Fingerprints are for more than a good grip; they also allow fingers to feel fine textures, according to a new study. As fingers move across a surface, the intricate geography of the finger tips, known as epidermal ridges, help select and amplify just the right vibrations to convey information from the skin to the brain. Neuroscientist Ellen Lumkin compares the ridges on fingers to the cochlea in the ear. “Like the cochlea is a frequency analyzer for sounds, the fingertips are frequency analyzers for fingers,” says Lumpkin [Science News] Fingerprints help filter out the tactile equivalent of white noise.
When a finger sweeps over a finely textured surface, such as a cotton sleeve or a wooden coffee table, the interaction sends a large range of vibrations into the skin. Specialized sensors called Pacinian fibers, the tips of nerve fibers, detect only a select few of the vibrations — those right around 250 hertz — before sending the signal to the brain, where the touch sensation is processed [Science News]. But since Pacinian fibers are located relatively deep—about 2 millimeters—under the skin, researchers guessed that fingerprints help magnify the vibrations.
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A new study has found higher than expected levels of a controversial plastics chemical in people who had fasted for 24 hours. This surprised researchers because the chemical, bisphenol A (BPA), was thought to be ingested when trace amounts leaked from plastic food containers and bottles, and researchers thought it quickly passed through the system.
The finding suggests that exposure to BPA may come from many different sources, not just food products, or that the body doesn’t metabolize the chemical as fast as has been thought, the researchers said…. “What this study shows is that either we are getting exposed to a lot more BPA than we thought, or it’s hanging around longer than we thought, or both,” said lead researcher Dr. Richard W. Stahlhut [HealthDay News].
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Infusions of stem cells taken from multiple sclerosis patients’ own bone marrows have shown great promise in rolling back symptoms of the disease. In a small study, researchers found that 81 percent of the participants still showed some improvement three years after the treatment, and the rest of the patients had not deteriorated. “All therapies to date … have focused on slowing the progression of disease,” said [lead researcher] Richard Burt…. “What this actually did is that it reversed disability. This is the first time we have turned the tide on this disease” [Chicago Sun-Times].
In multiple sclerosis, or MS, the patients’ immune systems turn on their own central nervous systems, stripping the protective myelin sheaths from nerve fibers and leading to problems with vision, balance, and coordination. The researcher team tested the new treatment on 21 patients in the early stages of the disease, when symptoms alternately flare up and recede. Burt and his colleagues had previously tried using stem cells to reverse this process in patients with advanced stages of the disease, with little success. “If you wait until there’s neuro-degeneration, you’re trying to close the barn door after the horse has already escaped,” says Burt. What you really want to do is stop the autoimmune attack before it causes nerve-cell damage, he adds [New Scientist].
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A Florida couple has just received a genetic copy of their beloved and deceased golden Labrador Sir Lancelot, naming the three-month-old puppy Lancelot Encore. The couple paid $155,000 for one of the first commercially cloned dogs in the world, and say the money was well spent. “He was a wonderful dog,” said Nina Otto, 66. “Money wasn’t an object. We just wanted our wonderful, loving dog back” [ABC News]. The project was masterminded by the California biotech company BioArts.
Lancelot Encore joins a handful of other dogs cloned either commercially or as a proof of concept, and the latest success seems to indicate that researchers have thoroughly overcome the scientific barriers to cloning man’s best friend. Canines are considered one of the more difficult mammals to clone because of their reproductive cycle that includes difficult-to-predict ovulations [Reuters]. Now the fate of the fledging pet cloning industry is largely dependent on whether dog lovers think that clones are worth the high price tag. However, just yesterday another cloning company announced a new technique that could reduce the cost of dog cloning to about $50,000 within three years.
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Locusts are prompted to band together in enormous, destructive swarms by the same brain chemical that is linked to happiness in humans. A fascinating new study has found that locusts that are about to swarm experience a sudden surge of serotonin, the same neurotransmitter that’s targeted by antidepressant drugs. “Here we have a solitary and lonely creature, the desert locust. But just give them a little serotonin, and they go and join a gang,” observed Malcolm Burrows [AP], one of the study’s authors.
Researchers say the findings may lead to methods to block the formation of locust swarms. These infestations, which can cover hundreds of square miles and involve billions of vegetation-munching insects, can devastate agriculture and cost tens of millions of dollars to control [The New York Times].
Because locusts usually avoid each other, it’s only dire circumstances that bring them together in buzzing hordes. For instance, unpredictable desert rains cause vegetation blooms, which in turn makes locust populations skyrocket. But as the rains abate and fertile land shrivels up, locusts crowd together in the remaining green patches. Eventually, the swarm trigger goes off and the locusts take to the skies—”a strategy of desperation driven by hunger,” [National Geographic News], says coauthor Stephen Rogers. When they make that behavior shift they also change appearance dramatically, going from light green to dark brown.
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A chemical found in common household products and cosmetics has been linked to a decrease in fertility in women, according to a new study. Researchers examined more than 1,000 pregnant women and found that those exposed to higher levels of perfluorinated chemicals (PFCs) had experienced more difficulty getting pregnant. PFCs are used to make textiles and leather resistant to water, dirt or oil. They are also found in personal care products such as nail polish, dental floss or facial moisturizer. The chemicals resist breakdown and tend to persist in the environment and in the body for decades [Bloomberg]. “If this finding can be replicated, one would have to look for other chemicals to replace these,” [Washington Post] said lead researcher Jorn Olsen. Although experts caution that the correlation doesn’t prove causation, many manufacturers have already taken steps to cut back on PFCs.
Data for the study was taken from 1,240 women in the Danish Birth Cohort when they were six to 12 weeks pregnant. If they reported that it took them longer than 12 months to get pregnant or if they used drugs designed to increase their chances of conceiving, they were considered to have infertility. This is a generally accepted definition of infertility by experts in the field [ABC News]. The women were divided into four groups based on levels of two types of PFCs, perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), found in their blood. Compared to women in the group with the lowest levels of PFOS, women with higher levels took from 70 percent to 134 percent longer to conceive. For PFOA, women with higher levels took from 60 percent to 154 percent longer to conceive. The researchers accounted for factors such as age and economic and social factors, although they admit that they lacked information on other factors that could influence fertility such as timing and frequency of intercourse and sperm quality.
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Sunshades in the stratosphere to reflect sunlight away from our planet. Dumping iron into the oceans to encourage algae blooms that would take up carbon dioxide. Painting every rooftop white. These are just a few of the geoengineering schemes that have been suggested to artificially alter the planet’s climate and counteract global warming.
Now researchers have helpfully ranked 17 proposals on their possible efficacy, saying that it’s past time to take a hard look at the ambitious ideas. “There is a worrying feeling that we’re not going to get our act together fast enough,” says [coauthor Tim] Lenton, referring to international efforts to limit greenhouse gas emissions. Scientists have reached a “social tipping point” and are starting to wonder which techniques might complement emissions cuts, he says [New Scientist]. The study, published in Atmospheric Chemistry and Physics, didn’t include an analysis of costs and environmental impacts.
Lenton says there has been too much hype and not enough analysis regarding geoengineering schemes, so he decided to start by asking a straightforward question. At the most basic level, earth’s surface temperature is governed by a balance between incoming Solar radiation and outgoing terrestrial radiation [Physics World]. The researchers examined how each of the geoengineering schemes would sway that balance, either by reflecting away solar radiation or reducing carbon dioxide that traps heat in the atmosphere. They found that a few proposed technologies could have a planet-wide cooling impact, but say those would be extremely hard to pull off.
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Charles Darwin‘s theory of evolution may have been shaped by his abhorrence of slavery as much as by his keen observations of Galapagos finches, a new book argues. Darwin’s Sacred Cause, by Adrian Desmond and James Moore, notes that slavery propaganda of the time often claimed that different races belonged to different species, a notion that Darwin’s work obliterated. The book suggests that Darwin’s unique approach to evolution – relating all races and species by “common descent” – could have been fostered by his anti-slavery beliefs [BBC News]. Published to coincide with Darwin’s 200th birthday and the 150th anniversary of his publication of On the Origin of Species this year, the book is likely to stir up a new debate over Darwin’s motives.
Many members of Darwin’s extended family were deeply devoted to the abolitionist cause, including his grandfather, Josiah Wedgwood, who founded a chinaware company and produced cameos distributed by anti-slavery campaigners; the medallions bore the legend “Am I Not a Man and a Brother?” Darwin’s mother and wife were Wedgwoods and anti-slavery was what Darwin called a “sacred cause”. He was taught to see the oppressed black as a “brother”. This explains why, when he went to Edinburgh University at 16, he could apprentice himself to a freed Guyanese slave to learn the art of bird preservation without thinking it [beneath his dignity] [Times Online]. Darwin later described that former slave as one of his intimate friends.
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Just weeks after NASA celebrated the Spirit rover‘s fifth anniversary on Mars, the robotic explorer suffered a mysterious glitch that caused it to freeze in place for a day. The rover couldn’t tell NASA what had gone wrong or even what it did for that stretch of time, and it even lost track of the sun. “We don’t have a good explanation yet for the way Spirit has been acting for the past few days,” said JPL team leader Sharon Laubach. “Our next steps will be diagnostic activities” [BBC News].
The glitch came last Sunday, which marked Spirit’s 1,800th Martian day, or sol, on the planet. NASA sent the rover its driving directions for the day and Spirit acknowledged receiving them, but then it failed to move. More strangely, the Spirit had no memory of what it had done for that part of Sol 1800. The rover did not record actions, as it otherwise always does, to the part of its computer memory that retains information even when power is turned off, the so-called nonvolatile memory. “It’s almost as if the rover had a bout of amnesia,” said John Callas, the project manager for the rovers [The New York Times]. When NASA directed the rover on Monday to photograph the sun to establish its orientation, Spirit did so but reported that the sun was not in its “expected location.”
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For the first time, researchers have watched weather conditions shift on a planet outside our solar system, and say the temperature spikes are out of this world. Normally, the planet is a toasty 980 degrees [Fahrenheit] or so. But in the few hours it whips around its sun the planet gets zapped with mega-heat, pushing the thermometer closer to 2,240 degrees…. When it comes closest to its star, it becomes one giant “brewing storm” [AP].
The gas giant, known as HD 80606b, lies about 190 light-years away in the constellation Ursa Major, and has an extremely elliptical orbit. When it’s closest to its sun, it is barely more than 300,000 miles away – not much more distant than our cold moon is from us. But when the planet is farthest away from its sun and coolest, it’s nearly 70 million miles away. That would be like some object flying somewhere far out between the orbits of Earth and Venus [San Francisco Chronicle]. One complete orbit around its sun takes 111 days.
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Honeybees have the ability to distinguish and remember visual quantities up to four, according to a new study. Researchers demonstrated that honeybees can match patterns containing the same number of icons, even when the icons are of mixed color and shape. This suggests that honeybees possess a basic number sense that was once thought to be exclusive to vertebrates. Researcher Shaowu Zhang says, “There has been a lot of evidence that vertebrates, such as pigeons, dolphins or monkeys, have some numerical competence but we never expected to find such abilities in insects. So far as these very basic skills go, there is probably no boundary between insects, animals and us” [Daily Mail]
To test the extent of the bees’ number sense, researchers set up a Y-shaped maze with a sweet treat at the end of one arm. In the training phase, bees entered the base of the maze through an entrance marked with either two or three dots. They had to remember this number when the maze forked into two paths— one marked with two dots, the other with three—in order to reach a sugar-water reward [Telegraph]. The 20 or so bees that were trained attained a success rate of 70 percent. Researchers then presented tougher challenges by increasing the number of dots. The bees could also distinguish between three and four dots, but were confused when even more dots were added.
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One of the most controversial geoengineering schemes that has been proposed to slow the course of global warming, ocean fertilization, received mixed reviews from a new study. The idea involves dumping iron into the ocean to nourish plankton and spur enormous blooms, which would then die off and fall to the sea floor, bringing the carbon dioxide they’d absorbed with them. Now, researchers studying natural plankton blooms near Antarctica have new evidence to fuel the debate over the efficacy of the process, and whether or not it can get our planet out of hot water.
Scientists took measurements around the Crozet Islands, where there are naturally occurring fluxes in iron levels. To the north of the islands levels of iron are boosted each year as iron-rich volcanic rocks are eroded and the nutrients are carried off by the current [Times Online]. Researchers observed a huge plankton bloom there that covered an area the size of Ireland and lasted for more than two months, while also studying the water to the south of the islands, where the prevailing ocean currents don’t carry dissolved iron and therefore plankton blooms don’t form naturally. The results, to be published tomorrow in Nature [subscription required], showed that iron-enriched waters do, as hoped, encourage more carbon to be stored on the ocean floor. But the efficiency of artificial iron fertilisation could be as much as 50 times lower than previous estimates [New Scientist].
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A close examination of over 400 Triceratops skulls suggests that the iconic dinosaurs used their powerful horns to clash with rivals over mates, territory, and dominance. In a new study, researchers looked carefully for traces of scrapes and healed fractures on the fossilized skulls, and say the pattern they found fits the theory that the three-horned herbivores were going head-to-head. “The most likely culprit for all of the wounds on Triceratops frills was the horns of other Triceratops,” [lead researcher Andrew] Farke said. “Our findings provide some of the best evidence to date that Triceratops might have locked horns with each other, wrestling like modern antelope and deer” [Times Online].
The researchers compared the Triceratops skulls to those of another dinosaur called Centrosaurus, which also boasted three horns and a bony protective frill around its face. The two species were related, but Centrosaurus died out about 75 million years ago and had its largest horn on its snout, while Triceratops lasted until 65 million years ago and had more prominent horns over its eyes. With such different horn patterns, the researchers assumed that if the dinosaurs were horn-butting with members of their own species the injuries of Triceratops and Centrosaurus should also be different from each other. But if they weren’t poking and butting one another with those horns, the injuries should be relatively similar, perhaps due to random nicks from clumsily running into a tree or head butts from predators, Farke said [LiveScience].
As the researchers report in the journal PLoS ONE, the Triceratops skulls showed a pattern of old injuries in one specific part of the bony frill that would likely have been impacted if two individuals were banging their heads together, but the Centrosaurus showed no such pattern.
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The regular collisions and concussions that take place on the football field may have a cumulative effect on the players’ brains, according to several new studies. In one small study, researchers found that just a few concussions can have an impact on cognitive skills 30 years later, while the other, more dramatic study found that a deceased NFL player was suffering from a severe degenerative brain disease. Taken together, the studies add to the mounting evidence that repeated blows to the head in football games lead to debilitating later-life afflictions such as dementia [Washington Post].
The biopsy of the NFL lineman Tom McHale, who played from 1987 to 1995 and who died last May at the age of 45, was announced at a press conference timed to coincide with the preparations for the Super Bowl this Sunday. The biopsy showed that McHale was suffering from chronic traumatic encephalopathy, researchers said. Known as C.T.E., the progressive condition results from repetitive head trauma and can bring on dementia in people in their 40s or 50s. Using techniques that can be administered only after a patient has died, doctors have identified C.T.E. in all six N.F.L. veterans between ages 36 and 50 who have been tested for the condition, further evidence of the dangers of improperly treated brain trauma in football [The New York Times].
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Trying to assess the importance of particular scientific papers has long been a tricky task. The current system relies on counting the number of times a paper is cited by others to determine how large an effect it has had on subsequent research, but this number can be misleading, a new study notes. Simply counting citations favors disciplines such as biology, where papers tend to be cited more, over fields such as mathematics, where citations are less frequent. In addition, a citation from a relatively marginal paper counts just the same as a citation from a leading researcher publishing in a marquee journal [Scientific American].
To try to get around these problems, a pair of researchers decided on a different tactic: They took the algorithm that Google uses to determine how to rank the Web pages turned up in a search result, and used it to rank the importance of scientific articles. The Google PageRank algorithm checks the number of times each Web page is linked to in order to determine its importance, which is equivalent to counting citations. But it has several other aspects that were very useful when applied to ranking scientific papers. The algorithm gives greater weight to citations from papers that list only a few references, and also to citations from papers that are themselves often cited. “Because of these attributes, PageRank readily identifies a large number of scientific ‘gems’–modestly cited articles that contain ground-breaking results” [arXiv], the researchers write. Among those gems turned up in the researchers first experiment were nine papers written by future Nobel Prize winners.
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