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41.
Abstract

The aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively.  相似文献   
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Although little is known about learning disabilities (LDs) in English language learners (ELLs), there is a substantial knowledge base about the identification, assessment, and intervention of and for LDs in monolingual native English‐speaking students. Building on this knowledge, participants at an October 2003 National Symposium on Learning Disabilities in English Language Learners were asked to suggest research questions, priorities, and suggestions on how to build the necessary infrastructure to address critical research needs. In the discussions that took place, important themes emerged: (1) identification and assessment of LD and/or reading disabilities (RD) in ELLs (ELL/Ds), (2) understanding of the language and literacy developmental trajectories of ELLs, (3) understanding of the individual and contextual factors affecting outcomes, (4) the intersection of all of these areas with neurobiology, and (5) developing and testing the effectiveness of interventions for learning disabilities in ELL/Ds. These themes, and the research agenda that was forged around them, are presented. In addition, the practice implications of this agenda are presented, along with some suggestions for current practice while we await future research findings.  相似文献   
44.
Students’ writing problems are a global educational concern and is in need of particular attention. This study aims to examine the impact of providing extra writing opportunities (i.e., writing journals) on the quality of writing compositions. A longitudinal cluster-randomized controlled design using a multilevel modeling analysis with 182 fourth grade students was conducted. We examined whether students’ writing quality differed when writing journals on a weekly basis for 12 weeks, compared with a control group. Three covariates were analyzed, namely: (i) the students’ attitudes towards writing; (ii) their self-efficacy in writing; (iii) and their use of self-regulation (SRL) strategies while writing. Findings have shown that students who wrote week-journals significantly improved the writing quality of their compositions and reported a higher use of SRL strategies in writing. Nevertheless, self-efficacy and attitude towards writing were found to not be related to the quality of the compositions. Moreover, data indicated that the writing quality of compositions improved along with the writing quality of the week-journals. Findings suggest the use of week-journals in class to promote writing.  相似文献   
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This study evaluates a performance-based instructional coaching model intended to improve teacher pedagogy and classroom organization for educating diverse student populations. Elementary teachers (N = 21) participated in a 30-h workshop and seven individual coaching sessions across an academic year. The coaching model promoted use of the Standards for Effective Pedagogy, five research-based practices known to increase student achievement. Findings demonstrate performance-based instructional coaching led to statistically significant (a) improvements in teacher pedagogy, (b) patterns of teacher growth, and (c) changes in classroom organization. Implications for improving teachers’ ultimate achievement, the coaching protocol, and research are addressed.  相似文献   
47.
Library and information (LIS) education is undergoing a major transformation. During this time of change, there is a pressing need for data from all stakeholder groups to support strategic decisions within individual schools and across the discipline as a whole; students are a key stakeholder group. This paper reports on a 4-year study of master's students enrolled in an institution undergoing a transition toward an iSchool. The self-administered questionnaire was distributed to students enrolled in the Master of Information Studies program at the University of Toronto eight times: to incoming students in the fall term for 4 years, and to the entire student body in the spring term of those same years. The data collected from approximately 1000 questionnaires indicate that students arrive excited about the information professions and optimistic about employment opportunities. As they progress through the program, however, many are not satisfied with professional aspects of their program. They want courses that prepare them for their first professional position, and opportunities to gain experience, which they believe will increase their employability. The data from the 4-year period revealed fluctuations over the years, which indicates the value of examining longitudinal data.  相似文献   
48.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   
49.
Many services can be self-provided. An individual user or a user firm can, for example, choose to do its own accounting - choose to self-provide that service - instead of hiring an accounting firm to provide it. Since users can ‘serve themselves’ in many cases, it is reasonable to suspect that they can also innovate with respect to the services they self-provide - possibly without the assistance of service providers.In this paper, we conduct the first quantitative exploration of the importance of services innovation by users, focusing on the field of commercial and retail banking services. We find that 55% of today's computerized commercial banking services were first developed and implemented by non-bank firms for their own use, and 44% of today's computerized retail banking services were first developed and implemented by individual service users rather than by commercial financial service providers. Manual precursors to these services - manual procedures that carried out functions similar to computerized services in our sample - were almost always developed by users as self-services.Our empirical findings differ significantly from prevalent producer-centered views of service development. We speculate that the patterns we have observed in banking with respect to the major role of users in service development will prove to be quite general. If so, this will be an important matter: on the order of 75% of GDP in advanced economies today is derived from services. We discuss the implications of our findings for research and practice in service development.  相似文献   
50.
Software must evolve in order to adapt to new demands and scenarios. In the case of packaged software that can be customized, this evolution implies the maintenance of both out-of-the-box and customized functionality alike. New user interface technologies provide a way to interact with applications that software vendors are forced to incorporate in order to meet new user and market requirements. Packaged software vendors are facing software evolution processes in order to attract more customers and conserve the existing ones. This case analysis describes the evolution of packaged software, Meta4 PeopleNet, towards the addiction of Rich Internet Applications features to a Human and Intellectual Capital Management tool. The findings and lessons learned presented in this case study provide useful insights for packaged software vendors facing software product evolution.  相似文献   
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