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Improvements in tribological and anticorrosion performance of porous Ti–6Al–4V via PEO coating

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Friction 2021年第5期9卷 1303-1318页

作者： C.Garcia-Cabezón M.L.rodríguez-Méndez V.AmigóBorrás r.Bayón C.Salvo-Comino C.Garcia-Hernandez F.Martin-Pedrosa Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain BioecoUVA research Institute Universidad de ValladolidValladolid 47011Spain Group UVASEnS Escuela de Ingenierías IndustrialesUniversidad de ValladolidValladolid 47011Spain Instituto de Tecnología de Materials Univesitat Politécnica de ValenciaValencia 46022Spain Tribology Unit Fundación IK4-TeknikerEibar 20600Spain

Medical implants manufactured using biomaterial Ti–6Al–4V exhibit some *** higher elastic modulus than that of natural bone can cause stress shielding *** can be avoided using Ti–6Al–4V with pores in the implant ***,poor corrosion and tribocorrosion behaviors are yielded because of the large area exposed to the *** mitigate both issues,coating technologies can be *** plasma electrolytic oxidation(PEO)process is a cost‐effective process that has been used successfully in nonporous Ti *** this study,two PEO coatings with different amounts of Ca/P are ***,reports regarding their application in porous materials are *** effects of PEO treatments on corrosion and tribocorrosion in Ti–6Al–4V powder metallurgy are analyzed *** porous materials provide an efficient surface for PEO coatings,as demonstrated via scanning electron microscopy(SEM)and atomic force microscopy(AFM),and the porosity of the substrates improved the adherence of the *** corrosion resistance measured via electrochemical impedance spectroscopy confirmed the beneficial effect of the coatings,particularly for long exposure *** lower roughness,small pore size,and more compact film observed in the PEO–Ca/P sample resulted in favorable tribological and corrosion properties.

关键词： Ti‐based alloys corrosion tribocorrosion surface modification

Diagnostic and therapeutic challenges of gastrointestinal angiodysplasias: A critical review and view points

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World Journal of Gastroenterology 2019年第21期25卷 2549-2564页

作者： Diego García-Compeán ángel n Del Cueto-Aguilera Alan r Jiménez-rodríguez José A González-González Héctor J Maldonado-Garza Gastroenterology Service and Department of Internal Medicine Faculty of Medicine University Hospital "Dr. José E. González"Universidad Autónoma de Nuevo León

Gastrointestinal angiodysplasias (GIADs), also called angioectasias, are the most frequent vascular lesions. Its precise prevalence is unknown since most of them are asymptomatic. However, the incidence may be increasing since GIADs affect individuals aged more than 60 years and population life expectancy is globally increasing worldwide. They are responsible of about 5% to 10% of all gastrointestinal bleeding (GIB) cases. Most GIADs are placed in small bowel, where are the cause of 50 to 60% of obscure GIB diagnosed with video capsule endoscopy. They may be the cause of fatal severe bleeding episodes;nevertheless, recurrent overt or occult bleeding episodes requiring repeated expensive treatments and disturbing patient’s quality-of-life are more frequently observed. Diagnosis and treatment of GIADs (particularly those placed in small bowel) are a great challenge due to insidious disease behavior, inaccessibility to affected sites and limitations of available diagnostic procedures. Hemorrhagic causality out of the actively bleeding lesions detected by diagnostic procedures may be difficult to establish. no treatment guidelines are currently available, so there is a high variability in the management of these patients. In this review, the epidemiology and pathophysiology of GIADs and the status in the diagnosis and treatment, with special emphasis on small bowel angiodysplasias based on multiple publications, are critically discussed. In addition, a classification of GIADs based on their endoscopic characteristics is proposed. Finally, some aspects that need to be clarified in future research studies are highlighted.

关键词： Angiodysplasias Angioectasias Vascular malformations Epidemiology Pathogenesis Endoscopic treatment Somatostatin analogues

X-ray diffraction analysis by rietveld refinement of FeAl alloys doped with terbium and its correlation with magnetostriction

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Journal of rare Earths 2023年第8期41卷 1217-1224,I0004页

作者： J.S.Uribe-Chavira G.Herrera-Pérez C.r.Santillán.rodríguez r.J.Sáenz-Hernández J.A.Matutes-Aquino M.C.Grijalva-Castillo Materials Physics Department Centro de Investigación en Materiales AvanzadosS.C.Miguel de Cervantes 120Chihuahua31136ChihMexico COnACYT–Centro de Investigación en Materiales Avanzados S.C.Miguel de Cervantes 120Chihuahua31136ChihMexico

Fe_(81)Al_(19) polycrystalline alloys doped with Tb(0-0.25 at%) were obtained by arc *** introduction of Tb favors the formation of columnar grains in the micro structure of the alloys,which develops a texture in the [100]crystal *** examination shows that the alloys are composed in great proportion by the disordered body-centered cubic(bcc),A2 phase and by a small proportion of the ordered bcc,B2 *** a consequence of doping with Tb,the lattice parameter increases,so the calculated apparent crystallite size increases,indicating a decrease in dislocation density and therefore in *** change in the magnetostriction with the magnetic field,dλ_(T)/dH,is directly related to strain anisotropy that can favor the iron easy magnetization axis on the [100] *** increase in total magnetostriction is found in the doped alloys with a maximum of 90 × 10^(-6) at 300 K for the alloy containing 0.027 at% *** enhancement is a threefold value of the undoped alloy,which is attributed to the smaller maximum strain value and the preferential orientation formation by the columnar grains.

关键词： FeAl alloy Magnetostriction rietveld refinement Microstrains Preferred orientation rare earths

novel electrode structure in a DBD reactor applied to the degradation of phenol in aqueous solution

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Plasma Science and Technology 2017年第7期19卷 71-84页

作者： Antonio MErCADO-CABrErA rosendo PE?A-EGUILUZ régulo LóPEZ-CALLEJAS Bethsabet JArAMILLO-SIErrA raúl VALEnCIA-ALVArADO Benjamín.rodríguez-MénDEZ Arturo E MU?OZ-CASTrO Instituto nacional de Investigaciones nucleares Plasma Physics Laboratory Tecnológico de Estudios Superiores de Tianguistenco

Phenol degradation experimental results are presented in a similar wastewater aqueous solution using a non-thermal plasma reactor in a coaxial dielectric barrier discharge. The novelty of the work is that one of the electrodes of the reactor has the shape of a hollow screw which shows an enhanced efficiency compared with a traditional smooth structure. The experimentation was carried out with gas mixtures of 90% Ar-10% O2, 80% At-20% 02 and 0% Ar-100% 02. After one hour of treatment the removal efficiency was 76%, 92%, and 97%, respectively, assessed with a gas chromatographic mass spectrometry technique. For both reactors used, the ozone concentration was measured. The screw electrode required less energy, for all gas mixtures, than the smooth electrode, to maintain the same ozone concentration. On the other hand, it was also observed that in both electrodes the electrical conductivity of the solution changed slightly from ,-0.0115 S m^-1 up to -0.0430 S m^-1 after one hour of treatment. The advantages of using the hollow screw electrode structure compared with the smooth electrode were：（1） lower typical power consumption, （2） the generation of a uniform plasma throughout the reactor benefiting the phenol degradation, （3） a relatively lower temperature of the aqueous solution during the process, and （4） the plasma generation length is larger.

关键词： DBD gas discharges removal organic compounds discharge in liquids

Design of a novel Exoskeleton with Passive Magnetic Spring Self-locking and Spine Lateral Balancing

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Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon F.rodríguez-León Betsy D.M.Chaparro-rico Daniele Cafolla Francesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico Department of Mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly Faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTEr University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PrrrP(P-Prismatic;r-revolute)kinematic chain with 5 passive Degrees of Freedom(DoF).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight *** paper reports specific models and simulations to demonstrate the feasibility and effectiveness of the proposed *** experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling *** obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Generating oligodendroglia from adult mesenchymal cells for transplantation:cell reprogramming or direct lineage conversion?

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neural regeneration research 2023年第7期18卷 1493-1494页

作者： Jorge Pascual-Guerra JoséA.rodríguez-navarro Carlos L.Paíno Service of neurobiology-research Ramón y Cajal University Hospital-IRYCISMadridSpain Department of Cellular Biology Complutense UniversityMadridSpain

Cell replacement therapy has long been proposed as a treatment for the damaged nervous *** of the most challenging aspects of such a strategy,however,is finding sources of donor cells for *** neural cells are rarely an option as every cell in the nervous system has a defined function that would be lost if that cell was to be *** possibility would be sourcing precursor or differentiated cells from fetal tissues;however,aside from ethical issues,heterologous cells are at risk of immunological rejection in the long *** improvements over the past 15 years have led to the possibility that autologous non-neural cells could be used for cell transplantation through their conversion into neural derivatives.

关键词： neural programming removed

Kinetic analysis via mathematical modeling for ferrous iron oxidation in a class of SBr-type system

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2472-2480页

作者： Edgar nTec-Caamal refugio rodríguez-Vázquez Luis GTorres-Bustillos ricardo Aguilar-López Center for research and Advanced Studies of the national Polytechnic Institute Av.Instituto Politécnico Nacional No.2508Colonia San Pedro ZacatencoC.P.07360 Ciudad de México D.F.Mexico Interdisciplinary Professional Unit of Biotechnology-national Polytechnic Institute(UPIBI-IPn) Acueducto s/nLa Laguna TicománGustavo A.Madero07340Ciudad de MéxicoMexico

This paper analyses the oxidation of ferrous iron via chemical and biological means in a class of Sequential Batch reactors(SBr-type).For this,a kinetic model for the study of iron oxidation system is proposed,followed by a parametric sensitivity analysis and a bifurcation analysis,which allow selecting the most influential kinetic parameters in order to ensure a suitable prediction capacity of the mathematical *** system consists of two SBr bioreactors,the first being used to produce hydrogen peroxide(H2O2)that is fed to a second reactor where the iron oxidation is carried out by chemical–biological *** predictions were compared with experimental data for the production of H2O2 and for ferrous iron oxidation,finding suitable correlation coefficients(r2 n 0.98)for each state *** bifurcation analysis showed the trajectories of the main variables,such as,biomass,H2O2 and ferrous iron,under the change of the most influential kinetic *** analysis demonstrates the usefulness of the constructed model to predict the kinetic behaviour of the SBr-type process.

关键词： Bifurcation analysis Hydrogen peroxide Iron oxidation Modeling Simulation

Politicizing responsible Innovation:responsibility as Inclusive Governance

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International Journal of Innovation Studies 2017年第1期1卷 20-36页

作者： Andoni Eizagirre Hannot rodríguez Andoni Ibarra Department of Social Sciences Faculty of Humanities and EducationMondragon UniversityDorleta auzoa z/g20540 EskoriatzaSpain Department of Philosophy Faculty of ArtsUniversity of the Basque Country UPV/EHUPaseo de la Universidad 501006 Vitoria‐GasteizSpain Department of Logic and Philosophy of Science Faculty of EducationPhilosophy and AnthropologyUniversity of the Basque Country UPV/EHUTolosa Ave.7020018 Donostia‐San SebastiánSpain

This paper aims to provide the historical and conceptual bases underlying the inclusionary transition of European innovation policy,and critical analysis of the difficulties relating to the political nature of this *** the 50s and 60s of last century,linear innovation models operated on the basis of a clear division of roles among the different actors in innovation and fundamentally economistic‐based *** following decades saw innovation policies progressively recognize the multi‐dimensional and complex nature of innovation and the need to make adjustments,but always in explicit response to the competitiveness *** recent rrI(responsible research and Innovation)strategy within the European Union,in contrast,demands opening up the whole innovation process(including values and motivations)to collective decision,i.e.,approaching responsible innovation as inclusive *** paper appraises this important development primarily on the basis of in‐depth analysis of the main policy literature on innovation,and also on the grounds of related academic *** a result,we conclude that the bid for collaboration models cohabits constitutively with another set of dynamics aimed at strengthening centralized and prescriptive forms of *** other words,that inclusionary or political eagerness represented through rrI must grapple with the strategic imperative of competitiveness and economic ***,fundamental tension exists,which should be elucidated in light of the objectives,demands and considerations that are integrated,and cease to be integrated,in innovation dynamics and trajectories.

关键词： Inclusive innovation responsible research and Innovation(rrI) Competitiveness Institutional ecosystem

Meckel's diverticulum diagnosis by video capsule endoscopy: A case report and review of literature

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World Journal of Clinical Cases 2018年第14期6卷 791-799页

作者： Diego García-Compeán Alan r Jiménez-rodríguez Angel n Del Cueto-Aguilera Gilberto Herrera-Quinones José A González-González Héctor J Maldonado-Garza Gastroenterology Service and Department of Internal Medicine Faculty of Medicine University Hospital "Dr. José E. González" Universidad Autónoma de Nuevo León Monterrey 64700 Nuevo León México

BACKGrOUnD Meckel’s diverticulum （MD） occurs predominantly in chil-dren and adolescents. It is rarely diagnosed in adults. Preoperative diagnosis is diffcult due to low sensitivity of the radiological imaging studies. The role of video capsule endoscopy （VCE） in the diagnosis of MD is unknown, and the endoscopic patterns are not defned. We will describe four of our cases of MD evaluated with VCE and make a review of the literature focusing on the endoscopic *** SUMMArYWe present four cases of MD confirmed by surgery. They were all adult males with ages going from 18 to 50 years, referred to our service from 2004 to 2018, due to obscure gastrointestinal bleeding （OGIB）. TheyGarcía-Compeán D et al . Merckel’s diverticulum diagnosis by VCEhad a history of 1 mo to 10 years of overt and occult bleeding episodes. Laboratory blood test showed an iron-deficiency anemia from 4 to 9 g/dL of hemoglo-bin that required multiple hospitalizations and blood transfusions in all cases. repeated upper digestive endoscopies and colonoscopies were negative. Small bowel was examined with VCE, which revealed double lumen images in all cases, one with polyps and three with circumferential ulcers in the diverticulum. However, based on VCE findings, preoperative diagnosis of MD was suggested only in two patients. Capsule was retain-ed in one patient, which was recovered with surgery. The anatomopathological report revealed ulcerated ectopic gastric mucosa in all *** is useful for the diagnosis of MD. However, endo-scopic characteristics must be recognized in order to establish preoperative diagnosis.

关键词： Meckel’s diverticulum Endoscopic features Video capsule endoscopy Wireless capsule endoscopy review Case report