8 research outputs found
Self-diffusion in strongly coupled Yukawa systems (complex plasmas)
We show that the idea of mapping between the Newtonian and Brownian
diffusivities proposed and tested on a class of particle systems interacting
via soft and ultra-soft potentials (IPL, Gaussian core, Hertzian, and effective
star-polymer) by Pond {\it et al}., [Soft Matter {\bf 7}, 9859 (2011)] is also
applicable to the Yukawa (screened Coulomb) interaction. Some of the
implications of this result with respect to self-diffusion in strongly coupled
complex (dusty) plasmas are discussed.Comment: 9 pages, 3 figures, submitted to Phys. Plasma
Self-diffusion in strongly coupled Yukawa systems (complex plasmas)
We show that the idea of mapping between the Newtonian and Brownian
diffusivities proposed and tested on a class of particle systems interacting
via soft and ultra-soft potentials (IPL, Gaussian core, Hertzian, and effective
star-polymer) by Pond {\it et al}., [Soft Matter {\bf 7}, 9859 (2011)] is also
applicable to the Yukawa (screened Coulomb) interaction. Some of the
implications of this result with respect to self-diffusion in strongly coupled
complex (dusty) plasmas are discussed.Comment: 9 pages, 3 figures, submitted to Phys. Plasma
Stochastic motion of grains with charge gradients in external electric fields
We consider a theoretical model describing the “anomalous heating” of charged grains due to their stochastic motion in the volume of a spatially inhomogeneous plasma. On the basis of this model for the first time we propose the analytical relations for conditions of the heating of grains due to the gradient of their charge in the electric field of a trap. The obtained relations were tested by numerical simulations of the problem for one and two charged particles
Formation of layered structures of particles with anisotropic pair interaction
The results of the numerical investigation of a layered structure formation in systems of particles with anisotropic pair interaction are presented. A simulation was carried out for extended homogeneous structures consisting of one or several layers of interacting particles over a wide range of parameters which correspond to the conditions usually observed in laboratory dusty plasma experiments. For the first time a detailed analysis of the development of various instabilities in such systems has been undertaken
Kinetic energy in a system of particles with a nonreciprocal interaction
We present a theoretical model for the description of the heating mechanism and the redistribution of kinetic energy in a system of particles with nonreciprocal interactions that occur in disperse systems of different nature. To verify the theory, we carried out the numerical simulations of two-particle systems with a nonreciprocal “quasi-dipole–dipole” interaction that is similar to the interaction due to the effect of ion focusing in a laboratory complex plasma under experimental conditions. The proposed model of heating can explain various features of dust dynamics in anisotropic complex plasma
Sympathetic Denervation and Pharmacological Stimulation of Parasympathetic Nervous System Prevent Pulmonary Vascular Bed Remodeling in Rat Model of Chronic Thromboembolic Pulmonary Hypertension
Chronic thromboembolic pulmonary hypertension (CTEPH) develops in 1.5–2.0% of patients experiencing pulmonary embolism (PE) and is characterized by stable pulmonary artery obstruction, heart failure, and poor prognosis. Little is known about involvement of autonomic nervous system (ANS) in the mechanisms of CTEPH. This study was aimed at evaluation of the effect of vagal and sympathetic denervation, as well as stimulation of the parasympathetic nervous system, on the outcomes of CTEPH in rats. CTEPH was induced by multiple intravenous injections of alginate microspheres. Sympathetic and vagal denervation was performed using unilateral surgical ablation of the stellate ganglion and vagotomy, respectively. Stimulation of the parasympathetic nervous system was carried out by administering pyridostigmine. The effect of neuromodulatory effects was assessed in terms of hemodynamics, histology, and gene expression. The results demonstrated the key role of ANS in the development of CTEPH. Sympathetic denervation as well as parasympathetic stimulation resulted in attenuated pulmonary vascular remodeling. These salutary changes were associated with altered MMP2 and TIMP1 expression in the lung and decreased FGFb level in the blood. Unilateral vagotomy had no effect on physiological and morphological outcomes of the study. The data obtained contribute to the identification of new therapeutic targets for CTEPH treatment
Sympathetic Denervation and Pharmacological Stimulation of Parasympathetic Nervous System Prevent Pulmonary Vascular Bed Remodeling in Rat Model of Chronic Thromboembolic Pulmonary Hypertension
Chronic thromboembolic pulmonary hypertension (CTEPH) develops in 1.5–2.0% of patients experiencing pulmonary embolism (PE) and is characterized by stable pulmonary artery obstruction, heart failure, and poor prognosis. Little is known about involvement of autonomic nervous system (ANS) in the mechanisms of CTEPH. This study was aimed at evaluation of the effect of vagal and sympathetic denervation, as well as stimulation of the parasympathetic nervous system, on the outcomes of CTEPH in rats. CTEPH was induced by multiple intravenous injections of alginate microspheres. Sympathetic and vagal denervation was performed using unilateral surgical ablation of the stellate ganglion and vagotomy, respectively. Stimulation of the parasympathetic nervous system was carried out by administering pyridostigmine. The effect of neuromodulatory effects was assessed in terms of hemodynamics, histology, and gene expression. The results demonstrated the key role of ANS in the development of CTEPH. Sympathetic denervation as well as parasympathetic stimulation resulted in attenuated pulmonary vascular remodeling. These salutary changes were associated with altered MMP2 and TIMP1 expression in the lung and decreased FGFb level in the blood. Unilateral vagotomy had no effect on physiological and morphological outcomes of the study. The data obtained contribute to the identification of new therapeutic targets for CTEPH treatment
Inhibition of JAK1,2 Prevents Fibrotic Remodeling of Pulmonary Vascular Bed and Improves Outcomes in the Rat Model of Chronic Thromboembolic Pulmonary Hypertension
Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism with poor clinical outcomes. Therapeutic approaches to prevention of fibrotic remodeling of the pulmonary vascular bed in CTEPH are limited. In this work, we tested the hypothesis that Janus kinase 1/2 (JAK1/2) inhibition with ruxolitinib might prevent and attenuate CTEPH in a rat model. CTEPH was induced by repeated embolization of the pulmonary artery with partially biodegradable 180 ± 30 μm alginate microspheres. Two weeks after the last injection of microspheres, ruxolitinib was administered orally at doses of 0.86, 2.58, and 4.28 mg/kg per day for 4 weeks. Prednisolone (1.475 mg/kg, i.m.) was used as a reference drug. Ruxolitinib in all doses as well as prednisolone reduced pulmonary vascular wall hypertrophy. Ruxolitinib at a dose of 2.58 mg/kg and prednisolone reduced vascular wall fibrosis. Prednisolone treatment resulted in decreased right ventricular systolic pressure. Pulmonary vascular resistance was lower in the prednisolone and ruxolitinib (4.28 mg/kg) groups in comparison with the placebo group. The plasma level of brain natriuretic peptide was lower in groups receiving ruxolitinib at doses of 2.58 and 4.28 mg/kg versus placebo. This study demonstrated that JAK1/2 inhibitor ruxolitinib dose-dependently reduced pulmonary vascular remodeling, thereby preventing CTEPH formation in rats