94 research outputs found

    Long-time dynamics of Rouse-Zimm polymers in dilute solutions with hydrodynamic memory

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    The dynamics of flexible polymers in dilute solutions is studied taking into account the hydrodynamic memory, as a consequence of fluid inertia. As distinct from the Rouse-Zimm (RZ) theory, the Boussinesq friction force acts on the monomers (beads) instead of the Stokes force, and the motion of the solvent is governed by the nonstationary Navier-Stokes equations. The obtained generalized RZ equation is solved approximately. It is shown that the time correlation functions describing the polymer motion essentially differ from those in the RZ model. The mean-square displacement (MSD) of the polymer coil is at short times \~ t^2 (instead of ~ t). At long times the MSD contains additional (to the Einstein term) contributions, the leading of which is ~ t^(1/2). The relaxation of the internal normal modes of the polymer differs from the traditional exponential decay. It is displayed in the long-time tails of their correlation functions, the longest-lived being ~ t^(-3/2) in the Rouse limit and t^(-5/2) in the Zimm case, when the hydrodynamic interaction is strong. It is discussed that the found peculiarities, in particular an effectively slower diffusion of the polymer coil, should be observable in dynamic scattering experiments.Comment: 6 page

    Stochastic Dynamics of Bionanosystems: Multiscale Analysis and Specialized Ensembles

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    An approach for simulating bionanosystems, such as viruses and ribosomes, is presented. This calibration-free approach is based on an all-atom description for bionanosystems, a universal interatomic force field, and a multiscale perspective. The supramillion-atom nature of these bionanosystems prohibits the use of a direct molecular dynamics approach for phenomena like viral structural transitions or self-assembly that develop over milliseconds or longer. A key element of these multiscale systems is the cross-talk between, and consequent strong coupling of, processes over many scales in space and time. We elucidate the role of interscale cross-talk and overcome bionanosystem simulation difficulties with automated construction of order parameters (OPs) describing supra-nanometer scale structural features, construction of OP dependent ensembles describing the statistical properties of atomistic variables that ultimately contribute to the entropies driving the dynamics of the OPs, and the derivation of a rigorous equation for the stochastic dynamics of the OPs. Since the atomic scale features of the system are treated statistically, several ensembles are constructed that reflect various experimental conditions. The theory provides a basis for a practical, quantitative bionanosystem modeling approach that preserves the cross-talk between the atomic and nanoscale features. A method for integrating information from nanotechnical experimental data in the derivation of equations of stochastic OP dynamics is also introduced.Comment: 24 page

    Synchronization, Control and Stability of Fractional Order Hyperchaotic Systems in The Context of The Generalized Memory

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    In the article offered fractional kinetic model of networks with generalized memory. On the basis of fractional kinetic model network with hyperchaotic systems, embedded in a percolation structure, realized task topologically synchronization. While tracing control and stability. Criterion ndash ldquoproximityrdquo capture average return time Poincare. Shows a visualization of results

    On solving Schwinger-Dyson equations for non-Abelian gauge theory

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    A method for solving Schwinger-Dyson equations for the Green function generating functional of non-Abelian gauge theory is proposed. The method is based on an approximation of Schwinger-Dyson equations by exactly soluble equations. For the SU(2) model the first step equations of the iteration scheme are solved which define a gauge field propagator. Apart from the usual perturbative solution, a non-perturbative solution is found which corresponds to the spontaneous symmetry breaking and obeys infrared finite behaviour of the propagator.Comment: 12 pages, Plain LaTeX, no figures, extended and revised version published in Journal of Physics

    Preliminary results of the Cerenkov EAS flashes the Crimean Astrophysical Observatory

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    The facility designed for the study of angular resolution of light in the extensive air showers EAS flashes is described. The threshold energy of the facility is about 3 x 10 to the 12h power eV. The data on the angular distribution of light in a flash and the ratio of the flux in the UV and visual region as a function of the distance to the axis of a shower are given. Obtained results are compared to the published computations

    IN SEARCH OF SELF-IDENTITY: JEWS IN THE CONTEXT OF THE RUSSIAN CULTURE

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    The article focuses on the formation of cultural and social self-identification of an ethnic minority within a multicultural society as well as on the establishment and functioning of a state as a conglomerate of various ethnic constituents. Nowadays this subject is vital, as many European countries have found themselves in a situation under which they have to host numerous migrants and assimilate them. It should be emphasized that minorities, their way of life, language they speak and education their children get always reflect general trends existing in the society as well as the official policy towards minorities, prejudices or lack of prejudices in the society. In this study, the authors investigate the possibility of integration and assimilation as well as the historical and social conditions necessary for assimilation in a society and for understanding its importance within a community. Integration means acceptance of a new culture, language and traditions, better understanding of a new religion and ethnic characteristics in order to be a part of a hosting society. It is the history of the Jewish community in Russia, which is analyzed in the article. Since the aim of the present study is the understanding of self-identification, i.e. personal self-perception of an individual in the society, of great value are the memoirs as sources of information and their textual analysis. The objectives of the research are to study the main aspects of social life: religion, education, language. Based on the exact results, the conclusion may be regarded as universal and generally applicable when forming ways of integration of minorities into a single public space

    The effectiveness of physical activity in cardiorehabilitation

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    The review shows that the molecular mechanisms initiated by physical exertion underlie the multifactorial influence of the latter on the function of the cardiovascular system and the course of cardiac diseases. Exercise is an important component of the therapeutic treatment in patients with cardiovascular diseases, which is confirmed by the results of a meta­analysis that included 63 studies that were associated with various forms of aerobic exercise of different intensity (from 50 to 95 % VO2) for 1 to 47 months, which showed that exercise-based CR improves cardiovascular function. Knowledge of the molecular basis of the impact of physical activity makes it possible to use biochemical markers to assess the effectiveness of rehabilitation programs

    Meson vacuum phenomenology in a three-flavor linear sigma model with (axial-)vector mesons

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    We study scalar, pseudoscalar, vector, and axial-vector mesons with non-strange and strange quantum numbers in the framework of a linear sigma model with global chiral U(Nf)L×U(Nf)RU(N_f)_L \times U(N_f)_R symmetry. We perform a global fit of meson masses, decay widths, as well as decay amplitudes. The quality of the fit is, for a hadronic model that does not consider isospin-breaking effects, surprisingly good. We also investigate the question whether the scalar qˉq\bar{q}q states lie below or above 1 GeV and find the scalar states above 1 GeV to be preferred as qˉq\bar{q}q states. Additionally, we also describe the axial-vector resonances as qˉq\bar{q}q states.Comment: 29 pages, 4 figures, 3 tables. v2 is the updated version after referee remarks (dilaton field discussed, a new figure added

    Phenomenological features of mortality and morbidity dynamics in Tomsk versus heliogeophysical activity

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    The influence of heliogeophysical activity on the morbidity and mortality of the population in Tomsk is studied epidemiologically on the basis of regional data. The biological effectiveness of heliogeophysical factors selected on the basis of the Karhunen–Loeve method from epidemiological data on the morbidity and mortality in Tomsk in 1990–2008 is estimated. An analysis of the impact of variations in heliogeophysical activity on morbidity and mortality (according to the International Statistical Classification of Diseases and Related Health, ICD-10) showed the existence of common factors within different nosological classes that reliably correlate with the major components of variations in characteristic indices of heliogeophysical activity

    Brownian oscillators driven by correlated noise in a moving trap

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    Brownian oscillator, i.e. a micron-sized or smaller particle trapped in a thermally fluctuating environment is studied. The confining harmonic potential can move with a constant velocity. As distinct from the standard Langevin theory, the chaotic force driving the particle is correlated in time. The dynamics of the particle is described by the generalized Langevin equation with the inertial term, a coloured noise force, and a memory integral. We consider two kinds of the memory in the system. The first one corresponds to the exponentially correlated noise in a weakly viscoelastic fluid and in the second case the memory naturally arises within the Navier-Stokes hydrodynamics. Exact analytical solutions are obtained in both the cases using a simple and effective method not applied so far in this kind of problems.Comment: Presented at the 17th International Conference Applied Physics of Condensed Matter (APCOM 2011), Novy Smokovec, High Tatras, Slovakia, June 22 - 24, 201
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