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71.
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost.  相似文献   
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Rats were exposed twice in a rotated sequence to a series of six mazes, consisting of hexagonal alleys, balanced for different alley length and structural complexity. Locomotor activity increased with alley length and decreased with structural complexity of the mazes. Locomotion became less stereotyped with increased experience, showing an increasing number of turns, less constant velocity, loss of the initial preference for outward leading alleys and weakening of the forward tendency at reentry from side alleys into hexagonal alleys. In contrast to these qualitative changes of locomotion, the amount of activity remained almost unchanged throughout the experiment. The results suggest that these increases in locomotion complexity depend upon complex interactions between experience and stimulus content of the mazes.  相似文献   
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The purpose of this study was to determine if achievement on a series of problems was affected by differences among task values within a dimension. Values within inference pattern, goal object, and percept dimensions were studied. One hundred and sixty primary school children participated in the study. An analysis of the results of their achievement on the tasks indicate that task solution is affected by the dimension values used in this study. The results of the study suggest that a multidimensional scale of task dimension values should be constructed in order to assist the curriculum specialist in the construction and sequencing of concept tasks for specific grade levels.  相似文献   
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Adolescents (n=43) previously diagnosed as dyslexic/reading disabled had markedly lower IQ scores on the newly standardized Wechsler Intelligence Scale for Children (WISC-III) than on the earlier administered WISC-R. The declines for Verbal, Performance, and Full Scale IQs were 10, 12, and 11 points, respectively, which were twice as great as in a subset of the standardization sample given both versions of the WISC. The adolescents did not show a significant decline in standard scores from the Wide Range Achievement Test (Level I to Level II). However, only two subjects had current reading and spelling standard scores above the 25th percentile. The impact of lower WISC-III IQs on guidelines for classification of students as learning disabled is discussed.  相似文献   
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OBJECTIVE: This study had two aims: First to examine psychosocial correlates of child maltreatment risk, and second to assess the validity of the CAP Inventory (Milner, 1986) with multiply disadvantaged teenage mothers. METHOD: Participants were 75 adolescent mothers who were wards of the Illinois child protection system. Mothers (aged 14-18) and infants participated in home-based psychosocial assessment of personal and parenting functioning. Group comparisons examined differences for mothers with elevated versus normal versus invalid CAP scores due to faking good. RESULTS: Findings indicated that abuse risk groups differed on emotional distress, social support satisfaction, reading achievement, and years of education, but not on parenting beliefs or quality of child stimulation. Differences favored the normal over the elevated risk group in all significant comparisons, whereas mothers with elevated faking good differed from normals only in lower reading achievement. Multiple regression analysis highlighted emotional distress, support dissatisfaction, and low achievement as significant predictors of greater abuse risk. CONCLUSIONS: Despite sharing multiple disadvantages, adolescent wards are a heterogeneous group who show different levels of psychosocial functioning corresponding to levels of child maltreatment risk. The findings provide support for the concurrent validity and clinical applicability of the CAP Inventory with disadvantaged teenage mothers.  相似文献   
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In this article we derive the distribution, mean and variance of the number of cycles in a randomly selected permutation of the first n integers.  相似文献   
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