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1.
Vector-borne diseases are among those most sensitive to climate because the ecology of vectors and the development rate of pathogens within them are highly dependent on environmental conditions. Bluetongue (BT), a recently emerged arboviral disease of ruminants in Europe, is often cited as an illustration of climate''s impact on disease emergence, although no study has yet tested this association. Here, we develop a framework to quantitatively evaluate the effects of climate on BT''s emergence in Europe by integrating high-resolution climate observations and model simulations within a mechanistic model of BT transmission risk. We demonstrate that a climate-driven model explains, in both space and time, many aspects of BT''s recent emergence and spread, including the 2006 BT outbreak in northwest Europe which occurred in the year of highest projected risk since at least 1960. Furthermore, the model provides mechanistic insight into BT''s emergence, suggesting that the drivers of emergence across Europe differ between the South and the North. Driven by simulated future climate from an ensemble of 11 regional climate models, the model projects increase in the future risk of BT emergence across most of Europe with uncertainty in rate but not in trend. The framework described here is adaptable and applicable to other diseases, where the link between climate and disease transmission risk can be quantified, permitting the evaluation of scale and uncertainty in climate change''s impact on the future of such diseases.  相似文献   
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The Asian tiger mosquito (Aedes albopictus) is an invasive species that has the potential to transmit infectious diseases such as dengue and chikungunya fever. Using high-resolution observations and regional climate model scenarios for the future, we investigated the suitability of Europe for A. albopictus using both recent climate and future climate conditions. The results show that southern France, northern Italy, the northern coast of Spain, the eastern coast of the Adriatic Sea and western Turkey were climatically suitable areas for the establishment of the mosquito during the 1960–1980s. Over the last two decades, climate conditions have become more suitable for the mosquito over central northwestern Europe (Benelux, western Germany) and the Balkans, while they have become less suitable over southern Spain. Similar trends are likely in the future, with an increased risk simulated over northern Europe and slightly decreased risk over southern Europe. These distribution shifts are related to wetter and warmer conditions favouring the overwintering of A. albopictus in the north, and drier and warmer summers that might limit its southward expansion.  相似文献   
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To date, the survival of Escherichia coli O157:H7 and other verocytotoxin-producing E. coli (VTEC) in chocolate and other confectionery products has not been fully established, unlike Salmonella, which have been responsible for occasional outbreaks of infection linked to contaminated chocolate and related products, although none of these outbreaks have been related to products produced in the United Kingdom. The United Kingdom Biscuit, Cake, Chocolate and Confectionery Alliance commissioned this study to obtain information on the decline and potential survival of E. coli, particularly verocytotoxin-producing strains, in reduced aw confectionery products chocolate, biscuit cream and mallow. These products were artificially contaminated with high (4 log10 cfu/g) and low (2 log10 cfu/g) levels of E. coli O157:H7, O111:H- and O26:H11 and their survival, as affected by storage temperature (10, 22 and 38 degrees C), was monitored over 12 months. Preliminary studies to establish the best inoculation and recovery procedures indicated that differences between counts on selective and non-selective media used were not sufficiently different to influence the outcome of this study. Irrespective of sample type, rapid decline was observed in products stored at 38 degrees C and increased survival occurred in products stored at 10 degrees C. In chocolate (average aw 0.40), these bacteria were detected for up to 43 days in samples stored at 38 degrees C. At 22 degrees C they survived for up to 90 days and in product stored at 10 degrees C they could still be detected after 366 days storage. In biscuit cream (average aw 0.75) they survived for 2 days at 38 degrees C, 42 days at 22 degrees C and 58 days at 10 degrees C. Whilst mallow (aw ca. 0.73) was not stored at 38 degrees C, these bacteria could still be detected in samples stored for up to 113 and 273 days at 22 and 10 degrees C, respectively. The observed prolonged survival of these bacteria under conditions of reduced aw and lowered storage temperature in this study is supported by previous studies with Salmonella and E. coli O157:H7 in other foods. In the same way that Salmonella bacteria can survive for long periods, in excess of 12 months, in chocolate, this study provides evidence that E. coli, including pathogenic strains, can also survive for similar periods of time. Assuming the routes of transmission are similar, controls currently used by the confectionery industry to prevent contamination by Salmonella should also be effective against E. coli, including VT-producing strains, providing that all raw materials have been suitably processed, stored and handled before and during manufacture.  相似文献   
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Monkeys with lesions to the hippocampus and overlying cortex were impaired in making a spatially selective response on the basis of a spatial cue. Their impairment was even more severe on a task in which they were required to make spatial responses on the basis of cues which are not spatially distinct. A second experiment showed that once lesioned monkeys had been trained on a task with spatially distinct stimuli, they were initially able to perform accurately if the aspatial distinctiveness of the cue was reduced. However, their performance declined to chance over four to six trials. These results suggest that lesions to the hippocampus and overlying cortex may cause impairments in memory for the arrangement of visual scenes, including the spatial location of responses. Keywords: spiny neurons, direct pathway, indirect pathways, rat neostriatum  相似文献   
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A new algorithm is presented for solving nonlinear second-order coupled differential equations of the form y′ = F(x,y). Modifications of the standard Numerov procedure have resulted in a rapid, noniterative, predictor-corrector form without matrix inversion and with improved accuracy. Comparisons with the usual Numerov and de Vogelaere methods are presented for the homogeneous case F(x,y) = -G(x)y often encountered in quantum scattering theory. Tests are also presented of a version with variable step size and with stabilization by orthogonalization of the solutions at internally determined. intervals.  相似文献   
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Product family design offers a cost-effective solution for providing a variety of products to meet the needs of diverse markets. At the beginning of product family design, designers must decide what can be shared among the product variants in a family. Optimal design formulations have been developed by researchers to find one optimal component sharing solution based on commonality, cost or technical performance of a product family. However, these optimization methods may not be able to apply in consumer product design because some metrics (e.g., visual appeal and ergonomics) of a consumer product cannot be formulized. In this paper, we suggest a tradeoff between commonality and the quality of the modular architecture in product family platform selection. We introduce a method for designers to identify multiple component sharing options that lie along a Pareto front of maximum commonality and strategic modularity. The component sharing options along the Pareto front can be evaluated, compared, and further modified. We demonstrate the method using a case study of product family platform selection of high-end and low-end impact drivers and electric drills. In the case study, the quality of the modular architecture is evaluated using a design structure matrix (DSM) for each of product variants. Three architectures along the Pareto front with maximum commonality, optimal modularity, and a balanced solution of the two metrics are highlighted and further examined to validate the effectiveness of our method.  相似文献   
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A cross-sectional assessment of differences in social class and other sociodemographic variables at hospital admission for patients with psychotic disorders was carried out through a systematic survey of psychotic patients admitted to greater Baltimore psychiatric facilities between 1983 and 1989. Female patients, first-admission patients, and patients with bipolar disorder or other, nonschizophrenic psychosis were more likely to have been admitted to community, university, and private hospitals than to state hospitals. Patients in medium and higher social class categories were 1.29 to 2.57 times more likely to be admitted to community, university, and private hospitals than to state hospitals.  相似文献   
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Most studies of selective attention briefly present static 2-dimensional stimuli and require arbitrary responses such as verbal naming or a keypress. Many of perceptual-motor interactions with the environment, however, require reaching directly toward an object while ignoring other objects in the scene. A series of experiments examines selective attention in the latter reaching situation. Effects previously observed in the traditional experimental procedures were obtained, suggesting that the models developed (which propose inhibitory mechanisms, for example) apply to ecologically valid situations. Attention accesses action-centered internal representations during such tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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