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991.
Student interaction in school contexts is a topic that has been researched from many different perspectives. However, the role of students as tutors scaffolding other peers is not normally addressed, since studies are usually focused on the teacher. Moreover, considering the many technologies that can support students’ work nowadays, studies describing specific practices are still needed in order to understand the many possibilities and constraints that can emerge from the use of these tools in the field of education. This exploratory case study aims to extend research on scaffolding between students, presenting data from an ethnographic study where a commercial video game was introduced as part of the curricular activities. Analytically, the scaffolding metaphor is the departing point to describe in detail how the scaffolding process took place, focusing on its purposes and on the role of students as tutors. Our findings reveal how students offered mostly procedural scaffoldings, performing tutor functions such as highlighting relevant features, reducing levels of freedom or controlling the frustration. Results highlight that students can perform scaffolds, and this should be considered as part of the classroom design, making this process visible. Moreover, specific features of the video game enhanced these interactions, which should also be considered when designing game learning environments in the future.  相似文献   
992.
Through the analysis of survey and interview data, we investigated the attitudes and perceptions of 32 multilingual teachers of Spanish in Belize, a code-switching (CS) context where Spanish is in intense contact with English and Belizean Kriol. More specifically, we examined teachers’ and students’ attitudes toward Spanish and CS and teachers’ perceptions vis-à-vis students’ attitudes toward Spanish instruction. The study revealed that whereas some teachers held negative views of Northern Belizean Spanish, they did not markedly perceive standard Spanish as “better” than the local variety of Belizean Spanish. The analysis also showed that most teachers had a positive predisposition to the use of CS as a pedagogical tool in their classrooms, a finding that suggests that ultra-normative attitudes toward Spanish varieties are not prevalent among these educators. In view of students’ attitudes, teachers concurred that students had overwhelmingly negative attitudes toward standard Spanish, in line with previous findings. We argue that educational reforms and status-planning efforts are vital to destigmatize Spanish and to promote its maintenance alongside Belizean Kriol and English.  相似文献   
993.
The objective of this study was to develop and validate an instrument to assess the attitude of student pharmacists toward prayer in general and in particular as it relates to their academic performance. To fulfill the study objective, faculty from seven colleges of pharmacy located at Christian universities collaboratively developed the Student Prayer Attitude Scale (SPAS). The items were used to assess the attitudes of student pharmacists toward prayer as well as the effects of prayer on personal lives and academic performance. Faculty investigators asked 1,563 students to complete the survey and received 677 valid responses. A principal components analysis with promax rotation was conducted and revealed a two-factor structure: (a) general attitude toward prayer and (b) specific attitude regarding the impact of prayer on academic performance. Analysis of variance was used to compare student responses by religious identity. Students identifying as atheist or agnostic were significantly different in their responses than students from theistic religions; however, the responses of students from various theistic religions were not significantly different from one another. Faculty concluded that SPAS is a reliable tool for measuring student attitudes toward prayer. The use of such a tool could help faculty tailor educational opportunities to allow pharmacy students to explore prayer more fully and be aware of its impact on the patients they serve.  相似文献   
994.
Research points to significant numbers of students on college campuses experiencing mental health distress and an ever increasing number of college students who are choosing to make an off-campus educational experience a part of their college careers. When we consider both of these trends together, it is quite apparent that a significant number of students with mental health concerns will spend periods of time studying away from campus, with converging concerns among college mental health and study away professionals about how to best support these students. This article seeks to outline both challenges and opportunities inherent in the collaboration between campus professionals in supporting students with mental health issues before and during their study away experiences.  相似文献   
995.
996.
Focusing on digital text messages containing information about students’ absences and sent to parents by schools, the paper investigates the way school absenteeism is produced within affective assemblages. The paper unfolds a theoretical and methodological approach of ‘going with’ the text messages, in entanglements of affective flows. The empirical engagements, produced together with multiple agents in two Swedish schools, show that within the assemblages of human and nonhuman bodies, the text messages can become ‘stirrers’ that evoke nervousness and anxiety, but also excitement and feelings of control that affect the production and conception of absenteeism. The affective flows of text messages thus travel in all directions, with and against notions of linearity. The conclusion emphasizes how the text messages, as affective materialities, are an inextricable part of the production of school absenteeism in multiple and sometimes unexpected ways.  相似文献   
997.
998.
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   
999.
The primary objective for modeling of machining processes is to develop a predictive capability of machining performance in order to facilitate effective planning of machining operations. This capability leads to faster implementation, higher performance, quality at a lower cost. This comes about due to improved selection of machining parameters, optimal fixture design and the avoidance of tool failure. The simulation system presented simultaneously considers the effect of cutter geometry, the cutter's initial position errors, workpiece geometry, machine tool dynamics, and workpiece/fixture system dynamics on the machining process.The integration of all of the above in one model provides an off-line tool to simulate and optimize the machining parameters and the fixture configuration cutting both lead and production time. The modular nature of the simulation system presented allows for the study of many different machining processes. The cutting forces in this system are modeled using a mechanistic approach. NURBS curves and surfaces are utilized for the geometric modeling and simulation of the machining process. While a finite element method is used to model and analyze the workpiece/fixture dynamics. Two case studies are presented to demonstrate the practical application of the presented simulation. The first case presents the optimization of the fixture configuration of a generic automotive component. While the second case presents the results of simulations performed on a novel mill/grind machining process. This process is a combination of face milling and grinding in one operation. Some simulated results are presented along with experimental validation.  相似文献   
1000.
To study the protective role of Arogh on isoproterenol induced myocardial damage in rats. The effect of Arogh pretreatment on isoproterenol induced myocardial damage was assessed by studying the levels of lipid peroxides and changes in the activity of marker enzymes such as creatine kinase, lactate dehydrogenase and transaminases in serum and heart tissue. In isoproterenol administered rats, a significant decrease was observed in the activity of marker enzymes in the heart with a corresponding increase in their levels in serum. Lipid peroxide levels increased significantly in the serum and heart. In rats pretreated with arogh, the level of lipid peroxides and the activity of marker enzymes were maintained at near normal values. Pretreatment with Arogh offered a protective effect against isoproterenol induced myocardial damage in rats as evidenced by LDH isoenzyme patterm and histopathological studies of heart tissue.  相似文献   
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