3,590 results on '"Voitenko, A."'
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2. Investigation of Spectral Parameters of Constricted arc Plasma for Controlling Welding Processes and Related Technologies
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Valeriy Chernyak, Volodymyr Korzhyk, Shiyi Gao, Vladyslav Khaskin, Oleksandr Voitenko, Yevhenii Illiashenko, Xinxin Wang, Andrii Grynyuk, Oksana Konoreva, and Iryna Sviridova
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welding ,arc plasma ,spectral parameters ,welding and related technologies ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The paper is devoted to investigation of spectral parameters of constricted arc plasma, as a foundation for further development of basic approaches to intellectual controlling of plasma-arc technologies of material treatment and welding. The relevance of application of spectrometric analysis of the welding arc consists in obtaining the possibility of sufficiently accurate control of its temperature and energy input into the product being welded, recording initiation of weld defects (including internal pores), determination of atmospheric oxygen ingress into the weld pool, etc. The spectral composition, temperature and concentration of the constricted welding arc plasma were determined in the paper to more precisely define its physical characteristics at 80 and 100 A currents, in order to establish the further applicability of dynamic spectral analysis of a constricted plasma arc in control of welding processes. As modern spectrometers with CCD-detectors of the spectral range of 200÷1100 nm have the resolution of the order of 0.35 nm, which 2-3 times exceeds the quantization step by the measured wavelength, and may lead to considerable errors, an approach is proposed to increase the accuracy of spectrometric measurements to acceptable values. Radiation spectra of the constricted welding arc measured in the wavelength range of 650÷1000 nm allowed within the model of local thermodynamic equilibrium calculating the excitation temperature of the main spectral range components: Ar I and O I. It was established that the excitation temperature of electron levels of Ar atoms in the welding arc plasma only weakly depends on the discharge current, and it is equal to 13500 ± 500 K. Excitation temperature of O I electron levels was equal to 10000 ± 500 К at arc current of 100 A and to 7200 ± 500 К at 80 A current. Electron density of high-current welding arc plasma was measured by Stark broadening of Ar I lines (696.543; 772.4; 912.3 nm). It was found that with the rise of current of the constricted welding arc by 20%, an increase of charge concentration in the arc plasma by 1.5 times and of its temperature by 1.2 times are observed.
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- 2024
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3. Expert assessment of competitive activities of highly qualified field hockey players
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Viktor Kostiukevych, Tetiana Vozniuk, Maxim Perepelytsia, Viktoriia Bohuslavska, Sergey Voitenko, and Natalia Svirshchuk
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field hockey ,olympic qualification 2024 ,selection and ball ownership phases ,fielders ,management influences ,Sports ,GV557-1198.995 - Abstract
the most effective types of control over competitive activities is expert evaluation. Purpose of the study is to develop a methodology for expert assessment of competitive activities of highly qualified field hockey players. Material and methods. The study involved 16 highly qualified field hockey players, aged from 19 to 37 years. The average age of the players is 27.3±5.06 years. Sports Qualification: Master of sports of Ukraine. All players were given informed consent to participate in the study. The study was conducted in 2024 during the 2024 Olympic field hockey qualification competition (the city of Valencia, Spain). The research was carried out on the basis of the following methods: theoretical analysis and generalization of scientific and methodological literature; pedagogical observation; video recording of competitive activities; method of expert assessments; methods of Mathematical Statistics. Results. The author's methodology for expert assessment of competitive activity of field hockey players has been developed based on a 10-point scale, consisting of 5 criteria in the ball ownership phase and 5 criteria in the ball picking up phase. Each of the criteria is rated from 1 to 10 points. The fluctuation of the average values of the expert assessment of players of the national team of Ukraine in the matches of the Olympic qualification 2024 is in the range from 4.2±0.45 to 6.6±0.49 points. Conclusions. The developed methodology of expert assessment of competitive activity of highly qualified field hockey players is appropriate for effective management influences in the process of competitive activity of club and national teams in the Olympic sport – field hockey.
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- 2024
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4. Assessment of earthquake resistance of critical infrastructure objects, taking into account their own harmonics in the explosive spectrum of civil and military characters
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V.V. Boiko, Yu.I. Voitenko, A.L. Han, T.V. Khlevniuk, Ye.A. Zahoruiko, and O.V. Han
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civil and military explosion ,critical infrastructure ,laplace and fourier transforms ,elastic waves ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The article presents theoretical and experimental studies of the patterns of repeatability of seismic waves excited by man-made explosions to assess the earthquake resistance of critical infrastructure objects. The nature of propagation of wave perturbations at the boundary of an elastic half-space during its local excitation is theoretically considered. These studies are based on the integral Laplace and Fourier transformations, the numerical solution of which makes it possible to obtain the values of the repetition periods of elastic wave perturbations at the half-space boundary. On the basis of theoretical studies, the regularity of periods of repetition of perturbations of elastic waves is established, which under certain conditions can create resonant phenomena in protected objects, in particular at a harmonic close to the frequency of natural vibrations of the structure. Confirmation of these results in practice was obtained when critical infrastructure was hit by missile strikes (Kyiv TV tower tower) and in the conditions of blasting operations at quarries, as an example at the Koshchiivske granite quarry of LLC "SIPAN" when assessing the earthquake resistance of critical infrastructure objects, in particular the supports of 330 kW power lines, which are located in the zone of influence of elastic waves. They are based on the formation of patterns of excitation and propagation of elastic waves and determination of their parameters at a distance from the source of excitation (mass explosions at the quarry) using a hardware complex of standard seismic sensors SM-3, a 16-channel analog-to-digital converter (ADC E14-440) of L-Card and a personal computer (PC). Assessment of the influence of the intensity of seismic explosion waves was carried out at the frequency of the amplitude of the maximum speed of vibrations both at the base of the support, which is the norm of seismic safety in accordance with DSTU 4704:2008 and in the structure of the support itself (which is not mandatory in accordance with DSTU 4704:2008). But the presence of harmonics in the explosive spectrum that is close to the natural vibrations of the structure leads to the formation of resonant phenomena in it, which leads to an increase in the speed of vibrations in the structure itself than in the base of the support. Therefore, the maximum speed at a frequency close to its own vibrations or at the base of the support or on its structure is taken as a criterion of seismic safety. Such a wave parameter will best correlate with damage or harm to this structure and was proposed as the norm of its earthquake resistance. The research results obtained in this way prompted the authors to propose a supplement to the current DSTU.
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- 2024
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5. On optimal designs of cumulative charges of deep penetration
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Yu.I. Voitenko, S.V. Goshovskii, Yu.M. Sydorenko, and A.M. Pasitshnik
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shaped charge jet ,liner ,detonation ,shaped charge ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Abstract Purpose. Generalization of the results of the author's research on the influence of the shape of the liner on the mass-kinetic characteristics of the jets, the determination of the ways of the final optimization of the design of the charge, the analysis of the combined effect of the shape and liners materials on the efficiency of the charges Method. The methodological basis of research is a systematic approach to the problem of increasing the efficiency of a cumulative explosion. In accordance with the specifics of research aimed at achieving the set goals and obtaining technological dependencies, physical and mathematical modeling were used in the work. Findings. The results of a comparison of the parameters of the functioning of shaped charges with three forms of liners are presented: conical with an angle at the top of 2α=42º of constant thickness, progressive thickness with an angle at the top of 42º/43º, biconical with angles at the top and base of 38º/50º and 35º/50º and semi-elliptical. In some cases, different detonation excitation schemes were simulated. From a point on the axis of symmetry and around a circle with a diameter equal to the caliber of the charge. A comparison of the simulation results with the data of experimental studies for a short semi-elliptical liner. The results of the penetration depth of shaped charges jets into the barrier according to the A-V model (Allison and Vitali) were compared for a standard charge (2α=42º), biconical and semi-elliptical liners. Originality. Bi-conical and elliptical liners are promising forms of liners of shaped charges of deep penetration, which make it possible to form shaped charges jets that move at velocity greater than the velocity of the jet when detonating a standard shaped charges blow up with a conical liner. As the angle at the top of the conical liner decreases, the instability of the functioning of industrial charges increases and the spread of the penetration depth of the target increases Practical implications. The obtained results are important and useful for the design of equipment and technologies in various fields where the energy of a directed explosion is used: for the disposal and disposal of ammunition, for the opening of oil and gas reservoirs, for the reconstruction of construction facilities, in military affairs.
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- 2024
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6. IMPLEMENTATION OF THE RULE OF LAW PRINCIPLE IN THE PRACTICE OF UKRAINE: CONCEPT, STRATIFICATION AND ECONOMIC JUSTIFICATION
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Nataliia Bilak, Yuliya Voitenko, and Iryna Kozii
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rule of law principle ,principles of functioning ,legal framework ,penitentiary bodies ,penal system ,justice ,judicial practice ,international standards ,mechanism of application ,public associations ,public organisations ,economic security ,potential ,investments ,Economic growth, development, planning ,HD72-88 - Abstract
The subject of the study is the segmental manifestation of the rule of law principle and its elements in the activities of justice authorities, courts and public associations, taking into account the economic basis of its influence. The purpose of the study is to examine the forms of manifestation of the rule of law principle and its individual elements in the activities of justice and court authorities, to clarify the role of the public in its practical application, and to identify opportunities for its economic support. Methodology. The study used general scientific and special methods of scientific knowledge: the method of system analysis, the dialectical method, the formal logical method, the structural and functional method, as well as a number of empirical methods. In particular, the method of comparison was used to determine the transformation of penitentiary bodies and their transformation into penitentiary justice bodies. The results of the study demonstrated the need for: qualitative consideration of the aspect of ensuring the correction of a convicted person after serving his or her sentence; involvement of representatives of civil society institutions in the resocialisation processes; and identification of potential ways to implement effective reforms that can increase the efficiency and fairness of the judiciary. Conclusion. The article reveals the relationship between the transformation of the penal system into the penitentiary system and the implementation of the rule of law in this area and its comprehensive enforcement. It is noted that the criminal executive system takes into account the aspect of ensuring the serving of sentences, and in the penitentiary system, which operates under the rule of law, the authors additionally identifies such a qualitative component as ensuring the correction of a convicted person after serving his/her sentence and his/her resocialisation. It was found that the economic rationale for the transformation of the judiciary based on the rule of law consists in reducing the costs of: court functioning due to the possibility of digitalization of the preparatory stages before the court hearing and the holding of court hearings in videoconference mode; reducing costs for the court apparatus through optimization of its functions; reducing the number of court cases due to active mediation and other possible options for resolving disputes peacefully, etc. It is noted that justice in judicial proceedings means not only formal compliance with the law, but also the exercise of rights and freedoms of individuals with due regard for equality, objectivity and impartiality. The authors prove that non-governmental organisations are an important institution capable of promoting the principle of justice as an integral element of the rule of law, since they ensure the right to apply to court and the right to protection of members and third parties. The role of the public in shaping the economic basis for reforms and the proper functioning of state bodies was also highlighted. It is noted that national legislation needs to be amended in terms of granting NGOs the right to apply to court in the interests of third parties, in particular, in cases where a person is unable to protect his or her rights for valid reasons. The study analyses the fundamental provisions on economic support for the implementation of the rule of law in various spheres of public relations.
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- 2024
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7. Quantification of 11 metabolites in rat urine after exposure to organophosphates
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Michael A. Leninsky, Vladislav E. Sobolev, Margarita O. Sokolova, Natalya G. Voitenko, and Nikita V. Skvortsov
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Organophosphates ,Poisoning ,Rat ,Metabolites ,Urine ,Paraoxon-ethyl ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background The aim of the study was to develop a technique for quantitative determination of rat urine metabolites by HPLC–MS/MS, which can be used to search for biomarkers of acute intoxication with organophosphates (OPs). Results The content of metabolites in the urine of rats exposed to a single dose of paraoxon (POX1x); interval, twice daily administration of paraoxon (POX2x); exposure to 2-(o-cresyl)-4H-1, 3, 2-benzodioxaphosphorin-2-oxide and paraoxon (CBPOX) was investigated. New data were obtained on the content in the urine of intact rats as well as rats in 3 models of OP poisoning: 3-methylhistidine, threonine, creatine, creatinine, lactic acid, acetylcarnitine, inosine, hypoxanthine, adenine, 3-hydroxymethyl-butyrate and 2-hydroxymethyl-butyrate. Conclusions The proposed assay procedure is a simple and reliable tool for urine metabolomic studies. Within 1–3 days after OP exposure in all three models of acute intoxication, the concentration of metabolites in rat urine, with the exception of adenine, changes similarly and symmetrically, regardless of the method of poisoning modeling, in all three models of acute intoxication. Further studies are needed to determine the specificity and reliability of using urinary metabolite concentration changes as potential biomarkers of acute organophosphate intoxication. Graphical Abstract
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- 2024
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8. On Impact of Video Motion on Image Encryption/Decryption. Comparative Results.
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Anastasiia Voitenko and Mourad Oussalah 0002
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- 2024
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9. Approach for Electrophysiological Studies of Spinal Lamina X Neurons
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Krotov Volodymyr, Pavel Belan, and Nana Voitenko
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Biology (General) ,QH301-705.5 - Abstract
Despite playing diverse physiological roles, the area surrounding the central canal, lamina X, remains one of the least studied spinal cord regions. Technical challenges and limitations of the commonly used experimental approaches are the main difficulties that hamper lamina X research. In the current protocol, we describe a reliable method for functional investigation of lamina X neurons that requires neither time-consuming slicing nor sophisticated in vivo experiments. Our approach relies on ex vivo hemisected spinal cord preparation that preserves the rostrocaudal and mediolateral spinal architecture as well as the dorsal roots, and infrared LED oblique illumination for visually guided patch clamp in thick blocks of tissue. When coupled with electric stimulation of the spared dorsal roots, electrophysiological recordings provide information on primary afferent inputs to lamina X neurons from myelinated and non-myelinated fibers and allow estimating primary afferent–driven presynaptic inhibition. Overall, we describe a simple, time-efficient, inexpensive, and versatile approach for lamina X research.
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- 2024
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10. Initiation of Alfv\'enic turbulence by Alfven wave collisions: A numerical study
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Shestov, S. V., Voitenko, Y. M., and Zhukov, A. N.
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Astrophysics - Solar and Stellar Astrophysics ,Physics - Plasma Physics ,Physics - Space Physics - Abstract
In the framework of compressional magnetohydrodynamics (MHD), we numerically studied the commonly accepted presumption that the Alfv\'enic turbulence is generated by the collisions between counter-propagating Alfv\'en waves (AWs). In the conditions typical for the low-beta solar corona and inner solar wind, we launched two counter-propagating AWs in the three-dimensional simulation box and analyzed polarization and spectral properties of perturbations generated before and after AW collisions. The observed post-collisional perturbations have different polarizations and smaller cross-field scales than the original waves, which supports theoretical scenarios with direct turbulent cascades. However, contrary to theoretical expectations, the spectral transport is strongly suppressed at the scales satisfying the classic critical balance of incompressional MHD. Instead, a modified critical balance can be established by colliding AWs with significantly shorter perpendicular scales. We discuss consequences of these effects for the turbulence dynamics and turbulent heating of compressional plasmas. In particular, solar coronal loops can be heated by the strong turbulent cascade if the characteristic widths of the loop substructures are more than ten times smaller than the loop width. The revealed new properties of AW collisions have to be incorporated in the theoretical models of AW turbulence and related applications., Comment: 9 pages, 9 figures
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- 2022
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11. Strong europium luminescence in lanthan-euripium-erbium-calcium-vanadate nanocrystals, the result of codoping optimization
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Chukova, O., Nedilko, S. A., Nedilko, S. G., Voitenko, T., Slepets, A., Androulidaki, M., Papadopoulos, A., Stratakis, E., and Paszkowicz, W.
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Condensed Matter - Materials Science - Abstract
Co-doped with calcium, europium and erbium ions lanthanum vanadate crystalline nanoparticles are synthesized and investigated with a goal to clarify the mechanisms of calcium and erbium impurities effects on europium ions luminescence and to find compositions with enhanced luminescence intensity. The XRD analysis reveals dependence of crystal structure on dopants concentration: monoclinic crystal phase is observed for low dopant concentrations and content of tetragonal crystal phase increases with dopant concentrations increase. The SEM investigation reveals formation of nanoparticles with two types of shapes. Photoluminescence spectra consist of lines caused by inner transitions in the erbium and europium ions. It has been shown that dependence of the europium ions luminescence intensity on the calcium and erbium concentrations is caused by cumulative effects of dopants on crystal lattice structure, on defects in the first coordination sphere of the europium ions and on efficiency of excitation energy transfer.
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- 2022
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12. Decay characteristics of dense high-voltage pulse plasma discharges in water initiated by the electric explosion of iron conductor
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O. A. Fedorovich, L. M. Voitenko, V. V. Hladkovskyi, and O. V. Hladkovska
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dense plasma ,electrons concentration ,decay coefficient ,pulse discharge in water ,radiation spectra ,impurities of metal atoms ,spectrum sweeps ,dynamics of optical spectra. ,Atomic physics. Constitution and properties of matter ,QC170-197 - Abstract
The article presents the results of investigations of the decay coefficients of dense plasma in impulse discharges in water initiated by an electric explosion of an iron conductor. An analysis of time-resolved and spatial emission spectra of the discharges was performed, along with the study of absorption spectra dynamics with a 5 μs interval. The electron concentration of the dense plasma was determined at different time points, allowing the determination of its decay coefficients at electron concentrations ranging from 1020 to 1021 cm-3. It was found that under equal electron concentrations in the plasma, the decay coefficients of plasma with iron impurities are consistent with the decay coefficients of plasma with tungsten impurities.
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- 2023
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13. Testing Green Tea Extract and Ammonium Salts as Stimulants of Physical Performance in a Forced Swimming Rat Experimental Model
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Ekaterina A. Korf, Artem V. Novozhilov, Igor V. Mindukshev, Andrey S. Glotov, Igor V. Kudryavtsev, Ekaterina V. Baidyuk, Irina A. Dobrylko, Natalia G. Voitenko, Polina A. Voronina, Samarmar Habeeb, Afrah Ghanem, Natalia S. Osinovskaya, Maria K. Serebryakova, Denis V. Krivorotov, Richard O. Jenkins, and Nikolay V. Goncharov
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forced swimming ,endurance ,rats ,m. soleus ,m. extensor digitorum longus ,green tea extract ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The study of drugs of natural origin that increase endurance and/or accelerate recovery is an integral part of sports medicine and physiology. In this paper, decaffeinated green tea extract (GTE) and two ammonium salts—chloride (ACL) and carbonate (ACR)—were tested individually and in combination with GTE as stimulants of physical performance in a forced swimming rat experimental model. The determined parameters can be divided into seven blocks: functional (swimming duration); biochemistry of blood plasma; biochemistry of erythrocytes; hematology; immunology; gene expression of slow- and fast-twitch muscles (m. soleus, SOL, and m. extensor digitorum longus, EDL, respectively); and morphometric indicators of slow- and fast-twitch muscles. Regarding the negative control (intact animals), the maximum number of changes in all blocks of indicators was recorded in the GTE + ACR group, whose animals showed the maximum functional result and minimum lactate values on the last day of the experiment. Next, in terms of the number of changes, were the groups ACR, ACL, GTE + ACL, GTE and NaCl (positive control). In general, the number of identified adaptive changes was proportional to the functional state of the animals of the corresponding groups, in terms of the duration of the swimming load in the last four days of the experiment. However, not only the total number but also the qualitative composition of the identified changes is of interest. The results of a comparative analysis suggest that, in the model of forced swimming we developed, GTE promotes restoration of the body and moderate mobilization of the immune system, while small doses of ammonium salts, especially ammonium carbonate, contribute to an increase in physical performance, which is associated with satisfactory restoration of skeletal muscles and the entire body. The combined use of GTE with ammonium salts does not give a clearly positive effect.
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- 2024
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14. Experimental Test of the Acoustic Thermometry Method on a Long Track in the Sea of Japan
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Dolgikh, G. I., Morgunov, Yu. N., Bezotvetnykh, V. V., Burenin, A. V., Golov, A. A., Voitenko, E. A., Razhivin, V. V., and Tagiltsev, A. A.
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- 2023
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15. Creativity as a Basic Tool for Creating Innovative IT Products.
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Olena Verenych, Volodymyr Statsenko, Oleksandr Voitenko, Nadiya Fedoryatskaya, and Nataliia Lysenko
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- 2023
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16. Communications disruptor in project-oriented organisations.
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Vladyslav Kontsevyi and Oleksandr Voitenko
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- 2023
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17. Correlation of Bitumen Emulsion Stability Factor with Aqueous Phase Parameters Evaluated at the Stage of Composition Design
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Vysotskaya, M. A., Korotkov, A. V., Voitenko, O. N., Kukin, A. S., di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Klyuev, Sergey Vasil'yevich, editor, Klyuev, Alexander Vasil'yevich, editor, Vatin, Nikolay Ivanovich, editor, and Sabitov, Linar S., editor
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- 2023
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18. Mitochondrial malfunction mediates impaired cholinergic Ca2+ signalling and submandibular salivary gland dysfunction in diabetes
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Kopach, Olga, Pivneva, Tetyana, Fedirko, Nataliya, and Voitenko, Nana
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- 2024
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19. Influence of image forces on charge–dipole interaction in two-layered systems.
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Gabovich, Alexander M., Gorshkov, Vyacheslav N., Semeniuk, Valerii F., and Voitenko, Alexander I.
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ELECTRIC charge ,MAGNETIC dipoles ,INDUCED polarization ,DIPOLE interactions ,POLAR molecules ,EXCITON theory - Abstract
Interaction between a fixed point electric charge Q and a freely rotating point electric dipole with the magnitude P pinned near a plane interface between two dispersionless insulators with different dielectric permittivities ɛ
1 and ɛ2 has been considered. It was shown that, as a result of this interaction and the interaction of the dipole with the polarization charges induced at the interface by the charge Q and the dipole itself, there arise regions where the dipole can possess either one or two equilibrium orientations. The spatial distributions of the electrostatic dipole energy Wtotal under the combined action of the charge Q and the induced interface polarization charges, as well as the equilibrium dipole orientations (orientation maps), the boundaries between the regions with different numbers of dipole orientations, and their evolution with the variation of problem parameters (the charge and dipole magnitudes, the mismatch between ɛ1 and ɛ2 , and the charge–interface distance) were calculated. It was shown that there can emerge local minima of Wtotal , which may play the role of traps for dipoles (in particular, excitons in layered structures), and the corresponding requirements for the problem parameters were found. Most results were obtained in analytical form. The model can be applied to various physical systems, for instance, polar molecules, excitons, and trions in layered structures. [ABSTRACT FROM AUTHOR]- Published
- 2024
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20. Tectonophysical Forecasting Criteria of Vein Bodies Thicknesses in Deep Horizons of the Nadvigovaya Zone, Badran Ore Field, Republic of Sakha (Yakutia)
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Rebetsky, Yu. L. and Voitenko, V. N.
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- 2023
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21. Comprehensive Assessment of the Preparedness of Highly Qualified Field Hockey Players at the Stage of Direct Preparation for the Main Competitions
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Viktor Kostiukevych, Nataliia Lazarenko, Vadym Adamchuk, Natalia Shchepotina, Tetiana Vozniuk, Oksana Shynkaruk, Inna Asauliuk, Stanislav Konnov, and Serhii Voitenko
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highly qualified field hockey players ,stage of direct preparation for the main competitions ,comprehensive assessment of the preparedness ,ten-point scale ,Sports ,GV557-1198.995 - Abstract
The purpose of the study was to experimentally substantiate the methodological approach to the development of a comprehensive assessment of the preparedness of highly qualified field hockey players at the stage of direct preparation for the main competitions. Materials and methods. Highly qualified players, members of the national field hockey team of Ukraine (n=21) participated in the study. The average age of the players was (х ± S) 24.9 ± 5.76 years, their sports qualification was masters of sports of Ukraine. The study was conducted over the first and second competitive periods of the two-cycle planning of the training process of highly qualified field hockey players of the 2020-2021 sports season. During the first competitive period, a methodical approach to comprehensive assessment of the preparedness of highly qualified field hockey players was developed. Within the second competition period, which included the stage of direct preparation for the main competitions indicators of a comprehensive assessment of readiness of the players were determined. In order to develop a comprehensive assessment of fitness, tests and criteria were used to assess the level of physical, functional fitness, physical fitness in relation to technique and competitive activity of hockey players. Results. A methodical approach has been developed for the comprehensive assessment of the preparedness of highly qualified field hockey players according to the following algorithm: determination of criteria for the manifestation of physical and functional preparedness, physical preparedness in relation to technique, competitive activity; development of a 10-point rating scale; establishment of a comprehensive assessment of players’ readiness during the stage of direct preparation for the main competitions. Conclusions. The structure of the stage of direct preparation for the main competitions consisted of a basic and a special preparatory mesocycles. The volume of direct motor activity was 38 hours, in particular, the ratio of means: general preparatory exercises – 55.4%, special preparatory exercises – 19.5%, lead exercises – 10.9%, competitive exercises – 15.2%; ratio of training loads: aerobic – 56.5%, aerobic-anaerobic – 32.7%, anaerobic-lactate – 7.6%, anaerobic-glycolytic – 3.2%. A statistically probable positive change (р
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- 2023
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22. Structure and spectroscopy characterization of La$_{1-x}$Sm$_x$VO4 luminescent nanoparticles synthesized co-precipitation and sol-gel methods
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Chukova, O. V., Nedilko, S. A., Nedilko, S. G., Papadopoulos, A., Slepets, A. A., Stratakis, E. I., and Voitenko, T. A.
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Condensed Matter - Materials Science - Abstract
The Sm-activated orthvanadate nanoparticles were synthesized by co-precipitation and sol-gel methods. XRD study has shown that synthesized samples are characterized by monoclinic or tetragonal structure as well as their mixture dependently on Sm concentration and methods of synthesis. Influence of method of synthesis on morphology of nanoparticles, their absorption, diffuse reflectance and emission spectra was observed and studied.
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- 2020
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23. Pulsed laser deposition of the doped lanthanum vanadate nanoparticles on glass and silicon substrates
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Chukova, O., Nedilko, S. A., Nedilko, S. G., Voitenko, T., Androulidaki, M., Manousaki, A., Papadopoulos, A., Savva, K., and Stratakis, E.
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Physics - Applied Physics ,Condensed Matter - Materials Science - Abstract
Thin films from the lanthanum vanadate nanoparticles were successfully grown by pulsed laser deposition method on glass and silicon substrates for the first time. Morphology and thickness of the films depend on a type of substrate and a number of pulses. The films are of 27 to 220 nm thickness and formed by very small particles up to 20 nm and also can contain single nanoparticles with dimensions 40 to 60 nm and sometimes agglomerates of nanoparticles. Spectral properties of the samples have been investigated and discussed. The vanadate films deposited on the silicon substrates lead to appearance of antireflection properties in the visible range. Luminescence spectra of the investigated films consist of narrow lines caused by f-f transitions in the europium ions. For the samples on glass substrates the wide bands of glass emission are also contributed to the spectra. The optimal experimental conditions those allowed to obtain films promising for applications as luminescent converters are considered.
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- 2020
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24. Features of the Stress–Strain State of 3D Metal Objects Produced by Additive Microplasma Deposition of the Powder of a Fe–Cr–Ni–B–Si System
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Volodymyr Korzhyk, Shiyi Gao, Vladyslav Khaskin, Oleksandr Voitenko, Oksana Konoreva, Viktor Kvasnytskyi, and Andrii Perepichay
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microplasma deposition ,powder materials ,3D objects ,spatial primitives ,finite–element modeling ,residual deformations ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The objective of this study was the additive microplasma powder deposition of 3D metal products. The regularities of the influence of technological parameters of additive microplasma deposition of spatial objects using the powder filler material of a Fe–Cr–Ni–B–Si system on the formation of the microstructure and stress–strain state of 3D product material were studied in this work. Product walls with a layered metal structure with a deposited layer height of about 650 µm and 3.0–3.5 mm thickness were formed as a result of additive microplasma deposition of the HYF–103 powder of a Fe–Cr–Ni–B–Si system. The deposited metal ensured a high ultimate strength (above 600 MPa). The finite element method was used to derive the solution of the thermomechanical problem of additive deposition of 3D prototypes («cylinder», «triangular prism», «square prism», «reverse cone», «straight cone») with HYF–103 powder. The equivalent stresses of the highest magnitude (565 MPa) were predicted in the model sample of the “reverse cone” type, and the lowest stresses (552 MPa) were present in the sample of the “straight cone” type. For all the models, the maximal values of radial movements corresponded to the range of 0.22–0.28 mm. The respective technological mode of deposition was selected to minimize the stress–strain state of the produced 3D objects.
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- 2024
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25. Multiparticle fields on the subset of simultaneity
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Ptashynskiy, D. A., Zelentsova, T. M., Chudak, N. O., Merkotan, K. K., Potiienko, O. S., Voitenko, V. V., Berezovskiy, O. D., Opyatyuk, V. V., Zharova, O. V., Yushkevich, T. V., Sharph, I. V., and Rusov, V. D.
- Subjects
Physics - General Physics - Abstract
We propose a model describing the scattering of hadrons as bound states of their constituent quarks. We analyze the role of simultaneity in measurements of the characteristics of different particles for the description of relativistic quantum systems. We also consider the impossibility of the same realization of such measurements in different inertial reference frames because of the relativity of simultaneity in relativistic situation. On the basis of this analysis we conclude that the relativistic scattering of bound states of particles should not be described by the fields defined on the Minkowski space, but on the subset of simultaneous events, which is singled out from the tensor product of two Minkowski spaces. Such fields are called multi-particle fields. The arguments of the field functions in different reference frames are impossible to relate neither by using Lorentz transformations, nor in any other way. Next we build the dynamic equations for the multi-particle fields on the subset of simultaneity, using the Lagrange method, similar to the case of "usual" single-particle fields. We then consider the gauge fields restoring the local internal symmetry on the subset of simultaneity. The dynamic equations for the multi-particle gauge fields describe such phenomena as confinement and asymptotic freedom of colored objects under certain boundary conditions, and the mechanism of spontaneous braking of symmetry -- under anothers. With these dynamic equations we are able to describe within a single model the quark confinement in hadrons, and their interaction during hadron scattering through the exchange of the bound states of gluons -- the glueballs., Comment: 31 pages, 8 figures, in Ukrainian
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- 2019
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26. Political neutrality as an indicator of professional prosecution
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Anton Voitenko
- Subjects
policy ,neutrality ,political ignorance ,political literacy ,prosecutor ,professional skills ,professionalism ,Jurisprudence. Philosophy and theory of law ,K201-487 ,Public law ,K3150 ,Criminal law and procedure ,K5000-5582 ,Civil law ,K623-968 ,Private international law. Conflict of laws ,K7000-7720 ,Law of Europe ,KJ-KKZ ,Law of nations ,KZ2-6785 - Abstract
The relevance of the topic is determined by the importance of the principle of political neutrality as a preventive factor in the professional activity of the prosecutor, which calls for ensuring him from the external influence of any political force and the appearance of personal illegal interests in social cataclysms). The purpose of the article – to consider the professional activity of the prosecutor through the understanding of its principles as indicative characteristics of professional skills and professionalism. To confirm this, the author chose functionalism as the main methodological approach, which gave him reasons to claim that the functions of activity determine professional skills (the profession of a prosecutor), and the principles define professionalism (level of mastery of this profession). As auxiliary methods were used: formal-logical (for an argumentative presentation of the research material), formal-dogmatic (for the analysis of current regulatory documents) and comparative-legal (for comparison of the analyzed material). The main results of the study are shown the principle of political neutrality as a requirement in the field of professional activity of civil servants not only in Ukraine, but also in the European Union, the integration with which is defined as the main vector of further development of our state. A substantive distinction is made between political neutrality and synonymously similar concepts of political impartiality and independence, apoliticality and non-partisanship. At the same time, political neutrality is shown as one of the most important criteria in the formation of requirements for professional selection, professional training, professional development and professional activities of prosecutors. The practical value of the study is a warning to prosecutors against political ignorance, which can arise from a misunderstanding of political neutrality. In order to avoid or overcome this negative aspect, a number of factors are proposed for the prosecutor to achieve professional skills, which is described through a peculiar formula: the prosecutor's professional skills can be considered the sum of political, media and informational and environmental literacy, divided by political neutrality
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- 2023
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27. Production of Steel 26KHMFBA Continuously-Cast Billets for Casing Pipes Using Barium-Containing Master Alloy
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Rutskii, D. V., Morozov, V. V., Zyuban, N. A., Kirilichev, M. V., Nikititin, M. S., Voitenko, R. M., and Kharlamov, V. O.
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- 2022
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28. SECURITY POLICY IN THE BALTIC STATES AFTER THEIR RESTORATION OF INDEPENDENCE: ON THE EXAMPLE OF LATVIA
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Voitenko, Yu. M., primary
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- 2023
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29. Blind Vacant Frequency Channels Detection for Cognitive Radio.
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Inna Valieva, Bharath Shashidhar, Mats Björkman, Johan åkerberg, Mikael Ekström, and Iurii Voitenko
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- 2022
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30. Machine Learning-Based Frequency Bands Classification for Efficient Frequency Hopping Spread Spectrum Applications.
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Inna Valieva, Bharath Shashidhar, Mats Björkman, Johan åkerberg, Mikael Ekström, and Iurii Voitenko
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- 2022
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31. Hybrid Competencies Model for Managing Innovation Projects.
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Olena Verenych, Carsten Wolff, Sergiy Bushuyev, Olena Bondar, and Oleksandr Voitenko
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- 2022
32. The Principles of Forming a Data-Driven University Model Within the Cluster-Network Model of Innovative Development
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Gadasina, Lyudmila, Voitenko, Sergey, Vyunenko, Lyudmila, Spagnoletti, Paolo, Series Editor, De Marco, Marco, Series Editor, Pouloudi, Nancy, Series Editor, Te'eni, Dov, Series Editor, vom Brocke, Jan, Series Editor, Winter, Robert, Series Editor, Baskerville, Richard, Series Editor, Zaramenskikh, Evgeny, editor, and Fedorova, Alena, editor
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- 2022
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33. Influence of the Rear Verge Configuration of the Retaining Wall and Surface of Backfill on Active Pressure of Heterogeneous Anisotropic Soil
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Vynnykov, Yuriy, Voitenko, Inha, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Onyshchenko, Volodymyr, editor, Mammadova, Gulchohra, editor, Sivitska, Svitlana, editor, and Gasimov, Akif, editor
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- 2022
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34. Neuropathic pain changes the output of rat lamina I spino-parabrachial neurons
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Krotov, Volodymyr, Agashkov, Kirill, Romanenko, Sergii, Koroid, Kostiantyn, Krasniakova, Marharyta, Belan, Pavel, and Voitenko, Nana
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- 2023
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35. DETERMINATION OF THE INFLUENCE MECHANISMS OF SUCCINIC ACID-BASED DRUG ON IMPROVING THE STATE OF ERYTHROCYTE LINK OF OXYGEN TRANSPORT DURING AEROBIC PHYSICAL LOADS
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Larisa Gunina, Yurii Ataman, Ihor Belenichev, Roman Golovashchenko, Valentina Voitenko, and Victoria Bezugla
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aerobic loads, succinic acid, oxygen transport function of blood, erythrocyte membranes, lipid peroxidation ,Medicine (General) ,R5-920 - Abstract
Introduction. Strenuous aerobic work inherent to cyclical sports requires adequate oxygenation of the athletes’ working muscles. One of the ways to improve the oxygen transport function of blood is to optimize the structural and functional state of erythrocytes, for example, by using succinic acid in the form of the medical drug Armadin Long. This pharmacological drug is widespread in clinical practice for treating hypoxic and ischemic conditions, and very little is known about its use for improving the condition of the erythrocytes in the blood of athletes, which determined the relevance of this study. The objective of the study was to assess the feasibility and effectiveness of using the medical drug Armadine Long to improve the state of the erythrocyte link of the blood oxygen transport system during aerobic exercise. Materials and Methods. A randomized blinded placebo-controlled trial included 40 male middle-distance runners (aerobic discipline of athletics). The subjects were divided into two subgroups matched for number, age, and anthropometric characteristics (strats). In this work, laboratory methods were used, including hematological tests (in particular, hemoglobin and erythrocytes level measurement and erythrocyte characteristics evaluation), as well as biochemical method: the study of prooxidant and antioxidant balance (activity of lipid peroxidation according to changes in the content of maloniс dialdehyde and antioxidant protection according to changes in the concentration of reduced glutathione) and functional characteristics of erythrocyte membranes (permeability, sorption capacity, sorption capacity of the glycocalyx) as well as evaluation of the main components of lipid and protein composition of red blood cell membranes. Pedagogical research methods were based on the determination of relative aerobic capacity using the generally accepted PWC170 test. Results of the study. During 21 days of intensive loads, an almost two-fold increase in contents of malonic dialdehyde was observed with a parallel decrease in reduced glutathione content by 23.5 % during aerobic loads. At the same time, there was a deterioration of the functional characteristics of erythrocytes and a decrease in the relative aerobic capacity in comparison with the baseline data. The use of the medical drug Armadine Long at a dose of 600 mg per day improved the indicated characteristics of erythrocytes. At the same time, there were positive changes in the protein and lipid state of the erythrocyte membranes, and the athletes’ aerobic power increased by 38.7%. It substantiates the high ergogenic ability of succinic acid, which is based on the normalization of the lipoperoxidation process and the improvement of the structural and functional characteristics of erythrocyte membranes.
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- 2022
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36. Luminescence mechanisms in the 2V2O5–xLi2O–(98 − x)B2O3 glass matrices developed for creation of glass–ceramic materials
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Chukova, O., Nedilko, S. G., Voitenko, T., Minikayev, R., Paszkowicz, W., Stasiv, V., Zhydachevskyy, Y., and Suchocki, A.
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- 2023
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37. Quantification of 11 metabolites in rat urine after exposure to organophosphates
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Leninsky, Michael A., primary, Sobolev, Vladislav E., additional, Sokolova, Margarita O., additional, Voitenko, Natalya G., additional, and Skvortsov, Nikita V., additional
- Published
- 2024
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38. Immunological Profile and Markers of Endothelial Dysfunction in Elderly Patients with Cognitive Impairments
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Nikolay V. Goncharov, Polina I. Popova, Igor V. Kudryavtsev, Alexey S. Golovkin, Irina V. Savitskaya, Piotr P. Avdonin, Ekaterina A. Korf, Natalia G. Voitenko, Daria A. Belinskaia, Maria K. Serebryakova, Natalia V. Matveeva, Natalia O. Gerlakh, Natalia E. Anikievich, Marina A. Gubatenko, Irina A. Dobrylko, Andrey S. Trulioff, Arthur D. Aquino, Richard O. Jenkins, and Pavel V. Avdonin
- Subjects
aging ,immunosenescence ,endothelial cells ,acute ischemic stroke ,chronic cerebral circulation insufficiency ,diabetes mellitus ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. Further, damage to the endothelium can be both a cause and a consequence of many diseases, especially in elderly people. The purpose of this study was to carry out immunological and biochemical profiling of elderly people with acute ischemic stroke (AIS), chronic cerebral circulation insufficiency (CCCI), prediabetes or newly diagnosed type II diabetes mellitus (DM), and subcortical ischemic vascular dementia (SIVD). Socio-demographic, lifestyle, and cognitive data were obtained. Biochemical, hematological, and immunological analyses were carried out, and extracellular vesicles (EVs) with endothelial CD markers were assessed. The greatest number of significant deviations from conditionally healthy donors (HDs) of the same age were registered in the SIVD group, a total of 20, of which 12 were specific and six were non-specific but with maximal differences (as compared to the other three groups) from the HDs group. The non-specific deviations were for the MOCA (Montreal Cognitive Impairment Scale), the MMSE (Mini Mental State Examination) and life satisfaction self-assessment scores, a decrease of albumin levels, and ADAMTS13 (a Disintegrin and Metalloproteinase with a Thrombospondin Type 1 motif, member 13) activity, and an increase of the VWF (von Willebrand factor) level. Considering the significant changes in immunological parameters (mostly Th17-like cells) and endothelial CD markers (CD144 and CD34), vascular repair was impaired to the greatest extent in the DM group. The AIS patients showed 12 significant deviations from the HD controls, including three specific to this group. These were high NEFAs (non-esterified fatty acids) and CD31 and CD147 markers of EVs. The lowest number of deviations were registered in the CCCI group, nine in total. There were significant changes from the HD controls with no specifics to this group, and just one non-specific with a maximal difference from the control parameters, which was α1-AGP (alpha 1 acid glycoprotein, orosomucoid). Besides the DM patients, impairments of vascular repair were also registered in the CCCI and AIS patients, with a complete absence of such in patients with dementia (SIVD group). On the other hand, microvascular damage seemed to be maximal in the latter group, considering the biochemical indicators VWF and ADAMTS13. In the DM patients, a maximum immune response was registered, mainly with Th17-like cells. In the CCCI group, the reaction was not as pronounced compared to other groups of patients, which may indicate the initial stages and/or compensatory nature of organic changes (remodeling). At the same time, immunological and biochemical deviations in SIVD patients indicated a persistent remodeling in microvessels, chronic inflammation, and a significant decrease in the anabolic function of the liver and other tissues. The data obtained support two interrelated assumptions. Taking into account the primary biochemical factors that trigger the pathological processes associated with vascular pathology and related diseases, the first assumption is that purine degradation in skeletal muscle may be a major factor in the production of uric acid, followed by its production by non-muscle cells, the main of which are endothelial cells. Another assumption is that therapeutic factors that increase the levels of endothelial progenitor cells may have a therapeutic effect in reducing the risk of cerebrovascular disease and related neurodegenerative diseases.
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- 2024
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39. Erratum to: Experimental Test of the Acoustic Thermometry Method on a Long Track in the Sea of Japan
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Dolgikh, G. I., Morgunov, Yu. N., Bezotvetnykh, V. V., Burenin, A. V., Golov, A. A., Voitenko, E. A., Razhivin, V. V., and Tagiltsev, A. A.
- Published
- 2023
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40. Searching for New Biomarkers to Assess COVID-19 Patients: A Pilot Study
- Author
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Nikolay V. Goncharov, Piotr P. Avdonin, Natalia G. Voitenko, Polina A. Voronina, Polina I. Popova, Artemy V. Novozhilov, Maria S. Blinova, Victoria S. Popkova, Daria A. Belinskaia, and Pavel V. Avdonin
- Subjects
von Willebrand factor ,COVID-19 ,endothelial cells ,diagnostics ,biomarker ,albumin ,Microbiology ,QR1-502 - Abstract
During the initial diagnosis of urgent medical conditions, which include acute infectious diseases, it is important to assess the severity of the patient’s clinical state as quickly as possible. Unlike individual biochemical or physiological indicators, derived indices make it possible to better characterize a complex syndrome as a set of symptoms, and therefore quickly take a set of adequate measures. Recently, we reported on novel diagnostic indices containing butyrylcholinesterase (BChE) activity, which is decreased in COVID-19 patients. Also, in these patients, the secretion of von Willebrand factor (vWF) increases, which leads to thrombosis in the microvascular bed. The objective of this study was the determination of the concentration and activity of vWF in patients with COVID-19, and the search for new diagnostic indices. One of the main objectives was to compare the prognostic values of some individual and newly derived indices. Patients with COVID-19 were retrospectively divided into two groups: survivors (n = 77) and deceased (n = 24). According to clinical symptoms and computed tomography (CT) results, the course of disease was predominantly moderate in severity. The first blood sample (first point) was taken upon admission to the hospital, the second sample (second point)—within 4–6 days after admission. Along with the standard spectrum of biochemical indicators, BChE activity (BChEa or BChEb for acetylthiocholin or butyrylthiocholin, respectively), malondialdehyde (MDA), and vWF analysis (its antigen level, AGFW, and its activity, ActWF) were determined and new diagnostic indices were derived. The pooled sensitivity, specificity, and area under the receiver operating curve (AUC), as well as Likelihood ratio (LR) and Odds ratio (OR) were calculated. The level of vWF antigen in the deceased group was 1.5-fold higher than the level in the group of survivors. Indices that include vWF antigen levels are superior to indices using vWF activity. It was found that the index [Urea] × [AGWF] × 1000/(BChEb × [ALB]) had the best discriminatory power to predict COVID-19 mortality (AUC = 0.91 [0.83, 1.00], p < 0.0001; OR = 72.0 [7.5, 689], p = 0.0002). In addition, [Urea] × 1000/(BChEb × [ALB]) was a good predictor of mortality (AUC = 0.95 [0.89, 1.00], p < 0.0001; OR = 31.5 [3.4, 293], p = 0.0024). The index [Urea] × [AGWF] × 1000/(BChEb × [ALB]) was the best predictor of mortality associated with COVID-19 infection, followed by [Urea] × 1000/(BChEb × [ALB]). After validation in a subsequent cohort, these two indices could be recommended for diagnostic laboratories.
- Published
- 2023
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41. Non-resonant Alfv\'enic instability activated by high temperature of ion beams in compensated-current astrophysical plasmas
- Author
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Malovichko, Pavlo, Voitenko, Yuriy, and De Keyser, Johan
- Subjects
Physics - Space Physics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
Context: Compensated-current systems are established in response to hot ion beams in terrestrial foreshock regions, around supernova remnants, and in other space and astrophysical plasmas. Aims: We study a non-resonant reactive instability of Alfv\'en waves (AWs) propagating quasi-parallel to the background magnetic field $\mathbf{B}_{0}$ in such systems. Methods: The instability is investigated analytically in the framework of kinetic theory applied to the hydrogen plasmas penetrated by hot proton beams. Results: The instability arises at parallel wavenumbers $k_{z}$ that are sufficiently large to demagnetize the beam ions, $k_{z}V_{Tb}/\omega_{Bi}\gtrsim $ $1$ (here $V_{Tb}$ is the beam thermal speed along $\mathbf{B}_{0}$ and $\omega _{Bi}$ is the ion-cyclotron frequency). The Alfv\'en mode is then made unstable by the imbalance of perturbed currents carried by the magnetized background electrons and partially demagnetized beam ions. The destabilizing effects of the beam temperature and the temperature dependence of the instability threshold and growth rate are demonstrated for the first time. The beam temperature, density, and bulk speed are all destabilizing and can be combined in a single destabilizing factor $\alpha_{b}$ triggering the instability at {$\alpha _{b}>$ $\alpha _{b}^{\mathrm{thr}}$}, where the threshold varies in a narrow range $2.43\leq $ $\alpha _{b}^{\mathrm{thr}}\leq $ $4.87$. New analytical expressions for the instability growth rate and its boundary in the parameter space are obtained and can be directly compared with observations. Two applications to terrestrial foreshocks and foreshocks around supernova remnants are shortly discussed. In particular, our results suggest that the ions reflected by the shocks around supernova remnants can drive stronger instability than the cosmic rays.
- Published
- 2018
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42. THE ROLE OF PULMONARY REHABILITATION IN RECOVERY AFTER COVID-19
- Author
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Valentyna V. Voitenko, Valentyna P. Shevets, and Iryna A. Brizhata
- Subjects
covid-19, pulmonary rehabilitation, post-covid syndrome, telerehabilitation, physical therapy ,Medicine (General) ,R5-920 - Abstract
Introduction. The outbreak of coronavirus infection (COVID-19) continues to be one of the most serious problems of the mankind. Patients who develop pneumonia as a result of coronavirus infection require rehabilitation measures to restore the functional capacity of the body and to prevent the negative consequences of the disease. For patients with COVID‑19, rehabilitation should be aimed at alleviating symptoms (shortness of breath), improving psychological condition, physical form and quality of life. This can be achieved by improving the organization and methodology of pulmonary rehabilitation of patients with COVID-19. Purpose is to justify the use of pulmonary rehabilitation in patients with COVID-19. Materials and methods: analysis and systematization of data from modern scientific and methodological literature and Internet sources. Results. The emergence and spread of coronavirus (SARS-CoV-2) is a major public health issue. Post-COVID syndrome has already become a massive phenomenon and part of our lives. Recovery from coronavirus infection is necessary for all, regardless of the severity of the disease. Physical therapy can be used at various stages of treatment for COVID-19 patients. However, the decision to use it, the nature, scope and purpose of the interventions should be based on clinical evidence, the safety of patients and staff. Pulmonary rehabilitation, the main component of which is physical exercise (aerobic and/or resistance training), can play a vital role in the recovery of patients, improving physical fitness, muscle strength and quality of life of those infected with severe acute respiratory coronavirus syndrome. Moreover, under quarantine conditions, it was important for many patients to have access to home-based rehabilitation, which was provided by tele-rehabilitation facilities using telecommunications technology. Conclusions. Thus, pulmonary rehabilitation is an important part of recovery from COVID-19. The development of complications and the increase in the number of pulmonological patients who have suffered a severe or moderate coronary infection are updating the issues of adaptation of traditional rehabilitation programs to new conditions.
- Published
- 2022
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43. Comparative Performance of Soccer Teams of Different Age Groups
- Author
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Andriy Kolosov, Serhii Voitenko, Viktor Kostiukevych, Tetiana Vozniuk, Maksym Perepelytsia, Nataliia Svirshchuk, and Tamara Chernyshenko
- Subjects
soccer players ,efficiency ,interaction ,subjectivity ,organization ,Sports ,GV557-1198.995 - Abstract
The study purpose is to establish differences in the joint activities of soccer teams of different age. Materials and methods. Psychological methods for indicators of joint activity of sports teams were used. Statistical analysis was performed using non-parametric analysis of variance (Kruskal-Wallis H-test). The study involved 105 soccer players, including 37 boys aged 15–18, 45 juniors aged 19–21 and 23 adult athletes aged 22 and over. Results. In the young soccer players, group interaction, intellectual communication, psychological compatibility, as well as indicators of real and reflective group subjectivity are higher than in the adult and junior teams. The levels of group organization, diligence and success in performing sports tasks are dominant in the adult teams. At the same time, the integrative characteristic of joint sports activities is group efficiency, which is presumably the most pronounced in adults, thus characterizing the processes within the mental organization of joint activities of soccer players. It is the result of their cooperation, a transformed form of external teamwork. Conclusions. The organization of joint mental activity differs in different age groups. This affects the formation and development of intra-group position of the athletes, influencing their optimal involvement in the team in the performance of designed or creative functions. Keywords: soccer players, efficiency, interaction, subjectivity, organization.
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- 2022
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44. Morphogenesis, pigment content, phytohormones and yield of tomatoes under the action of gibberellin and tebuconazole
- Author
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V. V. Rogach, V. G. Kuryata, I. V. Kosakivska, L. V. Voitenko, M. M. Shcherbatyuk, and T. I. Rogach
- Subjects
lycopersicon esculentum ,growth stimulants and inhibitors ,morphometry ,leaf apparatus ,plant hormones ,crop capacity ,Science - Abstract
One of the main tasks of contemporary plant physiology is regulation of growth and development of cultivated plants in order to optimize the productive process. The scientific community focuses its attention on the use of natural activators and growth inhibitors. We investigated the effect of foliar treatment with 0.005% solution of gibberellic acid and 0.025% solution of the anti-gibberellic preparation tebuconazole on morphogenesis, leaf mesostructure, content of photosynthetic pigments, balance of endogenous phytobrybrides and lymphocyte B and productivity of tomatoes. The vegetation experiment was carried out in the conditions of soil-sand culture in vessels with a 10-liter volume. The treatment was carried out in the budding phase. Morphometric parameters were measured every 10 days. The mesostructure of the middle tier leaves was studied in the fruit formation phase, and the chlorophyll content was determined in the raw material by spectrophotometric method. Analytical determination of endogenous phytohormones – indolyl-3-acetic (IAA), gibberellic acid and abscisic (ABA) acids and cytokinins – zeatin (Z), zeatin-O-glucoside (ZG), zeatinribozide (Znila) and isopentenyladenosine (iPA) was performed by high performance liquid chromatography – mass spectrometry (HPLC-MS). With gibberellic acid treatment plant height increased significantly, while with tebuconazole it decreased. Gibberellic acid increased the number of leaves per plant, and tebuconazole did not change it. The preparations increased the number of leaf blades per leaf, the total number of leaf blades per plant, the weight of the raw material of leaves, the area of leaf blades and the area of the leaves at the end of the study period. The dry matter weight of stems and roots under the action of gibberellic acid increased, and during the treatment of tebuconazole decreased. Gibberellic acid increased the dry matter of the whole plant, and tebuconazole did not change it. Under the action of tebuconazole the content of chlorophyll in the leaves increased, while under the action of gibberellic acid it decreased. Both regulators increased the volume of columnar parenchyma cells. Gibberellic acid increased the size of spongy parenchyma cells, while tebuconazole did not change them. It is revealed that the action of exogenous gibberellic acid in stems and leaves increased the content of endogenous IAA and gibberellic acid, and tebuconazole decreased their content. The ABA content in stems and leaves increased with tebuconazole treatments and decreased with exogenous gibberellic acid. The total cytokinin content in the leaves was higher than in the stems in both the control and the experiment samples. Growth regulators induced an increase in the cytokinin pool in leaves and a decrease in stems. Gibberellic acid increased the content of all five forms of cytokinins in the leaves, and tebuconazole increased only two isoforms. In the stems under the action of both growth regulators the content of Z decreased and iP increased. The content of ZR and iPA in stems increased after the application of the retardant and decreased under the action of growth stimulant. The ZG content exceeded the control after gibberellic acid treatment and was in trace concentrations under the action of tebuconazole. Growth regulators optimized the productivity of tomato plants: under the action of gibberellic acid there was a considerable increase in the number of fruits per plant, and after the use of tebuconazole the average weight of one fruit significantly increased. The obtained results demonstrated that anatomical-morphological and structural-functional rearrangements in tomato plants under the action of exogenous gibberellic acid and tebuconazole occurred against the background of changes in the balance and distribution of endogenous hormones. Increased photosynthetic activity, stimulation of growth processes of some plant organs and inhibition of others increased the biological crop capacity.
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- 2022
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45. An Alternative Method for Solving Two Problems of the Standard Model
- Author
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Merkotan, K. K., Zelentsova, T. M., Chudak, N. O., Ptashynskyi, D. A., Urbanevich, V. V., Potiienko, O. S., Voitenko, V. V., Berezovskyi, O. D., Sharph, I. V., and Rusov, V. D.
- Subjects
Physics - General Physics - Abstract
Two problems of the Standard Model, associated with the introduction of non-gauge interactions and with the introduction of an electromagnetic field as a linear combination of fields on which various gauge groups are implemented, are analyzed. It is noticed that the existing model contains $U\left( 1 \right)-$ phase uncertainty of the matrix elements of the raising and lowering generators of the $SU\left( 2 \right)$ group. This uncertainty creates the condition for the additional local $U\left( 1 \right)-$ symmetry of the Standard Model Lagrangian with respect to the choice of various equivalent generator representations of the $SU\left( 2 \right)$ group, which is provided by the electromagnetic field. In this case, due to the different action of the raising and lowering generators on the fields of each generation of leptons and quarks, these fields interact with the electromagnetic field in different ways. It is also shown that considering the multi-particle gauge field a description of the Higgs mechanism can be obtained, free from the shortcomings of the well-known single-particle description, the main of which is the introduction of the non-gauge "phi-four" interaction, that is not reduced to the fundamental one. In the proposed model, the spontaneous symmetry breaking is achieved due to the same fundamental interaction, the mediating particle mass of which it provides., Comment: 34 pages, 1 figure
- Published
- 2017
46. Solar plasma radio emission in the presence of imbalanced turbulence of kinetic-scale Alfv\'en waves
- Author
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Lyubchyk, Olena, Kontar, Eduard, Voitenko, Yuriy, Bian, Nicolas, and Melrose, Donald
- Subjects
Physics - Space Physics ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics ,Physics - Plasma Physics - Abstract
We study the influence of kinetic-scale Alfv\'enic turbulence on the generation of plasma radio emission in the solar coronal regions where the plasma/magnetic pressure ratio $\beta $ is smaller than the electron/ion mass ratio $m_{e}/m_{i}$. The present study is motivated by the phenomenon of solar type I radio storms associated with the strong magnetic field of active regions. The measured brightness temperature of the type I storms can be up to $10^{10}$ K for continuum emission, and can exceed $10^{11}$ K for type I bursts. At present, there is no generally accepted theory explaining such high brightness temperatures and some other properties of the type I storms. We propose the model with the imbalanced turbulence of kinetic-scale Alfv\'en waves producing an asymmetric quasilinear plateau on the upward half of the electron velocity distribution. The Landau damping of resonant Langmuir waves is suppressed and their amplitudes grow spontaneously above the thermal level. The estimated saturation level of Langmuir waves is high enough to generate observed type I radio emission at the fundamental plasma frequency. Harmonic emission does not appear in our model because the backward-propagating Langmuir waves undergo a strong Landau damping. Our model predicts $100\%$ polarization in the sense of the ordinary (o-) mode of type I emission., Comment: 27 pages, 8 figures, accepted for publication in Solar Physics
- Published
- 2017
- Full Text
- View/download PDF
47. Investigation of Spectral Parameters of Constricted Arc Plasma for Welding Processes and Related Technologies.
- Author
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Chernyak, Valeriy, Korzhyk, Volodymyr, Gao, Shiyi, Khaskin, Vladyslav, Voitenko, Oleksandr, Illiashenko, Yevhenii, Xinxin Wang, Grynyuk, Andrii, Konoreva, Oksana, and Sviridova, Iryna
- Subjects
ELECTRIC welding ,WELDING defects ,PLASMA arcs ,LOCAL thermodynamic equilibrium ,ELECTRONIC excitation ,PLASMA arc welding - Abstract
The paper is devoted to investigation of spectral parameters of constricted arc plasma, as a foundation for further development of basic approaches to controlling of plasma-arc technologies of material treatment and welding. The relevance of application of spectrometric analysis of the welding arc consists in obtaining the possibility of sufficiently accurate control of its temperature and energy input into the product being welded, recording initiation of weld defects (internal pores), determination of atmospheric oxygen ingress into the weld pool, etc. The spectral composition, temperature and concentration of the constricted welding arc plasma were determined in the paper to more precisely define its physical characteristics at 80 and 100 A currents, in order to establish the further applicability of dynamic spectral analysis of a constricted plasma arc in control of welding processes. As modern spectrometers with CCD-detectors of the spectral range of 200 ÷ 1100 nm have the resolution of the order of 0.35 nm, which 2-3 times exceeds the quantization step by the measured wavelength, and may lead to considerable errors, an approach is proposed to increase the accuracy of spectrometric measurements to acceptable values. Radiation spectra of the constricted welding arc measured in the wavelength range of 650 ÷ 1000 nm allowed within the model of local thermodynamic equilibrium calculating the excitation temperature of the main spectral range components: Ar I and O I. It was established that the excitation temperature of electron levels of Ar atoms in the welding arc plasma only weakly depends on the discharge current, and it is equal to 13500 ± 500 K. Excitation temperature of O I electron levels was equal to 10000 ± 500 K at arc current of 100 A and to 7200 ± 500 K at 80 A current. Electron density of high-current welding arc plasma was measured by Stark broadening of Ar I lines (696.543; 772.4; 912.3 nm). It was found that with the rise of current of the constricted welding arc by 20%, an increase of charge concentration in the arc plasma by 1.5 times and of its temperature by 1.2 times are observed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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48. Testing Green Tea Extract and Ammonium Salts as Stimulants of Physical Performance in a Forced Swimming Rat Experimental Model.
- Author
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Korf, Ekaterina A., Novozhilov, Artem V., Mindukshev, Igor V., Glotov, Andrey S., Kudryavtsev, Igor V., Baidyuk, Ekaterina V., Dobrylko, Irina A., Voitenko, Natalia G., Voronina, Polina A., Habeeb, Samarmar, Ghanem, Afrah, Osinovskaya, Natalia S., Serebryakova, Maria K., Krivorotov, Denis V., Jenkins, Richard O., and Goncharov, Nikolay V.
- Subjects
LABORATORY rats ,SPORTS physiology ,PHYSICAL mobility ,TEA extracts ,SPORTS medicine ,SOLEUS muscle - Abstract
The study of drugs of natural origin that increase endurance and/or accelerate recovery is an integral part of sports medicine and physiology. In this paper, decaffeinated green tea extract (GTE) and two ammonium salts—chloride (ACL) and carbonate (ACR)—were tested individually and in combination with GTE as stimulants of physical performance in a forced swimming rat experimental model. The determined parameters can be divided into seven blocks: functional (swimming duration); biochemistry of blood plasma; biochemistry of erythrocytes; hematology; immunology; gene expression of slow- and fast-twitch muscles (m. soleus, SOL, and m. extensor digitorum longus, EDL, respectively); and morphometric indicators of slow- and fast-twitch muscles. Regarding the negative control (intact animals), the maximum number of changes in all blocks of indicators was recorded in the GTE + ACR group, whose animals showed the maximum functional result and minimum lactate values on the last day of the experiment. Next, in terms of the number of changes, were the groups ACR, ACL, GTE + ACL, GTE and NaCl (positive control). In general, the number of identified adaptive changes was proportional to the functional state of the animals of the corresponding groups, in terms of the duration of the swimming load in the last four days of the experiment. However, not only the total number but also the qualitative composition of the identified changes is of interest. The results of a comparative analysis suggest that, in the model of forced swimming we developed, GTE promotes restoration of the body and moderate mobilization of the immune system, while small doses of ammonium salts, especially ammonium carbonate, contribute to an increase in physical performance, which is associated with satisfactory restoration of skeletal muscles and the entire body. The combined use of GTE with ammonium salts does not give a clearly positive effect. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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49. 4K-model as a basis of improving project management maturity in the organization.
- Author
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Oleksandr Voitenko, Lyudmila Chernova, Liubava S. Chernova, and Alexander G. Timinsky
- Published
- 2021
- Full Text
- View/download PDF
50. Methodological Approach to the Implementation of the Biadaptive Development Program in the Organization on the Basis of Cognitive Improvement of Key Competencies.
- Author
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Alexander G. Timinsky, Oleksandr Voitenko, Lyudmila Chernova, and Liubava S. Chernova
- Published
- 2021
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