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991.
The European Union (EU) has set a target to reduce its greenhouse gas (GHG) emissions at least 10 % below the 2005 levels by 2020 in the non-Emission Trading Sector (non-ETS). As part of this, each Member State has a binding national emission limitation target for the non-ETS sector. Finland’s target, examined as a case study in this paper, is to reduce emissions at least 16 % below 2005 levels by 2020. The objective of this study is to find cost optimal mitigation portfolios that meet Finland’s reduction target and to analyze the risks of not attaining the emission target or exceeding the assumed costs. The question was addressed with a stochastic optimization model, Stochastic Optimization of non-ETS Emissions (SONETS) selecting separate mitigation measures that meet the target on expectation. The results show that optimal portfolios include relatively high uncertainty both in costs and achieved reductions. The prices of crude oil and diesel, and the abatement cost of reducing hydrofluorocarbon (HFC) emissions seem to account for the majority of uncertainty regarding total costs. The baseline predictions for various non-ETS subsectors (such as transport and agriculture) were found to have the greatest contribution to the uncertainty of attaining emission target. The results also show that some abatement actions are chosen in nearly all efficient portfolios, while other actions are seldom chosen. For example replacing oil burners in the end of technical life time or recovery of methane (CH4) from waste are often chosen whereas ban of landfilling of organic waste is chosen extremely seldom. It also seems that the results are somewhat sensitive to the inclusion or exclusion of the interdependencies of mitigation measures.  相似文献   
992.
The automotive industry is developing designs and manufacturing processes for a new generation of electric motors intended for use in hybrid and electric vehicles. This paper is focused on using solid-state welding to join rectangular wires in the fabrication of motor stators. Resistance welding has not typically been applied to copper due to its very high electrical conductivity; however through optimization of the current and pressure profiles, excellent quality copper-to-copper joints have been demonstrated with a technique known as resistance mash welding. A better understanding of resistance mash welding characteristics will help advancements in its application for stators. The limitations of this application will be discussed.  相似文献   
993.
Shellfish-Borne Viral Outbreaks: A Systematic Review   总被引:1,自引:0,他引:1  
Investigations of disease outbreaks linked to shellfish consumption have been reported in the scientific literature; however, only few countries systematically collate and report such data through a disease surveillance system. We conducted a systematic review to investigate shellfish-borne viral outbreaks and to explore their distribution in different countries, and to determine if different types of shellfish and viruses are implicated. Six databases (Medline, Embase, Scopus, PubMed, Eurosurveillance Journal and Spingerlink electronic Journal) and a global electronic reporting system (ProMED) were searched from 1980 to July 2012. About 359 shellfish-borne viral outbreaks, alongside with nine ProMED reports, involving shellfish consumption, were identified. The majority of the reported outbreaks were located in East Asia, followed by Europe, America, Oceania, Australia and Africa. More than half of the outbreaks (63.6 %) were reported from Japan. The most common viral pathogens involved were norovirus (83.7 %) and hepatitis A virus (12.8 %). The most frequent type of consumed shellfish which was involved in outbreaks was oysters (58.4 %). Outbreaks following shellfish consumption were often attributed to water contamination by sewage and/or undercooking. Differences in reporting of outbreaks were seen between the scientific literature and ProMED. Consumption of contaminated shellfish represents a risk to public health in both developed and developing countries, but impact will be disproportionate and likely to compound existing health disparities.  相似文献   
994.
Recent events have shown that humans may become infected with some pathogenic avian influenza A viruses (AIV). Since soil and water, including lakes, rivers, and seashores, may be contaminated by AIV excreted by birds, effective methods are needed for monitoring water for emerging viruses. Combining water filtration with molecular methods such as PCR is a fast and effective way for detecting viruses. The objective of this study was to apply a convenient method for the detection of AIV in natural water samples. Distilled water and lake, river, and seawater were artificially contaminated with AIV (H5N3) and passed through a filter system. AIV was detected from filter membrane by real-time RT-PCR. The performance of Zetapor, SMWP, and Sartobind D5F membranes in recovering influenza viruses was first evaluated using contaminated distilled water. SWMP, which gave the highest virus recoveries, was then compared with a pre-filter combined GF/F filter membrane in a trial using natural water samples. In this study, the cellulose membrane SMWP was found to be practical for recovery of AIVs in water. Viral yields varied between 62.1 and 65.9% in distilled water and between 1 and 16.7% in natural water samples. The borosilicate glass membrane GF/F combined with pre-filter was also feasible in filtering natural water samples with viral yields from 1.98 to 7.33%. The methods described can be used for monitoring fresh and seawater samples for the presence of AIV and to determine the source of AIV transmission in an outbreak situation.  相似文献   
995.
Noroviruses are one of important agents that cause acute viral gastroenteritis worldwide. These viruses are belonging to Caliciviridae family and are genetically diverse. To date, there is no valuable data about prevalence of norovirus infection and the dominant genogroup/genotype among Iranian population. The objective of this study was to determine the frequency of norovirus infection in Iranian patients with gastroenteritis referred to three hospitals of Tehran and to specify the dominant genogroup/genotype of this virus among our study population. A total of 293 patients with acute gastroenteritis were included in the study. Detection of norovirus was performed using RT-PCR method and confirmed by direct sequencing with specific designed primers for capsid region of norovirus genome. Phylogenetic analysis was performed using the neighbor-joining method. Norovirus strains identified in our study were subsequently categorized according to previously defined genogroup/genotypes. Of these, norovirus GII was dominant genogroup. Sixty-five percent (17 of 26) of positive samples were determined as GII and 35% (9 of 26) were determined as GI, respectively, in 2008–2009. And among 8 sequenced strains of genogroup II the most frequent genotype was GII.3. The results of this study indicated that norovirus must be considered as one of the infectious causes of acute gastroenteritis among Iranian population. We also found that GII.3 is more prevalent in our study population. To the best of our knowledge there is limited data about the role of noroviruses in children and adults’ acute gastroenteritis among Iranian patients and this prevalence and genotyping report of norovirus infection could be remarkable for further studies.  相似文献   
996.
A framework for analyzing climate change adaptations as actions   总被引:1,自引:0,他引:1  
Developing generalized theories about adaptation to climate change requires common concepts to map different adaptation situations. The paper aims to contribute to this endeavor by presenting a novel framework that conceptualizes adaptations to climate change as actions. The framework is intended to systematically analyze the actor relations involved in adaptations and the barriers to their implementation. By combining established scientific action theories with terminology from the Intergovernmental Panel on Climate Change (IPCC) in an innovative way, it can be used to clarify the notion of adaptation used in adaptation assessments. The framework’s potential is illustrated by a case study on cooling water management in the river Rhine catchment and by the elucidation of some prominent concepts in adaptation research. We show that by framing adaptations as actions, the purpose of adaptations and how they tend to connect up in means-ends-chains becomes crucial. Actors can take different functional roles as exposure unit, operator and receptor of adaptation. A mismatch of these roles can lead to barriers to adaptation, of which we deduce four types: complex actor relations, missing operators, missing means and unemployed means. The case study yields a complex bundle of adaptations, and shows that the potential barriers involved are quite diverse. There is thus no blueprint solution. Although we identify entry points for adaptation, the analysis leads to a skeptical conclusion for adapting cooling water management in the whole Rhine catchment.  相似文献   
997.
Climate change poses a serious threat to sea turtles (Cheloniidae) as their terrestrial reproductive phase is only successful within a limited range of environmental and physical conditions. These conditions are likely to become less optimal as climate change progresses. To date, management and conservation of sea turtles has focused almost entirely on non-climatic stressors, due at least in part to practitioners not knowing what strategies to take and the feasibility and risks of potential strategies. To aid the management of sea turtles in a changing environment, we identified management strategies via a focus workshop and surveys to mitigate the impacts of climate change to the terrestrial reproductive phase of sea turtles. The effectiveness, ecological risks and potential social and logistical constraints associated with implementing each of the identified management strategies is discussed. Twenty management strategies were identified; strategies varied from habitat protection to more active and direct manipulation of nests and the nesting environment. Based on our results, we suggest a three-pronged approach to sea turtle conservation in light of climate change, where managers and researchers should: 1) enhance sea turtle resilience to climate change by mitigating other threats; 2) prioritise implementing the ‘no regret’ and ‘reversible’ management strategies identified here; and 3) fill the knowledge gaps identified to aid the trial and implementation of the potential strategies identified here. By combining these three approaches our collective toolkit of sea turtle management strategies will expand, giving us an array of viable approaches to implement as climate change impacts become more extreme.  相似文献   
998.
We explored the possible future impacts of increased coastal flooding due to sea level rise and the potential adaptation responses of two urban, environmental justice communities in the metropolitan Boston area of Massachusetts. East Boston is predominantly a residential area with some industrial and commercial activities, particularly along the coastal fringe. Everett, a city to the north of Boston, has a diversified industrial and commercial base. While these two communities have similar socioeconomic characteristics, they differ substantially in the extent to which residents would be impacted by increased coastal flooding. In East Boston, a large portion of residents would be flooded, while in Everett, it is the commercial/industrial districts that are primarily vulnerable. Through a series of workshops with residents in each community, we found that the target populations do not have an adaptation perspective or knowledge of any resources that could assist them in this challenge. Furthermore, they do not feel included in the planning processes within their communities. However, a common incentive for both communities was an intense commitment to their communities and an eagerness to learn more and become actively engaged in decisions regarding climate change adaptation. The lessons that can be applied to other studies include 1) images are powerful tools in communicating concepts, 2) understanding existing cultural knowledge and values in adaptation planning is essential to the planning process and 3) engaging local residents at the beginning of the process can create important educational opportunities and develop trust and consensus that is necessary for moving from concept to implementation.  相似文献   
999.
It has been recognized that the involvement of local community is essential to ensure the sustainability of A/R CDM (afforestation/reforestation clean development mechanism) project. This study verifies if the risks of non-permanence and leakage are addressed in a registered small scale A/R CDM project in Vietnam. Workshops, interviews, and a questionnaire survey of local villagers revealed that the project has caused a shortage of land for conventional activities such as grazing, fuel wood collection and shifting cultivation, and consequently posed the risks of project non-permanence and leakage. It is suggested that participation of all stakeholders in the community to the A/R CDM project beyond existing land tenure and adequate carbon benefit sharing according to the level of contribution to the project are required to reduce the risk of non permanence. To ensure the participation, the community should have capability such as consensus building and collective action. Leakage would be minimized if the community has alternative measures to the conventional activities before starting the project. We argue that it is necessary to first develop a community’s capabilities in the readiness phase of any A/R CDM project in order to reduce the risks for the project sustainability, and that new sources of funding are needed for this purpose.  相似文献   
1000.
For a successful enhancement of mechanical properties of metal matrix nanocomposites, a homogeneous nanoparticle dispersion and distribution in the solidified metal is required. Mechanical mixing can be used for initial break-up of agglomerates, and its study can be simplified with dimensional analysis. Using this technique, mixing time and vortex height were assessed while varying fluid properties, impeller angle, and angular speed. Three relevant dimensionless numbers were recognized: the Reynolds (Re), Froude and Galilei (Ga) numbers. Based on blade and impeller shaft angles, a modified Froude number (Fr*) was defined. These parameters were calculated experimentally, varying angular speed from 200 to 1000 rpm for three different impeller angles: 0°, 15° and 30°. This procedure was performed with three fluids: water, and two aqueous glycerin solutions (25% and 50% by volume). Digital images were taken and processed to measure vortex height. Mixing time was measured for water at 0° impeller angle, angular speed ranging from 200 to 1200 rpm. Results showed an optimal dimensionless mixing time with respect to Re. A linear relationship was found between dimensionless vortex height and Fr*. The first had a second order polynomial relationship with the product ReFr*, regardless of impeller angle. This relationship, together with the Ga, specific for each fluid, allows scaling the results to other fluids such as molten pure aluminum. This study allows experimenting in simpler systems that involve transparent fluids, room temperature and low cost, to then elaborate a prediction of vortex height in fluids where measurements are difficult and costly, such as molten metals.  相似文献   
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