Looking for life by the light of dying stars

Apr. 24, 2013 ? Because it has no source of energy, a dead star -- known as a white dwarf -- will eventually cool down and fade away. But circumstantial evidence suggests that white dwarfs can still support habitable planets, says Prof. Dan Maoz of Tel Aviv University's School of Physics and Astronomy.

Now Prof. Maoz and Prof. Avi Loeb, Director of Harvard University's Institute for Theory and Computation and a Sackler Professor by Special Appointment at TAU, have shown that, using advanced technology to become available within the next decade, it should be possible to detect biomarkers surrounding these planets -- including oxygen and methane -- that indicate the presence of life.

Published in the Monthly Notices of the Royal Astronomical Society, the researchers' "simulated spectrum" demonstrates that the James Webb Space Telescope (JWST), set to be launched by NASA in 2018, will be capable of detecting oxygen and water in the atmosphere of an Earth-like planet orbiting a white dwarf after only a few hours of observation time -- much more easily than for an Earth-like planet orbiting a sun-like star.

Their collaboration is made possible by the Harvard TAU Astronomy Initiative, recently endowed by Dr. Raymond and Beverly Sackler.

Faint light, clear signals

"In the quest for extraterrestrial biological signatures, the first stars we study should be white dwarfs," said Prof. Loeb. Prof. Maoz agrees, noting that if "all the conditions are right, we'll be able to detect signs of life" on planets orbiting white dwarf stars using the much-anticipated JWST.

An abundance of heavy elements already observed on the surface of white dwarfs suggest rocky planets orbit a significant fraction of them. The researchers estimate that a survey of 500 of the closest white dwarfs could spot one or more habitable planets.

The unique characteristics of white dwarfs could make these planets easier to spot than planets orbiting normal stars, the researchers have shown. Their atmospheres can be detected and analyzed when a star dims as an orbiting planet crosses in front of it. As the background starlight shines through the planet's atmosphere, elements in the atmosphere will absorb some of the starlight, leaving chemical clues of their presence -- clues that can then be detected from the JWST.

When an Earth-like planet orbits a normal star, "the difficulty lies in the extreme faintness of the signal, which is hidden in the glare of the 'parent' star," Prof. Maoz says. "The novelty of our idea is that, if the parent star is a white dwarf, whose size is comparable to that of an Earth-sized planet, that glare is greatly reduced, and we can now realistically contemplate seeing the oxygen biomarker."

In order to estimate the kind of data that the JWST will be able to see, the researchers created a "synthetic spectrum," which replicates that of an inhabited planet similar to Earth orbiting a white dwarf. They demonstrated that the telescope should be able to pick up signs of oxygen and water, if they exist on the planet.

A critical sign of life

The presence of oxygen biomarkers would be the most critical signal of the presence of life on extraterrestrial planets. Earth's atmosphere, for example, is 21 percent oxygen, and this is entirely produced by our planet's plant life as a result of photosynthesis. Without the existence of plants, an atmosphere would be entirely devoid of oxygen.

The JWST will be ideal for hunting out signs of life on extraterrestrial planets because it is designed to look into the infrared region of the light spectrum, where such biomarkers are prominent. In addition, as a space-based telescope, it will be able to analyze the atmospheres of Earth-like planets outside our solar system without weeding out the similar signatures of Earth's own atmosphere.

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/space_time/nasa/~3/ftCCORIXq54/130424112318.htm

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A.J. Clemente Appears on Letterman, Pushes for ESPN Job

Source: http://www.thehollywoodgossip.com/2013/04/aj-clemente-appears-on-letterman-pushes-for-espn-job/

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Coyotes Kill Pet Dogs in Frontenac ? CBS St. Louis

FRONTENAC, MO. (KMOX) - One Frontenac family says coyotes are to blame for the death of their two small dogs over the weekend.

Debbie Rudawsky says her sons let the two dogs out at about 10:15 at night, and when the dogs didn?t come back in after 20 minutes, the family became worried.

When the family decided to drive the neighborhood, looking for the dogs, they saw them in the yard, both had been attacked.

Debbie says the vet did an autopsy and concluded that each dog was attacked by a coyote.

?She felt very confident that it was at least two animals. The injuries were around the neck and the bruising was such that their necks were snapped.? said Rudawsky.

The Frontenac city administrator is sending a notice around to all resident to be on the watch for coyotes.

Do coyotes often roam the burbs?

Wildlife Biologist with the Missouri Department of Conservation, Tom Meister says coyotes are adaptable and have no natural predator so they can survive very well in the suburbs.

?They will eat just about anything? said Meister ?garbage, pet food, apples, so there is quite a smorgasbord for them in urban areas.?\

Coyotes have, and will, invade neighborhoods, and right now they?ve likely had young and are out looking for food. ?What can you do? says Meister, ?harass them.? ?squirt them with a hose scare them by banging pots and pans.?

He also suggests keeping food out of sight and says make noise before you leave the house and don?t let your pets outside unattended.

Source: http://stlouis.cbslocal.com/2013/04/23/coyotes-kill-pet-dogs-in-frontenac/

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Huawei outlines plan to regain its share of European smartphone market

Last year, Huawei's Device Business Group set an ambitious goal of shipping 60 million smartphones, but managed only 32 million, keeping it out of IDC's top five smartphone vendors in 2012. That said, for Q4 that same year Huawei did finally break into top three, but it didn't change the fact that it had been a tough period for Huawei's smartphone division, especially for its CMO Shao Yang (pictured above with his 6.1-inch Ascend Mate). At the 2013 Huawei Global Analyst Summit in Shenzhen yesterday, the exec was kind enough to share his side of the story about the hurdles his team faced last year -- the period when Huawei was transforming from an original design manufacturer (ODM) to serve others, to an original equipment manufacturer (OEM) in order to build devices according to its own specifications.

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/kBR-4bK1Pwc/

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Gut Bacteria Implicated In Heart Attacks, Stroke - Huffington Post

By Sharon Begley
NEW YORK, April 24 (Reuters) - Thousands of heart attack victims every year have none of the notorious risk factors before their crisis - not high cholesterol, not unhealthy triglycerides. Now the search for the mystery culprits has turned up some surprising suspects: the trillions of bacteria and other microbes living in the human gut.
In a study released on Wednesday, scientists discovered that some of the bugs turn lecithin - a nutrient in egg yolks, liver, beef, pork and wheat germ - into an artery-clogging compound called TMAO. They also found that blood levels of TMAO predict heart attack, stroke or death, and do so "independent of other risk factors," said Dr Stanley Hazen, chairman of cellular and molecular medicine at the Cleveland Clinic's Lerner Research Institute, who led the study.
That suggests a TMAO test could enter the arsenal of blood tests that signal possible cardiovascular problems ahead. "TMAO might identify people who are at risk (for heart attacks and strokes) despite having no other risk factors," Hazen said.
The discovery also suggests a new approach to preventing these cardiovascular events: altering gut bacteria so they churn out less TMAO.
The study joins a growing list of findings that link human "microbiota" - microbes in the gut, nose and genital tract, and on the skin - to health and disease. Research has shown that certain species of gut bacteria protect against asthma, for instance, while others affect the risk of obesity. Last week scientists reported that circumcision alters bacteria in the penis, and that this change (not only the anatomical one) helps protect men from HIV/AIDS, probably by reducing the number of bacteria that live in oxygen-free environments such as under the foreskin.
"It's very strong work," Dr Martin Blaser of New York University Langone Medical Center, a pioneer in studies of the microbiota, said of the TMAO study. "They show clearly that human microbiota play a key role in producing TMAO, suggesting new approaches to prevention and treatment" of cardiovascular disease.

NORMAL CHOLESTEROL, FATAL HEART ATTACK
The new study builds on a 2011 discovery by the Cleveland Clinic team that, in lab mice, gut bacteria turn lecithin in food into TMAO, or trimethylamine-N-oxide, causing heart disease. In addition, they found, people with high levels of TMAO are more likely to have heart disease.
But that research left two questions hanging: Do human gut bacteria trigger the lecithin-to-TMAO alchemy, like those in mice? And do high levels of TMAO predict heart attacks and stroke in people many years out, not simply mark the presence of cardiovascular disease at the time of the blood test?
To answer the first question, Hazen and his colleagues had 40 healthy adults eat two hard-boiled eggs, which contain lots of lecithin. Just as in lab mice, TMAO levels in the blood rose. After a week of broad-spectrum antibiotics, however, the volunteers' TMAO levels barely budged after they ate eggs, the researchers reported in the New England Journal of Medicine.
"That showed that the intestinal bacteria (which antibiotics kill) are essential for forming TMAO," said Hazen.
Next, to see whether TMAO predicts cardiovascular events, the researchers measured its levels in 4,007 heart patients. After accounting for such risk factors as age and a past heart attack, they found that high levels of TMAO were predictive of heart attack, stroke and death over the three years that the patients were followed.
Moreover, TMAO predicted risk more accurately than triglyceride or cholesterol levels, Hazen said. And it did so in people without substantial coronary artery disease or dangerous lipid levels as well as in sicker patients.
Specifically, people in the top 25 percent of TMAO levels had 2.5 times the risk of a heart attack or stroke compared to people in the bottom quartile.
The reason TMAO is so potent is that it makes blood cholesterol build up on artery walls, causing atherosclerosis (hardening of the arteries) and, if the buildup ruptures and blocks an artery, stroke or heart attack.
Earlier this month, the Cleveland Clinic researchers reported that gut bugs also transform carnitine, a nutrient found in red meat and dairy products, into TMAO, at least in meat eaters. Vegetarians made much less TMAO even when eating carnitine as part of the study, suggesting that avoiding meat reduces the gut bacteria that turn carnitine into TMAO, while regular helpings of dead animals encourages their growth and thus the production of TMAO.
More studies are needed to show whether TMAO reliably predicts cardiovascular crises, and does so better than other blood tests. Experts disagree on how many people have no other risk factors but would be flagged by TMAO. Dr Gordon Tomaselli, chief of cardiology at Johns Hopkins University School of Medicine and past president of the American Heart Association, guesses it is less than 10 percent or so of the people who eventually have heart crises.
Someone with high levels of TMAO could reduce her cardiovascular risk by eating fewer egg yolks and less beef and pork. But someone with a two-eggs-a-day habit but low TMAO probably has gut microbes that aren't very adept at converting lecithin to TMAO, meaning she can eat eggs and the like without risking a coronary.
Just as statins control unhealthy cholesterol, prebiotics (compounds that nurture "healthy" gut microbes) or probiotics (the good bugs themselves) might control unhealthy TMAO. For now, however, no one knows which prebiotics or probiotics might do that. In one study, probiotics actually increased TMAO-producing bacteria - "not what you want," Hazen said.
Neither will popping antibiotics work: bacteria become resistant to the drugs. Developing compounds that crimp the ability of the bacteria to turn lecithin into TMAO, Hazen said, is more likely to succeed. (Reporting by Sharon Begley; editing by Michelle Gershberg and Prudence Crowther)

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Source: http://www.huffingtonpost.com/2013/04/24/gut-bacteria-heart-attack-stroke-tmao-lecithin_n_3149663.html

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As Bush library opening puts his presidency back in the spotlight, his approval rating is up (Washington Post)

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Logitech G500s Laser Gaming Mouse Impressions - MTV Multiplayer

Over the last several months I've gotten back into PC gaming, and as such, I've been on the market for some peripherals to replace my aging gear. Fortunately, the good people over at Logitech have provided several new PC periphs for all your gaming needs. Having whipped up hundreds of computer accessories, ranging from keyboards?to mice to speakers, since the 8o's Logitech is no stranger to the gaming scene and odds are that you've come across one of their devices at some point. Logitech's G Series, the latest batch of higher-end gaming peripherals, touch on their "Science wins" branding focusing on unique materials and mathematically precise functionality in hopes of improving your game. Enter the G500s Laser Gaming Mouse, probably the last gaming mouse you'll ever need.

I've spent a little over a week with the G500s and I've gotta say thay I'm pretty impressed. The G500s is feature heavy with many practical bells and whistles for total control of your gaming habits. A quick look at the perks include ultra-slick pads for effortless gliding, a bottom-loaded cartiridge for adding weight, buttons for on-the-fly adjustable DPI sensitivity, dual-mode scroll wheel, and special hydrophodic coating for sweaty hands there's not much else you would need. Additionally, all the buttons can be reconfigured for personallized commands. It's a neat package that stands above many other mice of the same price range.

I've taken a real liking to the feel of the G500s as it comfortably fits my hands. Often, mice tend to be a little short on surface area, but Logitech provides just the right amount of bulk to allow you to rest your hand without cramping. There's also a slight resting spot for your thumb, too, that helps alleviate any stress for those extended sessions. All around, it's a mouse that feels like an extension of your hand rather than a awkward device that's oo small.

The other feature more discerning users will enjoy is the adjustable weights. I tend to lean towards maximum heft as I play with slightly heavy handed and found that weightier mice just feel "right." The G500s can add up to 27 grams to provide making the traditional feather light mouse into a dense lardy biscuit of a peripheral. If you lean the other way, then the G500s still feels solid without having that "too-light-so-it-must-be-cheap" feeling. Adding/removing weight is relatively painless -- with the press of a button a cartridge pops out and the small metal tabs into the holes and then pop back in. The cart stuck a few times but a simple shake dislodged it from its housing.

Real performance rest squarely on the lightning fast USB report rate and with 1000 reports a second you'll pretty much never experience a drop in the signal even during the most intense gaming events. You're also able to fine tune tracking at the touch of a button -- anywhere from 200 DPI to 8200 DPI. By the nature of its design, the G500s is probably best for shooters and RTSs, where responsiveness matters most. The buttons are quick to press without feeling too sensitive and all the secondary and tertiary buttons are within a comfortable reach. Coupled with the slick pads on the bottom and you'll have an A+ pro-level gaming mouse.

Related posts:
Nintendo Confirms New 'Pikmin 3' Character, August Release Date
Nintendo Reveals New 'The Legend of Zelda' Game For 3DS!

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Tags gaming mouse, Logitech G500s Laser Gaming Mouse, PC, peripher

Source: http://multiplayerblog.mtv.com/2013/04/23/logitech-g500s-laser-gaming-mouse-impressions/

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