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101.
Male Siamese fighting fish, Betta splendens, swam through a ring in an aquarium, breaking a photocell beam and initiating an unsignaled, resetting delay interval. Following delays of 0 s, 10 s, or 25 s, a 15-s mirror presentation released an aggressive display by the fish. Swimming through the ring increased in the absence of either a period of acclimatization to the reinforcer (analogous to magazine training when appetitive reinforcers are used) or explicit training of the response by the experimenters. Response rates were a decreasing function of delay duration. Other fish exposed to a schedule of response-independent mirror presentations failed to acquire and maintain the response. The results demonstrate the robustness and generality of the phenomenon of response acquisition with delayed reinforcement. They further qualify earlier observations about behavioral mechanisms involved in the phenomenon.  相似文献   
102.
Abortion considerations require deep reflection on law, convention, social mores, religious norms, family contexts, emotions, and relationships. I have three arguments. First, a liberal “right to choose” framework is inadequate because it is based on individualist notions of rights. Second, reproductive freedoms should be extended to all women. Third, abortion ethics involves a dialectical interplay between rights and responsibilities, and between social, cultural, and particular contexts, and is best understood in terms of moral praxis.  相似文献   
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The importance of consulting with other professionals to maintain acceptable standards of care is well documented in many health care professions. However, evidence indicates that many psychologists fail to utilize consultation when needed, and that consultation use varies along dimensions such as the education and training of the consultee, the type of setting, number of years in practice, and proximity to available consultants. In this article, we review the research on the use of consultation by psychologists as well as other health care professionals. We discuss the clinical, ethical, and legal implications of seeking consultation as a professional psychologist. Finally, a detailed and practical model for the regular use of consultation is given to improve the routine use of consultation in clinical practice.  相似文献   
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现实论(actualism)这项方案,旨在清除逻辑与模态形而上学中那些讨人嫌的本体论承诺。它从一切存在的都是现实的这个观点出发,试图重新解释语言,以避免承诺“可能体”(possibilia)的存在。所谓“可能体”,指那些可能的,但非现实的对象。量化模态逻辑(QML)似乎就要求这种对象存在。最简QML为古典量化理论与模态命题逻辑之合并,可是它使巴康(Barcan)公式(今日x由→ax令Q)有效。从而,由可能存在一头会说话的驴子这个事实,就推出了存在某物,它可能是一头会说话的驴子。这看起来在宣称一个可能实体的存在(假定每个现实的东西都不可能是会说话的驴子)。现实论者们大力主张克里普克(Kripke)所描述的语义学,以此来免除这项承诺,这种语义学采用了可变论域,因而使巴康公式归于无效。  相似文献   
105.
今年1月10—15日俄罗斯科学院哲学所所长B.斯杰宾通讯院士、俄罗斯科学院哲学所高等研究员B.布罗夫来广东进行学术访问。1月12日在广东社联与省哲学界人士进行了座谈。会上,斯杰宾通讯院士就俄罗斯哲学的现状作了主要发言,并回答了与会者提出的一些问题,现将斯杰宾通讯院士的发言整理如下。  相似文献   
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University students participated in one of four standard two-choice signal-detection experiments in which signal presentation probability was varied and the reinforcement distribution was held constant and equal. In Experiments 1, 3 and 4, subjects' performance showed a systematic response bias for reporting the stimulus presented least often. Experiments 1 and 4 showed that this effect was reliable with extended training and monetary, rather than point, reinforcement. In Experiment 2, all correct responses were signaled in some way, and this produced the opposite relationship between signal presentation probability and response bias. Experiments 1 and 3 found that explicitly deducting money (intended as punishment) for equal numbers of incorrect responses on each alternative, or varying the obtained overall rate of reinforcement, produced no clear change in response bias. The bias, shown by humans, for reporting the stimulus presented least often remains a challenge for theories of stimulus detection.  相似文献   
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