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41.
Project GRAD (Graduate Ready for Activity Daily) evaluates a university course to promote physical activity. In a randomized study, 338 university seniors participated in either an intervention or control course for academic credit, and posttest data were collected on 321. The control course was knowledge-oriented. The intervention course taught behavior change skills in weekly lectures and peer-led labs. Physical activity was assessed with 7-Day Physical Activity Recall interviews. The intervention had no significant effects on men. Among women, the intervention increased total physical activity during leisure, strengthening exercises, and flexibility exercise. This university course had the intended effects of promoting healthful patterns of physical activity among women, but no effects were observed on men, who were more active than women at baseline.  相似文献   
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The kinematic analysis of competition breaststroke swimming has tended to focus on the mean values of swimming speed, stroke rate and stroke length; values in individual lengths, as well as the start, turns and finish, have largely been ignored. This study includes all such variables and aims to improve the coach's holistic understanding of breaststroke racing by determining the relationships and differences between and within these selected kinematic variables. We also compare 100-m events with 200-m events to determine if there are characteristic differences between them. Competitive breaststroke swimming performances in 100-m events (males: n = 159, finishing time = 65.05 +/- 2.62 s; females: n = 158, finishing time = 74.04 +/- 3.66 s) and 200-m events (males: n = 159, finishing time = 141.47 +/- 6.15 s; females: n = 158, finishing time = 158.66 +/- 7.87 s) were collected and analysed from 12 world, international and national championships. The better 100-m and 200-m breaststroke swimmers were found to demonstrate greater competency in the kinematic variables measured, except stroke kinematics, which were unique to each individual. These findings suggest that coaches should place emphasis on all of the kinematic components in training and that they should attempt to identify the stroke rate to stroke length ratio most appropriate for the individual. Finally, characteristic differences do exist between the 100-m and 200-m events, which has implications for how swimmers might train for each event.  相似文献   
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The University of Oklahoma Health Sciences Center (OUHSC) Library mailed a MEDLINE End User Practice Survey Form to 310 health professionals who had attended MEDLINE seminars supported by a two-year NLM grant. The survey sought to determine how many respondents had obtained NLM codes, reasons for not obtaining a code, searching time done since the seminar, differences in the use of information since taking the seminar, factors helpful in successful searching, and factors contributing to frustrations. The most prevalent reasons for not obtaining a code were lack of a microcomputer and modem, infrequent use of MEDLINE, cost, lack of time, complications, and ability to obtain free searches.  相似文献   
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Abstract

A key element contributing to deteriorating exercise capacity during physically demanding sport appears to be reduced carbohydrate availability coupled with an inability to effectively utilize alternative lipid fuel sources. Paradoxically, cognitive and physical decline associated with glycogen depletion occurs in the presence of an over-abundance of fuel stored as body fat that the athlete is apparently unable to access effectively. Current fuelling tactics that emphasize high-carbohydrate intakes before and during exercise inhibit fat utilization. The most efficient approach to accelerate the body’s ability to oxidize fat is to lower dietary carbohydrate intake to a level that results in nutritional ketosis (i.e., circulating ketone levels >0.5 mmol/L) while increasing fat intake for a period of several weeks. The coordinated set of metabolic adaptations that ensures proper interorgan fuel supply in the face of low-carbohydrate availability is referred to as keto-adaptation. Beyond simply providing a stable source of fuel for the brain, the major circulating ketone body, beta-hydroxybutyrate, has recently been shown to act as a signalling molecule capable of altering gene expression, eliciting complementary effects of keto-adaptation that could extend human physical and mental performance beyond current expectation. In this paper, we review these new findings and propose that the shift to fatty acids and ketones as primary fuels when dietary carbohydrate is restricted could be of benefit for some athletes.  相似文献   
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We describe how a team approach that we developed as a mentoring strategy can be used to recruit, advance, and guide students to be more interested in the interdisciplinary field of mathematical biology, and lead to success in undergraduate research in this field. Students are introduced to research in their first semester via lab rotations. Their participation in the research of four faculty members-two from biology and two from mathematics-gives them a first-hand overview of research in quantitative biology and also some initial experience in research itself. However, one of the primary goals of the lab rotation experience is that of developing teams of students and faculty that combine mathematics and statistics with biology and the life sciences, teams that subsequently mentor undergraduate research in genuine interdisciplinary environments. Thus, the team concept serves not only as a means of establishing interdisciplinary research, but also as a means of incorporating new students into existing research efforts that will then track those students into meaningful research of their own. We report how the team concept is used to support undergraduate research in mathematical biology and what types of team-building strategies have worked for us.  相似文献   
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Many formal policies have suggested that officers need a college degree; however, policies forced little change in practices of American police organizations. Six hundred-fifty patrol officers employed in 12 medium-sized police departments in three Midwestern states were surveyed as to their current educational attainment and job performance. The purpose of this study was to determine the relationship between educational level and police performance.  相似文献   
49.
A student's expectation for a positive outcome for their future career development is referred to as career optimism. Career Services, a common university department, utilizes the social cognitive career theory (SCCT) to understand how students form career interests and make educational and vocational choices. Then Career Services can assist students in finding a career that matches their interests. We hypothesize that students' perception of the assistance provided by the Career Services department when the SCCT is applied, impacts the student's career optimism. In addition, we hypothesize, and results support, that different factors, such as a student's chosen major, impact student perception of Career Services and career optimism.  相似文献   
50.
The study examined the moderating role of children's affect-biased attention to angry, fearful, and sad adult faces in the link between interparental conflict and children's distinct forms of involvement. Participants included 243 preschool children (Mage = 4.60 years, 56% female) and their parents from racially (48% African American, 43% White) and socioeconomically (median annual household income = $36,000) diverse backgrounds. Data collection took place in the Northeastern United States (2010–2014). Utilizing a multi-method, multi-informant, longitudinal design, attention away from anger selectively amplified the link between interparental conflict and children's subsequent coercive involvement (β = −.15). Greater attention to fear potentiated the pathway between interparental conflict and children's later cautious (β = .14) and caregiving involvement (β = .15). Findings are interpreted in the context of environmental sensitivity models.  相似文献   
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