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We consider closed orientable surfaces S of genus greater than one and homeomorphisms f homotopic to the identity. A set of hypotheses is presented, called fully essential system of curves, and it is shown that under these hypotheses, the natural lift of f to the universal cover of S (the Poincaré disk), has complicated and rich dynamics. We also show that the homological rotation set of such a f is a compact convex set with maximal dimension and all points in its interior are realized by compact f-invariant sets, periodic orbits in the rational case. / Consideramos superfícies fechadas orientáveis S de gênero maior do que um e homeomorfismos f homotópicos a identidade. Apresentamos um conjunto de hipóteses, chamado sistema de curvas totalmente essencial, e mostramos que sob essas hipóteses, o levantamento natural de f para o recobrimento universal de S (o disco de Poincaré), tem uma dinâmica rica e complicada. Mostramos também que o conjunto de rotação homológico de f é um subconjunto compacto convexo de dimensão máxima e todos os pontos no seu interior são realizados por conjuntos compactos f-invariantes, órbitas periódicas no caso racional.

In this thesis we describe two separate experiments involving the use of gold nanoparticles. The first experiment looks at the use of gold nanoparticles as a localized heat source and the potential application as a cancer treatment. The second experiment, which is the real focus of this thesis, applies gold nanoparticles in the study of the free surface dynamics of glassy thin films. Gold nanoparticles have the ability to strongly absorb the energy in an incident laser beam and convert that energy into heat. Photothermal therapy is a proposed cancer treatment which exploits this ability to irreparably damage cancerous tissues surrounding gold nanoparticles. In the first chapter of this thesis we explain an experiment designed to probe the local temperatures achieved in such a process. Gold nanoparticles are used to stabilize the boundary of an inverse micelle system which contains an aqueous fluorescent dye solution on it's interior. A temperature dependent fluorescence intensity allows us to probe the temperature changes induced by laser irradiation. In the remainder of this thesis we describe a separate experiment involving the use of gold nanoparticles to study the free surface dynamics of thin glassy films. There is a growing body of evidence in the literature that thin polymer films in the glassy state exhibit heterogeneous dynamics; specifically that the first few nanometers from an air-polymer interface exhibit enhanced mobility relative to the interior of the film. The underlying mechanism responsible for this enhanced mobility remains elusive, however some believe it to be a direct consequence of the polymeric nature of these films. We describe in detail an experiment aimed at addressing this concern. We deposit gold nanoparticles onto the surface of a molecular (non-polymeric) glassy film and monitor their behaviour upon heating using atomic force microscopy. Our results clearly show the existence of enhanced surface mobility in the system studied and provide strong evidence that enhanced surface mobility should be expected in all glass forming systems.

In this thesis we describe two separate experiments involving the use of gold nanoparticles. The first experiment looks at the use of gold nanoparticles as a localized heat source and the potential application as a cancer treatment. The second experiment, which is the real focus of this thesis, applies gold nanoparticles in the study of the free surface dynamics of glassy thin films. Gold nanoparticles have the ability to strongly absorb the energy in an incident laser beam and convert that energy into heat. Photothermal therapy is a proposed cancer treatment which exploits this ability to irreparably damage cancerous tissues surrounding gold nanoparticles. In the first chapter of this thesis we explain an experiment designed to probe the local temperatures achieved in such a process. Gold nanoparticles are used to stabilize the boundary of an inverse micelle system which contains an aqueous fluorescent dye solution on it's interior. A temperature dependent fluorescence intensity allows us to probe the temperature changes induced by laser irradiation. In the remainder of this thesis we describe a separate experiment involving the use of gold nanoparticles to study the free surface dynamics of thin glassy films. There is a growing body of evidence in the literature that thin polymer films in the glassy state exhibit heterogeneous dynamics; specifically that the first few nanometers from an air-polymer interface exhibit enhanced mobility relative to the interior of the film. The underlying mechanism responsible for this enhanced mobility remains elusive, however some believe it to be a direct consequence of the polymeric nature of these films. We describe in detail an experiment aimed at addressing this concern. We deposit gold nanoparticles onto the surface of a molecular (non-polymeric) glassy film and monitor their behaviour upon heating using atomic force microscopy. Our results clearly show the existence of enhanced surface mobility in the system studied and provide strong evidence that enhanced surface mobility should be expected in all glass forming systems.

<p>In discussions of heterogeneous catalysis and other surface-related phenomena, the dynamical properties of the catalytic material are often neglected, even at elevated temperatures. An example is the three-way catalyst (TWC), used for treatment of exhaust gases from combustion engines operating at several hundred degrees Celsius. In the TWC, reduced ceria (CeO_2-x) is one of the key components, where it functions as an oxygen buffer, storing and releasing oxygen to provide optimal conditions for the catalytic conversion of the pollutants. In this process it is evident that dynamics plays a crucial role, not only ionic vibrations, but also oxygen diffusion.</p><p>In this thesis, the structure and dynamics of several ionic crystalline compounds and their surfaces have been studied by means of Molecular dynamics (MD) simulations and Lattice dynamics (LD) calculations. The main focus lies on CeO_2-x, but also CeO₂, MgO and CaF₂ have been investigated.</p><p>The presence of oxygen vacancies in ceria is found to lead to significant distortions of the oxygen framework around the defect (but not of the cerium framework). As a consequence, a new O-O distance emerges, as well as a significantly broadened Ce-O distance distribution.</p><p>The presence of oxygen vacancies in ceria also leads to increased dynamics. The oxygen self-diffusion in reduced ceria was calculated from MD simulations in the temperature range 800-2000 K, and was found to follow an Arrhenius behaviour with a vacancy mechanism along the crystallographic <100> directions only.</p><p>The cation and anion vibrational surface dynamics were investigated for MgO (001) using DFT-LD and for CaF₂ (111) in a combined LEED and MD study. Specific surface modes were found for MgO and increased surface dynamics was found both experimentally and theoretically for CaF₂, which is isostructural with CeO₂.</p><p>Many methodological aspects of modeling dynamics in ionic solids are also covered in this thesis. In many cases, the representation of the model system (slab thickness, simulation box-size and the choice of ensemble) was found to have a significant influence on the results.</p>

Studies show that dynamical properties of ultra-thin polymer films deviate from those of bulk materials. Despite some controversial issues, there is growing evidence indicating that the interfacial properties play a key role for observed dynamical anomalies. However, how and how much the interfacial properties affect the average dynamics of the nanometer scale systems are still elusive. In this work, we developed several novel techniques to investigate near-free-surface dynamics of thin polymer films. We studied surface dynamics of glassy i-PMMA films using a nano surface hole relaxation technique: a strong substrate property dependence and an unexpected molecular weight dependence were observed; we found that a local Tg of ~40K below bulk Tg could be assigned to the surface region. We used nano gold particle embedding to study PS surface dynamics: enhanced surface dynamics and weak temperature dependence were observed for the surface region; a depth profile with the nm resolution was observed; viscous liquid-like and soft solid-like properties were observed in the first 5.5nm and next 3.3 nm regions in PS films; no molecualr weight dependence was found in glassy PS films. We built a low level noise measurement system to study the thermal polarization noise in PVAc films: cooperative rearranging dynamics were evidenced; the noise power spectral density (PSD) is found to fluctuate around a certain average level without discernable peak shift; we observed some relatively big jumps or fluctuations in successive integrated PSD’s, which indicate some energy exchange between different microscopic domains in glassy polymer systems. We developed a novel nano rheology AFM technique to study the near-free-surface dynamics of thin polymer films: enhanced near-free-surface dynamics with weak temperature dependence are observed for PVAc films, which is similar with the PS case.

Studies show that dynamical properties of ultra-thin polymer films deviate from those of bulk materials. Despite some controversial issues, there is growing evidence indicating that the interfacial properties play a key role for observed dynamical anomalies. However, how and how much the interfacial properties affect the average dynamics of the nanometer scale systems are still elusive. In this work, we developed several novel techniques to investigate near-free-surface dynamics of thin polymer films. We studied surface dynamics of glassy i-PMMA films using a nano surface hole relaxation technique: a strong substrate property dependence and an unexpected molecular weight dependence were observed; we found that a local Tg of ~40K below bulk Tg could be assigned to the surface region. We used nano gold particle embedding to study PS surface dynamics: enhanced surface dynamics and weak temperature dependence were observed for the surface region; a depth profile with the nm resolution was observed; viscous liquid-like and soft solid-like properties were observed in the first 5.5nm and next 3.3 nm regions in PS films; no molecualr weight dependence was found in glassy PS films. We built a low level noise measurement system to study the thermal polarization noise in PVAc films: cooperative rearranging dynamics were evidenced; the noise power spectral density (PSD) is found to fluctuate around a certain average level without discernable peak shift; we observed some relatively big jumps or fluctuations in successive integrated PSD’s, which indicate some energy exchange between different microscopic domains in glassy polymer systems. We developed a novel nano rheology AFM technique to study the near-free-surface dynamics of thin polymer films: enhanced near-free-surface dynamics with weak temperature dependence are observed for PVAc films, which is similar with the PS case.

Magistrantūros studijų baigiamasis praktinis-kūrybinis projektas, kuriamas naujoje aplinkoje ar pritaikomas jau susiklosčiusioje paveldo situacijoje, susijęs su integravimo aplinkoje ir kontekstualumo problemomis. Architektūrinis ansamblis, derantis su instaliuotu meno kūriniu ne tik vizualiai, bet ir konceptualiai, papildomas lygiagrečiai veikiančia patirtimi, yra suvokiamas kompleksiškai. Svencelės jėgos aitvarų ir burlenčių centro architektūrinis ansamblis pasižymi savitu požiūriu į gamtinę situaciją. Svencelės jėgos aitvarų ir burlenčių centras – rytinėje Kuršių marių pakrantėje įsikūrusi poilsiavietė, įrengta jūriniuose konteineriuose. Teritorijoje įrengta 33 konteinerių, iš kurių 23 yra gyvenami, sutvarkyta aplinka, praplatintas tvenkinys, kuriame sukurta vandenlenčių sporto infrastruktūra. Savita derme su gamta pasižymi darnus architektūros instaliavimas. Šiuolaikiniu požiūriu paremta patirtis leidžia suvokti šį kompleksą kaip lygiagrečiai su gamta egzistuojantį ir deramą pagarbą išlaikantį statinį. Objekto realizacijai panaudoti pažangūs, gamtinės aplinkos nepažeidžiantys sprendimai. Adekvatus požiūris į supančią aplinką ir objekto funkciją, ko gero, yra stipriausias šio projekto aspektas. Svarbiausia – suformuota aplinka, nevaržanti patyrimo pojūčių. Visa komplekso kompozicija dėliojama atsižvelgiant į infrastruktūros patogumą. Atsižvelgiant į architektūrinio komplekso paskirtį svarbiausia šiame komplekse išlieka pagarba gamtai, taigi svarbi idėja, jog pastatai gali... [toliau žr. visą tekstą] / Master's degree final practical-creative project, created a new architectural situation is related to the integration of the environment and the contextual issues. Architectural ensemble, negotiating with an installed piece of art, not only visually, but also conceptually, is perceived holistically. Svencelė kite and windsurfing center architectural ensemble has its own approach to the natural situation. Realization of the object is used the advanced solutions without damaging the natural environment. The complex is equipped with 33 containers, 23 of them are residential. There is an environment for active sports, is widened pond, where is a wakeboarding sports facilities. Adequate treatment of the surrounding environment and the object function is the strongest part of this project. In glass object designing process in the natural - architectural context, the most important factor in the way of expression is ethnic - cultural history of curonian region, the complex function and geographic location behavior - constantly blowing wind. Glass object - a weathercock concept dictated by the wind religious importance in the region. According to local tradition weathervane connects the two experiences: the old etnical and the new architectural expressions. The object looks like a sail or new age weathervane. Composed of several layers of glass overlaps and creates optical illusions of changing, wind-blown form creates additional movement. Glass object is composed of three... [to full text]

Formuojant architektūros ir dailės ansamblį, lemiamu faktoriumi tampa vienos meno srities su kita tarpusavio santykis, priklausomai nuo to, ar jis labiau juslinis ar racionalus, hierarchinis ar ne, akcentuojantis skirtumus ar juos niveliuojantis. Šiuolaikinėje XX a. pabaigos – XXI a. pradžios architektūroje stipriai jaučiama moderniausiųjų menų ir ideologijų įtaka. Pastatas tampa tarpdisciplininiu meno objektu. Sujungiamos menininko ir architekto idėjos, darbo eigoje leidžiančios suvokti architektūrą, kaip skirtingų menininkų derybų objektą, įprasminantį skirtingus kūrybinius pajėgumus. Architektūra įgauna konceptualią formą ir išraišką, kur ypač svarbus architektūrinės raiškos elemento vaidmuo tenka pastato eksterjerams (fasadams). Autonomiška pastato fasado (paviršiaus) traktuotė leidžia daug platesnę raiškos priemonių galimybę. Pastato apvalkalas savo funkcija supanašėja su oda ar rūbu, gyvuoja autonomiškai nuo vidaus struktūros, todėl gali būti dinamiškas, kintantis, daugiasluoksnis, bet tuo pat metu ir monumentalus. Teorinį darbą sudaro trys dalys. Pagrindžiama šiuolaikinės architektūros pastato kaip integralaus kūrinio samprata, aptariama pagrindinė postmodernių fasadų vizualaus suaktyvinimo priemonė - stiklo sąveika su šviesa. Aptariami konkretūs plokščių architektūrinių paviršių suaktyvinimo būdai bei situacija Lietuvoje. Pateikiami objektų pavyzdžiai, apžvelgiant architektūrinių paviršių raiškos galimybes, nagrinėjami panaudojimo tikslai ir rezultatai... [toliau žr. visą tekstą] / In the late XXth – XXIst century architecture strongly felt influence of conteporary arts and ideologies. where essential architectural element of role definition of the building's exterior (facade). Architecture becomes a conceptual meaning in form and expression, where an important part of the architectural expression takes architectural surfaces (facades). Building envelope (surface) in his function converge with the skin or clothing, exists independently of the internal structure, so it can be dynamic, evolving, multi-layered, but at the same time monumental. The theoretical work consists of three particural parts. Describes modern building as an integral part of architectural ensemble, discusses the main postmodern facades visual activation tool - glass interaction with light. Specifies the architectural surface activation techniques and the situation in Lithuania. Describes the architectural objects, overview of the expression capabilitys of the architectural surface. Analyzed the application of architectural glass objects in the environment trends, discusses the future prospects. The third part is devoted to analysis of the particular architectural ensemble and the glass object proposal.