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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOssEINI O.BALILAshAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： stress concentration

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Unlocking the future:Mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

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World Journal of Clinical Oncology 2025年第1期16卷 43-52页

作者： Zhi-Jian tang Yuan-Ming Pan Wei Li Rui-Qiong Ma Jian-Liu Wang Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China Cancer Research Center Beijing Chest HospitalBeijing 101149China Department of Thoracic surgery Sichuan Provincial People's HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Mitochondrial genes are involved in tumor metabolism in ovarian cancer(OC)and affect immune cell infiltration and treatment *** To predict prognosis and immunotherapy response in patients diagnosed with OC using mitochondrial genes and neural *** Prognosis,immunotherapy efficacy,and next-generation sequencing data of patients with OC were downloaded from The Cancer Genome Atlas and Gene Expression *** genes were sourced from the MitoCarta3.0 *** discovery cohort for model construction was created from 70% of the patients,whereas the remaining 30% constituted the validation *** the expression of mitochondrial genes as the predictor variable and based on neural network algorithm,the overall survival time and immunotherapy efficacy(complete or partial response)of patients were *** In total,375 patients with OC were included to construct the prognostic model,and 26 patients were included to construct the immune efficacy *** average area under the receiver operating characteristic curve of the prognostic model was 0.7268[95% confidence interval(CI):0.7258-0.7278]in the discovery cohort and 0.6475(95%CI:0.6466-0.6484)in the validation *** average area under the receiver operating characteristic curve of the immunotherapy efficacy model was 0.9444(95%CI:0.8333-1.0000)in the discovery cohort and 0.9167(95%CI:0.6667-1.0000)in the validation *** The application of mitochondrial genes and neural networks has the potential to predict prognosis and immunotherapy response in patients with OC,providing valuable insights into personalized treatment strategies.

关键词： Ovarian cancer Mitochondria Prognosis Immunotherapy Neural network

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A novel mesh-free poly-cell Galerkin method

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Acta Mechanica sinica 2009年第4期25卷 517-527页

作者： C. Zheng X. h. tang J. h. Zhang s. C. Wu state Key Laboratory of hydraulics and Mountain River Engineering Sichuan University state Key Laboratory of Digital Manufacturing and Equipment Technology Huazhong University of Science and Technology Centre for Advanced Computations in Engineering science (ACEs) Department of Mechanical EngineeringNational University of Singapore

A novel numerical method is explored and named as mesh-free poly-cell Galerkin method. An improved moving least-square （MLs） scheme is presented, which can avoid the matrix inversion in standard MLs and can be used to construct shape functions possessing delta Kronecher property. A new type of local support is introduced to ensure the alignment of integral domains with the cells of the back-ground mesh, which will reduce the difficult in integration. An intensive numerical study is conducted to test the accuracy of the present method. It is observed that solutions with good accuracy can be obtained with the present method.

关键词： MPG CO-MsL Mesh-free Meshless Voronoi diagram

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A novel twice-interpolation finite element method for solid mechanics problems

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Acta Mechanica sinica 2010年第2期26卷 265-278页

作者： C. Zheng s. C. Wu X. h. tang J. h. Zhang state Key Laboratory of hydraulics and Mountain River Engineering Sichuan University 610065 Chengdu China state Key Laboratory of Digital Manufacturing and Equipment Technology Huazhong University of Science and Technology 430074 Wuhan China Department of Mechanical Engineering Centre for Advanced Computations in Engineering Science (ACES)National University of Singapore Singapore 117576 Singapore

Formulation and numerical evaluation of a novel twice-interpolation finite element method （TFEM） is presented for solid mechanics problems. In this method, the trial function for Galerkin weak form is constructed through two stages of consecutive interpolation. The primary interpolation follows exactly the same procedure of standard FEM and is further reproduced according to both nodal values and averaged nodal gradients obtained from primary interpolation. The trial functions thus constructed have continuous nodal gradients and contain higher order polynomial without increasing total freedoms. several benchmark examples and a real dam problem are used to examine the TFEM in terms of accuracy and convergence. Compared with standard FEM, TFEM can achieve significantly better accuracy and higher convergence rate, and the continuous nodal stress can be obtained without any smoothing operation. It is also found that TFEM is insensitive to the quality of the elemental mesh. In addition, the present TFEM can treat the incompressible material without any modification.

关键词： Twice-interpolation finite element method·stress smoothing Volumetric locking Mesh distortion

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阿尔茨海默病NK细胞与铜死亡的相关基因分析

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中国组织工程研究 2025年第19期29卷 4172-4180页

作者：陈桂琳汤其强安徽医科大学附属省立医院神经内科安徽省合肥市230001

背景:阿尔茨海默病的免疫相关致病机制尚不明确,通过生物信息学探讨阿尔茨海默病患者NK细胞与铜死亡机制的相关性,可为研究阿尔茨海默病的发生发展提供新方向。目的:使用生物信息学分析方法筛选阿尔茨海默病患者外周血中NK细胞与铜死亡... 详细信息

背景:阿尔茨海默病的免疫相关致病机制尚不明确,通过生物信息学探讨阿尔茨海默病患者NK细胞与铜死亡机制的相关性,可为研究阿尔茨海默病的发生发展提供新方向。目的:使用生物信息学分析方法筛选阿尔茨海默病患者外周血中NK细胞与铜死亡相关的关键基因,并在临床标本水平加以验证。方法:利用GEO在线数据库筛选阿尔茨海默病患者外周血转录组差异表达基因和NK细胞相关基因,与已报告的铜死亡因子取交集,获取差异表达的铜死亡相关基因;接着采用RT-qPCR技术对基因相对表达量进行实验验证,实验样本来自于安徽省立医院神经内科2021-2023年住院患者的外周血,按照纳排标准纳入疾病组30例及对照组20例。后续进一步使用在线GeneMANIA网站构建蛋白质-蛋白质互作网络;利用R语言进行免疫浸润分析;基于ENCODE数据库进行转录因子预测。结果与结论:①利用GsE63060数据集中阿尔茨海默病患者外周血转录组差异表达基因、GsE168522数据集中NK细胞相关基因、已报告的铜死亡基因,应用在线韦恩图工具、LAssO算法及随机森林机器学习方法筛选获取4个差异表达的铜死亡相关基因:铁氧还原蛋白1(ferredoxin 1,FDX1)、铜离子转运ATP酶a肽(ATPase Cu^(2+)transporting alpha polypeptide,ATP7A)、丙酮酸脱氢酶β(pyruvate dehydrogenase El subunit beta,PDhB)和二氢硫辛酰胺琥珀酰转移酶(dihydrolipoamide succinyltransferase,DLsT)。②临床样本实验验证,FDX1和ATP7A在阿尔茨海默病患者外周血中表达上调(PhB和DLsT在阿尔茨海默病患者外周血中表达下调(P0.05)。③蛋白质-蛋白质互作网络发现20种功能蛋白与关键基因相关联,免疫浸润分析结果验证了关键基因与12个免疫细胞具有显著相关性(以PhB和DLsT基因在阿尔茨海默病中存在差异性表达,这4个基因在阿尔茨海默病外周血的NK细胞中可能通过铜死亡机制参与了疾病的发生发展,文章结果为阿尔茨海默病的诊断及治疗提供了潜在的靶点。

关键词：阿尔茨海默病生物信息学 NK细胞铜死亡 FDX1 ATP7A PDhB DLsT

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structural and magnetic properties of sm(Co_(0.7)Fe_(0.1)Ni_(0.12)Zr_(0.04)B_(0.04))_(7.5) melt spun isotropic and anisotropic ribbons

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Journal of Rare Earths 2012年第7期30卷 691-695页

作者： sofoklis s. Makridis Wei tang Department of Mechanical Engineering University of Western Macedonia GR-50100 Kozani Greece Division of Materials sciences & Engineering Ames Lab of DOE Iowa State University Ames IA 450011 USA

We investigated the structural and magnetic properties of sm（Co0.7Fe0.1Ni0.12Zr0.04B0.04）7.5 melt spun ribbons. samples were arc melted then melt spun at 37 m/s up to 55 m/s to obtain ribbon for powdering. Annealing was performed in argon atmosphere for 30- 75 min at 600-870 oC. In as-spun ribbons the hexagonal smCo7 （TbCu7-type of structure） of crystal structure was determined from x-ray diffraction patterns, while fcc-Co has been identified as a secondary phase. After annealing, the 1：7 phase of the as-spun ribbons transformed into 2：17 and 1：5 phases. X-ray patterns for as-milled powders exhibited very broad peaks making it difficult to identify a precise structure but repre-sented the 1：7 structure after annealing at low temperature （650 oC）. TEM analysis showed a homogeneous nanocrystalline microstructure with average grain size of 30-80 nm. Coercivity values of 15-27 kOe were obtained from hysteresis loops traced up to a field of 5 T. The co-ercivity decreased as temperature increases, but it maintained values higher than 5 kOe at 380 oC. The maximum energy product at room temperature increased, as high as 7.2 MGOe, for melt-spun isotropic ribbons produced at higher wheel speeds. Anisotropic ribbons had a maximum energy product close to 12 MGOe.

关键词： melt-spinning microstructure rare-earth permanent magnet coercivity

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Parrondo's paradox for chaos control and anticontrol of fractional-order systems

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Chinese Physics B 2016年第1期25卷 507-513页

作者： Marius-F Danca Wallace K s tang Department of Mathematics and Computer science Avram Iancu University Romanian Institute for science and Technology Department of Electronic Engineering City University of Hong Kong

We present the generalized forms of Parrondo＇s paradox existing in fractional-order nonlinear systems. The gener- alization is implemented by applying a parameter switching （Ps） algorithm to the corresponding initial value problems associated with the fractional-order nonlinear systems. The Ps algorithm switches a system parameter within a specific set of N 〉 2 values when solving the system with some numerical integration method. It is proven that any attractor of the concerned system can be approximated numerically. By replacing the words ＂winning＂ and ＂loosing＂ in the classical Parrondo＇s paradox with ＂order＂ and ＂chaos＂, respectively, the Ps algorithm leads to the generalized Parrondo＇s paradox： chaos1 ＋ chaos2 ＋..- ＋ chaosN = order and order1 ＋ order2 ＋.-. ＋ orderN = chaos. Finally, the concept is well demon- strated with the results based on the fractional-order Chen system.

关键词： Parrondo's paradox chaos control parameter switching algorithm fractional-order Chen system

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Acute liver failure due to natural killer-like T-cell leukemia/ lymphoma: A case report and review of the Literature

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World Journal of Gastroenterology 2006年第25期12卷 4089-4092页

作者： Evan s Dellon shannon R Morris Wozhan tang Cherie h Dunphy Mark W Russo Department of Medicine University of North Carolina school of Medicine Chapel HillNCUnited States Department of Pathology University of North Carolina school of Medicine Chapel HillNCUnited States

Acute liver failure （ALF） is a medical emergency requiring immediate evaluation for liver transplantation. We describe an unusual case of a patient who presented with ascites, jaundice, and encephalopathy and was found to have ALF due to natural killer （NK）-Iike T cell leukemia/lymphoma. The key immunophenotype was CD2＋, CD3＋, CD7＋, CD56＋. This diagnosis, which was based on findings in the peripheral blood and ascitic fluid, was confirmed with liver biopsy, and was a contraindication to liver transplantation. A review of the literature shows that hematologic malignancies are an uncommon cause of fulminant hepatic failure, and that NK-like T-cell leukemia/lymphoma is a relatively recently recognized entity which is characteristically CD3＋ and CD56＋. This case demonstrates that liver biopsy is essential in diagnosing unusual causes of acute liver failure, and that infiltration of the liver with NK-like T-cell lymphoma/leukemia can cause acute liver failure.

关键词： Liver failure Liver transplant Nutaral killer cell

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Estimating and Mapping Extreme Ice Accretion hazard and Load Due to Freezing Rain at Canadian sites

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International Journal of Disaster Risk science 2023年第1期14卷 127-142页

作者： Chao sheng Qian tang h.P.hong Department of Civil and Environmental Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

The ice accretion load in Canadian structural design codes is developed based on an operational ice accretion prediction *** the present study,three models are employed to predict the ice accretion amount on a flat surface and horizontal wire at Canadian *** results confirm that the model used by Canadian practice for predicting ice accretion leads to a conservative estimate as compared to the remaining two *** results also indicate that the use of the Gumbel distribution for the annual maximum ice accretion is adequate for regions prone to ice accretion and that the lognormal distribution may be considered for regions with a moderate or negligible amount of ice *** of the ice accretion hazard at five selected Canadian sites are *** analysis of an equivalent wind speed that is concurrent with the iced wire is carried out,showing that the concurrent wind speed for the 50-year return period value of the annual maximum ice accretion amount is smaller than the 50-year return period value of the annual maximum wind *** is shown that the statistical characteristics of the annual maximum concurrent wind speed on iced wire differ from that of the annual maximum wind speed.

关键词： Canada Concurrent wind speed hazard mapping Ice accretion Probabilistic analysis

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ThERMAL sTABILITY OF NON-EQUILIBRIUs MICROsTRUCTURE IN MICROALLOYED sTEEL DURING REhEATING

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Acta Metallurgica sinica(English Letters) 2007年第5期20卷 313-326页

作者： h.B. Wu h.T. Jiang s.W. Yang D. tang X.L. he National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China Dept. of Materials Physics University of Science and Technology Beijing Beijing 100083 China

Cooled in water after isothermal relaxation of deformed austenite for different times, an Nb-bearing microalloyed steel always exhibits synthetic microstructures, in which bainitic ferrite ,dominates. Dislocation configurations and distributions of strain induced precipitates inside bainitic ferrite of samples relaxed for different times were distinct. When compared with the austenite model steel, which maintained fcc structure even at room temperature, the strain induced precipitates were not found in the sample without relaxation whereas these were distributed outside dislocations in sample relaxed for 1000s. Most of the strain induced precipitates distribute along dislocations and pin dislocations in sample relaxed for appropriate time. After bainitic transformation, the dislocations formed in deformed austenite remain to be pinned by the precipitates. When these samples were reheated to and held at 650 or 700℃, the non-equilibrloas microstructures tended to evolve into equilibrioas ones. The sample relaxed for 60s displayed the highest thermo-stability, whereas microstructure evolution was the quickest in the sample relaxed for 1000s even though it was the softest prior to reheating. Dislocations inside laths got rid of pinning of precipitates, and their polygonization became the precursor to the evolution of microstructures during reheated and held, followed by gradual disappearance of lath boundaries caused by dislocation climbing. Finally, recrystallization occurred and polygonal ferrite appeared. By hardness measurement, it was found that softening is not a single process occurring during reheated, in which hardness fluctuates with time. There were two peaks in the hardness-time curve of each sample having undergone relaxation, while single peak occured in the curve of the sample not being relaxed. These results indicated that the thermo-stability of microstructures was determined by their history of formation to a considerable degree.

关键词： bainite reheating strain induced precipitate pinning microstructures evolution

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