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A Simple and Efficient Structural Topology Optimization Implementation Using Open-Source Software for All Steps of the Algorithm:Modeling, Sensitivity Analysis and Optimization

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1371-1397页

作者： rafael marin Ferro Renato Pavanello Coordination of Mechanical Engineering Federal Institute of Science and Technology of ES-IFESAracruz-ES29192-733Brazil Department of Computational Mechanics Faculty of Mechanical EngineeringUnicampCampinas-SP13083-860Brazil

This work analyzes the implementation of a continuous method of structural topology optimization(STO)using open-source software for all stages of the topology optimization problem:modeling,sensitivity analysis and optimization.Its implementation involves three main components:numerical analysis using the Finite Element Method(FEM),sensitivity analysis using an Adjoint method and an optimization solver.In order to allow the automated numerical solution of Partial Differential Equations(PDEs)and perform a sensitivity analysis,FEniCS and Dolfin Adjoint software are used as tools,which are open-source code.For the optimization process,Ipopt(Interior Point OPTimizer)is used,which is a software package for nonlinear optimization scale designed to find(local)solutions of mathematical optimization problems.The topological optimization method used is based on the SIMP-Solid IsotropicMaterial with Penalization interpolation.The considered problem is the minimization of compliance/maximization of stiffness,considering the examples of recurrent structures in the literature in 2D and 3D.A density filtering algorithm based on Helmholtz formulation is used.The complete code involves 51 lines of programming and is presented and commented in detail in this article.

关键词： Structural topology optimization finite element method FEniCS Dolfin Adjoint

The “Brain Stress Timing” phenomenon and other misinterpretations of randomized clinical trial on aneurysmal subarachnoid hemorrhage

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Neural Regeneration Research 2019年第8期14卷 1364-1366页

作者： rafael Martinez-perez Natalia Rayo Agustin Montivero Jorge Marcelo Mura Division of Neurosurgery Institute of Clinical Neurosciences Universidad Austral de Chile Valdivia Chile Division of Cerebrovascular and Skull Base Neurosurgery Institute of Neurosurgery Dr Asenjo Santiago Chile Western University London ON Canada

Clipping and coiling are currently the two alternatives in treatment of ruptured cerebral aneurysms. In spite of some meritorious analysis, further discussion is helpful to understand the actual state of art. Retreatment and rebleeding rates clearly favors clipping, although short-term functional outcome seems to be beneficial for clipping, while this different is not such if we perform the comparison at a longer follow up. Longterm follow ups and cost analysis are mandatory to have a clear view of the current picture in treatment of subarachnoid hemorrhage. Treatment strategy should be made by a multi-disciplinary team in accredited centers with proficient experience in both techniques.

关键词： sAH subarachnoid hemorrhage coiling clipping ruptured aneurysm timing intracranial

Role of endoscopic ultrasound in the diagnosis of pancreatic cancer

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World Journal of Gastrointestinal Oncology 2014年第9期6卷 360-368页

作者： Juana Gonzalo-marin Juan Jose Vila Manuel perez-Miranda Unit of Endoscopy Department of GastroenterologyQuirón Hospital Unit of Endoscopy Department of GastroenterologyComplejo Hospitalario de Navarra Department of Gastroenterology Hospital Universitario Rio Hortega

Endoscopic ultrasonography(EUS) with or without fine needle aspiration has become the main technique for evaluating pancreatobiliary disorders and has proved to have a higher diagnostic yield than positron emission tomography,computed tomography(CT) and transabdominal ultrasound for recognising early pancreatic tumors.As a diagnostic modality for pancreatic cancer,EUS has proved rates higher than 90%,especially for lesions less than 2-3 cm in size in which it reaches a sensitivity rate of 99% vs 55% for CT.Besides,EUS has a very high negative predictive value and thus EUS can reliably exclude pancreatic cancer.The complication rate of EUS is as low as 1.1%-3.0%.New technical developments such as elastography and the use of contrast agents have recently been applied to EUS,improving its diagnostic capability.EUS has been found to be superior to the recent multidetector CT for T stagingwith less risk of overstaying in comparison to both CT and magnetic resonance imaging,so that patients are not being ruled out of a potentially beneficial resection.The accuracy for N staging with EUS is 64%-82%.In unresectable cancers,EUS also plays a therapeutic role by means of treating oncological pain through celiac plexus block,biliary drainage in obstructive jaundice in patients where endoscopic retrograde cholangiopancreatography is not affordable and aiding radiotherapy and chemotherapy.

关键词： modality staging potentially diagnostic transabdominal celiac retrograde plexus chemotherapy adenocarcinoma

Role of artificial intelligence in cardiology

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World Journal of Cardiology 2023年第4期15卷 116-118页

作者： rafael Vidal-perez Jose Manuel Vazquez-Rodriguez Servicio de Cardiología Unidad de Imagen y Función CardíacaComplexo Hospitalario Universitario A Coruña Centro de Investigación Biomédica en Red-Instituto de Salud Carlos ⅢA Coruña 15006A CoruñaSpain Servicio de Cardiología Complexo Hospitalario Universitario A CoruñaA Coruña 15006A CoruñaSpain

Artificial intelligence(AI)is the process of having a computational program that can perform tasks of human intelligence by mimicking human thought processes.AI is a rapidly evolving transdisciplinary field which integrates many elements to develop algorithms that aim to simulate human intuition,decision-making,and object recognition.The overarching aims of AI in cardiovascular medicine are threefold:To optimize patient care,improve efficiency,and improve clinical outcomes.In cardiology,there has been a growth in the potential sources of new patient data,as well as advances in investigations and therapies,which position the field well to uniquely benefit from AI.In this editorial,we highlight some of the main research priorities currently and where the next steps are heading us.

关键词： Artificial intelligence Machine learning Deep learning Electrocardiography Cardiac imaging

Ligaments disruption:a new perspective in the prognosis of spinal cord injury

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Neural Regeneration Research 2014年第5期9卷 456-457页

作者： rafael Martinez-perez Luis Jimenez-Roldan Alfonso Lagares Department of Neurosurgery of Hospital 12 de Octubre Universidad Complutense de Madrid Faculty of Medicine

The worldwide prevalence of spinal cord injury （SCI） ranges from 233 to 755 per million inhabitants, whereas the report- ed incidence lies between 10.4 and 83 per million inhabitants annually （Wyndaele and Wyndaele, 2006）. Thus, the socio- economic impact of SCI associated with cervical trauma is high enough that it could become an important concern in the vast majority of developed countries.

关键词： Ligaments disruption SCI

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria rafael perez-Gonzalez Christian Gomez-Solis Luis Armando Diaz-Torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 nm.Microscopy images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential direction.TiWNi NPs presented a mixture of anatase/rutile phases with cubic structure.The performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible light.The results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),respectively.Thus,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF degradation.Raman/absorbance measurements confirmed the presence of such defects.Moreover,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their degradation.The results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

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迷走神经与肺部疾病(英文)

复旦学报（医学版） 2012年第2期39卷 117-122页

作者：宋娜娜刘俊 Bogdan Moldoveanu Juan Guardiola rafael perez 於峻美国肯塔基州路易维尔大学医学系呼吸内科路易维尔40292

迷走神经支配人体的内脏器官,其传出纤维激活后可释放乙酰胆碱调节器官功能,而传入纤维能感知器官中机械和化学信号,并将其传入中枢,这种双向交流使得神经中枢能够反馈性调节器官功能。在呼吸系统中,迷走神经调节气道张力、血流供应、... 详细信息

迷走神经支配人体的内脏器官,其传出纤维激活后可释放乙酰胆碱调节器官功能,而传入纤维能感知器官中机械和化学信号,并将其传入中枢,这种双向交流使得神经中枢能够反馈性调节器官功能。在呼吸系统中,迷走神经调节气道张力、血流供应、黏液分泌及呼吸型式。近来发现,迷走神经与免疫系统产生交互作用,在肺部疾病的发病机制中发挥重要作用,如哮喘、慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)、急性呼吸窘迫综合征(acute respirtory distress sydrome,ARDS)、肺纤维化和肺癌。在疾病状态下,多种细胞释放的细胞因子、化学因子和其他介质激活迷走神经,将免疫信息传到中枢,从而改变病程。激活迷走神经还可以释放神经肽调节免疫细胞的活动,并通过胆碱能抗炎通路控制肺部炎症,因此了解迷走神经在神经免疫反应中的作用对于肺部疾病的临床治疗有着重要意义。

关键词：迷走神经炎症肺神经免疫

Current role and future perspectives of artificial intelligence in echocardiography

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World Journal of Cardiology 2023年第6期15卷 284-292页

作者： rafael Vidal-perez Julia Grapsa Alberto Bouzas-Mosquera Ricardo Fontes-Carvalho Jose Manuel Vazquez-Rodriguez Servicio de Cardiología Unidad de Imagen y Función CardíacaComplexo Hospitalario Universitario A Coruña Centro de Investigación Biomédica en Red-Instituto de Salud Carlos ⅢA Coruña 15006Spain Department of Cardiology Guys and St Thomas NHS TrustLondon SE17EHUnited Kingdom Cardiology Department Centro Hospitalar de Vila Nova de Gaia/EspinhoVilanova de Gaia 4434-502Portugal Cardiovascular R&D Centre-UnIC@RISE Department of Surgery and PhysiologyFaculty of Medicine of the University of PortoPorto 4200-319Portugal Servicio de Cardiología Complexo Hospitalario Universitario A CoruñaA Coruña 15006Spain

Echocardiography is an essential tool in diagnostic cardiology and is fundamental to clinical care.Artificial intelligence(AI)can help health care providers serving as a valuable diagnostic tool for physicians in the field of echocardiography specially on the automation of measurements and interpretation of results.In addition,it can help expand the capabilities of research and discover alternative pathways in medical management specially on prognostication.In this review article,we describe the current role and future perspectives of AI in echocardiography.

关键词： Echocardiography Artificial intelligence Machine learning Deep learning Prognosis

ISCHEMIA trial:How to apply the results to clinical practice

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World Journal of Cardiology 2021年第8期13卷 237-242页

作者： rafael Vidal-perez Alberto Bouzas-Mosquera Jesus Peteiro Jose Manuel Vazquez-Rodriguez Servicio de Cardiologia Unidad de Imagen y Funcion CardiacaComplexo Hospitalario Universitario A Coruna(CHUAC)Centro de Investigacion Biomedica en Red(CIBERCV)-Instituto de Salud Carlos IIIA Coruna 15006Spain Servicio de Cardiología Complexo Hospitalario Universitario A CoruñaA Coruña 15006Spain

During the last years two questions have been continuously asked in chronic coronary syndromes:(1)Do revascularization procedures(coronary artery bypass grafting or percutaneous coronary intervention)really improve symptoms of angina?and(2)Do these techniques improve outcomes,i.***.do they prevent new myocardial infarction events and cardiovascular death?Therefore,there was a need for a large definitive trial.This study was the ISCHEMIA trial,a large,multicentric trial sponsored by the National Heart,Lung,and Blood Institute.The main trial compared coronary revascularization and optimal medical treatment(OMT)vs OMT alone in 5179 patients enrolled after a stress test.During a median 3.2-year follow-up,318 primary outcome events occurred;the adjusted hazard ratio for the invasive strategy as compared with the conservative strategy was 0.93(95%confidence interval 0.80-1.08,P=0.34).The ISCHEMIA trial deeply disrupted many of our prior attitudes regarding management strategies for patients with stable coronary artery disease.The findings underscore the benefits of disease-modifying OMT for stable coronary artery disease patients.The main purposes of ischemia assessment before this trial were:Diagnostic purposes,assessment of outcome,and adding to decision-making processes.Obviously,this changed after the trial results.The results of ISCHEMIA might challenge the current diagnostic approach for stable angina patients recommended in the last European Society of Cardiology guidelines on chronic coronary disease that were based on studies published before the ISCHEMIA trial.In this editorial we propose our approach based on the ISCHEMIA study and the pretest probability for a positive test in patients with chronic coronary syndromes.

关键词： Stable angina Chronic coronary syndrome ISCHEMIA Stress testing Therapy Diagnosis