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971.
Robert J. Blanchard Stefano Parmigiani Christopher Bjornson Camlyn Masuda Scott M. Weiss D. Caroline Blanchard 《Aggressive behavior》1995,21(2):123-136
Swiss-Webster mice living in a visible burrow system (VBS) reacted to presentation of a live cat in the surface area of the VBS by retreat to the burrows and reductions in nondefensive behaviors such as eating and drinking. Live eat-exposed subjects remained in the burrows 14 hr or more, while subjects exposed to a toy (plush) cat prior to live cat exposure reemerged almost immediately and made many contacts with the toy cat. However, subjects exposed first to the cat and later to a toy cat showed intermediate surface reemergence times and cat contacts during toy cat tests, indicating strong sensitization effects of prior live cat exposure. Previous studies indicated that rats in this situation show retreat to the burrows, surface avoidance, and reduction in nondefensive behaviors. The mouse pattern was similar, with the notable exception that in the first 5min block after cat presentation, mice rapidly alternated retreat to the burrow chambers with reappearance in the tunnel segment near the surface, to scan the surface visually and sniff. Movement during this time block involved a stretch attend posture characteristic also of risk assessment activities in rats. Such visual and olfactory inspection of the cat is not seen in rats in the VBS. This difference may be related to the finding that rats, but not mice, emit ultrasonic “alarm cries” during and after cat exposure. © 1995 Wiley-Liss, Inc. 相似文献
972.
Power plants lose efficiency when the air preheater elements are not replaced or cleaned as they deteriorate. Replacing is more expensive than cleaning but more secure to preserve power and lifetime. How many baskets should be then replaced and how many cleaned to achieve ‘satisficing’ goals of cost, power and lifetime? We design deterministic/stochastic goal programming approaches to this problem and develop a decision case for usual preheaters. Some discrepancies in results between both approaches appear, the deterministic model advising to replace less baskets than the stochastic, which is plausible due to the risk variable. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
973.
Douglas A. Della Toffalo 《Journal of child and family studies》2000,9(3):351-361
Research on wraparound services has been generally positive, but has failed to include data regarding treatment integrity. Without such data, conclusions drawn from such studies are weakened. This study followed 28 children and adolescents receiving wraparound services in rural central Pennsylvania. Treatment integrity was defined as the percentage of service hours prescribed vs. received, and behavioral outcomes were defined as Total Problem Behavior T Scores on the Child Behavior Checklist. Preliminary analyses failed to reveal significant differences in sample means between included subjects and those excluded due to missing data. Outcome behavior ratings were significantly improved over baseline ratings. Regression analyses, however, failed to find a significant effect for treatment integrity when used in an outcome prediction equation for Therapeutic Support Staff, Mobile Therapy services, or Behavioral Specialist wraparound services. These results suggest that adherence to prescribed treatment hours may not be related to behavioral outcomes in a wraparound service setting. 相似文献
974.
临床试验中的利益冲突:伦理和政策问题 总被引:1,自引:0,他引:1
人们对于研究人员、赞助商和研究机构三者之间的经济利益关系给予越来越多的关注,人体试验研究中的经济利益与其他利益有所不同,这种经济利益会导致偏见或诱导不正当的行为,尤其是当有从研究中获益的机会存在时,将会影响到研究人员关于应该选择哪个受试者,应该提供给受试者什么样的医疗服务,甚至应该如何正确使用受试者保密的健康信息方面的判断,由经济利益引起的明显的风险同样也会威胁公众的学术机构研究使命的支持,从处理临床试验中利益冲突的准则,什么样的经济利益是研究中的重大经济利益。准则的实施等方面进行了详尽的叙述,最后指出没有潜在受试者和公众的信任,我们就不能有效地开展研究。 相似文献
975.
In this study we focus on the perception of one particular type of risk in the context of strategic alliances—relational risk. Perceived relational risk refers to the degree to which decision makers are concerned with the partner's opportunistic behavior in cooperative efforts. We develop a measure of relational risk in strategic alliances, and empirically examine some of its personal correlates. Based on a survey of senior executives of corporations and MBA students, we found partial support for the principal hypothesis that the perception of relational risk for prospective strategic alliances is related to an individual's age and trust in people. 相似文献
976.
自我框架、风险认知和风险选择 总被引:2,自引:1,他引:1
对行为决策中“框架效应”(Framing Effect)的研究进行了拓展:探讨了自我框架对风险决策的影响及其机制。面对运用图示方法表示的管理,健康,及投资方面的风险决策问题,参与者自主地选择对方案的描述(自我框架)。研究有四个主要发现:1)自我框架对风险选择的效应部分显著,而且对风险选择的影响方向因情境的不同而不同;2)机会威胁认知是自我框架效应的一个中介变量;3)自我框架在情绪语气上的差异对风险决策有显著影响:决策者对一个备选方案(确定性或风险性方案)相对于另一个备选方案的自我描述的情绪语气越积极正面,这个方案被选择的可能性越大;4)决策者的机会-威胁认知是这一自我框架效应的部分中介变量。也就是说,对备选方案的自我描述语气作为一种对决策信息的编码影响了风险(机会和威胁)认知,进而影响决策者的风险偏好和选择 相似文献
977.
978.
高技术的伦理风险及其应对 总被引:1,自引:0,他引:1
当代高技术的迅速崛起正日益改变世界,高技术的发展更增加了高技术伦理风险负效应的不确定性,既提供了更多的道德选择的可能性,又提出了严峻的挑战,进而使高技术的道德选择成为高技术活动主体不可回避的问题。为了在高技术的道德选择中尽可能减少高技术伦理风险负效应,就必须坚持必仁且智的价值取向、德得相通的运作方略、内圣外王的探究智慧,进而达到天人合一的澄明之境———使人-社会-自然系统协调发展。 相似文献
979.
Assessing confidence to resist drinking in high risk situations is an important part of behavioral treatments for alcohol problems. The present study assessed the reliability and validity of the original 100-item Situational Confidence Questionnaire (SCQ) and of an 8-item brief version (BSCQ). Using a visual analog scale, the BSCQ asked respondents to report their confidence to resist urges to drink heavily using the original eight SCQ subscales (e.g., pleasant times with others, social pressure). Data were collected from 120 adult problem drinkers who voluntarily entered an outpatient alcohol treatment program. The comparability of the BSCQ and the SCQ-100 was evaluated through intraclass correlations between the eight subscales and comparison of both instruments' underlying factor structures. Correlation coefficients for the subscales ranged from 0.56 to 0.80. Both instruments showed similar, but not identical factor structures. The present results indicate that the BSCQ provides comparable information to the SCQ-100. Limitations, as well as the clinical advantages, of using the BSCQ over longer versions are discussed. 相似文献
980.
Choice between constant and variable alternatives by rats: effects of different reinforcer amounts and energy budgets
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Two experiments, using rats as subjects, investigated the effect of different reinforcer amounts and energy budgets on choice between constant and variable alternatives under a closed economy. Rats were housed in the chamber and were exposed to a modified concurrent-chains schedule in which the choice phase was separated from a rest phase during which the rats could engage in other activities. In the choice phase, a single variable-interval schedule arranged entry into one of two equal terminal links (fixed-interval schedules). The constant terminal link ended with the delivery of a fixed number of food pellets (two or three, depending on the condition), whereas the variable terminal link ended with a variable number of food pellets (means of two or three, depending on the condition). Energy budget was defined as positive when body weights were over 90% of free-feeding weights, and as negative when they were under 80% of free-feeding weights. The different body weights were produced by varying the duration of the equal terminal-link schedules within daily 3-hr sessions. In Experiment 1, rats chose between a constant and a variable three pellets under both energy budgets. Rats preferred the constant three pellets more under the positive energy budget, whereas they were indifferent under the negative energy budget. In Experiment 2, rats chose between a constant three pellets and a variable two pellets, and chose between a constant two pellets and a variable three pellets under both energy budgets. The rats strongly preferred the constant three pellets over the variable two pellets under both energy budgets. In contrast, rats preferred the variable three pellets over the constant two pellets only under the negative energy budget, whereas they were indifferent under the positive energy budget. These results indicate that rats choices are sensitive to the difference in reinforcer amounts and to the energy budgets defined by the level of body weight. The present results are consistent with those obtained with small granivorous birds as well as with the predictions of a recent risk-sensitive foraging theory. 相似文献