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111.
The ability of two species of tits to remember the location and/or features of an object was tested in a delayed-matching-to-sample procedure. Three values of retention interval between presentation of the sample stimulus and the choice--30 sec, 5 min, and 15 min--were used. Both species performed at above-chance level at all retention intervals, and there was no significant decline in accuracy with increasing interval. A pool of 100 stimulus objects was used, but the results of control trials indicated that the birds responded primarily to location rather than stimulus features of the object itseif. Although the food-storing marsh tit tended to perform at a higher level than the non-storing great tit, the only significant difference between the species was in the first 50 trials of the first treatment, when the birds were acquiring the task. The results are discussed in relation to the hypothesized special memory capacity of food-storing birds.  相似文献   
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As the complexity of the challenges presented by our interactions with our planet continues to grow, we must develop new modes of knowledge production. In these modes, distinctions between multidisciplinary and inter-disciplinary activities and processes have renewed importance. There are at least two distinct types of interdisciplinary activities distinguished by the disciplinary breadth they attempt to bridge. In the narrow case, reductionist processes reveal a common underlying principle or process which can serve as a Rosetta stone. In the broad case, no such common arbiter exists. Investigators must develop integrating vocabulary in the context of the full breadth of their work. His primary activities are the fostering of university-wide interdisciplinary research and curriculum programs focused on global change with the goal of developing Columbia into a world leader in issues related to global stewardship.  相似文献   
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Three experiments, each using a single group of pigeons, are reported. In Experiment 1 subjects were initially trained with two stimuli, one of which was always followed by food, the other being reinforced according to a 50% partial reinforcement schedule. Subsequently a serial procedure was adopted in which an additional stimulus, C, was consistently followed by the partially reinforced CS. A second additional stimulus, A, was followed on half of its occurrences by the continuously reinforced CS, its remaining presentations being followed by nothing. The rate of autoshaped keypecking was substantially greater during A than during C. In the remaining experiments subjects received first-order conditioning with a single stimulus that was either partially (Experiment 2) or continuously (Experiment 3) reinforced. The stimuli A and C were then again introduced for serial autoshaping. Stimulus A was occasionally paired with the CS and occasionally followed by nothing, whereas stimulus C was always followed by the CS. As in Experiment 1, the rate of responding during A was greater than during C. It is proposed that one influence on the rate of autoshaped keypecking during a CS is the accuracy with which the immediate consequences of that CS are predicted.  相似文献   
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A child's adjustment to wartime stress is reliant not only on individual responses and qualities, but very significantly on the availability of support that they may receive from their parent or caregivers and quality of relationships. Strengthening parental support has the potential to be valuable. A pilot two-arm randomised controlled trial investigated the feasibility of delivering and evaluating the “Caring for Children Through Conflict and Displacement” intervention with caregivers in the West Bank. Feasibility to recruit and train non-specialist staff on-the-ground to screen families for eligibility, collect outcome data, deliver the intervention and to recruit and retain families in the study were examined. Research staff and intervention facilitators were successfully appointed in the field, screened participants and delivered the intervention to 120 caregivers, collecting outcome measures pre-and post-delivery. All families completed the outcome measures, with very little missing data. This indicated that the intervention can be delivered feasibly and evaluated with families in this humanitarian context. Preliminary outcome data showed promise that the intervention may have the potential to both improve family functioning and reduce children's problem behaviour. Implications of family-focused initiatives, particularly within a conflict/post-conflict context for the prevention of several negative health and social outcomes directions, are discussed.  相似文献   
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ABSTRACT In this essay the argument set forth by Michael Levin regarding the abnormality of homosexual behaviour is reviewed and criticized. Against his argument which holds that homosexual behaviour is abnormal because it constitutes an evolutionary aberration, I argue that Levin's and all similarly constructed arguments fail to show that evolutionary origins of sexual behaviour have any significant normative force. I contend that his notion of homosexuality is confused and that he fails to consider alternative methods of how homosexuality might have indeed served evolutionary adaptive purposes or been the result of surplus adaptations. I argue, too, that Levin's linking of unhappiness with homosexual behaviour is spurious and ill-supported. Consequently, I reject Levin's claims that public policy ought to do what it can to minimize the incidence of such behaviour. I argue by contrast that if happiness is the end of public policy decisions, then society ought to take what measures it can to protect persons in respect of their homosexual behaviour and identities.  相似文献   
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