Dec 10, 2011

Alzheimer's Antibodies Developed

Researchers at Rensselaer Polytechnic Institute have developed a new method to design antibodies aimed at combating disease. The surprisingly simple process was used to make antibodies that neutralize the harmful protein particles that lead to Alzheimer's disease.

The process is reported in the Dec. 5 Early Edition of the journal Proceedings of the National Academy of Sciences (PNAS). The process, outlined in the paper, titled "Structure-based design of conformation- and sequence-specific antibodies against amyloid β," could be used as a tool to understand complex disease pathology and develop new antibody-based drugs in the future.

Antibodies are large proteins produced by the immune system to combat infection and disease. They are composed of a large Y-shaped protein topped with small peptide loops. These loops bind to harmful invaders in the body, such as a viruses or bacteria. Once an antibody is bound to its target, the immune system sends cells to destroy the invader. Finding the right antibody can determine the difference between death and recovery.

Scientists have long sought methods for designing antibodies to combat specific ailments. However, the incredible complexity of designing antibodies that only attached to a target molecule of interest has prevented scientists from realizing this ambitious goal.

When trying to design an antibody, the arrangement and sequence of the antibody loops is of utmost importance. Only a very specific combination of antibody loops will bind to and neutralize each target. And with billions of different possible loop arrangements and sequences, it is seemingly impossible to predict which antibody loops will bind to a specific target molecule.

The new antibody design process was used to create antibodies that target a devastating molecule in the body: the Alzheimer's protein. The research, which was led by Assistant Professor of Chemical and Biological Engineering Peter Tessier, uses the same molecular interactions that cause the Alzheimer's proteins to stick together and form the toxic particles that are a hallmark of the disease.

"We are actually exploiting the same protein interactions that cause the disease in the brain to mediate binding of antibodies to toxic Alzheimer's protein particles," Tessier said.

Alzheimer's disease is due to a specific protein -- the Alzheimer's protein -- sticking together to form protein particles. These particles then damage the normal, healthy functions of the brain. The formation of similar toxic protein particles is central to diseases such as Parkinson's and mad cow disease.

Importantly, the new Alzheimer's antibodies developed by Tessier and his colleagues only latched on to the harmful clumped proteins and not the harmless monomers or single peptides that are not associated with disease.

Tessier and his colleagues see the potential for their technique being used to target and better understand similar types of protein particles in disorders such as Parkinson's disease.

"By binding to specific portions of the toxic protein, we could test hypotheses about how to prevent or reverse cellular toxicity linked to Alzheimer's disease," Tessier said.

In the long term, as scientists learn more about methods to deliver drugs into the extremely well-protected brain tissue, the new antibody research may also help to develop new drugs to combat disorders such as Alzheimer's disease.

Read more at Science Daily

A 'Wild Card' in Your Genes

The human genome and the endowments of genes in other animals and plants are like a deck of poker cards containing a "wild card" that in a genetic sense introduces an element of variety and surprise that has a key role in life. That's what scientists are describing in a review of more than 100 studies on the topic that appears in ACS Chemical Biology.

Rahul Kohli and colleagues focus on cytosine, one of the four chemical "bases" that comprise the alphabet that the genetic material DNA uses to spell out everything from hair and eye color to risk of certain diseases. But far from just storing information, cytosine has acquired a number of other functions that give it a claim to being the genome's wild card. "In poker, the rules of the game can occasionally change," they note in the article. "Adding a 'wild card' to the mix introduces a new degree of variety and presents opportunities for a skilled player to steal the pot. Given that evolution is governed by the same principles of risk and reward that are common to a poker game, it is perhaps not surprising that a genomic 'wild card' has an integral role in biology."

Read more at Science Daily

Dec 9, 2011

20 Things You Didn't Know About... The Periodic Table

1  You may remember the Periodic Table of the Elements as a dreary chart on your classroom wall. If so, you never guessed its real purpose: It’s a giant cheat sheet.

2  The table has served chemistry students since 1869, when it was created by Dmitry Mendeleyev, a cranky professor at the University of St. Petersburg.

3  With a publisher’s deadline looming, Mendeleyev didn’t have time to describe all 63 then-known elements. So he turned to a data set of atomic weights meticulously gathered by others.

4  To determine those weights, scientists had passed currents through various solutions to break them up into their constituent atoms. Responding to a battery’s polarity, the atoms of one element would go thisaway, the atoms of another thataway. The atoms were collected in separate containers and then weighed.

5  From this process, chemists determined relative weights—which were all Mendeleyev needed to establish a useful ranking.

6  Fond of card games, he wrote the weight for each element on a separate index card and sorted them as in solitaire. Elements with similar properties formed a “suit” that he placed in columns ordered by ascending atomic weight.

7  Now he had a new Periodic Law (“Elements arranged according to the value of their atomic weights present a clear periodicity of properties”) that described one pattern for all 63 elements.

8  Where Mendeleyev’s table had blank spaces, he correctly predicted the weights and chemical behaviors of some missing elements—gallium, scandium, and germanium.

9  But when argon was discovered in 1894, it didn’t fit into any of Mendeleyev’s columns, so he denied its existence—as he did for helium, neon, krypton, xenon, and radon.

10  In 1902 he acknowledged he had not anticipated the existence of these overlooked, incredibly unreactive elements—the noble gases—which now constitute the entire eighth group of the table.

11  Now we sort elements by their number of protons, or “atomic number,” which determines an atom’s configuration of oppositely charged electrons and hence its chemical properties.

12  Noble gases (far right on the periodic table) have closed shells of electrons, which is why they are nearly inert.

13  Atomic love: Take a modern periodic table, cut out the complicated middle columns, and fold it once along the middle of the Group 4 elements. The groups that kiss have complementary electron structures and will combine with each other.

14  Sodium touches chlorine—table salt! You can predict other common compounds like potassium chloride, used in very large doses as part of a lethal injection.

15  The Group 4 elements (shown as IVA above) in the middle bond readily with each other and with themselves. Silicon + silicon + silicon ad infinitum links up into crystalline lattices, used to make semiconductors for computers.

16  Carbon atoms—also Group 4—bond in long chains, and voilà: sugars. The chemical flexibility of carbon is what makes it the key molecule of life.

17  Mendeleyev wrongly assumed that all elements are unchanging. But radioactive atoms have unstable nuclei, meaning they can move around the chart. For example, uranium (element 92) gradually decays into a whole series of lighter elements, ending with lead (element 82).

18  Beyond the edge: Atoms with atomic numbers higher than 92 do not exist naturally, but they can be created by bombarding elements with other elements or pieces of them.

Read more at Discover Magazine

77,000-Year-Old Evidence for 'Bedding' and Use of Medicinal Plants Uncovered at South African Rock Shelter

Researchers have discovered the earliest evidence for the intentional construction of plant "bedding."

An international team of archaeologists, with the participation of Christopher Miller, junior professor at the University of Tübingen, is reporting 77,000-year-old evidence for preserved plant bedding and the use of insect-repelling plants in a rock shelter in South Africa. This discovery is 50,000 years older than earlier reports of preserved bedding and provides a fascinating insight into the behavioural practices of early modern humans in southern Africa.

The team, led by Lyn Wadley of the University of the Witwatersrand, Johannesburg, in collaboration with Christopher Miller (University of Tübingen, Germany), Christine Sievers and Marion Bamford (University of the Witwatersrand), and Paul Goldberg and Francesco Berna (Boston University, USA), is reporting the discovery in the journal Science, available online this week.

The ancient bedding was uncovered during excavations at Sibudu rock shelter (KwaZulu-Natal province, South Africa), where Prof. Wadley has been digging since 1998. At least 15 different layers at the site contain plant bedding, dated between 77,000 and 38,000 years ago. The bedding consists of centimetre-thick layers of compacted stems and leaves of sedges and rushes, extending over at least one square meter and up to three square meters of the excavated area. Christine Sievers, of the University of the Witwatersrand, was able to identify several types of sedges and rushes used in the construction of the bedding.

The oldest evidence for bedding at the site is particularly well-preserved, and consists of a layer of fossilized sedge stems and leaves, overlain by a tissue-paper-thin layer of leaves, identified by botanist Marion Bamford as belonging to Cryptocarya woodii, or River Wild-quince. The leaves of this tree contain chemicals that are insecticidal, and would be suitable for repelling mosquitoes. "The selection of these leaves for the construction of bedding suggests that the inhabitants of Sibudu had an intimate knowledge of the plants surrounding the shelter, and were aware of their medicinal uses. Herbal medicines would have provided advantages for early human health, and the use of insect-repelling plants adds a new dimension to our understanding of human behaviour 77,000 years ago" said Lyn Wadley, honorary professor at the University of the Witwatersrand.

"The inhabitants would have collected the sedges and rushes from along the uThongathi River, located directly below the site, and laid the plants on the floor of the shelter. The bedding was not just used for sleeping, but would have provided a comfortable surface for living and working," said Wadley. Microscopic analysis of the bedding, conducted by Christopher Miller, junior-professor for geoarchaeology at the University of Tübingen, suggests that the inhabitants repeatedly refurbished the bedding during the course of occupation.

The microscopic analysis also demonstrated that after 73,000 years ago, the inhabitants of Sibudu regularly burned the bedding after use. "They lit the used bedding on fire, possibly as a way to remove pests. This would have prepared the site for future occupation and represents a novel use of fire for the maintenance of an occupation site," said Miller.

The preserved bedding is also associated with the remains of numerous fireplaces and ash dumps. Beginning at 58,000 years ago, the number of hearths, bedding and ash dumps increases dramatically. The archaeologists believe that this is a result of increased occupation of the site. In the article, the archaeologists argue that the increased occupation may correspond with changing demographics within Africa at the time. By around 50,000 years ago, modern humans began expanding out of Africa, eventually replacing archaic forms of humans in Eurasia, including the Neanderthals.

This discovery adds to a long list of important finds at Sibudu over the past decade, including perforated seashells, believed to have been used as beads, and sharpened bone points, likely used for hunting. Wadley and others have also presented early evidence from the site for the development of bow and arrow technology, the use of snares and traps for hunting and the production of glue for hafting stone tools.

Read more at Science Daily

Rats Will Help Their Pals Get Free

Lab rats have feelings, too.

Given a choice between munching on a tasty chocolate treat or helping a fellow rat escape from a restraint, test rodents often preferred to liberate a pal in need, indicating that their empathy for others was reward enough.

The observation by University of Chicago neuroscientists, published on Thursday in the journal Science, suggests that even these primitive creatures are wired to show benevolence for their own kind.

"This is the first evidence of helping behavior triggered by empathy in rats," said researcher Jean Decety, professor of psychology and psychiatry at the University of Chicago.

"There are a lot of ideas in the literature showing that empathy is not unique to humans, and it has been well demonstrated in apes, but in rodents it was not very clear."

Researchers started by housing 30 rats together in pairs, each duo sharing the same cage for two weeks. Then, they moved them to a new cage where one rat was held in a restraining device while the other could roam free.

The free rat could see and hear his (or her -- six of the rats were female) trapped buddy, and appeared more agitated while the entrapment was going on.

The door to the trapping enclosure was not easy to open, but most rats figured it out within three to seven days. Once they knew how, they went straight to the door to open it every time they were put in the cage.

To test the rats' true bond to their cagemates, researchers also ran the experiment with toys in the restraint to see if the rats would free the fake stuffed rats like they did their comrades. They did not.

"We are not training these rats in any way," said first author Inbal Ben-Ami Bartal.

"These rats are learning because they are motivated by something internal. We're not showing them how to open the door, they don't get any previous exposure on opening the door, and it's hard to open the door. But they keep trying and trying, and it eventually works."

Even when researchers rearranged the experiment so that the trapped rat would be set free into another enclosure, away from his hero friend, the rats still opened the door, indicating they were not motivated by companionship.

"There was no other reason to take this action, except to terminate the distress of the trapped rats," Bartal said. "In the rat model world, seeing the same behavior repeated over and over basically means that this action is rewarding to the rat."

In one final test to truly measure the resolve of the rats, scientists presented them with a pile of chocolate chips in the cage. The rats were not hungry, and in prior experiments showed they liked chocolate because they would eat it instead of rat chow given the chance.

Still, free rats tended to act benevolently. Even if they munched on a few chips first, they would then free their pal and allow him to eat the remaining chips.

"It said to us that essentially helping their cagemate is on a par with chocolate. He can hog the entire chocolate stash if he want(s) to, and he does not. We were shocked," said co-author Peggy Mason, a professor of neurobiology.

Read more at Discovery News

Don't Miss the Last Total Lunar Eclipse til 2014!

Lunar eclipses are fantastic to experience and, fortunately, they are a whole lot easier to observe than their solar counterparts.

Unlike solar eclipses, you don't need to be in a specific place to see them -- so long as you can see the moon then you can enjoy the eclipse. Also unlike solar eclipses, you don't need any special equipment to observe them.

Well, as luck would have it, in just a few hours, there will be a lunar eclipse for you to feast your eyes on. It takes place on Dec. 10, but if you miss it, the next one isn't until 2014!

Wait a minute, why no lunar eclipses until then? Well, it's all about the orbit of the moon. Let me explain...

We see the moon because it reflects sunlight -- turn the sun off with a magical stellar light switch and the moon would disappear.

As it moves around the Earth, taking approximately a month to complete one orbit, we see differing portions of the illuminated half of the moon; from "new moon" (when we see none of the illuminated half) to "full moon" (when we see it all).

Given that we see a full moon when the sun and moon are opposite to each other from the point of view of the Earth (when Earth is in the middle), you would expect a lunar eclipse every month. But due to the characteristics of the moon's orbit, often an eclipse is not possible.

The orbit of the moon around the Earth is not along the same plane as the orbit of the Earth around the sun, instead it's tilted by a mere 5 degrees. The moon's orbit does cross the orbit of the Earth at two points called the "nodes" -- which means that although the moon is opposite the sun in the sky, it's not exactly opposite and is usually just above or just below the Earth's orbit.

For a total lunar eclipse to occur, the moon must lie at, or very near to, one of these nodes so that it passes through the shadow of the Earth. If it lies a little further away then we might see a partial lunar eclipse where just a portion of the moon passes through Earth's shadow; even further away and no eclipse at all.

It's complicated a little more by the gravity of the sun tugging at the moon and gradually shifting the nodes (known as the Saros Cycle) around the moon's orbit which takes just over 18 years to complete one cycle.

Read more at Discovery News

Dec 8, 2011

Birds Caught in the Act of Becoming a New Species

A study of South American songbirds completed by the Department of Biology at Queen's University and the Argentine Museum of Natural History, has discovered these birds differ dramatically in colour and song yet show very little genetic differences which indicates they are on the road to becoming a new species.

"One of Darwin's accomplishments was to show that species could change, that they were not the unaltered, immutable products of creation," says Leonardo Campagna, a Ph.-D biology student at the Argentine Museum of Natural History in Buenos Aires, who studied at Queen's as part of his thesis. "However it is only now, some 150 years after the publication of his most important work, On the Origin of Species, that we have the tools to begin to truly understand all of the stages that might lead to speciation which is the process by which an ancestral species divides into two or more new species."

For decades scientists have struggled to understand all of the varied forces that give rise to distinct species. Mr. Campagna and his research team studied a group of nine species of South American seedeaters (finches) to understand when and how they evolved.

The study found differences in male reproductive plumage and in some key aspects of the songs that they use to court females. Now, the group is looking to find the genes that underlie these differences, as these so-called candidate genes may well prove to be responsible for the evolution of a new species. This will allow researchers to gain insights into evolution.

"Studies like ours teach us something about what species really are, what processes are involved and what might be lost if these and other species disappear."

Campagna's research co-supervisor is Stephen Lougheed, Acting Director of QUBS and an associate professor in the Department of Biology. QUBS has been a pivotal part of research and teaching at Queen's for more than six decades and hosts researchers from both Canadian and international institutions. Research at QUBS has resulted in more than 800 publications in peer-reviewed journals and more than 200 graduate and undergraduate theses.

Read more at Science Daily

One of the World's Smallest Electronic Circuits Created

A team of scientists, led by Guillaume Gervais from McGill's Physics Department and Mike Lilly from Sandia National Laboratories, has engineered one of the world's smallest electronic circuits. It is formed by two wires separated by only about 150 atoms or 15 nanometers (nm).

The discovery, published in the journal Nature Nanotechnology, could have a significant effect on the speed and power of the ever smaller integrated circuits of the future in everything from smartphones to desktop computers, televisions and GPS systems.

This is the first time that anyone has studied how the wires in an electronic circuit interact with one another when packed so tightly together. Surprisingly, the authors found that the effect of one wire on the other can be either positive or negative. This means that a current in one wire can produce a current in the other one that is either in the same or the opposite direction. This discovery, based on the principles of quantum physics, suggests a need to revise our understanding of how even the simplest electronic circuits behave at the nanoscale.

In addition to the effect on the speed and efficiency of future electronic circuits, this discovery could also help to solve one of the major challenges facing future computer design. This is managing the ever-increasing amount of heat produced by integrated circuits

Well-known theorist Markus Büttiker speculates that it may be possible to harness the energy lost as heat in one wire by using other wires nearby. Moreover, Buttiker believes that these findings will have an impact on the future of both fundamental and applied research in nanoelectronics.

Read more at Science Daily

World Domination From Denver Airport?

Almost no one likes being in airports these days, but some people believe that one airport in particular -- the Denver International Airport -- is not only a hassle but also tied to conspiracies about the collapse of Western civilization.

Some say there’s a top-secret underground bunker for the world’s elite to survive a nuclear war (or the impending Mayan 2012 apocalypse). Others say the airport must have a connection to Nazis since the runways form a perfect swastika (actually they don’t).

Even ex-Minnesota governor Jesse Ventura got into the act, interviewing a man claiming that massive tunnels under the airport were built not for luggage handling or mass transit (that's what they want you to think!), but instead for much more sinister purposes.

On his TV show Conspiracy Theory, Ventura says, "There's a lot of strange things about this airport. It's twenty-five miles from Denver; that's nineteen miles further away from old Stapleton Airport, which seemed to be just fine..." It's not clear why Ventura believes that new airports are always built closer to the nearest city than previous airports, but skeptics are not so sure anything mysterious is going on.

Brian Dunning, host of a podcast called Skeptoid which examines unusual claims from a skeptical, science-based perspective, researched conspiracies about the Denver airport.

He told Discovery News, "It's nearly impossible to summarize the vast number of ordinary events and objects at Denver International Airport that have been misinterpreted, twisted, and sensationalized into 'evidence' for a Zionist New World Order Illuminati conspiracy to control and kill American citizens. There are facets of its planning, its design, its construction, its operational history, and even its artwork that conspiracy theorists point at as proof that we're all doomed."

The airport's artwork?

Yes, perhaps the strangest claim of all is that the conspirators have gone out of their way to announce and describe their evil plans to the world. They say all the signs are there; it's all laid out in front of you, if you just understand how to interpret the clues and signs.

Conspiracy folks point to murals in the airport depicting World War II-era genocide and environmental degradation, along with a message of global unity, peace, and hope. Reading meaning into art is a time-honored tradition, but the conspiracy-minded find messages about Nazis, Mayan 2012 doomsday predictions, global destruction, the collapse of the American government, and even extraterrestrial contact. Conspiracy theorists love to uncover (or fabricate, depending on your point of view) clues to innumerable hidden agendas.

This illogical contradiction is common in conspiracy thinking: It's a carefully-hidden top-secret plot that no one is supposed to know about—except that the conspirators made sure to leave important clues so the public would know about it.

For example, those who believe that NASA didn't go to the moon point out that the moon has no atmosphere -- yet the American flag waves in photos supposedly taken on the moon! Is this proof that the images were shot on a sound stage somewhere, proof that NASA botched their cover-up and left a glaring error betraying their deception? Or maybe NASA and the astronauts intentionally left little clues and hints for the clever conspiracy theorists to reveal? (In fact the reason the flag waves has long since been revealed by many including "The Bad Astronomer" Phil Plait: "It looks like that because of the way the flag was deployed. The flag hangs from a horizontal rod which telescopes out from the vertical one... In other words, the flag looks like it is waving because the astronauts wanted it to look that way.")

Perhaps the most famous case of a conspiracy claiming that the conspirators purposely left clues about a hidden truth was in the late 1960s, when The Beatles guitarist Paul McCartney suddenly died. The remaining Beatles—along with their manager and others—conspired to keep McCartney's death a secret, going so far as to hire a look-alike and sound-alike to take his place in public appearances.

Why? As any good conspiracy theorist worth his salt (or is it sugar? Taste can be deceiving; did anyone have it chemically analyzed?) will tell you, follow the money to reveal the truth: The Beatles were the most popular band in the world, and earning obscene amounts of money for promoters, record companies, merchandisers, and others. McCartney's death could not be allowed to kill this cash cow.

Yet while the conspirators carefully kept the public from finding out about McCartney's death, they also decided that they should reveal the truth in album covers and music.

For example, on the cover of the Abbey Road album, all four Beatles are photographed striding across a zebra crossing—but only McCartney is barefoot. On the cover of Sgt. Pepper’s Lonely Hearts Club Band, McCartney is the only Beatle photographed with a hand over his head, which -- for those smart enough to understand the reference -- is a symbol in some cultures that he was memorialized in death.

Read more at Discovery News

Bleeding Glaciers May Fight Warming

On the remote Norwegian island of Spitsbergen, well inside the Arctic Circle, a deep gash in a dirty-gray glacier gushes like a severed artery (above). Tinted red by a mysterious infusion of dissolved iron, this and other glacial deluges could have a serious impact on coastlines, and even climate, worldwide.

Glaciers all around the globe are melting, and recent studies reveal that small glaciers on Spitsbergen and other Arctic islands are melting fastest of all. By how much that melting ice will raise sea level is an important question, especially as the public comes to terms with new estimates that sea level rise from melting ice will affect tens of millions more people than originally predicted.

Recently, though, researchers have also begun wondering if the demise of ice might actually help combat global warming. That’s where the iron comes in: A big influx of this essential nutrient could remove heat-trapping carbon dioxide from the air by stimulating a bloom of microscopic plants, which lap up CO2 for photosynthesis. That’s precisely the idea behind so-called “iron fertilization” schemes, which require dumping massive loads of iron filings into the sea—and have proven controversial.

So, could melting glaciers fertilize the seas instead? The answer depends on how much iron the melt water contains and how much of it actually gets to parts of the ocean where the nutrient is scarce. It is also important to determine the chemical form of the iron, as not all are created equal. Microscopic plants can readily use some forms of iron and not others.

Recent studies have shown that the iron long known to enter the oceans via rivers and wind-blown dust is not always so bioavailable but that iron in icebergs and glaciers may well be.

“No one has looked at the input of this iron to oceans before,” geochemist Laura Wehrmann told Discovery News. Keen to be the first to do so, she and two colleagues at the University of California, Riverside, braved Spitsbergen’s polar bears and near-freezing temperatures to collect samples this past September. Now, they are busy analyzing them back in the lab.

Here are some other details of their adventure:

Getting to the bleeding glacier that drew researchers to the Far North required a half-day hike across bear territory. To protect against potentially irate bears, one person is required to carry a gun any time researchers mosey away from base camp.

On this trip, the job fell to Wehrmann (above), who was meeting her new postdoctoral fellowship adviser, Tim Lyons, and graduate student Jeremy Owens for the first time face to face. “I was thinking, ‘I hope no polar bear attacks my new boss before I’ve even started working for him!’” Wehrmann recalled.

Read more at Discovery News

Dec 7, 2011

New Tick-Borne Disease Discovered in Sweden

Researchers at the University of Gothenburg's Sahlgrenska Academy have discovered a brand new tick-borne infection. Since the discovery, eight cases have been described around the world, three of them in the Gothenburg area, Sweden.

In July 2009 a 77-year-old man from western Sweden was out kayaking when he went down with acute diarrhea, fever and temporary loss of consciousness. He was taken to hospital where it was found that he was also suffering with deep vein thrombosis (DVT). Following treatment with antibiotics, he was discharged some days later with an anticoagulant to thin his blood. However, the man -- who had an impaired immune system -- went down with a fever again.

Brand new infection

Over the following months the 77-year-old was admitted as an emergency case on several occasions, but despite repeated attempts to find a microbe, and repeated doses of antibiotics, the fever returned. Finally the patient's blood underwent special analysis to look for bacterial DNA -- and that produced results. The findings matched a bacterium in an online gene bank and the results were a sensation: the man had contracted a brand new infection in humans which had never been described in the world before.

Never before seen in Sweden

The man's blood contained DNA that derived with 100% certainty from the bacterium Neoehrlichia mikurensis. This bacterium was identified for the first time in Japan in 2004 in rats and ticks but had never before been seen in Sweden in ticks, rodents or humans.

Christine Wennerås, a doctor and researcher at the Department of Infectious Diseases and the Department of Haematology and Coagulation at the University of Gothenburg's Sahlgrenska Academy, has been studying the case since it first came to light. Last year she was able, for the first time, to describe the newly discovered disease in a scientific article published in the Journal of Clinical Microbiology.

"Since our discovery the bacterium has been reported in eight cases around the world, three of them in Gothenburg," says Wennerås.

Causes DVT

All three of the Gothenburg cases involved patients with an impaired immune system, all of whom became ill during the summer months when ticks are most active.

"The nasty thing about this infection is that it causes DVT, at least in people with an impaired immune system," says Wennerås. "This can be life-threatening. Fortunately, the infection can be treated successfully with antibiotics.

Read more at Science Daily

First Superpredator Had Enormous Eyes on Stalks

The world's first superpredator was a giant crustacean with enormous eyes and a razor sharp mouth, according to a new study in the journal Nature.

The over 3-foot-long marine predator sat at the top of Earth's first food chain, say scientists from the South Australian Museum and the University of Adelaide. They found fossils for the crustacean, named Anomalocaris, at Kangaroo Island, South Australia.

The exceptionally well-preserved fossil eyes for this Cambrian Period crusher reveal the predator had acute vision that would rival or even exceed that of most living insects and crustaceans.

The University of New England's John Paterson, who led the study, and his colleagues explain that Anomalocaris held the #1 spot in the earliest food chain due to its large body size, formidable grasping claws at the front of its head, and a circular mouth with razor-sharp serrations.

Three-feet-long might not seem like that much, but consider the size of other marine animals then. We're talking about some of the world's first animals, after about 100 million years or so of evolution. The oceans included, as they do today, unicellular microscopic organisms as well as creatures like the 1.5-foot-long Hurdia.

Supporting evidence of the predator's dominance includes damage to contemporaneous trilobites, and even its fossilised poo (or coprolites) containing the remains of its prey.

The eyesight of Anomalocaris, now understood thanks to the recent fossil discovery, proves that this marine dweller had superb vision to support its predator lifestyle near what is now  Kangaroo Island. The site dates to 515 million years ago, so it's possible the bug-eyed hunter goes back even earlier in time.

The fossils represent compound eyes. These are the multi-faceted kind seen in arthropods, such as flies, crabs and kin. They are perhaps the largest of their kind to have ever existed, with each eye over 1 inch in length and containing over 16,000 lenses.

The number of lenses and other aspects of their optical design suggest that Anomalocaris would have seen its world with exceptional clarity while hunting in well-lit waters. Only a few arthropods, such as modern predatory dragonflies, have similar resolution.

Read more at Discovery News

Earliest Animals Looked Like Baseballs

Microscopic 570-million-year-old fossils from China may represent the earliest evidence for animal life on Earth, suggests a new study in the Proceedings of the Royal Society B.

Previous theories have said that the fossils represented giant bacteria.

"One of the proponents of the bacteria theory was a co-author of this paper (Jake Bailey of the University of Minnesota) and he now agrees that the fossils do not represent a giant sulfur bacteria," co-author Philip Donoghue, a professor of palaeobiology at the University of Bristol, told Discovery News.

Images previously taken by Shuhai Xiao, a professor of geobiology at Virginia Tech, reveal that many of the fossils from the Dousantuo Formation in South China look like mini baseballs and soccer balls.

With the bacteria hypothesis negated, that leaves a few possibilities as to what these unusual fossils represent. One, argued by Xiao and others, is that the fossils are of metazoan embryos. If so, they would present one of the oldest records of the animal evolutionary lineage.

Another theory is that the fossils are protists, which are unicellular organisms lacking a definite cellular arrangement. Protists include bacteria, algae, diatoms and fungi. Although not animals, early protists may have given rise to the world’s first animals and plants.

To test out the theories, Donoghue and his colleagues focused on the possibility that the sports equipment-looking fossils were bacteria. Living and decayed Thiomargarita, a modern bacteria, were compared with modern embryos.

The researchers used a big particle accelerator in Switzerland to study the fossils down to their most minute details -- just one quarter of a micron. The extreme up-close look revealed that the bacteria and the Doushantuo fossils are indeed very different.

Negation of the bacteria theory now strengthens the argument that the fossils, be they embryos or some kind of protist, sit at the base of the animal tree of life.

Donoghue doesn't think all animal life on Earth emerged from this particular site. The location was "just chance," in terms of preservation.

"It is the most awesome fossil deposit," he said. "Every single grain is a fossil, and the deposit is 8 meters (over 26 feet) thick."

Donoghue explained that there was a lot of dissolved phosphate in the ocean at this now-China location during the Ediacaran Period. The phosphate helped to preserve the fossils over the many millions of years.

He said at least two animals have already been identified at the site, but the finds are very controversial at present. One has been called Vernanimalcula, meaning "small spring animal,” referring to its appearance in the fossil record at the end of what is known as the “Snowball Earth” freeze period.

Jun-Yuan Chen of the Nanjing Institute of Geology and Paleontology at the Chinese Academy of Sciences and his colleagues believe Vernanimalcula is the first known bilateral animal, meaning the first with body symmetry. Donoghue and others, however, dispute that claim.

Read more at Discovery News

Rumors Erupt Over Higgs Boson Discovery

This could be the announcement we've all been waiting for.

As soon as the Large Hadron Collider (LHC) revved up its supercooled electromagnets in 2008 -- which promptly "quenched" (read: broke down in a very expensive way) and then restarted the following year -- it's been the one piece of news the world has been eagerly awaiting: confirmation of the discovery of one of the Universe's most secretive particles -- the Higgs boson.

After gazillions of particle collisions and countless rumors of Higgs discoveries, we have... yet another rumor of a Higgs discovery. But this time, the rumor seems to be meatier than ever.

According to, CERN's Scientific Policy Committee will be meeting on Tuesday (Dec. 13) to discuss, amongst other things, an update on the search for the Higgs boson. Teams from the LHC's ATLAS and CMS experiments will be in attendance.

Interestingly, as noted by the's science correspondent Ian Sample, the head scientists of the two groups will be there to give the Higgs update. "That in itself is telling – usually more junior researchers present updates on the search for the missing particle," Sample pointed out in his Dec. 6 article.

Apart from the heads of ATLAS and CMS being there, why all the excitement?

According to comments left on a number of particle physics blogs, the word is that the LHC is closing in on the Higgs.

The Higgs boson is theorized to be the "force carrier" of the Higgs field -- a field thought to permeate the entire Universe, endowing matter with mass. Only by using powerful particle accelerators like the LHC do we stand a chance of seeing these mysterious particles.

Apparently, both the ATLAS and CMS experiments are independently seeing a Higgs signal, and the predicted mass of the particle agrees with the experimental results. In particle physics-speak, the Higgs appears to have a mass of 125 GeV (giga­electronvolts).

The upshot is that if this is proven, one of physics' bedrock theories -- the Standard Model -- is holding steady. If the Higgs does exist with this mass, then perhaps some more tricky Universal mysteries can be resolved.

If the insider-trading-like rumors are substantiated, the ATLAS detection has been measured to a 3.5-sigma certainty and the CMS result has been measured to a 2.5-sigma certainty. All these "sigmas" may not mean much, but they are a measure of the statistical certainty of a given result.

In an earlier Discovery News article Sean Carroll, senior research associate in the Department of Physics at Caltech, shed some light on what this means.

"Three-sigma events happen occasionally, especially when you look at a lot of data," he said. "But it could be real."

At 3.5-sigma, the ATLAS measurement has a 0.1 percent chance of being a "random fluke." The 2.5-sigma result has a 1 percent chance of being a fluke. With those odds, it's little wonder there's some excitement stirring. However, particle physicists are meticulous about their statistics before going public with any discovery.

"Three-sigma isn't seen as a 'discovery,' but it would be strong evidence for the existence of the Higgs," said Jon Butterworth, an LHC physicist working with the ATLAS detector. "Really, a 'five-sigma' is classed as a discovery. Five-sigma is the 'Gold Standard.'"

Read more at Discovery News

Dec 6, 2011

Baby See, Baby Do? Yes, Unless You Trick Them

Babies love to imitate. Ask any parent and they'll report how infants mimic sounds, facial expressions and actions they observe. Now new research from Concordia University, published in the journal Infant Behavior and Development, has found that infants can even differentiate between credible and non-credible sources. Simply put, most babies won't follow along if they have been previously tricked by an adult.

"Like older children, infants keep track of an individual's history of being accurate or inaccurate and use this information to guide their subsequent learning," says senior researcher Diane Poulin-Dubois, a professor in the Concordia Department of Psychology and member of the Centre for Research in Human Development. "Specifically, infants choose not to learn from someone who they perceive as unreliable."

A group of 60 infants, aged 13 to 16 months, were tested as part of this study. Babies were divided in two groups; with reliable or unreliable testers. In a first task, experimenters looked inside a container, while expressing excitement, and infants were invited to discover whether the box actually contained a toy or was empty. This task was designed to show the experimenter's credibility or lack thereof.

In a second imitation task, the same experimenter used her forehead instead of her hands to turn on a push-on light. The experimenter then observed whether infants would follow suit. The outcome? Only 34 per cent of infants whose testers were unreliable followed this odd task. By contrast, 61 per cent of infants in the reliable group imitated the irrational behavior.

"This shows infants will imitate behaviour from a reliable adult," says second author Ivy Brooker, a PhD student in the Concordia Department of Psychology and member of the Centre for Research in Human Development. "In contrast, the same behaviour performed by an unreliable adult is interpreted as irrational or inefficient, therefore not worth imitating."

Read more at Science Daily

New Horned Dinosaur Announced Nearly 100 Years After Discovery

A new species of horned dinosaur was just announced by an international team of scientists led by Alf Museum staff, 95 years after the initial discovery of the fossil.

The animal, named Spinops sternbergorum, lived approximately 76 million years ago in southern Alberta, Canada.

Spinops was a plant-eater that weighed around two tons when alive, a smaller cousin of Triceratops. A single large horn projected from the top of the nose, and a bony neck frill sported at least two long, backward-projecting spikes as well as two forward-curving hooks. These unique structures distinguish Spinops from related horned dinosaurs.

"I was amazed to learn the story behind these specimens, and how they went unstudied for so long," said Andrew Farke, Augustyn Family Curator of Paleontology at the Raymond M. Alf Museum of Paleontology, and lead author on the study naming Spinops. "This animal is an important addition to our understanding of horned dinosaur diversity and evolution," Farke continued.

Parts of the skulls of at least two Spinops were discovered in 1916 by Charles H. and Levi Sternberg, a father-and-son fossil collecting team. The Sternbergs recognized that their find represented a new species and sent the fossils to The Natural History Museum (London). However, the fossils were deemed too scrappy for exhibit, and consequently were shelved for decades. It wasn't until Farke and colleagues recognized the importance of the fossil that the bones were finally cleaned for study.

"This study highlights the importance of museum collections for understanding the history of our planet," commented Farke. "My colleagues and I were pleasantly surprised to find these fossils on the museum shelf, and even more astonished when we determined that they were a previously unknown species of dinosaur."

The name Spinops sternbergorum (pronounced "SPIN-ops stern-berg-OR-uhm") means "Sternbergs' spine face," referring to the headgear of the animal and honoring the original discoverers of the fossil. Although the face of Spinops is similar to its close relatives Centrosaurus and Styracosaurus, the unique anatomy of the bony neck frill gives scientists better insight into how this structure evolved. In particular, the fossils of Spinops clarify the identification of the long frill spikes common in some horned dinosaurs. Previously, scientists had inferred that these spikes evolved only once in the group.

Read more at Science Daily

Board Games Originated as Elite Pastime

Competitive board games -- played on the ground, on the floor, or on boards -- emerged as pastimes for the elite, with the Roman Empire spreading their popularity throughout Europe, according to a new study.

The study, published in the journal Antiquity, mentions that board games likely originated and disseminated from Egypt and the Fertile Crescent regions at around 3500 B.C. From there, they spread around the Mediterranean before reaching the Roman Empire and what is now Europe.

Based on the archaeological record, board games didn't even reach Britain until the very end of the 1st century B.C. from newly conquered Gaul. At the time, Gaul was a region encompassing present-day France, Belgium, most of Switzerland and other areas.

Not just anyone could play board games then either.

"Many of the first board games appear to have been diplomatic gifts to signify status," co-author Mark Hall told Discovery News. "We have early examples of quite splendid playing pieces belonging to elite, privileged people."

Hall said the world's oldest known board game could be "The Royal Game of Ur," also known as the Game of Twenty Squares. It was discovered in the Royal Tombs of Ur in Iraq. Although no one knows what the earliest rules for the game were, it's thought to have been a predecessor to today's backgammon.

Yet another early game was Senet from predynastic Egypt. Its game board, an example of which was found in King Tutankhamen's tomb, consists of a grid of 30 squares, arranged in three rows of 10. The earliest rules again are a mystery, although different versions of the game are still played today. Another early Egyptian board game, Mehen, featured lion-shaped pieces and marbles.

As the popularity of such games spread, the names often reveal a connection to the Roman Empire. Hall, an historian at the Perth Museum & Art Gallery, and colleague Katherine Forsyth say many derive from the Latin word "tabula," meaning gaming board or counter.

The researchers point out that, in the U.K., no archaeological evidence supports the existence of board games until the first century B.C. One of the most significant finds shortly thereafter of early gaming equipment in Britain, they say, comes from the so-called Doctor's Grave of Stanway in Colchester, England. The grave, dated to 40-50 A.D., contained a gaming board with 26 glass counters, apparently laid out on it as if for play.

"Although the board games followed on the coattails of the Roman conquest of Europe, they came to reflect the cultural and social contexts of particular regions," Hall said.

Early playing pieces from places like Scandinavia and Scotland took on stylistic elements of the cultures of those regions. For example, two face-decorated stone cones were found within a dry stone, hollow-walled structure from the 5th to 7th century A.D. Shetland, Scotland. The anthropomorphized pieces have a distinctly Celtic look.

Bruce Whitehill, founder of the Association of Game & Puzzle Collectors and the inventor of numerous board games, added that the origin of many ancient games may also be traced to China and India.

"The Game of India, one of the most widely played games in the world, is centuries old, though its date of origin is still a matter of speculation," he pointed out.

He continued that "Go," an ancient game from China, "became the national game of Japan and has earned a great following in the United States."

In terms of U.S. history, Whitehill believes "no commercially produced board game has been found in the United States prior to 1822, when two games, "Travelers' Tour Through the United States" and "Travelers' Tour Through Europe" were produced by New York booksellers F. & R. Lockwood.

Read more at Discovery News

Two Record-Breaking Black Hole Behemoths Spotted

How would two recently discovered monster black holes be described? Massive? Supermassive?

Somehow, adding "super" before "massive" is an understatement for the Goliaths living in the centers of the NGC 3842 and NGC 4889 -- two galaxies located 320 million and 335 million light-years away, in the Leo and Coma clusters of galaxies.

A team of astronomers, headed by Nicholas McConnell of the University of California, Berkeley, used data collected by the Hubble Space Telescope, the Keck and Gemini observatories in Hawaii, and the McDonald Observatory in Texas to observe the stars orbiting around the central nuclei of both galaxies and calculated the mass of the black holes hidden in their cores.

By measuring the speed at which these stars were traveling around the invisible mass in the center, an accurate gauge on the black holes' masses could be arrived at.

The research can be found in the Dec. 8 edition of the journal Nature.

Up until this point, the largest known supermassive black hole was living in the center of the elliptical galaxy M87, 54 million light-years from Earth. That heavyweight weighs in at 6.3 billion times the mass of our sun.

As a comparison, the supermassive black hole residing in the center of our galaxy is a positively featherweight 4.3 million solar masses.

So how do the black holes in NGC 3842 and NGC 4889 measure up? Both weigh in at over 9 billion times the mass of our sun. These super-supermassive black holes are over 2,000 times more massive than the supermassive black hole in the center of the Milky Way.

Their event horizons are also huge. The event horizon is the point at which even light cannot escape the black hole's gravitational grasp, and in the case of these two black holes, their event horizons would reach five-times further than the orbit of Pluto from the sun. The event horizon of the Milky Way's piddly black hole is one-fifth the distance from the sun to Mercury.

The existence of black holes with such gargantuan proportions have been long theorized, and are thought to have provided the awesome power behind the quasars that lit up space in the early history of the Universe.

When the Universe was less than half its current age, large quantities of interstellar gas would be drawn into the centers of galaxies, eventually falling into the central black holes, releasing vast quantities of energy in the process. Quasars were born.

However, as the Universe aged, this gas was used in the production of stars -- therefore the fuel supply for quasars dried up.

The quasars may have died in the modern Universe, but the large black hole relics remain behind, lurking silently in the centers of the galaxies they used to terrorize during their "quasar phase."

Although we now know that most galaxies contain supermassive black holes in their cores, none appear to be massive enough to generate the energy the most powerful quasars generated.

But now, with the discovery of two black holes nearing 10 billion solar masses, have astronomers found the missing link? Possibly.

Read more at Discovery News

Dec 5, 2011

When the Heat's On, Some Fish Can Cope

Australian scientists have discovered that some tropical fish have a greater capacity to cope with rising sea temperatures than previously thought -- by adjusting over several generations.

The discovery, by researchers at the ARC Centre of Excellence for Coral Reef Studies, James Cook University and CSIRO sheds a ray of hope amid the rising concern over the future of coral reefs and their fish under the levels of global warming expected to occur by the end of the 21st century.

Understanding the ability of species to acclimatise to rising temperatures over longer time periods is critical for predicting the biological consequences of global warming -- yet it remains one of the least understood aspects of climate science. The scientists were seeking to discover how fish would cope with the elevated sea temperatures expected by 2050 and 2100.

"When we exposed damsel fish to water temperatures 1.5 degrees and 3 degrees above today's, there was a marked decline in their aerobic capacity as we'd expected," explains lead researcher Jennifer Donelson. "This affects their ability to swim fast and avoid predators."

"However when we bred the fish for several generations at higher temperatures, we found that the second generation offspring had almost completely adjusted to the higher temperatures. We were amazed… stunned, even," she says. "It shows that some species can adjust faster than the rate of climate change."

"When one generation of damselfish experiences high temperatures their whole life, the next generation is better able to cope with warmer water. We don't yet fully understand the mechanisms involved, but it doesn't seem to be simple Darwinian selection over a couple of generations," explains team leader Professor Philip Munday.

"Instead, there has been a transmission of information between the generations that enables damselfish to adjust to higher water temperatures."

The two temperatures used in the trial represent likely tropical ocean temperatures at the mid-century and by 2100, based on current trends in carbon dioxide emissions by humanity. A 3 degree increase in tropical ocean temperatures is the temperature predicted to occur if humanity's carbon dioxide emissions continue on their current trajectory.

The unusual finding suggests that some fish may have an innate ability to cope with increased sea temperatures greater than previously thought, the researchers say.

However they caution it applies so far only to a single coral reef fish species, and does not address the more complex issue of the survival of the coral habitat itself, and the effects of warming on plankton in the food chains on which fish depend.

Also, there are likely to be penalties for fish that successfully adapt to higher temperatures, Jennifer Donelson says. Initial observations suggest that the acclimatized offspring are on average smaller than their parents, and we still do not know if they are able to reproduce at the same rate as their predecessors.

Although the experiment has yet to run its full course, the researchers also say they do not expect the fishes' ability to adjust to higher temperatures to continue past 3 degrees.

"At such a level of planetary warming there will be profound changes in Earth's ecosystems, affecting all forms of life, including humans," says Prof. Munday.

However, assuming humans manage to gradually bring global warming under control, it is important to understand how well animals and plants can cope with higher temperatures, in order to manage ecosystems for optimum survival of their species and the services they provide. This research provides an early insight into the adaptive capacity of fish, the team says.

Read more at Science Daily

Deep-Sea Yeti Crab Farms Food on Its Arms

A thousand feet below the surface of the Pacific Ocean, a yeti crab “farms” a colony of bacteria on its claws. To help them grow, it waves its pincers over methane and sulfide vents, fertilizing the bacteria and making them good enough to eat.

The crab is a relatively new species, called Kiwa puravida, and was first discovered in 2006. Biologists from Oregon State University describe the crustacean’s smart farming behavior in the journal PLoS One.

“We watched the crabs wave their claws back and forth in fluid from a methane seep, and rather than trying to capture bacteria, it appeared that they were providing food to the bacteria already growing on their claws,” said lead author of the study, Andrew Thurber, in a press release.

The sun’s light can’t reach this far down into the ocean, so vent and seep animals have to harness chemical energy released from the seafloor. These specialist bacteria are found on deep sea crabs, shrimp and barnacles.

“But we hadn’t before seen that kind of ‘farming’ behavior in which the host waves its symbionts in seep fluid,” says Thurber in the release. “We don’t know for certain whether hydrogen sulfide alone fuels [the bacteria], but we suspect it may use both hydrogen sulfide and methane released from the seafloor to exist so far from the sun.”

Read more at Wired Science

Scienists to Clone Woolly Mammoth

Within 5 years a woolly mammoth will likely be cloned, according to scientists who have just recovered well-preserved bone marrow in a mammoth thigh bone. Japan's Kyodo News first reported the find. You can see photos of the thigh bone at this Kyodo page.

Russian scientist Semyon Grigoriev, acting director of the Sakha Republic's mammoth museum, and colleagues are now analyzing the marrow, which they extracted from the mammoth's femur found in Siberian permafrost soil.

Grigoriev and his team, along with Japan's Kinki University, have announced that they will launch a joint research project next year aimed at recreating the enormous mammal, which went extinct around 10,000 years ago.

Mammoths used to be a common sight on the landscape of North America and Eurasia. One of my favorite papers of recent months concerned the earliest known depiction of an animal from the Americas. It was a mammoth engraved on a mammoth bone. Many of our distant ancestors probably had regular face-to-face encounters with the elephant-like giants.

The key to cloning the woolly mammoth is to replace the nuclei of egg cells from an elephant with those extracted from the mammoth's bone marrow cells. Doing this, according to the researchers, can result in embryos with mammoth DNA. That's actually been known for a while.

What's been missing is woolly mammoth nuclei with undamaged genes. Scientists have been on a Holy Grail type search for such pristine nuclei since the late 1990's. Now it sounds like the missing genes may have been found.

In an odd twist, global warming may be responsible for the breakthrough.

Warmer temperatures tied to global warming have thawed ground in eastern Russia that is almost always permanently frozen. As a result, researchers have found a fair number of well-preserved frozen mammoths there, including the one that yielded the bone marrow.

Read more at Discovery News

Alien Planet Could Host Life

A planet about twice the size of Earth has been confirmed to exist right in the middle of the "habitable zone" around its star, which is much like our own.

Previous research had hinted at the existence of such Earth-like planets, where liquid water could exist, but this is the first time such a life-friendly alien planet has been confirmed.

The planet, known as Kepler-22b, is among 29 confirmed and 2,326 candidate worlds found by a team of astronomers using NASA's Kepler Space Telescope.

Kepler-22b is the smallest planet yet to be found beyond our solar system in the region most conducive to life as we know it on Earth.

"If the greenhouse warming was similar on this planet and if it had a surface, its temperature would be something like 72 degrees Fahrenheit, a very pleasant temperature here on the Earth," William Borucki, lead Kepler researcher at NASA's Ames Research Center in Moffett Field, Calif., said at a press briefing Monday.

The planet is around 2.4 times wider than Earth -- making it a "super-Earth." It takes 289.9 days to fly around its parent star, which is very much like our sun.

"It's almost a solar twin," Batalha said.

More work is needed before scientists will be able to tell if Kepler-22b is rocky like Earth, gaseous like Neptune, or more probably, a mix. But its discovery is a milestone on the road to finding bona fide Earth-like planets.

"We don't know anything about the planets between Earth-size and Neptune-size because in our solar system we have no examples of such planets," said Natalie Batalha, Kepler deputy science team lead at San Jose State University.

The Kepler team's targets also will be scrutinized by the independent SETI Institute, which surveys stars in the Milky Way for non-naturally occurring radio signals, a project known as the Search for Extraterrestrial Intelligence, or SETI.

"There are so many special things about Earth," SETI Institute director Jill Tarter told Discovery News. "We have an example of one. In a physics experiment, when when there are multiple outcomes you want to run that experiment many times. We haven't been able to do those experiments yet. We don't know whether the Earth as it is and life as we know it here -- the way we got here was very unusual, that elsewhere things go in a different way. Or are we common?

"This is a work in progress," she said. "In this field, number two is the all-important number because as soon as we find a different, a separate, an independent example of life somewhere else, we're going to know that it's ubiquitous throughout the universe."

So far, Kepler-22b seems to be flying solo, with no sibling planets, but that conclusion may change. Smaller worlds like Earth require more time for the Kepler team to make observations.

The telescope is staring at about 150,000 stars in the constellations Cygnus and Lyra looking for the miniscule dimming of light that happens when a planet or planets pass across or "transit" -- the stars.

In addition to confirming Kepler-22b, the telescope team discovered more than 1,000 new planet candidates. The recent haul nearly doubles its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host stars.

Read more at Discovery News

Dec 4, 2011

Measuring a Tiny, Yet Mighty, Black Hole

One topic that people always ask astronomers about is black holes. These seemingly mysterious and bizarre objects are known to gobble up everything around them, even light, and physics as we know it cannot accurately describe what goes on inside.

From the outside, however, we consider black holes to be pretty simple objects, described completely by their mass, or size, its spin, and charge. This is often called the "no-hair" theorem of black holes.

For the most part, something that massive is almost certainly neutral, so astronomers really only care about how big a black hole is and how fast it is spinning.

As you might imagine, actually measuring these quantities can be a bit tricky, as by definition, the black hole doesn't give off any light of its own. But researchers are pretty darn clever, and three recent papers detail the precise experiments to measure these quantities with telescopes that range across the electromagnetic spectrum for Cygnus X-1 system. This is a binary system comprised of a black hole and a massive blue giant star.

One of the most difficult quantities to measure in astronomy is the distance to an object. Though we can pinpoint objects on the sky with high accuracy, we can't say much for the actual physics of the object until we know how far away it is.

One of the most basic tools of distance measurement is "trigonometric parallax." This method uses observations of some astronomical object from when the Earth is at different places in its orbit, and a bit of geometry, to figure out the distance to an object.

The geometry behind astronomical parallax. "D" is the distance to the object in question, and "p" is the amount that the object appears to move in the image relative to fixed background objects. 1 AU, or astronomical unit, is the average distance between the Earth and the Sun.

A century ago, optical telescopes like our own 26-inch refractor at the University of Virginia took on the task of mapping the distances to all the nearest stars using trigonometric parallax. The blue star of Cygnus X-1, however, is too distant for parallax to be accurately measured with current optical telescopes. In order to get extremely good precision of measurement on the sky, astronomers turned to a radio telescope the size of the Earth, the Very Long Baseline Array (VLBA).

I love talking about what the VLBA can do, since it seems rather unappreciated for the excellent science that has come from it in the last 20 years. It is comprised of 10 identical radio telescopes spread across North America, and the signals are combined in a way that allows astronomers to map the sky with extremely high precision. Like, milliarcsecond precision. That's like if you held your hand out at arms length and held an atomic nucleus between your thumb and forefinger. If you could see THAT, your vision would be as good as the VLBA's.

So, with such excellent radio vision, astronomers, led by Mark Reid of the Harvard-Smithsonian Center for Astrophysics, tracked the position of Cygnus X-1, specifically the radio emissions from the accretion disk surrounding the black hole, over the course of a year.

They measured the orbital motion, proper motion of the system through the galaxy, and the perceived motion due to parallax, finding it to be a distance of just over 6,060 light years away with an error of less than 10 percent. With the distance in hand, they could now move on to studying the intrinsic properties of the black hole system.

A group led by Jerome Orosz of San Diego State University used data from optical and ultraviolet telescopes to determine the orbital velocity of the blue star around its black hole companion. From this, and knowing the distance, they found the star to be 19 times the mass of the sun and the black hole to be 15 times the mass of the sun.

It may surprise you to think that the star dominates the mass of the binary system, but not by very much. The gravitational pull of the black hole, however, is strong because of the object's very high density as a result of its small radius.

Lijun Gou, also of the Center for Astrophysics, and his collaborators put the final pieces of the puzzle in place with data from several x-ray telescopes.

The accretion disk around the black hole gives off x-ray light with what is called a "soft" spectrum. That is, it is dominated by lower energy x-rays. When in a state where this emission dominates, as opposed to during a flare of some kind, the disk can be modeled fairly simply and the inner radius of that disk measured.

Read more at Discovery News

Psychics and Missing Babies -- Dissecting the Phenomena

Ten-month-old Lisa Irwin went missing October 4 from her home in Kansas City, Missouri, and is presumed to have been kidnapped. The case attracted nationwide attention, sparking an Amber Alert and several massive searches including of the neighborhood and a nearby Kansas landfill -- twice.

Weeks came and went without an arrest, clue, or even a suspect. Enter Stephanie Almaguer, a woman in Dallas, Texas, who claims to be psychic. Almaguer said that information about Baby Lisa's death came to her in a vision, and she sketched the area she saw. That sketch was later circulated to the family, police, and volunteer searchers.

About a week ago dozens of volunteers searched for Baby Lisa in an area roughly described by Almaguer, in some woods near a closed casino about two miles from her parent's home. They found nothing. Almaguer appeared in many media outlets including Fox News. Doug Magditch of KDAF-TV described Almaguer’s involvement in the case—and a strange twist:

    Psychic Stephanie Almaguer says she had an "out-of-body" experience, showing her where to search Lisa Irwin.

 The day 'Baby Lisa' went missing, Almaguer says she had a vision. 

"All of a sudden I felt like I was there," said Almaguer.

 She put pen to paper drawing everything she saw, and posted it on her blog.

" If I don't put it on there and it is important, I may have helped keep somebody lost," said Almaguer. Then, something… unexplainable:

 "The things that I posted, came to happen. The names, everything," said Almaguer.

 The things Almaguer saw exist in Kansas City.

 "It's amazing. You feel like, 'Wow, this baby may be found,'" said Almaguer.

 The post convinced a few dozen people to search the area Saturday. 

"I didn't tell these people where that place was. They told me based on what I had given them," said Almaguer.

Even though everyone admits that the psychic information was wrong (so far anyway), Almaguer and others insist that there must be some validity to her powers because otherwise how could she, without leaving her Texas home, have accurately sketched and described the Kansas City area the volunteers searched? Isn’t this proof of psychic powers?

What Magditch considers “unexplainable” and Almaguer considers “amazing” is in fact quite the opposite if you understand what happened: After Almaguer made the sketch from her vision public, hundreds or thousands of people saw it via her Web site, Facebook page, and other Web sites devoted to missing persons and finding Baby Lisa. Some of those people who were trying to be helpful took Almaguer’s rough sketch and looked for potential matches in and around Kansas City. Almaguer’s description is very vague (including “some kind of tall structure,” “an old crumbling concrete slab foundation,” a “hidden drain or culvert,” etc.) and could match literally hundreds of locations in the region.

Of course Almaguer's information roughly “matched” a location described, photographed, and sent to her by one of her correspondents (where the searchers later looked); that’s the reason it was sent to her in the first place! It’s like posting a photo of your uncle online and asking anyone to send photos of people who look like your uncle; then being amazed when, out of the thousands of potential responses, a few of them look like your uncle.

While it's easy to point out that a psychic was (once again) wrong, the fault is not entirely hers. After all, Almaguer did not actually misdirect police and searchers to the wrong location. She never claimed to know the specific physical location of Baby Lisa -- only to have a rough idea of what the area where the baby might be found might look like (she cautioned that the features on her sketch may be “symbolic” and not literal). The matching of Almaguer's visions to any real location was done by well-meaning but misguided locals, and of course she happily accepted the match as validation of her powers.

Instead of accepting any responsibility for the misinformation, Almaguer insisted that she'd been right all along, posting on her blog complaints about “all the lies, gossip, and hatred surrounding not only me/my participation in trying to help in the Baby Lisa Irwin case, but the hatred towards even my family/children....because people believe [I] was lying about the baby's whereabouts to gain cheap publicity.”

Police said that this is not the first bogus psychic information they have gotten about Baby Lisa; all the others provided bad information as well. This is the second time this year a Texas woman claiming to be psychic has given false information about a murder or crime. In June, a psychic called police describing a horrific scene of mass murder at a ranch outside of Houston, Texas. Police, the FBI, and the Texas Rangers investigated, and it all turned out to be a false alarm. There were no dead bodies; the psychic was wrong.

High-profile psychic failures are nothing new. One of the most recent cases involved Holly Bobo, a young nursing student abducted in rural Tennessee. Bobo was last seen April 13 being led into the woods near her home by a camouflaged individual. Despite extensive police searches and dozens of self-proclaimed psychics offering hundreds of incorrect, vague, and often contradictory tips, neither Bobo nor her abductor have been found. (In fact, police complained that psychics were actually harming the investigation.)

Read more at Discovery News