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31.
Steve Graham Evan J. Fishman Robert Reid Michael Hebert 《Learning disabilities research & practice》2016,31(2):75-89
Students with Attention Deficit Hyperactivity Disorders (ADHD) frequently experience significant difficulty mastering basic academic skills. This meta‐analysis focuses on one specific potential area of learning difficulties for these students: namely, writing. To identify the extent and depth of the potential writing challenges faced by students with ADHD, we conducted a meta‐analysis comparing the writing performance of grade 1 to 12 students with ADHD to their normally achieving peers. We located 44 papers, yielding 45 studies with 87 effect sizes. The average weighted effect sizes showed that students with ADHD obtained lower scores than their normally achieving peers for writing quality (–0.78), output (–0.64), number of genre elements (–0.69), vocabulary (–0.76), spelling (–0.80), and handwriting (–0.62). Contrary to expectations, moderator analyses found that neither study quality nor the source from which ADHD students were drawn (i.e., school/community vs. clinic/hospital) accounted for variability above sampling error alone. 相似文献
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Samuel W. Oxford Rob S. James Michael J. Price Carl J. Payton Michael J. Duncan 《Journal of sports sciences》2017,35(16):1658-1665
The purpose of this study was to compare arm–leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm–leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency. 相似文献
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Carl T. Woods James P. Veale Neil Collier Sam Robertson 《Journal of sports sciences》2017,35(4):325-330
This study investigated the extent to which position in the Australian Football League (AFL) national draft is associated with individual game performance metrics. Physical/technical skill performance metrics were collated from all participants in the 2014 national under 18 (U18) championships (18 games) drafted into the AFL (n = 65; 17.8 ± 0.5 y); 232 observations. Players were subdivided into draft position (ranked 1–65) and then draft round (1–4). Here, earlier draft selection (i.e., closer to 1) reflects a more desirable player. Microtechnology and a commercial provider facilitated the quantification of individual game performance metrics (n = 16). Linear mixed models were fitted to data, modelling the extent to which draft position was associated with these metrics. Draft position in the first/second round was negatively associated with “contested possessions” and “contested marks”, respectively. Physical performance metrics were positively associated with draft position in these rounds. Correlations weakened for the third/fourth rounds. Contested possessions/marks were associated with an earlier draft selection. Physical performance metrics were associated with a later draft selection. Recruiters change the type of U18 player they draft as the selection pool reduces. juniors with contested skill appear prioritised. 相似文献
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Paul W. Grimes Joyce E. Nielsen James F. Niss 《The American journal of distance education》2013,27(2):36-43
Abstract Correspondence study represents the first and most persistent distance education format in American universities. Later called independent study, it enabled universities to disseminate instruction far beyond their campuses. Yet, national‐level leadership provided by the National University Continuing Education Association (NUEA) and its divisions has been relatively restrained. In contrast, leadership in the private correspondence school sector has been assertive, and sometimes even aggressive. The NUEA and its members shunned this approach, choosing instead to lead by persuasion and example. The NUEA developed standards of practice concerned primarily with replicating on‐campus teaching styles and values, rather than the promotion of distance education. With the abolition of its division structure, the NUEA's successor, the University Continuing Education Association (UCEA), has opted out of a leadership role in independent study. This paper concludes that the NUEA's initial attempt at leadership in distance education— while reasoned and principled—contained flaws that made failure inevitable. 相似文献
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