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1.
高危险性体育项目相对一般体育项目而言,是具有危险性大、专业技术性强、安全保障要求高等特点的体育活动。我国对高危险性体育项目有一定的法律规制,但存在顶层设计缺失、法律制度之间的冲突与不一致、可操作性不足等问题。这些制度缺陷产生的根源在于对立法必要性的认识不足、立法不作为,缺乏有效的立法监督机制等,现有制度的缺陷与不足会影响我国高危险性体育项目的发展,难以满足人们体育文化活动的需要。鉴于此,我国应逐步完善高危险性体育项目的法律规制,包括完善高危险性体育项目的审定主体,明确经营高危险性体育项目的主体范围、完善高危险性体育项目的行政许可条件、强化高危险体育项目行政监管以及风险防范等。 相似文献
2.
Kym Joanne Price Brett Ashley Gordon Stephen Richard Bird Amanda Clare Benson 《Journal of sports sciences》2020,38(9):970-984
ABSTRACTInterval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations. 相似文献
3.
In relation to teaching and learning approaches that improve student learning outcomes, threshold concepts have generated substantial interest in higher education. They have been described as ‘portals’ that lead to a transformed way of understanding or thinking, enabling learners to progress, and have been enthusiastically adopted to inform teaching approaches and curriculum design. A growing body of literature has critiqued the relevance and applicability of the threshold concept theory and identified threshold concepts relevant to specific disciplines. More recent research has identified how students cross these thresholds and provided measures of the successful acquisition of threshold concepts. This literature synthesis critiques existing evidence on threshold crossing and acquisition to provide a succinct and informative overview of the outcomes to date. Key questions relevant to educators and researchers investigating whether students acquire the threshold concepts associated with their teaching, arose from the literature synthesis. These were: whether or not threshold crossing can be measured; how variation in student learning can be addressed during measurement; tools that can be used for measuring threshold crossing; whether the way units or concepts are taught should alter prior to measurement, and the challenges and limitations of measuring threshold crossing. 相似文献
4.
以一个销售商驱动的低碳再制造闭环供应链为研究对象,用均值-方差刻画风险特性,分析研究低碳产品市场和废旧低碳产品市场均为随机市场需求情境下、零和博弈和集中决策下闭环供应链中,低碳产品销售价、交易价格、低碳废旧产品回收价格等变量和节点企业期望效用及整个链条期望效用的变化规律。研究表明:零和博弈下低碳闭环供应链未能实现优化和协调。最后,设计正向渠道收益共享、逆向渠道风险共担契约,实现低碳再制造闭环供应链的协调,并通过数值仿真和灵敏度分析验证该模型的有效性及实用性。 相似文献
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6.
Pasquale Del Vecchio Gioconda Mele Valentina Ndou Giustina Secundo 《Information processing & management》2018,54(5):847-860
This paper aims to demonstrate how the huge amount of Social Big Data available from tourists can nurture the value creation process for a Smart Tourism Destination. Applying a multiple-case study analysis, the paper explores a set of regional tourist experiences related to a Southern European region and destination, to derive patterns and opportunities of value creation generated by Big Data in tourism. Findings present and discuss evidence in terms of improving decision-making, creating marketing strategies with more personalized offerings, transparency and trust in dialogue with customers and stakeholders, and emergence of new business models. Finally, implications are presented for researchers and practitioners interested in the managerial exploitation of Big Data in the context of information-intensive industries and mainly in Tourism. 相似文献
7.
Philip A. Ebert 《Journal of Adventure Education & Outdoor Learning》2019,19(1):84-95
In this article, I explore a Bayesian approach to avalanche decision-making. I motivate this perspective by highlighting a version of the base-rate fallacy and show that a similar pattern applies to decision-making in avalanche-terrain. I then draw out three theoretical lessons from adopting a Bayesian approach and discuss these lessons critically. Lastly, I highlight a number of challenges for avalanche educators when incorporating the Bayesian perspective in their curriculum. 相似文献
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Since outbreaks in 2003, avian influenza has received a considerable amount of funding and become a controversial science policy issue in various respects. Like in many other global and multidisciplinary societal problems fraught with high levels of uncertainty, a variety of perspectives have emerged over how to “tackle” avian influenza and public voices have expressed concern over how research funds are being allocated. In this article, we document if and how research agendas are being informed by public policy debates. We use qualitative and quantitative approaches to examine the relations between expectations of outcomes of public science and the existing research landscape. Interviews with a cross-section of stakeholders reveal a wide range of perspectives and values associated with the nature and objectives of existing research avenues. We find that the landscape of public avian influenza research is not directly driven by expectations of societal outcomes. Instead, it is shaped by three institutional drivers: pharmaceutical industry priorities, publishing and public research funding pressures, and the mandates of science-based policy or public health organizations. These insights suggest that, in research prioritization, funding agencies should embrace a broad perspective of research governance that explicitly considers underlying institutional drivers. Deliberative approaches in public priority setting might help to make agendas more plural and diverse and thus more responsive to the contested and uncertain nature of avian influenza research. 相似文献
10.
Bastian Carter-Thuillier Víctor López-Pastor Francisco Gallardo-Fuentes 《Infancia y Aprendizaje》2018,41(3):491-535
This study analyses the integration of Mapuche-Huilliche students who participate in a school sport programme based on the teaching for understanding model in a situation of social risk. In this context, 41 students (aged nine to 12) participate, 24 of whom are from the aforementioned ethnic group. To collect data, participant observation was conducted for eight months and group and individual interviews were held. The results show that the Mapuche-Huilliche students recognize themselves as members of the same collective when participating in games associated with their ethnic group. Their main motives for participating in school sport are the teaching approach and the acquisition of social capital. Cooperative learning activities are shown to foster positive interactions with non-Mapuche students. 相似文献