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211.
Paul S. R. Goods Brian Dawson Grant J. Landers Christopher J. Gore Kevin Croft Peter Peeling 《European Journal of Sport Science》2016,16(8):1047-1054
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?.001), with a large effect (d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response. 相似文献
212.
Lee Ingle Ashlie Stephenson Gavin R. Sandercock 《European Journal of Sport Science》2016,16(8):1187-1196
The aim of the study was to compare and contrast habitual physical activity (PA) profiles and muscular fitness in schoolchildren from northern and southern regions of England. Data were collected from two secondary schools in the north east (NE) of England. The study procedures followed methods employed by the East of England Healthy Hearts Study in 10–16-year-old boys and girls based in the south east (SE) region of England and data were compared. Habitual physical activity (PAQ-A), vertical jump test, and hand-grip (HG) strength were assessed. We converted raw scores from all assessments to age- and sex-normalised z-scores. We recruited 597 children (58% boys) in the NE and compared findings to 597 age- and sex-matched boys and girls from the SE. Boys in the SE had significantly stronger HG scores, jumped higher, were more powerful (mean peak power: 2131?W vs. 1782?W; P?0.0001), and reported being more physically active (mean PAQ-A: 2.9 vs. 2.5; P?0.0001) than their male counterparts in the NE. In girls, the opposite trend was evident. Girls from the NE of England had a higher HG score, jumped higher, and were more powerful (mean peak power: 2114?W vs. 1839?W; P?.0001) than their peers from the SE. Regional variations in the habitual PA profiles and muscular fitness of schoolchildren from the SE and NE of England do exist. The systematic surveillance of children’s PA and fitness profiles throughout England would help identify regional inequalities on a larger scale. 相似文献
213.
The present paper focuses on the application of a structured template, maximum impact flow (MIF), in order to encourage young students in the area of optics and optical engineering. MIF introduces a template in terms of individual steps and linked functionality and is shown to fuse separate learning tools together into a cohesive unit. Prioritization and teaching structures are also discussed with the promotion of technology identified as a key factor. 相似文献
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OBJECTIVE: The United States General Accounting Office (United States General Accounting Office [USGAO], 1989) report on out-of-home care affirmed that the foster care system is in crisis. To shed light on some factors that influence retention, the study reported here asked "What factors influence the satisfaction of foster parents?" and "What factors influence the intent of licensed foster parents to continue to foster?" METHOD: A sample of 539 foster parents in eight urban counties in a large Midwestern state completed questionnaires aimed at addressing these questions. RESULTS: Some of the factors exerting the strongest influence on satisfaction were: feeling competent to handle the children who were placed; wanting to take in children who needed loving parents; no regrets about investment in foster children; foster mother's age; and agency social worker providing information and showing approval for a job well done. An example of factors exerting influence on intent to continue to foster include overall satisfaction, readiness to phone the social worker, number of foster boys in the home, being treated like one needed help oneself, and agency affiliation (private). CONCLUSIONS: Efforts to increase the supply of foster homes through recruitment is not enough. The support, training, and professional regard given to parents after they have begun the fostering task is of greater need. Based on analysis of the findings, implications for practice, programming, and policy are offered. 相似文献
216.
G Nagendrappa 《Resonance》2005,10(8):80-90
Free radical synthetic methodology has grown by leaps and bounds in just about two decades. The limit to which the scope of
free radical synthesis can go is restricted only by the imagination of the synthetic chemist. It greatly simplifies a synthetic
sequence, makes use of readily available, relatively inexpensive reactants and reagen-ts; the transformations are selective,
involve fewer steps, the yields are good, the reaction conditions are mild, etc. Therefore, such free radical reactions truly
qualify to be called “Green Chemistry”. 相似文献
217.
218.
Research suggests growth mindset, or the belief that knowledge is acquired through effort, may enhance women’s sense of belonging in male-dominated disciplines, like computing. However, other research indicates women who spend a great deal of time and energy in technical fields experience a low sense of belonging. The current study assessed the benefits of a growth mindset on women’s (and men’s) sense of intellectual belonging in computing, accounting for the amount of time and effort dedicated to academics. We define “intellectual belonging” as the sense that one is believed to be a competent member of the community. Whereas a stronger growth mindset was associated with stronger intellectual belonging for men, a growth mindset only boosted women’s intellectual belonging when they did not work hard on academics. Our findings suggest, paradoxically, women may not benefit from a growth mindset in computing when they exert a lot of effort. 相似文献
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