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1.
ABSTRACT

The 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.
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published.  相似文献   
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坐式排球是残疾人奥运会正式比赛项目,2000年我国把坐式排球列为全国残疾人运动会正式比赛项目。经过五年的发展,我国坐式排球运动水平已进入世界六强行列。为了完成2008年北京残奥会上男女双获金牌的战略目标,当前最重要的工作就是加强二线队伍的建设,加大运动员的选材力度。经过三年的跟队研究,总结出坐式排球运动员选材的特殊性:放宽运动员的年龄界限,要求队员有较长的上体和上肢。残障程度:以小腿截肢和两下肢不等长的运动员最适合参加坐式排球运动的训练。在挑选攻手时,注意残障腿与扣球手成反向;在挑选二传手时,残障腿是右腿的运动员更适合。  相似文献   
6.
The is article analyses the two main approaches for artists’ selection in the recording industry: the direct model in which large major companies directly choose new artists from the supply market, and the agency model in which small independent labels realise the first choice and, subsequently, large organisations pick their new artists among those pre-selected by independents.An empirical analysis of chart sales reveals that artists selected through the agency model exhibit a longer presence on the chart due to repeated successes, while they are slower to reach heavy success once they have entered the chart. Conversely, the direct model leads to artists with a faster path to a strong success, but the same artists have a shorter presence on the chart due to the sporadic nature of their success. The profile of artists selected through these two models is also found to be different: big international soloist stars are more frequently selected through the direct model, while national bands are more frequently selected through the agency model.The insights suggest important implications for management in the cultural industries and especially in the recording industry. Jel Codes: L82; O32  相似文献   
7.
体育明星作形象代言人推行品牌产品的战略效应分析   总被引:2,自引:0,他引:2  
运动鞋企业是晋江经济的支柱,其发展对晋江经济和体育产业的发展有着重要的意义。值此第七届晋江(国际)鞋业博览会之际,运用文献资料、调查访问、观察及网上查询等研究方法,并运用经济学、广告学等相关学科的一些原理,分析了福建晋江运动鞋企业聘请体育明星作形象代言人推行品牌建设的现状及存在的一些主要问题,并提出了进一步推动晋江运动鞋企业品牌建设的一些对策和建议,以便给当地政府及相关的决策者提供一些理论参考。  相似文献   
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The validity and reliability of curriculum‐based measures in reading as indicators of performance and progress for secondary‐school students were examined. Thirty‐five grade 8 students completed reading aloud and maze‐selection measures weekly for 10 weeks. Criterion measures were the state standards test in reading and the Woodcock–Johnson III Test of Achievement. Different time frames for each measure were compared. Most alternate‐form reliability coefficients were above .80. Criterion‐related validity coefficients ranged from .77 to .89. No differences related to time were found. Only maze selection reflected significant growth, with an average increase of 1.29 correct choices per week. Maze growth was related to the reading performance level and to change on the Woodcock–Johnson III from pre‐ to posttest.  相似文献   
9.
王乐 《大学图书馆学报》2022,40(1):97-101+114
从红色专题特藏概念的界定出发,论述了红色专题特藏在人才培养、科学研究、社会服务方面的重要意义:红色专题特藏是思政教育的生动教材,是科学研究的重要素材,是社会服务的鲜活题材。复旦大学图书馆在历史积累的基础上,通过捐赠、采购、收集等方式建设了时间跨度大、类型多样、主题丰富的红色专题特藏。采取参与式、阵地化思政教育,多形式、全方位驱动科研,立体化、全媒介大众推广的三大举措九种手段,挖掘红色专题特藏的全方位价值,在红色基因传承、红色资源研究、红色文化传播等方面发挥作用。  相似文献   
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