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William F. Price 《Educational gerontology》2013,39(4):423-427
Older adults want continuing education programs that are more than just recreational activities to fill leisure time. DARE (Developing Adult Resources through Education) is an educational program for the rural aged that provides courses ranging from those of a serious, academic orientation to the hobby/recreational to the practical. A model of why adult learners engage in lifelong learning is applied to the older adult. DARE shows how college and community resources can be used for the educational advantage of the older person. 相似文献
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Professional, workplace searching is different from general searching, because it is typically limited to specific facets and targeted to a single answer. We have developed the semantic component (SC) model, which is a search feature that allows searchers to structure and specify the search to context-specific aspects of the main topic of the documents. We have tested the model in an interactive searching study with family doctors with the purpose to explore doctors’ querying behaviour, how they applied the means for specifying a search, and how these features contributed to the search outcome. In general, the doctors were capable of exploiting system features and search tactics during the searching. Most searchers produced well-structured queries that contained appropriate search facets. When searches failed it was not due to query structure or query length. Failures were mostly caused by the well-known vocabulary problem. The problem was exacerbated by using certain filters as Boolean filters. The best working queries were structured into 2–3 main facets out of 3–5 possible search facets, and expressed with terms reflecting the focal view of the search task. The findings at the same time support and extend previous results about query structure and exhaustivity showing the importance of selecting central search facets and express them from the perspective of search task. The SC model was applied in the highest performing queries except one. The findings suggest that the model might be a helpful feature to structure queries into central, appropriate facets, and in returning highly relevant documents. 相似文献
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Maternal smoking during pregnancy retards fetal growth and depresses infant birth weight. The magnitude of these effects may be moderated by fetal genotype. The current study investigated maternal smoking, fetal genotype, and fetal growth in a large population sample of dizygotic twins. Maternal smoking retarded fetal growth in a dose-dependent fashion. In a subsample of 497 twin pairs whose mothers smoked during pregnancy, a functional polymorphism in the NAD(P)H:quinone oxidoreductase gene ( NQO1 Pro187Ser; rs1800566) was significantly associated with fetal growth within families. The effect was strongest among moderate smokers. This is the first demonstration that fetal genotype for an enzyme involved in tobacco smoke metabolism influences intrauterine growth independent of maternal genotype. Future studies should conduct formal tests of Fetal Genotype × Maternal Smoking interactions. 相似文献
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The increasing number and variety of controversial scientific and technological issues with which citizens are confronted has led, in recent years, to calls for a schooling of science which prepares future citizens for participation in resolving such issues. We examined the social conscience of science teachers as it bears on the teaching of controversial issues. The study was conducted by interviewing teachers in two widely different English-speaking locations, Scotland and the United States. The research explores the perceptions of teachers with regard to the teaching of controversial issues, the problem of handling personal value positions when dealing with issues, and the tension that exists between the teaching of controversial issues and traditional value-free science curricula. © 1996 John Wiley & Sons, Inc. 相似文献