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Introduction. The increase in the number of respiratory lesions in the context of the COVID-19 pandemic and the tuberculosis epidemic leads to many complications, including calcification or pathological lung biomineralization (PBL). Respiratory remodeling caused by fibrosis and concomitant calcification is an important pathogen in chronic obstructive pulmonary disease (COPD) and subsequent chronic respiratory failure. The work aims to conduct bibliometric analysis and generalization of data from scientific sources to study the role of pathological biomineralization of lung tissue. Materials and methods. The authors searched for information in electronic databases such as PubMed, Scopus, Web of Science, and Google Scholar, in the key terms «pathological lung biomineralization» «lung calcification.» For bibliometric analysis, an online platform for monitoring and analysis of international research using visualization tools and modern citation metrics SciVal (Scopus) and a tool for building and visualizing bibliometric networks VOSviewer were used. Results. Pathological mineralization of the lungs is a multifactorial phenomenon: hypercalcemia, change of acid-base state in the alkaline direction, damage to lung tissue by infectious agents, genetic heredity. The danger of pathological biomineralization of the lungs is the gradual invisible occurrence of respiratory failure. We conducted a bibliometric analysis of the scientific literature. The number of publications on PBL has increased significantly over the past 10 years. Scientists from the United States, Japan, China, and India occupy the leading positions in this area. Analysis of publishing activity using the VOSviewer bibliometric network visualization tool for 1946-2022 by keywords showed the presence of 4 chronological publication stages. Among the 1356 publications analyzed, the most relevant areas of publishing activity are works on PBL in malignant neoplasms and tuberculosis, current radiological diagnosis of PBL, an association of PBL with inflammation and osteoporosis, biomarkers and biomaterials associated with PBL

The work is aimed at the development of a new sintered aluminium alloy with a low temperature coefficient of linear expansion that opens fundamentally new opportunities for solving the modern needs of domestic machinebuilding and instrument-making enterprises in light materials with special physical properties. Phase composition, structure and properties of cast aluminium alloys Al-Si-Ni with different contents of silicon and nickel, as well as powders obtained by grinding rapidly-quenched metal ribbons of these alloys in a high-energy ball mill are studied using various methods of structural analysis. The obtained values of the coefficient of linear expansion of the studied alloys in the cast state are significantly lower than those of pure aluminium, and they amount to = (11-15) 10-6 K-1. The method of obtaining a powder of a rapidly-crystallized alloy by manufacturing a rapidly-quenched metal ribbons using melt spinning followed by its dispersion in a high-energy ball mill is proposed for the fabrication of finely-dispersed powder and subse- quent hot pressing. [ABSTRACT FROM AUTHOR]

The Zn2TiO4 ceramics doped with manganese of nominal content from 0.0016 to 1.6 mol% were produced by a solid-state reaction and investigated by the X-ray diffraction, photoluminescence (PL), diffuse reflectance spectroscopy and electron paramagnetic resonance (EPR) methods. The influence of sintering conditions (annealing temperature in the range of 800–1200 °C and atmosphere, Mn concentration) on Mn charge state and red PL has been studied. All samples contained a spinel Zn2TiO4 crystal phase with a minor amount of ZnO. The ceramics showed a PL band peaked at 680 nm, which was ascribed to 2Eg → 4A2g transition of Mn4+Ti in the Zn2TiO4. The PL intensity increased with annealing temperature and Mn concentration. The highest PL intensity was found in the samples with 0.1 mol% Mn sintered at 1100 °C. In the EPR spectra, the signals ascribed to residual Cr3+ in the Zn2TiO4, Mn2+ in the ZnO (g = 2.0014, A = 74.1 × 10−4 cm−1, b20 = 235 × 10−4 сm−1) and Mn2+ in the Zn2TiO4 (g = 1.987, A = 74.510 × 10−4 сm−1, b20 = 45 × 10−4 сm−1) were detected. The intensity of EPR signal due to Mn2+ in the Zn2TiO4 increased noticeably in the samples with 1.0 mol% Mn and in those sintered at 1200 °C. This was accompanied by the decrease of Mn4+ PL intensity. It is concluded that manganese dopes the Zn2TiO4 as both Mn4+ and Mn2+, the Mn2+ incorporation is strongly promoted by high annealing temperature (> 1100 °C) and high Mn concentration (~ 1 mol%). It is proposed that optical absorption of Mn-doped Zn2TiO ceramics in the visible spectral range is determined by spin allowed transition of Mn4+Ti and Mn2+/3+ donor-type photoionization transition in the Zn2TiO4. [ABSTRACT FROM AUTHOR]

Amplification of a dosimetric EPR signal in mineralized biological materials available in limited quantities has been demonstrated in this paper. Powders of irradiated enamel, dentin, and bone tissue were placed into silica ampoules with the outer diameter close to 1.4 mm. To amplify the signal, the dielectric insert in the form of cylinder with the outer radius 2.85 mm, the inner radius 0.75 mm, and the height 1.85 mm made of a high-κ and low-loss ceramic material BaTi4O9 + 8.5% ZnO has been used. It has been shown that maximum signal amplification (about an order of magnitude) has been achieved when the sample is completely inserted into this dielectric. It has been found that the line shape of the dosimetric signal is not distorted, if using the dielectric insert. Decomposition of the amplified EPR spectra allowed us to determine the relative contribution of two types of CO2- radicals to the dosimetric signal, which coincides with the literature data. [ABSTRACT FROM AUTHOR]

The propagation of a dissipative soliton was experimentally studied in a two-dimensional binary complex plasma. The crystallization was suppressed in the center of the particle suspension where two types of particles were mixed. The motions of individual particles were recorded using video microscopy, and the macroscopic properties of the solitons were measured in the amorphous binary mixture in the center and in the plasma crystal in the periphery. Although the overall shape and parameters of solitons propagating in amorphous and crystalline regions were quite similar, their velocity structures at small scales as well as the velocity distributions were profoundly distinct. Moreover, the local structure rearranged drastically in and behind the soliton, which was not observed in the plasma crystal. Langevin dynamics simulations were performed, and the results agreed with the experimental observations.