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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.

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.

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.

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