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31.
When time-intensive longitudinal data are used to study daily-life dynamics of psychological constructs (e.g., well-being) within persons over time (e.g., by means of experience sampling methodology), the measurement model (MM)—indicating which constructs are measured by which items—can be affected by time- or situation-specific artifacts (e.g., response styles and altered item interpretation). If not captured, these changes might lead to invalid inferences about the constructs. Existing methodology can only test for a priori hypotheses on MM changes, which are often absent or incomplete. Therefore, we present the exploratory method “latent Markov factor analysis” (LMFA), wherein a latent Markov chain captures MM changes by clustering observations per subject into a few states. Specifically, each state gathers validly comparable observations, and state-specific factor analyses reveal what the MMs look like. LMFA performs well in recovering parameters under a wide range of simulated conditions, and its empirical value is illustrated with an example.  相似文献   
32.
Ordinary and thermal diffusion of moisture in activated alumina are investigated using a new diffusion cell design and scheme of analysis reported earlier. The specific form of the mass flux equation has a pronounced effect on the magnitude of the associated thermal diffusion ratio. In the case of activated alumina-moist air, if a partial pressure gradient is used, then the thermal diffusion term is small if not zero.Free, Knudsen and surface diffusion all play a part in the diffusion through activated alumina. However, surface diffusion makes the major contribution and for this reason the model in this case can be simplified to a two parameter surface model.The activation energy for surface diffusion is constant and is approximately equal to the mean isosteric heat of absorption. In addition, mean pore radius, turtuosity, and other physical constants are computed from the least square fit of experimental data. Furthermore, the model is theoretically consistent over the entire concentration range (0≦ CACAsat).A new fact about activated alumina (Grade F1) it that it does not transfer moisture in a nonisothermal condition so long as the partial pressures of moisture on the two sides of the pellet are the same. There appears to be no previous report of this fact in the periodical literature.  相似文献   
33.
Lee K  Kim C  Young Yang J  Lee H  Ahn B  Xu L  Yoon Kang J  Oh KW 《Biomicrofluidics》2012,6(1):14114-141147
We propose a simple method for forming massive and uniform three-dimensional (3-D) cell spheroids in a multi-level structured microfluidic device by gravitational force. The concept of orienting the device vertically has allowed spheroid formation, long-term perfusion, and retrieval of the cultured spheroids by user-friendly standard pipetting. We have successfully formed, perfused, and retrieved uniform, size-controllable, well-conditioned spheroids of human embryonic kidney 293 cells (HEK 293) in the gravity-oriented microfluidic device. We expect the proposed method will be a useful tool to study in-vitro 3-D cell models for the proliferation, differentiation, and metabolism of embryoid bodies or tumours.  相似文献   
34.
For the last 70 years, since the establishment of the Republic of Korea, Korean education has achieved universal expansion of educational opportunity from elementary to secondary to higher education. Planning, centralized policy making, top-down implementation, and administrative control had been the standards of the first few decades of Korean education. The so-called May 31 education reform implemented in 1995 made a turning point for these approaches to education policy and administration by highlighting autonomy, openness, diversity, accountability, consumer centeredness, market control, and governance for quality education. However, these government-driven education reform initiatives have resulted in limiting the expected outcomes. In this paper, the authors call for a new approach to education policy and administration and propose supporting school innovation, empowering an internal accountability system in governance. The authors also suggest a search for normative values for democratic communitarianism as a new philosophical foundation of education policy framework, beyond instrumental values of education.  相似文献   
35.
Abstract

Over the last decade, school-based professional learning communities (PLCs) have emerged as a key feature of the education system in South Korea. To understand this relatively new phenomenon in the context of South Korea, we provide a review of research on school-based PLCs in South Korea and an empirical analysis of the Teaching and Learning International Survey (TALIS) 2008 with a focus on school-based PLCs. Based on our findings from the literature review and analysis of the TALIS, we aim to provide a fuller picture of the emerging landscape of school-based PLCs in South Korean schools. In so doing, we focus on what constitutes school-based PLCs in South Korean schools and how they are similar to and/or different from their counterparts in other countries. Implications for policy, practice, and research are discussed.  相似文献   
36.
ABSTRACT

Scholars focus on the social nature of academic writing to refine an understanding of feedback interactions in higher education. However, studies on the various sources of feedback – feedback networks – have been scarce, particularly during the initial years of doctoral education. Using a qualitative case study approach, multiple sources of feedback for four students in one doctoral program in the United States were identified in line with broader trends focusing on feedback as a social practice. Informed by the academic socialization framework [Duff, Patricia A. 2012. “Second Language Socialization.” In Handbook of Language Socialization, edited by Alessandro Duranti, Elinor Ochs, and Bambi B. Schieffelin, 564–586. Malden: Wiley-Blackwell], this study aims (1) to navigate the landscape of graduate feedback, including interactions beyond class as well as oral and written feedback, and (2) to elucidate the socialization process. Findings suggest that academic writing development is defined as how feedback is situated within disciplinary, academic communities of interaction. This article describes how the larger network of feedback creates the types of interaction that characterizes the community.  相似文献   
37.
This research explored how between-group collaboration enhanced the co-construction of knowledge and performance on project-based learning tasks of collaborative learning groups. The findings of 2 case studies, one that focused on between-group mentoring and one that focused on between-group project review, revealed that both strategies were perceived favorably by the students and had a positive impact on the collaborative learning skills, the knowledge revealed through their online dialogue, and the project performance of all students, especially the less effective groups. The results provide some insights into the computer-supported collaborative learning process among students in a higher education context.  相似文献   
38.
The discourse around development is full of buzzwords, including gender and a myriad of variants that underscore the importance of development policies addressing gender imbalances. Despite their prevalence in development policy and research, terminology related to gender is often used broadly, inappropriately, and without nuance. For international education policy in particular, discussions related to gender equality and equity in education are engaged in such a way that assumes shared meanings between policy designers and policy recipients. Using Kenya as a site of analysis, and in the spirit of a vertical case study for data collection, this study explores how the abstractness of a buzzword functions in the microcosm of the school classroom. In comparing gendered representations in textbooks with students' perceptions of those representations to explore how development discourse plays out in Kenyan schools, findings here demonstrate that there is minimal impact due to textbooks' mixed messages, reinforcing women's marginal position in community and political engagement and demonstrating that broad-based understandings of gender empowerment are not always translated in application.  相似文献   
39.
40.
The aims of this experiment were to determine whether there are differences between the sexes in the three-dimensional angular rotations of the lumbo-pelvic-hip complex during running and, if such differences exist, to establish whether factors other than sex can explain the observed differences. A cohort of 44 non-injured runners (22 males, 22 females) who usually ran more than 20 km per week were voluntarily recruited. All trials were conducted on a treadmill at a running speed of 4.0 m x s(-1). Reflective markers were placed over specific anatomical landmarks of the thoraco-lumbar spine, pelvis and femur. Data were captured using a VICON motion analysis system. Females tended to display a greater peak-to-peak oscillation for most of the angular rotations. An offset was the main difference between the male and female group mean waveforms for pelvis anterior-posterior tilt. Forward stepwise regression analysis revealed that sex was the most common variable related to the amplitudes of the angular rotations. Given these results, sport scientists conducting future biomechanical studies using angular data to test hypotheses are advised to be extremely cautious about averaging across male and female participants.  相似文献   
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