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The phase equilibria in the Al2O3–SiO2–ZrO2 system up to a temperature of 2550.15 K, calculated using the Nuclea database, are considered in comparison with the experimental data available in the literature. The calculated eight isothermal sections of the phase diagram of the system under consideration are an addition to the previously obtained few experimental data. The phase equilibria in the Al2O3–SiO2–ZrO2 system are discussed in comparison with the corresponding binary systems.

In the study, the partial sequences of several nitrate transporter/channel genes of the NPF, NRT2, NAR2 and SLAC/SLAH families from the halophyte Suaeda altissima (L.) Pall. were identified, and their relative transcript abundance in S. altissima plants grown in nutrient media with different concentrations of $${\text{NO}}_{3}^{ - }$$ and Cl– was examined by qRT-PCR. Identification of the partial S. altissima nitrate transporter sequences were carried out assuming similarity of putative S. altissima genes with homologous genes from the halophytes S. fruticosa and S. glauca, which are closely related to S. altissima. Nucleotide sequences of S. fruticosa and S. glauca homologous genes were obtained by in silico analysis of the de novo assembled transcriptomes of these halophytes. The short-read RNA arrays for the transcriptome assemblies were taken from the BioProject database ( https://www.ncbi.nlm.nih.gov/bioproject/ ), NCBI, Acc. no. #PRJNA279962 and #PRJNA295637. Based on the identified contigs in the assembled S. fruticosa and S. glauca transcriptomes that were characterised as putative nitrate transporters or channels, primer sets were designed for the amplification of sequences encoding S. altissima nitrate transporters: SaNPF6.3 (MK 580125.1), SaNRT2.1 (MK 580128.1), SaNRT2.5 (MK 580129.1), SaNAR2.1 (MK 580130.1), SaSLAH1.1 (MK 580131.1) and SaSLAH1.2 (MK 580132.1) (GenBank Acc. no. are given, https://www.ncbi.nlm.nih.gov/genbank/ ). It was shown that the expression of S. altissima genes under consideration is organ-specific and changed in response to changes in NO3ˉ and NaCl concentrations in the growth medium.

New data are reported on the age, composition, and formation conditions of the Late Triassic granitoids of minor intrusions from the eastern part of the Bureya continental massif of the Central Asian fold belt, and their geodynamic interpretation is given. U–Pb geochronological zircon studies indicate that the rocks of the Altakhta syenite–leucogranite complex were formed in two phases within 235–224 Ma. The first phase (235.3 ± 2.9–230 Ma) was responsible for the formation of magmatic rocks that are similar to the А1-type intraplate granitoids in terms of geochemistry and resemble subduction- and collision- related granitoids in terms of REE composition. The second phase (226–224 Ma) produced granites similar to А2-type and А2 + I and S-types. A combination of within-plate and subduction signatures and the presence of A, I, and S-type rocks of similar ages in this complex supports their formation in a transform continental margin setting.

We studied the regularities of distribution of siderophile elements, including platinum group elements (PGE), in rock and in sulfides from Archean (2814 ± 51 Ma) peridotites collected in a fragment of deformed dike within the Bug granulite complex, Ukrainian Shield. In comparison with the primitive mantle, the studied rocks are enriched in Rh, Pd, Ni, Fe, and Co, and are characterized by low concentrations of other PGE. Sulfides are represented by a high-temperature variety of pentlandite and a small amount of chalcopyrite, with an inhomogeneous PGE distribution in them. Pd/Ir ratio typical of superchondrite is revealed for rocks and some sulfides. It is supposed that enrichment in Pd was not resulted from fractionation, but was rather related to mantle metasomatism. Saturation of the melt with sulfides and liquation process were favored by contamination of harzburgite with the host gneissic enderbite and fractionation of olivine. Solid sulfide solutions formed from sulfide melts at temperatures close to the crystallization temperature of magnesium phlogopite from a silicate melt.

The ecological situation on Shkot Island and the adjacent part of Russky Island in terms of mercury content in soils and leaves of tree and shrubbery vegetation has been analyzed. The main sources of mercury input into geosystems have been revealed. To determine its content in soils and vegetation, 3 and 16 plots have been sampled on Russky and Shkot islands, respectively. It is shown that the soil cover of Russky and Shkot islands is represented by typical and dark brown burozems (brown forest soils) and their pyrogenic analogues. Mercury distribution depends on soil properties in a soil cover and on plant species in vegetation. The results of laboratory research of mercury content in geosystems are presented. Using interpolation method, maps of mercury content in the soil cover and oak leaves (Quercus mongolica) have been compiled for Shkot Island. The average mercury content in the soil cover of Shkot Island and the adjacent part of Russky Island is 81.2 ng/g. The average contents in various plant species are as follows: 26.3 ng/g for Carpinus cordata, 24.5 ng/g for Quercus mongolica, 9.1 ng/g for Artemisia gmelinii. Such variations are caused by different mercury accumulation ability of the plant species. It is assumed that the high mercury content in the soil and vegetation in the eastern part of Shkot Island is due to tectonic features. The maximum soil mercury content on Shkot Island is confined to the Dotovaya Bay coast, which is the island’s main recreation area in summer. Numerous campfires and wood and household waste (first of all, polyethylene) combustion lead to mercury redistribution in the adjoining territories. In terms of mercury content, the ecological setting in the soil-vegetation cover of Russky and Shkot islands is viewed as favorable. The mercury content in soil is much below maximum permissible concentration. Since maximum permissible concentration of mercury in plants is not available, the comparison has been carried out for Clarke values. The mercury content exceeds Clarke values for Carpinus cordata and Quercus mongolica, which can be attributed to natural regional specifics. The obtained data can be used as background indicators.

The ground control using optical fibers is discussed. The designed monomode fiber pressure sensor is capable to perform high-precision measurement of overlying rock mass pressure imposed on walls of underground excavation. The mathematical apparatus is presented for the calculation of radiation intensity of optical wave traveling along an optical fiber with and with no mechanical effects. The simulation model is developed for an underground excavation with steel arch support. The model is equipped with the fiber-optic monitoring system and pressure sensors. This model enables practicing the ground control methods and measurements. The critical element of the simulation model is its hardware/software complex with interface showing four check zones with fiber-optic pressure sensors. This monitoring system is explosion-proof and is suitable for operation in super hazardous mines in terms of gas and dust outbursts.

In this paper, the game-theoretic model with production and knowledge externalities on a network with two time periods formulated by Matveenko and Korolev is further developed. This model is an extension of the Romer two-period model. The simplest complete network with heterogeneous agents—the dyad with agents differing by their productivity—is considered. Dynamics in the dyad are studied. All possible game equilibria in the dyad and the conditions of their existence are found. Conditions for the dynamic stability of equilibria are established.

In a time interval of 10 μs, a system containing 128 molecules of dilinoleoyl phosphatidylcholine and water molecules as a solvent is modeled by the molecular dynamics method using the coarse-grained approach. The structure of the phospholipid bilayer, stable for 10 μs, is obtained.

Powders of Bi4V2O11 and Bi4V1.8Me0.2O11–d (Me = Co, Cu, Fe, Mn, or Nb) are synthesized according to standard ceramic techniques and are characterized via X-ray diffraction. The average particle size is 9–12 µm, and the specific surface area is 1.2–1.6 m2/g. The photocatalytic activity of all samples is studied using the example of rhodamine B oxidation in an aqueous solution. Its value is found to be quite high and depends directly on the ionic radii of the metals contained in layers of (V(ME)O3◻0.5)2− layers, where ◻ is an oxygen vacancy. A mechanism is proposed for the action of Bi4V2O11-based photocatalyst (BIMEVOX), and the formation of $${\text{O}}_{2}^{{ \bullet - }}$$ and $${}^{ \bullet }{\text{OH}}$$ radicals as the main oxidizing agents of rhodamine B is proven.

Data obtained on carbonates and metaterrigenous rocks of the Devonian complex of the Sultan-Uizdag Range, northwestern Uzbekistan, which are carbonized in local deformation zones, are used in a generalized interpretation of the genesis of carbonaceous matter by means of decomposition of carbonates under the effect of seismogenic movements. The release of free carbon is facilitated by synchronous Fe–Mg metasomatism and by the reducing conditions in the presence of hydrogen. Based on literature data on experimental modeling of carbonization processes at high-speed shear deformations of carbonates in a hydrogen medium, a possible scenario is considered for the generation of hydrogen on the surfaces of quartz dislocations in the presence of water in metaterrigenous rocks in association with carbonates. The variation of carbon isotope composition over the volume of the carbonate and terrigenous rocks is extremely heterogeneous, with the 13C isotope enriched in the fracture zones and 12C enriched in the near-fracture volumes of decompression-damaged rocks. It is hypothesized that deformations can affect the fractionation of stable carbon isotopes. With regard for literature data, it is demonstrated that isotope exchange can proceed between the free carbon and carbonate carbon. Various aspects are discussed of the influence of mineral-phase and structural–textural transformations of carbonate rocks at their thermomechanical decomposition under shearing on the geomechanical behavior of the fracture, manifestations of mechanical instability in it, and causes of frictional weakening.

The ultrastructure of the mesonephros of the natural population of Atlantic salmon smolts (Salmo salar L., 1758) and brown trout smolts (Salmo trutta L., 1758) inhabiting the Luga River in Leningrad oblast, Russia, was studied. The general plan of the mesonephric kidney structure is presented. Specific features of the structure of leukocytes and nephron of salmonids under smoltification are described. The size of leukocytes and the height of the epithelial cells of the proximal tubules of the kidneys of salmon smolts are greater in comparison with those kidney cells of freshwater teleost fishes. The number, size, and population density of mitochondria, as well as the development of a rough and smooth endoplasmic reticulum in different types of cells of the mesonephros of salmon smolts, are higher than those in freshwater fish. A similar pattern is observed for the number of vesicles in the basal part of the distal tubule of the kidneys of the salmon smolt in comparison with freshwater fish. Cells with radially arranged vesicles (CRAVs) of different ultrastructures have been found for the first time in mesonephros of Atlantic salmon. All the described features of the ultrastructure of mesonephros cells are revealed for the smolts prior their migration into sea water.

Oncolytic Newcastle disease viruses (NDVs) make up a group of antitumor agents for the experimental treatment of oncological diseases that nonpathogenic for human beings. It is known that realization of the cytotoxic effect of NDV strains on the tumor cells depends on the peculiarities of viral genome structure, strain virulence, and tumor cell culture (National Institutes of Health, 2018). At the same time, the mechanism of NDV-induced death has been poorly studied. The aim of this work was to study the nature of morphological changes in HeLa and Hep-2 (HeLa derivative) human tumor cells after infection with the wild-type mesogenic NDV strain NDV/Altai/pigeon/770/2011. The calculation of living tumor cells using MTT test demonstrated that the cytotoxic activity of NDV/Altai/pigeon/770/2011 strain in 144 h after infection decreases the cell viability till 13.08 ± 8.29% (HeLa) and 4.74 ± 3.29% (Hep-2, HeLa derivative). A routine staining detected morphological traits of degradation of infected cells, while morphometric studies detected an increase in the value of the nuclear–cytoplasmic ratio (NCR). The presence of a virus in the tumor cells was visualized by the method of immunocytochemical staining (ICS) using antibodies to the HN glycoprotein of the NDV envelope. The results of immunodetection of tumor necrosis factor α (TNFα) suggest the activation of cell death along the apoptosis pathway against the background of viral infection. The results obtained indicate a pronounced cytotoxic activity of wild-type NDV/Altai/pigeon/770/2011 strain regarding HeLa and Hep-2 (HeLa derivative) adenocarcinoma cells and sensitivity of the studied cell lines to the oncolytic effect of NDV.

Petrogeochemical and geochronological studies were conducted on the main varieties of granitoids from the Sedelga and Berezovsky batholiths in the eastern Bureya continental Massif of the Central Asian Fold Belt. SHRIMP-II U–Pb zircon dating of granitoids constrained the time of formation to the Late Triassic and Early Jurassic between 208 to 193 Ma. Our studies revealed that the batholiths contain peraluminous granitoids of high K calc-alkaline series clearly enriched in Rb, K, Th, U, and Pb and relatively depleted in Nb, Ta, Y, HREE, Sr, Ba, Ti, and P and belong to I-type granites. Synthesis of the U–Pb geochronological data indicates that magmatism of tectonic blocks constituting the Bureya Massif at 213–183 Ma was accompanied by the emplacement of granitoid rocks of the Khara Complex. Strike-slip tectonics as a reflection of oblique collision of continental blocks and transform movement might have been an important mechanism of granitoid derivation in the Bureya Massif. Strike-slip faults were likely to penetrate deep into the crust initiating the ascent of an asthenospheric diapir and its fluids into the higher crustal levels thus transferring the heat and triggering melting with appreciable concentrations of Th, U, Rb, Pb and losses of Sr, P, Ba, and Ti. The depletion in Nb, Ta, Ti, and P and the enrichment in Pb make these granitoids similar to those of subduction zones. Granitoids of the Khara Complex display subduction-related (associated with the preceding subduction) and within-plate (associated with an asthenospheric diapir and its fluids) geochemical features, which is characteristic of transform margin environments. The most likely settings for granitoid magmatism to occur throughout the eastern margin of the Bureya Massif in the Late Triassic and Early Jurassic were transform settings associated with asthenospheric diapirism following the cessation of subduction.

The activity of polyvalent elements in the geochemical processes is to a considerable extent determined by the valence state. A change in the valence is dependent on many factors, but the redox conditions of the medium where magma is generated are considered the main factor. The ratio between divalent and trivalent iron in magmatic rocks is a reliable and an accessible indicator of the redox conditions that determine a whole set of mineralogical, geochemical and physical parameters including ferruginosity of dark-colored minerals, the ore mineral (magnetite–ilmenite) composition, the weight of the ore fraction, and magnetic susceptibility. Based on the above parameters, the zones are distinguished where magmatic rocks of the magnetite and ilmenite series are developed in the Sikhote Alin Orogenic Belt. All known tin and tungsten deposits and occurrences in the Sikhote Alin are confined to the ilmenite series (the axial zone of the belt). The ilmenite rock series are framed by the magmatic rocks of the magnetite series; the epithermal gold–silver and copper–porphyry deposits are associated with these rocks.

The relevance of this work is due to the importance of identifying latent defects in building structures of reinforced concrete foundations. The results of the study of defects and damage to reinforced concrete structures are provided. It is proposed to use a telecommunication optical fiber of the G.652 standard as a sensor for identifying mechanical influences for long-haul objects. The optical fiber is placed directly inside a reinforced concrete foundation. As a result, we revealed dependences of the increase in the amount of additional optical losses arising in the fiber located in the concrete beam under varying mechanical stresses and deformations with increasing load. Based on the data obtained, two schemes have been proposed that make it possible to locate local latent defects in the structures of reinforced concrete foundations. New results of measuring the values of mechanical damage and deformation of concrete beams in real time when varying the properties of light passing through an optical fiber of the G.652 standard are obtained.

This research analyses the structure and functions of bacterial communities of regressive spots in ombrotrophic bogs. Algal biomass was found to predominate in the biomass structure of regressive spots, while fungal mycelial biomass predominated in the layers of non-regressive ombrotrophic bog peat. A number of bacteria in regressive spots determined by direct counts was three to seven times higher than the one in non-regressive ombrotrophic bog peat. Although the Proteobacteria and Acidobacteria predominated in the samples studied, their shares in non-regressive ombrotrophic bog peat were lower. Members of the phylum Verrucomicrobia predominated in the regressive spots, while in non-regressive raised bog peat they were among the minor components. It was found that the epiphytic-saprotrophic bacterial communities were dominated by bacilli during the dry season and by the proteobacteria during the wet season. According to the results of the 16S rRNA gene sequencing, the bacteria found were identified as Chryseobacterium, Stenotrophomonas, Pseudomonas, and Chromobacterium. Physiological activity of the bacterial communities in regressive spots was similar to that of fen peat communities due to abundance of bacteria using easily accessible polymers. Nitrogen-fixing activity of the bacterial communities was found to be significantly higher in regressive spots than in non-regressive ombrotrophic bog peat.

The prototype of a nuclear-polarized hydrogen/deuterium molecular source based on the classical Stern–Gerlach design was tested at the Budker Institute of Nuclear Physics. Its major components are an annular nozzle cooled down to 6.5 K and two superconducting sextupole magnets. The measured flow of polarized hydrogen molecules was 3 × 1012 mol/s at a total gas flow through the nozzle of 4 ×10–2 Torr L/s. The results obtained will be used to construct a more intense source of polarized molecules.

Bacterial communities of the six Ericaceae bog plants were studied. The total number of bacteria on the vegetative organs of the Ericaceae plants was high and comparable to the one on Sphagnum mosses. Members of bacterial taxa colonizing both heather plants and Sphagnum mosses were identified. According to their 16S rRNA gene sequences, predominant bacteria of the epiphytic-saprotrophic complex were identified as Pseudomonas, Stenotrophomonas, Serratia, and Chryseobacterium species. The physiological diversity of the hydrolytic bacterial complex was significantly higher in the Ericaceae plants than in the Sphagnum mosses. Analysis of the taxonomic position and functions of identified bacteria indicated that the studied bacteria were capable of stimulating the growth of plants inhabiting ombotrophic bogs.

We simulate the motion of hydrogen and deuterium molecules in the magnetic system of a setup intended for obtaining nuclear-spin-polarized molecules. Spatial separation of molecules with different magnetic moment projections by the spin filtration method in a nonuniform magnetic field is performed using superconducting sextupole magnets. Calculations are carried out for a magnetic field induction of 3.7 T at the poles and a nozzle temperature of 7 K. Simulation show that the ratio of polarized flux of hydrogen molecules to the detector to the total flux from the source nozzle is 2.3 × 10–6, nuclear polarization being close to 100%. Calculations performed for deuterium reveal that this ratio is 7 times smaller due to the smallness of the magnetic moment relative to hydrogen molecules. Trajectories of molecules in the magnetic system and their spatial distribution are represented graphically. Mathematical aspects of the algorithm of the computer program developed for this purpose are considered.

Tick-borne encephalitis (TBE) is caused by a neurotropic RNA virus from the Flavivirus genus. TBE is characterized by a significant variability of clinical manifestations from nonparalytic forms (fever, meningitis) to severe paralytic (focal) forms (meningoencephalitis, poliomyelitis, polioencephalomyelitis). The result of interaction between a virus and a host (and, consequently, the viral disease course and outcome) largely depends on genetically determined ability of the host (particularly, human) organism immune system to suppress the development of viral infection. However, hereditary predisposition to TBE has been rather poorly studied in human populations. In this study, the results of whole exome sequencing of DNA samples from 22 Russian non-immunized TBE patients with severe TBE forms and 17 control individuals from the same populations are presented. Sixteen single nucleotide polymorphisms (SNPs) associated with predisposition to severe forms of TBE were identified. The genotype and allele frequencies for three of these SNPs localized in the ABCB9 (rs4148866, G/A, intron), COL22A1 (rs4909444, G/T, Ala938Asp), and ITGAL (rs1557672, G/A, intron) genes were then studied in larger samples of patients with different forms of TBE (n = 177) and in the control population (n = 215). As a result, the association of the ABCB9 and COL22A1 gene SNPs with the development of severe forms of TBE was for the first time demonstrated in the Russian population. The hypothesis regarding a possible mechanism of the effect of the ABCB9 gene intronic SNP on the process of human infection with TBE virus is considered.

The setup is designed to produce spin-polarized hydrogen and deuterium molecules. Superconducting sextupole magnets with a magnetic induction of 3.4 T near the poles and a field gradient of 320 T/m were used for the spatial separation of molecules with different magnetic moments by spin filtration in an inhomogeneous magnetic field. The choice of the location of the polarized-molecule source elements is justified. Cryogenic pumps are used in the molecular-beam detection chamber in order to obtain an ultrahigh vacuum. At a nozzle temperature of 7 K, the measured flux of spin-polarized hydrogen molecules is 3 × 1012 molecules/s. For deuterium, the measured flux is lower by more than seven times due to the small magnetic moments.

Data on the U–Pb (SIMS SHRIMP-II) age (3628 ± 38 and 2845 ± 65 Ma) of zircon from the inclusion of mafic granulite in gneiss–enderbites of the Bug complex in Ukraine are obtained. A zircon age of 3628 ± 38 Ma for the first time has allowed us to identify the occurrence of basic magmatism at the Paleo- and Eoarchean boundary in the Bug region. The age of 2845 ± 65 Ma dates the imposed metamorphism manifested everywhere in the Bug region that led to considerable amphibolization and partial melting of the rock.