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61.
Caffeine and coffee are widely used among active individuals to enhance performance. The purpose of the current study was to compare the effects of acute coffee (COF) and caffeine anhydrous (CAF) intake on strength and sprint performance. Fifty-four resistance-trained males completed strength testing, consisting of one-rep max (1RM) and repetitions to fatigue (RTF) at 80% of 1RM for leg press (LP) and bench press (BP). Participants then completed five, 10-second cycle ergometer sprints separated by one minute of rest. Peak power (PP) and total work (TW) were recorded for each sprint. At least 48 hours later, participants returned and ingested a beverage containing CAF (300?mg flat dose; yielding 3–5?mg/kg bodyweight), COF (8.9?g; 303?mg caffeine), or placebo (PLA; 3.8?g non-caloric flavouring) 30 minutes before testing. LP 1RM was improved more by COF than CAF (p?=?.04), but not PLA (p?=?.99). Significant interactions were not observed for BP 1RM, BP RTF, or LP RTF (p?>?.05). There were no sprint?×?treatment interactions for PP or TW (p?>?.05). 95% confidence intervals revealed a significant improvement in sprint 1 TW for CAF, but not COF or PLA. For PLA, significant reductions were observed in sprint 4 PP, sprint 2 TW, sprint 4 TW, and average TW; significant reductions were not observed with CAF or COF. Neither COF nor CAF improved strength outcomes more than PLA, while both groups attenuated sprint power reductions to a similar degree. Coffee and caffeine anhydrous may be considered suitable pre-exercise caffeine sources for high-intensity exercise.  相似文献   
62.
The aims of this study were to describe normative values and seasonal variation of body composition in female cyclists comparing female road and track endurance cyclists, and to validate the use of anthropometry to monitor lean mass changes. Anthropometric profiles (seven site skinfolds) were measured over 16 years from 126 female cyclists. Lean mass index (LMI) was calculated as body weight?×?skinfolds?x. The exponent (x) was calculated as the slope of the natural logarithm of body weight and skinfolds. Percentage changes in LMI were compared to lean mass changes measured using dual-energy X-ray absorptiometry (DXA) in a subset of 25 road cyclists. Compared to sub-elite and elite cyclists, world class cyclists were (mean [95% CI]) 1.18?kg [0.46, 1.90] and 0.60?kg [0.05, 1.15] lighter and had skinfolds that were 7.4?mm [3.8, 11.0] and 4.6?mm [1.8, 7.4] lower, respectively. Body weight (0.41?kg [0.04, 0.77]) and skinfolds (4.0?mm [2.1, 6.0]) were higher in the off-season compared to the early-season. World class female road cyclists had lower body weight (6.04?kg [2.73, 9.35]) and skinfolds (11.5?mm [1.1, 21.9]) than track endurance cyclists. LMI (mean exponent 0.15 [0.13, 0.18]) explained 87% of the variance in DXA lean mass. In conclusion, higher performing female cyclists were lighter and leaner than their less successful peers, road cyclists were lighter and leaner than track endurance cyclists, and weight and skinfolds were lowest early in the season. LMI appears to be a reasonably valid tool for monitoring lean mass changes.  相似文献   
63.
The present study examined the sex-specific associations of moderate and vigorous physical activity (VPA) with physical fitness in 300 Japanese adolescents aged 12–14 years. Participants were asked to wear an accelerometer to evaluate physical activity (PA) levels of various intensities (i.e. moderate PA (MPA), 3–5.9 metabolic equivalents (METs); VPA, ≥6 METs; moderate to vigorous PA (MVPA), ≥3 METs). Eight fitness items were assessed (grip strength, bent-leg sit-up, sit-and-reach, side step, 50?m sprint, standing long jump, handball throw, and distance running) as part of the Japanese standardised fitness test. A fitness composite score was calculated using Japanese fitness norms, and participants were categorised according to their score from category A (most fit) to category E (least fit), with participants in categories D and E defined as having low fitness. It was found that for boys, accumulating more than 80.7?min/day of MVPA may reduce the probability of low fitness (odds ratio (ORs) [95% confidence interval (CI)]?=?0.17 [0.06–0.47], p?=?.001). For girls, accumulating only 8.4?min of VPA could reduce the likelihood of exhibiting low fitness (ORs [95% CI]?=?0.23 [0.05–0.89], p?=?.032). These results reveal that there are sex-specific differences in the relationship between PA and physical fitness in adolescents, suggesting that sex-specific PA recommendation may be needed to improve physical fitness in adolescents.  相似文献   
64.

Objective

“One Health” is an interdisciplinary approach to evaluating and managing the health and well-being of humans, animals, and the environments they share that relies on knowledge from the domains of human health, animal health, and the environmental sciences. The authors'' objective was to evaluate the extent of open access (OA) to journal articles in a sample of literature from these domains. We hypothesized that OA to articles in human health or environmental journals was greater than access to animal health literature.

Methods

A One Health seminar series provided fifteen topics. One librarian translated each topic into a search strategy and searched four databases for articles from 2011 to 2012. Two independent investigators assigned each article to human health, the environment, animal health, all, other, or combined categories. Article and journal-level OA were determined. Each journal was also assigned a subject category and its indexing evaluated.

Results

Searches retrieved 2,651 unique articles from 1,138 journals; 1,919 (72%) articles came from 406 journals that contributed more than 1 article. Seventy-seven (7%) journals dealt with all 3 One Health domains; the remaining journals represented human health 487 (43%), environment 172 (15%), animal health 141 (12%), and other/combined categories 261 (23%). The proportion of OA journals in animal health (40%) differed significantly from journals categorized as human (28%), environment (28%), and more than 1 category (29%). The proportion of OA for articles by subject categories ranged from 25%–34%; only the difference between human (34%) and environment (25%) was significant.

Conclusions

OA to human health literature is more comparable to animal health than hypothesized. Environmental journals had less OA than anticipated.Keywords (Medical Subject Headings) Publishing, Periodicals as Topic, Access to Information, Veterinary Medicine, Environment, Environmental Health, Medicine“One Health” is an integrated, transdisciplinary approach to solve complex problems at the diverse interfaces shared by humans, animals, and the environment [1]. The One Health approach to evaluating and managing the health and well-being of humans, animals, and the environments that they share relies on knowledge from the domains of human health, animal health, and the environmental sciences. Although there is a growing body of literature about the development of the One Health concept as documented by Pepper, Carrigan, Shurtz, and Foster [2], this literature is not the same as the combination of literature from the three domains that is applied in service of One Health. Every discipline related to One Health has its unique mindset and language, with corresponding lists of acronyms that are frequently an impediment to effective communication across the participating professions. Relevant papers guiding a One Health approach may never specifically use “One Health” as a term or concept.To promote better communication and collaboration among health professionals and environmental scientists, a public monthly One Health Intellectual Exchange Group (IEG) hosted by the North Carolina Biotechnology Center was launched in 2009. In 2011, faculty from the North Carolina State University College of Veterinary Medicine, University of North Carolina''s Gillings School for Global Public Health, Duke Global Health Institute, and Nicholas School of the Environment at Duke University expanded the IEG series into a weekly seminar course with eight One Health focus areas [3]. The eight focus area modules were the following: an introduction to One Health; environmental health and ecology; the human and animal bond; zoonoses and emerging infectious diseases; food and water safety; disease surveillance, informatics, and disaster preparedness; benefits of comparative medicine; and policy and education (Appendix A, online only). Each seminar speaker recommended papers to read prior to the session to provide a foundation for the topic because student backgrounds and majors were quite diverse. Represented student majors included master''s of public health, master''s of animal science, doctor of veterinary medicine, graduate-level environmental sciences, and undergraduate-level biochemistry, engineering, and biology.Open access (OA) to relevant literature is very important to scholars and practitioners working on interdisciplinary problems. The One Health Proof of Concept Workgroup found that few studies assess outcomes in human, animal, and environmental spheres simultaneously [4], making it important to be able to access articles from each of the three domains to get a more complete picture.The objective of this study was to evaluate the extent of OA to journal articles in a sample of literature relevant to One Health from the human, animal, and environmental domains. Working in a college of veterinary medicine and supporting faculty, staff, and students addressing interdisciplinary problems under the One Health umbrella [5], the authors were familiar with the extent of OA in human biomedical and public health literature and the literature of veterinary medicine but were less familiar with environmental journals. In light of general availability of environmental information and OA to publications such as Environmental Health Perspectives, we thought it likely that environmental literature would be relatively open compared to the other subject areas. Therefore, we hypothesized OA to articles from human health or environmental journals was greater than access to animal health literature. We chose to look at article-level subject categorization and access, as well as journal-level categorization and access, because they might differ. Article-level access relates more to authors'' decisions about OA for a content domain, while journal-level access and subject categorization are driven by publishers and associations. Understanding the distinction and having data would inform our efforts to promote increased OA to this literature.  相似文献   
65.
残障儿童的父母.是孩子一生最好的教育者,因为他们在孩子成长的过程中无私奉献,恪尽责任。对那些有残障儿童的家庭而言.“知识就是力量”这句话就是真理。这些家长需要掌握关于残障症状的特点、教育治疗方案和策略等信息,以提升日常生活质量。家长们也想知道什么样的服务最适合孩子.如何获得这些服务.如何定位家长角色以确保孩子的进步.[第一段]  相似文献   
66.
67.
The authors examined second grade reading accuracy and fluency and their associations via letter knowledge to phonological and language predictors assessed at 3.5, 4.5, and 5.5 years in children in the Jyv?skyl? Longitudinal Study of Dyslexia. Structural equation modeling showed that a developmentally highly stable factor (early phonological and language processing [EPLP]) behind key dyslexia predictors (i.e., phonological awareness, short-term memory, rapid naming, vocabulary, and pseudoword repetition) could already be identified at 3.5 years. EPLP was significantly associated with reading and spelling accuracy and by age with letter knowledge. However, EPLP had only a minor link with reading fluency, which was additionally explained by early letter knowledge. The results show that reading accuracy is well predicted by early phonological and language skills. Variation in fluent reading skills is not well explained by early skills, suggesting factors other than phonological core skills. Future research is suggested to explore the factors behind the development of fast and accurate decoding skills.  相似文献   
68.
69.
The article explores the communication of data to schools by researchers and evaluators. The stance is taken that the research process is one in which the participants are involved in a mutually supportive enterprise in which the relationship should be viewed as co-operation between professional colleagues, i.e., a relationship in which perceived status is minimised but one in which different knowledge and expertise exists on both sides. It is argued that the obtaining of data at school sites requires the researcher to provide data to their sources. Careful consideration needs to be given by researchers to the process and methods of communication of data to school communities. Issues addressed include audience, terminology, prose and other forms of presentation. A case is made for the researcher to become involved in dialogue to enhance the “meaning-making” of practitioners and themselves. The article concludes with a set of guidelines for researchers.  相似文献   
70.
This article reports on teachers' reactions to a pilot implementation of a new standards-based teacher evaluation system in a medium-sized Midwestern school district. The system, based on the Framework for Teaching (Danielson, 1996), was intended to serve as the foundation for a new knowledge and skill pay plan for teachers. Teacher reactions were measured using both interview and survey methods. Teachers' overall favorableness toward the system, as measured by the survey, was correlated with acceptance of the teaching standards, perception of the evaluation process as fair and the evaluator as capable and objective, and perception that the evaluation system had a positive impact on their teaching. In interviews, teachers perceived both positive and negative aspects of the system, and for many these more or less balanced each other. While most teachers accepted the evaluation standards and the need for an evaluation system, many also perceived that the system added too much to teachers' workloads and did not provide enough feedback. Based on these results several changes were made in the evaluation system prior to full implementation. The results are discussed with reference to previous research and the Personnel Evaluation Standards.  相似文献   
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