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Siberian Fan Reliefs and the Tunguska Cosmic Body

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Natural Science 2021年第12期13卷 510-517页

作者： valery v. Burmakin Alexander Yastrebov Local Historian Zelenogorsk Russia Krypton Ltd. Bryansk Russia

Unusual reliefs on the Earth’s surface were found in aerial photographs of Eastern Siberia in the late 20th century. The facts justifying the connection are given by Siberian Fan Reliefs and the Tunguska Cosmic Body.... 详细信息

Unusual reliefs on the Earth’s surface were found in aerial photographs of Eastern Siberia in the late 20thverdana;"> century. The facts justifying the connection are given by Siberian Fan Reliefs and the Tunguska Cosmic Body. It is most natural to assume that we are dealing with the falling of numerous fragments of a collapsed comet. The more likely version is that the comet is captured by the Earth-Moon system and remains in Earth orbit for some time.

关键词： Siberian Fan Reliefs Tunguska Catastrophe Tunguska Cosmic Body

Spherically Symmetric Problem of General Relativity for a Fluid Sphere

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Journal of Modern Physics 2024年第4期15卷 401-415页

作者： valery v. vasiliev Leonid v. Fedorov Institute of Applied Mechanics of Russian Academy of Sciences Moscow Russia

The paper is devoted to a spherically symmetric problem of General Relativity (GR) for a fluid sphere. The problem is solved within the framework of a special geometry of the Riemannian space induced by gravitation. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space allows us to obtain complete set of GR equations for the external empty space and the internal spaces for incompressible and compressible perfect fluids. The obtained analytical solution for an incompressible fluid is compared with the Schwarzchild solution. For a sphere consisting of compressible fluid or gas, a numerical solution is presented and discussed.

关键词： General Relativity Spherically Symmetric Problem Fluid Sphere

To the Solution of a Spherically Symmetric Problem of General Relativity

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Journal of Modern Physics 2023年第2期14卷 147-159页

作者： valery v. vasiliev Leonid v. Fedorov Russian Academy of Sciences Moscow Russia

The paper is devoted to the spherically symmetric problem of General Relativity. Existing solutions obtained by K. Schwarzschild and v. Fock are presented and discussed. A special geometry of the Riemannian space induced by gravitation is proposed. According to this geometry the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. The solution of the Einstein equations for the empty space with this geometry coincides with the solution in Gullstand-Painlever coordinates. In application to the found solution, the problem of the light trajectory deviation in the vicinity of Sun and the problem of escape velocity are discussed.

关键词： General Relativity Spherically Symmetric Problem

Spherically Symmetric Problem of General Relativity for an Elastic Solid Sphere

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Journal of Modern Physics 2023年第6期14卷 818-832页

作者： valery v. vasiliev Leonid v. Fedorov Russian Academy of Sciences Moscow Russia

The paper is devoted to a spherically symmetric problem of General Relativity (GR) for an elastic solid sphere. Originally developed to describe gravitation in continuum (vacuum, gas, fluid and solid) GR does not provide the complete set of equations for solids and, in contrast to the Newton gravitation theory, does not allow us to study the stresses induced by gravitation in solids, because the compatibility equations which are attracted in the Euclidean space for this purpose do not exist in the Riemannian space. To solve the problem within the framework of GR, a special geometry of the Riemannian space induced by gravitation is proposed. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space in GR allows us to supplement the conservation equations for the energy-momentum tensor with compatibility equations of the theory of elasticity and to arrive to the complete set of equations for stresses. The analytical solution of the Einstein equations for the empty space surrounding the sphere and the numerical solution for the internal space inside the sphere with the proposed geometry are presented and discussed.

关键词： General Relativity Spherically Symmetric Problem Elastic Sphere

Development of sorghum mutants with improved in vitro protein digestibility by CRISPR/Cas9 editing of kafirin genes

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The Crop Journal 2023年第5期11卷 1411-1418页

作者： Lev A.Elkonin Grigoriy A.Gerashchenkov Natalie v.Borisenko Odyssey A.Kenzhegulov Saule Kh.Sarsenova Natalya A.Rozhnova valery M.Panin Federal Centre of Agriculture Research of South-East Region Saratov 410010Russia Institute of Biochemistry and Genetics-Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences Ufa 450054Russia

Sorghum(Sorghum bicolor(L.) Moench) is a major world crop that is a reliable source of fodder and food grain in arid regions. However, unlike other cereals, sorghum grain has low nutritional value, owing mainly to the resistance of its storage proteins(kafirins) to protease digestion. Changing the composition of kafirins or their primary structure may address this problem. To induce mutations in kafirin-encoding genes that were expected to disturb their accumulation in endosperm cells, we used a genome-editing approach. By Agrobacterium-mediated genetic transformation of immature embryos of cv. Avans, we obtained 14 transgenic plants with genetic constructs for site-directed mutagenesis of the k1C5 and g KAF1 genes encoding 22 k Da a-and 28 kDa γ-kafirins, respectively. Sequencing of 5 regenerants obtained by using k1C5-addressing vector revealed two plants with mutations. T_1 progeny of these mutants had higher in vitro digestibility of endosperm proteins(86%–92%), in comparison with the donor Avans(63%–67%). The kernels of these plants had a thick vitreous endosperm. A mutant with increased in vitro protein digestibility and vitreous endosperm, carrying a mutation in the target sequence, was also obtained by use of the gKAF1-addressing vector. Thus, using genome editing technology, we have obtained mutants with improved kafirin digestibility that can be used in sorghum breeding.

关键词： Sorghum CRISPR/Cas Kafirins In vitro protein digestibility vitreous endosperm

To the Complete Set of Equations for a Static Problem of General Relativity

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Journal of Modern Physics 2019年第12期10卷 1401-1415页

作者： valery v. vasiliev Leonid v. Fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the formulation of the static problem of general relativity. As known, this problem is reduced to ten equations for the compo-nents of the Einstein tensor and the solution of these equations is associated with two principal problems. First, since the components of the Einstein tensor identically satisfy four conservation equations, only six of these equations are mutually independent. So, the set of the Einstein equations actually contains six independent equations for ten components of the metric tensor and should be supplemented with four additional equations which are missing in the original theory. Second, for a deformable solid the Einstein tensor is associated with the energy tensor which is expressed in terms of six stresses induced by gravitation. These stresses are not known and the relativity theory does not propose any equations for them. Thus, the static problem of general relativity cannot be properly formulated because the set of governing equations is not complete. In the paper, the problem of completeness of the general relativity governing set of equations is analyzed in application to the spherically symmetric static problem and the proposed approach is further described for the general case. As an example, linearized axisymmetric problem is considered.

关键词： General Relativity Coordinate Conditions Compatibility Stress Equations Spherically Symmetric Problem

Linearized Equations of General Relativity and the Problem of Reduction to the Newton Theory

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Journal of Modern Physics 2020年第2期11卷 221-236页

作者： valery v. vasiliev Leonid v. Fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the problem of reduction of the general relativity theory to the Newton gravitation theory for a gravitation field with relatively low intensity. This problem is traditionally solved on the basis of linearized equations of general relativity which, being matched to the Newton theory equations, allow us to link the classical gravitation constant with the constant entering the general relativity equations. Analysis of the linearized general relativity equations shows that it can be done only for empty space in which the energy tensor is zero. In solids, the set of linearized general relativity equations is not consistent and is not reduced to the Newton theory equations. Specific features of the problem are demonstrated with the spherically symmetric static problem of general relativity which has the closed-form solution.

关键词： General Relativity Gravitation Constant Linearized Equations Spherically Symmetric Problem

To the Schwarzschild Solution in General Relativity

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Journal of Modern Physics 2018年第14期9卷 2482-2494页

作者： valery v. vasiliev Leonid v. Fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the history of the spherically symmetric static problem solution of General Relativity found in 1916 by K. Schwarzschild [1] [2] which is interpreted in modern physics as the background of the objects referred to as Black Holes. First, the modern interpretation this solution which does not exactly coincide with original solution obtained by K. Schwarzschild is discussed. Second, the basic equations of the original Schwarzschild solution are presented in modern notations allowing us to compare existing and original solutions. Finally, a modification of the Schwarzschild approach is proposed allowing us to arrive at the exact solution of the Schwarzschild problem.

关键词： General Relativity Spherically Symmetric Problem Schwarzschild’s Solution Black Holes

Meso-substituted cationic 3-and 4-N-Pyridylporphyrins and their Zn(II)derivatives for antibacterial photodynamic therapy

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 1-16页

作者： Aram G.Gyulkhandanyan Marina H.Paronyan Anna G.Gyulkhandanyan Karapet R.Ghazaryan Marina v.Parkhats Boris M.Dzhagarov Maria v.Korchenova Ekaterina N.Lazareva Elena S.Tuchina Grigor v.Gyulkhandanyan valery v.Tuchin H.Buniatyan Institute of Biochemistry National Academy of Sciences of Armenia 5/1 Paruir Sevak Street Yerevan 0014Armenia INSERM U1204 Universite d'Evry vald'Essonne-Universite Paris-Saclay 1 Ruedu Pere JarlanBatiment Maupertuis91025Evry-CourcouronnesFrance B.I.Stepanov Institute of Physics National Academy of Sciences of Belarus 68-2 Nezavisimosti AvenueMinsk 220072Belarus Science Medical Center Saratov State University 83 Astrakhanskaya StreetSaratov 410012Russia Laboratory of Laser Molecular Imaging and Machine Learning(LMIML)National Research Tomsk State University 36 Lenin Avenue Tomsk 634050Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precision Mechanics and Control Russian Academy of Sciences Saratov 410028Russia

Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy(APDT)is one of the most promising and innovative approaches for the destruction of pathogenic *** the photosensitizers(PSs),compounds based on cationic porphyrins/metalloporphyrins are most successfully used to inactivate *** of meso-substituted cationic pyridylporphyrins and metalloporphyrins with various peripheral groups in the third and fourth positions of the pyrrole ring have been synthesized in *** aim of this work was to determine and test the most e®ective cationic porphyrins and metalloporphyrins with high photoactivity against Gram negative and Gram positive *** was shown that the synthesized cationic pyridylporphyrins/metalloporphyrins exhibit a high degree of phototoxicity towards both types of bacteria,including the methicillinresistant *** *** complexes of porphyrins are more phototoxic than metal-free porphyrin *** e®ectiveness of these Zn–metalloporphyrins on bacteria is consistent with the level of singlet oxygen *** was found that the high antibacterial activity of the studied cationic porphyrins/metalloporphyrins depends on four factors:the presence in the porphyrin macrocycle of a positive charge(+4),a central metal atom(Zn2þÞand hydrophobic peripheral functional groups as well as high values of quantum yields of singlet *** results indicate that meso-substituted cationic pyridylporphyrins/metalloporphyrins cannd wider application in photoinactivation of bacteria than anionic or neutral PSs usually used in APDT.

关键词： Antibacterial photodynamic therapy cationic porphyrins/metalloporphyrins phototoxicity Zn-metalloporphyrins singlet oxygen quantum yield Gram negative and Gram positive bacteria S.aureus MRSA E.coli Salmonella typhimurium.