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Análise fractográfica e de resistência mecânica de duas marcas de placas de titânio em fraturas simuladas em corpo de hemimandíbulas de alumínio / Fractographic and mechanical analysis of two brands of titanium plates in simulated body fractures of aluminum hemimandiblesMoura, Andrezza Lauria de, 1982- 06 April 2013 (has links)
Orientadores: Marcelo Marotta Araújo, Roger William Fernandes Moreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-23T00:56:38Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: O propósito no estudo foi avaliar comparativamente, através de teste de carregamento linear e análise fractográfica, duas marcas de material de fixação interna estável com dois métodos de fixação em fraturas simuladas em corpo de hemimandíbulas de alumínio. O trabalho foi dividido em dois grupos: Grupo I com duas estruturas de alumínio semelhantes à hemimandíbulas e fixação com duas placas de titânio de quatro furos do sistema 2,0mm, sendo uma placa na zona de compressão e outra zona de tensão, totalizando 20 placas de titânio; e grupo II, com duas estruturas de alumínio semelhantes à hemimandíbulas e fixação de uma placa de titânio de quatro furos do sistema 2,0mm na zona neutra de corpo de mandíbula, totalizando 10 placas de titânio. Testes de carregamento linear foram realizados por meio da máquina para ensaio universal mecânica Instron®, até a fratura do material. Após os testes, foram realizadas as análises fractográficas das superfícies de fratura dos materiais de fixação (grupos I e II) através de microscópio eletrônico de varredura FEI®, com o objetivo de analisar orientações, texturas e falhas dos materiais. Médias e desvio padrão das cargas e deslocamentos foram avaliados aplicando-se a Análise de Variância (ANOVA) two-way e teste de Tukey em nível de significância de 5%. Os resultados mostraram que o método de fixação com duas placas retas de quatro furos apresentou maior resistência à carga (p<0,01), quando comparado ao grupo de apenas uma placa de titânio na zona neutra mandibular. Ainda, a marca Traumec® apresentou maior resistência mecânica (p<0,01) quando utilizada no método com duas placas de fixação e a marca Tóride® (p<0,01) apresentou maior resistência as carga quando utilizada no método com apenas uma placa de fixação. A fractografia informou que todas as fraturas ocorreram por sobrecarga dúctil e micromecanismo alveolar / Abstract: The purpose of the study was to comparatively evaluate, through linear load test and fractographic analysis, two brands of stabel internal fixation in two methods of fixation in simulated body fractures in aluminium hemimandibules. The study was divided into two groups: Group I with two aluminum structures similar to hemimandibles for fixation of one 2,0mm miniplate in the compression zone and another one in tension zone, totaling 20 miniplates; and group II, with two aluminum structures similar to hemimandibles for fixation of one 2,0mm miniplate in the neutral zone of the mandible, totaling 10 miniplates. Mechanical tests were performed via mechanical universal testing machine Instron¿ until complete failure of the material. After the tests, fractography analysis of fractured surfaces were done in all materials (groups I and II) by a FEI¿ scanning electron microscopy, with the objective of analyzing orientation and textures of materials failures. Means and standard deviations of load and displacement were evaluated by applying the analysis of variance (ANOVA) two-way and the Tukey test at a significance level of 5%. The results showed that the method of fixation with two titanium plates with four holes showed higher resistance loads (p<0,01), when compared to only one titanium plate in the neutral zone of the mandible. Furthermore, the brand Traumec¿ showed higher mechanical strength (p<0,01) when used in the method with two fixing plates and the brand Toride¿ (p<0,01) showed a higher resistance to loads when used in the method with only one miniplate. The fractography reported that all fractures occurred in ductile overload and alveolar micromechanisms / Mestrado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Mestra em Clínica Odontológica
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Estudo mecânico e microestrutural em dois sistemas de fixação interna usados em osteotomia sagital mandibular / Mechanical and microstructural evaluation of two internal fixation systems used in mandibular sagittal split ramus osteotomyMendes, Marcelo Breno Meneses, 1984- 24 August 2018 (has links)
Orientador: Roger William Fernandes Moreira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-24T03:19:50Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: O objetivo deste estudo foi avaliar, através da análise de rugosidade superficial, microscopia eletrônica de varredura (MEV), análise de composição através de espectroscopia de raios-X e análise de resistência mecânica, dois diferentes sistemas de fixação interna usados em fixação de osteotomia sagital do ramo mandibular. Foram selecionadas cinco placas retas do sistema 2,0 mm com quatro furos e 20 parafusos de 6 mm de comprimento de dois sistemas de fixação interna, grupo I: Tóride (Tóride Indústria e Comércio Ltda. -Mogi Mirim, São Paulo -Brasil) e grupo II: Medartis (Medartis AG -Basel, Suíça). Para os testes mecânicos, foram selecionadas dez hemimandíbulas de poliuretano, dividindo-as igualmente entre os grupos I e II. Inicialmente, foi realizada análise de rugosidade superficial em todas as placas dos dois sistemas, e os dados foram submetidos à análise de variância e teste de Tukey (p>0,05) para a comparação entre as médias. Em seguida, as mesmas placas foram avaliadas no espectrômetro por meio de difração de raios-X e logo após foram analisadas no MEV. Por último, foi realizado o teste mecânico, no qual as hemimandíbulas de poliuretano foram fixadas e submetidas ao teste de carregamento (1mm/min). Os dados foram analisados quanto à carga de pico (em Newtons) e o deslocamento de pico (em mm) para todos os grupos estudados, e posteriormente submetidos ao teste t. Os grupos testados apresentaram vestígios superficiais dos processos de usinagem, principalmente nas margens dos elos. O grupo II apresentou revestimento com uma camada de nitreto de titânio. A análise da rugosidade revelou diferença entre as regiões de centro e margem da placa para o grupo I; diferente do grupo II, o qual apresentou valor de rugosidade menor e mais uniforme. O teste mecânico revelou que o grupo II apresentou maior carga de pico. Os dados demonstraram que há diferença microestrutural e mecânica entre os grupos testados. / Abstract: The aim of this study was to evaluate, through surface roughness analysis, scanning electron microscopy (SEM), composition analysis by X-ray spectroscopy and analysis of mechanical strength, two different systems used in internal fixation of mandibular sagittal split osteotomy fixation. Five straight 2.0 mm system plates with four holes and 20 screws 6 mm length of two internal fixation systems were selected, group I: Toride (Toride Indústria e Comércio Ltda -Mogi Mirim, São Paulo -Brazil.) and group II: Medartis (Medartis AG -Basel, Switzerland). For mechanical testing, ten polyurethane hemimandibles were used, distributing them equally into groups I and II. Initially, surface roughness analysis was performed on all plates of the two systems, and the data were subjected to analysis of variance and Tukey's test (p> 0.05) for comparison between means. Then, the same plates were evaluated in the spectrometer by means of X-ray diffraction and after this evaluation, they were subjected to SEM. Finally, mechanical testing was performed, in which the polyurethane mandibles were fixed and subjected to the load (1mm/min) test on an Instron testing machine, Model 4411 (Instron Corp., Norwood, MA). Data were analyzed for peak load (in Newtons) and peak displacement (in mm) for all groups, and then subjected to t test. The groups tested showed superficial traces of machining processes, especially on links periphery. Group II had coated with a layer of titanium nitride. The roughness analysis revealed differences among the regions of the center and edge of the plate for group I; group II showed roughness value smaller and more uniform, than group I.The mechanical test showed that group II had higher peak load. The data demonstrated that there are microstructural and mechanical differences between the tested groups. / Doutorado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Doutor em Clínica Odontológica
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Estudo das complicações no tratamento das fraturas transtrocanterianas do fêmur utilizando pino deslizante extramedular com técnica minimamente invasiva, Sistema Minus / Treatment of transtrochanteric fractures of the femur complications associated with the use of extramedullar slidind pin and minimally invasive Minus System techiqueSawaia, Rogerio Naim, 1970- 19 August 2018 (has links)
Orientador: William Dias Belangero / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T13:05:04Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: INTRODUÇÃO: O tratamento cirúrgico das fraturas intertrocanterianas do fêmur ainda é motivo de estudo e controvérsias. As vantagens da utilização de técnicas minimamente invasivas para essas fraturas já despontam na literatura. O objetivo deste estudo foi avaliar as complicações da técnica minimamente invasiva que utiliza um implante e um instrumental desenvolvidos especificamente (Sistema Minus) para o tratamento dessas fraturas. CASUÍSTICA E MÉTODO: Foram estudados 172 pacientes com fratura intertrocanteriana do fêmur, tratados com o Sistema Minus, dos quais 52 pacientes foram excluídos do estudo por não terem preenchido os critérios de inclusão. No protocolo inicial foram registrados o gênero, a idade, detalhes operatórios como tempo cirúrgico, tempo de uso da fluoroscopia, qualidade da redução e da fixação da fratura. Como parâmetros clínicos foram incluídos a capacidade de marcha, dor, classificação da fratura segundo os critérios de Tronzo e o risco anestésico segundo a classificação de ASA. Dividimos as complicações em dois grupos. As complicações gerais, subdivididas em infecção e mortalidade e as complicações específicas, subdivididas em migração do implante, a perda da redução e a falta de união. Embora a migração do pino deslizante não seja considerada na literatura como uma complicação do DHS (Hrubna e Skotak, 2010)1, no presente estudo ela foi incluída. Cabendo salientar que foi considerada como migração, a impacção lateral da fratura sem a ocorrência de perda de redução. RESULTADOS: O gênero feminino ocorreu em 93 casos e obteve percentual de 77,5%, foi prevalente em relação ao masculino com 27 casos e 22,5%. A idade variou de 52 a 95 anos, com a média de 80,06 anos e desvio padrão de 7,87 anos. A média de idade do gênero masculino foi de 76,19 anos e desvio padrão de 8,321. O gênero feminino obteve a média de 81,18 anos com desvio padrão de 7,407. O tempo cirúrgico médio foi de 39,35 minutos, variando de 25 a 65 minutos. O tempo médio de radioscopia foi 1min7s, variando de 0,6 a 2 minutos e 3s. A redução foi considerada adequada em 92 casos (76,6%), quando obteve-se o alinhamento do eixo de carga, como valgo em 20 casos (16,6%) e como varo em oito casos (6,6%). O somatório médio do TAD (Tip Apex Distance) na incidência Ântero-posterior (AP) foi de 1,19cm, variando de 0,2 a 2,8cm; e no Perfil (P), de 1,14cm, variando de 0,3 a 2,52cm. Dos pacientes, 112 (93,3%) voltaram a andar e a dor pós-operatória em uma escala de 0 a 10, teve a média de 4,44. Dos 120 pacientes, 11 foram classificados como Tronzo I (9,1%), 24 como Tronzo II (20%), 58 como Tronzo III (48,3%), sete Tronzo III variante (5,8%) e 20 Tronzo IV (16,7%). As fraturas instáveis ocorreram em 85 (70,8%) pacientes, os quais 74 (61,6%) tinham idade superior a 75 anos. Já as fraturas estáveis em 35 (29,1%) pacientes, os quais 17 (14,1%) possuíam idade superior a 75 anos. Em relação ao risco anestésico, oito (6,6%) foram classificados como ASA I, 33 (27,5%) ASA II, 74 (61,6%) ASA III e cinco ASA IV (4,16%). Houve um caso de infecção (0,83%). Ocorreram 13 óbitos (10,8%) dentro do primeiro ano de pós-operatório. Desses, um (0,83%) foi classificado como Asa II, cinco (4,16%) como Asa III e sete (5,83%) Asa IV. Dos 85 pacientes com fraturas instáveis, 36 (30%) apresentaram complicações, como perda de redução em 7(5,88%) e migração do pino deslizante em 29 (24,1%). No grupo das 35 fraturas estáveis, as complicações ocorreram em 4 casos (3,33 %), sendo que a perda de redução ocorreu em um caso (0,83%) e a migração em 3 casos (2,5%). No total, a migração ocorreu em 33 casos (27,6%), sendo que desses, todos evoluíram para consolidação. A perda de redução ocorreu em oito (6,7%) e a falta de união, em um caso (0,83%). CONCLUSÃO: Concluímos que a técnica minimamente invasiva, Sistema Minus, é uma técnica segura, que permite a realização da cirurgia com baixa incidência de complicações, quando comparada aos demais métodos existentes / Abstract: INTRODUCTION: The surgical treatment of intertrochanteric fractures is still controversial, resulting in further studies. Many papers have appeared in reference to the advantages of minimal invasive procedures for these fractures. The aim of this study was to evaluate the complications of a minimal invasive procedure using a specific implant and instruments developed for the treatment of intertrochanteric fractures (Minus System). MATERIAL AND METHOD: One hundred and seventy two patients with intertrochanteric fractures of the femur were studied, and submitted to treatment with the Minus System. Fifty two patients were excluded from the study as they did not fulfil all criteria for inclusion. The initial protocol registered gender, age, operative details such as length of operation, length of fluoroscopy use, quality of reduction and fixation of the fracture. The clinical parameters considered included deambulatory ability, pain, Tronzo fracture classification and anesthesia risk according to ASA classification. Complications were divided into two groups: general complications (infection and mortality rate) and specific complications (implant migration, loss of reduction and non-union). Although the migration of a sliding nail has not been considered in the literature as a DHS complication (Hrubna e Skotak, 2010)1 RESULTS: There were 93 feminine cases (77.5%) prevailing on 27 masculine cases (22.5%). Age span was 52 to 95 years, with an average of 80.06 years (standard deviation of 7.87 years). The average age for men was 76.19 years with a standard deviation of 8.321. The average age for women was 81.18 years with a standard deviation of 7.407. The average operative length of time was 39.35 minutes (25 to 65 minutes). The average time of fluoroscopy was 1min 7sec (0.6 to 2min 3sec). Fracture reduction was considered adequate in 92 cases (76.6%), , in the present study it was taken into account. It is important to mention that migration here is the lateral impaction of the fracture without loss of reduction. when alignment with weight-bearing axis was obtained, valgus in 20 cases (16.6%) and varus in eight cases (6.6%). The average Tip Apex Distance (TAD) on an anteroposterior view was 1.19cm (variation of 0.2 to 2.52 cm) and lateral view was 1.14cm (variaton of 0.3 to 2.52cm). One hundred and twelve patients (93,3%) were able to walk with postoperative pain (average of 4.4 on a pain scale of 0 to 10). The classification of the 120 patients is as follows: 11 patients with Tronzo I (9,1%), 24 cases of Tronzo II (20%), 58 Tronzo III (48.3%), seven Tronzo III variant (5.8%) and 20 Tronzo IV (16.7%). Unstable fractures occured in 85 (70.8%) patients, and 74 (61.6%) were over 75 years of age. There were 35 stable fractures (29.1%), with 17 patients (14.1%) over 75 years of age. As to the anesthesia risk eight (6.6%) were classified as ASA I, 33 (27.5%) ASA II, 74 (61.6%) ASA III and five patients as ASA IV (4.16%). There was one case of infection (0.83%). During the first postoperative year there were 13 deaths (10.8%). Of these, one patient (0.83%) had been classified as ASA II, five (4.16%) as ASA III and seven (5.83%) as ASA IV. There were 36 patients (30%) with complications out of 85 patients with unstable fractures, with loss of reduction in seven (5.88%) and migration of the sliding nail in 29 (24.1%). In the group of 35 stable fractures there were complications in four cases (3.3 %), with loss of reduction in one case (0.83%) and migration in three (2.5%). The total number of migrations was 33 (27.5%), but resulted in union in all patients. The loss in reduction occurred in eight patients (6.7%) and non-union in one case (0.83%). CONCLUSION: The minimal invasive procedure, the Minus System, is a safe procedure, that provides adequate surgery with a low incidence of complications, when compared to other existing techniques / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências
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Binding sites in protein structures: characterisation and relation with destabilising regionsDessailly, Benoît 20 September 2007 (has links)
An increasing number of proteins with unknown function have their three-dimensional structure solved at high resolution. This situation, largely due to structural genomics initiatives, has been stimulating the development of automated structure-based function prediction methods. Knowledge of residues important for function – and more particularly – for binding can help automated prediction of function in different ways. The properties of a binding site such as its shape or amino acid composition can provide clues on the ligand that may bind to it. Also, having information on functionally important regions in similar proteins can refine the process of annotation transfer between homologues.<p>Experimental results indicate that functional residues often have an unfavourable contribution to the stability of the folded state of a protein. This observation is the underlying principle of several computational methods for predicting the location of functional sites in protein structures. These methods search protein structures for destabilising residues, with the assumption that these are likely to be important for function.<p>We have developed a method to detect clusters of destabilising residues which are in close spatial proximity within a protein structure. Individual residue contributions to protein stability are evaluated using detailed atomic models and an energy function based on fundamental physico-chemical principles.<p>Our overall aim in this work was to evaluate the overlap between these clusters of destabilising residues and known binding sites in proteins.<p>Unfortunately, reliable benchmark datasets of known binding sites in proteins are sorely lacking. Therefore, we have undertaken a comprehensive approach to define binding sites unambiguously from structural data. We have rigorously identified seven issues which should be considered when constructing datasets of binding sites to validate prediction methods, and we present the construction of two new datasets in which these problems are handled. In this regard, our work constitute a major improvement over previous studies in the field.<p>Our first dataset consists of 70 proteins with binding sites for diverse types of ligands (e.g. nucleic acids, metal ions) and was constructed using all available data, including literature curation. The second dataset contains 192 proteins with binding sites for small ligands and polysaccharides, does not require literature curation, and can therefore be automatically updated.<p>We have used our dataset of 70 proteins to evaluate the overlap between destabilising regions and binding sites (the second dataset of 192 proteins was not used for that evaluation as it constitutes a later improvement). The overlap is on average limited but significantly larger than random. The extent of the overlap varies with the type of bound ligand. Significant overlap is obtained for most polysaccharide- and small ligand-binding sites, whereas no overlap is observed for nucleic acid-binding sites. These differences are rationalised in terms of the geometry and energetics of the binding sites.<p>Although destabilising regions, as detected in this work, can in general not be used to predict all types of binding sites in protein structures, they can provide useful information, particularly on the location of binding sites for polysaccharides and small ligands.<p>In addition, our datasets of binding sites in proteins should help other researchers to derive and validate new function prediction methods. We also hope that the criteria which we use to define binding sites may be useful in setting future standards in other analyses. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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Essays on the theory of organizations and network industriesDessein, Wouter H. January 2000 (has links)
Doctorat en sciences sociales, politiques et économiques / info:eu-repo/semantics/nonPublished
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Les expressions figées en français et en BCMS : traduction, comparaison / Idioms in French and in BCMS : translation, comparisonLjepavic, Danijela 22 June 2015 (has links)
Cette thèse procède à une comparaison des expressions figées entre les langues BCMS (bosniaque/bosnien, croate, monténégrin, serbe) et le français en vue de la traduction. Dans la première partie, l'étude commence par la définition des expressions figées et des critères de figement. Après avoir fait le point sur la question des langues BCMS, on présente le corpus des expressions figées en BCMS et en français, avec leur répartition dans différents domaines culturels et la distinction de trois types d'expressions : calques, expressions transparentes, expressions opaques. La seconde partie est consacrée à l'analyse comparative des expressions figées en BCMS et en français. Elle commence par un parcours de leurs différentes origines, puis on examine les fondements culturels des expressions figées, en fonction de différents domaines fournisseurs. On développe ensuite une analyse linguistique comparée des expressions figées, en détaillant les noms composés et les différentes locutions (verbales, adjectivales etc.) et en intégrant la dimension rhétorique, notamment les métaphores. Pour finir, après une mise au point générale sur la traduction, on examine les problèmes d'interprétation et les différentes solutions de traduction des expressions figées dans les deux sens, entre français et BCMS. / This thesis makes a comparison between the idioms of the BCMS languages (Bosnian, Croatian, Montenegrin, Serbian) on the one side, and the French language on the other, in the domain of translation.In the first segment, the study begins with the definition of idioms and the criteria for fixation. After the explanation of differences among BCMS languages, we present the corpus of idioms in BCMS and in French, with their distribution within different cultural domains, while distinguishing among three types of idiomatic expressions: literal, transparent, and opaque.The second part is devoted to the comparative analysis of idioms in BCMS and French. It begins with a record of their different origins, after which we examine the cultural foundations of expressions, depending on different domains. We develop a comparative linguistic analysis of idioms, giving details on various compound names and phrases (verbal, adjectival, etc.), and integrating the rhetorical dimension, including metaphors. Finally, after an overall focus on translating, we examine issues found in interpretation and translation solutions for different idioms between French and BCMS.
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Olše lepkavá (Alnus glutinosa L. Gaertn.) v symbióze s bakteriemi rodu Frankia a jejich růst na půdách výsypek po těžbě uhlí / European black alder (Alnus glutinosa L. Gaertn.) in symbiosis with Frankia and their growth on post-mining heap soilsBuchbauerová, Lucie January 2017 (has links)
Alder (Alnus glutinosa L. Gaertn.) is a species of a pioneer plant usually colonizing sites in the early stage of ecological succession, such as spoil heaps after open-cast brown coal mining in the Sokolov mining district in north western Bohemia, Czech Republic. These spoil heaps are very poor in nutrients available for plants, yet alders grow in a mutualistic relationship with actinomycetes Frankia, which live in root nodules of the alder plants. Frankia are able of fixing atmospheric nitrogen (N2) to ammonia (NH3) molecules, which can be then assimilate by alders, via enzyme nitrogenase. Thus, in the early stages of succession, alders have a competitive advantage to other non- fixing plant species living only on nitrates (NO3 - ) and ammonia ions (NH4 + ) present in soils. The aim of this study was to conduct and assess two greenhouse experiments. The first experiment studied the response of alder growth to presence of Frankia and arbuscular mycorrhizal fungi of order Glomerales. The performance of alder growth was significantly higher when alders were inoculated with both Frankia and mycorrhizal fungi in comparison to when alders have grown on their own or only with a mycorrhizal symbiont - both on 14 and 60 years old soils from Sokolov mines. In the second experiment, soil pH and iron (Fe) and...
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Aspects of confinement in Yang-Mills theories / Aspects du confinement dans les théories de Yang-MillsTresmontant, Andréas 27 September 2016 (has links)
On étudie les théories de Yang-Mills. Pour ce faire, nous appliquons une nouvelle procédure de fixation de jauge qui vise à prendre en compte la présence des copies de Gribov. Ces copies correspondent à des solutions supplémentaires de la condition de jauge et ne sont pas prises en compte dans la procédure standard de Faddeev-Popov. Cette nouvelle procédure de fixation de jauge a d'abord été implémenté dans la jauge de Landau, où le régime de basse énergie a pu être étudié simplement par la théorie de perturbation et les propagateurs des gluons et des ghosts ont été trouvé en bon accord avec les résultats du réseau. Dans une première partie, nous appliquons cette procédure à une classe de jauges covariantes et non-linéaires (les jauges de Curci-Ferrari-Delbourgo-Jarvis). Nous montrons que ces jauges sont renormalisables en dimension quatre et donnons explicitement les expressions des constantes de renormalisation à une boucle. Nous calculons en théorie de perturbation les propagateurs de la théorie à l'ordre d'une boucle et implémentons le groupe de renormalisation. La seconde partie concerne l'étude du cas à température finie et de la transition de phase confinement-déconfinement. Nous travaillons dans une extention massive de la jauge de Landau-DeWitt. Nous calculons les propagateurs à une boucle et montrons qu'ils présentent de clairs signaux de la transition de phase à la différence de la jauge de Landau. / We investigate Yang-Mills theories. In particular, we follow a recently proposed new gauge-fixing procedure that aims at dealing with the presence of the so-called Gribov copies. These copies correspond to additional solutions to the gauge equation that are disregarded in the standard Faddeev-Popov procedure. This novel gauge-fixing approach was first implemented in the Landau gauge, where the low momentum regime was investigable by means of simple perturbation theory and the one-loop gluon and ghost propagators were found in good agreement with lattice results. In a first part, we extend this proposal to a class of nonlinear covariant (the Curci-Ferrari-Delbourgo-Jarvis) gauges . We prove that these gauges are renormalizable in four dimensions. We provide explicit expression of the renormalization constants at one-loop order. Then we compute the various propagators of the theory at one-loop order with and without renormalization group improvement. The second part of the thesis concerns the finite temperature case and in particular the study of the confinement-deconfinement phase transition. We work in the Landau-DeWitt gauge (a background extention of the Landau gauge) which allows for an explicit presence of an order parameter of the phase transition. This gauge is implemented following the previous gauge-fixing procedure. In particular it has been shown that the phase transition can be studied in perturbation theory. Here, we compute at one-loop order the gluon and ghost propagators (for SU(2) gauge group) and show that they display strong signals of the phase transition. This is to be put in regards with the results obtained for the Landau gauge propagators.
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Proteômica da interação planta-patógeno/simbionte em cana-de-açúcar (Saccharum spp.)ALMEIDA, Renata Rodrigues de 30 July 2015 (has links)
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Previous issue date: 2015-07-30 / CAPES / Reuni / CNPq / A cana-de-açúcar tem papel relevante na economia brasileira, apesar de estar sucetível a fatores bióticos e abióticos que influenciam para redução de produtividade agrícola e industrial. Apesar de existirem organismos como agentes causais de doenças que contribuam com danos à cana-de-açúcar, micro-organismos simbiontes interagem com a cultura conferindo benefícios no processo, tais como a fixação de Nitrogênio. Dessa forma, a análise das proteínas envolvidas na resposta a fatores bióticos pode auxiliar no desenvolvimento de novas variedades. No presente trabalho, foi analisado o proteoma da interação da cana-de-açúcar com patógeno (Leifsonia xyli subsp. xyli; Lxx) e/ou com o simbionte (Gluconacetobacter diazotrophicus; Gd) por 2-DE (Eletroforese bidimensional) seguida de MS (Espectrometria de massa). Os resultados da eletroforese bidimensional com a interação cana-de-açúcar/Gd mostraram que 173 spots foram diferencialmente expressos. A análise por espectrometria de massa identificou 65 proteínas. Tais proteínas foram principalmente associadas com produção de energia, componentes de fotossistemas e indução de resposta a estímulos ambientais. Na interação cana-de-açúcar/Lxx, em análise da eletroforese bidimensional, se observou 138 spots com expressão diferenciada. A análise por espectrometria de massa identificou 56 proteínas responsivas a estresses bióticos, defesa e metabolismo de carboidratos. Durante a interação simultânea com Gd e Lxx, o proteoma da cana-de-açúcar a análise da eletroforese bidimensional mostrou que 142 spots apresentaram nível de expressão alterada. A análise por espectrometria de massa identificou 30 proteínas associadas com metabolismo de carboidratos e defesa contra estresses bióticos. Os resultados obtidos compõem um conjunto de proteínas (e genes codificantes) com provável utilidade como marcadores funcionais auxiliares no melhoramento genético, na seleção de variedades com interação benéfica de crescimento/fixação biológica de nitrogênio com Gd, e/ou maior resistência à patogenicidade de Lxx. / The sugarcane has an important role in the Brazilian economy, despite its suceptibility to biotic and abiotic factors that decrease agricultural and industrial productivity. Although there are parasitic organisms that contribute to damage sugarcane, symbiotic microorganisms interact with the culture, providing benefits in the process, such as nitrogen fixation. Thus, the analysis of proteins involved in the response to biotic factors may assist the developing new sugarcane varieties. In this study, we analyzed the proteome of the interaction of sugarcane with pathogen (Leifsonia xyli subsp. xyli; Lxx) and / or symbiont (Gluconacetobacter diazotrophicus; Gd) by 2-DE (Two-dimensional electrophoresis) followed by MS (Mass Spectrometry). The results of two-dimensional electrophoresis with sugarcane / Gd interaction showed that 173 spots showed altered expression level. Analysis by mass spectrometry identified 65 proteins. These differentially expressed proteins were primarily associated with energy production, and induction components photosystems response to environmental stimuli. Since the sugarcane interaction / Lxx the analysis of two-dimensional electrophoresis demonstrated that 138 spots showed altered expression level. The analysis by mass spectrometry identified 56 proteins responsive to biotic stresses, defense and carbohydrate metabolism. During simultaneous interaction with Gd and Lxx, the proteome analysis of sugarcane showed that 142 spots with altered expression level. Analysis by mass spectrometry identified 30 proteins associated with carbohydrate metabolism and protection against biotic stresses. The results obtained in this work comprise a set proteins (and encoding genes) with probable utility as auxiliary functional markers in plant breeding, in the selection of varieties with beneficial interaction for growth/biological nitrogen fixation with Gd, and/or increased resistance to pathogenic Lxx.
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Reserva nitrogenada no genero Beijerinckia isolada da rizosfera de cana-de-açúcar. / Nitrogen reserve in the genus Beijerinckia isolated from sugarcane rhizosphere.Tania Regina dos Santos 30 August 2011 (has links)
Beijerinckia sp., bactéria de vida livre fixadora de nitrogênio, comumente encontrada em solos tropicais lateríticos. A cianoficina produzida por cianobactérias é a única reserva nitrogenada intracelular descrita até hoje. O presente trabalho teve como principal objetivo verificar o acúmulo de material nitrogenado intracelular associado à Fixação Biológica de Nitrogênio em cinco isolados de Beijerinckia da rizosfera de cana-de-açúcar (Saccharum sp.). Os resultados mostraram um aumento na concentração de proteína celular total concomitantemente a atividade da nitrogenase durante a fase estacionária de todos os isolados. A fixação de nitrogênio durante esta fase sugere que o destino do nitrogênio fixado seriam os grânulos de armazenamento. A análise química desta reserva confirmou a presença de arginina em teor muito elevado em relação aos demais aminoácidos sugerindo uma reserva nitrogenada diferente da cianoficina. Em recombinantes de Escherichia coli confirmou-se um possível gene envolvido no armazenamento de material nitrogenado em Beijerinckia sp. / Beijerinckia sp. bacteria free-living nitrogen-fixing, commonly found in tropical lateritic soils. The cyanophycin produced by cyanobacteria is the only intracellular nitrogen reserve described to date. This study aimed to verify the intracellular buildup of nitrogen associated with Biological Nitrogen Fixation in five Beijerinckia isolated from the rhizosphere of sugarcane (Saccharum sp.). The results showed an increase in total cellular protein concentration concomitantly nitrogenase activity during the stationary phase of all isolates. The nitrogen fixation during this phase suggests that the fate of fixed nitrogen would be the storage granules. Chemical analysis of the reserve confirmed the presence of very high content of arginine in relation to other amino acids suggesting a different reserve of cyanophycin. In recombinant Escherichia coli confirmed a possible gene involved in nitrogen storage material in Beijerinckia sp.
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