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71.
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   
72.
《开元天宝遗事》为宋前记载唐开元天宝年间重要史料的笔记小说,学界目前有两种观点:一、洪迈认定为伪作,并否定其价值;二、《四库全书总目》以苏轼《开元天宝遗事四绝句》及司马光《资治通鉴》有"张彖指杨国忠为冰山语"为证,为《开元天宝遗事》辩护。经考证苏轼所作诗与此书无关,"张彖指杨国忠为冰山语"亦见于孔平仲《续世说》,与司马光同时,疑另有渊源。《四库全书总目》观点不足取,洪迈之说当可信。洪迈之言记录此书较早成书流传情况,且《遗事》的成书与流播,反映了早期笔记小说成书过程中不断被增扩的轨迹,进一步印证《总目》所言有失。  相似文献   
73.
Giving parents a choice with regard to their children's education has been central to the political discourse of school reform at least since the 1988 Education Reform Act (ERA). With regard to children with a Statement of special educational needs (SSEN), a plethora of policies and laws have given parents the right not only to choose a school, but also to appeal to decisions in the best interest of their children. Yet, despite the discourse of school choice, the implementation and practice of such reforms is neither assured nor simple. Participants in this study indicated that they have little choice of suitable provision and are having to compromise either the academic or the social aspects of their child's schooling. This article argues that for many parents whose children have a Statement of SEN, the choice of a school is often a dilemma, as ‘nowhere seems to fit’.  相似文献   
74.
Problem solving represents a salient deficit in students with mathematical learning difficulties (MLD) primarily caused by difficulties with informal and formal mathematical competencies. This study proposes a computerized intervention tool, the integrated dynamic representation (IDR), for enhancing the early learning of basic mathematical competencies and word problem solving skills. The goal was to compare and contrast the effects of IDR on the acquisition of informal and formal mathematical competencies in students with attention deficit/hyperactivity disorder (ADHD) and MLD. Participants were 216 students (6–9 years), who were classified into three groups: ADHD (n = 72), MLD (n = 82), ADHD and MLD (n = 62). They completed the Test of Early Mathematics Ability (Third Edition). The results showed that all three diagnosed groups improved significantly postintervention in all mathematical competencies, with the MLD‐only group benefiting the most at posttest.  相似文献   
75.
76.
Abstract

Students develop robust mental models of teaching and learning during their school years, and as such, often teach as they were taught—possibly perpetuating practices that limit intellectual inquiry in classrooms. This paper reports on an analysis, using a conceptual framework and NUD?1ST software, of a cohort of 3rd‐year teacher education students' reflections on changes in their mental models following their experiences in a problem‐based learning (PBL) topic. Results provide evidence that students do report changing mental models in areas such as (a) the value of case studies for engaging with subject content, motivating learning, and connecting theory with practice; (b) self‐reflection and peer collaboration for cognitive and professional growth; and (c) processes of inquiry for developing self‐regulated learning practices.  相似文献   
77.
78.
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   
79.
ABSTRACT

This paper considers the examination results of TVEI and non TVEI pupils in the database established at the University of Newcastle in 1985‐87. The pupils took national exams in the summer of 1987, when they were about 16 years old. Their average grades (Exam Means) and their accumulated grades (Exam Totals) were considered separately.

The Exam Mean and Exam Total scores were generally worse for TVEI than non TVEI pupils, even when pupils with the same ability test scores and aspirational scores were compared. However, it is possible that non TVEI factors caused the discrepancy in results and it is these factors which are the subjects of this paper.

The paper considers firstly whether the differences are an artefact of regression analysis. Secondly, the data are considered using various multilevel models. Both analyses suggest that there was no TVEI effect on the Exam Mean score and a negative TVEI effect on the Exam Total. Various explanations for these findings, concerning internal school allocational and curriculum policies, are considered and discussed.  相似文献   
80.
Abstract

This article describes the questionnaire by which the Austrian Ministry of Education investigated the state of media education in primary schools, and briefly summarizes the results. It then describes the teaching materials that have been and are being produced.  相似文献   
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