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981.
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   
982.
传统的音乐审美观因过于强调音乐内容与形式的一致性,一味承袭“严肃音乐”的教育教学程式,导致了音乐审美价值研究视角狭窄,陷入了误区。本文力求通过音乐价值与音乐审美之间、音乐文化价值与音乐审美价值之间关系的分析与探讨,从而揭示音乐审美价值的内涵及其实现的基本途径。  相似文献   
983.
由于经济和环境因素,现阶段对高速、高精度、高效机床的需求越来越迫切,电主轴作为数控机床的关键功能部件,国内外学者在电主轴结构设计及测控技术方面做了大量的研究,取得了较好的研究成果。主要从国内外电主轴的结构创新、优化设计提高电主轴综合性能及电主轴的测量技术进行介绍,从中了解电主轴的研究现状,为我国电主轴设计人员及学者提供参考。  相似文献   
984.
Xu  Lei  Li  Yonghong  Zhu  Jiang  Liu  Zhiyuan 《天津大学学报(英文版)》2019,25(4):312-321
The adsorption performance of toluene on ultra-stable Y zeolite(USY) was studied via dynamic adsorption. The effects of bed temperature, initial concentration, and feed flow rate on adsorption were investigated. The Yoon–Nelson model was used to fit the toluene breakthrough curves. The length of mass transfer zone was calculated based on breakthrough curves. The Langmuir–Freundlich model fit the adsorption isotherms of toluene on USY, which indicated that the surface of USY was heterogeneous. The adsorption isosteric heat calculated from adsorption isotherms ranged from 54.3 to 69.8 kJ/mol, indicating physical adsorption. The combined technique of temperature swing adsorption with vacuum swing adsorption(TVSA) exhibited excellent desorption performance, which was attributed to the low desorption activation energy. Under optimized TVSA conditions, the desorption rate of toluene reached 90.6% within 10 min. The long-term cyclic utilization results indicated that the adsorption capacity of USY was stable.  相似文献   
985.
高校网络德育评估是高校网络德育的重要组成部分.高校网络德育评估必须遵循层次性评估与整体性评估相结合、短期效果评估与中长期效果评估相结合等构建原则,依据评估程序,运用主观性定性、面向对象等评估方法,以促进高校网络德育的实效性.  相似文献   
986.

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   
987.
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   
988.
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   
989.
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   
990.
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   
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