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121.
Utilising the oral language of a principal leading an inner-city at-risk elementary school in a large urban school district in the southwestern USA, the researchers tested behavioural integrity and the dimensions of source credibility (competence, goodwill, and trustworthiness) as antecedents to Motivating Language Theory and the ML Model. Teacher perception data at the Title I elementary school was used for this quantitative study. Over 95% of the teachers responded to a survey each year for a three-year period. Each year, there were statistically significant correlations between each of the antecedents and motivating language. The antecedents accounted for 66–75% of the total variance for motivating language depending on the year based on regression analysis. The results of this study extend the field of Motivating Language Theory and the ML Model, and further explain how the work of principals is accomplished.  相似文献   
122.
This study addresses measurement issues around a standards-based content analysis of mathematics textbooks’ coverage of standards for use in large-scale monitoring of standards implementation as proposed in a 2013 report by the National Research Council. An earlier study produced an exhaustive content analysis of textbooks using the 2012 Common Core State Standards for Mathematics. This yielded an accurate and reliable portrait of a textbook's coverage of standards. However, such an in-depth analysis is not feasible for large-scale standards-implementation monitoring in which a large number of textbooks may need to be analyzed. To provide such a portrait with sufficient accuracy while also substantially reducing the associated resources needed to produce such a portrait, a simulation study was conducted with the exhaustively coded database to compare different sampling schemes. Results indicated that sampling 1 day from each week and coding the corresponding lessons led to sufficiently accurate representations of the overall content of the textbook. The results provide empirical evidence for large-scale standards-based content analyses of mathematics textbooks for monitoring standards implementation which could be adapted for other subject areas.  相似文献   
123.
ABSTRACT

Purpose: Most built environment studies have quantified characteristics of the areas around participants’ homes. However, the environmental exposures for physical activity (PA) are spatially dynamic rather than static. Thus, merged accelerometer and global positioning system (GPS) data were utilized to estimate associations between the built environment and PA among adults. Methods: Participants (N = 142) were recruited on trails in Massachusetts and wore an accelerometer and GPS unit for 1–4 days. Two binary outcomes were created: moderate-to-vigorous PA (MVPA vs. light PA-to-sedentary); and light-to-vigorous PA (LVPA vs. sedentary). Five built environment variables were created within 50-meter buffers around GPS points: population density, street density, land use mix (LUM), greenness, and walkability index. Generalized linear mixed models were fit to examine associations between environmental variables and both outcomes, adjusting for demographic covariates. Results: Overall, in the fully adjusted models, greenness was positively associated with MVPA and LVPA (odds ratios [ORs] = 1.15, 95% confidence interval [CI] = 1.03, 1.30 and 1.25, 95% CI = 1.12, 1.41, respectively). In contrast, street density and LUM were negatively associated with MVPA (ORs = 0.69, 95% CI = 0.67, 0.71 and 0.87, 95% CI = 0.78, 0.97, respectively) and LVPA (ORs = 0.79, 95% CI = 0.77, 0.81 and 0.81, 95% CI = 0.74, 0.90, respectively). Negative associations of population density and walkability with both outcomes reached statistical significance, yet the effect sizes were small. Conclusions: Concurrent monitoring of activity with accelerometers and GPS units allowed us to investigate relationships between objectively measured built environment around GPS points and minute-by-minute PA. Negative relationships between street density and LUM and PA contrast evidence from most built environment studies in adults. However, direct comparisons should be made with caution since most previous studies have focused on spatially fixed buffers around home locations, rather than the precise locations where PA occurs.  相似文献   
124.
125.
Abstract

This study was concerned with the effect of bench-stepping in the Harvard Step Test upon finger and foot reaction time and, secondarily, with ascertaining the relationship, if any, between these reaction times and scores on the Harvard Step Test. The subjects were university freshman males. Reaction times were taken before, immediately after, and four minutes after the stepping exercise for 80 subjects. Thirty-six subjects served as controls, involving the reaction times and pulse counts at the prescribed intervals but without exercise. The findings failed to divulge any discernible effect of stepping exercise upon reaction time, or any apparent relationship between reaction time and the sum of the recovery pulse counts following the exercise. In view of these findings it is suggested that study be directed to two related aspects — the effect of exercise to exhaustion on reaction time, and the effect of strenuous and exhaustive exercise upon speed of movement.  相似文献   
126.
127.
Gymnastics vaulting relies on a specialized take‐off board for propulsion during the take‐off phase of the vault. There is little information on the vault board and its behaviour. The aim of this study was to characterize the behaviour of the vault board during handspring drill take‐offs of young male gymnasts (n = 36). The side of the top surface of the vault board and the wooden base were marked with three reflective markers, placed at the end of the vault board nearest the vault table and the centres of the two rearmost coil springs. The vault board surface was divided into two areas, rear and middle, based on marker location. The gymnasts’ groups were determined from the location of the gymnast's lateral malleolus at vault board contact. Landings with the malleolus directly above or behind the rearmost marker were considered rear landings; landings with the malleolus forward of the rearmost marker were considered middle landings. Marker movements were automatically digitized and the right malleolus was hand digitized at 120 Hz. The maximum vertical displacement, vertical deflection time, and vertical velocity at take‐off of the vault board markers did not differ statistically between board contact groups (all p > 0.05). The lateral malleolus velocity components also did not differ between board contact groups. Some low to moderately strong correlations were observed between the various marker displacements, durations and take‐off velocities. Modest correlations were obtained between board markers and right malleolus velocities. The results indicate that foot contact on the vault board, as defined here, did not result in differences in board marker behaviour or right lateral malleolus velocities. This information does not support the idea that vault board contacts at the rear of the vault board are worse than contacts near the middle of the vault board. More research is needed to ascertain the role of the vault board's vibration characteristics to whole body actions that are observed in the subsequent preflight phase.  相似文献   
128.
Abstract

An A-B-A-B time-series design was used to determine the effectiveness of a group contingency strategy in modifying on-task behavior of behaviorally disordered students in a physical education setting. A younger group (n = 12) with a mean age of 7.8 years, and an older group (n = 11) with a mean age of 11.2 years, participated in a study in which activity reinforcement for each group was contingent upon correct observation of the rules established for class. The group contingency strategy was significantly effective in increasing the percentage of on-task behavior of both groups of students. In addition, there was no significant difference in the response to treatment between younger and older students, and there were no individuals within either group who did not respond favorably to treatment.  相似文献   
129.
The purpose of the study was to compare young sprint and distance runners for changes in their cardiac dimensions with increased age (10–17 years) or body surface area (1–2 m2). Echocardiographic dimensions were obtained on 73 male track athletes competing in the 1983 National Age Group Track and Field Association championships. Each group of athletes was also compared with a hypothetical normal population (matched for weight and age) generated from prediction equations derived by Henry, Gardin, & Ware (1980). The cardiac dimensions examined were: Left ventricular internal diameter, left ventricular posterior wall thickness, and interventricular septum thickness. The male distance runners (n = 38) had a significantly greater increase in left ventricular posterior wall thickness and interventricular septum thickness with increasing age or increasing body surface area compared to the sprinters (n = 35) or compared to the predicted normal population. The left ventricular internal diameter was not significantly different between the groups. These results indicate that the hearts of male distance runners are undergoing a training hypertrophy whereas the hearts of sprinters are no different than hearts in a normal population. The changes in cardiac dimensions of these young athletes run counter to the generalizations stated for adult athletes: That endurance training enlarges the left ventricular internal diameter, but does not increase the left ventricular posterior wall or interventricular septum thickness.  相似文献   
130.
Much is written at the elementary school level concerning bullying and the socioemotional needs of gifted and talented (GT) students; however, in the last 10 years, little qualitative research exists concerning the early adolescent GT age group. In the social environment of classroom life, early and current research indicates that many of these students experience neurotic perfectionism, overexciteabilities (OEs), developmental asynchrony, and bullying. The formation of autonomous classes (GT-only classes) has afforded some hope concerning the amelioration of such problems; nevertheless, in this study, detailed evidence of classroom bullying in the form of social ostracism and teasing has been found with this GT age group. If left unchecked, psychological autopsies have shown these students suffering emotional difficulties and even committing suicide as a result of school and classroom torment. With such potential for classroom bullying problems, few studies address what veteran teachers of early adolescent GT students do to keep students psychologically safe. Within the social milieu of classroom life, and in comparison to research standards, this study explores three efficacious teacher perspectives and practices.  相似文献   
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