Domain: pnas.org
Stories and comments across the archive that link to pnas.org.
Stories · 206
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The Brains of Men and Women Aren't Really That Different, Study Finds (sciencemag.org)
sciencehabit writes: In the mid-19th century, researchers claimed they could tell the sex of an individual just by looking at their disembodied brain. But a new study (abstract) finds that human brains do not fit neatly into "male" and "female" categories. Indeed, all of our brains seem to share a patchwork of forms; some that are more common in males, others that are more common in females, and some that are common to both. The findings could change how scientists study the brain and even how society defines gender. -
Paternal Stress Is Passed To Offspring (arstechnica.com)
An anonymous reader writes: Researchers have discovered that stress experienced by male mice can be passed on to their offspring. "In earlier work, these scientists exposed male mice to six weeks of alternating stressors like 36 hours of constant light, a 15-minute exposure to fox odor, exposure to a novel object (marbles) overnight, 15 minutes of restraint in a 50 mL conical tube, multiple cage changes, white noise all night long, or saturated bedding.
Then the scientists allowed the mice to breed (abstract). Adult offspring of these chronically stressed dads had reduced hypothalamic-pituitary-adrenal stress axis reactivity; when they themselves were restrained for 15 minutes, they did not make as much corticosterone as mice sired by relaxed dads. This is relevant, and problematic, because blunted stress responses in humans are associated with neuropsychiatric disorders like depression, schizophrenia, and autism." -
Nearly Every Seabird May Be Eating Plastic By 2050
sciencehabit writes: According to a new study almost every ocean-foraging species of birds may be eating plastic by 2050. In the five large ocean areas known as "garbage patches," each square kilometer of surface water holds almost 600,000 pieces of debris. Sciencemag reports: "By 2050, about 99.8% of the species studied will have eaten plastic, the researchers report online today in the Proceedings of the National Academy of Sciences. Consuming plastic can cause myriad problems, Wilcox says. For example, some types of plastics absorb and concentrate environmental pollutants, he notes. After ingestion, those chemicals can be released into the birds’ digestive tracts, along with chemicals in the plastics that keep them soft and pliable. But plastic bits aren’t always pliable enough to get through a gull’s gut. Most birds have trouble passing large bits of plastic, and they build up in the stomach, sometimes taking up so much room that the birds can’t consume enough food to stay healthy." -
Internet Search Engines May Be Influencing Elections
sciencehabit writes: Thomas Epstein, a research psychologist at the American Institute for Behavioral Research in Vista, California, has found that the higher a politician ranks on a page of Internet search results, the more likely you are to vote for them — 80% more likely in some cases. The story also suggests that the folks at Google may already be influencing elections. "Google's algorithm has been determining the outcome of close elections around the world," says Epstein. As predicted, subjects spent far more time reading Web pages near the top of the list (abstract). But what surprised researchers was the difference those rankings made: Biased search results increased the number of undecided voters choosing the favored candidate by 48% compared with a control group that saw an equal mix of both candidates throughout the list. -
Scientists Show Human Aging Rates Vary Widely
HughPickens.com writes: Ever notice at your high school reunions how some classmates look ten years older than everybody else — and some look ten years younger. Now BBC reports that a study of people born within a year of each other has uncovered a huge gulf in the speed at which human bodies bodies age. The report tracked traits such as weight, kidney function and gum health and found that some of the 38-year-olds in the study were aging so badly that their "biological age" was on the cusp of retirement. "They look rough, they look lacking in vitality," says Prof Terrie Moffitt. The study says some people had almost stopped aging during the period of the study, while others were gaining nearly three years of biological age for every twelve months that passed. "Any area of life where we currently use chronological age is faulty, if we knew more about biological age we could be more fair and egalitarian," says Moffitt. The researchers studied aging in 954 young humans, the Dunedin Study birth cohort, tracking multiple biomarkers across three time points spanning their third and fourth decades of life. They developed and validated two methods by which aging can be measured in young adults, one cross-sectional and one longitudinal. According to Moffit the science of healthspan extension may be focused on the wrong end of the lifespan; rather than only studying old humans, geroscience should also study the young. "Eventually if we really want to slow the process of ageing to prevent the onset of disease we're going to have to intervene with young people." -
'Prisonized' Neighborhoods Make Recidivism More Likely
sciencehabit writes: One of the most important questions relating to incarceration and rehabilitation is how to discourage recidivism. After a prison stint, about half of convicts wind up back in the slammer within three years. But sociologist David Kirk noticed a pattern: convicts who moved away from their old neighborhood when released from prison had a much smaller recidivism rate. Kirk found that the concentration of former prisoners in a neighborhood had a dramatic effect on the likelihood of committing another offense (abstract). "So if an ex-con’s average chance of returning to prison after just 1 year was 22%—as it was in 2006—an additional new parolee in the neighborhood boosted that chance to nearly 25%. The numbers climb for each new parolee added. In some of the most affected neighborhoods—where five of every thousand residents were recent parolees—nearly 35% were back behind bars within a year of getting out." The rates stayed consistent even when controlling for chronic poverty and other neighborhood characteristics. -
The World's Most Wasteful Megacity
merbs writes: The world's most wasteful megacity is a densely populated, steadily aging, consumerist utopia where we buy, and throw away, a staggering amount of stuff (abstract). Where some faucet, toilet, or pipe, is constantly leaking in our apartments. Where an armada of commerce-beckoning lights are always on. Where a fleet of gas-guzzling cars still clog the roadways. I, along with my twenty million or so neighbors, help New York City use more energy, suck down more water, and spew out more solid waste than any other mega-metropolitan area. -
Recent Paper Shows Fracking Chemicals In Drinking Water, Industry Attacks It
eldavojohn writes: A recent paper published in the Proceedings of the National Academy of Sciences turned up 2-Butoxyethanol from samples collected from three households in Pennsylvania. The paper's level headed conclusion is that more conservative well construction techniques should be used to avoid this in the future and that flowback should be better controlled. Rob Jackson, another scientist who reviewed the paper, stressed that the findings were an exception to normal operations. Despite that, the results angered the PR gods of the Marcellus Shale Gas industry and awoke beltway insider mouthpieces to attack the research — after all, what are they paying them for? -
3.46-Billion-Year-Old 'Fossils' Were Not Created By Life Forms
sciencehabit writes: What are the oldest fossils on Earth? For a long time, a 3.46-billion-year-old rock from Western Australia seemed to hold the record. A 1993 Science paper (abstract) suggested that the Apex chert contained tiny, wormy structures that could have been fossilized cell walls of some of the world's first cyanobacteria. But now there is more evidence that these structures have nothing to do with life. The elongated filaments were instead created by minerals forming in hydrothermal systems, researchers report (abstract). After the minerals were formed, carbon glommed on to the edges, leaving behind an organic signature that looked suspiciously like cell walls. -
Cornell Study: For STEM Tenure Track, Women Twice As Likely To Be Hired As Men
_Sharp'r_ writes In the first "empirical study of sexism in faculty hiring using actual faculty members", Cornell University researchers found that when using identical qualifications, but changing the sex of the applicant, "women candidates are favored 2 to 1 over men for tenure-track positions in the science, technology, engineering and math fields." An anonymous reader links to the study itself. -
Jupiter Destroyed 'Super-Earths' In Our Early Solar System
sciencehabit writes: If Jupiter and Saturn hadn't formed where they did—and at the sizes they did—as the disk of dust and gas around our sun coalesced, then our solar system would be a very different and possibly more hostile place, new research suggests (abstract). Computer models reveal that in the solar system's first 3 million years or so, gravitational interactions with Jupiter, Saturn, and the gas in the protoplanetary disk would have driven super-Earth–sized planets closer to the sun and into increasingly elliptical orbits. In such paths, a cascade of collisions would have blasted any orbs present there into ever smaller bits, which in turn would have been slowed by the interplanetary equivalent of atmospheric drag and eventually plunged into the sun. As Jupiter retreated from its closest approach to the sun, it left behind the mostly rocky remnants that later coalesced into our solar system's inner planets, including Earth. -
$56,000 Speeding Ticket Issued Under Finland's System of Fines Based On Income
HughPickens.com writes Joe Pinsker writes at The Atlantic that Finish businessman Reima Kuisla was recently caught going 65 miles per hour in a 50 zone in his home country and ended up paying a fine of $56,000. The fine was so extreme because in Finland, some traffic fines, as well as fines for shoplifting and violating securities-exchange laws, are assessed based on earnings—and Kuisla's declared income was €6.5 million per year. Several years ago another executive was fined the equivalent of $103,000 for going 45 in a 30 zone on his motorcycle. Finland's system for calculating fines is relatively simple: It starts with an estimate of the amount of spending money a Finn has for one day, and then divides that by two—the resulting number is considered a reasonable amount of spending money to deprive the offender of. Then, based on the severity of the crime, the system has rules for how many days the offender must go without that money. Going about 15 mph over the speed limit gets you a multiplier of 12 days, and going 25 mph over carries a 22-day multiplier. Sweden, Denmark, Germany, Austria, France, and Switzerland also have some sliding-scale fines, or "day-fines," in place, but in America, flat-rate fines are the norm. Since the late 80s, when day-fines were first seriously tested in the U.S., they have remained unusual and even exotic.
Should such a system be used in the United States? After all, wealthier people have been shown to drive more recklessly than those who make less money. For example Steve Jobs was known to park in handicapped spots and drive around without license plates. But more importantly, day-fines could introduce some fairness to a legal system that many have convincingly shown to be biased against the poor. Last week, the Department of Justice released a comprehensive report on how fines have been doled out in Ferguson, Missouri. "Ferguson's law enforcement practices are shaped by the City's focus on revenue rather than by public safety needs," it concluded. The first day-fine ever in the U.S. was given in 1988, and about 70 percent of Staten Island's fines in the following year were day-fines. A similar program was started in Milwaukee, and a few other cities implemented the day-fine idea and according to Judith Greene, who founded Justice Strategies, a nonprofit research organization, all of these initiatives were effective in making the justice system fairer for poor people. "When considering a proportion of their income,people are at least constantly risk-averse. This means that the worst that would happen is that the deterrent effect of fines would be the same across wealth or income levels," says Casey Mulligan. "We should start small—say, only speeding tickets—and see what happens." -
California's Hot, Dry Winters Tied To Climate Change
mdsolar sends word that hot dry winters may be the norm in the future for California. "Climate change is one of the most prominent public health issues currently on the CDC's radar. The organization's Climate and Health Program attempts to help state and city health departments to prepare for the health impacts of climate change, which can come in the form of things like temperature extremes, air pollution, allergens, and changes in disease patterns; they can also be felt indirectly through issues like food security. Since 2012, California has been in the midst of a record-setting drought, with extremely warm and dry conditions characterizing the last three years in that state. A new paper published in the Proceedings of the National Academy of Sciences concludes that warming caused by humans is responsible for the conditions that have led to this California drought. This study, published by scientists affiliated with the Department of Environmental Earth System Science and the Woods Institute for Environment at Stanford University, used historical statewide data for observed temperature, precipitation, and drought in California. The investigators used the Palmer Hydrological Drought Index (PHDI) and the Palmer Drought Severity Index (PDSI), collected by the National Climatic Data Center, as measures of the severity of wet/dry anomalies. They also used global climate model simulations from the Coupled Model Intercomparison Project (CMIP) to compare historical predictions for anthropogenic and non-anthropogenic historical climates." -
Giant Asian Gerbils May Have Caused the Black Death
Dave Knott writes: Rats, long believed to be the scourge that brought the Black Death to 14th-century Europe, may not be the disease-bearing scoundrels we thought they were. Scientists have shifted blame for the medieval pandemic responsible for millions of deaths to a new furry menace: giant gerbils from Asia. University of Oslo researchers, working with Swiss government scientists, say a "pulse" of bubonic plague strains arrived sporadically from Asia. They posit the Yersinia pestis bacterium was likely carried over the Silk Road via fleas on the giant gerbils during intermittent warm spells. The fleas could have then transmitted the disease to humans. The Black Death is believed to have killed up to 200 million people in Europe. Though very rare today, cases of the plague still arise in Africa, Asia, the Americas and parts of the former Soviet Union, with the World Health Organization reporting 783 cases worldwide in 2013, including 126 deaths. -
Scientists In China Predict Pentagonal Graphene
TechkNighT_1337 writes: Chinese scientists made calculations and predict that a new 2D allotrope of carbon based in a pentagonal form resembling a common pavement in the streets of Cairo can be synthesized. They call this new form penta-graphene. From the announcement in the Chemistry World, they say: "The team found that not only should a pentagon-containing version of graphene be fairly stable, it should also be stronger than conventional graphene and be able to withstand higher temperatures, up to 730C. It would also be a natural semiconductor, unlike conventional graphene, which is a highly efficient conductor and has to be chemically modified to turn it into a semiconductor." -
Converting Sunlight Into Liquid Fuel With a Bionic Leaf
hypnosec writes: Artificial leaf techology made waves the moment it was announced by Daniel Nocera back in 2011. His latest research, published in PNAS, involves gathering hydrogen from this artificial leaf, carbon dioxide from another source, and feeding it to Ralstonia eutropha bacteria to create liquid fuel. Once the materials are fed to the bacteria, "An enzyme takes the hydrogen back to protons and electrons, then combines them with carbon dioxide to replicate—making more cells. Next, ... new pathways in the bacterium are metabolically engineered to make isopropanol." Researchers say the same process could be used to make vitamins. -
Lowering the Cost of Biofuel Production
sciencehabit writes: 2014 was a banner year for making automotive fuel from nonfood crops, with a series of major new production plants opening in the United States. However, producing this so-called cellulosic ethanol remains considerably more expensive than gasoline. So researchers are always on the lookout for new ways to trim costs. Now they have a new lead: a microbe that can use abundant nitrogen gas as the fertilizer it needs to produce ethanol from plants. The discovery (abstract) is "a major commercial accomplishment for biofuel production," says microbiologist Steven Ricke. -
Deep-Sea Microorganism Hasn't Evolved For Over 2 Billion Years
sfcrazy writes: Evolution is a natural process — everything evolves over a period of time, depending on the environment. But now scientists have discovered an organism which hasn't evolved for over more than 2 billion years. That's almost the half of the life of the Earth. "The scientists examined sulfur bacteria (abstract), microorganisms that are too small to see with the unaided eye, that are 1.8 billion years old and were preserved in rocks from Western Australia’s coastal waters. Using cutting-edge technology, they found that the bacteria look the same as bacteria of the same region from 2.3 billion years ago — and that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria found in mud off of the coast of Chile." Scientists say the extreme stability of the environment around the organisms made further adaptations unnecessary. -
Using Facebook Data, Algorithm Predicts Personality Better Than Friends
sciencehabit writes: A new study of Facebook data shows that machines are now better at sussing out our true personalities than our friends. One of the standard methods for assessing personality is to analyze people's answers to a 100-item questionnaire with a statistical technique called factor analysis. There are five main factors that divide people by personality—openness, conscientiousness, extraversion, agreeableness, and neuroticism—which is why personality researchers call this test the Big Five. People can accurately predict how their friends will answer the Big Five questions. ... Compared with humans predicting their friends' personalities by filling out the Big Five questionnaire, the computer's prediction based on Facebook likes was almost 15% more accurate on average, the team reports online today in PNAS (abstract). Only people's spouses were better than the computer at judging personality. -
Super-Sensitive Motion Sensor Could Be Used To Hunt For Extraterrestrial Life
Zothecula writes: People often state that certain planets are too hot, cold or toxic to support life. The catch, however, is that those people are really just talking about life as we know it here on Earth. By that same token, when rovers exploring other planets seek out chemical signatures associated with life forms, they're only able to identify chemicals that we know to look for. That's why Swiss scientists from the EPFL research center have created a device that identifies microscopic life based on nanoscale movements instead of chemistry (abstract). -
Scientists Say the Future Looks Bleak For Our Bones
HughPickens.com writes Nicholas St. Fluer reports at The Atlantic that according to researchers, our convenient, sedentary way of life is making our bones weak foretelling a future with increasing fractures, breaks, and osteoporosis. For thousands of years, hunter-gatherers trekked on strenuous ventures for food with dense skeletons supporting their movements and a new study pinpoints the origin of weaker bones at the beginning of the Holocene epoch roughly 12,000 years ago, when humans began adopting agriculture. "Modern human skeletons have shifted quite recently towards lighter—more fragile, if you like—bodies. It started when we adopted agriculture. Our diets changed. Our levels of activity changed," says Habiba Chirchir. A second study attributes joint bone weakness to different levels of physical activity in ancient human societies, also related to hunting versus farming.
The team scanned circular cross-sections of seven bones in the upper and lower limb joints in chimpanzees, Bornean orangutans and baboons. They also scanned the same bones in modern and early modern humans as well as Neanderthals, Paranthropus robustus, Australopithecus africanus and other Australopithecines. They then measured the amount of white bone in the scans against the total area to find the trabecular bone density. Crunching the numbers confirmed their visual suspicions. Modern humans had 50 to 75 percent less dense trabecular bone than chimpanzees, and some hominins had bones that were twice as dense compared to those in modern humans. Both studies have implications for modern human health and the importance of physical activity to bone strength. "The lightly-built skeleton of modern humans has a direct and important impact on bone strength and stiffness," says Tim Ryan. That's because lightness can translate to weakness—more broken bones and a higher incidence of osteoporosis and age-related bone loss. The researchers warn that with the deskbound lives that many people lead today, our bones may have become even more brittle than ever before. "We are not challenging our bones with enough loading," says Colin Shaw, "predisposing us to have weaker bones so that, as we age, situations arise where bones are breaking when, previously, they would not have." -
Scientists Say the Future Looks Bleak For Our Bones
HughPickens.com writes Nicholas St. Fluer reports at The Atlantic that according to researchers, our convenient, sedentary way of life is making our bones weak foretelling a future with increasing fractures, breaks, and osteoporosis. For thousands of years, hunter-gatherers trekked on strenuous ventures for food with dense skeletons supporting their movements and a new study pinpoints the origin of weaker bones at the beginning of the Holocene epoch roughly 12,000 years ago, when humans began adopting agriculture. "Modern human skeletons have shifted quite recently towards lighter—more fragile, if you like—bodies. It started when we adopted agriculture. Our diets changed. Our levels of activity changed," says Habiba Chirchir. A second study attributes joint bone weakness to different levels of physical activity in ancient human societies, also related to hunting versus farming.
The team scanned circular cross-sections of seven bones in the upper and lower limb joints in chimpanzees, Bornean orangutans and baboons. They also scanned the same bones in modern and early modern humans as well as Neanderthals, Paranthropus robustus, Australopithecus africanus and other Australopithecines. They then measured the amount of white bone in the scans against the total area to find the trabecular bone density. Crunching the numbers confirmed their visual suspicions. Modern humans had 50 to 75 percent less dense trabecular bone than chimpanzees, and some hominins had bones that were twice as dense compared to those in modern humans. Both studies have implications for modern human health and the importance of physical activity to bone strength. "The lightly-built skeleton of modern humans has a direct and important impact on bone strength and stiffness," says Tim Ryan. That's because lightness can translate to weakness—more broken bones and a higher incidence of osteoporosis and age-related bone loss. The researchers warn that with the deskbound lives that many people lead today, our bones may have become even more brittle than ever before. "We are not challenging our bones with enough loading," says Colin Shaw, "predisposing us to have weaker bones so that, as we age, situations arise where bones are breaking when, previously, they would not have." -
Study: Light-Emitting Screens Before Bedtime Disrupt Sleep
jfruh writes: Tablets and e-readers are more convenient in many ways than paper books, but many people have complained that the physical experience of using them isn't as good. And now we have some specific quantification of this fact: a study has shown that people who read text on a tablet before bed don't sleep as well as those who read a traditional book (abstract). -
Does Journal Peer Review Miss Best and Brightest?
sciencehabit writes: A study published today indicates that the scientific peer review system does a reasonable job of predicting the eventual interest in most papers, but it may fail when it comes to identifying really game-changing research. Papers that were accepted outright by one of the three elite journals tended to garner more citations than papers that were rejected and then published elsewhere (abstract). And papers that were rejected went on to receive fewer citations than papers that were approved by an editor. But there is a serious chink in the armor: All 14 of the most highly cited papers in the study were rejected by the three elite journals, and 12 of those were bounced before they could reach peer review. The finding suggests that unconventional research that falls outside the established lines of thought may be more prone to rejection from top journals. -
Want To Influence the World? Map Reveals the Best Languages To Speak
sciencehabit writes: Speak or write in English, and the world will hear you. Speak or write in Tamil or Portuguese, and you may have a harder time getting your message out. Now, a new method for mapping how information flows around the globe (abstract) identifies the best languages to spread your ideas far and wide. One hint: If you're considering a second language, try Spanish instead of Chinese. -
Photoswitch Therapy Restores Vision To Blind Lab Animals
Zothecula writes: A new genetic therapy that helped blind mice and dogs respond to light stimulus could restore sight to people who suffer from diseases such as retinitis pigmentosa (a gradual loss of vision from periphery inwards). The therapy uses chemicals known as photoswitches, which change shape when hit with light, to open the channels that activate retinal cells. Treated mice can distinguish between steady and flashing light (abstract), while dogs with late-stage retinal degeneration also regain some sensitivity to light. -
Asteroid Impacts May Have Formed Life's Building Blocks
sciencehabit writes: A high-powered laser in the Czech Republic has now provided provocative evidence that the hellish conditions produced when an asteroid or comet slams into Earth could have created some key building blocks of life on Earth. In a lab experiment intended to duplicate the high temperatures and pressures of such an impact (abstract), researchers used the laser to simultaneously make adenine, guanine, cytosine, and uracil, the four organic compounds in RNA, which many believe to have been the first molecule to encode genetic information. -
Study: HIV Becoming Less Deadly, Less Infectious
An anonymous reader writes: A new study (abstract) from Oxford University shows HIV is weakening as it evolves in response to our immune system. When the virus encounters somebody with a particularly strong immune system, it sacrifices efficiency in replication to gradually overcome those defenses. This causes it to take more time for the infection to cause AIDS. Professor Philip Goulder said, "It is quite striking. You can see the ability to replicate is 10% lower in Botswana than South Africa and that's quite exciting. We are observing evolution happening in front of us and it is surprising how quickly the process is happening. The virus is slowing down in its ability to cause disease and that will help contribute to elimination." Goulder added that the average time from infection to the onset of AIDS has increased by 25% over the past 10 years. -
Location of Spilled Oil From 2010 Deepwater Horizon Event Found
Chipmunk100 writes: A study published in the journal Proceedings of the National Academy of Sciences (abstract) claims to have identified the location of two million barrels of submerged oil thought to be trapped in the deep ocean following the 2010 Deepwater Horizon spill. By analyzing data from more than 3,000 samples collected at 534 locations over 12 expeditions, they identified a 1,250-square-mile patch of the deep sea floor upon which 2 to 16 percent of the discharged oil was deposited. The fallout of oil to the sea floor created thin deposits most intensive to the southwest of the Macondo well. The oil was most concentrated within the top half inch of the sea floor and was patchy even at the scale of a few feet." -
Glut of Postdoc Researchers Stirs Quiet Crisis In Science
HughPickens.com writes: Carolyn Johnson reports in the Boston Globe that in recent years, the position of postdoctoral researcher has become less a stepping stone and more of a holding tank. Postdocs are caught up in an all-but-invisible crisis, mired in an underclass as federal funding for research has leveled off, leaving the supply of well-trained scientists outstripping demand. "It's sunk in that it's by no means guaranteed — for anyone, really — that an academic position is possible," says Gary McDowell, a 29-year old biologist doing his second postdoc. "There's this huge labor force here to do the bench work, the grunt work of science. But then there's nowhere for them to go; this massive pool of postdocs that accumulates and keeps growing." The problem is that any researcher running a lab today is training far more people than there will ever be labs to run. Often these supremely well-educated trainees are simply cheap laborers, not learning skills for the careers where they are more likely to find jobs. This wasn't such an issue decades ago, but universities have expanded the number of PhD students they train from about 30,000 biomedical graduate students in 1979 to 56,800 in 2009, flooding the system with trainees and drawing out the training period.
Possible solutions span a wide gamut, from halving the number of postdocs over time, to creating a new tier of staff scientists that would be better paid. One thing people seem to agree on is that simply adding more money to the pot will not by itself solve the oversupply. Facing these stark statistics, postdocs are taking matters into their own hands, recently organizing a Future of Research conference in Boston that they hoped would give voice to their frustrations and hopes and help shape change. They ask, "How can we, as the next generation, run the system?" -
Genes Don't Just Predict Intelligence, But Also How Well You Do In School
sciencehabit writes: If you sailed through school with high grades and perfect test scores, you probably did it with traits beyond sheer smarts. A new study of more than 6000 pairs of twins finds that academic achievement is influenced by genes affecting motivation, personality, confidence, and dozens of other traits, in addition to those that shape intelligence (abstract). The results may lead to new ways to improve childhood education. -
Scientists Seen As Competent But Not Trusted By Americans
cold fjord writes The Woodrow Wilson School reports, "If scientists want the public to trust their research suggestions, they may want to appear a bit 'warmer,' according to a new review published by Princeton University's Woodrow Wilson School of Public and International Affairs. The review, published in the Proceedings of the National Academy of Sciences (PNAS), shows that while Americans view scientists as competent, they are not entirely trusted. This may be because they are not perceived to be friendly or warm. In particular, Americans seem wary of researchers seeking grant funding and do not trust scientists pushing persuasive agendas. Instead, the public leans toward impartiality. 'Scientists have earned the respect of Americans but not necessarily their trust,' said lead author Susan Fiske, the Eugene Higgins Professor of Psychology and professor of public affairs. 'But this gap can be filled by showing concern for humanity and the environment. Rather than persuading, scientists may better serve citizens by discussing, teaching and sharing information to convey trustworthy intentions.'" -
Study Links Pacific Coastal Warming To Changing Winds
tranquilidad writes: In a paper published by the Proceedings of the National Academy of Sciences, two authors ascribe the majority of northeast pacific coastal warming to natural atmospheric circulation and not to anthropogenic forcing. In AP's reporting, Ken Caldeira, an atmospheric scientist with the Carnegie Institution for Science, says the paper's authors, "...have not established the causes of these atmospheric pressure variations. Thus, claims that the observed temperature increases are due primarily to 'natural' processes are suspect and premature, at best." The paper's authors, on the other hand, state, "...clearly, there are other factors stronger than the greenhouse forcing that is affecting...temperatures," and that there is a "surprising degree to which the winds can explain all the wiggles in the temperature curve." -
Assembling a Micro-scale Biochemistry Lab Like Snapping LEGOs Together
An anonymous reader writes: Microfluidic systems promise to bring the same level of precision and control seen in the electronics industry to chemistry and the life sciences. Typically, devices are fabricated at substantial cost and using borrowed techniques from the semiconductor industry. Researchers at the USC Viterbi School of Engineering have invented a system of discrete microfluidic elements akin to those found in electronic board design. It was inspired by the ease with which LEGO bricks are assembled into a larger structure, and finally allows for the rapid prototyping of "Lab-on-Chip" devices. The original paper is published in the Proceedings of the National Academy of Science. -
Ancient Campfires Led To the Rise of Storytelling
sciencehabit writes A study of evening campfire conversations by the Ju/'hoan people of Namibia and Botswana suggests that by extending the day, fire allowed people to unleash their imaginations and tell stories, rather than merely focus on mundane topics. As scientists report, whereas daytime talk was focused almost entirely on economic issues, land rights, and complaints about other people, 81% of the firelight conversation was devoted to telling stories, including tales about people from other Ju/'hoan communities. The team suggests that campfires allowed human ancestors to expand their minds in a similar way and also solidified social networks. -
Massive Study Searching For Genes Behind Intelligence Finds Little
An anonymous reader writes: It's been taken for granted that science would, one day, figure out what parts of our DNA make us smart (or not). But a huge new study done by a group of almost 60 researchers using genome data on over 100,000 people has come up empty-handed. The scientists first looked for differences in the genome that correlated with academic achievement. After narrowing it down to 69 individual sites, they gave cognitive tests to separate group of 24,000 people and looked for evidence of difference at those same locations (abstract). Most of the sites weren't significantly different from chance — the (already weak) genetic influence of genes on height has an effect 20 times greater. On top of that, the three gene locations that did seem to have a stronger correlation weren't involved in development of the nervous system. -
Why Do Humans Grow Up So Slowly? Blame the Brain
sciencehabit (1205606) writes Humans are late bloomers when compared with other primates — they spend almost twice as long in childhood and adolescence as chimps, gibbons, or macaques do. But why? One widely accepted but hard-to-test theory is that children's brains consume so much energy that they divert glucose from the rest of the body, slowing growth. Now, a clever study of glucose uptake and body growth in children confirms this 'expensive tissue' hypothesis. -
Researchers Successfully Cut HIV DNA Out of Human Cells
mrspoonsi sends word that researchers from Temple University have managed to eliminate the HIV-1 virus from human cells for the first time. "When deployed, a combination of a DNA-snipping enzyme called a nuclease and a targeting strand of RNA called a guide RNA (gRNA) hunt down the viral genome and excise the HIV-1 DNA (abstract). From there, the cell's gene repair machinery takes over, soldering the loose ends of the genome back together – resulting in virus-free cells." While antiretroviral therapy can treat people who are infected with HIV, the immune system is incapable of actually removing the virus, so this is an important step in fighting it. The researchers still have to overcome the problem of delivering the the genetic "toolkit" to each affected cell in a patient's body, and also HIV's high mutation rate. -
Chemists Build First "Buckyball" Made of Boron
CelestialScience writes Researchers have built the first "buckyballs" composed entirely of boron. Unlike the original, carbon-based buckyballs, the boron molecules are not shaped like soccer balls, with tessellating pentagons and hexagons. Instead, they are molecular cages made up of hexagons, heptagons and triangles. As Lai-Sheng Wang of Brown University and colleagues report in the journal Nature Chemistry, each one contains 40 atoms, compared with carbon buckyballs which are made of 60. Boron is not the first element after carbon to get "buckyballed", but the boron balls may be the closest analogue to the carbon variety. Because of their reactivity, they could be useful for storing hydrogen. -
Ninety-Nine Percent of the Ocean's Plastic Is Missing
sciencehabit writes Millions of tons. That's how much plastic should be floating in the world's oceans, given our ubiquitous use of the stuff. But a new study (abstract) finds that 99% of this plastic is missing. One disturbing possibility: Fish are eating it. If that's the case, "there is potential for this plastic to enter the global ocean food web," says Carlos Duarte, an oceanographer at the University of Western Australia, Crawley. "And we are part of this food web." -
In 2012, Facebook Altered Content To Tweak Readers' Emotions
The Atlantic reports that two years ago, Facebook briefly conducted an experiment on a subset of its users, altering the mix of content shown to them to emphasize content sorted by tone, negative or positive, and observe the results. From the Atlantic article: For one week in January 2012, data scientists skewed what almost 700,000 Facebook users saw when they logged into its service. Some people were shown content with a preponderance of happy and positive words; some were shown content analyzed as sadder than average. And when the week was over, these manipulated users were more likely to post either especially positive or negative words themselves. This tinkering was just revealed as part of a new study, published in the prestigious Proceedings of the National Academy of Sciences. Many previous studies have used Facebook data to examine “emotional contagion,” as this one did. This study is different because, while other studies have observed Facebook user data, this one set out to manipulate it. At least they showed their work. -
The Game Theory of Life
An anonymous reader writes In what appears to be the first study of its kind, computer scientists report that an algorithm discovered more than 50 years ago in game theory and now widely used in machine learning is mathematically identical to the equations used to describe the distribution of genes within a population of organisms. Researchers may be able to use the algorithm, which is surprisingly simple and powerful, to better understand how natural selection works and how populations maintain their genetic diversity. -
Emotional Contagion Spread Through Facebook
Daniel_Stuckey sends this quote from Motherboard: It hopefully doesn't come as a surprise that your friends shape who you are. But we tend to think of that on a micro level: If your close circle of friends tends to have tattoos, wear polo shirts, or say "chill" a lot, it's quite possible that you'll emulate them over time — and they'll emulate you too. But what happens on a macro scale, when your friend circle doesn't just include the dozen people you actually hang out with regularly, but also the hundreds or thousands of acquaintances you have online? All of those feeds may seem filled with frivolities from random people (and they are!) but that steady stream of life updates — photos, rants, slang — are probably shaping you more than you think. A massive Facebook study recently published in PNAS found solid evidence of so-called emotional contagion—emotional states spreading socially, like a virus made of emoji—on the social network. -
Geothermal Heat Contributing To West Antarctic Ice Sheet Melting
bricko sends this news from The University of Texas at Austin: Thwaites Glacier, the large, rapidly changing outlet of the West Antarctic Ice Sheet, is not only being eroded by the ocean, it's being melted from below by geothermal heat, researchers at the Institute for Geophysics at The University of Texas at Austin (UTIG) report in the current edition of the Proceedings of the National Academy of Sciences. The findings significantly change the understanding of conditions beneath the West Antarctic Ice Sheet, where accurate information has previously been unobtainable. The Thwaites Glacier has been the focus of considerable attention in recent weeks as other groups of researchers found the glacier is on the way to collapse, but more data and computer modeling are needed to determine when the collapse will begin in earnest and at what rate the sea level will increase as it proceeds. The new observations by UTIG will greatly inform these ice sheet modeling efforts. -
Parenting Rewires the Male Brain
sciencehabit writes: "Cultures around the world have long assumed that women are hardwired to be mothers. But a new study (abstract) suggests that caring for children awakens a parenting network in the brain—even turning on some of the same circuits in men as it does in women. The research implies that the neural underpinnings of the so-called maternal instinct aren't unique to women, or activated solely by hormones, but can be developed by anyone who chooses to be a parent." -
Spanish Conquest May Have Altered Peru's Shoreline
sciencehabit (1205606) writes "The Spanish conquest of the Inca had a profound effect on Peru's indigenous people, but a new study reveals that it also had an unexpected impact on the land itself. Before the Spaniards arrived, inhabitants of the arid northern Peruvian coast clad massive sand dune-like ridges with an accidental form of 'armor': millions of discarded mollusk shells, which protected the ridges from erosion for nearly 4700 years and produced a vast corrugated landscape that is visible from space. This incidental landscape protection came to a swift end, however, after diseases brought by Spanish colonists decimated the local population and after colonial officials resettled the survivors inland. Without humans to create the protective covering, newly formed beach ridges simply eroded and vanished." -
What Caused a 1300-Year Deep Freeze?
sciencehabit (1205606) writes "Things were looking up for Earth about 12,800 years ago. The last Ice Age was coming to an end, mammoths and other large mammals romped around North America, and humans were beginning to settle down and cultivate wild plants. Then, suddenly, the planet plunged into a deep freeze, returning to near-glacial temperatures for more than a millennium before getting warm again. The mammoths disappeared at about the same time, as did a major Native American culture that thrived on hunting them. A persistent band of researchers has blamed this apparent disaster on the impact of a comet or asteroid, but a new study concludes that the real explanation for the chill, at least, may lie strictly with Earth-bound events." -
Controlling Fear By Modifying DNA
An anonymous reader writes "The fear of flying or of skittering spiders can mean more than just a momentary increase in heart rate and a pair of sweaty palms. A hard-core phobia can lead to crippling anxiety. Now an international team of researchers says it believes it has found a way to silence the gene that feeds phobic fear via a novel mechanism of gene regulation associated with fear extinction. The notion appears to be that phobias arise from experiences that have left an outsized imprint on gene expression, and that undoing this can undo the anxiety itself. The study was published this month (abstract) in the Proceedings of the National Academy of Sciences." -
Oklahoma Botched an Execution With Untested Lethal Injection Drugs
Daniel_Stuckey (2647775) writes "The state of Oklahoma had scheduled two executions for Tuesday, April 29th. This in spite of myriad objections that the drugs being used for both lethal injections had not been tested, and thus could violate the constitutional right to the courts, as well as the 8th Amendment: protection from cruel and unusual punishment. After much legal and political wrangling, the state proceeded with the executions anyway. It soon became clear that the critics' worst case scenarios were coming true — Oklahoma violently botched the first execution. The inmate "blew" a vein and had a heart attack. The state quickly postponed the second one. 'After weeks of Oklahoma refusing to disclose basic information about the drugs for tonight's lethal injection procedures, tonight, Clayton Lockett was tortured to death,' Madeline Cohen, the attorney of Charles Warner, the second man scheduled for execution, said in a statement. Katie Fretland at The Guardian reported from the scene of the botched attempt to execute Lockett using the untested, unvetted, and therefore potentially unconstitutional lethal injection drugs." sciencehabit also points out a study indicating that around 4% of death row inmates in the U.S. are likely innocent. -
Proposed Indicator of Life On Alien Worlds May Be Bogus
sciencehabit (1205606) writes with bad news for anyone hoping to use the spectral signatures of exoplanets to determine if their atmospheres have life-enabling compositions. "Call it the cosmic version of fool's gold. What was once considered a sure-fire sign of life on distant planets may not be so sure-fire after all, a new study suggests. The signal—a strong chemical imbalance in the planet's atmosphere that could only be generated by thriving ecosystems—could instead be the combined light from a lifeless exoplanet and its equally barren moon."