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УДК 517.9 Отримано достатні умови існування кусково-неперервних майже періодичних розв'язків хвильового рівняння з затуханням та імпульсною дією.

Magnetotransport in mesoscopic samples with semiconductor artificial graphene has been simulated within the Landauer–Büttiker formalism. Model four-terminal systems in a high-mobility two-dimensional electron gas have a square shape with a side of 3–5 μm, which is filled with a short-period (120 nm) weakly disordered triangular lattice of antidots at the modulation amplitude of the electrostatic potential comparable with the Fermi energy. It has been found that the Hall resistance $${{R}_{{xy}}}(B)$$ in the magnetic field range of B = 10–50 mT has a hole plateau $${{R}_{{xy}}} = - {{R}_{0}}$$, where R0 = h/2e2 = 12.9 kΩ, at carrier densities in the lattice below the Dirac point n < n1D and an electron plateau $${{R}_{{xy}}} = {{R}_{0}}$$ at n > n1D. Enhanced disorder destroys the plateaus, but a carrier type (electrons or holes) holds. Long-range disorder at low magnetic fields suppresses quantized resistance plateaus much more efficiently than short-range disorder.

Ceftiofur is a third-generation cephalosporin used in veterinary medicine to treat infections caused by gram-negative and gram-positive bacteria. It is most often used in the form of suspensions for injections based on a lipid matrix, since the active substance is poorly soluble in water. The analysis of such a drug by direct spectrophotometry is difficult due to the components of the matrix, therefore it is proposed to develop a high-performance liquid chromatography method with UV detection. The aim of the work was to develop a method of identification and quantitative determination of ceftiofur hydrochloride in suspensions for injections. The method was developed and validated according to the indicators of selectivity, robustness, linearity and suitability parameters of the chromatographic system. Suspension for injections containing ceftiofur 50 mg/ml was used as a sample-object for method development. The standard sample and the test sample were dissolved in the mobile phase to a concentration of 50 μg/ml. The total uncertainty of the analysis was 1.62%, which is within the limits recommended in DFU 2.0. The samples were separated on a Dionex Ultimate 3000 chromatograph equipped with a Kinetex C18-XB 150×4.6, 5 μm chromatographic column. The mobile phase was a mixture of acetonitrile and 0.05 M ammonium acetate, 0.01 M tetrabutylammonium bromide with a pH of 6.8, titrated with acetic acid, in a volume ratio of 3:7. Ceftiofur hydrochloride was detected spectrophotometrically at a wavelength of 290 nm. Under the above conditions, it was possible to completely separate ceftiofur (retention time of the chromatographic peak – 4.4 min) and other components of the studied drug. At the same time, the suitability parameters of the chromatographic system did not exceed the limits specified in the recommendations of the USA Food and Drug Association. For the ceftiofur hydrochloride peak, the efficiency of the chromatographic system was 13,900 theoretical plates. The relative standard deviation (RSD) for the peak areas of the active substance was ±0.11 %, and the peak separation coefficient (RS) of ceftiofur hydrochloride from other components of the drug was 17.3. The symmetry coefficient of the peak was 1.02. The calibration curves were linear in the recommended DFU 2.0 range (80–120% of the nominal concentration of the corresponding active substance). The coefficient of linearity (R2) for the peak area of ceftiofur hydrochloride was 0.9992.

Food security includes not only the provision of basic foodstuffs to the population but also the guarantee of their quality and safety for the consumer. These criteria are essential for milk as the primary food product. The pathological processes, which are developed in the breast, harm the quality of milk, and the medical products used in their treatment, may affect the safety of this product. The article has represented the results of the bioregulatory approach in treating catarrhal mastitis in cows using medical products containing ultra-low doses of biologically active substances. These products do not have a withdrawal period regarding milk. The use of this approach makes it possible to increase the safety of treatment, which in turn will lead to economic benefits. Clinical symptoms of mastitis were determined by clinical signs (increasing local temperature, soreness, thickening of the udder, changing in color and consistency of milk, presence of flakes and clots). A сow No. 3095 was selected with characteristics of clinical symptoms of catarrhal mastitis of the rear left lobe of the udder. The following scheme was used for therapy: intramuscular injection of Traumeel 10 ml once a day, intracisternal injection of Lachesis Сompositum 10 ml into the affected part once a day, Traumeel(gel) locally after milking. The choice of bioregulatory preparations was based on the components and their action. On the third day, the cow's udder swelling decreased, local temperature normalized. The color and consistency of milk during control milking and its examination with the Avita diagnostic test showed an improvement from (+++) to (++). Complete clinical and laboratory recovery was diagnosed on the sixth day. A cow was returned to the general herd. Based on the treatment results, it can be concluded that this treatment scheme for catarrhal mastitis is effective. The absence of a withdrawal period regarding milk and the acceleration of recovery rates make it economically profitable.

Quantum transport has been simulated in hexagonal semiconductor lattices of antidots with a period of 80 nm and short-range disorder. Wannier diagrams, i.e., DoS(n, B) maps of the density of states, where n is the electron density and B is the magnetic field strength, have been calculated for several potential modulation amplitudes comparable to or much larger than the Fermi energy. Deep dips in the maps of the density of states have the form of rays with positive, zero, and negative slopes. In addition to the fan of the rays separating the first and second, as well as the second and third Landau levels, the maps include rays that are parallel to them and are shifted in n and B by integers of the characteristic electron density n0 and the characteristic magnetic field strength B0, respectively. It has been shown that the sign and magnitude of the slope of the rays in the density of states correspond to the centers of the plateaus of quantized Hall resistances Rxy. The lattice is brightly manifested in the Rxy(n, B) maps as the replicas of the first and second plateaus in Rxy and as oscillations of Rxy between negative and positive values at a fixed magnetic field or a fixed electron density, which indicates the interchange between the hole and electron charge carriers.

УДК 517.9Отримано умови частотної синхронiзацiї орбiтально асимптотично стiйкого перiодичного розв’язку системи автономних диференцiальних рiвнянь при малих iмпульсних збуреннях. Введено локальнi координати в околi стiйкого iнварiантного циклу i доведено iснування кусково-гладкого iнтегрального многовиду у збуреної iмпульсної системи.Для дослiдження поведiнки iмпульсної системи на збуреному многовидi i отримання умов синхронiзацiї застосовано метод усереднення iмпульсних систем.

Актуальность. Сахарный диабет 2 типа (СД 2) является глобальной проблемой для здравоохранения. Он связан с серьезными осложнениями, последствиями и повышенной смертностью. Несмотря на то, что за последние несколько десятилетий подходы к лечению СД 2 типа и его осложнений улучшились, растущая заболеваемость СД 2 типа подчеркивает необходимость инновационных подходов к его профилактике и лечению. Одним из неопределенных до конца направлений является участие витамина D в развитии и прогрессировании СД 2 типа. Цель: изучить влияние витамина D на возникновение и прогрессирование сахарного диабета 2 типа с помощью системного анализа доступных источников литературы. Материалы и методы. Системный анализ данных в базах Pubmed, Medline и EMBASE за 2005-2019 гг. по ключевым словам, относящихся к витамину D и сахарному диабету 2 типа одновременно. Результаты. Среди найденных 121 научных публикаций отобраны для дальнейшего анализа 22 исследования. Все исследования оценивали влияние витамина D на возникновение СД 2 типа. 10 исследований показали, что потребление витамина D в дозе > 500 МЕ в сутки снижает риск развития СД 2 типа по сравнению с потреблением витамина D в более низких дозах 25 нг/мл) имели более низкий риск развития СД 2 типа (95% доверительный интервал 24,57%) по сравнению с людьми с низким содержанием витамина D в сыворотке крови (

Актуальність. В процесі реформування охорони здоров’я України передбачається посилення профілактичної спрямованості в роботі сімейного лікаря, зокрема при боротьбі з хронічними неінфекційними захворюваннями (ХНІЗ), це приведе до посилення взаємодії інституції загальної лікарської практики/сімейної медицини і інституції медицини праці. Таким чином, актуальною є розробка інструментів, які дадуть змогу лікарям загальної практики – сімейної медицини проводити ефективні заходи з профілактики при роботі з трудовими колективами. Мета дослідження. Оптимізувати програми скринінгових профілактичних обстежень працівників лікарем загальної практики – сімейної медицини для покращання профілактики ХНІЗ в трудових колективах. Матеріали та методи. Розроблено багатоступеневу скринінгову програму, яка складалася з 3 етапів. Перший етап включав опитування за допомогою спеціально розробленої онлайн-анкети з оцінки факторів ризику і прогресування ХНІЗ та стану здоров’я працівника, другий етап – огляд сімейного лікаря, третій - консультація і обстеження у спеціалістів, в залежності від результатів попередніх етапів. У дослідженні приймали участь 83 працівники фармацевтичної компанії від 18 до 64 років (чоловіки 24%, жінки 76%). Задоволеність та якість медичного огляду оцінювалась анкетуванням. Аналіз даних та ефективності програми проводився за допомогою статистичних методів в Excel 2010. Результати. Аналіз даних онлайн-анкетувань, даних комплексного медичного огляду лікарем загальної практики сімейної медицини дав змогу оптимізувати час та методику проведення скринінгу і запропонувати пацієнторієнтовану пропозицію з мультидисциплінарним підходом, спрямовану на вирішення найбільш актуальних проблем кожного з працівників, що вплинуло на часову, медико-соціальну і економічну ефективність та прихильність до участі в програмі. Працівники вказали на достатню якість проведеної багатоетапної скринінгової програми і задоволеність профілактичним оглядом. Медико-соціальна ефективність проведеної програми становила 1,6. При оцінці економічної ефективності 1 і 2 етапів встановлено, що при запровадженні онлайн-анкетування відбулось скорочення тривалості профілактичного обстеження кожного працівника на 50%. Співвідношення показників вигоди/витрати (P) для 2 та 3 етапів скринінгової програми становило Р3>Р2 відповідно. Висновки. Багатоетапна програма скринінгового обстеження працівників з застосуванням онлайн опитувань, дала можливість зменшити час та вартість профілактичного медичного обстеження і відповідно збільшити економічну та медико-соціальну ефективність. Пацієнт-орієнтований підхід надав можливість визначити необхідний об’єм обстежень та процедур. Хоча пацієнти були більш прихильні до консультацій профільних спеціалістів, найбільш ефективними виявилась співпраця лікаря загальної практики – сімейної медицини з спеціалістами в мультидисциплінарній команді.

When generalizing the geometrically nonlinear law of Murnaghan elasticity to plasticity, a formally mathematical criterion was introduced for deformational macrofracture (macrocrack appearance) associated with an increase in elastic and plastic anisotropy as a failure cause. The use of the double potentiality of the governing equations in stresses and their velocities made it possible to obtain the reliable information on the structure of the deviatory section of the yield surface, the existence of which is a classical hypothesis in solid mechanics. The normal vector to the surface of the deviatory section is selected from two mutually orthogonal eigenvectors of the constructed operator. There are two families of regular concave surfaces, and a section surface is formed by joining the parts of two representatives of the families at singular points. To select normal vectors, the obtained ratio for them is used for isotropy. In connection with the considered problem of a double simple shift, it is established that multiple eigenvalues appear for the both normal vectors. To unambiguously determine the normal vector at a regular point, it is necessary to exclude the presence of multiple eigenvalues for the both normal vectors at the same time. At a singular point, the appearance of a multiple eigenvalue of one of the normal vectors is still unacceptable. These two conditions are necessary and sufficient to validate the governing equations of the generalized Murnaghan model. Otherwise, a macrocrack occurs. The theoretical construction is supported by the developed software complexes.

The aim of the study was to investigate the stability of diazinon in two model mixtures in which the active substance content is 10%. Methyl and isopropyl alcohols were used as a basis for the production of model solutions with diazinon. According to the recipe of model drugs, methyl or isopropyl alcohols make up about half of the content of drug components. The diazinon content was determined by reversed-phase high performance liquid chromatography (HPLC) on 3, 14 and 21 days for the model mixture with methyl alcohol and on 14 and 50 days for the mixture with isopropyl alcohol. A significant number of publications have been devoted to the study of the degradation of diazinon and other nonspecific organophosphorus pesticides under the influence of various factors. However, it remains relevant to study this process in mixtures of a certain composition, in particular in new veterinary drugs under development. This article presents a comparison of the results of determination the content of diazinon in model mixtures based on methyl and isopropyl alcohols. The analyzes were performed on a Knauer liquid chromatograph with a spectrophotometric detector equipped with a Luna® Omega Polar C 18 150 × 4.6 mm column filled with a 5 μm sorbent of Phenomenex particle size with a 4 × 3.0 mm universal C 18 protective column. Mobile phase: degassed mixture of acetonitrile: water in the ratio 65:35, flow rate 1.1 ml / min at a column temperature of 20 °C, detection at a wavelength of 245 nm, injection volume - 0.050 ml, time of one separation - 20 minutes. It was found that the content of diazinon on the 21st day of storage of the model mixture based on methyl alcohol is about 30 % of the applied, while on the 50th day of storage of the model mixture based on isopropyl alcohol – 97 %. As we found in previous studies, the use of methyl alcohol is a probable factor in the breakdown of diazinon in the drug. The appearance of the peak of one of the products of diazinon for 3 min of the chromatogram of solutions of the production experimental preparation and the model mixture made in the HPLC laboratory with the solvent methanol was noted. When replacing methanol with isopropanol, the chromatogram of the drug solution did not show the appearance of an additional peak, except for the peak identified as diazinon. The use of isopropyl alcohol does not reduce the concentration of diazinon in the model mixture, as in the case of methanol. The composition with isopropyl alcohol provides relative stability of the model mixture.

The aim of work was to develop a method for the identification and quantification of neomycin sulfate in intracisternal veterinary preparations. The method was developed and validated by: selectivity, linearity and suitability parameters of the chromatographic system. A four-component intracisternal drug with a 25 mg/g neomycin content was used as an object sample for method development. The standard sample and the test sample were dissolved in purified water to a concentration of 100 μg/ml, followed by derivatization with 9-fluorenylmethoxycarbonyl chloride at room temperature. The total uncertainty of the analysis was 1.62 %, which is within the limits recommended in SFU 2.0. The samples were separated on a Dionex Ultimate 3000 chromatograph equipped with an Acclaim C18 150 × 4.6.5 μm chromatographic column. The mobile phase was a mixture of acetonitrile and water in a volume ratio of 95:5. Neomycin sulfate was detected fluorescently at wavelengths λex - 254 nm, λem - 303 nm. Under the above conditions, it was possible to completely separate the two isoforms of neomycin (retention time of chromatographic peaks - 6.57 min and 6.98 min), 9-fluorenylmethoxycarbonyl chloride and other components of the study drug (retention time of the corresponding chromatographic peaks - 2-5 min). In this case, the parameters of the suitability of the chromatographic system did not exceed the limits specified in the recommendations of the USA Food and Drug Association. For peaks of neomycin sulfate, the efficiency of the chromatographic system was 7700–7950 theoretical plates. The relative standard deviation (RSD) for the peak areas of the active substance was ± 0.33%, and the coefficient of separation of the peaks (RS) of neomycin sulfate from the peaks of the derivatization reagent and other components of the drug was 11.9. The coefficient of peak symmetry was 1.18. The calibration curves were linear in the recommended SFU 2.0 range (80–120% of the nominal concentration of the corresponding active substance). The coefficient of linearity (R2) for the sum of neomycin sulfate peak areas was – 0.9991.

Creation of vascular grafts with atrombogenic and antimicrobial coating is a very important area.Objective: to evaluate the biocompatibility and antimicrobial properties of biodegradable vascular grafts of various polymer compositions with atrombogenic and antimicrobial drug coating.Materials and methods. Modification of the surface of the biodegradable vascular grafts was performed through complexation with polyvinylpyrrolidone, which was polymerized with polymer scaffold surface by means of ionizing radiation at 10 and 15 kGy. Physical and mechanical properties, as well as hemocompatibility were evaluated. Bacteriological studies were carried out using test strains of gram-negative and gram-positive microorganisms: Klebsiella pneumoniae spp. ozaena No. 5055, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Proteus mirabillis ATCC3177, Pseudomonas aeruginosa.Results. There was no influence of modifying manipulations with ionizing radiation on the physical and mechanical characteristics of biodegradable prostheses. Vascular grafts with atrombogenic and antimicrobial coatings exhibited atrombogenic properties upon contact with blood, reducing platelet aggregation by 5–7 times (p < 0.05). Also decrease in adhesion and platelets deformation index was found on the surface of drug-eluting scaffolds (for PCL-based prostheses, the latter decreased by 1.9 times relative to unmodified counterparts (p < 0.05), for PHBV/PCL-based prostheses – by 1.3 times relative to unmodified counterparts and 1.5 times relative to scaffolds with polyvinylpyrrolidone (p < 0.05). Bacteriological studies revealed a local inhibitory effect in the place where scaffolds with cationic amphiphile were applied on agar. No growth retardation zones were identified. Polymeric composition of the scaffolds and the used dose of ionizing radiation did not lead to a difference in the bacteriostatic properties of the scaffolds with amphiphile.Conclusion. A full cycle of surface modification of biodegradable polymer prostheses based on both PCL and РHBV/PCL composition resulted in significant increase in the atrombogenic and antimicrobial properties of prostheses and did not worsen the physical-mechanical and biocompatible properties of the structures being developed.

The low-frequency microwave photoconductance of a short (100 nm) quantum point contact based on a high-mobility two-dimensional electron gas in the frequency range of 2–3 GHz is investigated for the first time. The giant photoconductance in the tunneling regime and the negative photoconductance in the open regime are observed. It is shown by numerical simulations that such response to microwave irradiation is caused by the forced oscillations of the saddle-point potential in the quantum point contact and of the probe voltage applied to the contact.

Enzootic bovine leukosis caused by a bovine leukemia virus has a significant economic impact and is reported in World Organization for Animal Health(OIE). Aim. The purpose of our work was to improve the nested polymerase chain reaction (PCR) recommended by the OIE conducting it second-stage in real-time (RT) PCR. Such modification does not require the stage of gel electrophoresis and consequently reduces contamination risks and prevents false positive results. Methods. Primers that are recommended by the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals (OIE) were used for the first amplification stage. For the second stage of the proposed modification of nested PCR, the primers and probe were designed based on the alignment of the sequences envelope gene of different isolates of bovine leukemia virus including Ukrainian isolates. Amplification of the internal control was carried out for the second stage to prevent false negative results. Results. Comparative studies of 48 blood samples for bovine leukemia virus identification by a proposed nested RT-PCR, nested PCR recommended by the protocol of the OIE, and RT-PCR were conducted. The sample panel included both positive and negative samples. A 100% match of the results of the bovine leukemia virus presence in nested PCR proposed by the OIE and in our proposed nested RT-PCR was obtained. Comparative analysis of results that were obtained using the RT-PCR and the proposed nested RT-PCR showed that false-negative results in 5 samples and 3 doubtful results that require retesting were obtained by use of RT-PCR. The interpretation of the results using nested RT-PCR is more efficient than RT-PCR since the cycle threshold value of positive samples obtained using RT-PCR was in the range of 24–40 cycles, whereas in the case of nested RT-PCR using, the value of Ct was in the range of 4–20 cycles. Conclusions. Proposed nested PCR modification includes the combination of the OIE recommendation about nested PCR and the reduction of the risk of contamination by conducting the second stage in RT-PCR. Results of approbation of proposed nested RT-PCR give a reason to recommend it for the identification of bovine leukemia virus.

Habitual miscarriage is a stressful condition and a significant factor of frustration for married couples. The psycho-emotional state of the pregnant woman affects the course of the subsequent pregnancy and its outcome. Correction of the psychological component of habitual miscarriage is a promising direction for preventing reproductive losses. The aim of the work is to study the psychological components of miscarriage and determine the ways of their correction. Materials and methods. The level of chronic stress was studied in pregnant women with symptoms of miscarriage and a history of habitual reproductive losses (main group) based on indicators of psychoemotional state, the condition of the autonomic nervous system, and the degree of activation of stress-implementing systems. The results were evaluated with the scale PSS, PSM-25 as adapted by N. Ye. Vodopianova, Spielberger–Khanin inventory and the scale by L. D. Malkova, Baevsky index, cortisol content in the blood and urine. The pregnant women with a physiological course of pregnancy and uncomplicated history were included in the control group. Based on the fact that the etiology of habitual miscarriage is multifactorial, and the psychological component is amenable to correction, stress-protective therapy was included in the treatment complex of habitual miscarriage. To assess the effectiveness of treatment, the main group was divided into subgroups: 1 – with psychotherapy, 2 – without psychotherapy. Results. A high level of personal perception of stress, anxiety and asthenia determine the psycho-emotional state of the main group pregnant women, among whom two dominant psycho types were identified: A – a high level of anxiety and low neuropsychic resistance; B – poise and good adaptive ability against the background of stress. Non-drug stress-protective therapy in the complex of miscarriage treatment contributes to: a decrease in psycho-emotional stress in pregnant women with psycho type A – 2.6 times, anxiety level – 1.7 times, asthenia level – 2.3 times; and also: a decrease in similar indicators in pregnant women with psycho type B – 1.6 times, 3.9 times and 2.5 times, respectively (P < 0.05); a decrease in the frequency of premature termination of pregnancy by more than 11 %. Conclusions. The psychological component of miscarriage is a high level of personal perception of stress, anxiety and asthenia. Stress-protective therapy in combination with pathogenetic therapy of miscarriage improves pregnancy outcomes for the mother and the fetus. It is advisable to conduct pregravid training with the participation of a psychologist in women with a history of reproductive losses in order to overcome the psychological component of stress perception, expand adaptive potential, increase neuropsychic stability, and form a positive orientation toward pregnancy and motherhood.

The article is devoted to studying issues related to determining the impact of globalization processes on legal education. Issues that arise in solving the conceptual problems of educational processes in general and related to the development of educational technologies, economic learning processes and global migration. These trends can contribute to the global unity of national curricula, the internationalization of education and the achievement of the UN Sustainable Development Goals. The author examines the views of scientists on how educational needs change and transform because of the internationalization and technologization of educational processes. Have been determined the characteristics of the competencies that a future lawyer should have, taking into account the influence of globalization factors on the development of professional legal education. The formation of the competencies of the future lawyer, taking into account the impact of globalization on legal education, requires a change in approaches to teaching and learning. Innovative teaching methods are associated with the need for internationalization and technologization of educational processes, which allows you to form a professional with an active life position and communication skills of the future specialist in the field of law, in demand in the labor market. Of course, such approaches in legal education are based on the growing globalization of law and legal practice. The author concludes that innovative methods and technologies will contribute to the training of highly qualified and adapted to modern conditions specialists-lawyers, who will be in high demand in the labor market not only nationally but also globally. The author emphasizes the importance of the role of the lawyer in the formation of modern society.

An Erratum to this paper has been published: https://doi.org/10.1134/S0021364022390023

to investigate the morphological and immunohistochemical features of placental damage due to theincorporation of 137Cs depending on the scenario of pregnancy completion.The study material consisted of placentas from 60 women with reproductive losses inanamnesis and signs of termination of the current pregnancy (first group) and placental samples from 30 women with an uncomplicated gestation and an unencumbered anamnesis (control group). The detailed study required the distribution of placental samples from the first group into subgroups. Subgroup 1a included 38 placentas from women who gave birth at 37-40 weeks, despite signs of termination of the current pregnancy. Subgroup 1b - placentas of 13 women who gave birth at a gestation period of 28-36 weeks + 6 days. Subgroup 1c - 9 placental samples from women who gave birth at a gestation period of 22-27 weeks + 6 days. The volumetric activity of the 137Cs in the placentas was measured using β-spectrometer. The histology of the placenta was studied using a standard technique. The following expressions were studied in placenta: CD31 / PECAM-1, CD45 / T200 / LCA, CD56 / NCAM-1, CEA / CD66e Ab-2, Vimentin, using indirect streptavidin peroxidase detection method.Placentas accumulate 137Cs. The different volumetric activity of the isotope correlates with scenarios of pregnancy. Due to the action of incorporated 137Cs with a specific mass of more than 1.1 Bq/kg, placental dysfunction develops. The consequences of placental dysfunction depend on the volumetric activity of the 137Cs and the preservation of adaptive and compensatory reactions in the placenta. Morphological and immunohistochemical features of placental damage to incorporated 137Cs were established, depending on the scenario of completion of pregnancy. A marker of unfavorable completion of pregnancy is the expression of a carcinoembryonic antigen (CEA) in the placenta.Premature termination of pregnancy (PTP) is a multifactorial pathology associated with pathological changes in immune and neuroendocrine regulation and hereditary, infectious, and environmental factors that disrupt the adaptation mechanisms in the mother-placenta-fetus system. Intraplacental irradiation of 137Cs is one of the factors in the multifactorial nature of reproductive losses. As a result of intraplacental irradiation of 137Cs, the architecture of the placenta is disturbed, the activity of pro-inflammatory cytokines CD45 and CD56 increases, and the coagulation cascade is activated. Extreme effects depend on the volumetric activity of the isotope incorporated in the placenta and the organ's compensatory capacity. Accumulation of up to 1.0 Bq/kg 137Cs does not affect the course of gestation. Internal irradiation with an activity of 4.5-10.4 Bq/kg 137Cs triggers late preterm labor. The nature of the damages corresponds to the category of «lesion of the maternal stroma» of the placenta. The volumetric activity of 137Cs over 10.4 Bq/kg is a probable cause of early preterm labor and antenatal fetal death. At the same time, the maternal and fetal structures of the placenta suffer damage. Expression of vimentin is a marker of placental destruction due to internal irradiation of 137Cs with a specific gravity of more than 4.5 Bq/kg. Expression of CEA in the structures of the placenta of women with PTP is a unique find and marker of premature birth and antenatal fetal death with intraplacental irradiation of 137Cs with an activity of more than 4.5 Bq/kg.Meta: doslidyty morfologichni ta imuno-gistokhimichni osoblyvosti urazhennia platsenty vnaslidok inkorporuvannia 137Cs zalezhno vid stsenariiu zavershennia vagitnosti. Materialy ta metody. Material doslidzhennia – platsenty 60 zhinok z reproduktyvnymy vtratamy v anamnezi taoznakamy pereryvannia potochnoï vagitnosti (osnovna grupa) i platsenty 30 zhinok z neuskladnenym perebigomvagitnosti ta neobtiazhenym anamnezom (kontrol'na grupa). Dlia detal'nogo analizu zrazky platsenty osnovnoïgrupy podilyly na pidgrupy. Do pidgrupy 1a uviĭshly 38 platsent vid zhinok, iaki narodyly v termini 37–40 tyzhniv,nezvazhaiuchy na oznaky pereryvannia potochnoï vagitnosti. Pidgrupa 1b – platsenty 13 zhinok, iaki narodyly v termini vagitnosti 28–36 tyzhniv + 6 dniv. Pidgrupa 1c – 9 zrazkiv platsenty vid zhinok, iaki narodyly v termini vagitnosti 22–27 tyzhniv + 6 dniv. Ob’iemnu aktyvnist' inkorporovanogo 137Cs u platsenti vyznachaly za dopomogoiu β-spektrometriï. Gistologichne doslidzhennia platsenty provodyly za standartom. U platsenti doslidzhuvaly taki ekspresiï: CD31/PECAM-1, CD45/T200/LCA, CD56/NCAM-1, CEA/CD66e Ab-2, Vimentin, vykorystovuiuchy nepriamyĭmetod vyiavlennia streptavidynperoksydazy.Rezul'taty. Vstanovleno, shcho platsenty nakopychuiut' 137Cs. Rizna ob’iemna aktyvnist' izotopu koreliuie zi stsenariiamy vagitnosti. Vnaslidok diï inkorporovanogo 137Cs z pytomoiu masoiu ponad 1,1 Bk/kg rozvyvaiet'sia platsentarna dysfunktsiia. Naslidky platsentarnoï dysfunktsiï zalezhat' vid ob’iemnoï aktyvnosti 137Cs i zberezhennia adaptatsiĭno-kompensatornykh reaktsiĭ u platsenti. Zalezhno vid stsenariiu perebigu vagitnosti vstanovleno morfologichni ta imunogistokhimichni osoblyvosti urazhennia platsenty inkorporovanym 137Cs. Markerom nespryiatlyvogozavershennia vagitnosti ie ekspresiia rakovo-embrional'nogo antygenu (REA, CEA) v platsenti.Vysnovky. Nevynoshuvannia vagitnosti (NV) tse mul'tyfaktorna patologiia, pov’iazana z patologichnymy zminamyimunnoï ta neĭroendokrynnoï reguliatsiï, spadkovymy, infektsiĭnymy ta ekologichnymy faktoramy, iaki porushuiut'adaptatsiĭni mekhanizmy v systemi «maty–platsenta–plid». Intraplatsentarne oprominennia 137Cs – odyn iz chynnykiv u bagatofaktorniĭ pryrodi reproduktyvnykh vtrat. Vnaslidok vnutrishn'oplatsentarnogo oprominennia 137Cs porushuiet'sia arkhitektura platsenty, pidvyshchuiet'sia aktyvnist' prozapal'nykh tsytokiniv CD45 ĭ CD56, aktyvuiet'sia kaskad koaguliatsiï. Ekstremal'ni efekty zalezhat' vid ob’iemnoï aktyvnosti inkorporovanogo v platsenti izotopu ta kompensatornoï spromozhnosti organu. Nakopychennia do 1,0 Bk/kg 137Cs ne vplyvaie na perebig gestatsiï. Vnutrishnie oprominennia z aktyvnistiu 4,5–10,4 Bk/kg 137Cs vystupaie trygerom piznikh peredchasnykh pologiv. Kharakter poshkodzhen' nalezhyt' do kategoriï «Urazhennia materyns'koï stromy». Ob’iemna aktyvnist' 137Cs ponad 10,4 Bk/kg -ĭmovirna prychyna rannikh peredchasnykh pologiv ta antenatal'noï zagybeli ploda. V ts'omu vypadku, poshkodzhennia zaznaiut' materyns'ki ta plodovi struktury platsenty. Ekspresiia vimentynu – marker platsentarnoï destruktsiïvnaslidok vnutrishn'ogo oprominennia 137Cs pytomoiu masoiu ponad 4,5 Bk/kg. Ekspresiia REA v platsentakh zhinok zNV – unikal'na znakhidka i marker peredchasnykh pologiv ta antenatal'noï zagybeli ploda pry vnutrishn'oplatsentarnomu oprominenni 137Cs pytomoiu masoiu ponad 4,5 Bk/kg.

The paper presents the results of studies of the structure and physical and mechanical properties of copper M0b after combined plastic deformation under different schemes of equal channel angular pressing (ECAP) and upsetting or ECAP and multi upsetting. Comparative characteristics of the structure, hardness and deformational decompaction of copper are given. Interesting to note that after ECAP and multi upsetting treatment, a deeper development of the structure has been observed.

The aim of the work was to develop and validate a method for the simultaneous identification and quantification of dihydrostreptomycin and benzylpenicillin in injectable suspensions. The method was validated by testing two preparations in the form of injectable suspensions containing benzylpenicillin 108–144 mg/ml and dihydrostreptomycin 180–220 mg/ml. Test samples were dissolved in purified water P, and standard samples: benzylpenicillin - in methanol (up to a concentration of 126 μg/ml), dihydrostreptomycin - in purified water P (up to a concentration of 200 μg/ml). The maximum allowable total uncertainty of the analysis was 1.64%, which is within the recommendations of SFU 2.0. The samples were separated on a Dionex Ultimate 3000 chromatograph equipped with a Luna C18 (2) 250 × 4.6 mm, 5 μm chromatographic column. The mobile phase was a mixture of acetonitrile and a solution of 0.01 M sodium heptanesulfonate with 0.05 M sodium phosphate trisubstituted, acidified with 0.1 M phosphoric acid to pH 6.0, in a volume ratio of 2: 8. Under mentioned conditions, dihydrostreptomycin and benzylpenicillin were completely separated. The established parameters of the chromatographic system did not exceed the limits specified in the FDA recommendations. The calibration curves were linear in the recommended SFU 2.0 range (80–120% of the nominal concentration of the corresponding active substance). The ratio of the amount of standard sample added to the test samples with its subsequent detection in the preparation was 99.35–100.79% for benzylpenicillin and 99.49–100.12% for dihydrostreptomycin, which does not exceed the limits recommended in SFU 2.0. The precision criterion was 0.07 for dihydrostreptomycin and -0.08 for benzylpenicillin, which is within the limits recommended in SFU 2.0. At the same time, the results of the study by different analysts at different times differed by 1.3% for dihydrostreptomycin and 0.98% for benzylpenicillin, which is well within the limits adopted in the recommendations of the FDA and SFU 2.0. Therefore, the method developed and validated by us for the simultaneous determination of dihydrostreptomycin sulfate and benzylpenicillin procaine in injectable suspensions can be considered suitable for routine analysis.

Мета: дослідити можливості Реєстру хворих на хронічні вірусні гепатити в Дніпропетровському регіоні як спостережної програми та інструменту моніторингу і менеджменту за пацієнтами. Матеріали і методи. Аналіз поширеності хронічних вірусних гепатитів проведено епідеміологічним методом. У роботі застосовано методи дескриптивної статистики, статистичний метод та метод структурно-логічного аналізу з використанням програмних продуктів Excel і Statistica v.6.1. Результати. Проведено оцінку дієвих реєстрів пацієнтів в Україні, обрано найкращі практики та адаптовано, оптимізовано і впроваджено в Реєстр хворих на хронічні вірусні гепатити дорослого віку та дітей в Дніпропетров­ському регіоні. Обґрунтовано доцільність його використання як дослідного інструменту при менеджменті 4699 хворих на хронічні вірусні гепатити В та С віком понад 18 років та 195 дітей. Оцінено ефективність різних схем лікування. Висновки. Десятирічний досвід ведення Реєстру дозволив оцінити тяжкість хронічних вірусних гепатитів у Дніпропетровському регіоні, здійснювати моніторинг населення, ураженого хронічними вірусними гепатитами, проводити аналіз динаміки та прогностичну оцінку визначених показників ризику прогресування хвороби в різних клінічних групах хворих, контролювати якість та ефективність лікування, повноту та режим динамічного нагляду за хворими. Запропоновано імплементувати досвід для створення Реєстру та персоніфікованого автоматизованого обліку хворих на хронічні вірусні гепатити в Україні.

By using the properties of asymptotically almost periodic solutions, we establish conditions for the existence of a positive asymptotically stable piecewise continuous and almost periodic solution of the logistic equation with almost periodic coefficients and nonfixed times of impulsive action.

Studies of photon-stimulated transport through a quantum point contact based on a high-mobility two-dimensional electron gas in a GaAs quantum well are reviewed. This review includes a brief historical introduction, experimental results on giant terahertz and microwave photoconductance of the quantum point contact in the tunneling regime, and the analysis of its behavior within a developed theoretical model of photon-stimulated tunneling. Prospects of further studies and production of a new class of terahertz and microwave detectors are discussed in closing.

—A pulsed power supply based on capacitive storage with a partial discharge for high-frequency pulsed linear electron accelerators of the ILU type is described. The maximum output pulse voltage of the source is 36 kV at a load current of up to 250 A and a pulse duration of up to 1 ms, and a pulse repetition rate of up to 100 Hz. The source is built according to a relatively simple modular scheme and consists of ten modules connected in series. It was assembled and tested with a load connection in one module. The circuit provides uniform current consumption in all phases of a 380 V three-phase supply network.

Lithium salt of binuclear ruthenium nitride complex Li3[Ru2NCl8 · 2H2O] has been synthesized. Structure of the complex was studied by X-ray diffraction. Triclinic crystals, space group P $$\bar {1},$$ a = 7.4044 A, b = 8.1818 A, c = 8.7123 A, α = 117.970°, β = 115.139°, γ = 90.014°, V = 408.65 A3, Z = 1, ρcalcd = 2.654 g/cm3. The complex is thermally stable, it dimerizes in acid medium to give tetranuclear cluster $${\text{R}}{{{\text{u}}}_{{\text{4}}}}{{{\text{N}}}_{{\text{2}}}}{\text{O}}_{{\text{5}}}^{ + }$$ , an active catalyst of four-electron oxidation of water to form O2. Catalyst efficiency in the reaction of water oxidation (TON) reaches 356 over 1 h.

Experimental results obtained on the synthesis, in a cubic apparatus, of composites based on diamond-like boron nitride cBN in the system cBN–Al–TiC are presented. It is shown that for the optimal ratio of the number, size, and relative arrangement of the particles of superhard material and a nanostructured binder high-level properties can be attained without the obligatory intergrowth of particles of superhard crystals cBN–cBN. The composites were sintered at pressure 4.5 GPa and temperature 1450°C. The chosen thermobaric parameters guaranteed complete reactive interaction, homogeneity of the phase composition, and uniformity of the physicomechanical characteristics throughout the entire volume of large-size composites.

The control and protection systems that have made it possible to create a unique 3-modulator pulse power supply for the ILU-14 accelerator are described. Attention is also paid to the development of electronic and software tools that allowed the expansion of the field of application of a powerful electron accelerator with energies up to 10 MeV in industry. The accelerator is the main element of an industrial irradiation complex that processes medical and industrial products.

The article proposes a model for evaluating the activities of retail enterprise, which is based on five stages and allows determining ways to increase the efficiency of functioning, which will improve the adaptive properties of the economic object. The analysis of types of KPI is carried out, process and functional approaches are identified as the main ones for the direct development of key performance indicators, as well as the characteristics of the evaluation of effective marketing at enterprises, including those that function in the sphere of retail trade, are determined. The authors considered how modeling and forecasting of key financial indicators of an enterprise contribute to the creation of strategies for its development. The article notes that for the initial evaluation of a retail enterprise focused on long-term success, it is mandatory to conduct an audit aimed at assessing the efficiency of the economic object and defining how quickly the enterprise adapts to dynamic environmental conditions. The carried out analysis allowed to identify the key factors that contribute to an improvement of the enterprise’s operation. Also, on the example of the Isikawa diagram, the ratio of KPI, strategies and understanding of business processes was considered in order to set, control and analyze the achievement of goals.

This paper presents the results of mathematical and physical modeling of the interaction of waves with the wave chamber on cylindrical supports and the upper part in the form of a permeable waterfront. On the basis of the diffraction model the mathematical modeling of refraction and transformation of waves near the structure is carried out. In the presence of a structure, the transformation of waves is co-accompanied by the phenomena of wave destruction at the edges of the structure and the partial reflection of residual waves from the walls of the protective front. Reflection phenomena cause changes in wave heights along the front of the structure. The results of experimental data are given, which showed that the structure with such a construction is resistant to waves, large soil erosion was not observed.