More HIV ‘cured’: first a baby, now 14 adults

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A drug-free life beckons for some people with HIV

Two weeks after the revelation that a baby has been “cured” of HIV, reports suggest that a similar treatment can cure some adults too. Early treatment seems crucial, but does not guarantee success.

Asier Sáez-Cirión of the Pasteur Institute’s unit for regulation of retroviral infections in Paris analysed 70 people with HIV who had been treated with antiretroviral drugs (ARVs) between 35 days and 10 weeks after infection – much sooner than people are normally treated.

All of the participants’ drug regimes had been interrupted for one reason or another. For example, some people had made a personal choice to stop taking the drugs, others had been part of a trial of different drug protocols.

Most of the 70 people relapsed when their treatment was interrupted, with the virus rebounding rapidly to pre-treatment levels. But 14 of them – four women and 10 men – were able to stay off of ARVs without relapsing, having taken the drugs for an average of three years.

The 14 adults still have traces of HIV in their blood, but at such low levels that their body can naturally keep it in check without drugs.

On average, the 14 adults have been off medication for seven years. One has gone 10-and-a-half years without drugs. “It’s not eradication, but they can clearly live without pills for a very long period of time,” says Sáez-Cirión.

Last week, a baby was reported to have been “functionally cured” of HIV after receiving a three-drug regime of ARVs almost immediately after birth. Sáez-Cirión warns that rapid treatment doesn’t work for everyone, but the new study reinforces the conclusion that early intervention is important.

“There are three benefits to early treatment,” says Sáez-Cirión. “It limits the reservoir of HIV that can persist, limits the diversity of the virus and preserves the immune response to the virus that keeps it in check.”

Further analysis confirmed that the 14 adults were not “super-controllers” – the 1 per cent of the population that are naturally resistant to HIV – since they lack the necessary protective genes. Also, natural controllers rapidly suppress their infections, whereas these 14 mostly had severe symptoms which led to their early treatment. “Paradoxically, doing badly helped them do better later,” says Sáez-Cirión.

The researchers are trying to identify additional factors that could explain why early intervention only works on some people, hopefully extending the scope for more functional cures.

“This whole area is fascinating, and we’ve been looking very closely at issues of early initiation of treatment, and the potential for functional cures,” says Andrew Ball, senior adviser on HIV/AIDS strategy at the World Health Organization in Geneva.

“The big challenge is identifying people very early in their infection,” says Ball, adding that many people resist testing because of the stigma and potential discrimination. “There’s a good rationale for being tested early, and the latest results may give some encouragement to do that,” he says.

Journal reference: PLoS Pathogens, DOI: 10.1371/journal.ppat.1003211

http://www.newscientist.com/article/dn23276-more-hiv-cured-first-a-baby-now-14-adults.html

Ancient fish had circular-saw jaw

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An ancient fish that sported a saw blade-like whorl of serrated teeth—and was long presumed to be a member of the shark family—actually belonged to a different but closely related group, a new study suggests. Members of the genus Helicoprion were first described in 1899, but fossils have been notoriously incomplete, with most including only spiral groupings of teeth. Although some fossils have also preserved hints of cartilaginous tissue, none have included the braincase or postcranial parts of these fish. Accordingly, scientists never came up with a convincing idea of what these creatures looked like, with some teams suggesting the whorls sprouted from the nose like an elephant’s trunk, and others placing toothy appendages on the creature’s tail, dorsal fins, or drooping from the lower jaw. Now, an x-ray CT scan of a particularly well-preserved fossil unearthed in Idaho in 1950—one that includes 117 teeth, the cartilage on which they were attached, and part of the upper jaw—reveals that the whorl resided within the animal’s lower jaw (artist’s concept above), researchers reported in Biology Letters. The size and shape of the upper jaw fragment suggests that the creature was about 4 meters long, with some other species in the Helicoprion genus measuring almost twice that length. The arrangement of tissues in the animal’s lower jaw, including those previously hidden by the rock that entombs them, definitively shows that Helicoprion is not a shark, the researchers say. Instead, the genus is nestled firmly within a group of cartilaginous fish known as chimaera, a lineage that includes species commonly known as ghost sharks and ratfish.

http://news.sciencemag.org/sciencenow/2013/02/scienceshot-ancient-fish-sported.html?ref=em

Thanks to Dr. Rajadhyaksha for bringing this to the attention of the It’s Interesting community.

Doubts about Johns Hopkins research have gone unanswered, scientist says

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Daniel Yuan, pictured at his home in Laurel, raised doubts for years about the work of his colleagues in a Johns Hopkins medical research lab. “The denial that I am hearing from almost everyone in the group as a consensus is troubling to me,” he wrote in one e-mail. In December 2011, after 10 years at the lab, he was fired.

By Peter Whoriskey
The Washington Post Published: March 11
The numbers didn’t add up.

Over and over, Daniel Yuan, a medical doctor and statistician, couldn’t understand the results coming out of the lab, a prestigious facility at Johns Hopkins Medical School funded by millions from the National Institutes of Health.

He raised questions with the lab’s director. He reran the calculations on his own. He looked askance at the articles arising from the research, which were published in distinguished journals. He told his colleagues: This doesn’t make sense.

“At first, it was like, ‘Okay — but I don’t really see it,’ ” Yuan recalled. “Then it started to smell bad.”

His suspicions arose as reports of scientific misconduct have become more frequent and critics have questioned the willingness of universities, academic journals and the federal government, which pays for much of the work, to confront the problem.

Eventually, the Hopkins research, which focused on detecting interactions between genes, would win wide acclaim and, in a coup for the researchers, space in the pages of Nature, arguably the field’s most prestigious journal. The medical school even issued a news release when the article appeared last year: “Studies Linked To Better Understanding of Cancer Drugs.”

What very few readers of the Nature paper could know, however, was that behind the scenes, Yuan’s doubts seemed to be having profound effects.

In August, Yu-yi Lin, the lead author of the paper, was found dead in his new lab in Taiwan, a puncture mark in his left arm and empty vials of sedatives and muscle relaxants around him, according to local news accounts — an apparent suicide.

And within hours of this discovery, a note was sent from Lin’s e-mail account to Yuan. The e-mail, which Yuan saved, essentially blamed him for driving Lin to suicide. Yuan had written to Nature’s editors, saying that the paper’s results were overstated and that he found no evidence that the analyses described had actually been conducted. On the day of his death, Lin, 38, the father of three young daughters, was supposed to have finished writing a response to Yuan’s criticisms.

The subject line of the e-mail to Yuan, sent by an unknown person, said “your happy ending.”

“Yu-yi passed away this morning. Now you must be very satisfied with your success,” the e-mail said.

Yuan said he was shocked by the note, so much so that he began to shake.

But in the seven months since, he has wondered why no one — not the other investigators on the project, not the esteemed journal, not the federal government — has responded publicly to the problems he raised about the research.

The passions of scientific debate are probably not much different from those that drive achievement in other fields, so a tragic, even deadly dispute might not be surprising.

But science, creeping ahead experiment by experiment, paper by paper, depends also on institutions investigating errors and correcting them if need be, especially if they are made in its most respected journals.

If the apparent suicide and Yuan’s detailed complaints provoked second thoughts about the Nature paper, though, there were scant signs of it.

The journal initially showed interest in publishing Yuan’s criticism and told him that a correction was “probably” going to be written, according to e-mail rec­ords. That was almost six months ago. The paper has not been corrected.

The university had already fired Yuan in December 2011, after 10 years at the lab. He had been raising questions about the research for years. He was escorted from his desk by two security guards.

More recently, a few weeks after a Washington Post reporter began asking questions, a university spokeswoman said that a correction had been submitted to Nature and that it was under review.

“Your questions will be addressed with that publication,” a spokeswoman for the Hopkins medical school, Kim Hoppe, wrote in an e-mail.

Neither the journal nor the university would disclose the nature of the correction.

Hoppe declined an opportunity to have university personnel sit for interviews.

In the meantime, the paper has been cited 11 times by other published papers building on the findings.

It may be impossible for anyone from outside to know the extent of the problems in the Nature paper. But the incident comes amid a phenomenon that some call a “retraction epidemic.”

Last year, research published in the Proceedings of the National Academy of Sciences found that the percentage of scientific articles retracted because of fraud had increased tenfold since 1975.

The same analysis reviewed more than 2,000 retracted biomedical papers and found that 67 percent of the retractions were attributable to misconduct, mainly fraud or suspected fraud.

“You have a lot of people who want to do the right thing, but they get in a position where their job is on the line or their funding will get cut, and they need to get a paper published,” said Ferric C. Fang, one of the authors of the analysis and a medical professor at the University of Washington. “Then they have this tempting thought: If only the data points would line up . . . ”

Fang said retractions may be rising because it is simply easier to cheat in an era of digital images, which can be easily manipulated. But he said the increase is caused at least in part by the growing competition for publication and for NIH grant money.

He noted that in the 1960s, about two out of three NIH grant requests were funded; today, the success rate for applicants for research funding is about one in five. At the same time, getting work published in the most esteemed journals, such as Nature, has become a “fetish” for some scientists, Fang said.

In one sense, the rise in retractions may mean that the scientific enterprise is working — bad work is being discovered and tossed out. But many observers note that universities and journals, while sometimes agreeable to admitting small mistakes, are at times loath to reveal that the essence of published work was simply wrong.

“The reader of scientific information is at the mercy of the scientific institution to investigate or not,” said Adam Marcus, who with Ivan Oransky founded the blog Retraction Watch in 2010. In this case, Marcus said, “if Hopkins doesn’t want to move, we may not find out what is happening for two or three years.”

The trouble is that a delayed response — or none at all — leaves other scientists to build upon shaky work. Fang said he has talked to researchers who have lost months by relying on results that proved impossible to reproduce.

Moreover, as Marcus and Oransky have noted, much of the research is funded by taxpayers. Yet when retractions are done, they are done quietly and “live in obscurity,” meaning taxpayers are unlikely to find out that their money may have been wasted.

Johns Hopkins University typically receives more than $600 million a year from NIH, according to NIH figures.

For someone who has taken on a battle with Johns Hopkins and Nature, Yuan is strikingly soft-spoken.

He grew up in Gainesville, Fla., and attended MIT and then medical school at Johns Hopkins. He worked briefly as a pediatrician and an assistant professor of pediatrics before deciding that he preferred pure research. He has a wife and two kids and is an accomplished violinist.

In 2001, he joined the lab of Jef Boeke, a Hopkins professor of molecular biology and genetics. Boeke’s work on the yeast genome is, as academics put it, “highly cited” — that is, other papers have used some of his articles numerous times for support. Last year, he was named a member of the prestigious American Academy of Arts and Sci­ences.

The lab’s research focused on developing a methodology for finding evidence of genes interacting, primarily in the yeast genome and then in the human genome. Genetic interactions are prized because they yield insights into the traits of the genes involved.

During Yuan’s time there, the lab received millions in NIH funding, and according to internal e-mails, the people in the lab were under pressure to show results. Yuan felt the pressure, too, he says, but as the point person for analyzing the statistical data emerging from the experiments, he felt compelled to raise his concerns.

As far back as 2007, as the group was developing the methodology that would eventually form the basis of the Nature paper, Yuan wrote an anguished e-mail to another senior member of the lab, Pamela Meluh.

“I continue to be in a state of chronic alarm,” he wrote in August 2007. “The denial that I am hearing from almost everyone in the group as a consensus is troubling to me.”

Meluh quickly wrote back: “I have the same level of concern as you in terms of data quality, but I have less basis to think it can be better. . . . I’m always torn between addressing your and my own concerns and being ‘productive.’ ”

Then Boeke weighed in, telling Yuan that if he could improve the data analysis, he should, but that “the clock is ticking.”

“NIH has already given us way more time than we thought we needed and at some point we’ve got to suck it up and run with what we have,” Boeke wrote to Meluh and Yuan.

A few years later, another deadline was looming, and Elise Feingold, an NIH administrator, wanted to know what the lab had accomplished.

“I do need some kind of progress report on what you have been doing the past two years . . . and what you think you can accomplish with these funds,” she wrote to Boeke.

Citing Feingold’s message, ­Meluh wrote to Yuan, asking for help in explaining what the lab had produced. Its members had worked diligently, Yuan says, but hadn’t arrived at the kind of significant findings that generally produce scientific papers.

“I want to make it look like we’ve been busy despite lack of publications,” Meluh wrote.

Meluh did not respond to a request for an interview. Boeke referred questions to the university’s public relations team, which declined to comment further. An NIH official declined to comment.

While Yuan was growing increasingly skeptical of the lab’s methodology, Yu-yi Lin, who was also working at the lab, was trying to extend it. In the past, it had been applied to the yeast genome; Lin would extend it to the human genome — and this would become the basis of the Nature paper.

Lin, who was from Taiwan, was an up-and-comer. As a graduate student at Johns Hopkins just a few years before, he’d won an award for his work in cell metabolism and aging. He was also arranging for a prestigious spot at National Taiwan University.

At one point, when he was still at the Boeke lab at Hopkins, Lin asked Yuan to help analyze the data that would become the basis for the Nature paper, Yuan says. Yuan said he declined to get involved because he thought the methodology still had deep flaws.

Interactions between Lin and Yuan at the lab were few, Yuan said, and at any rate, Yuan had other things to worry about. He was slowly being forced out. He was demoted in 2011 from research associate to an entry-level position. A disagreement over whether Yuan should have asked Boeke if he wanted a byline on a paper erupted into further trouble, e-mail and other records show.

The Johns Hopkins spokeswoman, Hoppe, declined to discuss Yuan’s job termination.

On Dec. 15, 2011, Yuan was forced to leave the lab. He wasn’t allowed to make copies of his cell collection. He spent the next month trying to keep his mind busy. He read books about JavaScript and Photoshop, which he thought would enrich his research abilities. As he looked for other research jobs, he sensed that he had been blackballed.

Then, in February 2012, the Nature paper was published.

The research was a “profound achievement” that would “definitely be a great help to solve and to treat many severe diseases,” according to a news release from National Taiwan University, where Lin was now working.

Upon reading it, Yuan said, he was astonished that Lin had used what he considered a flawed method for finding genetic interactions. It had proved troublesome in the yeast genome, he thought. Could it have possibly been more reliable as it was extended to the human genome?

Lin, Boeke and their co-authors reported discovering 878 genetic interactions, or “hits.”

But Yuan, who was familiar with the data and the statistics, reanalyzed the data in the paper and concluded that there was essentially no evidence for any more than a handful of the 878 genetic interactions.

One of the key problems, Yuan wrote to the Nature editors, was that the numerical threshold the investigators used for determining when a hit had arisen was too low. This meant they would report far more hits than there actually were.

Yuan also calculated that, given the wide variability in the data and the relative precision required to find a true hit, it would have been impossible to arrive at any conclusions at all. By analogy, it would be like a pollster declaring a winner in an election when the margin of error was larger than the difference in the polling results.

“The overwhelming noise in the . . . data and the overstated strength of the genetic interactions together make it difficult to reconstruct any scientific process by which the authors could have inferred valid results from these data,” Yuan wrote to the editors of Nature in July.

His analysis attacks only the first portion of the paper; even if he is correct, the second part of the paper could be true.

Nevertheless, Yuan wanted Nature to publish his criticism, and following instructions from the journal, he forwarded his letter to Boeke and Lin, giving them two weeks to respond.

Just as the two weeks were to elapse, Boeke wrote to Nature asking for an extension of time — “a couple weeks or more” — to address Yuan’s criticism. Boeke explained that end-of-summer schedules and the multiple co-authors made it difficult to respond on time.

A day later, Lin was discovered dead in his office at National Taiwan University.

“Renowned scientist found dead, next to drug bottles,” the headline in the Taipei Times said.

Even in his death, the Nature paper was a kind of shorthand for Lin’s scientific success.

“A research team [Lin] led was featured in the scientific journal Nature in February for their discovery of the key mechanism for maintaining cell energy balance — believed to be linked to cellular aging and cancer,” the newspaper said.

If there was a suicide note, it has not been made public, and it is difficult to know what went through Lin’s mind at the end of his life. The apparent suicide and the e-mail to Yuan suggest only that Lin may have been distraught over the dispute; they do not prove that he acted improperly.

Shortly after the Nature paper appeared, Yuan hired lawyer Lynne Bernabei to challenge the way he was terminated at Hopkins.

In late August, Yuan asked the Nature editors again whether they would publish his criticism. Lin was dead, but Boeke and the others had had a month to respond, and Yuan hadn’t heard a thing.

On Sept. 28, a Nature editor informed Yuan by e-mail that the journal was still waiting on a fuller response from Boeke and that “experiments are being done and probably a Correction written.”

Such a correction has not appeared.

So as a last attempt, he figured he’d try the federal government, which paid for much of the research. But the government suggested that the threat to the federal research, if there was any, ended with Lin’s death.

“It is our understanding that these allegations are being investigated by Johns Hopkins University,” said the letter from the Office of Research Integrity.

Besides, it noted, the person responsible for the paper was Lin.

“Deceased respondents no longer pose a risk,” the letter said.

http://www.washingtonpost.com/business/economy/doubts-about-johns-hopkins-research-have-gone-unanswered-scientist-says/2013/03/11/52822cba-7c84-11e2-82e8-61a46c2cde3d_story_4.html

Thanks to Kebmodee for bringing this to the attention of the It’s Interesting community.

Never Scrape Again: Windshield Coating Repels Frost

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A fogged-up camera lens can ruin a perfect shot, and a frosty car window can lead to potentially deadly accidents. To help keep glass clear in harsh weather, scientists are developing an advanced new coating that resists both fogging and frosting.

Glass fogs up and frosts because of water. So you might assume so-called hydrophobic materials, which repel water, provide the best method of fighting such moisture. However, these solutions tend only to make water bead up, scattering light and obscuring views.

Researchers have also experimented with the opposite tactic, attempting to prevent fogging and frosting using hydrophilic materials, which attract water. Here, researchers hope to smear water across the glass surfaces in uniform sheets, to keep the moisture from distorting light. Although these materials work against fog, they can’t prevent frosting. When cold glass encounters humid air, the layer of water that develops simply freezes.

However, the new coating possesses both water-repelling and water-attracting properties, so it works against both fog and frost. The material contains organic compounds with both hydrophilic and hydrophobic components. The hydrophilic ingredients love water so much they absorb moisture, trapping it and keeping it from easily forming ice crystals. This lowers water’s usual freezing temperature and dramatically reduces frosting.

Meanwhile, the material’s hydrophobic components help repel contaminants that might spoil the hydrophilic effect.

“We have no freezing of water, even at low temperatures. It remains completely clear,” researcher Michael Rubner, a materials scientist at MIT, told TechNewsDaily.

When the new coating warms up from the freezing cold, it releases the water, “which just evaporates,” Rubner added.

The new coating does have its limits. “If it’s overwhelmed with water, any excess water can freeze,” Rubner said. “You wouldn’t want this on an airplane wing that constantly gets water on it, but an application like eyeglasses or windshields, it can be amazing.”

The researchers are now seeking to enhance the material’s durability to mechanical stresses. They detailed their findings online Jan. 29 in the journal ACS Nano.

http://www.livescience.com/27611-never-scrape-again-windshield-coating-repels-frost.html

14th-century plague skeletons unearthed at London station

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If you find yourself walking in central London, think about this: not far beneath your feet there may well be human remains. On the edge of Charterhouse Square in the district of Farringdon, engineers were digging an access tunnel for the new Crossrail underground railway when they uncovered 12 skeletons.

“We suspected there might be bodies there,” says Crossrail’s chief archaeologist, Jay Carver. “When the excavation machine uncovered the first bones, we went in and excavated by hand.”

Historical documents suggest the then-lord mayor of London ordered an emergency burial ground to be prepared in Farringdon, in response to the Black Death sweeping Europe in the 14th century.

Relatively few people died in the early stages of the plague and so they were buried in an orderly, east-west orientation. In later years there were more dead, and in their graves bodies are essentially heaped on top of one another. The newly discovered Farringdon bodies, just 2.5 metres below the surface, are neatly oriented and were probably wrapped in shrouds and interred: the Crossrail team have found shroud pins but no fabric remains and no sign of coffins. Pottery found at the same depth as the bodies has been dated to before 1350.

The skeletons will now be removed to the Museum of London Archaeology, where radiocarbon dating will determine the approximate age of the bodies. Skeletons discovered in a plague pit in nearby Smithfield yielded DNA markers identifying the plague bacterium Yersinia pestis.

“Our evidence suggests these are burials associated with that period and therefore that these are people buried during the emergency black death period,” says Carver. “If we can find a signature of that bacterium it will provide some interesting new data about this important historical event.”

The Crossrail team have a licence from the Ministry of Justice allowing them to exhume the remains, and at some point the archaeologists will make a decision about curation. Will the skeletons be reburied?

“They may be placed in a charnel store in a crypt, in case future generations want to study them,” says Carver. “It’s an academic and legal decision.”

http://www.newscientist.com/blogs/shortsharpscience/2013/03/crossrail-plague-skeleton.html?cmpid=RSS|NSNS|2012-GLOBAL|online-news

Facebook Preferences Predict Personality Traits

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Research shows a strong association between liking “curly fries” on Facebook and having high IQ.

Every day, millions of people click on Facebook “Like” buttons, boldly declaring their preferences for a variety of things, such as books, movies, and cat videos. But those “likes” may reveal more than they intend, such as sexual orientation, drug use, and religious affiliation, according to a study that analyzed the online behavior of thousands of volunteers.

Your preferences define you. Researchers have known for decades that people’s personal attributes—gender, age, religion, sexual orientation, and personality type—correlate with their choice of products, concepts, and activities. Just consider the different populations at an opera and a NASCAR race. This is why companies are so eager to gather personal information about their consumers: Advertising is far more effective when it is targeted to groups of people who are more likely to be interested in a product. The only aspect that has changed is the increasing proportion of personal information that is available as digital data on the Internet. And Facebook has become a major hub for such data through its like button. A team led by Michal Kosinski, a psychologist at the University of Cambridge in the United Kingdom as well as at Microsoft Research, wondered just how much people’s likes reveal about them.

The Likes data are public information. The hard part was getting the data on intelligence and other such attributes to compare with the likes. For that, Kosinski and his Cambridge colleague David Stillwell created a Facebook app called myPersonality. After agreeing to volunteer as a research subject, users of the myPersonality app answer survey questions and take a series of psychological tests that measure things such as intelligence, competitiveness, extraversion versus introversion, and general satisfaction with life. Kosinski and Stillwell not only get those data but also data from the user’s Facebook profile and friends network. In return, users get a peek at their own information. More than 4 million people have volunteered already.

The researchers used data from 58,000 U.S.-based myPersonality volunteers to build a statistical model. Then, they used a sample of myPersonality volunteers to test how well the model could predict personal attributes from likes.

Facebook likes are an amazingly good predictor of personal attributes, the team reports online today in the Proceedings of the National Academy of Sciences. The most accurate predictions were for gender (93%) and race (95%), as limited to Caucasian versus African American. But people’s likes also predicted far more sensitive personal attributes such as homosexuality (88% for men, 75% for women), religion (82%), political party membership (85%), and even use of cigarettes, alcohol, and drugs (73%, 70%, and 65%, respectively). Many of the likes that had the strongest prediction power make intuitive sense, such as “Jesus” for Christians and “Glee” for gay men. But others were harder to explain, such as the strong association between liking “curly fries” and having high IQ.

“What was traditionally laboriously assessed on an individual basis can be automatically inferred for millions of people without them even noticing,” Kosinski says, “which is both amazing and a bit scary.”

Science NOW contacted Facebook’s in-house social scientists about the work. The study’s results are “hardly surprising,” the company contends in their official response. “On Facebook, people can share the things they like—like bands, brands, sports teams, public figures, etc. By using Login with Facebook on third party sites, people can take their Likes and interests with them around the web—to have more personalized experiences.”

“I am glad that Facebook is aware that likes allow predicting individual traits,” Kosinski says. “I am afraid, however, that users [of Facebook and other online environments] do not realize that by ‘carrying around’ their likes, songs they listen to, Web sites they visit, and other kinds of online behavior, they are exposed to a degree potentially well beyond what they expect or would find comfortable.”

Whether people are comfortable, advertisers are sure to start paying attention to what they like, now that a Rosetta stone exists for translating it into personal data.

http://news.sciencemag.org/sciencenow/2013/03/facebook-preferences-predict-per.html

Mars Rover Finds “All the Prerequisites For Life — a Habitable Environment”

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Curiosity has found discovered that Mars possesses conditions that could have supported ancient — and future — life, announced NASA scientists during a press conference today.

“A fundamental question for this mission is whether Mars could have supported a habitable environment,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program. “From what we know now, the answer is yes.”

Reportedly, the sample taken from the sedimentary rock targeted by Curiosity contains sulfur, nitrogen, hydrogen, oxygen, phosphorus, and carbon, all key ingredients for life. One NASA scientist referred to the findings as “really something special,” as well as containing up to 20% clay — which is formed by the reaction of relatively fresh water with igneous materials.

Additonally, scientists discovered a mixture of oxidized, less-oxidized, and even non-oxidized chemicals capable of supporting an energy gradient of the sort many microbes on Earth require for survival.

“The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulfates and sulfides that indicate a possible chemical energy source for micro-organisms,” said Paul Mahaffy, a NASA official.

http://www.policymic.com/mobile/articles/29536/mars-rover-finds-all-the-prerequisites-for-life-a-habitable-environment

Astrobiologists Find Ancient Fossils in Fireball Fragments

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On 29 December 2012, a fireball lit up the early evening skies over the Sri Lankan province of Polonnaruwa. Hot, sparkling fragments of the fireball rained down across the countryside and witnesses reported the strong odour of tar or asphalt.

Over the next few days, the local police gathered numerous examples of these stones and sent them to the Sri Lankan Medical Research Institute of the Ministry of Health in Colombo. After noticing curious features inside these stones, officials forwarded the samples to a team of astrobiologists at Cardiff University in the UK for further analysis.

The results of these tests, which the Cardiff team reveal today, are extraordinary. They say the stones contain fossilised biological structures fused into the rock matrix and that their tests clearly rule out the possibility of terrestrial contamination.

In total, Jamie Wallis at Cardiff University and a few buddies received 628 stone fragments collected from rice fields in the region. However, they were able to clearly identify only three as possible meteorites.

The general properties of these three stones immediately mark them out as unusual. One stone, for example, had a density of less than 1 gram per cubic centimetre, less than all known carbonaceous meteorites. It had a partially fused crust, good evidence of atmospheric heating, a carbon content of up to 4 per cent and contained an abundance of organic compounds with a high molecular weight, which is not unknown in meteorites. On this evidence, Wallis and co think the fireball was probably a small comet.

The most startling claims, however, are based on electron microscope images of structures within the stones (see above). Wallis and co say that one image shows a complex, thick-walled, carbon-rich microfossil about 100 micrometres across that bares similarities with a group of largely extinct marine dinoflagellate algae.

They say another image shows well-preserved flagella that are 2 micrometres in diameter and 100 micrometres long. By terrestrial standards, that’s extremely long and thin, which Wallis and co interpret as evidence of formation in a low-gravity, low-pressure environment.

Wallis and co also measured the abundance of various elements in the samples to determine their origin. They say that low levels of nitrogen in particular rule out the possibility of contamination by modern organisms which would have a much higher nitrogen content. The fact that these samples are also buried within the rock matrix is further evidence, they say.

Wallis and co are convinced that the lines of evidence they have gathered are powerful and persuasive. “This provides clear and convincing evidence that these obviously ancient remains of extinct marine algae found embedded in the Polonnaruwa meteorite are indigenous to the stones and not the result of post-arrival microbial contaminants,” they conclude.

There’s no question that a claim of this kind is likely to generate controversy. Critics have already pointed out that the stones could have been formed by lightning strikes on Earth although Wallis and co counter by saying there was no evidence of lightning at the time of the fireball and that in any case, the stones do not bear the usual characteristics of this kind of strike. What’s more, the temperatures generated by lightning would have destroyed any biological content.

Nevertheless, extraordinary claims require extraordinary evidence and Wallis and co will need to make their samples and evidence available to the scientific community for further study before the claims will be taken seriously.

If the paper is taken at face value, one obvious question that arises is where these samples came from. Wallis and co have their own ideas: “The presence of fossilized biological structures provides compelling evidence in support of the theory of cometary panspermia first proposed over thirty years ago,” they say.

This is an idea put forward by Fred Hoyle and Chandra Wickramasinghe, the latter being a member of the team who has carried out this analysis.

There are other explanations, of course. One is that the fireball was of terrestrial origin, a remnant of one of the many asteroid impacts in Earth’s history that that have ejected billions of tonnes of rock and water into space, presumably with biological material inside. Another is that the structures are not biological and have a different explanation.

Either way, considerably more work will have to be done before the claims from this team can be broadly accepted. Exciting times ahead!

http://www.technologyreview.com/view/512381/astrobiologists-find-ancient-fossils-in-fireball-fragments/

Thanks to Kebmodee for bringing this to the attention of the It’s Interesting community.

Flip of a single molecular switch makes an old brain young

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The flip of a single molecular switch helps create the mature neuronal connections that allow the brain to bridge the gap between adolescent impressionability and adult stability. Now Yale School of Medicine researchers have reversed the process, recreating a youthful brain that facilitated both learning and healing in the adult mouse.

Scientists have long known that the young and old brains are very different. Adolescent brains are more malleable or plastic, which allows them to learn languages more quickly than adults and speeds recovery from brain injuries. The comparative rigidity of the adult brain results in part from the function of a single gene that slows the rapid change in synaptic connections between neurons.

By monitoring the synapses in living mice over weeks and months, Yale researchers have identified the key genetic switch for brain maturation a study released March 6 in the journal Neuron. The Nogo Receptor 1 gene is required to suppress high levels of plasticity in the adolescent brain and create the relatively quiescent levels of plasticity in adulthood. In mice without this gene, juvenile levels of brain plasticity persist throughout adulthood. When researchers blocked the function of this gene in old mice, they reset the old brain to adolescent levels of plasticity.

“These are the molecules the brain needs for the transition from adolescence to adulthood,” said Dr. Stephen Strittmatter. Vincent Coates Professor of Neurology, Professor of Neurobiology and senior author of the paper. “It suggests we can turn back the clock in the adult brain and recover from trauma the way kids recover.”

Rehabilitation after brain injuries like strokes requires that patients re-learn tasks such as moving a hand. Researchers found that adult mice lacking Nogo Receptor recovered from injury as quickly as adolescent mice and mastered new, complex motor tasks more quickly than adults with the receptor.

“This raises the potential that manipulating Nogo Receptor in humans might accelerate and magnify rehabilitation after brain injuries like strokes,” said Feras Akbik, Yale doctoral student who is first author of the study.

Researchers also showed that Nogo Receptor slows loss of memories. Mice without Nogo receptor lost stressful memories more quickly, suggesting that manipulating the receptor could help treat post-traumatic stress disorder.

“We know a lot about the early development of the brain,” Strittmatter said, “But we know amazingly little about what happens in the brain during late adolescence.”

Other Yale authors are: Sarah M. Bhagat, Pujan R. Patel and William B.J. Cafferty

The study was funded by the National Institutes of Health. Strittmatter is scientific founder of Axerion Therapeutics, which is investigating applications of Nogo research to repair spinal cord damage.

http://news.yale.edu/2013/03/06/flip-single-molecular-switch-makes-old-brain-young

Supermassive black hole spins at nearly the speed of light

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This artist’s concept illustrates a supermassive black hole with millions to billions times the mass of our sun. It’s surrounded by matter flowing onto the black hole in what is termed an accretion disk. Also shown is an outflowing jet of energetic particles, believed to be powered by the black hole’s spin. High energy X-radiation lights up the disk, which reflects it, making the disk a source of X-rays. The reflected light enables astronomers to see how fast matter is swirling in the inner region of the disk, and ultimately to measure the black hole’s spin rate.

Nothing can escape a black hole, even light, because to wrench away from its titanic gravitational pull, you’d have to move faster than light is capable of traveling. And nothing can do that, as far as anyone knows. As matter falls into a black hole’s gaping maw, it superheats to millions of degrees, screaming a final cry of X-rays as it is torn apart. At a specific point called an event horizon, the matter disappears and is never heard from again.

A pair of X-ray telescopes recently watched some of these X-ray death gasps and were able to figure out how fast a black hole is spinning. This is “hugely important” for black hole science, according to researchers working with NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR space telescope. One particularly cool finding: The black hole is spinning almost as fast as Einstein’s theory of gravity says it possibly could. It’s spinning at almost the speed of light.

The galaxy in question is called NGC 1365, which is about twice the size of the Milky Way and located about 60 million light years away. The black hole is about 2 million times more massive than the sun. Scientists using NuSTAR and the European Space Agency’s XMM-Newton satellite wanted to measure how fast it is spinning. This is a key feature of black holes that is related to their size and the way they gobble up stars, gas and even other black holes.

The problem is that black holes are hard to study, because, you know, not even light can escape them. To measure them, you have to measure their effect on their surroundings–like the X-rays emitted by dying matter. This is hard to do because objects between us and them can get in the way, however, making the X-rays look distorted. There have been two competing models explaining why the X-rays look warped: Either gravitational distortion caused by black hole gravity, or distortion caused by intervening clouds of gas and dust.

In this new study, NuSTAR and XMM-Newton set out to determine which one is right. The telescopes carefully traced the X-rays emitted at the very, very edge of the black hole, right near the event horizon, or the point of no return. By combining their distinct viewing abilities, the two telescopes were able to see a wide range of X-ray energies, and figure out that the X-rays are not actually distorted by intervening gas clouds. They look distorted because the black hole is spinning, and its immense gravity warps spacetime as it swirls around. This information was used to tell just how fast the black hole is spinning: Just below the universal speed limit.

Along with new information about this particular black hole, this study suggests that black hole observations can remove a little bit of ambiguity. This will help astronomers continue to unravel the mysteries of these galactic monsters. A paper describing the findings is published last week in Nature.

http://www.popsci.com/science/article/2013-02/new-telescope-discovery-distant-gargantuan-black-hole-spins-near-light-speed