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Computers on wheels: an alternative to 'each one has one'   总被引:1,自引:0,他引:1  
Four fifth‐grade classrooms embarked on a modified ubiquitous computing initiative in the fall of 2003. Two 15‐computer wireless laptop carts were shared among the four classrooms in an effort to integrate technology across the curriculum and affect change in student learning and teacher pedagogy. This initiative—in contrast to other one‐to‐one programmemess and stationary labs—offers public schools alternatives to budget constraints and instructional‐space overhead. Results indicate positive teacher technology competence and confidence, as well as instructional strategies that were student‐centred made meaningful uses of technology. Teacher technological knowledge and efficacy, pedagogical knowledge, and a supportive school community seem to be strong indicators for impacting technology integration in this context.  相似文献   
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The aim of this study was to evaluate newly developed performance feedback tools from the student perspective. The tools were innovative in both their mode of delivery and the range of stakeholders they involved in the feedback process. By using the tools in health and social care settings, students were able to engage in interprofessional assessment of common competences and obtain performance feedback from a range of stakeholders not commonly involved in work-based learning; these included peers and service users. This paper discusses the ways in which the performance feedback tools were developed by a collaborative programme and compares their delivery, across a wide range of professions and work-based settings, in paper-based, web-based and mobile formats. The tools were evaluated through a series of profession-specific focus groups involving 85 students and 7 professions. The data were analysed thematically and reduced to three key categories: mode of delivery, assessment tool dynamics and work-based issues. These will be discussed in detail. The students agreed that the structured way of capturing and documenting feedback from several sources would support their practice placement learning. The reflective nature of the tools and the capacity for guiding reflection was also welcomed. The concepts of gaining service user, peer and/or interprofessional feedback on performance were new to some professions and evoked questions of reliability and validity, alongside appreciation of the value they added to the assessment process.  相似文献   
997.
This paper evaluates a unified theory for HIV/AIDS counselling. The evaluation was based upon the hypothesis that if the theory was valid it would generate therapeutic outcomes. The theory was operationalised and evaluated in the context of group counselling. The group counselling sessions were video recorded and the tapes were viewed by a research team. Details of the counselling were recorded through the process of triangulation. The therapeutic outcomes were stated and confirmed with the group members through the process of respondent validation. In conclusion the hypothesis was accepted and the unified theory does offer an appropriate foundation upon which HIV/AIDS counselling can be based.  相似文献   
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Pancreatic fibrosis is a key pathological feature in the etiology of chronic pancreatitis that leads to obliteration of exocrine and endocrine pancreatic tissues and its replacement by fibrous tissue resulting in clinical manifestations. Matrix metalloproteinase 9 is a member of the MMP family that is also known as gelatinase B, degrades type IV collagen of extracellular matrix and basal membrane. The present study is aimed at evaluating the clinical significance of plasma concentration of MMP-9 in chronic pancreatitis. The samples were obtained from 112 chronic pancreatitis patients and an equal number of age and sex matched healthy controls. MMP-9 levels were quantitatively measured by ELISA assay. Statistical analysis was applied to test the significance of results. The present study revealed a significant increase of plasma MMP 9 levels in chronic pancreatitis patients compared to control subjects. Elevated levels were also observed in all the patient groups compared to control subjects with regard to sex, age, addictions etc. MMP-9 degrades the type IV collagens in normal basement membrane, which in turn activates the pancreatic stellate cells which promote the development of pancreatitic fibrosis. Thus, elevated plasma levels of MMP-9 may act as a susceptibility factor for the development of chronic pancreatitis.  相似文献   
999.
The classification of journal titles into fields or specialties is a problem of practical importance in library and information science. An algorithm is described which accomplishes such a classification using the single-link clustering technique and a novel application of the method of bibliographic coupling. The novelty consists in the use of two-step bibliographic coupling linkages, rather than the usual one-step linkages. This modification of the similarity measure leads to a marked improvement in the performance of single-link clustering in the formation of field or specialty clusters of journals. Results of an experiment using this algorithm are reported which grouped 890 journals into 168 clusters. This scope is an improvement of nearly an order of magnitude over previous journal clustering experiments. The results are evaluated by comparison with an independently derived manual classification of the same journal set. The generally good agreement indicates that this method of journal clustering will have significant practical utility for journal classification.  相似文献   
1000.
All optical network (AON) is a hot topic in recentstudies of optical fiber communications . Key tech-niques in AONinclude optical switching/routing,opti-cal cross connection ( OXC) , all optical wavelengthconversion (AOWC) ,all optical buffering,etc. Opti…  相似文献   
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