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Surface Characterization and Cell Response of binary Ti-Ag Alloys with CP Ti as Material Control

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Journal of Materials Science & Technology 2012年第9期28卷 779-784页

作者： b.b. Zhang K.J. Qiu b.L. Wang L. Li Y.f. Zheng Center for biomedical Materials and Engineering Harbin Engineering University Harbin 150001 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

In this study, the surface passive films, dissolution behavior and biocompatibility of Ti-Ag alloys （with 5%, 10% and 20% Ag） were evaluated by X-ray diffraction （XRD） tests, electrochemical corrosion tests, X-ray photoelectron spectroscopy （XPS） tests, dissolution tests and in-vitro cytotoxicity tests. The surface films on the Ti-20Ag alloy are rich in Ti and much deficient in Ag with respect to alloy composition, as identified by XPS. Compared to CP Ti, Ti-SAg and Ti-20Ag alloys show larger impedances and lower capacitances, which can be associated with an increase of the passive layer thickness. Moreover, all Ti-Ag alloys exhibit negligible or low metal release in the test solutions. The in-vitro cytotoxicity results show Ti-Ag alloys seem to be as cytocompatible as CP Ti. from the viewpoint of surface passive film and cytotoxicity, Ti-SAg and Ti-20Ag are considered to be more suitable for dental applications.

关键词： Ti-Ag alloy Surfaces Electrochemical corrosion Cytotoxicity

A strategy for designing stable nanocrystalline alloys by thermo-kinetic synergy

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Journal of Materials Science & Technology 2020年第8期36卷 21-31页

作者： H.R.Peng b.S Liu f.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China Analytical and Testing Center Northwestern Polytechnical UniversityXi’an710072China

Aiming to design stable nanocrystalline(NC)materials,so far,it has been proposed to construct nanostructure stability maps in terms of thermodynamic parameters,while kinetic stabilization has seldom been considered,despite the synergy of thermodynamics and ***,the thermodynamically stabilized NC materials may be easily subjected to grain growth at high temperatures due to the weakly kinetic *** from the thermo-kinetic synergy,a stabilization criterion is proposed as a function of intrinsic solute parameters(*** activation energy for bulk diffusion and the segregation enthalpy),intrinsic solvent parameters(*** intrinsic activation energy for Gb migration and the Gb energy)and processing parameters(*** grain size,the temperature and the solute concentration).Using first-principles calculations for a series of combinations between fifty-one substitutional alloying atoms as solute atoms and fe atom as fixed solvent atom,it is shown that the thermal stability neither simply increases with increasing the segregation enthalpy as expected by thermodynamic stabilization,nor monotonically increases with increasing the activation energy for bulk diffusion as described by kinetic *** combination of thermodynamic and kinetic contributions,the current stabilization criterion evaluates quantitatively the thermal stability,thus permitting convenient comparisons among NC materials involved by various combinations of the solute atoms,the solvent atoms,or the processing *** of this thermo-kinetic stabilization criterion has been tested by current experiment results of fe-Y alloy and previously published data of fe-Ni,fe-Cr,fe-Zr and fe-Ag alloys,etc.,which opens a new window for designing NC materials with sufficiently high thermal stability and sufficiently small grain size.

关键词： Thermo-kinetic Synergy Criterion Thermal stability Nanocrystalline materials

Stabilizing nanograined fe-Cr alloy by Si-assisted grain boundary segregation

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Journal of Materials Science & Technology 2023年第3期134卷 223-233页

作者： X.f.Xu X.Y.Li b.Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Intentional solute segregation at grain boundary(Gb)can effectively stabilize the nanograined alloys by reducing the excess energy and mobility of Gb,but it usually works for binary alloys with sufficient Gb segregation ***,we found that the segregation of Cr can be enhanced in a nanostruc-tured fe-8Cr alloy with insufficient Gb segregation tendency through the interaction of another solute Si(1.0 wt.%).After surface mechanical grinding treatment and subsequent annealing,the nanograined fe-8Cr-1Si is more thermally stable than the nanograined fe-8Cr,which is mainly attributed to the Si-enhanced Cr segregation as observed by Super-X energy-dispersive X-ray spectroscopy(EDS)mapping *** the grain refinement to nanoscale,the thermal stability is further improved due to the in-crease of Cr content at Gbs and the precipitates formed at appropriate high *** present finding provides guidance for the development of advanced nanostructured ternary alloys.

关键词： Segregation Grain boundary fe-Cr-Si alloy Nanocrystalline Thermal stability

Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

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Journal of Materials Science & Technology 2024年第2期169卷 53-67页

作者： Y.b.Zhang S.J.Song f.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPfE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).by detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

Disseminated cutaneous leishmaniasis due to Leishmania(Leishmania) amazonensis in human immunodeficiency virus(HIV)-infected patients: A report of two cases

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Asian Pacific Journal of Tropical Medicine 2021年第6期14卷 281-284页

作者： Camila f Araújo Iara b N Oliveira Murilo b Silveira fátima Ribeiro-Dias Hospital de Doenças Tropicais Doutor Anuar Auad GoiâniaGoiásBrazil Laboratório de Imunidade Natural(LIN) Instituto de Patologia Tropical e Saúde PúblicaUniversidade Federal de GoiásGoiâniaGoiásBrazil

Rationale: Co-infection of human immunodeficiency virus(HIV) and Leishmania spp. has impact on clinical and therapeutic outcomes of leishmaniases. Most studies do not present the identification of Leishmania species causing American tegumentary leishmaniasis in co-infections. In the Americas, Leishmania(L.) Viannia(V.) braziliensis and L.(V.) guyanensis have been identified. Patient concerns: In this study, two cases of American tegumentary leishmaniasis in patients infected with HIV are described. Patients presented several lesions with rapid dissemination and mucosal involvement. Diagnosis: Disseminated cutaneous leishmaniasis caused by L. amazonensis was identified by molecular test. Interventions: The patients were treated with conventional therapies for HIV infection and American tegumentary leishmaniasis. Outcomes: In co-infection, the clinical manifestations are atypical and the treatment response can be impaired. Lessons: These cases show that HIV infection impacts L. amazonensis infection and point to the relevance of identifying Leishmania species, which can lead to a better patient management.

关键词： Leishmania amazonensis HIV Disseminated cutaneous leishmaniasis Case report

Unveiling the Residual Stresses,Local Micromechanical Properties and Crystallographic Texture in a Ti-6Al-4V Weld Joint

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 997-1006页

作者： b.Mehdi R.badji V.Ji b.Alili D.bradai W.bedjaoui f.Deschaux-beaume f.brisset Laboratoire de Physique Des Matériaux Facul téde PhysiqueUniversitéDes Sciences Et de La Technologie Houari Boumediene16111 AlgerAlgérie Research Center in Industrial Technologies CRTI P.O.Box64CheragaAlgeria ICMMO/SP2M UniversitéParis-Saclay LMGC University of MontpellierCNRSMontpellierFrance

In this work,the micromechanical properties,crystallographic texture,welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4V alloy tungsten inert gas weld *** was found that the welding process affected the Young modulus and microhardness values in bothαandβphases in the different regions of the weld *** highest microhardness and Young modulus values of a phase were recorded in the heat-affected zone,whereas the highest values of these characteristics for theβphase were found in the fusion zone(fZ).The change in the micro mechanical properties was accompanied by a change in the crystallographic texture components of the dominant a phase from(0001)and(11-20)components in the base material to(10-10)and(11-20)components in the *** introduction of tensile testing resulted in a continuous stress relaxation and improved the weld joint performances.

关键词： Ti-6Al-4 V Tungsten inert gas(TIG)weld Residual stress Local mechanical properties Crystallographic texture

Atomistic calculations of surface and interfacial energies of Mg_(17)Al_(12)-Mg system

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Journal of Magnesium and Alloys 2018年第4期6卷 375-383页

作者： f.X.Wang b.Li Department of Chemical and Materials Engineering University of NevadaRenoNV 89557USA Nevada Institute for Sustainability University of NevadaRenoNV 89557USA

It is well known that precipitation hardening in magnesium(Mg)alloys is far less effective than in aluminum ***,it is important to understand the surface and interfacial structure and energetics between precipitates and *** upscale modeling of magnesium alloys,these energy data are of great *** this work,we calculated the surface and interfacial energies of Mg_(17)Al_(12)-Mg system by carefully selecting the surface or interface termination,using atomistic *** results show that,the higher fraction of Mg atoms on the surface,the lower the surface energy of Mg_(17)Al_(12).The interfacial energy of Mg/Mg_(17)Al_(12)was calculated in which the burgers orientation relationship(OR)was *** was found that the(011)P|(0002)Mg interface has the lowest interfacial energy(248 mJ/m 2).because the burgers OR breaks when{10¯12}twin occurs,which reorients the matrix,the interfacial energy for Mg_(17)Al_(12)and a{10¯12}twin was also *** results show that after twinning,the lowest interfacial energy increases by 244 mJ/m^(2),and the interface becomes highly incoherent due to the change in orientation relationship between Mg_(17)Al_(12)and the matrix.

关键词： Mg_(17)Al_(12) Surface energy Interfacial energy Atomistic simulation

Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating b7H3

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Oncology research 2025年第1期33卷 103-121页

作者： Yan Lu Kang Wang Yuanhong Peng Meng Chen Lin Zhong Luji Huang f U Cheng Xindan Sheng Xin Yang Manzhao Ouyang George A Calin Zhiwei He China-America Cancer Research Institute Guangdong Medical University Dongguan 523808 China. GCP Center Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. Department of Gastrointestinal Surgery Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. The Second School of Clinical Medicine Southern Medical University Guangzhou 510080 China. Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer Center Houston TX 77030 USA. Department of Oncology Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China.

background:Immune checkpoint inhibitors play an important role in the treatment of solid tumors, but the currently used immune checkpoint inhibitors targeting programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), and cytotoxic T-lymphocyte antigen-4 (CTLA-4) show limited clinical efficacy in many breast cancers. b7H3 has been widely reported as an immunosuppressive molecule, but its immunological function in breast cancer patients remains unclear.Methods:We analyzed the expression of b7H3 in breast cancer samples using data from the Cancer Genome Atlas Program (TCGA) and the Gene Expression Omnibus (GEO) databases. MicroRNAs were selected using the Tarbase, miRTarbase, and miRbase databases. The regulatory role of the microRNA hsa-miR-214-3p on b7H3 was investigated through dual-luciferase reporter assays, which identified the specific action sites of interaction. The expression levels of b7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR (qPCR). experiments were performed to observe the effects of modulating the expression of b7H3 or hsa-miR-214-3p on breast cancer cell proliferation and apoptosis. Additionally, the regulatory impact of hsa-miR-214-3p on b7H3 was examined. Enzyme-linked immunosorbent assays (ELISA) and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells (PbMCs) on immune cells and associated cytokines.Results:In breast cancer tissues, the expression level of b7H3 is inversely correlated with that of hsa-miR-214-3p, as well as with the regulatory effects on breast cancercell behavior. Hsa-miR-214-3p was found to inhibit breast cancer cell growth by downregulating b7H3. Importantly, our research identified, for the first time, two binding sites for hsa-miR-214-3p on the 3' UTR of b7H3, both of which exert similar effects independently. Co-culture experime

关键词： b7H3 breast cancer Hsa-miR-214-3p Immunotherapy

Strategies for fermentable Sugar Production by Using Pressurized Acid Hydrolysis for Rice Husks

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Rice science 2019年第5期26卷 319-330页

作者： Giovanni b.PEDROSO Michael R.PHILIPPSEN Loisleini f.SALDANHA Raiara b.ARAUJO Ayrton f.MARTINS Chemistry Department Federal University of Santa Maria

This study investigated the use of leftover biomass(rice husks)as the raw material for the biotechnological production of platform chemicals and *** the biorefinery concept,different acid hydrolysates were studied and resulted into a wide range of treatment *** were applied throughout the procedures in multivariate experimental *** using the best hydrolytic conditions of 6.0%H3PO4,135oC(45 MPa)and reaction time of 62 min,21.0 g/L sugar hydrolysates were produced;by using the best hydrolytic condition of 4.5%HNO3,135oC/35 min,16.1 g/L sugar hydrolysates were produced;and with the hydrolysates use of 1.5%H2SO4 and 1.5%HCl,135oC/62 min,18.2 and 17.8 g/L sugar hydrolysates were produced,*** highest productivity,in terms of fermentable sugars,reached 68%of integral cellulose/hemicellulose fraction and surpassed those found in the literature,with regard to the processing of rice husks,by considering just one step *** hydrolysate,detoxified with active carbon,was used to prove this proposal viability,resulting in a fermentation substrate for ***(ATCC10020)and ***(LMG196)strains(natural producers of bioproducts),which certified the feasibility of the *** production of fermentable sugars from leftover biomass should encourage a search for new bioconversion routes,which can result in economic and environmental benefits and a spread of knowledge.

关键词： biorefinery multivariate design pressurized acid hydrolysis rice husk sugar