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Congenital heart“Challenges”in Down syndrome

第九届全国结构抗振控制与健康监测学术会议

作者：贾新宇 costas papadimitriou 颜王吉阮家荣

有限元方法是当前工程技术领域对于结构设计、分析及数字孪生模型构建的最佳数值计算工具之一。由于结构的复杂性、材料的离散性,以及制造、安装和测量误差等原因,有限元建模过程中不可避免地存在不确定性因素,多个不确定性因素的耦合... 详细信息

有限元方法是当前工程技术领域对于结构设计、分析及数字孪生模型构建的最佳数值计算工具之一。由于结构的复杂性、材料的离散性,以及制造、安装和测量误差等原因,有限元建模过程中不可避免地存在不确定性因素,多个不确定性因素的耦合作用将可能导致有限元结构或其性能的很大波动甚至失效。近年来,有限元模型修正作为减少有限元模型与实际结构响应误差的有效手段在结构动力学领域受到了广泛关注。过去数十年,经典的贝叶斯系统识别方法因其理论严谨性在有限元模型修正上得到了广泛的应用。然而,需要指出,经典的贝叶斯系统识别框架在合理量化环境因素和模型误差等因素造成的不确定性方面具有明显的局限性,导致其不确定性量化结果偏小,近年来受到了更多的关注。为此,本文提出了一种基于分层贝叶斯学习的统计框架,可有效度量由环境因素或建模误差造成的不确定性,为有限元模型修正提供了一种系统性的概率方法和计算工具。该框架通过对系统参数引入多层超参数概率模型,以更新超参数的方式,有效地度量和识别模型参数的不确定性,并为系统响应的不确定性传播与预测提供了可靠依据。本文基于对单自由度、多自由度线性系统及非线性动力系统研究,通过与传统贝叶斯模型修正框架所得结果进行对比,验证了提出框架在不确定性量化方面的有效性。修正后的有限元模型可进一步应用于结构损伤识别及动力安全评估。

关键词：结构动力学有限元模型修正不确定性分析分层贝叶斯超参数识别

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World Journal of Cardiology 2024年第5期16卷 217-220页

作者： Maria Drakopoulou Panayotis K Vlachakis costas Tsioufis Dimitris Tousoulis Department of First Cardiology Hippokration General HospitalAthens Medical SchoolNational and Kapodistrian University of AthensAthens 11527Greece

In this editorial,we comment on the article by Kong et al published in the recent issue of the World Journal of *** this interesting case,the authors present the challenges faced in managing a 13-year-old patient with Down syndrome(DS)and congenital heart disease(CHD)associated with pulmonary arterial *** this distinct population,the Authors underscore the need for early diagnosis and management as well as the need of a multidisciplinary approach for decision *** seems that the occurrence of CHD in patients with DS adds layers of complexity to their clinical *** editorial aims to provide a comprehensive overview of the intricate interplay between DS and congenital heart disorders,offering insights into the nuanced diagnostic and therapeutic considerations for physicians.

关键词： Down syndrome Congenital heart disease Atrioventricular septal defect Pulmonary hypertension Right heart catheterization

Grafts in Peyronie’s surgery without the use of prostheses:a systematic review and meta-analysis

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Asian Journal of Andrology 2024年第3期26卷 250-259页

作者： Anastasios Natsos Vasileios Tatanis Stavros Kontogiannis Sharon Waisbrod Kristiana Gkeka Mohamed Obaidad Angelis Peteinaris Konstantinos Pagonis costas Papadopoulos Panagiotis Kallidonis Evangelos Liatsikos Petros Drettas Department of Urology University of PatrasPatras 26500Greece Uroclinic Pfaeffikon 8808Switzerland Department of Medical Physics University of PatrasPatras26500Greece Department of Urology Medical University of ViennaVienna 1090Austria

Peyronie’s disease(PD)is characterized by abnormal penile curvature,and various surgical methods have been developed usingdifferent graft ***,there is currently no universal agreement on which type of graft is the *** objective of thisreview was to evaluate the available literature and identify the most effective graft material for penile curvature correction in PD.A literature search was conducted using electronic databases,including PubMed,Scopus,and the Cochrane *** patients,intervention,comparison,and outcome(PICO)approach was used to define the eligibility of *** authors independentlyselected studies,evaluated them,and extracted ***-effect models using the DerSimonian–Laird method were *** were single-arm studies and had a high risk of *** mucosa grafts(BMG)were found to result in the highest penilestraightening rates and were associated with the least de novo erectile *** grafts demonstrated a high successrate in straightening despite a higher mean preoperative curvature,while Tutoplast grafts had a higher incidence of postoperativeerectile *** had the highest percentage of postoperative penile ***,the TachoSil graft showed thebest performance when preoperative curvature is taken into *** on the available literature,BMG appear to be the mosteffective for penile curvature correction in PD,but this is offset by the requirement for low preoperative *** TachoSilgraft shows the best overall performance when preoperative curvature is *** randomized clinical trials arestill needed to determine graft superiority.

关键词： erectile function penile curvature penile grafts Peyronie’s disease

Delayed gastric emptying is associated with pylorus-preserving but not classical Whipple pancreaticoduodenectomy:A review of the literature and critical reappraisal of the implicated pathomechanism

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World Journal of Gastroenterology 2006年第37期12卷 5951-5958页

作者： Kosmas I Paraskevas costas Avgerinos costas Manes Dimitris Lytras Christos Dervenis 2~(nd) Departments of Surgery Agia Olga General Hospital Athens Greece 1~(st) Departments of Surgery Agia Olga General Hospital Athens Greece

Pylorus-preserving pancreaticoduodenectomy （PPPD） is nowadays considered the treatment of choice for periampullary tumors, namely carcinoma of the head, neck, or uncinate process of the pancreas, the ampulla of Vater, distal common bile duct or carcinoma of the peri-Vaterian duodenum. Delayed gastric emptying （DGE） comprises one of the most troublesome complications of this procedure. A search of the literature using Pubmed/IVledline was performed to identify clinical trials examining the incidence rate of DGE following standard Whipple pancreaticoduodenectomy （PD） vs PPPD. Additionally we performed a thorough in-depth analysis of the implicated pathomechanism underlying the occurrence of DGE after PPPD. In contrast to early studies, the majority of recently performed clinical trials demonstrated no significant association between the occurrence of DGE with either PD or PPPD. PD and PPPD procedures are equally effective operations regarding the postoperative occurrence of DGE. Further randomized trials are required to investigate the efficacy of a recently reported （but not yet tested in largescale studies） modification, that is, PPPD with antecolic duodenojejunostomy.

关键词： Pylorus-preserving pancreaticoduodenectomy Whipple pancreaticoduodenectomy Delayed gastric emptying Pancreatic surgery

UAV navigation system using line-based sensor pose estimation

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Geo-Spatial Information Science 2018年第1期21卷 2-11页

作者： Julien Li-Chee-Ming costas Armenakis Department of Earth and Space Science and Engineering Geomatics EngineeringLassonde School of EngineeringYork UniversityTorontoCanada

This work presents a mapping and tracking system based on images to enable a small Unmanned Aerial Vehicle(UAV)to accurately navigate in indoor and GPS-denied outdoor environments.A method is proposed to estimate the UAV’s pose(i.e.,the 3D position and orientation of the camera sensor)in real-time using only the on-board RGB camera as the UAV travels through a known 3D environment(i.e.,a 3D CAD model).Linear features are extracted and automatically matched between images collected by the UAV’s onboard RGB camera and the 3D object *** matched lines from the 3D model serve as ground control to estimate the camera pose in real-time via line-based space *** results demonstrate that the proposed modelbased pose estimation algorithm provides sub-meter positioning accuracies in both indoor and outdoor *** is also that shown the proposed method can provide sparse updates to correct the drift from complementary simultaneous localization and mapping(SLAM)-derived pose estimates.

关键词： Pose estimation modelbased tracking navigation GPS-denied environment

CONTROLLING INFECTIOUS DISEASE OUTBREAKS： A DETERMINISTIC ALLOCATION-SCHEDULING MODEL WITH MULTIPLE DISCRETE RESOURCES

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Journal of Systems Science and Systems Engineering 2017年第2期26卷 219-239页

作者： Nikolaos Rachaniotis Thomas K. Dasaklis costas Pappis Department of Economics Democritus University of Thrace Komotini Greece Department of Industrial Management and Technology University of Piraeus Piraeus Greece

Infectious disease outbreaks occurred many times in the past and are more likely to happen in the future. In this paper the problem of allocating and scheduling limited multiple, identical or non-identical, resources employed in parallel, when there are several infected areas, is considered. A heuristic algorithm, based on Shih＇s （1974） and Pappis and Rachaniotis＇（2010） algorithms, is proposed as the solution methodology. A numerical example implementing the proposed methodology in the context of a specific disease outbreak, namely influenza, is presented. The proposed methodology could be of significant value to those drafting contingency plans and healthcare policy agendas.

关键词： Resource allocation healthcare management epidemics heuristics

Overview of the Association Between Non-Alcoholic Fatty Liver Disease and Hypertension

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Cardiology Discovery 2024年第1期4卷 30-37页

作者： Niki S.Kakouril costas G.Thomopoulos Eirini P.Siafi Angeliki E.Valatsoul Kyriakos S.Dimitriadis Iliana P.Mani Sotirios P.Patsilinakos Dimitrios M.Tousoulis Konstantinos P.Tsioufis First Department of Cardiology Medical SchoolNational and Kapodistrian University of AthensHippokration HospitalAthens 11527Greece Department of Cardiology Elena Venizelou HospitalAthens 11521Greece Department of Cardiology General Hospital Agia OlgaAthens 14233Greece

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and its prevalence is rising. NAFLD is closely associated with metabolic syndrome, with both conditions sharing common clinical characteristics such as obesity, insulin resistance, type 2 diabetes mellitus, hypertension, and hypertriglyceridemia. Several observational studies have evaluated the relationship between NAFLD and hypertension, with the overall evidence suggesting a bidirectional relationship. It is hypothesized that activation of the sympathetic nervous and renin-angiotensin systems, observed in NAFLD with or without insulin resistance promotes the development of hypertension. In patients with hypertension, activation of these systems can lead to hepatic fibrosis and progressive inflammation through increased oxidative stress and activation of hepatic stellate cells and Kupffer cells. The present review examines the pathophysiologic and clinical evidence supporting the bidirectional association between NAFLD and hypertension.

关键词： Hypertension Non-alcoholic fatty liver disease Insulin resistance Sympathetic nervous system Metabolic syndrome

STRUCTURAL HEALTH MONITORING IN COMPOSITE MATERIALS USING EMBEDDED SHAPE MEMORY ALLOY(SMA) WIRE SENSORS

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Chinese Journal of Mechanical Engineering 2006年第3期19卷 446-450页

作者： QIU Zixue YAO Xingtian costas Soutis School of Mechanical Engineering Nantong University Nantong 226007 China Department of Mechanical Engineering The University of Sheffield Sheffield S1 3JD UK

Shape memory alloy （SMA） materials possess completely superelasticity or pseudoelasticity above the austenite finish temperature and many unique mechanical, thermal, thermal-mechanical and electrical properties compared with other conventional materials. Many studies have reported that the superelastic and hysteresis properties of the SMA materials can absorb energies coming from external excitations or sudden impacts. In addition, due to the special electrical properties of NiTi superelastic wires, they can also be used as strain-sensing element to monitor structural health conditions. Composite laminated specimens embedded with SMA wire sensors are fabricated and detailed testing system is designed such as multi-parameters measuring for impact and weak signal processing for SMA sensor. Low velocity impact test shows that SMA wire sensors embedded in fiber-reinforced plastic （FRP） laminate can be well used to monitor impact responses, such as the location of impact damage, impact degree, and strain distribution. Experimental results and theoretical predictions reveal almost the same. Comparing with other method, a simple, economic and reliable technique method monitoring important engineering structures on line is provided.

关键词： Shape memory alloy(SMA) Structural health monitoring Sensor

Are pregnancy-associated hypertensive disorders so sweet?

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World Journal of Clinical Cases 2022年第28期10卷 10384-10386页

作者： costas Thomopoulos Ioannis Ilias Department of Cardiology Elena Venizelou General and Maternity HospitalAthens GR-11521Greece Department of Endocrinology Elena Venizelou General and Maternity HospitalAthens GR-11521Greece

Worldwide,one in seven pregnancies is complicated by some form of diabetes,with a rising ***,hypertension is one of the main causes of morbidity and mortality for both the pregnant woman and the fetus and also contributes to premature *** a cohort study of pregnant women with diabetes,which was recently published in this journal,at least 84.5% of the subjects had *** rate of hypertension might be among the highest reported thus *** the medical literature,approximately 20% of women with diabetes during pregnancy have various pregnancy-associated hypertensive ***/ethnic differences,apparently,were not implicated in this elevated rate of hypertension:Although black and Hispanic women have a twofold higher rate of hypertension in pregnancy compared to white women,75% of the subjects in the study in question were ***,the impressive finding delivered by this large study,merits additional clarifications.

关键词： Pregnancy Hypertension Pre-eclampsia Diabetes Gestational diabetes Human