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911.
A study was devised to investigate the role of physical fitness in moderating both cognitive work capacity and fatigue onset under sustained combat operations. Sixteen male ROTC cadets were followed through a 2.5-day, Pre Ranger Evaluation exercise. Prior to the start of the exercise, the cadets’ overall level of physical fitness was assessed by using five fitness indices (Harvard Step Test, chin-ups, push-ups, sit-ups, and two-mile run). Cognitive performance and subjective measures of fatigue state were assessed at regular intervals before, during, and 1 day after the exercise. The results suggest that fitness may attenuate decrements in cognitive work capacity for certain tasks requiring prolonged mental effort, particularly as the cumulative effects of sleep loss and other stressors begin to mount. Similarly, the results suggest that as overall stress levels increase, fitness may have a beneficial effect in moderating fatigue rate. Fitness did not significantly enhance the recovery process with respect to cognitive work capacity, and actually appeared to hinder recovery from fatigue.  相似文献   
912.
This study examines data from questionnaires to establish the prevalence and correlates of women's binge drinking, defined as four or more drinks per episode, at women's colleges ( n = 508) and at coeducational colleges ( n = 9,624). Results showed that women at women's colleges binged less frequently, had fewer alcohol-related problems, experienced fewer negative effects of others' drinking, and were less likely to drink and drive. The correlates of binge drinking were similar for the two groups of women. The differences appear to be related not to the quantity or amount of socializing but to its quality. The absence of fraternities and coeducational dormitories, the reduced likelihood of a party-centered lifestyle, and self-selection factors at women's colleges all may contribute to a healthier environment for women. Interventions designed to lower the risk of college binge drinking should further explore the peer-group contexts in which problem drinking is reduced.  相似文献   
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Recent studies have made great strides looking at the implications that the human need for ontological security has for politics and International Relations. However, less attention has been paid to how actors might target this need. While Steele and Mattern both examine the possible manipulation of subjectivity, this article turns to the concept of information warfare (IW) to broaden the view of how, and to what end, this is pursued. Congruently, by elaborating upon how the digitalization of society has increased the potential to influence and manipulate cognition and emotion, OS strengthens current literature on IW. It argues that by covertly perverting the information landscape, IW can alter how events are connected to national narratives, influencing policy by making certain options appear more/less shameful, or it can unravel the bonds of society by polarizing domestic narrative debates, purposely sowing ontological insecurity. This provides a firmer understanding of the strategic implications interference can have generally and of Russia's interference into the 2016 U.S. election specifically. Therefore, by viewing facets of IW as part of a range of tactics employed to manipulate/undermine subjectivity, a more nuanced understanding of interstate relations subsequently emerges.  相似文献   
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The reinforcer pathologies model of addiction posits that two characteristic patterns of operant behavior characterize addiction. Specifically, individuals suffering from addiction have elevated levels of behavioral economic demand for their substances of abuse and have an elevated tendency to devalue delayed rewards (reflected in high delay discounting rates). Prior research has demonstrated that these behavioral economic markers are significant predictors of many of college students' alcohol-related problems. Delay discounting, however, is a complex behavioral performance likely undergirded by multiple behavioral processes. Emerging analytical approaches have isolated the role of participants' sensitivity to changes in reinforcer magnitude and changes in reinforcer delay. The current study uses these analytic approaches to compare participants' discounting of money versus alcohol, and to build regression models that leverage these new insights to predict a wider range of college students' alcohol related problems. Using these techniques, we were able to 1) demonstrate that individuals differed in their sensitivity to magnitudes of alcohol versus money, but not sensitivity to delays to those commodities and 2) that we could use our behavioral economic measures to predict a range of students' alcohol related problems.  相似文献   
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Food pellets were programmed to be delivered to rats every 60 sec (Fixed Time 60-sec schedule), and the development of schedule-induced drinking was measured in terms of the amount of water consumed and the number of licks per inter-pellet interval. For some rats (masters) 10-sec delays in food delivery were dependent on licks. Yoked-control rats received food at the same time as their masters and independently of their own behaviour. In Experiment 1, in which the delays were signalled by a blackout, the master rats began to drink, but this schedule-induced behaviour then decreased to levels lower than those shown by the yoked controls. When the signalled delays were discontinued, the drinking of the master rats recovered. In Experiment 2, in which the delays were not signalled, the master rats did not develop as much schedule-induced drinking as the yoked controls, and discontinuing the delays led to only small increases in drinking. These results support the view that schedule-induced drinking is subject to control by its consequences.  相似文献   
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