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71.
The crane's foot: The rise of the pedigree in human genetics   总被引:1,自引:1,他引:0  
The standard pedigree used by geneticists is intimately connected to the history of genetics. Pedigrees drawn today are based on standards established in the early decades of the twentieth century. Those standards were established by geneticists who pursued an active interest in eugenics. The slightly different standards followed in America vs. England to some extent followed the stronger support of Mendelism by the Americans, as well as the individual preferences of the leading human geneticists in those countries.  相似文献   
72.
The substitutability of reinforcers   总被引:5,自引:3,他引:2       下载免费PDF全文
Substitutability is a construct borrowed from microeconomics that describes a continuum of possible interactions among the reinforcers in a given situation. Highly substitutable reinforcers, which occupy one end of the continuum, are readily traded for each other due to their functional similarity. Complementary reinforcers, at the other end of the continuum, tend to be consumed jointly in fairly rigid proportion, and therefore cannot be traded for one another except to achieve that proportion. At the center of the continuum are reinforcers that are independent with respect to each other; consumption of one has no influence on consumption of another. Psychological research and analyses in terms of substitutability employ standard operant conditioning paradigms in which humans and nonhumans choose between alternative reinforcers. The range of reinforcer interactions found in these studies is more readily accommodated and predicted when behavior-analytic models of choice consider issues of substitutability. New insights are gained into such areas as eating and drinking, electrical brain stimulation, temporal separation of choice alternatives, behavior therapy, drug use, and addictions. Moreover, the generalized matching law (Baum, 1974) gains greater explanatory power and comprehensiveness when measures of substitutability are included.  相似文献   
73.
This study investigated the effectiveness of using visual cues to highlight the seams of baseballs to improve the hitting of curveballs. Five undergraduate varsity baseball team candidates served as subjects. Behavior change was assessed through an alternating treatments design involving unmarked balls and two treatment conditions that included baseballs with 1/4-in. and 1/8-in. orange stripes marking the seams of the baseballs. Results indicated that subjects hit a greater percentage of marked than unmarked balls. These results suggest that the addition of visual cues may be a significant and beneficial technique to enhance hitting performance. Further research is suggested regarding the training procedures, effect of feedback, rate of fading cues, generalization to live pitching, and generalization to other types of pitches.  相似文献   
74.
Timeout from concurrent schedules.   总被引:1,自引:1,他引:0       下载免费PDF全文
Response-contingent timeouts of equal duration and frequency were added to both alternatives of unequal concurrent schedules of reinforcement. For each of 4 pigeons in Experiment 1, relative response rates generally became less extreme as the frequency of timeout increased. In Experiment 2, relative response rates consistently approached indifference as the duration of timeout was increased. Variation in time allocation was less consistent in both experiments. Absolute response rates did not vary with the timeout contingency in either experiment. In a third experiment, neither measure of choice varied systematically when the duration of a postreinforcement blackout was varied. In contrast to the present results, preference has been shown to vary directly with the parameters of shock delivery in related procedures. The pattern of results in the first two experiments follows that obtained with other manipulations of the overall rate of reinforcement in concurrent schedules. The results of the third experiment suggest that an intertrial interval following reinforcement is not a critical feature of the overall rate of reinforcement.  相似文献   
75.
The Nazi Holocaust has had continuing and widely reverberating consequences not only for the Jewish survivors but for the world at large. These consequences are detailed, first through a personal account of an Auschwitz survivor, and then through a discussion of the adaptive measures of concentration camp inmates and the long-term psychiatric and psychological effects on survivors and their families. The Survivor or Concentration Camp Syndrome and its relationship to the Post-Traumatic Stress Disorder is described. Indirect effects of the Holocaust have been manifested in various ways, particularly through various levels of psychologic denial displayed by Holocaust criminals and (at least during the early postwar period) by the German public. The Holocaust has had profound effects on the ways the Jewish people regard themselves and are seen by others. Finally, the Holocaust can be seen as offering a kind of paradigmatic signature to the worldview of the end of the 20th century, emphasizing the persistence of evil and the limitations of the idea of progress.  相似文献   
76.
In this paper, we examine the termination of children's mental health services. Analyses were based on the 901 families in the Fort Bragg Evaluation Project who participated at Wave 1 and Wave 2 six months later. The project compared a full continuum of care provided at a demonstration site with traditional care at two comparison sites. The results showed that in most cases families and providers were partners in decisions to terminate treatment. About half of the clients self-terminated or were terminated solely at the discretion of the provider. Providers tended to play a more dominant role in terminating restrictive services; families played a more central role in terminating outpatient care. Regardless of initial psychopathology, children in single-headed households, whose parents were dissatisfied with services, did not expect their child to cooperate with treatment and did not expect treatment to help their child, were more likely to terminate care than others. While the Demonstration site had significantly fewer terminations, the sites did not differ with regard to the reasons for termination, who participated in termination decisions, or the factors that affected the likelihood to terminate care. Of most interest, mental health outcomes among children who had terminated all care did not vary by reasons for termination or by who participated in the termination decision.  相似文献   
77.
The major challenge facing today’s biomedical researchers is the increasing competition for available funds. The competitive review process, through which the National Institutes of Health (NIH) awards grants, is built upon review by a committee of expert scientists. The NIH is firmly committed to ensuring that its peer review system is fair and objective. Wendy Baldwin, Ph.D., is Deputy Director for Extramural Research, National Institutes of Health. This paper is based on a presentation at a workshop, “Advances in Peer Review Research”, American Association for the Advancement of Science Meeting, Baltimore, MD, February 9, 1996.  相似文献   
78.
79.
This paper is a response to particularist critics of the normative force of moral principles. The particularist critique, as I understand it, is a rejection not only of principle-based accounts of moral deliberation and justification, but also of accounts of character in which principles play a central role. I focus on the latter challenge and counter it with a view I call character-principlism .
I begin by discussing in a general way what motivates the particularity objection to principles and then contrast two views – both of which insist on the importance of attentiveness to particularity – about the relative normative status of principles and particular cases. I present some reasons for believing that we need a more normatively robust conception of the role of moral principles than the particularists provide. In the main portion of the paper, I discuss how character-principlism sees principles functioning in our lives and the lives we lead with others. I contrast this with some other accounts of desirable character that particularists can embrace, and argue that these are seriously flawed because, unlike character-principlism, they cannot satisfactorily explain how a person could possess the constancy of character that moral integrity requires.  相似文献   
80.
Propositional and notional attitudes are construed as relations (-in-intension) between individuals and constructions (rather than propositrions etc,). The apparatus of transparent intensional logic (Tichy) is applied to derive two rules that make it possible to export existential quantifiers without conceiving attitudes as relations to expressions (sententialism).  相似文献   
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