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251.
OBJECTIVE: To determine whether child maltreatment is associated with obesity in preschool children. METHODS: Data were obtained from the Fragile Families and Child Wellbeing Study, a birth cohort study of 4898 children born between 1998 and 2000 in 20 large US cities. At 3 years of age, 2412 of these children had their height and weight measured, and mothers answered items on the Parent-Child Conflict Tactics Scales about three types of child maltreatment--neglect, corporal punishment, and psychological aggression. The frequency of each type of maltreatment behavior in the prior year was analyzed using categories--ever/never for neglect and quintiles for the other two types of maltreatment. Child obesity was defined as measured body mass index (kg/m(2)) > or =95th percentile. RESULTS: Eighteen percent of the children were obese, and the prevalence of any episode of neglect, corporal punishment, and psychological aggression was 11%, 84%, and 93%, respectively. The odds of obesity were increased in children who had experienced neglect (odds ratio 1.56, 95% confidence interval, 1.14-2.14), after controlling for the income and number of children in the household, the mothers' race/ethnicity, education, marital status, body mass index, prenatal smoking, and age, and the children's sex and birth weight. Neither the frequency of corporal punishment nor psychological aggression was associated with an increased risk of obesity. CONCLUSIONS: In a sample of preschool children from 20 large US cities, maternal self-report of neglectful behavior was associated with an increased risk of childhood obesity, after controlling for birth weight, maternal obesity, and multiple socioeconomic factors. 相似文献
252.
Development of gender attitude traditionality across middle childhood and adolescence 总被引:2,自引:2,他引:0
The development of gender attitudes in 402 youth (201 firstborn and 201 secondborn siblings) in 201 European American families was examined using data collected on seven occasions across 9 years. Pooling across siblings and using multilevel modeling, we examined gender attitude development from ages 7 to 19. Consistent with an ecological perspective, the combined effects of individual (i.e., sex, age, birth order) and contextual (i.e., parents' gender attitudes, sibling sex) characteristics predicted patterns of change. Although most youth declined in traditionality, the attitudes of firstborn boys with brothers and traditional parents became more traditional over time. No one longitudinal pattern captured the development of gender attitudes; trajectories varied as a function of contextual and personal characteristics. 相似文献
253.
在今后十年内,美国必须依赖航天飞机和现有的一次使用发射工具进入太空。在研制下一世纪使用的发射工具之前,必须首先确定空间计划的目标。 相似文献
254.
今年第一次天气预报提醒人们由于寒潮将至,每一个家庭应注意防护最容易受到损坏的水管。人们知道防止水管中的水冷凝可以避免水由液态转变为固态的过程中膨胀造成的破坏。但是许多人并不知道他们同时也防止了因为冰的表面仍保持液态而产生的一种更大的压力。 相似文献
256.
Economic evaluation research in the context of Child Welfare policy: a structured literature review and recommendations 总被引:1,自引:0,他引:1
Goldhaber-Fiebert JD Snowden LR Wulczyn F Landsverk J Horwitz SM 《Child abuse & neglect》2011,35(9):722-740
Objectives
With over 1 million children served by the US Child Welfare system at a cost of $20 billion annually, this study examines the economic evaluation literature on interventions to improve outcomes for children at risk for and currently involved with the system, identifies areas where additional research is needed, and discusses the use of decision-analytic modeling to advance Child Welfare policy and practice.Methods
The review included 19 repositories of peer-reviewed and non-peer-reviewed “gray” literatures, including items in English published before November, 2009. Original research articles were included if they evaluated interventions based on costs and outcomes. Review articles were included to assess the relevance of these techniques over time and to highlight the increasing discussion of methods needed to undertake such research. Items were categorized by their focus on: interventions for the US Child Welfare system; primary prevention of entry into the system; and use of models to make long-term projections of costs and outcomes.Results
Searches identified 2,640 articles, with 49 ultimately included (19 reviews and 30 original research articles). Between 1988 and 2009, reviews consistently advocated economic evaluation and increasingly provided methodological guidance. 21 of the original research articles focused on Child Welfare, while 9 focused on child mental health. Of the 21 Child Welfare articles, 81% (17) focused on the US system. 47% (8/17) focused exclusively on primary prevention, though 83% of the US system, peer-reviewed articles focused exclusively on prevention (5/6). 9 of the 17 articles included empirical follow-up (mean sample size: 264 individuals; mean follow-up: 3.8 years). 10 of the 17 articles used modeling to project longer-term outcomes, but 80% of the articles using modeling were not peer-reviewed. Although 60% of modeling studies included interventions for children in the system, all peer-reviewed modeling articles focused on prevention.Conclusions
Methodological guidance for economic evaluations in Child Welfare is increasingly available. Such analyses are feasible given the availability of nationally representative data on children involved with Child Welfare and evidence-based interventions.Practice implications
Policy analyses considering the long-term costs and effects of interventions to improve Child Welfare outcomes are scarce, feasible, and urgently needed. 相似文献257.
The effectiveness of phonological instruction with 6 deaf students in an oral program was investigated. In a previous investigation (Syverud, Guardino, & Selznick, 2009), promising results had been obtained in a case study in which the Direct Instruction curriculum titled Teach Your Child to Read in 100 Easy Lessons (Engelmann, Haddox, & Bruner, 1983) was used with an oral-deaf child. Given these results, Syverud and Guardino were asked to replicate the procedures with additional struggling readers. A multiple case study design was implemented for a period of 10 weeks. Tests of nonsense words were administered to monitor weekly progress in phonological decoding. Intervention journals were completed for each tutoring session to provide qualitative information. Although the results were mixed, all 6 participants showed gains in phonological decoding skills. Suggestions for both practitioners and researchers are offered. 相似文献
258.
In this study, we examined thermoregulatory responses to ingestion of separate aliquots of drinks at different temperatures during low-intensity exercise in conditions of moderate heat stress. Eight men cycled at 50% (s = 3) of their peak oxygen uptake (VO2peak) for 90 min (dry bulb temperature: 25.3 degrees C, s = 0.5; relative humidity: 60%, s = 5). Four 400-ml aliquots of flavoured water at 10 degrees C (cold), 37 degrees C (warm) or 50 degrees C (hot) were ingested after 30, 45, 60, and 75 min of exercise. Immediately after the 90 min of exercise, participants cycled at 95% VO2peak to exhaustion to assess exercise capacity. There were no differences between trials in rectal temperature at the end of the 90 min of exercise (cold: 38.11 degrees C, s = 0.30; warm: 38.10 degrees C, s = 0.33; hot: 38.21 degrees C, s = 0.30; P = 0.765). Mean skin temperature between 30 and 90 min tended to be influenced by drink temperature (cold: 34.49 degrees C, s = 0.64; warm: 34.53 degrees C, s = 0.69; hot: 34.71 degrees C, s = 0.48; P = 0.091). Mean heart rate from 30 to 90 min was higher in the hot trial (129 beats . min(-1), s = 7; P < 0.05) than on the cold (124 beats . min(-1), s = 9) and warm trials (126 beats . min(-1), s = 8). Ratings of thermal sensation were higher on the hot trial than on the cold trial at 35 and 50 min (P < 0.05). Exercise capacity was similar between trials (P = 0.963). The heat load and debt induced by periodic drinking resulted in similar body temperatures during low-intensity exercise in conditions of moderate heat stress due to appropriate thermoregulatory reflexes. 相似文献
259.
Rampinini E Impellizzeri FM Castagna C Abt G Chamari K Sassi A Marcora SM 《Journal of sports sciences》2007,25(6):659-666
The aim of this study was to examine the effects of exercise type, field dimensions, and coach encouragement on the intensity and reproducibility of small-sided games. Data were collected on 20 amateur soccer players (body mass 73.1 +/- 8.6 kg, stature 1.79 +/- 0.05 m, age 24.5 +/- 4.1 years, VO(2max) 56.3 +/- 4.8 ml x kg(-1) x min(-1)). Aerobic interval training was performed during three-, four-, five- and six-a-side games on three differently sized pitches, with and without coach encouragement. Heart rate, rating of perceived exertion (RPE) on the CR10-scale, and blood lactate concentration were measured. Main effects were found for exercise type, field dimensions, and coach encouragement (P < 0.05), but there were no interactions between any of the variables (P > 0.15). During a six-a-side game on a small pitch without coach encouragement, exercise intensity was 84 +/- 5% of maximal heart rate, blood lactate concentration was 3.4 +/- 1.0 mmol x l(-1), and the RPE was 4.8. During a three-a-side game on a larger pitch with coach encouragement, exercise intensity was 91 +/- 2% of maximal heart rate, blood lactate concentration was 6.5 +/- 1.5 mmol x l(-1), and the RPE was 7.2. Typical error expressed as a coefficient of variation ranged from 2.0 to 5.4% for percent maximal heart rate, from 10.4 to 43.7% for blood lactate concentration, and from 5.5 to 31.9% for RPE. The results demonstrate that exercise intensity during small-sided soccer games can be manipulated by varying the exercise type, the field dimensions, and whether there is any coach encouragement. By using different combinations of these factors, coaches can modulate exercise intensity within the high-intensity zone and control the aerobic training stimulus. 相似文献
260.
Nine males cycled at 53% (s = 2) of their peak oxygen uptake (VO(2peak)) for 90 min (dry bulb temperature: 25.4 degrees C, s = 0.2; relative humidity: 61%, s = 3). One litre of flavoured water at 10 (cold), 37 (warm) or 50 degrees C (hot) was ingested 30 - 40 min into exercise. Immediately after the 90 min of exercise, participants cycled at 95%VO(2peak) to exhaustion to assess exercise capacity. Rectal and mean skin temperatures and heart rate were recorded. The gradient of rise in rectal temperature was influenced (P < 0.01) by drink temperature. Mean skin temperature was highest in the hot trial (cold trial: 34.2 degrees C, s = 0.5; warm trial: 34.4 degrees C, s = 0.5; hot trial: 34.7 degrees C, s = 0.6; P < 0.01). Significant differences were observed in heart rate (cold trial: 132 beats . min(-1), s = 13; warm trial: 134 beats . min(-1), s = 12; hot trial: 139 beats . min(-1), s = 13; P < 0.05). Exercise capacity was similar between trials (cold trial: 234 s, s = 69; warm trial: 214 s, s = 52; hot trial: 203 s, s = 53; P = 0.562). The heat load and debt induced via drinking resulted in appropriate thermoregulatory reflexes during exercise leading to an observed heat content difference of only 33 kJ instead of the predicted 167 kJ between the cold and hot trials. These results suggest that there may be a role for drink temperature in influencing thermoregulation during exercise. 相似文献