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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.
31

Pinguim-de-Magalhães (Spheniscus magellanicus) como indicador da ocorrência de poluentes orgânicos persistentes / Magellanic Penguin (Spheniscus magellanicus) as a persistent organic pollutants indicator

Paula Baldassin Jorge 04 June 2014 (has links)
O Pinguim-de-Magalhães, Spheniscus magellanicus, é o mais abundante dos pinguins que vivem em regiões temperadas da América do Sul, sendo um bom indicador de poluição ambiental. Poluentes orgânicos persistentes (POPs) foram detectados em fígado de Pinguins-de-Magalhães encontrados debilitados ou mortos nas praias do Brasil (Rio de Janeiro, São Paulo, Santa Catarina e Rio Grande do Sul) entre 2008 - 2012 e, do Uruguai e do Chile, em 2011. Os bifenilos policlorados (PCBs) predominaram em relação aos pesticidas organoclorados (DDTs ∼ HCB ∼ Drins) e aos éteres difenilos polibromados (PBDEs). O contaminante emergente fipronil não foi detectado apesar de seu uso na América do Sul. Entre os PCBs predominaram os congeneres penta, hexa e heptaclorados. Concentrações de POPs foram similares entre as áreas de migração e reprodução exceto para os PCBs que foram relativamente maiores na área de reprodução. Avaliação temporal (2008 - 2012) de POPs apresentou constância para os pesticidas organoclorados e tendência ao declínio para os PCBs. A glândula uropigiana de Pinguim-de-Magalhães mostrou-se um tecido alternativo adequado para análise de POPs em aves debilitadas. No geral, as regiões de reprodução e migração dos pinguins na América do Sul apresentam baixas concentrações de POPs com tendência constante ou indícios de declínio. / The Magellanic Penguin , Spheniscus magellanicus, is the most abundant penguin that live in temperate regions of South America and a good indicator of environmental pollution in that region. Persistent organic pollutants (POPs) were detected in the liver of Magellanic penguins found debilitated or dead on the beaches of Brazil (Rio de Janeiro, Sao Paulo, Santa Catarina and Rio Grande do Sul) between 2008 - 2012, and in Uruguay and Chile in 2011. Polychlorinated biphenyls (PCBs) were more prevalent than organochlorine pesticides (DDTs ∼ HCB ∼ Drins) and polybrominated diphenyl ethers (PBDEs). Fipronil, an emerging contaminant, was not detected despite its use in South America. Among PCBs, the congeners penta, hexa and heptaclorados were predominant. Concentrations of POPs are similar between the migration and reproduction areas except for PCBs that are relatively higher in the breeding area. At this time point (2008 - 2012) POPs showed constancy for organochlorine pesticides and PCBs tendency to decline. The Magellanic penguin uropygian gland has proved to be a suitable alternative for POPs tissue analysis in debilitated birds. Overall, southern South America has low concentrations of POPs with constant trend or decline evidence.
32

Avaliação da qualidade da água da Bacia do Alto Jacaré-Guaçu/SP (Ribeirão do Feijão e Rio do Monjolinho) através de variáveis físicas, químicas e biológicas / Evaluation of the water quality of Alto Jacaré-Guaçu Basin (Ribeirão do Feijão and Rio do Monjolinho), São Paulo State, by the physical, chemical and biological conditions

Marlon Peláez Rodríguez 29 November 2001 (has links)
Os recursos hídricos urbanos são de grande importância para os municípios que têm desenvolvimento econômico crescente e aumento demográfico, sendo que a manutenção da qualidade da água dos mananciais de abastecimento para a população é imprescindível para a saúde e para diminuir o custo econômico. A bacia do Alto Jacaré-Guaçu, em cuja área está inserido o município de São Carlos/SP, tem como principais sub bacias a do Rio do Monjolinho e a do Ribeirão do Feijão, sendo este a principal fonte de abastecimento de água para a cidade. O trabalho foi proposto para avaliar a qualidade da água dos recursos hídricos da bacia do Alto Jacaré-Guaçu, através da análise das características limnológicas, das substâncias tóxicas e da comunidade de macroinvertebrados que permitem a indicação da qualidade da água. Foram efetuadas duas campanhas de amostragem em 1999: a) no período chuvoso (em março) e b) no período de estiagem (em agosto). Em março foram realizadas amostragens em 8 pontos e, em agosto, foram acrescidos mais 6 pontos, totalizando 14. Paralelamente, com o intuito de visualizar espacialmente os resultados e desta forma identificar as áreas com maior ou menor grau de impacto, foi elaborado um mapa com as sub-bacias correspondentes às áreas cuja água drena para cada um dos pontos de coleta. Os resultados obtidos demonstram que a qualidade da água no período da estiagem se torna mais critica devido à diminuição do fluxo da água. Com relação à poluição orgânica, a sub bacia do Monjolinho pode ser classificada em 3 grupos: a) trecho sem influência urbana, portanto não poluída ou ligeiramente poluída; b) trecho com influência da área urbana da cidade de São Carlos, sendo assim, fortemente poluída e c) trecho final do Rio Monjolinho, com uma poluição moderada ou em processo de recuperação. Quanto à presença de substâncias tóxicas analisadas as concentrações dos metais, em geral, apresentaram-se dentro dos limites da Resolução CONAMA 20/86, exceto o cobre, ferro, manganês e zinco. Já para os organoclorados, a maior parte da área da bacia não atende a Resolução Brasileira, detectando-se concentrações acima dos limites permitidos. Quanto à identificação dos diferentes impactos no uso da terra e da água na bacia do Alto Jacaré-Guaçu, pode-se citar, entre as atividades antrópicas que vem acelerando o processo de degradação ambiental, principalmente a qualidade da água :1- Falta de tratamento do esgoto doméstico, principalmente na área urbana; 2- Desmatamento contínuo levando a substituição da vegetação natural por monoculturas e pastagens; 3- Uso irregular do solo, causando erosão e assoreamento nos corpos de água; 4- Expansão sem controle da área urbana próximo às margens e principalmente nas nascentes dos corpos de água e 5-Falta de controle na comercialização e uso de defensivos agrícolas. / The water resources in urban areas are important for the municipalities in stage of economical development and demographic increase. The maintenance of quality of the water sources is indispensable for the human health and to reduce the economic costs. The Alto Jacaré-Guaçu basin, situated in São Carlos municipality, has as a principal sub-basins the Monjolinho River and Ribeirão do Feijão basins. Both are the main souce of water supply for the city. This study was proposed to analyze the water quality of the Alto Jacaré-Guaçu basin, according to the limnological conditions, toxic substances and utilization of macroinvertebrates as indicative of the water quality. Sampling was carried out in two periods: a) in the rainy season (March 1999) and b) in the dry season (August 1999). In March 8 stations were sampled, while in August 6 more stations were sampled, totalizing 14 stations. In Parallel, a map was elaborated with the sub-basins corresponding to the drainage area for each station in order to show spatially the results and to identify the areas with bigger or minor degree of impact. The results demonstrated that the water quality in the dry period became critical due to decreasing of the water flow. Concerning to the organic pollution, the sub-basin of Monjolinho can be classified under 3 groups: a) section without urban influence, with no or few pollution; b) section with no or few pollution; b) section with influence of the urban area of São Carlos city, being strongly contaminated and c) final section the Monjolinho River, with a moderate pollution or in process of recovery. In relation to the presence of toxic substances analyzed, the concentrations of metals generally appeared inside the limits of the Resolution CONAMA 20/86, except for copper, iron, manganese and zinc. For the organochlorine pesticides, the concentrations oberseved do not attend to the Brazilian Resolution, because the values were higler than the acceptable limits. Concerning to the identification of different impacts of the land and water uses in the Alto Jacaré-Guaçu basin, it is possible to identify the human activities that accelerate the process of environmental degration, specially for the water quality: 1- The lack of teatment of the domestic residues, specially in the urban area; 2- Continous deforestation and changing of natural vegetation to monocultures and pastures; 3-Irregular uses of the soil causing erosion and collapsing the water bodies; 4- Expansion without control of the urban area next to the margins and specially in the headwaters, and 5- Lack of control in the selling and uses of agricultural pesticides.
33

Distribuce organochlorových pesticidů do životního prostředí / Distribution of organochlorine pesticides into the environment

Plačková, Lucie January 2011 (has links)
The master’s thesis was focused on the determination of persistent organic pollutants, namely polychlorinated biphenyls were detected (PCB 28, 52, 101, 118, 138, 153 and 180) and organochlorine pesticides. A total of 31 were evaluated contamination of organochlorine compounds. The level of contamination by organic pollutants were detected in 20 samples, 9 samples were sediments from the river Jevišovka, which is located in the South Moravia and 11 samples represented arable soil samples and were collected in the vicinity of this river. In the theoretical part are characterized both groups of substances, their fate in the environment and negative effects on living organisms. The experimental part focuses on the sampling procedures and processing for analysis by gas chromatography. There is described a complex analytical process involving the three extraction methods (accelerated solvent extraction, microwave extraction and ultrasonic extraction), extract purification and self-determination by gas chromatography with electron capture detector (GC / ECD). In the samples of sediment were detected these PCB congeners (138, 153 and 180) and organochlorine pesticides (b-HCH, HCB, p,p’-DDE, p,p’-DDD, p,p’-DDT and o,p’-DDT).. In soil samples were detected PCB congener 28 and organochlorine pesticides (HCB, b-HCH, heptachlor, aldrin, dieldrin, p,p’-DDE, p,p’-DDD, p,p’-DDT and o,p’-DDT).
34

Persistentní organické polutanty v životním prostředí Jihomoravského kraje / Persistent Organic Pollutants in the Environment of the Southern Moravia Region

Lána, Radim January 2008 (has links)
Byla provedena studie bioakumulace POP v potravním řetězci a historických trendů hladin POP v sedimentech Brněnské přehrady. Současné úrovně kontaminantů byly stanoveny v jelci tloušti z řeky Svratky a rovněž byla posouzena hygienická kvalita ryb z rekreačního rybolovu. Současné úrovně POP v terestrickém ekosystému byly posouzeny pomocí analýz jehličí jako přirozeného indikátoru znečištění. Studium jedinců tří druhů dravých ptáků z ČR bylo zaměřeno na zhodnocení kontaminace těchto vrcholných predátorů POP. S pomocí analýz vybraných druhů ryb ze Záhlinických rybníků byl rovněž studován proces bioakumulace. Posouzení parametrů dvou moderních extrakčních technik a jejich využitelnosti pro izolaci POP z různých matric bylo námětem poslední části dizertace.
35

Organochlorine Pesticides and Heavy Metals in Fish From the Trinity River, Texas

Martinez, Maria L., 1960- 05 1900 (has links)
The Trinity River passes through the Dallas-Fort Worth metroplex receiving point and non-point source contaminant loadings. Lepomis spp. were collected at twelve sampling locations in the Trinity River in August 1987 and September 1988 and analyzed for organochlorine pesticides and heavy metals. Results from the study were compared to existing U.S. FDA action and tolerance levels, LC50s, and historical data. Various longitudinal trends and some concentration patterns were observed. Continual study of pesticide and metal body burdens in fish allow testing for trends, and thereby, lead to a better understanding of the distribution of contaminants in the Trinity River.
36

An investigation of the association between toxin producing staphylococcus, biochemical changes and jaw muscle pain.

McGregor, Neil Roland January 2000 (has links)
Objectives: To assess the expression of the symptoms of jaw muscle pain and its association with alterations in biochemistry, other symptoms and the carriage of staphylococci. Methods: Three different study populations were assessed. The first was selected and examined by the author and consisted of 43 pain and 41 age and sex matched controls. The second was a study of CFS patients who were blinded to the author and the author subsequently examined the associations between jaw muscle symptom reporting and the standardised biochemistry measures. The third study was also blinded to the author but included an investigation of staphylococci and certain cytokine and biochemistry measures. Results: The three studies clearly establish an association between the carriage of toxicogenic coagulase negative staphylococci and the expression of jaw muscle pain in both males and females. These associations were homogeneous and were found whether the patients were selected on the basis of having jaw muscle pain or selected from within a population of patients selected on the basis of having Chronic Fatigue Syndrome. The studies associated the changes with variations in biochemistry and these were in turn associated with symptom expression within the jaw muscle pain patients. These biochemical alterations included the dysregulation of immune cell counts, cytokines, electrolyte and protein metabolism. These symptoms and biochemical changes were associated with pain severity and illness duration and staphylococcal toxin production. From the data a model was developed which shows the mechanisms involved in the development of chronic pain in the jaw muscles. Conclusions: The carriage of toxicogenic coagulase-negative staphylococci were found to be associated with the expression of jaw muscle pain and the alterations in biochemistry associated with these symptoms.
37

An investigation of the association between toxin producing staphylococcus, biochemical changes and jaw muscle pain.

McGregor, Neil Roland January 2000 (has links)
Objectives: To assess the expression of the symptoms of jaw muscle pain and its association with alterations in biochemistry, other symptoms and the carriage of staphylococci. Methods: Three different study populations were assessed. The first was selected and examined by the author and consisted of 43 pain and 41 age and sex matched controls. The second was a study of CFS patients who were blinded to the author and the author subsequently examined the associations between jaw muscle symptom reporting and the standardised biochemistry measures. The third study was also blinded to the author but included an investigation of staphylococci and certain cytokine and biochemistry measures. Results: The three studies clearly establish an association between the carriage of toxicogenic coagulase negative staphylococci and the expression of jaw muscle pain in both males and females. These associations were homogeneous and were found whether the patients were selected on the basis of having jaw muscle pain or selected from within a population of patients selected on the basis of having Chronic Fatigue Syndrome. The studies associated the changes with variations in biochemistry and these were in turn associated with symptom expression within the jaw muscle pain patients. These biochemical alterations included the dysregulation of immune cell counts, cytokines, electrolyte and protein metabolism. These symptoms and biochemical changes were associated with pain severity and illness duration and staphylococcal toxin production. From the data a model was developed which shows the mechanisms involved in the development of chronic pain in the jaw muscles. Conclusions: The carriage of toxicogenic coagulase-negative staphylococci were found to be associated with the expression of jaw muscle pain and the alterations in biochemistry associated with these symptoms.

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