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BACKGROUND: Platelet dysfunction in patients with COVID-19 is a well-known fact; however, its formation mechanisms remain unclear. AIM: To evaluate the role of oxidative stress in dysfunction of platelets in the patients with severe COVID-19-associated pneumonia. MATERIALS AND METHODS: The study has involved patients with COVID-19 (n = 27) aged 47 to 75 with more than 50% lung damage according to the chest multi-slice computed tomography. The control group has included healthy people comparable in sex and age (n = 24). All the patients have undergone evaluation of the number of platelets in blood, measurement of platelet aggregation induced by adenosine diphosphate, collagen, adrenaline and ristocetin and the level of lipid peroxidation and protein oxidative modifications products in platelet-rich plasma. The calculation and analysis of the obtained data has been carried out using the IBM SPSS Statistics v. 23. RESULTS: For the patients with severe COVID-19, a decrease in the number of platelets in the blood is characteristic. Acceleration of platelet aggregation induced by collagen and ristocetin has been observed on the 1st day, with the induction of adenosine diphosphate, collagen, adrenaline and ristocetin on the 8th day of the admission. Oxidative stress in COVID-19 leads to a significant increase in the level of primary markers of protein oxidative modifications in the platelets and an increase in the level of products of primary and secondary lipid peroxidation markers in the platelets. A direct correlation between the products of lipid peroxidation and protein oxidative modifications in the platelets and their aggregation has been found. CONCLUSIONS: The following study deepens the knowledge of the status of oxidative stress in SARS-CoV-2 infection, confirming its important role in the pathogenesis of COVID-19. The growth of protein oxidative modifications and lipid peroxidation products in patients with severe COVID-19-associated pneumonia in the course of the disease may be one of the causes of platelet dysfunction and, as a result, lead to lethal thrombotic complications.

BACKGROUND: Non-arteritic anterior ischemic optic neuropathy (NAION) takes the first place in the total amount of acute vascular optic neuropathy cases. There is no common understanding of pathogenetic mechanisms of disease. This is largely due to the absence of direct optic nerve head blood flow registration method in ophthalmology. AIM: The aim of this work is to evaluate ocular hemodynamics using different methods in patients with non-arteritic anterior ischemic optic neuropathy (NAION). MATERIALS AND METHODS: 73 patients were enrolled in the study. 46 patients (46 eyes) with NAION were included in the first group. Control group was composed of 27 patients (50 eyes) with systemic risk factors of NAION without any retinal and optic nerve diseases. Regional hemodynamics parameters were evaluated with ophthalmosphigmography, ophthalmoplethysmography, ophthalmoreography, OCT-angiography and EDI-OCT. RESULTS: Blood flow values in different parts of the choroid did not statistically differ between groups when using ophthalmosphigmography, ophthalmoplethysmography, ophthalmoreography methods. Radial peripapillary capillaries in optic nerve head area were evaluated, and statistically significant difference was found in all sectors. CONCLUSION: The main component of NAION pathogenesis is a decreasing perfusion pressure in paraoptic short posterior ciliary arteries. Blood flow in choroid does not play an important role in the disease pathogenesis.

The new coronavirus disease (COVID-19) is a viral respiratory infection accompanied by systemic endotheliitis. COVID-19 patients usually encounter changes related to hypercoagulability, hypofibrinolysis, and increased intravascular platelet aggregation. There is also a vascular wall thromboresistance decrease and impaired vasomotor function, which significantly increase the risk of thromboembolic complications. Currently, pathogenic aspects of the relationship between COVID-19 and vascular and inflammatory conditions of the optic nerve and retina are actively investigated. One of the triggers of impaired blood flow in ocular vessels may be a perfusion pressure decrease, observed in the acute period of the infectious process. This is related to both COVID-19 clinical course features and to resuscitation specificity as well. Secondary autoimmune inflammation is being considered as a mechanism of damage to the vascular wall in the post-infectious period. In this publication, possible pathogenic links of these diseases are considered for the first time in a specific context of the example of ischemic optic neuropathy associated with coronavirus infection.

В статье представлены результаты социологического исследования современного портрета буддийского паломника-онлайн Бурятии. В январе 2021 г. было опрошено 28 паломников, которые участвовали в буддийских ритуалах и учениях в онлайн-формате. Была произведена трехступенчатая выборка респондентов по критериям: место жительства — Бурятия; участие в реальных путешествиях к объектам поклонения; участие в виртуальном религиозном действе в онлайн-формате в период 2020–2021 гг. Буддист как паломник-онлайн Бурятии начала 2021 г. — это, по большей части, женщина от 40 до 60 лет, с высшим образованием, представитель непроизводственной сферы деятельности. Современный паломник-онлайн — буддист по традиции, он приобщен к буддизму с детства, большей частью пребывает в традиционном паломничестве, но, тем не менее, участвует и в виртуальном религиозном действии, например, в паломничестве к Учителям в режиме онлайн. Доход респондентов в основном — средний и ниже среднего. Представители этого социального среза буддистов Бурятии побывали в среднем в 2–3-х паломнических поездках (более 4-х раз в такие поездки отправлялись 57,1% респондентов), а в их планах на будущее — еще не менее 4-х таковых. Состав опрошенных преимущественно женский — 92,9%. Причем среди такой категории людей особо можно выделить возрастной период — от 55 до 60 лет. Они продолжают планировать новые поездки. Монголия, Индия и Тибет являются наиболее важными направлениями, которые паломники выбирают обязательно помимо Бурятии.

We investigated room-temperature pulsed lasing in heavily doped Fe:ZnSe single crystals. The active elements were pumped by a Q-switched Cr3+:Yb3+:Ho3+:YSGG laser operating at 2.87 μm. Our results show that the generation of short laser pulses has a deep high-frequency modulation associated with relaxation dynamics in Fe:ZnSe. The lasing regime obtained in this study provides a straightforward way to generate mid-IR single nanosecond pulses at moderate pump energies. Moreover, we found a relation between the lasing pulse duration and the concentration of Fe2+ doping ions, and we experimentally demonstrated pulse shortening in heavily doped active crystals. Single-pulse lasing with an FWHM pulse duration of ~2.8 ns was achieved in ZnSe crystals doped with 2.3 · 1019 cm-3 Fe2+ ions. The demonstrated single-pulse lasing regime is applicable for seeding high-power mid-IR laser systems.

The article discusses the problems of the development of the modern Buryat language in the Republic of Buryatia. It gives a brief analysis of the outcomes of this development in the approximately thirty years from the establishment of the legal status of the Buryat language as an official language in the republic. The study points out the problems, controversial points in the process of Buryat language becoming official. It gives the meaning of functional isomorphism in this process. The authors give the specific results and recommendations for the constructive expansion of the functional opportunities of the Buryat language.

The actual applied problems of modern pedagogy of higher education include the processes of educa-tional adaptation of participants in educational rela-tions “lecturer-listener”, as well as pedagogical im-provement of teachers-lecturers of higher education institutions. The authors raise the issue in the con-text of developing both classroom and online lec-tures on the discipline "philosophy of ethnos" for postgraduates. The article examines the role and significance of ethnophilosophical knowledge for the formation of such universal competencies as critical analysis or generating new ideas in science. The peculiarities of pedagogical interaction between the lecturer and students, of course, ensure the suc-cess of the teaching process. Using the example of observations made by one of the authors of the arti-cle at the faculty of philosophy, we describe such key characteristics of lectures by leading Russian philosophers as the identification of the problem field, discussion and interactivity. In the conclu-sions, the applied aspect of lecturer’s didactic and pedagogical skills in shaping the generic competen-cies of graduate students regarding the need to fo-cus the audience's attention through modulation in the intonations and articulations on relevant con-cepts, judgments, conclusions is highlighted. The skills of setting the problem field of learning and understanding the audience of the topic, posing the issues for students to motivate them for analytical and comparative mental operations and acting as a communicative leader, contributing to interactive lectures are also noted.

The a.c. Josephson effect predicted in 1962

Memristors are expected to form a major cornerstone in the upcoming renaissance of analog computing, owing to their very small spatial footprint and low power consumption. Due to the nature of their structure and operation, the response of a memristor is intrinsically tied to local variabilities in the device. This characteristic is amplified by currently employed semiconductor fabrication processes, which introduce spatial inhomogeneities into the structural fabric that makes up the layers of memristors. In this work, we propose a novel q-deformed current-voltage model for memristors based on the superstatistics framework, which allows the description of system-level responses while taking local variabilities into account. Applied on a Ag-Cu based synaptic memory cell, we demonstrate that our model has a 4-14% lower error than currently used models. Additionally, we show how the resulting q-parameter can be used to make statements about the internal makeup of the memristor, giving insights to spatial inhomogeneities and quality control., Comment: 11 pages, 6 figures, appendix

We study operation of a superconducting quantum interference devices (SQUIDs) based on a new bilayer material. They can be used for the ultra-sensitive detection of magnetic momentum at temperatures down to milliKelvin range. Typically, thermal origin hysteresis of the symmetric SQUID current-voltage curves limits operating temperatures to T>0.6Tc. We used a new bilayer material for SQUID fabrication, namely proximity-coupled superconductor/normal-metal (S/N) bilayers (aluminum 25 nm/platinum 5 nm). Because of the 5 nm Pt-layer, Al/Pt devices show nonhysteretic behavior in a broad temperature range from 20 mK to 0.8 K. Furthermore, the Al/Pt bilayer devices demonstrate an order of magnitude lower critical current compared to the Al devices, which decreases the screening parameter (βL) and improves the modulation depth of the critical current by magnetic flux. Operation at lower temperatures reduces thermal noise and increases the SQUID magnetic field resolution. Moreover, we expect strong decrease of two-level fluctuators on the surface of aluminum due to Pt-layer oxidation protection and hence significant reduction of the 1/f noise. Optimized geometry of Al/Pt symmetric SQUIDs is promising for the detection of single-electron spin flip.

In this article, a clinical case of astrocytoma of optic nerve head in patient with neurofibromatosis type 1 is presented. The main feature of this clinical case is a difficulty in differential diagnosis with amelanotic choroidal melanoma.

The work is devoted to the study of the impact of virtual objects in virtual, augmented and mixed reality systems on the quality of human visual perception. The features of the operation of virtual, augmented and mixed reality systems, the principles of image formation of the virtual and real worlds and the problems of their combination are described. For mixed reality systems, the basic principles of building systems, their specifics and the principles of forming an image of the real world are described. The specific reasons for the formation of the conflict of visual perception in mixed reality systems are considered. There are three main causes of conflict that can be overcome in modern mixed reality systems: the position and type of the light source; the correct formation of shadows from virtual sources on the image of real-world objects; and the intensity of radiation, including the radiation diagram. A method for evaluating the correctness of the formation of illumination of virtual objects in a mixed reality system and its influence on the quality of visual perception is proposed. To evaluate the proposed methodology, a number of test scenes with correct and incorrect lighting of virtual objects have been developed. The assessment of the quality of visual perception was carried out on a test group of 24 people with experience in computer graphics systems. The quality was evaluated on a good/bad scale. Based on the results of the expert assessment, a conclusion was formed that defines the requirement for building a lighting system for virtual objects in mixed reality systems.

Plasmonic metasurfaces form a convenient platform for light manipulation at the nanoscale due to their specific localized surface plasmons. Even despite high intrinsic Joule losses, plasmonic nanoparticles are very effective for light manipulation. Here, we show the lattice of plasmonic nanoparticles onto a dielectric waveguide that efficiently couples oppositely propagating guided modes to circularly polarized light beams of different handedness. We demonstrate 80% degree of circular polarization for the out-coupled emission of GaAs-waveguide-embedded quantum dots. The results allow us to consider the lattice as a circular-polarization-controlled grating coupler and make this structure prospective for further implementation as an efficient coupling interface for integrated devices.

Purpose. doctrinal and statutory analysis of the essence of an investigatory examination aimed at identification of theoretical, legislative and applied issues arising in the course of acknowledging objects or documents as material evidence in a criminal case and elaboration of ways and means of their elimination and solution. Methodology: dialectics, analysis, synthesis, historical and legal method, system research method. Conclusions. 1) The scientific doctrine and the criminal procedure laws based on it combine two various forms of cognition of criminal case circumstances: a) an examination as a non-verbal investigatory action aimed at visual and graphic perception of material fragments of objective reality and b) further research of such fragments accompanied by formal and logical thinking and ending with coming to specific conclusions. 2) Primarily, an investigator has to attempt not at an examination of an object or a document rather at its safekeeping within a criminal case, ensuring an opportunity of its further research in the original state, in particular, in a court hearing. 3) An examination as a standalone investigatory action is an excess link in the mechanism of acknowledging objects or documents as material evidence stipulated by Part 2 Article 81 of the Criminal Procedure Code of the Russian Federation except for the cases when it is impossible to ensure their safekeeping up to the termination of the criminal case proceedings. Scientific and practical significance. The conducted research may be useful for scientists, students, postgraduate students and junior scientific assistants, practitioners and everyone interested in the issues of the investigatory action carrying out.

In the paper, the finite groups G are studied for which every invariant subgroup A has the property that |G: AC G (A)| divides a fixed prime p.

Background: Lung diseases are assuming greater relevance and importance today. Chronic bronchitis is a self-nosology, which may precede the development of COPD, the importance of which can hardly be overestimated. The main problem in this disease is caused by late diagnosis and treatment due to the delay by patients in seeking medical help. The aim of the work was to study the distribution and exposure to tobacco smoke, especially chronic bronchitis, depending on various factors, including age. Methods: We examined 1779 persons, including 855 men and 924 women. The mean age of the population was 35.83±8.3 years. We conducted surveys and spirometry. The outcome was assessed after a bronchodilation test was performed with salbutamol 400 mcg. We performed all statistical analysis using software package Statistica 10. Results: We identified chronic bronchitis in 9.2% of the cases in the group of younger individuals and in 14.9% of the cases in the group of older individuals, during the active detection of chronic bronchitis using questionnaires. The prevalence of cigarette smoking was slightly higher among the younger (39.5%) than the older persons (33.6%); the frequency of smoking in a group of chronic bronchitis was reliably higher. Also, in this group, the performance spirometry reliably decreased. Conclusions: Outpatient survey is an effective method of identifying chronic bronchitis. Smoking is a major risk factor in the group of young respondents and the prevalence of smoking is inversely related to the education level of the respondents, regardless of age. As the decline in the Forced Expiratory Volume (FEV1 and FEV1/FVC) is the main criterion diagnosis of COPD, it revealed significant declines in the FEV1 of the younger smoking individuals, which may help to predict the development of COPD in the older age group.

The results of > experiment with quasispherical Laser-produced Plasma Clouds (LPC) expanding into strong (B{sub 0} {approx}10 kG) and uniform magnetic field at KI-1 facility of ILP are presented. Main characteristics and the influence of non-MHD flute instability onto effectiveness of plasma-field interaction were studied especially for the purpose of plasma confinement and the direct conversion of its kinetic energy into magnetic and electric ones (of pick-up coils). A new model of enhanced field penetration into plasma due to Hall-effect in its flutes and under conditions of finite ion Larmor radius is discussed. The data obtained on the current generation by LPC in short-circuited surrounding coils (with total conversion efficiency up to {approx}10%) are compared with the models of ILP and last results of relevant 3D/PIC calculations done at KU. All these results show the opportunities of LPC-experiments to simulate both space exploding plasmas (AMPTE) and MHD-effects of ICF micro-explosions in planned NIF experiments for study Laser Fusion Rocket like a VISTA.

Denote by w(n) the number of factors in a representation of a positive integer n as a product of primes. If H is a subgroup of a finite group G, then we set \(w(H) = w(|H|)\) and \(v(G) = {\text{max\{ }}w(C(g))|g \in G\backslash Z(G)\} \). In the present paper we present the complete description of groups with nontrivial center that satisfy the condition \(v(G) = 4\).

On the basis of a simple model of Czochralski crystal growth method, a theoretical analysis of crystal-meniscus system behaviour has been carried out. It has been shown that in a finite radius crucible, mutual influence of crystal radius and meniscus height leads to the possibility of their autooscillation. The dependence of autooscillation characteristics on crystal growth model parameters has been analysed. It has been shown that the amplitude of autooscillations decreases with the increase of crystal radius/crucible radius ratio. Numerical estimations for LEC GaAs crystal growth have been made. The problems of crystal radius control in this connection are discussed.

Denote by w(n) the number of factors in the representation of a positive integer n in the form of a product of primes. For a subgroup >H of a finite group G, we set w(H)=w(|H|) and v(G)= maxw(C(g))| g ∈ G \ Z(G). In the present paper, the complete description of centerfree groups satisfying the condition v(G)= 4 is presented.

The main result of this paper is: any primary Arguesian lattice over the field GF(p) of geometric dimension at least three is isomorphic to the lattice of all submodules of a finitely generated module over the ring of polynomials of bounded degree over the field GF(p).

[No abstract available]

the range up to 1 nm it can provide short-time sources ofradiation in the form of a few lines and with efficiency -4%. The charge-transfer pumping has two main advantages: itpopulates preferentially the lasing level of ions due to its quasi-resonant character and, principally, there is a possibility topump all laser-produced ions. In the experiments by Dixon R.H. and Elton R.C. [2] with laser-produced plasma expandinginto background gas an inversion of population for various ions has been demonstrated. The levels of preferential populationwell accorded to ones predicted by charge-transfer mechanism. Nevertheless, this inversion didn't show the influence fromgas pressure nor from the sort of gas, and the efficiency of the process was no more than 1 0 of maximum possible valuefor the given densities of ions and neutrals. The reason of such low efficiency has been clarified in other experiments (forexample [3]) and especially in numerical simulations [4]. At first millimeters from the surface of plasma production thebackground gas is very rapidly ionized by photons and hot electrons. When the temperature of plasma falls down due toadiabatic expansion then another process switches on