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Anestesianvändning vid depuration utförd av tandhygienisterEdström, Emma, Oliveira Santos, Késia January 2015 (has links)
Syftet med studien var att kartlägga anestesianvändning vid depuration utförd av tandhygienister. Ett ytterligare syfte var att undersöka tandhygienisters anledningar till varför anestesi används eller inte används. En enkätstudie skickades till 148 tandhygienister slumpmässigt utvalda av Sveriges Tandhygienistförening. Nittio enkäter (60,8 %) inkluderades i studiens resultat. Anestesi vid depuration användes främst en till två gånger per vecka med ett medelvärde på 38,6 % (±29,8). Ökat fickdjup resulterade i ökad anestesianvändning vid subgingival rengöring (fickdjup 5-6 mm 43,1 VAS, fickdjup 10< mm 82,4 VAS, Visual Analogue Scale). Anestesiförekomsten var lägre vid avlägsning av supragingival tandsten, fyllningsöverskott samt polering med putspasta. Ytanestesi utan efterföljande injektion var den vanligast förekommande anestesitypen, och den minst använda var mandibularinjektioner. De mest förekommande svaren till varför anestesi används var att ge en smärtfri behandling och att anestesi möjliggör ett bättre utfört arbete. Den vanligaste anledningen till varför anestesi inte används var att patienten avböjer. Det kan ifrågasättas om smärtfri behandling sker tillräckligt ofta, då resultatet tyder på att anestesi används för lite i förhållande till hur mycket depuration som utförs.
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Assessment of the Occurrence and Potential Risks of Pharmaceuticals and their Metabolites in Fish and Water Using Liquid Chromatography Mass SpectrometryWang, Jian 26 March 2013 (has links)
A comprehensive method for the analysis of 11 target pharmaceuticals representing multiple therapeutic classes was developed for biological tissues (fish) and water. Water samples were extracted using solid phase extraction (SPE), while fish tissue homogenates were extracted using accelerated solvent extraction (ASE) followed by mixed-mode cation exchange SPE cleanup and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Among the 11 target pharmaceuticals analyzed, trimethoprim, caffeine, sulfamethoxazole, diphenhydramine, diltiazem, carbamazepine, erythromycin and fluoxetine were consistently detected in reclaimed water. On the other hand, caffeine, diphenhydramine and carbamazepine were consistently detected in fish and surface water samples.
In order to understand the uptake and depuration of pharmaceuticals as well as bioconcentration factors (BCFs) under the worst-case conditions, mosquito fish were exposed to reclaimed water under static-renewal for 7 days, followed by a 14-day depuration phase in clean water. Characterization of the exposure media revealed the presence of 26 pharmaceuticals while 5 pharmaceuticals including caffeine, diphenhydramine, diltiazem, carbamazepine, and ibuprofen were present in the organisms as early as 5 h from the start of the exposure.
Liquid chromatography ultra-high resolution Orbitrap mass spectrometry was explored as a tool to identify and quantify phase II pharmaceutical metabolites in reclaimed water. The resulting data confirmed the presence of acetyl-sulfamethoxazole and sulfamethoxazole glucuronide in reclaimed water. To my knowledge, this is the first known report of sulfamethoxazole glucuronide surviving intact through wastewater treatment plants and occurring in environmental water samples.
Finally, five bioaccumulative pharmaceuticals including caffeine, carbamazepine, diltiazem, diphenhydramine and ibuprofen detected in reclaimed water were investigated regarding the acute and chronic risks to aquatic organisms. The results indicated a low potential risk of carbamazepine even under the worst case exposure scenario. Given the dilution factors that affect environmental releases, the risk of exposure to carbamazepine will be even more reduced.
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Depuration as a method to reduce Vibrio vulnificus populations in live Crassostrea virginica oystersTokarskyy, Oleksandr S 07 August 2010 (has links)
Vibrio vulnificus is a foodborne bacterial pathogen associated with raw oyster consumption. Shellfish depuration for 48 hours is a dynamic process where coliform bacteria are purged; however, this process is ineffective against V. vulnificus. The current study investigated the use of prolonged two-week depuration on V. vulnificus populations in Gulf Coast oysters. The study evaluated the impact of prolonged depuration on V. vulnificus fatty acid profile change and the ability to survive in simulated gastric fluid. Oyster depuration in seawater (10 or 22oC, 14 days) reduced V. vulnificus counts, but not to non-detectable level, indicating close ecological relationship between the pathogen and mollusk. Greatest V. vulnificus count reductions were seen in 12 ppt 10°C seawater (2.7 log10 CFU/g) and in 20 ppt 22°C seawater (2.8 logs). Mesophilic vibrios dominated the overall microflora of freshly harvested oysters, while refrigeration selected for psychrotrophic bacteria. Depuration at 22°C retained dominance of mesophilic vibrios, including pathogenic species. Although aerobic plate counts were lower in 22°C depurated oysters (5.0 logs vs 6.0 logs), depuration at 10°C had little to no advantage over 22°C in terms of vibrio population reduction. Use of prolonged depuration remains economically questionable since this method failed to completely eliminate V. vulnificus. Starved V. vulnificus behavior in artificial seawater showed that low temperature (4oC) and high seawater salinity (35 ppt) contributed to pathogen population reduction. Starved V. vulnificus did not adjust membrane fluidity to storage temperature within the investigated time frame. However, a significant fatty acid switch from C18:1w7c to C18:1w6c by double bond relocation was observed. The relocation was faster at ambient temperatures compared to refrigerated temperatures. The majority of V. vulnificus foodborne infections occur during warm summer months. Vibrio vulnificus ATCC 27562 was significantly less resistant (3.7 min D-value) to simulated gastric fluid (pH 4.0) after 7-day storage at 4oC compared to the control (7.8 min D-value). Therefore, greater gastric fluid sensitivity of the pathogen may occur in winter-harvested oysters and may partially explain the low number of winter outbreaks.
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A mathematical framework for designing and evaluating control strategies for water- & food-borne pathogens : a norovirus case studyMcMenemy, Paul January 2017 (has links)
Norovirus (NoV) is a significant cause of gastroenteritis globally, and the consumption of oysters is frequently linked to outbreaks. Depuration is the principle means employed to reduce levels of potentially harmful agents or toxins in shellfish. The aim of this thesis is to construct mathematical models which can describe the depuration dynamics of water-borne pathogens, and specifically examine the dynamics of NoV during depuration for a population shellfish. Legislation is currently under consideration within the EU by the Directorate-General for Health and Consumers (DG SANCO) to limit the maximum level of NoV that consumers are exposed to via this route. Therefore it is important to the utility of the thesis that any models constructed should incorporate control measures which could be used to implement minimum NoV levels. Doing so allowed calculation of minimum depuration times that would be required to adhere to the control measures incorporated into the models. In addition to modelling the impact on pathogens during the depuration, we wished to gain some insight into how the variability, and not just the mean levels, of water-borne pathogens can be as important with respect to the length of depuration required to minimise any food safety risks to the consumer. This proved difficult in the absence of any data sets that can be used to calculate variability measures, as little data is currently available to inform these values for NoV. However, our modelling techniques were able to calculate an upper limit on the variability of water-borne pathogens that can be well approximated by lognormal distributions. Finally we construct a model which provided linkage between the depuration process and the accretion of pathogens by shellfish while still within farming waters. This model proposed that the pulses of untreated waste waters released by sewage treatment works due to high levels of rainfall would be transmitted into shellfish whilst filter-feeding.
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Biomagnificação do heptacloro num modelo de simulação em condições ex-situ / Biomagnification of heptacloro in a model of simulation in former-situ conditionsMaranho, Lucineide Aparecida 12 April 2006 (has links)
Os estudos realizados em diversas partes do mundo sobre a utilização de pesticidas e os impactos que estes podem causar ao ambiente são uma das ações prioritárias para o desenvolvimento da agricultura, principalmente para aqueles pesticidas que são persistentes ao meio biótico e abiótico, como o inseticida heptacloro, que apesar de seu uso restrito para tratamento de madeira, ainda é muito usado no Brasil clandestinamente para outros fins. A maioria dos estudos realizados até agora sobre biomagnificação envolve o meio terrestre e uma pequena porcentagem desses é direcionada para o meio aquático e tem sido realizada em modelos de campo. O objetivo deste projeto foi determinar a CL50 96 horas para peixes a acumulação, biomagnificação e depuração do heptacloro em um modelo de sistema aquático. Como não existe nenhuma norma que defina o efeito cumulativo através dos níveis tróficos, pretendeu-se com esta pesquisa estimar a biomagnificação e depuração do heptacloro. Este estudo foi realizado em laboratório, em um modelo dividido em compartimentos individualizados, no qual somente as algas (Pseudokirchneriella subcapitata) foram submetidas por um período de 7 dias ao heptacloro, obtendo-se uma concentração final de 0,10 x 10-5µg heptacloro/µg algas, as quais posteriormente serviram de alimento para os microcrustáceos (Daphnia magna) durante 9 dias, que ao final concentraram 0,12 x 10-5 µg heptacloro/µg organismos. Por último, os peixes (Danio rerio) foram alimentados com microcrustáceos, no período de 5 dias, alcançando uma concentração final de 0,62 x 10-8 µg heptacloro/µg organismos. Nos últimos 9 dias, durante o período de depuração, os peixes foram alimentados em dias intercalados com microcrustáceos e ração sem contaminação com o produto, atingindo uma concentração final de 0,25 x 10-8 µg heptacloro/µg organismos. Nos testes realizados com esses três organismos, observou-se que a concentração ficou maior conforme o nível dentro do modelo proposto era mais alto, comprovando assim a hipótese do poder de bioacumulação, biomagnificação e depuração do heptacloro. / The studies carried out in different parts of the world about the pesticides use and the impacts that they can cause to the environment, are one of the priority actions for the agriculture development, mainly for those pesticides that are persistents in the biotic and abiotic environment, such as the heptachlor insecticide, which is still illegally used for others purposes in Brazil, although its use is limited for the wood treatment. The majority of the studies carried out until now about biomagnification involves the terrestrial environment and a small percentage of these studies are directed for the aquatic environment, and this small percentage has been carried out in field models. The aim of this project was to determine the LC50 96 hours for fish, accumulation, biomagnifications, and depuration of heptachlor in an aquatic system model and, as there isn?t any norm that defines the cumulative effect through trophic levels, it was claimed with this research to esteem the heptachlor biomagnification and depuration. This study was carried out in a laboratory, in a model divided in single chambers, in which the algae (Pseudokirchneriella subcapitata were submitted during 7 days to the heptaclhor, getting a final concentration of 0.10 x 10-5µg heptaclhor/µg algae, which was later served as food for the microcrustaceans (Daphnia magna) were submitted during 7 days to the heptaclhor, getting a final concentration of 0.10 x 10-5Mµg heptaclhor/µg algae, which was later served as food for the microcrustaceans (Daphnia magna) were fed with microcrustaceans, in the period of 5 days, reaching a final concentration of 0.62 x 10-8 µg heptaclhor/µg organisms. In the last 9 days, during the period of depuration, the fish were fed in days intercalated with microcrustaceans and ration without contamination with the product, reaching a final concentration of 0.25 x 10-8 µg heptacloro/µg organisms. In tests carried out with these three organisms, it was observed that the concentration was bigger as higher the level inside of the considered model, thus proving the hypothesis of the bioaccumulation, biomagnification, and depuration power of heptachlor.
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Sistema óptico baseado em visão computacional para obtenção de níveis de turbulência na superfície de escoamentos livres com aplicação na determinação de parâmetros relacionados com a reoxigenação do meio líquido / Optical system based on machine vision for measurement of surface turbulence level in open flow with application on determination of parameters related to reaeration of the liquid phaseSzéliga, Marcos Rogério 12 September 2003 (has links)
O sistema óptico baseado em Visão Computacional, consiste em dispositivos de geração, aquisição e processamento das imagens da incidência de um feixe laser sobre a superfície de um escoamento e reflexão sobre uma tela horizontal. Com função de medição da turbulência na superfície do fluxo, os dispositivos de geração e aquisição de imagens foram condicionados sobre um tanque de produção hidrodinâmica de turbulência, acionado por grades oscilantes. Um software, com interface gráfica, foi desenvolvido para processamento das imagens e obtenção de dados geométricos do escoamento. Com até 30 quadros por segundo é possível visualizar a oscilação turbulenta e também as superfícies 3D, equivalentes ao escoamento real, geradas numa malha de diferenças finitas. Obtêm-se velocidades verticais, ampliações superficiais e velocidades angulares, entre outros parâmetros, em diversas situações de turbulência. No mesmo tanque foram procedidas, previamente, medidas de concentração de oxigênio dissolvido segundo uma técnica que permite determinar o coeficiente de reaeração K2. Em modelo gráfico foram reunidos dados de turbulência e coeficientes K2 de forma a possibilitar a previsão desse coeficiente em escoamentos naturais, com aplicação na estimativa da capacidade de autodepuração nos corpos d\'água receptores de efluentes, que sofrem rebaixamento do nível de oxigênio. / The optical system based on machine vision consists on generation, acquisition and processing devices of the images of a laser beam incidence on a flow surface and reflection on a horizontal screen. To measure the turbulence in the surface flow, the generation and acquisition of images devices were conditioned on a tank of hydrodynamic turbulence production by oscillating grids. Software, with graphic interface, was developed for processing the images and obtaining geometric data of the flow. With up to 30 pictures per second it is possible to visualize the turbulent oscillation and also the 3D surfaces, equivalent to the real flow, generated in a mesh of finite differences. Vertical velocities, surface enlargements and angular velocities are obtained, among other parameters, in several turbulence situations. In the same tank were proceeded, previously, measures of concentration of dissolved oxygen according to a technique that allows to determine the reaeration coefficient K2. Turbulence data and coefficients K2 were gathered in a graphic model to make possible the forecast of this coefficient in natural flows, with application on the estimation of the natural depuration capability in the receiving water bodies of inflows, that suffer lowering of the oxygen level.
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Low-temperature post-harvest processing for reducing Vibrio parahaemolyticus and Vibrio vulnificus in raw oystersChae, Minjung 29 June 2007 (has links)
Oysters are filter-feeding bivalves, which filter water for nutrients and often accumulate contaminants and human pathogens such as Vibrio parahaemolyticus and Vibrio vulnificus naturally occurring in the marine environment. These naturally occurring pathogens have been frequently isolated from raw shellfish, particularly oyster, in the United States and are recognized as the leading causes of human gastroenteritis associated with seafood consumption. Human illness caused by consumption of raw oyster contaminated with V. parahaemolyticus and Vibrio vulnificus typically results in reduced sales of oysters and a consequent significant financial burden for the producers. The United States produces more than 27 million pounds of oysters each year with a large portion of them being produced from the coastal water of the Gulf of Mexico. It is estimated that 20 million Americans eat raw shellfish and consumption of raw oyster
is responsible for about 95% of all deaths associated with seafood consumption in the U.S., making raw oysters one of the most hazardous seafoods. Several post-harvest processes, including low temperature pasteurization, freezing, high pressure processing and irradiation, have been reported capable of reducing Vibrio contamination in raw oysters. However, most of them require either a significant amount of initial investment or operation costs, and oysters are often killed during processing. Cost-effective post-harvest processing for reducing V. parahaemolyticus in raw oysters without significant adverse effects on the oysters remains to be developed. This study was conducted to determine impacts of low-temperature (15, 10 and 5°C) depuration and frozen storage on reducing V. parahaemolyticus and V. vulnificus in raw oysters. Depuration of the Gulf oyster (Crassostrea virginica) with electrolyzed oxidizing (EO) water (chlorine, 30 ppm; pH 2.82; oxidation-reduction potential, 1,131mV) containing 3% NaCl was found ineffective on reducing both V. parahaemolyticus and V. vulnificus in the oysters. Reductions of V. parahaemolyticus and V. vulnificus in oyster after 48 h of EO water depuration at 22°C were limited to 0.7 and 1.4 log MPN/g, respectively. Depuration with EO water at lower temperatures did not enhance reductions of Vibrio in the oysters. Greater reductions of V. parahaemolyticus (1.2 log MPN/g) and V. vulnificus (2.0 log MPN/g) were observed when the oysters were depurated with artificial seawater (ASW) at room temperature (22°C) for 48 h. Decreasing temperature of ASW to 15°C for depuration significantly increased the reductions of V. parahaemolyticus and V. vulnificus to 2.1 and 2.9 log MPN/g, respectively, after 48 h of process. However, depuration of oyster in ASW at 10 and 5°C were found less effective than at 15°C in reducing Vibrio in
the Gulf oysters. An extended depuration with ASW at 15°C for 96 h was capable of achieving 2.6 and 3.3 log MPN/g of reductions of V. parahaemolyticus and V. vulnificus, respectively, in the Gulf oysters. Study of effects of frozen storage at -10, -23 and -30°C on reducing V. parahaemolyticus in raw half-shell Pacific oyster (Crassostrea gigas) found that the population of the bacterium decreased faster in oysters stored at -10 than at -23 or -30°C. Holding half-shell Pacific oyster at -10°C for three months or at -23°C for four months was capable of achieving a greater than 3-log (MPN/g) reduction of V. parahaemolyticus in the Pacific oyster. / Graduation date: 2008
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ValoraÃÃo dos serviÃos ambientais associada à autodepuraÃÃo da Ãgua do rio Jaguaribe-CE em um CenÃrio de mudanÃas climÃticas. / Valuation of ecosystem services associated with self-purification of river water Jaguaribe-EC in a climate change scenario.RogÃrio Soliani Studart 30 August 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A poluiÃÃo dos recursos hÃdricos, principalmente, decorrente do lanÃamento de esgotos
domÃsticos sem tratamento ou de sistema de coleta deficitÃrio, gera graves prejuÃzos ao
desenvolvimento sÃcioeconÃmico, afetando significativamente a qualidade de vida da
populaÃÃo. No Brasil, a coleta e tratamento de esgoto sanitÃrio sÃo considerados precÃrios.
O Plano de Gerenciamento das Ãguas da Bacia do Jaguaribe (SRH, 1999) apontou o
esgoto domÃstico como uma das principais fontes poluidoras da bacia, dado que poucas
cidades na bacia possuem sistema pÃblico de coleta e tratamento de esgoto. Sendo assim,
pode-se afirmar, sem sombra de dÃvida, que os centros urbanos na Bacia do Jaguaribe sÃo
potenciais poluidores dos seus corpos hÃdricos por esgotos domÃsticos, em virtude da nÃo
existÃncia de sistema adequado de coleta, tratamento e despejo final de seus efluentes nos
corpos receptores. Observa-se, portanto, a importÃncia fundamental do serviÃo ambiental
prestado pelo Rio Jaguaribe e seus afluentes na diluiÃÃo e na autodepuraÃÃo das cargas
orgÃnicas que a eles sÃo destinadas. A precificaÃÃo deste serviÃo ambiental induzirà os
agentes econÃmicos a calcularem a relaÃÃo custo-benefÃcio, caso queiram utilizÃ-lo. Nesta
pesquisa, o custo do serviÃo ambiental prestado pelo Rio Jaguaribe foi estimado pelos
custos com a instalaÃÃo de estaÃÃes de tratamento de esgotos (lagoas de estabilizaÃÃo),
implantadas no Estado do CearÃ, entre os anos de 2008 e 2010. Foi realizada simulaÃÃo
com o modelo numÃrico QUAL2BR. O valor total do tratamento estimado para o cenÃrio
atual (2010) foi de R$ 5.658.365,92. Este à o custo que, teoricamente, à fornecido,
gratuitamente, pelo Rio Jaguaribe pelos serviÃos ambientais de autodepuraÃÃo e de diluiÃÃo
das cargas poluidoras dos efluentes. Outra analise que se fez, foi analisar o impacto das
mudanÃas climÃticas na autodepuraÃÃo do corpo hÃdrico (em termos de DBO) usando dois
modelos de mudanÃa climÃtica: o HadGEM2-AO e o CanESM2. / The pollution of water resources, mainly arising from the release of untreated
domestic sewage collection system or deficit, raises serious damage to the socioeconomic
development, significantly affecting the quality of life. In Brazil, the
collection and treatment of sewage are considered precarious. The Management
Plan Basin Water Jaguaribe (SRH, 1999) pointed domestic sewage as a major
pollution sources in the basin, given that few cities in the basin have public
collection system and wastewater treatment. Thus, one can say without a doubt that
urban centers in Jaguaribe Basin are potential polluters of their water bodies by
domestic sewage, because of lack of adequate system of collection, treatment and
final disposal of their effluents in receiving bodies. There are, therefore, the
fundamental importance of the environmental service provided by Jaguaribe River
and its tributaries dilution and self-purification of organic loads that they are
intended. The pricing of this service environment will induce economic agents to
calculate the cost-benefit, if they want to use it. In this research, the cost of the
environmental service provided by Jaguaribe River was estimated costs for the
installation of sewage treatment plants (stabilization ponds), implemented in the
State of CearÃ, between the years 2008 and 2010. Simulation was performed with
the numerical model QUAL2BR. The total estimated remediation costs for the
current scenario (2010) was R$ 5.658.365,92. This is the cost that theoretically is
provided free of charge by Jaguaribe River the environmental services of selfpurification
and dilution of the pollutant effluent. Another analysis that was done,
was to analyze the impact of climate change in the self-purification of the water
body (in terms of BOD) using two models of climate change: the HadGEM2-AO
and CanESM2.
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Biomagnificação do heptacloro num modelo de simulação em condições ex-situ / Biomagnification of heptacloro in a model of simulation in former-situ conditionsLucineide Aparecida Maranho 12 April 2006 (has links)
Os estudos realizados em diversas partes do mundo sobre a utilização de pesticidas e os impactos que estes podem causar ao ambiente são uma das ações prioritárias para o desenvolvimento da agricultura, principalmente para aqueles pesticidas que são persistentes ao meio biótico e abiótico, como o inseticida heptacloro, que apesar de seu uso restrito para tratamento de madeira, ainda é muito usado no Brasil clandestinamente para outros fins. A maioria dos estudos realizados até agora sobre biomagnificação envolve o meio terrestre e uma pequena porcentagem desses é direcionada para o meio aquático e tem sido realizada em modelos de campo. O objetivo deste projeto foi determinar a CL50 96 horas para peixes a acumulação, biomagnificação e depuração do heptacloro em um modelo de sistema aquático. Como não existe nenhuma norma que defina o efeito cumulativo através dos níveis tróficos, pretendeu-se com esta pesquisa estimar a biomagnificação e depuração do heptacloro. Este estudo foi realizado em laboratório, em um modelo dividido em compartimentos individualizados, no qual somente as algas (Pseudokirchneriella subcapitata) foram submetidas por um período de 7 dias ao heptacloro, obtendo-se uma concentração final de 0,10 x 10-5µg heptacloro/µg algas, as quais posteriormente serviram de alimento para os microcrustáceos (Daphnia magna) durante 9 dias, que ao final concentraram 0,12 x 10-5 µg heptacloro/µg organismos. Por último, os peixes (Danio rerio) foram alimentados com microcrustáceos, no período de 5 dias, alcançando uma concentração final de 0,62 x 10-8 µg heptacloro/µg organismos. Nos últimos 9 dias, durante o período de depuração, os peixes foram alimentados em dias intercalados com microcrustáceos e ração sem contaminação com o produto, atingindo uma concentração final de 0,25 x 10-8 µg heptacloro/µg organismos. Nos testes realizados com esses três organismos, observou-se que a concentração ficou maior conforme o nível dentro do modelo proposto era mais alto, comprovando assim a hipótese do poder de bioacumulação, biomagnificação e depuração do heptacloro. / The studies carried out in different parts of the world about the pesticides use and the impacts that they can cause to the environment, are one of the priority actions for the agriculture development, mainly for those pesticides that are persistents in the biotic and abiotic environment, such as the heptachlor insecticide, which is still illegally used for others purposes in Brazil, although its use is limited for the wood treatment. The majority of the studies carried out until now about biomagnification involves the terrestrial environment and a small percentage of these studies are directed for the aquatic environment, and this small percentage has been carried out in field models. The aim of this project was to determine the LC50 96 hours for fish, accumulation, biomagnifications, and depuration of heptachlor in an aquatic system model and, as there isn?t any norm that defines the cumulative effect through trophic levels, it was claimed with this research to esteem the heptachlor biomagnification and depuration. This study was carried out in a laboratory, in a model divided in single chambers, in which the algae (Pseudokirchneriella subcapitata were submitted during 7 days to the heptaclhor, getting a final concentration of 0.10 x 10-5µg heptaclhor/µg algae, which was later served as food for the microcrustaceans (Daphnia magna) were submitted during 7 days to the heptaclhor, getting a final concentration of 0.10 x 10-5Mµg heptaclhor/µg algae, which was later served as food for the microcrustaceans (Daphnia magna) were fed with microcrustaceans, in the period of 5 days, reaching a final concentration of 0.62 x 10-8 µg heptaclhor/µg organisms. In the last 9 days, during the period of depuration, the fish were fed in days intercalated with microcrustaceans and ration without contamination with the product, reaching a final concentration of 0.25 x 10-8 µg heptacloro/µg organisms. In tests carried out with these three organisms, it was observed that the concentration was bigger as higher the level inside of the considered model, thus proving the hypothesis of the bioaccumulation, biomagnification, and depuration power of heptachlor.
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Sistema óptico baseado em visão computacional para obtenção de níveis de turbulência na superfície de escoamentos livres com aplicação na determinação de parâmetros relacionados com a reoxigenação do meio líquido / Optical system based on machine vision for measurement of surface turbulence level in open flow with application on determination of parameters related to reaeration of the liquid phaseMarcos Rogério Széliga 12 September 2003 (has links)
O sistema óptico baseado em Visão Computacional, consiste em dispositivos de geração, aquisição e processamento das imagens da incidência de um feixe laser sobre a superfície de um escoamento e reflexão sobre uma tela horizontal. Com função de medição da turbulência na superfície do fluxo, os dispositivos de geração e aquisição de imagens foram condicionados sobre um tanque de produção hidrodinâmica de turbulência, acionado por grades oscilantes. Um software, com interface gráfica, foi desenvolvido para processamento das imagens e obtenção de dados geométricos do escoamento. Com até 30 quadros por segundo é possível visualizar a oscilação turbulenta e também as superfícies 3D, equivalentes ao escoamento real, geradas numa malha de diferenças finitas. Obtêm-se velocidades verticais, ampliações superficiais e velocidades angulares, entre outros parâmetros, em diversas situações de turbulência. No mesmo tanque foram procedidas, previamente, medidas de concentração de oxigênio dissolvido segundo uma técnica que permite determinar o coeficiente de reaeração K2. Em modelo gráfico foram reunidos dados de turbulência e coeficientes K2 de forma a possibilitar a previsão desse coeficiente em escoamentos naturais, com aplicação na estimativa da capacidade de autodepuração nos corpos d\'água receptores de efluentes, que sofrem rebaixamento do nível de oxigênio. / The optical system based on machine vision consists on generation, acquisition and processing devices of the images of a laser beam incidence on a flow surface and reflection on a horizontal screen. To measure the turbulence in the surface flow, the generation and acquisition of images devices were conditioned on a tank of hydrodynamic turbulence production by oscillating grids. Software, with graphic interface, was developed for processing the images and obtaining geometric data of the flow. With up to 30 pictures per second it is possible to visualize the turbulent oscillation and also the 3D surfaces, equivalent to the real flow, generated in a mesh of finite differences. Vertical velocities, surface enlargements and angular velocities are obtained, among other parameters, in several turbulence situations. In the same tank were proceeded, previously, measures of concentration of dissolved oxygen according to a technique that allows to determine the reaeration coefficient K2. Turbulence data and coefficients K2 were gathered in a graphic model to make possible the forecast of this coefficient in natural flows, with application on the estimation of the natural depuration capability in the receiving water bodies of inflows, that suffer lowering of the oxygen level.
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