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1.
为了有效促进学生武术核心素养的培育,针对我国武术教学中存在套路内容“繁难”、教法单一、重“形”轻“击”、重知识灌输,轻自主性培养、重教师的“教”,轻学生的“学”“学生不喜欢武术课”等一系列问题,提出了有效促进武术认知、武术运动能力、武术人格培育的原则,基于此原则,对“化难为易”策略、“化浅为深”策略、“化无趣为有趣”策略、“化技术为实践”策略、“知新温故”等策略进行了具体探索性设计,并对上述策略的具体实施方法进行了阐述,为中小学武术教学改革提供现实指导。  相似文献   
2.
垂直缠绕攀爬的蛇形机器人是基于模块化的P_R(pitch_roll)关节,以串行总线舵机作为关节驱动装置,其控制系统采用协调级和执行级配合的二级结构,以空间三连杆组成的蠕动爬行作为基本步态,实现了蛇形机器人具有垂直缠绕攀爬的功能。  相似文献   
3.
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses.  相似文献   
4.
ABSTRACT

For many forcefully displaced people worldwide, notions around one’s sense of “home” and “place” in the world are perpetually unsettled. This article explores how digital technologies interact with embodied, material experiences within the geographical location refugees are residing in. Empirical examples from ethnographic research conducted among Iraqi urban refugees, living in prolonged uncertainty in Jordan, shows how situated experiences of legal, material, and social uncertainty reinforce particular mediated socialities. Pivotal studies have shown how digital connections engender virtual home-making practices and a wide variety of connected presences. This study points to the other side of the same coin: the cultivation of “absent presence.” “Absent presence” refers to feelings—the ambivalence that experiences of prolonged displacement bring about—but also to active disengagement and affective tactics in response. These engender a further separation from the physical world where forced migrants are not deemed welcome.  相似文献   
5.
The emerging creative practices of digital collections are increasing in prominence thanks to the access to, and appeal of, data visualizations. Interactive data visualizations, such as a map, timeline, chart, graph, or artist’s rendering of data, enable users to pursue their own research interests within a collection and participate in new areas of research. Use of these data visualizations enhances the scope of the collection and enables a modern and diverse thematic collection to emerge. This article considers the question: Does the addition of data visualizations affect how users participate with a research collection? Impacts on collection development, application of user-centered design, and analysis of users’ exploratory strategies are discussed. Examples of data visualizations used in digital humanities projects and digital collections are presented as case studies.  相似文献   
6.
心血管疾病(cardiovascular disease,CVD)是包括动脉粥样硬化、心力衰竭、心脏缺血后再灌注损伤和心肌梗死等血管和心脏的复杂病症。血管内皮细胞、平滑肌细胞和心肌细胞生理功能障碍是诱发CVD的关键因素。研究表明,运动能够对心脏和动脉的形态、功能起到积极的调控作用,可作为CVD非药物疗法的重要手段之一。运动可通过调控多种运动因子的表达水平,如肌肉分泌的Fstl1、Irisin和MSTN,脂肪分泌的Omentin、Apelin、CTRP3和CTRP9,肝脏分泌的FGF21、ANGPTL3和ANGPTL4等,进而调控血管内皮细胞、平滑肌细胞和心肌细胞的分化、增殖和凋亡,从而发挥其防治CVD作用。本文试图梳理肌肉、脂肪和肝脏分泌的运动因子与调控心脏和动脉功能之间的相关信号通路及其机制,为运动干预防治CVD提供新的思路。  相似文献   
7.
Children are sensitive to a number of considerations influencing distributions of resources, including equality, equity, and reciprocity. We tested whether children use a specific type of reciprocity norm—market norms—in which resources are distributed differentially based strictly on amount offered in return. In two studies, 195 children 5–10 years and 60 adults distributed stickers to friends offering same or different amounts of money. Overall, participants distributed more equally when offers were the same and more unequally when offers were different. Although sensitive to why friends offered different amounts of money, children increasingly incorporated market norms into their distributions with age, as the oldest children and adults distributed more to those offering more, irrespective of the reasons provided.  相似文献   
8.
9.
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties.  相似文献   
10.
运动性疲劳的细胞机制及研究进展   总被引:18,自引:0,他引:18  
运动性疲劳是一个十分复杂的过程,并受到多种因素的影响,迄今为止人们对其产生的机理仍未达成一致的看法。本文就运动性疲劳的机制问题对近几年来研究的热点及最新进展情况试作阐述。  相似文献   
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