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Many of the socio-cultural lifestyle and dietary changes that take place during Ramadan may affect the risk of injury in athletes, but little evidence is available. The aim of the present study was to examine the effects over two consecutive years of the holy month of Ramadan on injury rates in 42 professional players of a Tunisian top-level professional soccer team. Players were retrospectively organized into fasting and non-fasting groups and monitored for 3 months: 4 weeks before Ramadan, during the month of Ramadan (4 weeks), and 4 weeks after Ramadan each year. During Ramadan, training started at 22.00 h. The circumstances (training/match) and mechanism of injury (traumatic/overuse) were recorded. No significant differences between the three periods were observed for weekly mean training load, training strain, training duration, and Hooper's Index (quality of sleep, and quantities of stress, delayed-onset muscle soreness, and fatigue). Compared with non-fasting players, fasters had a lower (P < 0.05) Hooper's Index and stress during and after Ramadan. No significant difference in injury rates was observed between fasting and non-fasting players. Nevertheless, the rates of non-contact (6.8 vs. 0.6 and 1.1) and training overuse (5.6 vs. 0.6 and 0.5) injuries were significantly higher in fasting players during the month of Ramadan than before or after Ramadan. In conclusion, Ramadan, along with the corresponding changes in nutritional habits, sleeping schedule, and socio-cultural and religious events, significantly increased overuse and non-contact injuries in fasting players despite the fact that the training load, strain, and duration were maintained. 相似文献
43.
Appropriate intellectual property protection and economic growth in countries at different levels of development 总被引:1,自引:0,他引:1
This paper examines how the role of patents and utility models in innovation and economic growth varies by level of economic development. Using a panel dataset of over 70 countries, we find that patent protection is an important determinant of innovation and that patentable innovations contribute to economic growth in developed countries, but not in developing. Instead, in developing economies, a minor form of intellectual property rights (IPRs) - namely utility models - is conducive to innovation and growth, controlling for other factors. Using Korean firm level data as a case study, we find that utility model innovations contribute to firm performance when firms are technologically lagging and that those minor innovations can be a learning device and thus a stepping stone for developing more patentable inventions later on. Upon reaching higher levels of technological capabilities, firms become more reliant upon patents and less on utility models. Thus the lesson here is that patent protection enhances innovation and economic growth in countries where the capacity to conduct innovative research exists. Where this capacity is weaker, a system that provides incentives to conduct minor, incremental inventions is more conducive to growth. The significance of this paper is to emphasize the importance not just of the strength of IPRs but of the appropriate type of IPRs for economic development. 相似文献
44.
This study attempts to model the growth behavior of the number of publications and patents of South Korea, Taiwan, Japan and Malaysia. Three competing growth functions, namely, simple logistic growth function, bi-logistic growth function and logistic function within a dynamic carrying capacity were considered. The findings provide insight to the diffusion process of science and technology, often measured by the number of publications and patents, respectively. The function that provides the best fit to the observed data was opted for explaining the diffusion process. The function with the best fit is the bi-logistic growth function for the number of publications as well as the number of patents of South Korea and Taiwan, the logistic growth function within a dynamic carrying capacity (LGDCC) for the number of publications and the bi-logistic growth function for the number of patents of Japan, and the LGDCC for the number of publications and simple growth function for the number of patents of Malaysia. The results suggest a dynamic self-propagating growth for the science and technology, and thereby a transition from science and technology-push to market-pull growth for South Korea and Taiwan. While a similar transition was observed for the technology of Japan, the growth in science had entered a maturity stage. On the other hand, the growth potential in science is dynamic for Malaysia, but its technological advancement is relatively lower and static compared to the other economies. 相似文献
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A great obstacle for wider use of structural equation modeling (SEM) has been the difficulty in handling categorical variables. Two data sets with known structure between 2 related binary outcomes and 4 independent binary variables were generated. Four SEM strategies and resulting apparent validity were tested: robust maximum likelihood (ML), tetrachoric correlation matrix input followed by SEM ML analysis, SEM ML estimation for the sum of squares and cross-products (SSCP) matrix input obtained by the log-linear model that treated all variables as dependent, and asymptotic distribution-free (ADF) SEM estimation. SEM based on the SSCP matrix obtained by the log-linear model and SEM using robust ML estimation correctly identified the structural relation between the variables. SEM using ADF added an extra parameter. SEM based on tetrachoric correlation input did not specify the data generating process correctly. Apparent validity was similar for all models presented. Data transformation used in log-linear modeling can serve as an input for SEM. 相似文献
48.
This study investigates the socialization and professional experiences of primary school physical education teachers (PSPETs) in the Asian context of Hong Kong. A qualitative research design is adopted. The researcher used semi-structured interviews, supplemented by documentary sources (diaries) for conducting data collection. Eleven PSPETs participated in this study. Data were analysed through open axial and selective coding. The concepts of organizational sensitivity, sources of satisfaction, dealing with influential persons or critical incidents, status of the profession, educational reform as a trend, and versatile roles are revealed in the theory of ‘Diversified Professionalism’. The substantive theory thus contributes to an increased appreciation of the PSPETs’ work and to the literature on physical education teachers’ professionalization and professionalism. 相似文献
49.
Qianqian Zhou Tze Ping Loh Tony Badrick Chun Yee Lim 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
IntroductionIt is unclear what is the best strategy for applying patient-based real-time quality control (PBRTQC) algorithm in the presence of multiple instruments. This simulation study compared the error detection capability of applying PBRTQC algorithms for instruments individually and in combination using serum sodium as an example.Materials and methodsFour sets of random serum sodium measurements were generated with differing means and standard deviations to represent four simulated instruments. Moving median with winsorization was selected as the PBRTQC algorithm. The PBRTQC parameters (block size and control limits) were optimized and applied to the four simulated laboratory data sets individually and in combination.ResultsWhen the PBRTQC algorithm were individually optimized and applied to the data of the individual simulated instruments, it was able to detect bias several folds faster than when they were combined. Similarly, the individually applied algorithms had perfect error detection rates across different magnitudes of bias, whereas the error detection rates of the algorithm applied on the combined data missed smaller biases. The performance of the individually applied PBRTQC algorithm performed more consistently among the simulated instruments compared to when the data were combined.DiscussionWhile combining data from different instruments can increase the data stream and hence, increase the speed of error detection, it may widen the control limits and compromising the probability of error detection. The presence of multiple instruments in the data stream may dilute the effect of the error when it only affects a selected instrument. 相似文献
50.
The perspective of six Malaysian students on playing video games: Beneficial or detrimental? 总被引:1,自引:0,他引:1
Roselan Baki Eow Yee Leng Wan Zah Wan Ali Rosnaini Mahmud Mohd. Sahandri Gani Hamzah 《美中教育评论》2008,5(11):11-21
This study provides a glimpse into understanding the potential benefits as well as harm of playing video games from the perspective of six Malaysian secondary school students, aged 16-17 years old. The rationale of the study is to enable parents, educators, administrators and policy makers to develop a sound understanding on the impact of playing video games before making any judgment on the contemporary youth culture. Thus, further decision on the acceptance of video games as a new innovation in school or at home could be considered. Although this study is not very extensive, the findings suggest that playing video games contributes to cognitive, social, motivational and emotional development. However, potential harms do exist. Parents play an important role in guiding their children either directly or indirectly, as indicated by the respective students. Caution is advised in the interpretation of the study's findings as it is solely based on the perspectives of the students, as the first person's views. Nevertheless, each student has their very own perspective on the impact of video games on them. 相似文献