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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

Occupational exposure to ultrafine particles and polycyclic aromatic hydrocarbons from candle emissions

Silver, David J. January 2005 (has links)
Dissertation (Ph.D.)--University of South Florida, 2005. / Includes vita. Title from PDF of title page. Document formatted into pages; contains 99 pages. Includes bibliographical references.
32

Avaliação de mutagenicidade, citotoxicidade e expressão de proteínas relacionadas a apoptose, Bak, BCL-2 e P53 fosforilado, em células tratadas com fuligem e particulado total de queima de cana-de-açúcar /

Peron, Mariana Cristina Caloni. January 2006 (has links)
Orientador: Christiane Pienna Soares / Banca: Gisela de Aragão Umbuzeiro / Banca: Elza Tiemi Sakamoto Hojo / Banca: Daisy Maria Fávero Salvador / Banca: Eliana Aparecida Varanda / Resumo: O etanol obtido da cana-de-açúcar tem sido considerado um combustível alternativo. Entretanto, em países em desenvolvimento, a colheita de cana é realizada manualmente depois da queima, sendo responsável pela emissão sazonal de poluentes atmosféricos. A mutagenicidade dos resíduos de queima de cana (RQCA) e as partículas presentes na ROFA (residual oil fly ash) foram observados nos ensaios de micronúcleo em células sanguíneas de camundongos e de células mãe de grão de pólen de Tradescantia pallida (TRAC-MCN) particulado. O estudo também verificou a citotoxicidade, apoptose e genotoxicidade nas células tratadas com extrato orgânico contendo grande quantidade de HPAs e suspensão na biomassa do período de safra e entressafra. Uma alta freqüência de MN foi observada no TSP do período de safra que na entressafra e a porcentagem de células mortas foi maior em células tratadas com extrato orgânico contendo grande quantidade de HPAs e particulado. Elevada expressão de Bcl-2 e baixa expressão de p53 fosforilado foi verificado em células tratadas com extrato orgânico contendo grande quantidade de HPAs no período de safra e entressafra e em 24 e 48h pós-tratamento. É possível concluir que os HPAs presentes no período de safra e entressafra são genotóxicos e citotóxicos. Políticas públicas deveriam ser discutidas para se buscar alternativas que diminuam a emissão desse poluente. / Abstract: Ethanol obtained from sugar cane has been considered an alternative fuel. However, in developing countries, the handly harvesting is usually done after to sugar cane burning which is responsible for seasonal emission of air pollutants. The genotoxicity of sugar cane burning residues (SCBRs) and particle surrogates of residual oil fly ash (ROFA) were observed in micronuclei (MN) assay in mouse peripheral blood and bone marrow cells as well as in the pollen mother cells of Tradescantia pallida (TRAC-MCN). The study also verified cytotoxicity and genotoxicity of cells treated with polycyclic aromatic hydrocarbons (PAHs) and suspension, in harvesting and non-harvesting particulated biomass. Higher frequency of MN was observed in harvesting TSP than non-harvesting and the cell death was higher in cells treated with PHAs in both particulates. Bcl-2 overexpression of p53 phosphorylated low expression was verified in the cells treated with PHAs in harvesting and non-harvesting in 24 and 48 hours after treatment. We can conclude that PHAs presenting in harvesting time, which represents burning sugar cane biomass and non-harvesting time (fuel fossil combustion) are cytotoxic and genotoxic. Public politics should be discussed to found alternatives which could decrease air pollution emissions. / Doutor
33

Effects of copper and nickel on subarctic Scots pine needles

Kukkola, E. (Eija) 07 September 1999 (has links)
Abstract Three different studies were conducted to elucidate the effects of copper (Cu) and nickel (Ni) on Scots pine needles. One was the Monchegorsk smelter emission gradient study on the Kola Peninsula, Russia, the second was the 3-year seedling and 6-year adult tree low-level CuNi and acid rain (H2SO4 at pH 3) irrigation study at Kevo, Finland. In the third study seedlings were exposed to Cu and Ni for a one season in Oulu, Finland. Ni accumulated efficiently in needles, and this accumulation was seen in each of the different studies. The Cu concentrations remained low in needles, except near the Monchegorsk smelters. The addition of Ni together with Cu in Oulu seemed to enhance the accumulation of Ni into the needles of Scots pine seedlings. Plasmolysis may be related to both drought and the Ni treatment, as observed in Oulu, because plasmolysis was statistically more abundant in the 15 mg Ni kg-1 dry soil treated needles than in other treatments except in 25 mg Ni kg-1 dry soil. Cu induced lipid peroxidation of chloroplast membranes was visible under transmission electron microscope (TEM) as light colored, swollen thylakoids in chloroplasts near the Monchegorsk smeltersand also in needles exposed to 25 Ni+50 Cu mg kg-1 in soil in Oulu. Some year to year variation in the frost hardening process was seen in metal and acid treated needles, which may have caused the maximum frost hardiness level drop after CuNi, pH3 and CuNi/pH3 treatments. Root growth was increased by 5 mg Ni kg-1 dry soil in soil in Oulu, but 15 mg Ni kg-1 dry soil Ni in soil decreased root growth and increased root tip dieback. 25 Ni+50 Cu mg kg-1 dry soil in soil markedly decreased root growth. The proportion of oxidized glutathione in Cu-treated needles was smaller than in Ni-treated needles, but roots had higher peroxidase activity levels. However, Ni seemed to cause more oxidative stress to seedlings than copper.
34

Development of a laser induced fluorescence technique for the analysis of organic air pollutants

Forbes, Patricia B.C. 04 June 2010 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants which are of concern due to their potential human toxicity. They are formed during numerous combustion processes, including biomass burning and diesel vehicular emissions, which are of relevance in developing countries. A novel analytical screening method for atmospheric polycyclic aromatic hydrocarbons (PAHs) was developed in this study based on laser induced fluorescence (LIF) of samples on quartz multi-channel polydimethylsiloxane (PDMS) traps. A tunable dye laser with a frequency doubling crystal provided the excitation radiation, and a double monochromator with a photomultiplier tube detected emitted fluorescence. The method allowed for the rapid (<5 min), cost effective analysis of samples. Those yielding interesting results could be further analysed by direct thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS, with limits of detection of ~0.3 ng.m-3), as photodegradation was minimal (<10% over 5 min irradiation). Without any signal optimization, a LIF detection limit of ~1 ìg.m-3 was established for naphthalene using a diffusion tube (diffusion rate of 2 ng.s-1) and 292 nm excitation. Gas standards which facilitated the uniform distribution of analyte across each of the 22 PDMS tubes were provided by easily constructed diffusion tubes for naphthalene and by a gas chromatographic fraction collection method for the less volatile target PAHs. The methods developed were successfully tested in a number of applications which are of relevance to southern Africa, as emissions from sugar cane burning, household fires, diesel vehicles and industries were monitored. The LIF method allowed for the differentiation between impacted and non-impacted industrial sites, and the importance of naphthalene as an indicator for atmospheric PAHs was verified in that this PAH was the most abundant in the various applications which were investigated. The multi-channel silicone rubber traps were also evaluated theoretically and practically in the denuder configuration, in order to monitor PAHs in both the gas and particle phases, which is important in terms of human health effects. The novel LIF method developed in this study has the potential to serve as a screening tool to avoid the comprehensive and costly analysis of samples which do not contain appreciable levels of PAHs. The experimental procedure is simple and rapid, with acceptably low limits of detection, even with the initial, unoptimized optical arrangement and without extensive time-averaging. LIF also provides selectivity without the need for sample clean-up and separation processes. The LIF method could be further optimized by improving the laser energy stability, as well as by the investigation of possible time resolution techniques. As equipment cost considerations were important, it is possible that the LIF screening method could find application in a centralized environmental laboratory for the southern African region. This would facilitate the widespread monitoring of atmospheric PAHs in a cost effective manner. / Thesis (PhD)--University of Pretoria, 2010. / Chemistry / unrestricted
35

Exposure to birch pollen and development of atopic disease in childhood /

Kihlström, Anne, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
36

Μελέτη των ατμοσφαιρικών ρύπων στην πόλη της Πάτρας με τη μέθοδο της ανάλυσης σε κύριες συνιστώσες

Σούφλα, Ευαγγελία 04 September 2013 (has links)
Μελέτη των ατμοσφαιρικών ρύπων στην πόλη της Πάτρας για το έτος 2010 με τη μέθοδο της ανάλυσης σε κύριες συνιστώσες και κάνοντας χρήση του στατιστικού πακέτου Minitab16 / Research on air pollutants in the city of Patras for the year 2010 using the method of Principal Components Analysis. The results are elaborated using the statistical program minitab16.
37

Efeitos da poluição atmosférica em marcadores inflamatórios pulmonares e sistêmicos de indivíduos submetidos ao exercício físico em ambiente aberto e fechado /

Coripio, Iris Cristina January 2019 (has links)
Orientador: Dionei Ramos / Resumo: Introdução: A poluição atmosférica é um assunto discutido mundialmente, causando um impacto na saúde humana e se tornando um grave problema de saúde pública, condições meteorológicas como temperatura, e umidade relativa do ar, também podem influenciar na magnitude dos efeitos adversos da poluição atmosférica na saúde humana.Objetivo:Verificar impactos da exposição aos poluentes atmosféricos sobre internações hospitalares por doenças cardiovasculares em uma população adulta, e o efeito da realização de exercício aeróbico em ambiente aberto e fechado com diferentes concentrações de MP2,5, temperatura e umidade relativa do ar na toxicidade pulmonar de indivíduos sedentários e ativos.Métodos: Registros de internações hospitalares por doenças cardiovasculares captados a partir da base de dados referentes ao sistema único de saúde no período de janeiro de 2014 a dezembro de 2015. Níveis de MP10, NO2, temperatura e umidade relativa foram registrados. No segundo estudo foram avaliados 27 indivíduos, divididos em dois grupos: ativos e sedentários submetidos a um exercício aeróbico em ambiente aberto e fechado. Níveis séricos de CC16, monóxido de carbono no ar exalado (COex), e parâmetros hemodinâmicos foram coletados antes e após a prática da atividade, concentrações de MP2,5, temperatura e umidade relativa do ar foram mensurados durante todo exercício. O nível de significância foi considerado p<0,05. Conclusões: Foi concluído que o impacto da exposição aos poluentes atmosféricos, pri... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: Air pollution is a subject discussed world wide, inducing an impact on human health and becoming a severe public health problem, weather conditions such as temperature and relative humidity can also influence the magnitude of the adverse effects of air pollution on human health. Objective: To verify the impact of exposure to air pollutants on hospital admissions due to cardiovascular diseases in an adult population and the effect of aerobic exercise in outdoor and indoor ambient with different concentrations of PM2.5, temperature and relative air humidity in pulmonary toxicity of sedentary and active individuals. Methods: Records of hospital admissions for cardiovascular diseases collected from Brazilian Unified Health System (SUS) database from January 2014 to December 2015. Levels of PM10, NO2, temperature and relative humidity were recorded. In the second study, 27 subjects were evaluated, splited into two groups: active and sedentary subjects submitted to an aerobic exercise in an outdoor and indoor ambient. Serum levels of CC16, carbon monoxide in the exhaled air (COex), and hemodynamic parameters were collected before and after the practice of the activity, concentrations of PM2.5, temperature and relative humidity were measured throughout the exercise. The significance level was considered p<0.05. Conclusions: It was concluded that the impact of exposure to air pollutants mainly PM10 on hospital admissions for cardiovascular diseases in adults, and PM2.5 ... (Complete abstract click electronic access below) / Mestre
38

Análise da fonte e composição da poluição atmosférica em diferentes locais da região metropolitana de São Paulo / Analysis of source and composition of air pollution in different locations in the Metropolitan Region of São Paulo

Ramires, Letícia Ogushi Romeiro 10 January 2013 (has links)
Grandes cidades, como São Paulo, são afetadas de forma significante pela poluição atmosférica. É de grande importância a caracterização das fontes emissoras da poluição atmosférica, não somente nas regiões centrais, mas também nas regiões periféricas, pois a composição da poluição pode não ser homogênea em toda a extensão da cidade. Neste estudo foram caracterizados os componentes da poluição atmosférica em quatro regiões dentro cidade de São Paulo. Para este fim foram Coletados Material Particulado (PM2.5) durante vinte dias no período de inverno de 2011 e vinte dias durante o período de verão de 2011. O material foi coletado através de filtros de policarbonato com 24 h de exposição, e foi submetido a análises gravimétricas, determinação da concentração de Black Carbon por refletância e determinação da composição elementar por Fluorescência de Raios-X. A identificação das diferentes fontes geradoras de material particulado foi baseada na análise de Componentes Principais (ACP). A variação da concentração da massa do material particulado fino (PM2.5) em g/m3 não teve diferença significativa entre os locais amostrados, mas mostrou diferença entre as estações do ano, sendo maior no período do inverno em todos os locais. A proporção do Black Carbon teve um comportamento diferente da massa. O Black Carbon não variou significantemente entre as estações do ano, porém apresentou diferença entre os locais amostrados, destacando-se no Parque do Ibirapuera e na Zona Leste. Foram encontrados 3 Fatores que explicam 75% da variabilidade. O Fator 1 é constituído pelos elementos Ti, V, Mn, Fe, Ni, Pb, P, S Cr e K e foi atribuído como sendo associado à ressuspensão de solo e emissões veiculares, O Fator 2 é composto por V, P, BC, e S e foi interpretado como sendo representativo de emissões veiculares de combustíveis com alto teor de enxofre. O Fator 3 é 7 associado aos elementos BC e Ni e foi interpretado como sendo produzido por emissões veiculares em geral / Large cities such as São Paulo are significantly affected by air pollution. It is of great importance to characterize the emission sources of air pollution, not only in the central regions of the city of São Paulo, but also in peripheral regions, do to the fact that the composition of pollution may not be homogeneous across the city area. This study shows the Characterized the components of air pollution in four different areas of the metropolitan region of São Paulo. Particulate matter (PM 2.5) was collected during the winter of 2011 and summer of 2011. It was collected 24-h PM2.5 samples, employing gravimetry to determine PM2.5 mass concentrations; reflectance to quantify black carbon concentrations and X-ray fluorescence to characterize elemental composition. A receiver model based on principal component analysis (PCA) was used to identify the involvement of the different sources for the generation of particulate matter. The fine particulate matter (PM2.5) in g/m3 did not differ significantly among the locations. However, the results collected showed differences according the seasons evaluation, being higher in the winter for all regions sampled. The proportion of Black Carbon behaves differently than the mass. It does not vary significantly between the seasons, but between the different regions. The proportion of Black Carbon was higher in Ibirapuera Park and the East Zone. Was found 3 factors explaining 75% of the variability. Factor 1 consists of the elements Ti, V, Mn, Fe, Ni, Pb, P, S Cr e K and was related to crustal emission (soil) and vehicle emissions, Factors 2 consists of the elements V, P, BC, e S and can be related to vehicular emissions of fuels with high sulfur content. Factor 3 consists of the elements BC and Ni was associated to vehicle emission
39

Estudo da influência do material particulado na incidência e mortalidade por câncer na cidade de São Paulo / The influence of particulate matter on the incidence and mortality cancer in São Paulo

Yanagi, Yoshio 19 October 2010 (has links)
Objetivo. Este trabalho teve como objetivo geral verificar a influência do poluente atmosférico material particulado inalável (MP10) na incidência e na mortalidade por câncer, na cidade de São Paulo. Métodos. Os dados de câncer foram coletados do Registro de Câncer de São Paulo e os dados do poluente provenientes da CETESB. Foram utilizadas técnicas estatísticas para verificar a relação do MP10 sobre a incidência e a mortalidade por câncer (pele, pulmão, laringe, tireóide, estômago, próstata, colo do útero, mama, bexiga, cólon, esôfago e reto), nos distritos do Brás, Santana, Moóca, Cambuci, Moema, Freguesia do Ó, Campo Belo, Lapa, Consolação, Santo Amaro e São Miguel. Os distritos também foram agrupados, de acordo com as concentrações de MP10, para orientar a expansão da rede de monitoramento do poluente na cidade de São Paulo. Resultados. Os resultados mostraram que, para alguns tipos de câncer (pele, pulmão, tireóide, laringe e bexiga), os coeficientes de correlação estatística ficaram entre 0,60 e 0,80, em alguns períodos, para a incidência. Para a mortalidade, o câncer de pulmão apresentou mais correlações neste intervalo. O agrupamento dos distritos permitiu a formação de quatro grupos distintos, o que possibilitaria, após estudo técnico, a redistribuição de alguma estação de monitoramento do segundo grupo para outras regiões da cidade, como leste ou sul. A Análise Espacial mostrou que distritos distantes do centro da cidade apresentaram risco relativo (RR) acima do esperado, dependendo do tipo de câncer. Conclusões. O estudo mostrou que o poluente atmosférico MP10 tem correlação alta com a incidência de alguns tipos de câncer (pele, pulmão, tireóide, laringe e bexiga) e com a mortalidade por câncer de pulmão, em alguns períodos, na cidade de São Paulo. A expansão da rede de monitoramento de MP10, na cidade de São Paulo, poderia ser direcionada às regiões leste ou sul / Objective. The general objective of this study was to verify the influence of pollutant inhalable particulate matter (PM10) on the incidence and cancer mortality in the city of São Paulo. Methods. The cancer data were collected from the Cancer Registry of São Paulo and pollutant data from the CETESB. Statistical techniques were used to investigate the relationship between PM10 and the incidence and mortality of cancer (skin, lung, larynx, thyroid, stomach, prostate, cervix, breast, bladder, colon, esophagus and rectum), in the districts of Brás, Santana, Moóca, Cambuci, Moema, Freguesia do Ó, Campo Belo, Lapa, Consolação, Santo Amaro and São Miguel. The districts were also grouped according to the concentrations of PM10, to guide the expansion of the pollutant monitoring network in São Paulo. Results. The results showed that for some types of cancer (skin, lung, thyroid, larynx and bladder), the statistical correlation coefficients were between 0.60 and 0.80, in some periods, for incidence. For mortality, lung cancer showed more correlations in this interval. The grouping of districts allowed the formation of four distinct groups, which would allow, after a technical study, the redistribution of any monitoring station in the second group to other parts of the city, like east or south. A Spatial Analysis showed that districts distant from the center presented a relative risk (RR) greater than expected, depending on the type of cancer. Conclusions. The study showed that air pollutant PM10 has high correlation with the incidence of some cancers (skin, lung, thyroid, larynx and bladder) and mortality from lung cancer in some periods, in São Paulo. The expansion of network monitoring PM10, in the city of São Paulo, could be targeted to areas east or south
40

Avaliação de mutagenicidade, citotoxicidade e expressão de proteínas relacionadas a apoptose, Bak, BCL-2 e P53 fosforilado, em células tratadas com fuligem e particulado total de queima de cana-de-açúcar

Peron, Mariana Cristina Caloni [UNESP] 18 December 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-12-18Bitstream added on 2014-06-13T18:41:08Z : No. of bitstreams: 1 peron_mcc_dr_arafcf.pdf: 971260 bytes, checksum: b130fbae5d9dc40c7aae26eafe9d69b4 (MD5) / O etanol obtido da cana-de-açúcar tem sido considerado um combustível alternativo. Entretanto, em países em desenvolvimento, a colheita de cana é realizada manualmente depois da queima, sendo responsável pela emissão sazonal de poluentes atmosféricos. A mutagenicidade dos resíduos de queima de cana (RQCA) e as partículas presentes na ROFA (residual oil fly ash) foram observados nos ensaios de micronúcleo em células sanguíneas de camundongos e de células mãe de grão de pólen de Tradescantia pallida (TRAC-MCN) particulado. O estudo também verificou a citotoxicidade, apoptose e genotoxicidade nas células tratadas com extrato orgânico contendo grande quantidade de HPAs e suspensão na biomassa do período de safra e entressafra. Uma alta freqüência de MN foi observada no TSP do período de safra que na entressafra e a porcentagem de células mortas foi maior em células tratadas com extrato orgânico contendo grande quantidade de HPAs e particulado. Elevada expressão de Bcl-2 e baixa expressão de p53 fosforilado foi verificado em células tratadas com extrato orgânico contendo grande quantidade de HPAs no período de safra e entressafra e em 24 e 48h pós-tratamento. É possível concluir que os HPAs presentes no período de safra e entressafra são genotóxicos e citotóxicos. Políticas públicas deveriam ser discutidas para se buscar alternativas que diminuam a emissão desse poluente. / Ethanol obtained from sugar cane has been considered an alternative fuel. However, in developing countries, the handly harvesting is usually done after to sugar cane burning which is responsible for seasonal emission of air pollutants. The genotoxicity of sugar cane burning residues (SCBRs) and particle surrogates of residual oil fly ash (ROFA) were observed in micronuclei (MN) assay in mouse peripheral blood and bone marrow cells as well as in the pollen mother cells of Tradescantia pallida (TRAC-MCN). The study also verified cytotoxicity and genotoxicity of cells treated with polycyclic aromatic hydrocarbons (PAHs) and suspension, in harvesting and non-harvesting particulated biomass. Higher frequency of MN was observed in harvesting TSP than non-harvesting and the cell death was higher in cells treated with PHAs in both particulates. Bcl-2 overexpression of p53 phosphorylated low expression was verified in the cells treated with PHAs in harvesting and non-harvesting in 24 and 48 hours after treatment. We can conclude that PHAs presenting in harvesting time, which represents burning sugar cane biomass and non-harvesting time (fuel fossil combustion) are cytotoxic and genotoxic. Public politics should be discussed to found alternatives which could decrease air pollution emissions.

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