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761.
Pavle Mikulić Tomislav Smoljanović Ivan Bojanić Jo Hannafin Zbreveeljko Pedisbreveić 《Journal of sports sciences》2013,31(4):361-366
Abstract In this study, we assessed the extent to which 2000-m rowing ergometer performance predicted final rankings at the World Junior Rowing Championship in a sample of 398 junior rowers competing in 13 events. The rowers' ergometer performance times were examined using a questionnaire, and in all 13 events they correlated (P ≤ 0.039) with the final rankings at the Championship. The strongest correlations were observed for ergometer performance times in junior women's single sculls (r = 0.92; P < 0.001), followed by junior men's single sculls (r = 0.80; P < 0.001) and junior women's double sculls (r = 0.79; P < 0.001). The observed correlations were higher for smaller boats – singles, doubles, and pairs (r = 0.64–0.92; P ≤ 0.025) – than for larger boats – quads, fours, and eights (r = 0.31–0.70; P ≤ 0.039). Linear regression analyses were used to construct regression equations to predict final rankings based on 2000-m rowing ergometer performance times for each event. Although correlations in 10 of the 13 events were above r = 0.5, the large standard errors of the estimate impaired the prediction of rankings in all of the studied events. Using these equations, the most probable rowing ergometer performance times required for a particular ranking in a given rowing event might easily be calculated. 相似文献
762.
Abstract Little is known of the performance characteristics of the shotokan karate mae-geri kick. The aim of this study was to compare the execution time, the lower limb kinetics and kinematics, and their respective repeatability in the mae-geri kick of karate athletes of two different standards. Seventeen adult black belt karate competitors (9 national and 8 international athletes) performed six kicks with their dominant lower limb on a striking surface, combining maximum force impact and velocity. Execution time of movement and lower limb kinematics were recorded with a high-speed camera. Maximum force at impact and the forces exerted on the ground were measured using three force plates. The duration of the kick was significantly shorter for international than for national standard athletes. However, no significant difference in the maximum impact force of the kick was observed between the two groups. In addition, significant kinematic differences were observed between the groups, with two angles of motion and one velocity peak occurring sooner in the kick movement for the international athletes, specifically for the knee joint. International athletes also performed the kick with a significantly higher repeatability for duration and kinematics, specifically during the pre-loading phase that precedes the attack phase. We conclude that theduration of the kick and repeatability of lower limb kinematics could be useful in selecting top-level karate athletes and monitoring their training status. 相似文献
763.
Manuel J. Coelho-E-Silva Vasco Vaz Filipe Simões Humberto M. Carvalho João Valente-Dos-Santos António J. Figueiredo 《Journal of sports sciences》2013,31(16):1793-1802
Abstract Characteristics of 32 international and 41 local under-17 (U-17) (14.5–16.5 years) roller hockey players were considered in the context of discrimination by competitive level using training history, anthropometry, skeletal maturation, and several laboratory and field performance tests. More international (42%) than local (22%) players were advanced in maturity status. International players had slightly less hockey experience (years), but had more practice sessions and match time (minutes) during the season. Local players were shorter and attained better performance in the 25-m dash, while international players performed better in sit-ups, ball throw and 20-m shuttle run. The fatigue index derived from the Wingate anaerobic test was higher among local players, while peak torques of knee extension and flexion were greater in international players. Stepwise discriminant function correctly classified 85% of players by competitive level based on grip strength, ratio of eccentric and concentric knee extension, number of training sessions, playing time and fatigue index. The results suggested an interaction among strength, anaerobic fitness and training plus game time as factors in discriminating international from local level players and by inference in the selection and development of youth roller hockey players. 相似文献
764.
Aurélio Faria Ronaldo Gabriel João Abrantes Paola Wood Helena Moreira 《Journal of sports sciences》2013,31(14):1559-1567
Abstract We investigated the mechanical properties of the triceps surae between professional, junior, and non-football players. Fifty-nine men participated in this study. The mechanical properties of the right legs’ triceps surae were measured in vivo using a free oscillation technique; no significant differences existed between the groups. The mean results for musculo-articular stiffness, damping coefficient, and damping ratio were as follows: professional football players (21523 N· m?1, 330.8 N · s · m?1, and 0.201); junior football players (21063 N · m?1, 274.4 N · s · m?1, and 0.173); and non-players (19457 N · m?1, 281.5 N · s · m?1, and 0.184). When analysed according to position, the results were as follows: defender (21447 N · m?1, 308.6 N · s · m?1, and 0.189); midfielder (20762 N · m?1, 250.7 N · s · m?1, and 0.157); winger (21322 N · m?1, 335.1 N · s · m?1, and 0.212); forward (22085 N · m?1, 416.2 N · s · m?1, and 0.254); and non-players (19457 N · m?1, 281.5 N · s · m?1, and 0.184). Thus, football training, football games, and the position played had no effect on triceps surae mechanical properties. These results may be attributed to opposing adaptations between different types of training that are usually implemented in football. Alternatively, the minimum strain amplitude and/or frequency threshold of the triceps surae required to trigger adaptations of mechanical properties might not be achieved by football players with football training and matches. 相似文献
765.
Elisabeth E. Kraemer Susan C. Davies Kelli Jo Arndt Sawyer Hunley 《Psychology in the schools》2012,49(2):163-175
Attending to instruction is a critical behavior for academic success. Many elementary school teachers, however, identify disruptive and inattentive classroom behaviors as key barriers to students' successful educational performance. This study examined the impact of two class‐wide positive behavior support programs. The Mystery Motivator and Get 'Em On Task interventions were implemented in an alternating treatments design with fifth grade participants to decrease off‐task behaviors. Results indicated that both interventions effectively decreased off‐task behavior at the class‐wide level. Implications and suggestions for future research on evidence‐based behavioral interventions are discussed. © 2011 Wiley Periodicals, Inc. 相似文献
766.
Cloud-Hansen KA Kuehner JN Tong L Miller S Handelsman J 《CBE life sciences education》2008,7(3):302-309
The goal of the work reported here was to help students expand their understanding of antibiotic resistance, the Central Dogma, and evolution. We developed a unit entitled "Ciprofloxacin Resistance in Neisseria gonorrhoeae," which was constructed according to the principles of scientific teaching by a team of graduate students, science faculty, and instructors. A variety of activities and assessments were used, including a case study, short lectures, and group problem-solving. Implementation of "Ciprofloxacin Resistance in Neisseria gonorrhoeae" in a college freshman seminar suggests these materials are useful in increasing understanding of complex biological topics and improving problem-solving abilities. 相似文献
767.
The aim of this study was to investigate the influence of perceived student gender on the feedback given to undergraduate student work. Participants (n = 12) were lecturers in higher education and were required to mark two undergraduate student essays. The first student essay that all participants marked was the control essay. Participants were informed that the control essay was written by Samuel Jones (a male student). Participants then marked the target essay. Although participants marked the same essay, half of the participants (n = 6) were informed that the student essay was written by Natasha Brown (a female student), while the remaining participants were informed that it was written by James Smith (a male student). In-text and end-of-text feedback were qualitatively analysed on six dimensions: academic style of writing; criticality; structure, fluency and cohesion; sources used; understanding/knowledge of the subject; and other. Analysis of feedback for both the control and target essay revealed no discernible differences in the number of comments (strengths of the essay, areas for improvement) made and the content and presentation of these comments between the two groups. Pedagogical implications pertaining to the potential impact of anonymous marking on feedback processes are discussed. 相似文献
768.
João Palotti Allan Hanbury Henning Müller Charles E. KahnJr. 《Information Retrieval》2016,19(1-2):189-224
The internet is an important source of medical knowledge for everyone, from laypeople to medical professionals. We investigate how these two extremes, in terms of user groups, have distinct needs and exhibit significantly different search behaviour. We make use of query logs in order to study various aspects of these two kinds of users. The logs from America Online, Health on the Net, Turning Research Into Practice and American Roentgen Ray Society (ARRS) GoldMiner were divided into three sets: (1) laypeople, (2) medical professionals (such as physicians or nurses) searching for health content and (3) users not seeking health advice. Several analyses are made focusing on discovering how users search and what they are most interested in. One possible outcome of our analysis is a classifier to infer user expertise, which was built. We show the results and analyse the feature set used to infer expertise. We conclude that medical experts are more persistent, interacting more with the search engine. Also, our study reveals that, conversely to what is stated in much of the literature, the main focus of users, both laypeople and professionals, is on disease rather than symptoms. The results of this article, especially through the classifier built, could be used to detect specific user groups and then adapt search results to the user group. 相似文献
769.
Martins João Onofre Marcos Mota João Murphy Chris Repond Rose-Marie Vost Helen Cremosini Bruno Svrdlim Andjelko Markovic Mojca Dudley Dean 《Prospects》2021,50(1-2):13-30
PROSPECTS - This paper addresses the inadequate understanding of the concept of physical literacy (PL), often originating from complex terminology and philosophical language used in the current... 相似文献
770.
Reading and Writing - Using hierarchical linear models, this study probes into student, family, teacher, and schools’ variables that can explain the variation in Progress in International... 相似文献