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951.
Machado M Willardson JM Silva DR Frigulha IC Koch AJ Souza SC 《Research quarterly for exercise and sport》2012,83(2):276-281
In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4156 kg, SD = 867, for 3 min; vs. M = 3503 kg SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r = .45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets. 相似文献
952.
The paper presents a model that evaluates how upgraded technological capabilities of emerging country based multinationals (EMNCs) and an increase in the domestic market size of large emerging countries affect value chain location choices and the competitiveness of emerging country based firms versus advanced country based ones. The model shows that, even without possessing a competitive advantage in terms of technology and/or brands, EMNCs from large or rapidly technologically advancing countries can become dominant players in the global system. The model highlights the central role of firm level technological intensity and product differentiation in determining the location of value chain activities as well as defining organisational boundaries. Empirical analysis of the location choices of the world's top multinationals from large advanced and emerging countries in 2010 supports the model's predictions. 相似文献
953.
Preschool teachers and classroom aides: Same context,similar perceptions of children's behaviors? 下载免费PDF全文
This study explored the correspondence and differences between school staff perceptions of preschool children's social skills and behavior problems. One hundred preschoolers were assessed by 14 pairs of teachers and classroom aides with the Preschool and Kindergarten Behavior Scales – 2nd Edition (PKBS‐2 Portuguese version). Indexes of agreement and disagreement were calculated. Risk levels and item analyses of PKBS‐2 scores according to both informants' ratings were compared. A higher level of agreement was obtained for social skills scores than for behavior problems (mean correlation of .62). No statistically significant differences between informants were obtained for the risk levels, and item analyses revealed a similar pattern of behaviors that were most and least rated by both informants. Results indicate that the classroom aides' perspective on preschool assessment represents a reliable input, which justifies that they network with teachers in addressing preschoolers' social‐emotional and behavioral challenges. 相似文献
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956.
Andrew J. Greene Michael H. Dickson Floren Colloud Richard M. Smith 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):302-317
The effect of anthropometric differences in shank to thigh length ratio upon timing and magnitude of joint power production during the drive phase of the rowing stroke was investigated in 14 elite male rowers. Rowers were tested on the RowPerfect ergometer which was instrumented at the handle and foot stretcher to measure force generation, and a nine segment inverse dynamics model used to calculate the rower's joint and overall power production. Rowers were divided into two groups according to relative shank thigh ratio. Time to half lumbar power generation was significantly earlier in shorter shank rowers (p = 0.028) compared to longer shank rowers, who showed no lumbar power generation during the same period of the drive phase. Rowers with a relatively shorter shank demonstrated earlier lumbar power generation during the drive phase resulting from restricted rotation of the pelvic segment requiring increased lumbar extension in these rowers. Earlier lumbar power generation and extension did not appear to directly affect performance measures of the short shank group, and so can be attributed to a technical adaptation developed to maximise rowing performance. 相似文献
957.
Leonard J. Waks 《Learning Inquiry》2007,1(2):83-87
The topic of listening has been broadly neglected in educational studies. This special issue presents studies on the connections
between listening and reflecting in educational contexts.
相似文献
Leonard J. WaksEmail: |
958.
Depending on the kindness of strangers: current national data initiatives and developmental research 总被引:2,自引:0,他引:2
This article provides a brief review of current large-scale, longitudinal data collection initiatives focusing on children. These studies will be available for secondary data analyses in the twenty-first century. In addition to child outcome data, process-oriented information is being collected on child-parent interactions, quality of child care, elementary school teacher reports and classroom observations, accessibility and use of health, educational and social services, parental mental health, family violence, fathering, parental residence patterns, income and income sources, child support, employment patterns, and community characteristics. Several of these studies are randomized trials of the efficacy of early childhood intervention services and housing mobility programs. The usefulness of these efforts for exploring policy-relevant issues (child support enforcement, work requirements for welfare recipients, antipoverty strategies, housing subsidies and relocation, availability of child care, child-care subsidies) are discussed. 相似文献
959.
Friedman WJ 《Child development》2000,71(4):913-932
Four studies with 261 children were conducted to describe 4- through 10-year-olds' ability to differentiate the future distances of events. Distances ranged from later the same day through nearly a year in the future. Judgment methods included pointing to parts of a spatial scale representing future distances and answering open-ended questions. Although 4-year-olds failed to differentiate future distances, 5-year-olds were able to distinguish events that would occur in the coming weeks and months from those that would not occur for many months. However, like young children in earlier studies of memory for time, they confused the near future with the recent past. Children 6 through 8 years of age made more differentiated judgments but collapsed the distances of events more than a few months in the future. By 8 to 10 years of age, children accurately judged distances by using mental representations of the times of events in the annual cycle. 相似文献
960.
Several item bias detection methods were applied to the analysis of bias among males and females for items from a curriculum-based mathematics test. The focus of this analysis was the consistency of the methods across different test administrations of the same items. The results indicated that, of the methods studied, the Mantel–Haenszel (M–H) and IRT-based sum-of-squares methods were the most consistent. However, the degree of reliability and agreement for these methods was modest at best. As with most prior research, no reasonable explanation could be found for the most consistently flagged items. A likely reason for this lies in the confusion of visible genetic group characteristics with their instructional backgrounds. A multidimensional perspective of item bias is proposed for future research that will take such confounding into account. 相似文献