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81.
82.
Herbert H. Severson Marianne Pickett Deborah J. Hetrick 《Psychology in the schools》1985,22(2):179-186
One hundred eighty-one experienced teachers (elementary and junior high), and 189 preservice teachers were surveyed regarding their perceptions of school psychologists. The survey instrument used essentially the same categories as Styles in 1965, including: (a) level of training, (b) effectiveness, (c) qualifications for tasks, and (d) usefulness in specific duties. Analysis of the survey data showed there were significant differences between preservice and experienced teachers' effectiveness ratings of school psychologists on eight tasks typically performed by school psychologists. Significant differences also were found between preservice and experienced teachers on their ratings of school psychologists' qualifications to undertake specific tasks, although almost half of the experienced teachers were unable to rate the effectiveness of school psychologists. There was a small, but significant, negative relationship between the amount of contact with the school psychologist and the perceived effectiveness. Limitations inherent in survey methodology and the need to foster greater teacher awareness of the school psychologist's role are discussed. 相似文献
83.
The premise that underlies the preservice‐teacher‐education programme at Monash University is the need to focus on the nature of learning (for example, Gunstone et al., 1993). One approach currently being used to enhance this process is the use of portfolios. The portfolio is an open‐ended task designed to explore teaching from many different vantage points. It is organised as a dynamic assessment task through which the student teachers work on developing their understanding of what it means to be a science teacher, and the teaching portfolio itself is a mixture of artefacts designed to help student teachers demonstrate this to others. This paper reports on the effectiveness and value of portfolios in helping preservice teachers learn about learning and teaching. 相似文献
84.
Catherine C. Chase Laura J. Malkiewich Alison Lee Stefan Slater Ahram Choi Chenmu Xing 《British journal of educational technology : journal of the Council for Educational Technology》2021,52(1):57-74
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
85.
Elisabeth M. Spratto Brian C. Leventhal Deborah L. Bandalos 《Educational and psychological measurement》2021,81(1):39
In this study, we examined the results and interpretations produced from two different IRTree models—one using paths consisting of only dichotomous decisions, and one using paths consisting of both dichotomous and polytomous decisions. We used data from two versions of an impulsivity measure. In the first version, all the response options had labels; in the second version, only the endpoints were labeled. Based on past research, we hypothesized that the endpoints would be selected more frequently in the endpoint-only labeled condition, and the midpoint response option would be selected more frequently in the fully labeled condition. Results from the two models (dichotomous and polytomous) were similar and indicated that our hypotheses were partially supported—specifically, there was no consistent pattern in terms of which condition saw a higher frequency of midpoint response selection. However, our hypotheses regarding extreme responding in the endpoint-only labeling condition were supported. 相似文献
86.
Yuen Mantak Chung Y. B. Lee Queenie A. Y. Lau Patrick S. Y. Chan Raymond M. C. Gysbers Norman C. Shea Peter M. K. 《International Journal for Educational and Vocational Guidance》2020,20(3):653-676
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
87.
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
88.
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
89.
90.
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