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The key synthetic stage (cyclization) of 9-(2-diethylaminoethyl)-2-phenylimidazo[1,2-α]benzimidazole dinitrate, which possesses antiulcer activity, was improved by changing the reaction medium and using the imine itself rather than its hydrobromide for the cyclization. A method using the physicochemical properties (NMR and IR spectroscopy and UV spectrophotometry) of the substance was proposed for identifying it. An HPLC method was proposed for determining related impurities; nonaqueous titration, for quantitative determination. Acute toxicity was studied in mice and rats upon intragastric and intravenous administration. The results showed that the drug substance had class 3 moderate toxicity upon both intragastric and intravenous administration.

The antioxidant formulation ethylmethylhydroxypyridine succinate (Mexidol) effectively neutralizes the radiolysis products of water and oxidative damage to DNA and proteins induced by X-irradiation. This substance was found to affect the formation of long-lived reactive forms of albumins and globulins and their degradation, which is accompanied by generation of hydrogen peroxide and an increase in the duration of oxidative stress after irradiation. Ethylmethylhydroxypyridine succinate has gene-protective and radiomitigating actions in vivo, decreasing the formation of micronuclei in polychromatophilic erythrocytes from red bone marrow in mice after irradiation, and is a potential therapeutic radiomitigating agent for preventing adverse effects due to impairments of redox homeostasis after irradiation.

Radioactive wastes are formed during the production of uranium-plutonium nuclear fuel at enterprises. In the present article the concentration ranges for uranium, plutonium, and neptunium in liquid and cemented wastes corresponding to different radioactivity classes are determined. The concentration ranges are determined for wastes formed in the production of nitride fuel for the initial load, as well as for waste formed on use of recycled uranium, plutonium, and neptunium in production. The effect of 241Am accumulation on the classification of radwaste is determined. The estimated cost of transferring the wastes formed on fabrication of mixed nitride fuel to the national operator for disposal is presented. The technological methods of reducing the cost of waste disposal, including the possibility of forming class-3 wastes for which surface disposal is admissible, are presented. The maximum concentration of plutonium and americium in liquid wastes at which the solidified forms of wastes correspond to class-3 is determined.

Morphological, morphometric, and ultrastructural analysis of the nerve fibers in the colon mucosa was performed in C57BL/6 mice at various terms of development of acute colitis induced by dextran sodium sulphate. The nerve fibers were labeled with antibodies to pan-neuronal marker βIII-tubulin. The progression of inflammatory and ulcerative processes in the mucosa on days 3-5 was associated with hyperplasia and hypertrophy of nerve fibers that peaked on day 7 after colitis induction. Ultrastructural analysis at all terms of colitis development showed moderate degeneration of axons. Thus, hypertrophy and hyperplasia of the nervous fibers in colon mucosa in experimental acute colitis correlated with aggravation of the ulcerative process in the mucosa. These changes are determined by alteration of histoarchitectonics and regenerative processes in the mucosa.

An approach to increasing the diagnostic accuracy of the ECG stress test for transient myocardial ischemia is considered. It is proposed to modify the decision rule by including an additional procedure for assessing the temporal dynamics of the equivalent cardiac generator in the ST-T segment. The results of evaluating the sensitivity and specificity of diagnosis in a group of subjects are presented.

A measurement facility for reproduction of the unit of sound pressure in water at frequencies of 1–500 Hz over the temperature range 0.5–35°C is featured for excess static pressures to 60 MPa. The objective of creating an installation is to extend the functional capabilities of the GET 55-2017 State Primary Standard of units of sound pressure and sound particle velocity in a water medium. The feasibility of model operation in GET 55-2017 of the operating conditions of using a hydrophone is shown. The principles of operation and the metrological characteristics of the created installation are examined. The special features of the measurement procedure of calibration of a hydrophone are given.

The paper presents the results of forming rifts in five-layer fiber reinforced metal polymer laminates by electromagnetic forming. During the experimental studies the discharge energy of the electro-magnetic machine was varied in such a way as to achieve different depths of the rift. Samples obtained by electro-magnetic forming were compared with control samples obtained by forming using a rubber pad under static loading. The strain state of the samples was analyzed using an digital image correlation system Vic-3D. The experimental research of fiber reinforced metal laminates forming under the influence of pulse magnetic field has shown the possibility of formability increasing due to change of strain state: the rift zone is dominated by compressive circumferential strains, rather than tensile radial strains as during conventional rubber pad forming.

Monolayer transition metal dichalcogenides (1L-TMDs) have tremendous potential as atomically thin, direct bandgap semiconductors that can be used as convenient building blocks for quantum photonic devices. However, the short exciton lifetime due to the defect traps and the strong exciton-exciton interaction in TMDs has significantly limited the efficiency of exciton emission from this class of materials. Here, we show that exciton-exciton interaction in 1L-WS2 can be effectively screened using an ultra-flat Au film substrate separated by multilayers of hexagonal boron nitride. Under this geometry, induced dipolar exciton-exciton interaction becomes quadrupole-quadrupole interaction because of effective image dipoles formed within the metal. The suppressed exciton-exciton interaction leads to a significantly improved quantum yield by an order of magnitude, which is also accompanied by a reduction in the exciton-exciton annihilation (EEA) rate, as confirmed by time-resolved optical measurements. A theoretical model accounting for the screening of the dipole-dipole interaction is in a good agreement with the dependence of EEA on exciton densities. Our results suggest that fundamental EEA processes in the TMD can be engineered through proximal metallic screening, which represents a practical approach towards high-efficiency 2D light emitters., The short exciton lifetime and strong exciton-exciton interaction in transition metal dichalcogenides limit the efficiency of exciton emission. Here, the authors show that exciton-exciton interaction in monolayer WS2 can be screened using proximal metal plates, leading to an improved quantum yield.

We compared phagocytic activity of macrophages of monocyte origin and Kupffer cells under the influence of M1 and M2 inducers and without activation. Cultures of monocyte-derived macrophages and Kupffer cells were characterized by intensive expression of CD68 that was not affected by activation factors. At the same time, these cultures demonstrated different dynamics of phagocytic activity. Monocyte-derived macrophages initially had more pronounced absorption capacity that gradually increased during the experiment. Kupffer cells were characterized by abrupt fluctuations of phagocytic activity: sharp growth and rapid saturation. Despite these differences, the endosomes produced by monocyte-derived macrophages and Kupffer cells had similar degrees of maturity.

Mekler's construction gives an interpretation of any structure in a finite relational language in a group (nilpotent of class $2$ and exponent $p>2$, but not finitely generated in general). Even though this construction is not a bi-interpretation, it is known to preserve some model-theoretic tameness properties of the original structure including stability and simplicity. We demonstrate that $k$-dependence of the theory is preserved, for all $k \in \mathbb{N}$, and that NTP$_2$ is preserved. We apply this result to obtain first examples of strictly $k$-dependent groups (with no additional structure).

Results of studies carried out in the period from 2015 to 2017 as part of efforts to improve GET 132–99, the State Primary Standard of the unit of specific electrical conductivity of liquids, are presented. The structure of GET 132–2018, the new approved State Primary Standard of the unit of specific electrical conductivity of liquids in the range from 0.1 to 50 mho/m is described. Solutions by means of which the metrological characteristics of the primary standard may be improved are presented.

We establish a cutting lemma for definable families of sets in distal structures, as well as the optimality of the distal cell decomposition for definable families of sets on the plane in $o$-minimal expansions of fields. Using it, we generalize the results in [J. Fox, J. Pach, A. Sheffer, A. Suk, and J. Zahl. "A semi-algebraic version of Zarankiewicz's problem"] on the semialgebraic planar Zarankiewicz problem to arbitrary $o$-minimal structures, in particular obtaining an $o$-minimal generalization of the Szemer\'edi-Trotter theorem.

The results of studying electrical and gas sensitive characteristics of H2 sensors based on thin nanocrystalline SnO2 films with the Pt, Pd, and Ag dispersed layers deposited on the surface and Ag, Y, and Ag + Y additives in the volume are presented. It is shown that various combinations of catalysts on the surface and in the volume have a significant effect on the microstructure of films and density of oxygen adsorption sites on the surface of tin dioxide. As a result, the resistance values of sensors in clean air R0, activation energies of the temperature dependences of R0, responses to hydrogen in the concentration range of 50–2000 ppm are different. Studies performed by the method of UV-visible spectroscopy revealed in the absorption spectra of films with a silver addition in the volume a band of surface plasmon resonance of silver indicating that the additive is present in the form of metallic Ag nanoparticles. Particular attention was paid to the influence of long-term tests on the properties of sensors with the listed additives. It was established that the joint introduction of Ag+Y into the volume of films prevents the increase of the resistance and responses during prolonged exposure to hydrogen, which is observed during the operation of all other samples studied. Possible mechanisms for changing the sensors’ properties during testing and the role of additives in their stabilization are considered.

The RBMK design-stage service life was assumed to be 30 years. Ten power-generating units have now exceeded this limit. Service life extension of nuclear power plants is a common practice in countries using nuclear energy. This approach was also applied to power-generating units with RBMK-1000 with servicelife extension to 45 years or more. To maintain electricity production in NPPs with RBMK, a technology for restoring the service-life characteristics was developed and implemented in the No. 1 unit of the Leningradskaya NPP. The results of the adoption of this technology in combination with experimental and computational validation of safety made it possible to extend the operation of the No. 1 unit of the Leningradskaya NPP in the power-generation mode since December 2013. Similar work was subsequently successfully completed in other power-generating units with RBMK.

The results of studies of electrical and gas sensitive characteristics of acetone sensors based on thin nanocrystalline SnO2 films with various catalysts deposited on the surface (Pt/Pd, Au) and introduced into the volume (Au, Ni, Co) are presented. Films containing impurities of gold and 3d-metals were obtained by the method of magnetron sputtering of mosaic targets. Particular attention was paid to the influence of the longterm tests and humidity level on the properties of sensors. It is shown that the sensors with the deposited dispersed gold layers with Au+Ni and, especially, Au+Co additives introduced into the volume are characterized by the increased stability in the process of testing under prolonged exposure to acetone and also under conditions of varying humidity.

The results of Investigations of the nitrogen and uranium pressure in the system U–Zr–C–N in the temperature range 1873–2073 K and the constructed section of the U–Zr–C–N phase diagram at 1873 K are presented. The behavior of the solid fission products in carbonitride fuel, the interaction of the fuel with a pyrolytic carbon coating, and the behavior of micro fuel elements based on such fuel during high temperature firing and in the presence of a temperature gradient are examined. The conditions for the preparation of fuel compositions of the type uranium carbonitride in a carbide-silicon matrix and some of its physicochemical and mechanical properties are determined. It is noted that there is promise in using fuel compositions and micro fuel elements based on uranium-zirconium carbonitride for high-temperature applications.

Time dependences in the thermo-cyclic mode of the conductivity of CO sensors, constructed in a traditional four-electrode and a planar three-electrode design on the basis of thin nanocrystalline tin dioxide films, are analyzed. The analysis showed that the use of the Pt/Pd/SnO2:Sb sensors in a planar design in the thermocyclic mode with a long cooling cycle makes it possible to detect smoldering products at a significant reduction of power consumption.

Lectin (PYL) of molecular mass 17,154.5 Da that exhibited Gal/GalNAc-specificity was isolated from the scallop Patinopecten yessoensis. The lectin was completely inactivated by heating to 60°C for 30 min, exhibited the greatest activity at pH 5–9, and was metal-independent. It was shown that the lectin was involved in the mollusk protective mechanism by agglutinating the Gram-negative bacterium Vibrio proteolyticus.

The heats of dissolution of crystalline amino acid in water and potassium hydroxide solutions at 298.15 K were measured by direct calorimetry. The standard enthalpies of formation of l-lysine and the products of its dissociation in aqueous solutions were calculated.

The effect of hydrogen sulfide in the concentration range of 0–100 ppm on the characteristics of thin films of tin dioxide and tungsten trioxide obtained by the methods of magnetron deposition and modified with gold in the bulk and on the surface is studied. The impurities of antimony and nickel have been additionally introduced into the SnO2 bulk. An optimal operating temperature of sensors 350°C was determined, at which there is a satisfactory correlation between the values of the response to H2S and the response time. Degradation of the sensor characteristics is investigated in the long-term (~0.5–1.5 years) tests at operating temperature and periodic exposure to hydrogen sulfide, as well as after conservation of samples in the laboratory air. It is shown that for the fabrication of H2S sensors, the most promising are thin nanocrystalline Au/WO3:Au films characterized by a linear concentration dependence of the response and high stability of parameters during exploitation.

The electrical and gas-sensitive characteristics of sensors based on nanocrystalline SnO2 thin films with noble metals (Pt, Pd, Au) and 3d-transition metals (Co, Ni) additives in the bulk and on the surface have been studied. Thin (~100 nm) tin dioxide films were grown in magnetron by DC sputtering of a tin–antimony alloy target in oxygen–argon plasma. It was shown that the obtained sensors can detect acetone and ethanol vapors at 1 ppm level. The detecting of acetone vapors needs higher temperatures than detecting of ethanol. In a temperature range T 700 K, the sensors with deposited Pt, Pd catalysts on the surface as well as the sensors with Ni and Co additives in the bulk are characterized by a higher sensitivity to acetone than to ethanol. The use of different operating temperatures allows detecting selectively acetone and ethanol vapors.