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1.
ABSTRACT

The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 m·s?1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmol·L?1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8–11; B[La], 0.8–1.0; CMJ height, 1.6–2.0; CMJ PPO, 1.0–1.8; CMJ PCV, 0.04–0.06; CMJ 100ms-Impulse, 5.7–11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented.  相似文献   
2.
Recent theories suggest that negative effects of fatigue on performance are determined by perception of effort and motivation rather than being directly caused by reaching physiological limits. In the current experiment, the influence of motivation on fatigue-induced decrements in soccer performance was experimentally investigated. Sixty amateur soccer players performed a validated soccer-passing test before and after a fatigue protocol. Results showed that players’ motivation and performance decreased after the fatigue protocol for players in the control group. In contrast, players in the motivation group (i.e., with motivation experimentally induced after the fatigue protocol) were able to uphold their motivation and increase their performance. These results indicate that motivation plays a crucial role in performance under fatigue, as fatigue-induced decrements in soccer passing performance can be counteracted by high levels of motivation. Future research may explore the limits of this counteracting effect and extend findings to other relevant performance aspects.  相似文献   
3.
ABSTRACT

Many museums are housed in historic buildings, sometimes the building itself is part of the museum collection. Creating a stable environment by providing a nearly constant temperature and relative humidity at correct levels decreases the risk of object degradation. Maintaining this steady indoor environment, however, increases energy consumption and risks to the historic building. Museum display cases offer a solution to the mitigation of risks to which valuable objects may be subjected by providing an extra layer of protection to indoor climate fluctuations. The Anne Frank House is a historic house museum located in Amsterdam. The museum has undergone several renovations in the last years to deal with an increase in the number of visitors to over 1.2 million a year. The original diaries and other documents of Anne Frank are permanently on display in the Anne Frank House. With the recent refurbishment the possibility arose to design a new state-of-the-art display case. This study presents the results of the experimental research related to the design, performed in-situ. The temperature and relative humidity in the new exhibition space and inside the new display cases were monitored to gain insight into the hygrothermal behavior of these controlled environments. A complementary numerical study was performed to investigate effects of dynamic climate control of the exhibition gallery and climate conditions in the display case under various circumstances. Four main conclusions are presented in this paper. The investigated display case design is able to provide a stable relative humidity environment by means of silica gel, while using an active box-in-box climate control system to create stable temperature conditions. The inner case temperature depends on the temperature supplied by the display case air handling unit. Protocols must be in place in case of malfunction or failure of the climate control system of the display case. The air handling unit of the case needs to be shut off to create a passive environment for the objects on display until necessary actions are taken. Exhibition gallery set points can be less stringent when susceptible museum objects are on display in the display case. The environments are separated and provide an opportunity for energy saving set point strategies. The last conclusion drawn is that the numerical study provides valuable insight into imposing dynamic control of set points for temperature and relative humidity in the exhibition gallery and the effect on the display case environment.  相似文献   
4.
随着我国社会经济发展,环境保护问题得到社会各界的重视,我国逐渐建立起环境监督与管理体制。美国是发达国家的典型代表,已经建立起相对完善的环境保护法体系和环境监督管理体制,值得我国学习与借鉴。文章通过分析中美环境监督管理体制的特点,比较中美两国环境监督管理机构的职责、独立性、资源配置,以及两国民众环境保护意识的差异,提出了完善我国环境监督管理体制的建议。  相似文献   
5.
Abstract

Institutional repositories (IRs) present platform to disseminate research findings to complement the traditional scholarly communication model. The use of IRs is beneficial to authors, host institutions, libraries and society at large. Despite the numerous benefits of IRs, there is low deposit of scholarly works by lecturers and the investment on IRs seems to be a waste. This study examined determinants of perceived ease of use (PEOU) of IRs by lecturers in Nigerian universities. A survey of lecturers received 857 respondents. Awareness, anchor and adjustment factors were found to be determinants of PEOU of Institutional repositories by lecturers in Nigerian Universities.  相似文献   
6.
This paper examines the long-run relationship between school bullying exposure and later adult health using a nationally representative household survey data from China. Our results show that victims are more likely to have low self-reported health, chronic diseases, physical functional limitations, and mental health problems even after several decades. The negative health consequences are more concentrated on the disadvantaged who come from low-income households or lack family support. The main findings are also consistent with qualitative evidence of our online survey.  相似文献   
7.
物流实验教学团队成员的依存与共进   总被引:1,自引:0,他引:1  
从物流实验教学团队成员的构成、团队群体与个体间的关系以及团队成员间的关系入手,围绕团队氛围对实验教学改革绩效的影响、个体成员对实验教学改革的影响进行探讨的基础上,提出了促进团队成员彼此依存共进的具体措施。  相似文献   
8.
针对当前网络环境下自主学习存在的主要问题,我们利用校园网和现有教育资源构建适合自主学习的平台,结合实践对如何依托此平台建立自主学习方式进行了分析和探讨。  相似文献   
9.
就业是民生之本,创业是经济发展的活力之源,把创业教育纳入高等学校的教育教学体系,培养一大批具有创新、创业精神的企业家,是建设创新型国家的需要,是发展创新型经济的必然要求。研究了企业家及企业家精神的内涵,总结了国内外创业教育的理论和实践,探讨了基于企业家精神的大学生创业能力的培养途径,对高等学校建立创业教育体系,实现国家以创业带动就业的政策具有重要的现实意义。  相似文献   
10.
"实境耦合"人才培养模式是学院在创建国家示范性高等职业院校艰难探索实践中确立的。在此模式下,软件与服务外包学院运用"实境耦合"人才培养模式理论指导其改革实践,从课程设置到训教方法改革等与企业紧密耦合,把学生放在真实的职业环境中,校企合作共同完成了对学生知识、技能、态度的培养,取得了一定成效。  相似文献   
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