Made available in DSpace on 2015-04-14T13:58:56Z (GMT). No. of bitstreams: 1 445009.pdf: 223720 bytes, checksum: d3c1269b971aa018e0749ec69ef77b3e (MD5) Previous issue date: 2012-10-31 / Commercial processes to capture CO2, are mostly, are based on chemical absorption by amine solutions, though this technique promotes the efficient CO2 separation this has disadvantages such as loss of volatile amines and their degradation. Alternatives have been studied for carbon capture and ionic liquids (RTILs) and poly (ionic liquids) - p(IL)s, are indicated in the literature as materials with a capacity to solubilize gases. In these studies CO2 shows has a high solubility in comparison to other gases, proving to be an alternative to carbon capture techniques already used industrially, in order to mitigate environmental impacts. This work aims to synthesize and characterize new poly(ionic liquid)s, and verify the CO2 solubility in these products, compared with modified RTILs and p(IL)s already presented in the literature. The p(IL)s synthesis were based on polyurethanes, because they present structures highly nitrogenous. The synthesized materials were characterized according to its structure, composition, thermal stability, and morphology by techniques such as FTIR, 1H-NMR, TGA, DSC, GPC and SEM. The CO2 solubility measurements were determined using a thermogravimetric microbalance high pressure (PTGA) at 25 ? C, as well as in a equilibrium cell for verifying the integrity of samples during the tests of solubility. In This study was observed better absorption capacity of the p(LI)s compared to the RTILs, demonstrating to be compatible with the literature, and the PUA-02a presented the best results, promising ones for use in CO2 capture. / Os processos para captura de CO2, na sua maioria, baseiam-se na absor??o qu?mica por solu??es de aminas, apesar desta t?cnica promover a separa??o eficiente do CO2, esta possui desvantagens como a perda de aminas vol?teis e a sua degrada??o. S?o estudadas alternativas para a captura de carbono e os l?quidos i?nicos (LIs) e poli(l?quidos i?nicos) - p(LI)s s?o apontados na literatura como materiais com capacidade de solubilizar gases. Nestes estudos o CO2 apresenta alta solubilidade em compara??o com outros gases, demonstrando ser uma alternativa para as t?cnicas de captura de carbono j? utilizadas industrialmente, visando a mitiga??o dos impactos ambientais. Este trabalho tem por objetivo sintetizar e caracterizar novos poli(l?quidos i?nicos), e verificar a solubilidade do CO2 nestes produtos, comparando com LIs modificados e p(LI)s j? apresentados na literatura. As s?nteses dos p(LI)s foram baseadas em poliuret?nos, por estes apresentarem estruturas altamente nitrogenadas. Os materiais sintetizados foram caracterizados quanto a sua estrutura, composi??o, estabilidade t?rmica e morfologia por t?cnicas de IV, RMN-1H, TGA, DSC, GPC e MEV. As medidas de solubilidade de CO2 foram determinadas empregando uma microbalan?a termogravim?trica de alta press?o (PTGA), na temperatura de 25 ?C, bem como em uma c? lula de equil?brio para verifica??o da integridade das amostras durante os testes de solubilidade. Neste estudo foi observado melhores capacidades de absor??o dos p(LI)s em rela??o aos LIs, demonstrando estarem compat?veis com a literatura, sendo o PUA-02a o que apresentou melhores resultados, promissores para uso em captura de CO2.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-11-17T17:04:10Z No. of bitstreams: 1 TES_ARIELA_MILBRATH_CARDOSO_COMPLETO.pdf: 5243886 bytes, checksum: f7d5c5963bb3a8537909fa88fd5d1e20 (MD5) / Made available in DSpace on 2016-11-17T17:04:10Z (GMT). No. of bitstreams: 1 TES_ARIELA_MILBRATH_CARDOSO_COMPLETO.pdf: 5243886 bytes, checksum: f7d5c5963bb3a8537909fa88fd5d1e20 (MD5) Previous issue date: 2016-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The development of new composite materials with adsorption capacity and photodegradation become an increasing need for environmental pollution control. This thesis describes the development of composite type zeolite /TiO2/TiO2-Fe+3 and bioplastic composites, for use in the photodegradation of methylene blue and adsorption with n-butanol vapor photodegradation. The synthesis of composite type zeolite/TiO2/TiO2-Fe+3 was carried out by two distinct routes: mechanical mixing and sol-gel. For the synthesis of bioplastic composite was used biopolymer polylactic acid (PLA) via the solvent evaporation technique. The materials were characterized by various techniques: XRD, FEG-SEM-EDS, TEM, NMR, FTIR, TGA, DSC, N2 physisorption, SAXS, Raman. FEG-SEM results and NMR composite type zeolite/TiO2/TiO2-Fe+3 indicate a small dealuminization of zeolite, and high degree of coverage of the surface by nanoparticle TiO2/TiO2-Fe+3 through the synthesis method sol-gel. The photodegradation of methylene blue by composite zeolite/TiO2/TiO2-Fe+3 was more than 95% in ultraviolet radiation, ion doping with Fe+3 semiconductor allowed activation with visible radiation. The bioplastic composites had lower crystallinity degree of the pure PLA. Equilibrium adsorption of n-butanol (Ci = 3500 ppmv, odor level 5) in the bioplastic composite was achieved between 40-50 min for all samples tested, with a removal percentage of between 54-72%. The photodegradation with visible radiation was observed after 45 min illumination system, the formation of CO, CO2 and short chain oxygenates was confirmed by gas chromatography. These results suggest that the compounds synthesized in this work have potential applications for the tested. / O desenvolvimento de novos materiais comp?sitos com capacidade de adsor??o e fotodegrada??o se torna uma necessidade cada vez maior para o controle da polui??o ambiental. Este trabalho relata o desenvolvimento de comp?sitos do tipo ze?lita/TiO2/TiO2-Fe+3 e comp?sitos de biopl?stico, para aplica??o em fotodegrada??o de azul de metileno e adsor??o/fotodegrada??o de vapor de n-butanol. A s?ntese dos comp?sitos ze?lita/TiO2/TiO2-Fe+3 foi realizada por duas rotas distintas: mistura mec?nica e sol-gel. Para a s?ntese dos comp?sitos de biopl?stico foi utilizado o biopol?mero poli ?cido l?ctico (PLA) via t?cnica de evapora??o de solvente. Os materiais foram caracterizados atrav?s de diversas t?cnicas: DRX, FEG-MEV-EDS, MET, RMN, FTIR, TGA, DSC, Fisissor??o de N2, SAXS, Raman. Resultados de FEG-MEV e RMN dos comp?sitos ze?lita/TiO2/TiO2-Fe+3 indicam uma pequena desaluminiza??o da ze?lita, e alto grau de recobrimento de sua superf?cie pelas nanopart?culas de TiO2/TiO2-Fe+3 atrav?s do m?todo de s?ntese sol-gel. A fotodegrada??o do azul de metileno obtida pelos comp?sitos ze?lita/TiO2/TiO2-Fe+3 foi superior a 95% com radia??o ultravioleta, a dopagem com ?ons Fe+3 permitiu a ativa??o do semicondutor com radia??o vis?vel. Os comp?sitos de biopl?stico apresentaram grau de cristalinidade inferior ao PLA puro, devido ? incorpora??o de cargas. O equil?brio de adsor??o de n-butanol (Ci = 3500 ppmv, odor n?vel 5) nos comp?sitos de biopl?stico foi atingido entre 40-50 min para as amostras testadas, com um percentual de remo??o entre 54-72%. A fotodegrada??o com radia??o vis?vel foi observada ap?s 45 min de ilumina??o do sistema, a forma??o de CO, CO2 e oxigenados de cadeia curta foi confirmado por cromatografia gasosa. Estes resultados sugerem que os comp?sitos sintetizados neste trabalho, apresentam potencial para as aplica??es testadas.

The expansion of prison privatisation presents distinctive traits. One of them is its peculiar temporal expansion in a comparative point of view. This research focuses on the intrastate temporal expansion and more specifically in the case of England and Wales. What is researched is the reason behind the delay in the emergence of prison privatisation, in other words the asynchrony between the introduction of general and prison privatisation policies. This Thesis rejects explanatory frameworks based on historical analogies, pragmatic concerns or economic arguments and puts the explanation in a discourse of political interaction. In this framework, previous approaches related to the concept of globalisation, commodification of citizenry and political culture do not provide either suitable analytical tools in explaining the asynchrony in question. This research, instead, aims to bring forward the class struggle as catalytic agent in criminal justice system developments using a Structural Marxist concept of the State and its transformations. In the Capitalist Mode of Production the State acquires a unifying role among the contradicting classes by promoting the supposed general interest of the society, in order to allow the continuation of class domination and labour exploitation. This is feasible through the constantly unfolding hegemonic strategy which organizes the cohesion of the power bloc and disorganizes the dominated classes. Hegemonic strategy substantiates in the State Apparatuses which is not just a tool for policy making but rather a point where contradicting class powers condense; policy formation as such reflects the vector of class power in the apparatuses. Hegemonic strategy is set in motion by the State Personnel which is relatively independent knot in the transmission of domination between the power bloc and the dominated classes. State transformations are indications of this strategy since they inscribe in the structure of the State the vector of the class struggle. Hegemonic strategy took interesting contours after the mid-‘60s. The capital over-accumulation crisis on the one hand and on the other Authoritarian Statism promoted extensive State transformations as in the case of privatisations. Massive reactions, however, caused by the labour movement, required their containment and consequently a smoothly operating criminal justice system. The entrenchment of prison officers, therefore, from the wider changes in the labour status became crucial and a state transformation in itself, although by absence. This explains the delay of prison privatisation which appears indeed at the end of a long socially unstable period.

Zugl.: Frankfurt (Main), Univ., Diss., 2007

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2015. / Made available in DSpace on 2016-05-24T17:35:15Z (GMT). No. of bitstreams: 1 338247.pdf: 926191 bytes, checksum: 3384a7c24d39065355b9c67ae64f9680 (MD5) Previous issue date: 2015 / As Centrais de Abastecimento (CEASA) constituem importantes locais geradores de resíduos de frutas e verduras (RFV), passíveis de serem tratados por processos de Digestão Anaeróbia (DA) objetivando a geração de biogás. Atualmente observa-se um aumento de interesse no processo de codigestão anaeróbia (coDA), digestão simultânea de dois ou mais substratos de diferentes origens devido à vantagens em relação à monodigestão anaeróbia como: melhorias na relação nutricional e na relação carbono/nitrogênio, diluição de compostos tóxicos e inibidores e maiores rendimentos na produção de biogás. Paralelamente, também observa-se um crescente interesse em modelagem matemática destes processos, visando a diminuição do número de ensaios necessários para testar as várias possibilidades de misturas de resíduos, sendo o Anaerobic Digestion Model no 1 ? ADM1 um dos modelos mais importantes no que tange a modelagem de digestão anaeróbia. O objetivo deste trabalho é avaliar o potencial para a geração de biogás de RFV codigeridos com lodos de esgoto (LE) mediante ensaios de potencial de produção de biogás (PPB) e a utilização dos dados obtidos num modelo matemático de coDA destes resíduos baseado no ADM1. Os ensaios de PPB foram realizados em tubos eudiômetros que medem a variação volumétrica de gás gerado e o modelo ADM1 foi implantado no programa AQUASIM. O PPB, em função de sólidos voláteis alimentados, da monodigestão anaeróbia dos RFV e LE foram de 689,37 mLN/gSV e 389,97 mLN/gSV respectivamente. O ensaio de coDA na proporção em SV de 12,5:87,5 / RFV:LE, gerou um volume de biogás 7% superior em relação ao proporcional da monodigestão anaeróbia destes resíduos, em outras proporções de mistura avaliadas não foram observados crescimentos absolutos. Os ensaios mostraram que o aumento na geração de biogás é devido ao aumento da fração orgânica biodegradável proporcionada pelos resíduos de frutas e verduras. O modelo ADM1 utilizado para simular a coDA pôde ser calibrado mediante a metodologia proposta e reproduziu satisfatoriamente os resultados experimentais constituindo uma ferramenta que pode ser utilizada para estudos diversos como estudos de efeitos inibitórios e toxinas, controle e operação, estudos em regime dinâmico, comportamento do sistema perante oscilações, entre outros.<br> / Abstract : The Brazilian state-owned companies of distribution centres for vegetables and fruits, Centrais de Abastecimento - CEASA, are important generators of fruits and vegetable wastes (FVW), which can be treated by anaerobic digestion (AD) processes for biogas production. Currently there has been an increased interest in Anaerobic Co-digestion (AcoD) processes, the simultaneous digestion of two or more substrates from different sources because the existence of advantages in relation to anaerobic monodigestion like: improvements in nutritional ratio and the carbon/nitrogen ratio, dilution of toxic compounds and inhibitors and higher yields of biogas production. At the same time also exist a growing interest in mathematical modeling of these processes to reduce the number of tests needed to evaluate the various possibilities of combinations of wastes, and the Anaerobic Digestion Model 1 - ADM1 is one of the most widely used models regarding the modeling of anaerobic digestion. The objective of this study is to evaluate the biochemical biogas potential (BBP) of the co-digestion of FVW with sewage sludge (SS) by biogas potential tests and the use of data in a model of AcoD of these wastes based on ADM1. The BBP tests were performed in eudiometer tubes that measure the volumetric change of generated gas and ADM1 model was implemented in AQUASIM software. The BBP, based on volatile solids feeded, of the anaerobic monodigestion of FVW and SS was 689,37 mLn/gvs and 389,97 mLn/gvs respectively. The AcoD BBP test of the fraction 12.5: 87.5 / FFW:SS in VS basis, generated 7 % more biogas that the proportional obtained in anaerobic monodigestion. In the other trials were not observed absolute growth. The tests showed that the increase in biogas generation is due to the increase of the biodegradable organic fraction provided by FVW. The ADM1 model used to simulate the AcoD could be calibrated by the proposed methodology and satisfactorily reproduced the experimental results. The obtained model can be a tool for many future studies such as studies and inhibitory effects of toxins, control and operation studies dynamic system, system performance under oscillation and others.

Made available in DSpace on 2014-12-17T14:13:59Z (GMT). No. of bitstreams: 1 GardeniaMHF.pdf: 1889124 bytes, checksum: 521dae16063d838bbca29f457e622890 (MD5) Previous issue date: 2004-12-10 / Objetivo: Verificar a a??o da cafe?na no tempo de rendimento, a taxa de esfor?o percebido (RPE), os n?veis plasm?ticos de glicose, s?dio e pot?ssio, a temperatura timp?nica (Tt), o peso corporal (PC), freq??ncia card?aca (FC) e concentra??o urin?ria da cafe?na com a ingest?o de doses de 5 e 9 mg/kg de cafe?na e placebo, em provas cicl?sticas sob condi??es de alto risco t?rmico. M?todos: Foram estudados 8 ciclistas treinados e aclimatizados em 3 provas de 45 km utilizando o modelo experimental e duplo-cego com randomiza??o intra-sujeitos. Resultados: N?o foram observadas diferen?as significativas entre as vari?veis avaliadas, entretanto o tempo de rendimento e a RPE foram menores com as doses de 5 e 9 mg/kg de cafe?na que com a dose placebo. Conclus?es: Estes dados indicam que as condi??es de calor e umidade podem ser suficientes para mascarar o benef?cio ergog?nico da cafe?na, entretanto deve-se considerar que a cafe?na pode exercer influencia sobre a percep??o subjetiva de esfor?o podendo levar ? redu??o dos sinais de fadiga durante o exerc?cio e conseq?ente melhora do desempenho esportivo

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-11-27T13:08:55Z No. of bitstreams: 1 AseneteFrutuosoDaCosta_TESE.pdf: 4115238 bytes, checksum: 72a04780a21fa7344d83533cdbdd3d36 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-11-27T14:44:06Z (GMT) No. of bitstreams: 1 AseneteFrutuosoDaCosta_TESE.pdf: 4115238 bytes, checksum: 72a04780a21fa7344d83533cdbdd3d36 (MD5) / Made available in DSpace on 2015-11-27T14:44:06Z (GMT). No. of bitstreams: 1 AseneteFrutuosoDaCosta_TESE.pdf: 4115238 bytes, checksum: 72a04780a21fa7344d83533cdbdd3d36 (MD5) Previous issue date: 2014-08-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Dentre os principais pigmentos, os materiais cer?micos que possuem a estrutura espin?lio AB2O4 v?m se tornando objeto de grande interesse cient?fico e tecnol?gico devido ? capacidade em acomodar diferentes c?tions em sua estrutura, permitindo diferentes tipos dopagens e, consequentemente, a obten??o de diferentes cores. Estudos sobre pigmentos cer?micos, atualmente, v?m sendo direcionados para o desenvolvimento de pigmentos est?veis e obtidos a baixas temperaturas e com maior reprodutibilidade. O objetivo do seguinte estudo ? a utiliza??o de pigmentos inorg?nicos para aplica??es em revestimentos cer?micos, tentando compreender quais par?metros influenciam na colora??o do pigmento nos esmaltes cer?micos. Pigmentos a base de CoCr2O4, CoAl2O4, Co0,8Zn0,2Cr2O4 e Co0,8Zn0,2Al2O4Co/Cr, foram sintetizados por uma rota qu?mica usando gelatina como precursor org?nico. Tais pigmentos foram caracterizados por An?lise termogravim?trica, Difra??o de raios X (DRX), Espectroscopia na regi?o do Infravermelho, Microscopia eletr?nica de varredura (MEV) Espectroscopia na regi?o do UV-Vis?vel e Colorimetria. Os resultados confirmaram a viabilidade da rota de s?ntese utilizada; com rela??o aos p?s sintetizados, Os pigmentos mostraram-se cristalinos e as fases desejadas foram obtidas a partir de 500oC, com um aumento da cristalinidade, assim como o tamanho m?dio de cristalito. Os pigmentos possuem tonalidades que v?o do verde ao violeta de acordo com as dopagens e suas temperaturas de calcina??o. / Ceramic pigments that own mainly the spinel structure AB2O4 are becoming a matter of great scientific and technological interest due to the ability of accommodate different cations in its structure, allowing different dopings and thus obtaining different colors. Studies on ceramic pigments currently are being directed to the development of stable and pigments obtained at low temperatures and with greater reproducibility. This work aims at the use of inorganic pigments for applications in ceramic tiles, investigating the influence of doping and calcination temperature on the coloring pigments and ceramic glazes. the based pigments of CoCr2O4, CoAl2O4, Co0,8Zn0,2Cr2O4 and Co0,8Zn0,2Al2O4 were synthesized by a chemical route using commercial gelatin as organic precursor. The materials were characterized by thermogravimetric analysis (TG), X-ray diffraction (XRD), infrared spectroscopy (FTIR) spectroscopy scanning electron microscopy (SEM) in the UVVisible region and colorimetry. The results confirmed the feasibility of synthesis used, the route presented pigments crystal structures and the desired phases were obtained from 500 ?C with increased crystallinity and the crystallite size. The pigments have hues ranging from green to violet according to their doping and calcination temperatures.

Made available in DSpace on 2015-04-14T13:56:32Z (GMT). No. of bitstreams: 1 462535.pdf: 2831098 bytes, checksum: 68e2e14cae00038d54ccc16f10fe2911 (MD5) Previous issue date: 2014-08-21 / Auto guided vehicles are robots capable of moving in an intelligent way in order to accomplish different tasks. Nowadays, researches not only aiming industry operation, but also vehicles that may act in hostile environments, either complex or even with more skills and strenght than a human being are being developed everywhere in the world. These vehicles need not only a smart way of displacement, but also need sensors capable of sensing changes in the environment and locate the device with success. This work develops an Omni-Directional vehicle - a vehicle capable of displacement in an XY plane without changing its original orientation and also capable of rotating about its own axis - going from the development of its mathematical model to the control strategy of the trajectory, going through sensoring via Visual Servoing and inertial sensors fused with a Kalman Filter. Also, a prototype was used in experiments for comparison with simulations performed in a virtual environment. / Ve?culos auto guiados s?o rob?s capazes de se deslocar de maneira inteligente afim de cumprir diversas tarefas. Atualmente, pesquisas voltadas n?o somente para a opera??o em ind?strias, mas tamb?m para ve?culos que possam atuar em ambientes in?spitos, complexos ou mesmo com mais agilidade e for?a que um ser humano est?o sendo desenvolvidas em toda a parte do mundo. Esses ve?culos necessitam n?o s? de uma maneira inteligente de se locomover, mas precisam tamb?m de sensores capazes de perceber mudan?as no ambiente e realizar sua localiza??o com sucesso. Este trabalho desenvolve um ve?culo Omni-Direcional - ve?culo capaz de se movimentar em um plano XY mantendo sua orienta??o inicial e tamb?m capaz de rotacionar em seu pr?prio eixo - tratando desde seu modelamento matem?tico, at? o controle de sua trajet?ria, passando pelo sensoriamento utilizando um sensor de vis?o e um sensor inercial com um Filtro de Kalman Extendido para realizar a fus?o destas informa??es. Ser? aplicado um controlador n?o-linear de tempo ?timo denominado PTOS em cada um de seus graus de liberdade. Para isso, um prot?tipo foi utilizado para ensaios reais e compara??o com simula??es feitas em um ambiente virtual.

Made available in DSpace on 2015-04-14T14:41:29Z (GMT). No. of bitstreams: 1 435711.pdf: 4891064 bytes, checksum: 03dd73d1fd3e3a907147a4099297028d (MD5) Previous issue date: 2011-12-21 / With people spending billions of hours every week playing games, often in multiplayer games, video games have become an extremely important medium for communication and interaction. Many game studies focus on their highest contextual level: their reception and operation by their users. This dissertation proposes an alternate method, a study of the lowest level: the hardware and software platforms which execute video games. By turning our attention away from the final user and focusing on the technological context, we begin to understand how the technologies are appropriated by game developers to enable new forms of socializing inside their games. This dissertation presents the results of a historic-comparative study of the social interactions inside video games throughout their history. From the results, we have extracted a set of variables which define the different forms of social gameplay inside games, and we have categorized the technologies which impact social gameplay. Based on this analysis, we propose a way for the platform creators to plan their technological development and for developers to think of other ways to appropriate technologies and create new types of social gameplay. / Com jogadores dedicando bilh?es de horas por semana na pr?tica de jogos digitais, muitas vezes em partidas de m?ltiplos jogadores, os jogos tornaram-se um meio de comunica??o e intera??o de alta relev?ncia. Muitos estudos dos jogos digitais focam no n?vel mais alto do seu contexto: a recep??o e opera??o pelos usu?rios. Esta disserta??o prop?e um caminho alternativo, o estudo do n?vel mais baixo: as plataformas de hardware e software que executam os jogos digitais. Ao desviar a nossa aten??o do usu?rio final para olhar o contexto tecnol?gico, come?amos a entender como as tecnologias s?o apropriadas pelas empresas desenvolvedoras de jogos digitais para habilitar novas formas de sociabilidade dentro dos jogos. Esta disserta??o exp?e os resultados de uma pesquisa comparativa-hist?rica das intera??es sociais oferecidas dentro dos jogos digitais ao longo da sua hist?ria. Dos resultados, extra?mos um grupo de vari?veis que definem as formas de jogabilidade social dentro dos jogos, e conseguimos categorizar as tecnologias que impactam a jogabilidade social. Com esta an?lise, propomos uma maneira para os criadores de plataformas planejarem o seu desenvolvimento tecnol?gico e para as desenvolvedoras pensarem em outras maneiras de apropriar tecnologias para criar novas jogabilidades sociais.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-11T17:13:30Z No. of bitstreams: 1 EduardoAlonsoCruzMonroy_DISSERT.pdf: 2026837 bytes, checksum: 07d08221eedeeea6100a427aaf6ca1d9 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-14T17:30:27Z (GMT) No. of bitstreams: 1 EduardoAlonsoCruzMonroy_DISSERT.pdf: 2026837 bytes, checksum: 07d08221eedeeea6100a427aaf6ca1d9 (MD5) / Made available in DSpace on 2016-07-14T17:30:27Z (GMT). No. of bitstreams: 1 EduardoAlonsoCruzMonroy_DISSERT.pdf: 2026837 bytes, checksum: 07d08221eedeeea6100a427aaf6ca1d9 (MD5) Previous issue date: 2016-02-26 / Les?es odontog?nicas epiteliais benignas s?o entidades de grande import?ncia cl?nica que se desenvolvem nos ossos maxilares a partir dos tecidos que formam os dentes. Tem sido demonstrado que em tumores benignos e malignos, est?o presentes um grande n?mero de c?lulas tronco tumorais, as quais tem grandes implica??es no desenvolvimento dos tumores. Oct-4 e CD44 t?m sido demostrados como importantes marcadores para c?lulas-tronco tumorais. O objetivo deste estudo foi identificar c?lulas epiteliais que expressam marcadores de c?lulas tronco atrav?s da express?o imuno-histoqu?mica de Oct-4 e CD44 em uma s?rie de casos de les?es odontog?nicas epiteliais ben?gnas. A amostra foi constitu?da por 20 casos de ceratocisto odontog?nico (CCO), 20 caos de Ameloblastoma s?lido/multic?stico e 20 casos de Tumor Odontog?nico Adenomatoide (TOA). A express?o de Oct-4 e CD44 foi avaliada no epit?lio das les?es atrav?s do percentual de c?lulas positivas(PP) e da intensidade da express?o ( IE ), sendo realizado o somat?rio destes escores, resultando na Pontua??o de Imunomarca??o Total (PIT) que variou de 0 a 7. Os resultados do presente estudo foram analisados pelo valor da pontua??o de PIT. Todos os casos apresentaram positividade para os dois marcadores e a maioria exibiu alta express?o para ambos os marcadores. A an?lise da express?o de Oct-4 n?o revelou diferen?as estatisticamente significativas (p = 0,406) entre as les?es estudadas. Com rela??o ? express?o do CD44, houve diferen?a estatisticamente significativa entre os casos de ameloblastoma e CCO, apresentando este ?ltimo maior n?mero de casos no score 7 (p = 0,034). Na analise da correla??o da imunoexpress?o de ambos os marcadores nas tr?s les?es estudadas, n?o houve correla??o estatisticamente significativa . Os resultados do presente estudo identificaram a presen?a de c?lulas com caracter?sticas troncais dispostas em locais variados do componente epitelial das les?es ora estudadas sugerindo a sua poss?vel participa??o na histog?nese e diferencia??o em les?es odontog?nicas epiteliais benignas contribuindo assim para o desenvolvimento destas les?es. / benign epithelial odontogenic lesions are great clinical importance entities that develop in the jaws from the tissues that form teeth. It has been shown that in benign and malignant tumors, are present in a large number of tumor stem cells, which has great implications in the development of these lesions. Oct-4 and CD44 have been demos as important markers for tumoral stem cells. The objective of this study was to identify epithelial cells expressing stem cell markers by immunohistochemical expression of Oct-4 and CD44 in a series of cases of benign epithelial odontogenic lesions. The sample was comprised of 20 cases of odontogenic keratocyst (OKC), 20 cases of solid/multicystic ameloblastoma and 20 cases of adenomatoid odontogenic tumor (AOT). The expression of Oct-4 and CD44 was evaluated in epithelial lesions using the percentage of positive cells (PP) and the intensity of expression (IE), being realized the sum of these scores, resulting in Total Immunostaining Score (TIS) ranging 0 to 7. The results were submitted to the appropriate statistical test (nonparametric Kruskal-Wallis and Spearman correlation coefficient). All cases were positive for both markers and most showed high expression of both markers. The analysis of Oct-4 expression revealed no statistically significant differences (p = 0.406) among the studied lesions. Regarding the CD44 expression, there was a statistically significant difference between the cases of ameloblastoma and TOA in relation to the CCO, with the latter show more cases in the score 7 (p = 0.034). In the correlation analysis of the immunoreactivity of both markers in the three lesions studied, there was no statistically significant correlation. The results of this study identified the presence of cells with stemness characteristics arranged at various sites in the epithelial component of the studied lesions suggesting their possible role in the histogenesis and differentiation in benign epithelial odontogenic lesions, thus contributing to the development of these lesions.