New Chinese herbal medicine has significant potential in treating hepatitis C, study suggests

ata from a late-breaking abstract presented at the International Liver CongressTM 2014 identifies a new compound, SBEL1, that has the ability to inhibit hepatitis C virus (HCV) activity in cells at several points in the virus’ lifecycle.[i]SBEL1 is a compound isolated from Chinese herbal medicines that was found to inhibit HCV activity by approximately 90%. SBEL1 is extracted from a herb found in certain regions of Taiwan and Southern China. In Chinese medicine, it is used to treat sore throats and inflammations. The function of SBEL1 within the plant is unknown and its role and origins are currently being investigated.Scientists pre-treated human liver cells in vitro with SBEL1 prior to HCV infection and found that SBEL1 pre-treated cells contained 23 percent less HCV protein than the control, suggesting that SBEL1 blocks virus entry. The liver cells transfected with an HCV internal ribosome entry site (IRES)-driven luciferase reporter that were treated with SBEL1 reduced reporter activity by 50% compared to control. This suggests that that SBEL1 inhibits IRES-mediated translation, a critical process for viral protein production.In addition, the HCV ribonucleic acid (RNA) levels were significantly reduced by 78 percent in HCV infected cells treated with SBEL1 compared to the control group. This demonstrates that SBEL1 may also affect the viral RNA replication process.Prof. Markus Peck-Radosavljevic, Secretary-General of the European Association for the Study of the Liver and Associate Professor of Medicine, University of Vienna, Austria, commented: “People infected with hepatitis C are at risk of developing severe liver damage including liver cancer and cirrhosis. In the past, less than 20 percent of all HCV patients were treated because the available treatments were unsuitable due to poor efficacy and high toxicity. Recent advances means that we can now virtually cure HCV without unpleasant side effects. …

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Coal plant closure in China led to improvements in children’s health

Decreased exposure to air pollution in utero is linked with improved childhood developmental scores and higher levels of brain-derived neurotrophic factor (BDNF), a key protein for brain development, according to a study looking at the closure of a coal-burning power plant in China led by researchers at the Columbia Center for Children’s Environmental Health at the Mailman School of Public Health.The study is the first to assess BDNF and cognitive development with respect to prenatal exposure to polycyclic aromatic hydrocarbons (PAH), a component of air pollution commonly emitted from coal burning. Results appear online in the journal PLOS ONE.The 2004 closure of a coal-burning power plant in Tongliang, China provided the opportunity to investigate the benefits to development and the impacts on BDNF associated with decreased levels of exposure to PAH. This study has linked decreases in air pollution with decreased levels of PAH-DNA adducts in cord blood, a biological marker of exposure, and reported an association between PAH exposure and adverse developmental outcomes in children born before the plant closure. Currently, coal-fired power plants produce more than 70% of China’s electricity.Deliang Tang, MD, DrPH, and his colleagues followed two groups of mother-child pairs from pregnancy into early childhood. One of the groups was made up of mothers pregnant while the coal power plant was still open and the other after it closed. Developmental delay was determined using a standardized test, the Gesell Developmental Schedule (GDS), which was adapted for the Chinese population. The GDS assesses children in four areas: motor skills, learned behaviors, language, and social adaptation.The researchers found that, as hypothesized, decreased PAH exposure resulting from the power plant closure was associated with both increased BDNF levels and increased developmental scores. PAH-DNA adducts were significantly lower in the babies born after the coal power plant shutdown as compared to those born before the closure, indicating a meaningful exposure reduction. Moreover, the researchers found that the mean level of BDNF was higher among children born after the closure of the power plant. The impacts of PAH exposure and BDNF on developmental scores was also analyzed considering all the children, including both the pre- and post-closure groups. …

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Nearly complete ‘chicken from hell,’ from mysterious dinosaur group

A team of researchers has announced the discovery of a bizarre, bird-like dinosaur, named Anzu wyliei, that provides paleontologists with their first good look at a dinosaur group that has been shrouded in mystery for almost a century. Anzu was described from three specimens that collectively preserve almost the entire skeleton, giving scientists a remarkable opportunity to study the anatomy and evolutionary relationships of Caenagnathidae (pronounced SEE-nuh-NAY-thih-DAY) — the long-mysterious group of theropod dinosaurs to which Anzu belongs.The three described fossil skeletons of Anzu were unearthed in North and South Dakota, from roughly 66 million-year-old rocks of the Hell Creek Formation, a rock unit celebrated for its abundant fossils of famous dinosaurs such as Tyrannosaurus rex and Triceratops. The scientific paper describing the discovery appears today in the freely-accessible journal PLOS ONE.The team of scientists who studied Anzu was led by Dr. Matthew Lamanna of Carnegie Museum of Natural History in Pittsburgh. Dr. Lamanna’s collaborators include Dr. Hans-Dieter Sues and Dr. Tyler Lyson of the Smithsonian Institution’s National Museum of Natural History in Washington, DC, and Dr. Emma Schachner of the University of Utah in Salt Lake City. According to Dr. …

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Predators delay pest resistance to Bt crops

Crops genetically modified with the bacterium Bt (Bacillus thuringiensis) produce proteins that kill pest insects. Steady exposure has prompted concern that pests will develop resistance to these proteins, making Bt plants ineffective.Cornell research shows that the combination of natural enemies, such as ladybeetles, with Bt crops delays a pest’s ability to evolve resistance to these insecticidal proteins.“This is the first demonstrated example of a predator being able to delay the evolution of resistance in an insect pest to a Bt crop,” said Anthony Shelton, a professor of entomology at Cornell University’s New York State Agricultural Experiment Station in Geneva, N.Y., and a co-author of the paper. Xiaoxia Liu, a visiting scientist from China Agricultural University who worked in the Shelton lab, is the lead author on the paper published in the journal PLoS One.Bt is a soil bacterium that produces proteins that are toxic to some species of caterpillars and beetles when they are ingested, but have been proven safe to humans and many natural enemies, including predaceous ladybirds. Bt genes have been engineered into a variety of crops to control insect pests.Since farmers began planting Bt crops in 1996 with 70 million hectares planted in the United States in 2012, there have been only three clear-cut cases in agriculture of resistance in caterpillars, and one in a beetle. “Resistance to Bt crops is surprisingly uncommon,” said Shelton.To delay or prevent insect pests from evolving resistance to Bt crops, the U.S. Environmental Protection Agency promotes the use of multiple Bt genes in plants and the practice of growing refuges of non-Bt plants that serve as a reservoir for insects with Bt susceptible genes.“Our paper argues there is another factor involved: the conservation of natural enemies of the pest species,” said Shelton. These predators can reduce the number of potentially resistant individuals in a pest population and delay evolution of resistance to Bt.In the study, the researchers set up large cages in a greenhouse. Each cage contained Bt broccoli and refuges of non-Bt broccoli. They studied populations of diamondback moth (Plutella xylostella) larvae, a pest of broccoli, and their natural enemies, ladybird beetles (Coleomegilla maculata), for six generations.Cages contained different combinations of treatments with and without predators, and with and without sprayed insecticides on the non-Bt refuge plants. Farmers commonly spray insecticides on refuge plants to prevent loss by pests, but such sprays can kill predators and prey indiscriminately.The results showed that diamondback moth populations were reduced in the treatment containing ladybird beetles and unsprayed non-Bt refuge plants. …

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Livestock found ganging up on pandas at the bamboo buffet

Pandas, it turns out, aren’t celebrating the Year of the Horse.Livestock, particularly horses, have been identified as a significant threat to panda survival. The reason: They’re beating the pandas to the bamboo buffet. A paper by Michigan State University panda habitat experts published in this week’s Journal for Nature Conservation explores an oft-hidden yet significant conflict in conservation.”Across the world, people are struggling to survive in the same areas as endangered animals, and often trouble surfaces in areas we aren’t anticipating,” said Jianguo “Jack” Liu, Rachel Carson Chair in Sustainability at Michigan State University (MSU). “Creating and maintaining successful conservation policy means constantly looking for breakdowns in the system. In this case, something as innocuous as a horse can be a big problem.”China invests billions to protect giant panda habitat and preserve the 1,600 remaining endangered wildlife icons living there. For years, timber harvesting has been the panda’s biggest threat. Pandas have specific habitat needs — they eat only bamboo and stay in areas with gentle slopes that are far from humans. Conservation programs that limit timber harvesting have chalked up wins in preserving such habitat.Vanessa Hull, a doctoral student in MSU’s Center for Systems Integration and Sustainability (CSIS), has been living off and on for seven years in the Wolong Nature Reserve, most recently tracking pandas she’s equipped with GPS collars. She has been working to better understand how these elusive and isolated animals move about and use natural resources.Over the years, she started noticing it wasn’t just pandas chowing on bamboo.”It didn’t take particular panda expertise to know that something was amiss when we’d come upon horse-affected bamboo patches. They were in the middle of nowhere and it looked like someone had been in there with a lawn mower,” Hull said.Alarmed by the growing devastation, she learned that some of Wolong’s farmers, who traditionally hadn’t kept horses, had been talking to friends outside of the reserve who had been cashing in by raising them. …

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Climate change puts wheat crops at risk of disease

There is a risk that severity of epidemics of some wheat diseases may increase within the next ten to twenty years due to the impacts of climate change according to a study by international researchers led by the University of Hertfordshire.The researchers carried out a survey in China to establish a link between weather and the severity of epidemics of fusarium ear blight on the wheat crops. This weather-based model was then used to predict the impact on severity of the disease of future weather scenarios for the period from 2020 to 2050.Professor Bruce Fitt, professor of plant pathology at the University of Hertfordshire’s School of Medical and Life Sciences, said: “There is considerable debate about the impact of climate change on crop production — and making sure that we have sufficient food to feed the ever-growing global population is key to our future food security.”Wheat, one of the world’s most important crops for human food, is milled for use in bread, breakfast cereals, cakes, pizzas, confectionery, soups and many other foodstuffs. Fusarium ear blight is a serious disease affecting wheat across many areas of the world. During severe epidemics, wheat crop losses can be as much as sixty per cent. These losses can become larger as, under certain conditions, the fusarium pathogen produces toxic chemicals known as mycotoxins. The levels of mycotoxins present in the grain may render it unsuitable for either human or animal consumption — the mycotoxin safe levels being controlled by legislation.Professor Fitt continued: “We know that the weather plays a big part in the development of the disease on the wheat crops — the incidence of the disease is determined by temperature and the occurrence of wet weather at the flowering or anthesis of the wheat crops.”When the weather-based model developed at Rothamsted Research was used to predict how climate change may affect the wheat crops, it was predicted that wheat flowering dates will generally be earlier and the incidence of the ear blight disease on the wheat crops will substantially increase.The research suggests that climate change will increase the risk of serious ear blight epidemics on winter wheat in Central China by the middle of this century (2020-2050).Similar conclusions were reached about impacts of climate change on wheat in the UK, where climate change models are predicting warmer, wetter winters for the country. This suggests that the UK too will suffer a greater incidence of fusarium ear blight on wheat crops — greatly affecting one of our biggest staple crops.In a world where more than one billion people do not have enough to eat, and our future food security is threatened by climate change and an ever-growing population, it is essential to improve the control of crop diseases like fusarium ear blight around the globe.Story Source:The above story is based on materials provided by University of Hertfordshire. Note: Materials may be edited for content and length.

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Powerful artificial muscles made from fishing line and sewing thread

An international team led by The University of Texas at Dallas has discovered that ordinary fishing line and sewing thread can be cheaply converted to powerful artificial muscles.The new muscles can lift a hundred times more weight and generate a hundred times higher mechanical power than the same length and weight of human muscle. Per weight, they can generate 7.1 horsepower per kilogram, about the same mechanical power as a jet engine.In a paper published Feb. 21 in the journal Science, researchers explain that the powerful muscles are produced by twisting and coiling high-strength polymer fishing line and sewing thread. Scientists at UT Dallas’s Alan G. MacDiarmid NanoTech Institute teamed with scientists from universities in Australia, South Korea, Canada, Turkey and China to accomplish the advances.The muscles are powered thermally by temperature changes, which can be produced electrically, by the absorption of light or by the chemical reaction of fuels. Twisting the polymer fiber converts it to a torsional muscle that can spin a heavy rotor to more than 10,000 revolutions per minute. Subsequent additional twisting, so that the polymer fiber coils like a heavily twisted rubber band, produces a muscle that dramatically contracts along its length when heated, and returns to its initial length when cooled. If coiling is in a different twist direction than the initial polymer fiber twist, the muscles instead expand when heated.Compared to natural muscles, which contract by only about 20 percent, these new muscles can contract by about 50 percent of their length. The muscle strokes also are reversible for millions of cycles as the muscles contract and expand under heavy mechanical loads.”The application opportunities for these polymer muscles are vast,” said corresponding author Dr. Ray Baughman, the Robert A. …

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Interactive map of human genetic history revealed

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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Mixed genes: Interactive world map of human genetic history reveals likely genetic impacts of historical events

When individuals from different groups interbreed, their offspring’s DNA becomes a mixture of the DNA from each admixing group. Pieces of this DNA are then passed along through subsequent generations, carrying on all the way to the present day. Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Oxford University and University College London (UCL) have now produced a global map detailing the genetic histories of 95 different populations across the world, spanning the last four millennia.The interactive world map that is accessible via the internet, details the histories of genetic mixing between each of the 95 populations across Europe, Africa, Asia and South America. It shows likely genetic impacts of historical events including European colonialism, the Mongol Empire, the Arab slave trade and European traders near the Silk Road mixing with people in China.The study, published this week in Science, is the first to simultaneously identify, date and characterise 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. “DNA really has the power to tell stories and uncover details of humanity’s past,” said 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. …

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Research examines acupuncture needle quality

The quality of needles used in acupuncture worldwide is high but needs to be universally improved to increase safety and avoid potential problems such as pain and allergic reactions, RMIT University researchers have found.The researchers looked at surface conditions and other physical properties of the two most commonly used stainless steel acupuncture needle brands.The study, published in Acupuncture in Medicine, found that although manufacturing processes have improved, surface irregularities and bent needle tips have not been entirely eliminated.Lead investigator Professor Mike Xie, Director of the Centre for Innovative Structures and Materials at RMIT, said acupuncture was a safe treatment overall but the research showed it could be made even safer.”In China, Chinese medicine including acupuncture, accounts for 40 per cent of all medical treatment, while in Western countries, acupuncture is one of the most frequently used complementary therapies,” he said.”Our findings show that acupuncture needle manufacturers should review and improve their quality control procedures for the fabrication of needles.”In particular, needle tips should be properly formed, sharpened and cleansed.”Extensive research on acupuncture has demonstrated its safety and benefit for a range of conditions. But more needs to be done to enhance the comfort and safety of patients undergoing acupuncture treatment worldwide.”China, Japan and Korea are the main suppliers of acupuncture needles, with China providing up to 90 per cent of the world’s acupuncture needles.In the study, scanning electron microscope images were taken of 10 randomly chosen needles from each brand, with further images taken after each needle underwent a standard manipulation — the equivalent of using them on human tissue — with an acupuncture needling practice gel.The images revealed significant surface irregularities and inconsistencies at the needle tips, particularly in needles from one of the brands.Metallic lumps and small, loosely attached pieces of material were observed on the surfaces of some needles. Some of these fragments disappeared after the acupuncture manipulation.Co-author Professor Charlie Xue, Director of the Traditional and Complementary Medicine Research Program in the Health Innovations Research Institute and Head of the School of Health Sciences at RMIT, said the metallic residue could be deposited in human tissues, causing discomfort and potentially allergic reactions such as dermatitis.”While acupuncture needle induced dermatitis has been extremely rare, it is important to minimise the potential for such reaction through further improvement of the needles used in human practice,” Professor Xue said.”Malformed needle tips can cause problems including bleeding, bruising, or strong pain during needling, which are more commonly reported following acupuncture treatment.”An off-centre needle tip could result in the needle altering its direction during insertion and manipulation, consequently damaging adjacent tissues.”While none of these potential problems would result in serious or long-term injury, patient experience and safety are paramount and the quality of acupuncture needles must be more rigorously improved.”The researchers suggested the small metallic pieces found on the needle surfaces were most likely from the grinding and polishing processes during the manufacture of the needles. These processes would also generate electrostatic forces that would attract tiny metal filings to the needle surfaces. The metallic pieces should have been removed from the needles if adequate cleansing processes had been carried out, the study found.Story Source:The above story is based on materials provided by RMIT University. Note: Materials may be edited for content and length.

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Brain process takes paper shape: Paper-based device mimics electrochemical signalling in human brain

A paper-based device that mimics the electrochemical signalling in the human brain has been created by a group of researchers from China.The thin-film transistor (TFT) has been designed to replicate the junction between two neurons, known as a biological synapse, and could become a key component in the development of artificial neural networks, which could be utilised in a range of fields from robotics to computer processing.The TFT, which has been presented today, 13 February, in IOP Publishing’s journal Nanotechnology, is the latest device to be fabricated on paper, making the electronics more flexible, cheaper to produce and environmentally friendly.The artificial synaptic TFT consisted of indium zinc oxide (IZO), as both a channel and a gate electrode, separated by a 550-nanometre-thick film of nanogranular silicon dioxide electrolyte, which was fabricated using a process known as chemical vapour deposition.The design was specific to that of a biological synapse — a small gap that exists between adjoining neurons over which chemical and electrical signals are passed. It is through these synapses that neurons are able to pass signals and messages around the brain.All neurons are electrically excitable, and can generate a ‘spike’ when the neuron’s voltage changes by large enough amounts. These spikes cause signals to flow through the neurons which cause the first neuron to release chemicals, known as neurotransmitters, across the synapse, which are then received by the second neuron, passing the signal on.Similar to these output spikes, the researchers applied a small voltage to the first electrode in their device which caused protons — acting as a neurotransmitter — from the silicon dioxide films to migrate towards the IZO channel opposite it.As protons are positively charged, this caused negatively charged electrons to be attracted towards them in the IZO channel which subsequently allowed a current to flow through the channel, mimicking the passing on of a signal in a normal neuron.As more and more neurotransmitters are passed across a synapse between two neurons in the brain, the connection between the two neurons becomes stronger and this forms the basis of how we learn and memorise things.This phenomenon, known as synaptic plasticity, was demonstrated by the researchers in their own device. They found that when two short voltages were applied to the device in a short space of time, the second voltage was able to trigger a larger current in the IZO channel compared to the first applied voltage, as if it had ‘remembered’ the response from the first voltage.Corresponding author of the study, Qing Wan, from the School of Electronic Science and Engineering, Nanjing University, said: ‘A paper-based synapse could be used to build lightweight and biologically friendly artificial neural networks, and, at the same time, with the advantages of flexibility and biocompatibility, could be used to create the perfect organism-machine interface for many biological applications.’Story Source:The above story is based on materials provided by Institute of Physics. Note: Materials may be edited for content and length.

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Giant mass extinction quicker than previously thought: End-Permian extinction happened in 60,000 years

The largest mass extinction in the history of animal life occurred some 252 million years ago, wiping out more than 96 percent of marine species and 70 percent of life on land — including the largest insects known to have inhabited Earth. Multiple theories have aimed to explain the cause of what’s now known as the end-Permian extinction, including an asteroid impact, massive volcanic eruptions, or a cataclysmic cascade of environmental events. But pinpointing the cause of the extinction requires better measurements of how long the extinction period lasted.Now researchers at MIT have determined that the end-Permian extinction occurred over 60,000 years, give or take 48,000 years — practically instantaneous, from a geologic perspective. The new timescale is based on more precise dating techniques, and indicates that the most severe extinction in history may have happened more than 10 times faster than scientists had previously thought.”We’ve got the extinction nailed in absolute time and duration,” says Sam Bowring, the Robert R. Shrock Professor of Earth and Planetary Sciences at MIT. “How do you kill 96 percent of everything that lived in the oceans in tens of thousands of years? It could be that an exceptional extinction requires an exceptional explanation.”In addition to establishing the extinction’s duration, Bowring, graduate student Seth Burgess, and a colleague from the Nanjing Institute of Geology and Paleontology also found that, 10,000 years before the die-off, the oceans experienced a pulse of light carbon, which likely reflects a massive addition of carbon dioxide to the atmosphere. This dramatic change may have led to widespread ocean acidification and increased sea temperatures by 10 degrees Celsius or more, killing the majority of sea life.But what originally triggered the spike in carbon dioxide? The leading theory among geologists and paleontologists has to do with widespread, long-lasting volcanic eruptions from the Siberian Traps, a region of Russia whose steplike hills are a result of repeated eruptions of magma. To determine whether eruptions from the Siberian Traps triggered a massive increase in oceanic carbon dioxide, Burgess and Bowring are using similar dating techniques to establish a timescale for the Permian period’s volcanic eruptions that are estimated to have covered over five million cubic kilometers.”It is clear that whatever triggered extinction must have acted very quickly,” says Burgess, the lead author of a paper that reports the results in this week’s Proceedings of the National Academy of Sciences, “fast enough to destabilize the biosphere before the majority of plant and animal life had time to adapt in an effort to survive.”Pinning dates on an extinctionIn 2006, Bowring and his students made a trip to Meishan, China, a region whose rock formations bear evidence of the end-Permian extinction; geochronologists and paleontologists have flocked to the area to look for clues in its layers of sedimentary rock. …

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Innovative technique creates large skin flaps for full-face resurfacing

Patients with massive burns causing complete loss of the facial skin pose a difficult challenge for reconstructive surgeons. Now a group of surgeons in China have developed an innovative technique for creating a one-piece skin flap large enough to perform full-face resurfacing, reports The Journal of Craniofacial Surgery, published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.Dr. QingFeng Li and colleagues of Shanghai Jiao Tong University School of Medicine describe their approach to creating “monoblock” flaps for use in extensive face skin resurfacing. In their successful experience with five severely disfigured patients, the full-face tissue flap “provides universally matched skin and near-normal facial contour.”New Technique Grows One-Piece Skin Flaps for Full-Face ResurfacingComplete destruction of the facial skin and underlying (subcutaneous) tissues presents “the most challenging dilemma” in facial reconstructive surgery. Multiple skin flaps and grafts are needed to provide complete coverage, creating a “patchwork” appearance. Standard skin grafts are also too bulky to provide good reconstruction of the delicate features and expressive movement of the normal facial skin.To meet these challenges, Dr. Li and colleagues have developed a new technique for creating a single, large skin flap appropriate for use in full-face resurfacing. Their approach starts with “prefabrication” of a flap of the patient’s own skin, harvested from another part of the body. The skin flap, along with its carefully preserved blood supply, is allowed to grow for some weeks in a “pocket” created under the patient’s skin of the patient’s upper chest.Tissue expanders — balloon-like devices gradually filled with saline solution — are used to enlarge the skin flap over time. While skin expansion is a standard technique for creation of skin flaps, Dr. …

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Pumping draws arsenic toward a big-city aquifer

Sep. 11, 2013 — Naturally occurring arsenic pollutes wells across the world, especially in south and southeast Asia, where an estimated 100 million people are exposed to levels that can cause heart, liver and kidney problems, diabetes and cancer. Now, scientists working in Vietnam have shown that massive pumping of groundwater from a clean aquifer is slowly but surely drawing the poison into the water. The study, done near the capital city of Hanoi, confirms suspicions that booming water usage there and elsewhere could eventually threaten millions more people.The study appears in the current issue of the journal Nature.”This is the first time we have been able to show that a previously clean aquifer has been contaminated,” said lead author Alexander van Geen, a geochemist at Columbia University’s Lamont-Doherty Earth Observatory. “The amount of water being pumped really dominates the system. Arsenic is moving.” The good news, he said: “It is not moving as fast as we had feared it might.” This will buy time — perhaps decades–for water managers to try and deal with the problem, he said.Arsenic is found in rocks across the world, but it seems to pollute groundwater only under specific conditions. The huge scale across south Asia came clear only in the 1990s, when researchers from universities, nonprofit agencies and governments started testing wells systematically. Van Geen has been working in the field for 13 years, and is leading a new collaborative effort in the region under the International Continental Scientific Drilling Program.Researchers link natural arsenic pollution in south Asia to vast amounts of sediment eroding off the Himalayan plateau into basins below, from Pakistan and India to China and Vietnam. The constant fresh supply reacts rapidly with local water, though the exact mechanisms of arsenic release have remained unclear, along with the potential effects of groundwater pumping. The new study clarifies some of the chemical processes, and shows clearly for the first time that human activity can widen the problem.Hanoi, like many metropolitan areas, is mushrooming in size, and using ever more groundwater. …

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China’s clean-water program benefits people and the environment

Sep. 5, 2013 — Rice farming near Beijing has contaminated and tapped the city’s drinking water supply. For the past four years, China has been paying farmers to grow corn instead of rice, an effort that Stanford research shows is paying off for people and the environment.Rice farming is more lucrative than corn for Chinese farmers, but flooded paddies contribute to decreased water quality and quantity.The brown, smog-filled skies that engulf Beijing have earned China a poor reputation for environmental stewardship. But despite China’s dirty skies, a study led by Stanford environmental scientists has found that a government-run clean water program is providing substantial benefit to millions of people in the nation’s capital.The Miyun reservoir, 100 miles north of Beijing, is the main water source for the city’s more than 20 million inhabitants. Greater agricultural demands and a decline in precipitation, among other factors, have cut the reservoir’s output by two-thirds since the 1960s. The water has also become increasingly polluted by fertilizer and sediment run-off, and poses a significant health risk.Similar conditions shut down Beijing’s second largest reservoir in 1997; shortly after, officials began implementing a plan to prevent the same from happening to the Miyun reservoir.The system follows the successful model established by New York City, in which the government and wealthier downstream consumers provide payouts to upstream farmers, who in turn modify their agricultural practices to improve water conditions.In the case of China’s Paddy Land-to-Dry Land (PLDL) program, farmers are paid to convert their croplands from rice to corn, a solution that reduces both water consumption and pollution. Rice paddies are constantly flooded and are often situated on steep slopes, leading to significant fertilizer and sediment runoff. Corn, meanwhile, requires much less water, and fertilizer is more likely to stay in the soil.Improving rural lifeThe program is indicative of China’s recent efforts to improve living conditions for its rural citizens.”At the top, China sees environmental protection and poverty alleviation as vital to national security,” said Gretchen Daily, a biology professor at Stanford and senior co-author on the study. “The challenge is in implementing change. It’s amazing that in four short years, the government got everyone growing rice in this area to switch to corn, which greatly improved both water quality and the quantity that reaches city residents downstream.”Farmers earn almost six times more money growing rice than corn, so the government compensated farmers with funds that more than made up the difference. …

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Rare fossil ape cranium discovered in China

Sep. 6, 2013 — A team of researchers has discovered the cranium of a fossil ape from Shuitangba, a Miocene site in Yunnan Province, China. The juvenile cranium of the fossil ape Lufengpithecus is significant, according to team member Nina Jablonski, Distinguished Professor of Anthropology at Penn State.Jablonski noted that juvenile crania of apes and hominins are extremely rare in the fossil record, especially those of infants and young juveniles. This cranium is only the second relatively complete cranium of a young juvenile in the entire Miocene — 23-25 million years ago — record of fossil apes throughout the Old World, and both were discovered from the late Miocene of Yunnan Province.The cranium is also noteworthy for its age. Shuitangba, the site from which it was recovered, at just over 6 million years old, dates to near the end of the Miocene, a time when apes had become extinct in most of Eurasia. Shuitangba has also produced remains of the fossil monkey, Mesopithecus, which represents the earliest occurrence of monkeys in East Asia.Jablonski was co-author of a recent paper online in the Chinese Science Bulletin that described the discovery.”The preservation of the new cranium is excellent, with only minimal post-depositional distortion,” Jablonski said. “This is important because all previously discovered adult crania of the species to which it is assigned, Lufengpithecus lufengensis, were badly crushed and distorted during the fossilization process. In living ape species, cranial anatomy in individuals at the same stage of development as the new fossil cranium already show a close resemblance to those of adults.”Therefore, the new cranium, despite being from a juvenile, gives researchers the best look at the cranial anatomy of Lufengpithecus lufengensis.”Partly because of where and when Lufengpithecus lived, it is considered by most to be in the lineage of the extant orangutan, now confined to Southeast Asia but known from the late Pleistocene of southern China as well,” Jablonski said.However, the researchers noted the cranium shows little resemblance to those of living orangutans, and in particular, shows none of what are considered to be key diagnostic features of orangutan crania. Lufengpithecus therefore appears to represent a late surviving lineage of Eurasian apes, but with no certain affinities yet clear.The survival of this lineage is not entirely surprising since southern China was less affected by climatic deterioration during the later Miocene that resulted in the extinction of many ape species throughout the rest of Eurasia. The researchers are hopeful that further excavations will produce the remains of adult individuals, which will allow them to better assess the relationships among members of this lineage as well as the relationships of this lineage to other fossil and extant apes.

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Obesity and diabetes risk: One in four has alarmingly few intestinal bacteria

Aug. 28, 2013 — International ground-breaking research with participation of Danish investigators from University of Copenhagen shows that one in four Danes has serious problems with the trillion of bacteria living in their intestines. The problems appear to be associated with increased risk of obesity and diabetes. Published in Nature, the research fortunately points to potential solutions.All people have trillions of bacteria living in their intestines. If you place them on a scale, they weigh around 1.5 kg. Previously, a major part of these ‘blind passengers’ were unknown, as they are difficult or impossible to grow in laboratories. But over the past five years, an EU-funded research team, MetaHIT, coordinated by Professor S. Dusko Ehrlich at the INRA Research Centre of Jouy-en-Josas, France and with experts from Europe and China have used advanced DNA analysis and bioinformatics methods to map human intestinal bacteria.”The genetic analysis of intestinal bacteria from 292 Danes shows that about a quarter of us have up to 40% less gut bacteria genes and correspondingly fewer bacteria than average. Not only has this quarter fewer intestinal bacteria, but they also have reduced bacterial diversity and they harbour more bacteria causing a low-grade inflammation of the body. This is a representative study sample, and the study results can therefore be generalised to people in the Western world,” says Oluf Pedersen, Professor and Scientific Director at the Faculty of Health and Medical Sciences, University of Copenhagen.Oluf Pedersen and Professor Torben Hansen have headed the Danish part of the MetaHIT project, and the findings are reported in scientific journal Nature.The gut is like a rainforestOluf Pedersen compares the human gut and its bacteria with a tropical rainforest. …

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Not the end of the world: Why Earth’s greatest mass extinction was the making of modern mammals

Aug. 28, 2013 — The ancient closest relatives of mammals — the cynodont therapsids — not only survived the greatest mass extinction of all time, 252 million years ago, but thrived in the aftermath, according to new research published today (28th August).The first mammals arose in the Triassic period, more than 225 million years ago. These early fur balls include small shrew-like animals such as Morganucodon from England, Megazostrodon from South Africa and Bienotherium from China.They had differentiated teeth (incisors, canines, molars) and large brains and were probably warm-blooded and covered in fur — all characteristics that stand them apart from their reptile ancestors, and which contribute to their huge success today.However, new research suggests that this array of unique features arose gradually over a long span of time, and that the first mammals may have arisen as a result of the end-Permian mass extinction — which wiped out 90 per cent of marine organisms and 70 per cent of terrestrial species.The research was conducted by the University of Lincoln, UK, the National Museum in Bloemfontein, South Africa, and the University of Bristol, UK, and has been published today in Proceedings of the Royal Society B.Lead author Dr Marcello Ruta, evolutionary palaeobiologist from the University of Lincoln’s School of Life Sciences, said: “Mass extinctions are seen as entirely negative. However, in this case, cynodont therapsids, which included a very small number of species before the extinction, really took off afterwards and were able to adapt to fill many different niches in the Triassic — from carnivores to herbivores.”Co-author Dr Jennifer Botha-Brink of the National Museum in Bloemfontein, South Africa, said: “During the Triassic, the cynodonts split into two groups, the cynognathians and the probainognathians. The first were mainly plant-eaters, the second mainly flesh-eaters and the two groups seemed to rise and fall at random — first one expanding, and then the other. In the end, the probainognathians became the most diverse and most varied in adaptations, and they gave rise to the first mammals some 25 million years after the mass extinction.”Co-author Professor Michael Benton, of the University of Bristol, UK, added: “We saw that when a major group, such as cynodonts, diversifies, it is the body shape or range of adaptations that expands first. The diversity, or number of species, rises after all the morphologies available to the group have been tried out.”The researchers concluded that cynodont diversity rose steadily during the recovery of life following the mass extinction, with their range of form rising rapidly at first before hitting a plateau. This suggests there is no particular difference in morphological diversity between the very first mammals and their immediate cynodont predecessors.

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New risk model sheds light on arsenic risk in China’s groundwater

Aug. 22, 2013 — Arsenic-laden groundwater used for cooking and drinking could pose a risk to the health of almost 20 million people across China. This is shown by a study carried out by Eawag scientists in collaboration with Chinese colleagues and published today in Science. The estimates are based on a risk model incorporating geological and hydrological data, as well as measurements of arsenic in wells. The study is being adopted by the authorities in the national groundwater monitoring programme.Since the 1960s, it has been known that groundwater resources in certain provinces of China are contaminated with arsenic. Estimates of the numbers of affected people have risen year by year. In the most recent survey — conducted by the Chinese Ministry of Health between 2001 and 2005 — more than 20,000 (5%) of the 445,000 wells tested showed arsenic concentrations higher than 50 µg/L. According to official estimates, almost 6 million people consume drinking water with an arsenic content of more than 50 µg/L and almost 15 million are exposed to concentrations exceeding 10 µg/L (the guideline value recommended by the WHO).Given the sheer size of China and the time and expense involved in testing for arsenic contamination, several more decades would probably be required to screen all of the millions of groundwater wells. Accordingly, a group of researchers from Eawag and the China Medical University in Shenyang developed a statistical risk model making use of existing data on geology, soil characteristics and topographic features. This model was calibrated using available arsenic measurements. …

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Future flood losses in major coastal cities: Costly projections

Aug. 19, 2013 — Climate change combined with rapid population increases, economic growth and land subsidence could lead to a more than nine-fold increase in the global risk of floods in large port cities between now and 2050.”Future Flood Losses in Major Coastal Cities,” published in Nature Climate Change, is part of an ongoing project by the Organisation for Economic Co-operation and Development (OECD) to explore the policy implications of flood risks due to climate change and economic development. This study builds on past OECD work which ranked global port cities on the basis of current and future exposure, where exposure is the maximum number of people or assets that could be affected by a flood.The authors estimate present and future flood losses — or the global cost of flooding — in 136 of the world’s largest coastal cities, taking into account existing coastal protections. Average global flood losses in 2005, estimated at about US$6 billion per year, could increase to US$52 billion by 2050 with projected socio-economic change alone.The cities ranked most ‘at risk’ today, as measured by annual average losses due to floods, span developed and developing countries: Guangzhou, Miami, New York, New Orleans, Mumbai, Nagoya, Tampa-St. Petersburg, Boston, Shenzen, Osaka-Kobe, and Vancouver. The countries at greatest risk from coastal city flooding include the United States and China. Due to their high wealth and low protection level, three American cities (Miami, New York City and New Orleans) are responsible for 31 per cent of the losses across the 136 cities. Adding Guangzhou, the four top cities explain 43 per cent of global losses as of 2005.Total dollar cost is one way to assess risk. Another is to look at annual losses as a percentage of a city’s wealth, a proxy for local vulnerability. Using this measure, Guangzhou, China; Guayaquil, Ecuador; Ho Chi Minh City, Vietnam; and Abidjan, Ivory Coast are among the most vulnerable.To estimate the impact of future climate change the study assumes that mean sea-level, including contributions from melting ice sheets, will rise 0.2-0.4 meters by 2050. …

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