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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.
Edgardo Ferretti Leticia Cagnina Viviana Paiz Sebastián Delle Donne Rodrigo Zacagnini Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181
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prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove).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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María Inés Tato 《档案与原稿》2020,48(2):200-215
ABSTRACT This paper aims to analyse the initiatives undertaken by some immigrant communities residing in Latin America to record their mobilisation around the First World War. After the armistice, European communities in Argentina, Bolivia, Brazil, Chile, Mexico, Paraguay, Peru, Uruguay and other countries gathered detailed information about their activities during the conflict, published as profusely illustrated books of remembrance, offered to their governments as proof of their loyalty. The article intends to establish the peculiar nature of these publications as records of the war effort, and analyse the agents and processes of their elaboration, and their role as commemorative but also as archival documents. 相似文献
5.
秦历史环境变迁与关中民族传统体育发展 总被引:2,自引:0,他引:2
采取文献资料、逻辑分析等方法,研究了秦由部落生活、奴隶社会向封建社会的历史环境变迁及其在关中的民族分布状况,从而探析秦关中民族传统体育的发展.结果表明:秦经历了由小到大、由弱到强的曲折发展及社会形态的演变,以关中为政治、经济、文化、军事中心,建都570余年,最终统一全国,实现民族大融合,关中民族传统体育的发展随着秦的历史环境变迁而变化. 相似文献
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对参加2000年全国男子拳击冠军赛的56名拳击运动员和185名男大学生的心电图进行分析,结果显示:运动员组心电图异常(不包括窦性心动过缓和左室高电压)低于对照组;窦性心动过缓、左室高电压、不完全右束枝传导阻滞的发生率非常显地高于对照组;平均安静心率非常显地低于对照组;而二组窦性心律不齐的发生率无显差异,说明拳击运动员心血管系统具有强大的适应能力。 相似文献
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目的探讨食管癌患者年龄、吻合位置与术后并发症发生率和死亡率的关系,以及新辅助化疗对食管癌手术切除率的影响。方法回顾性分析西安交通大学医学院第一医院肿瘤外科自1997年~2003年首诊收治、资料完整587例食管癌患者资料。结果不同年龄组手术切除率分别为91.2%、95.9%和97.7%(P>0.05);>70岁年龄组术后吻合口瘘发生率和术后死亡率均较其它组高(P<0.05)。胸膜顶部吻合口瘘发生率为16.67%,较其它位置吻合口瘘发生率明显高(颈部2.17%、弓上1.09%、弓后2.60%、弓下0),具有显著性差异(P=0.019)。III期食管癌患者行术前新辅助化疗组与未化疗组的手术切除率分别为96.92%和78.85%,具有显著差异(P<0.05),而术后吻合口瘘发生率和术后死亡率无明显差异(P=1.000)。结论术前新辅助化疗可提高食管癌手术的切除率并不增加术后并发症。年龄大并不完全是手术禁忌,高龄患者的手术应充分考虑患者的生理年龄。 相似文献