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June 28, 2013

New system uses low-power Wi-Fi signal to track moving humans -- even behind walls

The comic-book hero Superman uses his X-ray vision to spot bad guys lurking behind walls and other objects. Now we could all have X-ray vision, thanks to researchers at MIT's Computer Science and Artificial Intelligence Laboratory.

Researchers have long attempted to build a device capable of seeing people through walls. However, previous efforts to develop such a system have involved the use of expensive and bulky radar technology that uses a part of the electromagnetic spectrum only available to the military.

Now a system being developed by Dina Katabi, a professor in MIT's Department of Electrical Engineering and Computer Science, and her graduate student Fadel Adib, could give all of us the ability to spot people in different rooms using low-cost Wi-Fi technology. "We wanted to create a device that is low-power, portable and simple enough for anyone to use, to give people the ability to see through walls and closed doors," Katabi says.

The system, called "Wi-Vi," is based on a concept similar to radar and sonar imaging. But in contrast to radar and sonar, it transmits a low-power Wi-Fi signal and uses its reflections to track moving humans. It can do so even if the humans are in closed rooms or hiding behind a wall.

June 27, 2013

Solar power heads in a new direction: Thinner

Most efforts at improving solar cells have focused on increasing the efficiency of their energy conversion, or on lowering the cost of manufacturing. But now MIT researchers are opening another avenue for improvement, aiming to produce the thinnest and most lightweight solar panels possible.

Such panels, which have the potential to surpass any substance other than reactor-grade uranium in terms of energy produced per pound of material, could be made from stacked sheets of one-molecule-thick materials such as graphene or molybdenum disulfide.

Pound for pound, he says, the new solar cells produce up to 1,000 times more power than conventional photovoltaics. At about one nanometer (billionth of a meter) in thickness, "It's 20 to 50 times thinner than the thinnest solar cell that can be made today," Grossman adds. "You couldn't make a solar cell any thinner."

June 25, 2013

Quantum interaction: 10,000 times faster than light

How fast do quantum interactions happen? Faster than light, 10,000 times faster.

That's what a team of physicists led by Juan Yin at the University of Science and Technology of China in Shanghai found in an experiment involving entangled photons, or photons that remain intimately connected, even when separated by vast distances.They wanted to see what would happen if you tried assigning a speed to what Einstein called "spooky action at a distance."

They didn't find anything unexpected, but that wasn't the point: in physics, sometimes it's good to be sure. The group published their work on the ArXiv.org, a preprint server for physics papers.

Breastfeeding boosts ability to climb social ladder

Breastfeeding not only boosts children's chances of climbing the social ladder, but it also reduces the chances of downwards mobility, suggests a large study published online in the Archives of Disease in Childhood.

The findings are based on changes in the social class of two groups of individuals born in 1958 (17,419 people) and in 1970 (16,771 people).

The researchers asked each of the children's mums, when their child was five or seven years old, whether they had breastfed him/her.

They then compared people's social class as children -- based on the social class of their father when they were 10 or 11 -- with their social class as adults, measured when they were 33 or 34.
Social class was categorised on a four-point scale ranging from unskilled/semi-skilled manual to professional/managerial.

June 21, 2013

Plants 'seen doing quantum physics'

The idea that plants make use of quantum physics to harvest light more efficiently has received a boost.

Plants gather packets of light called photons, shuttling them deep into their cells where their energy is converted with extraordinary efficiency.

A report in Science journal adds weight to the idea that an effect called a "coherence" helps determine the most efficient path for the photons.

Experts have called the work "a nice proof" of some contentious ideas.

Solitary mutation destroys key 'window' of brain development

Scientists from the Florida campus of The Scripps Research Institute (TSRI) have shown in animal models that brain damage caused by the loss of a single copy of a gene during very early childhood development can cause a lifetime of behavioral and intellectual problems.

The study, published this week in the Journal of Neuroscience, sheds new light on the early development of neural circuits in the cortex, the part of the brain responsible for functions such as sensory perception, planning and decision-making.

The research also pinpoints the mechanism responsible for the disruption of what are known as "windows of plasticity" that contribute to the refinement of the neural connections that broadly shape brain development and the maturing of perception, language, and cognitive abilities.

Study: 70 Percent Of Americans On Prescription Drugs

Researchers find that nearly 70 percent of Americans are on at least one prescription drug, and more than half receive at least two prescriptions.

Mayo Clinic researchers report that antibiotics, antidepressants and painkiller opioids are the most common prescriptions given to Americans. Twenty percent of U.S. patients were also found to be on five or more prescription medications.

The study is uncovering valuable information to the researchers about U.S. prescription practices.


“Often when people talk about health conditions they’re talking about chronic conditions such as heart disease or diabetes,” Dr. St. Sauver stated in a Mayo Clinic press release. “However, the second most common prescription was for antidepressants — that suggests mental health is a huge issue and is something we should focus on. And the third most common drugs were opioids, which is a bit concerning considering their addicting nature.”

New Electronics Can Withstand Bodily Fluids

Electronics and bodily fluids don't mix well. But new technology enables electronic devices to function in direct contact with tissues inside the body. The technology could allow scientists to make sensors that detect the early stages of organ transplant rejection, or create artificial nerves, researchers say.

Of course, many electronic devices already reside in the body — pacemakers, for example. But their electronics don't come in direct contact with bodily fluids because they are enclosed in hermetically sealed stainless steel and sprayed with chemicals that inhibit the body's immune response (which would otherwise reject them).

"What we're doing here is [developing] electronics working in concert with the body," study researcher Paul Berger, an electrical and computer engineer at Ohio State University in Columbus, told LiveScience. One of these is a protein sensor that "could be a sort of canary in a coal mine for transplant rejection," Berger said. [5 Crazy Technologies That Are Revolutionizing Biotech]

June 17, 2013

Scientists say new study shows pig health hurt by GMO feed

Pigs fed a diet of only genetically modified grain showed markedly higher stomach inflammation than pigs who dined on conventional feed, according to a new study by a team of Australian scientists and U.S. researchers.

The study adds to an intensifying public debate over the impact of genetically modified crops, which are widely used by U.S. and Latin American farmers and in many other countries around the world.

The study was published in the June issue of the peer-reviewed Journal of Organic Systems by researchers from Australia who worked with two veterinarians and a farmer in Iowa to study the U.S. pigs.

Obese male mice father offspring with higher levels of body fat

Male mice who were fed a high-fat diet and became obese were more likely to father offspring who also had higher levels of body fat, a new Ohio University study finds.

The effect was observed primarily in male offspring, despite their consumption of a low-fat diet, scientists reported today at the annual meeting of The Endocrine Society in San Francisco, Calif.

"We've identified a number of traits that may affect metabolism and behavior of offspring dependent on the pre-conception diet of the father," said Felicia Nowak, an associate professor of biomedical sciences in Ohio University's Heritage College of Osteopathic Medicine who is lead author on the study.

The researchers point to epigenetics -- the way genes are expressed, as opposed to mutations in DNA that are "hard-wired into the genes" -- as a possible cause of these inherited traits. Because gene expression is impacted by environmental and lifestyle factors, this finding suggests that individuals with obese fathers may be able to proactively address health concerns.

June 11, 2013

Reversal of the Black Widow myth: Some male spiders prefer to eat old females rather than mate with them

The Black Widow spider gets its name from the popular belief that female spiders eat their male suitors after mating. However, a new study has shown that the tendency to consume a potential mate is also true of some types of male spider. The study by Lenka Sentenska and Stano Pekar from Masaryk University in the Czech Republic finds that male spiders of the Micaria sociabilis species are more likely to eat the females than be eaten. The paper, published in Springer's journal Behavioral Ecology and Sociobiology, outlines possible reasons for this behavior.

In nature, female choice of mate is commonly seen as the overriding factor affecting male mating success. Sexual cannibalism is a form of female mate choice with low-quality mates more likely to be cannibalized. However, there is not as much evidence about how males may sometimes dictate the choice of partner. The researchers suggest that in the Micaria sociabilis species, reverse cannibalism seen may be a type of male mate choice.

June 10, 2013

People are overly confident in their own knowledge, despite errors

Overprecision -- excessive confidence in the accuracy of our beliefs -- can have profound consequences, inflating investors' valuation of their investments, leading physicians to gravitate too quickly to a diagnosis, even making people intolerant of dissenting views. Now, new research confirms that overprecision is a common and robust form of overconfidence driven, at least in part, by excessive certainty in the accuracy of our judgments.

The research, conducted by researchers Albert Mannes of The Wharton School of the University of Pennsylvania and Don Moore of the Haas School of Business at the University of California, Berkeley, revealed that the more confident participants were about their estimates of an uncertain quantity, the less they adjusted their estimates in response to feedback about their accuracy and to the costs of being wrong.

"The findings suggest that people are too confident in what they know and underestimate what they don't know," says Mannes.

June 5, 2013

Energy drinks no better than caffeine, study suggests

Despite the "special blend" of ingredients, energy drinks work no better than ordinary caffeine at helping us pay attention, a new study suggests.

In the study, researchers examined participants' brain activity while they performed a task designed to require attention. Specifically, the researchers looked at how fast the brain responded to a change in letters appearing on a computer screen.


"A lot of people take the energy drinks because they think they have that extra boost over caffeine," said study researcher Chelsea Benham, a student at Centre College in Danville, Ky. But the study shows "there's really no difference," Benham said.

In terms of boosting attention, a cup of coffee "would do you just as well," if it had the same amount of caffeine as an energy drink, she said.

Helicopter takes to the skies with the power of human thought

A remote controlled helicopter has been flown through a series of hoops around a college gymnasium in Minnesota.

It sounds like your everyday student project; however, there is one caveat -- the helicopter was controlled using just the power of thought.

The experiments have been performed by researchers hoping to develop future robots that can help restore the autonomy of paralysed victims or those suffering from neurodegenerative disorders.

There were five subjects (three female, two male) who took part in the study and each one was able to successfully control the four-blade helicopter, also known as a quadcopter, quickly and accurately for a sustained amount of time.

June 3, 2013

Sleep deprived men over perceive women's sexual interest and intent

A new study suggests that one night of sleep deprivation leads to an increase in men's perceptions of both women's interest in and intent to have sex.

Results show that when they were well-rested, both men and women rated the sexual intent of women as significantly lower than that of men. However, following one night of sleep deprivation, men's rating of women's sexual intent and interest increased significantly, to the extent that women were no longer seen as having lower sexual intent than men. Sleep deprivation had no significant effect on variables related to commitment.

According to the authors, sleep deprivation is known to cause frontal lobe impairment, which has a negative effect on decision-making variables such as risk-taking sensitivity, moral reasoning and inhibition. However, this is the first study to investigate the impact of sleep deprivation on romantic and sexual decision-making.

Even with defects, graphene is strongest material in the world

In a new study, published in Science, Columbia Engineering researchers demonstrate that graphene, even if stitched together from many small crystalline grains, is almost as strong as graphene in its perfect crystalline form. This work resolves a contradiction between theoretical simulations, which predicted that grain boundaries can be strong, and earlier experiments, which indicated that they were much weaker than the perfect lattice.

Graphene consists of a single atomic layer of carbon, arranged in a honeycomb lattice. "Our first Science paper, in 2008, studied the strength graphene can achieve if it has no defects -- its intrinsic strength," says James Hone, professor of mechanical engineering, who led the study with Jeffrey Kysar, professor of mechanical engineering. "But defect-free, pristine graphene exists only in very small areas. Large-area sheets required for applications must contain many small grains connected at grain boundaries, and it was unclear how strong those grain boundaries were. This, our second Science paper, reports on the strength of large-area graphene films grown using chemical vapor deposition (CVD), and we're excited to say that graphene is back and stronger than ever."

Facebook profiles raise users' self-esteem and affect behavior

A Facebook profile is an ideal version of self, full of photos and posts curated for the eyes of family, friends and acquaintances. A new study shows that this version of self can provide beneficial psychological effects and influence behavior.

Catalina Toma, a UW-Madison assistant professor of communication arts, used the Implicit Association Test to measure Facebook users' self-esteem after they spent time looking at their profiles, the first time the social psychology research tool has been used to examine the effects of Facebook. The test showed that after participants spent just five minutes examining their own Facebook profiles, they experienced a significant boost in self-esteem. The test measures how quickly participants associate positive or negative adjectives with words such as me, my, I and myself.

"If you have high self-esteem, then you can very quickly associate words related to yourself with positive evaluations but have a difficult time associating words related to yourself with negative evaluations," Toma says. "But if you have low self-esteem, the opposite is true."

Asking for a precise number during negotiations can give you the upper hand

With so much on the line for job seekers in this difficult economic climate, a lot of new hires might be wondering how -- or whether at all -- to negotiate salary when offered a new position. A recently published study on the art of negotiation by two professors at Columbia Business School could help these new hires -- and all negotiators -- seal a stronger deal than before.

Research conducted by Professors Malia Mason and Daniel Ames and doctoral students Alice Lee and Elizabeth Wiley finds that asking for a specific and precise dollar amount versus a rounded-off dollar amount can give you the upper hand during any negotiation over a quantity.

"What we discovered is there is a big difference in what most people think is a good strategy when negotiating and what research shows is a good strategy," said Professor Mason. "Negotiators should remember that in this case, zero's really do add nothing to the bargaining table."