O aumento de demanda por combustíveis menos poluentes e de fontes renováveis faz com que o Etanol se destaque como uma alternativa as fontes convencionais de energia. O crescente aumento no consumo deste produto, para os próximos anos, exigirá meios de transporte e estocagem eficientes e seguros, desde os diversos produtores até os terminais de distribuição. O transporte por dutos é, sem dúvida, a forma mais econômica de transporte deste produto, porém, há evidências de que esses dutos de transporte e fundo de tanques de armazenamento de etanol poderiam ser susceptíveis ao fenômeno de corrosão sob tensão. Este fenômeno pode ser avaliado, por exemplo, por ensaios de baixa taxa de deformação (BTD) com corpos de prova com ou sem entalhe. Este trabalho tem por objetivo avaliar a influência da severidade do entalhe em corpos de prova ensaiados a baixa taxa de deformação no meio etanol combustível simulado (PRCI SFGE). Foram preparados quatro tipos de corpos de prova de aço API X70: sem entalhe, com entalhe da norma NACE TM 0111, com entalhe “intermediário” (severidade 18,9% menor que o da norma) e com entalhe “menos severo” (redução de 37,2% na severidade do entalhe, segundo concentração de tensões, quando comparado com o da norma). Os resultados mostram que os quatro tipos de corpos de prova apresentaram susceptibilidade ao meio (etanol PRCI SFGE). Nos corpos de prova sem entalhe esta susceptibilidade foi evidenciada somente nas imagens fractográficas. Já nos CPs com entalhe, mesmo com redução de concentrações de tensões no entalhe, observou-se resultados bem semelhantes, ficando evidenciada a susceptibilidade ao meio tanto nas imagens fractográficas (fratura frágil), quanto pela diminuição da ductilidade. / The increasing demand for cleaner fuels and renewable sources makes the ethanol rise as an alternative to conventional energy sources. The increasing consumption rate of this product, predicted for the upcoming years, will require safer and more efficient methods for transportation and storage through the entire transport cycle. Pipelines are the most economical way to transport it. However, there is evidence that pipeline transportation and the bottom of the storage tanks for ethanol might be susceptible to the stress corrosion cracking phenomenon. This phenomenon can be assessed by slow strain rate tests (SSRT) using smooth or notched specimen. This work aims to evaluate the influence of notch severity in specimens submitted to SSRT technique in simulated fuelgrade ethanol (PRCI SFGE). Four types of specimens of steel API X70 were prepared: unnotched, notched according to standard NACE TM 0111, notched with “intermediate” severity (severity 18.9% lower than the standard) and “less severe” notched (reduction of 37.2% on severity of the notched when compared with the standard). The results show that both sample types presented susceptibility in the solution (ethanol PRCI SFGE). For the unnotched specimens this susceptibility was observed only in fractographic images. In the notched specimens, despite the reduction of stress concentrations in the notch, the results were very similar. In this case the susceptibility can be observed in fractographic images (brittle fracture) as well as by decrease in the ductility.

O aumento de demanda por combustíveis menos poluentes e de fontes renováveis faz com que o Etanol se destaque como uma alternativa as fontes convencionais de energia. O crescente aumento no consumo deste produto, para os próximos anos, exigirá meios de transporte e estocagem eficientes e seguros, desde os diversos produtores até os terminais de distribuição. O transporte por dutos é, sem dúvida, a forma mais econômica de transporte deste produto, porém, há evidências de que esses dutos de transporte e fundo de tanques de armazenamento de etanol poderiam ser susceptíveis ao fenômeno de corrosão sob tensão. Este fenômeno pode ser avaliado, por exemplo, por ensaios de baixa taxa de deformação (BTD) com corpos de prova com ou sem entalhe. Este trabalho tem por objetivo avaliar a influência da severidade do entalhe em corpos de prova ensaiados a baixa taxa de deformação no meio etanol combustível simulado (PRCI SFGE). Foram preparados quatro tipos de corpos de prova de aço API X70: sem entalhe, com entalhe da norma NACE TM 0111, com entalhe “intermediário” (severidade 18,9% menor que o da norma) e com entalhe “menos severo” (redução de 37,2% na severidade do entalhe, segundo concentração de tensões, quando comparado com o da norma). Os resultados mostram que os quatro tipos de corpos de prova apresentaram susceptibilidade ao meio (etanol PRCI SFGE). Nos corpos de prova sem entalhe esta susceptibilidade foi evidenciada somente nas imagens fractográficas. Já nos CPs com entalhe, mesmo com redução de concentrações de tensões no entalhe, observou-se resultados bem semelhantes, ficando evidenciada a susceptibilidade ao meio tanto nas imagens fractográficas (fratura frágil), quanto pela diminuição da ductilidade. / The increasing demand for cleaner fuels and renewable sources makes the ethanol rise as an alternative to conventional energy sources. The increasing consumption rate of this product, predicted for the upcoming years, will require safer and more efficient methods for transportation and storage through the entire transport cycle. Pipelines are the most economical way to transport it. However, there is evidence that pipeline transportation and the bottom of the storage tanks for ethanol might be susceptible to the stress corrosion cracking phenomenon. This phenomenon can be assessed by slow strain rate tests (SSRT) using smooth or notched specimen. This work aims to evaluate the influence of notch severity in specimens submitted to SSRT technique in simulated fuelgrade ethanol (PRCI SFGE). Four types of specimens of steel API X70 were prepared: unnotched, notched according to standard NACE TM 0111, notched with “intermediate” severity (severity 18.9% lower than the standard) and “less severe” notched (reduction of 37.2% on severity of the notched when compared with the standard). The results show that both sample types presented susceptibility in the solution (ethanol PRCI SFGE). For the unnotched specimens this susceptibility was observed only in fractographic images. In the notched specimens, despite the reduction of stress concentrations in the notch, the results were very similar. In this case the susceptibility can be observed in fractographic images (brittle fracture) as well as by decrease in the ductility.

Orientador: João Aristeu da Rosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-16T17:55:39Z (GMT). No. of bitstreams: 1 Ribeiro_AlineRimoldi_M.pdf: 8854165 bytes, checksum: dfc09fd67f41d32a061c2b77ca9455b8 (MD5) Previous issue date: 2010 / Resumo : A doenca de Chagas, assim como seu agente etiologico Trypanosoma cruzi, foram descritos por Carlos Ribeiro Justiniano das Chagas. T. cruzi e transmitido por hemipteros sendo os generos Panstrongylus, Rhodnius e Triatoma os mais importantes. Com resultados bastante satisfatorios em relacao ao controle do principal vetor, T. infestans, outros triatomineos de importancia secundaria, coletados no peridomicilio, passaram a assumir maior relevancia, dentre essas especies, T. sordida. As populacoes de T. cruzi apresentam grande variabilidade intraespecifica evidenciada por diferencas na morfologia, na virulencia e patogenicidade, na habilidade de evasao a resposta imune do hospedeiro e na constituicao antigenica. Essa diversidade pode estar associada a sua adaptacao e sobrevivencia em diferentes hospedeiros. As diferentes formas de manifestacao clinica da doenca no homem podem ser associadas com cepas especificas ou com marcadores geneticos do hospedeiro, embora ambos possam influenciar o curso da infeccao. Este trabalho objetivou a caracterizacao biologica, morfologica e molecular de tres cepas de T. cruzi (SI5, SI8 e SIGR3) isoladas de T. sordida coletadas em Santo Inacio, Bahia. Desse modo, o estudo biologico indicou que as cepas isoladas de Santo Inacio, pertencem ao Biodema III e Zimodema I. Os resultados das mensuracoes das cepas SI5, SI8 e SIGR3 mostraram polimorfismo das formas tripomastigotas sanguineas, embora com predominancia de formas intermediarias para largura do corpo e curtas para comprimento total do corpo no decurso da infeccao experimental. Foram avaliados para as formas epimastigotas, parametros como comprimento total do corpo, largura e indice nuclear e observamos para as cepas SI5, SI8 e SIGR3 respectivamente, formas intermediaria/intermediaria/baixo, curto/intermediario/baixo e curta/larga/baixo para os parametros descritos acima. O significado geral desse polimorfismo ainda nao foi suficientemente investigado, desconhecendo-se se ele expressa um diferente comportamento biologico das cepas ou se reflete apenas a existencia de um "complexo" morfologico. A caracterizacao molecular das cepas SI5, SI8 e SIGR3, as enquadram no grupo II, o que indica, que nesse local circula uma mesma linhagem de T. cruzi, apesar das mesmas terem sido isoladas de hospedeiros e epocas distintas. / Abstract: Chagas disease and its causative agent Trypanosoma cruzi were described by Carlos Ribeiro Justiniano das Chagas. T. cruzi is transmitted by blood-sucking hemipterous and Panstrongylus, Rhodnius and Triatoma are the most important genera. Satisfactory results were achieved to the control of the main vector, T. infestans. However, other bugs of secondary importance, like Triatoma sordida collected around the houses began to assume greater epidemiological importance. The populations of T. cruzi show great variability among individuals demonstrated by differences in morphology, virulence and pathogenicity, ability to evade the host immune response and antigenic constitution. Such diversity may be associated with their adaptation and survival in different hosts. The course of the infection in human may be associated with specific strains or host genetic markers, although both can influence. This aim of this study was the biological, morphological and molecular characterization of three strains of T. cruzi (SI5, and SI8 SIGR3) isolated from T. sordida collected in Santo Inacio, Bahia. The biological study indicated that the isolates from Santo Inacio, belong to Biodeme III Zimodeme I. The results of measurements of the strains SI5, SI8 SIGR3 showed polymorphism of blood trypomastigotes, with a predominance of intermediate forms to body width and short length for total body in the course of experimental infection. Parameters such as: total body length, width and nuclear index were evaluated for epimastigotes, and observed for strains SI5, SI8 and SIGR3 respectively, forms na intermediate / middle / low, short / intermediate / low, short / wide / low for the parameters described above. The general meaning of this polymorphism has not been sufficiently investigated. It is not known if such poliymorphism expresses a different biologic behavior of the strains or merely is a result of a "complex" morphology. According to the molecular characterization the strains SI5, SI8 SIGR3 are in group II, which indicates that in this site it occurs the same lineage of T. cruzi, despite their different sources (isolated from different hosts and different times). / Mestrado / Parasitologia / Mestre em Parasitologia

Made available in DSpace on 2014-10-09T12:55:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:05Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste trabalho foram determinadas as concentrações elementares de Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb e Zn por meio da análise por ativação com nêutrons instrumental (INAA) em 204 fragmentos cerâmicos arqueológicos Marajoara, dos quais, 156 foram cedidos pelo Museu de Arqueologia e Etnologia da USP (MAE) e 48 cedidos pela Profª Denise Pahl Schaan, curadora do Museu do Marajó, além de 9 cerâmicas contemporâneas produzidas e comercializadas na Ilha do Marajó. Realizaram-se análises por espectroscopia de ressonância paramagnétca eletrônica (EPR) em 8 amostras arqueológicas e 1 amostra contemporânea para identificar a temperatura de queima e análises de difratometria de raio-X (XRD) em 13 amostras arqueológicas e 2 amostras contemporâneas para o estudo da composição mineralógica. O estudo das amostras discrepantes foi realizado por meio da distância Mahalanobis e o efeito do tempero adicionado à pasta cerâmica por meio do filtro modificado Mahalanobis. Os resultados foram interpretados utilizando-se a análise de conglomerados, análise de componentes principais e análise discriminante. A análise Procrustes, utilizada para o estudo de seleção de variáveis, mostrou que as variáveis Ce, Fe, Eu, Hf, K e Th são suficientes para caracterizar as amostras analisadas. O estudo comparativo entre as amostras arqueológicas e contemporâneas apresentou a formação de dois grupos bem definidos e próximos para as cerâmicas arqueológicas, e a formação de um terceiro grupo distante para as amostras contemporâneas, indicando que as amostras arqueológicas são bem diferentes das amostras contemporâneas. Tanto as análises de EPR, quanto de XRD, não apresentaram fatores relevantes para a diferenciação entre as amostras arqueológicas e contemporâneas. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:06/58555-4

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-29T11:04:55Z No. of bitstreams: 1 brunoeduardopereira.pdf: 1461941 bytes, checksum: 91aae0fd48e25bdc7d9b2092a649b994 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-07T21:49:24Z (GMT) No. of bitstreams: 1 brunoeduardopereira.pdf: 1461941 bytes, checksum: 91aae0fd48e25bdc7d9b2092a649b994 (MD5) / Made available in DSpace on 2017-08-07T21:49:24Z (GMT). No. of bitstreams: 1 brunoeduardopereira.pdf: 1461941 bytes, checksum: 91aae0fd48e25bdc7d9b2092a649b994 (MD5) Previous issue date: 2015-06-17 / A alta acurácia da core biopsy (CB) em diagnosticar câncer em lesões mamárias já é amplamente comprovada. Porém, o número necessário de fragmentos que deve ser obtido para alcançar este objetivo, em lesões BIRADS® 4 e 5, ainda não está estabelecido. Objetivo: Avaliar quantos fragmentos são necessários, em CB guiada por ultrassom (US) de lesões suspeitas de câncer BI-RADS® 4 (B4) e 5(B5), para o diagnóstico de malignidade. Método: Foram selecionadas 59 pacientes consecutivas, com 66 lesões mamárias maiores ou iguais a 1 cm, classificadas em B4 ou B5, e, posteriormente, encaminhadas ao Serviço de Mastologia do Hospital Universitário da Universidade Federal de Juiz de Fora para realização de CB guiada por US. As biópsias foram realizadas por 01 operador, utilizando aparelho de ultrassom com sonda linear de 10 MHz e 01 modelo de pistola de biópsia automática, com agulhas de 14 gauge (GA) e excursão de 12 ou 22 mm. Um total de 5 disparos foram realizados em cada lesão. A cada disparo, o fragmento retirado foi colocado em um frasco exclusivo, recebendo a identificação de acordo com a ordem dos disparos e analisado histopatologicamente. Todos os fragmentos provenientes dos disparos foram incluídos no estudo, mesmo aqueles que obtiveram pouco tecido ou aqueles que não atingiram a lesão. Os resultados anatomopatológicos (AP) das CB foram classificados em benignos ou malignos. Os classificados como malignos correspondiam àqueles com diagnóstico de carcinoma in situ ou invasivo. Os demais foram classificadas como benignos. Os AP das CB foram comparados com os resultados da parafina proveniente de exérese cirúrgica ou com a estabilidade no follow up das lesões. Resultados: A média de idade das pacientes é de 52,6 (± 13,9) anos. CB com diagnóstico de malignidade foi encontrado em 59,4% e de benignidade em 40,6% das biópsias realizadas. Em relação à classificação das lesões, de acordo com o BI-RADS®, 43 (67,2%) lesões foram classificadas como B4 e 21 (32,8%) como B5. O tempo médio de follow up para as 8 pacientes que não realizaram exérese cirúrgica foi de 19,13 meses. Houve 100% de concordância entre o resultado AP do 1º fragmento com o AP da biópsia cirúrgica ou com o follow up das lesões benignas que foram acompanhadas. Conclusão: A retirada de 1 fragmento foi suficiente para o correto diagnóstico de malignidade e benignidade em CB guiadas por US de lesões classificadas como B4 ou B5 com tamanho igual ou superior a 1 cm. / Core biopsy (CB) is widely attested to provide high accuracy for the detection of breast cancer in breast lesions. However, the number of specimens that are required to achieve this in Breast Imaging-Reporting and Data System (BIRADS®) 4 and 5 lesions is yet to be determined. Objective: To evaluate the number of specimens required to diagnose malignancy when using ultrasound (US)-guided CB for BI-RADS® 4 (B4) and 5 (B5) suspected breast cancer lesions. Methods: We selected 59 consecutive patients who were referred to the Mastology Service of the University Hospital of the Federal University of Juiz de Fora for US-guided CB. These patients had 66 breast lesions that measured 1 cm or larger and were classified as B4 or B5. A single operator performed the biopsies, using an ultrasound device with a 10-MHz linear probe, 1 automatic biopsy gun model, 14-gauge needles and 12- or 22-mm excursion. A total of 5 cores were taken from each lesion. The fragment obtained from each biopsy was placed in a separate vial, identified according to the order in which it was taken, and submitted to histopathologic analysis. All the fragments obtained from the biopsies were included in this study, even those that provided small amounts of tissue or resulted from biopsies that had missed the lesion. The CB specimen’s anatomopathological findings were classified as benign or malignant. The CB specimens classified as malignant had a corresponding diagnosis of in situ or invasive carcinoma. The remaining CB specimens were classified as benign. The CB specimens’ anatomopathological findings were compared to those obtained from surgically resected and paraffinised specimens or the lesion’s stability during follow-up consultations. Results: The average patient age was 52.6 (± 13.9) years. Malignancy was diagnosed in 59.4% of the CB specimens, and 40.6% were classified as benign. Regarding the BI-RADS® classifications of the lesions, 43 (67.2%) lesions were classified as B4 and 21 (32.8%) were classified as B5. The average duration of follow-up for the 8 patients who did not undergo surgical resection was 19.13 months. There was 100% agreement between the anatomopathological findings from the first fragment and the anatomopathological findings from the surgical biopsy or the follow-up of the benign lesions. Conclusion: A biopsy of 1 fragment was sufficient for the correct diagnosis of malignant and or benign status in USguided CBs of lesions that were classified as B4 or B5 and measured 1 cm or larger.

Orientador: Antonia Cecilia Zacagnini Amaral / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T01:09:52Z (GMT). No. of bitstreams: 1 Quast_MonicaPaiva_D.pdf: 2160555 bytes, checksum: a8f9e004b6d58d12222f57e63c865d89 (MD5) Previous issue date: 2013 / Resumo: Espécies são unidades fundamentais da biologia e sua identificação é essencial para a pesquisa nos mais diversos campos. Esta tarefa, no entanto, é dificultada por limites interespecíficos naturalmente mal definidos, especialmente em ambientes marinhos, onde complexos de espécies crípticas são comuns. Assim, a delimitação de espécies tem recebido grande atenção nos últimos anos e técnicas moleculares têm se mostrado de grande importância para a questão. Corbula (Bivalvia: Corbulidae) é um gênero frequente e ecologicamente importante em comunidades bentônicas marinhas de sublitoral. A taxonomia do grupo é bastante confusa, em parte devido à plasticidade fenotípica das conchas que dificulta o estabelecimento de limites morfológicos entre as espécies. O presente estudo teve como objetivo estudar, com base em sequências de dois marcadores moleculares (COI e 16S), os limites entre seis espécies de Corbula morfologicamente identificadas da costa sudeste e sul do Brasil, de forma a testar a delimitação morfológica. Como se trata de espécies predominantemente de sublitoral, o material analisado encontrava-se preservado em álcool, havendo sido fixado em formol. Dessa forma, fez-se necessário o desenvolvimento de protocolos específicos de extração e amplificação. Uma combinação de extração orgânica com adsorção em sílica mostrou-se o melhor método de extração de DNA total. Para as reações de amplificação, a utilização de nested PCR produziu resultados superiores à PCR direta. As análises de delimitação utilizaram quatro métodos diferentes, dois baseados em árvores (GMYC e Brownie) e dois não (regra das 4x e ABGD). Os resultados divergiram entre métodos e marcadores, mas a combinação das diferentes linhas de evidência permitiu corroborar a delimitação morfológica de três espécies (Corbula caribaea, Corbula tryoni e Corbula lyoni). Os indivíduos identificados como Corbula patagonica dividiram-se em duas espécies distintas. O único indivíduo de Corbula aequivalvis foi considerado distinto das outras espécies e um indivíduo atribuído a Corbula sp1 não pôde ser distinguido de C. caribaea / Abstract: Species are fundamental unities in many biological studies and, being so, their identification is essential for researches in many different fields. This task, however, is complicated by badly defined interspecies boundaries, especially in the sea, where cryptic species are quite common. Species delimitation has been receiving much attention, and molecular techniques have been proved of great value to the matter. Corbula (Bivalvia, Corbulidae) is frequent and ecologically important genus in benthic marine communities. Nevertheless, its taxonomy is confusing, in part due to a plastic shell, which makes it difficult to establish species boundaries. This study aimed to analyze the COI and 16S sequences of six morphologically identified Corbula species occurring off the South-Southeastern Brazilian coast. Being a mainly sublittoral genus, most of the analyzed material had been previously sampled, fixed in formalin and preserved in alcohol. Hence, initially specific protocols for DNA extraction and PCR were developed. Better results were obtained with an extraction protocol combining organic extraction and silica adsorption. The nested PCR yielded more product than the direct PCR. Delimitation analyses were conducted with four different methods: two tree based (GMYC and Brownie) and two non-tree based (4x rule and ABGD). Different methods and markers produced different delimitations, but the combined evidence supports the morphological delimitation of three species: Corbula caribaea, Corbula tryoni and Corbula lyoni. Individuals assigned to Corbula patagonica were separated into two molecular species. Only one individual of Corbula aequivalvis was analyzed and it was distinguished from other species. One individual assigned to Corbula sp1 could not be distinguish from C. caribaea / Doutorado / Ecologia / Doutora em Ecologia

Dans le cadre de cette étude, l'influence du confinement de la plasticité en pointe de fissure sur la ténacité mesurée du matériau a été abordée. Après une étude de la microstructure du matériau, une étude expérimentale approfondie de son comportement mécanique a été mise en oeuvre. Un modèle complexe combinant un écrouissage anisotrope avec un endommagement lui aussi anisotrope comprenant une prise en compte de l'éffet de géométrie par le paramètre de Lode a été mis en place. L'ensemble des travaux se termine par une étude d'un cas concret de gazoduc entaillé soumis à une pression interne jusqu'à éclatement duquel on peut conclure que l'éprouvette de type SENT est plus adaptée que les autres pour l'étude du comportement de structures tubulaires minces. / In this thesis the influence of plastic constraint at a crack tip on the mesured tough-ness of a material has been evaluated. After a study of the microstructure of the material, an ex-perimental study of its mechanical behaviour was made. A complex model combining an anisotrope hardening with an anisotrope damage law including a geometry contridution by means of the Lode parameter was then used. The porject ends with a study of the bursting test of a precracked line pipe. We can conclude from this test that the SENT specimen is more suitable for the study of thin tubes.

Human adenoviruses (HAdVs) are non-enveloped DNA viruses, currently comprising 52 serotypes which are divided into seven species, designated A to G. The HAdVs are associated with a number of diseases affecting respiratory, urinary, gastrointestinal tracts and the eye. Human AdVs have increasingly been recognized as important pathogens in immunocompromised individuals. Human AdVs are ubiquitous in the environment resulting in the possible contamination of treated and untreated drinking water supplies by human secretions and excretions. As AdVs do not have an envelope, they are extremely resistant to inactivation, allowing for prolonged survival in the environment. The presence of AdVs in water sources is considered important, as they are exceptionally resistant to selected water treatment processes. Precise typing of HAdVs is, therefore, essential for epidemiological surveillance and the understanding of infection chains. The aim of this study was to determine the prevalence and genetic heterogeneity of HAdVs circulating in communities in selected regions of Africa compared to the rest of the world. It is also important to determine the genetic relationship between HAdVs strains occurring in water sources and those detected in human clinical specimens, as this may give some indication as to whether or not water sources are a potential source of infection. As part of ongoing surveillance in southern Africa of treated and untreated water sources for enteric viruses, 765 water samples were tested using a nested polymerase chain reaction (nPCR) for HAdVs. Of these samples, 65 (8.6%) water samples were positive for HAdVs, and selected samples were characterised. In the untreated water, HAdV-F was the dominant species (65.6%) and HAdV-D was second-most common (21.9%) species identified. Species HAdV–B, -A and –C were identified amongst the rest of the strains. From treated water, HAdV-D and –F were identified in one isolate each. Analysis of diarrhoeal stool specimens for HAdVs identified HAdV-F as the predominant species, comprising 77.8% of the identified strains, with species HAdV-C and –A less common, identified in 11.1% specimens. In the respiratory specimens from the same region, HAdV-C was identified in 28.6% of the specimens. Comparative genetic analysis of HAdVs from water sources and clinical specimens showed genetic relatedness between the strains. Water may therefore play an important role as source of infection in the surrounding communities. In developing countries, diarrhoea is a major cause of morbidity and mortality and after rotaviruses HAdVs are considered to be the second-most important cause of viral infantile diarrhoea. Samples also were available from Kenya, where there are very little data on the prevalence and distribution of HAdV serotypes associated with diarrhoea in paediatric patients. From Kenya, 278 stool specimens were analysed, of which 104 (43 diarrhoea; 61 non-diarrhoea) were from an urban hospice for human immunodefiency virus (HIV)-seropositive children, 94 from selected urban clinics and 80 from the rural setting. From these, the detection of HAdVs in diarrhoeal and non-diarrhoeal stool specimens was 43.3% and 16.4%, respectively. In the urban hospice setting, 43.3% of the stool specimens from HIV-seropositive children tested positive for HAdV. The overall detection of HAdVs species and genotypes in the stool specimens showed HAdV-D to predominate, being detected in 36.1% of specimens with HAdV-C (29.5%), HAdV-F (16.4%), HAdV-B (13.1%), and HAdV-A (6.5%) present in lower numbers. This study provided valuable new data on the prevalence and distribution of HAdV genotypes in diarrhoeal stool specimens in Africa. In this study where nucleotide sequence comparison was used to determine the genetic relatedness of African HAdVs to those from the rest of the world, it was noted that in most cases the African strains differed from those from the rest of the world. The use of molecular techniques for the detection and characterisation of HAdVs, especially in Kenyan cohorts, was of importance, as it provided new baseline data for further burden of disease studies which are necessary for future prevention and treatment programmes. / Dissertation (MSc)--University of Pretoria, 2010. / Medical Virology / unrestricted

There is limited scientific knowledge on the composition of human odor from different biological specimens and the effect that physiological and psychological health conditions could have on them. There is currently no direct comparison of the volatile organic compounds (VOCs) emanating from different biological specimens collected from healthy individuals as well as individuals with certain diagnosed medical conditions. Therefore the question of matching VOCs present in human odor across various biological samples and across health statuses remains unanswered. The main purpose of this study was to use analytical instrumental methods to compare the VOCs from different biological specimens from the same individual and to compare the populations evaluated in this project. The goals of this study were to utilize headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC/MS) to evaluate its potential for profiling VOCs from specimens collected using standard forensic and medical methods over three different populations: healthy group with no diagnosed medical or psychological condition, one group with diagnosed type 2 diabetes, and one group with diagnosed major depressive disorder. The pre-treatment methods of collection materials developed for the study allowed for the removal of targeted VOCs from the sampling kits prior to sampling, extraction and analysis. Optimized SPME-GC/MS conditions has been demonstrated to be capable of sampling, identifying and differentiating the VOCs present in the five biological specimens collected from different subjects and yielded excellent detection limits for the VOCs from buccal swab, breath, blood, and urine with average limits of detection of 8.3 ng. Visual, Spearman rank correlation, and PCA comparisons of the most abundant and frequent VOCs from each specimen demonstrated that each specimen has characteristic VOCs that allow them to be differentiated for both healthy and diseased individuals. Preliminary comparisons of VOC profiles of healthy individuals, patients with type 2 diabetes, and patients with major depressive disorder revealed compounds that could be used as potential biomarkers to differentiate between healthy and diseased individuals. Finally, a human biological specimen compound database has been created compiling the volatile compounds present in the emanations of human hand odor, oral fluids, breath, blood, and urine.

Bio-composites are increasing in demand due to governmental incentives across the globe for both environmental and human health reasons. The ideal bio-composite is renewable, recyclable, available, and non-toxic. To properly engineer bio-composite products, the physical properties of the fiber as well as fiber/matrix interactions must be known. The problem lies in the fact that many suitable natural fibers are not currently available in a material form that may be easily worked with. This research investigates methods to process raw kenaf (hibiscus cannabinus) on a scale that allows researchers to make more consistent samples for testing. Though kenaf is highlighted, these processing methods may be applied to any natural fiber. The raw fibers are processed into kenaf chopped strand mats (KCSM) by adapting basic paper-making techniques. KCSM exhibit paper-like qualities and mechanical properties and provide a material of uniform thickness for use in composite parts. Also presented are a basic understanding of natural fiber constituents and effects of mechanical and co-mechanical treatments on those constituents. To test KCSM, samples are made for the ASTM D3039 tensile testing and for testing in a dynamic material analyzer (DMA). Both mechanically and chemo-mechanically processed samples are made for the purpose of comparison. Also, I-beam bridges are built with KCSM to demonstrate how KCSM may be used to create a structure. This is spurred on by the annual SAMPE bridge competition that includes special categories for natural fiber beams. The lay-up procedure is shown in detail to provide a framework that future competitors may use to build quality I-beams for this competition. The properties obtained by using the KCSM are competitive with other reported properties for kenaf-based composites. A kenaf I-beam demonstrates a strength-to-weight ratio that is 65% of a berglass I-beam built to the same dimensions. Trade-os of using KCSM are the random 2d-fiber orientation and brittle failure, which are not usually desirable in composite components. The chemically treated samples indicate a higher degree of crystallinity but demonstrate inferior mechanical properties when compared to the untreated samples.