988 resultados para Violeta Parra


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Este trabalho teve por objetivo verificar a viabilidade do uso de digitalizador de imagens manual, acoplado a um microcomputador, para a avaliação do consumo de folhas de soja, por lagartas de 5o instar de Anticarsia gemmatalis Hübner (Lep.: Noctuidae), em comparação com o método de pesagem e do planímetro, baseando-se na eficiência dos métodos e no tempo gasto para a avaliação. Os testes foram realizados utilizando-se folhas de soja `IAC 8' e lagartas criadas em dieta artificial. Foram realizados 2 tipos de teste: 1o) oferecimento de folíolos inteiros de soja às lagartas e, 2o) oferecimento de disco de folhas de área conhecida. No 1o teste comparou-se o método de pesagem com o digitalizador de imagens (scanner); no 2o experimento foram comparados o método do planímetro com o digitalizador de imagens que emprega o programa PCXAREA. Os resultados obtidos demonstraram que não existem diferenças nas medições de folíolos e discos de soja consumidos por A. gemmatalis quando comparados os métodos tradicionais (planímetro e pesagem) e o de digitalização de imagens. A medição com o digitalizador reduziu o tempo de avaliação em 88,5% e 87%, em relação ao planímetro e método de pesagem, respectivamente, sendo plenamente viável a sua utilização.

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The oil and petrochemical industry is responsable to generate a large amount of waste and wastewater. Among some efluents, is possible find the benzene, toluene, ethilbenze and isomers of xilenes compounds, known as BTEX. These compounds are very volatily, toxic for environment and potencially cancerigenous in man. Oxidative advanced processes, OAP, are unconventional waste treatment, wich may be apply on treatment and remotion this compounds. Fenton is a type of OAPs, wich uses the Fenton s reactant, hydrogen peroxide and ferrous salt, to promove the organic degradation. While the Photo-Fenton type uses the Fenton s reactant plus UV radiation (ultraviolet). These two types of OAP, according to literature, may be apply on BTEX complex system. This project consists on the consideration of the utilization of technologies Fenton and Photo-Fenton in aqueous solution in concentration of 100 ppm of BTEX, each, on simulation of condition near of petrochemical effluents. Different reactors were used for each type of OAP. For the analyticals results of amount of remotion were used the SPME technique (solid phase microextraction) for extraction in gaseous phase of these analytes and the gas chromatography/mass espectrometry The arrangement mechanical of Photo-Fenton system has been shown big loss by volatilization of these compounds. The Fenton system has been shown capable of degradate benzene and toluene compounds, with massic percentage of remotion near the 99%.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Embora a escassez de água seja reconhecida como um dos principais problemas mundiais a ser enfrentado pela humanidade, padrões comportamentais ecologicamente insustentáveis ainda persistem. Assim, o objetivo deste estudo foi analisar determinantes do comportamento pró-ambiental relativo à água, bem como os significados que lhe são atribuídos por alunos do ensino médio do Centro Federal de Educação Tecnológica do Rio Grande do Norte, em Natal. Compuseram a amostra de conveniência 315 estudantes, 146 mulheres e 169 homens, que responderam a um questionário sobre uso e percepção da água, contendo também indicadores de pró-ambientalismo, cuidado ambiental, desenvolvimento sustentável, perspectiva temporal, externalidades e coletivismo, além de inquérito sócio-demográfico. Para os participantes, água é sinônimo de vida, muito embora a relação que mantém com ela parece dúbia e, muito mais funcional que ecológica; consideram-na um recurso finito, um patrimônio indispensável à vida, contudo não foi observada coerência entre as concepções manifestadas e os comportamentos auto-relatados de uso da água. Os resultados encontrados apontaram preditores importantes do comportamento pró-ambiental relativo à água: sexo do respondente, Escala Novo Paradigma Ecológico e deixar forma de contato para participar de campanhas futuras. Seja para aprofundamento teórico em novos estudos, seja para auxiliar na elaboração de programas de educação ambiental, que poderiam contribuir para inibir os efeitos de uma cultura de consumo e de uma visão utilitarista da água, ampliando esforços individuais e coletivos para a preservação de bens comuns, como a água. Palavras-chave: psicologia ambiental; sustentabilidade; água; comportamento próambiental. x xi Abstract Although water scarcity is recognized as one of the main world-wide problems to be faced by human kind, ecologically unsustainable patterns of behavior still persist. Thus, the objective of this study was to analyze pro-environmental behavior related to water, as well as meanings associated to it by high school students of Federal Center of Technological Education of Rio Grande do Norte, in Natal. The convenience sample was composed by 315 students, 146 women and 169 men, who answered a questionnaire about use and perception of water, containing indicators of proenvironmentalism, environmental care, sustainable development, time perspective, externalities and collectivism, besides socio-demographic items. According to participants, water is synonymous of life, even though the relationship they present with it is ambiguous, much more functional than ecological; they consider it a finite resource, an indispensable life patrimony, however there was no coherence between such conceptions and the self-reported behaviors of water use. Results indicated three important predictors of pro-environmental behavior: sex of respondent, New Ecological Paradigm Scale and telephone/address left for eventual contact to participate in future environmental campaigns. They may be used in additional studies for theoretical development, or to assist in the planning of programs of environmental education, aimed at the inhibition of the effects of a culture of consumption and of an utilitarian perception of water, extending individual and collective efforts towards the preservation of common resources as water

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Although water scarcity is recognized as one of the main world-wide problems to be faced by human kind, ecologically unsustainable patterns of behavior still persist. Thus, the objective of this study was to analyze pro-environmental behavior related to water, as well as meanings associated to it by high school students of Federal Center of Technological Education of Rio Grande do Norte, in Natal. The convenience sample was composed by 315 students, 146 women and 169 men, who answered a questionnaire about use and perception of water, containing indicators of proenvironmentalism, environmental care, sustainable development, time perspective, externalities and collectivism, besides socio-demographic items. According to participants, water is synonymous of life, even though the relationship they present with it is ambiguous, much more functional than ecological; they consider it a finite resource, an indispensable life patrimony, however there was no coherence between such conceptions and the self-reported behaviors of water use. Results indicated three important predictors of pro-environmental behavior: sex of respondent, New Ecological Paradigm Scale and telephone/address left for eventual contact to participate in future environmental campaigns. They may be used in additional studies for theoretical development, or to assist in the planning of programs of environmental education, aimed at the inhibition of the effects of a culture of consumption and of an utilitarian perception of water, extending individual and collective efforts towards the preservation of common resources as water

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Violacein is a violet pigment isolated from many gram-negative bacteria, especially from Chromobacterium violaceum, a betaproteobacterium found in the Amazon River in Brazil. It has potential medical applications as an antibacterial, fungicide, anti-tryptanocidal, anti-ulcerogenic and anti-cancer drug, among others. Furthermore, its pro-oxidant activity has been suggested, but only in two specific tumor lineages. Thus, in the present study, the prooxidant effects of violacein were investigated in both normal and tumor cells, seeking to evaluate the cell responses. The evaluation of violacein cytotoxicity using the Trypan blue dye exclusion method indicated that CHO-K1 cells were more resistant than tumor HeLa cells. The oxidative stress induced by violacein was manifested as an increase in intracellular SOD activity in CHO-K1 and MRC-5 cells at a specific concentration range. Nevertheless, a decrease was detected specifically at 6-12 μM in HeLa and MRC-5 cells. Interestingly, the increase in SOD activity was not followed by a concomitant increase in catalase activity. Regarding to oxidative stress biomarkers, increased protein carbonylation and lipid hydroperoxides levels were detected respectively in CHO-K1 and MRC-5 cells treated with violacein at 1.5-3 μM and 3 μM, which may be an evidence that this compound causes oxidative stress specifically in these conditions. Additionally, it is believed that the decline in cell viability observed in MRC-5 cells and HeLa treated with violacein at 6-12 M is due to mechanisms not related to oxidative stress. Moreover, the results suggested that violacein might cause oxidative stress by increasing endogenous levels of O2 -, since the occurrence of an expressive change in SOD activity. In addition, in order to evaluate the antioxidant activity of violacein in the absence of a biological system, the total antioxidant and iron chelating activity were evaluated, so that antioxidant activities were detected at 30 and 60 μM of violacein. Altogether, the results indicate that although oxidative stress is triggered by incubation with violacein, it did not seem to be high enough to cause serious damage to cell biomolecules in HeLa cells and only at specific concentrations in CHOK-1 and MRC-5 cells. Comparing the results obtained in cell culture and the in vitro antioxidant activity evaluation, the results confirmed that violacein presents opposing oxidant features when in presence or absence of a biological system and the antioxidant character only occurs at high concentrations of the pigment.

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The objective of this study was to evaluate the effects of feeding cattle with isoprotein and isoenergetic diets, with and without the addition of polyclonal antibody preparation (PAP), yeasts (YST) or monensin sodium (MON) on performance, carcass characteristics and gain cost in feedlot. Ninety-five 20-month old bullocks (323.3±21.8 kg) were distributed in 25 pens. The completely randomized experimental design had a 2 × 2 + 1 factorial arrangement and the treatments were replicated 5 times. There was no effect of MON for DMI throughout the feedlot period; however, MON reduced the dry matter intake (DMI) in g/kg of BW in the first 28 days when compared with the other treatments. The gain cost decreased with MON addition in relation to the other treatments. Inclusion of YST decreased average daily gain (ADG), final body weight, hot carcass weight, carcass weight, gain to feed ratio and DMI in g/kg body weight, worsening feed conversion and increasing the gain cost in the feeding periods. Inclusion of PAP increased ADG and decreased the gain cost, besides improving feed conversion. For MON and PAP, a difference was found for kidney-pelvic fat and kidney-pelvic fat per 100 kg of hot carcass weight. For MON and YST, there was a difference in ADG, feed conversion, gain cost and carcass yield and kidney-pelvic fat per 100 kg of hot carcass. Treatment YST worsened performance in relation to the non-supplemented treatments. Feeding PAP to animals did not influence performance and carcass characteristics of bullocks in feedlot negatively. Thus, PAP shows potential to substitute MON in cattle feeding using isoprotein and isoenergetic diets.

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O objetivo deste trabalho foi avaliar os efeitos da restrição alimentar e de dieta de suplementação com vitaminas D e E sobre o desempenho e características de carcaça de novilhas Canchim. Vinte e quatro fêmeas, com peso vivo inicial médio de 251,95±18,49 kg, foram distribuídas em quatro tratamentos: alimentação em quantidade restrita e não restrita, com e sem suplementação de vitaminas D e E. Utilizou-se o delineamento inteiramente casualizado, em arranjo fatorial 2x2, com seis repetições. Os animais com alimentação restrita receberam, por 48 dias, 70% da dieta fornecida ao grupo de alimentação não restrita. Após o período de restrição (peso médio de 300,10 kg), eles voltaram a receber ração à vontade por mais 77 dias, até atingirem peso de abate de 380 kg. As avaliações foram feitas ao final dos períodos de restrição e de realimentação. Não foi observado efeito da restrição alimentar sobre o desempenho animal. Novilhas que não receberam suplementação vitamínica apresentaram maiores índices de fragmentação miofibrilar, luminosidade e mastigabilidade, e menor força de cisalhamento. A restrição alimentar não afeta o desempenho nem as características de carcaça das novilhas Canchim, e a suplementação com vitaminas D e E não melhora a qualidade da carne.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)