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N K Chemeris - One of the best experts on this subject based on the ideXlab platform.
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Pharmacological analysis of anti-inflammatory effects of low-intensity Extremely High-Frequency electromagnetic radiation
Biofizika, 2020Co-Authors: A B Gapeev, K V Lushnikov, Iu V Shumilina, N K ChemerisAbstract:The anti-inflammatory effect of low-intensity Extremely High-Frequency electromagnetic radiation (EHF EMR, 42.0 GHz, 0.1 mW/cm2) was compared with the action of the known anti-inflammatory drug sodium diclofenac and the antihistamine clemastine on acute inflammatory reaction in NMRI mice. The local inflammatory reaction was induced by intraplantar injection of zymosan into the left hind paw. Sodium diclofenac in doses of 2, 3, 5, 10, and 20 mg/kg or clemastine in doses of 0.02, 0.1, 0.2, 0.4, and 0.6 mg/kg were injected intraperitoneally 30 min after the initiation of inflammation. The animals were whole-body exposed to EHF EMR for 20 min at 1 h after the initiation of inflammation. The inflammatory reaction was assessed over 3 - 8 h after the initiation by measuring the footpad edema and hyperthermia of the inflamed paw. Sodium diclofenac in doses of 5 - 20 mg/kg reduced the exudative edema on the average by 26% as compared to the control. Hyperthermia of the inflamed paw decreased to 60% as the dose of was increased diclofenac up to 20 mg/kg. EHF EMR reduced both the footpad edema and hyperthermia by about 20%, which was comparable with the effect of a single therapeutic dose of diclofenac (3 - 5 mg/kg). The combined action of diclofenac and the exposure to the EHF EMR caused a partial additive effect. Clemastine in doses of 0.02-0.4 mg/kg it did not cause any significant effects on the exudative edema, but in a dose of 0.6 mg/kg it reduced edema by 14 - 22% by 5 - 8 h after zymosan injection. Clemastine caused a dose-dependent increase in hyperthermia of inflamed paw at doses of 0.02-0.2 mg/kg and did not affect the hyperthermia at doses of 0.4 and 0.6 mg/kg. The combined action of clemastine and EHF EMR exposure caused a dose-dependent abolishment of the anti-inflammatory effect of EHF EMR. The results obtained suggest that both arachidonic acid metabolites and histamine are involved in the realization of anti-inflammatory effects of low-intensity
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changes in the chromatin structure of lymphoid cells under the influence of low intensity Extremely High Frequency electromagnetic radiation against the background of inflammatory process
Biophysics, 2011Co-Authors: A. B. Gapeyev, N. A. Romanova, N K ChemerisAbstract:Using the alkaline single cell gel electrophoresis technique (comet assay), changes in chromatin structure of peripheral blood leukocytes and peritoneal neutrophils have been studied in mice exposed to low-intensity Extremely High-Frequency electromagnetic radiation (42.2 GHz, 0.1 mW/cm2, 20 min at 1 h after induction of inflammation) against the background of the systemic inflammatory process. It was revealed that the exposure of mice with the developing inflammation leads to a pronounced decrease in the level of DNA damage to peripheral blood leukocytes and peritoneal neutrophils. It is supposed that the changes in the chromatin structure of lymphoid cells have a genoprotective character in the inflammatory process and can underlie the mechanisms of realization of antiinflammatory effects of the electromagnetic radiation.
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responses of thymocytes and splenocytes to low intensity Extremely High Frequency electromagnetic radiation in normal mice and in mice with systemic inflammation
Biophysics, 2010Co-Authors: A. B. Gapeyev, N P Sirota, A A Kudryavtsev, N K ChemerisAbstract:Changes in T cell subsets and expression of cytokine genes in thymocytes and splenocytes after exposure of BAL/c mice to low-intensity Extremely High-Frequency electromagnetic radiation (42.2 GHz, 0.1 mW/cm2, exposure duration 20 min) under normal conditions and in systemic inflammation were studied using flow cytometry and the methods of reverse transcription and real-time polymerase chain reaction. It was found that the number of CD4+ and CD8+ T cells statistically significantly increased in the thymus and considerably decreased in the spleen of exposed animals. Apparently, the exposure of animals leads to an intensification of the host defense, by activating the T-cellular immunity. As for effector functions, the increased expression of IL-1beta and IFNgamma genes in thymocytes and essentially enhanced expression of IL-1beta, IL-10, and TNFalpha genes in splenocytes were observed in mice exposed against the background of a progressive inflammatory process. The experimental data obtained specify that the directed (anti-inflammatory) response of an organism to a specific combination of effective exposure parameters of electromagnetic radiation can be realized by the activation of particular immunocompetent cells and changes in the cytokine profile.
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Responses of thymocytes and splenocytes to low-intensity Extremely High-Frequency electromagnetic radiation in normal mice and in mice with systemic inflammation
Biophysics, 2010Co-Authors: A. B. Gapeyev, A A Kudryavtsev, Sirota Np, N K ChemerisAbstract:Changes in T cell subsets and expression of cytokine genes in thymocytes and splenocytes after exposure of BALB/c mice to low-intensity Extremely High-Frequency electromagnetic radiation (42.2 GHz, 0.1 mW/cm2, exposure duration 20 min) under normal conditions and in systemic inflammation were studied using flow cytometry and the methods of reverse transcription and real-time polymerase chain reaction. It was found that the number of CD4+ and CD8+ T cells statistically significantly increased in the thymus and considerably decreased in the spleen of exposed animals. Apparently, the exposure of animals leads to an intensification of the host defense, by activating the T-cellular immunity. As for effector functions, the increased expression of IL-1β and IFNγ genes in thymocytes and essentially enhanced expression of IL-1β, IL-10, and TNFα genes in splenocytes were observed in mice exposed against the background of a progressive inflammatory process. The experimental data obtained specify that the directed (anti-inflammatory) response of an organism to a specific combination of effective exposure parameters of electromagnetic radiation can be realized by the activation of particular immunocompetent cells and changes in the cytokine profile.
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antitumor effect of low intensity Extremely High Frequency electromagnetic radiation on a model of solid ehrlich carcinoma
Biofizika, 2009Co-Authors: A B Gapeev, D M Shved, E N Mikhaĭlik, V V Shaposhnikova, V B Sadovnikov, A I Alekhin, N G Goncharov, N K ChemerisAbstract:The influence of different exposure regimes of low-intensity Extremely High-Frequency electromagnetic radiation on the growth rate of solid Ehrlich carcinoma in mice has been studied. It was shown that, at an optimum repetition factor of exposure (20 min daily for five consecutive days after the tumor inoculation), there is a clearly pronounced Frequency dependence of the antitumor effect. The analysis of experimental data indicates that the mechanisms of antitumor effects of the radiation may be related to the modification of the immune status of the organism. The results obtained show that Extremely High-Frequency electromagnetic radiation at a proper selection of exposure regimes can result in distinct and stable antitumor effects.
A. B. Gapeyev - One of the best experts on this subject based on the ideXlab platform.
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pulse modulated Extremely High Frequency electromagnetic radiation protects cellular dna from the damaging effects of physical and chemical factors in vitro
Biophysics, 2015Co-Authors: A. B. Gapeyev, N A LukyanovaAbstract:Using an alkaline version of the comet assay, we investigated the protective effects of Extremely High-Frequency electromagnetic radiation for DNA in mouse peripheral blood leukocytes on the damaging effects of X-ray radiation, hydrogen peroxide, and the alkylating agent methyl methanesulfonate. It was shown that the pre-exposure of cells to pulse-modulated low-intensity electromagnetic radiation (42.2 GHz, 100 µW/cm2, exposure for 20 min, and the modulation Frequency of 1 and 16 Hz) exerted a protective effect by reducing the level of DNA damage by 20–45% depending on the type of genotoxic agent. The effectiveness of pulse-modulated radiation increases in the following series: methyl methanesulfonate–X-rays–hydrogen peroxide. Continuous electromagnetic radiation does not have such a protective effect. The mechanisms of the detected protective effects may be associated with the induction of an adaptive response by reactive oxygen species that are formed by the action of pulse-modulated radiation in nanomolar concentrations.
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modifying effects of low intensity Extremely High Frequency electromagnetic radiation on content and composition of fatty acids in thymus of mice exposed to x rays
International Journal of Radiation Biology, 2015Co-Authors: A. B. Gapeyev, Alexander V Aripovsky, Tatiana P KulaginaAbstract:AbstractPurpose: The effects of Extremely High-Frequency electromagnetic radiation (EHF EMR) on thymus weight and its fatty acids (FA) content and FA composition in X-irradiated mice were studied to test the involvement of FA in possible protective effects of EHF EMR against ionizing radiation.Materials and methods: Mice were exposed to low-intensity pulse-modulated EHF EMR (42.2 GHz, 0.1 mW/cm2, 20 min exposure, 1 Hz modulation) and/or X-rays at a dose of 4 Gy with different sequences of the treatments. In 4–5 hours, 10, 30, and 40 days after the last exposure, the thymuses were weighed; total FA content and FA composition of the thymuses were determined on days 1, 10, and 30 using a gas chromatography.Results: It was shown that after X-irradiation of mice the total FA content per mg of thymic tissue was significantly increased in 4–5 h and decreased in 10 and 30 days after the treatment. On days 30 and 40 after X-irradiation, the thymus weight remained significantly reduced. The first and tenth days aft...
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Modifying effects of low-intensity Extremely High-Frequency electromagnetic radiation under injury induced by X-rays
2014 24th International Crimean Conference Microwave & Telecommunication Technology, 2014Co-Authors: A. B. Gapeyev, A. V. Aripovsky, T. P. KulaginaAbstract:It was shown for the first time that the exposure of laboratory SHK mice to low-intensity modulated Extremely High-Frequency electromagnetic radiation (EHF EMR) with effective parameters (carrier Frequency of 42.2 GHz, intensity of 0.1 mW/cm2, exposure duration for 20 min, pulse modulation with a Frequency of 1 Hz) before and after treatment with X-rays at a dose of 4 Gy caused pronounced radiation protective effect which is manifested as more recent restoration of thymus cellularity and a keeping unchanged summary content of fatty acids in thymic tissue. It is supposed that the mechanisms of the radiation protective effect of EHF EMR are connected with an induction of adaptive response and favorable action of the radiation on repair processes.
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exposure of tumor bearing mice to Extremely High Frequency electromagnetic radiation modifies the composition of fatty acids in thymocytes and tumor tissue
International Journal of Radiation Biology, 2013Co-Authors: A. B. Gapeyev, Tatiana P Kulagina, Alexander V AripovskyAbstract:AbstractPurpose: To test the participation of fatty acids (FA) in antitumor effects of Extremely High-Frequency electromagnetic radiation (EHF EMR), the changes in the FA composition in the thymus, liver, blood plasma, muscle tissue, and tumor tissue in mice with Ehrlich solid carcinoma exposed to EHF EMR were studied.Materials and methods: Normal and tumor-bearing mice were exposed to EHF EMR with effective parameters (42.2 GHz, 0.1 mW/cm2, 20 min daily during five consecutive days beginning the first day after the inoculation of tumor cells). Fatty acid composition of various organs and tissues of mice were determined using a gas chromatography.Results: It was shown that the exposure of normal mice to EHF EMR or tumor growth significantly increased the content of monounsaturated FA (MUFA) and decreased the content of polyunsaturated FA (PUFA) in all tissues examined. Exposure of tumor-bearing mice to EHF EMR led to the recovery of FA composition in thymocytes to the state that is typical for normal anim...
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Radiation protective action of low-intensity Extremely High-Frequency electromagnetic radiation
2012 22nd International Crimean Conference "Microwave & Telecommunication Technology", 2012Co-Authors: A. B. Gapeyev, N. A. RomanovaAbstract:It was shown for the first time that the exposure of mouse blood leukocytes to low-intensity modulated Extremely High-Frequency electromagnetic radiation (EHF EMR) with effective parameters (carrier Frequency of 42.2 GHz, intensity of 0.1 mW/cm2, exposure duration for 20 min, modulation Frequency of 1 Hz) before and after the treatment with X-rays in a dose of 5 Gy caused pronounced radiation protective effect which is manifested as a decrease in DNA damage. It is supposed that the mechanisms of the radiation protective effect are connected with an induction of adaptive response by reactive oxygen species.
Richard B. True - One of the best experts on this subject based on the ideXlab platform.
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a compact Extremely High Frequency mpm power amplifier
IEEE Transactions on Electron Devices, 2018Co-Authors: Carter M. Armstrong, Richard Kowalczyk, Andrew Zubyk, Kevin Berg, Clark Meadows, Danny Chan, Thomas Schoemehl, Ramon Duggal, Nora Hinch, Richard B. TrueAbstract:The development of a compact radio Frequency (RF) vacuum power amplifier for High-resolution airborne radar is described. The amplifier, a microwave power module (MPM), operates in the upper millimeter-wave Frequency band of 231.5–235 GHz providing a peak output power of 32 W. Common with previous Extremely High Frequency MPM development at Electron Devices, the ${G}$ -band MPM consists of a periodic permanent magnet focused serpentine waveguide traveling wave tube (TWT) and a miniaturized 20-kV electronic power conditioner. Input drive to the MPM for saturation is around 10 mW. Low-loss chemical vapor deposition diamond WR-4.3 windows serve as the input and output ports of the TWT. Due to the High duty of the radar application, a four-stage TWT collector is employed for beam energy recovery. The MPM operates from a 270- $\text{V}_{\sf {dc}}$ power source. Two MPM configurations have been constructed: a single integrated unit for laboratory testing and a split-package configuration for integration in a standard electro-optical/infrared gimbal. The split-package flight test unit has a maximum prime power requirement of 176 W, corresponding to an overall amplifier efficiency of 9%. The radar sensor has been flown on a modified DC-3 test bed with High-resolution real-time video imagery obtained under cloud-obscured operating conditions.
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A Compact Extremely High Frequency MPM Power Amplifier
IEEE Transactions on Electron Devices, 2018Co-Authors: Carter M. Armstrong, Richard Kowalczyk, Andrew Zubyk, Kevin Berg, Clark Meadows, Danny Chan, Thomas Schoemehl, Ramon Duggal, Nora Hinch, Richard B. TrueAbstract:The development of a compact radio Frequency (RF) vacuum power amplifier for High-resolution airborne radar is described. The amplifier, a microwave power module (MPM), operates in the upper millimeterwave Frequency band of 231.5-235 GHz providing a peak output power of 32 W. Common with previous Extremely High Frequency MPM development at Electron Devices, the G-band MPM consists of a periodic permanent magnet focused serpentine waveguide traveling wave tube (TWT) and a miniaturized 20-kV electronic power conditioner. Input drive to the MPM for saturation is around 10 mW. Low-loss chemical vapor deposition diamond WR-4.3 windows serve as the input and output ports of the TWT. Due to the High duty of the radar application, a four-stage TWT collector is employed for beam energy recovery. The MPM operates from a 270-Vdc power source. Two MPM configurations have been constructed: a single integrated unit for laboratory testing and a split-package configuration for integration in a standard electro-optical/infrared gimbal. The split-package flight test unit has a maximum prime power requirement of 176 W, corresponding to an overall amplifier efficiency of 9%. The radar sensor has been flown on a modified DC-3 test bed with High-resolution real-time video imagery obtained under cloud-obscured operating conditions.
E Prilutskii - One of the best experts on this subject based on the ideXlab platform.
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Extremely High Frequency piezoelectroacoustic transducer based on bn tube sic whiskers rope
Physica E-low-dimensional Systems & Nanostructures, 2007Co-Authors: V V Pokropivny, A V Pokropivny, A Lohmus, Runno Lohmus, S Kovrygin, P Sylenko, R Partch, E PrilutskiiAbstract:Innovative idea of piezoelectric electroacoustic transducer in Extremely High-Frequency terahertz range on the basis of BN-tube/SiC-whiskers rope is suggested and substantiated. Unlike an acoustic spectrum of solid rectangular pins and films used so far in ultrasonic pulsers and receivers, in the acoustic spectrum of circular hollow nanotubes, the peculiar squash E 2g and the subsequent E ng modes of starlike chain belonging to a gallery of whispering acoustic modes was shown by ab initio RHF/6-31 G calculations to exist in the Raman spectra. Inherent important feature of these standing vibrations is their weak attenuation and High Frequency, which, as depended on the nanotube diameter, fall in the range of about ∼1 GHz-1 THz. Hypersound was suggested to be excited by resonant microwaves using the piezoelectric properties of BN heteropolar nanotubes and then to transmit it into a sample by High modulus encapsulated SiC-whiskers. Such BN-tube/SiC-whiskers of 100-800 nm in diameter and with ∼20 aspect ratio were synthesized by carbothermal and CVD techniques. Cactus-like arrays of SiC nanowhiskers were synthesized by CVD technique. A sketch of the hypersound generator/detector, with the piezoelectroacoustical transducer on the basis of the BN-tube/SiC-whisker assembly serving as hypersonic antenna, was advanced.
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Extremely High-Frequency piezoelectroacoustic transducer based on BN-tube/SiC-whiskers rope
Physica E-low-dimensional Systems & Nanostructures, 2007Co-Authors: V V Pokropivny, A V Pokropivny, A Lohmus, Runno Lohmus, S Kovrygin, P Sylenko, R Partch, E PrilutskiiAbstract:Innovative idea of piezoelectric electroacoustic transducer in Extremely High-Frequency terahertz range on the basis of BN-tube/SiC-whiskers rope is suggested and substantiated. Unlike an acoustic spectrum of solid rectangular pins and films used so far in ultrasonic pulsers and receivers, in the acoustic spectrum of circular hollow nanotubes, the peculiar squash E 2g and the subsequent E ng modes of starlike chain belonging to a gallery of whispering acoustic modes was shown by ab initio RHF/6-31 G calculations to exist in the Raman spectra. Inherent important feature of these standing vibrations is their weak attenuation and High Frequency, which, as depended on the nanotube diameter, fall in the range of about ∼1 GHz-1 THz. Hypersound was suggested to be excited by resonant microwaves using the piezoelectric properties of BN heteropolar nanotubes and then to transmit it into a sample by High modulus encapsulated SiC-whiskers. Such BN-tube/SiC-whiskers of 100-800 nm in diameter and with ∼20 aspect ratio were synthesized by carbothermal and CVD techniques. Cactus-like arrays of SiC nanowhiskers were synthesized by CVD technique. A sketch of the hypersound generator/detector, with the piezoelectroacoustical transducer on the basis of the BN-tube/SiC-whisker assembly serving as hypersonic antenna, was advanced.
Carter M. Armstrong - One of the best experts on this subject based on the ideXlab platform.
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a compact Extremely High Frequency mpm power amplifier
IEEE Transactions on Electron Devices, 2018Co-Authors: Carter M. Armstrong, Richard Kowalczyk, Andrew Zubyk, Kevin Berg, Clark Meadows, Danny Chan, Thomas Schoemehl, Ramon Duggal, Nora Hinch, Richard B. TrueAbstract:The development of a compact radio Frequency (RF) vacuum power amplifier for High-resolution airborne radar is described. The amplifier, a microwave power module (MPM), operates in the upper millimeter-wave Frequency band of 231.5–235 GHz providing a peak output power of 32 W. Common with previous Extremely High Frequency MPM development at Electron Devices, the ${G}$ -band MPM consists of a periodic permanent magnet focused serpentine waveguide traveling wave tube (TWT) and a miniaturized 20-kV electronic power conditioner. Input drive to the MPM for saturation is around 10 mW. Low-loss chemical vapor deposition diamond WR-4.3 windows serve as the input and output ports of the TWT. Due to the High duty of the radar application, a four-stage TWT collector is employed for beam energy recovery. The MPM operates from a 270- $\text{V}_{\sf {dc}}$ power source. Two MPM configurations have been constructed: a single integrated unit for laboratory testing and a split-package configuration for integration in a standard electro-optical/infrared gimbal. The split-package flight test unit has a maximum prime power requirement of 176 W, corresponding to an overall amplifier efficiency of 9%. The radar sensor has been flown on a modified DC-3 test bed with High-resolution real-time video imagery obtained under cloud-obscured operating conditions.
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A Compact Extremely High Frequency MPM Power Amplifier
IEEE Transactions on Electron Devices, 2018Co-Authors: Carter M. Armstrong, Richard Kowalczyk, Andrew Zubyk, Kevin Berg, Clark Meadows, Danny Chan, Thomas Schoemehl, Ramon Duggal, Nora Hinch, Richard B. TrueAbstract:The development of a compact radio Frequency (RF) vacuum power amplifier for High-resolution airborne radar is described. The amplifier, a microwave power module (MPM), operates in the upper millimeterwave Frequency band of 231.5-235 GHz providing a peak output power of 32 W. Common with previous Extremely High Frequency MPM development at Electron Devices, the G-band MPM consists of a periodic permanent magnet focused serpentine waveguide traveling wave tube (TWT) and a miniaturized 20-kV electronic power conditioner. Input drive to the MPM for saturation is around 10 mW. Low-loss chemical vapor deposition diamond WR-4.3 windows serve as the input and output ports of the TWT. Due to the High duty of the radar application, a four-stage TWT collector is employed for beam energy recovery. The MPM operates from a 270-Vdc power source. Two MPM configurations have been constructed: a single integrated unit for laboratory testing and a split-package configuration for integration in a standard electro-optical/infrared gimbal. The split-package flight test unit has a maximum prime power requirement of 176 W, corresponding to an overall amplifier efficiency of 9%. The radar sensor has been flown on a modified DC-3 test bed with High-resolution real-time video imagery obtained under cloud-obscured operating conditions.
