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901.
Most of what is known about the association between children’s executive function (EF) and school readiness skills is derived from research conducted in Western countries. We tested whether these associations were evident in a middle‐income country context. Participants were 1,480 children, aged 4–7 years old, who participated in an endline assessment of the Tayari program, an early childhood education (ECE) model that is being delivered by the Kenyan education system. High rates of task completion, low rates of floor effects, and high rates of assessor quality ratings supported the feasibility of large‐scale direct assessments of EF with young children. Assessor ratings of children’s attention‐related behaviors during testing were positively associated with their performance on EF tasks (rs = 0.12–0.27). An EF composite score was not related to demographic factors or to children’s exposure to the Tayari program. However, the EF composite score was uniquely associated with performance‐based measures of early literacy (β = 0.18, 95% confidence interval [CI] = 0.05, 0.31), early numeracy (β = 0.16, 95% CI = 0.07, 26), and social‐emotional competencies (β = 0.12, 95% CI = 0.03, 0.20), even after adjustment for multiple covariates. These results are discussed with respect to the ways in which EF skills inform ongoing efforts to invest in ECE in low‐ and middle‐income countries.  相似文献   
902.
Using the Global Trust Inventory, an integrated measure of trust toward 21 relationships and institutions, the structure of trust was explored in four East Asian societies (Mainland China, Japan, South Korea, and Taiwan). The Western model, in which trust is distributed among seven factors representing different branches of society, did not generalize to these East Asian societies, perhaps due to differences in culture and institutional power structures. Instead, two unique structures of trust were identified. Mainland China had a top‐down structure of trust (the China model), in which trust is hierarchically separated between the central government and subordinate implementing bodies. The other three democratic East Asian societies shared a hybrid structure of trust (the Democratic East Asian model) that has a degree of similarity to both the China model and the Western model. Having established two similar, but still distinct models, a cross‐cultural comparison was made on the proportions of trust profiles generated by latent profile analysis. Mainland China had the largest proportion of people with a high propensity to trust, followed by Japan and South Korea, and Taiwan was the least trusting. Implications of the structure of trust and this alternative approach to conducting cross‐cultural comparisons are discussed.  相似文献   
903.
This study investigated the moderating role of proactive coping on the relationship between distress tolerance and elevated blood pressure (BP) among Nigerian adults with heart disease. Two hundred and forty hypertensive patients were recruited from the cardiology unit of a university teaching hospital (females = 56.2%%; mean age = 41.09 years, SD = 9.11 years). The participants responded to two self-reported measure including the Proactive Coping Inventory (PCI) and the Distress Tolerance Scale (DTS). Following moderated regression analysis, the results showed that proactive coping moderated the relationship between distress tolerance and elevated BP. The slope of the moderation analysis indicated that the relationship between distress tolerance and mean artery pressure was significantly higher for individuals with low proactive coping, as compared to individuals with higher proactive coping. Unlike reactive ways of coping, which addressed already existing stress, interventions aimed at increasing peoples’ proactive coping could be more efficacious in the management of people with high BP.  相似文献   
904.
The main purpose of the present study was to test the psychometric properties of the Satisfaction with Life Scale (SWLS) in a large sample of Spanish adolescents. The sample consisted of 1020 non-clinical adolescents with a mean age of 15.96 years (SD = 1.68). The level of internal consistency of the SWLS Total score by means of McDonald’s Omega was .85. The one-dimensional model displayed appropriate goodness of-fit indices. Strong measurement invariance for the one factor model across age and gender was found. Younger adolescents reported higher levels of life satisfaction. In addition, SWLS total score was negatively associated with behavioural and emotional. The study confirmed that the SWLS is a useful tool for the screening of self-reported life satisfaction in adolescents.  相似文献   
905.
Traditional beliefs about two aspects of glucose regulation in the brain have been challenged by recent findings. First, the absolute level of glucose in the brain's extracellular fluid appears to be lower than previously thought. Second, the level of glucose in brain extracellular fluid is less stable than previously believed. In vivo brain microdialysis was used, according to the method of zero net flux, to determine the basal concentration of glucose in the extracellular fluid of the striatum in awake, freely moving rats for comparison with recent hippocampal measurements. In addition, extracellular glucose levels in both the hippocampus and the striatum were measured before, during, and after behavioral testing in a hippocampus-dependent spontaneous alternation task. In the striatum, the resting extracellular glucose level was 0.71 mM, approximately 70% of the concentration measured previously in the hippocampus. Consistent with past findings, the hippocampal extracellular glucose level decreased by up to 30 +/- 4% during testing; no decrease, and in fact a small increase (9 +/- 3%), was seen in the striatum. Blood glucose measurements obtained during the same testing procedure and following administration of systemic glucose at a dose known to enhance memory in this task revealed a dissociation in glucose level fluctuations between the blood and both striatal and hippocampal extracellular fluid. These findings suggest, first, that glucose is compartmentalized within the brain and, second, that one mechanism by which administration of glucose enhances memory performance is via provision of increased glucose supply from the blood specifically to those brain areas involved in mediating that performance.  相似文献   
906.
The present study evaluated cerebral lateralization during Raven's progressive matrices (RPM) paradigm in female and male subjects. Bilateral simultaneous transcranial Doppler (TCD) ultrasound was used to measure mean blood flow velocities (MBFV) in the right and left middle cerebral arteries (MCAs) in 24 (15 females and 9 males) right-handed normal subjects. The female subjects used a left hemisphere strategy, while males used a right hemisphere strategy to successfully solve RPM tasks. This implies that general intelligence is associated with neural systems within one hemisphere that are accessible to a variety of cognitive processes.  相似文献   
907.
The identification of reliable and valid means for evaluating the effectiveness of school-based treatments and completing diagnostic evaluations of middle school aged students are needed. The present study examined the inter-rater agreement of teacher ratings and the relationship between ratings and observational data in a middle school setting. The data are interpreted in the context of differences between a secondary and elementary school setting. Teacher ratings and observational data were collected regularly over the course of two academic years for middle school students diagnosed with ADHD. The results indicate low rates of inter-rater agreement as well as low rates of agreement between teachers and observational data, and between observational data collected in different classrooms. Inter-rater agreement was lowest in late fall and gradually increased over the second half of the year. Implications for conducting treatment outcome evaluations of school-based treatment programs and diagnostic evaluations are discussed.  相似文献   
908.
Three experiments were conducted to investigate the role of central and peripheral vision (CV and PV) in postural control. In Experiment 1, either the central or peripheral visual field were selectively stimulated using a circular random dot pattern that was either static or alternated at 5 Hz. Center of foot pressure (CoP) was used to examine postural sway during quiet standing under both CV and PV conditions. The results showed that, when the visual stimulus was presented in the periphery, the CoP area decreased and more so in the anterior-posterior (AP) than in the medio-lateral (ML) direction, indicating a characteristic directional specificity. There was no significant difference between the static and dynamic (alternating) conditions. Experiment 2 investigated the directional specificity of body sway found in Experiment 1 by having the trunk either be faced toward the stimulus display or perpendicularly to it, with the head always facing the display. The results showed that the stabilizing effect of peripheral vision was present in the direction of stimulus observation (i.e., the head/gaze direction), irrespective of trunk orientation. This suggested that head/gaze direction toward the stimulus presentation, rather than a biomechanical factor like greater mobility of the ankle joint in AP direction than in ML direction, was essential to postural stability. Experiment 3 further examined whether the stabilizing effect of peripheral vision found in Experiments 1 and 2 was caused because more dots (500) were presented as visual cues to the peripheral visual field than to the central visual field (20 dots) by presenting the same number of dots (20) in both conditions. It was found that, in spite of the equal number of dots, the postural sway amplitudes were larger for the central vision conditions than for the peripheral vision conditions. In conclusion, the present study showed that peripheral rather than central vision contributes to maintaining a stable standing posture, with postural sway being influenced more in the direction of stimulus observation, or head/gaze direction, than in the direction of trunk orientation, which suggests that peripheral vision operates primarily in a viewer-centered frame of reference characterized by the head/gaze direction rather than in a body-centered frame of reference characterized by the anatomical planes of the body.  相似文献   
909.
The International Commission on Radiological Protection — whose regularly updated recommendations are routinely adopted as law throughout the globe — recently issued the first-ever ICRP protections for the environment. These draft 2005 proposals are significant both because they offer the commission’s first radiation protections for any non-human parts of the planet and because they will influence both the quality of radiation risk assessment and environmental protection, as well as the global costs of nuclear-weapons cleanup, reactor decommissioning and radioactive waste management. This piece argues that the 2005 recommendations are scientifically and ethically flawed, or gray, in at least three respects: first, in largely ignoring scientific journals while employing mainly “gray literature;” second, in relying on non-transparent dose estimates and models, rather than on actual radiation measurements; and third, in ignoring classical ethical constraints on acceptable radiation risk.  相似文献   
910.
Empowerment research has generally been limited to the individual level of analysis. Efforts to study empowerment beyond the individual require conceptual frameworks suggesting attributes that define the construct and guide its measurement. This paper presents an initial attempt to describe the nomological network of empowerment at the organizational level of analysis--organizational empowerment (OE). Intraorganizational, interorganizational, and extraorganizational components of OE are described. Implications for empowerment theory and practice are discussed.  相似文献   
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