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The Government has set targets for an expansion in student numbers by the year 2,000 at a time when there is a dramatic fall in the numbers of school leavers. Institutions of higher education need to create new markets for student recruitment, both among mature people and also among 18 year-olds, this latter implying a more realistic assessment of the ability of applicants to benefit from courses and a new approach to school leaving examinations. In order to maximise the exploitation of these markets, institutions must adopt a more serious attitude to admissions, treating them more as matters of policy rather than of administrative function. Unless higher education adopts aggressive marketing and selling practices it will lose out to employers in the competition for young people.  相似文献   
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The study described in this article was designed to gather information about teachers' perspectives on achievement testing and to describe where the competency-based testing in Continuous Uniform Evaluation Systems (CUES) programs fits into teachers' overall plans for teaching and assessing students.The specific objectives of the research were (1) to develop a taxonomy of techniques that teachers use to assess students, (2) to describe teachers' uses and perceptions of various assessment techniques, and (3) to describe the implementation of various assessment activities in natural classroom settings. The results of the study have implications for the design and implementation of instructional systems in school settings.  相似文献   
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In response to Shady’s reflection on his experience as a teacher-researcher in which he explored different cogen structures, we consider fluid participant configurations using cogens as a research method to provide insights into classroom life. Our cogens illuminated the role of symbolic, cultural and social capital in student–teacher alignments that changed across different classroom situations. In Shady’s study, as well as our own, respectful student–teacher relationships that involved the teacher and students first establishing common social capital, enabled the teacher to “be in with” the students, and vice versa. We raise questions about how the structure of cogens might affect the nature of the dialogue that is cogenerated.  相似文献   
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Cryopreservation of human red blood cells (RBCs) in the presence of 40% glycerol allows a shelf-life of 10 years, as opposed to only 6 weeks for refrigerated RBCs. Nonetheless, cryopreserved blood is rarely used in clinical therapy, in part because of the requirement for a time-consuming (∼1 h) post-thaw wash process to remove glycerol before the product can be used for transfusion. The current deglycerolization process involves a series of saline washes in an automated centrifuge, which gradually removes glycerol from the cells in order to prevent osmotic damage. We recently demonstrated that glycerol can be extracted in as little as 3 min without excessive osmotic damage if the composition of the extracellular solution is precisely controlled. Here, we explore the potential for carrying out rapid glycerol extraction using a membrane-based microfluidic device, with the ultimate goal of enabling inline washing of cryopreserved blood. To assist in experimental design and device optimization, we developed a mass transfer model that allows prediction of glycerol removal, as well as the resulting cell volume changes. Experimental measurements of solution composition and hemolysis at the device outlet are in reasonable agreement with model predictions, and our results demonstrate that it is possible to reduce the glycerol concentration by more than 50% in a single device without excessive hemolysis. Based on these promising results, we present a design for a multistage process that is predicted to safely remove glycerol from cryopreserved blood in less than 3 min.  相似文献   
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