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1.
Continuous observation of the physical activity of 56 preadolescent children was conducted in four regions of England from October 1988 to July 1989. Observations were undertaken during school break times, lunch times, and physical education lessons, as well as during the children's free time. Of total time observed, the children spent 32.4% of it engaged in moderate to vigorous physical activity (MVPA). Children were shown to be most active during school breaks and least active during free time at home. However, it is thought that cardiorespiratory benefits are best achieved by participation in sustained periods of MVPA. Only 8 (14%) of the 56 children were observed to participate in MVPA for sustained periods of 20 min or longer. A random sample of 55 physical education lessons was observed. Only 6 children engaged in MVPA for sustained periods of 5 min or more, and no children participated in MVPA for 10 min or longer. The implications of these results are that, although the children engaged in a reasonable amount of MVPA, it may not have been sustained for periods of sufficient length to produce a cardiovascular training response. Consideration is given to ways of promoting lifelong involvement in physical activity. 相似文献
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Lisa M. W. DaDeppo 《Learning disabilities research & practice》2009,24(3):122-131
Despite increased enrollment, outcomes such as grade point average (GPA), persistence, and graduation rates for college students with learning disabilities (LD) continue to lag behind those of their nondisabled peers. Reasons for the differences vary but may include academic and social integration, factors identified as important to the success of college students in general. This research investigated the relative influence of background characteristics, precollege achievement, and college integration variables on the academic success and intent to persist of college freshmen and sophomores with LD. While academic and social integration were not unique predictors of college GPA, both integration variables were unique predictors of intent to persist. The findings suggest that beyond high school achievement and background characteristics, college experiences as captured by academic and social integration are promising constructs to help explain the persistence of college students with LD. Implications for future research and practices for high school and college personnel are discussed. 相似文献
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Sports Engineering - A Monark cycle ergometer is a device globally used in physiological studies to measure the work and energy levels of exercising humans. In this paper a rope-braked cycle... 相似文献
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G L Zellman 《Child abuse & neglect》1992,16(1):57-74
Drawing distinctions on the basis of at least some case characteristics in making reporting decisions makes considerable sense. Using data from a national survey of mandated reporters that included vignettes in which case and personal characteristics were systematically varied, this paper examines the impact of selected characteristics while controlling for others. The data reveal that respondents noticed and responded to case characteristics. Abuse-relevant judgments and reporting intentions varied, often substantially, as a function of case characteristics. Three case characteristics--previous abuse, severity of abuse, and recantation--were powerful predictors of vignette outcomes. A history of previous abuse led to judgments of greater seriousness, a more salutary impact of a report, and greater likelihood of reporting. More severe abuse was more likely to be labelled as abuse, and was more likely to be reported. When the alleged victim retracted her accusation upon questioning by an authority figure, respondents were significantly less likely to intend a report. Child age, perpetrator intent and family socioeconomic status also influenced abuse-relevant judgments and reporting intentions. Respondents were more likely to intend a report when younger children, lazy or angry perpetrators and children from poorer families were portrayed. 相似文献
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How has Item Response Theory helped solve problems in the development and use of computer-adaptive tests? Do we need to balance item content with computer-adaptive tests? Could we use IRT to evaluate unusual responses to computer-delivered tests? 相似文献
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L A Colaianni 《Bulletin of the Medical Library Association》1992,80(1):1-8
The 1991 Janet Doe lecturer describes the vision held by the founders of the Medical Library Association of medical information being readily accessible to health professionals no matter how far they were located from major medical centers, and traces the pursuit of this vision to current outreach activities. 相似文献
9.
Wendy M. Yen 《Educational Measurement》1997,16(3):5-15
How accurate is the reported percent of students’reaching standards at the school level? How are standard errors for these statistics computed? How do estimates vary with choice of generalizability model? 相似文献
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