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991.
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The aim of this study was to examine the maturation responses of young people to submaximal treadmill exercise. Body mass was controlled using both the conventional ratio standard and allometric modelling. Ninety-seven boys and 97 girls with a mean age of 12.2 years completed a discontinuous, incremental exercise test to voluntary exhaustion. We measured peak oxygen uptake (VO2peak) and VO2 when running at 8, 9 and 10 km x h(-1). Sexual maturation was assessed visually using Tanner's indices of pubic hair. Peak VO2 was significantly higher in boys (P<0.001); this was still the case when the influence of body mass was covaried out. During submaximal exercise, no significant differences in absolute VO2 were observed between the sexes (P>0.05); however, values of VO2, expressed both in ratio with body mass and adjusted for body mass using allometry, were significantly greater in boys than in girls (P<0.001). For absolute VO2, significant main effects (P<0.05) were seen for maturity at each exercise stage. With the influence of body mass controlled using either the ratio standard or allometry, no significant main effects (P>0.05) for maturity were observed. Our results indicate that boys are less economical than girls while running at 8-10 km x h(-1) and that, independently of body mass, maturation does not influence the VO2 response to submaximal exercise. 相似文献
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994.
LaBeause J Van de Water N Carey P Fielder M Sorrow B Woolbright C 《Medical reference services quarterly》1999,18(2):81-89
Health sciences librarians are being called upon to be more proactive in their institutions' continuing education efforts. In an effort to identify whether search requests indicated CE needs, a study was conducted by a group of members of GaIN (Georgia Interactive Network for Medical Information). MEDLINE requests from health care professionals for subject specific clinical topics were collected during a six-month period via a standard search request form created for the study. Copies of all completed requests were collected and broad ICD-9 codes assigned to the search topics. Institutional reports were generated for each participating library to share with hospital CE coordinators. They were also compiled for the group as a whole, and reflected the "hottest" topics requested during the study period for physicians and for non-physicians (nurses, allied health, administrators). A survey to hospital librarians and CE educators showed some value in the reports, but greater potential for further collaboration between librarians and CE coordinators. 相似文献
995.
In the summer of 2004, it was revealed that the U.S. Census Bureau had provided tabulations in 2002 and 2003 on Arab Americans to the Department of Homeland Security that included detailed information on the number of people of Arab backgrounds living in selected ZIP codes. Although not a violation of law, the Census Bureau realized that this perceived breach of confidentiality would have a negative impact on public trust, and within a few months following the news of the Arab American tabulations it announced that it would no longer assist law enforcement and intelligence agencies with tabulations on ethnic groups and other sensitive populations. In spite of this damage control, we believe that the Bureau's tabulation of Arab Americans provides momentum to a process that adversely affects data quality by increasing both non-response and the cost of obtaining survey and census data. We argue that there are no “methodological fixes” that can repair the damage, and further that public relations campaigns and internal administrative changes are not optimal solutions because of the governing structure within which the Bureau currently operates. Ultimately, the best way to limit the damage already done is to effect a political solution. Toward this end we describe short- and long-term actions. In the long run, we recommend removing the Census Bureau from the Executive branch of government and re-structuring it under a permanent and non-political oversight panel similar to either the Federal Reserve Board or the Congressional Budget Office. Such a move would make a strong statement that the Bureau is non-partisan federal statistical agency. 相似文献
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N A Badian 《Journal of learning disabilities》1986,19(5):262-269
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