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31.
Upendra Yadav Pradeep Kumar Vandana Rai 《Indian journal of clinical biochemistry : IJCB》2021,36(1):23
Methionine synthase reductase (MTRR) is an important enzyme of the folate/homocysteine pathway. It is responsible for regulation of methionine enzyme by reductive methylation. A common variant A66G is reported in the FMN-binding domain of the MTRR gene, which leads to substitution of isoleucine by methionine (I22M) in MTRR enzyme with reduced activity. Reduced catalytic activity of enzyme leads to high homocysteine concentration in blood and increases risk for numerous diseases. The frequency of A66G polymorphism varies in different ethnic groups. The present study has been designed to evaluate the frequency of MTRR A66G gene polymorphism in the Eastern UP population by PCR–RFLP method. Along with this we also performed a meta-analysis to evaluate the global prevalence of this polymorphism. Databases were screened to identified the eligible studies. The prevalence of the G allele and GG genotype was determined by the use of prevalence proportion with 95% CI. Open meta-analyst software was used for the meta-analysis. Total 1000 blood samples were analyzed, the frequencies of A and G alleles were 0.35 and 0.65 respectively. Meta-analysis results revealed that the prevalence of G allele and GG genotype were 49.4% (95% CI 40.6–58.1, p ≤ 0.001) and 24.3% (95% CI 17.8–30.9, p ≤ 0.001) respectively. In sub-group meta-analysis, the lowest frequency of G allele was found in South America (32.7%; 95% CI 14.1–51.3, p ≤ 0.001), and highest in Asia (56.4%; 95% CI 39.5–73.3, p ≤ 0.001). The results of the meta-analysis showed that the Asian population has the highest frequency of G allele and highest frequency of the GG genotype was found in the European population. 相似文献
32.
In this study, a simple roller burnishing tool was made to operate burnishing processes on A356/5%SIC metal matrix composite fabricated by electromagnetic stir casting under different parameters. The effects of burnishing speed, burnishing force and number of burnishing passes on the surface roughness and tribological properties were measured. Scanning electron microscopy (SEM) graphs of the machined surface with PCD (insert-10) tool and roller burnished surface with tungsten carbide (WC) roller were taken into consider- ation to observe the surface finish of metal matrix composites. The mechanical properties (tensile strength, hardness, duc- tility) of A356/5%SIC metal matrix composites were studied for both unburnished samples and burnished samples. The results revealed that the roller burnished samples of A356/ 5%SIC led to the improvement in tensile strength, hardness and ductility. In order to find out the effects of roller bur- nishing process parameters on the surface roughness of A356/ 5%SIC metal matrix composite, response surface methodol- ogy (RSM) (Box-Behnken design) was used and a prediction model was developed relevant to average surface roughness using experimental data. In the range of process parameters, the result shows that roller burnishing speed increases, and surface roughness decreases, but on the other hand roller burnishing force and number of passes increase, and surface roughness increases. Optimum values of burnishing speed (1.5 m/s), burnishing force (50 N) and number of passes (2) during roller burnishing of A356/5%SIC metal matrix com- posite to minimize the surface roughness (predicted 1.232 μm) have been found out. There was only 5.03% error in the experimental and modeled results of surface roughness. 相似文献
33.
Kumar Laxman 《Journal of Research in Special Educational Needs》2022,22(2):158-166
This pilot study set out to examine the impact of a regular practice of yoga within schooling curricular hours on the well-being and behaviors of atypically developing children. The design of this study was based on a qualitative hermeneutic-phenomenology approach. The intervention consisted of 5 weekly sessions of yoga of 15 minutes each and composed of breathing techniques (pranayama), postures (pranayama), and lying down relaxation exercises (yoga nidra). The research site was a special needs school in South Auckland, New Zealand in an area characterized by poor socio-economic living conditions with a composite range of different ethnic groups. The findings of this study suggest that a regular practice of yoga can have numerous benefits for children on the Autism Spectrum Disorder (ASD). They found yoga to be a fun-filled and engaging experience. They improved significantly in their flexibility levels and general physical health. Emotionally, the children reported that the breathing techniques allowed them to feel calmer and more relaxed. The children felt that incorporating a regular practice of yoga within formal curriculum will be another effective tool to enhancing their overall health and well-being. 相似文献
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The University of Florida offers an online professional practice Ed.D. focused on Educational Technology. Twenty-three students have completed professional practice dissertations and graduated since the program’s inception in 2008. The purpose of this article is to share what these dissertations have looked like and to begin a dialogue about professional practice dissertations completed in online educational technology programs. Specifically, we (1) provide an overview of different ways professional practice Ed.D. dissertations are structured, (2) share guiding principles for professional practice dissertations in our Ed.D. program, (3) analyze the ways in which these guiding principles played out in the dissertations and (4) discuss the implications of our analysis for our program and for other online professional practice programs in Educational Technology. 相似文献
36.
Krishan Kumar. 《Higher Education Quarterly》1976,30(4):381-382
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India is one of the oldest civilizations with a kaleidoscopic variety and rich cultural heritage. It has achieved multi-faccted socio-economic progress during the last 47 years of its independence. This article reports on a survey of the usage of modern technologies (e.g. photocopiers, microfilming, computers, facsimile transmission, audio-visual, online searching and CD-ROMs) in Indian libraries. These libraries include university, engineering, scientific, medical, government and public libraries. The study used a questionnaire, personal visits to many libraries and interviews. The paper examines the impact of modern technologies on these libraries. It concludes with a summary of the problems faced by the librarians in adopting the modern technologies and suggests measures for implementation of modern technologies. 相似文献
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P.K. Kapur Hoang Pham Vijay Kumar Adarsh Anand 《The Journal of High Technology Management Research》2012,23(2):122-129
In this paper, a decision model is presented for the sales of software product to determine the profit and marketing policy under the influence of promotional efforts. The paper focuses on dependence of the optimal profit on the promotional efforts when there is diffusion effect of demand on the sales function. An elaborate optimization policy considering the dynamic nature of production cost function is proposed and numerical example is illustrated. The paper also studies the behavior of the future profit and its impact on profit maximization model by considering the constant price during the entire planning horizon. The experimental results greatly help us to identify the contributions of each selected parameter and its weight. Some conclusions, limitations of this study and future direction are also discussed. 相似文献