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11.
According to the statistics of the World Health Organization, an estimated 17.9 million people die from cardiovascular diseases each year, representing 31% of all global deaths. Continuous non-invasive arterial pressure (CNAP) is essential for the management of cardiovascular diseases. However, it is difficult to achieve long-term CNAP monitoring with the daily use of current devices due to irritation of the skin as well as the lack of motion artifacts suppression. Here, we report a high-performance skin-like optoelectronic system integrated with ultra-thin flexible circuits to monitor CNAP. We introduce a theoretical model via the virtual work principle for predicting the precise blood pressure and suppressing motion artifacts, and propose optical difference in the frequency domain for stable optical measurements in terms of skin-like devices. We compare the results with the blood pressure acquired by invasive (intra-arterial) blood pressure monitoring for >1500 min in total on 44 subjects in an intensive care unit. The maximum absolute errors of diastolic and systolic blood pressure were ±7/±10 mm Hg, respectively, in immobilized, and ±10/±14 mm Hg, respectively, in walking scenarios. These strategies provide advanced blood pressure monitoring techniques, which would directly address an unmet clinical need or daily use for a highly vulnerable population.  相似文献   
12.
为中国足球减压———基于国人过高期望的反思   总被引:2,自引:1,他引:1  
在我们发泄着对中国足球的各种不满与愤怒的时候,我们也应该思考一下这些不满的根源在何处,也应该反思一下这种愤怒是否真的有助于中国足球的发展.正是基于这种思考,通过查阅相关文献和资料,批判性地思考国人对中国足球期望过高的因为和根源,同时反思了这种沉重的压力所带来的负面影响,从而提出为中国足球减压的倡议.同时呼吁国人:合理地定位中国足球,纠正急于求成的冒进行为,理性地分析中国足球在发展中遇到的挫折,循序渐进地发展中国足球.  相似文献   
13.
高校青年教师所处的特殊位置、环境和所担当的特殊角色、使命,使其在社会变革和转型过程中承受着多方面的心理压力,需要社会、学校、家庭和教师本人共同努力,采取切实措施进行有效疏导、调适和应对。  相似文献   
14.
Rankine理论和Coulomb理论均不适合用于浅圆仓的侧压力计算. 基于此, 本文研究了浅圆仓散料侧压力的实际分布规律及计算方法. 根据极限平衡理论, 首先得到散粒体作用在单位周长的仓壁上的合压力, 然后通过严格的数学推导, 得到浅圆仓侧压力的分布规律. 结果表明, 本文结果与实仓试验结果相符, 说明本文公式不论对平堆还是锥堆都比较适合, 而Rankine理论和Coulomb理论用于浅圆仓均有缺陷.  相似文献   
15.
This article focuses on raising concern that anxiety–performance relationship theory has insufficiently catered for motoric issues during, primarily, closed and self-paced skill execution (e.g., long jump and javelin throw). Following a review of current theory, we address the under-consideration of motoric issues by extending the three-dimensional model put forward by Cheng, Hardy, and Markland (2009) (‘Toward a three-dimensional conceptualization of performance anxiety: Rationale and initial measurement development, Psychology of Sport and Exercise, 10, 271–278). This fourth dimension, termed skill establishment, comprises the level and consistency of movement automaticity together with a performer's confidence in this specific process, as providing a degree of robustness against negative anxiety effects. To exemplify this motoric influence, we then offer insight regarding current theories’ misrepresentation that a self-focus of attention toward an already well-learned skill always leads to a negative performance effect. In doing so, we draw upon applied literature to distinguish between positive and negative self-foci and suggest that on what and how a performer directs their attention is crucial to the interaction with skill establishment and, therefore, performance. Finally, implications for skill acquisition research are provided. Accordingly, we suggest a positive potential flow from applied/translational to fundamental/theory-generating research in sport which can serve to freshen and usefully redirect investigation into this long-considered but still insufficiently understood concept.  相似文献   
16.
经过对多风机通风网络分析,利用现有的VNETPC模拟程序,建立了多风机风压优化计算机调节系统.该系统允许计算机自动调整多风机风压,直到各用风地点获得最佳可接受的风量分配为止.  相似文献   
17.
便携式多参数监护仪的研制   总被引:3,自引:0,他引:3  
本介绍了一种便携式人体多参数监护仪的研制方法,包括:心电检测、血压检测、血氧饱和度检测、呼吸检测模拟电路的设计,以及存储单元、A/D转换器、USB通讯口等接口模块的设计。  相似文献   
18.
Abstract

This qualitative study investigated the negative impacts minority teacher candidates receive from white teacher candidates in a required multicultural education class. The findings reveal that four teacher candidates of color had difficulty positioning themselves among the overwhelming silencing power of whiteness in the class. The white students were tactful at evading power and race and flattening the existing hierarchical power relations through the discourses of colorblindness and by preying on the minority instructor. Their understanding of diversity was also shallow. On the other hand, the teacher candidates of color were afraid that they might be labeled as the ones who spoke up against the white students and fearful of the possibility of retaliation and ostracism from the white peers. It seems that the teacher education program’s structure allowed the white candidates to impose strong negative peer pressure on the teacher candidates of color.  相似文献   
19.
新课程改革中教师心理压力探析   总被引:8,自引:0,他引:8  
新一轮基础教育课程改革在为教师提供更为广阔的发展空间的同时,也给教师的心理带来极大的压力,主要表现为由新旧理念的撞击、教师权威的重构、教师素质的重塑、课程资源的匮乏、教育评价的滞后等因素而引发的矛盾、抵制、失落、沮丧、危机、恐慌等消极心理反应。正确理解教师在新课程实施中产生的这些心理压力,并采取有效的措施缓解其心理压力能确保课程改革的有效实施。  相似文献   
20.
针对液压泵在试验中成批出现零流量压力急剧增大的故障现象,从液压泵的工作原理出发对其进行分析,找到了故障原因,并采取了相应的措施,使故障有效排除,从根本上解决了生产中的疑难问题.  相似文献   
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