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Kilwon Cho and the team's research was published in Journal of the American Chemical Society as a cover article and highlighted by the editors in JACS Spotlights. Credit: Journal of American Chemical Society Polymer semiconductors, which can be processed on large-area and mechanically flexible substrates with low cost, are considered as one of the main components for future plastic electronics. However, they, especially n-type semiconducting polymers, currently lag behind inorganic counterparts in the charge carrier mobility - which characterizes how quickly charge carriers (electron) can move inside a semiconductor - and the chemical stability in ambient air. Recently, a joint research team, consisting of Prof. Kilwon Cho and Dr. Boseok Kang with Pohang University of Science and Technology, and Prof. Yun-Hi Kim and Dr. Ran Kim with Gyungsang National University, has developed a new n-type semiconducting polymer with superior electron mobility and oxidative stability. The research outcome was published in Journal of the American Chemical Society (JACS) as a cover article and highlighted by the editors in JACS Spotlights. The team modified a n-type conjugated polymer with semi-fluoroalkyl side chains - which are found to have several unique properties, such as hydrophobicity, rigidity, thermal stability, chemical and oxidative resistance, and the ability to self-organize. As a result, the modified polymer was shown to form a superstructure composed of polymer backbone crystals and side-chain crystals, resulting in a high degree of semicrystalline order. The team explained this phenomenon is attributed to the strong self-organization of the side chains and significantly boosts charge transport in polymer semiconductors. Prof. Cho emphasized "We investigated the effects of semi-fluoroalkyl side chains of conjugated polymers at the molecular level and suggested a new strategy to design highly-performing polymeric materials for next-generation plastic electronics". This research was supported by the Center for Advanced Soft Electronics under the Global Frontier Research Program and the National Research Foundation (NRF) of Korea funded by the Ministry of Science, ICT and Future Planning.

Halstead S.B.,Research Program | Thomas S.J.,U.S. Army
Expert Review of Vaccines | Year: 2011

Japanese encephalitis virus (JEV), a flavivirus maintained in a zoonotic cycle and transmitted by the mosquito Culex tritaeniorhynchus, causes epidemics of encephalitis throughout much of Asia. Resident populations, including short- or long-term visitors to enzootic regions, are at risk of infection and disease. For the past several decades, killed viral vaccines prepared in tissue culture or mouse brain have been used effectively to immunize travelers and residents of enzootic countries. Cost, efficacy and safety concerns led to the development of a live-attenuated virus vaccine (SA14-14-2) and more recently, to the licensure in the USA, Europe, Canada, and Australia of a purified inactivated, tissue culture-based Japanese encephalitis vaccine (IXIARO®, referred to as IC51; Intercell AG, Vienna, Austria). In addition, a live-attenuated yellow fever-Japanese encephalitis chimeric vaccine (IMOJEV™, referred to as Japanese encephalitis-CV; Sanofi Pasteur, Lyon, France) was recently licensed in Australia and is under review in Thailand. A broad portfolio of safe and effective Japanese encephalitis vaccines has become available to meet the needs of at-risk populations; when appropriately delivered, these new vaccines should greatly diminish the burden of disease. © 2011 Expert Reviews Ltd.

Wilder-Smith A.,National University of Singapore | Halstead S.,Research Program
Current Opinion in Infectious Diseases | Year: 2010

Purpose of review: Japanese encephalitis is the most common vaccine-preventable viral encephalitis in Asia. In view of the production cessation of the inactivated mouse brain-derived Japanese encephalitis vaccine, it is timely to provide an update on new Japanese encephalitis vaccines and revised vaccine recommendations. Recent findings: A new inactivated, adjuvanted, Vero cell-culture-based Japanese encephalitis vaccine, IC51, was licensed in Europe and the United States in 2009. Administered in a two-dose regimen at 0 and 28 days, it was shown to be well tolerated and produce high seroconversion rates. In addition, Chimerivax Japanese encephalitis, a novel live-attenuated one-dose chimeric vaccine comprising the structural genes of SA 14-14-2 virus and nonstructural genes of yellow fever 17D virus, is in the process of getting licensed in Australia and in south east Asia. Summary: Previous recommendations for Japanese encephalitis vaccination of travelers were predicated on minimizing exposure to a mouse-brain-derived vaccine with a poorly understood and worrisome safety profile, whereas the risk of acquiring Japanese encephalitis itself during travel was assessed to be relatively low. With the availability of a new cell-culture-derived vaccine IC51 with an excellent safety profile, it is appropriate to reconsider benefit-risk considerations for the vaccination of travelers. These considerations are reflected in the March 2010 revised recommendations by the United States Advisory Committee on Immunization Practices. © 2010 Lippincott Williams & Wilkins.

News Article
Site: www.reuters.com

In truth, the farmer from Gavu, a village in arid Hwange District, about 450 km north of Bulawayo, can't control the weather. But he can predict it fairly accurately. Using a well-worn record book, a green plastic rain gauge, and a mobile phone on which he receives climate-related information via SMS, Tshuma makes farming decisions based on the weather patterns in his area, including when to plant, how to till the soil and how much fertilizer to apply. Tshuma is one of a thousand small-scale farmers in southern Zimbabwe benefiting from a project called Climate Smart Agriculture: Combating the El Niño Phenomenon. Launched in Jambezi ward in 2013, the project is part of the nation's plan to manage threats such as droughts by strengthening systems to provide early warnings about risks to agriculture from climate change and related weather problems. Bringing together the Ministry of Agriculture's Department of Agricultural Technical and Extension Services (AGRITEX), the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), and local telecommunications services provider ECONET, the project teaches farmers to use weather-monitoring techniques and climate-smart agriculture practices to maintain food security in rain-scarce parts of the country. Last season, Tshuma and his wife Simnai harvested 1.5 tonnes of millet, one tonne of sorghum, and a quarter tonne of groundnuts. This season he expects to harvest four tonnes of millet and nearly 2.5 tonnes of sorghum, despite a drought that has slashed neighbors' maize harvests. "This year … I have done so much better in my fields than some of my neighbors that some people say I am irrigating my crops or I have goblins who work magic. But that is not true,” Tshuma said. With $30,000 of funding from ICRISAT, the project teaches techniques to help farmers improve their harvests while cutting their costs. Those includes mulching fields to save water, planting crops in dug-out basins filled with manure, planting different types of crops together in a field and using fertilizer in small doses just where it is needed. It also aims to convince farmers to swap their traditional crops for more drought-tolerant ones, no easy feat in a region where maize is a diet staple. "Sorghum and millet are not only climate smart but nutritionally smart. We call them smart foods because they are good for us, good for the environment and good for smallholder farmers to manage climate change, diversify their income and increase their profitability," said David Bergvinson, ICRISAT’s director general. Switching to more resilient crops is crucial because “climate change is hitting us hard and fast,” he said. According to the United Nations Food and Agriculture Organization, climate-smart agriculture can help farmers produce more and become more resilient to shocks, boosting food security even as climate change-related extreme weather strengthens. The practices and techniques the project promotes are part of Zimbabwe’s plan to deal with climate change, submitted as part of a new global climate deal agreed in Paris last December. The current El Niño-induced drought in Zimbabwe is one of the worst the country has seen in a quarter century. More than 3 million Zimbabweans are facing hunger due to a maize shortfall of more than 1 million tonnes, about half of what the country requires each year. Zimbabwe has been forced to declare a state of national disaster and is appealing for $1.6 billion in food aid. A recent study by the CGIAR Research Program on Climate Change, Agriculture and Food Security says global warming will continue to affect staple food crops like bananas, maize and beans in sub-Saharan Africa unless farmers learn to adapt. According to the study, 30 percent of sub-Saharan Africa's maize-growing areas, including in Zimbabwe, need to switch to different crops within the next decade. "Climate change is reducing the viability of maize production and, increasingly, we are envisaging that semi-arid regions of Zimbabwe could only be growing drought-tolerant grains in the near future," Danisile Hikwa, principal director of the agriculture ministry's Department of Research and Specialist Services, told farmers in Hwange District recently. In Gavu, Tshuma has already seen the benefits of changing what and how he farms. After joining the agriculture adaptation project when it first started three years ago, he now earns an average of $300 per season from selling his farm crops once he has fed his family. He has cut back on growing maize and now harvests enough sorghum and millet to sell to his neighbors and to a Jambezi small grain processing plant, run by an association of farmers that grow, process, and markets products made from drought-tolerant crops. Tshuma is so convinced about the need to adapt that he is mentoring 20 farmers through one of 50 climate field schools run jointly by ICRISAT and AGRITEX in Hwange District. He admits some of his neighbors have been reluctant to adopt the changes, particularly the labor involved in digging basins. But his success is winning them over, he said. "Millet and sorghum are the crops for survival in this time of drought," he said. "Farmers have to work hard to survive - it is not magic."

News Article | April 12, 2016
Site: cleantechnica.com

A new report released by the White House warns that climate change is an imminent and growing threat to public health, and that extreme heat will kill around 27,000 US residents per year by 2100. A science advisor to the Obama administration by the name of John Holdren commented on the report at a recent press conference, noting that extreme heat waves will make outdoor work periodically “impossible:” “People who work outdoors will be unable to control their body temperature and will die. This is a really, really big deal.” The report — titled “The Impacts of Climate Change on Human Health in the United States: A Scientific Assessment,” and put together by the US Global Change Research Program — notes that anthropogenic climate change will lead to growing air pollution levels, expanding waterborne illness prevalence, the expansion of toxin presence in the US food supply, and the weakening and overburdening of healthcare infrastructure. “For the first time in history we’ve been able to show it’s not just about polar bears and melting ice caps, it’s about our families and about our future,” stated Gina McCarthy, the administrator of the Environmental Protection Agency (EPA) administrator. “Every part of the US is impacted now by climate and is going to be increasingly impacted if we do not take action now to reduce those impacts.” The 332-page report, with contributions from hundreds of scientists from universities across the country, was released as part of the Obama administration’s Climate Action Plan. The plan aims to reduce the US contribution to global warming by cutting greenhouse gas emissions by up to 28% by 2025. The US is a party to the Paris climate agreement, which aims to keep global warming from exceeding 2° C (3.6° F). …The report says climate change will threaten public health by increasing the severity and frequency of existing health problems and by posing unprecedented health problems — such as the spread of tick-borne diseases like Lyme disease — in places where they have never occurred before. As temperatures warm, mosquito-born illnesses such as West Nile virus, malaria, and dengue fever, could also spread throughout the US, sickening and killing Americans in the process, the report said. Air quality is expected to decline because of increased ozone pollution and a greater number of severe wildfires, leading to worsened allergy and asthma conditions and deaths. Poor water quality caused by climate change could also lead to the spread of disease, according to the report. Warmer temperatures will warm lakes and streams, contributing to blooms of toxic algae, while coastal flooding from rising seas and higher storm surge could overwhelm urban wastewater systems and expose residents to waterborne pathogens. America’s food supply is vulnerable to toxins and diseases spread by warming temperatures, the report said. Higher sea surface temperatures will lead to more mercury in seafood while warming will lead to the wider spread of pathogens, pests and parasites in the food supply such as norovirus, listeria, salmonella, E. coli and others. Increasing atmospheric carbon dioxide also reduces the concentrations of proteins and minerals in some plant species, reducing the nutritional value of wheat and rice, according to the report. Extreme weather could also severely damage America’s food distribution infrastructure, leaving people without access to nutritional food. Mental health is also likely to be affected on the mass scale, according to the director of At-Risk, Behavioral Health and Community Resilience at the US Department of Health and Human Services, Daniel Dodgen. Through the impacts of extreme weather on living situation (housing, jobs, family deaths, health problems, etc), the mental health of a great many people will be affected as well, according to Dodgen.   Drive an electric car? Complete one of our short surveys for our next electric car report.   Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.  

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