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131.
132.
An essential element of goal-directed decision-making in social contexts is that agents'' actions may be mutually interdependent. However, the most well-developed approaches to such strategic interactions, based on the Nash equilibrium concept in game theory, are sometimes too broad and at other times ‘overlook’ good solutions to fundamental social dilemmas and coordination problems. The authors propose a new theory of social decision-making—virtual bargaining—in which individuals decide among a set of moves on the basis of what they would agree to do if they could openly bargain. The core principles of a formal account are outlined (vis-à-vis the notions of ‘feasible agreement’ and explicit negotiation) and further illustrated with the introduction of a new game, dubbed the ‘Boobytrap game’ (a modification on the canonical Prisoner''s Dilemma paradigm). In the first empirical data of how individuals play the Boobytrap game, participants'' experimental choices accord well with a virtual bargaining perspective, but do not match predictions from a standard Nash account. Alternative frameworks are discussed, with specific empirical tests between these and virtual bargaining identified as future research directions. Lastly, it is proposed that virtual bargaining underpins a vast range of human activities, from social decision-making to joint action and communication.  相似文献   
133.
Understanding sensory systems that perceive environmental inputs and neural circuits that select appropriate motor outputs is essential for studying how organisms modulate behavior and make decisions necessary for survival. Drosophila melanogaster oviposition is one such important behavior, in which females evaluate their environment and choose to lay eggs on substrates they may find aversive in other contexts. We employed neurogenetic techniques to characterize neurons that influence the choice between repulsive positional and attractive egg-laying responses toward the bitter-tasting compound lobeline. Surprisingly, we found that neurons expressing Gr66a, a gustatory receptor normally involved in avoidance behaviors, receive input for both attractive and aversive preferences. We hypothesized that these opposing responses may result from activation of distinct Gr66a-expressing neurons. Using tissue-specific rescue experiments, we found that Gr66a-expressing neurons on the legs mediate positional aversion. In contrast, pharyngeal taste cells mediate the egg-laying attraction to lobeline, as determined by analysis of mosaic flies in which subsets of Gr66a neurons were silenced. Finally, inactivating mushroom body neurons disrupted both aversive and attractive responses, suggesting that this brain structure is a candidate integration center for decision-making during Drosophila oviposition. We thus define sensory and central neurons critical to the process by which flies decide where to lay an egg. Furthermore, our findings provide insights into the complex nature of gustatory perception in Drosophila. We show that tissue-specific activation of bitter-sensing Gr66a neurons provides one mechanism by which the gustatory system differentially encodes aversive and attractive responses, allowing the female fly to modulate her behavior in a context-dependent manner.  相似文献   
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135.
A hot environment combined with physically demanding tasks can subject workers to a higher risk of heat stress. A series of regulations and guidelines have been proposed to design appropriate anti-heat stress work uniform to reduce body heat strain. The present study aimed to examine heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion in the heat. 10 healthy males performed intermittent treadmill running/walking to exhaustion, followed by 30 min passive recovery sitting in a climatic chamber, which simulated the hot and humid outdoor environment (34 °C temperature, 60% relative humidity, 0.3 m/s air velocity, and 450 W/m2 solar radiation). The participants took part in five wear trials in counter-balanced order, including Sportswear, CIC Uniform, NEW Uniform, ICEBANK Cooling Vest, and NEW Cooling Vest, which have different levels of cooling capacity. Core temperature, skin temperature, heart rate, sweat loss, ratings of perceived exertion, and thermal sensations were measured throughout the entire heat exposure period. Physiological heat strain indices, including the physiological strain index (PhSI) and the perceptual strain index (PeSI), were used as a yardstick to quantify and compare the rate of recovery. Significantly lower physiological strain was observed in the newly developed NEW Uniform and NEW Cooling Vest groups compared with the commonly worn CIC Uniform group during recovery. At the end of the recovery period, participants in NEW Cooling Vest achieved the highest recovery (42.18% in PhSI and 81.08% in PeSI), followed by ICEBANK Cooling Vest, Sportswear, NEW Uniform, and CIC Uniform. The cooling capacity of anti-heat stress clothing ensembles and the recovery time significantly affect the rate of recovery in PhSI and PeSI, which may benefit the industry by formulating the appropriate work–rest schedule by considering the clothing effect.  相似文献   
136.
1 Introduction The visual world is composed of complex visual scenes that are projected, as two-dimen- sional images, onto the retina. Chunking of visual information is critical for object recognition, because it produces primitive perceptual units for subsequent analyses[1]. Integration of discrete local elements into a global configuration is one of the functions of perceptual grouping (e.g., combining local rectangles into a global letter as shown in fig. 1(b)). When multiple global object…  相似文献   
137.
郑跃玲 《菌物研究》2004,2(2):38-41
应用模糊数学对 7个平菇品种进行模糊判决 ,结果表明 :在权重偏重于生物学效率的凸模糊判决中平菇 17- 2为首选。而在权重相等的模糊判决中平菇 99号为首选。对平菇 99号进行综合评判的结果为某类菇农对该品种很喜欢。  相似文献   
138.
The purpose of this study is to test whether the integration of past and present foraging experience in web relocation decision enhances foraging efficiency of the spider Cyclosa argenteoalba in its natural environment. We measured daily changes in the prey availability at several fixed sites in a natural environment and constructed a model environment based on these observational data. In the model environment, we simulated the behavior of spiders that foraged and relocated their webs according to several decision rules, which differed in terms of how a spider used its past experience. Results of the simulation revealed that the less past experience is discounted in making web relocation decisions, the more prey the spider is expected to capture. The expected number of web relocations decreased as spiders kept past foraging experience longer. These results suggest that C. argenteoalba enhances foraging efficiency by using past foraging experience for long times in the decision of web relocation in its natural environment.  相似文献   
139.
斜纹夜蛾药剂防治综合决策的研究   总被引:2,自引:2,他引:0  
根据不同药剂对斜纹夜蛾的防治效果、防治工本费、对天敌的影响、防治后挽回的产量损失等资料,以净收益最大作为最优防治目标,运用优化理论和多目标决策方法,对11种药剂防治措施进行了综合分析。结果表明,在11种药剂防治措施中,以每667m^2施1.8%阿维菌素乳油16.7ml最优,其次是1.8%阿维菌素乳油25ml,20%氰戊菊酯乳油25ml,2.5%功夫乳油16.7ml,2.5%功夫乳油25ml,20%氰戊菊酯乳油50ml,4.5%高效氯氰菊酯乳油50ml,4.5%高效氯氰菊酯乳油25ml,50%辛硫磷乳油50ml,10%除尽悬浮剂16.7ml,10%除尽悬浮剂25ml,为合理地选择农药和用量提供了科学依据。  相似文献   
140.
构建我国生物多样性评价的指标体系   总被引:4,自引:0,他引:4  
生物多样性指标体系的建设过程长期而复杂,需要结合科学研究、监测以及决策制定,并基于合理的结构进行指标设计.构建适宜的生物多样性评价指标体系、监测评估生物多样性状况及变化趋势,已被纳入我国国家生物多样性战略及其行动计划.本文结合国内外经验,从指标的逻辑框架、空间尺度、时间尺度、指标类型、评价方法等5个方面探讨了指标体系构...  相似文献   
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