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1. Ultrafast neural sampling with spiking nanolasers

Author

Boikov, Ivan K., de Rossi, Alfredo, and Petrovici, Mihai A.

Subjects
Physics - Optics
Abstract

Owing to their significant advantages in terms of bandwidth, power efficiency and especially speed, optical neuromorphic systems have arisen as interesting alternatives to conventional semiconductor devices. Recently, photonic crystal nanolasers with excitable behaviour were first demonstrated. Depending on the pumping strength, they emit short optical pulses -- spikes -- at various intervals on a nanosecond timescale. In this theoretical work, we show how networks of such photonic spiking neurons can be used for Bayesian inference through sampling from learned probability distributions. We provide a detailed derivation of translation rules from conventional sampling networks such as Boltzmann machines to photonic spiking networks and demonstrate their functionality across a range of generative tasks. Finally, we provide estimates of processing speed and power consumption, for which we expect improvements of several orders of magnitude over current state-of-the-art neuromorphic systems., Comment: 13 pages, 9 figures

Published
2025

2. Characterization of the optical model of the T2K 3D segmented plastic scintillator detector

Author

Abe, S., Alekseev, I., Arai, T., Arihara, T., Arimoto, S., Babu, N., Baranov, V., Bartoszek, L., Berns, L., Bhattacharjee, S., Blondel, A., Boikov, A. V., Buizza-Avanzini, M., Capó, J., Cayo, J., Chakrani, J., Chong, P. S., Chvirova, A., Danilov, M., Davis, C., Davydov, Yu. I., Dergacheva, A., Dokania, N., Douqa, D., Doyle, T. A., Drapier, O., Eguchi, A., Elias, J., Fedorova, D., Fedotov, S., Ferlewicz, D., Fuji, Y., Furui, Y., Gendotti, A., Germer, A., Giannessi, L., Giganti, C., Glagolev, V., Hu, J., Iwamoto, K., Jakkapu, M., Jesús-Valls, C., Ji, J. Y., Jung, C. K., Kakuno, H., Kasetti, S. P., Kawaue, M., Khabibullin, M., Khotjantsev, A., Kikawa, T., Kikutani, H., Kobayashi, H., Kobayashi, T., Kodama, S., Kolupanova, M., Korzenev, A., Kose, U., Kudenko, Y., Kuribayashi, S., Kutter, T., Lachat, M., Lachner, K., Last, D., Latham, N., Silverio, D. Leon, Li, B., Li, W., Li, Z., Lin, C., Lin, L. S., Lin, S., Lux, T., Mahtani, K., Maret, L., Caicedo, D. A. Martinez, Martynenko, S., Matsubara, T., Mauger, C., McGrew, C., McKean, J., Mefodiev, A., Miller, E., Mineev, O., Moreno, A. L., Muñoz, A., Nakadaira, T., Nakagiri, K., Nguyen, V., Nicola, L., Noah, E., Nosek, T., Okinaga, W., Osu, L., Paolone, V., Parsa, S., Pellegrino, R., Ramirez, M. A., Reh, M., Ricco, C., Rubbia, A., Sakashita, K., Sallin, N., Sanchez, F., Schefke, T., Schloesser, C. M., Sgalaberna, D., Shvartsman, A., Skrobova, N., Speers, A. J., Suslov, I. A., Suvorov, S., Svirida, D., Tairafune, S., Tanigawa, H., Teklu, A., Tereshchenko, V. V., Tzanov, M., Vasilyev, I. I., Wallace, H. T., Whitney, N., Wood, K., Xu, Y. -h., Yang, G., Yershov, N., Yokoyama, M., Yoshimoto, Y., Zhao, X., Zheng, H., Zhu, T., Zilberman, P., and Zimmerman, E. D.

Subjects
High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

The magnetised near detector (ND280) of the T2K long-baseline neutrino oscillation experiment has been recently upgraded aiming to satisfy the requirement of reducing the systematic uncertainty from measuring the neutrinonucleus interaction cross section, which is the largest systematic uncertainty in the search for leptonic charge-parity symmetry violation. A key component of the upgrade is SuperFGD, a 3D segmented plastic scintillator detector made of approximately 2,000,000 optically-isolated 1 cm3 cubes. It will provide a 3D image of GeV neutrino interactions by combining tracking and stopping power measurements of final state particles with sub-nanosecond time resolution. The performance of SuperFGD is characterized by the precision of its response to charged particles as well as the systematic effects that might affect the physics measurements. Hence, a detailed Geant4 based optical simulation of the SuperFGD building block, i.e. a plastic scintillating cube read out by three wavelength shifting fibers, has been developed and validated with the different datasets collected in various beam tests. In this manuscript the description of the optical model as well as the comparison with data are reported., Comment: 31 pages, 15 figures

Published
2024

3. Nonlinear integrated optical resonators for optical fibre data recovery

Author

Boikov, Ivan K., Brunner, Daniel, and De Rossi, Alfredo

Subjects
Physics - Optics, Physics - Applied Physics
Abstract

We apply in simulation a reservoir computer based on evanescently coupled GaAs microrings for real-time compensation of a nonlinear distortion of a 50 Gbaud 16-QAM signal with the launch power up to 12 dBm in a standard single-mode optical fibre. We clearly evidence the crucial role of fast nonlinear response in enabling all-optical signal recovery in real time. With our system we are able to reduce the signal error rate below the forward error correction limit for a 20 km fibre and 12 dBm launch power., Comment: 13 pages, 5 figures

Published
2024

4. Technical Design Report of the Spin Physics Detector at NICA

Author

The SPD Collaboration, Abazov, V., Abramov, V., Afanasyev, L., Akhunzyanov, R., Akindinov, A., Alekseev, I., Aleshko, A., Alexakhin, V., Alexeev, G., Alimov, L., Allakhverdieva, A., Amoroso, A., Andreev, V., Andronov, E., Anikin, Yu., Anischenko, S., Anisenkov, A., Anosov, V., Antokhin, E., Antonov, A., Antsupov, S., Anufriev, A., Asadova, K., Ashraf, S., Astakhov, V., Aynikeev, A., Azarkin, M., Azorskiy, N., Bagulya, A., Baigarashev, D., Baldin, A., Baldina, E., Barbashina, N., Barnyakov, A., Barsov, S., Bartkevich, A., Baryshevsky, V., Basharina, K., Baskakov, A., Baskov, V., Batista, M., Baturitsky, M., Bautin, V., Bedareva, T., Belokurova, S., Belova, A., Belyaeva, E., Berdnikov, A., Berdnikov, Ya., Berezhnoy, A., Berngardt, A., Bespalov, Yu., Bleko, V., Bliznyuk, L., Bogoslovskii, D., Boiko, A., Boikov, A., Bolsunovskya, M., Boos, E., Borisov, V., Borsch, V., Budkouski, D., Bulanova, S., Bulekov, O., Bunichev, V., Burtebayev, N., Bychanok, D., Casanova, A., Cesar, G., Chemezov, D., Chepurnov, A., Chen, L., Chmill, V., Chukanov, A., Chuzo, A., Danilyuk, A., Datta, A., Dedovich, D., Demichev, M., Deng, G., Denisenko, I., Denisov, O., Derbysheva, T., Derkach, D., Didorenko, A., Dima, M. -O., Doinikov, A., Doronin, S., Dronik, V., Dubinin, F., Dunin, V., Durum, A., Egorov, A., El-Kholy, R., Enik, T., Ermak, D., Erofeev, D., Erokhin, A., Ezhov, D., Fedin, O., Fedotova, Ju., Feofilov, G., Filatov, Yu., Filimonov, S., Frolov, V., Galaktionov, K., Galoyan, A., Garkun, A., Gavrishchuk, O., Gerasimov, S., Gerassimov, S., Gilts, M., Gladilin, L., Golovanov, G., Golovnya, S., Golovtsov, V., Golubev, A., Golubykh, S., Goncharov, P., Gongadze, A., Greben, N., Gregoryev, A., Gribkov, D., Gridin, A., Gritsay, K., Gubachev, D., Guo, J., Gurchin, Yu., Gurinovich, A., Gurov, Yu., Guskov, A., Gutierrez, D., Guzman, F., Hakobyan, A., Han, D., Harkusha, S., Hu, Sh., Igolkin, S., Isupov, A., Ivanov, A., Ivanov, N., Ivantchenko, V., Jin, Sh., Kakurin, S., Kalinichenko, N., Kambar, Y., Kantsyrev, A., Kapitonov, I., Karjavine, V., Karpishkov, A., Katcin, A., Kekelidze, G., Kereibay, D., Khabarov, S., Kharyuzov, P., Khodzhibagiyan, H., Kidanov, E., Kidanova, E., Kim, V., Kiryanov, A., Kishchin, I., Kokoulina, E., Kolbasin, A., Komarov, V., Konak, A., Kopylov, Yu., Korjik, M., Korotkov, M., Korovkin, D., Korzenev, A., Kostenko, B., Kotova, A., Kotzinian, A., Kovalenko, V., Kovyazina, N., Kozhin, M., Kraeva, A., Kramarenko, V., Kremnev, A., Kruchonak, U., Kubankin, A., Kuchinskaia, O., Kulchitsky, Yu., Kuleshov, S., Kulikov, A., Kulikov, V., Kurbatov, V., Kurmanaliev, Zh., Kurochkin, Yu., Kutuzov, S., Kuznetsova, E., Kuyanov, I., Ladygin, E., Ladygin, V., Larionova, D., Lebedev, V., Levchuk, M., Li, P., Li, X., Li, Y., Livanov, A., Lednicki, R., Lobanov, A., Lobko, A., Loshmanova, K., Lukashevich, S., Luschevskaya, E., Lyashko, A. L'vov I., Lysan, V., Lyubovitskij, V., Madigozhin, D., Makarenko, V., Makarov, N., Makhmanazarov, R., Maleev, V., Maletic, D., Malinin, A., Maltsev, A., Maltsev, N., Malkhasyan, A., Malyshev, M., Mamoutova, O., Manakonov, A., Marova, A., Merkin, M., Meshkov, I., Metchinsky, V., Minko, O., Mitrankov, Yu., Mitrankova, M., Mkrtchyan, A., Mkrtchyan, H., Mohamed, R., Morozova, S., Morozikhin, A., Mosolova, E., Mossolov, V., Movchan, S., Mukhamejanov, Y., Mukhamejanova, A., Muzyaev, E., Myktybekov, D., Nagorniy, S., Nassurlla, M., Nechaeva, P., Negodaev, M., Nesterov, V., Nevmerzhitsky, M., Nigmatkulov, G., Nikiforov, D., Nikitin, V., Nikolaev, A., Oleynik, D., Onuchin, V., Orlov, I., Orlova, A., Ososkov, G., Panzieri, D., Parsamyan, B., Pavzderin, P., Pavlov, V., Pedraza, M., Perelygin, V., Peshkov, D., Petrosyan, A., Petrov, M., Petrov, V., Petrukhin, K., Piskun, A., Pivovarov, S., Polishchuk, I., Polozov, P., Polyanskii, V., Ponomarev, A., Popov, V., Popovich, S., Prokhorova, D., Prokofiev, N., Prokoshin, F., Puchkov, A., Pudin, I., Pyata, E., Ratnikov, F., Rasin, V., Red'kov, V., Reshetin, A., Reznikov, S., Rogacheva, N., Romakhov, S., Rouba, A., Rudnev, V., Rusinov, V., Rusov, D., Ryltsov, V., Saduyev, N., Safonov, A., Sakhiyev, S., Salamatin, K., Saleev, V., Samartsev, A., Samigullin, E., Samoylov, O., Saprunov, E., Savenkov, A., Seleznev, A., Semak, A., Senkov, D., Sergeev, A., Seryogin, L., Seryubin, S., Shabanov, A., Shahinyan, A., Shavrin, A., Shein, I., Sheremeteva, A., Shevchenko, V., Shilyaev, K., Shimansky, S., Shinbulatov, S., Shipilov, F., Shipilova, A., Shkarovskiy, S., Shoukovy, D., Shpakov, K., Shreyber, I., Shtejer, K., Shulyakovsky, R., Shunko, A., Sinelshchikova, S., Skachkova, A., Skalnenkov, A., Smirnov, A., Smirnov, S., Snesarev, A., Solin, A., Solin jr., A., Soldatov, E., Solovtsov, V., Song, J., Sosnov, D., Stavinskiy, A., Stekacheva, D., Streletskaya, E., Strikhanov, M., Suarez, O., Sukhikh, A., Sukhovarov, S., Sulin, V., Sultanov, R., Sun, P., Svirida, D., Syresin, E., Tadevosyan, V., Tarasov, O., Tarkovsky, E., Tchekhovsky, V., Tcherniaev, E., Terekhin, A., Terkulov, A., Tereshchenko, V., Teryaev, O., Teterin, P., Tishevsky, A., Tokmenin, V., Topilin, N., Tsiareshka, P., Tumasyan, A., Tyumenkov, G., Usenko, E., Uvarov, L., Uzhinsky, V., Uzikov, Yu., Valiev, F., Vasilieva, E., Vasyukov, A., Vechernin, V., Verkheev, A., Vertogradov, L., Vertogradova, Yu., Vidal, R., Voitishin, N., Volkov, I., Volkov, P., Vorobyov, A., Voskanyan, H., Wang, H., Wang, Y., Xu, T., Yanovich, A., Yeletskikh, I., Yerezhep, N., Yurchenko, S., Zakharov, A., Zamiatin, N., Zamora-Saá, J., Zarochentsev, A., Zelenov, A., Zemlyanichkina, E., Zhabitsky, M., Zhang, J., Zhang, Zh., Zhemchugov, A., Zherebchevsky, V., Zhevlakov, A., Zhigareva, N., Zhou, J., Zhuang, X., Zhukov, I., Zhuravlev, N., Zinin, A., Zmeev, S., Zolotykh, D., Zubarev, E., and Zvyagina, A.

Subjects
High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

The Spin Physics Detector collaboration proposes to install a universal detector in the second interaction point of the NICA collider under construction (JINR, Dubna) to study the spin structure of the proton and deuteron and other spin-related phenomena using a unique possibility to operate with polarized proton and deuteron beams at a collision energy up to 27 GeV and a luminosity up to $10^{32}$ cm$^{-2}$ s$^{-1}$. As the main goal, the experiment aims to provide access to the gluon TMD PDFs in the proton and deuteron, as well as the gluon transversity distribution and tensor PDFs in the deuteron, via the measurement of specific single and double spin asymmetries using different complementary probes such as charmonia, open charm, and prompt photon production processes. Other polarized and unpolarized physics is possible, especially at the first stage of NICA operation with reduced luminosity and collision energy of the proton and ion beams. This document is dedicated exclusively to technical issues of the SPD setup construction.

Published
2024

6. High efficiency muon registration system based on scintillator strips

Author

Artikov, A., Baranov, V., Boikov, A., Chokheli, D., Davydov, Yu. I., Glagolev, V., Simonenko, A., Tsamalaidze, Z., Vasilyev, I., and Zimin, I.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

Experiments such as mu2e (FNAL, USA) and COMET (KEK, Japan), seeking the direct muon-to-electron conversion as part of the study of Charged Leptons Flavor Violation processes, should have a extremely high, up-to 99.99\%, efficiency muon detection system with a view to their subsequent suppression as background. In this article, the possibility to achieve such efficiency for a short and long term is discussed for modules based on 7- or 10-mm-thick but same 40-mm-wide plastic scintillation strips with single 1.2 mm WLS fiber glued into the groove along the strip and using MPPC/SiPM for light detection. A Simplified Light Yield Distribution method to estimate the efficiency of the module was proposed and the simulation results obtained with GEANT 4 for a system based on a 4-by-4 array of 7x40x3000 mm strips compared with the experimental data. Found that for the systems required the high level registration efficiency at the 99.99\% and more, it is important to improve the light yield as much as possible and achieve the gap between neighbor scintillation volumes as small as possible.

Published
2023

7. Direct coupling of nonlinear integrated cavities for all-optical reservoir computing

Author

Boikov, Ivan, Brunner, Daniel, and De Rossi, Alfredo

Subjects
Physics - Optics
Abstract

We consider theoretically a network of directly coupled optical microcavities to implement a space-multiplexed optical neural network in an integrated nanophotonic circuit. Nonlinear photonic network integrations based on direct coupling ensures a highly dense integration, reducing the chip footprint by several orders of magnitude compared to other implementations. Different nonlinear effects inherent to such microcavities are studied when used for realizing an all-optical autonomous computing substrate, here based on the reservoir computing concept. We provide an in-depth analysis of the impact of basic microcavity parameters on computational metrics of the system, namely, the dimensionality and the consistency. Importantly, we find that differences between frequencies and bandwidths of supermodes formed by the direct coupling is the determining factor of the reservoir's dimensionality and its scalability. The network's dimensionality can be improved with frequency-shifting nonlinear effects such as the Kerr effect, while two-photon absorption has an opposite effect. Finally, we demonstrate in simulation that the proposed reservoir is capable of solving the Mackey-Glass prediction and the optical signal recovery tasks at GHz timescale.

Published
2023

9. Evaluation of the Novelty of a Drive Based on a Structural Model

Author

Bushuev, A., Boikov, V., Bystrov, S., Nuyya, O., Sergeantova, M., Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Tan, Kay Chen, Series Editor, and S. Shmaliy, Yuriy, editor

Published
2024
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10. Thermal conductivity for p-(Bi, Sb)$_{2}$Te$_{3}$ films of topological insulators

Author

Lukyanova, L N, Boikov, Yu A, Usov, O A, Danilov, V A, Makarenko, I V, and Petrov, V N

Subjects
Condensed Matter - Materials Science
Abstract

The temperature dependences of the total, crystal lattice and electronic thermal conductivities were investigated in films of topological insulators p-Bi$_{0.5}$Sb$_{1.5}$Te$_{3}$ and p-Bi$_{2}$Te$_{3}$ formed by discrete and thermal evaporation methods. The largest decrease in the lattice thermal conductivity owing to the scattering of long-wavelength phonons on the grain interfaces was observed in the films of solid solutions p-Bi$_{0.5}$Sb$_{1.5}$Te$_{3}$ deposited by discrete evaporation on the amorphous substrates of polyimide without thermal treatment. It is shown that in the p-Bi$_{0.5}$Sb$_{1.5}$Te$_{3}$ films with low thermal conductivity the energy dependence of the relaxation time is enhanced, which is specific for the topological insulators. The electronic thermal conductivity was determined taking into account the effective scattering parameter in the relaxation time approximation versus energy in the Lorentz number calculations. The observed increase of the electronic thermal conductivity within the temperature range of 40 - 80 K is related to the weakening of the electrical conductivity temperature dependence and is determined by the increase in the effective scattering parameter at low temperatures due to the effect of scattering on the point antisite and impurity defects. A correlation was established between the thermal conductivity and features of the morphology of the interlayer surface (0001) in the studied films., Comment: 17 pages, 10 figures, 2 tables

Published
2022

11. SuperFGD prototype time resolution studies

Author

Alekseev, I., Arihara, T., Baranov, V., Bartoszek, L., Bernardi, L., Blondel, A., Boikov, A. V., Buizza-Avanzini, M., Cadoux, F., Capó, J., Cayo, J., Chakrani, J., Chong, P. S., Chvirova, A., Danilov, M., Davydov, Yu. I., Dergacheva, A., Dokania, N., Douqa, D., Drapier, O., Eguchi, A., Favre, Y., Fedorova, D., Fedotov, S., Fujii, Y., Gastaldi, F., Gendotti, A., Glagolev, V., Guillaumat, R., Iwamoto, K., Jakkapu, M., Jesús-Valls, C., Jung, C. K., Kakuno, H., Kasetti, S. P., Khabibullin, M., Khotjantsev, A., Kikutani, H., Kobayashi, T., Kodama, S., Korzenev, A., Kose, U., Kudenko, Y., Kutter, T., Last, D., Li, B., Li, Z., Lin, L. S., Lin, S., Louzir, M., Lux, T., Maret, L., Martynenko, S., Matsubara, T., Mauger, C., McGrew, C., Mefodiev, A., Mineev, O., Nakadaira, T., Nakagiri, K., Nanni, J., Nicola, L., Noah, E., Paolone, V., Parsa, S., Pellegrino, R., Ramirez, M. A., Reh, M., Ricco, C., Rubbia, A., Sakashita, K., Sanchez, F., Sgalaberna, D., Shvartsman, A., Skrobova, N., Suslov, I. A., Suvorov, S., Svirida, D., Teklu, A., Tereshchenko, V. V., Tzanov, M., Vasilyev, I. I., Wood, K., Yang, G., Yershov, N., Yokoyama, M., Yoshimoto, Y., Zhao, X., Zilberman, P., and Zimmerman, E. D.

Subjects
Physics - Instrumentation and Detectors
Abstract

The SuperFGD will be a part of the ND280 near detector of the T2K and Hyper Kamiokande projects, that will help to reduce systematic uncertainties related with neutrino flux and cross-section modeling. The upgraded ND280 will be able to perform a full exclusive reconstruction of the final state from neutrino-nucleus interactions, including measurements of low momentum protons, pions and, for the first time, event-by event measurements of neutron kinematics. The time resolution defines the neutron energy resolution. We present the results of time resolution measurements made with the SuperFGD prototype that consists of 9216 plastic scintillator cubes (cube size is 1 cm$^3$) readout with 1728 wavelength-shifting fibers going along three orthogonal directions. We use data from the muon beam exposure at CERN. The time resolution of 0.97 ns was obtained for one readout channel after implementing the time calibration with a correction for the time-walk effect. The time resolution improves with energy deposited in a scintillator cube. Averaging two readout channels for one scintillator cube improves the time resolution to 0.68 ns which means that signals in different channels are not synchronous. Therefore the contribution from the time recording step of 2.5 ns is averaged as well. Averaging time values from N channels improves the time resolution by $\sim 1/\sqrt{N}$. Therefore a very good time resolution should be achievable for neutrons since neutron recoils hit typically several scintillator cubes and in addition produce larger amplitudes than muons. Measurements performed with a laser and a wide-bandwidth oscilloscope demonstrated that the time resolution obtained with the muon beam is not far from its expected limit. The intrinsic time resolution of one channel is 0.67 ns for signals of 56 photo-electron typical for minimum ionizing particles., Comment: 12 pages, 9 figures. Revised text, results unchanged

Published
2022
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12. A photonics perspective on computing with physical substrates

Author

Abreu, S., Boikov, I., Goldmann, M., Jonuzi, T., Lupo, A., Masaad, S., Nguyen, L., Picco, E., Pourcel, G., Skalli, A., Talandier, L., Vettelschoss, B., Vlieg, E.A., Argyris, A., Bienstman, P., Brunner, D., Dambre, J., Daudet, L., Domenech, J.D., Fischer, I., Horst, F., Massar, S., Mirasso, C.R., Offrein, B.J., Rossi, A., Soriano, M.C., Sygletos, S., and Turitsyn, S.K.

Published
2024
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13. Digital technologies for signal radio vision and radio monitoring

Author

M. S. Kostin and K. A. Boikov

Subjects
signal radiovision, radiogenome, radio image, physically unclonable function, cumulant, pole-genetic functions, Information theory, Q350-390
Abstract

Objectives. Radiophysical processes involving the electrodynamic formation of signal radio images diffusely scattered by the signature of small-sized objects or induced by the near field of radio devices are relevant for identifying radiogenomic (cumulant) features of objects in the microwave range in the development of neuroimaging ultra-short pulse (USP) signal radio vision systems, telemonitoring, and near-radio detection. The paper sets out to develop methods and algorithms for vector analysis of radio wave deformation of nonstationary fields forming a signal radio image based on radiophysical and topological characteristics of small-sized objects; to develop software and hardware for registration and neural network recognition of signal radio images, including methods for the synthesis and extraction of signal radiogenomes using digital twins of objects obtained through vector electrodynamic modeling; and to analyze signal radio images induced by elements of printed topology of electronic devices.Methods. The study is based on statistical radiophysics methods, time-frequency approaches for wavelet transformation of USP radio images, numerical electrodynamic methods for creating digital twins of small-sized objects, as well as neural network authentication algorithms based on the cumulant theory of pole-genetic and resonant physically unclonable functions used in identifying signal radio images.Results. The results of fundamental research on electrodynamic effects of vector-wave deformation of nonstationary fields of sub-nanosecond configuration are presented as a means of identifying and authenticating signal radio images. Neural network techniques for cumulant formation of radio genomes of signal radio images are proposed on the basis of pole-genetic and resonant functions.Conclusions. A radiogenome, representing the unique authenticator of a radio image, is shown to be formed on the basis of physically unclonable functions determined by the structure and set of radiophysical parameters of the image. Cumulant features of signal radio images identified on the basis of pole-genetic and physically unclonable resonant functions of small-sized objects are revealed.

Published
2024
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14. Selective inhibitor of sodium-calcium exchanger, SEA0400, affects NMDA receptor currents and abolishes their calcium-dependent block by tricyclic antidepressants

Author

Sergei I. Boikov, Tatiana V. Karelina, Dmitry A. Sibarov, and Sergei M. Antonov

Subjects
NMDA receptor, sodium-calcium exchanger, SEA0400, amitriptyline, desipramine, clomipramine, Therapeutics. Pharmacology, RM1-950
Abstract

The open-channel block of N-methyl-D-aspartate receptors (NMDARs) and their calcium-dependent desensitization (CDD) represent conventional mechanisms of glutamatergic synapse regulation. In neurotrauma, neurodegeneration, and neuropathic pain the clinical benefits of cure with memantine, ketamine, Mg2+, and some tricyclic antidepressants are often attributed to NMDAR open-channel block, while possible involvement of NMDAR CDD in the therapy is not well established. Here the effects of selective high-affinity sodium-calcium exchanger (NCX) isoform 1 inhibitor, SEA0400, on NMDA-activated whole-cell currents and their block by amitriptyline, desipramine and clomipramine recorded by patch-clamp technique in cortical neurons of primary culture were studied. We demonstrated that in the presence of extracellular Ca2+, 50 nM SEA0400 caused a reversible decrease of the steady-state amplitude of NMDAR currents, whereas loading neurons with BAPTA or the removal of extracellular Ca2+ abolished the effect. The decrease did not exceed 30% of the amplitude and did not depend on membrane voltage. The external Mg2+ block and 50 nM SEA0400 inhibition of currents were additive, suggesting their independent modes of action. In the presence of Ca2+ SEA0400 speeded up the decay of NMDAR currents to the steady state determined by CDD. The measured IC50 value of 27 nM for SEA0400-induced inhibition coincides with that for NCX1. Presumably, SEA0400 effects are induced by an enhancement of NMDAR CDD through the inhibition of Ca2+ extrusion by NCX1. SEA0400, in addition, at nanomolar concentrations could interfere with Ca2+-dependent effect of tricyclic antidepressants. In the presence of 50 nM SEA0400, the IC50s for NMDAR inhibition by amitriptyline and desipramine increased by about 20 folds, as the Ca2+-dependent NMDAR inhibition disappeared. This observation highlights NCX1 involvement in amitriptyline and desipramine effects on NMDARs and unmasks competitive relationships between SEA0400 and these antidepressants. Neither amitriptyline nor desipramine could affect NCX3. The open-channel block of NMDARs by these substances was not affected by SEA0400. In agreement, SEA0400 did not change the IC50 for clomipramine, which acts as a pure NMDAR open-channel blocker. Thus, NCX seems to represent a promising molecular target to treat neurological disorders, because of the ability to modulate NMDARs by decreasing the open probability through the enhancement of their CDD.

Published
2024
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15. Software-architectural configuration of the multifunctional audio digital signal processor module for signal mediatesting of audio devices

Author

A. V. Gevorsky, M. S. Kostin, and K. A. Boikov

Subjects
audio module, adsp, adau1701, visual-graphic programming, software-defined architecture, audio-visual signal processing, audio signal, media-testing, Information theory, Q350-390
Abstract

Objectives. The aim of this study is to develop and analyze parameters for a multifunctional audio module based on the ADAU1701 audio digital signal processor in the SigmaStudio environment. This will be used for testing audio devices in the following modes: routing of balanced and unbalanced audio channels according to the differential scheme Di-Box/R Di-Box; spatiotemporal and dynamic audio processing; three-band monochannel cross-separation with independent equalization; and correction of the frequency response of the audio channel with tracking notch auto-suppression of electro-acoustic positive feedback in a given spectral band.Methods. Visual-graphical architectural programming of audio modules in the SigmaStudio and Flowstone, as well as algorithms for real-time signal audio measurements and analysis of experimental data in the REW and Soundcard Oscilloscope are used.Results. The characteristics of the Di-Box/R Di-Box circuit were studied, in order to estimate the effect of differential signal conversion on the signal-to-noise ratio in the audio signal path. The characteristics of the reverberation and saturation submodules were established. Furthermore, the effect of equalization modes on the frequency response correction of a studio audio monitor was determined. The paper also studied the effect of an audio compressor on the dynamic range and the level of the output signal. The experimental results of the submodule for compensating the frequency response of an audio monitor using matched filtering were established, and the spectral characteristics of the submodule for automatic suppression of electro-acoustic positive feedback were obtained.Conclusions. The software architecture of a multifunctional audio module based on the ADAU1701 audio digital signal processor for testing and debugging media devices in a given spectral-dynamic and spectral-temporal ranges was designed. Balanced routing allows the effect of noise induced into the audio channel to be reduced 20-fold, thus enabling calibration of pickup audio devices. The audio signal processing submodule provides: compression response in the dynamic range from −27 to 18.6 dB with the possibility of equalization parameterization in the range of 0.04–18 kHz; reverberation response in the range from 0.5–3000 ms; audio-channel cross-division into 3 with the ability to adjust the amplitude-frequency response in the dynamic range from −30 to 30 dB. The auto-correction submodule of the amplitude-frequency response allows the dynamic nonuniformity of the amplitude-frequency response to be reduced by 40 dB. The auto-suppression submodule of electro-acoustic positive feedback provides notch formant suppression up to −100 dB with an input dynamic range from −50 to 80 dB.

Published
2024
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18. Electronic structure and composition of tin oxide thin epitaxial and magnetron layers according to synchrotron XANES studies

Author

Olga A. Chuvenkova, Nikolai I. Boikov, Stanislav V. Ryabtsev, Elena V. Parinova, Ratibor G. Chumakov, Alexei M. Lebedev, Dmitry Smirnov, Anna Makarova, Sofiia S. Titova, Kirill A. Fateev, and Sergey Yu. Turishchev

Subjects
tin and its oxides, electronic structure, density of states, local atomic surrounding, composition, epitaxial nanolayers, x-ray absorption near edge structure, synchrotron investigations, magnetron nanolayers, Chemistry, QD1-999
Abstract

The materials of the tin-oxygen system and thin-film structures based on them are modern and actual for the creation of a wide range of electronic devices, for example, resistive gas sensors of high sensitivity and short response time with low energy consumption and high manufacturability. An important direction in the study of such materials and structures is the control of properties with variations in technological formation regimes. Information on the composition, local atomic and electronic structure of thin layers of the tin-oxygen system with varying approaches to their production is in demand. The work is devoted to the study of the electronic structure of thin layers of tin oxides obtained by modern methods of molecular beam epitaxy and magnetron sputtering. A study of the local partial density of electronic states in the conduction band by X-ray absorption near edge structure spectroscopy of tin and oxygen has been carried out. The data were obtained using high-intensity synchrotron radiation, which allows varying the monochromatized radiation quantum energy without loss in intensity, that is necessary to obtain high-resolution X-ray spectral data. It is shown that the composition, local atomic surrounding, electronic spectrum and their features depend on the technology of formation and storage conditions of the studied structures. Synchrotron X-ray spectroscopy data show the presence of intermediate oxides of the tin-oxygen system in the studied materials after prolonged storage in laboratory conditions. The data obtained indicate the possibility of controlled variation in the composition, local atomic surrounding and electronic spectrum of thin-film structures of tin oxides of small thickness. The results of the work can be used in the formation and subsequent modification of thin and ultrathin layers of tin oxides by magnetron sputtering and molecular beam epitaxy, as well as in their further application as active layers of microelectronics devices

Published
2024
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19. Study of Sustainability and Manageability of Economic Objects of the Cooperative Sector

Author

Katanaev, Nikolai T., Volkova, Natalia A., Panteleeva, Tatyana A., Koroleva, Liudmila L., Boikov, Aleksanr I., Pisello, Anna Laura, Editorial Board Member, Hawkes, Dean, Editorial Board Member, Bougdah, Hocine, Editorial Board Member, Rosso, Federica, Editorial Board Member, Abdalla, Hassan, Editorial Board Member, Boemi, Sofia-Natalia, Editorial Board Member, Mohareb, Nabil, Editorial Board Member, Mesbah Elkaffas, Saleh, Editorial Board Member, Bozonnet, Emmanuel, Editorial Board Member, Pignatta, Gloria, Editorial Board Member, Mahgoub, Yasser, Editorial Board Member, De Bonis, Luciano, Editorial Board Member, Kostopoulou, Stella, Editorial Board Member, Pradhan, Biswajeet, Editorial Board Member, Abdul Mannan, Md., Editorial Board Member, Alalouch, Chaham, Editorial Board Member, O. Gawad, Iman, Editorial Board Member, Nayyar, Anand, Editorial Board Member, Amer, Mourad, Series Editor, Buchaev, Yakhya G., editor, Abdulkadyrov, Arsen S., editor, Ragulina, Julia V., editor, Khachaturyan, Arutyun A., editor, and Popkova, Elena G., editor

Published
2023
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20. Study of a New Method of Radio-Sensor Identification of Radio-Electronic Devices

Author

K. А. Boikov

Subjects
identification, authentication, signal radio profile, pearson's criterion, radio electronic unit, correlation analysis, Telecommunication, TK5101-6720
Abstract

The purpose of this work is to increase the protection of radio-electronic devices from illegal cloning, by studying a new physically unclonable functions (PUF) connected with the own electromagnetic radiation of a radio-electronic device. The work uses experimental research methods to record the electrical component of the electromagnetic field emitted by the product - the signal radio profile (SRP). Correlation analysis methods for product authentication, Pearson's statistical agreement method for identification are used. The practical significance of the work lies in the possibility of using the SRP to identify a group of devices and radio-technical protection of a radio-electronic product from fakes and illegal copies.

Published
2023
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22. THEORETICAL STUDIES OF DRILLING FROZEN SOILS WITH A SCREW DRILL

Author

Igor G. Martyuchenko, Maxim I. Zenin, Alexey Yu. Kolesnikov, and Evgeny V. Boikov

Subjects
Well drilling, frozen soils, screw drill, soil destruction, well formation, drilling tools, Engineering geology. Rock mechanics. Soil mechanics. Underground construction, TA703-712
Abstract

Link for citation: Martyuchenko I.G., Zenin M.I., Kolesnikov A.Yu., Boikov E.V. Theoretical studies of drilling frozen soils with a screw drill. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 9, рр. 194-202. In Rus. The relevance of the study is caused by the need to create a new drilling tool to drill frozen soil in difficult conditions. This line of research is important and relevant for ensuring the formation of wells on frozen sands, since the screw drilling tool performs the deformation of frozen soil separation, which makes it possible to drill hard-to-drill soils, namely frozen sands. The main aim: to study the interaction of the destructive part of the helical drill with frozen soil and determine the rational values of the geometric parameters of the helical blade when achieving the lowest value of the force of soil separation and the highest value of the productivity of drilling. Objects: interaction of the destructive part of the helical blade of a helical drill with frozen soil. Methods: plotting dependencies of factors showing the energy intensity of drilling, on the angle of rotation of the radius of the helical blade, at which it increments, and on the pitch of the helical blade in the second section of the destructive part of the helical drill; analysis of the obtained results of theoretical studies of the force of soil separation and the efficiency of drilling from the geometric parameters of the helical blade of a drilling tool on frozen soils. Results. The authors have studied the influence of the geometrical parameters of the helical drill on well formation, obtained the dependences of the efforts and constructed the graphs for soil separation, as well as the dependence of the productivity of drilling on the angle of rotation of the radius of the helical blade, at which it increments, and on the pitch of the helical blade in the second section of the destructive part of the helical drill. Based on the results of theoretical studies, an analysis of the obtained dependencies was carried out and the area of rational values of the geometric parameters of the helical blade of a helical drill on frozen soils was found.

Published
2023
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25. Secretory phospholipase A2: a biomarker of inflammation in autoimmune, bacterial and viral diseases

Author

S. P. Urazov, A. N. Chernov, A. V. Cherkas, A. V. Boikov, O. S. Glotov, S. V. Apalko, N. N. Sushentseva, I. A. Polkovnikova, V. V. Smirnov, and S. G. Shcherbak

Subjects
secretory phospholipase a2, isoforms, mechanisms of action, diagnostic significance, prognostic value, inflammation, cardiovascular diseases, bacterial diseases, viral diseases, autoimmune diseases, correlations, Immunologic diseases. Allergy, RC581-607
Abstract

Secretory phospholipases A2 (sPLA2) represent a large superfamily of enzymes with a molecular weight of 14-19 kDa, including 15 groups and more than 30 isoforms belonging to four types: secretory (sPLA2), cytosolic (cPLA2), calcium-independent (iPLA2) and lipoprotein-associated phospholipase A2 (LP-PLA2, PAF-AH). Eleven species of secretory sPLA2s (IB, IIA, IIC, IID, IIE, IIF, III, V, X, XIIA, and XIIB) have been found in mammals, performing versatile functions and participating in the pathogenesis of a wide range of diseases. On the one hand, sPLA2 may promote elimination of damaged, apoptotic cells by hydrolyzing membrane phospholipids, and exerts a strong bactericidal and antiviral properties, including pronounced effects against antibiotic-resistant strains of microorganisms. In this regard, the use of sPLA2 may represent a new strategy for the treatment of bacterial and viral infections. Moreover, due to the action of sPLA2 on its substrates, a number of biologically active molecules (arachidonic, lysophosphatidic acids, lysophospholipids, fatty acids, prostaglandins, leukotrienes, thromboxanes) are formed, which provide strong inflammatory, detergent, coagulating effects and increase vascular permeability. This pro-inflammatory role of sPLA2 may explain its increase levels and activity in cardiovascular, respiratory, autoimmune, metabolic, oncological, bacterial and viral disorders. The review article presents a classification of sPLA2 isoforms, their substrates, regulatory factors, biological significance, and mechanisms of their strong bactericidal, virucidal, and pro-inflammatory activity in the heart and lung disorders, autoimmune, metabolic, bacterial, and viral diseases. In particular, the mechanisms of the selective action of sPLA2 against Gram-positive and Gram-negative microorganisms are discussed. We consider diagnostic and prognostic significance, correlations between elevated levels and activity of sPLA2 and distinct clinical symptoms, severity and outcome in the patients with coronary heart disease (CAD), acute myocardial infarction (AMI), atherosclerosis, acute inflammatory lung injury (ALI), respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, bronchial asthma, bacterial infections, septicemia and viral (COVID-19) infections. The opportunity of using sPLA2 as a biomarker of the severity and outcome of patients with chronic obstructive pulmonary disease, bacterial infections, sepsis and viral infections, including COVID-19, is also considered.

Published
2022
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29. Determination of Parameters of Electronic Devices by the Method of Passive Radio-Sensor Technical Diagnostics

Author

K. A. Boikov

Subjects
technical diagnostics, signal radio profile, free oscillations, decay time, radiation superposition, Electronics, TK7800-8360
Abstract

Introduction. Technical diagnostics (TD) as a nascent discipline is rapidly developing in the field of both software and hardware. Modern TD methods, such as vibrometry, thermal control, JTAG testing and optical control, either exhibit high inertia, consume processor time, require suspension of the electronic device, or demand a galvanic contact with the study object, which is often unacceptable. These disadvantages can be eliminated by passive radio-sensor TD. To date, little information has been published on the parameters of electronic devices provided by this method.Aim. Determination of the parameters of electronic devices, the assessment of which can be provided by passive radio-sensor TD.Materials and methods. Signal radio profiles were obtained experimentally using metrological equipment and software-numerical methods for modeling radio wave processes. The parameters of the signal radio profile were calculated by a mathematical method for solving differential equations.Results. The main principles and results of radio-sensor TD, as well as the simplest toolkit, are shown. An equation is obtained for the signal radio profile emitted by the electronic unit of the device, as well as an expression for its free components. An approach for assessing the TD correctness based on the number of free components of the received signal radio profile and the reference is described. The possibility of obtaining information about temperature, voltage drop, speed of emitting nodes, as well as the state of its components and modes of operation of p–njunctions is demonstrated. It is shown that this information is carried by the parameters of the basic equation for the signal radio profile.Conclusion. The derived basic equation allows a non-contact, remote passive radio-sensor TD to be conducted by correlation analysis of the received signal, providing a detailed examination of malfunctions in each electronic unit. The described TD method based on the presented parameters is promising for assessing the technical state of electronic devices.

Published
2021
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31. Radiosensory diagnostics of signal integrity in-circuit and peripheral architecture of microprocessor devices

Author

K. A. Boikov, M. S. Kostin, and G. V. Kulikov

Subjects
technical diagnostics, radio sensor scanning, signal radio profile, microprocessor device, in-circuit architecture, peripheral architecture, signal integrity, electromagnetic radiation, free oscillations, Information theory, Q350-390
Abstract

For the first time, a passive method for radiosensor diagnostics of the integrity of signals from microprocessor devices was developed and presented. The method is based on the registration of the electrical component of the near field of electromagnetic radiation induced as a result of the clock formation (variability) of the impulse response of a digital circuit caused by the dynamic restructuring of the active configuration of its in-circuit and peripheral architecture. It is shown that real radiation is a superposition of fields of emitters of the active architecture of a microprocessor, each of which has its own impulse and amplitude-frequency characteristics with its own peaks and dips, resonances and excitations. An expression of the free component is presented for the oscillatory nature of the process of energy redistribution between reactive storage devices, which depends on the capacitances of the gate dielectrics of MIS transistors, barrier and diffusion capacities of p-n junctions, inductances and ohmic resistances of circuit elements and the scheme of their architectural connection. An experiment was prepared and carried out on the method of passive radio-wave technical diagnostics of microprocessor devices on a specially developed test sample with a known command execution algorithm. The results of registration of a series of signal radio profiles when starting a sample of a digital device are presented, and a correlation assessment of the reproducibility of the experiment is carried out. It is proved that time interval transitions of free oscillations are formed on the reference signal radio profile. These transitions correspond to the microcontroller’s reference to the periphery according to the algorithm of the command functioning of the sample. The possibility of obtaining detailed information about the nature of the peripheral load and its performance by examining the corresponding sections of the reference signal radio profile is shown. It was found that the spectral-time frames of the software and hardware functioning of the digital device under study are clearly identified on the recorded radio images.

Published
2021
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32. Unveiling the Role of Cholesterol in Subnanomolar Ouabain Rescue of Cortical Neurons from Calcium Overload Caused by Excitotoxic Insults

Author

Dmitry A. Sibarov, Zoia D. Zhuravleva, Margarita A. Ilina, Sergei I. Boikov, Yulia D. Stepanenko, Tatiana V. Karelina, and Sergei M. Antonov

Subjects
NMDA receptor, neurons, Na/K-ATPase, cholesterol, calcium, Na/Ca exchanger, Cytology, QH573-671
Abstract

Na/K-ATPase maintains transmembrane ionic gradients and acts as a signal transducer when bound to endogenous cardiotonic steroids. At subnanomolar concentrations, ouabain induces neuroprotection against calcium overload and apoptosis of neurons during excitotoxic stress. Here, the role of lipid rafts in interactions between Na/K-ATPase, sodium–calcium exchanger (NCX), and N-methy-D-aspartate receptors (NMDARs) was investigated. We analyzed 0.5–1-nanometer ouabain’s effects on calcium responses and miniature post-synaptic current (mEPSCs) frequencies of cortical neurons during the action of NMDA in rat primary culture and brain slices. In both objects, ouabain attenuated NMDA-evoked calcium responses and prevented an increase in mEPSC frequency, while the cholesterol extraction by methyl-β-cyclodextrin prevented the effects. The data support the conclusions that (i) ouabain-induced inhibition of NMDA-elicited calcium response involves both pre- and post-synapse, (ii) the presence of astrocytes in the tripartite synapse is not critical for the ouabain effects, which are found to be similar in cell cultures and brain slices, and (iii) ouabain action requires the integrity of cholesterol-rich membrane microdomains in which the colocalization and functional interaction of NMDAR-transferred calcium influx, calcium extrusion by NCX, and Na/K-ATPase modulation of the exchanger occur. This regulation of the molecules by cardiotonic steroids may influence synaptic transmission, prevent excitotoxic neuronal death, and interfere with the pharmacological actions of neurological medicines.

Published
2023
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37. Automated digitization of radial charts

Author

Nataliya V. Vasilyeva, Aleksei V. Boikov, Olga O. Erokhina, and Andrei Yu. Trifonov

Subjects
image digitization, radial charts, labview, image identification, digital image processing, automation, Mining engineering. Metallurgy, TN1-997
Abstract

Radial charts were commonly used in the industry to allow retrospective assessment of technological parameters. Today it is relevant to digitize the obtained data in order to simplify the automation of technological processes. Digitization of radial charts by means of standard methods is carried out with the help of human labor at significant time costs. The article proposes an automated method for digitizing radial charts using software, developed in the LabVIEW programming environment. The results of processing radial charts are displayed on the screen in numerical and graphical form, and can also be exported to a file (for example, to Notepad or MS Excel). The presented technique can be applied to images obtained on a color or black-and-white scanner, which minimizes geometric distortions, associated with the conversion of a paper document into electronic form, and ensures recognition quality of the clear plot line with an average relative error of up to 3 %. In case of ink fading or perspective photos of the diagram, the value of relative error can reach 8 %, as a result of which additional manual correction of the data will be required.

Published
2021
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38. Nutritional and Metabolic Factors, Ethanol and Cholesterol, Interact With Calcium-Dependent N-Methyl-D-Aspartate Receptor Inhibition by Tricyclic Antidepressants

Author

Sergei I. Boikov, Dmitry A. Sibarov, and Sergei M. Antonov

Subjects
NMDA receptors, tricyclic antidepressants, amitriptyline, desipramine, clomipramine, ethanol, Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571
Abstract

It is known that overexpression of N-methyl-D-aspartate receptors (NMDARs) contributes to central sensitization and development of neuropathic pain. Tricyclic antidepressants (TCAs), amitriptyline (ATL), and desipramine (DES) exhibit analgetic anti-NMDAR activity and are commonly utilized for pain therapy. This property is determined by their ability to enhance the calcium-dependent desensitization (CDD) of NMDARs. Coincidently ethanol and cholesterol, the ubiquitous food supplements, also modulate NMDAR CDD. The convergence of the effects of these compounds on a similar calcium-dependent process allows to assume their interaction on NMDARs. Since there is no information on whether ethanol supplementation and cholesterol deficit interfere with TCA inhibition of NMDARs at a cellular level, here we investigated this issue. Whole-cell NMDA-activated currents were recorded in rat cortical neurons of primary cultures to study how the IC50 values for TCA inhibition of NMDARs are influenced by ethanol and cholesterol extraction from the plasma membrane with methyl-β-cyclodextrin. Ethanol at 0.03% did not reliably affect the steady-state NMDA-activated currents. At this threshold concentration ethanol, however, increased IC50s for ATL and DES abolishing their calcium-dependent inhibition of NMDARs but did not change IC50 for clomipramine (CLO), which is calcium-independent. Whereas the ethanol effects on ATL-induced NMDAR inhibition reached a maximum at 2 mM external [Ca2+], for DES the maximum was achieved already at 1 mM external [Ca2+], that correlates with the manifestation of the calcium-dependent inhibition of NMDARs by these agents. Cholesterol depletion also increased IC50s for both ATL and DES abolishing the calcium-dependent inhibition of NMDARs. The restitution of cholesterol in the plasma membrane reversed the ATL IC50 back to the low values, by a restoration of calcium-dependence of ATL. These observations are consistent with the explanation that either 0.03% ethanol or cholesterol extraction may interrupt some intermediate step of CDD transduction or augment NMDAR CDD to the maximal level so that ATL and DES could not further enhance CDD. It is likely that anti-NMDAR action of ATL and DES against neuropathic pain could demonstrate peculiarities in therapeutic profiles during cholesterol decline in aging or medical treatments and ethanol supplementations even in quantities that are insufficient to cause the symptoms of intoxication.

Published
2022
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43. Quantum oscillations of magnetoresistance of the submicrometer thick bismuth telluride-based films

Author

Lukyanova, L. N., Boikov, Yu. A., Danilov, V. A., Usov, O. A., Volkov, M. P., and Kutasov, V. A.

Subjects
Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

Hetero-epitaxial films based on bismuth telluride with excess of Te were grown by hat wall technique at the surface of the mica (muscovite). Galvanomagnetic properties of the thin films were measured, and quantum oscillations of the magnetoresistance were found at the temperatures below 10 K in the magnetic field from 6 to 14 T. From analysis of magnetoresistance oscillations the main surface state parameters of the films were determined. Expementally obtained Landau level index shift and its temperature dependence are consistent with Berry phase specific for topological Dirac surface states. The estimated parameters of electronic topological surface states of the bismuth telluride-based films are of special interest because of possible usage of them in micro generators and micro coolers, and also for other device applications., Comment: 5 pages, 5 figures

Published
2014

44. Thermoelectric and galvanomagnetic properties of bismuth chalcogenide nanostructured hetero-epitaxial films

Author

Lukyanova, L. N., Boikov, Yu. A., Danilov, V A, Usov, O A, Volkov, M P, and Kutasov, V. A.

Subjects
Condensed Matter - Materials Science
Abstract

Hot wall technique was used to grow block single crystal films of Bi_2Te_3 and solid solutions of Bi_(0.5)Sb_(1.5)Te_3 on mica (muscovite) substrates. X-ray diffraction studies demonstrated that the crystalline c-axis in the films was normal to the substrate plane. Seebeck coefficient, electrical conductivity and magnetoresistivity tensor components were measured at various orientations of magnetic and electric fields in the temperature interval 77-300 K and magnetic field up to 14 T. Scattering mechanism of charge carriers in the films were studied using temperature dependences of the degeneracy parameter and the Seebeck coefficient in terms of a many-valley model of energy spectrum. Obtained results have shown that the effective scattering parameter is considerably differed from the value specific for an acoustic scattering of charge carriers in the weakly degenerate films due to an additional scattering of charge carriers on interface and interctystallite boundaries. These features of charge carrier scattering are supposed to affect electronic transport in the films and enhance figure of merit., Comment: 10 pages, 10 figures

Published
2014
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45. Automated Tire Pressure Control System for Multi-Purpose Wheeled Vehicles

Author

V. P. Boikov, V. V. Guskov, and A. S. Pavarekha

Subjects
automatic regulation, tire, air pressure, propulsion, traction and coupling properties, Technology
Abstract

The cross-country capability of multi-purpose wheeled vehicles is one of the most important operational properties of these technical objects. In many ways, it is determined by their traction characteristics. There are a number of ways to improve traction and coupling properties of multipurpose wheeled vehicles, the main ones are the use of various kinds of traction control systems, blocking of interaxle and interwheel differentials, the use of ballast and several others. Recently, one of the ways to improve the traction properties and cross-country ability of vehicles on soils with weak load-bearing capacity is a regulation of air pressure in the tires of the driving wheels of multi-purpose wheeled vehicles. The paper describes the process of interaction of the wheel mover with the ground surface when the air pressure in the tire changes. The influence of air pressure on the traction properties of wheeled vehicles is established. The system of automatic control of air pressure in tires of mobile cars depending on road conditions is offered. The use of the proposed regulation principle will significantly increase the cross-country ability of multi-purpose wheeled vehicles in heavy traffic conditions, eliminating the subjective factor in the person of the vehicle operator.

Published
2021
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46. Thermal Conductivity for p–(Bi, Sb)2Te3 Films of Topological Insulators

Author

Lidia N. Lukyanova, Yuri A. Boikov, Oleg A. Usov, Viacheslav A. Danilov, Igor V. Makarenko, and Vasilii N. Petrov

Subjects
bismuth telluride, solid solutions, films, thermal conductivity, scattering parameter, topological insulator, Chemistry, QD1-999
Abstract

In this study, we investigated the temperature dependencies of the total, crystal lattice, and electronic thermal conductivities in films of topological insulators p–Bi0.5Sb1.5Te3 and p–Bi2Te3 formed by discrete and thermal evaporation methods. The largest decrease in the lattice thermal conductivity because of the scattering of long-wavelength phonons on the grain interfaces was observed in the films of the solid-solution p–Bi0.5Sb1.5Te3 deposited by discrete evaporation on the amorphous substrates of polyimide without thermal treatment. It was shown that in the p–Bi0.5Sb1.5Te3 films with low thermal conductivity, the energy dependence of the relaxation time is enhanced, which is specific to the topological insulators. The electronic thermal conductivity was determined by taking into account the effective scattering parameter in the relaxation time approximation versus energy in the Lorentz number calculations. A correlation was established between the thermal conductivity and the peculiarities of the morphology of the interlayer surface (0001) in the studied films. Additionally, the total κ and the lattice κL thermal conductivities decrease, while the number of grains and the roughness of the surface (0001) increase in unannealed films compared to annealed ones. It was demonstrated that increasing the thermoelectric figure of merit ZT in the p–Bi0.5Sb1.5Te3 films formed by discrete evaporation on a polyimide substrate is determined by an increase in the effective scattering parameter in topological insulators due to enhancement in the energy dependence of the relaxation time.

Published
2023
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49. Current induced mode competition in microdisk lasers

Author

Boikov, I. K., Savelyev, A. V., Breuer, S., Korenev, V. V., Kudryavcev, K. E., Kryzhanovskaya, N. V., Maximov, M. V., Zhukov, A. E., Boikov, I. K., Savelyev, A. V., Breuer, S., Korenev, V. V., Kudryavcev, K. E., Kryzhanovskaya, N. V., Maximov, M. V., and Zhukov, A. E.

Abstract

A phenomenon of mode competition in microdisk lasers under various injection currents was studied. The increase of the injection current causes rise of the internal temperature. The modeling has shown that this increase leads to the shift of the gain spectrum. That may be enough to cause drastic redistribution of emitted power between microdisk modes. This effect has been studied in the experiment and by the numerical simulation.

Published
2024

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