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991.
通过2005-20084年奥运周期内国际重大女排比赛相关数据整理,对世界7大强队在比赛成绩、身体条件、年龄、技战术、球队把握比赛能力以及球队人员更新率等竞技特征进行比较,同时做出这些数据与北京奥运会女排比赛成绩的相关性分析。从中更好的把握高水平女子排球运动的发展动向,全面对比世界各强队的竞技特征。为研究下一届奥运周期女排相关竞技特征提供参考依据。 相似文献
992.
Barr-Anderson DJ Neumark-Sztainer D Schmitz KH Ward DS Conway TL Pratt C Baggett CD Lytle L Pate RR 《Research quarterly for exercise and sport》2008,79(1):18-27
The current study examined associations between physical education (PE) class enjoyment and sociodemographic, personal, and perceived school environment factors among early adolescent girls. Participants included 1,511 sixth-grade girls who completed baseline assessments for the Trial of Activity in Adolescent Girls, with 50% indicating they enjoyed PE class a lot. Variables positively associated with PE class enjoyment included physical activity level, perceived benefits of physical activity, self-efficacy for leisure time physical activity, and perceived school climate for girls' physical activity as influenced by teachers, while body mass index was inversely associated with PE class enjoyment. After adjusting for all variables in the model, PE class enjoyment was significantly greater in Blacks than in Whites. In model testing, with mutual adjustment for all variables, self-efficacy was the strongest correlate of PE class enjoyment, followed by perceived benefits, race/ethnicity, and teachers' support for girls' physical activity, as compared to boys, at school. The overall model explained 11% of the variance in PE class enjoyment. Findings suggest that efforts to enhance girls' self-efficacy and perceived benefits and to provide a supportive PE class environment that promotes gender equality can potentially increase PE class enjoyment among young girls. 相似文献
993.
Meghan L. Critchley Daniel J. Davis Michaela M. Keener Jacob S. Layer Margaret A. Wilson Qin Zhu 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(4):421-437
ABSTRACT The purpose was to quantify the effects of mid-flight whole-body and trunk rotation on knee mechanics in a double-leg landing. Eighteen male and 20 female participants completed a jump-landing-jump task in five conditions: no rotation, testing leg ipsilateral or contralateral (WBRC) to the whole-body rotation direction, and testing leg ipsilateral (TRI) or contralateral to the trunk rotation direction. The WBRC and TRI conditions demonstrated decreased knee flexion and increased knee abduction angles at initial contact (2.6 > Cohen’s dz > 0.3) and increased peak vertical ground reaction forces and knee adduction moments during the 100 ms after landing (1.7 > Cohen’s dz > 0.3). The TRI condition also showed the greatest knee internal rotation angles at initial contact and peak knee abduction and internal rotation angles and peak knee extension moments during the 100 ms after landing (2.0 > Cohen’s dz > 0.5). Whole-body rotation increased contralateral knee loading because of its primary role in decelerating medial-lateral velocities. Trunk rotation resulted in the greatest knee loading for the ipsilateral knee due to weight shifting and mechanical coupling between the trunk and lower extremities. These findings may help understand altered trunk motion in anterior cruciate ligament injuries. 相似文献
994.
Schools are increasingly exploring the implementation of multitiered systems of support. This article reviews the literature pertaining to efforts to promote self-determination to provide initial direction as to how interventions and supports to promote self-determination could be implemented within a tiered framework. The intent is to provide direction to the field on how such an approach can engage all students—including students with and without disabilities—in their learning across the lifespan to promote positive school and postschool outcomes. Specifically, we review interventions and supports that have been described in the literature pertaining to self-determination, organizing our review and analysis around the traditional three-tier approach. Implications for future research and development to promote the universal applicability of self-determination are discussed. 相似文献
995.
L. DiAnne Borders Laura M. Gonzalez Lindsey K. Umstead Kelly L. Wester 《Counselor Education & Supervision》2019,58(4):293-308
Eighteen new counselor educators shared in‐depth reports of their efforts to establish an early record of scholarly productivity, critical to their success in academe. Analyses of their experiences using consensual qualitative research methods revealed components of both highly positive and highly discouraging program environments and their impact on participants’ research goals. 相似文献
996.
Ruth Jeanes Ramón Spaaij Jonathan Magee Karen Farquharson Sean Gorman Dean Lusher 《Sport in Society》2019,22(6):986-1004
AbstractInterventions aimed at increasing the participation of young people with disabilities in recreational sport have had mixed success. The authors draw on in-depth interviews with representatives from State Sporting Associations, local government officers and volunteers within community sports clubs in Victoria, Australia, to examine why some sports clubs are unable or unwilling to translate policy ambitions into practice. The findings indicate how by framing disability provision as ‘too difficult’, ‘not core business’ and antithetical to competitive success, community sports clubs are able to resist policy ambitions to modify existing structures and develop more inclusive practice. Greater priority needs to be given to transformational inclusion objectives and challenging ableism if clubs are to structurally progress the development of participation opportunities for young people with disabilities. 相似文献
997.
目的:通过分析第二届青运会排球专项身体素质成绩、项目设置及与比赛名次的关系,为青年排球专项身体素质测试及训练提供有借鉴意义的参考。方法:收集第二届青年运动会男排U18组和女排U17组24支球队的专项身体素质成绩和比赛名次进行统计并分析二者相关性。结果:男排U18组和女排U17组助跑摸高的成绩分别为(3.24±0.11) m、(2.91±0.11) m,占总分比为20.1%、21.9%;半“米”字移动成绩分别为(15.66±0.74) s、(16.95±0.84) s,占总分比为20.8%、18.1%;30 m跑成绩分别为(4.35±0.18) s、(4.98±0.23) s,占总分比为23.2%、18.2%;抛掷实心球成绩分别为(12.32±1.82) m、(9.22±1.45) m,占总分比为23.0%、22.1%;男子1 500 m项目平均成绩为(337.14±28.79) s,占总分比为12.8%,女子800 m成绩为(183.10±22.28) s,占总分比为19.6%。男排U18组和女排U17组身体素质总分与比赛名次呈负相关,差异有统计学意义(P<0.01),即身体素质总分越高,比赛名次越靠前。结论与建议:男排U18组和女排U17组各队助跑摸高成绩差距最小,半“米”字移动、抛掷实心球和1 500 m(800 m)跑成绩差距较大;女排U17组身体素质项目各项得分较为均衡,成绩设置合理,男排U18组1 500 m项目设置的必要性及得分设定需进一步分析研讨;青年排球专项身体素质成绩越高,比赛名次越好,目前采用的专项身体素质测试方法较为合理,对竞赛成绩有较好预测性。 相似文献
998.
中国科技期刊开放存取出版现状 总被引:33,自引:1,他引:33
基于《2005年版中国科技期刊引证报告》所收录的1608种我国科技期刊,搜索并统计分析了我国科技期刊的开放存取出版(open access publishing,OAP)现状.结果表明:我国OA期刊已具有一定的数量规模(143种),但部分期刊OA出版的持续性较差,且大都为单刊OA,难以形成信息集成的优势;医学、生物学、农业科学和化学领域中OA期刊的数量相对较多,并且,在同领域中OA期刊的引证影响明显高于非OA期刊.认为我国的相关部门不仅要致力于组建稳定可靠的、有较大信息量的OA期刊网站,而且要关注学术论文的开放存档(open archive). 相似文献
999.
Larry L. Howard 《Economics of Education Review》2011,30(1):157-176
This paper estimates models of the transitional effects of food insecurity experiences on children's non-cognitive performance in school classrooms using a panel of 4710 elementary students enrolled in 1st, 3rd, and 5th grade (1999-2003). In addition to an extensive set of child and household-level characteristics, we use information on U.S. counties to control for potential confounding effects of the local economic and noneconomic environment on children's household transitions between states of food insecurity and food security. The time horizon of our analysis affords insight into factors underlying children's formation of non-cognitive skills and the efficiency of classroom-based educational production in elementary school. Overall, we find significant negative developmental effects for children with food insecurity at home; and that children experiencing an early transition from food insecurity in 1st grade to food security in 3rd grade have even larger impairments that persist through 5th grade. 相似文献
1000.
Academic Functioning and Peer Influences: A Short‐Term Longitudinal Study of Network–Behavior Dynamics in Middle Adolescence 下载免费PDF全文
J. Ashwin Rambaran Andrea Hopmeyer David Schwartz Christian Steglich Daryaneh Badaly René Veenstra 《Child development》2017,88(2):523-543
In this study, the associations between peer effects and academic functioning in middle adolescence (N = 342; 14–15 years old; 48% male) were investigated longitudinally. Similarity in achievement (grade point averages) and unexplained absences (truancy) was explained by both peer selection and peer influence, net of acceptance, and connectedness. Friendships were formed and maintained when adolescents had low levels of achievement or high levels of truancy. Friends influenced one another to increase rather than decrease in achievement and truancy. Moreover, friends’ popularity moderated peer influences in truancy in reciprocal friendships but not in unilateral friendships, whereas friends’ acceptance moderated peer influences in achievement in both unilateral and reciprocal friendships. The findings illustrate the dynamic interplay between peer effects and academic functioning. 相似文献