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221.
Preference after training with differential changeover delays   总被引:3,自引:3,他引:0       下载免费PDF全文
Pigeons were trained on a multiple schedule in which each component consisted of concurrent variable-interval (VI) 30-s VI 60-s schedules. The two components of the multiple schedule differed only in terms of the changeover delays (COD): For one component short CODs were employed, and in the second component long CODs were used. After approximate matching was obtained in each component, probe tests involving new combinations of stimuli were presented (e.g., the VI 30-s schedule from each component) to determine how the different CODs affected preference. Despite shorter CODs producing higher changeover rates, the COD value had no systematic effect on preference on the probe trials. However, differences in reinforcement rate always produced preference for the schedule with the higher reinforcement rate. The results thus show that the the pattern of changeover behavior per se is not a critical determinant of choice in the probe-trial procedure.  相似文献   
222.
Menopause is a normative life transition that is experienced by virtually all women, yet remains poorly understood. The dominance of the biomedical model results in a unidimensional definition of menopause as a biological event, ignoring the influence of cultural and psychosocial factors. Counselors who use an integrative approach can not only provide accurate biomedical information but also conceptualize menopause as a normative midlife transition. The purpose of this article is to provide a foundation in biomedical issues and to consider how these independently, and in interaction with cultural and psychosocial factors, influence the experience of menopause.  相似文献   
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Recent sociological analyses of the intersections of race and science recognise race’s quality as an enacted object. Through this analytic lens, race is always materialising in the practices and processes that enrol it and therefore enjoys a kind of multiplicity. The context of blood stem cell transplantation, a scientific domain marked by a more and less explicitly racialised logic, offers an opportunity to see the conceptual assertion of race’s multiplicity play out. Indeed, an exploration of the UK’s stem cell inventory reveals—through analysis of interviews, policy and parliamentary meetings—how race materialises in the various practices that comprise this increasingly popular cancer treatment option. Looking at practices of recruitment, inventory management and tissue selection in particular provides an interesting window to look upon race and the many signifiers that implicate it. These cases reveal moments of race’s stablisation and silencing; its oscillation between the status of vital information to the life of a public stem cell inventory, and of secondary data that provides little useful information to clinicians selecting tissue. Adopting an analytic lens that attends to race’s multiple enactments allows us to begin asking why enactments take the shape they do, and why the particular practices that mobilise them come to be.  相似文献   
226.
This study examines perceived stress and its relationship to depressive symptoms, life changes and functional capacity in a large sample of individuals who are positive for the Huntington disease (HD) gene expansion but not yet diagnosed. Participants were classified by estimated proximity to HD diagnosis (far, mid, near) and compared with a non-gene-expanded comparison group. Persons in the mid group had the highest stress scores. A significant interaction between age and time since HD genetic testing was also found. Secondary analyses using data from a different data collection point and including a diagnosed group showed the highest stress scores in the diagnosed group. Possible explanations and implications are discussed.  相似文献   
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We propose a model to measure risk in a prisoner's dilemma based on Coombs' (1973) re‐parameterization of the game as an individual risk decision‐making task that chooses between a gamble of cooperation and another gamble of defection. Specifically, we propose an index, r, to represent the risk associated with cooperation relative to defection. In conjunction with Rapoport's (1967) index of cooperation (K), our formulation of risk allows us to construct games that vary in risk (as indexed by r) while controlling for cooperativeness (as indexed by K). Following utility analysis that models risk seeking as a convex utility function and risk averse as a concave function, we predict that risk‐seeking people cooperate more in games that the cooperation choice is more risky, whereas risk‐averse people cooperate more in games that the cooperation choice is less risky. In the three studies that we varied game parameters, used different measures of risk orientation and prosocial orientation and used different experimental procedures, we found robust results supporting our predictions. Theoretical analysis of our formulation further suggests that risk and cooperativeness of a prisoner's dilemma game is not entirely independent. Games that have a higher cooperativeness index are necessarily more risky. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Force and Freedom insists that, ‘Freedom, understood as independence of another person's choice, is [all] that matters’. In this paper I suggest that this premise leads Ripstein to an instrumentalization of democracy that neglects a properly public and collective notion of freedom. The paper first criticizes Ripstein's key argument against any extension of public purposes beyond the upholding of persons’ ‘independence of others’ choice’. More constructively, the paper then suggests that a space of public freedom is opened up when people deliberate in order to form and pursue democratic purposes. Citizens may act together to promote ends that they think are worthwhile, without dominating one another or restricting individual freedom.  相似文献   
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The authors examine the history and development of the counseling profession in Kenya. This profession is deeply rooted in responses to the HIV/AIDS epidemic, the emergence of mental health needs created by the impact of political and community‐based violence, increasing student unrest in public institutions, and government efforts to provide social–emotional support for students in public schools and universities. The authors also examine the challenges for the profession and make recommendations for the future.  相似文献   
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Research shows that reflecting on benefits received can make people happier, but it is unclear whether or not such reflection makes them more helpful. Receiving benefits can promote prosocial behavior through reciprocity and positive affect, but these effects are often relationship-specific, short-lived, and complicated by ambivalent reactions. We propose that prosocial behavior is more likely when people reflect on being a benefactor to others, rather than a beneficiary. The experience of giving benefits may encourage prosocial behavior by increasing the salience and strength of one's identity as a capable, caring contributor. In field and laboratory experiments, we found that participants who reflected about giving benefits voluntarily contributed more time to their university, and were more likely to donate money to natural-disaster victims, than were participants who reflected about receiving benefits. When it comes to reflection, giving may be more powerful than receiving as a driver of prosocial behavior.  相似文献   
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