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991.
Reading readiness varies as a function of family and environmental variables. This study of 11-year-old children (N = 39) was designed to determine if there was an additional or interactive contribution of brain structure. Evidence is presented that both environmental and biological variables predict phonological development. Temporal lobe (planar) asymmetry, hand preference, family history of reading disability, and SES explained over half of the variance in phonological and verbal performance. The results demonstrate a linear association between cerebral organization and phonological skill within socioeconomic groups. These data provide concrete evidence to support the commonly held assumption that both environmental and biological factors are independent determinants of a child's ability to process linguistic information. 相似文献
992.
993.
Messerle J 《Bulletin of the Medical Library Association》2001,89(1):1-7
The annual Janet Doe Lecture was established in 1966 to honor Janet Doe, emerita librarian of the New York Academy of Medicine. The lecture focuses on either the history or philosophy of health sciences librarianship. This lecture addresses three fundamental values of the field, highlighting basic beliefs of the profession that are at risk: privacy, intellectual property rights, and access to quality information. It calls upon readers to make the everyday choices required to keep the value system of health sciences librarianship in place. Robert Frost's poignant poem "The Road Not Taken" provides the metaphor for examining choices in an information economy. 相似文献
994.
We examined the supposition that swimmers may exhibit an imbalance in bilateral arm power output during simulated swimming exercise. Ten competitive front crawl swimmers (5 males, 5 females; age 20.5+/-2.3 years; height 1.74+/-0.09 m; body mass 72.0+/-16.7 kg; 400 m freestyle swim time 278+/-20.5 s; mean +/- s) performed four incremental (10 W x min(-1)) swim ramp tests on a computer-interfaced biokinetic swim bench ergometer. External power output from each arm was measured continuously to exhaustion. The results showed that, throughout the course of the simulated swim, external power output clearly favoured the left arm (F1,9 = 12.5, P= 0.006). This was especially evident in the final 30 s to exhaustion, when 54.0+/-3.87% of external power output was derived from the left arm versus 46.0+/-3.87% from the right arm. The disparity in external power output was further highlighted when the participants were grouped into unilateral and bilateral breathers. Unilateral breathers (n = 5) produced 57.1+/-2.62% of external power output from the left armversus 42.9+/-2.62% from the right arm (P= 0.001). Bilateral breathers (n = 5) exhibited a more balanced external power output of 51.0+/-1.82% from the left arm and 49.0+/-1.82% from the right arm (P = 0.177). Evidence of power imbalance in the simulated swimming stroke may have important implications for optimizing swim performance. The observed power imbalance may be reduced when a bilateral breathing technique is adopted. 相似文献
995.
Halverson, Roberton, and Langendorfer (1982) reported the development of children ages 6-13 years filmed longitudinally performing the forceful overarm throw. These authors described the children's progress through developmental sequences for trunk, humerus, and forearm actions; however, they did not study developmental relationships ("profiles") across these components. This paper reports how the profiles changed in the same children across trials within filming sessions and over time. The data revealed both common and individual developmental pathways. The frequencies of some pathways were not chance occurrences (p < or = .01), suggesting that within-person constraints eliminated certain movement relationships while encouraging others. The authors hypothesize that the kinematics of trunk rotation may serve as a control parameter for pattern change. 相似文献
996.
Visual search and biological motion perception in tennis 总被引:1,自引:0,他引:1
997.
Gaining Independence: A Manual for Planning the Launch of a Nonprofit Electronic Publishing Venture, version 1.0 by Howard Goldstein Published by SPARC, available online: http://www.arl.org/sparc/GI Indexers and Indexing in Fact and Fiction edited by Hazel K. Bell The British Library, London, 2001. Pp. 160. Paper, £16. ISBN 0-7123-4729-1 Preservation Management of Digital Materials: A Handbook by Maggie Jones and Neil Beagrie The British Library, Nov. 2001. Pp. 145. Spiral bound, £15.00. ISBN 0 7123 0886 5. Copies can be ordered from Turpin Distribution Services Ltd. Publishing Law, 2nd edn by Hugh Jones and Christopher Benson Routledge, 2002. Cased, £65.00, ISBN 0-415-26153-8; paper, £24.99, ISBN 0-415-26154-6 How to Survive Peer Review by Elizabeth Wager, Fiona Godlee and Tom Jefferson London: BMJ Books, 2002. Pp. v + 62. £12.95. ISBN 0-7279-1686-6 相似文献
998.
999.
Grant SJ Oommen G McColl G Taylor J Watkins L Friel N Watt I McLean D 《Journal of sports sciences》2003,21(12):1009-1015
Different methods of ball carrying can be used when a player runs with the ball in rugby union. We examined how three methods of ball carrying influenced sprinting speed: using both hands, under the left arm and under the right arm. These methods were compared with running without the ball. Our aim was to determine which method of ball carrying optimizes sprinting speed. Altogether, 48 rugby union players (age 21 +/- 2 years, height 1.83 +/- 0.1 m, body mass 85.3 +/- 12 kg, body fat 14 +/- 5%; mean +/- s) were recruited. The players performed twelve 30-m sprints in total (each player performed three trials under each of three methods of carrying the ball and sprinting without the ball). The design of the study was a form of Latin rectangle, balanced across the trial order for each of the methods and for pairwise combinations of the methods in blocks of four per trial. Each sprint consisted of a 10-m rolling start, followed by a 20-m timed section using electronic timing gates. Compared with sprinting 20 m without the ball (2.58 +/- 0.16 s), using both hands (2.62 +/- 0.16 s) led to a significantly slower time (P < 0.05). Sprinting 20 m with the ball under the left arm (2.61 +/- 0.15 s) or under the right arm (2.60 +/- 0.17 s) was significantly quicker than when using 'both hands' (P < 0.05), and both these methods were significantly slower than when running without the ball (P < 0.05). Accordingly, running with the ball in both hands led to the greatest decrement in sprinting performance, although carrying the ball under one arm also reduced the players' sprinting ability. Our results indicate that to gain a speed advantage players should carry the ball under one arm. 相似文献
1000.
Three studies are reported of children and youth aged 11-19 years (n = 3478) examining the nature of beliefs about athletic ability. Drawing on related research in academic, moral and stereotyping domains, development of a psychometric instrument assessing athletic ability beliefs is detailed. Support was found for a multidimensional hierarchical structure that is invariant across age and gender. Confirmatory factor analysis revealed a structure comprising two higher-order factors of entity and incremental beliefs underpinned by beliefs that athletic ability is stable and a gift (entity), and is open to improvement and can be developed through learning (incremental). Incremental beliefs, indirectly through a task goal orientation, and entity beliefs directly, predicted self-reported amotivation towards physical education and sport. On the other hand, enjoyment of physical activity in youth was predicted directly by task orientation and incremental beliefs. Predictions concerning the moderating role of perceived competence were not supported. Our findings highlight the importance of ability beliefs and goals in understanding the determinants of physical activity in children and youth. 相似文献