94 research outputs found
Long-time dynamics of Rouse-Zimm polymers in dilute solutions with hydrodynamic memory
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
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
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
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
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
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
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
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 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 states lie below or above 1 GeV and find the
scalar states above 1 GeV to be preferred as states. Additionally,
we also describe the axial-vector resonances as 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
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
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
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