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The objective of the study : to compare changes in the blood level of C-reactive protein (CRP) during the administration of different formulations of tocilizumab (TCZ) in COVID-19 patients admitted to hospital in real clinical practice. Subjects and methods . The cohort of 14 patients was included in the retrospective study; they all had a severe course of COVID-19 and were admitted to hospital: 7 patients received had intravenous infusions of tocilizumab and 7 had subcutaneous injections. The indication for tocilizumab prescription was the elevation of CRP blood level by 5 times and more or 2-fold and more elevation of ferritin above the norm. In the group receiving subcutaneous injections with tocilizumab, the proportion of elderly people was bigger and CRP levels were higher versus the group receiving intravenous infusions. The efficacy was assessed by changes in CRP levels on the 1st, 3rd and 7th day after the administration. The study included only the patients discharged from hospital with improvement of their state. Results. It has been demonstrated that when the patients develop cytokine storm, the use of both formulations of tocilizumab (for intravenous and subcutaneous administration) is effective. When tocilizumab was administered intravenously, the changes in CRP levels (especially at high rates - more than 150 mg/l) were more intense versus subcutaneous administration. The use of these formulations of tocilizumab had the same long-term efficacy: the level of CRP by the 7th day after administration decreased comparably in both groups, the time of complete normalization of this rate did not differ significantly. The different dynamics of CRP level decrease in each specific case could be associated both with the formulation of the drug and other factors that could not be established.

Approaches to the technology developed by OKBM Afrikantov for creating a supercomputer twin of a nuclear power plant on the basis of a three-level model are described. A software implementation of this technology based on homegrown software is proposed. Experience in using the technology is shown for the Yasen-M project, RITM-200, and BN-800.

Noble transition metal dichalcogenides (TMDCs) such as PtS2 and PtSe2 show significant potential in a wide range of optoelectronic and photonic applications. Noble TMDCs, unlike standard TMDCs such as MoS2 and WS2, operate in the ultrawide spectral range from ultraviolet to mid-infrared wavelengths; however, their properties remain largely unexplored. Here, we measured the broadband (245–3300 nm) optical constants of ultrathin PtS2 and PtSe2 films to eliminate this gap and provide a foundation for optoelectronic device simulation. We discovered their broadband absorption and high refractive index both theoretically and experimentally. Based on first-principle calculations, we also predicted their giant out-of-plane optical anisotropy for monocrystals. As a practical illustration of the obtained optical properties, we demonstrated surface plasmon resonance biosensors with PtS2 or PtSe2 functional layers, which dramatically improves sensor sensitivity by 60 and 30%, respectively.

Atomically thin transition metal dichalcogenides (TMDCs) present a promising platform for numerous photonic applications due to excitonic spectral features, possibility to tune their constants by external gating, doping, or light, and mechanical stability. Utilization of such materials for sensing or optical modulation purposes would require a clever optical design, as by itself the 2D materials can offer only a small optical phase delay – consequence of the atomic thickness. To address this issue, we combine films of 2D semiconductors which exhibit excitonic lines with the Fabry-Perot resonators of the standard commercial SiO2/Si substrate, in order to realize topological phase singularities in reflection. Around these singularities, reflection spectra demonstrate rapid phase changes while the structure behaves as a perfect absorber. Furthermore, we demonstrate that such topological phase singularities are ubiquitous for the entire class of atomically thin TMDCs and other high-refractive-index materials, making it a powerful tool for phase engineering in flat optics. As a practical demonstration, we employ PdSe2 topological phase singularities for a refractive index sensor and demonstrate its superior phase sensitivity compared to typical surface plasmon resonance sensors.

The article describes the main achievements in the study of ulcerative colitis (UC) - a disease known since ancient times. «Bloody» non-epidemic diarrhea was described by Hippocrates. The first detailed description was made by K. Rokitansky in 1842. In 1875, S. Wilks and W. Mason first studied the pathomorphology of the colon in UC. The term «non-specific ulcerative colitis» was proposed by the Russian surgeon A. S. Kazachenko in 1913 at the 13th Congress of Russian surgeons. The historical excursion presents the main stages and achievements of surgical treatment of UC.

AIM: to evaluate the efficacy, safety and drug tolerance of «Colokit» for bowel cleansing before colonoscopy.PATIENTS AND METHODS: an open prospective non-randomised study of the quality of bowel cleansing was carried out in 30 patients (17 females, aged 26-72 years), who underwent diagnostic colonoscopy after using «Сolokit» (Mayoly Spindler, France) using two different regimes (recommended and alternative).RESULTS: the quality of the bowel cleansing was significantly better in patients after «Colokit» use in recommended regime vs alternative regime. No difference in subjective assessment of patients’ comfort during bowel preparation was found in both regimes. CONCLUSION: the «Colokit» agent provides good preparation and patients’ comfort and can be recommended for the bowel cleansing before colonoscopy.

Hydrogen sensors were fabricated with a well-known structure, formed by depositing WOx films (with or without an additional Pt overlayer) onto SiC substrates. These sensors differed in terms of the morphology and nanostructure of the WOx films, which were pulsed laser deposited (PLD) under varying conditions. The sensory characteristics of WOx/SiC and Pt/WOx/SiC samples were analyzed using conventional current–voltage measurements. In addition, the possibility of detecting an electrical signal in these structures without applying an external voltage (EMF-powered mode) was investigated. The sensor response strongly depended on the qualities of the metal oxide film, including its strength, uniformity, continuity, and adhesion to the SiC substrate. Optimization of the PLD allowed the formation of triclinic WOx 27 times. The highest voltage detected for an external load of 1 kΩ was ~400 μV. The Pt film deposition markedly worsened the sensory properties of Pt/WOx/SiC structures measured by the EMF-powered mode. Possible mechanisms of the appearance of the EMF in the prepared structures are considered.

Graphene is a promising building block material for developing novel photonic and optoelectronic devices. Here, we report a comprehensive experimental study of chemical-vapor deposited (CVD) monolayer graphene’s optical properties on three different substrates for ultraviolet, visible, and near-infrared spectral ranges (from 240 to 1000 nm). Importantly, our ellipsometric measurements are free from the assumptions of additional nanometer-thick layers of water or other media. This issue is critical for practical applications since otherwise, these additional layers must be included in the design models of various graphene photonic, plasmonic, and optoelectronic devices. We observe a slight difference (not exceeding 5%) in the optical constants of graphene on different substrates. Further, the optical constants reported here are very close to those of graphite, which hints on their applicability to multilayer graphene structures. This work provides reliable data on monolayer graphene’s optical properties, which should be useful for modeling and designing photonic devices with graphene.

We studied the possibility of using pulsed laser deposition (PLD) for the formation of a MoSx/WSe2 heterostructure on a dielectric substrate. The heterostructure can be employed for effective solar water splitting to produce hydrogen. The sapphire substrate with the conducting C(B) film (rear contact) helped increase the formation temperature of the WSe2 film to obtain the film consisting of 2H-WSe2 near-perfect nanocrystals. The WSe2 film was obtained by off-axis PLD in Ar gas. The laser plume from a WSe2 target was directed along the substrate surface. The preferential scattering of selenium on Ar molecules contributed to the effective saturation of the WSe2 film with chalcogen. Nano-structural WSe2 film were coated by reactive PLD with a nanofilm of catalytically active amorphous MoSx~4. It was established that the mutual arrangement of energy bands in the WSe2 and MoSx~4 films facilitated the separation of electrons and holes at the interface and electrons moved to the catalytically active MoSx~4. The current density during light-assisted hydrogen evolution was above ~3 mA/cm2 (at zero potential), whilst the onset potential reached 400 mV under irradiation with an intensity of 100 mW/cm2 in an acidic solution. Factors that may affect the HER performance of MoSx~4/WSe2/C(В) structure are discussed.

Aim: to estimate the quality and availability of medical care for patients with ulcerative colitis (UC) and Crohn’s disease (CD), to assess the impact of the economic burden of these diseases on the healthcare budget of Russia and to systematize the main problems in the organization of medical care and drug supply for patients with inflammatory bowel diseases (IBD).Regional IBD databases (2016-2018), official statistical databases, costs of treatment and results of expert interviews with specialists in IBD were used in the study.The analyzed databases showed 104,668 patients with UC in Russia in 2018 (prevalence rate 71 per 100,000 people) and 66,647 patients with CD (prevalence rate of 45 per 100,000 people). The economic burden including agents for biologic therapy (ABT) for the UC was 39.54 billion rubles a year (495 rubles per capita), and CD - 32.98 billion rubles a year (378 rubles per capita). It requires an additional 9.87 billion rubles annually for UC and 9.20 billion rubles annually for CD patients to provide the complete supply with ABT.The annual burden of IBD is 72.52 billion rubles, which is comparable to the costs of other socially significant diseases, including malignant tumors. It shows the high social and economic value of IBD for the country. The main problems of medical care and drug supply for IBD patients are the mismatch of official statistical data and real IBD prevalence in Russia due to absence of comprehensive register and the insufficient supply with ABT due to limited funding. A federal center for IBD should be founded for better quality of registration, for the precise monitoring and for the active management of personal drug supply.

Laser-initiated modification of the structure and morphology of the MoS2 and MoSe2 targets used to obtain antifriction thin-film coatings by pulsed laser deposition were studied. Significant differences were revealed in the ablation mechanism of these materials that caused important differences in the structure formation of MoS x /Mo and MoSe x /Mo coatings containing submicro- and nano-scaled Mo particles. Results of the study of structure, morphology and tribological properties of these coatings (coefficient of friction, wear resistance) when testing by the technique of sliding the ball over the covered disk under different air humidity and temperatures are presented. Comparative studies have revealed the superiority of the MoSe x /Mo coatings over the MoS x /Mo coatings during sliding friction under varying conditions of applications in frictional unites.

The results of structural and electrochemical studies of thin Mo-S-P films obtained by pulsed laser deposition at various conditions from a target made of mixture of MoS2 and P powders are presented. For variation of S/P ratio and modification structure of the catalytic films, the deposition of the laser plume was conducted in vacuum, in Ar and H2S gas. The highest electrocatalytic properties for activating the hydrogen evolution reaction in an acid solution were found for composite amorphous/nanocrystalline MoS6P/nc-Mo films. In the chemical stateof S 2p, the high binding energy dominated. The doping of the films with phosphorus increased the efficiency of the reaction compared with that of MoS x /nc-Mo films. The analysis of the synergistic effect of phosphorus on the performance of amorphous MoS x P y films in H2 evolution was carried out using the density functional theory.

Turbulent Rayleigh–Benard convection in cubic cells is studied experimentally using two similar but not identical experimental setups in different laboratories. Both teams have made experiments for the same set of Prandtl and Rayleigh numbers (Pr = 3.5, Pr = 6.1, Ra = 2.0 · 10 9 , Ra = 6.0 · 10 9 , Ra = 1.6 · 10 10 ). Experiments showed that the structure of the mean flow and local characteristics of turbulent pulsations are robust and do not depend strongly on the technical details of experimental setup. Periodic low-frequency oscillations and orientations of large-scale circulation (LSC) are more sensitive to the experimental setup design. Long-time measurements using differential thermocouples revealed that preferential orientation of LSC is along of one of the diagonals, however it can deviate from exact diagonal orientation. Analyses of temperature and velocity measurements showed that dominant periodic oscillations of LSC can not be explained as simple modulation of the intensity of the large-scale diagonal flow because most intense oscillations are observed in the direction, which is orthogonal to the plane of LSC. Experimental data obtained independently by two teams can be used as a benchmark for CFD codes. Numerical simulation using a standard widely-spread CFD code was carried out. In general, on the base of overall comparison between experimental and large-eddy simulation results we concluded that for the described regimes LES gives satisfactory agreement with experiment reproducing the small-scale dynamics of the turbulent flow and the behavior of LSC.

We demonstrate the possibility of fabricating high-efficiency semiconductor hydrogen detectors based on tangsten-oxide thin films deposited onto silicon-carbide crystals by reactive pulsed-laser deposition. The obtained WO3/SiC structures ensure a noticeable voltage shift ΔU on the reverse branch of the I−V characteristics without commonly used catalyst layers of platinum-group metals. The ΔU value reached 2.1 V at a detected hydrogen concentration of 0.2% in air at 350°C. The response times to hydrogen inlet and recovery of the WO3/SiC structure after hydrogen outlet are found to be much shorter than those for the Pt/WO3/SiC structure. The high performances of the fabricated WO3/SiC sensor are due to the layered structure of the orthorhombic phase of tungsten oxide, which consists of loosely packed microcrystalline plates containing nanocrystals smaller than 100 nm.

It has been shown that, at elevated temperatures (∼350°C), the most distinct response to H2 from the thin film structure Pt/WO x /SiC is achieved at registration of change in voltage for the reverse branch of a current-voltage characteristic. Comparative studies of electric current conduction through the structure and over its surface (with deposited Pt film) have led to the conclusion that a change in properties of the Pt/WO x and WO x /SiC interfaces under action of H2 mostly determines efficiency of response of the structure in the case of “transverse” measuring geometry. In the case of a 2% concentration of H2 in air the voltage shift for the reverse branch at a current of ∼10 μA reached 5 V against 2 V on the forward branch and “planar” geometry of measurements.

The results of simulation and measured parameters of a dual-selective static random access memory cell with two address inputs implemented in 180-nm CMOS technology are presented. Dependences of the static noise margin (SNM), write margin (WRM), noise margin at separate control nodes, and digit current on the potential of the trigger common bus are investigated. An increase in the SNM by 26% (up to 222 mV) and in the WRM by 6% (up to 1017 mV) as compared to the known circuit is obtained.

We have studied the possibility of controlling important structural characteristics of WSex films, which belong to the class of layered materials and have good prospects for application in modern nano- and optoelectronic devices. It is established that, by using thermal treatment and ion irradiation during pulsed laser deposition (PLD) in the shadow of an antidroplet shield, it is possible to vary the Se/W atomic ratio from 5 to 1.5, change the character of atomic packing, and obtain films with either smooth or rough surfaces. An increase in the height of parabolic protrusions on the surface up to 200–500 nm leads to a decrease in the optical reflection coefficient in a broad wavelength range from 30% (typical of smooth films) to 6%, which can favor a significant increase in the efficiency of solar cells based on semiconductor films of this type.

The results of a comparative study of the electrical properties of gas-sensitive semiconductor structures grown by the pulsed laser deposition of platinum, platinum ion implantation, and a combined method of platinum implantation and deposition onto an n-6H-SiC substrate are presented. Double-layer structures show a stronger response to hydrogen gas with a more pronounced diode behavior of the currentvoltage characteristics at high temperatures of ∼500°C than single-layer ion-implanted structures. Furthermore, double-layer structures exhibit higher reproducibility of the current-voltage characteristic parameters during thermal cycling in a hydrogen-containing medium than ordinary thin-film structures on SiC substrates. The chemical state of ion-implanted platinum and the structure of thin-film layers after long-term testing are studied under harsh conditions. Possible mechanisms of the effect of platinum on the current flow in the ion-implanted layer and its dependence on the composition of the surrounding gaseous medium are considered.

Thin-film precursors of BC x were formed by pulsed laser codeposition of boron and carbon. Targets made of pressed boron and carbon powders with an equal element content (B/C = 1/1) and an increased carbon content (B/C = 1/3) were used. The films were deposited on sapphire substrates at elevated temperature (700°C) which determined the initial properties of the precursor BC x films. Irradiation of the films was carried out by laser pulses of nanosecond duration with varying intensity. The films obtained by laser annealing of BC x (Q-BC x ) were studied by scanning electron microscopy and micro-Raman spectroscopy. Irradiation under optimal conditions made allowed to realize pulsed melting of the films and partial preservation of their continuity on the substrate. The local structure of Q-BC x films and the nature of the changes in their electrophysical properties depended on the composition of the precursor films and the laser irradiation regimes.

A comparative analysis of the abilities of several novel methods to produce ultrathin molybdenum disulphide (MoS2) films containing from 1 to 10 molecular layers was carried out. To deposit MoSxfilms and MoOxprecursor films, the atomic flux was formed by laser ablation of Mo, MoS2, and MoO3targets. Saturation with sulphur of the deposited layers was performed using a reactive gas (hydrogen sulphide) or by thermally activated treatment of thin-film precursors in a sulphur vapor. It has been established that the use of hydrogen sulphide makes it possible to obtain ultrathin MoS2films at relatively low temperatures ∼ 350 °C. However, these films contained local defects which were absent in the films prepared by the treatment of thin film MoOxprecursors in sulphur vapours at higher temperatures (≥ 650°C).

The effect of the conditions of pulse laser deposition of MoSe x thin-film coatings on the structural and phase state of surface layer on an iron substrate and on the distribution of elements over the thickness of the coatingsubstrate interface is investigated. Model multilayer test pieces bearing a thin film of 57Fe are studied. The speed distributions of single- and double-charge ions due to pulse laser irradiation of a MoSe2 target are measured and used for mathematical modeling of the motion of laser plasma to the surface of the substrate in a pulse electric field. The energy distributions of the incident ions are computed as a function of the time of the action of the high-voltage pulse following the laser pulse and used to explain the experimentally determined effects.

Experimental data and results of mathematical modeling have been used to determine the energy characteristics of an ion beam used to assist pulsed laser deposition (PLD) of MoSe2 layers under conditions of positive high-voltage pulses applied to a laser-ablated target. It is shown that PLD assisted by implantation of ions at energies up to 100 keV can be used to obtain MoSe2 coatings on 57Fe-containing substrates. Analysis of the concentration-depth profiles of Mo, Se, and 57Fe atoms and the phase composition of a near-surface layer in samples shows evidence for mass transfer domination in thermal spikes and a significant influence of ion impact on the structure of this layer at the nanoscale. These features are manifested by the formation of a nanocomposite structure with inclusions of a specific hexagonal FeSe phase. The obtained results demonstrate the existence of principally new possibilities of using the proposed modified PLD method for controlled formation of solid lubricant coatings with improved properties.

Diode structures with ideality factors of 1.28-2.14 and potential barriers from 0.58 to 0.62 eV on the semiconductor side were formed by pulsed laser deposition of Au, Ag, Cu, Pd, Pt, W, and Zr metal films on n-6H-SiC crystal without epitaxial layer preparation. A high density of surface acceptor and donor states was formed at the metal-semiconductor interface during deposition of the laser-induced atomic flux, which violated the correlation between the potential barrier height and metal work function. The barrier heights determined from characteristic currents and capacitance measurements were in quite good agreement. For the used low-resistance semiconductor and contact elements, the sizes of majority carrier (electron) depletion regions were determined as 26-60 nm.

Peculiarities of WO x films fabrication by reactive pulsed laser deposition for high temperature Pt-oxide-SiC devices formation were investigated. Deposition of the oxide film was also carried out in such a way as to prevent deposition of droplet fraction (deposition with anti-droplet screen). Direct Simulation Monte Carlo and Kinetic Monte Carlo methods were performed for the deposition processes modeling. The response of the SiC-based devices to hydrogen-containing gases depends on the conditions of deposition of the oxide layer. The best properties were found in the sensor obtained by depositing the scattered flux of W atoms in a shady area on SiC substrate at an oxygen pressure of 10 Pa.

Physical, chemical and tribological properties of the MoSex and MoSe x C y coatings for micromechanical applications grown by pulsed laser deposition in vacuum and in a rarefied inert gas (argon) atmosphere are studied. In a number of experiments a disk-shaped screen was used that is placed on the path of the expansion of laser plume in order to trap the droplet fraction. Upon deposition in a gas at a pressure of ~2 Pa, stoichiometric MoSe 2 coatings with improved antifriction properties as compared vacuum-deposited MoSe x (x