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First record of Bystrowianid Chroniosuchians(Amphibia：Anthracosauromorpha) from the Middle Permian of China

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1523-1529页

作者： jiANG Shan ji shu-an MO jinyou natural history museum of guangxi Guangxi 530012China institute of geology chinese academy of geological scienceskey laboratory of stratigraphy and paleontologyministry of land and resourcesBeijing 100037China

Chroniosuchians are basal tetrapods owing to Anthracosauromorpha and the oldest species of chroniosuchians have been recorded in the Late Permian of Russia so far. In this study, we present evidence for their existence in the Middle Permian of China, based on well preserved diagnostic vertebrae with associated osteoderms from the Dashankou fanua in northwestern China. The finds clearly show interosteoderm articulation pattern between the adjacent scutes in bystrowianids. The features observed in Yumenerpeton yangi may warrant the close proximity or phyletic succession of the chroniosuchid and bystrowianid types of the osteoderm design.

关键词： Bystrowianidae Chroniosuchia osteoderms Middle Permian China

EB病毒IgM、IgG及DNA检测在儿童呼吸道感染性疾病中的诊断研究

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中国实用医药 2024年第4期19卷 78-81页

作者：张悦季忠庶申爽葫芦岛市中心医院 125000

目的探析爱泼斯坦-巴尔病毒(EB病毒,EBV)免疫球蛋白(Ig)M、IgG及脱氧核糖核酸(DNA)检测在儿童呼吸道感染性疾病中的诊断价值。方法选取400例呼吸道感染性疾病患儿作为观察组,同时选取100例无呼吸道感染患儿作为对照组。对两组患儿EBV-Ig... 详细信息

目的探析爱泼斯坦-巴尔病毒(EB病毒,EBV)免疫球蛋白(Ig)M、IgG及脱氧核糖核酸(DNA)检测在儿童呼吸道感染性疾病中的诊断价值。方法选取400例呼吸道感染性疾病患儿作为观察组,同时选取100例无呼吸道感染患儿作为对照组。对两组患儿EBV-IgM、EBV-IgG及EBV-DNA进行检测。比较观察组不同年龄段患儿EBV-IgM、EBV-IgG及EBV-DNA阳性率,两组EBV-IgM、EBV-IgG及EBV-DNA检测结果;分析各项指标的诊断价值。结果观察组不同年龄段患儿EBV-IgM、EBV-IgG阳性率比较,差异具有统计学意义(P0.05)。EBV-IgM检测中,观察组化学发光值(11.39±2.12)高于对照组的(9.54±1.35),阳性率50.50%(202/400)高于对照组的5.00%(5/100),差异有统计学意义(P<0.05);EBV-IgG检测中,观察组吸光度值(11.33±2.15)高于对照组的(9.03±1.06),阳性率58.00%(232/400)高于对照组的12.00%(12/100),差异有统计学意义(P<0.05);EBV-DNA检测中,观察组循环数Ct值(34.13±4.88)低于对照组的(43.75±11.62),阳性率57.00%(228/400)高于对照组的6.00%(6/100),差异均具有统计学意义(P<0.05)。EBV-DNA对呼吸道感染性疾病患儿的诊断价值最高[曲线下面积(AUC)=0.644],其次依次是EBV-IgM(AUC=0.618)、EBV-IgG(AUC=0.584),EBV-IgM对呼吸道感染性疾病患儿的诊断特异度最高,为96.12%。结论EBV-IgM、EBV-IgG、EBV-DNA检测在儿童呼吸道感染性疾病的诊断中具有重要的指导意义。

关键词：爱泼斯坦-巴尔病毒免疫球蛋白M 免疫球蛋白G 脱氧核糖核酸儿童呼吸道感染性疾病

A New Giant Compsognathid Dinosaur with Long Filamentous Integuments from Lower Cretaceous of Northeastern China

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Acta Geologica Sinica(English Edition) 2007年第1期81卷 8-15页

作者： ji shu＇ an ji Qiang LU Junchang YUAN Chongxi Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 Key Laboratory of Stratigraphy and Paleontology Chinese Academy of Geological Sciences Beijing 100037

A new compsognathid dinosaur, Sinocalliopteryx gigas gen. et sp. nov., is erected based on a complete skeleton from the Early Cretaceous Yixian Formation of western Liaoning, northeastern China. It shares the features with Huaxiagnathus orientalis in having a manus as long as the humerus plus radius, very large and subequally long manual claws I and H, and reduced olecranon process on the ulna. But it differs from Huaxiagnathus orientalis in having the much large size, a very long maxillary process of premaxilla not extending the vertical level of the maxillary antorbital fossa, and the proportionally longer ulna and so on. Sinocalliopteryx gigas gen. et sp. nov. represents the largest species among the known compsognathid dinosaurs, suggesting the tendency of the body enlargement in compsognathids to some extent. The long filamentous integuments are attached to the whole body of this compsognathid, confirming that such integuments evolved firstly in the basal coelurosaurs. This new giant compsognathid was a fierce carnivorous theropod, as shown further by an incomplete dromaeosaurid leg inside its abdominal cavity.

关键词： Compsognathidae SinocaUiopteryx gen. nov. giant skeleton filamentous integuments,Yixian Formation Early Cretaceous western Liaoning

Fractal Dimension of Random Attractors for Non-autonomous Fractional Stochastic Ginzburg–Landau Equations

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Acta Mathematica Sinica,English Series 2020年第3期36卷 318-336页

作者： Chun Xiao GUO ji shu Xiao Hu WANG Department of Mathematics China University of Mining and Technology BeijingBeijing 100083P.R.China School of Mathematical Science and V.C.&V.R.Key Lab Sichuan Normal UniversityChengdu 610068P.R.China Department of Mathematics Sichuan UniversityChengdu 610064P.R.China

This paper considers the dynamical behavior of solutions for non-autonomous stochastic fractional Ginzburg–Landau equations driven by additive noise with α∈(0, 1). First, we give some conditions for bounding the fractal dimension of a random invariant set of non-autonomous random dynamical system. Second, we derive uniform estimates of solutions and establish the existence and uniqueness of tempered pullback random attractors for the equation in H. At last, we prove the finiteness of fractal dimension of random attractors.

关键词： Non-autonomous stochastic fractional Ginzburg–Landau equation random dynamical system random attractor additive noise fractal dimension

Dynamical behaviors of non-autonomous fractional FitzHugh-Nagumo system driven by additive noise in unbounded domains

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Frontiers of Mathematics in China 2021年第1期16卷 59-93页

作者： Chunxiao GUO Yiju CHEN ji shu Xinguang YANG Department of Mathematics China University of Mining and TechnologyBeijing 100083China Department of Mathematics Sichuan UniversityChengdu 610065China School of Mathematical Science Laurent Mathematics Center and V.C.&:V.R.Key LabSichuan Normal UniversityChengdu 610066China Department of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China

The regularity of random attractors is considered for the non-autonomous fractional stochastic FitzHugh-Nagumo *** prove that the system has a pullback random attractor that is compact in Hs(R^(n))×L^(2)(R^(n))and attracts all tempered random sets of L^(2)(R^(n))×L^(2)(R^(n))in the topology of Hs(R^(n))×L^(2)(R^(n))with s∈(0,1).By the idea of positive and negative truncations,spectral decomposition in bounded domains,and tail estimates,we achieved the desired results.

关键词： Fractional stochastic FitzHugh-Nagumo system random attractor asymptotic compactness

Reclosing Current Limiting for DC Line Faults in VSC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 1040-1049页

作者： shunliang Wang Junjie Zhou ji shu Tianqi Liu Junpeng Ma College of Electrical Engineering Sichuan UniversityChengdu 610065China

The problem of reclosing current limiting in voltage source converter based high-voltage direct current(VSCHVDC)systems is becoming more and more serious.A soft reclosing scheme for DC permanent faults is presented in this *** the converter voltages of stations at both terminals of the disconnected faulty line may be different,the choice of which terminal to reclose first will affect the reclosing overcurrent.A method for selecting the terminal to reclose first is investigated to achieve a minimum peak overcurrent during the reclosing *** order to ensure that the hybrid DC circuit breaker(HDCCB)adapts to the needs of the reclosing process better,the traditional HDCCB is improved by adding a soft reclosing module(SRM).The energy dissipated in the arresters is significantly reduced when using the improved *** improved HDCCB will be able to reclose multiple times safely and thus increase the possibility of successful ***,the recovery time after the HDCCB is successfully reclosed is very short with the improved HDCCB and its control *** results show that this proposed scheme is capable of limiting the reclosing overcurrent when the fault still exists.

关键词： Soft reclosing current limiting voltage source converter based high-voltage direct current(VSC-HVDC) DC fault

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马鞭草苯乙醇苷类成分研究

中成药 2024年第1期46卷 137-142页

作者：李洁董丹阳彭财英杨琴刘建群舒积成江西中医药大学江西南昌330004

目的研究马鞭草Verbenae Herba的苯乙醇苷类成分。方法马鞭草80%乙醇提取物采用硅胶、Sephadex LH-20、TLC、半制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。结果从中分离得到9个化合物,分别鉴定为verbofficoside... 详细信息

目的研究马鞭草Verbenae Herba的苯乙醇苷类成分。方法马鞭草80%乙醇提取物采用硅胶、Sephadex LH-20、TLC、半制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。结果从中分离得到9个化合物,分别鉴定为verbofficoside A(1)、肉苁蓉苷D(2)、广防风苷A(3)、毛蕊花糖苷(4)、异毛蕊花糖苷(5)、肉苁蓉苷C(6)、肉苁蓉苷F(7)、去咖啡酰基毛蕊花苷(8)、jionoside C(9)。结论化合物1为新化合物,化合物3、6~9均首次从该植物中分离得到。

关键词：马鞭草苯乙醇苷分离鉴定

Recognition of Spontaneous Combustion in Coal Mines Based on Genetic Clustering

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Journal of China University of Mining and Technology 2006年第1期16卷 42-45页

作者： SUN ji-ping SONG shu School of Mechanical Electric and Information Engineering China University of Mining ＆ Technology Beijing 100083China

Spontaneous combustion is one of the greatest disasters in coal mines. Early recognition is important because it may be a potential inducement for other coalmine accidents. However, early recognition is difficult because of the complexity of different coal mines. Fuzzy clustering has been proposed to incorporate the uncertainty of spontaneous combustion in coal mines and it can give a clear degree of classification of combustion. Because FCM clustering tends to become trapped in local minima, a new approach of fuzzy c-means clustering based on a genetic algorithm is there- fore proposed. Genetic algorithm is capable of locating optimal or near optimal solutions to difficult problems. It can be applied in many fields without first obtaining detailed knowledge about correlation. It is helpful in improving the effec- tiveness of fuzzy clustering in detecting spontaneous combustion. The effectiveness of the method is demonstrated by means of an experiment.

关键词： coal mine spontaneous combustion fuzzy clustering genetic algorithm

Wong-Zakai approximations and long term behavior of stochastic FitzHugh-Nagumo system

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International Journal of Biomathematics 2021年第3期14卷 23-52页

作者： Ling Qin Dandan Ma ji shu School of Mathematics Science Laurent Mathematics Center and V.C.&V.R.Key Lab Sichuan Normal University Chengdu 610066P.R.China

This paper is concerned with the Wong-Zakai approximations given by a stationary process via the Wiener shift and their associated long term behavior of stochastic FitzHugh-Nagumo system driven by white *** prove the existence and uniqueness of pullback random attractors for the approximate system under much weaker conditions than the original *** the system is driven by additive white noise,we also prove the convergence of solutions of Wong-Zakai approximations and the upper semicontinuity of random attractors of the approximate random system as the size of approximation approaches zero.

关键词： Wong-Zakai approximation random attractor FitzHugh-Nagumo system upper semicontinuity white noise