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81.

Objective  

The roles of gonadal hormones and nitric oxide (NO) on the analgesic effects of morphine, tolerance to morphine, and their interactions have been widely investigated. In the present study, the effect of l-arginine (an NO precursor) on morphine tolerance in sham and ovariectomized (OVX) female mice was investigated.  相似文献   
82.
This study seeks to describe the teachers’ professional development activities in Bangladesh and explores the hypotheses about the relationship between teachers’ traditional professional development activities and school improvement. Data from a representative sample of City secondary schools from Bangladesh (n = 127) were gathered through questionnaires from 127 principals and 694 teachers. Hierarchical multiple regression analysis was used in this research. This study found significant impacts of some of teachers’ professional development activities on school improvement. Also found that the maximum school improvement can be achieved if schools put more emphasis on teachers’ collaboration, in-service training and classroom observation and less emphasis on individual action enquiry. The findings of this study provide important information for the policy makers, educational managers and especially for the headmasters and teachers concerned with the improvement of teachers’ quality in secondary schools of Bangladesh. This study adopts a concurrent approach of data collection and analysis.  相似文献   
83.
We report on low-cost fabrication and high-energy density of full-cell lithium-ion battery (LIB) models. Super-hierarchical electrode architectures of Li2SiO3/TiO2@nano-carbon anode (LSO.TO@nano-C) and high-voltage olivine LiMnPO4@nano-carbon cathode (LMPO@nano-C) are designed for half- and full-system LIB-CR2032 coin cell models. On the basis of primary architecture-power-driven LIB geometrics, the structure keys including three-dimensional (3D) modeling superhierarchy, multiscale micro/nano architectures and anisotropic surface heterogeneity affect the buildup design of anode/cathode LIB electrodes. Such hierarchical electrode surface topologies enable continuous in-/out-flow rates and fast transport pathways of Li+-ions during charge/discharge cycles. The stacked layer configurations of pouch LIB-types lead to excellent charge/discharge rate, and energy density of 237.6 Wh kg−1. As the most promising LIB-configurations, the high specific energy density of hierarchical pouch battery systems may improve energy storage for long-driving range of electric vehicles. Indeed, the anisotropic alignments of hierarchical electrode architectures in the large-scale LIBs provide proof of excellent capacity storage and outstanding durability and cyclability. The full-system LIB-CR2032 coin cell models maintain high specific capacity of ∼89.8% within a long-term life period of 2000 cycles, and average Coulombic efficiency of 99.8% at 1C rate for future configuration of LIB manufacturing and commercialization challenges.  相似文献   
84.
The literacy practices of many communities today show new ways of meaning making in the contemporary, technological and digital culture. A number of Malaysian adolescents belong to this culture. This pilot study reports the preliminary findings of a larger study aimed at describing the online activities of Malaysian adolescents. Fifty‐four participants from an urban secondary school in Penang took part in this study. One finding showed that the percentages of language use on the Internet were: 80.6 per cent in English, 10.6 per cent in Bahasa Malaysia and 8.8 per cent in Chinese. In addition, the study also revealed some common websites that these adolescents frequented. The findings point to the need to investigate the extent of these online literacy practices beyond school among the adolescent population in Malaysia and to look into the implications for ESL education.  相似文献   
85.
Educational Research for Policy and Practice - Much has been written, published, and presented about the important role and uses of technology in English language teaching (ELT) today and the...  相似文献   
86.
The purpose of the current study was to investigate the effectiveness of interacting with animations using mobile devices on grade 12 students’ spatial and reasoning abilities. The study took place in a grade 12 context in Oman. A quasi-experimental design was used with an experimental group of 32 students and a control group of 28 students. The experimental group studied chemistry using mobile tablets that had a digital instructional package with different animation and simulations. There was one tablet per student. A spatial ability test and a scientific reasoning test were administered to both groups prior and after the study, which lasted for 9 weeks. The findings showed that there were significant statistical differences between the two groups in terms of spatial ability in favour of the experimental group. However, there were no differences between the two groups in terms of reasoning ability. The authors reasoned that the types of animations and simulations used in the current study featured a wide range of three-dimensional animated illustrations at the particulate level of matter. Most probably, this decreased the level of abstractness that usually accompanies chemical entities and phenomena and helped the students to visualize the interactions between submicroscopic entities spatially. Further research is needed to decide on types of scientific animations that could help students improve their scientific reasoning.  相似文献   
87.
Vaccines require optimal adjuvants including immunopotentiator and delivery systems to offer long term protection from infectious diseases in animals and man. Initially it was believed that adjuvants are responsible for promoting strong and sustainable antibody responses. Now it has been shown that adjuvants influence the isotype and avidity of antibody and also affect the properties of cell-mediated immunity. Mostly oil emulsions, lipopolysaccharides, polymers, saponins, liposomes, cytokines,ISCOMs (immunostimulating complexes), Freund's complete adjuvant, Freund's incomplete adjuvant, alums, bacterial toxins etc.,are common adjuvants under investigation. Saponin based adjuvants have the ability to stimulate the cell mediated immune system as well as to enhance antibody production and have the advantage that only a low dose is needed for adjuvant activity. In the present study the importance of adjuvants, their role and the effect of saponin in immune system is reviewed.  相似文献   
88.
The literature shows an increase in blended learning implementations (N?=?74) at faculties of education in Turkey whereas pre-service and in-service teachers’ ICT competencies have been identified as one of the areas where they are in need of professional development. This systematic review was conducted to find out the impact of blended learning on academic achievement and attitudes at teacher education programs in Turkey. 21 articles and 10 theses complying with all pre-determined criteria (i.e., studies having quantitative research design or at least a quantitative aspect conducted at pre-service teacher education programs) included within the scope of this review. With regard to academic achievement, it was synthesized that majority of the studies confirmed its positive impact on attaining course outcomes. Likewise, blended learning environment was revealed to contribute pre-service teachers to develop positive attitudes towards the courses. It was also concluded that face-to-face aspect of the courses was favoured considerably as it enhanced social interaction between peers and teachers. Other benefits of blended learning were listed as providing various materials, receiving prompt feedback, and tracking progress. Slow internet access, connection failure and anxiety in some pre-service teachers on using ICT were reported as obstacles. Regarding the positive results of blended learning and the significance of ICT integration, pre-service teacher education curricula are suggested to be reconstructed by infusing ICT into entire program through blended learning rather than delivering isolated ICT courses which may thus serve for prospective teachers as catalysts to integrate the use of ICT in their own teaching.  相似文献   
89.
Basic science courses are extremely important as a foundation for scaffolding knowledge and then applying it in future courses, clinical situations as well as in a professional career. Anatomical sciences, which include tooth morphology, oral histology, oral embryology, and head and neck anatomy form a core part of the preclinical courses in dental technology programs. In this article, the importance and relevance of anatomical sciences to dental personnel with no direct contact with patients (dental technicians) and limited discipline related contact with patients (dental prosthetists) is highlighted. Some light is shed on the role of anatomical sciences in the pedagogical framework and its significance in the educational process and interprofessional learning of dental technicians and prosthetists using oral biology as an example in the dental curriculum. To conclude, anatomical sciences allow dental technicians and prosthetists to a gain a better insight of how tissues function, leading to a better understanding of diagnosis, comprehensive treatment planning and referrals if needed. Patient communication and satisfaction also increases as a result of this deep understanding of oral tissues. Anatomical sciences bridge the gap between basic science, preclinical, and clinical courses, which leads to a holistic approach in patient management. Finally, treatment outcomes are positively affected due to the appreciation of the macro and micro structure of oral tissues. Anat Sci Educ 10: 395–404. © 2016 American Association of Anatomists.  相似文献   
90.
In this paper we investigate the cooperative tracking control problem with quantized time delay information exchange for a group of wheeled mobile robots networked through a connected graph modeling the underlying communication topology. A cooperative controller is proposed using a combination of backstepping technique, graph theory and neural network radial basis functions. We show, using the small gain theorem, that the states of each mobile robot in the group converge to and remain inside a tube centered around its assigned trajectory to form a desired geometric pattern whose centroid is assumed to move along a predefined trajectory. Experimental results on a group of three mobile robots forming a triangular shape are presented to demonstrate the good performance of the proposed cooperative controller.  相似文献   
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