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The power conversion efficiency of the ternary PSCs (16.32%) is higher than that for binary counterparts, i.e., 13.16% and 12.62% for P(DTB-BDD):DBTBT-IC and P(DTB-BDD):Y6, respectively.

Resume. Acute cerebral circulatory disorders are characterised by various changes in brain cells, often leading to mass death. This review presents a list of markers associated with different types of cell death occurring in acute cerebral circulation disorders and identifies the importance of these markers in the diagnosis of haemorrhagic and ischaemic stroke. Acute cerebral circulation disorder is one of the most debated issues in modern resuscitation and medicine, as it is a severe condition leading to stroke and subsequent patient death, if not treated promptly. However, rapid treatment and diagnosis of stroke is difficult due to the lack of study of morphological signs and biomarkers to reliably determine the nature of the injury. An in-depth analysis and systematization of the available information on this topic is needed. Purpose of the review: to reveal the correspondence between the molecular mechanisms of cell death in acute disorders of cerebral circulation and their morphological manifestations. Material and Methods. A total of 50 most relevant sources of information were selected. The sources were selected from the databases of medical and biological publications PubMed, Scopus, Web of Science, RSCI, and fundamental works of scientific literature on the considered topic were involved. Results. The main mechanisms of cell death in stroke were identified and analyzed, the morphological and histological features of the observed processes and their structural manifestations were reviewed. Besides, the most frequently detected molecular markers specific for each type of cell death were listed. Conclusion. The study of molecular pathways and cellular reorganization processes characteristic of different types of cell death as well as their corresponding biological markers is of important diagnostic value in the detection of cerebral circulatory disorders. Determination of morphological and molecular markers typical for this condition will allow a prompt diagnosis of stroke and minimization of its negative consequences.

Aim to study the immunomodulator-induced individual cytokine production by peripheral blood mononuclear cells (PBMCs) and to evaluate the potential of using this approach as a universal cellular test system in personalized medicine. Material and methods. The peripheral blood mononuclear cells given by donors were cultured in vitro in the presence of immunomodulators Imunofan and Polyoxidonium. After incubation, the enzyme-linked immunosorbent assay (ELISA) of the culture medium for the presence of pro-inflammatory cytokines IL-6, IL-8/CXCL8, MCP-1/CCL2, and IFN- cytokines was performed. Results. The results of the experiment have demonstrated the absence of spontaneous or immunomodulator-induced production of IFN- by PBMCs. These data correspond to the information presented earlier in the scientific literature. We also observed a pronounced inhibitory effect of both immunomodulators on the production of cytokines MCP-1/CCL2, IL-6, IL-8/CXCL8 by PBMCs, along with the individual variability of their production and the cumulative effect of production over time. Conclusion. The features of the production of pro-inflammatory cytokines by PBMCs into the medium in the presence of immunomodulators, revealed by the in vitro screening, can be used to develop universal in vitro cellular test systems for personalized diagnosis of a number of socially significant inflammatory and autoimmune diseases.

A prospective comparative analysis, i.e. the results of treatment of 68 patients, was carried out. The focal form of chronic post-traumatic osteomyelitis of the distal third of the tibia was focused. All patients were subjected to surgical debridement of the osteomyelitic focus on the variant of osteonecrectomy, followed by myoplastic reconstruction of the formed bone defect with chopped autologous muscle. In 30 patients, the traditional method of myoplastic reconstruction was used, and in 38 patients, the improved one. We added autologous Platelet-Rich Plasma (hereinafter - PRP) to the muscle graft before placing it into the bone defect. After filling in the defect, we sutured a Resorbable Collagen Membrane (hereinafter - RCM) to its edges in order to seal the defect and additionally fix the muscle graft. The dynamics of changes in the structure and the rate of fixation of the muscle graft to the walls of the bone cavity, the duration of the local inflammatory response, the duration of hospitalization, short-term outcomes, and long-term results of treatment in the comparison groups were evaluated.

The article tells about the 60-year history of the creation of a set of basic lecture demonstrations at the Physical Department of the Novosibirsk State University and about the subdivision for demonstrations support – from the moment the university was founded. The evolution of a set of demonstration installations, methodological descriptions andtechniques for using equipment in the process of teaching physics in various situations is considered. It tells about the people who made a great contribution at different stages of the transformation of DKF – a demonstration room in physics and MLDKS – an interfaculty laboratory of demonstrations and computer support. Bibliographic references to catalogs with methodological descriptions of lecture demonstrations developed and created at NSU are given.

We have achieved a power conversion efficiency of 16.44% for the ternary polymer solar cell using a wide bandgap copolymer and two non-fullerene acceptors.

Bio-inks consisting of pectin (Pec), carboxymethyl cellulose (CMC), and ZnO nanoparticles (ZnO) were used to prepare films by solution casting and 3D-printing methods. Field emission scanning electron microscopy (FE-SEM) was conducted to observe that the surface of samples made by 3D bioprinter was denser and more compact than the solution cast samples. In addition, Pec/CMC/ZnO made by 3D-bioprinter (Pec/CMC/ZnO-3D) revealed enhanced water vapor barrier, hydrophobicity, and mechanical properties. Pec/CMC/ZnO-3D also showed strong antimicrobial activity within 12 h against S. aureus and E. coli O157: H7 bacterial strains compared to the solution cast films. Further, the nanocomposite bio-inks used for 3D printing did not show cytotoxicity towards normal human dermal fibroblast (NDFB) cells but enhanced the fibroblast proliferation with increasing exposure concentration of the sample. The study provided two important inferences. Firstly, the 3D bioprinting method can be an alternative, better, and more practical method for fabricating biopolymer film instead of solution casting, which is the main finding of this work defining its novelty. Secondly, the Pec/CMC/ZnO can potentially be used as 3D bio-inks to fabricate functional films or scaffolds and biomedical applications.

This article discusses the development stages of a traveling wave-based fault location (FL) system on electricity transmission lines that monitors voltage signals only. This article also presents a 330 kV power network model with integrated FL equipment and the simulation results of transient processes caused by short failures in this network. A traveling wave-based FL algorithm that uses a statistical method to determine the time of traveling wave arrival at the place of FL system installation is developed. The factors that affect the accuracy of wave-based FL based on signals from capacitive voltage transformers are analyzed.

The advantages and disadvantages of existing solutions for calculating lighting fixtures (LF) are discussed in the paper. The methods for solving the global illumination problem are demonstrated. The most important illumination models used to calculate LFs have been analyzed. The Torrance-Sparrow model is used as the primary model of reflective surface. The triangulation method based on approximation of the LF surface by a grid of triangles is used to increase the efficiency of LF design and computation. The optical ray propagation in a 3D optical system was modelled using classical laws of optics and the Monte Carlo method. The structure and the main steps of working with the library for CAD Kompas are described. The approximation of LF surface for different types of light sources and reflector parameters is presented. The implementation of approximations with subsequent ray tracing has demonstrated a good convergence of the problem solution. The results of the study have the potential to be useful for design engineers involved in the design and calculation of LFs, as well as developers of applied software in the field of computer graphics and computer-aided design systems.

The objective is to describe clinical observations and literature data of possibility of using stent retriever technologies as a new treatment for cerebral vasospasm. Materials and methods . In the period from January 2017 to May 2019, 117 patients in the acute period of subarachnoid hemorrhage were treated at the Interregional Clinical Diagnostic Center (Kazan). Clipping was performed in 59 patients, endovascular occlusion in 58 patients. Vasospasm of varying severity estimated according to transcranial Doppler ultrasonography was observed in 115 (98.2 %) patients. Stent-assisted angioplasty was performed in three patients with vasospasm refractory to medical therapy using stent-retriever pRESET (Phenox, Germany). Results . The clinical efficacy of stent-assisted angioplasty with decreasing in speed indicators according to transcranial Doppler ultrasonography and neurological symptoms was achieved in all patients. No complications were observed. Conclusion . Stent-assisted angioplasty of cerebral arteries using stent retriever technologies is an additional option for the treatment symptomatic vasospasm in the acute period of subarachnoid hemorrhage.

Mirrors for light transmittance will be used in more than 30 optical and laser diagnostics installed in the ITER tokamak reactor. Their reliable performance depends largely on the degradation rate of the first mirror directly facing the plasma. The fluxes of neutral atoms, mostly D, T, and Be, from the plasma are the most dangerous for the first mirror. The interaction with the high-energy atoms can lead to sputtering of the mirror surface; redeposition of beryllium sputtered from the walls of the vacuum chamber can lead to the formation of a film on the mirror. This paper gives a conservative estimate of the degradation rate of in-vessel mirrors in the equatorial channels of the H-alpha and Visible Spectroscopy diagnostics. Calculations were performed for stationary ITER operation using the Zemax OpticStudio program. The results show that the working area of the first mirror will be sputtered at a rate of no more than 100 nm/year, which is an acceptable erosion load for mirrors made of single-crystal molybdenum. Beryllium film formation is expected only at the edges of the mirror (outside the working area). Possible contamination of the working part of the mirror as a result of accidents or plasma events can be eliminated using the mirror cleaning system installed into the first mirror unit. For the other in-vessel mirrors, the estimate predicts no significant degradation owing to their location at a long distance from the plasma.

This study is an attempt to suggest a new state system of permafrost monitoring, primarily for energetic infrastructure, based on past approaches and achievements in Russia for over a hundred years of Arctic studies. The methodology of this study is based on general theoretical methods of scientific research. Historical (retrospective analysis of the development of the monitoring system of long-term permafrost in Russia) and logical (inductive generalization) methods were applied. The structure and methods of permafrost monitoring in the Soviet Union and new technologies used nowadays to establish permafrost monitoring systems, taking into account modern Arctic energetic development, have been analyzed.

Using broadband acoustic resonator spectroscopy, an almost twofold increase in the frequency of optimal excitation of the composite microwave resonator of shear bulk acoustic waves is found when the distance from the substrate to the magnetron axis during the deposition of a ZnO film by magnetron sputtering is changed. The frequency characteristics of the resonator structure are simulated and an explanation of the change in the optimal excitation frequency by the inhomogeneity of the inclination of the ZnO film texture’s axis over the thickness is proposed.

In this study, we analyzed the efficacy of the most common methods of conservative treatment and orthopedic correction of an ingrown toenail at early stages used in outpatient surgical practice. We evaluated treatment outcomes and compared them using the methods of evidence-based medicine. We found that the orthopedic approach is significantly more effective than conservative treatment.

The paper presents the study results of the effect of carbon fibers with mechanically activated bentonite on the physical and mechanical properties, and tribological characteristics of polytetrafluoroethylene. It is shown that the introduction of combined fillers (carbon fibers with bentonite) in polytetrafluoroethylene leads to a significant improvement in the wear resistance of the material while maintaining a low friction coefficient. Structural studies of a worn surface by IR spectroscopy and scanning electron microscopy indicate: the localization of carbon fibers and activated bentonite particles on friction surfaces with the formation of wear-resistant secondary structures; the progress of tribochemical reactions with the oxidation of fragments of the PTFE tribodecay; and the subsequent structuring of surface layers.

Objective a retrospective assessment of the bedsores' features, the optimization of treatment tactics, evaluation of long-term treatment results. Material and methods.The study group included 38 patients with stage IV decubitus ulcers according to the classification of AHCPR localized in the sacral region, the area of the ischial tuberosity and the greater trochanter. Results.We determined the critical time intervals for the decubitus ulcers occurrence. It has been found that in most patients bedsores are remaining for a long period of time. The modern complex methods for the IV stage decubitus ulcers treatment with the plastics of the soft tissue defects revealed their reliably higher effectiveness. Conclusion.The formation of bedsores most often occurs during the first month after the injury and three years after the injury. The treatment of patients with this pathology should be comprehensive and carried out in the well-equipped purulent surgery department by the specialists experienced in treating such patients. The plastic surgery by displaced blood-supplying flaps contributes to success in the treatment of stage IV bedsores.

the stability of the dam on Rogunskaya HPP made of ground materials is studied on the basis of numerical calculations of its spatial stress-strain state. The deformation and strength properties of the materials composing the dam body defined in the triaxial compression devices were used in the calculations. Limit values of strength properties of materials and controlled values of diagnostic indicators of a dam at which safety of its work is provided are established.

This paper presents the results from the investigation of effect the carbon fibers with tungsten disulfide on the mechanical and tribological properties of PTFE. Is carried out a comparison of mechanical and tribological properties of polymer composites PTFE-based with carbon fibers and PTFE with complex filler (carbon fibers with tungsten disulfide). It is shown that at a content of 8 wt.% CF+1 wt.% WS2 in PTFE, wear resistance increases significantly while maintaining the tensile strength, relative elongation at break and low coefficient of friction at the level of initial PTFE. The results of X-ray analysis and investigation of SEM supramolecular structure and friction surfaces of PTFE and polymer composites are presented. It is shown that the degree of crystallinity of polymer composites increases in comparison with the initial PTFE. The images of scanning electron microscope reveal that particles of tungsten disulfide concentrating on the friction surface is likely responsible to a reduction in the coefficient of friction and increase the wear resistance of PTFE-based polymer composites with complex fillers.

The degradation of an AlMg6M alloy, which is used as the material of the bottoms of large tanks, during long-term operation is considered. The yield strength of the alloy increases, the plasticity decreases, and the impact toughness decreases in comparison with the same characteristics estimated after the annealing imitating the initial state of the material. The degradation of the mechanical properties is associated with structural changes, which is confirmed by the study of the microrelief of the fracture surfaces of alloy specimens.

The results of works published in the open press over the past 100 years on the possibilities of converting one of the most well-known and widely used blasting explosives (EX) – 2,4,6-trinitrotoluene (TNT, TOL, TNT) into "conversion" chemical products are summarized having a diverse and commercially attractive application. Examples of the first industrial use of TNT are not given as explosives, but as inexpensive and affordable chemical raw materials for the production of components of photosensitive compositions. The reasons for the second more intensive period of development of works (late 20th – early 21st centuries) on revealing the synthetic potential of TNT are noted. The most promising areas of work are discussed: the synthesis of polyfunctional organic compounds of a carbo (hetero) cyclic structure, interesting as biologically active substances, precursors for the synthesis of pharmaceuticals, original polymers and resins, etc. The article makes assumptions about the reasons for the fact that so far TNT has not found wide practical application as an almost universal starting compound for obtaining a wide range of products of small and large-tonnage organic intesa. Using examples of the results of their own work on obtaining original, effective dyes and pigments, sorption-active compounds, structural analogues of hard-to-reach, but practically significant natural substances, the authors suggest ways of involving TNT in the practice of industrial organic synthesis.

Graphite is widely used in the atomic industry and nuclear power engineering. In the next 10–15 years, the resource of most blocks in the uranium–graphite reactors in Russia will be exhausted with allowance for the elongation of the service life, as follows from the results of repair-and-renewal operations. High-activity graphite can be processed by flameless oxidation in molten salts. The purpose of this work is to study the behavior of radionuclides during the flameless oxidation of radioactive graphite in the CuO–NaCl–KCl–Na2CO3–K2CO3 melt in water vapor using a thermodynamic simulation and the Terra software package. A thermodynamic simulation is an effective and unique method used to investigate diverse high-temperature processes of thermal decomposition, reduction, and synthesis. The calculation is performed using a reference datable of the properties of individual substances. Graphite burns up at 573 K. The condensed compounds of cesium, chlorine, and uranium evaporate at 1673 K. An increase in the temperature to 1973 K leads to the vapor pressure of the condensed compounds of beryllium, calcium, and strontium. The condensed oxide of europium(III) and the condensed oxide of plutonium(IV) transform into a vapor state at 2173 K. The condensed oxide of nickel transforms into a vapor state at 2473 K. A further increase in the temperature to 2773 K leads to the transformation of the condensed oxide of americium(III) into a vapor state. Only a vapor–gas phase is present in the isolated system in the temperature range from 2773 to 3273 K.