The aim of the dissertation is to investigate the dependencies of the structure of polyester multifilament yarn fabrics and their permeability to air on the fabric structure factors and to develop methods for designing air permeable fabrics.

Made available in DSpace on 2015-04-22T22:14:14Z (GMT). No. of bitstreams: 1 Cristina Pessoa Veloso Freire.pdf: 2819799 bytes, checksum: 8919fceb66aefa886139385d2b54aae1 (MD5) Previous issue date: 2010-06-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / the species most frequently at least seven species, has been associated with diseases in humans: Candida albicans, Candida. tropicalis, Candida stellatoidea, Candida pseudotropicalis (now called C. Kefyr), Candida parapsilosis, Candida guilliermondii and Candida krusei. There is an increased occurrence of infections by Candida species, caused by population growth that immunosuppression with high predisposition to develop infections. Also, there was an increased use of antifungal agents, where some Candida showed a decline in sensitivity to these agents. Increasing numbers of fungal strains are becoming resistant to the drugs available. As a result, there is a constant search for new antifungal drugs more effective and safer than existing ones. The naphthoquinones are widely distributed in nature, with the known activities, the antibacterial, antifungal and antitumor. Thus the objective of this study was to evaluate the antifungal activity and cytotoxicity of naphthoquinones semisynthetic in Candida strains isolated from the oral cavity. The strains studied were C. albicans, C. krusei, C. parapsilosis, C. kefyr, C. tropicalis and C. dubliniensis. The susceptibility of semi-synthetic naphthoquinones was tested initially by using the simple diffusion from the hole in the culture medium (hole plate), to obtain a quantitative analysis, and then for a quantitative analysis technique was used in broth. Patterns known antifungals were used, for comparison of antifungal activity. The semi-synthetic naphthoquinone that showed the best antifungal activity in the hole plate technique was NORALFA, followed by IVS322 with average of inhibition zone against C. albicans 21,26 mm and 16,62 mm respectively, and quantitative analysis of antifungal activity, substances NORALFA and IVS322 stood out with MIC against C. albicans 0,125 μg/ml and 0.5 μg/ml. It was found that none of the substances tested at a concentration of 50 μg/ml caused hemolysis and fibroblasts tested remained viable at a concentration of 12,5 μg/ml. This result is favorable, since the hemolysis test is a measure of toxicity and a positive result would preclude the therapeutic use of these substances. Through this work we determine the potential antifungal and cytotoxic profile of the compounds tested. / A candidíase é uma doença infecciosa causada pelo fungo Candida, sendo a espécie albicans a mais freqüentes. Sete espécies pelo menos, tem sido associadas a doenças no homem: Candida albicans, Candida. tropicalis, Candida stellatoidea, Candida peseudotropicalis (hoje chamada de C. Kefyr), Candida parapsilosis, Candida guilliermondii e Candida krusei. Há um aumento da ocorrência das infecções por espécies de Candida, causada pelo crescimento da população com imunodepressão que grande predisposição ao desenvolvimento de infecções.Números cada vez maiores de cepas fúngicas estão se tornando resistentes aos fármacos disponíveis no mercado. Em virtude disso, existe uma constante procura de novos fármacos antifúngicos mais eficazes, e mais seguros que os já existentes. As naftoquinonas são amplamente distribuídas na natureza, tendo como atividades conhecidas, a atividade antibacteriana, antifúngica e antitumoral. Desta forma o objetivo deste estudo foi avaliar a atividade antifúngica e citotoxicidade de naftoquinonas semi-sintéticas em cepas de Candida isoladas da cavidade oral. As cepas estudadas foram de C. albicans, C. krusei, C. parapsilosis, C. kefyr, C. tropicalis e C. dubliniensis. A suscetibilidade das naftoquinonas semisintéticas foi testada inicialmente, através do teste difusão a partir de orifício no meio de cultura (hole plate). Posteriormente para uma analise quantitativa foi utilizada a técnica de microdiluição em caldo. Padrões antifúngicos conhecidos foram usados, para comparação da atividade antifúngica. A citotoxicidade foi avaliada em hemácias de camundongos através do teste de hemólise e através do teste de viabilidade celular em fibroblastos, utilizando o Alamar Blue. A naftoquinona semisintética que apresentou melhor atividade antifúngica na técnica hole plate foi a NORALFA, seguida da IVS322 com médias do halo de inibição frente a C. albicans de 21,26 e 16,62 mm respectivamente, e na análise quantitativa da atividade antifúngica, as substâncias NORALFA e IVS322 se destacaram com CIM frente a C. albicans 0, 125 μg/ml e 0,5 μg/ml. Verificou-se que nenhuma das substâncias testadas a uma concentração de 50 μL/ml provocou hemólise e os fibroblastos testados permaneceram viáveis na concentração de 12,5 μL/ml. Este resultado é favorável, uma vez que o teste de hemólise é um parâmetro de toxicidade e um resultado positivo poderia impossibilitar o uso terapêutico dessas substâncias. Com a realização deste trabalho conseguimos determinar o potencial antifúngico e o perfil citotóxico das substâncias testadas.

Maize is susceptible to biotic and abiotic stresses. The most important abiotic stresses in Africa are drought and low soil fertility. Aflatoxin contamination is a potential problem in areas facing drought and low soil fertility. Three studies were conducted to evaluate maize germplasm for tolerance to stress. In the first study, fifteen maize inbred lines crossed in a diallel were evaluated under drought, low N stress, and well-watered conditions at six locations in three countries to estimate general (GCA) and specific combining ability (SCA), investigate genotype x environment interaction, and estimate genetic diversity and its relationship with grain yield and heterosis. GCA effects were not significant for grain yield across environments. Lines with good GCA effect for grain yield were P501 and CML258 across stresses. Lines CML339, CML341, and SPLC7-F had good GCA effects for anthesis silking interval across stresses. Additive genetic effects were more important for grain yield under drought and well-watered conditions. Heterosis estimates were highest in stress environments. Clustering based on genetic distance calculated using marker data from AFLP, RFLP, and SSRs grouped lines according to origin. Genetic distance was positively correlated with grain yield and specific combining ability. In the second study, synthetic hybrids were evaluated at seven locations in three countries to estimate GCA and SCA effects under low N stress and optimal conditions and investigate genotype x environment interaction. GCA effects were significant for all traits across low N stress and optimal conditions. The highest yielding synthetic hybrids involved synthetics developed from stress tolerant lines. Synthetics 99SADVIA-# and SYNA00F2 had good GCA for grain yield across low N stress conditions. Heterosis was highly correlated with grain yield. Optimal environments explained more variation than stress environments. The third study evaluated the agronomic performance and aflatoxin accumulation of single and three-way cross white maize hybrids at five locations in Texas. Inbreds CML343, Tx601W, and Tx110 showed positive GCA effects for grain yield. Significant GCA effects for reduced aflatoxin concentration were observed in lines CML269, CML270, and CML78 across locations. Differences in performance between single and three-way crosses hybrids were dependent mostly on the inbred lines.

Maize is susceptible to biotic and abiotic stresses. The most important abiotic stresses in Africa are drought and low soil fertility. Aflatoxin contamination is a potential problem in areas facing drought and low soil fertility. Three studies were conducted to evaluate maize germplasm for tolerance to stress. In the first study, fifteen maize inbred lines crossed in a diallel were evaluated under drought, low N stress, and well-watered conditions at six locations in three countries to estimate general (GCA) and specific combining ability (SCA), investigate genotype x environment interaction, and estimate genetic diversity and its relationship with grain yield and heterosis. GCA effects were not significant for grain yield across environments. Lines with good GCA effect for grain yield were P501 and CML258 across stresses. Lines CML339, CML341, and SPLC7-F had good GCA effects for anthesis silking interval across stresses. Additive genetic effects were more important for grain yield under drought and well-watered conditions. Heterosis estimates were highest in stress environments. Clustering based on genetic distance calculated using marker data from AFLP, RFLP, and SSRs grouped lines according to origin. Genetic distance was positively correlated with grain yield and specific combining ability. In the second study, synthetic hybrids were evaluated at seven locations in three countries to estimate GCA and SCA effects under low N stress and optimal conditions and investigate genotype x environment interaction. GCA effects were significant for all traits across low N stress and optimal conditions. The highest yielding synthetic hybrids involved synthetics developed from stress tolerant lines. Synthetics 99SADVIA-# and SYNA00F2 had good GCA for grain yield across low N stress conditions. Heterosis was highly correlated with grain yield. Optimal environments explained more variation than stress environments. The third study evaluated the agronomic performance and aflatoxin accumulation of single and three-way cross white maize hybrids at five locations in Texas. Inbreds CML343, Tx601W, and Tx110 showed positive GCA effects for grain yield. Significant GCA effects for reduced aflatoxin concentration were observed in lines CML269, CML270, and CML78 across locations. Differences in performance between single and three-way crosses hybrids were dependent mostly on the inbred lines.

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