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91.
The purpose of the study was to examine preservice teachers’ attitudes using Second Life for multicultural literacy and to explore effective strategies to implement this technology in teacher preparation programs. Participants included thirty-six preserve teachers from early childhood, elementary, and secondary education programs. Participants indicated that interacting with cultural artifacts and diverse populations promoted multiculturalism, 47.5% reported that Second Life supported the development of multicultural attitudes and 50% indicated that Second Life can support multicultural respect. Additionally, 33.4% considered Second Life an effective learning tool for K-12 education while 40% remained undecided. Participants questioned the veracity of certain objects, often failed to communicate with individuals from other cultures, and worried about inappropriate content. Despite these limitations, Second Life could serve as a rich environment to build multicultural knowledge through culturally representative locations, artifacts, and communication. Suggestions for incorporating multicultural experiences via Second Life are presented. 相似文献
92.
93.
Ibrahim Kocabas 《Journal of The Franklin Institute》2011,348(7):1339-1362
The Laplace transformation technique has been widely applied to modeling of tracer transport in oil and geothermal reservoirs, and in groundwater aquifers. However, mathematical models of many flow and transport problems could only be obtained as Laplace space solutions, and hence, their computations had to involve a numerical inversion technique.In this work, we employ the iterated Laplace transformation technique to develop novel closed form solutions to the tracer transport models in heterogeneous media. Two types of configurations have been considered: tracer transport in single fracture located in low-permeability matrix and tracer transport in a double porosity medium consisting of flowing and dead-end pore systems. In addition, both linear and radial flow geometries have been considered for both configurations. Applications of iterated Laplace transform technique to these four types of models are presented as fundamental examples and their numerical results were used as benchmarking for the numerical inversion results from Stehfest and Dubner and Abate algorithms.As the technique is quite versatile, we expect that the method should gain widespread acceptance to develop solutions to a wide range of problems in flow and transport in porous media and improve the application of nonlinear regression technique to these solutions.This work has achieved four important objectives: first, two novel Laplace transform relations that are useful in tracer studies are presented. Second, the present work serves to verify/invalidate the results of numerical inversion algorithms. In addition, it provides better insight into tracer transport mechanisms. Finally, it serves as a powerful tool of design and interpretation of tracer tests. All four objectives are illustrated in this work. 相似文献
94.
95.
Ibrahim Dahlstrom‐Hakki Jodi Asbell‐Clarke Elizabeth Rowe 《Mind, Brain, and Education》2019,13(1):30-40
The value of neurocognitive measures to study memory, attention, cognition, and learning is well established. However, the vast majority of work using these tools is performed in tightly controlled lab experiments using simple lab stimuli. This article looks at the viability of using multimodal neurocognitive instruments to measure implicit knowledge in real‐world learning contexts. We focus on some of the most promising neurocognitive tools for this purpose, including eye‐tracking, electroencephalography (EEG), and functional near infra‐red spectroscopy (fNIRS). The specific challenges and potential of each tool are considered for use within learning contexts. These tools may be of particular importance to student populations that typically underperform on traditional learning assessments, including students with disabilities, English language learners, and students from low socioeconomic status backgrounds, among others. This review concludes with recommendations to the field for further work required to bring objective measures of implicit knowledge to real world learning contexts. 相似文献
96.
The paper deals with the optimal control of a distributed host structure consisting of two elastically connected complex continuous double-string system and subjected to certain excitation load. Investigation of the behavior of such system is of great theoretical and practical importance. A technique is proposed to actively damp out the undesired vibrations in the structures by a combination of applied actuators and displacement feedback gains. Two performance measures, involving energies at the terminal time as well as applied and feedback control efforts, are introduced. The optimality conditions of the applied actuators are derived by using the method of eigenfunction expansion and calculus of variations. The feedback parameters are numerically determined from the solution of a minimization problem. The proposed approach is illustrated by a numerical example involving a system which consists of two strings subjected to a continuous load. 相似文献
97.
Mohamed Ahmed Abdelmoaty M. A. Ibrahim N. S. Ahmed M. A. Abdelaziz 《Indian journal of clinical biochemistry : IJCB》2010,25(2):188-192
Quercetin (QE), one of natural flavanoid group, was widely distributed as a secondary metabolite in plant kingdom. It has
been believed that oxidative stress plays a role in the pathogenesis of diabetes mellitus (DM). The aim of the present study
was the evaluation of possible effects of QE on blood glucose and antioxidant enzymes in experimental streptozotocin (STZ)-induced
diabetes in rats. STZ was injected intraperitoneally with single dose of 50 mg/kg for diabetes induction. QE (15 mg/kg bw
day, intraperitoneal (i.p.) injection) was injected for 3 days prior to STZ administration; these injections were continued
to the end of the study (for 25 days). Glucose tolerance test and random plasma glucose were done for all animals. Cellular
antioxidant enzymes such as glutathione peroxidase (GSHPx), superoxide dismutase (SOD) and catalase (CAT) activities were
measured in pancreatic homogenates. Quercetin had no effect on plasma glucose level of normal animals but its pre- treatment
was able to prevent diabetes induced by single intraperitoneal injection of streptozocintreated rats. Antioxidant enzyme activity
significantly decreased in STZ induced diabetic group. QE treatment significantly increased the antioxidant enzyme activities.
It could be concluded that quercetin, a flavonoid with antioxidant properties, exerting its beneficial antidiabetic effects. 相似文献
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99.
Ibrahim Bayazit 《International Journal of Science and Mathematics Education》2013,11(3):651-682
This study examines new Turkish elementary school mathematics textbooks to provide perspectives on the quality of the tasks related to the proportion concept and the ways they are presented. Tasks were analysed for several dimensions with a particular focus on their level of cognitive demands (LCD). Tasks were distinguished in two groups in terms of LCD: lower-level demand and higher-level demand. The findings revealed that 75 % of the tasks were related to higher-level demand in that they requested a certain level of interpretation, required connecting knowledge and procedures related to each other, demanded responses with some explanation and reinforced students’ non-algorithmic thinking. Only 25 % of the tasks were related to a lower-level demand, and these tasks could be resolved by recalling and implementing rules, procedures and factual knowledge without reflecting upon the meaning behind them. Most of the tasks were presented in multiple representations and framed in non-mathematical contexts. All these task characteristics indicate that the new elementary school textbooks have the capacity to promote students’ proportional reasoning. The findings also inform the international community about crucial aspects of the curriculum reforms in Turkey and provide suggestions for teachers and textbook writers concerning the quality of the tasks and their selection and implementation in the classrooms. 相似文献
100.
Explanation studies underlined the importance of using evidence in support of claims. However, few studies have focused on students' use of others' data (second-hand data) in this process. In this study, students collected data from a local water source and then took all the data back to the classroom to create scientific explanations by using claim–evidence–reasoning model on a new mobile application. A middle school science teacher from a Midwest town participated with four sixth-grade classes. After collecting their own data from a local water source, students created explanations by analyzing the data they collected (first-hand data), and by analyzing existing data set collected by another school from another river (second-hand data). By analyzing the health of these two water sources, students created two scientific explanations. Students participating in this study created stronger explanations when analyzing the data they generated (first-hand data). 相似文献