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121.
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.  相似文献   
122.
Cased explosives generate highly energetic fragments as their casing breaks up. Due to the complexity of casing fragment related behavior such as embedment, perforation and ricochet, it may be insufficient to use equivalent triangular pressure loading in fragment impact simulations. This simplified method may over- or under-predict the target response. Recently, a procedure using contact techniques has been proposed to overcome such difficulties. It has been shown that the new method has the inherent capability in modeling the multi-piece and multi-hit fragment impact problems in a more realistic way. To investigate the applicability of the proposed method to simulations involving multi-layer penetration, the selected problems of fragment impact on multi-layer targets are described in this paper. It is demonstrated that this method is capable of predicting the complicated multi-layer structural response caused by fragment impact and penetration. Modeling procedures and some technical issues are also discussed.  相似文献   
123.
124.
Learning support assistants (LSAs) gained more political and academic attention in Britain after Estelle Morris announced that schools of the future would include more trained staff to support learning to higher standards. LSAs, thus, should form an integral part of the culture of all school departments in Britain, including physical education (PE). The paper uses Antonio Gramsci's concept of hegemony to explore the processes and practices that shape the views and experiences of LSAs and ultimately the extent to which they facilitate an inclusive culture in PE. A web survey gathered the views and experiences of LSAs vis-à-vis the inclusion of pupils with special educational needs (SEN) in mainstream secondary school PE in North-West England. A modified version of the tailored design method participant contact strategy resulted in 343 LSAs starting the web survey, with 154 (45%) following it through to completion. All quantitative data were analysed using Microsoft Excel whilst qualitative data were subjected to thematic analysis. This entailed the identification of recurring themes and patterns present in the data. The findings highlight the hegemonic status of English, maths and science when it comes to the allocation of SEN resources, which most LSAs support and often reinforce. PE is particularly disadvantaged in this hierarchy of subject priority. The majority of LSAs have not received PE-specific training, which brings into question their ability to facilitate inclusion in PE. Moreover, many schools do not appear to value the involvement of LSAs in the planning of differentiated lessons, which could have a negative impact on the PE experiences of some pupils with SEN given that LSAs are perhaps most aware of the specific learning needs of the pupils they support.  相似文献   
125.
Red or dead     
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126.
Soccer is a sport not commonly associated with the Dominican Republic given the positioning of baseball as the national game. Yet, for some migrant groups in the country, such as those from Haiti, soccer plays an important part in their lives. Haitians have used soccer as a way to unite their communities and establish a sense of place. This paper assesses how these Haitian migrants use the game as a means of creating a community and developing a common focal point. Through participant observations and semi-structured interviews, this work may help us construct new understandings of the ways in which migrants use sport to assimilate to new surroundings and retain links to home.  相似文献   
127.
Purpose: The present study aimed to determine if autonomic cardiac modulation was influenced by acute exposure to normobaric hypoxia. Method: Ten healthy male lowland dwellers completed five block-randomised single-blinded, crossed-over acute exposures to a normobaric hypoxic environment, each separated by 24 hours’ recovery (20.3%, 17.4%, 14.5%, 12.0% and 9.8% FIO2). Supine recordings were made of arterial oxygen saturation and electrocardiogram (ECG). RR intervals from the ECG trace were analysed for time (SDNN, lnrMSSD), frequency (lnVLF, lnLF, lnHF, lnTP, LFnu, and HFnu), and nonlinear (DFA-α1 and SampEn) heart rate variability components. Results: A significant reduction in arterial SaO2 occurred with reduced FIO2, along with a rise in heart rate (Cohen’s d?=?1.16, 95% Confidence Interval [2.64–6.46]), significant at 9.8% FIO2. A decrease in autonomic cardiac modulation was also found as shown by a statistically significant (at 9.8% FIO2) decrease in lnTP (d?=?1.84 [1.74–1.94]), and SampEn (d?=?0.98 [0.83–1.12]) and an increase in DFA-α1 (d?=?0.72 [0.60–0.84]) from normoxia at 9.8% FIO2. Conclusion: The decrease in variability indicated a reduction in autonomic cardiac modulation. There appears to be a threshold ~9.8% FIO2 (~6000?m equiv.), below which significant alterations in autonomic control occur.  相似文献   
128.
The present paper focuses on the application of a structured template, maximum impact flow (MIF), in order to encourage young students in the area of optics and optical engineering. MIF introduces a template in terms of individual steps and linked functionality and is shown to fuse separate learning tools together into a cohesive unit. Prioritization and teaching structures are also discussed with the promotion of technology identified as a key factor.  相似文献   
129.
ABSTRACT

Blended learning has been a feature of higher education practice and research for almost two decades. This article takes stock of current blended learning research, contributing to the growing number of meta-analyses of higher education and blended learning research more generally, through a review of ninety-seven articles relating to blended learning in higher education published in fifteen journals between 2012 and mid-2017. The review focused on where and when the articles were published; their provenance, scale, scope; methodological approach; the broad research themes; and definition of blended learning used. The review shows that despite its ubiquity, blended learning’s definition is all-encompassing; its spread is global but research is dominated by key players; it is of technical interest; and its research is small-scale, individually focused, seeking to evidence the benefits of blended learning. The article concludes with recommendations of how higher education research could provide institutions with evidence to ensure their ‘best of blends’.  相似文献   
130.
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