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991.
Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body. 相似文献
992.
In order to identify factors associated with on-field moral functioning among student athletes within the unique context of football, we examined masculine gender role conflict, moral atmosphere, and athletic identity. Using structural equation modeling to assess survey data from 204 high school football players, results demonstrated that moral atmosphere (i.e., the influence of coaches and teammates) was significantly associated with participants' process of on-field moral functioning across the levels of judgment, intention, and behavior. Neither masculine gender role conflict nor athletic identity significantly predicted moral functioning, but the results indicated that participants' identification with the athlete role significantly predicted conflict with socialized gender roles. Results suggest that in the aggressive and violent sport of football, coaches can have a direct influence on players' moral functioning process. Coaches can also have an indirect effect by influencing all the players so that a culture of ethical play can be cultivated among teammates and spread from the top down. 相似文献
993.
V. B. Saputra S. K. Ong A. Y. C. Nee 《上海大学学报(英文版)》2014,(3):222-230
This paper presents a calibration method for parallel manipulators using a measurement system specially installed on an external fixed frame. The external fixed frame is important as an error reference for calibration in certain operations, such as in the configuration of a parallel manip- ulator functioning as a machine tool where the workpiece is fixed to a worktable. The pose of the end-effector is mea- sured using three digital indicators installed on the external fixed frame. To enable measurement, the end-effector is assumed to be a plane large enough that all digital indicators could touch. The error is defined as the difference between the theoretical and actual readings of the digital indicators. The geometric parameters of the parallel manipulator are optimized to minimize this error. This calibration method is low cost and feasible for compensating geometric parameter errors for a parallel manipulator. Optimal pose selection for the calibration is achieved using a swarm intelligence search algorithm. The method is implemented on a prototype of a six degrees-of-freedom (DOFs) Gough-Stewart platform constructed to function as a machine tool. 相似文献
994.
Torres-Martín César Acal Christian El-Homrani Mohammed Mingorance-Estrada Ángel C. 《Educational technology research and development : ETR & D》2022,70(3):909-929
Educational technology research and development - The objective has been to know the impact of the flipped classroom methodology on the academic performance of students during their training... 相似文献
995.
Educational Psychology Review - The purpose of this systematic review is to describe the state of the art of sequential multiple-assignment randomized trials in education research. An iterative,... 相似文献
996.
Mazon Cécile Etchegoyhen Kattalin Saint-Supery Isabeau Amestoy Anouck Bouvard Manuel Consel Charles Sauzéon Hélène 《Educational technology research and development : ETR & D》2022,70(1):231-262
Educational technology research and development - In recent years, many psycho-educational technologies were studied to address the school-related difficulties encountered by students with autism... 相似文献
997.
Heilala C. Kalland M. Lundkvist M. Forsius M. Vincze L. Santavirta N. 《Early Childhood Education Journal》2022,50(3):399-409
Early Childhood Education Journal - We studied the working conditions in Early Childhood Education and Care (ECEC). The aim was to explore how ECEC staff experience work demands and resources and... 相似文献
998.
Measure of opportunity: assessing equitable conditions to learn twenty-first century thinking skills
Learning Environments Research - Many school change efforts aim to foster conditions for the development of students’ twenty-first century skills in an equitable and comprehensive way, but... 相似文献
999.
Objective:The primary objective of this study was to determine how community college health sciences librarians perceive their proficiencies in the essential skills, knowledge, and abilities necessary for the practice of a health information professional as defined by the Medical Library Association (MLA) Competencies for Lifelong Learning and Professional Success. A secondary objective was to determine their current level of engagement with the professional community and identify barriers to further professional development.Methods:A survey was posted to various email discussion lists, and volunteer follow-up interviews were conducted.Results:The survey was completed by seventy-five community college health sciences librarians, and seven follow-up interviews were performed. Survey results indicated that community college health sciences librarians perceived themselves as having intermediate or advanced intermediate proficiency in the six MLA competencies. Survey and interview results indicated that community college health sciences librarians were engaged with the profession and faced the same barriers to continued professional development and continued education as other academic librarians.Conclusion:The results affirm that community college librarians who are responsible for collections and services in the health sciences meet the MLA competencies, which fills a gap in the literature regarding how these librarians develop professional competencies and are involved in professional associations. The results suggest that community college librarians can improve their skill levels by continuing their education and following trends in the literature. 相似文献
1000.
评估大学教学发展中心的工作效果有助于高等教育质量的改善。本文首先对教师发展工作的相关研究做了文献述评,随后介绍了密歇根大学学习与教学研究中心开发的项目综合评估模型,并结合具体的项目与服务案例展示了该中心如何记录并评估教师的教学发展工作以及如何借助这些评估结果来改善自身实践。文章最后为中国大学教学中心的建设提供了一些建议。 相似文献