US, Afghan troops kill 11 militants in south

International and Afghan troops killed 11 militants when a raid in Afghanistan's volatile south turned into a gunbattle with Taliban fighters, U.S. forces said Friday.

Fighting broke out during the Thursday night raid targeting a key Taliban insurgent in a village in Helmand province, the military said in a statement. The forces came under fire from militants inside a compound as they advanced and returned fire.

The U.S. military said the insurgent targeted in the attack was involved in making bombs that were used for roadside attacks in northern Helmand province.

One insurgent was captured and 11 killed in the fighting in Lashkar Gar district, west of the provincial capital of Kandahar. The statement said one militant tried to use women and children in the compound as human shields, but the force managed to shoot the man without harming the civilians.

A village elder told coalition forces the Taliban forced them to shelter the group for the night, the statement said.

The U.S. is sending 17,000 additional troops to Afghanistan to stamp out the resurgent Taliban who have taken de facto control of the south and continue to mount attacks through much of the rest of the country.

Senior U.S. officials say President Barack Obama also plans to deploy 4,000 trainers to build up Afghan forces as part of a new strategy to be announced Friday.
Source http://www.google.com/hostednews/ap/article/ALeqM5hvWEqwq3CrRvaQCmt21MfoYhjZJQD9765HJO3

Climate-related Changes on the Antarctic Peninsula Being Driven from the Top and the Bottom of the Ecosystem

Scientists have long established that the Antarctic Peninsula is one of the most rapidly warming spots on Earth. Now, new research using detailed satellite data indicates that the changing climate is affecting not just the penguins at the apex of the food chain, but simultaneously the microscopic life that is the base of the ecosystem.

The research was published in the March 13 edition of Science magazine by researchers with the National Science Foundation's (NSF) LTER (Long Term Ecological Research) program. The LTER, which has 26 sites around the globe, including two in Antarctica, enables tracking of ecological variables over time, so that the mechanisms of climate change impact on ecosystems can be revealed. The specific findings were made by researchers with the Palmer LTER, using data collected near Palmer Station and from the research vessel Laurence M. Gould. Both Palmer Station and the Laurence M. Gould are operated by NSF's Office of Polar Programs.

Hugh Ducklow, of the Marie Biological Laboratory at Woods Hole, the principal investigator for the Palmer LTER project, said that the new findings are scientifically significant, but they also are consistent with the climate trends on the Peninsula and other observed changes.

However, it took new scientific tools and analytical work by post-doctoral fellow Martin Montes Hugo to verify scientifically what scientists had been inferring from other changes for some time.

"I have to say the findings weren't a surprise; I think with the weight of all the other observations that we had on changes happening to organisms higher up in the food chain, we thought that phytoplankton weren't going to escape this level of climate change," Ducklow said. "But it took Martin to have all the right tools and the abilities to go in and do the analysis and prove what we suspected."

Those data, gathered over years, were essential to tracking patterns that supported the new findings.

"That's the beauty of the LTER program," he added.

Over the past 50 years, winter temperatures on the Peninsula have risen five times faster than the global average and the duration of sea-ice coverage has decreased. A warm, moist maritime climate has moved into the northern Peninsula region, pushing the continental, polar conditions southward.

As a result, the prevalence of species that depend on sea ice, such as Adelie penguins, Antarctic silverfish and krill, has decreased in the Peninsula's northern region, and new species that typically avoid ice, such as Gentoo and Chinstrap penguins, and lanternfish are moving into the habitat.

The LTER researchers show that satellite data on ocean color, temperature, sea ice and winds, indicate that phytoplankton at the base of the food chain are also responding to changes in sea-ice cover and winds driven by climate change. However, there are contrasting changes in northern and southern regions, and the satellite and ground-based data provide insights into the forcing mechanisms for each region.

The researchers weren't surprised that primary productivity in the waters of the Peninsula has changed dramatically over the last 20 years. But the contrasting changes in the north and south were a surprise.

Galactic Dust Bunnies Found to Contain Carbon After All

Galactic Dust Bunnies Found to Contain Carbon After All Using NASA's Spitzer Space Telescope, researchers have found evidence suggesting that stars rich in carbon complex molecules may form at the center of our Milky Way galaxy.

This discovery is significant because it adds to our knowledge of how stars form heavy elements -- like oxygen, carbon and iron -- and then blow them out across the universe, making it possible for life to develop.

Astronomers have long been baffled by a strange phenomenon: Why have their telescopes never detected carbon-rich stars at the center of our galaxy even though they have found these stars in other places? Now, by using Spitzer's powerful infrared detectors, a research team has found the elusive carbon stars in the galactic center.

"The dust surrounding the stars emits very strongly at infrared wavelengths," says Pedro García-Lario, a research team member who is on the faculty of the European Space Astronomy Center, the European Space Agency's center for space science. He co-authored a paper on this subject in the February 2009 issue of the journal Astronomy & Astrophysics.

"With the help of Spitzer spectra, we can easily determine whether the material returned by the stars to the interstellar medium is oxygen-rich or carbon-rich."

The team of scientists analyzed the light emitted from 40 planetary nebulae – blobs of dust and gas surrounding stars -- using Spitzer's infrared spectrograph. They analyzed 26 nebulae toward the center of the Milky Way -- a region called the "Galactic Bulge" -- and 14 nebulae in other parts of the galaxy. The scientists found a large amount of crystalline silicates and polycyclic aromatic hydrocarbons, two substances that indicate the presence of oxygen and carbon.

This combination is unusual. In the Milky Way, dust that combines both oxygen and carbon is rare and is usually only found surrounding a binary system of stars. The research team, however, found that the presence of the carbon-oxygen dust in the Galactic Bulge seems to be suggestive of a recent change of chemistry experienced by the star.

The scientists hypothesize that as the central star of a planetary nebula ages and dies, its heavier elements do not make their way to the star's outer layers, as they do in other stars. Only in the last moments of the central star's life, when it expands and then violently expels almost all of its remaining outer gasses, does the carbon become detectable. That's when astronomers see it in the nebula surrounding the star. "The carbon produced through these recurrent 'thermal pulses' is very inefficiently dredged up to the surface of the star, contrary to what is observed in low-metallicity, galactic disk stars," said García-Lario. "It only becomes visible when the star is about to die."

This study supports a hypothesis about why the carbon in some stars does not make its way to the stars' surfaces. Scientists believe that small stars -- those with masses up to one-and-a-half times that of our sun -- that contain lots of metal do not bring carbon to their surfaces as they age. Stars in the Galactic Bulge tend to have more metals than other stars, so the Spitzer data support this commonly held hypothesis. Before the Spitzer study, this hypothesis had never been supported by observation.

This aging and expelling process is typical of all stars. As stars age and die, they burn progressively heavier and heavier elements, beginning with hydrogen and ending with iron. Towards the end of their lives, some stars become what are called "red giants." These dying stars swell so large that if one of them were placed in our solar system, where the sun is now, its outermost border would touch Earth's orbit. As these stars pulsate – losing mass in the process – and then contract, they spew out almost all of their heavier elements. These elements are the building blocks of all planets, including our own Earth (as well as of human beings and any other life forms that may exist in the universe).

FDA CLEARS CAMERA PILL TO PHOTOGRAPH SMALL INTESTINE

FDA today cleared for marketing a swallowable capsule containing a tiny camera that snaps pictures twice a second as it glides through the small intestine.

The product represents a technological advance in methods of examining the gastrointestinal tract.

The device, made by Given Imaging Ltd., an Israeli company with North American headquarters in Norcross, Ga., is intended to visualize the inside of the small intestine to detect polyps, cancer, or causes of bleeding and anemia.

Currently the standard method of detecting abnormalities in the intestines is through endoscopic examination in which doctors advance a scope down into the small intestine via the mouth. However, these scopes are unable to reach through all of the 20-foot-long small intestine, and thus provide only a partial view of that part of the bowel.

The camera capsule is designed to take photos of the entire small intestine, enabling doctors to see areas that the endoscope cannot reach.

The device, called the Given Diagnostic Imaging System, comes in capsule form and contains a camera, lights, transmitter and batteries. The capsule has a clear end that allows the camera to view the lining of the small intestine.

The patient swallows the capsule, and the natural muscular waves of the digestive tract propel it forward through the stomach, into the small intestine, through the large intestine, and then out in the stool. The capsule transmits the images to a data recorder, which is worn on a belt around the patient's waist. The physician then transfers the stored data to a computer for processing and analysis.

The battery has an expected life of eight hours, which is generally long enough to photograph the small intestine, but not long enough to photograph the entire gastrointestinal tract.

FDA cleared the device based on both animal and clinical studies of safety and effectiveness conducted by the manufacturer. In one of the human trials, Given Imaging studied the use of the camera capsule in patients with suspected small intestine disease. All patients had signs of either unexplained chronic gastrointestinal blood loss or anemia. All had undergone standard endoscopic and radiological evaluations prior to receiving the capsule.

Study results showed that the camera pill was safe, without any side effects, and was able to detect abnormalities in the small intestine, including parts that cannot be reached by the endoscope.

FDA cleared the device for use along with--not as a replacement for--other endoscopic and radiological evaluations of the small bowel. The capsule was not studied in the large intestine.