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排序方式: 共有536条查询结果,搜索用时 15 毫秒
41.
Guillaume Mornieux Dominic Gehring Patrick Fürst Albert Gollhofer 《Journal of sports sciences》2014,32(13):1255-1262
AbstractAnticipatory postural adjustments (APAs), i.e. preparatory positioning of the head, the trunk and the foot, are essential to initiate cutting manoeuvres during football games. The aim of the present study was to determine how APA strategies during cutting manoeuvres are influenced by a reduction of the time available to prepare the movement.Thirteen football players performed different cutting tasks, with directions of cutting either known prior to the task or indicated by a light signal occurring 850, 600 or 500 ms before ground contact.With less time available to prepare the cutting manoeuvre, the head was less orientated towards the cutting direction (P = 0.033) and the trunk was even more rotated in the opposite direction (P = 0.002), while the foot placement was not significantly influenced. Moreover, the induced higher lateral trunk flexion correlated with the increased knee abduction moment (r = 0.41; P = 0.009).Increasing lateral trunk flexion is the main strategy used to successfully perform a cutting manoeuvre when less time is available to prepare the movement. However, higher lateral trunk flexion was associated with an increased knee abduction moment and therefore an increased knee injury risk. Reducing lateral trunk flexion during cutting manoeuvres should be part of training programs seeking the optimisation of APAs. 相似文献
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This paper investigates the conditions when a research joint venture (RJV) will involve a university as a research partner. We hypothesize that larger RJVs are more likely to invite a university to join the venture as a research partner than smaller RJVs because larger ventures are less likely to expect substantial additional appropriability problems to result because of the addition of a university partner and because the larger ventures have both a lower marginal cost and a higher marginal value from university R&D contributions to the ventures’ innovative output. We test this hypothesis using data from the COoperative REsearch (CORE) database, and those data confirm the hypothesis. 相似文献
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Raúl Rigo-Bonnin Noelia Díaz-Troyano Laura García-Tejada Albert Marc-Galindo Míriam Valbuena-Asensio Francesca Canalias 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(1)
Clinicians request a large part of measurements of biological quantities that clinical laboratories perform for diagnostic, prognostic or diseases monitoring purposes. Thus, laboratories need to provide patient’s results as reliable as possible. Metrological concepts like measurement uncertainty and metrological traceability allow to know the accuracy of these results and guarantee their comparability over time and space. Such is the importance of these two parameters that the estimation of measurement uncertainty and the knowledge of metrological traceability is required for clinical laboratories accredited by ISO 15189:2012. Despite there are many publications or guidelines to estimate the measurement uncertainty in clinical laboratories, it is not entirely clear what information and which formulae they should use to calculate it. On the other hand, unfortunately, there are a small number of clinical laboratories that know and describe the metrological traceability of their results, even though they are aware of the lack of comparability that currently exists for patient’s results. Thus, to try to facilitate the task of clinical laboratories, this review aims to provide a proposal to estimate the measurement uncertainty. Also, different suggestions are shown to describe the metrological traceability. Measurement uncertainty estimation is partially based on the ISO/TS 20914:2019 guideline, and the metrological traceability described using the ISO 17511:2020. Different biological quantities routinely measured in clinical laboratories are used to exemplify the proposal and suggestions. 相似文献
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Chih-Chia Chen Shannon D.R. Ringenbach Andrew Albert Keith Semken 《International Journal of Disability, Development & Education》2014,61(1):6-15
The connection between human cognitive development and motor functioning has been systematically examined in many typical and atypical populations; however, only a few studies focus on people with Down syndrome (DS). Twelve adolescents with DS participated and their cognitive control, measured by the Corsi-Block tapping test (e.g., visual working memory), the Auditory Memory span test (e.g., verbal working memory) and the Tower of London test (e.g., cognitive planning), and motor control, measured by the Purdue Pegboard (e.g., fine motor control), were measured in this study. Results indicate that if people with DS have better performance in fine manual dexterity, they will have better performance in cognitive planning and verbal working memory abilities. The co-activation hypothesis of the prefrontal area and the cerebellum may support this positive relationship. Hence, it is suggested people with DS will obtain benefits in cognitive control by participating in further motor intervention. 相似文献
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Recent handbooks of giftedness or expertise propose a plethora of conceptions on the development of excellent performance but, to our knowledge, there are no comparative studies that provide empirical evidence of their validity to guide researchers and practitioners in their adoption of a particular conception. This study sought to close that gap by conducting an empirical comparison of the major approaches to giftedness and expertise currently in use: the IQ model, the performance model, the moderator model, and the systemic model. The four models were tested in a longitudinal study with a sample of N = 350 German students attending university preparatory schools; 25% of the sample had been assigned to special classes for the gifted. The construct and predictive validity of the four models were tested by means of structural equation modeling. Theoretical considerations along with our results indicated a differentiation among the models whereby some could only predict while others could also explain the emergence of excellent performance and thereby yield valuable information for the design of interventions. The empirical comparison of the approaches showed that they were unequally suited for the two challenges. For prediction purposes, the performance approach proved best while, for explanations, the moderator and systemic approaches were the most promising candidates. Even so, the latter did demonstrate conceptual and/or methodological problems. The IQ approach was superseded by the other approaches on both prediction and explanation. Implications and limitations of the findings are discussed. 相似文献
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