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31.
PurposeThe aim of this study was to evaluate the efficacy of a 17-week, 3-component lifestyle intervention for enhancing health behaviors during the coronavirus disease 2019 (COVID-19) pandemic.MethodsA parallel-group (intervention and control) study was conducted amongst 79 airline pilots over a 17-week period during the COVID-19 pandemic. The intervention group (n = 38) received a personalized sleep, dietary, and physical activity (PA) program. The control group (n = 41) received no intervention. Outcome measures for sleep, fruit and vegetable intake, PA, and subjective health were measured though an online survey before and after the 17-week period. The changes in outcome measures were used to determine the efficacy of the intervention.ResultsSignificant main effects for time × group were found for International Physical Activity Questionnaire-walk (p = 0.02) and for all other outcome measures (p < 0.01). The intervention group significantly improved in sleep duration (p < 0.01; d = 1.35), Pittsburgh Sleep Quality Index score (p < 0.01; d = 1.14), moderate-to-vigorous PA (p < 0.01; d = 1.44), fruit and vegetable intake (p < 0.01; d = 2.09), Short Form 12v2 physical score (p < 0.01; d = 1.52), and Short Form 12v2 mental score (p < 0.01; d = 2.09). The control group showed significant negative change for sleep duration, Pittsburgh Sleep Quality Index score, and Short Form 12v2 mental score (p < 0.01).ConclusionResults provide preliminary evidence that a 3-component healthy sleep, eating, and PA intervention elicit improvements in health behaviors and perceived subjective health in pilots and may improve quality of life during an unprecedented global pandemic.  相似文献   
32.
In a series of three papers, we attempt to evaluate the past scientific performance of the three main particle accelerators at the Geneva-based European Organization for Nuclear Research (CERN) over the period since 1960, and to assess the future prospects for CERN and its users during the next ten to fifteen years.We concerned ourselves in a previous paper (Paper 1 - Martin and Irvine [51] with the position of the CERN accelerators in world high-energy physics relative to those at other large laboratories working in the field. We dealt primarily with the period from 1969 to 1978, and attempted to establish how the experimental output from the three principal CERN accelerators, taken as a whole, compared with that from other major facilities. In undertaking this comparative evaluation, we drew on the method of “converging partial indicators” used in previous studies of three Big Science specialties.In contrast, this paper (Paper II) focuses in detail on the scientific performance of each of the CERN accelerators taken individually. In particular, it asks, first, how the outputs from the CERN 28 GeV (giga or billion electron-volts) Proton Synchrotron compare with those from a very similar 33 GeV American accelerator at Brookhaven National Laboratory over the past two decades? Second, how great have been the experimental achievements of the Intersecting Storage Rings in world terms? And, third, how do the outputs from the CERN 400 GeV Super Proton Synchrotron and from a rival American machine at Fermi National Accelerator Laboratory compare? Attempts are then made to identify the main factors responsible for determining the relative scientific performance of each CERN machine.These factors are of relevance to the subject of a third paper (Paper III - Martin and Irvine [52]) which sets out to assess the future prospects for CERN and in particular for LEP, the large electron-positron collider scheduled for completion in the latter part of the 1980s. What are the construction requirements (financial and technical) associated with LEP, and how easily will they be met? How does the scientific potential of LEP compare with that of other major accelerators under construction around the world? And, in the light of the previous record of the CERN accelerators, to what extent is this potential likely to be realized? The paper concludes with a discussion of the extent to which predictive techniques can be utilized in the formulation of scientific priorities, and of the problems in current science policy-making that such techniques might help address.  相似文献   
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We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula.  相似文献   
35.
我国优秀乒乓球人才流动特征分析   总被引:1,自引:0,他引:1  
通过对新中国成立以来不同时期中国优秀乒乓球人才国内、国外流动方向、范围、规模等方面的研究,探究我国优秀乒乓球人才流动的特征与趋势,结果表明:(1)优秀乒乓球人才流动始终以垂直流动为主要方式;(2)优秀乒乓球人才在国内、国际流动的区域呈现出不均衡的分布趋势;(3)优秀乒乓球人才资源丰富与基层群众文化发展的急需相矛盾、脱节;(4)优秀乒乓球人才职业转换的跨度、范围增大,自主性流动趋势增强;(5)优秀乒乓球人才的流动促进r乒乓球运动全球化整体的发展与提高,推动了中国文化的繁荣与世界文化的全面交融.  相似文献   
36.
The first purpose of this study was to examine the interrelationships among three forms of relational efficacy within performing dyads, namely, self-efficacy, other-efficacy, and relation-inferred self-efficacy. The second objective was to examine the relationships between these efficacy beliefs and athletes' perceptions of their commitment to and satisfaction with their current partnership. Participants were 120 junior tennis players (age, M = 14.30 years, SD = 1.21) performing within 60 intact pairs (i.e., doubles). Results revealed that self-efficacy and other-efficacy were predictive of athlete commitment and satisfaction, respectively. In addition, by utilizing actor-partner interdependence models, partner as well as actor effects were evident. The findings illustrate that relational efficacy beliefs may not only have implications for the individual holding such beliefs, but also for his or her relational partner. Implications for the future study of efficacy beliefs within dyadic contexts are discussed.  相似文献   
37.
中国传媒产业市场结构、行为与绩效分析   总被引:3,自引:1,他引:3  
据摩根斯坦利全球投资报告的统计分析,建立起世界级有竞争力的大企业,传媒业仅需要8年时间,远远快于医药业、银行、电力、能源等行业。可以说,传媒业已经成为继电子信息、制造业、烟草业之后我国排名第四的国家支柱产业,对其产业状况进  相似文献   
38.
The purpose of this study was to investigate the accuracy of fat-free mass (FFM) estimates from two-compartment (2C) models including air displacement plethysmography (ADP), ultrasound (US), near-infrared interactance (NIR), and the Jackson and Pollock skinfold equation (SKF) against a criterion four-compartment (4C) model in elite male rowers. METHODS: Twenty-three elite-level male rowers (mean± SD; age 24.6 ± 2.2 years; stature: 191.4 ± 7.2 cm; mass: 87.2 ± 11.2 kg) participated in this investigation. All body composition assessments were performed on the same day in random order, except for hydrostatic weighing (HW), which was measured last. FFM was evaluated using a 4C model, which included total body water from bioimpedance spectroscopy, body volume from HW, and total body bone mineral via dual-energy X-ray absorptiometry. The major findings of the study were that the 2C models evaluated overestimated FFM and should be considered with caution for the assessment of FFM in elite male rowers. Future studies should use multiple-compartment models, with measurement of TBW and bone mineral content, for the estimation of FFM.  相似文献   
39.
Purpose: Scholarship is essential for the growth and development of the physical education field. Over time, scholarship expectations have changed, forcing faculty members to alter time spent for research, teaching, and service. Social-cognitive career theory (SCCT) presents a model for understanding performance and persistence in an occupational environment. The interconnected aspects of SCCT have different emphasis related to self-efficacy, outcome expectations, or personal goals pursuit. This study explored physical education teacher education (PETE) faculty members’ continuing engagement in scholarly activity through SCCT. Method: Data collection included interviews with 9 senior PETE faculty members who met the criteria for “productive scholars over time.” Curriculum vitae were collected to verify productivity. Results: Data analysis revealed guidepost themes that included collaborating, finding balance, defining a research process, and maintaining a strong work ethic. Roadblocks encountered included other obligations and lack of support for research. Conclusions: Participants demonstrated strong self-efficacy; held high, positive expectations for success; and set very specific, clear, and deliberate goals. Participant behavior was moderated by their personal attributes (capacity to build relationships, set goals, and maintain interest and passion) and was tempered by the environments in which they worked. Fostering similar behaviors has the potential to guide future and current PETE faculty members in creating supportive and encouraging atmospheres for sustained productivity. The lack of literature relating to this topic warrants the need for more research exploring the influential factors and benefits gained from sustained scholarly productivity over time for PETE faculty members.  相似文献   
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