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1.
Artif Cells Nanomed Biotechnol ; 52(1): 156-174, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38423139

RESUMEN

Osteoarthritis (OA) is a degenerative disease closely associated with Anoikis. The objective of this work was to discover novel transcriptome-based anoikis-related biomarkers and pathways for OA progression.The microarray datasets GSE114007 and GSE89408 were downloaded using the Gene Expression Omnibus (GEO) database. A collection of genes linked to anoikis has been collected from the GeneCards database. The intersection genes of the differential anoikis-related genes (DEARGs) were identified using a Venn diagram. Infiltration analyses were used to identify and study the differentially expressed genes (DEGs). Anoikis clustering was used to identify the DEGs. By using gene clustering, two OA subgroups were formed using the DEGs. GSE152805 was used to analyse OA cartilage on a single cell level. 10 DEARGs were identified by lasso analysis, and two Anoikis subtypes were constructed. MEgreen module was found in disease WGCNA analysis, and MEturquoise module was most significant in gene clusters WGCNA. The XGB, SVM, RF, and GLM models identified five hub genes (CDH2, SHCBP1, SCG2, C10orf10, P FKFB3), and the diagnostic model built using these five genes performed well in the training and validation cohorts. analysing single-cell RNA sequencing data from GSE152805, including 25,852 cells of 6 OA cartilage.


Asunto(s)
Anoicis , Osteoartritis , Humanos , Anoicis/genética , Aprendizaje Automático , Cadherinas , Osteoartritis/diagnóstico , Osteoartritis/genética , Análisis de Secuencia de ARN , Proteínas Adaptadoras de la Señalización Shc
2.
Materials (Basel) ; 16(13)2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37445096

RESUMEN

To improve the heat resistance of titanium alloys, the effects of Y content on the precipitation behavior, oxidation resistance and high-temperature mechanical properties of as-cast Ti-5Al-2.75Sn-3Zr-1.5Mo-0.45Si-1W-2Nb-xY (x = 0.1, 0.2, 0.4) alloys were systematically investigated. The microstructures, phase evolution and oxidation scales were characterized by XRD, Laser Raman, XPS, SEM and TEM. The properties were studied by cyclic oxidation as well as room- and high-temperature tensile testing. The results show that the microstructures of the alloys are of the widmanstätten structure with typical basket weave features, and the prior ß grain size and α lamellar spacing are refined with the increase of Y content. The precipitates in the alloys mainly include Y2O3 and (TiZr)6Si3 silicide phases. The Y2O3 phase has specific orientation relationships with the α-Ti phase: (002)Y2O3 // (1¯1¯20)α-Ti, [110]Y2O3 // [4¯401]α-Ti. (TiZr)6Si3 has an orientation relationship with the ß-Ti phase: (022¯1¯)(TiZr)6Si3 // (011)ß-Ti, [1¯21¯6](TiZr)6Si3 // [044¯]ß-Ti. The 0.1 wt.% Y composition alloy has the best high-temperature oxidation resistance at different temperatures. The oxidation behaviors of the alloys follow the linear-parabolic law, and the oxidation products of the alloys are composed of rutile-TiO2, anatase-TiO2, Y2O3 and Al2O3. The room-temperature and 700 °C UTS of the alloys decreases first and then increases with the increase of Y content; the 0.1 wt.% Y composition alloy has the best room-temperature mechanical properties with a UTS of 1012 MPa and elongation of 1.0%. The 700 °C UTS and elongation of the alloy with 0.1 wt.% Y is 694 MPa and 9.8%, showing an optimal comprehensive performance. The UTS and elongation of the alloys at 750 °C increase first and then decrease with the increase of Y content. The optimal UTS and elongation of the alloy is 556 MPa and 10.1% obtained in 0.2 wt.% Y composition alloy. The cleavage and dimples fractures are the primary fracture mode for the room- and high-temperature tensile fracture, respectively.

3.
Materials (Basel) ; 15(19)2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36234254

RESUMEN

X2CrNi12 ferritic stainless steel has a wide range of application prospects in the railway transportation, construction, and automobile fields due to its excellent properties. The properties of X2CrNi12 ferritic stainless steel can be further improved by cold-rolling and subsequent annealing treatment. The purpose of this work is to investigate the effect of cold-rolling reduction on the microstructure, texture and corrosion properties of the recrystallized X2CrNi12 ferritic stainless steel by using SEM, TEM, EBSD and electrochemical testing technology. The results show that the crystal orientation characteristics of the cold-rolled sheet could be inherited into the annealed sheet. The higher cold-rolling reduction could promote the deformed grains rotating into the {111} orientation, increasing storage energy and driving force for recrystallization, which could reduce the recrystallized grain size. The orientation densities of α-fiber and γ-fiber were low at 50% cold-rolling reduction. After recrystallization annealing, a large number of grains with random orientation could be produced, and the texture strength was weakened. When the cold-rolling reduction rose to 90%, the γ-fiber texture at {111}<110> was strengthened and the α-fibers, particularly the {112}<110> component, were weakened after recrystallisation annealing, which could improve the formability of the steels. The proportions of special boundaries, i.e., low-angle grain boundaries and low-Σ CSL boundaries, among the grain boundary distribution of the recrystallized X2CrNi12 stainless steel were higher when the reduction was 90%, especially when the annealing temperature was 770 °C. Additionally, the proportion of LAGBs and low-Σ CSL boundaries were 53% and 7.43%, respectively, which improves the corrosion resistance of the matrix, showing the best corrosion resistance.

4.
Materials (Basel) ; 15(5)2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35268932

RESUMEN

Ti-Cu alloys have broad application prospects in the biomedical field due to their excellent properties. The properties of Ti-Cu alloys are strongly dependent on Cu content, microstructures, its Ti2Cu phase and its preparation process. The aim of this work is to investigate the effect of Cu content on the precipitation behaviors, mechanical and corrosion properties of the as-cast Ti-Cu alloys. The microstructures and phase evolution were characterized by SEM and TEM, and the properties were studied by tensile and electrochemical test. The results show that the volume fraction of Ti2Cu phase increases with the increase of Cu content. The Ti2Cu phase presents a variety of microscopic morphologies with different Cu content, such as rod, granular, lath and block shaped. The crystal orientation relationships between the Ti2Cu and α-Ti matrix in Ti-4Cu and Ti-10Cu alloys are (103)Ti2Cu//(0[11¯11)α-Ti, [3¯01]Ti2Cu//[21¯1¯0]α-Ti, and (103)Ti2Cu//(0002)α-Ti, [3¯31]Ti2Cu//[12¯10]α-Ti, respectively. The tensile strength, Vickers hardness and Young's modulus of the Ti-Cu alloys increase with the increase of Cu content, whereas the elongation decreases. The fracture morphologies of these alloys reveal ductile, ductile-brittle hybrid, and cleavage brittle mode, respectively. The corrosion resistance of the Ti-Cu alloys in SBF solution can be described as: Ti-4Cu alloy > Ti-10Cu alloy > Ti-7Cu alloy. The volume fraction of Ti2Cu phases and the "protective barrier" provided by the fine lath Ti2Cu phases strongly affected the electrochemical performances of the alloys.

5.
Materials (Basel) ; 15(6)2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35329515

RESUMEN

In order to explore the influence of space ultraviolet radiation on spacecraft lubricating materials, an in-situ friction experimental device simulating space ultraviolet radiation was developed in the laboratory, and the experimental verification was carried out. This paper firstly introduced the design index, structure and working principle of the space ultraviolet irradiation simulation device, and then calibrated and tested the parameters of the whole device, and also conducted a virtual operation of the device's operation effect by simulation software, and the results showed that it met the design index. Finally, the validation tested of the ultraviolet irradiated in-situ friction experimental device were described in detail. By using the device to irradiate the samples, it was found that the in-situ ultraviolet irradiation device could achieve the expected irradiation effect, and the irradiation would lead to changes in the surface structure and properties of the PTFE material, while also achieving the need for in-situ spatial friction property testing of the material, providing favorable conditions for future testing.

6.
Materials (Basel) ; 15(5)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35269082

RESUMEN

To investigate atomic oxygen effects on tribological properties of Mo/MoS2-Pb-PbS film and further enlarge application range, atomic oxygen exposure tests were carried out for 5 h, 10 h, 15 h, and 20 h by the atomic oxygen simulator with atomic oxygen flux of 2.5 × 1015 atoms/cm2·s. The exposure time in test was equivalent to the atomic oxygen cumulative flux for 159.25 h, 318.5 h, 477.75 h, and 637 h at the height of 400 km in space. Then, the vacuum friction test of Mo/MoS2-Pb-PbS thin film was performed under the 6 N load and 100 r/min. By SEM, TEM, and XPS analysis of the surface of the film after atomic oxygen erosion, it was observed that atomic oxygen could cause serious oxidation on the surface of Mo/MoS2-Pb-PbS film, and the contents of MoS2, PbS, and Pb, which were lubricating components, were significantly reduced, and oxides were generated. From AES analysis and the variation in the main element content, Mo/MoS2-Pb-PbS thin film showed self-protection ability in an atomic oxygen environment. Hard oxide generated after atomic oxygen erosion such as MoO3 and Pb3O4 could cause the friction coefficient slight fluctuations, but the average friction coefficient was in a stable state.

7.
Sensors (Basel) ; 21(3)2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33525525

RESUMEN

The generation and propagation of cracks are critical factors that affect the performance and life of large structures. Therefore, in order to minimize maintenance costs and ensure personal safety, it is necessary to monitor key structures. The sensor based on ultra-high frequency radio frequency identification (UHF RFID) antenna has the advantages of passive wireless, low cost, and great potential in the field of metallic structure health monitoring. In this paper, aimed at the key parts of a metallic structure, a dual-tag system is used for crack monitoring. In conjunction with mode analysis, the principles of the sensing tag and the coupling principles of the dual-tag are analyzed. Considering that the dual-tag is placed in different methods, the effect of mutual coupling on the sensing performance of the tag is studied. The results show that the frequency of the sensing tag can be tuned by adding the interference tag, and the dual-tag sensor system has reasonable sensitivity. The results also provide potential guidance for the optimal placement of multiple tags in the near-field region.

8.
Materials (Basel) ; 13(5)2020 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-32121346

RESUMEN

The cyclic oxidation behaviors of the as-cast Ti-1100-xNb (x = 0.5, 1.0, 1.5, 2.0) alloys exposed at 650 °C for up to 100 h were systematically investigated. The aim of this work is to explore the in-depth oxidation mechanism by using the oxidation kinetics and the structure of the oxide products. The oxidation kinetics were determined by thermogravimetrically, and the microstructure and composition of the oxidation scale were studied by using XRD and SEM. The results demonstrate that Nb can significantly improve the oxidation resistance. However, the average weight gains of the alloys decrease firstly and then increase with the increase of Nb content. The oxidation kinetics obeys a parabolic model. The Ti-1100-1.0Nb alloy has the lowest kp value, which is 5.7 10-13 g2cm-4s-1. The surface oxidation products are mainly composed of massive or acicular rutile-TiO2, TixO (x = 3, 6), NbO2 and Al2O3. Besides, Al2(MoO4)3 oxide is also presented on the oxidation surface of the Ti-1100-1.5Nb alloys. Ti-1100-1.0Nb alloy shows the best oxidation resistance property revealed by combining weight gains and EDS-SEM element content profiles analysis. The interaction of Nb, O, Ti, and other elements retarded the diffusion of O atoms into the alloys, which improves the oxidation resistance.

9.
Materials (Basel) ; 12(20)2019 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-31635405

RESUMEN

Conventional carburizing has disadvantages, such as high energy consumption, large deformation of parts, and an imperfect structure of the carburizing layer. Hence, a rare earth ion pre-implantation method was used to catalyze and strengthen the carburized layer of 20Cr2Ni4A alloy steel. In this study, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive microanalysis (EDS), transmission electron microscopy (TEM), and Rockwell/Vickers hardness testing were used to analyze the microstructure, phase composition, retained austenite content, hardness, carburized layer thickness, and carbon diffusion. The results showed that lanthanum and yttrium ions implanted into the 20Cr2Ni4A steel formed solid solutions of rare earth ions and a large number of dislocations, which improved the diffusion coefficient of carbon elements on the carburized surface and the uniformity of the carbon distribution. Simultaneously, rare earth ion implantation improved the structure and hardness of the vacuum carburized layer. Compared to the lanthanum ion implantation, yttrium ion implantation caused the structure of the carburized layer to be finer, and the carbon diffusion coefficient increased by 1.17 times; in addition, the surface hardness of the carburized layer was 61.8 HRC.

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