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A Short-Term Measurement of PM2.5 Concentration During the COVID-19 Lockdown Period in Kathmandu Valley 加德满都谷地COVID-19封锁期间PM2.5浓度的短期测量
Pub Date : 2022-12-31 DOI: 10.3126/njst.v21i1.49916
P. K. Neupane, S. Shrestha, D. Rupakheti, D. Joshi, Tista Prasai Joshi
The Government of Nepal implemented a nationwide lockdown from 24 March 2020 to 21 July 2020 to control the person-to-person transmission of COVID-19. This study was conducted in a trafficintensified area of Kathmandu valley, where vehicular movement represents one of the main sources of air pollution. Hence, this study was intended to quantify the concentration of particulate matter (PM2.5) for 11 hours of daytime from 23 April to 20 May 2020. It was also to evaluate the influences of lockdown on air quality. PM2.5 was observed using HAZ-Dust, Environmental Particulate Air Monitor in the 18 different traffic sites of the Kathmandu valley. During the lockdown period, a substantially low mean concentration of PM2.5 ranging from 3.69±1.78 µg/ m3 to 7.58±3.98 µg/m3 was recorded in Kathmandu valley, which reflected improved air quality due to the cessation of vehicular activities. Therefore, the study outcome suggests that controlling the existing vehicular activities and promoting energy-efficient vehicles like electric vehicles in specific locations in the city will improve air quality and benefit public health.
尼泊尔政府从2020年3月24日至2020年7月21日在全国范围内实施了封锁,以控制COVID-19的人际传播。这项研究是在加德满都谷地的一个交通密集地区进行的,那里的车辆运动是空气污染的主要来源之一。因此,本研究旨在量化2020年4月23日至5月20日日间11小时的颗粒物(PM2.5)浓度。这也是为了评估封锁对空气质量的影响。在加德满都山谷的18个不同的交通站点,使用HAZ-Dust,环境颗粒空气监测仪观察PM2.5。在封锁期间,加德满都谷地的PM2.5平均浓度非常低,范围在3.69±1.78µg/m3至7.58±3.98µg/m3之间,这反映了车辆活动停止后空气质量得到改善。因此,研究结果表明,控制现有的车辆活动,在城市的特定地点推广节能汽车,如电动汽车,将改善空气质量,有利于公众健康。
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引用次数: 0
Development of Numerical Modeling for Finding Reflection and Transmission Coefficients in an Engineering Learning Paradigm of Computational Thinking 在计算思维的工程学习范式中寻找反射系数和透射系数的数值模型的发展
Pub Date : 2022-12-31 DOI: 10.3126/njst.v21i1.49959
Ikram E Khuda
In electromagnetics and antenna engineering, reflection and transmission coefficients are important parameters to be evaluated statistically and numerically to obtain effective computer simulations. This paper proposes a pedagogy to understand the development methodology of numerical reflection and transmission coefficient models. The proposed method employs relatively easy mathematics instead of the conventional ways that use difficult mathematics. These are then simulated as computer models. The study in this paper included a medium comprising of air and glass placed in it. Firstly, the region was divided into a gridded structure where the grids were mathematically formulated. Points on the grid were distinguished between different media using electrical permittivity and conductivity. The grids included boundary conditions and electric field wave propagation through them. Both boundary conditions and field equations were numerically modelled and discretized using the finite difference method with a proportional h2 error. This method provided a system of linear equations, which were then solved linearly to obtain the required reflection and transmission coefficients. An important aspect of the presented work is to provide an example approach for computational thinking (CT), which is now considered an important part of any engineering curriculum
在电磁学和天线工程中,反射系数和透射系数是进行统计和数值计算以获得有效计算机模拟的重要参数。本文提出了一种理解数值反射系数和透射系数模型的开发方法的教学法。所提出的方法采用相对简单的数学,而不是使用困难的数学传统方法。然后将其模拟成计算机模型。本文研究了一种由空气和放置在其中的玻璃组成的介质。首先,将该区域划分为网格结构,并对网格进行数学表示。利用介电常数和电导率来区分网格上的点。网格包括边界条件和电场波在其中的传播。采用有限差分法对边界条件和场方程进行了数值模拟和离散,误差为比例h2。该方法提供了一个线性方程组,然后对方程组进行线性求解,得到所需的反射系数和透射系数。所提出的工作的一个重要方面是为计算思维(CT)提供一个示例方法,这现在被认为是任何工程课程的重要组成部分
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引用次数: 0
In vitro Induction and Proliferation of Callus in Piper longum L. through Leaf Culture 长叶胡椒愈伤组织的离体诱导和叶片培养增殖
Pub Date : 2022-12-31 DOI: 10.3126/njst.v21i1.49892
C. Thapa, K. Pant, H. Bhattarai, B. Pant
Piper longum L. (Family Piperaceae) is a well- known health promoter used to treat cough, chronic bronchitis, asthma, and diabetes mellitus. The study is aimed to develop a protocol for callus induction and proliferation in P. longum. The leaf explants from mature plants were cultured on an MS basal medium supplemented with various concentrations of plant growth hormones, viz. 2,4-Dichlorophenoxyacetic acid (2, 4-D), Kinetin (KN), 6-Benzylaminopurine (BAP), and α-Naphthalene acetic acid (NAA), as well as 10% coconut water. In primary culture, the callus was compact and light white. The best callus induction and growth were observed in the MS basal medium containing1.0 mg/L 2,4-D+ 2.0 mg/L KN at 12 weeks of primary culture. At eight weeks of secondary culture, the MS medium containing 2.0 mg/L BAP alone and 0.5 mg/L NAA + 2.0 mg/L BAP and 10% coconut water had the best callus proliferation. Compared to 2,4-D and KN alone, BAP alone supported rapid callus growth in the MS medium. In P. longum, large-scale callus formation from leaf explants could be exploited to produce, isolate, and increase bioactive secondary metabolites for therapeutic purposes.
胡椒科胡椒是一种众所周知的健康促进剂,用于治疗咳嗽、慢性支气管炎、哮喘和糖尿病。本研究的目的是建立长叶青愈伤组织的诱导和增殖方法。将成熟植株叶片外植体培养在MS基础培养基上,培养基中添加不同浓度的植物生长激素,即2,4-二氯苯氧乙酸(2,4- d)、Kinetin (KN)、6-苄基氨基嘌呤(BAP)、α-萘乙酸(NAA)和10%椰子水。初代培养时愈伤组织致密,呈浅白色。初代培养12周时,MS基础培养基中添加1.0 mg/L 2,4- d + 2.0 mg/L KN的愈伤组织诱导和生长效果最好。二次培养8周时,MS培养基中仅含2.0 mg/L BAP和0.5 mg/L NAA + 2.0 mg/L BAP和10%椰子水的愈伤组织增殖效果最好。与单独使用2,4- d和KN相比,单独使用BAP在MS培养基中支持快速的愈伤组织生长。长叶杨叶片外植体形成的大规模愈伤组织可以产生、分离和增加具有生物活性的次生代谢物,用于治疗目的。
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引用次数: 0
First-Principles Study of Defected Single Layer Hexagonal Boron-Nitride (h-BN) 缺陷单层六方氮化硼(h-BN)的第一性原理研究
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45775
H. K. Neupane, N. Adhikari
The novel properties of pristine h-BN, oxygen (O) atom impurity defects in h-BN (h-B(N-O) and h-(B-O)N), one boron (1B) atom vacancy defect in h-BN (h-BN_1B) and one nitrogen (1N) atom vacancy defect in h-BN (h-BN_1N) materials are investigated by spin-polarized density functional theory (DFT) using computational tool Quantum ESPRESSO. We found that they are stable materials. From the band structure calculations, we found that all the considered systems are wide bandgap materials. The bandgap energy of pristine h-BN, impurity defects h-B(N-O) and h-(B-O)N, and vacancy defects h-BN_1B and h-BN_1Nmaterials have values 4.98 eV, 4.19 eV& 2.47 eV,and 4.84 eV& 3.62 eV respectively. Also, it is found that h-B(N-O) and h-BN_1N materials have n-type Schottky contact while h-(B-O)N and h-BN_1B materials have p-type Schottky contact. From the analysis ofdensity of states (DOS) and partial density of states (PDOS) calculations, we found that non-magnetic pristine h-BN changes to magnetic h-B(N-O) andh-(B-O)N materials due to presence of impurity defects,and h-BN_1B andh-BN_1N materials due to presence of vacancy defects. Magnetic moments of h-B(N-O), h-(B-O)N, h-BN_1B and h-BN_1N materials are 1.00 µB/cell, 0.94 µB/cell, 3.00 µB/cell and 1.00 µB/cell respectively. They are obtained due to unpaired up and down spins state of electrons in 2p orbital of B and N atoms in the structures.
利用量子ESPRESSO计算工具,利用自旋极化密度泛函理论(DFT)研究了原始h- bn、h- bn中氧(O)原子杂质缺陷(h- b (N-O)和h-(B-O)N)、h- bn中一个硼(1B)原子空位缺陷(h- bn_1b)和h- bn (h- bn_1n)材料中一个氮(1N)原子空位缺陷(h- bn_1n)的新性质。我们发现它们是稳定的材料。从带结构计算中,我们发现所有考虑的系统都是宽带隙材料。原始h- bn、杂质缺陷h- b (N- o)和h-(B-O)N、空位缺陷h- bn_1b和h- bn_1n材料的能带能分别为4.98 eV、4.19 eV和2.47 eV、4.84 eV和3.62 eV。h- b (N- o)和h- bn_1n材料具有N型肖特基接触,h-(B-O)N和h- bn_1b材料具有p型肖特基接触。通过对态密度(DOS)和偏态密度(PDOS)计算的分析,我们发现,由于杂质缺陷的存在,非磁性原始h-BN转变为磁性h-B(N- o)和h-(B-O)N材料,以及由于空位缺陷的存在,h-BN_1B和h- bn_1n材料。h-B(N- o)、h-(B- o)N、h- bn_1b和h- bn_1n材料的磁矩分别为1.00µB/cell、0.94µB/cell、3.00µB/cell和1.00µB/cell。它们是由于结构中B和N原子的2p轨道上电子的不成对的上下自旋状态而得到的。
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引用次数: 0
Food Green Cities: A Pathway to Sustainable Urban Development of Nepal 食品绿色城市:尼泊尔城市可持续发展之路
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45808
S. Shrestha
Urbanization is undergoing rapidly in Nepal. The causes are rural to urban migration and addition of municipalities by merging a number of rural areas. During the restructuring of the state, Government of Nepal declared 293 as municipalities among 753 local government units. Considering the municipalities as urban areas, urban population has reached more than sixty percent of Nepal’s total population. But the urban areas still have rural characteristics and insufficient infrastructures. Due to the increasing urbanization, the maintenance of sufficient open spaces, greeneries and the preservation of agricultural lands has become important urban issues in Nepal. The loss of productive lands has resulted in decrease of food self-sufficiency and green spaces in the cities. To tackle this urban issue, the Fourteenth National Development Plan has emphasized the concept of Food Green City (FGC) by integrating urban agriculture into urban planning. This paper aims to elaborate the concept of FGC and explore necessary policy intervention to realize the concept of FGC in practice based on the study of Godawari Municipality of Nepal. Finally, this study recommends FGC as a pathway for sustainable urban development of Nepal by highlighting FGC contribution in achieving Sustainable Development Goals (SDGs).
尼泊尔正在迅速城市化。其原因是农村人口向城市迁移和一些农村地区合并而增加的城市。在国家改组期间,尼泊尔政府宣布在753个地方政府单位中有293个为直辖市。将直辖市视为城市地区,城市人口已达到尼泊尔总人口的60%以上。但城市地区仍具有农村特色,基础设施不足。随着城市化进程的加快,保持足够的开放空间、绿化和保护农业用地已成为尼泊尔重要的城市问题。生产性土地的丧失导致城市粮食自给和绿地面积的减少。为了解决这一城市问题,第十四次国家发展规划强调了食品绿色城市(FGC)的概念,将城市农业纳入城市规划。本文旨在通过对尼泊尔戈达瓦里市的研究,阐述FGC的概念,并探讨在实践中实现FGC概念所需的政策干预。最后,本研究通过强调FGC对实现可持续发展目标(sdg)的贡献,建议将FGC作为尼泊尔可持续城市发展的途径。
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引用次数: 0
Nutritional value and antioxidant properties of Diospyros malabarica (Desr.) Kostel., fruit from midhills of western Nepal malabarica Diospyros的营养价值及抗氧化性能Kostel。产于尼泊尔西部中山的水果
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43361
R. Shrestha, Prabin Dawadi, Santosh Bhusal, Lok Ranjan Bhatt
Fruit consumption has long been recognized for its beneficial impact on human health. Persimmon fruit (Diospyros malabarica (Desr.) Kostel.) is a popular wild edible fruit distributed in mid-hill regions of Western Nepal and is used in treatment of various ailments by local people. Although, persimmon is a popular fruit, its significant nutritive values and bioactive compounds are still unexplored in Nepal. This research on nutritional and phytochemical analysis of persimmon fruit pulp was carried out using standardized analytical methods (Association of Official Analytical Chemists, AOAC) and microplate spectrophotometry with ultraviolet (UV) detection. The results revealed that the fruit is rich in sugar (66.52±2.17 mg /g), fiber (103.95 mg/g), ash (107.44 mg/g) and total phenolic content (112±2.89 mg GAEs/g) and the mild supplier of antioxidants.
长期以来,人们一直认为水果对人体健康有益。柿子(Diospyros malabarica)(Kostel.)是一种流行的野生食用水果,分布在尼泊尔西部的中山地区,当地人用它来治疗各种疾病。虽然,柿子是一种受欢迎的水果,但其重要的营养价值和生物活性化合物在尼泊尔仍未被开发。本研究采用标准化分析方法(美国官方分析化学家协会AOAC)和微孔板紫外分光光度法对柿子果肉进行营养和植物化学分析。结果表明,该果实富含糖(66.52±2.17 mg/g)、纤维(103.95 mg/g)、灰分(107.44 mg/g)和总酚(112±2.89 mg GAEs/g),是温和的抗氧化剂供应商。
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引用次数: 0
Complementing Food and Nutrition Security Using Toxin Minimizing Dry Chain and Integrated Pest Management: A Review 利用毒素最小化干链和病虫害综合治理补充粮食和营养安全:综述
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45804
S. Tiwari, K. Shrestha, Meghnath Dhima, J. Timsina, K. Belbase, P. Dahal
Global programs are involved to improve food and nutrition security in the low-and middle-income countries (LMICs). Increasing agrobiodiversity by maintaining local genetic resources has been proposed to achieve food and nutrition security. However, technology to maintain local germplasms/seed stocks are not available to the smallholders. This inability to save seeds translates into 25% annual low moisture food losses to rainfall/floods. As moisture builds up in improperly stored foods, insects, and carcinogenic molds proliferate along with nutrient loss. A dry chain (drying and moisture-proof packaging) could minimize these losses and even enable disaster resiliency. About 40% high moisture foods (fruits and vegetables) are lost due to lack of the cold chain facilities. Additionally, most people in the LMICs ingest artificial toxins daily through high moisture foods due to improper pesticide use. The prevalence of health compromising food toxins in nutritious foods has been complicating malnutrition alleviation efforts in the LMICs. Adopting Integrated Pest Management (IPM) strategies followed by sensitive monitoring could reduce pesticide residues to CODEX standards and enable healthy food systems. A way forward to achieve quality food and nutrition security in the post-Covid-19 era with a particular reference to LMICs like Nepal is presented.
全球计划旨在改善低收入和中等收入国家的粮食和营养安全。通过维护当地遗传资源来增加农业生物多样性已被提出以实现粮食和营养安全。但是,小农无法获得维持当地种质/种子储备的技术。由于无法保存种子,每年有25%的低水分粮食因降雨/洪水而损失。当水分在储存不当的食物中积累时,昆虫和致癌霉菌会随着营养物质的流失而繁殖。干燥链(干燥和防潮包装)可以最大限度地减少这些损失,甚至可以提高抗灾能力。大约40%的高水分食品(水果和蔬菜)由于缺乏冷链设施而丢失。此外,由于不当使用农药,中低收入国家的大多数人每天通过高水分食品摄入人工毒素。营养食品中普遍存在危害健康的食物毒素,使中低收入国家减轻营养不良的努力复杂化。采用虫害综合治理战略并辅以敏感监测,可将农药残留降低至食品法典委员会标准,并建立健康的食品体系。本文提出了在后covid -19时代实现高质量粮食和营养安全的前进道路,并特别提到了尼泊尔等中低收入国家。
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引用次数: 0
Electrochemical Characterization of Electrodeposited Ni-titanium Dioxide Deposits on Copper and their Corrosion Study 电沉积镍-二氧化钛在铜表面的电化学表征及其腐蚀研究
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43347
K. Berarma, A. Raghdi, Ghania Benaiche
This work aimed to produce and characterize composite coatings of nickel incorporating TiO2 nanoparticles on a copper substrate. These deposits were obtained from watts bath. In the study, the cyclic voltammetry technique was employed to provide a better understanding of the cathodic behavior of nickel deposition. The effects of the potential scanning rate and the effect of cathodic limits on cyclic voltammograms deposition of Ni in Primitive Watts Bath (BWP) were determined. The composite coatings of nickel incorporating TiO2 nanoparticles were characterized using various electrochemical techniques such as open circuit potential (OCP) and potentiodynamic polarization measurements, and electrochemical impedance spectroscopic methods. The current density values for the Ni-TiO2 in the case of 5 g/L and 10 g/L of TiO2 determined from the polarization curves recorded in 3.5% NaCl indicate that the corrosion process on nickel incorporating the TiO2 nanoparticle composite surface is slower than on pure nickel. The TiO2 particles embedded in the electroplated nickel, increase the polarization resistance and decrease the corrosion rates as compared with electrodeposited pure nickel. Electrochemical impedance spectra obtained at the open-circuit potential ( OCP) in 3.5% NaCl showed an increase of polarization resistance with time in all cases.
这项工作的目的是在铜衬底上制备和表征含TiO2纳米颗粒的镍复合涂层。这些沉积物是从瓦氏浴中获得的。在这项研究中,循环伏安技术被用于更好地了解镍沉积的阴极行为。研究了电位扫描速率和阴极极限对镍在原始瓦浴(BWP)中循环伏安沉积的影响。采用各种电化学技术,如开路电位(OCP)和动电位极化测量,以及电化学阻抗谱方法,对含TiO2纳米颗粒的镍复合涂层进行了表征。在3.5% NaCl溶液中测定5 g/L和10 g/L TiO2浓度下Ni-TiO2的电流密度值表明,含TiO2纳米颗粒复合表面的镍的腐蚀过程比纯镍慢。与电沉积纯镍相比,TiO2颗粒嵌入在电镀镍中,增加了极化电阻,降低了腐蚀速率。在3.5% NaCl开路电位(OCP)下得到的电化学阻抗谱显示,在所有情况下极化电阻都随时间增加。
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引用次数: 0
COVID-19: Knowledge, Attitudes, and Practices among the Scholarly Cohorts of Nepal 2019冠状病毒病:尼泊尔学者群体的知识、态度和做法
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i2.45777
M. Sharma, S. Khanal, J. Acharya, R. Adhikari, C. Budhathoki
COVID-19 is an infectious disease caused by a newly discovered microorganism called corona virus, a pandemic. Knowledge, attitudes and practices are prime components that play a crucial role in spreading the disease. These elements would support focusing on the people with underlying medical problems, and old-aged people, including children, are more likely to be susceptible. The main objective of this study was to assess the knowledge, attitude, and practices amongst the students, teachers, and health workers, including staff members of the NGOs/INGOs. This cross-sectional study was done, including 224 respondents. A self-administered-structured questionnaire comprised of nineteen structured questions exploring the pandemic’s knowledge, attitudes and practices was done. The data were analyzed using the Statistical Package for the Social Sciences (SPSS) software version 25.0. Of the total, 67.4% were males, and 32.6% were females. Nearly 50% of the respondents were with M-Phil/PhD degrees, while 4.9% had a secondary level. The study revealed that 28.0% of the participants knew about the pandemic, 41.0% had positive attitudes, and 54.0% experienced good practices. The knowledge level on the pandemic was statistically significant where attitudes and practices were poor. This study suggests that public health approaches such as awareness, masseducation campaigns, etc., are urgently required to control the outbreaks strongly associated with the community’s knowledge, attitudes, and behaviours.
COVID-19是一种传染病,由新发现的冠状病毒引起,这是一种大流行。知识、态度和做法是在疾病传播中发挥关键作用的主要因素。这些因素将支持把重点放在有潜在医疗问题的人身上,老年人,包括儿童,更容易受到影响。本研究的主要目的是评估学生、教师和卫生工作者(包括非政府组织/非政府组织的工作人员)的知识、态度和做法。这是一项横断面研究,包括224名受访者。完成了一份自我管理的结构化问卷,其中包括19个结构化问题,探讨了大流行病的知识、态度和做法。使用SPSS 25.0版社会科学统计软件包(Statistical Package for The Social Sciences)软件对数据进行分析。男性占67.4%,女性占32.6%。近50%的受访者拥有硕士/博士学位,而4.9%的受访者拥有二级学位。研究表明,28.0%的参与者了解大流行,41.0%的参与者持积极态度,54.0%的参与者采取了良好做法。在态度和做法较差的地方,对这一流行病的了解程度在统计上很显著。这项研究表明,迫切需要采取公共卫生措施,如提高认识、群众宣传运动等,以控制与社区知识、态度和行为密切相关的疫情。
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引用次数: 1
Detection of Common β-Globin Gene Mutation in Eastern Nepal by Multiplex Amplification Refractory Mutation System Polymerase Chain Reaction System 多重扩增难突变聚合酶链反应系统检测尼泊尔东部常见β-珠蛋白基因突变
Pub Date : 2021-12-31 DOI: 10.3126/njst.v20i1.43358
Gita Shrestha, N. Singh, Priti Shrestha, C. Baniya
β-thalassemia is the most common autosomal recessive haemoglobin disorder worldwide. Although more than 200 β-thalassemia mutations have been reported, few ethnic group-specific alleles account for 90-93% of the β-thalassemia alleles in each population. The primary purpose of the study was to identify the prevalence of different types of beta-thalassemia mutations in the study group, and to establish a genotype-phenotype correlation. Complete blood count, peripheral blood smeacr, capillary electrophoresis and multiples arms refractory mutation system based polymerase chain reaction (MARMS) were performed on the peripheral blood samples to detect beta mutations at Decode Genomics and Research Centre, Sinamangal Kathmandu. The MARMS-PCR technique was applied for the detection of nine common mutations IVS1- 5(G>C), 619 bp del, FS8/9 (+G), IVS1-1 (G>T), FS 41/42 (-CTTT), C-15 (G>A). FS 16 (-C), C-30 (G>C) and C-5 (-CTCT). In the study group, three mutations, C-15(G>A), C-26 (Glu-Lys) and IVS1-5 (G>C) were detected. The study revealed a characteristic mutational profile in the five ethnic groups of eastern Nepal. It is the first report of HbE in the Koch Rajbanshi of eastern Nepal. The mutation C-15 reported as rare by earlier workers was the most common mutation identified in this research work.
β-地中海贫血是世界上最常见的常染色体隐性血红蛋白疾病。尽管已经报道了200多个β-地中海贫血突变,但少数民族特异性等位基因占每个人群β-地中海贫血等位基因的90-93%。该研究的主要目的是确定研究组中不同类型-地中海贫血突变的患病率,并建立基因型-表型相关性。在加德满都Sinamangal Decode基因组学和研究中心,对外周血样本进行全血细胞计数、外周血涂片、毛细管电泳和基于聚合酶链反应(MARMS)的多臂难解突变系统检测β突变。采用MARMS-PCR技术检测9个常见突变IVS1- 5(G>C)、619 bp del、FS8/9 (+G)、IVS1-1 (G>T)、FS 41/42 (- cttt)、C-15 (G>A)。fs16 (-C), C-30 (G>C)和C-5 (-CTCT)。研究组检测到C-15(G>A)、C-26 (Glu-Lys)和IVS1-5 (G>C) 3个突变。这项研究揭示了尼泊尔东部5个民族的典型突变特征。这是尼泊尔东部科赫拉杰班什地区首次报道HbE。早期工人报道的罕见突变C-15是本研究工作中发现的最常见的突变。
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引用次数: 0
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Nepal Journal of Science and Technology
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