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51.
In baseball and softball, there is a rule that allows the home team to have the last at-bat and thus the final opportunity to win the game. However, in tournament play, this rule is often set aside and, instead, batting order is decided by other means (e.g. tournament rules, the flip of a coin). The purpose of this study was to examine the impact of the batting last rule on game outcome in NCAA men's regional tournament baseball. It was hypothesized that host (i.e. home) teams would win a greater percentage of the games in which they batted last compared with when they batted first. This hypothesis was not supported. Closer examination of the last inning of play showed home teams were no more likely to have won the game during their last bat than visitors playing other visitors. The results suggest that the batting last rule contributes minimally, if at all, to home advantage in NCAA tournament baseball.  相似文献   
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Carbohydrate ingestion before and during endurance exercise delays the onset of fatigue (reduced power output). Therefore, endurance athletes are recommended to ingest diets high in carbohydrate (70% of total energy) during competition and training. However, increasing the availability of plasma free fatty acids has been shown to slow the rate of muscle and liver glycogen depletion by promoting the utilization of fat. Ingested fat, in the form of long-chain (C 16-22 ) triacylglycerols, is largely unavailable during acute exercise, but medium-chain (C 8-10 ) triacylglycerols are rapidly absorbed and oxidized. We have shown that the ingestion of medium-chain triacylglycerols in combination with carbohydrate spares muscle carbohydrate stores during 2 h of submaximal (< 70% VO 2 peak) cycling exercise, and improves 40 km time-trial performance. These data suggest that by combining carbohydrate and medium-chain triacylglycerols as a pre-exercise supplement and as a nutritional supplement during exercise, fat oxidation will be enhanced, and endogenous carbohydrate will be spared. We have also examined the chronic metabolic adaptations and effects on substrate utilization and endurance performance when athletes ingest a diet that is high in fat (> 70% by energy). Dietary fat adaptation for a period of at least 2-4 weeks has resulted in a nearly two-fold increase in resistance to fatigue during prolonged, low- to moderate-intensity cycling (< 70% VO 2 peak). Moreover, preliminary studies suggest that mean cycling 20 km time-trial performance following prolonged submaximal exercise is enhanced by 80 s after dietary fat adaptation and 3 days of carbohydrate loading. Thus the relative contribution of fuel substrate to prolonged endurance activity may be modified by training, pre-exercise feeding, habitual diet, or by artificially altering the hormonal milieu or the availability of circulating fuels. The time course and dose-response of these effects on maximizing the oxidative contribution of fat for exercise metabolism and in exercise performance have not been systematically studied during moderate- to high-intensity exercise in humans.  相似文献   
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One hundred and three children attending Learning Assistance Centres due to reading difficulties and one hundred and three matched, average readers were administered a battery of auditory perceptual processing tasks. The battery was composed of auditory analysis and synthesis, auditory sequential memory, auditory discrimination, and phonemic segmentation tasks. A principal components analysis yielded four factors. These were determined to be advanced phonological awareness, sequential memory, discrimination, and simple phonological awareness. Discriminant analyses, using the factor scores, indicated that three of the four factors were able to discriminate between the able and disabled readers. Most notable among these was advanced phonological awareness. Auditory discrimination could not discriminate between the groups. The results suggest that there may not be one underlying phonological ability implicated in successful reading acquisition. Furthermore, it is clear that two levels of phonological awareness exist and that screening and diagnostic instruments should address both in order to have predictive validity.  相似文献   
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Pedagogy Against the State   总被引:1,自引:0,他引:1  
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The study was designed to investigate the influence of student characteristics and classroom characteristics on students' inquiry skill. The sample consisted of a national stratified random sample of 1955 17-year-olds who were assessed as part of the 1981-1982 national assessment in science. The dependent variable was a 17-item measure of students' inquiry skill. The independent variables were selected from the available data using the Model of Educational Productivity as a guide in the selection of the variables. The first purpose of the study was to test the effectiveness of the Model of Educational Productivity for predicting the inquiry skill of 17-year-olds. The results of this study indicate that this model was capable of accounting for between 24 and 32% of the variance in inquiry skill for the general population of 17-year-olds. More specifically, students' reporting of their general ability alone accounted for between 17 and 22% of the variance. The second question posed by this study asked whether the prediction of inquiry skill differed for males and females. While there was some difference in the contribution of the minor predictors, there was very little difference in the prediction of inquiry skill for males and females using the Model of Education Productivity. The third question posed by this study asked whether the prediction of inquiry skill differed for white and nonwhite students. For nonwhite students, the Model of Educational Productivity accounted for only 18% of the variance in science inquiry skill. Thus, it would appear that there is a great deal that is not known about the factors that contribute to the science inquiry skill of nonwhite students.  相似文献   
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This paper describes a study of observed relationships between the design of a preservice elementary mathematics methods course with accompanying field practicum and changes in the extent to which participating prospective teachers identified themselves with the mathematics reform movement after becoming practicing teachers. The curriculum of the course with its embedded field practicum experiences was designed to support prospective teachers in interweaving methods coursework and pedagogical instruction with classroom practice. University and elementary school structures were interwoven by conducting weekly mathematics methods course sessions at a school site followed immediately by related practicum experiences in classrooms in the school. The interweaving of conceptualizations about mathematics teaching and learning was facilitated as the methods instructor provided professional development for classroom teachers simultaneously with the methods course, encouraging the teachers to create “reform-friendly” classroom environments. Survey data from 68 prospective teachers involved in the project were analyzed to identify and describe relationships between course/practicum experiences and the degree to which they as practicing teachers, 1–3 years following the course/practicum, identified with a reform mathematics perspective, as well as to examine factors influencing those relationships.  相似文献   
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