Genome analysis helps in breeding more robust cows

Genome analysis of 234 bulls has put researchers, including several from Wageningen Livestock Research, on the trail of DNA variants which influence particular characteristics in breeding bulls. For example, two variants have proven responsible for disruptions to the development of embryos and for curly hair, which is disadvantageous because more ticks and parasites occur in curly hair than in short, straight hair. These are the first results of the large 1000 Bull Genomes project on which some 30 international researchers are collaborating. They report on their research in the most recent edition of the science journal Nature Genetics.Most breeding characteristics are influenced by not one but a multiplicity of variants. It is therefore important to be able to use all the variants in breeding, say the Wageningen researchers. In order to make this possible, Rianne van Binsbergen, PhD researcher at the Animal Breeding and Genomics Centre of Wageningen UR, investigated whether the genomes of all the common bulls in the Netherlands can be filled with the help of these 234 bulls. Currently, these bulls have been genotyped with markers of 50,000 or 700,000 DNA variants. The positive results indicate the direction for further research into the practical use of genome information in breeding.Dairy and beef cattle The project demonstrates how useful large-scale DNA analyses can be, says Professor Roel Veerkamp, Professor of Numerical Genetics at Wageningen University and board member of the 1000 Bull Genomes project. He emphasises that the requirements for dairy and beef cattle are becoming ever more exacting: “Until the mid nineties, a cow primarily had to produce a lot of milk. But since then, expectations have gone up. …

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Carbohydrate digestion and obesity strongly linked

New research indicates that obesity in the general population may be genetically linked to how our bodies digest carbohydrates.Published today in the journal Nature Genetics, the study investigated the relationship between body weight and a gene called AMY1, which is responsible for an enzyme present in our saliva known as salivary amylase. This enzyme is the first to be encountered by food when it enters the mouth, and it begins the process of starch digestion that then continues in the gut.People usually have two copies of each gene, but in some regions of our DNA there can be variability in the number of copies a person carries, which is known as copy number variation. The number of copies of AMY1 can be highly variable between people, and it is believed that higher numbers of copies of the salivary amylase gene have evolved in response to a shift towards diets containing more starch since prehistoric times.Researchers from Imperial College London, in collaboration with other international institutions, looked at the number of copies of the gene AMY1 present in the DNA of thousands of people from the UK, France, Sweden and Singapore. They found that people who carried a low number of copies of the salivary amylase gene were at greater risk of obesity.The chance of being obese for people with less than four copies of the AMY1 gene was approximately eight times higher than in those with more than nine copies of this gene. The researchers estimated that with every additional copy of the salivary amylase gene there was approximately a 20 per cent decrease in the odds of becoming obese.Professor Philippe Froguel, Chair in Genomic Medicine in the School of Public Health at Imperial College London, and one of the lead authors on the study, said: “I think this is an important discovery because it suggests that how we digest starch and how the end products from the digestion of complex carbohydrates behave in the gut could be important factors in the risk of obesity. Future research is needed to understand whether or not altering the digestion of starchy food might improve someone’s ability to lose weight, or prevent a person from becoming obese. We are also interested in whether there is a link between this genetic variation and people’s risk of other metabolic disorders such as diabetes, as people with a low number of copies of the salivary amylase gene may also be glucose intolerant.”Dr Mario Falchi, also from Imperial’s School of Public Health and first author of the study, said: “Previous genetic studies investigating obesity have tended to identify variations in genes that act in the brain and often result in differences in appetite, whereas our finding is related to how the body physically handles digestion of carbohydrates. We are now starting to develop a clearer picture of a combination of genetic factors affecting psychological and metabolic processes that contribute to people’s chances of becoming obese. This should ultimately help us to find better ways of tackling obesity.”Dr Julia El-Sayed Moustafa, another lead author from Imperial’s School of Public Health, said: “Previous studies have found rare genetic variations causing extreme forms of obesity, but because they occur in only a small number of people, they explained very little of the differences in body weight we see in the population. On the other hand, research on more common genetic variations that increase risk of obesity in the general population have so far generally found only a modest effect on obesity risk. …

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Pesticides make the life of earthworms miserable

Pesticides are sprayed on crops to help them grow, but the effect on earthworms living in the soil under the plants is devastating, new research reveals: The worms only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed.Pesticides have a direct impact on the physiology and behavior of earthworms, a Danish/French research team reports after having studied earthworms that were exposed to pesticides over generations.”We see that the worms have developed methods to detoxify themselves, so that they can live in soil sprayed with fungicide. They spend a lot of energy on detoxifying, and that comes with a cost: The worms do not reach the same size as other worms, and we see that there are fewer of them in sprayed soil. An explanation could be that they are less successful at reproducing, because they spend their energy on ridding themselves of the pesticide,” the researchers, Ph. D. student Nicolas Givaudan and associate professor, Claudia Wiegand, say.Claudia Wiegand is from the Department of Biology at University of Southern Denmark, and she led the research together with Francoise Binet from University Rennes 1 in France. Nicolas Givaudan is doing his Ph. D. as a joint degree between University of Southern Denmark and University of Rennes 1 in France. They researchers reached their findings by metabolomic profiling and energetic parameters.The researchers set up an experiment to study the behavior of the earthworm species Aporectodea caliginosa. They moved two portions of farmed soil with worms into the lab. …

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To pump or not to pump?

I’ve been pumping and donating since Ivy was 2 weeks old. Every night, I hook myself up to the pump, settle back into the couch, and pump a cup of liquid gold for my donor family. Sometimes I would be so tired when it came time to pump. I just want to go to bed…maybe I’ll do it in the morning…but still every night I would sit down, plug in, and pump.I love nursing my children, and I would be devastated if I were unable to breastfeed. That’s why I pump, even when I don’t feel like it.I’ve wondered how long I could continue pumping after I was done nursing my last baby…months? years? decades? Some wet nurses continued to nurse babies into …

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New insights into ancient Pacific settlers’ diet: Diet based on foraging, not horticulture

Researchers from New Zealand’s University of Otago studying 3000-year-old skeletons from the oldest known cemetery in the Pacific Islands are casting new light on the diet and lives of the enigmatic Lapita people, the likely ancestors of Polynesians.Their results — obtained from analysing stable isotope ratios of three elements in the bone collagen of 49 adults buried at the Teouma archaeological site on Vanuatu’s Efate Island — suggest that its early Lapita settlers ate reef fish, marine turtles, fruit bats, free-range pigs and chickens, rather than primarily relying on growing crops for human food and animal fodder.The findings are newly published in the journal PLOS ONE. Study lead author Dr Rebecca Kinaston and colleague Associate Professor Hallie Buckley at the Department of Anatomy carried out the research in collaboration with the Vanuatu National Museum and researchers from the University of Marseilles and CNRS (UMR 7269 and UMR 7041) in France and The Australian National University, Canberra.Dr Kinaston says the study is the most detailed analysis of Lapita diet ever undertaken and provides intriguing insights into the socio-cultural elements of their society.”It was a unique opportunity to assess the lifeways of a colonising population on a tropical Pacific island,” she says.The researchers analysed the isotopic ratios of carbon, nitrogen and sulphur in adult human bone collagen and compared these with ratios in ancient and modern plants and animals from the location, which provided a comprehensive dietary baseline.”Examining these ratios gave us direct evidence of the broad make-up of these adults’ diets over the 10-20 years before they died, which helps clear up the long-running debate about how the Lapita settlers sustained themselves during the early phases of colonising each island during their eastward drive across the Pacific.”Dr Kinaston says it appears that the new colonists, rather than relying mainly on a “transported landscape” of the crop plants and domesticated animals they brought with them, were practicing a mixed subsistence strategy.”The dietary pattern we found suggests that in addition to eating pigs and chickens, settlers were also foraging for a variety of marine food and consuming wild animals — especially fruit bats — and that whatever horticultural food they produced was not heavily relied on,” she says.Isotopic analysis of the ancient pig bones found at the site also suggests that they were free-ranging rather than penned and given fodder from harvested crops.Study of the human bones revealed a sex difference in diet compositions, showing that Lapita men had more varied diets and greater access to protein from sources such as tortoises, pigs and chicken than women did.”This may have resulted from unequal food distribution, suggesting that males may have been considered of higher status in Lapita society and treated preferentially,” Dr Kinaston says.Story Source:The above story is based on materials provided by University of Otago. Note: Materials may be edited for content and length.

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Almost 13 million smoking deaths could be prevented in China by 2050

China is home to about one third of the world’s smokers and reducing smoking in China could have an enormous public health impact, even on a global scale.Even though China raised the tax on tobacco products in 2009, this did not translate to higher retail prices for consumers and the only ban that has been enforced is on public transport. WHO went on to publish a report in 2011 which stated that there were multiple opportunities to improve tobacco control.Using a version of the SimSmoke Tobacco Control Policy model (a model of tobacco smoking prevalence and smoking-related deaths), populated with data from China, researchers from Spain, France and the US estimated the potential health impact of this programme in China from 2015 — 2050.Under current policies, a total of over 50 million deaths due to smoking were estimated from 2012 to 2050.Projecting the status quo scenario forward, the researchers estimate that active smoking in males would fall from 51.3% in 2015 to 46.5% by 2050 — and in females from 2.1% in 2015 to 1.3% in 2050In 2015, the estimated number of deaths from smoking was about one million (932,000 for males and 79,000 for females). In males, annual deaths were expected to peak at 1.5 million in 2040, but then drop to 1.4 million by 2050. In females, annual deaths from smoking were estimated to be 49,000 in 2040 and 42,000 by 2050.Relative to the status quo scenario, increasing cigarette taxes to 75% of the package price was estimated to reduce smoking prevalence by almost 10% for both males and females by 2015. By 2050, smoking prevalence showed a reduction of 13% for males and 12% for females. The researchers estimate that between 2015 and 2050, this tax would save approximately 3.5 million lives.Smoke-free air laws and a well enforced marketing ban also showed “potent and immediate” effects. Comprehensive smoke-free air laws were estimated to show a 9% reduction in smoking rates by 2015, increasing to about a 10% reduction in 2050, potentially averting around 3.4 million deaths. A comprehensive marketing ban would reduce smoking prevalence by about 4% and avert just over two million deaths by 2050.A high intensity tobacco control campaign would lead to a 2.5% relative decline in smoking rates by 2015 and prevent 1.1 million deaths due to smoking by 2050, while stronger health warnings were projected to yield a relative 2.3% reduction in smoking rates by 2050.The researchers estimate that complete implementation of the WHO framework “would lead to as much as a 34% relative reduction in male smoking prevalence by 2020, and a 41% reduction by 2050.” They say, despite the lag time expected between reductions in current smoking and declines in smoking attributable deaths, nearly half a million annual tobacco related deaths could be averted yearly by 2050.These estimates suggest that substantial health gains could be made, say the authors — a 40% relative reduction in smoking prevalence and almost 13 million smoking attributable deaths averted and more than 154 million life years gained by 2050 — by extending effective public health and clinical interventions to reduce active smoking. They add that these policies would be cost effective and say that “without the implementation of the complete set of stronger policies, the death and disability legacy of current smoking will endure for decades in China.”Story Source:The above story is based on materials provided by BMJ-British Medical Journal. Note: Materials may be edited for content and length.

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Threat of hidden crop pest to poorer nations revealed

The abundance of crop pests in developing countries may be greatly underestimated, posing a significant threat to some of the world’s most important food producing nations, according to research led by the University of Exeter.Data on the known distributions of almost 2,000 crop-destroying organisms in 195 countries were analyzed in the first global assessment of the factors determining the distribution of crop pests.Dr Dan Bebber and Professor Sarah Gurr, of Biosciences at the University of Exeter, found that if all countries had levels of scientific and technical capacity similar to the developed world, the number of pests reported would rise greatly and the true extent of the threat would be better understood.Many developing countries are expected to harbor hundreds of unreported crop pests and diseases, based on current levels of agricultural productivity.Around one sixth of the world’s agricultural production is lost to destructive organisms annually, with further losses post-harvest.Crop pests are often introduced by human activities such as trade and travel, with the wealth of a country linked to the number of invasive species recorded there because — whilst growing rich through trade — they have also accidentally imported pests in agricultural produce.But this study also considered the link between the wealth of a country (by per capita GDP) and its ability to detect, identify and report the number of crop pests present.Developing countries are less likely to have the capacity to observe invasive species than affluent, technologically-advanced nations.The researchers used data collated from published literature over many decades by the inter-governmental, not-for-profit organization CABI and made available from its Plantwise knowledge bank.Using GDP and scientific output as indicators of pest detection capacity, the study found that the pest load of the developing world appears to be greatly underestimated, and that this lack of knowledge may be severely hampering crop protection in some of the world’s most important food producing nations.Dr Dan Bebber said: “Crop pests pose a significant and growing threat to food security, but their geographical distributions are poorly understood.””Country wealth is likely to be a strong indicator of observational capacity, not just trade flow, as has been interpreted in previous studies of invasive species. If every country had US-levels of per capita GDP, then on average countries woul d be reporting more than 200 additional pests and diseases. This suggests that enhanced investment in pest observations will reveal the hidden threat of crop pests and pathogens, as well as bring into focus the opportunity to lose less of the crop by appropriate pest control. The first step to solving crop losses is to identify the pests responsible.”The largest numbers of crop pests were reported by the USA, followed by India, China, France and Japan. Island nations reported more pests than coastal and landlocked nations, and the number of pests increased slightly with rainfall.Professor Sarah Gurr added: “This follows hot on the heels of our recent paper showing that pests and pathogens are on the move in the face of climate change. When coupled to this study we can see that many nations are underestimating pest and pathogen loads. Taken collectively, these papers draw attention not only to the threat of crop disease, and thus global food security, but also to our need for more trained pathologists to inform policy.”Story Source:The above story is based on materials provided by University of Exeter. Note: Materials may be edited for content and length.

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Why do young people fail to find stable jobs and thrive?

Around the world, more and more young people are failing to find stable jobs and live independently. A new study from IIASA population researchers explains why.The numbers of young people who fail to transition from childhood to independent adulthood is growing — more and more young people find themselves without full-time jobs, relying on their parents, or staying longer in school. These changes can be traced changes in the global labor force and education according to a new study published today in the Finnish Yearbook of Population Research.”Young adults are doing increasingly worse economically, in spite of living in wealthy regions of the world,” says IIASA population expert Vegard Skirbekk. “At the same time, older adult age groups have been doing increasingly better.”Skirbekk, along with IIASA researchers Warren Sanderson and Marcin Stonawski conducted the study in order to examine the common factors that help young people transition to adulthood. They call the problem, “Young Adult Failure to Thrive Syndrome.”While the phenomenon had been recognized in individual countries, including Italy, France, Spain, and Japan, explanations have often focused on recent causes such as government fiscal difficulties. But the new study shows that failure to thrive can be traced to global economic and demographic shifts beginning in the 1980’s.The study finds that failure to thrive can be tied to three major economic factors worldwide. First, an increasingly globalized labor force means that workers can move more easily between countries. Second, education levels have soared around the world, meaning many more workers are available for skilled positions. Third, more women have joined the labor force. All these factors mean more competition for jobs, particularly for young people who have little practical experience.In addition to changes in labor supply, technological changes have both created and destroyed jobs, with a trend towards fewer industrial jobs and more service sector jobs.”These changes mean that even as economic conditions have improved for some in the population, young people are worse off today than they were 20 years ago,” says Sanderson.The researchers say that such economic disadvantages also have an effect on demographic questions such as fertility rates and family formation, as many young people cannot afford to start families until later in life.Story Source:The above story is based on materials provided by International Institute for Applied Systems Analysis. …

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Do you have a sweet tooth? Honeybees have a sweet claw

New research on the ability of honeybees to taste with claws on their forelegs reveals details on how this information is processed, according to a study published in the open-access journal, Frontiers in Behavioral Neuroscience.Insects taste through sensilla, hair-like structures on the body that contain receptor nerve cells, each of which is sensitive to a particular substance. In many insects, for example the honeybee, sensilla are found on the mouthparts, antenna and the tarsi — the end part of the legs. Honeybees weigh information from both front tarsi to decide whether to feed, finds the latest study led by Dr. Gabriela de Brito Sanchez, researcher, University of Toulouse, and Dr. Martin Giurfa, Director of the Research Centre on Animal Cognition, University of Toulouse, France.Hundreds of honeybees were included in the study. Sugary, bitter and salty solutions were applied to the tarsi of the forelegs to test if this stimulated the bees to extend or retract their tongue — reflex actions that indicate whether or not they like the taste and are preparing to drink. Results revealed that honeybee tarsi are highly sensitive to sugar: even dilute sucrose solutions prompted the bees to extend their tongue. Measurements of nerve cell activity showed that the part of the honeybee tarsus most sensitive to sugary tastes is the double claw at its end. Also, the segments of the tarsus before the claws, known as the tarsomeres, were found to be highly sensitive to saline solutions.”Honeybees rely on their color vision, memory, and sense of smell and taste to find nectar and pollen in the ever-changing environment around the colony,” says Dr. Giurfa. …

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Hot weather deaths projected to rise 257 percent in UK by 2050s, experts warn

The number of annual excess deaths caused by hot weather in England and Wales is projected to surge by 257% by the middle of the century, as a result of climate change and population growth, concludes research published online in the Journal of Epidemiology and Community Health.The elderly (75+) will be most at risk, particularly in the South and the Midlands, the findings suggest.The research team, from the London School of Hygiene and Tropical Medicine, and Public Health England, used time-series regression analysis to chart historic (1993-2006) fluctuations in weather patterns and death rates to characterise the associations between temperature and mortality, by region and by age group.They then applied these to projected population increases and local climate to estimate the future number of deaths likely to be caused by temperature — hot and cold — for the 2020s, 2050s, and 2080s.They based their calculations on the projected daily average temperatures for 2000-09, 2020-29, 2050-59 and 2080-89, derived from the British Atmospheric Data Centre (BADC), and population growth estimates from the Office of National Statistics.The calculations indicated a significantly increased risk of deaths associated with temperature across all regions of the UK, with the elderly most at risk.The number of hot weather days is projected to rise steeply, tripling in frequency by the mid 2080s, while the number of cold days is expected to fall, but at a less dramatic pace.At the national level, the death rate increases by just over 2% for every 1ᵒC rise in temperature above the heat threshold, with a corresponding 2% increase in the death rate for every 1ᵒC fall in temperature below the cold threshold.In the absence of any adaptive measures, excess deaths related to heat would be expected to rise by 257% by the 2050s, from an annual baseline of 2000, while those related to the cold would be expected to fall by 2% as a result of milder winters, from a current toll of around 41,000, but will still remain significant.Those aged 85 and over will be most at risk, partly as a result of population growth — projected to reach 89 million by the mid 2080s — and the increasing proportion of elderly in the population, say the authors.Regional variations are likely to persist: London and the Midlands are the regions most vulnerable to the impact of heat, while Wales, the North West, Eastern England and the South are most vulnerable to the impact of cold.Rising fuel costs may make it harder to adapt to extremes of temperature, while increased reliance on active cooling systems could simply end up driving up energy consumption and worsening the impact of climate change, say the authors.Better and more sustainable options might instead include shading, thermal insulation, choice of construction materials implemented at the design stage of urban developments, suggest the authors.While the death toll from cold weather temperatures will remain higher than that caused by hot temperatures, the authors warn that health protection from hot weather will become increasingly necessary — and vital for the very old.”As the contribution of population growth and aging on future temperature related health burdens will be large, the health protection of the elderly will be important,” warn the authors, recalling the social changes that have led to many elderly living on their own — a contributory factor to the high death toll in France in the 2003 heatwave.

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How Earth’s rotation affects vortices in nature, such as hurricanes and ocean currents

Oct. 15, 2013 — What do smoke rings, tornadoes and the Great Red Spot of Jupiter have in common? They are all examples of vortices, regions within a fluid (liquid, gas or plasma) where the flow spins around an imaginary straight or curved axis. Understanding how geophysical (natural world) vortices behave can be critical for tasks such as weather forecasting and environmental pollution monitoring.In a new paper in the journal Physics of Fluids, researchers Junho Park and Paul Billant of the CNRS Laboratoire d’Hydrodynamique in France describe their study of one such geophysical vortex behavior, radiative instability, and how it is affected by two factors, density stratification and background rotation.Radiative instability is a phenomenon that alters the behavior of fluid flows and can deform a vortex. The “radiative” tag refers to the fact that it is an instability caused by the radiation of waves outward from a vortex.”These waves can exist as soon as there is a density stratification — a variation of densities — throughout the vertical column of the vortex,” Park said. “In this study, we have considered how background rotation — in this case, the rotation of the Earth — impacts them.”Examples of density stratification in nature, Park explained, include the decrease in air density as one moves higher in the atmosphere or the increase in water density due to salinity and temperature with increasing ocean depth. “So, the waves in our mathematical model are somewhat analogous to waves on the ocean surface,” he said. “Likewise, the impact from background rotation on our modeled waves serves as an equal for the impact of the Coriolis force caused by the Earth’s rotation.””What we learned from our models is that strong background rotation suppresses the radiative instability, a characteristic that had been expected but whose dynamics had never been studied precisely,” Park said. “We’ve now developed a sophisticated mathematical means to explain this phenomenon, and that’s important to being better able to study and understand the behavior of geophysical vortices such as hurricanes and ocean currents.”Park said that he and Billant next plan to study instability behaviors in vortices with non-columnar shapes. “For example,” he said, “there are pancake-shaped flows called Mediterranean eddies, or meddies, that would be worth studying since we know they affect the mixing of the components that make up the ocean ecosystem.”

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Two forms of Parkinson’s disease identified

Oct. 11, 2013 — Why can the symptoms of Parkinson’s disease vary so greatly from one patient to another? A consortium of researchers, headed by a team from the Laboratoire CNRS d’Enzymologie et Biochimie Structurales, is well on the way to providing an explanation. Parkinson’s disease is caused by a protein known as alpha-synuclein, which forms aggregates within neurons, killing them eventually. The researchers have succeeded in characterizing and producing two different types of alpha-synuclein aggregates. Better still, they have shown that one of these two forms is much more toxic than the other and has a greater capacity to invade neurons. This discovery takes account, at the molecular scale, of the existence of alpha-synuclein accumulation profiles that differ from one patient to the next. These results, published on October 10 in Nature Communications, represent a notable advance in our understanding of Parkinson’s disease and pave the way for the development of specific therapies targeting each form of the disease.Parkinson’s disease, which is the second most frequent neurodegenerative disease after Alzheimer’s, affects some 150,000 people in France. According to those suffering from the disease, it can manifest itself in the form of uncontrollable shaking (in 60% of patients) or by less-localized symptoms such as depression, behavioral and motor disorders. These differences in symptoms point to different forms of Parkinson’s disease.This condition, for which no curative treatment currently exists, is caused by the aggregation in the form of fibrillar deposits of alpha-synuclein, a protein that is naturally abundant at neuron junctions. …

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Hottest days in some parts of Europe have warmed four times more than the global average

Sep. 11, 2013 — Some of the hottest days and coldest nights in parts of Europe have warmed more than four times the global average change since 1950, according to a new paper by researchers from the Grantham Research Institute on Climate Change and the Environment at the London School of Economics and Political Science and the University of Warwick, which is published today (11 September 2013) in the journal Environmental Research Letters.The researchers translated observations of weather into observations of climate change using a gridded dataset of observations stretching back to 1950. The hottest 5 per cent of days in summer have warmed fastest in a band from southern England and northern France to Denmark. By contrast, the average and slightly hotter than average days have warmed most in regions further south in France and Germany. In eastern Spain and central Italy there has been broad warming across all types of days, but in most places those days which are cooler than average have not warmed so much.The paper points out that some locations and temperature thresholds have seen little change since 1950. The authors suggest that the results highlight the scale of the difference between global change and the local climate changes felt by individuals.Dr. David Stainforth, the lead author on the paper, said: “Climate is fundamentally the distributions of weather. As climate changes, the distributions change. But they don’t just shift, they change shape. How they change shape depends on where you are. …

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Argan powder found in some cosmetics linked with occupational asthma

Sep. 9, 2013 — Argan powder, which is used by the cosmetic industry in the production of foundation products, could be linked with occupational asthma.Share This:A small study, presented at the European Respiratory Society (ERS) Annual Congress in Barcelona on 9 September 2013, has found the first evidence of a risk associated with the use of argan powder during the industrial production of cosmetics.A sample of nine patients from a cosmetic factory in France were analysed in the study. All participants were exposed to the product in three different forms: crude granules, powder or liquid.Each participant completed a questionnaire about their medical history. Lung function tests and allergy tests were also carried out, along with an inhalation challenge test, which examines the airways specific reaction to a substance (in this case argan).Out of the nine workers, four displayed asthma or rhinitis symptoms and had a blocked nose when handling argan powder. The results found that three of them had occupational asthma caused by argan powder, proved by specific challenge tests. Two of the four also had a positive allergy skin prick-test to argan powder.Dr Emmanuelle Penven, lead author of the study, said: “Occupational asthma can be a debilitating condition if it prevents a person from working. This study is very preliminary but does suggest an association between argan powder and occupational asthma. Our initial findings warrant further research to understand any health risks associated with the compound.”Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by European Lung Foundation, via AlphaGalileo. Note: Materials may be edited for content and length. For further information, please contact the source cited above. …

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Frogs that hear with their mouth: X-rays reveal a new hearing mechanism for animals without an ear

Sep. 2, 2013 — Gardiner’s frogs from the Seychelles islands, one of the smallest frogs in the world, do not possess a middle ear with an eardrum yet can croak themselves, and hear other frogs. An international team of scientists using X-rays has now solved this mystery and established that these frogs are using their mouth cavity and tissue to transmit sound to their inner ears.The results are published in the Proceedings of the National Academy of Sciences on September 2, 2013.The team led by Renaud Boistel from CNRS and University of Poitiers, comprised also scientists from Institut Langevin of ESPCI ParisTech, the Laboratoire de Mécanique et d’Acoustique in Marseilles, the Institute of Systems and Synthetic Biology at the University of Evry (France), the Nature Protection Trust of Seychelles, and the European Synchrotron ESRF in Grenoble.The way sound is heard is common to many lineages of animals and appeared during the Triassic age (200-250 million years ago). Although the auditory systems of the four-legged animals have undergone many changes since, they have in common the middle ear with eardrum and ossicles, which emerged independently in the major lineages. On the other hand, some animals notably most frogs, do not possess an outer ear like humans, but a middle ear with an eardrum located directly on the surface of the head. Incoming sound waves make the eardrum vibrate, and the eardrum delivers these vibrations using the ossicles to the inner ear where hair cells translate them into electric signals sent to the brain. Is it possible to detect sound in the brain without a middle ear? The answer is no because 99.9% of a sound wave reaching an animal is reflected at the surface of its skin.”However, we know of frog species that croak like other frogs but do no have tympanic middle ears to listen to each other. This seems to be a contradiction,” says Renaud Boistel from the IPHEP of the University of Poitiers and CNRS. “These small animals, Gardiner’s frogs, have been living isolated in the rainforest of the Seychelles for 47 to 65 million years, since these islands split away from the main continent. …

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‘Trojan’ asteroids in far reaches of solar system more common than previously thought

Aug. 29, 2013 — UBC astronomers have discovered the first Trojan asteroid sharing the orbit of Uranus, and believe 2011 QF99 is part of a larger-than-expected population of transient objects temporarily trapped by the gravitational pull of the Solar System’s giant planets.Trojans are asteroids that share the orbit of a planet, occupying stable positions known as Lagrangian points. Astronomers considered their presence at Uranus unlikely because the gravitational pull of larger neighbouring planets would destabilize and expel any Uranian Trojans over the age of the Solar System.To determine how the 60 kilometre-wide ball of rock and ice ended up sharing an orbit with Uranus the astronomers created a simulation of the Solar System and its co-orbital objects, including Trojans.”Surprisingly, our model predicts that at any given time three per cent of scattered objects between Jupiter and Neptune should be co-orbitals of Uranus or Neptune,” says Mike Alexandersen, lead author of the study to be published tomorrow in the journal Science. This percentage had never before been computed, and is much higher than previous estimates.Several temporary Trojans and co-orbitals have been discovered in the Solar System during the past decade. QF99 is one of those temporary objects, only recently (within the last few hundred thousand years) ensnared by Uranus and set to escape the planet’s gravitational pull in about a million years.”This tells us something about the current evolution of the Solar System,” says Alexandersen. “By studying the process by which Trojans become temporarily captured, one can better understand how objects migrate into the planetary region of the Solar System.”UBC astronomers Brett Gladman, Sarah Greenstreet and colleagues at the National Research Council of Canada and Observatoire de Besancon in France were part of the research team.

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Handaxe design reveals distinct Neanderthal cultures

Aug. 19, 2013 — A study by a postgraduate researcher at the University of Southampton has found that Neanderthals were more culturally complex than previously acknowledged. Two cultural traditions existed among Neanderthals living in what is now northern Europe between 115,000 to 35,000 years ago.Dr Karen Ruebens from the Centre for the Archaeology of Human Origins (CAHO) and funded by the Arts and Humanities Research Council (AHRC) examined the design of 1,300 stone tools originating from 80 Neanderthal sites in five European countries; France, Germany, Belgium, Britain and the Netherlands.Dr Ruebens’ investigations uncovered new evidence that two separate handaxe traditions or designs existed — one in a region now spanning south-western France and Britain — the other in Germany and further to the East. In addition, she found an area covering modern day Belgium and the Netherlands that demonstrates a transition between the two.She comments: “In Germany and France there appears to be two separate handaxe traditions, with clear boundaries, indicating completely separate, independent developments. “The transition zone in Belgium and Northern France indicates contact between the different groups of Neanderthals, which is generally difficult to identify but has been much talked about, especially in relation to later contacts with groups of modern humans. This area can be seen as a melting pot of ideas where mobile groups of Neanderthals, both from the eastern and western tradition, would pass by — influencing each other’s designs and leaving behind a more varied record of bifacial tools.”The University of Southampton research has revealed Neanderthals in the western region made symmetrical, triangular and heart-shaped handaxes, while during the same time period, in the eastern region, they produced asymmetrically shaped bifacial knives.Dr Ruebens says: “Distinct ways of making a handaxe were passed on from generation to generation and for long enough to become visible in the archaeological record. This indicates a strong mechanism of social learning within these two groups and says something about the stability and connectivity of the Neanderthal populations.”Making stone tools was not merely an opportunistic task. A lot of time, effort and tradition were invested and these tools carry a certain amount of socio-cultural information, which does not contribute directly to their function.”The study’s extensive analysis also shows other factors which could have influenced handaxe design, such as raw material availability to Neanderthals, the function of their sites, or the repeated reuse and sharpening of tools — didn’t have an impact in this instance.

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Early surgery better than watchful waiting for patients with severe mitral valve regurgitation

Aug. 13, 2013 — Patients with severe mitral valve regurgitation who are otherwise healthy should have mitral valve repair surgery sooner rather than later, even if they feel no symptoms, a Mayo Clinic-led study by U.S. and European researchers found. The results challenge the long-held belief that it is safer to “watch and wait” until a patient has symptoms, such as shortness of breath. This is the largest study to show that patients who undergo surgery early after diagnosis have improved long-term survival and lower risk of heart failure.The findings will be published Tuesday in the Journal of the American Medical Association.Mitral valve regurgitation is common and increasing in frequency; it is estimated that by 2030, close to 5 million Americans will have moderate to severe mitral valve regurgitation. It occurs when the mitral valve does not close properly, causing blood to be pumped backward instead of forward. Oxygen-rich blood is thus unable to move through the heart to the rest of the body as efficiently. A heart murmur is often the first sign of mitral valve prolapse. As mitral valve disease progresses, symptoms may be absent due to the body’s ability to compensate. This initial lack of symptoms preserves quality of life, but prevents patients from being alerted to the seriousness of their condition. …

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Light slowed to a crawl in liquid crystal matrix

Aug. 13, 2013 — Light traveling in a vacuum is the Universe’s ultimate speed demon, racing along at approximately 300,000 kilometers per second. Now scientists have found an effective new way to put a speed bump in light’s path. Reported today in The Optical Society’s (OSA) open-access journal Optics Express, researchers from France and China embedded dye molecules in a liquid crystal matrix to throttle the group velocity of light back to less than one billionth of its top speed. The team says the ability to slow light in this manner may one day lead to new technologies in remote sensing and measurement science.The new approach to manipulating light, conducted by a group from France’s Université de Nice-Sophia Antipolis and China’s Xiamen University, uses little power, does not require an external electrical field, and operates at room temperature, making it more practical than many other slow light experiments. Putting the brakes on light can help scientists compare the characteristics of different light pulses more easily, which in turn can help them build highly sensitive instruments to measure extremely slow speeds and small movements, says Umberto Bortolozzo, one of the authors on the Optics Express paper. In a second paper, also published today and appearing in OSA’s journal Optics Letters, Bortolozzo and colleagues from the Université de Nice-Sophia Antipolis and the University of Rochester describe an instrument that uses slow light to measure speeds less than one trillionth of a meter per second.Scientists have known for a long time that a wave packet of light becomes more sluggish when it travels through matter, but the magnitude of this slow-down in typical materials such as glass or water is less than a factor of two. “The question is: can we do something to the matter in order to make light slow down much more considerably?” says Bortolozzo.The key to achieving a significant drop-off in speed is to take advantage of the fact that when light travels as a pulse it is really a collection of waves, each having a slightly different frequency, says Bortolozzo. However, all the waves in the pulse must travel together. Scientists can design materials to be like obstacles courses that “trip up” some of the waves more than others. …

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Neuroscientists identify protein linked to Alzheimer’s-like afflictions

Aug. 11, 2013 — A team of neuroscientists has identified a modification to a protein in laboratory mice linked to conditions associated with Alzheimer’s Disease. Their findings, which appear in the journal Nature Neuroscience, also point to a potential therapeutic intervention for alleviating memory-related disorders.The research centered on eukaryotic initiation factor 2 alpha (eIF2alpha) and two enzymes that modify it with a phosphate group; this type of modification is termed phosphorylation. The phosphorylation of eIF2alpha, which decreases protein synthesis, was previously found at elevated levels in both humans diagnosed with Alzheimer’s and in Alzheimer’s Disease (AD) model mice.”These results implicate the improper regulation of this protein in Alzheimer’s-like afflictions and offer new guidance in developing remedies to address the disease,” said Eric Klann, a professor in New York University’s Center for Neural Science and the study’s senior author.The study’s co-authors also included: Douglas Cavener, a professor of biology at Pennsylvania State University; Clarisse Bourbon, Evelina Gatti, and Philippe Pierre of Université de la Méditerranée in Marseille, France; and NYU researchers Tao Ma, Mimi A. Trinh, and Alyse J. Wexler.It has been known for decades that triggering new protein synthesis is vital to the formation of long-term memories as well as for long-lasting synaptic plasticity — the ability of the neurons to change the collective strength of their connections with other neurons. Learning and memory are widely believed to result from changes in synaptic strength.In recent years, researchers have found that both humans with Alzheimer’s Disease and AD model mice have relatively high levels of eIF2alpha phosphorylation. But the relationship between this characteristic and AD-related afflictions was unknown.Klann and his colleagues hypothesized that abnormally high levels of eIF2alpha phosphorylation could become detrimental because, ultimately, protein synthesis would diminish, thereby undermining the ability to form long-term memories.To explore this question, the researchers examined the neurological impact of two enzymes that phosphorylate eIF2alpha, kinases termed PERK and GCN2, in different populations of AD model mice — all of which expressed genetic mutations akin to those carried by humans with AD. These were: AD model mice; AD model mice that lacked PERK; and AD model mice that lacked GCN2.Specifically, they looked at eIF2alpha phosphorylation and the regulation of protein synthesis in the mice’s hippocampus region — the part of the brain responsible for the retrieval of old memories and the encoding of new ones. They then compared these levels with those of postmortem human AD patients.Here, they found both increased levels of phosphorylated eIF2alpha in the hippocampus of both AD patients and the AD model mice. …

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