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21.
Drug discovery is an expensive and lengthy process. Among the different phases, drug discovery and preclinical trials play an important role as only 5–10 of all drugs that begin preclinical tests proceed to clinical trials. Indeed, current high-throughput screening technologies are very expensive, as they are unable to dispense small liquid volumes in an accurate and quick way. Moreover, despite being simple and fast, drug screening assays are usually performed under static conditions, thus failing to recapitulate tissue-specific architecture and biomechanical cues present in vivo even in the case of 3D models. On the contrary, microfluidics might offer a more rapid and cost-effective alternative. Although considered incompatible with high-throughput systems for years, technological advancements have demonstrated how this gap is rapidly reducing. In this Review, we want to further outline the role of microfluidics in high-throughput drug screening applications by looking at the multiple strategies for cell seeding, compartmentalization, continuous flow, stimuli administration (e.g., drug gradients or shear stresses), and single-cell analyses.  相似文献   
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Elena Aronova 《Minerva》2012,50(3):307-337
The Congress for Cultural Freedom is remembered as a paramount example of the “cultural cold wars.” In this paper, I discuss the ways in which this powerful transnational organization sought to promote “science studies” as a distinct – and politically relevant – area of expertise, and part of the CCF broader agenda to offer a renewed framework for liberalism. By means of its Study Groups, international conferences and its periodicals, such as Minerva, the Congress developed into an influential forum for examining the ways Big Science impacted the relations between science, society, and politics, thus constituting a semi-institutional niche for Science Studies before its professionalization within academia during the 1970s. I argue that the Congress contributed to the construction of public space in which the relations between science, society and politics were debated, and science was reconceptualized as a social activity. The vision of “science studies” the CCF-associated intellectuals promulgated was different from the science studies we know today. Yet, this alternative vision, in which the issues of science politics appeared inseparable from those of science policy, science organization, and science governance, constituted the “pre-history” of science studies today.  相似文献   
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The purpose of this study was twofold: to examine how attitudinal and instructional variables differentiated 4th-grade students in Cyprus, Hong Kong, and the USA; and to determine how those variables were related to math performance on the TIMSS test. A discriminant analysis was performed to examine how those variables differentiated the students in the 3 countries. The most striking result was that the students from all 3 countries, who were similar to the average students in Cyprus, had the highest achievement within their countries. Thus, 4th-grade students who liked math, who thought it was important to do well in math for their friends, who did not need private instruction, and who had not been taught using computers or small group procedures, tended to be the better students. However, students who were similar to the average USA student had the lowest achievement within each of the 3 countries.  相似文献   
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The paper aims to further explore the role that culture plays in the provision and assimilation of sex education among Latina immigrants in the USA. To accomplish this, researchers conducted focus groups and interviews with 30 women from Central and South America who have lived in the USA for at least five years. Participants were asked to reflect on their experience with sex education in their home country and in the USA, and to assess how their attitudes towards sex education may impact their behavioural choices as parents and as sexually-active women. The findings demonstrate a wide range of views that did not follow patterns by common demographical proxy variables, suggesting that such variables are not enough to predict adoption of new cultural values that are different from their family's traditional norms. Instead, adherence to traditional cultural beliefs appeared to be a better predictor of attitudes and behaviours.  相似文献   
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3D printing technology is a powerful educational tool that can promote integrative STEM education by connecting engineering, technology, and applications of science concepts. Yet, research on the integration of 3D printing technology in formal educational contexts is extremely limited. This study engaged preservice elementary teachers (N?=?42) in a 3D Printing Science Project that modeled a science experiment in the elementary classroom on why things float or sink using 3D printed boats. The goal was to explore how collaborative 3D printing inquiry-based learning experiences affected preservice teachers’ science teaching self-efficacy beliefs, anxiety toward teaching science, interest in science, perceived competence in K-3 technology and engineering science standards, and science content knowledge. The 3D printing project intervention significantly decreased participants’ science teaching anxiety and improved their science teaching efficacy, science interest, and perceived competence in K-3 technological and engineering design science standards. Moreover, an analysis of students’ project reflections and boat designs provided an insight into their collaborative 3D modeling design experiences. The study makes a contribution to the scarce body of knowledge on how teacher preparation programs can utilize 3D printing technology as a means of preparing prospective teachers to implement the recently adopted engineering and technology standards in K-12 science education.  相似文献   
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Educational Studies in Mathematics - The competency-based approach conceives mathematics as a necessary tool for dealing with daily-life tasks. Many studies have focused on examining the low math...  相似文献   
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We propose the use of ISI-JCR categories as units of cocitation and measurement for the construction of heliocentric maps. The use of a spatial metaphor allows us to illustrate, analyze and compare domains in terms of the categories and their interconnections or links. We can also move around within the structure of these domains for further analysis, and access the documents associated to the categories and to the links that cocite or relate them.  相似文献   
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In this paper, we have developed a classification model for online learning environments that relates the Instructors Overall Performance (IOP) rating (according to students’ perceptions) with the course characteristics, students’ demographics and the effectiveness of the instructor in his/her teaching roles. To that end, a comprehensive Student Evaluation of Teaching (SET) instrument is proposed, which includes not only conventional teaching elements, but also items that encourage twenty-first century skills. The goal of the study is twofold: (i) to quantify the extent to which the selected variables explain the IOP rating, and (ii) determine which teaching and non-teaching variables most affect the IOP rating. The best performing classifier achieved a competitive accuracy, highlighting that the selected variables mainly determine the IOP values. Other important findings include: (i) the IOP value is mainly influenced by the effectiveness of the instructor in his/her teaching roles; (ii) teaching strategies that involve the cooperation between the technical and pedagogical roles should be promoted; (iii) the pedagogical role has the highest impact on the final IOP value; and (iv) the most influential demographic variable is the student’s status (working commitments and family responsibilities).  相似文献   
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