152 research outputs found
Multikomponentní plazmové polymery s prostorově řízenými vlastnostmi
Get PDFTitle: Multicomponent plasma polymers with spatially controlled properties Author: MSc. Pavel Pleskunov Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Prof. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics / Charles University Abstract: Mixing of two (or more) polymers often leads to phase separation and to the formation of nanoscale architecture, which can be highly attractive in various applications including controllable drug delivery, fabrication of separation and solid electrolyte membranes, gas storage, etc. Different wet-chemistry techniques already exist to produce nanophase-separated polymers; however, capturing the resultant polymeric structure in a predictable manner remains a challenging task. In this thesis, a low-temperature plasma-based strategy is investigated for the production of multicomponent thin films of plasma polymers with spatially discriminated nanoscale domains. Gas aggregation cluster source is used for the fabrication of nanoparticles of plasma polymerized acrylic acid, whereas Plasma-Assisted Vapor Phase Deposition is used for the deposition of thin films of poly(ethylene oxide) plasma polymer. Embedding of nanoparticles into matrices of thermodynamically incompatible plasma polymer as well as...Název práce: Multikomponentní plazmové polymery s prostorově řízenými vlastnostmi Author: Mgr. Pavel Pleskunov Katedra/Ústav: Katedra Makromolekulární Fyziky/Univerzita Karlova Vedoucí doktorské práce: Prof. Ing. Andrey Shukurov, PhD Abstrakt: Směšování dvou či více polymerů často vede k jejich fázové separaci a ke vzniku nanostruktur, které jsou atraktivní pro využití v různých aplikacích včetně řízeného podávání léčiv, přípravy separačních membrán, membrán s pevným elektrolytem, skladování plynů atd. Ačkoliv již byly vyvinuty nejrůznější metody přípravy nanofázově separovaných polymerů, které jsou založeny na "mokré" chemii, řízení a předpověditelné ovlivňování jejich finální struktury doposud představuje obtížný vědecký problém. V předkládané disertační práci je zkoumána možnost přípravy vícesložkových tenkých vrstev plazmových polymerů s prostorově odlišitelnými nanodoménami pomocí metod založených na využití nízkoteplotního plazmatu. Nanočástice plazmových polymerů jsou připravovány pomocí plynových agregačních zdrojů, zatímco matrice plazmových polymerů (plazmově polymerizovaný polyetylénoxid) jsou nanášeny v podobě tenkých vrstev pomocí plazmatem podporované depozici z plynné fáze. Je zkoumáno zabudovávání nanočástic do termodynamicky nekompatibilního plazmového polymeru i ko- depozice dvou...Katedra makromolekulární fyzikyDepartment of Macromolecular PhysicsFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult
Shukurov, S., & Krasovsky, K. (2013). Impact of cigarette taxation policy on excise revenues and cigarette consumption in Uzbekistan
No full text<p>Shukurov, S., & Krasovsky, K. (2013). Impact of cigarette taxation policy on excise revenues and cigarette consumption in Uzbekistan. Tobacco Control and Public Health in Eastern Europe, 3(1), 5-16.</p>
<p>BACKGROUND: In 2012, Uzbekistan ratified the Framework Convention on Tobacco Control, which states that price and tax measures are an effective means of reducing tobacco consumption. We aimed to explore the effect of taxation policies on revenues and cigarette consumption.<br>METHODS: Data on tax rates, revenues, cigarette sales were taken from national reports. To forecast potential revenues, a scenario analysis was performed.<br>RESULTS: In 1991-2004, ad valorem excise system was in place in Uzbekistan, which was later replaced by the specific excise system. In 1997-2011, the nominal average excise has increased by a factor of twenty, but in real terms, after a sharp increase in 1999, average excise declined annually and increased only in 2010-2011. Annual cigarette sales per capita of adult population in 1999-2007 constituted 17-25 cigarette packs, while in 2008-2011 it increased to 30-37 packs. Four scenarios of excise tax increases in 2012 were developed: one actual scenario based on the rates effective in Uzbekistan in 2012, and three hypothetical ones anticipating excise rates increase by 1.5, 2 and 3-fold. With actual excise increase in 2012, the inflation-adjusted budget revenues would grow by 5%, and with three hypothetical - by 17%, 35% and 66% respectively, despite the decline of tax-paid cigarette sales.<br>CONCLUSION: Stabilization or reduction in cigarette excises in Uzbekistan in 2002-2008 led to a decline in real excise revenues and the growth of cigarette sales. In 1999 and 2010-2011, excises were significantly increased and the real revenues have risen, despite the decline in cigarette sales. As cigarette prices are low, the illegal outflow of cigarettes from Uzbekistan apparently exceeds the illegal inflow. A significant increase in cigarette excise (1.5-3 fold) can both increase budget revenues and reduce cigarette consumption, with greater increase yielding more benefits.</p>
<p>KEYWORDS: Uzbekistan; tobacco; excise; cigarettes; revenue.</p>
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Nanostrukturované plazmové polymery pro řízenou imobilizaci biomolekul
Get PDFNázev práce: Nanostrukturované plazmové polymery pro řízenou imobilizaci biomolekul Autor: Iurii Melnichuk Katedra/Ústav: Katedra Makromolekulární Fyziky/Univerzita Karlova Vedoucí doktorské práce: Doc. Ing. Andrey Shukurov, Ph.D. Abstrakt: V této práci studujeme možnosti aplikace nanostruktur při funkcionalizaci povrchů pro interakce s biomolekulami. V první části práce zkoumáme vznik a počáteční stadia růstu tenkých nano- strukturovaných polymerních vrstev nanášených metodou vakuové termální depozice. Růst polyethylenových (PE) ostrůvků je diskutován jak z hlediska kinetických rovnic, tak pomocí teorie dynamického škalování. Druhá část práce je věnována imobilizaci proteinů prostřednictvím kovalentního navázáni na nano- strukturované povrchy aktivované bariérovým výbojem. Diskutujeme jak ovlivňuje morfologie povrchu a přítomnost tropoelastinu proces přežívání buněk na takových površích. Ultra-tenké hydrokarbonové vrstvy schopné imobilizace proteinů jsou vytvořeny metodou plazmové polymerace. Mezi hlavní výsledky práce patří stanovení kritického rozměru ostrůvků a objasnění průběhu nukleace v počáteční fázi jejich růstu. Ošetření PE nanostruktur atmosférickým nízko-teplotním plazmatem vede k jednoduché a účinné kovalentní imobilizaci proteinů na povrchu. Chování buněk na takových površích je závislé na...Title: Nano-structured multicomponent plasma polymers for controlled immobilization of biomolecules Author: Iurii Melnichuk Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, Ph.D. Abstract: The aim of this thesis is to highlight the feasibility of tailored nano- structures in functionalizing surfaces for biointerfacial interactions. Development of new techniques for the production of nanoscaled biomaterials can be of use in a variety of medical and biological applications, e.g. biosensors, microarrays, drug sensors, implants, blood-contacting devices. This thesis first examines the early stages of nano-structured thin film growth fabricated by vapor phase deposition of poly(ethylene). We discuss island growth within a framework of rate equation theory, dynamic scaling theory and capture zone distribution. In a second stage, we test dielectric barrier discharge to activate PE nano-pattern for covalent immobilization of proteins. Finally, we assess cell behavior on surfaces in dependence on morphology and the presence of cell adhesive protein tropoelastin. We employ plasma polymerization to produce ultrathin hydrocarbon layer capable of protein anchoring. The thesis findings for the first time manifest the critical...Katedra makromolekulární fyzikyDepartment of Macromolecular PhysicsMatematicko-fyzikální fakultaFaculty of Mathematics and Physic
Příprava tenkých vrstev plazmovou polymerací jako stabilních podložek pro biolékařské aplikace
Get PDFTitle: Thin films of plasma polymers as stable supports for biomedical applications Author: Ivan Gordeev Institute: Charles University in Prague, Department of Macromolecular Physics Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, Ph.D, Charles University in Prague, Department of Macromolecular Physics. Abstract: Plasma polymers have been widely considered for use as bio-active coatings. In biomedicine, the surfaces that withstand accumulation of biofilms are of particular importance. This thesis is focused on development of new plasma-based methods for deposition of bio-resistant (non-fouling) plasma polymers. Poly(ethylene oxide) was the subject material. R.f. magnetron sputtering, plasma-assisted thermal vapour deposition and amplitude modulated atmospheric pressure surface dielectric barrier discharge were the methods adapted to fabricate thin films with tunable chemical composition, cross-link density and biological response. A new insight was gained into the processes of plasma polymerization as well as into composition/structure relationship and its effect on biological properties of resultant films. Keywords: plasma polymerization, PEO, 'non-fouling' properties, protein adsorption, cell adhesionNázev práce: Příprava tenkých vrstev plazmovou polymerací jako stabilních podložek pro biolékařské aplikace Autor: Ivan Gordeev Ústav: Univerzita Karlova v Praze, Katedra Makromolekulární Fyziky Vedoucí doktorské práce: Doc. Ing. Andrey Shukurov, Ph.D., Univerzita Karlova v Praze, Katedra Makromolekulární Fyziky Abstrakt: Plazmové polymery jsou všeobecně považovány za vhodné pro použití jako biologicky aktivní vrstvy. V biomedicíně jsou obzvláště důležité povrchy, které odolávají vytváření biovrstev. Tato práce je zaměřena na vývoj nových metod využívajících plazma pro depozice bio-rezistentních ("non-fouling") plazmových polymerů. Pro tyto účely byl vybrán jako vhodný materiál poly(ethylen oxid) (PEO). R.f. magnetronové naprašování, tepelná depozice za asistence plazmatu a amplitudově-modulovaný AC povrchový dielektrický bariérový výboj za atmosférického tlaku jsou metody, které byly přizpůsobeny pro přípravu tenkých filmů s laditelným chemickým složením, hustotou sesíťování a laditelnou biologickou odezvou. Byly získány nové poznatky o procesech plazmové polymerace a jejich vlivu na složení a strukturu výsledných vrstev s řízenými biologickými vlastnostmi. Klíčová slova: plazmová polymerizace, PEO, "non-fouling" vlastnosti, adsorpce proteinů, adheze buněkKatedra makromolekulární fyzikyDepartment of Macromolecular PhysicsFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult
Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films
No full textTitle: Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films Author: Daniil Nikitin Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics/Charles University Abstract: The PhD thesis aims at the investigation of nanostructures based on plasma polymers. The main attention is paid to the combination of a gas aggregation cluster source with plasma-assisted vapor phase deposition for the fabrication of metal-polymer nanocomposites with bactericidal potential. Copper nanoparticles were incorporated into a biocompatible matrix of plasma polymerized poly(ethylene oxide) (ppPEO). The efficiency of such nanocomposite against multi-drug resistant bacteria was demonstrated. It was found that the segmental dynamics of the plasma polymer significantly changed in the presence of nanoparticles as revealed by the measurements of the dynamic glass transition temperature. The nanoscale confinement crucially influences the non-fouling properties of poly(ethylene oxide). A separate chapter is dedicated to the examination of the nanoparticle formation, growth and transport inside the source. Copper and silver nanoparticles were detected in situ in the gas phase..
Strukturování plazmových polymerů: nové metody přípravy tenkých vrstev s nano-architekturou
Get PDFNázev práce: Strukturování plazmových polymerů: nové metody přípravy tenkých vrstev s nano-architekturou Autor: Daniil Nikitin Katedra/Ústav: Katedra Makromolekulární Fyziky/Univerzita Karlova Vedoucí doktorské práce: Doc. Ing. Andrey Shukurov, PhD Abstrakt: Disertační práce je zaměřena na studium nanostruktur na bázi plazmových polymerů. Hlavní pozornost je věnována přípravě antibakteriálních nanokompozitních vrstev kov/polymer za použití plynového agregačního zdroje nanočástic a plazmatem asistované depozice z plynné fáze. Do biokompatibilní matrice plazmového polymeru poly(ethylen oxidu) (ppPEO) byly začleněny měděné nanočástice. Byla prokázána účinnost těchto nanokompozitů proti multi-rezistentním bakteriím. Pomocí měření dynamické teploty skelného přechodu bylo zjištěno, že se v přítomnosti nanočástic významně změnila segmentová dynamika plazmového polymeru. To zásadně ovlivnilo bio-rezistentní vlastnosti poly(ethylen oxidu). Samostatná kapitola je věnována studiu vzniku, růstu a transportu nanočástic uvnitř zdroje. Měděné a stříbrné nanočástice byly detekovány in situ v plynné fázi buďto pomocí maloúhlového rozptylu rentgenového záření, nebo pomocí UV-Vis spektroskopie. Vůbec poprvé bylo zjištěno zachytávání kovových nanočástic v plazmatu. Navíc byla potvrzena částečná re-depozice nanočástic na terč a...Title: Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films Author: Daniil Nikitin Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics/Charles University Abstract: The PhD thesis aims at the investigation of nanostructures based on plasma polymers. The main attention is paid to the combination of a gas aggregation cluster source with plasma-assisted vapor phase deposition for the fabrication of metal-polymer nanocomposites with bactericidal potential. Copper nanoparticles were incorporated into a biocompatible matrix of plasma polymerized poly(ethylene oxide) (ppPEO). The efficiency of such nanocomposite against multi-drug resistant bacteria was demonstrated. It was found that the segmental dynamics of the plasma polymer significantly changed in the presence of nanoparticles as revealed by the measurements of the dynamic glass transition temperature. The nanoscale confinement crucially influences the non-fouling properties of poly(ethylene oxide). A separate chapter is dedicated to the examination of the nanoparticle formation, growth and transport inside the source. Copper and silver nanoparticles were detected in situ in the gas phase...Katedra makromolekulární fyzikyDepartment of Macromolecular PhysicsMatematicko-fyzikální fakultaFaculty of Mathematics and Physic
Multicomponent plasma polymers with spatially controlled properties
No full textTitle: Multicomponent plasma polymers with spatially controlled properties Author: MSc. Pavel Pleskunov Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Prof. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics / Charles University Abstract: Mixing of two (or more) polymers often leads to phase separation and to the formation of nanoscale architecture, which can be highly attractive in various applications including controllable drug delivery, fabrication of separation and solid electrolyte membranes, gas storage, etc. Different wet-chemistry techniques already exist to produce nanophase-separated polymers; however, capturing the resultant polymeric structure in a predictable manner remains a challenging task. In this thesis, a low-temperature plasma-based strategy is investigated for the production of multicomponent thin films of plasma polymers with spatially discriminated nanoscale domains. Gas aggregation cluster source is used for the fabrication of nanoparticles of plasma polymerized acrylic acid, whereas Plasma-Assisted Vapor Phase Deposition is used for the deposition of thin films of poly(ethylene oxide) plasma polymer. Embedding of nanoparticles into matrices of thermodynamically incompatible plasma polymer as well as..
Nano-structured multicomponent plasma polymers for controlled immobilization of biomolecules
No full textTitle: Nano-structured multicomponent plasma polymers for controlled immobilization of biomolecules Author: Iurii Melnichuk Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, Ph.D. Abstract: The aim of this thesis is to highlight the feasibility of tailored nano- structures in functionalizing surfaces for biointerfacial interactions. Development of new techniques for the production of nanoscaled biomaterials can be of use in a variety of medical and biological applications, e.g. biosensors, microarrays, drug sensors, implants, blood-contacting devices. This thesis first examines the early stages of nano-structured thin film growth fabricated by vapor phase deposition of poly(ethylene). We discuss island growth within a framework of rate equation theory, dynamic scaling theory and capture zone distribution. In a second stage, we test dielectric barrier discharge to activate PE nano-pattern for covalent immobilization of proteins. Finally, we assess cell behavior on surfaces in dependence on morphology and the presence of cell adhesive protein tropoelastin. We employ plasma polymerization to produce ultrathin hydrocarbon layer capable of protein anchoring. The thesis findings for the first time manifest the critical..
Thin films of plasma polymers as stable supports for biomedical applications
No full textTitle: Thin films of plasma polymers as stable supports for biomedical applications Author: Ivan Gordeev Institute: Charles University in Prague, Department of Macromolecular Physics Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, Ph.D, Charles University in Prague, Department of Macromolecular Physics. Abstract: Plasma polymers have been widely considered for use as bio-active coatings. In biomedicine, the surfaces that withstand accumulation of biofilms are of particular importance. This thesis is focused on development of new plasma-based methods for deposition of bio-resistant (non-fouling) plasma polymers. Poly(ethylene oxide) was the subject material. R.f. magnetron sputtering, plasma-assisted thermal vapour deposition and amplitude modulated atmospheric pressure surface dielectric barrier discharge were the methods adapted to fabricate thin films with tunable chemical composition, cross-link density and biological response. A new insight was gained into the processes of plasma polymerization as well as into composition/structure relationship and its effect on biological properties of resultant films. Keywords: plasma polymerization, PEO, 'non-fouling' properties, protein adsorption, cell adhesio
Water quality and dissolved load in the Chirchik and Akhangaran river basins (Uzbekistan, Central Asia)
Get PDFUzbekistan (Central Asia) is experiencing serious water stress as a consequence of altered climate regime, past over-exploitation, and dependence from neighboring countries for water supply. The Chirchik-Akhangaran drainage basin, in the Tashkent province of Uzbekistan, includes watersheds from the Middle Tien Shan Mountains escarpments and the downstream floodplain of the Chirchik and Akhangaran rivers, major tributaries of the Syrdarya river. Water in the Chirchik-Akhangaran basin is facing potential anthropogenic pressure from different sources at the scale of river reaches, from both industrial and agricultural activities. In this study, the major and trace element chemistry of surface water and groundwater from the Chirchik-Akhangaran basin were investigated, with the aim of addressing the geogenic and anthropogenic contributions to the dissolved load. The results indicate that the geochemistry of water from the upstream catchments reflects the weathering of exposed lithologies. A significant increase in Na+, K+, SO42-, Cl-, and NO3- was observed downstream, indicating loadings from fertilizers used in croplands. However, quality parameters suggest that waters are generally suitable for irrigation purposes, even if the total dissolved solid indicates a possible salinity hazard. The concentration of trace elements (including potentially toxic elements) was lower than the thresholds set for water quality by different regulations. However, an exceedingly high concentration of Zn, Mo, Sb, Pb, Ni, U, As, and B compared with the average river water worldwide was observed. Water in a coal fly-ash large pond related to the Angren coal-fired power plants stands out for the high As, Al, B, Mo, and Sb concentration, having a groundwater contamination potential during infiltration. Spring waters used for drinking purposes meet the World Health Organization and the Republic of Uzbekistan quality standards. However, a surveillance of such drinking-water supplies is suggested. The obtained results are indicators for an improved water resource management
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