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21.
In this paper, we examine the role of reflection in teacher preparation, specifically within a mentoring relationship between cooperating and preservice teacher. We report findings from a case analysis of this pair who engaged in problem-posing dialogue within pre- and post-conferences around practice over one year of their work together in an elementary-level classroom. The context is an innovative programme in which cooperating teachers pursue their Master’s degree while undergraduates (preservice teachers) complete their elementary education degrees. Our analysis of talk about teaching during six coaching cycles as well as supporting documents illustrates how Jane’s mentoring supported reflective practices and disrupted a notion of a field experience as simply a place to ‘practice’ pedagogical knowledge with corrective feedback. Additionally, we explore the tensions in this approach to mentoring. This case study has implications for teacher educators who seek to bolster teacher preparation through the support of mentoring relationships.  相似文献   
22.
为了帮助设计者创建开放、灵活的分布式E-Learning环境,该文提出了一个E-Learning框架模型,从八个维度列出了E-Learning设计中需要考虑的关键问题:机构,教学,技术,界面设计,评价,管理,资源支持,伦理。  相似文献   
23.
The researchers conducted a grounded theory study to explore the experiences of Muslim American adolescents in high school. Findings indicate that students had to navigate unique challenges because of their religious faith, but those obstacles presented opportunities to confront bias and discrimination. Recommendations for how school counselors can support the development of Muslim American adolescents are presented.  相似文献   
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Clinical medical journals have not been effective in meeting the information needs of practitioners and bridging the gap between clinical research and practice. The slow adoption of results of clinical research is at least partly due to the failure of clinical journals to disseminate information in a way that would motivate practitioners to change practice. Although implementation is primarily a local process, medical journals are in a unique position to advance implementation by modifying their focus and adjusting their contents. Strategies that may be useful include publication of pre‐appraised evidence summaries and ‘clinical bottom‐lines’ and giving importance to systematic reviews and large evaluative research articles as they represent higher levels of evidence and have greater potential to change practice. Clinical journals should encourage researchers to consider how and by whom the findings will be used and provide information on implications for implementation such as possible strategies that may work, cost‐effectiveness, side‐effects and potential barriers to implementation. Medical journal publishers should explore ways to cooperate so that findings of landmark clinical trials could be shared thus reducing the ‘scatter’ of medical information. Electronic media offers numerous advantages such as quick accessibility and linking of information, and medical journals should capitalize on such innovations. There is a paradigm shift in health care practice as evidence is consciously and explicitly incorporated into individual patient care. Medical journals need to change to reflect this change in practice and provide practitioners with valid and relevant information.  相似文献   
26.
This study introduces a hybrid approach (i.e., a social network analysis technique and triple helix indicators) to study certain aspects of the e-government (EG) domain that would otherwise remain hidden when using conventional analytic tools. Particularly, we provide network analysis of the EG research domain by focusing on the network collaboration between regions, nations and institutions. We collected and analyzed 1091 scholarly papers which were classified as being about “e-government” by the Web of Science database. The results indicate that hybrid method can be used to understand certain network-level structures and patterns in the EG domain which are beyond the scope of the predominantly-used systematic literature review (SLR) method. Particularly, the hybrid method is useful in understanding collaboration patterns between countries, institutions and regions in the EG domain, identifying key players by studying their network properties (i.e., degree centralities); and in understanding the pattern of relations among universities, industries, and government. The implications of these results in terms of research and practice, and study limitations are discussed.  相似文献   
27.
Urinary iodine levels in children (5–11 years) and in adult males and females (15–44 years) of three ecological zones (hilly, flood-prone and plains) of Bangladesh were analyzed to determine the status of biochemical iodine deficiency in the country. Data indicated that a large majority of the population all over Bangladesh have biochemical iodine deficiency urinary iodine excretion (UIE) less than the accepted cut-off level of 10 μg/dl. Adults were deficient to comparable degrees, 31.3% severely iodine deficient. The flood-prone zone was less affected: 71.7% children had iodine deficiency and 25% were severely deficient. Adults of this zone were less affected than the children. Iodine deficiency was least severe in the plain zone: 59.8% children were biochemically iodine deficient and of them 23.4% had UIE less than 2.0 μg/dl. In the case of the adults of this zone, 60.8% were biochemically iodine deficient and 20.6% had severe iodine deficiency. The results indicate that Bangladesh as a whole is an iodine deficient region, with the hilly zone being the most severely affected. Children were slightly more affected than the adults, and females were more affected than the males.  相似文献   
28.
Mycorrhizoremediation an enhanced form of phytoremediation   总被引:2,自引:0,他引:2  
Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere mi- croflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial biotechnology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation.  相似文献   
29.
Goat ovaries were collected from the slaughterhouse and categorized as right, left, corpus luteum (CL)-present and -absent group and evaluated on the basis of weight (g), length (cm), width (cm), number of follicles, follicles aspirated and number and state ofcumulus-oocyte-complexes (COCs). Comparatively higher weight [(0.66±0.02) vs (0.64±0.02) g], length [(1.17±0.02) vs (1.1 ±0.02) cm] and width [(0.77±0.02) vs (0.74±0.02) cm] were found in right ovaries than those of left. On the other hand significantly (P〈0.05) higher weight [(0.71±0.03) vs (0.64±0.01) g] and width [(0.76±0.03) vs (0.75±0.01) cm] were found in CL-present group than those of CL-absent group of ovaries. The left ovaries contained comparatively higher number of normal COCs [(1.06±0.09) per ovary] than fight ovaries [(1.03±0.10) per ovary] and the similar trend was found in total number of follicles [(4.51±0.25) vs (4.30±0.23) per ovary] and follicles aspirated [(2.55±0.14) vs (2.52±0.12) per ovary]. But the total COCs per ovary was almost similar in both ovaries [right and left: (1.85±0.12) and (1.85±0.11) per ovary, respectively]. Higher number of total COCs [(1.87±0.09) vs (1.76±0.16) per ovary], total number of follicles [(4.45±0.19) vs (4.16±0.37) per ovary], follicles aspirated [(2.55±0.10) vs (2.48±0.21) per ovary] and normal COCs [(1.12±0.07) vs (0.76±0.14) per ovary] were found in CL-absent group than those of CL-present group of ovaries.  相似文献   
30.
In this paper, the issue of output voltage regulation in buck type dc-dc converters is addressed using a current sensorless control technique. The proposed strategy integrates a finite time current observer with an adaptive backstepping control scheme to yield a cost-effective and robust control mechanism. The overall controller stability in the sense of Lyapunov is proved. Applicability of the proposed control is verified experimentally on a buck converter in the laboratory. The control scheme is implemented on dSPACE DS1103 platform based on DSP TM320F240 processor. To examine the efficacy of the proposed method, the buck converter is subjected to a wide change in input voltage, load resistance and reference voltage. For comparison purpose, a conventional adaptive backstepping control scheme is evaluated under identical conditions of experimental study to examine the merit of the proposed control. The results obtained reveal that the proposed control is prompt in rejecting perturbations and achieves a smooth, reliable and satisfactory output voltage regulation with faithful and time bound estimation of inductor current. Thereby, this investigation demonstrates the validity of the proposed control in maintaining a stringent output voltage regulation in buck converters.  相似文献   
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