105 research outputs found
Effect of magnetic field on the velocity autocorrelation and the caging of particles in two-dimensional Yukawa liquids
We investigate the effect of an external magnetic field on the velocity
autocorrelation function and the "caging" of the particles in a two-dimensional
strongly coupled Yukawa liquid, via numerical simulations. The influence of the
coupling strength on the position of the dominant peak in the frequency
spectrum of the velocity autocorrelation function confirms the onset of a joint
effect of the magnetic field and strong correlations at high coupling. Our
molecular dynamics simulations quantify the decorrelation of the particles'
surroundings - the magnetic field is found to increase significantly the caging
time, which reaches values well beyond the timescale of plasma oscillations.
The observation of the increased caging time is in accordance with findings
that the magnetic field decreases diffusion in similar systems
Influence of the ion core on relaxation processes in dense plasmas
The effect of an ionic core on the temperature relaxation in dense hot plasma
of beryllium is studied using the pseudpotential model by Gericke et al [Phys.
Rev. E 2010, 81, 065401(R)]. Employing the screened version of the ion
pseudpotential [by Ramazanov et al, Phys. Plasmas 2021, 28 (9), 092702], we
computed the quantum transport cross-section for the electron-ion collisions in
dense beryllium plamsas, where screening is taking into account using the
density response function in the long wavelength regime. The results for the
transport cross-section are used to compute a generalised Coulomb logarithm and
electron-ion collision frequency. Utilizing the latter, we show the effect of
the ionic core on the temperature relaxation. To understand the role of the
ionic core, we compare the results with the data computed considering ions as
point-like charges
Осмотический демиелинизирующий синдром
ABSTRACT. This article discusses the clinical cases of rare and difficult to diagnose brain damage — osmotic demyelinating syndrome (ODS). ODS is a lifethreatening condition, manifested by acute demyelination of the headbrain on the background of water-electrolyte disturbances,usually associated with fast management of hyponatremia. Within the framework of ODS, central pontine myelinolysis (CPM) and extra-pontine myelinolysis (EPM) are observed, which are accompanied by acute demyelination in the pons and white matter of the cerebral hemispheres, respectively. In 60%, CPM combine with EPM. The main reason for the development of ODS is a violation of water-electrolyte metabolism associated with alcohol abuse, chronic hepatic and/or renal failure, diabetes mellitus, Sheehan syndrome, polydipsia, condition after the removal of pituitary adenoma, bulimia, immunodeficiency syndrome. Today, the diagnosis of ODS is based on magnetic resonance imaging of the brain. The article indicates the main causes of the disease, clinical features, methods of diagnosis and treatment, as well as the outcomes of the disease.РЕЗЮМЕ. Данная статья посвящена обсуждению клинических случаев редкого и трудно диагностируемого поражения головного мозга — осмотического демиелинизирующего синдрома (ОДС). ОДС — жизнеугрожающее состояние, проявляющееся остро возникающей демиелинизацией головного мозга на фоне водно-электролитных нарушений, как правило, связанных с быстрой коррекцией гипонатриемии. В рамках ОДС выделяют центральный понтинный миелинолиз (ЦПМ) и экстрапонтинный миелинолиз (ЭПМ), которые сопровождаются острой демиелинизацией в области моста и белого вещества больших полушарий головного мозга соответственно. В 60% ОДС сочетает в себе ЦПМ и ЭПМ. Основная причина развития ОДС — нарушения водно-электролитного обмена, возникающие на фоне злоупотребления алкоголем, хронической печеночной и/или почечной недостаточности, сахарного диабета, синдрома Шихана, полидипсии, состояния после удаления аденомы гипофиза, булимии, синдрома иммунодефицита. В настоящее время диагнос- тика ОДС основана на данных магнитно-резонансной томографии головного мозга. В статье ука- заны основные причины заболевания, клинические особенности, методы диагностики и лечения, а также исходы заболевания
Dynamical correlations and collective excitations of Yukawa liquids
In dusty (complex) plasmas, containing mesoscopic charged grains, the
grain-grain interaction in many cases can be well described through a Yukawa
potential. In this Review we summarize the basics of the computational and
theoretical approaches capable of describing many-particle Yukawa systems in
the liquid and solid phases and discuss the properties of the dynamical density
and current correlation spectra of three- and two-dimensional strongly coupled
Yukawa systems, generated by molecular dynamics simulations. We show details of
the dispersion relations for the collective excitations in these
systems, as obtained theoretically following the quasilocalized charge
approximation, as well as from the fluctuation spectra created by simulations.
The theoretical and simulation results are also compared with those obtained in
complex plasma experiments.Comment: 54 pages, 31 figure
ИНФАРКТ ГОЛОВНОГО МОЗГА КАК ПЕРВОЕ ПРОЯВЛЕНИЕ ЭРИТРЕМИИ
The article reports a clinical case of the stroke on the background of newly diagnosed polycythemia vera. Possible mechanisms of the stroke in the course of erythremia as well ascurrent methods oftreatment for the disease are described.В статье представлен клинический случай развития инсульта на фоне впервые выявленной истинной полицитемии. Рассмотрены возможные механизмы развития инсульта при эритремии. Представлены современные методы лечения данной патологии
Supplement with Cystoseira canariensis promotes an increase of resistance to the maximum load in the grastrocnemius muscle of female rats
Was evaluated the maximum load supported by the grastrocnemius muscle of female rats after the ministering of Cystoseira canariensis, either associated or not to swimming. Twenty-eight young Wistar female rats were used, divided into 4 groups: control (C, n=7); supplement (S, n=7); supplement and swimming (SSw, n=7); swimming (Sw, n=7). Each one pertaining to the groups S and SSw received 20 mg of myostatin inhibitor per day. The swimming consisted in an aerobe protocol, three times in a week, during eight weeks. The right grastrocnemius muscle of each animal was removed and a tension test was performed in an Emic testing machine. The results (Mean±SEM) were evaluated through ANOVA and Tukey test (p<0.05). A significant difference for maximum load (in N) was verified among the groups C (35.41±1.06) and S (39.98±1.15); Sw (27.94±2.19) and S (39.98±1.15); Sw (27.94±2.19) and SSw (37.78±1.28). In relation to the stretching at the maximum limit (in x10-3m) at the maximum load, the group SSw obtained a value (20.68±1.19) significantly greater than the groups C (17.15±1.11), S and Sw (16.11±1.60). There was a significant difference for body weight gain among the groups treated with supplement and supplement associated to the swimming, with smaller values for this last. The myostatin inhibitor either, associated or not to the swimming, promotes an increase of resistance to the maximum load in the tension test in grastrocnemius muscle of young female rats
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