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The mass return to campus by the mature woman has become commonplace at colleges and universities across the country. According to the Bureau of the Census, almost 800,000 adults 35 years of age and over were enrolled in or attending college in October 1972 and “over half (53 percent) were women” (Young 1973, p. 39), the overwhelming majority of whom were going to college part-time. Many of these women find that their decision to return to school after an extended interruption of their formal education is both serious and significant, changing not only their own values, perceptions, and self-images but also giving rise to stress and change in their relationships with their families. The 1973 report of the National Advisory Council on Extension and Continuing Education concludes with the statement, “Perhaps most importantly, continuing education programs for women have revitalized the idea that the most important kind of learning results in changes in life styles and in self-image and often requires long and difficult struggle” (Mulligan 1973, p. 17). These changes and the consequent long and difficult struggle often prove to be disturbing, disrupting, disabling, or even disastrous.  相似文献   
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Topological relations such as inside, outside, or intersection are ubiquitous to our spatial thinking. Here, we examined how people reason deductively with topological relations between points, lines, and circles in geometric diagrams. We hypothesized in particular that a counterexample search generally underlies this type of reasoning. We first verified that educated adults without specific math training were able to produce correct diagrammatic representations contained in the premisses of an inference. Our first experiment then revealed that subjects who correctly judged an inference as invalid almost always produced a counterexample to support their answer. Noticeably, even if the counterexample always bore a certain level of similarity to the initial diagram, we observed that an object was more likely to be varied between the two drawings if it was present in the conclusion of the inference. Experiments 2 and 3 then directly probed counterexample search. While participants were asked to evaluate a conclusion on the basis of a given diagram and some premisses, we modulated the difficulty of reaching a counterexample from the diagram. Our results indicate that both decreasing the counterexample density and increasing the counterexample distance impaired reasoning performance. Taken together, our results suggest that a search procedure for counterexamples, which proceeds object-wise, could underlie diagram-based geometric reasoning. Transposing points, lines, and circles to our spatial environment, the present study may ultimately provide insights on how humans reason about topological relations between positions, paths, and regions.  相似文献   
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Background/Objective: This study explored the association between active school travel (AST) and suicide attempts among adolescents in low- and middle-income countries (LMICs). Method: We used the data from the Global School-based Health Survey, including 127,097 adolescents aged 13-17 years from 34 LMICs. A self-reported survey was used to collect data on AST and suicide attempts as well as some variables. Multivariable logistic regression was performed to assess the association between AST and suicide attempts. A meta-analysis with random effects was undertaken to identify the difference in the association between AST and suicide attempts. Results: Across all the adolescents, the prevalence of AST was 37% and the prevalence of suicide attempts was 11.60%. Adolescents who engaged in AST were less likely to have suicide attempts irrespective of gender. The country-wise analysis indicated a large inconsistency in the association between AST and suicide attempt across the countries. Conclusions: AST would appear to be a protective factor for reducing suicide attempts among adolescents. However, the association between AST and suicide attempts varied greatly across the countries. Future studies should confirm the association between AST and suicide attempts.  相似文献   
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