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411.
Moving mesh partial differential equations have been widely used in the last decade for solving differential equations exhibiting large solution variations such as shock waves and boundary layers.In this paper, we have applied a dynamic adaptive method for solving time-dependent differential equations. The mesh velocities are governed by an equation in which a relaxation time is employed to move nodes in such a way that they remain concentrated in regions of rapid variation of the solution. A numerical example involving a blow-up problem shows the advantage of using a variable relaxation time over a fixed one. 相似文献
412.
Mo’ath F. Bataineh Ali M. Al-Nawaiseh Mohammad H. Abu Altaieb David M. Bellar Omar S. Hindawi 《European Journal of Sport Science》2018,18(3):357-366
Mouth rinsing using a carbohydrate (CHO) solution has been suggested to improve physical performance in fasting participants. This study examined the effects of CHO mouth rinsing during Ramadan fasting on running time to exhaustion and on peak treadmill speed (Vpeak). In a counterbalanced crossover design, 18 sub-elite male runners (Age: 21?±?2 years, Weight: 68.1?±?5.7?kg, VO2max: 55.4?±?4.8?ml/kg/min) who observed Ramadan completed a familiarization trial and three experimental trials. The three trials included rinsing and expectorating a 25?mL bolus of either a 7.5% sucrose solution (CHO), a flavour and taste matched placebo solution (PLA) for 10?s, or no rinse (CON). The treatments were performed prior to an incremental treadmill test to exhaustion. Three-day dietary and exercise records were obtained on two occasions and analysed. Anthropometric characteristics were obtained and recorded for all participants. A main effect for mouth rinse on peak velocity (Vpeak) (CHO: 17.6?±?1.5?km/h; PLA: 17.1?±?1.4?km/h; CON: 16.7?±?1.2?km/h; P?.001, ηp2?=?0.49) and time to exhaustion (CHO: 1282.0?±?121.3?s; PLA: 1258.1?±?113.4?s; CON: 1228.7?±?98.5?s; P?=?.002, ηp2?=?0.41) was detected, with CHO significantly higher than PLA (P?.05) and CON (P?.05). Oxygen consumption, heart rate, respiratory exchange ratio, and rating of perceived exertion were not significantly different between treatments or trials (P?>?.05). Energy availability from dietary analysis, body weight, and fat-free mass did not change during the last two weeks of Ramadan (P?>?.05). This study concludes that carbohydrate mouth rinsing improves running time to exhaustion and peak treadmill speed under Ramadan fasting conditions. 相似文献
413.
414.
Nascent academic entrepreneurs need to acquire entrepreneurial competencies to create successful spin-off ventures. In this article, we examine difficulties in this pursuit prior to venture formation and offer a systematic classification of inhibitors. We confirm, combine, and extend two previously identified inhibiting mechanisms into a relational inhibitor category, classify additional structural and cultural-cognitive inhibitors, and highlight how these inhibitors exist both at the individual and the organizational level. We then advance theoretical understanding of the interrelated, multilevel functions of inhibitors on the development of entrepreneurial competencies, and offer policy insights on how universities can mitigate their effects. 相似文献
415.
Warren Chanda Thomson P. Joseph Xue-fang Guo Wen-dong Wang Min Liu Miza S. Vuai Arshad A. Padhiar Min-tao Zhong 《Journal of Zhejiang University. Science. B》2018,19(4):253-262
Microorganisms provide both beneficial and harmful effects to human beings. Beneficial effects come from the symbiotic relationship that exists between humans and microbiota, but then several human illnesses have turned some friendly microbes into opportunistic pathogens, causing several microbial-related diseases. Various efforts have been made to create and utilize antimicrobial agents in the treatment and prevention of these infections, but such efforts have been hampered by the emergence of antimicrobial resistance. Despite extensive studies on drug discovery to alleviate this problem, issues with the toxicity and tolerance of certain compounds and continuous microbial evolution have forced researchers to focus on screening various phytochemical dietary compounds for antimicrobial activity. Linolenic acid and its derivatives (eicosapentaenoic acid and docosahexaenoic acid) are omega-3 fatty acids that have been studied due to their role in human health, being important for the brain, the eye, the cardiovascular system, and general human growth. However, their utilization as antimicrobial agents has not been widely appreciated, perhaps due to a lack of understanding of antimicrobial mechanisms, toxicity, and route of administration. Therefore, this review focuses on the efficacy, mechanism, and toxicity of omega-3 fatty acids as alternative therapeutic agents for treating and preventing diseases associated with pathogenic microorganisms. 相似文献
416.
Undergraduate Research (UR) provides deeper experiential learning opportunities for students while increasing their self-efficacy, academic success and motivation to pursue graduate studies. Many real-world problems require an integrated solution and collaboration across different disciplines; therefore, it is important that students develop skills to work across disciplines on challenging research problems. As types and complexity of UR increase, Interdisciplinary Undergraduate Research (IDUR) has become more prevalent, but little is known about it. We define IDUR as “student-faculty collaboration to examine, increase, and share new knowledge or works relevant to research questions the investigation of which necessitates an interdisciplinary approach”. From the faculty perspective, and based on the results of a national sample of higher learning institutions in the U.S., we outline the enablers of and barriers to IDUR and provide quantitative and qualitative insights. Survey results show that, irrespective of the size of the institution at which they work, faculty members value mentoring students conducting IDUR although it brings with it some challenges. Our findings may help institutions better facilitate IDUR projects and inform faculty development opportunities that deepen student learning and retention via enhanced curricula in which IDUR is embedded. 相似文献
417.
Ali Azgor Talukder 《Cambridge Journal of Education》2018,48(2):213-226
Problematisation is the means by which critical pedagogy attempts to destabilise power relations related to gender, race, class, identity etc. Studies in critical pedagogy in language teaching explore different ways of problematisation treating problematisation as classroom practice. However, they do not specifically address the teacher’s struggle in employing problematisation and the learners’ experience with it in classroom settings. Hence the complexity of problematisation remains neglected in research in critical pedagogy in classroom contexts. This article explores the notion of problematisation through an analysis of a writing lesson involving undergraduate students in Bangladesh. It analyses both the teacher’s and a student’s encounters with and reflections on problematisation throughout the lesson, and reveals that problematisation embodies complexities, and is empowering when it is self-reflexive. 相似文献
418.
J. P. Prasad Y. Madhu Arushi Mandhan Payal Garg Anu Prakash Varsha Singh Daud Ali Prdeep Kumar Surinder Singh G. R. Soni Varun Singh 《Indian journal of clinical biochemistry : IJCB》2017,32(2):243-245
Current study is conducted to evaluate method verification of two locally available kits manufactured by DSI & BIORAD for quantitative estimation of Hepatitis B virus antibodies in human normal immunoglobulin by using International standard of National Institute of Biological Standards and Control. Four analyst perform five sets of test in duplicate analysing accuracy, precision, and limit of detection, sensitivity and specificity. Our results suggest that both DSI and BIORAD kits fulfil the validation criteria and are sensitive to detect up to 10 mIU concentration precisely and accurately. DSI kit is more precise at concentration 100 mIU and economically 4–5 times cheaper in local market; on the other hand, BIORAD kits provide larger detection range up to 1000 mIU. 相似文献
419.
Shanmugam Velayuthaprabhu Arunachalam Chinnathambi Sulaiman Ali Alharbi Hidehiko Matsubayashi Govindaraju Archunan 《Indian journal of clinical biochemistry : IJCB》2017,32(3):347-352
To investigate the effects of antiphospholipid antibodies on establishment of pregnancy and changes in hormones such as estradiol-17ß (E2) and progesterone (P) levels in circulation. Hence, mice were immunized with human β2-Glycoprotein I (β2GPI) and the effect of these antibodies on fetuses weight, placental obsrvation, Serum levels of P and E2 in pregnant mice, hematological were observed. Immunization of mice with human β2-GPI resulted in elevated levels of antiphospholipid antibodies. The experimentally induced antiphospholipid syndrome mouse showed higher rate of fetal resorption, low number of viable fetuses, and “placental abnormalities”. In these animals, serum E2 and P levels were reduced significantly. In addition, the blood cell variation among APS induced and control mice were determined. No significant variations were observed in number of Red Blood Cell count, White Blood Cell count and Hemoglobin content, while platelet number was significantly reduced as compared to control. These results clearly demonstrate that human β2-GPI might be involved in causing gestational failure in APS by exerting their effect on serum hormones. 相似文献
420.
巴基斯坦北部地区是历史上犍陀罗文化的中心区域,拥有大量的印度教、佛教和伊斯兰教文化遗址.借助考古文献资料、数字高程模型以及野外实地调查与验证数据,运用GIS空间分析方法,对巴基斯坦北部地区印度教、佛教和伊斯兰教文化遗址的时空分布特征、保存现状进行研究,并提出相应保护对策.结果 表明:巴基斯坦北部地区先后经历了印度教文化... 相似文献