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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
4.
Development of maximal oxygen uptake in young elite male cross-country skiers: a longitudinal study.
F Ingjer 《Journal of sports sciences》1992,10(1):49-63
The aim of this study was to investigate the effects of extensive endurance training (15-25 h per week) on the development of maximal oxygen uptake (VO2 max) in boys from puberty. Maximal oxygen uptake was measured a number of times each year from the age of puberty and for the next 6-9 years in seven young male elite cross-country skiers. Mean VO2 max was measured as 76.3 and 80.1 ml kg-1 min-1 at the ages of 14 and 15 years respectively. Despite the fast rate of growth during puberty, maximal aerobic power showed seasonal variations from the age of 14, reaching a plateau at the age of 15, whereas VO2 max (ml kg-2/3 min-1) increased continuously. It is concluded that, during puberty, boys probably attain significant increases in VO2 max when appropriate amounts of endurance training are undertaken. 相似文献
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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
8.
John M. Budd 《Publishing Research Quarterly》1991,7(2):27-37
In recent years university presses have undergone some significant changes, such as expansion of their scope to include materials
that may have appeal beyond the scholarly market. This article investigates, through the use of a survey of university libraries,
the acquisition of university press products by libraries. In general, recent years have been changes in the relationship
between university presses and libraries that have resulted in fewer items being purchased by the libraries. 相似文献
9.
Donald D. Deshler Jean B. Schumaker B. Keith Lenz Janis A. Bulgren Michael F. Hock Jim Knight Barbara J. Ehren 《Learning disabilities research & practice》2001,16(2):96-108
Three factors tied with secondary student success in content‐area reading are demonstrated: (a) validated teacher‐focused and student‐focused interventions, (b) integrated and comprehensive service delivery systems, and (c) well‐designed, data‐based professional developmental programs. Difficult challenges face secondary students with LD and their teachers with regard to these students’ participation and success in required general education classes. Recently, instructional methods and materials have been developed and validated for promoting these students’ success. Some of them focus on how general education teachers plan and teach their content‐area courses; others focus on giving students the strategies they need to respond independently to the demands of their courses. This article describes these instructional methods, a service‐delivery model for implementing these interventions in secondary schools, and professional‐development mechanisms and administrative support that must be in place for the model to be maintained effectively. 相似文献
10.
Peter Davison 《Learned Publishing》2003,16(4):243-247
The Copyright Licensing and Administration Society of Singapore was established in 1999. It is now profitable and commercially significant, perhaps uniquely so in Asia. Critical factors in its growth have included a statutory (non‐voluntary) photocopying licence provision for educational institutions in the Copyright Act; and widespread support from the local and international communities of rightsholders. Tentative consensus has been established with educators over a fair level of remuneration for copying. Further work needs to be done to extend or amend the current model for electronic copying, for the private sector and for other countries in the region. 相似文献