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141.
Racism as a stressor for African Americans. A biopsychosocial model.   总被引:30,自引:0,他引:30  
Various authors have noted that interethnic group and intraethnic group racism are significant stressors for many African Americans. As such, intergroup and intragroup racism may play a role in the high rates of morbidity and mortality in this population. Yet, although scientific examinations of the effects of stress have proliferated, few researchers have explored the psychological, social, and physiological effects of perceived racism among African Americans. The purpose of this article was to outline a biopsychosocial model for perceived racism as a guide for future research. The first section of this article provides a brief overview of how racism has been conceptualized in the scientific literature. The second section reviews research exploring the existence of intergroup and intragroup racism. A contextual model for systematic studies of the biopsychosocial effects of perceived racism is then presented, along with recommendations for future research.  相似文献   
142.
The role of the response-reinforcer relation in maintaining operant behavior under conditions of delayed reinforcement was investigated by using a two-operandum (i.e., two-key) procedure with pigeons. Responding on one key was reinforced under a tandem variable-interval differential-reinforcement-of-other-behavior (tandem VI DRO) schedule. The schedule defined a resetting unsignaled delay-of-reinforcement procedure in that a response was required when the interfood interval of the VI schedule lapsed, but further responding during the DRO component on either key reset the time interval. This ensured a fixed delay duration between any response and reinforcement. Responding on another key, physically identical to the first one except for spatial location, otherwise was without consequence. The location of the key correlated with the delay-of-reinforcement procedure varied between sessions according to a semirandom sequence. Differences in response rates between the two keys were greater, with proportionally higher rates on the key correlated with the delay-of-reinforcement procedure, the longer the delay-of-reinforcement procedure remained correlated with the same key. Differences in responding on the two keys also increased within individual sessions. These results suggest that the response-reinforcer relation is the primary determinant of responding when responding is acquired and maintained with delayed reinforcement.  相似文献   
143.
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   
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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   
146.
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   
147.
White SW  Kreiser NL  Pugliese C  Scarpa A 《Autism》2012,16(5):453-464
Problems with social anxiety are frequently reported in people with autism spectrum disorders (ASD). It is possible that social anxiety, when present, exacerbates the experience of hostility and other forms of aggression in relation to ASD symptoms. This study sought to determine if social anxiety symptoms mediate the relationship between features of ASD and feelings of hostility in young adults. Self-report measures of social anxiety, ASD, and facets of aggression were collected in a non-clinical sample (n = 618) of college students. Social anxiety was found to partially mediate the relationship between ASD features and self-reported hostility. There was also evidence for inconsistent mediation, such that social anxiety dampened the strength of the relationship between ASD symptoms and verbal and physical aggression. Findings highlight the potential influence of associated psychiatric symptoms in people with ASD. In addition, dimensional conceptualization of ASD symptoms, as opposed to a categorical approach solely, may be a useful approach to studying complex personality processes.  相似文献   
148.
This review of the literature examines the effect of contextual variables (i.e., characteristics of the perpetrator and victims, observer characteristics) on perceptions of physical and psychological aggression in close relationships. Observers view physical aggression as more serious, harmful, abusive, and more deserving of punishment than psychological aggression, male aggression as more serious than female aggression, and aggression in committed, exclusive relationships as more serious than aggression in casual ones. Victims of psychological aggression, however, perceive it as more harmful than physical aggression and consider the effects to be longer-lasting. The disparity between observer and victim perceptions of physical and psychological aggression extends to mental health professionals, who tend to judge the severity of aggressive behaviors based on frequency and duration of the actions instead of perpetrator intent. This difference of opinion may influence the reporting of and intervention in physically or psychologically aggressive situations, and how these types of aggression are treated by legal professionals, especially if those legal professionals are informed about aggressive romantic relationships by third-party observers whose opinions of the situation differ from those of the victims.  相似文献   
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