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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.
41

An Internship with the Ohio River Valley Water Sanitation Commission: Monitoring Water Quality through Biological Communities

Phirman, Daniel J. 27 April 2005 (has links)
No description available.
42

Towards a System for Nanosecond-Gated, Fluorescence Based Monitoring of Cellular Responses to High Hydrostatic Pressures

Long, Zachary C. 14 August 2013 (has links)
No description available.
43

Impact of Specific Acid Mine Drainage Contaminants on Macroinvertebrate Communities in Southeastern Ohio Streams

Last, Jennifer L. 07 December 2001 (has links)
No description available.
44

Um estudo crítico sobre a saúde dos trabalhadores de galvânicas, por meio das relações entre as avaliações ambientais, biológicas e otorrinolaringológicas / A study relating to electroplaters´ health through relationships between environmental, biological, nose and throat evaluations

Silva, Carlos Sergio da 22 September 1997 (has links)
Avaliação ambiental, biológica e otorrinolaringológica foi realizada em 461 trabalhadores de 22 galvânicas com diferentes processos de tratamento de superficie: anodização, cromo duro, cromo decorativo, zincagem e processos diversos. O ar do ambiente de trabalho foi coletado individualmente e em pontos fixos, durante a semana de trabalho, para se avaliarem névoas sulfúricas e clorídricas, além daquelas referentes a cromo, níquel e zinco. Amostras de urina dos trabalhadores, foram coletadas no início e final do período de trabalho, para se determinar a concentração de Cr-U, Ni-U e Zn-U. Utilizou-se a técnica de espectrofotometria de absorção atômica com forno de grafite para determinação de Cr-U e Ni-U; o Zn-ar, Ni-ar e o Zn-U foram determinados pela mesma técnica mas utilizando-se na atomização do analito, a chama. Os limites de detecção foram semelhantes aos encontrados na literatura internacional. Os resultados ambientais situaram-se, na sua maioria, bem abaixo dos limites de tolerância estabelecido pela legislação brasileira e internacional, ressaltando-se que, dos contaminantes avaliados, existem LTs apenas para o cromo e névoas clorídricas enquanto que limite biológico apenas para o Cr-U. Os resultados otorrinolaringológicos dos trabalhadores foram surpreendentes, considerando-se todos os processos avaliados: 35,5% de lesões médias e avançadas nas vias aéreas superiores e 40,1% de lesões iniciais e inespecíficas. Estes resultados relacionados com os obtidos nas avaliações ambientais e biológicas, dão-nos a certeza de que os limites de tolerância não são parâmetros seguros para proteger a saúde do trabalhador. / Environmental, biological, and otolaryngology evaluations were carried out on 461 workers from 22 electroplaters with different processes for the treatment of surfaces. Air from the working environment was collected both individually end from fixed points, during the working week, for evaluation of sulphuric and hydrochloric acid mists, as well as for mists of chrome, nickel and zinc. Samples of worker\'s urine were collected at the beginning and end of the work shift in order to determine the concentrations of U-Cr, U-Ni and U-Zn. Electrothermal atomic absorption spectrometry was used to determine air-Cr, U-Cr, and U-Ni; air-Zn, air-Ni and U-Zn were determined using the atomic absorption spectrometry. The detection limits were similar to those found in the intemational literature. The environmental and biological results were in most cases below the limits set by the Brazilian and International legislation. Note that, of the contaminants evaluated, TLs are available for only chrome and hydrochloric acid mists and Biological Limits for only U-Cr. The otolaryngology results for the workers were surprising, taking into account all of the processes evaluated: 35.5% with medium and advanced lesions of the upper respiratory tract, and 40.1% with initial or non-specific lesions. These results, taken together with those obtained in the environmental and biological evaluations show that the tolerance limits are not safe parameters to protect worker\'s health.
45

Avaliação dos indicadores biológicos de exposição aos metais em trabalhadores de fundições / Evaluation of biological indicators of exposure to metals in foundry workers

Santos, Claudia Regina dos 07 December 2004 (has links)
A produção de metais sanitários é um setor em constante fase de crescimento no país. O processo industrial envolve etapas como a evaporação, condensação e oxidação dos metais no ar que levam a formação de fumos metálicos em vários tipos de indústria, inclusive em fundições. A exposição do trabalhador ao ambiente contaminado pode levar ao aparecimento de alterações bioquímicas e, em algumas circunstâncias, de doenças profissionais. No setor de metais sanitários, são utilizadas ligas metálicas de latão, onde predomina o zinco e o cobre, sendo o chumbo, cádmio, manganês e níquel, metais que aparecem sob a forma de impurezas. Desses metais, apenas o chumbo sanguíneo (Pb-S) e o cádmio urinário (Cd-U) são regulamentados no Brasil, de acordo com a NR-7 do Ministério do Trabalho, como indicadores biológicos de exposição. No presente estudo, foram otimizados e validados métodos para a determinação de Pb-S, Cd-U, Mn-U e Ni-U por espectrometria de absorção atômica acoplado a forno de grafite. Posteriormente foram avaliados 273 indivíduos do sexo masculino (178 do grupo exposto e 95 do grupo controle) que trabalhavam em 8 fundições de metais sanitários de Loanda-PR. Os níveis de Pb-S apresentaram-se elevados, considerando o limite internacional. Os metais avaliados na urina Cd-U, Mn-U e Ni-U apresentaram concentrações relativamente baixas, sendo considerado o chumbo como o principal problema, relacionado aos fumos metálicos. Foram propostas medidas corretivas nos ambientes de trabalho e os níveis dos quatro metais em questão foram reavaliados em dois períodos diferentes (antes e após as modificações), apresentando no segundo momento reduções estatisticamente significativas. As médias observadas nos dois períodos foram de 42,74&#181;g/dL e 26,54&#181;g/dL para o Pb-S; 0,269 e 0,015&#181;g/g de creatinina para o Cd-U; 1,94 e 0,39&#181;g/g de creatinina para o Mn-U e 1,82 e 0,68&#181;g/g de creatinina para o Ni-U, com níveis de significância (p) < 0,05, evidenciando assim a importância da adequação do ambiente de trabalho na garantia de exposições seguras para o trabalhador. / The sanitary metal production is a sector in constant development in Brazil. This industrial process involves stages such as evaporation, condensation and oxidation of metals, therefore allowing the formation of metallic fumes in some types of industry, and also in foundries. The contaminated environment can induce, in the workers, biochemical alterations and, in some circumstances, occupational diseases. In the sanitary metal sector, alloys are used in which predominate the metals zinc and copper, being lead, cadmium, manganese and nickel, metals that can be found in the form of impurities. According to Brazilian legislation\'s (Ministry of Work) only lead in blood and cadmium in urine are regulated as biological monitoring of exposure. In the present study, methods based on graphite furnace atomic absorption spectrometry and zeeman background correction were validated for quantification of Pb-B, Cd-U, Mn-U and Ni-U, and 273 male individuais (178 exposed group and 95 non exposed - control group), working in 8 sanitary metal foundries, in Loanda, Paraná, a state located in the south of Brazil, were evaluated. The levels of Pb-B were higher than the international permissible limit. Relatively low concentrations were found for the other evaluated metals: Cd-U, Mn-U and Ni-U, thus lead can be considered, in this case, the main problem, associated with metallic fumes. Corrective measures in the work environment were proposed and implemented, thus the four metais were evaluated in two distinct situations (biological determinations were done before and after the modifications). The results of the second evaluation showed reductions those were statistically significant. The means obtained in the two determinations were 42,74&#181;g/dL and 26,54&#181;g/dL for Pb-B; 0,269 and 0,015&#181;g/g creatinine for Cd-U; 1,94 and 0,39&#181;g/g creatinine for Mn-U and 1,82 and 0,68&#181;g/g creatinine for Ni-U, with leveis of significance (p) < 0,05, thus evidencing the importance of the adequacy of the work environment in the guarantee of safe exposures for the workers.
46

Avaliação dos indicadores biológicos de exposição aos metais em trabalhadores de fundições / Evaluation of biological indicators of exposure to metals in foundry workers

Claudia Regina dos Santos 07 December 2004 (has links)
A produção de metais sanitários é um setor em constante fase de crescimento no país. O processo industrial envolve etapas como a evaporação, condensação e oxidação dos metais no ar que levam a formação de fumos metálicos em vários tipos de indústria, inclusive em fundições. A exposição do trabalhador ao ambiente contaminado pode levar ao aparecimento de alterações bioquímicas e, em algumas circunstâncias, de doenças profissionais. No setor de metais sanitários, são utilizadas ligas metálicas de latão, onde predomina o zinco e o cobre, sendo o chumbo, cádmio, manganês e níquel, metais que aparecem sob a forma de impurezas. Desses metais, apenas o chumbo sanguíneo (Pb-S) e o cádmio urinário (Cd-U) são regulamentados no Brasil, de acordo com a NR-7 do Ministério do Trabalho, como indicadores biológicos de exposição. No presente estudo, foram otimizados e validados métodos para a determinação de Pb-S, Cd-U, Mn-U e Ni-U por espectrometria de absorção atômica acoplado a forno de grafite. Posteriormente foram avaliados 273 indivíduos do sexo masculino (178 do grupo exposto e 95 do grupo controle) que trabalhavam em 8 fundições de metais sanitários de Loanda-PR. Os níveis de Pb-S apresentaram-se elevados, considerando o limite internacional. Os metais avaliados na urina Cd-U, Mn-U e Ni-U apresentaram concentrações relativamente baixas, sendo considerado o chumbo como o principal problema, relacionado aos fumos metálicos. Foram propostas medidas corretivas nos ambientes de trabalho e os níveis dos quatro metais em questão foram reavaliados em dois períodos diferentes (antes e após as modificações), apresentando no segundo momento reduções estatisticamente significativas. As médias observadas nos dois períodos foram de 42,74&#181;g/dL e 26,54&#181;g/dL para o Pb-S; 0,269 e 0,015&#181;g/g de creatinina para o Cd-U; 1,94 e 0,39&#181;g/g de creatinina para o Mn-U e 1,82 e 0,68&#181;g/g de creatinina para o Ni-U, com níveis de significância (p) < 0,05, evidenciando assim a importância da adequação do ambiente de trabalho na garantia de exposições seguras para o trabalhador. / The sanitary metal production is a sector in constant development in Brazil. This industrial process involves stages such as evaporation, condensation and oxidation of metals, therefore allowing the formation of metallic fumes in some types of industry, and also in foundries. The contaminated environment can induce, in the workers, biochemical alterations and, in some circumstances, occupational diseases. In the sanitary metal sector, alloys are used in which predominate the metals zinc and copper, being lead, cadmium, manganese and nickel, metals that can be found in the form of impurities. According to Brazilian legislation\'s (Ministry of Work) only lead in blood and cadmium in urine are regulated as biological monitoring of exposure. In the present study, methods based on graphite furnace atomic absorption spectrometry and zeeman background correction were validated for quantification of Pb-B, Cd-U, Mn-U and Ni-U, and 273 male individuais (178 exposed group and 95 non exposed - control group), working in 8 sanitary metal foundries, in Loanda, Paraná, a state located in the south of Brazil, were evaluated. The levels of Pb-B were higher than the international permissible limit. Relatively low concentrations were found for the other evaluated metals: Cd-U, Mn-U and Ni-U, thus lead can be considered, in this case, the main problem, associated with metallic fumes. Corrective measures in the work environment were proposed and implemented, thus the four metais were evaluated in two distinct situations (biological determinations were done before and after the modifications). The results of the second evaluation showed reductions those were statistically significant. The means obtained in the two determinations were 42,74&#181;g/dL and 26,54&#181;g/dL for Pb-B; 0,269 and 0,015&#181;g/g creatinine for Cd-U; 1,94 and 0,39&#181;g/g creatinine for Mn-U and 1,82 and 0,68&#181;g/g creatinine for Ni-U, with leveis of significance (p) < 0,05, thus evidencing the importance of the adequacy of the work environment in the guarantee of safe exposures for the workers.
47

Um estudo crítico sobre a saúde dos trabalhadores de galvânicas, por meio das relações entre as avaliações ambientais, biológicas e otorrinolaringológicas / A study relating to electroplaters´ health through relationships between environmental, biological, nose and throat evaluations

Carlos Sergio da Silva 22 September 1997 (has links)
Avaliação ambiental, biológica e otorrinolaringológica foi realizada em 461 trabalhadores de 22 galvânicas com diferentes processos de tratamento de superficie: anodização, cromo duro, cromo decorativo, zincagem e processos diversos. O ar do ambiente de trabalho foi coletado individualmente e em pontos fixos, durante a semana de trabalho, para se avaliarem névoas sulfúricas e clorídricas, além daquelas referentes a cromo, níquel e zinco. Amostras de urina dos trabalhadores, foram coletadas no início e final do período de trabalho, para se determinar a concentração de Cr-U, Ni-U e Zn-U. Utilizou-se a técnica de espectrofotometria de absorção atômica com forno de grafite para determinação de Cr-U e Ni-U; o Zn-ar, Ni-ar e o Zn-U foram determinados pela mesma técnica mas utilizando-se na atomização do analito, a chama. Os limites de detecção foram semelhantes aos encontrados na literatura internacional. Os resultados ambientais situaram-se, na sua maioria, bem abaixo dos limites de tolerância estabelecido pela legislação brasileira e internacional, ressaltando-se que, dos contaminantes avaliados, existem LTs apenas para o cromo e névoas clorídricas enquanto que limite biológico apenas para o Cr-U. Os resultados otorrinolaringológicos dos trabalhadores foram surpreendentes, considerando-se todos os processos avaliados: 35,5% de lesões médias e avançadas nas vias aéreas superiores e 40,1% de lesões iniciais e inespecíficas. Estes resultados relacionados com os obtidos nas avaliações ambientais e biológicas, dão-nos a certeza de que os limites de tolerância não são parâmetros seguros para proteger a saúde do trabalhador. / Environmental, biological, and otolaryngology evaluations were carried out on 461 workers from 22 electroplaters with different processes for the treatment of surfaces. Air from the working environment was collected both individually end from fixed points, during the working week, for evaluation of sulphuric and hydrochloric acid mists, as well as for mists of chrome, nickel and zinc. Samples of worker\'s urine were collected at the beginning and end of the work shift in order to determine the concentrations of U-Cr, U-Ni and U-Zn. Electrothermal atomic absorption spectrometry was used to determine air-Cr, U-Cr, and U-Ni; air-Zn, air-Ni and U-Zn were determined using the atomic absorption spectrometry. The detection limits were similar to those found in the intemational literature. The environmental and biological results were in most cases below the limits set by the Brazilian and International legislation. Note that, of the contaminants evaluated, TLs are available for only chrome and hydrochloric acid mists and Biological Limits for only U-Cr. The otolaryngology results for the workers were surprising, taking into account all of the processes evaluated: 35.5% with medium and advanced lesions of the upper respiratory tract, and 40.1% with initial or non-specific lesions. These results, taken together with those obtained in the environmental and biological evaluations show that the tolerance limits are not safe parameters to protect worker\'s health.
48

Assessing the Effectiveness of the Roaring Branch BMP Retrofit Using Macroinvertebrate Bioassessment

Banning, James L 01 February 2010 (has links)
Using benthic macroinvertebrates to measure stream health has been widely used and accepted around the world. Macroinvertebrates are resident monitors of chronic impairment in a stream since they are relatively sessile and most commonly respond to disturbance by drift but can recolonize a restored stream reach very quickly. This study tested the effectiveness of macroinvertebrate metrics developed through the Rapid Bioassessment Protocol (RBP) to detect changes in stream integrity as the result of placement of a best management practice (BMP), installed on a tributary of Roaring Branch, located in Columbus, Georgia. The BMP was designed to attenuate flow to reduce sediment suspension and downstream deposition. A sampling protocol derived from the Georgia Ecoregions Project was implemented to evaluate the macroinvertebrate community, located downstream of the BMP, and downstream of the confluence with Roaring Branch, both before and after the BMP installation. The resulting metrics were compared to a reference condition described for subecoregion 65c, sandhills-lower piedmont. A dramatic improvement or increase of macroinvertebrate populations suggests an improvement in water quality (via reduction in fine sediment deposition) due to improved physical habitat conditions for indicators (Trichoptera) of healthier streams. The results of this study suggests further restoration activities should continue and that re-evaluation of the sampling protocol should take into account a larger subsample size of benthic macroinvertebrates than currently recommended by the RBP.
49

Particules ultra-fines et santé : caractérisation des particules ultra-fines dans l'air et dans les tissus humains / Ultrafine particles and health : characterization of ultrafine particles in air and human tissues

Rinaldo, Mickaël 21 December 2015 (has links)
Les études épidémiologiques sur les effets de la fraction ultrafine de la pollution particulaire et les études sur la toxicité in vitro et in vivo des nanoparticules manufacturées témoignent d’un danger potentiel pour l’homme en raison de nouvelles propriétés physico-chimiques de la matière à l’échelle nanométrique. L’évaluation du risque lié à des expositions professionnelles ou environnementales ou le diagnostic d’un lien causal entre ces expositions et d’éventuelles pathologies peuvent être limités par l’absence de méthode de référence pour caractériser et quantifier les particules nanométriques dans les tissus et fluides biologiques. Ce travail a permis de mettre au point une méthode remplissant ces objectifs, basée sur la préparation des échantillons par digestion alcaline et microfiltration et sur l’analyse en microscopie électronique analytique. L’application de cette méthode dans deux études a permis de confirmer qu’une translocation des particules nanométriques était possible d’une part au niveau pleural avec concentration dans les black spots et d’autre part à travers le placenta avec une possible exposition du foetus. Ce travail a également permis de caractériser des sources d’expositions professionnelles ou environnementales aux particules nanométriques. Sous réserve d’optimiser le coût et le temps nécessaire pour ce type d’analyse, cette méthode pourrait permettre de définir des valeurs de référence sur des échantillons plus larges et représentatifs de la population générale ou être utilisée dans le cadre de la surveillance de travailleurs exposés. / Epidemiologic studies on the health effects of ultrafine particles from atmospheric pollution and in vitro or in vivo studies on manufactured nanoparticles toxicity suggest that potential hazards may result from new physico-chemical properties of materials at nanometric scale. To assess human health risk after occupational or environmental exposure or to demonstrate a causal relationship between such exposures and diseases may be hindered by the lack of reference method to characterize and quantify nanometric particles in biological tissues and fluids. This work allowed us to develop such a method based on samples preparation by alkaline digestion and microfiltration followed by analytical electron microscopy analysis. This method applied in two studies allowed us to confirm that pleural translocation of nanometric particles and accumulation in black spots were possible in human and that they also may pass through the placental barrier with potential fetal exposure. This work also allowed us to characterize some sources of occupational and environmental exposures. After time-cost optimization of this method, it could be used to define reference values on larger population-representative samples or used for the medical follow-up of exposed workers.
50

A BIOLOGICAL MONITORING INTERNSHIP WITH THE OHIO ENVIRONMENTAL PROTECTION AGENCY, DIVISION OF SURFACE WATER

Longsmith, Rebecca Johnson 11 January 2016 (has links)
No description available.

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