By Katherine Harmon It’s always nice to get the full recommended seven or nine hours of sleep every day. But life—and work—often gets in the way. And getting too little sleep can decrease attention and short-term memory and can also alter rational judgment—in addition to increasing the risk for some diseases and making it harder to lose weight. Thus, for those who work in an industry where a simple error can lead to injury or death, missing out on sleep can be seriously dangerous. Moreover, according to a new survey, workers in industries with heavy equipment are among the least likely to be well rested. A study of more than 15,000 employed U.S. adults shows that 30 percent of all workers reported getting fewer than six hours of sleep every day. That’s some 28.3 million workers who are operating (themselves and often machinery) with far less sleep than recommended. The findings were published online April 27 by the U.S. Centers for Disease Control and Prevention (CDC). Night shift workers were, predictably, the most likely to be getting less z’s, with 44 percent—some 2.2 million people—getting fewer than six hours a day. (Trying to sleep during daylight hours can be a challenge because the body’s circadian rhythms are more likely to be sending stay-awake hormonal signals.) Of people who work in transportation and warehousing on overnight shifts, almost 70 percent are getting fewer than six hours of sleep a day. This is of particular concern considering that at least one in five vehicle accidents is the result of a fatigued driver. © 2012 Scientific American

Keyword: Sleep
Link ID: 16722 - Posted: 04.28.2012

Sandrine Ceurstemont, editor, New Scientist TV Think your eyes can detect if an object is upright? A new illusion by video producer Greg Ross shows that it's not always the case as visual detail can sometimes fool our brain. In this video, a balance beam is filled in with a diagonal pattern. Does it seem to be skewed? Keep watching as the lines are slowly removed. Do you notice a difference when the drawing is white? The balance beam should look tilted when it's covered with lines but upright when they are erased. However, measuring the distance between the blocks would prove that the top and bottom are parallel in both cases. According to Ross, the effect is due to the opposing direction of diagonal lines in each rectangle. But the triangle placed on the right side of the top beam accentuates the effect. "We perceive it as weighing down on the right side but only when the diagonal lines are there," says Ross. A similar effect can be observed in other optical illusions, for example radiating lines covering a shape can make it appear to bend. Highlighting the corners of squares on a chessboard can also distort the alignment. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 16721 - Posted: 04.28.2012

By Jason Palmer Science and technology reporter, BBC News Researchers have spotted a group of 53 cells within pigeons' brains that respond to the direction and strength of the Earth's magnetic field. The question of how birds navigate using - among other signals - magnetic fields is the subject of much debate. These new "GPS neurons" seem to show how magnetic information is represented in birds' brains. However, the study reported by Science leaves open the question of how they actually sense the magnetic field. David Dickman of the Baylor College of Medicine in the US set up an experiment in which pigeons were held in place, while the magnetic field around them was varied in its strength and direction. Prof Dickman and his colleague Le-Qing Wu believed that the 53 neurons were candidates for sensors, so they measured the electrical signals from each one as the field was changed. Every neuron had its own characteristic response to the magnetic field, with each giving a sort of 3-D compass reading along the familiar north-south directions as well as pointing directly upward or downward. BBC © 2012

Keyword: Animal Migration
Link ID: 16720 - Posted: 04.28.2012

By NICHOLAS BAKALAR A randomized trial of steroid injections for back pain has shown that they are no more effective than a placebo. Because the long-term benefits of surgery remain unproven and pain medicines often have serious side effects, doctors have increasingly turned to steroid injections to treat lumbosacral radiculopathy, a common cause of back pain. The condition stems from damage to the discs between the vertebrae that often leads to sciatica, numbness or pain in the legs. Researchers tested 84 adults with back pain of less than six months’ duration, dividing them into three groups. They received either steroids, etanercept (an arthritis medicine) or an inactive saline solution in two injections given two weeks apart. At the end of one month, they were assessed for pain. Leg and back pain decreased in all three groups, but there were no statistically significant differences among them. The researchers conclude that steroids may provide some short-term analgesic effect, but that the improvement in all of the patients was mainly due to normal healing. The lead author, Dr. Steven P. Cohen, an associate professor of anesthesiology at Johns Hopkins, was disappointed with the results but said that he still hopes drugs like etanercept might someday be proven effective. But for now, he said, “the strongest evidence for back pain relief is with exercise.” Copyright 2012 The New York Times Company

Keyword: Pain & Touch
Link ID: 16719 - Posted: 04.28.2012

By Tina Hesman Saey A new treatment mimics acupuncture’s the pain-blocking mechanism of acupuncture but offers longer-lasting pain relief, at least in mice. Injections of an enzyme called PAP into an acupuncture point behind the knees of mice relieved pain caused by inflammation for up to six days, Julie Hurt and Mark Zylka of the University of North Carolina at Chapel Hill report online April 23 in Molecular Pain. That’s almost 100 times longer than pain relief from acupuncture, which typically lasts about 1½ hours. Long-lasting pain relief “is truly important, clinically,” says Maiken Nedergaard, a neuroscientist at the University of Rochester in New York. She and colleagues previously demonstrated that inserting and manipulating acupuncture needles causes the body to release a chemical called adenosine. Adenosine acts as a local anesthetic to slow down pain messages sent to the brain, she says. “The beauty of Mark’s study is that it takes advantage of the molecular mechanism of acupuncture and improves upon it,” Nedergaard says. Zylka had already been studying PAP, which stands for prostatic acid phosphatase, when Nedergaard’s research on the release of adenosine during acupuncture was published. The study gave him the idea that boosting adenosine at acupuncture points, which are located where nerves contact muscle, could be a localized way to treat pain. Adenosine lasts only minutes in the human body, so injections of the chemical itself were not an option. © Society for Science & the Public 2000 - 2012

Keyword: Pain & Touch
Link ID: 16718 - Posted: 04.28.2012

By GRETCHEN REYNOLDS ONE lesson I’ve learned while writing about fitness is that few things impinge on an active life as much as writing about fitness — all that time spent hunched before a computer or puzzling over scientific journals, the countless hours of feckless, seated procrastination. While writing about the benefits of exercise, my muscles slackened. Fat seeped insidiously into my blood, liver and ventricles. Stupor infiltrated my brain. We all know by now that being inactive is unhealthy. But far too many of us think that being inactive is something that happens to other people. Studies of daily movement patterns, though, show that your typical modern exerciser, even someone who runs, subsequently sits for hours afterward, often moving less over all than on days when he or she does not work out. The health consequences are swift, pervasive and punishing. In a noteworthy recent experiment conducted by scientists at the University of Massachusetts and other institutions, a group of healthy young men donned a clunky platform shoe with a 4-inch heel on their right foot, leaving the left leg to dangle above the ground. For two days, the men hopped about using crutches (and presumably gained some respect for those people who regularly toddle about in platform heels). Each man’s left leg never touched the ground. Its muscles didn’t contract. It was fully sedentary. © 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 16717 - Posted: 04.28.2012

by Daniel Strain Sharks may be known as terrors of the sea, but in some cases they're more like night lights. That's because many deep-sea sharks, like the smalleye pygmy shark (Squaliolus aliae), can make their own light, glowing from tail to snout as a possible means of camouflage. Now, a new study shows how this predator, the world's smallest shark, powers its luminescence. Smalleye pygmy sharks aren't just petite—they grow no more than 22 centimeters long—they're also hard to find, says study co-author Julien Claes, a shark biologist at the Catholic University of Louvain in Belgium. These fish swim hundreds of meters below the water's surface in the Indian and western Pacific oceans. When scientists do manage to pull one of these animals up, they sometimes catch an odd sight: a blue glow coming mostly from the shark's belly. Claes co-authored a paper in 2009 that showed that a second group of luminescent sharks, called lantern sharks (Etmopterus spinax), trigger their own glow using two hormones common in many animals: melatonin and prolactin. But it wasn't clear if smalleye pygmy sharks and their close relatives relied on the same molecules. So Claes and his colleagues launched a second survey, collecting 27 pygmy sharks off the coast of Taiwan. To determine what controlled their unearthly glow, the researchers took patches of the fish's skin and soaked them in various chemicals known to cue luminescence in other species. They then recorded the resulting glow—often so faint that it was tricky to see at a distance even in a dark room—using a light detector. And sure enough, when Claes tried melatonin, which in people helps to control cycles of sleep and waking, voila! There was light. © 2010 American Association for the Advancement of Science.

Keyword: Hormones & Behavior; Biological Rhythms
Link ID: 16716 - Posted: 04.26.2012

National Institutes of Health researchers have reversed behaviors in mice resembling two of the three core symptoms of autism spectrum disorders (ASD). An experimental compound, called GRN-529, increased social interactions and lessened repetitive self-grooming behavior in a strain of mice that normally display such autism-like behaviors, the researchers say. GRN-529 is a member of a class of agents that inhibit activity of a subtype of receptor protein on brain cells for the chemical messenger glutamate, which are being tested in patients with an autism-related syndrome. Although mouse brain findings often don't translate to humans, the fact that these compounds are already in clinical trials for an overlapping condition strengthens the case for relevance, according to the researchers. "Our findings suggest a strategy for developing a single treatment that could target multiple diagnostic symptoms," explained Jacqueline Crawley, Ph.D., of the NIH’s National Institute of Mental Health (NIMH). "Many cases of autism are caused by mutations in genes that control an ongoing process — the formation and maturation of synapses, the connections between neurons. If defects in these connections are not hard-wired, the core symptoms of autism may be treatable with medications." Crawley, Jill Silverman, Ph.D., and colleagues at NIMH and Pfizer Worldwide Research and Development, Groton, CT, report on their discovery April 25th, 2012 in the journal Science Translational Medicine.

Keyword: Autism
Link ID: 16715 - Posted: 04.26.2012

by Anil Ananthaswamy Is our ability to map numbers onto a physical space – such as along a line – a cultural invention rather than an innate ability? Members of a remote tribe in Papua New Guinea understand the concept of numbers but do not map them along a line, which suggests that the 'number line' must be learned. Researchers have long thought that the human brain is hard wired to associate numbers with physical space, and we naturally associate numbers with physical space. The idea received a boost in 2002 when it was discovered that people with brain damage who were unable to fully perceive one side of their body had trouble interpreting the number line – they claimed, for example, that five lies between three and six (Nature, DOI:10.1038/417138a). In 2008, Stanislas Dehaene of the National Institute of Health and Medical Research (INSERM) in Saclay, France, and colleagues found a subtle variation of the concept in the Mundurucu, an indigenous group in the Amazon with little or no formal education. The Mundurucu map numbers on to a line, but use a logarithmic scale rather than a typical linear scale – they allow plenty of room for small numbers but scrunch larger numbers together at the far end of the line. The finding suggested that the linear number line is a cultural invention, but the number line itself remained intact as an intuition shared by all humanity (Science, DOI: 10.1126/science.1156540). © Copyright Reed Business Information Ltd

Keyword: Attention
Link ID: 16714 - Posted: 04.26.2012

By Laura Sanders Tiny eye movements and blinking can make perfectly frozen snakes appear to dance, a new study shows. The results help explain the mystery of how the Rotating Snakes illusion tricks the brain. Earlier studies have suggested that the perception of motion is triggered by the eyes drifting slowly away from a central target when viewing the illusion. But by tracking eye movements in eight volunteers, vision neuroscientists at the Barrow Neurological Institute in Phoenix found a different explanation. Participants held down a button when the snakes seemed to swirl and lifted the button when the snakes appeared still. Right before the snakes started to move, participants began blinking more and making short jumpy eye movements called microsaccades, Jorge Otero-Millan, Stephen Macknik and Susana Martinez-Conde report in the April 25 Journal of Neuroscience. When volunteers’ rates of microsaccades slowed down, the visual illusion faded and the snakes were more likely to stop moving. The results join a growing number of studies that use magic tricks and illusions to reveal people’s perceptual mistakes, such as seeing motion where there is none. Studying the mismatch between perception and reality may lead to a deeper understanding of the mind. © Society for Science & the Public 2000 - 2012

Keyword: Vision
Link ID: 16713 - Posted: 04.26.2012

By GRETCHEN REYNOLDS Ferrets don’t often figure in studies of exercise, perhaps because they don’t exercise much. They slink like fog through tunnels, sprint briefly over open ground and spend much of their time sleeping. They are, in biological terms, what’s called a noncursorial species, meaning that they are reluctant and lousy distance runners. Which is why they were ideal subjects for a new experiment conducted at the University of Arizona in Tucson looking at whether humans and other species evolved to like running. Many anthropologists and distance runners believe that running guided the evolution of early humans. We ran in search of dinner and away from predators. But running is costly, metabolically. It incinerates energy. It can also cause injury. A twisted ankle would have removed your typical early human from the gene pool. So why did our ancestors continue to run over the millennia “and not evolve other strategies for survival?” asks David A. Raichlen, a professor of anthropology at the University of Arizona, who led the study, which was published in The Journal of Experimental Biology. “We wondered if natural selection might have used neurobiological mechanisms to encourage exercise activity,” he continues. Specifically, he and his colleagues became interested in the evolutionary role of the endocannabinoid system. As the name suggests, endocannabinoids are chemicals that, like cannabis in marijuana, alter and lighten moods. But the body produces endocannabinoids naturally. In other studies, endocannabinoid levels have been shown to increase after prolonged running and cycling, leading many scientists to conclude that endocannabinoids help to create runner’s high. Copyright 2012 The New York Times Company

Keyword: Drug Abuse
Link ID: 16712 - Posted: 04.26.2012

By Robin Nixon LONDON — A seemingly trivial task – playing a particular video game – may lessen flashbacks and other psychological symptoms following a traumatic event, according to research presented here at the British Psychology Society Annual Conference. Researchers are now corroborating what some trauma sufferers have happened upon by chance: Focusing on a highly engaging visual-spatial task, such as playing video games, may significantly reduce the occurrence of flashbacks, the mental images concerning the trauma that intrude on the sufferer afterward. Flashbacks are considered by some to be the central hub of symptoms associated with post-traumatic stress disorder (PTSD), researchers Lalitha Iyadurai and Ella James of Oxford University explained to LiveScience. They are invasive, unpredictable distress signals that can make everyday activities difficult. The jarring mental images also may trigger or exacerbate other symptoms associated with PTSD, including irritability, anger, poor concentration and sleep disorders. [Top 10 Spooky Sleep Disorders] Reducing the occurrence of flashbacks is therefore likely to relieve post-traumatic suffering while leaving the actual memories of the trauma in place, they said. Iyadurai stressed the new research does not suggest a video game can instantly cure PTSD, but that it does suggests alternative treatments for the symptoms. © 2012 Scientific American

Keyword: Stress
Link ID: 16711 - Posted: 04.26.2012

by Elizabeth Norton Add this to the list of reasons not to take cocaine: Chronic use of the drug may speed up the aging process. According to a new imaging study, cocaine abusers in their 30s and 40s show brain changes more commonly seen in people over 60. The finding also calls attention to the special medical needs of older drug users—a group that, until now, hasn't garnered much notice. "Drug abuse is typically considered a young people's problem," says behavioral neuroscientist Karen Ersche at the University of Cambridge in the United Kingdom. But baby boomers, many of whom began experimenting with drugs when they were young, are getting older. And according to Ersche's research, some of them may be getting older faster. Studies show that middle-aged drug abusers often have problems more commonly seen in the elderly, such as memory loss, increased susceptibility to infection, and higher rates of cardiovascular disease. Rates of premature death among drug abusers are up to eight times higher than in the general population, according to some estimates. People addicted to cocaine also perform poorly on tasks that involve an area of the brain called the prefrontal cortex, such as memory, attention, and reaction time. Because elderly people can have similar mental impairments, Ersche wondered if chronic exposure to cocaine accelerates these changes in the brain. To investigate, she and colleagues studied 120 people between the ages of 18 and 50. About half met criteria for cocaine addiction: They had used cocaine for an average of 10 years and had the drug in their systems on the day of the scan, according to urine tests. © 2010 American Association for the Advancement of Science.

Keyword: Drug Abuse; Development of the Brain
Link ID: 16710 - Posted: 04.25.2012

by Katherine Rowland Traumatic experiences in early life can leave emotional scars. But a new study suggests that violence in childhood may leave a genetic mark as well. Researchers have found that children who are physically abused and bullied tend to have shorter telomeres—structures at the tips of chromosomes whose shrinkage has been linked to aging and disease. Telomeres prevent DNA strands from unravelling, much like the plastic aglets on a shoelace. When cells divide, these structures grow shorter, limiting the number of times a cell can reproduce. For this reason, telomeres may reflect biological age. Research has found associations between stress and accelerated telomere loss, and shortened telomeres correlate with several health problems, including diabetes, dementia, and fatigue. But the connection between telomere length and health and longevity is far from clear. "There's a lot of doubt in the field," notes Joao Passos, a cellular aging specialist at Newcastle University in the United Kingdom who was not involved in the research. "For as many studies that show telomere length as a good predictor of health outcomes, there are as many that find no relationship." Also unclear is whether childhood stress can affect telomere length. Almost all recent work on the topic has used retrospective data—that is, adults' recollections about their past. The new study examined children who were under stress to determine if they have shorter telomeres. © 2010 American Association for the Advancement of Science

Keyword: Stress; Epigenetics
Link ID: 16709 - Posted: 04.25.2012

By STEPHANIE STROM The Department of Agriculture announced that it had identified a case of mad cow disease, the first in six years, in a dairy cow in central California. The cow “was never presented for human consumption, so it at no time presented a risk to the food supply or human health,” John Clifford, chief veterinary officer at the department, said in a statement. Dr. Clifford noted that milk did not transmit bovine spongiform encephalopathy, the scientific name for mad cow disease. He expressed confidence in the health of the nation’s cattle and the safety of beef during a press briefing in Washington. The animal had been picked up from the farm and taken to a rendering plant, which noticed some of the signs of B.S.E., such as unsteadiness and aggression, and notified U.S.D.A. inspectors, Dr. Clifford said in a brief interview. The body will remain at the rendering facility and will be disposed of once the agency completes its investigation, probably by incineration or some other method that ensures the destruction of its tissues. It was the fourth reported case of mad cow disease, a degenerative disease that affects the brains and spinal cords of cattle, in the United States. Humans can contract the disease by eating meat from an infected cow. Only one case of mad cow disease in the United States was of the type derived from feed. That case set off a panic in 2003 when a Canadian-born cow in Washington state tested positive. © 2012 The New York Times Company

Keyword: Prions
Link ID: 16708 - Posted: 04.25.2012

By JOHN TAGLIABUE WEESP, the Netherlands — The sparkling-new 23-unit Hogewey complex here is virtually indistinguishable from other residential developments in the area. The apartments open onto a courtyard with benches, ponds and fountains, with beds of flowers in season (this is the Netherlands, after all). One kidney-shaped pond planted with reeds and other vegetation occasionally attracts wild ducks. There are plenty of amenities: a small supermarket, a theater and a restaurant and cafe that attract people from around the area. Again, nice, but nothing out of the ordinary. The residents can also participate in a variety of activities, like clubs for music, baking, painting and gardening. Yet, if Hogewey does not sound all that different from a typical residential complex, that is exactly the point. The residents are older men and women suffering from severe dementia, but instead of being constrained in a typical nursing home, they live here for $6,555 a month, six to eight to an apartment, where they are cared for by two or more trained professionals. The residents are confined to Hogewey for their own safety. But within the complex they are allowed to move around freely, to the extent that they are able. On a recent unseasonably chilly afternoon, the residents of one apartment, designated as “urban” to reflect its residents’ tastes, gathered around a dining room table for tea. Most sat quietly, smiling, some in wheelchairs. Jo Verhoef, a woman known as Aunt Jo, sat upright in a comfortable armchair. © 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 16707 - Posted: 04.25.2012

By TIMOTHY PRATT LAS VEGAS — One of the questions Dr. Charles Bernick and his colleagues ask boxers who come to the Cleveland Clinic’s Lou Ruvo Center for Brain Health here is, “How many times have you been knocked out cold or gotten a concussion?” Most say, “never.” Then the doctors ask, “How many times have you felt dazed and stunned?” Most say, “many times.” This is part of the Professional Fighters Brain Health Study, now a year old and with results from 109 fighters — more than have ever been compiled in a single research project. The principal finding: “There are detectable changes in the brain even before symptoms appear,” like memory loss or other changes in cognitive function resulting from repeated blows to the head, Dr. Bernick said. The physical changes, detected by M.R.I. scans, are a reduction in size in the hippocampus and thalamus of the brains of fighters with more than six years in the ring. These parts of the brain deal with such functions as memory and alertness. While those who had fought for more than six years did not exhibit any declines in cognitive function, fighters with more than 12 years in the ring did. Thus, Dr. Bernick’s group concluded, the lag between detectability and physical symptoms probably occurs sometime during those six years. © 2012 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 16706 - Posted: 04.25.2012

by Helen Thomson G marks the spot. Or does it? One researcher claims to have pinpointed and described the anatomy of the elusive G spot, an area of the vagina reputed to produce intense orgasms when stimulated. Many others are not so sure, saying that the G spot is unlikely to be a single structure. "It's akin to concluding that the Empire State Building is New York City," says Barry Komisaruk at Rutgers University in Newark, New Jersey. The G spot refers to an area on the front of the vaginal wall, a few centimetres from the entrance of the vagina. Stimulating this area is said to cause swelling and create an orgasm without stimulating the clitoris. As far back as the 11th century, ancient Indian texts described a sensitive area in the vagina inducing sexual pleasure. In 2008, Emmanuele Jannini at the University of L'Aquila in Italy discovered anatomical differences in the thickness of tissue in the region between the vagina and urethra in women who claimed to have vaginal orgasms compared with those who did not. However, a recent review of G spot research published since 1950 concluded that objective measures "have failed to provide strong and consistent evidence for the existence of an anatomical site related to the G spot" (The Journal of Sexual Medicine, DOI: 10.1111/j.1743-6109.2011.02623.x). © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 16705 - Posted: 04.25.2012

By Janelle Weaver A micrograph view of crystallized oxytocin. Image: Alfred Pasieka/Photo Researchers, Inc. When we meet new people, we assess their character by watching their gestures and facial expressions. Now a study in the Proceedings of the National Academy of Sciences USA suggests that those nonverbal cues are communicating the presence of a specific form of a gene that makes us more or less responsive to others’ needs. The gene determines which type of receptor a person has for the hormone oxytocin. Oxytocin has been implicated in a variety of positive traits, such as trust, empathy and generosity. The hormone is detected by our body’s cells via their oxytocin receptors. In a past study, psychologist Sarina Rodrigues Saturn of Oregon State University and her collaborators found that people who have a certain variation of the receptor gene are more empathetic than those with the alternative form of the gene. In the new study, Saturn and her team showed volunteers 20-second silent video clips of individuals who were listening to their romantic partner recount an upsetting experience. The study participants watched for nonverbal behaviors, such as head nods and smiles, and rated every individual on a number of character traits. Those with the form of the oxytocin receptor gene associated with empathy were judged by the volunteers as being more trustworthy, compassionate and kind than those with the alternative form of the gene. “These slight genetic variations do have a big impact on not only how you feel internally but also how people perceive you,” Saturn says, adding that impressions based on nonverbal cues can help individuals quickly choose compatible friends or romantic partners. © 2012 Scientific American,

Keyword: Hormones & Behavior; Genes & Behavior
Link ID: 16704 - Posted: 04.25.2012

By Deborah Kotz, Globe Staff With a social network of friends who are parents of school-age children like me, I’m amazed that I’ve never had a conversation about bedwetting. One of my friends alluded to it once, I think, when telling me why her 11-year-old never went to sleepovers. Unlike other topics that friends frequently ask me for information about as a health reporter, I’ve never been asked about bedwetting: what causes it, how to prevent it, and whether it ever resolves on its own. Perhaps it’s just too embarrassing to broach or seen as some sort of failure on the part of the child or parent. Yet bedwetting -- which becomes a medical condition called nocturnal enuresis after kids reach the age of five -- is far more common that you might think. About 6 percent of boys and 3 percent of girls ages 8 to 11 experience it at least two nights a week, and boys have more severe bedwetting than girls. Genetics also plays a role: A study published last year in the Journal of Urology found that the odds of a child being a severe bedwetter were nearly four times higher than average if the mother also had a history of bedwetting as a child. The reasons for why it occurs are usually physiological, not psychological: excessive urine production at night, overactive bladder, and failure to awaken in response to bladder sensations. “Each mechanism can be supported by various studies, and no one theory is likely to explain bedwetting in all children,” wrote Dr. Darcie Kiddoo, a pediatric urologist at the University of Alberta in Edmonton, in a review paper published Monday in the Canadian Medical Association Journal. © 2012 NY Times Co.

Keyword: Sleep
Link ID: 16703 - Posted: 04.25.2012