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In the mechanical, automobile, aerospace, and construction industries, Ti and steel are the mostly commercial materials be used. But the poor hardness, wear, and corrosion resistance limit their applications. In this study, we presented a composite material that consists of thermal-sprayed titanium (Ti) layer on AISI 1020 steel. Then we added different concentrations of c-BN to the electrolyte in the MAO process to enhance the wear resistance and corrosion resistance. The operating parameters of MAO were set to 35A/dm2 current density, 450V voltage and 10 minutes operating time. The concentration of c-BN added to the electrolytes were 0.1 g L-1, 0.3 g L-1, 0.5 g L-1, 0.7 g L-1, 0.9 g L-1, and denoted as Ti/MAO-BN1, Ti/MAO-BN3, Ti/MAO-BN5, Ti/MAO-BN7, Ti/MAO-BN9, respectively. To determine the properties of the composite coating, measurements of coating thickness, surface roughness, microstructure, hardness, XRD analysis, EDS observations were performed. Then potentiodynamic polarization test and a ball-on-disc wear test were used to determine the corrosion resistance and wear resistance. All the results indicated that all Ti/MAO contained c-BN (Ti/MAO-BN) have higher hardness, lower surface roughness, and thicker coatings thickness than that of Ti/MAO-free (Ti/MAO-F). In the corrosion resistance, Ti/MAO-BN was at least about 64% better than Ti/MAO-F, with Ti/MAO-BN9 being about 5 times better. In the wear resistance, Ti/MAO-BN reduces the wear volume at least about 59% compared to Ti/MAO-F, with Ti/MAO-BN9 reducing the wear volume by about 70%. [ABSTRACT FROM AUTHOR]

Stem cell transplantation is nearly available for clinical application in the treatment of ischaemic heart disease (IHD), where it may be joined traditional methods (intervention and surgery). The angiogenic ability of seed cells is essential for this applicability. The aim of this study was to reveal the presence of CD34+ angiogenic stem cells in human decidua at the first trimester and to use their strong angiogenic capacity in the treatment of IHD. In vitro, human decidual CD34+ (dCD34+) cells from the first trimester have strong proliferation and clonality abilities. After ruling out the possibility that they were vascular endothelial cells and mesenchymal stem cells (MSCs), dCD34+ cells were found to be able to form tube structures after differentiation. Their angiogenic capacity was obviously superior to that of bone marrow mesenchymal stem cells (BMSCs). At the same time, these cells had immunogenicity similar to that of BMSCs. Following induction of myocardial infarction (MI) in adult rats, infarct size decreased and cardiac function was significantly enhanced after dCD34+ cell transplantation. The survival rate of cells increased, and more neovasculature was found following dCD34+ cell transplantation. Therefore, this study confirms the existence of CD34+ stem cells with strong angiogenic ability in human decidua from the first trimester, which can provide a new option for cell‐based therapies for ischaemic diseases, especially IHD. [ABSTRACT FROM AUTHOR]