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61.
A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity.  相似文献   
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How do speakers design what they say in order to communicate effectively with groups of addressees who vary in their background knowledge of the topic at hand? Prior findings indicate that when a speaker addresses a pair of listeners with discrepant knowledge, that speakers Aim Low, designing their utterances for the least knowledgeable of the two addressees. Here, we test the hypothesis that speakers will depart from an Aim Low approach in order to efficiently communicate with larger groups of interacting partners. Further, we ask whether the cognitive demands of tracking multiple conversational partners' perspectives places limitations on successful audience design. We find that speakers can successfully track information about what up to four of their partners do and do not know in conversation. When addressing groups of 3–4 addressees at once, speakers design language based on the combined knowledge of the group. These findings point to an audience design process that simultaneously represents the perspectives of multiple other individuals and combines these representations in order to design utterances that strike a balance between the different needs of the individuals within the group.  相似文献   
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Indiana statute allows police to seize firearms without a warrant if the officer believes a person meets the law's definition of “dangerous.” Review of the use of this law in Marion County (Indianapolis), Indiana, showed that prosecutors filed petitions in court to retain weapons seized by police under this law 404 times between 2006 and 2013. Police removed weapons from people due to identification of a risk of suicide (68%) or violence (21%), or the presence of psychosis (16%). The firearm seizures occurred in the context of domestic disputes in 28% of cases and intoxication was noted in 26% of cases. There were significant demographic differences in the circumstances of firearm seizures and the firearms seized. The seized firearms were retained by the court at the initial hearing in 63% of cases; this retention was closely linked to the defendant's failure to appear at the hearing. The court dismissed 29% of cases at the initial hearing, closely linked to the defendant's presence at the hearing. In subsequent hearings of cases not dismissed, the court ordered the destruction of the firearms in 72% of cases, all when the individual did not appear in court, and dismissed 24% of the cases, all when the individual was present at the hearing. Overall, the Indiana law removed weapons from a small number of people, most of whom did not seek return of their weapons. The firearm seizure law thus functioned as a months-long cooling-off period for those who did seek the return of their guns. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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