Jan 21, 2012

Controversial Killer Flu Research Paused

Researchers developing extra-contagious strains of H5N1 avian influenza have agreed to pause their work for 60 days.

The moratorium, announced Jan. 20 in Nature and Science, is a response to public fear and alarm in the scientific community, which has split over whether the research could inadvertently lead to release of a nightmare disease.

Depending on perspective, the moratorium is either a genuine recognition of the need for broader discussion or a public relations gesture. Either way, it’s a chance for everyone to catch their breath without reaching for a mask.

Fear that the viruses “may escape from the laboratories has generated intense public debate in the media on the benefits and potential harm of this type of research,” the researchers wrote in an open letter declaring the moratorium. “To provide time for these discussions, we have agreed on a voluntary pause of 60 days on any research involving highly pathogenic avian influenza H5N1 viruses leading to the generation of viruses that are more transmissible in mammals.”

The controversy began in November when ScienceInsider reported that two teams of virologists — one led by Ron Fouchier of Erasmus Medical Center in the Netherlands , the other by Yoshihiro Kawaoka at the University of Wisconsin — had developed H5N1 strains capable of passing easily between ferrets, which are used as models for influenza infection in humans. Whether the strains are as easily transmissible between people isn’t known, but is considered possible.

In humans, H5N1 is extraordinarily virulent — mortality runs between 60 and 80 percent — but far less contagious, requiring prolonged contact with infected birds or people. That it could become more contagious is a public health fear of the first order: Containing an outbreak would be extremely difficult, perhaps impossible, and millions of people would almost certainly die. It’s also a fear full of scientific unknowns. Despite a seemingly simple genome containing just a handful of genes, scientists don’t know what mutations could make H5N1 more transmissible between humans.

The research by Fouchier, Kawaoka and other labs was intended to identify those mutations, giving researchers an idea of what to look for in naturally evolving influenza, and perhaps allowing for early warning of strains that are just a few mutations away from causing human pandemics. But when the general outlines of the research became public — detailed descriptions await formal publication, and key details will be redacted at the request of a federal biosecurity committee — outrage followed.

Critics, including many high-profile virologists, epidemiologists and biosecurity experts, said it was possible that would-be biological terrorists could use the research to develop weaponized flu strains. Another, perhaps more frightening possibility was unintentional release: dozens of accidental infections (.pdf) have occurred at high-security laboratories in the United States, and it’s thought that one now-global flu strain may actually have escaped from a Russian laboratory in the 1970s. Against these risks, the benefits were arguable, and some virologists even said that mutations engineered in a laboratory didn’t necessarily illuminate future dangers.

“The research should never have been undertaken because the potential harm is so catastrophic and the potential benefits from studying the virus so speculative,” opined the New York Times in a Jan. 8 editorial entitled “An Engineered Doomsday.”

By declaring the 60 day moratorium, which will pause both further H5N1 engineering and experiments on the existing mutant strains, the researchers attempt to allay these fears.

“We recognize that we and the rest of the scientific community need to clearly explain the benefits of this important research and the measures taken to minimize its possible risks,” they write. “We propose to do so in an international forum in which the scientific community comes together to discuss and debate these issues.”

Reception to the moratorium appears mixed. Michael Osterholm, head of the University of Minnesota’s Center for Infectious Disease Research and Policy and a member of the federal committee that recommended redacting the findings, told Nature News that 60 days is far too short a time for developing any meaningful policies. “I just don’t think that’s realistic,” he said.

Richard Ebright, a Rutgers University microbiologist and vocal critic of the research, called the moratorium “an empty gesture. Strictly public relations.”

Contrary to the researchers’ insistence that the work was “using the highest international standards of biosafety and biosecurity,” it was conducted at so-called Biosafety Level 3 — a set of techniques and safeguards less strict than is used for Ebola and the Marburg virus, which pose less potential threat than an H5N1 strain that easily infects people. And outside of biosafety committees at researchers’ institutions, there appears to have been no official discussion of potential safety risks until the controversy made it unavoidable.

Read more at Wired Science

Carbon Dioxide Is 'Driving Fish Crazy'

Rising human carbon dioxide emissions may be affecting the brains and central nervous system of sea fishes with serious consequences for their survival, an international scientific team has found.

Carbon dioxide concentrations predicted to occur in the ocean by the end of this century will interfere with fishes' ability to hear, smell, turn and evade predators, says Professor Philip Munday of the ARC Centre of Excellence for Coral Reef Studies and James Cook University.

"For several years our team have been testing the performance of baby coral fishes in sea water containing higher levels of dissolved CO2 -- and it is now pretty clear that they sustain significant disruption to their central nervous system, which is likely to impair their chances of survival," Prof. Munday says.

In their latest paper, published in the journal Nature Climate Change, Prof. Munday and colleagues report world-first evidence that high CO2 levels in sea water disrupts a key brain receptor in fish, causing marked changes in their behaviour and sensory ability.

"We've found that elevated CO2 in the oceans can directly interfere with fish neurotransmitter functions, which poses a direct and previously unknown threat to sea life," Prof. Munday says.

Prof. Munday and his colleagues began by studying how baby clown and damsel fishes performed alongside their predators in CO2-enriched water. They found that, while the predators were somewhat affected, the baby fish suffered much higher rates of attrition.

"Our early work showed that the sense of smell of baby fish was harmed by higher CO2 in the water -- meaning they found it harder to locate a reef to settle on or detect the warning smell of a predator fish. But we suspected there was much more to it than the loss of ability to smell."

The team then examined whether fishes' sense of hearing -- used to locate and home in on reefs at night, and avoid them during the day -- was affected. "The answer is, yes it was. They were confused and no longer avoided reef sounds during the day. Being attracted to reefs during daylight would make them easy meat for predators."

Other work showed the fish also tended to lose their natural instinct to turn left or right -- an important factor in schooling behaviour which also makes them more vulnerable, as lone fish are easily eaten by predators.

"All this led us to suspect it wasn't simply damage to their individual senses that was going on -- but rather, that higher levels of carbon dioxide were affecting their whole central nervous system."

The team's latest research shows that high CO2 directly stimulates a receptor in the fish brain called GABA-A, leading to a reversal in its normal function and over-excitement of certain nerve signals.

While most animals with brains have GABA-A receptors, the team considers the effects of elevated CO2 are likely to be most felt by those living in water, as they have lower blood CO2 levels normally. The main impact is likely to be felt by some crustaceans and by most fishes, especially those which use a lot of oxygen.

Prof. Munday said that around 2.3 billion tonnes of human CO2 emissions dissolve into the world's oceans every year, causing changes in the chemical environment of the water in which fish and other species live.

"We've now established it isn't simply the acidification of the oceans that is causing disruption -- as is the case with shellfish and plankton with chalky skeletons -- but the actual dissolved CO2 itself is damaging the fishes' nervous systems."

Read more at Science Daily

Jan 20, 2012

When It Comes to Accepting Evolution, Gut Feelings Trump Facts

For students to accept the theory of evolution, an intuitive "gut feeling" may be just as important as understanding the facts, according to a new study.

In an analysis of the beliefs of biology teachers, researchers found that a quick intuitive notion of how right an idea feels was a powerful driver of whether or not students accepted evolution -- often trumping factors such as knowledge level or religion.

"The whole idea behind acceptance of evolution has been the assumption that if people understood it -- if they really knew it -- they would see the logic and accept it," said David Haury, co-author of the new study and associate professor of education at Ohio State University.

"But among all the scientific studies on the matter, the most consistent finding was inconsistency. One study would find a strong relationship between knowledge level and acceptance, and others would find no relationship. Some would find a strong relationship between religious identity and acceptance, and others would find less of a relationship."

"So our notion was, there is clearly some factor that we're not looking at," he continued. "We're assuming that people accept something or don't accept it on a completely rational basis. Or, they're part of a belief community that as a group accept or don't accept. But the findings just made those simple answers untenable."

Haury and his colleagues tapped into cognitive science research showing that our brains don't just process ideas logically -- we also rely on how true something feels when judging an idea. "Research in neuroscience has shown that when there's a conflict between facts and feeling in the brain, feeling wins," he says.

The researchers framed a study to determine whether intuitive reasoning could help explain why some people are more accepting of evolution than others. The study, published in the Journal of Research in Science Teaching, included 124 pre-service biology teachers at different stages in a standard teacher preparation program at two Korean universities.

First, the students answered a standard set of questions designed to measure their overall acceptance of evolution. These questions probed whether students generally believed in the main concepts and scientific findings that underpin the theory.

Then the students took a test on the specific details of evolutionary science. To show their level of factual knowledge, students answered multiple-choice and free-response questions about processes such as natural selection. To gauge their "gut" feelings about these ideas, students wrote down how certain they felt that their factually correct answers were actually true.

The researchers then analyzed statistical correlations to see whether knowledge level or feeling of certainty best predicted students' overall acceptance of evolution. They also considered factors such as academic year and religion as potential predictors.

"What we found is that intuitive cognition has a significant impact on what people end up accepting, no matter how much they know," said Haury. The results show that even students with greater knowledge of evolutionary facts weren't likelier to accept the theory, unless they also had a strong "gut" feeling about those facts.

When trying to explain the patterns of whether people believe in evolution or not, "the results show that if we consider both feeling and knowledge level, we can explain much more than with knowledge level alone," said Minsu Ha, lead author on the paper and a Ph.D. candidate in the School of Teaching and Learning.

In particular, the research shows that it may not be accurate to portray religion and science education as competing factors in determining beliefs about evolution. For the subjects of this study, belonging to a religion had almost no additional impact on beliefs about evolution, beyond subjects' feelings of certainty.

These results also provide a useful way of looking at the perceived conflict between religion and science when it comes to teaching evolution, according to Haury. "Intuitive cognition not only opens a new door to approach the issue," he said, "it also gives us a way of addressing that issue without directly questioning religious views."

When choosing a setting for their study, the team found that Korean teacher preparation programs were ideal. "In Korea, people all take the same classes over the same time period and are all about the same age, so it takes out a lot of extraneous factors," said Haury. "We wouldn't be able to find a sample group like this in the United States."

Unlike in the U.S., about half of Koreans do not identify themselves as belonging to any particular religion. But according to Ha, who is from Korea, certain religious groups consider the topic of evolution just as controversial as in the U.S.

To ensure that their results were relevant to U.S. settings, the researchers compared how the Korean students did on the knowledge tests with previous studies of U.S. students. "We found that the both groups were comparable in terms of the overall performance," said Haury.

For teaching evolution, the researchers suggest using exercises that allow students to become aware of their brains' dual processing. Knowing that sometimes what their "gut" says is in conflict with what their "head" knows may help students judge ideas on their merits.

"Educationally, we think that's a place to start," said Haury. "It's a concrete way to show them, look -- you can be fooled and make a bad decision, because you just can't deny your gut."

Read more at Science Daily

Scientists Solve Mystery of Colorful Armchair Nanotubes

Rice University researchers have figured out what gives armchair nanotubes their unique bright colors: hydrogen-like objects called excitons.

Their findings appear in the online edition of the Journal of the American Chemical Society.

Armchair carbon nanotubes -- so named for the "U"-shaped configuration of the atoms at their uncapped tips -- are one-dimensional metals and have no band gap. This means electrons flow from one end to the other with little resistivity, the very property that may someday make armchair quantum wires possible.

The Rice researchers show armchair nanotubes absorb light like semiconductors. An electron is promoted from an immobile state to a conducting state by absorbing photons and leaving behind a positively charged "hole," said Rice physicist Junichiro Kono. The new electron-hole pair forms an exciton, which has a neutral charge.

"The excitons are created by the absorption of a particular wavelength of light," said graduate student and lead author Erik Hároz. "What your eye sees is the light that's left over; the nanotubes take a portion of the visible spectrum out." The diameter of the nanotube determines which parts of the visible spectrum are absorbed; this absorption accounts for the rainbow of colors seen among different batches of nanotubes.

Scientists have realized that gold and silver nanoparticles could be manipulated to reflect brilliant hues -- a property that let artisans who had no notions of "nano" create stained glass windows for medieval cathedrals. Depending on their size, the particles absorbed and emitted light of particular colors due to a phenomenon known as plasma resonance.

In more recent times, researchers noticed semiconducting nanoparticles, also known as quantum dots, show colors determined by their size-dependent band gaps.

But plasma resonance happens at wavelengths outside the visible spectrum in metallic carbon nanotubes. And armchair nanotubes don't have band gaps.

Kono's lab ultimately determined that excitons are the source of color in batches of pure armchair nanotubes suspended in solution.

The results seem counterintuitive, Kono said, because excitons are characteristic of semiconductors, not metals. Kono is a professor of electrical and computer engineering and of physics and astronomy.

While armchair nanotubes don't have band gaps, they do have a unique electronic structure that favors particular wavelengths for light absorption, he said.

"In armchair nanotubes, the conduction and valence bands touch each other," Kono said. "The one-dimensionality, combined with its unique energy dispersion, makes it a metal. But the bands develop what's called a van Hove singularity," which appears as a peak in the density of states in a one-dimensional solid. "So there are lots of electronic states concentrated around this singularity."

Exciton resonance tends to occur around these singularities when hit with light, and the stronger the resonance, the more distinguished the color. "It's an unusual quality of these particular one-dimensional materials that these excitons can actually exist," Hároz said. "In most metals, that's not possible; there's not enough Coulomb interaction between the electron and the hole for an exciton to be stable."

The new paper follows on the heels of work by Kono and his team to create batches of pure single-walled carbon nanotubes through ultracentrifugation. In that process, nanotubes were spun in a mix of solutions with different densities up to 250,000 times the force of gravity. The tubes naturally gravitated toward separated solutions that matched their own densities to create a colorful "nano parfait."

As a byproduct of their current work, the researchers proved their ability to produce purified armchair nanotubes from a variety of synthesis techniques. They now hope to extend their investigation of the optical properties of armchairs beyond visible light. "Ultimately, we'd like to make one collective spectrum that includes frequency ranges all the way from ultraviolet to terahertz," Hároz said. "From that, we can know, optically, almost everything about these nanotubes."

Co-authors of the paper include Robert Hauge, a distinguished faculty fellow in chemistry at Rice; Rice alumnus Benjamin Lu; and professors Pavel Nikolaev and Sivaram Arepalli of Sungkyunkwan University, Suwon, Korea.

Read more at Science Daily

Almost Perfect: Researcher Nears Creation of Superlens

A superlens would let you see a virus in a drop of blood and open the door to better and cheaper electronics. It might, says Durdu Guney, make ultra-high-resolution microscopes as commonplace as cameras in our cell phones.

No one has yet made a superlens, also known as a perfect lens, though people are trying. Optical lenses are limited by the nature of light, the so-called diffraction limit, so even the best won't usually let us see objects smaller than 200 nanometers across, about the size of the smallest bacterium. Scanning electron microscopes can capture objects that are much smaller, about a nanometer wide, but they are expensive, heavy, and, at the size of a large desk, not very portable.

To build a superlens, you need metamaterials: artificial materials with properties not seen in nature. Scientists are beginning to fabricate metamaterials in their quest to make real seemingly magical phenomena like invisibility cloaks, quantum levitation -- and superlenses.

Now Guney, an assistant professor of electrical and computer engineering at Michigan Technological University, has taken a major step toward creating superlens that could use visible light to see objects as small as 100 nanometers across.

The secret lies in plasmons, charge oscillations near the surface of thin metal films that combine with special nanostructures. When excited by an electromagnetic field, they gather light waves from an object and refract it in a way not seen in nature called negative refraction. This lets the lens overcomes the diffraction limit. And, in the case of Guney's model, it could allow us to see objects smaller than 1/1,000th the width of a human hair.

Other researchers have also been able to sidestep the diffraction limit, but not throughout the entire spectrum of visible light. Guney's model showed how metamaterials might be "stretched" to refract light waves from the infrared all the way past visible light and into the ultraviolet spectrum.

Making these superlenses would be relatively inexpensive, which is why they might find their way into cell phones. But there would be other uses as well, says Guney.

"It could also be applied to lithography," the microfabrication process used in electronics manufacturing. "The lens determines the feature size you can make, and by replacing an old lens with this superlens, you could make smaller features at a lower cost. You could make devices as small as you like."

Computer chips are made using UV lasers, which are expensive and difficult to build. "With this superlens, you could use a red laser, like the pointers everyone uses, and have simple, cheap machines, just by changing the lens."

What excites Guney the most, however, is that a cheap, accessible superlens could open our collective eyes to worlds previously known only to a very few.

"The public's access to high-powered microscopes is negligible," he says. "With superlenses, everybody could be a scientist. People could put their cells on Facebook. It might just inspire society's scientific soul."

Read more at Science Daily

Monkey Feared Extinct Rediscovered

An elusive monkey feared extinct has shown up in the remote forests of Borneo, posing for the first good pictures of the animal ever taken.

The mug shots reveal a furry Count Dracula of sorts, with the monkey's black head, face tipped with white whiskers and a pointy collar made of fluffy white fur.

The Miller's grizzled langur, an extremely rare primate that has suffered from habitat loss over the last 30 years, popped up unexpectedly in the protected Wehea Forest in east Kalimantan, Borneo.

"We knew we had found this primate that some people had speculated was potentially extinct," said study researcher Stephanie Spehar, a primatologist at the University of Wisconsin Oshkosh. "It was really exciting."

But the animal is still in grave danger, Spehar told LiveScience, and no one knows how many of these langurs are left. The researchers observed only two small groups of them.

Vanishing act

The shy monkey (Presbytis hosei canicrus) was seen in the 1970s in Kutai National Park in Borneo, about 50 miles (80 kilometers) from where the new population lives. But as the years passed, fires and illegal logging devastated Kutai. By 2008, the Miller's grizzled langur seems to have vanished from the park. A survey that year found just five langurs living on the Sangkulirang Peninsula in East Kalitmantan, also about 50 miles (80 km) away from the newly discovered langur habitat. But by 2010, that group of primates had also disappeared.

"At this point, we didn't know if this animal still existed or whether it was still hiding out in little pockets," Spehar said.

Spehar has been working in the Wehea Forest of Borneo for four years, but she'd never seen a Miller's grizzled langur there. Last summer, however, one of her undergraduate students camped out by a mineral lick area for 10 days, a spot where animals come to get nutrients from mineral-rich soil and water. The student, Eric Fell, was conducting his own research project on animals' use of these licks, and was photographing the creatures that dropped by.

Upon returning from his stakeout, Fell showed Spehar his photographs. Among them were images of long-tailed, black-headed langurs.

"I knew this was something special," Spehar said. "I knew that it was something that was unexpected and we hadn't seen before."

Spehar, who credits the find to the work of local communities and governments that protect the forest and support her research, showed the photos to another researcher working in the woods, the director of the conservation organization Ethical Expeditions Brent Loken. The revelation surprised both parties: It turned out that Loken's group had also been staking out a mineral lick 5 miles (8 km) away from Fell's with a motion-triggered camera. They'd captured an image of the same type of primate.



"We realized that we had basically rediscovered this animal," Spehar said. Taxonomists confirmed the find as a Miller's grizzled langur. The researchers reported their find today in the American Journal of Primatology.

The simultaneous discovery suggests that there is a decent-size population of the langurs in Wehea, but Spehar cautioned that incredibly little is known about the species. No one knows how wide the langurs' range is, she said, how many there are, or their population density. That lack of knowledge isn't uncommon for many threatened species, according to Loken.

"This monkey represents a lot of species on the planet that we know very little about," Loken told LiveScience. "We don't know how many there are, we don't know where they live, what ecological requirements they need to live, and unless we get some of that information quickly, some of these species could slip into extinction before we know anything about them, or even realize that they're gone."

While Wehea itself is a more than 98,000-acre (40,000-hectare) oasis of protection, it is surrounded by forest used for logging, palm oil plantations and mining — the same sort of human uses that presumably drove the langurs out of the habitats where they once thrived. Additionally, the forest is only protected by the local community, Loken said, not the central government.

Read more at Discovery News

Jan 19, 2012

How a Diamond Is Like a Champagne Cork

Scientists have long known that a diamond’s trip from deep below Earth’s surface must be quick indeed: Lab tests show that at conditions found in the crust, the gems would burn up in a matter of days, if not hours. New experiments reveal the chemical secret behind such rapid ascent. The eruptions of diamonds to Earth’s surface may be driven by massive quantities of carbon dioxide fizzing from the molten rock that surrounds the gems.

Many diamonds are embedded in a dense volcanic rock called kimberlite, which gets its name from the town of Kimberley, South Africa, where several of the world’s first diamond mines were discovered. It’s difficult to explain how relatively heavy, crystal-rich magma becomes buoyant enough to rapidly rise through Earth’s crust, so researchers have long suspected that volatile substances dissolved in the rock, such as water and carbon dioxide, play a major role in kimberlite eruptions, says Kelly Russell, a volcanologist at the University of British Columbia in Vancouver, Canada. Nevertheless, scientists have been baffled about how and why these substances begin to froth out of material in the mantle. Pressures there are typically so high that they would keep gases locked in the molten rock, just as pressure keeps carbon dioxide dissolved in a carbonated drink.

New lab tests by Russell and his colleagues provide hints about how the fizz gets started. The experiments show that in molten rock that’s rich in carbonates, carbon dioxide is exceptionally soluble. But the researchers found that in molten rock that’s rich in silica, carbon dioxide is only between one-fourth and one-third as soluble, regardless of the pressure. In the team’s early tests, the researchers used a salt shaker to sprinkle a silica-rich mineral called orthopyroxene onto a puddle of molten, carbonate-rich rock. As the mineral dissolved into the puddle over the course of 20 minutes or so, the carbon dioxide vigorously bubbled out: “It foamed right in front of our eyes,” Russell says. “It blew me away.”

The lab tests mimic what goes on in the earliest phase of a kimberlite eruption deep inside Earth, the researchers speculate. First, a pocket of carbonate-rich molten rock comes into contact with silica-rich minerals somewhere in the upper mantle, where rocks contain between 15% and 27% orthopyroxene. Carbon dioxide fizzes out of the molten material, rendering the dense magma buoyant. As the magma surges upward from the upper mantle at speeds up to 14 kilometers per hour, it pummels its way into overlying rocks that contain even more silica, which accelerates the fizzing even further. At such rates, the frothy kimberlite lava could reach Earth’s surface from a depth of up to 120 kilometers in between 3 and 8 hours, Russell estimates.

The chemical reaction that drives the fizzing is largely self-sustaining, Russell says. The heat needed to keep the reaction going comes from the crystallization of other minerals such as olivine, he notes.

“This is an excellent paper that really helps fill in some important parts of the kimberlite puzzle,” says James Head III, a planetary geologist at Brown University. For instance, because kimberlites are readily eroded and easily altered by long-term exposure to the elements at or near Earth’s surface, clues about the original chemical composition of kimberlites in their molten state are rare.

Read more at Wired Science

Sumerian Beer a Non-alcoholic Brew?

Brewers like to trace the history of their art back to ancient Sumer in Mesopotamia, but cuneiform writing scholar Peter Damerow of the Max Planck Institute might have burst the bubble on their beer foam.

“Given our limited knowledge about the Sumerian brewing processes, we cannot say for sure whether their end product even contained alcohol”, wrote Damerow in the Cuneiform Digital Library Journal.

Many 4,000 year old cuneiform tablets refer to deliveries of wheat, barley, and malt to Sumerian breweries, and the Hymn of Ninkasi from about 1800 BC praises brewing. But there are no hard details about the process.

Beer historians believed that the Sumerians first prepared bread, then used that to make “bappir,” Sumerian for bread beer. But Damerow notes that cuneiform tablets never make this clear and only record measurements of the raw ingredients.

Archaeologists from the Ludwig Maximilian Universität together with brewing experts from the Technische Universität München carried out an experiment near the archeological site of Tall Bazi, Syria in an attempt to replicate the bygone beer of Sumer.

Damerow believed that although the experiment produced a brew, it only demonstrated that modern methods can produce a beer under the conditions at Tall Bazi. But he did think the Tall Bazi experiment was a step in the right direction towards understanding how the Sumerians got their drink on.

Read more at Discovery News

Why Does Our Universe Have Three Dimensions?

Why does our universe look the way it does? In particular, why do we only experience three spatial dimensions in our universe, when superstring theory, for instance, claims that there are ten dimensions -- nine spatial dimensions and a tenth dimension of time?

Japanese scientists think they may have an explanation for how a three-dimensional universe emerged from the original nine dimensions of space. They describe their new supercomputer calculations simulating the birth of our universe in a forthcoming paper in Physical Review Letters.

Before we delve into the mind-bending specifics, it's helpful to have a bit of background.

The Big Bang theory of how the universe was born has been bolsted by some pretty compelling observational evidence, including the measurement of the cosmic microwave background and the relative abundance of elements.

But while cosmologists can gaze back in time to within a few seconds of the Big Bang, at the actual moment it came into existence, when the whole universe was just a tiny point -- well, at that point, the physics we know and love breaks down. We need a new kind of theory, one that combines relativity with quantum mechanics, to make sense of that moment.

Over the course of the 20th century, physicists painstakingly cobbled together a reasonably efficient "standard model" of physics. The model they came up with almost works, without resorting to extra dimensions. It merges electromagnetism with the strong and weak nuclear forces (at almost impossibly high temperatures), despite the differences in their respective strengths, and provides a neat theoretical framework for the big, noisy "family" of subatomic particles.

But there is a gaping hole. The standard model doesn't include the gravitational force. That's why Jove, the physicist in Jeanette Winterson's novel, Gut Symmetries, calls the Standard Model the "Flying Tarpaulin" -- it's "big, ugly, useful, covers what you want and ignores gravity.” Superstring theory aims to plug that hole.

Pulling Strings

According to string theorists, there are the three full-sized spatial dimensions we experience every day, one dimension of time, and six extra dimensions crumpled up at the Planck scale like itty-bitty wads of paper. As tiny as these dimensions are, strings -- the most fundamental unit in nature, vibrating down at the Planck scale -- are even smaller.

The geometric shape of those extra dimensions helps determine the resonant patterns of string vibration. Those vibrating patterns in turn determine the kind of elementary particles that are formed, and generate the physical forces we observe around us, in much the same way that vibrating fields of electricity and magnetism give rise to the entire spectrum of light, or vibrating strings can produce different musical notes on a violin.

All matter (and all forces) are composed of these vibrations -- including gravity. And one of the ways in which strings can vibrate corresponds to a particle that mediates gravity.

Voila! General relativity has now been quantized. And that means string theory could be used to explore the infinitely tiny point of our universe's birth (or, for that matter, the singularity that lies at the center of a black hole).

Shattered Symmetry

There's one more wrinkle, and that's this whole business of extra dimensions, when our world as we currently experience it has only three. Physicists have hammered out a pretty convincing hypothetical scenario for how this might have come about.

Before the Big Bang, the cosmos was a perfectly symmetrical nine-dimensional universe (or ten, if you add in the dimension of time) with all four fundamental forces unified at unimaginably high temperatures. But this universe was highly unstable and cracked in two, sending an immense shock wave reverberating through the embryonic cosmos.

The result was two separate space-times: the unfurled three-dimensional one that we inhabit, and a six-dimensional one that contracted as violently as ours expanded, shrinking into a tiny Planckian ball. As our universe expanded and cooled, the four forces split off one by one, beginning with gravity. Everything we see around us today is a mere shard of the original shattered nine-dimensional universe.

Physicists who espouse this view aren't sure why it happened, but they suspect it might be due to the incredible tension and high energy required to maintain a supersymmetric state, which could render it inherently unstable.

Imagine that you are trying to making the bed on laundry day, but the bed sheet has shrunk slightly in the wash. You manage to get it to fit around all four corners of the bed, but the sheet is stretched so tightly that it just won't stay in place.

There is too much strain on the fabric, so one corner inevitably pops loose, causing the bed sheet to curl up in that spot. Sure, you can force that corner back into place, but again, the strain will prove to be too much and another corner will pop.

Like the bed sheet, the original ten-dimensional fabric of space-time was stretched tight in a supersymmetric state. But the tension became too great, and space-time cracked in two. One part curled up into a tight little ball, while the aftershock from the cataclysmic cosmic cracking caused the other part to expand outward rapidly, a period known as inflation. This became our visible universe.

Read more at Discovery News

NASA Debunks Mysterious Triangular 'UFO'

Once again, alien conspiracy theorists have attempted to use publicly available NASA images to prove that the space agency must be engaging in an elaborate UFO cover-up. And, once again, they've been foiled by the laws of physics.

This time, they called attention to peculiar new footage captured by a telescope onboard NASA's STEREO-B spacecraft — one of a pair of probes parked on either side of the sun which, together, provide a 360-degree view of the inner solar system. The footage shows Venus, Earth and, on the opposite side of the field-of-view, a mysterious triangular object headed our way.

"Comparing it for size to the planetary objects that are seen in this telescope, if my calculations are correct, that thing is enormous," said YouTube user 'BeePeeOilDisaster' in his video commentary on the footage, which was captured Dec. 27 -29. Talk of a cover-up quickly followed when, a few days later, NASA scientists updated the STEREO website to display newer images.

This is not the first time alien hunters have found what they believe to be enormous UFOs in images captured by the STEREO probes. (Mysterious Planet-Size Object Spotted Near Mercury)

But this time, the team of scientists who work with data from the probes decided to address the claim directly. In a post on the STEREO website, the researchers offered up an explanation of the triangular feature in the December footage. The researchers say its no more than a trick of the light.

"The answer lies on the exact opposite side of the image," the scientists wrote. "At the same time as this strange-looking feature starts being visible, the very bright planet Venus enters the [telescopic camera's] field-of-view from the lower left."

The scientists note that Venus and the triangle, opposite each other across the middle of the camera plane, stay in step as they move. "This is not a coincidence. The strange-looking geometrical 'object' is actually an internal reflection of the planet Venus within the telescope optics. This effect has been seen many times before."

Read more at Discovery News

Jan 18, 2012

Prehistoric Predators With Supersized Teeth Had Beefier Arm Bones

The toothiest prehistoric predators also had beefier arm bones, according to results of a study published recently in the journal Paleobiology.

Saber-toothed tigers may come to mind, but these extinct cats weren't the only animals with fearsome fangs.

Take the false saber-toothed cats -- also known as nimravids -- and their catlike cousins, a family of carnivores called the barbourofelids.

These mammal groups lived millions of years before cats came to be, and had knife-like canines along with well-built arm bones, said Julie Meachen, a paleontologist at the National Science Foundation (NSF) National Evolutionary Synthesis Center (NESCent) in Durham, North Carolina.

This killer combination arose repeatedly in different saber-toothed predators over time, presumably because it gave them an advantage when catching and killing prey, Meachen found.

"This is a nice demonstration that selection usually operates on suites of traits to generate solutions to environmental challenges," said Saran Twombly, program director in NSF's Directorate for Biological Sciences, which funds NESCent.

"In this case, the key to being an efficient predator integrated canines and forelimbs across different groups of felids and led to the development of different combinations of these traits," said Twombly. "It was the combination, rather than any single trait, that allowed a diverse group of organisms to thrive as predators."

The long, thin teeth of saber-toothed cats look formidable, but they're fragile compared with those of felines today.

"Cats now have canines that are short and round in cross-section, so they can withstand forces in all directions," Meachen said.

"That comes in handy for hunting -- their teeth are better able to withstand the stress and strain of struggling prey without breaking."

In contrast, the elongated canines of saber-toothed cats were flattened side-to-side and were more oval, which made them more vulnerable to fracture.

In previous results published in 2010, Meachen reported that the saber-toothed cat Smilodon fatalis had exceptionally thick arm bones when compared with its feline cousins.

"Thick, robust bones are an indicator of forelimb strength," Meachen said.

The results suggest that these animals may have relied on their forelimbs to help catch and kill their prey without fracturing their fangs.

In studying the fossil skeletons of other saber-toothed predators, Meachen had a hunch that the combination of fragile knife-like canines and beefy arm bones might not have been unique to saber-toothed cats.

Earth was once home to a number of toothy carnivores that no longer roam the wilds.

Nimravids were meat-eaters that flourished for almost 35 million years, from about 42 to 7 million years ago, alongside another group of extinct predators, the barbourofelids, which lived from 17 to 9 million years ago, when they died out.

"If you saw one of these animals you'd probably think it was a cat, but true cats didn't evolve until millions of years later," Meachen said.

The animals left no living descendants, but thanks to fossilized bones scientists know that their upper canines came in a wide range of shapes and sizes.

Some species had canines that were short and round; others were long, flattened and more oval. Some were serrated "like a steak knife," Meachen said.

To find out if saber-toothed predators with longer, thinner teeth and delicate dentition generally had thicker forelimbs, Meachen measured the fossilized arm bones and upper canines of hundreds of museum specimens of extinct cats, nimravids and barbourofelids that once roamed North America.

She also measured the teeth and arm bones of 13 cat species living today -- such as the tiger and the clouded leopard -- all of which have conical teeth.

When she compared the dimensions of the teeth to those of the arms, she found that each group of animals gradually converged on the same solution--the longer the teeth, the thicker the forelimbs.

The results held up even after taking into account that larger species generally have bigger bones.

She attributes the striking similarities among the species to convergent evolution.

"The same correlated sets of traits arose repeatedly through time," Meachen said.

Read more at Science Daily

A SOPA/PIPA Blackout Explainer

Hundreds, if not thousands, of websites are expected to go dark or alter themselves Wednesday to protest proposed U.S. anti-piracy legislation that many believe goes too far fighting online copyright and trademark infringement.

Josh Levy, campaign manager for Free Press, said in a Tuesday conference call supporting the protest that “This is the biggest revolt we’ve seen online” against U.S. legislation.

The websites are expected to participate in the protest against the Senate’s Protect IP Act and the House’s Stop Online Piracy Act. They include brand names like Wikipedia, Wired, BoingBoing and the Electronic Frontier Foundation to little-known sites likes political action committee DemocracyForAmerica.

But what’s all the fuss about? Here’s an explainer of the basics of the bills, the protests and how you make your voice heard.

What prompted the protest?

*The expected protest comes despite the White House announcing Saturday it would not support the bills if they mandate changes to internet infrastructure, which was the most egregious provision in the measures that prompted the protests.

Leaders in the House and Senate also buckled to widespread pressure and announced they would at least temporarily remove those DNS-redirecting requirements. That provision would have required ISPs to prevent Americans from visiting blacklisted sites by altering the system known as DNS that turns site names like Google.com into IP addresses such as 174.35.23.56. Instead, for the blacklisted sites, ISPs would have to lie to their customers and tell their browsers that the site doesn’t exist.

Unfortunately, that has serious security implications and undermines government-led efforts to prevent hackers from hijacking the net’s naming system in order to scam users. Those sites would disappear in a process that security experts said would damage internet security.

The SOPA and PIPA measures are now being reworked behind closed doors and are expected to exclude the DNS language.

If DNS blacklisting is off the table, why the protest?

While DNS blacklisting was the most egregious portion of the bill and a clear indicator that Congress didn’t know what it was doing, what’s left in the bills continue to have serious implications on the First Amendment and online freedom.

The bills give the Justice Department the power to seek court orders requiring search engines like Google not to render search results for infringing websites. (The proposals are vague and broad when it comes to defining an infringing site.)

The bills also allow the Justice Department to order internet service providers like Comcast and AT&T to block their users from visiting blacklisted sites. That would be unprecedented in the United States, though it’s a common tactic used in countries like Syria, Iran and China to clamp down on political dissent and adult content.

The SOPA proposal bars the distribution of tools and services designed to get around such blacklists. The ban could arguably cover tools such as VPNs and Tor used by human rights groups, government officials and businesses to protect their communications and evade online spying and filtering.

The proposals grant rights holders the ability to demand that judges order ad networks and financial institutions to refrain from doing business with sites right holders say are infringing.

The measures also give out legal immunity to ad networks and financial institutions that choose, without a court order, to stop placing ads or processing transactions for websites they deem are dedicated to infringing activity.

Copyright holders would face little penalty for filing takedown claims without doing due diligence or considering “fair use,” encouraging even more abuse of copyright takedown lawsuits.

Why are these bills on the table?

They are in response to Big Content’s (.pdf) arguments that hundreds of thousands of jobs are lost every year due to pirate websites. These numbers are largely unsubstantiated and rest on the assumption that if a person had not gotten a copy of a movie online, they would have paid full price for a DVD or CD.

On the other side, much of the tech world maintains that the open nature of the internet has created millions of jobs, that millions of people pay for content online and that copyright and trademark holders already have the legal tools to fight infringement.

Does the government or Big Content have a history of abusing the takedown process?

Unfortunately, copyright holders don’t always play fair. Universal Music already believes it does not have to consider fair use when sending YouTube a takedown notice under the Digital Millennium Copyright Act. The U.S. government has seized  and shut down a website for a year before giving it back to a New York music blogger falsely accused of facilitating copyright infringement.

What sites are targeted?
The legislation for the most part is directed at foreign websites dedicated to infringing activities. Think the Pirate Bay, for one, which supports itself with advertising. Sites ending in .com, .org or .net generally are not targeted, but the government says it already has the power to seize and shut down sites on those top-level domains in a program known as “Operation in Our Sites.”

However, the orders to block infringing sites will go to U.S.-based search engines, ad networks, payment processors and ISPs.

What’s the status of the bills?

The House bill is expected to return next month to the Judiciary Committee for a vote or possibly more testimony. The Senate bill could either go back to committee or it could just be replaced and voted on by the full Senate. No announcement has been made.

Read more at Wired

Snakes Methodically Kill Prey

Snakes do not just kill on instinct, but they instead monitor the condition of their victims right until the very end.

The tightness and duration of a constricting snake’s death squeeze are timed to perfection, matching the heartbeat and weakening state of the snake’s unfortunate prey, according to a study published in the latest Royal Society Biology Letters.

The findings reveal that snakes are far more intelligent than previously thought, capable of complex functions typically reserved for “higher” vertebrates. They are also master hunters, ready to kill at any given moment.

“A snake first detects its prey with visual and chemosensory means,” lead author Scott Boback, an assistant professor of biology at Dickinson College, told Discovery News. “In addition to these, Boas also have heat sensitive neurons located beneath their lip scales. These neurons can sense temperature differences in their environment, such as an endothermic prey animal.”

“They can kill their prey through a variety of means, including constriction, envenomation or a combination of both,” Boback added.

For the study, Boback and his colleagues caught 16 wild Boas, raising them in a temperature-controlled lab on a diet of dead chicks and rats. Some rat cadavers were outfitted with a simulated heart that permitted the researchers to control how it pumped.

The scientists next dangled the warmed, outfitted rats tantalizingly over the snakes. As the snakes went into their death grip, Boback and his team analyzed the pressure generated by the snakes. The snakes responded to the beating heart, constricting longer and with greater total pressure until the heartbeat ceased.


This video shows a boa striking and constricting during a kill.

Snakes naïve to live prey also responded to the simulated heart, suggesting that the behavior is partly innate. But experienced snake hunters perfectly timed their kills to the heartbeats.

“That suggests to us that snakes can learn how to change their constriction duration and pressure to effectively kill their prey,” Boback said.

He also explained that since snakes use a variety of cues to monitor the state of their victims, they would not waste their time squeezing an animal that does not die after a certain period of time.

During the study, if the researchers kept the simulated heartbeat in the rat cadaver going, the snake did eventually release the rodent.

Read more at Discovery News

Astronomers Aim To Take First Picture of Black Hole

Taking a picture of a black hole, an object so gravitationally bound that not even photons of light can escape, sounds like an oxymoron, but astronomers this week will attempt to do just that.

What they're hoping to glimpse is something called the "event horizon" -- the swirl of matter and energy that are visible around the rim of the black hole just before it falls into the abyss.

"Even five years ago, such a proposal would not have seemed credible," Sheperd Doeleman, assistant director of the Haystack Observatory at the Massachusetts Institute of Technology and the lead researcher on the project, called the Event Horizon Telescope, said in a press release.

"Now we have the technological means to take a stab at it," he added.

The target for the shoot is the supermassive black hole that lives in the heart of our galaxy, the Milky Way. It's about 4 million times as massive as the sun, but it's extremely compressed and far away, nearly 26,000 light-years. To astronomers, it's like looking at a grapefruit on the moon.

To see something that small and that far away, you need a very big telescope -- something Earth-sized ought to do it.

To that end, astronomers will attempt to link up to 50 radio telescopes scattered around the globe, including the Submillimeter Telescope on Mt. Graham in Arizona, telescopes on Mauna Kea in Hawaii and the Combined Array for Research in Millimeter-wave Astronomy in California. The global array will include several radio telescopes in Europe, a 10-meter dish at the South Pole and potentially a 15-meter antenna atop a 15,000-foot peak in Mexico.

"In essence, we are making a virtual telescope with a mirror that is as big as the Earth," Doeleman said.

Black holes were first suggested by Albert Einstein's General Theory of Relativity. Decades of research and observations have provided evidence of their existence, but it has never been possible to directly observe and image one.

"We will be able to actually see what happens very close to the horizon of a black hole, which is the strongest gravitational field you can find in the universe," said Dimitrios Psaltis, an associate professor of astrophysics at the Steward Observatory.

Read more at Discovery News

Jan 17, 2012

Hubble Zooms in On Double Nucleus in Andromeda Galaxy

A new Hubble Space Telescope image centers on the 100-million-solar-mass black hole at the hub of the neighboring spiral galaxy M31, or the Andromeda galaxy, the only galaxy outside the Milky Way visible to the naked eye and the only other giant galaxy in the local group.

This is the sharpest visible-light image ever made of the nucleus of an external galaxy.

The event horizon, the closest region around the black hole where light can still escape, is too small to be seen, but it lies near the middle of a compact cluster of blue stars at the center of the image. The compact cluster of blue stars is surrounded by the larger "double nucleus" of M31, discovered with the Hubble Space Telescope in 1992. The double nucleus is actually an elliptical ring of old reddish stars in orbit around the black hole but more distant than the blue stars. When the stars are at the farthest point in their orbit they move slower, like cars on a crowded freeway. This gives the illusion of a second nucleus.

The blue stars surrounding the black hole are no more than 200 million years old, and therefore must have formed near the black hole in an abrupt burst of star formation. Massive blue stars are so short-lived that they would not have enough time to migrate to the black hole if they were formed elsewhere.

Astronomers are trying to understand how apparently young stars were formed so deep inside the black hole's gravitational grip and how they survive in an extreme environment.

The fact that young stars are also closely bound to the central black hole in our Milky Way galaxy suggests this may be a common phenomenon in spiral galaxies.

Tod R. Lauer of the National Optical Astronomy Observatory in Tucson, Ariz., assembled this image of the nuclear region by taking several blue and ultraviolet light exposures of the nucleus with Hubble's Advanced Camera for Surveys high-resolution channel, each time slightly moving the telescope to change how the camera sampled the region. By combining these pictures, he was able to construct an ultra-sharp view of the galaxy's core.

Read more at Science Daily

Most Recent European Great Ape Discovered

Based on a hominid molar, scientists from Germany, Bulgaria and France have documented that great apes survived in Europe in savannah-like landscapes until seven million years ago.

A seven million year old pre-molar of a hominid discovered near the Bulgarian town of Chirpan documents that great apes survived longer in Europe than previously believed. An international team of scientists from the Bulgarian Academy of Science, the French Centre National de la Recherche Scientifique, and Madelaine Böhme from the Senckenberg Center for Human Evolution and Paleoenvironment at the University of Tübingen was involved in the project. The new discovery may cause a revision in our understanding of some major steps in hominid evolution.

To date scientists have assumed that great apes went extinct in Europe at least 9 million years ago because of changing climatic and environmental conditions. Under the direction of Nikolai Spassov from the National Museum of Natural Science in Sofia, Bulgaria, the molar was discovered in Upper Miocene fluvial sediments near Chirpan. The morphology and the great thickness of the tooth enamel point to a hominid fossil. The age of the fossiliferous sands at 7 million years reveals the fossil to be most recent known great ape from continental Europe.

Until now, the most recent fossil was that of a 9.2 million year old specimen of Ouranopithecus macedonensis from Greece. Hominids therefore were thought to have disappeared from Europe prior to 9 million years ago. At this time, European terrestrial ecosystems had been changed from mostly evergreen and lush forests to savannah-like landscapes with a seasonal climate. It had been thought that great apes, which typically consume fruits, were unable to survive this change due to a seasonal deficiency of fruits.

The scientists found animals typical of a savannah in the fossil-bearing layer: several species of elephants, giraffes, gazelles, antelopes, rhinos, and saber-toothed cats. This discovery suggests that European hominids were able to adapt to the seasonal climate of a savannah-like ecosystem. This conclusion is further corroborated by electron microscope analysis of the tooth's masticatory surface, which reveals that the Bulgarian hominid had consumed hard and abrasive objects like grass, seeds, and nuts. In this respect, the feeding behavior of this animal resembles that of later African hominids from about 4 million years ago (e.g. australopithecids like 'Lucy').

„We now also need to rethink where the origin of humans took place," says Professor Madelaine Böhme of the University of Tübingen. So far, most scientists believe that human evolution happened exclusively in Africa and that humans migrated from Africa to other continents. "There is increasing evidence, however, that a significant part of human evolution happened outside Africa, in Europe and western Asia."

Read more at Science Daily

Scientific Doomsday: Ways the World Could Actually End

2012 is sure to be filled with too many end-of-the-world jokes, and probably a fair amount of genuine fear as well.

But assuming the Mayans were wrong and doomsday isn't on Dec. 21 this year, you may be wondering how the world as we know it might really end. We've collected several scientifically valid scenarios for you to worry about.

Supervolcano

The chances of an earthquake unzipping the world’s fault system are negligible, says seismologist Thorne Lay of the University of California, Santa Cruz.

This is because the energy released by a quake is related to the length of the fault that is ruptured during the event. For example, the 2004 magnitude 9.1 Sumatra quake that triggered the Indian Ocean tsunami and killed nearly 300,000 people, ruptured around 900 miles of a subduction zone fault, the longest ever recorded for a single quake. But the major fault zones that mark boundaries between tectonic plates are not continuous, and irregularities like changes in the type of faulting and the existence of smaller plates with shorter boundaries stop ruptures short of apocalyptic lengths.

But other geologic hazards may have more potential for doom.

“It’s more plausible that you have a truly mammoth eruption,” like an eruption of the supervolcano that lies beneath the Yellowstone National Park area, Lay said. Yellowstone has experienced colossal volcanic explosions in the past, most recently 2 million and 640,000 years ago. Another such mega eruption would be devastating for much of North America, he says.

Giant eruptions have contributed to mass extinctions, including the one that killed off the dinosaurs around 65 million years ago. At that time, volcanoes spewed out a roughly 2,000-foot-deep layer of lava to form part of the 10,000-foot-thick Deccan Traps of India, the world’s largest lava beds, geophysicist Anne-Lise Chenet of the Paris Geophysical Institute wrote in an email. And scientists have also shown that a Siberian volcano may have precipitated the largest extinction on record about 250 million years ago. These blazing behemoths belched out so much sulfur, carbon dioxide and ash that they may have altered the climate enough to collapse the food chain, Lay says.

Yellowstone's giant volcanic crater has risen about 10 inches in the last decade, suggesting molten rock may be building up underneath. During its lifetime, the megavolcano has probably experienced more than a dozen giant eruptions, Lay says. Lately, it’s been blowing off steam through little vents, but it’s unclear whether it’s gearing up for another Earth-shattering blast.

Asteroid Accident

Asteroids typically top the list of extraterrestrial objects that could hit Earth. A 9-mile wide asteroid that crashed into what is now Mexico’s Yucatan Peninsula was partly responsible for the dinosaurs' extinction about 65 million years ago.

The 2004 announcement that 900-foot long Apophis had more than a 2 percent chance of colliding with Earth in 2029 revved up research on asteroid detection and defense, when scientists recalculated the odds down to 1 in 250,000.

Luckily, nothing of that size is in Earth’s path currently, so “we may be safe for at least a few million years,” said planetary scientist Jay Melosh of Purdue University.

But smaller threats may be looming.

NASA expects that roughly every 100 years, an asteroid larger than 55 yards wide will strike. The impact could cause local catastrophes like massive floods, destruction of entire cities and agricultural collapse. Around once every few 100,000 years, chunks of rock more than three-fifths of a mile wide — the equivalent of about 12 New York City blocks — could come tumbling through the atmosphere causing much more serious problems, on a global scale. Acid rain would kill crops, debris would shield Earth from sunlight, and firestorms would ensue, according to NASA’s Near Earth Object Program.

To understand our cosmic risks, scientists are inspecting the solar system to find asteroids that may be heading our way, said UCSC planetary scientist Erik Asphaug. They’ve discovered about 900 of an estimated 1,000 asteroids wider than three-fifths of a mile thought to have an Earth-crossing orbit. None appears to have Earth as its target.

“The plain vanilla odds are very low” that anything already discovered of that size will strike in the near future, Asphaug said. But that doesn’t mean Earth is 100 percent safe.

It’s close to impossible to find every asteroid that could be a threat to Earth.

“There’s always some uncertainty that we’re going to have to live with,” he said. “Or die with.”

Read more at Wired Science

Oldest-Known Astrologer's Board Discovered

A research team has discovered what may be the oldest astrologer's board, engraved with zodiac signs and used to determine a person's horoscope.

Dating back more than 2,000 years, the board was discovered in Croatia, in a cave overlooking the Adriatic Sea. The surviving portion of the board consists of 30 ivory fragments engraved with signs of the zodiac. Researchers spent years digging them up and putting them back together. Inscribed in a Greco-Roman style, they include images of Cancer, Gemini and Pisces.

The board fragments were discovered next to a phallic-shaped stalagmite amid thousands of pieces of ancient Hellenistic (Greek style) drinking vessels.

An ancient astrologer, trying to determine a person's horoscope, could have used the board to show the position of the planets, sun and moon at the time the person was born.

"What he would show the client would be where each planet is, where the sun is, where the moon is and what are the points on the zodiac that were rising and setting on the horizon at the moment of birth," said Alexander Jones, a professor at the Institute for the Study of the Ancient World at New York University. [See Photos of Astrologer's Board]

"This is probably older than any other known example," Jones said. "It's also older than any of the written-down horoscopes that we have from the Greco-Roman world," he said, adding, "we have a lot of horoscopes that are written down as a kind of document on papyrus or on a wall but none of them as old as this."

Jones and StašoForenbaher, a researcher with the Institute for Anthropological Research in Zagreb, reported the discovery in the most recent edition of the Journal for the History of Astronomy.

A 'King Tut experience'

In 1999, the team was digging near the entrance of the Croatian cave, a site well known to archaeologists and people at the nearby hamlet of Nakovana who simply called it "Spila," which means "the cave," Forenbaher told LiveScience.

But what nobody knew at the time was that the cave had a section that had been sealed off more than 2,000 years ago. Forenbaher's girlfriend (now his wife) burrowed through the debris, discovering a wide low passageway that continued in the dark for nearly 33 feet (10 meters). Forenbaher described going through the passageway as "the unique King Tut experience, coming to a place where nobody has been for a couple of thousand years."

Stepping into the cavern "there was a very thin limestone crust on the surface that was cracking under your feet when you went in, which meant that nobody walked there in a very, very, long time," Forenbaher said.

The team would later determine that it had been sealed off in the first century B.C., possibly in response to a military campaign waged against the local people by the Romans.

When the archaeologists investigated they found the phallic-shaped stalagmite, numerous drinking vessels that had been deposited over hundreds of years, and something else. "In the course of that excavation these very tiny bits and pieces of ivory came up," said Forenbaher, "we didn't even realize what we had at the time."

The team went to work. "What followed was years of putting them together, finding more bits and pieces, and figuring out what they were," Forenbaher said. In the end they found themselves staring at the remains of the oldest-known astrologer's board.

How did the board wind up in the cave?

Archaeologists are not certain how the board came to the cave or where it was originally made. Astrology originated in Babylon far back in antiquity, with the Babylonians developing their own form of horoscopes around 2,400 years ago.

Then around 2,100 years ago, astrology spread to the eastern Mediterranean, becoming popular in Egypt, which at the time was under the control of a dynasty of Greek kings.

"It gets modified very much into what we think of as the Greek style of astrology, which is essentially the modern style of astrology," Jones said. "The Greek style is the foundation of astrology that goes through the Middle Ages and into modern Europe, modern India (and) so on."

Radiocarbon dating shows that the ivory used to create the zodiac images dates back around 2,200 years ago, shortly before the appearance of this new form of astrology.

Researchers are not certain where the board was made although Egypt is a possibility. The ivory itself likely came from an elephant that was killed or otherwise died around that time, they suspect. Being a valuable item, the ivory would have been stored for several decades, or even a century, before it was used to construct the zodiac. These signs would then have been attached to a flat (possibly wooden) surface to create the board, which may have included other elements that didn't survive.

At some point it may have been put on a ship heading through the Adriatic Sea, an important route for commerce that the cave overlooks. The people who lived in Croatia at the time were called Illyrians. Although ancient writers tended to have a low opinion of them, archaeological evidence suggests that they interacted with nearby Greek colonies and were very much a part of the Mediterranean world.

It's possible that an astrologer from one of the Greek colonies came to the cave to give a prediction. A consultation held in the flickering light of the cavern would have been a powerful experience, although perhaps not very convenient for the astrologer.

"It doesn't sound like a very practical place for doing the homework for the horoscope like calculating planetary positions," Jones said. [Gallery: Victorian-Era Illustrations of the Heavens]

Another possibility is that the Illyrians traded for or stole the astrology board from someone, not fully understanding what it was used for. The board, along with the drinking vessels, would then have been placed as an offering to a deity worshiped in the cave whose identity is unknown.

"There is definitely a possibility that this astrologer's board showed up as an offering together with other special things that were either bought or plundered from a passing ship," Forenbaher said. He pointed out that the drinking vessels found in the cave were carefully chosen. They were foreign-made, and only a few examples of cruder amphora storage vessels were found with them.

Read more at Discovery News

Jan 16, 2012

Climate Adaptation Difficult for Europe's Birds

For the past 20 years, the climate in Europe has been getting warmer. Species of bird and butterfly which thrive in cool temperatures therefore need to move further north. However, they have difficulty adapting to the warmer climate quickly enough, as shown by new research published in the journal Nature Climate Change.

Åke Lindström is Professor of Animal Ecology at Lund University, Sweden. Together with other European researchers he has looked at 20 years' worth of data on birds, butterflies and summer temperatures. During this period, Europe has become warmer and set temperatures have shifted northwards by 250 km. Bird and butterfly communities have not moved at the same rate.

"Both butterflies and birds respond to climate change, but not fast enough to keep up with an increasingly warm climate. We don't know what the long-term ecological effects of this will be," says Åke Lindström.

Butterflies have adapted more quickly to the changing temperatures and have moved on average 114 km north, whereas birds have only moved 37 km. A likely reason is that butterflies have much shorter lifespans and therefore adapt more quickly to climate change. Because birds like to return to the same breeding ground as in previous years, there is also greater inertia in the bird system.

"A worrying aspect of this is if birds fall out of step with butterflies, because caterpillars and insects in general represent an important source of food for many birds," says Åke Lindström.

Sweden shows the strongest trends with regard to birds; however, there is no corresponding Swedish data for butterflies. For the study, the birds have been divided into 'cold' and 'warm' species, i.e. birds that thrive in slightly cooler or warmer temperatures. For example, chaffinches and reed buntings are 'colder' species and blackcaps and goldfinches 'warmer' species. In general, the researchers have observed that 'warm' birds are on the increase and 'cold' birds are in decline. When new species are seen in an area and others disappear, it is more often 'warm' species that arrive and 'cold' species that disappear.

Read more at Science Daily

Evolution of Complexity Recreated Using 'Molecular Time Travel'

Much of what living cells do is carried out by "molecular machines" -- physical complexes of specialized proteins working together to carry out some biological function. How the minute steps of evolution produced these constructions has long puzzled scientists, and provided a favorite target for creationists.

In a study published early online on January 8, in Nature, a team of scientists from the University of Chicago and the University of Oregon demonstrate how just a few small, high-probability mutations increased the complexity of a molecular machine more than 800 million years ago. By biochemically resurrecting ancient genes and testing their functions in modern organisms, the researchers showed that a new component was incorporated into the machine due to selective losses of function rather than the sudden appearance of new capabilities.

"Our strategy was to use 'molecular time travel' to reconstruct and experimentally characterize all the proteins in this molecular machine just before and after it increased in complexity," said the study's senior author Joe Thornton, PhD, professor of human genetics and evolution & ecology at the University of Chicago, professor of biology at the University of Oregon, and an Early Career Scientist of the Howard Hughes Medical Institute.

"By reconstructing the machine's components as they existed in the deep past," Thornton said, "we were able to establish exactly how each protein's function changed over time and identify the specific genetic mutations that caused the machine to become more elaborate."

The study -- a collaboration of Thornton's molecular evolution laboratory with the biochemistry research group of the University of Oregon's Tom Stevens, professor of chemistry and member of the Institute of Molecular Biology -- focused on a molecular complex called the V-ATPase proton pump, which helps maintain the proper acidity of compartments within the cell.

One of the pump's major components is a ring that transports hydrogen ions across membranes. In most species, the ring is made up of a total of six copies of two different proteins, but in fungi a third type of protein has been incorporated into the complex.

To understand how the ring increased in complexity, Thornton and his colleagues "resurrected" the ancestral versions of the ring proteins just before and just after the third subunit was incorporated. To do this, the researchers used a large cluster of computers to analyze the gene sequences of 139 modern-day ring proteins, tracing evolution backwards through time along the Tree of Life to identify the most likely ancestral sequences. They then used biochemical methods to synthesize those ancient genes and express them in modern yeast cells.

Thornton's research group has helped to pioneer this molecular time-travel approach for single genes; this is the first time it has been applied to all the components in a molecular machine.

The group found that the third component of the ring in Fungi originated when a gene coding for one of the subunits of the older two-protein ring was duplicated, and the daughter genes then diverged on their own evolutionary paths.

The pre-duplication ancestor turned out to be more versatile than either of its descendants: expressing the ancestral gene rescued modern yeast that otherwise failed to grow because either or both of the descendant ring protein genes had been deleted. In contrast, each resurrected gene from after the duplication could only compensate for the loss of a single ring protein gene.

The researchers concluded that the functions of the ancestral protein were partitioned among the duplicate copies, and the increase in complexity was due to complementary loss of ancestral functions rather than gaining new ones.

By cleverly engineering a set of ancestral proteins fused to each other in specific orientations, the group showed that the duplicated proteins lost their capacity to interact with some of the other ring proteins. Whereas the pre-duplication ancestor could occupy five of the six possible positions within the ring, each duplicate gene lost the capacity to fill some of the slots occupied by the other, so both became obligate components for the complex to assemble and function.

"It's counterintuitive but simple: complexity increased because protein functions were lost, not gained," Thornton said. "Just as in society, complexity increases when individuals and institutions forget how to be generalists and come to depend on specialists with increasingly narrow capacities."

The research team's last goal was to identify the specific genetic mutations that caused the post-duplication descendants to functionally degenerate. By reintroducing historical mutations that occurred after the duplication into the ancestral protein, they found that it took only a single mutation from each of the two lineages to destroy the same specific functions and trigger the requirement for a three-protein ring.

"The mechanisms for this increase in complexity are incredibly simple, common occurrences," Thornton said. "Gene duplications happen frequently in cells, and it's easy for errors in copying to DNA to knock out a protein's ability to interact with certain partners. It's not as if evolution needed to happen upon some special combination of 100 mutations that created some complicated new function."

Thornton proposes that the accumulation of simple, degenerative changes over long periods of times could have created many of the complex molecular machines present in organisms today. Such a mechanism argues against the intelligent design concept of "irreducible complexity," the claim that molecular machines are too complicated to have formed stepwise through evolution.

Read more at Science Daily

People Behave Socially and 'Well' Even Without Rules

Millions of human interactions were assessed during the study which included actions such as communication, founding and ending friendships, trading goods, sleeping, moving, however also starting hostilities, attacks and punishment. The game does not suggest any rules and everyone can live with their avatar (i.e. with their "game character" in the virtual world) as they choose. "And the result of this is not anarchy," says Thurner. "The participants organise themselves as a social group with good intents. Almost all the actions are positive."

Exactly how people tick

The interactions were fed into an "alphabet" by the researchers, "similar to how the genetic code of DNA was decoded 15 years ago," says Thurner. "From this we get a pattern which reflects how people tick." However, there is quite a high potential for aggression: so, for example, if a negative action is inflicted, the probability that the player will subsequently also act aggressively shoots up more than tenfold, even to about 30 percent.

Forecasting group dynamic processes in society Thurner and his team were also able to present by means of the pattern that the whole game is a reflection of reality. "For example, we could adopt measured values one for one for communication networks. A further measurement is that almost no one has more than 150 friends, the so-called Dunbar's number, regardless of whether in the real or the virtual world." The study has now been published in the specialist journal PLoS One.

The long-term aim is to detect "phase transitions in societies" early on using these measurements and the behavioural patterns researched in the virtual world in order to be able to forecast group dynamic social processes and to be able to react in the event of these cases in good time. "It is possible, for example, that through certain conditions the aggression level, that has increased tenfold, remains extensively in place and therefore systemically for a longer time, which bears comparison with a drastic radicalisation in societies.

Read more at Science Daily

3,000-Year Old Egyptian 'Lady Gaga' Tomb Found

Swiss archaeologists have discovered the tomb of a female singer -- who may have been the "Lady Gaga" of her time -- dating back almost 3,000 years in Egypt's Valley of the Kings.

The rare find was made accidentally by a team from Switzerland's Basel University headed by Elena Pauline-Grothe and Susanne Bickel in Karnak, near Luxor in Upper Egypt, the Antiquities Minister Mohammed Ibrahim said on Sunday.

The woman, Nehmes Bastet, was a singer for the supreme deity Amon Ra during the Twenty-Second Dynasty (945-712 BC), according to an inscription on a wooden plaque found in the tomb.

She was the daughter of the High Priest of Amon, Ibrahim said.

The discovery is important because "it shows that the Valley of the Kings was also used for the burial of ordinary individuals and priests of the Twenty-Second Dynasty," he added.

The coffin was opened on Monday and Bickel told the BBC that she saw the "nicely wrapped" mummy of the woman who was buried in the tomb.

Bickel said that the upper edge of the tomb was discovered on the first day of the Egyptian revolution on Jan 25, 2011. The discovery was then kept secret and an iron cover was placed over the opening to the tomb.

Read more at Discovery News

Jan 15, 2012

Scientists find fat is the sixth human taste

For generations, scientists thought the human tongue could detect only four basic tastes: sweet, sour, salt and bitter.

Then a fifth was discovered, "umami" or savoury. Now, researchers have identified a previously-unrecognised "sixth taste" – fat.

A team in the United States has located a chemical receptor in the taste buds on the tongue that recognises fat molecules, and found that its sensitivity varies between individuals.

The finding may help to explain why some people consume more fatty foods, as they are less aware of the taste as they eat.

The researchers hope their discovery can be exploited to combat obesity by increasing people's sensitivity to fat in their food.

Apart from the basic tastes, other aspects of food flavour actually come from the smell and are detected in the nose.

The research team, from the school of medicine at Washington University, St Louis, showed that people with more of a receptor called CD36 were better at detecting the presence of fat in food.

They found that variations in a gene that produces CD36 makes people more or less sensitive to the presence of fat.

"The ultimate goal is to understand how our perception of fat in food might influence what foods we eat and the qualities of fat that we consume," said Professor Nada Abumrad, who led the research.

"We've found one potential reason for individual variability in how people sense fat. What we will need to determine in the future is whether our ability to detect fat in foods influences our fat intake, which clearly would have an impact on obesity."

The study, which is published in the Journal of Lipid Research, found that those with half as much CD36 were eight times less sensitive to the presence of fat.

Up to 20 per cent of people are believed to have a variant of the CD36 gene that is associated with producing lower levels of the receptor, which could mean they are less sensitive to the presence of fat in food. This may make them more prone to obesity.

Dr Yanina Pepino, who also conducted the research, added: "If we follow the results in animals, a high-fat diet would lead to less production of CD36, and that, in turn, could make a person less sensitive to fat.

"From our results in this study, we would hypothesise that people with obesity may make less of the CD36 protein.

Read more at The Telegraph

Lunar Reconnaissance Orbiter's LAMP Reveals Lunar Surface Features

New maps produced by the Lyman Alpha Mapping Project aboard NASA's Lunar Reconnaissance Orbiter reveal features at the Moon's northern and southern poles in regions that lie in perpetual darkness. LAMP, developed by Southwest Research Institute® (SwRI®), uses a novel method to peer into these so-called permanently shadowed regions (PSRs), making visible the invisible. LAMP's principal investigator is Dr. Alan Stern, associate vice president of the SwRI Space Science and Engineering Division.

The LAMP maps show that many PSRs are darker at far-ultraviolet wavelengths and redder than nearby surface areas that receive sunlight. The darker regions are consistent with large surface porosities -- indicating "fluffy" soils -- while the reddening is consistent with the presence of water frost on the surface.

"Our results suggest there could be as much as 1 to 2 percent water frost in some permanently shadowed soils," says author Dr. Randy Gladstone, an Institute scientist in the SwRI Space Science and Engineering Division. "This is unexpected because naturally occurring interplanetary Lyman-alpha was thought to destroy any water frost before it could accumulate."

The LAMP team estimates that the loss of water frost is about 16 times slower than previously believed. In addition, the accumulation of water frost is also likely to be highly dependent on local conditions, such as temperature, thermal cycling and even geologically recent "impact gardening" in which micrometeoroid impacts redistribute the location and depth of volatile compounds.

Finding water frost at these new locations adds to a rapidly improving understanding of the Moon's water and related species, as discovered by three other space missions through near-infrared emissions observations and found buried within the Cabeus crater by the LCROSS impactor roughly two years ago. During LRO's nominal exploration mission, LAMP added to the LCROSS results by measuring hydrogen, mercury and other volatile gases ejected along with the water from the permanently shaded soils of the Moon's Cabeus crater.

"An even more unexpected finding is that LAMP's technique for measuring the lunar Lyman-alpha albedo indicates higher surface porosities within PSRs, and supports the long-postulated presence of tenuous 'fairy-castle' like arrangements of surface grains in the PSR soils," says co-author Dr. Kurt Retherford, a senior research scientist also in SwRI's Space Science and Engineering Division.

Comparisons with future LAMP maps created using data gathered from the Moon's day side will prove helpful for revealing more about the presence of water frost, as well as the surface porosities of the darker surface features observed. The LAMP team is also eager to apply the Lyman-alpha technique elsewhere on the Moon and on other solar system objects such as Mercury.

Read more at Science Daily

Body Armor Made From Spider Silk

After decades of trying, scientists may have finally found a way to make body armor out of spider silk.

Aside from being very cool, this would mean ultra-lightweight, super-strong, flexible body armor that would provide highly improved protection for America’s soldiers and law enforcement officers.

Right now, U.S. soldiers must wear very heavy, inflexible and cumbersome body armor for protection. Typically it is hard body armor, a ballistic vest with at least two large, hard ceramic plates, designed to protect the upper body from shrapnel and bullets.

Hard armor basically works by resisting the force of the bullet or shrapnel with the same degree of force. But the more protection hard armor provides, the heavier and more ungainly it becomes. The lowest level protects only against small-caliber projectiles that have less force on impact. Hard-armor design often involves the ability to scale up protection, so there are pockets into which additional plates can be inserted.

Although protection is important -- reports indicate that the risk of death from gunshot is 14 times higher for law enforcement officers who don’t wear armor -- users often find themselves weighing the risk of being shot with the reduction in speed, mobility and agility that hard armor’s weight and unwieldiness can cause.

While soldiers wear hard armor on a daily basis, law enforcement officers in reduced risk situations often prefer the flexibility and lighter weight of soft body armor, which works by spreading out the blunt trauma so that the force is not received in one focused spot. Soft armor often slows down bullet or shrapnel through layers or interwoven fabrics that act like nets or spider webs.

Developing lightweight, flexible soft body armor with the higher degree of protection of hard body armor has so far been the impossible dream.

DuPont’s Kevlar fiber, the soft armor fiber widely adopted by law enforcement, is often described as five times stronger than steel -- but spider silk continues to outperform its artificial counterparts, so the pursuit of Spider-Man style armor has been underway for decades.

Strand-for-strand, researchers in the field know, the drag line of an orb-weaving spider, while weighing far less, can be three times more flexible than Kevlar and five times stronger than steel.

Contrary to its size and weight, spider silk is naturally capable of absorbing a huge amount of energy.

Last year, a team at the Heidelberg Institute For Theoretical Studies in Germany studied the building blocks to the mystery behind what makes spider silk so naturally strong.

There are two key components to spider silk fiber: the soft goo gel that is manufactured in the abdomen and the strong solid thread that it has become when it leaves the body.

This team’s findings, published in Biophysical Journal, suggest that the same components that give the soft goo silk elasticity lead to the stress distribution handy for body armor.

While capitalizing on the natural attributes of spider dragline seems like a no-brainer, the coveted prize of creating spider silk body armor has not been without serious obstacles.

Among the challenges: cracking the genome profile of ideal spider silk; finding a way to synthesize the silk-making protein; and devising a method to mass-manufacture the protein in the volumes necessary.

For a long time, the focus has been on the silk of one of the world’s most lethal spiders -- the black widow, the drag line of which could provide material stronger than Kevlar or steel, and in a far lighter weight and more flexible way.

But farming the spiders has not been an option, as spiders do not play nicely with each other -- they tend to turn into a fight club and fail to produce the mass volumes necessary.

In 2007, scientists at the University of California announced they had identified the black widow silk genes, and they tried injecting it into tomato plants, with the objective that the tomato seed would provide the spider silk.

Tomato plants, crops, bacteria, yeast -- even goats -- have gone in and out of fashion as vehicles for converting the spider silk gel into solid thread.

Enter silkworms. They produce fragile silk, but they have heaps of natural potential as high volume producers capable of spinning approximately a kilometer of silk thread in a few days, with a long history of successful human cultivation.

In Thailand in 1999, the Rajamangala Institute of Technology reported that it had developed body armor using only standard, low-cost silkworm silk. Tests indicated that 16 silk layers could stop a 9mm bullet, and that the vests could provide protection against high-velocity rifle shots as well as .22 caliber handguns.

Read more at Discovery News