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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.
291

Aspectos clínicos e laboratoriais dos pacientes portadores de imunodeficiência comum variável atendidos em ambulatórios terciários de imunologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo / Clinical and laboratory features of common variable immunodeficiency patients seen at immunology outpatient clinics of Ribeirão Preto Medical School Hospital - University of São Paulo

Rodero, Maíra Ribeiro 19 May 2017 (has links)
Imunodeficiência Comum Variável (ICV) é uma imunodeficiência primária de igual distribuição entre os sexos e que afeta crianças e adultos, caracterizada por hipogamaglobulinemia com susceptibilidade aumentada a infecções e ampla variedade de complicações não infecciosas, como autoimunidade, malignidade, hiperplasia linfoide, doenças gastrointestinais, dentre outras. Os objetivos deste estudo foram: avaliar as manifestações clínicas, infecciosas e não infecciosas, mais frequentes em portadores de ICV (antes e após início da terapia com reposição de imunoglobulina humana) acompanhados em ambulatórios de imunologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP), além dos níveis séricos de imunoglobulinas (IgG, IgA e IgM) ao diagnóstico, bem como as alterações quantitativas de células CD19+, CD3+CD4+, CD3+CD8+ e CD3-CD16+CD56+ desses pacientes. Neste estudo descritivo foram obtidas informações de pacientes com ICV acompanhados no HCFMRPUSP, através de registros de prontuários médicos. Foram avaliados 32 pacientes: 19 do sexo masculino e 13 do sexo feminino. A mediana da idade de início dos sintomas foi de 8,5 anos, com um pico de incidência precoce. O tempo médio de atraso para o diagnóstico foi de 7,7 anos. Todos os pacientes apresentaram infecções recorrentes, que levaram ao diagnóstico da ICV. As infecções mais frequentes foram as respiratórias, sendo que antes do diagnóstico as pneumonias foram as mais observadas (gerando, inclusive, grande número de internações) e durante o primeiro ano de uso regular da terapia de reposição com imunoglobulina humana as rinossinusites foram as que mais ocorreram. Houve redução na incidência de infecções após início do tratamento. Todos os pacientes apresentaram níveis séricos de IgG, IgA e IgM reduzidos ao diagnóstico, sendo que as medianas dos níveis séricos foram de 158 mg/dL, 10,15 mg/dL e 17 mg/dL, respectivamente. De 30 pacientes que haviam realizado imunofenotipagem, cerca de 73% apresentaram número absoluto reduzido de células CD19+ e 40% apresentaram número absoluto reduzido de linfócitos T CD4+. A relação CD4/CD8 foi invertida em aproximadamente 53% dos pacientes. Em 18 pacientes as células natural killer foram quantificadas e cerca de 56% deles apresentaram número absoluto reduzido. A maioria (97%) dos pacientes manifestou, no mínimo, uma comorbidade não infecciosa no tempo médio de seguimento de 8,2 anos, sendo que hiperplasia linfoide e doença pulmonar crônica foram as mais frequentes, cada uma ocorrendo em cerca de metade dos pacientes. O atraso para o diagnóstico da ICV foi importante, sugerindo que a presença de infecções recorrentes, especialmente do trato respiratório, deveria levar à investigação de deficiências de anticorpos, com dosagem de imunoglobulinas. Complicações não infecciosas foram extremamente comuns nesta casuística, ressaltando o amplo espectro clínico da doença. / Common variable immunodeficiency (CVID) is a primary immunodeficiency that is equally distributed between men and women and affects children and adults, characterized by hypogammaglobulinemia with increased susceptibility to infections and a wide variety of noninfectious complications such as autoimmunity, malignancy, lymphoid hyperplasia, gastrointestinal diseases, among others. The purposes of this study were to evaluate infectious and non-infectious clinical manifestations (before and after immunoglobulin replacement therapy) of CVID patients attended at immunology outpatient clinics of the Clinical Hospital of Ribeirão Preto Medical School - University of São Paulo (HCFMRP-USP), in addition to immunoglobulins (IgG, IgA and IgM) serum levels at diagnosis, as well as quantitative differences in CD19+, CD3+CD4+, CD3+CD8+ and CD3-CD16+CD56+ cells. In this descriptive study, data of CVID patients followed up at HCFMRP-USP were collected through medical records. Thirty-two patients were found: 19 males and 13 females. The median age of onset of symptoms was 8.5 years, with an early peak of incidence. The mean delay for diagnosis was 7.7 years. All patients had recurrent infections, which led to the diagnosis of CVID. The most frequent infections were respiratory tract infections. Pneumonias were more observed before the diagnosis (generating a large number of hospitalizations) and rhinosinusitis were more frequent during the first year under regular use of immunoglobulin replacement therapy. There was a reduction in the incidence of infections after initiation of treatment. All patients had low IgG, IgA and IgM serum levels (lower than the 3th percentile for age) at diagnosis and the median of serum levels were 158 mg/dL, 10.15 mg/dL and 17 mg/dL, respectively. Among 30 patients that had been immunophenotyped, approximately 73% had a reduced absolute number of CD19+ cells and 40% had a reduced absolute number of T CD4+ lymphocytes. The CD4/CD8 ratio was inverted in approximately 53% of the patients. Natural killer cells were quantified in 18 patients and about 56% of them had reduced absolute number. The majority (97%) of patients manifested at least one noninfectious comorbidity at a mean follow-up time of 8.2 years, with lymphoid hyperplasia and chronic lung disease being the most common, each occurring in about half of the patients. The delay for the diagnosis of CVID was important, suggesting that the presence of recurrent infections, especially of the respiratory tract, should lead to the investigation of antibody deficiencies with dosage of immunoglobulins. Noninfectious complications were extremely common in this series, highlighting the broad clinical spectrum of the disease.
292

Despite Having More Advanced Features, Hearing Aids Hold Line on Retail Price

Johnson, Earl E. 01 January 2008 (has links)
Despite the growing popularity of state-of-the-art open-canal mini-BTEs, which were discussed in last month's Cover Story, and the increasing prevalence of advanced hearing aid features, the annual Hearing Journal/Audiology Onlinedispenser survey conducted in January found only small, inflation-appropriate increases in the average retail price of hearing aids over the past 3 years. Specifically, the average price of the hearing aids that participating dispensers reported selling in 2007 was $1986, only marginally higher than the average prices of $1912 and $1868 in 2006 and 2005, respectively. Retail pricing is just one of many topics addressed in this, the second of two articles reporting the results of the 2008 dispenser survey. The March article focused on a special section of the survey exploring the experiences and attitudes of dispensing audiologists and hearing instrument specialists related to open-canal mini-BTE hearing aids. This article reports key findings from the rest of the Internet survey, which drew valid responses from 418 hearing healthcare professionals, including 291 audiologists and 120 traditional dispensers.
293

Elaboration de critères prosodiques pour une évaluation semi-automatique des apprenants francophones de l'anglais / Devising prosodic criteria for a semi-automatic assessment of Francophone learners of English

Cauvin, Evelyne 04 December 2017 (has links)
L’objectif de cette thèse est de modéliser l’interlangue prosodique des apprenants francophones de l’anglais afin de pouvoir élaborer des critères utilisables pour une évaluation semi-automatique de leur niveau prosodique. Le domaine évaluatif requiert la plus grande rigueur dans la mise en place de ses critères pour aboutir à la validité, la fiabilité, la faisabilité et l’équité maximales, alors que la prosodie anglaise de la langue cible se caractérise par son extrême variabilité. Aussi, peu d’études se sont engagées dans l’évaluation de la prosodie, qui représente une réelle gageure. Pour relever ce défi, une stratégie particulière a été mise en place pour élaborer une méthodologie permettant d’atteindre l’objectif fixé, en lecture.L’approche choisie repose sur la symbiose permanente qu’entretient la prosodie avec le monde dans lequel évolue le locuteur. Cette méthodologie, ou « profilage », est destinée à sélectionner par inclusion ou exclusion les éléments analysés tant au niveau perceptif qu’acoustique. Le profilage des réalisations sur l’axe syntagmatique permet de sélectionner les locuteurs natifs servant de modèles, et celui basé sur le phénomène d’emphase rend possible un ciblage de leurs réalisations les plus pertinentes à modéliser sur l’axe paradigmatique. Conformément à cette méthodologie d’investigation nouvelle et aux résultats perceptifs et acoustiques concordants pour la langue cible, les réalisations des apprenants francophones du corpus Longdale-Charliphonia sont analysés acoustiquement. Le classement automatique à partir des variables prosodiques (acoustiques et perceptives) est confronté à celui d’experts évaluant par perception classique.Les travaux de cette thèse aboutissent essentiellement à : Une modélisation de la prosodie anglaise non native par grilles évaluatives critériées s’appuyant sur critères distinctifs natifs et non natifs issus de variables temporelles (vitesse d’élocution avec ou sans pauses), de registre et de mélodie, ainsi que de rythme, À partir de ces variables, une évaluation semi-automatisée de 15 apprenants représentatifs du corpus par classement et notation, une correspondance des résultats de l’évaluation traditionnelle avec celle semi-automatique évoluant entre 56,83% et 59,74% dans une catégorisation des apprenants en 3 niveaux de maîtrise, en fonction du profilage d’experts évaluateurs. / The aim of our study is to modelise the prosodic interlanguage of Francophone learners of English in order to provide useful criteria for a semi-automatic assessment of their prosodic level in English. Learner assessment is a field that requires to be very rigorous and fair when setting up criteria that ensure validity, reliability, feasibility and equality, whereas English prosody is highly variable. Hence, few studies have carried out research in assessing prosody because it represents a real challenge. To address this issue, a specific strategy has been devised to elaborate a methodology that would ensure assessing a reading task successfully.The approach relies upon the constant symbiosis between prosody and a speaker’s subjective response to their environment. Our methodology, also known as « profiling », first aims at selecting relevant native perceived and acoustic prosodic features that will optimize assessment criteria by using their degree of emphasis and creating speakers’ prosodic profiles. Then, using the Longdale-Charliphonia corpus, the learner's productions are analysed acoustically. The automatic classification of the learners based on acoustic or perception prosodic variables is then submitted to expert aural assessment which assesses the learner evaluation criteria.This study achieves: A modelisation of non-native English prosody based on assessment grids that rely upon features of both native and non-native speakers of English, namely, speech rate – with or without the inclusion of pauses, register, melody and rhythm,A semi-automatic evaluation of 15 representative learners based on the above modelisation – ranking and marking,A comparison of the semi-automatic results with those of experts' auditory assessment; correspondence between the two varies from 56.83% to 59.74% when categorising the learners into three prosodic proficiency groups.
294

People Matching for Transportation Planning Using Optimized Features and Texel Camera Data for Sequential Estimation

Wang, Ziang 01 May 2012 (has links)
This thesis explores pattern recognition in the dynamic setting of public transportation, such as a bus, as people enter and later exit from a doorway. Matching the entrance and exit of each individual provides accurate information about individual riders such as how long a person is on a bus and which stops the person uses. At a higher level, matching exits to entries provides information about the distribution of traffic flow across the whole transportation system. A texel camera is implemented and multiple measures of people are made where the depth and color data are generated. A large number of features are generated and the sequential floating forward selection (SFFS) algorithm is used for selecting the optimized features. Criterion functions using marginal accuracy and maximization of minimum normalized Mahalanobis distance are designed and compared. Because of the particular case of the bus environment, which is a sequential estimation problem, a trellis optimization algorithm is designed based on a sequence of measurements from the texel camera. Since the number of states in the trellis grows exponentially with the number of people currently on the bus, a beam search pruning technique is employed to manage the computational and memory load. Experimental results using real texel camera measurements show good results for 68 people exiting from an initially full bus in a randomized order. In a bus route simulation where a true traffic flow distribution is used to randomly draw entry and exit events for simulated riders, the proposed sequential estimation algorithm produces an estimated traffic flow distribution which provides an excellent match to the true distribution.
295

CHARACTERIZATION OF NANOSTRUCTURE, MATERIALS, AND ELECTRON EMISSION PERFORMANCE OF NEXT-GENERATION THERMIONIC SCANDATE CATHODES

Liu, Xiaotao 01 January 2019 (has links)
Scandate cathodes, where scandia is added to the tungsten cathode pellets, have recently received substantial and renewed research interest owing to significantly improved electron emission capabilities at lower temperatures, as compared with conventional dispenser cathodes. However, there are several persistent issues including non-uniform electron emission, lack of understanding regarding scandium’s role in the emission mechanism, and unreliable reproducibility in terms of scandate cathode fabrication. As a result, scandate cathodes have not yet been widely implemented in actual vacuum electron devices (VEDs). The surface structure and chemical composition of multiple scandate cathodes – prepared with the powder using the liquid-solid (L-S) technique – and exhibiting excellent emission behavior were characterized to give insight into the fundamental mechanism(s) of operation. This was achieved with high-resolution electron microscopy techniques that include high-precision specimen lift-out. These studies showed that the micron-sized tungsten particles that compose the largest fraction of the cathode body are highly faceted and decorated with nanoscale Ba/BaO (~10 nm), as well as larger (~150 nm) Sc2O3 and BaAl2O4 particles. The experimentally identified facets were confirmed through Wulff analysis of the tungsten crystal shape and were determined to consist of {110}, {100}, and {112} facets, in increasing order of surface area prevalence. Furthermore, it is estimated that Ba atoms decorating the tungsten crystal surfaces are present in quantities such that monolayer coverage is possible at elevated temperatures. The high-resolution electron microscopy techniques used to investigate the cross section (near-surface) of the L-S scandate cathodes also revealed that the BaAl2O4 particles (100-500 nm) that attach to the larger tungsten particles are either adjacent to the smaller Sc2O3 nanoparticles or encompass them. Furthermore, high-resolution chemical analysis and 3D elemental tomography show that the two oxides always appear to be physically distinct from each other, despite their close proximity. 3D elemental tomography also showed that the Sc2O3 particles can sometimes appear inside the larger tungsten particles, but are inhomogeneously distributed. Nanobeam electron diffraction confirmed that the crystal structure of the tungsten particles are body-centered cubic, and imply that the structure remains unchanged despite the numerous complex chemical reactions that take place throughout the impregnation and activation procedures. The role of Sc and the emission mechanism for scandate cathodes are discussed. Based on characterization results and materials computation, the role of Sc in scandate cathodes is possibly related to tuning the partial pressure of oxygen in order to establish an oxygen-poor atmosphere around the cathode surface, which is a necessary condition for the formation of the (near) equilibrium tungsten shape. A thin Ba-Sc-O surface layer (~8 nm) was detected near the surface of tungsten particles, using electron energy loss spectroscopy in the scanning transmission electron microscope. This stands in stark contrast to models invoking a ~100 nm Ba-Sc-O semiconducting surface layer, which are broadly discussed in the literature. These results provide new insights into understanding the emission mechanism of scandate cathodes.
296

Knowledge Graph Representation Learning: Approaches and Applications in Biomedicine

AlShahrani, Mona 13 November 2019 (has links)
Bio-ontologies and Linked Data have become integral part of biological and biomedical knowledge bases with over 500 of them and millions of triples. Such knowledge bases are primarily developed for information retrieval, query processing, data integration, standardization, and provision. Developing machine learning methods which can exploit the background knowledge in such resources for predictive analysis and novel discovery in the biomedical domain has become essential. In this dissertation, we present novel approaches which utilize the plethora of data sets made available as bio-ontologies and Linked Data in a single uni ed framework as knowledge graphs. We utilize representation learning with knowledge graphs and introduce generic models for addressing and tackling computational problems of major implications to human health, such as predicting disease-gene associations and drug repurposing. We also show that our methods can compensate for incomplete information in public databases and can smoothly facilitate integration with biomedical literature for similar prediction tasks. Furthermore, we demonstrate that our methods can learn and extract features that outperform relevant methods, which rely on manually crafted features and laborious features engineering and pre-processing. Finally, we present a systematic evaluation of knowledge graph representation learning methods and demonstrate their potential applications for data analytics in biomedicine.
297

Překlad povídky J. D. Salingera Dokonalý den pro banánové rybičky. Lingvostylistická analýza / J. D. Salinger's "A Perfect Day for Bananafish" Translation. Linguo-stylistic Analysis

Válková, Veronika January 2019 (has links)
This thesis aims to analyse several translations of J.D. Salinger's short story A Perfect Day for Bananafish: namely two translations and two edited versions of the latter one. The contrastive view is used to discern the main differences in meaning of the original and the translated texts. There are several points of view adopted to recognise the differences. On the syntactic level, the contrast between the texts was found to be present in the treatment of the author's style, predominantly in the narrative perspective. Not employing nominal structures a great deal, the author's style was not lost in the translation process. Comparing the translated texts, a tendency to adhere to the syntactic surface structure of the original text was found in the less recent versions. Another level of analysis explored the temporal relations of the texts, with the original text relying mostly on structures expressing sequences of events and also simultaneity of events, but not the perfective aspect to a great degree. These time relations are also found to be communicated in the translated texts successfully. It is not only the narrator that is discussed in this thesis, as a great portion of the short story consist of dialogues. The analysis aimed, using certain excerpts of the story, to find to what degree...
298

[en] FRACTURE RESISTENCE OF THE GRADE R4 STRUCTURAL STEEL AND ITS DEPENDENCE WITH THE QUENCHING TEMPERATURE / [pt] RESISTÊNCIA À FRATURA DO AÇO ESTRUTURAL R4 E SUA DEPENDÊNCIA COM A TEMPERATURA DE TÊMPERA

ROBERTO ANTONIO ROCO ANTUNEZ 03 April 2006 (has links)
[pt] O presente trabalho apresenta um estudo da influência dos tratamentos térmicos de têmpera e revenido sôbre a resistência à fratura do aço estrutural R4, adotado na fabricação de elos para sistemas de ancoragem de unidade offshore e soldados pelo processo de centelhamento. Corpos de prova do tipo CT foram retirados da região da solda dos elos, usinados com orientação L-R e submetidos a diferentes tratamentos térmicos de têmpera (temperaturas de austenitização de 810, 840, 870 e 900ºC) e revenido (640 e 680ºC), num total de quatro condições microestruturais. Após pré-trincamento em fadiga, os corpos de prova foram submetidos a carregamento monotônico em tração, com o objetivo de se determinar a resistência à fratura do material com base no parâmetro CTOD (Crack Tip Opening Displacement). Os resultados do ensaio de CTOD demonstraram que houve uma redução da resistência à fratura do aço estrutural R4 com o aumento da temperatura de austenitização (810, 840 e 870°C) e temperatura de revenido de 640°C. Entretanto, para maiores temperaturas de austenitização (900°C) e revenido (680°C), houve um aumento do parâmetro CTOD. Modificações microestruturais no material causadas pelos tratamentos térmicos foram associadas com as variações da tenacidade. / [en] This study has been made concerning the influence of quenching and tempering heat treatments on the fracture resistance of a grade R4 structural steel, largely used for fabricating offshore mooring chains by flash welding. CT specimens were taken from the welded joints region in L-R and machined following orientation and subjected to different quenching (austenizing temperatures of 810, 840, 870 and 900ºC) and tempering (640 ºC and 680ºC) treatments, in a total of four microstructural conditions. After fatigue precracking, the specimens were monotonically loaded in tension in order to determine the fracture resistance of the material on the basis of the CTOD (Crack Tip Opening Displacement) parameter. The results of the CTOD tests showed that the fracture resistance of the grade R4 structural steel has decreased when increasing the austenitizing temperature (810, 840 and 870°C) and tempering at 640ºC. However, when adopting higher austenitizing (900°C) and tempering (680° C) temperatures, the parameter CTOD has increased. The microstructural modifications caused by the heat treatments were associated with the toughness modifications.
299

Fundamental Features of Fostering Teacher Collective Efficacy: Principals’ Attitudes, Behaviors, and Practices

Nordick, Shelley 01 August 2017 (has links)
The purpose of this study was to explore the attitudes, practices, and behaviors of principals who foster teacher collective efficacy. The research questions were developed based upon Bandura’s social cognitive theory to include (a) what are the attitudes held by principals that influence TCE; (b) what are the behaviors enacted by principals that influence TCE; (c) what are the practices employed by principals that influence TCE. The study utilized a qualitative approach with a multisite case study design. The Collective Teacher Efficacy Scale developed by Goddard et al. was used to measure TCE of participating schools. The survey results were analyzed to facilitate the selection of four cases. Data were gathered through semistructured interviews from the principal and three to five teachers at each school. The data from each interview were developed through content analysis and then examined in relation to all other interviews in a cross-case analysis. The results presented fundamental attitudes, behaviors, and practices principals used in fostering collective efficacy. Principals held attitudes that student success was a top priority, as well as attitudes of responsibility, caring, shared purpose, confidence, and collaboration. Principal behaviors included supporting teachers, communicating, knowing teachers, and modeling desired behaviors. Principal practices included establishing an environment of openness and support, establishing shared expectations, facilitating teacher voice, providing opportunities to collaborate, and promoting continuous learning.
300

[en] ESTIMATING AND FORECASTING IN VAR MODELS WHITH SHORT-RUN AND LONG-RUN RESTRICTIONS: A MONTE CARLO STUDY / [pt] ESTIMAÇÃO E PREVISÃO EM MODELOS VAR COM RESTRIÇÕES DE CURTO E LONGO PRAZO: UM ESTUDO MONTE CARLO

CARLOS ENRIQUE CARRASCO GUTIERREZ 29 March 2007 (has links)
[pt] Neste trabalho estuda-se, por meio de simulação Monte- Carlo, a importância de duas restrições para a estimação e a previsão do Modelo Vetorial Autoregressivo - VAR, quais sejam: cointegração e características cíclicas comuns, relativas ao longo-prazo e ao curto-prazo, respectivamente. Cabe observar que as restrições cíclicas comuns de curto- prazo consideradas neste trabalho estão na forma fraca (Weak Form - WF), como definido por Hecq, Palma e Urbain (2006). Esta tese tem dois objetivos. O primeiro trata da investigação do desempenho de duas classes de critérios de informação para a seleção dos parâmetros do modelo. O primeiro critério, denotado por IC(p), refere-se ao critério tradicional, enquanto o segundo, denotado por IC (p, s), refere-se ao critério de seleção alternativo como proposto por Vahid e Issler (2002). Quanto aos segundo objetivo, a investigação avalia o desempenho da previsão de três modelos: i) modelo que considera as restrições de cointegração e do tipo WF; ii) modelo que apenas considera as restrições de cointegração e iii) modelo sem restrições. Os resultados indicam que o critério de informação alternativo, IC(p, s), apresenta desempenho superior ao modelo escolhido pelos critérios convencionais IC(p). Em relação ao desempenho da previsão, o modelo que considera as restrições de cointegração e do tipo WF apresenta desempenho predicativo superior. / [en] This paper investigates the importance of two restrictions included in the estimation and the forecasting of the Vectorial Autoregressive - VAR model using simulation Monte- Carlo. Those are the cointegration and the common cyclical characteristics restrictions related to the long run and the short run, respectively. The short run common cyclical restrictions considered in this work are in the Weak Form - WF, as defined by Hecq, Palm and Urbain (2006). This thesis has two main objectives. The first goal deals with performance of two classes of information criteria for the selection of the parameters in the model. The first criterion, denoted by IC(p) refers to the traditional technique, while the second one, denoted by IC(p,s) refers to the alternative selection criterion as proposed by Vahid and Issler (2002). On the concern of the second objective, it evaluates the forecasting accuracy of three models: i) model that considers the cointegration and WF restrictions; ii) model that just considers the cointegration restrictions and iii) model without any restrictions. On balance, the results indicate that the alternative information criterion, IC(p, s), has a better performance than the chosen model using the conventional criteria IC (p). In terms of the forecasting accuracy, the model which considers the cointegration and WF restrictions presents superior predicative performance.

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