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1
Běťák, Petr. "Modelování a návrh ESD ochran v integrovaných obvodech." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-233447.
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The thesis introduces new semiconductor structures that are used as protections against Electrostatic Discharge occuring in integrated circuits. The fundamental structure for modeling and simulation has been lateral Silicon Controlled Rectifier. This SCR structure has been modificated to enable tuning of the triggering and holding voltages by changing geometrical mask dimensions. On the base of modeling and simulation the new proposed structures have been published. Also several protection structures have been designed to be manufactured and measured on a testchip. The final electrical behavior has been verified by measurement. Finally, the focus has been aided to protection circuit with bipolar transistor. This approach has been also simulated and verified by measurement. Advantages and disadvantages of the proposed protection structures are commented in the thesis.
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Tucker, Tony Ralph, and n/a. "Corporate Governance in the Australian Public Service. An examination of success andfailure, with particular reference to the Department of Immigration and Citizenship." University of Canberra. n/a, 2008. http://erl.canberra.edu.au./public/adt-AUC20081209.091200.
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The introduction of New Public Management reforms to the Australian Public Service in the 1980s and 1990s marked a substantial shift away from the traditional process-based public sector model to a market-driven one. These reforms accelerated with the election of the Howard government in 1996, which moved the public sector to become more like the private sector, but failed to address directly the changes needed in accountability and control of the APS. This study explores the evolution of corporate governance as a means of filling that gap in the APS. The ultimate responsibility for ensuring corporate governance is appropriately applied in departments of state rests jointly with the minister and the secretary, in their roles in administering and managing the organisation, and in particular fostering and modelling appropriate organisation citizenship behaviour.
Corporate governance exists In the APS, as in the private sector, as a dichotomy offormal and informal elements, and the informal elements play a paramount role in achieving results for government that are lawful, fair and reasonable; adherence to formal corporate governance processes alone is insufficient to protect an organisation from failure. The example of DIMA was used to demonstrate that even an organisation with a proud international record in assisting the most vulnerable in the world through its refugee and humanitarian programs can fail if its corporate governance mechanisms are not universally and correctly applied throughout the organisation, resulting in outcomes described as "catastrophic" for the individuals concerned.
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Cowie, Euan Niall. "Development of a prototype for the novel disc DIRC for PANDA." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4334/.
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The PANDA experiment is a planned experiment for the FAIR upgrade to GSI in Darmstadt, Germany. It aims to probe the nature of hadronic matter and the Strong nuclear force to unprecedented levels of accuracy and precision. A general purpose detector, covering 4-Pi solid angle, will reside on the High Energy Storage Ring (HESR) racetrack-type accelerator. The HESR will provide a beam of variable momentum anti-Protons which impinge upon a proton target internal to the PANDA detector. To fulfil the physics programme the detector will utilise two Cherenkov detectors based on the Detection of Internally Reflection Cherenkov radiation (DIRC) principle, one in a barrel configuration and one in an disc configuration. A proposed design for the disc configuration DIRC is the Focussing Lightguide Disc DIRC(FLDD). In addition to the novel geometry the FLDD proposes to use a unique hardware element to correct for the chromatic dispersion present in DIRC detectors. Lithium Fluoride was selected to correct for this dispersion and was found to reduce the angular spread resulting by a factor of ~4.7, in agreement with the predicted reduction. A full optical simulation of a prototype accurately reproduced all of the features observed at test beam. Therefore to perform the Pion/Kaon separation required for the PANDA physics programme the design needs a detector surface split into 64 channels or a resolution of 0.78125mm per pixel. Further study of the focussing lightguide element is required to access the full performance of the FLDD design.
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Schmidt, Mustafa Andre [Verfasser]. "Particle identification with the Endcap Disc DIRC for PANDA / Mustafa Andre Schmidt." Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1153334860/34.
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Rieke, Julian [Verfasser]. "Design of a compact photon detection system for the PANDA Disc DIRC prototype / Julian Rieke." Gießen : Universitätsbibliothek, 2017. http://d-nb.info/1136570055/34.
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Etzelmüller, Erik [Verfasser]. "Developments towards the technical design and prototype evaluation of the PANDA Endcap Disc DIRC / Erik Etzelmüller." Gießen : Universitätsbibliothek, 2017. http://d-nb.info/1132994977/34.
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Souza, Maria Conceição Moreira de Almeida. ""Dias & Dias", de Ana Miranda: Gonçalves Dias e outros duplos." Pontifícia Universidade Católica de São Paulo, 2011. https://tede2.pucsp.br/handle/handle/14666.
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Previous issue date: 2011-05-16This thesis presents a study of the novel Dias & Dias , by writer Ana Miranda. In the study, it is intended to highlight the poetic force of the novel and some of its countless possible interpretations. From the literature search that covered several theories of the literary field, the study was developed into three chapters. In the first, the discussions were focused on the creative strategy by Ana Miranda. In the second, the historical game / fictional was discussed. In the last chapter, we seek to unravel the multiple ramifications of the characters based on the theory of the double backed by reflections of scholars of the literature and psychology fields
Esta dissertação apresenta um estudo do romance Dias & Dias, da escritora Ana Miranda. No estudo, intentamos evidenciar a força poética do romance e algumas de suas inúmeras faces possíveis de interpretação. A partir de pesquisa bibliográfica que abrangeu diversas teorias do campo literário, desenvolvemos o estudo em três capítulos. No primeiro, as reflexões foram voltadas para a estratégia criativa de Ana Miranda. No segundo, discutiu-se sobre o jogo histórico/ficional. No último capítulo, buscamos desvendar os múltiplos desdobramentos das personagens, com base na teoria do duplo respaldados por reflexões de teóricos da literatura e psicologia
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Oliveira, Renata Carvalho de. "DIAN - BUFÊ." Florianópolis, SC, 2008. http://repositorio.ufsc.br/xmlui/handle/123456789/91724.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Nutrição.Made available in DSpace on 2012-10-24T01:52:57Z (GMT). No. of bitstreams: 0
Poucos são os estudos que discutem a necessidade de aplicação da rotulagem nutricional em restaurantes, bem como a forma para oferecer essas informações aos consumidores. Assim, o objetivo deste estudo foi desenvolver um método para disponibilizar informações alimentares e nutricionais de preparações oferecidas em restaurantes do tipo bufê. A escolha por este tipo de distribuição deveu-se à sua ampla utilização no mercado de alimentação fora de casa. O estudo foi dividido nas etapas: caracterização teórica dos pontos relevantes sobre informações alimentares e nutricionais; concepção do modelo de método para disponibilizar as informações em preparações de bufês; seleção do local para a realização do estudo de caso; teste de aplicação do método proposto por meio de estudo de caso; elaboração do modelo de etiqueta de informações alimentares e nutricionais; revisão e estruturação do método de Disponibilização de Informações Alimentares e Nutricionais em Bufês (DIAN-bufê). O método estruturado foi organizado em etapas, formulários e recomendações de aplicação. Concluiu-se que as informações alimentares e nutricionais devem ter linguagem simples e de fácil entendimento, sendo apresentadas como etiquetas no balcão do bufê. Quando for utilizado nome fantasia para a preparação, sugere-se uma nomenclatura auto-explicativa, contendo os alimentos da receita em ordem decrescente de quantidade. Optou-se por indicar também informações sobre nutrientes e/ou substâncias relevantes para a saúde dos consumidores, por meio de destaques de alertas (presença de glúten, gordura trans, lactose e/ou açúcar) e destaques de alimentação saudável (presença de cereais integrais, leguminosas, frutas, legumes e/ou verduras), apresentados em forma de ícones nas etiquetas. A principal dificuldade para a aplicação do método DIAN-bufê relaciona-se à pouca existência e à utilização das fichas técnicas de preparação no processo produtivo. Assim, destaca-se necessidade de controle nas modificações de ingredientes e preparações durante o fluxo produtivo, além da conscientização dos operadores quanto à importância da padronização das receitas e das informações alimentares e nutricionais para os consumidores. Considera-se que o DIAN-bufê pode auxiliar na garantia do direito à informação e colaborar para escolhas alimentares mais seguras e saudáveis, constituindo um instrumento de educação nutricional e alimentar, tanto no plano de políticas de saúde quanto no plano individual.
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Topinka, Jiří. "Golden disc." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2014. http://www.nusl.cz/ntk/nusl-232430.
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Chan, Kit-ying, and 陳潔瑩. "Development of whole disc organ culture system and acellular disc scaffold for intervertebral disc engineering." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45600077.
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Hall, S. M. "The energetics of star-disc encounters and disc density profiles." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599855.
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This thesis investigates the response of a circumstellar accretion disc to the fly-by of a perturbing mass on a parabolic orbit, both with and without the presence of dissipation. Observed protostellar number densities and velocity dispersions imply that collisions between protostellar systems are likely during the pre-main sequence phase of their evolution. Observations of the Orion Nebula have revealed 'truncated' discs and with this in mind the post-encounter material distributions are examined and are found to be promising candidates for the observed systems. Finally, the isolated evolution of the disc remnants are studied with a view to studying the motions of 'precessing' or 'wandering' jets.
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Licariao, Berttoni Claudio. "Dias e dias: a escrita em Palimpsesto de Ana Miranda." Universidade Federal de Minas Gerais, 2013. http://hdl.handle.net/1843/ECAP-94LL63.
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Esta dissertação tem como objetivo principal estudar as relações hipertextuais entre o romance 'Dias e dias', de Ana Miranda, e suas fontes declaradas: a obra de Gonçalves Dias e a fortuna crítica e biográfica do poeta. Procura-se não somente identificar o uso dessas fontes, mas compreender os sentidos de sua transformação ou repetição na narrativa. Situando o romance na tradição de retomadas paródicas da 'Canção do exílio', este estudo propõe uma análise que, distanciando-se da classificação já usual do romance como 'ficção histórica', destaca o trabalho com a linguagem, de maneira a sugerir uma nova abordagem crítica para a obra da autora. Com a análise de 'Dias e dias', pretende-se elucidar o experimentalismo da escrita de Ana Miranda a partir da relação que seus romances estabelecem com escritores da tradição literária brasileira.
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Oliveira, Gilvando Alves de. "A constru??o do discurso par?dico na pornochanchada: uma cosmovis?o carnavalesca." PROGRAMA DE P?S-GRADUA??O EM ESTUDOS DA LINGUAGEM, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/21536.
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Nos anos 1970, no Brasil, houve uma efervesc?ncia na produ??o cinematogr?fica e, nesse per?odo, realizaram-se com?dias er?ticas, que foram rotuladas de pornochanchadas. Esses filmes fizeram um grande sucesso frente ao p?blico brasileiro, mas sempre eram ridicularizados pela cr?tica que os julgava como cinema mal realizado. Nesse contexto, parte dessa produ??o cinematogr?fica pode ser classificada como par?dia. Considerando isso, este trabalho, cujo tema ? linguagem e cinema, tem como objeto de investiga??o a constru??o do discurso par?dico e a cosmovis?o carnavalesca na pornochanchada e se insere na ?rea da Lingu?stica Aplicada de perspectiva s?cio-hist?rica. Para realizamos a an?lise, detemo-nos na investiga??o dos elementos verbo-visuais presentes na forma composicional de tr?s com?dias er?ticas produzidas na d?cada de 70 como tamb?m analisamos o projeto de dizer constituidor/constituinte da forma arquitet?nica. Como fundamento te?rico-metodol?gico priorit?rio, baseamo-nos nas formula??es sobre linguagem advindas do C?rculo de Bakhtin (2006, 2010), tais como a concep??o dial?gica de linguagem e as reflex?es atinentes ? analise dial?gica do discurso. A principal refer?ncia ? a obra de Bakhtin (2010b, 2010d) sobre a cosmovis?o carnavalesca, a par?dia, a estiliza??o e o riso carnavalesco.
In Brazil, in the 197 there was an effervescence in film production. In this period, erotic comedies were made and labeled pornochanchadas. These films made a big hit facing to the Brazilian public, but were always ridiculed by critics who judged them as evil done cinema. In this context, part of that film production can be classified as parody. So, this work whose subject is language and film has the object of investigation the construction of parodic discourse and carnival worldview in pornochanchada and is inserted in the area of Applied Linguistics in a socio-historical perspective. In order to carry out the analysis, we are reflecting on the investigation of verbal-visual elements present in the compositional form of three erotic comedies produced in the 1970s, as well as analyze the project of constitutor/constituent saying from architectural form. We take as a priority theoretical and methodological foundation of the formulations about language arising from Bakhtin Circle (2006, 2010), such as the dialogical approach of language and reflections relating to the dialogical discourse analysis. The main reference is the work by Bakhtin (2010b, 2010d) on the carnival worldview, the parody, the styling and the carnival laughter.
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Potts, Jonathan Roger. "Disc-wing aerodynamics." Thesis, University of Manchester, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569224.
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Disc-wings are a class of un-powered, axi-symmetric flight vehicles that use spin to achieve acceptably stable flight characteristics. Examples of commonly encountered disc-wings include the Frisbee sports disc, the athletics discus and the clay pigeon. Historically, it appears that most disc-wing designs have been based on trial and error approaches. The main aim of the present work is to develop a theory of flight for spinstabilised disc-wings that can be used to inform the process of their design. This theory of flight is based both on theoretical analysis and experimental data. It is shown from a simple trim and stability analysis that a disc-wing with positive camber will trim at a positive angle of attack. However, for most axi-symmetric crosssectional shapes, the aerodynamic centre is ahead of the centre of the disc (which by definition is the disc centre of gravity). Hence, the static margin is negative and the disc is unstable in pitch. In practice, a disc-wing must be spun in order to fly successfully. The imparted angular momentum due to the spin means that, through precessional effects, the destabilising pitching moments tend to result in a rolling motion rather than a pitching motion. Thus, without spin, a disc-wing would tumble soon after release. With spin however, the discwing will not tumble, instead it tends to exhibit a relatively benign roll to the left or right, depending on the spin direction. The aerodynamic characteristics of various disc-wing geometries based around a Frisbee sports disc are investigated through a series of wind tunnel experiments on a spinning and non-spinning disc. It is shown that the basic lift and drag characteristics are consistent with those expected for a finite wing of the same aspect ratio. The pitching moment characteristic is key to understanding the resulting disc dynamics. A comparison of pitching moment curves is given, for a number of different cross-sectional profiles, some tested as part of the present work and some taken from data found in the literature. It is shown that the Frisbee cross-section is unique in that the pitching moment is zero at around 9° angle of attack, approximately coincident with the angle attack for best lift to drag ratio, and that the disc is approximately neutrally stable in this region. It is these characteristics that enable a typical Frisbee to fly successfully. Spin has almost negligible effect on aerodynamic forces and moments. Force and moment data is supported by surface pressure data, and by on and off surface flow visualisation. Surface pressure data shows that the aerodynamic centre of the Frisbee cross-section is shifted aft by the presence of an aft pressure peak that is not present on other cross-section shapes. The aft pressure peak is a function of both the upper surface geometry and the presence of the cavity on the under surface of the disc. Flow visualisation and pressure data are used to propose a model of disc-wing flow topology that is dependant on the angle of attack and includes leading edge separation and reattachment, recirculating cavity flow and a pair of trailing vortices. To understand further disc-wing flight dynamics and the effect of aerodynamic characteristics, a six-degree of freedom disc-wing simulation model was developed using Matlab. The simulation is validated against published Frisbee trajectory data obtained from free-flight experiments. Flight profiles are also discussed for a number of different launch conditions consistent with a range of typical Frisbee throws. The simulation is also used to demonstrate that with control moments from suitable control effectors, it is possible to generate a number of proscribed manoeuvres, including a spiral turn and a spiral roll.
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Sturges, Thomas Michael Jebb. "Dirac plasmon polaritons." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/29280.
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We study theoretically graphene-like plasmonic metamaterials, in particular a honeycomb structured array of identical metallic nanoparticles, and examine the collective plasmonic modes that arise due to the near-field dipolar coupling between the localised surface plasmons of each individual nanoparticle. An analysis of the band structure of these eigenmodes reveals a phenomenal tunability granted by the polarisation of the dipole moments associated with the localised surface plasmons. As a function of the dipole orientation we uncover a rich phase diagram of gapped and gapless phases, where remarkably every gapless phase is characterised by the existence of collective plasmons that behave as massless chiral Dirac particles, in analogy to electrons in graphene. We consider lattices beyond the perfect honeycomb structure in two ways. Firstly, we break the inversion symmetry which leads to collective plasmons described as massive chiral modes with an energy dependent Berry phase. Secondly, we break the three-fold rotational symmetry and investigate generic bipartite lattices. In this scenario we progressively shift one sublattice away from the original honeycomb arrangement and observe a sequence of topological phase transitions in the phase diagram, as well as the merging and annihilation of Dirac points in the dispersions. After examining the purely plasmonic response we wish to address the true eigenmodes responsible for transporting electromagnetic radiation. For this reason we examine plasmon polaritons that arise from the strong light-matter coupling between the collective plasmons in a honeycomb array of metallic nanoparticles and the fundamental photonic mode of an enclosing cavity. Here we identify that the Dirac point remains robust and fixed in momentum space, irrespective of the light-matter coupling strength. Moreover, we demonstrate a qualitative modification of the polariton properties through modulation of the photonic environment, including order-of-magnitude renormalisation of the group velocity and the intriguing ability to invert the chirality of Dirac polaritons.
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Lee, Jean-Philip, and Johan Andersson. "Diab Control System." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-37011.
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In order to control a system or process a PID-regulator is often used although they can be difficult to tune so that they give the system a preferred behaviour. The goal with this project is to tune a PID-controller that controls the temperature of a large water tank. The initial systems temperature fluctuates around the set temperature by +/- 1◦C and our goal is to reduce it to +/- 0.5◦C. The project will use the parametric method of a step response in order to evaluate the systems behaviour into a transfer function model that can be PID-tuned. The system was modeled into a a first order model that matches the heating and cooling separately although not together since they have different time constants. Therefore a second order model was made. This model did not match the collected data very good but is used to get a better understanding of the system and figure out what kind of parameters that are required in order to create a better matching model. The final conclusion is that in order to get a matching transfer function of the plant a second order model or higher must be uses and also that more data distributed along more parameters need to be logged in order to understand the entire system behaviour.
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Serafini, Breno Camargo. "Millôres dias virão?" reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/56029.
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Esta tese explora o universo das crônicas de Millôr Fernandes publicadas na revista Istoé e Istoé/Senhor, de 1983 a 1993, analisando a sua relação com o contexto da realidade sociopolítica brasileira e tendo como pano de fundo o processo de redemocratização no País. A partir disso, é feita uma leitura desse momento político através de um enfoque eminentemente sociológico dos textos, em que, a partir da visão do autor, é mostrado o cerne da nossa formação cultural e, consequentemente, um perfil do homem brasileiro. É na análise das diversas páginas, tanto isoladamente como em conjunto, que podemos mostrar como o autor constrói esse processo, inclusive num patamar mais ampliado, inseridas num contexto mundial — do humano brasileiro ao humano universal. Para isso, investiga-se, sob o prisma temático, os artifícios ficcionais dos quais se vale o autor no sentido de oferecer uma visão multifacetada da realidade do País, sob a ótica do humor e da ironia, sem esquecer o fenômeno da globalização da cultura mundial. Através de recursos como a paródia e a ilustração, Millôr oferece um repertório de textos em que se pode vislumbrar um painel onde aparecem nítidas relações entre humor e ideologia. Nesse sentido, a análise proposta dá-se a partir da perspectiva jamesoniana, em vista o contexto social histórico e econômico, passando pelo dialogismo de Mikhail Bakhtin (1981) ― paródia, ironia e carnavalização. A hipótese principal é a possibilidade de leitura da realidade do período histórico através da ficção. Isso se dá a partir de uma reflexão que tem como base um mosaico temático, escorado no humor, que envolve as discussões sobre a época dos fatos, sobre as relações entre humor, arte e papel do intelectual; sobre poder; e sobre a realidade brasileira e universal.This thesis explores the universe of Millôr Fernandes chronicles that were published in Istoé magazine from 1983 to 1993 and analyzes their relationship with the Brazilian sociopolitical reality in the background of the redemocratization process in the country. From this, there is an interpretation of the political moment by an eminently sociological focus of the texts, in which, from the author's point of view, the very core of our cultural heritage is shown and consequently, a profile of the Brazilians. It’s by analyzing the pages, one by one or several together as a collection, that we may demonstrate how the author builds up this process, even in a wider level that is part of a world context — from Brazilian human to universal human. For that, it investigates the fiction stratagems that the author uses to offer a multifaceted view of the reality in the country under the focus of humor and irony without overlooking the phenomenon of the globalization of the world culture. Throughout resources as parody and illustration Millôr offers a repertoire of texts where the reader can have a glimpse of a panel that shows a vivid relationship between humor and ideology. The proposed analysis is made according to Jameson perspective that discuss the text in its social, historical, and economical context and through the dialogism of Mikhail Bakhtin 1981) — parody, irony and Carnival allegory. The main hypothesis is the possibility of understanding the historical period through fiction. The reflection starts at a theme mosaic that is supported by humor; it involves the discussion of the time of the facts, the relationship between humor and art and the role of the intellectual; it is a consideration about power and about the Brazilian reality and the universal reality.
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Teodoro, Inês Maria Velez. "Roça Fernão Dias." Master's thesis, Universidade de Lisboa, Faculdade de Arquitetura, 2019. http://hdl.handle.net/10400.5/19084.
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Smith, Andrew. "Non-linear dynamo action and disc-halo interaction in disc galaxies." Thesis, University of Newcastle upon Tyne, 2012. http://hdl.handle.net/10443/1525.
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We present an observationally constrained model of mass outflow for galactic discs, derived from star formation rate. This is used to supplement a model of the non-linear, mean-field, α2Ω galactic dynamo in the presence of shear. Outflows affect the magnetic pitch angles unexpectedly. This resolves a long standing problem in non-linear dynamo theory, marking a fundamental improvement in the degree of agreement with observations. The mean-field equations are reduced using a modified version of the no-z approximation, to allow for observed flaring of gaseous galactic discs, leaving us with a flared thin-disc model. We have explored two non-linearities to describe the α-effect. We use recent spatially dependent observations of various galaxy properties to evolve the dynamo equations in time. We present results of the steady state magnetic field for both nonlinearities and demonstrate that observables such as local magnetic field strength and magnetic pitch angle can be closely reproduced, using optimum, physically acceptable values of outflow velocity. We apply the model to a number of well observed galactic systems with similar kinematic properties and discuss several sensitivities of the model whilst modifying data sets within the ranges of observational uncertainty.
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Prieske, Silvia. "DISC-dependent versus DISC-independent aspects of non-apoptotic TRAIL signalling." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/39407.
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The Tumour Necrosis Factor (TNF) superfamily member TNF-related apoptosis- inducing ligand (TRAIL) can selectively induce apoptosis in a wide variety of tumour cells in vivo without causing toxicity to normal cells. Consequently, these findings have triggered the design of novel TRAIL-based cancer therapies. Yet, in recent years it has become apparent that human primary tumour cells are often resistant to TRAIL- mediated apoptosis. However, treatment with chemotherapeutics or other biological agents can sensitise these cells to TRAIL-induced cell death whilst leaving normal cells largely unaffected. Importantly, our laboratory has previously shown that TRAIL can act as a specific suppressor of metastasis in types of cancer in which detachment induces sensitisation of TRAIL-resistant tumour cells to TRAIL-induced apoptosis. Conversely however, our laboratory has also contributed to the discovery that human and murine colorectal cancer cell lines in which the Kirsten rat sarcoma viral oncogene homolog ue (KRas) is endogenously mutated were not only resistant to TRAIL - and CD95L -mediated apoptosis induction but tha t stimulation by these ligands also increased motility and membrane ruffling in these cells. Although TRAIL and CD95L have so far only been described to form one type of membrane -associated signalling complex, the so called death -inducing signalling comple x (DISC), which results in the activation of the initiator caspases 8 and 10, the increase in motility was not dependent on caspases or the formation of the DISC. Based on these findings, the aim of this thesis was to delineate the differences between DISC -dependent and DISC - independent non -apoptotic signals triggered by TRAIL receptors (TRAIL -Rs), and to specifically investigate the DISC -independent migration -inducing pathway downstream of TRAIL -Rs in cancer cells bearing endogenously mutated KRas. In this thesis, TRAIL -induced activation of NF-κB and S rc kinase phosphorylation is found to be DISC -dependent. Furthermore, it is demonstrated that TRAIL triggering of the DISC leads to a caspase -dependent, but Src -independent, loss of E -cadherin in epithelial cancer cell lines. Investigating the DISC -independent induction of migration it is demonstrated that KRas -mutated cancer cell lines derived from different tissues do not rely on exogenous stimulus for induction of migration but, instead, employ endogenous TRAIL for autocrine TRAIL/TRAIL -R2 signalling. Intriguingly, this ligand -receptor interaction is required for the entire gain of migratory capacity afforded to cancer cells by oncogenic mutation of endogenous KRas. Migration induced by autocrine TRAIL/TRAIL -R2 signalling does not require caspases and DISC formation, but instead depends on activation of the family of Rho -GTPases. Importantly, inhibition of the kinases ROCKI/II increases the migratory capacity of cancer cells that express wild- type KRas, and this increase in motility is entirely dependent on TRAIL-R2. This identifies naturally occurring ROCK suppression in KRas-mutated cells as the molecular switch that enables endogenous TRAIL and TRAIL-R2 to induce migration rather than apoptosis.
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Borges, Diuvanio de Albuquerque. "Bons dias! de Machado de Assis e a grande dor das coisas que passaram : um sentido solene e alto às palavras de todo dia." reponame:Repositório Institucional da UnB, 2011. http://repositorio.unb.br/handle/10482/10722.
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Dissertação (mestrado)—Universidade de Brasília, Programa de Pós-Graduação em Literatura, 2011.Submitted by Jaqueline Ferreira de Souza (jaquefs.braz@gmail.com) on 2012-06-15T15:07:45Z No. of bitstreams: 1 2011_DiuvaniodeAlbuquerqueBorges.pdf: 447668 bytes, checksum: 05ceb4af0ec195a14a00981f09711436 (MD5)
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O presente trabalho tem como objetivo o estudo das crônicas de Machado de Assis, publicadas na Gazeta de Notícias, entre abril de 1888 e agosto de 1889, na coluna Bons Dias!, reunidas em 2008 por John Gledson. Partindo da relação entre forma literária e processo social, a pesquisa apontará, em três partes, como o gênero se transfigurou ao longo do tempo; quais foram as contribuições de Machado de Assis para a solidificação da crônica como criação literária; como essas formulações estéticas foram fundamentais na formação do escritor e são fundamentais no processo de depreensão da realidade brasileira oitocentista. O ponto de partida será o estudo sobre a gênese desse gênero: como se transmutou ao longo do tempo até atingir suas singularidades literárias. Tratase de uma leitura que implica não só o estudo da crônica em si, como também sua relação com o romance, o conto e a poesia. Um estudo que parte da crônica histórica e seu valor documental à dimensão ficcional, buscando desde o caminhar dos fatos cotidianos até os mais altos graus de formulação estética. Posteriormente, a obra receberá um duplo enfoque: a crônica como campo de experimentações e inovações técnicas e como mecanismo de internalização e depreensão do social. Para que esse estudo seja feito, compreendemos que a inovação estética proporcionada por Machado só foi possível graças às contradições que envolviam a realidade brasileira e que a depreensão desta realidade só foi possível a partir dessas novas formulações. E, por fim, são analisadas de forma mais pontual algumas crônicas que ao longo dos anos foram mais problematizadas por alguns críticos, seja por sua temática em si, o que para nós será uma forma de recorte – a escravidão e a questão da abolição –, quanto pela sua construção em relação a outros gêneros. _____________________________________________________________________________ ABSTRACT
This paper aims to study Bons Dias! by Machado de Assis, which consists of chronicles published between April of 1888 and August of 1889 in the News Gazette and joined in 2008 by John Gledson. Based on the relationship between literary form and social process, the research shows, in three parts, how the genre was transformed over time; what the contributions of Machado de Assis to the solidification of the chronicle as a literary creation were; how fundamental these aesthetic formulations were to the formation of the writer and to the process of apprehension of the nineteenth-century Brazilian reality. In the first chapter, the starting point is the study of the genesis of this genre: how it transmuted over time to reach their literary peculiarities. It is a reading that implies not only the study of chronicles themselves, but also their relationship with novels, tales and poetry. A study that goes from the historical chronicle and its documentary value to the fictional dimension, investigating from the exploration of everyday facts to the highest levels of aesthetic expression. In the second chapter, the novel will receive a double focus: the chronicle as a field of trials and technical innovations and as a mechanism for the internalization and apprehension of society. For this study be done, we understand that the aesthetic innovation provided by Machado was only possible thanks to the contradictions involving the Brazilian reality and that the perception of this reality was only possible due to these new formulations. Finally, some chronicles that were more questioned by critics over the years are examined in a more accurate way. They were speculated by critics due either to their theme itself, which for us is a form of analysis - the issue of slavery and abolition - or its construction in relation to other genres.
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Berg, Svante. "On Total Disc Replacement." Doctoral thesis, Linköpings universitet, Ortopedi och idrottsmedicin, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54290.
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Low back pain consumes a large part of the community’s resources dedicated to health care and sick leave. Back disorders also negatively affect the individual leading to pain suffering, decreased quality-of-life and disability. Chronic low back pain (CLBP) due to degenerative disc disease (DDD) is today often treated with fusion when conservative treatment has failed and symptoms are severe. This treatment is as successful as arthroplasty is for hip arthritis in restoring the patient’s quality of life and reducing disability. Even so, there are some problems with this treatment, one of these being recurrent CLBP from an adjacent segment (ASD) after primarily successful surgery. This has led to the development of alternative surgical treatments and devices that maintain or restore mobility, in order to reduce the risk for ASD. Of these new devices, the most frequently used are the disc prostheses used in Total Disc Replacement (TDR). This thesis is based on four studies comparing total disc replacement with posterior fusion. The studies are all based on a material of 152 patients with DDD in one or two segments, aged 20-55 years that were randomly treated with either posterior fusion or TDR. The first study concerned clinical outcome and complications. Follow-up was 100% at both one and two years. It revealed that both treatment groups had a clear benefit from treatment and that patients with TDR were better in almost all outcome scores at one-year follow-up. Fusion patients continued to improve during the second year. At two-year follow-up there was a remaining difference in favour of TDR for back pain. 73% in the TDR group and 63% in the fusion group were much better or totally pain-free (n.s.), while twice as many patients in the TDR group were totally pain free (30%) compared to the fusion group (15%). Time of surgery and total time in hospital were shorter in the TDR group. There was no difference in complications and reoperations, except that seventeen of the patients in the fusion group were re-operated for removal of their implants. The second study concerned sex life and sexual function. TDR is performed via an anterior approach, an approach that has been used for a long time for various procedures on the lumbar spine. A frequent complication reported in males when this approach is used is persistent retrograde ejaculation. The TDR group in this material was operated via an extra-peritoneal approach to the retroperitoneal space, and there were no cases of persistent retrograde ejaculation. There was a surprisingly high frequency of men in the fusion group reporting deterioration in ability to have an orgasm postoperatively. Preoperative sex life was severely hampered in the majority of patients in the entire material, but sex life underwent a marked improvement in both treatment groups by the two-year follow-up that correlated with reduction in back pain. The third study was on mobility in the lumbar spinal segments, where X-rays were taken in full extension and flexion prior to surgery and at two-year follow-up. Analysis of the films showed that 78% of the patients in the fusion group reached the surgical goal (non-mobility) and that 89% of the TDR patients maintained mobility. Preoperative disc height was lower than in a normative database in both groups, and remained lower in the fusion group, while it became higher in the TDR group. Mobility in the operated segment increased in the TDR group postoperatively. Mobility at the rest of the lumbar spine increased in both treatment groups. Mobility in adjacent segments was within the norm postoperatively, but slightly larger in the fusion group. In the fourth study the health economics of TDR vs Fusion was analysed. The hospital costs for the procedure were higher for patients in the fusion group compared to the TDR group, and the TDR patients were on sick-leave two months less. In all, these studies showed that the results in the TDR group were as good as in the fusion group. Patients are more likely to be totally pain-free when treated with TDR compared to fusion. Treatment with this new procedure seems justified in selected patients at least in the short-term perspective. Long-term follow-up is underway and results will be published in due course.
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Weltz, Max. "Dial over Data solution." Thesis, KTH, Kommunikationssystem, CoS, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91874.
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The increased use of computer networks has lead to the adoption of Internet-based solutions for reducing telephony costs. This has proved to be a boon to callers who can reach the other party directly via the Internet. Unfortunately numerous business persons still need to call to and from mobile phones which are currently a domain where the customers are generally tightly bound to their operators. To provide a simple solution to this problem for companies, Opticall AB has designed an integrated system called the Dial over Data solution, coupling a mobile interface with a low-rate communication channel, which allows calls to be originated remotely at the best price, exploiting the customer company's existing network. This scheme allows the customer company to easily control telecommunications costs, to monitor their employees' efficiency, and more generally speaking to claim a central role in the communications of their employees. The proposed solution allows distant callers (usually employees of the customer company) to benefit from the company's internal network, which is usually more cost effective and offering connectivity to more networks than a cell phone. The Dial over Data solution enables communication between any phone accessible from the customer company's telephony network (such as SIP clients, landline phones, and mobile phones) at a lower cost.</p> This thesis project analyzes existing technologies and compares them to the pre-existing prototype to ascertain the validity of the method and of the components used. This project also explains the improvements brought to the features offered by the DoD solution: the initial prototype has been developed into a stable and functional product, and has been tested internally. Prompted by a need for scalability and additional features, the replacement of Asterisk for the handling of SIP calls by other SIP servers has also been considered and tested.Den nuvarande ökningen av datanätverk har lett till adoptionen av Internetbaserade lösningar för att förminskar kostnader inom telefoni. Tyvärr behöver åtskilliga affärsmän fortfarande ringa till och ifrån mobiler som återstår som ett område där kunderna är fastkedjade till deras operatörer. För att tillföra en enkel lösning till detta problem för kundföretag har Opticall AB planlagt ett integrerat system som kallas Dial over Data som kopplar ihop ett mobilt gränssnitt, med en billig kommunikationsmedel, som tillåter telefonsamtal påbörjas avlägset på det billigaste priset tack vare företagets nätverk. Det ger möjligheten till kundföretaget att vara centralt för sina personals kommunikationer. Det medger ett enkelt sätt att kontrollera kostnader samt övervaka personalens effektivitet. Den Dial over Data lösningen är en lösning som tillåter avlägsen besökarna med kundföretagets inre nätverk kommer att dra nytta av eftersom det är mer kostnadseffektiv och flexibel än en blott mobiltelefon. Denna möjliggör kommunikation mellan SIP-klienter, fast telefoni och mobiltelefoni för en lägre kostnad till företaget utan att framkalla besvär för sina anställda. Konnektiviteten till företagets inre nätverk samt en låg besvärlighetsnivå är garanterade respektive genom konfigurationsförmågan av produkten och ett praktiskt gränssnitt som är redo för korporativkontaktlistor och visar alla informationen som är relevanta till förbrukarnas erfarenhet.</p> Det här avhandlingsprojektet analyserar existerande teknologier och sätter dem i relation till den sedan tidigare framtagna prototypen för att utröna validiteten hos metoden och beståndsdelar. Projektet förklarar även de förbättringar som gjorts till de egenskaper som erbjuds av DOD-lösningen: prototypen har utvecklats till en stabil och funktionell produkt och har testats internt. Driven av behovet för skalabilitet och ytterligare egenskaper har ersättandet av Asterisk för hantering av SIP samtal av andra SIP servers övervägts och testats.
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Kungsman, Jimmy. "Resonances of Dirac Operators." Doctoral thesis, Uppsala universitet, Matematiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-223841.
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This thesis consists of a summary of four papers dealing with resonances of Dirac operators on Euclidean 3-space. In Paper I we show that the Complex Absorbing Potential (CAP) method is valid in the semiclassical limit for resonances sufficiently close to the real line if the potential is smooth and compactly supported. In Paper II we continue the investigations initiated in Paper I but here we study clouds of resonances close to the real line and show that in some sense the CAP method remains valid also for multiple resonances. In Paper III we study perturbations of Dirac operators with smooth decaying scalar potentials and show that these possess many resonances near certain points related to the maximum and the minimum of the potential. In Paper IV we show a trace formula of Poisson type for Dirac operators having compactly supported potentials which is related to resonances. The techniques mainly stem from complex function theory and scattering theory.
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Thumstädter, Torsten. "Parameteruntersuchungen an Dirac-Modellen." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10633955.
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Blaavand, Jakob Lindblad. "The Dirac-Higgs bundle." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:6e081810-f042-4b3e-9f7c-9eee3c930c35.
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The Dirac-Higgs bundle is a vector bundle with a natural connection on the moduli space of stable Higgs bundles on a compact Riemann surface. It is a vector bundle of null-spaces of a Dirac-operator coupled to stable Higgs bundles. In this thesis, we study various aspects of this bundle and its natural connection. The Dirac-Higgs bundle is hyperholomorphic on the smooth hyperkähler moduli space of stable Higgs bundles. This property is a generalisation of the four-dimensional anti- self-duality equations to hyperkähler manifolds. One use of the Dirac-Higgs bundle is the construction of a Nahm transform for Higgs bundles. This transform produces hyperholo- morphic bundles on the moduli space of rank one Higgs bundles. The Higgs bundle moduli space is non-compact and we study the asymptotics of the connection in the Nahm transform of a Higgs bundle. We show that elements of the null- spaces concentrate at a finite number of points on the Riemann surface. This asymptotical behaviour naturally defines a frame for the Nahm transform, which is conjectured to be asymptotically unitary. By considering only the holomorphic structure, the Nahm transform of a Higgs bundle extends to a holomorphic bundle on the natural compactification of the rank one Higgs bundle moduli space. We discuss various aspects of this extended holomorphic bundle. Most importantly, it is a sheaf extension in which the constituent sheaves and the extension class have natural interpretations in terms of the original Higgs bundle. Furthermore, the extended bundle is not fixed at the divisor at infinity; explicit examples show that it depends on the type of Riemann surface, for example. The Dirac-Higgs bundle has a parabolic cousin. In the parabolic case the rank depends on the number of marked points and the total multiplicity of the zero weights in the parabolic structure. The moduli space of stable rank two parabolic Higgs bundles on the Riemann sphere with four marked points has complex dimension two. Furthermore, there is a combination of parabolic weights such that the Dirac-Higgs bundle is a line bundle with an instanton connection. We study the topology of this line bundle and find that the instanton does not have finite energy. As in the non-parabolic case we define a Nahm transform for parabolic Higgs bundles, and in the case of genus one Riemann surfaces use it to produce doubly-periodic instantons of finite energy.
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Lau, K. S. "Position controlled disc valve." Thesis, University of Surrey, 1987. http://epubs.surrey.ac.uk/847625/.
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Recent developments of electro-hydraulic disc valves at Surrey University have shown that with a careful balance between the hydraulic and magnetic forces, this type of valve can be used as a digital or proportional device. As the valve is simpler in construction and involves very few critical dimension compared with a servo-valve, the sensitivity to contamination is considerably reduced. The dynamic response of the valve is fast due to utilising high electro-magnetic and fluid forces for actuation. The research described in this thesis is an extension of earlier work by Yuksel and Usman to improve electro-hydraulic disc valves by applying closed-loop position or pressure control to the disc. From an investigation of an unbalanced single disc valve, it was found that using position feedback can help to stabilise the disc under varying load conditions. A special differential capacitive transducer to measure the disc position was designed and constructed and was found to perform satisfactorily. As the pressure-flow characteristic of the valve can be varied by controlling the disc position, the function of the valve is similar to an electrically controlled variable orifice. Various modular configurations are proposed to perform more complicated control functions. In the final part of the research, a double disc valve is described for used in an application study to control the damping characteristic of a modified vehicle shock absorber. Initially, the valve was designed for closed-loop position control due to the non-linear hydraulic and magnetic forces. Results show that the valve can be controlled to generate the required range of damping force and has adequate dynamic performance with a response time in the range of 10 to 30 msec. However, tests using direct pressure control were also carried out. Preliminary results indicate that pressure feedback is preferable to position feedback and that by using lead compensation together with a proportional plus integral controller, stable operation is possible.
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Khan, Shahnaz. "The effect of the intervertebral disc microenvironment on disc cell and mesenchymal stem cell behaviour : implications for disc degeneration and regeneration." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-effect-of-the-intervertebral-disc-microenvironment-on-disc-cell-and-mesenchymal-stem-cell-behaviour-implications-for-disc-degeneration-and-regeneration(b5629a75-4cb0-45d8-affb-2b936d9408e1).html.
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Intervertebral disc (IVD) degeneration is associated with low back pain (LBP). It has been suggested that changes in the IVD physio-chemical microenvironment (i.e. hypoxia, reduced nutrient and acidic conditions) may lead to disc degeneration. Studying the response of human nucleus pulposus (NP) cells to these conditions could establish the causal relationship between IVD microenvironment and aberrant cellular behaviour, characteristic of disc degeneration. Human bone marrow mesenchymal stem cells (BM-MSCs) are a promising cell population for disc regeneration. However, knowledge of their survival and functioning in the microenvironment of the IVD is still lacking. Moreover, in vitro co-culture model studies that are used to study MSC/disc cell interaction, also need to consider the effect of the microenvironment on cellular responses. BM-MSCs and degenerate NP cells were cultured alone or co-cultured in monolayer under hypoxia (2%O2), reduced nutritional (2% serum or/and 5mM glucose) and acidic (moderate pH 6.8 or severe pH 6.5) conditions alone or in combination for 7 days. Cell viability, proliferation, gene and protein expression was assessed. Degenerate NP cells and BM-MSCs maintained good cell viability under all conditions. Both cell types demonstrated overall similar proliferation and gene and protein responses under the majority of the conditions and combinations studied. Hypoxia promoted aggrecan and versican matrix biosynthesis in both cell types. Nutrient deprived and moderate acidic conditions (pH 6.8) inhibited proliferation of both cell types. Interestingly the combination of hypoxia with these conditions showed a protective effect in modulating cell proliferation. These results imply that hypoxia may be beneficial in some instances. Nutrient deprived conditions had a relatively minor effect on degenerate NP cell gene and protein expression but these conditions specifically inhibited VCAN expression in BM-MSCs. The combination of hypoxia with these conditions increased or restored VCAN expression. Interestingly the combination of hypoxia with reduced glucose conditions increased aggrecan and versican matrix biosynthesis in both NP cells and BM-MSCs. The combination of hypoxia and complete nutrient deprived conditions (both reduced serum and reduced glucose) impaired ACAN, VCAN and PAX-1 gene and aggrecan and versican protein expression in degenerate NP cells implicating disc hypoxia and complete nutrient deprived combined microenvironment in accelerating degenerate changes in NP cells. In contrast, these conditions showed no such detrimental effects on BM-MSC gene and protein expression. pH 6.5 was critical for both cell types proliferation and ACAN and VCAN gene expression suggesting that severe acidic conditions may exacerbate degenerative changes and be inhibitory for implanted MSCs. Finally, a combination of hypoxia, complete nutrient deprived and moderate acidic conditions, reduced cell proliferation without affecting the gene expression profile of both cell types. IVD-like physio-chemical microenvironmental conditions also appeared to influence differentiation of BM-MSC and modulation of degenerate NP cell phenotype observed during co-culture. Noticeably hypoxia, reduced serum or reduced glucose conditions stimulated BM-MSC differentiation and modulation of degenerate NP cell phenotype. Hypoxia also increased or recovered changes at gene expression level in both BM-MSCs and degenerate NP cells under nutrient deprived (reduced serum or/and reduced glucose) conditions during co-culture. Degenerate NP cell and BM-MSC co-culture also showed noticeable increase in aggrecan and versican biosynthesis under hypoxia and reduced glucose combine conditions, implicating these in improving the co-culture responses. Severe pH condition alone, pH 6.8 in combination with hypoxia and finally all IVD-like physio-chemical conditions together compromised co-culture responses. Such results imply that IVD-like physio-chemical microenvironmental conditions may influence MSC based regenerative outcomes. This work has increased our understanding about the influence of disc harsh microenvironment on degeneration and regeneration processes.
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Wang, Shaobai. "In vivo lumbar spine biomechanics : vertebral kinematics, intervertebral disc deformation, and disc loads." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70430.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references.
Knowledge of lumbar spine biomechanics in living human subjects is fundamental for understanding mechanisms of spinal injury and pathology, for improvement of corresponding clinical treatments, and for design of spinal prosthesis. However, due to the complicated spine anatomy and loading conditions as well as high risks in these direct measurements, it has been a challenge to determine the in vivo biomechanics of the lumbar spine. To address this problem, the overall objective of this thesis was to develop and implement a dual fluoroscopic imaging system to non-invasively study human lumbar spine biomechanics. In line with this objective, the first goal was to quantify the ability of the dual fluoroscopic imaging system to determine vertebral kinematics. The second goal was to implement this technique to investigate spinal motion in both healthy subjects and patients with pathology. The third goal was to explore the feasibility of using kinematic data obtained from this system as boundary conditions in finite element analysis to calculate the physiological loads on the intervertebral disc. The system was shown to be accurate and repeatable in determining the vertebral kinematics in all degrees of freedom. For the first time, six degree-of-freedom motion of different structures of the spine, such as the vertebral body, intervertebral disc, facet joint and spinous process were measured in vivo in both healthy subjects and subjects with pathology during functional activities. In general, the group of subjects with pathology showed a significantly abnormal kinematic response during various physiological functional activities. Preliminary studies have shown the applicability and high accuracy of finite element modeling to calculate disc loads using in vivo vertebral kinematics as displacement boundary conditions.
by Shaobai Wang.
Ph.D.
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Valente, Daniela França Chagas Batista. "A nação cartografada nos romances Desmundo e Dias e Dias, de Ana Miranda." Universidade Federal de Viçosa, 2018. http://www.locus.ufv.br/handle/123456789/22586.
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Ana Miranda é uma escritora reconhecida na cena da literatura brasileira contemporânea, tendo sido agraciada com importantes prêmios da crítica brasileira. Ela tem sido destacada por sua interlocução entre a história e a literatura. O presente trabalho pretende investigar os romances Desmundo (1996) e Dias e Dias (2003), analisando a representação da nação no romance , bem como a representação da personagem feminina nos romances. Seus livros têm como pano de fundo dois momentos fulcrais da história do Brasil: a colonização e os processos de independência. Assim, faz-se necessária uma leitura da história do Brasil, de modo a cotejar a leitura crítica que Miranda faz com a representação dos textos clássicos, como a Carta de Caminha. Por fim, foi feita uma análise de como a escritora apresenta, em sua a obra, a situação da mulher, problematizando e questionando a sociedade patriarcal a partir de temas como o casamento. Para fundamentar este trabalho, foram destacadas várias criticas feministas da literatura, que formularam importantes contribuições sobre a situação da mulher, assim como nomes icônicos da teoria feminista, especialmente, Simone Beauvoir e Virginia Woof.
Ana Miranda is a writer recognized of the Brazilian contemporary literature having been awarded important prizes by Brazilian critics. Shiite has been highlighted by critics for her interlocution between a story and a literature. The present work investigated the novels Desmundo (1996) and Dias e Dias (2003) analyzing the representation of religion in the novel, as well as a presentation of the women's representation in the novels. The novels have a background a vision and a process of independence, as well as a reading of the; history of Brazil, a way of making a critical critique of Miranda makes of the history with Translation, of classic texts, like the Letter of Caminha. Finally, an analysis was made of a writer in her work of a woman, to problematize a patriarchal society, starting with themes such as marriage. The foundation of the work was highlighted by several active women in literature, especially in relation to the situation of women and iconic names in feminist theory, especially Simone Beauvoir and Virginia Woolf.
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Tampier, Claudio. "Progressive Disc Herniation: An investigation of the mechanism using histochemical and microscopic techniques." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2797.
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Abstract Background: The process that involves the migration of the nucleus pulposus from the innermost annular layers and culminates with the final extrusion of the nucleus has been limited to a few studies. This investigation was directed towards a better understanding of the herniation process. The architecture of the annulus fibrosus and the mechanism of progressive disc herniation were analyzed, using a controlled porcine model. Microscopic and histochemical techniques were employed. Methodology: Two studies were performed. In the first stage, the macroscopic and microscopic structures of twelve cervical intervertebral discs were compared with young human disc data from studies reported in the literature. Important structural features were studied such as annulus fibrosus thickness, number of lamellae, lamellae thickness, orientation of the lamellae fibers and blood supply. In the second study, sixteen fresh-frozen functional spine units were submitted to repetitive flexion?extension motions combined with a low compressive load in a servo-hydraulic dynamic testing system. Discograms, dissections and histochemical techniques were applied to characterize the cumulative damage. The experiment produced eight complete herniations, four partial herniations and four specimens without any microscopic detectable annular damage.
Results and Discussion: The structure of the cervical porcine disc resembles the lumbar human disc. Some differences are evident. The size of the annulus is smaller, the thickness of the lamellae is narrower and the number of layers is fewer in the pig. It is hypothesized that the flexion-extension motion combined with a low-level load produced an increased hydraulic pressure in the inner wall of the posterior annulus. This pressure and repetitive motion first produced a small cleft, spreading the collagen bundles inside the first layer. The nuclear material was "pumped" through the small cleft to the first layer filling the layer creating a fluid-filled pocket between the collagen fibers. Once the "pocket" acquired enough pressure a new cleft was produced in the weakest part of the layer allowing the nuclear material to create a new "pocket" in the second layer. This was the first stage of damage and disc herniation production. This mechanism was repeated until the nucleus traveled along the annulus reaching the posterior longitudinal ligament. At this point a complete extrusion herniation was produced.
Conclusion: The porcine model appears to be suitable as a model to understand the mechanism of disc herniation when the spine is subjected to flexion-extension motions combined with a low-level load. The first cumulative injury appears to be a cleft between the lamellae bundles produced by the nuclear hydraulic pressure. A cumulative load/cumulative injury model approach was used to create the damage that was quantified in the study.
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Eufrauzino, Lara de Figueiredo. "Marketing pol?tico e m?dias sociais: as estrat?gias utilizadas no facebook e twitter de C?ssio Cunha Lima PSDB/PB, nas elei??es de 2014." Universidade Federal do Rio Grande do Norte, 2015. http://repositorio.ufrn.br/handle/123456789/21116.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Este trabalho se prop?e a compreender o processo e as pr?ticas das estrat?gias de marketing pol?tico aplicadas ?s m?dias sociais facebook e twitter de um candidato a governador da Para?ba nas elei??es de 2014. Visando atingir o prop?sito desta pesquisa, foi realizado um estudo de caso tendo como objeto de an?lise a campanha online do candidato a governador da Para?ba, C?ssio Cunha Lima - PSDB, em 2014. O estudo de caso se deu a partir da constru??o de um perfil biogr?fico e pol?tico do candidato. Esta pesquisa tamb?m fez uso da etnografia virtual. Para tanto, foram monitoradas as m?dias sociais facebook e twitter desse pol?tico, com o aux?lio do programa de captura de imagens - Greenshot, atrav?s da cria??o de categorias de an?lise pr?-definidas, como, por exemplo, agenda, prest?gio e apoio, campanha negativa, engajamento, entre outras. O per?odo escolhido para o monitoramento dos perfis oficiais de C?ssio Cunha Lima foi entre os dias 24 de agosto e 28 de outubro de 2014, pois comporta o per?odo pr?, durante e p?s-elei??o onde observou-se maior n?vel de movimenta??o do candidato e de sua equipe de marketing nas m?dias sociais selecionadas para an?lise.
This dissertation aims to analyze and understand the process and practices of political marketing strategies applied to social media facebook and twitter C?ssio Cunha Lima - PSDB candidate for governor of Para?ba, in the 2014 elections The work is divided into three parts . The first two chapters, both of theoretical nature, underlie the discussion about the use of the Internet as a campaign space and political marketing campaign as well as the different communication strategies and electoral marketing already presented in the literature. Following, is dedicated to a topic for the presentation of the methodology and subsequently makes the discussion of empirical data analysis. Finally, we present the conclusions. The analysis takes as its starting point the models Figueiredo et al. (1998) and Albuquerque (1999) to observe the traditional strategies and suggests the inclusion of typically recorded on the Internet strategies. The methodology used for the analysis was the qualitative and quantitative content from variables that we list different campaign strategies. In order to achieve the purpose of this research, we conducted a case study as an analytical object online campaign C?ssio Cunha Lima. The case study took place from the construction of a candidate's biographical and political profile, presented and discussed in the text. This research also made use of virtual ethnography. Therefore, were monitored social media facebook and twitter that political, with the help of image capture program - Greenshot by creating pre-defined categories of analysis, for example, calendar, prestige and support, negative campaign , engagement, among others. The period chosen for monitoring the candidate's official profiles was from 24 August to 28 October 2014, because it holds the pre, during and post-election where there was greater candidate drive level and his team marketing in social media selected for analysis. The results indicate that mobilization strategy (online and offline), merged with the promotion schedule, it is predominant in the social media Cassio. They also indicate that they do not show the failure of the campaign of the candidate in 2014.
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Oliveira, André Maciel de. "A literatura de gênero gay em um dia me disseram que as nuvens não eram de algodão : contos homoeróticos de Antonio de Pádua Dias da Silva." Universidade Estadual de Londrina. Centro de Letras e Ciências Humanas. Programa de Pós-Graduação em Letras, 2013. http://www.bibliotecadigital.uel.br/document/?code=vtls000188655.
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Nesta dissertação nos propomos a analisar a homossexualidade na Literatura, através da abordagem das temáticas gays: Homoafetividade, Homoerotismo e Homofobia, através das personagens, narradores ou não, oniscientes ou neutros na obra Um dia me disseram que as nuvens não eram de algodão contos homoeróticos, do escritor e professor paraibano Antonio de Pádua Dias da Silva. Estas terminologias serão analisadas individualmente a partir de seis narrativas, que se encontram cada par de textos, em uma das três partes da obra, assim denominadas: Parte I Nuvens de algodão (Umidade Relativa do Ar: Mínima), Parte II Nuvens Carregadas (Umidade Relativa do Ar: Temporal), Parte III As Nuvens não eram de Algodão (Umidade Relativa do Ar: Tsunami). Em cada uma das partes da obra, através da tipologia de narradores, analisaremos as temáticas gays. Para a apresentação destas análises, dividimos esta dissertação em quatro capítulos, dispondo de: Histórico da Homossexualidade, o autor, sua obra e seu papel desenvolvido junto à crítica; Apresentação e análise dos textos O gorila e Caso da Cueca, abordagem da tipologia de narradores e a homoafetividade; Discussão do homoerotismo nas narrativas O homem que gostava e Tratado acerca da agonia; a homofobia explorada nas narrativas: Beijo escaldado e Velho deitado na grama, bem como as características que identificam cada um dos narradores nos textos. Estas análises ocorreram em virtude da afirmação de existência desta literatura de gênero gay, aqui apresentada por Silva. Com a conclusão das análises identificaremos as características que determinam esta obra como Literatura.In this dissertation, we propose to examine homosexuality in literature, by addressing the gay themes: Homo-affection, homoeroticism and homophobia, through the characters, narrators or not omniscient or neutral in the work Um dia me disseram que as nuvens não eram de algodão - homoerotic tales, of the Paraiba's State writer and teacher Antonio de Pádua Dias da Silva. These terminologies are analyzed individually from six narratives, which are each pair of texts in one of the three parts of the work, so named: Part I Nuvens de algodão (cotton Cloud) (Relative Humidity: Low), Part II Nuvens Carregada (Loaded Cloud) (Relative Humidity: Storm), Part III As nuvens não eram de algodão (The clouds were not made of Cotton) (Relative Humidity: Tsunami). In each part of the work, through the typology of narrators, we look at the gay themes. For the presentation of these analyzes, we divided this thesis into four chapters, featuring: History of Homosexuality, the author, his work and his role developed by the criticism; Presentation and analysis of texts "O Gorila" (The Gorilla) and O Caso da Cueca (Case of the Underpants), approach of typology of narrators and homo-affection; Discussion of homoeroticism in the stories "O Homem que gostava (The man that liked) and "Tratado acerca da agonia (Treaty on the agony); homophobia explored in the narrative: "Beijo Escaldado (Scalded Kiss) and "Velho deitado na grama (Old Man lying on the grass), as well as the characteristics that identify each of the narrators in the texts. These analyzes were conducted under the claim of existence of gay gender literature, here presented by Silva. With the completion of the analysis we will identify the characteristics that make this work as literature.
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Schmidt, Stuart. "Applied rock cutting : a study of partial face disc cutting with blunt disc cutters /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18740.pdf.
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Pacheco, Mário Henrique Gomes. "Propriedades termodinâmicas do oscilador de Dirac e algumas contribuições da função theta de Jacobi." reponame:Repositório Institucional da UFC, 2007. http://www.repositorio.ufc.br/handle/riufc/12418.
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PACHECO, Mário Henrique Gomes. Propriedades termodinâmicas do oscilador de Dirac e algumas contribuições da função theta de Jacobi. 2007. 65 f. Tese (Doutorado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2007.Submitted by Edvander Pires (edvanderpires@gmail.com) on 2015-05-22T20:39:15Z No. of bitstreams: 1 2007_tese_mhgpacheco.pdf: 348432 bytes, checksum: a820f6b5450ff322d4336320ad27ec1d (MD5)
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In this work we analyze the three-dimensional Dirac oscillator in a thermal bath. We found that the heat capacity is two times greather than the heat capacity of the one-dimensional Dirac oscillator in the higher temperatures. We begin with the energy spectrum of the three-dimensional Dirac oscillator, then we find the partition functions and others thermodynamics properties; thus we make one comparasion with the one-dimensional Dirac oscillator and non-relativistic harmonic oscillator. We are interested in study numerically the properties thermodynamics of the square well with infinity potencial. In the latter case we have used a Jacobi theta function.
Nesta tese analisamos o oscilador de Dirac tridimensional em um banho térmico. Encontramos que o calor específico do oscilador de Dirac tridimensional é duas vezes maior que o calor específico do oscilador de Dirac unidimensional quando estamos em um regime de altas temperaturas. Inicialmente utilizamos o espectro de energia do oscilador de Dirac tridimensional para encontramos a função de partição e as demais propriedades. Assim procedendo, fizemos uma comparação com oscilador de Dirac unidimensional e com oscilador harmônico não-relativístico. Em seguida, fizemos um estudo numérico das propriedades termodinâmicas de um poço quadrado de potencial infinito. Para este estudo nós utilizamos a função theta de Jacobi.
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Fran?a, Patricia Gallo de. "A aprendizagem transm?dia na sala de aula: potencialidades de letramento midi?tico." Universidade Federal do Rio Grande do Norte, 2015. http://repositorio.ufrn.br/handle/123456789/20687.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
A tese Aprendizagem Transm?dia na Sala de Aula: Potencialidades de Letramento Midi?tico teve como principal objetivo investigar a aprendizagem transm?dia como uma abordagem pedag?gica de letramento midi?tico junto a professores e alunos das s?ries finais da educa??o b?sica p?blica. Para tanto, desenvolvemos uma pesquisa qualitativa a partir do uso das diretrizes investigativas da etnometodologia (GARFINKEL, 1967; COULON, 1995a), pelo fato de caracterizar-se pelo estudo de atividades cotidianas dos indiv?duos, com aten??o ao modo como eles tomam decis?es, comunicam, resolvem problemas, raciocinam, seja por a??es corriqueiras seja por eruditas, por meio de tecnologias e m?dias; bem como pela pesquisa-a??o (THIOLLENT, 2003), no que se refere ? interven??o pedag?gica proposta por n?s. Assim, a pesquisa ? apresentada em duas etapas, a saber: 1) o uso das tecnologias e m?dias no processo de ensino-aprendizagem, investigando alunos e professores; 2) a aprendizagem transm?dia na sala de aula, uma interven??o pedag?gica na escola-campo de pesquisa. Os dados foram analisados por unidades relacionais, considerando o tema central: uso de tecnologias e m?dias. Como resultado, constatamos que: o livro did?tico ainda ? o principal suporte utilizado pelo professor; as tecnologias e m?dias digitais apenas s?o mencionadas pelos alunos quando estes realizam atividades de cunho acad?mico por iniciativa pr?pria; o letramento midi?tico do professor interfere na abordagem de privilegiar e mediar o letramento midi?tico dos alunos. Assim, conclu?mos que a aprendizagem transm?dia modificou a din?mica de ensino-aprendizagem, propiciando maior entusiasmo e intera??o dos alunos com/sobre o objeto de conhecimento, estabeleceu um di?logo significativo entre professoraluno e aluno-aluno, al?m de ter potencialidade de letramento midi?tico.
The thesis Transmedia Learning in the Classroom: the potential of media literacy aimed to investigate transmedia learning as a pedagogical approach of media literacy with teachers and students of the final grade in public basic education. For this, we developed a qualitative research using the investigative guidelines of ethnomethodology (GARFINKEL, 1967; COULON, 1995a ), by the fact it is characterized in individuals daily activities study, with attention to how they make decisions, communicate, solve problems, reason, whether by ordinary or erudite shares through technologies and media, as well as we use the action research guidelines (THIOLLENT, 2003), in regard to educational intervention proposed by us. Thus, our research is presented in two stages, namely: 1) the use of technology and media in the teaching and learning process, investigating students and teachers; 2) the transmedia learning in the classroom, an educational intervention in school where we developed this research. The data collected were analyzed in relational units considering a central theme: the use of technology and media. As a result we found that textbook is still the main media used by teacher; technologies and digital media are only mentioned by students when they carry out educational activities on their own initiative; teachers? media literacy interfere in their approach to conduct, prioritize and mediate the students media literacy process. Thus, we conclude that transmedia learning changed the dynamics of teaching and learning in classroom, providing greater enthusiasm and interaction of students with / about the object of knowledge, established a meaningful dialogue between teacher-student and studentstudent, as well as transmedia learning has potential of literacy media.
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Pinto, Ana Sofia Lopes. "O impacto das alergias alimentares no dia-a-dia." Master's thesis, [s.n.], 2013. http://hdl.handle.net/10284/4179.
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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências FarmacêuticasA maioria das pessoas pode desfrutar da imensa variedade de alimentos existentes sem qualquer consequência, no entanto, para uma pequena percentagem, determinados alimentos causam reacções adversas que podem ser fatais. Estas reacções ocorrem quando o sistema imunológico, erradamente, reconhece um alimento como agressor do organismo e são designadas por Alergias Alimentares. A sua prevalência tem aumentado expressivamente nos últimos anos, sendo difícil avaliar com rigor a sua taxa de incidência. Esta patologia envolve mecanismos imunológicos que podem ser mediados por IgE, por células ou por ambas. As manifestações clínicas variam entre as leves, como a urticária, até às mais severas como a morte por reacção anafiláctica. Na europa os alimentos causadores de alergia mais comuns são o leite de vaca, ovos, frutos secos e frutas. Uma vez que o principal tratamento da alergia alimentar ainda é a eliminação da dieta do alimento responsável, um diagnóstico rápido e correcto é imprescindível para o direccionar e evitar que a ingestão de nutrientes fique comprometida. O presente trabalho teve como objectivo identificar a incidência de alergias alimentares e analisar o seu impacto na vida diária dos inquiridos. Para tal aplicou-se um inquérito a 134 estudantes da Universidade Fernando Pessoa de forma aleatória. Após a análise verificou-se que na maioria os inquiridos participantes são do sexo feminino (76,9%), sendo a prevalência de alergias alimentares de 12,7% (13 raparigas e 4 rapazes). Os principais alimentos apontados como responsáveis são os frutos secos e os morangos, ambos com 17,6% de predomínio, sendo os sintomas prevalentes as erupções cutâneas e urticária (29,5%). Dos 17 estudantes com alergia alimentar 11 afirmam ter familiares com a mesma patologia, sendo em 27,3% dos casos a mãe ou o pai. Concluímos que a alergia alimentar não constitui uma limitação significativamente negativa para o dia-a-dia dos inquiridos, no entanto, estes afirmam, em contradição, ter receio no aparecimento de novos alimentos causadores de alergia. A alergia alimentar é um tema emergente, porém para o seu melhor conhecimento é imprescindível a realização de mais estudos adequados.
Most people can enjoy a large variety of existing food without consequences, however, for a small percentage, certain foods cause adverse reactions which may be fatal. These reactions occur when the immune system mistakenly recognizes a food as the aggressor in the body and are called Food Allergies. Its prevalence has increased dramatically in the last years, it is difficult to assess accurately their incidence rate. This pathology involving immune mechanisms may be mediated by IgE, the cells or by both. Clinical manifestations range from a less aggressive reaction, such as a skin rash, to the most severe such as death by anaphylactic reaction. In Europe, common foods that cause most allergies are dairy milk, eggs, nuts and fruit. Since the primary treatment of food allergy is still the elimination of the food responsible from the diet, prompt and correct diagnosis are essential to target treatment and prevent nutrient intake compromised. This study aimed to identify the incidence of food allergies and analyze their impact on the daily lives of the respondents. In order to study the case, a survey was applied to 134 random students at the University Fernando Pessoa. After analyzing, it was found that most respondents were female participants (76.9 %), and there for the prevalence of food allergies was also higher with 12.7% (13 female and 4 male). The main foods responsible for these allergies are nuts and strawberries, both with 17.6 % of prevalence and the main symptoms prevalent are skin rashes and hives (29.5 %). 11 out of the 17 student with food allergies claim to have relatives with the same disease and in 27.3 % of cases it is the mother or father. We conclude that food allergy is not a significantly negative limitation for the day-to-day lives of respondents, however, they say, in contradiction, that they are afraid of the possibility of new food allergies appearing. Food allergy is an emerging issue, however for its best knowledge, it is essential to carry out more appropriate studies.
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Ginoux, Nicolas. "Dirac operators on Lagrangian submanifolds." Universität Potsdam, 2004. http://opus.kobv.de/ubp/volltexte/2005/562/.
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We study a natural Dirac operator on a Lagrangian submanifold of a Kähler manifold. We first show that its square coincides with the Hodge - de Rham Laplacian provided the complex structure identifies the Spin structures of the tangent and normal bundles of the submanifold. We then give extrinsic estimates
for the eigenvalues of that operator and discuss some examples.
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Tronati, Michela. "L'equazione di Dirac e l'antimateria." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13509/.
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Il 13 novembre 1995, a undici anni dalla sua morte, nell' Abbazia di Westminster, si è celebrata una manifestazione in memoria di Paul Adrien Maurice Dirac, nel corso della quale gli è stata dedicata una semplice targa. Senza alcun dubbio, Dirac è considerato dalla comunità scientifica come uno dei fisici più brillanti della storia: nel Regno Unito fa parte del trio dei grandi fisici, insieme a Newton (pilastro della meccanica) e Maxwell (colosso dell' elettromagnetismo).
I suoi lavori modificarono considerevolmente il panorama della fisica esistente ai suoi tempi e, cosa più importante, costituirono le "fondamenta" di gran parte dello sviluppo
successivo della fisica teorica. Dirac è uno dei creatori della meccanica quantistica. La sua teoria della trasformazione ingloba le due formulazioni conosciute della teoria quantistica: matriciale ed ondulatoria, che raggiunse la formulazione matematica definitiva con l' opera di John von Neumann (1903-1957). Il più grande risultato scientifico di Dirac fu lo sviluppo dell' equazione quantistica relativistica dell' elettrone e la formulazione dell' interazione radiazione-materia. Dalle equazioni di Dirac nacque il mondo delle antiparticelle e, con esso, il modo di spiegare e descrivere come la radiazione interagisca con la materia. Dalla combinazione dell' equazione quantistica relativistica dell'elettrone e della teoria quantistica della radiazione nacque l'elettrodinamica quantistica: la teoria che spiega il comportamento degli elettroni e degli antielettroni e come questi interagiscono con la luce e tra di loro. L'equazione di Dirac continua ad essere quasi una perfetta sconosciuta: si tratta di un' equazione formalmente semplice e concisa, che nasconde, però, un'autentica sorpresa. Infatti l'interpretazione delle sue soluzioni portò con sé una vera rivoluzione: l' antimateria.
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Schreiber, Matthias. "Disc accretion onto white dwarfs." Doctoral thesis, [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=961356944.
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Mehmedovic, Edin. "Värdeflödesanalys på DIAB AB Laholm." Thesis, Jönköping University, JTH, Industrial Engineering and Management, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-370.
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This report is the result of a 20-points project at the University of Jönköping. The project was carried out in form of a case study with the object of analysing the value flow at DIAB AB’s confection department in Laholm. The aim of this project is to submit proposals to the production management on how to increase the efficiency of the production flow at the confection department and reduce the capital accumulation in form of products in work.
The information in this report is gathered from interviews, observations and measurements. Furthermore, a literature study was carried out in view to find suitable theories when analysing present as well as future suggested production conditions.
This report is based on four main questions:
• What does the existing process of the value flow for the most produced product family look like?
• How does the process of the value flow for GS perform considering the through-put-time?
o How long through-put-time does a representative product of the GS-family have?
o How long is the value- and no value adding time for that product along its production flow?
• Which production related disturbances and cost prompters exist in the present value flow process?
• How could the process of the value flow for GS be made more efficient, less persistent to disturbances and more competitive?
The existing process of the value flow for the most producing product family has been mapped and is illustrated in appendix 3. For now, the process includes nine working stations along the production chain.
The through-put-time of a representative GS-product is according to my survey 18,5 days. The value adding time is only 16,1 minutes, that is 0,061 % of the entire through-put-time. The remaining time, in other words the no value adding time, is 440 hours and it represents mainly storage and transport of products.
The representative production disturbances and cost prompters that characterise the process of the value flow contain material related disturbances, a high number of long shifts, long storage time prior to the customer order point and with that, high capital accumulation and finally unnecessary transports.
Improvement proposals aim to increase the efficacy of the process of the value flow and reduce the capital amounts by shifting from the present production strategy involving manufacturing towards order (TMO) to assembling towards order (MMO).
In order to make this possible a semi-manufactured storage will be introduced after the standard confection which will represent the new decoupling point. The production at the standard confection will then occur according to the semi-manufactured storage. The standard confection should produce in larger aggregated order quantities based on prognosis in order to benefit from the advantages of economy of scale and the production must proceed in a continuous flow according to the FIFU-system (First In First Out). In addition to that, the special confection must produce according to a pull-system and only when the customer makes a request.
The tact-time of the GS products should constitute a limit for all the cycle times along the production chain, both on the standard- and special confection. This is partly due to creating a constant and balanced production flow which enables short through-put-time and partly due to avoiding in-between-storage as a result of various bottlenecks.
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Lundin, Anders. "Corticosteroids in Lumbar Disc Surgery." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6126.
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Stefanakis, Manos. "Biomechanics of intervertebral disc pain." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556723.
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'Background: Back pain is strongly (but variably) associated with degeneration of intervertebral discs. Mechanical loading has long been considered one of the causes of disc pathology and pain, but its precise role is poorly understood. In particular the spatial relation between load distribution inside the disc, the disc matrix changes as a result of load and their relationship with pain has not been researched. Methods: Distribution of compressive stress inside intervertebral discs from all regions of the spine was studied using stress profilometry in cadaveric motion segments. Matrix pathological changes were studied using simple histology and light microscopy in two groups of surgically removed discs: 'painful' discs from patients undergoing surgery for suspected discogenic pain, and 'control' discs from patients undergoing surgery for scoliosis or spondylolisthesis reduction. Ingrowth of nerves and blood vessels into the annulus was studied by immunohistochemistry with an endothelial and a general neuronal marker. Stress reduction inside annulus fissures were investigated using stress profilometry. Proteoglycan reduction within annulus fissures was studied by means of a novel, semi-quantitative method involving simple histology and image analysis. Although semi-quantitative, the technique had great spatial resolution and allowed integration with the results from the mechanical experiments. Results: High stress concentrations were localised in the middle annulus and increased with disc degeneration. Associated stress gradients appeared early in the degeneration process and were not diminished in late stage degeneration when substantial compressive loading is transferred to the neural arch. Nerve and blood vessel ingrowth increased with degeneration, but were confined to the outermost 4mm of the annulus. Other cellular changes such as apoptosis, cellular infiltration and proliferation were mostly confined to the annulus. Annulus fissures were found to represent focal regions of low proteoglycan content, and also of low compressive stress, especially when the nucleus was also decompressed. Conclusions: Results suggest that high stress gradients play an important role in progressive annulus disruption, and that annulus fissures provide a microenvironment that is mechanically and chemically conducive to the ingrowth of nerves and blood vessels. Co-localisation of nerves, blood vessels and stress concentrations in the middle-outer annulus suggest that this is the most likely site of discogenic pain. Pain is associated with annulus disruption and the attempted healing rather than age-related degenerative changes in the nucleus.
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Gustafsson, Joakim. "AUTOMATIC BRAKING DISC ANALYSIS SYSTEM." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-28217.
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Volvo Group Truck Technology has the ambition to automate parts of their routine service. Therefore a project was launched to investigate which parts of the routine that could be automated. The idea of this project is to lower the time spent on the service and also improve the working environment for the personnel. The purpose of this thesis is to develop and build a conceptional prototype for a low-cost crack detecting sensor. This thesis is a part of a larger proof of concept project which Volvo GTT runs in cooperation with Robotdalen and Robot Application Center (RAC). The work done in this thesis has been based on literature studies, interviews and company visits. The gathered knowledge and observations was translated into what would be required to fit the needs. This thesis covers different techniques that could be used to detect flaws in braking discs. However, this thesis is mostly focused on one non-destructive method technique based on induced eddy currents. Several non-destructive techniques and conceptual designs has been tested and evaluated with varying results during this project. The result of this thesis was a design that reacts to discontinuities in conductive materials, such as the grey cast iron material used in the Volvo trucks braking discs. The results are represented as a voltage drop change and can be visualized by an oscilloscope. This study shows that the method of choice has the potential to be used as a crack detecting system and that the system can be built reliable with rather cheap components. Further development should aim towards making the design even cheaper and the components should be assembled on a PCB instead of a breadboard in order to make the system less sensitive to noise and easier to assemble alongside the trucks braking discs.
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Rahimi, A. "Chemodynamical simulations of disc galaxies." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1369919/.
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We use numerical simulations to probe the evolutionary history of spiral galaxies such as our own Milky Way. We use the chemodynamical simulation code GCD+ to simulate several galaxies both in a cosmological and isolated environment. The simulations include gravity, hydrodynamics, radiative gas cooling, star formation, stellar evolution, metal production and feedback into the interstellar medium. We describe in detail how these physical processes are implemented in two different versions of the code adopted in this thesis. The simulations are compared with observations in order to disentangle the details of spiral galaxy formation. Several unresolved issues regarding the evolution of spiral galaxies are specifically addressed. We first analyse the properties of stars found in the bulge component of our simulated spiral galaxies, finding that stars formed during mergers at different epochs show different elemental abundance ratio [α/Fe]. Stars formed during one of the merger events retain a systematically prograde rotation at the present time demonstrating that ancient orbital information may still be preserved in the present day kinematics of bulge stars. Next, we analysed the radial abundance gradients along the disc, comparing with recent observations from the Milky Way. We found that the disc contains a greater fraction of young stars in the outer regions, with older stars in the inner regions. This could explain the positive [α/Fe] and negative [N/O] gradients with radius. These radial trends are a natural outcome of an inside-out formation of the disc and could thus explain the recently observed positive [α/Fe] gradients seen in Milky Way disc open clusters. Finally, several isolated galaxy evolution simulations were carried out using the new and improved version of our N-body/smoothed particle hydrodynamics code. We show that our models with higher energy feedback from supernovae and stellar winds more closely resemble the observations of spiral galaxies.
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Faridani, Jacqueline. "Dynamics of nonabelian Dirac monopoles." Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:71be8f51-cab2-48dc-bb7c-fb0274851c97.
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Ribosomal RNA genes (rDNA) exist in yeast both as a single chromosomal array of tandemly repeated units and as extrachromosomal units named 3um plasmids, although the relationship between these two forms is unclear. Inheritance of rDNA was studied using two systems. The first used a naturally occuring rDNA restriction enzyme polymorphism between two strains to distinguish between their rDNA arrays, and the second involved cloning a tRNA suppressor gene into rDNA to label individual rDNA units. An added interest to the study of the inheritance of rDNA in yeast was the possible association between it and the inheritance of the Psi factor, an enigmatic type of nonsense suppressor in yeast which shows extra-chromosomal inheritance. In a cross heterozygous for the rDNA polymorphism and the psi factor, tetrad analysis suggested that the psi factor had segregated 4:0. The majority of the rDNA units segregated in a 2:2 fashion, which suggested that reciprocal recombination in the rDNA of psi+ diploids is heavily suppressed as was previously shown for psi- diploids. A heterologous plasmid containing the tRNA suppressor gene was constructed and transformed into haploid and diploid hosts. A series of transformants was obtained and physical and genetic analysis suggested that they contained tRNA suppressor gene(s) integrated into their rDNA. In a cross heterozygous for rDNA-tRNA gene insert(s), 6% of the tetrads dissected showed a meiotic segregation of the suppressed phenotype which could most probably be accounted for by inter-chromosomal gene conversion. This observation could be interpreted in two ways. Firstly, recombination intermediates between rDNA on homologues may occur in meiosis, but they are mostly resolved as gene conversions without reciprocal cross-over. Alternatively, gene conversion tracts in rDNA are rare but very long so that the tRNA gene insert was always included in the event. 3um rDNA plasmids containing the tRNA gene marker were not detected in any of the transformants analysed. An extensive quantitative analysis of the rate of reversion of the suppressed phenotype amongst these transformants identified a particulary unstable transformant group. It was proposed that the mechanism of reversion was loss of the tRNA gene insert by unequal sisterstrand exchange, and the mechanism was shown to be independent of the recombination/repair genes RAD1, RAD52, and RAD51. A genetic analysis of stability suggested that there may have been at least two loci segregating in the host strains with additive effects on stability.
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Cooke, Adam. "Turbomachinery disc heat transfer uncertainty." Thesis, University of Sussex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442442.
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Aita, Antonello. "Fermioni di Dirac nel grafene." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7811/.
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In questo lavoro si affronta l'argomento dei fermioni di Dirac nel grafene, si procederà compiendo nel primo capitolo un'analisi alla struttura reticolare del
materiale per poi ricostruirne, sfruttando l'approssimazione di tigth-binding, le funzioni d'onda delle particelle che vivono negli orbitali del carbonio sistemate nella struttura reticolare e ricavarne grazie al passaggio in seconda quantizzazione l'Hamiltoniana. Nel secondo capitolo si ricavano brevemente le equazioni di Dirac e dopo una piccola nota storica si discutono le equazioni di Weyl arrivando all'Hamiltoniana dei fermioni a massa nulla mostrando la palese uguaglianza alla relazione di dispersione delle particelle del grafene. Nel terzo capitolo si commentano le evidenze sperimentali ottenute dalla ASPEC in cui si manifesta per le basse energie uno spettro lineare, dando così conferma alla teoria esposta nei capitoli precedenti.
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Bär, Christian. "Das Spektrum von Dirac-Operatoren." Bonn : [s.n.], 1991. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=003506032&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Rodriguez-Vega, Martin Alexander. "Disorder Effects in Dirac Heterostructures." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1477068246.
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In this dissertation, we study theoretically heterostructures based on Dirac mate- rials, i.e. materials, such as graphene in which the electrons behave as massless Dirac fermions at low energies. We first examine how the presence of long-range disorder affects the electronic ground state of a double layer graphene heterostruc- ture formed by two graphene layers separated by a thin dielectric film. We then identify the necessary conditions for the formation of an interlayer exciton conden- sate in such a system. We also comment on the effect of long-range disorder on the broken symmetry ground state induced by electron-electron interactions in bilayer graphene. Then, we study the transport properties of heterostructures obtained by stacking a graphene layer on the surface of a strong three-dimensional topological insulator (TI). In particular, we determine the non-equilibrium current-induced spin density accumulation for these systems using linear response theory and taking into account the effects of long- and short-range disorder both in the limit of strong and weak tunneling between the graphene layer and the TI. Finally, using some of the theoretical approaches developed to characterize the effect of long-range disorder in Dirac materials, we study the effect of long-range inhomogeneities in first-order phase transitions. In particular, we present a theoretical model to describe the ef- fect of inhomogeneities on the relaxation dynamics of vanadium dioxide films after a photo-induced metal-insulator transition.