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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.
741

Determinação de íons solúveis em água no material particulado MP10 coletado na Cidade Universitária - São Paulo, 2003 / Water Soluble Ions in the Particulate Matter PM10 collected at Cidade Universitária, São Paulo city, 2003

Avila, Simone Garcia de 25 February 2011 (has links)
As partículas atmosféricas com diâmetro aerodinâmico menor que 10 µm são classificadas por MP10. Essas partículas podem ser subdivididas em partículas grossas (entre 2,5 e 10 &#181;m) e finas (< 2,5 &#181;m), sendo que as últimas apresentam poder de penetração maior no organismo, podendo atingir os alvéolos pulmonares. O objetivo deste trabalho foi estudar espécies solúveis em água no material particulado MP10, coletado na Cidade Universitária (São Paulo-SP) durante o ano de 2003, como também, investigar a variação sazonal destas espécies na atmosfera de São Paulo, caracterizando as principais fontes de emissões existentes no sítio de estudo, tais como possíveis formações de espécies secundárias e influências de transporte de massas de ar. As amostras foram coletadas no Instituto de Astronomia, Geofísica e Ciências Atmosféricas da USP, utilizando filtros de fibra de quartzo e um amostrador de grande volume. A amostragem ocorreu a cada quinze dias, entre os meses de abril/2003 e maio/2004 (n=28), sendo realizadas também duas amostragens durante dias consecutivos, uma ocorrendo em março/2003 (n=5) e outra em julho/2003 (n=10). Esses dois períodos correspondem a estudos de casos, no qual o primeiro é caracterizado pela ocorrência de precipitação nos dias amostrados, enquanto, o segundo representa dias de ausência de precipitação, característicos do inverno na região de estudo. O tempo de amostragem foi de 24 horas. A extração da fração solúveis em água foi feita por via aquosa e a quantificação por cromatografia de íons. O inverno/2003 representou a estação de maior concentração média de MP10 e também das espécies estudadas, entretanto, considerando o intervalo de concentração obtido em cada estação, no outono/2003 foram encontrados valores de MP10 tão elevados quanto no inverno/2003. Nenhuma amostra apresentou concentração de material particulado acima do limite recomendado pela legislação brasileira (150 µg m-3), porém, considerando o limite de MP10 recomendado pela Organização Mundial de Saúde (50 µg m-3), apenas a primavera/2003 e o verão 2003/2004 não apresentaram amostras acima deste limite. O sulfato representou a espécie mais abundante da fração solúvel em água do MP10, não apresentando grandes variações ao longo das estações do ano. A razão entre os ácidos fórmico e acético mostrou que as reações fotoquímicas contribuem mais intensamente para a presença destas espécies na atmosfera do sítio estudado. O estudo das trajetórias de massas de ar e também as correlações entre as espécies mostraram que o sítio de estudo recebe influência de aerossóis marinhos e também de locais provenientes de queima de biomassa. / PM10 is classified by the atmospheric particulate matter that present the diameter smaller than 10 µm. These particles may be divided in the coarse fraction (diameter between 2,5 and 10 µm) and fine fraction (<2,5 µm). The fine fraction presents high power penetration in the human organism. The objective of this study was to determinate the water-soluble ions in the PM10 collected in the Cidade Universitária (São Paulo, SP) during 2003 year and to investigate the seasonal variation of these species, characterizing the principal emissions sources in the studied site, secondary reaction and air mass transport. Samples were collected in the Instituto de Astronomia, Geofísica e Ciências Atmosféricas of USP, using the high volume sample and fiber quartz filter. The sampling occurred every 15 days, between April/2003 and May/2004 (n=28). It was done two sampling in consecutive days, during March/2003 (n=5) and July (n=10). The first period was characterizing by occurrence of precipitation during the sample days and the second period was characterizing by absence of precipitation. The sample time was 24 hours. The extraction of the water soluble ions was done using water and the quantification by ions chromatography. The winter/2003 presented the highest average concentration of PM10 and of the studied species. However, considering the range of the concentration, the autumn/2003 presented PM10 concentration as high as winter/2003. It was not noticed concentrations of PM10 above that established by Brazilian laws (150 µg m-3), but considering the limit of PM10 established by World Health Organization (50 µg m-3), only spring/2003 and summer 2003/2004 did not present concentration highest than this limit. Sulfate was the more abundant studied species. The concentration of that ion did not present variation each season of the year. The ratio between formic acid and acetic acid showed that the photochemical reaction is the principal responsible for the presence of these acids in the atmosphere of studied site. The study of back mass trajectories and the correlation between same species showed that the São Paulo receive influence of marine aerosol by air mass transported and aerosols by region of the biomass burning, too.
742

Application of zeolite and titanium dioxide in the treatment of environmental contaminants.

January 1999 (has links)
by Hei Yuk Kwan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 81-87). / Abstract also in Chinese. / ABSTRACT --- p.i / DECLARATION --- p.ii / ACKNOWLEDGEMENT --- p.iii / TABLE OF CONTENTS --- p.iv / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.vii / Chapter CHAPTER ONE : --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.1.1. --- Volatile Organic Compounds --- p.1 / Chapter 1.1.2. --- Photocatalytic Oxidation --- p.2 / Chapter 1.1.3. --- Adsorption --- p.4 / Chapter 1.2. --- Scope of Work --- p.8 / Chapter CHAPTER TWO : --- PHOTOCATALYSIS --- p.10 / Chapter 2.1 --- Fundamental --- p.10 / Chapter 2.2. --- Experimental --- p.14 / Chapter 2.2.1. --- Materials --- p.14 / Chapter 2.2.2. --- Instruments --- p.14 / Chapter 2.2.3. --- Experimental Conditions --- p.19 / Chapter 2.2.4. --- Procedure --- p.20 / Chapter 2.3. --- Results and Discussion --- p.28 / Chapter 2.3.1. --- Photocatalytic Degradation of DCE --- p.28 / Chapter 2.3.2. --- Photocatalytic Degradation of TCE --- p.31 / Chapter 2.3.3. --- Photocatalytic Degradation of DCE and TCE Binary System --- p.34 / Chapter 2.3.4. --- Photocatalytic Degradation of Ethyl Acetate --- p.39 / Chapter 2.3.5. --- Photocatalytic Degradation of Methyl Isopropyl Ketone --- p.41 / Chapter 2.3.6. --- Photocatalytic Degradation of Ethyl Acetate and Methyl Isopropyl Ketone Binary System --- p.43 / Chapter CHAPTER THREE : --- ADSORPTION --- p.47 / Chapter 3.1. --- Fundamental --- p.47 / Chapter 3.1.1. --- Mordenite --- p.51 / Chapter 3.1.2. --- Activated Carbon --- p.55 / Chapter 3.2. --- Experimental --- p.58 / Chapter 3.2.1. --- Materials --- p.58 / Chapter 3.2.2. --- Instrument --- p.59 / Chapter 3.2.3. --- Procedure --- p.60 / Chapter 3.3. --- Results and Discussion --- p.65 / Chapter 3.4. --- "Adsorption Isotherm of 1,3,5-trimethylbenzene on Mordenite in Aqueous Phase" --- p.70 / Chapter 3.5. --- "Thermal Regeneration of 1,3,5-trimethylbenzene on Mordenite in Aqueous Phase" --- p.72 / Chapter CHAPTER FOUR : --- CONCLUSION --- p.79 / REFERENCES --- p.81
743

On the regression model with count data: with application in air pollution data.

January 1999 (has links)
by Kwok-Fai Mo. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 74-79). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Statistical Modeling --- p.5 / Chapter 2.1 --- Poisson Regression --- p.5 / Chapter 2.2 --- Overdispersion and Autorrelation --- p.7 / Chapter 2.3 --- Generalized Estimating Equation --- p.9 / Chapter 2.4 --- Zeger's Mehthod --- p.12 / Chapter 2.5 --- Multicollinearity --- p.18 / Chapter 2.5.1 --- The Modified Generalized Estimating Equation --- p.18 / Chapter 2.6 --- Bootstrapping Method --- p.21 / Chapter 2.7 --- The Bootstrap Choice of Ridge Parameter --- p.23 / Chapter 3 --- The Robustness of Zeger's Approach to the Specification of ηt - Simulation Study --- p.26 / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.2 --- Zeger's Algorithm with Varoious Time Series Data --- p.27 / Chapter 3.2.1 --- Data without Multicollinearity --- p.27 / Chapter 3.2.1 --- Data with Multicollinearity --- p.34 / Chapter 3.3 --- Modified Generalized Estimating Equation Approach --- p.40 / Chapter 3.3 --- The Choice of Ridge Paramter in Bootstrap --- p.42 / Chapter 4 --- Real Example --- p.46 / Chapter 4.1 --- Data Structure --- p.46 / Chapter 4.2 --- Model Building --- p.49 / Chapter 4.3 --- Single Pollutant Model --- p.57 / Chapter 4.4 --- Multiple Pollutant Model --- p.62 / Chapter 5 --- Conclusion and Discussion --- p.64 / Appendix --- p.69 / References --- p.74
744

Economie géographique et croissance : le cas des émissions polluantes industrielles / Economic geography and growth : the case of polluting industrial emissions

Leturque, Emmanuelle 20 June 2018 (has links)
La thèse s’intéresse au rôle des pollutions industrielles sur les mécanismes de l’agglomération et de la croissance. Elle s’inscrit dans le corpus d’Economie Géographique et propose à la fois un travail de modélisation et une étude empirique. La localisation des activités industrielles polluantes représente un enjeu majeur pour les régions. Le gouvernement souhaite maintenir des activités économiques et une forte attractivité, tout en limitant les effets néfastes des dégradations environnementales issues des industries polluantes. En même temps, les pollutions industrielles affectent les autres secteurs et les ménages. Nous avons, tout d'abord, discuté les enjeux théoriques de la littérature concernant l’impact de l’agglomération sur la croissance et sur les émissions industrielles polluantes. Cela permet de mettre en évidence des limites des travaux de Nouvelle Economie Géographique et Croissance endogène (NEGG) sur la question, telle que la faible considération des dommages environnementaux. Ensuite, nous avons introduit une régulation environnementale dans un modèle de NEGG. Lorsque la taxe est différenciée entre les régions, elle a tendance à rendre l’équilibre de localisation plus dispersé. Enfin, nous montrons dans une étude empirique que les firmes des secteurs polluants bénéficient moins des économies d’agglomération. / The thesis focuses on the role of industrial emissions on economic mechanisms linking agglomeration and growth. This PhD thesis is settled in Economic Geography literature and display both theoretical and empirical studies. Location of polluting activities, mainly industrial ones, represents a sensitive issue for local governments. They want to maintain economic dynamism while preserving regional environmental capital. One needs to better understand the role of environmental issues in the arbitrage between growth and spatial equity. Indeed, industrial agglomeration impacts others sectors and household welfare through air pollution. Our review of literature shows that the effects of agglomeration on growth are well established. However, studies considering industrial pollution as a dispersion force are rare. We first build a model of NEGG with pollution regulation toward industrial firms. Then, an empirical study is conducted where we show that industrial firms benefit less from agglomeration economies.
745

Análise de risco à saúde diante da exposição a poluentes liberados durante o processo de cocção de alimentos

Uemura, Michele Leiko 09 September 2013 (has links)
Submitted by Rosina Valeria Lanzellotti Mattiussi Teixeira (rosina.teixeira@unisantos.br) on 2015-04-30T14:53:46Z No. of bitstreams: 1 Michele L. Uemura.pdf: 1173721 bytes, checksum: 7e9cfc9c787bea066f741638c8b76777 (MD5) / Made available in DSpace on 2015-04-30T14:53:46Z (GMT). No. of bitstreams: 1 Michele L. Uemura.pdf: 1173721 bytes, checksum: 7e9cfc9c787bea066f741638c8b76777 (MD5) Previous issue date: 2013-09-09 / Introduction: According to the Household Budget Survey (HBS) from 2008 to 2009, the percentage of expenditure on food outside the home among the population residing in urban areas was 33.1%. The activity held in commercial kitchens is characterized as a process that uses intensively its workforce, for prolonged periods and in inadequate conditions. The assessment of the levels of pollutants in the Buffet restaurants both in the kitchen and in the hall is relevant for surveying the risk to vulnerable individuals. Methods: Cross-sectional study was done, from May to July 2012, which ten commercial Buffet type restaurants were analyzed, evaluating the air pollutant concentrations within the kitchen and salon service in the city of Santos. Five kitchen staff and five ballroom, totaling 100, were selected in 10 restaurants. The European Community Respiratory Health Survey (ECRHS) for adults was used to collect morbidity data. The data collection of particulate matter 2.5 ¿m was performed in duplicate, in the kitchens and lounge during food preparation. NO2 passive samplers were placed inside the kitchen and service room thirteen consecutive days in triplicate. Descriptive analyzes were performed for all variables. Quantitative variables were calculated by measures of central tendency and dispersion. Qualitative variables were described in terms of their absolute and relative numbers. The differences between the averages of the pollutants in the kitchen and salon service were done through the testing u t test, Mann-Whitney test. The differences in the concentrations of pollutants in the kitchen and salon service were done through analysis of variance for independent samples (ANOVA). In situations where there was a difference between the measurements was applied Tukey-HSD test to identify these differences. Results: The levels of PM2, 5 issued during cooking of food were 60-459 g/m3 for kitchens and 5-80 ¿g/m3 in the halls, and NO2 between 60 and 180 ¿g/m3 in kitchens and 40 and 60 ¿g/m3 in the halls, the differences being statistically significant. The prevalence of respiratory symptoms suggestive of asthma in total workers surveyed was 20%. But there was no association between the occurrence of respiratory morbidity and perform such labor activities in the kitchen. Conclusion: This study shows the high exposure to air pollutants emitted in kitchens, increasing the risk of harm to respiratory health of these workers. / Introdução: Segundo a Pesquisa de Orçamento Familiar de 2008-2009, o percentual de despesas com alimentação fora do domicílio entre a população residente em áreas caracterizada como um processo que utiliza intensivamente sua mão de obra, por períodos prolongados e em condições inadequadas. A avaliação dos níveis de poluentes nos restaurantes tipo Buffet tanto na cozinha quanto no salão é relevante para o levantamento do risco para indivíduos vulneráveis. Metodologia: Estudo transversal, de maio a julho de 2012, em dez restaurantes comerciais tipo Buffet, avaliando as concentrações de poluentes atmosféricos no interior da cozinha e no serviço de salão, na cidade de Santos. Cinco funcionários da cozinha e cinco do salão, totalizando 100 foram selecionados em 10 restaurantes. O European Community Respiratory Health Survey (ECRHS) foi utilizado para a coleta de dados de morbidade. A coleta do material particulado 2,5 µm foi realizada em duplicata, no interior das cozinhas e no salão durante o preparo dos alimentos. Amostradores passivos de NO2 foram instalados no interior das cozinhas e no serviço de salão por treze dias consecutivos sendo a coleta realizada em triplicata. Foram feitas análises descritivas de todas as variáveis. Para as variáveis quantitativas foram calculadas medidas de tendência central e de dispersão. As variáveis qualitativas foram descritas em termos dos seus números absolutos e relativos. As diferenças entre as médias dos poluentes, na cozinha e no serviço de salão através do teste t e teste u de Mann-Whitney. As diferenças nas concentrações dos poluentes na cozinha e no serviço de salão através da análise de variância para amostras independentes (ANOVA). Nas situações em que havia diferença entre as medidas foi aplicado o teste HSD- Tukey para identificar essas diferenças. Resultados: Os níveis de PM2,5 emitidos durante a cocção dos alimentos foram de 60 a 459 ¿g/m3 para as cozinhas e de 5 a 80 ¿g/m3 nos salões e para NO2 entre 60 e 180 ¿g/m3 nas cozinhas e 40 e 60 ¿g/m3 nos salões, sendo as diferenças estatisticamente significativas. A prevalência de sintomas respiratórios sugestivos de asma no total dos trabalhadores investigados foi de 20%. Porém não foi observada associação entre a ocorrência de morbidade respiratória referida e exercer as atividades laborais na cozinha. Conclusão: Foi evidenciada a alta exposição aos poluentes atmosféricos emitidos em cozinhas aumentando o risco de agravos à saúde respiratória destes trabalhadores.
746

"Relação da poluição atmosférica com a citologia nasal em pacientes com rinite alérgica, residentes na cidade de São Paulo, nas diferentes estações do ano" / Relationship between environmental pollution and nasal cytology in patients with allergic rhinitis, living in São Paulo city, during the different seasons of the year

Fabiana Maia Nobre Rocha 18 November 2005 (has links)
Diferentes estudos têm demonstrado uma maior prevalência de rinite alérgica nas áreas urbanas, sugerindo um efeito decorrente da exposição à poluentes. Por esta razão, resolvemos estudar a relação da poluição atmosférica com os achados do citológico nasal em 11 pacientes com rinite alérgica nas quatro estações do ano e compará-los a 12 indivíduos normais. No verão, observamos um aumento significante de eosinófilos no grupo alérgico (p = 0,007) e um predomínio de células ciliadas no grupo controle (p = 0,021). No outono, houve um predomínio de neutrófilos no grupo controle (p = 0,027). No inverno, ocorreu um aumento de neutrófilos (p = 0,015) no grupo controle. Houve um aumento das células caliciformes (p = 0,019) no grupo alérgico. Na primavera, ocorreu um aumento dos neutrófilos (p = 0,025) no grupo controle / Different studies have demonstrated an increase in the prevalence of allergic rhinitis in urban areas, suggesting an effect resulting from exposure to pollutants. Therefore, we studied the relationship between atmospheric pollution and nasal cytological findings in 11 patients with allergic rhinitis during the four seasons of the year compared to 12 normal individuals. In summer, a significant increase in eosinophils was observed in the allergic group (p = 0.007) and there was a predominance of ciliated cells in the control group (p = 0.021). In autumn, neutrophils predominated in the control group (p = 0.027), and an increase in neutrophils (p = 0.015) was observed in winter. An increase in goblet cells (p = 0.019) was observed in the allergic group. In spring, there was an increase of neutrophils (p = 0.025) in the control group
747

Possível efeito da poluição ambiental atmosférica e o estresse oxidativo em pacientes com infarto agudo do miocárdio

Freitas, Fernando Araújo de January 2012 (has links)
Doenças desencadeadas ou agravadas pela contaminação ambiental resultante dos poluentes atmosféricos vêm se tornando cada vez mais preocupantes, entre as quais se destacam as doenças respiratórias e cardiovasculares. Vários estudos têm mostrado uma associação entre poluição atmosférica e o desenvolvimento de doenças cardiovasculares, especialmente devido ao material particulado no ar. Este material, por sua vez, possui diversas substâncias em sua composição química, dentre eles os hidrocarbonetos policíclicos aromáticos (HPAs), os quais têm sido fortemente associados com o processo inflamatório em estudos in vitro. O benzo[a]pireno (BaP) é um dos HPAs mais importantes, sendo que seu metabólito mais utilizado como biomarcador de exposição é o 1-hidroxipireno (1-HP) urinário. Considerando as doenças cardiovasculares, o infarto agudo do miocárdio (IAM) é um dos desfechos clínicos mais relevantes pela sua alta morbidade e mortalidade. Sabe-se que, além dos efeitos da poluição atmosférica, outros fatores são considerados determinantes no desenvolvimento de doenças cardiovasculares, como o tabagismo, sedentarismo, dislipidemias, histórico familiar, entre outros. Neste contexto, o presente trabalho avaliou a possível associação entre exposição ambiental ao benzo[a]pireno, inflamação e biomarcadores do estresse oxidativo em pacientes com IAM. Fizeram parte deste estudo indivíduos diagnosticados com IAM (N=58) e indivíduos não infartados controles (N=41), sendo cada grupo dividido em fumantes e não fumantes. A concentração urinária de 1-HP foi quantificada por CLAE e os resultados corrigidos pela excreção urinária de creatinina. Análises laboratoriais de rotina como exames hematológicos, bioquímicos, bem como biomarcadores inflamatórios (PCRus) foram quantificados, além de biomarcadores do estresse oxidativo (MDA, SOD, δ-ALA-D, CAT, GPx), antioxidantes não-enzimáticos exógenos (β-caroteno, licopeno, vitamina E e retinol) e carboxihemoglobina (COHb), todos em amostras sangüíneas. Os resultados demonstram aumentos significativos dos níveis de 1-HP urinário, PCRus, MDA e das atividades das enzimas CAT e GPx em pacientes pós-infarto (fumantes e não fumantes) e ainda uma inibição da δ-ALA-D somente no grupo pós-infarto não fumantes, comparados aos grupos controles. Além disso, uma diminuição na atividade enzimática de SOD e dos níveis de β-caroteno foram encontrados nos dois grupos pós-infarto comparados aos grupos controles. Os níveis de COHb não apresentaram alterações significativas nos grupos estudados, exceto para os fumantes, independente do infarto. Correlações positivas de MDA (r=0,326, p=0,01) e CAT (r=0,474, p=0,001) com os níveis urinários de 1-HP foram encontradas. Por outro lado, δ-ALA-D (r=-0,353, p=0,01) e β-caroteno (r=-0,309, p=0,05) foram negativamente correlacionados com a excreção urinária de 1-HP; as correlações foram obtidas somente para os grupos não-fumantes. Os resultados indicam que os indivíduos com IAM apresentam maiores níveis do biomarcador inflamatório PCRus, além de alterações em vários biomarcadores de dano oxidativo em conjunto com um aumento da excreção urinária de 1-HP. Desta forma, estes resultados sugerem que, para uma melhor compreensão da exposição ao benzo[a]pireno e eventos cardiovasculares, o tabagismo deve ser excluído. Ainda, os resultados demonstram que o BaP tende a aumentar a peroxidação lipídica, apesar de aumentar a atividade da catalase. Além disso, o BaP demonstrou inibir a enzima δ-ALA-D e atuar na depleção de β-caroteno. Desta forma, sugere-se que o BaP induz o estresse oxidativo e que este aumento, isoladamente e/ou em conjunto com o metabólitos ativos do benzo[a]pireno, podem contribuir para o desfecho clínico do infarto agudo do miocárdio em indivíduos não-fumantes. / Diseases caused or aggravated by environmental pollutants are becoming increasingly worrisome, especially respiratory and cardiovascular diseases. Several studies have shown an association between air pollution and the development of cardiovascular diseases, considering the existence of particulate matter in the air pollution. Particulate matter presents various substances in its chemical composition, e.g. polycyclic aromatic hydrocarbons (PAHs), which have been strongly associated with the inflammatory process in in vitro studies. Benzo[a]pyrene (BaP) is one of the most important PAHs, whose most commonly utilized biomarker of exposure is the urinary metabolite 1-hydroxypyrene (1-HP). Regarding cardiovascular diseases, acute myocardial infarction (AMI) is clinically relevant due to its high morbidity and mortality. In addition to air pollution effects, several other factors are determinant in the development of cardiovascular diseases, for instance, smoking, sedentary lifestyle, dyslipidemia, family history, etc. In this context, the present study evaluated the possible association of environmental exposure to BaP, inflammation and oxidative stress biomarkers in AMI patients. Patients diagnosed with AMI (N=58) and controls (N=41) were enrolled in this study and divided into smokers and non smokers. The urinary excretion of 1-hydroxypyrene (1-HP) was analyzed by HPLC and results were corrected by urinary creatinine values. Hematological and biochemical parameters, inflammatory (hsCRP) and oxidative stress (MDA, SOD, δ-ALA-D, CAT, GPx) biomarkers, exogenous non-enzymatic antioxidants (β-carotene, lycopene, vitamin E e retinol) and carboxyhemoglobin (COHb) were determined in blood samples. We report increases in 1-HP urinary excretion, hsCRP and MDA levels, in CAT and GPx enzymatic activities in post-infarction patients (smokers and non smokers) and also an inhibition of δ-ALA-D activity only in the post-infarction non smoker group, compared to the control groups (p<0.05). Furthermore, decreases in SOD enzymatic activity and β-carotene levels have been found in the post-infarction groups compared to controls. COHb levels did not change significantly in both groups, except for smokers which increased independently from the infarction. MDA (r=0.326, p=0.01) and CAT (r=0.474, p=0.001) were positively correlated with the levels of urinary 1-HP. On the other hand, δ-ALA-D (r=-0.353, p=0.01) and β-carotene (r=-0.309, p=0.05) were negatively correlated with 1-HP urinary excretion; correlations were obtained only with non smoker groups. Thus these results suggest that in order to better understand the exposure to BaP and cardiovascular events, smoking must be excluded. Moreover, BaP was shown to increase lipid peroxidation despite the increase in catalase activity; BaP was also able to inhibit δ-ALA-D enzymatic activity and deplete β-carotene levels. Therefore, our findings suggest that BaP increases oxidative stress by itself or in conjunction with its active metabolites, which may contribute to the clinical outcome of the AMI in non smokers.
748

Évolution de l’asthme au long cours : aspects méthodologiques et lien avec la pollution atmosphérique / Long-Term Trajectory of Asthma : Methodological Aspects and Impact of Outdoor Air Pollution

Sanchez, Margaux 16 June 2015 (has links)
Contrairement à la majorité des maladies chroniques qui s’aggravent progressivement, l’expression de l’asthme est variable au cours du temps. L’asthme peut apparaître, disparaître, s’aggraver ou s’améliorer au cours de plusieurs années, voire une décennie, à tout âge de la vie. Cette variabilité à long terme est particulièrement mal décrite chez l’adulte car les données sont rares. Par une approche épidémiologique, la thèse a pour objectif de mieux comprendre la variabilité de l’expression de l’asthme au long cours chez l’adulte dans deux cohortes françaises : E3N, l’Étude Épidémiologique auprès des femmes de la Mutuelle Générale de l’Éducation Nationale et EGEA, l’étude Épidémiologique des facteurs Génétiques et Environnementaux de l’Asthme. Le premier axe, méthodologique, porte sur la mesure de la variabilité de l’expression de l’asthme au long cours. Le second axe, environnemental, porte sur le rôle de la pollution atmosphérique sur cette variabilité. Concernant l’axe méthodologique, l’étude des réponses à une unique question sur l’asthme répétée 7 fois sur 13 ans dans le cadre de la cohorte E3N a montré qu’une succession incohérente de réponses (positives et négatives) reflétait une partie de la variabilité de l’activité de l’asthme à moyen terme, suggérant l’intérêt de cette approche pour affiner la caractérisation de l’expression de la maladie au cours du temps. Dans le contexte d’un intérêt croissant pour la santé perçue, l’étude d’une question portant sur l’auto-évaluation rétrospective du changement dans la santé respiratoire au cours des 10 dernières années a montré que l’information ainsi obtenue était complémentaire de celle d’outils épidémiologiques et cliniques existants pour décrire la trajectoire à long terme de l’asthme, et permettait de prédire en partie l’évolution de l’asthme.À la suite d’une récente méta-analyse regroupant 6 cohortes européennes (avec 23 000 participants) dont les résultats suggèrent le rôle d’une exposition chronique à la pollution atmosphérique dans l’incidence de l’asthme chez l’adulte, une analyse a porté sur l’évolution des traitements de fond et de secours de l’asthme sur une période de 4 ans en lien avec la pollution atmosphérique. Chez les femmes asthmatiques de la cohorte E3N, plus l’exposition chronique au dioxyde d’azote et aux particules était élevée, plus la consommation de corticoïdes inhalés augmentait au cours du temps, suggérant le rôle à long terme du dioxyde d’azote dans la progression de l’asthme. En conclusion, les résultats de la thèse montrent que des outils simples, tels que l’utilisation de réponses successives à une unique question sur l’asthme et l’auto-évaluation du changement dans la santé respiratoire sur 10 ans, peuvent être utilisés pour mieux caractériser la variabilité de l’expression de l’asthme au long cours, de façon complémentaire aux outils déjà existants. Associés à ceux de la littérature, les résultats de la thèse soutiennent le rôle délétère d’une exposition chronique à la pollution de l’air extérieur sur l’évolution de l’asthme au long cours et renforcent l’intérêt d’interventions de santé publique visant à diminuer la concentration des polluants atmosphériques. / Unlike most chronic diseases, which tend to get progressively worse over time, the expression of asthma is variable over time. Asthma may onset at any age and is known to clinically persist, possibly resolve, or present any combination of remissions and relapses over several years, even decades. Such long-term variability has been difficult to describe in adults as data are scarce. Through an epidemiological approach, the aim of the thesis is to gain a better understanding of the variability of asthma expression over the long term in adults, in two French cohorts: the E3N study (l’Étude Épidémiologique auprès des femmes de la Mutuelle Générale de l’Éducation Nationale) and the EGEA study (the Epidemiological study on the Genetics and Environment of Asthma). The first axis is methodological and relates to the characterization of asthma expression variability over the long term. The second axis is environmental and related to the effect of air pollution on such long-term variability. Regarding the methodological axis, the in-depth analysis of answers to a single question on ever asthma repeated 7 times over 13 years in the E3N study has shown that apparently inconsistent succession of answers (positive and negative) could capture part of the medium-term variability of asthma activity, suggesting the usefulness of such approach to improve the characterization of asthma expression over time. In a context of growing interest for perceived health, a simple retrospective self-assessment of 10-year change in respiratory health has been shown to provide complementary insights to classical epidemiological and clinical tools to describe the long-term trajectory of asthma, and could predict part of the asthma evolution. Following a recent meta-analysis including 6 European cohorts (23000 participants), in which results suggest a deleterious effect of chronic ambient air pollution on asthma incidence in adults, an analysis investigated the evolution of asthma medication dispensations over 4 consecutive years, in relation with air pollution. Among the women with asthma in the E3N study, an increased estimated exposure to outdoor nitrogen dioxide and particles was associated with increased rate of controller dispensations over time, suggesting the long-term effect of air pollution on asthma progression. In conclusion, results of the thesis showed that simple tools such as several repeated answers to a single question on asthma and the self-assessment of long-term change in respiratory health may be useful in order to better characterize the variability of asthma expression over the long term, as a complementary approach alongside with classical tools. Combined with the literature, results of the thesis support the deleterious impact of chronic air pollution on progression of asthma and strengthen the need of public health interventions to reduce air pollutants concentration.
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Electrofluidized beds in the control of fly ash

Alexander, Jeffrey Carl January 1978 (has links)
Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Vita. / Includes bibliographical references. / by Jeffrey C. Alexander. / Ph.D.
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Estudo da emissão da frota de veículos diesel e ciclo Otto, sem conversores catalíticos, nos municípios de Sorocaba e Votorantim / Study of the emission of the fleet of vehicles diesel and cycle Otto, without the catalytic converters in the cities of Sorocaba and Votorantim

Oliveira, Antonio Carlos Seidl 29 October 2009 (has links)
Este trabalho avalia por meio de um IEV - Inventário de Emissão Veicular, a contribuição dos veículos automotores na poluição do ar, nos municípios de Sorocaba e Votorantim, dando ênfase às suas características de frota e posição geográfica, seus impactos, quantificação e qualificação de emissão de poluentes, através de experimentos com a utilização de diesel metropolitano - B2 e biodiesel - B100 (soja), como combustível nos veículos equipados com motores de ignição por compressão (motor diesel), em substituição total ou parcial ao diesel existente no mercado nacional e a utilização de gasolina padrão da Petrobrás e de AEHC - ácool etílico hidratado combustível em veículos flex equipados com motores de ignição por centelha (motor ciclo Otto), sem os conversores catalíticos, buscando identificar as condições mais próximas da realidade da manutenção da frota. Para este trabalho, considera-se que os poluentes de interesse são o monóxido de carbono (\'C\'O\'), os hidrocarbonetos (\'H\'C\'), os óxidos de nitrogênio (\'N\'O IND.X\'), dióxido de carbono (\'C\'O IND.2\'), hidrocarbonetos sem metano (\'N\'M\'H\'C\'), aldeídos, formaldeídos e acetaldeídos. A análise dos dados obtidos nos experimentos, sem a utilização de conversor catalítico, utilizando gasolina padrão e AEHC - álcool etílico hidratado combustível, com relação aos limites L-4 do Proconve, demonstrou que os fatores de emissão (FE) obtidos, com gasolina padrão, resultaram em aumento em torno de 184% para \'C\'O\', 167% para \'H\'C\', 680% para \'N\'O IND.X\', 468% para \'N\'M\'H\'C\' e 23% para aldeídos, já para os FE obtidos com AEHC - álcool etílico hidratado combustível, resultaram em aumento em torno de 150% para \'C\'O\', 138% para \'H\'C\', 330% para \'N\'O IND.X\', 434% para \'N\'M\'H\'C\' e 405% para aldeídos. A simulação das emissões da frota real de modelos ciclo Otto e diesel em estudo sem a utilização de conversores catalíticos, ou seja, para 317.539 veículos, sendo 75.294 movidos à AEHC - álcool etílico hidratado combustível, 157.694 movidos à gasolina padrão, 16.042 movidos à biodiesel metropolitano B2, 64.730 tipo motocicletas movidas à gasolina, excluindo-se 3.779 veículos diversos entre reboques e semi-reboques, foi constatado que, as emissões totais seriam de 21.628,525 t/ano de \'C\'O\', 3.011,947 t/ano de \'H\'C\', 5.321,934 t/ano de \'N\'O IND.X\', 540.500,022 t/ano de \'C\'O IND.2\', 2.660,792 t/ano de \'N\'M\'H\'C\', 89,253 t/ano de formaldeídos, 138,565 t/ano de acetaldeídos e 227,818 t/ano de aldeídos. A simulação das emissões da frota real de modelos ciclo Otto e diesel em estudo sem a utilização de conversores catalíticos, ou seja, para 317.539 veículos, sendo 75.294 movidos à AEHC - álcool etílico hidratado combustível, 157.694 movidos à gasolina padrão, 16.042 movidos à biodiesel B100, 64.730 tipo motocicletas movidas à gasolina, excluindo-se 3.779 veículos diversos entre reboques e semi-reboques, foi constatado que, as emissões totais seriam de 21.628,425 t/ano de \'C\'O\', 3.011,947 t/ano de \'H\'C\', 5.302,977 t/ano de \'N\'O IND.X\', 540.875,538 t/ano de \'C\'O IND.2\', 2.660,792 t/ano de \'N\'M\'H\'C\', 91,039 t/ano de formaldeídos, 138,828 t/ano de acetaldeídos e 229,868 t/ano de aldeídos. Os resultados obtidos durante os experimentos, demonstram que uma manutenção inadequada, torna ineficaz qualquer ganho ambiental obtido, tendo em vista a crescente ampliação da frota existente, baseada em políticas públicas equivocadas, as quais, continuam a incentivar a aquisição de veículos particulares em detrimento do sistema de transporte público, o qual continua ineficiente, além de caro para os padrões econômicos da população. / This study evaluates by means of a IEV - inventory of vehicle emission to propagate, the contribution of motor vehicles in air pollution in the cities of Sorocaba and Votorantim, of the emphasis to the characteristics of the fleet and the geographic position of these cities, to the impacts of these characteristics, the quantification and qualification of the emission of pollutants, through experiments with the use of diesel metropolitano - B2 and biodiesel - B100, as combustible in vehicles equipped with engines of ignition for compression (motor diesel), in total or partial substitution to existing diesel in national market, and gasoline standard of Petrobras and AEHC - combustible hidrated ethyl alcohol and its mixtures in equipped vehicles flex with engines of ignition for flash (cycle Otto motor), without the catalytic converters; searching to identify the conditions next to the reality of the maintenance of the fleet. For this work, it is considered that the interest pollutants are the carbono monoxide (\'C\'O\'), hidrocarbons (\'H\'C\'), the nitrogen oxides (\'N\'O IND.X\'), carbono dioxide (\'C\'O IND.2\'), non-methane hydrocarbons (\'N\'M\'H\'C\'), aldehydes, formaldehydes and acetaldehydes. The analysis of the data gotten in the experiments, without the use of catalytic converter, using gasoline standard and AEHC - hydrated ethilic alcohol, with regard to the L-4 limits of the Proconve, demonstrated that the factors of emission (FE) gotten, with gasoline standard, had resulted in increase around 184% for \'C\'O\', 167% for \'H\'C\', 680% for \'N\'O IND.X\', 468% for \'N\'M\'H\'C\' and 23% for aldehydes, already for the FE gotten with AEHC, had resulted in increase around 150% for \'C\'O\', 138% for \'H\'C\', 330% for \'N\'O IND.X\', 434% for \'N\'M\'H\'C\' and 405% for aldehydes. The simulation of the emissions of the real fleet of models cycle Otto and diesel in study without the use of catalytic converters, that is, for 317.539 vehicles, being 75.924 moved to the AEHC, 157.694 moved by gasoline, 16.042 moved by the metropolitan biodiesel B2, 64.730 type motorcycles moved by the gasoline, abstaining itself 3.779 diverse vehicles between tows and semitrailers, was evidenced that, the total emissions would be of 21.628,525 tons per year (tpy) of \'C\'O\', 3.011,947 tpy of \'H\'C\', 5.231,934 tpy of \'N\'O IND.X\', 540.500,022 tpy of \'C\'O IND.2\', 2.660,792 tpy of \'N\'M\'H\'C\', 89,253 tpy of formaldehyde, 138,565 tpy for acetaldehyde and 227,818 tpy for aldehyde. The simulation of the emissions of the real fleet of models cycle Otto and diesel in study without the use of catalytic converters, that is, for 317.539 vehicles, being 75.294 moved by the AEHC, 157.694 moved by gasoline, 16.042 moved by the biodiesel B100 from syo bean oil, 64.730 type motorcycles moved by the gasoline, abstaining itself 3.779 diverse vehicles between tows and semitrailers, was evidenced that, the total emissions would be of 21.628,425 tpy of \'C\'O\', 3.011,947 tpy of \'H\'C\', 5.302,977 tpy of \'N\'O IND.X\', 540.875,538 tpy of \'C\'O IND.2\', 2.660,792 tpy of \'N\'M\'H\'C\', 91,039 tpy of formaldehyde, 138,828 tpy for acetaldeíhyde and 229,868 tpy for aldehydes. The results obtained during the experiments show that inadequate maintenance, makes ineffective any environmental gains achieved, with a view to increasing expansion of the existing fleet, based on misguided public policies, which continue to encourage the purchase of cars at the expense of public transport system, which remains inefficient, and expensive for the economic standards of the population.

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