• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 32
  • 26
  • 6
  • 4
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 94
  • 34
  • 10
  • 10
  • 9
  • 8
  • 7
  • 7
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 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.
71

Characterization and identification of microbial communities in pigeon droppings using Culture-Independent techniques

Leareng, Samuel Keeng 08 1900 (has links)
M. Tech. (Department of Biotechnology, Faculty of Applied and Computer Science), Vaal University of Technology| / Pigeon droppings, found in abundance in most cities and towns where pigeons are found, are a source of potential yeast and molds into the environment. Invasive fungal infections are a cause of morbidity and often mortality in immunocompromised individuals. The objective of this study was to the identification of bacterial and mold agents from pigeon droppings. Pigeon droppings samples were collected from three locations during the winter and summer months and studied for the occurrence of bacteria, yeast and molds by utilising culture-independent techniques. Amplification of the 16S rDNA gene and the internal transcribed spacer (ITS) region, cloning and ARDRA and DGGE were used for the characterisation of the microbial populations followed by sequencing. Several mold and yeasts, as well as bacteria were found to be present in pigeon droppings, which can spread into the environment and be transmitted to immunocompromised individuals and children. DGGE analysis of the bacterial communities revealed banding patterns that clustered all but one winter samples and all summer samples, showing a high similarity among the microbial members in both seasons and sample locations. Fungal DGGE analysis revealed clusters that grouped summer and winter samples from Johannesburg and Pretoria while VUT samples were clustered on their own. From the identification of fungal and bacterial DNA, Cryptococcus species was the majority of fungi isolated from the dropping samples. Geotrichum, Kazachstania and Fusarium species were isolated from phylotypes obtained from ITS amplicons analysed by ARDRA. Lactobacillus and Enteroccoccus species, organisms usually found in the gastrointestinal tract were the common bacterial members identified. The results showed no difference in microbial communities across all sample locations, while seasonal changes also had no impact in microbial community patterns.
72

Estudo comparativo entre duas técnicas para montagem do modelo de gesso de arcadas superiores em articulador semi-ajustável / A comparative study between two techniques to mount the maxillary cast in semi-adjustable articulator

Costa, Rogério Ribas da 20 November 2001 (has links)
Este estudo avaliou a habilidade de duas técnicas, uma convencional e uma de transferência direta do molde, para a montagem do modelo de gesso maxilar no articulador. Um único paciente do sexo feminino, 39 anos, portador de arcada superior de Classe I de Kennedy (desdentado posterior bilateral) foi usado para esta investigação. Foram obtidos 20 modelos de gesso em cada técnica, totalizando 40 montagens nos articuladores. Com o modelo maxilar montado, cada articulador foi fotografado do mesmo lado direito da radiografia em norma lateral da paciente, obtida com o arco facial montado em sua face. As medidas analisadas nos traçados realizados sobre as fotografias e na radiografia, foram obtidas calculando-se o ângulo entre a interseção do plano oclusal da maxila e o plano de referência horizontal (plano de Frankfurt), representado pelo arco facial na radiografia da paciente, comparando-o com o ângulo entre o plano oclusal do modelo de gesso e o ramo superior do articulador em ambas as técnicas, por meio do software UTHSCSA Image Tool. O dados foram submetidos à análise estatística. Os resultados deste estudo demonstraram uma capacidade maior de reprodução daquele ângulo quando uma técnica de transferência direta do molde é usada. Da mesma maneira, foi verificado uma distorção significante na reprodutibilidade dos modelos montados pela técnica convencional. / This study assessed the ability of two techniques to mount the maxillary cast in the articulator, a conventional technique and one of direct transfer of the maxillary arch impression from the patient\'s mouth to the articulator. A single female subject, 39 years old, with a partially edentulous arch, Kennedy´s Class I, was used in this investigation. It was obtained 20 casts in each technique, totaling 40 cast mountings in the articulators. With the maxillary cast mounted, each articulator was photographed in the same right side of the lateral skull cephalometric radiograph of the patient with the face-bow mounted in her face. The measures obtained by the photographic and cephalometric tracings were evaluated by calculating the angle made by the intersection of the maxillary occlusal plane with craniofacial horizontal reference plane (Frankfort´s plane) on the patient´s cephalogram and comparing it with the angle between the occlusal plane of the cast with the upper member of the articulators in both techniques using the UTHSCSA Image Tool computerized program. The measuring data was submitted to the statistical analysis. The results of this study demonstrated a better capacity of reproduction of that angle when a direct transfer technique is used. In the same way, it was found a significant low level of reproducibility in mounting the maxillary cast when a conventional technique is used.
73

Fontes de vantagem competitiva em situaçăo de oligopsônio: um estudo no segmento de moldes e estampos

Barbosa, Ricardo de Abreu 08 September 2011 (has links)
Made available in DSpace on 2016-03-15T19:25:41Z (GMT). No. of bitstreams: 1 Ricardo de Abreu Barbosa.pdf: 1308703 bytes, checksum: b46940cc592ab2b1c37c8963f1cd5438 (MD5) Previous issue date: 2011-09-08 / Fundo Mackenzie de Pesquisa / This dissertation investigated the sources of competitive advantage of Brazilian firms manufacturing molds and dies which, despite the performance in the context of market oligopsony, had highlighted the creation and appropriation of value based on the development of resources and capabilities within their firms. It was proceeded a review of the concepts of competitive advantage, economic value, the resource-based view and market oligopsony. The method employed was a qualitative, exploratory and descriptive approach, which involved the preparation of semi-structured indepth interviews, transcription and content analysis technique according to Bardin (1977). As a previous step to doing research, it was interviewed four top executives of the major automobile companies established in the country aimed at understanding the competitiveness of the automotive market and its effects on the segment of molds and dies, as well as an indication of the prominent national firms considered segment toolmaker. Further, we interviewed the leaders of the six companies indicated by automobile in order to draw them to focus on the perception that they were addressed, the resources responsible for the differentiation and management of such resources in order to work in a market oligopsony typical supply chain of the automotive industry. As a result, it was observed that the leading companies were those that aligned its resources to the competitive goals of the automotive sector, guided by the quest to reduce costs and time in developing projects for new vehicles. The resources identified as determinants of competitive advantage of these companies were: (a) the technological infrastructure, (b) the team of professionals and (c) the direct action of the owners. Capabilities were cited as resulting from: (a) knowledge in the process of forming (for printing), (a) the ability to setup and upgrade the technological infrastructure, and (c) the management of key people in the organization. The involvement of oligopsony market was not important for differentiation in value creation, but to the appropriation of value created by these companies, which spawned the development of new capabilities: (a) ability to exploit the benefits of seasonal demand, (b) emphasis on the economic and financial management, and (c) policy of reinvesting company's financial results. It was discussed the paradigm of comparison for determining the extent of the competitive advantage of these companies, in view of the internationalization of competition in the segment, and it was identified that the appropriation of value is a function of value creation, as a condition for sustainable enterprises that are in a position of competitive advantage. / Esta dissertação investigou as fontes de vantagem competitiva de firmas brasileiras de fabricação de moldes e estampos que, não obstante a atuação em contexto de mercado de oligopsônio, apresentaram destaque na criação e apropriação de valor com base no desenvolvimento de recursos e capacidades no interior de suas firmas. Procedeu-se a revisão dos conceitos de vantagem competitiva, de valor econômico, da visão baseada em recursos e do mercado de oligopsônio. O método empregado seguiu uma abordagem qualitativa, exploratória e descritiva, o que envolveu a preparação de roteiro semi-estruturado, realização de entrevistas em profundidade, transcrição e análise do conteúdo segundo a técnica de Bardin (1977). Como etapa precedente à realização da pesquisa, foram entrevistados quatro altos executivos das principais empresas automobilísticas instaladas no país visando a compreensão da competitividade no mercado automobilístico e dos seus efeitos sobre o segmento de moldes e estampos, bem como a indicação das firmas nacionais consideradas destacadas no segmento ferramenteiro. Na sequência, foram entrevistados os dirigentes das seis empresas indicadas pelas automobilísticas, visando extrair-lhes a percepção sobre o destaque que lhes foi endereçado, os recursos responsáveis pela diferenciação e a gestão de tais recursos, tendo em vista a atuação num mercado de oligopsônio, típico da cadeia de fornecimento da indústria automobilística. Como resultado, observou-se que as empresas destacadas eram aquelas que alinhavam seus recursos aos objetivos competitivos do setor automobilístico, guiados pela busca de redução de custos e de tempo no desenvolvimento de projetos de novos veículos. Os recursos apontados como determinantes da vantagem competitiva dessas empresas foram: (a) a estrutura tecnológica, (b) a equipe de profissionais e (c) a atuação direta dos proprietários. Como capacidades decorrentes foram citadas: (a) o conhecimento em processo de conformação (no caso de estampos), (a) a habilidade para configuração e atualização da estrutura tecnológica e, (c) a gestão das pessoas chaves na organização. A atuação em mercado de oligopsônio não se mostrou relevante para a diferenciação na geração de valor, mas para a apropriação do valor criado por essas empresas, o que desencadeou o desenvolvimento de novas capacidades: (a) habilidade para exploração de vantagens decorrentes da sazonalidade da demanda, (b) ênfase sobre a gestão econômicofinanceira e, (c) política de reinvestimento dos resultados financeiros da empresa. Discutiu-se o paradigma de comparação para determinação do alcance da vantagem competitiva dessas empresas, tendo em vista a internacionalização da competição do segmento, e identificou-se que a apropriação de valor é uma função da criação de valor, como condição para sustentabilidade das empresas que se encontram na posição de vantagem competitiva.
74

Assessing Mold Risks in Buildings under Uncertainty

Moon, Hyeun Jun 15 July 2005 (has links)
Microbial growth is a major cause of Indoor Air Quality (IAQ) problems. The implications of mold growth range from unacceptable musty smells and defacement of interior finishes, to structural damage and adverse health effects, not to mention lengthy litigation processes. Mold is likely to occur when a favorable combination of humidity, temperature, and substrate nutrient are maintained long enough. As many modern buildings use products that increase the likelihood of molds (e.g., paper and wood based products), reported cases have increased in recent years. Despite decades of intensive research efforts to prevent mold, modern buildings continue to suffer from mold infestation. The main reason is that current prescriptive regulations focus on the control of relative humidity only. However, recent research has shown that mold occurrences are influenced by a multitude of parameters with complex physical interactions. The set of relevant building parameters includes physical properties of building components, aspects of building usage, certain materials, occupant behavior, cleaning regime, HVAC system components and their operation, and other. Mold occurs mostly as the unexpected result of an unforeseen combination of the uncertain building parameters. Current deterministic mold assessment studies fail to give conclusive results. These simulations are based on idealizations of the building and its use, and therefore unable to capture the effect of the random, situational, and sometimes idiosyncratic nature of building use and operation. The presented research takes a radically different approach, based on the assessment of the uncertainties of all parameters and their propagation through a mixed set of simulations using a Monte Carlo technique. This approach generates a mold risk distribution that reveals the probability of mold occurrence in selected trouble spots in a building. The approach has been tested on three building cases located in Miami and Atlanta. In all cases the new approach was able to show the circumstances under which the mold risk could increase substantially, leading to a set of clear specifications for remediation and, in for new designs, to A/E procurement methods that will significantly reduce any mold risk.
75

Micobiota contaminante e ocorrência de aflatoxinas em farinha de milho flocada pré-cozida comercializada em diferentes municípios do Estado da Bahia

Santos, Genivaldo Cruz 14 August 2008 (has links)
Submitted by Glauber Assunção Moreira (glauber.a.moreira@gmail.com) on 2018-08-17T18:17:33Z No. of bitstreams: 1 DISSERTAÇÃO GENIVALDO SANTOS.pdf: 1925505 bytes, checksum: 14d884f698222cff066f3b6db24da095 (MD5) / Approved for entry into archive by Marly Santos (marly@ufba.br) on 2018-08-21T17:14:32Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO GENIVALDO SANTOS.pdf: 1925505 bytes, checksum: 14d884f698222cff066f3b6db24da095 (MD5) / Made available in DSpace on 2018-08-21T17:14:32Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO GENIVALDO SANTOS.pdf: 1925505 bytes, checksum: 14d884f698222cff066f3b6db24da095 (MD5) / As micotoxinas são metabólitos secundários produzidos por fungos e representam um risco potencial para a saúde humana, quando presentes nos alimentos. Dentre as micotoxinas, as aflatoxinas são as mais importantes e mais estudadas. O milho e seus derivados, especialmente a farinha de milho estão entre os principais alimentos encontrados na dieta básica dos brasileiros, particularmente na Bahia. Existem poucos estudos no Estado voltados para a pesquisa de micotoxinas em alimentos derivados do milho. A presença de fungos toxígenos em farinha de milho não se configura necessariamente na presença de micotoxinas, mas representa um alerta para uma maior atenção às práticas agrícolas, tanto na escolha do grão para o plantio, na colheita do milho, no transporte, no processamento para formar a farinha, no armazenamento, como na comercialização deste produto. Os fungos mais freqüentemente isolados em derivados do milho são o Aspergillus spp, Penicillium spp e Fusarium spp. A aflatoxina B1 (AFB1) é um potente carcinógeno classificado como pertencente ao grupo 1 das substâncias potencialmente cancerígenas. O consumo de farinhas de milho flocada pré-cozida com características micotoxicológicas indesejáveis pode ser um perigo para a saúde humana. Tendo em vista a importância dos fungos toxígenos e das micotoxinas, este trabalho teve por objetivo verificar a ocorrência de fungos toxígenos e de aflatoxinas em 112 amostras de farinha de milho flocada pré-cozida comercializada em diferentes municípios do Estado da Bahia no período de junho de 2007 a junho de 2008. As amostras estudadas foram analisadas para isolamento e contagem de fungos em BDA com cloranfenicol. 32% das amostras foram positivas para fungos toxígenos, sendo 50% representados por fungos de armazenamento, 31% de campo e 17% de ambos. Os fungos do gênero Fusarium, Aspergillus e Penicillium foram encontrados com maior freqüência nas amostras que apresentaram atividade de água na faixa entre 0,520,60. 58% das amostras com contaminação fúngica estavam acondicionadas em embalagem de papel. Em relação à presença de aflatoxinas, 14% (16/112) das amostras foram positivas, onde 5% (6/112) apresentaram concentrações acima do limite máximo preconizado na Legislação (20µg/Kg). Os fungos do gênero Aspergillus encontravam-se presentes em 44,4% (16/36) das amostras analisadas. Deste gênero foram isoladas e identificadas três espécies: A. fumigatus 27,8% (10/36), A. flavus 22,2% (8/36) e A. terreus 2,8% (1/36). A análise do potencial toxígeno de 28 isolados de Aspergillus spp. revelou a presença de aflatoxinas em 50% (14/28) das cepas, numa concentração de 24,29 µg/Kg a 6.222 µg/Kg, demonstrando que tais cepas em condições favoráveis de umidade e temperatura no substrato eventualmente produzem aflatoxinas. / ABSTRACT The micotoxins are secondary metabolics produced by fungus and they represent a potential risk for the human health, when found in the foods. Among the micotoxins, the aflatoxins are the most important and more studied. The corn and its derived, especially the maize flour is among the main foods found in the basic diet of the Brazilians, particularly in Bahia. There are few studies in the State on the micotoxins research in foods derived from the corn. The presence of toxigens molds in maize flour is not necessarily configured in the presence of micotoxins, but it represents an alert for a larger attention to the agricultural practices, so much in the choice of the grain for the planting, in the harvest, in the transportation, in the processing, in the storage, as in the commercialization of this product. The molds more frequently isolated in derived of the corn they are the Aspergillus spp., Penicillium spp. and Fusarium spp. The aflatoxina B1 (AFB1) it is a potent carcinogen classified as belonging to the group 1 of the substances potentially cancerous. The consumption of flocked maize flour pre-cooked with characteristics undesirable micotoxicologics can be a danger for the human health. Foccus on the importance of the toxigens molds and the micotoxins, this work had for objective to verify the occurrence of toxigen molds and aflatoxins in 112 samples of maize flour pre-cooked flocked trade in different cities in the State of Bahia from June 2007 to June 2008. The studied samples were analyzed for isolation and counting of molds in BDA with chloranfenicol. 32% of the samples were positive for toxigen molds, being 50% acted by storage molds, 31% of field and 17% of both. The molds of the gender Fusarium, Aspergillus and Penicillium were found more frequently in the samples that presented water activity between 0,52-0,60. 58% of the samples with mold contamination were conditioned in packaging. In relation to the aflatoxins presence, 14% (16/112) of the samples they were positive, where 5% (6/112) they presented concentrations above the maximum limit recommened by the Legislation (20 g/Kg). The molds of the gender Aspergillus were presented in 44,4% (16/36) of the analyzed samples. From this gender were isolated and identified three species: A. fumigatus 27,8% (10/36), A. flavus 22,2% (8/36) and A. terreus 2,8% (1/36). The analysis of the potential toxigen of 28 isolated of Aspergillus spp. revealed the aflatoxins presence in 50% (14/28) of the stumps, in a concentration of 24,29 µg/Kg to 6.222 µg/Kg, demonstrating that such stumps in favorable conditions of humidity and temperature in the substratum eventually produce aflatoxins.
76

USO DE NATAMICINA NO CONTROLE DO DESENVOLVIMENTO DE FUNGOS EM SALAME TIPO ITALIANO

Brustolin, Jean Carlos 25 May 2009 (has links)
This study had as objective to evaluate the behavior of natamycin in different concentrations and forms of application to control the growth of molds in Italian type salami matured in maturation rooms wood through counting of molds and yeasts with swabs and photographic monitoring weekly. Was also evaluated the effect of natamycin on the physical chemical aspects such as water activity, moisture, fat and protein and the sensory aspect evaluated by multiple comparison test. Salami that were evaluated had their casings hydrated with a solution of natamycin with 0.1%, 0.05% and 0,025% before the stuffed and the 0.1% sprayed after smoking in smoking room. It was found that there was a lower count of molds and yeasts in the samples treated with 0.1% natamycin both by immersion or by spraying. The natamycin did not interfere in the sensory and physical chemical aspects. / Este trabalho teve como objetivo avaliar o comportamento da natamicina em diferentes concentrações e forma de aplicação no controle do desenvolvimento de bolores e leveduras em salames tipo italiano maturados em salas de maturação de madeira. O acompanhamento foi realizado através de contagem de bolores e leveduras com swabs e acompanhamento fotográfico semanal. Também foi avaliado o efeito da natamicina em relação a aspectos físico químicos como a atividade de água, umidade, gordura e proteína e o aspecto sensorial foi avaliado através do teste de comparação múltipla. Foram avaliados os salames que tiveram suas tripas hidratadas com solução de natamicina nas concentrações de 0,1%, 0,05% e 0,025% antes do embutimento e ainda a 0,1% aspergido após a defumação em fumeiro. Verificou-se uma contagem de bolores e leveduras menor nas amostras tratadas com concentração de 0,1% de natamicina tanto por imersão quanto por aspersão. A natamicina não interferiu no aspecto sensorial e nem nos aspectos físico químicos.
77

Atmosfera controlada na conservação de erva-mate / Controlled atmosphere in storage of yerba maté

Prestes, Sarah Lemos Cogo 26 August 2014 (has links)
The main aim of this work was to evaluate the effect of controlled atmosphere on postharvest conservation of yerba mate. The following aspects were evaluated: color, chlorophylls concentration, carotenoids and phenolic compounds, foaming, mold and yeast count and the bitter taste of yerba mate. Thus, three experiments were performed from samples of yerba mate from Arvorezinha (RS) and São Mateus do Sul (PR) in the form [1] thickly ground ( cancheada ) and thinly milled ( socada ) were stored in four oxygen levels (1, 3, 6 and 20.9 kPa O2) and four dioxide carbon levels (0, 3, 6 and 18 kPa CO2), and analyzed, after nine months of storage [2] native and cultivated yerba mate stored at room temperature, 1.0 kPa O2 and 3.0 kPa CO2 analyzed after 0, 3, 6 and 12 months of storage. [3] native and cultivated yerba mate from São Mateus do Sul (PR) stored in an atmosphere containing: 20.9 O2 + 0.03 CO2; 0.5 O2 + 0.03 CO2; 1.0 O2 + 0.03 CO2; 1.0 O2 + 3.0 CO2; 1.0 O2 + 18 CO2 which were analyzed after six months of storage. The results demonstrate that the condition 1.0 kPa O2 maintain the yerba mate greener and with a higher chlorophylls concentration and total phenolic compounds. The CO2 partial pressure maintain yerba mate coloration greener and with a higher chlorophylls concentrationand total phenolic compounds, regardless of the level used, in the yerba mate from both cultivation areas. The yerba mate thickly ground ( cancheada ) presented a better storage potential than the thinly milled ( socada ). Total chlorophyll concentration reduced exponentially during the storage time independently of the storage condition, form of cultivation and place that the yerba mate was cultivated, since the total carotenoid independently of the form and place of cultivation decreased to 3 months storage under atmosphere of 1.0 kPa O2. When stored in 3.0 kPa CO2, the reduction was over 12 months of storage. Dioxide carbon increasing in the storage chamber increases the phenolic compounds concentration until six month of storage. Raw material originated from São Mateus do Sul-PR has higher chlorophyll concentration, greener color resulting in greater storage potential of this yerba mate. When evaluating the combination of gases, we observed that CA condition with 0.5 kPa O2 + 0.03 kPa CO2 maintained yerba mate greener, with higher chlorophyll concentration and phenolic compounds concentrations after 6 months of storage. As for the foam, controlled atmosphere had a positive effect on its maintenance. The native yerba mate showed higher green color preservation in relation to the cultivated. There was no increase in yeast and molds in yerba mate of CA storage. Yerba mate, independently of type, stored in 1.0 kPa O2 + 0.03 kPa CO2 was selected in a sensorial panel as the most bitter and under air conditions (20.9 kPa O2 + 0.03 kPa CO2) as the lesser bitter, however, the most preferred yerba mate stored under 0.5 O2 kPa + 0.03 kPa CO2. / O objetivo principal deste trabalho foi avaliar o efeito da atmosfera controlada na conservação pós-colheita de erva-mate. Para tanto os seguintes aspectos foram avaliados: coloração, concentração de clorofilas, carotenóides e compostos fenólicos totais, formação de espuma, contagem de bolores e leveduras e o sabor amargo do chimarrão. Para tal, foram efetuados três experimentos a partir de amostras de erva-mate provenientes de Arvorezinha (RS) e São Mateus do Sul (PR), na forma [1] cancheada e socada, foram armazenadas em quatro níveis distintos de oxigênio (1, 3, 6 e 20,9 kPa de O2) e quatro níveis distintos de gás carbônico (0, 3, 6 e 18 kPa de CO2), as quais foram analisadas ao final de nove meses de armazenamento. [2] Erva-mate nativa e cultivada armazenadas a temperatura ambiente, 1,0 KPa de O2 e 3,0 KPa de CO2, analisadas após 0, 3, 6 e 12 meses de armazenamento. [3] Erva-mate nativa e cultivada provenientes de São Mateus do Sul (PR) armazenadas em atmosfera, contendo: 20,9 O2+0,03 CO2; 0,5 O2+0,03 CO2; 1,0 O2+0,03 CO2; 1,0 O2+3,0 CO2; 1,0 O2+18 CO2 as quais foram analisadas ao final de seis meses de armazenamento. Os resultados demonstram que a condição 1,0 kPa de O2 mantém a erva-mate mais verde, maior teor de clorofilas e compostos fenólicos totais. A pressão parcial de CO2, independente do nível, mantém a coloração da erva-mate mais verde, maior teor de clorofilas e compostos fenólicos totais, nos dois locais de cultivo. A erva-mate cancheada apresentou um melhor potencial de armazenamento do que a erva-mate socada. Concentração de clorofila total reduziu exponencialmente durante o tempo de armazenamento, independentemente da condição de armazenamento, forma de cultivo e local que a erva-mate foi cultivada, já os teores de carotenóides totais independente da forma e local de cultivo, apresentaram redução até os 3 meses de armazenamento sob atmosfera de 1,0 KPa de O2, já quando armazenadas em 3,0 KPa de CO2, a redução dos carotenóides foi ao longo dos 12 meses de armazenamento. A presença de CO2 na atmosfera de armazenamento eleva a concentração de compostos fenólicos totais até seis meses. A matéria-prima proveniente de São Mateus do Sul-PR tem maior preservação da cor verde o que resulta em maior potencial de armazenamento. Ao avaliar a combinação dos gases, foi possível verificar que a condição 0,5 O2 + 0,03 CO2 manteve a erva-mate mais verde, maior teor de clorofilas e compostos fenólicos totais após seis meses de armazenamento. Quanto à espuma, a atmosfera controlada apresentou efeito positivo na sua manutenção. A erva-mate nativa apresentou uma maior preservação da cor verde do que a erva-mate cultivada. Não houve aumento das contagens de bolores e leveduras na erva-mate nas condições de armazenamento em AC. A erva-mate, indiferente do tipo, armazenada a 1,0 O2+0,03 CO2 foi a selecionada sensorialmente como a mais amarga e erva-mate armazenada a 20,9 O2+0,03 CO2 como a menos amarga, no entanto a preferida foi a erva-mate armazenada a 0,5 O2+0,03 CO2.
78

Estudo comparativo entre duas técnicas para montagem do modelo de gesso de arcadas superiores em articulador semi-ajustável / A comparative study between two techniques to mount the maxillary cast in semi-adjustable articulator

Rogério Ribas da Costa 20 November 2001 (has links)
Este estudo avaliou a habilidade de duas técnicas, uma convencional e uma de transferência direta do molde, para a montagem do modelo de gesso maxilar no articulador. Um único paciente do sexo feminino, 39 anos, portador de arcada superior de Classe I de Kennedy (desdentado posterior bilateral) foi usado para esta investigação. Foram obtidos 20 modelos de gesso em cada técnica, totalizando 40 montagens nos articuladores. Com o modelo maxilar montado, cada articulador foi fotografado do mesmo lado direito da radiografia em norma lateral da paciente, obtida com o arco facial montado em sua face. As medidas analisadas nos traçados realizados sobre as fotografias e na radiografia, foram obtidas calculando-se o ângulo entre a interseção do plano oclusal da maxila e o plano de referência horizontal (plano de Frankfurt), representado pelo arco facial na radiografia da paciente, comparando-o com o ângulo entre o plano oclusal do modelo de gesso e o ramo superior do articulador em ambas as técnicas, por meio do software UTHSCSA Image Tool. O dados foram submetidos à análise estatística. Os resultados deste estudo demonstraram uma capacidade maior de reprodução daquele ângulo quando uma técnica de transferência direta do molde é usada. Da mesma maneira, foi verificado uma distorção significante na reprodutibilidade dos modelos montados pela técnica convencional. / This study assessed the ability of two techniques to mount the maxillary cast in the articulator, a conventional technique and one of direct transfer of the maxillary arch impression from the patient\'s mouth to the articulator. A single female subject, 39 years old, with a partially edentulous arch, Kennedy´s Class I, was used in this investigation. It was obtained 20 casts in each technique, totaling 40 cast mountings in the articulators. With the maxillary cast mounted, each articulator was photographed in the same right side of the lateral skull cephalometric radiograph of the patient with the face-bow mounted in her face. The measures obtained by the photographic and cephalometric tracings were evaluated by calculating the angle made by the intersection of the maxillary occlusal plane with craniofacial horizontal reference plane (Frankfort´s plane) on the patient´s cephalogram and comparing it with the angle between the occlusal plane of the cast with the upper member of the articulators in both techniques using the UTHSCSA Image Tool computerized program. The measuring data was submitted to the statistical analysis. The results of this study demonstrated a better capacity of reproduction of that angle when a direct transfer technique is used. In the same way, it was found a significant low level of reproducibility in mounting the maxillary cast when a conventional technique is used.
79

Optimalizace jádra formy na vstřikování plastů / Optimization of core molds for injection molding

Stavárek, Václav January 2019 (has links)
Diplomová práce vznikla ve spolupráci s průmyslovým partnerem, který vyrábí elektrické komponenty pro automobilový průmysl. Tato firma se potýká s problémy často se porušujících jader v některých jejich formách na vstřikování plastů, vyrábějících převážně housingy pro konektory. Firma disponuje licencemi na komerční software pro simulaci injekčního vstřikování Moldflow a Moldex3D a také pro simulaci metodou konečných prvků Ansys. Nejprve jsou shrnuty teoretické poznatky ohledně injekčního vstřikování a jeho simulace, řešení problémů interakce těles s tekutinou a únavy materiálu. Poté je popsán proces stanovení únavové životnosti jádra formy s využitím výše zmíněného softwaru. Proces je vysvětlen na příkladu konkrétní formy ve výrobě této firmy. Je zvolen takový přístup vyhodnocení únavy, který nejvíce odpovídá současné životnosti jader, a ten je pak použit pro analýzu vlivu změny geometrie jádra a parametrů vstřikování. Změny ostatních parametrů, které simulace neumožňuje zahrnout, jsou rovněž navrhnuty a pokud možno odůvodněny jinými způsoby. Jedno z doporučení je přidání zaoblení na obě jádra, což by mohlo prodloužit životnost toho problematičtějšího z nich z 30 dnů na více než 320 dnů. Toto by mohlo znamenat úspory až 10 600 EUR ročně. Další doporučení je změnit způsob obrábění jader a také přidat jejich tepelné zpracování.
80

Studium odolnosti povrchových úprav ETICS vůči biotickému napadení / Study of the ETICS surface resistance to biotic attack

Těžká, Adéla January 2020 (has links)
This diploma thesis deals with the study of resistance of ETICS surface treatments to biotic attack. The theoretical part elaborates a research focused on biotic attack of facades of buildings insulated by contact insulation systems ETICS. Based on the information obtained during the elaboration of the bachelor thesis and further study, the optimization methodology of ETICS surface treatment resistance to biotic attack proposed in 2018 is elaborated. In the practical part, the proposed methodology is verified, evaluated and recommendations concerning the suitability of using the proposed methodology in construction practice are implemented.

Page generated in 0.0391 seconds