93 research outputs found
Monotone Causality in Opportunistically Stochastic Shortest Path Problems
When traveling through a graph with an accessible deterministic path to a
target, is it ever preferable to resort to stochastic node-to-node transitions
instead? And if so, what are the conditions guaranteeing that such a stochastic
optimal routing policy can be computed efficiently? We aim to answer these
questions here by defining a class of Opportunistically Stochastic Shortest
Path (OSSP) problems and deriving sufficient conditions for applicability of
non-iterative label-setting methods. The usefulness of this framework is
demonstrated in two very different contexts: numerical analysis and autonomous
vehicle routing. We use OSSPs to derive causality conditions for
semi-Lagrangian discretizations of anisotropic Hamilton-Jacobi equations. We
also use a Dijkstra-like method to solve OSSPs optimizing the timing and
urgency of lane change maneuvers for an autonomous vehicle navigating road
networks with a heterogeneous traffic load
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
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
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
- 24, 201
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
Hydrodynamic interactions and Brownian forces in colloidal suspensions: Coarse-graining over time and length-scales
We describe in detail how to implement a coarse-grained hybrid Molecular
Dynamics and Stochastic Rotation Dynamics simulation technique that captures
the combined effects of Brownian and hydrodynamic forces in colloidal
suspensions. The importance of carefully tuning the simulation parameters to
correctly resolve the multiple time and length-scales of this problem is
emphasized. We systematically analyze how our coarse-graining scheme resolves
dimensionless hydrodynamic numbers such as the Reynolds number, the Schmidt
number, the Mach number, the Knudsen number, and the Peclet number. The many
Brownian and hydrodynamic time-scales can be telescoped together to maximize
computational efficiency while still correctly resolving the physically
relevant physical processes. We also show how to control a number of numerical
artifacts, such as finite size effects and solvent induced attractive depletion
interactions. When all these considerations are properly taken into account,
the measured colloidal velocity auto-correlation functions and related self
diffusion and friction coefficients compare quantitatively with theoretical
calculations. By contrast, these calculations demonstrate that, notwithstanding
its seductive simplicity, the basic Langevin equation does a remarkably poor
job of capturing the decay rate of the velocity auto-correlation function in
the colloidal regime, strongly underestimating it at short times and strongly
overestimating it at long times. Finally, we discuss in detail how to map the
parameters of our method onto physical systems, and from this extract more
general lessons that may be relevant for other coarse-graining schemes such as
Lattice Boltzmann or Dissipative Particle Dynamics.Comment: 31 pages, 14 figure
Analysis of risk factors, conducted therapy and dynamics of morbidity of hemorrhagic and ischemic insult
Based on the analysis of the data of the official protocol on the number of hemorrhagic and ischemic insults in the neurological department of the city clinical hospital number 2 of Perm for 2017 and 2018, a study was conducted of the main risk factors for insult and the correlation between insults and the resulting therapy.На основании анализа данных официального протокола по количеству геморрагических и ишемических инсультов в неврологическом отделении ГКБ № 2 г. Перми за 2017 и 2018 годы, проведено исследование основных факторов риска инсультов и взаимосвязь инсультов и получаемой терапии
Non-alcoholic fatty liver disease in patients with hypertension
To study the relationship of nonalcoholic fatty liver disease (NAFLD) in patients with hypertension (AH) with cardiometabolic risk factors (FR) of cardiovascular disease (CVD) and the effect of NAFLD on their development. 71 patients with stage I-III hypertension were randomly selected for this purpose. Two groups were identified - 37 patients with NAFLD and 34 patients without NAFLD, mainly elderly and senile age. The results of the study can be concluded. The presence of NAFLD in patients with hypertension in the elderly and senile age is not sufficient for patients to be considered as patients with a higher risk of cardiovascular disease. The main reason is the presence of metabolic syndrome and its components, which increase the risk of CVD in the study group, rather than NAFLD itself. Metabolic syndrome, in our opinion, is a common denominator, the Foundation for all risk factors. The level of transaminases in the group of patients with hypertension and NAFLD decreases with age, so it is inappropriate to use ALT as a NAFLD surrogate in elderly and senile patients. The level of transaminases in patients with steatosis and steatohepatitis is not associated with the risk of cardiovascular disease. With the combination of AH and NAFLD there is no connection of NAFLD with ischemic heart disease, AF, LVH and stroke. The presence of hypertension in a patient with NAFLD and without NAFLD, in our opinion, levels the impact of NAFLD on the risk of CVD, as the hypertension itself is a powerful risk factor for cardiovascular disease. There are no differences in the frequency of LVH and in the type of LV remodeling in patients with and without NAFLD.Изучить взаимосвязь неалкогольной жировой болезни печени (НАЖБП) у больных артериальной гипертензией (АГ) с кардиометаболическими факторами риска (ФР) сердечно-сосудистых заболеваний (ССЗ) и влияние НАЖБП на их развитие. для этого методом случайной выборки выбран 71 пациент с артериальной гипертензией I-III стадией (ВОЗ). Выделено две группы - 37 пациентов с НАЖБП и 34 пациента без НАЖБП преимущественно пожилого и старческого возраста. По результатам исследования можно сделать заключение. Наличие НАЖБП у больных с АГ пожилого и старческого возраста недостаточно для того, чтобы пациенты рассматривались как больные с более высоким риском сердечно-сосудистых заболеваний. основная причина - это наличие метаболического синдрома (МС) и его компонентов, которые повышают риск ССЗ в исследуемой группе, а не сама НАЖБП. Метаболический синдром, по нашему мнению, является общим знаменателем, фундаментом для всех факторов риска. Уровень трансаминаз в группе больных с АГ и НАЖБП с возрастом снижается, поэтому использовать АЛТ в качестве суррогата НАЖБП у больных пожилого и старческого возраста неуместно. Уровень трансаминаз у больных со стеатозом и стеатогепатитом не связан с риском сердечно-сосудистых заболеваний. При сочетании АГ и НАЖБП отсутствует связь НАЖБП с ИБС, ФП, ГЛЖ и перенесенным инсультом. Наличие АГ у пациента с НАЖБП и без НАЖБП, по нашему мнению, нивелирует влияние НАЖБП на риск ССЗ, так как сама АГ является мощным фактором риска сердечно-сосудистых заболеваний. По частоте ГЛЖ и по типу ремоделирования ЛЖ различия у больных с НАЖБП и без НАЖБП отсутствуют
Updating the knowledge of hepatitis E: new variants and higher prevalence of anti-HEV in Argentina
Fil: Munné, María Silvina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Fil: Altabert, Nancy. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Fil: Otegui, Lucio. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Fil: Vladimirsky, Sara. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Fil: Moreiro, Rita. Laboratory. Pediatric Hospital J.P. Garrahan. Ciudad Autónoma de Buenos Aires; Argentina.Fil: Espul, María P. Veterinary Science Faculty. Juan Mazza University. Mendoza; Argentina.Fil: Espul, Carlos. Virology Division. Central Hospital. Mendoza; Argentina.Fil: Manzur, Abelardo. Virology Division. Central Hospital. Mendoza; Argentina.Fil: Soto, Sonia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Fil: Brajterman, Leonardo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Fil: González, Jorge E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología; Argentina.Hepatitis E is a disease of global distribution, with significant morbidity and mortality, whose scope and burden continue to emerge in low endemic countries
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