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81.
It is difficult to motivate learners to seek out and persist at challenging learning tasks where failure is likely. However, in game environments, people seem highly motivated to engage with challenges and respond productively to failure. Many typical game features purportedly enhance intrinsic motivation and self-efficacy, which should improve students’ reactions to challenge and failure, which should in turn enhance learning. An experimental study with early middle school students tested these assumptions by comparing a “Full” version of a typical, commercial programming game to a “Minimal” version of the same game where common game features such as narrative, performance metrics, high-quality graphics, and sound were removed. In contrast to our hypotheses, players of the Full Game were less likely to choose coding challenges, were less tolerant of coding failures and gained less coding knowledge. Intrinsic motivation and self-efficacy did not differ between conditions. Correlational analyses showed that failure tolerance and challenge seeking may critically affect learning from educational games. The current study offers an existence proof that some common game features can hinder players' failure tolerance, challenge-seeking and learning, in certain game contexts. Future research should isolate the effects of individual game features, test generalizability and explore which contextual variables influence the findings.  相似文献   
82.
We have undertaken a critical appraisal of the current English system of law regulating: (1) Provision of services designed to prevent children coming into care of local authorities, which are the authorised agencies for dealing with children who are abused or neglected. (2) Ways of receiving children into care and also ways of terminating care orders. We question whether, and under what circumstances, care orders are really necessary. (3) Periodic reviews of children in care. We are critical of the English system and look to models in the USA as guides towards the possible reform of English law. We take the same perspective when considering termination of parental rights. In our opinion good laws do not of themselves provide the care and love which a child requires, but they make the caring possible by loved and loving adults. We argue that the law must provide the best possible framework to allow adequate caring by members of the non-legal professions, such as social workers and foster parents. At the same time the law must ensure that the rights of parents and children are protected.  相似文献   
83.
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data...  相似文献   
84.
Willmott GR  Platt M  Lee GU 《Biomicrofluidics》2012,6(1):14103-1410315
Tunable pores (TPs) have been used for resistive pulse sensing of 1 μm superparamagnetic beads, both dispersed and within a magnetic field. Upon application of this field, magnetic supraparticle structures (SPSs) were observed. Onset of aggregation was most effectively indicated by an increase in the mean event magnitude, with data collected using an automated thresholding method. Simulations enabled discrimination between resistive pulses caused by dimers and individual particles. Distinct but time-correlated peaks were often observed, suggesting that SPSs became separated in pressure-driven flow focused at the pore constriction. The distinct properties of magnetophoretic and pressure-driven transport mechanisms can explain variations in the event rate when particles move through an asymmetric pore in either direction, with or without a magnetic field applied. Use of TPs for resistive pulse sensing holds potential for efficient, versatile analysis and measurement of nano- and microparticles, while magnetic beads and particle aggregation play important roles in many prospective biosensing applications.  相似文献   
85.
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   
86.
国产十种乌头的染色体研究   总被引:1,自引:0,他引:1  
本文描述了我国产毛茛科乌头属的10个种的染色体数目和形态。  根据该属染色体基 数为8(x=8),可将这些种归为二倍体、四倍体、六倍体和八倍体种。  10种乌头的染色体在数目、大小、结构上表现出相关性。其中具根状茎而多年生的种多为二倍体,染色体形态较大,第3-7号多为近端着丝点(st)染色体, 具块茎而二年生的种多为多倍体,染色体形态较小,第3-7号多为近中着丝点(sm)染色体。染色体演化方向可能是二倍体→多倍体、大→ 小、st→sm。这进一步证明根状茎种较块茎种原始。根据染色体数目和形态,又可将这些种的染色体分为两类。这进一步支持了目前分类学上的牛扁亚属和乌头亚属的划分。本文还讨论了这些种的有关分类问题。  相似文献   
87.
Concurrent droplet charging and sorting by electrostatic actuation   总被引:1,自引:0,他引:1  
This paper presents a droplet-based microfluidic device for concurrent droplet charging and sorting by electrostatic actuation. Water-in-oil droplets can be charged on generation by synchronized electrostatic actuation. Then, simultaneously, the precharged droplets can be electrostatically steered into any designated laminar streamline, thus they can be sorted into one of multiple sorting channels one by one in a controlled fashion. In this paper, we studied the size dependence of the water droplets under various relative flow rates of water and oil. We demonstrated the concurrent charging and sorting of up to 600 droplets∕s by synchronized electrostatic actuation. Finally, we investigated optimized voltages for stable droplet charging and sorting. This is an essential enabling technology for fast, robust, and multiplexed sorting of microdroplets, and for the droplet-based microfluidic systems.  相似文献   
88.
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   
89.
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   
90.
This paper distils 24 years of classroom research into promoting quality learning in science classrooms to develop an overall framework for better understanding and describing both the learning and the teaching approaches that stimulate and support it. For me, quality learning is characterised by adjectives such as informed, purposeful, reflective, intellectually active, metacognitive and independent. Central to quality learning is the role of talk, and central to promoting talk which promotes quality learning are certain teacher behaviours. I first focus on the ways that teachers behave in the classroom in order to promote, react to and use student talk. These behaviours are summed up in a list of twelve principles for quality teaching. Each of these principles requires, as well as appropriate teacher behaviours, the use of effective teaching procedures. I then focus on four kinds of student talk that exemplify informed, purposeful, reflective and intellectually active thinking. These variously involve students’ existing ideas and explanations; increasing student ownership of practical activities; constructive challenges to the teacher (or text’s) idea, and lateral, reflective ‘thinking’ questions.  相似文献   
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