Leaf-mining insects destroyed with the dinosaurs, others quickly appeared

After the asteroid impact at the end of the Cretaceous period that triggered the dinosaurs’ extinction and ushered in the Paleocene, leaf-mining insects in the western United States completely disappeared. Only a million years later, at Mexican Hat, in southeastern Montana, fossil leaves show diverse leaf-mining traces from new insects that were not present during the Cretaceous, according to paleontologists.”Our results indicate both that leaf-mining diversity at Mexican Hat is even higher than previously recognized, and equally importantly, that none of the Mexican Hat mines can be linked back to the local Cretaceous mining fauna,” said Michael Donovan, graduate student in geosciences, Penn State.Insects that eat leaves produce very specific types of damage. One type is from leaf miners — insect larvae that live in the leaves and tunnel for food, leaving distinctive feeding paths and patterns of droppings.Donovan, Peter Wilf, professor of geosciences, Penn State, and colleagues looked at 1,073 leaf fossils from Mexican Hat for mines. They compared these with more than 9,000 leaves from the end of the Cretaceous, 65 million years ago, from the Hell Creek Formation in southwestern North Dakota, and with more than 9,000 Paleocene leaves from the Fort Union Formation in North Dakota, Montana and Wyoming. The researchers present their results in today’s (July 24) issue of PLOS ONE.”We decided to focus on leaf miners because they are typically host specific, feeding on only a few plant species each,” said Donovan. “Each miner also leaves an identifiable mining pattern.”The researchers found nine different mine-damage types at Mexican Hat attributable to the larvae of moths, wasps and flies, and six of these damage types were unique to the site.The researchers were unsure whether the high diversity of leaf miners at Mexican Hat compared to other early Paleocene sites, where there is little or no leaf mining, was caused by insects that survived the extinction event in refugia — areas where organisms persist during adverse conditions — or were due to range expansions of insects from somewhere else during the early Paleocene.However, with further study, the researchers found no evidence of the survival of any leaf miners over the Cretaceous-Paleocene boundary, suggesting an even more total collapse of terrestrial food webs than has been recognized previously.”These results show that the high insect damage diversity at Mexican Hat represents an influx of novel insect herbivores during the early Paleocene and not a refugium for Cretaceous leaf miners,” said Wilf. “The new herbivores included a startling diversity for any time period, and especially for the classic post-extinction disaster interval.”Insect extinction across the Cretaceous-Paleocene boundary may have been directly caused by catastrophic conditions after the asteroid impact and by the disappearance of host plant species. While insect herbivores constantly need leaves to survive, plants can remain dormant as seeds in the ground until more auspicious circumstances occur.The low-diversity flora at Mexican Hat is typical for the area in the early Paleocene, so what caused the high insect damage diversity?Insect outbreaks are associated with a rapid population increase of a single insect species, so the high diversity of mining damage seen in the Mexican Hat fossils makes the possibility of an outbreak improbable.The researchers hypothesized that the leaf miners that are seen in the Mexican Hat fossils appeared in that area because of a transient warming event, a number of which occurred during the early Paleocene.”Previous studies have shown a correlation between temperature and insect damage diversity in the fossil record, possibly caused by evolutionary radiations or range shifts in response to a warmer climate,” said Donovan. “Current evidence suggests that insect herbivore extinction decreased with increasing distance from the asteroid impact site in Mexico, so pools of surviving insects would have existed elsewhere that could have provided a source for the insect influx that we observed at Mexican Hat.”Story Source:The above story is based on materials provided by Penn State. The original article was written by A’ndrea Eluse Messer. …

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Radiation damage at the root of Chernobyl’s ecosystems

Radiological damage to microbes near the site of the Chernobyl disaster has slowed the decomposition of fallen leaves and other plant matter in the area, according to a study just published in the journal Oecologia. The resulting buildup of dry, loose detritus is a wildfire hazard that poses the threat of spreading radioactivity from the Chernobyl area.Tim Mousseau, a professor of biology and co-director of the Chernobyl and Fukushima Research Initiatives at the University of South Carolina, has done extensive research in the contaminated area surrounding the Chernobyl nuclear facility, which exploded and released large quantities of radioactive compounds in the Ukraine region of the Soviet Union in 1986. He and frequent collaborator Anders Mller of Universit Paris-Sud noticed something unusual in the course of their work in the Red Forest, the most contaminated part of the Chernobyl Exclusion Zone.”We were stepping over all these dead trees on the ground that had been killed by the initial blast,” Mousseau said. “Some 15 or 20 years later, these tree trunks were in pretty good shape. If a tree had fallen in my backyard, it would be sawdust in 10 years or so.”They set out to assess the rate at which plant material decomposed as a function of background radiation, placing hundreds of samples of uncontaminated leaf litter (pine needles and oak, maple and birch leaves) in mesh bags throughout the area. The locations were chosen to cover a range of radiation doses, and the samples were retrieved after nine months outdoors.A statistical analysis of the weight loss of each leaf litter sample after those nine months showed that higher background radiation was associated with less weight loss. The response was proportional to radiation dose, and in the most contaminated regions, the leaf loss was 40 percent less than in control regions in Ukraine with normal background radiation levels.They also measured the thickness of the forest floor in the same areas where samples were placed. They found that it was thicker in places with higher background radiation.The team concluded that the bacteria and fungi that decompose plant matter in healthy ecosystems are hindered by radioactive contamination. They showed a smaller effect for small invertebrates, such as termites, that also contribute to decomposition of plant biomass.According to Mousseau, slower decomposition is likely to indirectly slow plant growth, too, given that the products of decomposition are nutrients for new plants. The team recently reported diminished tree growth near Chernobyl, which he says likely results both from direct radiation effects and indirect effects such as reduced nutrient supply.”It’s another facet of the impacts of low-dose-rate radioactive contaminants on the broader ecosystem,” Mousseau says. …

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Superbright, fast X-rays image single layer of proteins

In biology, a protein’s shape is key to understanding how it causes disease or toxicity. Researchers who use X-rays to take snapshots of proteins need a billion copies of the same protein stacked and packed into a neat crystal. Now, scientists using exceptionally bright and fast X-rays can take a picture that rivals conventional methods with a sheet of proteins just one protein molecule thick.Using a type of laser known as XFEL, the technique opens the door to learning the structural details of almost 25 percent of known proteins, many of which have been overlooked due to their inability to stack properly. The team of researchers led by the Department of Energy’s Pacific Northwest and Lawrence Livermore National Laboratories report their results with this unique form of X-ray diffraction in the March issue of the International Union of Crystallography Journal.”In this paper, we’re proving it’s possible to use an XFEL to study individual monolayers of protein,” said PNNL microscopist James Evans. “Just being able to see any diffraction is brand new.”Evans co-led the team of two dozen scientists with LLNL physicist Matthias Frank. The bright, fast X-rays were produced at the Linac Coherent Light Source at SLAC National Accelerator Laboratory in Menlo Park, Calif., the newest of DOE’s major X-ray light source facilities at the national laboratories. LCLS, currently the world’s most powerful X-ray laser, is an X-ray free-electron laser. It produces beams millions of times brighter than earlier X-ray light sources.Coming in at around 8 angstrom resolution (which can make out items a thousand times smaller than the width of a hair), the proteins appear slightly blurry but match the expected view based on previous research. Evans said this level of clarity would allow researchers, in some cases, to see how proteins change their shape as they interact with other proteins or molecules in their environment.To get a clearer view of protein monolayers using XFEL, the team will need to improve the resolution to 1 to 3 angstroms, as well as take images of the proteins at different angles, efforts that are currently underway.Not Your Family’s CrystalResearchers have been using X-ray crystallography for more than 60 years to determine the shape and form of proteins that form the widgets and gears of a living organism’s cells. The conventional method requires, however, that proteins stack into a large crystal, similar to how oranges stack in a crate. …

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Increase in obesity may be slowing, but not by much, study shows

In his 2014 State of the Union address, President Barack Obama referred to an August 2013 Centers for Disease Control and Prevention study that showed a decline in the obesity rate among low-income pre-school children, saying, “Michelle’s Let’s Move! partnership with schools, businesses and local leaders has helped bring down childhood obesity rates for the first time in 30 years, and that’s an achievement that will improve lives and reduce health care costs for decades to come.”While the CDC report’s data is encouraging, a new study published by University of Illinois kinesiology and community health professor Ruopeng An shows the notion that the American obesity epidemic has begun to reverse may be premature.The study appears in the journal ISRN Obesity.An said that when the CDC released the report showing declines in obesity among low-income preschool children in 19 of 43 states, it “immediately received a tremendous amount of media attention.””Because people have been fighting the obesity epidemic since the 1980s, this data really looked like a promising sign,” An said. “This triggered my research because I was curious as to whether a similar trend is happening in the adult population.”An turned to the National Health and Nutrition Examination Survey (NHANES) to gather his data. The CDC conducts this nationally representative survey of 5,000 people 20 years of age and older each year, visiting residential areas in a mobile test center. Researchers and physicians examine the participants, collecting objective data such as their height and weight, as well as other health-related statistics.When An examined the Body Mass Index measurements (or BMI, calculated by dividing a person’s weight by his or her height), he found that 71.1 percent of men and 65.6 percent of women in the 2011-2012 NHANES study sample had BMIs greater than or equal to 25, meaning they were overweight or obese. When he compared these levels to those from 2000, he noticed something interesting.”Starting from 2000, the increase in the rate of the prevalence of adult obesity is slowing, but the prevalence is still increasing, especially in those with a BMI higher than 35,” An said. “If you look at those with a BMI greater than 25 — the cutoff point for being overweight — this prevalence only increases slightly over the last 12 years. But those with a BMI greater than 40 — those who are morbidly obese — had the greatest increase in rate compared to the baseline in 2000.”From this data, An believes it is too early to conclude that the prevalence of obesity has begun to level off or even decrease in the United States.”We can’t be naive and underestimate the severity of the obesity epidemic in the U.S. Although there is some preliminary evidence about the decline of obesity prevalence among low income preschoolers, that population is unique; we haven’t gotten good measures for the entire child or adolescent population,” An said. “For the adult population, there are minor declines in the overweight and obesity rate if we compare data from 2012 to that in 2010, but the declines are very small and statistically insignificant. …

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Greenland’s fastest glacier reaches record speeds

Jakobshavn Isbr (Jakobshavn Glacier) is moving ice from the Greenland ice sheet into the ocean at a speed that appears to be the fastest ever recorded. Researchers from the University of Washington and the German Space Agency (DLR) measured the dramatic speeds of the fast-flowing glacier in 2012 and 2013.The results are published today in The Cryosphere, an open access journal of the European Geosciences Union (EGU).”We are now seeing summer speeds more than 4 times what they were in the 1990s on a glacier which at that time was believed to be one of the fastest, if not the fastest, glacier in Greenland,” says Ian Joughin, a researcher at the Polar Science Center, University of Washington and lead-author of the study.In the summer of 2012 the glacier reached a record speed of more than 17 kilometres per year, or over 46 metres per day. These flow rates are unprecedented: they appear to be the fastest ever recorded for any glacier or ice stream in Greenland or Antarctica, the researchers say.They note that summer speeds are temporary, with the glacier flowing more slowly over the winter months. But they add that even the annually averaged speedup over the past couple of years is nearly 3 times what it was in the 1990s.This speedup of Jakobshavn Isbr means that the glacier is adding more and more ice to the ocean, contributing to sea-level rise. “We know that from 2000 to 2010 this glacier alone increased sea level by about 1 mm. With the additional speed it likely will contribute a bit more than this over the next decade,” explains Joughin.Jakobshavn Isbr, which is widely believed to be the glacier that produced the large iceberg that sank the Titanic in 1912, drains the Greenland ice sheet into a deep ocean fjord on the coast of the island. At its calving front, where the glacier effectively ends as it breaks off into icebergs, some of the ice melts while the rest is pushed out, floating into the ocean. Both of these processes contribute about the same amount to sea-level rise from Greenland.As the Arctic region warms, Greenland glaciers such as Jakobshavn Isbr have been thinning and calving icebergs further and further inland. This means that, even though the glacier is flowing towards the coast and carrying more ice into the ocean, its calving front is actually retreating. In 2012 and 2013, the front retreated more than a kilometre further inland than in previous summers, the scientists write in the new The Cryosphere study.In the case of Jakobshavn Isbr, the thinning and retreat coincides with an increase in speed. …

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No joke: Learning the tricks of standup comedy

Oct. 15, 2013 — There is a science to crafting a good bit and delivering a one-liner that sets off a roar of laughter from the audience. And like any skill, Peter Orazem and Gavin Jerome believe it’s one students in their Comedy College course at Iowa State University can learn — no joke, they can learn to be funny.”I get the question all the time, ‘Can you teach someone to be funny? Either you’re funny or you’re not, right?’ No, comedy is like any other skill, like welding, carpentry or brain surgery. There are tricks, techniques and formulas that if you study them, you will be funnier,” said Jerome, a professional entertainer who has partnered with Orazem to teach the course.Orazem, a University Professor of economics at Iowa State University, is living proof. He continues to master the skill he first developed as a student in one of Jerome’s comedy workshops. And he admits his routine has come a long way since learning some of the tricks and techniques of comedy.”I remember the first time, as an academic, my first joke was close to two pages and had footnotes. I learned there’s a difference between a dissertation and a one-liner,” Orazem said.Orazem now gets regular requests to perform at charitable fundraisers and host campus events, like the farewell for former ISU President Gregory Geoffroy. And he uses humor in the classroom, adding punch lines to lectures on microeconomics — a topic few find funny — but Orazem can get a laugh. Jerome said his former student is a great example of how comedy is a tool anyone can use.”Humor is such a universal language; it has practical applications for any student, no matter what field they’re going into,” Jerome said. …

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Osteoporosis a major threat to women’s future independence

Oct. 10, 2013 — According to a new report published by the International Osteoporosis Foundation (IOF), women may expect to live longer but their quality of life will be seriously jeopardized if action to protect their bone health is not taken. Postmenopausal women are the most vulnerable to osteoporosis and fractures. Worldwide, an estimated 200 million women are affected by osteoporosis and around one in three women aged over 50 will suffer from a fracture due to the disease.With an increasingly aging population huge demands will be put on health care systems and on those professionals who provide care within them. In the European Union alone osteoporosis costs €37 billion and with the number of sufferers projected to increase by 23 per cent from 27.5 million in 2010 to 33.9 million in 2025, the costs will continue to escalate. Health care budgets will have to cope with the tsunami of need fueled by age-related chronic diseases in the baby-boomer generation.Professor John A. Kanis, President, IOF urged, “The time to act is now, those of us working in the non-communicable disease (NCD) community congratulated governments for their commitment to reduce the NCD burden by 25 per cent by 2025, at the World Health Assembly in 2012. As advocates for bone, muscle and joint health we have identified cost-effective evidence-based solutions that can be implemented immediately, which will not only save lives but reduce health care costs, and ultimately help governments reach this target.”The report ‘Bone care for the postmenopausal woman’ provides solutions for fracture prevention and management. Given that women over the age of 50 play a critical role as caregivers and breadwinners within the family and society, their bone health is a priority to safeguard future generations. For example, in the US, 43 per cent of caregivers are women aged 50 or over; in Spain 70 per cent of women aged over 65 care for their grandchildren, many every day. …

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Bacteria responsible for gum disease facilitates rheumatoid arthritis

Sep. 12, 2013 — Does gum disease indicate future joint problems? Although researchers and clinicians have long known about an association between two prevalent chronic inflammatory diseases — periodontal disease and rheumatoid arthritis (RA) — the microbiological mechanisms have remained unclear.In an article published today in PLoS Pathogens, University of Louisville School of Dentistry Oral Health and Systemic Diseases group researcher Jan Potempa, PhD, DSc, and an international team of scientists from the European Union’s Gums and Joints project have uncovered how the bacterium responsible for periodontal disease, Porphyromonas gingivalisworsens RA by leading to earlier onset, faster progression and greater severity of the disease, including increased bone and cartilage destruction.The scientists found that P. gingivalis produces a unique enzyme, peptidylarginine deiminanse (PAD) which then enhances collagen-induced arthritis (CIA), a form of arthritis similar to RA produced in the lab. PAD changes residues of certain proteins into citrulline, and the body recognizes citullinated proteins as intruders, leading to an immune attack. In RA patients, the subsequent result is chronic inflammation responsible for bone and cartilage destruction within the joints.Potempa and his team studied another oral bacterium, Prevotella intermedia for the same affect, but learned it did not produce PAD, and did not affect CIA.”Taken together, our results suggest that bacterial PAD may constitute the mechanistic link between P. gingivalis periodontal infection and rheumatoid arthritis, but this ground-breaking conclusion will need to be verified with further research,” he said.Potempa said he is hopeful these findings will shed new light on the treatment and prevention of RA.Studies indicate that compared to the general population, people with periodontal disease have an increased prevalence of RA and, periodontal disease is at least two times more prevalent in RA patients. Other research has shown that a P. gingivalis infection in the mouth will precede RA, and the bacterium is the likely culprit for onset and continuation of the autoimmune inflammatory responses that occur in the disease.

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Back of pack health warnings make little impact on teen smokers

Sep. 4, 2013 — Back of pack picture or text warnings depicting the dangers of smoking, make little impact on teen smokers, particularly those who smoke regularly, suggests research published online in Tobacco Control.Pictorial warnings work better than text alone, but if positioned on the back of the pack are less visible and less effective, say the researchers.In 2008 the UK became the third European Union country to require pictorial health warnings to be carried on the back of cigarette packs.In only five out of the 60 countries worldwide that have introduced this policy do these pictorial warnings cover more than 75% of the main surface areas of a pack, and no European country has adopted the World Health Organization standard of warnings covering half the surface area.The researchers base their findings on the responses of more than a thousand 11 to 16 year olds in the UK, in two waves of the Youth Tobacco Policy Survey in 2008 (1401) and 2011 (1373).The same text warnings appeared on the front and back of packs at both time points, with the only difference being the display of images on the back of packs to support the text warnings in 2011.The teens were quizzed about the visibility and impact of the warnings; how well they served as visual cues; how easy they were to understand and believe; and how persuasive they were. Their responses were scored on a sliding scale from 1 to 5.Most of the respondents in both waves (68-75%) had never smoked; 17-22% had experimented with cigarettes; and around one in 10 were already regular smokers, defined as smoking at least one cigarette every week.Half the respondents in both waves said they had ‘often’ or ‘very often’ noticed the warnings, and around one in five had very often read or looked closely at them. But the percentage of regular smokers who noticed them fell from 77% in 2008 to 66% in 2011.Overall, only one in 10 teens said they thought about the warnings when the pack was not in sight, although never smokers were significantly more likely to think about warnings ‘often’ or ‘very often.’At both time points, most (85%+) teens found the warnings credible, but in 2011 never smokers were less likely to find them easy to understand, while experimental smokers were more likely to find them truthful and believable.And while the proportion of teens who thought the warnings were capable of putting them off smoking and make them less likely to smoke increased between 2008 and 2011, this only applied to never and experimental smokers. There was no change among the regular smokers.Recall of text warnings on the pack front fell between 2008 and 2011, from 58% to 47% (Smoking Kills) and from 41% to 25% (Smoking seriously harms you and others around you), while recall of three images on the back of packs, depicting diseased lungs, rotten teeth and neck cancer, all increased.However, recall of the other back of pack images remained below 10%, and the three text warnings on the back of packs with no supporting images were recalled by less than 1% at either time point.The proportion of teens who said they hid the cigarette pack from others increased significantly between 2008 and 2011, but there was no increase in other avoidant behaviours. And among regular smokers, the proportion who said that the warnings stopped them from having a cigarette fell from 32% to 23%.”As warnings need to be salient to be effective, positioning pictorial warnings only on the less visible reverse panel limits their impact,” write the authors. “While recall was high at both waves for pack-front warnings, it was low (below 10%) for the pictorial warnings on the pack reverse, fear-appeal pictures aside,” they add.The fact that the UK has used the same pictures since 2008 may also have increased the “wear out” factor, particularly for regular smokers, say the authors.”Positioning pictorial warnings only on the back of packs may have had a deterrent effect on never and experimental smokers, but for most measures no significant differences were observed. The impact on regular smokers was negligible,” they conclude.

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The science of collaboration

Aug. 28, 2013 — It’s a long, expensive, risky road to turn a scientific breakthrough into a treatment that can help patients. Fewer organizations are trying to tackle the challenges alone, says a new paper from MIT researchers published August 28 in the journal Science Translational Medicine.An essential new way to move discoveries forward has emerged in the form of multi-stakeholder collaborations involving three or more different types of organizations, such as drug companies, government regulators and patient groups, write Magdalini Papadaki, a research associate, and Gigi Hirsch, a physician-entrepreneur and executive director of the MIT Center for Biomedical Innovation.The authors are calling for a new “science of collaboration” to learn what works and doesn’t work; to improve how leaders can design, manage and evaluate collaborations; and to help educate and train future leaders with the necessary organizational and managerial skills.”Getting new, better, affordable drugs to the right patients faster involves a series of historically independent decisions made by different players or stakeholders,” says Hirsch. The system is uncoordinated, takes too long, and costs too much. In some cases, the drug — such as new antibiotics for life-threatening resistant infections — may never become available.”One of the interesting paradoxes of biomedical innovation is increasingly going to be that even though we have the scientific knowledge required to provide potentially better treatments for patients — or even to prevent disease in those who are at high risk — we may be unable to help patients benefit from them anytime soon,” she says.To help change this scenario, in the last decade, thousands of researchers, pharmaceutical and biotechnology companies, government regulators, payers, clinicians and patients have come together in more than 100 multi-stakeholder collaborations to solve some specific shared problem standing in the way of finding a cure or a better diagnostic approach.”Multi-stakeholder collaborations provide the opportunity to create an environment that allows for new kinds of interactions among the players,” Hirsch says. The largest multi-stakeholder effort, the European Union’s Innovative Medicines Initiative (IMI) began in 2008 and has established more than 40 consortia with financial and in-kind investments totaling €2 billion. Some projects focus on specific health issues, such as Alzheimer’s disease, chronic pain, diabetes and obesity. Others tackle bigger issues, such as drug and vaccine safety and the use of stem cells for drug discovery. The success has led to a proposal to extend the effort for 10 years and €3.5 billion. Last year, the U.S. …

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New and remarkable details of the sun

Aug. 6, 2013 — Researchers at NJIT’s Big Bear Solar Observatory (BBSO) in Big Bear, CA have obtained new and remarkably detailed photos of the Sun with the New Solar Telescope (NST). The photographs reveal never-before-seen details of solar magnetism revealed in photospheric and chromospheric features.”With our new generation visible imaging spectrometer (VIS),” said Wenda Cao, NJIT Associate Professor of Physics and BBSO Associate Director, “the solar atmosphere from the photosphere to the chromosphere, can be monitored in a near real time. One image was taken with VIS on May 22, 2013 in H-alpha line center. The lawn-shaped pattern illustrates ultrafine magnetic loops rooted in the photosphere below.”The other photospheric photograph is the most precise sunspot image ever taken: A textbook sunspot that looks like a daisy with many petals. The dark core of the spot is the umbra and the petals are the penumbra. “With the unprecedented resolution of BBSO’s NST, many previously unknown small-scale sunspot features can now be perceived,” said Cao. In particular, there are the twisting flows along the penumbra’s less dark filaments, the complicated dynamic motion in the light bridge vertically spanning the umbra’s darkest part and the dark cores of the small bright points or umbra dots.BBSO has been under NJIT’s management since 1997 when NJIT took over the facility from California Institute of Technology. The founder and executive director has been NJIT Distinguished Professor Philip R. Goode, a Fellow of the American Physical Society and the American Association for the Advancement of Science and the American Geophysical Union.Goode led the project, which was completed in 2009, to build the world’s most capable solar telescope at BBSO. …

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How do student characteristics predict university graduation odds?

July 31, 2013 — In his January 2009 State of the Union address, President Obama announced his goal for the U.S. to lead the world in college graduates by 2020. While policymakers often blame university systems for low graduation among college students, according to new research, characteristics known about a student before he or she even enters a college classroom can accurately predict graduation rates. This new study, published in SAGE Open, finds that characteristics such as fulltime enrollment status, race, transfer credits, and expected family contribution predict successful graduation from college.Researcher Tim Gramling, LP.D., conducted research on characteristics of more than 2,500 students from the full population of one large, for-profit university and found that higher GPA, fulltime enrollment status, black race (over whites), a higher number of transfer credits when enrolling, and higher expected family contribution weighed most heavily in accurately predicting higher graduation odds.Taken together, these five characteristics predict graduation rates with 86.9% accuracy, despite the fact that federal policy has worked under the assumption that tax status of an institution is the primary determinant of student graduation (i.e., non-profit v. for-profit). Additionally, when GPA is removed as one of the predicting factors, the remaining four characteristics (determined before a student even begins his or her studies), still predict graduation rates with 74.3% accuracy.”The findings of this study challenge the traditional assumptions for improving university graduation rates. Because student characteristics have such a dramatic impact on graduation odds, changing federal tax status of a university would have little positive impact on graduation,” Gramling stated.Gramling offered different ways to improve graduation rates based on his findings, “Policymakers could increase funding for lower income students which would mitigate the need for expected family contribution and provide incentives for them to attend school full time — both factors that have shown accurately predict higher graduation odds.”The findings of the study also had implications for traditional methods for rewarding higher GPAs. Since the study found that black students were more likely than white students to graduate, especially if they had a GPA between a 2.0 and a 2.5, public policy that rewards high GPAs and punishes low GPAs would disproportionately impact black students.Gramling continued, “As blacks exhibited higher odds of graduating than whites at this campus, the U.S. Department of Education should explore how for-profit institutions can benefit black students, especially as other research does not suggest that blacks have higher (or even equal) odds of graduating than whites at traditional institutions.”

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Solitary lemurs avoid danger with a little help from the neighbors

July 5, 2013 — An endangered species of Madagascan lemur uses the alarm calls of birds and other lemurs to warn it of the presence of predators, a new study by researchers from the University of Bristol and Bristol Zoo with the University of Torino has found. This is the first time this phenomenon has been observed in a solitary and nocturnal lemur species.Very little is known about the Sahamalaza sportive lemur (Lepilemur sahamalazensis), other than the fact it roosts during the day in rather open situations, such as tree holes, and therefore risks falling victim to predators from both the air and the ground.Sportive lemurs are not kept in any zoo. Prior to this research virtually nothing was known about this particular species despite the fact that it has been classified as Critically Endangered, the top threat category of the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species, at a red-listing workshop in Madagascar in July 2012.Dr Melanie Seiler, a researcher at Bristol Zoo and the University of Bristol, and lead author of the study, said: “We were seeking any information we could gather that could help us understand this species better, with the objective of improving targeted conservation efforts.”One of the problems of small nocturnal species is that they don’t get a great deal of scientific or conservation attention. The Sahamalaza sportive lemur doesn’t have striking blue eyes like blue-eyed black lemurs or any other unusual features. That means that no-one had really looked into what these animals need to survive.”Dr Marc Holderied of the University of Bristol said: “Until our study, a solitary and nocturnal lemur species had never been tested to see if it could understand other species’ alarm calls and differentiate between them. We were also the first to test any species of lemur to see if it could recognise the alarm calls of a non-primate species.”The researchers found that the vigilance of sportive lemurs significantly increased after they heard playbacks of the alarm calls of the crested coua and the Madagascar magpie-robin. They also responded with increased vigilance to the aerial alarm calls of the blue-eyed black lemur, scanning towards the sky but never the ground which suggests they classified the alarm call correctly.Dr Holderied said: “Our results indicate that the Sahamalaza sportive lemur is capable of gleaning information on predator presence and predator type from the referential signals of different surrounding species. Examples for cross-species semantics in lemurs are rare, and this is the first record of lemurs using information across vertebrate classes.”The lemurs of Sahamalaza National Park in northwest Madagascar are threatened by deforestation, hunting and forest fragmentation. Bristol Zoo is working to preserve the small bits of forest, roughly 200 hectares on the Sahamalaza Peninsula, that they have left which is vitally important for the continued survival of this and other lemur species.

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Names for new Pluto moons accepted

July 2, 2013 — The IAU is pleased to announce that today it has officially recognised the names Kerberos and Styx for the fourth and fifth moons of Pluto respectively (formerly known as P4 and P5). These names were backed by voters in a recently held popular contest, aimed at allowing the public to suggest names for the two recently discovered moons of the most famous dwarf planet in the Solar System.The new moons were discovered in 2011 and 2012, during observations of the Pluto system made with the NASA/ESA Hubble Space Telescope Wide Field Camera 3, and increasing the number of known Pluto moons to five. Kerberos lies between the orbits of Nix and Hydra, two bigger moons discovered by Hubble in 2005, and Styx lies between Charon, the innermost and biggest moon, and Nix. Both have circular orbits assumed to be in the plane of the other satellites in the system. Kerberos has an estimated diameter of 13 to 34 kilometres, and Styx is thought to be irregular in shape and is 10 to 25 kilometres across.The IAU acts as the arbiter of the naming process of celestial bodies, and is advised and supported by astronomers active in different fields. On discovery, astronomical objects receive unambiguous and official catalogue designations. When common names are assigned, the IAU rules ensure that the names work across different languages and cultures in order to support collaborative worldwide research and avoid confusion.After the discovery, the leader of the research team, Mark Showalter (SETI Institute), decided to call for a public vote to suggest names for the two objects. To be consistent with the names of the other Pluto satellites, the names had to be picked from classical mythology, in particular with reference to the underworld — the realm where the souls of the deceased go in the afterlife. The contest concluded with the proposed names Vulcan, Cerberus and Styx ranking first, second and third respectively. Showalter submitted Vulcan and Cerberus to the IAU where the Working Group for Planetary System Nomenclature and the Committee on Small Body Nomenclature discussed the names for approval.However, the name Vulcan had already been used for a hypothetical planet between Mercury and the Sun. …

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Overweight causes heart failure: Large study with new method clarifies the association

June 25, 2013 — An international research team led by Swedish scientists has used a new method to investigate obesity and overweight as a cause of cardiovascular disease. Strong association have been found previously, but it has not been clear whether it was overweight as such that was the cause, or if the overweight was just a marker of another underlying cause, as clinical trials with long-term follow-ups are difficult to implement.A total of nearly 200,000 subjects were included in the researchers’ study of the causality between obesity/overweight and diseases related to cardiovascular conditions and metabolism, which is being published for the first time in PLOS Medicine. The goal was to determine whether obesity as such is the actual cause of these diseases or whether obesity is simply a marker of something else in the subject’s lifestyle that causes the disease.”We knew already that obesity and cardiovascular disease often occur together. However, it has been hard to determine whether increased BMI as such is dangerous. In this study we found that individuals with gene variants that lead to increased body-mass index (BMI) also had an increased risk of heart failure and diabetes. The risk of developing diabetes was greater than was previously thought,” says Tove Fall, a researcher at the Department of Medical Sciences and the Science for Life Laboratory, Uppsala University, who coordinated the study together with researchers from the Karolinska Institutet and Oxford University.These scientists studied whether a gene variant in the FTO gene, which regulates the appetite and thereby increases the individual’s BMI, is also linked to a series of cardiovascular diseases and metabolism. The risk variant is common in the population, and each copy of the risk variant increases BMI by an average of 0.3-0.4 units. Since an individual’s genome is not affected by lifestyle and social factors, but rather is established at conception, when the embryo randomly receives half of each parent’s genome, the method is thus called “Mendelian randomization.” To achieve reliable results a large study material was needed, and nearly 200,000 individuals from Europe and Australia participated.”Epidemiological studies look for associations in large populations, but it is usually difficult to reliably determine cause and effect — what we call causality. By using this new genetic method, Mendelian randomization, in our research, we can now confirm what many people have long believed, that increased BMI contributes to the development of heart failure. We also found that overweight causes increases in liver enzymes . …

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Transistor made from just one molecular monolayer made to work on computer chip

June 20, 2013 — Electronic components built from single molecules using chemical synthesis could pave the way for smaller, faster and more green and sustainable electronic devices. Now for the first time, a transistor made from just one molecular monolayer has been made to work where it really counts. On a computer chip.The molecular integrated circuit was created by a group of chemists and physicists from the Department of Chemistry Nano-Science Center at the University of Copenhagen and Chinese Academy of Sciences, Beijing. Their discovery has just been published online in the periodical Advanced Materials. The breakthrough was made possible through an innovative use of the two dimensional carbon material graphene.First step towards integrated molecular circuitKasper Nørgaard is an associate professor in chemistry at the University of Copenhagen. He believes that the first advantage of the newly developed graphene chip will be to ease the testing of coming molecular electronic components. But he is also confident, that it represents a first step towards proper integrated molecular circuits.”Graphene has some very interesting properties, which cannot be matched by any other material.What we have shown for the first time is that it’s possible to integrate a functional component on a graphene chip. I honestly feel this is front page news,” says Nørgaard.See through sandwich central to functionThe molecular computer chip is a sandwich built with one layer of gold, one of molecular components and one of the extremely thin carbon material graphene. The molecular transistor in the sandwich is switched on and of using a light impulse so one of the peculiar properties of graphene is highly useful. Even though graphene is made of carbon, it’s almost completely translucent.Environmentally important. …

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Rapid change in China brings significant improvements in health

June 6, 2013 — China made substantial gains in health over the past two decades, including increases in life expectancy, reductions in child mortality, and declines in infectious diseases such as tuberculosis and lower respiratory infections. But with that success accompanies the growth of non-communicable diseases and risk factors such as tobacco use and high blood pressure, which could overwhelm the health system.These are some of the findings published June 8 in The Lancet in an analysis by the Chinese Center for Disease Control and Prevention, Peking Union Medical College and the Institute for Health Metrics and Evaluation (IHME).The data are drawn from the Global Burden of Diseases, Injuries, and Risk Factors Study 2010 (GBD 2010), a collaborative project of researchers worldwide led by IHME at the University of Washington. The paper compares China to countries in the G20, underscoring the fast-moving pace of health change in China and how it now looks more like the US, UK, or Australia in some respects. China’s rate of premature mortality in 2010, for example, was only slightly higher than in the US and lower than all emerging economies in the G20 when accounting for changes in population age.Looking back to 1990, China had a health profile very similar to much of the developing world, including countries such as Vietnam or Iraq. The leading causes of health loss in China in 1990 were chronic pulmonary obstructive disease (COPD), lower respiratory infections, stroke, congenital anomalies, and neonatal encephalopathy. By 2010, though, the picture had changed in important ways. The main causes of health loss were stroke, ischemic heart disease, COPD, low back pain, and road injury.Although Chinese women have one of the lowest rates of smoking prevalence in the world, men in China have one of the highest at 52% and exposure to second-hand smoke is as high as 72%.”Tobacco is one of the top three risk factors in China and deaths attributable to its use have increased by almost 30% since 1990. Aggressive tobacco control measures will be an important public health effort,” said Dr. Gonghuan Yang, professor at Peking Union Medical College and a joint lead author of the China GBD paper.In addition to tobacco use, dietary risks and high blood pressure were the other leading risk factors in China in 2010, followed by ambient air pollution and household air pollution. As the proportion of disease attributable to diet and other individual behaviors increases, non-communicable disease has increased as well.”Urbanization and aging are two of the driving forces behind the rise of non-communicable disease. …

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Clenbuterol in livestock farming may affect results of doping controls in sport

Apr. 17, 2013 — The illegal use of clenbuterol in livestock farming may affect the results of doping controls in sport. This is the conclusion of a study by the Institute of Food Safety, RIKILT Wageningen UR, Netherlands, in partnership with fellow institutes.


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At the behest of FIFA (Fédération Internationale de Football Association), RIKILT examined 47 meat and food samples. All originated from hotels in Mexico where football teams stayed during the U-17 World Cup. In 14 of these samples, the growth promoter clenbuterol was found.

A different institute studied 208 urine samples from footballers staying at the hotels in question and found clenbuterol in 109 of them. Only five of the 24 teams which had provided urine samples tested negative for the presence of clenbuterol. At least one of those teams had been put on a strict non-meat diet.

FIFA launched its investigation into possible problems with food contamination in connection with doping tests in 2011, prompted by five positive doping tests involving clenbuterol in members of the Mexican national football team during out-of-competition doping tests.

The study demonstrates that clenbuterol in meat for human consumption causes major problems when eaten by top athletes who are registered in national and international doping control systems. As such, there is an urgent need for government action to combat the illegal use of clenbuterol in livestock farming worldwide.

Banned

The use of clenbuterol in livestock farming is banned in the entire European Union. This prohibition also applies to all meat exporting countries selling meat products in the markets of the EU member states.

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Story Source:

The above story is reprinted from materials provided by Wageningen University and Research Centre.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. Mario Thevis, Lina Geyer, Hans Geyer, Sven Guddat, Jiri Dvorak, Anthony Butch, Saskia S. Sterk, Wilhelm Schänzer. Adverse analytical findings with clenbuterol among U-17 soccer players attributed to food contamination issues. Drug Testing and Analysis, 2013; DOI: 10.1002/dta.1471

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Europe needs genetically engineered crops, scientists say

Apr. 25, 2013 — The European Union cannot meet its goals in agricultural policy without embracing genetically engineered crops (GMOs). That’s the conclusion of scientists who write in Trends in Plant Science, a Cell Press publication, based on case studies showing that the EU is undermining its own competitiveness in the agricultural sector to its own detriment and that of its humanitarian activities in the developing world.

“Failing such a change, ultimately the EU will become almost entirely dependent on the outside world for food and feed and scientific progress, ironically because the outside world has embraced the technology which is so unpopular in Europe, realizing this is the only way to achieve sustainable agriculture,” said Paul Christou of the University of Lleida-Agrotecnio Center and Institució Catalana de Recerca i Estudis Avançats in Spain.

“Many aspects of the EU agricultural policy, including those concerning GMOs, are internally inconsistent and actively obstruct what the policy sets out to achieve,” Christou and his colleagues continued.

For instance, the Lisbon Strategy aims to create a knowledge-based bioeconomy and recognizes the potential of GMOs to deliver it, but EU policy on the cultivation of GMOs has created an environment that makes this impossible. In reality, there is a de facto moratorium in Europe on the cultivation of genetically engineered crops such as maize, cotton, and soybean, even as the same products are imported because there is insufficient capacity to produce them by conventional means at home.

Subsidies designed to support farmers now benefit large producers at the expense of family farms, Christou says. The EU has also banned its farmers from using many pesticides and restricted them from other nonchemical methods of pest control, while allowing food products produced in the same ways to be imported.

“EU farmers are denied freedom of choice — in essence, they are prevented from competing because EU policies actively discriminate against those wishing to cultivate genetically engineered crops, yet exactly the same crops are approved for import,” Christou says.

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