97 results on '"E. Bykov"'
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2. Frost heave estimation of marshy soil by ALOS PALSAR interferometry and geodetic leveling, case study from the Baikal Lake region.
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Tumen N. Chimitdorzhiev, Pavel N. Dagurov, Michael E. Bykov, Aleksey V. Dmitriev, and Irina Kirbizhekova
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- 2016
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3. On the 60th anniversary of Prof. Yuri N. Radayev
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Dmitriy E. Bykov, Maksim V. Nenashev, and Vladimir P. Radchenko
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Mechanics of Materials ,Applied Mathematics ,Modeling and Simulation ,Condensed Matter Physics ,Mathematical Physics ,Software ,Analysis - Abstract
February 10, 2022 the famous scientist in mechanics of solids and applied mathematics, teacher, organizer of science and higher education in Russia YuriN.Radayev is celebrating his60thanniversary. YuriN.Radayev is known as a prominent scientist in the field of mechanics and applied mathematics. The principal directions of his academic activity are the Mathematical Theory of Plasticity, Fracture Mechanics, the Theory of Cracks and Microdamages, Coupled Hyperbolic Thermoelasticity and Thermomechanics, Micropolar Elasticity, Mechanics of Granular Solids, Mechanics of Growing Solids. In this biographical background we discuss the scientific and educational work of Prof. Yuri N.Radayev, give an information on his achievements and a list of his main publications.
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- 2022
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4. Wastewater sediment treatment facilities in a large region as a multi-component system
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Konstantin L. Chertes, Olga V. Tupitsyna, Vitaliy N. Pystin, Nikolay I. Shestakov, Artem P. Seyanko, and Dmitry E. Bykov
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Introduction. The development of a sludge management technology requires the understanding of treatment facilities as complex multi-parameter systems having explicit correlations between the composition of wastewater and concentrated pollution. In this regard, the article discusses the establishment of environmentally friendly systems for the disposal of sewage sludge, taking into account the process features of treatment facilities. Materials and methods. The authors study the largest treatment facilities located in the Samara region, as well as various new and previously accumulated batches of sewage sludge in the area of their influence. The method of principal components is applied to solve the pre-set tasks. Results. Parametric criteria, used to evaluate the treatment facilities and the sludge they accumulate, are addressed in the article. The project also encompasses the calculation of environmental and resource parameters. Data centering and scaling were applied to the information obtained in the course of the project implementation, and the obtained data were further analyzed using the method of principal components. The results obtained with the help of the model, constructed using the method of principal components, are displayed in the graphs of accounts and loads, characterizing the relationship between the fields and parameters used to evaluate them. Conclusions. Following the analysis of 20 pre-selected sites of treatment facilities, 6 facilities were considered as rational, since they are characterized by the well-developed engineering infrastructure. The conditionally rational area includes 8 facilities. Sediment processing and disposal plants are to be established there upon completion of preliminary environmental surveys. The remaining 6 facilities are considered irrational, since their resource capacity is insufficient for efficient production processes. A systematic approach allows (1) arranging sewage sludge treatment facilities at wastewater treatment plants located in the rational and conditionally rational areas of development and (2) drafting process flow diagrams to ensure a higher involvement of sludge in reclamation processes.
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- 2022
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5. Eliciting the Truth.Dedicated to the 85th Anniversary of Professor Eduard Germanovich Bykov
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S. E. Bykov, L. N. Antakova, D. A. Atyakshin, and V. V. Shishkina
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Medal ,Clinical Practice ,Alma mater ,Honor ,Library science ,Russian federation ,Scientific activity - Abstract
Eduard Germanovich Bykov, a famous Russian morphologist, Doctor of Medical Sciences, Honored Scientist of the Russian Federation, Honorary Professor of N.N. Burdenko Voronezh State Medical Academy (VSMA), a founder and leader of Voronezh school of histochemistry would have been 85 years old on June 10, 2021. A key issue of his scientific activity was careful selection of sample preparation protocols for histochem ical analysis in order to increase objectivity of differential diagnosis ofbiopsy material in vivo in clinical practice and to solve urgent problems of pathomorphogenesis of the whole range of diseases. Novelty and perspectives of the conducted research allowed Eduard Germanovich to become a scientific supervisor and consultant of a large number of dissertationists who performed their research in alma mater and in universities of other cities of the USSR. From 1978 to 2008, Prof. Bykov was in charge of the Central Research Laboratory, N.N. Burdenko State Medical University, organizing work of laboratories as connecting elements between fundamental research and practical health care. Scientifically based methods of diagnosis, therapy and rehabilitation were developed an d implemented into practical healthcare in the Central ResearchInstitute. Eduard Germanovich created Voronezh Scientific School "Human Histochemistry. Clinical Histochemistry", which focused on preserving the vital chemical characteristics of the object of study. Prof. Bykov was repeatedly awarded with certificates of honor from the University Administration and the Government of Voronezh Region for achievements in research, teaching and social work. In April 2010 he was awarded by the Russian Federation of Cosmonautics with Academician M.V. Keldysh medal for a significant contribution to the development of Russian cosmonautics. In 2011 Professor Eduard Bykov was awarded the title of "Honorary Professor" of N.N. Burdenko Voronezh State Medical Academy.
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- 2021
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6. Chrome incorporation in high-pressure Fe–Mg oxides
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A. B. Woodland, K. Schumann, L. Uenver-Thiele, K. Rosbach, T. Boffa Ballaran, C. Melai, and E. Bykova
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Mineralogy ,QE351-399.2 - Abstract
The occurrence of Cr-bearing oxide phases as inclusions in diamonds and in extraterrestrial materials has the potential to serve as an indicator of formation conditions. However, such an application requires detailed knowledge of phase stabilities and the influence that Cr may have on its stability. To this end, the incorporation of Cr in high-pressure post-spinel Fe–Mg oxide phases was experimentally investigated at pressures of 14–22 GPa and temperatures between 1100 and 1600 °C using a multi-anvil press. We find that neither the Fe3Cr2O6 nor the Mg3Cr2O6 endmember composition is stable over the expected range of pressure and temperature where Fe5O6 itself is known to be stable. Further experiments along the Fe32+Fe23+O6–Fe32+Cr2O6 binary indicate only small amounts of Cr substitution are possible: ∼ 0.12 cations Cr per formula unit or ∼ 6 mol % Fe32+Cr2O6 component. In contrast, complete solid solution is apparent across both the Fe22+(Cr,Fe3+)2O5 and the Mg2(Cr,Fe3+)2O5 binaries, and there are indications of complete solution in the entire (Mg,Fe2+)2(Cr,Fe3+)2O5 quaternary system. The O5-structured phase usually coexists with (Fe,Mg)O. At 16–20 GPa, a post-spinel phase with O4 stoichiometry was occasionally encountered, having either a modified Ca-ferrite- (mCF-FeCr2O4) or a Ca-titanate-type (CT-MgCr2O4) structure. In one high-temperature experiment at 1600 °C, an unquenchable Mg-rich phase with a reconstructed Mg4Fe23+O7 stoichiometry occurred together with Mg2(Cr,Fe3+)2O5. In one experiment at 1100 °C and 16 GPa with a bulk composition of Mg2(Cr0.6,Fe0.43+)2O5, an assemblage of O5 phase + eskolaite–hematite solid solution + periclase was obtained together with minor amounts of the CT-type phase and a β-(Cr,Fe)OOH phase. The occurrence of these two minor phases in this low-temperature experiment is an indicator of variable reaction kinetics amongst the starting materials, which caused chemical heterogeneities to develop at the onset of the experiment. The structural systematics of Fe22+(Cr,Fe3+)2O5 and (Fe2+,Mg)2(Cr,Fe3+)2O5 solid solutions were investigated. It is notable that the Fe3+ and Cr endmembers have somewhat different crystal structures, belonging to space groups Cmcm (no. 63) and Pbam (no. 55), respectively. The phase transition occurs around the midpoint of the Fe3+–Cr joins. In spite of complexities in the behavior of the unit-cell parameters, the variation in molar volume with composition deviates only slightly from linearity. Wüstite and periclase coexisting in our experiments reveal the incorporation of up to 9 wt % and 25 wt % Cr2O3, respectively. This is consistent with the minor Cr contents reported for some ferropericlase inclusions in natural diamond. The limited solubility of other cations in Fe5O6 limits the likelihood of it being an accessory phase in the Earth's deep upper mantle and transition zone, except in Fe-rich environments. In contrast, the O5 phase appears to be more flexible in accommodating a range of divalent and trivalent cations, suggesting that this phase is more likely to be stabilized, potentially where redox reactions related to diamond formation occur.
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- 2024
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7. On the high-field characterization of magnetocaloric materials using pulsed magnetic fields
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C Salazar Mejía, T Niehoff, M Straßheim, E Bykov, Y Skourski, J Wosnitza, and T Gottschall
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General Energy ,Materials Science (miscellaneous) ,Materials Chemistry - Abstract
Magnetic refrigeration is a highly active field of research. The recent studies in materials and methods for hydrogen liquefaction and innovative techniques based on multicaloric materials have significantly expanded the scope of the field. For this reason, the proper characterization of materials is now more crucial than ever. This makes it necessary to determine the magnetocaloric and other physical properties under various stimuli such as magnetic fields and mechanical loads. In this work, we present an overview of the characterization techniques established at the Dresden High Magnetic Field Laboratory in recent years, which specializes in using pulsed magnetic fields. The short duration of magnetic-field pulses, lasting only some ten milliseconds, simplifies the process of ensuring adiabatic conditions for the determination of temperature changes, Δ T a d . The possibility to measure in the temperature range from 10 to 400 K allows us to study magnetocaloric materials for both room-temperature applications and gas liquefaction. With magnetic-field strengths of up to 50 T, almost every first-order material can be transformed completely. The high field-change rates allow us to observe dynamic effects of phase transitions driven by nucleation and growth as well. We discuss the experimental challenges and advantages of the investigation method using pulsed magnetic fields. We summarize examples for some of the most important material classes including Gd, Laves phases, La–Fe–Si, Mn–Fe–P–Si, Heusler alloys and Fe–Rh. Further, we present the recent developments in simultaneous measurements of temperature change, strain, and magnetization, and introduce a technique to characterize multicaloric materials under applied magnetic field and uniaxial load. We conclude by demonstrating how the use of pulsed fields opens the door to new magnetic-refrigeration principles based on multicalorics and the ‘exploiting-hysteresis’ approach.
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- 2023
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8. Earth Surface Subsidence in the Kuznetsk Coal Basin Caused by Manmade and Natural Seismic Activity According to ALOS PALSAR Interferometry.
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Alexander I. Zakharov, Michael I. Epov, Valery L. Mironov, Tumen N. Chymitdorzhiev, Victor S. Seleznev, Alexander F. Emanov, Michael E. Bykov, and Vladimir A. Cherepenin
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- 2013
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9. ASSOCIATIVE DETERMINANTS OF THE TROPHOLOGICAL STATUS IN ATHLETES FROM AEROBIC AND ANAEROBIC SPORTS
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A Kuzin, A Khrebtova, O Camerer, and E Bykov
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biology ,Anthropometric data ,Athletes ,business.industry ,Physiology ,Physical Therapy, Sports Therapy and Rehabilitation ,biology.organism_classification ,Physical performance ,Total cholesterol ,Aerobic exercise ,Medicine ,Orthopedics and Sports Medicine ,Glucose dynamics ,business ,Anaerobic exercise ,Morning - Abstract
Aim. The paper aims to elaborate effectiveness criteria for aerobic and anaerobic training based on a comprehensive analysis of the athletes’ trophological status. Materials and methods. Anthropometric data, body composition, carbohydrate and fat metabolism indicators were collected for trained athletes (n = 41) once per day (in the morning) on an empty stomach. To find metabolic determinants for the training process of various orientations, athletes were divided into two groups, namely, a group with a predominantly aerobic orientation (n = 23) and those with a predominantly anaerobic one (n = 18). Results. The assessment of the athletes’ trophological status showed reliable correlations between body composition and aerobic capacities. Body composition indicators allow forecasting physical performance in predominantly aerobic sports. Total cholesterol and blood glucose dynamics reflect the nature of metabolic changes during long-term adaptation to aerobic and anaerobic exercises. Conclusion. In the group with aerobic training, sportsmanship depends on the anthropological and trophological statuses. The ratio of blood glucose to total cholesterol can act as a universal marker of aerobic and anaerobic capacities during long-term sports training.
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- 2020
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10. Magnetocaloric effectin polycrystalline DyAl2
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Sergey Taskaev, M. Ulyanov, E. Bykov, T. Gottschall, Wei Liu, M. Bogush, D. Bataev, M. Kononova, M. Gavrilova, Vladimir Khovaylo, Konstantin P. Skokov, Z. Hu, A. Basharova, and D. Plakhotskiy
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Materials science ,Ferromagnetism ,Condensed matter physics ,General Mathematics ,Magnetic refrigeration ,General Physics and Astronomy ,Crystallite ,Laves phase - Published
- 2020
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11. THE FEATURES OF MYOCARDIAL HEMODYNAMIC AND VEGETATIVE HOMEOSTASIS IN ATHLETES OF DIFFERENT QUALIFICATIONS FROM ACYCLIC SPORTS
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E Bykov, A Chipyshev, O Balberova, and E Sabiryanova
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medicine.medical_specialty ,biology ,Athletes ,business.industry ,Internal medicine ,medicine ,Cardiology ,Hemodynamics ,Physical Therapy, Sports Therapy and Rehabilitation ,Orthopedics and Sports Medicine ,biology.organism_classification ,business ,Homeostasis - Abstract
Aim. The article deals with studying the functional status of the cardiovascular system and the features of its regulation in athletes of different qualifications from acyclic sports. Materials and methods. Male athletes of different qualifications aged 18–22 years and involved in acyclic sports participated in the study. A complex noninvasive bioimpedance study of HRV and hemodynamics was conducted with the Centaur (Microlux) system. The study of morphofunctional indicators of the myocardium was performed with echocardiography. Results. In athletes with the rank of Master of Sports adaptation to physical training is implemented through the increase in stroke volume, end-diastolic volume, end-systolic volume, the humoral metabolic activity of heart rate regulation, and myocardial thickening. In the athletes of the 1st and 2nd ranks, there is a predominance of sympathetic activity in heart rate regulation and the chronotropic mechanism in response to physical load, which proves their less perfect adaptation. Conclusion. Based on the results obtained in the transition period of training the features of myocardial hemodynamic and vegetative homeostasis were revealed. Namely, the increase in qualifications and sports performance enhancement are determined by both morphofunctional changes in the heart, and the improvement of heart rate regulation mechanisms and cardiac contractile function.
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- 2019
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12. Surgical treatment for the single ventricle with subaortic obstruction. Clinical case of the Damus-Kaye-Stansel procedure
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S. E. Bykov, S. A. Kovalev, D. Yu. Gryaznov, E. I. Korosan, and W. M. Novick
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medicine.medical_specialty ,congenital, hereditary, and neonatal diseases and abnormalities ,business.industry ,Hemodynamics ,damus-kaye-stansel procedure ,General Medicine ,030204 cardiovascular system & hematology ,Shunt (medical) ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,single ventricle ,030228 respiratory system ,Ventricle ,Internal medicine ,subaortic obstruction ,Cardiology ,Medicine ,business - Abstract
We present a case of hemodynamic correction for the single ventricle combined with subaortic obstruction and coarctation in an infant. The Damus-Kaye-Stansel procedure with modified double-barrel technique was performed. The pulmonary flow was provided with modified Blalock-Taussig shunt. The early postoperative period was characterized by multiple organ failure. Subsequently, the infant underwent the next stages of hemodynamic correction with good long-term results.
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- 2019
13. Remediation of Mineral Resources Polluted by Oil Refineries
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D. E Bykov, K.L. Chertes, A.A. Pod’yachev, V.N. Pystin, E.N. Petrenko, and O.V. Tupitsyna
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Pollutant ,Ecology ,Waste management ,Environmental remediation ,Lens (hydrology) ,Oil refinery ,0211 other engineering and technologies ,02 engineering and technology ,Management, Monitoring, Policy and Law ,Contamination ,Pollution ,Mineral resource classification ,Natural (archaeology) ,020401 chemical engineering ,021105 building & construction ,Environmental science ,Extraction (military) ,0204 chemical engineering - Abstract
The features of the genesis of technogenic lens elements of hydrocarbons under the sites of oil refineries are considered. Recommendations are given for the study and assessment of the dynamics of the state and migration of accumulated hydrocarbons in the geological environment using numerical and 3D modeling. The differences of technogenic lens elements from oil fields of natural origin are presented. It is shown that the object under study adversely affects all components of the geological environment. To reduce the anthropogenic load exerted by the oil lens elements, a physicochemical method has been proposed for cleaning contaminated rocks from pollutants using surfactants. This technology allows for the rehabilitation of the geological environment and at the same time to intensify the extraction of commercial hydrocarbons accumulated under the territories of oil refineries.
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- 2019
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14. Water-Soluble Heliomycin Derivatives to Target i-Motif DNA
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Georgy Y Nadysev, George V. Zatonsky, Eugene E Bykov, Pin Ju Chueh, Zoë A. E. Waller, Alexander S. Tikhomirov, Andrey E. Shchekotikhin, and Mahmoud A. S. Abdelhamid
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Scaffold ,Pharmaceutical Science ,01 natural sciences ,DNA sequencing ,Analytical Chemistry ,Cell Line ,chemistry.chemical_compound ,Mice ,Derivative (finance) ,Drug Discovery ,Side chain ,Animals ,Humans ,Polycyclic Compounds ,Pharmacology ,Natural product ,010405 organic chemistry ,Organic Chemistry ,Water ,DNA ,Combinatorial chemistry ,0104 chemical sciences ,G-Quadruplexes ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,chemistry ,Solubility ,Duplex (building) ,Molecular Medicine ,Nucleic Acid Conformation ,Selectivity - Abstract
Heliomycin (also known as resistomycin) is an antibiotic with a broad spectrum of biological activities. However, low aqueous solubility and poor knowledge of its chemical properties have limited the development of this natural product. Here, we present an original scheme for the introduction of aminoalkylamine residues at positions 3, 5, and 7 of heliomycin and, using this, have prepared a series of novel water-soluble derivatives. The addition of side chains to the heliomycin scaffold significantly improves their interaction with different DNA secondary structures. One derivative, 7-deoxy-7-(2-aminoethyl)amino-10-O-methylheliomycin (8e), demonstrated affinity, stabilization potential, and good selectivity toward i-motif-forming DNA sequences over the duplex and G-quadruplex. Heliomycin derivatives therefore represent promising molecular scaffolds for further development as DNA-i-motif interacting ligands and potential chemotherapeutic agents.
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- 2021
15. Magnetocaloric effect in the Laves-phase Ho1−xDyxAl2 family in high magnetic fields
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E. Bykov, W. Liu, K. Skokov, F. Scheibel, O. Gutfleisch, S. Taskaev, V. Khovaylo, D. Plakhotskiy, C. Salazar Mejia, J. Wosnitza, T. Gottschall
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- 2021
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16. Quantum chemical study of the reactivity of 3-brommaleimide and 3-(arylamino)maleimide derivatives
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Alexey A. Panov, Eugeny E. Bykov, Alexey S Trenin, S. N. Lavrenov, Alexander Y. Simonov, and Alexander M. Korolev
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Quantum chemical ,Steric effects ,Electron density ,Partial charge ,chemistry.chemical_compound ,Molecular model ,Chemistry ,Computational chemistry ,chemistry.chemical_element ,Reactivity (chemistry) ,Carbon ,Maleimide - Abstract
The difference in the reactivity of maleimide derivatives is explained by the method of calculating partial charges on carbon atoms of 3-substituted-4-bromomaleimides, as well as by 3D molecular modeling. The influence of various substituents on the electron density is studied, and the significant role of steric factors is shown. In the case of 3- (arylthio)- 4-bromomaleimides the most favorable structure is devoid of steric obstacles, which may explain the high reactivity of this compound.
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- 2021
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17. Correction to: GIMLi: Global Ionospheric total electron content model based on machine learning
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Aleksei Zhukov, Yury Yasyukevich, and Aleksei E. Bykov
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Computer science ,Ionospheric total electron content ,business.industry ,General Earth and Planetary Sciences ,Aerospace engineering ,business - Abstract
In the original article published, the references Wang et al. 2016a and Wang et al. 2016b are incorrect.
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- 2020
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18. GIMLi: Global Ionospheric total electron content model based on machine learning
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Yury Yasyukevich, Aleksei E. Bykov, and Aleksei Zhukov
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010504 meteorology & atmospheric sciences ,Total electron content ,Artificial neural network ,business.industry ,Anomaly (natural sciences) ,Linear model ,010502 geochemistry & geophysics ,Machine learning ,computer.software_genre ,01 natural sciences ,Standard deviation ,Data set ,General Earth and Planetary Sciences ,Artificial intelligence ,Gradient boosting ,business ,computer ,0105 earth and related environmental sciences ,Test data ,Mathematics - Abstract
EXtreme Gradient Boosting over Decision Trees (XGBoost or XGBDT) is a powerful tool to model a wide range of processes. We propose a new approach to create a global total electron content model, using machine-learning-based techniques, in particular, gradient boosting. The model is based on the Global Ionospheric Maps computed by Universitat Politecnica de Catalunya with a tomographic-kriging combined technique (UQRG). To reduce the problem complexity, we used empirical orthogonal functions (EOFs). The created model involves the first 16 spatial EOFs. For training and validation we used the 1998–2016 data sets, and the 2017 data as a test data set. To drive the model, we used the following features: (1) geomagnetic activity indexes (Kp, Ap, AE, AU, AL) and solar activity indexes (R, F10.7); (2) derivative values from these indexes such as the mean value and standard deviations within the last 12 h, last 11 days, and last 40 days; (3) day of the year (DOY); (4) averaged EOFs for given Kp and UT, and those for a given DOY and UT. The validation data set revealed the following hyperparameters for XGBoost learning: number of trees is 100, tree depth is 6, and learning rate is 0.1. Comparisons with the NeQuick2, Klobuchar, and GEMTEC models show that machine learning achieves higher accuracy for the 2017 test data set. The global averaged root-mean-square errors and mean absolute percentage errors were about 2.5 TECU and 19% for the nonlinear GIMLi-XGBDT model, about 4 TECU and 30–40% for NeQuick2, GEMTEC, and the linear model GIMLi-LM, and about 5.2 TECU and 73% for the Klobuchar model. A 4-fully-connected-layer artificial neural network provided a higher error (3.28 TECU and 27.7%) as compared to GIMLi-XGBDT. For all models mentioned, the error peaked in the equatorial anomaly region. The solar activity increase does not affect the error of the nonlinear GIMLi-XGBDT model. However, an increase in geomagnetic activity strongly affects that model.
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- 2020
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19. Discovery of Amphamide, a Drug Candidate for the Second Generation of Polyene Antibiotics
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Anna N. Tevyashova, George V. Zatonsky, Evgeny E. Bykov, Svetlana E. Solovieva, Olga S. Ostroumova, Treshchalin Ivan D, Andrey E. Shchekotikhin, E. R. Pereverzeva, Elena B. Isakova, Natalia E. Grammatikova, Elena P. Mirchink, Svetlana S. Efimova, and E. N. Bychkova
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0301 basic medicine ,Drug ,Antifungal Agents ,medicine.drug_class ,media_common.quotation_subject ,030106 microbiology ,Antibiotics ,Polyenes ,Pharmacology ,Nephrotoxicity ,Sepsis ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,Amphotericin B ,medicine ,Animals ,Prospective Studies ,media_common ,Chemistry ,Polyene ,medicine.disease ,Acute toxicity ,Anti-Bacterial Agents ,030104 developmental biology ,Infectious Diseases ,Pharmaceutical Preparations ,Toxicity ,medicine.drug - Abstract
Amphotericin B (AmB, 1) is the drug of choice for treating the most serious systemic fungal or protozoan infections. Nevertheless, its application is limited by low solubility in aqueous media and serious side effects such as infusion-related reactions, hemolytic toxicity, and nephrotoxicity. Owing to these limitations, it is essential to search for the polyene derivatives with better chemotherapeutic properties. With the objective of obtaining AmB derivatives with lower self-aggregation and improved solubility, we synthesized a series of amides of AmB bearing an additional basic group in the introduced residue. The screening of antifungal activity in vitro revealed that N-(2-aminoethyl)amide of AmB (amphamide, 6) had superior antifungal activity compared to that of the paternal AmB. Preclinical studies in mice confirmed that compound 6 had a much lower acute toxicity and higher antifungal efficacy in the model of mice candidosis sepsis compared with that of AmB (1). Thus, the discovered amphamide is a promising drug candidate for the second generation of polyene antibiotics and is also prospective for in-depth preclinical and clinical evaluation.
- Published
- 2020
20. Measurement of Grain Boundary Properties in Cu(ln,Ga)Se2 Thin Films
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A. Wall, C. Reinhardt, Steven J. Rozeveld, and E. Bykov
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010302 applied physics ,Materials science ,Recrystallization (geology) ,General Computer Science ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Copper indium gallium selenide solar cells ,Grain size ,0103 physical sciences ,Grain boundary ,Texture (crystalline) ,Crystallite ,Composite material ,Thin film ,0210 nano-technology ,Electron backscatter diffraction - Abstract
Semiconductors CulnSe2 (CIS) and alloys of Cu(ln,Ga)Se2 (CIGS) are often used as the light absorbing layer in thin film photovoltaic devices. These polycrystalline materials reach good conversion efficiencies despite the presence of grain boundaries, which can degrade device performance. Grain properties such as size distribution and orientation can be characterized using electron backscatter diffraction (EBSD). The EBSD method has been used extensively to determine texture and recrystallization in metal forming processes but to a lesser extent for characterization of CIGS thin film properties. This article describes measurements of grain properties for CIGS thin films grown under different reaction conditions.
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- 2018
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21. Development of scientific grounds of the enterprises waste management of chemical and petrochemical industry
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O.V. Tupicyna, K.L. Chertes, V.N. Pystin, N.G. Gladyshev, A.Yu. Churkina, and D. E. Bykov
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Petrochemical ,Waste management ,Business - Published
- 2018
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22. DEVELOPMENT OF PRODUCTS WITH ANTIOXIDANT PROPERTIES ON THE BASIS OF BERRY RAW MATERIAL
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Anastasiia O. Ustinovich, Aleksey E. Bykov, Irina V. Kalinina, and Evgeniia V. Ponyatenko
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Antioxidant ,Chemistry ,medicine.medical_treatment ,medicine ,General Medicine ,Food science ,Berry ,Raw material - Published
- 2018
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23. REQUIREMENTS FOR DRILLING CUTTINGS AND EARTH-BASED BUILDING MATERIALS
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V.N. Pystin, K.L. Chertes, G. G. Gilaev, E. G. Martynenko, Olga Vladimirovna Tupicyna, and D. E. Bykov
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Petroleum engineering ,utilization of drilling cuttings ,slurry-cement mixture ,Drilling ,lcsh:HD9715-9717.5 ,Cutting ,lcsh:Construction industry ,restoration of lands ,technogenic raw materials ,Earth (chemistry) ,neutralization of drilling cuttings ,lcsh:Architecture ,Geology ,lcsh:NA1-9428 - Abstract
In this article, the problem of utilization of drilling cuttings by means of scavenging, is researched. The product received could be used for the restoration of lands disturbed during construction and economic activities. When assessing technogenic formations, the binary approach was used, as a system of two components. The purpose of the study is to assess the state and possibility of utilizing drilling cuttings as raw materials in order to produce technogenic building materials; to study the effect of the degree of homogeneity of initial mixtures based on drilling cuttings, on kinetics of their hardening which leads to obtaining final products for various applications . As a result of research, relations of hardening and subsequent strengthening of slurry-cement mixtures were obtained; the plan of the process area for treatment of drilling cuttings is presented on the spot of demolished drilling pit.
- Published
- 2017
24. Verification of oligomycin A structure: synthesis and biological evaluation of 33-dehydrooligomycin A
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Olga A. Omelchuk, Olga B. Bekker, Eugene E Bykov, Lyubov G. Dezhenkova, Vladimir B. Tsvetkov, Andrey E. Shchekotikhin, Alexander M. Korolev, Valery N. Danilenko, Natalya E Grammatikova, Oleg Y Saveljev, and Lyudmila N. Lysenkova
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0301 basic medicine ,Antifungal Agents ,Magnetic Resonance Spectroscopy ,Oligomycin ,Stereochemistry ,Antineoplastic Agents ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Cell Line, Tumor ,Drug Discovery ,Humans ,Candida ,Pharmacology ,ATP synthase ,biology ,010405 organic chemistry ,Dimethyl sulfoxide ,fungi ,Kornblum oxidation ,Nuclear magnetic resonance spectroscopy ,Streptomyces fradiae ,biology.organism_classification ,Tautomer ,Streptomyces ,Anti-Bacterial Agents ,0104 chemical sciences ,030104 developmental biology ,chemistry ,Docking (molecular) ,biology.protein ,Oligomycins - Abstract
Although, the structure of oligomycin A (1) was confirmed by spectroscopic and chemical evaluations, some crystallographic data cast doubt on the originally adopted structure of the side 2-hydroxypropyl moiety of this antibiotic. It was suggested that the side chain of the oligomycin is enol-related (2-hydroxy-1-propenyl). To clarify this matter we synthesized and evaluated 33-dehydrooligomycin A (2) prepared by the Kornblum oxidation of 33-O-mesyloligomycin A (3) by dimethyl sulfoxide. NMR data for 33-dehydrooligomycin (2) and results of quantum chemical calculations have shown that this derivative exists in the keto rather than in the enol tautomer 2a. The in vitro antimicrobial activity of 2 was approximately two times weaker in comparison with oligomycin A against Streptomyces fradiae ATCC-19609 and reference Candida spp. strains and similar activity against certain filamentous fungi. The docking binding estimate of 2 with FOF1ATP synthase showed a slight decrease in binding affinity for 2 when compared with oligomycin A; that correlated with its activity against S. fradiae ATCC 19609 that is supersensitive to oligomycin A. The in vitro antiproliferative activities of 2 are also discussed.
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- 2017
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25. Samara Polytech Innovation: Digital Campus 2.0
- Author
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Anton Ivaschenko, Oleg Surnin, Pavel Sitnikov, Evgeny Frank, Oleg Golovnin, and Dmitry E. Bykov
- Subjects
business.industry ,Computer science ,010401 analytical chemistry ,05 social sciences ,Control (management) ,050301 education ,Information technology ,Space (commercial competition) ,Samara ,Digital library ,01 natural sciences ,0104 chemical sciences ,Identification (information) ,Engineering management ,Technical university ,State (computer science) ,business ,0503 education - Abstract
The paper considers an innovative solution of University infrastructure digitalization based on the implementation of an original stack of information technologies. The proposed solution includes students, teachers, and university employees' identification, adaptive acquiring in multiple sales points, digital library and smartphones mobile application. Student identification is connected with banking card that improves an opportunity of the interaction in virtual educational space. Some services are provided for parents to monitor and control the students' financial operations and academic progress. Special intelligent module is introduced for coordination and decision-making support. Research conclusions and recommendations are illustrated by the implementation results in Samara State Technical University.
- Published
- 2019
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- View/download PDF
26. Monitoring of the hydrological regime of the Saratov reservoir using the MNDWI index
- Author
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D. N. Sherstobitov, A. A. Bochkina, V. V. Ermakov, O. V. Tupitsyna, K. L. Chertes, and D. E Bykov
- Subjects
Hydrology ,Index (economics) ,Environmental science - Abstract
The article analyzes the possibilities of using Earth remote sensing (ERS) indices for monitoring the state of the environment. The possibility of using remote sensing indices for monitoring and forecasting the state of water bodies and watercourses, their hydrological characteristics was assessed. Within Samara region, the possibility of using the Modified Normalized Difference Water Index (MNDWI) to assess the water saturation of the Saratov reservoir in the Vasilievsky Islands area was considered. This territory was chosen due to the fact that it is sufficiently indicative for assessing changes in the hydrological regime of the reservoir. The processing of multispectral images taken by the Sentinel-2 satellite was carried out on the basis of green and short-wavelength spectral channels. The area of the water surface was calculated based on the number of binary pixels of the processed images. In accordance with the calculations, it was revealed that the area of the Saratov reservoir in the Vasilievsky Islands area has increased. At the same time, it was noted that the area of the water surface of small water bodies that have no connection with the reservoir has increased. The results obtained showed a high efficiency of monitoring changes in the hydrological regime of the reservoir when using the MNDWI.
- Published
- 2021
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27. Heterocyclic analogs of 5,12-naphtacenequinone 13*. Synthesis of 4,11-diaminoanthra[2,3-b]furan-5,10-diones and sulfur-containing analogs
- Author
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Alexander M. Korolev, Andrey E. Shchekotikhin, Yury N. Luzikov, Eugeny E. Bykov, and Alexander S. Tikhomirov
- Subjects
chemistry.chemical_compound ,010405 organic chemistry ,Chemistry ,Tetrabutylammonium hydroxide ,Furan ,Organic Chemistry ,Amino derivatives ,Organic chemistry ,Alkylation ,010402 general chemistry ,Sulfur containing ,01 natural sciences ,0104 chemical sciences - Abstract
We have developed an effective method for the synthesis of 4,11-diaminoanthra[2,3-b]furan-5,10-dione and 4,11-diaminoanthra[2,3-b]-thiophene-5,10-dione derivatives based on the substitution of 4,11-alkoxy groups with n-butylamine and subsequent oxidative dealkylation of n-butylamino groups via treatment with tetrabutylammonium hydroxide in DMSO.
- Published
- 2016
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28. Quantitative parameters of complexes of tris(1-alkylindol-3-yl)methylium salts with serum albumin: Relevance for the design of drug candidates
- Author
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Vladimir B. Tsvetkov, Dmitry N. Kaluzhny, Sergey N. Lavrenov, Anna N. Tevyashova, Nikita A. Durandin, Maria N. Preobrazhenskaya, and Evgeny E. Bykov
- Subjects
Tris ,Steric effects ,Indoles ,Stereochemistry ,Biophysics ,Serum albumin ,Ibuprofen ,Plasma protein binding ,010402 general chemistry ,01 natural sciences ,Molecular Docking Simulation ,chemistry.chemical_compound ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Binding site ,Serum Albumin ,Binding Sites ,Radiation ,Radiological and Ultrasound Technology ,biology ,010405 organic chemistry ,Chemistry ,Circular Dichroism ,Rational design ,Human serum albumin ,Protein Structure, Tertiary ,0104 chemical sciences ,Spectrometry, Fluorescence ,biology.protein ,Thermodynamics ,Salts ,Warfarin ,Protein Binding ,medicine.drug - Abstract
Triarylmethane derivatives are extensively investigated as antitumor and antibacterial drug candidates alone and as photoactivatable compounds. In the series of tris(1-alkylindol-3-yl)methylium salts (TIMs) these two activities differed depending on the length of N-alkyl chain, with C4-5 derivatives being the most potent compared to the shorter or longer chain analogs and to the natural compound turbomycin A (no N-substituent). Given that the human serum albumin (HSA) is a major transporter protein with which TIMs can form stable complexes, and that the formation of these complexes might be advantageous for phototoxicity of TIMs we determined the quantitative parameters of TIMs-HSA binding using spectroscopic methods and molecular docking. TIMs bound to HSA (1:1 stoichiometry) altered the protein's secondary structure by changing the α-helix/β-turn ratio. The IIa subdomain (Sudlow site I) is the preferred TIM binding site in HSA as determined in competition experiments with reference drugs ibuprofen and warfarin. The values of binding constants increased with the number of CH2 groups from 0 to 6 and then dropped down for C10 compound, a dependence similar to the one observed for cytocidal potency of TIMs. We tend to attribute this non-linear dependence to an interplay between hydrophobicity and steric hindrance, the two key characteristics of TIMs-HSA complexes calculated in the molecular docking procedure. These structure-activity relationships provide evidence for rational design of TIMs-based antitumor and antimicrobial drugs.
- Published
- 2016
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29. To the question on accuracy of forest heights’ measurements by the TanDEM-X radar interferometry data
- Author
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T. N. Chimitdorzhiev, M. E. Bykov, Yu. I. Kantemirov, I. I. Kirbizhekova, B. B. Labarov, and A. K. Baltukhaev
- Subjects
forest height ,validation ,satellite radiolocation ,Forestry ,SD1-669.5 ,differential interferometry - Abstract
The paper presents the validation results of the InSAR method for determining the forest canopy height, based on TanDEM-X and ALOS PALSAR data. The research conducted on the territory of the Baikal-Kudara forest area of the Republic of Buryatia (52°10'N, 106°48'E). Forest vegetation is represented mainly by conifers – pine, and spruce, with a small admixture of deciduous trees – aspen, birch, etc. The forest vegetation height was determined by subtracting the digital elevation model (DEM) of the digital terrain model (DTM). DEM is built according to the L-band (wavelength of 23.5 cm) ALOS PALSAR satellite with horizontal co-polarization mode. In the investigation it was assumed that a radar signal of ALOS PALSAR passes all forest thickness and reflected from the underlying surface, made it possible to recover terrain under forest canopy. DTM has been built using the TanDEM-X data (wavelength 3 cm). In this case, it was assumed that the radar echoes scattered from a some virtual phase centers of scattering surface, which characterizes the upper limit of the continuous forest canopy. To check the accuracy of satellite definitions of forest height in study area were made high-precision geodetic measurement of trees heights using electronic total station and the coordinates of geographic control points using differential GPS receivers. The discrepancy between the satellite and ground-based measurements at 11 test sites did not exceed 2 m, which is mainly due to the difference in measurement techniques: height of individual trees by ground methods and continuous forest canopy height using radar interferometry.
- Published
- 2016
30. Discovery of derivatives of 6(7)-amino-3-phenylquinoxaline-2-carbonitrile 1,4-dioxides: novel, hypoxia-selective HIF-1α inhibitors with strong antiestrogenic potency
- Author
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Danila V. Sorokin, Andrey E. Shchekotikhin, Lianet Monzote Fidalgo, Alexander M. Scherbakov, Galina I. Buravchenko, Alexander A. Korlukov, Lyubov G. Dezhenkova, Svetlana E. Solovieva, and Evgeny E. Bykov
- Subjects
Stereochemistry ,Poly ADP ribose polymerase ,Antineoplastic Agents ,Apoptosis ,01 natural sciences ,Biochemistry ,Structure-Activity Relationship ,chemistry.chemical_compound ,Quinoxaline ,Cell Line, Tumor ,Quinoxalines ,Diamine ,Nitriles ,Drug Discovery ,Humans ,Cytotoxicity ,Molecular Biology ,Cell Proliferation ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,Hypoxia-Inducible Factor 1, alpha Subunit ,Cell Hypoxia ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Receptors, Estrogen ,chemistry ,Cell culture ,Drug Screening Assays, Antitumor ,Tirapazamine ,K562 cells - Abstract
In this article, we describe the synthesis of 3-phenylquinoxaline-2-carbonitrile 1,4-dioxides bearing cyclic diamine residues at positions 6 or 7; the synthesis is based on the nucleophilic substitution of halogens. All synthesized 6(7)-aminoquinoxaline-2-carbonitrile 1,4-dioxides 3-6 demonstrated higher cytotoxicity and hypoxia selectivity compared to the reference agent tirapazamine against breast adenocarcinoma cell lines (MCF7, MDA-MB-231). The structure and position of the diamine residue considerably affects the antiproliferative properties of the quinoxaline-2-carbonitrile 1,4-dioxides. The introduction of a halogen atom at position 7 in the quinoxaline ring of 4a considerably increases the cytotoxicity of compounds 5a and 6a under both normoxic and hypoxic conditions. However, the most hypoxia-selective derivatives were non-halogenated 7-aminosubstituted 3-phenylquinoxaline-2-carbonitrile 1,4-dioxides 3a-j. Of the 32 novel synthesized derivatives, approximately 20 of the 6(7)-amino-3-phenylquinoxaline-2-carbonitrile 1,4-dioxides demonstrated high antiproliferative potency against wild type leukemia cells K562 and drug-resistant subline K562/4 with the expression of p-glycoprotein (p-gp) compared to the reference agent doxorubicin, which exhibited one order of magnitude lower activity towards K562/4 cells than towards K562 cells. Lead compounds 5a and 3f inhibited HIF-1α expression and activity and induced apoptosis in hypoxic tumor cells, which was confirmed by poly(ADP-ribose)polymerase (PARP) cleavage. Moreover, 5a and 3f showed strong antiestrogenic potencies in MCF7 breast cancer cells. Thus, the described series of quinoxaline 1,4-dioxides has high anticancer potential and good aqueous solubility. Therefore, these compounds are promising for further drug development of hypoxia-targeted anticancer agents.
- Published
- 2020
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31. The principles of designing automated systems for diagnostic monitoring of the engineering structures of hazardous production objects
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Yu. I. Steblev, S. V. Susarev, and D. E. Bykov
- Subjects
Engineering ,business.industry ,Engineering structures ,Mechanical Engineering ,Condensed Matter Physics ,Technical documentation ,Diagnostic monitoring ,Object (computer science) ,Structuring ,Mechanics of Materials ,Hazardous waste ,Systems engineering ,Production (economics) ,Process control ,General Materials Science ,business - Abstract
This article considers the basic principles of designing systems for monitoring engineering structures (SMESs) of hazardous production facilities, which have been formed based on the implementation of engineering designs of the SMESs of a number of large industrial oil-refining facilities. The proposed principles for designing SMESs as complex information diagnostic systems are based on strict logical structuring of huge volumes of information on monitoring objects: design documentation for the object itself and the automated process control system (APCS), safety and metrological provision requirements, and normative and technical documentation. It is shown that the basic stages and principles of SMES design can be formalized and logically described using the instrument of structural schemes.
- Published
- 2015
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32. DETECTION AND MONITORING OF GULLY FORMATIONS ON THE BASIS OF RADAR AND MULTISPECTRAL SATELLITE IMAGES
- Author
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M. E. Bykov, E. V. Malkhanova, A. V. Bazarov, and R. S. Sychev
- Subjects
Basis (linear algebra) ,law ,Multispectral image ,Satellite ,Radar ,Geology ,Remote sensing ,law.invention - Published
- 2018
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33. Enhancement of adhesive properties of road asphalts, waste oil processing products
- Author
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D. E. Bykov, A. A. Pimenov, V. Yu. Pivsaev, and P. E. Krasnikov
- Subjects
Fuel Technology ,Vegetable oil ,Waste management ,Geochemistry and Petrology ,Asphalt ,General Chemical Engineering ,Oil production ,Energy Engineering and Power Technology ,Environmental science ,Waste oil ,General Chemistry ,Adhesive - Abstract
In continuation of studies on the development of low-waste technologies for comprehensive utilization of oil production and refining waste, a method has been proposed for enhancement of the adhesive properties of secondary asphalt binders by introducing into their composition new amidoamine adhesive additives synthesized from soap stock, vegetable oil processing waste.
- Published
- 2015
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34. Macrolactones built from the bis-3,4(indol-1-yl)maleimide scaffold
- Author
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Maria N. Preobrazhenskaya, Yury N. Luzikov, Alexander M. Korolev, Evgeny E. Bykov, Alexander Y. Simonov, M. I. Reznikova, and Sergey A. Lakatosh
- Subjects
Quantum chemical ,Organic Chemistry ,Intramolecular cyclization ,Biochemistry ,Medicinal chemistry ,Toluene ,Gibbs free energy ,chemistry.chemical_compound ,symbols.namesake ,chemistry ,Intramolecular force ,Drug Discovery ,Indoline ,symbols ,Organic chemistry ,Dehydrogenation ,Maleimide - Abstract
15, 16, and 17-Membered lactones based on the bis-3,4(indol-1-yl)maleimide framework were obtained using intramolecular esterification reaction starting from 3-(1-ω-carboxyalkyl-2,3-dihydroindol-1-yl)-4-(1-ω-hydroxyalkyl-2,3-dihydroindol-1-yl)-maleimides. 3,4-Dibromo-maleimide, ω-(2,3-dihydroindol-3-yl)alkanoic acids, and ω-(2,3-dihydroindol-3-yl)alkanoles were used as starting compounds. Substitution of Br for the substituted indolines followed by the intramolecular cyclization of O-silylated hydroxyl acids derivatives led to macrolactones that incorporated 4-(dihydroindol-1-yl)-3-(indol-1-yl)maleimide moieties. Indoline nuclei in these compounds were dehydrogenated by DDQ in refluxing toluene to give 15, 16 or 17-membered lactones 3-[(ω-3-carboxyalkylindol-1-yl)-4-(ω-hydroxyalkylindol-1-yl)maleimides. Quantum chemical calculations showed that the formation of macrolactones of smaller size (13-membered) corresponds to the higher Gibbs energy ΔG# and correlates with the absence of the target reaction product.
- Published
- 2014
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35. Earth Surface Subsidence in the Kuznetsk Coal Basin Caused by Manmade and Natural Seismic Activity According to ALOS PALSAR Interferometry
- Author
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A. I. Zakharov, A. F. Emanov, Vladimir A. Cherepenin, M. E. Bykov, V. L. Mironov, V. S. Seleznev, M. I. Epov, and T. N. Chymitdorzhiev
- Subjects
Atmospheric Science ,business.industry ,Coal mining ,Subsidence ,Natural (archaeology) ,law.invention ,Earth surface ,Interferometry ,Spaceborne radar ,law ,Coal basin ,Computers in Earth Sciences ,Radar ,business ,Geomorphology ,Seismology ,Geology - Abstract
This paper presents results of a spaceborne radar interferometry technique application for land subsidence observations in a coal mining area in Kuzbass, Russia. Joint analysis of radar interferometry measurements with simultaneous seismic observations shows that the land subsidence is triggered by seismic events, both natural and caused by human underground activity. Surface displacements are linked typically to the boundaries of block structures and correlate with the location of clusters of seismic events.
- Published
- 2013
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36. Role of the acyl groups in carbohydrate chains in cytotoxic properties of olivomycin A
- Author
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Victor B Zbarsky, Alexander M. Vinogradov, Maria N. Preobrazhenskaya, Eugeniy E Bykov, Lyubov G. Dezhenkova, M. I. Reznikova, Nikita A. Durandin, Eugenia N. Olsufyeva, Vladimir A. Kuzmin, Alexander A. Shtil, and Anna N. Tevyashova
- Subjects
Circular dichroism ,Cations, Divalent ,Cell Survival ,Stereochemistry ,Carbohydrates ,Topoisomerase-I Inhibitor ,Residue (chemistry) ,chemistry.chemical_compound ,Cell Line, Tumor ,Drug Discovery ,Humans ,Magnesium ,Enzyme Inhibitors ,Cytotoxicity ,Pharmacology ,Antibiotics, Antineoplastic ,biology ,Chemistry ,Topoisomerase ,DNA ,Fluorescence ,DNA Topoisomerases, Type I ,biology.protein ,Olivomycin ,Olivomycins - Abstract
A series of olivomycin A derivatives containing different combinations of the acyl residues in the carbohydrate chains was obtained. The formation of complexes of Mg(2+)-coordinated dimers of these compounds with double-stranded DNA was studied using spectral methods such as absorption, fluorescence and circular dichroism (CD) spectral analyses. There was a good correlation of the values of binding constants of complexes (antibiotic)2Mg(2+)-DNA, the quantum yields of fluorescence and changes of the induced CD spectra with topoisomerase I inhibition and cytotoxicity. We demonstrate that the presence of the acyl groups in the saccharide residues of olivomycin A derivatives is absolutely necessary for a high cytotoxic potency of these antibiotics. On the basis of the experimental results and quantum chemical calculations, we presume that the acyl residue in the 4-O-position in the A-sugar residue is involved, to the most part, in the antibiotic-antibiotic interactions in the (olivomycin)2Mg(2+) dimers, whereas the O-acyl group in E-olivomicose residue largely participates in the formation of the (olivomycin)2Mg(2+)-DNA complexes.
- Published
- 2013
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37. Recovery of the diesel fraction of oil sludge by engaging in the deep hydrotreating process for manufacturing ultraclean diesel fuels
- Author
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D. E. Bykov, V. V. Ermakov, M. S. Kuznetsova, Andrey A. Pimerzin, A. A. Pimenov, P. A. Nikul’shin, V. Yu. Pivsaev, and M. V. Samsonov
- Subjects
General Chemical Engineering ,Vegetable oil refining ,Energy Engineering and Power Technology ,Fraction (chemistry) ,General Chemistry ,Raw material ,Pulp and paper industry ,Diesel fuel ,chemistry.chemical_compound ,Fuel Technology ,chemistry ,Geochemistry and Petrology ,Environmental science ,Petroleum ,Hydrodesulfurization ,Oil sludge ,Space velocity - Abstract
The possibility of involvement of diesel fractions obtained from petroleum waste in hydrotreating feedstock for the manufacture of diesel fuels that meet the Euro-4 and Euro-5 standards has been studied. The hydrogen treatment of a mixed feedstock, composed of diesel fractions of oil sludge (DFS), straight-run diesel fraction (SDF), and light catalytically cracked gas (LCCGO), conducted in a laboratory flow unit using the HTRU-120 CoMo/Al2O3 catalyst (340–360°C, 3.5 and 4.0 MPa, LHSV of 1.5–2.0 h−1, the hydrogen : feedstock ratios of 350 and 500 nL/L) has revealed that DFS can be used as a feedstock component for hydrotreating units used to manufacture diesel fuel that meets the Euro 4 and Euro 5 standards. If the process parameters of severe hydrogen treatment are maintained, as large an amount of DFS as 5 wt % can be involved in the hydrotreating unit feedstock. The samples of stabilized hydrogenation products obtained from this feedstock meet all the requirements of GOST (State Standard) R 52368-2005.
- Published
- 2013
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38. Pore-forming activity of new conjugate antibiotics based on amphotericin B
- Author
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Evgenia N Olsufyeva, Olga S. Ostroumova, E. E. Bykov, Svetlana S. Efimova, and Anna N. Tevyashova
- Subjects
0301 basic medicine ,030106 microbiology ,Cell Membranes ,Lipid Bilayers ,lcsh:Medicine ,Mycology ,Microbiology ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Antibiotics ,Microbial Control ,Amphotericin B ,Medicine and Health Sciences ,Vesicles ,Lipid bilayer ,lcsh:Science ,Pharmacology ,Liposome ,Antifungals ,Multidisciplinary ,Chemistry ,Antifungal antibiotic ,Antimicrobials ,lcsh:R ,Chemical modification ,Drugs ,Biology and Life Sciences ,Cell Biology ,Polyene ,Fluoresceins ,Combinatorial chemistry ,Lipids ,Anti-Bacterial Agents ,Calcein ,030104 developmental biology ,Membrane ,Microscopy, Fluorescence ,Liposomes ,Physical Sciences ,Phosphatidylcholines ,Lipid Bilayer ,lcsh:Q ,Cellular Structures and Organelles ,Conjugate ,Research Article ,Chemical Elements ,Hydrogen - Abstract
A series of amides of the antifungal antibiotic amphotericin B (AmB) and its conjugates with benzoxaboroles was tested to determine whether they form pores in lipid bilayers and to compare their channel characteristics. The tested derivatives produced pores of larger amplitude and shorter lifetime than those of the parent antibiotic. The pore conductance was related to changes in the partial charge of the hydrogens of the hydroxyl groups in the lactone ring that determined the anion coordination in the channel. Neutralization of one of the polar group charges in the AmB head during chemical modification produced a pronounced effect by diminishing the dwell time of the polyene channel compared to modification of both groups. In this study, compounds that had a modification of one carboxyl or amino group were less effective in initializing phase separation in POPC-membranes compared to derivatives that had modifications of both polar groups as well as the parent antibiotic. The effects were attributed to the restriction of the aggregation process by electrical repulsion between charged derivatives in contrast to neutral compounds. The significant correlation between the ability of derivatives to increase the permeability of model membranes-causing the appearance of single channels in lipid bilayers or inducing calcein leakage from unilamellar vesicles-and the minimal inhibitory concentration indicated that the antifungal effect of the conjugates was due to pore formation in the membranes of target cells.
- Published
- 2017
39. Derivatization of Aminoglycoside Antibiotics with Tris(2,6-dimethoxyphenyl)carbenium Ion
- Author
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A P, Topolyan, M A, Belyaeva, E E, Bykov, P V, Coodan, E A, Rogozhin, D A, Strizhevskaya, O M, Ivanova, A V, Ustinov, I V, Mikhura, I A, Prokhorenko, V A, Korshun, and A A, Formanovsky
- Subjects
trityl cation ,aminoglycoside antibiotics ,mass-spectrometry ,HPLC ,Molecular Biology ,Research Article - Abstract
Detection of aminoglycoside antibiotics by MS or HPLC is complicated, because a) carbohydrate molecules have low ionization ability in comparison with other organic molecules (particularly in MALDI-MS), and b) the lack of aromatics and/or amide bonds in the molecules makes common HPLC UV-detectors useless. Here, we report on the application of a previously developed method for amine derivatization with tris(2,6- dimethoxyphenyl)carbenium ion to selective modification of aminoglycoside antibiotics. Only amino groups bound to primary carbons get modified. The attached aromatic residue carries a permanent positive charge. This makes it easy to detect aminoglycoside antibiotics by MS-methods and HPLC, both as individual compounds and in mixtures.
- Published
- 2016
40. A novel acyclic oligomycin A derivative formed via retro-aldol rearrangement of oligomycin A
- Author
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Olga B. Bekker, Konstantin F. Turchin, Alexey S Trenin, Alexander M. Korolev, Valery N. Danilenko, Sergei M Elizarov, Maria N. Preobrazhenskaya, Lyubov G. Dezhenkova, Alexander A. Shtil, Evgenyi E Bykov, and Lyudmila N. Lysenkova
- Subjects
Spectrometry, Mass, Electrospray Ionization ,Magnetic Resonance Spectroscopy ,Oligomycin ,Spectrophotometry, Infrared ,Cell Survival ,Stereochemistry ,Antiparasitic ,medicine.drug_class ,Antineoplastic Agents ,Apoptosis ,Aldehyde ,chemistry.chemical_compound ,Aldol reaction ,Biosynthesis ,Drug Discovery ,medicine ,Humans ,Moiety ,Enzyme Inhibitors ,Pharmacology ,chemistry.chemical_classification ,Chloroform ,Molecular Structure ,ATP synthase ,biology ,fungi ,HCT116 Cells ,Anti-Bacterial Agents ,ATP Synthetase Complexes ,chemistry ,biology.protein ,Oligomycins ,Spectrophotometry, Ultraviolet ,K562 Cells - Abstract
The antibiotic oligomycin A in the presence of K(2)CO(3) and n-Bu(4)NHSO(4) in chloroform in phase-transfer conditions afforded a novel derivative through the initial retro-aldol fragmentation of the 8,9 bond, followed by further transformation of the intermediate aldehyde. NMR, MS and quantum chemical calculations showed that the novel compound is the acyclic oligomycin A derivative, in which the 8,9 carbon bond is disrupted and two polyfunctional branches are connected with spiroketal moiety in positions C-23 and C-25. The tri-O-acetyl derivative of the novel derivative was prepared. The acyclic oligomycin A derivative retained the ability to induce apoptosis in tumor cells at low micromolar concentrations, whereas its antimicrobial potencies decreased substantially. The derivative virtually lost the inhibitory activity against F(0)F(1) ATP synthase-containing proteoliposomes, strongly suggesting the existence of the target(s) beyond F(0)F(1) ATP synthase that is important for the antitumor potency of oligomycin A.
- Published
- 2012
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41. THE CASE OF Q-WAVE MYOCARDIAL INFARCTION IN A 35-YEARS-OLD FEMALE
- Author
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A. B. Tashtanaliev, M. K. Obraztsova, O. E. Bykov, and A. G. Pavlova
- Subjects
q-волновой инфаркт миокарда ,electrocardiography ,Science ,cardiovascular diseases ,q-wave myocardial infarction ,coronary angiography ,coronary heart disease in young women - Abstract
The article presents a case of Q-wave myocardial infarction, in a young woman of 35 years old. The patient complained. of pains not typical for angina pectoris. Therefore, the initial diagnosis was incorrect. After 3 months myocardial infarction, of cicatrization, stage was diagnosed. For definition, of further tactics of treatment we used, coronary angiography and recommended, stenting of critical stenosis on left anterior descending artery. For prophylactics of this case electrocardiography should, be routinely used, in all the cases of pain in the neck and. thorax in young women.
- Published
- 2012
42. Quantum-chemical study of triindolylmethylium salts dissociation in comparison with triphenyl-methyl chloride and its derivatives
- Author
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S. N. Lavrenov, E. E. Bykov, Maria N. Preobrazhenskaya, and N. D. Chuvylkin
- Subjects
Quantum chemical ,Triphenylmethane ,Organic Chemistry ,Inorganic chemistry ,Medicinal chemistry ,Chloride ,Heterolysis ,Dissociation (chemistry) ,chemistry.chemical_compound ,chemistry ,medicine ,Density functional theory ,Crystal violet ,medicine.drug - Abstract
Quantum-chemical calculations have been carried out of heterolytic dissociation energies of a series of tri(1H-indol-3-yl)methylium compounds with different counter-ions within the framework of density functional theory, using the functional B3LYP in the basis 6-31 + G(d). The results obtained have been compared with data calculated for unsubstituted triphenylmethane derivatives (triphenylmethylium chloride and methanesulfonate) and also for tri(4-dimethylaminophenyl)methylium chloride (crystal violet). Ionicity of tri(indol-3-yl)methylium salts is compared with that of crystal violet chloride and triphenylmethane derivatives.
- Published
- 2012
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43. Quantum-chemical study of nucleophilic substitution in protonated trisindolylmethane*
- Author
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Maria N. Preobrazhenskaya, S. N. Lavrenov, E. E. Bykov, and N. D. Chuvylkin
- Subjects
Quantum chemical ,Tris ,chemistry.chemical_compound ,Activation barrier ,Chemistry ,Computational chemistry ,Organic Chemistry ,Nucleophilic substitution ,Protonation ,Photochemistry ,Transition state ,Methane - Abstract
The total energies of reactants, products, and transition states of nucleophilic substitution reactions in protonated tris(indol-3-yl)methane have been assessed with the semiempirical AM1 method and the theory of functional density B3LYP/6-31(d) method. The results of calculations indicated that the reactions proceed by an S N 1-like mechanism, since the activation barrier for it is significantly lower than in the case of the S N 2-like mechanism.
- Published
- 2011
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- View/download PDF
44. Synthesis of 2-hetaryl-3-(indol-1-yl)-and -(3-pyrrol-1-yl)maleimides and study of their conversions under the action of protic acids*
- Author
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Maria N. Preobrazhenskaya, Sergey A. Lakatosh, and E. E. Bykov
- Subjects
Indole test ,Chemistry ,Organic Chemistry ,Organic chemistry ,Quantum chemistry - Abstract
A series of 3-(indol-1-yl)maleimides has been synthesized, substituted at position 2 by residues of amines or various nitrogenous heterocycles. The possibility of obtaining new polycondensed heterocyclic structures from them has been studied. Experimental investigations confirmed theoretical predictions made on the basis of results of quantum-chemical calculations.
- Published
- 2011
- Full Text
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45. Synthesis and cytotoxic potency of novel tris(1-alkylindol-3-yl)methylium salts: Role of N-alkyl substituents
- Author
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M. I. Reznikova, Valeria A. Glazunova, Victor V. Tatarsky, Maria N. Preobrazhenskaya, Evgeniy E. Bykov, S. N. Lavrenov, Evgenia V. Stepanova, Yulia L. Volodina, Yuriy N. Luzikov, and Alexander A. Shtil
- Subjects
chemistry.chemical_classification ,Indole test ,Tris ,Indoles ,Bicyclic molecule ,Stereochemistry ,Organic Chemistry ,Clinical Biochemistry ,Substituent ,Pharmaceutical Science ,Salt (chemistry) ,Antineoplastic Agents ,Biochemistry ,Chemical synthesis ,chemistry.chemical_compound ,chemistry ,Cell Line, Tumor ,Drug Discovery ,Side chain ,Humans ,Molecular Medicine ,Salts ,Methane ,Molecular Biology ,Alkyl - Abstract
Novel derivatives of tris(indol-3-yl)methane and tris(indol-3-yl)methylium salts with the alkyl substituents at the N-atoms of the indole rings were synthesized. An easy substitution of indole rings in trisindolylmethanes for other indoles under the action of acids is demonstrated, and the mechanism of substitution is discussed. To obtain trisindolylmethylium salts, the environmentally safe method of oxidation of trisindolylmethanes with air oxygen in acidic conditions was developed. Tris(1-alkylindol-3-yl)methanes and tris(1-alkylindol-3-yl)methylium salts represent three-bladed molecular propellers whose physico-chemical and biological properties strongly depend on the N -alkyl substituent. The cytotoxicity of novel compounds increased with the number of C atoms in the alkyl chains, with optimal number n = 3–5 whereas the derivatives with longer side chains were less cytotoxic. The most potent novel compounds killed human tumor cells at nanomolar-to-submicromolar concentrations, being one order of magnitude more potent than the prototype antibiotic turbomycin A [tris(indol-3-yl)methylium salt]. Apoptosis in HCT116 colon carcinoma cell line induced by tris(1-pentyl-1 H -indol-3-yl)methylium methanesulfonate was detectable at concentrations tolerable by normal blood lymphocytes. Thus, N -alkyl substituted tris(1-alkylindol-3-yl)methylium salts emerge as perspective anticancer drug candidates.
- Published
- 2010
- Full Text
- View/download PDF
46. The level of free radical oxidation products in heart and blood plasma in diabetes mellitus combined with chronic alcohol intoxication
- Author
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V. E. Vysokogorsky, A. V. Indutny, and D. E. Bykov
- Subjects
medicine.medical_specialty ,Thiobarbituric acid ,Clinical Biochemistry ,Oxidative phosphorylation ,medicine.disease ,Biochemistry ,Chronic alcohol ,chemistry.chemical_compound ,Endocrinology ,Alcohol intoxication ,chemistry ,Diabetes mellitus ,Internal medicine ,Free radical oxidation ,Blood plasma ,medicine ,Molecular Medicine ,Bioorganic chemistry - Abstract
The level of glycemia, contents of free radical oxidation products (thiobarbituric acid reactive substances, oxidatively modified proteins) have been investigated in blood plasma and heart of rats with diabetes mellitus subjected to chronic alcohol intoxication. Preexisting diabetes mellitus had no influence on the effect of chronic alcohol consumption on the blood plasma levels of oxidatively modified proteins, thiobarbituric acid reactive substances and glucose. However, the contents of thiobarbituric acid reactive substances and products of oxidative modification of proteins were significantly higher in hearts of diabetic rats with chronic alcohol intoxication than in diabetic rats without alcohol intoxication or in rats subjected to chronic alcohol treatment. The alcohol-induced hyperactivation of free radical processes found in the heart may have additional damaging effect.
- Published
- 2009
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47. Reaction of the antitumor antibiotic olivomycin I with aryl diazonium salts. Synthesis, cytotoxic and antiretroviral potency of 5-aryldiazenyl-6-O-deglycosyl derivatives of olivomycin I
- Author
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Jan Balzarini, Eugenyi E. Bykov, Maria N. Preobrazhenskaya, Eugenia N. Olsufyeva, Lyubov G. Dezhenkova, Alexander A. Shtil, Konstantin F. Turchin, and Anna N. Tevyashova
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Stereochemistry ,Clinical Biochemistry ,Pharmaceutical Science ,Microbial Sensitivity Tests ,Azo coupling ,Biochemistry ,Chemical synthesis ,chemistry.chemical_compound ,Electrophilic substitution ,Boric Acids ,Cell Line, Tumor ,Borates ,Drug Discovery ,Animals ,Humans ,Molecular Biology ,Cell Proliferation ,chemistry.chemical_classification ,Antibiotics, Antineoplastic ,Diazonium Compounds ,Azo compound ,Molecular Structure ,Aryl ,Organic Chemistry ,Combinatorial chemistry ,chemistry ,Viruses ,Proton NMR ,Molecular Medicine ,Olivomycin ,Olivomycins - Abstract
The azo coupling of the antibiotic olivomycin I (1) with aryl diazonium tetrafluoroborates produced 5-aryldiazenyl-6-O-deglycosyl derivatives of 1. The structures of new compounds were confirmed by (1)H NMR and mass spectrometry analysis. A quantum-chemical study was performed to analyze the possible directions of electrophilic substitution of 1 and the easiness of 6-O-disaccharide hydrolysis in the course of azo coupling. The antiproliferative and anti-retroviral activities of novel derivatives were studied.
- Published
- 2009
- Full Text
- View/download PDF
48. Quantum chemical study of the transformation of 2-(N-alkylamino)-3-(indol-1-yl)-and 2-(N-alkylamino)-3-(indol-3-yl)maleimides by protic acids: Tandem hydride transfer/cyclization mechanism
- Author
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Sergey A. Lakatosh, Maria N. Preobrazhenskaya, and E. E. Bykov
- Subjects
Indole test ,Reaction mechanism ,chemistry.chemical_compound ,Annulation ,Chemistry ,Hydride ,Stereochemistry ,Iminium ,Protonation ,General Chemistry ,Maleimide ,Transition state - Abstract
The geometric parameters, the charge distribution, and the energetics of N-methyl-2-(N-ethylanilino)-3-(indol-1-yl)-and N-methyl-2-(N-ethylanilino)-3-(indol-3-yl)maleimides and their conjugated acids were studied by density functional theory calculations at the B3LYP/6-31G(d) level. The mechanism of the tandem hydride transfer/cyclization sequence, which occurs after protonation of N-methyl-2-(N-ethylanilino)-3-(indol-1-yl)-and N-methyl-2-(N-ethylanilino)-3-(indol-3-yl)maleimides, was analyzed. The investigation of the potential energy surface for the tandem hydride transfer/cyclization of the iminium cation that formed upon protonation revealed that the hydride transfer followed by intramolecular cyclization at position 7 of the indole fragment in N-methyl-2-(N-ethylanilino)-3-(indol-1-yl)maleimide is the preferable process, unlike alternative intramolecular cyclization involving the cationic center at the C(2) atom of the indole fragment and the benzene ring of the N-ethylaniline fragment of the indoleninium cation in N-methyl-2-(N-ethylanilino)-3-(indol-3-yl)maleimide. A study of the key intermediates of the assumed reaction mechanism demonstrated that these intermediates are actually stationary points on the potential energy surface (minima and transition states).
- Published
- 2006
- Full Text
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49. Transformations of 3,4-bisindolylmaleimides with differently bonded indole and maleimide moieties under the action of protic acids: A quantum chemical study
- Author
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E. E. Bykov, Maria N. Preobrazhenskaya, and Sergey A. Lakatosh
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Indole test ,chemistry.chemical_compound ,Chemistry ,Activated complex ,Intramolecular force ,Electrophile ,Potential energy surface ,Protonation ,General Chemistry ,Photochemistry ,Maleimide ,Transition state - Abstract
Intramolecular cyclization reactions of 3,4-bis(indol-3-yl)maleimides 1, 3-(indol-1-yl)-4-(indol-3-yl)maleimides 2, and 3,4-bis(indol-1-yl)maleimides 3 under the action of protic acids were studied in order to estimate the parameters of the interaction between protonated and unprotonated indole moieties. Geometric parameters, charge distributions, energy characteristics, and information concerning the frontier orbitals of bisindolylmaleimides 1–3 were obtained from density functional B3LYP/6-31G(d) quantum chemical calculations. Alternative pathways of protonation of bisindolylmaleimides with differently bonded indole and maleimide moieties were studied and pathways of cyclization of corresponding conjugated acids leading to polyannelated compounds were analyzed. All the key intermediates of the cyclization reactions correspond to stationary points on the potential energy surfaces (minima and transition states). Analysis of the potential energy surfaces revealed almost linear dependences of the activation energies of the cyclization reactions under study on the distances between the reaction centers, on the angle of approach of intramolecular electrophile, and on the energy gap (energy difference between frontier orbitals). The key role in the cyclization reactions is played by structural similarity between the starting indoleninium cations and the activated complexes of the reactions under study.
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- 2006
- Full Text
- View/download PDF
50. Assessment of the stability of body functional systems in orienteers.
- Author
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E., CHEREPOV, V., EPISHEV, E., BYKOV, N., STOLIAROVA, and I., STOVBA
- Abstract
The article deals with developing a physiologically and psychologically justified program for improving functional stability in orienteers in the changing conditions of sports performance. The study was conducted from 2015 to 2018 on the premises of the scientific laboratory and in the field experiment. 25 orienteers (males and females) aged 17-20 years participated in the study. The experiment was conducted as a comprehensive control aimed at the assessment of the vestibular apparatus and physical and technical fitness of a functional and psychophysiological status in athletes. As a result of the experiment, all orienteers made a significant progress in the development of static and dynamic balance during the year of training. The results obtained in the experimental group in the platform balance test exceeded the initial data by 45.4% compared to 5.2% in the control group. The speed of sensorimotor reaction in athletes from the control group decreased by 4.3%, in the experimental group - by 16.7%. The results obtained for the critical frequency of flicker remained almost the same. Therefore, the improvement of the results obtained can be considered as a proof of the advantage of our method. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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