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951.
We show, via three-dimensional immersed-boundary-finite-element-lattice-Boltzmann simulations, that deformability-based red blood cell (RBC) separation in deterministic lateral displacement (DLD) devices is possible. This is due to the deformability-dependent lateral extension of RBCs and enables us to predict a priori which RBCs will be displaced in a given DLD geometry. Several diseases affect the deformability of human cells. Malaria-infected RBCs, for example, tend to become stiffer than their healthy counterparts. It is therefore desirable to design microfluidic devices which can detect diseases based on the cells'' deformability fingerprint, rather than preparing samples using expensive and time-consuming biochemical preparation steps. Our findings should be helpful in the development of new methods for sorting cells and particles by deformability.  相似文献   
952.
953.
The concept of 'modern education' is directly connected with Rousseau's theory of education. It is often said that Rousseau 'founded' modern education, or at least was its most influential predecessor. The paper argues that 'modern learning' or 'experimental education' was discussed within the late-17 th century 'quarrel of the ancients and moderns'. After this historically important debate, education and learning could be connected with the open experience of modern science. When compared to this tradition, Rousseau was not a modern writer. His concept of education has been far too paradoxical to serve as a groundwork for what was considered to be 'modern' or 'progressive education' at the end of the 19 th century. The image of progressive education was strengthened by child psychology, especially by theories of learning and development. Rousseau's stoic concept of 'negative education' is in many respects the opposite to such a viewpoint.  相似文献   
954.
Background: Inquiry-based science education (IBSE) is suitable to teach scientific contents as well as to foster scientific skills. Similar conclusions are drawn by studies with respect to scientific literacy, motivational aspects, vocabulary knowledge, conceptual understandings, critical thinking, and attitudes toward science. Nevertheless, IBSE is rarely adopted in schools. Often barriers for teachers account for this lack, with the result that even good teachers struggle to teach science as inquiry. More importantly, studies indicate that several barriers and constraints could be ascribed to problems teacher students have at the university stage.

Purpose: The purpose of this explorative investigation is to examine the problems teacher students have when teaching science through inquiry. In order to draw a holistic picture of these problems, we identified problems from three different points of view leading to the research question: What problems regarding IBSE do teacher students have from an objective, a subjective, and a self-reflective perspective?

Design &; method: Using video analysis and observation tools as well as qualitative content analysis and open questionnaires we identified problems from each perspective.

Results: The objectively stated problems comprise the lack of essential features of IBSE especially concerning ‘Supporting pupils’ own investigations’ and ‘Guiding analysis and conclusions.’ The subjectively perceived problems comprise concerns about ‘Teachers’ abilities’ and ‘Pupils’ abilities,’ ‘Differentiated instruction’ and institutional frame ‘Conditions’ while the self-reflectively noticed problems mainly comprise concerns about ‘Allowing inquiry,’ ‘Instructional Aspects,’ and ‘Pupils’ behavior.’

Conclusions: Each of the three different perspectives provides plenty of problems, partially overlapping, partially complementing one another, and partially revealing completely new problems. Consequently, teacher educators have to consider these three perspectives.  相似文献   
955.
956.
ABSTRACT

In this paper, the determinants of the intention to use online learning management system (LMS) among students in one of universities in the Kyrgyz Republic were studied, using quantitative and qualitative analysis. A total of 541 responses from students, enrolled in online courses during the fall and spring semesters 2016–2017, were used to examine students attitude toward online education. In addition, interviews with six instructors were conducted. Results showed that success of students in e-courses depend on year of education and the academic major of students. Factors, defined in the scope of this work, namely, technical characteristics of LMS, ease of use, feedback options of LMS and advantages of LMS use, were also found to be significant for students in their success in online courses. In interviews with instructors, three main points were highlighted, namely, problem with students’ perception of online courses, lack of online education experience among instructors and administrative issues.  相似文献   
957.
There is a common problem in artificial intelligence (AI) and information security. In AI, an expert system needs to be able to justify and explain a decision to the user. In information security, experts need to be able to explain to the public why a system is secure. In both cases, an important goal of explanation is to acquire or maintain the users’ trust. In this paper, I investigate the relation between explanation and trust in the context of computing science. This analysis draws on literature study and concept analysis, using elements from system theory as well as actor-network theory. I apply the conceptual framework to both AI and information security, and show the benefit of the framework for both fields by means of examples. The main focus is on expert systems (AI) and electronic voting systems (security). Finally, I discuss consequences of the analysis for ethics in terms of (un)informed consent and dissent, and the associated division of responsibilities.  相似文献   
958.
959.
Abstract

Acute infectious diseases are common in athletes and can impair their ability to train and to compete. Furthermore, continuing exercise during infectious diseases may lead to prolongation or aggravation of illness with severe acute or chronic organ manifestations. Therefore, even simple infectious diseases require a sufficient period of convalescence and recovery, during which exercise may be not allowed. Nowadays, especially in professional football with high pressures on players, staff and clubs due to broad public interests as well as financial constraints, the return-to-play decision is of utmost significance. Based on previous suggestions and our own experience within amateur and professional athletes and football players, this article aims to give a short overview on return-to-play decisions after common acute infectious diseases in football players.  相似文献   
960.
Following 602 Chinese twin pairs (48% male, all Han ethnicity) from primarily lower-than-average socioeconomic status families from early to mid-adolescence (Ms = 12 and 15 in 2006 and 2009), this study investigated gene–environment interplay between perceived parental supervision, peer drunkenness, and adolescent alcohol initiation. For alcohol initiation, shared environmental influences were initially negligible but became substantial. Genetic factors largely explained the links between both correlates with alcohol initiation. Parental supervision amplified genetic risks for alcohol initiation in early adolescence but suppressed it in mid-adolescence. Peer drunkenness augmented genetic and environmental influences at both times. Peer drunkenness showed stronger links and moderating potential than parental supervision. Chinese adolescents show dynamic gene–environment interplay patterns involving parent–child and peer processes in alcohol initiation.  相似文献   
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