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排序方式: 共有264条查询结果,搜索用时 15 毫秒
41.
Helene Guis Cyril Caminade Carlos Calvete Andrew P. Morse Annelise Tran Matthew Baylis 《Journal of the Royal Society Interface》2012,9(67):339-350
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
42.
This report describes a rapid solid-phase melting curve analysis method for single-nucleotide polymorphism (SNP) genotyping. The melting curve analysis is based on dynamic allele-specific hybridization (DASH). The DNA duplexes are conjugated on beads that are immobilized on the surface of a microheater chip with integrated heaters and temperature sensors. SNP on PCR products were scored, illustrating the sensitivity and robustness of the system. The method is based on random bead immobilization by microcontact printing. Single-bead detection and multiplexing were performed with a heating rate more than 20 times faster than conventional DASH. Analyses that took more than 15 min could be performed in less that 1 min, enabling ultrarapid SNP analysis. In addition, an array version of the chip was implemented enabling the preparation of an array of bead arrays for high-throughput and rapid SNP genotyping. 相似文献
43.
O. Helene 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1997,390(3):1125-387
This paper discusses how to combine different experimental results in order to obtain upper or lower limits of physical quantities in the case of null experiments. Reanalyzing some published results, half-life limits for p → e+π0, p →
K+, and for the 76Ge ββ(0ν)-decay to the ground state of 76Se were determined as 5.7 × 1032, 1.4 × 1032 and 2.5 × 1024 yr, respectively, at 90% Confidence Level. The Bayesian approach is adopted using a step function as the prior-probability density function of the decay constant. 相似文献
44.
Fung Helene H.; Lu Alice Y.; Goren Deborah; Isaacowitz Derek M.; Wadlinger Heather A.; Wilson Hugh R. 《Canadian Metallurgical Quarterly》2008,23(2):440
Socioemotional selectivity theory postulates that with age, people are motivated to derive emotional meaning from life, leading them to pay more attention to positive relative to negative/neutral stimuli. The authors argue that cultures that differ in what they consider to be emotionally meaningful may show this preference to different extents. Using eye-tracking techniques, the authors compared visual attention toward emotional (happy, fearful, sad, and angry) and neutral facial expressions among 46 younger and 57 older Hong Kong Chinese. In contrast to prior Western findings, older but not younger Chinese looked away from happy facial expressions, suggesting that they do not show attentional preferences toward positive stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
How rapidly does boundary extension occur? Across experiments, trials included a 3-scene sequence (325 ms/picture), masked interval, and repetition of 1 scene. The repetition was the same view or differed (more close-up or wide angle). Observers rated the repetition as same as, closer than, or more wide angle than the original view on a 5-point scale. Masked intervals were 100, 250, 625, or 1,000 ms in Experiment 1 and 42, 100, or 250 ms in Experiments 2 and 3. Boundary extension occurred in all cases: Identical views were rated as too "close-up," and distractor views elicited the rating asymmetry typical of boundary extension (wider angle distractors were rated as being more similar to the original than were closer up distractors). Most important, boundary extension was evident when only a 42-ms mask separated the original and test views. Experiments 1 and 3 included conditions eliciting a gaze shift prior to the rating test; this did not eliminate boundary extension. Results show that boundary extension is available soon enough and is robust enough to play an on-line role in view integration, perhaps supporting incorporation of views within a larger spatial framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Raskin White Helene; Bates Marsha E.; Buyske Steven 《Canadian Metallurgical Quarterly》2001,110(4):600
The authors examined how neuropsychological, personality, and environmental risk factors and their interactions were related to trajectories of delinquent behavior from adolescence to adulthood. Four waves of longitudinal data from 698 male participants, ages 12–18 at Time 1 and ages 25–31 at Time 4, were included in the analyses. Using a growth mixture model approach, 4 trajectories were identified: nondelinquents, adolescence-limited delinquents, adolescence-to-adulthood-persistent delinquents, and escalating delinquents. Five risk factors distinguished escalating from persistent delinquents and 5 also distinguished nondelinquents from the 3 delinquency trajectories. Persistent delinquents scored significantly higher than adolescence-limited delinquents on only one risk factor, disinhibition. Overall, few of the factors that are related to childhood-to-adolescence persistence were associated with persistence in delinquency beyond adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Sending memorable messages to the old: Age differences in preferences and memory for advertisements.
Socioemotional selectivity theory holds that people of different ages prioritize different types of goals. As people age and increasingly perceive time as finite, they attach greater importance to goals that are emotionally meaningful. Because the goals that people pursue so centrally influence cognition, the authors hypothesize that persuasive messages, specifically advertisements, would be preferred and better remembered by older adults when they promise to help realize emotionally meaningful goals, whereas younger adults would not show this bias. The authors also predict that modifying time perspective would reduce age differences. Findings provide qualified support for each of these predictions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
This brief report examined how the likelihood of destructive anger responses varied with age across relationship contexts. Seventy-six older adults and 100 younger adults from Hong Kong and Mainland China reported their responses to anger-eliciting scenarios elicited by a kin, a close or a casual friend. Results indicated that compared with their younger counterparts, older Hong Kong Chinese were less likely to report direct aggression toward kin, but older Mainland Chinese were more likely to do so. Older Hong Kong Chinese were less likely to report malevolent and fractious motives than were younger Chinese across all relationships; Older Mainland Chinese were less likely to do so only in friendship. Findings have implications for conceptualizing age-related emotion regulation across relationships and cultures. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
49.
Matthias Fromm Helene M. Loos Sandra Bayha Reinhold Carle Dietmar R. Kammerer 《Food chemistry》2013,136(3-4):1277-1287
The aim of this study was to investigate whether complexly constituted phenolic extracts from apple seeds may be utilised for the recovery of natural coloured antioxidant preparations, which might serve as potential food or cosmetic ingredients.In a first step, the recovery of phenolic compounds was optimised by varying crucial extraction parameters. A single extraction step at 25 °C using an acetone–water mixture (60:40, v/v) and a solid-to-solvent ratio of 1:8 (w/v) for 1 h was found to be appropriate to achieve both high phenolic yields and antioxidant activities.In a second step, differently produced apple seed extracts and a phloridzin model solution were enzymatically treated by mushroom polyphenol oxidase to investigate the rate of pigment synthesis. Depending on the extraction procedure applied, synthesis rates, pigment yields and colour properties significantly differed. Compared to the phloridzin model solution, extracts recovered from the seeds showed comparable and even better results, thus indicating such preparations to be a promising alternative to synthetic yellow dyes. 相似文献
50.
In order to draw conclusions concerning the sound velocity and the dynamic modulus of elasticity of logs and green timber at reference conditions, properties were determined for green timber at temperatures around and below the freezing point. The present investigation includes the analysis of the dependence of sound velocity and dynamic modulus on temperatures between ?20?°C and +20?°C and on moisture contents below and above fibre saturation. Sound velocity and dynamic modulus of elasticity were determined based on natural frequency and density. Both sound velocity and dynamic MOE decreased linearly with increasing moisture content and increasing temperature below fibre saturation. Three temperature areas need to be considered above fiber saturation—below ?5?°C and above 0?°C and the area between ?5?°C and 0?°C. Sound velocity as well as dynamic MOE decrease linearly with increasing temperature. Based on these findings, appropriate adjustment functions for each moisture content and temperature range were found to calculate the dynamic properties at the reference conditions. 相似文献