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Advances in Applied Mathematics and Mechanics 2022年第3期14卷 759-776页

作者： Shuainan Liu Zhuojia Fu yan gu Center for Numerical Simulation Software in Engineering and Sciences College of Mechanics and MaterialsHohai UniversityNanjingJiangsu 211100China School of Mathematics and Statistics Qingdao UniversityQingdaoShandong 266071China

The localized method of fundamental solutions(LMFS)is a relatively new meshless boundary collocation *** the LMFS,the global MFS approxima-tion which is expensive to evaluate is replaced by local MFS formulation deﬁned in a set of overlapping *** LMFS algorithm therefore converts differential equations into sparse rather than dense matrices which are much cheaper to *** paper makes theﬁrst attempt to apply the LMFS,in conjunction with a domain-decomposition technique,for the numerical solution of steady-state heat con-duction problems in two-dimensional(2D)anisotropic layered ***,the layered material is decomposed into several subdomains along the layer-layer inter-faces,and in each of the subdomains,the solution is approximated by using the LMFS *** the subdomain interface,compatibility of temperatures and heatﬂuxes are *** numerical experiments illustrate that the proposed domain-decomposition LMFS algorithm is accurate,stable and computationally efﬁcient for the numerical solution of large-scale multi-layered materials.

关键词： Meshless method localized method of fundamental solutions heat conduction prob-lems layered materials large-scale problems

Integrating Krylov Deferred Correction and Generalized Finite Difference Methods for Dynamic Simulations of Wave Propagation Phenomena in Long-Time Intervals

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Advances in Applied Mathematics and Mechanics 2021年第6期13卷 1398-1417页

作者： Wenzhen Qu Hongwei Gao yan gu School of Mathematics and Statistics Qingdao UniversityQingdaoShandong 266071China Institute of Mechanics for Multifunctional Materials and Structures Qingdao UniversityQingdaoShandong 266071China

In this paper,a high-accuracy numerical scheme is developed for long-time dynamic simulations of 2D and 3D wave propagation *** the derivation of the present approach,the second order time derivative of the physical quantity in the wave equation is treated as a substitution *** on the temporal discretization with the Krylov deferred correction(KDC)technique,the original wave problem is then converted into the modified Helmholtz *** transformed boundary value problem(BVP)in space is efficiently simulated by using the meshless generalized finite difference method(GFDM)with Taylor series after truncating the second and fourth order *** developed scheme is finally verified by four numerical experiments including cases with complicated domains or the temporally piecewise defined source *** results match with the analytical solutions and results by the COMSOL software,which demonstrates that the developed KDC-GFDM can allow large time-step sizes for wave propagation problems in longtime intervals.

关键词： Wave equation Krylov deferred correction technique large time-step long-time simulation,generalized finite difference method

On Hilbert Coefficients of Filtrations

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Chinese Annals of Mathematics,Series B 2007年第5期28卷 543-554页

作者： yan gu guangjun ZHU Zhongming TANG Department of Mathematics Suzhou University Suzhou 215006 Jiangsu China.

Let F be a Hilbert filtration with respect to a Cohen-Macaulay module M. When G（F, M） and FK（F,M） have almost maximal depths, the Hilbert coefficients gi（F, M） is calculated. In the general case, an upper bound ... 详细信息

关键词： Hilbert coefficients Fiber cones Depth

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均质土坝管涌溃决实验渗流分析

中国农村水利水电 2024年第6期 166-173页

作者：刘宪东谷艳昌王士军陆强王宏南京水利科学研究院大坝安全与管理研究所江苏南京210029 水利部大坝安全管理中心江苏南京210029

管涌渗漏破坏是导致土石坝溃决的主要原因之一,通过模型实验开展土石坝管涌过程渗流场变化研究,对土石坝安全预测预警具有重要意义。采用预设管涌通道模拟管涌渗漏的方式,建立了室内小尺寸均质土坝管涌溃决模型;通过布置小量程渗压计,... 详细信息

管涌渗漏破坏是导致土石坝溃决的主要原因之一,通过模型实验开展土石坝管涌过程渗流场变化研究,对土石坝安全预测预警具有重要意义。采用预设管涌通道模拟管涌渗漏的方式,建立了室内小尺寸均质土坝管涌溃决模型;通过布置小量程渗压计,获取土坝模型的渗流场数据,对土坝模型从蓄水到渗透破坏再到溃决全过程的渗流场变化进行了深入分析研究。分析发现,在蓄水阶段,相同轴距的管涌断面测点渗流压力小于非管涌断面测点的测值,但测值达到峰值的时间早于非管涌断面测点;在溃决阶段(出现明流和形成溃口阶段),坝体内渗流压力出现骤降,且越靠近管涌断面渗流压力骤降时间越早、骤降幅度也越大。该认识,对于土石坝管涌渗漏破坏预测预警提供借鉴。

关键词：土石坝管涌溃决模型实验渗流分析预测预警

盐酸氨溴索对脂多糖诱导急性肺损伤大鼠肺血管重塑的改善作用及机制

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中国老年学杂志 2024年第5期44卷 1112-1118页

作者：饶习敏顾延会刘晓丽张兰英欧阳瑶遵义医科大学附属医院呼吸与危重症学科贵州遵义563000

目的探讨盐酸氨溴索对脂多糖(LPS)诱导急性肺损伤(ALI)大鼠肺血管重塑的作用及机制。方法选取80只SD大鼠,按照随机数字表法分为正常组、模型组、实验(盐酸氨溴索处理ALI)组、阳性[阳性对照药地塞米松(DXMS)处理]组各20只。除正常组外... 详细信息

目的探讨盐酸氨溴索对脂多糖(LPS)诱导急性肺损伤(ALI)大鼠肺血管重塑的作用及机制。方法选取80只SD大鼠,按照随机数字表法分为正常组、模型组、实验(盐酸氨溴索处理ALI)组、阳性[阳性对照药地塞米松(DXMS)处理]组各20只。除正常组外,其余组采用LPS构建ALI大鼠模型。术后第2天起每日分别在实验组和阳性组皮下注射1 ml、规格为20 mg/kg的盐酸氨溴索和DXMS,连续给药28 d,正常组和模型组每日注射等量生理盐水,连续注射28 d。实验流程结束后,采用苏木素-伊红(HE)染色检测病理组织,弹力纤维(EVG)染色检测血管重塑情况,TUNEL染色检测肺动脉平滑肌细胞凋亡情况,免疫组化染色检测α-平滑肌肌动蛋白(SMA)和血管内皮生长因子(VEGF)表达,线粒体膜电位试剂盒(JC-1)检测线粒体膜电位。结果模型组肺小动脉中膜厚度大于正常组,血管肌化程度、肺动脉平滑肌细胞凋亡率高于正常组,肺组织中α-SMA、VEGF、线粒体膜电位、胱天蛋白酶(Caspase)-3、B细胞淋巴瘤(Bcl)-2相关X蛋白(Bax)表达高于正常组,Bcl-2表达低于正常组,差异均具有统计学意义(均P<0.05);实验组和阳性组肺小动脉中膜厚度小于模型组,血管肌化程度、肺动脉平滑肌细胞凋亡率低于模型组,肺组织中α-SMA和VEGF、线粒体膜电位、Caspase-3、Bax蛋白表达低于模型组,Bcl-2蛋白表达高于模型组,差异均具有统计学意义(P<0.05)。结论肺平滑肌细胞可通过盐酸氨溴索降低凋亡率并对其血管重塑有改善作用,进而减少ALI肺组织损伤。

关键词：盐酸氨溴索肺损伤平滑肌细胞凋亡血管重塑

Impact of GCP distribution on the rectification accuracy of Landsat TM imagery in a coastal zone

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Acta Oceanologica Sinica 2006年第4期25卷 14-22页

作者： ZHANG Ying ZHANG Dong gu yan TAO Fei College of Geographic Sciences Nanjing Normal University Nanjing 2113097 China Telecommunication Engineering Department Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

The purpose is to explore the effect of the spatial distribution of ground control points （GCPs） on the accuracy of imagery rectification. Both area-distributed and linearly distributed GCPs were used to rectify a Landsat TM image of a coastal zone. Rectification accuracy was checked against 99 independent points over the intertidal mudflats with no ground control. Results indicate that the root-mean-square error of residuals over these areas is several times larger than its GCPs-measured counterpart. If the GCPs are spatially dispersed over an area, residuals fluctuate but increase steadily with distance to the source of control in easting （R^2= 0. 827）. in northing they fluctuate around 150 m until 15 km, beyond which they rise steadily at a small range of fluctuation. These residuals are less predictable from distance to the source of control than in easting （R^2= 0.517 ）. If the GCPs are distributed along a control line, residuals rise with distance to it linearly and predictably （R^2 = 0. 877） in the direction perpendicular to it. In a direction parallel to it, the distance has little impact on rectification residuals.

关键词： image rectification ground control point rectification residuals coastal zone

YTHDC1介导的CENPK调节人宫颈癌细胞侵袭和增殖

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皖南医学院学报 2024年第1期43卷 19-23页

作者：顾艳赵夏丽王梅倪观太皖南医学院第一附属医院弋矶山医院妇产科安徽芜湖241001

目的:找寻宫颈癌的预测、治疗靶点,探究靶点与N6-甲基腺苷(m6A)核酸修饰之间的联系及发挥的生物学功能。方法:在GEPIA2数据库提供的数据中筛选宫颈癌差异表达的基因。EdU实验、划痕实验以及Transwell实验分别检测着丝粒蛋白K(CENPK)对... 详细信息

目的:找寻宫颈癌的预测、治疗靶点,探究靶点与N6-甲基腺苷(m6A)核酸修饰之间的联系及发挥的生物学功能。方法:在GEPIA2数据库提供的数据中筛选宫颈癌差异表达的基因。EdU实验、划痕实验以及Transwell实验分别检测着丝粒蛋白K(CENPK)对宫颈癌细胞增殖、迁移和侵袭能力的影响。RNA m6A修饰的定量测定结合蛋白质印迹法研究m6A修饰与CENPK高表达的关系。结果:CENPK在宫颈癌组织中上调(P<0.05)。沉默CENPK基因导致宫颈癌细胞增殖能力下降,抑制了细胞迁移和侵袭(P<0.01)。m6A阅读器YTH域包含蛋白1(YTHDC1)通过降低CENPK蛋白的表达在宫颈癌细胞中发挥作用(P<0.01)。结论:CENPK可能是一个潜在的宫颈癌治疗靶点。

关键词：宫颈癌着丝粒蛋白K YTH域包含蛋白1 肿瘤细胞侵袭增殖

基于CTA评价颈动脉斑块易损性与分布位置之间的相关性

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中国医学工程 2024年第1期32卷 7-12页

作者：赵艺楠顾艳刘颖郭中萍锦州医科大学(连云港市第一人民医院)研究生培养基地辽宁锦州121000 连云港市第一人民医院医学影像科江苏连云港222000 南京医科大学(连云港市第一人民医院)研究生培养基地江苏南京211166

目的利用CTA分析颈动脉斑块分布位置、特征与斑块易损性的关系,为颈动脉粥样斑块的危险因素及形成机制提供更多信息。方法选取2020年10月至2021年10月连云港市第一人民医院收治的颈动脉粥样硬化患者且伴有短暂性脑缺血症状共89例。从... 详细信息

目的利用CTA分析颈动脉斑块分布位置、特征与斑块易损性的关系,为颈动脉粥样斑块的危险因素及形成机制提供更多信息。方法选取2020年10月至2021年10月连云港市第一人民医院收治的颈动脉粥样硬化患者且伴有短暂性脑缺血症状共89例。从CTA轴位测量颈动脉分叉处斑块的特征参数(斑块厚度、长度、最大横截面积、斑块负荷和重塑指数)和斑块分布位置,根据斑块是否具有高危特征(包括斑块内出血、富含脂质的坏死核心、斑块溃疡等),将斑块分为高危组和低危组,分析两组斑块的特征与分布位置的差异。结果根据斑块高危特征,144条颈动脉中高危组79条,低危组65条。两组间的斑块厚度、长度、最大横截面积、斑块负荷、斑块分布差异有统计学意义(P0.05)。结论高危斑块好发于颈动脉分叉处的背侧,且颈动脉分叉处斑块的厚度、横断面积及斑块负荷越大,斑块越倾向于不稳定,而低危斑块倾向于发生在颈动脉分叉外侧。

关键词：缺血性卒中斑块易损性动脉粥样硬化斑块分布颈动脉斑块

Evolving strategies for tumor immunotherapy:enhancing the enhancer and suppressing the suppressor

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National Science Review 2017年第2期4卷 161-163页

作者： yan gu yanfang Liu Xuetao Cao National Key Laboratory of Medical Immunology & Institute of Immunology Second Military Medical University Department of Pathology Changhai HospitalSecond Military Medical University Department of Immunology & Center for Immunotherapy Institute of Basic Medical SciencesPeking Union Medical CollegeChinese Academy of Medical Sciences

Cancers develop complex and dynamic tissue microenvironments to support their sustained growth,invasion and *** decades,rapid progress has been made in the cross talk between tumor cells and the surrounding microenvir... 详细信息

关键词： cell MDSC Evolving strategies for tumor immunotherapy:enhancing the enhancer and suppressing the suppressor

Localized Method of Fundamental Solutions for Three-Dimensional Elasticity Problems: Theory

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Advances in Applied Mathematics and Mechanics 2021年第6期13卷 1520-1534页

作者： yan gu Chia-Ming Fan Zhuojia Fu School of Mathematics and Statistics Qingdao UniversityQingdaoShandong 266071China Department of Civil Engineering University of SiegenPaul-Bonatz-Str.9-11D-57076 SiegenGermany Department of Harbor and River Engineering&Computation and Simulation Center Taiwan Ocean UniversityKeelung 20224Taiwan Center for Numerical Simulation Software in Engineering and Sciences College of Mechanics and MaterialsHohai UniversityNanjingJiangsu 211100China

A localized version of the method of fundamental solution(LMFS)is devised in this paper for the numerical solutions of three-dimensional(3D)elasticity *** present method combines the advantages of high computational efficiency of localized discretization schemes and the pseudo-spectral convergence rate of the classical MFS *** a combination will be an important improvement to the classical MFS for complicated and large-scale engineering *** examples with up to 100,000 unknowns can be solved without any difficulty on a personal computer using the developed *** advantages,disadvantages and potential applications of the proposed method,as compared with the classical MFS and boundary element method(BEM),are discussed.

关键词： Method of fundamental solutions meshless method large-scale simulations elasticity problems.