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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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Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7–8 years later.  相似文献   
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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   
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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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中国竞技体育人力资源相关问题探讨   总被引:5,自引:0,他引:5  
对竞技体育人力资源的概念、特点等问题进行了探讨:研究表明,竞技体育人力资源是指竞技体育发展所需人员的现实及潜在禀赋的总和。处于不同层次、不同领域的众多人员组成了竞技体育人力资源系统:竞技人力资源具有稀缺性、目标性、整体性及调控性等特点.  相似文献   
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国内运动生物力学发展现状思考   总被引:5,自引:0,他引:5  
运动生物力学是一门新兴的边缘性科学,其定义、研究范畴、研究方法都有待商榷。从这三个角度出发,主要对大量资料进行归纳总结,综合、概括了目前国内运动生物力学发展状况。力求对我国的运动生物力学发展的状况勾勒出一个清晰的脉络图,以便在这门学科今后的研究中减少盲目性,具有更强的实用性。  相似文献   
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奥运会的经济价值分析以及对北京举办奥运会的借鉴意义   总被引:11,自引:1,他引:10  
2008年北京奥运会的举行将大大加快北京地区乃至我国的经济现代化建设的步伐。应用实证研究的方法,对历届奥运会的经济价值进行分析,指出举办奥运会对促进北京地区乃至全国的经济增长、改善劳动力就业,加快产业结构调整的积极作用。同时从资金筹措、场馆建设、产业可持续发展等方面对北京避免奥运会后可能出现的“经济低谷效应”,实现可持续发展提出了建议。  相似文献   
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