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Purpose: Overuse injuries are common in sport, but complete understanding of injury risk factors remains incomplete. Although biomechanical studies frequently examine musculoskeletal injury mechanisms, human movement variability studies aim to better understand neuromotor functioning, with proposed connections between overuse injury mechanisms and changes in motor variability. Method: In a narrative review, we discuss the variability-overuse injury hypothesis, which suggests repeated load application leads to mechanical tissue breakdown and subsequent injury when exceeding the rate of physiological adaptation. Due to the multidisciplinary nature of this hypothesis, we incorporate concepts from motor control, neurophysiology, biomechanics, as well as research design and data analysis. We therefore summarize multiple perspectives while proposing theoretical relationships between movement variability and lower extremity overuse injuries. Results: Experimental data are presented and summarized from published experiments examining interactions between experimental task demands and movement variability in the context of drop landing movements, along with comparisons to previous movement variability studies. Conclusion: We provide a conceptual framework for sports medicine researchers interested in predicting and preventing sports injuries. Under performance conditions with greater task demands, we predict reduced trial-to-trial movement variability that could increase the likelihood of overuse injuries.  相似文献   
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As a part of efforts to evaluate and monitor the increasing public investment in early childhood education, teachers are being asked to assess children's school readiness. In this study, preschool teachers and kindergarten teachers rated children's skills in three areas (kindergarten readiness, academic skills, and communication skills), and these ratings were compared with direct assessments of the children's skills. Ratings by both groups of teachers tended to be more highly related to basic skills, such as counting and number naming, than to abilities such as solving applied problems and using expressive and receptive vocabulary. Preschool teachers' ratings had a lower association with children's observed skills and abilities than kindergarten teachers' ratings. Ratings of children attending Head Start were systematically inflated, but this relationship was mediated to a significant extent by the teachers' levels of education. More educated teachers rated children in a manner consistent with the children's directly assessed skills. Implications of these findings for informing future efforts to assess school readiness by using teacher ratings are discussed.  相似文献   
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Objective: To determine whether information retrieval might be enhanced by making each component of a structured abstract a separately searchable field. Design: Parallel searches on records arranged so that each abstract could either be searched in its entirety or as a collection of structured fields. Subjects: Records about cardiovascular disease downloaded from MEDLINE and tested against clinical questions derived from a concurrent survey of CD-ROM use in three health science libraries. Intervention: The investigators identified terms used to structure abstracts on MEDLINE and imported the abstracts into an Idealist database prior to searching using keywords from clinical questions. Measurements and main results: recall and precision rates are given for each question in the ‘structured’ and the ‘unstructured’ set of records. Conclusions: Use of structured, rather than unstructured, abstracts improves precision at the ex-pense of recall and places heavier demands upon the searcher’s skill in choosing the correct fields within the abstract to search. Further investigation requires more accurate simulation of MEDLINE software that utilizes features such as MeSH terms, explode, facilities and delimiters.  相似文献   
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Higher education in the United Kingdom is centrally funded, centrally planned, and insulated from market forces. It bears many similarities to the non-market centrally planned economies (CPEs) of the former Soviet Union and Eastern Europe while they struggled to reform but to retain a system of planning and central control. Examination of UK higher education and the CPEs before the transformation to market based systems highlights some of the issues facing higher education today. It also highlights the need for reforms, as well as the difficulties involved in them. Such comparison can also bring home problems faced by reformers in the transition economies.
Despite allegedly extensive reforms in UK higher education, the sector faces problems like those facing the centrally planned economies of Eastern Europe and the former USSR in the 1970s and 80s. Parallels in a number of areas are particularly striking.  相似文献   
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Design-based research for LIS   总被引:2,自引:0,他引:2  
Design-based research is a methodology emerging from the field of education that may hold potential for research in library and information science (LIS). Based upon the assumption that learning is situated in a real-world context, design-based research combines research, design, and practice into one process. It results in usable products that are supported by a theoretical framework. While definitional and methodological issues do exist, the method holds some promise for research into “user-centered” information systems and services. In the field of LIS, design-based research might contribute to our understanding of how people find, choose, understand, and use information in context. The method is also of interest to professionals concerned with “evidence-based practice.” This article will first explain and describe the method as it has been used in the allied field of education. Issues related to definition and methodology will be explored, as well as some of the solutions that have been proposed. The method will then be related to LIS, using the bonded design work of Large, Nesset, Beheshti, and Bowler [Large, A., Nesset, V., Beheshti, J., & Bowler, L. (2006a). Bonded design: a methodology for designing with children. In S. Kurniawan & P. Saphiris (Eds.), Advances in Universal Web Design and Evaluation: Research, Trends and Opportunities. London: Idea Group., Large, A., Nesset, V., Beheshti, J., & Bowler, L. (2006b). “Bonded design”: a novel approach to intergenerational information technology design. Library and Information Science Research, 28, 64–82] as a case study to demonstrate the applicability of design-based research to LIS inquiry.  相似文献   
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In order to assess the current status of MEDLINE training provided by schools of library science, a survey was conducted of those schools having an educational identification code issued by the National Library of Medicine. Information was gathered on such variables as the instructors' background and preparation, the course objectives and content, and the amount of on-line experience provided to students in each of eleven programs. An evaluation of these measures indicates that more opportunities to gain experience in using MEDLINE should be initiated by library schools and that current efforts should be continued and expanded. Specific recommendations for accomplishing these goals are outlined; they are addressed to health sciences librarians, library school educators, the Medical Library Association, and the National Library of Medicine.  相似文献   
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