No description available.

Matter exists in many different phases, for example in solid state or in liquid phase. There are also phases in which the ordering of atoms is the same, but which differ in some other respect, for example ferromagnetic and paramagnetic states. According to Landau's symmetry breaking theory every phase transition is connected to a symmetry breaking process. A solid material has discrete translational symmetry, while liquid phase has continuous translational symmetry. But it has turned out that there also exist phase transitions that can occur without a symmetry breaking. This phenomenon is called topological order. In this thesis we consider one example of a theoretical model constructed on a two dimensional lattice in which one obtains topological order.

Este trabalho aborda um tipo de passarela que está ganhando bastante notoriedade internacionalmente. Inúmeras obras vêm sendo construídas em diversos países, embora no Brasil ainda seja quase desconhecida. Basicamente, a estrutura é composta por cabos livremente suspensos, sobre os quais se apóia o tabuleiro formado por elementos pré-moldados de concreto. A protensão é utilizada como forma de enrijecer o conjunto. Dentre suas principais características, estão a rapidez e a facilidade de execução, a estética bastante agradável e o custo competitivo. Inicialmente, apresenta-se uma conceituação básica e um estado da arte. Em seguida, é estudado o comportamento estrutural da passarela. Alguns tópicos relativos à análise dinâmica e às fundações são brevemente comentados. Finalizando a dissertação, é feita uma aplicação numérica, enfatizando os aspectos que a diferenciam das estruturas convencionais / This work treats a kind of pedestrian bridge that is standing out internationally. Several structures have been built in different countries, although they are almost unknown in Brazil. Basically, the deck is formed by precast concrete elements over free suspended cables. Prestressing is applied behind the abutments to provide rigidity to the structure. Quick and easy to assemble, aesthetically beautiful and the competitive cost are some of their main features. First, the basic concepts and a state of art are presented. Then, the structural behavior is studied. Some questions related to dynamic analysis and foundations are briefly commented. Ending the dissertation, an example is done, with emphasis to the aspects that make the stress-ribbon a non-conventional structure

Magister Chirurgiae Dentium - MChD / Post-operative sore throat is a common minor complication following general anaesthesia via endotracheal intubation. Pharyngeal packing has often been implicated in this minor anaesthetic complication. In maxillo-facial and oral surgery, two types of throat packs are commonly used namely ribbon gauze and tampons. In order to establish the efficacy of these two types of throat packs a prospective, randomised, clinical study was conducted. The objectives of the study were threefold: to investigate the effect of the two different types of throat packs on the incidence of post-operative sore throat, to determine the quality of seal provided by the two different types of throat packs and finally, to formulate a faculty protocol. The study consisted of 70 patients undergoing third molar surgery. All the patients were intubated via endotracheal intubation and had a throat pack placed. Patients were also randomly selected and allocated to two groups. One group had ribbon gauze while the other group had a tampon as a throat pack. The study reflected no statistically significant difference in the incidence of postoperative sore throat between the two groups. It was interesting to note that the symptoms of sore throat resolved quicker with the use of tampons. On the other hand, the ribbon gauze provided a better pharyngeal seal. / South Africa

L'homéostasie glutamatergique dans les fentes synaptiques régule la neurotransmission et préserve de l'excitotoxicité. Cela est particulièrement important dans l'oreille interne où il y a une libération soutenue de neurotransmetteur. Pour la plupart des cellules ciliées cochléaires et vestibulaires, la clairance du glutamate est assurée par les transporteurs du glutamate EAAT1 (GLAST) exprimés par les cellules de soutien. Un tel mécanisme n'est pas possible pour les cellules ciliées vestibulaires de type I car leur terminaison synaptique en calice empêche tout accès à la fente synaptique. Nous avons donc postulé qu'un ou plusieurs transporteurs du glutamate devaient être présents au niveau des cellules ciliées de type I ou du calice ou des deux.Grâce à des enregistrements électrophysiologiques, nous avons démontré qu'un courant anionique induit par le glutamate et bloqué par le DL-TBOA est présent dans les cellules ciliées de type I. Les techniques d'hybridation in situ et d'immunohistochimie ont révélé la présence d'EAAT4 et EAAT5. Ces deux transporteurs du glutamate, qui pourraient êtres à l'origine des courants enregistrés, sont exprimés par les cellules ciliées de type I et de type II. De plus, des expériences de RT-PCR et de microscopie électronique ont confirmé ces résultats et suggéré que ces transporteurs pourraient aussi être exprimés postsynaptiquement par le calice. Ces travaux de thèse montrent qu'EAAT4 et EAAT5, considérés respectivement comme spécifiques des tissus cérébelleux et rétiniens, ont une distribution plus large. Ces résultats posent la question des rôles potentiels de ces transporteurs dans l'homéostasie glutamatergique vestibulaire. / Glutamate homeostasis in synaptic clefts shape neurotransmission and prevent excitotoxicity. This may be particularly important in the inner ear where there is a continually high rate of neurotransmitter release. In the case of most cochlear and vestibular hair cells, clearance involves the diffusion of glutamate to supporting cells, where it is taken up by EAAT1 (GLAST), a glial glutamate transporter. A similar mechanism is unlikely to work in vestibular type I hair cells because the presence of calyx endings separates supporting cells from the synaptic zone. Based on this arrangement, we postulated that a glutamate transporter must be present in the type I hair cell, the calyx ending, or both. Using whole-cell patch-clamp recordings, we demonstrated that a glutamate-activated anion current blocked by DL-TBOA is expressed in type I hair cells. In situ hybridization and immunohistochemistry revealed that EAAT4 and EAAT5, two glutamate transporters that could support the anion current, are expressed in both type I and type II hair cells. Furthermore, RT-PCR and immunogold investigations confirmed those results and added that although preferentially expressed presynaptically, the transporters may also be present in the postsynaptic calyx membrane. Previously thought to be exclusively expressed in the cerebellum and retina respectively, this thesis work shows that EAAT4 and EAAT5 have a wider distribution. The potential role of these transporters in the glutamatergic homeostasis of the calyx synapse is then discussed.

The diploma thesis deals with a project of a pedestrian bridge across the valley. At first, there was a comparison of three options of a bridge, then the option of a prestressed concrete band was selected. The main aim of the diploma thesis is the design of the construction, the creation of a model in the programme Ansys 12.1 and the subsequent assessment in accordance with the current regulations.

No description available.

Pedestrian bridge across the river Dyje, which comprises stress concrete ribbon supported by two archs. The structure is designed so that it applied for self-anchored system.

The present study investigates experimentally the laminar mixing and heat transfer of a range of helical ribbon and anchor impellers for both Newtonian and inelastic non-Newtonian fluids. The work also correlates the experimental data empirically in the form of dimensionless groups. In order to estimate the relative importance and the effect of all the geometrical parameters on the mixing power and heat transfer, data from the published literature sources will be utilized and combined with the results from this study. Thus, reliable empirical correlations will be obtained which are applicable over the widest range of operating conditions. The study also investigates the ablity of the various impellers to level out temerature distributions. The measurement of these temperature gradients and the impeller power requirements gives a measure of the mixing efficiency of the impeller used. / Science Research Council

This essay aims to investigate the visual and symbolic language of banners and standards belonging to two Swedish temperance organizations, the Independent Order of Good Templars, and the Swedish Blue-Ribbon Movement. The examined material is 98 banners and standards from Folkrörelsearkivet för Uppsala län. Mieke Bal and Norman Bryson's semiotic starting point in the article "Semiotics and Art History" (1991), mainly based on Charles Sanders Peirce's semiosis, has been used as the method of analysis. Support has also been taken from Roland Barthes' semiotic concepts of denotation and connotation. Visual culture studies, with support from Nicolas Mirzoeff's Introduction to Visual Culture (1999) has been used as a theoretical and structural starting point of the essay. The analysis has shown a rich use of symbolic signs within the material, and that – and how – the use of said symbolic signs is both similar and different between the organizations. The analysis has further demonstrated the possibility to interpret meaning which were communicated through the banners and the standards visual and symbolic language. In the essay's discussion, these meanings have been divided into different themes which can be said to reflect the ideals, ideas, and activities of the organizations. The visual communication is understood based on the activities and religious history of the organizations, and on the political, social, historical, and cultural context of the collective symbols.