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Cardiology Discovery 2023年第1期3卷 54-59页

作者： Xiaofeng He Lei Zhang Xuanze Liu Xiaozeng Wang The Department of Cardiology General Hospital of Northern Theater CommandShenyangLiaoning 110016China

A 43-year-old male was admitted to General Hospital of Northern Theater Command with exacerbation of chest pain for 10 d.Computed tomographic angiography(CTA)showed an irregular aortic arch aneurysm involving the left subclavian artery(LSA),with penetrating aortic ulcer and intramural hematoma.A modified fenestrated thoracic endovascular aortic repair(TEVAR)technique was performed successfully.Follow-up CTA showed that stent grafts were well-apposed,without endoleaks,migration,or branch artery occlusion,and the hematoma was almost completely absorbed.In this case,precise fenestrations were created by measurements based on three-dimensional CT reconstruction and angiography.Furthermore,the physician chose an LSA approach to catch the guide wire and deployed branched stent grafts,considering the oblique direction of this branch and the small size of the fenestration.This case shows that pre-fenestrated and inner bare stent enhancing TEVAR is a safe and feasible technique for repair of complicated aortic arch aneurysm.

关键词： Aortic aneurysm Aortic arch Thoracic endovascular aortic repair Pre-fenestrated stent graft Branched stent graft Case report

PDGF signaling from pharyngeal pouches promotes arch artery morphogenesis

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Journal of Genetics and Genomics 2019年第12期46卷 551-559页

作者： Aihua Mao Mingming Zhang Jie Liu Yu Cao Qiang Wang State Key Laboratory of Membrane Biology Institute of ZoologyUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing100101China

The great vessels of the heart originate from the pharyngeal arch arteries(PAAs).Anomalies of the PAAs often occur together with pharyngeal pouch malfo rmations,but the reasons for this phenomenon are not fully understood.In the current study,we show that platelet-derived growth factor(PDGF)signaling derived from the pharyngeal pouches plays an important function in PAA vasculogenesis,During PAA development in zebrafish embryos,pdgfaa and pdgfab are expressed in the developing pharyngeal pouches.Results from loss-of-function experiments revealed a critical role of these genes in PAA formation.We found that nitroreductase(NTR)-mediated pouch ablation distinctly decreased PDGF receptor tyrosine phosphorylation,yielding a severe loss of PAAs.Importantly,pouch-specific overexpression of pdgfaa in pdgfaa-/-;pdgfab-/-mutants significantly relieved the PAA defects,which indicated a primary role of pharyngeal pouch-expressed PDGF ligands in signal activation and PAA morphogenesis.Our findings further showed that PDGF signaling was indispensable for the proliferation of PAA angioblasts.Together,these results established a role for PDGFaa-and PDGFab-mediated tissuetissue interaction during PAA development.

关键词： PDGFαa PDGFαb Pharyngeal pouch Pharyngeal arch artery Tissue-tissue interaction Zebrafish

Effects of rotational components of earthquake on seismic response of arch concrete dams

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 349-362页

作者： Amir Javad Moradloo Abbas Naiji Department of Civil Engineering School of EngineeringUniversity of ZanjanZanjan 38791-45371Iran

The present study deals with dynamic analysis of arch concrete dams,taking rotational components of earthquakes into account.A modified methodology was used to evaluate the rotational components of the earthquake.The translational components of the earthquake have been used in to obtain the rotational components of the earthquake,based on the intersecting isotropic elastic wave propagation.Two rotational components of Taft,Tabas and San-Fernando earthquakes are evaluated based on the translational components of the earthquakes and considering frequency dependencies of incident angle and wave velocity.Finally,dynamic analyses of Morrow Point Dam are presented to evaluate the effects of combined translational and rotational components on the seismic response of the dam.Various conditions of reservoirs,including full and empty state,are considered in the analyses.Fluid–structure interaction was completely taken into account.It was realized that incorporating rotational components increased the maximum compressive and tensile stresses in both empty and full reservoir analyses.Distribution of maximum tensile stresses is very sensitive to the rotational components of the earthquake.Also,it can be concluded that the segregated effect of the rocking component on the response of concrete dams is more effective than the sole effect of the torsional component.

关键词： rotational components earthquake arch concrete dam seismic analysis fluid-structure interaction

Association between cardiopulmonary bypass time and 90-day postoperative mortality in patients undergoing arch replacement with the frozen elephant trunk: a retrospective cohort study

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Chinese Medical Journal 2019年第19期132卷 2325-2332页

作者： Jun Zheng Shang-Dong Xu You-Cong Zhang Kai Zhu Hui-Qiang Gao Kai Zhang Xiu-Feng Jin Tong Liu Center of Cardiac Surgery Beijing Aortic Disease CenterBeijing Institute of HeartLung and Blood Vessel DiseaseBeijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Center of Cardiology Beijing Institute of HeartLung and Blood Vessel DiseaseBeijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

Background:The aortic arch replacement and cardiopulmonary bypass(CPB)are both associated with the early mortality after cardiothoracic surgery.This study aimed to investigate the relationship between CPB time and 90-day post-operative mortality in patients undergoing aortic arch surgery using the frozen elephant trunk(FET)technique with selective ante-grade cerebral perfusion(SACP).Methods:We retrospectively reviewed data of 377 adult patients undergoing aortic arch surgery via FET with SACP from July 1,2017 to December 31,2018 at Beijing Anzhen Hospital.The baseline characteristics,intra-operative data,and post-operative data were collected.Univariate and multivariate Cox regression analyses were used to determine independent predictors of 90-day postoperative mortality.Results:The 90-day post-operative mortality was 13.53%.The 78.51%of patients were men.There were 318(84.35%)type A aortic dissections and 28(7.43%)aortic aneurysms.Among those,264(70.03%)were emergency operations.Median CPB time was 202.0(176.0,227.0)min.Multivariate Cox regression analysis revealed that CPB time was independently associated with 90-day post-operative mortality after adjusting confounding factors(hazard ratio:1.21/10 min increase in CPB time,95%confidence interval:1.15–1.27,Parch surgery using FET with SACP.Surgeons should be aware of the relationship between CPB time and 90-day post-operative mortality during operative procedures and avoid extended CPB time as far as possible.

关键词： Aortic arch replacement Moderate hypothermia circulatory arrest Selective ante-grade cerebral perfusion Frozen elephant trunk Cardiopulmonary bypass time Mortality

Predicting asymptomatic coronary artery stenosis by aortic arch plaque in acute ischemic cerebrovascular disease:beyond the cervicocephalic atherosclerosis?

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Chinese Medical Journal 2019年第8期132卷 905-913页

作者： Xin Ma Qi Kong Chen Wang Gary Rajah Yu-Chuan Ding Yu-Ren Zhang Xiang-Ying Du Department of Neurology. Xuanwu Hospital Capital Medical University Beijing 100053 China Department of Radiology Xuanwu Hospital Capital Medical University Beijing 100053 China Department of Neurosurgery Wayne State University School of Medicine Detroit 48201 USA Department of Biostatistics Yale University School of Public Health New Haven 06520 USA

Background:Asymptomatic coronary artery stenosis(ACAS)≥50%is common in patients with acute ischemic cerebrovascular disease(AICVD),which portends a poor cardiovascular and cerebrovascular prognosis.Identifying ACAS>50%early may optimize the clinical management and improve the outcomes of these high-risk AICVD patients.This study aimed to investigate whether aortic arch plaque(AAP),an early atherosclerotic manifestation of brain blood-supplying arteries,could be a predictor for ACAS>50%in AICVD.Methods:In this cross-sectional study,atherosclerosis of the coronary and brain blood-supplying arteries was simultaneously evaluated using one-step computed tomography angiography(CTA)in AICVD patients without coronary artery disease history.The patients were divided into ACAS≥50%and non-ACAS≥50%groups according to whether CTA showed stenosis≥50%in at least one coronary arterial segment.The AAP characteristics of CTA were depicted from aspects of thickness,extent,and complexity.Results:Among 118 analyzed patients with AICVD,29/118(24.6%)patients had ACAS≥50%,while AAPs were observed in 86/118(72.9%)patients.Increased AAP thickness per millimeter(adjusted odds ratio[OR]:1.56,95%confidence interval[CI]:1.18-2.05),severe-extent AAP(adjusted OR:13.66,95%CI:2.33-80.15),and presence of complex AAP(adjusted OR:7.27,95%CI:2.30-23.03)were associated with ACAS≥50%among patients with AICVD,independently of clinical demographics and cervicocephalic atherosclerotic stenosis.The combination of AAP thickness,extent,and complexity predicted ACAS≥50%with an area under the receiver-operating characteristic curve of 0.78(95%CI:0.70-0.85,P<0.001).All three AAP characteristics provided additional predictive power beyond cervical and intracranial atherosclerotic stenosis for ACAS≥50%in AICVD(all P<0.05).Conclusions:Thicker,severe-extent,and complex AAP were significant markers of the concomitant ACAS≥50%in AICVD,possibly superior to the indicative value of cervical and intracranial atherosclerotic stenosis.As an integral part of atherosclerosis

关键词： Asymptomatic coronary artery stenosis Aortic arch plaque Acute ischemic cerebrovascular disease Atherosclerosis Prediction

The best option for complicated type B dissection with arch involved

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Chinese Medical Journal 2021年第8期134卷 883-885页

作者： Chang Shu Tun Wang Ming-Yao Luo Kun Fang Quan-Ming Li Ming Li Xin Li Hao He Departm ent of Vascular Surgery The 2nd Xiang-ya HospitalCentral South UniversityChangshaHunan 410011China Angiopathy Institute Central South UniversityChangshaHunan 410011China Department of Cardiovascular Surgery Chinese Academy of Medical Sciences and Peking Union Medical College Fuwai HospitalBeijing 100013China.

Thoracic endovascular aortic repair(TEVAR)is the first choice of type B aortic dissection(T B A D).U However,when the dissection involves an aortic arch with close proximity to the supra-aortic branches,the situation becomes complicated and challenging for classical TEVAR.In recent years,the Hybrid-ENDO vascular-Open arch repair(HENDO)theory that consists of some treatment strategies specifically for aortic arch lesions,becomes popular.Based on the HENDO theory,the modified endovascular technique,simultaneously aiming at the reconstruction of the involved supra-aortic branches and coverage of TBAD,is the first choice with promising future development.According to the specific anatomic situation and the pathology of the disease,hybrid or open surgery can be performed selectively.

关键词： dissection arch complicated

Seismic design of Xiluodu ultra-high arch dam

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Water Science and Engineering 2018年第4期11卷 288-301页

作者： Ren-kun Wang Lin Chen Chong Zhang PowerChina Chengdu Engineering Corporation Limited Chengdu 610072 China

The 285.5 m-high Xiluodu arch Dam is located in a seismic region along the Jinsha River in China, where the horizontal components of peak ground accelerations for design and checking earthquakes have been estimated to be 0.355 g and 0.423 g, respectively( g is the gravitational acceleration). The ground motion parameters of design and checking earthquakes are defined by exceedance probabilities of 2% over 100 years and 1% over 100 years, respectively. The dam shape was first selected and optimized through static analysis of the basic load combinations, and then adjusted after taking into account the seismic loads. The dam should be operational during and after the design earthquake with or without minor repairs, and maintain local and global stabilities during an extreme earthquake. Both linear elastic dynamic analysis and nonlinear dynamic analysis considering radiation damping, contraction joints, and material nonlinearity were conducted to assess the stress in the arch dam.The dynamic analysis shows that the maximum dynamic compressive stresses are less than the allowable levels, while the area with tensile stress over the limit is less than 15% of the dam surface and the maximum contraction openings range from 10 mm to 25 mm. The arch dam has sufficient earthquake-resistance capacity and meets the safety requirements. Nevertheless, steel reinforcement has been provided at the dam toe and in the zones of high tensile stress on the dam surface out of extra precaution.

关键词： Seismic design Nonlinear dynamic analysis Dam shape optimization Seismic strengthening Xiluodu arch dam

Reliability and variance-based sensitivity analysis of arch dams during construction and reservoir impoundment

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 526-541页

作者： M.Houshmand KHANEGHAHI M.ALEMBAGHERI N.SOLTANI Department of Civil Engineering Shahid Beheshti UniversityTehranIran Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The static performance of arch dams during construction and reservoir impoundment is assessed taking into account the effects of uncertainties presented in the model properties as well as the loading conditions.Dez arch dam is chosen as the case study;it is modeled along with its rock foundation using the finite element method considering the stage construction.Since previous studies concentrated on simplified models and approaches,comprehensive study of the arch dam model along with efficient and state-of-the-art uncertainty methods are incorporated in this investigation.The reliability method is performed to assess the safety level and the sensitivity analyses for identifying critical input factors and their interaction effects on the response of the dam.Global sensitivity analysis based on improved Latin hypercube sampling is employed in this study to indicate the influence of each random variable and their interaction on variance of the responses.Four levels of model advancement are considered for the dam foundation system:1)Monolithic dam without any joint founded on the homogeneous rock foundation,2)monolithic dam founded on the inhomogeneous foundation including soft rock layers,3)jointed dam including the peripheral and contraction joints founded on the homogeneous foundation,and 4)jointed dam founded on the inhomogeneous foundation.For each model,proper performance indices are defined through limit-state functions.In this manner,the effects of input parameters in each performance level of the dam are investigated.The outcome of this study is defining the importance of input factors in each stage and model based on the variance of the dam response.Moreover,the results of sampling are computed in order to assess the safety level of the dam in miscellaneous loading and modeling conditions.

关键词： concrete arch dams reliability randomness improved Latin hypercube sampling variance-based sensitivity analysis exceedance probability Sobol index

Persistent fifth aortic arch stenosis associated with type A interruption of the aortic arch: a report of six cases

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Chinese Medical Journal 2019年第12期132卷 1482-1484页

作者： Lin Zheng Yong-Li Cao Rong-Chang Wu Jian Guo Ning Ma Fang-Yun Wang Xin Zhang Yun Peng Department of Echocardiography Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Radiology Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Cardiac Surgery Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China

Persistent fifth aortic arch (PFAA) is a rare congenital cardiovascular malformation that occurs when the pharyngeal fifth aortic arch does not degenerate during the embryonic period. The first case of PFAA was described in an autopsy specimen in 1969.[1] In 1973, the persistence of a left fifth aortic arch was first reported.[2] Since then, several case reports have described PFAA in different forms. PFAA stenosis associated with type A interruption of the aortic arch (type-A IAA) is most common in clinical practice and requires surgical intervention. From 2013 to 2018, six cases [Table 1 and Table 2] were diagnosed using echocardiography and computed tomography angiography (CTA). Five cases were successfully treated with surgery and followed-up. The purpose of this study was to summarize the clinical characteristics and diagnostic features of PFAA stenosis associated with type-A IAA to improve its diagnostic accuracy and allow for complete pre-operative preparation and proper treatment.

关键词： Persistent fifth aortic arch stenosis type A interruption six cases

Chaos and Nonlinear Feedback Control of the arch Micro-Electro-Mechanical System

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Journal of Systems Science & Complexity 2018年第6期31卷 1510-1524页

作者： LUO Shaohua LI Shaobo TAJADDODIANFAR Farid Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang 550025China Schbol of Mechanical Engineering Guizhou UniversityGuiyang 550025China. Department of Mechanical Engineering Erik Jonsson School of Engineering and Computer ScienceThe Uni-versity of Texas at DallasRichardson TX 75080USA.

This paper addresses a nonlinear feedback control problem for the chaotic arch micro- electro-mechanical system with unknown parameters,immeasurable states and partial state-constraint subjected to the distributed electrostatic actuation.To reflect inherent properties and design controller, the phase diagrams,bifurcation diagram and Poincare section are presented to investigate the nonlinear dynamics.The authors employ a symmetric barrier Lyapunov function to prevent violation of constraint when the arch micro-electro-mechanical system faces some limits.An RBF neural network system integrating with an update law is adopted to estimate unknown function with arbitrarily small error. To eliminate chaotic oscillation,a neuro-adaptive backstepping control scheme fused with an extended state tracking differentiator and an observer is constructed to lower requirements on measured states and precise system model.Besides,introducing an extended state tracking differentiator avoids repeated derivative for the virtual control signal associated with conventional backstepping.Finally,simulation results are presented to illustrate feasibility of the proposed scheme.

关键词： arch micro-electro-mechanical system chaos suppression Neuro-adaptive backstepping nonlinear feedback control uncertainty.