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71.
This article discusses the changing relationships of authors and publishers, the current trends and challenges they face, and the direction of these relationships in the future. As the STM publishing industry finds itself in the midst of significant technological and economic changes, this article provides background to these changes and looks at the key elements, including open access business development, institutional repository trends, and emerging public financing policies in the future.  相似文献   
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ABSTRACT It is argued that sport, like science or medicine, is a valued human practice and is characterised as much by the moral manner in which its participants conduct themselves as by the pursuit of its own skills, standards and excellences. Virtues, such as justice, honesty and courage, are not only necessary to pursue its goals but to protect it from being corrupted by external interests. After explicating the practice view of sport in contrast to the sociological view, the nature of competition in sport is discussed before examining two related issues: winning at all costs and the taking of performance-enhancing drugs. The importance of practices to education and the good life is also outlined.  相似文献   
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Medicine has made increasing use of meta-analysis, largely as a quantitative procedure for combining results of clinical trials. Meta-analysis begins with a comprehensive review of the literature. The next step is a systematic analysis of the quality and content of each study. Finally, results are combined statistically and conclusions are drawn from this new overview of the data. This paper presents a brief historical perspective on the use of meta-analysis in medicine with emphasis on the medical library. The authors conclude that in the future, medical librarians will play a significant role in the application of this useful technique.  相似文献   
76.
This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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This investigation identifies demographic, media, and social correlates of verbally aggressive communication in adolescence. Mail surveys were completed and returned by 2,300 adolescents between the ages of 13 and 15. These adolescents were asked about the prevalence of verbal and physical aggression, the context in which it occurred, demographics, and the interpersonal and media influences in their lives. The results indicate that verbal aggression is widespread, that committing and experiencing verbal aggression is largely reciprocal, that there is a strong relationship between committing verbal and physical aggression, and that peer social influence and listening to violently oriented music are mildly related to verbal aggression in adolescents. These findings suggest more resources should be allocated to teaching adolescents to understand and control verbal aggression. Further, they provide important answers to many prevention and intervention programmatic questions, including context, content, and targeting concerns. Since the negative consequences of verbal aggression are severe and long lasting, decreasing this destructive communication behavior should significantly improve the lives of many adolescents. These and other practical implications are expanded upon and discussed.  相似文献   
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Ordinary markets allow parties, not the state, to value property and projects. But they do not account for subjective value in such traditional contexts as condemnation. An awareness of these nonmarket values helps overcome any categorical opposition to the use of the contingent valuation method (CVM) to value cultural and environmental resources. But accurate CVM should measure all values, positive or negative, tononowners; it should apply generally to any substitute projects; and it should seek to account for diminishing marginal value of additional resource units. CVM should be used only to aggregate nonmarket preferences, not to skew the political debate to cultural or environmental objectives.  相似文献   
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