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Russian Society of Cardiology (RSC)Developed with the special contribution of the Russian Functional Diagnostics Association, Russian Holter Monitoring and Non-invasive Electrophysiology Society, Russian Pediatric Cardiology Association.

Association of Cardiovascular Surgeons of Russia Russian Society of Cardiology (RSC)Association of Pediatric Cardiologists of RussiaRussian Scientific Society of Specialists in X-Ray Endovascular Diagnostics and TreatmentAll-Russian Public Organization for the Promotion of Radiation Diagnostics and Therapy "Russian Society of Radiologists and Radiologists".Task Force members declared no financial support/conflicts of interest. If conflicts of interest were reported, the member(s) of the working group was (were) excluded from the discussion of the sections related to the area of conflict of interest.

Progredient growth of morbidity and mortality of patients with community-acquired pneumonia (CAP) requires optimization of treatment including antibacterial therapy. Implementation of molecular-genetic methods of diagnostics of viral and viral-bacterial infections in clinical practice has significantly augmented the conception of etiology of community-acquired pneumonia. Seasonal fluctuation of CAP prevalence corresponds with growth of morbidity of acute respiratory infections and influenza which contribute to the etiological structure of CAP by increasing the risk of infection caused by staphylococci. The synergy between influenza A virus and S.aureus has been shown; it is associated with an increase of virus replication in the presence of specific staphylococcal proteases and the ability of viruses to increase adhesion of S.aureusin the respiratory tract, to decrease phagocytosis of S.aureus by macrophages/neutrophils and production of antimicrobial peptides, as well as to increase the probability of secondary bacterial co-infection. Therefore, the most important requirement for the empiric therapy agents of CAP is high streptococcal and staphylococcal activity. According to the current guidelines on antimicrobial therapy of severe CAP, antipneumococcic cephalosporins, macrolides, and fluoroquinolones are the basic treatment agents, but none of them have the combined high antistaphylococcal and antipneumococcal activity inherent in ceftaroline. The advantages of ceftaroline over ceftriaxone and levofloxacin in terms of the probability of reaching target concentrations for clinically relevant pharmacokinetic/pharmacodynamic parameters are shown. Meta-analysis of randomized clinical trials showed the higher clinical efficacy of ceftaroline in comparison to ceftriaxone with similar adverse event rate. Summarized analysis of antibiotic susceptibility data, pharmacokinetic/pharmacodynamic and clinical data, as well as negative epidemiological trends confirms the necessity of optimization of antimicrobial therapy of CAP for implementation of ceftaroline advantages against pneumococci and staphylococci in comparison to other β-lactams. Therefore, empiric treatment with ceftaroline is the most rational option for the therapy of CAP in critically ill patients during the season of respiratory viral infection.

Aim. The paper presents prevalence and disturbances of cardiac rhythm and conduction in children with a single ventricle (SV) at different stages of hemodynamic defect correction. It also analyzes risk factors of arrhythmia.Materials and methods. A total of 70 patients with SV was performed all stages of hemodynamic correction of defect. To assess disorders of rhythm and conduction, echocardiography, pulseoxymetry, cardiac catheterization, pulmonary angiography, ECG, and Holter monitoring were performed before and after surgery on all children at every stage of hemodynamic correction.Results. Absence of heart rhythm disturbances (HRD) at 1st stage of hemodynamic correction was 98.1%, at 2nd – 80%, at 3rd – 48.6% and at 4th – 41.5%. Sinus node dysfunction is the most often HRD from the second stage of hemodynamic correction. Statistical analysis showed significant decrease of saturation ((73 ± 12) и (81 ± 4)% correspondingly, p < 0.05) and increase of average pressure in the pulmonary artery after TCPC ((9.6 ± 4.2) and (11.5 ± 5.8)% correspondingly, p < 0.05) in children with heart rhythm disturbances in comparison to children without arrhythmias. The average age of children with arrhythmias after TCPC and after fenestration closure, correspondingly, was significantly higher than in the group of children without arrhythmias ((72 ± 43) mon and (52 ± 27) mon correspondingly, p < 0.05). Studies of arrhythmias in children with SV require follow-up as they significantly influence on the disease and life quality.

Aim. To study clinical and hemodynamic parallels in preschool children with arrhythmias in different age groups.Material and methods. Totally 195 children studied with idiopathic arrhythmias at the age of 0 to 7 y. o. — 82 with WPW syndrome, 55 with atrial tachiarrhythmias, 7 with AVNRT, 13 — with ventricular tachis (VT), 38 with ventricular and supraventricular onsets (isolated, group and their combination). Age groups: 1 — children 1 y. o. (n=72; 37%); 2 — 1-3 y. o. (n=37; 19%); 3 — 3-7 y. o. (n=87; 44%). All patients underwent standart laboratory assessment, electrocardiography in 12 standard leads, Holter monitoring, echocardiography.Results. In analysis of tachicardias course variants there was prevalence of of paroxysmal tachicardia in children of 3 to 7 y. o. (p=0,001) and permanent tachicardia in children less than 1 y. o. (p

The research is devoted to the evaluation of the depressor and constrictive components of the vascular reactiveness in the people with burdened heredity on atherosclerosis and the factors of risk of this disease’s development. The connection of the vascular reactiveness of peripheral arteries with the factors of risk of atherosclerosis development is discovered. The results of researches allow to suppose that atherogenic factions of lipoproteins, inflammatory cytokines produced by mononuclear of nitric oxide participate in the formation of pathological vascular reactions in people with atherosclerosis and with burdened atherosclerosis heredity on preclinical disease level.

The crystallizer is the most critical and most important functional unit of a continuous casting machine (hereinafter referred to as CCM). It is the main technological unit of the CCM, an assembly for removing heat during the solidification of the solidifying metal and the formation of the ingot. The main requirement for the crystallizer is to provide maximum heat removal from the solidifying steel to the cooling water, and to obtain a strong ingot shell with a good surface at the outlet of the crystallizer, which would not be destroyed by the heat of the liquid phase and the ferrostatic pressure. During the reconstruction of the CCM by the contractor company, drawings of crystallizers and crystallizer sleeves with a double‑cone internal geometry for casting 200 mm continuous cast billets were developed. The 200 mm continuous cast billet is a billet for the production of hot‑rolled seamless steel pipes. During the operation of the crystallizer sleeves with a double‑cone internal geometry, an accelerated wear of the protective coating in the lower part of the sleeve was noted, as well as an increased rejection of hot‑rolled pipes due to defects on the outer surface of the pipes. In order to identify the cause of the defect formation, complex metallographic studies of the outer surface of the pipes were carried out. As a result of the metallographic study, surface defects classified as steel mill scale on the outer surface of the pipes were identified. To minimize the “steel mill scale” defect and reduce the wear of the protective coating of the crystallizer sleeves, work was carried out to select the optimal conditions for the crystallization of the continuous cast billet: the use of crystallizer sleeves with a three‑cone internal geometry compared to a double‑cone was investigated; maintaining the temperature difference of the water at the inlet and outlet of the crystallizer within specified limits (ΔT) was tested. It was found that the use of a crystallizer sleeve with a three‑cone internal geometry for casting 200 mm billets and the stable behavior of the ΔT parameter made it possible to ensure the required quality of the surface of seamless pipes, reduce the wear of the protective coating of the crystallizer sleeves and increase the productivity of the CCM.

One of the main factors determining the final properties of metal products is the quantity, morphology and distribution of non‑metallic inclusions in steel. The article deals with the issues related to the use of calcium carbide in steelmaking production, instead of secondary aluminum and other deoxidizing materials, in order to improve the quality of the products. During the experimental work on the use of calcium carbide in steelmaking production, instead of secondary aluminum and other deoxidizing materials, second grade calcium carbide according to GOST 1460–81 was used. To determine the contamination of steel with non‑metallic inclusions, sampling was carried out from hot‑rolled products obtained from continuously cast billets. According to the results, it was found that the improvement of melt deoxidation in melts using calcium carbide can be achieved by increasing its consumption. In turn, the use of calcium carbide for deoxidation of the melt upon its release from the electric arc furnace into the ladle, instead of secondary aluminum ingots of grade AB87 according to GOST 295–98, helps to reduce the contamination of steel with non‑metallic inclusions.

Defects on the outer surface of seamless hot‑rolled steel pipes are formed both as a result of the defects’ transformation in the surface and macrostructure of the initial workpiece, and due to non‑compliance with the rolling technology. Timely detection of defects and elimination of the causes of their formation, allows you to get high‑quality products with high operational reliability. Detection of violations of technology, control of the technological process, carrying out metallographic studies allow classifying defects and establishing the nature and causes of their formation.The article presents the results of a metallographic study of a defect on the outer surface of a hot‑rolled seamless pipe. The genetic and morphological signs of the defect were determined. Descriptions of the appearance of the defect, the microstructure in the defect zone are given. A comparative analysis of the defect detected during magnetic powder control with defects on experimental pipe blanks with artificial defects was carried out. Based on the data obtained, the causes of the defect formation are determined, its classification is given.

The article describes the conducted research of the product “round flat‑link chain”, with the rupture of three links after heat treatment and mechanical tests at the consumer. The purpose of the research was to determine the cause of the destruction of the chain links. Visual inspection of the chain revealed breaks in three of the nine links. The rupture occurred in the area of factory branding. A metallographic study of two samples cut from a chain link with a break and a link without a break was carried out. During the study, a surface layer was found that was distinguishable from the main microstructure. The presence of the detected surface layer is due to surface hardening. The hardened area of the surface of the link with a break is almost two times smaller than in the link without a break. The amount of residual austenite is larger and larger in the link with the gap. As a result of the conducted studies, it was found that the destruction of the chain links occurred due to a violation of the heat treatment regime of the surface layer.

High quality of purchased resources plays a critical role under the conditions of severe international competition. Raw materials, materials and components are purchase for product production and their quality is an essential part in the production of steel at OJSC “BSW – Management Company of the Holding “BMC” holding». The problem of excessively high level of dynamic loads is especially acute for roughing stands. The main reasons for dynamic overloads are intense transient processes occurring in the rolling cycle, the presence of elastic constraints and gaps in the system, imperfection of electric drive system and errors made during development. Therefore, there is a need for selection of material and manufacturing technology for mill rolls capable to withstand such loads for a sufficiently long period. Investigations of destruction causes of experimental mill roll of stand roughing group of mill 150 of section rolling shop at OJSC “BSW – Management Company of the Holding “BMC” holding were carried out. Main classification features are established based on the analysis of the fracture. The results of metallographic studies of microstructure and chemical composition of central and subsurface zone roll fragments are presented. The reason of destruction of experimental mill roll was discovered – nonconformance of roll material grade with the requirements of technological instructions and normative documentation for rough group of stands No. 1–3

Establishing the true causes of defects is one of the main prerequisites for improving the quality of metal products. One of the undesirable phenomena in the production of continuously cast billets, hot‑rolled products is the oxidation of hot metal in the environment with the formation of scale on its surface. Defects, which are violations of the continuity of the metal and deviations from the normal specified macro‑and microstructure, signifi antly reduce the technological plasticity of the metal in the conditions of its processing and operational stability.After hot rolling of a circle of 95 mm steel grade 30MpV4, surface defects were found in the finishing line. To study and establish the nature of surface defects from hot‑rolled blanks, as well as continuously cast blanks, samples were taken.Analyzing metallographic studies of defects and the production technology of the studied steel grade 30MnB4, it was found that the defects were formed as a result of mechanical damage to the continuously cast billet in the area of the pulling‑correct unit. The reason for the formation of the defect is the ingress of scale on the guide rollers.

Seamless hot – rolled pipes are a popular metal product on the world market. During operation, pipelines are subjected to cyclic loads associated with temperature fluctuations, vibrations near compressor stations, and pressure drops in the transformed medium. One of the ways to ensure high performance properties is to manage the quality of pipe metal, including that laid in the process of metallurgical production. All the basic physical and mechanical properties of metal materials are structurally sensitive and significantly depend on both the grain size and the degree of uniformity of the grain structure, that is, on the different grain sizes. For metallographic research, samples of pipes with the size of 70,0×12,5 mm of S460NH steel were selected with satisfactory (#1) and unsatisfactory (#2) results of the impact. It was found that the inhomogeneous (multi – grained) microstructure in sample #2 was the reason for obtaining unsatisfactory results of the impact. As a result, it was found that one of the most important characteristics that can guarantee stable and satisfactory results of mechanical characteristics, in particular the impact performance, is a homogeneous grain structure.

One of the important tasks is to deliver to the consumer a calibrated high-quality metal in a saleable condition, which requires protection from atmospheric corrosion and adverse climatic factors, protection from contamination and mechanical damage for the period of transportation to the consumer by motor transport, and storage at intermediate warehouses before going into production. A comprehensive system approach is needed to preserve the quality and appearance of the products on the way from the manufacturer to the consumer. The use of modern packaging materials, such as paper with corrosion inhibitor and polypropylene fabric reinforcement, will allow to obtain permanent guaranteed protection of the rolled surface and expands the possibilities of transportation and sales markets of metal products. The testing stage of the corrosion inhibitor included the determination of its protective properties. It is established that the advantage of packaging of rolled products in anticorrosive paper is that it, combining the functions of packaging means and means of preservation, allows you to completely abandon the expensive and time-consuming preservation of metal products with oils and greases. The use of a volatile corrosion inhibitor in the composition of the paper provides full protection of rolled products.

Rolling rings as an important element of the rolling mill belong to the category of replaceable equipment, the quality of performance of which affects a number of operational characteristics, as well as the quality of rolled products. The material from which the rolling ring of the stand No. 7 is made must have the appropriate properties capable of perceiving high thermal loads for a long period of time without destruction, chipping and significant development of calibers. In this regard, there is a need to select the optimal option for the manufacture of rolling rings that can withstand such loads for a sufficiently long period of time. The study of the causes of destruction of the rolling ring 450×242×100 mm of high-speed steel, used at OJSC «BSW – Management Company of the Holding «BMC» in the cage number 7 mill 150 rolling shop. The results of metallographic studies of the microstructure and chemical composition of fragments of the destroyed rolling ring are presented. A detailed study and comparative analysis of the chemical composition and microstructure of samples of similar rings made of high-speed steel from two different suppliers, which showed high results in durability during operation, was carried out.

In a market economy, increasing the competitiveness of steel products is an urgent trend in science and practice. Development of production of new pipe steels in terms of pipe-rolling plant open joint-stock company «BSW – management company of holding «Belarusian metallurgical company» casted on continuous casting machine, was complicated by the emergence of low-alloy pipe steel grades of internal defects, which negatively affects the quality of the pipes. Visual evaluation of samples on the inner surface revealed rolled defects significant clusters, close to each other, having a longitudinal orientation. The edges of the defects are tortuous, torn. Defects found on the inner surface of the pipes are characterized as steel melting captivity and swelling. The reason for the formation of internal defects of hot rolled pipes «steel-melting captivity and swelling» was the rolling of defects in the macrostructure of the central zone (central porosity and axial liquation) of a continuously cast workpiece with a diameter of 200 mm.

Solution of actual problem of continuous improvement in productivity as a key indicator of staff efficiency of the industrial enterprise is achieved through integrated application of all elements of the organization of work in designing work process and adopting special measures to improve productivity. The efficiency of human resource management is due to the allocation of the key role of the employee and the application of modern methods of organization and behavior of production processes, with an emphasis on the rational organization ofworkplaces and the need for the management training.

Rolling is the final stage of the metallurgical cycle and has a great influence on the quantity and quality of products, as well as on various technological and economic indicators of the plant.The OJSC « BSW – Management Company of Holding «BMC» is working on the development and supply of hot-rolled round products for the automotive industry in Western Europe.The increasing requirements for the quality of the surface of hot-rolled steel are a powerful incentive to improve the technology of its production, which is impossible without the use of modern methods of control and proper identification of detected defects.The article presents the results of the study of defects of hot-rolled products of rolling mill № 1 850, having the rolling nature of formation.Metallographic study was conducted on the basis of: visual inspection of defects, in some cases with the preparation of a template for the study of macrostructure and location of defects; analysis of images of the microstructure of the cross section of the sample in the area of defects. With the help of characteristic external and microstructural features of defects, special etching in reagents, the causes of their formation were established, and recommendations for their minimization or complete elimination were proposed.

The problem of friction, wear of machine parts and cutting tools, the need to increase the life of machines makes the task of creating new high-performance, energy-saving technologies of hardening one of the main in engineering. In mechanical engineering, the problem of improving the physical, mechanical and operational properties in thin surface layers (~10 microns) of such parts as shafts, gears, measuring tools, drills, cylinders of internal combustion engines, etc. is important. Currently, these tasks are often solved by applying reinforcing coatings. Cementation is economical. The technology of cemented steels smelting, which is currently used by metallurgical plants, does not ensure stable production of fine-grained structure in products. At the same time, the capacity of machines and units are growing, and to obtain parts that can withstand higher loads while maintaining their overall dimensions, new steel grades are needed. The complexity of the configuration of gears with a thin tooth and a massive sleeve, and the need for minimal warping make heat treatment as difficult and responsible as a complex tool, such as shaped cutters. Therefore, for the manufacture of gears you want to assign steel with small hereditary grain size. In this article we will focus on the development and production of cemented steel in the conditions of OJSC «BSW – Management Company of Holding «BMC», in particular, the steel brand 16MnCrS5 commissioned by the European manufacturer of gearboxes and motors. To determine the grain size of the metal must be subjected to special types of processing for the manifestation of certain characteristics. These results allow us to draw conclusions about the need to adjust the chemical composition of steel grade 16MnCrS5 by introducing a system of modifying elements, which will reduce the tendency of steel to overheating, therefore, reduce the size of austenitic grains. On the basis of the revealed regularities on the influence of carbide-forming elements, a further system of steel modification is determined, which includes a complex of elements V, Nb, Ti.

In the process of the design of the machine, lath or unit the foundations of durability and reliability of individual components and parts are established. In the manufacture a great influence on the quality and performance of parts have technological factors. The reliability and durability of the most loaded mated parts, working parts of the machine depend largely on the correctness of the choice of the manufacturing method, the purpose of the appropriate hardening metal processing, the quality of the Assembly.Part shaft is present in any mechanism and plays an important role in ensuring of the functional performance of units and assemblies. During operation, the shafts are subjected to operating loads, resulting in defects. The diversity and complexity of modern structures, their operating conditions, methods of production and hardening of parts makes the technical diagnosis of the causes of destruction a very difficult task, which in some cases can be solved only with the help of a complex of modern physical methods of research, including fractography and microscopy.The article deals with the causes of destruction of the roll shaft of the working cassette of the wire block. On the basis of the fracture analysis, the main classification features are established: orientation, microgeometry, degree of plastic deformation at fracture and fracture energy, micromechanism of fracture. The fracture surface has a fine-grained fracture (formed under conditions of small plastic deformation) and is characterized by the presence of shiny flat areas on the fracture surfaceThe study of the microstructure after etching in a reagent «Nital» and reagent Oberhoffer. The chemical composition of a fragment of the shaft meets the stated grade of steel. The increased content of Nickel was revealed. Increased Nickel content is not associated with the destruction of the shaft, as Nickel has no negative impact on the properties of steel, and the finished product as a whole. Nickel has a positive effect on the properties of steel, increasing its strength without reducing ductility and toughness. The destruction of the roll shaft of the working cassette of the wire unit occurred as a result of multiple excess of the standard tightening torque when installing the shaft in the structure. «Overtightening» of the shaft led to cracking on the brittle mechanism of destruction

With the aim of obtaining scale with a high degree possibility of mechanical removal under the conditions of the section rolling shop No. 1, at the mill «150» JSC «Belarusian Metallurgical Works – Management Company of Holding «BMC» developed technological modes of production of wire rods made of low-carbon steel grades.The peculiarities of scale formation were studied, namely, the factors influencing the removability, obtaining the optimal thickness and its phase components on the wire rod diameter 5.5–6.5 mm in the cooling process immediately after rolling, intended for wire production.To obtain the necessary ratio of the phase constituents of the scales on the surface of the wire rod, the following factors was taken into account: the temperature of the layout of the turns on the roller table in the air cooling line; (uniformity along the length of the turn), the cooling conditions of the helix of the turns (prevention of the 4FeO = Fe3O4-Fe decay), where the condition of cooling the wire rod from 600 to 250 °С, not exceeding 100 s, must be observed.The results of metallographic studies of scale on the wire surface are presented. The introduced technological regimes provided the optimal thickness and the FeO / Fe3O4 ratio after the experimental rolling of the metal. Exhausted cooling regimes allowed to reduce the consumption of fiber for all types of wire.

In the pipe-rolling shop, on the site of preparation of mandrels and disc saws were the centerless turning and grinding complex VT-8 «Hetran» for repair of mandrels are used, studies have been conducted to test experienced grinding belts. The choice was based on a comparative analysis of the work of experienced grinding belts with usual industrial grinding belts. The resistance of grinding belts for one mandrel is calculated. A positive result (economic effect) was obtained by using experienced grinding belts.

Almost all metal at OJSC «Byelorussian Steel Works» – management company of holding «Belarusian Metallurgical Company» includes today a mandatory physical-mechanical tests which allow to estimate the parameters of the raw materials, to know the reasons for loss of strength and determine operational characteristics. In the Central Factory Laboratory (CFL), laboratory of physical and mechanical tests (LPMT) for the preparation of samples of reinforcement equipment is used of knives in the cutting machine SIMA GEL-30 for cutting rebar from the mill 320 rolling shop № 1 with a diameter from 6 to 24 mm. In the drop-hummer shop annually discards off for scrap waste up to 50 knives. Hydraulic shears of drop-hummer shop used knives set of production of OJSC «Kobrin tool plant «SITOMO», made of steel grade 30ХСНВФА, according to the TU14-1-4461. The staff of the Central laboratory LFMI proposed to use waste knives drop-hummer shop for the manufacture of knives for the chopping of the machine SIMA GEL-30. On the basis of the conducted researches the technological scheme was developed for production of knives for the chopping of the machine SIMA GEL-30 cold cutting of reinforcing bar mill 320 the rolling shop № 1.

Researches of the reasons of broken knives for the chopping of scrap metal of RS-1200 press scissors are conducted, the reasons of breakage are defined and it is established that premature failure of knives is connected with low values of hardness steel which have been a result of violations of technology of heat treatment at the producer’ plant.

Field tests of the witness samples of corrosion made of seamless hot-rolled pipes of various steel brands produced by JSC «BMZ – Management Company of Holding «BMK» were carried out in the operating pipelines at three oil fields. The results of the conducted researches made by the experts of RUP «ON «Belorusneft» permitted to define the most stable steel brands against corrosion for each of the oil fields: for a well 146 New and Davydovsky fields – brand steel TT309; for a well 270 Rechitsky fields – steel brands 20 and TT359; for a well 59 Ostashkovichsky fields – TT309 brand steel.

With the development of a new process for the production of seamless hot-rolled pipes, specialists of the enterprise encountered difficulties in determining the causes of unsatisfactory quality of pipes, determining their nature and causes. In this regard, this article contains created and developed «Classification of defects of hot rolled seamless pipes made of OJSC «BSW – management company of «BMC» holding».

Influence of temperature of metal fitting in the heating furnace on transformation of cracks is shown. It is established that the most preferable is «hot fitting» from the point of view of decrease of specific gas discharge for the blank heating and productivity increase.

The researches of influence of the cyclically modulated by amplitude high-frequency magnetic field on mechanical and tribotechnical characteristics of composites with polymericfluorine matrix are carried out for the first time.

It is shown that the important factor for receiving of high quality of continuously-casted ingot is construction and state of machine equipment of the slug continuous casting.

The transformation of the steel-smelting defect «netlike cracks» at all stages of processing from continuous casting to finished product was studied.

The effect of levetiracetam (a derivative of 4-phenylpyrrolidone) and its original analog, the compound GIZH-290, on primary generalized epileptic activity (EpA) in rat brain structures (sensorimotor cortex, dorsal hippocampus-CA3 field and lateral hypothalamus field) on EEG models of bemegridinduced seizures was studied. It was found that EpA, after the introduction of bemegrid, appears in 1–2 minutes in the form of prolonged generalized high-amplitude discharges and is registered within 3 hours. GIZH-290 (5 mg/kg, intraperitoneal, 15 minutes after bemegrid) causes a significant (p < 0.05) decrease in the number of epileptic discharges in the cortex and at the level of the trend in the hippocampus, which is accompanied by a decrease in the amplitude of the Epi-discharges. Levetiracetam at a dose of 200 mg / kg does not significantly change the severity of paroxysmal activity (the number of convulsive discharges and their duration) caused by bemegrid.

A convenient synthetic approach to meso-substituted with 2,2’-bipyridine and 1-(pyridin-2-yl)isoquinoline residues calix[4]arenes is reported. This approach involves the reaction of generated in situ 2-lithio-calix[4]arene with 1,2,4-triazine precursor with the following aromatization of the obtained adduct, and the aza-Diels-Alder reaction of the 1,2,4-triazinyl-substituted calix[4]arene with 2,5-norbornadien or in-situ generated 1,2-dehydrobenzene. The UV/fluorescence response of thus obtained meso-pyridyl-substituted calix[4]arenes to metal cations is studied.

Convenient methods for the synthesis of three monomers based on functionalized (bi)pyridines with using “1,2,4-triaizine” methodology have been developed.

Projects and experimental models of innovative concepts of VTOL aircraft with a hybrid propulsion system are attracting great interest and investment inflow all over the world. In this regard, when developing new concepts, it is important to understand how much better they will be than the currently operated rotorcraft and convertible aircraft in terms of reliability and flight safety, to be able to use them for passenger transportation in the future. In addition, when designing and choosing the optimal layout, it is necessary to know the contribution of each element and unit to the reliability of the aircraft as a whole in order to meet the requirements. To calculate the reliability indicators, the method of structural diagrams was chosen, and the calculation methodology was developed. The general classification of modern innovative concepts of convertible aircraft is considered, schematic diagram of hybrid propulsion system and its main parameters are determined. The article discusses the influence of the number of lifting rotor groups and their location on the possibility to continue the flight in hover mode in case of failure of one rotor group, the necessary power reserve of lifting electric motors is determined to ensure the given safety condition. In accordance with the adopted structural diagram, the main functional groups of the hybrid propulsion system of convertible aircraft operating in different flight modes are determined. The basic modes of a typical flight profile of a convertible aircraft are considered, time intervals characteristic for each mode are set. For each flight mode, a structural scheme of reliability of functional groups of a hybrid propulsion system is constructed, having a serial or parallel connection of elements, depending on their influence on the consequences of failure, the equation for calculating the probability of fail-free operation is derived. For lifting rotor groups, a combination of critical failures of more than one group is considered, and the equation is composed to calculate the probability of a catastrophic event in hover mode. Based on the obtained equations, the resulting calculation of the probability of fail-free operation, the probability of failure per flight hour for each flight mode was carried out separately and in total for the entire flight. Thus, for all flight modes, the probabilities of a catastrophic and emergency event, as well as a difficult situation in flight, are considered. A comprehensive analysis of the obtained results of reliability indicators calculation for convertible aircraft with six lifting rotors and two turboprop engines made it possible to conclude that it meets the requirements of the 25th part of aviation regulations for transport aircraft. A good potential margin of up to 10-2 was determined for the probability of a catastrophic failure in take-off, landing and transitional modes. The elements and subsystems that are critical for fail-free operation are identified, and ways to improve their reliability and the aircraft as a whole are proposed.

The article is devoted to the analysis of the consequences of the referendum on the UK’s membership in the European Union. The causes that contributed to the radical transformation of political processes and crisis phenomena in the framework of European integration processes are revealed. It is noted that the crisis of the British model of democracy and the rise of “monitoring democracy”, as well as the constitutional reforms in the UK, which were not brought to a logical conclusion, influenced the effectiveness of political institutions. The range of new complex issues of constitutional, legal, financial, economic, social and humanitarian nature that need to be addressed in the context of brexit is determined.The features of the development and implementation of the strategies of the United Kingdom and the European Union on the negotiation process are considered. The most important stages of negotiations on the problem of developing an agreement defining the conditions and principles of relations between the parties in the post-brexit period are studied. Particular attention is paid to the key controversial issues - the implementation of the financial obligations of the United Kingdom to the EU, guarantees the rights of EU citizens and their families living in the UK, as well as the preservation of the free movement of people, goods, services and capital between Northern Ireland and the Republic of Ireland.The author analyzes internal and external factors that have a direct impact on the course of the dialogue, arguments and counter-arguments of the parties, the reasons for the change in the positions of the United Kingdom and EU leaders on key issues of cooperation in the new historical conditions. There is a deep split between British society and the main political forces of the country on the issue of withdrawal from the EU. The factors that led the UK to a serious political crisis and the inability to develop an adequate and effective brexit strategy are considered.

Aim. To study the features of regulating the electrical activity and mechanical tension of smooth muscle cells (SMCs) of the guinea pig ureter as modulated by cyclic adenosine monophosphate (cAMP) in hypoxia. Materials and methods. The effects of isoprenaline (100 μM), forskolin (1 μM), 3-isobutyl-1-methylxanthine (IBMX, 100 μM) and tetraethylammonium chloride (TEA, 5 μM) on the contractile and electrical properties of isolated smooth muscle segments of the guinea pig ureter in normoxia and hypoxia were measured by the double sucrose bridge. Hypoxic conditions were created by placing the SMCs in Krebs solution containing (10.0 ± 0.2) vol. % O2. Results. It was found that an increase in the intracellular cAMP level caused by isoprenaline, the β-adrenergic receptor agonist, and activation of adenylate cyclase by forskolin, an inhibitor of phosphodiesterase IBMX, caused a decrease in the electrical and constrictor properties of the SMCs in the guinea pig ureter. The decrease in the level of oxygen in the perfusion solution resulted in the increase in the action potential amplitude and contraction of smooth muscles from the ureter. With an increase in the intracellular cAMP level, the activating effect of hypoxia on smooth muscle segments decreased. Inhibition of potassium conductivity of the ureteral SMCs with TEA in normoxia suppressed the cAMP-dependent processes induced by forskolin, whereas in hypoxia it caused the potentiation of an activating effect on the electrical activity and contractions of smooth muscle segments. Conclusion. Thus, the results suggest the involvement of cAMP-dependent signaling system in the influence of hypoxia on the electrical and contractile properties of ureteral SMCs. Modification of the intracellular cAMP level reduced the stimulatory effect of hypoxia on the smooth muscle strips of the ureter caused by increase in the ionic conductivity of the membrane and contributed to their adaptation to environmental conditions.

98 patients from 2 to 12 years old were observed with infectious mononucleosis (IM). Diagnosis was confirmed by the detection of M- and G-antibodies to EBV, CMV, HHV6, PCR DNA these viruses, bacteriological and blood-tests investigations. 58 patients in the complex therapy was given probiotic bifidumbacterin forte 45—90 doses a day (1-st group). The comparison group consisted of 40 patients with IM receiving symptomatic complex therapy and antibiotics (2-nd group). The observations shoved significant decreasing of length of clinical symptoms IM in the 1-st group with comparison of the 2-nd group. The investigation of concentration DNA these viruses (1-st group) demonstrated its rapid decreasing in blood to the second week of mononucleosis. The obtained results allow to recommend bifidumbacterin forte in the complex therapy in children with these infections.

Pyrene-based compounds have a great potential as fluorescent chemosensors for various analytes including common nitro-explosives, such as 2,4,6-trinitrotoluene (TNT). Compounds having two pyrene units in one molecule, such as bispyrenylalkanes, are able to form stable, bright emissive in a visual wavelength region excimers both in non-polar and polar environments. In this work we wish to report that in non-polar solvents the excimer has poor chemosensing properties while in aqueous solutions it provides significant “turn-off” fluorescence response to TNT in the sub-nanomolar concentrations.

Two ethyleneglycol esters of 1-pyrene carboxylic acid were studied as chemosensors for the fluorescence “turn-off” detection of two nitro-containing analytes, such as antiviral drug Riamilovir (Triazavirin ®) and herbicidal agent dinitro-ortho-cresol (DNOC). In both cases the dramatic fluorescence quenching was observed with quenching constants as high as 3·104 M-1 and limits of detection (LOD) as low as 100 ppb.

Aim. To study the ionic mechanisms which underlie regulation contractile activity of vascular smooth muscles and the erythrocytes membrane potential from spontaneously hypertensive rats.Materials and methods. The effect of acetylcholine (ACX), 10 μM, and Ca2+ -ionophore A23187, 10 μM, on the contractile reactions of isolated smooth muscle segments of the aorta from 11-week-old spontaneously hypertensive rats (SHR) and Wistar – Kyoto rats (WKY) induced by phenylephrine (PE), 1 μM, was measured by the mechanography. 11-week-old SHR were divided into control and experimental groups depending on the drug administration (amlodipine 10 mg/kg given intragastrically). Blood pressure (BP) in SHR was measured before and after treatment. The amplitude of the hyperpolarizating response (HO) and the activity of Ca2+-dependent K+-channels of the erythrocyte membrane of SHR were performed with potentiometric method.Results. In response to the stimulating effect of the ACX or the calcium ionophore A23187, the smooth muscle segments of the aorta from the WKY and SHR precontracted with PE were relaxed. To the addition of the ACX, the vascular segments of the SHR responded with a stronger dilatation than the WKY segments, but not the action of the Ca2+-ionophore. Treatment of SHR with blocker of Ca2+-channels of L-type amlodipine caused a decrease the BP, and an increase in the relaxing effect of intact aortic segments on the ACX and Ca2+-ionophore. There was an increase the amplitude of HO and activity of Ca2+-dependent K+-channels of the erythrocyte membrane from SHR.Conclusion. Relaxation of vascular smooth muscle in SHR is caused by changes in the endothelial function and Ca2+-dependent ionic conductivity of the myocyte membrane. An increase of the hyperpolarizating response of the erythrocyte membrane from rats with spontaneous hypertension is associated with activation of potassium channels. The selective effect on these intracellular targets can serve as a basis for the development of antihypertensive drugs.

The task solution of optimizing the parameters for an unmanned high-altitude airship and its power system in order to obtain the maximum of air standing patrol duration over a given geographic point requires an effective comparative analysis of the applicability of solar insolation as the main energy source for a power plant under various altitude, latitudinal, seasonal and wind conditions. The availability of a large number of input parameters for designing such a vehicle leads to the conclusion that it is necessary to use the universal specific energy characteristics of a high-altitude airship and its power plant to simplify the analysis and evaluation of technical solutions effectiveness. The main factor determining the power consumption of the power plant is wind flow speed in a given air standing patrol area. It is also known that solar energy is the most affordable source for long-term energy supply. In most cases, the analysis of solutions is reduced to assessing the ratio between the impact of two natural phenomena, solar energy and wind energy, on the high-altitude airship, for this purpose a simplified model of an airship was designed, which can also be applied to a solar energy airplane. In this work, the value of the available and required power per unit of the aircraft mass is selected as the main performance criteria. The available power is determined for any geographical point with the parameters of latitude, altitude and season (day of the year). The required power is determined by the flight altitude, speed and wind direction. Comparing the values of specific characteristics in space-time coordinates, it is possible to perform an effective analysis of the excess or shortage of available solar energy at a given geographical air standing patrol zone, for different altitudes and days of the year. Using the parameters related to aircraft take-off mass, we are also able to define the required dimensionality of the aircraft to carry out continuous aircraft air standing patrol at a given space point.

Introduction. The article represents the mathematical model of commercial vehicle’s hydraulic retarder. The model is based on the mathematical model of the variable filling hydraulic dynamometer.Materials and methods. The retarder model was designed with the possibility of its integration with the mathematical model of the engine cooling system. For this purpose, the state function of fluid temperature in a working chamber of the retarder was added to the retarder model. Consequently, fluid compression in the working chamber was included into the model to avoid unlimited filling because of possible high pressure at the retarder inlet.Results. The simulation model of the retarder was established as LMS Amesim submodel using C-programming language. For testing, the retarder simulation model was integrated with the Amesim models of the engine cooling system and with the powertrain and vehicle movement dynamics. In addition, brake torque regulation wassynthesized on PI controllers.Discussion and conclusions. During simulation of the vehicle movement on the mountain route expectable results were obtain, such as continuous braking via the retarder, which led to increasing of the cooling system’s fluid temperature. Therefore, overfilling of the retarder working chamber didn’t occur through the fluid compression. The retarder model could be applied to determine retarder design influence at vehicle functioning. For instance, it could be used for development of the algorithms’ control.

The effects of a new racetam derivative with anticonvulsant activity GIZh-290 (2-oxo-4-phenylpyrrolidin-1-yl) acetic acid and levetiracetam for the content of neuroactive amino acids aspartate, glutamate, taurine, glycine and GABA in homogenates of the hippocampus and prefrontal cortex (PFC) of rat brain using the HPLC method with fluorescent detection were studied. In the hippocampi of intact rats HIZh-290 (5 mg/kg, ip) increased the levels of glutamate, glycine and GABA by 22, 42 and 28 %, and levetiracetam (600 mg/kg), on the contrary, reduced them by 18, 26 and 26 %. At the maximum of lithium-pilocarpine seizures, a decrease in the content of aspartate (-19 %) and an increase in glycine in the PFC (+24 %) were detected. Preliminary administration of GIZh-290 and levetiracetam did not affect these parameters, but caused an increase in taurine concentrations in the PFC homogenates. Thus, the indicators studied are not markers of anticonvulsant action of levetiracetam and GIZH-290, but indicate differences in the mechanisms of the drugs anticonvulsant effect formation.

A convenient method for the obtaining of 3,6-diaryl-1,2,4-triazines substituted with residues of higher alcohols in the position of C5 via the ipso-substitution of cyano group in under the solvent free conditions was reported. This method indicates a new example for the functionalization of the 1,2,4-triazines via the substitution of the cyano group.

The study was aimed to compare the psychopharmacological effects of 2 anticonvulsant drugs levetiracetam ((S)-2-(2-oxopyrrolidin-1-yl) butanamide) and the new compound, GIZh-290 (2-oxo-4-phenylpyrrolidine-1-yl) acetic acid) on behavioral spectra of inbred mice BALB/c and C57BL/6 under conditions of "closed cross-maze" test. It was found that after 5-fold i.p. injections levetiracetam (600 mg/kg/day) reduced the cognitive and motor ability of C57BL/6 mice, while in BALB/c mice the drug increased anxiety and diminished motor activity. In contrast, the substance GIZh-290 (5 mg/kg/day, i.p.) had no effect in C57BL/6. Compound GIZh-290 (5 mg/kg/day, 5 days, ip) does not affect the behavior of C57BL/6 mice, but depressed the motor activity in BALB/c mice.

Aim. The effect of hypoxia on the electrical and contractile activities of smooth muscles cells (SMCs) of the guinea pig ureter was studied by the method of the double sucrose bridge.Materials and methods. This method allows registering simultaneously parameters of the action potential (AP) and the contraction of SMCs, caused by an electrical stimulus.Results. It was found that lowering the oxygen content in the perfusion solution for 10 min resulted to an increase of electrical and contractile activity of ureteral SMCs. Addition of tetraethylammonium chloride (TEA, 5 mM) – nonselective blocker of potassium membrane conductance – in hypoxic conditions causing an additional increase in the amplitude of the AP, duration of the AP plateau and the contractile responses of smooth muscles. Thus, the hypoxia decreased the potassium membrane conductance of ureteral SMCs. Inhibition of the effect of the α1 -adrenergic receptors agonist phenylephrine (PE, 10 mM) on the electrical and contractile properties of SMCs in hypoxic condition indicate the involvement of the protein kinase C-dependent signaling system in effects of hypoxia. Pretreatment of ureteral smooth muscles with bumetanide (100 mM) – selective inhibitor of Na+,K+,2Cl- - cotransporter (NKCC) – caused a decrease of the activating effect of hypoxia on the SMCs of guinea pig ureter.Conclusion.Thus, the impact of hypoxia on the regulation of electrical activity and contractions of smooth muscles of guinea pig ureter may be due to changes in ion permeability of membranes SMCs and operation of ion-transporting systems.

The purpose of the research was to study the influence of hydrogen sulfide donor NaHS on red blood cells membrane potential changes caused by the activation of Ca2+ dependent K+ channels in the presence of calcium ionophore or artificial electron donor system ascorbate phenazine methosulfate.Materials and methods. We used the packed erythrocytes obtained from venous blood of 25 healthy volunteers at the age of 20-27 years. Registration of the membrane potential of erythrocytes in the presence of Ca2+ ionophore (A23187) or artificial electron donor system ascorbate – FMS was performed with potentiometric method based on the fact that in the presence of the protonophore distribution of H + depends on the membrane potential Em like as Em = RT/F (pHi – pH0 ). Here pHi and pH0 are pH of the incubation medium and cytoplasm, respectively. An amplitude of hyperpolarizing response (HR) was calculated as an integral characteristic of Ca2+-dependent permeability for K+.Results. The addition of NaHS at concentrations from 0.2 mM to 0.005 mM into the cells incubation medium caused a change in the amplitude of hyperpolarizing response of erythrocyte membranes induced by both methods. In the presence of 0.005 mM NaHS the amplitude of A23187-dependent HR increased significantly, whereas the amplitude of the redox-dependent HR decreased. Suppression of A23187-dependent HR in the presence of higher concentrations of NaHS was more pronounced than the suppression of the amplitude of redox-dependent response. The amplitude of A23187-dependent HR increased under the joint action of hydrogen sulfide and the blocker of Na+, K+, 2Cl- -cotransport (NKCC) bumetanide, and the amplitude of redox-dependent HR decreased in comparison with the parameters obtained in the absence of a blocker.Conclusion. It is found that hydrogen sulfide exerts a modulatory effect on K (Ca2+) - channels of erythrocyte membrane. The effect of H2 S depends on the method of activation of the studied channels. A23187-dependent HR was more sensitive to H2S in comparison to redox-induced HR of erythrocyte membrane. The effect of NaHS on the amplitude of the HR in the presence of NKCC blocker bumetanide also depended on the method of stimulation of channels.

The aim of this study was to investigate the role of the Na+, K+, 2Cl– -transport and potassium conductance, in the implementation of the effects of carbon monoxide in the SMC taenia coli and ureter of guinea pig.Materials and methods. The study was conducted by the method of double saccharose bridge. Was studied the effects of carbon monoxide donor CORM2 in ureter and smooth muscle of guinea pig of taenia coli, in normal Krebs solution, against inhibitor-bumetanide and potassium channel blocker tetraethylammonium chloride (TEA). Studied the effects of bumetanide in normal Krebs solution and the background of TEA.Main results. CORM2 causes inhibition of contractile activity of SMC taenia coli and guinea pig ureter. Its effect is weakened by bumetanide and TEA. Bumetanide causes inhibition of contractile activity of SMC taenia coli, and its effect is weakened by TEA.Conclusions. In this way, it shows that there are tissue-specific mechanisms of interrelation effects CO and ion conductivity.

XRD investigation of Ti-2B system was carried out with the purpose of determining of structural changes in this system during mechanical activation. The size of coherentscattering region (CSR size) and kind II stresses (microstresses) were calculated by diffraction peaks profile analysis. It was determined that initiation of the synthesis reaction directly in mill is taking place at achievement the value of microstresses for titanium approximately equal to its yield point. Spontaneous reaction in a mill indicates that mechanical activation gives essential structural changes in Ti-2B system. So mechanical activation has essential influence on structural condition of Ti-2B system. Titanium diboride synthesized by high-temperature combustion and by mechanosynthesis have approximately equal crystallites size. These results could clarify the processes of materials structural condition after mechanical activation and have a matter for materials science.

The purpose of this research was to study electric and physiological mechanisms of the achievement of the antoconvulsant effect of the new original beprodon combination together with determination of determinant brain structures – therapeutic targets.Materials and Methods. Partial (focal) and secondary generalized convulsions were generated using the method of creation of a chronic epileptogenic focus, caused by the cobalt application on rats’ brain.Results: it was revealed, that at the first stage of the epileptic system (ES) beprodone is targeted to cortical focuses, and at the second stage – to subcortical focuses, generating epileptic activities. Conclusion: the beprodone effect depends on the stage of the epileptic system development and is targeted to determinant focuses.