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Examining the Use of Scott’s Formula and Link Expiration Time Metric for Vehicular Clustering
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作者 Fady Samann Shavan Askar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2421-2444,共24页
Implementing machine learning algorithms in the non-conducive environment of the vehicular network requires some adaptations due to the high computational complexity of these algorithms.K-clustering algorithms are sim... Implementing machine learning algorithms in the non-conducive environment of the vehicular network requires some adaptations due to the high computational complexity of these algorithms.K-clustering algorithms are simplistic,with fast performance and relative accuracy.However,their implementation depends on the initial selection of clusters number(K),the initial clusters’centers,and the clustering metric.This paper investigated using Scott’s histogram formula to estimate the K number and the Link Expiration Time(LET)as a clustering metric.Realistic traffic flows were considered for three maps,namely Highway,Traffic Light junction,and Roundabout junction,to study the effect of road layout on estimating the K number.A fast version of the PAM algorithm was used for clustering with a modification to reduce time complexity.The Affinity propagation algorithm sets the baseline for the estimated K number,and the Medoid Silhouette method is used to quantify the clustering.OMNET++,Veins,and SUMO were used to simulate the traffic,while the related algorithms were implemented in Python.The Scott’s formula estimation of the K number only matched the baseline when the road layout was simple.Moreover,the clustering algorithm required one iteration on average to converge when used with LET. 展开更多
关键词 CLUsTERING vehicular network scott’s formula FastPAM
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LEIBNIZ′FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF DIFFERENTIAL OPERATORS AND RECURRENCE FORMULA OF THEIR GREEN′S FUNCTION 被引量:1
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作者 许跃生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1359-1364,共6页
In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green fun... In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green function about the operators is also given. 展开更多
关键词 LEIBNIZ s FUNCTION formula OF GENERALIZED DIFFERENCE WITH REsPECT TO A CLAss OF DIFFERENTIAL OPERATORs AND RECURRENCE formula OF THEIR green
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A hybrid method integrating Green's function Monte Carlo and projected entangled pair states
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作者 He-Yu Lin Rong-Qiang He +1 位作者 Yibin Guo Zhong-Yi Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期75-81,共7页
This paper introduces a hybrid approach combining Green’s function Monte Carlo(GFMC)method with projected entangled pair state(PEPS)ansatz.This hybrid method regards PEPS as a trial state and a guiding wave function ... This paper introduces a hybrid approach combining Green’s function Monte Carlo(GFMC)method with projected entangled pair state(PEPS)ansatz.This hybrid method regards PEPS as a trial state and a guiding wave function in GFMC.By leveraging PEPS’s proficiency in capturing quantum state entanglement and GFMC’s efficient parallel architecture,the hybrid method is well-suited for the accurate and efficient treatment of frustrated quantum spin systems.As a benchmark,we applied this approach to study the frustrated J_(1)–J_(2) Heisenberg model on a square lattice with periodic boundary conditions(PBCs).Compared with other numerical methods,our approach integrating PEPS and GFMC shows competitive accuracy in the performance of ground-state energy.This paper provides systematic and comprehensive discussion of the approach of our previous work[Phys.Rev.B 109235133(2024)]. 展开更多
关键词 projected entangled pair states greens function Monte Carlo frustrated J_(1)-J_(2)Heisenberg model
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Implementation of the Integrated Green’s Function Method for 3D Poisson’s Equation in a Large Aspect Ratio Computational Domain
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作者 Ji Qiang Chad Mitchell +1 位作者 Remi Lehe Arianna Formenti 《Journal of Software Engineering and Applications》 2024年第9期740-749,共10页
The solution of Poisson’s Equation plays an important role in many areas, including modeling high-intensity and high-brightness beams in particle accelerators. For the computational domain with a large aspect ratio, ... The solution of Poisson’s Equation plays an important role in many areas, including modeling high-intensity and high-brightness beams in particle accelerators. For the computational domain with a large aspect ratio, the integrated Green’s function method has been adopted to solve the 3D Poisson equation subject to open boundary conditions. In this paper, we report on the efficient implementation of this method, which can save more than a factor of 50 computing time compared with the direct brute force implementation and its improvement under certain extreme conditions. 展开更多
关键词 greens Function Poisson Equation Particle Accelerator
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Reciprocity Relation between Alternative Gravity Formulas
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2024年第4期1432-1440,共9页
We compare Newton’s force law of universal gravitation with a corrected simple approach based on Bhandari’s recently presented work, where the gravitation constant G is maintained. A reciprocity relation exists betw... We compare Newton’s force law of universal gravitation with a corrected simple approach based on Bhandari’s recently presented work, where the gravitation constant G is maintained. A reciprocity relation exists between both alternative gravity formulas with respect to the distances between mass centers. We conclude a one-to-one mapping of the two gravitational formulas. We don’t need Einstein’s construct of spacetime bending by matter. 展开更多
关键词 Gravity formulas Reciprocity Distance Relation NEWTON EINsTEIN Bhandari Higgs Field Dirac’s Large Number
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem sign-Changing greens Function Fixed Point Index Iterative Technique Monotone Positive solution EXIsTENCE
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Green Function of Generalized Time Fractional Diffusion Equation Using Addition Formula of Mittag-Leffler Function
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作者 Fang Wang Jinmeng Zhang 《Journal of Applied Mathematics and Physics》 2022年第9期2720-2732,共13页
In this paper, we use the Mittag-Leffler addition formula to solve the Green function of generalized time fractional diffusion equation in the whole plane and prove the convergence of the Green function.
关键词 Mittag-Leffler Function Mellin Transforms Generalized Time Fractional Diffusion Equation green Function Addition formula
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Quasi-Dynamic Green’s Functions for Efficient Full-Wave Integral Formulations for Microstrip Interconnects
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作者 Andrea G. Chiariello Antonio Maffucci 《Journal of Electromagnetic Analysis and Applications》 2012年第2期69-76,共8页
Integral formulations are widely used for full-wave analysis of microstrip interconnects. A weak point of these formulations is the inclusion of the proper planar-layered Green’s Functions (GFs), because of their com... Integral formulations are widely used for full-wave analysis of microstrip interconnects. A weak point of these formulations is the inclusion of the proper planar-layered Green’s Functions (GFs), because of their computational cost. To overcome this problem, usually the GFs are decomposed into a quasi-dynamic term and a dynamic one. Under suitable approximations, the ?rst may be given in closed form, whereas the second is approximated. Starting from a general criterion for this decomposition, in this paper we derive some simple criteria for using the closed-form quasi-dynamic GFs instead of the complete GFs, with reference to the problem of evaluating the full-wave current distribution along microstrips. These criteria are based on simple relations between frequency, line length, dielectric thickness and permittivity. The layered GFs have been embedded into a full-wave transmission line model and the results are ?rst benchmarked with respect to a full-wave numerical 3D tool, then used to assess the proposed criteria. 展开更多
关键词 Full-Wave MODELs greens FUNCTION INTEGRAL formulations MICROsTRIP Interconnects
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Singularity-free Green's function for EM sources embedded in a stratified medium 被引量:3
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作者 翁爱华 刘云鹤 +1 位作者 殷长春 贾定宇 《Applied Geophysics》 SCIE CSCD 2016年第1期25-36,217,218,共14页
We present a method to unify the calculation of Green's functions for an electromagnetic(EM) transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is intro... We present a method to unify the calculation of Green's functions for an electromagnetic(EM) transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is introduced through the source location.The potentials for Green's function are derived by decomposing the partial wave solutions to Helmholtz's equations into upward and downward within boundaries.The amplitudes of the potentials in each stratum are obtained recursively from the initial amplitudes at the source level.The initial amplitudes are derived by coupling with the transmitting sources and following the discontinuity of the tangential electric and magnetic fields at the source interface.Only the initial terms are related to the transmitting sources and thus need to be modified for different transmitters,whereas the kernel connected with the stratified media stays unchanged.Hence,the present method can be easily applied to EM transmitting sources with little modification.The application of the proposed method to the marine controlled-source electromagnetic method(MCSEM) demonstrates its simplicity and flexibility. 展开更多
关键词 EM Marine EM greens function stratified medium sINGULARITY
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The Green's function of the harmonic horizontal force applied at the interior of the saturated half-space soil 被引量:10
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作者 陆建飞 王建华 沈为平 《地震学报》 CSCD 北大核心 2001年第2期185-191,共7页
By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equ... By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equations in frequency domain are established through the use of Hankel integral transforms technique. Utilizing the above- mentioned general solutions, and the boundary conditions of the surface of the half-space and the continuous conditions at the plane of the horizontal force, the solutions of the boundary value problem can be determined. By the numerical inverse Hankel transforms method, the Green(s functions of the harmonic horizontal force are obtainable. The degenerate case of the results deduced from this paper agrees well with the known results. Two numerical examples are given in the paper. 展开更多
关键词 BIOT理论 HANKEL变换 green函数 非轴对称 非饱和土 简谐水平力
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New Color-Difference Formula Based on CIECAM97s 被引量:1
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作者 宦晖 李为 赵达尊 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期149-152,共4页
To deduce a new color difference formula based on CIE 1997 Color Appearance Model(CIECAM97s), a color space J a 1 b 1 is first constructed with color appearance descriptors J,a,b in CIECAM97s. The new f... To deduce a new color difference formula based on CIE 1997 Color Appearance Model(CIECAM97s), a color space J a 1 b 1 is first constructed with color appearance descriptors J,a,b in CIECAM97s. The new formula is then deduced in the space and named CDF CIECAM97s. The factors for lightness, chroma and hue correction in the formula are derived by linear regression according to BFD? CP data sets. It is found by statistical analysis that CDF CIECAM97s is in closer accordance with the visual assessments when compared with CMC(1∶1), CIE94 and CIE L *a *b * color difference formulae. Based on color appearance model, the new color difference formula can be used to predict color difference perception in a varity of different viewing conditions. 展开更多
关键词 CIECAM97s color difference formulae color space
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基于Ackermann's formula的类反斜线回滞系统滑模控制 被引量:1
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作者 张达科 胡跃明 郭华芳 《机械工程学报》 EI CAS CSCD 北大核心 2005年第1期11-15,共5页
回滞现象广泛地存在于许多机械控制领域。由于回滞特性具有不可微性,从而使得对回滞系统的控制变得困难和复杂,同时由于回滞可能引起系统的振荡,甚至造成系统的不稳定,因此有必要对回滞系统的有效控制进行研究。考虑到回滞系统建模仍然... 回滞现象广泛地存在于许多机械控制领域。由于回滞特性具有不可微性,从而使得对回滞系统的控制变得困难和复杂,同时由于回滞可能引起系统的振荡,甚至造成系统的不稳定,因此有必要对回滞系统的有效控制进行研究。考虑到回滞系统建模仍然是个研究的领域,针对类反斜线回滞系统进行研究。把类反斜线回滞模型分解为确定的线性部分和已知上界的不确定非线性部分,利用Ackermann's formula给出了类反斜线回滞系统的滑模控制律。仿真表明此滑模控制律是有效的,同时此滑模控制保证了整个系统的稳定性。 展开更多
关键词 类反斜线回滞 滑模控制 Ackermann’s formula
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SYBR GreenⅠ实时荧光PCR检测食品中转基因成分方法的初步建立 被引量:2
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作者 王燕梅 刘衡川 梁疆莉 《江苏预防医学》 CAS 2009年第1期12-14,共3页
目的:建立SYBR GreenⅠ实时荧光PCR方法检测食品中转基因成分35S启动子和NOS终止子,并对样品进行检测。方法:以大豆Lectin基因为内源性基因,以转基因食品中常用的花椰菜花叶病毒启动子(Ca MV35S)和根癌农杆菌终止子(NOS)基因为目标基因... 目的:建立SYBR GreenⅠ实时荧光PCR方法检测食品中转基因成分35S启动子和NOS终止子,并对样品进行检测。方法:以大豆Lectin基因为内源性基因,以转基因食品中常用的花椰菜花叶病毒启动子(Ca MV35S)和根癌农杆菌终止子(NOS)基因为目标基因,设计并合成3对特异性引物,优化反应条件,使用SYBR GreenⅠ染料实时荧光PCR检测35S启动子和NOS终止子,并做熔解曲线分析。同时利用该方法对胡萝卜、青豆、玉米、马铃薯等实际样品进行检测。结果:运用该方法检测8份样品,有4份检出35S基因和NOS基因成分。结论:SYBR GreenⅠ实时荧光PCR方法能有效检测出35S和NOS两种转基因成分,简便、快速。 展开更多
关键词 转基因 sYBR green Ⅰ实时荧光PCR 35s NOs
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具有转移条件的两个区间Sturm-Liouville算子的Green函数和渐近展开(英文) 被引量:2
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作者 牡丹 孙炯 姚斯琴 《应用数学》 CSCD 北大核心 2014年第3期658-672,共15页
考虑具有转移条件的两个区间Sturm-Liouville算子.定义与转移条件相关联的的Hilbert空间,并在新Hilbert空间里讨论两个区间Sturm-Liouville算子.进一步构造具有转移条件的两个区间Sturm-Liouville算子的Green函数,并且给出两个区间Sturm... 考虑具有转移条件的两个区间Sturm-Liouville算子.定义与转移条件相关联的的Hilbert空间,并在新Hilbert空间里讨论两个区间Sturm-Liouville算子.进一步构造具有转移条件的两个区间Sturm-Liouville算子的Green函数,并且给出两个区间Sturm-Liouville算子的特征值和特征函数的渐近展开. 展开更多
关键词 两个区间sturm-Liouville算子 渐近展开 green函数
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纳米分子器件量子传导中的Green's Function模型
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作者 王利光 李勇 +1 位作者 郁鼎文 Katsunori TAGAMI 《黑龙江大学自然科学学报》 CAS 北大核心 2005年第2期213-215,共3页
将纳米分子器件的电极和分子本体作为一个系统,考虑到入射电子在原子电极和分子本体中的传导,在电极与分子之间界面上的透射的量子状态,在满足Fisher-Lee关系式的基础上,一个新型的Green’sFunction被设计出来。这一理论模型把三个区域... 将纳米分子器件的电极和分子本体作为一个系统,考虑到入射电子在原子电极和分子本体中的传导,在电极与分子之间界面上的透射的量子状态,在满足Fisher-Lee关系式的基础上,一个新型的Green’sFunction被设计出来。这一理论模型把三个区域上的不同量子状态完整地表达在一个方程式里,符合物理学基本原理,可以系统地用来研究纳米分子器件的量子传导特性。 展开更多
关键词 纳米分子器件 量子传导 greens FUNCTION
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(S,T)-双系上的Green′s关系及其稳定性
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作者 高振林 赵根灵 《上海理工大学学报》 CAS 北大核心 2010年第4期385-390,共6页
建立(S,T)-双系M上的Green′s关系理论.利用其基本性质讨论M的稳定性.将M的稳定性应用到半群上使得半群理论中的平行经典结果成为其特例,而有些却成为半群理论中的新结果.
关键词 (s T)-双系 green′s关系 (s T)-子系 稳定(s T)-双系
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两区间Sturm-Liouville问题Green函数及修正Parseval等式(英文)
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作者 牡丹 孙炯 姚斯琴 《应用数学》 CSCD 北大核心 2014年第4期827-843,共17页
本文研究具有转移条件的两区间Sturm-Liouville问题.首先得到参数λ是两区间Sturm-Liouville问题的特征值的充要条件,并证明两区间Sturm-Liouville问题的Green函数按特征函数的展开,最后利用Green函数按特征函数的展开证明了修正Parseva... 本文研究具有转移条件的两区间Sturm-Liouville问题.首先得到参数λ是两区间Sturm-Liouville问题的特征值的充要条件,并证明两区间Sturm-Liouville问题的Green函数按特征函数的展开,最后利用Green函数按特征函数的展开证明了修正Parseval等式. 展开更多
关键词 sTURM-LIOUVILLE问题 渐近式 green函数 修正Parseval等式
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S4B-2 Bushen-Yizhi Formula Inhibits the NLRP3/NFκB Mediated Neuroinflammation and Improves the Motor Dysfunction in a Mouse Model of Parkinson’s Disease
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作者 王奇 《神经药理学报》 2018年第4期71-72,共2页
Objective:Parkinson’s disease(PD)is the second largest neurodegenerative disease following Alzheimer’s disease(AD),which associated with aging.There are many similarities in pathology and pathogenesis,even in the TC... Objective:Parkinson’s disease(PD)is the second largest neurodegenerative disease following Alzheimer’s disease(AD),which associated with aging.There are many similarities in pathology and pathogenesis,even in the TCM theory understanding,so we can learn from each other in the process of drug discovery.The clinical results showed that Bushen-Yizhi formula(BSYZ)could effectively improve the neurological function score of senile dementia patients and had a better anti-dementia effect.Further pharmacological studies showed that BSYZ had neuroprotective effects,such as anti-inflammatory,anti-oxidation,anti-apoptosis and neurotrophic effects.In this study,the therapeutic effect of BSYZ on PD was evaluated in vivo and in vivo,and its molecular mechanism was discussed in order to expand the scope of application of BSYZ and to provide strategies for drug discovery of related neurodegenerative diseases.Methods:C57 BL/6 mice were injected intraperitoneally with MPTP to construct a PD mouse model.BSYZ(1.46,2.92,5.84 mg·kg-1)was administered for two weeks,and the positive control group was given a NSAID,piroxicam(12.5 mg·kg-1).After 1 week of pretreatment,MPTP was used to construct a PD mouse model.The mice were subjected to Rotation test on days 1,3 and 5,6th day.and the movement coordination and exercise ability of the drug on PD mice were observed on theThe number of TH-positive cells,Iba1 and CD68-labeled microglial cells in SNpc region were observed by immunofluorescence to observe the proliferation and activation of microglial cells and GFAP-labeled astrocytes.Western blotting was used to detect the nuclear transfer of NLRP3,Caspase-1,ASC,pro-IL-1β,IL-1βand NF-κB in the midbrain.Results:1.BSYZ could significantly improve the expression of MPTP model mice in the experiment of fatigue and Y-maze,increase the number of neurons in SNpc region and the positive expression of TH protein.2.BSYZ significantly inhibited the number of Iba1/CD68-positive microglial cells in MPTP-model mice and decreased the number of GFAP-positive astrocytes.3.BSYZ significantly inhibited the expression of NLRP3-associated protein in BV2 microglial cells induced by LPS+ATP and inhibited the nuclear transfer of NF-κB.Conclusion:BSYZ can effectively relieve the motor dysfunction of PD model mice,improve the damage of dopaminergic neurons,inhibit the proliferation and activation of microglial cells and astrocytes,and have good anti-MPTPinduced neuroinflammation and neuroinflammation mediated by nuclear transfer of NF-κB.The results show that BSYZ has a good prospect of anti-Parkinson’s disease and provides valuable drug discovery strategies for the related neurodegenerative diseases. 展开更多
关键词 Parkinson’s disease Drug Discovery Bushen-Yizhi formula neuroinfl ammation
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Sobolev空间中的Green公式及其应用
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作者 王琳 耿磊 《河南机电高等专科学校学报》 CAS 2008年第2期119-120,共2页
Green公式是数学分析里的一个重要公式,它建立了二重积分与边界曲线积分之间的联系。按照同样的原理,可以把它扩展到Sobolev空间中。文中把数学分析中的Green公式推广到了Sobolev空间中,并给出了几种常用形式及其在变分问题中的应用。
关键词 green公式 sOBOLEV空间 变分问题
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猪德尔塔冠状病毒SYBR Green Ⅰ实时荧光定量PCR方法的建立及应用 被引量:7
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作者 杜倩 汪伟 +7 位作者 韩知晓 孔子荣 辛佳亮 闭璟珊 曹亮 孙文超 胡传活 郑敏 《中国动物传染病学报》 CAS 北大核心 2021年第2期15-21,共7页
为建立一种猪德尔塔病毒(PDCoV)的快速检测方法,本研究根据NCBI公布的PDCoV序列设计了1对特异性引物,利用RT-PCR方法扩增PDCoV的S基因,将其连接至pMD19-T载体上,以构建正确的重组质粒作为标准品,建立SYBR Green Ⅰ实时荧光定量PCR检测方... 为建立一种猪德尔塔病毒(PDCoV)的快速检测方法,本研究根据NCBI公布的PDCoV序列设计了1对特异性引物,利用RT-PCR方法扩增PDCoV的S基因,将其连接至pMD19-T载体上,以构建正确的重组质粒作为标准品,建立SYBR Green Ⅰ实时荧光定量PCR检测方法,并对该方法的敏感性、特异性及重复性进行了验证分析。结果显示:该检测方法在标准品浓度为6.26×10^(1)~6.26×10^(8)copies/μL范围内呈良好线性关系,其相关性为0.999,斜率为-4.312;灵敏度良好,检测下限可达6.26×10^(1)copies/μL;特异性良好,对PEDV和TGEV两种猪常见病原均无特异性扩增;重复性好,组内和组间变异系数均小于2.0%;利用该方法对43份临床样品进行检测,PDCoV阳性率为4.6%。结果表明,本研究成功建立了PDCoV的SYBR GreenⅠ实时荧光定量PCR检测方法,为PDCoV快速灵敏的诊断奠定了坚实基础。 展开更多
关键词 猪德尔塔冠状病毒 s基因 sYBR greenⅠ实时荧光定量PCR
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