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James Gorman Dogs have evolved to be friendly and tolerant of humans and one another, which might suggest they would be good at cooperative tasks. Wolves are known to cooperate in hunting and even in raising one another’s pups, but they can seem pretty intolerant of one another when they are snapping and growling around a kill. So researchers at the Wolf Science Center at the University of Vienna decided to compare the performance of wolves and dogs on a classic behavioral test. To get a food treat, two animals have to pull ropes attached to different ends of a tray. The trick is that they have to pull both ropes at the same time. Chimps, parrots, rooks and elephants have all succeeded at the task. When Sarah Marshall-Pescini, Friederike Range and colleagues put wolves and dogs to the test, wolves did very well and dogs very poorly. In recordings of the experiments, the pairs of wolves look like experts, while the dogs seem, well, adorable and confused. The researchers reported their findings in the Proceedings of the National Academy of Sciences. With no training, five of seven wolf pairs succeeded in mastering the task at least once. Only one of eight dog pairs did. © 2017 The New York Times Company

Keyword: Attention; Evolution
Link ID: 24304 - Posted: 11.08.2017

April Fulton In the wake of the massacre at a small-town Texas church on Sunday, many people are asking why. A large portion of the mass shootings in the U.S. in recent years have roots in domestic violence against partners and family members. Depending on how you count, it could be upwards of 50 percent. We know the Texas gunman, Devin Patrick Kelley, was court-martialed for assaulting his wife and their young child in 2012, although this information apparently was not included in the formal government database that tracks such things. There are laws on the books preventing convicted domestic violence offenders from obtaining weapons. So why does this keep happening? There are no easy answers. NPR's Alison Kodjak recently talked with Daniel Webster, director of the Johns Hopkins Center for Gun Policy and Research in Baltimore, Md., about the complexities of gun violence, mass shootings, and the difficulty we have in understanding the people who commit these crimes. While perpetrators of domestic violence account for only about 10 percent of all gun violence, they accounted for 54 percent of mass shootings between 2009 and 2016, according to the advocacy group Everytown for Gun Safety, so there is a disproportionate link, Webster tells Kodjak. "Generally, it fits a pattern of easy access to firearms of individuals who have very controlling kind of relationships with their intimate partners and are greatly threatened when their control is challenged," he says. © 2017 npr

Keyword: Aggression
Link ID: 24303 - Posted: 11.08.2017

Jo Marchant Listen in: the words people say may reveal the body's biological response to threat. Subtleties in the language people use may reveal physiological stress. Psychologists found that tracking certain words used by volunteers in randomly collected audio clips reflected stress-related changes in their gene expression. The speech patterns predicted those physiological changes more accurately than speakers’ own ratings of their stress levels. The research, which is published on 6 November in Proceedings of the National Academy of Sciences1 suggests that changes in language may track the biological effects of stress better than how we consciously feel. It’s a new approach to studying stress, says David Creswell, a psychologist at Carnegie Mellon University in Pittsburgh, Pennsylvania, and one that “holds tremendous promise” for understanding how psychological adversity affects physical health. Adverse life circumstances — such as poverty, trauma or social isolation — can have devastating effects on health, increasing the risk of a variety of chronic disorders ranging from heart disease to dementia. Researchers trying to pin down the biological mechanisms involved have found that people who experience these circumstances also undergo broad changes in gene expression in the cells of their immune system. Genes involved in inflammation become more active, for example, and antiviral genes are turned down. © 2017 Macmillan Publishers Limited,

Keyword: Stress; Language
Link ID: 24302 - Posted: 11.07.2017

Jon Hamilton When people don't get enough sleep, certain brain cells literally slow down. A study that recorded directly from neurons in the brains of 12 people found that sleep deprivation causes the bursts of electrical activity that brain cells use to communicate to become slower and weaker, a team reports online Monday in Nature Medicine. The finding could help explain why a lack of sleep impairs a range of mental functions, says Dr. Itzhak Fried, an author of the study and a professor of neurosurgery at the University of California, Los Angeles. "You can imagine driving a car and suddenly somebody jumps in front of the car at night," Fried says. "If you are sleep-deprived, your cells are going to react in a different way than in your normal state." The finding comes from an unusual study of patients being evaluated for surgery to correct severe epilepsy. As part of the evaluation, doctors place wires in the brain to find out where a patient's seizures are starting. That allows Fried and a team of scientists to monitor hundreds of individual brain cells, often for days. And because patients with epilepsy are frequently kept awake in order to provoke a seizure, the scientists had an ideal way to study the effects of sleep deprivation. In the study, all the patients agreed to categorize images of faces, places and animals. Each image caused cells in areas of the brain involved in perception to produce distinctive patterns of electrical activity. "These are the very neurons [that] are responsible for the way you process the world in front of you," Fried says. © 2017 npr

Keyword: Sleep; Attention
Link ID: 24301 - Posted: 11.07.2017

By Anna Cranston, Around 50m people worldwide are thought to have Alzheimer’s disease. And with rapidly ageing populations in many countries, the number of sufferers is steadily rising. We know that Alzheimer’s is caused by problems in the brain. Cells begin to lose their functions and eventually die, leading to memory loss, a decline in thinking abilities and even major personality changes. Specific regions of the brain also shrink, a process known as atrophy, causing a significant loss of brain volume. But what’s actually happening in the brain to cause this? Advertisement The main way the disease works is to disrupt communication between neurons, the specialised cells that process and transmit electrical and chemical signals between regions of the brain. This is what is responsible for the cell death in the brain – and we think its due to a build up of two types of protein, called amyloid and tau. The exact interaction between these two proteins is largely unknown, but amyloid accumulates into sticky clusters known as beta-amyloid “plaques”, while tau builds up inside dying cells as “neurofibrillary tangles”. One of the difficulties of diagnosing Alzheimer’s is that we’ve no reliable and accurate way of measuring this protein build-up during the early stages of the disease. In fact, we can’t definitively diagnose Alzheimer’s until after the patient has died, by examining their actual brain tissue. Another problem we have is that beta-amyloid plaques can also be found in the brains of healthy patients. This suggests the presence of the amyloid and tau proteins may not tell the whole story of the disease. © 2017 Scientific American,

Keyword: Alzheimers
Link ID: 24300 - Posted: 11.07.2017

For the first time, scientists have found a connection between abnormalities in how the brain breaks down glucose and the severity of the signature amyloid plaques and tangles in the brain, as well as the onset of eventual outward symptoms, of Alzheimer’s disease. The study was supported by the National Institute on Aging (NIA), part of the National Institutes of Health, and appears in the Nov. 6, 2017, issue of Alzheimer's & Dementia: the Journal of the Alzheimer's Association. Led by Madhav Thambisetty, M.D., Ph.D., investigator and chief of the Unit of Clinical and Translational Neuroscience in the NIA’s Laboratory of Behavioral Neuroscience, researchers looked at brain tissue samples at autopsy from participants in the Baltimore Longitudinal Study of Aging (BLSA), one of the world’s longest-running scientific studies of human aging. The BLSA tracks neurological, physical and psychological data on participants over several decades. Researchers measured glucose levels in different brain regions, some vulnerable to Alzheimer’s disease pathology, such as the frontal and temporal cortex, and some that are resistant, like the cerebellum. They analyzed three groups of BLSA participants: those with Alzheimer’s symptoms during life and with confirmed Alzheimer’s disease pathology (beta-amyloid protein plaques and neurofibrillary tangles) in the brain at death; healthy controls; and individuals without symptoms during life but with significant levels of Alzheimer’s pathology found in the brain post-mortem. They found distinct abnormalities in glycolysis, the main process by which the brain breaks down glucose, with evidence linking the severity of the abnormalities to the severity of Alzheimer’s pathology. Lower rates of glycolysis and higher brain glucose levels correlated to more severe plaques and tangles found in the brains of people with the disease. More severe reductions in brain glycolysis were also related to the expression of symptoms of Alzheimer’s disease during life, such as problems with memory.

Keyword: Alzheimers
Link ID: 24299 - Posted: 11.07.2017

By Roni Dengler The bills of even newly hatched ducks might be as sensitive as our hands, as touch sensors in their beaks are as abundant as those in our fingertips and palms. That’s the take-away of new research published today in the Proceedings of the National Academy of Sciences that describes the origins of touchiness in the common duck’s quacker. Researchers knew that duck bills can sense light touch but have muted responsiveness to temperature. This comes in handy (or bill-y) since the birds forage for food in cold, murky bottom waters. Now, researchers find the sensors duck bills use to perceive touch work even before hatching. That likely helps young ducklings scavenge for food alongside adults soon after birth. In keeping with the need to feel for food, the ducks have more nerve cells to relay touch signals than chickens, which rely on eyesight to find sustenance, they report. That means different developmental programs are at work in ducks and chickens, which could help scientists uncover how touch evolved. Because the duck’s touch sensors are similar to mammals’ and their bills aren’t covered in fur, the authors suggest embryonic duck bills might be a better model than standard laboratory rodents to study touch sensation as it applies to us relatively hairless humans. © 2017 American Association for the Advancement of Science

Keyword: Pain & Touch; Development of the Brain
Link ID: 24298 - Posted: 11.07.2017

By LAURA HILGERS San Anselmo, Calif. — Fay Zenoff recently met a friend for dinner at a sushi restaurant in Sausalito, Calif. After they were seated, a waitress asked if they’d like wine with dinner. Her friend ordered sake. Ms. Zenoff declined. “Not for me,” she said. “I’m celebrating 10 years of sobriety this weekend.” Because of the stigma attached to addiction, Ms. Zenoff, who is 50, took a risk speaking so openly. But when she and her friend finished eating, the waitress reappeared. This time she carried ice cream with a candle in it and was accompanied by fellow members of the restaurant staff. They stood beside Ms. Zenoff’s table, singing “Happy Birthday.” The evening, Ms. Zenoff recalled, was “just amazing.” A victory, too. For 25 years, Ms. Zenoff, who began adult life with an M.B.A. from Northwestern, was an alcoholic who dabbled in heroin, Ecstasy and cocaine. “I felt so much shame about my past behavior,” she said, “that it was a huge hurdle to admit I was in recovery even to my family and friends.” It took three years for her to speak up among friends and another three for her to do so publicly. Now as executive director of the Center for Open Recovery, a Bay Area nonprofit, she’s promoting an idea considered radical in addiction circles: that people in recovery could be open and even celebrated for managing the disease that is plaguing our nation. She and other advocates believe that people in recovery could play a vital role in ending the addiction epidemic, much as the protest group Act Up did in the AIDS crisis. It’s an idea that fits with the report released by President Trump’s opioid commission last week. Among the report’s 56 recommendations was a suggestion that the government battle stigma and other factors by partnering with private and nonprofit groups on a national media and educational campaign similar to those “launched during the AIDS public health crisis.”

Keyword: Drug Abuse
Link ID: 24297 - Posted: 11.06.2017

By Rachel Hoge I was waiting in line at my bank’s drive-up service, hoping to make a quick withdrawal. I debated my options: two vacant service lines and one busy one for the ATM. The decision was easy: Wait in the line and deal with a machine. I have a speech disability — a stutter — and interactions with strangers have the potential to be, at the very least, extremely awkward; at worst, I have been mocked, insulted, misjudged or refused service. I avoid interacting with new people, fearful of their judgment. Using the ATM offered me more than just convenience. But the ATM, I soon discovered, was going down for maintenance. I could either leave, returning on a day when the machine was back in service, or speak with a bank teller. Once again, I debated my options. I needed the cash and I was feeling optimistic, so I pulled into the service line. I quickly rehearsed all acceptable variations of what I had to say: I need to withdraw some money from my checking account. Or maybe, to use fewer words: Could I have a withdrawal slip? Or straight to the point: Withdraw, please. Rachel Hoge would rather be treated with patience than with pity. (Katy Nash) I pulled my car forward. Glancing at the teller, I took a deep breath and managed to blurt out: “Can I ppppplease make a wi-wi-with-with-withdrawal?” The teller smiled on the other side of the glass. “Sure,” she said. I wasn’t sure if she had noticed my stutter or simply believed my repetitions (rep-rep-repetitions) and prolongations (ppppprolongations) were just indications of being tongue-tied rather than manifestations of a persistent stutter. I eased back in my seat, trying to relax. © 1996-2017 The Washington Post

Keyword: Language
Link ID: 24296 - Posted: 11.06.2017

Laura Sanders An Alzheimer’s-related protein can move from the blood to the brain and accumulate there, experiments on mice show for the first time. The results, published online October 31 in Molecular Psychiatry, suggest that the protein amyloid-beta outside the brain may contribute to the Alzheimer’s disease inside it, says Mathias Jucker, a neurobiologist at the University of Tübingen in Germany. This more expansive view of the disease may lead scientists to develop treatments that target parts of the body that are easier than the brain to access. The experiments don’t suggest that people could contract Alzheimer’s from another person’s blood. “The bottom line is that this study is thought-provoking but shouldn’t cause alarm,” says neurologist John Collinge of University College London. “There really isn’t any evidence that you can transmit Alzheimer’s disease by blood transfusion.” But researchers wondered whether, over time, A-beta might build up in the brain by moving there from the blood, where it’s normally found in small quantities. Earlier animal studies have shown that A-beta can move into the brain if it’s injected into the bloodstream, but scientists didn’t know whether A-beta from the blood can be plentiful enough to form plaques in the brain. To test this, researchers used a form of extreme blood-sharing in the experiment. Six pairs of mice — with one mouse engineered to produce gobs of human A-beta and one normal — were surgically joined for a year, causing blood mingling that’s far more extensive than that of a blood transfusion. After a year, the brains of the mice carrying the mutations were full of A-beta plaques, as expected. But these plaques were also inside the brains of the normal mice in the joined pairs. |© Society for Science & the Public 2000 - 2017.

Keyword: Alzheimers
Link ID: 24295 - Posted: 11.06.2017

By JANE E. BRODY Modern technology is making it possible for medical scientists to analyze inhabitants of our innards that most people probably would rather not know about. But the resulting information could one day save your health or even your life. I’m referring to the trillions of bacteria, viruses and fungi that inhabit virtually every body part, including those tissues once thought to be sterile. Together, they make up the human microbiome and represent what is perhaps the most promising yet challenging task of modern medicine: Determining the normal microscopic inhabitants of every organ and knowing how to restore the proper balance of organisms when it is disrupted. Proof of principle, as scientists call it, has already been established for a sometimes devastating intestinal infection by the bacterium Clostridium difficile. This infection, popularly called C. diff, often occurs when potent antibiotics wipe out the normal bacterial inhabitants of the gut that otherwise keep it in check. When all else fails to clear up a recurrent C. diff infection, the Food and Drug Administration has approved treatment with a fecal transplant from a healthy gut presumed to contain bacteria that can suppress C. diff activity. The treatment is highly effective, with a cure rate in excess of 90 percent. Under the auspices of the National Institutes of Health, a large team of scientists is now engaged in creating a “normal” microbiological road map for the following tissues: gastrointestinal tract, oral cavity, skin, airways, urogenital tract, blood and eye. The effort, called the Human Microbiome Project, takes advantage of new technology that can rapidly analyze large samples of genetic material, making it possible to identify the organisms present in these tissues. © 2017 The New York Times Company

Keyword: Obesity
Link ID: 24294 - Posted: 11.06.2017

Hannah Devlin Science correspondent British scientists have begun testing a radically new approach to treating schizophrenia based on emerging evidence that it could be a disease of the immune system. The first patient, a 33-year old man who developed schizophrenia after moving to London from Cameroon a decade ago, was treated at King’s College Hospital in London on Thursday, marking the start of one of the most ambitious trials to date on the biology of the illness and how to treat it. During the next two years, 30 patients will receive monthly infusions of an antibody drug currently used to treat multiple sclerosis (MS), which the team hopes will target the root causes of schizophrenia in a far more fundamental way than current therapies. The trial builds on more than a decade’s work by Oliver Howes, a professor of molecular psychiatry at the MRC London Institute of Medical Sciences and a consultant psychiatrist at the Maudsley Hospital in south London. Howes’s team is one of several worldwide to have uncovered evidence that abnormalities in immune activity in the brain may lie at the heart of the illness – for some patients, at least. “In the past, we’ve always thought of the mind and the body being separate, but it’s just not like that,” said Howes. “The mind and body interact constantly and the immune system is no different. It’s about changing the way we think about mental illnesses.” Recent work by Howes and colleagues found that in the earliest stages of schizophrenia, people experience a surge in the number and activity of immune cells in the brain. As well as fighting infection, these cells, called microglia, have a “gardening” role, pruning unwanted connections between neurons. But in schizophrenia patients, the pruning appears to become more aggressive, leading to vital connections being lost. © 2017 Guardian News and Media Limited

Keyword: Schizophrenia; Neuroimmunology
Link ID: 24293 - Posted: 11.04.2017

Hannah Devlin Descartes’s notion of dualism – that the mind and body are separate entities – is wrong, but has proved surprisingly persistent, and until recently dominated attempts to understand mental illness. When the brain stopped working properly, a psychological origin was sought. Undoubtedly, life’s experiences and our personalities shape the way our brains function. But there is now a compelling body of evidence that brain disorders can also originate from things going awry in our basic biology. Particularly intriguing is the discovery that the brain, once thought to be separated from the immune system by the blood-brain barrier, is powerfully influenced by immune activity. The latest trial, focused on schizophrenia, is backed by converging evidence from several fields that immune cells in the brain, called microglia, play at least some role in this disease. Prof Oliver Howes, the psychiatrist leading the work, discovered that these cells appear to go into overdrive in the early stages of schizophrenia. Genetics studies have linked changes in immune system genes to increased risk for schizophrenia and anecdotal evidence, including a recent case report of a patient who developed schizophrenia after receiving a bone marrow transplant from a sibling with the illness, also triangulates on to the immune system. “It’s all challenging the idea that the brain is this separate privileged organ,” said Howes. © 2017 Guardian News and Media Limited

Keyword: Schizophrenia
Link ID: 24292 - Posted: 11.04.2017

By James T. Costa One day in May of 1840, a young scientist in London did something that will sound strange to any new parent: He deliberately startled his 4-month-old son, provoking piercing squalls from the baby and probably a baleful glare from his wife. Then he did it again. Darwin remains best known for his world-shaking theories on plant and animal evolution. But people were never far from his mind. The scientist was Charles Darwin, and the experiment on his son Willy turned out to be an often-overlooked landmark in the history of science. Darwin, then just 31 years old, had become a convert to the field of “transmutation,” as evolution was called then, and had experienced an epiphany when he discovered its driver, which he dubbed natural selection. The former theology student immediately grasped the implications of this theory, declaring that the theological interpretation of the natural world had been undone by scientific evidence — “The fabric falls!” as he put it in a notebook. And while Darwin remains best known for his world-shaking theories on plant and animal evolution, as put forward in the 1859 book “On the Origin of Species,” people and society were never far from his mind. Convinced of the evolutionary unity of life, Darwin naturally saw humans as part of the tapestry: They were animals too, after all. (Carl Linnaeus may have been deliberately provocative when, in 1758, he derived the taxonomic name “primates” from the Latin for “prime” or “first rank,” to refer not only to humans but to monkeys and apes; it also happened to be the term applied to bishops.) The standard view of the time was that, despite superficial similarities, there was no true relationship between humans and other primates, let alone other animals. Weren’t we humans clearly endowed with a soul and mental qualities that set us apart from and above the animal kingdom? But Darwin saw deeper significance in the family relationship, one of continuity, common descent. To him, there was no real gap between people and primates — differences, yes, but of degree and not kind. “Origin of man now proved,” he declared in 1838. “He who understands baboon would do more towards metaphysics than Locke.” Copyright 2017 Undark

Keyword: Emotions; Evolution
Link ID: 24291 - Posted: 11.04.2017

By Alfonso Serrano James Casey recalls having a fondness for fireworks while growing up on the outskirts of small towns in rural Louisiana and North Carolina. That was before his 2011 deployment as a U.S. Army medic to Kandahar, Afghanistan, where he was steadily exposed to the trauma of modern warfare. After he returned to the U.S. a year later at age 19, the sound of fireworks and similar blasts of noise produced ghastly images of the lifeless Kandahar patients who proved beyond his medical aid, mangled bodies that at times covered his entire field of view. Like nearly 30 percent of Afghanistan and Iraq War veterans, Casey was diagnosed with post traumatic stress disorder, which he sought to quell with everything from medication to group therapy to hypnosis. Nothing worked. After 18 months Casey was ready to accept his PTSD as a life sentence, he says. Then he read about upcoming trials of MDMA-assisted psychotherapy for PTSD patients in Boulder, Colorado, where he was headed to study molecular biology. “It gave me my life back,” he says, recalling the phase II trial organized in 2015 by the Multidisciplinary Association for Psychedelic Studies, or MAPS, in which Casey underwent three MDMA-assisted psychotherapy sessions over five weeks. “I did a year and a half of therapy before MDMA,” he says. “But with MDMA it was like a year and a half of the previous therapy in one day.” © 2017 Scientific American

Keyword: Drug Abuse; Stress
Link ID: 24289 - Posted: 11.04.2017

BC's Hogan twins, featured in the documentary Inseparable, are unique in the world. Joined at the head, their brains are connected by a thalamic bridge which gives them neurological capabilities that researchers are only now beginning to understand. Still, they are like other Canadian ten-year-olds; they attend school, have a favourite pet and are part of a large, loving family determined to live each day to the fullest. Here are a few highlights: Craniopagus twins, joined at the head, are a rarity — one in 2.5 million. The vast majority do not survive 24 hours. Krista and Tatiana Hogan were born October 25, 2006, in Vancouver, B.C. A CT scan of the twins showed they could never be separated due to the risk of serious injury or death. The structure of the twins’ brains makes them unique in the world. Their brains are connected by a thalamic bridge, connecting the thalamus of one with that of the other. The thalamus acts like a switchboard relaying sensory and motor signals and regulating consciousness. Krista and Tatiana Hogan share the senses of touch and taste and even control one another’s limbs. Tatiana can see out of both of Krista’s eyes, while Krista can only see out of one of Tatiana’s. Tatiana controls three arms and a leg, while Krista controls three legs and an arm. They can also switch to self-control of their limbs. The twins say they know one another’s thoughts without having to speak. “Talking in our heads” is how they describe it. The girls are diabetic and have epilepsy. They take a regimen of pills, blood tests and need daily insulin injections. The twins go to a regular school and as of September 2017 have started Grade 6. Though academically delayed, they are learning to read, write and do arithmetic. ©2017 CBC/Radio-Canada.

Keyword: Development of the Brain; Consciousness
Link ID: 24288 - Posted: 11.04.2017

By Emily Willingham In their October 23 opinion piece “Why Does Autism Impact Boys More Often Than Girls?” Renee Joy Dufault and Steven G. Gilbert attempt to argue that autism diagnoses are on the increase because of inorganic mercury content in processed foods. Going a step further, they try to construct a rationale for blaming mercury for the perceived bias in autism rates among boys compared to girls. Using the example of one observational study reporting that mercury affects chemical tagging of a single gene in one cell type differently in boys and girls, the pair constructs a fragile chain of putative links between this single study and their claim that “inorganic mercury has been rising for many years in American blood.” The claims are problematic on many levels, but let’s just take a trip to the ground floor: evidence. First, mercury levels in “American blood” and urine are decreasing, not increasing. The latest analysis of values of inorganic mercury in urine and total blood mercury, published online September 6 in Environmental Toxicology and Pharmacology, finds that from 2005 to 2012 among all age groups, urinary inorganic mercury decreased. Total blood mercury, which includes organic (carbon-bound) and inorganic forms, also decreased in all age groups during that time. These conclusions are based on data from the U.S. Centers for Disease Control and Prevention (CDC) National Health and Nutrition Examination Survey (NHANES). Meanwhile, other CDC data indicate that autism prevalence has increased. The trends for autism prevalence and mercury levels in people living in the United States are in opposite directions. © 2017 Scientific American

Keyword: Autism; Neurotoxins
Link ID: 24287 - Posted: 11.04.2017

By Giorgia Guglielmi The popular claim that women in their fertile days prefer men with more masculine faces may not be true. That’s the conclusion of the largest study to analyze how sex hormones influence women’s preference for men’s faces. Researchers first created 10 prototype male faces by averaging 50 photos of young white men. Then, they tweaked the prototype faces to create a more masculine and a more feminine version of each (pictured, masculine version on the left, feminine version on the right). Finally, the scientists asked nearly 600 heterosexual women to look at these photos and rate men’s attractiveness for either a fling or a long-term relationship. The women also provided saliva samples, which the researchers tested for sex hormones such as estradiol and testosterone. Hormone levels were not significantly related to women’s preference for manly faces, the team reports on the preprint server bioRxiv. The researchers also didn’t find evidence that women using the birth control pill prefer more feminine faces, as had been suggested. However, women did prefer masculine faces over feminine ones, especially for short-term relationships. This could be because manly traits, like a large jaw and jutting cheekbones, signal good heritable characteristics, such as a strong immune system, but have also been linked to people that are less willing to invest time in personal relationships, the scientists say. © 2017 American Association for the Advancement of Scien

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 24286 - Posted: 11.04.2017

By NICHOLAS ST. FLEUR Swallowed by a sinkhole. Washed away by a mudflow. Drowned after falling through thin ice. These are the fates that many unlucky mammoths suffered in Siberia thousands of years ago. Their well-preserved fossils have provided paleobiologists with insight into their prehistoric lives. Now, after performing a genetic analysis on the remains from the furry victims of natural traps, a team of scientists made a striking discovery: Most were male. “In many species, males tend to do somewhat stupid things that end up getting them killed in silly ways, and it appears that may have been true for mammoths also,” said Love Dalén, an evolutionary biologist from the Swedish Museum of Natural History. In a study published Thursday in the journal Current Biology, he and his colleagues analyzed DNA from nearly 100 mammoth bones, teeth and tusks, and found that about two-thirds came from males. They speculate the reason for the skewed sex-ratio may have to do with the risky behavior that young males take after leaving the protection of their mothers to live on their own. “Old females are very knowledgeable, they know best,” he said. The finding was an accident, according to Patrícia Pečnerová, a doctoral student at Stockholm University and lead author on the study. It came while she was entering data for a different project on mammoth genetics. “While filling this in on the spreadsheet we saw that there were too many males, more than there should be,” she said. “We were really surprised to see there were more than twice as many males as females because there was no previous research or indication that that should be the case.” The 98 specimens that the team had analyzed came from across the northern part of Siberia and had been collected over the course of four decades. The oldest were more than 60,000 years old, and the youngest, a specimen known as “Lonely Boy,” was about 4,000 years old. The genetic data did not provide insight into how old the mammoths were when they died, only their sex. © 2017 The New York Times Company

Keyword: Sexual Behavior
Link ID: 24285 - Posted: 11.03.2017

JoNel Aleccia People who abhor the thought of being kept alive with feeding tubes or other types of artificial nutrition and hydration have, for years, had a way out: They could officially document their wishes to halt such interventions using advance directives. Even patients diagnosed with progressive dementia who are able to record crucial end-of-life decisions before the disease robs them of their mental capacity could write advance directives. But caregivers and courts have rarely honored patients' wishes to refuse food and fluids offered by hand. Margot Bentley, 85, of British Columbia, died last year. She was a retired nurse who had cared for dementia patients before being diagnosed with Alzheimer's in 1999. In 1991, she wrote a statement stipulating that she wanted no nourishment or liquids if she developed an incurable illness. However, the nursing home where she was a patient continued to spoon-feed her, despite her family's protests. A court ruling upheld the nursing home's action, saying that food is basic care that cannot be withdrawn. Nora Harris, 64, of Medford, Ore., died on Oct. 11 after an eight-year struggle with early-onset Alzheimer's disease. More than a year earlier, her husband had gone to court to stop caregivers from spoon-feeding Harris, who had an advance directive that called for no artificial nourishment or hydration. A judge declined, siding with officials who said the state was required to feed vulnerable adults. © 2017 npr

Keyword: Alzheimers
Link ID: 24284 - Posted: 11.03.2017