Nuclear Radiation Affects Sex of Babies, Study Suggests

Ionizing radiation is not without danger to human populations. Indeed, exposure to nuclear radiation leads to an increase in male births relative to female births, according to a new study by Hagen Scherb and Kristina Voigt from the Helmholtz Zentrum München.

Their work shows that radiation from atomic bomb testing before the Partial Test Ban Treaty in 1963, the Chernobyl accident, and from living near nuclear facilities, has had a long-term negative effect on the ratio of male to female human births (sex odds). The research is published in the June issue of Springer's journal Environmental Science and Pollution Research.

Ionizing radiation from nuclear activity is known to have mutagenic properties and is therefore likely to have detrimental reproductive effects. It is thought that it may cause men to father more sons and mothers to give birth to more girls. Scherb and Voigt look at the long-term effects of radiation exposure on sex odds -- a unique genetic indicator that may reveal differences in seemingly normal as well as adverse pregnancy outcomes between maternal exposure and paternal exposure. In particular, they focus on sex odds data with respect to global atmospheric atomic bomb test fallout in Western Europe and the US, fallout due to nuclear accidents in the whole of Europe, and radioactive releases from nuclear facilities under normal operating conditions in Switzerland and Germany.

Their analyses show a significant male-female gap in all three cases:

• Increases in male births relative to female births in Europe and the US between 1964-1975 are a likely consequence of the globally emitted and dispersed atmospheric atomic bomb test fallout, prior to the test ban in 1963, that affected large human populations overall after a certain delay.
• There was a significant jump of sex odds in Europe in the year 1987 following Chernobyl, whereas no such similar effect was seen in the US, which was less exposed to the consequences of the catastrophe.
• Among populations living in the proximity of nuclear facilities (within 35km or 22 miles), the sex odds also increased significantly in both Germany and Switzerland during the running periods of those facilities.

Taken together these findings show a long-term, dose-dependent impact of radiation exposure on human sex odds, proving cause and effect. What is less clear is whether this increase in male births relative to female births is the result of a reduced frequency of female births or an increased number of male births. The authors estimate that the deficit of births and the number of stillborn or impaired children after the global releases of ionizing radiation amount to several millions globally.

Scherb and Voigt conclude: "Our results contribute to disproving the established and prevailing belief that radiation-induced hereditary effects have yet to be detected in human populations. We find strong evidence of an enhanced impairment of humankind's genetic pool by artificial ionizing radiation."

Nanoengineers Invent New Biomaterial That More Closely Mimics Human Tissue

A new biomaterial designed for repairing damaged human tissue doesn't wrinkle up when it is stretched. The invention from nanoengineers at the University of California, San Diego marks a significant breakthrough in tissue engineering because it more closely mimics the properties of native human tissue.

Shaochen Chen, professor in the Department of NanoEngineering at the UC San Diego Jacobs School of Engineering, hopes future tissue patches, which are used to repair damaged heart walls, blood vessels and skin, for example, will be more compatible with native human tissue than the patches available today. His findings were published in a recent issue of the journal Advanced Functional Materials.

The new biomaterial was created using a new biofabrication platform that Chen is developing under a four-year, $1.5 million grant from the National Institutes of Health. This biofabrication technique uses light, precisely controlled mirrors and a computer projection system -- shined on a solution of new cells and polymers -- to build three-dimensional scaffolds with well-defined patterns of any shape for tissue engineering.

"We are also exploring other opportunities," said Chen. "It's a new material. I think it's just a matter of time before more people will pick up and find applications for it in defense, energy and communications, for instance."

Although Chen's team is focused on creating biological materials, he said the manufacturing technology could be used to engineer many other kinds of materials including metal parts used in ships and spacecraft, for example.

Shape turned out to be essential to the new material's mechanical property. While most engineered tissue is layered in scaffolds that take the shape of circular or square holes, Chen's team created two new shapes called "reentrant honeycomb" and "cut missing rib." Both shapes exhibit the property of negative Poisson's ratio (i.e. not wrinkling when stretched) and maintain this property whether the tissue patch has one or multiple layers. One layer is double the thickness of a human hair, and the number of layers used in a tissue patch depends on the thickness of the native tissue that doctors are trying to repair. A single layer would not be thick enough to repair a heart wall or skin tissue, for example. The next phase of research will involve working with the Department of Bioengineering at the Jacobs School of Engineering to make tissue grafts to repair damaged blood vessels.

The team includes postdoctoral researchers in multiple disciplines: David Fozdar with the University of Texas at Austin, Department of Mechanical Engineering; Li-Hsin Han with the Stanford University School of Medicine, Department of Orthopeadic Surgery; and Pranav Soman and Jim Woo Lee at the UCSD Jacobs School of Engineering Department of NanoEngineering.

Drug May Help Overwrite Bad Memories

Recalling painful memories while under the influence of the drug metyrapone reduces the brain's ability to re-record the negative emotions associated with them, according to University of Montreal researchers at the Centre for Studies on Human Stress of Louis-H. Lafontaine Hospital. The team's study challenges the theory that memories cannot be modified once they are stored in the brain.

Metyrapone is a drug that significantly decreases the levels of cortisol, a stress hormone that is involved in memory recall," explained lead author Marie-France Marin. Manipulating cortisol close to the time of forming new memories can decrease the negative emotions that may be associated with them. "The results show that when we decrease stress hormone levels at the time of recall of a negative event, we can impair the memory for this negative event with a long-lasting effect," said Dr. Sonia Lupien, who directed the research.

Thirty-three men participated in the study, which involved learning a story composed of neutral and negative events. Three days later, they were divided into three groups -- participants in the first group received a single dose of metyrapone, the second received double, while the third were given placebo. They were then asked to remember the story. Their memory performance was then evaluated again four days later, once the drug had cleared out.. "We found that the men in the group who received two doses of metyrapone were impaired when retrieving the negative events of the story, while they showed no impairment recalling the neutral parts of the story," Marin explained. "We were surprised that the decreased memory of negative information was still present once cortisol levels had returned to normal."

The research offers hope to people suffering from syndromes such as post-traumatic stress disorder. "Our findings may help people deal with traumatic events by offering them the opportunity to 'write-over' the emotional part of their memories during therapy," Marin said. One major hurdle, however, is the fact that metyrapone is no longer commercially produced. Nevertheless, the findings are very promising in terms of future clinical treatments. "Other drugs also decrease cortisol levels, and further studies with these compounds will enable us to gain a better understanding of the brain mechanisms involved in the modulation of negative memories

Spitzer Sees Crystal 'Rain' in Outer Clouds of Infant Star

Tiny crystals of a green mineral called olivine are falling down like rain on a burgeoning star, according to observations from NASA's Spitzer Space Telescope.

This is the first time such crystals have been observed in the dusty clouds of gas that collapse around forming stars. Astronomers are still debating how the crystals got there, but the most likely culprits are jets of gas blasting away from the embryonic star.

"You need temperatures as hot as lava to make these crystals," said Tom Megeath of the University of Toledo in Ohio. He is the principal investigator of the research and the second author of a new study appearing in Astrophysical Journal Letters. "We propose that the crystals were cooked up near the surface of the forming star, then carried up into the surrounding cloud where temperatures are much colder, and ultimately fell down again like glitter."

Spitzer's infrared detectors spotted the crystal rain around a distant, sun-like embryonic star, or protostar, referred to as HOPS-68, in the constellation Orion.

The crystals are in the form of forsterite. They belong to the olivine family of silicate minerals and can be found everywhere from a periodot gemstone to the green sand beaches of Hawaii to remote galaxies. NASA's Stardust and Deep Impact missions both detected the crystals in their close-up studies of comets.

"If you could somehow transport yourself inside this protostar's collapsing gas cloud, it would be very dark," said Charles Poteet, lead author of the new study, also from the University of Toledo. "But the tiny crystals might catch whatever light is present, resulting in a green sparkle against a black, dusty backdrop."

Forsterite crystals were spotted before in the swirling, planet-forming disks that surround young stars. The discovery of the crystals in the outer collapsing cloud of a proto-star is surprising because of the cloud's colder temperatures, about minus 280 degrees Fahrenheit (minus 170 degrees Celsius). This led the team of astronomers to speculate the jets may in fact be transporting the cooked-up crystals to the chilly outer cloud.

The findings might also explain why comets, which form in the frigid outskirts of our solar system, contain the same type of crystals. Comets are born in regions where water is frozen, much colder than the searing temperatures needed to form the crystals, approximately 1,300 degrees Fahrenheit (700 degrees Celsius). The leading theory on how comets acquired the crystals is that materials in our young solar system mingled together in a planet-forming disk. In this scenario, materials that formed near the sun, such as the crystals, eventually migrated out to the outer, cooler regions of the solar system.

Poteet and his colleagues say this scenario could still be true but speculate that jets might have lifted crystals into the collapsing cloud of gas surrounding our early sun before raining onto the outer regions of our forming solar system. Eventually, the crystals would have been frozen into comets. The Herschel Space Observatory, a European Space Agency-led mission with important NASA contributions, also participated in the study by characterizing the forming star.

"Infrared telescopes such as Spitzer and now Herschel are providing an exciting picture of how all the ingredients of the cosmic stew that makes planetary systems are blended together," said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington.

The Spitzer observations were made before it used up its liquid coolant in May 2009 and began its warm mission.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the Spitzer Space Telescope mission for the agency's Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

Astronomers Unveil Most Complete 3-D Map of Local Universe

Astronomers have unveiled the most complete 3-D map of the local universe (out to a distance of 380 million light-years) ever created. Taking more than 10 years to complete, the 2MASS Redshift Survey (2MRS) also is notable for extending closer to the Galactic plane than previous surveys -- a region that's generally obscured by dust.

Karen Masters (University of Portsmouth, UK) presented the new map May 25, 2011 in a press conference at the 218th meeting of the American Astronomical Society.

"The 2MASS Redshift Survey is a wonderfully complete new look at the local universe -- particularly near the Galactic plane," Masters said. "We're also honoring the legacy of the late John Huchra, an astronomer at the Harvard-Smithsonian Center for Astrophysics, who was a guiding force behind this and earlier galaxy redshift surveys."

A galaxy's light is redshifted, or stretched to longer wavelengths, by the expansion of the universe. The farther the galaxy, the greater its redshift, so redshift measurements yield galaxy distances -- the vital third dimension in a 3-D map.

2MRS chose galaxies to map from images made by the Two-Micron All-SkySurvey (2MASS). This survey scanned the entire sky in three near-infrared wavelength bands. Near-infrared light penetrates intervening dust better than visible light, allowing astronomers to see more of the sky. But without adding redshifts, 2MASS makes only a 2-D image. Some of the galaxies mapped had previously-measured redshifts, and Huchra started painstakingly measuring redshifts for the others in the late 1990s using mainly two telescopes: one at the Fred Lawrence Whipple Observatory on Mt. Hopkins, AZ, and one at the Cerro Tololo Inter-American Observatory in Chile. The last observations were completed by 2MRS observers on these telescopes shortly after Huchra's death in October 2010.

Robert Kirshner, Huchra's colleague at the Center for Astrophysics (CfA), said, "John loved doing redshift surveys and he loved the infrared. He had the insight to tell when infrared technology, formerly the province of the experts, was ripe for routine use in a big project."

"John was instrumental in setting up the 2MASS telescope at Mount Hopkins, seeing the infrared side of the project through, and making a much more complete survey of the local universe. It's a wonderful tribute to John that his colleagues have finished the infrared-selected galaxy redshift survey that John started," he added.

The 2MRS mapped in detail areas previously hidden behind our Milky Way to better understand the impact they have on our motion. The motion of the Milky Way with respect to the rest of the universe has been a puzzle ever since astronomers were first able to measure it and found it couldn't be explained by the gravitational attraction from any visible matter. Massive local structures, like the Hydra-Centaurus region (the "Great Attractor") were previously hidden almost behind the Milky Way but are now shown in great detail by 2MRS.

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.

Students Struggling With Math May Have a Neurocognitive Disorder Called Dyscalculia: Disorder Affects Roughly as Many People as Dyslexia

Students who struggle to learn mathematics may have a neurocognitive disorder that inhibits the acquisition of basic numerical and arithmetic concepts, according to a new paper. Specialised teaching for individuals with dyscalculia, the mathematical equivalent of dyslexia, should be made widely available in mainstream education, according to a review of current research published in the journal Science.

Science can't design away tornadoes' deadly threat

WASHINGTON – Storm science has greatly improved tornado warnings in recent years. But if that's led anyone into a sense of security, that feeling has taken a beating in recent weeks.

Super Outbreak 2011, on April 25-28, killed more than 300 people in the South and Midwest. Less than a month later, a devastating tornado took more than 130 lives around Joplin, Mo. This is now the deadliest year for tornadoes since 1950, based on an assessment of National Weather Service figures.

This despite warnings of as much as 20 minutes, thanks to improved weather radar installed across the country in the 1990s. Before that, tornado warnings often weren't issued until a twister was sighted on the ground.

Scientists see a variety of factors that helped make this year's twisters deadlier — from La Nina to public complacency, from global warming to urban sprawl.

"We thought for the longest time physical science could get us by ... that we could design out of disaster," said meteorology professor Walker Ashley of Northern Illinois University. Now scientists are finding they need to take human nature into account.

What is clear is that certain factors add to the risk of death. The most vulnerable folks are those living in mobile homes and houses without basements. For a variety of reasons, a lot of homes don't have basements.

Twisters occurring on weekends — like the Joplin tornado — and at night tend to be greater killers because they catch people at home. At night, twisters are harder to see and sleeping people may not hear a warning.

Those less likely to be killed in a storm tend to be more educated and to have a plan in place beforehand.

In Sedalia, Mo., 30-year-old Sean McCabe had the right idea when the tornado struck, heading to the basement. He said the storm shoved him down the final flight of steps. He had scrapes and cuts on his hands, wrists, back and feet. Blood was visible in the house, and much of the roof of the house was gone.

"I saw little debris and then I saw big debris, and I'm like OK, let's go," said McCabe.

Having a plan was a lifesaver for Tuscaloosa's LaRocca Nursing Home in Alabama. As the storm howled, four dozen residents massed in the hallways as trees crashed down and a cloud of dust rained upon them. When the dust settled, the staff realized their drills had paid off. Not one patient was killed, and the worst injury among them was a bruise.

Hundreds have not been so lucky, with more than 500 deaths and counting so far this year, a toll not seen in more than a half-century.

The toll for 2011 is now at least 520 people, exceeding the previous highest recorded death toll in a single year of 519 in 1953. There were deadlier storms before 1950, but those counts were based on estimates and not on precise figures.

The National Weather Service said 58 tornadoes touched down in Alabama on April 27, killing 238 people in that state alone and injuring thousands. Scores died in other states from twisters spawned by the same storm system. Put together, emergency management officials say the twisters left a path of destruction 10 miles wide and 610 miles long, or about as far as a drive from Birmingham to Columbus, Ohio.

Statewide, Alabama officials estimate there was enough debris to stack a football field a mile high with rubble.

Contributing to the massive loss of life is the growth of urban areas, suggested Marshall Shepherd, a professor of atmospheric science at the University of Georgia.

"Historically, the central business districts of cities have not been hit that frequently," he explained. But as you increase the land area covered by homes and businesses, he said, "you're increasing the size of the dartboard."

An expanding population does increase exposure to the danger, agreed Ashley, who fears deaths could begin to rise in the future as a result of sprawl and more people living in vulnerable residences such as mobile homes.

If the Tuscaloosa and Joplin tornadoes had each been a few miles to the south, on farmland, little would be heard about them, Ashley said, but when extremely violent tornadoes mingle with urban sprawl "you're going to have a disaster."

"I hope this will be an outlier year, very much like Katrina was to hurricanes," he said in a telephone interview from a field trip to chase tornadoes.

But no one can guarantee that, and weather experts are becoming increasingly concerned about how people respond to tornado warnings.

"A lot of it is complacency," Ashley said. "The population seems to be becoming desensitized to nature. I don't know why."

Studies have shown that 15 to 20 minutes is the most effective amount of warning time, and longer warning times can increase deaths. Weather experts aren't sure why, but worry that people think that if a twister hasn't appeared in a certain amount of time, it must have been a false alarm.

Yet a long-track tornado can be on the ground for 30 miles.

"If you have a basement, you don't need 20 minutes warning, but if you are in a mobile home park you may need more than 20 minutes to find a shelter," commented Alan W. Black, a University of Georgia doctoral student and co-author with Ashley of a recent study of tornado and wind fatalities.

Jerry Brotzge, a research scientist at the Center for Analysis & Prediction of Storms, University of Oklahoma, said many people who hear warnings will look outside to see if they can see the tornado — "they need some kind of confirmation, they want to see it."

But the Joplin tornado was at least partly rain-wrapped, meaning that a powerful rainstorm obscured it from some directions and "they wouldn't have seen it coming."

"Even when people are sheltered in their homes, if they are not underground they can die," Brotzge added.

But asking people to evacuate an area is also a difficult decision, he said, "what if you have a traffic jam and the tornado hits that."

Ashley concluded: "The take-home is, people have to take personal responsibility for their lives."

Why there have been so many tornado threats this year is harder to say.

Viewing pictures of the tornado aftermath it's hard to overestimate the power of such storms, and records bear out how strong they can be.

"You see pictures of World War II, the devastation and all that with the bombing. That's really what it looked like," said Kerry Sachetta, the principal of a flattened Joplin High School. "I couldn't even make out the side of the building. It was total devastation in my view. I just couldn't believe what I saw."

And that movie image a few years ago was no joke: A cow was transported 10 miles by a twister in Iowa in 1878 and a tornado in Minnesota moved a headstone three miles in 1886.

One Joplin resident said a picture that was sucked off his house's wall was found in Springfield, 70 miles away. An insurance policy was found more than 40 miles from its original residence in Oklahoma in 1957 and a 210-mile trip was taken by a canceled check in Nebraska in 1915, according to a study several years ago by researchers at the University of Oklahoma and St. Louis University.

Typically, tornadoes spawn in the clash between warm, moist air from the Gulf of Mexico and cooler, dry air from the north and west — conditions that mark Tornado Alley in the Midwest and South, the most common breeding grounds for twisters.

Factors in this year's excess may include La Nina, a periodic cooling of the tropical Pacific Ocean which can affect weather worldwide. In a La Nina year there tend to be more tornadoes than average. If that is a factor, the good news is that La Nina is weakening and is expected to end in a month or so.

The meandering jet stream high in the atmosphere that directs the movements of weather also has been in a pattern that encourages warm Gulf air to move in and clash with drier air masses.

While studies of global warming have suggested it could cause more and stronger storms, National Weather Service Director Jack Hayes isn't ready to blame climate change — at least not yet — saying it's too soon to link individual events with the ongoing warming.

Tornado researcher Howard B. Bluestein of the University of Oklahoma says his best guess is this unusual outburst of twisters is due to natural variability of the weather.

"Sometimes you get a weather pattern in which the ingredients for a tornado are there over a wide area and persist for a long time. That's what we're having this year," he said.

"If we see this happen next year and the following year and the following year," then maybe climate change could be to blame, he said.

Whatever the reasons it's an extraordinary year for tornadoes and the worst may not be over. May is usually the peak month, but June traditionally gets lots of twisters, and they can occur in any month.

"You can never completely breathe easy," concluded Russell Schneider, director of the government's Storm Prediction Center in Norman, Okla.

Astronauts pack up on next-to-last shuttle flight

CAPE CANAVERAL, Fla. – Endeavour's astronauts took care of some last-minute space station chores Saturday before packing up to come home and end the next-to-last shuttle flight.

The space shuttle and its crew of six will depart the International Space Station late Sunday night. They worked to repair one of the space station's air purifiers and straightened out the suits that were used in four spacewalks. The final spacewalk of the mission, on Friday, completed the U.S. portion of station construction.

Now that the spacewalks are over, Mission Control told the astronauts they "can bask in the glow of a job well done."

Shuttle pilot Gregory Johnson said it will be bittersweet to leave. He and his crewmates installed a $2 billion physics experiment at the orbiting outpost, as well as an extension pole and a platform full of spare parts.

"It's been a fantastic mission," Johnson said in a series of news interviews. "It's the sort of mission that astronauts dream of having."

Johnson said he and his colleagues are spending their final hours at the space station doing "everything we can do to help the space station out before we return to Earth." The station is so big now, he said, that sometimes he takes a wrong turn and finds himself in the wrong chamber.

Endeavour is scheduled to return to Florida before dawn Wednesday, 16 days after blasting off.

After Sunday night's undocking, Johnson will guide Endeavour through a victory lap around the space station. He said he'll try to maintain a good position for the shuttle, "so we can get great photos of one of the final fly-arounds of the space station." The shuttle crew also will test out an experimental navigation system for future spacecraft.

This is the final voyage of Endeavour, the youngest in the shuttle fleet. NASA is closing down the shuttle program this summer after 30 years. Atlantis will fly one last time to the space station in July.

Birthplace of 'hot Neptunes' revealed

HOT Neptunes are modestly giant planets that resemble their namesake but orbit close to their stars. But the puzzle is why we see so many hot Neptunes elsewhere but none in our solar system.

The conventional view is that these worlds formed in cold regions far from their stars and then migrated inwards. Now Brad Hansen at the University of California, Los Angeles, and Norm Murray of the Canadian Institute for Theoretical Astrophysics in Toronto say hot Neptunes may have arisen right where they are.

The team modelled a disc of gas and dust around a young star. In work submitted to The Astrophysical Journal, they suggest that if the disc is particularly massive, large cores can form in the inner regions with enough gravity to attract gas, producing hot Neptunes (arxiv.org/abs/1105.2050). However, our sun's disc of gas and dust lacked the mass to build giant worlds in its inner regions. So our Neptune formed far from the sun.

This scenario may explain the large number of hot Neptunes orbiting other stars, says Gregory Laughlin at the University of California, Santa Cruz.

X-ray video reveals how dogs drink

Dogs don't have cheeks to trap liquid, so how do they manage to drink? Alfred Crompton and his team from Harvard University fed a dog some dark broth to observe the process, followed by X-ray video to reveal details of the tongue action.

A recent study showed that cats drink by drawing milk upwards as it clings to the tip of their tongue. Although dogs have a similarly-shaped mouth, it was suggested that unlike cats, they curl their tongues backwards and scoop up liquid.

Crompton's analysis proved that this isn't the case: cats and dogs use the same basic mechanism to lift liquid into their mouths. Although X-ray footage did show that a tiny depression forms on the back surface of a dog's tongue as it lifts up a column of milk, the scooped-up liquid simply spilled out of its mouth. So dogs are simply messier drinkers than cats.

Another difference is that dogs trap milk in tiny folds on the roof of their mouth between sips, allowing them to reach for more milk without losing the previous drops. But even so, it took this dog three laps to finish the contents of a bowl. Drinking just isn't as easy as it seems.

Reindeer gained UV vision after moving to the Arctic by Jessica Griggs

Reindeer see their world in glorious ultraviolet, helping them find food and avoid predators.

Most mammals, including humans, see using light from the visible part of the spectrum; ultraviolet light, which has a shorter wavelength, is invisible. But not so reindeer, says Glen Jeffery of University College London.

The frozen wastes of the Arctic reflect around 90 per cent of the UV light that hits them; snow-free land typically reflects only a few per cent. So Jeffery and colleagues wondered whether reindeers had adapted to their UV-rich world.

In dark conditions, they shone LED lights of different wavelengths, including UV, into the eyes of 18 anaesthetised reindeers while recording with an electrode whether nerves in the eye fired, indicating that the light had been seen. The UV light triggered a response in the eyes of all the reindeer.

"Since migrating to the Arctic 10,000 years ago, these animals have adapted incredibly quickly," says Jeffery.

Finding food

The team's experiments with a UV camera in the Arctic suggest why. They showed that urine – a sign of predators or potential mates – and lichens – a major food source for reindeers in the winter months – absorb UV light, making them appear black in contrast to the UV-reflecting snow.

"Very few mammals see UV light. Rodents do and some species of bat do but we have no idea why they have developed this capability," says Jeffery. "This is the first time we have got a real handle on why a mammal uses UV light."

The eyes of most mammals cannot cope with UV light because it carries enough energy to destroy their sensitive photoreceptors, permanently damaging vision. To prevent this happening we experience "snow blindness": our corneas respond to UV light by becoming temporarily cloudy, preventing excess amounts of UV reaching and burning the retina.

"Why don't reindeer, arctic fox, polar bears or arctic seals get snow blindness?" asks Jeffery. "Arctic mammals must have a completely different mechanism for protecting their retinas."

To try to shed light on this conundrum, Jeffery and his team plan to return to the Arctic later in the year. "If we could work out what this protective mechanism is perhaps we could learn from it and develop new strategies to prevent or treat the damage UV can cause to humans," he says.

Journal reference: Journal of Experimental Biology, DOI: 10.1242/jeb.053553

Land speed record bid could make space flight safer

The team that hopes to break the world land speed record in a rocket-assisted jet car could create an important spin-off for the nascent space tourism market: a safer rocket engine.

So says Daniel Jubb, who is the founder of military rocket motor company Falcon Project Limited (FPL), based in Mojave, California, and chief rocket engineer for the Bloodhound SuperSonic Car, which aims to reach a speed of 1600 kilometres per hour (1000 miles per hour) on the salt flats in Hakskeen Pan, South Africa, sometime in 2013. The current record is 1227 km/h, and was set in 1997 by the Bloodhound team's driver Andy Green, in a car called Thrust SSC.

Bloodhound SSC looks like a wingless aircraft and will be powered by an engine from a Eurofighter Typhoon fighter jet as well as a hybrid liquid/solid fuel rocket motor designed by FPL. To keep the rocket fed with fuel, the vehicle uses a Cosworth Formula 1 racing car engine as a fuel pump.

Atlas profiles crash-course galaxies

A new atlas combining ultraviolet and infrared images from the Spitzer telescope and Galaxy Evolution Explorer (GALEX) spacecraft captures colliding galaxies from start to finish. Lauranne Lanz of the Harvard-Smithsonian Center for Astrophysics unveiled the findings at the American Astronomical Society meeting in Boston on Wednesday. The images provide a better understanding of what could happen when our galaxy collides with the Andromeda galaxy five billion years from now.

When two galaxies merge into a larger one, the destruction gives rise to cosmic clouds of gas and dust that become star nurseries. This galactic train wreck transpires over the course of millions to billions of years, making astronomers dependent on an assortment of examples for a complete picture.

Pictured above, the twin spiral galaxies NGC 935 and IC 1801 begin to collide. GALEX ultraviolet emission shows young hot stars in blue while Spitzer illuminates heated dust in red. The different qualities these wavelengths highlight provide rich data for researchers.

Report on Air France 447 crash deepens mystery

Paul Marks, senior technology correspondent

The mystery surrounding the crash of Air France flight 447 in June 2009 deepened today when a preliminary report from air crash investigators revealed a double failure of the plane's speed sensors - critical for fly-by-wire computer-assisted flight - followed by the flight crew inexplicably failing to maintain airspeed and deal with the stall that resulted.

The BEA says the plane hit turbulence at cruise altitude and then suffered temporary failures of two speed sensors - possibly due to high altitude icing. Because this meant an agreed speed reading could not be calculated - and speed is critical for maintaining aerodynamic lift - the flight computer switched off the autopilot and handed control to the pilots.

The nonflying pilot was heard confirming this disengagement had happened on the cockpit voice recorder saying: "so, we've lost the speeds," and then "alternate law". Fly-by-wire flight, where the plane is kept straight and level and at a safe lift-producing speed by a computer program (which has four backups) is managing flight in what is called "normal law". This also ensures the plane can only bite into the airflow at a low, lift-producing "angle of attack".

When the pilots are in charge the plane is said to be obeying "alternate law" - but here the angle of attack is not computer managed.

As control was handed over the stall warning sounded, yet the pilot flying the plane decided to climb. A stall usually requires the nose to be dipped downward to gain airspeed and regain the missing lift. Yet AF447 climbed inexorably to its ceiling of 38,000 feet at a very high angle of attack of more than 35 degrees. With the stall warning sounding, the nose remained tipped upward. The plane stalled, losing altitude at 11,000 feet per minute. It fell for 3 minutes 30 seconds when it hit the water nose up 16-degrees and belly first - just as the BEA had predicted from their analysis of floating wreckage.

This is the second time in recent memory that a flight has suffered from a nose up situation in a stall. Colgan Air lost an aircraft near Buffalo, New York, in February 2009 when drag caused by thick icing slowed a commuter flight so much it stalled. The pilot in that case also adopted a nose up attitude. It is not what pilots are trained to do.

Contributors to the online Professional Pilot's Rumour Network - Pprune - are astonished that the AF447 pilots maintained a nose-up attitude. You can read their comments on (and either side of) this thread page. Some wonder if cockpits are being over-computerised leaving pilots baffled when it comes to manual flight in an emergency.

Others are worried about crew workload, coping with a blizzard of alarms in a thunderstorm in the dead of night. Mostly, they are so surprised the pilot kept the nose up in a stall - and for so long - that they think there has to be more to it: did other instruments fail?

The investigation continues.

Adult Skin Cells Converted Directly to Beating Heart Cells

Scripps Research Institute scientists have converted adult skin cells directly into beating heart cells efficiently without having to first go through the laborious process of generating embryonic-like stem cells. The powerful general technology platform could lead to new treatments for a range of diseases and injuries involving cell loss or damage, such as heart disease, Parkinson's, and Alzheimer's disease.

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Human skin cells can be converted directly into functional neurons in a period of four to five weeks with the addition of just four proteins, according to a study by researchers at the Stanford University School of Medicine. The finding is significant because it bypasses the need to first create induced pluripotent stem cells, and may make it much easier to generate patient- or disease-specific neurons for study in a laboratory dish.

Green and Lean: Secreting Bacteria Eliminate Cost Barriers for Renewable Biofuel Production

A Biodesign Institute at Arizona State University research team has developed a process that removes a key obstacle to producing low-cost, renewable biofuels from bacteria. The team has reprogrammed photosynthetic microbes to secrete high-energy fats, making byproduct recovery and conversion to biofuels easier and potentially more commercially viable.

Book of Fungi Makes Us Want to Go Mushroom-Hunting

The new Book of Fungi, by Peter Roberts and Shelley Evans, is a couple of kilograms worth of beautiful mushroom book. The lurid photographs and enticing, offhandedly witty descriptions make the reader want to go out collecting specimens right away -- but the hardcover book's glaring flaw is that, with actual-size glossy pictures of 600 species of fungus, it's hardly a portable companion to the wonders of the woods.

Slow-Motion X-Ray Video Reveals the Slurpy Mechanics of Dogs' Drinking

It’s amazing what you can learn with a high-frame-rate X-ray camera, a cup of beef broth, and a Portuguese water dog. For instance, we knew that dogs are obnoxious drinkers, but we didn’t realize that rather than scooping liquids into their mouths with the undersides of their tongues, they actually tap a trick of fluid mechanics--just as cats do--to pull columns of water from the water bowl into their mouths.

Thanks to evolutionary biologist Alfred Crompton and some Harvard colleagues, now we know. Crompton’s study of the mechanics of canine drinking published today in the Journal of the Royal Society Biology Letters, and included are the videos seen above and, in X-ray, below. The videos and complementing study show that, contrary to conventional thought on the matter, dogs drink exactly like cats.

While dogs do pick up a certain amount of water by curling the undersides of their tongues, most of that ends up back in the bowl (or elsewhere). Rather, the flattened tongue barely nicks the surface of the water before snapping back, and when it does so it manages to pull a column of liquid into the air behind it--a column that the canine can then bite down on almost as it would a solid.

It actually takes three or four laps for the dog to work the water along its tongue and the roof of its mouth and into the throat. Which might explain why it seems like that last lap always ends up all over the floor.

UPS's Prototype Plastic Delivery Trucks Reduce Weight and Increase Mileage

Electric cars might be the future, but for some uses, like the demands of a delivery truck, they just don't have the power or range quite yet. But that doesn't mean giving up and using inefficient materials and construction while waiting for the electric revolution to come. UPS is testing out prototype plastic trucks that reduce the usual truck weight by 1,000 pounds, increase the mileage by up to 40%, and are even more easily serviced.

The trucks are constructed from ABS plastic, a lightweight and rugged material that reduces the weight of these vehicles by around 1,000 pounds, compared to the usual sheet metal. Trucks of this size typically weigh around five tons, depending on the packages being delivered. The plastic body has a few other benefits as well. Painted sheet metal is both heavy (the paint alone can weigh about 100 pounds!) and fragile--a slight dent or nick makes the metal beneath the paint visible, at which point UPS has to service the truck to keep it looking fresh. But this plastic is brown all the way through, so it can suffer dents without looking mangled.

There are a few other thoughtful elements to the new design, like switching all lights (besides headlights, for some reason) to more efficient LEDs, and a nearly modular design that allows for various parts (bumpers, side panels) to be replaced easily, quickly, and cheaply. Those adjustments make the new truck efficient enough that the typical 200-hp engine could be replaced with a sprightly 150-hp engine without losing power.

The important thing here is that this prototype is actually cost-effective, right now. It's not as exciting an advancement as, say, a fleet of hydrogen-powered trucks or cars made of hemp, but unlike a fleet of hydrogen-powered trucks, there's a legitimate chance of immediate adoption. The prototypes are undergoing testing this year, and provided they're found road-worthy, could start hitting the road in 2012.

The Facts and Fiction of Tornadoes

Extraordinarily bad, even by historical standards. The death toll, now at more than 480, is the highest since 1953, when an outbreak of twisters across the Midwest and the Northeast claimed 519 lives. The high death toll this year is all the more remarkable considering that early warning systems are in place throughout tornado country, made possible by the advent of Doppler radar. Many tornado experts believed that the advances in technology had greatly diminished the risk of mass tornado fatalities.

“We never thought there’d be another year of deaths like this, with all our warning systems,” said Thomas P. Grazulis, a tornado historian.

Since 1875, there have been just 15 years with more than 360 tornado deaths, and none since 1975. The single deadliest tornado year in the United States was 1925, with 794 fatalities. This year now ranks eighth on the list of deadliest tornado years.

The tornado that struck Joplin, Mo., on Sunday, with its death toll now standing at 122, is the deadliest since the National Oceanic and Atmospheric Administration began keeping records in 1950.

Fossil Extends Life Span of a Marine Predator

The largest animal species of the Cambrian period, a marine predator with a long, segmented body and a pair of grasping appendages, lived much longer than previously thought and grew to sizes much larger than previously known.The animals, known as anomalocaridids, were thought to have gone extinct after the Cambrian period, 540 million to 500 million years ago. Now a newly discovered specimen indicates that they actually lived another 30 million years, into the Early Ordovician period.

The new specimen measures more than three feet in length; the biggest specimen previously known was about two feet long.

Derek Briggs, a paleontologist at Yale, and Peter Van Roy, a paleontologist at Ghent University in Belgium, discovered the specimen in southeastern Morocco and describe their findings in the current issue of the journal Nature.

Along with the anomalocaridid, the pair also discovered more than 1,500 fossils of other soft-bodied marine animals, including sponges, horseshoe crabs and tube-dwelling worms, at the site.

Generally, soft-bodied animals do not preserve as well as hard-shelled animals, making intact fossils a rare find. The find in Morocco was unique because the fossils were trapped in sediment clouds that preserved the bodies extremely well, Dr. Briggs said.

When anomalocaridids were first described, in the late 1800s, their scaly appendages had been found in isolation and were incorrectly thought to be the legs of a shrimp species. The animal’s disclike head was also found in isolation, and some believed it might be a jellyfish.

A century later, in 1985, Dr. Briggs published a paper that correctly described the whole animal for the first time.

New Mileage Stickers Include Greenhouse Gas Data

The new labels, which replace a five-year-old design that provided only basic information about estimated fuel economy, represent the broadest overhaul in the sticker program’s 35-year history. There will be different labels for conventional vehicles, plug-in hybrids and all-electric vehicles, with cars running solely on battery power estimated to get 99 miles per gallon.

The Environmental Protection Agency and the Department of Transportation, which are jointly responsible for the window sticker program, rejected a radically different design that would have prominently displayed a letter grade from A to D comparing a given vehicle’s fuel economy and air pollution to those of the entire fleet of new cars.

Automakers objected to that sticker as simplistic and potentially misleading. The government instead adopted a much busier label with more information and a sliding scale comparing vehicles across classes.

“These labels will provide consumers with up-front information about a vehicle’s fuel costs and savings so that they can make informed decisions when purchasing a new car,” said Ray LaHood, the transportation secretary.

The new stickers will for the first time include a greenhouse gas rating, comparing a vehicle’s emissions of carbon dioxide and other heat-trapping gases with those of all other vehicles, as well as a smog rating based on emissions of other air pollutants like nitrogen oxide and particulates.

Cars capable of running on electricity will get the highest greenhouse gas and smog ratings, but the fine print indicates that the measure does not take into account emissions from power plants generating the electricity used to charge them up. Stickers for plug-in hybrids and electric cars will also include their charging time and estimated range while running in electric-only mode.

Black holes spinning faster and faster, researchers say

The gi­ant black holes in the cen­ters of ga­lax­ies are spin­ning faster than ev­er be­fore on av­er­age, two U.K. as­tro­no­mers have con­clud­ed based on tel­e­scope ob­serva­t­ions.

Alejo Martinez-Sansigre of the Uni­vers­ity of Ports­mouth and Steve Raw­lings of the Uni­vers­ity of Ox­ford are re­port­ing the find­ings in the jour­nal Monthly No­tices of the Roy­al As­tro­nom­i­cal So­ci­e­ty.

Sci­en­tists be­lieve most ga­lax­ies har­bor at their cen­ters huge, “su­per­mas­sive” black holes that weigh the equiv­a­lent of a mil­lion to a bil­lion times our sun. Black holes are ob­jects so dense and heavy that their gra­vity sucks in an­y­thing that strays too close, even light rays. While black holes can’t be seen di­rect­ly, it’s pos­si­ble to see the ma­te­ri­al that’s grad­u­ally fall­ing in­to a black hole. Usu­ally spi­ral­ing in­ward and form­ing a disk shape around the cen­tral mass, the ma­te­ri­al can be­come very hot and emit radia­t­ion in­clud­ing X-rays de­tect­a­ble by space-based tel­e­scopes. Ra­di­o waves are al­so emitted, de­tect­a­ble from ground tel­e­scopes.

Twin jets of par­t­i­cles of­ten spray out and away from black holes and their “ac­cre­tion disks.” How these jets arise is un­clear, but a ma­jor fac­tor is thought to be that black holes are spin­ning. Phys­i­cists have thus been try­ing to learn more in­forma­t­ion about black hole spins, in­clud­ing how these might be chang­ing.

The spin of black holes can al­so “tell you a lot about how they formed,” Mar­tinez-San­sigre said. “Our re­sults sug­gest that in re­cent times a large frac­tion of the most mas­sive black holes have some­how spun up. A likely ex­plana­t­ion is that they have merged with oth­er black holes of si­m­i­lar mass, which is a truly spec­tac­u­lar event, and the end prod­uct of this merg­er is a faster-spin­ning black hole.”

Mar­tinez-San­sigre and Raw­lings com­pared the­o­ret­i­cal mod­els of spin­ning black holes with tel­e­scope ob­serva­t­ions us­ing ra­di­o, X-ray and visible-light da­ta. They con­clud­ed that ex­ist­ing the­o­ries can ex­plain the popula­t­ion of su­per­mas­sive black holes with jets.

Us­ing ra­di­o ob­serva­t­ions, the as­tro­no­mers sam­pled the popula­t­ion of black holes, de­duc­ing the spread of the pow­er of the jets. By es­ti­mat­ing how fast they draw in ma­te­ri­al, the re­search­ers could then in­fer how quickly these ob­jects are spin­ning. The spins could then be com­pared at dif­fer­ent times in the un­iverse, be­cause as­tro­no­mers can get a look at ear­li­er pe­ri­ods simply by look­ing fur­ther away. This works be­cause the light from more dis­tant ob­jects takes long­er to reach us, re­veal­ing them as they ap­peared in a more dis­tant past.

“Later this dec­ade we hope to test our idea that these su­per­mas­sive black holes have been set spin­ning rel­a­tively re­cently,” Raw­lings said. “Black hole merg­ers cause pre­dict­a­ble dis­tor­tions in space and time—so-called gravita­t­ional waves. With so many col­li­sions, we ex­pect there to be a cos­mic back­ground of gravita­t­ional waves.” This in turn should “change the tim­ing of the pulses of ra­di­o waves that we de­tect from the rem­nants of mas­sive stars known as pul­sars,” he added. “If we are right, this tim­ing change should be pick­ed up by the Square Kil­o­me­tre Ar­ray, the gi­ant ra­di­o ob­servatory due to start op­er­at­ing in 2019.”

NASA to Launch New Science Mission to Asteroid in 2016

This is a critical step in meeting the objectives outlined by President Obama to extend our reach beyond low-Earth orbit and explore into deep space," said NASA Administrator Charlie Bolden. "It's robotic missions like these that will pave the way for future human space missions to an asteroid and other deep space destinations."

NASA selected OSIRIS-REx after reviewing three concept study reports for new scientific missions, which also included a sample return mission from the far side of the moon and a mission to the surface of Venus.

Asteroids are leftovers formed from the cloud of gas and dust -- the solar nebula -- that collapsed to form our sun and the planets about 4.5 billion years ago. As such, they contain the original material from the solar nebula, which can tell us about the conditions of our solar system's birth.

Prostate Cancer Drug Zytiga May Extend Life !

The newly approved prostate cancer pill Zytiga (abiraterone acetate) may extend life by up to four months in men with spreading cancer who have already been treated with chemotherapy, a study shows.

This survival gain "means quite a bit," says study researcher Howard I. Scher, MD, chief of the genitourinary oncology service at Memorial Sloan-Kettering Cancer Center in New York City. "These are a group of patients for whom there is no standard of care and it is particularly gratifying to see these results, to say the least."

The new study is published in the New England Journal of Medicine.

Prostate cancer is the most common cancer diagnosed in men besides skin cancer, according to the American Cancer Society. One out of every six men will be diagnosed with prostate cancer during his lifetime.

The new drug, which was approved by the FDA in April, inhibits a protein that helps form male hormones. The findings may help reshape the way doctors view and treat advanced prostate cancer.

The new study included 1,195 men with metastatic prostate cancer whose disease had progressed after chemotherapy. Those men who received steroid therapy along with the new pill survived for 14.8 months, on average, compared with 10.9 months seen among those who received a placebo along with steroids. This translated into a 34% reduction in risk of dying, the study shows.

This survival edge was considered so significant that men who received the placebo were permitted to switch to the new drug before the study was completed.

Men who took the new pill also saw greater responses in levels of prostate-specific antigen (PSA) than men who received placebo. Elevated levels of PSA may be a marker for prostate cancer.

The men who took Zytiga also showed improvements in disease-related symptoms and prostate cancer progression on imaging tests compared with men who received the placebo.

Zytiga side effects included fluid retention, high blood pressure, and a drop in blood potassium levels.

FOR CHILDRENS: Sunlight worsens jet pollution

In the United States, nearly 50,000 planes fly every day. They open their doors, start their engines and wait. People board, fasten their seatbelts and wait. The planes close their doors, taxi to the runway and wait. All that waiting adds up to a lot of pollution produced by the powerful jet engines as they run at low power without moving, something engineers refer to as idling.

“If you’re number 46 in line awaiting takeoff, you could spend an hour idling,” Allen Robinson told Science News. Robinson is a mechanical engineer at Carnegie Mellon University in Pittsburgh. He recently worked with other scientists on an experiment that measured the particles coming from idling jets.

In the new study, Robinson and his colleagues captured and measured that pollution, then let it sit in the sun and measured it again. When the sunlight struck the tiny molecules produced by the engines, it caused a chemical reaction. That reaction altered the pollution, making it potentially more harmful than when it was first spit out. After several hours in the sun, the mass of pollution particles had multiplied by 35, on average.

Those numbers “sort of blew our minds,” Robinson told Science News. The new measurement suggests that scientists may be seriously underestimating the pollution produced at airports.

Previous studies have measured the polluting particles and gases coming directly from a jet engine. The new study is the first to measure the sun’s impacts on jet pollution. Getting an accurate measurement of a jet’s pollution is “very important to be clear on how aircraft emissions impact local and regional air quality,” Richard Miake-Lye told Science News. Miake-Lye, who did not participate in the new study, works at Aerodyne Research in Billerica, Mass.

To capture and measure the pollution, Robinson and his colleagues used a giant, inflatable bag called a smog chamber. The smog chamber could hold 7 cubic meters, which is about the same volume as two large cars. The team filled the bag with emissions from the jet, collected from about three feet behind the engine.

The sunlight or UV light started a process called photooxidation. Photo refers to light and oxidation refers to oxygen. So photooxidation happens when light and oxygen mix. In this case, the sunlight and oxygen caused solid particles of pollution to form out of the jet’s emission of gases and microscopic liquid fuel droplets. The scientists found that photooxidation boosted the number of pollution particles created when the engines are idling — and also when they’re using even more power, like during takeoff.

Even as cars and trucks produce less pollution, airports are going in the opposite, upward direction. Now coming from an airport near you: more pollution, and of a very bad variety. And it’s at its worst as you’re waiting, waiting, waiting for takeoff.

Brains of Breast-Feeding Moms More Responsive to Baby's Cries

In a finding that won't surprise many mothers, a new study says breast-feeding may help secure the bond between mother and child. But the study also offers one explanation how: through a change in the mother's brain.

The brains of breast-feeding mothers show a greater response to the sound of their babies' cries than do the brains of mothers who do not breast-feed, the study researchers say.

This boost in brain activity is seen in brain regions associated with mothering behaviors.

The results suggest this brain activity facilitates greater sensitivity from the mother toward her infant as the baby begins to socially interact with the world, the researchers say.

The study may help people to "recognize that it's important to support mothers who do want to breast-feed," said study researcher Pilyoung Kim, of the National Institute of Mental Health.

I understand the challenges mothers have," Kim said. "Regardless of their decision, I think it is critical during this early postpartum period that they seek support and encouragement from others, especially when they feel very stressed and challenged by the new demands because of the new parenting experience.

India is heart the of Accenture: CEO

BANGALORE: Consulting and technology giant Accenture houses around a third of its employees in India.

Speaking exclusively to TOI on a visit to Bangalore, Accenture CEO Pierre Nanterme described India as the heart of Accenture and said the company's employee base in India would be 70,000 by August this year, the highest in any one country.

The US has the second largest employee number at around 30,000. Accenture globally has 215,000 people.

The $22-billion Accenture's strength in India shows yet again how critical the country has become to the world's technology giants. IBM does not reveal country figures, but is said to be the second biggest IT employer in India, after TCS.

Capgemini has a third of its employee base in India, higher than France.
"The quality of engineers in India is spectacular . In the West, with an ageing population, there is a significant shortage of people with skills in maths, science and engineering," Nanterme said. He said India is now at the heart of Accenture's global operations in technology.

Fake anti-virus scam hits the Apple

It is one of the first major campaigns that cyber crooks have launched against Mac users. To date, criminals have focused on writing malicious software for machines running Microsoft Corp' Windows system, which inhabits more than nine of every 10 personal computers.

But as Macs have grown in number, they have become more attractive targets.

The fake anti-virus malware is downloaded when people click on links from tainted search engine results for popular queries, according to anti-virus software . It also spreads when users click on links to malicious sites that might be included in emails, Tweets or Facebook messages.

Apple said it will issue an update for its Mac operating system "in the coming days" that will automatically find and remove malicious fake anti-virus software. It will also warn Mac users when they download such programs.

In the meantime, Apple has issued advice on how users can clean up machines that have been infected by the malicious software, which goes by names including MacDefender, MacProtector and MacSecurity.