Powerful artificial muscles made from fishing line and sewing thread

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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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#Alzheimer, #Australia, #China, #Health, #Korea, #South, #Turkey, #Windows

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

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

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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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#African, #Agriculture, #Alzheimer, #China, #Dna, #Europe, #Genetic, #Genetics, #Germany, #London, #Result, #Study

Research examines acupuncture needle quality

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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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#Agriculture, #China, #Health, #Korea, #Materials, #Physical, #Professor, #School, #Science, #Western

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

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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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#Alternative-Medicine, #Cancer, #China, #Device, #Izo, #Physics, #Pregnancy, #Science, #Story, #Tft

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

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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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#Alternative-Medicine, #Animal, #China, #Marine, #Permian, #Science, #Species, #Traps