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21.
Asier Mañas Borja del Pozo-Cruz Francisco José García-García Amelia Guadalupe-Grau 《European Journal of Sport Science》2017,17(7):940-953
Sedentary behaviour (SB) has recently emerged as an independent risk factor for different health outcomes. Older adults accumulate long time in SB. Understanding the role that SB plays on health is crucial for a successful aging. This short systematic review summarizes the current evidence related to the effects of objectively measured SB on frailty, physical performance and mortality in adults ≥60?years old. The literature search produced 271 records for physical performance (n?=?119), frailty (n?=?31), and mortality (n?=?121). Finally, only 13 articles fulfilled the inclusion criteria and were included in this review. All articles but one included in the physical performance section (n?=?9) showed a negative association between longer time spent in SB and physical performance. A significant association of SB with higher odds of frailty was found, however this association disappeared after adjusting for cognitive status. Lastly, two of the three included studies showed positive associations between SB and mortality, but this effect decreased or even disappeared in the more adjusted models. In conclusion, there is consistency that SB is negatively associated with physical performance. However, the relationship between objectively measured SB and frailty incidence and mortality rates remains unclear and deserves further research. The use of homogenous criteria to assess SB and the inclusion of more robust research designs will help clarifying the independent effects that SB could have on physical performance, frailty, and mortality. This will ultimately help designing more efficient and comprehensive physical activity guidelines for older adults. 相似文献
22.
In many Western science systems, funding structures increasingly stimulate academic research to contribute to practical applications,
but at the same time the rise of bibliometric performance assessments have strengthened the pressure on academics to conduct
excellent basic research that can be published in scholarly literature. We analyze the interplay between these two developments
in a set of three case studies of fields of chemistry in the Netherlands. First, we describe how the conditions under which
academic chemists work have changed since 1975. Second, we investigate whether practical applications have become a source
of credibility for individual researchers. Indeed, this turns out to be the case in catalysis, where connecting with industrial
applications helps in many steps of the credibility cycle. Practical applications yield much less credibility in environmental
chemistry, where application-oriented research agendas help to acquire funding, but not to publish prestigious papers or to
earn peer recognition. In biochemistry practical applications hardly help in gaining credibility, as this field is still strongly
oriented at fundamental questions. The differences between the fields can be explained by the presence or absence of powerful
upstream end-users, who can afford to invest in academic research with promising long term benefits. 相似文献
23.
Paolo Bardella Irene Carrasquilla García Marco Pozzo Julio Tous-Fajardo Eduardo Saez de Villareal 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(1):102-114
The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality. 相似文献
24.
This paper analyzes the effects that the 2012 VAT rise in Spain had on household’ demand for cultural goods and services. Household’ demands are modeled as a two-stage QUAIDS. After estimating price and expenditure elasticities, and the pass-through parameter associated with the reform, our results show that the individual welfare loss and the increment in the tax bill increase, but less than proportionately, with income. Consequently, the reform can be considered as regressive. Relating the effects of the VAT reform to households’ incomes also implies a low quantitative effect, because of the low proportion of total household expenditure that cultural expenditure represents. From a social perspective, the size of the induced welfare loss would positively depend on society’s inequality aversion. Regardless of the latter, it cannot be concluded whether the reform would have increased or reduced inequality in the distribution of cultural spending. Our results prove qualitatively robust to alternative values of the pass-through parameter. 相似文献
25.
26.
Manuel Belver Ana Ulln María Acaso 《The International Journal of Art & Design Education》2005,24(1):93-99
In this article, a basic controversy for art education in Spain is analysed, and its antecedents in thought and social and artistic practices are reviewed. The controversy refers to the question whether school art education should be oriented towards the fine arts or towards the manual arts. Consequently, which should be the cultural model of reference in contemporary art education? These two controversies are considered as two dimensions whose poles have, to a certain extent, the capacity to articulate various educational trends. The values associated with each pole of each dimension are discussed: for the first dimension, creativity, originality, self‐efficacy and the value of accomplished work; for the second, increase of cultural capital and intercultural solidarity. Finally, the possibility is considered of elaborating educational models that would integrate the various mentioned educative values. The question is raised of the compatibility of these educational values, and it is pointed out that art education has the capacity to generate educational spaces of interchange and dialogue in which to combine languages and perspectives that can contribute to human development and to the mutual coexistence of social groups. 相似文献
27.
28.
“健康儿童?健康社会”(HCSC)是在欧盟体育健康发展准则下,构建由家庭、学校、体育组织、地区政府等诸多部门组成的复合体系,通过降低BMI值减少超重,改善运动能力,进而提高个人生活质量。主要通过对HCSC项目的历史发展进行论述,对HCSC的核心理念、组织构架、运作模式3方面进行剖析,并以中国实验学校为例,对实验干预前后学生的身体健康指标进行对比分析,旨为国内相关领域研究抛砖引玉。 相似文献
29.
Jiří Baláš David Giles Jan Kodejška Michaela Panáčková Simon Fryer 《European Journal of Sport Science》2016,16(7):764-772
This study aimed to (1) evaluate the effect of hand shaking during recovery phases of intermittent testing on the time–force characteristics of performance and muscle oxygenation, and (2) assess inter-individual variability in the time to achieve the target force during intermittent testing in rock climbers. Twenty-two participants undertook three finger flexor endurance tests at 60% of their maximal voluntary contraction until failure. Performances of a sustained contraction and two intermittent contractions, each with different recovery strategies, were analysed by time–force parameters and near-infrared spectroscopy. Recovery with shaking of the forearm beside the body led to a significantly greater intermittent test time (↑ 22%, P?.05), force–time integral (↑ 28%, P?.05) and faster muscle re-oxygenation (↑ 32%, P?.05), when compared to the hand over hold condition. Further, the ratio of intermittent to continuous test time distinguished specific aerobic muscular adaptations among sport climbers (2.02), boulderers (1.74) and lower grade climbers (1.25). Lower grade climbers and boulderers produced shorter duration contractions due to the slower development of target force during the intermittent test, indicating worse kinaesthetic differentiation. Both the type of recovery and climbing discipline determined muscle re-oxygenation and intermittent performance in rock climbers. 相似文献
30.
David?PassigEmail author Jenny?Maidel-Kravetsky 《Education and Information Technologies》2016,21(3):531-543
The aim of this study was to determine whether, as a result of collaborative-online reading of a chapter from a book of an academic nature, the quality of the collaborative summary that the readers would write would be higher than that written by readers who would both read the same chapter and write a summary in a face-to-face setting. In this study we examined the difference between the summaries written by participants from two groups, each group was divided into subgroups of 3 participants who had read collaboratively a chapter of a book, and collaborated on writing a summary. The participants of the experimental group read the chapter as it appeared in a website for collaborative reading built especially for this study and the participants were asked to summarize the chapter on a shared online digital document. The participants of the control group were asked to read the chapter face-to-face and to collaboratively summarize it in hand writing. The quality of the summaries was evaluated with a tool developed by Rivard (2001). This tool was developed to measure the quality of the summaries. In our study the main and secondary ideas that were supposed to be included in the participants’ summaries were identified by three literature teachers using ten different criteria and the summaries were analyzed by two other judges based on these criteria. The findings indicated that there were significant differences in the majority of the writing indicators being measured with the tool. The findings indicated that collaborative-online reading and writing produce a summary of a higher quality than one read and hand written collaboratively face-to-face. 相似文献