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101.

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.
  相似文献   
102.
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   
103.
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   
104.
Conclusions Although we do not understand very well what the processes are that contribute to language development, it is clear that communication plays a central role. As children strive to become increasingly skilled at communicating their ideas (White, 1959), as they have increasingly complex ideas to communicate (Piaget, 1955), and as they encounter an increasingly diverse set of people with whom to communicate (Brown, 1973), they must learn to use language which is richer and more flexible.When children come to school or to a day care center they already know a great deal about language. They have readily and actively mastered words, sentences and forms of communication which they need in their own family and community. In their new environment—the school or center—children's language development can further be fostered by adults who are receptive to children's efforts at communication. Adults who encourage children to use language in new ways, who attend to what children mean to say and who recognize that children's errors are often not mistakes, are likely to play a positive role in children's language development.Janet H. Kane and Karen Sheingold are on the Staff at Bank Street College of Education.  相似文献   
105.
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   
106.
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   
107.
There has been increasing recognition for the need to reform doctoral training practices to foster students’ personal epistemology. This study describes the design and evaluation of a learning experience designed to help students understand the scholarly publication process. Firstly, this study discusses the design of the learning experience, describing the collaborative process of writing an interdisciplinary publication using both online and face-to-face learning. Secondly, this study evaluates the effectiveness of the learning experience by examining students’ reflections. We show that participation in the learning experience helped students to develop their academic writing proficiency, collaboration and teamwork, intercultural competence, and ability to engage in reflective practice. Importantly, we show that each student also created more individualised knowledge, gaining insight into how they and others think. This study, therefore, demonstrates that personal epistemology can be fostered through collaboration in a doctoral writing group context.  相似文献   
108.
In der Entscheidung Morgan und Bucher hat der Europäische Gerichtshof zwei Regelungen des deutschen Bundesausbildungsförderungsgesetzes zur Ausbildungsförderung für Auslandsstudien als gegen die Freizügigkeit der Unionsbürger nach Art 18 EGV verstoßend und somit gemeinschaftsrechtswidrig angesehen. Das Urteil unterstreicht die Bedeutung, die der Gerichtshof der Freizügigkeit und der Gleichbehandlung von Unionsbürgern im Bildungsbereich zuerkennt. Dies wird von Österreich auch bei Klärung der Hochschulzugangsproblematik zu berücksichtigen sein. Das durch eine Novelle zum österreichischen Studienförderungsgesetz eingeführte Mobilitätsstipendium ist entsprechend den vom Europäischen Gerichtshof in Morgan und Bucher entwickelten Grundsätzen am Gemeinschaftsrecht zu messen.  相似文献   
109.
Using national survey data and discrete-time logit modeling, this research seeks to understand whether student aid mediates the relationship between parental income and student dropout behavior. Our analysis confirms that there is a gap in dropout rates for low-income students compared with their upper income peers, and suggests that some types of aid are associated with lower risks of dropout. Thus, we examine the interaction between financial aid type and parental income to explore whether, and if so how, different types of aid may reduce the dropout gap by income level group. We find that the receipt of a Pell grant is related to narrowing the dropout gap between students from low- and middle-income groups, although overall the interaction between Pell grant and income is not significant. Loans and work-study aid both have similar effects on student dropout across all income groups. Methodologically, our results demonstrate the need to model dropout behavior temporally and to avoid main-effect bias by incorporating interaction effects.
Stephen L. DesJardinsEmail:
  相似文献   
110.
This study analysis the relationship between perceptions of the justice of teacher’ behaviour and (a) the legitimation of school authority and (b) the legitimation of institutional authorities outside school. 448 adolescent students participated in the study. In questionnaire participants were asked about (a) perceptions of the justice of teachers’ behaviour; (b) evaluation of the school experience; and (c) evaluation of institutional authorities. Results show that the evaluation of the justice of teacher behaviour, in particular relational and procedural justice, have an impact on the legitimation of the authority of teachers and on the evaluation of institutional authorities outside school. Results also show that the legitimacy granted to teachers is a mediator variable between perceptions of justice in school and evaluation of authorities outside school. These results are discussed in the context of the studies on the relationship between school experience and adolescents attitudes towards authorities, and in the framework of the “Relational Model of Authority” and of the “Group Value Model”.  相似文献   
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