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131.
Umran Betul Cebesoy Ceren Oztekin 《International Journal of Science and Mathematics Education》2018,16(7):1247-1268
Teachers have a crucial role to play in raising future generations of citizens who are aware of issues in genetics literacy such as gene therapy, cloning, and stem cell research. Teachers’ teaching practices are influenced by their knowledge in genetics literacy and their attitudes towards different issues. Accordingly, this study explored the relationships among middle school science teachers’ background characteristics (gender, teaching experience, self-perceived interest in and self-perceived knowledge of genetics), their genetics literacy levels, their attitudes towards various issues in genetics literacy, and their perceptions of teaching issues in genetics literacy. Data were collected from 435 Turkish middle school science teachers by completing the Genetics Literacy Assessment Inventory, the scale for attitudes towards issues in genetics literacy and perceptions of teaching issues in genetics literacy. The results of canonical correlation analysis suggested that being female, having a high level of interest in genetics, and perceiving oneself as knowledgeable in genetics were associated with higher levels of knowledge in genetics literacy and holding favorable general attitudes. These teachers believed in the necessity of introducing genetics literacy and held higher self-efficacy teaching beliefs regarding the teaching of issues in genetics literacy in their classes. However, they tended to emphasize more impeding factors as well as hold unfavorable attitudes towards gene therapy and gene therapy applications, implying that their attitudes were context dependent. 相似文献
132.
James Christopher Head 《Critical Studies in Education》2019,60(1):37-54
Following the trend of consequential accountability in US public education, New York City introduced a teacher evaluation program during the 2013–2014 school year that linked teachers’ individual performance ratings with their students’ exam scores. As this program systemically alters the nature of teacher–student relationships by transforming students into the means to an end (teachers’ professional viability), this study investigated the implementation of this accountability program from the point of view of the teachers – those who were the subject of this new policy. This study of 15 teachers’ narratives from 3 distinct schools illuminates a social-organizational process that I refer to as mediated institutional assault – a perceived attack on the teachers’ sense of personhood and moral agency perpetrated by mediating figures whose actions were facilitated by bureaucratic policies and institutionally coordinated tools of control. Thus, this study reveals that the consequence of this new mode of accountability is not merely the threat of losing one’s job, but also an insidious form of psychological assault, which in its masked delivery violates teachers’ sense of relational morality and challenges deeply engrained beliefs about their role as educators. 相似文献
133.
Peng-fei Qu Ya Zhang Jia-mei Li Ruo Zhang Jiao-mei Yang Fang-liang Lei Shan-shan Li Dan-meng Liu Shao-nong Dang Hong Yan 《Journal of Zhejiang University. Science. B》2018,19(1):71-78
Objective
This study investigated complementary feeding practices among four ethnic groups (Han, Uygur, Tibetan, and Zhuang) based on a cross-sectional survey in rural western China.Methods
In 2005, a stratified multistage cluster random sampling method was used to recruit 9712 children (7411 Han, 1032 Uygur, 678 Tibetan, and 591 Zhuang) between 6 and 35 months of age and their mothers from 45 counties in 10 provinces (autonomous regions, municipalities) in western China.Results
The rates of early introduction (before 6 months) of complementary foods in four ethnic groups (Han, Uygur, Tibetan, and Zhuang) were 71.30%, 95.95%, 82.40%, and 72.30%, respectively. The Infant and Child Feeding Index (ICFI) for Uygur and Tibetan children was lower than that for Han children at all age groups. Uygur children were more likely to have unqualified ICFI compared with Han children in a multivariate logistic regression (odds ratio (OR)=5.138, 95% confidence interval (CI): 4.340–6.084). A higher level of maternal education, greater family wealth, and the availability of complementary feeding educational materials decreased the likelihood of an unqualified ICFI. The nutritional status of children (Han, Tibetan, and Zhuang) with qualified ICFI was better than that for children with unqualified ICFI.Conclusions
Appropriate interventions are required to improve complementary feeding practices in rural western China.134.
Four pigeons responded on a two-component multiple token-reinforcement schedule, in which tokens were produced according to
a random-interval 30-sec schedule and exchanged according to a variable-ratio 4 schedule in both components. To assess the
effects of contingent token loss, tokens were removed after every second response (i.e., fixed-ratio 2 loss) in one of the
components. Response rates were selectively lower in the loss components relative to baseline (no-loss) conditions, as well
as to the within-condition no-loss components. Response rates were decreased to a greater degree in the presence of tokens
than in their absence. To control for the effects of changes in the density of token and food reinforcement, two parts consisted
of additional conditions where food density and token loss were yoked to those in a previous loss condition. In the yoked-food condition, tokens were produced as usual in both components, but the overall density of food reinforcement in one of the
components was yoked to that obtained during a previous token-loss condition. In the yoked token-loss condition, tokens were removed during one component of the multiple schedule at a rate that approximately matched the obtained
rate of loss from a previous token-loss condition. Response rates in these yoked components were less affected than those
in comparable loss components, despite similar densities of token, exchange, and food reinforcement. On the whole, the results
support the conclusion that contingent token loss serves as an effective punisher with pigeons. 相似文献
135.
卢东强 《上海大学学报(英文版)》2004,8(1):8-12
Based on the complex dispersion relation for the two-dimensional free-surface waves generated by a moving body in the steady Oseen flows, the effect of viscosity on wavelength and wave amplitude was investigated by means of an asymptotic method and a numerical analysis. A comparison between the asymptotic and numerical analysis for the viscous decay factor demonstrates the validity of the perturbation expansions for the wave profile. The numerical result shows that the wavelength of viscous wave is slightly elongated in comparison with that of inviscid wave. 相似文献
136.
This study investigated the effect of type of control and level of feedback during computer-based instruction. Subjects completed a computer lesson about the microscope that presented either mandatory or optional practice questions. Practice was accompanied by either elaboration feedback, correct-answer feedback, or no feedback. Results indicated that level of feedback had a significant effect on achievement and attitudes. Implications for including feedback in computer-based instruction are discussed. 相似文献
137.
Education in different communication media takes place with functional differences that have consequences for the course of instructional interaction. In this paper, we examine instructional interaction among people using a computer-based electronic message system, contrasting it with conventional face-to-face discussion in a college level class. Interaction via the non-real time message system contained multiple “threads of discourse,” a higher proportion of student turns to teacher turns, and other deviations from the “initiation-response-evaluation” sequences usually found in face-to-face classroom interactions. Based on the results of our contrast, we describe ways to organize instruction using electronic message systems to take advantage of new properties and to avoid shortcomings of these new instructional media. 相似文献
138.
Law enforcement officers, often the first professionals to come in contact with a victim of child sexual abuse, can either increase or decrease the traumatic impact on the child and the family at the time of disclosure. The model for a training program for police officers in handling cases of child sexual abuse outlined in this paper is divided into three sections. The first part is directed towards theoretical issues involved in this problem, including an explanation of the history and background of sexual abuse of children by adults and of the difference in the dynamics of extra- and intrafamilial sexual abuse. The second part consists of a detailed explanation of different types of sex offenses and of standard physical examinations of sexual abuse victims. Graded slides of physical trauma geared towards wound identification are paired with relaxation exercises. The third section focuses on special considerations when interviewing sexually abused children. The difference between interviewing and interrogation, specific questioning techniques, and the use of videotape is explained. Each part of this training procedure is followed by a question and answer period and small group discussions for the purpose of encouraging disclosure and better understanding of the officers' personal reactions to cases of child sexual abuse. 相似文献
139.
This study explores the reflective processes by which a grade 5 science community co-constructed shared inquiry structures to focus and guide its inquiry about human body systems over a school year supported by a collaborative online environment. The co-constructed structures included a list of collective wondering areas as the shared focus of inquiry and models of the inquiry process in the form of “research cycle.” Qualitative analyses of field notes, classroom videos, student notebooks and interviews elaborate the evolution of the inquiry areas and the “research cycle” model as well as students’ adaptive use of the structures to guide deeper inquiry. Content analyses of students’ individual research questions and collaborative online discourse indicate that students used the structures to develop more advanced inquiry and make productive contributions. The results contribute to elaborating a reflective structuration approach to co-organizing and sustaining long-term, open-ended inquiry in knowledge building communities. 相似文献
140.
The Occupational Information Network (O*NET) is the primary source of occupational information in the United States (US). In this study, I review O*NET’s usage for career guidance in India and conceive a career intervention based on it. In an empirical evaluation adopting a posttest-only experimental design with post-graduate management students (N = 220), effectiveness of the career intervention in reducing career decision-making difficulties is presented. An important cultural insight the study offers regarding occurrence of career decision-making difficulties, are the differences due to vertical–horizontal characteristics, apart from the more researched individualism–collectivism characteristics. 相似文献