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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.
101

Compostos ativos de folhas de Eugenia uniflora e seus efeitos contra mofo branco causado por Sclerotinia sclerotiorum em plantas de feijoeiro

Marques, Jacqueline Santos 29 September 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-05-19T11:06:39Z No. of bitstreams: 2 Dissertação - Jacqueline Santos Marques - 2014.pdf: 4633133 bytes, checksum: 8058e7f850a7ea713f7c77b0ad35cc32 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-05-19T11:08:30Z (GMT) No. of bitstreams: 2 Dissertação - Jacqueline Santos Marques - 2014.pdf: 4633133 bytes, checksum: 8058e7f850a7ea713f7c77b0ad35cc32 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-05-19T11:08:30Z (GMT). No. of bitstreams: 2 Dissertação - Jacqueline Santos Marques - 2014.pdf: 4633133 bytes, checksum: 8058e7f850a7ea713f7c77b0ad35cc32 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-09-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The extracts and essential oils from plants are bioactive molecules of interest to resistance induction in plants and the control of plant pathogens. The aim this study was to evaluate the effect of the ethanol extract and essential oil from leaves of Eugenia uniflora and two commercial flavonoid fractions, quercetin and rutin, as bioactive compounds for the control of white mold, caused by the fungus Sclerotinia sclerotiorum in common bean (Phaseolus vulgaris L.). The compounds were tested against pathogen through the mycelial growth, cell viability, sclerotia formation, cell morphology and biochemical aspects. And on the pathossystem Phaseolus vulgaris-Sclerotinia sclerotiorum was evaluated biochemical and molecular aspects (RT-qPCR) involved in the mechanism of plant defense, into a kinetic treatment and infection (12, 24 e 48 hours). The data show that the tested compounds were significantly relevant (P<0.01) to growth inhibition pathogen’s mycelium and cell viability in vitro and in the formation of sclerotia of the pathogen a positive correlation between percent inhibition and the concentration of active compounds applied was observed. The minimum inhibitory concentration (MIC) for S. sclerotiorum was 0.6% (v/v) ethanol extract of leaves from E. uniflora and the 100 ppm of the essential oil. In Bioassays in plants, the treatment with ethanol extract or essential oil from Eugenia uniflora and rutin inhibited the formation of necrotic area in common bean leaves 48 hours after inoculation. Biochemical analysis showed that the compounds induced 12 hours after treatment the activation of key proteins related to plant defense, chitinases, β-1,3- glucanase, phenylalanine ammonia lyase, peroxidases and polyphenoloxidases. Molecular analysis showed that treatment with ethanolic extract, quercetin and rutin in healthy plants activated pathogenesis-related genes (PRs) at different times into the kinetic treatment, and that these genes are highly expressed in plants infected compared to the pretreated and infected plants. The results of this research suggest that the effects of the ethanol extract, flavonoids and oil from Eugenia uniflora are potential bioactive molecules to reduce the severity of disease white mold in bean leaves. / Os extratos e óleos essenciais de plantas são moléculas bioativas de grande interesse para a indução de resistência em plantas e no controle de fitopatógenos. O objetivo deste trabalho foi avaliar o efeito do extrato etanólico e óleo essencial de folhas de E. uniflora e duas frações flavonoides comerciais, quercetina e rutina como compostos bioativos para o controle de mofo branco, causado pelo fungo Sclerotinia sclerotiorum, em feijoeiro comum (Phaseolus vulgaris L.). Os compostos foram testados sobre patógeno através do crescimento micelial, viabilidade celular, esclerogênese, morfologia celular e aspectos bioquímicos. E sobre o patossistema Phaseolus vulgaris-Sclerotinia sclerotiorum foi avaliado aspectos bioquímicos e moleculares (RT-qPCR) envolvidos no mecanismo de defesa da planta, dentro de uma cinética de tratamento e infecção (12, 24 e 48 horas). Os dados mostram que os compostos testados foram significantemente (P<0.01) relevantes na inibição do desenvolvimento e viabilidade celular in vitro do micélio e na formação de escleródios do patógeno, sendo observada uma correlação positiva entre percentual de inibição e as concentrações dos compostos avaliadas. A concentração inibitória mínima (MIC) para o S. sclerotiorum foi de 0.6% (v/v) do extrato etanólico de folhas de E. uniflora e de 100 ppm do óleo essencial. Nos bioensaios em plantas, o tratamento com extrato etanólico ou óleo essencial de folhas de Eugenia uniflora e rutina inibiram a formação de necrose em folhas de feijoeiro comum com 48 horas ápos inoculação. A análise bioquímica mostrou que os compostos induzem com 12 horas após tratamento a ativação das principais proteínas relacionadas à defesa da planta, quitinases, β-1,3- glucanase, fenilalanina amônia-liase, peroxidases, e polifenoloxidases. A análise molecular mostrou que o tratamento com extrato etanólico, quercetina e rutina em plantas sadias ativaram genes relacionados à patogênese (PRs) em diferentes tempos dentro da cinética de tratamento, e que tais genes são altamente expressos em plantas infectadas em comparação as plantas pré tratadas e infectadas. Os resultados obtidos neste trabalho indicam que o extrato etanólico, flavonoides e o óleo essencial de folhas de Eugenia uniflora são moléculas bioativas potenciais para reduzir a severidade da doença mofo branco em plantas de feijoeiro comum.
102

Desenvolvimento de molde de material cerâmico para aplicação em moldagem por injeção de materiais poliméricos

Heiderich, Danilo Carvalho 15 October 2014 (has links)
Made available in DSpace on 2016-03-15T19:36:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-10-15 / Universidade Presbiteriana Mackenzie / The need for speed increasing production, reducing weight and price of the product and the need for creation of complex parts made the use of polymeric materials, increasingly feasible in relation to other materials. The implementation of polymeric materials in various areas of production ensure the continued development of techniques for forming the same, with advances in technology also creates the need to increase the speed of transition between the development stages of a project as well as reducing the costs involved to achieve project deadlines and keep it commercially competitive. In view of the mechanical properties of ceramic material and its ease of forming was objective the creation of a plastic injection mold made of ceramic material. For this we performed a brief study of the main means of forming polymer and a study on the properties of ceramic and polymeric materials. Was later developed the part to be injected, and from the same, the ceramic mold that is used. After scaling the same calculations were made to adapt the project to verify its viability and the process of analysis by finite elements. These results show that the injection pressure and the necessary clamping force are below the maximum forces, supported by ceramic material, which demonstrates the viability of the ceramic mold, as an alternative to traditional metal molds. / A necessidade de velocidades de produção cada vez maiores, redução de pesos e preço do produto e a necessidade da criação de peças complexas tornaram o uso de materiais poliméricos, cada vez mais viável em relação aos demais materiais. A implementação dos materiais poliméricos nas mais diversas áreas de produção implica no desenvolvimento contínuo das técnicas de conformação dos mesmos, porém com os avanços tecnológicos cria-se também a necessidade de aumentar a velocidade de transição entre as etapas de desenvolvimento de um projeto bem como a redução dos custos envolvidos no processo a fim de atingir os prazos do projeto e mantê-lo comercialmente competitivo. Tendo em vista as propriedades mecânicas do material cerâmico bem como sua facilidade de conformação objetivou-se a criação de um molde para injeção de plásticos feito de material cerâmico. Para isso foi realizado um breve estudo sobre os principais meio de conformação de polímeros também um estudo sobre as propriedades dos materiais cerâmicos e poliméricos. Posteriormente foi desenvolvida a peça a ser injetada e, a partir da mesma, o molde cerâmico que será utilizado. Após o dimensionamento do mesmo foram realizados os cálculos de adequação do projeto para verificar a sua viabilidade bem como a análise pelo processo de elementos finitos. Os resultados deste estudo mostram que as pressões de injeção bem como a força de fechamento necessária são inferiores às forças máximas, suportadas pelo material cerâmico, o que demonstra a viabilidade da criação do molde cerâmico, como alternativa aos moldes metálicos tradicionais.
103

Sclerotinia sclerotiorum em sementes de soja: sobrevivência, efeito na germinação, tamanho de amostra para análise e eficiência in vitro de fungicidas / Sclerotinia sclerotiorum in soybean seeds: survival, effect on germination, sample size for analysis and in vitro efficiency of fungicides

Meyriele Pires de Camargo 27 January 2014 (has links)
O fungo Sclerotinia sclerotiorum, agente causal do mofo branco, encontra-se disseminado em todo o país e afeta mais de 400 espécies de plantas, dentre elas a cultura da soja, causando danos consideráveis no rendimento. A transmissão do patógeno ocorre por meio de sementes contendo micélio dormente ou pela presença de escleródios no lote, os quais podem permanecer viáveis por um longo período, dificultando o manejo da doença. Este trabalho teve como objetivos verificar a viabilidade do patógeno em sementes durante o armazenamento e seu efeito sobre o poder germinativo; comparar tamanhos de amostras de sementes visando à detecção do fungo; e avaliar a sensibilidade in vitro de S. sclerotiorum a fungicidas. Para avaliação da sobrevivência do patógeno, sementes de soja foram inoculadas, artificialmente, com três isolados de S. sclerotiorum, e armazenadas em duas condições, câmara fria e seca (20 ºC e 45% UR) e ambiente não controlado, durante oito meses. A cada dois meses foram realizados testes de sanidade pelo meio de cultura ágar-bromofenol (Neon), utilizando-se 4 repetições de 100 sementes, e testes de germinação, com 4 repetições de 50 sementes, pelo método do rolo de papel. No experimento de amostragem foram avaliadas dez amostras de sementes de soja pelo método do meio Neon, comparando-se quatro tamanhos de amostra: 400, 800, 1600 e 2400 sementes. Para avaliação da sensibilidade in vitro de S. sclerotiorum a fungicidas, foram utilizados 13 ingredientes ativos, em 7 doses e 5 repetições. Os valores da concentração inibitória de 50% (CI50) e 100% (CI100) foram estimados com base na percentagem de inibição do crescimento micelial. Além disso, realizaram-se a quantificação e pesagem dos escleródios formados após 15 dias de incubação. A presença do patógeno S. sclerotiorum, afetou negativamente a germinação das sementes, com redução média de 32% em relação à testemunha. Verificou-se diferença entre os isolados com relação à agressividade. O patógeno sobreviveu nas sementes em ambos os ambientes de armazenamento, porém, em ambiente controlado a redução na geminação das sementes foi de 14% e na incidência do fungo de 16%, enquanto que, em laboratório, esta redução foi de 23% na germinação e de 62% na incidência. Não houve diferença estatística com relação à quantidade de sementes amostradas na detecção de S. sclerotiorum, entretanto, constatou-se maior frequência de ocorrência do patógeno à medida que o número de sementes amostrado foi maior. Todos os fungicidas foram capazes de reduzir o crescimento micelial de S. sclerotiorum, bem como a produção de escleródios, sendo que os ingredientes ativos piraclostrobina, carbendazim, tiabendazol e tiofanato metílico, além de apresentarem CI50 inferior a 1 mg L-1, também inibiram totalmente a formação de escleródios em concentrações inferiores a 5 mg L-1. / The fungus Sclerotinia sclerotiorum, the causal agent of white mold is spread throughout the country and affects more than 400 species of plants, including soybean, causing considerable decrease in yield. The pathogen transmission occurs through seeds with dormant mycelium or by the presence of sclerotia in the lot, which can remain viable for a longer period, making hard the disease management. This study aimed to verify the viability of the pathogen in seeds during the storage period and its effect on germinative power; compare sizes of seed samples to determine the presence of the fungus; and to evaluate the in vitro sensibility of S. sclerotiorum to fungicides. To determine the pathogen survival, soybean seeds were inoculated artificially with three isolates of S. sclerotiorum, and stored into two conditions, cold and dry chamber (20 °C and 45% RU) and in uncontrolled environment, for eight months. Every two months health tests were performed by culture media bromophenol agar (Neon), using 4 repetition of 100 seeds, and germination tests, with 4 repetition of 50 seeds, by the method of the paper roll. During the experiment of sampling, ten samples of soybean seeds were evaluated by the method of media Neon, comparing four sample sizes: 400, 800, 1600 and 2400 seeds. To evaluate the in vitro sensibility of S. Sclerotinia to fungicides were used 13 active ingredients, in 7 doses and 5 repetitions. The values of the 50% inhibitory concentration (IC50) and 100% (IC100) were estimated based on the percentage inhibition of the mycelial growth. In addition, it was performed the quantification and weighing of sclerotia formed after 15 days of incubation. The pathogen S. sclerotiorum in soybean seeds affected negatively the germination of seeds, with an average reduction of 32% compared to the control. There was difference between the isolates in relation to aggressiveness. The pathogen survived in seeds in both storage environments, however, under controlled environment, the decrease in the germination of the seeds was 14% and in its incidence was 16%, while in laboratory this reduction was 23% in the germination and 62% in the incidence. There was no statistical difference in the quantity of seeds sampled in the detection of S. sclerotiorum, however, a higher frequency of pathogen occurrence was verified as the number of sampled seeds was enlarged. All fungicides were able to reduce the mycelial growth of S. sclerotiorum and sclerotia production, and the active ingredients pyraclostrobin, carbendazim, thiabendazole and thiophanate methyl, besides having IC50 of less than 1 mg L-1 also completely inhibited the formation of sclerotia in concentrations less than 5 mg L-1.
104

Caracterização de fungos intestinais cultiváveis e avaliação da estrutura da micobiota intestinal humana de indivíduos obesos, com sobrepeso e eutróficos

Borges, Francis Moreira 03 May 2018 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2018-05-17T15:27:41Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-05-22T11:42:00Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2018-05-22T11:42:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-05-03 / Os fungos têm um papel complexo no trato intestinal, influenciando diretamente na saúde e na doença e sua disbiose pode contribuir para a obesidade. O objetivo deste estudo foi avaliar a diversidade de fungos da microbiota intestinal humana entre indivíduos eutróficos, com sobrepeso e obesos. Foram coletados espécimes fecais de 72 indivíduos adultos e análises dependentes e independentes de cultivo foram realizadas para avaliar os fungos presentes. As leveduras foram identificadas pela técnica de ionização e dessorção a laser assistida por matriz acoplada a analisador do tipo espectro de massa por tempo de vôo (MALDI-TOF MS) e os fungos filamentosos por microcultivo. A contagem média de fungos filamentosos e leveduras cultiváveis foi de 1,58 Log10 UFC/g de fezes. Diferenças significativas no nível populacional dos fungos filamentosos foi observado entre os grupos dos indivíduos eutróficos e obesos. Trinta e quatro gêneros de fungos foram identificados. O filo predominante foi Ascomycota com 29 gêneros e/ou espécies diferentes, seguido por Zigomycota e Basidiomycota. O fungo mais isolado nos indivíduos eutróficos foi Paecylomyces sp. e nos indivíduos obesos Penicillium sp. Os indivíduos eutróficos apresentam uma diversidade ligeiramente maior de fungos filamentosos do que os indivíduos obesos. Os indivíduos do sexo feminino tiveram um maior número de fungos diferentes quando comparados aos do sexo masculino. A análise de eletroforese em gel de gradiente desnaturante (DGGE) mostrou agrupamento dos indivíduos eutróficos e com sobrepeso em um cluster e dos indivíduos obesos em outro cluster distinto, embora a riqueza tenha sido baixa nos três grupos. A análise de hibridização in situ florescente (FISH) demonstrou maior densidade relativa de C. albicans no grupo obeso quando comparado ao eutrófico e pela análise de reação da polimerase em cadeia quantitativa (qPCR) um número maior de cópias de DNA de fungos e do filo Ascomycota nos indivíduos obesos quando comparado aos indivíduos com sobrepeso e obesos. Foi verificada correlação positiva entre os fungos e os parâmetros antropométricos colesterol total, LDL, triglicerídeos, hemoglobina, HOMA-IR, HOMA-β, insulina, glicose sérica, creatinina e porcentagem de fibras e carboidratos da dieta. Outros estudos são necessários para melhor compreender a interrelação entre a micobiota do intestino e a obesidade. Futuramente, este conhecimento poderá ser utilizado na modulação da micobiota intestinal e no tratamento da obesidade. / Fungi have a complex role in the intestinal tract, directly influencing health and disease and potential dysbiosis could contribute to obesity. The aim of this study was to investigate the fungal diversity of human gut microbiota among eutrophic, overweight, and obese individuals and to understand the gut microbial ecology shifts between healthy and obese individuals. Stool samples of 72 adult individuals were collected and dependent and independent cultive approach were performed to evaluate the fungi. The yeasts were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and the filamentous fungi were identified by microculture. The mean count of filamentous fungi and yeast was 1.58 log10 CFU/g of feces. Significant differences in the population level of the filamentous fungi was observed within eutrophic and obese groups. Overall, 34 genera were identified. The predominant phylum was Ascomycota with 20 different genera, followed by Basidiomycota and Zygomycota. The most prevalent specie was Paecylomyces sp. in euthrophic individuals and Penicillium sp. in obese individuals. The results of the eutrophic individuals suggest a slightly higher diversity of fungi within these individuals. Female individuals had a greater diversity of fungal types compared to males. The denaturing gradient gel electrophoresis (DGGE) analysis showed the grouping of eutrophic and overweight individuals in one cluster and of obese individuals in another cluster, although richness was low in all three groups. The fluorescence in situ hybridization (FISH) analysis showed a higher relative density of C. albicans in the obese group when compared to eutrophic and by the quantitative real time PCR (qPCR) a larger number of DNA copies of fungi and the phylum Ascomycota in obese individuals when compared to overweight and obese individuals. There was a positive correlation between fungi and the anthropometric parameters, total cholesterol, LDL, triglycerides, hemoglobin, HOMA-IR, HOMA-β, insulin, serum glucose, creatinine and percentage of dietary fibers and carbohydrates. Other studies are needed to better understand the causal relationship between gut mycobiota and obesity. This knowledge could be used in modulating the gut mycobiota and identifying future obesity treatments.
105

Influence of Environmental Parameters on Mold Sampling Results

Fishman, Benjamin 16 June 2017 (has links)
Mold is a type of fungus present in nearly all environments. Mold thrives under several environmental parameters such as high humidity and an adequate food source. A professional, such as an industrial hygienist, can measure mold in indoor and outdoor environments. Industrial hygienists commonly use a cascade impactor with a culture plate to capture air within a sampling area. While collecting air samples, environmental parameters such as temperature, humidity, and carbon dioxide are recorded. A laboratory then cultures and analyzes the samples, identifying the types and amounts of viable mold found in the sampling area. In this study, a data analysis method is used to interpret lab results and compare those results to the environmental parameters measured during collection. The study aims to show the relationship between the environmental parameters (temperature, humidity, carbon dioxide) and the types and amounts of mold that were measured in both indoor built environments and their surrounding outdoor areas. Among all 170 different sampling locations, the outdoor areas had higher counts and concentrations of mold. In addition, both indoor and outdoor areas saw Penicillium, Aspergillus, and Cladosporium as the most prevalent molds, with Cladosporium having the highest counts. Lower temperatures and humidity had a very small influence on mold growth and thus, yielded the lowest counts. Furthermore, the highest concentrations of mold were found within the same temperature and humidity ranges for both indoor and outdoor environments.
106

Návrh technologie výroby šnekového soukolí z plastu / Technology design manufacturing plastic worm gear

Petrucha, Roman January 2017 (has links)
The master thesis deals with the design of the injection mold for the production of a plastic two-part worm which is part of the worm gear set in the sleeve. From the beginning, an analysis of the assigned component was performed, specifying its function and specifying the criteria that must be met by the component. In addition, design of the production technology (injection molding) was carried out, followed by theoretical analysis of plastic materials, injection molding technology and mold design. Subsequently, in the practical part, a complete design of the injection mold was made on the basis of simulations and technological calculations. On the basis of the parameters of the injection mold, a machine was chosen, on which production should be carried out according to the proposed technological procedure. The conclusion of the thesis contains a technical and economic evaluation of the proposed technology for the production of Plastics splatter component.
107

Optimalizace vakuového odvzdušnění vstřikovací formy / Optimization of the vacuum deaeration of the injection mold

Rohlínková, Marie January 2018 (has links)
The project elaborated design of optimization venting of molds exhibiting bubbles or low quality weld lines. Based on a literature study of the injection mold venting, the use of vacuum venting, namely the VACUUMJET system of the Spanish CUMSA manufacturer, has been proposed. The experiments proved the elimination of bubbles in the part and the marked improvement of visual quality of the weld lines. The effect on the closing force was not confirmed. The use of the system is more economical for larger batches production, or when high quality parts are required that allow price increasing.
108

Obrábění vulkanizačních forem z hliníkových slitin / Machining of vulcanizing molds from aluminum alloys

Kaška, Zdeněk January 2020 (has links)
This diploma thesis is focused on the issue of deep drilling of vulcanization molds from various aluminum alloys. The work will describe a brief description of machined materials and tools for deep drilling, including the production of the vulcanization mold itself. Based on experimental measurements, the analysis of data and knowledge gained from deep drilling of aluminum alloys with different silicon contents will be performed. In the end, the individual components of force loads for both machined materials will be compared
109

Návrh technologie výroby vstřikovací formy pro přesné lití / Design of injection mold production technology for precision casting

Fendrich, Tomáš January 2020 (has links)
The diploma thesis deals with the design and production of an aluminum injection mold for investment casting. The work briefly describes the technology of investment casting together with a description of the types of molds, their internal arrangement and the most commonly used materials. Another part of the work is devoted to the analysis of aluminum molds machining. Emphasis was placed mainly on those operations, that will be used in production of mold. The practical part describes in detail the process of designing the model and mold, as well as the process of designing production technology. The construction is performed using the program SolidWorks, production technology using the program SolidCam. At the end of the work, the mold is assembled and the functionality of the mold is verified by means of test injection and economic evaluation is made.
110

Technologie výroby plastového krytu zásuvky / Production technology for plastic socket outlet

Pokorný, Martin January 2009 (has links)
This project concentrates on the technology of manufacturing of the plastic socket outlet. It consists of two parts, where the first part is a literature study. Here are described the characteristics of the materials and their specifications. Further on is described basic knowledges technical methods of injection and some other technologies. The second section consists of the right proposal of the material. Further on in this section is described technological treatment. Mechanical function and its design and technical drawing are a part of this second section. As a final result is a brief comparison of the technology between the injection or pressing into molds. Herewith is also included a simplified financial budget calculation.

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