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961.
This paper draws on an empirical work dedicated to discussing a theoretical model for design-based research. The context of our study is a research project for the design, the implementation and the analysis of Insectophagia, a digital role-play game implemented in secondary schools. The model presented in this paper aims at conceptualizing researchers’ and practitioners’ relationships with the notion that knowledge development takes place at a meta-didactical level when the participants develop a shared practice and a shared discourse on practice (a common praxeology). This is done through collaboration and teacher-centered design of innovative learning settings. This model emerges from a double approach: (1) a literature review on collaborative research in education and, (2) an analysis of the verbal interactions of practitioners and researchers involved in the project. The study emphasizes the development of knowledge among participants. It also emphasizes the importance of knowledge brokering for filling the gap between research and practice and thus, for the adoption of digital technology by practitioners.  相似文献   
962.
Curriculum development is particularly challenging in computing-related disciplines as the computing industry changes more quickly than most. As information technology degrees have become relatively pervasive, some institutions that offer information systems degrees have recognized a need to develop specialist studies in information systems. This detailed case study shows the forces related to a successful implementation of new Health Informatics degrees. The case describes both an unsuccessful and then a successful attempt at essentially the same curriculum development. Although the case includes some local political factors, these represent typical considerations that a curriculum developer is likely to encounter.  相似文献   
963.
Teacher loss due to migration is a global phenomenon that impacts both developed and developing nations the world over. The aim of this study was to find out about the career plans of final-year South African student teachers. A group of final-year Bachelor of Education student teachers from a South African university responded to a questionnaire on intra- and intercontinental migration. The responses were analysed quantitatively and/or qualitatively. The findings showed that 79% of the students indicated that they would be teaching in South Africa, 8% were planning to teach in another country, while 8% were undecided. More than a third of the students (38%) said that they would like to teach in another country in five years’ time. Just more than a quarter of the students (27%) preferred Australia as a destination country. The student teachers’ most important motive to teach in a foreign country was the opportunity to travel, followed by earning a higher salary, and professional development. The student teachers indicated that their most important migration needs before leaving South Africa were information about health care, accommodation, and banking assistance.  相似文献   
964.
Efficient lysis is critical when analyzing single cells in microfluidic droplets, but existing methods utilize detergents that can interfere with the assays to be performed. We demonstrate robust cell lysis without the use of detergents or other chemicals. In our method, cells are exposed to electric field immediately before encapsulation in droplets, resulting in cell lysis. We characterize lysis efficiency as a function of control parameters and demonstrate compatibility with enzymatic assays by measuring the catalysis of β-glucosidase, an important cellulase used in the conversion of biomass to biofuel. Our method enables assays in microfluidic droplets that are incompatible with detergents.  相似文献   
965.
Abstract

This article develops a conceptual model of users’ and designers’ knowledge roles in the information and communication technology design process. The “ideal” center at the intersection of the axes for division of knowledge work and privileging of knowledges represents a balanced distribution of knowledge work between users and designers and an avoidance of privileging either group over the other. The article then applies this model to analyses of the design process for six video games wherein the knowledges of Indigenous peoples in North America were mobilized. It concludes by discussing implications for research and design practice, particularly for broadening the participation and self-articulation of marginalized groups.  相似文献   
966.
The oxidative modification of lipoprotein especially low density lipoprotein (LDL) plays a key role in the initiation and progression of atherosclerosis. Serum apolipoproteinB (apoB) level is found to be an important marker for atherosclerosis. The present paper focuses on the measurement of serum apoB levels and the effect of Vitamin E, Vitamin C and reduced glutathione on the copper ion induced oxidation of LDL + VLDL (VLDL-Very Low Density Lipoprotein) lipoprotein fraction isolated from the serum of chronic renal failure (CRF) and renal transplanted patients. The level of apoB is significantly higher in the serum of transplanted patients when compared to CRF patients and normal subjects. The level of TBARS formed in oxidized LDL + VLDL lipoprotein fraction of CRF and renal transplanted patients are significantly increased than normal even in the presence of antioxidants but the level of TBARS produced, with antioxidants is comparatively lesser than that produced by oxidized lipoprotein fraction without antioxidants. It may be concluded than that produced by oxidized lipoprotein fraction without antioxidants. It may be concluded that oxidation of LDL can be prevented at an earlier stage by Vitamin E supplementation. The supplementation with Glutathione serves as the best method of preventing the lipoprotein oxidation among the renal diseased patients.  相似文献   
967.
968.
Benson KR 《Endeavour》2000,24(2):59-62
The modern discipline of biology was formed in the 20th century from roots deep in the natural-history tradition, which dates from Aristotle. Not surprisingly, therefore, ecology can also be traced to natural history, especially its 19th-century tradition emphasizing the adaptive nature of organisms to their environment. During the 20th century, ecology has developed and matured from pioneering work on successional stages to mathematically rich work on ecosystem energetics. By the end of the century, ecology has made a return to its natural-history heritage, emphasizing the importance of the integrity of ecosystems in considering human interactions with the environment.  相似文献   
969.
Indian ethnicity by itself is a strong risk factor for development of CAD in Indian postmenopausal women due to lower HDL levels as compared to Whites and women of oriental origin. We evaluated and compared the short-term effects of menopause, estrogen replacement therapy and combined estrogen and progestin replacement therapy on various atherogenic indices. 40 postmenopausal women, both surgical and natural (20 each) were selected. 10 surgical postmenopausal women were given 0.625 mg conjugated estrogens daily for 6 months and 10 natural postmenopausal women were given 0.625 mg conjugated estrogen with 2.5 mg medroxyprogesterone acetate daily. 20 women were included in the control group and given placebo. Fasting venous blood samples were analyzed for extended lipid profile and calculated atherogenic indices before starting the therapy and after 1,3 and 6 months. LDL and Apolipoprotein B increased (p<0.05) and those of Apolipoprotein A1 and HDL decreased in the control groups. In both the study groups levels of serum cholesterol and LDL decreased (p<0.05) and those of HDL and Apolipoprotein A1 increased (p<0.01). LDL/HDL, Apo B/ApoA1, Total Cholesterol/HDL decreased significantly (p<0.05) in both the study groups compared to the control groups. The effect of estrogen alone was more significant as compared to combination therapy. Log Triglycerides (TG)/HDL ratio showed a decrease in women on estrogen alone but the difference was not significant. Our study confirms that short term HRT has a favorable effect on atherogenic indices in Indian postmenopausal women.  相似文献   
970.
During the period 1952 to 1965, there were strenuous world-wide efforts to produce an automated cotton spinning mill. These attempts, which involved the use of concepts developed outside the textile machinery industry (i.e. automatic transfer systems), were motivated by the need to reduce the very great amount of manual handling of packages between successive operations in the yarn manufacturing process.The case is unusual in that, while many of the developments were ‘technically successful’ in that installations were made which functioned satisfactorily in the mill), they were, without exception, commercially unsuccessful from the point of view of the machinery manufacturer and mill operator. This paper describes the economic forces which led to the attempts at automation, and explains why, after an expenditure in excess of £ 25 mill/on worldwide, commercial success was not achieved.The prime reason for failure lay in minor and major developments of existing individual machines, which had continued independently of automation research, and which had, to a great extent, obviated the economic need for automation. The surprising thing (in retrospect at least), is that, as production rates were increased step by step, development engineers working to produce automated systems saw, in the increasing speeds, only a challenge to their ingenuity — not a disappearance of the need for automatic transfer devices.A secondary reason for failure in the particular case of the Shirley Institute's automated card room sequence lay in the fact that the research was directed by a committee whose terms of reference were limited to pursuance of a defined goal — the development of an automated card room. The committee had no mandate to question the soundness of its objectives, and the work continued until a technically successful system was finally produced.  相似文献   
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