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Clinical physiology involves a complete, comprehensive, multilateral study of the functions of both affected and healthy organs, which allows us to assess the compensatory capabilities of the body. Artificial intelligence is increasingly being used in medicine, including in clinical physiology. This is facilitated by the increase in computing processing power, development of cloud services and datasets, and numerous scientific articles demonstrating the effectiveness and viability of such intelligent solutions. Although the approach to medical dataset development is generally similar, there are a number of key features and significant differences in clinical physiology. Artificial intelligence systems in clinical physiology may be effectively trained and applied in practice by following the recommendations in this study. The national standard of the Russian Federation GOST R 59921.9-2022, which has entered into force, is included in the set of standards Artificial Intelligence systems in clinical medicine and establishes additional requirements for data analysis algorithms and test methods of artificial intelligence systems used in the field of clinical physiology. A crucial feature of the created standard is its qualimetric type (i.e., it has a mandatory set of demonstration data). Russia is one of the first countries to start developing quasi-metric standards worldwide, and 15 industry standards in the field of artificial intelligence (2 of them in medicine) will come into force this year.

Introduction. Major projects in the oil refining industry require the involvement of contractors. Cooperation with qualified and responsible contractors can be considered as a competitive advantage, allowing timely delivery of objects with the proper level of quality and safety.Significant injury rates in contracting organizations operating at oil refining facilities attract attention. This leads to an interest in safety of working conditions in the industry. One of the approaches to solving the problem is to use the occupational health and safety management system in the interactions of the customer and the contractor.Problem Statement. The objective of this study is to improve the mechanism of rating contractors from the point of view of occupational and industrial safety.Theoretical Part. The paper uses the official statistical reports on injuries and the data on injuries of employees of contracting organizations at an oil refinery of a large Russian company. A mechanism for rating contractors in this area has been developed. It includes three sections with their own criteria and weight coefficients. The automatically generated and periodically updated rating is proposed to be placed in open access on the website of the Federal Service for Labor and Employment.Conclusions. The use of the proposed rating will allow customers working in the field of oil refining to reasonably judge the risks generated by the industrial safety system of potential contractors.

The cost of thermophotovoltaic converters can be reduced by making substrates of amorphous materials, which do not have an orienting effect, such as glass or fused quartz, for obtaining thin polycrystalline GaSb layers. The study establishes the conditions for the crystallization of thin polycrystalline GaSb layers with grain size sufficient to produce efficient thermophotovoltaic converter structures on a non-orienting substrate made of fused quartz. The authors carry out a two-dimensional modeling of the initial nucleus growth to study how the crystallization conditions affect the shape of the grains. It is shown that the form of grain growth is not very sensitive to the initial nucleus size and cooling rate, but is rather sensitive to nucleus density on the surface. The paper provides an estimate of the average surface density of the new phase nuclei, which tend to grow, on substrate surfaces. When the temperature is increased, the surface concentration of nuclei grows, and the grain size decreases. It is determined that the selected range of grain surface density corresponds to the cultivation temperature range of 450—550°С. Thin polycrystalline GaSb layers are grown at 520°С with a cooling rate of 10°C/ min to a temperature of 400°C, using a method developed by us, which requires simple equipment and consists in the forced cooling of a thin layer of stibium in a gallium melt in a vacuum. The degree of crystallinity of the samples is estimated from the photoluminescence spectra at 77 K. The spectra show two emission bands: one at 796 meV and another, the predominant one, at 775 meV, which indicates the presence of a significant number of point defects and deviations from the stoichiometry of the obtained films. The studies performed on an interference microscope show that the obtained layers have good planarity and homogeneity, and the average grain size is up to 25 microns, which confirms the validity of the proposed models. This technology can be used to manufacture inexpensive infrared radiation converters and, in particular, thermophotovoltaic converters.

A new insight into capillary channel formation with a high aspect ratio in the translucent matter by nanosecond UV laser pulses is discussed based on our experiments on KrF laser multi-pulse drilling of polymethyl methacrylate and K8 silica glass. The proposed mechanism includes self-consistent laser beam filamentation along a small UV light penetration depth caused by a local refraction index increase due to material densification by both UV and ablation pressure, followed by filamentation-assisted ablation. A similar mechanism was shown to be realized in highly transparent media, i.e., KU-1 glass with a multiphoton absorption switched on instead of linear absorption. Waveguide laser beam propagation in long capillary channels was considered for direct electron acceleration by high-power laser pulses and nonlinear compression of excimer laser pulses into the picosecond range.

The main male hormone, testosterone is obtained from cheap and readily available phytosterol using the strains of Mycolicibacterium neoaurum VKM Ac-1815D, or Ac-1816D. During the first “oxidative” stage, phytosterol (5–10 g/L) was aerobically converted by Ac-1815D, or Ac-1816D to form 17-ketoandrostanes: androstenedione, or androstadienedione, respectively. At the same bioreactor, the 17-ketoandrostanes were further transformed to testosterone due to the presence of 17β-hydroxysteroid dehydrogenase activity in the strains (“reductive” mode). The conditions favorable for “oxidative” and “reductive” stages have been revealed to increase the final testosterone yield. Glucose supplement and microaerophilic conditions during the “reductive” mode ensured increased testosterone production by mycolicibacteria cells. Both strains effectively produced testosterone from phytosterol, but highest ever reported testosterone yield was achieved using M. neoaurum VKM Ac-1815D: 4.59 g/l testosterone was reached from 10 g/l phytosterol thus corresponding to the molar yield of over 66%. The results contribute to the knowledge on phytosterol bioconversion by mycolicibacteria, and are of significance for one-pot testosterone bioproduction from phytosterol bypassing the intermediate isolation of the 17-ketoandrostanes. Graphical Abstract

We report a flexible approach to the synthesis of phenanthrene-like heterocycles through organocatalytic ANRORC (Addition of the Nucleophile, Ring Opening, and Ring Closure) reaction of electron-deficient 3-vinylchromones with cyanoacetamide. Addition of highly basic DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) or tetramethylguanidine (TMG) at 80 °C leads to chromeno[4,3-b]pyridines in good yields, whereas Et3 N at 20 °C made it possible to obtain the less accessible pyrano[3,2-c]chromenes and their 2-imines. The synthesis proceeds in mild conditions (EtOH, 20-80 °C), is versatile and applicable for a wide scope of reactants. The obtained compounds show bright fluorescence in the range 460-595 nm with high quantum yields (up to 0.84) in various solvents (MeCN, DMSO, EtOH, H2 O).

A procedure has been developed for the synthesis of 6,7-dihydroindazoles and 7,8-dihydroquinazolines by reaction of 3,4-dihydroxanthone derivatives with 1,2- and 1,3-binucleophiles (hydrazine, guanidine). The reaction occurred under mild conditions (methanol, 20-65°C) with high yields.

Mode I fracture of plate specimens with sharp V-shaped notches is studied analytically and numerically. Within computations, elastic-perfectly plastic constitutive behaviour is assumed. The crack initiation from the tip of the V-shaped notch is described with the help of a modified Leonov–Panasyuk–Dugdale model using an additional parameter, namely, the diameter of the plasticity zone. Under small-scale yielding conditions in the presence of a singularity of the stress field in the vicinity of the V-shaped notch tip, a coupled fracture criterion is proposed. A strain-based fracture criterion is formulated at the real notch tip, and a force-based criterion operating with averaged normal stresses is considered at the fictitious crack tip. The diagrams of quasi-brittle fracture of specimens from structured material are constructed. The propagation of the plastic zone in the notched plates under quasi-static loading is simulated numerically. The plastic zone size in the vicinity of the V-shaped notch tip is assessed; in the limiting case, the V-notch degenerates into an edge crack. The generalized stress intensity factor for a crack growing from a sharp V-shaped notch is obtained by the finite element method. It is shown that under small-scale yielding, the analytical predictions of the critical load agree with the numerical results for a wide range of opening angles.

The paper deals with local discrepancies in the problem of the distribution of the sequence $$\{k\alpha\}$$ , i.e., with the remainder terms in asymptotic formulas for the number of points in this sequence lying in prescribed intervals. A construction of intervals for which local discrepancies tend to infinity slower than any given function is presented. Moreover, it is shown that there exists an uncountable set of such intervals. Previously, similar results were obtained only for irrationalities with bounded partial quotients of their continued fraction expansions.

A simple algorithm for reliably determining the Q-factor of an open dielectric resonator made of a material with a tgδ less than 0.0001 in the shielded region is presented, based on measuring the parameters of an electromagnetically coupled system of bulk metal and open dielectric resonators. The analytical substantiation of the considered method for determining the Q-factor of an open dielectric resonator in electrodynamic and electrotechnical representations is carried out. The variants of the influence of the metal volume on the effective Q-factor of an open dielectric resonator depending on its electrophysical characteristics are considered. The factors affecting the effective Q-factor of an open dielectric resonator obtained using this measurement method are evaluated, and the range of expected measurement errors is shown. The advantage of the method for determining the Q-factor of an open dielectric resonator is the high accuracy of the obtained analytical ratios for determining the Q-factor, the absence of increased requirements for the accuracy of the measurement sections and the quality of the internal surfaces of the metal resonator, the simplicity of the measurement process, based on the use of ordinary equipment and element base.

Heterostructures with lattice mismatched and compositionally different layers are widely used in modern electronic and optoelectronic device engineering. Generally such structures are manufactured by the methods of metal-organic vapor phase epitaxy, metal-organic chemical vapor deposition and molecular-beam epitaxy. However, the methods of deposition from a liquid phase are the most inexpensive and simple yet. Thus obtaining the above mentioned heterostructures from a liquid phase is still promising. In this work we demonstrated the possibility of using the method of scanning liquid phase epitaxy to grow continuous heteroepitaxial layers over the substrate surface highly mismatched by lattice constant and having different crystal-chemical properties. By controlling basic parameters of the method we created the conditions close to the solution-melt saturation limit. In other words, we created the conditions of ultra-fast solution-melt cooling and, respectively, high growth rate. We obtained the heterostructures of Ge layers grown on GaP substrates where the lattice mismatch made 3.7%. Gallium was used as the solvent for Germanium. The heterostructure was grown by the method of scanning liquid phase epitaxy in the conditions of ultra-fast initial cooling of the solution-melt. Overcooling at the crystallization front was controlled by an extra heater of the substrate back side. The growing time was 1 and 20 seconds for the two test samples. The layers thickness was determined by the spherical slice technique to be 1.2 and 1.5 μm for these two growing time values, accordingly. We showed that it was possible to obtain more perfect Ge layers on GaP substrate by lowering the growth rate in the final growth stage. This method can be used to grow heterostructures used in creating such modern electronic and optoelectronic devices as structures based on А3В5 compounds and their solid solutions, which cannot be obtained by other classical methods of liquid phase epitaxy due to significant differences in lattice constants and / or crystal-chemical properties.

The temperatures of phase transformations and the oxidation-reduction reactions occurring under heat treatment of composite Al – Si + flux brazing metal used for brazing of Al alloys and produced by the TRILLIUM™ Technology are determined. It is shown that the melting mechanism is stepped and is accompanied by a chemical reaction between the flux and the oxide film and by diffusion transfer of silicon into the substrate. The heat treatment temperature is shown to affect the microstructure in the zone of contact between the brazing metal and the substrate.

We carried out the modelling of separate technological stages of scanning liquid phase epitaxy (SLPE) technique: wetting the substrate by the solution-melt using Ampere force, growing the epitaxial layer during a short-time contact between the substrate and solution-melt, and removing the solution-melt from the substrate using Ampere force as well. The modelling was carried out for the case of Ge layers growing on GaAs substrate from Ga-Ge solution-melt at the temperature 500 °C. We have ascertained that the Peltier effect and Joule heating practically have no effect on the growth pattern and under certain conditions could be even diminished. The influence of electromigration and convection in the solution-melt can be neglected. It has been shown that the basic technological parameters of SLPE process are as follows: the initial temperatures and sizes of the substrate and the growing vessel, the conditions of heat removal from the substrate back side and the time of the process. It has been also shown that the major contribution into the epitaxial layer thickness distribution over the substrate surface has been made by the heat distribution in the cooled substrate.

A number of new pyrazole and pyrimidine derivatives containing an allylmorpholine fragment were obtained by reactions of chromone-containing allylmorpholines with 1,2- and 1,3-binucleophiles (hydrazine, guanidine, acetamidine). The syntheses were carried out under mild conditions (ethanol, room temperature), and the target products were isolated with high yields. The obtained compounds are of interest as potential cholinesterase inhibitors.

The article calculates the analysis of the stress-strain state of the traverse, taking into account additional loads acting in full-scale operating conditions. The presented calculation methodology is based on determining the permissible stresses and modeling the structure using the finite element method. A design scheme, a solid-deformed model have been developed, and a finite element method has been calculated in the CAD / CAE system. To determine the operating values ​​in the steel structure of the lower service, we will construct a model in natural values ​​with observance of the given characteristics and geometrical dimensions. The stress-strain state of the traverse elements is quite complex, since both compressive stresses and tensile stresses arise in one element in different planes, which are interchanged during the operation of the lifting structure. The above calculation and analysis of the strength of the metal structure of the lifting structure showed that this approach is suitable for the development on its basis of expert systems for assessing the lifespan of lifting structures, both at the stage of design and at the stage of operation

Phenomenological constitutive equations contain material parameters which cannot be measured directly in the experiment. We address the problem of error-resistant parameter identification for models of large strain elasto-plasticity. The identification is based on tests with a heterogeneous stress state. A methodology is presented which allows us to assess the reliability of identification strategies in terms of their sensitivity to measurement errors. A vital part of the methodology is the mechanics-based metric in the space of material parameters. The measure of sensitivity is the size of a parameter cloud, computed using this metric. Efficient procedures of Monte Carlo type for computation of the parameter cloud are presented and discussed. The methodology is exemplified in terms of a model with combined nonlinear isotropic-kinematic hardening. First, for an aluminum alloy, non-monotonic torsion tests with different sample cross sections are analyzed. Second, for the identification of hardening parameters of steel, three different tension–compression samples are considered. In both examples, various combinations of tests are checked for sensitivity to measurement errors identifying best and worst combinations.

Background. Growing of both thin and thick epitaxial layers is an essential part of semiconductor device technology. Liquid phase epitaxy is among well-known technological methods. There are pulse methods of liquid phase epitaxy specially developed for obtaining thin epitaxial layers. Their adaptation or modification for obtaining thick epitaxial layers is an actual issue. Objective. This work deals with the possibility of obtaining of thick epitaxial layers by extending the capabilities of scanning liquid phase epitaxy technique which also relates to pulse liquid phase growing methods. Methods. In this work we considered the influence of extra heating of the substrate on the growth of epitaxial layers when using scanning liquid phase epitaxy technique. For this purpose we carried out modelling of heat- and mass transport processes in the apparatus of scanning liquid phase epitaxy in conditions of extra heating of the substrate. To experimentally approve the validity of the model proposed we carried out the growing of Ge epitaxial layer on GaAs substrate in the above mentioned conditions. Results. The modelling showed that if the substrate was in contact with the solution-melt more than 1 second in conditions of substrate extra heating in scanning liquid phase epitaxy method, a segment of epitaxial layer dissolution appeared in plots of the grown epitaxial layer thickness against the growth time. The crystallization front temperature was lower than the initial solution-melt temperature in this case. We showed that it was connected with the magnitude of initial cooling/heating of the substrate heater. The modelling also showed that the epitaxial layer growth occurred in kind of a temperature gradient due to the extra substrate heating. Thus in a few seconds there took place the growth in the time-constant temperature gradient. Using the extra substrate heating we obtained epitaxial Ge layer on GaAs substrate from Ga-Ge solution-melt. The growth time was 60 sec. The layer thickness determined by spherical slice technique was 12.6 um. Conclusions. In this work we showed that using extra heating of the substrate’s back side there appeared the conditions for growing of thick epitaxial layers by scanning liquid phase epitaxy technique in case when the substrate temperature was lower than the solution-melt temperature. Here the growth of thick epitaxial layers took place in the condition of temperature gradient at crystallization front.

A procedure has been developed and optimized for the synthesis of 3-{[4-methyl-3-(4-methylpiperazin-1-yl)]pent-1-en-1-yl}-4H-chromen-4-ones (as dihydrochlorides) by an unusual version of the Morita–Baylis–Hillman reaction. A number of the title compounds with various substituents in the chromene fragment and their deamination products have been synthesized, and their inhibitory activity against butyrylcholinesterase has been studied.

The effect of electronic properties of substituents in the reactants on the [4+2]-cycloaddition of 3-vinyl-chromen-4-ones (dienes) and N-vinylpyrrolidines (dienophiles) has been studied. The conditions determining the formation of 4,4a-dihydroxanthones or benzophenones as the major products have been found. The aromatization of 4,4a-dihydroxanthones via pyran ring opening has been interpreted by quantum chemical calculations. A wide series of new 4,4a-dihydroxanthone and benzophenone derivatives have been isolated.

The layer-by-layer growth of Ammann-Beenker graph (a quasi-periodic graph with eightfold symmetry) has been experimentally and theoretically studied. The limiting form for the growth of Ammann-Beenker graph is established in the form of a regular octagon, whose vertices are found explicitly. The lower and upper bounds of this form, which coincide with the growth form, are proven rigorously.

We report an easy and powerful approach to the synthesis of novel chromeno[4,3-d]pyrimidine-5-acetic acids through ANRORC reaction of electron-deficient 3-vinylchromones and 1,3-N,N-binucleophiles. The reaction proceeds under mild conditions (EtOH, rt) and is applicable to a wide range of substrates. The described compounds show fluorescence in the violet-blue range (390–460 nm) with Stokes shift of 40–80 nm and moderate quantum yield (0.15–0.20). As the electron-withdrawing group is conserved in the form of an acetic acid fragment, these compounds may readily be functionalized or conjugated to a required substrate for (bio)analytical purposes.

Long (~1 mm), narrow (30−40 μm in diameter) corrugated capillary-like channels were produced in the axially symmetric 2D interaction regime of 100 ns KrF laser pulses with polymethylmethacrylate (PMMA) at intensities of up to 5 × 1012 W/cm2. The channels extended from the top of a deep (~1 mm) conical ablative crater and terminated in a 0.5 mm size crown-like pattern. The modeling experiments with preliminary drilled capillaries in PMMA targets and Monte Carlo simulations evidenced that the crown origin might be caused by high-energy (0.1–0.25 MeV) electrons, which are much higher than the electron temperature of the plasma corona ~100 eV. This indicates the presence of an unusual direct electron acceleration regime. Firstly, fast electrons are generated due to laser plasma instabilities favored by a long-length interaction of a narrow-band radiation with plasma in the crater. Then, the electrons are accelerated by an axial component of the electrical field in a plasma-filled corrugated capillary waveguide enhanced by radiation self-focusing and specular reflection at the radial plasma gradient, while channel ripples serve the slowing down of the electromagnetic wave in the phase with electrons.

The influence of epoxy active diluents, 1,4-butanediol diglycidyl ether (BD) and furfuryl glycidyl ether (FUR), in the mixtures with benzoxazine monomer based on bisphenol A, formaldehyde and m-toluidine (BA-mt), on the properties of a matrix was disclosed in this work. Resins were modified to achieve good tackiness at room temperature and reduced viscosity. The influence of mono- and difunctional modifiers on the process of curing was studied by way of differential scanning calorimetry and oscillatory rheology. The addition of BD and FUR shifted the curing peak to higher temperatures and significantly reduced viscosity. Preferable tackiness at ambient temperature was achieved with 10 phr of epoxy components in mixtures. However, cured blends with difunctional epoxy BD had an advantage over monofunctional FUR in enhanced tensile strength with remaining glass transition temperature at the level of neat benzoxazine (217 °C).