a mission to Mars, an outpost on the Moon, and exploration of near-Earth asteroids, a number of potential health risks to astronauts remain unknown. It is vitally important to learn how human space travelers will be affected by deep-space radiation and how best to protect them from harm. Space radiobiology, a relatively new field that blends the disciplines of physics and biology, addresses these questions.

"While there is a wealth of data describing the effects of conventional radiation like x-rays, the same is not true for the types of radiation present in space. It is essential to define the potential risks of exposure to space radiation and, if necessary, develop effective countermeasures to permit safe missions of longer durations than in the past," explained Peter Guida, Medical Department Liaison Scientist for this program at Brookhaven Lab. Guida is working with Eleanor Blakely of Lawrence Berkeley National Laboratory, the 2007 NASA Summer School Director......... Posted by: Brooke      Read more         Source

June 20, 2007, 10:59 AM CT

New View of Doomed Star

Eta Carinae is a mysterious, extremely bright and unstable star located a mere stone's throw - astronomically speaking - from Earth at a distance of only about 7,500 light years. The star is believed to be consuming its nuclear fuel at an incredible rate, while quickly drawing closer to its ultimate explosive demise. When Eta Carinae does explode, it will be a spectacular fireworks display seen from Earth, perhaps rivaling the moon in brilliance. Its fate has been foreshadowed by the recent discovery of SN2006gy, a supernova in a nearby galaxy that was the brightest stellar explosion ever seen. The erratic behavior of the star that later exploded as SN2006gy suggests that Eta Carinae may explode at any time.

Eta Carinae, a star between 100 and 150 times more massive than the Sun, is near a point of unstable equilibrium where the star's gravity is almost balanced by the outward pressure of the intense radiation generated in the nuclear furnace. This means that slight perturbations of the star might cause enormous ejections of matter from its surface. In the 1840s, Eta Carinae had a massive eruption by ejecting more than 10 times the mass of the sun, to briefly become the second brightest star in the sky. This explosion would have torn most other stars to pieces but somehow Eta Carinae survived......... Posted by: Brooke      Read more         Source

June 20, 2007, 10:04 AM CT

Certain Home Shapes And Roofs Hold Up Best In Hurricane

Certain home shapes and roof types can better resist high winds and hurricanes, as per a researcher at New Jersey Institute of Technology (NJIT). Civil engineer Rima Taher, PhD, special lecturer in the New Jersey School of Architecture at NJIT, spent two years examining the findings of research centers that have studied the best designs and construction materials and methods needed to withstand extreme wind events and hurricanes.

Eventhough Id like to say that there is a simple and economical solution for housing that wont fail or collapse in the perfect storm, such information does still not exist, said Taher. However, it is obvious that thanks to the work of wind engineers and scientists that changes to home design and construction can make buildings safer for people, while saving government and industry billions of dollars annually.

Design of Low-Rise Buildings for Extreme Wind Events (Journal of Architectural Engineering, March, 2007) by Taher highlighted such research findings. Wind scientists at the Center for Building Science and Technology (CSTB) in France, researched and tested reduced-scale home models at its wind tunnel facilities, and developed a prototype of a cyclonic or hurricane-resistant dwelling. Taher cooperated with the CSTB wind researchers, working on the structural aspect of the homes design......... Posted by: Tyler      Read more         Source

June 20, 2007, 9:55 AM CT

Giant magnetocaloric materials for the environment

Materials that change temperature in magnetic fields could lead to new refrigeration technologies that reduce the use of greenhouse gases, thanks to new research at the U.S. Department of Energy's Argonne National Laboratory and Ames National Laboratory.

Researchers carrying out X-ray experimentation at the Advanced Photon Source at Argonne - the nation's most powerful source of X-rays for research - are learning new information about magnetocaloric materials that have potential for environmentally friendly magnetic refrigeration systems.

Magnetic refrigeration is a clean technology that uses magnetic fields to manipulate the degree of ordering (or entropy) of electronic or nuclear magnetic dipoles in order to reduce a material's temperature and allow the material to serve as a refrigerant. New materials for refrigeration based on gadolinium-germanium-silicon alloys display a giant magnetocaloric effect due to unusual coupling between the material's magnetism and chemical structure.

Understanding this coupling is essential to moving this technology from the laboratory to the household. Magnetic refrigeration does not rely on hydrofluorocarbons (HFCs) used in conventional refrigeration systems. HFCs are greenhouse gases that contribute to global climate change when they escape into the atmosphere......... Posted by: Kevin      Read more         Source

June 20, 2007, 9:44 AM CT

How do Americans want to reduce greenhouse gas emissions?

Most Americans now think that global warming is happening, and they want the federal government to take action to limit its effects. But what form should that action take" And does support for action hold firm if people understand how much it may cost them financially" .

To find out, New Scientist, Stanford University and Resources for the Future, an independent think tank, commissioned the survey research firm Knowledge Networks to query a representative sample of American adults.

We investigated three main ways of reducing greenhouse pollution.

1)Standards or mandates: The government tells companies exactly how they must generate electricity or manufacture vehicle fuel to achieve a cut in emissions.

2) Emissions Tax: The government taxes companies for their greenhouse gas emissions.

3) Cap-and-Trade: The government imposes a cap on companies greenhouse gas emissions, but allows companies to trade permits - which represent the right to emit a certain amount of pollution.

The aim of our poll was to test the relative attractiveness of these three options. We told 1,491 adults how each option could work in each of two sectors: vehicle fuel and electricity. We chose these sectors because they are each responsible for a substantial proportion of US greenhouse emissions, and because any costs of making cuts will likely be passed onto consumers. That gave a total of six possible policies, each of which we told respondents would reduce total projected US greenhouse emissions in 2020 by five percent......... Posted by: Tyler      Read more         Source

June 20, 2007, 8:27 AM CT

Uncovering Ancient Human Behaviour

A major question in evolutionary studies today is how early did humans begin to think and behave in ways we would see as fundamentally modern? One index of 'behavioural modernity' is in the appearance of objects used purely as decoration or ornaments. Such items are widely regarded as having symbolic rather than practical value. By displaying them on the body as necklaces, pendants or bracelets or attached to clothing this also greatly increased their visual impact. The appearance of ornaments may be associated with a growing sense of self-awareness and identity amongst humans and any symbolic meanings would have been shared by members of the same group.

In Europe, amongst the oldest known symbolic ornaments are perforated animal teeth and shell beads, found in Upper Palaeolithic contexts that date to no more than 40,000 years ago. Such finds are apparently linked to both modern human and late Neanderthal sites. Together with cave paintings and engravings they offer the strongest indications that European societies of those times were capable of thinking in an abstract manner, and symbolising their ideas without relying on obvious links between a meaning and a sign. But, now, a growing body of evidence indicates symbolic material culture consisting of engravings, personal ornaments and systematic use of beads had emerged much earlier in Africa......... Posted by: William      Read more         Source

June 20, 2007, 8:13 AM CT

The woes of Kilimanjaro

The "snows" of Africa's Mount Kilimanjaro inspired the title of an iconic American short story, but now its dwindling icecap is being cited as proof for human-induced global warming.

However, two scientists writing in the July-August edition of American Scientist magazine say global warming has nothing to do with the decline of Kilimanjaro's ice, and using the mountain in northern Tanzania as a "poster child" for climate change is simply inaccurate.

"There are dozens, if not hundreds, of photos of midlatitude glaciers you could show where there is absolutely no question that they are declining in response to the warming atmosphere," said climatologist Philip Mote, a University of Washington research scientist.

But in the tropics -- especially on Kilimanjaro -- processes are at work that are far different from those that have diminished glacial ice in temperate regions closer to the poles, he said.

Mote and Georg Kaser, a glaciologist at the University of Innsbruck in Austria, write in American Scientist that the decline in Kilimanjaro's ice has been going on for more than a century and that most of it occurred before 1953, while evidence of atmospheric warming there before 1970 is inconclusive.

They attribute the ice decline primarily to complex interacting factors, including the vertical shape of the ice's edge, which allows it to shrink but not expand. They also cite decreased snowfall, which reduces ice buildup and determines how much energy the ice absorbs -- because the whiteness of new snow reflects more sunlight, the lack of new snow allows the ice to absorb more of the sun's energy......... Posted by: Tyler      Read more         Source

June 19, 2007, 4:56 AM CT

Archaeologists rescue clues to ancient kingdom from the rising Nile

Archaeologists from the University of Chicago have discovered a gold processing center along the middle Nile, an installation that produced the precious metal sometime between 2000 and 1500 B.C. The center, along with a cemetery they discovered, documents extensive control by the first sub-Saharan kingdom, the kingdom of Kush.

The team from the Universitys Oriental Institute found more than 55 grinding stones made of granite-like gneiss along the Nile at the site of Hosh el-Geruf, about 225 miles north of Khartoum, Sudan. The region was also known also known as Nubia in ancient times.

Groups of similar grinding stones have been found on desert sites, mostly in Egypt, where they were used to grind ore to recover the precious metal. The ground ore was likely washed with water nearby to separate the gold flakes.

This large number of grinding stones and other tools used to crush and grind ore shows that the site was a center for organized gold production, said Geoff Emberling, Director of the Oriental Institute Museum and a co-leader of the expedition. The research was funded by the the National Geographic Society and the Packard Humanities Institute, which also has offered to support all the teams working in the Fourth Cataract salvage project, the location of the Universitys expedition......... Posted by: William      Read more         Source

June 18, 2007, 10:05 PM CT

Stealth Tsunami That Killed 600 In Java Last Summer

Though categorized as magnitude 7.8, the earthquake could scarcely be felt by beachgoers that afternoon. A low tide and wind-driven waves disguised the signs of receding water, so when the tsunami struck, it caught even lifeguards by surprise. That contributed to the death toll of more than 600 persons in Java, Indonesia.

The general assumption was that if you were near the coast where the earthquake took place, you would feel it and be able to run to higher ground, said Hermann Fritz, first author of a new Geophysical Research Letters paper about the July 17, 2006 tsunami. This event caught people by surprise and showed that its not always that simple.

The earthquake was slow rupturing, so it didnt produce strong ground shaking on Java that might have alerted people on the beach, he explained.

No local warning was issued for the tsunami waves, which arrived only tens of minutes after the earthquake. Fortunately, the event took place on a Monday. Had the massive waves hit the day before, which was a major national holiday, the popular beach would have been much more crowded and the toll higher.

Warning systems typically dont work very well for locations near earthquakes, where there are only tens of minutes between the earthquake and the tsunamis arrival, noted Fritz, a Georgia Institute of Technology assistant professor who led an inspection team to Java a week after the event. Its pretty much a spontaneous self-evacuation. You normally feel the earthquake or see the ocean withdraw. If you hear the noise in the last tens of seconds before it hits, then its just a matter of who makes it and who doesnt......... Posted by: Tyler      Read more         Source

June 13, 2007, 1:30 PM CT

Lung and bladder cancer after arsenic exposure

Arsenic exposure appears to continue causing lung and bladder cancer deaths years after exposure ends, according to a study published online June 12 in the Journal of the National Cancer Institute

Arsenic is a known cause of lung and bladder cancer, but researchers dont yet know how long cancer risk remains elevated after arsenic exposure. The drinking water in a region of northern Chile became contaminated with very high amounts of arsenic beginning in 1958. In the 1970s, construction of water treatment plants in the region led to a decline in arsenic concentration. This sudden rise and fall of arsenic levels gave researchers the opportunity to investigate the period between first and last exposure to high levels of arsenic and subsequent mortality due arsenic-related cancers, such as bladder and lung cancer.

Guillermo Marshall, Ph.D., of Pontificia Universidad Catlica de Chile in Santiago and colleagues including collaborators from the University of California, Berkeley, investigated bladder and lung cancer death rates in the region between 1950 and 2000 and compared them with data from a similar region farther south, where the water was not contaminated.

Lung and bladder cancer mortality rates in the area with arsenic-contaminated drinking water began to rise about 10 years after arsenic levels rose. They then continued to climb, peaking between 10 and 20 years after the arsenic levels dropped. At the peak, lung cancer deaths among men and women in the contaminated region were about three times higher than in the control region, while bladder cancer deaths were six times higher in men and 14 times higher in women. The lag time between exposure to a carcinogen and the peak of cancer deaths is usually difficult to determine, but the size of the study and the record of arsenic exposure aided the researchers......... Posted by: Sarah      Read more         Source