Climate Change Increases Risk of Crop Slowdown in Next 20 Years

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The world faces a small but substantially increased risk over the next two decades of a major slowdown in the growth of global crop yields because of climate change, new research finds.The authors, from Stanford University and the National Center for Atmospheric Research (NCAR), say the odds of a major production slowdown of wheat and corn even with a warming climate are not very high. But the risk is about 20 times more significant than it would be without global warming, and it may require planning by organizations that are affected by international food availability and price.”Climate change has substantially increased the prospect that crop production will fail to keep up with rising demand in the next 20 years,” said NCAR scientist Claudia Tebaldi, a co-author of the study.Stanford professor David Lobell said he wanted to study the potential impact of climate change on agriculture in the next two decades because of questions he has received from stakeholders and decision makers in governments and the private sector.”I’m often asked whether climate change will threaten food supply, as if it’s a simple yes or no answer,” Lobell said. “The truth is that over a 10- or 20-year period, it depends largely on how fast Earth warms, and we can’t predict the pace of warming very precisely. So the best we can do is try to determine the odds.”Lobell and Tebaldi used computer models of global climate, as well as data about weather and crops, to calculate the chances that climatic trends would have a negative effect of 10 percent on yields of corn and wheat in the next 20 years. This would have a major impact on food supply. Yields would continue to increase but the slowdown would effectively cut the projected rate of increase by about half at the same time that demand is projected to grow sharply.They found that the likelihood of natural climate shifts causing such a slowdown over the next 20 years is only 1 in 200. But when the authors accounted for human-induced global warming, they found that the odds jumped to 1 in 10 for corn and 1 in 20 for wheat.The study appears in this month’s issue of Environmental Research Letters. It was funded by the National Science Foundation (NSF), which is NCAR’s sponsor, and by the U.S. Department of Energy (DOE).More crops needed worldwideGlobal yields of crops such as corn and wheat have typically increased by about 1-2 percent per year in recent decades, and the U.N. Food and Agriculture Organization projects that global production of major crops will increase by 13 percent per decade through 2030 — likely the fastest rate of increase during the coming century. …


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#Agriculture, #Alternative-Medicine, #Atmospheric, #Cancer, #Department, #Environmental, #Ncar, #Private

Meet your match: Using algorithms to spark collaboration between scientists

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Speed dating, in which potential lovers size each other up in brief 10 minute encounters before moving on to the next person, can be an awkward and time-wasting affair. Finding the perfect research partnership is often just as tough. Speed dating-style techniques are increasingly used at academics conferences, but can be equally frustrating — with busy academics being pushed into too many pointless encounters.But now a group of scientists led by geneticist Rafael Carazo Salas have constructed a system that could revolutionise conference speed dating — by treating scientists like genes.Using mathematical algorithms, the team created a method of matching conference-goers according to pre-set criteria, bringing about unforeseen collaboration opportunities while also enabling “would-like-to-meet” match-ups across disciplines and knowledge areas. The results have been recently published in the open-access journal eLife.Funded by the Royal Society to run a small-scale satellite conference on cell polarity, the researchers wanted to find a way to not only break the ice between scientists who did not know each other, but also to “break the heat” — to encourage big name scientists to step outside of their usual small circle, and mix with up-and-coming scientists.”We wanted to avoid the usual pattern that happens at conferences, especially at interdisciplinary meetings, of like sticking with like. Then we came up with an idea — what if we treated the delegates like we treat genes, and used mathematical algorithms to build a connectivity picture that could enable new links to be made?” said Carazo Salas, from the Gurdon Institute and Genetics Department of Cambridge University, who co-developed the technique with colleagues Federico Vaggi and Attila Csikasz-Nagy from Fondazione Edmund Mach, Italy.In the lead-up to the conference, delegates were asked to submit information about their research areas and disciplines and also to come up with a ‘wish list’ of specialist areas that they would like to know more about.”The conference started in a predictable way. After the first couple of talks, questions came entirely from people in the first few rows. We then did a brief presentation about the “speed dating” session that was about to happen. People’s eyes lit up when they got the game — the notion of being treated like genes seemed to appeal.”In the first speed-dating round, the 40 delegates were each paired up with someone who was not known to them and who had a very different knowledge base — so someone specialising in X technique might be paired with a specialist in Y. Pairs were given around 10 minutes to talk and then moved on to new pairs, so that each person met a total of four other people they knew very little about.”The atmosphere in the room after the first round of speed dating was entirely different. There was a buzz, and at the next set of talks questions came from all over the room, not just the usual couple of rows at the front.”In the second round, the pairings made use of the wish lists the delegates had created. …


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#Academics, #Alzheimer, #Carazo, #Conference, #Department, #Institute, #Lovers, #Pregnancy, #Research, #Royal, #Scientists, #Style

Clinical opinion published on use of maternal oxygen during labor

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When a fetal heartbeat pattern becomes irregular during labor, many practitioners give oxygen to the mother. But questions remain whether this oxygen supplementation benefits the fetus or may actually be potentially harmful.A clinical opinion written by third year resident Maureen Hamel, MD, along with maternal-fetal medicine specialists Brenna Anderson, MD and Dwight Rouse, MD, of the Department of Obstetrics and Gynecology at Women & Infants Hospital of Rhode Island and The Warren Alpert Medical School of Brown University, has been published in the January 10, 2014 online edition of the American Journal of Obstetrics & Gynecology.The manuscript, entitled “Oxygen for intrauterine resuscitation: Of unproved benefit and potentially harmful,” aimed to make recommendations about the safety of the use of maternal oxygen supplementation in laboring women.According to lead author Dr. Hamel, “Maternal oxygen is often given to laboring women to improve fetal metabolic status or in an attempt to alleviate non-reassuring fetal heart rate patterns. However, there are only two randomized trials investigating the use of maternal oxygen supplementation in laboring women. These studies did not find that supplementation is likely to benefit the fetus and may even be harmful.”Based on their research, the team concludes that until it is studied properly in a randomized clinical trial, maternal oxygen supplementation in labor should be reserved for maternal hypoxia (lack of oxygen) and should not be considered an indicated intervention for non-reassuring fetal status.Story Source:The above story is based on materials provided by Women & Infants Hospital. Note: Materials may be edited for content and length.


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Evidence mixed on the usefulness of echinacea for colds

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For people seeking a natural treatment for the common cold, some preparations containing the plant Echinacea work better than nothing, yet “evidence is weak,” finds a new report from The Cochrane Library. The evidence review revealed no significant reductions in preventing illness, but didn’t rule out “small preventive effects.”The six authors conducted reviews on this subject in 1998, 2006 and 2008 and wanted to do an update to include several new trials conducted since then. “We’ve been doing this for so long and are very familiar with past research — which has been mixed from the very beginning,” said author Bruce Barrett, M.D., Ph.D. in the department of family medicine at the University of Wisconsin in Madison.The research team reviewed 24 randomized controlled trials to determine whether Echinacea was a safe and effective cold prevention and treatment. Trials included 4631 participants and 33 preparations, along with placebo. Echinacea products studied in these trials varied widely according to characteristics of three different plant species, the part of the plant used and method of manufacturing.People who get colds spend $8 billion annually on pharmaceutical products, including supplements such as Echinacea, Barrett noted. The authors’ meta-analyses suggest that at least some Echinacea preparations may reduce the relative risk of catching a cold by 10 to 20 percent, a small effect of unclear clinical significance. The most important recommendation from the review for consumers and clinicians is a caution that Echinacea products differ greatly and that the overwhelming majority of these products have not been tested in clinical trials.Barrett added that “it looks like taking Echinacea may reduce the incidence of colds. For those who take it as a treatment, some of the trials report real effects — but many do not. Bottom line: Echinacea may have small preventive or treatment effects, but the evidence is mixed.”"The paper does support the safety and efficacy of Echinacea in treating colds and highlights the main issue of standardizing herbal medicines,” commented Ron Eccles, Ph.D., director of the Common Cold Centre & Healthcare Clinical Trials at Cardiff University’s School of Biosciences in Wales.Story Source:The above story is based on materials provided by Health Behavior News Service, part of the Center for Advancing Health. …


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The ups and downs of early atmospheric oxygen

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UC Riverside research team challenges conventional view of a simple two-step rise in early oxygen on Earth; study suggests instead dynamic oxygen concentrations that rose and fell over billions of years.A team of biogeochemists at the University of California, Riverside, give us a nontraditional way of thinking about the earliest accumulation of oxygen in the atmosphere, arguably the most important biological event in Earth history.A general consensus asserts that appreciable oxygen first accumulated in Earth’s atmosphere around 2.3 billion years ago during the so-called Great Oxidation Event (GOE). However, a new picture is emerging: Oxygen production by photosynthetic cyanobacteria may have initiated as early as 3 billion years ago, with oxygen concentrations in the atmosphere potentially rising and falling episodically over many hundreds of millions of years, reflecting the balance between its varying photosynthetic production and its consumption through reaction with reduced compounds such as hydrogen gas.”There is a growing body of data that points to oxygen production and accumulation in the ocean and atmosphere long before the GOE,” said Timothy W. Lyons, a professor of biogeochemistry in the Department of Earth Sciences and the lead author of the comprehensive synthesis of more than a decade’s worth of study within and outside his research group.Lyons and his coauthors, Christopher T. Reinhard and Noah J. Planavsky, both former UCR graduate students, note that once oxygen finally established a strong foothold in the atmosphere starting about 2.3 billion years ago it likely rose to high concentrations, potentially even levels like those seen today. Then, for reasons not well understood, the bottom fell out, oxygen plummeted to a tiny fraction of today’s level, and the ocean remained mostly oxygen free for more than a billion years.The paper appears in Nature on Feb. 19.”This period of extended low oxygen spanning from roughly 2 to less than 1 billion years ago was a time of remarkable chemical stability in the ocean and atmosphere,” Lyons said.His research team envisions a series of interacting processes, or feedbacks, that maintained oxygen at very low levels principally by modulating the availability of life-sustaining nutrients in the ocean and thus oxygen-producing photosynthetic activity.”We suggest that oxygen was much lower than previously thought during this important middle chapter in Earth history, which likely explains the low abundances and diversity of eukaryotic organisms and the absence of animals,” Lyons said.The late Proterozoic — the time period beginning less than a billion years ago following this remarkable chapter of sustained low levels of oxygen — was strikingly different, marked by extreme climatic events manifest in global-scale glaciation, indications of at least intervals of modern-like oxygen abundances, and the emergence and diversification of the earliest animals. Lyons notes that the factors controlling the rise of animals are under close scrutiny, including challenges to the long-held view that a major rise in atmospheric oxygen concentrations triggered the event.”Despite the new ideas about animal origins, we suspect that oxygen played a major if not dominant role in the timing of that rise and, in particular, in the subsequent emergence of complex ecologies for animal life on and within the sediment, predator-prey relationships, and large bodies” said Lyons. “But, again, feedbacks always rule the day. Environmental change drives evolution, and steps in the progression of life change the environment.”No single factor is likely to be the whole story, and there is much more to be written in the tale. …


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#Cancer, #Department, #Earth, #Health, #Nature, #Research, #Riverside, #Science

Roots to shoots: Hormone transport in plants deciphered

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Plant growth is orchestrated by a spectrum of signals from hormones within a plant. A major group of plant hormones called cytokinins originate in the roots of plants, and their journey to growth areas on the stem and in leaves stimulates plant development. Though these phytohormones have been identified in the past, the molecular mechanism responsible for their transportation within plants was previously poorly understood.Now, a new study from a research team led by biochemist Chang-Jun Liu at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory identifies the protein essential for relocating cytokinins from roots to shoots.The research is reported in the February 11 issue of Nature Communications.Cytokinins stimulate shoot growth and promote branching, expansion and plant height. Regulating these hormones also improves the longevity of flowering plants, tolerance to drought or other environmental stresses, and the efficiency of nitrogen-based fertilizers.Manipulating cytokinin distribution by tailoring the action of the transporter protein could be one way to increase biomass yield and stress tolerance of plants grown for biofuels or agriculture. “This study may open new avenues for modifying various important crops, agriculturally, biotechnologically, and horticulturally, to increase yields and reduce fertilizer requirements, for instance, while improving the exploitation of sustainable bioenergy resources,” Liu said.Using Arabidopsis, a small flowering plant related to mustard and cabbage that serves as a common experimental model, the researchers studied a large family of transport proteins called ATP-binding cassette (ABC) transporters, which act as a kind of inter- or intra-cellular pump moving substances in or out of a plant’s cells or their organelles. While performing gene expression analysis on a set of these ABC transporters, the research team found that one gene — AtABCG14 – is highly expressed in the vascular tissues of roots.To determine its function, they examined mutant plants harboring a disrupted AtABCG14 gene. They found that knocking out this transporter gene resulted in plants with weaker growth, slenderer stems, and shorter primary roots than their wild-type counterparts. These structural changes in the plants are symptoms of cytokinin deficiencies. Essentially, the long-distance transportation of the growth hormones is impaired, which causes alterations in the development of roots and shoots. …


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The musical brain: Novel study of jazz players shows common brain circuitry processes both music, language

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The brains of jazz musicians engrossed in spontaneous, improvisational musical conversation showed robust activation of brain areas traditionally associated with spoken language and syntax, which are used to interpret the structure of phrases and sentences. But this musical conversation shut down brain areas linked to semantics — those that process the meaning of spoken language, according to results of a study by Johns Hopkins researchers.The study used functional magnetic resonance imaging (fMRI) to track the brain activity of jazz musicians in the act of “trading fours,” a process in which musicians participate in spontaneous back and forth instrumental exchanges, usually four bars in duration. The musicians introduce new melodies in response to each other’s musical ideas, elaborating and modifying them over the course of a performance.The results of the study suggest that the brain regions that process syntax aren’t limited to spoken language, according to Charles Limb, M.D., an associate professor in the Department of Otolaryngology-Head and Neck Surgery at the Johns Hopkins University School of Medicine. Rather, he says, the brain uses the syntactic areas to process communication in general, whether through language or through music.Limb, who is himself a musician and holds a faculty appointment at the Peabody Conservatory, says the work sheds important new light on the complex relationship between music and language.”Until now, studies of how the brain processes auditory communication between two individuals have been done only in the context of spoken language,” says Limb, the senior author of a report on the work that appears online Feb. 19 in the journal PLOS ONE. “But looking at jazz lets us investigate the neurological basis of interactive, musical communication as it occurs outside of spoken language.”We’ve shown in this study that there is a fundamental difference between how meaning is processed by the brain for music and language. Specifically, it’s syntactic and not semantic processing that is key to this type of musical communication. Meanwhile, conventional notions of semantics may not apply to musical processing by the brain.”To study the response of the brain to improvisational musical conversation between musicians, the Johns Hopkins researchers recruited 11 men aged 25 to 56 who were highly proficient in jazz piano performance. During each 10-minute session of trading fours, one musician lay on his back inside the MRI machine with a plastic piano keyboard resting on his lap while his legs were elevated with a cushion. A pair of mirrors was placed so the musician could look directly up while in the MRI machine and see the placement of his fingers on the keyboard. …


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Nothing so sweet as a voice like your own, study finds

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Have you ever noticed that your best friends speak the same way? A new University of British Columbia study finds we prefer voices that are similar to our own because they convey a soothing sense of community and social belongingness.While previous research has suggested that we prefer voices that sound like they are coming from smaller women or bigger men, the new study — published today in the journal PLOS ONE — identifies a variety of other acoustic signals that we find appealing.”The voice is an amazingly flexible tool that we use to construct our identity,” says lead author Molly Babel, a professor in the Department of Linguistics. “Very few things in our voices are immutable, so we felt that our preferences had to be about more than a person’s shape and size.”Aside from identifying the overwhelming allure of one’s own regional dialects, the study finds key gender differences. Among North Americans, it showed a preference for men who spoke with a shorter average word length. The researchers also found a preference for “larger” sounding male voices, a finding that supports previous research.For females, there was also a strong preference for breathier voices — a la Marilyn Monroe — as opposed to the creakier voices of the Kardashians or actress Ellen Page. The allure of breathiness — which typically results from younger and thinner vocal cords — relates to our cultural obsession with youthfulness and health, the researchers say. A creaky voice might suggest a person has a cold, is tired or smokes regularly.Babel says the findings indicate that our preference for voices aren’t all about body size and finding a mate, it is also about fitting in to our social groups.BackgroundBabel and her colleagues at the University of California, Santa Cruz asked college-aged participants in California to rate the attractiveness of male and female voices from people living west of the Mississippi River.They found that participants preferred different acoustic signals for males and females — and the strongest predictors of voice preference are specific to the community that you’re a part of.For example, the Californian participants had a strong preference for female voices that pronounced the “oo” vowel sound from a word like “goose” further forward in the mouth. This has been a characteristic of California speech since at least the early 1980′s. In many other regions of North America, people would pronounce the “oo” sound farther back in the mouth, as one might hear in the movie Fargo.The preference for males who had shorter average word length relates to a difference between how men and women speak. In North American English, longer average word length is a style typically used by women while shorter average word length is one used by men. …


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#Agriculture, #Alzheimer, #America, #Belongingness, #California, #Department, #Friends, #Professor, #River, #Social, #University

Bats inspire "micro air vehicle" designs: Small flying vehicles, complete with flapping wings, may now be designed

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By exploring how creatures in nature are able to fly by flapping their wings, Virginia Tech researchers hope to apply that knowledge toward designing small flying vehicles known as “micro air vehicles” with flapping wings.More than 1,000 species of bats have hand membrane wings, meaning that their fingers are essentially “webbed” and connected by a flexible membrane. But understanding how bats use their wings to manipulate the air around them is extremely challenging — primarily because both experimental measurements on live creatures and the related computer analysis are quite complex.In Virginia Tech’s study of fruit bat wings, the researchers used experimental measurements of the movements of the bats’ wings in real flight, and then used analysis software to see the direct relationship between wing motion and airflow around the bat wing. They report their findings in the journal Physics of Fluids.”Bats have different wing shapes and sizes, depending on their evolutionary function. Typically, bats are very agile and can change their flight path very quickly — showing high maneuverability for midflight prey capture, so it’s of interest to know how they do this,” explained Danesh Tafti, the William S. Cross professor in the Department of Mechanical Engineering and director of the High Performance Computational Fluid Thermal Science and Engineering Lab at Virginia Tech.To give you an idea of the size of a fruit bat, it weighs roughly 30 grams and a single fully extended wing is about 17 x 9 cm in length, according to Tafti.Among the biggest surprises in store for the researchers was how bat wings manipulated the wing motion with correct timing to maximize the forces generated by the wing. “It distorts its wing shape and size continuously during flapping,” Tafti noted.For example, it increases the area of the wing by about 30 percent to maximize favorable forces during the downward movement of the wing, and it decreases the area by a similar amount on the way up to minimize unfavorable forces. The force coefficients generated by the wing are “about two to three times greater than a static airfoil wing used for large airplanes,” said Kamal Viswanath, a co-author who was a graduate research assistant working with Tafti when the work was performed and is now a research engineer at the U.S. Naval Research Lab’s Laboratories for Computational Physics and Fluid Dynamics.This study was just an initial step in the researchers’ work. “Next, we’d like to explore deconstructing the seemingly complex motion of the bat wing into simpler motions, which is necessary to make a bat-inspired flying robot,” said Viswanath. The researchers also want to keep the wing motion as simple as possible, but with the same force production as that of a real bat.”We’d also like to explore other bat wing motions, such as a bat in level flight or a bat trying to maneuver quickly to answer questions, including: What are the differences in wing motion and how do they translate to air movement and forces that the bat generates? …


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#American, #Area, #Cancer, #Computational, #Cross, #Department, #Engineering, #Flight, #Health, #Pregnancy, #Virginia

Massachusetts" fire-safe cigarette law appears to decrease likelihood of residential fires

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A six-year-old Massachusetts law requiring that only “fire-safe” cigarettes (FSCs) be sold in the state appears to decrease the likelihood of unintentional residential fires caused by cigarettes by 28%, according to a new study by Harvard School of Public Health (HSPH) researchers.The study will appear online February 13, 2014 in the American Journal of Public Health.”This study is the first rigorous population-based study to evaluate the effectiveness of the fire-safe cigarette standards, and shows that science-based tobacco product regulation can protect the public health,” said lead author Hillel Alpert, research scientist at the Center for Global Tobacco Control at HSPH.Burning cigarettes left smoldering on a bed, furniture, or other flammable material are a leading cause of residential fires in the United States, generating hundreds of millions of dollars each year in property damage, health care costs, lost productivity, death, and injuries. Young children, seniors, African Americans, Native Americans, the poor, people living in rural areas or in substandard housing, and firefighters are especially at risk.To evaluate the effectiveness of Massachusetts’ Fire Safe Cigarette Law, the researchers analyzed seven years of data from 2004 to 2010 on accidental residential fires, including 1,629 caused by cigarettes. The information was reported to the Massachusetts Fire Incident Reporting System, a system maintained by the Massachusetts Department of Fire Services.The results appear to show that the likelihood of unintentional residential fires caused by cigarettes decreased by 28% after the Massachusetts law was enacted in 2008. The largest reductions were among cigarette fires in which human factors, such as falling asleep while smoking, were involved, and among fires that were ignited on materials, which are the scenarios for which the standard was developed.”This study confirms that the fire standard compliant (FSC) cigarette law has reduced the number of fires from cigarettes started by igniting furniture and bedding as it was designed to do,” said Massachusetts Fire Marshal Stephen Coan.”We now have the science to support that all tobacco companies throughout the world should voluntarily make their cigarettes less likely to ignite fires,” said Gregory Connolly, professor of the practice of public health and director of the HSPH Center for Global Tobacco Control.Story Source:The above story is based on materials provided by Harvard School of Public Health. Note: Materials may be edited for content and length.


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#African, #American, #Cancer, #Control, #Department, #Law, #Public, #School

Interactive map of human genetic history revealed

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A global map detailing the genetic histories of 95 different populations across the world, showing likely genetic impacts of European colonialism, the Arab slave trade, the Mongol Empire and European traders near the Silk Road mixing with people in China, has been revealed for the first time.The interactive map, produced by researchers from Oxford University and UCL (University College London), details the histories of genetic mixing between each of the 95 populations across Europe, Africa, Asia and South America spanning the last four millennia.It can be accessed at: http://admixturemap.paintmychromosomes.com/The study, published this week in Science, simultaneously identifies, dates and characterises genetic mixing between populations. To do this, the researchers developed sophisticated statistical methods to analyse the DNA of 1490 individuals in 95 populations around the world. The work was chiefly funded by the Wellcome Trust and Royal Society.’DNA really has the power to tell stories and uncover details of humanity’s past.’ said Dr Simon Myers of Oxford University’s Department of Statistics and Wellcome Trust Centre for Human Genetics, co-senior author of the study.’Because our approach uses only genetic data, it provides information independent from other sources. Many of our genetic observations match historical events, and we also see evidence of previously unrecorded genetic mixing. For example, the DNA of the Tu people in modern China suggests that in around 1200CE, Europeans similar to modern Greeks mixed with an otherwise Chinese-like population. Plausibly, the source of this European-like DNA might be merchants travelling the nearby Silk Road.’The powerful technique, christened ‘Globetrotter’, provides insight into past events such as the genetic legacy of the Mongol Empire. Historical records suggest that the Hazara people of Pakistan are partially descended from Mongol warriors, and this study found clear evidence of Mongol DNA entering the population during the period of the Mongol Empire. Six other populations, from as far west as Turkey, showed similar evidence of genetic mixing with Mongols around the same time.’What amazes me most is simply how well our technique works,’ said Dr Garrett Hellenthal of the UCL Genetics Institute, lead author of the study. ‘Although individual mutations carry only weak signals about where a person is from, by adding information across the whole genome we can reconstruct these mixing events. Sometimes individuals sampled from nearby regions can have surprisingly different sources of mixing.’For example, we identify distinct events happening at different times among groups sampled within Pakistan, with some inheriting DNA from sub-Saharan Africa, perhaps related to the Arab Slave Trade, others from East Asia, and yet another from ancient Europe. …


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#Agriculture, #Alzheimer, #China, #Department, #Dna, #European, #Historical, #Slave, #Society, #Study, #Wellcome

Vitamin D provides relief for those with chronic hives, study shows

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A study by researchers at the University of Nebraska Medical Center shows vitamin D as an add-on therapy could provide some relief for chronic hives, a condition with no cure and few treatment options. An allergic skin condition, chronic hives create red, itchy welts on the skin and sometimes swelling. They can occur daily and last longer than six weeks, even years.Jill Poole, M.D., associate professor in the UNMC Department of Internal Medicine, was principal investigator of a study in the Feb. 7 edition of the Annals of Allergy, Asthma and Immunology. The two-year study looked at the role of over-the-counter vitamin D3 as a supplemental treatment for chronic hives.Over 12 weeks, 38 study participants daily took a triple-drug combination of allergy medications (one prescription and two over-the-counter drugs) and one vitamin D3, an over-the-counter supplement. Half of the patient’s took 600 IUs of vitamin D3 and the other half took 4000 IUs.Researchers found after just one week, the severity of patients’ symptoms decreased by 33 percent for both groups. But at the end of three months, the group taking 4000 IUs of vitamin D3 had a further 40 percent decrease in severity of their hives. The low vitamin D3 treatment group had no further improvement after the first week.”We consider the results in patients a significant improvement,” Dr. Poole said. “This higher dosing of readily available vitamin D3 shows promise without adverse effects. …


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New "pomegranate-inspired" design solves problems for lithium-ion batteries

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An electrode designed like a pomegranate — with silicon nanoparticles clustered like seeds in a tough carbon rind — overcomes several remaining obstacles to using silicon for a new generation of lithium-ion batteries, say its inventors at Stanford University and the Department of Energy’s SLAC National Accelerator Laboratory.”While a couple of challenges remain, this design brings us closer to using silicon anodes in smaller, lighter and more powerful batteries for products like cell phones, tablets and electric cars,” said Yi Cui, an associate professor at Stanford and SLAC who led the research, reported today in Nature Nanotechnology.”Experiments showed our pomegranate-inspired anode operates at 97 percent capacity even after 1,000 cycles of charging and discharging, which puts it well within the desired range for commercial operation.”The anode, or negative electrode, is where energy is stored when a battery charges. Silicon anodes could store 10 times more charge than the graphite anodes in today’s rechargeable lithium-ion batteries, but they also have major drawbacks: The brittle silicon swells and falls apart during battery charging, and it reacts with the battery’s electrolyte to form gunk that coats the anode and degrades its performance.Over the past eight years, Cui’s team has tackled the breakage problem by using silicon nanowires or nanoparticles that are too small to break into even smaller bits and encasing the nanoparticles in carbon “yolk shells” that give them room to swell and shrink during charging.The new study builds on that work. Graduate student Nian Liu and postdoctoral researcher Zhenda Lu used a microemulsion technique common in the oil, paint and cosmetic industries to gather silicon yolk shells into clusters, and coated each cluster with a second, thicker layer of carbon. These carbon rinds hold the pomegranate clusters together and provide a sturdy highway for electrical currents.And since each pomegranate cluster has just one-tenth the surface area of the individual particles inside it, a much smaller area is exposed to the electrolyte, thereby reducing the amount of gunk that forms to a manageable level.Although the clusters are too small to see individually, together they form a fine black powder that can be used to coat a piece of foil and form an anode. Lab tests showed that pomegranate anodes worked well when made in the thickness required for commercial battery performance.While these experiments show the technique works, Cui said, the team will have to solve two more problems to make it viable on a commercial scale: They need to simplify the process and find a cheaper source of silicon nanoparticles. One possible source is rice husks: They’re unfit for human food, produced by the millions of tons and 20 percent silicon dioxide by weight. According to Liu, they could be transformed into pure silicon nanoparticles relatively easily, as his team recently described in Scientific Reports.”To me it’s very exciting to see how much progress we’ve made in the last seven or eight years,” Cui said, “and how we have solved the problems one by one.”Story Source:The above story is based on materials provided by DOE/SLAC National Accelerator Laboratory. Note: Materials may be edited for content and length.


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#Accelerator, #Agriculture, #Alternative-Medicine, #Department, #Design, #Major, #Nanotechnology, #Silicon, #Slac, #Story, #Team

Fertilization destabilizes global grassland ecosystems

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A new study led by University of Minnesota researchers demonstrates that fertilization of natural grasslands — either intentionally or unintentionally as a side effect of global farming and industry — is having a destabilizing effect on global grassland ecosystems. Using a network of natural grassland research sites around the world called the Nutrient Network, the study represents the first time such a large experiment has been conducted using naturally occurring sites.Led by Yann Hautier, a Marie Curie Fellow associated with both the Department of Ecology, Evolution, and Behavior at the University of Minnesota and the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich, the research team included U of M associate professors Eric Seabloom and Elizabeth Borer, and research scientist Eric Lind, along with scientists from institutions around the world including Andy Hector at Oxford University’s Department of Plant Sciences. The findings were published on February 16 in the journal Nature.The researchers found that plant diversity in natural ecosystems creates more stable ecosystems over time because of less synchronized growth of plants. “This is sometimes called the portfolio effect,” says Seabloom. “If you have money in two investments and they’re both stocks, they’re going to track each other, but if one is a stock and one is a bond, they’re going to respond differently to the overall economy and are more likely to balance each other.”The researchers collected plants from each of the sites, then sorted, dried, and weighed them to monitor the number of species of plants and total amount of plants, or “biomass,” grown over time. They used this information to quantify species diversity and ecosystem stability. Says Hautier: “It was really striking to see the relationship between diversity and stability” and the similarities to data collected from artificial grasslands as part of a research effort called BioDepth, indicating that the results from natural grasslands of the Nutrient Network could be predicted from the results of artificial grasslands.”The results of our study emphasize that we need to consider not just how productive ecosystems are but also how stable they are in the long-term, and how biodiversity is related to both aspects of ecosystem functioning,” says Andy Hector.The researchers also found that grassland diversity and stability are reduced when fertilizer is added. Fertilizers are intentionally used in grassland to increase livestock fodder. Fertilizer addition is also occurring unintentionally in many places around the world because nitrogen, a common fertilizer, is released into the atmosphere from farming, industry, and burning fossil fuels. Rainfall brings nitrogen out of the atmosphere and on to grasslands, changing the growth and types of plant species. …


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#Alzheimer, #Biology, #Department, #Environmental, #Hautier, #Health, #King, #Network

Tinnitus study signals new advance in understanding link between exposure to loud sounds and hearing loss

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Leicester research reveals why hearing loss is correlated with auditory signals failing to get transmitted along the auditory nerve.A research team investigating tinnitus, from the University of Leicester, has revealed new insights into the link between the exposure to loud sounds and hearing loss.Their study, published this week in J Neurosci,, helps to understand how damage to myelin — a protection sheet around cells — alters the transmission of auditory signals occurring during hearing loss.The three-year study was derived from a PhD studentship funded by Action on Hearing Loss. It was led by Dr Martine Hamann, Lecturer in Neurosciences at the University’s Department of Cell Physiology and Pharmacology.Dr Hamann said: “A previous publication has shown that exposure to loud sound damages the myelin which is the protection sheet around cells. We have now shown the closer links between a deficit in the “myelin” sheath surrounding the auditory nerve and hearing loss. It becomes obvious why hearing loss is correlated with auditory signals failing to get transmitted along the auditory nerve.”Understanding cellular mechanisms behind hearing loss and tinnitus allows for developing strategies to prevent or alleviate the symptoms of deafness or tinnitus — for example by using specific drug therapies.”This new study is particularly important because it allows us to understand the pathway from exposure to loud sound leading to the hearing loss. We now have a better idea about the mechanisms behind the auditory signals failing to get transmitted accurately from the cochlea to the brain. Consequently, targeting myelin and promoting its repair after exposure to loud sound could be proven effective in noise induced hearing loss.”Dr Hamann added that getting to dissect the cellular mechanisms underlying hearing loss is likely to bring a very significant healthcare benefit to a wide population.She said: “Understanding mechanisms responsible for hearing loss represents a significant unmet need that is likely to increase as the incidence of the disorder increases due to an aging population and the increasing impact of recreational and workplace noise.”I am very excited by this research. The work will help prevention as well as progression into finding appropriate cures for hearing loss and possibly tinnitus developing from hearing loss.”Dr Hamann’s team at the University of Leicester included Thomas Tagoe who performed all the electrophysiological experiments, Matt Barker and Natalie Allcock who performed the electron microscopy and the imaging experiments. Andrew Jones, a project student in the lab performed computer modelling.Dr Ralph Holme Action on Hearing Loss’ Head of Biomedical Research says: ”We know that exposure to loud noise can lead to hearing loss. Protecting your ears should always be the first line of defence, but medical treatments to combat unavoidable or accidental exposure to noise are also urgently needed. The research we have been funding at University of Leicester makes an important contribution to increasing our understanding of how noise damages the hearing system — knowledge we hope will ultimately lead to medical treatments for this common type of hearing loss.”Story Source:The above story is based on materials provided by University of Leicester. …


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#Cancer, #Cell, #Department, #Health, #Hearing, #Hearingloss, #Leicester, #Pregnancy, #Result, #Science

America"s natural gas system is leaking methane and in need of a fix

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The first thorough comparison of evidence for natural gas system leaks confirms that organizations including the Environmental Protection Agency (EPA) have underestimated U.S. methane emissions generally, as well as those from the natural gas industry specifically.Natural gas consists predominantly of methane. Even small leaks from the natural gas system are important because methane is a potent greenhouse gas — about 30 times more potent than carbon dioxide. A study, “Methane Leakage from North American Natural Gas Systems,” published in the Feb. 14 issue of the journal Science, synthesizes diverse findings from more than 200 studies ranging in scope from local gas processing plants to total emissions from the United States and Canada.”People who go out and actually measure methane pretty consistently find more emissions than we expect,” said the lead author of the new analysis, Adam Brandt, an assistant professor of energy resources engineering at Stanford University. “Atmospheric tests covering the entire country indicate emissions around 50 percent more than EPA estimates,” said Brandt. “And that’s a moderate estimate.”The standard approach to estimating total methane emissions is to multiply the amount of methane thought to be emitted by a particular kind of source, such as leaks at natural gas processing plants or belching cattle, by the number of that source type in a region or country. The products are then totaled to estimate all emissions. The EPA does not include natural methane sources, like wetlands and geologic seeps.The national natural gas infrastructure has a combination of intentional leaks, often for safety purposes, and unintentional emissions, like faulty valves and cracks in pipelines. In the United States, the emission rates of particular gas industry components — from wells to burner tips — were established by the EPA in the 1990s.Since then, many studies have tested gas industry components to determine whether the EPA’s emission rates are accurate, and a majority of these have found the EPA’s rates too low. …


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#Agency, #Alzheimer, #Brandt, #California, #Count, #Department, #Energy, #Epa, #People, #Pregnancy, #Science

Superconductivity in orbit: Scientists find new path to loss-free electricity

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Brookhaven Lab researchers captured the distribution of multiple orbital electrons to help explain the emergence of superconductivity in iron-based materials. Armed with just the right atomic arrangements, superconductors allow electricity to flow without loss and radically enhance energy generation, delivery, and storage. Scientists tweak these superconductor recipes by swapping out elements or manipulating the valence electrons in an atom’s outermost orbital shell to strike the perfect conductive balance. Most high-temperature superconductors contain atoms with only one orbital impacting performance — but what about mixing those elements with more complex configurations?Now, researchers at the U.S. Department of Energy’s Brookhaven National Laboratory have combined atoms with multiple orbitals and precisely pinned down their electron distributions. Using advanced electron diffraction techniques, the scientists discovered that orbital fluctuations in iron-based compounds induce strongly coupled polarizations that can enhance electron pairing — the essential mechanism behind superconductivity. The study, set to publish soon in the journal Physical Review Letters, provides a breakthrough method for exploring and improving superconductivity in a wide range of new materials.While the effect of doping the multi-orbital barium iron arsenic — customizing its crucial outer electron count by adding cobalt — mirrors the emergence of high-temperature superconductivity in simpler systems, the mechanism itself may be entirely different.”Now superconductor theory can incorporate proof of strong coupling between iron and arsenic in these dense electron cloud interactions,” said Brookhaven Lab physicist and study coauthor Weiguo Yin. “This unexpected discovery brings together both orbital fluctuation theory and the 50-year-old ‘excitonic’ theory for high-temperature superconductivity, opening a new frontier for condensed matter physics.”Atomic Jungle GymImagine a child playing inside a jungle gym, weaving through holes in the multicolored metal matrix in much the same way that electricity flows through materials. This particular kid happens to be wearing a powerful magnetic belt that repels the metal bars as she climbs. This causes the jungle gym’s grid-like structure to transform into an open tunnel, allowing the child to slide along effortlessly. …


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#Agriculture, #Cancer, #Department, #Energy, #Health, #Office, #Physical, #Science, #Scientists, #Study

With their amazing necks, ants don"t need "high hopes" to do heavy lifting

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High hopes may help move a rubber tree plant (as the old song goes), but the real secret to the ant’s legendary strength may lie in its tiny neck joint.In the Journal of Biomechanics, researchers report that the neck joint of a common American field ant can withstand pressures up to 5,000 times the ant’s weight.”Ants are impressive mechanical systems — astounding, really,” said Carlos Castro, assistant professor of mechanical and aerospace engineering at The Ohio State University. “Before we started, we made a somewhat conservative estimate that they might withstand 1,000 times their weight, and it turned out to be much more.”The engineers are studying whether similar joints might enable future robots to mimic the ant’s weight-lifting ability on earth and in space.Other researchers have long observed ants in the field and guessed that they could hoist a hundred times their body weight or more, judging by the payload of leaves or prey that they carried. Castro and his colleagues took a different approach.They took the ants apart.”As you would in any engineering system, if you want to understand how something works, you take it apart,” he said. “That may sound kind of cruel in this case, but we did anesthetize them first.”The engineers examined the Allegheny mound ant (Formica exsectoides) as if it were a device that they wanted to reverse-engineer: they tested its moving parts and the materials it is made of.They chose this particular species because it’s common in the eastern United States and could easily be obtained from the university insectary. It’s an average field ant that is not particularly known for it’s lifting ability.They imaged ants with electron microscopy and X-rayed them with micro-computed tomography (micro-CT) machines. They placed the ants in a refrigerator to anesthetize them, then glued them face-down in a specially designed centrifuge to measure the force necessary to deform the neck and eventually rupture the head from the body.The centrifuge worked on the same principle as a common carnival ride called “the rotor.” In the rotor, a circular room spins until centrifugal force pins people to the wall and the floor drops out. In the case of the ants, their heads were glued in place on the floor of the centrifuge, so that as it spun, the ants’ bodies would be pulled outward until their necks ruptured.The centrifuge spun up to hundreds of rotations per second, each increase in speed exerting more outward force on the ant. At forces corresponding to 350 times the ants’ body weight, the neck joint began to stretch and the body lengthened. The ants’ necks ruptured at forces of 3,400-5,000 times their average body weight.Micro-CT scans revealed the soft tissue structure of the neck and its connection to the hard exoskeleton of the head and body. Electron microscopy images revealed that each part of the head-neck-chest joint was covered in a different texture, with structures that looked like bumps or hairs extending from different locations.”Other insects have similar micro-scale structures, and we think that they might play some kind of mechanical role,” Castro said. …


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#American, #Ants, #Case, #Department, #Health, #Professor, #Robotics, #Space, #United, #University

How chronic stress predisposes brain to mental disorders

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University of California, Berkeley, researchers have shown that chronic stress generates long-term changes in the brain that may explain why people suffering chronic stress are prone to mental problems such as anxiety and mood disorders later in life.Their findings could lead to new therapies to reduce the risk of developing mental illness after stressful events.Doctors know that people with stress-related illnesses, such as post-traumatic stress disorder (PTSD), have abnormalities in the brain, including differences in the amount of gray matter versus white matter. Gray matter consists mostly of cells — neurons, which store and process information, and support cells called glia — while white matter is composed of axons, which create a network of fibers that interconnect neurons. White matter gets its name from the white, fatty myelin sheath that surrounds the axons and speeds the flow of electrical signals from cell to cell.How chronic stress creates these long-lasting changes in brain structure is a mystery that researchers are only now beginning to unravel.In a series of experiments, Daniela Kaufer, UC Berkeley associate professor of integrative biology, and her colleagues, including graduate students Sundari Chetty and Aaron Freidman, discovered that chronic stress generates more myelin-producing cells and fewer neurons than normal. This results in an excess of myelin — and thus, white matter — in some areas of the brain, which disrupts the delicate balance and timing of communication within the brain.”We studied only one part of the brain, the hippocampus, but our findings could provide insight into how white matter is changing in conditions such as schizophrenia, autism, depression, suicide, ADHD and PTSD,” she said.The hippocampus regulates memory and emotions, and plays a role in various emotional disorders.Kaufer and her colleagues published their findings in the Feb. 11 issue of the journal Molecular Psychiatry.Does stress affect brain connectivity?Kaufer’s findings suggest a mechanism that may explain some changes in brain connectivity in people with PTSD, for example. One can imagine, she said, that PTSD patients could develop a stronger connectivity between the hippocampus and the amygdala — the seat of the brain’s fight or flight response — and lower than normal connectivity between the hippocampus and prefrontal cortex, which moderates our responses.”You can imagine that if your amygdala and hippocampus are better connected, that could mean that your fear responses are much quicker, which is something you see in stress survivors,” she said. “On the other hand, if your connections are not so good to the prefrontal cortex, your ability to shut down responses is impaired. So, when you are in a stressful situation, the inhibitory pathways from the prefrontal cortex telling you not to get stressed don’t work as well as the amygdala shouting to the hippocampus, ‘This is terrible!’ You have a much bigger response than you should.”She is involved in a study to test this hypothesis in PTSD patients, and continues to study brain changes in rodents subjected to chronic stress or to adverse environments in early life.Stress tweaks stem cellsKaufer’s lab, which conducts research on the molecular and cellular effects of acute and chronic stress, focused in this study on neural stem cells in the hippocampus of the brains of adult rats. These stem cells were previously thought to mature only into neurons or a type of glial cell called an astrocyte. The researchers found, however, that chronic stress also made stem cells in the hippocampus mature into another type of glial cell called an oligodendrocyte, which produces the myelin that sheaths nerve cells.The finding, which they demonstrated in rats and cultured rat brain cells, suggests a key role for oligodendrocytes in long-term and perhaps permanent changes in the brain that could set the stage for later mental problems. …


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#Adult, #Agriculture, #Brain, #California, #Communication, #Department, #Depression, #King, #Psychiatry

Crocodilians can climb trees and bask in the tree crowns

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When most people envision crocodiles and alligators, they think of them waddling on the ground or wading in water — not climbing trees. However, a University of Tennessee, Knoxville, study has found that the reptiles can climb trees as far as the crowns.Vladimir Dinets, a research assistant professor in the Department of Psychology, is the first to thoroughly study the tree-climbing and -basking behavior. The research is published in the journal Herpetology.Dinets and his colleagues observed crocodilian species on three continents — Australia, Africa and North America — and examined previous studies and anecdotal observations. They found that four species climbed trees — usually above water — but how far they ventured upward and outward varied by their sizes. The smaller crocodilians were able to climb higher and further than the larger ones. Some species were observed climbing as far as four meters high in a tree and five meters down a branch.”Climbing a steep hill or steep branch is mechanically similar, assuming the branch is wide enough to walk on,” the authors wrote. “Still, the ability to climb vertically is a measure of crocodiles’ spectacular agility on land.”The crocodilians seen climbing trees, whether at night or during the day, were skittish of being approached, jumping or falling into the water when an approaching observer was as far as 10 meters away. This response led the researchers to believe that the tree climbing and basking are driven by two conditions: thermoregulation and surveillance of habitat.”The most frequent observations of tree-basking were in areas where there were few places to bask on the ground, implying that the individuals needed alternatives for regulating their body temperature,” the authors wrote. “Likewise, their wary nature suggests that climbing leads to improved site surveillance of potential threats and prey.”The data suggests that at least some crocodilian species are able to climb trees despite lacking any obvious morphological adaptations to do so.”These results should be taken into account by paleontologists who look at changes in fossils to shed light on behavior,” said Dinets. “This is especially true for those studying extinct crocodiles or other Archosaurian taxa.”Dinets collaborated with Adam Britton from Charles Darwin University in Australia and Matthew Shirley from the University of Florida.Research by Dinets published in 2013 found another surprising crocodilian characteristic — the use of lures such as sticks to hunt prey. …


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#Africa, #Alternative-Medicine, #Climbing, #Count, #Department, #Dinets, #Journal, #Species, #Tennessee, #Tree, #Water