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Stochastic seismic slope stability assessment using polynomial chaos expansions combined with relevance vector machine

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Geoscience Frontiers 2021年第1期12卷 405-414页

作者： Qiu-Jing Pan Yat-Fai Leung shu-chien Hsu School of Civil Engineering Central South UniversityNo.22Shaoshan South RoadChangsha410075China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomHong KongChina

This paper presents probabilistic assessment of seismically-induced slope displacements considering uncertainties of seismic ground motions and soil properties.A stochastic ground motion model representing both the temporal and spectral non-stationarity of earthquake shakings and a three-dimensional rotational failure mechanism are integrated to assess Newmark-type slope displacements.A new probabilistic approach that incorporates machine learning in metamodeling technique is proposed,by combining relevance vector machine with polynomial chaos expansions(RVM-PCE).Compared with other PCE methods,the proposed RVM-PCE is shown to be more effective in estimating failure *** sensitivity and relative influence of each random input parameter to the slope displacements are ***,the fragility curves for slope displacements are established for sitespecific soil conditions and earthquake hazard *** results indicate that the slope displacement is more sensitive to the intensities and strong shaking durations of seismic ground motions than the frequency contents,and a critical Arias intensity that leads to the maximum annual failure probabilities can be identified by the proposed approach.

关键词： Earthquake 3D slope stability Failure probability Seismic displacements Seismic hazard analysis

Hepatitis B virus infection and renal transplantation

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World Journal of Gastroenterology 2010年第31期16卷 3878-3887页

作者： Ming-Chao Tsai Yen-Ta Chen Yu-shu chien Tsung-Hui Hu Division of Hepato-Gas-troenterology Department of Internal MedicineChang Gung Memorial HospitalKaohsiung Medical CenterChang Gung University College of Medicine123Ta-Pei RoadNiao-Sung HsiangKaohsiung Hsien 833Taiwan China Department of Urology Chang Gung Memorial HospitalKaohsiung Medical CenterChang Gung University College of Medicine123Ta-Pei RoadNiao-Sung HsiangKaohsiung Hsien 833 TaiwanChina Division of Nephrology De-partment of Internal MedicineChang Gung Memorial HospitalKaohsiung Medical CenterChang Gung University College of Medicine123Ta-Pei RoadNiao-Sung HsiangKaohsiung Hsien 833Taiwan China

Although the prevalence of chronic hepatitis B virus (HBV) infection has declined in renal transplant recipients (RTRs), it remains a relevant clinical problem with high morbidity and mortality in long-term follow up. A thorough evaluation, including liver biopsy as well as assessment of HBV replication in serum (i.e. hepatitis B e antigen and/or HBV DNA) is required before transplantation. Interferon should not be used in this setting because of low efficacy and precipitation on acute allograft rejection. The advent of effective antiviral therapies offers the opportunity to prevent the progression of liver disease after renal transplantation. However, as far as we are aware, no studies have compared prophylactic and preemptive strategies. To date, the majority of RTRs with HBV-related liver disease have had a high virological and biochemical response to lamivudine use. However, lamivudine resistance is frequent with a prolonged course of therapy. Considering long-term treatment, antiviral agents with a high genetic barrier to resistance and lack of nephrotoxicity are suggested. The optimal strategy in RTRs with HBV infection remains to be established in the near future.

关键词： Hepatitis B Renal transplantation Lamivudine resistance

Effect of verapamil on nitric oxide synthase in a portal veinligated rat model: Role of prostaglandin

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World Journal of Gastroenterology 2006年第15期12卷 2351-2356页

作者： Chii-Shyan Lay CMY May Fa-Yauh Lee Yang-Te Tsai Shou-Dong Lee shu chien Shiomoh Sinchon Division of Hepatology and Gastroenterology Department of Internal Medicine China Medical University HospitalTaichungChina Division of Gastroenterology Department of Internal Medicine Veterans General HospitalTaipeiNational Yang-Ming University School of MedicineTaipeiChina Institute of Biomedical Sciences Academia Sinica TaiwanChina Department of Medicine Columbia University New York University Medical CenterNew YorkUSA

AIM： To investigate the effects of verapamil on nitric oxide （NO） synthesis in a portal vein-ligated rat model. METHODS： Systemic and splanchnic hemodynamics were measured by radiolabeled microspheres in portal hypertensive rats after acute administration of verapamil （2 mg/kg） on chronic treatment with N^W-nitro-L-arginine （NNA）（80 mg/kg） and/or indomethacin （2 mg/kg） . RESULTS： Verapamil （2 mg/kg） caused a marked fall in both arterial pressure and cardiac output accompanied by an insignificant change in the portal pressure and no change in portal venous inflow. This result suggested that verapamil did not cause a reduction in portal vascular resistance of portal hypertensive rats, which was similar between N^w- nitro-Loarginine-treated and indomethacin-treated groups. CONCLUSION： In portal hypertensive rats pretreated with NNA and/or indomethacin, acute verapamil administration can not reduce the portal pressure, suggesting that NO and prostaglandin play an important role in the pathogenesis of splanchnic arterial vasodilation in portal hypertension.

关键词： Verapamil Nitric oxide synthase Portal hypertension

Synthesis and characterization of Cu-Pt/MWCNTs for use in electrocatalytic applications

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Particuology 2011年第5期9卷 522-527页

作者： Yuh-Jing Chiou Hang-Jui Hsu Hong-Ming Lin Wei-Jen Liou Huey-Wen Liou She-Huang Wu shu-Hua chien Department of Materials Engineering Tatung University 40 Chungshan N. Rd. 3rd Sec 104 Taipei Taiwan China Institute of Chemistry Academia Sinica 128Academia Road Sec. 2 Nankang 115 Taipei Taiwan China

Improving catalyst performance by studying the preparation parameters, material structures and analysis methods is important work for catalyst researchers. In this study, Cu-Pt nanocomposites with different metal ratios were synthesized on MWCNTs using a polyol method. The structures and morphologies of the nano hybrid catalysts were analyzed by XRD and TEM. The XRD results indicate that Pt and Cu formed a bimetallic solid solution. The average diameters of the Pt and Cu-Pt nanoparticles on MWCNTs were between 3-10 nm and 5-15 nm, respectively. The electrocatalytic behavior of methanol oxidation reactions was investigated by cyclic voltammery （CV）. Cu（20%）/[Pt/MWCNTs（1：4）], which contained an optimal degree of solid solution, enhanced the methanol oxidation to the greatest degree.

关键词： Electrocatalysis Methanol Multi-walled carbon nanotubes NanoparticlesPlatinumCopper

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应力方向对内皮细胞力学传递和功能的影响

北京大学学报（自然科学版） 2007年第4期43卷 435-440页

作者：钱煦美国加州大学圣地亚哥分校生物工程系医学系

剪切力可经由应力感受、信息传递和基因与蛋白质的表达来调控血管内皮细胞的功能。层流剪切力会导致单核细胞趋化蛋白质(MCP-1)及多种增生基因的迅速上调。但有特定方向的持久层流剪切力会使MCP-1及增生基因与蛋白下调,同时并上调抑制... 详细信息

剪切力可经由应力感受、信息传递和基因与蛋白质的表达来调控血管内皮细胞的功能。层流剪切力会导致单核细胞趋化蛋白质(MCP-1)及多种增生基因的迅速上调。但有特定方向的持久层流剪切力会使MCP-1及增生基因与蛋白下调,同时并上调抑制内皮细胞增生的基因与蛋白。复杂的流型没有什么固定的方向,会使MCP-1及增生基因持续上调,因而增加单核细胞的侵入及内皮细胞的分裂及凋亡。在动脉的直管部分,层流剪切力有特定的方向,因此有抗动脉粥样硬化的作用。在动脉分支部位,复杂的流型有促使动脉粥样硬化的作用。所以,应力的方向对内皮细胞在正常及疾病时的功能有重要影响。

关键词：粥样硬化基因表达整合素剪切力信息传递

Mechanotransduction in vascular cells in health and disease

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Mechanotransduction in vascular cells in health and disease

Mechanotransduction and vascular biology

2012国际生理学学术大会

作者： shu chien Departments of Bioengineering and Medicine and Institute of Engineering in Medicine University of California San Diego La JollaCaliforniaUSA

＜正＞Vascular endothelial cells（ECs） play significant roles in regulating circulatory *** stimuli,including the stretch and shear stress resulting from circulatory pressure and flow,modulate EC functions by activating mechano-sensors,signaling pathways,and gene and protein *** forces with a clear direction（e.g.,the pulsatile shear stress and the uniaxial circumferential stretch existing in the straight part of the arterial tree） cause only transient molecular signaling of pro-inflammatory and proliferative pathways, which become down-regulated when such directed mechanical forces are *** contrast,mechanical forces without a definitive direction（e.g.,disturbed flow and relatively undirected stretch seen at branch points and other regions of complex geometry） cause sustained molecular signaling of pro-inflammatory and proliferative pathways. The EC responses to directed mechanical stimuli involve the remodeling of EC structure to minimize alterations in intracellular stress/strain and elicit adaptive changes in EC signaling in the face of sustained stimuli;these cellular events constitute a feedback control mechanism to maintain vascular homeostasis and are *** a feedback mechanism does not operate effectively in regions of complex geometry,where the mechanical stimuli do not have clear directions,thus placing these areas at risk for *** differential modulation of EC functions by various flow patterns involves intricate interplays of signaling pathways and gene *** mechanotransduction-induced EC adaptive processes in the straight part of the aorta provide a mechanical and molecular mechanism for the maintenance of cellular homeostasis in the face of external perturbations.

关键词： vascular endothelial cells mechanotransduction atherogenesi

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Mechanotransduction and vascular biology

Shear stress induces synthetic-to-contractile phenotypic modulation in smooth muscle cells via PPAR-alpha/delta activations by prostacyclin released by sheared endothelial cells

2008北京国际生理科学学术大会

作者： chien shu Departments of Bioengineering and Medicine University of CaliforniaSan Diego La JollaCAUSA

＜正＞Mechanical forces,including the shear stress resulting from blood flow and the circumferential stretch due to transmural pressure,can modulate the functions of endothelial cells（ECs）through mechanotransduction. Laminar or pulsatile shear stress with a significant forward direction causes a transient activation of expression of pro-proliferative and pro-inflammatory genes,e.g.,MCP-1,and followed by their down-regulation;such directional shear flow also causes the activation of growth arrest genes,e.g.,***,flow patterns with a significant forward component are *** contrast,the disturbed flow seen at curved regions and branch points of the arterial tree in vivo or the oscillatory perfusion flow in vitro without a significant net forward direction causes the continued activation of chemoattractants and stimulation of cell *** flow patterns also lead to different responses in cytoskeletal remodeling and intracellular stress *** stresses with a significant net direction cause the alignment of actin stress fibers in the flow direction to minimize the intracellular *** respond differentially to uniaxial and biaxial *** stretch with a clear direction causes a Rho-dependent orientation of actin stress fibers perpendicular to the direction of *** contrast, biaxial stretch without a defined direction does not cause such *** stretch causes transient JNK activation to inhibit EC proliferation and protect ECs against *** contrast,biaxial stretch causes sustained JNK activation that leads to EC *** results indicate that the temporal and spatial variations in shear stress and stretch,especially the presence or absence of directionality,result in differential modulations of signal transduction,gene expression,and protein expressions,as well as EC functions and vascular biology in health and disease.

关键词： meehanotransduction vascular biovgy shear stress signal transduction

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Shear stress induces synthetic-to-contractile phenotypic mod...

Warmest Congratulations to the Journal of Medical Biomechanics on Its 30^(th) Anniversary

第七届海峡两岸心血管科学研讨会

作者： Min-chien Tsai shu chien Jeng-Jiann Chiu Division of Medical Engineering Research National Health Research InstitutesMiaoliTaiwan

Phenotypic modulation of smooth muscle cells(SMCs),which are located in close proximity to endothelial cells(ECs),is critical in regulating vascular *** investigated the role of flow-induced shear stress on ECs in modulating SMC phenotype and its underlying mechanism,using our newly developed EC/SMC co-culture flow system in which ECs and SMCs were separated by a porous *** of shear stress(12 dynes/ cm)to EC/SMC modulated SMC phenotype from synthetic to contractile state,with up-regulation of contractile markers,down-regulation of pro-inflammatory genes,and decreased percentage of cells in the synthetic phase. Treating SMCs with media from sheared ECs induced peroxisome proliferator-activated receptor(PPAR)-α,-δ, and-γligand binding activities;transfecting SMCs with specific small interfering RNAs(siRNAs)of PPAR-αand-δ, but not-γ,inhibited shear-induction of contractile *** exposed to shear stress released prostacyclin (PGI).Transfecting ECs with PGI synthase-specific siRNA inhibited shear-induced activation of PPAR-α/δ,up-regulation of contractile markers,down-regulation of pro-inflammatory genes,and decrease in percentage of SMCs in synthetic *** with PPAR-αdeficiency showed altered SMC phenotype toward a synthetic state,with increased arterial contractility in response to angiotensinⅡ,as compared with control *** results indicate that laminar shear stress induces synthetic-to-contractile phenotypic modulation in SMCs through the activation of PPAR-α/δby the EC-released *** findings provide insights into the mechanisms underlying the interplays of ECs with SMCs and the protective homeostatic function of laminar shear stress in modulating SMC phenotype.

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医用生物力学 2016年第4期31卷 F0002-F0002页

作者： shu chien University Professor of Bioengineering and Medicine and Director Institute of Engineering in Medicine University of California

It is my great pleasure and privilege to write this message of congratulation to commemorate the auspicious occasion of the 30^(th) anniversary of the Journal of Medical Biomechanics(JMB),which was first published in 1986 as the Journal of *** JMB,which is sponsored by Shanghai Jiao Tong University and supervised by the Ministry of Education of People’s Republic of China,has made outstanding accomplishments over the thirty-year period since its *** is

关键词：作者介绍编辑工作主编《医学生物力学》