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181.
Triin Rääsk Kenn Konstabel Jarek Mäestu Evelin Lätt Toivo Jürimäe Jaak Jürimäe 《Journal of sports sciences》2015,33(16):1649-1657
We examined the tracking of physical activity (PA) measured by accelerometers and subjective self- and parental reports in normal weight and overweight and obese pubertal boys over two-year period. In total, 156 boys with mean (±SD) age of 11.53 ± 0.76 at baseline and with mean age of 13.94 ± 0.74 at 2 year follow-up were studied. At baseline and approximately two years later, the boys completed self-report questionnaire and wore an accelerometer for seven consecutive days. On the basis of first year assessment’s body mass index (BMI), the children were grouped as normal weight and overweight and obese groups according to BMI cut-offs. Tracking correlations of objectively measured PA and subjectively measured PA were fairly similar across the 12–14 year-old-boys weight groups over two year period. Tracking correlations of objectively measured PA and subjectively measured PA were not significantly different over two-year period between both BMI groups. The results of the study show that pubertal boys objectively measured PA decreased over two-year period and so the boys started to be less active in their pubertal period. 相似文献
182.
Martin K. Klämpfl Philipp B. Philippen Babett H. Lobinger 《Journal of sports sciences》2015,33(7):655-664
The yips is considered a task-specific movement disorder. Its estimated prevalence, however, is high compared to similar neurological movement disorders, possibly resulting from previous studies’ restriction of samples based on skill level, and self-report bias. Alternatively, this high prevalence might be an indication of additional aetiologies, for example the influence of previously played racket sports. We estimated the prevalence of the putting yips across the skill range, using self-reports in one study and a screening test in a second study. We explored if previously played sports matter for the development of the yips. In study 1, yips prevalence (N = 1,306) and golfers’ sports biographies (n = 264) were examined via two online surveys, in which golfers indicated if they were yips-affected. In study 2, golfers (N = 186) putted in a standardised putting test while kinematic and performance measures were recorded. Prevalence was estimated via a kinematic threshold. Sports biographies (n = 119) were obtained via an online survey. Prevalence of currently yips-affected golfers was 22.4% in study 1 and 16.7% in study 2. In both studies, more yips-affected than unaffected golfers had experience in playing racket sports. Yips prevalence remained higher than previously estimated prevalence of other movement disorders but decreased when the whole skill range including professionals and novices was considered. Future studies should use the kinematic screening test instead of self-reports to detect the yips and further investigate the influence of previously played racket sports. 相似文献
183.
Thomas G. Martin Rachel W. Pata Johanna D’Addario Lauren Yuknis Rebecca Kingston Richard Feinn 《Journal of sports sciences》2015,33(19):1988-1997
This study investigated whether haematological markers differ between young and masters marathon participants, running at similar performance levels. Nine young (31.89 ± 4.96 years) and eight masters (63.13 ± 4.61 years) runners participated. At five time points (pre-race through 54 h post-race), a complete blood cell count, basic metabolic panel and creatine kinase (CK) isoenzyme panel were assessed. Race performance was standardised using the World Masters Association Age Grading Performance Tables. Total CK levels were elevated for all participants at all time points post-race (P < 0.001). The CK-isoenzyme MB% was elevated across groups at 6, 30 and 54 h post-race (P < 0.01, P < 0.01 and P < 0.05), with masters runners having a higher CK-MB% at 30 and 54 h (P < 0.05, P < 0.05). Total white blood cell and neutrophil counts were elevated through 6 h post-race (P < 0.001), with higher levels found in younger runners (P < 0.001). When considering all blood work, masters runners had a higher number of abnormal values at 6, 30 and 54 h post-race (P < 0.05, P < 0.01 and P < 0.05). In conclusion, masters runners demonstrated sustained CK-MB elevation, which may suggest greater cardiac stress. However, future studies using additional cardiac markers should be completed to confirm these findings. In addition, masters runners showed an increased number of laboratory values outside normal range, indicating the body’s reduced capacity to respond to marathon running. 相似文献
184.
Martin Johnes 《国际体育史杂志》2015,32(15):1784-1798
Archives and the documents within them are at the heart of the practice of history and the occupational culture of historians. A majority of historical work has been characterized and defined by research in archives of varying kinds. Yet, the material within archives is both partial and political and using it is never straightforward. For historians of sport, the material available in archives can be especially limited but, with some careful reading between the lines, there is still much to learn from and interpret within traditional archives. This paper explores the different kinds of archives and archival material that historians of sport have used and the uses they have been and can be put to. Archives, however, are not static entities and the paper also discusses the impact and implication of digitization processes and programmes to popularize and legitimize traditional archives. Although sport has been seen as one of the ways of diversifying the content and audience of archives, the paper argues that the practical and interpretative challenges historians of sport face in archives are no different to those faced by other historians. 相似文献
185.
Big and open linked data analytics ecosystem: Theoretical background and essential elements 总被引:1,自引:0,他引:1
Big and open linked data are often mentioned together because storing, processing, and publishing large amounts of these data play an increasingly important role in today's society. However, although this topic is described from the political, economic, and social points of view, a technical dimension, which is represented by big data analytics, is insufficient. The aim of this review article was to provide a theoretical background of big and open linked data analytics ecosystem and its essential elements. First, the key terms were introduced including related dimensions. Then, the key lifecycle phases were defined and involved stakeholders were identified. Finally, a conceptual framework was proposed. In contrast to previous research, the new ecosystem is formed by interactions of stakeholders in the following dimensions and their sub-dimensions: transparency, engagement, legal, technical, social, and economic. These relationships are characterized by the most important requisites and public policy choices affecting the data analytics ecosystem together with the key phases and activities of the data analytics lifecycle. The findings should contribute to relevant initiatives, strategies, and policies and their effective implementation. 相似文献
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187.
This paper describes a newly adapted instrument for measuring novice-to-expert-like perceptions about biology: the Colorado Learning Attitudes about Science Survey for Biology (CLASS-Bio). Consisting of 31 Likert-scale statements, CLASS-Bio probes a range of perceptions that vary between experts and novices, including enjoyment of the discipline, propensity to make connections to the real world, recognition of conceptual connections underlying knowledge, and problem-solving strategies. CLASS-Bio has been tested for response validity with both undergraduate students and experts (biology PhDs), allowing student responses to be directly compared with a consensus expert response. Use of CLASS-Bio to date suggests that introductory biology courses have the same challenges as introductory physics and chemistry courses: namely, students shift toward more novice-like perceptions following instruction. However, students in upper-division biology courses do not show the same novice-like shifts. CLASS-Bio can also be paired with other assessments to: 1) examine how student perceptions impact learning and conceptual understanding of biology, and 2) assess and evaluate how pedagogical techniques help students develop both expertise in problem solving and an expert-like appreciation of the nature of biology. 相似文献
188.
基于显微图像的金标试纸条测试线线宽参数的测量方法具备操作方便、测量速度快、分辨率高等优点,然而图像采集系统采集到的金标试纸条的显微图像不可避免地会发生倾斜,这为后续的图像分割和参数测量带来了困难,因此需要对倾斜的金标试纸条显微图像进行校正。根据霍夫变换法和最小二乘法在直线检测中的优点和适用条件,拟采用一种结合霍夫变换法和最小二乘法的直线检测算法来求得金标试纸条图像的边缘线和边缘线的倾斜角度参数,并采用图像旋转变换算法实现对原图像的倾斜校正。实验表明,所采用的倾斜校正算法具备计算量小、占用内存小、校正精度高的优点,通过倾斜校正可以准确测量倾斜金标试纸图像的线宽参数。 相似文献
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190.