Climate change and air pollution will combine to curb food supplies

Many studies have shown the potential for global climate change to cut food supplies. But these studies have, for the most part, ignored the interactions between increasing temperature and air pollution — specifically ozone pollution, which is known to damage crops.A new study involving researchers at MIT shows that these interactions can be quite significant, suggesting that policymakers need to take both warming and air pollution into account in addressing food security.The study looked in detail at global production of four leading food crops — rice, wheat, corn, and soy — that account for more than half the calories humans consume worldwide. It predicts that effects will vary considerably from region to region, and that some of the crops are much more strongly affected by one or the other of the factors: For example, wheat is very sensitive to ozone exposure, while corn is much more adversely affected by heat.The research was carried out by Colette Heald, an associate professor of civil and environmental engineering (CEE) at MIT, former CEE postdoc Amos Tai, and Maria van Martin at Colorado State University. Their work is described this week in the journal Nature Climate Change.Heald explains that while it’s known that both higher temperatures and ozone pollution can damage plants and reduce crop yields, “nobody has looked at these together.” And while rising temperatures are widely discussed, the impact of air quality on crops is less recognized.The effects are likely to vary widely by region, the study predicts. In the United States, tougher air-quality regulations are expected to lead to a sharp decline in ozone pollution, mitigating its impact on crops. But in other regions, the outcome “will depend on domestic air-pollution policies,” Heald says. “An air-quality cleanup would improve crop yields.”Overall, with all other factors being equal, warming may reduce crop yields globally by about 10 percent by 2050, the study found. But the effects of ozone pollution are more complex — some crops are more strongly affected by it than others — which suggests that pollution-control measures could play a major role in determining outcomes.Ozone pollution can also be tricky to identify, Heald says, because its damage can resemble other plant illnesses, producing flecks on leaves and discoloration.Potential reductions in crop yields are worrisome: The world is expected to need about 50 percent more food by 2050, the authors say, due to population growth and changing dietary trends in the developing world. So any yield reductions come against a backdrop of an overall need to increase production significantly through improved crop selections and farming methods, as well as expansion of farmland.While heat and ozone can each damage plants independently, the factors also interact. For example, warmer temperatures significantly increase production of ozone from the reactions, in sunlight, of volatile organic compounds and nitrogen oxides. …

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Worthington & Caron Proud to Again Sponsor the 4th Annual International Symposium on Lung-Sparing Therapies for Malignant Pleural Mesothelioma

On June 7 some of the leading physicians involved in the diagnosis and treatment of pleural mesothelioma will meet at the Sheraton Delfina in Santa Monica, California for the4th Annual International Symposium on Lung-Sparing Therapies for Malignant Pleural Mesothelioma. The symposium will be an all-day affair and begin at 8 am.Worthington & Caron is proud to sponsor this symposium for the fourth consecutive year.Once again, Dr. Robert B. Cameron will lead the symposium. In addition to being the Director of the UCLA Mesothelioma Comprehensive Research Program, Dr. Cameron also is the Chief of Thoracic Surgery at the West Los Angeles VA Medical Center and Scientific Advisor at the Pacific Meso Center.Although the seminar is geared toward physicians, it also offers continuing medical education …

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Primary texting bans associated with lower traffic fatalities, study finds

Researchers at the University of Alabama at Birmingham School of Public Health examined the impact texting-while-driving laws have had on roadway crash-related fatalities, and the findings are published in the August issue of the American Journal of Public Health.Of drivers in the United States ages 18-64 years, 31 percent reported they had read or sent text or email messages while driving at least once in the 30 days prior, according to 2011 data from the Centers for Disease Control and Prevention. That same year, 3,331 people were killed in crashes involving a distracted driver, and an additional 387,000 people were injured.While completing her doctoral work in the Department of Health Care Organization and Policy, Alva O. Ferdinand, Dr.P.H., J.D., conducted a longitudinal panel study to examine within-state changes in roadway fatalities after the enactment of state texting-while-driving bans using roadway fatality data captured in the Fatality Analysis Reporting System between 2000 and 2010.”Very little is known about whether laws banning texting while driving have actually improved roadway safety,” Ferdinand said. “Further, given the considerable variation in the types of laws that states have passed and whom they ban from what, it was necessary to determine which types of laws are most beneficial in improving roadway safety.”Some states have banned all drivers from texting while driving, while others have banned only young drivers from this activity, Ferdinand says. Additionally, some states’ texting bans entail secondary enforcement, meaning an officer must have another reason to stop a vehicle, like speeding or running a red light, before citing a driver for texting while driving. Other states’ texting bans entail primary enforcement, meaning an officer does not have to have another reason for stopping a vehicle.”Our results indicated that primary texting bans were significantly associated with a 3 percent reduction in traffic fatalities among all age groups, which equates to an average of 19 deaths prevented per year in states with such bans,” Ferdinand said. “Primarily enforced texting laws that banned only young drivers from texting were the most effective at reducing deaths among the 15- to 21-year-old cohort, with an associated 11 percent reduction in traffic fatalities among this age group in states with such bans.”States with secondarily enforced restrictions did not see any significant reductions in traffic fatalities.”We were a little surprised to see that primarily enforced texting bans were not associated with significant reductions in fatalities among those ages 21 to 64, who are not considered to be young drivers,” Ferdinand said. “However, states with bans prohibiting the use of cellphones without hands-free technology altogether on all drivers saw significant reductions in fatalities among this particular age group. Thus, although texting-while-driving bans were most effective for reducing traffic-related fatalities among young individuals, handheld bans appear to be most effective for adults.”Ferdinand says these results could aid policymakers interested in improving roadway safety in that they indicate the types of laws that are most effective in reducing deaths among various age groups, as well as those in states with secondarily enforced texting bans advocating for stricter, primarily enforced texting bans.Ferdinand’s mentor, Nir Menachemi, Ph.D., professor in the Department of Health Care Organization and Policy, says it is a key responsibility of health policy researchers to generate high-quality evidence on the health impact of societal policies and laws.”Clearly, distracted driving is a growing problem affecting everyone on the roadways,” Menachemi said. “It is my hope that policymakers act upon our findings so that motor-vehicle deaths can be prevented.”Story Source:The above story is based on materials provided by University of Alabama at Birmingham. …

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Increasing diversity of marketable raspberries

Raspberries are the third most popular berry in the United States. Their popularity is growing as a specialty crop for the wholesale industry and in smaller, local markets, and U-pick operations. As consumer interest in the health benefits of colorful foods increases, small growers are capitalizing on novelty fruit and vegetable crops such as different-colored raspberries. Authors of a newly published study say that increasing the diversity of raspberry colors in the market will benefit both consumers and producers. “Producers will need to know how fruit of the other color groups compare with red raspberries with regard to the many postharvest qualities,” noted the University of Maryland’s Julia Harshman, corresponding author of the study published in HortScience (March 2014).Raspberries have an extremely short shelf life, which can be worsened by postharvest decay. Postharvest susceptibility to gray mold (Botrytis cinerea) drastically reduces the shelf life of this delicate fruit. “The main goal of our research was to compare the postharvest quality of different-colored raspberries that were harvested from floricanes under direct-market conditions with minimal pesticide inputs,” Harshman said. The researchers said that, although there is abundant information in the literature regarding red raspberry production in regard to gray mold, very little research has been conducted on postharvest physiology of black, yellow, or purple raspberries.The researchers analyzed 17 varieties of raspberries at the USDA’s Agricultural Research Center in Beltsville, Maryland, examining each cultivar for characteristics such as anthocyanins, soluble solids, titratable acids, pH, color, firmness, decay and juice leakage rates, ethylene evolution, and respiration.”In comparing the four commonly grown colors of raspberry, we drew several important conclusions,” they said. “The mechanisms controlling decay and juice leakage are distinct and mediated by both biotic and abiotic factors. The colors that performed well for one area are opposite the ones that did well in the other.” For example, firmness was expected to track closely with either leakage or decay resistance; however, the analyses did not indicate this.Red raspberries, in comparison with the other three colors analyzed during the study, had the highest titratable acids (TA) and the lowest ratio of soluble solids to TA, which, the authors say, accounts for the tart raspberry flavor consumers expect.Yellow raspberries had the lowest levels of anthocyanins and phenolics. …

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Scientists create circuit board modeled on the human brain

Stanford scientists have developed faster, more energy-efficient microchips based on the human brain — 9,000 times faster and using significantly less power than a typical PC. This offers greater possibilities for advances in robotics and a new way of understanding the brain. For instance, a chip as fast and efficient as the human brain could drive prosthetic limbs with the speed and complexity of our own actions.Stanford scientists have developed a new circuit board modeled on the human brain, possibly opening up new frontiers in robotics and computing.For all their sophistication, computers pale in comparison to the brain. The modest cortex of the mouse, for instance, operates 9,000 times faster than a personal computer simulation of its functions.Not only is the PC slower, it takes 40,000 times more power to run, writes Kwabena Boahen, associate professor of bioengineering at Stanford, in an article for the Proceedings of the IEEE.”From a pure energy perspective, the brain is hard to match,” says Boahen, whose article surveys how “neuromorphic” researchers in the United States and Europe are using silicon and software to build electronic systems that mimic neurons and synapses.Boahen and his team have developed Neurogrid, a circuit board consisting of 16 custom-designed “Neurocore” chips. Together these 16 chips can simulate 1 million neurons and billions of synaptic connections. The team designed these chips with power efficiency in mind. Their strategy was to enable certain synapses to share hardware circuits. The result was Neurogrid — a device about the size of an iPad that can simulate orders of magnitude more neurons and synapses than other brain mimics on the power it takes to run a tablet computer.The National Institutes of Health funded development of this million-neuron prototype with a five-year Pioneer Award. Now Boahen stands ready for the next steps — lowering costs and creating compiler software that would enable engineers and computer scientists with no knowledge of neuroscience to solve problems — such as controlling a humanoid robot — using Neurogrid.Its speed and low power characteristics make Neurogrid ideal for more than just modeling the human brain. Boahen is working with other Stanford scientists to develop prosthetic limbs for paralyzed people that would be controlled by a Neurocore-like chip.”Right now, you have to know how the brain works to program one of these,” said Boahen, gesturing at the $40,000 prototype board on the desk of his Stanford office. …

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Sugar-sweetened beverages contribute to U.S. obesity epidemic, particularly among children

In response to the ongoing policy discussions on the role of sugar-sweetened beverages (SSBs) on weight and health, The Obesity Society (TOS) concludes that SSBs contribute to the United States’ obesity epidemic, particularly among children. Based on an in-depth analysis of the current research, TOS’s position statement unveiled today provides several recommendations for improving health, including that children minimize their consumption of SSBs.”There’s no arguing with the fact that the high rates of obesity in the U.S. are troubling for our nation’s health, specifically the recently reported rise in severe obesity among children in JAMA Pediatrics,” said TOS spokesperson Diana Thomas, PhD, Professor at Montclair State University and Director of the Center for Quantitative Obesity Research. “Following a thorough review and analysis of the existing research, TOS concludes that, by adding more non-nutritious calories to the American diet, SSBs have contributed to the U.S. obesity epidemic. Further, we recommend that to maintain and improve health children minimize drinking SSBs and adults reduce or avoid SSB consumption as part of an overall strategy to reduce calories.”According to the position statement posted online, TOS defines SSBs as sodas, sports drinks and other types of beverages that are primarily made up of water and added sugar. Consumption of these drinks in the U.S. remains high — Americans report that SSBs comprise 6-7% of overall calorie intake.”Despite the challenges researchers have faced with isolating the impact of specific foods or beverages on body weight, the studies conducted on SSBs thus far have generated important and meaningful data leading to our conclusion,” said Dr. Thomas. “The evidence shows that individuals with a higher BMI consume more SSBs than their leaner counterparts, and that decreasing SSB consumption may reduce overall calorie intake and help individuals with obesity or overweight reach healthy weight goals.”Weight gain occurs when total energy intake exceeds energy expenditure for extended periods of time. …

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First peanut genome sequenced

The International Peanut Genome Initiative — a group of multinational crop geneticists who have been working in tandem for the last several years — has successfully sequenced the peanut’s genome.Scott Jackson, director of the University of Georgia Center for Applied Genetic Technologies in the College of Agricultural and Environmental Sciences, serves as chair of the International Peanut Genome Initiative, or IPGI.The new peanut genome sequence will be available to researchers and plant breeders across the globe to aid in the breeding of more productive and more resilient peanut varieties.Peanut, known scientifically as Arachis hypogaea and also called groundnut, is important both commercially and nutritionally. While the oil- and protein-rich legume is seen as a cash crop in the developed world, it remains a valuable sustenance crop in developing nations.”The peanut crop is important in the United States, but it’s very important for developing nations as well,” Jackson said. “In many areas, it is a primary calorie source for families and a cash crop for farmers.”Globally, farmers tend about 24 million hectares of peanuts each year and produce about 40 million metric tons.”Improving peanut varieties to be more drought-, insect- and disease-resistant can help farmers in developed nations produce more peanuts with fewer pesticides and other chemicals and help farmers in developing nations feed their families and build more secure livelihoods,” said plant geneticist Rajeev Varshney of the International Crops Research Institute for Semi-Arid Tropics in India, who serves on the IPGI.The effort to sequence the peanut genome has been underway for several years. While peanuts were successfully bred for intensive cultivation for thousands of years, relatively little was known about the legume’s genetic structure because of its complexity, according to Peggy Ozias-Akins, a plant geneticist on the UGA Tifton campus who also works with the IPGI and is director of the UGA Institute of Plant Breeding, Genetics and Genomics.”Until now, we’ve bred peanuts relatively blindly, as compared to other crops,” said IPGI plant geneticist David Bertioli of the Universidade de Braslia. “We’ve had less information to work with than we do with many crops, which have been more thoroughly researched and understood.”The peanut in fields today is the result of a natural cross between two wild species, Arachis duranensis and Arachis ipaensis, which occurred in north Argentina between 4,000 and 6,000 years ago. Because its ancestors were two different species, today’s peanut is a polyploid, meaning the species can carry two separate genomes, designated A and B subgenomes.To map the peanut’s structure, researchers sequenced the genomes of the two ancestral parents because together they represent the cultivated peanut. The sequences provide researchers access to 96 percent of all peanut genes in their genomic context, providing the molecular map needed to more quickly breed drought- and disease-resistant, lower-input and higher-yielding varieties of peanuts.The two ancestor wild species had been collected in nature, conserved in germplasm banks and then used by the IPGI to better understand the peanut genome. The genomes of the two ancestor species provide excellent models for the genome of the cultivated peanut. A. duranenis serves as a model for the A subgenome of the cultivated peanut while A. …

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Amazon Studied to Predict Impact of Climate Change

Three extreme weather events in the Amazon Basin in the last decade are giving scientists an opportunity to make observations that will allow them to predict the impacts of climate change and deforestation on some of the most important ecological processes and ecosystem services of the Amazon River wetlands.Scientists from Virginia Tech, the Woods Hole Research Center, and the University of California, Santa Barbara, funded by NASA, are collaborating with Brazilian scientists to explore the ecosystem consequences of the extreme droughts of 2005 and 2010 and the extreme flood of 2009.”The research fills an important gap in our understanding of the vulnerability of tropical river-forest systems to changes in climate and land cover,” said the project’s leader, Leandro Castello, assistant professor of fish and wildlife conservation in Virginia Tech’s College of Natural Resources and Environment.The huge study area encompasses 1.7 million square miles, the equivalent of half of the continental United States.In addition to historical records and ground observations, the researchers will use newly available Earth System Data Records from NASA — satellite images of the Amazon and its tributaries over the complete high- and low-water cycles.NASA is funding the study with a $1.53 million grant shared among the three institutions.”Amazon floodplains and river channels — maintained by seasonal floods — promote nutrient cycling and high biological production, and support diverse biological communities as well as human populations with one of the highest per capita rates of fish consumption,” said Castello.The researchers will look at how the natural seasonality of river levels influences aquatic and terrestrial grasses, fisheries, and forest productivity in the floodplains, and how extreme events such as floods and droughts may disturb this cycle.”We are confident that deforestation and climate change will, in the future, lead to more frequent and severe floods and droughts,” said Michael Coe, a senior scientist at the Woods Hole Research Center. “It is important that we understand how the Amazon River and ecosystem services such as fisheries are affected so that we can devise mitigation strategies.”Amazonian grasses, sometimes called macrophytes, convert atmospheric carbon to plant biomass, which is then processed by aquatic microorganisms upon decomposition.”Terrestrial grasses grow during the short window when water levels are low, sequestering some carbon, and then die when the floods arrive, releasing the carbon into the aquatic system,” said Thiago Silva, an assistant professor of geography at So Paulo State University in Rio Claro, Brazil. “They are followed by aquatic grasses that need to grow extremely fast to surpass the rising floods and then die off during the receding-water period.””Although most of the macrophyte carbon is released back to the atmosphere in the same form that it is assimilated, carbon dioxide, some of it is actually exported to the ocean as dissolved carbon or released to the atmosphere as methane, a gas that has a warming potential 20 times larger than carbon dioxide,” said John Melack, a professor at the University of California, Santa Barbara.Researchers will measure plant growth and gas exchange, and use photographs from the field and satellites.Two other Amazon resources — fisheries and forests — are important to the livelihood of the people of the region.”We will combine water level, fishing effort, and fish life-history traits to understand the impact of droughts and floods on fishery yields,” said Castello, whose specialty is Amazon fisheries. “Floods in the Amazon are almost a blessing because in some years they can almost double the amount of fish in the river that is available for fishermen and society.”The fishery data include approximately 90,000 annual interview records of fisheries activities on the number of fishers, time spent fishing, characteristics of fishing boats and gear used, and weight of the catch for 40 species. The hydrological data include daily water level measurements recorded in the Madeira, Purus, and Amazonas-Solimes rivers.The researchers will examine the potential impact of future climate scenarios on the extent and productivity of floodplain forests — those enriched by rising waters, called whitewater river forests, and nutrient-poor blackwater river forests.For example, extreme droughts may reduce productivity due to water stress and increases in the frequency and severity of forest fires. Prolonged periods of inundation, on the other hand, may decrease productivity or increase mortality due to water-logging stress.”We will evaluate these responses for the first time at a regional scale using remotely sensed indicators of vegetation condition and fire-induced tree mortality to measure the response of floodplain forests to inter-annual flood variability and extreme climate events,” said Marcia Macedo, a research associate at the Woods Hole Research Center.Researchers will measure tree litter dry weight, depth of flooding, tree height and diameter, and stand density. They will also use photographs and satellite images.Previous research has focused on Amazon upland forests and the potential impacts of deforestation, fire, and drought. The research team will compare new greenhouse gas simulations to previous simulations.”Our research informs large river ecology globally because natural flowing rivers like the Amazon are rare these days, and most research to date, being done in North America and Europe, has focused on degraded systems,” Castello said.

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Warming climate may spread drying to a third of earth: Heat, not just rainfall, plays into new projections

Increasing heat is expected to extend dry conditions to far more farmland and cities by the end of the century than changes in rainfall alone, says a new study. Much of the concern about future drought under global warming has focused on rainfall projections, but higher evaporation rates may also play an important role as warmer temperatures wring more moisture from the soil, even in some places where rainfall is forecasted to increase, say the researchers.The study is one of the first to use the latest climate simulations to model the effects of both changing rainfall and evaporation rates on future drought. Published this month in the journal Climate Dynamics, the study estimates that 12 percent of land will be subject to drought by 2100 through rainfall changes alone; but the drying will spread to 30 percent of land if higher evaporation rates from the added energy and humidity in the atmosphere is considered. An increase in evaporative drying means that even regions expected to get more rain, including important wheat, corn and rice belts in the western United States and southeastern China, will be at risk of drought. The study excludes Antarctica.”We know from basic physics that warmer temperatures will help to dry things out,” said the study’s lead author, Benjamin Cook, a climate scientist with joint appointments at Columbia University’s Lamont-Doherty Earth Observatory and the NASA Goddard Institute for Space Studies. “Even if precipitation changes in the future are uncertain, there are good reasons to be concerned about water resources.”In its latest climate report, the International Panel on Climate Change (IPCC) warns that soil moisture is expected to decline globally and that already dry regions will be at greater risk of agricultural drought. The IPCC also predicts a strong chance of soil moisture drying in the Mediterranean, southwestern United States and southern African regions, consistent with the Climate Dynamics study.Using two drought metric formulations, the study authors analyze projections of both rainfall and evaporative demand from the collection of climate model simulations completed for the IPCC’s 2013 climate report. Both metrics agree that increased evaporative drying will probably tip marginally wet regions at mid-latitudes like the U.S. Great Plains and a swath of southeastern China into aridity. If precipitation were the only consideration, these great agricultural centers would not be considered at risk of drought. …

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Million suns shed light on fossilized plant

Scientists have used one of the brightest lights in the Universe to expose the biochemical structure of a 50 million-year-old fossil plant to stunning visual effect.The team of palaeontologists, geochemists and physicists investigated the chemistry of exceptionally preserved fossil leaves from the Eocene-aged ‘Green River Formation’ of the western United States by bombarding the fossils with X-rays brighter than a million suns produced by synchrotron particle accelerators.Researchers from Britain’s University of Manchester and Diamond Light Source and the Stanford Synchrotron Radiation Lightsource in the US have published their findings, along with amazing images, in Metallomics; one of the images is featured on the cover of the latest edition of the Royal Society of Chemistry journal.Lead author Dr Nicholas Edwards, a postdoctoral researcher at The University of Manchester, said: “The synchrotron has already shown its potential in teasing new information from fossils, in particular our group’s previous work on pigmentation in fossil animals. With this study, we wanted to use the same techniques to see whether we could extract a similar level of biochemical information from a completely different part of the tree of life.”To do this we needed to test the chemistry of the fossil plants to see if the fossil material was derived directly from the living organisms or degraded and replaced by the fossilisation process.”We know that plant chemistry can be preserved over hundreds of millions of years — this preserved chemistry powers our society today in the form of fossil fuels. However, this is just the ‘combustible’ part; until now no one has completed this type of study of the other biochemical components of fossil plants, such as metals.”By combining the unique capabilities of two synchrotron facilities, the team were able to produce detailed images of where the various elements of the periodic table were located within both living and fossil leaves, as well as being able to show how these elements were combined with other elements.The work shows that the distribution of copper, zinc and nickel in the fossil leaves was almost identical to that in modern leaves. Each element was concentrated in distinct biological structures, such as the veins and the edges of the leaves, and the way these trace elements and sulphur were attached to other elements was very similar to that seen in modern leaves and plant matter in soils.Co-author Professor Roy Wogelius, from Manchester’s School of Earth, Atmospheric and Environmental Sciences, said: “This type of chemical mapping and the ability to determine the atomic arrangement of biologically important elements, such as copper and sulphur, can only be accomplished by using a synchrotron particle accelerator.”In one beautiful specimen, the leaf has been partially eaten by prehistoric caterpillars — just as modern caterpillars feed — and their feeding tubes are preserved on the leaf. The chemistry of these fossil tubes remarkably still matches that of the leaf on which the caterpillars fed.”The data from a suite of other techniques has led the team to conclude that the chemistry of the fossil leaves is not wholly sourced from the surrounding environment, as has previously been suggested, but represents that of the living leaves. Another modern-day connection suggests a way in which these specimens are so beautifully preserved over millions of years.Manchester palaeontologist and co-author Dr Phil Manning said: “We think that copper may have aided preservation by acting as a ‘natural’ biocide, slowing down the usual microbial breakdown that would destroy delicate leaf tissues. This property of copper is used today in the same wood preservatives that you paint on your garden fence before winter approaches.”Story Source:The above story is based on materials provided by Manchester University. Note: Materials may be edited for content and length.

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Strictly limiting hours surgical residents can work has not improved patient safety

Strictly limiting the number of hours surgical residents can work has not improved patient outcomes but may have increased complications for some patients and led to higher failure rates on certification exams, a research paper concludes.Traditionally, doctors in the residency phase of their training spent very long hours in a hospital — often around-the-clock — so they could see a wide variety and high volume of patients. In the last 10 years, health authorities started limiting those hours in the hopes of improving patient safety and the education and well-being of doctors.In 2003, the Accreditation Council for Graduate Medical Education in the United States limited residents’ hours to 80 per week. In 2011, the council prohibited first-year residents from working 24 shifts.In Canada, on-call shifts were limited to 16 hours in Quebec after a provincial arbitrator ruled that in 2011 that a 24-hour on-call shift posed a danger to residents’ health and violated the Charter of Rights. Last year a National Steering Committee on Resident Duty Hours said the status quo was unacceptable and that shifts of 24 hours or longer without sleep should be avoided. It urged all provinces and health care institutions to develop comprehensive strategies to minimize fatigue and fatigue-related risks during residency.Dr. Najma Ahmad, a trauma surgeon at St. Michael’s Hospital who was a member of the national group, published a paper today in the Annals of Surgery that found the too-restricted hours may work for some residents, but not for surgical residents.”A one-size fits all approach to resident duty hours may not be appropriate for all specialties,” said Dr. Ahmed, noting that the American College of Surgeons Division of education has stated that mastery in surgery requires “extensive and immersive experiences.”She said the emphasis should be on reducing the amount of non-educational work residents do and to find ways to manage fatigue such as making sure they get enough uninterrupted sleep. Dr. Ahmed, who is also director of the University of Toronto’s General Surgery Program, conducted a meta-analysis of 135 articles on the impact of resident duty hours on clinical and educational outcomes in surgery.”In surgery, recent changes in hours for residents are not consistently associated with improved resident well-being and may have negative impacts on patient outcomes and performance on certification exams,” she said.Dr. …

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Guns Loom Large in Childhood Death Statistics

You can’t go more than a couple of months without seeing another news headline about a school shooting, or a shooting incident involving a child. While these stories are shocking, school shootings account for only a small number of the gun-related injuries and fatalities that children suffer every year as a result of gunshots. In fact, most gun injuries happen in the home and at the hands of other children who had no intention of hurting anybody.Children and Gun DeathsAccording to a recent study presented to a conference of the American Academy of Pediatrics, over 500 children die every year from gunshot wounds. That number represents a 60 percent increase in a single decade. Handguns, by far, account for the most injuries and deaths. Over 80 percent of all children who are injured by firearms suffer injuries inflicted by handguns.The study looked at data compiled between 1997 and 2009. In 1997, 4,270 children under the age of 20 suffered a gunshot injury. By 2009, that number increase to 7,730, a jump of about 55 percent. Further, 317 children died of gunshot injuries in 1997, while 503 died of such injuries in 2009.Disproportionate DangerOther studies have shown that gunshots pose a disproportionately high fatality risk to children. Even though gunshot wounds account for only 1% of the total number of injuries children suffer each year, they account for 21% of deaths that result from childhood injury.When a child is shot, that child has a 32% chance of requiring major surgery. …

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New school meal standards significantly increase fruit, vegetable consumption

New federal standards launched in 2012 that require schools to offer healthier meals have led to increased fruit and vegetable consumption, according to a new study from Harvard School of Public Health (HSPH) researchers. The study, the first to examine school food consumption both before and after the standards went into effect, contradicts criticisms that the new standards have increased food waste.”There is a push from some organizations and lawmakers to weaken the new standards. We hope the findings, which show that students are consuming more fruits and vegetables, will discourage those efforts,” said lead author Juliana Cohen, research fellow in the Department of Nutrition at HSPH.Some 32 million students eat school meals every day; for many low-income students, up to half their daily energy intake is from school meals. Under the previous dietary guidelines, school breakfasts and lunches were high in sodium and saturated fats and were low in whole grains and fiber. The new standards from the United States Department of Agriculture (USDA) aimed to improve the nutritional quality of school meals by making whole grains, fruits, and vegetables more available, requiring the selection of a fruit or vegetable, increasing the portion sizes of fruits and vegetables, removing trans fats, and placing limits on total calories and sodium levels.The researchers collected plate waste data among 1,030 students in four schools in an urban, low-income school district both before (fall 2011) and after (fall 2012) the new standards went into effect. Following the implementation of the new standards, fruit selection increased by 23.0%; entre and vegetable selection remained unchanged. In addition, consumption of vegetables increased by 16.2%; fruit consumption was unchanged, but because more students selected fruit, overall, more fruit was consumed post-implementation.Importantly, the new standards did not result in increased food waste, contradicting anecdotal reports from food service directors, teachers, parents, and students that the regulations were causing an increase in waste due to both larger portion sizes and the requirement that students select a fruit or vegetable. However, high levels of fruit and vegetable waste continued to be a problem — students discarded roughly 60%-75% of vegetables and 40% of fruits on their trays. The authors say that schools must focus on improving food quality and palatability to reduce waste.”The new school meal standards are the strongest implemented by the USDA to date, and the improved dietary intakes will likely have important health implications for children,” wrote the researchers.Story Source:The above story is based on materials provided by Harvard School of Public Health. Note: Materials may be edited for content and length.

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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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Pre-term birth leads to increased risk of asthma, wheezing disorders

Researchers at Brigham and Women’s Hospital (BWH) in Boston, Massachusetts, in collaboration with investigators at the Maastricht University Medical Centre and Maastricht University School of Public Health in the Netherlands and The University of Edinburgh in the United Kingdom, have published findings strongly suggesting that preterm birth (prior to 37 weeks gestation) increases the risk of asthma and wheezing disorders during childhood and that the risk of developing these conditions increases as the degree of prematurity increases.The findings are based on a systematic review and meta-analysis of 30 studies that investigated the association between preterm birth and asthma/wheezing disorders among 1.5 million children. These studies were conducted between 1995 and the present, a time span chosen to allow for recent changes in the management of prematurity.Across the studies, 13.7 percent of preterm babies developed asthma/wheezing disorders compared with 8.3 percent of babies born at term, representing a 70 percent increased risk. Children born very early (before 32 weeks gestation) had approximately three times the risk of developing asthma/wheezing disorders compared with babies born at term.”Worldwide, more than 11 percent of babies are born preterm,” said Aziz Sheikh, MD, corresponding author and Harkness Fellow in Health Care Policy and Practice in the Division of General Internal Medicine and Primary Care at Brigham and Women’s Hospital. “As asthma is a chronic condition, our findings underscore the need to improve our understanding of the mechanisms underlying the association between preterm birth and asthma/wheezing disorders in order to develop preventive and therapeutic interventions.”Story Source:The above story is based on materials provided by Brigham and Women’s Hospital. Note: Materials may be edited for content and length.

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Hop leaves — discarded in beer brewing — have substances that could fight dental diseases

Beer drinkers know that hops are what gives the drink its bitterness and aroma. Recently, scientists reported that the part of hops that isn’t used for making beer contains healthful antioxidants and could be used to battle cavities and gum disease. In a new study in ACS’ Journal of Agricultural and Food Chemistry, they say that they’ve identified some of the substances that could be responsible for these healthful effects.Yoshihisa Tanaka and colleagues note that their earlier research found that antioxidant polyphenols, contained in the hop leaves (called bracts) could help fight cavities and gum disease. Extracts from bracts stopped the bacteria responsible for these dental conditions from being able to stick to surfaces and prevented the release of some bacterial toxins. Every year, farmers harvest about 2,300 tons of hops in the United States, but the bracts are not used for making beer and are discarded. Thus, there is potentially a large amount of bracts that could be repurposed for dental applications. But very few of the potentially hundreds of compounds in the bracts have been reported. Tanaka’s group decided to investigate what substances in these leaves might cause those healthful effects.Using a laboratory technique called chromatography, they found three new compounds, one already-known compound that was identified for the first time in plants and 20 already-known compounds that were found for the first time in hops. The bracts also contained substantial amounts of proanthocyanidins, which are healthful antioxidants.Story Source:The above story is based on materials provided by American Chemical Society. Note: Materials may be edited for content and length.

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Fat or flat: Getting galaxies into shape

Australian astronomers have discovered what makes some spiral galaxies fat and bulging while others are flat discs — and it’s all about how fast they spin.The research, led by the International Centre for Radio Astronomy Research (ICRAR) in Perth, found that fast-rotating spiral galaxies are flat and thin while equally sized galaxies that rotate slowly are fatter.The study was published today in Astrophysical Journal.ICRAR Research Associate Professor Danail Obreschkow, from The University of Western Australia, said it is a much-debated mystery why galaxies look so different to each other.”Some galaxies are very flat discs of stars and others are more bulging or even spherical,” he said.”Much of the last century of research has been dedicated to understanding this diversity of galaxies in the Universe and with this paper we’ve made a step towards understanding how this came about by showing that the rotation of spiral galaxies is a key driver for their shape.”The study looked at 16 galaxies — all between 10 million and 50 million light years from Earth — using data from a survey called THINGS.”The THINGS survey shows you the cold gas in the galaxies, not only where it is but how it moves,” Dr Obreschkow said.”That’s a crucial point if you want to measure the spin, you can’t just take a photograph, you have to take a special picture that shows you the motion.”Dr Obreschkow said the shape of a spiral galaxy is determined by both its spin and its mass and if you leave a galaxy on its own for billions of years both quantities will stay the same.He said the way galaxies are formed looks a bit similar to a carousel made of an elastic disc.”If the carousel is at rest, the elastic disc is quite small,” Dr Obreschkow said.”But when the whole thing is spinning the elastic disc becomes larger because it’s feeling the effects of centrifugal force.”Our own Milky Way is a relatively flat disc with only a small bulge, the shape of which can be seen in the night sky.”The white band of the Milky Way across the sky is a relatively thin band of constant thickness. However when you look right at the centre near the Sagittarius constellation you can actually see a thickening of the Milky Way, which is the bulge,” Dr Obreschkow said. He and co-author, Swinburne University Professor Karl Glazebrook, were able to measure the effect of spin on galaxies more than ten times better than anyone previously.The study used data collected at the Karl G. Jansky Very Large Array in the United States, one of the most famous radio telescopes in the world and a significant pathfinder for the Square Kilometre Array.Story Source:The above story is based on materials provided by International Centre for Radio Astronomy Research (ICRAR). Note: Materials may be edited for content and length.

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Brain differences linked to insomnia identified by researchers

Johns Hopkins researchers report that people with chronic insomnia show more plasticity and activity than good sleepers in the part of the brain that controls movement.”Insomnia is not a nighttime disorder,” says study leader Rachel E. Salas, M.D., an assistant professor of neurology at the Johns Hopkins University School of Medicine. “It’s a 24-hour brain condition, like a light switch that is always on. Our research adds information about differences in the brain associated with it.”Salas and her team, reporting in the March issue of the journal Sleep, found that the motor cortex in those with chronic insomnia was more adaptable to change — more plastic — than in a group of good sleepers. They also found more “excitability” among neurons in the same region of the brain among those with chronic insomnia, adding evidence to the notion that insomniacs are in a constant state of heightened information processing that may interfere with sleep.Researchers say they hope their study opens the door to better diagnosis and treatment of the most common and often intractable sleep disorder that affects an estimated 15 percent of the United States population.To conduct the study, Salas and her colleagues from the Department of Psychiatry and Behavioral Sciences and the Department of Physical Medicine and Rehabilitation used transcranial magnetic stimulation (TMS), which painlessly and noninvasively delivers electromagnetic currents to precise locations in the brain and can temporarily and safely disrupt the function of the targeted area. TMS is approved by the U.S. Food and Drug Administration to treat some patients with depression by stimulating nerve cells in the region of the brain involved in mood control.The study included 28 adult participants — 18 who suffered from insomnia for a year or more and 10 considered good sleepers with no reports of trouble sleeping. Each participant was outfitted with electrodes on their dominant thumb as well as an accelerometer to measure the speed and direction of the thumb.The researchers then gave each subject 65 electrical pulses using TMS, stimulating areas of the motor cortex and watching for involuntary thumb movements linked to the stimulation. Subsequently, the researchers trained each participant for 30 minutes, teaching them to move their thumb in the opposite direction of the original involuntary movement. They then introduced the electrical pulses once again.The idea was to measure the extent to which participants’ brains could learn to move their thumbs involuntarily in the newly trained direction. …

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DNA test better than standard screens in identifying fetal chromosome abnormalities

A study in this week’s New England Journal of Medicine potentially has significant implications for prenatal testing for major fetal chromosome abnormalities. The study found that in a head-to-head comparison of noninvasive prenatal testing using cell free DNA (cfDNA) to standard screening methods, cfDNA testing (verifi prenatal test, Illumina, Inc.) significantly reduced the rate of false positive results and had significantly higher positive predictive values for the detection of fetal trisomies 21 and 18.A team of scientists, led by Diana W. Bianchi, MD, Executive Director of the Mother Infant Research Institute at Floating Hospital for Children at Tufts Medical Center, reports the results of their clinical trial using non-invasive cell-free DNA prenatal testing in a general obstetrical population of pregnant women, in an article entitled “DNA sequencing versus standard prenatal aneuploidy screening.”The multi-center, blinded study analyzed samples from 1,914 pregnant women, and found that noninvasive cfDNA testing had a ten-fold improvement in the positive predictive value for trisomy 21, commonly known as Down syndrome, compared to standard prenatal aneuploidy screening methods (aneuploidy is a term for one or more extra or missing chromosomes). Importantly, the cfDNA test performed consistently well in a general population of pregnant women, regardless of their risk for fetal chromosomal abnormalities. Previous studies have shown that the tests were more accurate for women who had higher risks for fetal chromosomal abnormalities, but this was the first time that the cfDNA tests were compared in a general obstetrical population to the variety of blood and ultrasound tests that comprise the current standard of care in the United States.”We found that the major advantage of noninvasive prenatal DNA testing was the significant reduction of the false positive rate,” said Bianchi. “Prenatal testing using cell-free DNA as a primary screen could eliminate the need for many of the invasive diagnostic procedures (such as amniocentesis) that are performed to confirm a positive screen.”Prenatal screening for fetal aneuploidy is recommended by the American College of Obstetricians and Gynecologists as part of routine prenatal care. Researchers compared current standard noninvasive aneuploidy testing techniques — serum biochemical assays and nuchal translucency measurements using ultrasound — with a noninvasive, cell-free DNA test. Serum biochemical assays identify biomarkers for chromosomal abnormalities while nuchal translucency measurements use ultrasound examinations to measure the thickness of a space at the back of the baby’s neck. With Down syndrome, more fluid is present, making the space appear thicker. Cell-free DNA testing works by mapping and counting DNA fragments in a mother’s blood sample and comparing the measurements to normal reference samples. …

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Scientists complete the top quark puzzle

Scientists on the CDF and DZero experiments at the U.S. Department of Energy’s Fermi National Accelerator Laboratory have announced that they have found the final predicted way of creating a top quark, completing a picture of this particle nearly 20 years in the making.The two collaborations jointly announced on Friday, Feb. 21, that they had observed one of the rarest methods of producing the elementary particle — creating a single top quark through the weak nuclear force, in what is called the “s-channel.” For this analysis, scientists from the CDF and DZero collaborations sifted through data from more than 500 trillion proton-antiproton collisions produced by the Tevatron from 2001 to 2011. They identified about 40 particle collisions in which the weak nuclear force produced single top quarks in conjunction with single bottom quarks.Top quarks are the heaviest and among the most puzzling elementary particles. They weigh even more than the Higgs boson — as much as an atom of gold — and only two machines have ever produced them: Fermilab’s Tevatron and the Large Hadron Collider at CERN. There are several ways to produce them, as predicted by the theoretical framework known as the Standard Model, and the most common one was the first one discovered: a collision in which the strong nuclear force creates a pair consisting of a top quark and its antimatter cousin, the anti-top quark.Collisions that produce a single top quark through the weak nuclear force are rarer, and the process scientists on the Tevatron experiments have just announced is the most challenging of these to detect. This method of producing single top quarks is among the rarest interactions allowed by the laws of physics. The detection of this process was one of the ultimate goals of the Tevatron, which for 25 years was the most powerful particle collider in the world.”This is an important discovery that provides a valuable addition to the picture of the Standard Model universe,” said James Siegrist, DOE associate director of science for high energy physics. “It completes a portrait of one of the fundamental particles of our universe by showing us one of the rarest ways to create them.”Searching for single top quarks is like looking for a needle in billions of haystacks. Only one in every 50 billion Tevatron collisions produced a single s-channel top quark, and the CDF and DZero collaborations only selected a small fraction of those to separate them from background, which is why the number of observed occurrences of this particular channel is so small. …

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