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1.
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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健美操作为课间操锻炼内容的可行性研究 总被引:1,自引:0,他引:1
对 90名中学生进行为时 5个月系统的健美操作为课间操锻炼内容的实验 ,运用观察统计等方法证明健美操作为课间操的内容比广播操更有利于提高大脑皮层的兴奋性、灵活性和学习效率。为今后健美操代替广播操的进一步推广、普及提供理论依据。 相似文献
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网络型电子期刊编目原则探讨 总被引:12,自引:0,他引:12
网络型电子期刊的编目原则问题是进行该类型资源编目首先要解决的问题,本文针对网络型期刊的特点探讨了两种原则以及相应的著录要求,即:单记录原则(在印刷版/原始记录中给出访问路径);为网络版期刊单独建立记录的原则。笔者建议采用后者,并讨论了网络型电子期刊的著录信息源的选取。 相似文献
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This study explored how members of competing host communities may endorse different acculturation orientations towards valued and devalued immigrants settled in the bilingual city of Montreal. Francophone (N=422) and Anglophone (N=401) host community students from low-, medium- and high-ethnic diversity colleges completed the host community acculturation scale (HCAS) along with a questionnaire monitoring a range of social psychological correlates of acculturation orientations. Results showed that Anglophones were more integrationist and individualist and less assimilationist than Francophones. Both Francophones and Anglophones were more integrationist and individualist and less assimilationist, segregationist and exclusionist toward valued than devalued immigrants. Attending a multiethnic college had no influence on respondents’ acculturation orientations. The more welcoming acculturation orientations of Anglophones compared to Francophones was corroborated by results obtained with immigrants attending the French and the English colleges. Social psychological profiles of the respective acculturation orientations were similar across both host communities thus supporting the construct validity of the HCAS. Attitude toward co-national outgroup was a significant determinant of each acculturation orientations, suggesting that intergroup relations between rival host communities has an impact on acculturation orientations toward immigrants. 相似文献