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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.
1

Sustainable utilisation of raw sewage sludge (RSS) as a water replacement in cement-based materials containing unprocessed fly ash

Hamood, Alaa January 2014 (has links)
Prior to the implementation of the European Union Urban Waste Water Treatment Directive (91/271/EEC) in 31 Dec 1998, around a quarter of the sewage sludge produced in the UK was either discharged to surface waters via pipes or disposed from ships at sea. Discontinuing this route together with the quality requirements of the European Waste Water Directive, led to the generation of significant quantities of sewage sludge. It has therefore become required to treat this waste effectively before it can be sent back to the environment. Consequently, this added greater challenges for the environmental agencies, as well as local authorities. The treatment process comprises costly and energy consuming applications including physical, chemical, biological and thermal. In addition to the sewage sludge, the power generation industry produces massive quantities of fly ash from burning coal. In the UK, there is about 5,300,000 tonnes of fly ash that are generated annually, which require to be processed and classified in order to meet the standard requirements before it can be used in the construction applications. The classifying process also involves a series of costly and energy consuming mechanical and physical applications. This research programme has introduced an innovative alternative to the traditional re-use and disposal routes of Raw Sewage Sludge (RSS) and unprocessed fly ash. It has suggested the utilisation of RSS and unprocessed fly ash as raw ingredients for the production of sustainable construction materials. This research programme has therefore examined the performance of cement-based materials containing Raw Sewage Sludge (RSS) as a water replacement and unprocessed fly ash as cement replacement. Mortar and concrete mixes incorporating these materials were tested for their flowability/workability, density, Total Water Absorption (TWA), Ultrasonic Pulse Velocity (UPV), compressive strength, flexural strength, drying shrinkage, sulphate attack and leaching properties. Three series of cement-based materials were studied including mortar mixes with RSS and unprocessed fly ash (Series 1), mortar mixes with RSS and large proportions of unprocessed fly ash (Series 2), and concrete mixes with RSS and unprocessed fly ash (Series 3). The outcomes of the investigation were encouraging in that cement-based materials containing RSS and unprocessed fly ash that were produced demonstrated relatively good engineering, durability and environmental properties in comparison to the control mixes. The inclusion of unprocessed fly ash significantly reduced flowability/workability; however it improved long-term compressive strength for both mixes with RSS and water. The best compressive strength results were recorded when cement was replaced with 10-20% unprocessed fly ash by weight of total binder. The results also showed that sulphate attack resistance improved when fly ash was included. Moreover, safe concentration levels of heavy metals and free ions were detected when leaching test was performed. However, it must be kept in mind that more environmental tests must be performed before any large scale use is undertaken.
2

Quantificação e caracterização genotípica de Cryptosporidium spp.isolados de água bruta superficial e esgoto bruto para a monitorização em mananciais de abastecimento público na Região Metropolitana de São Paulo (RMSP) / Quantification and molecular characterization of Cryptosporidium spp. from raw surface water and raw sewage for the monitoring of public water supply sources in the metropolitan region of São Paulo

Araujo, Ronalda Silva de 08 April 2015 (has links)
As doenças de veiculação hídrica, sobretudo aquelas causadas por protozoários intestinais, emergiram como um dos principais problemas de saúde pública. Diferentes aspectos são abordados sobre a biologia e a epidemiologia dos principais protozoários parasitas de transmissão hídrica. Cryptosporidium está descrito como um importante parasita associado a casos de surtos de veiculação hídrica e alimentos no mundo. A epidemiologia complexa desse protozóario e o fato de que a maioria das espécies e genótipos não pode ser diferenciada morfologicamente, aumentam o interesse por metodologias sensíveis e rápidas na detecção de espécies responsáveis pela infecção em humanos. Neste estudo foram avaliadas 50 amostras de água bruta superficial, coletadas no Rio São Lourenço da Serra (P1A) e Represa de Guarapiranga (P2A) e 50 de esgoto bruto coletadas em São Lourenço da Serra (P1E) e no poço vertical de Taboão da Serra (P2E) entre os meses de janeiro e dezembro de 2013. O isolamento dos oocistos na água foi realizado pelo Método 1623.1 e as amostras de esgoto bruto por centrifugação, separação imunomagnética (IMS). A caracterização genotípica ocorreu por meio da nested PCR, clonagem e sequenciamento com base no gene 18S rRNA comum a todas as espécies de Cryptosporidium. O ensaio de PCR em tempo real (qPCR) foi avaliado simultaneamente para detecção e quantificação de oocistos nas amostras. De acordo com os resultados obtidos pela nested PCR, Cryptosporidium foi detectado na água bruta superficial em 12 por cento (3/25) no manancial P1A e 16 por cento (4/25) no P2A. No esgoto bruto o parasito foi detectado em 20 por cento (5/25) das amostras no ponto P1E e 24 por cento (6/25) no poço vertical P2E. A qPCR detectou 52 por cento (0,79 a 1,85 oocistos/L) de amostras positivas no manancial P1A e o parasito foi detectado em 64 por cento (0,72 a 1,4 oocistos/L) no manancial P2A. No esgoto bruto 72 por cento das amostras foram positivas tanto no ponto P1E (7 a 655 oocistos/L) como no P2E (5 a 519 oocistos/L). A caracterização molecular permitiu a identificação de C. parvum e C. hominis na água bruta superficial, e C. hominis, C. parvum, e C. muris no esgoto bruto. As espécies do gênero Cryptosporidium identificadas neste estudo apresentam expressiva relevância para o desenvolvimento da doença humana. Neste sentido, as metodologias de concentração e caracterização empregadas nas análises demonstraram no geral, o potencial para aplicação em estudos de vigilância ambiental e foram úteis na diferenciação de espécies patogênicas. A presença de C. muris associada às espécies antroponóticas identificadas auxiliou na investigação de prováveis fontes de contaminação no ambiente confirmando a necessidade da expansão de medidas efetivas para proteção destes mananciais. / Waterborne diseases, especially those caused by intestinal protozoa, have emerged as a major public health problem. Different aspects are addressed on the biology and epidemiology of most waterborne protozoan parasites. Cryptosporidium is described as an important parasite associated with cases of waterborne and food outbreaks in the world. The complex epidemiology of this protozoan, as well as the fact that most species and genotypes cannot be differentiated morphologically, increase the interest for sensitive and rapid methods for the detection of species responsible for infection in humans. In this study, 50 samples of raw surface water were collected from São Lourenço River (P1A) and Guarapiranga Dam (P2A), and 50 samples of raw sewage were collected from São Lourenço da Serra (P1E) and from Taboão da Serras vertical well (P2E), between January and December of 2013. The isolation of oocysts in water was carried out by the USEPA Method 1623.1 and raw sewage samples were processed by centrifugation, immunomagnetic separation (IMS). Genotypic characterization occurred by nested PCR, cloning and sequencing based on 18S rRNA gene, which is common to all Cryptosporidium species. Real time PCR assays (qPCR) were carried out both for detection and quantification of oocysts simultaneously in the samples. According to the results obtained by nested PCR, Cryptosporidium was detected in raw surface water in 12 per cent (3/25) of samples at P1A and in 16 per cent (4/25) at P2A. In raw sewage the parasite was detected in 20 per cent (5/25) of samples at P1E and 24 per cent (6/25) in P2E vertical well. qPCR detected 52 per cent (0.79 to 1.85 oocysts/L) of positive samples at P1A, while the parasite was detected in 64 per cent (0.72 to 1.4 oocysts/L) of samples at P2A water supply. Regarding raw sewage, 72 per cent of samples were positive both at P1E (7 to 655 oocysts/L) and P2E (5 to 519 oocysts/L Molecular characterization allowed the identification of C. parvum and C. hominis in raw surface water, and C. hominis, C. parvum and C. muris in raw sewage. Cryptosporidium species identified herein belong to a group of organisms of significant relevance in waterborne diseases. Therefore, concentration and characterization methodologies applied in our analyses showed to be useful for environmental surveillance studies, as well as they were useful in the differentiation of human pathogens. The presence of C. muris associated to anthroponotic species helped in the investigation of likely contamination sources in the environment, confirming the need of expansion in effective measures to protect these water supplies.
3

Quantificação e caracterização genotípica de Cryptosporidium spp.isolados de água bruta superficial e esgoto bruto para a monitorização em mananciais de abastecimento público na Região Metropolitana de São Paulo (RMSP) / Quantification and molecular characterization of Cryptosporidium spp. from raw surface water and raw sewage for the monitoring of public water supply sources in the metropolitan region of São Paulo

Ronalda Silva de Araujo 08 April 2015 (has links)
As doenças de veiculação hídrica, sobretudo aquelas causadas por protozoários intestinais, emergiram como um dos principais problemas de saúde pública. Diferentes aspectos são abordados sobre a biologia e a epidemiologia dos principais protozoários parasitas de transmissão hídrica. Cryptosporidium está descrito como um importante parasita associado a casos de surtos de veiculação hídrica e alimentos no mundo. A epidemiologia complexa desse protozóario e o fato de que a maioria das espécies e genótipos não pode ser diferenciada morfologicamente, aumentam o interesse por metodologias sensíveis e rápidas na detecção de espécies responsáveis pela infecção em humanos. Neste estudo foram avaliadas 50 amostras de água bruta superficial, coletadas no Rio São Lourenço da Serra (P1A) e Represa de Guarapiranga (P2A) e 50 de esgoto bruto coletadas em São Lourenço da Serra (P1E) e no poço vertical de Taboão da Serra (P2E) entre os meses de janeiro e dezembro de 2013. O isolamento dos oocistos na água foi realizado pelo Método 1623.1 e as amostras de esgoto bruto por centrifugação, separação imunomagnética (IMS). A caracterização genotípica ocorreu por meio da nested PCR, clonagem e sequenciamento com base no gene 18S rRNA comum a todas as espécies de Cryptosporidium. O ensaio de PCR em tempo real (qPCR) foi avaliado simultaneamente para detecção e quantificação de oocistos nas amostras. De acordo com os resultados obtidos pela nested PCR, Cryptosporidium foi detectado na água bruta superficial em 12 por cento (3/25) no manancial P1A e 16 por cento (4/25) no P2A. No esgoto bruto o parasito foi detectado em 20 por cento (5/25) das amostras no ponto P1E e 24 por cento (6/25) no poço vertical P2E. A qPCR detectou 52 por cento (0,79 a 1,85 oocistos/L) de amostras positivas no manancial P1A e o parasito foi detectado em 64 por cento (0,72 a 1,4 oocistos/L) no manancial P2A. No esgoto bruto 72 por cento das amostras foram positivas tanto no ponto P1E (7 a 655 oocistos/L) como no P2E (5 a 519 oocistos/L). A caracterização molecular permitiu a identificação de C. parvum e C. hominis na água bruta superficial, e C. hominis, C. parvum, e C. muris no esgoto bruto. As espécies do gênero Cryptosporidium identificadas neste estudo apresentam expressiva relevância para o desenvolvimento da doença humana. Neste sentido, as metodologias de concentração e caracterização empregadas nas análises demonstraram no geral, o potencial para aplicação em estudos de vigilância ambiental e foram úteis na diferenciação de espécies patogênicas. A presença de C. muris associada às espécies antroponóticas identificadas auxiliou na investigação de prováveis fontes de contaminação no ambiente confirmando a necessidade da expansão de medidas efetivas para proteção destes mananciais. / Waterborne diseases, especially those caused by intestinal protozoa, have emerged as a major public health problem. Different aspects are addressed on the biology and epidemiology of most waterborne protozoan parasites. Cryptosporidium is described as an important parasite associated with cases of waterborne and food outbreaks in the world. The complex epidemiology of this protozoan, as well as the fact that most species and genotypes cannot be differentiated morphologically, increase the interest for sensitive and rapid methods for the detection of species responsible for infection in humans. In this study, 50 samples of raw surface water were collected from São Lourenço River (P1A) and Guarapiranga Dam (P2A), and 50 samples of raw sewage were collected from São Lourenço da Serra (P1E) and from Taboão da Serras vertical well (P2E), between January and December of 2013. The isolation of oocysts in water was carried out by the USEPA Method 1623.1 and raw sewage samples were processed by centrifugation, immunomagnetic separation (IMS). Genotypic characterization occurred by nested PCR, cloning and sequencing based on 18S rRNA gene, which is common to all Cryptosporidium species. Real time PCR assays (qPCR) were carried out both for detection and quantification of oocysts simultaneously in the samples. According to the results obtained by nested PCR, Cryptosporidium was detected in raw surface water in 12 per cent (3/25) of samples at P1A and in 16 per cent (4/25) at P2A. In raw sewage the parasite was detected in 20 per cent (5/25) of samples at P1E and 24 per cent (6/25) in P2E vertical well. qPCR detected 52 per cent (0.79 to 1.85 oocysts/L) of positive samples at P1A, while the parasite was detected in 64 per cent (0.72 to 1.4 oocysts/L) of samples at P2A water supply. Regarding raw sewage, 72 per cent of samples were positive both at P1E (7 to 655 oocysts/L) and P2E (5 to 519 oocysts/L Molecular characterization allowed the identification of C. parvum and C. hominis in raw surface water, and C. hominis, C. parvum and C. muris in raw sewage. Cryptosporidium species identified herein belong to a group of organisms of significant relevance in waterborne diseases. Therefore, concentration and characterization methodologies applied in our analyses showed to be useful for environmental surveillance studies, as well as they were useful in the differentiation of human pathogens. The presence of C. muris associated to anthroponotic species helped in the investigation of likely contamination sources in the environment, confirming the need of expansion in effective measures to protect these water supplies.

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