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Lewis E. Gilbert 《Knowledge, Technology, and Policy》1998,11(1-2):4-15
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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John M. Pearce Helen Kaye Louis Collins 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1985,37(4):379-396
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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TIMOTHY F. MURPHY 《Journal of applied philosophy》1987,4(2):195-204
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
117.
Paul Dean 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1981,33(2):69-76
Behavioural evidence concerning short-sightedness in rats is apparently conflicting: in some experiments rats have performed poorly with visual stimuli further than about 60 cm distant, while in others they have made efficient use of more distant cues, for example to find their way through mazes. However, in the experiments suggesting short-sightedness, the physical size of the stimuli was not varied, so that stimulus distance and visual angle were confounded. In the present experiment, therefore, the size and distance of the stimuli to be detected were varied independently. Over the range tested (30-160 cm), distance was found to produce relatively slight effects on the smallest detectable visual angle, and these tended to diminish with practice. Thus, no good evidence was found for short-sightedness in rats up to 160 cm, a finding consistent with current views of the structure and image-forming capacities of the rat's eye. The smallest detectable targets were, however, surprisingly large in view of the rat's visual acuity (which is about 1c/deg): at the distances tested, animals required considerable training to run reliably to targets subtending less than 5-10° of visual angle. Difficulties in responding to stationary stimuli of this size are likely to restrict severely the use that rats make of vision both in the laboratory and in their natural surroundings. 相似文献
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