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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.
131

Anomalias dentárias e associações na fissura labiopalatina unilateral / DENTAL ANOMALIES AND ASSOCIATIONS IN FRACTURE UNILATERAL CLEFT

Lopez, Diego Antonio Sigcho 29 November 2013 (has links)
Anomalias dentárias ocorrem com maior frequência em indivíduos com fissura labiopalatina (Slayton et al 2003) e em seus irmãos no afetados quando comparados à população sem fissura (Eerens et al 2001). Estudos realizados em indivíduos sem fissura demonstram que diferentes tipos de anomalias apresentam-se frequentemente associadas entre si (Baccetti 1998, Garib, Peck e Gomez 2009, Garib et al 2010). O objetivo do presente estudo foi determinar associações entre anomalias dentárias em indivíduos com fissura de lábio e palato, considerando que esse conhecimento pode fornecer informações essenciais para a definição de protocolos de tratamento. Metodologia: foram analisadas 500 radiografias panorâmicas de pacientes com fissura completa de lábio e palato unilateral, na faixa etária de 7 a 11 anos, obtidas do arquivo de Radiologia do Hospital de Reabilitação de Anomalias Craniofaciais, da Universidade de São Paulo (HRAC-USP). As radiografias foram avaliadas por um único examinador sobre um negatoscópio para o diagnóstico das anomalias dentárias. Os 30 primeiros registros foram avaliados duas vezes, com intervalo de uma semana para análise da concordância intra-examinador, com valores de Kappa acima de 0,77. As anomalias dentárias dos lados fissurado (LF) e não fissurado (LNF) foram analisadas separadamente. Os dados obtidos foram avaliados por estatística descritiva e comparados pelo Teste de McNemar. Resultados: As anomalias mais frequentemente observadas foram a agenesia (58,4%) e a microdontia (33,6%). O LF apresentou maior prevalência de anomalias dentárias (73%) quando comparado com o LNF (27%). Associações estatisticamente significativas foram observadas entre hipodontia -microdontia (p<0,001), hipodontia - dente supranumerário (p<0,001), hipodontia - transposição (p<0,001) e infraoclusão - erupço ectópica do 1o molar permanente superior (p=0,004). Conclusão: este estudo revelou associações estatisticamente significativas na ocorrência de anomalias dentárias em indivíduos com fissura labiopalatina, sugerindo que sua etiologia pode compartilhar aspectos genéticos e ambientais comuns ou estar diretamente relacionada à falta de massa mesenquimal. / Dental anomalies frequently occur in individuals with cleft lip and palate (Slayton et al 2003) and their unaffected siblings compared to the population without cleft (Eerens et al 2001). Studies in individuals without cleft demonstrate that different types of anomalies are associated with each other (Baccetti 1998, Garib Peck and Gomez, 2009, Garib et al 2010). The aim of this study was to determine associations between dental anomalies in individuals with complete cleft lip and palate, considering that this knowledge can provide essential information for defining treatment protocols. Methods: The study was conducted on 500 panoramic radiographs of patients with unilateral complete cleft lip and palate, aged 7-11 years, obtained from the Radiology files, Hospital for Rehabilitation of Craniofacial Anomalies, University of So Paulo (HRAC - USP). Radiographs were evaluated by a single examiner on a light box for the diagnosis of dental anomalies. The first 30 records were assessed twice, with a one-week interval to analyze the intra-examiner agreement, with Kappa values above 0.77. The dental anomalies were analyzed separately for the cleft side (CS) and non-cleft side (NCS). Data were analyzed by descriptive statistics and compared using McNemar test. Results: The most frequently observed abnormalities were hypodontia (58.4%) and microdontia (33.6%). The CS showed higher prevalence of dental anomalies (73%) compared to the NCS (27%). Statistically significant associations were observed between hypodontia - microdontia (p < 0.001), hypodontia - supernumerary tooth (p < 0.001), hypodontia - transposition (p < 0.001) and infraocclusion - ectopic eruption of the maxillary first permanent molar (p = 0.004). Conclusion: This study revealed significant associations in the occurrence of dental anomalies in individuals with cleft lip and palate, suggesting that its etiology may share common genetic and environmental factors or be directly related to the lack of mesenchymal mass.
132

"Estudo do desenvolvimento dentário de crianças portadoras de HIV através de exame clínico e radiográfico" / Development dental study in HIV-positive children through radiograph and clinical examination

Rita de Cassia Brandão Bertazzoli 16 February 2006 (has links)
Esta pesquisa teve como objetivo verificar se existe relação entre o uso de terapia anti-retroviral por crianças portadoras do Vírus da Imunodeficiência Humana (HIV) contaminadas pela via vertical e a ocorrência de alterações de desenvolvimento da dentição permanente detectáveis radiograficamente. Foram avaliadas 76 crianças com idades entre 4 anos e um mês e 12 anos e 11 meses que foram distribuídas em 2 grupos: (1) 46 crianças portadoras do HIV em uso de terapia anti-retroviral; (2) 30 crianças sem a infecção. As crianças foram submetidas a radiografias panorâmicas para a avaliação dos estágios de calcificação dentária e através de exame clínico foi avaliada a freqüência de erupção dos dentes permanentes em ambos os grupos. Os resultados obtidos não mostraram diferença estatisticamente significativa nos estágios de calcificação (p=0,051) e na freqüência de erupção dos dentes permanentes (p=0,18), indicando que o uso de anti-retrovirais não interfere no desenvolvimento dentário de crianças portadoras do HIV adquirido pela via vertical / This survey was conducted to verify the correlation between the use of antiretroviral therapy and developmental disturbances in the permanent dentition of children vertically infected by the Human Immunodeficiency Virus (HIV). Seventy-six children aged from 4 years to 1 month and 12 years and 11 month were divided in two groups: 1) 46 children HIV-infected and under antiretroviral therapy; 2) 30 uninfected children. A panoramic radiograph for dental development evaluation was obtained from each child, in order to evaluate the dental calcification stages and the frequency of permanent teeth eruption in both groups. The results did not show any significant statistical difference on dental calcification stages (p=0,051) as well as the permanent teeth results of the frequency eruption (p=0,18) between the HIV-infected and the uninfected children, showing that the antiretroviral therapy does not interfere in the dental development of children infected by HIV acquired by vertical transmission
133

Validação de três métodos para estimativa de idade de crianças e adolescentes brasileiros / Validation of three methods for age estimation of Brazilian children and adolescents

Benedicto, Eduardo de Novaes 31 July 2017 (has links)
A estimativa de idade é um importante recurso em Odontologia Legal. Entre as diversas formas de se obter uma estimativa de idade, pesquisadores podem fazê-la por meio da análise do estágio de mineralização dos dentes permanentes. Este tipo de análise, torna possível que uma simples radiografia panorâmica possa fornecer dados relevantes para identificar um indivíduo falecido, por exemplo. Este estudo propõe a validação, análise da acurácia e a construção de fórmulas baseadas nos métodos de Liliequist e Lundberg com a adaptação de Hägg e Matsson (LLH), Haavikko (HKK) e Mornstad et al. (MSW) para a estimativa de idade pelo estágio de mineralização dos dentes permanentes em crianças e adolescentes brasileiros. Para alcançar este resultado, foram selecionadas radiografias panorâmicas de brasileiros em uma amostra contendo 1.009 radiografias (387 do sexo masculino e 622 do sexo feminino) com idade entre 8-15,99 anos. Destas radiografias, foram selecionadas apenas as que cumpriram com todos os requisitos dos critérios de inclusão e exclusão. Após a aplicação das metodologias, os resultados foram inseridos e trabalhados no Programa Excel, Pacote Estatístico STATA 13.0. (StataCorp LP, College Station, Texas, EUA) e MedCalc (Medcalc® Software, Mariakerke, Bélgica) de acordo com as necessidades do estudo. As amostras foram divididas sem distinção quanto ao sexo, com distinção quanto ao sexo, e com distinção quanto ao sexo e idade. A comparação dos métodos foi realizada pela diferença de médias da idade dentária com a idade cronológica (ID-IC). A acurácia foi analisada pela Diferença Absoluta (DA). O teste normalidade de Skewness e Kurtosis foi empregado e, dependendo do resultado, os dados foram submetidos ao Test t de Student, ou ao teste de Wilcoxon, para amostras pareadas. Como resultado das comparações sem qualquer distinção quanto ao sexo, a melhor acurácia foi obtida por LLH (DA = 0,97 e ID-IC = 0,58), HKK (DA = 1,42 e ID-IC = -1,35) e MSW (DA = 2,48 e ID-IC = 3,08). Com distinção quanto ao sexo, os valores para o masculino foram: LLH (DA = 0,91 e ID-IC = -0,45), HKK (DA = 1,80 e ID-IC = -1,75) e MSW (DA = 2,74 e ID-IC = 1,17); e para o feminino LLH (DA = 1,01 e ID-IC = -0,67), HKK (DA = 1,17 e ID-IC = -1,09) e MSW (DA = 2,31 e ID-IC = 0,53). Na comparação com distinção entre sexo e idade houve um predomínio respectivamente da técnica de LLH, seguida de HKK e MSW. As equações de regressão aplicadas na mesma amostra apresentaram em média DA = 0,72 e ID-IC = -0,01. Também, algumas fórmulas de regressão múltipla foram construídas a partir dos dados apresentados para as metodologias de LLH e HKK, exceto para MSW que não forneceu dados suficientes para o software criar equações. Ao final, foi possível concluir que é possível a validação das metodologias apresentadas para a população brasileira e que a metodologia que mais se aproximou da população brasileira foi o método de Liliequist e Lundberg com a adaptação de Hägg e Matsson. / Age estimation is an important resource in Forensic Dentistry. Among several ways to obtain the age estimation, researchers may do it by analyzing the mineralization stage of permanent teeth. This type of analysis allows that a simple panoramic radiograph to provide relevant data to identify a deceased individual, for example. This study proposes the validation, accuracy analysis and construction of formulas based on the methods Liliequist and Lundberg with the adaptation of Hägg and Matsson (LLH), Haavikko (HKK) and Mornstad et al. (MSW) for the estimation of age by the stage of mineralization of permanent teeth in Brazilian children and adolescents. To achieve the results, panoramic radiographs of Brazilians were selected in a sample containing 1009 radiographs (387 males and 622 females) aged 8-15.99 years. Of these radiographs, it was selected only those that fulfilled all the requirements of the inclusion and exclusion criteria. After applying the methodologies, the results were inserted and worked in the Excel Program, Statistical Package STATA 13.0. (StataCorp LP, College Station, Texas, USA) and MedCalc (Medcalc® Software, Mariakerke, Belgium) according to the needs of the study. The samples were divided without splitting sex, with splitting sex and with splitting sex and age. The comparison of methods was performed by the mean differences between dental age and chronological age (DA-CA). Accuracy was analyzed by Absolute Difference (AD). The Skewness e Kurtosis normality test was employed and the Student t test, or the Wilcoxon test, for paired samples was submitted depending on the results. The results of comparisons informed, without any distinction as to sex, the best accuracy was obtained by LLH (AD = 0.97 and DA-CA = 0.58), HKK (AD = 1.42 and DA-CA = -1.35) and MSW (AD = 2.48 and DA-CA = 3.08). With distinction to sex the values for male were: LLH (AD = 0.91 and DA-CA = -0.45), HKK (AD = 1.80 and DA-CA = -1.75) and MSW (AD = 2.74 and DA-CA = 1.17); and for female: LLH (AD = 1.01 and DA-CA = -0.67), HKK (AD = 1.17 and DA-CA = -1.09) and MSW (AD = 2.31 and DA-CA = 0.53). In the comparison with distinction between sex and age, there was a predominance of the LLH technique, followed by HKK and MSW, respectively. The regression equations applied in the same sample presented mean AD = 0.72 and DA-CA = -0.01. In addition, some multiple regression formulae were constructed from the data presented for LLH and HKK methodologies, except for MSW, which did not provide enough data for the software to create equations. At the end, it was possible to conclude that it is possible to validate the methodologies presented in the Brazilian population and the methodology that most approached the Brazilian population was the Liliequist and Lundberg method with the adaptation of Hägg and Matsson.
134

Ngauruhoe inner crater volcanic processes of the 1954-1955 and 1974-1975 eruptions

Krippner, Janine Barbara January 2009 (has links)
Ngauruhoe is an active basaltic andesite to andesite composite cone volcano at the southern end of the Tongariro volcanic complex, and most recently erupted in 1954-55 and 1974-75. These eruptions constructed the inner crater of Ngauruhoe, largely composed of 1954-55 deposits, which are the basis of this study. The inner crater stratigraphy, exposed on the southern wall, is divided into seven lithostratigraphic units (A to G), while the northern stratigraphy is obscured by the inward collapse of the crater rim. The units are, from oldest to youngest: Unit A, (17.5 m thick), a densely agglutinated spatter deposit with sharp clast outlines; Unit B, (11.2 m) a thick scoria lapilli deposit with local agglutination and scattered spatter bombs up to 1 m in length; Unit C, (6.4 m thick) a clastogenic lava deposit with lateral variations in agglutination; and Unit D, (10 m thick) a scoria lapilli with varying local agglutination. The overlying Unit E (15 cm thick) is a fine ash fallout bed that represents the final vulcanian phase of the 1954-55 eruption. Unit F is a series of six lapilli and ash beds that represent the early vulcanian episode of the 1974-75 eruption. The uppermost Unit G (averaging 10 m thick) is a densely agglutinated spatter deposit that represents the later strombolian phase of the 1974-75 eruption. Units A-D juvenile clasts are porphyritic, with phenocrysts of plagioclase, orthopyroxene, clinopyroxene, minor olivine, within a microlitic glassy groundmass. Quartzose and greywacke xenoliths are common in most units, and are derived from the underlying basement. The 1954-55 and 1974-75 eruptions are a product of a short-lived, continental arc medium-K calc-alkaline magma. The magma originated from the mantle, then filtered through the crust, undergoing assimilation and fractionation, and evolving to basaltic andesite and andesite compositions. The magma body stagnated in shallow reservoirs where it underwent further crustal assimilation and fractionation of plagioclase and olivine, and homogenisation through magma mixing. Prior to the 1954-55 eruption a more primitive magma body was incorporated into the melt. The melt homogenised and fed both the 1954-55 and 1974-75 eruptions, with a residence time of at least 20 years. The 1954-55 eruption produced alternating basaltic andesite and andesite strombolian activity and more intense fire fountaining, erupting scoria and spatter that built up the bulk of the inner crater. A period of relative quiescence allowed the formation of a cooled, solid cap rock that resulted in the accumulation of pressure due to volatile exsolution and bubble coalescence. The fracturing of the cap rock then resulted in a vulcanian eruption, depositing a thin layer of fine ash and ballistic blocks. The 1974-75 eruption commenced with the rupturing of the near-solid cap rock from the 1954-55 eruption in an explosive vulcanian blast, the result of decompressional volatile exsolution and bubble coalescence, and possible magma-water interaction. The eruption later changed to strombolian style, producing a clastogenic lava that partially flowed back into the crater.
135

Tree Rings as Sensitive Proxies of Past Climate Change

Grudd, Håkan January 2006 (has links)
In the boreal forests of the Northern Hemisphere, time series of tree-ring width (TRW) and maximum density in the latewood (MXD) are highly correlated to local instrumental summer-temperature data and are thus widely used as proxies in high-resolution climate reconstructions. Hence, much of our present knowledge about climatic variability in the last millennium is based on tree-rings. However, many tree-ring records have a lack of data in the most recent decades, which severely hampers our ability to place the recent temperature increase in a longer-timescale perspective of natural variability. The main objective of this thesis is to update and extend the Torneträsk TRW and MXD records in northern Sweden. Local instrumental climate-data is used to calibrate the new tree-ring records. The results show that TRW is mainly forced by temperature in the early growing season (June/July) while MXD has a wider response window (June – August) and has a higher correlation to temperature. Two reconstructions of summer temperature are made for (i) the last 7,400 years based on TRW, and (ii) the last 1,500 years based on a combination of TRW and MXD. The reconstructions show natural variability on timescales from years to several centuries. The 20th century does not stand out as a notably warm period in the long timescale perspective. A medieval period from AD 900 – 1100 is markedly warmer than the 20th century. The environmental impact from a large explosive volcanic eruption in 1628/1627 BC is analysed in the tree rings of 14C-dated bog pines in south-central Sweden and in absolutely-dated subfossil pines from Torneträsk. The results show evidence of an impact in the southern site at approximately this time but no detectable impact in the North. Subfossil trees of Fitzroya cupressoides in southern Chile were 14C-dated to approx. 50,000 years BP and amalgamated into a 1,229-year TRW chronology. This tree-ring record is the oldest in the world. The variability in this Last-glacial chronology is similar to the variability in present-day living trees of the same species. These results suggest that the growth–forcing mechanisms 50,000 years ago were similar to those at present.
136

A satellite and ash transport model aided approach to assess the radiative impacts of volcanic aerosol in the Arctic

Young, Cindy L. 08 June 2015 (has links)
The Arctic radiation climate is influenced substantially by anthropogenic and natural aerosols. There have been numerous studies devoted to understanding the radiative impacts of anthropogenic aerosols (e.g. those responsible for producing the Arctic haze phenomenon) and natural aerosols (e.g. dust and smoke) on the Arctic environment, but volcanic aerosols have received less attention. Volcanic eruptions occur frequently in the Arctic and have the capacity to be long duration, high intensity events, expelling large amounts of aerosol-sized ash and gases, which form aerosols once in the atmosphere. Additionally, volcanic eruptions deposit ash, which can alter the surface reflectivity, and remain to influence the radiation balance long after the eruptive plume has passed over and dissipated. The goal of this dissertation is to quantify the radiative effects of volcanic aerosols in the Arctic caused by volcanic plumes and deposits onto ice and snow covered surfaces. The shortwave, longwave, and net direct aerosol radiative forcing efficiencies and atmospheric heating/cooling rates caused by volcanic aerosol from the 2009 eruption of Mt. Redoubt were determined by performing radiative transfer modeling constrained by NASA A-Train satellite data. The optical properties of volcanic aerosol were calculated by introducing a compositionally resolved microphysical model developed for both ash and sulfates. Two compositions of volcanic aerosol were considered in order to examine a fresh, ash rich plume and an older, ash poor plume. The results indicate that environmental conditions, such as surface albedo and solar zenith angle, can influence the sign and the magnitude of the radiative forcing at the top of the atmosphere and at the surface. Environmental conditions can also influence the magnitude of the forcing in the aerosol layer. For instance, a fresh, thin plume with a high solar zenith angle over snow cools the surface and warms the top of the atmosphere, but the opposite effect is seen by the same layer over ocean. The layer over snow also warms more than the same plume over seawater. It was found that plume aging can alter the magnitude of the radiative forcing. For example, an aged plume over snow at a high solar zenith angle would warm the top of the atmosphere and layer by less than the fresh plume, while the aged plume cools the surface more. These results were compared with those reported for other aerosols typical to the Arctic environment (smoke from wildfires, Arctic haze, and dust) to demonstrate the importance of volcanic aerosols. It is found that the radiative impacts of volcanic aerosol plumes are comparable to those of other aerosol types, and those compositions rich in volcanic ash can have greater impacts than other aerosol types. Volcanic ash deposited onto ice and snow in the Arctic has the potential to perturb the regional radiation balance by altering the surface reflectivity. The areal extent and loading of ash deposits from the 2009 eruption of Mt. Redoubt were assessed using an Eulerian volcanic ash transport and dispersion model, Fall3D, combined with satellite and deposit observations. Because observations are often limited in remote Arctic regions, we devised a novel method for modeling ash deposit loading fields for the entire eruption based on best-fit parameters of a well-studied eruptive event. The model results were validated against NASA A-train satellite data and field measurements reported by the Alaska Volcano Observatory. Overall, good to moderate agreement was found. A total cumulative deposit area of 3.7 X 10^6 km2 was produced, and loadings ranged from ~7000 ± 3000 gm-2 near the vent to <0.1 ± 0.002 gm-2 on the outskirts of the deposits. Ash loading histories for total deposits showed that fallout ranged from ~5 – 17 hours. The deposit loading results suggest that ash from short duration events can produce regionally significant deposits hundreds of kilometers from the volcano, with the potential of significantly modifying albedo over wide regions of ice and snow covered terrain. The solar broadband albedo change, surface radiative forcing, and snowmelt rates associated with the ash deposited from the 2009 eruption of Mt. Redoubt were calculated using the loadings from Fall3D and the snow, ice, and aerosol radiative models. The optical properties of ash were calculated from Mie theory, based on size information recovered from the Fall3D model. Two sizes of snow were used in order to simulate a young and old snowpack. Deposited ash sizes agree well with field measurements. Only aerosol-sized ashes in deposits were considered for radiative modeling, because larger particles are minor in abundance and confined to areas very close to the vent. The results show concentrations of ash in snow range from ~ 6.9x10^4 – 1x10^8 ppb, with higher values closer to the vent and lowest at the edge of the deposits, and integrated solar albedo reductions of ~ 0 – 59% for new snow and ~ 0 – 85% for old snow. These albedo reductions are much larger than those typical for black carbon, but on the same order of magnitude as those reported for volcanic deposits in Antarctica. The daily mean surface shortwave forcings associated with ash deposits on snow ranged from 0 – 96 Wm-2 from the outmost deposits to the vent. There were no significantly accelerated snowmelts calculated for the outskirts of the deposits. However, for areas of higher ash loadings/concentrations, daily melt rates are significantly higher (~ 220 – 320%) because of volcanic ash deposits.
137

Les aérosols et le transport dans la haute troposphère et la stratosphère tropicale à partir des mesures du lidar spatial CALIPSO

Vernier, Jean-Paul 09 February 2010 (has links) (PDF)
Ce travail de thèse porte sur la description des aérosols stratosphériques et des mécanismes de transport responsables de leur évolution dans le temps à partir des deux premières années d'observations du lidar CALIOP embarqué sur le satellite franco-américain CALIPSO, lancé en mai 2006. Après adaptation des algorithmes de restitution aux faibles signaux de diffusion Mie des aérosols stratosphériques et correction de l'étalonnage rendue nécessaire par la présence d'aérosols dans la gamme d'altitude de l'étalonnage des produits standards, il est montré qu'il est possible d'obtenir des profils moyens zonaux de rapport de diffusion avec une précision de 2%. Après application de ces corrections ainsi que d'un masque de nuages reposant sur la dépolarisation du signal lidar, l'évolution observée des aérosols entre 15 et 40 km d'altitude de juillet 2006 à septembre 2008, conduit aux conclusions suivantes : a) l'approvisionnement souvent ignoré et fréquent de la stratosphère en aérosols par des éruptions volcaniques relativement mineures, d'indice d'explosivité de 3 à 4, se traduisant par des panaches autour de 19-20 km d'altitude, soulevés lentement par la suite par la circulation de Brewer-Dobson pour parvenir un an plus tard à 25 km ; b) le découplage entre la moyenne et la basse stratosphère séparées par une région de vitesse verticale faible ou nulle vers 20 km. En accord avec les idées prévalant sur le sujet, la moyenne stratosphère tropicale apparaît comme le siège d'un soulèvement lent à une vitesse de l'ordre de 300 m/mois, confiné dans le " tropical pipe ", suivi à plus haute altitude d'un échange méridional d'intensité modulée par l'oscillation quasi-biennale. Par contre et en contradiction avec le schéma aujourd'hui accepté de soulèvement lent produit par l'échauffement radiatif de l'air depuis le niveau du sommet des enclumes convectives vers 14 km, la région en dessous de 20 km apparaît être le siège de violentes injections d'air propre, depuis la troposphère et vraisemblablement lessivé dans les nuages, particulièrement intenses à l'équateur durant la saison convective la plus active de l'été austral. Dans la mesure où la TTL, Tropical Transition Layer, est définie comme la région de la stratosphère soumise à l'influence de la troposphère, ces observations suggèrent que son sommet se situe vers 20 km. Une conséquence du mélange avec l'air propre troposphérique est le nettoyage rapide dans cette tranche d'altitude des aérosols volcaniques qui peuvent s'y trouver. Enfin une autre observation inattendue est celle de la présence chaque année de couches aérosols entre 15 et 18 km limitées à l'Afrique de l'Ouest et à l'Asie du Sud durant leur saison respective de mousson, dont il est suggéré qu'il puisse s'agir de fines poussières minérales d'origine désertique.
138

Análise histopatológica e imuno-histoquímica da erupção papular prurítica associada ao vírus da imunodeficiência humana

Tozzi, Brunela Bastos 22 June 2012 (has links)
Made available in DSpace on 2016-12-23T13:56:13Z (GMT). No. of bitstreams: 1 Brunella Bastos Tozzi.pdf: 5530561 bytes, checksum: 4cb5717338550ea3614682134ea4a15f (MD5) Previous issue date: 2012-06-22 / Introduction: Papular pruritic eruption (PPE) is characterized by the presence of pruritic erythematous papules as chronic disease that affects oftenly seropositive patients. The lesions are seen in different stages, preferably in the trunk and extremities, and end with post inflammatory hyperpigmentation and / or scars resulting from scratching. Objectives: To evaluate the hitopathological and immunohistochemical features of the PPE. Methods: The study enrolled HIV-positive patients with clinical diagnosis of PPE carried out at University Hospital Cassiano Antonio Moraes of the Federal University of Espirito Santo in Vitória, ES. Patients were dermatological examinated and skin lesions photographed. Skin biopsies were obtained to evaluate the histopathological and immunohistochemical features. Results: Thirty-nine patients with EPP were biopsied, 17 were women and 22 men, mean age was 40.2 years ranging from 25 to 63 years. Among the histopathological biopsies, 6 patterns were found and these often: 1) dermal perivascular inflammatory infiltrate, 2) inflammatory infiltrate affecting the follicular unit; 3) interstitial inflammatory infiltrate, 4) inflammatory infiltrate in the subcutaneous tissue, 5) inflammatory infiltrate affecting at least one nerve, 6) signal of the scratching in the epidermis. About immunohistochemistry features, Langerhans cells are found in normal amounts in the epidermis and relatively increased in dermal inflammatory infiltrate. There are predominantly CD8 + T lymphocyte and macrophages in the inflammatory infiltrate compared with CD4 + T lymphocytes. No microorganisms were found using the Ziehl-Neelsen staining and Grocott. Conclusions: It was identified six patterns present in biopsy, in order to obtain a set of histopathologic and immunohistochemical to describe and characterize the PPE histopathological diagnosis. The dermal perivascular inflammatory infiltrate is essential for diagnosis, and other tissue alterations are not mandatory that may be present together or separately, at different stages of the skin lesions. / Introdução: A Erupção Papular Prurítica (EPP) é caracterizada pela presença de pápulas eritematosas pruriginosas de evolução crônica que afetam, com frequência, pacientes HIV positivos. As lesões são observadas em diferentes estágios evolutivos, preferencialmente no tronco e extremidades, e evoluem com hiperpigmentação pós inflamatória e/ou cicatrizes decorrentes da coçadura. Objetivos: Descrever as características histopatológicas e imuno-histoquímicas de biópsias de lesões de EPP em pacientes HIV positivos. Metodologia: Foram selecionados pacientes HIV positivos com diagnóstico clínico de EPP atendidos no Hospital Universitário Cassiano Antônio Moraes (HUCAM) da Universidade Federal do Espírito Santo (UFES), em Vitória-ES. Os pacientes foram submetidos a um exame dermatológico criterioso, as lesões fotografadas e biopsiadas para a avaliação histopatológica e imuno-histoquímica. Resultados: Trinta e nove pacientes com EPP foram biopsiados; 17 eram mulheres e 22 homens; a média de idade foi 40,2 anos variando de 25 a 63 anos. Dentre os aspectos histopatológicos nas biópsias, 6 padrões foram encontrados com frequência sendo esses: 1) infiltrado inflamatório perivascular dérmico; 2) infiltrado inflamatório comprometendo a unidade folicular; 3) infiltrado inflamatório intersticial; 4)infiltrado inflamatório no subcutâneo; 5) infiltrado inflamatório comprometendo pelo menos um nervo; 6) sinal da coçadura na epiderme. Na imuno-histoquímica, as células de Langerhans encontram-se em quantidades normais na epiderme e relativamente aumentadas nos infiltrados inflamatórios dérmicos. Há predomínio de linfócitos T CD8+ e macrófagos nesses infiltrados, comparando com os linfócitos T CD4+. Não foram encontrados microorganismos nos exames, tanto utilizando-se a coloração Ziehl-Neelsen, quanto a coloração Grocott. Conclusões: Foram identificadas seis alterações mais frequentes presentes nas biópsias, afim de se obter um conjunto de alterações histopatológicas e imunohistoquímicas que descrevessem e caracterizassem o diagnóstico histopatológico da EPP. O infiltrado inflamatório perivascular dérmico é imprescindível para o diagnóstico, e as demais são alterações teciduais variáveis, que podem estar presentes juntas ou separadas, em estágios diferentes da doença
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Anomalias dentárias e associações na fissura labiopalatina unilateral / DENTAL ANOMALIES AND ASSOCIATIONS IN FRACTURE UNILATERAL CLEFT

Diego Antonio Sigcho Lopez 29 November 2013 (has links)
Anomalias dentárias ocorrem com maior frequência em indivíduos com fissura labiopalatina (Slayton et al 2003) e em seus irmãos no afetados quando comparados à população sem fissura (Eerens et al 2001). Estudos realizados em indivíduos sem fissura demonstram que diferentes tipos de anomalias apresentam-se frequentemente associadas entre si (Baccetti 1998, Garib, Peck e Gomez 2009, Garib et al 2010). O objetivo do presente estudo foi determinar associações entre anomalias dentárias em indivíduos com fissura de lábio e palato, considerando que esse conhecimento pode fornecer informações essenciais para a definição de protocolos de tratamento. Metodologia: foram analisadas 500 radiografias panorâmicas de pacientes com fissura completa de lábio e palato unilateral, na faixa etária de 7 a 11 anos, obtidas do arquivo de Radiologia do Hospital de Reabilitação de Anomalias Craniofaciais, da Universidade de São Paulo (HRAC-USP). As radiografias foram avaliadas por um único examinador sobre um negatoscópio para o diagnóstico das anomalias dentárias. Os 30 primeiros registros foram avaliados duas vezes, com intervalo de uma semana para análise da concordância intra-examinador, com valores de Kappa acima de 0,77. As anomalias dentárias dos lados fissurado (LF) e não fissurado (LNF) foram analisadas separadamente. Os dados obtidos foram avaliados por estatística descritiva e comparados pelo Teste de McNemar. Resultados: As anomalias mais frequentemente observadas foram a agenesia (58,4%) e a microdontia (33,6%). O LF apresentou maior prevalência de anomalias dentárias (73%) quando comparado com o LNF (27%). Associações estatisticamente significativas foram observadas entre hipodontia -microdontia (p<0,001), hipodontia - dente supranumerário (p<0,001), hipodontia - transposição (p<0,001) e infraoclusão - erupço ectópica do 1o molar permanente superior (p=0,004). Conclusão: este estudo revelou associações estatisticamente significativas na ocorrência de anomalias dentárias em indivíduos com fissura labiopalatina, sugerindo que sua etiologia pode compartilhar aspectos genéticos e ambientais comuns ou estar diretamente relacionada à falta de massa mesenquimal. / Dental anomalies frequently occur in individuals with cleft lip and palate (Slayton et al 2003) and their unaffected siblings compared to the population without cleft (Eerens et al 2001). Studies in individuals without cleft demonstrate that different types of anomalies are associated with each other (Baccetti 1998, Garib Peck and Gomez, 2009, Garib et al 2010). The aim of this study was to determine associations between dental anomalies in individuals with complete cleft lip and palate, considering that this knowledge can provide essential information for defining treatment protocols. Methods: The study was conducted on 500 panoramic radiographs of patients with unilateral complete cleft lip and palate, aged 7-11 years, obtained from the Radiology files, Hospital for Rehabilitation of Craniofacial Anomalies, University of So Paulo (HRAC - USP). Radiographs were evaluated by a single examiner on a light box for the diagnosis of dental anomalies. The first 30 records were assessed twice, with a one-week interval to analyze the intra-examiner agreement, with Kappa values above 0.77. The dental anomalies were analyzed separately for the cleft side (CS) and non-cleft side (NCS). Data were analyzed by descriptive statistics and compared using McNemar test. Results: The most frequently observed abnormalities were hypodontia (58.4%) and microdontia (33.6%). The CS showed higher prevalence of dental anomalies (73%) compared to the NCS (27%). Statistically significant associations were observed between hypodontia - microdontia (p < 0.001), hypodontia - supernumerary tooth (p < 0.001), hypodontia - transposition (p < 0.001) and infraocclusion - ectopic eruption of the maxillary first permanent molar (p = 0.004). Conclusion: This study revealed significant associations in the occurrence of dental anomalies in individuals with cleft lip and palate, suggesting that its etiology may share common genetic and environmental factors or be directly related to the lack of mesenchymal mass.
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Volatilernas påverkan på marina vulkanutbrott / The Impact of Volatiles on Submarine Eruptions

Khadhem, Laith January 2017 (has links)
The Cape Verde archipelago is located 2000 km east of the Atlantic oceanic ridge and 500 km west of the western part of Africa. The plateau of the archipelago rises on average 2 km above the seafloor, which makes it one of the highest oceanic plateaus on Earth. Cape Verde originates from hotspot formation, a geological phenomenon which takes place beyond the tectonic plate boundaries where magma rises to the surface. In this thesis, volcanic material taken from the Charles Darwin volcanic field at a depth of more than 3000 meter and made up by four basaltic rocks and one agglomerate will be investigated. The agglomerate and vesicles in the rock shows that explosive volcanism occurs in high water depths, which is generally not common. Therefore, the material will be investigated to find out how explosive volcanism can occur at high water depths. The investigation will be based on quantifying the number of vesicles to able to calculate their area and analyze the magmatic water content in clinopyroxene crystals taken from the agglomerate by FTIR spectroscopy. Water is a volatile substance in the composition of magma and has a huge effect on its behavior at eruption. The results of quantification show that the area taken by vesicles varies from 7- 54 % which shows that magmatic products with high number of vesicles are common. The FTIR analysis shows that the magmatic water content can be high enough to cause an oversaturated magma system, which creates explosive eruptions. This statement is based on only one clinopyroxene crystal that had a magmatic water content of 3,87 ± 0,77 %. Other possible reasons for explosive eruptions at high water depth are the CO2 content in the magma and the size of volcanic vent. / Kap Verde är en arkipelag, situerad cirka 2000 km öster om den mittatlantiska spridningsryggen och 500 km väster om det afrikanska fastlandet. Arkipelagens platå har en genomsnittlig höjd på 2 km, vilket gör den till en av världens högsta oceaniska platåer. Arkipelagen har uppkommit av hetfläcksbildning, ett geologiskt fenomen baserad på att magma erupteras till ytan där jordskorpan är förtunnad och inte har någon anknytning till de tektoniska plattgränserna. Det som undersöks i detta kandidatarbete är vulkaniskt material, taget från den vulkaniska undervattensön Charles Darwin vulkanfält som ligger i den västra del Kap Verdes norra ö-grupp på över 3000 meterdjup. Materialet består av ett agglomerat och fyra stenstuffer av basaltisk komposition. Agglomeratet tyder på att explosiva vulkanutbrott förekommer, vilket även bekräftas av stenstufferna som har rikligt förekomst av luftbubblor. Explosiva vulkanutbrott är generellt inte förekomliga vid höga vattendjup, därav undersöks materialet för att kunna reda ut orsakerna som ger upphov till förekomsten av explosiva vulkanutbrott. Undersökningen baseras på att kvantifiera luftbubblor hos stenstufferna för att kunna räkna ut arean som upptas och analysera vattenhalten i klinopyroxenkristaller i agglomeratet med hjälp av FTIR spektroskopi. Vatten tillhör de flyktiga beståndsdelar i magmas sammansättning som kallas för volatiler och utgör en viktig parameter för magmans uppträdande vid eruption. Resultatet kvantifiering av luftbubblor visar att arean som upptas av luftbubblor varierar mellan 7–54 % av stenstufferna total area, vilket understryker att magmatiska produkter med hög andel luftbubblor är förkomliga. FTIR analysen visar att det finns tillräckliga höga vattenhalter för ett övermättat magmasystem som ger upphov till vulkanutbrott med explosiva förlopp, baserat på vattenhalten 3,87 ± 0,77 % av en klinopyroxenkristall. Andra möjliga orsaker till uppkomsten av magmatiska produkter med hög andel luftbubblor är koldioxidhalten i magman och storleken på vulkanrören.

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