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891.
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.892.
Objective: To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines. Methods: BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA; splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro. Results: The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone, but there was not significantly different (P>0.05). Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05). Conclusion: The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant. 相似文献
893.
Academic performance (i.e., grade point average) determines career entry factors as well as career success and is thus crucial for students’ future careers. Besides individual factors such as personality traits, individuals’ social embeddedness has been shown to enhance performance. Regarding academic performance, relationships to fellow students (peers), which bundle into one’s developmental network, are a valuable source of psychosocial and career support because occupying central positions within a social network provides the benefit of being able to access career-enhancing resources. Integrating individual and social-contextual factors for the purpose of examining academic performance is therefore plausible. Research results indicate that personality, especially extraversion, might predict performance through network centrality. In this study, we examined this assumption by focusing on extraversion and centrality in the peer developmental network of recently acquainted German psychology bachelor students (N?=?47, 15% male). In a longitudinal design, we analyzed the impact of extraversion and centrality on students’ academic performance at the end of their studies. Results revealed that centrality (i.e., popularity) mediates the relationship of extraversion with academic performance, indicating that extraverted students (regardless of their agreeableness) are more popular among their peers, which, in turn, enhances their academic performance. That is, the likelihood of getting superior final grades depends on whether students manage to attract peers at the very beginning of their university life, which is easier for extraverts. These findings emphasize the importance of the social embeddedness of people, highlight its long-term effects on performance, and yield several implications for research and practice. 相似文献
894.
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
895.
论健身性健美操的发展变化 总被引:1,自引:0,他引:1
健身性健美操是一项常学常新的项目,但科学、实用是最终的目的,新式健美操较旧式健美操在动作编排、上下肢动作分配、教学模式、教学侧重面、动作节奏、器械利用、音乐选择、运动科学化等八个方面发生了较大变化,有了新的创新与发展。 相似文献
896.
刘萍 《宁波大学学报(教育科学版)》2001,23(1):21-24
人们常对自己的成败进行归因。早在1976年,斯奈德等是学家就通过研究发现,人们倾向于将成功解释为自由身内在的一些因素所造成;而将失败归因于外部因素。即人们的归因受到自我价值保护的影响。本研究是通过问卷 形式对小学生的学业成绩进行归因,以期了解社会性发民菜并不成熟的未成年人是否也存在此种现象,并最终证明归因受到自我价值保护这种现象在小学中已产生了萌芽,其产生早晚与表现强弱和儿童的社会性发展密切相关。 相似文献
897.
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
898.
899.
结构性失业与高教政策调整 总被引:5,自引:0,他引:5
目前“知识失业”作为一共同难题正严重困绕着世界上几乎每一个国家。自1999年来,我国大学生就业率持续四年走低,引起社会各界的广泛关注,有人用“过度教育”理论来解释这一现象,然而,教育过度只是一种表象,实质是由于教育结构与经济结构之间的矛盾引起的结构性失业,调整高教政策以适应经济的发展在很大程度上能解决大学生就业问题。 相似文献
900.
浅议加强高职院校档案管理 总被引:6,自引:0,他引:6
加强档案管理对提升高职学院整体办学管理水平,为教育教学和学院的建设发展服务具有十分重要的意义。高职院校的档案管理存在一些不容忽视的问题,应从加强领导、提高人员素质,稳定队伍、实行现代化以及健全制度等方面进一步加强高职院校档案管理。 相似文献