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Highlights. It is the first pseudorandomized comparative study of xenopericardial frame and half-frame bioprostheses treated with diepoxin in the aortic position use and its direct results.Aim. A comparative assessment using the Propensity Score Matching method of the in-hospital clinical and hemodynamic results of the semi-framed epoxy-treated xenopericardial prosthesis “T-ara” and the framed epoxy-treated xenopericardial prosthesis “UniLine” (“NeoKor”, Kemerovo, Russia) for isolated aortic valve replacement implantation.Methods. 33 recipients of the “UniLine” prosthesis were selected by Propensity Score Matching method in a ratio of 1:1 to 33 observations from the “T-ara” group according to the compliance criteria: gender, age, body surface area, end-diastolic volume of the left ventricle (LV) and the pre-operative presence/absence of the aortic regurgitation.Results. Hospital mortality in the “T-ara” and “UniLine” groups was 3.03 (n = 1) and 6.06% (n = 2), respectively, p = 0.920. Non-fatal complications in the “T-ara” and “UniLine” groups was 7 (21.2%) and 18 (54.6%), p = 0.163. The incidence of postoperative heart failure and arrhythmias was higher in “UniLine” recipients (p = 0.001). The average stay in the intensive care unit was longer in the “UniLine” group than in the “T-ara” group, p = 0.05. Postoperative end-systolic and end-diastolic dimensions and volumes (and the corresponding indexes) of the LV, as well as the myocardial mass and its index in both groups had no statistically significant changes in relation to preoperative data. The comparative assessment of left ventricular remodeling parameters depending on the prosthetic size revealed no significant differences. The average pressure gradient in the “T-ara» and “UniLine” group of size 21mm was 12.2±7.4 and 12.2±5.0 mm Hg. (p>0.050). The average pressure gradient in the group “T-ara” and “UniLine” size 23–25 mm was 10.2±4.1 and 9.9±0.3 mm Hg, p>0.050. The regression degree of LV myocardial mass index in the groups did not have significant differences.Conclusion. At the hospital stage, the semi-framed epoxy-treated biological prosthesis “T-ara” has a similar clinical and hemodynamic profile with the framed biological prosthesis “UniLine”. The frequency of postoperative heart failure and cardiac arrhythmias is statistically significantly higher in the “UniLine” group (framed bioprostheses).

Cough is a frequent manifestation of COVID-19 (COronaVIrus Disease 2019), therefore, it has an important diagnostic value. There is little information about the characteristics of cough of COVID-19 patients in the literature. To perform a spectral analysis of cough sounds in COVID-19 patients in comparison with induced cough of healthy individuals. Methods. The main group consisted of 218 COVID-19 patients (48.56% – men, 51.44% – women, average age 40.2 (32.4; 50.1) years). The comparison group consisted of 60 healthy individuals (50.0% men, 50.0% women, average age 41.7 (31.2; 53.0) years) who were induced to cough. Each subject had a cough sound recorded, followed by digital processing using a fast Fourier transform algorithm. The temporal-frequency parameters of cough sounds were evaluated: duration (ms), the ratio of the energy of low and medium frequencies (60 – 600 Hz) to the energy of high frequencies (600 – 6 000 Hz), the frequency of the maximum sound energy (Hz). These parameters were determined in relation to both the entire cough and individual phases of the cough sound. Results. Significant differences were found between some cough parameters in the main group and in the comparison group. The total duration of the coughing act was significantly shorter in patients with COVID-19, in contrast to the induced cough of healthy individuals (T = 342.5 (277.0; 394.0) – in the main group; T (c) = 400.5 (359.0; 457.0) – in the comparison group; p = 0.0000). In addition, it was found that the cough sounds of COVID-19 patients are dominated by the energy of higher frequencies as compared to the healthy controls (Q = 0.3095 (0.223; 0.454) – in the main group; Q (c) = 0.4535 (0.3725; 0.619) – in the comparison group; p = 0.0000). The maximum frequency of cough sound energy in the main group was significantly higher than in the comparison group (Fmax = 463.0 (274.0; 761.0) – in the main group; Fmax = 347 (253.0; 488.0) – in the comparison group; p = 0.0013). At the same time, there were no differences between the frequencies of the maximum energy of cough sound of the individual phases of cough act and the duration of the first phase. Conclusion. The cough of patients with COVID-19 is characterized by a shorter duration and a predominance of high-frequency energy compared to the induced cough of healthy individuals.

Objective: to analyze the results of treatment in patients with refractory glaucoma of various stages of the disease by microimpulse cyclophotocoagulation.Patients and methods. We examined 43 patients aged 68.5 ± 13.2 years with primary open-angle repeatedly operated subcompensated glaucoma (POAG) of advanced (13) and advanced (30) stages before and after performing MCPC (SUPRA 810 device, QuantelMedical, France) using standard laser parameters: energy W = 2000 MJ, 31.3 % — duty cycle, exposure time — 80 seconds per hemisphere.Results. The operation and postoperative period were uneventful. The hypotensive effect was achieved in all cases up to 6 months of follow-up. In the advanced stage of the disease, IOP decreased from 26.8 ± 7.8 mm Hg to an average of 17.1 ± 8.1 mm Hg (p < 0.05), and the amount of antihypertensive agents decreased from 2.89 ± 0.74 to 2.4 ± 0.6. in patients with advanced stage, IOP decreased from 29.9 ± 7.8 mm Hg to 21.0 ± 8.3 mm Hg (p < 0.05), and the amount of antihypertensive agents decreased from 3.1 ± 0.4 to 2.8 ± 0.5. The maximum corrected visual acuity (MCI) in all patients remained at the preoperative level during the entire follow-up period.Conclusion. Analysis of the results has shown that the use of microcyclophotocoagulation in patients with refractory glaucoma has not led to the development of postoperative complications, reduced intraocular pressure by 36.2 % from baseline, when developed and 29.8 % in advanced stages of the disease, reduced the number of antihypertensive drugs was 17 % in the second and 10 % at third stage and have not led to a decrease in visual function at 6 months follow-up. Thus, it is proved that the use of a diode laser in micro-pulse mode during microcyclophotocoagulation is a safe and effective method of treating refractory forms of glaucoma at various stages of the disease.

Semiconductor lasers have developed rapidly with the steady growth of the global laser market. The use of semiconductor laser diodes is currently considered to be the most advanced option for achieving the optimal combination of efficiency, energy consumption, and cost parameters of high-power solid-state and fiber lasers. In this work, an approach for optical mode engineering in planar waveguides is investigated. The approach referred to as Coupled Large Optical Cavity (CLOC) is based on the resonant optical coupling between waveguides and allows the selection of high-order modes. The state-of-art of the CLOC operation is reviewed and discussed. We apply the CLOC concept in our waveguide design strategy. The results in both numerical simulation and experiment show that the CLOC approach can be considered a simple and cost-efficient solution for improving diode laser performance.

Vlasov–Fokker–Planck simulation codes occupy an important niche in modeling laser-produced plasmas, since they are well suited to studying the effect of collisions on electron kinetic phenomena, especially energy transport. One of the most important elements of energy transport is the absorption of laser light by the plasma; however, simulating this in detail requires resolving oscillations of the laser light, whose characteristic timescale is orders of magnitude shorter than the simulation time needed to study transport physics. For this reason, most Vlasov–Fokker–Planck codes used to study electron transport in laser plasmas rely on simplified models of the laser–plasma coupling. Their underlying assumptions nominally preclude their use for modeling laser light having short-scale structure in space or time, such as broadband lasers. In this work, we derive a more general computational framework suitable for arbitrarily structured laser fields. Our approach is based on an extended set of Vlasov–Fokker–Planck equations that separately solve for the low- and high-frequency plasma response. We implement these extended Vlasov–Fokker–Planck equations in the spherical harmonic code K2 and demonstrate the performance of the method on several laser absorption test problems, with particular attention to the judicious selection of time steps, time integrators, and spherical harmonic truncation, according to the intensity and spectrum of the laser light under consideration. Comparison with the widely used Langdon absorption operator shows the Langdon operator performs remarkably well for predicting laser heating in the simple cases considered here, even in situations that would seem to violate its underlying assumptions.

In the present study, a series of K-modified CoMoS catalysts with compositions of 10% K, 3.6% Co, and 12 wt % Mo supported over novel commercial activated carbons such as powder materials (DAC and OBC-1) and fiber materials (fabric active sorption (TCA) and nonwoven activated material (AHM)) were prepared and characterized by Brunauer-Emmett-Teller (BET), X-ray fluorescence (XRF), scanning electron microscopy (SEM), SEM-energy dispersive X-ray (EDX), and transmission electron microscopy (TEM). The catalytic activities for higher alcohol synthesis from syngas, conducted at

Result of the government's many years of efforts to liberalize the market of social services is a huge number of organizations that are privately owned — 45,9%, but which have minimal impact on the infrastructure development. The reason is that private business alienates long-term and capital-intensive projects, and the overwhelming part of the social infrastructure (for sports facilities it constitutes 95.2%) remains in the state and municipal ownership. The state mistakenly classifies concession projects as investment projects that are paid back only through fee-based exploitation. Thus, social policy is being deprived of a promising mechanism — transformation of concession agreements into the basis for socialization of private investments, infrastructure and services. The identified problems of social disorientation in specifying criteria for evaluating the proposals of participants in concession tenders form the basis for asocial conditions of concession agreements, which makes social services inaccessible to the general population. Commercialization of the activities of social facilities is admissible (although in a limited sense), but at the same time, services at state tariffs or free of charge should prevail. There is a need for systematic scientific and methodological work on cross-cutting incorporation of this approach into the current regulatory framework and guidelines in order to create a network of basic social infrastructure for all segments of the population.

A new method for the electrodeposition of copper on oxidized aluminum alloys to form electrolytic coatings exhibiting high performance properties has been discussed. The effect of an azo compound—methyl red (MR)—additive on the structure and physicomechanical properties of the copper coatings formed on oxidized aluminum has been studied. Samples of aluminum alloys AD1M and AMg6BM have been subjected to an anodic treatment under identical conditions in two oxidation electrolytes of different compositions. Copper has been electrodeposited on oxidized aluminum alloy samples using a standard copper plating electrolyte. Comparison with a copper plating electrolyte of an identical composition with an MR azo dye additive has been conducted. The microstructure and adhesive properties of the copper coating formed on oxidized aluminum alloys have been studied. The relationship between the physicomechanical properties of the copper coating (microhardness, open porosity, adhesion) and the action of an azo dye additive in the copper plating electrolyte has been studied. The use of this technology will make it possible not only to increase the reliability and durability of machine parts and mechanisms but also to restore old parts and mechanisms.

The effect of supercell size in the ribbon model of molybdenum disulfide edge on the cell electronic structure and specific energy was investigated, with and without spin polarization. The differences found were discussed in terms of electron count. Diagnostic criteria for the model applicability and the effect of opposite edge were discussed.

The mechanisms of the physiological and therapeutic effects of broadband modulation currents, the peculiarities of their impact on the main functional and regulatory systems of the human body, as well as therapeutic techniques, indications and contraindications for therapeutic use, the fundamentals of physics and biophysics of medium-frequency electrical exposure have been studied. The technique and methods of carrying out medical procedures using the modern domestic apparatus "Nadezhda" for treatment with broadband modulation currents are presented.

Introduction. The problem of preventing the development of stroke in workers under the influence of harmful production factors is urgent. The aim of the study was to study the characteristics of stroke in men under conditions of industrial noise exposure, to establish the prognostic value in the formation and course of the disease. Material and methods. The study involved 71 men with stroke from 30 to 65 years old, who worked in conditions of industrial noise in the professions of "pilot of civil aviation aircraft" and "adjuster of railway construction machines" for 5 years or more. In order to develop a mathematical model for predicting the development of stroke and to establish an individual risk, a group of 81 men from 30 to 65 years old, working under conditions of exposure to occupational noise for 5 years or more, who had no history of stroke data, were also examined. Using the method of sequential inclusion of the studied risk factors (Forward Stepwise), we selected those that made an independent significant contribution to the development of stroke. Based on the results obtained, a logistic regression formula was created, which determines the likelihood of stroke in men working under conditions of occupational noise. Results. In the group of patients with stroke, persons of middle age were found significantly more often - 53.5%. Ischemic stroke prevailed among clinical forms - 90.1%. Among the risk factors prevailed: arterial hypertension (AH) in 100.0% of cases, dyslipidemia factor in 78.9%, smoking factor in 59.1%. A direct moderate correlation was found between the level of systolic blood pressure, diastolic blood pressure and the index of the NIHSS 1 and NIHSS 2 scales. The influence of the following factors on the development of stroke was established: the level of total cholesterol (β-coefficient=1.0, p=0.001), the presence of atrial fibrillation factor (β-coefficient=2.9, p=0.004), the presence of a factor of alcohol abuse (β-coefficient=1.1, p=0.049), the patient has a diagnosis of grade 2 AH (β-coefficient=13, p=0.041) or a diagnosis of grade 3 hypertension (β-coefficient=1.8, p=0.008). A p(X) value exceeding 0.5 indicates a high risk of developing a stroke. The sensitivity of the proposed method was 76.1%, specificity - 74.1%. Conclusion. The proposed multivariate model is informative for the individual prediction of the development of stroke in men working in conditions of exposure to occupational noise, because reflects the degree of influence of one factor or another on the development of the disease.

The state's responsibility for development of social infrastructure has not been questioned by modern Russian and foreign economists for many years. An indicator of implementing the national goals of the Russian Federation development for the period up to 2030 is not only an increase in life expectancy up to 78 years, but also a half reduction in the poverty level compared to indicator of 2017 [1], which points out the need not only to ensure additional income for the elderly, but also to reduce their costs. In the context of limited budgetary opportunities, the state's social policy is focused on developing commercial sector of social services and the sector of socially oriented NPOs that are not interested in development of capital-intensive infrastructure component at social tariffs. Private stationary facilities are targeted at wealthy people and are inaccessible to most elderly people who have to turn to the gray services market. Excessive commercialization has embraced even state-owned infrastructures, created or reconstructed through the mechanism of public-private partnership. This results in limited availability of public good and competition for access to it.

Experiments have been conducted on the OMEGA EP laser facility to study the effect of density scale length and overlapping beam geometry on laser-plasma instabilities near and below the quarter-critical density. Experiments were conducted in both planar geometry (density scale length [Formula: see text] [Formula: see text] 190 to 300 [Formula: see text]m) and spherical geometry ([Formula: see text] [Formula: see text] 150 [Formula: see text]m) with up to four overlapping beams and were designed to have overlapped intensities and density scale lengths comparable to OMEGA spherical experiments, but with many fewer beams. In comparison with previous experiments on OMEGA and National Ignition Facility, it is confirmed that shorter density scale lengths favor the two-plasmon decay (TPD) instability, while longer density scale lengths favor stimulated Raman scattering (SRS). In addition, for experiments at the same scale length and overlapped laser intensity, higher single-beam intensities favor SRS, while a larger number of overlapping beams favor TPD.

Edge-emitting lasers with active regions based on novel InGaAs/GaAs quantum heterostructures of transitional dimensionality, i.e., quantum well-dots, which are intermediate in properties between quantum wells and quantum dots, are studied. It is shown that the rate of the lasing-wavelength blue shift decreases with increasing number of quantum well-dot layers in the active region and with increasing optical confinement factor as the cavity length decreases. In a laser with 10 quantum well-dot layers, the lasing-wavelength position remains within the limits of the fundamental optical transition down to the smallest cavity lengths (100 μm). In devices with a single quantum well-dot layer and/or with a low optical confinement factor, lasing directly switches from the ground state to waveguide states omitting excited states below ≤200 μm. Such an effect has not been observed in quantum-well- and quantum-dot lasers and can be attributed to the abnormally low density of excited states in quantum well-dots.

Analytical expressions are presented, and, through them, the analysis of component parts of the electrical resistance of injection microdisk lasers is carried out depending on the size of the microdisk resonator, parameters of the substrate, and configuration of the contact to it.

Russia’s ability to demonstrate own subjectness and become a world leader in the fight against COVID-19 can be viewed as a mobilization Russian civilization code. In the context of growing threats, it is necessary not to wait for this mobilization civilization code to work, but to form adequate mechanisms for proactively strengthening the subjectness of the country’s development and security. The basic technologies for destroying the subjectness of development and ensuring the security of Russia are considered. A system of ontologies is proposed that sets the basis for improving the mechanisms of public participation and public-private partnership in strengthening the subjectness of Russian development.