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Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based Medical Implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan I Međo Ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča Institute of nuclear Sci-ences-national Institute of the Republic of Serbia University of Belgrade11001BeogradSerbia Innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： H.HoSSEInI o.BALIlaSHAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： point source cylindrical cavity porous medium wave-field transformation stress concentration o353.4

Data-driven drug repositioning using olfactory omics profiles:challenges and perspectives in neurodegeneration

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neural Regeneration Research 2025年第7期20卷 1997-1998页

作者： Paz Cartas-Cejudo Adriana Cortés Mercedes lachén-Montes Elena Anaya-Cubero Joaquín Fernández-Irigoyen Enrique santamaría Clinical neuroproteomics Unit Proteomics PlatformNavarrabiomedHospitalario Universitario de Navarra(HUN)Universidad Pública de Navarra(UPNA)IdiSNANavarra Institute for Health ResearchPamplonaSpain

Data-driven drug repositioning using olfactory omics profiles-challenges and perspectives in neurodegeneration:neurodegenerative diseases are characterized by progressive degeneration and loss of neuronal function in the central nervous *** diseases are often characterized as proteinopathies,which are disorders primarily driven by the aggregation or misfolding of specific amyloid proteins within cells,leading to their dysfunction and eventual *** the gain-of-function hypothesis related to the aggregation of these proteins,recently,an alternative hypothesis regarding the loss-of-function of the soluble monomeric proteins during the process of aggregation into amyloids is gaining *** last event is called proteinopenia and refers to conditions characterized by a deficiency or decrease in the levels of specific soluble proteins in the body(Ezzat et al.,2023).It has been demonstrated that levels of soluble proteins involved in neurodegenerative diseases are decreased.

关键词： diseases drug amyloid

neurocircuit regeneration by extracellular matrix reprogramming

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neural Regeneration Research 2025年第8期20卷 2300-2301页

作者： Shengzhang Su Ian n.Levasseur Kimberly M.Alonge Department of Medicinal Chemistry University of WashingtonSeattleWAUSA Department of Chemistry University of WashingtonSeattleWAUSA Department of Medicine University of Washington Medicine Diabetes InstituteSeattleWAUSA

The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECM regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(Miyata et al.,2012),cation buffering(Moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECM indicates that this understudied medium is an active participant in both normal physiology and neurological diseases.

关键词： matrix programming

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

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neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto Doncel-Pérez Gabriel Guízar-sahagún Israel Grijalva-otero Hospital nacional de Parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain Medical Research Unit for neurological Diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Deduction and Validation of an Eulerian-Eulerian Model for Turbulent Dilute Two-Phase Flows by Means of the Phase Indicator Function-Disperse Elements Probability Density Function

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Chinese Journal of Chemical Engineering 2000年第3期8卷 189-202页

作者： sa.tia.o laín Ricardo Aliod MVT-UST Fachbereich Ingenieurwissenschaften Martin-Luther-UniversitatHalle-WittenbergD-06099Halle(Saale)GermanyFluid Mechanica DepartmentE.U.Politecnica de Huesca.University of ZaragozaCarretera Zaragoza km.6722071 HuescaSpain

A statistical formalism overcoming some conceptual and practical difficulties arising in existing two-phase flow (2PHF) mathematical modelling has been applied to propose a model for dilute 2PHF turbulent Hows. Phase interaction terms with a clear physical meaning enter the equations and the formalism provides some guidelines for the avoidance of closure assumptions or the rational approximation of these terms. Continuous phase averaged continuity, momentum, turbulent kinetic energy and turbulence dissipation rate equations have been rigorously and systematically obtained in a single step. These equations display a structure similar to that for single-phase flows. It is also assumed that dispersed phase dynamics is well described by a probability density function (pdf) equation and Eulerian continuity, momentum and fluctuating kinetic energy equations for the dispersed phase are deduced. An extension of the standard k-e turbulence model for the continuous phase is used. A gradient transport model is adopted for the dispersed phase fluctuating fluxes of momentum and kinetic energy at the non-colliding, large inertia limit. This model is then used to predict the behaviour of three axisymmetric turbulent jets of air laden with solid particles varying in size and concentration. Qualitative and quantitative numerical predictions compare reasonably well with the three different sets of experimental results, studying the influence of particle size, loading ratio and flow confinement velocity.

关键词： two-phase flow turbulence phase indicator function pdf ensemble average jet

Single-step nano-engineering of multiple micro-rough metals via anodization

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nano Research 2023年第1期16卷 1320-1329页

作者： Divya Chopra tianqi Guo sašo Ivanovski Karan Gulati The University of Queensland School of DentistryHerston QLD 4006Australia

Anodization is a cost-effective technique to nano-engineer various metals,however,optimizations have been mostly restricted to Al and Ti,and for easy to manage polished and flat substrates,limiting industrial ***,we aim at standardizing and simplifying anodization of ten metals,attempting to make metal nano-engineering more *** a world-first attempt,we synthesize a standard electrolyte to fabricate controlled nanostructures on various metals,taking a close look at the influence of the substrate topography,electrolyte composition,and electrolyte aging(repeated use of same electrolyte)towards designing a standard nano-engineering *** of curved substrates(metal wires)with micro-roughness allows for ease of industrial translation across various *** study is a step closer to standardizing anodization and fabrication of controlled nanotopography on various metallic surfaces,while maintaining scalability and ease of use.

关键词： electrochemical anodization nanopores nanotubes metal metal oxide nanostructures

A new series of environment-friendly reddish inorganic pigments based on AFeo_(3)(A=Ln,Y) with high nIR solar reflectance

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Journal of Materiomics 2021年第5期7卷 1061-1073页

作者： Maria Fortuño-Morte Pablo Serna-Gallén Héctor Beltrán-Mir Eloísa Cordoncillo Departamento de Química Inorgánica y orgánica Universitat Jaume IAv.Sos Baynat s/n12071Castellóde la PlanaSpain

Environment-friendly pigments based on AFeo_(3)(A=la,Pr,nd,Sm,Gd,Tb,Y or Yb)with high nearinfrared(nIR)reflectance were synthesised by a coprecipitation method at 1200℃.The Rietveld refinement analysis showed single-phase orthorhombic perovskite for all *** pigments,which showed reddish hues,offered good colour stability after mixing these pigments in powder form with siloxane transparent paint and two different *** powderepaint mixtures produced with GdFeo_(3),TbFeo_(3) and YFeo_(3) pigments have the highest nIR solar reflectance,reaching values of R=50%.The temperature shielding studies conducted using TbFeo_(3) pigmentepaint mixture for a roof coating yielded a reduction of 3.2℃ in comparison to a commercial ***,the glazes that were pigmented using GdFeo_(3),TbFeo_(3) and YFeo_(3) compositions also presented the most intense reddish colours.A study of the thermal and chemical stability of the pigment with the highest nIR solar reflectance showed good stability in both *** reddish pigments that were prepared can therefore be good candidates for use in different applications such as cool pigments or pigments for ceramic glazes at high temperatures.

关键词： High nIR reflectance Cool pigment Reddish pigment Environment-friendly Coprecipitation

Progress and challenges in the comprehensive management of chronic viral hepatitis: Key ways to achieve the elimination

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World Journal of Gastroenterology 2021年第26期27卷 4004-4017页

作者： Fátima Higuera-de la Tijera Alfredo Servín-Caamaño Luis Servín-Abad Department of Gastroenterology and Hepatology Hospital General de MéxicoMexico City 06726Mexico Department of Internal Medicine Hospital General de MéxicoMexico City 06726Mexico Department of Gastroenterology Saint Cloud HospitalSaint CloudMN 56303United States

Chronic viral hepatitis is a significant health problem throughout the world,which already represents high annual *** 2040,chronic viral hepatitis due to virus B and virus C and their complications cirrhosis and hepatocellular carcinoma will be more deadly than malaria,vitellogenesis-inhibiting hormone,and tuberculosis *** this review,we analyze the global impact of chronic viral hepatitis with a focus on the most vulnerable groups,the goals set by the World Health organization for the year 2030,and the key points to achieve them,such as timely access to antiviral treatment of direct-acting antiviral,which represents the key to achieving hepatitis C virus ***,we review the strategies to prevent transmission and achieve control of hepatitis B ***,we address the impact that the coronavirus disease 2019 pandemic has had on implementing elimination strategies and the advantages of implementing telemedicine programs.

关键词： Hepatitis C Hepatitis B Vaccination Elimination program Telemedicine Direct antiviral agents