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901.
Eric Sanchez Réjane Monod-Ansaldi Caroline Vincent Sina Safadi-Katouzian 《Education and Information Technologies》2017,22(6):2805-2824
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
902.
Kevin R. Parker Sankara Subramanian Srinivasan Robert F. Houghton Nima Kordzadeh Karoly Bozan Thomas Ottaway Bill Davey 《Education and Information Technologies》2017,22(4):1497-1513
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
903.
904.
905.
J. J. R. de Villiers 《Africa Education Review》2017,14(3-4):212-229
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
906.
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
907.
J. B. Varuna Kumara N. R. Ravikumara Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2016,31(4):390-401
Folic acid is used for preventing and treating multiple diseases and disorders, administered in the form of oral supplements. The present research work was aimed to study the influence of two non-ionic surfactants Poloxamer and Tween 80 (Polysorbate 80) on pectin submicrospheres formulations. Typical natural polymer pectin was used to encapsulate folic acid by cross linking method. The resultant submicrospheres contributed to improve the aqueous solubility to enhance the bioavailability of folic acid. During investigation, it was observed that pectin polymers influenced kinetics of the rate of reaction more intensively than the surfactants. The physical phenomenon caused the change in their size, shape and chemistry of pectin polymers transforming into submicrospheres in aqueous condition. The characteristic differences of submicrospheres were assessed by scanning electron microscopy, differential scanning calorimetry and Fourier-transform infrared spectroscopy. The average diameters of the submicrospheres ranged between 250 and 500 nm. The encapsulation efficiency of submicrospheres ranged between 80 and 96 %. The characteristic swelling behavior of lyophilized submicrospheres was influenced by the ratio of pectin polymers and folic acid used in the formulations. The submicrospheres systems exhibited controlled release of folic acid due to the pH-dependent solubility of pectin polymers in aqueous medium. The submicrospheres showed good haemocompatibility suggesting them to be promising candidates for oral delivery. 相似文献
908.
AbstractThis 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
909.
910.
C. S. Parameswari B. Vijayageetha R. Vijayakumar 《Indian journal of clinical biochemistry : IJCB》2006,21(1):131-136
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