Intensity of hurricanes: New study helps improve predictions of storm intensity

They are something we take very seriously in Florida — hurricanes. The names roll off the tongue like a list of villains — Andrew, Charlie, Frances and Wilma.In the past 25 years or so, experts have gradually been improving prediction of the course a storm may take. This is thanks to tremendous advancements in computer and satellite technology. While we still have the “cone of uncertainty” we’ve become familiar with watching television weather reports, today’s models are more accurate than they used to be.The one area, however, where there is still much more to be researched and learned is in predicting just how intense a storm may be. While hurricane hunter aircraft can help determine wind speed, velocity, water temperature and other data, the fact is we often don’t know why or how a storm gets stronger or weaker. There has been virtually no progress in hurricane intensity forecasting during the last quarter century.But, thanks to new research being conducted, all that’s about to change.”The air-water interface — whether it had significant waves or significant spray — is a big factor in storm intensity,” said Alex Soloviev, Ph.D., a professor at Nova Southeastern University’s Oceanographic Center. “Hurricanes gain heat energy through the interface and they lose mechanical energy at the interface.”Soloviev is also an Adjunct Professor at the University of Miami Rosenstiel School of Marine and Atmospheric Science (UM RSMAS) and a Fellow at the Cooperative Institute for Marine and Atmospheric Studies (CIMAS.) He and his fellow researchers used a computational fluid dynamics model to simulate microstructure of the air-sea interface under hurricane force winds. In order to verify these computer-generated results, the group conducted experiments at the UM’s Rosenstiel School Air-Sea Interaction Salt Water Tank (ASIST) where they simulated wind speed and ocean surface conditions found during hurricanes.The study “The Air-Sea Interface and Surface Stress Under Tropical Cyclones” was published in the June 16, 2014 issue of the journal Nature Scientific Reports. Soloviev was the lead author of this study, which was conducted by a multi-institutional team including Roger Lukas (University of Hawaii), Mark Donelan and Brian Haus (UM RSMAS), and Isaac Ginis (University of Rhode Island.)The researchers were surprised at what they found. Under hurricane force wind, the air-water interface was producing projectiles fragmenting into sub millimeter scale water droplets. …

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Dingo poisoning should be stopped to protect native Australian mammals

Poisoning of dingoes — the top predators in the Australian bush — has a deleterious effect on small native mammals such as marsupial mice, bandicoots and native rodents, a UNSW-led study shows.The research, in forested National Parks in NSW, found that loss of dingoes after baiting is associated with greater activity by foxes, which prey on small marsupials and native rodents.As well, the number of kangaroos and wallabies increases when dingoes, also known as wild dogs, disappear. Grazing by these herbivores reduces the density of the understorey vegetation in which the small ground-dwelling mammals live.”Dingoes should not be poisoned if we want to halt the loss of mammal biodiversity in Australia. We need to develop strategies to maintain the balance of nature by keeping dingoes in the bush, while minimising their impacts on livestock,” says the senior author, UNSW’s Dr Mike Letnic.The study is published in the journal Proceedings of the Royal Society B.The researchers surveyed seven pairs of forested sites within conservation reserves managed by the NSW National Parks and Wildlife Service.Baiting of dingoes with 1080 poison had been carried out at one location in each pair, but not the other. Apart from the resulting difference in the number of dingoes present, the pairs of locations had similar eucalypt coverage, geology and landforms, and were less than 50 kilometres apart.”This provided an extraordinary natural experiment to compare the impact of the loss of dingoes on a forested ecosystem,” says Dr Letnic, an ARC Future Fellow in the Centre for Ecosystem Science in the UNSW School of Biological, Earth and Environmental Sciences.It is the first study to show how removing large carnivores can result in simultaneous population outbreaks of herbivores and smaller predators. And that these population outbreaks, in turn, can have deleterious effects on smaller mammals.The activity of dingoes, foxes, feral cats and bandicoots was assessed from their tracks. Kangaroos and wallabies and possums were counted from the back of a four wheel drive. Traps were used to catch marsupials and native rodents, and surveys of vegetation were carried out.”We found foxes and large herbivores benefit from dingo control, while small-bodied terrestrial mammal species decline in abundance,” says Dr Letnic.”Predation by foxes is one of the most important threats to small native mammals, and grazing by herbivores can reduce their preferred habitats for shelter, leaving them exposed to predators.”The study’s findings in the forested areas are consistent with the effects of dingo removal in desert areas of Australia.”Actively maintaining dingo populations, or restoring them in areas where they have been exterminated, is controversial but could mitigate the impacts of foxes and herbivores,” says Dr Letnic.”Poisoning of dingoes is counter-productive for biodiversity conservation, because it results in increases in fox activity and declines of small ground-dwelling native mammals.”Story Source:The above story is based on materials provided by University of New South Wales. Note: Materials may be edited for content and length.

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Ancient ‘great leap forward’ for life in the open ocean: Cyanobacteria sheds light on how complex life evolved on earth

Plankton in Earth’s oceans received a huge boost when microorganisms capable of creating soluble nitrogen ‘fertilizer’ directly from the atmosphere diversified and spread throughout the open ocean. This event occurred at around 800 million years ago and it changed forever how carbon was cycled in the ocean.It has long been believed that the appearance of complex multicellular life towards the end of the Precambrian (the geologic interval lasting up until 541 million years ago) was facilitated by an increase in oxygen, as revealed in the geological record. However, it has remained a mystery as to why oxygen increased at this particular time and what its relationship was to ‘Snowball Earth’ — the most extreme climatic changes Earth has ever experienced — which were also taking place around then.This new study shows that it could in fact be what was happening to nitrogen at this time that helps solve the mystery.The researchers, led by Dr Patricia Sanchez-Baracaldo of the University of Bristol, used genomic data to reconstruct the relationships between those cyanobacteria whose photosynthesis in the open ocean provided oxygen in quantities sufficient to be fundamental in the development of complex life on Earth.Some of these cyanobacteria were also able to transform atmospheric nitrogen into bioavailable nitrogen in sufficient quantities to contribute to the marine nitrogen cycle, delivering ‘nitrogen fertiliser’ to the ecosystem. Using molecular techniques, the team were able to date when these species first appeared in the geological record to around 800 million years ago.Dr Sanchez-Baracaldo, a Royal Society Dorothy Hodgkin Research Fellow in Bristol’s Schools of Biological and Geographical Sciences said: “We have known that oxygenic photosynthesis — the process by which microbes fix carbon dioxide into carbohydrates, splitting water and releasing oxygen as a by-product — first evolved in freshwater habitats more than 2.3 billion years ago. But it wasn’t until around 800 million years ago that these oxygenating cyanobacteria were able to colonise the vast oceans (two thirds of our planet) and be fertilised by enough bioavailable nitrogen to then produce oxygen — and carbohydrate food — at levels high enough to facilitate the next ‘great leap forward’ towards complex life.”Our study suggests that it may have been the fixing of this nitrogen ‘fertiliser’ in the oceans at this time that played a pivotal role in this key moment in the evolution of life on Earth.”Co-author, Professor Andy Ridgwell said: “The timing of the spread in nitrogen fixers in the open ocean occurs just prior to global glaciations and the appearance of animals. Although further work is required, these evolutionary changes may well have been related to, and perhaps provided a trigger for, the occurrence of extreme glaciation around this time as carbon was now being buried in the sediments on a much larger scale.”Dr Sanchez-Baracaldo added: “It’s very exciting to have been able to use state of the art genetic techniques to help solve an age-old mystery concerning one of the most important and pivotal moments in the evolution of life on Earth. In recent years, genomic data has been helping re-tell the story of the origins of life with increasing clarity and accuracy. It is a privilege to be contributing to our understanding of how microorganisms have contributed to make our planet habitable.”Story Source:The above story is based on materials provided by University of Bristol. Note: Materials may be edited for content and length.

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Guideline: People with irregular heartbeat should take blood thinners to prevent stroke, experts say

An updated guideline from the American Academy of Neurology recommends that people with nonvalvular atrial fibrillation, or irregular heartbeat, take oral anticoagulants, a type of blood thinner pill, to prevent stroke. The guideline is published in the February 25, 2014, print issue of Neurology, the medical journal of the American Academy of Neurology. The World Stroke Organization has endorsed the updated guideline.Taking anticoagulants is especially important for people who have already had a stroke or a transient ischemic attack, which is a threatened stroke.Irregular heartbeat is a major risk factor for stroke. “The World Health Organization has determined that atrial fibrillation is nearing epidemic proportions, affecting 0.5 percent of the population worldwide,” said guideline lead author Antonio Culebras, MD, of SUNY Upstate Medical University in Syracuse, NY, and a Fellow of the American Academy of Neurology.The uneven heart rhythm allows blood to remain in the heart’s upper chambers. The blood can then form clots. These may escape the heart and travel to the brain, causing a stroke. About one in 20 people with untreated atrial fibrillation will likely have a stroke in the next year. Anticoagulants are highly effective in preventing stroke, but they also carry a risk of bleeding. They should be used only under close medical supervision.Several new anticoagulant pills have been developed since the AAN’s last guideline on this topic, which was published in 1998. The current guideline determined that the new anticoagulant pills, such as dabigatran, rivaroxaban and apixaban, are at least as effective, if not more effective than, the established treatment of warfarin and have a lower risk of bleeding in the brain. …

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To hear without being heard: First nonreciprocal acoustic circulator created

A team of researchers at The University of Texas at Austin’s Cockrell School of Engineering has built the first-ever circulator for sound. The team’s experiments successfully prove that the fundamental symmetry with which acoustic waves travel through air between two points in space (“if you can hear, you can also be heard”) can be broken by a compact and simple device.”Using the proposed concept, we were able to create one-way communication for sound traveling through air,” said Andrea Al, who led the project and is an associate professor and David & Doris Lybarger Endowed Faculty Fellow in the Cockrell School’s Department of Electrical and Computer Engineering. “Imagine being able to listen without having to worry about being heard in return.”This successful experiment is described in “Sound Isolation and Giant Linear Nonreciprocity in a Compact Acoustic Circulator,” which will be featured on the cover of Science in the Jan. 31 issue.An electronic circulator, typically used in communication devices and radars, is a nonreciprocal three-port device in which microwaves or radio signals are transmitted from one port to the next in a sequential way. When one of the ports is not used, the circulator acts as an isolator, allowing signals to flow from one port to the other, but not back. The UT Austin team realized the same functionality is true for sound waves traveling in air, which led to the team’s building of a first-of-its-kind three-port acoustic circulator.Romain Fleury, the paper’s first author and a Ph.D. student in Al’s group, said the circulator “is basically a one-way road for sound. The circulator can transmit acoustic waves in one direction but block them in the other, in a linear and distortion-free way.”The scientific knowledge gained from successfully building a nonreciprocal sound circulator may lead to advances in noise control, new acoustic equipment for sonars and sound communication systems, and improved compact components for acoustic imaging and sensing.”More broadly, our paper proves a new physical mechanism to break time-reversal symmetry and subsequently induce nonreciprocal transmission of waves, opening important possibilities beyond applications in acoustics,” Al said. “Using the same concept, it may actually be possible to construct simpler, smaller and cheaper electronic circulators and other electronic components for wireless devices, as well as to create one-way communication channels for light.”This research may eventually allow for an “acoustical version of one-way glass,” said Preston Wilson, acoustics expert and associate professor in the Department of Mechanical Engineering. “It also opens up avenues for very efficient sound isolation and interesting new concepts for active control of sound isolators.”At the core of the team’s sound circulator is a resonant ring cavity loaded with three small computer fans that circulate the airflow at a specific velocity. …

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Scientists discover genetic disease that causes recurrent respiratory infections

Oct. 17, 2013 — Cambridge scientists have discovered a rare genetic disease which predisposes patients to severe respiratory infections and lung damage. Because the scientists also identified how the genetic mutation affects the immune system, they are hopeful that new drugs that are currently undergoing clinical trials to treat leukemia may also be effective in helping individuals with this debilitating disease.For the study, led by the University of Cambridge in collaboration with the Babraham Institute and the MRC Laboratory for Molecular Biology, the researchers first examined genetic information from individuals who suffer from immunodeficiency and are predisposed to infections. From this group, the scientists identified a unique genetic mutation in 17 patients that suffer from severe respiratory infections and rapidly develop lung damage.The researchers, who were primarily funded by the Wellcome Trust, MRC, BBSRC and the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre, found that the mutation increases activity of an enzyme called Phosphoinositide 3-Kinase δ (PI3Kδ). The enzyme is present in immune cells and regulates their function. However, constantly activated PI3Kδ impairs work of these immune cells, preventing them from responding efficiently to infection and providing long-lasting protection. Consequently, patients with this mutation have severe and recurrent infections.”Patients with this mutation have a defect in the immune cells, so their protection from infections is weak and inefficient,” said Sergey Nejentsev, Wellcome Trust Senior Research Fellow from the University of Cambridge who led the research. “We called this newly identified disease Activated PI3K- δ Syndrome (APDS) after the enzyme in the immune system that is affected by the genetic mutation.”The researchers believe that it may be possible to treat APDS in future. There are currently drugs in clinical trials for leukemia that were designed specifically to inhibit the PI3Kδ enzyme. The researchers have already shown that these drugs reduce activity of the mutant protein.Alison Condliffe, joint senior author on the paper from the University of Cambridge, said: “We are very excited by the prospect of using these drugs to help patients with APDS. …

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Breakthrough in sensing at the nanoscale

Sep. 1, 2013 — Researchers have made a breakthrough discovery in identifying the world’s most sensitive nanoparticle and measuring it from a distance using light. These super-bright, photostable and background-free nanocrystals enable a new approach to highly advanced sensing technologies using optical fibres.This discovery, by a team of researchers from Macquarie University, the University of Adelaide, and Peking University, opens the way for rapid localisation and measurement of cells within a living environment at the nanoscale, such as the changes to a single living cell in the human body in response to chemical signals.Published in Nature Nanotechnology today, the research outlines a new approach to advanced sensing that has been facilitated by bringing together a specific form of nanocrystal, or “SuperDot™” with a special kind of optical fibre that enables light to interact with tiny (nanoscale) volumes of liquid.”Up until now, measuring a single nanoparticle would have required placing it inside a very bulky and expensive microscope,” says Professor Tanya Monro, Director of the University of Adelaide’s Institute for Photonics and Advanced Sensing (IPAS) and ARC Australian Laureate Fellow. “For the first time, we’ve been able to detect a single nanoparticle at one end of an optical fibre from the other end. That opens up all sorts of possibilities in sensing.””Using optical fibres we can get to many places such as inside the living human brain, next to a developing embryo, or within an artery ‒ locations that are inaccessible to conventional measurement tools.”This advance ultimately paves the way to breakthroughs in medical treatment. For example, measuring a cell’s reaction in real time to a cancer drug means doctors could tell at the time treatment is being delivered whether or not a person is responding to the therapy.”The performance of sensing at single molecular level had previously been limited by both insufficient signal strength and interference from background noise. The special optical fibre engineered at IPAS also proved useful in understanding the properties of nanoparticles.”Material scientists have faced a huge challenge in increasing the brightness of nanocrystals,” says Dr. Jin, ARC Fellow at Macquarie University’s Advanced Cytometry Laboratories. “Using these optical fibres, however, we have been given unprecedented insight into the light emissions. Now, thousands of emitters can be incorporated into a single SuperDot™ — creating a far brighter, and more easily detectable nanocrystal.”Under infrared illumination, these SuperDots™ selectively produce bright blue, red and infrared light, with a staggering thousand times more sensitivity than existing materials. …

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Mosquitoes smell you better at night

Aug. 30, 2013 — In work published this week in Nature: Scientific Reports, a team of researchers from the University of Notre Dame’s Eck Institute for Global Health, led by Associate Professor Giles Duffield and Assistant Professor Zain Syed of the Department of Biological Sciences, revealed that the major malaria vector in Africa, the Anopheles gambiae mosquito, is able to smell major human host odorants better at night.The study reports an integrative approach to examine the mosquito’s ability to smell across the 24-hour day and involved proteomic, sensory physiological, and behavioral techniques. The researchers examined the role for a major chemosensory family of mosquito proteins, odorant-binding proteins (OBPs), in the daily regulation of olfactory sensitivities in the malarial mosquito. It is thought that OBPs in the insect antennae and mouth parts function to concentrate odorant molecules and assist in their transport to the actual olfactory receptors, thereby allowing for odorant detection. The team revealed daily rhythmic protein abundance of OBPs, having higher concentrations in the mosquito’s sensory organs at night than during the day. This discovery could change the way we look at protecting ourselves from these disease-carrying pests.The team also included Matthew M. Champion, Eck Institute for Global Health Research Assistant Professor in the Department of Chemistry and Biochemistry, who specializes in proteomics.This study utilized mass spectrometry to quantify protein abundance in mosquito sensory organs, and electroantennograms to determine the response induced by host odorants at different times of the day. The coincident times of peak protein abundance, olfactory sensitivity and biting behavior reflect the extraordinarily fine-tuned control of mosquito physiology. Olfactory protein abundance and olfactory sensitivity are high when needed (at night) and low when not required (daytime).Samuel Rund, a doctoral candidate in the laboratory of Duffield and a former Eck Institute for Global Health Fellow, and Nicolle Bonar, a visiting undergraduate student from Queens University of Ontario, Canada, were the lead authors on this research. The Notre Dame team also included then-undergraduate student John Ghazi, Class of 2012; undergraduate Cameron Houk, Class of ’14; and graduate student Matthew Leming.Rund noted, “This was an exciting opportunity to bring many people and techniques together to make some really fascinating findings on the mosquito’s ability to smell humans, its host. …

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Higher intake of fruits and vegetables may reduce the risk of bladder cancer in women

Aug. 23, 2013 — University of Hawaii Cancer Center Researcher Song-Yi Park, PhD, along with her colleagues, recently discovered that a greater consumption of fruits and vegetables may lower the risk of invasive bladder cancer in women.Share This:The investigation was conducted as part of the Multiethnic Cohort (MEC) Study, established in 1993 to assess the relationships among dietary, lifestyle, genetic factors, and cancer risk. Park and her fellow researcher’s analyzed data collected from 185,885 older adults over a period of 12.5 years, of which 581 invasive bladder cancer cases were diagnosed (152 women and 429 men).After adjusting for variables related to cancer risk (age, etc.) the researchers found that women who consumed the most fruits and vegetables had the lowest bladder cancer risk. For instance, women consuming the most yellow-orange vegetables were 52% less likely to have bladder cancer than women consuming the least yellow-orange vegetables. The data also suggested that women with the highest intake of vitamins A, C, and E had the lowest risk of bladder cancer. No associations between fruit and vegetable intake and invasive bladder cancer were found in men.”Our study supports the fruit and vegetable recommendation for cancer prevention, said Park. “However, further investigation is needed to understand and explain why the reduced cancer risk with higher consumption of fruits and vegetables was confined to only women.”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 University of Hawaii Cancer Center, via EurekAlert!, a service of AAAS. Note: Materials may be edited for content and length. For further information, please contact the source cited above. Journal Reference:S.-Y. …

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Preschoolers inability to estimate quantity relates to later math difficulty

Aug. 14, 2013 — Preschool children who showed less ability to estimate the number of objects in a group were 2.4 times more likely to have a later mathematical learning disability than other young people, according to a team of University of Missouri psychologists. Parents may be able to help their children develop their skills at approximating group sizes by emphasizing numerals while interacting with young children.”Lacking skill at estimating group size may impede a child’s ability to learn the concept of how numerals symbolize quantities and how those quantities relate to each other,” said study co-author David Geary, professor of psychological sciences at MU. “Not understanding the values numbers symbolize then leads to difficulties in math and problems in school, which our previous studies suggest may be related to later difficulties with employment.”Geary said that parents may be able to improve a child’s innate skill at approximating group size and suggested that caregivers draw children’s attention to quantities in everyday situations. For example, after a preschool-aged child completes a series of tasks, a parent can ask the youth how many tasks they completed.”Talking to children about how the world can be represented in numbers may help young people develop the ability to estimate the size of a group, which may prepare them for later mathematics education” said co-author Kristy vanMarle, assistant professor of psychological science at MU. “Asking them ‘how many’ whenever they encounter a group of objects or images can help them understand that the world can be understood in terms of numbers.”However, the inability to approximate group size was not the only factor related to later math problems. The MU team also found that preschoolers who lagged behind others in their understanding of the symbolic value of numerals and other related concepts were 3.6 to 4.5 times more likely to show mathematical learning difficulties, which corroborates earlier research by Geary, and extends it to a much younger age.Doctoral student Felicia W. Chu was the lead author of the study, “Quantitative deficits of preschool children at risk for mathematical learning disability,” which was published in the journal Frontiers in Psychology.”One major reason I came to the University of Missouri was the psychology department’s strong reputation for studying children’s mathematical education,” said Chu.Geary is Curators’ Professor and a Thomas Jefferson Fellow in the Department of Psychological Sciences in MU’s College of Arts and Science. vanMarle is the director of MU’s Developmental Cognition Lab.

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Baby corals pass the acid test

Aug. 13, 2013 — Corals can survive the early stages of their development even under the tough conditions that rising carbon emissions will impose on them says a new study from the ARC Centre of Excellence for Coral Reef Studies.Globally, ocean acidification due to the burning of fossil fuels remains a major concern and scientists say it could have severe consequences for the health of adult corals, however, the evidence for negative effects on the early life stages of corals is less clear cut.Dr Andrew Baird, Principal Research Fellow at the ARC Centre of Excellence for Coral Reef Studies and James Cook University, was part of the research team and explains their findings.”The prevailing view is that ocean acidification will act like a toxin to corals, but we were unconvinced by results from previous work on young corals and ocean acidification so we tested critical early stages of development in several coral species at several different acid (or ‘pH’) concentrations of seawater.”Our results showed no clear response to increasing ocean acidification in any of the stages, or for any of the coral species,” says Dr Baird. “In fact, in only one of nine experiments did we get the response expected if CO2 was acting like a toxin. More often than not we found no effect.”By bubbling CO2 through seawater the research team was able to simulate future levels of ocean acidification expected to result from rising human carbon emissions. They tested the success of embryo development, the survival of coral larvae and finally their success in settling on coral reefs.Although their results suggest that ocean acidification may not affect the early stages of coral development, the team warn that this does not mean acidification is not a threat to corals.”Undoubtedly, as the oceans become more acidic adult corals are going to struggle to build their skeletons, which might hinder their ability to grow, reproduce and compete for space on reefs. We also have to remember that the oceans are getting warmer, so corals will be dealing with higher temperatures, as well as higher acidity.”Fortunately, before corals settle on to reefs they don’t need to grow a skeleton, which might explain why they are apparently unaffected in by higher levels of ocean acidification,” says Dr Chia-Miin Chua, the lead author of the study.”This message is reinforced when we look at the early life stages of creatures that do need a larval skeleton, such as sea urchins and oysters. In these cases we see early life stage development slowing down as acidity increases.”However the study does not discount the possibility that coral larvae may suffer other ill-effects from increasing ocean acidification, for example, their swimming speeds may slow down, but because coral larvae typically settle on the reef two or three weeks after birth it is unlikely that these effects will have a major impact on the survival or settlement of coral larvae.Dr Baird says that while the long-term outlook for corals may be gloomy, this research highlights the fact that not all life stages of corals will be equally affected.

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Regulating electron ‘spin’ may be key to making organic solar cells competitive

Aug. 7, 2013 — Organic solar cells, a new class of solar cell that mimics the natural process of plant photosynthesis, could revolutionise renewable energy — but currently lack the efficiency to compete with the more costly commercial silicon cells.At the moment, organic solar cells can achieve as much as 12 per cent efficiency in turning light into electricity, compared with 20 to 25 per cent for silicon-based cells.Now, researchers have discovered that manipulating the ‘spin’ of electrons in these solar cells dramatically improves their performance, providing a vital breakthrough in the pursuit of cheap, high performing solar power technologies.The study, by researchers from the Universities of Cambridge and Washington, is published today in the journal Nature, and comes just days after scientists called on governments around the world to focus on solar energy with the same drive that put a man on the moon, calling for a “new Apollo mission to harness the sun’s power.”Organic solar cells replicate photosynthesis using large, carbon-based molecules to harvest sunlight instead of the inorganic semiconductors used in commercial, silicon-based solar cells. These organic cells can be very thin, light and highly flexible, as well as printed from inks similar to newspapers — allowing for much faster and cheaper production processes than current solar cells.But consistency has been a major issue. Scientists have, until now, struggled to understand why some of the molecules worked unexpectedly well, while others perform indifferently.Researchers from Cambridge’s Cavendish Laboratory developed sensitive laser-based techniques to track the motion and interaction of electrons in these cells. To their surprise, the team found that the performance differences between materials could be attributed to the quantum property of ‘spin’.’Spin’ is a property of particles related to their angular momentum, with electrons coming in two flavours, ‘spin-up’ or ‘spin-down’. Electrons in solar cells can be lost through a process called ‘recombination’, where electrons lose their energy — or “excitation” state — and fall back into an empty state known as the “hole.”Researchers found that by arranging the electrons ‘spin’ in a specific way, they can block the energy collapse from ‘recombination’ and increase current from the cell.”This discovery is very exciting, as we can now harness spin physics to improve solar cells, something we had previously not thought possible. We should see new materials and solar cells that make use of this very soon” said Dr. Akshay Rao, a Research Fellow at the Cavendish Laboratory and Corpus Christi College, Cambridge, who lead the study with colleagues Philip Chow and Dr. Simon Gélinas.The Cambridge team believe that design concepts coming out of this work could help to close the gap between organic and silicon solar cells, bringing the large-scale deployment of solar cells closer to reality. In addition, some of these design concepts could also be applied to Organic Light Emitting diodes, a new and rapidly growing display technology, allowing for more efficient displays in cell phones and TVs.

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New and remarkable details of the sun

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

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Skipping breakfast may increase coronary heart disease risk

July 22, 2013 — A large 16-year study finds men who reported that they skipped breakfast had higher risk of heart attack or death from coronary heart disease. The timing of meals, whether it’s missing a meal in the morning or eating a meal very late at night, may cause adverse metabolic effects that lead to coronary heart disease. Even after accounting for modest differences in diet, physical activity, smoking and other lifestyle factors, the association between skipping breakfast (or eating very late at night) and coronary heart disease persisted.Here’s more evidence why breakfast may be the most important meal of the day: Men who reported that they regularly skipped breakfast had a higher risk of a heart attack or fatal coronary heart disease in a study reported in the American Heart Association journal Circulation.Researchers analyzed food frequency questionnaire data and tracked health outcomes for 16 years (1992-2008) on 26,902 male health professionals ages 45-82. They found:Men who reported they skipped breakfast had a 27 percent higher risk of heart attack or death from coronary heart disease than those who reported they didn’t. The men who reported not eating breakfast were younger than those who did, and were more likely to be smokers, employed full time, unmarried, less physically active and drank more alcohol. Men who reported eating late at night (eating after going to bed) had a 55 percent higher coronary heart disease risk than those who didn’t. But researchers were less convinced this was a major public health concern because few men in the study reported this behavior. During the study, 1,572 of the men had first-time cardiac events. “Skipping breakfast may lead to one or more risk factors, including obesity, high blood pressure, high cholesterol and diabetes, which may in turn lead to a heart attack over time,” said Leah E. Cahill, Ph.D., study lead author and Postdoctoral Research Fellow in the Department of Nutrition at Harvard School of Public Health in Boston, Mass.”Our study group has spent decades studying the health effects of diet quality and composition, and now this new data also suggests overall dietary habits can be important to lower risk of coronary heart disease,” said Eric Rimm, Sc.D., senior author and Associate Professor of Epidemiology and Nutrition, Harvard School of Public Health and Associate Professor of Medicine at the Harvard Medical School.Men who reported eating breakfast ate on average one more time per day than those who skipped breakfast, implying that those who abstained from breakfast were not eating additional make-up meals later in the day. …

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Lionfish expedition: Down deep is where the big, scary ones live

July 11, 2013 — Last month, the first expedition to use a deep-diving submersible to study the Atlantic Ocean lionfish invasion found something very disturbing — at 300 feet deep, there were still significant populations of these predatory fish, and they were big.Big fish in many species can reproduce much more efficiently than their younger, smaller counterparts, and lionfish are known to travel considerable distances and move to various depths. This raises significant new concerns in the effort to control this invasive species that is devastating native fish populations on the Atlantic Coast and in the Caribbean Sea.”We expected some populations of lionfish at that depth, but their numbers and size were a surprise,” said Stephanie Green, the David H. Smith Conservation Research Fellow in the College of Science at Oregon State University, who participated in the dives. OSU has been one of the early leaders in the study of the lionfish invasion.”This was kind of an ‘Ah hah!’ moment,” she said. “It was immediately clear that this is a new frontier in the lionfish crisis, and that something is going to have to be done about it. Seeing it up-close really brought home the nature of the problem.”OSU participated in this expedition with researchers from a number of other universities, in work supported by Nova Southeastern University, the Guy Harvey Foundation, NOAA, and other agencies. The five-person submersible “Antipodes” was provided by OceanGate, Inc., and it dove about 300 feet deep off the coast of Ft. Lauderdale, Fla., near the “Bill Boyd” cargo ship that was intentionally sunk there in 1986 to create an artificial reef for marine life.That ship has, in fact, attracted a great deal of marine life, and now, a great number of lionfish. And for that species, they are growing to an unusually large size — as much as 16 inches.Lionfish are a predatory fish that’s native to the Pacific Ocean and were accidentally introduced to Atlantic Ocean waters in the early 1990s, and there became a voracious predator with no natural controls on its population. An OSU study in 2008 showed that lionfish in the Atlantic have been known to reduce native fish populations by up to 80 percent.Eradication appears impossible, and they threaten everything from coral reef ecosystems to local economies that are based on fishing and tourism.Whatever is keeping them in check in the Pacific — and researchers around the world are trying to find out what that is — is missing here. …

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Changes in cell shape may lead to metastasis, not the other way around

June 21, 2013 — A crucial step toward skin cancer may be changes in the genes that control cell shape, report a team of scientists from The Methodist Hospital Research Institute, the Institute of Cancer Research, London, and Harvard Medical School in an upcoming issue of Nature Cell Biology (now online).Using automated high content screening and sophisticated computational modeling, the researchers’ screening and analysis of tens of millions of genetically manipulated cells helped them identify more than a dozen genes that influence cell shape. Their work could lead to a better understanding of how cells become metastatic and, eventually, pinpoint new gene therapy targets for cancer treatment.”We found that by altering the way the cells are grown to better mimic conditions in a living organism, gene expression could have a profound impact on cell shape,” said Zheng Yin, the paper’s lead author and a postdoctoral fellow at the Department of Systems Medicine and Bioengineering of The Methodist Hospital Research Institute (TMHRI). “This matters because many cancer biologists believe metastasis depends in part on the ability of cells to take on different shapes to escape their confines and spread to healthy tissue. We developed a method of identifying and analyzing the shapes of fruit fly cells, then validated and expanded the discoveries in mammal cancer cells..”The scientists began their study in fruit fly immune cells called hemocytes. Under normal conditions, each hemocyte was found to take on just one of five distinct shapes about 98 percent of the time. In contrast to conventional wisdom, other shapes and “intermediate” forms were rare, suggesting genes that control cell shape behave more like light switches than teakettles coming to a slow boil. Genetic manipulation of these cells in a lab setting supported that view as well.Next the group examined human and mouse melanoma cells, which also take on a variety of forms. The researchers identified seven genes that cause cells to take on an especially rounded form, or else an elongated form. One of these genes, PTEN, had a particularly strong impact. When turned off, virtually all cells became elongated or large and rounded, two shapes that can help cancerous cells escape confinement, travel blood vessels, and infiltrate healthy tissues. …

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Simple and inexpensive process to make a material for CO2 adsorption

June 19, 2013 — Researchers from Ulsan National Institute of Science and Technology (UNIST), S. Korea, developed a novel, simple method to synthesize hierarchically nanoporous frameworks of nanocrystalline metal oxides such as magnesia and ceria by the thermal conversion of well-designed metal-organic frameworks (MOFs).The novel material developed by the UNIST research team has exceptionally high CO2 adsorption capacity which could pave the way to save Earth from CO2 pollution.Nanoporous materials consist of organic or inorganic frameworks with a regular, porous structure. Because of their uniform pore sizes they have the property of letting only certain substances pass through, while blocking others. Nanoporous metal oxide materials are ubiquitous in materials science because of their numerous potential applications in various areas, including adsorption, catalysis, energy conversion and storage, optoelectronics, and drug delivery. While synthetic strategies for the preparation of siliceous nanoporous materials are well-established, non-siliceous metal oxide-based nanoporous materials still present challenges.A description of the new research was published (Web) on May 7 in the Journal of the American Chemical Society.Leading the research team is married couple Hoi Ri Moon and Sang Hoon Joo, both assistant professors at UNIST, who contributed to synthesizing nanoporous metal oxides and characterizing nanoporous materials respectively. Fellow authors include Tae Kyung Kim, Kyung Joo Lee, Jae Yeong Cheon and Jae Hwa Lee from UNIST.The UNIST research team used MOFs based on aliphatic carboxylate ligands which are thermally less stable and much more labile than aromatic ligands. Specifically, the aliphatic ligand is adipic acid, which is a precursor for the production of nylon, and thus very important from an industrial perspective and low in price. During the thermolysis of a crystalline, aliphatic carboxylate ligand-based MOF (aph-MOF), the ligands were transformed into organic moieties via chemical decomposition, and were confined as vesicles in the solids.The organic vesicles acted as self-generated porogens, which later were converted into nanopores; they also prevented aggregation of the metal oxide nanocrystals. Finally, upon thermolysis at higher temperature, the confined organic moieties evaporated, generating highly porous nanostructures comprising nanocrystalline metal oxides. The control of the retention time and the evaporation rate of the organic moieties in the host solid were critical for the successful formation of nanoporous metal oxides with nanocrystalline frameworks. …

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Mice in a ‘Big Brother’ setup develop social structures

June 17, 2013 — How does a social animal — mouse or human — gain dominance over his or her fellow creatures? A unique experiment conducted by Dr. Tali Kimchi and her team in the Weizmann Institute’s Neurobiology Department provides some unusual insight into the social behavior that enables a social hierarchy, complete with a head honcho, to form.Kimchi and her research team, Aharon Weissbrod, Genady Wasserman and Alex Shapiro, together with Dr. Ofer Feinerman of the Institute’s Physics of Complex Systems Department, developed a system that enabled them to observe a large group of animals living together in semi-natural conditions. This setup was a sort of mouse version of the television show Big Brother. Different strains of mice were placed in the “house” — a four-meter-square pen — and allowed to go about their lives with no intervention from the human team. To automatically track the mice day and night, each mouse was implanted with an ID chip similar to those used in pet cats and dogs, and video cameras were placed strategically around the area with infrared lighting that enabled nighttime filming. With the combined chip reporting and continuous video footage, the system could automatically keep tabs on each individual mouse, knowing its precise location down to the half centimeter, in measurements that were recorded thirty times a second for days and sometimes even months on end.Because the information they obtained was so precise, the team was able to identify dozens of individual behaviors — eating, drinking, running, sleeping, hiding, etc. — as well as social behaviors — seeking out specific companions for activities or rest, avoiding certain individuals, attacking others, and more. The researchers found that it was possible to isolate and identify typical behaviors of individuals, pairs and groups. …

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Body clocks linked to osteoarthritis

June 11, 2013 — Scheduled exercise, regular meals and the periodic warming and cooling of joints could be used to relieve the symptoms of osteoarthritis according to scientists at The University of Manchester. Their research may also help explain why older people are more prone to developing this common joint disorder.The team in the Faculty of Life Sciences has established for the first time that cartilage cells have a functioning body clock that switches on and off genes controlling tissue function. The rhythm of the cartilage clock perhaps goes some way to explain why osteoarthritis sufferers find the symptoms of the disease worse at certain times of the day.When Dr Qing-Jun Meng and his team studied cartilage tissue in older mice they found that the tissue’s body clock was 40% weaker than in younger mice. This suggested that clock deterioration could contribute to an increased risk of developing osteoarthritis in later life. The researchers then looked at cartilage cells affected by damage similar to osteoarthritis and found that components of the body clock are altered during the early stages of the disease.Following these discoveries the researchers tested what would happen to cartilage tissue in mice and human cartilage cells if they imposed an artificial rhythm mimicking daily changes of body temperature. By raising the temperature by two degrees at 12 hour intervals they found that after three applications the body clock in the cells had been reset and was working in a more robust state. This change lasted for between five and seven days even after the temperature cycles were removed. Further study may show the change continues for longer.Dr Meng says: “By imposing a rhythm to boost the internal rhythm in cartilage, our data suggests the aged cartilage clock might be re-tuned. This could be done using systemic approaches such as scheduled exercise, restricted meal times or by targeting the joint itself with scheduled warming and cooling. We believe imposing a rhythm could have a significant impact on the future management of joint diseases and with further study it could relieve sufferers’ symptoms.”This ground breaking research also suggests that taking drug treatments for joint diseases according to the cartilage clock time could increase their effectiveness, which would allow a lower dosage and consequently reduce side effects.Dr Meng, a Medical Research Council (MRC) Fellow, has been studying body clocks for a number of years: “Mounting evidence suggests that disruption to body clocks by changes like shift work or jet lag contribute to a number of conditions such as obesity, cardiovascular diseases, cancer and mood disorders. …

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