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991.
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A parent aide program using volunteer experienced mothers to prevent reabuse of children (tertiary prevention) has been highly successful (97% prevention) in Southern Adelaide, South Australia. The program was modeled on that described by Kempe and widely used in North America. Only minor modifications have been required to establish the program in South Australia. The outcome of the first five years' experience indicates that, despite a work load of more than 20 hours per month per client, less than 10% of volunteer parent aides withdrew from their two-year commitment to the program. The cost-benefit ratio of the program appears very low and the prevention of reabuse by mothers involved was less than that for other clients assessed by the Southern Metropolitan Child Protection Panel, which referred all cases for a parent aide in the five-year period reviewed. Difficulties in maintaining the program did arise but were dealt with by close liaison between the parent aide, the program coordinators, and the primary care worker in the community who was usually a social worker in the Department for Community Welfare. The parent aide program has proved a cost-effective and successful method of tertiary prevention.  相似文献   
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The purposes of this study were to: (a) examine the differences within 11 specific kinematic variables and an outcome measure (ball velocity) associated with component developmental levels of humerus and forearm action (Roberton & Halverson, 1984), and (b) if the differences in kinematic variables were significantly associated with the differences in component levels, determine potential kinematic constraints associated with skilled throwing acquisition. Significant differences among component levels in five of six humerus kinematic variables (p <.01) and all five forearm kinematic variables (p < .01) were identified using multivariate analysis of variance. These kinematic variables represent potential control parameters and, therefore, constraints on overarm throwing acquisition.  相似文献   
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The aim of this study was to examine the effects of active versus passive recovery on blood lactate disappearance and subsequent maximal performance in competitive swimmers. Fourteen male swimmers from the University of Virginia swim team (mean age 20.3 years, s= 4.1; stature 1.85 m, s= 2.2; body mass 81.1 kg, s= 5.6) completed a lactate profiling session during which the speed at the lactate threshold (V(LT)), the speed at 50% of the lactate threshold (V(LT.5)), and the speed at 150% of the lactate threshold (V(LT1.5)) were determined. Participants also completed four randomly assigned experimental sessions that consisted of a 200-yard maximal-effort swim followed by 10 min of recovery (passive, V(LT.5), V(LT), V(LT1.5)) and a subsequent 200-yard maximal effort swim. All active recovery sessions resulted in greater lactate disappearance than passive recovery (P < 0.0001 for all comparisons), with the greatest lactate disappearance associated with recovery at V(LT) (P= 0.006 and 0.007 vs. V(LT.5) and V(LT1.5) respectively) [blood lactate disappearance was 2.1 mmol l(-1) (s= 2.0), 6.0 mmol l(-1) (s=2.6), 8.5 mmol l(-1) (s= 1.8), and 6.1 mmol l(-1) (s= 2.5) for passive, V(LT.5), V(LT), and V(LT1.5) respectively]. Active recovery at VLT and V(LT1.5) resulted in faster performance on time trial 2 than passive recovery (P=0.005 and 0.03 respectively); however, only active recovery at V(LT) resulted in improved performance on time trial 2 (TT2) relative to time trial 1 (TT1) [TT2- TT1: passive +1.32 s (s= 0.64), V(LT.5) +1.01 s (s= 0.53), V(LT) -1.67 s (s= 0.26), V(LT1.5) -0.07 s (s = 0.51); P < 0.0001 for V(LT)). In conclusion, active recovery at the speed associated with the lactate threshold resulted in the greatest lactate disappearance and in improved subsequent performance in all 14 swimmers. Our results suggest that coaches should consider incorporating recovery at the speed at the lactate threshold during competition and perhaps during hard training sessions.  相似文献   
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Home-based reinforcement techniques have been used successfully to decrease a number of disruptive classroom behaviors. Few studies have been conducted, however, examining the effects of home-based reinforcement as a tool to increase positive school performance. This study examined the effects of a daily report card procedure designed to increase the completion and accuracy of in-class assignments in two youngsters described as having a behavioral history of difficulty in completing seat work, a problem commonly encountered in elementary school classes. The use of the procedure produced immediate significant changes in rates of both completion and accuracy for the two participants in the study. Results and problems of using the home-based reinforcement procedure are discussed.  相似文献   
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ABSTRACT

Heart rate (HR), when combined with accelerometry, can dramatically improve estimates of energy expenditure and sleep. Advancements in technology, via the development and introduction of small, low-cost photoplethysmography devices embedded within wrist-worn consumer wearables, have made the collection of heart rate (HR) under free-living conditions more feasible. This systematic review and meta-analysis compared the validity of wrist-worn HR estimates to a criterion measure of HR (electrocardiography ECG or chest strap). Searches of PubMed/Medline, Web of Science, EBSCOhost, PsycINFO, and EMBASE resulted in a total of 44 articles representing 738 effect sizes across 15 different brands. Multi-level random effects meta-analyses resulted in a small mean difference (beats per min, bpm) of ?0.40 bpm (95 confidence interval (CI) ?1.64 to 0.83) during sleep, ?0.01 bpm (?0.02 to 0.00) during rest, ?0.51 bpm (?1.60 to 0.58) during treadmill activities (walking to running), while the mean difference was larger during resistance training (?7.26 bpm, ?10.46 to ?4.07) and cycling (?4.55 bpm, ?7.24 to ?1.87). Mean difference increased by 3 bpm (2.5 to 3.5) per 10 bpm increase of HR for resistance training. Wrist-worn devices that measure HR demonstrate acceptable validity compared to a criterion measure of HR for most common activities.  相似文献   
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