Carbon loss from soil accelerating climate change

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

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Take the bat, leave the candy: The food environment of youth baseball

‘Take me out to the ballgame’ doesn’t exactly conjure up images of apple slices and kale chips. The more likely culprits include French fries, soda and the occasional box of Crackerjacks.Unfortunately for children who play youth baseball, eating unhealthy food during practices and games may be contributing to weight problems, according to researchers at Wake Forest Baptist Medical Center. The study, published in the current online edition of Childhood Obesity, found that high-calorie snacks and sugar-sweetened drinks dominate the youth baseball scene.“Though youth sports are an excellent way to promote physical activity, social interaction and positive health behaviors, the food environments are often characterized by less healthy food options with high calorie contents and lower nutrient density,” said Joseph Skelton, M.D., associate professor of pediatrics at Wake Forest Baptist and senior author of the study.In this observational study, the research team conducted an environmental scan of foods consumed by players and family members during 12 games at a youth baseball field in northwest North Carolina. The players were boys 8 to 11 years old on six teams.The researchers found that most snacks were high-calorie food items, including French fries, candy and cookies and most beverages were sugar-sweetened. Nearly 90 percent of food and beverage items purchased were from the concession stand.“Team sports like baseball are still very important for children’s activity and development,” said Megan Irby, M.S, co-author and research program manager of Brenner FIT, a multidisciplinary pediatric obesity program at Wake Forest Baptist.“But as seen in this study, games and practices can be upwards of two to three nights a week, and many children participate on multiple sports teams each year. Parents should plan ahead for these busy times and even advocate in their local sports leagues for policies that address snacks and drinks.”This research was the first step in exploring the question of whether children and families attending youth sporting events may be increasing their risk for being overweight or obese as a result of chronic unhealthy food behaviors associated with sports participation, Skelton said. Contrary to the intent of youth sports, these findings indicate that children may be leaving the ball field having consumed more calories than they expended.“Despite the benefits of participating in sports, the increased exposure to unhealthy foods and disruption of meal times may increase children’s risk for poor nutritional habits that can contribute to weight management issues,” Skelton said.A limitation of the study was the ability to accurately document all foods consumed at the ballpark without being intrusive.Story Source:The above story is based on materials provided by Wake Forest Baptist Medical Center. Note: Materials may be edited for content and length.

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Male or female? First sex-determining genes appeared in mammals some 180 million years ago

Man or woman? Male or female? In humans and other mammals, the difference between sexes depends on one single element of the genome: the Y chromosome. It is present only in males, where the two sexual chromosomes are X and Y, whereas women have two X chromosomes. Thus, the Y is ultimately responsible for all the morphological and physiological differences between males and females.But this has not always been the case. A very long time ago, the X and Y were identical, until the Y started to differentiate from the X in males. It then progressively shrank to such an extent that, nowadays, it only contains about 20 genes (the X carries more than one thousand genes). When did the Y originate and which genes have been kept? The answer has just been brought to light by the team of Henrik Kaessmann, Associate Professor at the CIG (UNIL) and group leader at the SIB Swiss Institute of Bioinformatics, and their collaborators in Australia. They have established that the first ” sex genes ” appeared concomitantly in mammals around 180 million years ago.4,3 billion genetic sequencesBy studying samples from several male tissues — in particular testicles — from different species, the researchers recovered the Y chromosome genes from the three major mammalian lineages: placentals (which include humans, apes, rodents and elephants), marsupials (such as opossums and kangaroos) and monotremes (egg-laying mammals, such as the platypus and the echidna, a kind of Australian porcupine). …

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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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Cyber buddy is better than ‘no buddy’

A Michigan State University researcher is looking to give exercise enthusiasts the extra nudge they need during a workout, and her latest research shows that a cyber buddy can help.The study, which appears in the Games for Health Journal, is the first to indicate that although a human partner is still a better motivator during exercise, a software-generated partner also can be effective.”We wanted to demonstrate that something that isn’t real can still motivate people to give greater effort while exercising than if they had to do it by themselves,” said Deborah Feltz, a University Distinguished Professor in MSU’s kinesiology department who led the study with co-investigator Brian Winn, associate professor in MSU’s College of Communication Arts and Sciences.The implications from the research also could open the door for software and video game companies to create cyber buddy programs based on sport psychology.”Unlike many of the current game designs out there, these results could allow developers to create exercise platforms that incorporate team or partner dynamics that are based on science,” said Feltz.Using “CyBud-X,” an exercise game specifically developed for Feltz’s research, 120 college-aged participants were given five different isometric plank exercises to do with one of three same-sex partner choices.Along with a human partner option, two software-generated buddies were used — one representing what looked to be a nearly human partner and another that looked animated. The participant and partner image were then projected onto a screen via a web camera while exercising.The results showed that a significant motivational gain was observed in all partner conditions.”Even though participants paired with a human partner held their planks, on average, one minute and 20 seconds longer than those with no partner, those paired with one of the software-generated buddies still held out, on average, 33 seconds longer,” said Feltz.Much of Feltz’s research in this area has focused on the Khler Motivation Effect, a phenomenon that explains why people, who may not be adept exercisers themselves, perform better with a moderately better partner or team as opposed to working out alone.Her findings give credence that programs such as “CyBud-X” can make a difference in the way people perform.”We know that people tend to show more effort during exercise when there are other partners involved because their performance hinges on how the entire team does,” she said. “The fact that a nonhuman partner can have a similar effect is encouraging.”Story Source:The above story is based on materials provided by Michigan State University. Note: Materials may be edited for content and length.

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Scientists report success growing cartilage to reconstruct nostrils and implanting tissue-engineered vaginal organs into humans

Two new articles published in The Lancet report the first ever successful operations in humans to reconstruct the alar wings of the nose (nostrils) (Martin et al), and to implant tissue-engineered vaginal organs in women with a rare syndrome that causes the vagina to be underdeveloped or absent (Atala et al), in both cases using the patients’ own tissue.In one paper, led by Professor Ivan Martin from the University of Basel in Switzerland, scientists report having engineered a human cartilage graft from patients’ own nasal septum cartilage cells to successfully rebuild the nostrils (alar lobule) of five individuals whose noses were damaged by skin cancer. One year after reconstruction, all five recipients were satisfied with their ability to breathe, as well as the cosmetic appearance of their nose, and did not report any local or systemic adverse events.The nose is the most common site of non-melanoma skin cancer, because of its cumulative exposure to sunlight, with the highest frequency of cancer occurring on the alar lobule. Currently, when removing skin cancers, surgeons often have to cut away parts of cartilage, (for instance from the nasal septum, ear, or rib) as grafts to functionally reconstruct the tumour excision site. However, this painful and invasive procedure involves major additional surgery, and has been associated with complications at the site from which cartilage has been removed.A team from the University of Basel, Switzerland, investigated an alternative approach using engineered cartilage tissue grown from patients’ own cells. They extracted the cartilage cells (chondrocytes) from the nasal septum of each patient, and multiplied the cells by exposing them to growth factors for two weeks. The expanded cells were seeded onto collagen membranes and cultured for two additional weeks, generating cartilage 40 times larger than the original biopsy. When the engineered grafts were ready they were shaped according to the defect and implanted.According to Professor Martin, “The engineered cartilage had clinical results comparable to the gold standard cartilage graft surgery. This new technique could help the body accept the new tissue more easily, and improve the stability and functionality of the nostril. Our success is based on the long-standing, effective integration in Basel between our experimental group at the Department of Biomedicine and the surgical disciplines. It opens the way to using this engineered cartilage for more challenging reconstructions in facial surgery such as the complete nose, eyelid, or ear. …

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Positive outcomes for hepatitis C transplant patients

New research announced at the International Liver CongressTM 2014 today provides new hope for the notoriously difficult-to-treat population of liver transplant patients with recurring hepatitis C (HCV).As part of a compassionate use program, 104 post-liver transplant patients with recurring HCV who had exhausted all treatment options and had poor clinical prognoses, received sofosbuvir (SOF) and ribavirin (RBV) with pegylated interferon (PEG) included at the physicians’ discretion for up to 48 weeks. Among patients whose clinical outcomes have been reported, 62% achieved SVR12. Additionally, 62% of patients had improvements in clinical conditions associated with hepatic decompensation (e.g., ascites and encephalopathy) and/or improvement in liver function tests. SOF+RBVPEG was well-tolerated and led to high rates of virologic suppression.EASL’s European Policy Councillor Professor Patrizia Burra of the Multivisceral Transplant Unit, Padova University Hospital, Padua, Italy said: “There are currently no effective treatment options for this patient group. However, this new trial involving the nucleotide polymerase inhibitor sofosbuvir (SOF) has demonstrated promising results, providing further evidence of its clinical potential.””For patients with advanced hepatitis C liver disease, liver transplants offer a second chance,” continued Professor Burra, “and for those who continue to suffer post-surgery, it’s important for us to keep following up all avenues possible to improve their quality of life.”Other research revealed at the International Liver CongressTM 2014 showed that most patients with mild hepatitis C recurrence diagnosed one year after liver transplant have excellent long-term outcomes.In the second study, 172 patients who were diagnosed with mild hepatitis C recurrence one year after undergoing liver transplant surgery between 1999 and 2012 were followed for six and a half years with all relevant transplant-related, donor and recipient variables recorded. The cumulative probability of HCV-related graft loss five and 10 years after liver transplant were 3% and 10%, respectively.However one third of these patients are still at risk of going on to develop cirrhosis, further demonstrating the need for antiviral therapy pre or post-transplant.Hepatitis C infection is a common cause of liver transplantation, with virus-related diseases comprising 40% of primary indications for liver transplantation in Europe among patients with cirrhosis.More than 5,500 liver transplantations are currently performed in Europe per year.Story Source:The above story is based on materials provided by European Association for the Study of the Liver. Note: Materials may be edited for content and length.

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Protein researchers closing in on the mystery of schizophrenia

Schizophrenia is a severe disease for which there is still no effective medical treatment. In an attempt to understand exactly what happens in the brain of schizophrenic people, researchers from the University of Southern Denmark have analysed proteins in the brains of rats that have been given hallucinogenic drugs. This may pave the way for new and better medicines.Seven per cent of the adult population suffer from schizophrenia, and although scientists have tried for centuries to understand the disease, they still do not know what causes the disease or which physiological changes it causes in the body. Doctors cannot make the diagnosis by looking for specific physiological changes in the patient’s blood or tissue, but have to diagnose from behavioral symptoms.In an attempt to find the physiological signature of schizophrenia, researchers from the University of Southern Denmark have conducted tests on rats, and they now believe that the signature lies in some specific, measurable proteins. Knowing these proteins and comparing their behavior to proteins in the brains of not-schizophrenic people may make it possible to develop more effective drugs.It is extremely difficult to study brain activity in schizophrenic people, which is why researchers often use animal models in their strive to understand the mysteries of the schizophrenic brain. Rat brains resemble human brains in so many ways that studying them makes sense if one wants to learn more about the human brain.Schizophrenic symptoms in ratsThe strong hallucinogenic drug phenocyclidine (PCP), also known as “angel’s dust,” provides a range of symptoms in people which are very similar to schizophrenia.”When we give PCP to rats, the rats become valuable study objects for schizophrenia researchers,” explains Ole Nrregaard Jensen, professor and head of the Department of Biochemistry and Molecular Biology.Along with Pawel Palmowski, Adelina Rogowska-Wrzesinska and others, he is the author of a scientific paper about the discovery, published in the international Journal of Proteome Research.Among the symptoms and reactions that can be observed in both humans and rats are changes in movement and reduced cognitive functions such as impaired memory, attention and learning ability.”Scientists have studied PCP rats for decades, but until now no one really knew what was going on in the rat brains at the molecular level. We now present what we believe to be the largest proteomics data set to date,” says Ole Nrregaard Jensen.PCP is absorbed very quickly by the brain, and it only stays in the brain for a few hours. Therefore, it was important for researchers to examine the rats’ brain cells soon after the rats were injected with the hallucinogenic drug.”We could see changes in the proteins in the brain already after 15 minutes. And after 240 minutes, it was almost over,” says Ole Nrregaard Jensen.The University of Southern Denmark holds some of the world’s most advanced equipment for studying proteins, and Ole Nrregaard Jensen and his colleagues used the university’s so-called mass spectrometres for their protein studies.352 proteins cause brain changes”We found 2604 proteins, and in 352 of them, we saw changes that can be associated with the PCP injections. These 352 proteins will be extremely interesting to study in closer detail to see if they also alter in people with schizophrenia — and if that’s the case, it will of course be interesting to try to develop a drug that can prevent the protein changes that lead to schizophrenia,” says Ole Nrregaard Jensen about the discovery and the work that now lies ahead.The 352 proteins in rat brains responded immediately when the animals were exposed to PCP. …

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Putting a price on ecological restoration

Putting a price on clean water and soil fertility helps the UN set ecological restoration targets for degraded and deforested land.Forests provide essential ecosystem services for people, including timber, food and water. For those struggling with the after-effects of deforestation, the main hope lies in rebuilding forest resources through ecological restoration.Researchers at BU have shown that placing a monetary value on ecosystem services provides a mechanism for evaluating the costs and benefits of reforestation activity.”Ecological restoration initiatives are being undertaken around the world, attracting investment of $US billions annually,” explained Professor Adrian Newton. “They make a significant contribution to sustainable development but few attempts have been made to systematically evaluate their effectiveness.”To address this knowledge gap, Professor Newton and fellow BU researchers analysed 89 different types of restored ecosystem sites across the world. The results showed that, although restored land was not as productive as land that had not been degraded, restoration efforts increased biodiversity by 44% and provision of ecosystem services by 25%.What’s unique about Professor Newton’s research is that it also provides one of the first evidence-based assessments of how cost-effective ecological restoration initiatives actually are.Professor Newton developed this method as part of the ReForLan research project in the dryland forests of Latin America. ReForLAn brought together researchers from six countries to assess the environmental degradation and the potential for ecological recovery through restoration.The methodology assigns financial value to ecosystem services, such as the provision of clean water, carbon storage and soil fertility that would result from restoration, thereby demonstrating how cost effective these efforts are.”We examined whether ecological restoration can be cost effective, based on the value of ecosystem services provided by restoration actions,” he explained. “This was undertaken by analysing the value of the increased provision of ecosystem services that could potentially be provided as a result of ecological restoration actions.”So successful is the methodology that it was used to inform the United Nations Environment Programme’s restoration targets and specifically ‘Target 15’ of the Aichi Biodiversity Targets to restore 15% of the world’s degraded ecosystems by 2020.The UN say these targets can be achieved through Forest Landscape Restoration, which is an approach developed, tested and refined by Professor Newton during the ReForLan project.”We examined how Forest Landscape Restoration may be implemented in practice, and evaluated the cost effectiveness of this approach and its benefit to human communities,” he explained.Professor Newton has demonstrated that at the heart of successful forest landscape restoration is a flexible and adaptive approach. It should allow communities to participate in the decision-making process, and enhance ecosystem service provision for those living within them.The Forest Landscape Restoration method has been heralded as the solution to restoring 150 million acres of degraded and deforested land. This target is part of a global movement, known as ‘Bonn Challenge’, named from its inception in Bonn, Germany in 2011. Individual countries have so far committed to restoring 50 million hectares of forest, which is a significant step towards achieving the policy goals.”This initiative directly employs the Forest Landscape Restoration approach that we researched, developed, tested and refined,” explains Professor Newton.He conclude, “Ecosystems are a rich source of biodiversity and the services they provide are relied upon by local people. The approach developed through the ReForLan project allows policy makers to identify locations where ecological restoration is most likely to be cost effective.”ReForLan was funded by the European Commission and the full title of the project is ‘Restoration of Forest Landscapes for Biodiversity Conservation and Rural Development’.Story Source:The above story is based on materials provided by Bournemouth University. …

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Food quality will suffer with rising carbon dioxide, field study shows

For the first time, a field test has demonstrated that elevated levels of carbon dioxide inhibit plants’ assimilation of nitrate into proteins, indicating that the nutritional quality of food crops is at risk as climate change intensifies.Findings from this wheat field-test study, led by a UC Davis plant scientist, will be reported online April 6 in the journal Nature Climate Change.”Food quality is declining under the rising levels of atmospheric carbon dioxide that we are experiencing,” said lead author Arnold Bloom, a professor in the Department of Plant Sciences.”Several explanations for this decline have been put forward, but this is the first study to demonstrate that elevated carbon dioxide inhibits the conversion of nitrate into protein in a field-grown crop,” he said.The assimilation, or processing, of nitrogen plays a key role in the plant’s growth and productivity. In food crops, it is especially important because plants use nitrogen to produce the proteins that are vital for human nutrition. Wheat, in particular, provides nearly one-fourth of all protein in the global human diet.Many previous laboratory studies had demonstrated that elevated levels of atmospheric carbon dioxide inhibited nitrate assimilation in the leaves of grain and non-legume plants; however there had been no verification of this relationship in field-grown plants.Wheat field studyTo observe the response of wheat to different levels of atmospheric carbon dioxide, the researchers examined samples of wheat that had been grown in 1996 and 1997 in the Maricopa Agricultural Center near Phoenix, Ariz.At that time, carbon dioxide-enriched air was released in the fields, creating an elevated level of atmospheric carbon at the test plots, similar to what is now expected to be present in the next few decades. Control plantings of wheat were also grown in the ambient, untreated level of carbon dioxide.Leaf material harvested from the various wheat tests plots was immediately placed on ice, and then was oven dried and stored in vacuum-sealed containers to minimize changes over time in various nitrogen compounds.A fast-forward through more than a decade found Bloom and the current research team able to conduct chemical analyses that were not available at the time the experimental wheat plants were harvested.In the recent study, the researchers documented that three different measures of nitrate assimilation affirmed that the elevated level of atmospheric carbon dioxide had inhibited nitrate assimilation into protein in the field-grown wheat.”These field results are consistent with findings from previous laboratory studies, which showed that there are several physiological mechanisms responsible for carbon dioxide’s inhibition of nitrate assimilation in leaves,” Bloom said.3 percent protein decline expectedBloom noted that other studies also have shown that protein concentrations in the grain of wheat, rice and barley — as well as in potato tubers — decline, on average, by approximately 8 percent under elevated levels of atmospheric carbon dioxide.”When this decline is factored into the respective portion of dietary protein that humans derive from these various crops, it becomes clear that the overall amount of protein available for human consumption may drop by about 3 percent as atmospheric carbon dioxide reaches the levels anticipated to occur during the next few decades,” Bloom said.While heavy nitrogen fertilization could partially compensate for this decline in food quality, it would also have negative consequences including higher costs, more nitrate leaching into groundwater and increased emissions of the greenhouse gas nitrous oxide, he said.Story Source:The above story is based on materials provided by University of California – Davis. Note: Materials may be edited for content and length.

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Mortality risks of being overweight or obese are underestimated

New research by Andrew Stokes, a doctoral student in demography and sociology in the School of Arts and Sciences at the University of Pennsylvania, suggests that many obesity studies substantially underestimate the mortality risks associated with excess weight in the United States. His study, “Using Maximum Weight to Redefine Body Mass Index Categories in Studies of The Mortality Risks of Obesity,” was published in the March issue of the open-access journal Population Health Metrics.”The scholarly community is divided over a large meta-analysis that found that overweight is the optimal BMI category and that there are no increased risks associated with obese class 1,” Stokes said.Normal weight is indicated by a BMI of 18.5-24.9 kg/m2, overweight is indicated by a BMI of 25.0-29.9 kg/m2, obese class 1 is a BMI of 30.0-34.9 kg/m2 and obese class 2 is a BMI of 35.0 kg/m2 and above.Skeptics of the meta-analysis argue that the findings are likely driven by biases, especially by illness-induced weight loss.”Using BMI at the time of the survey to assess the mortality risks of overweight and obesity is problematic, especially in older populations, because slimness can be a marker of illness,” Stokes said.Researchers have attempted to address this bias by eliminating ill people from their samples; however, according to Stokes, such measures are inadequate because information on illness is ascertained by self-reporting and not everyone with an illness has been diagnosed.Stokes used individuals’ highest BMI in life to predict mortality rates. He said that in the previous literature, the normal weight category combines data from low-risk, stable-weight individuals with high-risk individuals who have experienced weight loss. Use of weight histories makes it possible to separate the two groups and redefine the reference category as people who were a consistently normal weight throughout their lives.Stokes conducted the analyses using data from the National Health and Nutrition Examination Surveys of 1988-1994 and 1999-2004 linked to the National Death Index through 2006 on U.S. adults ages 50-84 who never smoked.He found that the percentage of mortality attributable to overweight and obesity in this group was 33 percent when assessed using maximum BMI. The comparable figure obtained using BMI at the time of survey was substantially smaller at 5 percent.”The source of the discrepancy became clear when I started looking more closely at peoples’ weight histories,” Stokes said.Stokes said that a considerable fraction of individuals classified as normal weight using BMI at time of survey were formerly overweight or obese. This group had substantially elevated mortality rates compared to individuals that were consistently normal weight throughout their lives, suggesting that for many of them the weight loss was related to an illness.He concluded that the findings provide simple and compelling evidence that the prior literature underestimates the impact of obesity on levels of mortality in the U.S. But Stokes said that his results need corroboration in future studies because maximum BMI was calculated from peoples’ recollection of their maximum weight, which may be subject to recall error. He said that his analysis should be replicated using longitudinal data with contemporaneous measures of height and weight across the lifecycle.Story Source:The above story is based on materials provided by University of Pennsylvania. Note: Materials may be edited for content and length.

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Genes increase the stress of social disadvantage for some children

Genes amplify the stress of harsh environments for some children, and magnify the advantage of supportive environments for other children, according to a study that’s one of the first to document how genes interacting with social environments affect biomarkers of stress.”Our findings suggest that an individual’s genetic architecture moderates the magnitude of the response to external stimuli — but it is the environment that determines the direction” says Colter Mitchell, lead author of the paper and a researcher at the University of Michigan Institute for Social Research (ISR).The study, published today in the Proceedings of the National Academy of Sciences, uses telomere length as a marker of stress. Found at the ends of chromosomes, telomeres generally shorten with age, and when individuals are exposed to disease and chronic stress, including the stress of living in a disadvantaged environment.For the study, Mitchell and colleagues used telomere samples from a group of 40 nine-year-old boys from two very different environments – one nurturing and the other harsh. Those in the nurturing environment came from stable families, with nurturing parenting, good maternal mental health, and positive socioeconomic conditions, while those in the harsh environment experienced high levels of poverty, harsh parenting, poor maternal mental health, and high family instability.For those children with heightened sensitivity in the serotonergic and dopaminergic genetic pathways compared to other children, telomere length was shortest in a disadvantaged environment, and longest in a supportive environment.Story Source:The above story is based on materials provided by University of Michigan. Note: Materials may be edited for content and length.

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Unplanned pregnancy remains high among young Australian women

Despite high rates of contraceptive use, unwanted pregnancies resulting in terminations remain high among young women.In an article in the April issue of the Australian and New Zealand Journal of Public Health, Danielle Mazza from Monash University, and colleagues, examine the paradox of high rates of contraceptive use, over the counter availability of emergency contraception and unplanned pregnancy.”The emergency contraceptive pill has been available to women for over-the-counter purchase since 2004,” Professor Mazza said.”Together with high rates of contraceptive use, this should result in lower rates of unplanned pregnancies for Australian women, but it has not.”Although women have a high level of awareness of the emergency contraceptive pill, their knowledge about how and when to use it, and where to obtain it, remains inadequate.”Further research is needed to better understand the role of GPs in helping women to understand their contraceptive options and reduce unplanned pregnancy.”Story Source:The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length.

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Morning rays keep off pounds

A surprising new strategy for managing your weight? Bright morning light.A new Northwestern Medicine study reports the timing, intensity and duration of your light exposure during the day is linked to your weight — the first time this has been shown.People who had most of their daily exposure to even moderately bright light in the morning had a significantly lower body mass index (BMI) than those who had most of their light exposure later in the day, the study found. (BMI is a ratio calculated from a person’s weight and height.)”The earlier this light exposure occurred during the day, the lower individuals’ body mass index,” said co-lead author Kathryn Reid, research associate professor of neurology at Northwestern University Feinberg School of Medicine. “The later the hour of moderately bright light exposure, the higher a person’s BMI.”The influence of morning light exposure on body weight was independent of an individual’s physical activity level, caloric intake, sleep timing, age or season. It accounted for about 20 percent of a person’s BMI.”Light is the most potent agent to synchronize your internal body clock that regulates circadian rhythms, which in turn also regulate energy balance,” said study senior author Phyllis C. Zee, M.D. “The message is that you should get more bright light between 8 a.m. and noon.” About 20 to 30 minutes of morning light is enough to affect BMI.Zee is the Benjamin and Virginia T. Boshes Professor of Neurology and director of the Northwestern Medicine Sleep and Circadian Rhythms Research Program at Northwestern University Feinberg School of Medicine. She also is a neurologist at Northwestern Memorial Hospital.”If a person doesn’t get sufficient light at the appropriate time of day, it could de-synchronize your internal body clock, which is known to alter metabolism and can lead to weight gain,” Zee said. …

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Ancient nomads spread earliest domestic grains along Silk Road: Findings push back earliest known East-West interaction by 2,000 years

Charred grains of barley, millet and wheat deposited nearly 5,000 years ago at campsites in the high plains of Kazakhstan show that nomadic sheepherders played a surprisingly important role in the early spread of domesticated crops throughout a mountainous east-west corridor along the historic Silk Road, suggests new research from Washington University in St. Louis.”Our findings indicate that ancient nomadic pastoralists were key players in an east-west network that linked innovations and commodities between present-day China and southwest Asia,” said study co-author Michael Frachetti, PhD, an associate professor of archaeology in Arts & Sciences at Washington University and principal investigator on the research project.”Ancient wheat and broomcorn millet, recovered in nomadic campsites in Kazakhstan, show that prehistoric herders in Central Eurasia had incorporated both regional crops into their economy and rituals nearly 5,000 years ago, pushing back the chronology of interaction along the territory of the ‘Silk Road’ more than 2,000 years,” Frachetti said.The study, to be published April 2 in the Proceedings of the Royal Society B, establishes that several strains of ancient grains and peas had made their way across Eurasia thousands of years earlier than previously documented.While these crops have been known to exist much earlier in ancient China and Southwest Asia, finding them intermingled in the Bronze Age burials and households of nomadic pastoralists provides some of the earliest concrete signs for east-west interaction in the vast expanse of Eurasian mountains and the first botanical evidence for farming among Bronze Age nomads.Bread wheat, cultivated at least 6,000 years ago in Southwest Asia, was absent in China before 2500 B.C. while broomcorn millet, domesticated 8,000 years ago in China, is missing in southwest Asia before 2000 B.C. This study documents that ancient grains from eastern China and soutwest Asia had made their way to Kazakhstan in the center of the continent by 2700-2500 B.C. (nearly 5,000 years ago).”This study starts to rewrite the model for economic change across Eurasia,” said first author Robert Spengler, PhD, a paleoethnobotanist and research associate in Arts & Sciences at WUSTL.”It illustrates that nomads had diverse economic systems and were important for reshaping economic spheres more generally.”Findings are based on archaeobotanical data collected from four Bronze Age pastoralist campsites in Central Eurasian steppe/mountains: Tasbas and Begash in the highlands of Kazakhstan and Ojakly and Site 1211/1219 in Turkmenistan.”This is one of the first systematic applications of archaeobotany in the region, making the potential for further future discovery very exciting,” Spengler said.Frachetti and a team of WUSTL researchers led the on-site excavations, working closely with archaeologists based in Turkmenistan, Kazakhstan and Italy. Spengler conducted the paleoethnobotany laboratory work at WUSTL, under the directorship of Gayle J. Fritz, PhD, professor of archaeology and expert in human-plant relationships.”Finding this diverse crop assemblage at Tasbas and Begash illustrates first evidence for the westward spread of East Asian and Southwest Asian crops eastward, and the surprise is that it is nomads who are the agents of change,” Frachetti said.Story Source:The above story is based on materials provided by Washington University in St. Louis. The original article was written by Gerry Everding. Note: Materials may be edited for content and length.

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Monkey caloric restriction study shows big benefit; contradicts earlier study

The latest results from a 25-year study of diet and aging in monkeys shows a significant reduction in mortality and in age-associated diseases among those with calorie-restricted diets. The study, begun at the University of Wisconsin-Madison in 1989, is one of two ongoing, long-term U.S. efforts to examine the effects of a reduced-calorie diet on nonhuman primates.The study of 76 rhesus monkeys, reported Monday in Nature Communications, was performed at the Wisconsin National Primate Research Center in Madison. When they were 7 to 14 years of age, the monkeys began eating a diet reduced in calories by 30 percent. The comparison monkeys, which ate as much as they wanted, had an increased risk of disease 2.9 times that of the calorie-restricted group, and a threefold increased risk of death.”We think our study is important because it means the biology we have seen in lower organisms is germane to primates,” says Richard Weindruch, a professor of medicine at the School of Medicine and Public Health, and one of the founders of the UW study. “We continue to believe that mechanisms that combat aging in caloric restriction will offer a lead into drugs or other treatments to slow the onset of disease and death.”Restricting the intake of calories while continuing to supply essential nutrients extends the lifespan of flies, yeast and rodents by as much as 40 percent. Scientists have long wanted to understand the mechanisms for caloric restriction. “We study caloric restriction because it has such a robust effect on aging and the incidence and timing of age related disease,” says corresponding author Rozalyn Anderson, an assistant professor of geriatrics. “Already, people are studying drugs that affect the mechanisms that are active in caloric restriction. There is enormous private-sector interest in some of these drugs.”Still, the effects of caloric restriction on primates have been debated. …

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The science of champagne fizz: How many bubbles are in your bubbly?

The importance of fizz, more technically known as effervescence, in sparkling wines and champagnes is not to be underestimated — it contributes to the complete sensory experience of a glass, or flute, of fine bubbly. A scientist has now closely examined the factors that affect these bubbles, and he has come up with an estimate of just how many are in each glass. The report appears in ACS’ The Journal of Physical Chemistry B.Grard Liger-Belair notes that effervescence plays an important role in the look, taste, aroma and mouth feel of champagne and other sparkling wines. Wine journalists and bloggers often cite 15 million as the average number of bubbles fizzing in a single glass of champagne, based on some simple mathematics. Sounds impressive, but Liger-Belair suspected that the formula leading to this estimate oversimplified the matter. It didn’t take into account the fact that some of the dissolved carbon dioxide escapes from a glass without forming bubbles. Also, the size of the bubbles changes over time, and this could affect the final number. Liger-Belair wanted to set the record straight.Taking into consideration temperature, bubble dynamics and the tilt of a flute, Liger-Belair came up with a new way to calculate the number of bubbles in a glass of champagne. And the result is far lower than what has been cited. “One million bubbles seems to be a reasonable approximation for the whole number of bubbles likely to form if you resist drinking champagne from your flute,” he concludes. …

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Contrary to expectations, life experiences better use of money than material items

Despite knowing that buying life experiences will make them happier than buying material items, shoppers might continue to spend money on the latter because they mistakenly believe items are a better value, according to a San Francisco State University study published today. That belief, however, isn’t accurate.Those surveyed after making a purchase rated life experiences both making them happier and as a better use of their money, indicating many are sacrificing their well-being for a sense of value that never materializes. The study is one of the first to shed light on why people buy material items even though years of research has shown experiences provide a greater happiness boost.”People actually do know, and accurately predict, that life experiences will make them happier,” said SF State Associate Professor of Psychology Ryan Howell, a co-author of the study who has extensively researched the link between spending and happiness. “What they really underestimate is how much monetary value they will get out of a life experience. Even though they’re told experiences will make them happier and they know experiences will make them happier, they still perceive material items as being a better value.”Part of the reason, Howell suggests, is that material items are a tangible reminder of what the item is worth. Life experiences produce only memories, which can be harder to put a price tag on.”We naturally associate economic value with stuff. I bought this car, it’s worth $8,000,” he said. “We have a hard time estimating the economic value we would place on our memories.”To conduct the study, Howell and lead author Paulina Pchelin, a student at SF State when the research took place, surveyed individuals both before and after making a purchase. Prior to the purchase, respondents said they believed a life experience would make them happier but a material item would be a better use of their money. After the purchase, however, respondents reported that life experiences not only made them happier but were also the better value.”There were just huge underestimates in how much value people expected to get from their purchase,” Howell said. …

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Scientists solve the riddle of zebras’ stripes: Those pesky bugs

Why zebras have black and white stripes is a question that has intrigued scientists and spectators for centuries. A research team led by the University of California, Davis, has now examined this riddle systematically. Their answer is published April 1 in the online journal Nature Communications.The scientists found that biting flies, including horseflies and tsetse flies, are the evolutionary driver for zebra’s stripes. Experimental work had previously shown that such flies tend to avoid black-and-white striped surfaces, but many other hypotheses for zebra stripes have been proposed since Alfred Russel Wallace and Charles Darwin debated the problem 120 years ago.These include:A form of camouflage Disrupting predatory attack by visually confusing carnivores A mechanism of heat management Having a social function Avoiding ectoparasite attack, such as from biting flies The team mapped the geographic distributions of the seven different species of zebras, horses and asses, and of their subspecies, noting the thickness, locations, and intensity of their stripes on several parts of their bodies. Their next step was to compare these animals’ geographic ranges with different variables, including woodland areas, ranges of large predators, temperature, and the geographic distribution of glossinid (tsetse flies) and tabanid (horseflies) biting flies. They then examined where the striped animals and these variables overlapped.After analyzing the five hypotheses, the scientists ruled out all but one: avoiding blood-sucking flies.”I was amazed by our results,” said lead author Tim Caro, a UC Davis professor of wildlife biology. “Again and again, there was greater striping on areas of the body in those parts of the world where there was more annoyance from biting flies.”While the distribution of tsetse flies in Africa is well known, the researchers did not have maps of tabanids (horseflies, deer flies). Instead, they mapped locations of the best breeding conditions for tabanids, creating an environmental proxy for their distributions. They found that striping is highly associated with several consecutive months of ideal conditions for tabanid reproduction.Why would zebras evolve to have stripes whereas other hooved mammals did not? The study found that, unlike other African hooved mammals living in the same areas as zebras, zebra hair is shorter than the mouthpart length of biting flies, so zebras may be particularly susceptible to annoyance by biting flies.”No one knew why zebras have such striking coloration,” Caro said. …

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