Carbon loss from soil accelerating climate change

Research published in Science today found that increased levels of carbon dioxide in the atmosphere cause soil microbes to produce more carbon dioxide, accelerating climate change.Two Northern Arizona University researchers led the study, which challenges previous understanding about how carbon accumulates in soil. Increased levels of CO2 accelerate plant growth, which causes more absorption of CO2 through photosynthesis.Until now, the accepted belief was that carbon is then stored in wood and soil for a long time, slowing climate change. Yet this new research suggests that the extra carbon provides fuel to microorganisms in the soil whose byproducts (such as CO2) are released into the atmosphere, contributing to climate change.”Our findings mean that nature is not as efficient in slowing global warming as we previously thought,” said Kees Jan van Groenigen, research fellow at the Center for Ecosystem Science and Society at NAU and lead author of the study. “By overlooking this effect of increased CO2 on soil microbes, models used by the Intergovernmental Panel on Climate Change may have overestimated the potential of soil to store carbon and mitigate the greenhouse effect.”In order to better understand how soil microbes respond to the changing atmosphere, the study’s authors utilized statistical techniques that compare data to models and test for general patterns across studies. They analyzed published results from 53 different experiments in forests, grasslands and agricultural fields around the world. These experiments all measured how extra CO2 in the atmosphere affects plant growth, microbial production of carbon dioxide, and the total amount of soil carbon at the end of the experiment.”We’ve long thought soils to be a stable, safe place to store carbon, but our results show soil carbon is not as stable as we previously thought,” said Bruce Hungate, director of the Center for Ecosystem Science and Society at NAU and study author. “We should not be complacent about continued subsidies from nature in slowing climate change.”Story Source:The above story is based on materials provided by Northern Arizona University. Note: Materials may be edited for content and length.

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Braking system for immune responses

For the first time, researchers have identified a receptor on human cells that specifically recognizes crystals. It is found on immune cells and binds uric acid crystals, which trigger gout but also control immune responses. The team, led by researchers from Technische Universitt Mnchen (TUM)’s Klinikum rechts der Isar hospital have published their findings in the Immunity journal.The surface of immune system cells is home to a number of receptors which are able to detect pathogens. As soon as these receptors are activated, inflammation occurs and the body’s defense mechanisms kick in. Immune cells also have receptors that regulate or even suppress immunological responses to prevent damage to individual cells.There are other immune receptors that recognize endogenous substances that are released when tissue damage or cell death occurs. As such, the organism can defend itself even in cases where the damage caused by the pathogen, but not the pathogen itself, is detected.With the discovery of the surface molecule Clec12a from the family of C-type lectin receptors, the team led by Prof. Jrgen Ruland of Klinikum rechts der Isar have found the first known immune receptor for uric acid crystals. Uric acid is a break-down product of nucleic acids like DNA in response to cell damage. Whenever a large number of cells die, for example when a tumor is being medically treated or during an infection, the uric acid becomes more concentrated and the molecules crystallize.Immune responses have to be regulatedUric acid crystals also form when tissue is damaged and they boost the immune response. However, Clec12a limits the immune response instead of increasing it. …

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Genetically modified spuds beat blight

In a three-year GM research trial, scientists boosted resistance of potatoes to late blight, their most important disease, without deploying fungicides.The findings, funded by the Biotechnology and Biological Sciences Research Council and The Gatsby Foundation, will be published in Philosophical Transactions of the Royal Society B on 17 February.In 2012, the third year of the trial, the potatoes experienced ideal conditions for late blight. The scientists did not inoculate any plants but waited for races circulating in the UK to blow in.Non-transgenic Desiree plants were 100% infected by early August while all GM plants remained fully resistant to the end of the experiment. There was also a difference in yield, with tubers from each block of 16 plants weighing 6-13 kg while the non-GM tubers weighed 1.6-5 kg per block.The trial was conducted with Desiree potatoes to address the challenge of building resistance to blight in potato varieties with popular consumer and processing characteristics.The introduced gene, from a South American wild relative of potato, triggers the plant’s natural defense mechanisms by enabling it to recognize the pathogen. Cultivated potatoes possess around 750 resistance genes but in most varieties, late blight is able to elude them.”Breeding from wild relatives is laborious and slow and by the time a gene is successfully introduced into a cultivated variety, the late blight pathogen may already have evolved the ability to overcome it,” said Professor Jonathan Jones from The Sainsbury Laboratory.”With new insights into both the pathogen and its potato host, we can use GM technology to tip the evolutionary balance in favor of potatoes and against late blight.”In northern Europe, farmers typically spray a potato crop 10-15 times, or up to 25 times in a bad year. Scientists hope to replace chemical control with genetic control, though farmers might be advised to spray even resistant varieties at the end of a season, depending on conditions.The Sainsbury Laboratory is continuing to identify multiple blight resistance genes that will difficult for blight to simultaneously overcome. Their research will allow resistance genes to be prioritized that will be more difficult for the pathogen to evade.In a new BBSRC-funded industrial partnership award with American company Simplot and the James Hutton Institute, the TSL researchers will continue to identify and experiment with multiple resistance genes. By combining understanding of resistance genes with knowledge of the pathogen, they hope to develop Desiree and Maris Piper varieties that can completely thwart attacks from late blight.Story Source:The above story is based on materials provided by Norwich BioScience Institutes. Note: Materials may be edited for content and length.

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New, inexpensive production materials boost promise of hydrogen fuel

Generating electricity is not the only way to turn sunlight into energy we can use on demand. The sun can also drive reactions to create chemical fuels, such as hydrogen, that can in turn power cars, trucks and trains.The trouble with solar fuel production is the cost of producing the sun-capturing semiconductors and the catalysts to generate fuel. The most efficient materials are far too expensive to produce fuel at a price that can compete with gasoline.”In order to make commercially viable devices for solar fuel production, the material and the processing costs should be reduced significantly while achieving a high solar-to-fuel conversion efficiency,” says Kyoung-Shin Choi, a chemistry professor at the University of Wisconsin-Madison.In a study published last week in the journal Science, Choi and postdoctoral researcher Tae Woo Kim combined cheap, oxide-based materials to split water into hydrogen and oxygen gases using solar energy with a solar-to-hydrogen conversion efficiency of 1.7 percent, the highest reported for any oxide-based photoelectrode system.Choi created solar cells from bismuth vanadate using electrodeposition — the same process employed to make gold-plated jewelry or surface-coat car bodies — to boost the compound’s surface area to a remarkable 32 square meters for each gram.”Without fancy equipment, high temperature or high pressure, we made a nanoporous semiconductor of very tiny particles that have a high surface area,” says Choi, whose work is supported by the National Science Foundation. “More surface area means more contact area with water, and, therefore, more efficient water splitting.”Bismuth vanadate needs a hand in speeding the reaction that produces fuel, and that’s where the paired catalysts come in.While there are many research groups working on the development of photoelectric semiconductors, and many working on the development of water-splitting catalysts, according to Choi, the semiconductor-catalyst junction gets relatively little attention.”The problem is, in the end you have to put them together,” she says. “Even if you have the best semiconductor in the world and the best catalyst in the world, their overall efficiency can be limited by the semiconductor-catalyst interface.”Choi and Kim exploited a pair of cheap and somewhat flawed catalysts — iron oxide and nickel oxide — by stacking them on the bismuth vanadate to take advantage of their relative strengths.”Since no one catalyst can make a good interface with both the semiconductor and the water that is our reactant, we choose to split that work into two parts,” Choi says. “The iron oxide makes a good junction with bismuth vanadate, and the nickel oxide makes a good catalytic interface with water. So we use them together.”The dual-layer catalyst design enabled simultaneous optimization of semiconductor-catalyst junction and catalyst-water junction.”Combining this cheap catalyst duo with our nanoporous high surface area semiconductor electrode resulted in the construction of an inexpensive all oxide-based photoelectrode system with a record high efficiency,” Choi says.She expects the basic work done to prove the efficiency enhancement by nanoporous bismuth vanadate electrode and dual catalyst layers will provide labs around the world with fodder for leaps forward.”Other researchers studying different types of semiconductors or different types of catalysts can start to use this approach to identify which combinations of materials can be even more efficient,” says Choi, whose lab is already tweaking their design. “Which some engineering, the efficiency we achieved could be further improved very fast.”Story Source:The above story is based on materials provided by University of Wisconsin-Madison. The original article was written by Chris Barncard. Note: Materials may be edited for content and length.

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Substance in photosynthesis was in play in ancient, methane-producing microbes

An international team of researchers led by scientists at Virginia Tech and the University of California, Berkeley has discovered that a process that turns on photosynthesis in plants likely developed on Earth in ancient microbes 2.5 billion years ago, long before oxygen became available.The research offers new perspective on evolutionary biology, microbiology, and the production of natural gas, and may shed light on climate change, agriculture, and human health.”By looking at this one mechanism that was not previously studied, we will be able to develop new basic information that potentially has broad impact on contemporary issues ranging from climate change to obesity,” said Biswarup Mukhopadhyay, an associate professor of biochemistry at the Virginia Tech College of Agriculture and Life Sciences, and the senior author of the study. He is also a faculty member at the Virginia Bioinformatics Institute. Plant and microbial biology professor emeritus Bob B. Buchanan co-led the research and co-authored the paper.The findings were described this week in an early online edition of the Proceedings of the National Academy of Sciences.This research concerns methane-forming archaea, a group of microbes known as methanogens, which live in areas where oxygen is absent. Methane is the main component of natural gas and a potent greenhouse gas.”This innovative work demonstrates the importance of a new global regulatory system in methanogens,” said William Whitman, a professor of microbiology at the University of Georgia who is familiar with the study, but not connected to it. “Understanding this system will provide the tools to use these economically important microorganisms better.”Methanogens play a key role in carbon cycling. When plants die, some of their biomass is trapped in areas that are devoid of oxygen, such as the bottom of lakes.Methanogens help convert the residual biological material to methane, which other organisms convert to carbon dioxide — a product that can be used by plants.This natural process for producing methane forms the basis for treating municipal and industrial wastes, helps reduce pollution, and provides methane for fuel. The same process allows natural gas production from agricultural residues, a renewable resource.Methanogens also play an important role in agriculture and human health. They live in the digestive systems of cattle and sheep where they facilitate the digestion of feed consumed in the diet.Efforts to control methanogens in specific ways may improve feed utilization and enhance the production of meat and milk, researchers say.Methanogens are additionally a factor in human nutrition. The organisms live in the large intestine, where they enhance the breakdown of food. …

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World ocean systems undermined by climate change by 2100

Oct. 15, 2013 — An ambitious new study describes the full chain of events by which ocean biogeochemical changes triggered by humanmade greenhouse gas emissions may cascade through marine habitats and organisms, penetrating to the deep ocean and eventually influencing humans.Previous analyses have focused mainly on ocean warming and acidification, considerably underestimating the biological and social consequences of climate change. Factoring in predictable synergistic changes such as the depletion of dissolved oxygen in seawater and a decline in productivity of ocean ecosystems, the new study shows that no corner of the world ocean will be untouched by climate change by 2100.”When you look at the world ocean, there are few places that will be free of changes; most will suffer the simultaneous effects of warming, acidification, and reductions in oxygen and productivity,” said lead author Camilo Mora, assistant professor at the Department of Geography in the College of Social Sciences at the University of Hawai’i at Mānoa (UH Mānoa). “The consequences of these co-occurring changes are massive — everything from species survival, to abundance, to range size, to body size, to species richness, to ecosystem functioning are affected by changes in ocean biogeochemistry.”The human ramifications of these changes are likely to be massive and disruptive. Food chains, fishing, and tourism could all be impacted. The study shows that some 470 to 870 million of the world’s poorest people rely on the ocean for food, jobs, and revenues, and live in countries where ocean goods and services could be compromised by multiple ocean biogeochemical changes.Mora and Craig Smith with UH Mānoa’s School of Ocean and Earth Science and Technology (SOEST) worked with a 28-person international collaboration of climate modelers, biogeochemists, oceanographers, and social scientists to develop the study, which is due for publication October 15 in the scientific journal PLOS Biology.The researchers used the most recent and robust models of projected climate change developed for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) to inform their analysis. They quantified the extent of co-occurrence of changes in temperature, pH, oxygen, and primary productivity based on two scenarios: a business-as-usual scenario wherein atmospheric CO2 concentrations could reach 900 ppm by 2100, and an alternative scenario under which concentrations only reach 550 ppm by 2100 (representing a concerted, rapid CO2 mitigation effort, beginning today).They discovered that most of the world’s ocean surface will be simultaneously impacted by varying intensities of ocean warming, acidification, oxygen depletion, or shortfalls in productivity. Only a very small fraction of the oceans, mostly in polar regions, will face the opposing effects of increases in oxygen or productivity, and nowhere will there be cooling or pH increase.”Even the seemingly positive changes at high latitudes are not necessary beneficial. Invasive species have been immigrating to these areas due to changing ocean conditions and will threaten the local species and the humans who depend on them,” said co-author Chih-Lin Wei, a postdoctoral fellow at Ocean Science Centre, Memorial University of Newfoundland, Canada.The researchers assembled global distribution maps of 32 marine habitats and biodiversity hotspots to assess their potential vulnerability to the changes. As a final step, they used available data on human dependency on ocean goods and services and social adaptability to estimate the vulnerability of coastal populations to the projected ocean biogeochemical changes.”Other studies have looked at small-scale impacts, but this is the first time that we’ve been able to look the entire world ocean and how co-occurring stressors will differentially impact the earth’s diverse habitats and people,” said co-author Andrew Thurber, a postdoctoral fellow at Oregon State University. …

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Bacteria supplemented their diet to clean up after Deep Water Horizon oil

Aug. 29, 2013 — Bacteria living in the Gulf of Mexico beaches were able to ‘eat up’ the contamination from the Deep Water Horizon oil spill by supplementing their diet with nitrogen, delegates at the Goldschmidt conference will be told today, Friday 30th August.Professor Joel Kostka will tell geochemists gathered in Florence for the conference that detailed genetic analysis showed some of the bacteria thrived on a diet of oil because they were able to fix nitrogen from the air. The research — the first to use next generation sequencing technologies to dig into the detail of how the native beach microbes are metabolising the oil over time — could open the door to much more sophisticated clean up techniques.”Oil is a natural product, made of decayed plants and animals, and so is similar to the normal food sources for these bacteria.” explains Professor Kostka, a microbiologist from Georgia Institute of Technology in Atlanta. “But because oil is low in nutrients such as nitrogen, this can limit how fast the bacteria grow and how quickly they are able to break down the oil. Our analysis showed that some bacteria are able to solve this problem themselves — by getting their own nitrogen from the air.”Professor Kostka worked with Professor Markus Huettel, a biogeochemist from Florida State University, to take more than 500 samples over two years from Pensacola beach in the Gulf of Mexico, starting when the Deep Water Horizon oil slick first came ashore in June 2010. By analysing every gene of every bacteria in the sample, they were able to see which bacteria were present and how they responded as the conditions on the beach changed.The researchers looked at the prevalence of genes which encode for different types of activity — such as nitrogen fixing or phosphorus uptake — to identify exactly how the bacteria were degrading the oil.”By understanding how the oil is degraded by microbes, which microbes do the work, and the impact of the surrounding environmental conditions, we can develop ways to intervene to support the natural clean-up process,” says Professor Kostka. “However, we need to do this in a very measured and targeted way, to avoid long-term, unintended damage to the ecosystem. For example, in the past, nitrogen fertiliser has been sprayed onto contaminated beaches to speed up the work of the bacteria. Our analysis shows that, where bacteria can get this nitrogen naturally, such drastic intervention may not be necessary.”The genetic analysis carried out by Professor Kostka and his colleague Konstantinos Konstantinidis at Georgia Tech can show exactly how the oil-degrading bacteria are working at each part of an affected coastline, making it possible to identify which beaches are most effective at self-cleaning and target mitigation efforts — such as offshore booms — at the most vulnerable areas.But not all the bacteria thrived on a diet of oil. Professor Kostka’s research showed that some bacteria which play an important role in the ecosystem of the beaches experienced a sharp decline following the contamination in June 2010.”There’s a tendency to focus on the short-term, visible effects of an oil spill on the beach and assume that once the beach looks ‘clean’ then all is back to normal,” he says. …

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Hydrogen fuel from sunlight

Aug. 29, 2013 — In the search for clean, green sustainable energy sources to meet human needs for generations to come, perhaps no technology matches the ultimate potential of artificial photosynthesis. Bionic leaves that could produce energy-dense fuels from nothing more than sunlight, water and atmosphere-warming carbon dioxide, with no byproducts other than oxygen, represent an ideal alternative to fossil fuels but also pose numerous scientific challenges. A major step toward meeting at least one of these challenges has been achieved by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) working at the Joint Center for Artificial Photosynthesis (JCAP).”We’ve developed a method by which molecular hydrogen-producing catalysts can be interfaced with a semiconductor that absorbs visible light,” says Gary Moore, a chemist with Berkeley Lab’s Physical Biosciences Division and principal investigator for JCAP. “Our experimental results indicate that the catalyst and the light-absorber are interfaced structurally as well as functionally.”Moore is the corresponding author, along with Junko Yano and Ian Sharp, who also hold joint appointments with Berkeley Lab and JCAP, of a paper describing this research in the Journal of the American Chemical Society (JACS). The article is titled “Photofunctional Construct That Interfaces Molecular Cobalt-Based Catalysts for H2 Production to a Visible-Light-Absorbing Semiconductor.” Co-authors are Alexandra Krawicz, Jinhui Yang and Eitan Anzenberg.Earth receives more energy in one hour’s worth of sunlight than all of humanity uses in an entire year. Through the process of photosynthesis, green plants harness solar energy to split molecules of water into oxygen, hydrogen ions (protons) and free electrons. The oxygen is released as waste and the protons and electrons are used to convert carbon dioxide into the carbohydrate sugars that plants use for energy. Scientists aim to mimic the concept but improve upon the actual process.JCAP, which has a northern branch in Berkeley and a southern branch on the campus of the California Institute of Technology (Caltech), was established in 2010 by DOE as an Energy Innovation Hub. …

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Cancer researchers discover how BRCA mutation starts breast, ovarian cancers

July 15, 2013 — Scientists led by Drs. Mona Gauthier and Tak Mak at The Campbell Family Institute for Breast Cancer Research at the Princess Margaret Cancer Centre have solved a key piece in the puzzle of how BRCA1 gene mutations specifically predispose women to breast and ovarian cancers.The answer, says Dr. Mak in research published today in the Journal of Experimental Medicine, is found in the way estrogen rushes in to “rescue” cells whose healthy functioning has been altered by oxidative stress, a well-established factor in cancer development. Without estrogen, these damaged cells would die a natural death and not threaten the host in the long run, but with estrogen, these cells not only survive, but thrive and develop breast and ovarian cancers. In Canada, about 1,000 women die from BRCA1-related cancers every year.The research published today illuminates the interplay between the tumour suppressor gene BRCA1 and a master regulator — Nrf2 — that governs the antioxidant response in cells. In healthy cells of all tissues, BRCA1 normally repairs damaged DNA in partnership with Nrf2, and so the cells are protected against oxidative stress. However, when the BRCA1 gene is mutated, it loses its ability to repair DNA and can no longer partner with Nrf2, shutting off its antioxidative function. In most tissues, the resulting oxidative stress kills the cells that have lost BRCA1 function. However, in breast and ovary, the estrogen present in these tissues can swoop in to rescue BRCA1-deficient cells by triggering a partial turn-on of Nrf2. These unhealthy cells gain just enough resistance to oxidative stress to keep them alive and growing. …

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Delayed puberty: First estrogen receptor mutation found in a young woman

July 11, 2013 — A receptor mutation that essentially blocks estrogen’s action has been identified for the first time in a female, researchers report.The 18-year-old wasn’t experiencing breast development or menstruation, classic symptoms of too little estrogen, the usual cause of delayed puberty. Subsequent studies revealed instead sky-high levels of the sex hormone in her blood, said Dr. Lawrence C. Layman, Chief of the Section of Reproductive Endocrinology, Infertility and Genetics at the Medical College of Georgia at Georgia Regents University.”Her body totally ignores estrogen,” Layman said. “Even at levels that are 10 to 15 times normal, it has no effect.” In fact, in laboratory studies, 240 times the normal level was required to get a response out of the receptor.There are two confirmed estrogen receptors, and genetic testing subsequently determined she had a mutation in estrogen receptor-α, which is essential to reproduction and bone health, researchers report in the New England Journal of Medicine. Estrogen levels in her blood were comparable to those of a mouse whose estrogen receptor-α gene has been deleted.Interestingly the first mutation in this receptor was reported nearly 20 years earlier in the NEJM in a 28-year old man with knock-knees and signs of insulin resistance. Studies showed his testosterone levels were normal and, although his estrogen and related hormone levels were high, he also had essentially no response to estrogen. The research team, led by Children’s Hospital Medical Center in Cincinnati, found the estrogen receptor defect, concluding that estrogen is important to bone health in men as well as women.The estrogen receptor-α mutation found in the female is slightly different but also results in profound estrogen resistance in women, said Layman, the new study’s corresponding author. The major known impacts of estrogen in women are enabling reproduction, breast development, and bone health.While generally healthy, the young woman sought medical help due to her lack of breast development and menstruation as well as lingering, lower-abdominal pain. Studies by Dr. …

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Bacteria communicate to help each other resist antibiotics

July 4, 2013 — New research from Western University unravels a novel means of communication that allows bacteria such as Burkholderia cenocepacia (B. cenocepacia) to resist antibiotic treatment. B. cenocepacia is an environmental bacterium that causes devastating infections in patients with cystic fibrosis (CF) or with compromised immune systems.Dr. Miguel Valvano and first author Omar El-Halfawy, PhD candidate, show that the more antibiotic resistant cells within a bacterial population produce and share small molecules with less resistant cells, making them more resistant to antibiotic killing. These small molecules, which are derived from modified amino acids (the building blocks used to make proteins), protect not only the more sensitive cells of B. cenocepacia but also other bacteria including a highly prevalent CF pathogen, Pseudomonas aeruginosa, and E. coli. The research is published in PLOS ONE.”These findings reveal a new mechanism of antimicrobial resistance based on chemical communication among bacterial cells by small molecules that protect against the effect of antibiotics,” says Dr. Valvano, adjunct professor in the Department of Microbiology and Immunology at Western’s Schulich School of Medicine & Dentistry, currently a Professor and Chair at Queen’s University Belfast. …

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Protocells may have formed in a salty soup

July 2, 2013 — The first cell may have originated in a salty soup in which large biomolecules cluster spontaneously to form a protocell, chemists at Radboud University Nijmegen discovered.The research is published in the Proceedings of the National Academy of Sciences.How did the first cell originate in evolution? It is a chicken or the egg causality dilemma: a cell doesn’t function without a cell wall, but how does the cell wall form if there is no cell? Research by chemist Wilhelm Huck, professor at Radboud University Nijmegen, suggests that the cell came first.In a solution containing the biomolecules that are normally locked in a cell (like DNA, RNA, enzymes, proteins) these large biomolecules clustered together spontaneously when the salt concentration was increased. This indicates that a cell wall is not a prerequisite for a cell-like structure .Huck thinks the macro molecules in our cells evolved to do their work while packed closely together. By using tiny droplets, he explores how this works exactly. “When biomolecules are packed together, we expect reactions to proceed much faster. They perform their chemistry much more efficiently. In this study, we measure a fifty-fold increase in the DNA transcription rate.”A working cell is more than the sum of its parts. “A functioning cell must be entirely correct at once, in all its complexity,” said Huck. “We are now closer to building a synthetic cell than anyone ever before us.”

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Non-invasive brain stimulation helps stroke patients gain prolonged language recovery

July 2, 2013 — A new study details of a technique developed by researchers to improve language function in stroke patients with chronic speech-language impairment. The study is published in the Journal of Visualized Experiments (JoVE).Strokes occur when a brain clot blocks blood flow in parts of the brain, essentially starving groups of neurons of oxygen, which is necessary for normal function. Nearly 130,000 of the 795,000 strokes Americans suffer annually result in death, accounting for roughly 5% of deaths in the U.S. The remaining 665,000 stroke patients suffer a wide variety of side effects ranging from complete loss of motor function to loss of speech to a catatonic state. Because of the horrific nature of these cerebrovascular events and their consequences, many clinical researchers focus on prevention, rehabilitation and restoration of function for stroke victims.A technique developed through these efforts utilizes transcranial magnetic stimulation (TMS) to improve language function in stroke patients with chronic aphasia. Patients who have undergone this procedure have previously reached a plateau in their ability to produce fluent language, despite signs of understanding and frustration at their inability to communicate.”The heart of our work is to use non-invasive brain stimulation… to modulate cortical networks that we think are in flux. We think that those circuits in the brain do remodel and that we can tweak them further using non-invasive stimulation,” explains Roy Hamilton, M.D., the co-director of the Laboratory for Cognition and Neural Stimulation at the University of Pennsylvania Medical School. He continues, “For most people the left hemisphere plays a dominant role in our language capacity. The brain does have the capacity to reorganize itself and rework some of the network and geography that represents specific cognitive skills.”Transcranial magnetic stimulation was first successfully performed in 1985 by Anthony Barker and his colleagues in Sheffield, UK. The technique takes advantage of an aspect of physics derived from the Biot-Savart Law, which states that a current running through a wire generates a magnetic field. …

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Social capabilities of performing multiple-action sequences

June 26, 2013 — The day of the big barbecue arrives and it’s time to fire up the grill. But rather than toss the hamburgers and hotdogs haphazardly onto the grate, you wait for the heat to reach an optimal temperature, and then neatly lay them out in their apportioned areas according to size and cooking times. Meanwhile, your friend is preparing the beverages. Cups are grabbed face down from the stack, turned over, and — using the other hand — filled with ice.While these tasks — like countless, everyday actions — may seem trivial at first glance, they are actually fairly complex, according to Robrecht van der Wel, an assistant professor of psychology at Rutgers-Camden. “For instance, the observation that you grab a glass differently when you are filling a beverage than when you are stacking glasses suggests that you are thinking about the goal that you want to achieve,” he says. “How do you manipulate the glass? How do you coordinate your actions so that the liquid goes into the cup? These kinds of actions are not just our only way to accomplish our intentions, but they reveal our intentions and mental states as well.”van der Wel and his research partners, Marlene Meyer and Sabine Hunnius, turned their attention to how action planning generalizes to collaborative actions performed with others in a study, titled Higher-order planning for individual and joint object manipulations, published recently in Experimental Brain Research.According to van der Wel, the researchers were especially interested in determining whether people’s actions exhibit certain social capabilities when performing multiple-action sequences in concert with a partner. “It is a pretty astonishing ability that we, as people, are able to plan and coordinate our actions with others,” says van der Wel. “If people plan ahead for themselves, what happens if they are now in a task where their action might influence another person’s comfort? …

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Feeling stressed? Oxytocin could help you reach out to others for support

June 25, 2013 — The next time someone snubs you at a party and you think hiding is the solution to escape your feelings of rejection, think again. Scientists have shown that reaching out to other people during a stressful event is an effective way to improve your mood, and researchers at Concordia University suggest that the hormone oxytocin may help you accomplish just that.Mark Ellenbogen and Christopher Cardoso, researchers in Concordia’s Centre for Research in Human Development are taking a closer look at oxytocin, a hormone traditionally studied for its role in childbirth and breastfeeding, and more recently for its effect on social behaviour. Their latest study, published in the peer-reviewed journal Psychoneuroendocrinology, shows that oxytocin can increase a person’s trust in others following social rejection.Explains Ellenbogen, “that means that instead of the traditional ‘fight or flight’ response to social conflict where people get revved up to respond to a challenge or run away from it, oxytocin may promote the ‘tend and befriend’ response where people reach out to others for support after a stressful event. That can, in turn, strengthen social bonds and may be a healthier way to cope.”In a double-blind experiment, 100 students were administered either oxytocin or a placebo via a nasal spray, then subjected to social rejection. In a conversation that was staged to simulate real life, researchers posing as students disagreed with, interrupted and ignored the unsuspecting participants. Using mood and personality questionnaires, the data showed that participants who were particularly distressed after being snubbed by the researchers reported greater trust in other people if they sniffed oxytocin prior to the event, but not if they sniffed the placebo. In contrast, oxytocin had no effect on trust in those who were not emotionally affected by social rejection.Cardoso, who is a doctoral student in the Department of Psychology, says that studying oxytocin may provide future options for those who suffer from mental health conditions characterized by high levels of stress and low levels of social support, like depression. “If someone is feeling very distressed, oxytocin could promote social support seeking, and that may be especially helpful to those individuals,” he says, noting that people with depression tend to naturally withdraw even though reaching out to social support systems can alleviate depression and facilitate recovery.For Ellenbogen, who holds a Canada Research Chair in Developmental Psychopathology, the contribution of stress the development of mood disorders like depression and bipolar disorder has long been a research focus. “I’m concerned with the biological underpinnings of stress, particularly interpersonal stress, which is thought to be a strong predictor of these mental disorders. So, oxytocin is a natural fit with my interests,” says Ellenbogen. …

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Too green to be true? Highly effective method for converting CO2 into methanol

June 20, 2013 — Université Laval researchers have developed a highly effective method for converting CO2 into methanol, which can be used as a low-emissions fuel for vehicles. The team led by Professor Frédéric-Georges Fontaine presents the details of this discovery in the latest issue of the Journal of the American Chemical Society.Researchers have been looking for a way to convert carbon dioxide into methanol in a single step using energy-efficient processes for years. “In the presence of oxygen, methanol combustion produces CO2 and water,” explained Professor Fontaine. “Chemists are looking for catalysts that would yield the opposite reaction. That would allow us to slash greenhouse gas emissions by synthesizing a fuel that would reduce our dependence on fossil fuels.”The catalyst developed by Frédéric-Georges Fontaine and his team is made of two chemical groups. The first is borane, a compound of boron, carbon, and hydrogen. The second, phosphine, is made up of phosphorus, carbon, and hydrogen. “Unlike most catalysts developed thus far to convert CO2 into methanol, ours contains no metal, which reduces both the costs and toxic hazard of the catalyst,” added the chemistry professor at the Faculty of Science and Engineering.CO2 to methanol catalysis requires a source of hydrogen and chemical energy. The researchers had the idea of using a compound called hydroborane (BH3), and the results have been spectacular. The reaction achieved is two times more effective than the best catalyst known — and it produces little waste. …

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Metamorphosis of moon’s water ice explained

June 19, 2013 — Using data gathered by NASA’s Lunar Reconnaissance Orbiter (LRO) mission, scientists believe they have solved a mystery from one of the solar system’s coldest regions — a permanently shadowed crater on the moon. They have explained how energetic particles penetrating lunar soil can create molecular hydrogen from water ice. The finding provides insight into how radiation can change the chemistry of water ice throughout the solar system.Space scientists from the University of New Hampshire and NASA’s Goddard Space Flight Center have published their results online in the Journal of Geophysical Research (JGR): Planets. Lead author of the paper is research scientist Andrew Jordan of the University of New Hampshire’s Institute for the Study of Earth, Oceans, and Space (EOS).Discovering molecular hydrogen on the moon was a surprise result from NASA’s Lunar Crater Observation Sensing Satellite (LCROSS) mission, which crash-landed the LCROSS satellite’s spent Centaur rocket at 5,600 miles per hour into the Cabeus crater in the permanently shadowed region of the moon. These regions have never been exposed to sunlight and have remained at temperatures near absolute zero for billions of years, thus preserving the pristine nature of the lunar soil, or regolith.Instruments on board LCROSS trained on the resulting immense debris plume detected water vapor and water ice, the mission’s hoped-for quarry, while LRO, already in orbit around the moon, saw molecular hydrogen — a surprise.”LRO’s Lyman Alpha Mapping Project, or LAMP, detected the signature of molecular hydrogen, which was unexpected and unexplained,” says Jordan.Jordan’s JGR paper, “The formation of molecular hydrogen from water ice in the lunar regolith by energetic charged particles,” quantifies an explanation of how molecular hydrogen, which is composed of two hydrogen atoms and denoted chemically as H2, may be created below the moon’s surface.”After the finding, there were a couple of ideas for how molecular hydrogen could be formed but none of them seemed to work for the conditions in the crater or with the rocket impact.” Jordan says. “Our analysis shows that the galactic cosmic rays, which are charged particles energetic enough to penetrate below the lunar surface, can dissociate the water, H2O, into H2 through various potential pathways.”That analysis was based on data gathered by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument aboard the LRO spacecraft. Jordan is a member of the CRaTER scientific team, which is headed up by principal investigator Nathan Schwadron of EOS. Schwadron, a co-author on the JGR paper, was the first to suggest energetic particles as the possible mechanism for creating molecular hydrogen.CRaTER characterizes the global lunar radiation environment by measuring radiation dose rates from galactic cosmic rays and solar energetic particles. Says Jordan, “We used the CRaTER measurements to get a handle on how much molecular hydrogen has been formed from the water ice via charged particles.” Jordan’s computer model incorporated the CRaTER data and showed that these energetic particles can form between 10 and 100 percent of the H2 measured by LAMP.The study notes that narrowing down that percent range requires particle accelerator experiments on water ice to more accurately gauge the number of chemical reactions that result per unit of energy deposited by cosmic rays and solar energetic particles.

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Caffeine linked to low birth weight babies

Feb. 19, 2013 — Maternal nutrition is important to a developing embryo and to the health of the child later in life. Supplementing the diet with specific vitamins is known to increase health of the fetus for example folic acid (vitamin B9) reduces the risk of spina bifida. However not everything an adult might consume is beneficial to a developing baby. New research published in BioMed Central’s open access journal BMC Medicine shows that caffeine is linked to low birth weight babies and that caffeine from coffee in linked to increasing length of pregnancy.

Along with nutrients and oxygen, caffeine freely passes the placental barrier, but the developing embryo does not express the enzymes required to inactivate it efficiently. The WHO currently suggests a limit of 300mg per day during pregnancy but some countries recommend a limit of 200mg, which can be less than a single cup of coffee from some high street cafes.

To investigate the impact of maternal caffeine during pregnancy on babies, a research team from the Norwegian Institute for Public Health used information about mother’s diet and birth details collected over ten years. After excluding women with medical and pregnancy-related conditions almost 60,000 pregnancies were included in the study. All sources of caffeine were monitored in the study: coffee, tea, fizzy drinks, as well as food including cocoa-containing cakes and deserts and chocolate.

Explaining their results, Dr Verena Sengpiel, from Sahlgrenska University Hospital, Sweden, who led the project said, “Although caffeine consumption is strongly correlated with smoking which is known to increase the risk for both preterm delivery and the baby being small for gestational age at birth (SGA). In this study we found no association between either total caffeine or coffee caffeine and preterm delivery but we did find an association between caffeine and SGA. This association remained even when we looked only at non-smoking mothers which implies that the caffeine itself is also having an effect on birth weight.”

In fact they found that caffeine from all sources reduced birth weight. For a child of expected average weight (3.6kg) this equates to 21-28g lost per 100mg caffeine per day. But it was not just caffeine, but the source of caffeine, which affected pregnancy outcomes. Caffeine from all sources increased the length of the pregnancy by 5hr per 100mg caffeine per day, but caffeine intake from coffee was associated with an even longer gestational length — 8hr extra for every 100mg caffeine per day.

This association means that it is not just the caffeine in coffee which increases gestational length but either there must be a substance in coffee which is responsible for the extra time or there is a behaviour associated with coffee drinking not present in women who drink only tea (for example). SGA babies are at higher risk of both short term and lifelong health problems and it seems from these results that since even 200-300mg caffeine per day can increase the risk of SGA by almost a third these recommendations need to be re-evaluated.

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