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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.
21

Palatabilidade, qualidade de fezes e digestibilidade aparente de equinos submetidos a dietas com diferentes níveis de inclusão de casca de soja / Palatability, apparent digestibility and fecal quality of horses fed diets with different levels of inclusion of soybean hulls

Kabe, Assuka Marina Godoy 01 February 2013 (has links)
Com o objetivo de avaliar o efeito da inclusão de níveis crescentes de casca de soja (0, 7, 14, 21 e 28%) no concentrado para equinos, foram realizados dois experimentos, ambos conduzidos no Setor de Equideocultura da Prefeitura do Campus de Pirassununga da Faculdade de Zootecnia e Engenharia de Alimentos. O primeiro experimento consistiu em ensaio de palatabilidade, composto pela análise conjuntas das variáveis: primeira ação (ação realizada pelo animal assim que entrou em contato com os concentrados, cheirou ou comeu), primeira escolha (primeiro concentrado efetivamente ingerido pelo animal), e razão de ingestão (quantidade de cada um dos concentrados ingerida em relação ao total consumido, em um período de 3 minutos). Para tanto, foram utilizados dez equinos, em delineamento inteiramente casualisado. Foi observado efeito (p<0,05) para a primeira ação, sendo que 37,19% dos animais cheiraram e 62,81% dos animais ingeriram os concentrados. Já, para as variáveis primeira escolha e razão de ingestão, não foi observada diferença (p>0,05), demonstrando-se que a preferência e consumo de cada um dos concentrados foram semelhantes. No segundo experimento realizou-se ensaio de digestibilidade aparente dos nutrientes e características físico-químicas das fezes. Cinco éguas dispostas em delineamento quadrado latino 5x5, foram utilizadas. A dieta utilizada apresentou 60% de volumoso (feno de Coast-Cross) e 40% de concentrado, visando atender as exigências nutricionais da categoria animal. Realizaram-se análises para determinação dos teores de matéria seca (MS), matéria mineral (MM), matéria orgânica (MO), extrato etéreo (EE) e proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), hemicelulose (HC) e energia Bruta (EB), nutrientes para os quais foi determinada a digestibilidade aparente. As características físico químicas das fezes foram analisadas avaliando-se as concentrações de ácidos graxos de cadeia curta (AGCC) o pH, a capacidade tamponante a 5 e a 6, e características de cor e consistência das fezes. Não foi observado efeito (p>0,05) dos níveis de inclusão sobre os coeficientes de digestibilidade dos nutrientes, bem como não houve efeito (p>0,05) sobre as características físico-químicas das fezes. Os Coeficientes de digestibilidade dos nutrientes encontram-se dentro dos valores preconizados pela literatura, sendo os coeficientes médios de digestibilidade aparente de MS, MO, FDN, FDA, HC, PB, EE, EB, respectivamente de: 53,67; 54,71; 47,04; 39,50;54,08; 66,74 e 83,73%. O pH médio observado foi de 6,4 e a capacidade tamponante ao pH 5 (CT5) e capacidade tamponante ao ph 6 (CT6) médias foram respectivamente de 14,09 e 4,41 (mmol/l). Para as características físicas das fezes, cor e consistência, 100% das fezes apresentaram-se esverdeadas e 90% normais, evidenciando que não houve alteração deletéria no intestino grosso dos equinos. A casca de soja pode ser incluída em dietas para equinos, em níveis de até 28% do concentrado, sem causar efeito deletério sobre a digestibilidade dos nutrientes da dieta e sobre a palatabilidade dos concentrados, além de não apresentam efeito deletério sobre as características físico-químicas das fezes, sugerindo manutenção da saúde do trato digestório. / Aiming to evaluate the effect of increasing levels of soybean hulls (0, 7, 14, 21 and 28%) in horses concentrate, two experiments were conducted in the Equideocultura Sector of Faculdade de Zootecnia e Engenharia de Alimentos City Hall. The first experiment was the palatability test, composed by the joint analysis of variables: first action (action performed by the animal as soon as it came in contacted with the concentrates: smelled or ate), first choice (first concentrate effectively ingested by the animal), and ratio intake (amount of each one concentrate ingested in the total consumed, over a period of 3 minutes). Thus, ten horses were used in a completely randomized test. Effect was observed (p<0.05) for the first action, with 37.19% of the animals sniffed and 62.81% of the animals ingested the concentrates. As for the variables: first choice and ratio of intake, there was no difference (p>0.05), demonstrating that the preference and consumption of each one of the concentrates were similar. The second experiment conducted was the nutrient digestibility test and physicochemical characteristics of the feaces. Five mares were used, arranged in 5x5 Latin Square design. The diet had 60% roughage (Coast Cross hay) and 40% concentrate, to meet the nutritional requirements of the animal category. Analysis were made to determine the dry matter (DM), mineral matter (MM), organic matter ( OM), ether extract (EE) and crude protein (CP), neutral detergent fiber (NDF) detergent fiber acid (ADF), hemicellulose (HC) and gross energy (GE), and the apparent digestibility was determined for each nutrient. The physicochemical characteristics of feces were analyzed by evaluating the short chain fatty acids (SCFA) concentrations, pH, buffering capacity (BC) at 5 and 6, and color and faeces consistency. There was no effect (p>0.05) for the inclusion level on the nutrients digestibility, and there was no effect (p>0.05) on the feaces physicochemical characteristics. The digestibility coefficients of nutrients are within the levels recommended by the literature, and the apparent digestibility of DM, OM, NDF, ADF, HC, CP, EE, EB, were: 53.67; 54.71; 47.04, 39.50, 54.08, 66.74 and 83.73%, respectively. The average pH observed was 6.4 and the BC5 and BC6 medium were 14.09 and 4.41 (mmol/l) respectively. For the feaces physical characteristics, color and consistency of the feaces, 100% showed green color and 90% was normal, indicating no deleterious changes in the equine large intestine. Soybean hulls can be included in the horses diet at levels up to 28% of the concentrate, without causing deleterious effect on the nutrients digestibility and the concentrates palatability, and there wasn\'t deleterious effect on the feaces physicochemical characteristics, suggesting maintenance of the digestive tract healthy.
22

Efeito hipolipemiante e antioxidante de subprodutos da uva em hamsters / Hypolipidemic and antioxidant effects of grape processing byproducts in hamsters

Ishimoto, Emilia Yasuko 13 May 2008 (has links)
Introdução: Recentes pesquisas têm indicado o enorme potencial de certas substâncias alimentares, como polifenóis antioxidantes e fibras na redução de riscos de doenças crônicas. O bagaço de uva, subproduto do processamento de vinhos e sucos, representa uma ótima fonte de fibras e antioxidantes naturais de baixo custo. Objetivo: Avaliar o potencial hipolipemiante, antioxidante e sensorial de subprodutos do processamento do vinho e do suco. Métodos: Para avaliar a capacidade antioxidante in vitro, foi utilizado o método do DPPH. O potencial antioxidante e hipolipemiante in vivo foi avaliado mediante ensaio biológico, no qual sessenta hamsters foram divididos em seis grupos diferenciados pelas dietas: controle, hiperlipemiante, extrato de bagaço do vinho (BV), extrato de bagaço do suco (BS), suplementada com BV e suplementada com BS. Amostras de sangue e fígado foram coletadas após 4 semanas de experimento para avaliação do perfil lipídico, capacidade de inibição da oxidação de LDL-colesterol (LDL-c) e atividade das enzimas antioxidantes superóxido dismutase (SOD), catalase (CAT) e glutationa peroxidase (GPx). Para a avaliação sensorial, foram desenvolvidos sorbet e picolé de BV e BS, cujos atributos sensoriais foram avaliados por 43 pessoas aplicando-se o método afetivo de escala hedônica de 9 pontos. Resultados: Extratos de BV e BS apresentaram uma expressiva capacidade antioxidante in vitro. No modelo animal, os grupos tratados com BV e BS apresentaram uma melhora significativa do perfil lipídico e da atividade da enzima CAT, em relação aos grupos controle e hipercolesterolêmico (p<0,05). Com relação aos valores de SOD, GPx e inibição da oxidação de LDL-c, observou-se melhores resultados em relação ao grupo hipercolesterolêmico, embora não significativamente em todos os grupos tratados. Na análise sensorial, somente o picolé de BV não preencheu totalmente os requisitos de aceitação. Conclusão: Os subprodutos de ambas as espécies de uva apresentaram potencial biológico e sensorial para serem utilizados como ingredientes funcionais. / Introduction: Recent studies have shown the great potential of certain food components such as antioxidant polyphenols and fiber in reducing the risk of chronic diseases. Grape pomace, a wine and juice processing byproduct, is a low cost material and a very good source of fiber and natural antioxidants. Objectives: To evaluate the hypolipidemic, antioxidant and sensory potential of wine and grape byproducts. Methods: To evaluate the in vitro antioxidant capacity, the DPPH method was used. The in vivo antioxidant and hypolipidemic potential was evaluated through an animal model, in which sixty hamsters were divided into six groups according to their diets: control, hyperlipidemic, wine pomace (WP) extract, juice pomace (JP) extract, WP supplemented diet and JP supplemented diet. Samples of blood and liver were collected after a 4-week experimental period to evaluate the lipid profile, ability to inhibit the LDL-cholesterol (LDL-c) oxidation and antioxidant activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) enzymes. For the sensory evaluation, BV and BS sorbet and popsicle were developed, and the sensory attributes were evaluated by 43 tasters according to a 9- point affective hedonic scale. Results: WP and JP extracts showed a very good in vitro antioxidant capacity. In the animal model, both WP and JP treated groups presented a significant improvement in the lipid profile and CAT enzyme antioxidant activity in comparison to hypercholesterolemic and control groups (p <0.05). Regarding the values of SOD, GPx and inhibition of LDL-c oxidation, there values were better when compared to hypercholesterolemic group, even though they were not significant in all treated groups. In the sensory evaluation, only the BV popsicle was not fully accepted. Conclusion: Both grapes byproducts showed a biological and sensory potential to be used as functional ingredients.
23

Formação de subprodutos do estrona e 17\'beta\'-estradiol na oxidação utilizando cloro e o ozônio em água / Formation of byproducts of estrone and 17\'beta\'-estradiol oxidation using chlorine and ozone in water

Pereira, Renata de Oliveira 18 February 2011 (has links)
A poluição dos corpos de água é cada vez maior devido ao lançamento de efluentes, esgotamento sanitário e disposição inadequada de resíduos sólidos. Esse fato causa grande preocupação à comunidade científica, pois à poluição associam-se riscos à saúde causado por poluentes bioativos, compostos químicos orgânicos persistentes e outros compostos que poderiam estar presentes na água. Dentre as substâncias que causam risco à saúde se destacam os desreguladores endócrinos, que são compostos químicos exógenos que interferem na atividade hormonal. Os sistemas de tratamento de água convencionais não removem alguns compostos, tais como pesticidas e hormônios, os quais deveriam ser removidos. O uso do ozônio e cloro vem sendo reportado para tal finalidade, pois atuam como oxidantes que são capazes de oxidar compostos orgânicos, além de serem poderosos desinfetantes. Portanto, o objetivo deste estudo foi avaliar a eliminação e/ou redução dos desreguladores endócrinos - DE em estações de tratamento de água com o uso do ozônio e do cloro. Aliado ao estudo, avaliar qual será a eficiência de remoção de organismos indicadores nas doses utilizadas para oxidação de DE (Coliformes Totais e E.coli) e avaliar a ecotoxicidade em peixes de amostras cloradas contendo 17\'beta\'-estradiol. O cloro e o ozônio foram capazes de remover eficientemente estrona (E1) e 17\'beta\'-estradiol (E2) de águas, contudo a eficiência de remoção diminui em concentrações na ordem de ng/L, necessitando-se de altas doses de ozônio e cloro para a completa remoção dos hormônios estudados. Tanto o cloro como o ozônio foram eficientes na inativação de organismos indicadores nas doses comumente utilizadas em ETAs e nas doses requeridas para a remoção dos contaminantes estudados. Amostras contendo E2 após serem cloradas apresentaram toxicidade crônica a peixes da espécie Danio rerio, o efeito estrogênico foi observado principalmente em machos. Foi necessário uma dose de ozônio de 0,95 e 3,8 mg/L para a remoção de 93 e 98% de E2 e E1 respectivamente (Co = 100 ng/L). Considerando o cloro como oxidante após a aplicação de 1,5 mg/L com tempo de contato de 24 h chegou-se a uma remoção de 99,6 e 97,5% para o E2 e E1 respectivamente (Co = 500 ng/L). Tão importante quanto remover o estrona e o 17\'beta\'-estradiol foi verificar e identificar quais foram os subprodutos formados após a oxidação dos mesmos. Foram identificados vários subprodutos tanto utilizando a degradação por meio do cloro como do ozônio. Alguns destes compostos identificados foram persistentes e recalcitrantes. Para o ozônio a completa remoção foi atingida após 10 mg/L de \'O IND.3\' e 16 mg/L de \'O IND.3\' para os subprodutos do E1 e E2 respectivamente. Considerando o cloro mesmo após um tempo de contato de 16 dias, havia ainda subprodutos da degradação na água. / The pollution of water bodies is increasing due to the release of effluents, sewage and inadequate solid waste disposal. This fact causes great concern to the scientific community, because pollution are associated with health risks caused by pollutants of bioactive compounds and other persistent organic compounds that could be present in water. Among the substances that can cause health risks are the endocrine disrupters, which are exogenous chemicals that interfere with hormonal activity. The conventional water treatment systems does not remove certain compounds, such as pesticides and hormones, which should be removed. The use of ozone and chlorine has been reported for this purpose because it acts as an oxidant that can oxidize organic compounds, and addicionally are powerful disinfectants. Therefore, the aim of this study was the elimination and/or reduction of endocrine disrupters during the water treatment using ozone and chlorine. Allied to the study, evaluate the efficiency of indicator organisms removal in the doses used for the oxidation of endocrine disrupters (coliform and E.coli) and assess the ecotoxicity of fish in chlorinated samples containing 17\'beta\'- estradiol. Chlorine and ozone were able to efficiently remove estrone (E1) and 17\'beta\'-estradiol (E2) of water, but the removal efficiency decreases at concentrations in the ng/L. Complete removal of the hormones was reach with high doses of ozone and chlorine. Both chlorine and ozone were effective in the inactivation of indicator organisms at commonly doses used in water treatment plants and in the doses required for the removal of the pollutants studied. Samples containing chlorinated E2 had chronic toxicity to fish Danio rerio, the estrogenic effect was observed mainly in males, females in some groups estrogenic effect was not observed. The dose of ozone necessary for the removal of 93 and 98% of E1 and E2 (Co = 100 ng/L) were 0.95 and 3.8 mg/L, respectively. The application of 1.5 mg/L of chlorine with a contact time of 24 h achieved removal of 99.6 and 97.5% for E1 and E2 respectively (Co = 500 ng/L) . As important as removing estrone and 17\'beta\'-estradiol was to verify and identify which were the byproducts formed after oxidation. Several byproducts were identified by the degradation using chlorine and ozone. Some of these compounds were identified to be persistent and recalcitrant. The ozone dose required to the complete removal of the byproducts was achieved after 10 mg/L \'O IND.3\' and 16 mg/L \'O IND.3\' for the byproducts of E1 and E2 respectively. The byproducts of chlorine even after a contact time of 16 days persisted in the water.
24

Efeito da variação da qualidade do efluente final produzido em sistema de lodos ativados convencional no processo de desinfecção. / Effects of the quality variability of activated studge final effluent on the desinfection process.

Marta Regina Inoue 24 November 2009 (has links)
A operação de uma estação de tratamento de esgotos pode apresentar várias alternativas para condução da desinfecção do efluente final, devendo-se levar em conta os seus custos, benefício, facilidade de instalação, operação, disponibilidade no mercado e as propriedades de cada agente desinfetante. Dentre os diferentes agentes desinfetantes que podem ser empregados o cloro é o que mais tem sido utilizado em função do seu baixo custo, facilidade de operação e também pelos diversos estudos realizados e consolidados com esse agente desinfetante. Desta forma, este trabalho estudou o efeito da variação da qualidade do efluente final produzido em sistemas de lodos ativados convencional no processo de desinfecção utilizando cloro na forma de hipoclorito de sódio. O efluente final empregado na condução dos ensaios experimentais foi gerado pela ETE Jesus Netto, sendo que a instalação piloto consistiu em um tanque de contato com dimensões de 3 metros de comprimento, 3 metros de largura e 0,8 m de altura útil, perfazendo um volume útil igual a 7,2 m³. A dosagem aplicada de agente oxidante foi de 5 mgCl2/L e os tempos de contato avaliados foram de 10 minutos a 30 minutos. Nos ensaios realizados houve a formação de cloraminas, provenientes da nitrificação parcial do processo de lodos ativados da ETE, e em alguns casos também foi observada a presença de cloro residual livre na saída do tanque de contato. Para ensaios de avaliação microbiológica do efluente desinfetado foram observados valores de remoção acima de 5 (expresso como log No/N) para coliformes totais para um tempo de detenção hidráulico superior a 30 minutos e remoção acima de 4 (expresso como log No/N) de coliformes termotolerantes para tempos de detenção hidráulico superior a 20 minutos. ) Para os parâmetros físico-químicos cor aparente, pH, turbidez, nitrogênio amoniacal, demanda química de oxigênio, carbono orgânico total e sólidos suspensos totais não foram observados alterações significativas no afluente e efluente do tanque de contato do processo de desinfecção. Para valores de DBO5,20 inferiores a 20 mg/L e valores de sólidos suspensos totais inferiores a 30 mg/L, não foram observados efeitos no comportamento do processo de desinfecção nos efluentes da ETE Jesus Netto. Os ensaios realizados permitiram avaliar a formação de subprodutos da desinfecção, sendo que os valores de trihalometanos no efluente da água na saída do tanque de contato resultaram abaixo de 10 µg/L. A toxicidade no efluente dos sistemas de lodos ativados convencional foi não detectável. Os bioensaios indicaram que a presença de cloro eleva a toxicidade aguda em Daphnia similis e cloração seguida de descloração produz efluentes sem toxicidade. / The operation of a Wastewater Treatment Plant (WWTP) may present several alternatives with regard to carrying out the final effluent disinfection. One must take into account cost-benefit criteria, easiness of installation and operation, availability in the disinfection market and the properties of each alternative disinfectant. Among the available disinfectant agents that can be put to use, chlorine has been the most widely utilized because of its low cost, easiness of handling and also due to the existing several studies on chlorine disinfection. In this way, this work the effects of quality variability of the final effluent from a conventional activated sludge plant (CASP) on the disinfection process with sodium hypochloride. The final effluent was generated at the Jesus Netto CASP and the pilot scale unit utilized in this work was a contact tank 3 meters long, 3 meters wide and a net depth of 0,8 meters, leading to a net volume of 7.2 m³. The applied free chlorine dose was 5 mg Cl2/L and the utilized contact times were 10 and 30 minutes. During the experimental runs there was formation of chloramines from partial nitrification in the Jesus Netto CASP. In some cases the presence of a free chlorine residual at the outlet of the contact tank was observed. Regarding microbiological evaluation of the disinfected plant effluent, removal efficiencies above 5 logs (expressed as log No/N) were observed for total coliforms with a contact time above 30 minutes and alsothermo tolerant coliform removal efficiencies above 4 logs for hydraulic residence times above 20 minutes. Regarding the physical-chemical variables apparent color, pH, turbidity, ammonia nitrogen, chemical oxygen demand, total organic carbon and total suspended solids, no significant changes in the affluent and effluent of the contact tank were observed. ) For BOD5,20 values below 20 mg/L and TSS values below 30 mg/L, no effects on the tested disinfection process for the Jesus Netto CASP were observed. The experimental runs allowed the evaluation of disinfection byproduct formation. THM levels in the contact tank effluent were below 10 µg/L. No toxicity was detected in the Jesus Netto CASP effluent. Bioassays were conducted and indicated that the presence of chlorine increased the acute toxicity level as evaluated with Daphnia similis and also that CASP effluent chlorination followed by dechlorination produced a disinfected effluent without toxicity.
25

Avaliação de biomarcadores da exposição humana à fumonisina B1 nos alimentos em municípios dos estados de São Paulo e Santa Catarina, Brasil / Evaluation of biomarkers of human exposure to dietary fumonisin B1 in cities from São Paulo and Santa Catarina states, Brazil

Bordin, Keliani 25 February 2015 (has links)
A fumonisina B1 (FB1) e uma micotoxina produzida pelo metabolismo secundário de espécies de Fusarium, principalmente F. verticillioides e F. proliferatum, os quais contaminam diversos alimentos antes e apos o processamento, sobretudo o milho e derivados, gerando graves problemas para a Saúde Pública e a qualidade dos alimentos. O objetivo deste trabalho foi avaliar a exposição humana a FB1 presente nos alimentos através da estimativa de ingestão da toxina na dieta e da análise de diferentes biomarcadores presentes em amostras de sangue, urina e cabelo. Além disso, foram investigados os efeitos da toxina através da avaliação de ácido fólico presentes em alimentos e em soro, e os níveis de uréia e creatinina presentes em soro. O estudo foi realizado em dois municípios dos Estados de São Paulo e Santa Catarina, cujos respectivos voluntários foram categorizados como de baixo consumo de derivados de milho (Grupo A, voluntários de Pirassununga/SP) e de alto consumo de derivados de milho (Grupo B, voluntários de Erval Velho/SC). As amostras de alimentos do Grupo A (Pirassununga/SP) foram fornecidas pelos voluntários (n=100) nos meses de Junho/2011, Setembro/2011, Dezembro/2011 e Marco/2012. Os voluntários do Grupo B (Erval Velho/SC) (n=20) forneceram amostras de alimentos no mês de Abril/2012. Em cada grupo, uma lista com 20 alimentos a base de milho foi entregue aos voluntários, para fornecimento de amostras daqueles disponíveis em suas respectivas residências em cada mês de amostragem, totalizando 122 amostras de derivados de milho no Grupo A e 17 amostras no Grupo B coletadas durante o estudo. Adicionalmente, aplicou-se um Questionário de Frequência Alimentar (QFA) e um Inquérito Recordatório de 24 horas (QIR - 24 h) no momento das coletas de amostras. Em cada mês de amostragem de alimentos, foram coletadas amostras de sangue, urina (somente Grupo A) e cabelo dos voluntários, sendo as amostras armazenadas a -20ºC (urina e cabelo) ou -80ºC (sangue) até o momento das análises. As amostras de alimentos foram submetidas a análise de FB1, sendo que as de farinha de milho foram também analisadas quanto ao teor de ácido fólico. Ambas as análises foram feitas através de cromatografia líquida de alta eficiência (CLAE). Em soro, foram avaliadas a relação esfinganina/esfingosina (Sa/So), resíduos de FB1, ácido fólico, uréia e creatinina. Em urina, foram analisados os níveis de FB1, creatinina para correção do volume urinário e a relação Sa/So. Em cabelo, foram analisados os resíduos de FB1 através de CLAE acoplada a espectrometria de massas. Todos os métodos de análise foram submetidos a procedimento de otimização e validação intra--laboratorial. A incidência de FB1 nos alimentos foi, em média, 72% (n=122) nas amostras do Grupo A (Pirassununga/SP) e 35% (n=17) no Grupo B (Erval Velho/SC). Os maiores níveis foram encontrados em amostras de pipoca provenientes do Grupo B, com uma amostra excedendo o limite de tolerância estabelecido no Brasil (2,500 &micro;g kg-1). A ingestão diária provável média (IDPM) de FB1 no Grupo A foi de 63,3 ng kg-1 peso corpóreo (p.c.) dia-1, que corresponde a 3,1% da ingestão provisória máxima tolerável (IPMT) recomendada para fumonisinas (2.000 ng kg-1 p.c. dia-1). A IDPM do Grupo B apresentou uma média de 190,1 ng kg-1 p.c. dia-1 o que corresponde a 9,5% da IDMT. As concentrações de ácido fólico nas amostras de farinha de milho variaram de < 0,3 &micro;g kg-1 (limite de quantificação do método) a 1.705 &micro;g kg-1, com média de 713 &plusmn; 435 &micro;g kg-1. Somente uma amostra apresentou nível de ácido fólico acima do valor mínimo estabelecido pela ANVISA. Em urina, a incidência de FB1 foi de 33,4% (n=251), com níveis médios de 3,19 &plusmn; 3,15 ng mg-1 de creatinina. Não houve correlação (P&gt;0,05) entre as concentrações de FB1 na urina e nos alimentos. Os níveis de esfinganina foram mais elevados em mulheres, com 25,0% (n=116) de amostras positivas, em comparação à urina de homens, 10,4% (n=96). A relação Sa/So apresentou em média 0,91, 0,77 e 0,89 para urina de mulheres, homens e em combinação, respectivamente. Em soro, os níveis de esfingosina foram em média 2,48 ng mL-1 para o Grupo A e 5,01 ng mL-1 para o Grupo B. A relação Sa/So variou de 0,06 a 3,19 com média de 0,79 para o Grupo A e 0,78 para o Grupo B. Embora tenha havido correlação positiva (r=0,574, P&lt;0,05) entre a relação Sa/So no soro e os dados de consumo de milho e derivados obtidos no QIR-24 h, não foram observadas correlações (P&gt;0,05) entre a ingestão de FB1 e a relação Sa/So na urina ou soro. A concentração de ácido fólico no soro variou de 6,7 a 24,0 ng mL-1 (média de 13,4 &plusmn; 5,4 ng mL-1), com ambos os grupos (A e B) apresentando resultados dentro dos valores de referências. Não foram observados níveis detectáveis de FB1 nas amostras de soro. No entanto, FB1 foi detectada em 4 amostras de cabelo humano (7,2%) dos Grupos A e B, cuja concentração média foi de 21,3 &plusmn; 12,1 ng g-1. Em síntese, os resultados obtidos nas análises de biomarcadores de FB1 no presente trabalho estão de acordo com os valores de IDPM encontrados, indicando que a exposição a FB1 nas populações estudadas não representa um risco a saúde. / Fumonisin B1 (FB1) is a mycotoxin produced by the secondary metabolism of Fusarium species, mainly F. verticillioides and F. proliferatum, which contaminates foods before and after processing and causes serious problems to public health and food quality. The aim of this study was to evaluate the human exposure to FB1 in food by means of estimated intake of toxin in the diet, and analysis of different biomarkers in serum, urine and hair. In addition, folic acid in food and blood as well urea and creatinin in serum were investigated to evaluate the toxin effects. The study was conducted in two cities of Sao Paulo and Santa Catarina States, where the respective volunteers were categorized as low-consumers of corn products (Group A, volunteers from Pirassununga/SP) and high-consumers of corn products (Group B, volunteers from Erval Velho/SC). Food samples from Group A (Pirassununga/SP) were provided by volunteers (n=100) in June/2011, September/2011, December/2011 and March/2012. The volunteers from Group B (Erval Velho/SC) (n=20) provided food samples in April/2012. In each group, a list of 20 corn products was given to volunteers, to allow them to check and collect the food items available in their homes at each sampling time. The total number of samples of corn products provided by the volunteers were 122 and 17 in Group A and Group B, respectively. Addicionally, a Food Frequency Questionnaire (FFQ) and a 24-Hours Dietary Recall Questionnaire (24h-DRQ) were applied by the time of sample collections. In each month of food samples collection, samples of blood, urine (only Group A) and hair from the volunteers were collected and storage at -20ºC (urine and hair) or -80ºC (blood) until analysis. Food samples were submitted to determination of FB1, and corn meal samples were also evaluated for folic acid levels. Both analysis were performed by high performance liquid chromatography (HPLC). In serum, analyses included sphinganine/sphingosine ratio (Sa/So), FB1 residue, folic acid, urea and creatinine. In urine, the levels of FB1, creatinine to correct urinary volume and Sa/So ratio were evaluated. In hair, FB1 residues were analysed by HPLC coupled to mass spectrometry. All the analytical methods were submitted to optimization and intra-laboratorial validation procedures. The mean incidences of FB1 in corn products were 72% (n=122) in samples of Group A (Pirassununga/SP), and 35% (n=17) of Group B (Erval Velho/SC). The higher levels were found in popcorn from Group B, with one sample exceeding the tolerance limit established in Brazil (2,500 &micro;g kg-1). The mean probable daily intake (PDIM) of FB1 in Group A was 63.3 ng kg-1 body weigh (b.w.) day-1, which corresponds to 3.1% of provisional maximum tolerable intake (PMTDI) recommended for fumonisins (2,000 ng kg-1 b.w. day-1). PDIM of Group B was 190.1 ng kg-1 b.w. day-1, which represents 9.5% of PMTDI. Folic acid levels in corn meal ranged from &LT; 0,3 &micro;g kg-1 (quantification limit) to 1.705 &micro;g kg-1, with a mean of 713 &plusmn; 435 &micro;g kg-1. Only one sample had levels of folic acid above the minimum established by ANVISA. In urine, the incidence of FB1 was 33,4% (n=251), at mean levels of 3,19 &plusmn; 3,15 ng mg-1 of creatinine. There wasn\'t correlation (P&gt;0.05) between concentrations of FB1 in urine and foods. Sphinganine levels were higher in woman, with 25.0% (n=116) of positive samples in comparison to urine of men, 10.4% (n=96). The mean Sa/So ratios were 0.91, 0.77 and 0.89 for urine of women, men and in combination, respectively. In serum, sphingosine presented a mean of 2.48 ng mL-1 to Group A and 5.01 ng mL-1 to Group B. Sa/So ratio ranged from 0.06 to 3.19 with a mean of 0.79 to Group A and 0.78 to Group B. Although a positive correlation (r=0.574, P&lt;0.05) was found between Sa/So ratio in serum and corn consumption data obtained by 24h-DRQ, no correlation was observed (P&gt;0,05) with FB1 intake and Sa/So ratio in urine or serum. Folic acid concentration in serum ranged from 6.7 to 24.0 ng mL-1 (mean of 13.4 &plusmn; 5.4 ng mL-1), with both groups (A and B) presenting levels within the reference valuies. There were no detectable levels of FB1 in serum samples. However, FB1 was detected in 4 human hair samples (7.2%) of Groups A and B, at a mean concentration was 21.3 &plusmn; 12.1 ng g-1. In summary, the results obtained in the analyses of FB1 biomarkers in the present study are in agreement with the PDIM values found, hence indicating that FB1 exposure in the populations studied do not represent a health concern.
26

Reaction of carbon nanotubes with chemical disinfectants: Byproduct formation and implications for nanotube environmental fate and transport

Verdugo, Edgard Manuel 01 July 2015 (has links)
Nanomaterials (materials which have at least one dimensional feature with length less than 100 nanometers), and carbon nanotubes (CNTs) specifically, have exhibited great potential in water treatment. CNTs are cylindrical structures comprising single or multiple concentric graphene sheets and have diameters from less than 1 nanometer (nm) up to 50 nm (one nm is one millionth of a millimeter). Due to their unique and tunable structural, physical, and chemical properties, CNTs are used in environmental remediation as absorbents, catalysts or catalyst supports, membranes, and electrodes. However, a poorly understood determinant of the role of CNTs in water treatment is their interaction with chemical disinfectants (e.g., chlorine, chloramine, and ozone). To address these existing gaps in the environmental fate and reactivity of CNTs, this work establishes whether CNTs represent precursors for halogen and nitrogen containing disinfection byproducts (DBPs), which are products that form during a reaction of a disinfectant with organic matter in the water. In addition, we seek to understand how reaction with disinfectants alters CNT surface chemistry, and in turn impacts their environmental mobility and cytotoxicity. Finally, we determine how NOM and other aquatic variables known to impact DBP formation (e.g., Br−, NOM, and pH) influence the rate and products of CNT reaction with disinfectants. Outcomes of this work contribute to the current understanding of the role of carbon-based species as DBP precursors in disinfection and provide new context as to the environmental significance and implications of CNTs in natural and engineered aquatic systems.
27

Recycled Materials Relational Database: Design and Implementation Aspects

McDonald, Rory Morgan 25 June 2004 (has links)
Although there has been a rise in the use of recycled materials in highway and geotechnical systems, many tons of potentially useful industrial and domestic by-products are still being discarded in the United States each year. While extensive research has been conducted to investigate the use of recycled materials in engineering applications, the dissemination of the findings is often limited. The problem is compounded by the lack of a single resource containing relevant engineering and environmental characteristics of each material; the tendency of the researchers to publish their findings in technical reports rather than archived publications; and the wide discrepancies among local and state environmental regulations and acceptability. A relational database is proposed as a method to improve implementation of recycled material research. A comprehensive review is conducted on data available for a wide variety of recycled materials and their usage in highway and geotechnical applications. Mechanical and environmental data and information from case histories are organized into approximately 10 tables in a relational database management system. More than 30 parameters, including engineering properties, availability and cost, are recorded for 23 materials in a highly-organized compendium. Through a simple user interface, a vast amount of data can be sorted to implement a recycled material program based on historic and current data. The DBMS is updatable and the design is amendable to account for future expansion.
28

Removal of Assimilable Organic Carbon and Disinfection By-Products Formation Potential from Water Treatment Plant Using a Biological Activated Carbon Process

Hung, Pi-hsia 04 July 2010 (has links)
Taiwan Water Supply Cooperation (TWSC) has upgraded traditional purification processes into advanced treatment systems in south Taiwan for many years. The removal efficiency of assimilable organic carbon (AOC) by ultrafiltration (UF) with reverse osmosis (RO) systems was 47% was lower than that of 62% by ozone with biological activated carbon system (BAC). In this work, we investigate the removal of AOC and disinfection by products formation potential (DBPFP) of raw water took from a water treatment plant by using BAC and membrane treatment units. BAC system of granular activated carbon(GAC) and powder activated carbon (PAC) showed two kind carbons have certain efficiency for AOC removal. Results we found could reach above 50% (from 44.28¡Ó9.84£gg acetate-C/L reduce to 20.93¡Ó4.25£gg acetate-C/L for GAC and from 45.92¡Ó17.75£gg acetate-C/L reduce to 21.23¡Ó4.25£gg acetate-C/L for PAC), when hydraulic retention time (HRT) in BAC reactor was at 1 hour. When HRT raised to 6 hours the concentration of AOC in effluent of BAC systems were reduced under 15 £gg/L, and removal efficiency could reach above 70%. The suggested limit level of AOC is 50 £gg/L of drinking water. In removal of DBPFP, BAC of two carbons has showed certain efficiency on trihalomethanes formation potential (THMFP) and haloacetic acids formation potential (HAA5FP). The results were done in removal of THMFP (from 20.54¡Ó6.48£gg/L reduce to 14.21¡Ó4.47£gg/L for GAC and from 24.64¡Ó6.74£gg/L reduce to 14.75¡Ó4.04£gg/L for PAC) and HAA5FP (from 39.64¡Ó10.38£gg/L reduce to 17.35£gg/L for GAC and from 17.86¡Ó5.13£gg/L reduce to 11.76¡Ó3.76£gg/L for PAC) in BAC reactors. They were all lower than national standard of drinking water (THMs 80£gg/L, HAAs 60£gg/L). It is believed that two kind carbons in BAC system could all reduce effectively on AOC and DBPFP to obtain high quality of drinking water with biological stability at HRT of 6 hours.
29

Study on the Treatment Efficiency of ATP and Application of Powdered Acti vated Carbon and Membrane Bioreactor to Remove Organic Compounds in Drinking Water

Huang, Chine-er 24 July 2009 (has links)
To improve water quality of drinking water, the Taiwan Water Supply Corp (TWSC) upgraded three water treatment plants (WTP), changing traditional treatment processes into two advanced membrane processes and one advanced ozonation processes in recent years. Membrane water treatment units of the water treatment plant comprise ultrafiltration (UF) and reverse osmosis (RO). And the advanced ozonation water treatment units comprise pellet softening, post-ozonation and biological activated carbon (BAC) adsorption. This study investigated the formation of disinfection byproducts (DBPs), dissolved organic carbon (DOC) and assimilable organic carbon (AOC) at two advanced water treatment plants (ATP) in Kaohsiung City, Taiwan, by implementing a sampling program. The purposes of this study include¡G(1) The evaluation of treatment efficiency of advanced water treatment plants. (2) Application of powdered activated carbon and membrane bioreactor in removing organic compounds in drinking water. TCM was by far the predominant species in the finished water, the average concentration of DPBs in this study at both plants were 13.97¡Ó4.18£gg/L and 21.49¡Ó10.59£gg/L of THMs for plant A and plant B, respectively. However, levels for DPBs compound are low in both plants and lower than the current national drinking water quality standards 80 £gg / L. But for anther typical DPBs (HAAs compounds), the average concentrations were 17.67¡Ó14.50£gg/L and 33.03¡Ó16.24£gg/L of HAA5 for plant A and plant B, respectively. DCAA and TCAA were the two major species of HAAs found in the two water samples under study. The sums of the two species represented in finished water were about 67% and 83% of HAA5 in A and plant B, respectively. The results showed that HAA5 concentration of all samples could meet current USEPA standards for drinking water quality. Importantly, our work show the advanced treatment processes have good removal on DPBs of treated water. In organic compounds removal, there is high efficiency by using post-ozonation combined with BAC, but low efficiency for membrane process due to the inhibition of electrical charge happened on surface of membrane. This inhibition is caused probably by high hardness and high ion strength in water. We found by combining BAC with membrane filtration process will effectively remove the organic compounds and lower the concentration of AOC for passing the limit value suggested in related researches of the world.
30

Evaluation of agro-Industrial by-products as protein sources for duck production in the Mekong Delta of Vietnam /

Nguyen, Thi Kim Dong, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

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