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91.
In this paper, thermal mixing characteristics of two miscible fluids in a T-shaped microchannel are investigated theoretically, experimentally, and numerically. Thermal mixing processes in a T-shaped microchannel are divided into two zones, consisting of a T-junction and a mixing channel. An analytical two-dimensional model was first built to describe the heat transfer processes in the mixing channel. In the experiments, de-ionized water was employed as the working fluid. Laser induced fluorescence method was used to measure the fluid temperature field in the microchannel. Different combinations of flow rate ratios were studied to investigate the thermal mixing characteristics in the microchannel. At the T-junction, thermal diffusion is found to be dominant in this area due to the striation in the temperature contours. In the mixing channel, heat transfer processes are found to be controlled by thermal diffusion and convection. Measured temperature profiles at the T-junction and mixing channel are compared with analytical model and numerical simulation, respectively. 相似文献
92.
Xue Wang Yuetong Wang Zhaoyuan Fang Hua Wang Jian Zhang Longfu Zhang Hsinyi Huang Zhonglin Jiang Yujuan Jin Xiangkun Han Shenda Hou Bin Zhou Feilong Meng Luonan Chen Kwok-Kin Wong Jinfeng Liu Zhiqi Zhang Xin Zhang Haiquan Chen Yihua Sun Liang Hu Hongbin Ji 《国家科学评论(英文版)》2021,8(10)
Somatic mutations of the chromatin remodeling gene ARID2 are observed in ∼7% of human lung adenocarcinomas (LUADs). However, the role of ARID2 in the pathogenesis of LUADs remains largely unknown. Here we find that ARID2 expression is decreased during the malignant progression of both human and mice LUADs. Using two KrasG12D-based genetically engineered murine models, we demonstrate that ARID2 knockout significantly promotes lung cancer malignant progression and shortens overall survival. Consistently, ARID2 knockdown significantly promotes cell proliferation in human and mice lung cancer cells. Through integrative analyses of ChIP-Seq and RNA-Seq data, we find that Hspa1a is up-regulated by Arid2 loss. Knockdown of Hspa1a specifically inhibits malignant progression of Arid2-deficient but not Arid2-wt lung cancers in both cell lines as well as animal models. Treatment with an HSPA1A inhibitor could significantly inhibit the malignant progression of lung cancer with ARID2 deficiency. Together, our findings establish ARID2 as an important tumor suppressor in LUADs with novel mechanistic insights, and further identify HSPA1A as a potential therapeutic target in ARID2-deficient LUADs. 相似文献
93.
Three hundred and seven teacher education students of a Hong Kong university were administered two questionnaires, one measuring emotional autonomy (EAS) and the other measuring perceived parenting styles (PAQ) of their parents. It was found that the Hong Kong teacher education students tended to be autonomous and they characterized their parents as authoritative instead of authoritarian. In addition, the emotional autonomy scale was positively related to authoritarianism, but negatively related to authoritativeness and permissiveness of parenting. Emotional detachment instead of autonomy seemed to be a more appropriate meaning of EAS for the interpretation of results. Implications were drawn for future research including development of an improved instrument in measuring emotional autonomy to study its associations with perceived parenting styles of young people across cultures. 相似文献
94.
In the last two decades, China's education has experienced significant transformations and restructuring on account of privatization and marketization. Unlike the Mao era when the state assumed the major responsibilities in financing and providing education, individuals and families have now to bear increasing financial burdens in paying for education. The marketization and privatization of education has undoubtedly intensified educational inequalities and widened regional disparities between the economically developed areas in the eastern coast and the less economically developed areas in the middle and north-western parts of the country. The growing inequalities in education and the increasing financial burdens presented by education have been a source of social discontentment, which have in turn prompted the central government to revisit its approaches to educational development. This article sets out to examine, how in this wider policy context, China's education has been transformed following the adoption of more pro-competition and market-oriented reform measures. This article is based on intensive secondary data analysis, fieldwork observations, and findings from a household survey conducted in eight different Chinese cities about people's perceived education hardship. The article concludes by considering how the Chinese government has attempted to address the problems of educational inequalities that have intensified on account of two decades of education marketization. 相似文献
95.
Peter A. Creed Oi Yin Wong Michelle Hood 《International Journal for Educational and Vocational Guidance》2009,9(3):189-203
The study tested the relationship between occupational aspirations/expectations (type and status) and decision-making difficulties,
efficacy and career barriers in 498 Chinese high school students. Males aspired to investigative and enterprising types, but
expected realistic and enterprising ones; females aspired to enterprising and conventional types, but expected conventional
and social ones. Students with aspirations/expectations type discrepancies were more likely to be higher achieving females;
those with aspirations/expectations status discrepancies had poorer academic achievement, less confidence and perceived more
barriers. 相似文献
96.
Abstract: The current generation of students coming into food science and engineering programs is very visually oriented from their early experiences. To increase their interest in learning, new and visually appealing teaching materials need to be developed. Two diverse groups of students may be identified based on their math skills. Food science students tend to find it difficult to use mathematics as a problem‐solving tool for food engineering problems. Food engineering students, on the other hand, should be challenged to use emerging mathematical tools to develop their problem‐solving skills. Therefore, the approach of this project involved the development of a curriculum to train undergraduate food engineers in the effective use of computational fluid dynamics (CFD) software to solve food engineering problems by engaging them in the creation of food engineering teaching tools. These CFD outputs were then used as innovative teaching tools for the food science students. In this paper, this concept will be illustrated by unsteady‐state heat transfer and fluid flow problems. To evaluate the efficiency of the teaching materials developed, a student focus group was asked to answer the same quiz following a conventional and CFD output aided teaching session. The assessment result showed an improved understanding of the subject after the CFD teaching session. These visual aids were excellent tools to illustrate the validity of the formulas presented in class. In addition, the new visual materials enabled a better understanding of the relationships among different process parameters. In general, this helped the food science students better appreciate the food engineering concepts that govern food processing operations. 相似文献
97.
6世纪中国佛教忏仪流行甚广,以张荣迁碑和陈海龙碑为代表的造像碑就是最好的例证。考察发现,二碑所刻佛名分别来自《金光明经》、《法华经》和《大通方广忏悔灭罪庄严成佛经》。此文在铭文考释的基础上探讨了佛名与忏仪的关系。 相似文献
98.
99.
Yu Ka Wong 《Reading and writing》2018,31(4):945-964
This study explored the concurrent and longitudinal relationships between reading and writing in young Chinese-as-a-second-language (CSL) learners’ sentence writing, using structural equation modeling. The participants comprised 126 Hong Kong senior primary ethnic minority students, whose literacy skills were assessed at two time points over the course of a year. In grade 5 (Time-1), they were assessed with Chinese character reading and reading comprehension measures to evaluate their reading ability. In grade 6 (Time-2), their sentence reading, sentence writing, and literacy component skills of Chinese character writing fluency and written syntactic skills were assessed. The results demonstrated that students’ reading and writing performances were substantially related both concurrently and longitudinally. Furthermore, (1) at Time-2, the component skills accounted for substantial portions of variance in sentence reading and writing skills, along with the relationship between them, while (2) Time-1 reading ability predicted Time-2 component skills and, through the mediation thereof, indirectly predicted sentence writing. Thus, in light of the linguistic characteristics of the Chinese language, literacy component skills are crucial component processes that connect reading and writing in CSL learners’ sentence writing. 相似文献
100.
Tiantian Kong Jun Wu Kelvin Wai Kwok Yeung Michael Kai Tsun To �� Liqiu Wang 《Biomicrofluidics》2013,7(4)
We report a facile and robust microfluidic method to fabricate polymeric core-shell microspheres as delivery vehicles for biomedical applications. The characteristics of core-shell microspheres can be precisely and easily tuned by manipulating the microfluidic double emulsion templates. The addition of a shell can significantly improve the versatility as well as functionality of these microspheres as delivery vehicles. We demonstrate that the nature of the shell material plays an important role in the properties of the core-shell delivery vehicles. The release kinetics is significantly influenced by the material of the shell and other characteristics such as the thickness. For example, by adding a poly(lactic-co-glycolic acid) (PLGA) shell to an alginate core, the encapsulation efficiency is enhanced and undesired leakage of hydrophilic actives is prevented. By contrast, adding an alginate shell to PLGA core can lead to a reduction of the initial release rate, thus extending the release period of hydrophobic actives. Microfluidic fabrication enables the generation of precisely controlled core-shell microspheres with a narrow size distribution, which enables the investigation of the relationship between the release kinetics of these microspheres and their characteristics. The approach of using core-shell particles as delivery vehicles creates new opportunities to customize the release kinetics of active ingredients. 相似文献