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

Blood biomarkers of Alzheimer’s disease:important considerations for use in clinical practice

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Neural regeneration research 2025年第1期20卷 205-206页

作者： Sarah Fullam Sean o’Dowd Antoinette o’connor Department of Neurology Tallaght University HospitalDublinIreland Academic Unit of Neurology Trinity College DublinIreland

Introduction:Fluid and positron emission tomography(PET)biomarkers that enable the detection of the hallmark proteins of Alzheimer’s disease(AD)(amyloid and tau)have revolutionized our approach to the diagnosis of *** evolution of AD diagnostic criteria to include biological characterization(Alzheimer’s Association Working Group,2023)provides an appropriate framework to reduce levels of clinico-pathologic mismatch and improve in-vivo diagnostic *** the therapeutic landscape for neurodegenerative disease evolves,it is increasingly incumbent on clinicians to provide timely,and pathologically precise diagnoses for ***,the expensive and invasive nature of these tests limits their scalability.

关键词： Blood Alzheimer diagnosis

Insights into transferal to fractal space modeling:delayed forced Helmholtz-Duffing oscillator with the non-perturbative approach

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communications in Theoretical Physics 2025年第1期77卷 11-22页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The damped Helmholtz-Duffing oscillator is a topic of great interest in many different fields of study due to its complex *** transitioning from conventional continuous differential equations to their fractal counterparts,one gains insights into the system's response under new mathematical *** paper presents a novel method for converting standard continuous differential equations into their fractal *** conversion occurs after the nonlinear system is transformed into its linear *** analyses show that there are several resonance sites in the fractal system,which differ from the one resonance point found in the continuous *** important finding is that the fractal system loses some of its stabilizing power when decaying behavior is transformed into a diffuse ***,a decrease in the fractal order in resonance settings shows a stabilizing impact,highlighting the dynamics'complexity inside fractal *** endeavor to convert to fractals is a revolutionary technique that is being employed for the first time.

关键词： nonlinear oscillations Helmholtz-Duffing oscillator forced with delay effect non-perturbative methodology stability outlines new perspectives on transferal to fractal space modeling

Products of Distributions,conservation Laws and the Propagation of δ'-Shock Waves

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chinese Annals of Mathematics,Series B 2012年第3期33卷 367-384页

作者： carlos orlando r. sarrico cMAF University of LisbonAv.Prof.Gama Pinto 21649-003Portugal

This paper contains a study of propagation of singular travelling waves u（x, t） for conservation laws ut ＋ [Ф（u）]x = ψ（u）, where Ф, ψ are entire functions taking real values on the real axis. conditions for the propagation of wave profiles β ＋ mδ and β ＋ mδt are presented （β is a real continuous function, m ≠ 0 is a real number and δ＇ is the derivative of the Dirac measure 5）. These results are obtained with a consistent concept of solution based on our theory of distributional products. Burgers equation ut ＋（u2/2）x = 0, the iffusionless Burgers-Fischer equation ut ＋ a（u2/2）x = ru（1 - u/k） with a, r, k being positive numbers, Leveque and Yee equation ut ＋ ux = μx（1 - u）（u - u/k） with μ ≠ 0, and some other examples are studied within such a setting. A ＂tool box＂ survey of the distributional products is also included for the sake of completeness.

关键词： conservations laws Travelling waves δ^-shock waves δ-shock waves δ-solitons Propagation of distributional wave profiles

Neuroinflammation revisited through the microglial lens

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Neural regeneration research 2025年第7期20卷 1989-1990页

作者： renato Socodato João B.relvas Institute of research and Innovation in Health(i3S)and Institute for Molecular and cell Biology(IBMc) University of PortoPortoPortugal Department of Biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(cNS)and the immune *** exploration is particularly significant in understanding microglia,the cNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural regeneration research 2025年第9期20卷 2596-2597页

作者： christopher J.o’connell Matthew J.robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle college of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(capizzi et al.,2020).

关键词： sustained orange dynamic

creeping fat and gut microbiota in crohn’s disease

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World Journal of Gastroenterology 2025年第1期31卷 16-23页

作者： Ana EV Quaglio Daniéla o Magro Marcello Imbrizi Ellen cS De oliveira Luiz c Di Stasi Ligia Y Sassaki Verum Ingredients Botucatu Technology ParkBotucatu 18605-525São PauloBrazil Department of Surgery Faculty of Medical SciencesState University of CampinasCampinas 13083-970São PauloBrazil Department of Gastroenterology Faculty of Medical SciencesUniversity of CampinasCampinas 13083-970São PauloBrazil Department of Internal Medicine Medical SchoolSão Paulo State UniversityBotucatu 18618-686São PauloBrazil Department of Biophysics and Pharmacology Institute of BiosciencesSão Paulo State UniversityBotucatu 18618-689São PauloBrazil

In this article,we explored the role of adipose tissue,especially mesenteric adipose tissue and creeping fat,and its association with the gut microbiota in the pathophysiology and progression of crohn’s disease(cD).cD is a form of inflammatory bowel disease characterized by chronic inflammation of the gastrointestinal tract,influenced by genetic predisposition,gut microbiota dysbiosis,and environmental *** microbiota plays a crucial role in modulating immune response and intestinal inflammation and is associated with the onset and progression of ***,visceral adipose tissue,particularly creeping fat,a mesenteric adipose tissue characterized by hypertrophy and fibrosis,has been implicated in cD pathogenesis,inflammation,and *** bacteria from the gut microbiota may translocate into mesenteric adipose tissue,contributing to the formation of creeping fat and influencing cD *** creeping fat may be a protective barrier against bacterial invasion,its expansion can damage adjacent tissues,leading to *** gut microbiota through interventions such as fecal microbiota transplantation,probiotics,and prebiotics has shown potential in managing ***,more research is needed to clarify the mechanisms linking gut dysbiosis,creeping fat,and cD progression and develop targeted therapies for microbiota modulation and fat-related complications in patients with cD.

关键词： creeping fat Mesenteric adipose tissue Gut microbiota crohn’s disease Inflammatory bowel disease

cryopreservation of bovine sperm causes single‑strand DNA breaks that are localized in the toroidal regions of chromatin

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Journal of Animal Science and Biotechnology 2025年第1期16卷 92-106页

作者： Jordi ribas‑Maynou rodrigo Muiño carolina Tamargo Marc Yeste Biotechnology of Animal and Human reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaS17003 GironaSpain Unit of cell Biology Department of BiologyFaculty of SciencesUniversity of GironaS17003 GironaSpain Present Address:Unit of cell Biology and Medical Genetics Department of Cell BiologyPhysiology and ImmunologyAutonomous University of BarcelonaS08193 BellaterraSpain Department of Animal Pathology Faculty of Veterinary MedicineUniversity of Santiago de CompostelaS15705 LugoSpain Department of Animal Selection and reproduction The Regional Agri-Food Research and Development Service of Asturias(SERIDA)S33394 GijónSpain catalan Institution for research and Advanced Studies(IcrEA) S08010 BarcelonaSpain

Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial *** freeze-thawing is known to impair sperm DNA integrity,whether the damage induced consists of single-(SSB)or double-strand breaks(DSB)has not been *** addition,no previous study has addressed if DNA breaks preferentially reside in specific genome regions such as those forming the toroid linker regions,or are rather spread throughout the regions linked to *** main aim of the present work,therefore,was to elucidate the type and localization of the DNA damage generated by cryopreservation and to evaluate its impact on artificial insemination outcomes in *** The incidence of SSB and DSB was evaluated in 12 ejaculates before and after cryopreservation with the comet assay,and the localization of the DNA breaks was assessed using pulsed-field gel electrophoresis(PFGE).Before cryopreservation,the incidence of SSB was 10.99%±4.62%and involved 20.56%±3.04%of sperm cells,whereas these figures significantly(Pcreased up to 34.11%±3.48%and 53.36%±11.00%in frozen-thawed *** contrast,no significant differences in the incidence of DSB were observed(P>0.990)before and after cryopreservation(before:incidence of 13.91%±1.75%of sperm DNA affecting 56.04%±12.49%of sperm cells;after:incidence of 13.55%±1.55%of sperm DNA involving 53.36%±11.00%of sperm cells).Moreover,PFGE revealed that the percentage of sperm DNA fragments whose length was shorter than a toroid(reater(Pr(27.00%±4.26%)than before freeze-thawing(15.57%±4.53%).These differences indicated that the DNA breaks induced by cryopreservation affect the regions condensed in protamines,which are structured in *** the other hand,in vivo fertility rates were associated to the incidence of SSB and DSB in frozen-thawed sperm(P=0.032 and P=0.005),but not w

关键词： cattle DNA damage Fertility Sperm Toroid linker regions