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991.
The aim of this study was to examine the influence of level of skill and swimming speed on inter-limb coordination of freestyle swimming movements. Five elite (2 males, 3 females; age 18.9?±?1.0 years, height 1.71?±?0.04?m, body mass 62.1?±?7.0?kg) and seven novice (age 22.0?±?2.0 years, height 1.77?±?0.04?m, body mass 74.8?±?9.0?kg) swimmers swam a sprint and a self-paced 25?m freestyle trial. The swimming trials were recorded by four digital cameras operating at 50 Hz. The digitized frames underwent a three-dimensional direct linear transformation to yield the three-dimensional endpoint kinematic trajectories. The spatio-temporal relationship between the upper limbs was quantified by means of the peak amplitude and time lag of the cross-correlation function between the right and left arm's endpoint trajectories. A strong anti-phase coupling between the two arms, as confirmed by peak amplitudes greater than 0.8, was noted for both groups and swimming speeds. Significantly higher (P <?0.05) peak amplitudes were observed for the sprint compared with self-paced swimming. No significant differences in the strength of inter-limb coupling were noted between the elite and novice swimmers (P >?0.05). Time lags were very close to 0?ms and did not differ between groups or swimming speeds. We conclude that in freestyle swimming, the intrinsic anti-phase (180° phase difference) inter-limb relationship is strongly preserved despite the physically powerful environmental influence of the water and this “preferred” pattern is not affected by level of skill. In contrast, increasing movement speed results in stronger inter-limb coupling that is closer to the anti-phase inter-limb relationship. 相似文献
992.
993.
Abstract In two experiments we examined changes in the perception of action possibilities as a function of exertion. In Experiment 1, participants repeatedly climbed on a climbing wall in a series of trials that progressively increased in number to 10 trials, resulting in increased exertion. Before and during climbing, the participants judged their maximum reaching height and perceived exertion. On a separate day, participants climbed another 10 trials while performing actual maximum reaches. Higher perceived exertion was associated with decreases in perceived maximum reach while the actual reaches did not decrease. However, the perceptual changes occurred early during task execution when the participants were not yet fatigued. When exertion set in, neither perceived nor actual maximum reaching appeared to be affected. In Experiment 2, we included exhaustion trials. The findings replicated the early changes in perception observed in Experiment 1, which may be explained by hands-on experience with the task. Furthermore, while climbing to exhaustion, perceptual judgements largely changed in keeping with changes in the actual maximum reach. Thus, there appeared to be a functional relationship between participants' actual action capabilities, rather than their state of physical fatigue per se, and perceived action possibilities. 相似文献
994.
Sharmila?JayasingamEmail author Mahfooz A?Ansari T?Ramayah Muhamad?Jantan 《知识管理研究与实践》2013,11(3):255-264
Knowledge management (KM) has often been claimed to be an essential ingredient in building competitive advantage. Yet, KM adoption is relatively slow, especially in the Malaysian context. Most organizations are unsure if the promised performance improvement is just a passing fad. This study intends to provide empirical verifications to support the link between KM practices and performance outcomes for organizations. Responses from 180 knowledge-based organizations were analysed. The analysis indicated that knowledge acquisition and knowledge utilization positively influenced strategic and operational improvement in organizations, whereas the positive effect of knowledge dissemination was only evident in the case of strategic improvement. Organization size had some interesting moderating impact on the tested relationships. 相似文献
995.
In a previous issue of Knowledge Management Research & Practice (KMRP), we analysed the content and keywords of all articles published in the first decade of KMRP. With this article, we extend our preliminary analysis to the citation and co-citations made by these articles. The study covers all the 256 articles published. The most cited article was A dynamic theory of organisational knowledge creation by Nonaka. The most cited KMRP article was by Nonaka and Toyama: The knowledge-creating theory revisited: knowledge creation as a synthesizing process. The co-citation analysis of the 100 most cited articles in KMRP publications showed that four groups of topics emerged, one around communities and situated learning, the second group around networks, knowledge transfer and research methods, a third group around the foundations of knowledge management and a fourth group around intellectual capital. 相似文献
996.
997.
This article explores how a subsidiary of a multi-national enterprise (MNE) in an emerging economy embeds with multiple knowledge sources, both in its corporate network (internal) and in the host country (external), to create the capability to undertake innovative activities. Drawing on first-hand and intra-firm field evidence over the lifetime of a subsidiary in the information and communications technology industry in Brazil (1996–2009) the article finds that: (1) Within 10 years, the case subsidiary attained advanced, near-world leading innovation performance in three technological functions: project management, software engineering and product and solutions; (2) This was an outcome of how the firm simultaneously engaged in knowledge-intensive linkages based on increased frequency of use and improved quality over time, with specific internal and external counterparts; (3) However, some counterparts and linkages were more effective than others in contributing to the subsidiary's innovation performance. Drawing on a novel approach that examines the relationship between dual embeddedness and innovative performance, this article extends our understanding of embeddedness as part of knowledge-seeking strategies of MNE-subsidiaries. It also provides new insights to deepen the analysis of the nuances of subsidiaries’ multiple embeddedness, especially in emerging economies. 相似文献
998.
This paper explores varying configurations of knowledge in organisations. A multi-dimensional framework of distinctive forms of knowledge is used to highlight different patterns of organisational knowledge, demonstrating their heterogeneity and variability – over time, in terms of depth of expertise, and their distribution within and between organisations. Common knowledge that is shared across an organisation accounts for only a small proportion of organisational knowledge, indicating that strategies to exploit this resource for competitive advantage will be constrained unless mechanisms are developed that enable access to and transfer of knowledge that is not yet shared or common. 相似文献
999.
Fatma Emel Ko?ak Mustafa Y?ntem ?zlem Yücel Mustafa ?ilo ?zlem Gen? Ayfer Meral 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(2):206-210
Introduction:
Today, the pneumatic tube transport system (PTS) is used frequently because of its advantages related to timing and speed. However, the impact of various types of PTS on blood components is unknown. The aim of this study was to examine the influence of PTS on the quality of routine blood cell counts, erythrocyte sedimentation, and certain blood coagulation tests.Materials and methods:
Paired blood samples were obtained from each of 45 human volunteers and evaluated by blood cell count, erythrocyte sedimentation, and several coagulation tests, including prothrombin time (PT) and activated partial thromboplastin time (aPTT). Blood samples were divided into 2 groups: Samples from group 1 were transported to the laboratory via the PTS, and samples from group 2 were transported to the laboratory manually. Both groups were evaluated immediately by the tests listed above.Results:
The blood sample test results from groups 1 and 2 were evaluated and compared. No statistically significant differences were observed (P = 0.069–0.977).Conclusion:
The PTS yielded no observable effects on blood cell counts, erythrocyte sedimentation, or PT and aPTT test results. We concluded that the PTS can be used to transport blood samples and yield reliable results for blood cell counts, erythrocyte sedimentation, and several coagulation tests. 相似文献1000.
Nora Nikolac Vesna ?upak-Smol?i? Ana-Maria ?imundi? Ivana ?elap 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(3):242-254
Phlebotomy is one of the most complex medical procedures in the diagnosis, management and treatment of patients in healthcare. Since laboratory test results are the basis for a large proportion (60–80%) of medical decisions, any error in the phlebotomy process could have serious consequences. In order to minimize the possibility of errors, phlebotomy procedures should be standardised, well-documented and written instructions should be available at every workstation. Croatia is one of the few European countries that have national guidelines for phlebotomy, besides the universally used CLSI (Clinical Laboratory Standards Institute) H3-A6 Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture; approved Standard-Sixth Edition (CLSI, 2007) and WHO (World Health Organization) guidelines on drawing blood: best practices in phlebotomy (WHO, 2010). However, the growing body of evidence in importance of preanalytical phase management resulted in a need for evidence based revision and expansion of existing recommendations.The Croatian Society for Medical Biochemistry and Laboratory Medicine, Working Group for the Preanalytical Phase issued this recommendation. This document is based on the CLSI guideline H3-A6, with significant differences and additional information. 相似文献