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The aim of this study was to determine whether gait cycle characteristics are associated with running economy in elite Kenyan runners. Fifteen elite Kenyan male runners completed two constant-speed running sets on a treadmill (12 km ·h?1 and 20 km ·h?1). VO2 and respiratory exchange ratio values were measured to calculate steady-state oxygen and energy cost of running. Gait cycle characteristics and ground contact forces were measured at each speed. Oxygen cost of running at different velocities was 192.2 ± 14.7 ml· kg?1· km?1 at 12 km· h?1 and 184.8 ± 9.9 ml· kg?1· km?1 at 20 km· h?1, which corresponded to a caloric cost of running of 0.94 ± 0.07 kcal ·kg?1·km?1 and 0.93 ± 0.07 kcal· kg?1· km?1. We found no significant correlations between oxygen and energy cost of running and biomechanical variables and ground reaction forces at either 12 or 20 km· h?1. However, ground contact times were ~10.0% shorter (very large effect) than in previously published literature in elite runners at similar speeds, alongside an 8.9% lower oxygen cost (very large effect). These results provide evidence to hypothesise that the short ground contact times may contribute to the exceptional running economy of Kenyan runners.  相似文献   
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We analyze the so-called Socialism of the twenty-first century in which nine South American governments turned to the left over the last 15 years. This South American socialist turn is seen as a delinking from the logics of dependency and pure neoliberalism. To explore the rhetorics that underlie this delinking process, we conducted both a macroanalysis and an intradiscursive rhetorical analysis of the inauguration and most significant speeches of all of the leftist South American presidents elected after 1999. We claim that a common critique of neoliberalism underlies the South American presidents’ speeches, which manifests through specific rhetorics concerning participatory democracy, social inclusion, and environmental protection. When they became transnational, these delinking rhetorics crafted a decolonial critique that calls for more indigenous models of development.  相似文献   
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Virtual microscopy (VM) is a widely used teaching method in Medical Education in many developed countries. In Brazil, however, this is not the case for most medical schools, considering Brazilian social inequality and uneven access to technology. Recently, the Covid-19 pandemic has also challenged Universities to seek and make a transition toward more effective methods of full-time online education. Thus, the main goal of this work was to verify student's perception and academic performance, assessed upon VM implementation in a Brazilian Medical School. Ribeirao Preto Medical School students answered a 26-question survey with regards to optical microscopy (OM) and VM. Academic performance was compared between participants that were (year of 2019) or were not (year of 2015) exposed to VM. Taken the results together, subjective impressions such as handling, suitability, learning effectiveness, and pleasure using the tools, have shown a higher score for virtual microscopy (median = 29), when compared to optical microscopy (median = 24) with a P-value < 0.001 by Wilcoxon rank test, upon measurement using an ordinal scale. Regarding academic performance, no statistically significant differences were found between groups (P-value = 0.38, Cohen's d = 0.19). Therefore, VM proved to be adequate to the Brazilian medical education in light of Brazilian social contexts and Covid-19 pandemic.  相似文献   
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The literature on Cultural Economics provides us with some examples for the measurement of technical efficiency. However, there are few case studies dedicated to the analysis of allocative efficiency. The aim of this paper is to fill this gap by incorporating a methodology that analyses both technical and allocative efficiency. We use the Shephard’s distance function, particularly suitable when affronted with non-profit-making firms or institutions that are not interested in cost minimization. As an empirical application, we analyse the efficiency of Fundación Princesa de Asturias (PAF), a Spanish non-governmental organization devoted to promoting the cultural, scientific and humanistic values of universal heritage, the period of study being 1988–2012. Our findings suggest that PAF could have used 7% less inputs to achieve the same level of output. On the other hand, we have found allocative inefficiency. Concretely, the input for other expenditures appears to have been over-utilized in relation to both the inputs for labour and current assets, with labour in turn being over-utilized in relation to current assets. Moreover, our results indicate that both technical and allocative efficiency have clearly improved during the period analysed. In summary, our empirical application shows how distance function methodology can be successfully implemented to measure allocative efficiency in cultural firms and institutions.  相似文献   
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European Journal of Psychology of Education - Children’s motivation to master challenging tasks is an important predictor of school success, and yet, such motivation declines during...  相似文献   
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选择LaFeSi作为基础,在其中添加过渡族元素Co,配制成LaFe11.7-xCoxSi1.3 Bo.25(X =0.6,0.65)系列合金,采用高频磁悬浮感应加热炉进行熔炼,进行热处理,并对样品在1.5T磁场下进行直接测量.结果表明,Co元素的适量添加,对提高居里温度有意义,也可以适当调整材料的绝热温变,对于保持材料的磁热性能有更好的作用.  相似文献   
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