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By SARAH HALLBERG and OSAMA HAMDY Earlier this year, the Food and Drug Administration approved a new weight-loss procedure in which a thin tube, implanted in the stomach, ejects food from the body before all the calories can be absorbed. Some have called it “medically sanctioned bulimia,” and it is the latest in a desperate search for new ways to stem the rising tides of obesity and Type 2 diabetes. Roughly one-third of adult Americans are now obese; two-thirds are overweight; and diabetes afflicts some 29 million. Another 86 million Americans have a condition called pre-diabetes. None of the proposed solutions have made a dent in these epidemics. Recently, 45 international medical and scientific societies, including the American Diabetes Association, called for bariatric surgery to become a standard option for diabetes treatment. The procedure, until now seen as a last resort, involves stapling, binding or removing part of the stomach to help people shed weight. It costs $11,500 to $26,000, which many insurance plans won’t pay and which doesn’t include the costs of office visits for maintenance or postoperative complications. And up to 17 percent of patients will have complications, which can include nutrient deficiencies, infections and intestinal blockages. It is nonsensical that we’re expected to prescribe these techniques to our patients while the medical guidelines don’t include another better, safer and far cheaper method: a diet low in carbohydrates. Once a fad diet, the safety and efficacy of the low-carb diet have now been verified in more than 40 clinical trials on thousands of subjects. Given that the government projects that one in three Americans (and one in two of those of Hispanic origin) will be given a diagnosis of diabetes by 2050, it’s time to give this diet a closer look. © 2016 The New York Times Company
Keyword: Obesity
Link ID: 22645 - Posted: 09.12.2016
By David Grimm Depending on whom you ask, yesterday’s U.S. government workshop on the state of nonhuman primate research was either a raging success or a complete fiasco. The event, held at the National Institutes of Health (NIH) in Bethesda, Maryland, brought together dozens of scientists, veterinarians, and bioethicists to discuss how research on monkeys and related animals is contributing to human medicine and to review the welfare policies that surround this work. But observers differed widely on whether it accomplished what Congress had in mind when it told NIH to hold the event. “It was a great showcase of the importance nonhuman primates have played and continue to play in human health,” says Anne Deschamps, a senior science policy analyst at the Federation of American Societies for Experimental Biology in Bethesda, one of several scientific organizations that signed onto a white paper released in advance of the meeting that promoted the use of these animals in biomedical research. She contends that research on these animals has been critical for our understanding of HIV and the human brain. But the animal rights group People for the Ethical Treatment of Animals (PETA), whose lobbying efforts led to the workshop, says the meeting was supposed to determine whether monkeys and their relatives belong in laboratories in the first place. “It was an infomercial for the use of monkeys in experiments,” says PETA Senior Vice President Kathy Guillermo in Norfolk, Virginia. “It was a wasted opportunity.” © 2016 American Association for the Advancement of Science
Keyword: Animal Rights
Link ID: 22644 - Posted: 09.12.2016
By GRETCHEN REYNOLDS A busy brain can mean a hungry body. We often seek food after focused mental activity, like preparing for an exam or poring over spreadsheets. Researchers speculate that heavy bouts of thinking drain energy from the brain, whose capacity to store fuel is very limited. So the brain, sensing that it may soon require more calories to keep going, apparently stimulates bodily hunger, and even though there has been little in the way of physical movement or caloric expenditure, we eat. This process may partly account for the weight gain so commonly seen in college students. Scientists at the University of Alabama at Birmingham and another institution recently experimented with exercise to counter such post-study food binges. Gary Hunter, an exercise physiologist at U.A.B., oversaw the study, which was published this month in the journal Medicine & Science in Sports & Exercise. Hunter notes that strenuous activity both increases the amount of blood sugar and lactate — a byproduct of intense muscle contractions — circulating in the blood and augments blood flow to the head. Because the brain uses sugar and lactate as fuel, researchers wondered if the increased flow of fuel-rich blood during exercise could feed an exhausted brain and reduce the urge to overeat. Thirty-eight healthy college students were invited to U.A.B.’s exercise lab to determine their fitness and metabolic rates — and to report what their favorite pizza was. Afterward, they sat quietly for 35 minutes before being given as much of their favorite pizza as they wanted, which established a baseline measure of self-indulgence. At a later date, the volunteers returned and spent 20 minutes tackling selections from college and graduate-school entrance exams. Hunter says this work has been used in other studies “to induce mental fatigue and hunger.” Next, half the students sat quietly for 15 minutes, before being given pizza. The rest of the volunteers spent those 15 minutes doing intervals on a treadmill: two minutes of hard running followed by about one minute of walking, repeated five times. This is the sort of brief but intensive routine, Hunter says, that should prompt the release of sugar and lactate into the bloodstream. These students were then allowed to gorge on pizza, too. But by and large, they did not overeat. © 2016 The New York Times Company
Keyword: Obesity; Learning & Memory
Link ID: 22643 - Posted: 09.10.2016
By Karen Weintraub Researchers have long believed that problems with mitochondria—the power plants of cells—underlie some cases of Parkinson’s disease. Now a new study details those problems, and suggests that they may form a common thread linking previously unexplained cases of the disease with those caused by different genetic anomalies or toxins. Finding a common mechanism behind different suspected causes of Parkinson’s suggests that there might also be a common means to measure, treat or cure it, says Marco Baptista, research director at the nonprofit Michael J. Fox Foundation, a leading center for study and advocacy in the fight against Parkinson’s. The study, published Thursday in Cell Stem Cell, did identify a possible way to reverse the damage of Parkinson’s—but only in individual cells and fruit flies. Finding a treatment that does the same thing in people will be challenging, Baptista says. Roughly one million Americans have Parkinson’s disease, which is characterized by motor problems and can cause other symptoms including cognitive and gastrointestinal difficulties. About 1 to 2 percent of cases are linked to mutations in the LRRK2 gene, with far fewer associated with genes known as PINK1 and Parkin. Exposure to environmental factors such as toxic chemicals can also lead to Parkinson’s, although most cases have no obvious cause. In the new paper Xinnan Wang, an assistant professor of neurosurgery at Stanford University, and her colleagues show that mitochondria are underpowered in several types of Parkinson’s and that these mitochondria also release toxic chemicals. Looking at fly models of the disease as well as cells taken from patients, the researchers found that they could correct these problems and reverse neurodegeneration if they reduced levels of a protein involved in mitochondrial activity. © 2016 Scientific American
Keyword: Parkinsons
Link ID: 22642 - Posted: 09.10.2016
By NATALIE ANGIER The female bonobo apes of the Wamba forest in the Democratic Republic of Congo had just finished breakfast and were preparing for a brief nap in the treetops, bending and crisscrossing leafy branches into comfortable day beds. But one of the females was in estrus, her rump exceptionally pink and swollen, and four males in the group were too excited to sleep. They took turns wildly swinging and jumping around the fertile female and her bunkmates, shaking the branches, appearing to display their erections and perforating the air with high-pitched screams and hoots. Suddenly, three older, high-ranking female bonobos bolted up from below, a furious blur of black fur and swinging limbs and, together with the female in estrus, flew straight for the offending males. The males scattered. The females pursued them. Tree boughs bounced and cracked. Screams on all sides grew deafening. Three of the males escaped, but the females cornered and grabbed the fourth one — the resident alpha male. He was healthy, muscular and about 18 pounds heavier than any of his captors. But no matter. The females bit into him as he howled and struggled to pull free. Finally, “he dropped from the tree and ran away, and he didn’t appear again for about three weeks,” said Nahoko Tokuyama, of the Primate Research Institute at Kyoto University in Japan, who witnessed the encounter. When the male returned, he kept to himself. Dr. Tokuyama noticed that the tip of one of his toes was gone. “Being hated by females,” she said in an email interview, “is a big matter for male bonobos.” The toe-trimming incident was extreme but not unique. Describing results from their long-term field work in the September issue of Animal Behaviour, Dr. Tokuyama and her colleague Takeshi Furuichi reported that the female bonobos of Wamba often banded together to fend off male aggression, and in patterns that defied the standard primate rule book. © 2016 The New York Times Company
Keyword: Aggression; Sexual Behavior
Link ID: 22641 - Posted: 09.10.2016
By Karen Zusi At least one type of social learning, or the ability to learn from observing others’ actions, is processed by individual neurons within a region of the human brain called the rostral anterior cingulate cortex (rACC), according to a study published today (September 6) in Nature Communications. The work is the first direct analysis in humans of the neuronal activity that encodes information about others’ behavior. “The idea [is] that there could be an area that’s specialized for processing things about other people,” says Matthew Apps, a neuroscientist at the University of Oxford who was not involved with the study. “How we think about other people might use distinct processes from how we might think about ourselves.” During the social learning experiments, the University of California, Los Angeles (UCLA) and CalTech–based research team recorded the activity of individual neurons in the brains of epilepsy patients. The patients were undergoing a weeks-long procedure at the Ronald Reagan UCLA Medical Center in which their brains were implanted with electrodes to locate the origin of their epileptic seizures. Access to this patient population was key to the study. “It’s a very rare dataset,” says Apps. “It really does add a lot to the story.” With data streaming out of the patients’ brains, the researchers taught the subjects to play a card game on a laptop. Each turn, the patients could select from one of two decks of face-down cards: the cards either gave $10 or $100 in virtual winnings, or subtracted $10 or $100. In one deck, 70 percent of the cards were winning cards, while in the other only 30 percent were. The goal was to rack up the most money. © 1986-2016 The Scientist
Keyword: Learning & Memory; Attention
Link ID: 22640 - Posted: 09.10.2016
By Jessica Hamzelou As any weight-watcher knows, carb cravings can be hard to resist. Now there’s evidence that carbohydrate-rich foods may elicit a unique taste too, suggesting that “starchy” could be a flavour in its own right. It has long been thought that our tongues register a small number of primary tastes: salty, sweet, sour and bitter. Umami – the savoury taste often associated with monosodium glutamate – was added to this list seven years ago, but there’s been no change since then. However, this list misses a major component of our diets, says Juyun Lim at Oregon State University in Corvallis. “Every culture has a major source of complex carbohydrate. The idea that we can’t taste what we’re eating doesn’t make sense,” she says. Complex carbohydrates such as starch are made of chains of sugar molecules and are an important source of energy in our diets. However, food scientists have tended to ignore the idea that we might be able to specifically taste them, says Lim. Because enzymes in our saliva break starch down into shorter chains and simple sugars, many have assumed we detect starch by tasting these sweet molecules. Her team tested this by giving a range of different carbohydrate solutions to volunteers – who it turned out were able to detect a starch-like taste in solutions that contained long or shorter carbohydrate chains. “They called the taste ‘starchy’,” says Lim. “Asians would say it was rice-like, while Caucasians described it as bread-like or pasta-like. It’s like eating flour.” © Copyright Reed Business Information Ltd.
Keyword: Chemical Senses (Smell & Taste); Obesity
Link ID: 22639 - Posted: 09.10.2016
By Abby Olena Mammalian prions are notoriously difficult as structural biology subjects, given their insolubility and tendency to aggregate. Researchers have now overcome these challenges to figure out the preliminary structure of a shortened form of infectious prion (PrPSc), which they report today (September 8) in PLOS Pathogens. “For the first time, we have a structure of an infectious mammalian prion,” said Giuseppe Legname of Scuola Internazionale Superiore di Studi Avanzati in Trieste, Italy, who was not involved in this study. “It’s a very important paper,” he added. “What we have done is to obtain a very simple, very preliminary idea of what the structure of these mammalian prions are,” said study coauthor Jesús Requena of the University of Santiago de Compostela in Spain. Requena and colleagues generated a shortened form of PrPSc by injecting a laboratory strain of prions into transgenic mice that express a truncated form of normal cellular prion protein (PrPC), which lacks the attachment of a membrane anchor present in full-length PrPSc. In nature, PrPC transforms into full-length PrPSc, which causes Creutzfeldt-Jakob disease in humans, scrapie in sheep, and mad cow disease. The absence of the membrane anchor in shortened PrPSc from the transgenic mice allowed the researchers to isolate a fairly homogeneous population of PrPSc. They confirmed that this population was infectious by inoculating wild-type mice, which then developed symptoms of prion disease. © 1986-2016 The Scientist
Keyword: Prions
Link ID: 22638 - Posted: 09.10.2016
By JACK HEALY CINCINNATI — On the day he almost died, John Hatmaker bought a packet of Oreos and some ruby-red Swedish Fish at the corner store for his 5-year-old son. He was walking home when he spotted a man who used to sell him heroin. Mr. Hatmaker, 29, had overdosed seven times in the four years he had been addicted to pain pills and heroin. But he hoped he was past all that. He had planned to spend that Saturday afternoon, Aug. 27, showing his son the motorcycles and enjoying the music at a prayer rally for Hope Over Heroin in this region stricken by soaring rates of drug overdoses and opioid deaths. But first, he decided as he palmed a sample folded into a square of paper, he would snort this. As he crumpled to the sidewalk, Mr. Hatmaker became one of more than 200 people to overdose in the Cincinnati area in the past two weeks, leaving three people dead in what the officials here called an unprecedented spike. Similar increases in overdoses have rippled recently through Indiana, Kentucky and West Virginia, overwhelming ambulance crews and emergency rooms and stunning some antidrug advocates. Addiction specialists said the sharp increases in overdoses were a grim symptom of America’s heroin epidemic, and of the growing prevalence of powerful synthetic opiates like fentanyl. The synthetics are often mixed into batches of heroin, or sprinkled into mixtures of caffeine, antihistamines and other fillers. In Cincinnati, some medical and law enforcement officials said they believed the overdoses were largely caused by a synthetic drug called carfentanil, an animal tranquilizer used on livestock and elephants with no practical uses for humans. Fentanyl can be 50 times stronger than heroin, and carfentanil is as much as 100 times more potent than fentanyl. Experts said an amount smaller than a snowflake could kill a person. © 2016 The New York Times Company
Keyword: Drug Abuse; Pain & Touch
Link ID: 22637 - Posted: 09.07.2016
By Helen Thomson High levels of inflammation as a child may predict a higher risk of manic behaviour in later life, a finding that could lead to new ways of treating conditions like bipolar disorder. Hypomania involves spells of hyperactivity and is often a symptom of mood disorders, including bipolar disorder, seasonal affective disorder and some kinds of psychosis. People experiencing hypomania may take more risks, feel more confident and become impatient with others. After spells like this, they may “crash”, needing to sleep for long periods and sometimes remembering little about the previous few days. Earlier studies suggested a link between inflammation and mood disorders, prompting Joseph Hayes at University College London and his team to see if inflammation as a child might lead to mental health problems later. Analysing data from more than 1700 people, his team identified a significant link between high levels of a chemical involved in inflammation at age 9, and experiencing aspects of hypomania at age 22. The chemical, called IL-6, is normally secreted by white blood cells to stimulate an inflammatory immune response to infection or trauma. Hayes’s team says it is unclear how inflammation in childhood could induce symptoms of hypomania but IL-6 is known to affect the brain. A study that used injections to increase IL-6 in the blood of healthy volunteers found that this caused symptoms of anxiety, and reduced performance in memory tests. © Copyright Reed Business Information Ltd.
Keyword: Schizophrenia
Link ID: 22636 - Posted: 09.07.2016
Hannah Devlin Science correspondent Babies born by caesarean section are more likely to be obese as adults, according to a study that suggests the way we are born could have a lasting impact on health. Birth by caesarean was linked to a 15% higher risk of obesity in children compared with vaginal birth. The scientists involved believe that babies born by caesarean miss out on exposure to bacteria in the birth canal that colonise the baby’s gut and may ultimately change the body’s metabolic rate - and even how hungry we feel. Audrey Gaskins, an epidemiologist at Harvard University and co-author of the new study, said: “Children born via C-section harbour less diverse gut bacteria and these patterns of less diversity have been linked to increased capacity for energy harvest by the gut microbiota. You can think of it as a slower metabolism.” Previous studies have found the same link, but were less able to rule out other factors, such as the mother’s weight or health. The latest research, which included 22,068 children born to 15,271 women, suggests that the link is not simply explained by overweight women or those with pregnancy complications such as high blood pressure being more likely to deliver by caesarean. The link remained after maternal weight was taken into account, and was more striking when siblings who had different types of births were compared. Within families, children born by caesarean were 64% more likely to be obese than their siblings born by vaginal delivery. “With siblings, they have the same mother and home environment so the genetics, the feeding environment, are all controlled for,” said Dr Gaskins. © 2016 Guardian News and Media Limited
Keyword: Obesity; Development of the Brain
Link ID: 22635 - Posted: 09.07.2016
By JANE E. BRODY As a woman of a certain age who consumes a well-balanced diet of all the usual food groups, including reasonable amounts of animal protein, I tend to dismiss advice to take a multivitamin supplement. I’ve been told repeatedly by nutrition experts that the overuse of dietary supplements for “nutritional insurance” has given Americans the most expensive urine in the world. I do take a daily supplement of vitamin D, based on considerable evidence of its multiple health benefits, especially for older people. However, based on advice from the National Academy of Medicine and an examination of accumulating research, I’m prompted to consider also taking a vitamin B12 supplement in hopes of protecting my aging brain. Animal protein foods — meat, fish, milk, cheese and eggs — are the only reliable natural dietary sources of B12, and I do get ample amounts of several in my regular diet. But now at age 75, I wonder whether I’m still able to reap the full benefit of what I ingest. You see, the ability to absorb B12 naturally present in foods depends on the presence of adequate stomach acid, the enzyme pepsin and a gastric protein called intrinsic factor to release the vitamin from the food protein it is attached to. Only then can the vitamin be absorbed by the small intestine. As people age, acid-producing cells in the stomach may gradually cease to function, a condition called atrophic gastritis. A century ago, researchers discovered that some people — most likely including Mary Todd Lincoln — had a condition called pernicious anemia, a deficiency of red blood cells ultimately identified as an autoimmune disease that causes a loss of stomach cells needed for B12 absorption. Mrs. Lincoln was known to behave erratically and was ultimately committed to a mental hospital. © 2016 The New York Times Company
Keyword: Development of the Brain
Link ID: 22634 - Posted: 09.06.2016
Chris Chambers One of the most compelling impressions in everyday life is that wherever we look, we “see” everything that is happening in front of us – much like a camera. But this impression is deceiving. In reality our senses are bombarded by continual waves of stimuli, triggering an avalanche of sensations that far exceed the brain’s capacity. To make sense of the world, the brain needs to determine which sensations are the most important for our current goals, focusing resources on the ones that matter and throwing away the rest. These computations are astonishingly complex, and what makes attention even more remarkable is just how effortless it is. The mammalian attention system is perhaps the most efficient and precisely tuned junk filter we know of, refined through millions of years of annoying siblings (and some evolution). Attention is amazing but no system is ever perfect. Our brain’s computational reserves are large but not infinite, and under the right conditions we can “break it” and peek behind the curtain. This isn’t just a fun trick – understanding these limits can yield important insights into psychology and neurobiology, helping us to diagnose and treat impairments that follow brain injury and disease. Thanks to over a hundred years of psychology research, it’s relatively easy to reveal attention in action. One way is through the phenomenon of change blindness. Try it yourself by following the instructions in the short video below (no sound). When we think of the term “blindness” we tend to assume a loss of vision caused by damage to the eye or optic nerves. But as you saw in the video, change blindness is completely normal and is caused by maxing out your attentional capacity. © 2016 Guardian News and Media Limited
Keyword: Attention; Vision
Link ID: 22633 - Posted: 09.06.2016
By Clare Wilson Traffic fumes go to your head. Tiny specks of metal in exhaust gases seem to fly up our noses and travel into our brains, where they may contribute to Alzheimer’s disease. Iron nanoparticles were already known to be present in the brain – but they were thought to come from the iron naturally found in our bodies, derived from food. Now a closer look at their structure suggests the particles mostly come from air pollution sources, like traffic fumes and coal burning. The findings are a smoking gun, says Barbara Maher of Lancaster University in the UK. Iron is present harmlessly in our bodies in different forms, as it is part of many biological molecules. But the form known as magnetite, or iron oxide, which is highly reactive and magnetic, has been implicated in Alzheimer’s disease. Maher’s team looked at the brains of 37 people who had lived either in Manchester in the UK or Mexico City. All contained millions of magnetite particles per gram of brain tissue, detected by measuring how magnetic the brain tissue was. The surprise came when the team used electron microscopes to take a close look at particles in the front part of the brains of six people. Round particles of magnetite outnumbered angular magnetite crystals by about one hundred to one. Crystal forms are more likely to have a natural source – such as iron that has come out of the body’s cells. But round particles normally come from melting iron at high temperatures, which happens when fuel is burned. © Copyright Reed Business Information Ltd.
Keyword: Neurotoxins
Link ID: 22632 - Posted: 09.06.2016
Susan Milius Contrary to many adorable children’s stories, hibernation is so not sleeping. And most animals can’t do both at the same time. So what’s with Madagascar’s dwarf lemurs? The fat-tailed dwarf lemur slows its metabolism into true hibernation, and stays there even when brain monitoring shows it’s also sleeping. But two lemur cousins, scientists have just learned, don’t multitask. Like other animals, they have to rev their metabolisms out of hibernation if they want a nap. Hibernating animals, in the strictest sense, stop regulating body temperature, says Peter Klopfer, cofounder of the Duke Lemur Center in Durham, N.C. “They become totally cold-blooded, like snakes.” By this definition, bears don’t hibernate; they downregulate, dropping their body temperatures only modestly, even when winter den temperatures sink lower. And real hibernation lasts months, disqualifying short-termers such as subtropical hummingbirds. The darting fliers cease temperature regulation and go truly torpid at night. “You can pick them out of the trees,” Klopfer says. The fat-tailed dwarf lemur, Cheirogaleus medius, was the first primate hibernator discovered, snuggling deep into the softly rotting wood of dead trees. “You’d think they’d suffocate,” he says. But their oxygen demands plunge to somewhere around 1 percent of usual. As trees warm during the day and cool at night, so do these lemurs. When both a tree and its inner lemur heat up, the lemur’s brain activity reflects mammalian REM sleep. |© Society for Science & the Public 2000 - 2016
Keyword: Sleep; Evolution
Link ID: 22631 - Posted: 09.06.2016
By Andy Coghlan Antidepressants may be bad for your bones. People who take some selective serotonin reuptake inhibitors (SSRI) have been found to have a higher risk of fractures, but it wasn’t clear whether this was due to the drug or their depression. “It’s a puzzling question,” says Patricia Ducy at Columbia University, New York. But her team have now found that giving mice fluoxetine – the active ingredient in Prozac – for six weeks causes them to lose bone mass. The team identified a two-stage process by measuring bones, blood and gene activity. During the first three weeks, bones grew stronger as the fluoxetine impaired osteoclasts, cells that usually deplete bone tissue. But by six weeks, the higher levels of serotonin prompted by the drug disrupted the ability of the hypothalamus region of the brain to promote bone growth. “We see bone gain, but it’s not long-lasting, and is rapidly overwhelmed by the negative effects,” says Ducy. She says this two-phase pattern is also seen in people. In the short term, those who take fluoxetine are less likely to break a bone, but the risk of bone depletion and fractures rises when they have been taking the drug for a year or more. © Copyright Reed Business Information Ltd.
Keyword: Depression
Link ID: 22630 - Posted: 09.06.2016
By The Scientist Staff Growing up, we learn that there are five senses: sight, smell, touch, taste, and hearing. For the past five years, The Scientist has taken deep dives into each of those senses, explorations that revealed diverse mechanisms of perception and the impressive range of these senses in humans and diverse other animals. But as any biologist knows, there are more than just five senses, and it’s difficult to put a number on how many others there are. Humans’ vestibular sense, for example, detects gravity and balance through special organs in the bony labyrinth of the inner ear. Receptors in our muscles and joints inform our sense of body position. (See “Proprioception: The Sense Within.”) And around the animal kingdom, numerous other sense organs aid the perception of their worlds. The comb jelly’s single statocyst sits at the animal’s uppermost tip, under a transparent dome of fused cilia. A mass of cells called lithocytes, each containing a large, membrane-bound concretion of minerals, forms a statolith, which sits atop four columns called balancers, each made up of 150–200 sensory cilia. As the organism tilts, the statolith falls towards the Earth’s core, bending the balancers. Each balancer is linked to two rows of the ctenophore’s eight comb plates, from which extend hundreds of thousands of cilia that beat together as a unit to propel the animal. As the balancers bend, they adjust the frequency of ciliary beating in their associated comb plates. “They’re the pacemakers for the beating of the locomotor cilia,” says Sidney Tamm, a researcher at the Marine Biological Laboratory in Woods Hole, Massachusetts, who has detailed the structure and function of the ctenophore statocyst (Biol Bull, 227:7-18, 2014; Biol Bull, 229:173-84, 2015). © 1986-2016 The Scientist
Keyword: Pain & Touch; Chemical Senses (Smell & Taste)
Link ID: 22629 - Posted: 09.05.2016
By Jesse Singal Back in 2014, a bigoted African leader put J. Michael Bailey, a psychologist at Northwestern, in a strange position. Yoweri Museveni, the president of Uganda, had been issuing a series of anti-gay tirades, and — partially fueled by anti-gay religious figures from the U.S. — was considering toughening Uganda’s anti-gay laws. The rhetoric was getting out of control: “The commercialisation of homosexuality is unacceptable,” said Simon Lokodo, Uganda’s ethics minister. “If they were doing it in their own rooms we wouldn’t mind, but when they go for children, that’s not fair. They are beasts of the forest.” Eventually, Museveni said he would table the idea of new legislation until he better understood the science of homosexuality, and agreed to lay off Uganda’s LGBT population if someone could prove to him homosexuality was innate. That’s where Bailey comes in: He’s a leading sex researcher who has published at length on the question of where sexual orientation comes from. LGBT advocates began reaching out to him to explain the science of homosexuality and, presumably, denounce Museveni for his hateful rhetoric. But “I had issues with rushing out a scientific statement that homosexuality is innate,” he said in an email, because he’s not sure that’s quite accurate. While he did write articles, such as an editorial in New Scientist, explaining why he thought Museveni’s position didn’t make sense, he stopped short of calling homosexuality innate. He also realized that in light of some recent advances in the science of sexual orientation, it was time to publish an article summing up the current state of the field — gathering together all that was broadly agreed-upon about the nature and potential origins of sexual orientation. (In the meantime, Museveni did end up signing the anti-gay legislation, justifying his decision by reasoning that homosexuality “was learned and could be unlearned.”) © 2016, New York Media LLC.
Keyword: Sexual Behavior; Development of the Brain
Link ID: 22628 - Posted: 09.05.2016
A new study by investigators at Brigham and Women's Hospital in collaboration with researchers at the University of York and Leeds in the UK and MD Andersen Cancer Center in Texas puts to the test anecdotes about experienced radiologists' ability to sense when a mammogram is abnormal. In a paper published August 29 in the Proceedings of the National Academy of Sciences, visual attention researchers showed radiologists mammograms for half a second and found that they could identify abnormal mammograms at better than chance levels. They further tested this ability through a series of experiments to explore what signal may alert radiologists to the presence of a possible abnormality, in the hopes of using these insights to improve breast cancer screening and early detection. "Radiologists can have 'hunches' after a first look at a mammogram. We found that these hunches are based on something real in the images. It's really striking that in the blink of an eye, an expert can pick up on something about that mammogram that indicates abnormality," said Jeremy Wolfe, PhD, senior author of the study and director of the Visual Attention Laboratory at BWH. "Not only that, but they can detect something abnormal in the other breast, the breast that does not contain a lesion." In the clinic, radiologists carefully evaluate mammograms and may use computer automated systems to help screen the images. Although they would never assess an image in half a second in the clinic, the ability of experts to extract the "gist" of an image quickly suggests that there may be a detectable signs of breast cancer that radiologists are rapidly picking up. Copyright 2016 ScienceDaily
Keyword: Attention; Vision
Link ID: 22627 - Posted: 09.05.2016
By Alison F. Takemura A stationary Carolina sphinx moth (Manduca sexta) is the Cinderella of the animal kingdom. The hummingbird-size insect has dull, dark wings that are mottled like charred wood, and a plump body reminiscent of a small breakfast sausage. Casual observers of M. sexta often see little else. “They say, ‘Oh, it doesn’t look so nice. It’s just grey.’ But as soon as [the moths] start flying, they’re completely impressed,” says Danny Kessler, a pollination ecologist at the Max Planck Institute of Chemical Ecology in Germany. “They change their minds completely.” Hawkmoths, the group to which M. sexta belongs, whir their wings like hummingbirds as they flit between flowers, hovering to drink nectar. M. sexta’s proboscis, longer than its 2-inch body, stays unfurled, a straw ready to sip. Kessler studies the interaction between the Carolina sphinx moth, whose larvae are known as tobacco hornworms, and its preferred food source, the coyote tobacco plant (Nicotiana attenuata), to better understand how insect behavior affects a plant’s reproductive success. M. sexta adults drink nectar from tobacco’s skinny, white, trumpet-shape flowers, foraging from them at night and pollinating them in the process. Scientists have known for decades that the moth uses its antennae to detect the flowers’ scent—even from several miles away, Kessler says. © 1986-2016 The Scientist
Keyword: Chemical Senses (Smell & Taste)
Link ID: 22626 - Posted: 09.05.2016


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