Tsetse fly genome reveals weaknesses: International 10-year project unravels biology of disease-causing fly

Mining the genome of the disease-transmitting tsetse fly, researchers have revealed the genetic adaptions that allow it to have such unique biology and transmit disease to both humans and animals.The tsetse fly spreads the parasitic diseases human African trypanosomiasis, known as sleeping sickness, and Nagana that infect humans and animals respectively. Throughout sub-Saharan Africa, 70 million people are currently at risk of deadly infection. Human African trypanosomiasis is on the World Health Organization’s (WHO) list of neglected tropical diseases and since 2013 has become a target for eradication. Understanding the tsetse fly and interfering with its ability to transmit the disease is an essential arm of the campaign.This disease-spreading fly has developed unique and unusual biological methods to source and infect its prey. Its advanced sensory system allows different tsetse fly species to track down potential hosts either through smell or by sight. This study lays out a list of parts responsible for the key processes and opens new doors to design prevention strategies to reduce the number of deaths and illness associated with human African trypanosomiasis and other diseases spread by the tsetse fly.”Tsetse flies carry a potentially deadly disease and impose an enormous economic burden on countries that can least afford it by forcing farmers to rear less productive but more trypanosome-resistant cattle.” says Dr Matthew Berriman, co-senior author from the Wellcome Trust Sanger Institute. “Our study will accelerate research aimed at exploiting the unusual biology of the tsetse fly. The more we understand, the better able we are to identify weaknesses, and use them to control the tsetse fly in regions where human African trypanosomiasis is endemic.”The team, composed of 146 scientists from 78 research institutes across 18 countries, analysed the genome of the tsetse fly and its 12,000 genes that control protein activity. The project, which has taken 10 years to complete, will provide the tsetse research community with a free-to-access resource that will accelerate the development of improved tsetse-control strategies in this neglected area of research.The tsetse fly is related to the fruit fly — a favoured subject of biologists for more than 100 years — but its genome is twice as large. Within the genome are genes responsible for its unusual biology. …

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

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

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Number of babies mom has may play role in future cardiovascular health

Women who give birth to four or more children are much more likely to have evidence of plaque in their heart or thickening of their arteries — early signs of cardiovascular disease — compared with those having fewer pregnancies, according to research to be presented at the American College of Cardiology’s 63rd Annual Scientific Session.While earlier studies have shown an association between several aspects of pregnancy — physiological changes, complications, number of pregnancies — and future heart disease risk, many questions remain about how pregnancy might affect cardiovascular risk. To better understand the potential link, researchers at the University of Texas Southwestern Medical Center set out to determine whether the number of live births is associated with early signs of cardiovascular disease.”This is not a recommendation for women to only have two or three children,” said Monika Sanghavi, M.D., chief cardiology fellow, University of Texas Southwestern Medical Center, and lead investigator of the study. This is the first study to look at two markers of subclinical atherosclerosis — a gradual narrowing and hardening of the arteries that can eventually block blood flow and lead to stroke and heart attack.”Our findings add to the growing body of evidence that the changes associated with pregnancy may provide insight into a woman’s future cardiovascular risk and deserves further attention.”The study included 1,644 women from the Dallas Heart Study, a multiethnic population-based cohort, who had both self-reported information about the number of live births and relevant imaging study data available. The average age at the time of analysis was 45 years and slightly more than half of the women (55 percent) were African-American. Coronary artery calcium (CAC) scores were measured using computed tomography imaging and aortic wall thickness (AWT) by magnetic resonance imaging to determine whether or not women had evidence of subclinical atherosclerosis in the heart and artery walls. CAC was positive if it was greater than 10 and AWT was abnormal if it was greater than the 75th percentile for age and gender. These tests were done as part of standard subject participation in the Dallas Heart Study.Using women who had two or three live births as a reference, women who had given birth to four or more children had an approximately two-fold increased risk of having abnormal CAC or AWT. This association remained even after adjusting for socioeconomic status, education, race and factors known to heighten the risk of cardiovascular disease. Women who had more babies were more likely to be older, Hispanic, have high blood pressure, higher body mass index and lower socioeconomic status.Curiously, women who had zero or just one live birth were also more likely to show evidence of subclinical atherosclerosis — revealing a U-shaped relationship.Authors say it is unclear why this might be the case. But Sanghavi and others speculate they may have captured some women in this group who have an underlying condition that prevents them from carrying a first or second pregnancy to term, which may also predispose them to cardiovascular disease or risk factors. …

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The parasite that escaped out of Africa: Tracing origins of malaria parasite

An international team of scientists has traced the origin of Plasmodium vivax, the second-worst malaria parasite of humans, to Africa, according to a study published this week in Nature Communications. Until recently, the closest genetic relatives of human P. vivax were found only in Asian macaques, leading researchers to believe that P. vivax originated in Asia.The study, led by researchers from the Perelman School of Medicine at the University of Pennsylvania, found that wild-living apes in central Africa are widely infected with parasites that, genetically, are nearly identical to human P. vivax.This finding overturns the dogma that P. vivax originated in Asia, despite being most prevalent in humans there now, and also solves other vexing questions about P. vivax infection: how a mutation conferring resistance to P. vivax occurs at high frequency in the very region where this parasite seems absent and how travelers returning from regions where almost all humans lack the receptor for P. vivax can be infected with this parasite.Of Ape and Human ParasitesMembers of the labs of Beatrice Hahn, MD, and George Shaw, MD, PhD, both professors of Medicine and Microbiology at Penn, in collaboration with Paul Sharp, PhD, an evolutionary biologist from the University of Edinburgh, and Martine Peeters, PhD, a microbiologist from the Institut de Recherche pour le Dveloppement and the University of Montpellier, tested over 5,000 ape fecal samples from dozens of field stations and sanctuaries in Africa for P. vivax DNA. …

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Asian elephants reassure others in distress: First empirical evidence of consolation in elephants

Asian elephants console others who are in distress, using physical touches and vocalizations, finds a study to be published in the open access journal PeerJ. The findings are the first empirical evidence of consolation in elephants, says lead author Joshua Plotnik, who began the research as a graduate student of psychology at Emory University.”For centuries, people have observed that elephants seem to be highly intelligent and empathic animals, but as scientists we need to actually test it,” he says.Consolation behavior is rare in the animal kingdom, with empirical evidence previously provided only for the great apes, canines and certain corvids.”With their strong social bonds, it’s not surprising that elephants show concern for others,” says co-author Frans de Waal, an Emory professor of psychology and director of Living Links at Emory’s Yerkes National Primate Research Center. “This study demonstrates that elephants get distressed when they see others in distress, reaching out to calm them down, not unlike the way chimpanzees or humans embrace someone who is upset.”Plotnik received his Ph.D. from Emory in 2010 and is currently a lecturer in conservation biology at Mahidol University in Thailand and CEO of Think Elephants International, a non-profit focused on education and conservation. His main research interest is convergent cognitive evolution: The independent evolution of similar features of intelligence in species of different lineages.While Plotnik was still at Emory, he and de Waal provided evidence that elephants can both recognize themselves in a mirror — a test of self-awareness passed only by some apes, dolphins and magpies — and problem-solve cooperatively.”Humans are unique in many ways, but not in as many ways as we once thought,” Plotnik says.The current study focused on a group of 26 captive Asian elephants spread over about 30 acres at an elephant camp in northern Thailand. For nearly a year, the researchers observed and recorded incidents when an elephant displayed a stress reaction, and the responses from other nearby elephants.The initial stress responses came from either unobservable, or obvious, stimuli: Events such as a dog walking past, a snake or other potentially dangerous animal rustling the grass, or the presence of another, unfriendly elephant. “When an elephant gets spooked, its ears go out, its tail stands erect or curls out, and it may emit a low-frequency rumble, trumpet and roar to signal its distress,” Plotnik says.The study found that nearby elephants affiliated significantly more with a distressed individual through directed, physical contact following a stress event than during control periods. As a typical example, a nearby elephant would go to the side of the distressed animal and use its trunk to gently touch its face, or put its trunk in the other animal’s mouth.The gesture of putting their trunks in each other’s mouths is almost like an elephant handshake or hug, Plotnik says. “It’s a very vulnerable position to put yourself in, because you could get bitten. It may be sending a signal of, ‘I’m here to help you, not hurt you.'”The responding elephants also showed a tendency to vocalize. …

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Massachusetts’ fire-safe cigarette law appears to decrease likelihood of residential fires

A six-year-old Massachusetts law requiring that only “fire-safe” cigarettes (FSCs) be sold in the state appears to decrease the likelihood of unintentional residential fires caused by cigarettes by 28%, according to a new study by Harvard School of Public Health (HSPH) researchers.The study will appear online February 13, 2014 in the American Journal of Public Health.”This study is the first rigorous population-based study to evaluate the effectiveness of the fire-safe cigarette standards, and shows that science-based tobacco product regulation can protect the public health,” said lead author Hillel Alpert, research scientist at the Center for Global Tobacco Control at HSPH.Burning cigarettes left smoldering on a bed, furniture, or other flammable material are a leading cause of residential fires in the United States, generating hundreds of millions of dollars each year in property damage, health care costs, lost productivity, death, and injuries. Young children, seniors, African Americans, Native Americans, the poor, people living in rural areas or in substandard housing, and firefighters are especially at risk.To evaluate the effectiveness of Massachusetts’ Fire Safe Cigarette Law, the researchers analyzed seven years of data from 2004 to 2010 on accidental residential fires, including 1,629 caused by cigarettes. The information was reported to the Massachusetts Fire Incident Reporting System, a system maintained by the Massachusetts Department of Fire Services.The results appear to show that the likelihood of unintentional residential fires caused by cigarettes decreased by 28% after the Massachusetts law was enacted in 2008. The largest reductions were among cigarette fires in which human factors, such as falling asleep while smoking, were involved, and among fires that were ignited on materials, which are the scenarios for which the standard was developed.”This study confirms that the fire standard compliant (FSC) cigarette law has reduced the number of fires from cigarettes started by igniting furniture and bedding as it was designed to do,” said Massachusetts Fire Marshal Stephen Coan.”We now have the science to support that all tobacco companies throughout the world should voluntarily make their cigarettes less likely to ignite fires,” said Gregory Connolly, professor of the practice of public health and director of the HSPH Center for Global Tobacco Control.Story Source:The above story is based on materials provided by Harvard School of Public Health. Note: Materials may be edited for content and length.

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South African healthcare workers face greater risk for TB, HIV

A large-scale survey of South African healthcare workers has revealed major gaps in workplace protection against tuberculosis, HIV and hepatitis, according to a University of British Columbia health researcher.Presenting findings today at the 2014 annual meeting of the American Association for the Advancement of Science (AAAS), Dr. Annalee Yassi says issues such as confidentiality, stigma, technological capacity and staff training need to be addressed while improving hospital resources and protocols.Preliminary results of the 2012 baseline survey of more than 1,000 healthcare workers in three hospitals show that more than 68 per cent of patient care staff had never been screened for TB; nearly 20 per cent were not vaccinated against hepatitis; and 55 per cent did not wear respiratory protection when needed. Despite South Africa’s high TB and HIV rates — 18 per cent of its adult population is HIV-positive — and risk of hepatitis transmission, recapping of used needles before disposal and washing and reusing of gloves were common, with more than 20 per cent surveyed reporting needlestick injury or unprotected exposure to bodily fluids.Yassi, who is helping South Africa implement occupational health guidelines developed by the World Health Organization (WHO), says healthcare workers in developing countries face greater health challenges while serving significantly more patients.”In addition to massive workloads, healthcare workers in developing countries are more likely to get sick from the workplace,” says Yassi, a professor in UBC’s School of Population and Public Health, noting that healthcare workers in South Africa are at three times the risk of contracting TB than other South Africans, and more than seven times more likely to be hospitalized for drug-resistant TB. A 2013 WHO estimate showed South Africans were almost 300 times more likely to contract TB than Americans.”Considerable progress is being made, including better standard operating procedures and screening,” says Yassi. “But there’s much more we can do to ensure a healthy workplace for the international health care workforce.”Story Source:The above story is based on materials provided by University of British Columbia. Note: Materials may be edited for content and length.

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Mixed genes: Interactive world map of human genetic history reveals likely genetic impacts of historical events

When individuals from different groups interbreed, their offspring’s DNA becomes a mixture of the DNA from each admixing group. Pieces of this DNA are then passed along through subsequent generations, carrying on all the way to the present day. Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Oxford University and University College London (UCL) have now produced a global map detailing the genetic histories of 95 different populations across the world, spanning the last four millennia.The interactive world map that is accessible via the internet, details the histories of genetic mixing between each of the 95 populations across Europe, Africa, Asia and South America. It shows likely genetic impacts of historical events including European colonialism, the Mongol Empire, the Arab slave trade and European traders near the Silk Road mixing with people in China.The study, published this week in Science, is the first to simultaneously identify, date and characterise genetic mixing between populations. To do this, the researchers developed sophisticated statistical methods to analyse the DNA of 1490 individuals in 95 populations around the world. “DNA really has the power to tell stories and uncover details of humanity’s past,” said Simon Myers of Oxford University’s Department of Statistics and Wellcome Trust Centre for Human Genetics, co-senior author of the study. “Because our approach uses only genetic data, it provides information independent from other sources. Many of our genetic observations match historical events, and we also see evidence of previously unrecorded genetic mixing. For example, the DNA of the Tu people in modern China suggests that in around 1200CE, Europeans similar to modern Greeks mixed with an otherwise Chinese-like population. Plausibly, the source of this European-like DNA might be merchants travelling the nearby Silk Road.”The powerful technique, christened ‘Globetrotter’, provides insight into past events such as the genetic legacy of the Mongol Empire. …

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Coffee growing: More biodiversity, better harvest

Bees, birds and bats make a huge contribution to the high yields produced by coffee farmers around Mount Kilimanjaro – an example of how biodiversity can pay off. This effect has been described as result of a study now published in the „Proceedings of the Royal Society B“. It has been conducted by tropical ecologists of the University Wrzburg Biocenter, jointly with colleagues from the LOEWE Biodiversity and Climate Research Centre (BiK-F, Frankfurt/Main) and the Institute for experimental Ecology of the University of Ulm.A large amount of coffee is grown on Kilimanjaro, the East African massif almost 6000 meters high. The most traditional form of cultivation can be found in the gardens of the Chagga people. Hhere the sun-shy coffee trees and many other crop plants thrive in the shade of banana trees and other tall trees. However, the largest part of the coffee is grown on plantations. Usually, the plantations still feature a large number of shade trees. But these are progressively being chopped down because of the increasing replacement of “conventional coffee varieties, which rely on shade, by varieties that tolerate lots of sun and are more resistant to fungi,” explains Professor Ingolf Steffan-Dewenter, a tropical ecologist at the University of Wrzburg’s Biocenter. This crop intensification is expected to result in higher yields. The plantation harvests might however stagnate: If there are only few shade trees left, the habitat may become unsuitable for the animal species that pollinate the coffee, eat pests, and thereby help to improve the yield.Teamwork on the slopes of Mount KilimanjaroSteffan-Dewenter and his doctoral student Alice Classen therefore wanted to understand how bees, birds, bats and other animals contribute to pollination and to biological pest control in the coffee fields. …

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Stroke trigger more deadly for African-Americans

Infection is a stronger trigger of stroke death in African- Americans than in whites, a University of Michigan study shows.African-Americans were 39 times more likely to die of a stroke if they were exposed to an infection in the previous month when compared to other time periods while whites were four times more likely and Hispanics were five times more likely to die of stroke after an infection, according to the findings that appear online Feb. 7 in Neurology.The most frequent infections were urinary, skin, and respiratory tract infections and occurred within 30 days of a stroke.”Infection before stroke appears to be most lethal for black Americans,” says lead author Deborah A. Levine, M.D., M.P.H., assistant professor of medicine in the division of general medicine in the U-M Medical School. “We know that African- Americans have a much greater risk of dying from a stroke than white Americans, and we wanted to know if infection — which research suggests is a stroke trigger — might contribute to this disparity.”Infection is believed to promote the formation of blood clots and fat buildup in arteries, which block the artery and stop the flow of blood to the brain causing a stroke.Racial disparities in stroke death continue to widen in the U.S. where blacks are twice as likely to die from stroke as whites. The new findings show that all ethnic and racial groups had a higher risk of stroke following an infection but there were significant disparities in subsequent stroke deaths.Infection appeared to be a trigger of stroke death in whites and Hispanics as well, but it was particularly potent in African-Americans.Infection also occurred more often before stroke death in black Americans, with 70 percent experiencing an infection in the 30 days before stroke death compared to a frequency of 15 percent in months that were not followed by a stroke death. Infection occurred less often before stroke death in white Americans, with 45 percent experiencing an infection in the month before stroke death compared to a frequency of 19 percent in months that were not followed by a stroke death.Although earlier studies suggested that respiratory infections are the most potent triggers of stroke, Levine and colleagues found that urinary tract infections and skin infections seemed to be just as strong of triggers.The study was based on data from the Health and Retirement Study, a nationally-representative sample of older Americans that is conducted by the U-M Institute for Social Research on behalf of the National Institute of Aging.”Because of the higher stroke mortality rate among black Americans, there has been much attention on racial differences in vascular risk factors, like hypertension, and health behaviors but less attention on acute exposures that might contribute to racial differences in stroke deaths,” Levine says.”It is unclear why acute infection is more common, more lethal, or a more powerful trigger for stroke death in black Americans. Genetic risks, clinical, economic or environmental factors, and differences in access to health care are potential reasons. We need further studies to better understand this disparity so we can prevent more black Americans from dying of stroke, particularly after infection,” Levine says.Story Source:The above story is based on materials provided by University of Michigan Health System. Note: Materials may be edited for content and length.

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‘Severe reduction’ in killer whale numbers during last Ice Age

Whole genome sequencing has revealed a global fall in the numbers of killer whales during the last Ice Age, at a time when ocean productivity may have been widely reduced, according to researchers at Durham University. The scientists studied the DNA sequences of killer whale communities across the world.They found a severe decline in whale numbers leading to a bottleneck and consequent loss of genetic diversity approximately 40,000 years ago when large parts of Earth were covered in ice.The only exception to this was found in a killer whale population off the coast of South Africa that retained high variations in genetic diversity.As greater genetic diversity indicates larger population size, the researchers believe the South African community of killer whales escaped the bottleneck faced by other communities.They said an important factor could have been the Bengeula upwelling system — which delivers nutrient rich cold water to the oceans off South Africa — remaining stable despite the last glacial period.This nutrient rich water would have been able to sustain the supplies of fish and dolphins that killer whales in this part of the world feed on.The researchers added that other major upwelling systems around the world — the California current off North America; Humboldt off South America; and the Canary current off the coast of North Africa — were either disrupted or collapsed altogether during the last glacial or Pleistocene periods (40,000 to 2.5 million years ago).This could potentially have reduced the food supply to killer whales in these areas, leading to the fall in their numbers.Further research looking at the genetic diversity of the ocean’s other top predators, such as sharks, might potentially suggest a negative impact on their numbers too, the researchers suggested.Such a finding could support concerns about the potential impact changes in climate could have on ocean ecosystems in future, the researchers added.The reseach, funded by the Natural Environment Research Council in the UK, is published in the journal Molecular Biology and Evolution.During earlier glacial periods, killer whale populations were likely to have been stable in size, the researchers said.While it was likely that other factors affecting killer whale populations were “overlapping and complex,” the researchers ruled out hunting as an effect on the bottleneck in populations, as hunting by early man could not have happened on a sufficient enough scale to promote the global decline in killer whale numbers during that period.Corresponding author Professor Rus Hoelzel, in the School of Biological and Biomedical Sciences, said: “Killer whales have a broad world-wide distribution, rivalling that of humans. At the same time, they have very low levels of genetic diversity.”Our data suggest that a severe reduction in population size during the coldest period of the last ice age could help explain this low diversity, and that it could have been an event affecting populations around the world.”However, a global event is hard to explain, because regional modern-day killer whale populations seem quite isolated from each other. What could have affected multiple populations from around the world all at the same time?”The uniquely high levels of diversity we found for the population off South Africa suggest a possible explanation. These whales live in an environment that has been highly productive and stable for at least the last million years, while some data suggest that ocean productivity may have been reduced during the last glacial period elsewhere in the world.”If this is the case, then further research may suggest an impact on other ocean top predators during this time. It would also support concerns about the potential for climate disruptions to impact ocean ecosystems in future.”Story Source:The above story is based on materials provided by Durham University. Note: Materials may be edited for content and length.

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Gathering ‘wild’ food in the city: rethinking the role of foraging in urban ecosystem planning, management

Published today, these exploratory studies point to the importance for planners, managers and scholars to understand urban green spaces as not only providers of services, but also providers of material products.In the USA, influential landscape architects of the nineteenth and early twentieth century, such as Frederick Law Olmsted and his student Charles Eliot, advocated the creation of networks of urban parks connected to each other and, through river corridors, to green spaces beyond the boundaries of urban settlements. These planners argued that public spaces with large amounts of vegetation were essential elements of healthy, functional cities. These new landscapes emphasized aesthetics, relaxation, recreation, and refuge, reinforcing emerging notions about which human–nature interactions belonged in the city and which in the country.Productive practices were defined as rural and, therefore, inappropriate inside the city and city parks. Thus, cities such as Columbus, Ohio materially and discursively erased subsistence gardening and rules prohibiting foraging in parks became commonplace (McLain et al.) Further, development and maintenance of the great urban parks demanded centralization and professionalization of their care. Decision-making powers and management authority were vested in municipal governments and professional park managers.With the popularization of the concept of sustainable development in the late 1980s, planners saw the need for community involvement. They began to experiment with green space policies that explicitly seek to integrate social, economic, and ecological concerns in urban environments, recognizing and incorporating interstitial, raw, or ‘feral’ lands into park creation and protection. Such places, including the street trees and other vegetation that characterize these spaces, are important for meeting the community and ecosystem needs of low income urban neighborhoods that do not have large expanses of undeveloped land or existing parks. These shifts in the conceptualization of urban nature and human roles in it have, to some extent, created openings for the return of productive practices such as farming, horticulture and bee-keeping to public green spaces. However, urban foraging has received little attention in by planners of urban green spacesToday, foragers in this unique study In Baltimore, Seattle, NYC and Philadelphia ranged from less than 5 years in Baltimore to more than 80 years in Seattle. Income levels varied widely ranging from less than US$10,000 to more than US$250,000 and ethnic and racial diversity is common. …

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Alarming Mesothelioma Statistics For You to Know

Mesothelioma is not a very common disease with about 2000-3000 new cases seen in the US every year.-There was a gradual increase in the number of cases of newly diagnosed mesothelioma victims in the United States from the 1970’s to the 1990’s after which the number became fairly constant. After the year 2000 and beyond the number has likely been on the decrease.-Mesothelioma is more common in men. It is four times commoner in men than in women.-The number of new Mesothelioma cases is still increasing in European countries.-Mesothelioma commonly affects people over the age of 55 years, it is very rare to find Mesothelioma in people under the age of 55 years and its incidence increases with age, about 90% of people diagnosed with Mesothelioma are …

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New study finds spike in sugary drink consumption among California adolescents

Oct. 18, 2013 — While consumption of soda and other sugary drinks among young children in California is starting to decline, a new study released today shows an alarming 8 percent spike among adolescents, the biggest consumers of these beverages.Based on interviews with more than 40,000 California households conducted by the California Health Interview Survey (CHIS), the study, “Still Bubbling Over: California Adolescents Drinking More Soda and Other Sugar-Sweetened Beverages,” provides a comprehensive look at youth (2- to 17-year-olds) consumption of sugary drinks, charting consumption patterns from 2005-07 to 2011-12.The study, which also provides county-by-county youth consumption rates, was produced collaboratively by the UCLA Center for Health Policy Research and the California Center for Public Health Advocacy.The most encouraging finding was the dramatic drop in the proportion of young children drinking sugary beverages daily over the seven-year period. Only 19 percent of 2- to 5-year-olds drink a sugary beverage daily, a 30 percent decline from the 2005-07 reporting period. Among 6- to 11-year-olds, 32 percent were daily consumers in 2011-12, representing a 26 percent drop since 2005-07.Of greatest concern, however, is the significant rise among the biggest consumers of sugary drinks — adolescents (12- to 17-year-olds). Today, a full 65 percent of California adolescents drink sugary beverages daily, an 8 percent climb since 2005-07. And while the study’s authors point out that roughly the same proportion of these youth are drinking soda, 23 percent more are consuming energy and sports drinks every day.”California has made real progress in reducing the consumption of sugary beverages among young children,” said Dr. Susan Babey, the report’s lead author. “But teens are in trouble. Soda or sports drinks should be an occasional treat, not a daily habit. If this trend isn’t reversed, there may be costly consequences for teens, their families and the health care system in the form of increased obesity and diabetes.”Although the study does not directly examine the causes for the sugary spike among teens, Dr. …

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Elephants know what it means to point to something, no training required

Oct. 10, 2013 — When people want to direct the attention of others, they naturally do so by pointing, starting from a very young age. Now, researchers reporting in Current Biology, a Cell Press publication, on October 10 have shown that elephants spontaneously get the gist of human pointing and can use it as a cue for finding food. That’s all the more impressive given that many great apes fail to understand pointing when it’s done for them by human caretakers, the researchers say.”By showing that African elephants spontaneously understand human pointing, without any training to do so, we have shown that the ability to understand pointing is not uniquely human but has also evolved in a lineage of animal very remote from the primates,” says Richard Byrne of the University of St Andrews, noting that elephants are part of an ancient African radiation of animals, including the hyrax, golden mole, aardvark, and manatee. “What elephants share with humans is that they live in an elaborate and complex network in which support, empathy, and help for others are critical for survival. It may be only in such a society that the ability to follow pointing has adaptive value, or, more generally, elephant society may have selected for an ability to understand when others are trying to communicate with them, and they are thus able to work out what pointing is about when they see it.”Byrne and study first author Anna Smet were studying elephants whose “day job” is taking tourists on elephant-back rides near Victoria Falls, in southern Africa. The animals were trained to follow certain vocal commands, but they weren’t accustomed to pointing.”Of course, we always hoped that our elephants would be able to learn to follow human pointing, or we’d not have carried out the experiments,” Smet says. “What really surprised us is that they did not apparently need to learn anything. Their understanding was as good on the first trial as the last, and we could find no sign of learning over the experiment.”Elephants that were more experienced with humans, or those born in captivity, were no better than less-experienced, wild-born individuals when it came to following pointing gestures. Byrne and Smet say it is possible that elephants may do something akin to pointing as a means of communicating with each other, using their long trunk. …

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Using harsh verbal discipline with teens found to be harmful

Sep. 4, 2013 — Many American parents yell or shout at their teenagers. A new longitudinal study has found that using such harsh verbal discipline in early adolescence can be harmful to teens later. Instead of minimizing teens’ problematic behavior, harsh verbal discipline may actually aggravate it.The study, from researchers at the University of Pittsburgh and the University of Michigan, appears in the journal Child Development.Harsh verbal discipline happens when parents use psychological force to cause a child to experience emotional pain or discomfort in an effort to correct or control behavior. It can vary in severity from yelling and shouting at a child to insulting and using words to humiliate. Many parents shift from physical to verbal discipline as their children enter adolescence, and harsh verbal discipline is not uncommon. A nationally representative survey found that about 90 percent of American parents reported one or more instances of using harsh verbal discipline with children of all ages; the rate of the more severe forms of harsh verbal discipline (swearing and cursing, calling names) directed at teens was 50 percent.Few studies have looked at harsh verbal discipline in adolescence. This study found that when parents use it in early adolescence, teens suffer detrimental outcomes later. The children of mothers and fathers who used harsh verbal discipline when they were 13 suffered more depressive symptoms between ages 13 and 14 than their peers who weren’t disciplined in this way; they were also more likely to have conduct problems such as misbehaving at school, lying to parents, stealing, or fighting.Moreover, the study found that not only does harsh verbal discipline appear to be ineffective at addressing behavior problems in youths, it actually appears to increase such behaviors. Parents’ hostility increases the risk of delinquency by lowering inhibition and fostering anger, irritability, and belligerence in adolescents, the researchers found.The effect went the other way, too. …

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Genetic treasure hunting in sorghum may benefit crop improvement

Aug. 27, 2013 — A consortium of researchers from The University of Queensland, the Queensland Department of Agriculture, Fisheries and Forestry (DAFF Qld) and BGI has discovered that sorghum, a drought-tolerant African crop, holds vastly more genetic variation than previously reported. This study published in Nature Communications today provides an invaluable resource for the genetic improvement of sorghum and other grass species.Share This:Sorghum is not only a food and feed cereal crop, but also can be used as the basis of biofuel. Its resistance to heat and water stress allows it to grow in poor dryland regions as a staple food resource for 500 million poor people in Africa and Asia, alleviating both poverty and hunger. Sorghum is in the same family as rice (Oryza sativa), wheat (Triticum aestivumLinn) and maize (Zea mays), and it is expected to play an increasingly important role in feeding the world’s growing population. Furthermore, sorghum’s special features such as a small diploid genome and phenotypic diversity make it an ideal C4 grass model.By conducting whole-genome sequencing, the team obtained the genomic data of 44 sorghum lines to represent all major races of cultivated grain sorghum (Sorghum bicolor) in addition to its progenitors and the allopatric Asian species, S. propinquum. The analysis indicated that sorghum possesses a diverse primary gene pool but with decreased diversity in both landrace and improved groups. In addition to S. bicolor, a great untapped pool of diversity also exists in S. …

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Children exposed to lead three times more likely to be suspended from school

Aug. 14, 2013 — Children who are exposed to lead are nearly three times more likely to be suspended from school by the 4th grade than children who are not exposed, according to a new University of Wisconsin-Madison study funded jointly by the Robert Wood Johnson Foundation and the Wisconsin Partnership Program Education and Research Committee.”Students who are suspended from school are at greater risk of dropping out, twice as likely to use tobacco, and more likely to engage in violent behavior later in life,” says first author Michael Amato, a doctoral candidate in psychology and the Nelson Institute for Environmental Studies at UW-Madison. “Our study found that children exposed to lead were more than twice as likely to be suspended in the 4th grade, which means that lead may be more responsible for school discipline problems than many people realize.”Nationally, African-American students are three times more likely to be suspended than white students. The same discipline gap was found in the Wisconsin study, but 23 percent of the disparity was explained by differences in rates of lead exposure. Many previous studies have documented disparities in school discipline, but few have specified the underlying factors.”We knew that lead exposure decreases children’s abilities to control their attention and behavior, but we were still surprised that exposed children were so much more likely to be suspended,” said Sheryl Magzamen, a public health researcher who also worked on the UW-Madison study. Magzamen is now an assistant professor at the University of Oklahoma.Researchers cross-referenced medical data of nearly 4,000 children exposed to lead with 4th grade disciplinary records in the Milwaukee school district. They found that children who had been exposed to lead were nearly three times more likely to be suspended in the fourth grade than children who had not been exposed, even after controlling for income, race/ethnicity, and gender.Experiments on non-human animals prove that lead exposure causes decreased attention and decreased control over behavior when subjects are startled or touched. The study team reasoned that if exposed children were affected the same way, they would be more likely to engage in disruptive classroom behaviors that could result in suspension. The results of the study supported that hypothesis.”Children exposed to lead don’t get a fair start and it affects them for their whole lives,” adds study coauthor Colleen Moore, a UW-Madison psychology professor emerita affiliated with the Nelson Institute.According to the Centers for Disease Control and Prevention, African-American children are more than twice as likely as whites to have elevated lead levels. The reason, say the researchers, is that African-American children are more likely to live in lower-income neighborhoods and rental housing where lead remains in the buildings and soil, a common situation in major American cities.Moore notes that in the city of Milwaukee, lead abatement orders are currently active in more than 100 residential properties. …

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How will crops fare under climate change? Depends on how you ask

Aug. 14, 2013 — The damage scientists expect climate change to do to crop yields can differ greatly depending on which type of model was used to make those projections, according to research based at Princeton University. The problem is that the most dire scenarios can loom large in the minds of the public and policymakers, yet neither audience is usually aware of how the model itself influenced the outcome, the researchers said.The report in the journal Global Change Biology is one of the first to compare the agricultural projections generated by empirical models — which rely largely on field observations — to those by mechanistic models, which draw on an understanding of how crop growth and development are affected by the environment. Building on similar studies from ecology, the researchers found yet more evidence that empirical models may show greater losses as a result of climate change, while mechanistic models may be overly optimistic.The researchers ran an empirical and a mechanistic model to see how maize and wheat crops in South Africa — the world’s ninth largest maize producer, and sub-Saharan Africa’s second largest source of wheat — would fare under climate change in the years 2046 to 2065. Under the hotter, wetter conditions projected by the climate scenarios they used, the empirical model estimated that maize production could drop by 3.6 percent, while wheat output could increase by 6.2 percent. Meanwhile, the mechanistic model calculated that maize and wheat yields might go up by 6.5 and 15.2 percent, respectively.In addition, the empirical model estimated that suitable land for growing wheat would drop by 10 percent, while the mechanistic model found that it would expand by 9 percent. The empirical model projected a 48 percent expansion in wheat-growing areas, but the mechanistic reported only 20 percent growth. In regions where the two models overlapped, the empirical model showed declining yields while the mechanistic model showed increases. These wheat models were less accurate, but still indicative of the vastly different estimates empirical and mechanistic can produce, the researchers wrote.Disparities such as these aren’t just a concern for climate-change researchers, said first author Lyndon Estes, an associate research scholar in the Program in Science, Technology and Environmental Policy in Princeton’s Woodrow Wilson School of Public and International Affairs. Impact projections are crucial as people and governments work to understand and address climate change, but it also is important that people understand how they are generated and the biases inherent in them, Estes said. …

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