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Rats' lever presses on a retractable lever earned brief presentations of discriminative stimuli signalling periods in which responding on an alternative lever was either non-reinforced (extinction) or reinforced on a random ratio schedule. The predictions of two theoretical accounts of this behaviour were tested by studying the effects of omitting either the stimulus signalling the reinforced or that signalling the non-reinforced schedule component. Under these conditions rats' behaviour is determined by the conditioned, affective properties of the stimuli rather than by their purely informational properties.  相似文献   
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Reducing STDs and HIV/AIDS incidence requires campaigns designed to change knowledge, attitudes, and practices of risky sexual behavior. In China, a significant obstacle to such changes is the stigma associated with these diseases. Thus 1 campaign intervention strategy is to train credible community leaders to discuss these issues in everyday social venues. This study tested the effectiveness of such an approach on reducing HIV/AIDS stigma, across 2 years, from a sample of over 4,500 market vendors, in 3 conditions. Results showed an increasing growth in market communication about intervention messages, and concomitant declines in stigmatizing attitudes, across time, with the greatest changes in community popular opinion leaders, significant changes in intervention nonopinion leaders, and little change in the control markets.  相似文献   
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OBJECTIVE: To examine dysregulation in biological measures associated with histories of abuse in women and whether women with premenstrual dysphoric disorder (PMDD) differ in their dysregulation. DESIGN: Twenty-five women meeting prospective criteria for PMDD and 42 non-PMDD controls underwent structured interview to determine abuse histories and lifetime Axis I diagnoses, excluding those with current Axis I disorders or using medications. MAJOR OUTCOME MEASURES: Plasma cortisol and norepinephrine (NE), heart rate (HR), blood pressure (BP), and vascular resistance index (VRI) were assessed at rest and in response to mental stress. RESULTS: A greater proportion of PMDD women had prior abuse compared with non-PMDD women. Regardless of PMDD status, all abused women had lower plasma NE and higher HRs and tended to have lower plasma cortisol at rest and during stress. Abused women also reported more severe daily emotional and physical symptoms. Greater VRI and BP at rest and during stress were seen only in PMDD women with abuse. CONCLUSION: There is persistent dysregulation in stress-responsive systems in all abused women that cannot be accounted for by current psychiatric illness or medications, and PMDD women may be differentially more vulnerable to the impact of abuse on measures reflecting alpha-adrenergic receptor function.  相似文献   
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The purpose of this study was to examine speech convergence and speech evaluation in fact-finding interviews conducted in the field. Forty interviewers (ERs), undergraduates enrolled in a class on interviewing processes, conducted 20–30 minute interviews with selected interviewees (EEs), business persons and professionals in fields of interest to the ERs. Speech behaviors examined included response latency, speech rate, and turn duration; these were coded per one minute intervals of each interaction. Time series regression procedures indicated that both ERs and EEs converged speech rate and response latency toward their interlocutors' performances of these behaviors. Although turn duration convergence did not characterize the entire data set, male-male dyads did converge significantly and male (ER)-female (EE) dyads significantly diverged turn duration. Regarding speech evaluation, there was some evidence that greater response latency similarity, greater speech rate and response latency convergence, and faster ER speech and slower EE speech were positively related to the competence and social attractiveness judgments of participants. Limitations and implications are discussed.  相似文献   
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