4 resultados para Annotations sémantiques

em Universidade Federal do Rio Grande do Norte(UFRN)


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With the rapid growth of databases of various types (text, multimedia, etc..), There exist a need to propose methods for ordering, access and retrieve data in a simple and fast way. The images databases, in addition to these needs, require a representation of the images so that the semantic content characteristics are considered. Accordingly, several proposals such as the textual annotations based retrieval has been made. In the annotations approach, the recovery is based on the comparison between the textual description that a user can make of images and descriptions of the images stored in database. Among its drawbacks, it is noted that the textual description is very dependent on the observer, in addition to the computational effort required to describe all the images in database. Another approach is the content based image retrieval - CBIR, where each image is represented by low-level features such as: color, shape, texture, etc. In this sense, the results in the area of CBIR has been very promising. However, the representation of the images semantic by low-level features is an open problem. New algorithms for the extraction of features as well as new methods of indexing have been proposed in the literature. However, these algorithms become increasingly complex. So, doing an analysis, it is natural to ask whether there is a relationship between semantics and low-level features extracted in an image? and if there is a relationship, which descriptors better represent the semantic? which leads us to a new question: how to use descriptors to represent the content of the images?. The work presented in this thesis, proposes a method to analyze the relationship between low-level descriptors and semantics in an attempt to answer the questions before. Still, it was observed that there are three possibilities of indexing images: Using composed characteristic vectors, using parallel and independent index structures (for each descriptor or set of them) and using characteristic vectors sorted in sequential order. Thus, the first two forms have been widely studied and applied in literature, but there were no records of the third way has even been explored. So this thesis also proposes to index using a sequential structure of descriptors and also the order of these descriptors should be based on the relationship that exists between each descriptor and semantics of the users. Finally, the proposed index in this thesis revealed better than the traditional approachs and yet, was showed experimentally that the order in this sequence is important and there is a direct relationship between this order and the relationship of low-level descriptors with the semantics of the users

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Cette recherche décrit la représentation discursive que la présidente Dilma Rousseff fait de soi-même, dans son discours devant le Congrès National, lors de la journée d’investiture, le 1/1/2011. Notre travail se situe dans le domaine théorique et méthodologique de la linguistique du texte et, plus spécialement, dans la perspective de l’Analyse Textuelle des Discours – ATD (ADAM, 2011 [2008a]), qui se définit comme « une théorie de la production co(n)textuelle de sens qui doit se fonder sur l’analyse de textes concrets ». Elle nous fournit la notion théorique et analytique de « représentation discursive », qui se focalise sur la dimension sémantique du texte. Nous nous appuyons, aussi, sur des travaux récents sur les représentations discursives, réalisés dans la recherche brésilienne sur l’ATD (RODRIGUES, PASSEGGI, SILVA NETO, 2010, 2012; RAMOS, 2011; OLIVEIRA, 2013; QUEIROZ, 2013; ZAMBLANO-OLIVEIRA, PASSEGGI, 2013). Les principales opérations sémantiques de construction de la représentation discursive utilisées dans notre travail sont la Référenciation et la Prédication. L’approche méthodologique est, en même temps, qualitative et quantitative, priorisant l’identification des occurrences, ainsi que la description détaillée de leurs valeurs sémantiques et textuelles. Les résultats de la recherche sont de trois ordres : méthodologique, théorique et descriptif-interprétatif. Méthodologique : nous proposons une approche que nous désignons comme « marquage textuel » (ou « mappage textuel ») qui permet de marquer (étiqueter) les valeurs sémantiques des formes linguistiques, permettant leur identification dans le flux textuel, c.-à-d., dans la dimension séquentiellecompositionnelle du texte. Théorique : nous introduisons la notion de « domaines de la représentation discursive » qui organisent et articulent les différents éléments qui composent la représentation discursive de la présidente. Quant aux résultats descriptifsinterprétatifs du discours de l’investiture, ils indiquent que la représentation discursive de la présidente se configure au moyen de différents domaines conceptuels, explicités par les référenciations et les prédications. Ils mettent en relief les désignations et les actions / états, aussi bien de la femme – domaine du genre – que de la présidente – domaine du rôle politique et institutionnel. La présidente se représente explicitement et avec emphase comme l’agent responsable par les actions exprimées par les prédications verbales (verbes d’action), consciente de l’importance de son rôle politique et social. Les prédications nominales signalent clairement une représentation discursive qui englobe les domaines conceptuels politique, moral, éthique, comportemental et émotionnel (forte, accueillante, pionnière, consolidatrice, infatigable, humble, engagée, démocrate, victorieuse et courageuse). Le discours d’investiture réalise, donc, des désignations positives de la présidente, lesquelles se situent dans un temps présent et prospectif – avec des perspectives de futur – comme leader politique du Brésil, avec une participation active dans la transformation du pays, tenant compte aussi de son histoire de vie, sa biographie de luttes. Ainsi, la description empirique et l’interprétation de ce discours particulier contribue à l’analyse textuelle des représentations discursives dans le discours politique brésilien contemporain. Elle soulève, aussi, des questions théoriques et méthodologiques qui nous semblent pertinentes pour le développement de cette aproche.

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Leishmania infantum is the main etiologic agent of visceral leishmaniasis in the New World. The pattern of distribution of leishmaniasis has changed substantially and has presented an emerging profile within the periphery of the Large Urban Centers. Leishmania infection can compromise skin, mucosa and viscera. Only 10% of the individuals infected develop the disease and 90% of human infection is asymptomatic. The main factors involved in the development of the disease are the host immune response, the vector’s species and the parasite’s genetic content. The sequencing of Leishmania isolated seeks to increase the understanding of the symptoms of individuals. The aim of this study was to evaluate the genetic diversity of circulating Leishmania strains among humans, and symptomatic and asymptomatic, and dogs from endemic areas of Rio Grande do Norte State and analyze sandflies from endemic areas for cutaneous and visceral disease. The genetic variability was evaluated by the use of markers hsp70 , ITS1 and a whole genome sequencing was also carried out. The amplified hsp70 and ITS1 of samples were analyzed and assembled using a Phred / Phrap package. The dendograms were constructed using the same methodology, but adding 500 bootstraps, followed by inferences on the relationships between Leishmania variants. The sequences of the 20 Brazilian isolates were mapped to the reference genome L. infantum JPCM5, using the Bowtie2 program and the identification of 36 contigs. The information of the valid SNPs were used in the PCA. SNPs were visualized by Geneious 7.1 and IGV. The genome annotations were transferred to their respective chromosomes and displayed on Geneious. The matching sequences of all chromosomes were aligned using Mauve. The phylogenetic trees were calculated according to maximum likelihood and JTT models. Sandflies were analyzed by PCR for the identification of Leishmania infection, a blood meal source and GAPDH sand fly. As a result, hsp70 and ITS1 were not capable of identifying genetic variability among human isolates from symptomatic and asymptomatic, and dogs. The complete sequencing of the 20 Brazilian isolates revealed a strong similarity between the circulating Leishmania strains in Rio Grande do Norte. The isolates collected in the city of Natal from humans and canines remained grouped in all analyzes, suggesting that there is genotypic and geographic proximity among the isolates. The isolated samples in the 1990s had a higher genotypic diversity when compared to freshly isolated samples. All isolates presented 36 chromosomes with variable ploidy among them, no correlation was found between the number of amastina genes copies, gp63, A2 and SSG with such clinic forms. In general, we did not find correlation between symptomatic and asymptomatic clinical forms and the gene content of the Brazilian isolates of Leishmania. 34,28% of the sandflies collected in the upper west region were L. longipalpis and the main sources of blood meal were humans, dogs and chickens.

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Leishmania infantum is the main etiologic agent of visceral leishmaniasis in the New World. The pattern of distribution of leishmaniasis has changed substantially and has presented an emerging profile within the periphery of the Large Urban Centers. Leishmania infection can compromise skin, mucosa and viscera. Only 10% of the individuals infected develop the disease and 90% of human infection is asymptomatic. The main factors involved in the development of the disease are the host immune response, the vector’s species and the parasite’s genetic content. The sequencing of Leishmania isolated seeks to increase the understanding of the symptoms of individuals. The aim of this study was to evaluate the genetic diversity of circulating Leishmania strains among humans, and symptomatic and asymptomatic, and dogs from endemic areas of Rio Grande do Norte State and analyze sandflies from endemic areas for cutaneous and visceral disease. The genetic variability was evaluated by the use of markers hsp70 , ITS1 and a whole genome sequencing was also carried out. The amplified hsp70 and ITS1 of samples were analyzed and assembled using a Phred / Phrap package. The dendograms were constructed using the same methodology, but adding 500 bootstraps, followed by inferences on the relationships between Leishmania variants. The sequences of the 20 Brazilian isolates were mapped to the reference genome L. infantum JPCM5, using the Bowtie2 program and the identification of 36 contigs. The information of the valid SNPs were used in the PCA. SNPs were visualized by Geneious 7.1 and IGV. The genome annotations were transferred to their respective chromosomes and displayed on Geneious. The matching sequences of all chromosomes were aligned using Mauve. The phylogenetic trees were calculated according to maximum likelihood and JTT models. Sandflies were analyzed by PCR for the identification of Leishmania infection, a blood meal source and GAPDH sand fly. As a result, hsp70 and ITS1 were not capable of identifying genetic variability among human isolates from symptomatic and asymptomatic, and dogs. The complete sequencing of the 20 Brazilian isolates revealed a strong similarity between the circulating Leishmania strains in Rio Grande do Norte. The isolates collected in the city of Natal from humans and canines remained grouped in all analyzes, suggesting that there is genotypic and geographic proximity among the isolates. The isolated samples in the 1990s had a higher genotypic diversity when compared to freshly isolated samples. All isolates presented 36 chromosomes with variable ploidy among them, no correlation was found between the number of amastina genes copies, gp63, A2 and SSG with such clinic forms. In general, we did not find correlation between symptomatic and asymptomatic clinical forms and the gene content of the Brazilian isolates of Leishmania. 34,28% of the sandflies collected in the upper west region were L. longipalpis and the main sources of blood meal were humans, dogs and chickens.