Search

A co-precipitation method is proposed for the synthesis of highly crystalline BiFeO3 (BFO) nanoparticles with varying Bi/Fe molar ratio (0.9, 1.0, 1.1) after calcination at 550 ◦C and 600 ◦C in air. The effect of the varying Bicontent on the phase constitution, structural and multiferroic properties of the nanoparticles is investigated. Differential thermal analysis discloses that the crystallization of the initially, amorphous, powder occurs at 484 ◦C, whereas the Curie temperature is 820 ◦C. X-ray diffraction patterns and Fourier transform infrared spectra evince the formation of the rhombohedral structure with R3c space group symmetry in all samples, whereas Rietveld refinement confirms the phase purity of the 600 ◦C calcined BFO at Bi/Fe = 1.0. Transmission electron microscopy indicates that the average particle size is tuned with respect to calcination temperature and Bi content, giving rise to the enhanced magnetic properties of the 550 ◦C calcined BFO 0.9 at room temperature due to size effects and an increment of structural distortions. By rising the Bi-content, the surplus Bi stabilizes the highly polar R3c rhombohedral structure at both calcination temperatures, resulting in the enhanced values of the real (ε′ ) dielectric constant in BFO 1.0 and BFO 1.1 at room temperature. UV–visible absorbance spectra of both 550 ◦C and 600 ◦C calcined BFO 1.0 exhibit strong visible light absorption, while the corresponding Tauc’s plots manifest that the optical band gap energy of BFO nanoparticles is about 2 eV following particle size trends.

Introduction. The high frequency of complicated forms of the stomach and duodenum peptic ulcer (PU) in patients with atherosclerosis requires the study of additional factors of ulcerogenesis in addition to infection with Helicobacter pylori (H. pylori) and the use of non-steroidal anti-inflammatory drugs (NSAIDs). Currently, there is no clear understanding of the role of mesenteric artery (MA) atherosclerosis in the development of gastroduodenal ulcers. The purpose of the study. To evaluate the contribution of MA atherosclerosis to the development of gastric and duodenal ulcer in patients with multifocal atherosclerosis. Material and methods. The study included 91 patients with atherosclerosis of two or more vascular beds in the period from 2019 to 2021. The examination included the determination of the gastrin-17, pepsinogen I, pepsinogen II and antibodies to H. pylori IgG concentration in blood serum, as well as multispiral computed tomoangiography of the abdominal aortic branches and esophagogastroduodenoscopy with histological examination. Results. The patients were divided into two groups: group I – 36 (39.6%) patients with PU, group II – 55 (60.4%) patients without PU. A more frequent occurrence of hemodynamically significant stenosis of the MA and a higher percentage of the superior mesenteric artery (SMA) stenosis in group I were noted. A positive correlation was found between the severity of erosive and ulcerative lesions and the percentage of SMA stenosis, levels of pepsinogen I and pepsinogen II. The combination of PU and MA atherosclerosis is characterized by a lesser severity of abdominal pain syndrome (p = 0.049). Risk factors for PU were identified: MA atherosclerosis (OR 4.953; CI 1.571–15.608); more than 8 points on the HADS depression scale (OR 2.970; CI 1.062–8.320) and on the Audit questionnaire (OR 5.787; CI 1.348–24.837). Conclusions. Risk factors for PU in patients with multifocal atherosclerosis were identified: MA atherosclerosis, subclinical depression, and health-threatening alcohol consumption. PU in patients with multifocal atherosclerosis is characterized by asymptomatic course.

In the context of rethinking globalization, the negative features of the world order model formed by this process and, as a result, the emerging characteristics of a new more harmonious model come to the fore. The purpose of the article is to outline the post-global world, but not as a model of the world order following after a certain time period behind the global world, but as a model of the world order with new qualitative characteristics that eliminate the shortcomings of the previous model. Such a characteristic as multipolarity is presented in more detail, in the formation of which took into account the reports of the V International Scientific and Practical Conference "Greater Eurasia: National and Civilizational Aspects of Development and Cooperation" (University of World Civilizations, Moscow, November 23–24, 2022). Since the literature is dominated by a political approach to multipolarity, the authors attempted to shed more light on the economic aspect of the problem. The hypothesis of polycentricity in integration associations is also developed.

Мета роботи: Мета статті полягає у визначенні особливостей теоретичних аспектів визначення критеріїв воєнно-економічної ефективності в задачах обґрунтування вибору раціональних варіантів складних зразків озброєння та військової техніки (літак, танк, корабель, зенітно-ракетний комплекс, реактивна система залпового вогню тощо). Метод дослідження: основними методами досліджень є методи аналізу та синтезу, методи воєнно-економічної теорії, методи дослідження операцій, метод воєнно-економічного аналізу. Результати дослідження: У статті наведені основні теоретичні погляди авторів щодо визначення воєнно-економічних критеріїв обґрунтування вибору раціональних складних зразків озброєння і військової техніки (літак, танк, корабель тощо) із наявних альтернативних пропозицій з метою їх подальшого серійного виробництва. Також у статті сформовані основні вимоги до воєнно-економічних критеріїв, наведено підхід до їх класифікації та розкриті особливості їх застосування. На основі теоретичних аспектів методу воєнно-економічного аналізу під час обґрунтування технічних рішень запропоновано порядок формування послідовності ієрархічної оптимізації за обраними критеріями із урахуванням особливостей їх застосування. Теоретична цінність дослідження: основними результатами досліджень за тематикою статті є: визначені теоретичні особливості застосування воєнно-економічних критеріїв в області прийняття технічних рішень щодо вибору складних зразків озброєння і військової техніки; сформовані основні вимоги до воєнно-економічних критеріїв; наведено підхід до їх класифікації; розкрито особливості їх застосування. Тип статті: теоретичний, описовий, практичний, методичний.

The improvement of regulatory framework for attracting a specialist to participate in criminal proceedings on the initiative of the defense and other participants in the process who do not have authority is reasonably considered in theory and in practice as an extension of the adversarial principles in the procedures for the use of special knowledge. At the same time, the noticeable bias observed in modern law practice towards the use of expert opinions and testimony in the interests of principals to the detriment of lawyer activity in official procedures for the appointment and production of forensic examinations cannot be considered justified. Seeking the help of a specialist is not an equivalent substitute for participation in forensic expert activities in criminal cases, but rather a forced measure when attempts by a lawyer to participate in the appointment and production of examinations were impossible, or were undertaken, but failed.

Aim. To assess whether the internal thoracic artery (ITA) is able to protect coronary artery (CA) after coronary artery bypass graft (CABG) surgery.Material and Methods. Having performed coronary angiography in the long term after CABG surgery, we evaluated 102 angiograms by visual analysis and using Gensini score and SYNTAX score. Using these parameters, we investigated the association of internal thoracic artery and saphenous vein grafts with anatomy and pathology of the coronary artery.Results. Calculation of Gensini score revealed that use of ITA grafts was associated with mild coronary atherosclerosis [4 (0; 17)] as compared with SV grafts [32 (2 ; 32)]. Relative increase of atherosclerotic burden in the coronary artery was 21.05% for the ITA grafts and 102.87% for the SV grafts. Lesion growth rate was significantly higher after using SV grafts than in case with ITA grafts (p = 0.0002)Conclusion. ITA grafts reduce progression of atherosclerosis in bypassed coronary arteries in comparison with SV grafts.

Various industries are widely using the austenitic stainless steels, and these steels possess the potential to improve their mechanical properties through alloying and deformation machining. However, such material improvement could also affect the quality of its machine cutting. The paper studies the influence of intensive plastic deformation on structure and properties of the 08X18H10 steel alloyed with copper and manganese, as well as on the quality of its machining in turning under different structural states. It was established that the use of multilateral forging led to formation of a heavily deformed subgrain structure with the high dislocation density in the steel under study, and subsequent rolling caused additional formation of the differently oriented deformation microtwins and packs of nanotwins. These structural alterations contributed to increasing the strength and micro-hardness of the material. Analysis of the machine turned surface relief of the samples showed that using the intensive plastic deformation made it possible to significantly reduce the Ra and Rz roughness parameters compared to those samples not subjected to intensive plastic deformation. It was found that an increase in feed led to the growing micro-hardness of the material thin near-surface layer and to its smoother alteration in depth from the machined surface.

The influence of the size of dislocation loops on sublattice ferrimagnetism in graphene is studied. It is shown that graphene and the underlying gold layer with Au/Co dislocation loops of various sizes are characterized by ferrimagnetic ordering within atomic layers. Additional gold adatoms under graphene enhance the induced Rashba spin–orbit coupling in graphene but do not destroy the ferrimagnetic order in graphene. Since gold clusters can remain during the intercalation of gold on the surface of graphene and under graphene, the number and size of clusters after intercalation can be controlled to enhance the induced Rashba interaction and to obtain a topological phase in graphene.

The article reveals the key characteristics that distinguish Russian civilization from others.

The aim of the work is to construct a computational scheme of the finite element method in relation to integral equations describing current distributions in thin wire antennas. In particular, for linear antennas of small thickness, the problem can be reduced to the integral Gallen equation. As a research method, preference is given to the finite element method, since it has quite a lot of flexibility in terms of choosing basis functions and selecting a grid of nodes. In addition, this method is a powerful and effective means of solving mathematical physics’ problems, which makes it possible to accurately describe complex curved boundaries of the solution domain and boundary conditions. The paper builds a numerical method for solving the integral Gallen equation using the finite element approach. According to the proposed computational scheme, a software implementation was built and a comparative analysis of the results was carried out. This approach as a whole showed low accuracy, which is probably due to the fact that this problem belongs to the class of incorrect ones and, in general, is due to the issue of determining the limits of applicability of the Gallen equation.

The article shows the role of education as an element of culture in the context of ongoing transformational processes in the world.

Highlights. Despite high hospital mortality after coronary bypass grafting in patients with high-risk non–STsegment elevation acute coronary syndrome, surgical myocardial revascularization remains a preferable treatment modality since percutaneous coronary intervention in these patients is associated with high perioperative complications due to severely calcified coronary lesions.Background. The optimal revascularization strategy in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) remains the subject of many years of controversy. Coronary artery bypass grafting (CABG) improves the long-term prognosis through complete revascularization, however, percutaneous coronary intervention (PCI), due to its availability and low invasiveness, suggests an improvement in hospital outcomes.Aim. To compare hospital outcomes of CABG and PCI performed within 24 hours in high-risk NSTE-ACS patients.Methods. In the present study, the first group included 30 NSTE-ACS patients who underwent CABG in the first 24 hours (the CABG group), whereas 30 NSTE-ACS patients who underwent PCI were included in the second group (the PCI group).Results. The mean age was 64,4±7,3 years, it was comparable in both groups. The main clinical and anamnestic characteristics of patient in both groups were comparable as well. The severity of coronary atherosclerosis according to the Syntax score was 25,6±9,2 in the CABG group, and 21,7±5,7 in the PCI group (p = 0,054). After revascularization, the residual Syntax score did not differ between the groups (p = 0,42), indicating complete revascularization. Hospital mortality was relatively high in the CABG group (13,3%), while no such cases were noted in the PCI group. Most of the patients with adverse outcomes had a critical lesion of the left main coronary artery and a complicated postoperative course.Conclusion. The results of this study demonstrate promising outcome of CABG in patients with severe multivessel coronary disease at high risk of adverse events.

The article analyzes the cultural aspect of the ongoing geopolitical transformation in the world, as well as the impact of these processes on Russia.

Purpose. To evaluate the regeneration of an infected skin wound in experimental steroid hyperglycemia in rats.Materials and methods. Regeneration of an infected rat skin wound (n = 30) was evaluated on the background of steroid hyperglycemia. Depending on the type of wound surface treatment, all observed animals were divided into 3 groups: the first group (n = 10) was treated with an ointment containing Cymbopogon proximus per os administration; the second group (n = 10) was treated with an ointment containing sodium fusidate 2 %; the third group (n = 10, control) the wound was treated with vaseline. After five days, local changes in the wound area and the activity of its regeneration were evaluated. We also studied the blood changes: the composition of the shaped elements and the content of total protein, albumins, transaminase activity (ALT, AST), total cholesterol, urea and creatinine.Results. The use of Cymbopogon proximus orally by rats of the first group, with induced diabetes mellitus, contributes to a decrease in serum glucose levels by almost two times compared with the second and third groups. Ointment containing Cymbopogon proximus has immunomodulatory properties: it prevents the development of leukopenia, promotes the activation of agranular immunocytes. The use of Cymbopogon proximus extract has a positive effect on the rate of wound regeneration due to several factors: reduction of hyperemia and edema, stimulation of leukocyte activity, and as a consequence activation of regeneration. We did not find a significant difference in the rate of wound regeneration when treated with an ointment based on Cymbopogon proximus extract and an ointment containing sodium fusidate (p > 0.05).Conclusion. The regeneration activity of an infected wound in rats with steroid hyperglycemia does not significantly differ when treated with antimicrobial ointment and Cymbopogon proximus. The extract of Cymbopogon proximus has a double effect in vivo: it reduces glucose levels and promotes wound healing in the condition of hyperglycemia, which is promising in the treatment of complications in diabetes mellitus.

Objective: to analyze the results of a morphological study of the lung tissue and small airways in the surgical material of patients with a combination of tuberculoma and nontuberculous mycobacteriosis of the lungs caused by different types of pathogen.Materials and methods. A comparative retrospective histological study of the surgical material of 34 patients with a combination of LT and NM with established microbiological different types of non-tuberculous mycobacteria (NTMB) and 36 patients with LT without concomitant pathology was carried out.Results. Diagnostically significant differences in the morphological picture of TL and NM, which manifests its morphological features in areas free from foci of tuberculosis, were revealed. The features of changes in the lung tissue and small airways in patients with slow- and fast-growing types of NTMB are shown.Conclusion. The results obtained are aimed at resolving the issue of possible correction of chemotherapy in the postoperative period.

The purpose of the article is to study art techniques and means of expression of neo-noir and post-noir in the cinematography of the late XX — early XXI centuries. The subject of analysis are noir phenomena — the latest and postmodern processes in cinema, based on the aesthetic, genre and style canon of noir. Noir phenomena in the language of cinematography could not remain within the narrow limits of the aesthetics of “black” cinema. That is why they became a space of transformations: stylistic, genre, narrative, semantic, etc. The methodology of theoretical analysis in this article is based both on the whole complex of ideas related to the subject of research, and on specific scientific tools. The study is part of a more general research case, which focuses on the analysis of the phenomenology of “black cinema” (or noir) in the cinema of the late XX — early XXI centuries. In a separate publication, the authors of this study investigated the issue of “genre memory” of noir. Also, a part of the research case is the problem of analysis of expressive means and artistic techniques in cinematography of the late XX — early XXI centuries. This problem was also considered by the authors of the study in a series of publications devoted to the “collage” artistic language of the Ukrainian director S. Paradzhanov. The methodological basis of the article relies on the research of Western scientists: Gavin Smith, Charles Scruggs, Jean-Pierre Chartier, Simon P. Otieno, David Copenhafer, Mary P. Wood, Lisa Colpaert, Thomas Leitch, James McRoy, Emily R. Anderson. The results. Our definition of the set of basic techniques and expressive means of “noir” phenomena in the cinematography of the second half of the XX — beginning of the XXI centuries allows us to distinguish three spatial-compositional systems that characterize the specifics of noir, neo-noir and post-noir. In the first case, we observe a linear unfolding of the action, within which scenes and framing are in a direct cause-and-effect relationship. In the context of neo-noir, compositionality is a question of the specific action topos of the film; despite the existence of general rules and characteristics of working with planes and space, the general impression of “panoramity” and different scales is dominant. Post-noir aesthetics is formed in the plane of a greater variety of artistic techniques, which is connected with the practical absence of “canonical” boundaries and the property of post-aesthetics to combine various effects, means (and in some cases to resort to “citation” and “redefinition”). The scientific novelty of the research lies in the fact that the formation of artistic symbolism and imagery of neo- and post-classical noir aesthetics as a system is investigated for the first time. The authors analyze the specifics of expressive means of neo-noir and post-noir, which unite the phenomena into one whole. The practical significance of the article is that the conducted scientific analysis makes it possible to reveal the forms of representation of “noir” phenomena in modern cinema.

The potential shift appears at frame antenna during plasma creation in Uragan-2M torsatron. This paper provides experimental study of that potential dynamics (Ump). The measurements showed that Ump value can be both positive and negative. The dependency of Ump from RF generator feeding voltage and working gas pressure is given. The cause of positive Ump value is identified.

Introduction. Additive technologies make it possible to curb material expenses by reducing allowances for the final dimensional machining of workpieces. For such expensive materials as copper and copper alloys, this method is considerably attractive from a perspective of increasing resource efficiency in production. The operational properties of the C65500 alloy manufactured using additive technologies have not been fully studied and require additional research. The aim of the work is to study the structural and phase state, mechanical and operational properties of C65500 bronze specimens printed using electron beam additive manufacturing technology. In the work, specimens made of C65500 wire with different heat input values are studied, some of which were subjected to thermal treatment and mechanical processing, as well as specimens, manufactured using multi-wire technology. The work uses such research methods as the study of corrosion resistance of bronze specimens using a potentiostat, confocal laser scanning microscopy, friction tests and X-ray phase analysis. Results and discussion. Processing of specimens by plastic deformation (compression) and subsequent annealing leads to the most serious structural changes. Based on X-ray phase analysis, it is found that higher silicon content is observed in the case of the addition of silumins to bronze. The study of mechanical properties shows that the specimens, printed using multi-wire technology, have the highest strength properties. During tribological testing, fluctuations in the value of the friction coefficient are revealed, due to the scheme of the experiment and the combined adhesive-oxidative mechanism of specimens’ wear. The addition of 10 wt.% aluminum filament to bronze in the additive manufacturing process is an effective means for increasing the resistance of the material to electrochemical corrosion and increasing its wear resistance.

An observation from practice is given – surgical treatment of mediastinal pulmonary hernia in a patient after pneumonectomy using the method of anterior mediastinal plastic surgery with a mesh implant with demonstration of long-term results.The patient I. 31 years old was ill with pulmonary tuberculosis for 3 years, treatment was carried out, against which the stenosis of the left main bronchus progressed. The patient underwent endoscopic operations: argonoplasmic destruction of the left main bronchus, balloon dilation of the left main bronchus, with a temporary effect. Due to recurrent stenosis of the left main bronchus, a pneumonectomy was performed on the left. After 7 months, she complained of severe shortness of breath at rest. Computed tomography revealed a displacement of the mediastinal organs to the left, an upper-anterior pulmonary mediastinal hernia of the right lung to the left midclavicular line at the level of the anterior I-IV intercostals on the left. The patient underwent plastic surgery of the anterior mediastinum on the right using a polymer mesh implant. As a result of treatment, after 3 years, radiologically stable restoration of the position of the only right lung in its hemithorax. The patient is functionally compensated, shortness of breath is not observed. The patient has completely returned to her usual lifestyle.

The aim of this work is to evaluate diagnostic value of liver non-contrast perfusion in prediction of visceropathies (sialadenitis and hepatic encephalopathy) in patients with diffuse liver diseases (DLD). Clinical and laboratory data (including the Raitan test), results of MRI with non-contrast MR perfusion (ASL-perfusion) of the liver and brain MRI with assessment of the head and neck soft tissues were estimated in a group of patients with DLD. Potentials of assessment of ASL liver perfusion for hepatic encephalopathy and sialadenitis prediction are described in the article. Based on the clinical and laboratory data and results of histopathological analysis of salivary gland biopsies, it was established that sialadenitis in patients with DLD is the result of disturbance of macroorganism resistance; sialadenitis in this context is the inflammatory process of the gland with acinuses atrophy signs, in MRI it forms pictures of the gland enlargement without visible macrostructure changes. The study showed that the integrated approach to observation of patients with DLD (radiologist + gastroenterologist / infectious disease specialist + otorhinolaryngologist / dentist) helps correct of patient monitoring tactics timely and effective.

—The paper discusses current state of the spectral approach to analysis of induced polarization (IP), its possibilities and limitations, along with directions for the method development. Reviewed are the main methods and approaches for estimation of spectral IP parameters and their specific features. Our practical experiments have shown the advantages of analysis of transient IP characteristics over standard approaches to the IP data analysis and processing. Results of the standard and spectral approaches application to analysis of IP data when solving mineral exploration problems at the Maletoyvayam gold deposit (Kamchatka Peninsula) and the Yasnoe gold occurrence (Taimyr Peninsula) are compared. Here, we demonstrate that low efficiency of works is erroneously regarded as one of the main factors hindering a broad adoption of the spectral IP method in mineral exploration activities. Rather, it is a lack of automated techniques for analysis of transient IP characteristics. We propose a new approach to spectral analysis of IP data, based on the algorithms for image recognition of a reference object, and describe pioneering efforts of its practical application.

The article considers the balance of the engine oil aging components in the diesel engine lubrication system with the refinement of oil composition caused by the oil product loss. The motor oil aging process has been identified under continuous and periodic oil refill in order to replenish the lubrication system with fresh oil which would compensate the burnt off oil products. There were derived and solved the differential equations of the oil product balance for such aspects of aging as contamination by insoluble impurities and multifunctional additives impact, which helped understand the general regularities and kinetics of the studied process. Novelty of the approach to theoretical description of the process consisted in the fact of filtering the insoluble and colloidal components of mechanical impurities and additives by the purification and burnout means. Cyclic picture of aging allows to analyze the state of the oil aging before and after refill with its periodic refreshment. The dependence is transformed and presented in a form where it is possible to determine the state of the oil at each aging cycle, without examining the intermediate concentrations of impurities and additives. The advantage of the obtained kinetic integral expressions for oil aging is the ability to determine the conditions for a long-term or permanent mode of its use in the lubrication system of a diesel engine. There are given the formulas by which the intensity of filtration and the concentration of additives in fresh oil or the time of their impact are calculated at a given oil loss and provide a pre-rejection mode of using circulating luboil in a diesel engine.

This Expert Council focuses on the meta-analysis of studies on the risk of atrial fibrillation (AF) in patients taking omega-3 polyunsaturated fatty acids (PUFA) and of data on the omega-3 PUFA treatment in patients with cardiovascular and kidney diseases.The major statements of the Expert Council: the meta-analysis of AF risk in patients taking omega-3 PUFA showed an increased risk of this arrhythmia. However, it should be taken into account that the risk of complications was low, and there was no significant increase in the risk of AF when omega-3 PUFA was used at a dose of ≤1 g and a standard dose of the only omega-3 PUFA drug registered in the Russian Federation, considering all AF episodes in the ASCEND study.At the present time, according to Russian and international clinical guidelines, the use of omega-3 PUFA can be considered in the following cases: • for patients with chronic heart failure (CHF) with reduced left ventricular ejection fraction as a supplement to the basic therapy (2B class of recommendations according to the 2020 Russian Society of Cardiology guidelines (RSC) and the 2022 AHA / ACC / HFSA guidelines); • for patients with hypertriglyceridemia (>1.5 mmol/l) as a part of combination therapy (IIb class of recommendations and B level of evidence according to the 2021 European guidelines on cardiovascular disease prevention, etc.); • for adult patients with stage 3-4 chronic kidney disease (CKD), long-chain omega-3 PUFA 2 g/day is recommended for reducing the level of triglycerides (2C class of recommendations). Data on the use of omega-3 PUFA for other indications are heterogenous, which can be partially explained by using different form and doses of the drugs.

Данная работа посвящена развитию численного подхода к моделированию стадии «тонкой» фильтрации водной среды, следующей за прохождением механических фильтров. На этом этапе очистки водная среда подвергается электромагнитному или тепловому воздействию. Для анализа процессов очистки предлагаются математические модели течения жидкости с учетом тепловых эффектов, эволюции концентрации загрязнителя в условиях развитых конвекционно-диффузионных процессов и при наличии квазистатического электрического поля. Для описания течения водной среды, содержащей частицы твердых мелкодисперсных примесей, используется квазигидродинамическая модель, дополненная уравнениями конвекциидиффузии-реакции. Численная реализация модели в случае трехмерной декартовой геометрии основана на методе конечных объемов на нерегулярных тетраэдральных и призматических сетках и ориентирована на применение параллельных вычислений. В качестве примеров использования разработанной компьютерной технологии моделирования рассмотрены задачи электромагнитной очистки водной среды и загрязнения теплоэлектронагревательного (ТЭН) элемента. В первой задаче рассчитана зависимость концентрации загрязнителя от времени, которая демонстрирует эффект очистки и позволяет оценить ее степень в зависимости от параметров электрического поля. Во второй задаче исследовался процесс образования накипи и последующей регенерации ТЭНа. Проведенные расчеты показывают, как происходит загрязнение ТЭНа и как при воздействии соляной кислоты происходит его очистка. Эти данные позволяют уточнить параметры перспективных установок замкнутого цикла, в которых чередуются циклы нагрева среды и регенерации нагревательных элементов.

Highlights. Using ECHO and MSCT data, a numerical assessment of hemodynamic effects of paraprosthetic regurgitation following transcatheter aortic valve replacement was performed. A significant increase in the fluid flow, wall and viscous shear stresses in the area of regurgitation is shown. The modeling technique described in the paper can be used prospectively in assessing the optimal treatment modality in terms of predicting the quantitative characteristics of the flow, associated with the risks of destruction of red blood cells and thrombosisAim. To make a numerical assessment of hemodynamic effects of paraprosthetic regurgitation following transcatheter aortic valve replacement based on retrospective clinical data.Methods. The study included echocardiography and multi-slice computed tomography data as input data for modeling one pulsation of a fluid similar in properties to blood. Reconstruction of the paraprosthetic fistula and the ascending aorta was performed in the Mimics medium (Materialise, Belgium). The obtained 3D models were processed in the Salome software (OPEN CASCADE SAS, France), after which they were exported to HELYX-OS (ENGYS, Great Britain) to build a finite element mesh. The flows were modeled using the OpenFOAM software package version 6 (The OpenFOAM Foundation Ltd, UK).Results. The simulation result, expressed quantitatively and qualitatively in the form of diagrams of the measured parameters – fluid flow velocities, wall and viscous shear stresses, shows a significant increase in indicators in the area of paraprosthetic regurgitation. Thus, the velocity in the affected area was 1.9–4.2 m/s, which is 3.8 higher than the average value in the entire computational area. The wall shear stress value was up to 61 Pa in the critical area, which may indicate an increased risk of thrombus formation due to the initiation of the clotting cascade through the von Willebrand factor. The value of viscous shear stress, the main component of the destruction of red blood cells in laminar flow, amounted to 20–26 Pa, which, in general, is not enough for mechanical hemolysis.Conclusion. The modeling technique described in the paper can be used prospectively in assessing the optimal treatment modality in terms of predicting the quantitative characteristics of the flow, associated with the risks of destruction of red blood cells and thrombosis.

The invention of the saddle substantially improved horseback-riding, which not only revolutionized warfare, but also eased long-distance speedy movement across Eurasia. Here we present the first detailed construction analysis and absolute age determination of a well-preserved soft leather saddle recovered from the tomb of a female deceased at the Yanghai cemetery site in the Turfan Basin at the eastern end of the Tian Shan mountains. Compared with the oldest known saddle from the Scythian Pazyryk culture site Tuekta barrow no. 1 (430–420 BCE) in north-western Altai, the Yanghai specimen radiocarbon dated to 727–396 BCE (95.4% probability range) is contemporaneous or possibly older. The saddle features the basic elements of soft saddle construction that are still used today: two stuffed, wing-shaped hides sewn together along the outer edges and separated by a central gullet-like spacer and lens-shaped support elements, resembling knee and thigh rolls of modern saddles. Being a masterful piece of leather- and needlework, it is, however, less complex compared to Scythian saddles from the 5th–3rd centuries BCE. Another specimen from nearby Subeixi site, which is also described in detail for the first time in the present study, much closer resembles the Pazyryk saddles in shape, size and structure. In Yanghai, equestrian paraphernalia appear in the grave assemblages during the entire burial period (ca. 1300 BCE to 200 CE), although in higher numbers only from ca. 300 BCE. In the same way, the burial of horses was not common until then. Despite the generally very good preservation of leather, only two saddles were discovered in Yanghai which makes them an exception rather than the norm and raises the question of whether these saddles were acquired from more specialized horse breeders, riders, and saddlers in the North. 1. Introduction 2. Material and methods 2.1. The leather saddle from the Yanghai archaeological site tomb IIM205 2.2. The leather saddle from Subeixi archaeological site tomb M10 3. Results and interpretations 3.1. Dating of the leather saddles 3.2. The saddle from Yanghai 3.2.1. Construction 3.2.2. Saddle panels 3.2.3. Gullet 3.2.4. Lens-shaped support elements 3.2.5. Type and preservation of leather 3.2.6. Saddle filling 3.2.7. Fastening of the saddle 3.3. The saddle from Subeixi 3.3.1. Construction 3.3.2. Saddle panels and gullet 3.3.3. Gussets and bone attachments 3.3.4. Girth 3.3.5. Crupper 3.3.6. Felt pad 3.3.7. Bridle 3.3.8. Leather type and saddle filling 4. Discussion 4.1. Comparison of the Yanghai and Subeixi saddles 4.2. Turfan in the evolution of saddlery in central and eastern Asia 4.3. Turfan in the early history of horse-riding in central and eastern Asia 5. Conclusions

The work presents a digital platform for supercomputer modeling the problems of spraying the particles on substrates. The purpose of this work is to discuss the general architecture, technology stack and implementation features of the platform's user interface. The platform is based on web technologies for access and management of calculations, which allow implementing a user system for conducting a full cycle of a computational experiment, including the configuration of applied applications, their launch on remote computing resources, monitoring the completion of tasks, analysis and interactive visualization of results. User interaction with computing resources is implemented through the graphical interface that does not require the client computer to have any additional software, except actual version of a modern web browser. An important advantage of the platform is the ability to make large-scale computer research in a multi-user mode that is based on the natural principles of building client-server applications. The presented digital web platform was successfully tested on computing clusters of the KIAM RAS in solving a number of the topical mathematical problems of nanotechnology. Also, with its help, for the last 3 years, group training of MIPT students in modern information technologies has been carried out.

A comparative study of the characteristics of two fiber-filled molding materials, which include a discrete carbon viscose fiber as a filler and phenol-formaldehyde resins of the novolac or resol type as a binder, is given. The DTA-DTG characteristics of the initial resins and the physico-mechanical properties of carbon fiber blanks obtained from fiber-filled molding materials of these types by hot compression molding were determined. It has been established that, regardless of the type of phenol-formaldehyde resin, the density, strength characteristics, toughness and thermal conductivity of carbon fiber plastics based on various resins are practically the same. A comparison of the microstructure of the obtained carbon fiber plastics based on various resins showed that in the case of using phenol-formaldehyde resin of the novolac type, a higher degree of orientation of the fiber filaments parallel to the pressing plane is achieved, which is associated with greater fluidity of the initial fiber-filled molding material. In the direction perpendicular to the pressing axis, the chaotic orientation of the fiber filaments is realized.

The presented observation describes an example of effective treatment of the patient with disseminated destructive pulmonary tuberculosis with preXDR. The treatment included staged surgery using the original method of anterior mediastinum plasty with a mesh implant.The treatment resulted in the following outcomes: stabilization of the tuberculous disease, persistent sputum conversion, minimization of overdistension of the only lung, absence of mediastinal pulmonary hernia and no deterioration of respiratory function.

Background. Coronary artery bypass grafting (CABG) remains the most common cardiac surgery in the world. In the long-term follow-up period after surgery, graft failure occurs in a substantial proportion of CABG conduits and is a complex pathomorphological process. Optical coherence tomography (OCT) is a high-resolution intravascular imaging modality that allows to assess in-vivo endothelial integrity.Aim. To substantiate the efficacy and safety of OCT assessment of the conduitanastomosis-artery system in CABG patients.Methods. The prospective observational cohort study included 21 patients with chronic coronary artery disease who underwent CABG. 3–5 days after CABG, patients underwent OCT and angiography of arterial and vein grafts, including distal anastomosis and nearby segment of the target coronary artery. At 12-month follow-up, all patients underwent repeated OCT and angiography of the conduitanastomosis-artery system to assess the changes. The primary endpoint of the study was graft failure; secondary endpoints of the study included unplanned repeat myocardial revascularization, cardiac death, and myocardial infarction due to graft failure.Results. At 12-month follow-up, 14.3% of graft failure and 9.5% of cases of unplanned repeated myocardial revascularization were registered. In most cases of graft failure, primary OCT revealed pronounced changes in the conduit and the native coronary artery (conduit/artery diameter ratio was more than 2 mm), whereas the diameter of the coronary artery anastomosis was less than 2.5 mm. Myocardial infarctions and death within 12 months were not registered.Conclusion. Thus, OCT is an effective and safe intravascular imaging technique for assessing coronary arteries and the conduit-anastomosis-artery system. OCT makes it possible to identify morphological changes in coronary bypass grafts, which can predict their early failure. The conduit/artery diameter ratio greater than 2 and target coronary artery diameter less than 2.5 mm was associated with graft failure within 12 months after CABG.

Introduction. To develop new system modules of software to help employees with disabilities, it is required to work out an architectural solution for the interaction of all parts of the system. As a result of the analysis and design, it is necessary to obtain a software architecture that must meet a number of standard requirements. First of all, it should be safe. To do this, you should take into account the error logging system, event auditing, the possibility of disabling the functionality immediately after putting it into commercial operation, internal mechanisms for validating client input requests and server responses. This study is aimed at the development of basic system maintenance options, the analysis of exception cases under interacting with the user for further evaluation of the architecture efficiency, and the direct project development. Materials and Methods. The architectural decision was carried out using the Unified Modeling Language (UML), which helps to build visual images of the life cycle and interaction of all components of the system. The syntax of the UML deployment diagram was used to study the interaction of the main modules of the future system, and the syntax of the UML sequence diagram was used to process the lifecycle. A use case diagram was also applied to describe the main use cases. To study the interaction of the main modules of the future system, the UML deployment diagram syntax was used. For life cycle processing, the UML sequence diagram syntax was applied. In addition, a use case diagram was applied to describe the base use cases. Results. An architecture that has a scheme for the interaction of individual modules and systems, as well as options for using the software package for the future implementation of the software product, has been developed. The proposed system architecture meets the requirements of security, reliability (fault tolerance), and performance. The authors have fixed the functional requirements of the system of assistance to employees of enterprises with hearing problems for the possibility of their employment and work on the telecommunication Internet. Basic variations of system maintenance have been developed. Discussion and Conclusions. Building a competent architecture provides taking into account cases that go beyond the normal use of the system, and applying a fuzzy model to determine the system efficiency. Further in-depth description of deployment and operation options will enable to implement an efficient and productive system.

Modification of graphene electronic properties via contact with atoms of different kind allows for designing a number of functional post-silicon electronic devices. Specifically, 2D metallic layer formation over graphene is a promising approach to improving the electronic properties of graphene-based systems. In this work we analyse the electronic and spin structure of graphene synthesized on Pt(111) after sodium monolayer adsorption by means of angle-resolved photoemission spectroscopy and ab initio calculations. Here, we show that sodium layer formation leads to a shift of the graphene π states towards higher binding energies, but the most intriguing property of the studied system is the appearance of a partially spin-polarized Kanji symbol-like feature resembling the graphene Dirac cone in the electronic structure of adsorbed sodium. Our findings reveal that this structure is caused by a strong interaction between Na orbitals and Pt $$5d$$ spin-polarized states, where the graphene monolayer between them serves as a mediator of such interaction.

The induction installation for heating of the die equipment for a vertical hydraulic press with a force of 300 MN for stamping of aircraft drum wheels is considered. The regularities of the effect of temperature deformation regimes on the structure and mechanical properties of finished products in the technology for the production of aluminum 2014 alloy stampings are described. The results of metallographic control of mechanical properties, macrostructure, fracture structure and microstructure of stamping of an aviation drum wheel made of 2014 alloy are presented.