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261.
The purpose of the current study was to test the factor structure and scale quality of data provided by caregivers about the home environment and child behavior at home using the Elementary School Success Profile (ESSP) for Families. The ESSP for Families is one component of the ESSP, an online social-environmental assessment that also collects information from students and teachers. Confirmatory factor analyses with Mplus and weighted least squares means and variances adjusted estimation took into account the hierarchical nature and ordinal level of the data. The sample comprised caregivers of 692 third- through fifth-grade students from 13 elementary schools in four districts. A primary model and an alternative model were tested. Models were tested on a random calibration sample and validated with another sample. A nine-factor first-order solution demonstrated superior fit to the data. Scores from the nine scales also demonstrated acceptable internal consistency reliability. Implications for practice and further research are presented.  相似文献   
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商代青铜器纹饰具有一定的结构和层次 ,人兽变形、身体简化、蝉纹和吞噬姿态等特征说明其中蕴含着商王变形力量的象征。这种象征着变形力量的纹饰所表现的可能就是高祖夒。  相似文献   
264.
Estimating the risk of infections or other outcomes incident to pathogen exposure is a primary goal of quantitative microbial risk assessment (QMRA). Such estimates are useful to predict population-level risks, to evaluate exposures based on normative or tolerable risk guidelines, and to interpret the likely public health relevance of microbial measurements in environmental media. To evaluate alternative control measures (interventions), ratio estimates of effect (e.g., odds and risk ratios) are needed that are more broadly interpretable in the health sciences and consistent with convention in epidemiology. In this paper, we propose a general method for estimating widely used ratio measures of effect derived from stochastic QMRA approaches, including the generation of appropriate confidence intervals. Such QMRA-derived ratios can be used as a basis for evaluating interventions via hypothesis testing and for inclusion in systematic reviews and meta-analyses in a form consistent with risk estimation approaches commonly used in epidemiology.  相似文献   
265.
The characteristics of infant sleep change over the first year. Generally, infants wake and move less at night as they grow older. However, acquisition of new motor skills leads to temporary increases in night waking and movement at night. Indeed, sleep-dependent movement at night is important for sensorimotor development. Nevertheless, little is known about how movement during sleep changes as infants accrue locomotor experience. The current study investigated whether infant sleep and movement during sleep were predicted by infants' walking experience. Seventy-eight infants wore an actigraph to measure physical activity during sleep. Parents reported when their infants first walked across a room >10 feet without stopping or falling. Infants in the midst of walking skill acquisition had worse sleep than an age-group estimate. Infants with more walk experience had more temporally sporadic movement during sleep and a steeper hourly increase in physical activity over the course of the night. Ongoing motor skill consolidation changes the characteristics of movement during sleep and may alter sleep state-dependent memory consolidation. We propose a model whereby changes in gross motor activity during night sleep reflect movement-dependent consolidation.  相似文献   
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