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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

O realismo do romance contemporâneo de Bernardo de Carvalho: uma narrativa labiríntica em abismo

Lemos, Sandra Maria Fontinha de 29 April 2014 (has links)
Made available in DSpace on 2016-04-28T19:58:52Z (GMT). No. of bitstreams: 1 Sandra Maria Fontinha de Lemos.pdf: 666400 bytes, checksum: bb556759d39af6bc2c85747eaa036b1e (MD5) Previous issue date: 2014-04-29 / This academic research clings to the analysis of the novel O Sol Se Põe Em São Paulo, by Bernardo Carvalho as a representative sample of the Brazilian contemporary novel. In this paper we intend to show the features that define the different phases of the genre and the features which are still being used in the contemporary novel. For that we tried to understand the architectural-narrative of the corpus s text, decode what kind of conundrum the novel deals with and what kind of issues have the characters faced. All these issues are previously established as a basis to a hypothesis namely, the echogenic analysis of the text. We studied the process of the text production taking into consideration the wiles used by Bernardo Carvalho and that he took as stratagem to echo reflection, as an art craft amplifier. We acknowledge that these art crafts work as a mirrored system repeating the same function. Another subject analyzed in this paper is the role and the function of the voices, its interaction. We tried to pinpoint the fact that all the wiles used by the author follow the same stratagem, the same objective and that although these wiles had being used before, separately, they represent the idea that contemporary literature speaks of: that is an egotic literature. To sustain the critical-theorical foundation upon which this thesis is structured we chose some authors: Mikhail Bakhtin, Clement Rosset, Otto Rank, Lucien Dallenbach, Tzvetan Todorov, Michel de Certeau, and Merleau Ponty, among others. Along these three chapters we developed a cohesive text in which we could put up with the proposed theories and themes in accordance with the Bernardo Carvalho`s novel we analized. It stood out how the duplication, the mise en abyme and the exotopy reverberate, by the voice and the word, throughout the text drawing a realistic image in this contemporary novel / Esta pesquisa atém-se ao estudo do romance O Sol se põe em São Paulo, de Bernardo Carvalho, como um representante do romance brasileiro contemporâneo. Pretende-se mostrar os traços que marcaram as diferentes etapas do desenvolvimento do gênero e que ainda se mantêm no romance contemporâneo. Para tanto buscou-se entender a arquinarrativa da escritura do corpus analisado e decifrar de que tipo de enigma se trata e que problemática enfrentam suas personagens. Todas estas questões se colocam previamente como fundamento para a hipótese do trabalho que é a análise ecogênica da escritura do texto. A pesquisa do processo de produção da escritura leva em conta os artifícios usados por Bernardo Carvalho, que tomamos como artifício de propagação de eco, como artifícios amplificadores. Artifícios esses que entendemos funcionar como um sistema espelhado repetindo a mesma função. Outro assunto abordado nesta pesquisa é o papel e a posição das vozes, sua interação. Ressaltamos o fato de que os artifícios usados pelo autor seguem todos a mesma diretriz, o mesmo objetivo e que embora já tenham sido usados em separado, anteriormente, eles representam a literatura egótica contemporânea. Para dar suporte conceitual ao núcleo teórico-crítico deste estudo fundamentamo-nos em: Mikhail Bakhtin, Clement Rosset, Otto Rank, Lucien Dallenbach, Tzvetan Todorov, Michel de Certeau e Merleau Ponty, dentre outros. No desenvolvimento dos três capítulos colocamos as teorias e os temas propostos em diálogo com o romance de Bernardo Carvalho que analisamos, e demonstramos como a duplicação, a exotopia e o mise en abyme (artifícios ecogênicos) se propagam pela voz e pela palavra por toda escritura, desenhando uma imagem realista neste romance contemporâneo
172

Using On-Chip Error Detection to Estimate FPGA Design Sensitivity to Configuration Upsets

Keller, Andrew Mark 01 April 2017 (has links)
SRAM-based FPGAs provide valuable computation resources and reconfigurability; however, ionizing radiation can cause designs operating on these devices to fail. The sensitivity of an FPGA design to configuration upsets, or its SEU sensitivity, is an indication of a design's failure rate. SEU mitigation techniques can reduce the SEU sensitivity of FPGA designs in harsh radiation environments. The reliability benefits of these techniques must be determined before they can be used in mission-critical applications and can be determined by comparing the SEU sensitivity of an FPGA design with and without these techniques applied to it. Many approaches can be taken to evaluate the SEU sensitivity of an FPGA design. This work describes a low-cost easier-to-implement approach for evaluating the SEU sensitivity of an FPGA design. This approach uses additional logic resources on the same FPGA as the design under test to determine when the design has failed, or deviated from its specified behavior. Three SEU mitigation techniques were evaluated using this approach: triple modular redundancy (TMR), configuration scrubbing, and user-memory scrubbing. Significant reduction in SEU sensitivity is demonstrated through fault injection and radiation testing. Two LEON3 processors operating in lockstep are compared against each other using on-chip error detection logic on the same FPGA. The design SEU sensitivity is reduced by 27x when TMR and configuration scrubbing are applied, and by approximately 50x when TMR, configuration scrubbing, and user-memory scrubbing are applied together. Using this approach, an SEU sensitivity comparison is made of designs implemented on both an Altera Stratix V FPGA and a Xilinx Kintex 7 FPGA. Several instances of a finite state machine are compared against each other and a set of golden output vectors, all on the same FPGA. Instances of an AES cryptography core are chained together and the output of two chains are compared using on-chip error detection. Fault injection and neutron radiation testing reveal several similarities between the two FPGA architectures. SEU mitigation techniques reduce the SEU sensitivity of the two designs between 4x and 728x. Protecting on-chip functional error detection logic with TMR and duplication with compare (DWC) is compared. Fault injection results suggest that it is more favorable to protect on-chip functional error detection logic with DWC than it is to protect it with TMR for error detection.
173

Étude de faisabilité d'un micro-contrôleur de très haute sécurité

Chaumontet, Gilles 26 October 1990 (has links) (PDF)
Actuellement, toutes les applications critiques mettant en jeu la vie humaine ne peuvent pas être assurées par des systèmes complexes utilisant des circuits intégrés répliques; il est nécessaire d'utiliser des composants discrets de sécurité intrinsèque, d'un encombrement et d'un cout prohibitifs. Pour relever ce défi, le micro-contrôleur maps qui doit gérer la signalisation ferroviaire, bénéficie de l'intégration d'un circuit logique autotestable, en-ligne (duplication duale+parité) et hors-ligne, suivant le principe de la technique ubist. Le maps dispose aussi d'une interface de sortie apte a produire des signaux de commande en fréquence, soit surs soit corrects. Il dispose également d'une interface d'entrée capable de n'accepter des signaux externes qu'après les avoir rendus surs ou corrects. Ces deux interfaces intégrées pour la première fois, sur la même puce que le circuit autotestable, sont strongly fail-safe. Seules les communications avec l'extérieur se font par échange de messages fortement codes sans qu'aucun matériel ne soit rajoute. En conséquence, l'étude que l'on présente permet d'apporter une nouvelle démarche de conception des systèmes hautement critiques, tout en assurant un degré de sécurité nettement plus élevé (détection de toutes pannes triples) que celui donne par les systèmes actuels, et ceci pour un volume et un cout plus faibles
174

The Action of natural selection in recently duplicated genes

Lorente Galdós, Maria Belén 11 November 2011 (has links)
Identification of signatures of positive selection has long been a major issue for understanding the unique features of any given species. However, only a fraction of human genes have been interrogated. Genes within segmental duplications are usually omitted due to the limitations of draft genome assemblies and the methodological reliance on accurate gene trees. In this work, we show the feasibility of a new method that does not need accurate gene trees or individual high-quality assemblies. We applied the concept to study exon evolution in the human genome, identifying 74 exons with evidence for rapid coding sequence evolution during human and Old World monkey evolution. Our results suggest abundant accelerated coding sequence evolution within duplicated regions of the genome and provide a more comprehensive view of the role of selection on the human genome. / La identificación de señales debidas a la acción de la selección positiva es de gran relevancia para desvelar características únicas de las especies. A pesar de ello, solo una fracción de genes humanos han sido analizados. Los genes incluidos en duplicaciones segmentarias son normalmente ignorados debido a limitaciones impuestas por la naturaleza preliminar de los genomas distintos al humano, así como por la dependencia en adecuados árboles filogenéticos. En este proyecto, demostramos la viabilidad de un nuevo método que no necesita árboles filogenéticos correctos ni ensamblajes de genomas de alta calidad. Hemos aplicado el concepto al genoma humano y hemos identificado 74 exones que muestran evidencia de haber evolucionado más rápidamente desde la separación de los humanos y los monos del viejo mundo. Nuestros resultados sugieren que ha habido abundante evolución acelerada dentro de las regiones duplicadas y ofrece una visión más esclarecedora del rol de la selección en la evolución del genoma humano.
175

O narrador e seus duplos em Nenhum olhar e em Cemitério de pianos, de José Luís Peixoto / The narrator and his double in Nenhum olhar and Cemitério de pianos, by José Luís Peixoto

Kátia Cristina Franco de Medeiros Suelotto 24 September 2012 (has links)
O principal objetivo desta tese é a investigação do foco narrativo nos romances Nenhum olhar e Cemitério de pianos, de José Luís Peixoto, com vistas a defender a hipótese de que o narrador em primeira pessoa promove a assunção de duplos. Ambas as obras trazem personagens que contam a sua história e, no processo da narração, entram em contato consigo mesmas, sob uma perspectiva pautada nas deformações intrínsecas à passagem do tempo. Nesse sentido, a faculdade da memória assume um papel fundamental na relativização do passado. Trata-se, em primeiro lugar, de uma análise do plano da expressão. Concomitante à questão do narrador e seus duplos, observamos que o conteúdo de ambos os romances evoca o tema da busca da salvação. Compreendemos que a concepção de mundo que permeia as referidas obras está pautada na jornada de Cristo na Terra e, em especial, ao drama da Paixão. Concluímos, pois, que, ao desejo do narrador em primeira pessoa de contar a sua história, estão intimamente relacionados o fenômeno do duplo e a negação da morte. Desse modo, por meio da duplicação, as personagens entram em contato com uma realidade supratemporal, fundada no mito. / The main objective of this thesis is the investigation of narrative focus on novels Nenhum olhar and Cemitério de pianos, by José Luís Peixoto, in order to defend the hypothesis that the first-person narrator promotes the assumption of doubles. Both works bring characters to tell their story and in the process of narration, get in touch with themselves, a perspective based on the deformations intrinsic to the passage of time. In this sense, the faculty of memory plays a key role in the relativization of the past. It is, firstly, an analysis of the level of expression. Concomitant with the question of the narrator and his double, we observed that the contents of both novels evoke the theme of the quest for salvation. We understand that the world view that permeates these works is based on the journey of Christ on Earth and in particular the drama of the Passion. Therefore we conclude that the desire of the first-person narrator to tell his story, are closely related to the phenomenon of the double and the denial of death. Thus, by duplicating the characters come into contact with supratemporal reality, founded on myth.
176

A combinatorial study of soundness and normalization in n-graphs

ANDRADE, Laís Sousa de 29 July 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-04-24T14:03:12Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertacao-mestrado.pdf: 2772669 bytes, checksum: 25b575026c012270168ca5a4c397d063 (MD5) / Made available in DSpace on 2017-04-24T14:03:12Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertacao-mestrado.pdf: 2772669 bytes, checksum: 25b575026c012270168ca5a4c397d063 (MD5) Previous issue date: 2015-07-29 / CNPQ / N-Graphs is a multiple conclusion natural deduction with proofs as directed graphs, motivated by the idea of proofs as geometric objects and aimed towards the study of the geometry of Natural Deduction systems. Following that line of research, this work revisits the system under a purely combinatorial perspective, determining geometrical conditions on the graphs of proofs to explain its soundness criterion and proof growth during normalization. Applying recent developments in the fields of proof graphs, proof-nets and N-Graphs itself, we propose a linear time algorithm for proof verification of the full system, a result that can be related to proof-nets solutions from Murawski (2000) and Guerrini (2011), and a normalization procedure based on the notion of sub-N-Graphs, introduced by Carvalho, in 2014. We first present a new soundness criterion for meta-edges, along with the extension of Carvalho’s sequentization proof for the full system. For this criterion we define an algorithm for proof verification that uses a DFS-like search to find invalid cycles in a proof-graph. Since the soundness criterion in proof graphs is analogous to the proof-nets procedure, the algorithm can also be extended to check proofs in the multiplicative linear logic without units (MLL−) with linear time complexity. The new normalization proposed here combines a modified version of Alves’ (2009) original beta and permutative reductions with an adaptation of Carbone’s duplication operation on sub-N-Graphs. The procedure is simpler than the original one and works as an extension of both the normalization defined by Prawitz and the combinatorial study developed by Carbone, i.e. normal proofs enjoy the separation and subformula properties and have a structure that can represent how patterns lying in normal proofs can be recovered from the graph of the original proof with cuts. / N-Grafos é uma dedução natural de múltiplas conclusões onde provas são representadas como grafos direcionados, motivado pela idéia de provas como objetos geométricos e com o objetivo de estudar a geometria de sistemas de Dedução Natural. Seguindo esta linha de pesquisa, este trabalho revisita o sistema sob uma perpectiva puramente combinatorial, determinando condições geométricas nos grafos de prova para explicar seu critério de corretude e crescimento da prova durante a normalização. Aplicando desenvolvimentos recentes nos campos de grafos de prova, proof-nets e dos próprios N-Grafos, propomos um algoritmo linear para verificação de provas para o sistema completo, um resultado que pode ser comparado com soluções para roof-nets desenvolvidas por Murawski (2000) e Guerrini (2011), e um procedimento de normalização baseado na noção de sub-N-Grafos, introduzidas por Carvalho, em 2014. Apresentamos primeiramente um novo critério de corretude para meta-arestas, juntamente com a extensão para todo o sistema da prova da sequentização desenvolvida por Carvalho. Para este critério definimos um algoritmo para verificação de provas que utiliza uma busca parecida com a DFS (Busca em Profundidade) para encontrar ciclos inválidos em um grafo de prova. Como o critério de corretude para grafos de provas é análogo ao procedimento para proof-nets, o algoritmo pode também ser estendido para validar provas em Lógica Linear multiplicativa sem units (MLL−) com complexidade de tempo linear. A nova normalização proposta aqui combina uma versão modificada das reduções beta e permutativas originais de Alves com uma adaptação da operação de duplicação proposta por Carbone para ser aplicada a sub-N-Grafos. O procedimento é mais simples do que o original e funciona como uma extensão da normalização definida por Prawitz e do estudo combinatorial desenvolvido por Carbone, i.e. provas em forma normal desfrutam das propriedades da separação e subformula e possuem uma estrutura que pode representar como padrões existentes em provas na forma normal poderiam ser recuperados a partir do grafo da prova original com cortes.
177

Removing DUST using multiple alignment of sequences

Rodrigues, Kaio Wagner Lima, 92991221146 21 September 2016 (has links)
Submitted by Kaio Wagner Lima Rodrigues (kaiowagner@gmail.com) on 2018-08-23T05:45:00Z No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) kaio-tese.pdf: 3615178 bytes, checksum: dc547b203670c1159f46136e021a4825 (MD5) kaio-folha-de-aprovacao.jpg: 3343904 bytes, checksum: b00e5c4807f5a7e10eddc2eed2de5f12 (MD5) / Approved for entry into archive by Secretaria PPGI (secretariappgi@icomp.ufam.edu.br) on 2018-08-23T19:08:57Z (GMT) No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) kaio-tese.pdf: 3615178 bytes, checksum: dc547b203670c1159f46136e021a4825 (MD5) kaio-folha-de-aprovacao.jpg: 3343904 bytes, checksum: b00e5c4807f5a7e10eddc2eed2de5f12 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-08-24T13:43:58Z (GMT) No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) kaio-tese.pdf: 3615178 bytes, checksum: dc547b203670c1159f46136e021a4825 (MD5) kaio-folha-de-aprovacao.jpg: 3343904 bytes, checksum: b00e5c4807f5a7e10eddc2eed2de5f12 (MD5) / Made available in DSpace on 2018-08-24T13:43:58Z (GMT). No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) kaio-tese.pdf: 3615178 bytes, checksum: dc547b203670c1159f46136e021a4825 (MD5) kaio-folha-de-aprovacao.jpg: 3343904 bytes, checksum: b00e5c4807f5a7e10eddc2eed2de5f12 (MD5) Previous issue date: 2016-09-21 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / A large number of URLs collected by web crawlers correspond to pages with duplicate or near-duplicate contents. These duplicate URLs, generically known as DUST (Different URLs with Similar Text), adversely impact search engines since crawling, storing and using such data imply waste of resources, the building of low quality rankings and poor user experiences. To deal with this problem, several studies have been proposed to detect and remove duplicate documents without fetching their contents. To accomplish this, the proposed methods learn normalization rules to transform all duplicate URLs into the same canonical form. This information can be used by crawlers to avoid fetching DUST. A challenging aspect of this strategy is to efficiently derive the minimum set of rules that achieve larger reductions with the smallest false positive rate. As most methods are based on pairwise analysis, the quality of the rules is affected by the criterion used to select the examples and the availability of representative examples in the training sets. To avoid processing large numbers of URLs, they employ techniques such as random sampling or by looking for DUST only within sites, preventing the generation of rules involving multiple DNS names. As a consequence of these issues, current methods are very susceptible to noise and, in many cases, derive rules that are very specific. In this thesis, we present a new approach to derive quality rules that take advantage of a multi-sequence alignment strategy. We demonstrate that a full multi-sequence alignment of URLs with duplicated content, before the generation of the rules, can lead to the deployment of very effective rules. Experimental results demonstrate that our approach achieved larger reductions in the number of duplicate URLs than our best baseline in two different web collections, in spite of being much faster. We also present a distributed version of our method, using the MapReduce framework, and demonstrate its scalability by evaluating it using a set of 7.37 million URLs. / Um grande número de URLs obtidas por coletores corresponde a páginas com conteúdo duplicado ou quase duplicado, conhecidas em Inglês pelo acrônimo DUST, que pode ser traduzido como Diferentes URLs com Texto Similar. DUST são prejudiciais para sistemas de busca porque ao serem coletadas, armazenadas e utilizadas, contribuem para o desperdício de recursos, a criação de rankings de baixa qualidade e, consequentemente, uma experiência pior para o usuário. Para lidar com este problema, muita pesquisa tem sido realizada com intuito de detectar e remover DUST antes mesmo de coletar as URLs. Para isso, esses métodos se baseiam no aprendizado de regras de normalização que transformam todas as URLs com conteúdo duplicado para uma mesma forma canônica. Tais regras podem ser então usadas por coletores com o intuito de reconhecer e ignorar DUST. Para isto, é necessário derivar, de forma eficiente, um conjunto mínimo de regras que alcance uma grande taxa de redução com baixa incidência de falsos-positivos. Como a maioria dos métodos propostos na literatura é baseada na análise de pares, a qualidade das regras é afetada pelo critério usado para selecionar os exemplos de pares e a disponibilidade de exemplos representativos no treino. Para evitar processar um número muito alto de exemplos, em geral, são aplicadas técnicas de amostragem ou a busca por DUST é limitada apenas a sites, o que impede a geração de regras que envolvam diferentes nomes de DNS. Como consequência, métodos atuais são muito suscetíveis a ruído e, em muitos casos, derivam regras muito específicas. Nesta tese, é proposta uma nova técnica para derivar regras, baseada em uma estratégia de alinhamento múltiplo de sequências. Em particular, mostramos que um alinhamento prévio das URLs com conteúdo duplicado contribui para uma melhor generalização, o que resulta na geração de regras mais efetivas. Através de experimentos em duas diferentes coleções extraídas da Web, observa-se que a técnica proposta, além de ser mais rápida, filtra um número maior de URLs duplicadas. Uma versão distribuída do método, baseada na arquitetura MapReduce, proporciona a possibilidade de escalabilidade para coleções com dimensões compatíveis com a Web.
178

Avaliação genotípica de pacientes com polineuropatia inflamatória desmielinizante crônica: estudo da duplicação/deleção do gene PMP22 / Genotypic evaluation of patients with chronic inflammatory demyelinating polyneuropathy: study of the PMP22 gene duplication/delection.

Alex Eduardo da Silva 09 October 2014 (has links)
Introdução: Polineuropatias são doenças do sistema nervoso periférico com etiologias variadas. Dentre elas são freqüentes as inflamatórias e as hereditárias, com prevalência de 0,67-7,7/100000 e 7,9-82,3/100000 para polineuropatia inflamatória desmielinizante crônica (PIDC) e Doença de Charcot-Marie-Tooth (CMT), respectivamente. Existem poucas evidências de sobreposição entre estas duas doenças e também algumas dificuldades diagnósticas em situações específicas. Objetivos: Estudar a freqüência de mutações (duplicações e deleções) do gene PMP22 em uma coorte de pacientes inicialmente diagnosticados como PIDC ou suspeitos de apresentarem as duas condições, os sinais e sintomas sugestivos da sobreposição e os fatores implicados em erro de classificação da neuropatia. Métodos: 111 pacientes com diagnóstico de PIDC foram estudados. DNA foi isolado a partir de leucócitos de sangue periférico segundo protocolo padrão. Duplicações e deleções do gene PMP22 foram avaliadas através de marcadores polimórficos do DNA localizados dentro do cromossomo 17p11.2-12, o qual contém o gene PMP22. Achados clínicos e laboratoriais também foram estudados e comparados entre os grupos. Resultados: Dentre os 111 pacientes estudados, mutações no PMP22 foram encontradas em 10 (9%), sendo duplicações em 9 pacientes e deleção em 1 paciente. Concomitância entre PIDC e CMT foi verificada em 4 pacientes (3,6%), todos com duplicação do PMP22. Os outros 6 pacientes foram diagnosticados como CMT puro (5) ou Neuropatia Hereditária Susceptível à Compressão (1), visto que não apresentaram melhora com o uso de tratamento imunomodulador e/ou imunossupressor (5 casos) ou foi estabelecido diagnóstico alternativo associado (1). Os outros 101 pacientes não tiveram duplicação nem deleção deste gene e, portanto, tinham PIDC apenas. Idade média dos pacientes com PIDC/CMT foi de 23,8±18,0 anos e 43,6±19,3 anos para pacientes sem mutações (p=0,04). Houve diferença estatísticamente significativa na resposta ao tratamento entre os grupos PIDC/CMT X CMT (p=0,008) e PIDC X CMT (p=0,00). Ausência de história familiar e presença de doenças e hábitos ligados ao desenvolvimento de neuropatias periféricas, como diabetes mellitus e ingesta de bebidas alcoólicas, por exemplo, bem como achados atípicos na eletroneuromiografia e na biópsia de nervo podem ter contribuído para a confusão diagnóstica nos casos de CMT puro. Conclusões: Alguns pacientes podem desenvolver PIDC em associação com CMT e se beneficiam do tratamento. A neuropatia hereditária poderia predispor à neuropatia inflamatória, uma vez que estes pacientes tendem a apresentar essa condição em idades mais precoces. Cautela deve ser dispensada àqueles pacientes com suspeita diagnóstica de PIDC que não têm os achados clássicos ou não melhoram com o tratamento, uma vez que podem apresentar outras etiologias para a neuropatia, dentre elas uma neuropatia hereditária, como a CMT. / Introduction: Polyneuropathies are peripheral nervous system disorders with a wide range of etiologies. Among them, inflammatory and hereditary are frequent with prevalence of 0.67-7.7/100000 and 7.9-82.3/100000, for chronic inflammatory demyelinating polyneuropathy (CIDP) and Charcot-Marie-Tooth disease (CMT), respectively. There are a few evidence of ovelapping between these two conditions and also some diagnostic difficulties in specific situations. Objectives: To study the frequency of mutations in PMP22 gene (duplications and delections) among a cohort of patients initially diagnosed as CIDP or suspected to have both conditions, the signs and symptoms related to this ovelapping and factors implicated in misdiagnose. Methods: 111 patients with an initially CIDP suspected diagnosis were studied. DNA was isolated from peripheral blood leucocytes following a standard salting-out protocol. Duplications and delections in the PMP22 gene were analysed by polymorphic DNA markers located within the chromosome 17p11.2-12, wich contains the PMP22 gene. Clinical and laboratory findings were also studied and compared within groups. Results: Among 111 patients studied, 10 (9%) were found to harbor mutations in PMP22 gene, specifically duplications in nine and delection in one. We therefore diagnosed CIDP plus CMT in four patients (3.6%), all of them with a duplicated PMP22 gene. The other six patients were diagnosed as pure CMT (5) or Hereditary Neuropathy with liability to Pressure Palsy (1), as they did not improved with the use of immunomodulatory and/or immunosupressive treatment (five cases) or were found to have alternative associated diagnosis (one patient). The other 101 patients did not show duplication nor delection in this gene, so they had CIDP. Mean age of patients with CIDP/CMT were 23.8±18.0 years and 43.6±19.3 years for patients without mutations (p=0.04). There were statistically significant difference in treatmet response between groups CIDP/CMT X CMT (p=0.008) and CIDP X CMT (p=0.00). The lack of family history and presence of other diseases and habits linked to the development of peripheral neuropathies, as diabetes mellitus and alcohol intake, for instance, as well as atypical findings in electrodiagnostic studies and nerve biopsy may have contributed to misdiagnose in the pure CMT cases. Conclusions: Some patients may develop CIDP in association with CMT and have benefit from treatment. The hereditary neuropathy may predispose to the inflammatory neuropathy as these patients tend to show this condition at younger ages. Caution should be dispensed to those patients with a suspected diagnose of CIDP who do not have the classical disease findings or do not improve with treatment, as they can have alternative etiologies for the neuropathy, among them a hereditary neuropathy as CMT disease.
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Etudes d'objets combinatoires : applications à la bio-informatique / Study of Combinatorial Objects : Applications to Bioinformatics

Vernay, Rémi 29 June 2011 (has links)
Cette thèse porte sur des classes d’objets combinatoires, qui modélisent des données en bio-informatique. Nous étudions notamment deux méthodes de mutation des gènes à l’intérieur du génome : la duplication et l’inversion. Nous étudions d’une part le problème de la duplication-miroir complète avec perte aléatoire en termes de permutations à motifs exclus. Nous démontrons que la classe de permutations obtenue avec cette méthode après p duplications à partir de l’identité est la classe de permutations qui évite les permutations alternées de longueur 2p + 1. Nous énumérons également le nombre de duplications nécessaires et suffisantes pour obtenir une permutation quelconque de longueur n à partir de l’identité. Nous proposons également deux algorithmes efficaces permettant de reconstituer deux chemins différents entre l’identité et une permutation déterminée. Nous donnons enfin des résultats connexes sur d’autres classes proches. La restriction de la relation d’ordre < induite par le code de Gray réfléchi à l’ensemble des compositions et des compositions bornées induit de nouveaux codes de Gray pour ces ensembles. La relation d’ordre < restreinte à l’ensemble des compositions bornées d’un intervalle fournit encore un code de Gray. L’ensemble des ncompositions bornées d’un intervalle généralise simultanément l’ensemble produit et l’ensemble des compositions d’un entier et donc la relation < définit de façon unifiée tous ces codes de Gray. Nous réexprimons les codes de Gray de Walsh et Knuth pour les compositions (bornées) d’un entier à l’aide d’une unique relation d’ordre. Alors, le code de Gray deWalsh pour des classes de compositions et de permutations devient une sous-liste de celui de Knuth, lequel est à son tour une sous-liste du code de Gray réfléchi. / This thesis considers classes of combinatorial objects that model data in bioinformatics. We have studied two methods of mutation of genes within the genome : duplication and inversion. At first,we study the problem of the whole mirror duplication-random lossmodel in terms of pattern avoiding permutations. We prove that the class of permutations obtained with this method after p duplications from the identity is the class of permutations avoiding alternating permutations of length 2p + 1.We also enumerate the number of duplications that are necessary and sufficient to obtain any permutation of length n from the identity. We also suggest two efficient algorithms to reconstruct two different paths between the identity and a specified permutation. Finally,we give related results on other classes nearby. The restriction of the order relation < induced by the reflected Gray code for the sets of compositions and bounded compositions gives new Gray codes for these sets. The order relation < restricted to the set of bounded compositions of an interval also yields a Gray code. The set of bounded n-compositions of an interval simultaneously generalizes product set and compositions of an integer, and so < puts under a single roof all theseGray codes.We re-expressWalsh’s and Knuth’sGray codes for (bounded) compositions of an integer in terms of a unique order relation, and so Walsh’s Gray code becomes a sublist of Knuth’s code, which in turn is a sublist of the Reflected Gray Code.
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The flâneur in contemporary society with special reference to the work of Francis Alÿs

McDowall, Estelle 08 December 2011 (has links)
The contemporary flâneur is confronted with a radically different world in comparison to the Parisian arcades of the nineteenth century during which the idea of the flâneur was conceptualised. The current urban milieu of the flâneur is dominated by consumerism, computer systems and surveillance, and the research posed here explores the flâneur within this environment. The flâneur was originally visualised on the streets and arcades of the city; however, cities do not only exist as buildings and streets and have become global entities that are constituted from the physical and the virtual. Throughout this study reference is primarily made to the work of Francis Alÿs to elucidate theoretical concepts. This study proposes that there is an absence of the teleological goal in the journey of the flâneur and as such, the flâneur wanders the streets without aim; however, in the process creates narratives and leaves traces of his journey. The ubiquity of surveillance in the contemporary metropolis complicates the flâneur's relationship with the latter. Consequently the impact of surveillance on the flâneur and the flâneur's daily wanderings are examined to ascertain its influence on the flâneur in a hyperreal society. In contemporary thinking, the traditional idea of the male flâneur requires reassessment and this research investigates the possibility of the female flâneur and women's presence in the public spaces of the city and the virtual realm of cyberspace. Furthermore, women are intricately linked to consumerism and their experience and position in the city are influenced by being seen as objects of the gaze. / Dissertation (MA)--University of Pretoria, 2011. / Visual Arts / unrestricted

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