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71.
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   
72.
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   
73.
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   
74.
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   
75.
A lecture is not necessarily a monologue, promoting only passive learning. If appropriate techniques are used, a lecture can stimulate active learning too. One such method is demonstration, which can engage learners' attention and increase the interaction between the lecturer and the learners. This article describes two simple and useful tools for demonstration during gross anatomy lectures. One is an apron for demonstrating midgut rotation and the other is a simple “human” model for demonstrating the relationship between the uterus and the peritoneum. Anat Sci Educ. © 2010 American Association of Anatomists.  相似文献   
76.
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   
77.
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   
78.
79.
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   
80.
This work deals with the problem of optimal residual generation for fault detection (FD) in linear discrete time-varying (LDTV) systems subject to uncertain observations. By introducing a generalized fault detection filter (FDF) with four parameter matrices as the residual generator, a novel FDF design scheme is formulated as two bi-objective optimization problems such that the sensitivity of residual to fault is enhanced and the robustness of residual to unknown input is simultaneously strengthened. A generalized operator based optimization approach is proposed to deduce solutions to the corresponding optimization problems in operator forms, where the related H/H or H?/H FD performance index is maximized. With the aid of the addressed methods, the connections among the derived solutions are explicitly announced. The parameter matrices of the FDF are analytically derived via solving simple matrix equations recursively. It is revealed that our proposed results establish an operator-based framework of optimal residual generation for some kinds of linear discrete-time systems. Illustrative examples are given to show the applicability and effectiveness of the proposed methods.  相似文献   
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