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11.
This study aimed to (1) profile a professional boxer (23 years and 80 kg) with boxing-specific, muscle function, aerobic capacity and body composition tests, and (2) quantify how these measures varied during an 8-week preparation phase leading to, and post a state-Title Bout fought in the 76.2-kg class. A series of boxing-specific and muscle function tests were completed on 11 occasions: 9 prior and twice after the bout, each separated by approximately 2 weeks. The boxing test included 36 maximal punches (9 of each: lead and rear straights, lead and rear hooks) to a punching integrator measuring forces and velocity. Muscle function tests included countermovement jump, drop-jumps, isometric mid-thigh pull and isometric bench-press. Body composition was assessed using skin-fold measurements on three occasions and one dual energy X-ray absorptiometry scan. Aerobic capacity was assessed using 2 VO2 max tests. Leading up to the bout, performance decreased in isometric mid-thigh pull (8%), isometric bench-press (5%), countermovement jump (15%) and impact forces in 3 of 4 punches (4%–7%). Whereas measures of dynamic and isometric muscle function remained depressed or unchanged post competition, punching forces (6%–15%) and aerobic power (6%) increased. Data suggest the athlete may have super-compensated following rest as fatigue dissipated and further adaptation occurred. 相似文献
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Five suburban community colleges in a metropolitan area collaborated on a survey to parents of high school graduates of the class of 2002 who attended the colleges in fall 2002. The study was undertaken to learn more about parents roles in their students selection of community colleges, to give insights and information about this important community college constituency, and to assist community colleges to shape more effective ways to foster positive and supportive opinions among parents of potential students. Parents want the community college to provide students with credits and grade point averages enabling transfer, overestimate their students academic skills as measured by course placement tests, engaged in a number of college-choice activities, and indicate that factors associated with lifestyle and money were major reasons for selecting the community college. Associations between parents social capital and perceptions of their students academic abilities were found for a number of dependent variables examined. The study also revealed important differences in how participating institutions record and calculate key measures such as credits earned and grade point averages. 相似文献
14.
We investigated differences between field-study classrooms and traditional science classrooms in terms of the learning environment and students’ attitudes to science, as well as the differential effectiveness of field-study classrooms for students differing in sex and English proficiency. A modified version of selected scales from the What Is Happening In this Class? questionnaire was used to assess the learning environment, whereas students’ attitudes were assessed with a shortened version of a scale from the Test of Science Related Attitudes. A sample of 765 grade 5 students from 17 schools responded to the learning environment and attitude scales in terms of both their traditional science classrooms and classrooms at a field-study centre in Florida. Large effect sizes supported the effectiveness of the field-studies classroom in terms of both the learning environment and student attitudes. Relative to the home school science class, the field-study class was considerably more effective for students with limited English proficiency than for native English speakers. 相似文献
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16.
Loneliness and Peer Relations in Young Children 总被引:13,自引:0,他引:13
Recent studies indicate that feelings of loneliness and social dissatisfaction can be reliably assessed with third- through sixth-grade children, and that children who are sociometrically rejected by their peers are significantly more lonely than other children. The present research was designed (a) to examine whether loneliness could be reliably assessed in a population younger than previously studied, (b) to learn whether young children who are poorly accepted by peers report elevated levels of loneliness and social dissatisfaction, (c) to assess whether young children understand the concept of loneliness, and (d) to examine the behavioral characteristics of lonely young children. Kindergarten and first-grade children (N = 440) responded to a questionnaire about feelings of loneliness and social dissatisfaction in school. A subset of children (N = 46) were individually interviewed to assess their understanding of loneliness. To assess sociometric status and behavior, peers were asked to respond to various sociometric measures and behavioral assessment items. Teachers also provided behavioral information about children using a newly developed instrument. Results indicated that nearly all children understood loneliness, that loneliness was reliably assessed in young children, and that poorly accepted children were more lonely than other children. In addition, children who reported the most loneliness were found to differ from others on several behavioral dimensions. 相似文献
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18.
This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow
through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction
by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional.
The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature
field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs. 相似文献
19.
This meta-analysis integrates 296 effect sizes reported in eye-tracking research on expertise differences in the comprehension
of visualizations. Three theories were evaluated: Ericsson and Kintsch’s (Psychol Rev 102:211–245, 1995) theory of long-term working memory, Haider and Frensch’s (J Exp Psychol Learn Mem Cognit 25:172–190, 1999) information-reduction hypothesis, and the holistic model of image perception of Kundel et al. (Radiology 242:396–402, 2007). Eye movement and performance data were cumulated from 819 experts, 187 intermediates, and 893 novices. In support of the
evaluated theories, experts, when compared with non-experts, had shorter fixation durations, more fixations on task-relevant
areas, and fewer fixations on task-redundant areas; experts also had longer saccades and shorter times to first fixate relevant
information, owing to superiority in parafoveal processing and selective attention allocation. Eye movements, reaction time,
and performance accuracy were moderated by characteristics of visualization (dynamics, realism, dimensionality, modality,
and text annotation), task (complexity, time-on-task, and task control), and domain (sports, medicine, transportation, other).
These findings are discussed in terms of their implications for theories of visual expertise in professional domains and their
significance for the design of learning environments. 相似文献
20.
Learners studying mechanical or technical processes via dynamic visualizations often fail to build an accurate mental representation
of the system’s movements. Based on embodied theories of cognition assuming that action, perception, and cognition are closely
intertwined, this paper proposes that the learning effectiveness of dynamic visualizations could be enhanced by grounding
the movements of the presentation in people’s own bodily experiences during learning. We discuss recent research on embodied
cognition and provide specific strategies for how the body can be used to ground movements during the learning process: (1)
making or observing gestures, (2) manipulating and interacting with objects, (3) using body metaphors, and (4) using eye movements
as retrieval cues. Implications for the design of dynamic visualizations as well as directions for future research are presented. 相似文献