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Non-oxidative methane coupling in an atmospheric pressure plasma jet reactor with an internal diameter of 3.0 mm has been studied. The jet reactor consisted of a quartz tube surrounded by a copper ring and a stainless-steel tube, which were separated by a variable distance. The stainless-steel tube (inner diameter: 1.0 mm, outer diameter: 1.5 mm) served as high voltage electrode and gas inlet. The jet characteristics with different tip angles of the high voltage electrode were investigated using voltage–current waveforms and gas analysis at a constant methane flow rate of 100 ml min−1. The effect of the length of the ground electrode and the gap between the electrodes on conversion, C2 selectivity and energy efficiency has been studied. The methane conversion was nearly tripled with a sharp angle of the electrode (15°), while the energy consumption was reduced from 150 to 55 kJ molC2Hy−1. The carbon deposition was also reduced.

Diagnosing bacterial infection in patients with novel coronavirus infection (COVID-19) is not an easy task. Available data suggest that bacterial infection in patients with COVID-19 is rare and occurs in less than 10% of cases. At the same time, data of individual studies and systematic reviews indicate that more than 70% of patients with COVID-19 receive mainly empirical antimicrobial therapy with broad-spectrum antibiotics often before the diagnosis of COVID-19 has been verified. Therefore, this widespread empirical use of antibiotics is not supported by data on the need for their use.The article discusses the literature data on the significance of commonly accepted methods for diagnosing bacterial infection, with an emphasis on laboratory presence / absence tests. In everyday practice, the likelihood of bacterial coinfection in patients with COVID-19 is assessed by clinical presentation of the disease and the results of standard laboratory tests and imaging methods. However, when viral respiratory infection develops, this approach does not always allow to diagnose bacterial coinfection with sufficient significance. This issue may be handled by available modern test systems, the use of a combination of signs or additional laboratory criteria (for example, procalcitonin), and the analysis of the overall clinical presentation by the doctor using knowledge about patient risk groups.

An increase in the number of images and their average size is the general trend nowadays. This increase leads to certain problems with data storage and transfer via communication lines. A common way to solve this problem is to apply lossy compression that provides sufficiently larger compression ratios compared to lossless compression approaches. However, lossy compression has several peculiarities, especially if a compressed image is corrupted by quite intensive noise. First, a specific noise-filtering effect is observed. Second, an optimal operational point (OOP) might exist where the quality of a compressed image is closer to the corresponding noise-free image than the quality of the original image according to a chosen quality metric. In this case, it is worth compressing this image in the OOP or its closest neighborhood. These peculiarities have been earlier studied and their positive impact on image quality improvement has been demonstrated. Filtering of noisy images due to lossy compression is not perfect. Because of this, it is worth checking can additional quality improvement be reached using such an approach as post-filtering. In this study, we attempt to answer the questions: “is it worth to post-filter an image after lossy compression, especially in OOP’s neighborhood? And what benefit can it bring in the sense of image quality?”. The study is carried out for better portable graphics (BPG) coder and the DCT-based filter focusing mainly on one-component (grayscale) images. The quality of images is characterized by several metrics such as PSNR, PSNR-HVS-M, and FSIM. Possible image quality increasing via post-filtering is demonstrated and the recommendations for filter parameter setting are given.

The first human cases of new coronavirus (COVID-19), for the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), were in Wuhan, in December 2019. By June 2022 there had been more than 500 million with confirmed cases of new coronavirus and over 5 million lives lost to the disease. During the earlier SARS-CoV-1 and MERSCoV epidemics, patients often developed bacterial coinfections and had a higher mortality rate. The aim of this work is to summarize the results of a study of the frequency and nature of bacterial infection in patients with COVID-19. Various studies was been in USA and countries of Asia and Europe show conflicting results regarding the prevalence of secondary bacterial infections in patients with COVID-19, from 1% to 50%. Bacterial co-infection is relatively infrequent in hospitalized patients with COVID-19. Risk factors of bacterial infections in patients with COVID-19 are more 60 years old, prolonged hospital length of stay, reanimation unit admission (severe disease COVID-19), chronic bacterial infection in anamnesis, immunosuppression therapy. The most common bacterial microorganisms identified in patients with infection of the lower respiratory tract, who hospital length of stay less than 48 hours are Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae. In patients, who hospital length of stay more than 48 hours the main pathogens are P. aeruginosa, Klebsiella spp., S. aureus. The data obtained indicate a low frequency of bacterial infections in patients hospitalized for COVID-19. Early infections are quite rare, more often bacterial infections are secondary and develop after 48 hours of the patient's stay in the hospital. The causative agents of early and late infections are different. Most often, an infection of the respiratory tract is noted, less often — the urinary system and bacterial infections of other localization.

The article discusses the concept and educational role of the clinical conference in the preparation of residents of therapeutic specialties at the Department of Hospital Therapy. The purpose of holding a clinical conference of residents is to improve professional and universal competencies and develop clinical thinking in future therapists in the process of teaching hospital therapy. The authors consider the clinical conference as an effective form of educational process that combines students' independent activities, interaction with the teacher, and the formation of basic skills for future medical practice.

The article presents an analytical approach to the implementation of ballasting and dual tires using of agricultural wheeled tractors, which is based on the unconditional fulfilment of agro-ecological standards of tires soil interaction. The necessity of harmonizing the indicators of the position of the centre of gravity of the tractor, the footprint area of the front and rear tires ratio, as well as their load capacity is shown. The need to use equal flotation in tractor’s tires during single and double use has been proven, which determines the need to maintain the position of the centre of gravity during ballasting. The method of selecting the mass of ballast weights for installation in the rear wheel discs and the front linkage system of the tractor, as well as the ballast weight system, which makes it possible to ensure the maximum possible weight of the tractor to meet the agro-ecological requirements regarding the maximum pressure on the soil, is proposed. The perspective of dual tires using to reduce the maximum pressure of the tractor on the soil is shown, and the high efficiency of ballasting the tractor on dual tires is also proven. The example shows the possibility of increasing the part of the territory of Ukraine where it is possible to operate the tractor without violating agro-ecological norms by 20-40% due to the use of dual tires. The possibility of increasing the efficiency of the tractor up to 1.5 times due to ballasting and doubling of tires has also been proven. The obtained data are based on 20 calculation variants of the tractor with different degrees of ballasting and the use of different tire doubling schemes.

In the work, the unevenness of the translational speed of a crawler with a triangular outline shape and the upper location of the drive wheel is analyzed. It was established that the value of the motion unevenness coefficient is a function of the design parameters of the engine. Of all these parameters, only the height of the location of the driving wheel practically cannot be changed, since it is determined by the dimensions of the tire in the wheel modification. Other structural parameters can change during the development of the engine design and, therefore, be the controlling elements in the system, which causes the unevenness of the translational speed.

A mechanism for forming a strategic program for the development of the production process of a car service enterprise has been developed. The factors of the external and internal environment that influence the component parts of the program and determine its content are determined. The conditions and procedure for analysis of the state of production and planning, development of a program for the development of the production process are given. The mechanism of formation, implementation of the development program, improvement of the production process and evaluation of its effectiveness has been developed.

The article provides an evaluative analysis of the wheeled agricultural tractor’s running systems soil interaction. A sample of more than 600 MFWD tractors of the world's leading manufacturers was subject to analysis. To determine the parameters of the maximum soil pressure, the value of the footprint gross flat plate area is applied, assuming that the tires are operated under conditions characterized by the speed index A6 with a significant torque for a long time. It is obtained the calculated function of the probability distribution of the maximum pressure on the soil of a sample of modern wheeled tractors with a fixed location of the centre of gravity (weight distribution). The designed arrangement of the centre of gravity of tractors by groups with the corresponding rolling circumference indexes difference ΔRCI =4...9 was analysed. It was established that for general and universal purpose tractors with ΔRCI = 4...6 the most common weight distribution coefficient is 0.40 or 0.44. For special (utility) tractors with ΔRCI = 7...9, the most common weight distribution coefficient is 0.45...0.46. An analysis of the maximum soil pressure in a wide range of the traction force of the tractor while maintaining a constant optimal weight distribution, which depends on the ratio of the footprint gross flat plate area of the front and rear tires, was carried out. The analysis showed that maintaining a constant optimal weight distribution during traction operations makes it possible to reduce the maximum pressure on the soil by 8...40 kPa. This makes it possible to increase the part of the territory of Ukraine, where modern wheeled tractors with single tires can be operated without violating agro-ecological requirements, by 14%.

Over the past two years, the SARS-CoV-2 pandemic has dominated all aspects of health care around the world, often leaving other long-term public health problems in the background. Despite the fact that COVID-19 is a viral disease, the use of antibiotics in these patients was common practice, especially at the beginning of the pandemic. The use of antibiotics (ABs) in patients with the novel coronavirus infection (NCI) reaches over 70% cases. Suspected concomitant bacterial infection, lack of effective means of treating NCI, terminological problems associated with the definition of «pneumonia» may have been the motivating factor for such widespread use. The data of the conducted studies indicate that there is currently insufficient evidence for the widespread empirical use of antibiotics in the majority of hospitalized patients, as the total proportion of bacterial infections in COVID-19 is quite low. Thus, according to most researchers, combined bacterial infection is rare and is less than 10%. Unjustified prescription of ABs to patients with COVID-19 can lead to complications that could otherwise have been avoided, including increased bacterial resistance, Clostridioides difficile infection, kidney failure, and much more. The article provides information on the frequency of AB therapy at various stages of medical care. The analysis of data on the nature of antibiotics prescribed to inpatients and outpatients with COVID-19 in different countries was carried out. Recommendations from different countries on AB therapy in patients with COVID-19 are presented. Conclusion. The data reviewed confirm the discrepancy between the unjustified and excessive prescribing of antibiotics to patients with COVID-19 and the small number of evidence of associated bacterial infections.

Introduction. The production of NaI-based single crystals results in accumulation of great amount of liquid waste. To bring valuable constituents of this waste back, the NaI technogenic solutions are treated to precipitate iodine that is further used in the synthesis of high-pure NaI. However, the least contaminated part of the waste may be brought back into the main technological process without the intermediary stage of iodine destruction, which allows a considerable cost saving.Problem Statement. There have been no data on the effective purification coefficients for NaI solutions subsequently treated with barium hydroxide, sodium carbonate, and by mass crystallization. Requirements to impurity content, which NaI solutions have to comply with in order to be used in the nondestructive treatment have mot been not formulated.Purpose. The purpose of this research is to develop a technology for reprocessing NaI technogenic solutionsinto sodium iodide of high purity without NaI destruction at the intermediate stage.Material and Methods. The materials that have been used for this research are as follows: aqueous solutions of NaI-based crystal production waste, active coal, barium hydroxide, sodium carbonate. The methods that have been employed are the treatment of NaI solutions with barium hydroxide, sodium carbonate, and by mass crystallization. Results. The technology of NaI solution purification by treatment with barium hydroxide and sodium carbonate with further mass crystallization of the purified salt has been developed. This technology is more environment friendly and cheaper than the conventional one that includes obtaining pure iodine. A series of NaI technogenic solutions has been treated in laboratory conditions and on industrial equipment, and the efficiency of their purification by the chemical treatment and mass crystallization hasbeen estimated. The impurity content in the obtained salt and the scintillation parameters of grown NaI : Tl crystals meet the requirements for these products.Conclusions. The technology has been implemented in the manufacturing process at the pilot plant of the Institute for Scintillation Materials of the NAS of Ukraine. It may be used at other enterprises that deal with alkali metal iodide waste treatment.

BACKGROUND. There is enough evidence of the negative impact of excess weight on the formation and progression of res piratory pathology. Given the continuing SARS-CoV-2 pandemic, it is relevant to determine the relationship between body mass index (BMI) and the clinical features of the novel coronavirus infection (NCI).AIM. To study the effect of BMI on the course of the acute SARS-COV-2 infection and the post-covid period.MATERIALS AND METHODS. AKTIV and AKTIV 2 are multicenter non-interventional real-world registers. The АКТИВ registry (n=6396) includes non-overlapping outpatient and inpatient arms with 6 visits in each. The АКТИВ 2 registry (n=2968) collected the data of hospitalized patients and included 3 visits. All subjects were divided into 3 groups: not overweight (n=2139), overweight (n=2931) and obese (n=2666).RESULTS. A higher BMI was significantly associated with a more severe course of the infection in the form of acute kidney injury (p=0.018), cytokine storm (pCONCLUSION. Overweight and/or obesity is a significant risk factor for severe course of the new coronavirus infection and the associated cardiovascular and kidney damage Overweight people and patients with the 1st and 2nd degree obesity tend to have a high risk of death of SARS-CoV-2 infection in both acute and post-covid periods. On top of that, in case of morbid obesity patients this tendency is statistically significant. Normalization of body weight is a strategic objective of modern medicine and can contribute to prevention of respiratory conditions, severe course and complications of the new coronavirus infection.

Purpose of the study – to study the efficacy and safety of tenoxicam (Texared®) in patients with active axial spondyloarthritis.Material and methods. The study included 35 patients with active axial spondyloarthritis with BASDAI≥4.0. Patients were given continuous oral tenoxicam (Texared®, Dr. Reddy’s Laboratories) at a dosage of 20 mg/day. Subsequently, 5 patients were excluded from the study due to discontinuation of the drug after 5–10 days of administration. 30 patients were included in the final analysis. Initially and after 30 days, to assess the severity of pain and stiffness, activity, patients filled out questionnaires in electronic form using Google forms, a general assessment of pain in the lower back and the intensity of night pain by the patient, subjective sleep characteristics were carried out. The doctor calculated the BASDAI, ASDAS-CRP, BASMI indices, and evaluated the activity according to the doctor’s opinion. The baseline blood pressure level was determined, and a patient diary was issued for ambulatory blood pressure measurement in the morning/evening for 30 days. After 30 days, the patient’s ambulatory blood pressure control was assessed. At baseline and after 30 days, biochemical blood parameters were studied, including a complete blood and urine test.Results and conclusion. In patients with axial spondyloarthritis with high and very high activity, a positive effect of tenoxicam (Texared®) therapy on disease activity was noted. The effect of Texared® develops with regular use already during the first 2 weeks, and after 4 weeks there is a clear decrease in the severity of pain in the lower back, a decrease in the duration of morning stiffness. The drug is well tolerated, has a favorable safety profile, no serious adverse events and few side effects that do not require discontinuation of therapy.

Purpose of the study. To study the frequency and structure of postcovid syndrome (PCS) in patients with rheumatic diseases (RD).Materials and methods. The study included 70 patients with RD who had a coronavirus infection during the year. A questionnaire was carried out on the severity of the coronavirus infection, persisting symptoms in the postcovid period. Questionnaires of anxiety and depression, sleep quality were used, the activity of RD was assessed.Results. Manifestations of PCS occurred in 50 (71 %) patients, of which 47 (67 %) had 2 or more manifestations. PCS was observed equally often in patients with different severity of infection. Such the symptoms of PCS as weakness, arthralgia, increased blood pressure, shortness of breath, tachycardia prevailed during 3 months after COVID-19. Half of the patients had a decrease in the severity of weakness, arthralgia and shortness of breath after 6 months, but the destabilization of blood pressure and tachycardia remained at the same level. Such the psychoemotional manifestations of PCS as moderate depression, memory impairment, insomnia were observed.Conclusions. More than 2/3 of patients with RS who have undergone COVID-19 are faced with PKS. In 1/3 of the examined patients with RD the duration of the persistence of symptoms of PCS exceeds 6 months after infection. After revealing of blood pressure destabilization in patients with rheumatic diseases, it is advisable to assess cardiovascular risks in patients who have undergone COVID-19.

The analysis of alternative decisions and the choice of the optimal – in a given sense – decision is an integral part of people’s purposeful activity in all areas of their social life. Many formal approaches have been proposed to solve these problems. One such approach is expected utility theory, which correctly models individuals’ subjective preferences and attitudes to risk. For a very long time this theory was the leading approach for decision making under conditions of risk. However, numerous practical studies have shown its weakness: the theory did not explicitly use subjective perceptions of decision outcome probabilities in optimal decision-making processes. This research has led to the creation and development of approaches to explicitly consider the probabilities of outcomes in decision making. This paper provides a critical analysis of the descriptive properties of expected utility theory and presents various forms of probability weighting functions.

Minimally invasive percutaneous techniques, staged as part of the combined treatment of high stricture complications of the biliary tract, demonstrated high efficiency in the short term. On the other hand, the use of self-expanding nitinol stents as a definitive treatment for non-tumor stricture of the biliary tract in long-term life prognosis cannot be recommended as a routine intervention. The use of stents in these cases can only be justified in the absence of alternative treatment options, subject to frequent monitoring of the biliary tract.

Catalysis science and technology increased efforts recently to progress beyond conventional "thermal" catalysis and face the challenges of net-zero emissions and electrification of production. Nevertheless, a better gaps and opportunities analysis is necessary. This review analyses four emerging areas of unconventional or less-conventional catalysis which share the common aspect of using directly renewable energy sources: (i) plasma catalysis, (ii) catalysis for flow chemistry and process intensification, (iii) application of electromagnetic (EM) fields to modulate catalytic activity and (iv) nanoscale generation at the catalyst interface of a strong local EM by plasmonic effect. Plasma catalysis has demonstrated synergistic effects, where the outcome is higher than the sum of both processes alone. Still, the underlying mechanisms are complex, and synergy is not always obtained. There is a crucial need for a better understanding to (i) design catalysts tailored to the plasma environment, (ii) design plasma reactors with optimal transport of plasma species to the catalyst surface, and (iii) tune the plasma conditions so they work in optimal synergy with the catalyst. Microfluidic reactors (flow chemistry) is another emerging sector leading to the intensification of catalytic syntheses, particularly in organic chemistry. New unconventional catalysts must be designed to exploit in full the novel possibilities. With a focus on (a) continuous-flow photocatalysis, (b) electrochemical flow catalysis, (c) microwave flow catalysis and (d) ultrasound flow activation, a series of examples are discussed, with also indications on scale-up and process industrialisation. The third area discussed regards the effect on catalytic performances of applying oriented EM fields spanning several orders of magnitude. Under well-defined conditions, gas breakdown and, in some cases, plasma formation generates activated gas phase species. The EM field-driven chemical conversion processes depend further on structured electric/magnetic catalysts, which shape the EM field in strength and direction. Different effects influencing chemical conversion have been reported, including reduced activation energy, surface charging, hot spot generation, and selective local heating. The last topic discussed is complementary to the third, focusing on the possibility of tuning the photo- and electro-catalytic properties by creating a strong localised electrical field with a plasmonic effect. The novel possibilities of hot carriers generated by the plasmonic effect are also discussed. This review thus aims to stimulate the reader to make new, creative catalysis to address the challenges of reaching a carbon-neutral world.

Vector method for scanning with focused beam of megaelectronvolt-energy in proton-beam writing is described. Vector proton-beam writing method was proven experimentally to have numerous advantages over raster method. Focused beam size and shape are measured by scanning standard copper mesh for e-beam microscopy. Prospectives of hardware and software upgrade are regarded. Vector proton-beam writing technology can be used in many applications, including X-ray optics, electronics prototyping, microrobotics, microfluidics, photonics and microstructure fabrication in new materials.

Background. According to the scientific literature, anti-CD74 IgA antibodies (IgA anti-CD74) are considered as a possible marker for the diagnosis of axial spondyloarthritis (SpA). The level of IgA anti-CD74 in patients with back pain due to degenerative spine disease has not been studied. Therefore, it could be interesting to compare the serum levels of IgA anti-CD74 in patients with chronic back pain in various diseases. Aim: to compare the levels of IgA anti-CD74 in patients with SpA and degenerative spine diseases. Material and methods. A total of 87 SpA patients (55 male, mean age 41 [29; 49] years) fulfilling the Assessment of Spondyloarthritis International Society (2009) criteria for Axial SpA, and 39 patients (25 male, mean age 45 [34; 53] years) with neurologist-verified degenerative spine diseases (ICD 10 codes — M 51.1 and M 54.4) were enrolled to the study. The serum levels of IgA anti-CD74 were analyzed by enzyme-linked immunosorbent assay (ELISA) in all patients. Results. The median levels of IgA anti-CD74 in patients with SpA were 11.3 [5.4; 19.4] U/ml, in patients with degenerative spine disease — 6.9 [4.5; 13.7] U/ml (p=0.024). IgA anti-CD74 serum levels were above the cut-off value in 58 (66.7 %) patients with SpA and only in 11 (28.2 %) patients with degenerative spine disease (p< 0,001). The elevated serum levels of IgA anti-CD74 were detected in 10 (40 %) of 25 male patients and in 1 (7.1 %) of 14 female patients (p = 0.029, χ2 = 4.785) with degenerative spine disease. Conclusion. Serum levels of I gA anti-CD74 were increased in two-thirds of patients with SpA. IgA anti-CD74 was significantly higher in SpA patients compared to patients with degenerative spine disease.

Aim. To assess the relationship between the activity of systemic inflammation and the hemoglobin level in patients with spondyloarthritis (SpA).Materials and methods. We examined 92 patients with SpA aged 42.9 ± 11.6 years (SpA duration – 14.8 ± 9.6 years, 55 (60%) men). We calculated the BASDAI and ASDAS-CRP scores, performed complete blood count, evaluated erythrocyte sedimentation rate (ESR), ferrokinetic parameters, C-reactive protein (CRP) level, and serum concentrations of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6).Results. Anemia was found in 52 (57%) patients: 13 (25%) patients were diagnosed with anemia of inflammation (AI), 39 (75%) individuals had a combination of AI and iron deficiency anemia. A significant increase in CRP (17.8 vs. 9.0 mg / l, respectively; p = 0.001) and ESR (23 vs. 10 mm / h, p < 0.001), a tendency toward an increase in IL-6 levels (5.4 vs. 4.1 pg / ml, p = 0.051), and no difference in TNF-α levels (3.4 vs. 3.0 pg / ml, p = 0.245) were revealed in patients with anemia compared with patients with normal hemoglobin level. The hemoglobin concentration was negatively correlated with the CRP level (r = –0.327, p = 0.001) and ESR (r = –0.527, p < 0.001). IL-6 was positively correlated with the levels of TNF-a, CRP, and ESR (r = 0.431, r = 0.361, r = 0.369; all p < 0.001). With the IL-6 concentration >10 pg / ml, the odds for anemia were 5.3 times higher (95% confidence interval: 1.4–19.9, p = 0.009).Conclusion. The relationship between the activity of systemic inflammation and anemia in patients with SpA was confirmed. Taking into account the pathogenesis of AI, the aim of antianemic treatment is to achieve remission or minimal activity of SpA. Additional studies are required to determine the effect of anti-inflammatory therapy on the development and course of anemia in patients with SpA.

Objective: to assess the frequency and nature of prescribing antibiotics to patients with confirmed COVID-19 at the outpatient stage.Material and methods: a survey was conducted of 104 patients with confirmed COVID-19 and their medical records were analyzed. Patients received treatment in various outpatient facilities in the city of Saratov.Results: most of the patients sought medical help 6-7 days after the onset of the disease. Most patients (65-62.5%) had a mild course of COVID-19, and moderate and severe course was found in 28 (26.9%) and 11 (10.6%) patients, respectively. Before seeking medical help, 87 (83.6%) patients began to receive antibiotics on their own. After visiting the doctor, antibiotics were additionally prescribed to 6 more patients who had not previously taken them. Most often, aminopenicillins (17 patients), macrolides (49 patients), respiratory fluoroquinolones (27 patients) and cephalosporins (41 patients) were used. Combinations of two and sometimes three antibiotics were used in 46 (44%) patients. The most commonly prescribed antibiotics were azithromycin (44 patients), levofloxacin (27 patients), and parenteral antibiotic ceftriaxone (41 patients).Conclusion: in patients with an established diagnosis of COVID-19, a fairly frequent use of antibacterial drugs at the outpatient stage was revealed. The overwhelming majority of patients (83.6%) started using ABP on their own, before seeking medical help. Moreover, 44% of patients received combinations of two or three drugs. There are currently no convincing data on the feasibility of such a widespread use of ABP in outpatient practice in the vast majority of patients with diagnosed COVID-19.

The article presents data on the incidence of pain in patients with chronic kidney disease of various stages, the main causes of acute and chronic pain, the frequency of use of non-steroidal anti-inflammatory drugs (NSAIDs) by patients for pain relief. The article discusses the possible risks of an adverse effect of NSAIDs on kidney health. Unfortunately, often patients do not know about their CKD and take NSAIDs on their own, and doctors underestimate the condition of the kidneys when prescribing drugs to relieve pain.

The paper presents the results of simulation traction-dynamic tests of the promising universal tractor KhTZ-160U, obtained on the basis of PowerMix field test cycles. A technique for determining the efficiency of a tractor in an aggregate with an agricultural implement is given, which is based on the components of the power balance obtained by averaging the results of calculations for PowerMix field test cycles. Based on the results of calculating the indicators of reduced productivity, per hectare fuel consumption, the efficiency of a tractor in an aggregate with an agricultural implement and the likelihood of meeting agro-ecological requirements on the territory of Ukraine, the most promising options for equipping tractor KhTZ-160U with tires were determined. It is shown that the KhTZ-160U tractor has the best indicators of efficiency and environmental friendliness on dual tires 420/85R34 GoodYear 142 (A8), which can also carry out inter-row tillage. The base tire 480/70R34 Voltyre 143 (A8) has the worst performance and cannot be recommended for implementation, as it meets agri-environmental requirements in only 18% of Ukraine. The 540/65R34 Mitas 148 (A8) has the highest performance rating and is therefore recommended as a base.

The paper presents a mathematical model for determining the traction and dynamic performance of tractors using PowerMix field test cycles. The mathematical model was successfully tested, during which a set of traction-dynamic parameters of a wheeled tractor with the maximum discrepancy on individual indicators relative to experimental data, which is -8.4… + 7.9%. A plan of a simulation experiment is proposed, which takes into account the distribution of the annual volume of spring and summer-autumn tractor work by typical agricultural operations, and includes loading traction cycles with power take-off through PTO and hydraulic system of the tractor. To assess the efficiency of tractors based on a set of traction-dynamic indicators obtained from field PowerMix test cycles, developed a method of bringing the simulation results to the performance of the base tractor with a capacity of 100 kW, which corresponds to the basic cycles PowerMix. The technique makes it possible to compare tractors of arbitrary design solutions and power. As an example, the results of modeling the traction and dynamic performance of the New Holland T6.180 tractor on PowerMix field test cycles determined the average values of productivity and per hectare of fuel consumption plowed by the base tractor, which are 1,239 ha / h and 14.58 kg / ha, respectively

An analysis of the formation of the value of the kinematic lead/lag ratio of the tractor wheel drives is presented, taking into account the indicators of tractor agricultural tires. It is shown that the kinematic lead/lag ratio is formed as a result of the total influence of the internal gear ratio of the transmission and the values of the rolling circumference of the tires of the front and rear drive axles. It has been established that the actual values of the rolling circumference within tire groups, according to the rolling circumference index (RCI), have wide ranges of values. This can cause a wider range of kinematic lead/lag ratio variation of the front drive wheels, and in some cases even power circulation. For tires with a rolling circumference approaching the upper or lower limit of the interval within the rolling circumference index, as well as equipping the tractor with such tires, with an disadvantageous combination of the rolling circumference of the front and rear tires, the kinematic lead/lag ratio will go beyond the interval 1.01...1.05 which is recommended. It is shown that the kinematic lead/lag ratio can be either 0.982 or 1.074. Since even the use of the difference between the rolling indexes of the rear and front tires necessary for a particular tractor does not guarantee the recommended value of the lead of the front tires, it is imperative to determine it by calculation and check it experimentally in operation

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.

Very many areas of human activity are associated with greater or lesser risks. In order to make reasonable decisions, these risks must be properly assessed. The consequences of any risk can be characterized on the basis of two fundamental dimensions (metrics): (1) losses associated with the outcomes of implementation an unfavourable event; (2) probabilities that quantify the uncertainties in the occurrence of these outcomes. This article in a concise form presents and analyses approaches to subjective probabilities elicitation and combining the obtained individual estimates in group subjective probabilities estimation.

Property and other valuables insurance is widespread all over the world. An insurance company assumes the risk of damage or total destruction of the insured property. When this kind of damage or destruction is established, the company pays its client compensation (insurance premium) up to the amount specified in the insurance contract. For his part, the insured must pay a certain amount to the firm for the provision of insurance services. In any property insurance process, the question arises as to whether it is appropriate to insure the property for the price offered by the firm. The paper considers an approach to solving this problem based on expected utility theory.

Au/TiO2 catalytic coatings have been developed onto the inner surface of a quartz tube for photocatalytic applications. Gold nanoparticles with diameter 3–5 nm were synthesised using the citrate method, with sodium borohydride as a reducing agent. The nanoparticles were characterised by UV–vis spectroscopy, small angle X-ray scattering (SAXS), dynamic light scattering (DLS), and transmission electron microscopy (TEM). The photocatalytic activity of gold nanoparticles and Au/TiO2 catalytic coatings was studied in the reduction of 4-nitrophenol (4-NP) with green LEDs. The reaction rate follows Langmuir-Hinshelwood kinetics and increases with the light intensity until a plateau at 3 mW cm−2. The photocatalytic activity of gold nanoparticles was fully preserved in the Au/TiO2 coatings.

Introduction. The rail-to-earth transition resistance is an important parameter of electrified railways, which directly effects the electrical safety level of the traction network and the potential distribution in the upper structure track area. The increased potential adversely effects the operation of the power supply system, the safety of passengers and service staff. Moreover, the mentioned potential leads to the insulation damage of the signaling equipment and to the threat of the train traffic security. The high-speed traffic development in Russia involves the ballastless track usage. The transition resistance of the ballastless track differs from that of a ballast track.Materials and methods. The article considers mathematical model of the ballastless track for determining the rail-toearth transition resistance. The authors presented a description of the method for rail-to-earth transition resistance with a known input resistance of the rail track, determined experimentally.Results. The paper demonstrates relative values of the voltage drop on the the ballastless track structural elements. The obtained data will be used to analyse and calculate the modes of operation of the traction power supply system that occur in the rail track during short circuits in the traction network, and to assess the electromagnetic compatibility of electrical installations.Discussion and conclusion. Obtained results will lead to study the transition resistance of the ballastless track concerning high short-circuit currents drainage from the rails by simulating a short circuit both near the traction substation and away from it.

Introduction. The purpose of the research is to evaluate transition resistance modifications of the upper structure track in passing from the ballast to the ballastless track. These modifications effect the rail-to-earth potential difference. Moreover, they refer to the reverse traction system, to the reverse traction current of railway automation devices and to the required level of electrical safety guarantee.Materials and methods. The authors used both the analytical method of the rail-to-earth potential testing and the practical one based on experimental studies of the rail track transition resistance measurements. The authors carried out experiments on the Rozengartovka — Boitsovo — Bikin section of the Far Eastern Railway. This section includes the heavy freight traffic with the increased electric resistance of the track ballast by the upper structure redevelopment.Results. The research defines the main criteria of the rail-to-earth potential considering the 2×25 and 25 kV reverse traction of monophase AC systems with the 50 Hz frequency and depending on the experimental area location in terms of traction substations, on the climate and geological factors and on the freight traffic density.Discussion and conclusion. The obtained results will improve the accuracy of the rail-to-earth potential difference considering not only indicated factors, but also the upper structure type, track features and a feed line scheme for contact wire.

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.