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71.
Over the years, professionals have hypothesized that a positive relationship exists between children's oral language proficiency and their written language performance. This study examined the following two aspects of the relationship between oral and written language: (a) Are specific linguistic components of language more closely related than others? (b) Do groups rated high, medium, or low on written language measures differ significantly in oral language proficiency? Measures of oral and written language were administered to 77 third-grade students. Results indicated that moderate relationships existed between grammatical aspects of oral and written language. Oral language proficiency was significantly different for groups rated high, medium, and low on the basis of written language performance.  相似文献   
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In the late 1950s, a health charity, known as the National Foundation for Infantile Paralysis (March of Dimes), organized American teens into volunteer divisions to fight polio, as well as tame adult anxieties surrounding juvenile delinquency. The alliance that developed permitted the NFIP to increase its influence and revenue, while granting teens an opportunity to assert their cultural power and challenge negative stereotypes. Although the NFIP nurtured and at times dominated the relationship, young volunteers joined for their own reasons and shaped the program to suit their own aspirations and interests.  相似文献   
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Individuals with chronic obstructive pulmonary disease (COPD) have been shown to benefit from participation in pulmonary rehabilitation (PR) programs that include exercise training and education. Purpose: To examine the relationship between improvements in 6 minute walk distance and perceived quality of life in individuals with COPD following completion of a PR program. Methods: The records of 139 individuals completing a PR program (3 times a week for 8 weeks) were retrospectively examined. Prior to entry and upon completion of the program each individual completed a 6 minute walk test (6MWT), the SF-36 Health survey, and the UCSD Shortness of Breath Questionnaire (SOB). SF-36 results were analyzed according to 8 subscales [Physical Functioning (PF), Role Physical (RF), Bodily Pain (BP), General Health (GH), Vitality (V), Social Functioning (SF), Role Emotional (RE), and Mental Health (MH)]. Results: PR resulted in significant improvements in 6MWTdistance (Pre = 845 ± 37 ft, Post = 1127 ± 32 ft, p < 0.001), PF (p < 0.001), RF (p = 0.001), Vitality (p = 0.002), SF (p < 0.001), RE (p = 0.037), MH (p < 0.001) and SOB (Pre = 53 ± 2, Post = 47 ± 2, p < 0.001). The change in 6MWT distance was not related to changes in PF (r = 0.17), RF (r = 0.03), GH (r = 0.03), Vitality (r = −0.001), SF (r = 0.01), RE (r = 0.06), MH (r = −0.04) or SOB (r = 0.12). The magnitude of improvement in 6MWT distance (68%) was much greater than that observed in PF (15%), RF (16%), GH (6%), VT (18%), SF (20%), RE (14%), MH (14%), or SOB (8%). Conclusions: PR has a positive impact on 6 minute walk distance and perceived quality of life in individuals with COPD; however, changes in 6 minute walk distance appear to have no relationship to changes in perceived quality of life.  相似文献   
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The highly unsteady flow around a rowing blade in motion is examined using a three-dimensional computational fluid dynamics (CFD) model which accounts for the interaction of the blade with the free surface of the water. The model is validated using previous experimental results for quarter-scale blades held stationary near the surface in a water flume. Steady-state drag and lift coefficients from the quarter-scale blade flume simulation are compared to those from a simulation of the more realistic case of a full-scale blade in open water. The model is then modified to accommodate blade motion by simulating the unsteady motion of the rowing shell moving through the water, and the sweep of the oar blade with respect to the shell. Qualitatively, the motion of the free surface around the blade during a stroke shows a realistic agreement with the actual deformation encountered during rowing. Drag and lift coefficients calculated for the blade during a stroke show that the transient hydrodynamic behaviour of the blade in motion differs substantially from the stationary case.  相似文献   
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In this case study, the Russell Corporation's acquisition of Spalding creates an opportunity for Spalding's marketing staff to reevaluate their licensing strategy. Prior ownership has heavily leveraged the equity of the Spalding brand to generate maximum licensing revenues with a minimal concern for the long-term impact on the brand. Placed in the position of Spalding's Vice President for Marketing, the reader must grapple with strategic licensing factors such as the rise of the big-box retailer in distribution channels and product category congruence across extensions. Ultimately, with several licensing contracts up for renewal, a decision on the future direction of the Spalding brand must be outlined and defended in a presentation to the executives at Russell.  相似文献   
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Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill.  相似文献   
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