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191.
The wrist is the most frequently injured body region among snowboarders. Studies have shown that the risk of sustaining a wrist injury can be reduced by wearing wrist protection. Currently, there are a wide variety of wrist protection products for snowboarding on the market that offer a range of protective features. However, there are no minimum performance standards for snowboarding wrist protectors worldwide. The International Society for Skiing Safety convened a task force to develop a White Paper to evaluate the importance and necessity of a minimum performance for all wrist protectors used in snowboarding. The White Paper outlines the need for a general framework for a harmonized international standard and reviews the existing evidence. Therefore, this White Paper may serve as a common base for future discussions. The broader goal of developing and implementing such a standard is to reduce the incidence and the severity of wrist injuries in snowboarding without increasing the risk of adverse events, such as upper arm or shoulder injury. The European standard for inline skating wrist protectors (EN 14120) can serve as a starting point for efforts related to a standard for snowboard wrist protectors, but certain modifications to the standard would be required. It is hypothesized that implementation of a snowboarding wrist protector standard would result in fewer and less severe wrist injuries in the sport and could translate into more riding days for healthy snowboarders and significant health-care costs savings.  相似文献   
192.
This review study focuses on knee injuries in recreational alpine skiing. The objectives of this study were (1) to provide selected knowledge derived from current and past knee injury epidemiology; (2) to outline the most important knee injury mechanisms; and (3) to review and discuss how modifications of the skiing equipment might alleviate the risk of knee injuries. This review represents the essence of a comprehensive research report and considers the content of more than 230 scientific papers, further “grey literature”, patents, international standards and other publications. Knee injuries are the most frequent injuries in alpine skiing and their incidence rate remained high despite a decline of the incidence of other skiing injuries in recent years. Women have a higher knee injury risk, but age and tiredness appear not to be significant factors. Apart from the commonly described injury mechanisms “phantom foot” and “boot-induced anterior drawer” other more sophisticated injury categorisations are given. The ski radius, the ski length and the standing height on the ski may be relevant ski parameters. For the binding, the release mechanisms in different mechanical degrees of freedom, the impact tolerance and the maintenance frequency are discussed. In the ski boot, the height of the upper, the boot liner, the shaft stiffness, and the position on the ski may play a role. The biggest challenge, but probably also the biggest opportunity for a reduction of knee injury rates seems to be the development of a mechatronic binding. The current strategies to develop these types of bindings are explained and illustrated by one example. Some of the possible parameters which may be essential for the necessary control algorithms are described. Finally, considerations regarding the strategic and operational implication of the analysed technical measures are given.  相似文献   
193.
This study characterizes key elements of the start in elite female World Cup skeleton athletes. The top 20 female competitors in three World Cup races were videotaped within a calibrated space to allow the following components of the start to be quantified: (1) acceleration (velocity at 15-m mark, time to 15-m mark), (2) capacity (time to load, total number of steps to load), and (3) load (velocity at 45-m mark). A correlation analysis was used to establish the relationship between the variables of interest and overall start time (15- to 65-m mark). Velocity at the 15-m mark accounted for 86% of the variance in overall start time at St. Moritz and 85% at Sigulda. A stepwise regression analysis revealed that approximately 89% of the variation in start time could be explained by velocity at the 15-m mark, time to load, and velocity at the 45-m mark. Of the variables analysed in this study, rapid acceleration to attain a high velocity at the 15-m mark was the most important component of a fast overall start time. The importance of the time to load and velocity at the 45-m mark vary according to the different track characteristics.  相似文献   
194.
The term technological gender gap refers to the idea that males and females have different technology-related attitudes, behaviors, and skills. This article reviews the mounting evidence documenting the existence of a gender gap, which, if ignored, could render large numbers of female students unprepared to meet the technological challenges of the future. Recommendations for ameliorating the technological gender gap are presented for educators and computer-based instruction (CBI) designers who are interested in providing equitable educational opportunities for male and female students.  相似文献   
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Lammertink  Imme  Boersma  Paul  Rispens  Judith  Wijnen  Frank 《Reading and writing》2020,33(6):1557-1589
Reading and Writing - Visual statistical learning (VSL) has been proposed to underlie literacy development in typically developing (TD) children. A deficit in VSL may thus contribute to the...  相似文献   
197.
This exploratory study foregrounds the important, but often understudied social side of pre-service teacher development and its relation to teaching performance in one university-based teacher preparation program in the US. We examine the extent to which pre-service elementary teachers’ social relationships and perceptions of peer trust and efficacy are associated with performance on a high stakes mathematics teaching assessment. Findings suggest that social and emotional support through close social ties, peer trust, and self-efficacy are significantly and positively associated with pre-service teachers’ teaching performance. Our work further contributes to the development and discourse about teacher education in university-based teacher preparation programs.  相似文献   
198.
Historical texts tell us much about how mathematical concepts and techniques were conceived and evolved. But they can also tell us even more. Usually, their contents embody a pedagogy, specific organizational forms and methods used for teaching mathematics. This article isolates and examines several particular pedagogical techniques: the use of an instructional discourse; a logical sequencing of mathematical problems and exercises and employment of visual aids, evident in historical works. It concludes that much of present day mathematical pedagogy evolved from distant historical antecedents.  相似文献   
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This study tested 2 competing models of friends' influence on the development of delinquency in disruptive boys. In so diong, we examined whether highly disruptive, moderately diseuptive, moderately conforming, and highly conforming boys' delinquecy increased or decreased depeniding on their friends' characteristics. A sample of 868 boys was classified into the 4 groups according to teacher tating at ages 11 and 12. Each group was then subdivided by mutual friends' peer-rate aggressiveness-disturbance at the same ages: aggressive-disturbing friends, average friends, nonaggressive-nondisturbing friends, and no friends. Subgroups were mext compared on self-reported delinquency at age 13 while controlling for average self-reported delinquency and socioeconomic variables at ages 11 and 12. Results indicate that moderately disruptive boys with aggressivedisturbive friends were more delinquent at age 13 than other subgroups of moderately disruptive boys. Highly disrupitve and confroming boys, however, were unaffected by their friends' characteristics. We conclude that the results partially support each theoretical model, suggesting that both individual characteristics and deviant peer association might play causal roles.  相似文献   
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