Improving understanding of valley-wide stream chemistry

A geostatistical approach for studying environmental conditions in stream networks and landscapes has been successfully applied at a valley-wide scale to assess headwater stream chemistry at high resolution, revealing unexpected patterns in natural chemical components.”Headwater streams make up the majority of stream and river length in watersheds, affecting regional water quality,” said Assistant Professor Kevin J. McGuire, associate director of the Virginia Water Resources Research Center in Virginia Tech’s College of Natural Resources and Environment. “However, the actual patterns and causes of variation of water quality in headwater streams are often unknown.””Understanding the chemistry of these streams at a finer scale could help to identify factors impairing water quality and help us protect aquatic ecosystems,” said Gene E. Likens, president emeritus and distinguished senior scientist emeritus with the Cary Institute of Ecosystem Studies and the University of Connecticut.Results of the study that used a new statistical tool to describe spatial patterns of water chemistry in stream networks are published in the April 21 issue of the Proceedings of the National Academies of Science by a team of ecosystem scientists, including McGuire and Likens.The data used in the new analysis consist of 664 water samples collected every 300 feet throughout all 32 tributaries of the 14-square-mile Hubbard Brook Valley in New Hampshire. The chemistry results were originally reported in 2006 in the journal Biogeochemistry by Likens and Donald C. Buso, manager of field research with the Cary Institute.McGuire and other members of the National Science Foundation’s Long-Term Ecological Research team at the Hubbard Brook Ecosystem Study decided that the huge, high-resolution dataset was ideal for a new statistical approach that examines how water flows both within the stream network and across the landscape.”The goal was to visualize patterns that no one has been able to quantify before now and describe how they vary within headwater stream networks,” said McGuire. “Some chemical constituents vary at a fine scale, that is patterns of chemical change occur over very short distances, for example several hundred feet, but some constituents vary over much larger scales, for example miles. Several chemical constituents that we examined even varied at multiple scales suggesting that nested processes within streams and across the landscape influence the chemistry of stream networks.””The different spatial relationships permit the examination of patterns controlled by landscape versus stream network processes,” the article reports. Straight-line and unconnected network spatial relationships indicate landscape influences, such as soil, geology, and vegetation controls of water chemistry, for instance. In contrast, flow-connected relationships provide information on processes affected within the flowing streams.The researchers are very familiar with the Hubbard Brook Valley and could point to the varying influences of the geology and distinct soil types, including areas of shallow acidic organic-rich soils.The findings revealed by the analysis technique showed how chemistry patterns vary across landscapes with two scales of variation, one around 1,500 feet and another at about 4 miles. …

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Growth of breast lifts outpacing implants 2-to-1, stats show

New statistics released today by the American Society of Plastic Surgeons (ASPS) show that breast lift procedures are growing at twice the rate of breast implant surgeries. Since 2000, breast lifts have grown by 70 percent, outpacing implants two-to-one. Breast implants are still by far the most performed cosmetic surgery in women, but lifts are steadily gaining. In 2013, more than 90,000 breast lift procedures were performed by ASPS member surgeons.”Many women are looking for a youthful breast by using the tissue they already have,” said ASPS President Robert X. Murphy, Jr., MD.According to the new statistics, women between the ages of 30-54 made up nearly 70 percent of the breast lift procedures performed in 2013. “The breast lift procedure is way up in my practice,” said Anne Taylor, MD, an ASPS-member plastic surgeon in Columbus, Ohio. “More women are coming to us who’ve had children, whose breast volume has decreased and who are experiencing considerable sagging,” she said. “For many of them, we are able to get rid of excess skin and lift the breasts back up where they’re supposed to be.”Kim Beckman of Casstown, Ohio is one of the women who went to Dr. Taylor. “Childbirth, breastfeeding and aging takes a toll on the body,” she said. …

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DNA from fossils reveal origin of Norwegian lemmings

A new ancient DNA study shows that the Norwegian lemming has a unique history. In contrast to other mammals in Fennoscandia, the Norwegian lemming may have survived the last Ice Age in the far north, sealed off from the rest of the world by gigantic ice sheets. This conclusion is drawn by an international team of researchers in an article published this week in the journal Molecular Ecology.The Norwegian lemming is an iconic small mammal that is unique to the Fennoscandian mountain tundra. Known for its dramatic fluctuations in population size, it is a keystone species in the mountain tundra ecosystem. But its origin has until now remained somewhat of a mystery.Twenty thousand years ago, Fennoscandia was covered by a thick ice sheet. Animals and plants in the region are therefore thought to originate from populations that lived to the south or east of the ice sheet, and colonised Fennoscandia as the ice melted. With this in mind, and international team of scientists, led by researchers at the Swedish Museum of Natural History, set out to investigate from where the Norwegian lemming originated at the end of the last Ice Age. To do this, the researchers retrieved and analysed ancient DNA from lemming populations that surrounded the ice sheet during the last Ice Age.- “We found that even though the populations surrounding the ice sheet were closely related to modern day lemmings, none of them were similar enough to be the direct ancestor of the Norwegian lemming,” says Love Daln, Associate Professor at the Swedish Museum of Natural History.After eliminating these populations as potential sources, the researchers concluded that the only remaining explanation was that the Norwegian lemming originates from a population that survived the last glaciation somewhere locally in Fennoscandia. The exact location where the Norwegian lemming could have survived the last glaciation is not clear, but likely places include coastal areas or mountain plateaus sticking out from the ice sheet.”The Norwegian lemming is the only endemic mammal in Fennoscandia, and its unusual origin is probably the reason why,” says Vendela Lagerholm, lead author on the study.Story Source:The above story is based on materials provided by Expertsvar. Note: Materials may be edited for content and length.

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Preserving large carnivores in ecosystem requires multifaceted approach

Carnivore management is not just a numbers game, Virginia Tech wildlife scientists assert in response to an article in the Jan. 10 issue of the journal Science that urged “minimum population densities be maintained for persistence of large carnivores, biodiversity, and ecosystem structure.””This type of approach may fail in social carnivore species,” said Kathleen Alexander, an associate professor of fisheries and wildlife conservation in the College of Natural Resources and Environment. “Predator management is incredibly complex and we need to be extremely cautious in applying blanket approaches which rely on securing some target number or density of individuals in an ecosystem.”The research-based argument appears in a letter in the March 14 issue of Science and an article abstract in the October 2013 issue of the journal Population Ecology.”Life history strategy, including number of offspring, lifespan, diet, and behavior that evolves from ecological pressures of the species in question should also guide management approaches,” wrote Alexander and Claire E. Sanderson, a postdoctoral associate in fisheries and wildlife conservation, in the Science letter.The research published in Population Ecology evaluated 45 solitary and social medium and large carnivore species and their key life history attributes, population trends, and identified the presence of factors that increase the potential for extinction.Disturbingly, 73 percent of carnivore species — both social and solitary — were declining, observed Sanderson, Sarah Jobbins, also a postdoctoral associate, and Alexander.”Social carnivores appeared to be particularly vulnerable with 45 percent threatened by infectious disease but only 3 percent of solitary carnivores similarly impacted,” they report. “In this, increased contact between individuals, disease-related mortality, and loss of individuals below some critical threshold seems to be the issue, pushing social carnivores closer to the brink of extinction.”Reporting on their research on social carnivores, Sanderson, Jobbins, and Alexander said in the article, “Highly cohesive social species, like African wild dog, require strict participation from all group members … in all areas of life, including predator avoidance, reproductive success, hunting, and survivorship. This life-history strategy can result in enhanced fitness benefits for the group, but also a higher critical threshold for extinction.””The number of individuals in the group then becomes the critical factor influencing population persistence,” said Sanderson.For example, rabies and distemper have caused local extinction of African wild dog in regions of Africa. Even in a large population, transmission of an infectious disease from only a few infected individuals can result in sufficient mortality to push groups below a critical threshold, ultimately threatening population persistence, the researchers report.It has been found in certain ecosystems that when wild dog packs are reduced to less than four individuals, they may be unable to rear pups because of trade-offs between specialized roles, such as pup guarding and hunting.”While aggregation of conspecifics may be beneficial for reproduction, hunting, and vigilance, social living is a disadvantage when it comes to transmission of disease,” according to Alexander’s research.Also a wildlife veterinarian, she cofounded the Centre for Conservation of African Resources: Animals, Communities and Land Use, in Kasane, Botswana and has been conducting research in Africa since the late 1980s.”Failure to consider the impacts of group dynamics may result in underestimation of critical threshold population sizes or densities required for population persistence,” Sanderson, Jobbins, and Alexander write.Alexander and Sanderson conclude in their letter in Science, “We urge consideration of life-history strategy and social behavior in the development of carnivore management strategy.”

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Makeup Minimalism: Achieving the natural beauty look

Learn more about Herbalife – Follow @Herbalife on Twitter- Like Herbalife on Facebook- What is Herbalife? More fitness advice – Watch ‘Fit Tips’ Videos on YouTube- Straightforward exercise advice- Get fit = be happy. Positivity advice Nutrition advice for you – Watch ‘Healthy Living’ on YouTube- Dieting advice you might like- Interesting weight loss articles Copyright © 2013 Herbalife International of America, Inc.

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Predators delay pest resistance to Bt crops

Crops genetically modified with the bacterium Bt (Bacillus thuringiensis) produce proteins that kill pest insects. Steady exposure has prompted concern that pests will develop resistance to these proteins, making Bt plants ineffective.Cornell research shows that the combination of natural enemies, such as ladybeetles, with Bt crops delays a pest’s ability to evolve resistance to these insecticidal proteins.“This is the first demonstrated example of a predator being able to delay the evolution of resistance in an insect pest to a Bt crop,” said Anthony Shelton, a professor of entomology at Cornell University’s New York State Agricultural Experiment Station in Geneva, N.Y., and a co-author of the paper. Xiaoxia Liu, a visiting scientist from China Agricultural University who worked in the Shelton lab, is the lead author on the paper published in the journal PLoS One.Bt is a soil bacterium that produces proteins that are toxic to some species of caterpillars and beetles when they are ingested, but have been proven safe to humans and many natural enemies, including predaceous ladybirds. Bt genes have been engineered into a variety of crops to control insect pests.Since farmers began planting Bt crops in 1996 with 70 million hectares planted in the United States in 2012, there have been only three clear-cut cases in agriculture of resistance in caterpillars, and one in a beetle. “Resistance to Bt crops is surprisingly uncommon,” said Shelton.To delay or prevent insect pests from evolving resistance to Bt crops, the U.S. Environmental Protection Agency promotes the use of multiple Bt genes in plants and the practice of growing refuges of non-Bt plants that serve as a reservoir for insects with Bt susceptible genes.“Our paper argues there is another factor involved: the conservation of natural enemies of the pest species,” said Shelton. These predators can reduce the number of potentially resistant individuals in a pest population and delay evolution of resistance to Bt.In the study, the researchers set up large cages in a greenhouse. Each cage contained Bt broccoli and refuges of non-Bt broccoli. They studied populations of diamondback moth (Plutella xylostella) larvae, a pest of broccoli, and their natural enemies, ladybird beetles (Coleomegilla maculata), for six generations.Cages contained different combinations of treatments with and without predators, and with and without sprayed insecticides on the non-Bt refuge plants. Farmers commonly spray insecticides on refuge plants to prevent loss by pests, but such sprays can kill predators and prey indiscriminately.The results showed that diamondback moth populations were reduced in the treatment containing ladybird beetles and unsprayed non-Bt refuge plants. …

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Mechanism of crude oil heart toxicity on fish revealed from oil spill research

Scientists from Stanford University and the National Oceanic and Atmospheric Administration (NOAA) have discovered that crude oil interferes with fish heart cells. The toxic consequence is a slowed heart rate, reduced cardiac contractility and irregular heartbeats that can lead to cardiac arrest and sudden cardiac death.The research, published in the Feb. 14 issue of Science, is part of the ongoing Natural Resource Damage Assessment of the April 2010 Deepwater Horizon oil spill.While crude oil is known to be cardiotoxic to developing fish, the physiological mechanisms underlying its harmful effects were unclear. Stanford and NOAA scientists studying the impact of crude oil from the Deepwater Horizon spill on tuna discovered that it interrupts the ability of fish heart cells to beat effectively.Crude oil is a complex mixture of chemicals, some of which are known to be toxic to marine animals. Past research has focused in particular on “polycyclic aromatic hydrocarbons” (PAHs), which can also be found in coal tar, creosote, air pollution and stormwater runoff from land. In the aftermath of an oil spill, PAHs can persist for many years in marine habitats and cause a variety of adverse environmental effects.The researchers report that oil interferes with cardiac cell excitability, contraction and relaxation — vital processes for normal beat-to-beat contraction and pacing of the heart.Their tests revealed that very low concentrations of crude oil disrupt the specialized ion channel pores — where molecules flow in and out of the heart cells — that control heart rate and contraction in the cardiac muscle cell.This cyclical signaling pathway in cells throughout the heart is what propels blood out of the pump on every beat. The protein components of the signaling pathway are highly conserved in the hearts of most animals, including humans.The researchers found that oil blocks the potassium channels distributed in heart cell membranes, increasing the time to restart the heart on every beat. This prolongs the normal cardiac action potential, and ultimately slows the heartbeat. The potassium ion channel impacted in the tuna is responsible for restarting the heart muscle cell contraction cycle after every beat, and is highly conserved throughout vertebrates, raising the possibility that animals as diverse as tuna, turtles and dolphins might be affected similarly by crude oil exposure. Oil also resulted in arrhythmias in some ventricular cells.”The ability of a heart cell to beat,” explained Barbara Block, a professor of marine sciences at Stanford, “depends on its capacity to move essential ions like potassium and calcium into and out of the cells quickly. …

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Macro-portrait of future bird and wetland scenarios under climate change

Using a mountain of satellite photographic data and decades of waterfowl counts, a Texas Tech University biologist said she and others have found a correlation with the amount of waterfowl and the amount of wetlands available across the plains from Canada to Texas.More wetlands meaning more waterfowl may sound like a no-brainer, but researchers were able to land at conclusion using macrosystems ecology said Nancy McIntyre, a professor of biological sciences and curator of birds at the Natural Science Research Laboratory.The research appeared in a special edition of the peer-reviewed journal, Frontiers in Ecology and the Environment, dedicated to macrosystems ecology.”The novelty of what we’re doing is in taking the weather data from the past to be able to say certain types of precipitation conditions led to X amount of available wetlands, which was associated with Y number of birds,” McIntyre said. “If future climate scenarios say we should get fewer but more extreme precipitation events, then we can estimate how many wetlands and birds will be around in the future, so long as no more wetlands are converted into farm use or turned into neighborhoods. That’s work in progress. It sounds straightforward, but it has never been done because of the complexity and the massive amount of data used here.”Macrosystems ecology is a new and emerging science using large amounts of information that are analyzed by faster and smarter computers to not only create greater understanding of how habitats interact, but also make better predictions about how these systems may react in the face of global climate change, she said.”A change in the number of wetlands available can cascade in to the variety and numbers of birds, as well as amphibians, dragonflies and a number of other animals,” McIntyre said. “In the United States, we’ve lost about 50 percent of the nation’s original wetlands in the past 200 years. The losses are particularly bad in the Great Plains, where about 98 percent of the wetlands have disappeared since 1986. With climate change on the horizon, we’re trying to understand how these wetlands and the animals that use them interact.”The research was part of a $1.6 million grant from the National Science Foundation. McIntyre and others looked at freshwater wetlands across the Great Plains from the prairie potholes carved by glacial activity in the north, through the Rainwater Basin of Nebraska down to the playa lakes of the South Plains.”They call it the duck factory of the world,” McIntyre said. “Most of the ducks breed up there and overwinter down here. But there are about 300 species of regularly occurring, breeding land birds in the Great Plains, many of which use these wetlands.”Researchers studied photos from satellites that passed over the same area of land every 16 days, she said. …

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Humans, urban landscapes increase illness in songbirds, researchers find

Humans living in densely populated urban areas have a profound impact not only on their physical environment, but also on the health and fitness of native wildlife. For the first time, scientists have found a direct link between the degree of urbanization and the prevalence and severity of two distinct parasites in wild house finches.The findings are published in the Feb. 4 issue of the journal PLOS ONE.A team of researchers from Arizona State University made the discovery while investigating intestinal parasites (Isospora sp.) and the canarypox virus (Avipoxvirus) found in house finches. The group also studied the effects of urbanization on the stress response system of the finches.Specifically, the team studied male house finches found at seven sites throughout Maricopa County in central Arizona. Each site varied in the number of people living within one kilometer (about five-eighths of a mile) — from nearly a dozen to over 17 thousand.Researchers also considered whether the soil in each location had been disturbed and the vegetation cultivated or left in a natural state. In all, they quantified 13 different urbanization factors. They also assessed the potential relationship between oxidative stress, the degree of urbanization and parasitic infections to see whether increased infections are associated with increased stress levels.”Several studies have measured parasite infection in urban animals, but surprisingly we are the first to measure whether wild birds living in a city were more or less infected by a parasite and a pathogen, as well as how these infections are linked to their physiological stress,” said Mathieu Giraudeau, a post-doctoral associate who previously worked with Kevin McGraw, ASU associate professor with the School of Life Sciences. Giraudeau now works with the University of Zurich in Switzerland.”We also capitalized on data gathered by the Central Arizona Phoenix-Long Term Ecological Research program to accurately measure the degree to which the landscapes at each study site were natural or disturbed by humans,” added Giraudeau.House finches (Haemorhous mexicanus) are native to the desert southwest in the U.S., but are now found abundantly throughout North America. Male finches are five to six inches long and have colorful red, orange or yellow crown, breast and rump feathers.Emerging infectious diseases transmitted from animals to humansAccording to the study, more than half of the world’s population now lives in cities. Natural habitats and ecosystems have been dramatically altered from their original states, and there is rising concern about the spread of diseases that can be passed from urban wildlife to humans. …

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Converting land to agriculture reduces carbon uptake, study shows

University of Montana researchers examined the impact that converting natural land to cropland has on global vegetation growth, as measured by satellite-derived net primary production, or NPP. They found that measures of terrestrial vegetation growth actually decrease with agricultural conversion, which has important implications for terrestrial carbon storage.Postdoctoral researcher Bill Smith and UM faculty members Steve Running and Cory Cleveland, along with a former UM postdoctoral researcher and current USGS scientist Sasha Reed, used estimates of agricultural NPP and satellite-derived estimates of natural NPP to evaluate the impact of expanding agricultural land to meet needs for food and fiber. Terrestrial NPP represents the total annual growth of vegetation on the land, which is a critical factor that helps determine how much carbon can be absorbed and stored from the atmosphere.Their results show that agricultural conversion has reduced that productivity by approximately 7 percent. A small percentage of intensively managed, irrigated or fertilized agricultural land shows an increase in productivity. However, productivity is reduced in 88 percent of agricultural lands globally, with the largest reductions in former tropical forests and savannas.”Current forecasts suggest that global food demand will likely double by 2050,” Smith said. “We hope that this research will help to identify strategies that, from a carbon balance perspective, should be avoided due to the potential for severe degradation of global vegetation growth and carbon storage.”The research was published in Geophysical Research Letters and highlighted in the February 2014 issue of Nature Geoscience.Story Source:The above story is based on materials provided by The University of Montana. Note: Materials may be edited for content and length.

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Nutritional supplement improves cognitive performance in older adults, study finds

Declines in the underlying brain skills needed to think, remember and learn are normal in aging. In fact, this cognitive decline is a fact of life for most older Americans.Therapies to improve the cognitive health of older adults are critically important for lessening declines in mental performance as people age. While physical activity and cognitive training are among the efforts aimed at preventing or delaying cognitive decline, dietary modifications and supplements have recently generated considerable interest.Now a University of South Florida (USF) study reports that a formula of nutrients high in antioxidants and other natural components helped boost the speed at which the brains of older adults processed information.The USF-developed nutritional supplement, containing extracts from blueberries and green tea combined with vitamin D3 and amino acids, including carnosine, was tested by the USF researchers in a clinical trial enrolling 105 healthy adults, ages 65 to 85.The two-month study evaluated the effects of the formula, called NT-020, on the cognitive performance of these older adults, who had no diagnosed memory disorders.Those randomized to the group of 52 volunteers receiving NT-020 demonstrated improvements in cognitive processing speed, while the 53 volunteers randomized to receive a placebo did not. Reduced cognitive processing speed, which can slow thinking and learning, has been associated with advancing age, the researchers said.The study, conducted at the USF Health Byrd Alzheimer’s Institute, appears in the current issue of Rejuvenation Research (Vol. 17 No. 1, 2014). Participants from both groups took a battery of memory tests before and after the interventions.”After two months, test results showed modest improvements in two measures of cognitive processing speed for those taking NT-020 compared to those taking placebo,” said Brent Small, PhD, a professor in USF’s School of Aging Studies. “Processing speed is most often affected early on in the course of cognitive aging. Successful performance in processing tasks often underlies more complex cognitive outcomes, such as memory and verbal ability.”Blueberries, a major ingredient in the NT-020 formula, are rich in polyphenols, a type of antioxidant containing a polyphenolic, or natural phenol substructure.”The basis for the use of polyphenol-rich nutritional supplements as a moderator of age-related cognitive decline is the age-related increase in oxidative stress and inflammation,” said study co-principal investigator Paula C. Bickford, PhD, a professor in the Department of Neurosurgery and Brain Repair, USF Health Morsani College of Medicine, and senior research career scientist at the James A. …

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Meal times could have a significant effect on the levels of triglycerides in the liver

New findings in mice suggest that merely changing meal times could have a significant effect on the levels of triglycerides in the liver. The results of this Weizmann Institute of Science study, recently published in Cell Metabolism, not only have important implications for the potential treatment of metabolic diseases, they may also have broader implications for most research areas in the life sciences.Many biological processes follow a set timetable, with levels of activity rising and dipping at certain times of the day. Such fluctuations, known as circadian rhythms, are driven by internal “body clocks” based on an approximately 24-hour period — synchronized to light-dark cycles and other cues in an organism’s environment. Disruption to this optimum timing system in both animal models and in humans can cause imbalances, leading to such diseases as obesity, metabolic syndrome and fatty liver. Night-shift workers, for example, have been shown to have higher incidence of these diseases.In studying the role of circadian rhythm in the accumulation of lipids in the liver, postdoctoral fellow Yaarit Adamovich and the team in the lab of Dr. Gad Asher of the Weizmann Institute’s Biological Chemistry Department, together with scientists from Dr. Xianlin Han’s lab in the Sanford-Burnham Medical Research Institute, Orlando, US, quantified hundreds of different lipids present in the mouse liver. They discovered that a certain group of lipids, namely the triglycerides (TAG), exhibit circadian behavior, with levels peaking about eight hours after sunrise. The scientists were astonished to find, however, that daily fluctuations in this group of lipids persist even in mice lacking a functional biological clock, albeit with levels cresting at a completely different time — 12 hours later than the natural schedule.”These results came as a complete surprise: One would expect that if the inherent clock mechanism is ‘dead,’ TAG could not accumulate in a time-dependent fashion,” says Adamovich. So what was making the fluctuating lipid levels “tick” if not the clocks? …

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Sucker-footed fossils broaden bat map: Fossilized teeth show bat family belongs to primitive lineage, had broad range

Today, Madagascar sucker-footed bats live nowhere outside their island home, but new research shows that hasn’t always been the case. The discovery of two extinct relatives in northern Egypt suggests the unusual creatures, which evolved sticky footpads to roost on slick surfaces, are primitive members of a group of bats that evolved in Africa and ultimately went on to flourish in South America.A team of researchers described the two bat species from several sets of fossilized jawbones and teeth unearthed in the Sahara. The findings, reported Feb. 4 in the open-access journal PLOS ONE, represent the first formal description of the family in the fossil record and show the sucker-footed bat family to be at least 36 million years older than previously known.”We’ve assumed for a long time that they were an ancient lineage based on DNA sequence studies that have placed them close to very old groups in the bat family tree,” said Nancy Simmons, co-author and curator-in-charge of the American Museum of Natural History’s Mammalogy Department. But until now, scientists lacked any fossil evidence to confirm it.The discovery also shows that, like many island-dwelling, relict species, sucker-footed bats have not always been confined to their present range — they once swooped through the African skies.Today, the sucker-footed bats consist of two species, Myzopoda aurita and M. schliemanni, endemic to Madagascar. In contrast to almost all other bats, they don’t cling upside-down to cave ceilings or branches. Sucker-footed bats roost head-up, often in the furled leaves of the traveler’s palm, a plant in the bird-of-paradise family. To stick to such a smooth surface, the bats evolved cup-like pads on their wrists and ankles. Scientists previously suspected the pads held the bats up by suction, but recent research has demonstrated the bats instead rely on wet adhesion, like a tree frog.”The fossils came from a fascinating place out in the Egyptian desert,” said Gregg Gunnell, director of the Duke University Lemur Center’s Division of Fossil Primates. …

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Organic farms support more species, researchers find

On average, organic farms support 34% more plant, insect and animal species than conventional farms, say Oxford University scientists. Researchers looked at data going back 30 years and found that this effect has remained stable over time and shows no signs of decreasing.’Our study has shown that organic farming, as an alternative to conventional farming, can yield significant long-term benefits for biodiversity,’ said Sean Tuck of Oxford University’s Department of Plant Sciences, lead author of the study. ‘Organic methods could go some way towards halting the continued loss of diversity in industrialized nations.’For pollinators such as bees, the number of different species was 50% higher on organic farms, although it is important to note that the study only looked at ‘species richness’.’Species richness tells us how many different species there are but does not say anything about the total number of organisms,’ said Mr Tuck. ‘There are many ways to study biodiversity and species richness is easy to measure, providing a useful starting point. Broadly speaking, high species richness usually indicates a variety of species with different functions. Taking the example of bees, species richness would tell us how many different species of bee were on each farm but not the total number of bees.’The study, published this week in the Journal of Applied Ecology, looked at data from 94 previous studies covering 184 farm sites dating back to 1989. The researchers re-analysed the data using satellite imagery to estimate the land use in the landscape surrounding each farm site to see if this had an impact on species richness. The study was carried out by scientists at Oxford University and the Swedish University of Agricultural Sciences, and was partly funded by the Natural Environment Research Council (NERC).Organic farms had a bigger impact on species richness when the land around them was more intensively farmed, particularly when it contained large tracts of arable land. Arable land is defined as land occupied by crops that are sown and harvested in the same agricultural year, such as wheat or barley.’We found that the impacts of organic farms on species richness were more pronounced when they were located in intensively farmed regions,’ said Dr Lindsay Turnbull of Oxford University’s Department of Plant Sciences, senior author of the study. ‘This makes sense because the biodiversity benefits of each organic farm will be diluted in clusters of organic farms compared to an organic “island” providing rich habitats in a sea of pesticide-covered conventional fields. …

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HomeLogic: natural cleaning products (giveaway)

Product was received from Natural HomeLogic to facilitate this review of natural cleaning products. All opinions are my own.I think my husband and I have always been environmentally conscious—his civil engineering degree is with a specialty in environmental and one of my BS degrees is in environmental science—but never so much as when we had kids. It’s just something about being solely responsible for the well-being of a helpless, tiny human being! We made a lot of changes, but one that was a priority was making sure anything that went on their skin was safe and natural. This includes skincare products like soaps and shampoos and cleaning supplies (that are inhaled or end up on their skin as they move around the house—and then possibly …

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Nine steps to save waterways and fisheries identified by researchers

The key to clean water and sustainable fisheries is to follow nine guiding principles of water management, says a team of Canadian biologists.Fish habitats need ecosystems that are rich in food with places to hide from predators and lay eggs, according to the framework published today in the journal Environmental Reviews.Humans have put key freshwater ecosystems at risk because of land development and the loss of the vegetation along rivers and streams, says John Richardson, a professor in the Dept. of Forest and Conservation Sciences at the University of British Columbia, one of 15 freshwater biologists who created the framework to help protect fish and ecosystems into the future.”Fish are strongly impacted when nutrients, sediments or pollutants are added to their habitat. We cannot protect fish without maintaining a healthy freshwater ecosystem,” says Richardson, who led the policy section on protecting fish habitats. Other policy sections addressed areas such as climate change and biodiversity.Connecting waterways are also critical for healthy ecosystems, says Richardson. “If fish can’t get to breeding or rearing areas because of dams, culverts, water intakes or other changes to their habitats, then the population will not survive,” he says.With more pressure on Canada’s freshwater ecosystems, Richardson and his colleagues wanted to create a framework of evidence-based principles that managers, policy makers and others could easily use in their work. “It’s a made in Canada solution, but the principles could be applied anywhere in the world,” he says.BACKGROUNDERHealthy freshwater ecosystems are shrinking and reports suggest that the animals that depend on them are becoming endangered or extinct at higher rates than marine or terrestrial species, says Richardson. Humans also depend on these ecosystems for basic resources like clean drinking water and food as well as economic activity from the natural resource sector, tourism and more.The components of a successful management plan include:Protect and restore habitats for fisheries Protect biodiversity as it enhances resilience and productivity Identify threats to ecosystem productivity Identify all contributions made by aquatic ecosystems Implement ecosystem based-management of natural resources while acknowledging the impact of humans Adopt a precautionary approach to management as we face uncertainty Embrace adaptive management — environments continue to change so research needs to be ongoing for scientific evidence-based decision making Define metrics that will indicate whether management plans are successful or failing Engage and consult with stakeholders Ensure that decision-makers have the capacity, legislation and authority to implement policies and management plans. These recommendations are based on nine principles of ecology:Acknowledge the physical and chemical limits of an ecosystem Population dynamics are at work and there needs to be a minimum number of fish for the population to survive Habitat quantity and quality are needed for fish productivity Connecting habitats is essential for movement of fish and their resources The success of freshwater species is influenced by the watershed Biodiversity enhances ecosystem resilience and productivity Global climate change affects local populations of fish Human impacts to the habitat affect future generations of fish Evolution is important to species survival 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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Mixing nanoparticles to make multifunctional materials

Oct. 20, 2013 — Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have developed a general approach for combining different types of nanoparticles to produce large-scale composite materials. The technique, described in a paper published online by Nature Nanotechnology on October 20, 2013, opens many opportunities for mixing and matching particles with different magnetic, optical, or chemical properties to form new, multifunctional materials or materials with enhanced performance for a wide range of potential applications.The approach takes advantage of the attractive pairing of complementary strands of synthetic DNA-based on the molecule that carries the genetic code in its sequence of matched bases known by the letters A, T, G, and C. After coating the nanoparticles with a chemically standardized “construction platform” and adding extender molecules to which DNA can easily bind, the scientists attach complementary lab-designed DNA strands to the two different kinds of nanoparticles they want to link up. The natural pairing of the matching strands then “self-assembles” the particles into a three-dimensional array consisting of billions of particles. Varying the length of the DNA linkers, their surface density on particles, and other factors gives scientists the ability to control and optimize different types of newly formed materials and their properties.”Our study demonstrates that DNA-driven assembly methods enable the by-design creation of large-scale ‘superlattice’ nanocomposites from a broad range of nanocomponents now available-including magnetic, catalytic, and fluorescent nanoparticles,” said Brookhaven physicist Oleg Gang, who led the research at the Lab’s Center for Functional Nanomaterials (CFN). “This advance builds on our previous work with simpler systems, where we demonstrated that pairing nanoparticles with different functions can affect the individual particles’ performance, and it offers routes for the fabrication of new materials with combined, enhanced, or even brand new functions.”Future applications could include quantum dots whose glowing fluorescence can be controlled by an external magnetic field for new kinds of switches or sensors; gold nanoparticles that synergistically enhance the brightness of quantum dots’ fluorescent glow; or catalytic nanomaterials that absorb the “poisons” that normally degrade their performance, Gang said.”Modern nano-synthesis methods provide scientists with diverse types of nanoparticles from a wide range of atomic elements,” said Yugang Zhang, first author of the paper. “With our approach, scientists can explore pairings of these particles in a rational way.”Pairing up dissimilar particles presents many challenges the scientists investigated in the work leading to this paper. To understand the fundamental aspects of various newly formed materials they used a wide range of techniques, including x-ray scattering studies at Brookhaven’s National Synchrotron Light Source (NSLS) and spectroscopy and electron microcopy at the CFN.For example, the scientists explored the effect of particle shape. …

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Asbestos in the Drinking Water?

Asbestos in the Drinking Water?When reading material about the uses of asbestos and mesothelioma-linked materials, you will mostly encounter facts about asbestos in the environment that can become airborne and lead to mesothelioma. However, largely because of the decay of cement water mains and the erosion of natural deposits, asbestos can also contaminate drinking water. Water suppliers are required by law to conduct routine monitoring to make sure that water levels are below the maximum contaminant level (MCL). According to the EPA, the MCL for asbestos in drinking water is 7 MFL. While MFL is not defined in the Basic Information about Asbestos in Drinking Water on the EPA website, the National Primary Drinking Water Regulations, as printed in the EPA publication, “Water On Tap: What …

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How tiny organisms make a big impact on clean water

Oct. 15, 2013 — Nearly every body of water, from a puddle or a pond to a vast ocean, contains microscopic organisms that live attached to rocks, plants, and animals. These so-called sessile suspension feeders are critical to aquatic ecosystems and play an important role in cleaning up environmental contaminants by consuming bacteria. A study published by Cell Press on October 15 in the Biophysical Journal reveals that by actively changing the angle of their bodies relative to the surfaces, these feeders overcome the physical constraints presented by underwater surfaces, maximize their access to fresh, nutrient-rich water, and filter the surrounding water.Share This:”Our findings will allow scientists to make better estimates about how much water each of these tiny organisms can filter and clean, which can help us to make better estimates about how quickly bodies of water can recover after contamination caused by oil spills and sewage leaks,” says lead study author Rachel Pepper of the University of California, Berkeley.Microscopic sessile suspension feeders, which are made up of only one or a few cells, use hair-like or whip-like appendages to draw nutrient-rich fluid toward their bodies, filtering up to 25% of the seawater in coastal areas each day. Because they live attached to surfaces, they potentially face several challenges while they feed. For example, currents encounter resistance and slow down when they flow across these surfaces, interfering with the ability of suspension feeders to efficiently extract nutrients. The way that currents interact with surfaces may also cause water to recirculate around suspension feeders after the nutrients have been consumed.To examine how the tiny organisms overcome these challenges, Pepper and her team used a combination of experiments and calculations. They observed that a protozoan called Vorticella convallaria actively changes its body orientation relative to the surface to which it is attached, in contrast to previous models, which assumed that sessile suspension feeders always feed at a perpendicular angle. The new model revealed that feeding at a parallel or other non-perpendicular angle substantially increases the amount of nutrients the organisms can extract from their surroundings by reducing both fluid resistance and the recirculation of nutrient-depleted water.”We know very little about the processes microbes use to remove and recycle contaminants,” Pepper says. “Our study shows that fluid flows at the scale of individual small organisms, when aggregated, can be important contributors to maintaining the quality of natural waters.”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 Cell Press, via EurekAlert!, a service of AAAS. …

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Plant community plays key role in controlling greenhouse gas emissions from carbon rich moorlands

Sep. 18, 2013 — Different moorland plants, particularly heather and cotton grass, can strongly influence climate warming effects on greenhouse gas emissions, researchers from Lancaster University, The University of Manchester and the Centre for Ecology & Hydrology have discovered.The findings, published this week in the journal Ecology Letters, show valuable carbon stores, which lie deep below peaty moorlands, are at risk from changes in climate and from land management techniques that alter plant diversity.But the study found that the make-up of the plant community could also play a key role in controlling greenhouse gas emissions from these carbon rich ecosystems, as not all vegetation types respond in the same way to warming.The research, supported by a Natural Environment Research Council (NERC) grant, took place at Moor House National Nature Reserve, high up in the North Pennines, a long-term, ecological monitoring site for the UK Environmental Change Network.The newly set up experimental site manipulated both temperature and the composition and diversity of vegetation at the same time, allowing the team to study the combined effects of these global change phenomena for the first time.Temperatures were increased by around 1°C using open-topped, passive warming chambers, specially built on site, which mimicked the predicted effects of global warming.The researchers found that when heather was present, warming increased the amount of CO2 taken up from the atmosphere, making the ecosystem a greater sink for this greenhouse gas. However, when cotton grass was present, the CO2 sink strength of system decreased with warming, and the amount of methane released increased.Professor Richard Bardgett, who led the research team, and has recently moved to The University of Manchester, said: “What surprised us was that changes in vegetation, which can result from land management or climate change itself, also had such a strong impact on greenhouse gas emissions and even changed the way that warming affected them.”In other words, the diversity and make-up of the vegetation, which can be altered by the way the land is farmed, can completely change the sink strength of the ecosystem for carbon dioxide. This means that the way we manage peat land vegetation will strongly influence the way that peat land carbon sink strength responds to future climate change.”Dr Sue Ward, the Senior Research Associate for the project at Lancaster Environment Centre, said: “Setting up this experiment allowed us to test how greenhouse gas emissions are affected by a combination of changes in climate and changes in plant communities.”By taking gas samples every month of the year, we were able to show that the types of plants growing in these ecosystems can modify the effects of increase in temperature.”Dr Ward said the study would be of interest and relevance to ecological and climate change scientists and policy makers.”Changes in vegetation as well as physical changes in climate should be taken into account when looking at how global change affects carbon cycling,” she added. “Otherwise a vital part is missing — the biology is a key ingredient.”Professor Nick Ostle, from the Centre for Ecology & Hydrology, a joint partner in the research, said: “This ‘real-world’ study of the response of peat lands to climate change is unique, making these findings even more important.”It seems that the identity of the plants present in these landscapes will exert a strong influence on the effect of climate warming on soil CO2 emissions back to the atmosphere. If this is true then we can expect similar responses in other carbon rich systems in the Arctic and Boreal regions.”

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