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Early childhood is a sensitive period for learning and social skill development. The maturation of cerebral regions underlying social processing lays the foundation for later social-emotional competence. This study explored myelin changes in social brain regions and their association with changes in parent-rated social-emotional development in a cohort of 129 children (64 females, 0–36 months, 77 White). Results reveal a steep increase in myelination throughout the social brain in the first 3 years of life that is significantly associated with social-emotional development scores. These findings add knowledge to the emerging picture of social brain development by describing neural underpinnings of human social behavior. They can contribute to identifying age-/stage-appropriate early life factors in this developmental domain. 相似文献
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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
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In this digital ITEMS module, Dr. Jeffrey Harring and Ms. Tessa Johnson introduce the linear mixed effects (LME) model as a flexible general framework for simultaneously modeling continuous repeated measures data with a scientifically defensible function that adequately summarizes both individual change as well as the average response. The module begins with a nontechnical overview of longitudinal data analyses drawing distinctions with cross-sectional analyses in terms of research questions to be addressed. Nuances of longitudinal designs, timing of measurements, and the real possibility of missing data are then discussed. The three interconnected components of the LME model—(1) a model for individual and mean response profiles, (2) a model to characterize the covariation among the time-specific residuals, and (3) a set of models that summarize the extent that individual coefficients vary—are discussed in the context of the set of activities comprising an analysis. Finally, they demonstrate how to estimate the linear mixed effects model within an open-source environment (R). The digital module contains sample R code, diagnostic quiz questions, hands-on activities in R, curated resources, and a glossary. 相似文献
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电大生《经济数学基础》课程学习困难的成因分析 总被引:1,自引:0,他引:1
潘红卫 《广西广播电视大学学报》2003,14(4)
本文对电大生《经济数学基础》课程学习困难的成因进行了分析,并对教师在该课程教学中要注意的问题提出了几点建议。 相似文献
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新形势下高校篮球教学改革的思路 总被引:8,自引:1,他引:7
本文面对高校扩大招生和高校篮球文化的迅猛发展 ,以及上篮球课的学生人数逐年大幅度增加的新形式 ,探讨并提出了教学目标注重兴趣、习惯和能力培养 ,练习要求弹性化 ,知识传授实践化 ,测评方法综合化、团体化 ,准备活动专项化 ,按水平分组练习 ,教学内容精简化、实用化以及练习手段娱乐化、健身化等篮球教学改革的思路。 相似文献
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应重视短距离速滑运动员的有氧能力训练 总被引:4,自引:4,他引:0
通过分析王曼丽运动成绩提高的原因,指出了有氧能力的提高所起的作用,并介绍了王曼丽有氧能力训练的方法,阐明了必须重视短距离速滑运动员的有氧能力训练,才能使达到一定程度的运动水平得到进一步地提高。 相似文献
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