424 results on '"A. Yu. Egorov"'
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2. Development and characterization of patient-derived xenograft models of colorectal cancer for testing new pharmacological substances
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A. S. Goncharova, E. N. Kolesnikov, G. Yu. Egorov, A. Yu. Maksimov, A. N. Shevchenko, E. M. Nepomnyashchaya, D. Yu. Gvaldin, L. Z. Kurbanova, D. V. Khodakova, S. O. Kit, O. Yu. Kaymakchi, and A. V. Snezhko
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Molecular Medicine - Abstract
The aim of the study was to create a patient-derived xenograft (PDX) model of human colorectal cancer and to determine its histologic and molecular characteristics, such as the status of KRAS, NRAS, and BRAF genes and the presence of microsatellite instability.Materials and methods. First generation xenograft models in vivo were created using tumors from patients with colorectal cancer (n = 4) and immunodeficient Balb/c Nude mice (n = 20); second, third, and fourth generation models were created in the same mouse line (n = 3 for each generation). A caliper was used to measure subcutaneous xenografts; their size was calculated by the ellipsoid formula. Cryopreservation involved immersing the samples in a freezing medium (80% RPMI 1640, 10% fetal bovine serum, 10% dimethyl sulfoxide (DMSO)) and storing them at –80 °C. The histologic analysis was performed according to the standard technique (preparation of paraffin blocks and staining of microsections with hematoxylin and eosin). Mutations in the KRAS, NRAS, and BRAF genes were determined by direct Sanger sequencing; microsatellite instability was determined by the fragment analysis at five loci: Bat-25, Bat-26, NR21, NR24, and NR27.Results. Stable, transplantable xenografts of colorectal cancer were obtained from two out of four patients. The average waiting time from the implantation to the growth of the first generation xenograft was 28 days. The latency phase after cryopreservation was comparable to that at the creation of the first generation PDX model. The model reproduced the histotype, grade and mutational status of the KRAS, NRAS, and BRAF genes, as well as microsatellite instability of the donor tumor.Conclusion. The developed model of human colorectal cancer was characterized in terms of growth dynamics, cryopreservation tolerance, and histologic and molecular genetic parameters.
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- 2023
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3. Development of Local Governance in Modern Russia - Stages and Results
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Konstantin Yu. Egorov
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General Medicine - Published
- 2023
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4. Rapid Assessment of Neutralizing Antibodies Using Influenza Viruses with a Luciferase Reporter
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M V, Sergeeva, A A, Pulkina, E A, Romanovskaya-Romanko, A S, Mustafaeva, A Yu, Egorov, and M A, Stukova
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Applied Microbiology and Biotechnology ,Biochemistry - Abstract
Influenza viruses cause acute respiratory infections, especially in the autumn-winter period. They are characterized by a high mutation frequency and cause annual seasonal epidemics. The detection of antibodies that neutralize the virus is an important criterion in the assessment of population immunity and the influenza vaccine effectiveness. In this study, a method for determining the titer of virus-neutralizing antibodies in blood serum has been developed. A new test called the luciferase neutralization assay uses a bioluminescent signal for detection. The assay is based on engineered influenza reporter viruses with various surface antigens and a nanoluciferase reporter protein in the NS1 reading frame. Using the developed method, we studied paired sera of volunteers obtained before and after vaccination. The proposed assay was compared with the conventional antibody assessment methods (microneutralization and hemagglutination inhibition assay); a high degree of correlation was observed. At the same time, the use of the luciferase neutralization assay made it possible to reduce the time required for the analysis and to simplify the detection procedure.The online version contains supplementary material available at 10.1134/S0003683822070067.
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- 2022
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5. Comparative Study of the Behavior of Wistar Rats, Dopamine Transporter Heterozygous Rats and Rats after Long-Term Ethanol Consumption in the Morris Water Maze
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E. V. Filatova, G. E. Gromova, M. V. Dorofeikova, I. V. Antonova, and A. Yu. Egorov
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Physiology ,Biochemistry ,Ecology, Evolution, Behavior and Systematics - Published
- 2022
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6. Work of dissertation councils of new system of scientific attestation
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S. Yu. Egorov
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The paper is devoted to the consideration of the question of whether the Russian system of scientific attestation retains its integrity. The elimination of the monopoly of the Higher Attestation Commission (HAC) in matters of control over the activities of dissertation councils and procedures for defending dissertations made it possible to increase the variety of rules and practices of scientific attestation. Many scientific and educational organizations have developed their own regulations governing the corresponding activities. At the level of legislation, the instruction was fixed for the self-awarding of academic degrees to set requirements not lower than how they are formulated in federal acts. The question of how exactly this instruction is implemented is of research interest. In addition, it is important to understand whether applicants can receive equal rights and opportunities in different parts of the modern system. During the study, three existing subsystems were identified, together forming a single system. The first of them consists of ordinary and special dissertation councils, regulated directly by the Higher Attestation Commission and the Ministry of Science and Higher Education of Russia. The second subsystem is a collection of leading scientific and educational organizations that independently award academic degrees. Finally, the third subsystem consists of spiritual educational organizations, empowered to award theological degrees, which at the level of federal state educational standards are recognized as like other academic degrees. In all three subsystems, options for the defence of dissertations in permanent, one-time and joint dissertation councils were considered. Comparative analysis of regulatory and legal acts made it possible to highlight the similarities and differences of these subsystems, as well as to identify possible options for their development.
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- 2022
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7. High Power Single Mode 1300-nm Superlattice Based VCSEL: Impact of the Buried Tunnel Junction Diameter on Performance
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Sergey A. Blokhin, Andrey V. Babichev, Andrey G. Gladyshev, Leonid Ya. Karachinsky, Innokenty I. Novikov, Alexey A. Blokhin, Mikhail A. Bobrov, Nikolay A. Maleev, Vladislav V. Andryushkin, Dmitrii V. Denisov, Kirill O. Voropaev, Irina O. Zhumaeva, Victor M. Ustinov, Anton Yu. Egorov, and Nikolay N. Ledentsov
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Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics - Published
- 2022
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8. The Effect of Flight Overload on the Intra-Chamber Process in a Solid-Propellant Rocket Engine
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M. Yu. Egorov
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Aerospace Engineering - Published
- 2022
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9. An Analysis of Heat Transfer in Assemblies of Finned Heat-Exchange Elements
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V. D. Lychakov, M. Yu. Egorov, A. A. Scheglov, A. S. Sivovolov, A. S. Matyash, and B. F. Balunov
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Nuclear Energy and Engineering ,Energy Engineering and Power Technology - Published
- 2022
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10. Inhibition of growth of colorectal cancer patient-derived subcutaneous xenografts using combined Wnt signaling pathway inhibitor and 5‑fluorouracil
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A. S. Goncharova, A. V. Galina, D. V. Khodakova, G. Yu. Egorov, A. Yu. Maksimov, E. N. Kolesnikov, E. F. Komarova, A. A. Kiblitskaya, E. V. Zaikina, L. Z. Kurbanova, and M. V. Mindar
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General Arts and Humanities - Abstract
Purpose of the study. Was to analyze antitumor efficacy of the XAV 939 Wnt signaling pathway inhibitor and its combination with 5 fluorouracil in subcutaneous xenografts derived from patients with colorectal cancer.Materials and methods. Antitumor efficacy of the agents and their combination was studied in xenografts derived from patients with colorectal cancer and subcutaneously implanted in immunodeficient Balb/c Nude mice. All animals with tumors were divided into 4 groups (n = 5): group 1 received 5 fluorouracil 25 mg/kg, group 2 – XAV 939 25 mg/kg, group 3–5 fluorouracil and XAV 939 combination at the same dosages, group 4 was control. Criteria for the efficacy of the tested agents and their combination included tumor growth rate and tumor growth inhibition rate (TGI %).Results. The mean volumes of xenografts and tumor growth rate in the group receiving a combination of 5 fluorouracil and XAV 939 were 335.2 ± 40.7 mm3 , being lower than the averages of xenografts in controls – 609.3 ± 69.5 mm3 (p < 0.05). The mean volumes of xenografts in the group receiving 5 fluorouracil monotherapy were 601.9 ± 45.5 mm3 , in the group with the XAV 939 monotherapy – 527.9 ± 258.6 mm3 . The highest TGI (44.99 %) was registered in the group receiving a combination of 5 fluorouracil and XAV 939.Conclusion. The study revealed the ability of combined XAV 939 Wnt signaling pathway inhibitor and 5 fluorouracil to inhibit the growth of subcutaneous xenografts derived from patients with colorectal cancer.
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- 2022
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11. Quantum-Cascade Laser with Radiation Emission through a Textured Layer
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A. V. Babichev, E. S. Kolodeznyi, A.G. Gladyshev, D. V. Denisov, G. V. Voznyuk, M. I. Mitrofanov, D. A. Mikhailov, D. V. Chistyakov, D. I. Kuritsyn, V. V. Dudelev, S. O. Slipchenko, A. V. Lyutetskii, V. P. Evtikhiev, L. Ya. Karachinsky, I. I. Novikov, S. V. Morozov, G. S. Sokolovskii, N. A. Pikhtin, and A. Yu. Egorov
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Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2022
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12. The Effect of Light Intensity with a Mixed Spectrum on the Green Crops Productivity (at the Example of Watercress)
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Galina S. Kornilova and Maxim Yu. Egorov
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- 2022
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13. Surface Tension Measurements of Equiatomic Niti Alloy for the Melt Pool Simulation During Laser Powder Bed Fusion
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Stanislav Chernyshikhin, Sergey N. Zhevnenko, Andrey V. Zakirov, Boris A. Korneev, Dmitriy Ozherelkov, Sergey A. Belousov, Maria V. Bogdanova, Vladimir Yu. Egorov, and Igor V. Shishkovsky
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- 2023
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14. The results of anterior rectal resection with the formation of a hardware anastomosis in cancer patients
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E. N. Kolesnikov, A. V. Snezhko, V. S. Trifanov, M. A. Kozhushko, Yu. A. Fomenko, T. B. Katsieva, R. E. Myagkov, S. V. Sanamyanc, M. A. Averkin, and G. Yu. Egorov
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Purpose of the study. A retrospective analysis of the immediate results of performing anterior rectal resections in cancer. Materials and methods. In the Department of Abdominal Oncology No. 1 with a group of X-ray vascular methods of diagnosis and treatment of the clinic of the National Medical Research Centre for Oncology of the Ministry of Health of Russia treatment for rectal cancer operations of anterior rectal resection were performed in 334 patients, while in 143 (42.8 %) cases they were low. As a standard, total mesenteric excision and lymphoid dissection in volume D2 were performed. Combined surgical interventions were performed in 68 (20.4 %) patients for locally spread tumors. As a rule, they were resection in nature and were performed with tumor infiltration of adjacent organs (bladder with ureters, ovaries, uterus, vagina, small intestine, abdominal wall). Colorectal anastomosis using crosslinking devices was formed in all cases, in 316 (94.6 %) cases it was a "side – to-end" junction, in 18 patients – "end-to-end". A preventive proximal intestinal stoma was formed in 73 (21.9 %) cases, where 67 cases it was an ileostomy, and 6 – a transversostomy. The preventive proximal intestinal stoma was not formed among 261 patients. Results. After performing anterior resections for rectal cancer operations, the complications developed in 75 (22.5 %) patients. The most threatening and dangerous complication was the failure of the colorectal anastomosis, which was noted in 12 (3.5 %) cases.This complication occurred in 8.2 % (6 patients out of 73) of preventatively stoma-treated patients, in 2.3 % of patients without a stoma (6 patients out of 261).Conclusion. The use of a preventive proximal intestinal stoma allows you to form a colorectal anastomosis even in the presence of complicated forms of rectal cancer. The number of complications directly referred to the formation of a preventive proximal intestinal stoma is relatively small, but when planning surgery for uncomplicated rectal cancer, the probability of their possible occurrence should be taken into account.
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- 2021
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15. Anomalous Features of Dynamics of Intrachamber Processes in a Low-Thrust Solid Propellant Rocket Engine with a Multi-Grain Propellant Charge
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M. Yu. Egorov, D. M. Egorov, and S. M. Egorov
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Aerospace Engineering - Published
- 2021
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16. 20-Gbps 1300-nm range wafer-fused vertical-cavity surface-emitting lasers with InGaAs/InAlGaAs superlattice-based active region
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Sergey A. Blokhin, Andrey V. Babichev, Andrey G. Gladyshev, Innokenty I. Novikov, Alexey A. Blokhin, Mikhail A. Bobrov, Nikolay A. Maleev, Vladislav V. Andryushkin, Dmitrii V. Denisov, Kirill O. Voropaev, Victor M. Ustinov, Vladislav E. Bougrov, Anton Yu. Egorov, and Leonid Ya. Karachinsky
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General Engineering ,Atomic and Molecular Physics, and Optics - Published
- 2022
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17. Experimental Models of Cognitive Impairments in Schizophrenia
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N. N. Petrova, A. Yu. Egorov, E. O. Kutcher, and M. V. Dorofeikova
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Psychosis ,Schizophrenia ,General Neuroscience ,Genetic model ,medicine ,Behavioural sciences ,Cognition ,Psychopharmacology ,Cognitive skill ,Psychology ,medicine.disease ,Clinical psychology ,Psychopathology - Abstract
Cognitive impairments in schizophrenia are currently regarded as the third key group of symptoms, along with negative and productive psychopathological symptomatology. They are encountered in a majority of patients and determine the functional outcome of illness. This article presents a review of the literature on modeling of cognitive impairments in schizophrenia in animals. Pharmacological, ontogenetic, and genetic models are discussed, along with their mechanisms and characteristic manifestations, and methods of evaluating cognitive functions in rodents. There is now a multitude of methods for modeling individual cognitive impairments typical of schizophrenia patients in animals. These models are required for further development of psychopharmacology and studies of pathophysiological mechanisms, though none as yet allows the whole set and heterogenous structure of cognitive defi cit seen in patients to be reproduced. Particular attention is paid to ontogenetic models which can be used to study risk factors for the development of schizophrenia and early interventions in states posing high risks of developing psychosis.
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- 2021
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18. Surface Emitting Quantum-Cascade Ring Laser
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A. V. Babichev, E. S. Kolodeznyi, A. G. Gladyshev, D. V. Denisov, G. V. Voznyuk, M. I. Mitrofanov, N. Yu. Kharin, V. Yu. Panevin, S. O. Slipchenko, A. V. Lyutetskii, V. P. Evtikhiev, L. Ya. Karachinsky, I. I. Novikov, N. A. Pikhtin, and A. Yu. Egorov
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Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2021
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19. Surface Emitting Ring Quantum-cascade Lasers made by Focused Ion Beam Milling
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A.V. Babichev, D.A. Mikhailov, E.S. Kolodeznyi, A.G. Gladyshev, G.V. Voznyuk, M.I. Mitrofanov, S.O. Slipchenko, A.V. Lyutetskii, V.V. Dudelev, V.P. Evtikhiev, L. Ya. Karachinsky, I.I. Novikov, G.S. Sokolovskii, N.A. Pikhtin, and A. Yu. Egorov
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- 2022
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20. Research of the Program Injection Method for Determing the SEFI Cross Section of STM32 Microcontroller
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E.S. Makhinov, A. Yu. Egorov, I. O. Loskutov, and P.V. Nekrasov
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- 2022
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21. Influence of X-ray Source Spectrum on TID Degradation of CMOS Devices
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A. O. Teplyakova, A. Yu. Egorov, V. D. Kalashnikov, A. V. Ulanova, V. A. Marfin, and M. A. Rogovaia
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- 2022
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22. Optical Properties of Three-Dimensional InGaP(As) Islands Formed by Substitution of Fifth-Group Elements
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A. V. Babichev, N. V. Kryzhanovskaya, D. V. Denisov, A. G. Gladyshev, E. S. Kolodeznyi, Alexey M. Nadtochiy, A. Yu. Egorov, Innokenty I. Novikov, Anna S. Dragunova, L. Ya. Karachinsky, A. V. Uvarov, S. D. Komarov, and V. V. Andryushkin
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010302 applied physics ,Photoluminescence ,Materials science ,Annealing (metallurgy) ,Analytical chemistry ,Atmospheric temperature range ,Epitaxy ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Spectral line ,Electronic, Optical and Magnetic Materials ,010309 optics ,0103 physical sciences ,Photoluminescence excitation ,Spectroscopy ,Absorption (electromagnetic radiation) - Abstract
The optical properties of three-dimensional quantum-size InGaPAs islands, which are formed by substitution of phosphorous by arsenic in an InGaPAs layer deposited on GaAs directly during the epitaxial growth, are studied by photoluminescence (PL) spectroscopy. The PL line of the formed array of island lies in the range of 950–1000 nm at room temperature. The PL studies in the temperature range of 78–300 K indicate significant inhomogeneity of the island array, existence of nonradiative recombination centers, and transport of carriers between islands. The photoluminescence excitation spectra exhibit a line related to the absorption in the residual two-dimensional InGaPAs layer. Annealing of the structures allowed us to increase the PL intensity at room temperature up to 300% with a slight short-wavelength shift of the island emission line and to improve the homogeneity inside the island array.
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- 2021
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23. Rapid Neutralizing Antibody Assessment Using Influenza Viruses with Luciferase Reporter
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A. Yu. Egorov, Marina Stukova, E. A. Romanovskaya-Romanko, A.S. Mustafaeva, and A. A. Pulkina
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0301 basic medicine ,03 medical and health sciences ,030104 developmental biology ,Luciferase reporter ,Ecology ,biology ,030106 microbiology ,biology.protein ,Neutralizing antibody ,Applied Microbiology and Biotechnology ,Virology ,Biotechnology - Abstract
Influenza viruses cause an acute respiratory infection, especially in the autumn-winter period. They are characterized by a high mutation frequency and cause annual seasonal epidemics. The detection of virus-neutralizing antibodies is an important criterion in the assessment of population immunity and the influenza vaccine effectiveness. In this study, a method for determining the titer of virus-neutralizing antibodies in blood serum has been developed. A new test, called the luciferase neutralization assay, uses measurement of a bioluminescent signal as a detection method. The influenza A reporter viruses of various subtypes were constructed that encode the nanoluciferase protein in the non-structural NS1 protein reading frame. The developed method was used to compare paired sera of volunteers before and after their immunization with a seasonal influenza vaccine. The proposed method was also compared with certified antibody assay methods: neutralization reaction and hemagglutination inhibition reaction. The tests showed a high correlation, while the luciferase neutralization assay reduced the time and simplified the detection procedure. microneutralization, reporter virus, influenza virus, bioluminescence, nanoluciferase The study was supported by the grant of the President of the Russian Federation for young PhDs (no. 075-15-2019-226); and also by the grant of the Government of Saint-Petersburg for undergraduate and graduate students (September 25, 2018, no 124).
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- 2021
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24. DIMENSIONAL GENETIC RISK MARKERS OF INTERNET ADDICTIONIN YOUNG ADULTS
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N.V. Baranok, S.V. Grechany, V.A. Soldatkin, A.N. Yakovlev, A.E. Nikolishin, A.V. Trusova, A O Kibitov, E.M. Krupitsky, P.A. Ponizovsky, A. Yu. Egorov, K.V. Rybakova, M.G. Solovieva, N.A. Chuprova, T.V. Merkulova, and A.B. Shmukler
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Gerontology ,business.industry ,Medicine ,The Internet ,Genetic risk ,Young adult ,business - Published
- 2021
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25. Studying the Optical and Structural Properties of Three-Dimensional InGaP(As) Islands Formed by Substitution of Elements of the Fifth Group
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Innokenty I. Novikov, V. N. Nevedomskii, E. S. Kolodeznyi, V. V. Andryushkin, A. V. Babichev, A. G. Gladyshev, L. Ya. Karachinsky, D. V. Denisov, and A. Yu. Egorov
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010302 applied physics ,Materials science ,Physics and Astronomy (miscellaneous) ,Phosphorus ,Analytical chemistry ,chemistry.chemical_element ,Epitaxy ,01 natural sciences ,010305 fluids & plasmas ,chemistry ,Group (periodic table) ,0103 physical sciences ,Layer (electronics) ,Arsenic - Abstract
A new method for the formation of three-dimensional quantum-dimensional InGaP(As) islands is proposed, which consists in replacing phosphorus with arsenic in an InGaP layer deposited on GaAs directly during epitaxial growth. It is shown that the replacement of phosphorus with arsenic results in formation of three-dimensional islands in the thin InGaP layer. At room temperature, these islands emit light in the spectral range of 0.95–0.97 µm. The estimated density of the islands is 1.3 × 1010 cm–2.
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- 2020
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26. The Effect of a Saturable Absorber in Long-Wavelength Vertical-Cavity Surface-Emitting Lasers Fabricated by Wafer Fusion Technology
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A. A. Blokhin, Innokenty I. Novikov, D. V. Denisov, A. V. Babichev, M. A. Bobrov, Nikolai A. Maleev, S. S. Rochas, S. A. Blokhin, A. G. Kuzmenkov, L. Ya. Karachinsky, A. P. Vasil’ev, K. O. Voropaev, A. Yu. Egorov, V. M. Ustinov, A. S. Ionov, and A. G. Gladyshev
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010302 applied physics ,Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Physics::Optics ,Saturable absorption ,Optical power ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,law.invention ,Vertical-cavity surface-emitting laser ,Tunnel junction ,law ,0103 physical sciences ,Optoelectronics ,Wafer ,0210 nano-technology ,business ,Lasing threshold ,Molecular beam epitaxy - Abstract
An investigation has been performed of 1.55-μm vertical-cavity surface-emitting lasers based on heterostructures with a buried tunnel junction (BTJ) with a height difference of 15 nm. The devices are obtained by wafer fusion of heterostructures grown by molecular beam epitaxy and provide single-mode lasing at a BTJ diameter of up to 8 μm. A decrease in the BTJ size leads to a sharp increase in the threshold current, the output optical power, and the resonance frequency at the lasing threshold. Stable single-mode lasing takes place due to the smoothed boundary of the buried surface relief, which induces a gradual change in the profile of the effective refractive index in the lateral direction with the effective current confinement retained. This makes it possible to reduce significantly the transverse optical confinement factor for the higher-order modes even at a large BTJ size. However, at a small BTJ size, it leads to the formation of a saturable absorber in unpumped parts of the active region.
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- 2020
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27. Quantum-Cascade Ring Resonator Laser with 7–8 μm Wavelength and Surface Radiation Output
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V. P. Evtikhiev, M. I. Mitrofanov, D. I. Kuritsyn, E. S. Kolodeznyi, D. V. Denisov, G. V. Voznyuk, A. G. Gladyshev, A. V. Lyutetskii, Nikita A. Pikhtin, Anton Yu. Egorov, L. Ya. Karachinsky, A. V. Babichev, Sergey O. Slipchenko, Innokenty I. Novikov, and S. V. Morozov
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010302 applied physics ,Materials science ,business.industry ,Physics::Optics ,Heterojunction ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Laser ,Cladding (fiber optics) ,01 natural sciences ,Waveguide (optics) ,Focused ion beam ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,Wavelength ,Resonator ,Cascade ,law ,0103 physical sciences ,Optoelectronics ,0210 nano-technology ,business - Abstract
We have created a quantum-cascade laser with 7–8 μm wavelength and surface radiation output through a lattice formed by focused ion beam etching of the upper cladding of the waveguide. The active area of the quantum-cascade laser heterostructure was formed on the basis of the solid alloy heteropair In0.53Ga0.47As/Al0.48In0.52As with two-phonon depletion of the cascade lower level. We demonstrate laser generation in the spectral band 7–8 μm for the created lasers with the selective ring resonator. The studies of the generation spectra for the temperatures in 8–77 K range have shown, that the mode spacing in the generation spectra of these lasers correspond to the whispering-gallery modes.
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- 2020
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28. The Influence of the Parameters of a Short-Period InGaAs/InGaAlAs Superlattice on Photoluminescence Efficiency
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L. Ya. Karachinsky, A. Yu. Egorov, V. N. Nevedomskii, A. V. Babichev, D. V. Denisov, Innokenty I. Novikov, E. S. Kolodeznyi, A. G. Gladyshev, Vladislav E. Bougrov, S. S. Rochas, and V. V. Andryushkin
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010302 applied physics ,Photoluminescence ,Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Superlattice ,Physics::Optics ,Heterojunction ,02 engineering and technology ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,021001 nanoscience & nanotechnology ,Epitaxy ,01 natural sciences ,Vertical-cavity surface-emitting laser ,Condensed Matter::Materials Science ,0103 physical sciences ,Optoelectronics ,0210 nano-technology ,business ,Lasing threshold ,Quantum well ,Molecular beam epitaxy - Abstract
We have studied heterostructures based on short-period InGaAs/InGaAlAs superlattices (SLs) manufactured by molecular-beam epitaxy on InP substrates, intended for use as active regions in vertical-cavity surface-emitting lasers operating in a 1.3-μm spectral range. The heterostructures were characterized by measuring photoluminescence (PL) emission and X-ray diffraction. It is established that variation of the ratio of quantum-well and barrier-layer thicknesses in the SL allows controlled shift of the PL peak position for lasing in the 1.3-μm range at almost constant PL efficiency.
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- 2020
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29. Development and study of high-power quantum-cascade lasers emitting at 4.5 – 4.6 μm
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E. A. Kognovitskaya, G. M. Savchenko, A. V. Lyutetskii, D. V. Denisov, A. G. Gladyshev, S. N. Losev, Vladislav V. Dudelev, A. V. Babichev, L. Ya. Karachinsky, Grigorii S. Sokolovskii, I. I. Novikov, Sergey O. Slipchenko, Nikita A. Pikhtin, V. I. Kuchinskii, A. Yu. Egorov, and D. A. Mikhailov
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Physics ,business.industry ,Statistical and Nonlinear Physics ,Heterojunction ,Laser ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,Power (physics) ,law ,Cascade ,Optoelectronics ,Electrical and Electronic Engineering ,Quantum cascade laser ,business ,Quantum - Abstract
Quantum-cascade room-temperature 4.5 – 4.6 μm lasers with different numbers of quantum cascades are developed and studied. It is shown that losses at the metallised sidewalls of the ridge waveguide considerably increase the threshold current density. It is demonstrated that the current density needed to overcome the internal and outcoupling losses in lasers with 30 quantum cascades is an order of magnitude lower than in lasers with 15 quantum cascades.
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- 2020
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30. A Study of the Spatial-Emission Characteristics of Quantum-Cascade Lasers for the 8-μm Spectral Range
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Innokenty I. Novikov, V. Yu. Mylnikov, V. I. Kuchinskii, D. A. Mikhailov, Nikita A. Pikhtin, D. V. Denisov, A. Yu. Egorov, Sergey O. Slipchenko, Grigorii S. Sokolovskii, A. G. Gladyshev, E. A. Kognovitskaya, A. V. Babichev, L. Ya. Karachinsky, Vladislav V. Dudelev, A. V. Lyutetskii, and S. N. Losev
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010302 applied physics ,Materials science ,Multi-mode optical fiber ,Physics and Astronomy (miscellaneous) ,business.industry ,Physics::Optics ,Near and far field ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,Emission intensity ,law.invention ,Optics ,Cascade ,law ,0103 physical sciences ,Ridge (meteorology) ,0210 nano-technology ,Quantum cascade laser ,business ,Lasing threshold - Abstract
Near- and far-fields of quantum-cascade lasers emitting in the spectral range near 8 μm have been studied. For all laser samples with a ridge width of 20 and 50 μm, lasing on the fundamental waveguide mode with a divergence of ~50° was observed for all laser samples with a ridge width of 20 and 50 μm along the “fast” axis. Along the “slow” axis, a multimode lasing and a competition between the fundamental and higher waveguide modes, which is manifested for lasers with a ridge width of 50 μm in an increase in the emission divergence from ~10° near the threshold to >50° when the lasing threshold is exceeded by a factor of 2–3. The divergence along the “slow” axis for lasers with ridge width of 22 μm remained invariable in the whole range of pumping currents and equaled ~50°. That there is a substantial contribution from the fundamental mode to the total emission intensity of quantum-cascade lasers, which is apparent from the far-field intensity distribution pattern, cannot be established exclusively on the basis of results obtained in near-field measurements.
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- 2020
- Full Text
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31. 1.55-μm-Range Vertical-Cavity Surface-Emitting Lasers, Manufactured by Wafer Fusion of Heterostructures Grown by Solid-Source Molecular-Beam Epitaxy
- Author
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M. A. Bobrov, A. V. Babichev, S. N. Nevedomsky, S. S. Rohas, A. Yu. Egorov, A. G. Gladyshev, D. V. Denisov, A. A. Blokhin, A. G. Kuzmenkov, A P Vasyl’ev, K. O. Voropaev, L. Ya. Karachinsky, N. A. Maleev, V. M. Ustinov, Sergey A. Blokhin, Innokenty I. Novikov, and A. S. Ionov
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010302 applied physics ,Materials science ,business.industry ,Wafer bonding ,Heterojunction ,02 engineering and technology ,Substrate (electronics) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Epitaxy ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Vertical-cavity surface-emitting laser ,0103 physical sciences ,Surface roughness ,Optoelectronics ,Wafer ,0210 nano-technology ,business ,Molecular beam epitaxy - Abstract
The results are presented of a study and optimization of the conditions under which heterointerfaces of the GaAs–InGaAsP type are formed via the direct intermolecular wafer bonding (fusion) of a heterostructure of an active region on an InP substrate and distributed Bragg reflectors on GaAs substrates upon the fabrication of hybrid heterostructures for long-wavelength vertical-cavity surface-emitting lasers (VCSELs). The heterostructures are grown by solid-source molecular-beam epitaxy. It is shown that, in the case of the incomplete removal of oxide films during preparation of the wafers before fusion and/or in the presence of adsorbed water on the wafer surfaces, the fused interface contains a large number of amorphous inclusions, which are most likely oxides of Group-III elements. Optimization of the conditions in which a buried tunnel junction is formed on the surface of the heterostructure on an InP wafer made it possible to reduce the surface roughness to 1 nm and to ensure that the thickness of the GaAs–InGaAsP fused interface does not exceed 5 nm, with no dislocations or other extended defects found at the fused heterointerfaces. The 1.55-μm VCSELs fabricated from the hybrid heterostructures created using the developed technology demonstrate efficient lasing under continuous-wave pumping in a wide temperature range, which is indicative of the high optical quality of the fused heterointerfaces in the VCSEL structure.
- Published
- 2020
- Full Text
- View/download PDF
32. The Specifics of Design and Prediction of Thermohydraulic Characteristics of Thermosiphons
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S. V. Svetlov, V. I. Nikitin, B. F. Balunov, A. A. Shcheglov, S. B. Alekseev, V. A. Il’in, A. O. Borisov, A. S. Matyash, M. Yu. Egorov, and V. D. Lychakov
- Subjects
Materials science ,Countercurrent exchange ,Bubble ,Thermal resistance ,food and beverages ,Energy Engineering and Power Technology ,02 engineering and technology ,Mechanics ,complex mixtures ,01 natural sciences ,humanities ,010305 fluids & plasmas ,020401 chemical engineering ,Nuclear Energy and Engineering ,Cabin pressurization ,Mass transfer ,0103 physical sciences ,Heat transfer ,Thermal ,Thermosiphon ,0204 chemical engineering - Abstract
Recommendations are given on designing thermosiphons (TS) prepared on the basis of the experience that the authors gained in designing more than 4000 TSs for heat-recovery steam generators and the results of long-term investigations and tests carried out to study thermohydraulic and corrosion processes in vertical and inclined TSs filled with steam-water mixture. The results of similar studies performed by other authors are analyzed. References are given to the regulations on the design of heat transfer equipment for thermal and nuclear power stations. The requirements for TS construction materials, the degree of TS filling with water, and the TS vacuum level are outlined. Whether the evacuation of TS may be abandoned was assessed. Measures are proposed to prevent depressurization on water freezing in TSs. Recommendations are given on the calculation of thermohydraulic characteristics and steam-and-gas distribution in vertical or inclined TSs. The conditions of displacement by a steam flow of noncondensable gases, including air, to the top of the condensation zone in a thermosiphon are considered. Various regimes of axial heat transport and heat transfer are described for pure steam condensation (including film condensation, bubble condensation, distribution of different regimes of steam condensation, and condensate cooling along the height of the condensation zone during “flooding”). Heat transfer in the steam condensation from an air-steam mixture (the diffusion component of thermal resistance), maximum power, and the conditions for poorer cooling of the TS heating zone (“flooding,” steam separation at the upper generatrix of the heating zone in an inclined thermosiphon) are examined. Thermosiphons feature a countercurrent flow of steam and its condensate in a single flow with the same mass flowrates. Hence, a special case of “flooding” affecting the maximum power of the thermosiphon, the effect of the incoming steam flow on the heat transfer rate during film condensation, steam-and-gas distribution in a top-plugged channel, corrosion processes in thermosiphons, and hydrogen diffusion through the thermosiphon wall should also be studied.
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- 2020
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33. A Study of the Photoresponse in Graphene Produced by Chemical Vapor Deposition
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A. A. Vasiliev, V. Yu. Davydov, K. Yu. Shubina, A. V. Babichev, Ivan Mukhin, S. A. Kadinskaya, I. A. Eliseyev, A. Yu. Egorov, Eduard Moiseev, Sergey A. Blokhin, A. A. Blokhin, N. V. Kryzhanovskaya, and Pavel N. Brunkov
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Photocurrent ,Materials science ,Fabrication ,Condensed Matter::Other ,business.industry ,Graphene ,Physics::Optics ,Dielectric ,Chemical vapor deposition ,Condensed Matter Physics ,Distributed Bragg reflector ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,symbols.namesake ,law ,symbols ,Optoelectronics ,business ,Raman spectroscopy ,Layer (electronics) - Abstract
The results of experiments aimed at fabricating and studying the properties of photodetector structures based on single-layer graphene produced by chemical vapor deposition are presented. The configuration of a Ta2O5 vertical microcavity with a resonance wavelength of about 850 nm and a lower dielectric SiO2/Ta2O5 distributed Bragg reflector is taken as the base structure. The conditions for the transfer and fabrication of mesas in the graphene layer on the microcavity surface are optimized. The diagnostics by Raman spectroscopy of the structural quality of graphene after fabrication of the mesas in the graphene layer and contact pads are indicative of the single-layer structure of graphene with a low intensity of features in its spectrum, responsible for imperfection of the structure. The photocurrent is measured under local optical pumping.
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- 2020
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34. The influence of high ionizing dose rate on CMOS IC radiation hardness used in da-ta transmission elements
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Vladislav D. Kalashnikov, Pavel A. Balamutov, A.V. Sogoyan, Alexey Yu. Egorov, Andrey B. Karakozov, and A.V. Ulanova
- Subjects
Materials science ,lcsh:T58.5-58.64 ,business.industry ,lcsh:Information technology ,information security, radiation hardness, cmos vlsi, total dose effect, dose-rate ,General Medicine ,lcsh:Q350-390 ,Ionizing radiation ,CMOS ,Transmission (telecommunications) ,lcsh:Information theory ,Optoelectronics ,Dose rate ,business ,Radiation hardening - Abstract
In this work, the effect of the irradiation intensity on the radiation hardness of CMOS integrated circuits (ICs) was studied. We investigated 3 types of ICs manufactured according to design rules from 0.8 to 3 microns, and used in various information transmission systems: 1586IN4, HEF4093BT and MC14504B. The U-31/33 accelerator of electrons has been used for the study in both gamma-ray mode (for moderate intensity) and pulse electron generation mode (for high intensity). As a result, it was revealed that an increase in the intensity of exposure by 4 orders of magnitude might result in a radiation hardness decrease up to factor of 30. This circumstance has to be taken into account when testing CMOS ICs for radiation hardness to high intensity effects. The obtained experimental data confirm theoretical understanding of the influence of increased irradiation intensity on the dose hardness of CMOS ICs.
- Published
- 2020
35. A Vertical-Cavity Surface-Emitting Laser for the 1.55-μm Spectral Range with Tunnel Junction Based on n++-InGaAs/p++-InGaAs/p++-InAlGaAs Layers
- Author
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A. G. Kuzmenkov, V. M. Ustinov, A. V. Babichev, M. A. Bobrov, A. P. Vasil’ev, A. S. Ionov, L. Ya. Karachinsky, S. A. Blokhin, Innokenty I. Novikov, K. O. Voropaev, D. V. Denisov, Nikolai A. Maleev, A. Yu. Egorov, A. A. Blokhin, S. S. Rochas, and A. G. Gladyshev
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Materials science ,Fabrication ,Physics and Astronomy (miscellaneous) ,business.industry ,Epitaxy ,Laser ,law.invention ,Vertical-cavity surface-emitting laser ,Tunnel junction ,law ,Optical cavity ,Optoelectronics ,Wafer ,business ,Layer (electronics) - Abstract
A design of a tunnel junction (TJ) based on n++-InGaAs/p++-InGaAs/p++-InAlGaAs layers for vertical-cavity surface-emission lasers (VCSELs) for the 1.55-μm spectral range fabricated by wafer fusion of an InAlGaAsP/InP optical cavity and wafers with AlGaAs/GaAs distributed Bragg reflectors has been suggested and tested. The presence of the oxidation-resistant InGaAs layers makes it possible to employ the molecular-beam epitaxy in all stages of the fabrication technology of VCSELs, including the overgrowth of the surface profile in the TJ layer. Owing to the Burstein–Moss effect and to the thickness minimization of the p++-InGaAs layer, it was possible to avoid a buildup of the internal optical loss. As a result, the characteristics of the thus fabricated devices are comparable with those of VCSELs having an n++-/p++-InAlGaAs TJ and a similar level of the mirror losses.
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- 2020
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- View/download PDF
36. Spectral Characteristics of Half-Ring Quantum-Cascade Lasers
- Author
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L. Ya. Karachinsky, Innokenty I. Novikov, D. A. Firsov, D. V. Denisov, Nikita A. Pikhtin, A. Yu. Egorov, A. V. Lutetskiy, Vladislav V. Dudelev, L. E. Vorob’ev, E. S. Kolodeznyi, A. G. Gladyshev, A. S. Kurochkin, Grigorii S. Sokolovskii, D. A. Pashnev, Sergey O. Slipchenko, and A. V. Babichev
- Subjects
010302 applied physics ,Materials science ,business.industry ,Physics::Optics ,Radius ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,010309 optics ,Cascade ,law ,0103 physical sciences ,Spectral width ,Optoelectronics ,Whispering-gallery wave ,Photonics ,business ,Lasing threshold ,Free spectral range - Abstract
A cavity scheme based on a half-ring with different radii is proposed and fabricated for 7–8 μm quantum-cascade lasers. A quantum-cascade laser with a half-ring cavity radius of 191 μm demonstrated lasing with a spectral width of 474 nm (82 cm–1) at low temperatures. The free spectral range in these lasers was determined by the whispering gallery modes typical for ring cavities. The laser bandwidth at room temperature was 190 nm (31 cm–1), which may be related to an increase in the internal losses with increasing temperature. An increase in the cavity radius to 291 μm made it possible to achieve room-temperature lasing with whispering gallery modes and a bandwidth of 249 nm (40 cm–1) by reducing losses on the mirrors.
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- 2020
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37. Spectral Dynamics of Quantum Cascade Lasers Generating Frequency Combs in the Long-Wavelength Infrared Range
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Nikita A. Pikhtin, D. V. Denisov, A. G. Gladyshev, D. A. Mikhailov, V. I. Kuchinskii, E. A. Kognovitskaya, A. V. Babichev, A. V. Lyutetskii, Vladislav V. Dudelev, Grigorii S. Sokolovskii, A. Yu. Egorov, Innokenty I. Novikov, L. Ya. Karachinsky, S. N. Losev, and Sergey O. Slipchenko
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010302 applied physics ,Physics ,Range (particle radiation) ,Physics and Astronomy (miscellaneous) ,business.industry ,Infrared ,Physics::Optics ,Laser ,01 natural sciences ,010305 fluids & plasmas ,law.invention ,Pulse (physics) ,Frequency comb ,Optics ,Amplitude ,law ,Cascade ,0103 physical sciences ,Physics::Atomic Physics ,business ,Quantum - Abstract
We have studied the spectral and dynamic characteristics of quantum cascade lasers emitting in the long-wavelength infrared range. It is shown that lasers with a short cavity (~1 mm) make it possible to obtain frequency combs in a very wide spectral range. We have investigated the spectral dynamics in the frequency comb generation regime. It is demonstrated that the intensity of longitudinal laser modes varies during a pump pulse propagation. We have observed simultaneous generation of all longitudinal modes of a frequency comb over a pump pulse segment with a constant amplitude.
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- 2020
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38. Vaccination with virus-like particles containing hemagglutinin protects the lungs of mice with postifluenza bacterial pneumonia: virological, microbiological and clinical data
- Author
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I N, Falynskova, A Yu, Egorov, A V, Poddubikov, N O, Vartanova, N P, Kartashova, E A, Glubokova, V A, Mkhitarov, D S, Dzhalilova, O V, Makarova, and I A, Leneva
- Subjects
0301 basic medicine ,viruses ,030106 microbiology ,Hemagglutinin (influenza) ,Hemagglutinin Glycoproteins, Influenza Virus ,Antibodies, Viral ,medicine.disease_cause ,Virus ,Mice ,03 medical and health sciences ,Influenza A Virus, H1N1 Subtype ,0302 clinical medicine ,Virology ,Influenza, Human ,Streptococcus pneumoniae ,Pneumonia, Bacterial ,Animals ,Humans ,Medicine ,Vaccines, Virus-Like Particle ,030212 general & internal medicine ,Lung ,Mice, Inbred BALB C ,biology ,business.industry ,Bacterial pneumonia ,virus diseases ,General Medicine ,medicine.disease ,respiratory tract diseases ,Vaccination ,Titer ,Infectious Diseases ,Immunization ,biology.protein ,Viral disease ,business - Abstract
Introduction. Influenza is a severe viral disease, a frequent complication of which is a secondary bacterial pneumonia. Influenza vaccines prevent secondary bacterial complications. Virus-like particles are one of the promising areas for the development of new vaccines. The aim of this work is to study the correlation of the pathomorphological characteristics of the lungs with clinical, virological, and microbiological markers of the disease at vaccination with virus-like particles (VLPs), containing hemagglutinin (HA) of influenza virus (HA-Gag-VLPs) in a murine model of secondary bacterial pneumonia induced by S. pneumoniae after influenza infection. Material and methods. BALB/c mice were vaccinated with VLPs containing influenza HA. After 21 days, mice were infected with two strains of influenza viruses, homologous and non-homologous, and 5 days after viral infection, were infected with S. pneumoniae. The vaccination effect was evaluated by morphological, virological (titer of the virus in the lungs) and microbiological (titer of bacteria in the lungs) data, and was confirmed by clinical data (survival, change in body weight). Results. Immunization with HA-Gag-VLPs, followed by infection with a homologous influenza virus and S. pneumoniae, reduced the area of foci of inflammation, inhibited the replication of the virus and bacteria in the lungs, and also protected animals from death and reduced their weight loss. Immunization with HA-Gag-VLPs upon infection with a heterologous strain and S. pneumoniae did not affect these criteria. Conclusion. The immunization with HA-Gag-VLPs prevented the viral replication, providing a reduction of S. pneumoniae titer and the degree of lung damage, protecting animals from the disease in a murine model of secondary bacterial pneumonia, induced by S. pneumoniae, after influenza infection with homologous strain of the virus.
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- 2020
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- View/download PDF
39. Study of the Spectra of Arched-Cavity Quantum-Cascade Lasers
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A. V. Babichev, D. V. Denisov, Sergey O. Slipchenko, Yu. K. Bobretsova, Nikita A. Pikhtin, A. G. Gladyshev, L. Ya. Karachinsky, Leonid E. Vorobjev, A. Yu. Egorov, Innokenty I. Novikov, D. A. Pashnev, and D. A. Firsov
- Subjects
010302 applied physics ,Materials science ,business.industry ,Heterojunction ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Spectral line ,Electronic, Optical and Magnetic Materials ,law.invention ,010309 optics ,Wavelength ,chemistry.chemical_compound ,chemistry ,Cascade ,law ,0103 physical sciences ,Indium phosphide ,Optoelectronics ,Photonics ,business ,Lasing threshold - Abstract
The temperature characteristics of arched-cavity quantum-cascade lasers with different geometrical dimensions emitting in the spectral range of 7–8 μm are studied. The laser heterostructure was grown by molecular-beam epitaxy. The active region consisted of 50 cascades based on a heteropair of In0.53Ga0.47As/Al0.48In0.52As solid alloys. Single-mode lasing is demonstrated for lasers with the semicircular cavity segment 100 μm in diameter and the linear segment 1 mm long. The maximum side-mode suppression ratio at a temperature of 290 K was 26 dB, and the emission wavelength was 7.73 μm.
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- 2020
- Full Text
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40. Natural Circulation of a Fluid in a Thermosiphon Slightly Inclined to the Horizontal
- Author
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M. Yu. Egorov, B. F. Balunov, A. O. Borisov, V. D. Lychakov, A. A. Shcheglov, and A. S. Matyash
- Subjects
010302 applied physics ,Materials science ,Countercurrent exchange ,General Engineering ,Stratification (water) ,Mechanics ,Condensed Matter Physics ,01 natural sciences ,010305 fluids & plasmas ,Natural circulation ,0103 physical sciences ,Heat transfer ,Mass flow rate ,Generatrix ,Thermosiphon ,Porosity - Abstract
A pronounced stratification of the temperature (density) of the fluid over the cross section of the heating zone occurs in a thermosyphon that is slightly inclined to the horizontal and has a high degree of water filling, which leads to the onset of natural circulation of the medium along the length of the thermosiphon. In this case, there is an upward flow of water or a steam–water mixture in the upper part of the thermosiphon and a downward flow in the lower part. In experiments with a full-scale thermosiphon, the natural circulation in question increased the axial heat transfer through nonboiling water along all thermosiphon zones by three to seven times as compared to the heat transfer in a vertical thermosiphon. The estimated mass flow rate of natural circulation along the heating zone ranged from 25 to 105 kg/(m2 s). The heat-transfer coefficient and friction factor are estimated at the boundary of countercurrent water flows induced by natural circulation. The conditions of poorer cooling of the thermosiphon heating zone due to steam separation at its upper generatrix are examined. A decrease in the mass filling of the thermosiphon, i.e., an increase in the average void fraction of the medium in it, successively leads to the onset of bubbling steam condensation within the transport section and then in the cooling zone, with a decrease in the length of the upper section of nonboiling water. A transition to film condensation of steam occurs at the limit along the entire length of the cooling zone with a countercurrent steam flow and a near-wall film of its condensate above the level of the steam–water mixture in the thermosiphon.
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- 2020
- Full Text
- View/download PDF
41. Heterostructures of Quantum-Cascade Laser for the Spectral Range of 4.6 μm for Obtaining a Continuous-Wave Lasing Mode
- Author
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Innokenty I. Novikov, A. V. Babichev, L. Ya. Karachinsky, Grigorii S. Sokolovskii, A. V. Lyutetskii, D. V. Denisov, Vladislav V. Dudelev, Sergey O. Slipchenko, A. Yu. Egorov, Nikita A. Pikhtin, and A. G. Gladyshev
- Subjects
010302 applied physics ,Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Superlattice ,Physics::Optics ,Heterojunction ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,Cladding (fiber optics) ,01 natural sciences ,law.invention ,Condensed Matter::Materials Science ,chemistry.chemical_compound ,chemistry ,law ,0103 physical sciences ,Indium phosphide ,Optoelectronics ,Continuous wave ,0210 nano-technology ,business ,Quantum cascade laser ,Lasing threshold - Abstract
The method of molecular-beam epitaxy was used to fabricate an elastically balanced heterostructure of a quantum-cascade laser for the spectral range of 4.6 μm based on a heteropair of solid alloys, In0.67Ga0.33As/In0.36Al0.64As, and indium phosphide layers serving as waveguide cladding layers. An X-ray diffraction analysis demonstrated the high uniformity of the composition and thickness of layers in cascades of the heterostructure over the substrate area. Lasers with four cleaved facets show lasing at room temperature at a wavelength close to 4.6 μm with a comparatively low threshold current density of 1.1 kA/cm2.
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- 2020
- Full Text
- View/download PDF
42. Quantum-Cascade Lasers with a Distributed Bragg Reflector Formed by Ion-Beam Etching
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L. E. Vorob’ev, D. V. Denisov, A. G. Gladyshev, M. I. Mitrofanov, Innokenty I. Novikov, D. A. Firsov, V. P. Evtikhiev, D. A. Pashnev, A. V. Babichev, G. V. Voznyuk, Nikita A. Pikhtin, A. Yu. Egorov, and L. Ya. Karachinsky
- Subjects
010302 applied physics ,Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Physics::Optics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,Distributed Bragg reflector ,Cladding (fiber optics) ,01 natural sciences ,law.invention ,law ,Cascade ,Etching (microfabrication) ,0103 physical sciences ,Optoelectronics ,0210 nano-technology ,Quantum cascade laser ,business ,Waveguide ,Lasing threshold - Abstract
Single-mode lasing of quantum-cascade lasers with a distributed Bragg reflector formed by ion-beam etching in layers of the upper waveguide cladding is demonstrated. The active region is formed based on an In0.53Ga0.47As/Al0.48In0.52As solid-alloy heteropair with two-phonon depletion of the lower level in the cascade. Single-mode lasing at a temperature of 280 K corresponds to the emission wavelength of 7.74 μm, and the side-mode suppression ratio is 24 dB.
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- 2020
- Full Text
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43. Controlled Neuroplasticity
- Author
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A. G. Naryshkin, I. V. Galanin, and A. Yu. Egorov
- Subjects
Physiology ,Physiology (medical) - Published
- 2020
- Full Text
- View/download PDF
44. 1300-nm wafer-fused VCSELs with InGaAs/InAlGaAs superlattice-based active region
- Author
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Sergey A. Blokhin, Nikolay Ledentsov, Stanislav S. Rochas, Andrey V. Babichev, Andrey G. Gladyshev, Lukasz Chorchos, Oleg Y. Makarov, Leonid Ya Karachinsky, Innokenty I. Novikov, Alexey A. Blokhin, Mikhail A. Bobrov, Nikolay A. Maleev, Vladislav V. Andryushkin, Kirill O. Voropaev, Irina O. Zhumaeva, Victor M. Ustinov, Anton Yu. Egorov, and Nikolay N. Ledentsov
- Published
- 2022
- Full Text
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45. Anabar–Lena Composite Tectono-Sedimentary Element, northern East Siberia
- Author
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A. K. Khudoley, S. V. Frolov, G. G. Akhmanov, E. A. Bakay, S. S. Drachev, A. Yu Egorov, V. B. Ershova, N. I. Korobova, N. S. Shevchuk, and M. A. Rogov
- Subjects
Geology - Abstract
The Anabar–Lena Composite Tectono-Sedimentary Element (AL CTSE) is located in northern East Siberia extending for c. 700 km along the Laptev Sea coast between the Khatanga Bay and Lena River delta. The AL CTSE consists of rocks from the Mesoproterozoic to Late Cretaceous in age with the total thickness reaching 14 km. It evolved through the following tectonic settings: (1) Meso-Early Neoproterozoic intracratonic basin; (2) Ediacaran–Early Devonian passive margin; (3) Middle Devonian–Early Carboniferous rift; (4) late Early Carboniferous–latest Jurassic passive margin; (5) Permian foreland basin; (6) Triassic to Jurassic continental platform basin; and (7) latest Jurassic–earliest Late Cretaceous foreland basin. Proterozoic and lower–middle Paleozoic successions are composed mainly of carbonate rocks, while siliciclastic rocks dominate upper Paleozoic and Mesozoic sections. Several petroleum systems are assumed in the AL CTSE. Permian source rocks and Triassic sandstone reservoirs are the most important play elements. The presence of several mature source rock units and abundant oil and gas shows (both in wells and in outcrops), including the giant Olenek Bitumen Field, suggests that further exploration in this area may result in economic discoveries.
- Published
- 2022
- Full Text
- View/download PDF
46. High-power quantum-cascade lasers for 8 µm spectral region
- Author
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V.V. Dudelev, D.A. Mikhailov, E.D. Cherotchenko, D.V. Chistyakov, A.V. Babichev, V. Yu. Mylnikov, A.G. Gladyshev, S.N. Losev, I.I. Novikov, A.V. Lyutetskiy, S.O. Slipchenko, N.A. Pikhtin, L. Ya. Karachinsky, A. Yu. Egorov, and G.S. Sokolovskii
- Abstract
Combination of phosphorus-free molecular beam epitaxy (MBE) with metal-organic chemical vapor deposition (MOCVD) enabled record-high power quantum-cascade lasers (QCLs) for 8µm spectral region with total output power of over 16W under pulsed pumping.
- Published
- 2022
- Full Text
- View/download PDF
47. THE STRUCTURE OF 'FATHER' IN THE NOVEL 'GOOD NIGHT' BY A. TERTS (A. D. SINYAVSKY)
- Author
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Mikhail Yu. Egorov
- Subjects
Physics ,Crystallography ,Structure (category theory) - Abstract
The article demonstrates how the chapter of the “Father” of the novel by A. Terts (A. D. Sinyavsky) “Good Night” is structured, shows how the image of the protagonist's father is built. The storylines of the son and father in the chapter are made in such a way that they rely on typologically similar elements, which largely determine the behavior, characters. In the fate of both, a bicycle and a gun play an important role; at the same time, they acquire new acquaintances of children; their fates were influenced by books; both are prone to invention; revolutionary, arrested. The father seems to help his son to penetrate the secrets of literary skill. The chapter “Father” is presented in such a way as to reflect judgments about literary work that Sinyavsky had a conversation with his father. The author refuses a linear, consistent narrative (for example, within several lines, events that fall on several decades may collide). The concept of mystery plays an important role in the narrative. At the same time, such a secret is important in the chapter, which will be exposed by its carriers. The original narrative in “Good Night” allows you to control both the narrator's awareness of the father and the degree of awareness of the reader. Avoiding a linear, consistent, “rational” narrative, A. D. Sinyavsky postulates the failure of such a story about human fate, where it is thought of as organically whole.
- Published
- 2020
- Full Text
- View/download PDF
48. CHARACTERISTICS OF SEMI-FORCED ALCOHOL CONSUMPTION IN RATS HETEROZYGOUS (DAT-HET) FOR THE DOPAMINE TRANSPORTER (DAT) GENE KNOCKOUT: A PILOT STUDY
- Author
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Anastasia E Veraksa, I.V. Antonova, and A. Yu. Egorov
- Subjects
medicine.medical_specialty ,Endocrinology ,biology ,Internal medicine ,medicine ,biology.protein ,Alcohol consumption ,Gene knockout ,Dopamine transporter - Published
- 2020
- Full Text
- View/download PDF
49. GENETIC MARKERS OF INTERNET ADDICTION RISK: ASSOCIATION WITH MEDICAL HISTORY AND CLINICAL CHARACTERISTICS
- Author
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S.V. Grechany, A. Yu. Egorov, N.A. Chuprova, and A O Kibitov
- Subjects
medicine.medical_specialty ,business.industry ,Genetic marker ,Addiction ,media_common.quotation_subject ,Association (object-oriented programming) ,Medicine ,Medical history ,The Internet ,business ,Psychiatry ,media_common - Published
- 2020
- Full Text
- View/download PDF
50. INTERNET ADDICTION IN YOUNG ADULTS: TYPES OF ONLINE ACTIVITIES, GENDER DIFFERENCES, COMORBID MENTAL AND SUBSTANCE USE DISORDERS
- Author
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S.V. Grechaniy, V.A. Soldatkin, A.B. Shmukler, A. Yu. Egorov, R.D. Ilyuk, and A.N. Yakovlev
- Subjects
medicine.medical_specialty ,business.industry ,Addiction ,media_common.quotation_subject ,medicine ,The Internet ,Young adult ,Substance use ,Psychiatry ,business ,Psychology ,media_common - Published
- 2020
- Full Text
- View/download PDF
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