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Analysis of the ratio of mitchondrial DNA with A1555G mutant to wild type in deaf patients of Fujian province in China by a new method and its relationship with the severity of hearing loss

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Chinese Medical Journal 2011年第20期124卷 3347-3352页

作者： OU Qi-shui CHENG zu-jian yang Bin jianG Ling CHEN Jing Department of Laboratory Medicine First Affiliated HospitalFujian Medical University Fuzhou Fujian 350005 China

Background It has been suggested that the ratio of mutant and wild type mitochondrial DNA may be related to its clinical phenotype. In this study, we developed a high sensitive real-time amplification refractory mutation system-quantitative polymerase chain reaction （RT-ARMS-qPCR） assay for quantitation of the mitochondrial DNA （mtDNA） with a mutated 1555 site, and explored the relationship between the ratio of mutated mtDNA and the severity of hearing loss of mitochondrial deafness （MD） patients of Fujian province in China. Methods An amplified mtDNA fragment containing the 1555 site was ligated into a vector to construct a plasmid DNA standard. An RT-ARMS-qPCR system was used to measure the mtDNA copy number containing wild-type and mutant sequences in a cohort of 126 MD patients of Fujian province in China. Combined with the clinical data, we explored the relationship between the ratio of mutated mtDNA and the severity of hearing loss of MD. Results The variation coefficient in the cohort was 1.21%, the interassay variation coefficient was 1.78%, and the linear range was 102-10e copies/pl for detecting a recombinant, wild-type plasmid. The primers amplified only the intended sequences. Mutation copy number correlated with the degree of deafness in sporadic cases with heteroplasmic mutations of mtDNA A1555G （R=0.811, P=0.003）, but not in sporadic cases with homoplasmic mutations （R=0.007, P=0.989）. The copy number of homoplasmic or heteroplasmic mutations of mtDNA A1555G in familial cases correlated with degree of deafness （R=0.352, P=0.023 and R=0.90, P=0.012, respectively）. Conclusions The RT-ARMS-qPCR system is suitable for determining the copy number of mtDNA fragments containing the A1555G mutation. The ratio of mutated mtDNA correlates with the severity of hearing loss of MD.

关键词： mitochondrial DNA A1555G real time-amplification refractory mutation system-quantitativepolymerase chain reaction deafness

Analysis of Time-domain Electromagnetic Scattering Problem by Multiple Cavities

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 18-48页

作者： yang LIU Yi-xian GAO jian zu School of Mathematics and Statistics and Center for Mathematics and Interdisciplinary SciencesNortheast Normal UniversityChangchunJilin 130024China

The time-domain multiple cavity scattering problem,which arises in diverse scientific areas,has significant industrial and military *** multiple cavities,embedded in an infinite ground plane,is filled with inhomogeneous media characterized by variable dielectric permittivities and magnetic *** to the transverse electric,the scattering problem can be studied by the Helmholtz equation in frequency domain and wave equation in time-domain respectively.A novel transparent boundary condition in time-domain is developed to reformulate the cavity scattering problem into an initial-boundary value problem in a bounded *** well-posedness and stability of the reduced problem are ***,a priori energy estimates for the electric field is obtained with minimum regularity requirement for the data and an explicit dependence on the time by studying the wave equation directly.

关键词： Helmholtz equation wave equation multiple cavities stability a priori estimates

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高速公路改扩建工程边坡防护方案比选分析

西部交通科技 2017年第10期 38-41,72页

作者：王祖坚杨东海段跃华广西桂海高速公路有限公司广西南宁530021

在高速公路边坡施工过程中,设置抗滑支挡结构是处理因施工开挖造成工程滑坡的常用方法。文章结合高速公路改扩建工程边坡实例,对拱形骨架防护、锚杆格梁防护和抗滑桩防护三种防护方案下的边坡稳定性、经济性进行对比分析,确定了采用水... 详细信息

在高速公路边坡施工过程中,设置抗滑支挡结构是处理因施工开挖造成工程滑坡的常用方法。文章结合高速公路改扩建工程边坡实例,对拱形骨架防护、锚杆格梁防护和抗滑桩防护三种防护方案下的边坡稳定性、经济性进行对比分析,确定了采用水磨钻工法成孔的抗滑桩支护形式对该边坡进行加固支护,并介绍了抗滑桩防护的施工工艺。

关键词：高速公路改扩建边坡防护抗滑桩适用性方案比选

Unified Explanation of Quark-Lepton Mass Spectra in q-Deformed Quantum Mechanics

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Chinese Physics Letters 2000年第2期17卷 91-93页

作者： ZHANG jian-zu School of Science East China University of Science and TechnologyShanghai 200237

The quark-lepton mass spectra in q-deformed quantum mechanics are investigated. The theoretical formula of the spectrum includes two new quantum numbers: the q-exciting number n describing generations and the scaling indexes Mi describing families. This formula shows two exponential increases in the mass distribution as generation n increases, the intervals of masses in a given family exponentially increase, and the mass splittings among different members in a generation also exponentially increase. The theoretical values of masses of quarks and leptons reasonably agree with the experimental data except for the electron mass which is one order larger.

关键词： quark exponentially quantum

Influence of Extrusion Joint on Microstructural Evolution and Properties of Mg Alloy Sheet

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Acta Metallurgica Sinica(English Letters) 2016年第5期29卷 475-482页

作者： Qing-Shan yang zu-jian Yu Hu-Cheng Pan Qing-Wei Dai jian-Hui Li School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China Chongqing Academy of Science and Technology Chongqing 401123China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China

The mechanical behaviour of AZ31 magnesium alloy sheet with the extrusion joint （EJ） was evaluated. Extruded joint of AZ31 alloy sheets was obtained by the hot extrusion process. Tensile tests were carried out along the extrusion direction at room temperature, and both the non-uniform plastic deformation and the fracture behaviour were studied. It is found that the samples with EJ present significantly deteriorated mechanical properties compared with the EJ- free counterpart. Inhomogeneous rnicrostructure distribution around EJ zone brings in the uncoordinated deformation due to the high density of {1012} twins which were readily activated during plastic deformation.

关键词： Mg alloy Microstructure Twin Texture Extrusion joint

Simulation and Field Testing of Multiple Vehicles Collision Avoidance Algorithms

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1045-1063页

作者： Chaoyue zu Chao yang jian Wang Wenbin Gao Dongpu Cao Fei-Yue Wang the College of Computer Science and Technology Jilin UniversityChangchun 130012China jiangsu XCMG Construction Machinery Research Institute Ltd. Xuzhou 221004China the College of Computer Science and Technology Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of EducationJilin UniversityChangchun 130012 Chongqing Xibu Automobile Proving Ground Management Co.Ltd. Chongqing 404100China the State Grid JIBEI Electric Power Company Limited Management Training Center China the Advanced Vehicle Engineering Center Cranfield UniversityCranfield MK430ALUK the State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

A global planning algorithm for intelligent vehicles is designed based on the A* algorithm, which provides intelligent vehicles with a global path towards their destinations. A distributed real-time multiple vehicle collision avoidance(MVCA)algorithm is proposed by extending the reciprocal n-body collision avoidance method. MVCA enables the intelligent vehicles to choose their destinations and control inputs independently,without needing to negotiate with each other or with the coordinator. Compared to the centralized trajectory-planning algorithm, MVCA reduces computation costs and greatly improves the robustness of the system. Because the destination of each intelligent vehicle can be regarded as private, which can be protected by MVCA, at the same time MVCA can provide a real-time trajectory planning for intelligent vehicles. Therefore,MVCA can better improve the safety of intelligent vehicles. The simulation was conducted in MATLAB, including crossroads scene simulation and circular exchange position simulation. The results show that MVCA behaves safely and reliably. The effects of latency and packet loss on MVCA are also statistically investigated through theoretically formulating broadcasting process based on one-dimensional Markov chain. The results uncover that the tolerant delay should not exceed the half of deciding cycle of trajectory planning, and shortening the sending interval could alleviate the negative effects caused by the packet loss to an extent. The cases of short delay(< 100100 ms) and low packet loss(< 5%) can bring little influence to those trajectory planning algorithms that only depend on V2 V to sense the context, but the unpredictable collision may occur if the delay and packet loss are further worsened. The MVCA was also tested by a real intelligent vehicle, the test results prove the operability of MVCA.

关键词： Collision avoidance intelligent vehicles intervehicle communication simulation testing trajectory planning

Optimal control approach to stability criteria on Hill's equations

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Applied Mathematics(A Journal of Chinese Universities) 2018年第3期33卷 253-273页

作者： zu jian LI Yong School of Mathematics and Statistics & Center for Mathematics and Interdisciplinary Sciences North-east Normal University Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University College of Mathematics Jilin University

This paper gives a tutorial on how to prove Lyapunov type criteria by optimal control methods. Firstly, we consider stability criteria on Hill’s equations with nonnegative potential. By optimal control methods developed in 1990s, we obtain several stability criteria including Lyapunov’s criterion, Neǐgauz and Lidskiǐ’s criterion. Secondly, we present stability criteria on Hill’s equations with sign-changing potential in which Brog’s criterion and Krein’s criterion are included.

关键词： stability criteria optimal control method Hill's equation Lyapunov inequality

用膦酰化试剂[o-ethyl-s-(diisopropylaminoethyl-2)methanethiophosphonate]滴定乙酰胆碱酯酶的活性中心

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Acta Biochimica et Biophysica Sinica 1984年第6期 586-591页

作者：张祖传杨建中张振范曹蕙婷中国科学院上海生物化学研究所

用稳定的乙酰胆碱酯酶不可逆抑制剂（MTP）滴定了猪脑尾核、眼镜蛇蛇毒和电鳗电组织乙酰胆碱酯酶溶液的活性中心数。抑制剂与这些酶的二级反应常数分别为:1.69×105l·mol-1·s-1;6.72×105l·mol-1·s-1和6.78×105l·mol-1·s-1。因为... 详细信息

用稳定的乙酰胆碱酯酶不可逆抑制剂（MTP）滴定了猪脑尾核、眼镜蛇蛇毒和电鳗电组织乙酰胆碱酯酶溶液的活性中心数。抑制剂与这些酶的二级反应常数分别为:1.69×105l·mol-1·s-1;6.72×105l·mol-1·s-1和6.78×105l·mol-1·s-1。因为MTP膦酰化的紫贻贝血淋巴液乙酰胆碱酯酶容易自活化,故此法不能用来滴定这种酶的活性中心。

关键词：电鳗电器官眼镜蛇蛇毒尾核猪脑 diisopropylaminoethyl-2)methanethiophosphonate o-ethyl-s 活性中心乙酰胆碱酯酶真性胆碱酯酶乙酸胆碱自活化滴定

Softening–melting behavior of mixed burden based on low-magnesium sinter and fluxed pellets

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 621-628页

作者： Gui-lin Wang jian Kang jian-liang Zhang Yao-zu Wang Zhi-yu Wang Zheng-jian Liu Chen-yang Xu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Chemical Engineering The University of QueenslandSt LuciaQLD 4072Australia Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China Baosteel Zhanjiang Iron and Steel Co. Ltd.Zhanjiang 524072China

A low MgO content in sinter is conducive to reduce the MgO content in blast furnace *** study investigated the effect of MgO content in sinter on the softening–melting behavior of the mixed burden based on fluxed *** the MgO content increased from 1.31 wt% to 1.55 wt%, the melting temperature of sinter increased to 1521℃.Such an increase was due to the formation of the high-meltingpoint slag *** reduction degradation index of sinter with 1.31 wt% MgO content was better than that of *** initial softening temperature of the mixed burden increased from 1104 to 1126℃ as MgO content in sinter increased from 1.31 wt% to 1.55 wt%, and the melting temperature decreased from 1494 to 1460℃.The permeability index(S-value) of mixed burden decreased to 594.46 kPa·℃ under a high MgO content with 1.55 wt%, indicating that the permeability was *** slag phase composition of burden was mainly akermarite(Ca_(2)MgSiO_(7)) when the MgO content in sinter was 1.55 wt%.The melting point of akermarite is 1450℃, which is lower than other phases.

关键词： magnesia softening–melting behavior low-magnesium sinter fluxed pellets slag