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The article examines the experimental and theoretical justification of the use of basalt fiber, as a promising material, with the help of which it is possible to obtain a new class of building materials. As a result, it was established that an increase in temperature contributes to an increase in alkali resistance of the fiber. The mass loss during aging in an alkaline solution after 28 days is about 5%, while the initial fiber loses more than 30% of the fiber mass during this time. A further increase in the temperature of isothermal aging is not effective due to a decrease in alkali resistance of the fibers and economic impracticability. To explain the processes occurring in the structure of the fiber during its heat treatment, X-ray images and spectra of the original and heat-treated fiber were obtained. In the process of heat treatment from 300 to 500 0С, the processes of defect healing, changes in the chemical composition and surface structure of the fibers occur as a result of Fe+2 → Fe+3 oxidation and the formation of iron oxide tetrahedra [FeO4]Na with the attraction of alkaline cations to the surface of the fibers. The expediency of thermal treatment of basalt fiber at a temperature of 500 0C is substantiated, which leads to compaction of the fiber structure and contributes to increasing its alkali resistance, which is confirmed by the morphostructural features of the surface of heat-treated basalt fiber aged in cement mortar.

There are three groups of patients with abnormalities of magnesium homoeostasis. The first one include patients with magnesium deficiency (low total body magnesium content) and a resultant hypomagnesaemia (low serum magnesium concentration). Patients with hypomagnesaemia (serum magnesium concentration

The purpose of the study is to organize physical therapy classes and develop a program that includes an adapted method of health-improving walking for rehabilitation in the post-covid period. This means of physical culture can provide the maximum level of functional and physical characteristics to achieve high performance, emotional mood, and healthy life activity. The study involved bachelors in the Siberian State Scientific and Technical University named after M. F. Reshetnev, who had been ill with COVID-19. Classes of therapeutic physical culture will allow to reveal the great adaptive potential of the human body, to form a long-term adaptation, which consists in the restructuring of the body at the molecular, cellular level, in tissues, organs, organ systems and intersystem level, which determines the positive morphological and functional features of the trained organism as a manifestation of the biological norm. The frequency, intensity, direction of physical exercises, their duration and combination, the level of fitness, individual characteristics of those engaged and a number of other factors determine the nature and degree of these changes in the body. In future studies, we plan to use health-improving walking for rehabilitation in the period after AIDS for university teachers aged 50-59 years, as the most vulnerable during the COVID-19 pandemic. In conclusion, it should be noted that when exposed to physical exertion, muscle fibers are regenerated, becoming overgrown with a larger amount of protein material than it was originally. That is why the physical capabilities of the muscles are improved, due to the distribution of the load on a larger amount of muscle tissue. The synthesis of more muscle fiber requires the delivery of more oxygen and nutrients to the cells not only of the muscles, but also of all body systems. Increased blood flow contributes to an increase in the lumen of blood vessels, which increases the efficiency of the cardiovascular system, which is especially important during rehabilitation in the post-covid period. © 2021 by authors, all rights reserved. Authors agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License

The article proposes organizational and methodical provision of financial and economic security management of the enterprise and develops a methodical approach to assessing the level of FES management. The views of various authors on the definitions «economic security» and «financial security» are summarized, and the author’s vision of «financial and economic security» is provided, which should be understand as a complex system with a specific set of characteristics, aimed at ensuring the effective use of all types of resources: material, financial, labor, etc., and the prevention of internal and external threats. The basic principles of financial and economic security management of economic entities are outlined. The description of two blocks of organizational and methodical provision of the enterprise’s FES is provided: organizational block and methodical block. Existing methodical approaches to assessing the level of financial and economic security of business entities are considered. It is concluded that the most appropriate is to use the methodical approach proposed by the authors, which is aimed to improve the differential approach to assessing the level of management of financial and economic security of enterprises. The essence of the method is to improve the detection of the significance degree of partial integral indicators. As a result of the conducted research, the general scheme of organizational and methodical support of financial and economic security management of the enterprise was proposed. That scheme, based on the various factors analysis that determine the state of the enterprise and tendencies of its development, demonstrates the necessary set of measures for raising the level of the enterprise’s FES. It is concluded that the proposed methodical approach to assessing the level of the enterprise’s FES management enables to get rid of subjective factors and to determine the aggregate value of all indicators of functional criteria of financial and economic security of economic entities.

Topicality. Diabetes mellitus is an important social and medical problem, as it causes the development of dangerous complications that lead to disability and mortality. This disease is characterized by a multi-vector pathogenesis that requires a comprehensive approach to treatment. Due to the use of mixtures of medicinal plants in the treatment of diabetes, it is possible to cover all aspects of the development of this disease and its complications. In addition, the niche of the pharmaceutical market of Ukraine with phytomixtures is almost empty.Aim. To study the hypoglycemic activity of the herbal mixtures, which are used in folk medicine for diabetes mellitus type 2 prevention and treatment, but do not have a scientific basis and to establish their conditional therapeutic dose.Materials and methods. The study has been performed in male albino rats weighing 180-200 g, during 20 days they have been receiving orally for preventive treatment aqueous extracts (1:10) of the studied herbal mixtures at a dose 6 mL/kg/day, 9 mL/kg/day and 12 mL/kg/day and comparison drugs – the official herbal mixtures “Arfazetin” at a dose 9 mL/kg/day and tablets metformin at a dose 60 mg/kg/day. The study of hypoglycemic properties and the establishment of a conditional therapeutic dose of the studied mixtures was carried out using glucose loading tests. All experiments have been performed in accordance with general ethical principles with the recommendations of the EEC Council directive 2010/63/EU about the protection of animals used for scientific experiment.Results and discussion. The results of the study showed the 20-day preventive treatment by the herbal mixtures reduced alimentary hyperglycemia at the 30th minutes of OGTT and helped regulate carbohydrate tolerance disorders by reducing hyperglycemia at the 15th minutes of IPGTT. The highest hypoglycemic activity showed the herbal mixture No. 7 in a dose 12 mL/kg/day, which was almost on a par with the comparison drug – tablets metformin, but exceeded the official herbal mixture “Arfazetin”. In addition, the dose-dependence of the effectiveness of all five studied herbal mixtures was established.Conclusions. For the first time, it was conducted the screening study of hypoglycemic activity of the herbal mixtures, which are used in folk medicine for the prevention and treatment of diabetes mellitus type 2. It was determined that the greatest effectiveness in terms of the ability to reduce alimentary hyperglycemia during OGTT and reduce impaired carbohydrate tolerance during IPGTT show the herbal mixture No. 7, which includes Inulae rhizomata et radices, Helichrysi arenarii flores, Maydis style cum sigmatis, Origani herba, Rosae fructus, Taraxaci radices. It was established its conditional therapeutic dose 12 mL/kg/day.

A number of previously undescribed derivatives of 2-amino-5-(2-aryl-2-oxoethyl)thiazol-4(5H)-one containing electron-donating substituents in the aromatic ring were synthesized by the reaction of (E)-4-aryl-4-oxobut-2-enoic acids with thiourea. Reduction of the reaction products with NaBH4 yielded diastereomeric alcohols, whereas bromination in AcOH was accompanied by elimination of HBr and the formation of (Z)-2-amino-5-(2-aryl-2-oxoethylidene)thiazol-4(5H)-ones.

Arylideneketones are commonly considered as convenient starting materials for obtaining compounds of potential pharmaceutical interest. Heterocyclic α,β-unsaturated representatives of this series possess chemical and biological properties worth study in details. Particularly, substituted thiazole cycle, incorporated into such a system, allows obtaining of new biologically active products suitable to their consequent chemical modification. In this communication we focus attention on 2,4-disubstituted 4-(1,3-thiazol-5-yl)but-3-en-2-ones on the background of 2,4-dihalogen-5-formylthiazole, several relevant methods of their synthesis and prospective directions of further chemical modification.

The equilibrium between different tautomers that can be colored or colorless is an important feature for rhodamine dyes. Presently, this phenomenon is mostly discussed for rhodamine B. Herein, we studied the tautomerism and acid–base dissociation (HR+ ⇄ R + H+) of a set of rhodamines in organic media. Form R is an equilibrium mixture of the colored zwitterion R± and colorless lactone R0. Absorption spectra in 90 mass% aqueous acetone reflects the correlation between the dyes structure and the equilibrium constant, KT = [R0]/[R±]. Increase in the pKa value on transferring from water to organic solvents confirms the highly polar character of the R± tautomer. To reveal the role of the solvent nature, the tautomerism of an asymmetrical rhodamine, 2-(12-(diethyliminio)-2,3,5,6,7,12-hexahydro-1H-chromeno[2,3-f]pyrido[3,2,1-ij]quinolin-9-yl)benzoate, was examined in 14 media. This chain–ring tautomerism is an intramolecular acid–base reaction; the central carbon atom acts as a Lewis acid. The interaction with other Lewis acids, Li+, Ca2+, Mg2+, and La3+, results in rupture of lactone cycle. In polar solvents, lactones undergo photocleavage resulting in formation of highly fluorescent R±, whereas the blue fluorescence and abnormally high Stokes shift in low-polar media may be explained either by another photoreaction or by spiroconjugation and charge transfer in the exited state.

Transient ischemic attack (TIA) in the vertebral-basilar system (VBS) is characterized by an acute onset of focal neurological symptoms due to short-term local ischemia of the brain. According to various authors, temporary neurological manifestations of circulatory insufficiency in VBS can progress to complete stroke within 2-5 years in 30-50% of patients, leading to disability of about 80% of patients. Its diagnosis is associated with some difficulties due to the variability of clinical manifestations, clinical similarity with other diseases and, as a consequence, incorrect therapeutic tactics. The aim of the study was to investigate changes of endothelial function in TIA in VBS by determining the levels of homocysteine (HC) and vascular endothelial growth factor (WEGF) at different stages of neurological deficiency (ND). 78 patients with TIA in VBS were examined. The questionnaire developed by us was used to determine the stage of ND in TIA. The level of HC was determined by enzyme-linked immunosorbent assay. WEGF was determined using the "sandwich" method of enzyme-linked immunosorbent assay. In the group of patients with stage I ND, a tendency to HC increase in 1.1 times was detected compared with almost healthy persons (AHP), stage II - HC increased in 1.5 times (p

Лихоманка є найпоширенішою скаргою під час огляду педіатричних пацієнтів, найчастіше обумовлена вірусними або бактерійними інфекціями. Проте в деяких клінічних ситуаціях визначення причини лихоманки суттєво утруднене та може потребувати широкого кола диференційної діагностики, яка включає численні лабораторні тести і різноманітні специфічні методи візуалізації різних структур організму дитини. У рідкісних випадках персистуюча лихоманка тривало залишається лихоманкою невідомого походження. Під лихоманкою неуточненого ґенезу розуміють патологічний стан, основним проявом якого є підвищення температури тіла понад 38,3°С із багаторазовими підйомами протягом 3 тижнів і більше, етіологія якого не встановлена, незважаючи на проведений комплекс діагностичних досліджень. Гарячка неуточненого ґенезу є однією з найскладніших клінічних ситуацій для медичних працівників, оскільки не існує жодного діагностичного «золотого» стандарту і дотепер залишається викликом для кожного лікаря і потребує ретельного підходу до кожного конкретного випадку. Основним напрямом діагностичного пошуку в дитини з тривалим підвищенням температури тіла є виключення трьох груп захворювань: автоімунних, онкологічних та інфекційних. Наведено клінічний випадок із дебютом захворювання з лихоманки неуточненого ґенезу в дитини. Особливість цього випадку полягає у відсутності протягом тривалого часу достатньої кількості клінічних діагностичних критеріїв запальних захворювань кишечника. Розглянуто послідовний процес диференційної діагностики. Дослідження виконані відповідно до принципів Гельсінської Декларації. Протокол дослідження ухвалений Локальним етичним комітетом (ЛЕК) всіх зазначених у роботі установ. На проведення досліджень отримано поінформовану згоду батьків дитини. Автори заявляють про відсутність конфлікту інтересів.

60 patients after a hemispheric ischemic stroke (IS) were examined. Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Frontal Assessment Battery (FAB), Trail Making Test A and B (TMT), and the Clock Drawing Test (CDT) were used for the cognitive status assessment. A decrease in the MMSE, FAB and MoCA score compared to the control group (CG) (p

About 25% of ischemic strokes remain without an established cause. The article describes the characterization of some hereditary and acquired thrombophilias, which play a significant role in genesis of stroke. One of the ways to solve the problem of etiological diagnosis of thrombotic states is to identify the markers of hereditary or acquired pathology and to conduct molecular genetic typing of the hemostasis system factors. Thrombophilia screening is required for all patients with ischemic strokes of unknown etiology.

The data of 61 medical cards of patients with multiple sclerosis has been analyzed. 47,54% of patients reported pain as a symptom of multiple sclerosis, following types of pain were observed: neuropathic pain (оngoing extremity pain, Lhermitte's phenomenon), nociceptive pain (headache, back pain) and mixed pain (painful tonic spasms, spasticity pain). Only 17,24% of patients received therapy to treat pain.

The reaction of bromo-substituted chalcones with various diamino-compounds leads to the fused heterocyclic products, aziridinylpiperazines, exhibiting photoreactivity in the crystalline state. Crystals of 4-nitrosubstituted compounds of this family change their color from yellowish to deep violet-blue, 4-cyanosubstituted ones – from yellowish to pink at UV irradiation. Discussion on the mechanism of this phototransformation is still in progress, however, several facts points to the free radial nature of the photogenerated colored semi-products stabilized only by crystalline state of the irradiated samples. Formation of a mixture of positional isomers at interaction of bromo-chalcones with asymmetric diamines of aliphatic/alicyclic or aromatic series at synthesis of the title compounds is of significant interest as well.

The aim of the article is to analyze the adequacy of a set of indicators characterizing the state of Ukraine’s industrial security, and to diagnose it on the basis of indicators supplemented by the authors. The set of indicators envisaged by the current regulatory framework for assessing the level of industrial security of Ukraine is analyzed, positive and negative aspects of their application are identified. The key indicators of industrial security of Ukraine describing production performance, degree of depreciation of fixed assets, profitability of operating activities and efficiency of enterprises by key economic activities are analyzed. Based on the analysis, threats to economic security and government measures aimed at enhancing industrial security are identified. The necessity of structural changes in the economy is argued. The authors have come to the conclusion that the analysis of the industrial security of Ukraine reveals the key strong and weak positions of the country in this area. Management at the national level, aimed at eliminating the identified threats to industrial security, will make it possible to comprehensively solve the pressing economic problems. The restructuring of the industry will make it possible to strengthen the export potential of Ukraine, ensure an adequate level of profitability of enterprises and resolve a whole range of related social issues.

Статтю присвячено розгляду сучасних тенденцій застосування цифрових технологій для налагодження процесів управління міжнародною міграцією. Визначено найактуальніші цифрові можливості у сфері міжнародної міграції, особливості застосування окремих цифрових технологій у процесах міжнародної міграції, приклади їх можливого практичного застосування. Розглянуто можливі виклики організації процесів міграції, пов’язані із розвитком цифрових технологій.

Various diaryl/hetaryl representatives of penta-1,4-dien-3-one series attract the attention of synthetic chemists during several decades owing to the possibility of their consequent chemical modification resulted in obtaining compounds of potential interest to materials science. In addition to their synthetic importance, title diarylideneacetones can be applied directly as medical drugs, such as antioxidants and anti-inflammatory agents. In this communication, we report the synthesis of a series of new asymmetric thiazole cycle containing diarylideneacetones, which further demonstrated high regioselectivity in their reaction with hydrazine. To clarify this feature, quantum-chemical modeling of the cyclization process was conducted.

In the last decades, epidemiology and strategy of managing patients with meningitis have changed significantly, however the problem of their early diagnosis and differentiation remains relevant. Bacterial meningitis is life‑threatening condition, which determines the expediency of prompt etiotropic treatment. Conversely, many types of aseptic meningitis do not require differential treatment, however, before the liquor examination, it is impossible to reliably establish the type of meningitis. The main task of the doctor at the pre‑hospital stage is to organize the early delivery of a patient with suspicion of meningitis to the hospital. At the hospital stage, a lumbar puncture should be performed immediately (in the absence of contraindications) and antibiotics of a broad spectrum of action should be prescribed. Investigations of other liquids takes precedence when it is impossible to collect or analyze liquor. It is recommended to change swiftly the antibiotic therapy with broad spectrum drugs to specific ones or to other etiotropic treatment, depending on the results of the study of liquor. In addition, dexamethasone should be administered. Vaccination, isolation and mechanical protection are effective for the prevention, chemoprophylaxis is carried out in exceptional cases. Treatment of other types of meningitis is etiotropic and symptomatic.

A new silica-organic hybrid material with fixed ionic liquid 1-n-propyl-3-methylimidazolium chloride has been synthesized by the sol-gel method. Its specific surface area is 22 m2 g−1, average pore diameter is 8 nm and pore volume is 0.05 cm3 g−1. According to the results of 13C NMR spectroscopy, the fixed 1-n-propyl-3-methylimidazolium cationic group is bound with the siloxane framework via one Si C covalent bond. Properties of the new material were compared with that of its analog, silica with the same modifier covalently grafted at the surface. With the use of the 29Si NMR spectroscopy it was clearly indicated that at the surfaces of both materials silanol groups dominate among all silicon containing groups. The surface polarity was characterized by probing the materials with the solvatochromic Reichardt’s dyes, and the heterogeneous polarity of the near-surface layers has been detected. The values of the normalized Dimroth-Reichardt parameter for three surface regions of different polarities are 0.9–1.0, 0.65 and 0.4. The presence of rather acidic surface silanol groups revealed from probing these materials with solvatochromic dyes was verified with the application of acid-base fluorescent dyes of 2,5-diaryl-1,3-oxazole series having pKa 4.5–4.8 in ethanol/water medium. The fluorescence spectroscopy experiments have proved unambiguously that surface silanol groups predetermine the possibility of coexistence of the conjugated Bronsted basic and acidic forms of the oxazolic dyes in the near-surface layers.

Some fused aziridines are highly sensitive photochromes due to the presence of sterically strained three-membered ring. The study of photoinduced transformations of several such compounds in solutions, crystalline state, and polymeric and liquid crystal matrices using UV–vis and ESR spectrometry in combination with quantum chemical calculations revealed stepwise character of the transformations. The first deep-colored product was proven to be a new type of stable triplet biradical species while the second one was poor-colored azomethine ylide which had been previously considered as the species responsible for photochromism in crystalline state.

The purpose of the article is to decide the possibilities of Ukrainian financial security management in the conditions of military and political instability through adaptation of the indicators for the current methodology of the state financial security calculating in order to achieve the goals of sustainable development. The authors use general scientific and special methods, in particular dialectical, abstract logical, system analysis, economic and statistical. The authors in terms of the system approach and the allocation of material and information basis consider financial security. The authors formalize the process of informational support for the management of state financial security. Analysis of statistical data suggests that the determination of the Ukrainian financial security takes place because of political and military instability. Every component of financial safety includes factor of war influence, which as a result correlates the integral index of financial safety. The authors investigate factors that include expenditures for army forces support, aggressor state exchange rate expenditures, volume of monetary mass of the aggressor state in national economics, participation of the aggressor state capital in the banking capital structure, volume of financial resources loss of the aggressor-state.

The periodic gratings are effectively used for producing modern electronics and radio engineering equipment and complexes. The electromagnetic wave diffraction problem for cone gratings is considered. Impedance boundary conditions at cone structure are proposed. The problem of electromagnetic wave diffraction on cone gratings with imperfectly conducting strips is studied. Diagrams of electromagnetic field distribution are given.

The method for solving initial-boundary electromagnetic problems is proposed. It uses the Green’s function method and the Laplace and Meler-Fock integral transforms in a time domain. The model problem of special slotted cone antenna excitation is studied. Integral and series representation of electromagnetic field component are given.