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1376  Main Area and Open Discussion / Living Room / Cardigan Bay bottlenose dolphins 'learn factory whelk waste times for food' on: May 15, 2012, 06:35:05 PM
A school of bottlenose dolphins have figured out how to enjoy a free meal with the whelk waste from a seafood factory, marine researchers believe.

And like any school, there are also lessons for youngsters on how to do things properly.

Third year Swansea University marine biology student Jodie Denton counted how many bottlenose dolphins turned up after the licensed discharges by the plant at New Quay, Ceredigion.

She said: "There does seem to be a correlation between dolphin numbers and when the factory is open."

Cardigan Bay Marine Wildlife Centre (CBMWC) has identified 300 individual dolphins which use the bay, one of the largest in Europe and a location for sighting wildlife including seal, basking shark, minke whale and even Orca.

But it seems only the dolphins have cottoned on to the pickings to be had when Quay Fresh and Frozen Foods Ltd makes one of its discharges.

Read More:
1377  Main Area and Open Discussion / Living Room / Sea Shepherd founder Paul Watson faces extradition on: May 15, 2012, 06:34:22 PM
group Sea Shepherd, Paul Watson, has appeared in court in Germany.

The marine conservationist faces extradition to Costa Rica over charges arising from a clash with a ship that was fishing for sharks.

The confrontation occurred in 2002 in Guatemalan waters.

An official from the prosecutor's office said Mr Watson was accused of using his vessel to intimidate another, putting the crew at risk.

Guenter Wittig said Mr Watson was currently in temporary custody and a judge would decide whether to formally place him in detention pending extradition.

Sea Shepherd is a controversial direct action group best known for disrupting Japan's annual whale hunt.

In the past there have been collisions between its vessels and the whaling fleet, and its activists have also boarded Japanese vessels.
'Attempted murder'

The group said the German warrant related to an "alleged violation of ships traffic" which took place a decade ago when it "encountered an illegal shark finning operation" - referring to the practice of catching sharks, slicing off their valuable fins and returning the shark to the water where it will usually die.

On order of the Guatemalan authorities, the group says, it instructed the crew of the Costa Rican vessel in question, the Varadero, to head back to port to be prosecuted.

Read More:
1378  Main Area and Open Discussion / Living Room / Musicality test reveals UK's 'untapped talent' on: May 15, 2012, 06:33:46 PM
You might have more musical talent than you realise.

Results from a BBC experiment that tests musical skill suggest that many people who have not had formal training still have musical ability.

And talent is not influenced by age, sex or occupation either. The test indicated people from all walks of life underestimate their music potential.

Dr Daniel Mullensiefen of Goldsmiths College, who led the study, said some of the findings were surprising.

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1379  Main Area and Open Discussion / Living Room / Chile charges suspect with Japanese astronomer murder on: May 15, 2012, 06:33:10 PM
A Chilean man has been charged with the murder of Japanese astronomer Koichiro Morita in Santiago earlier this week.

Prof Morita, 57, was part of an international team involved in building the Alma radio telescope facility in northern Chile.

He was found collapsed outside his apartment in Santiago last Monday and died hours later in hospital.

Christopher Quijada, 25, is accused of killing him during a street robbery in the early hours of the morning.

Initially it was thought Prof Morita died as a result of an accidental fall, but an autopsy found he was struck on the head with a heavy object.

The authorities say Mr Quijada has confessed to tripping him over as he tried to escape being robbed, causing him to hit his head on the pavement, but denies murder.

The suspect will be held in custody while the investigation continues.

If convicted of robbery and homicide he faces a minimum of 10 years in jail.

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1380  Main Area and Open Discussion / Living Room / Asteroid Vesta is 'last of a kind' rock on: May 15, 2012, 06:32:51 PM
Vesta is the only remaining example of the original objects that came together to form the rocky planets, like Earth and Mars, some 4.6 billion years ago.

This assessment is based on data from the Dawn probe which has been orbiting the second largest body in the asteroid belt for the past 10 months.

The findings from the Nasa mission are reported in Science magazine.

They confirm that Vesta has a layered interior with a metal-rich core, just as Earth, Mars, Venus and Mercury do.

Using information about the shape of the asteroid and its gravity field, scientists can even say something about the likely size of this core.

The Dawn team calculates it to be about 220km (135 miles) across, representing about 40% of the radius of Vesta, or roughly 18% of its total mass.

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1381  Main Area and Open Discussion / Living Room / James Webb telescope's 'first light' instrument ready to ship on: May 15, 2012, 06:32:32 PM
One of Europe's main contributions to the James Webb Space Telescope (JWST) is built and ready to ship to the US.

The Mid-Infrared Instrument (Miri) will gather key data as the $9bn (£5.5bn) observatory seeks to identify the first starlight in the Universe.

The results of testing conducted at the Rutherford Appleton Laboratory in the UK have just been signed off, clearing Miri to travel to America.

James Webb - regarded as the successor to Hubble - is due to launch in 2018.

It will carry a 6.5m primary mirror (more than double the width of Hubble's main mirror), and a shield the size of a tennis court to guard its sensitive vision from the heat and strong light of our Sun.

The observatory has been tasked with tracking down the very first luminous objects in the cosmos - groupings of the first generation of stars to burst into life.

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1382  Main Area and Open Discussion / Living Room / Amber preserves insect pollen carriers on: May 15, 2012, 06:31:46 PM
What may be the earliest direct example of insect pollination has been identified by scientists.

The evidence is seen in 100-million-year-old amber blocks from Spain that include tiny invertebrates whose bodies are coated with pollen grains.

The role of insects in fertilising plants was one of the great steps in the evolution of life on Earth.

Today, most flowering plants, including many food crops, could not reproduce without the insect transport of pollen.

The discovery is reported in the American journal, the Proceedings of the National Academy of the Science (PNAS).

Amber, the fossilised remnant of tree resin, is a wonderful preservation medium, freezing in time the exquisite detail of insects that got caught up in the once sticky mess.

The translucent pieces described by the researchers in their PNAS paper come from the Basque Country.

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1383  Main Area and Open Discussion / Living Room / Airlines 'are conforming' with EU rules on emissions on: May 15, 2012, 06:31:29 PM
The vast majority of airlines have conformed with EU rules on reporting carbon dioxide emissions, the European Commission has said.

From next year, aircraft emissions will be included in the EU carbon market in an attempt to increase efficiency.

The EU required airlines to report by March on 2011 emissions as a "dry run"; all did, bar 10 from China and India.

The issue is controversial, with China telling airlines not to take part and US firms mounting a legal challenge.

Some commentators have suggested the outcome could be a full-scale trade war, even though the measure will add only about $3 to the price of a trans-Atlantic flight.

The EU has said it will suspend the requirement to include all flights beginning or ending in the EU in the Emission Trading Scheme (ETS) if other countries can agree a genuinely global mechanism that will charge airlines for the contribution they are making to global warming.

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1384  Main Area and Open Discussion / Living Room / Hen harriers 'being wiped out' by persecution on: May 15, 2012, 06:31:10 PM
Hen harriers are close to being wiped out as a breeding bird in England, with just one pair showing signs of nesting this year, a wildlife charity said.

The Royal Society for the Protection of Birds (RSPB) said none are trying to nest in Lancashire's Bowland Fells, their only recent English stronghold.

Only four nesting pairs raised chicks last year, all in Bowland.

The RSPB claim the bird has suffered from illegal persecution by gamekeepers on shooting estates.

It said the problem is particularly bad in areas with grouse moors, because the bird is a predator of the game bird.

The RSPB said last year's breeding in Bowland had been helped by landowner United Utilities, who tried to support the birds of prey on their estates.

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1385  Main Area and Open Discussion / Living Room / Work on Dounreay's Shaft to be sped up on: May 15, 2012, 06:30:32 PM
Plans to deal with one of the most controversial areas of the Dounreay nuclear site are to be accelerated.

Sunk in the 1950s close to the shores of the Pentland Firth, The Shaft plunges 65.4m (214.5ft) below ground.

It has been the subject of local legend, including the claim that one worker dropped his mother-in-law's ashes inside.

Radioactive waste was disposed there from 1959 to 1977, when an explosion ended the practice.

The new executive team at the nuclear complex in Caithness said work on the clean-up would be accelerated.

Swimming pool

In a presentation to staff and sub-contractors, it said there would be a "renewed emphasis" on The Shaft and another area called The Silo - which has been described as being like a swimming pool with a concrete roof.

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1386  Main Area and Open Discussion / Living Room / New Look at Prolonged Radiation Exposure: At Low... on: May 15, 2012, 06:28:16 PM
New Look at Prolonged Radiation Exposure: At Low Dose-Rate, Radiation Poses Little Risk to DNA, Study Suggests

A new study from MIT scientists suggests that the guidelines governments use to determine when to evacuate people following a nuclear accident may be too conservative.

The study, led by Bevin Engelward and Jacquelyn Yanch and published in the journal Environmental Health Perspectives, found that when mice were exposed to radiation doses about 400 times greater than background levels for five weeks, no DNA damage could be detected.

Current U.S. regulations require that residents of any area that reaches radiation levels eight times higher than background should be evacuated. However, the financial and emotional cost of such relocation may not be worthwhile, the researchers say.

"There are no data that say that's a dangerous level," says Yanch, a senior lecturer in MIT's Department of Nuclear Science and Engineering. "This paper shows that you could go 400 times higher than average background levels and you're still not detecting genetic damage. It could potentially have a big impact on tens if not hundreds of thousands of people in the vicinity of a nuclear powerplant accident or a nuclear bomb detonation, if we figure out just when we should evacuate and when it's OK to stay where we are."

Until now, very few studies have measured the effects of low doses of radiation delivered over a long period of time. This study is the first to measure the genetic damage seen at a level as low as 400 times background (0.0002 centigray per minute, or 105 cGy in a year).

"Almost all radiation studies are done with one quick hit of radiation. That would cause a totally different biological outcome compared to long-term conditions," says Engelward, an associate professor of biological engineering at MIT.

How much is too much?

Background radiation comes from cosmic radiation and natural radioactive isotopes in the environment. These sources add up to about 0.3 cGy per year per person, on average.

"Exposure to low-dose-rate radiation is natural, and some people may even say essential for life. The question is, how high does the rate need to get before we need to worry about ill effects on our health?" Yanch says.

Previous studies have shown that a radiation level of 10.5 cGy, the total dose used in this study, does produce DNA damage if given all at once. However, for this study, the researchers spread the dose out over five weeks, using radioactive iodine as a source. The radiation emitted by the radioactive iodine is similar to that emitted by the damaged Fukushima reactor in Japan.

Read More: http://www.sciencedaily.c.../2012/05/120515181256.htm
1387  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
1388  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
1389  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
1390  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
1391  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
1392  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
1393  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
1394  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
1395  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
1396  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
1397  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
1398  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
1399  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__
1400  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
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