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The purpose of this investigation was to describe the morphological parameters that characterize elite age group divers. Comparisons are made to normative age group data from the Coquitlam Growth Study and the constancy of important characteristics from age group to age group is examined. Data were collected on 27 male and 28 female elite divers who participated in the 1990 North American Age Group Diving Championships. Body build, body composition and skinfold corrected diameters were determined from 36 anthropometric parameters and analysed by ANOVA, t-test and Phantom z-scores procedures. All age groups except the 14- to 15-year-old males were significantly (P < or = 0.05) shorter than their norms but recorded higher androgyny index values. The estimated relative muscle mass increased significantly (P < or = 0.05) with age for males at all ages (40.8-46.3%). The 16- to 18-year-old females had a significantly (P < or = 0.05) larger relative muscle component compared to the younger age groups (40.1-38.4%). When normalized for height, active tissue development of the extremities was comparable between the sexes except in the forearm. The results indicate that at all age levels short stature is an important characteristic for divers. Analysis of regional active tissue development provides further insight into sport-specific prerequisites for success at elite levels. 相似文献
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John Ashworth 《Higher Education Quarterly》1997,51(2):164-188
Since 1990, there has been considerable debate concerning the benefits of the expansion of higher education and the appropriate way to fund such an expansion. This paper demonstrates that three factors are decisive to the individual contemplating higher education: national economic growth; the relative earnings of graduates and non-graduates; the difference between the average and the marginal student. The results, of analysis based on rates of return, reaffirm the view that a proportion of the costs involved in higher education can be transferred to the graduates themselves in the form of loans. However, there appear to be limits to the costs that can be transferred if all students are to judge that undergraduate study is a worthwhile proposition. Notwithstanding this, most students could be lent more income to study than is now the case and indeed an average student would be advised to take any loans despite the greater debt. Marginal students, however, are making a risky private investment and, therefore, any decisions to further expand may result in students not taking up the places. 相似文献
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John Wilkin 《中国图书馆学报》2008,34(4)
我们长期将数字图书馆作为一个独立的世界来构建,这个独立的世界中包括数字对象的创建、管理、发现、传递以及利用等。这种相对封闭的模式与高度发达的开放网络世界背道而驰。在网络世界中,用户可以通过大型的检索系统,如Google和Amazon来发现信息,还可以在管理这些信息资源的系统之外对其进行利用。当用户都涌向网络世界时,数字图书馆就面临着打破其固有封闭状态的挑战,以便适应开放的网络世界,否则将失去其实用性。当前,许多条件都给数字图书馆提供了改变现状、提高实用性的机遇。本文将讨论数字图书馆现存的典型模式以及该模式带来的后果,讨论数字图书馆工作改革的方式,并简要探讨数字图书馆建设中的成功技术实例。 相似文献
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