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  1. Article ; Online: Synchrotron mechanism of X-ray and gamma-ray emissions in lightning and spark discharges.

    Petrov, N I

    Scientific reports

    2021  Volume 11, Issue 1, Page(s) 19824

    Abstract: X-ray and γ-ray emissions observed in lightning and long sparks are usually connected with the bremsstrahlung of high-energy runaway electrons. Here, an alternative physical mechanism for producing X-ray and gamma-ray emissions caused by the polarization ...

    Abstract X-ray and γ-ray emissions observed in lightning and long sparks are usually connected with the bremsstrahlung of high-energy runaway electrons. Here, an alternative physical mechanism for producing X-ray and gamma-ray emissions caused by the polarization current and associated electromagnetic field moving with relativistic velocity along a curved discharge channel has been proposed. The existence of fast electromagnetic surface waves propagating along the lightning discharge channel at a speed close to the speed of light in vacuum is shown. The possibility of the production of microwave, X-ray and gamma-ray emissions by a polarization current pulse moving along a curved path via synchrotron radiation mechanism is pointed out. The existence of long tails in the power spectrum is shown, which explains observations of photon energies in the range of 10-100 MeV in the terrestrial gamma-ray flashes, as well as measured power spectrum of laboratory spark discharge.
    Language English
    Publishing date 2021-10-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-021-99336-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Speed of structured light pulses in free space.

    Petrov, N I

    Scientific reports

    2019  Volume 9, Issue 1, Page(s) 18332

    Abstract: A plane monochromatic wave propagates in vacuum at the velocity c. However, wave packets limited in space and time are used to transmit energy and information. Here it has been shown based on the wave approach that the on-axis part of the pulsed beams ... ...

    Abstract A plane monochromatic wave propagates in vacuum at the velocity c. However, wave packets limited in space and time are used to transmit energy and information. Here it has been shown based on the wave approach that the on-axis part of the pulsed beams propagates in free space at a variable speed, exhibiting both subluminal and superluminal behaviours in the region close to the source, and their velocity approaches the value of c with distance. Although the pulse can travel over small distances faster than the speed of light in vacuum, the average on-axis velocity, which is estimated by the arrival time of the pulse at distances z ≫ l
    Language English
    Publishing date 2019-12-04
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-019-54921-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Small-Sized Interferometer with Fabry-Perot Resonators for Gravitational Wave Detection.

    Petrov, Nikolai / Pustovoit, Vladislav

    Sensors (Basel, Switzerland)

    2021  Volume 21, Issue 5

    Abstract: It is highly desirable to have a compact laser interferometer for detecting gravitational waves. Here, a small-sized tabletop laser interferometer with Fabry-Perot resonators consisting of two spatially distributed "mirrors" for detecting gravitational ... ...

    Abstract It is highly desirable to have a compact laser interferometer for detecting gravitational waves. Here, a small-sized tabletop laser interferometer with Fabry-Perot resonators consisting of two spatially distributed "mirrors" for detecting gravitational waves is proposed. It is shown that the spectral resolution of 10
    Language English
    Publishing date 2021-03-08
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s21051877
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: [Innovative methods for extracting biolactive сompounds from plant materials].

    Sidorova, Yu S / Petrov, N A / Zorin, S N / Mazo, V K

    Voprosy pitaniia

    2023  Volume 92, Issue 6, Page(s) 28–37

    Abstract: Modern methods for extracting bioactive сompounds (BAC) from various raw materials are focused on efficacy and environmental awareness, involve the use of mathematical and statistical optimization methods, the choice of green solvents, and the use of ... ...

    Abstract Modern methods for extracting bioactive сompounds (BAC) from various raw materials are focused on efficacy and environmental awareness, involve the use of mathematical and statistical optimization methods, the choice of green solvents, and the use of additive extraction technology.
    MeSH term(s) Food ; Food Ingredients ; Food Safety ; Microwaves ; Solvents
    Chemical Substances Food Ingredients ; Solvents
    Language Russian
    Publishing date 2023-10-30
    Publishing country Russia (Federation)
    Document type Review ; English Abstract ; Journal Article
    ZDB-ID 414734-0
    ISSN 0042-8833
    ISSN 0042-8833
    DOI 10.33029/0042-8833-2023-92-6-28-38
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Focusing of beams into subwavelength area in an inhomogeneous medium.

    Petrov, N

    Optics express

    2009  Volume 9, Issue 12, Page(s) 658–673

    Abstract: Propagation and focusing of nonparaxial Gaussian beams with spherical wavefront in a graded-index medium are investigated using quantum-theoretical method of coherent states. Explicit expressions for the trajectory and width of a beam taking into account ...

    Abstract Propagation and focusing of nonparaxial Gaussian beams with spherical wavefront in a graded-index medium are investigated using quantum-theoretical method of coherent states. Explicit expressions for the trajectory and width of a beam taking into account all correction terms to the paraxial approximation have been obtained. Electromagnetic field distributions in longitudinal and lateral directions are simulated. Diffraction of strongly focused high-aperture wave beams is investigated theoretically. The ratio of intensities of evanescent and propagating fields is calculated for different values of focused spot.
    Language English
    Publishing date 2009-07-06
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1491859-6
    ISSN 1094-4087 ; 1094-4087
    ISSN (online) 1094-4087
    ISSN 1094-4087
    DOI 10.1364/oe.9.000658
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: First Report of Tomato spotted wilt virus on a New Host Leuzea carthamoides in Bulgaria and the World.

    Dikova, B / Petrov, N / Djourmanski, A / Lambev, H

    Plant disease

    2019  Volume 97, Issue 9, Page(s) 1258

    Abstract: The Siberian plant Leuzea carthamoides or maral root was introduced to Europe as a medicinal crop. Tomato spotted wilt virus (TSWV), genus Tospovirus, family Bunyaviridae, caused a harmful outbreak on L. carthamoides in central Bulgaria near the town of ... ...

    Abstract The Siberian plant Leuzea carthamoides or maral root was introduced to Europe as a medicinal crop. Tomato spotted wilt virus (TSWV), genus Tospovirus, family Bunyaviridae, caused a harmful outbreak on L. carthamoides in central Bulgaria near the town of Kazanluk in 2009. In 2011, TSWV was identified on young sprouts from the rootages of L. carthamoides in the same place near the town of Kazanluk, Bulgaria, by means of indicator (test) plants, double antibody sandwich (DAS)-ELISA, and reverse transcription (RT)-PCR. Disease symptoms were small yellow spots on the young leaves grown from the tested sprouts and distortions of the leaf lamina. The old leaves had large yellow spots and necrosis, without deformations. Most of those L. carthamoides plants with such symptoms died in the second and third year. The number of the plants in the plantations decreased 20 to 40% during the 3-year period and some of these losses were from the virus disease except the environment conditions. DAS-ELISA was carried out with polyclonal TSWV antiserum of LOEWE Biochemica, GmbH, Germany. We obtained positive extinction values OD
    Language English
    Publishing date 2019-02-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 754182-x
    ISSN 0191-2917
    ISSN 0191-2917
    DOI 10.1094/PDIS-11-12-1005-PDN
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Simulating behavior to help researchers build experiments.

    de Leeuw, Joshua R / Gilbert, Rebecca A / Petrov, Nikolay / Luchterhandt, Björn

    Behavior research methods

    2022  Volume 55, Issue 4, Page(s) 1863–1873

    Abstract: Testing that an experiment works as intended is critical for identifying design problems and catching technical errors that could invalidate the results. Testing is also time-consuming because of the need to manually run the experiment. This makes ... ...

    Abstract Testing that an experiment works as intended is critical for identifying design problems and catching technical errors that could invalidate the results. Testing is also time-consuming because of the need to manually run the experiment. This makes testing the experiment costly for researchers, and therefore testing is less comprehensive than in other kinds of software development where tools to automate and speed up the testing process are widely used. In this paper, we describe an approach that substantially reduces the time required to test behavioral experiments: automated simulation of participant behavior. We describe how software that is used to build experiments can use information contained in the experiment's code to automatically generate plausible participant behavior. We demonstrate this through an implementation using jsPsych. We then describe four potential scenarios where automated simulation of participant behavior can improve the way researchers build experiments. Each scenario includes a demo and accompanying code. The full set of examples can be found at https://jspsych.github.io/simulation-examples/ .
    MeSH term(s) Humans ; Software ; Computer Simulation
    Language English
    Publishing date 2022-06-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 231560-9
    ISSN 1554-3528 ; 0743-3808 ; 1554-351X
    ISSN (online) 1554-3528
    ISSN 0743-3808 ; 1554-351X
    DOI 10.3758/s13428-022-01899-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Role of Elevated Serum TGF-β1 and the Common Promoter

    Aleksandrova, Elina / Mindov, Ivan / Petrov, Bozhidar / Dimitrova, Ivelina / Petrov, Nikolay / Ananiev, Julian / Vlaykova, Tatyana / Valkanov, Stefan

    Medicina (Kaunas, Lithuania)

    2024  Volume 60, Issue 1

    Abstract: Background and ... ...

    Abstract Background and Objectives
    MeSH term(s) Humans ; Transforming Growth Factor beta1/genetics ; Glioma ; Brain Neoplasms/genetics ; Polymorphism, Genetic ; Cytokines
    Chemical Substances Transforming Growth Factor beta1 ; Cytokines ; TGFB1 protein, human
    Language English
    Publishing date 2024-01-13
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2188113-3
    ISSN 1648-9144 ; 1010-660X
    ISSN (online) 1648-9144
    ISSN 1010-660X
    DOI 10.3390/medicina60010146
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: [Physiological and biochemical

    Shipelin, V A / Biryulina, N A / Sidorova, Yu S / Petrov, N A / Zorin, S N / Mazo, V K / Bessonov, V V

    Voprosy pitaniia

    2024  Volume 93, Issue 1, Page(s) 80–91

    Abstract: Increasing the ability of the human body to adapt to physical stress is relevant from the standpoint of using foods for special uses containing functional food ingredients (FFI) with effectiveness proven in vivo. ...

    Abstract Increasing the ability of the human body to adapt to physical stress is relevant from the standpoint of using foods for special uses containing functional food ingredients (FFI) with effectiveness proven in vivo.
    MeSH term(s) Humans ; Rats ; Male ; Animals ; Rats, Wistar ; Chenopodium quinoa ; Polyphenols/pharmacology ; Corticosterone ; Dinoprostone
    Chemical Substances Polyphenols ; Corticosterone (W980KJ009P) ; Dinoprostone (K7Q1JQR04M)
    Language Russian
    Publishing date 2024-01-19
    Publishing country Russia (Federation)
    Document type English Abstract ; Journal Article
    ZDB-ID 414734-0
    ISSN 0042-8833
    ISSN 0042-8833
    DOI 10.33029/0042-8833-2024-93-1-80-91
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: The Effect of Semi-Synthetic and High-Fat High-Carbohydrate Diets Containing Cholesterol on Lipid and Cholesterol Metabolism in Male Wistar Rats.

    Biryulina, N A / Sidorova, Yu S / Petrov, N A / Guseva, G V / Mazo, V K

    Bulletin of experimental biology and medicine

    2023  Volume 175, Issue 4, Page(s) 454–458

    Abstract: The choice of an optimal biological model of exogenous hypercholesterolemia is necessary for correct assessment of the cholesterol-lowering properties of bioactive substances and specialized food products and for validity of the experimental results. We ... ...

    Abstract The choice of an optimal biological model of exogenous hypercholesterolemia is necessary for correct assessment of the cholesterol-lowering properties of bioactive substances and specialized food products and for validity of the experimental results. We studied the effects of cholesterol consumption in the composition of the standard semi-synthetic diet and high-fat high-carbohydrate diet for more than 3 months on lipid and cholesterol metabolism in male Wistar rats. Our findings suggest that cholesterol consumption in both diets led to a significant impairment of lipid and cholesterol metabolism, as well as an increase in insulin resistance in rats.
    Language English
    Publishing date 2023-09-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 390407-6
    ISSN 1573-8221 ; 0007-4888 ; 0365-9615
    ISSN (online) 1573-8221
    ISSN 0007-4888 ; 0365-9615
    DOI 10.1007/s10517-023-05884-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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