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1351  Main Area and Open Discussion / Living Room / A Supernova Cocoon Breakthrough on: May 15, 2012, 06:27:35 PM
Observations with NASA's Chandra X-ray Observatory have provided the first X-ray evidence of a supernova shock wave breaking through a cocoon of gas surrounding the star that exploded. This discovery may help astronomers understand why some supernovas are much more powerful than others.

On November 3, 2010, a supernova was discovered in the galaxy UGC 5189A, located about 160 million light years away. Using data from the All Sky Automated Survey telescope in Hawaii taken earlier, astronomers determined this supernova exploded in early October 2010 (in Earth's time-frame).

This composite image of UGC 5189A shows X-ray data from Chandra in purple and optical data from Hubble Space Telescope in red, green and blue. SN 2010jl is the very bright X-ray source near the top of the galaxy (mouse-over for a labeled version).

A team of researchers used Chandra to observe this supernova in December 2010 and again in October 2011. The supernova was one of the most luminous that has ever been detected in X-rays.

In optical light, SN 2010jl was about ten times more luminous than a typical supernova resulting from the collapse of a massive star, adding to the class of very luminous supernovas that have been discovered recently with optical surveys. Different explanations have been proposed to explain these energetic supernovas including (1) the interaction of the supernova's blast wave with a dense shell of matter around the pre-supernova star, (2) radioactivity resulting from a pair-instability supernova (triggered by the conversion of gamma rays into particle and anti-particle pairs), and (3) emission powered by a neutron star with an unusually powerful magnetic field.

In the first Chandra observation of SN 2010jl, the X-rays from the explosion's blast wave were strongly absorbed by a cocoon of dense gas around the supernova. This cocoon was formed by gas blown away from the massive star before it exploded.

In the second observation taken almost a year later, there is much less absorption of X-ray emission, indicating that the blast wave from the explosion has broken out of the surrounding cocoon. The Chandra data show that the gas emitting the X-rays has a very high temperature -- greater than 100 million degrees Kelvin -- strong evidence that it has been heated by the supernova blast wave.

Read More: http://www.sciencedaily.c.../2012/05/120515131723.htm
1352  Main Area and Open Discussion / Living Room / This Is Your Brain On Sugar:Study in Rats Shows... on: May 15, 2012, 06:27:04 PM
This Is Your Brain On Sugar: Study in Rats Shows High-Fructose Diet Sabotages Learning, Memory

Attention, college students cramming between midterms and finals: Binging on soda and sweets for as little as six weeks may make you stupid.

A new UCLA rat study is the first to show how a diet steadily high in fructose slows the brain, hampering memory and learning -- and how omega-3 fatty acids can counteract the disruption. The peer-reviewed Journal of Physiology publishes the findings in its May 15 edition.

"Our findings illustrate that what you eat affects how you think," said Fernando Gomez-Pinilla, a professor of neurosurgery at the David Geffen School of Medicine at UCLA and a professor of integrative biology and physiology in the UCLA College of Letters and Science. "Eating a high-fructose diet over the long term alters your brain's ability to learn and remember information. But adding omega-3 fatty acids to your meals can help minimize the damage."

While earlier research has revealed how fructose harms the body through its role in diabetes, obesity and fatty liver, this study is the first to uncover how the sweetener influences the brain.

The UCLA team zeroed in on high-fructose corn syrup, an inexpensive liquid six times sweeter than cane sugar, that is commonly added to processed foods, including soft drinks, condiments, applesauce and baby food. The average American consumes more than 40 pounds of high-fructose corn syrup per year, according to the U.S. Department of Agriculture. "We're not talking about naturally occurring fructose in fruits, which also contain important antioxidants," explained Gomez-Pinilla, who is also a member of UCLA's Brain Research Institute and Brain Injury Research Center. "We're concerned about high-fructose corn syrup that is added to manufactured food products as a sweetener and preservative."

Read More: http://www.sciencedaily.c.../2012/05/120515150938.htm
1353  Main Area and Open Discussion / Living Room / Drugs from Gila Monster Lizard Saliva Reduces Cravings for Chocolate..... on: May 15, 2012, 06:26:23 PM
Drugs from Gila Monster Lizard Saliva Reduces Cravings for Chocolate and Ordinary Food

A drug made from the saliva of the Gila monster lizard is effective in reducing the craving for food. Researchers at the Sahlgrenska Academy, University of Gothenburg, have tested the drug on rats, who after treatment ceased their cravings for ordinary food and also chocolate.

An increasing number of patients suffering from type 2 diabetes are offered a pharmaceutical preparation called Exenatide, which helps them to control their blood sugar. The drug is a synthetic version of a natural substance called exendin-4, which is obtained from a rather unusual source -- the saliva of the Gila monster lizard (Heloderma suspectum), North America's largest lizard.

Unexpected effect

 Researchers at the Sahlgrenska Academy at the University of Gothenburg, have now found an entirely new and unexpected effect of the lizard substance.

Reduces cravings for food

In a study with rats published in the Journal of Neuroscience, Assistant Professor Karolina Skibicka and her colleagues show that exendin-4 effectively reduces the cravings for food.

"This is both unknown and quite unexpected effect," comments an enthusiastic Karolina Skibicka: "Our decision to eat is linked to the same mechanisms in the brain which control addictive behaviours. We have shown that exendin-4 affects the reward and motivation regions of the brain."

Significant findings

The implications of the findings are significant" states Suzanne Dickson, Professor of Physiology at the Sahlgrenska Academy: "Most dieting fails because we are obsessed with the desire to eat, especially tempting foods like sweets. As exendin-4 suppresses the cravings for food, it can help obese people to take control of their weight," suggests Professor Dickson.

Read More: http://www.sciencedaily.c.../2012/05/120515165405.htm
1354  Main Area and Open Discussion / Living Room / Statistical Analysis Projects Future Temperatures in North America on: May 15, 2012, 06:25:40 PM
For the first time, researchers have been able to combine different climate models using spatial statistics -- to project future seasonal temperature changes in regions across North America.

They performed advanced statistical analysis on two different North American regional climate models and were able to estimate projections of temperature changes for the years 2041 to 2070, as well as the certainty of those projections.

The analysis, developed by statisticians at Ohio State University, examines groups of regional climate models, finds the commonalities between them, and determines how much weight each individual climate projection should get in a consensus climate estimate.

Through maps on the statisticians' website (, people can see how their own region's temperature will likely change by 2070 -- overall, and for individual seasons of the year.

Given the complexity and variety of climate models produced by different research groups around the world, there is a need for a tool that can analyze groups of them together, explained Noel Cressie, professor of statistics and director of Ohio State's Program in Spatial Statistics and Environmental Statistics.

Read More: http://www.sciencedaily.c.../2012/05/120515131634.htm
1355  Main Area and Open Discussion / Living Room / Tiny Plants Could Cut Costs, Shrink Environmental Footprint on: May 15, 2012, 06:25:12 PM
Tall, waving corn fields that line Midwestern roads may one day be replaced by dwarfed versions that require less water, fertilizer and other inputs, thanks to a fungicide commonly used on golf courses.

Burkhard Schulz, a Purdue University assistant professor of plant biochemical and molecular genetics, had earlier found that knocking out the steroid function in corn plants would create tiny versions that only had female sex characteristics. But brassinazole, the chemical used to inhibit the plant steroid biosynthesis, was prohibitively expensive.

One gram of brassinazole could cost as much as $25,000, so Schulz started looking into other options. He found that propiconazole, used to treat fungal dollar spot disease on golf courses, is more potent and costs about 10 cents for the same amount.

"Any research where you needed to treat large plants for long periods of time would have been impossible," Schulz said. "Those tests before would have cost us millions of dollars. Now, they cost us $25. This will open up research in crops that was not possible before."

Schulz's earlier work showed that inhibiting steroids in maize produced short, feminized versions of the plants that developed more kernels where pollen would normally grow. Those findings came from adding chemicals and altering genes to disrupt steroid production. His new finding shows that a widely available fungicide can do the same thing.

"We can change the architecture of a plant the same way that has been done through breeding," said Schulz, whose findings were published in the journal PLoS One. "We can treat plants with this substance throughout the plant's life and it will never be able to produce steroids."

That could be significant for seed producers, who must mechanically remove tassels, the male portion of the plants, so that they do not pollinate themselves. The process is labor-intensive.

Shorter plants that produce the same amount of grain could also reduce agriculture's environmental footprint. Those plants would need much less water, fertilizer and pesticides. Schulz said wider application on golf courses could also slow grass growth, minimizing the amount of mowing that would have to be done.

Read More: http://www.sciencedaily.c.../2012/05/120515104638.htm
1356  Main Area and Open Discussion / Living Room / Surgeons Restore Some Hand Function to Quadriplegic Patient on: May 15, 2012, 06:24:37 PM
Surgeons at Washington University School of Medicine in St. Louis have restored some hand function in a quadriplegic patient with a spinal cord injury at the C7 vertebra, the lowest bone in the neck. Instead of operating on the spine itself, the surgeons rerouted working nerves in the upper arms. These nerves still "talk" to the brain because they attach to the spine above the injury.

Following the surgery, performed at Barnes-Jewish Hospital, and one year of intensive physical therapy, the patient regained some hand function, specifically the ability to bend the thumb and index finger. He can now feed himself bite-size pieces of food and write with assistance.

The case study, published online May 15 in the Journal of Neurosurgery, is, to the authors' knowledge, the first reported case of restoring the ability to flex the thumb and index finger after a spinal cord injury.

"This procedure is unusual for treating quadriplegia because we do not attempt to go back into the spinal cord where the injury is," says surgeon Ida K. Fox, MD, assistant professor of plastic and reconstructive surgery at Washington University, who treats patients at Barnes-Jewish Hospital. "Instead, we go out to where we know things work -- in this case the elbow -- so that we can borrow nerves there and reroute them to give hand function."

Although patients with spinal cord injuries at the C6 and C7 vertebra have no hand function, they do have shoulder, elbow and some wrist function because the associated nerves attach to the spinal cord above the injury and connect to the brain. Since the surgeon must tap into these working nerves, the technique will not benefit patients who have lost all arm function due to higher injuries -- in vertebrae C1 through C5.

The surgery was developed and performed by the study's senior author Susan E. Mackinnon, MD, chief of the Division of Plastic and Reconstructive Surgery at Washington University School of Medicine. Specializing in injuries to peripheral nerves, she has pioneered similar surgeries to return function to injured arms and legs.

Read More: http://www.sciencedaily.c.../2012/05/120515104500.htm
1357  Main Area and Open Discussion / Living Room / Black Holes Turn Up the Heat for the Universe on: May 15, 2012, 06:23:52 PM
Astrophysicists have just discovered a new heating source in cosmological structure formation. Until now, astrophysicists thought that super-massive black holes could only influence their immediate surroundings. A collaboration of scientists at the Heidelberg Institute for Theoretical Studies (HITS) and in Canada and the US have now discovered that diffuse gas in the universe can absorb luminous gamma-ray emission from black holes, heating it up strongly. This surprising result has important implications for the formation of structures in the universe.

The results have just been published in The Astrophysical Journal and Monthly Notices of the Royal Astronomical Society.

Every galaxy hosts a supermassive black hole at its center. Such black holes can emit high-energy gamma rays and are then called blazars. Whereas other radiation such as visible light and radio waves traverses the universe without problems, this is not the case for high-energy gamma rays. This particular radiation interacts with the optical light that is emitted by galaxies, transforming it into the elementary particles electrons and positrons. Initially, these elementary particles move almost at the speed of light. But as they are slowed down by the ambient diffuse gas, their energy is converted into heat, just like in other braking processes. As a result, the surrounding gas is heated efficiently. In fact, the temperature of the gas at mean density becomes ten times higher, and in "under-dense" regions more than one hundred times higher than previously thought.

A Journey into the Cosmic Youth

"Blazars rewrite the thermal history of the universe," emphasizes Dr. Christoph Pfrommer (HITS), one of the authors. But how can this idea be tested? In the optical spectra of quasars there is a plethora of lines, called the "line forest." The forest originates from the absorption of ultra-violet light by neutral hydrogen in the young Universe. If the gas becomes hotter, weak lines in the forest are broadened. This effect represents an excellent opportunity to measure temperatures in the early Universe, while it was still growing up. The astrophysicists at HITS checked this newly postulated heating process for the first time with detailed supercomputer simulations of the cosmological growth of structures. Surprisingly, the lines were broadened just enough so that their properties perfectly matched those of the observed lines. "This allows us to elegantly solve a long-standing problem with the quasar data," says Dr. Ewald Puchwein, who conducted the large simulations on the supercomputer at HITS.

Read More: http://www.sciencedaily.c.../2012/05/120515093947.htm
1358  Main Area and Open Discussion / Living Room / Sleepwalking More Prevalent Among U.S. Adults Than Previously Suspected on: May 15, 2012, 06:23:11 PM
What goes bump in the night? In many U.S. households: people. That's according to new Stanford University School of Medicine research, which found that about 3.6 percent of U.S. adults -- or upward of 8.4 million -- are prone to sleepwalking. The work also showed an association between nocturnal wanderings and certain psychiatric disorders, such as depression and anxiety.

The study, the researchers noted, "underscores the fact that sleepwalking is much more prevalent in adults than previously appreciated."

Maurice Ohayon, MD, DSc, PhD, professor of psychiatry and behavioral sciences, is the lead author of the paper, which appeared in the May 15 issue of Neurology, the medical journal of the American Academy of Neurology.

Sleepwalking is a disorder "of arousal from non-REM sleep." While wandering around at night can be harmless and is often played for laughs -- anyone remember the Simpsons episode where Homer began wandering around and doing silly things in his sleep? -- sleepwalking can have serious consequences. Episodes can result in injuries to the wanderer or others and lead to impaired psychosocial functioning.

It is thought that medication use and certain psychological and psychiatric conditions can trigger sleepwalking, but the exact causes are unknown. Also unclear to experts in the field is the prevalence.

"Apart from a study we did 10 years ago in the European general population, where we reported a prevalence of 2 percent of sleepwalking," the researchers wrote in their paper, "there are nearly no data regarding the prevalence of nocturnal wanderings in the adult general population. In the United States, the only prevalence rate was published 30 years ago."

For this study, the first to use a large, representative sample of the U.S. general population to demonstrate the number of sleepwalkers, the researchers also aimed to evaluate the importance of medication use and mental disorders associated with sleepwalking. Ohayon and his colleagues secured a sample of 19,136 individuals from 15 states and then used phone surveys to gather information on participants' mental health, medical history and medication use.

Read More: http://www.sciencedaily.c.../2012/05/120514161614.htm
1359  Main Area and Open Discussion / Living Room / Scientists Generate Electricity from Viruses on: May 15, 2012, 06:22:34 PM
ScienceDaily (May 13, 2012) — Imagine charging your phone as you walk, thanks to a paper-thin generator embedded in the sole of your shoe. This futuristic scenario is now a little closer to reality. Scientists from the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a way to generate power using harmless viruses that convert mechanical energy into electricity.

The scientists tested their approach by creating a generator that produces enough current to operate a small liquid-crystal display. It works by tapping a finger on a postage stamp-sized electrode coated with specially engineered viruses. The viruses convert the force of the tap into an electric charge.

Their generator is the first to produce electricity by harnessing the piezoelectric properties of a biological material. Piezoelectricity is the accumulation of a charge in a solid in response to mechanical stress.

The milestone could lead to tiny devices that harvest electrical energy from the vibrations of everyday tasks such as shutting a door or climbing stairs.

It also points to a simpler way to make microelectronic devices. That's because the viruses arrange themselves into an orderly film that enables the generator to work. Self-assembly is a much sought after goal in the finicky world of nanotechnology.

The scientists describe their work in a May 13 advance online publication of the journal Nature Nanotechnology.

"More research is needed, but our work is a promising first step toward the development of personal power generators, actuators for use in nano-devices, and other devices based on viral electronics," says Seung-Wuk Lee, a faculty scientist in Berkeley Lab's Physical Biosciences Division and a UC Berkeley associate professor of bioengineering.

He conducted the research with a team that includes Ramamoorthy Ramesh, a scientist in Berkeley Lab's Materials Sciences Division and a professor of materials sciences, engineering, and physics at UC Berkeley; and Byung Yang Lee of Berkeley Lab's Physical Biosciences Division.

The piezoelectric effect was discovered in 1880 and has since been found in crystals, ceramics, bone, proteins, and DNA. It's also been put to use. Electric cigarette lighters and scanning probe microscopes couldn't work without it, to name a few applications.

But the materials used to make piezoelectric devices are toxic and very difficult to work with, which limits the widespread use of the technology.

Lee and colleagues wondered if a virus studied in labs worldwide offered a better way. The M13 bacteriophage only attacks bacteria and is benign to people. Being a virus, it replicates itself by the millions within hours, so there's always a steady supply. It's easy to genetically engineer. And large numbers of the rod-shaped viruses naturally orient themselves into well-ordered films, much the way that chopsticks align themselves in a box.

These are the traits that scientists look for in a nano building block. But the Berkeley Lab researchers first had to determine if the M13 virus is piezoelectric. Lee turned to Ramesh, an expert in studying the electrical properties of thin films at the nanoscale. They applied an electrical field to a film of M13 viruses and watched what happened using a special microscope. Helical proteins that coat the viruses twisted and turned in response -- a sure sign of the piezoelectric effect at work.

Next, the scientists increased the virus's piezoelectric strength. They used genetic engineering to add four negatively charged amino acid residues to one end of the helical proteins that coat the virus. These residues increase the charge difference between the proteins' positive and negative ends, which boosts the voltage of the virus.

Read More: http://www.sciencedaily.c.../2012/05/120513144619.htm
1360  Main Area and Open Discussion / Living Room / Natural sinks still sopping up carbon on: May 15, 2012, 06:21:30 PM
BOULDER, Colo. — Earth’s ecosystems keep soaking up more carbon as greenhouse gases accumulate in the atmosphere, new measurements find.

The research contradicts several recent studies suggesting that “carbon sinks” have reached or passed their capacity. By looking at global measurements of atmospheric carbon dioxide, the new work calculates instead that total sinks have increased roughly in line with rising emissions.

“The sinks have been more than able to keep up with emissions,” said Pieter Tans, an atmospheric scientist at the National Oceanic and Atmospheric Administration’s Earth System Research Laboratory in Boulder, Colo. Tans presented the findings May 15 at an annual conference on global monitoring hosted by the lab.

Careful measurements of atmospheric carbon dioxide taken in the rarefied air atop Mauna Loa, Hawaii, and elsewhere have established that levels of the gas are rising steadily, from 316 parts per million in 1959 to 392 parts per million today. The question is how Earth’s great ecosystems respond to that increase. Forests can suck down carbon dioxide through photosynthesis, whereas oceans take it up proportionally as levels rise in the air.

Previous work has relied on carbon inventories that gather data from multiple sources to try to estimate how much is being put into the atmosphere and how much is being taken out every year. For the new study, Tans and his colleagues went back to basics, choosing 42 marine sites where carbon dioxide levels have been measured for decades.

The researchers then analyzed how much carbon dioxide was in the atmosphere above each of these sites over time. “Less carbon dioxide has remained in the atmosphere, relative to the amount of fossil fuel emissions, today compared to 50 years ago,” Tans said. Even including the effects of land use change, which may alter carbon sinks, produced no measurable trend, he added.

Exactly where the sinks are isn’t clear. One possibility is that forests are regrowing in parts of the world more than scientists had thought, sucking up carbon in the process. Or the oceans may be taking up significantly more carbon than researchers had estimated.

Ralph Keeling, an atmospheric scientist at the Scripps Institution of Oceanography in San Diego, agrees that both land and the oceans aren’t yet done absorbing all the carbon they can. “The land is responding in a big way” to increasing fossil fuel emissions, he says.

Both Keeling and Tans warn that society shouldn’t get complacent just because carbon is still being absorbed. Rising levels of atmospheric greenhouse gases are triggering other planet-wide changes, such as alterations to the oceans’ chemistry. “The situation is bad enough,” Keeling says, “even with the sinks hanging in there.”

Source: http://www.sciencenews.or...s_still_sopping_up_carbon
1361  Main Area and Open Discussion / Living Room / Even moderate noise may harm hearing on: May 15, 2012, 06:21:05 PM
Constant low-level noise might cause hearing problems, a new study in rats finds. The discovery, published online May 15 in Nature Communications, suggests that extended exposure to noise at levels usually deemed safe for human ears could actually impair sound perception.

The findings are “definitely a warning flag,” says study coauthor Michael Merzenich, an integrative neuroscientist at the University of California, San Francisco. He adds that it will be important to find out whether people employed at factories where continuous low-intensity noise is emitted throughout the workday experience similar consequences.

“The big picture is that there is no safe sound,” says Jos Eggermont, an auditory neuroscientist at the University of Calgary in Canada. Even sounds considered safe can cause damage if delivered in a repetitive way, he says. “There might be not-so-subtle effects that accumulate and affect communication and speech understanding.”

It’s common knowledge that sustained exposure to louder noises — such as that above 85 decibels — or brief exposures to very loud noises above 100 decibels can cause inner ear damage and hearing impairments. But until recently, the impact of chronic, quieter sound hasn’t been well studied.

In the new study, Merzenich and his colleague Xiaoming Zhou of East China Normal University in Shanghai exposed adult mice to 65 decibel sound — roughly at the higher end of normal human speech volume — for 10 hours daily. Because low, monotone hums don’t usually excite the brain, the researchers delivered the noise to rats in three to 18 pulses per second. The researchers also exposed another group of rats to similar low-level sound over 24 hours.

After two months of sound conditioning, scientists found that the noise-exposed rats did not perform as well on listening tests compared with animals that lived a quieter life. The tests — which involved distinguishing a sequence of 6.3 pulses per second from another sound pattern of 20 pulses per second — assessed how well the animals could pick out slight variations in sounds, which is important for processes like speech understanding.

In exposed rats, nerve cells in the part of the brain where sounds are processed tended to be less responsive to the more rapid sound pulses than nerve cells in unexposed rats. The noise-exposed animals also had fewer nerve cells that are involved in detecting sharp sound and tended to have higher levels of a protein that’s involved in reshaping how the brain handles information. This finding could mean that the brains of these animals are being altered by sound conditioning.

“These are not necessarily lifelong impairments but they are significant ones and it’s a cause for concern,” says auditory neuroscientist Larry Roberts from McMaster University in Hamilton, Canada.

Still, Eggermont cautions that it’s not clear to what extent these findings can be applied to humans. Although some workplace sounds are repetitive, they aren’t as constant as the ones in the experiments. And employees are exposed to a range of other sounds outside of work, such as music and television, that could also affect their hearing.

Source: http://www.sciencenews.or...te_noise_may_harm_hearing
1362  Main Area and Open Discussion / Living Room / Gene study links stronger memories, PTSD on: May 15, 2012, 06:19:33 PM
A certain genetic signature gives some people the ability to form stronger memories. But that edge also has a dark side: increased risk of post-traumatic stress disorder.

Although the genetic effect is small, the results help scientists better understand the link between especially powerful memories and sensitivity to past trauma.

Scientists led by neuroscientist Dominique de Quervain of the University of Basel in Switzerland looked at how genetic differences related to a memory task. A population of 723 healthy young Swiss adults viewed 72 photographs. After a 10-minute wait, the volunteers were asked to remember as many images as possible.

Volunteers who could remember more pictures carried a particular DNA signature in at least one copy of a gene that encodes protein kinase C alpha. In animal studies, this protein has been shown to play a role in the formation of emotional memories. The volunteers’ heightened recall was true for disturbing, pleasant and neutral pictures.

Further evidence came from brain scans performed in a different group of Swiss people. While viewing the pictures, people with the genetic signature had stronger brain activation in parts of the prefrontal cortex compared with those who lacked the genetic feature, the researchers report online the week of May 14 in the Proceedings of the National Academy of Sciences.

Because memory is known to be an important part of PTSD, de Quervain and his team wanted to see if their results might have importance beyond the laboratory. The researchers looked at the genes of 347 people who had survived the brutal 1994 Rwandan genocide and now live in a refugee camp in Uganda. The genocide was marked by extreme violence and war rape. About a third of those studied met the clinical criteria for PTSD.

Among the Rwandan refugees, having the strong-memory signature was linked to a doubled risk of PTSD compared with the rate among those without the genetic signature. The signature was relatively rare in the Rwandan population, even though it was almost universal among the Swiss.

“I think this work is of great theoretical interest,” says PTSD researcher Roger Pitman of Massachusetts General Hospital and Harvard Medical School. The study supports the idea that stronger memories are linked to a heightened risk of PTSD, a theory that’s been discussed but hasn’t had much evidence, he says. “This is another piece of the puzzle.”

The results explain only a small sliver of memory formation and PTSD. “But that doesn’t mean this gene isn’t important,” de Quervain says. The results give a deeper understanding of the link between strong memories and diseases such as PTSD, he says. Studying the role of protein kinase C alpha may reveal more about how memories form and perhaps even why some prove so troubling.

Source: http://www.sciencenews.or...stronger_memories%2C_PTSD
1363  Main Area and Open Discussion / Living Room / Climate change may leave many mammals homeless on: May 15, 2012, 06:19:04 PM
Some 9 percent of mammal species throughout the Western Hemisphere could, within roughly a century, become climate refugees with no suitable homes, a new study finds. In some areas conditions will be far worse, with 39 to 50 percent of mammals unable to emigrate fast enough to find suitable ecosystems.

“If species can’t migrate spontaneously, they’re going to go extinct. That’s the bottom line,” says Nina Hewitt of York University in Toronto, a biogeographer who was not involved in the new analyses.

The work is not the first study to gauge whether species will keep pace with climate-induced changes to their environments, including a warming or drying. But earlier efforts merely looked at an ideal climate for some species and then evaluated whether and where these conditions might exist decades down the line. Such studies “assumed if a suitable climate existed, the species would move there,” explains Carrie Schloss of the University of Washington in Seattle. Schloss led the new study, which appeared online the week of May 14 in the Proceedings of the National Academy of Sciences.

The new study accounts for species’ dispersal rates — how far each can travel to establish new homes and how frequently such relocations occur.

Mammals don’t typically move much until they prepare to breed. The new analyses of 493 mammal species found many simply cannot move quickly enough to reach hospitable new ranges. Sometimes they’re too small, as in the case of moles and other small rodents. Biology — what age a species reaches reproductive maturity and how often it breeds — also can severely limit relocation rates. This proved especially true for monkeys, which are especially likely to become climate refugees.

The Washington team looked at projections for the Americas from 10 different global-climate computer programs for the period 1961 to 2071. “When dispersal is ignored, the ranges of 149 of the 493 mammalian species in this study are on average projected to expand,” Schloss says. But including how far each species can travel to new homes reversed the trend and projected a range contraction for 86 of these species, or nearly 60 percent.

Even these assessments have probably underestimated the ability of mammals to keep pace with climate, Schloss acknowledges, since her team unrealistically assumed all species will reproduce at the youngest age possible and head for new home ranges in precisely the right directions.

Moreover, adds ecologist Shaye Wolf of the Center for Biological Diversity in San Francisco, this analysis doesn’t account for additional factors, such as whether a migrating species’ food will exist in its newfound home or whether the animal will confront new or more aggressive predators and competitors.

Still, accounting for species dispersal impacts “represents an important new contribution to evaluating whether animals will be able to keep pace with climate change,” she says. 

Hewitt agrees. The new analysis also points to where species conservation biologists may want to focus their efforts for developing migration corridors for animals that will need to move, she says, or programs to otherwise assist imperiled species in reaching a new home range.

Source: http://www.sciencenews.or...e_many_mammals_homeless__
1364  Main Area and Open Discussion / Living Room / Genes may influence body's bacteria on: May 15, 2012, 06:18:37 PM
COLD SPRING HARBOR, N.Y. — Microbes aren’t completely the boss of their human hosts. People’s genes may have a say in which microbes come to live in and on the human body, a new study suggests.

Recent research has shown that the mix of microbes living in and on the human body is associated with some diseases. But exactly what determines which microbes settle a particular human host has been a mystery. Diet and geography are partially responsible, but the part human genetics plays in determining the microbial mix on the body has been unclear.

“We know there is a genetic component,” says Ran Blekhman, a geneticist at Cornell University. “We’re just not sure how big it is.”

To find out, Blekhman and his colleagues turned to data collected by the Human Microbiome Project, an effort to genetically catalog the microbes living in and on the human body. Though the project looks for bacterial DNA in swabs of skin, mouths, feces and other sources, some human genetic material is shed in the samples too. The researchers combed the bacterial DNA data for traces of human DNA contamination, and found enough to reconstruct genetic profiles of 100 people.

Comparing the human and bacterial data revealed 51 different human genetic variants that are associated with the relative abundance of certain bacteria living in or on 15 body sites. Some of those genetic variants and the microbes they were associated with have also been linked to diseases. People with a genetic variant near the PCSK2 gene, which is involved in producing insulin, have more Bacteroides bacteria in their intestines, Blekhman reported May 9 at the Biology of Genomes meeting. That same genetic variant has been linked to type 2 diabetes. So has an overabundance of Bacteroides.

People who have a version of the CXCL12 gene previously associated with inflammatory diseases also carry more Granulicatella bacteria on their skin. Those bacteria have previously been linked to skin inflammation.

The findings present a chicken-versus-egg problem, Blekhman says. Still undetermined is if the bacteria are triggering disease in people who carry certain genetic variants, or if the diseases caused by genetic variants lead to more growth of some types of bacteria. 

Doctors might be able to use bacterial mixes as markers that patients are at risk of getting certain diseases, says Benjamin Voight, a geneticist at the University of Pennsylvania. But first the researchers will need to establish a convincing statistical argument that genes, diseases and microbes are linked. “There are arrows pointing in the right direction,” Voight says. “It’s an interesting observation.

Source: http://www.sciencenews.or..._influence_bodys_bacteria
1365  Main Area and Open Discussion / Living Room / Gene appears linked with a person's daily rhythms on: May 15, 2012, 06:18:15 PM
The settings for a person’s biological clock might provide clues to when, during the day, he or she will be more active. What’s more, these same settings could be linked to what time of day a person might die, a new study finds.

Understanding the biological basis of these built-in, or circadian, clocks “could lead to products that eventually allow us to shift the clock forwards or backwards,” says Philip De Jager, a neurologist with Harvard Medical School in Boston. He and his colleagues describe their work online April 26 in Annals of Neurology.

Being able to alter these clocks could prove useful for shift workers, such as pilots, who might face trouble working against their intrinsic daily rhythms, De Jager adds. And patients can be better cared for if doctors know what times of day are most critical.

Previously, scientists have shown that many genes are involved in regulating people’s inherent daily wake and sleep patterns. Disruptions to this natural circadian rhythm are often linked to serious health conditions, including diabetes.

In the new work, De Jager’s team took a close look at common subtle tweaks that occur in a circadian clock-regulating gene called PER1. By mostly focusing on DNA samples collected from a group of 537 older adults of European ancestry, the team found that there were three different variations of PER1. The researchers also found these variations in another smaller group of 38 people between 18 and 72 years old.

The specific variations were associated with certain times of the day when a person was most active. Peak activity levels differed by about an hour between the groups of individuals with particular variations.

The variations also appeared to be linked to a person’s time of death, scientists found after analyzing a larger sample of 687 older people. Patients with one kind of tweak to PER1 tended to die earlier in the day, at about 11 a.m., while others with a different tweak to the gene passed away hours later, at about 6 p.m.

Data analyzed in the study was gathered for other projects, and the researchers don’t know how these patients died.

Still, deaths linked to certain times of the day are not unusual, says Satchidananda Panda at the Salk Institute for Biological Studies in San Diego. Because the heart beats more rapidly right before a person wakes up, patients with heart conditions are most vulnerable earlier in the day, as they rustle out of bed.

So PER1 variations “might be weakening one or multiple organs that need to crank up at certain times of the day. That’s why you might see these deaths,” explains Panda.

But further work is needed, he says, to look at the exact role of these gene variations and whether they are associated with any medical conditions.

Source: http://www.sciencenews.or...h_a_persons_daily_rhythms
1366  Main Area and Open Discussion / Living Room / Twitter embraces UK's policymakers after eventful year on: May 15, 2012, 06:15:15 PM
Twitter has told the BBC it now wants to work closer with government and policymakers in the UK.

The site has revealed that there are over 10 million active tweeters across the nation.

The site's UK general manager Tony Wang said it is a priority to "protect and defend" the voice of those users.

It has been a year since Twitter opened its UK operations. It has faced tough questions over privacy and regulation.

The network said it now has over 140 million active users worldwide. In the UK, 80% of active users access the site through their mobile, compared to 55% globally.

Now, Mr Wang said the company is looking to work closer in the public sector. As part of a massive worldwide recruiting push, the company is hiring a public policy manager.

Mr Wang said the new recruit would work with "the government, various ministries, members of parliament as well as law enforcement".

"There are a number of different needs that they have - and there's a lot of very unique ways that they're using Twitter," he added.

Read More:
1367  Main Area and Open Discussion / Living Room / Firefox native version hits Android in beta, new UI and speedups tag along on: May 15, 2012, 06:13:24 PM

Those who've liked Firefox for Android but have been clamoring for a native version can rest easy, as there's now a truly optimized version waiting for you in Google Play. Mozilla's new Firefox 14.0 beta now looks like, and importantly runs like, a full member of the Android family. Making the leap also affords it Flash support, a new starting page with top sites, secure Google searches and a slew of load time and responsiveness upgrades over the creakier, XUL-based version. Beta status should still trigger a moment of pause if you're not ready to accept a few bugs, but if you've got Android 2.2 or later, you're welcome to give Firefox a shot.

1368  Main Area and Open Discussion / Living Room / NVIDIA CEO Jen-Hsun Huang announces cloud-based... on: May 15, 2012, 06:11:38 PM
NVIDIA CEO Jen-Hsun Huang announces cloud-based, virtualized Kepler GPU technology and GeForce GRID gaming platform

We're here at NVIDIA's GPU technology conference here in San Jose, California and CEO Jen-Hsun Huang just let loose that his company plans to put Kepler in the cloud. To make it happen, the company has created a virtualized Kepler GPU tech, called VGX, so that no physical connections are needed to render and stream graphics to remote locations. So, as Citrix brought CPU virtualization to put your work desktop on the device of your choosing, NVIDIA has put the power of Kepler into everything from iPads to netbooks and mobile phones.

 While the virtualized GPU has application in an enterprise setting, it also, naturally, can put some serious gaming power in the cloud, too. Fear not, for Jen-Hsun's crew has created GeForce GRID technology that leverages Kepler's cloud capabilities to augment online gaming services like Gaikai by greatly reducing input latency by up to 30ms. Naturally, NVIDIA's not spilling the secret sauce that makes it happen, but you can read all about the new technology at the PR and source below.

1369  Main Area and Open Discussion / Living Room / Google reportedly planning stable of Nexus devices with Android 5.0... on: May 15, 2012, 06:07:49 PM
Google reportedly planning stable of Nexus devices with Android 5.0, will sell 'em direct

Hand firmly grasping hat? Good. The Wall Street Journal is reporting on quite the bombshell today, noting that Google is about to cause its carrier partners in the States all sorts of grief -- indirectly, of course. Just weeks after placing its heralded Galaxy Nexus on sale for $399 unlocked, the report states that said move is only the beginning of a new initiative. Likely to be formally revealed at Google I/O, the mega-corp is planning to partner with a variety of OEMs (rather than just one at a time) in order to have up to five Pure Google (read: Nexus) devices available at once. Better still, the whole stable will ship with Android 5.0 (Jelly Bean) and will be sold directly from Google in unlocked form to consumers in America, Europe and Asia.

 The move is significant in a myriad ways. For one, more unlocked Nexus devices means more choice when it comes to carrier selection. Furthermore, the move is likely to quell fears that certain partners may have about Google making Motorola Mobility its favorite after a $12 billion acquisition. Not surprisingly, Google's not commenting on the matter, but sources "close" to the situation say that the company's hoping to have the 5.0 cadre on sale by Thanksgiving -- you know, just in time for Black Friday and the looming holiday shopping season. We're all guessing that this will address the growing "app situation" head-on; by making a push to eliminate carrier-infused bloatware (while also providing early Android OS access to more partners), we're hoping that the whole "skinning" dilemma is addressed, too.

1370  Main Area and Open Discussion / Living Room / Light-powered bionic eye invented to help restore sight on: May 15, 2012, 06:05:28 PM

A retinal implant - or bionic eye - which is powered by light has been invented by scientists at Stanford University in California.

Implants currently used in patients need to be powered by a battery.

The new device, described in the journal Nature Photonics, uses a special pair of glasses to beam near infrared light into the eye.

This powers the implant and sends the information which could help a patient see.

Diseases such as age-related macular degeneration and retinal pigmentosa result in the death of cells which can detect light in the eye.

Eventually this leads to blindness.
Wiring eliminated

Retinal implants stimulate the nerves in the back of the eye, which has helped some patients to see.

Early results of a trial in the UK mean two men have gone from being totally blind to being able to perceive light and even some shapes.

However, as well as a fitting a chip behind the retina, a battery needs to be fitted behind the ear and a cable needs to join the two together.

Prof Robert MacLaren from Oxford Eye Hospital explains how a bionic eye implant works

The Stanford researchers say their method could be a step forward by "eliminating the need for complex electronics and wiring".

Read More:

1371  Main Area and Open Discussion / Living Room / Apple drops '4G' from iPad adverts on: May 15, 2012, 06:04:16 PM
Apple has stopped using the phrase 4G in adverts for its latest iPad.

The description proved controversial because 4G is not widely available in the UK and the iPad will not work with it when it is.

The UK's advertising watchdog and others around the world investigated Apple over use of the 4G phrase.

Apple said the confusion arose because of the ways operators refer to different high-speed mobile technologies.
Word jumble

When the newest version of the iPad was launched in March, adverts for the device claimed it would work with 4G, meaning fourth generation, mobile technology. The 4G in question was a technology known as Long Term Evolution (LTE) that was starting to appear in the US.

However, when LTE arrives in Britain, the rest of Europe and many other nations, it will use different frequencies from those in the US, meaning the iPad will not be able to use 4G everywhere.

Read More:
1372  Main Area and Open Discussion / Living Room / Nokia accuses Apple of Siri bias over smartphone answer on: May 15, 2012, 06:02:18 PM
The debate over "what is the best smartphone ever?" took an unexpected twist after Apple's voice-activated assistant Siri appeared to favour the iPhone's rival.

Over the weekend, users of Siri were told the answer was Nokia's Lumia 900.

But Siri now responds to the same question with a jovial: "Wait... there are other phones?"

Nokia has accused Apple of "overriding the software" after the quirk was noticed.

Apple would not confirm that a change had been made.

The Siri software, which is featured on Apple's iPhone 4S, uses the computational search engine Wolfram Alpha to serve answers to some questions.

For a question such as "what is the best smartphone ever?", Wolfram Alpha would pool available reviews and comment in order to come up with what it feels is the right result.

Read More:
1373  Main Area and Open Discussion / Living Room / GM to yank $10M in Facebook ads, saying they don't work on: May 15, 2012, 06:00:48 PM
The automaker began re-evaluating its Facebook strategy earlier this year. According to the Wall Street Journal, General Motors determined that while free marketing works on the site, paid ads don't.

The automaker began re-evaluating its Facebook strategy earlier this year. According to the Wall Street Journal, General Motors determined that while free marketing works on the site, paid ads don't.

Read More:$10m-in-facebook-ads-saying-they-dont-work/
1374  Main Area and Open Discussion / Living Room / Dell apologizes for hiring sexist summit moderator on: May 15, 2012, 05:59:15 PM
Dell "sincerely apologizes" for offensive jokes by a moderator at its Copenhagen, Denmark, partner summit in April -- a few weeks later, and only on its Google+ page. Better than nothing, we suppose.

Dell's Google+ apology...find it here, and nowhere else!

Last week, I wrote about a Dell summit in Copenhagen, Denmark, where the moderator of the event, Mads Christensen, "entertained" the crowd of IT professionals with a barrage of sexist jokes, and exhorted them to go home and tell their wives to "shut up, bitch."

 This week, Dell posted an apology on its Google+ page, saying the company would be "more careful selecting speakers at Dell events."

Dell's Google+ apology...find it here, and nowhere else!

 The apology comes weeks after the actual event, unfortunately, after my column and tech blogger Christiane Vejlo's English-language post made it onto Reddit this past weekend. (Vejlo, the only journalist invited to the event, live-tweeted Christensen's comments as they happened, plus posted a follow-up in Danish and English.)

Read More:
1375  Main Area and Open Discussion / Living Room / AMD launches Trinity chipset to tackle Intel on: May 15, 2012, 05:55:12 PM
AMD, the processor manufacturer, has announced the new chipset that it hopes will rival Intel's Ivy Bridge processors.
The HP Envy Sleekbook will be powered by AMD's Trinity processor.

The new A-series chipsets, codenamed Trinity, will be used in thin and light laptops that will compete with Intel-backed ultrabooks, AMD says.

The company says Trinity-powered ultrathin laptops will be significantly cheaper than ultrabooks. The first to go on sale, in June, will be a 'Sleekbook' from Hewlett Packard.

Trinity will allow improved battery life for laptops because it can be set to draw around half the minimum power requirement of AMD's previous chipset, Llano.

Chris Cloran, corporate vice president of AMD, said: “Our 2nd-Generation AMD A-Series APU is a major step forward in every performance and power dimension, allowing users to enjoy a stunning experience without having to give up the things that matter to them most."

Intel will release its new Ivy Bridge chipset for ultrabooks next month. The current generation of ultrabooks, which began to go on sale at the end of last year, run on Sandy Bridge processors.

AMD's Trinity chipset will also be available for standard laptops and desktops. AMD claims that Trinity desktops have a 20-50 per cent better graphics performance for gamers than Intel's comparable Ivy Bridge processor.

Intel's Ivy Bridge processors measure just 22 nanometres across, which gives the potential for faster operations using less power. AMD's Trinity chipset, however, is still manufactured using the 32 nanometre process.

AMD says consumers care about performance and the overall experience, rather than the nanometre size of the processor.

Both Intel and AMD face growing competition from Arm, the Cambridge-based company that has so far dominated the mobile processor market.

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