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The questionnaire survey reported in this paper is part of an ongoing evaluation of the effect of a bursary scheme on recruitment to Cambridge University. It sought to identify factors that encouraged or discouraged highly successful A Level students from applying to Cambridge. Findings reveal three main dimensions associated with the decision to apply to Cambridge, the nature of the courses, the prestige of the university and anxiety about the application process combined with fear of failure. Further analyses showed that there were complex interactions between these three dimensions which governed the decision to apply to Cambridge. These findings are relevant to other prestigious universities. The availability of a bursary did appear to influence the decisions of those who were eligible, but its influence was not as great as some of the other factors.  相似文献   
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PURPOSE: Chest radiographs (CXR) are the standard method for evaluating rib fractures in abused infants. Computed tomography (CT) is a sensitive method to detect rib fractures. The purpose of this study was to compare CT and CXR in the evaluation of rib fractures in abused infants. METHODS: This retrospective study included all 12 abused infants identified from 1999 to 2004 who had rib fractures and both CXR and CT (8 abdomen CTs, 4 chest CTs). CT exams had been performed for clinical indications, and were obtained within one day of the CXR. Studies were reviewed by two pediatric radiologists to determine the number, locations, and approximate ages of the rib fractures. A total of 225 ribs were completely (192) or partially (33) seen by CT, and the matched ribs on CXR were used for the analysis. RESULTS: The mean patient age was 2.5 months (1.2-5.6), with seven females and five males. While 131 fractures were visualized by CT, only 79 were seen by CXR (p<.001). One patient had fractures only seen by CT. There were significantly (p<.05) more early subacute (24 vs. 4), subacute (47 vs. 26), and old fractures (4 vs. 0) seen by CT than by CXR. Anterior (42 vs. 11), anterolateral (21 vs. 12), posterolateral (9 vs. 3) and posterior (39 vs. 24) fractures were better seen by CT than by CXR (p<.01). Bilateral fractures were detected more often by CT (11) than by CXR (6). CONCLUSIONS: While this study group is small, these findings suggest that CT is better than CXR in visualizing rib fractures in abused infants.  相似文献   
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Four pigeons were exposed to several nonindependent concurrent variable-interval schedules of reinforcement. One schedule component required a keypecking response; the other component required a treadlepressing response. The birds matched the ratio of their behavior (as measured by responses and time) between the two topographically different responses to the ratio of reinforcement in those two components. When additional foods not contingent on a keypeck or treadle-press were then added, the birds matched time spent in the components to total rates of food delivered in those components; response matching was somewhat disrupted. The matching law, developed under concurrent variable-interval schedules requiring similar responses, can thus account for choice behavior involving topographically different responses.  相似文献   
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