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Branch Processes of Vortex Filaments and Hopf Invariant Constraint on Scroll Wave

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Communications in Theoretical Physics 2009年第12期52卷 1149-1156页

作者： ZHU Tao REN ji-Rong MO shu-Fan Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper, by making use of Duan＇s topological current theory, the evolution of the vortex filaments in excitable media is discussed in detail. The vortex filaments are found generating or annihilating at the limit points and encountering, splitting, or merging at the bifurcation points of a complex function Z（x, t）. [t is also shown that the Hopf invariant of knotted scroll wave filaments is preserved in the branch processes （splitting, merging, or encountering） during the evolution of these knotted scroll wave filaments. Furthermore, it also revealed that the ＂exclusion principle＂ in some chemical media is just the special case of the Hopf invariant constraint, and during the branch processes the ＂exclusion principle＂ is also protected by topology.

关键词： scroll wave Hopf invariant topology of knot vortex filament

循环肿瘤细胞联合血清标志物检测对胃癌患者术后复发的预测价值

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实用中西医结合临床 2024年第14期24卷 4-6,57页

作者：姬汉书王鹏顾小红河北省沧州市中心医院沧州061001 华北医疗健康集团峰峰总医院河北邯郸056200 河北省廊坊市人民医院廊坊065099

目的循环肿瘤细胞(CTCs)联合血清标志物(STM)检测对胃癌患者术后复发的预测价值。方法选取2020年6月至2021年12月沧州市中心医院收治的80例胃癌手术患者为研究对象,根据术后复发情况分为对照组(n=51,术后未复发)和观察组(n=29,术后复发)... 详细信息

目的循环肿瘤细胞(CTCs)联合血清标志物(STM)检测对胃癌患者术后复发的预测价值。方法选取2020年6月至2021年12月沧州市中心医院收治的80例胃癌手术患者为研究对象,根据术后复发情况分为对照组(n=51,术后未复发)和观察组(n=29,术后复发),比较两组患者CTCs、STM检测情况,并通过绘制受试者工作特征(ROC)曲线分析CTCs联合STM检测对胃癌患者术后复发的预测价值。结果观察组癌胚抗原(CEA)、胃癌抗原724(CA724)、糖类抗原199(CA199)含量及CTCs数量均显著高于对照组(P<0.05);观察组CEA阳性检出率、CA724阳性检出率、CA199阳性检出率、CTCs阳性检出率均高于对照组(P<0.05);绘制ROC曲线发现,CEA、CA724、CA199、CTCs检测及联合预测胃癌患者术后复发的曲线下面积(AUC)为0.683~0.754,灵敏度和特异度均较高。结论CTCs联合STM(CEA、CA199、CA724)检测可显著提高胃癌患者术后复发早期诊断准确性,在预测胃癌术后复发方面具有一定的评估效能。

关键词：胃癌复发循环肿瘤细胞血清标志物预测价值

New Material of Sinosauropteryx (Theropoda:Compsognathidae) from Western Liaoning,China

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Acta Geologica Sinica(English Edition) 2007年第2期81卷 177-182页

作者： ji shu＇an GAO Chunling LIU jinyuan MENG Qingjin ji Qiang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 Dalian Natural History Museum Dalian Liaoning 116023

An incomplete specimen of Sinosauropteryx prima collected from the Early Cretaceous Yixian Formation of the Dawangzhangzi area in Lingyuan, western Liaoning is depicted. It represents the first systematically described material of this feathered compsognathid outside the Sihetun area in Beipiao. This specimen shows some diagnostic features of Sinosauropteryx prima, such as the very short forelimb in relation to hindlimb with the length ratio of humerus plus radius to femur plus tibia just around 30%, and the long and massive first manual ungual subequal in length to radius. The presence of Sinosauropteryx prima only at Sihetun and Dawangzhangzi supports the suggestion that the fossil-bearing beds in the Sihetun and Dawangzhangzi areas are equivalent to each other within the Yixian Formation.

关键词： Sinosauropteryx Lingyuan Liaoning Yixian Formation stratigraphic correlation,Cretaceous

一类带加性噪声的随机偏微分方程在不同相空间中的中心流形

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四川师范大学学报（自然科学版） 2024年第4期47卷 555-561页

作者：龚佳鑫吴隆钰杨娟舒级四川师范大学数学科学学院四川成都610066 四川师范大学可视化计算与虚拟现实四川省重点实验室四川成都610066

研究一类带加性噪声的随机偏微分方程在不同相空间中的中心流形的存在性.通过引入随机变换的方法处理噪声项,得到随机偏微分方程的解,生成随机动力系统,再通过Lyapunov-Perron方法证明中心流形的存在性.

关键词：随机偏微分方程随机动力系统随机中心流形加性噪声

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一类具有乘性噪声的时滞随机演化方程的随机中心流形的存在性与光滑性

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四川师范大学学报（自然科学版） 2024年第5期47卷 696-707页

作者：杨娟龚佳鑫吴隆钰舒级四川师范大学数学科学学院四川成都610066 四川师范大学可视化计算与虚拟现实四川省重点实验室四川成都610066

研究一类具有乘性噪声的时滞随机演化方程的随机中心流形的存在性与光滑性.由于时滞的影响,首先对带时滞的非线性项进行转化并处理由时滞影响产生的系数,从而得到中心流形的存在性,然后利用Lyapunov-Perron方法证明方程的中心流形的光滑性.

关键词：时滞随机演化方程随机中心流形乘性噪声存在性光滑性

The First Discovery of the Late Cretaceous Protoceratopsid Fauna from Alxa, Inner Mongolia, China

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1908-1909页

作者： ji shu'an ZHANG Lifu LU Liwu HAO jianqiang Institute of Geology Chinese Academy of Geological Sciencest Beijing 100037 China Administration of the Otog Dinosaur Trace National Nature Reserve Otog Qi 016100 Inner Mongolia China The Geological Museum of China Beijing 100034 China Inner Mongolia General Team China Building Material Geology Investigation Center Huhhot 010011 Inner Mongolia China

Objective Alxa,located in western Inner Mongolia,is covered by desert in many places with few Cretaceous *** some Early Cretaceous dinosaur fossils have been discovered from several areas in Alxa Zuoqi and Ejin Qi,but... 详细信息

关键词： China Inner Mongolia The First Discovery of the Late Cretaceous Protoceratopsid Fauna from Alxa

Observed deformation characteristics of a deep excavation for the spring area in jinan,China

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Journal of Mountain Science 2017年第3期14卷 581-594页

作者： ZHANG Ding-wen shu ji-cheng SUN jian-ping Institute of Geotechnical Engineering School of TransportutionSoutheast UniversityNanjing 210096China School ofCivilEngineering ShangdongJianzhu UniversityJinan 250014China

The observed deflections and internal forces of pile-anchor retaining excavation were studied in spring area in jinan city of China. Based on field measured data, the ground surface settlement, deflection of retaining piles and wall, internal force analysis of concrete piles, axial anchoring forces, groundwater table, and the deformation of surround building and pipelines were investigated. The results indicates that the combining application of concrete piles, jet grouting columns and anchors support system can effectively control excavation-induced surface ground settlements. The field maximum lateral wall deflections are between 0.o2% and o.19% of the excavation depth due to the competitive site conditions. The bending moment-depth relationship curve is S-type. Groundwater leakage results in the sharp drop in groundwater level, which is part of the reasons for the adjacent building settlement. The axial anchoring forces of the upper layer of anchors increase gradually during the excavation, but those of the lower layer of anchors slightly reduced firstly and then tend to be stable during the excavation procedure. In comparison with the histories of excavation cases, the small lateral wall deflection in this study results from the favorable site condition and the relative rigidity of the retaining structure system.

关键词： Spring area Excavation Pile anchor system Ground settlement Horizontal displacement

SEM Observation of the Wing Membrane of Beipiaopterus chenianus (Pterosauria)

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Acta Geologica Sinica(English Edition) 2005年第6期79卷 766-769页

作者： LU Junchang KOBAYASHI Yoshitsugu YUAN Chongxi ji shu＇an ji Qiang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Hokkaido University Museum Hokkaido UniversityN10 W8 Kita Ku Sapporo Hokkaido 060-0810 Japan

The cross-section and surface structures of wing membranes from the ctenochasmatid pterosaur Beipiaopterus chenianus were observed through a scanning electron microscope （SEM）. The results show that the wing membrane contains a high density of blood vessels, implying strong thermoregulatory function, similar to that of a bat wing membrane. This is the first comparison of the microstmctures of pterosaur wing membranes with those of the modem bat. It is inferred that a bat-like physiology exists, at least in relatively small pterosaurs suggesting that these pterosaurs were warm-blooded, active fliers.

关键词： Beipiaopterus wing membrane microstructures SEM

Cokriging of Soil Cation Exchange Capacity Using the First Principal Component Derived from Soil Physico-Chemical Properties

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Agricultural Sciences in China 2011年第8期10卷 1246-1253页

作者： LIAO Kai-hua XU Shao-hui WU ji-chun ji shu-hua LIN Qing Department of Hydrosciences Nanjing UniversityNanjing 210093P.R.China Department of Environmental Science Qingdao UniversityQingdao 266071P.R.China

As soil cation exchange capacity （CEC） is a vital indicator of soil quality and pollutant sequestration capacity,a study was conducted to evaluate cokriging of CEC with the principal components derived from soil physico-chemical *** Qingdao,China,107 soil samples were *** CEC was estimated by using 86 soil samples for prediction and 21 soil samples for *** first two principal components （PC1 and PC2） together explained 60.2% of the total variance of soil physico-chemical *** PC1 was highly correlated with CEC （r=0.76,P0.01）,whereas there was no significant correlation between CEC and PC2 （r=0.03）.The PC1 was then used as an auxiliary variable for the prediction of soil *** error （ME） and root mean square error （RMSE） of kriging for the test dataset were-1.76 and 3.67 cmolc kg-1,and ME and RMSE of cokriging for the test dataset were-1.47 and 2.95 cmolc kg-1,*** cross-validation R2 for the prediction dataset was 0.24 for kriging and 0.39 for *** results show that cokriging with PC1 is more reliable than kriging for spatial *** addition,principal components have the highest potential for cokriging predictions when the principal components have good correlations with the primary variables.

关键词： soil cation exchange capacity spatial interpolation root mean square error geostatistics