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101.
Purpose: This study investigated the effect of summer camp session context on Russian girls’ physical activity (PA). Method: Girls (n = 32, Mage = 10.7 years, SD = 0.6 years) from a resident summer camp taking place in the Vologda Region of Russia were exposed to 1 session context/day (i.e., free play, organized with no choice, organized with choice) on Wednesday, Thursday, and Friday for 3 weeks, with the context order counterbalanced across the 3 weeks. The organized session sport/game changed weekly. The primary outcome was accelerometer-assessed PA. Repeated-measures mixed models were used to analyze all outcome data. Results: Findings showed that girls spent a greater percentage of session time (%time) in moderate-to-vigorous PA (p < .001; effect sizes between free play and organized with no choice and organized with choice, respectively = .60, .42) and moderate PA (p < .001; effect size = .57, .39) and a lower %time in light PA (p < .001; effect size = .55, .52) in organized PA contexts compared with free play. Conclusions: This study provides novel findings in a Russian setting, suggesting that a well-planned, organized camp session can elicit higher PA levels in girls, relative to a free-play session.  相似文献   
102.
产业聚集形成的集聚效应可以大大提升产业生产效率,对区域的经济发展具有很强的拉动作用.我国自20世纪80年代开始,在沿海地区开始进行产业集聚生产模式的发展,在取得巨大经济利益的基础上,同时也建立了以产业集聚为基础的科技创新平台,形成具有较强创新能力的科技创新网络.基于此,从产业集聚角度分析影响区域创新能力的运行机理,有着较强的实践意义,也可以为区域经济发展提供一定的理论参鉴.  相似文献   
103.
Purpose: The benefits of physical activity (PA) in preventing abdominal obesity are well recognized, but the role of different sport disciplines remains open. We aimed, therefore, to investigate how participation in different sport disciplines, and the number and types of sports engaged in are associated with waist circumference (WC) in young adulthood. Methods: This population-based cohort study comprised 4027 Finnish twin individuals (1874 men), with a mean age of 34 y (32–37), who answered a survey, including self-measured WC. We extracted the number and identified the types (aerobic, power, and mixed) of the different sport disciplines respondents reported participating in. Results: The number of sport disciplines participated in was inversely associated with WC, the linear decrease averaging 1.38?cm (95% CI 1.10–1.65) per each additional sport discipline. The result persisted after adjustment for the main covariates, such as volume of PA and diet quality. Among dizygotic twin pairs discordant for sports participation (0–2 vs. 5 or more disciplines), the mean within-pair difference in WC was 4.8?cm (95% CI 0.4–9.1) for men and 11.2?cm (95% CI 4.4–18.0) for women; among discordant monozygotic pairs, no differences were observed. In men, all three types of sports were individually associated with smaller WC, while in women, only mixed and power sports showed this association. Conclusions: Participation in several sport disciplines and sport types was associated with smaller WC among young adults in their mid-30s. Shared genetic background may explain some of the associations.  相似文献   
104.
通过"亚住高训"交替训练实验,对12分钟极限跑运动中动态心率、血氧饱和度、"极点"等指标进行研究,探讨"亚住高训"模式对"极点"等指标的影响及其提高中长跑运动员有氧工作能力及运动成绩的新途径.方法:对8名大学生中长跑运动员进行6周"亚住高训"实验研究.测试实验前、中、后期的12分钟极限跑、运动中心率、运动中血氧饱和度等指标,并根据运动生理学原理划分12分钟极限跑中机能变化相对应的"极点"等指标及其持续时间.结果:(1)"亚住高训"交替训练前、中、后,12分钟极限跑成绩、最大摄氧量、运动中心率及血氧饱和度等指标变化,呈现有利于有氧工作能力提高的趋势,部分指标存在显著性差异(P<0.05).(2)"亚住高训"实验后,运动员赛前训练12分钟极限跑的"极点"及其持续时间明显缩短、"第二次呼吸"时间延长、"终点冲刺"时间增加,部分指标存在显著性差异(P<0.05).结论:(1)"亚住高训"交替训练能有效提高运动员12分钟极限跑成绩,对运动员有氧工作能力有积极影响.(2)运动中通过心率、血氧饱和度实时检测,能够反映运动中"极点"第二次呼吸"终点冲刺"等指标的变化规律.(3)"亚住高训"交替训练能对12分钟极限跑过程中"极点"第二次呼吸"终点冲刺"及其持续时间的分配进行干预,有助于中长跑运动成绩的提高.  相似文献   
105.
106.
The aim of the work is to set up a methodological approach to verify the effectiveness of the treatments of decayed waterlogged archaeological wood and to point out the proper thermo-hygrometric conditions for its preservation after treatment. The treatments were performed on wood samples of maritime pine (Pinus pinaster Aiton), oak (Quercus sp. caducifolia), elm (Ulmus cf. minor) and strawberry tree (Arbutus unedo L.), obtained from stems pertaining to the original vegetation found in the excavation site of the Ancient Ships in Pisa (Italy), and dated from seventh century BC to second century AD The utilised products were: Polyethylene Glycols (PEG) of various molecular weights, a Polypropylene Glycol (PPG 425), Trehalose (α-D-glucopyranosyl-α-D-glucopyranoside), and their mixtures, and also a Hydroxypropylcellulose (Klucel). The main objective to be pursued by the treatments was considered the stabilisation of the original size and shape of samples. The various steps of this approach were: the execution of a preliminary diagnostic survey on untreated samples; the characterisation of treatment solutions ‘as such’ to establish the property to be monitored during the treatment; the evaluation of the main physical characteristics of wood after the treatment were determined. Among the latter, the coefficient of dimensional stability during the exposure to a series of selected thermo-hygrometric conditions and the retention of consolidants after the treatment. These two measurements allowed the definition of the ‘efficacy of a treatment’, φT, a new parameter firstly utilised in this work. It measures the stabilisation capability of the percent unit of retained product, and its value permits to put in evidence the consolidants that stabilise wood with the lowest amount of product. Conversely, it was not possible to measure the Anti-Shrink Efficiency (ASE), one of the most utilised parameters for the evaluation of treatments, because of the serious distortions and fractures observed in all the heavily degraded untreated samples.  相似文献   
107.
The need of inspecting a masterpiece of fine art without affecting it led to develop non destructive methods of investigation. In the field of art conservation, several diagnostic techniques are being widely used to inspect works of art, giving different but complementary results. The present work deals with two of these methods, reflectography and thermography, both techniques examining objects in the infrared spectrum but in different wavelength bands. Their integrated data potentially provide a powerful tool for mapping hidden features and alterations of artworks. This was confirmed during the inspections of a 13th century panel painting under restoration at the Opificio delle Pietre Dure laboratories (Florence, Italy). A graphical user interface was also designed to aid operators in the field of conservation dealing with the results of the two IR methods. Many options such as image adjustment, comparison, overlaying and transparency variation, in addition to thermographic elaborations, have been made available to users. Imaging data integration provides a multi-layered and multi-spectral representation of the painting that yields a comprehensive diagnosis confirms the anomalies individuation and reduces the ambiguities of information coming from a single diagnostic method.  相似文献   
108.
109.
Response to intervention (RTI) is advocated in elementary school as a system‐wide, multitiered model of academic and behavioral interventions. Middle schools have begun adopting RTI models based on these existing elementary models. This investigation into current middle school RTI practices describes technical aspects as well as some of cultural and contextual issues surrounding implementation. The study included multiple data collection procedures including surveys, discussion groups, phone interviews, and site visits. Although many schools reported substantial progress with implementation, they recognized rigorous implementation of RTI posed such on‐going challenges as changes in staffing, curricular realignments, very limited selections of screening and progress monitoring tools aligned with their curriculum, and scheduling of secondary and tertiary level interventions.  相似文献   
110.
Factors related to grade point average (GPA) are of great importance for students' success. Yet, little is known about the impact of individual differences in emotional reactivity on students' academic performance. We aimed to examine the emotional reactivity–GPA link and to assess whether self‐esteem and psychological distress moderate this relationship. Eighty undergraduate students reported on their GPA, self‐esteem, and psychological distress. Students' pupil radius was monitored during affective picture viewing to assess sympathetic activation in response to emotional stimuli. Cluster analysis on pupil reactivity to pictures identified low, average, and high emotionally reactive students. Regression analyses indicated that profiles of emotional reactivity were associated with GPA. This relationship was moderated by self‐esteem, but not psychological distress. Among students with higher emotional reactivity, those with lower self‐esteem reported poorer GPA. Findings document the importance of differences in students' emotional reactivity and self‐esteem in relation to academic success.  相似文献   
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