Aug 31, 2013

Ultracold Big Bang Experiment Successfully Simulates Evolution of Early Universe

Physicists have reproduced a pattern resembling the cosmic microwave background radiation in a laboratory simulation of the big bang, using ultracold cesium atoms in a vacuum chamber at the University of Chicago.

"This is the first time an experiment like this has simulated the evolution of structure in the early universe," said Cheng Chin, professor in physics. Chin and his associates reported their feat in the Aug. 1 edition of Science Express, and it will appear soon in the print edition of Science.

Chin pursued the project with lead author Chen-Lung Hung, PhD'11, now at the California Institute of Technology, and Victor Gurarie of the University of Colorado, Boulder. Their goal was to harness ultracold atoms for simulations of the big bang to better understand how structure evolved in the infant universe.

The cosmic microwave background is the echo of the big bang. Extensive measurements of the CMB have come from the orbiting Cosmic Background Explorer in the 1990s, and later by the Wilkinson Microwave Anisotropy Probe and various ground-based observatories, including the UChicago-led South Pole Telescope collaboration. These tools have provided cosmologists with a snapshot of how the universe appeared approximately 380,000 years following the Big Bang, which marked the beginning of the universe.

It turns out that under certain conditions, a cloud of atoms chilled to a billionth of a degree above absolute zero (-459.67 degrees Fahrenheit) in a vacuum chamber displays phenomena similar to those that unfolded following the big bang, Hung said.

"At this ultracold temperature, atoms get excited collectively. They act as if they are sound waves in air," he said. The dense package of matter and radiation that existed in the very early universe generated similar sound-wave excitations, as revealed by COBE, WMAP and the other experiments.

The synchronized generation of sound waves correlates with cosmologists' speculations about inflation in the early universe. "Inflation set out the initial conditions for the early universe to create similar sound waves in the cosmic fluid formed by matter and radiation," Hung said.

Big bang's rippling echo

The sudden expansion of the universe during its inflationary period created ripples in space-time in the echo of the big bang. One can think of the big bang, in oversimplified terms, as an explosion that generated sound, Chin said. The sound waves began interfering with each other, creating complicated patterns. "That's the origin of complexity we see in the universe," he said.

These excitations are called Sakharov acoustic oscillations, named for Russian physicist Andrei Sakharov, who described the phenomenon in the 1960s. To produce Sakharov oscillations, Chin's team chilled a flat, smooth cloud of 10,000 or so cesium atoms to a billionth of a degree above absolute zero, creating an exotic state of matter known as a two-dimensional atomic superfluid.

Then they initiated a quenching process that controlled the strength of the interaction between the atoms of the cloud. They found that by suddenly making the interactions weaker or stronger, they could generate Sakharov oscillations.

The universe simulated in Chin's laboratory measured no more than 70 microns in diameter, approximately the diameter as a human hair. "It turns out the same kind of physics can happen on vastly different length scales," Chin explained. "That's the power of physics."

The goal is to better understand the cosmic evolution of a baby universe, the one that existed shortly after the big bang. It was much smaller then than it is today, having reached a diameter of only a hundred thousand light years by the time it had left the CMB pattern that cosmologists observe on the sky today.

In the end, what matters is not the absolute size of the simulated or the real universes, but their size ratios to the characteristic length scales governing the physics of Sakharov oscillations. "Here, of course, we are pushing this analogy to the extreme," Chin said.

380,000 years versus 10 milliseconds

"It took the whole universe about 380,000 years to evolve into the CMB spectrum we're looking at now," Chin said. But the physicists were able to reproduce much the same pattern in approximately 10 milliseconds in their experiment. "That suggests why the simulation based on cold atoms can be a powerful tool," Chin said.

None of the Science co-authors are cosmologists, but they consulted several in the process of developing their experiment and interpreting its results. The co-authors especially drew upon the expertise of UChicago's Wayne Hu, John Carlstrom and Michael Turner, and of Stanford University's Chao-Lin Kuo.

Hung noted that Sakharov oscillations serve as an excellent tool for probing the properties of cosmic fluid in the early universe. "We are looking at a two-dimensional superfluid, which itself is a very interesting object. We actually plan to use these Sakharov oscillations to study the property of this two-dimensional superfluid at different initial conditions to get more information."

The research team varied the conditions that prevailed early in the history of the expansion of their simulated universes by quickly changing how strongly their ultracold atoms interacted, generating ripples. "These ripples then propagate and create many fluctuations," Hung said. He and his co-authors then examined the ringing of those fluctuations.

Today's CMB maps show a snapshot of how the universe appeared at a moment in time long ago. "From CMB, we don't really see what happened before that moment, nor do we see what happened after that," Chin said. But, Hung noted, "In our simulation we can actually monitor the entire evolution of the Sakharov oscillations."

Read more at Science Daily

5 Surprising Cultural Facts About Syria

News reports suggest the United States will respond to last week's chemical weapons' attacks in Syria with targeted military strikes.

But despite the looming U.S. involvement and the growing crisis in the region, most Americans know relatively little about the country or its history. From its ancient cities to the current conflict, here are five cultural facts about Syria.

1. The Syrians

About 23 million people live in Syria, and the majority of those people, about 74 percent, are Sunni Muslims. Another 12 percent of the population is made up of Alawites, a sect of Shia Muslims. Despite being a minority, Alawites have dominated the government for decades; President Bashar al-Assad is an Alawite. About 10 percent of the population is Christian, and another small percentage is made up of Druze, a mystical religious sect with elements common to several monotheistic religions.

Whereas most people in Syria speak Arabic, about 9 percent of the population -- mostly in the northeast -- speak Kurdish.

2. Ancient history

Syria has been a cradle of civilization for at least 10,000 years. It was home to the ancient majestic city of Ebla, which flourished from 1800 B.C. to 1650 B.C. A vast trove of 20,000 cuneiform tablets unearthed in the city provided an unprecedented look at everyday life in Mesopotamia at the time. Since then, it has been part of the major empires of history: At various times, the Egyptians, Assyrians, Chaldeans, Persians, Macedonians and Romans ruled the region.

3. Notable places

The biggest cities in the country -- Aleppo, in the northwest, and Damascus, in the southwest -- are truly ancient. Damascus was first mentioned in an Egyptian document dating to 1500 B.C. Carbon dating from archaeological sites near Tell Ramad, just outside of Damascus, suggests that site has been occupied as far back as 6300 B.C.

Aleppo may be one of the oldest continuously occupied cities in the world: There is evidence of human inhabitance of the area from about 6000 B.C., and because the city was along the Silk Road, it saw bustling trade for centuries.

4. Modern history

For nearly four centuries, Syria was part of the Ottoman Empire. Along with what is now Lebanon, Syria came under French control after the Ottoman Empire collapsed in 1918, and became an independent country in 1946. Because the area was once one territory, Syria has traditionally tried to exert influence over Lebanon, and from 1976 to 2005, Syrian troops occupied portions of Lebanon, ostensibly to protect Lebanon from outside threats. (Demonstrations in Lebanon successfully removed Syrian presence in the country after the assassination of Lebanon's Prime Minister Rafic Hariri.)

Hafez al-Assad, the current president's father, was in power from 1971 until his death in 2000. The elder Assad violently squelched dissent and killed thousands of people in a crackdown on the Muslim Brotherhood in 1982. The current president Assad assumed his position after his father's death.

5. Current conflict

The civil war was set in motion after President Bashar al-Assad violently suppressed pro-democracy demonstrations in 2011. Rebel groups began to organize to oust Assad. However, those groups have increasingly been composed of Islamist factions, making the United States wary of assisting them.

In February 2012, several world leaders condemned the massacre by government forces of 300 people in the city of Homs. The United Nations estimates that about 100,000 people have been killed in fighting so far, with millions displaced by the conflict.

In August of last year, President Barack Obama said, "a red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized. That would change my calculus. That would change my equation."

Read more at Discovery News

Aug 30, 2013

Walking Shark Found Strolling in Waters

A walking shark, which uses its fins like legs, has just been discovered taking a stroll off a remote Indonesian island, according to the Indonesian Ministry of Marine Affairs and Fisheries.

Scientists from Conservation International and the Western Australian Museum made the unusual find. Their timing could not have been better.

“The epaulette (long-tailed carpet) shark, Hemiscyllium halmahera, uses its fins to walk across the ocean floor in search of small fish and crustaceans,” Emmeline Johansen of Conservation International’s Asia Pacific Field Division, told Discovery News.

“The discovery comes at a time when Indonesia is significantly ramping up its efforts to protect shark and ray species that are now considered vulnerable to extinction, including whale sharks and manta rays.”

The shark, which sports distinctive spots over most of its narrow body, lives in waters off of the eastern Indonesian island of Halmahera. Females lay small egg cases under coral ledges. The baby sharks hatch, coming into the world small, and generally lead a sedentary life with very limited dispersal.

This species is one of just nine known walking sharks in the entire world. All have very restricted ranges that do not cross deep water. For instance, H. halmahera is found only on Halmahera, H. freycineti is found only in Raja Ampat, and H. galei is located only in Cendrawasih Bay in West Papua.

Six of the nine walking sharks come from Indonesia, a country that’s home to at least 218 overall species of sharks and rays. It also hosts well over 75 percent of the world’s coral species.

The rocky sea floor terrain is no problem for the walking shark, as you can see in this video.

“After nearly three decades as the world’s largest exporter of dried shark fins and other shark and ray products, Indonesia is now focusing on the tremendous economic potential of its sharks and rays as living assets,” Johansen said. “In the last six months’ alone, two of the country’s top marine tourism destinations, Raja Ampat and West Manggarai (home of the famed Komodo National Park) have declared their waters as fully protected shark and ray sanctuaries.”

Read more at Discovery News

'Terror Bird' Was Just a Scary-Looking Vegetarian

Giant prehistoric ‘terror birds’ looked so fierce that many paleontologists assumed they were terrifying predators, but new research finds that the would-be carnivores were probably herbivores.

The terror bird, aka Gastornis, grew to nearly 7 feet tall. It lived between 55 to 40 million years ago in Europe and possessed a huge, sharp beak.

“The terror bird was thought to have used its huge beak to grab and break the neck of its prey, which is supported by biomechanical modeling of its bite force,” Thomas Tütken from the University of Bonn, who led the research, was quoted as saying in a press release. “It lived after the dinosaurs became extinct and at a time when mammals were at an early stage of evolution and relatively small; thus, the terror bird was thought to have been a top predator at that time on land.”

Wrong, according to the latest findings, presented by Tütken and his team at the Goldschmidt conference in Florence this week.

An early clue came by way of footprints likely left behind by an American cousin of Gastornis. The footprints do not show imprints of sharp claws, which would have been expected as tools to grapple prey. Today’s raptors, for example, sport such sharp claws.

Another clue is more obvious — the bird’s hefty size and build. Can you imagine Sesame Street‘s Big Bird (with a big beak) running swiftly after prey? All of that bulk would not make for a very swift hunter. Some researchers theorized that terror birds ambushed prey, but even that seems pretty far-fetched.

To further explore the possibilities, Tütken and colleagues took a geochemical approach. They analyzed the fossilized bones of the birds, focusing on calcium isotope composition. Isotopes are atoms of the same element with different numbers of neutrons.

In prior experiments, the scientists determined that the calcium isotopic composition becomes “lighter” as it passes through the food chain. They tested the method first with herbivorous and carnivorous dinosaurs — including top predator T. rex — as well as mammals living today. For this latest study, they applied the method to terror bird bones housed at the Geiseltal collection at Martin-Luther University in Halle.

They discovered that the calcium isotope compositions of terror bird bones are similar to those of herbivorous mammals and dinosaurs, and not to carnivorous ones.

“Tooth enamel preserves original geochemical signatures much better than bone, but since Gastornis didn’t have any teeth, we’ve had to work with their bones to do our calcium isotope assay,” Tütken explained.

As for many scientific puzzles, the case isn’t completely closed just yet.

“Because calcium is a major proportion of bone — around 40 percent by weight — its composition is unlikely to have been affected much by fossilization,” he said. “However, we want to be absolutely confident in our findings by analyzing known herbivores and carnivores using fossilized bone from the same site and the same time period. This will give us an appropriate reference frame for the terror bird values.”

Read more at Discovery News

Melting Snow Reveals Iron Age Sweater

A boat neck sweater made of warm wool and woven in diamond twill was a dominating fashion trend among reindeer hunters 1,700 years ago, according to researchers who have investigated an extremely well preserved Iron Age tunic found two years ago under melting snow in Norway.

Announced last March, the finding has been detailed in the current issue of the journal Antiquity.

“Due to global warming, rapid melting of snow patches and glaciers is taking place in the mountains of Norway as in other parts of the world, and hundreds of archaeological finds emerge from the ice each year,” Marianne Vedeler, from the University of Oslo, Norway, and Lise Bender Jørgensen, from the Norwegian University of Science and Technology in Trondheim, wrote.

Found in an hunting area on the Norwegian Lendbreen glacier at 6,560 feet above the sea level, the well-preserved tunic was made between 230 and 390 A.D., according to radiocarbon dating.

“It is a very rare item. Complete garments from early first millennium A.D. Europe can be counted on the fingers of one hand,” Bender Jørgensen told Discovery News.

Examinations with a scanning electron microscope and light microscopy revealed that two different fabrics, made of lamb’s wool or wool from adult sheep, are present in the tunic.

“There is no doubt that the wool was carefully chosen for both fabrics, and that both quality and natural pigmentation were taken into consideration,” the researchers said.

Indeed, the fabric was deliberately and evenly mottled, the effect obtained using two light and two dark brown alternating wool threads.

Relatively short and constructed from a simple cut, the greenish-brown tunic would have fitted a slender man about 5 feet, 9 inches tall. It featured a boat neck, had no buttons or fastenings, but was simply drawn over the head like a sweater.

The cut and size of the tunic closely resembles that of a garment excavated more than 150 years ago in a bog at Thorsbjerg, Schleswig-Holsten. Now in the Archaeological Museum in Schleswig, Germany, it was found in an early first millennium weapon deposit offering, and presumably had belonged to an officer.

“The similarity between the two tunics is very interesting as it suggests that a specific style was intended, and that this ‘fashion’ was known over a wide area. Both are woven in a weave called diamond twill that was popular over large parts of northern Europe in the period,” Bender Jørgensen said.

The sweater-like tunic showed hard wear and tear and had been mended with two patches.

“This suggest that the hunter looked after his clothing. He may, however, not have been its first owner,” Bender Jørgensen said.

According to the researchers, it is quite possible that the tunic was originally sleeveless, and that the sleeves were added at the time of the second repair.

“For the first repair the mender used a patch of the same fabric as used in the body section, while the second patch derived from the fabric used for the sleeves. The seams on this second patch are made with the same yarn as used for sewing on the sleeves,” Vedeler and Bender Jørgensen wrote.

Read more at Discovery News

Why Chemical Weapons Cross the 'Red Line'

The United States and other countries are now contemplating military action against the Syrian regime of Bashar Assad, in the wake of an alleged chemical weapons attack last week on a rebel-held area on the outskirts of Damascus. Doctors Without Borders, an international humanitarian organization, says it has treated 3,600 patients for symptoms including convulsions, respiratory difficulties, vision problems and other woes, and that 355 victims already have died.

The Obama Administration, which last year warned the Syrian regime that using chemical weapons would cross a "red line" for unacceptable behavior, now seems to be preparing to inflict punishment upon Assad, probably in the form of an air strike.

But many people are wondering why Assad’s alleged use of chemical weapons is being seen by the United States as the last straw. After all, the Syrian civil war has been raging for more than two years, and 100,000 people already have died, many of them in atrocities that shock the conscience.

Last December, for example, a Syrian air force plane reportedly dropped eight cluster bombs on civilians waiting outside a bakery to buy bread in the small town of Halfaya, slaughtering 68 people.

"Anyone who has actually seen wounds from conventional artillery -- or badly treated body wounds from small arms -- realizes that chemical weapons do not cause more horrible wounds," Anthony Cordesman, an analyst for the Center for Strategic and International Studies, writes in a blog post. He argues that "the case for intervening cannot be based on chemical weapons."

But other experts say that chemical weapons, whose use was banned in warfare by a 1925 international treaty, do indeed cross a line, into a sort of brutality so extreme that the civilized world cannot afford to tolerate it. Because modern armies are equipped with protective gear, chemical weapons tend to be effective only for committing atrocities against helpless civilian populations. And in addition to inflicting excruciating pain upon victims who often die a lingering death, their use has an even more widespread, devastating psychological effect.

"Our minds are hard-wired to be afraid of poisons," explains Charles Blair, a senior fellow with the Federation of American Scientists who teaches graduate courses in biodefense at George Mason University and Johns Hopkins University. "Things that you can’t see or smell or taste are very frightening to people."

The psychological trauma inflicted by chemical warfare was documented in a 2006 study of survivors of the 1980-1988 Iran-Iraq war, one of the few modern conflicts in which militaries used such weapons. Researchers found that nearly 60 percent of subjects who'd been exposed to chemical weapons during the war suffered from post-traumatic stress disorder, about twice the rate of those who had been in the war but avoided chemicals. About 40 percent of the subjects who’d been exposed to chemicals suffered from severe depression, compared to only 12 percent of those without chemical exposure.

Chemicals have been used in warfare since ancient times, when Spartan soldiers burned wood dipped in a mixture of tar and sulfur to create noxious fumes on the battlefield. But it wasn't World War I that armies on both sides began deploying industrially-manufactured poison gases -- such as lung-searing phosgene and chlorine, and mustard gas, which causes blistering when it comes into contact with skin and mucous membranes -- as weapons.

An estimated 90,000 soldiers were killed by gas attacks during the war, and about a million soldiers suffered injuries that often plagued them for the rest of their lives, according to the Organization for the Prohibition of Chemical Weapons, an international monitoring group. In a secret report prepared at the war's end, U.S. Army Lt. Col. C.G. Douglas, a physiologist, concluded that "The particular value of the poison is found in its remarkable casualty-producing power as opposed to its killing power."

Despite their brutal effect, poison gases turned out not to be particularly effective in winning battles, because of their unpredictability.

"During the Great War, they didn't have reliable meteorology," explained John Pike, director of, an Alexandria, Va.-based think tank on military and security issues. "They couldn't necessarily predict that the wind was going to blow the gas in the right or the wrong direction. Temperature and humidity also can change how chemical weapons work. In general, you'd like to be using weapons in a war that are not dependent upon guesses about weather."

The trauma of that war led nations to agree to forgo their use in warfare, but nevertheless, both the United States and the Soviet Union hedged their bets by building vast secret chemical arsenals, possibly as a deterrent against one another. In 1992, the Chemical Weapons Convention, another international treaty, banned nations who signed it from possessing such weapons at all.

The United States, which ratified the treaty in 1997, has since destroyed more than 80 percent of the nearly 30,000 tons of chemical warfare agents from its Cold War arsenal. U.S. forces, however, remain equipped with protective gear against chemical, biological and radioactive threats.

Chemical weapons became obsolete on the battlefield, but repressive regimes have turned to them for a different purpose -- attacks against civilians who lack the training and equipment to protect themselves. In 1988, for example, Iraqi dictator Saddam Hussein unleashed mustard gas and nerve agents sarin, tabun and VX against the Kurdish inhabitants of Halabja, a city in northern Iraq.

As many as 5,000 people died, and grisly photographs of the corpse-strewn city shocked the world.

"They're more of a taboo, because they’ve been effective against civilians," Pike explains. "And because they’ve been used against civilians horrifically."

Blair notes that different sorts of chemical weapons can be used for different purposes. Some poison gases quickly dissipate, allowing government troops to move quickly into an area and seize it. But more persistent gases can be used to keep adversaries out of an area completely.

"The high persistency agents -- remember the creature’s blood in the movie "Alien," how it would go through floors?" he said. "Some of these substances stick around like that."

Read more at Discovery News

Aug 29, 2013

NASA's Chandra Observatory Catches Giant Black Hole Rejecting Material

Astronomers using NASA's Chandra X-ray Observatory have taken a major step in explaining why material around the giant black hole at the center of the Milky Way Galaxy is extraordinarily faint in X-rays. This discovery holds important implications for understanding black holes.

New Chandra images of Sagittarius A* (Sgr A*), which is located about 26,000 light-years from Earth, indicate that less than 1 percent of the gas initially within Sgr A*'s gravitational grasp ever reaches the point of no return, also called the event horizon. Instead, much of the gas is ejected before it gets near the event horizon and has a chance to brighten, leading to feeble X-ray emissions.

These new findings are the result of one of the longest observation campaigns ever performed with Chandra. The spacecraft collected five weeks' worth of data on Sgr A* in 2012. The researchers used this observation period to capture unusually detailed and sensitive X-ray images and energy signatures of super-heated gas swirling around Sgr A*, whose mass is about 4 million times that of the sun.

"We think most large galaxies have a supermassive black hole at their center, but they are too far away for us to study how matter flows near it," said Q. Daniel Wang of the University of Massachusetts in Amherst, who led of a study published Thursday in the journal Science. "Sgr A* is one of very few black holes close enough for us to actually witness this process."

The researchers found that the Chandra data from Sgr A* did not support theoretical models in which the X-rays are emitted from a concentration of smaller stars around the black hole. Instead, the X-ray data show the gas near the black hole likely originates from winds produced by a disk-shaped distribution of young massive stars.

"This new Chandra image is one of the coolest I've ever seen," said co-author Sera Markoff of the University of Amsterdam in the Netherlands. "We're watching Sgr A* capture hot gas ejected by nearby stars, and funnel it in towards its event horizon."

To plunge over the event horizon, material captured by a black hole must lose heat and momentum. The ejection of matter allows this to occur.

"Most of the gas must be thrown out so that a small amount can reach the black hole," said Feng Yuan of Shanghai Astronomical Observatory in China, the study's co-author. "Contrary to what some people think, black holes do not actually devour everything that's pulled towards them. Sgr A* is apparently finding much of its food hard to swallow."

The gas available to Sgr A* is very diffuse and super-hot, so it is hard for the black hole to capture and swallow it. The gluttonous black holes that power quasars and produce huge amounts of radiation have gas reservoirs much cooler and denser than that of Sgr A*.

The event horizon of Sgr A* casts a shadow against the glowing matter surrounding the black hole. This research could aid efforts using radio telescopes to observe and understand the shadow. It also will be useful for understanding the effect orbiting stars and gas clouds may have on matter flowing toward and away from the black hole.

Read more at Science Daily

NASA Data Reveals Mega-Canyon Under Greenland Ice Sheet

Data from a NASA airborne science mission reveals evidence of a large and previously unknown canyon hidden under a mile of Greenland ice.

The canyon has the characteristics of a winding river channel and is at least 460 miles (750 kilometers) long, making it longer than the Grand Canyon. In some places, it is as deep as 2,600 feet (800 meters), on scale with segments of the Grand Canyon. This immense feature is thought to predate the ice sheet that has covered Greenland for the last few million years.

"One might assume that the landscape of the Earth has been fully explored and mapped," said Jonathan Bamber, professor of physical geography at the University of Bristol in the United Kingdom, and lead author of the study. "Our research shows there's still a lot left to discover."

Bamber's team published its findings Thursday in the journal Science.

The scientists used thousands of miles of airborne radar data, collected by NASA and researchers from the United Kingdom and Germany over several decades, to piece together the landscape lying beneath the Greenland ice sheet.

A large portion of this data was collected from 2009 through 2012 by NASA's Operation IceBridge, an airborne science campaign that studies polar ice. One of IceBridge's scientific instruments, the Multichannel Coherent Radar Depth Sounder, can see through vast layers of ice to measure its thickness and the shape of bedrock below.

In their analysis of the radar data, the team discovered a continuous bedrock canyon that extends from almost the center of the island and ends beneath the Petermann Glacier fjord in northern Greenland.

At certain frequencies, radio waves can travel through the ice and bounce off the bedrock underneath. The amount of times the radio waves took to bounce back helped researchers determine the depth of the canyon. The longer it took, the deeper the bedrock feature.

"Two things helped lead to this discovery," said Michael Studinger, IceBridge project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "It was the enormous amount of data collected by IceBridge and the work of combining it with other datasets into a Greenland-wide compilation of all existing data that makes this feature appear in front of our eyes."

The researchers believe the canyon plays an important role in transporting sub-glacial meltwater from the interior of Greenland to the edge of the ice sheet into the ocean. Evidence suggests that before the presence of the ice sheet, as much as 4 million years ago, water flowed in the canyon from the interior to the coast and was a major river system.

Read more at Science Daily

Mysterious Texas 'Blue Dog' Claimed to be Chupacabra

A Texas rancher named Phylis Canion believes that a strange, hairless bluish-skinned animal she discovered on her property in 2007 may be the mythical, vampiric beast called “el chupacabra,” said to be responsible for draining the blood from goats, chickens, and other livestock.

The claims are getting attention because of a new TV series called “The Unexplained Files.”

I investigated Canion’s strange carcass in April 2008 for the “MonsterQuest” TV show and for my book “Tracking the Chupacabra: The Vampire Beast in Fact, Fiction, and Folklore.” In July 2007 Canion began seeing a bluish-gray, hairless animal (actually, three of them) lurking around her ranch, and suspected them of killing over two dozen chickens over several years. Canion said, “Not long after I had seen the first , I came home and there was a chicken dead, but not carried off. It appeared to have all of the blood drained out of it.”

Canion said that whatever attacked her animals was no ordinary predator common to the area, such as a wild dog, bobcat, fox, or coyote. Eventually Canion decided to make it her mission to capture the strange-looking animal, either alive or on videotape.

“I set up a video camera and started filming where the chickens were,” she said.

Still, after weeks and months, the mysterious creature remained elusive. Then on July 14, 2007, Canion got a call from a neighbor telling her a strange animal had been found lying on the road near her ranch. She photographed the carcass, and the animal was unlike any she had ever seen. It had large ears, large fanged teeth, with grayish-blue elephantine skin.

She had it taxidermied and now displays it proudly in her home. It made national news, and many wondered whether she had finally found the elusive chupacabra. To help decide the matter, scientists offered to do genetic testing on the animal.

DNA Testing the “Chupacabra”

DNA testing of the “blue dog” was done by Michael Forstner, Ph.D., a professor in Department of Biology at Texas State University-San Marcos. Forstner described his genetic analysis of the Cuero animal.

“In this case we had the material…I mean, it’s a vertebrate. It’s not going to hard to match this, there are markers for mitochondrial DNA that are easy enough to match against almost any vertebrate on the planet, and those are available on GenBank. So we went to work and indeed that’s pretty much where we ended up…. The sequencing immediately went to the family Canidae, and our immediate concern was that this was going to turn out to be somebody’s pet dog.”

Soon, however, it became clear that it was not a dog when a genetic marker positively identified it as coyote: “We got the sequences back, uniquely within coyote there’s an area of the D-loop, which is the area of mitochondrial DNA… it gives us data on things that are closely related… Uniquely in coyotes there’s a deletion of several bases in one section, and another deletion in another area of an additional seven-base block. Turns out that the sequences that came back had those two unique deletions, and did not match any dogs or wolf. It came back with 97 percent confidence that it was Canis latrans, which is the coyote.”

Canion, expecting that the results would reveal that she had an unknown or unique animal, then commissioned a second DNA test. This one was conducted at a genetics lab at the University of California at Davis; the results were virtually identical to those found by the University of Texas, but with a slightly more specific twist: its mother was a coyote and its father a Mexican wolf. The final answer: Canion’s “blue dog” is just what two separate DNA analyses say it is: a hybrid animal.

Wildlife experts were not surprised; it’s not unusual for dogs, wolves, coyotes and other animals in the canid family to interbreed; in fact scientists and wildlife experts know what a coyote / wolf hybrid looks like; they have been studied for years. These “coywolves” do not suck blood, nor do they have blue skin, nor any of the chupacabra’s unique characteristics.

The Mystery Fades

But what about the weird grayish-blue elephantine skin color? The creature was likely afflicted with a skin diseases caused by mites called sarcoptic mange, which causes its hair to fall out. Since most people rarely see coyotes, dogs, wolves and other animals without fur in advanced stages of mange, the sick creatures can look very strange and mysterious.

As for the claims of blood-drained chickens, that too has a scientific explanation. Just because a dead animal isn’t bloody doesn’t mean that its blood has been drained. Blood will naturally begin to clot and coagulate after the animal dies, creating the appearance of missing blood. The blood of course hasn’t gone anywhere. It has just partly dried up, and the water content has evaporated. Unless the animal is professionally necropsied, it will appear that the carcass has been drained of blood.

Read more at Discovery News

Ancient Mega-Fish No Longer the One that Got Away

For more than a century, the mystery of the true size of a gigantic dinosaur-era fish, Leedsichthys, seemed like the one that got away for paleontologists.

However, a new study may have solved the problem. The study documented an ancient whopper Leedsichthys that may be the largest fish ever found at 16.5 meters (54 feet). The longest living fish, a whale shark, ever documented stretched 12.7 meters (41.5 feet).

The Jurassic giant, Leedsichthys problematicus, received its name because scientists couldn’t estimate the true size of the fish. Fossil hunters uncovered the first Leedsichthys fossils in the late 1800s. The fish’s remains later turned up as far apart as England and Chile.

However, much of the skeleton of Leedsichthys, including the vertebra needed to know the animal’s length, was made of cartilage. Cartilage doesn’t fossilize easily, so paleontologists had to guess from the bones of the skull, gills, fins and a few other parts.

The problem was that the gills of the fish would have grown proportionately larger than the rest of the fish, because of the gills’ need to absorb enough oxygen, according to a 2005 study by Jeff Liston of the National Museums Scotland. Therefore, estimates from the size of the gills couldn’t be trusted.

Liston made Leedsichthys his own Moby Dick and spent a decade tracking down the truth behind the whale of a fish. In 2007, he estimated that most Leedsichthys ranged from seven to twelve meters long. His most recent research may have finally harpooned the ultimate size of the ancient fish.

Liston’s recent study examined fossils from many Leedsichthys, including a particular specimen that he estimates reached 16.5 meters (54 feet). Bone analysis of that Leedsichthys suggest the fish took forty-five years to reach that length.

Leedsichthys grew to 1.6 meters long in their first years. After approximately 20 years, they hit eight to nine meters, according to the new study.

Read more at Discovery News

Aug 28, 2013

Modified Law of Gravity Predicts Dwarf Galaxy Feature Prior to Observations

A modified law of gravity correctly predicted, in advance of the observations, the velocity dispersion -- the average speed of stars within a galaxy relative to each other -- in 10 dwarf satellite galaxies of the Milky Way's giant neighbor Andromeda.

The relatively large velocity dispersions observed in these types of dwarf galaxies is usually attributed to dark matter. Yet predictions made using the alternative hypothesis Modified Newtonian Dynamics (MOND) succeeded in anticipating the observations.

Stacy McGaugh, professor of astronomy at Case Western Reserve, and Mordehai Milgrom, the father of MOND and professor of physics at Weizmann Institute in Israel, report their findings, which have been accepted for publication by the Astrophysical Journal.

The researchers tested MOND on quasi-spherical, very low-surface brightness galaxies that are satellites of Andromeda. In the cosmic scale, they are among the smallest galaxies, containing only a few hundred thousand stars. But with conventional gravity, they are inferred to contain huge amounts of dark matter.

"Most scientists are more comfortable with the dark matter interpretation," McGaugh said. "But we need to understand why MOND succeeds with these predictions. We don't even know how to make this prediction with dark matter."

While this study is very specific, it's part of a broader effort to understand how the universe, the Milky Way and Earth formed and what it's all made of. This informs human understanding of our place in the universe, McGaugh said. Such issues have been of such importance that they've changed religion and philosophy over the centuries, sometimes sending people to be burnt at the stake.

"At stake now is whether the universe is predominantly made of an invisible substance that persistently eludes detection in the laboratory, or whether we are obliged to modify one of our most fundamental theories, the law of gravity," McGaugh continued.

The MOND hypothesis says that Newton's force law must be tweaked at low acceleration -- 11 orders of magnitude lower than what we feel on the surface of Earth. Acceleration above that threshold is linearly proportional to the force of gravity -- as Newton's law says -- but below the threshold, no. At these tiny accelerations, the modified force law resolves the mass discrepancy.

The paper's calculations using MOND also reveal subtle differences in the gravity fields of dwarfs near and far from the host galaxy Andromeda. The gravity fields of dwarfs far from the host appear to be dominated by stars within the dwarf, while the gravity fields of dwarfs close to the host appear to be dominated by the host. No such distinction is expected with dark matter.

"The influence of the host galaxy may provide a test to distinguish between dark matter and MOND," McGaugh says. "Dark matter provides a cocoon for the dwarfs, protecting the stars from tidal influence by the host galaxy. With MOND, the influence of the host is more pronounced."

In a comparison of the predictions calculated using MOND with observations of pairs of similar dwarfs, "the data appears to show MOND's prediction for the influence of the host, but it's fairly subtle," McGaugh said. MOND's predictions of the velocity dispersion were less subtle. These predictions were "really bang on," McGaugh said.

Read more at Science Daily

Tiny Brain Parts Teased from Stem Cells

Ear, eye, liver, windpipe, bladder, and even a heart. The list of body parts grown from stem cells is getting longer and longer. Now add to it one of the most complex organs: the brain.

A team of European scientists has grown parts of a human brain in tissue culture from stem cells. Their work could help scientists understand the origins of schizophrenia or autism and lead to drugs to treat them, said Juergen Knoblich, deputy scientific director at the Institute of Molecular Biotechnology of the Austrian Academy of Science and one of the paper's co-authors.

The advance could also eliminate the need for conducting experiments on animals, whose brains are not a perfect model for humans.

To grow the brain structures, called organoids, the scientists used stem cells, which can develop into any other kind of cell in the body. They put the stem cells into a special solution designed to promote the growth of neural cells. Bits of gel interspersed throughout the solution gave the cells a three-dimensional structure to grown upon. In eight to ten days the stem cells turned into brain cells. After 20 days to a month, the cells matured into a size between three and four millimeters, representing specific brain regions, such as the cortex and the hindbrain.

Growing brain tissue this way marks a major advancement because the lab-grown brain cells self-organized, and took on growth patterns seen in a developing, fetal brain.

Currently, the organoids are limited to how big they can get because they do not have a circulatory system to move around nutrients.

Knoblich's team didn't stop of growing the brain organoids, though. They went a step further and used the developing tissue to study microcephaly, a condition in which the brain stops growing. Microcephalic patients are born with smaller brains, and impaired cognitive development. Studying microcephaly in mice doesn't help because human and mouse brains are too different.

For this part of the study, the researchers used stem cells from a microcephalic patient and grew neurons in a culture. They found that in normal brains have progenitor stem cells that make neurons, and can do so repeatedly. In microcephalic brains, the progenitor cells differentiate into neurons earlier, said Madeline A. Lancaster, the study's lead author. The brain doesn't make as many neurons and a child is born with a much smaller brain volume.

Yoshiki Sasai, a stem-cell biologist at the RIKEN Center for Developmental Biology in Kobe, Japan, garnered headlines last year by growing the precursors to a human eye. "The most important advancement is that they combined this self-organization culture with disease-specific cells to model a genetic disease of human brain malformation," he said.

"Everything we have done with other organs starts with this stage," said Anthony Atala, M.D., the director of the Wake Forest Institute for Regenerative Medicine, who has done yeara of research into using 3-D printers to build organs. Atala was not involved in this study, but he noted that before he could build organs he needed to grow the pieces -- to get the cells to differentiate in just the right way. So though it's unlikely anyone will print brains the way he did a kidney, this kind of experiment is where organ regeneration starts.

Knoblich said the next step is studying other brain disorders, but it will take some time to grow enough brain tissue. One factor is maximum size and how far the brain can develop in the culture. Brain cells develop in layers, and there are several by the time a baby is born. The cortical cells Knoblich's team grew only had one such layer. Another factor is getting blood vessels inside the tissue. That problem could be solved sometime in the future, though he said he couldn't predict when.

Read more at Discovery News

Deep Sea Squid Pretends to Be Tiny...Then Attacks

Deception occurs even in the deepest parts of oceans, as scientists have just discovered that a deep-sea squid pretends to be a small animal, luring prey ever closer before making a deadly attack.

The secret weapon turns out to be a long fishing line-type appendage with a club at the end that the squid waves around like a hand puppet, fooling passers by.

“These tentacle club movements superficially resemble the movements of small marine organisms,” according to Hendrik Hoving, a researcher at the Monterey Bay Aquarium Research Institute, and his team.

Their paper, published in the latest issue of the Proceedings of the Royal Society B, describes the first ever observations of the squid, Grimalditeuthis bonplandi, in its Atlantic and North Pacific habitats. Remotely operated vehicles (ROVs) permitted observation of the squid and other creatures up to nearly 2.5 miles below the ocean surfaces.

Scientists had been puzzled for a while about this particular squid. The tentacles and clubs of most squid bear things like suckers and hooks for catching prey. Most of us have seen B-movies where some enormous squid grabs an unaware diver with these tentacles and gobbles him to bits.

The long elastic stalk of G. bonplandi is instead surprisingly “thin and fragile,” with no such grabbing devices on it. Now we know why.

The ROVs caught the squid in the act of deception.

First, the squid deploys its tentacle club far away from main part of its body. You can see this in part “a” of the image here. The “b” portion of the image shows (with an arrow) pigment-containing cells known as chromatophores. These are very cool, as they create an optical illusion, permitting squid to dramatically change their skin color and texture.

Chromatophores also can reflect light. While sunlight doesn’t reach down into the ocean depths, bioluminescent animals do produce a glow that might be reflected.

The “tr” in the “b” image marks protective membranes on the club that can flap, giving the club its own propulsion.

“These undulatory and flapping movements of the tentacle clubs superficially resemble the swimming of a small midwater animal (e.g. worm, fish, squid, shrimp),” the authors write. “We hypothesize that G. bonplandi exploits this resemblance, using the tentacle clubs to attract potential prey towards the squid. How prey is subsequently engulfed by the arms and handled by the suckers remains subject to speculation.”

Read more at Discovery News

Sun's 8.2-Billion-Year-Old Twin Found

About 250 light-years away in the constellation Capricornus (The Sea Goat) lies a star that looks awfully familiar.

Known as HIP 102152, the star is a virtual twin of our sun, which in and of itself is not so unusual. But HIP 102152 is older than our 4.6-billion-year old sun -- by nearly 4 billion years, making it the oldest solar twin found to date.

"It is important for us to understand our sun in the proper context of stellar astronomy and to identify which of its properties are unique and normal, to predict what its fate may someday be," astronomer TalaWanda Monroe, a postdoctoral fellow at the University of San Paulo in Brazil, wrote in an email to Discovery News.

With human lifespans so limited, seeing the sun in context means astronomers must find stars with similar mass, chemical composition, temperature and other characteristics. From that, they can then extrapolate information about our sun, such as how bright it shined in its youth and how different its radiation may be in the future.

"HIP 102152 is an ideal star to anchor the end of the timeline," Monroe said.

Stars like the sun last about 10 billion years before running out of hydrogen fuel for their thermonuclear reactions. They then cool and expand into what is known as a "red giant" phase.

HIP 102152 may be like the sun in another way as well. Unlike other solar twins, chemical analysis of HIP 102152's light shows a good match to the sun's, including a telltale sign of possible rocky planets.

Scientists found elements common in dust and meteorites missing from HIP 102152's light -- "a strong hint ... that the elements may have gone into making rocky bodies and/or planets" around the star," Monroe wrote.

So far, attempts to search for any orbiting planets have not been successful.

The group also was able to make a direct tie between the amount of lithium in a star and the star’s age.

Some previous studies suggested a low lithium content may indicate the presence of giant planets, said astronomer Jorge Melendez, also with the University of San Paulo.

The new research shows that as a solar-type star ages, its lithium content decreases.

Read more at Discovery News

Aug 27, 2013

Measles-Like Virus May Be Killing Dolphins

From New York to Virginia, dead dolphins have been washing ashore in unusually large numbers this summer. As of Aug. 20, nearly 300 stranded bottlenose dolphins had been reported in the region, according to the National Oceanic and Atmospheric Administration, nearly seven times more than normal in some places.

As experts continue to investigate the cause, the leading contender is an infection called morbillivirus. Related to human measles and canine distemper, the virus seems to cause sporadic epidemics among dolphins. Many years, there are no detected cases, but when the virus hits, it can hit hard. The last epidemic struck off the Atlantic coast in the winter of 1987-88, killing more than 740 animals from New Jersey to Florida.

For now, there is no official announcement to confirm that morbillivirus is the culprit in the current outbreak, though experts involved in the investigation say that the virus has been confirmed in at least some of this year’s stranded dolphins.

“It’s no secret at this point,” said Perry Habecker, a large animal pathologist at the University of Pennsylvania’s School of Veterinary Medicine in New Bolton. His team has been analyzing tissues from dolphins that are washing up in New Jersey. “Morbillivirus is accounting for some of these deaths.”

Every year, at least some dead dolphins wash up onto beaches. Some get hit by boat propellers. Others get caught in fishing nets. Still others succumb to viruses, bacteria, lungworms, fungal infections and other diseases.

From 2007 to 2012, according to NOAA data, between 88 and 113 dolphins washed ashore in the area of the current East Coast die-off. As of last week, the current tally is 299, with a large spike since early July.

In New Jersey, there are usually between half a dozen and dozen strandings each year, said Bob Schoelkopf, founding director of the Marine Mammal Stranding Center in Brigantine, N.J. So far this year, there have been 74 dead dolphins found on the state’s beaches. In Virginia, there were 45 strandings last month, compared to the state’s annual average of just seven in July.

Accidents with boats and commercial fisheries leave telltale signs on dolphin corpses, Schoelkopf said, allowing experts to rule those out as possible explanations for the recent rash of deaths. Water quality and temperature also appear normal this year.

Members of the public have suggested plenty of other possibilities that experts are not taking seriously -- including fall-out from Hurricane Sandy and gas released by the Syrian government.

Instead, the sudden spike in deaths along with preliminary pathology reports and evidence against other explanations suggests that some kind of disease is to blame, and that disease is probably morbillivirus.

“We get a lot of strange calls telling us what people think might be the cause,” Schoelkopf said. “Usually, when dolphins come down with a disease that’s communicable, it spreads easily because they live in such tight-knit family groups of up to a couple hundred animals in a group.”

Among the remaining mysteries -- assuming morbillivirus is the culprit -- scientists still don’t know why or how the disease occasionally causes so much trouble. One possibility is that the virus mutated in a way that made it more virulent, much like the human influenza virus can change some years. Another possibility is that something changed in the dolphin population, making them more susceptible. Or maybe the dolphins caught the virus from a population of pilot whales that swam too close.

Once it infects dolphins, Habecker said, morbillivirus affects multiple body systems and lowers immunity, leading to secondary infections that can kill them. Pneumonia was the ultimate cause of death in some of the dolphins his group has looked at.

Read more at Discovery News

Stone Age Hunters Brought Home the Bacon

Stone Age hunter-gatherers in Europe may have been trading with settled farmers as long as 7,000 years ago -- acquiring pigs to supplement their hauls of wild boar, scientists said Tuesday.

A study in the journal Nature Communications claims to provide the first evidence of live animal trade between the indigenous, nomadic Ertebolle hunters of northern Europe and more advanced, settled farmers who originally came from the Fertile Crescent -- today's Turkey, Syria and Iraq.

"Hunters and farmers were not only acquainted with each other but even traded live animals," said a statement from Germany's Kiel University, which contributed to the study.

Hunter-gatherers and farmers co-existed in northern Europe from about 5,500 to 4,200 BC.

The hunter-gatherers lived off seals and wild boar on the western Baltic coast, while the farmers cultivated crops and livestock south of the Elbe River that runs through central Europe.

The two groups are believed to have made sporadic contact, as suggested by excavated axes and pottery resembling those of the farmers at hunter-gatherer settlements, but the nature and extent of the exchanges remain a mystery.

There has been no previous evidence that the hunters had access to any domestic animals other than dogs.

For the new study, a team analyzed DNA from pig remains unearthed at different Ertebolle settlements. They found the swine had maternal ancestors from the Middle East, like the domestic pigs of their farmer neighbors across the river.

"Members of the Mesolithic (middle Stone Age) Ertebolle culture already had domestic pigs as early as 4,600 B.C., although they were -- as hunters and gatherers -- not yet familiar with animal husbandry," said the statement.

"Ertebolle hunter-gatherers acquired domestic pigs of varying size and coat color, added the study.

Some of the Ertebolle pigs had a light-colored coat with black spots -- a typical feature of domesticated swine and completely different to the inconspicuous grey coat of the wild boar they would have been more familiar with.

The researchers concluded that the two groups likely traded with one another, though they could not rule out livestock theft as a possible explanation.

"Although it is unclear why the Ertebolle sought domestic pigs, both large and small pigs with multicolored coats would likely have seemed strange and exotic compared with the more familiar appearance of the locally available wild boar they traditionally hunted," the team reported.

Read more at Discovery News

Ocean Worm Wriggles Back Into View after 140 Years

In 1873, an unknown species of deep-sea worm was dredged up from the bottom of the ocean. Further analysis showed that the animal, collected from almost 3.5 miles (5.5 kilometers) beneath the surface, turned out to be a new type of acorn worm. It was dubbed Glandiceps abyssicola.

For nearly 140 years, that was the last that humans would see of this type of acorn worm. Acorn worms are a group of animals that live on the seafloor eating pieces of sediment and detritus that float down from above. And the single specimen that was collected in 1873 by the HMS Challenger found its way to Germany, where it was destroyed by bombs in World War II.

Then, in 2009, a small chunk of yellow flesh turned up in a sample of sediment collected near the same spot as the original, in the equatorial Atlantic near South America. An anatomical and genetic study of the material, published last month in the Journal of the Marine Biological Association of the United Kingdom, found that it was part of a Glandiceps abyssicola worm's body.

The main reason that the animal hadn't been spotted since 1873 is that it is very fragile, and tends to fall apart when dredged, said Karen Osborn, a study co-author and worm specialist at the Smithsonian's National Museum of Natural History. The dredging sled runs along the seafloor and knocks items into a net with a chain, which isn't exactly a gentle collecting technique, Osborn told LiveScience. Ideally, the animals are collected with submersibles, where they can be delicately plucked from the ocean bottom, she added.

The deep-sea acorn worms are quite different from their shallow-water relatives, which are more muscular, sturdier and easier to sample, Osborn said. The shallow-water variety also tend to dig burrows and siphon particles from the seafloor. This rediscovered species, however, crawls along the ocean bottom, eating particles of detritus.

"They are like little factories for digesting organic matter," Osborn said.

Read more at Discovery News

Mustard Spiced Ancient European Cuisine

Ancient northern Europeans spiced their venison, seafood and other dishes with tangy mustard seeds. Germany archeologists discovered residues from the garlic mustard (Alliaria petiolata) plant’s seeds in burned leftovers caked onto ceramic pots.

The crust of charred, spicy foods ranged from approximately 6,100 to 3,750 years ago. (And my wife thinks I’m bad about cleaning my dishes promptly!) At that earliest date, domesticated animals had not yet reached the areas on the Baltic Sea coast where the ancient mustard meals were discovered. This may mean Europeans developed the use of spices independently and weren’t just copying practices imported from further south along with livestock, wrote the study authors in the journal PLOS ONE.

Peppery-flavored mustard seeds contain little nutrition, which suggests the spices were being used solely for flavoring. Ancient Europeans seem to have been concerned with the culinary qualities of their cuisine, not just its calories and nutrients, which may mean Stone Age people sought to go beyond simple survival to enjoy the finer things in life.

Identifying ancient spices presented a challenge for the archeologists from the University of Kiel. Most plant material disintegrates easily. However, tiny, durable deposits of silica in the plants, known as phytoliths, provide clues as to which plants people ate long ago. Different species of plants create distinctive phytoliths, so when scientists examine them under a microscope, they can identify which plant was the source of the phytolith.

Read more at Discovery News

Aug 26, 2013

Insight Into the Origin of the Genetic Code

An analysis of enzymes that load amino acids onto transfer RNAs -- an operation at the heart of protein translation -- offers new insights into the evolutionary origins of the modern genetic code, researchers report.

Their findings appear in the journal PLOS ONE.

The researchers focused on aminoacyl tRNA synthetases, enzymes that "read" the genetic information embedded in transfer RNA molecules and attach the appropriate amino acids to those tRNAs. Once a tRNA is charged with its amino acid, it carries it to the ribosome, a cellular "workbench" on which proteins are assembled, one amino acid at a time.

Synthetases charge the amino acids with high-energy chemical bonds that speed the later formation of new peptide (protein) bonds. Synthetases also have powerful editing capabilities; if the wrong amino acid is added to a tRNA, the enzyme quickly dissolves the bond.

"Synthetases are key interpreters and arbitrators of how nucleic-acid information translates into amino-acid information," said Gustavo Caetano-Anollés, a University of Illinois professor of crop sciences and of bioinformatics. Caetano-Anollés, who led the research, also is a professor in the U. of I. Institute for Genomic Biology. "Their editing capabilities are about 100-fold more rigorous than the proofreading and recognition that occurs in the ribosome. Consequently, synthetases are responsible for establishing the rules of the genetic code."

The researchers used an approach developed in the Caetano-Anollés lab to determine the relative ages of different protein regions, called domains. Protein domains are the gears, springs and motors that work together to keep the protein machinery running.

Caetano-Anollés and his colleagues have spent years elucidating the evolution of protein and RNA domains, determining their relative ages by analyzing their utilization in organisms from every branch of the tree of life. The researchers make a simple assumption: Domains that appear in only a few organisms or groups of organisms are likely younger than domains that are more widely employed. The most universally utilized domains -- those that appear in organisms from every branch of the tree of life -- are likely the most ancient.

The researchers used their census of protein domains to establish the relative ages of the domains that make up the synthetases. They found that those domains that load amino acids onto the tRNAs (and edit them when mistakes are made) are more ancient than the domains that recognize the region on the tRNA, called an anticodon, that tells the synthetase which amino acid that tRNA should carry.

"Remarkably, we also found that the most ancient domains of the synthetases were structurally analogous to modern enzymes that are involved in non-ribosomal protein synthesis, and to other enzymes that are capable of making dipeptides," Caetano-Anollés said.

The researchers hypothesize that ancient protein synthesis involved enzymes that looked a lot like today's synthetases, perhaps working in conjunction with ancient tRNAs.

Researchers have known for decades that rudimentary protein synthesis can occur without the involvement of the ribosome, Caetano-Anollés said. But few if any have looked to the enzymes that catalyze these reactions for evidence of the evolutionary origins of protein synthesis.

Alerted to the potential importance of dipeptide formation in early protein synthesis, the researchers next looked for patterns of frequently used dipeptides in the sequences of modern proteins. They focused only on proteins for which scientists have collected the most complete and accurate structural information.

"The analysis revealed an astonishing fact," Caetano-Anollés said. "The most ancient protein domains were enriched in dipeptides with amino acids encoded by the most ancient synthetases. And these ancient dipeptides were present in rigid regions of the proteins."

The domains that appeared after the emergence of the genetic code (which Caetano-Anollés ties to the emergence of the tRNA anticodon) "were enriched in dipeptides that were present in highly flexible regions," he said.

Read more at Science Daily

Time Travel? Don't Forget to Pack Your Wormhole

The concept of a time machine typically conjures up images of an implausible plot device used in a few too many science-fiction storylines. But according to Albert Einstein's general theory of relativity, which explains how gravity operates in the universe, real-life time travel isn't just a vague fantasy.

Traveling forward in time is an uncontroversial possibility, according to Einstein's theory. In fact, physicists have been able to send tiny particles called muons, which are similar to electrons, forward in time by manipulating the gravity around them. That's not to say the technology for sending humans 100 years into the future will be available anytime soon, though.

Time travel to the past, however, is even less understood. Still, astrophysicist Eric W. Davis, of the EarthTech International Institute for Advanced Studies at Austin, argues that it's possible. All you need, he says, is a wormhole, which is a theoretical passageway through space-time that is predicted by relativity.

"You can go into the future or into the past using traversable wormholes," Davis told LiveScience.

Where's My Wormhole?

Wormholes have never been proven to exist, and if they are ever found, they are likely to be so tiny that a person couldn't fit inside, never mind a spaceship.

Even so, Davis' paper, published in July in the American Institute of Aeronautics and Astronautics' journal, addresses time machines and the possibility that a wormhole could become, or be used as, a means for traveling backward in time.

Both general relativity theory and quantum theory appear to offer several possibilities for traveling along what physicists call a "closed, timelike curve," or a path that cuts through time and space -- essentially, a time machine.

In fact, Davis said, scientists' current understanding of the laws of physics "are infested with time machines whereby there are numerous space-time geometry solutions that exhibit time travel and/or have the properties of time machines."

A wormhole would allow a ship, for instance, to travel from one point to another faster than the speed of light -- sort of. That's because the ship would arrive at its destination sooner than a beam of light would, by taking a shortcut through space-time via the wormhole. That way, the vehicle doesn't actually break the rule of the so-called universal speed limit -- the speed of light -- because the ship never actually travels at a speed faster than light.

Theoretically, a wormhole could be used to cut not just through space, but through time as well.

"Time machines are unavoidable in our physical dimensional space-time," David wrote in his paper. "Traversable wormholes imply time machines, and (the prediction of wormholes) spawned a number of follow-on research efforts on time machines."

However, Davis added, turning a wormhole into a time machine won't be easy. "It would take a Herculean effort to turn a wormhole into a time machine. It's going to be tough enough to pull off a wormhole," he told LiveScience.

That's because once a wormhole is created, one or both ends of it would need to be accelerated through time to the desired position, according to general relativity theory.

Challenges Ahead
There are several theories for how the laws of physics might work to prevent time travel through wormholes.

"Not only do we assume (time travel into the past) will not be possible in our lifetime, but we assume that the laws of physics, when fully understood, will rule it out entirely," said Robert Owen, an astrophysicist at Oberlin College in Ohio who specializes in black holes and gravitation theory.

According to scientists' current understanding, keeping a wormhole stable enough to traverse requires large amounts of exotic matter, a substance that is still very poorly understood.

General relativity can't account for exotic matter -- according to general relativity, exotic matter can't exist. But exotic matter does exist. That's where quantum theory comes in. Like general relativity, quantum theory is a system for explaining the universe, kind of like a lens through which scientists observe the universe.

However, exotic matter has only been observed in very small amounts -- not nearly enough to hold open a wormhole. Physicists would have to find a way to generate and harness large amounts of exotic matter if they hope to achieve this quasi-faster-than-light travel and, by extension, time travel.

Furthermore, other physicists have used quantum mechanics to posit that trying to travel through a wormhole would create something called a quantum back reaction.

In a quantum back reaction, the act of turning a wormhole into a time machine would cause a massive buildup of energy, ultimately destroying the wormhole just before it could be used as a time machine.

However, the mathematical model used to calculate quantum back reaction only takes into account one dimension of space-time.

"I am confident that, since (general relativity) theory has not failed yet, that its predictions for time machines, warp drives and wormholes remain valid and testable, regardless of what quantum theory has to say about those subjects," Davis added.

This illustrates one of the key problems in theories of time travel: physicists have to ground their arguments in either general relativity or quantum theory, both of which are incomplete and unable to encompass the entirety of our complex, mysterious universe.

Read more at Discovery News

Deep Sea Mercury Mystery Solved

Predatory fish that feed deeper in the Pacific Ocean, including swordfish, accumulate higher levels of dangerous mercury than piscine predators at the surface, such as yellowfin tuna, but biologists weren’t sure why. Environmental scientists recently uncovered the cause and warned that the threat may increase in the future.

Oceanic bacteria transform the element mercury into toxic methylmercury. At the surface, sunlight destroys up to 80 percent of the methylmercury produced by these bacteria, according to a recent study published in Nature Geoscience. However, in murky waters between 165 to 2,000 feet (50-610 meters) below the ocean’s surface, methylmercury remains in the food web as bacteria devour mercury-contaminated detritus sinking from the surface.

Those bacteria become food for other creatures and mercury thereby spreads through the Pacific’s food web. Methylmercury accumulates higher in the food web because prey pass on mercury contamination to predators, which lack a biological means to dump the poison.

Humans sit at the top of the oceans’ food web and accumulate methylmercury after making lunch of oceanic predators, such as mahi-mahi fish. Mercury itself harms humans, but people face the greatest threat from methylmercury consumption because our bodies lack sufficient defenses against the toxin, according to a U.S. Geological Survey fact sheet. Severe exposure can kill a person, while lower-level doses cause neurological problems, including reduction in motor skills and sensation.

People likely produce the mercury that eventually contaminates seafood.

The mercury entering the Pacific ecosystem bore the chemical signature of pollution from coal plants and other human-related sources. This suggests the mercury menace may increase in the future. Pollution in the winds blowing from Asia onto the Pacific will continue to carry ever-increasing amounts of mercury as the regions’ industrial production and demand for energy increases.

“The implications are that if we’re going to effectively reduce the mercury concentrations in open-ocean fish, we’re going to have to reduce global emissions of mercury, including emissions from places like China and India,” lead author Joel Blum of the University of Michigan said in a press release. “Cleaning up our own shorelines is not going to be enough. This is a global atmospheric problem.”

The rising mercury in thermometers may cause a rise in mercury levels in seafood. Marine biologists have observed an expansion of oxygen-deprived waters below 1,300 feet. Mercury munching bacteria thrive in these oxygen-poor regions. Climate change may be accelerating the expansion of these regions.

Read more at Discovery News

Lunar Water as Old as the Moon

The moon probably had water when it first formed four and a half billion years ago, according to a new study.

Research reported in the journal Nature Geoscience, found evidence of water that was brought to the surface from deep within the lunar mantle by a series of ancient impacts.

"I think it would be very tough to have this water be anywhere other than original to the material that formed the moon," said the study's lead author Rachel Klima of Johns Hopkins University.

"I don't think this was cometary water that was somehow mixed in and excavated back out, or solar wind water. I think this had to be water that was initially there when the materials forming the moon accreted, and what we found supports that idea."

The new water signatures, in the form of hydroxyl molecules, were detected in the central peak of Bullialdus Crater on the moon's near side, according to Klima.

Hydroxyls are molecules consisting of an oxygen atom connected to a hydrogen atom. The pairing is often seen as a substructure of a water molecule.

"Hydroxyls can form when hydrogen in the solar wind flux hits the minerals in the rocks on the lunar surface," said Klima.

"That tends to happen in cooler areas, and there have been signs that it migrates with the lunar day. So basically when it's cooler it will form and stick to the surfaces, and when it gets warmer later in the lunar day it will move."

When Klima first detected hydroxyl in her spectroscopic readings, she assumed it was solar wind generated surface hydroxyls, similar to what had been seen previously.

"But looking at the crater in more detail and at different times during the lunar day, I found there was no change in the hydroxyl signature," said Klima.

Going Deeper

Klima and colleagues were also unable to detect any hydroxyls in the surrounding lunar soil. The only hydroxyls were in the crater's central peak, indicating that it had been dredged up from deep underground.

"It was only in the center of the crater where the rocks from the deepest part of that area had been brought up to the surface, that we saw this hydroxyl signature," said Klima.

Read more at Discovery News

Aug 25, 2013

Quantum Thrusters to Give Warp Drives a Boost?

Warp-drive technology, a form of "faster than light" travel popularized by TV's "Star Trek," could be bolstered by the physics of quantum thrusters -- another science-fiction idea made plausible by modern science.

NASA scientists are performing experiments that could help make warp drive a possibility sometime in the future from a lab built for the Apollo program at NASA's Johnson Space Center in Houston.

A warp-drive-enabled spacecraft would look like a football with two large rings fully encircling it. The rings would utilize an exotic form of matter to cause space-time to contract in front of and expand behind them. Harold "Sonny" White, a NASA physicist, is experimenting with these concepts on a smaller scale using a light-measuring device in the lab.

"We're looking for a change in path length of the photon on the interferometer, because that would be potential evidence that we're generating the effect we're looking for," White told "We've seen, in a couple different experiments with several different analytic techniques, a change in optical-path length. We're making one leg of the interferometer seem a little shorter because of this device being on, versus the device being off. That doesn't mean that it's what we're looking for."

While these results are intriguing, they are in no way definitive proof that warp drive could work, White said. The scaled-down experiments are just a first step toward understanding if these concepts can be taken out of the realm of theory and applied practically.

Quantum Thrust Through Space-Time

Quantum-thruster physics, another technology White is looking into at NASA, could be the key to creating the fuel needed for a warp drive.

These electric "q-thrusters" work as a submarine does underwater, except they're in the vacuum of space, White told the crowd at the Starship Congress on Aug. 17. The spacecraft is theoretically propelled through space by stirring up the cosmic soup, causing quantum-level perturbations. The resulting thrust is similar to that created by a submersible moving through water.

The technology produces negative vacuum energy, a key ingredient for an exotic-matter-powered warp-drive engine.

"The physics models that tell us how to construct a q-thruster are the same models we'll use to generate, design and build a negative vacuum generator," White said. "The quantum thrusters might be a propulsion manifestation of the physics, like the big ring around the spacecraft. If you looked in there, there might be 10,000 of these little cans that are the negative vacuum generators."

White wants to try to apply the quantum-thruster physics models the researchers have been working with in the lab to their work with warp drive.

"We have measured a force in several test devices which is a consequence of perturbing the state of the quantum vacuum," White said. The effect has been small but significant in his experimentation. Going forward, White hopes to do more robust testing to possibly magnify those claims.

Do the Time Warp

The warp-drive ship itself would never be going faster than the speed of light, but the warped space-time around it could help the spacecraft achieve an effective speed of 10 times the speed of light within the confines of White's concept.

When first proposed by Mexican physicist Miguel Alcubierre in 1994, the warp drive would have required huge, unreasonable amounts of energy, but White's work brought those numbers down. Previous studies extrapolated that the drive would need energy equal to the mass energy of Jupiter.

Read more at Discovery News

Isolated Mashco-Piro Indians appear in Peru

Members of an Indian tribe that has long lived in voluntary isolation in Peru's southeastern Amazon attempted to make contact with outsiders for a second time since 2011, leading to a tense standoff at a river hamlet.

Authorities are unsure what provoked the three-day encounter but say the Mashco-Piro may be upset by illegal logging in their territory as well as drug smugglers who pass through. Oil and gas exploration also affects the region.

The more than 100 members of Mashco-Piro clan appeared across the Las Piedras river from the remote community of Monte Salvado in the Tambopata region of Madre de Dios state from June 24-26, said Klaus Quicque, president of the regional FENAMAD indigenous federation.

They asked for bananas, rope and machetes from the local Yine people but were dissuaded from crossing the river by FENAMAD rangers posted at the settlement, said Quicque, who directed them to a banana patch on their side of the river.

The incident on the Las Piedras is chronicled in video shot by one of the rangers and obtained Monday by The Associated Press.

"You can see in the images there was a lot of threatening — the intention of crossing. They practically reached mid-river," Quicque said by phone from Puerto Maldonado, the regional capital.

The video shows Mashco-Piro of all ages and sexes, including men with lances, bows and arrows. In one image shot during a moment of tension, a man flexes his bow, ready to shoot.

Quicque said the estimated 110-150 people living in Monte Salvado "feared for their lives." He credited the ranger, Rommel Ponciano, for keeping a cool head.

He said 23 Mashco-Piro appeared on the first day, 110 on the second and 25 on the third. The clan left and hasn't returned.

"They spoke a variant of Yine," Quicque said, but Ponciano understood only about two-thirds of the words.

The Mashco-Piro live by their own social code, which includes kidnapping other tribes' women and children, according to Carlos Soria, a Lima professor and former head of Peru's park protection agency.

Peruvian law prohibits physical contact with the estimated 15 "uncontacted" tribes in Peru that together are estimated to number between 12,000 and 15,000 people living in jungles east of the Andes. The main reason is their safety: Their immune systems are highly vulnerable to germs other humans carry.

Anthropologist Beatriz Huertas, who works with Peru's agency for indigenous affairs, says the Mashco-Piro are becoming increasingly less isolated. The tribe is believed to number in the hundreds in several different clans.

It is not unusual for them to appear where they did during a season of sparse rainfall when rivers are low, and they tend to be itinerant, she said.

"What's strange is that they came so close to the population of Monte Salvado. It could be they are upset by problems of others taking advantage of resources in their territories and for that reason were demanding objects and food of the population," Huertas said.

Naturalists in the area and national park officials say the tribe's traditional hunting grounds have been affected by a rise in low-flying air traffic related to natural gas and oil exploration in the region.

Quicque said the Mashco-Piro were victimized by "genocide" in the mid-1980s from the incursion of loggers, and subsequently engaged in battles with mahogany-seekers.

Read more at Yahoo! News