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1.
David Sánchez-Oliva Rebecca M. Leech Alberto Grao-Cruces Irene Esteban-Cornejo Carmen Padilla-Moledo Oscar L. Veiga 《Journal of sports sciences》2020,38(9):1062-1069
ABSTRACTThe aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time. 相似文献
2.
David Kaldewey 《Minerva》2018,56(2):161-182
This article analyzes the concept of “grand challenges” as part of a shift in how scientists and policymakers frame and communicate their respective agendas. The history of the grand challenges discourse helps to understand how identity work in science and science policy has been transformed in recent decades. Furthermore, the question is raised whether this discourse is only an indicator, or also a factor in this transformation. Building on conceptual history and historical semantics, the two parts of the article reconstruct two discursive shifts. First, the observation that in scientific communication references to “problems” are increasingly substituted by references to “challenges” indicates a broader cultural trend of how attitudes towards what is problematic have shifted in the last decades. Second, as the grand challenges discourse is rooted in the sphere of sports and competition, it introduces a specific new set of societal values and practices into the spheres of science and technology. The article concludes that this process can be characterized as the sportification of science, which contributes to self-mobilization and, ultimately, to self-optimization of the participating scientists, engineers, and policymakers. 相似文献
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William James (1919) characterises hypotheses as either live or dead. A hypothesis is live when it is taken into account as a ‘real possibility’. We follow James’ suggestion to not attribute intrinsic properties to hypotheses, but rather investigate how they came into being and look at the effects they generate. Expectations of digital technologies are a topic of vivid debate in the insurance industry. Before these expectations can become ‘live’, they have, in the first place, to be generated by market devices. We investigate how the reinsurance blogpost platform Open Minds functions as an ‘expectation generation device’ on the future of insurance markets. Combining Beckert’s work on the role of fictional expectations with the pragmatist turn in sociology of markets, we propose to study ‘expectation generation devices’, provoking expectations on economic markets. In our empirical analysis, we demonstrate the explicit fictional character of the Open Minds contributions, and analyse how a contained space of openness is generated to provoke expectations. We demonstrate how Open Minds can become live through circulation to other expectation generation sites in the insurance industry and beyond. We conclude by reflecting on the importance of expectation generation devices as a particular type of market devices. 相似文献
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6.
Javier Horcajo David Santos Joshua J. Guyer Rafael Mateos 《Journal of sports sciences》2020,38(19):2242-2252
ABSTRACT To better understand doping-related attitude change, it is important to consider not only the amount of thinking (i.e., elaboration) done by message recipients, but also the favourability of their thoughts in response to the proposal, as well as the perceived validity in their thoughts. The main goal of the present study was to analyse the effects of a meta-cognitive process (i.e., thought validation) on attitudes related to doping. Thus, we randomly assigned participants to read a message either against or in favour of legalising several doping behaviours. Participants listed their thoughts regarding the proposal and indicated the perceived validity in their thoughts, then reported their attitudes. As hypothesised, the message against legalisation elicited more unfavourable thoughts and attitudes than the message in favour of legalisation. Most relevantly, the effects of the message direction on attitudes were greater for participants with higher (vs. lower) levels of thought validity. Furthermore, consistent with the thought validation process, results revealed that thought favourability was a better predictor of attitudes for participants with higher (vs. lower) perceived thought validity, indicating that perceiving one’s thoughts as valid plays an important role in persuasion. These findings provide novel insights for research and interventions regarding doping in sports. 相似文献
7.
David C. Berliner 《Journal of Personnel Evaluation in Education》1990,4(1):75-90
8.
Measuring Search Engine Quality 总被引:12,自引:3,他引:9
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures. 相似文献
9.
David Pearson 《Health information and libraries journal》2001,18(3):139-143
This paper addresses the need to recognize the importance, and the challenges, of preserving the hugely expanding record of medicine today for historians of the future. We are faced not only with an increase in traditional publishing formats, but also with the rapid growth in electronic communications. Two celebrated medical cases, one from the late seventeenth century and one from the late twentieth, are used to illustrate the differences and the difficulties. The need for active and effective professional collaboration is stressed; libraries should work together to address these issues. 相似文献
10.