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News Article | February 15, 2017
Site: www.eurekalert.org

The development of super resolution microscopy has revolutionised how scientists view and understand the inner workings of the cell. Just as advances in satellite camera technology gave rise to highly detailed maps of the world, so too has super-resolution microscopy allowed researchers to build detailed maps of individual cells. Such is the detail, that not only is the location of individual protein-based machines achievable, but these machines can be broken down into their parts, and the position and orientation of these parts, mapped out as well. In the human body, cells rarely function in isolation. Instead they exist as part of multicellular communities that make up tissues and organs. To ensure the tissue functions correctly, individual cells must remain in physical contact with their surrounding cells. When cells are unable to maintain this contact, devastating diseases may arise, cancer being one of the most dreaded examples. Cell-cell adhesion sites are found at specific regions of the cell periphery. Although many of the protein parts that make up these adhesion sites were known, scientists had yet to determine how each part fit together to make the overall machine. This was because the building blocks of these machines were both far too small for traditional light microscopes, and far too diverse for electron microscopes. One of the main protein parts in these machines are the 'cadherin' proteins. The cadherin of one cell extends outside the cell, and interact with cadherin of another cell. On the inside of the cell, cadherin binds to 'adaptor' proteins, which essentially connect the cadherin to a network of protein filaments known as the cytoskeleton. By forging these robust links, cadherin adhesions not only connect neighbouring cells but allow cells to coordinate their movements, maintain tissue integrity, and relay a myriad of signals important for proper tissue functions. With super-resolution microscopy at their disposal, an international research team led by Assistant Professor Pakorn (Tony) Kanchanawong from the Mechanobiology Institute, Singapore (MBI) at the National University of Singapore (NUS) and the Department of Biomedical Engineering at NUS, as well as Dr Cristina Bertocchi, Research Fellow at MBI, has revealed, for the first time, how the cadherin-based cell-cell contacts are organised. At the heart of the study is a 'map' of how the parts are pieced together into a sophisticated nanoscale cell-cell adhesion machine. The study was published online in Nature Cell Biology in December 2016. Here, the researchers 'mapped' the position and orientation of the protein building blocks of cadherin adhesions. They noted a striking degree of compartmentalisation in the organisation of the protein machinery where components were arranged into multiple layers. The cadherin and the cytoskeleton compartments appeared to be separated by an 'interface layer', which contains vinculin, a stretchable protein which has long been implicated in the cell's ability to sense mechanical force. In this case, Dr Bertocchi observed that vinculin could undergo a dramatic shape-shifting transformation, whereby it would switch from a compact shape to a highly elongated form. This elongated form was sufficient to stretch over a distance of 30 nanometres or more, which was the same distance that cadherin was separated from the cytoskeleton. In a nutshell, vinculin could serve as a bridge to link between the cadherin and actin layers. Further investigation of this structure highlighted that the shape of vinculin (stretched or compact) was determined by both mechanical tension and biochemical signal inputs. Therefore, the ability of vinculin to selectively engage with a highly dynamic actin cytoskeleton highlights vinculin's role in fine-tuning the mechanical properties of cell-cell contacts in response to varying inputs from the extracellular environment. The ability to observe, under a microscope, molecular machines such as the cadherin based cell-cell adhesion highlights the power of super resolution microscopy. In this case, the protein parts that make up the cell-cell adhesion have been mapped out, allowing researchers to better understand how cell-cell contacts are formed, maintained, regulated and re


News Article | March 2, 2017
Site: www.eurekalert.org

The Ecological Society of America (ESA) will present the 2017 awards recognizing outstanding contributions to ecology in new discoveries, teaching, sustainability, diversity, and lifelong commitment to the profession during the Society's Annual Meeting in Portland, Ore. The awards ceremony will take place during the Scientific Plenary on Monday, August 7, at 8 AM in the Oregon Ballroom, Oregon Convention Center. Learn more about ESA awards on our home website. The Eminent Ecologist Award honors a senior ecologist for an outstanding body of ecological work or sustained ecological contributions of extraordinary merit. Soil ecologist Diana Wall, the founding director of the Colorado State University's School of Global Environmental Sustainability, is world-renowned for uncovering the importance of below-ground processes. Best known for her outstanding quarter century of research in the McMurdo Dry Valleys in Antarctica, one of the more challenging environments of the planet. Her research has revealed fundamental soil processes from deserts and forests to grasslands and agricultural ecosystems to New York City's Central Park. Dr. Wall's extensive collaborative work seeks to understand how the living component of soil contributes to ecosystem processes and human wellbeing--and to in turn uncover how humans impact soils, from local to global scales. In landmark studies, she revealed the key role of nematodes and other tiny animals as drivers of decomposition rates and carbon cycling. The biodiversity in soils, she found, influences ecosystem functioning and resilience to human disturbance, including climate change. She demonstrated that the biodiversity belowground can at times be decoupled from biodiversity aboveground. Her focus on nematodes in soils in very harsh environments, from the cold, dry Antarctic to hot, dry deserts, opened up a perspective on how life copes with extreme environments. She has a laudable record of publishing excellent papers in top-ranked scientific journals. Dr. Wall has played a vital role as an ecological leader, chairing numerous national and international committees and working groups and serving as president of the Ecological Society of America in 1999. She is a Fellow of ESA, the American Association for the Advancement of Science, and the Society of Nematologists. In 2013, she received the Tyler Prize for Environmental Achievement for her outspoken efforts as an ambassador for the environmental and economic importance of soils and ecology. Currently, she is scientific chair of the Global Soil Biodiversity Initiative, which works to advance soil biodiversity for use in policy and management of terrestrial ecosystems. Dr. Wall is well-respected in her role as mentor of young scientists, over several generations, and as a communicator of science outside the usual academic arenas. Odum Award recipients demonstrate their ability to relate basic ecological principles to human affairs through teaching, outreach, and mentoring activities.? Kathleen Weathers is a senior scientist and the G.Evelyn Hutchinson chair of ecology at the Cary Institute of Ecosystem Studies, where she focuses on freshwater ecosystems. For more than a decade, she has been dedicated to advancing bottom-up network science, creating training opportunities for graduate students and tools for citizen science engagement. Her efforts strive to equip the next generation of ecologists and managers with the skills needed to protect freshwater resources. Dr Weathers played a guiding role in the formation of the Global Lake Ecological Observatory Network (GLEON), and currently acts as co-chair. A part of this international grassroots collaboration she helped develop Lake Observer, a crowd-sourcing App that streamlines the way that researchers and citizen scientists record water quality observations in lakes, rivers, and streams. Dr. Weathers has made it a priority to mentor students and early-career scientists participating in GLEON, with an eye toward diversity, inclusion, and instruction. She helped empower GLEON's student association, which contributes meaningfully to governance and training within the broader network. She also spearheaded the development of the GLEON Fellows Program, a two-year graduate immersion in data analysis, international collaboration, effective communication, and team science. The GLEON Fellows Program has emerged as a model for training initiatives in macrosystem ecology, and will affect the ecological community positively for decades to come, as participants carry their training forward to other institutions and endeavors. The Distinguished Service Citation recognizes long and distinguished volunteer service to ESA, the scientific community, and the larger purpose of ecology in the public welfare. Debra Peters is the founding editor-in-chief of ESA's newest journal, Ecosphere, created in 2010 to offer a rapid path to publication for research reports from across the spectrum of ecological science, including interdisciplinary studies that may have had difficulty finding a home within the scope of the existing ESA family of journals. In her hands the online-only, open-access journal has claimed a successful niche in the ecological publications landscape, expanding to publish over 400 manuscripts in 2016. Dr. Peters, an ecologist for the United States Department of Agriculture Agricultural Research service's (USDA-ARS) Jornada Experimental Range and lead principal investigator for the Jornada Basin Long Term Ecological Research program in Las Cruces, New Mexico, has served on the editorial boards of ESA's journals Ecological Applications, Ecology and Ecological Monographs. She chaired the society's Rangeland Section, was a founding member and chair of the Southwest Chapter, and has served as member-at-large on the Governing Board. As program chair for the 98th Annual Meeting of the society, she inaugurated the wildly popular Ignite talks, which give speakers the opportunity to present conceptual talks that do not fit into the standard research presentation format. Dr. Peters has greatly contributed to the broader research enterprise as senior advisor to the chief scientist at the USDA, and as a member of the National Ecological Observatory Network's (NEON) Board of Directors. She has provided this quite amazing array of services in support of the society and her profession while maintaining an outstanding level of research productivity and scientific leadership in landscape-level, cross-scale ecosystem ecology. Many of her more than 100 research publication have been cited more than 100 times. Her fine record of research led to her election as a Fellow of ESA and the American Association for the Advancement of Science. In all respects, Debra Peters exemplifies distinguished service to the ESA, and to science. ESA's Commitment to Human Diversity in Ecology award recognizes long-standing contributions of an individual towards increasing the diversity of future ecologists through mentoring, teaching, or outreach. Gillian Bowser, research scientist in Colorado State University's Natural Resource Ecology Laboratory, is honored for her joyful and successful recruitment and retention of under-represented students to the study of ecology, to public service in support of the natural world, and to empowerment of women and minorities worldwide. The Cooper Award honors the authors of an outstanding publication in the field of geobotany, physiographic ecology, plant succession or the distribution of plants along environmental gradients. William S. Cooper was a pioneer of physiographic ecology and geobotany, with a particular interest in the influence of historical factors, such as glaciations and climate history, on the pattern of contemporary plant communities across landforms. University of Waterloo, Ontario professor Andrew Trant and colleagues at the University of Victoria and the Hakai Institute in British Columbia revealed a previously unappreciated historical influence on forest productivity: long-term residence of First Nations people. Counter to a more familiar story of damage to ecosystems inflicted by people and their intensive use of resources, the activities of native people on the Central Coast of British Columbia enhanced the fertility of the soil around habitation sites, leading to greater productivity of the dominant tree species, the economically and culturally valuable western redcedar (Thuja plicata Donn ex D. Don). Through a combination of airborne remote sensing and on-the-ground field work, the authors showed that forest height, width, canopy cover, and greenness increased on and near shell middens. They presented the first documentation of influence on forest productivity by the daily life activities of traditional human communities. The Mercer Award recognizes an outstanding and recently-published ecological research paper by young scientists. Biological invasions, and migrations of native species in response to climate change, are pressing areas of interest in this time of global change. Fragmentation of the landscape by natural and human-made barriers slows the velocity of spread, but it is not known how patchy habitat quality might influence the potential for evolution to accelerate invasions. Jennifer Williams, an assistant professor at the University of British Columbia, and colleagues implemented a creative experimental design using the model plant species Arabidopsis thaliana that allowed them to disentangle ecological and evolutionary dynamics during population expansion. Some plant populations were allowed to evolve, while others were continually reset to their original genetic composition. The authors convincingly demonstrate that rapid evolution can influence the speed at which populations spread, especially in fragmented landscapes. The Sustainability Science Award recognizes the authors of the scholarly work that makes the greatest contribution to the emerging science of ecosystem and regional sustainability through the integration of ecological and social sciences. Sustainability challenges like air pollution, biodiversity loss, climate change, energy and food security, disease spread, species invasion, and water shortages and pollution are often studied, and managed, separately, although they the problems they present are interconnected. Jianguo Liu and colleagues provide a framework for addressing global sustainability challenges from a coupled human and natural systems approach that incorporates both socioeconomic and environmental factors. They review several recent papers that have quantified at times conflicting efforts to provide ecosystem services, when these efforts are examined in a global perspective. The authors argue for the need to quantify spillover systems and feedbacks and to integrate analyses over multiple spatial and temporal scales. This will likely require the development of new analytical frameworks both to understand the social ecological mechanisms involved and to inform management and policy decisions for global sustainability. The Innovation in Sustainability Science Award recognizes the authors of a peer-reviewed paper published in the past five years exemplifying leading-edge work on solution pathways to sustainability challenges. One of the biggest challenges facing development of effective policy to address sustainability issues is that the concepts and vocabulary used by scientists to define and promote sustainability rarely translate into effective policy, because they do not include measures of success. This challenge is particularly apparent in the concept of stability and resilience, terms which are frequently used in policy statements and have long been the subject of empirical and theoretical research in ecology, but for which there are no easily defined and quantified metrics. Ian Donohue and colleagues argue that much of the fault for this disconnect lies with the academic community. They summarize and analyze a number of examples to support their claim that ecologists have taken a one-dimensional approach to quantifying stability and disturbance when these are actually multi-dimensional processes. They argue that this has led to confused communication of the nature of stability, which contributes to the lack of adoption of clear policies. They propose three areas where future research is needed and make clear recommendations for better integrating the multidimensional nature of stability into research, policy and actions that should become a priority for all involved in sustainability science. The Whittaker Award recognizes an ecologist with an earned doctorate and an outstanding record of contributions in ecology who is not a U.S. citizen and who resides outside the United States. Petr Pyšek, the chair of the Department of Invasion Ecology at the Academy of Sciences of the Czech Republic, is honored for his pioneering and insightful work in invasion ecology. Dr. Pyšek is editor-in-chief of Preslia (Journal of the Czech Botanical Society) and serves on the editorial boards of Biological Invasions, Diversity and Distributions, Folia Geobotanica, and Perspectives on Plant Ecology, Evolution and Systematics. The Shreve award supplies $1,000-2,000 to support ecological research by graduate or undergraduate student members of ESA in the hot deserts of North America (Sonora, Mohave, Chihuahua, and Vizcaino). Daniel Winkler, a PhD student with Travis Huxman at University of California Irvine, studies the invasion of Sahara mustard (Brassica tournefortii) in the Mojave, Sonoran, and Chihuahuan deserts. His dissertation focuses on determining the source populations of Sahara mustard and whether plasticity in functional traits is allowing the species to spread. Funds from the Forrest Shreve Student Research Fund will be used to process samples for leaf stable isotopes and elemental stoichiometry, allowing for a comparison of functional traits indicative of local adaptation and the species' plasticity. Daniel was a National Park Service Young Leaders in Climate Change Fellow and a NSF EAPSI Research Fellow. Learn more about the August 7-12, 2017 ESA Annual Meeting on the meeting website: http://esa. ESA welcomes attendance from members of the press and waives registration fees for reporters and public information officers. To apply, please contact ESA Communications Officer Liza Lester directly at llester@esa.org. The Ecological Society of America (ESA), founded in 1915, is the world's largest community of professional ecologists and a trusted source of ecological knowledge, committed to advancing the understanding of life on Earth. The 10,000 member Society publishes five journals and a membership bulletin and broadly shares ecological information through policy, media outreach, and education initiatives. The Society's Annual Meeting attracts 4,000 attendees and features the most recent advances in ecological science. Visit the ESA website at http://www. .


News Article | February 27, 2017
Site: www.eurekalert.org

With an estimated 12 million loaves sold in the UK every year, bread remains a staple of the British diet. In a groundbreaking study researchers from the University of Sheffield have now calculated the environmental impact of a loaf of bread and which part of its production contributes the most greenhouse gas. The group of interdisciplinary researchers from the University's Grantham Centre for Sustainable Futures, analysed the complete process from growing and harvesting the wheat; milling the grain; producing the flour; baking the bread and the production of the final product, ready to be sold by retailers. The findings, published today (27 February 2017) in the journal Nature Plants, show ammonium nitrate fertiliser used in wheat cultivation contributes almost half (43 per cent) of the greenhouse gas emissions - dwarfing all other processes in the supply chain. Dr Liam Goucher, N8 Agrifood Research Fellow from the University of Sheffield who carried out the study, said: "Consumers are usually unaware of the environmental impacts embodied in the products they purchase - particularly in the case of food, where the main concerns are usually over health or animal welfare. "There is perhaps awareness of pollution caused by plastic packaging, but many people will be surprised at the wider environmental impacts revealed in this study. "We found in every loaf there is embodied global warming resulting from the fertiliser applied to farmers' fields to increase their wheat harvest. This arises from the large amount of energy needed to make the fertilizer and from nitrous oxide gas released when it is degraded in the soil." How to produce sufficient healthy and affordable food for the world's growing and more demanding population, whilst protecting the environment is one of the biggest challenges of the 21st century. It is estimated that up to 60 per cent of agricultural crops are now grown with the use of fertilisers. Although they can dramatically boast the growth of plants and vegetables - assisting the growing demand of food yields - fertilisers consist of substances and chemicals such as methane, carbon dioxide, ammonia and nitrogen. The emissions from these substances in synthetic fertilisers contribute to greenhouse gases. Professor Peter Horton FRS, Chief Research Advisor to the Grantham Centre for Sustainable Futures at the University of Sheffield and corresponding author of the paper, said: "Our findings bring into focus a key part of the food security challenge - resolving the major conflicts embedded in the agri-food system, whose primary purpose is to make money not to provide sustainable global food security. "High agricultural productivity - necessary for profit for farmers, agri-businesses and food retailers, whilst also keeping prices low for consumers - currently requires high levels of application of relatively cheap fertilisers." He added: "With over 100 million tonnes of fertiliser used globally each year to support agricultural production this is a massive problem, but environmental impact is not costed within the system and so there are currently no real incentives to reduce our reliance on fertiliser. "How to achieve sustainable global food security is not only a technical question but a political economic one, and requires interdisciplinary research of the kind we do here at Sheffield." The study was made possible by a pioneering collaboration with the agricultural and food manufacturing sector developed by Richard Bruce, a co-author of the paper and Business Engagement Lead for the Grantham Centre for Sustainable Futures at the University of Sheffield. The data analysed in the study was processed using an advanced life-cycle assessment tool - SCEnAT - developed by Professor Lenny Koh, Director of the Advanced Resource Efficiency Centre at the University's Management School and co-author of the paper. "This tool handles large and complex data sets and yielding data on the environmental impact, including greenhouse gas emissions of all the stages in the supply chain," said Professor Koh. "The tool identifies the processes that yield the most impact - the hotspots. "The findings raise a very important issue - whose responsibility is it to bring about the implementation of these interventions: the fertiliser manufacturer, the farmer, the retailer or the consumer? "There is a growing recognition for a range of industrial processes of the notion of extended producer responsibility - the producer being responsible for downstream impact, expanded to the idea of shared producer and consumer responsibility. The consumer is key, whether being persuaded to pay more for a greener product or by applying pressure for a change in practice." The paper also highlights the solutions available which could potentially reduce these impacts in the future. Co-author Professor Duncan Cameron, Co-director of the P3 Centre for Translational Plant and Soil Science explains: "The fertiliser problem is solvable - through improved agronomic practices". "These harness the best of organic farming combined with new technologies to better monitor the nutritional status of soils and plants and to recycle waste and with the promise of new wheat varieties able to utilise soil nitrogen more efficiently". The Grantham Centre at the University of Sheffield is an ambitious and innovative collaboration between the University of Sheffield and the Grantham Foundation for the Protection of the Environment. For more information please visit http://grantham. P3 is a centre of excellence for translational plant and soil science using the breadth of plant and soil science expertise within the University of Sheffield to find suitable solutions to agricultural problems. To find out more please visit http://p3. The Advanced Resource Efficiency Centre (AREC) at the University of Sheffield is a facility to promote the collaboration between industry and academia. It provides a platform for access to policy makers, in order to meet the challenge of promoting resource efficiency and sustainability across supply chains. The concept of AREC as a facility is to enable the creation of competitive advantage through developing resource sustainable supply chains, built on a strong foundation of government policy initiatives. AREC supports the development of resource sustainable supply chains by proposing new ways of reducing risk for partners in overcoming the challenges of resource availability. Through AREC, Small & Medium sized Enterprises (SMEs) can join in collaboration with larger industrial partners and benefit from cutting edge academic research and skills. For more information please visit: http://www. With almost 27,000 of the brightest students from over 140 countries, learning alongside over 1,200 of the best academics from across the globe, the University of Sheffield is one of the world's leading universities. A member of the UK's prestigious Russell Group of leading research-led institutions, Sheffield offers world-class teaching and research excellence across a wide range of disciplines. Unified by the power of discovery and understanding, staff and students at the university are committed to finding new ways to transform the world we live in. Sheffield is the only university to feature in The Sunday Times 100 Best Not-For-Profit Organisations to Work For 2017 and was voted number one university in the UK for Student Satisfaction by Times Higher Education in 2014. In the last decade it has won four Queen's Anniversary Prizes in recognition of the outstanding contribution to the United Kingdom's intellectual, economic, cultural and social life. Sheffield has six Nobel Prize winners among former staff and students and its alumni go on to hold positions of great responsibility and influence all over the world, making significant contributions in their chosen fields. Global research partners and clients include Boeing, Rolls-Royce, Unilever, AstraZeneca, Glaxo SmithKline, Siemens and Airbus, as well as many UK and overseas government agencies and charitable foundations. For further information, please visit: http://www.


News Article | February 22, 2017
Site: www.eurekalert.org

Australia's Ross River Virus (RRV) could be the next mosquito-borne global epidemic according to a new research study led by the University of Adelaide and The Australian National University. The virus has been thought to be restricted largely to Australia and Papua New Guinea where it is harboured by marsupial animals, specifically kangaroos and wallabies, and spread by mosquitoes. Published online ahead of print in the International Journal of Infectious Diseases, the research shows that the virus may have been circulating silently in the South Pacific ever since a large epidemic of more than 500,000 cases in 1979-80, thought to have been started by an infected Australian tourist who travelled to Fiji. "Ross River Virus is found naturally in Australia, where it was circulating in kangaroos and wallabies long before the arrival of the first Australians over 40,000 years ago," says one of the project leaders Professor Phil Weinstein, Professorial Research Fellow with the University of Adelaide's School of Biological Sciences. "When humans arrived, first Aboriginal Australians and then Europeans, they were bitten by the same mosquitoes and became infected: they had all of the sore joints, fever, rash, and fatigue that we associate with the disease today. Although RRV has never killed anyone, it can be extremely debilitating for several months, and up to years in a few unlucky individuals." The 1979 epidemic in the Pacific Islands Countries and Territories was the first time that RRV had 'escaped' from its marsupial reservoir. But without marsupials, the epidemic burned itself out the following year - or so it was thought. "The first clues about local transmission in the Pacific Islands came when more recent tourists from New Zealand and Canada who had been to the South Pacific, but not Australia, were diagnosed with RRV when they returned home," Professor Weinstein says. In partnership with French collaborators in Tahiti and France, the researchers tested blood samples of American Samoans. "We were surprised to find that of those who were born after the 1979-1980 epidemic and had lived in American Samoa their whole lives, a massive 63% had antibodies to RRV, strongly suggesting local transmission of the virus after 1980," says Dr Colleen Lau, NHMRC Research Fellow in ANU's College of Medicine, Biology and Environment. "There are no marsupials in American Samoa, so the only reasonable conclusion is that the virus was able to circulate in local mammals rather than marsupials. If RRV can circulate in non-marsupials in the South Pacific, then it can find a home anywhere in the world. "Isolation of the virus from non-marsupials will provide us with definitive evidence that RRV can become endemic globally." Professor Weinstein says: "With the large number of Australians now travelling, it would not be unreasonable to expect one or more tourists to carry RRV overseas to seed a new epidemic. With the right conditions, this could take off globally in exactly the same way that Zika did."


News Article | February 22, 2017
Site: phys.org

Previous research showed that animals that breed in this way are more likely to live in harsher climates, such as deserts, than those who go it alone. Without any evidence for why this happens, scientists drew the intuitive conclusion that team thinking was at play, and larger family structures were formed as a survival strategy. However, the new findings from Oxford's Department of Zoology have turned these previous conclusions on their head, proving that communal family dynamics are often built before animals enter difficult climates, and that the two are actually not related. From observing 4,707 bird species, the team collated and analysed data to test competing explanations for how much environmental conditions influence and drive species' decision to live communally. These potential explanations included: entering harsh environments in a large family group offers stronger chances of survival than as an individual; there is in fact no relationship between the two at all; and that a third variable may be at play, such as female polyandry, when the mother has multiple partners. The study found that parental relationships - specifically whether they were polyandrous or monogamous plays a key role in whether animal families stay together as a group or not. A cooperative living structure was more likely to be favoured when both parental genes were shared by siblings, a trait known as "kin selection." Bolstered by this dynamic the groups are then able to enter difficult climates, and set up home in new territories, that they may not have been able to survive in alone. The research was conducted in partnership with the University of Lund, Sweden, Columbia University, USA and Washington University, St Louis, USA. The full study features in the journal Nature Ecology & Evolution. Professor Ashleigh Griffin, Research Fellow in the Department of Zoology and co-author of the study said: "For decades, biologists have noted that animals living in harsh desert environments often live in cooperative groups. This seems to make intuitive sense - when times are hard, it may take teamwork to survive. We tested this hypothesis in an analysis of over 2,000 species of birds, looking at whether species were cooperative and where they lived. Surprisingly, we found no evidence to support the widely held assumption that species in the desert were more likely to become cooperative. Instead, cooperation evolves as a result of close genetic bonds in family groups. These cooperative family groups are then better able to invade new territory, where the climate is too harsh for uncooperative, solitary species to survive." While survival is not the reason that animals choose to breed cooperatively, it is a definite advantage in extreme environments like the desert. Species that are known for their familial helping behaviour, such as starlings and meerkats, can live anywhere. Non-cooperative species, such as puffins and penguins, tend to only be found in specific environments. Professor Griffin added: "Cooperative species are more effective pioneers, able to exploit harsh environments that are too tough for most other species that raise offspring on their own or in pairs."


News Article | February 22, 2017
Site: www.eurekalert.org

It's not every day that you're congratulated in a full-page ad in The New York Times. That's a special recognition University of Delaware professor Catherine Leimkuhler Grimes received on Tuesday, Feb. 21, when she and other selected scientists were announced as Sloan Research Fellowship winners. The prestigious two-year, $60,000 fellowship is awarded annually to 126 early-career scholars from the U.S. and Canada whose accomplishments mark them as the next generation of scientific leaders. "The Sloan Research Fellows are the rising stars of the academic community," said Paul L. Joskow, president of the Alfred P. Sloan Foundation. "Through their achievements and ambition, these young scholars are transforming their fields and opening up entirely new research horizons. We are proud to support them at this crucial stage of their careers." Grimes, assistant professor in UD's Department of Chemistry and Biochemistry, will use her fellowship to investigate how chronic inflammatory diseases, such as asthma and Crohn's disease, arise. Her work focuses on organisms you can't see and can't live without -- bacteria. Each of us carts around about three pounds of bacteria, in our stomachs and intestines, on our skin and lots of other places. Most are beneficial, helping with myriad functions, from digesting lunch to healing a bruise. Some are harmful, causing infections and disease. Bacteria naturally shed tiny fragments of their cell wall as they grow, like lint from a jacket. If these fragments come from harmful bacteria, your immune system responds accordingly by waging war on the nasty invaders. Sometimes, however, a case of mistaken identity occurs -- the cell wall fragments may have been sloughed by beneficial bacteria, but the immune system misreads them and winds up attacking healthy tissue. That scenario has been implicated in Crohn's disease, rheumatoid arthritis, asthma and cancer. Grimes hypothesizes that these diseases erupt from a discrete set of bacterial cell wall fragments and that the body has mechanisms to sense such molecules. To test this hypothesis, she and her laboratory group are enlisting a full-court press of scientific techniques, from synthetic organic chemistry, to molecular biology, immunology, biochemistry and microbiology. "I feel extremely lucky to have such a diverse group of research students who are just as dedicated to these projects as I am," Grimes said. "Together we are unveiling how our immune systems keep track of both the good and bad bacteria." As a Sloan Research Fellow, Grimes is in prestigious company. In her own department at UD, she notes that her colleagues Joel Rosenthal, Doug Taber, Thomas Beebe and Klaus Theopold -- all past winners of the fellowship -- provide excellent examples of dynamic research programs. In the wider scientific community, past awardees include such towering figures as physicist Richard Feynman and Murray Gell-Mann and game theorist John Nash. Forty-three former fellows have received a Nobel Prize in their respective field, 16 have won the Fields Medal in mathematics, 69 have received the National Medal of Science, and 16 have won the John Bates Clark Medal in economics, including every winner since 2007. Grimes was named a Pew Scholar in the Biomedical Sciences by The Pew Charitable Trusts in 2014, won the Cottrell Scholar Award in 2015 and received the National Science Foundation's Faculty Early Career Development Award in 2016. She graduated summa cum laude from Villanova University, earned her master's degree in chemistry from Princeton University and her doctorate in chemistry from Harvard. She joined the UD faculty in 2011. Established in 1934 by Alfred Pritchard Sloan Jr., then-president and chief executive officer of the General Motors Corp., the Sloan Foundation makes grants in support of original research and education in science, technology, engineering, mathematics and economics. The foundation is based in New York City.


News Article | March 2, 2017
Site: phys.org

The researchers used Micronova’s cleanrooms and, in particular, a reactor designed for gallium nitride manufacturing. The image shows a six-inch substrate in the MOVPE reactor before manufacturing. Credit: Aalto University / Jori Lemettinen In cooperation with Okmetic Oy and the Polish ITME, researchers at Aalto University have studied the application of SOI (Silicon On Insulator) wafers, which are used as a platform for manufacturing different microelectronics components, as a substrate for producing gallium nitride crystals. The researchers compared the characteristics of gallium nitride (GaN) layers grown on SOI wafers to those grown on silicon substrates more commonly used for the process. In addition to high-performance silicon wafers, Okmetic also manufactures SOI wafers, in which a layer of silicon dioxide insulator is sandwiched between two silicon layers. The objective of the SOI technology is to improve the capacitive and insulating characteristics of the wafer. "We used a standardised manufacturing process for comparing the wafer characteristics. GaN growth on SOI wafers produced a higher crystalline quality layer than on silicon wafers. In addition, the insulating layer in the SOI wafer improves breakdown characteristics, enabling the use of clearly higher voltages in power electronics. Similarly, in high frequency applications, the losses and crosstalk can be reduced," explains Jori Lemettinen, a doctoral candidate from the Department of Electronics and Nanoengineering. "GaN based components are becoming more common in power electronics and radio applications. The performance of GaN based devices can be improved by using a SOI wafer as the substrate," adds Academy Research Fellow Sami Suihkonen. Growth of GaN on a silicon substrate is challenging. GaN layers and devices can be grown on substrate material using metalorganic vapor phase epitaxy (MOVPE). When using silicon as a substrate the grown compound semiconductor materials have different coefficients of thermal expansion and lattice constants than a silicon wafer. These differences in their characteristics limit the crystalline quality that can be achieved and the maximum possible thickness of the produced layer. 'The research showed that the layered structure of an SOI wafer can act as a compliant substrate during gallium nitride layer growth and thus reduce defects and strain in the grown layers," Lemettinen notes. GaN based components are commonly used in blue and white LEDs. In power electronics applications, GaN diodes and transistors, in particular, have received interest, for example in frequency converters or electric cars. It is believed that in radio applications, 5G network base stations will use GaN based power amplifiers in the future. In electronics applications, a GaN transistor offers low resistance and enables high frequencies and power densities. More information: Jori Lemettinen et al. MOVPE growth of GaN on 6-inch SOI-substrates: effect of substrate parameters on layer quality and strain, Semiconductor Science and Technology (2017). DOI: 10.1088/1361-6641/aa5942


News Article | February 15, 2017
Site: phys.org

The word 'replicant' evokes thoughts of a sci-fi world where society has replaced common creatures with artificial machines that replicate their behaviour. Now researchers from Singapore have shown that if such machines are ever created, they'll run more efficiently if they harness quantum theory to respond to the environment. This follows the findings of a team from the Centre for Quantum Technologies (CQT), published 10 February in npj Quantum Information. The team investigated 'input-output processes', assessing the mathematical framework used to describe arbitrary devices that make future decisions based on stimuli received from the environment. In almost all cases, they found, a quantum device is more efficient because classical devices have to store more past information than is necessary to simulate the future. "The reason turns out to be quantum theory's lack of a definitive reality," says co-author Mile Gu, an Assistant Professor at the Nanyang Technological University, Singapore, who is affiliated with CQT. "Quantum mechanics has this famous feature where some properties of quantum particles are not just unknown before they are measured, but fundamentally do not exist in a definitive state prior to the act of measurement," he says. The physics only specifies the probabilities the system collapses to each possible value once the measurement is performed. That lets the quantum system, in a sense, do more with less. Co-author Jayne Thompson, a Research Fellow at CQT, explains further: "Classical systems always have a definitive reality. They need to retain enough information to respond correctly to each possible future stimulus. By engineering a quantum device so that different inputs are like different quantum measurements, we can replicate the same behaviour without retaining a complete description of how to respond to each individual question." Andrew Garner, another Research Fellow at CQT, and Vlatko Vedral, a Principal Investigator at CQT and Professor at the University of Oxford, also contributed to the paper. The findings advance earlier work. In 2012, Vedral, Gu and others proved a similar result for another class of problems known as stochastic processes. These are systems that have dynamics independent of external stimuli. That result was just put to experimental test by collaborators from Griffith University in Australia. They constructed a real life quantum simulator of a stochastic process [Science Advances 3, e1601302 (2017)]. This proof-of-principle experiment used just two particles of light. The first simulations of input-output processes will probably be small-scale too, but Gu hopes to ultimately see quantum technologies simulating how complex systems will react and evolve in real life situations. "Input-output processes are ubiquitous in nature," says Vedral. "Every entity is essentially an input-output process, from neural networks that process past inputs to make future decisions, to seeds that determine when to germinate based on external stimuli," he says. "Humans have long been fascinated with the idea of replicating nature through machines, from Leonardo da Vinci's famous mechanical knight to speculative fiction of future androids like Philip K. Dick's 'Do Androids Dream of Electric Sheep' that inspired the Blade Runner film," Gu says. "Perhaps androids in the future, engineered by an advanced civilization obsessed with efficiency, will instead dream of quantum sheep." Explore further: Quantum RAM: Modelling the big questions with the very small More information: Jayne Thompson et al, Using quantum theory to simplify input–output processes, npj Quantum Information (2017). DOI: 10.1038/s41534-016-0001-3


We contribute to existing knowledge translation (KT) literature by developing the notion of 'enactment' and illustrate this through an interpretative, comparative case-study analysis of three Collaborations for Leadership in Applied Health Research and Care (CLAHRC) initiatives. We argue for a focus on the way in which the CLAHRC model has been 'enacted' as central to the different KT challenges and capabilities encountered. A comparative, mixed method study created a typology of enactments (Classical, Home-grown and Imported) using qualitative analysis and social network analysis. We identify systematic differences in the enactment of the CLAHRC model. The sources of these different enactments are subsequently related to variation in formative interpretations and leadership styles, the implementation of different governance structures, and the relative epistemic differences between the professional groups involved. Enactment concerns the creative agency of individuals and groups in constituting a particular context for their work through their local interpretation of a particular KT model. Our theory of enactment goes beyond highlighting variation between CLAHRCs, to explore the mechanisms that influence the way a particular model is interpreted and acted upon. We thus encourage less focus on conceptual models and more on the formative role played by leaders of KT initiatives.


News Article | February 24, 2017
Site: www.eurekalert.org

Gene transfers are particularly common in the antibiotic-resistance genes of Streptococcus pneumoniae bacteria Gene transfers are particularly common in the antibiotic-resistance genes of Streptococcus pneumoniae bacteria. When mammals breed, the genome of the offspring is a combination of the parents' genomes. Bacteria, by contrast, reproduce through cell division. In theory, this means that the genomes of the offspring are copies of the parent genome. However, the process is not quite as straightforward as this due to horizontal gene transfer through which bacteria can transfer fragments of their genome to each other. As a result of this phenomenon, the genome of an individual bacterium can be a combination of genes from several different donors. Some of the genome fragments may even originate from completely different species. In a recent study combining machine learning and bioinformatics, a new computational method was developed for modelling gene transfers between different lineages of a bacterial population or even between entirely different bacterial species. The method was used to analyse a collection of 616 whole-genomes of a recombinogenic pathogen Streptococcus pneumoniae. In the study, several individual genes in which gene transfers were considered particularly common were identified. These genes also included genes causing resistance to antibiotics. 'In the case of antibiotic-resistance genes, the number of gene transfers may be related to how useful these genes are to bacteria and to the resulting selection pressure', says Academy Research Fellow Pekka Marttinen from the Aalto University Department of Computer Science. 'The study will not provide a direct solution to antibiotic resistance because this would require a profound understanding of how the resistance occurs and spreads. Nevertheless, knowing the extent to which gene transfer occurs between different species and lineages can help in improving this understanding', he explains. The study was able to show that gene transfer occurs both within species and between several different species. The large number of transfers identified during the study was a surprise to the researchers. 'Previous studies have shown that gene transfers are common in individual genes, but our team was the first to use a computational method to show the extent of gene transfer across the entire genome', Marttinen says. 'The method also makes it possible to effectively examine ancestral gene transfers for the first time, which is important in examining transfers between different species.' Molecular Biology and Evolution published the results in February. Article: Rafal Mostowy, Nicholas J. Croucher, Cheryl P. Andam, Jukka Corander, William P. Hanage and Pekka Marttinen: Efficient inference of recent and ancestral recombination within bacterial populations. Molecular Biology and Evolution 2017. DOI: 10.1093/molbev/msx066. Caption: Mosaic pneumococcal population structure caused by horizontal gene transfer is shown on the left for a subset of genes. Matrix on the right shows a genome-wide summary of the relationships between the bacteria, ranging from blue (distant) to yellow (closely related). Photo: Pekka Marttinen

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