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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.
201

Développement de biocapteurs électrochimiques pour la détection de polluants environnementaux et pour la sécurité alimentaire / Development of electrochemical biosensors for environmental pollutant and food safety monitoring

Guo, Zhenzhong 19 March 2014 (has links)
De nos jours, les biocapteurs électrochimiques constituent des outils rapides, fiables, rentables et sans marquage pour la détection sur site des polluants environnementaux et l’évaluation des critères de sécurité alimentaire et pour la détection des résidus militaires sur le terrain. Nous avons développé des biocapteurs d’affinité basés sur des récepteurs biologiques pour la détection électrochimique de l'estradiol dans des échantillons environnementaux et de molécules odorantes dans l'adultération de viande de porc. Des biocapteurs sensibles, sélectifs, rapides, simples reproductible, stables et efficaces ont été élaborés. En outre, une autre stratégie basée sur des nanomatériaux intégrés a été employée pour élaborer un capteur biomimétique pour la détection d’explosifs, qui a montré de bonnes qualités dans la protection de l'environnement. A la fin du manuscrit, certaines perspectives sont discutées / Nowadays, electrochemical biosensors are rapid, reliable, cost-effective and label-free tools for in field monitoring of environmental pollutants, for assessing the food safety criterion and for detection of the territory military residues. We developed biological receptors based affinity biosensors for electrochemical detection of estradiol in environment samples and odorant molecules in pork meat adulteration. The sensitive, selective, rapid, simple, repetitive, stable and effective biosensors were produced. In addition, another strategy entrapment based on integrated nano-material was used to produce a biomimetic sensor for explosives detection, which has shown good valuable in environmental protection and homeland security. In the end, certain significant prospective are discussed
202

Transformações do carbono e do nitrogênio no solo e produção de aveia com o uso de dejetos de suínos em plantio direto / Carbon and nitrogen transformations in soil and oat production with the use of pig manure in no-tillage system SYSTEM

Marques, Marcelo Gonçalves 12 August 2005 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of pig manure, especially of the deep-bedding manure, is not so often in the winter cover crops, preceding the summer commercial plantation. The aim of this study was to evaluate the carbon and nitrogen dynamics in soil and the black oat production with the use of pig slurry and deep-bedding manure. Emphasis has been given to the losses of N for ammonia volatilization, to the variation in the amounts of mineral N, to the decomposition of the organic materials and the oat N accumulation. Three experiments were conducted in field conditions in a typic Hapludalf soil, at the experimental area of the Soil Science Department, Federal University of Santa Maria, Santa Maria, RS, from May to October of 2003. In the first experiment, the ammonia volatilization was evaluated after the application of the pig slurry and deep-bedding manure on the crop residues of corn, in the following treatments: T1 - crop residues of corn (RCM) + 44,2 m3 ha-1 of pig slurry; T2 - RCM + 17,9 Mg ha-1 deep-bedding; T3 - RCM without incorporation; T4 - RCM + 44,2 m3 ha-1 pig slurry with incorporation and T5 - RCM with incorporation. The N losses by ammonia volatilization were higher in deep-bedding manure than in the pig slurry, proportionally. No loss of the N for ammonia volatilization was observed with the incorporation of the pig slurry in the soil. The highest ammonia emissions for the atmosphere (65%) occurred during the first day after the application of the pig slurry and the deep-bedding manure in the field. In the second experiment the N dynamics was evaluated in the soil during the black oat cultivation, through the temporary variation of the amounts of mineral N (NNH4+ and N-NO2- + N-NO3-). Also, the dry matter production and N accumulation in oat in the following treatments: T1 crop residues of corn (RCM) + 44,2 m3 ha-1 of pig slurry of ; T2 - RCM + 17,9 Mg ha-1 of deep-bedding manure; T3 - RCM + 9,7 Mg ha-1 of deep-bedding manure; T4 - RCM + 50 kg ha-1 of N-urea and T5 - RCM. For equivalent amounts of mineral N applied to the soil with the deep-bedding manure and the pig slurry, the amount of mineral N in the soil was higher in the pig slurry, evidencing a lower rate of mineralization of organic N of the deep-bedding manure. The ammoniacal N of the pig slurry was quickly nitrified in the soil and N-NO3- produced moved in the soil profile. This shows the evidences of lossing N by lixiviation. The deep-bedding manure presented low potential of supply of N to the oat, compared to the pig slurry. Only 22.5% of the ammoniacal N applied with the pig slurry was recovered in the oat. In the physiologic maturation of the oat 52.6% of ammoniacal N applied with the pig slurry was found in the soil-plant system. In the third experiment was evaluated the effect of the addition of pig manure on the decomposition of the crop residues of corn (RCM), without incorporation to the soil. The emission of C-CO2 was quantified continually for 62 days in the following treatments: T1 - Soil + RCM + 44,3 m3 ha-1 of pig slurry; T2 - Soil + RCM + 17,9 Mg ha-1 deep-bedding manure; T3 - Soil + RCM; T4 - Soil + 44,3 m3 ha-1 of pig slurry; T5 - Soil + 17,9 Mg ha-1 deep-bedding manure and T6 - Soil. The decomposition was higher in the pig slurry than in the deep bedding, revealing the highest degree of recalcitrant of the carbon compost of the deep-bedding manure. The decomposition of the crop residues of corn, with high C/N ratio, was improved with the application to the pig slurry. / O uso de dejetos de suínos, especialmente da cama sobreposta, é relativamente pouco freqüente em plantas de cobertura de solo no inverno, antecedendo às culturas comerciais de verão. Este trabalho foi realizado para avaliar a dinâmica do carbono e do nitrogênio no solo e a produção da cultura da aveia preta com o uso de dejetos líquidos e cama sobreposta de suínos, com ênfase às perdas de N por volatilização de amônia, à variação nas quantidades de N mineral no solo, à decomposição dos materiais orgânicos e ao acúmulo de N pela aveia. Para isso foram conduzidos três experimentos em condições de campo, no período de maio a outubro de 2003, na área experimental do Departamento de Solos da Universidade Federal de Santa Maria (UFSM) em um Argissolo Amarelo distrófico arênico. No primeiro experimento foi avaliada a volatilização de amônia após a aplicação de dejetos líquidos e cama sobreposta de suínos sobre os resíduos culturais de milho, nos seguintes tratamentos: T1- Resíduos culturais de milho (RCM) + 44,2 m3 ha-1 de dejetos líquidos de suínos; T2- RCM + 17,9 Mg ha-1 de cama sobreposta; T3- RCM sem incorporação ao solo; T4- RCM + 44,2 m3 ha-1 de dejetos líquidos de suínos com incorporação e T5- RCM com incorporação. Proporcionalmente, as perdas de N por volatilização de amônia foram maiores na cama sobreposta de suínos do que nos dejetos líquidos. Quando os dejetos líquidos de suínos foram incorporados ao solo não foram observadas perdas de N por volatilização de amônia. As maiores emissões de amônia para a atmosfera (65% do total emitido) ocorreram durante o primeiro dia após a aplicação dos dejetos líquidos e da cama sobreposta no campo. No segundo experimento avaliou-se a dinâmica do N no solo durante o cultivo da aveia preta, através da variação temporal das quantidades de N mineral (N-NH4+ e N-NO3- + N-NO2-), e também a produção de matéria seca a acúmulo de N da aveia nos seguintes tratamentos: T1- Resíduos culturais de milho (RCM) + 44,2 m3 ha-1 de dejetos líquidos de suínos; T2- RCM + 17,9 Mg ha-1 de cama sobreposta; T3- RCM + 9,7 Mg ha-1 de cama sobreposta; T4- RCM + 50 kg ha-1 de N-uréia e T5- RCM. Para quantidades equivalentes de N mineral aplicadas ao solo com a cama sobreposta e os dejetos líquidos, a quantidade de mineral no solo durante o cultivo de aveia foi maior nos dejetos líquidos, evidenciando a baixa taxa de mineralização do N orgânico da cama sobreposta . O N amoniacal dos dejetos líquidos foi rapidamente nitrificado no solo e o N-NO3 - produzido se deslocou no perfil do solo havendo evidências de perdas desta forma de N por lixiviação. A cama sobreposta de suínos apresentou menor potencial de fornecimento de N à aveia, comparado com os dejetos líquidos de suínos. Apenas 22,5% do N amoniacal aplicado com os dejetos foi recuperado pela cultura da aveia. No florescimento pleno da aveia 52,6% do N amoniacal aplicado com os dejetos líquidos foi encontrado no sistema solo-planta. No terceiro experimento foi avaliado o efeito da adição de dejetos sobre a decomposição dos resíduos culturais do milho (RCM), sem incorporação ao solo. Para isso, foi quantificada a emissão de C-CO2 continuamente durante 62 dias nos seguintes tratamentos: T1- Solo + RCM + 44,3 m3 ha-1 de dejetos líquidos; T2- Solo + RCM + 17,9 Mg ha-1 de cama sobreposta; T3- Solo + RCM; T4- Solo + 44,3 m3 ha-1 de dejetos líquidos; T5- Solo + 17,9 Mg ha-1 de cama sobreposta e T6- Solo. A decomposição dos dejetos líquidos foi maior do que a cama sobreposta de suínos, revelando o maior grau de recalcitrância dos compostos carbonados da cama sobreposta. A decomposição dos resíduos culturais de milho, com elevada relação C/N, foi favorecida pela aplicação dos dejetos líquidos de suínos, sendo que a mesma aumentou em 21%.
203

Hodnocení vlivu znečištění ovzduší na cenu bydlení v Praze / Impact of air pollution on property values in Prague

Kaloč, Jiří January 2011 (has links)
This thesis is aimed at the topic of economical evaluation of environmental goods, namely at estimating willingness to pay utilizing the hedonic price model. The theoretical part describes the impact air pollution has on the environment and human health. Methods of evaluation are also discussed with special attention on the hedonic approach. Goal of this thesis is to evaluate the impact of air pollution by applying the hedonic model to the real-estate market in Prague, thus giving the authorities a basis for their air pollution management.
204

Compostagem de resíduo sólido de indústria oleoquímica submetido a três inoculantes / Composting of solid residue from the oil industry submitted to three inoculants

Rigolin, Isabela Marega 08 August 2013 (has links)
Made available in DSpace on 2016-01-26T18:56:29Z (GMT). No. of bitstreams: 1 Isabela Marega Rigolin.pdf: 2206134 bytes, checksum: a04daea692c9eb3116904c47f5416325 (MD5) Previous issue date: 2013-08-08 / One way to reduce the concentration of waste through composting is being considered as an alternative privileged treatment. This study aimed to evaluate the compostability of industrial waste through monitoring of chemical parameters. The experiment was conducted at the Agricultural Sciences College, School of Agronomy, located in Campus II, Universidade do Oeste Paulista UNOESTE in Presidente Prudente/SP. For treatments we used the residue of an industrial company in the oilochemical, properly characterized chemically before the mixtures. The treatments were arranged in compost piles and characterized as follow way: (T1) = Test, (T2) = 75% Proportion of Principal residue + 25% Sewage Sludges (ETE) (3:1), (T3) = Proportion of 50% of the residue Principal + 50% Sewage Sludges (ETE) (1:1), (T4) = 25% Proportion of Principal residue + 75% of Sewage Sludges (ETE) (1:3) , (T5) = 75% Proportion of Principal residue + 25% Mineral Fertilizer (3:1), (T6) = 50% Proportion of Principal residue + 50% Mineral Fertilizer (1:1), (T7) = 25% Proportion of Principal residue + 75% Mineral Fertilizer (1:3), (T8 = 75% Proportion of Principal residue + 25% Farmyard Manure natural; (T9) = 50% Proportion of Principal residue l + 50% Proportion of Principal residue; (T10) = 25% Proportion of Principal residue + 75% Farmyard Manure natural . The samples were dried at 65 ° C for 72 hours, after that it was grinded to determine the following parameters: electrical conductivity (EC) in relation to water, pH CaCl2 0.01 mol L-1, Moisture (%) of the samples removed 65ºC; Relation C/N; Content of Organic Matter (MOT) and total C. The results were submitted to analysis of variance and mean comparison test F at 5% probability, and where relevant treatment effects were evaluated by applying the polynomial regression models. The best model to fit the data was selected based on the significance degree of the coefficient of determination (R²). The data obtained showed that composting is a technique which may be effective in the treatment of waste from the oil industry, which requires the addition of inoculum and nutrients to provide the necessary conditions for microbial activity, the proportion of 25 RI% + 75% of LE. It was considered as a treatment which obtained an important result given the difficult to composting RI, that the period of 120 days was not enough to transform into compost humified and the addition of mineral fertilizer provided no significant effect. / Uma das formas de reduzir a concentração de resíduos é através da compostagem, sendo considerada como uma alternativa privilegiada de tratamento. Este trabalho teve como objetivo avaliar a compostabilidade de um resíduo industrial através do monitoramento de parâmetros químicos. O experimento foi conduzido na Faculdade de Ciências Agrárias, do Curso de Agronomia, localizada no Campus II, na Universidade do Oeste Paulista - UNOESTE, em Presidente Prudente/SP. Para os tratamentos, utilizou-se o resíduo industrial de uma empresa do setor de oleoquímica, devidamente caracterizado quimicamente antes da efetivação das misturas. Os tratamentos foram dispostos em pilhas de compostagem e caracterizados da seguinte forma: (T1) = Testemunha; (T2) = Proporção de 75% do Resíduo Principal + 25% de Lodo de Esgoto (ETE) (3:1); (T3) = Proporção de 50% do Resíduo Principal + 50% de Lodo de Esgoto (ETE) (1:1); (T4) = Proporção de 25% do Resíduo Principal + 75% de Lodo de Esgoto (ETE) (1:3); (T5) = Proporção de 75% do Resíduo Principal + 25% de Fertilizante Mineral (3:1); (T6) = Proporção de 50% do Resíduo Principal + 50% de Fertilizante Mineral (1:1); (T7) = Proporção de 25% do Resíduo Principal + 75% de Fertilizante Mineral (1:3); (T8) = Proporção de 75% do Resíduo Principal + 25% Esterco de Curral in natura; (T9) = Proporção de 50% do Resíduo Principal + 50% Esterco de Curral in natura; (T10) = Proporção de 25% do Resíduo Principal + 75% Esterco de Curral in natura. As amostras coletadas foram secas à 65 oC durante 72 horas e depois moídas para a determinação dos seguintes parâmetros: Condutividade elétrica (Ce) em água na relação; pH em CaCl2 0,01 mol L-1, Umidade (%) das amostras eliminada à 65oC; Relação C/N, Teor de Matéria Orgânica Total (MOT) e C total. Os resultados foram submetidos à análise de variância e ao teste de comparação de médias F ao nível de 5% de probabilidade e, quando pertinente os efeitos dos tratamentos foram avaliados aplicando-se os modelos de regressão polinomial. O melhor modelo para o ajuste dos dados foi escolhido em função do grau de significância do coeficiente de determinação (R2). De acordo com os dados obtidos verificou-se que a compostagem é uma técnica que poderá ser eficiente no tratamento do resíduo proveniente da indústria oleoquímica, sendo necessária, a adição de inoculantes e nutrientes que forneçam condições necessárias para a atividade microbiana; a proporção de 25% do RI + 75% de LE, foi considerada como um tratamento que obteve um resultado relevante diante da dificuldade de compostagem do RI; que o período de 120 dias não foi suficiente para transformação em composto humificado e a adição de fertilizante mineral não proporcionou efeito significativo.
205

Compostagem de resíduo sólido de indústria oleoquímica submetido a três inoculantes / Composting of solid residue from the oil industry submitted to three inoculants

Rigolin, Isabela Marega 08 August 2013 (has links)
Made available in DSpace on 2016-07-18T17:51:12Z (GMT). No. of bitstreams: 1 Isabela Marega Rigolin.pdf: 2206134 bytes, checksum: a04daea692c9eb3116904c47f5416325 (MD5) Previous issue date: 2013-08-08 / One way to reduce the concentration of waste through composting is being considered as an alternative privileged treatment. This study aimed to evaluate the compostability of industrial waste through monitoring of chemical parameters. The experiment was conducted at the Agricultural Sciences College, School of Agronomy, located in Campus II, Universidade do Oeste Paulista UNOESTE in Presidente Prudente/SP. For treatments we used the residue of an industrial company in the oilochemical, properly characterized chemically before the mixtures. The treatments were arranged in compost piles and characterized as follow way: (T1) = Test, (T2) = 75% Proportion of Principal residue + 25% Sewage Sludges (ETE) (3:1), (T3) = Proportion of 50% of the residue Principal + 50% Sewage Sludges (ETE) (1:1), (T4) = 25% Proportion of Principal residue + 75% of Sewage Sludges (ETE) (1:3) , (T5) = 75% Proportion of Principal residue + 25% Mineral Fertilizer (3:1), (T6) = 50% Proportion of Principal residue + 50% Mineral Fertilizer (1:1), (T7) = 25% Proportion of Principal residue + 75% Mineral Fertilizer (1:3), (T8 = 75% Proportion of Principal residue + 25% Farmyard Manure natural; (T9) = 50% Proportion of Principal residue l + 50% Proportion of Principal residue; (T10) = 25% Proportion of Principal residue + 75% Farmyard Manure natural . The samples were dried at 65 ° C for 72 hours, after that it was grinded to determine the following parameters: electrical conductivity (EC) in relation to water, pH CaCl2 0.01 mol L-1, Moisture (%) of the samples removed 65ºC; Relation C/N; Content of Organic Matter (MOT) and total C. The results were submitted to analysis of variance and mean comparison test F at 5% probability, and where relevant treatment effects were evaluated by applying the polynomial regression models. The best model to fit the data was selected based on the significance degree of the coefficient of determination (R²). The data obtained showed that composting is a technique which may be effective in the treatment of waste from the oil industry, which requires the addition of inoculum and nutrients to provide the necessary conditions for microbial activity, the proportion of 25 RI% + 75% of LE. It was considered as a treatment which obtained an important result given the difficult to composting RI, that the period of 120 days was not enough to transform into compost humified and the addition of mineral fertilizer provided no significant effect. / Uma das formas de reduzir a concentração de resíduos é através da compostagem, sendo considerada como uma alternativa privilegiada de tratamento. Este trabalho teve como objetivo avaliar a compostabilidade de um resíduo industrial através do monitoramento de parâmetros químicos. O experimento foi conduzido na Faculdade de Ciências Agrárias, do Curso de Agronomia, localizada no Campus II, na Universidade do Oeste Paulista - UNOESTE, em Presidente Prudente/SP. Para os tratamentos, utilizou-se o resíduo industrial de uma empresa do setor de oleoquímica, devidamente caracterizado quimicamente antes da efetivação das misturas. Os tratamentos foram dispostos em pilhas de compostagem e caracterizados da seguinte forma: (T1) = Testemunha; (T2) = Proporção de 75% do Resíduo Principal + 25% de Lodo de Esgoto (ETE) (3:1); (T3) = Proporção de 50% do Resíduo Principal + 50% de Lodo de Esgoto (ETE) (1:1); (T4) = Proporção de 25% do Resíduo Principal + 75% de Lodo de Esgoto (ETE) (1:3); (T5) = Proporção de 75% do Resíduo Principal + 25% de Fertilizante Mineral (3:1); (T6) = Proporção de 50% do Resíduo Principal + 50% de Fertilizante Mineral (1:1); (T7) = Proporção de 25% do Resíduo Principal + 75% de Fertilizante Mineral (1:3); (T8) = Proporção de 75% do Resíduo Principal + 25% Esterco de Curral in natura; (T9) = Proporção de 50% do Resíduo Principal + 50% Esterco de Curral in natura; (T10) = Proporção de 25% do Resíduo Principal + 75% Esterco de Curral in natura. As amostras coletadas foram secas à 65 oC durante 72 horas e depois moídas para a determinação dos seguintes parâmetros: Condutividade elétrica (Ce) em água na relação; pH em CaCl2 0,01 mol L-1, Umidade (%) das amostras eliminada à 65oC; Relação C/N, Teor de Matéria Orgânica Total (MOT) e C total. Os resultados foram submetidos à análise de variância e ao teste de comparação de médias F ao nível de 5% de probabilidade e, quando pertinente os efeitos dos tratamentos foram avaliados aplicando-se os modelos de regressão polinomial. O melhor modelo para o ajuste dos dados foi escolhido em função do grau de significância do coeficiente de determinação (R2). De acordo com os dados obtidos verificou-se que a compostagem é uma técnica que poderá ser eficiente no tratamento do resíduo proveniente da indústria oleoquímica, sendo necessária, a adição de inoculantes e nutrientes que forneçam condições necessárias para a atividade microbiana; a proporção de 25% do RI + 75% de LE, foi considerada como um tratamento que obteve um resultado relevante diante da dificuldade de compostagem do RI; que o período de 120 dias não foi suficiente para transformação em composto humificado e a adição de fertilizante mineral não proporcionou efeito significativo.
206

Prospecção de componentes bioativos em resíduos do processamento do pescado visando a sustentabilidade da cadeia produtiva / Prospecting of bioactive components in the fish processing for the sustainability of the production chain

Lika Anbe 13 October 2011 (has links)
O resíduo gerado nas indústrias de processamento de pescado representa sérios problemas de poluição ambiental pela falta de destino adequado a este material. As espécies que alcançaram melhor rendimento produzem cerca de 30 a 40% da fração comestível na forma de filés. O ideal seria utilizar a matéria-prima em toda a sua extensão para obtenção de co-produtos, evitando a própria formação do resíduo. Elaborou-se a silagem ácida de pescado através do resíduo do processamento de sardinha (Sardinella brasiliensis) como forma de aproveitamento integral da matériaprima, constituídos por brânquias, vísceras, cabeças, escamas, espinhas dorsais e descartes de tecido musculares, incentivando a sustentabilidade desde a escolha do ácido e o aproveitamento de resíduos. A utilização do ácido cítrico (T1) como agente acidificador apresentou bons resultados em relação à mistura fórmico:propiônico (T2). Avaliou-se a estabilização das silagens, a aplicação da centrifugação (modelo 5810R, Eppendorf), sob rotação de 4840 x g; 0 ºC; 20min para obtenção das frações e o rendimento de cada parcela. Para T1 foram obtidos 17,1% de fração lipídica, 27,2% de fração aquosa (F1) e 55,7% de fração sedimentada. Para T2 foram obtidos 15,1% de fração lipídica, 31,8% de fração aquosa (F2) e 53,1% de fração sedimentada. A silagem ao ser fracionada se torna uma alternativa tecnológica com possível utilização em diferentes áreas de atuação, pois em sua porção aquosa (F), há presença de todos os aminoácidos essenciais. O aminoácido em maior concentração foi o ácido glutâmico em T1 e F1, sendo 12,3 e 11,53 g/100g de proteína, respectivamente. Para T2 o maior valor encontrado foi para glicina, da ordem de 11,94 g/100g de proteína; e para F2 o ácido glutâmico, 11,25 g/100g de proteína. Os resultados indicaram a possibilidade das frações aquosas serem empregadas como peptonas, devido aos teores de aminoácidos existentes serem semelhantes e/ou superiores aos presentes em produtos comerciais. Buscou-se quantificar o resíduo gerado em um dia de processamento em uma unidade de beneficiamento de tilápias (Oreochromis niloticus), bem como verificar o custo para o possível aproveitamento deste. Obteve-se 61,15% de resíduo, sendo que, 28,23%; 17,12%; 7,97% e 7,83% eram constituídos de carcaças, cabeças, vísceras e peles. Sugeriu-se para a unidade de processamento, o encaminhamento dos resíduos para produção de co-produtos, como forma de aumentar a sustentabilidade sócio-econômica e ambiental da unidade de processamento. / The waste generated in the fish processing industries poses serious environmental pollution problems due to lack of suitable target for this material. The species that produced better yield reached about 30 to 40% fraction in the form of edible fillets. The ideal would be to use raw material in its entirety to obtain co-products, avoiding the very formation of the residue. We developed the acid silage of fish waste throught the processing of sardines (Sardinella brasiliensis) as a way to use all the raw materials, consisting of gills, viscera, scales, spines and discharges of muscle tissue, encouraging sustainability from the choice of acid and waste recovery. The use of citric acid (T1) as sour agent showed good results in terms of mixing formic, propionic (T2). We evaluated the stabilization of the silage and the application of centrifugation (model 5810R, Eppendorf) under rotation 4840 x g, 0 ºC, 20min to obtain the fractions and yield of each plot. The silage when it becomes an alternative fractional technology with potential use in different areas, because in the watery portion (F), is presence all the essential amino acids. In T1 obtained 17.1% of total lipids, 27.2% of aqueous fraction (F1) and 55.7% sedimented fraction. T2 were obtained for 15.1% of total lipids, 31,8% aqueous fraction (F2) and 53.1% sedimentad fraction. The amino acid concentration was higher in glutamic acid in T1 and F1, being 12.30 and 11.53 g.100g-1 of protein, respectively. For T2 the highest value was found for glycine, the order of 11.94 g.100g-1 of protein; for F2 the content was found for glutamic acid, 11.25 g.100g-1 of protein. The results indicate the possibility of aqueous fractions were employed as peptones, due to the existing levels amino acid are similar and/or greater than those present in commercial products. We sought to quantify the waste generated in a day of processing a unit improvement of tilapia (Oreohromis niloticus) and check the cost for the possible use of this. We obtained 61.15% of waste, of which, 28.23%, 17.12%, 7.97% and 7.83% consisted of carcasses, heads, guts and skins. It has been suggested for the processing unit, the routing of the waste to produce co-products as a way to increase the socio-economic sustainability and environmental processing unit.
207

Imprégnation aux métaux et métalloïdes en population générale du Nord–Pas-de-Calais : niveaux, déterminants et liens avec le débit de filtration glomérulaire / Exposure to metals and metalloids in the general population of Northern France region : biological levels, determinants and links with the glomerular filtration rate

Tagne Fotso, Romuald 15 December 2016 (has links)
La biosurveillance humaine permet aujourd’hui d’évaluer notre exposition aux produits chimiques par la mesure soit des substances elles-mêmes, soit de leurs métabolites ou marqueurs d'effets sur la santé, à partir des fluides corporels ou des tissus. Les informations recueillies dans le cadre d’enquêtes épidémiologiques renseignent sur l'exposition humaine et constituent des bases précieuses dans la recherche des relations exposition-réponse chez les humains. Les travaux de cette thèse s’inscrivent dans le cadre de l’enquête transversale IMePoGe conduite entre 2008-2010 dans la région Nord–Pas-de-Calais (au nord de la France), incluant 2000 résidents adultes âgés de 20 à 59 ans, et visant à quantifier les niveaux d’imprégnation de la population à 14 métaux et métalloïdes (aluminium, antimoine, arsenic total, béryllium, cadmium, cobalt, chrome, mercure, manganèse, nickel, plomb, thallium, vanadium, zinc) choisis pour leurs effets toxiques et la fréquence de l’exposition professionnelle et environnementale. Les objectifs spécifiques de cette thèse étaient, tout en portant une attention particulière au plomb et au cadmium, deux métaux néphrotoxiques connus dans la littérature : i) d’établir la distribution de l’imprégnation aux métaux et métalloïdes dans la population du Nord de la France et de comparer le niveau régional d’imprégnation avec les données nationales et internationales ; ii) d’identifier les facteurs majeurs de variation de l’imprégnation et les sources d’exposition au plomb et au cadmium dans la population générale ; iii) d’étudier la relation entre la variation du débit de filtration glomérulaire et les niveaux d’imprégnation aux métaux. Globalement, les concentrations sanguines et urinaires de la plupart des métaux et métalloïdes étaient plus élevées que celles rapportées dans l’enquête nationale nutrition santé conduite sur la même période dans la population française, à l’exception du vanadium urinaire et du plomb sanguin. La plombémie moyenne régionale (moyenne géométrique) était de 18,8 μg/L. De nombreuses sources d’exposition au plomb existaient dans la population et étaient à la fois d’origine professionnelle, environnementale et alimentaire. Pour ce qui est du cadmium, le tabagisme se présentait comme la principale source d’exposition récente ou chronique au métal : la cadmiémie moyenne, reflet de l’exposition récente, était de 0,39 μg/L et passait de 0,26 μg/L chez les non-fumeurs à 0,84 μg/L chez les fumeurs ; la cadmiurie moyenne, reflet de l’exposition chronique, était de 0,37 μg/L (0,33 μg/g créatinine) et passait de 0,33 μg/L (0,29 μg/g créatinine) chez les non-fumeurs à 0,46 μg/L (0.37 μg/g créatinine) chez les fumeurs. Enfin, dans le cadre de l’étude de la relation entre l’imprégnation aux métaux et le débit de filtration glomérulaire, notre étude a montré que la prise en compte de la co-exposition à d’autres métaux et métalloïdes potentiellement néphrotoxiques bouleversait considérablement les associations antérieures jusqu’ici rapportées spécifiquement avec le plomb et le cadmium, dans le cadre de faibles niveaux d’imprégnation en population générale. / Human Biomonitoring allows us to evaluate our exposure to chemicals by measuring substances themselves or their metabolites or markers of health effects, from body fluids or tissues. The information collected through epidemiological surveys provide information on human exposure and are valuable databases in the research of exposure-response relationships in humans. This thesis is part of the cross-sectional IMePoGe survey conducted between 2008-2010 in the Nord–Pas-de-Calais region (in northern France), including 2,000 adult residents aged 20 to 59 years old, and aimed to quantify the impregnation levels of the population to 14 metals and metalloids (aluminum, antimony, total arsenic, beryllium, cadmium, cobalt, chromium, mercury, manganese, nickel, lead, thallium, vanadium, zinc) chosen for their toxic effects and the frequency of occupational and environmental exposure. The specific objectives of this thesis were, which a special interest for lead and cadmium, two nephrotoxic metals known in the literature: i) to establish the distribution of impregnation metals into the northern population of France and compare the exposure regional level to metals and metalloids with the national and international data; ii) to identify the major factors of variation of the impregnation and the sources of exposure to lead and cadmium in the general population; iii) to study the relationship between the change in glomerular filtration rate and the impregnation levels to metals. Overall, blood and urinary concentrations of most metals and metalloids were higher than those found in the national nutritional health survey conducted during the same period in the French population, with the exception of urinary vanadium and blood lead. The regional mean of blood lead level (geometric mean) was 18.8 μg/L. Several sources of lead exposure existed in the population and were link to the occupational, environmental and consumption parameters. Regarding cadmium, smoking was the main source of recent or chronic exposure to metal: the geometric mean of blood cadmium, reflecting a recent exposure, was 0.39 μg/L and increased from 0.26 μg/L in non-smokers to 0.84 μg/L in smokers; the geometric mean of urinary cadmium, reflecting the chronic exposure, was 0.37 μg/L (0.33 μg/g creatinine) and increased from 0.33 μg/L (0.29 μg/g creatinine) in non-smokers to 0.46 μg/L (0.37 μg/g creatinine) in smokers. Finally, as part of the study of the relationship between the metal levels and the glomerular filtration rate, our study showed that taking into account the multiple exposure to the other potentially nephrotoxic metals and metalloids upset considerably the previous associations specifically reported with lead and cadmium, in the context of low levels exposure in the general population.
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In vitro bioassays as tools for evaluating toxicity of acidic drainage from a coal mine in Mpumalanga, South Africa

Iji, Oluwafikemi Temitayo January 2016 (has links)
Coal mining and coal utilization in Mpumalanga have increased over the years due to national reliance on coal as a source of power generation. In general, this has caused significant deterioration of water quality wherever streams are impacted by acid mine drainage (AMD). The aim of this research was to assess the use of in vitro bioassays as a complement to, or potential future replacement of, waste effluent testing in whole animals from AMD impacted watersheds subjected to passive and active treatment, correlating observed changes with water chemistry analysis. To accomplish this goal, water samples were collected and in vitro bioassays carried out to investigate generation of reactive oxygen species by the water samples and cytotoxicity against Vero kidney cells, C3A liver cells and trout RTgill-W1 cells. Primary fish gill cultures were established and used as sensitive in vitro models for assessing possible contaminants in water, measuring the induction of cytochrome P450 (CYP) 1A and resultant increase in 7-ethoxyresorufin-o-deethylase activity as a potential biomarker in fish gill cells exposed to polycyclic aromatic hydrocarbons. The genotoxic potential of AMD water on commercially available cell lines was also determined. / The study site was an impacted stream located downstream of a coal mine discharge point whose effluent flowed away from the mine. Water chemistry results suggested high AMD impact evidenced by acidity, elevated sulphates, increased conductivity and presence of heavy metals. Al, Fe, Zn, Mn and Si were the major metals of potential concern in the AMD impacted stream; sulphates and major ions like Ca, K, Na and Mg were present at levels above target water quality range (TWQR) for effluents in receiving stream. The AMD impacted stream caused increased generation of reactive oxygen species (ROS) detectable in vitro in selected cell lines (Vero, C3A and RTgill-W1 cell lines), an indication of oxidative stress. In-stream, active treatment with caustic soda was efficient at reducing metal burden, with subsequent reduction in ROS generation in fish gill cell lines. For in vitro cytotoxicity tests, passive and active treated AMD water was cytotoxic to cell lines (Vero and RTgill-W1), with the fish RTgill-W1 cells exhibiting greater sensitivity compared to the mammalian Vero cells. Mitochondria played a larger role in observed loss in cellular viability (increased vacuolization, mitochondrial membrane swelling and damage), which was detected using mitochondrial specific stains, and by transmission electron microscopy (TEM). Increased dose- dependent cytotoxicity was observed in the fish gill and mammalian cell lines. Cells exposed to water samples (AMD and reference sites) revealed significant differences (p < vi 0.05) between the AMD impacted watershed and a relatively pristine site (reference site) where exposure to the same cells maintained approximately 100% viability at all concentrations for up to 72h exposure. The observed differences in effect in this study demonstrate that the effluent from the coal mine negatively impacted surface water quality, resulting in toxicity to cell lines, therefore creating an environment that would not be conducive for the survival of biological aquatic communities and potentially of concern for downstream human end users. / The induction of cytochrome P450 (CYP) 1A and resultant increase in 7- ethoxyresorufin-o-deethylase activity in primary fish gill cultures exposed to polycyclic aromatic hydrocarbons B[a]P, a known AhR agonist contaminant associated with coal mining, showed that there was as increase in EROD activity which was not observed using the RTgill-W1 cell lines. Gill epithelial cells isolated from the gills of Tilapia fish (Oreochromis mossambicus) bear close similarities to fish gills in vivo and their capacity to respond to the presence of AhR indicates that they may serve as a simple, cost-effect screening tool for assessing PAHs and dioxin-like compounds in fresh water. / For genotoxicity evaluation, the Ames test performed without metabolic activation using bacterium Salmonella typhimurium TA98 and TA100 strains revealed no indication of genotoxic activity in any of the water samples. Genotoxicity assessment of all water samples using the comet assay however exposed DNA damage to Vero and RTgill-W1 cell lines. A significant reduction in DNA damage was observed following active treatment. The results suggest that neither treatment technologies employed were efficient at removing all potential genotoxicants so further improvements are required. The comet assay proved sensitive enough to detect genotoxicity in reference water samples despite no known untoward effluent inputs at the site, suggesting potential for this assay to be integrated into an environmental monitoring framework. / The results obtained support the use of in vitro bioassays for evaluating toxicity of industrial effluent through biological responses in test systems elicited following exposure, improving ability to detect AMD polluted water. This could be beneficial when assessing the degree and extent of impact of AMD in natural water sources, and the possible environmental impact resulting from hazardous elements present in effluent water. In conclusion, these results suggest that in vitro techniques involving cell lines and primary cultures from fish may serve vii as simple, rapid and cost-effective tools for assessing risk and potential toxic effects of contaminants in AMD waters. / Thesis (PhD)--University of Pretoria, 2016. / The National Research Foundation / Department of Paraclinical Sciences (University of Pretoria) / Schlumberger Stichting Fund, Netherlands / Paraclinical Sciences / PhD / Unrestricted
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Ecodynamique des composés poly- et perfluoroalkylés dans les écosystèmes aquatiques / Environmental fate of poly- and perfluoroalkyl compounds in aquatic ecosystems

Munoz, Gabriel 16 December 2015 (has links)
Les tensioactifs poly- et perfluoroalkylés (PFAS) sont des composés d’origine anthropique produits à partir des années 1950 et qui sont désormais considérés comme des polluants ubiquistes. La première partie de ce travail a consisté à optimiser et valider des procédures pour l’analyse ultra-trace des PFAS. Ces méthodes ont ensuite été utilisées afin d’apporter de nouveaux éléments de réponse sur l’occurrence et la dynamique des PFAS dans les environnements aquatiques. Une attention particulière a été accordée aux valeurs censurées (<LD). Dans les eaux de surface et les sédiments, à l’échelle nationale, le perfluorooctane sulfonate (PFOS) s’est avéré prédominant parmi les acides perfluoroalkylés (PFAA) considérés ; la fraction organique du sédiment est apparue un facteur de contrôle clé des teneurs sédimentaires. L’utilisation des cartes auto-organisatrices de Kohonen a facilité la synthèse des résultats et les comparaisons entre sites. A une échelle plus locale, ces travaux ont permis de cartographier la contamination sédimentaire d’un estuaire macrotidal et d’étudier les facteurs de contrôle de leur distribution. La dynamique spatio-temporelle des PFAS et leur transfert aux premiers maillons trophiques ont été évalués en milieu fluvial urbain (la Seine) et en milieu estuarien (la Gironde). La détermination des facteurs d’amplification trophique en estuaire de Gironde confirme le caractère bioamplifiable du PFOS et de certains PFAA à longue chaîne. Le dernier axe de ces travaux concernait la recherche de PFAS d’intérêt émergent zwittérioniques et cationiques ; des résultats préliminaires semblent dissiper les inquiétudes concernant leur potentiel de bioaccumulation. / Poly- and perfluoroalkyl surfactants (PFAS) are anthropogenic compounds that have been used sincethe 1950s in a variety of applications and that have emerged as ubiquitously distributed contaminants.The first aim of this work was to optimize and validate analytical procedures for the trace-leveldetermination of PFAS. These methods were then applied to various sets of environmental samples,providing new elements to document the occurrence and environmental fate of PFAS in aquaticecosystems. In terms of statistical analyses, a special care has been devoted to incorporate nondetects(data <LOD). In French surface waters and sediments, perfluorooctane sulfonate (PFOS) wasthe prevailing perfluoroalkylated acid (PFAA); sediment organic carbon fraction was a key controllingfactor of PFAS sedimentary levels. Kohonen self-organizing maps were used to highlight similaritiesand differences between sites, providing evidence for distinctive features, sometimes at watershedscale. A mapping of PFAS in sediments was established in a macrotidal estuary, along with theirpartitioning behavior in the water column. The spatio-temporal dynamics of PFAS and transfer to thefirst trophic levels were investigated in an urban freshwater hydrosystem (the Seine River) and in anestuarine environment (Gironde estuary). In the Gironde estuary, trophic magnification factors (TMF)were significantly >1 for PFOS and several long-chain PFAA, providing new evidence for theirbiomagnification. The last theme addressed in this work was the analysis of newly-identified cationicand zwitterionic PFAS ; preliminary evidence seem to dispel concerns about the bioaccumulationpotential of the latter.
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Small and Medium Enterprises' Profitability Elements in Green Energy Transactions

Great, Humphrey Edereka 01 January 2015 (has links)
As the primary drivers of Nigeria's economy, small and medium scale enterprise (SME) leaders rely on standby generators for sustainable business operation. Because of this reliance, over 56% of the SMEs operate far below capacity from the effects of power shortages. Guided by the strategic contingency theory, this study explored the profitability strategies of business leaders faced with electricity disruptions within Abuja Federal Capital Territory while adopting corporate social responsibility (CSR) and green practices. Data collection was through face-to-face semistructured interviews using open-ended questions. Participants consisted of 12 business leaders selected from 4 SME categories within Abuja that have imbibed CSR and green practices successfully or were in the process of doing so. The data analysis process involved labeling and coding all data that arose from participant interviews using the modified van Kaam method to identify dominant themes. Data coding and analysis led to the identification of 12 predominant meta-themes, including innovativeness for sustainable green business, strategy challenges and how they were addressed, and the power disruption impact on the effectiveness of CSR and organizational profitability. Findings from this study might contribute to new knowledge and success insights for SME business leaders faced with power shortages, CSR shortages, and losses in Abuja. Social change might result as SME business leaders embrace CSR practices with new environmentally friendly tenets, make sustainable profits, employ more people, and dedicate part of the profits to social services to benefit citizens of Abuja and Nigeria.

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