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1.
The aim of the study was to determine if sex differences exist in the key elbow and wrist joint injury risk factors during different cartwheel (CW) and round-off (RO) techniques performed by young male and female artistic gymnasts. Sixteen active young gymnasts (8 males and 8 females) performed 30 successful trials of CW and RO with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic and kinetic data were collected for each trial. Two-way repeated measures ANOVA (3 × 2, technique × sex) and effect-sizes (ES) were used for statistical analysis. In conclusion, female gymnasts exhibited greater normalised peak vertical ground reaction forces (VGRF), elbow and wrist compression forces and elbow internal adduction moments during CW and RO skills compared with male gymnasts. In both sexes, the parallel and reverse techniques increased peak VGRF, elbow and wrist compression forces and the elbow internal adduction moment. Increased elbow flexion resulted in decreased peak VGRF, elbow compression forces and elbow internal adduction moment. Injury risk factors including elbow extension and internal adduction moment with axial compression force suggest that a CW and RO in reverse and parallel techniques can be hazardous especially for young female gymnasts.  相似文献   
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Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
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ABSTRACT

The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists.  相似文献   
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The construction of a history curriculum for England and for Wales under the terms of the 1988 Education Reform Act occasioned more debate in the media than any other subject in the National Curriculum. The links between the content of a history syllabus and perceptions within both nations of the part this plays in moulding national spirit made this inevitable. The disparity of view between the two groups charged with devising the syllabus and the government, particularly the Prime Minister, heightened the tension. This article explores the way in which consequent political, professional and public discussion was covered in the whole range of national newspapers. It is argued that the failure of the London press to comprehend the situation in Wales reduced significantly its appreciation of the processes involved in the making of the history curriculum.  相似文献   
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This paper reports on efforts aimed toward the development of more effective procedures for identifying mothers who are at elevated risk for problems in parenting. We present data from two independent samples of known maladaptors and corresponding comparison mothers and report on our attempts to cross-validate a promising screening instrument composed of items that index social support and parenting attitudes. The resultant 20-item scale correctly identified over 90% of maladaptive and comparison mothers. When this scale was cross-validated on a second independent sample of maladaptors and comparison mothers, it was again almost 90% accurate. Issues concerning the field application of this promising instrument are discussed and its possible limitations are considered.  相似文献   
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Selective universities regularly employ policies that favor children of alumni (known as legacies) in undergraduate admissions. Since alumni from selective colleges and universities historically have been disproportionately white, admissions policies that favor legacies have disproportionately benefited white students. For this reason, legacy policies lead to additional costs in terms of reductions in racial diversity. As larger numbers of minority students graduate from colleges and universities and have children, however, the potential pool of legacy applicants will change markedly in racial composition. This analysis begins with a review of the history and objectives of the preference for children of alumni in undergraduate admissions. We then consider the specific case of the University of Virginia and employ demographic techniques to predict the racial composition of the pool of potential legacy applicants to the university. Significant changes in the racial composition of classes that graduated from the University of Virginia from the late 1960s through the 1970s foreshadow similar changes in the characteristics of alumni children maturing through the next two decades.  相似文献   
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