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The paper investigates commercially pure titanium VT1-0 (US analog Grade 2) in the ultrafine grain state after the aluminum ion implantation at a fluence of 1∙1017, 5∙1017 and 10∙1017 ion/cm2. The investigation techniques include X-ray diffraction analysis, scanning electron microscopy with energy dispersive X-ray analysis, and transmission electron microscopy. Auger electron spectrometer is used to analyze the chemical composition of the implanted layer. The grain size in the longitudinal and transverse directions and the phase composition of ultrafine titanium are studied depending on the irradiation exposure. It is found that the ion implantation leads to the formation of such intermetallic compounds as Al3Ti and AlTi3 phases, β-phase titanium and aluminum oxide (Al2O3). The increased irradiation exposure results in the formation of a thicker implanted layer without changing its phase composition.

Using the transmission electron microscopy of thin foils the paper studies the phase composition and fine structure of 0.18С–1Cr–3Ni–1Mo–Fe steel after plasma electrolytic carbonitriding carried out through the surface saturation with nitrogen and carbon. The steel specimens are studied before and after carbonitriding on the surface and at a ~40 μm distance from the surface. It is found that carbonitriding causes significant qualitative and quantitative changes in the steel structure. Thus, the layers of residual austenite appear along the boundaries of martensitic lamellas, and the particles of alloyed cementite and carbonitrides are observed inside the lamellas. The layers of residual austenite locate at a ~40 μm depth along the boundaries of all martensitic crystals, while inside the crystals there are only particles of alloyed cementite and carbonitride M23(C, N)6. The control parameter of changes in the structure and phase composition is the concentration of interstitial atoms of carbon and nitrogen. Changes in this concentration lead to the system deviation from thermodynamic equilibrium. The transition of system to equilibrium or quasi-equilibrium states is considered to be performed through the transition of crystal lattices, which form a gradient structural-unstable state of the matrix, intermetallics and carbonitride compounds, to a low-stability state.

We studied the effectiveness of anti-tuberculosis vaccination with BCG in mice of inbred strains and F1 hybrids (highly resistant to tuberculosis infection) that represent a wide range of genetically determined differences in susceptibility to infection with virulent Mycobacterium tuberculosis. The greatest relative effect was found in susceptible mice, with the exception of highly susceptible I/St mice that were practically not protected by vaccination. Despite significant effect of vaccination in inbred mice, their resistance to M. tuberculosis infection did not exceed that of non-vaccinated highly resistant F1 hybrids.

The paper studies the structure and phase composition of steel 0.12C–1Cr–1Mo–1V–Fe (grade DIN 14MoV63) after a long-term operation using the transmission electron microscopyю Investigated are the nontreated specimen (not subjected to operation) and specimens after a long-term operation with and without fracture. The phase composition and morphology of the steel structure are determined for each specimen. It is found that the steel servicing leads to the destruction of lamellar perlite, intensive fragmentation of ferrite, redistribution of the carbide component and elastic distortion of the crystal lattice.

The principle of operation and the characteristics of the experimental equipment intended for the generation of boron ion plasma and beams are presented. The equipment comprises a vacuum arc source of boron ions with boron isotope separation in a magnetic field and a plasma generator for deposition of boron-containing coatings based on a planar magnetron sputter. Common to this equipment is the use of lanthanum hexaboride cathodes, but for planar magnetron, a pure boron cathode heated in the discharge is also used. It is shown that, when silicon wafer is implanted with beams of 10B+ and 11B+ boron isotope ions with doses of 1014–1016 ion/cm2, the isotopic effect of the diode properties of the implanted surface is observed. The results of studies of the properties of the obtained boron-containing coatings on model materials: stainless steel, crystal silicon, and E110 (Zr–1Nb) reactor alloy are presented.

The paper presents the transmission electron microscopy investigations of the structure and phase composition of ferritic-perlitic ST2 steel surface after electrolytic plasma quenching. The steel in the initial state represents the material after hardening at 890°С for 2 or 2.5 hours and quenching in warm (30–60°С) water with subsequent tempering at 580°C for 2.5 or 3 hours. Electrolytic plasma quenching is carried out at 850–900°С in an aqueous salt solution for 4 seconds, at 320 V voltage and 40 A current. In the initial state, the morphology of the steel matrix consists of lamellar perlite and nonfragmented and fragmented ferrite. Electrolytic plasma quenching of the steel surface results in the martensite transformation, steel self-tempering, and the formation of cementite particles in all martensite crystals. This treatment also leads to the diffusion transformation of γ → α phases, the release of residual austenite (γ -phase) along the low-temperature martensite laths and lamellas and in all crystals of lamellar martensite, the formation of М23С6 special carbides and, finally, to the enhancement of all parameters of the steel fine structure.

The paper presents the transmission electron microscopy investigations of the microstructure and phase composition of the nickel-based superalloy after high temperature annealing. All states of the superalloy are characterized by the single-crystal structure with [001] crystallographic orientation. The Ni–Al–Co alloy system also contains such elements as Mo, Cr, W, Ta, Re and Ru. The Ni–Al–Co system is studied in four states: initial (after directional crystallization) and after 1000°С annealing during 118, 372 and 1274 hours. The major phases forming the alloy system are γ- and γ′-phases. After annealing for 118 hours, the formation of Al6(Re, Ru) phase is observed. After longer high-temperature annealing new phases occur, such as σ-, δ- and Laves phase. The obtained alloy microstructure is classified into four types: 1) γ′-phase quasi-cuboids with γ-phase layers, 2) ribbon anisotropic microstructure of γ′+ γ-phase, 3) ribbon anisotropic microstructure with σ-phase particles in γ-phase layers, 4) γ-phase with δ-phase and Laves phase inclusions. The introduction of a large amount of various alloying elements and the annealing process modify the crystallographic texture of the superalloy.

The paper presents the transmission electron microscopy (TEM) investigations of the thin film structure and phase composition of the heat-affected zone (HAZ) of a weld joint produced by manual metal arc welding (MMAW) of 0.12C–18Cr–10Ni–1Ti–Fe austenite steel exposed then to plastic deformation. The test machine INSTRON-1185 is used to perform quasi-static tensile tests at room temperature and a 1.7∙10–4 s–1 strain rate up to 5 and 37% deformations. TEM investigations are carried out within the HAZ, at a 1 mm distance to the weld line, in the direction of the parent metal and at 0.5 mm distance to the weld deposit. It is shown that MMAW results in the formation of e-martensite both in the parent metal and weld deposit regions. In the latter, γ → e phase transformation occurs faster. Plastic strain ranging between 0–5% throughout the HAZ leads to further γ → e phase transformation. In the weld deposit of the HAZ region, this phase transformation is also more intensive. Further increase in the degree of plastic strain from 5 to 37% results in γ → e → α phase transformation and an elastoplastic lattice distortion of the α-phase. The plastic flexure remains in the crystal lattice of the γ-phase. The bulk material in the HAZ region satisfies the following conditions: scalar dislocation density is higher than the excess, and internal shear stresses are higher than long-ranging.

We have demonstrated that long-term exposure of intact mice to rifampicin (6 months) induces resistance to this drug, which manifested in inability of rifampicin to suppress the growth of Mycobacterium tuberculosis in the lungs and spleen during subsequent infection. It the same time, isoniazid is still effective in these mice. In this case, the phenomenon of somatic resistance to rifampicin in mice was observed if the treatment was started in a short period (within 4 days) after infection with M. tuberculosis. If the interval between infection and rifampicin administration was longer (3 weeks), the resistance disappeared.

Infectious process even at the initial stage after aerosol infection with Mycobacterium tuberculosis induced rapid changes in vaginal microbiota in mice. Rapid decrease in both the quantity and diversity of microbiota was noted, and then, partial recovery of normal flora was observed. Changes in vaginal microbiota was detected as soon as in 3-7 days after lung infection, while inflammatory changes appeared by day 35. At the early stage of infection, no signs of inflammation were observed, neither M. tuberculosis nor its DNA were detected in mouse genital organs.

The paper presents research into the structure and phase composition of Ni–Al–Co alloy modified by rhenium (~3 аt.%) alloying. Observations are carried out using the transmission electron microscopy. The initial state of the alloy is the state after the directional crystallization. The alloy is further subjected to 900°С annealing during 1143 h. Creep tests are additionally carried out for this alloy at the same temperature and time and 400 MPa load. It is shown that FCC disordered γ- and ordered γ′-phases are major in all alloy states. Secondary phases are found to be σ-phase, χ-phase, Laves and AlRe2 phases. Experiments show that the high temperature annealing changes the phase composition of the alloy. Thus, the amount of the ordered γ′-phase increases, while that of disordered γ-phase decreases. During the creep process, the amount of the former reduces and the amount of the latter increases. The annealing process modifies the phase composition in secondary phases. It is found that the structural modification caused by the creep process differs from that caused by the annealing process. Thus, the creep-induced modification of the cuboid structure in γ′-phase is stronger than due to annealing. Dislocations are observed in γ- and γ′-phases in all states of the alloy. During the annealing process, the dislocation density in γ-phase is higher than in γ′-phase, and vice versa during the creep process. The experiments show that the behavior of the dislocation structures is different during the annealing and creep processes.

Using the methods of electron diffraction microscopy and X-ray diffraction analysis, the influence of alloying of the austenitic steel, Grade 110H13, with chromium and vanadium, as well as high-melting, ultrafine-grained TiO2, ZrO2 powders and Na3AlF6 cryolite on its structural-phase state and microstructure is investigated. It is shown that the matrix of non-modified steel is completely austenitic and consists of an iron-based solid solution and the interstitial (C, N, O and other) and substitutional (Cr, V and other) atoms simultaneously. Alloying with chromium and vanadium changes neither its phase composition nor defect structure, while alloy modification results in qualitatively new structural features: γ → e-transformation, high-intensity microtwinning, defect structure changes, and a sharp increase in the scalar dislocation density. The features of the deformation-induced microtwinning and e-martensite plates identified in the modified steel promote revealing additional microtwin systems in the matrix γ-phase, which result in structural changes making it possible to classify it as a γ′-phase. It is found out that an introduction of modifying additions gives rise to the following sequence of structural-phase transformations: γ→γ′→(γ′ +e). The experimental data obtained demonstrate that as a result of modification the crystal lattice transits into a low-stability state. This transition is accompanied by marked structural-phase changes consisting in the formation of several microtwin systems and γ → e-transformation. These structural-phase changes in the modified steel are due to the crystal-lattice transition into the low-stability state, followed by new structural-phase alterations.

Using transmission electron microscopy and X-ray diffraction analysis, the structural-phase state of steel 0.1C–2V–1Ti–Fe, deformed by the SPD methods and subjected to high-temperature annealing at the temperatures 600 and 700°С, is investigated. The influence of the steady temperature on the grain size, steel phase composition, carbide transformations, carbide particle size and distribution density, carbon distribution, and fine-structure parameters are determined. A special focus is made on the sources of internal stress.

The paper presents the transmission and the scanning electron microscope investigations of the phase composition and fine structure of Ni–Al–Cr-based alloy alloyed by rhenium and lanthanum. The alloy is prepared by the directional crystallization technique and then subjected to 1150°С annealing during 1 hour. It is shown that γ- and γ′-phases are major and have a face-centered cubic crystal system. Solid solutions of γ- and γ′-phase have a disordered and an ordered atom arrangement, respectively. The latter has L12 superstructure. It is found that rhenium and lanthanum alloying leads to the structural modification of γ′-phase quasi-cuboids. Not dissolving in major phases, rhenium and lanthanum are phase-formation elements and form σ-phase. The phase composition and morphology of these phases are studied and described.

of electron microscopic study of Ni–Cr–Al based superalloy are presented. The superalloy prepared by the method of directed crystallization is investigated in the initial state and after creep for 10 h at Т = 1100°С and σ = 100 MPa. It is established that the alloy in both states is formed by γ and γ' phases based on the FCC crystal lattice; the γ' phase has ordered arrangement of atoms (the L12 superstructure) and is the main phase in all states. The phase composition and morphology are studied. The change in the phase composition and particle sizes of phases as a result of creep is analyzed. The influence of the high-temperature creep on the superalloy structure is established.

A comparative testing of complex catalysts with homo and hetero combinations of chiral and achiral monodentate phosphite- and phosphine-type ligands in the Ir-catalyzed asymmetric direct reductive amination of 2,3,4,9-tetrahydro-1H-сarbozol-1-ones was carried out. A positive effect of the use in the reaction of a mixture of chiral and achiral ligands was demonstrated. This approach makes feasible a one-pot synthesis of valuable biologically active compounds of (tetrahydro-1H-carbazol-1-yl)amine series.

The results of an investigation of the metrological characteristics of a standard, which can store, reproduce and transfer the unit of average power from 0.1 mW to 5 mW in the 0.6–1.7 μm spectral range with a relative expanded uncertainty not exceeding 0.002, and an attenuation from 0.05 dB to 60.00 dB, with an expanded uncertainty of less than 0.2 dB, are presented.

Scientific work on obtaining pigments of different colors from the ‘red sludge’ at the Bogoslovskii Aluminum Plant has been performed. Atechnology for producing red pigments (heat treatment at 290 – 850°C) and black pigments (heat treatment in a controlled atmosphere at temperature 500 – 1000°C) has been developed. Ceramic pigments with the crystal lattice structure of chain pyroxenes and garnets are obtained from red sludge at temperatures 900 – 1100°C. These investigations are aimed at expanding the raw materials base of pigments and reducing their production costs by recycling the wastes.

Mutations in the X-chromosomal L1CAM gene lead to severe neurological deficits. In this study, we analyzed brains of female mice heterozygous for L1 (L1+/-) to gain insights into the brain structure of human females carrying one mutated L1 allele. From postnatal day 7 onward into adulthood, L1+/- female mice show an increased density of neurons in the neocortex and basal ganglia in comparison to wild-type (L1+/+) mice, correlating with enhanced metabolic parameters as measured in vivo. The densities of astrocytes and parvalbumin immunoreactive interneurons were not altered. No significant differences between L1+/- and L1+/+ mice were seen for cell proliferation in the cortex during embryonic days 11.5-15.5. Neuronal differentiation as estimated by analysis of doublecortin-immunoreactive cortical cells of embryonic brains was similar in L1+/- and L1+/+ mice. Interestingly, at postnatal days 3 and 5, apoptosis was reduced in L1+/- compared to L1+/+ mice. We suggest that reduced apoptosis leads to increased neuronal density in adult L1+/- mice. In conclusion, L1+/- mice display an unexpected phenotype that is not an intermediate between L1+/+ mice and mice deficient in L1 (L1-/y), but a novel phenotype which is challenging to understand regarding its underlying molecular and cellular mechanisms.

The ventral tegmental area (VTA) and nucleus accumbens (NAc) are essential for learning about environmental stimuli associated with motivationally relevant outcomes. The task of signalling such events, both rewarding and aversive, from the VTA to the NAc has largely been ascribed to dopamine neurons. The VTA also contains GABA (γ-aminobutyric acid)-releasing neurons, which provide local inhibition and also project to the NAc. However, the cellular targets and functional importance of this long-range inhibitory projection have not been ascertained. Here we show that GABA-releasing neurons of the VTA that project to the NAc (VTA GABA projection neurons) inhibit accumbal cholinergic interneurons (CINs) to enhance stimulus-outcome learning. Combining optogenetics with structural imaging and electrophysiology, we found that VTA GABA projection neurons selectively target NAc CINs, forming multiple symmetrical synaptic contacts that generated inhibitory postsynaptic currents. This is remarkable considering that CINs represent a very small population of all accumbal neurons, and provide the primary source of cholinergic tone in the NAc. Brief activation of this projection was sufficient to halt the spontaneous activity of NAc CINs, resembling the pause recorded in animals learning stimulus-outcome associations. Indeed, we found that forcing CINs to pause in behaving mice enhanced discrimination of a motivationally important stimulus that had been associated with an aversive outcome. Our results demonstrate that VTA GABA projection neurons, through their selective targeting of accumbal CINs, provide a novel route through which the VTA communicates saliency to the NAc. VTA GABA projection neurons thus emerge as orchestrators of dopaminergic and cholinergic modulation in the NAc.

A comparative morphometric analysis of electron photomicrographs of the presynaptic terminals in cultured in vitro for 7 days CA1 hippocampal slices from 7-day-old rats and in the hippocampi of 14-day-old rats was conducted. As compared with the terminals of intact neurons, the terminals of cultured cells were larger and contained a greater amount of synaptic vesicles, which, however, to a lesser extent were united in clusters. Distributions of the vesicle profiles in cultured slices were characterized by a greater distance to the nearest neighbor. Obviously, such structural features should be taken into account when interpreting data obtained in electrophysiological studies on hippocampal slice cultures.

We analyzed structural rearrangements of synaptic contacts in the stratum radiatum of the CA1 area of cultured rat hippocampal slices under conditions of the development of potentiation of synaptic transmission induced by short-term (10 min) oxygen-glucose deprivation (OGD). Studies were carried out using electron microscopy and 3D reconstruction of cellular compartments. Within the 1st h after OGD, we observed increases in the volume of pre-synaptic terminals and post-synaptic spines and also in the area of postsynaptic densities (PSDs) in both asymmetric excitatory and symmetric inhibitory synapses, especially in the case were the PSD was perforated. We also observed significant activation of glial cells (increases in their volume and area of contacts of their processes with the components of synapses). Therefore, OGD results in activationassociated structural rearrangements of both excitatory and inhibitory synapses of the hippocampal CA1 area. Such rearrangements are accompanied by a clearly pronounced reaction of the glia, which correlates with an important role of the latter in modulation of the functioning of neurons.

A method is proposed for determining the thickness of thin (0.1–5.0 µm) polymer layers and coatings by means of infrared frustrated total internal reflection (FTIR) spectroscopy. This method is based on an analytic expression derived for the dependence of the intensities of absorption bands in IR FTIR spectra on the thickness of a polymer layer. The method is tested on model samples consisting of a thick film of polyethylene terephthalate with a layer of different thicknesses of polystyrene deposited on it. The advantage of this method is the ability to determine the thickness of thin polymer layers deposited on bulk or opaque polymer substrates.

The article presents a formula for estimating the component of uncertainty in the measurement of the relative statistical fluctuation of the power of laser radiation caused by a finite number of measurements of power on the basis of which instability is determined. The influence of drift on the measured radiation power is established and a formula for adding the drift and fluctuation components of the relative statistical fluctuation is checked.

The ultrastructure of symmetric (putatively inhibitory) axo-dendritic synapses on the membrane of hippocampal CA1 pyramidal neurons was investigated in young (20-day-old) and adult (1-year-old) mice. It was shown that synapses of adult animals contain, on average, fewer synaptic vesicles (SVs), and resting SVs of the reserve pool are mostly responsible for this difference. At the same time, in the synapses of adult mice SVs are localized closer to active zones, and the readily releasable pool of SVs is larger in these animals than in young mice. The observed changes in the spatial structure of SV pools presumably demonstrate the age-associated adaptation of inhibitory synapses providing the maintenance of adequate functional properties of hippocampal neuronal networks.

Within the framework of the quantum hypothesis of synaptic transmission, the amount of a neurotransmitter released in a unitary event of calcium-dependent exocytosis corresponds to the content of a synaptic vesicle (SV). The number of these organelles in the presynaptic terminal is an important index characterizing the functional state of the given synapse. The technique of estimation of the dimension of the total SV pool, which is based on mathematical modeling and is realized in a computer experiment, is described. This technique allows one to interpret quantitative estimations obtained in the course of the analysis of images of random ultrathin sections of presynaptic terminals in the terms of 3D space. The capabilities of this technique are illustrated using an example of estimation of the size of the total SV pool in asymmetric synapses between neurons of the radial layer of the murine hippocampal CA1 area.