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91.
Haicheng Li Yinji Ma Ziwei Liang Zhouheng Wang Yu Cao Yuan Xu Hua Zhou Bingwei Lu Ying Chen Zhiyuan Han Shisheng Cai Xue Feng 《国家科学评论(英文版)》2020,7(5):849
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
92.
David Alan George Poh-Ling Tan Jeffrey Frank Clewett 《Environmental Education Research》2016,22(1):62-88
Using a participatory learning approach, we report on the delivery and evaluation of a climate change and risk assessment tool to help manage water risks within the agricultural sector. Post-graduate water-professional students from a range of countries, from both developed and emerging economies were involved in using this tool. Our approach included participative learning tools – group discussion, software, and risk matrices. The materials developed met the needs of the students, allowing these students to incorporate their learning and adapt the package of materials for use in their home countries. Analysis of evaluations show that the tools and materials are particularly useful and emphasizes the need for sound learning materials and tools, funding to deliver training, and policy support to accelerate education and adoption of authentic climate change adaptation practices. The expected benefits for water professionals about climate change will be translated into improved socioeconomic and environmental outcomes if adopted. 相似文献
93.
94.
To alleviate teachers’ reluctance toward practical work, there has been much discussion on teachers’ pedagogical content knowledge, teaching materials, and failsafe strategies for practical work. Despite these efforts, practical work is still regarded as a challenging task for many elementary science teachers. To understand the complexity of teachers’ conflicts in practical work, this study examines teachers’ ideas about teaching and learning that influence teachers’ decision‐making and action on teaching practical work. More important than knowing technical–rational aspects of practical work is to understand the internal contradictions that teachers have to resolve within themselves regarding their capabilities and beliefs about science teaching and practical work. Using stories and experiences of 38 third‐year university students in a science method course in Korea, we seek to understand the conflicts and negotiations that they experience as they make decisions regarding practical work throughout their course. Reflective writings and group discussions on their lived experiences and concerns were used to probe participants’ ideas on teaching using practical work. From written and verbal data, themes were saturated in terms of the aspects which could (dis)encourage their practice. Results suggest that there are multifactorial challenges in pre‐service teachers’ understandings and concerns in practical work. Besides time, materials, and curriculum, pedagogical assumptions and values also compositely challenge the minds of teachers. As the pre‐service elementary teachers negotiated within themselves the importance of science in classroom and social levels, the question is raised about their identities as pre‐service elementary teachers to appreciate the balance between science teaching and practical work. 相似文献
95.
基于计算流体力学CFD软件,建立了数值模型,并对工业厂房的风环境进行了模拟,分析了办公建筑不同的孔洞开启方案对工业厂房通风的影响。研究结果表明:倾角为60°的倾斜孔洞和中心高度为12m的孔洞可以使工业厂房通风效果达到最佳状态。在此基础上,优化了孔洞的设置方式,并结合模拟进行了验证,为工业厂房类建筑通风设计提供决策参考。 相似文献
96.
农村留守儿童问题研究:现状与前瞻 总被引:7,自引:0,他引:7
近年来,农村留守儿童问题已逐渐成为媒体和学术界关注的焦点。然而,目前的研究无论理论上还是实践中均显不足。本文梳理了不同学科在这一问题上的研究成果,揭示尚待研究的问题域。 相似文献
97.
本文以高级技工学校专业英语课程的复合型管理为理念,对高级技工学校专业英语课程的特点进行阐述并对现行的专业英语课程管理的利弊进行分析。在此基础上,对专业英语复合型管理的概念及途径进行论述,进一步阐明在高级技工学校专业英语课程复合型管理的意义,以期达到对高级技工学校外语课程的全面构建与管理。 相似文献
98.
一、几种文化因素的分析与例证(一)语言表达差异因素。每一种语言的表达方式都有其文化的内涵。这种文化的内涵反映了同一种文化中的人们的共同习得。也就是说,不同的文化有其不同的语言表达方式。这种语言表达的差异性正是我们在英文写作时必须注意和必须学会正确使用的地方所 相似文献
99.
应用微分方程定性理论及分支理论分析Z6 等变系统的奇点及其Hamilton,并给出怎样比较Hamilton量大小的一种方法 相似文献
100.
《反对本本主义》:毛泽东思想形成的主要标志 总被引:1,自引:0,他引:1
所谓毛泽东思想的形成是指毛泽东思想的基本形态,也就是其主体部分和“活的灵魂”已经形成。从这一判断标准出发,在详细考察以毛泽东为代表中国共产党人的革命活动和理论贡献的基础上,可以看出《反对本本主义》的发表标志着毛泽东思想已基本形成。 相似文献