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Although antibiotics (AB) are ineffective for the treatment of COVID-19, they are often prescribed to patients with the novel coronavirus infection (NCV) for a variety of reasons. They include the difficulty of excluding bacterial co-infection at the first contact with the patient, as well as the possibility of developing a secondary bacterial infection. The aim of the work is to assess the frequency and background of prescribing antibiotics to hospitalized patients with confirmed COVID-19. Material and methods. A retrospective analysis of 160 hospital records of patients with confirmed COVID-19, who were treated in various Infectious Diseases Departments during the period from September to October 2020, was carried out. The selection was done by the method of random sampling. The analysis did not include the records of patients admitted to the ICU for NCV. Results. Information about the appointment of antibacterial drugs before hospitalization was found in 109 patients, of which only 51 patients did not receive AB on an outpatient basis. The remaining 58 (53.2%) patients began taking ABs on their own or based on the recommendation of an outpatient doctor, including 31 patients who took two or more drugs (successively or simultaneously). The most commonly used antibiotics were: macrolides (37 patients), cephalosporins (24 patients), respiratory fluoroquinolones (12 patients), and aminopenicillins (5 patients). On admission, AB was prescribed for almost all patients, except for one. The most frequently prescribed antibiotics were: macrolides (61%), mainly azithromycin, and respiratory fluoroquinolones (54.1%), mainly levofloxacin. In most cases, these drugs were combined with 3rd or 4th generation cephalosporins. Most patients received more than one AB: two drugs were prescribed to 86 (54.1%) patients, three — to 34 (21.4%) patients. AB therapy was carried out for a long time: the maximum number of days for macrolide administration (excluding previous AB therapy at the outpatient stage) was 16 days, respiratory fluoroquinolones — 22 days,3rd generation cephalosporins — 19 days,4th generation cephalosporins — 17 days, carbapenems — 34 days. In almost 100% of cases, ABs were prescribed on the first day of admission of patients, and their therapy continued until the patient was discharged from the hospital. Conclusion. The appointment of antibiotics at the hospital stage was established for the vast majority of patients in the absence of clear indications for their appointment. Such a frequent prescription of antibiotics is accompanied by a number of problems: immediate – side effects of such therapy (for example, antibiotic-associated diarrhea), long-term — an increase in antibiotic resistance of microorganisms.

The article shows the method of constructing the MMIC power limiter. The purpose of this research is to increase the burnout level. We considered a classical two-stage cir-cuit on anti-parallel p-i-n diodes. The idea of increasing the burnout level is to redis-tribute currents, so that at the burnout power at the first and second stages, the current is equal to the saturation current – 0.41–0.45 A / 100 µm. To do this, a simulation of the circuits was carried out – the ratio of the capacity of the first to the second stage 1:1, 2:1, 3:1 and 4:1. The design circuits were manufactured at p-i-n diode GaAs tech-nology of JSC RPC “Istok” named after Shokin, the height of the diode barrier is 1,1 V / 1 mA, the breakdown voltage is 45 V / 100 µA. The results of probe measurements S-parameters of power limiters and measure-ments of dynamic characteristics in the fix-ture are presented. Devices in the frequency range from 1 GHz to 16 GHz have losses less than 0.8 dB and VSWR input and output less than 2. The burnout level in continu-ous power at a frequency of 10 GHz was: for topology 1:1 — 45.3 dBm, 2:1 — 48.3 dBm and for topology 3:1 — 49.6 dBm. Under the same conditions, serial MMIC power limiters of foreign company were investigated. The burnout power density was ~20 W / 100 µm of the periphery, for the JSC RPC “Istok” named after Shokin technology, which exceeds the level of the investigated foreign analogues.

The article discusses the features of teaching clinical discipline (hospital therapy) in the special conditions of a pandemic, the possibility of combining full-time and distance learning, presents the experience of using distance technologies as an addition to traditional forms of teaching clinical discipline.

The article presents data on heart damage in patients with rheumatoid arthritis (RA), features of the development of ischemic and non-ischemic heart disease with a significant increase in the risk of adverse cardiovascular events. Patients with RA are characterized by an increased risk of developing myocardial infarction, heart failure, rhythm disturbances, sudden cardiac death, and general cardiovascular death. The possibility of a fairly rapid development of myocardial dysfunction in patients with RA from the moment of manifestation of the disease, the development and progression of atherosclerosis of the coronary arteries is emphasized, and with the development of coronary artery disease in RA patients, the worst survival rate after a heart attack was established. The available evidence suggests that rheumatoid arthritis is a disease that makes a significant contribution to cardiovascular morbidity and mortality.

The object of research in this work was cast iron for machine-building parts, alloyed with Al. The possibility of improving the mechanical properties of cast iron by choosing the optimal Mn – Al combinations, depending on the carbon content in the cast iron, was determined. The study was carried out on the basis of available retrospective data of serial industrial melts by constructing the regression equation for the ultimate strength of cast iron in the three-factor space of the input variables C – Mn – Al. The optimization problem was solved by the ridge analysis method after reducing the dimension of the factor space by fixing the carbon content at three levels: C = 3 %, C = 3.3 %, and C = 3.6 %. It was found that the maximum values of the ultimate strength are achieved at the minimum level of carbon content (C = 3%) and are in the range of values close to 300 MPa. In this case, the Al content is in the range (2.4–2.6) %, and the Mn content is about 0.82 %. With an increase in the carbon content, there is a tendency to a decrease in the content of Mn and Al in the alloy, which is necessary to ensure the ultimate strength close to 300 MPa. The results of the ridge analysis of the response surface also showed that at the upper limit of the carbon content (C = 3.6%), it is not possible to reach the ultimate strength of 300 MPa in the existing range of Mn and Al variation. All solutions are verified for the following ranges of input variables C = (2.94–3.66) %, Mn = (0.5–1.1) %, Al = (1.7–2.9) %. Graphical-analytical descriptions of the optimal Mn – Al ratios are obtained, depending on the actual content of carbon in the alloy, which make it possible to purposefully select the optimal melting modes by controlling the tensile strength of the alloy

Here, we represent the first review of the bat fauna of the large territory of Central Ukraine (to the west from Dnieper River). The review is based on results of the original survey in 1999–2021 and data from all available sources (publications, museum collections). Fauna of the region includes 24 bat species: Eptesicus, 2 species; Barbastella, 1; Myotis, 10; Nyctalus, 3; Pipistrellus, 4; Plecotus, 2; Vespertilio, 1; Rhinolophus, 1. For each species there is a short description of its distribution (illustrated by a map), used roosts, seasonality of presence and reproductive status within the study area. The bat fauna composition is analysed by three distinguished subregions, from north to south: of mixed forests, the forest-steppe, and the Dniester river. The estimation of prevalence and comparative abundance of the species in the region is given. The general review of bat roosts, by their types (under- and overground), seasonality of usage, and sheltered species is presented. The paper is supplemented with the extensive array of original, earlier unpublished, primary data on bat records in the region.

Currently, there is a lack of evidence for empiric use of antimicrobial agents in most patients with COVID-19 in outpatient and hospital settings as the overall proportion of secondary bacterial infections in COVID-19 is quite low. This literature review summarizes data on changes in antimicrobial resistance over the course of COVID-19 pandemic, especially in nosocomial ESKAPE pathogens. The other significant consequences of excessive and unnecessary administration of antibiotics to COVID-19 patients including risk of Clostridioides difficile infection and adverse effects of antimicrobial agents are also discussed.

Ground electrode cooling improved CO2 conversion in a DBD microreactor. A maximum in CO2 conversion of 10.6% was observed at a gas temperature of 363 K.

Experimental data are used in theoretical models to study the effects of input voltage and gas flow rate on plasma and background gas parameters in a voltage range where the transition from nondischarge to full-discharge happens. To this end, a specific methane-fed dielectric barrier discharge is used as a plasma reactor, and electrical modeling, the Boltzmann equation method, and emission spectrum analysis are employed to calculate plasma parameters and gas heating. The output of this study proves that a uniform plasma with a controllable background gas heating is achievable by the adjustment of input parameters such as voltage and gas flow rate in a well-designed dielectric barrier discharge.

Hydrogenation of CO2 is a promising way for CO2 utilization due to the possibility of producing a wide range of chemicals including CO, CH4, value-added hydrocarbons and oxygenates. Plasma technology, especially plasma-catalysis, has great potential for the valorisation of CO2 and has attracted much attention in recent years. The technological development in renewable energy and clean hydrogen production facilitates the research in plasma-assisted hydrogenation of CO2 as a green approach for chemical production and energy storage. As a result, there is growing interest in this field and a rapid increase in related research can be expected in the near future. Therefore, it is worthwhile to discuss the development of this technology along with current research gaps. This chapter presents a comprehensive review of research progress in plasma and plasma-catalytic CO2 hydrogenation with a focus on DBD plasma reactors and different catalysts. The status and potential challenges of CO2 methanation as well as the production of methanol and CO are covered. Both the plasma-induced gas phase and surface reaction pathways have been discussed to provide insights of the reaction mechanism. Finally, recommendations of potential directions for future research are given.

Mechanical and transport behavior of thin constrained layers has been an important area of research in solid mechanics. Emerging engineering applications, involving advanced materials, require one to model and analyze the response of thin layers in which mechanical and transport phenomena are coupled. Further, those thin layers are often integrated into larger complex systems, for which fundamental understanding is lacking. This gives rise to numerous challenging problems in applied mathematics, scientific computing, and modeling. We first analyze thin perfectly constrained linear elastic layers. A new asymptotic approach has been developed that, unlike all existing methods, does not invoke any assumptions other than the layer thinness and Saint-Venant's principle. Asymptotic solutions for the compressible and incompressible cases are relatively simple to construct, as they involve only one small parameter. However, these solutions are problematic for the nearly incompressible regime, which involves two small parameters. The problem is challenging both conceptually and in terms of matching accurate numerical solutions. Our approach closes the conceptual gaps, and is in excellent agreement with accurate numerical solutions across the entire physically admissible range of compressibilities. Next, we extend our asymptotic analysis to thin imperfectly constrained linear elastic layers. This problem is interesting due to the presence of interphases, whereby two additional small parameters are introduced. In particular, the interplay between up to four small parameters can significantly affect the mechanical response of thin constrained layers. Our new accurate asymptotic solution establishes conditions under which interphases associated with thin layers may be detected. Further, the solution for compressible layers leads to a new and remarkably simple experimental setup, which has yielded promising results. For thin linear chemo-elastic layers, we consider stress-assisted solid-state diffusion of solute through a deformable solid under isothermal conditions. We show that a thermodynamically-consistent characterization of stress-assisted diffusion should be in terms of the chemical potential, rather than the concentration, of the solute. Further, we formulate new thought experiments for measuring the chemo-elastic properties of solids. In particular, we propose a method for measuring the chemical potential of a solid, without imposing essential restrictions on its composition and external conditions. This enables the solid-state diffusion community to prescribe chemical potential boundary conditions, which as of yet is a non-intuitive task. Finally, we analyze a full-scale turning process involving a workpiece made of a difficult-to-machine advanced material. Lubrication was represented by varying the friction coefficient between the cutting tool and workpiece. Here we wanted to assess the existence of an anomalous trend observed experimentally by our project partners, whereby lubrication was less effective at certain cutting speeds. The extremely complex thermo-mechanical phenomena associated with this problem lead us to rely on a commercial finite element code for our simulations. Here our main challenge from the perspective of scientific computing was balancing available experimental data, computing resources, and accuracy of simulations.