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61.
Alexander Balatskiy Ilia Ozhimalov Maria Balatskaya Alexandra Savina Julia Filatova Natalia Kalinina Vladimir Popov Vsevolod Tkachuk 《International journal of molecular sciences》2022,23(3)
The local development of atherosclerotic lesions may, at least partly, be associated with the specific cellular composition of atherosclerosis-prone regions. Previously, it was demonstrated that a small population of immature vascular smooth muscle cells (VSMCs) expressing both CD146 and neuron-glial antigen 2 is postnatally sustained in atherosclerosis-prone sites. We supposed that these cells may be involved in atherogenesis and can continuously respond to angiotensin II, which is an atherogenic factor. Using immunohistochemistry, flow cytometry, wound migration assay xCELLigence system, and calcium imaging, we studied the functional activities of immature VSMCs in vitro and in vivo. According to our data, these cells do not express nestin, CD105, and the leptin receptor. They are localized in atherosclerosis-prone regions, and their number increases with age, from 5.7% to 23%. Immature VSMCs do not migrate to low shear stress areas and atherosclerotic lesions. They also do not have any unique response to angiotensin II. Thus, despite the localization of immature VSMCs and the presence of the link between their number and age, our study did not support the hypothesis that immature VSMCs are directly involved in the formation of atherosclerotic lesions. Additional lineage tracing studies can clarify the fate of these cells during atherogenesis. 相似文献
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Kiselev A. I. Akashev L. A. Popov N. A. 《Protection of Metals and Physical Chemistry of Surfaces》2022,58(2):308-317
Protection of Metals and Physical Chemistry of Surfaces - Optical constants n and k of polycrystalline films of aluminum and Al–4.45 at % La alloy have been measured at room temperature. The... 相似文献
64.
I.E. Tyschenko M. Voelskow A.G. Cherkov V.P. Popov 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(8-9):1277-1280
Nanometer-thick silicon-germanium-on-insulator (SGOI) structures have been produced by the implantation of Ge+ ions into thermally grown SiO2 layer and subsequent hydrogen transfer of silicon film on the Ge+ ion implanted substrate. The intermediate nanometer-thick Ge layer has been formed as a result of the germanium atom segregation at the Si/SiO2 bonding interface during annealing at temperatures 800–1100 оС. From a thermodynamic analysis of Si/Ge/SiO2 system, it has been suggested that the growth of the epitaxial Ge layer is provided by the formation of a molten layer at the Si/SiO2 interface due to the Ge accumulation. The effect of germanium on the hole mobility in modulation-doped heterostructures grown over the 3–20 nm thick SGOI layers was studied. An increase in the Hall hole mobility in SGOI-based structures by a factor of 3–5 was obtained in comparison with that in respective Ge-free SOI structures. 相似文献
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Pablo Salcedo-Abraira Sergio M.F.Vilela Artem A.Babaryk Maria Cabrero-Antonino Pedro Gregorio Fabrice Salles Sergio Navalon Hermenegildo Garcia Patricia Horcajada 《Nano Research》2021,14(2):450-457
A novel microporous two-dimensional(2D)Ni-based phosphonate metal-organic framework(MOF;denoted as IEF-13)has been successfully synthesized by a simple and green hydrothermal method and fully characterized using a combination of experimental and computational techniques.Structure resolution by single-crystal X-ray diffraction reveals that IEF-13 crystallizes in the triclinic space group Pi having bi-octahedra nickel nodes and a photo/electroactive tritopic phosphonate ligand.Remarkably,this material exhibits coordinatively unsaturated nickel(II)sites,free-P03H2and-P03H acidic groups,a C02accessible microporosity,and an exceptional thermal and chemical stability.Further,its in-deep optoelectronic characterization evidences a photoresponse suitable for photocatalysis.In this sense,the photocatalytic activity for challenging H2generation and overall water splitting in absence of any co-catalyst using UV-Vis irradiation and simulated sunlight has been evaluated,constituting the first report for a phosphonate-MOF photocatalyst.IEF-13 is able to produce up to 2,200 fimol of H2per gram using methanol as sacrificial agent,exhibiting stability,maintaining its crystal structure and allowing its recycling.Even more,170μmol of H2per gram were produced using IEF-13 as photocatalyst in the absence of any co-catalyst for the overall water splitting,being this reaction limited by the 02reduction.The present work opens new avenues for further optimization of the photocatalytic activity in this type of multifunctional materials. 相似文献
67.
An electrolytic method for preparing chemically resistant Am–Ni alloys was studied. Optimum electrolysis conditions ensuring the maximal (up to 95%) recovery of Am from the electrolyte with the alloy formation were found. The compositions of the alloys formed in the process were determined. 相似文献
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