Pleiotropic effects of niacin: Current possibilities for its clinical use

Niacin was the first hypolipidemic drug to significantly reduce both major cardiovascular events and mortality in patients with cardiovascular disease. Niacin favorably influences all lipoprotein classes, including lipoproteina,and belongs to the most potent hypolipidemic drugs for increasing HDL-C. Moreover, niacin causes favorable changes to the qualitative composition of lipoprotein HDL. In addition to its pronounced hypolipidemic action, niacin exerts many other, non-hypolipidemic effects (e.g., antioxidative, anti-inflammatory, antithrombotic), which favorably influence the development and progression of atherosclerosis. These effects are dependent on activation of the specific receptor HCA2. Recent results published by the two large clinical studies, AIM-HIGH and HPS2-THRIVE, have led to the impugnation of niacin’s role in future clinical practice. However, due to several methodological flaws in the AIM-HIGH and HPS2-THRIVE studies, the pleiotropic effects of niacin now deserve thorough evaluation. This review summarizes the present and possible future use of niacin in clinical practice in light of its newly recognized pleiotropic effects

Application of methods of computational physics for the study of plasma-solid interaction

Low-temperature plasma and its interaction with immersed solids is studied in this work. The research of the physical processes on this interface is performed by two-dimensional particle computer model. The model uses molecular dynamic method. Mutual forces between particles are computed by Particle- in-Cell method. The main application of the model is in the area of the probe diagnostic of plasma. Simple problems are compared with theory and two dimensional effects are discused. Contribution of particle modeling to plasma research is showed on the problem of interaction of sheaths around cylidrical probes. We deal with question whether we are able to get some information about unevennesses at the surface of solid immersed in plasma by measuring probe characteristics in its surroundings. We also studied the influence of plasma electronegativity on the parameters of sheaths around cylidrical probes. Powered by TCPDF (www.tcpdf.org

2D & 3D computer modelling of low-temperature plasma sheaths with a particular focus on their mutual interaction

The presented thesis deals with the study of the sheath layer which is formed during the interaction of a low-temperature plasma with a solid object using computer modelling techniques. The theoretical part of the thesis summarizes knowledge about the physics of the sheath layer of electropositive and electronegative plasma and presents the theory of measuring plasma parameters using a Langmuir probe, including a discussion of the effect of collisions of charged particles with neutrals on the probe measurements. Further, theoretical descriptions of the plasma are presented which are the basis of the computer models created in the framework of the thesis: a particle model based on the Particle-in-Cell method and a fluid model of the drift-diffusion approximation of the plasma. The developed particle model works in 3D space, uses the null-collision Monte Carlo method to account for the effects of collisions of charged particles with neutrals and implements the Intel Math Kernel Library functions to solve the Poisson's equation. The fluid model is implemented using FeniCS software. At first, the developed models are used for the calculation of the sheath layer and the current-voltage characteristics of free-standing Langmuir probes of several types: a 1D model of an infinitely large planar probe, a 2D model of..

2D & 3D počítačové modelování stínících vrstev nízkoteplotního plazmatu se zaměřením na jejich vzájemnou interakci

Předložená práce se zabývá studiem stínící vrstvy, která vzniká při interakci nízkoteplotního plazmatu s pevnou látkou, pomocí techniky počítačového modelování. Teoretická část práce shrnuje poznatky o fyzice stínící vrstvy elektropozitivního i elektronegativního plazmatu a prezentuje teorii měření parametrů plazmatu pomocí Langmuirovy sondy včetně diskuze vlivu srážek nabitých částic s neutrálními na sondová měření. Dále jsou předneseny teoretické popisy plazmatu, ze kterých vycházejí počítačové modely vytvořené v rámci práce: částicový model založený na metodě Particle-in-Cell a spojitý model drift-difúzní aproximace plazmatu. Vyvinutý částicový model pracuje ve 3D prostoru, využívá Monte Carlo metodu nulové srážky pro započítání efektů srážek nabitých částic s neutrálními a implementuje funkce knihovny Intel Math Kernel Library pro řešení Poissonovy rovnice. Spojitý model byl implementován pomocí software FeniCS. Vyvinuté modely byly nejprve využity pro výpočet stínící vrstvy a voltampérových charakteristik samostatně stojících Langmuirových sond několika typů: 1D model nekonečně rozlehlé rovinné sondy, 2D model válcové sondy a 3D model rovinné sondy konečných rozměrů. Výpočty byly úspěšně srovnány s teorií a diskutovány byly vzájemné rozdíly při užití různých modelovacích technik. Pozornost byla dále...The presented thesis deals with the study of the sheath layer which is formed during the interaction of a low-temperature plasma with a solid object using computer modelling techniques. The theoretical part of the thesis summarizes knowledge about the physics of the sheath layer of electropositive and electronegative plasma and presents the theory of measuring plasma parameters using a Langmuir probe, including a discussion of the effect of collisions of charged particles with neutrals on the probe measurements. Further, theoretical descriptions of the plasma are presented which are the basis of the computer models created in the framework of the thesis: a particle model based on the Particle-in-Cell method and a fluid model of the drift-diffusion approximation of the plasma. The developed particle model works in 3D space, uses the null-collision Monte Carlo method to account for the effects of collisions of charged particles with neutrals and implements the Intel Math Kernel Library functions to solve the Poisson's equation. The fluid model is implemented using FeniCS software. At first, the developed models are used for the calculation of the sheath layer and the current-voltage characteristics of free-standing Langmuir probes of several types: a 1D model of an infinitely large planar probe, a 2D model of...Katedra fyziky povrchů a plazmatuDepartment of Surface and Plasma ScienceMatematicko-fyzikální fakultaFaculty of Mathematics and Physic

Modeling of seismic wave propagation in random medium and its influence on source directivity

Department of GeophysicsKatedra geofyzikyFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

2D & 3D computer modelling of low-temperature plasma sheaths with a particular focus on their mutual interaction

The presented thesis deals with the study of the sheath layer which is formed during the interaction of a low-temperature plasma with a solid object using computer modelling techniques. The theoretical part of the thesis summarizes knowledge about the physics of the sheath layer of electropositive and electronegative plasma and presents the theory of measuring plasma parameters using a Langmuir probe, including a discussion of the effect of collisions of charged particles with neutrals on the probe measurements. Further, theoretical descriptions of the plasma are presented which are the basis of the computer models created in the framework of the thesis: a particle model based on the Particle-in-Cell method and a fluid model of the drift-diffusion approximation of the plasma. The developed particle model works in 3D space, uses the null-collision Monte Carlo method to account for the effects of collisions of charged particles with neutrals and implements the Intel Math Kernel Library functions to solve the Poisson's equation. The fluid model is implemented using FeniCS software. At first, the developed models are used for the calculation of the sheath layer and the current-voltage characteristics of free-standing Langmuir probes of several types: a 1D model of an infinitely large planar probe, a 2D model of..

Application of methods of computational physics for the study of plasma-solid interaction

Low-temperature plasma and its interaction with immersed solids is studied in this work. The research of the physical processes on this interface is performed by two-dimensional particle computer model. The model uses molecular dynamic method. Mutual forces between particles are computed by Particle- in-Cell method. The main application of the model is in the area of the probe diagnostic of plasma. Simple problems are compared with theory and two dimensional effects are discused. Contribution of particle modeling to plasma research is showed on the problem of interaction of sheaths around cylidrical probes. We deal with question whether we are able to get some information about unevennesses at the surface of solid immersed in plasma by measuring probe characteristics in its surroundings. We also studied the influence of plasma electronegativity on the parameters of sheaths around cylidrical probes. Powered by TCPDF (www.tcpdf.org

Computer Simulation of Metal Ions Transport to Uneven Substrates during Ionized Plasma Vapour Deposition

We present a computational study of processes taking place in a sheath region formed near a negatively biased uneven substrate during ionized plasma vapour deposition. The sputtered metal atoms are ionized on their way to substrate and they are accelerated in the sheath near the substrate. They are able to penetrate to high-aspect-ratio structures, for example, trenches, which can be, therefore, effectively coated. The main technique used was a two-dimensional particle simulation. The results of our model predict the energy and angular distributions of impinging ions in low-pressure conditions which are characteristic for this method and where typical continuous models fail due to unfulfilled assumptions. Input bulk plasma properties were computed by a “zero dimensional” global model which took into account more physical processes important on a scale of the whole magnetron chamber. Output parameters, such as electrostatic potential, energy of ions, and ion fluxes, were computed for wide range of conditions (electron density and substrate bias) to show the influence of these conditions on observed phenomena, penetration of sheath inside the trench, deceleration of argon and copper ions inside the trench, and local maxima of ion fluxes near the trench opening