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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 *** implementation involves three main components:numerical analysis using the Finite Element Method(FEM),sensitivity analysis using an Adjoint method and an optimization *** 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 *** 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 *** topological optimization method used is based on the SIMP-Solid IsotropicMaterial with Penalization *** 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 *** 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

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 *** 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 ***,EUS has a very high negative predictive value and thus EUS can reliably exclude pancreatic *** 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 *** 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 *** 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： Endosonography Pancreatic neoplasms Endoscopy Diagnosis Neoplasm Staging Therapeutics

Driving Factors for Forest Fire Occurrence in Durango State of Mexico:A Geospatial Perspective

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Chinese Geographical Science 2010年第6期20卷 491-497页

作者： Diana Avila-Flores marin Pompa-Garcia Xanat Antonio-Nemiga Dante A Rodriguez-Trejo Eduardo Vargas-perez Javier Santillan-perez Forestry Division University of Chapingo Faculty of Forestry Juarez University of the State of DurangoRio Papaloapan and Durango Blvd Faculty of Geography Autonomous University of Mexico StateCerro de Coatepec s/nCiudad Universitaria

Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management *** the driving factors and understanding the contribution of each factor are essential for the management of forest fire *** objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,*** this purpose,data from forest fire records for a five-year period were *** spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square *** show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory *** addition,vegetation type and precipitation are also the main driving *** fitting model indicates obvious link between the *** fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire *** regulation of human activities is a key strategy for forest fire prevention.

关键词： forest fire Geographically Weighted Regression(GWR) land use forest management Durango State Mexico

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

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

Low-cost disordered carbons for Li/S batteries： A high- performance carbon with dual porosity derived from cherry pits

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Nano Research 2018年第1期11卷 89-100页

作者： Celia Hernandez-Rentero rafael Cordoba Noelia Moreno Alvaro Caballero Julian Morales Mara Olivares-marin Vicente Gomez-Serrano Dpto. Ouimica Inorgdnica e Ingenierfa Quimica Instituto de Quimica Fina y Nanoqufmica Universidad de C6rdoba 14071 C6rdoba Spain Dpto. Quimica Inorg6nica Facultad de Ciencias Universidad de Extremadura 06006 Badajoz Spain

A micro- and mesoporous carbon obtained from cherry pit waste and activated with HBPO4 acid has been studied as the sulfur host for Li/S batteries. The carbon has a high specific surface area of 1,662 m2·g-1 （SBET） and micropore and mesopore volumes of 0.57 and 0.40 cm3·g-1, respectively. The S/C composite, with a sulfur content of 57% deposited by the disproportionate reaction of a SaO2- solution in an acid medium without an additional heating step above the S melting point, delivers an initial specific capacity of 1,148 mah·g-1 at a current of C/16. It also has a high capacity retention of 915 mAh·g-1 after 100 cycles and a Coulombic efficiency close to 100%. The good performance of the composite was also observed under higher current rates and long-term cycling tests. The capacities delivered by the cell after 200 cycles were 707 and 410 mAh·g-1 at C/2 and 1C （1C = 1,675 mA·g-1）, respectively, maintaining the high Coulombic efficiency. The overall electrochemical response of this carbon as the sulfur matrix is among the best reported so far among the other biomass-derived carbons, probably because of the micro- and mesopore system formed upon activation.

关键词： activated carbon agricultural waste cherry stone sulfur composite lithium-sulfur batteries

Unconditional Bound-Preserving and Energy-Dissipating Finite-Volume Schemes for the Cahn-Hilliard Equation

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Communications in Computational Physics 2023年第8期34卷 713-748页

作者： rafael Bailo Jose A.Carrillo Serafim Kalliadasis Sergio P.perez Mathematical Institute University of OxfordUK Univ.Lille CNRSUMR 8524-Laboratoire Paul PainleveFrance Department of Chemical Engineering Imperial College LondonUK Department of Mathematics Imperial College LondonUK

We propose finite-volume schemes for the Cahn-Hilliard equation which unconditionally and discretely preserve the boundedness of the phase field and the dissipation of the free *** numerical framework is applicable to a variety of free-energy potentials,including Ginzburg-Landau and Flory-Huggins,to general wetting boundary conditions,and to degenerate *** central thrust is the upwind methodology,which we combine with a semi-implicit formulation for the freeenergy terms based on the classical convex-splitting *** extension of the schemes to an arbitrary number of dimensions is straightforward thanks to their dimensionally split nature,which allows to efficiently solve higher-dimensional problems with a simple *** numerical schemes are validated and tested through a variety of examples,in different dimensions,and with various contact angles between droplets and substrates.

关键词： Cahn-Hilliard equation diffuse interface theory gradient flow finite-volume method bound preservation energy dissipation

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 *** is a rapidly evolving transdisciplinary field which integrates many elements to develop algorithms that aim to simulate human intuition,decision-making,and object *** overarching aims of AI in cardiovascular medicine are threefold:To optimize patient care,improve efficiency,and improve clinical *** 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 *** 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

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 *** images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential *** NPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** 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%),***,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 ***/absorbance measurements confirmed the presence of such ***,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 *** 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