860 resultados para Feature nasal
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Although nontechnical losses automatic identification has been massively studied, the problem of selecting the most representative features in order to boost the identification accuracy and to characterize possible illegal consumers has not attracted much attention in this context. In this paper, we focus on this problem by reviewing three evolutionary-based techniques for feature selection, and we also introduce one of them in this context. The results demonstrated that selecting the most representative features can improve a lot of the classification accuracy of possible frauds in datasets composed by industrial and commercial profiles.
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Abstract Background One goal of gene expression profiling is to identify signature genes that robustly distinguish different types or grades of tumors. Several tumor classifiers based on expression profiling have been proposed using microarray technique. Due to important differences in the probabilistic models of microarray and SAGE technologies, it is important to develop suitable techniques to select specific genes from SAGE measurements. Results A new framework to select specific genes that distinguish different biological states based on the analysis of SAGE data is proposed. The new framework applies the bolstered error for the identification of strong genes that separate the biological states in a feature space defined by the gene expression of a training set. Credibility intervals defined from a probabilistic model of SAGE measurements are used to identify the genes that distinguish the different states with more reliability among all gene groups selected by the strong genes method. A score taking into account the credibility and the bolstered error values in order to rank the groups of considered genes is proposed. Results obtained using SAGE data from gliomas are presented, thus corroborating the introduced methodology. Conclusion The model representing counting data, such as SAGE, provides additional statistical information that allows a more robust analysis. The additional statistical information provided by the probabilistic model is incorporated in the methodology described in the paper. The introduced method is suitable to identify signature genes that lead to a good separation of the biological states using SAGE and may be adapted for other counting methods such as Massive Parallel Signature Sequencing (MPSS) or the recent Sequencing-By-Synthesis (SBS) technique. Some of such genes identified by the proposed method may be useful to generate classifiers.
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This review is addressed two pathophysiologic mechanisms implicated in the pathogenesis of nasal polyposis: the unique remodeling process found in nasal polyp tissue and the immune response of patients with nasal polyposis to Staphylococcus aureus. These two theories converge to the same direction in different aspects, including decreased extracellular matrix production, impaired T regulation and favoring of a Th2 immune response. In patients with nasal polyposis, an exaggerated immune response to Staphylococcus aureus may aggravate the airway remodeling process.
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INTRODUÇÃO: O espelho de Glatzel modificado é capaz de avaliar o fluxo nasal expiratório; entretanto, há pouca informação sobre esse método e sua utilização na mensuração objetiva da patência nasal após procedimentos cirúrgicos. OBJETIVO: Comparar, através de estudo prospectivo, os resultados funcionais antes e depois de uma rinoplastia e avaliar a utilização do espelho de Glatzel como método objetivo na avaliação da patência nasal. Para esse fim, analisamos os resultados funcionais da cirurgia mediante questionário subjetivo e medidas objetivas através do espelho de Glatzel, e avaliamos a correlação entre os dois métodos. MÉTODO: Vinte pacientes (14 mulheres e 6 homens) foram submetidos à rinoplastia estética com uso de enxertos expansores. Avaliação pré e pós-operatória (90 a 120 dias) incluíram um escore de qualidade respiratória (subjetiva) e o teste do espelho de Glatzel modificado (objetiva). O teste de Spearman foi utilizado para comparar os dados subjetivos e objetivos. RESULTADOS: A avaliação subjetiva demonstrou diferença estatística (antes da cirurgia, 8 ± 2; após cirurgia, 9.4 ± 0.7; P < .001). Não houve diferença estatística nas médias da patência nasal mediante espelho de Glatzel. Não houve correlação estatisticamente significante quando comparados os valores do espelho de Glatzel com os escores referidos pelos pacientes durante avaliação subjetiva, seja no pré ou pós-operatório. CONCLUSÃO: O método de Glatzel não demonstrou significância estatística, em contraste com a avaliação subjetiva, que demonstrou melhora significativa na qualidade respiratória, sugerindo que o método de Glatzel não possui sensibilidade na detecção de pequenas mudanças anatômicas da cavidade nasal.
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INTRODUÇÃO: O cisto nasolabial é uma doença rara, normalmente unilateral, benigna, de origem embrionária, localizada em partes moles da região do sulco nasolabial e asa nasal. O diagnóstico é essencialmente clínico, levando em consideração a topografia do cisto, que geralmente é assintomático. OBJETIVO: Este artigo tem como objetivo principal à descrição de um caso incomum de cisto nasolabial bilateral com obstrução nasal, seu tratamento, aspectos anatomopatológicos e acompanhamento, além de revisão de literatura. RELATO DO CASO: Paciente do sexo feminino, parda, 24 anos de idade, apresentando abaulamento em região nasolabial e obstrução nasal. Exames físico e complementares compatíveis com cisto nasolabial. Indicado tratamento cirúrgico para exérese da lesão. CONSIDERAÇÕES FINAIS: O cisto nasolabial bilateral, apesar de raro, é uma possível causa de obstrução nasal, com boa resposta à terapia cirúrgica.
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O nariz ocupa o centro da face, o que torna pequenas assimetrias e imperfeições evidentes. Uma de suas subunidades é a asa nasal, região que exige não apenas resultados estéticos, mas também funcionais, em sua reconstrução, tornando-se um desafio ao cirurgião plástico. Neste artigo são descritos 3 casos em que foi utilizado enxerto composto auricular para reconstrução da asa nasal. Os enxertos apresentaram integração total, com resultados estéticos e funcionais adequados. Segundo revisão da literatura, não há diferença nos índices de complicação comparando-se os enxertos com os retalhos locais e, a longo prazo, a cartilagem auricular tende a manter-se no formato moldado, sofrendo raras distorções e mínima ou nenhuma absorção, diferentemente das cartilagens costais e dos enxertos ósseos. O enxerto composto auricular é uma técnica versátil e segura, com excelentes resultados na reconstrução da asa nasal e com baixa morbidade das áreas doadoras, cumprindo com eficiência seu objetivo reparador.
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OBJECTIVE: To assess the effects of rapid maxillary expansion on facial morphology and on nasal cavity dimensions of mouth breathing children by acoustic rhinometry and computed rhinomanometry. METHODS: Cohort; 29 mouth breathing children with posterior crossbite were evaluated. Orthodontic and otorhinolaryngologic documentation were performed at three different times, i.e., before expansion, immediately after and 90 days following expansion. RESULTS: The expansion was accompanied by an increase of the maxillary and nasal bone transversal width. However, there were no significant differences in relation to mucosal area of the nose. Acoustic rhinometry showed no difference in the minimal cross-sectional area at the level of the valve and inferior turbinate between the periods analyzed, although rhinomanometry showed a statistically significant reduction in nasal resistance right after expansion, but were similar to pre-treatment values 90 days after expansion. CONCLUSION: The maxillary expansion increased the maxilla and nasal bony area, but was inefficient to increase the nasal mucosal area, and may lessen the nasal resistance, although there was no difference in nasal geometry. Significance: Nasal bony expansion is followed by a mucosal compensation.
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Abstract Background Xanthomonads are plant-associated bacteria responsible for diseases on economically important crops. Xanthomonas fuscans subsp. fuscans (Xff) is one of the causal agents of common bacterial blight of bean. In this study, the complete genome sequence of strain Xff 4834-R was determined and compared to other Xanthomonas genome sequences. Results Comparative genomics analyses revealed core characteristics shared between Xff 4834-R and other xanthomonads including chemotaxis elements, two-component systems, TonB-dependent transporters, secretion systems (from T1SS to T6SS) and multiple effectors. For instance a repertoire of 29 Type 3 Effectors (T3Es) with two Transcription Activator-Like Effectors was predicted. Mobile elements were associated with major modifications in the genome structure and gene content in comparison to other Xanthomonas genomes. Notably, a deletion of 33 kbp affects flagellum biosynthesis in Xff 4834-R. The presence of a complete flagellar cluster was assessed in a collection of more than 300 strains representing different species and pathovars of Xanthomonas. Five percent of the tested strains presented a deletion in the flagellar cluster and were non-motile. Moreover, half of the Xff strains isolated from the same epidemic than 4834-R was non-motile and this ratio was conserved in the strains colonizing the next bean seed generations. Conclusions This work describes the first genome of a Xanthomonas strain pathogenic on bean and reports the existence of non-motile xanthomonads belonging to different species and pathovars. Isolation of such Xff variants from a natural epidemic may suggest that flagellar motility is not a key function for in planta fitness.
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[EN]The human face provides useful information during interaction; therefore, any system integrating Vision- BasedHuman Computer Interaction requires fast and reliable face and facial feature detection. Different approaches have focused on this ability but only open source implementations have been extensively used by researchers. A good example is the Viola–Jones object detection framework that particularly in the context of facial processing has been frequently used.
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[EN]In this paper, we experimentally study the combination of face and facial feature detectors to improve face detection performance. The face detection problem, as suggeted by recent face detection challenges, is still not solved. Face detectors traditionally fail in large-scale problems and/or when the face is occluded or di erent head rotations are present. The combination of face and facial feature detectors is evaluated with a public database. The obtained results evidence an improvement in the positive detection rate while reducing the false detection rate. Additionally, we prove that the integration of facial feature detectors provides useful information for pose estimation and face alignment.
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The identification of people by measuring some traits of individual anatomy or physiology has led to a specific research area called biometric recognition. This thesis is focused on improving fingerprint recognition systems considering three important problems: fingerprint enhancement, fingerprint orientation extraction and automatic evaluation of fingerprint algorithms. An effective extraction of salient fingerprint features depends on the quality of the input fingerprint. If the fingerprint is very noisy, we are not able to detect a reliable set of features. A new fingerprint enhancement method, which is both iterative and contextual, is proposed. This approach detects high-quality regions in fingerprints, selectively applies contextual filtering and iteratively expands like wildfire toward low-quality ones. A precise estimation of the orientation field would greatly simplify the estimation of other fingerprint features (singular points, minutiae) and improve the performance of a fingerprint recognition system. The fingerprint orientation extraction is improved following two directions. First, after the introduction of a new taxonomy of fingerprint orientation extraction methods, several variants of baseline methods are implemented and, pointing out the role of pre- and post- processing, we show how to improve the extraction. Second, the introduction of a new hybrid orientation extraction method, which follows an adaptive scheme, allows to improve significantly the orientation extraction in noisy fingerprints. Scientific papers typically propose recognition systems that integrate many modules and therefore an automatic evaluation of fingerprint algorithms is needed to isolate the contributions that determine an actual progress in the state-of-the-art. The lack of a publicly available framework to compare fingerprint orientation extraction algorithms, motivates the introduction of a new benchmark area called FOE (including fingerprints and manually-marked orientation ground-truth) along with fingerprint matching benchmarks in the FVC-onGoing framework. The success of such framework is discussed by providing relevant statistics: more than 1450 algorithms submitted and two international competitions.
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Alzheimer's disease (AD) is a fatal neurodegenerative condition characterized clinically by progressive memory loss and irreversible cognitive deterioration. It has been shown that there is a progressive degeneration of the brain cholinergic neurons which leads to the appearance of cognitive symptoms of the disease. The aim of this work was the formulation of multifunctional nanocarriers for nasal administration of tacrine-HCl (THA). This route has many advantages; in particular is possible to convey the drug directly to the Central Nervous System, through the olfactory bulb. In particular, were prepared Albumin nanoparticles carrying beta cyclodextrin and two different beta cyclodextrin derivatives (hydroxypropyl beta cyclodextrin and sulphobutylether beta cyclodextrin), and Multifunctional liposomes, prepared using traditional excipients (cholesterol and phosphatidylcholine), partly enriched with α-tocopherol (Toc) and/or polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid) (Ω3). Both nanosystems were characterized in terms of size, Zeta potential and encapsulation efficiency. Were also evaluated their functional properties such as mucoadhesion and permeability, using an ex-vivo assay based on nasal sheep mucosa. On Liposomes were also assessed drug neuronal uptake, cell toxicity, antioxidant and, cytoprotective activity in the human neuronal cell line SH-SY5Y and finally tocopherol trans-membrane diffusion. Both the nanocarriers produced presented excellent properties and a high potential as new systems for CNS-delivery of anti-Alzheimer drugs via the nasal route.
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Data sets describing the state of the earth's atmosphere are of great importance in the atmospheric sciences. Over the last decades, the quality and sheer amount of the available data increased significantly, resulting in a rising demand for new tools capable of handling and analysing these large, multidimensional sets of atmospheric data. The interdisciplinary work presented in this thesis covers the development and the application of practical software tools and efficient algorithms from the field of computer science, aiming at the goal of enabling atmospheric scientists to analyse and to gain new insights from these large data sets. For this purpose, our tools combine novel techniques with well-established methods from different areas such as scientific visualization and data segmentation. In this thesis, three practical tools are presented. Two of these tools are software systems (Insight and IWAL) for different types of processing and interactive visualization of data, the third tool is an efficient algorithm for data segmentation implemented as part of Insight.Insight is a toolkit for the interactive, three-dimensional visualization and processing of large sets of atmospheric data, originally developed as a testing environment for the novel segmentation algorithm. It provides a dynamic system for combining at runtime data from different sources, a variety of different data processing algorithms, and several visualization techniques. Its modular architecture and flexible scripting support led to additional applications of the software, from which two examples are presented: the usage of Insight as a WMS (web map service) server, and the automatic production of a sequence of images for the visualization of cyclone simulations. The core application of Insight is the provision of the novel segmentation algorithm for the efficient detection and tracking of 3D features in large sets of atmospheric data, as well as for the precise localization of the occurring genesis, lysis, merging and splitting events. Data segmentation usually leads to a significant reduction of the size of the considered data. This enables a practical visualization of the data, statistical analyses of the features and their events, and the manual or automatic detection of interesting situations for subsequent detailed investigation. The concepts of the novel algorithm, its technical realization, and several extensions for avoiding under- and over-segmentation are discussed. As example applications, this thesis covers the setup and the results of the segmentation of upper-tropospheric jet streams and cyclones as full 3D objects. Finally, IWAL is presented, which is a web application for providing an easy interactive access to meteorological data visualizations, primarily aimed at students. As a web application, the needs to retrieve all input data sets and to install and handle complex visualization tools on a local machine are avoided. The main challenge in the provision of customizable visualizations to large numbers of simultaneous users was to find an acceptable trade-off between the available visualization options and the performance of the application. Besides the implementational details, benchmarks and the results of a user survey are presented.