57 research outputs found

    Propagation of weak waves in the inhomogeneous elastoviscoplastic medium with a cell structure

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    Non-stationary acceleration waves in the fluid-saturated inhomogeneous elastoviscoplastic porous medium are studied using the mathematical theory of discontinuities. The equations for determining the intensity and the geometry of wave fronts of the fluidsaturated elastoviscoplastic medium were first derived. It is shown that in the medium under consideration there are two types of irrotational waves and one equivoluminal wave, that are equal to the velocities in the homogeneous elastic porous media at every point

    ACOUSTIC WAVES EMISSION IN THE TWO-COMPONENT HEREDITARY-ELASTIC MEDIUM

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    Summary. On the dynamics of two-component media a number of papers, which address the elastic waves in a homogeneous, unbounded fluid-saturated porous medium. In other studies address issues of dissipative processes in harmonic deformation hereditary elastic medium. In the article the dissipative processes of the viscoelastic porous medium, which hereditary properties are described by the core relaxation fractional exponential function U.N. Rabotnova integro-differential Boltzmann-Volterr ratio, harmonic deformation by the straining saturated incompressible liquid are investigated. Speed of wave propagation, absorption coefficient, mechanical loss tangent, logarithmic decrement, depending on fractional parameter γ, determining formulas received. The frequency logarithm and temperature graph dependences with the goal fractional parameter are constructed. Shows the dependences velocity and attenuation coefficient of the tangent of the phase angle of the logarithm of the temperature, and the dependence of the attenuation coefficient of the logarithm of the frequency. Dependencies the speed and the tangent of the phase angle of the frequency identical function of the logarithm of temperature

    The Dynamic Deformation of Three-Component Porous Media

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    A mathematical model of the dynamic deformation of three-component elastic media saturated with liquid and gas, given by elastic moduli and coefficients characterizing the porosity and compressibility of the liquid and gas, is considered. Formulas for determining the propagation velocity of monochromatic waves in ternary porous media are obtained. The existence of three longitudinal waves depends on the discriminant of a cubic equation and the velocity ratio

    Issues of the Integrated Processing of Gradient Measurements in High Sensitive Magnetometry

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    Поступила: 15.04.2019. Принята в печать: 25.06.2019.Received: 15.04.2019. Accepted: 25.06.2019.В интересах снижения влияния собственного магнитного поля носителя магнитометрической аппаратуры на показания магнитометра исследованы градиенты 1-го и 2-го порядков для z-компоненты вектора магнитной индукции произвольно ориентированного магнитного диполя. Рассмотрены особенности совместной обработки градиентных измерений.We explore the first and the second-order of the derivative magnetic flux vector in relation to altitude in order to reduce internal magnetic field of the magnetometric equipment carrier influence on the readings of the vector supersensitive magnetometer. We consider the details of gradient measurements integrated processing in multidirectional magnetic dipole approximation. The average intensity altitude-component in the second-order gradiometer is by an order of magnitude more than one of the firstorder gradiometer without regard to the distance between the magnetic dipole and sensor. We confirm that every first and second-order gradient altitude-component disappears in the half-domain of the spherical angular values definition. The integrated processing of gradient measurements imposes the constraint on the domain of the spherical angular values definition. We conclude that this constraint may be controlled by limiting the corrected gradient projection in relation to the root-mean-square deviation

    Cytogenomic Profile of Uterine Leiomyoma: In Vivo vs. In Vitro Comparison

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    We performed a comparative cytogenomic analysis of cultured and uncultured uterine leiomyoma (UL) samples. The experimental approach included karyotyping, aCGH, verification of the detected chromosomal abnormalities by metaphase and interphase FISH, MED12 mutation analysis and telomere measurement by Q-FISH. An abnormal karyotype was detected in 12 out of 32 cultured UL samples. In five karyotypically abnormal ULs, MED12 mutations were found. The chromosomal abnormalities in ULs were present mostly by complex rearrangements, including chromothripsis. In both karyotypically normal and abnormal ULs, telomeres were ~40% shorter than in the corresponding myometrium, being possibly prerequisite to chromosomal rearrangements. The uncultured samples of six karyotypically abnormal ULs were checked for the detected chromosomal abnormalities through interphase FISH with individually designed DNA probe sets. All chromosomal abnormalities detected in cultured ULs were found in corresponding uncultured samples. In all tumors, clonal spectra were present by the karyotypically abnormal cell clone/clones which coexisted with karyotypically normal ones, suggesting that chromosomal abnormalities acted as drivers, rather than triggers, of the neoplastic process. In vitro propagation did not cause any changes in the spectrum of the cell clones, but altered their ratio compared to uncultured sample. The alterations were unique for every UL. Compared to its uncultured counterpart, the frequency of chromosomally abnormal cells in the cultured sample was higher in some ULs and lower in others. To summarize, ULs are characterized by both inter- and intratumor genetic heterogeneity. Regardless of its MED12 status, a tumor may be comprised of clones with and without chromosomal abnormalities. In contrast to the clonal spectrum, which is unique and constant for each UL, the clonal frequency demonstrates up or down shifts under in vitro conditions, most probably determined by the unequal ability of cells with different genetic aberrations to exist outside the body

    DYNAMIC DEFORMATION THE VISCOELASTIC TWOCOMPONENT MEDIUM

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    Summary. In the article are scope harmonious warping of the two-component medium, one component which are represent viscoelastic medium, hereditary properties which are described by the kernel aftereffect Abel integral-differential ratio BoltzmannVolterr, while second – compressible liquid. Do a study one-dimensional case. Use motion equation of two-component medium at movement. Look determination system these equalization in the form of damped wave. Introduce dimensionless coefficient. Combined equations happen to homogeneous system with complex factor relatively waves amplitude in viscoelastic component and in fluid. As a result opening system determinant receive biquadratic equation. Elastic operator express through kernel aftereffect Abel for space Fourier. With the help transformation and symbol series biquadratic equation reduce to quadratic equation. Come to the conclusion that in two-component viscoelastic medium exist two mode sonic waves. As a result solution of quadratic equation be found description advance of waves sonic in viscoelastic two-component medium, which physical-mechanical properties represent complex parameter. Velocity determination advance of sonic waves, attenuation coefficient, mechanical loss tangent, depending on characteristic porous medium and circular frequency formulas receive. Graph dependences of description advance of waves sonic from the temperature logarithm and with the fractional parameter γ are constructed
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