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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.
191

Optical diagnostics and particulate emissions analysis of hydrogen-hydrocarbon combustion

Zhao, Huayong January 2012 (has links)
With the depletion of hydrocarbon fuels, the hydrogen-hydrocarbon combustion system provides a good solution for the transition period from a hydrocarbon-based energy sys- tem to a hydrogen-based energy system because of its desirable combustion characteristics and the low level of modification to current combustion systems. Though extensive re- search has been carried out to investigate the combustion process of hydrogen-hydrocarbon fuels, no experiments have been reported to study the Particulate Matter (PM) formations in hydrogen-hydrocarbon combustion systems. To measure the PM concentrations in a laminar diffusion flame, a new optical diagnostic technique, called Cone-Beam Tomographic Three Colour Spectrometry (CBT-TCS) has been developed to measure the spatially distributed temperature, soot diameter and soot volume fraction. This technique is based on the principle of three colour pyrometry, but uses a more rigorous light scattering model to calculate the soot diameter and soot volume fraction. The cone beam tomography technique has also been used to reconstruct the 3D property fields from the 2D flame images. The detailed theoretical principles, the exper- imental setup, the optical considerations, the reconstruction algorithm and the sensitivity analysis are all introduced. The CBT-TCS technique has been successfully applied to several laminar diffusion flames to study the PM formation. The temperature and soot volume fracction profiles measured by CBT-TCS for a ethylene laminar diffusion flame are consistent with the data reported by Snelling et al. [77]. The helium-ethylene-air flame tests show that adding helium reduces the PM formation (due to the dilution effect). The hydrogen-ethylene-air flame tests show that adding hydrogen is more effective in reducing the PM formation due to the combined effect of dilution and direct chemical reaction. A PM sampling system has also been de- veloped to verify the PM size distributions measured by CBT-TCS. The comparison results show that the CBT-TCS tends to overestimate the particle size. Several optical engine experiments have also been undertaken to investigate the effect of adding hydrogen on the PM emissions from a Gasoline Direct Injection (GDI) engine. The hydrogen-ethylene engine tests show that adding hydrogen can reduce the PM emissions without sacrificing the power output. The hydrogen-base fuel (65% isooctane and 35% toluene) tests show that adding hydrogen can improve the combustion stability and reduce the PM emissions, especially at low load. Adding 5% stoichiometric of hydrogen can reduce the total PM number concentration by 90% for a stoichiometric mixture and 97% for richer mixture at low load. At high load, adding 10% stoichiometric of hydrogen can also reduce the total PM number concentration by 85% for richer mixture but has little effect upon the stoichiometric mixture.
192

Investigating the effect of an intervention on novice science teachers topic specific pedagogical content knowledge.

Pitjeng, Ramatsobane Judith 19 May 2015 (has links)
The lack of teaching experience in uncertified teachers leaves them with little or no understanding of the transformation of Content Knowledge (CK) at their disposal. This transformation of CK is termed Pedagogical Content Knowledge (PCK) and it is known to develop through practice. Therefore, reflective analysis of lessons taught by these teachers is important. Research has also shown that they are often not supported as they embark on their teaching career. Therefore, the study investigated the influence of an intervention on novice unqualified graduate teachers’ (NUGTs) Topic Specific Pedagogical Content Knowledge within a specific topic – the particulate nature of matter. The construct, Topic Specific PCK was the theoretical framework of my study and it consists of five topic specific categories that collectively enable transformation of content knowledge. The categories are: (1) learner prior knowledge (2) curricular Saliency (3) what is difficult to teach (4) representations and (5) conceptual teaching strategies. For measuring the quality of Topic Specific PCK, a new tool based on the topic of the particulate nature of matter was developed. The Topic Specific PCK tool was then validated using a group of 11 practising science teachers. The tool was scored using a rubric that is in line with the five categories, which are rated on a four point scale, where 1 stands for limited PCK and 4 is exemplary PCK. The research design followed in my study was mixed-methods research (MM). The study involved 16 novice teachers recruited by Teach South Africa working together with the Department of Education. The teachers hold university degrees, have done chemistry for a minimum of one year during the course of their degree and have no teaching qualifications. Four of the teachers who taught the particulate nature of matter were selected as case study teachers. Data was collected through a number of tools, including the newly designed Topic Specific PCK test on particulate nature of matter, a CK test and Content Representations (CoRes) which were all adapted from existing tools and thus considered validated. The case study teachers were observed while teaching particulate nature of matter and their lessons were analysed. All the teachers were tested before and after the professional development intervention (PDI). The findings show that the quality of Topic Specific PCK and CK in particulate nature of matter was improved in all NUGTs. The greatest improvement was observed in the NUGTs who taught the topic directly. This improvement was attributed to the experience of teaching the topic directly or teaching related concepts that need understanding of it. The improvement was observed in all the NUGTs, showing the effect of indirect experience. This can be deduced from their improved CoRe which forced the NUGTs to engage with the construct and also through the positive significant improvement in CK and Topic Specific PCK results. Finally, I suggest that although interventions like PDI have the potential to produce science teachers, care should be exercised in making assumptions about their CK and knowledge for teaching, and training programmes need to pay attention to both CK and Topic Specific PCK.
193

Evaluation de différentes stratégies de prévention des incompatibilités médicamenteuses dans le contexte de la perfusion continue / Evaluation of different strategies to prevent drug incompatibilities during continuous infusion

Perez, Maxime 30 September 2015 (has links)
La perfusion intraveineuse occupe une large place dans les services de soins cliniques. Les patients reçoivent de nombreux médicaments simultanément dans la même voie centrale, où des problèmes de compatibilité entre les médicaments peuvent survenir. La maitrise de ces incompatibilités médicamenteuses, génératrices de particules, représente donc un enjeu majeur dans la prise en charge des patients polymédiqués.La première partie de ce travail est une analyse de la littérature portant sur les incompatibilités médicamenteuses et leurs principales conséquences sur le plan clinique. A ce titre, un chapitre est dédié à l’ensemble des moyens de prévention de ces problèmes, parmi lesquels l’usage de filtres en ligne de perfusion ou de dispositifs de perfusion multi-lumières.La première partie de nos travaux expérimentaux est consacrée à l’évaluation de la filtration terminale comme stratégie de prévention de l’administration de particules aux patients. Dans ce contexte, nos travaux ont porté sur le noircissement des filtres en ligne observé dans un service de réanimation néonatale. L’objectif était de définir la nature de l’incompatibilité en cause et de s’assurer, dans un second temps, de l’efficacité des filtres malgré les phénomènes de noircissement. Les filtres ont été examinés par microscopie électronique et comptage particulaire. Un aminogramme de la nutrition parentérale a également été réalisé. Une interaction spécifique a été mise en évidence entre un acide aminé (la cystéine) et un oligoélément (le cuivre) dans les poches. De plus, le maintien de la fonction des filtres en ligne a été démontré.La seconde partie de nos travaux est axée sur l’évaluation de l’intérêt d’un dispositif médical multi-lumières innovant dans la prévention des incompatibilités médicamenteuses. Le premier travail mené dans cette thématique a montré in vitro son intérêt à prévenir la survenue d’incompatibilités physiques entre plusieurs associations médicamenteuses, allant de deux à six médicaments administrés simultanément. Nos résultats indiquent que la conception de ces nouveaux dispositifs de perfusion et notamment leur géométrie interne permet de minimiser le temps de contact entre les produits, et ainsi d’améliorer la compatibilité entre les produits, au même titre que le type de solution d’hydratation. Le second travail consistait à poursuivre l’évaluation de ces dispositifs de perfusion multi-lumières en reproduisant un protocole de perfusion utilisé habituellement en hématologie pédiatrique et associant plusieurs médicaments incompatibles à l’origine de précipité. Un comptage particulaire réalisé de manière dynamique a permis de montrer que l’emploi de ces dispositifs permettait de réduire significativement la charge particulaire administrée aux patients, en comparaison avec les dispositifs standard de perfusion (rampes de robinets).Les résultats de l’ensemble de nos travaux sont prometteurs pour l’amélioration de la prise en charge des patients. Ils doivent être maintenant confirmés au travers d’une étude clinique. / Intravenous infusions are extensively used in clinical wards. Patients simultaneously receive many drugs through a limited number of venous accesses, thus increasing the risk of physical drug incompatibilities. Preventing incompatibility is therefore important for the safe administration of injectable drugs of polymedicated patients.The first part of this work consisted in analysing published literature on drug incompatibilities and their clinical consequences. This chapter includes a review of tools preventing drug incompatibilities, which include in-line filtration or the use of multi-lumen infusion sets.The first part of our experimental work is dedicated to the evaluation of terminal in-line filtration for preventing the injection of drug particles to patients. In this context, our research has focused on the blackening of in-line filters, which have been observed during the infusion of binary parenteral nutrition (BPN) delivered in a neonatal intensive care unit. The purposes of our study were, first, to examine the elemental content of precipitates isolated from infused BPN bags and so determine the main physicochemical interactions occurring in them and, second, to evaluate the blackening effect of in-line filters on filtration capacity. Filter membranes were examined by scanning electron microscopy and energy dispersion spectroscopy. Amino acid (AA) profiles were obtained from BPN mixtures to determine the concentrations of each AA. A specific interaction was identify between cysteine and copper in our BPN. Despite the gradual blackening of in-line filters during BPN bag infusion, the filter membranes continued to filter solutions efficiently and safely.The second part of our work focused on the assessment of the impact of new multilumen infusion access devices on the occurrence of known drug incompatibility.The first study used a well-documented incompatible combination of two to six drugs and three different carrier fluids. The multilumen infusion access device was able to prevent the occurrence of drug incompatibilities in nearly half of the drug combinations tested. This study confirmed that the characteristics of an infusion device have an impact on drug physical incompatibilities. The main hypothesis is those fluid dynamics differ according to infusion device and accesses, which modify the contact time between drugs and the infusion vehicle.The second in vitro study focused on a pediatric multidrug protocol for patients diagnosed with lymphoblastic leukemia and receiving allogeneic transplantation. A dynamic particle count test was used over 24 hours to evaluate the overall particulate contamination. The use of a multi-lumen infusion set reduces significantly overall particulate contamination compared to the standard infusion set.These results pave the way to performing a randomized controlled clinical trial assessing the multilumen infusion access device.
194

Évaluation de l’exposition du patient adulte aux particules issues des incompatibilités entre médicaments injectables utilisés en anesthésie et réanimation / Assessment of particulate exposure induced by drug incompatibilities during continuous drug infusion in critically ill adult patients

Benlabed, Abdelmalik 19 December 2018 (has links)
Ce travail de doctorat s’inscrit dans un projet de recherche destiné à évaluer la charge particulaire issue des incompatibilités physico-chimiques d’origine médicamenteuse de patients admis en réanimation pour un état de choc septique ou un syndrome de détresse respiratoire aigüe. Le corollaire est de faire le lien avec la survenue de certaines complications (syndrome inflammatoire et dysfonction d’organe) susceptibles de menacer le pronostic vital. En effet, la dysfonction microcirculatoire caractéristique de ces patients pourrait être majorée par la contamination particulaire aboutissant ainsi à une aggravation de l’hypo-perfusion tissulaire et à la survenue du syndrome de défaillance multi viscérale.La première partie de ce travail a consisté en une analyse de la littérature portant sur les incompatibilités médicamenteuses et leurs principales conséquences cliniques sous forme d’une revue systématique. Un des messages essentiels est l’intérêt grandissant de la filtration en ligne comme moyen de prévention de la contamination particulaire bien mis en évidence par certains essais contrôlés randomisés en particulier pédiatriques.La seconde partie de ce travail était de mener, dans une première phase, une étude d’observation clinique au lit du malade des dispositifs de perfusion intraveineux habituellement utilisés et des médicaments le plus souvent administrés à ces patients de réanimation du CHU de Lille. La deuxième phase consistait à reproduire in vitro le montage de perfusion utilisé en clinique avec les différentes solutions médicamenteuses dans le but de quantifier la charge particulaire à laquelle sont exposés les patients. Le comptage particulaire a été réalisé de manière dynamique, selon une technique innovante, grâce à un analyseur de particule connecté au montage de perfusion.Ce travail nous a permis finalement d’évaluer le risque particulaire pour ces patients fragiles et de proposer une stratégie de prévention des incompatibilités médicamenteuses. / Our PhD work aimed to evaluate the particulate exposure induced by drug incompatibilities in patients admitted in ICU for a septic shock or acute respiratory distress syndrome. The purpose was to establish a link with the occurrence of certain complications (inflammatory syndrome and organ dysfunctions) susceptible to aggravate life threatening. Indeed, the microcirculatory dysfunction characteristic of these patients could be increased by the particulate contamination, compromising tissue perfusion and leading to the occurrence of multi organ failureThe first part of this study consisted in a systematic literature review on the clinical implications of drug incompatibilities. One of the essential messages is the growing interest of inline filtration to prevent particulate contamination, highlighted by randomized controlled trials especially in pediatric ICU.The second part of the study was to conduct, in a first phase, an observational study, at the ICU patients’ bedsides, of the commonly used intravenous drugs and infusion sets. The second phase was to reproduce in vitro the previous observed infusion lines using the observed drugs combination, in order to quantify the particulate exposure, during a simulated 6-hour infusion period. The particle counting was performed using an innovative dynamic image analysis device.Our work indicates the amount of particulate matter potentially administered to critically-ill adult patients and paves the way to a strategy of prevention of drug incompatibilities.
195

Resposta molecular do endotélio pulmonar à exposição aguda de material particulado  fino / Molecular response of pulmonary endothelial cells to acute exposure to fine particulate matter

Alameddine, Mirna 03 March 2010 (has links)
Estudos epidemiológicos estabelecem uma associação evidente entre poluição do ar e o aumento de morbimortalidade cardiovascular e respiratória. No entanto, os mecanismos moleculares subjacentes aos efeitos do material particulado fino (MP2,5) sobre o organismo ainda estão pouco esclarecidos. O objetivo deste trabalho foi caracterizar o impacto da exposição ao MP2,5 sobre a biologia do endotélio pulmonar e do coração, através da avaliação do perfil de expressão gênica por microarray. Camundongos adultos fêmeas foram anestesiados e submetidos à instilação intratraqueal de MP2,5 (grupo exposto) ou veículo (grupo controle). Os animais foram sacrificados 12 a 18 horas após a instilação e pulmão, coração e sangue da veia cava inferior foram coletados. Os pulmões foram dissociados com colagenase tipo I e células endoteliais foram positivamente selecionadas por captura imuno-magnética através de micro-ímãs acoplados a anti-CD31. O cRNA derivado de endotélio pulmonar e de coração total foi hibridizado em membrana de microarray de baixa densidade desenhada para representar genes relevantes à biologia endotelial. Os genes encontrados diferencialmente expressos no pulmão foram Itgb1, Cxcl1, Tnf, Ecgf1 e Tnfaip3 (hiper-expressos em expostos a MP2,5) e Enpep, Pdgfra, Gzmb, Birc2, Npr1, Angpt1, Cxcl5 e Il7 (hipo-expressos). Não foi possível realizar análise de inferência estatística de membranas do coração neste trabalho. Não houve diferença estatisticamente significativa entre os grupos exposto e controle na contagem sangüínea de neutrófilos, linfócitos ou plaquetas, apesar dos dois grupos apresentarem plaquetose. Os achados indicam que MP2,5 altera a transcrição de genes envolvidos não só na inflamação e estresse oxidativo, mas também no tônus e remodelamento vascular, que podem ser os responsáveis pelos efeitos cardiovasculares agudos do MP2,5 / Epidemiological studies establish a clear association between air pollution and increased cardiovascular and respiratory morbidity and mortality. However, the molecular mechanisms underlying the effect of fine particulate matter (PM2,5) are still poorly understood. The aim of this study was to characterize the impact of exposure to PM2,5 on the biology of pulmonary endothelium and the heart, through the assessment of gene expression profiling by microarray. Adult female mice were anesthetized and submitted to intratracheal instillation of either PM2,5 (challenged group) or vehicle (control group). The animals were sacrificed 12 to 18 hours after instillation and lung, heart and blood samples from the inferior vena cava were collected. The lungs were dissociated with collagenase type I and endothelial cells were positively selected by immuno-magnetic capture through microbeads coupled to anti-CD31. The cRNA derived from the pulmonary endothelial cells and heart were hybridized to low-density microarray designed specifically to represent genes relevant to endothelial biology. Genes found differentially expressed in the lung were Itgb1, Cxcl1, Tnf, Ecgf1, and Tnfaip3 (over-expressed in challenged group) and Enpep, Pdgfra, Gzmb, Birc2, Npr1, Angpt1, Cxcl5 and IL7 (under-expressed). It was not possible to perform statistical inference of heart samples in this study. There was no statistically significant difference between challenged and control groups in blood counts of neutrophils, lymphocytes or platelets, despite both groups presented increased number of platelets. The findings indicate that PM2,5 alters transcription of genes involved not only in inflammation and oxidative stress, but also in vascular tonus and remodeling, which may be responsible for the acute cardiovascular effects of PM2,5
196

Caracterização de ambientes internos da região central de São Carlos/SP: material particulado e poluição sonora / Characterization of internal environments of the region central Sao Carlos/SP: particulate material and noise

Schornobay, Elaine 25 May 2012 (has links)
Este trabalho teve como objetivo avaliar a qualidade ambiental interna de lojas da região central na cidade de São Carlos/SP. Foram monitorados os seguintes parâmetros: concentração e análise química de MP10 e de MP2,5, \'CO IND.2\', níveis de ruído, temperatura e umidade relativa do ar. A coleta de dados foi realizada de maneira simultânea em ambientes internos e externos de quatro lojas do centro da cidade por um período de oito horas diárias, das 9 h às 17 h. Dois pontos estavam localizados de frente para vias de grande circulação de veículos e dois no calçadão da cidade (sem trânsito de veículos). Os valores de concentração, tanto de MP10 como de MP2,5, se apresentaram, na maior parte dos dias de coleta, com os valores internos superiores aos externos. Para o período chuvoso, em que foi realizado o maior número de coletas, os valores de concentração não ultrapassaram os limites estabelecidos pela OMS, de 25 \'mü\'g/\'M POT.3\' para o MP2,5 e de 50 \'mü\'g/\'M POT.3\' para o MP10. Quanto à análise química, foi observado que não há diferenças significativas entre os ambientes interno e externo. Sendo que, em ambos os ambientes, foram encontrados Si, S, Ca, Fe, Al, K e Cu, elementos comumente observados em áreas urbanas. Em relação ao \'CO IND.2\', o seu monitoramento não se mostrou relevante, já que todos os ambientes monitorados realizavam trocas de ar com o ambiente externo de forma natural, dessa forma a concentração não atingiu valores preocupantes. Os níveis de poluição sonora monitorados no ambiente externo foram superiores aos do ambiente interno em todos os dias monitorados. Os pontos de monitoramento que ficavam direcionados para as vias de circulação de veículos apresentaram valores superiores aos encontrados no calçadão da cidade. Em todos os dias monitorados, os valores de ruído dos ambientes interno e externo não apresentaram acordo com o padrão estabelecido pela NBR 10.151/2.000, de 50 dB(A) e 60 dB(A), respectivamente. Sendo que os valores externos ficaram entre 61 dB(A) e 66,8 dB(A) e, para o ambiente interno, os valores variaram de 53,9 dB(A) a 63,6 dB(A). A temperatura e a umidade relativa do ar apresentaram variações ao longo do dia e, de acordo com a RE/ANVISA nº 09/2003 e o índice HI, a maioria dos dias monitorados sugere sensação de desconforto térmico aos ocupantes desses locais. / This study aimed to evaluate the indoor environmental quality of shops in the central region in São Carlos/SP. The following parameters were monitored: the concentration and chemical analysis of MP10 and MP2,5, \'CO IND.2\', noise levels, temperature and relative humidity. Data collection was performed simultaneously in internal and eternal environments of four stores in the center of town for period of eight hours daily, from 9 am to 5 pm. Two points were located in front of large circulation routes for vehicles and two on the sidewalk of the city (no vehicle traffic). The values concentration both PM10 and PM2,5 are presented, in most days of collection, with the internal values higher than the outside. For the rainy season, which was held in the greatest number of samples, the concentration values did not exceed the limits set by OMS of 25 \'mü\'g/\'M POT.3\' for MP2,5 and 50 \'mü\'g/\'M POT.3\' for MP10. In the chemical analyses, it was not observed significant differences between the internal and external environments, since in both environments were found Si, S, Ca, Fe, Al, Cu and K, elements commonly seen in urban areas. In relation to the \'CO IND.2\' monitoring was not relevant, since all monitored environments performed ais exchanges with the external environment in a natural way, producing values concentration not concern. The noise levels monitored in the external environment were superior to the internal environment every day. The monitoring points directed to the traffic routes of vehicles had higher values than those found on the sidewalk of the city. On each day the monitored noise vaues of the internal and external environments not presented inside of the standard established by NRB 10.151/2000 of 50 dB(A) e 60 dB(A), respectively, since external values were between 61 dB(A) and 66,8 dB(A), and the internal environment values ranged from 53,9 dB(A) and 63,6 dB(A). The temperature and relative humidity showed variations thoughout the day, and according to RE/ANVISA nº 09/2003 and the index HI, most of the days monitored suggests thermal discomfort to the occupants of these places.
197

Desafios da gestão da qualidade do ar: dinâmicas e padrões de qualidade do ar no município de Cubatão e entorno / Challenges of the air quality management: dynamics and standards of the air quality in the City of Cubatão and surroundings

Cheng, Mônica Silveira e Costa 06 July 2015 (has links)
Município de Cubatão passou por mudanças significativas em seu cenário desde 1950, passando de uma região rural para industrial, com impacto ambiental significativo. Este projeto tem por objetivo analisar o conjunto de ações relacionadas à gestão ambiental da qualidade do ar, entre 1980 e 2013, no Município de Cubatão e seu entorno, considerando possibilidades de respostas na tomada de decisão e ações para controle da qualidade do ar, particularmente referente ao material particulado (MP10). O percurso metodológico da investigação considerou: legislação referente ao período, materiais divulgados na imprensa, banco de dissertações e teses acadêmicas e etapa de pesquisa empírica, com o desenvolvimento de conceitos que equacionem as questões de tráfego de caminhões e qualidade do ar em Cubatão e entorno. Como resultado desta pesquisa pôde-se identificar os principais elementos-chave a serem considerados e propor protótipo, com uma nova abordagem logística para o transporte de grãos na região, que pode auxiliar no controle sobre os índices de poluição do ar, em específico, oparâmetro material particulado (MP10). / The scenario of the City of Cubatão has changed significantly since 1950, going from a rural region to an industrial one, with a significant environmental impact. The objective of this project is to analyze the actions related to the environmental management of air quality, from 1980 to 2013, in the City of Cubatão and its surrounding, considering potential responses in the decision-making and actions for air quality control, especially regarding the particulate matter (PM10). The research methodology has taken into consideration the legislation for the period, press publications, academic dissertations and theses database, and an empirical research stage, with the development of concepts to assess the truck traffic and air quality issues in Cubatão and surroundings. As a result of this research, the key elements to be taken into consideration were identified and a prototype, with a new approach on the grain transport logistics in the region, was proposed, which can assist the control of air pollution index, specially, the particulate matter parameter (PM10).
198

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
199

Análise crítica dos critérios de seleção de respiradores para particulados em ambientes de mineração. / Critical analyses of Brazilian particulate respirator selection logic for mining workers.

Gabas, Glaucia Christine Cortelini 04 June 2008 (has links)
Várias etapas dos processos de mineração geram quantidades significativas de materiais particulados, também chamados de aerodispersóides que, dependendo de suas características químicas e físicas, são importantes causadores de doenças ocupacionais denominadas pneumoconioses. Para proteger os trabalhadores desses ambientes, algumas medidas de controle podem ser adotadas. Dentre elas, a medida mais comum é através da utilização de respiradores aprovados. Neste trabalho é apresentada uma análise crítica dos procedimentos de seleção de respiradores para particulados estabelecidos no documento intitulado Programa de Proteção Respiratória (PPR) e proposta a adoção de outros critérios técnicos importantes para trabalhadores de ambientes de mineração. Através do levantamento bibliográfico em acervos nacionais e internacionais, regulamentações vigentes, coleta de dados em minerações e experiência profissional da autora foi possível situar o ambiente de mineração em relação à presença de materiais particulados, analisar a lógica de seleção relacionada com os requisitos legais vigentes no Brasil e identificar os respiradores mais comumente empregados nos ambientes de mineração. Como resultado deste trabalho foi possível discutir sobre o nível de proteção respiratória a que os trabalhadores de minerações brasileiras estão sujeitos e sugerir o uso de tipos de respiradores para algumas situações de exposição. / Significant amounts of particulate matter, also called aerosols, are generated in many steps of mining and depending on its chemical and physical characteristics they are important agents that causes occupational diseases, named pneumoconioses. In order to protect the workers of this environment, some controls can be adopted. Among them, the most common control is the use of approved respirators. In this work is presented a critical analysis of particulate respirators selection procedures that are established at Respiratory Protection Program document and indicated the adoption of other important technical criteria for mining workers. Through the national and international bibliographic information, current regulations, data collection in mining industries and author professional expertise it was possible creating a mining workplace overview related to the presence of particulate matter, analyzing the respirator selection logic considering the Brazilian legal requirements and identifying the most common respirators applied at mining workplace. As a result of this work it was possible to discuss about the respiratory protection level that Brazilian mining workers are subjected and to suggest the use of respirators in some exposure situation.
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Análise dos contaminantes biológicos presentes no material particulado (PM2,5) de amostras da região metropolitana de São Paulo / Analysis of biological contaminants in Particulate Matter (PM2.5) of Sao Paulo

Coelho, Cristiane Degobbi 05 August 2009 (has links)
INTRODUÇÃO: A poluição do ar traz diversos efeitos à saúde e, em particular, o material particulado menor do que 2,5 &#956;m (PM2,5), está associado ao aumento das taxas de morbidade e mortalidade devido a doenças cardiorespiratórias. A maioria dos estudos foca apenas na composição química do material, porém os componentes do bioaerossol podem ser responsáveis por aproximadamente 22% da massa total. OBJETIVOS: Nesse estudo, objetivamos determinar a contribuição relativa de fungos e endotoxinas (constituinte da parede celular de bactérias gram-negativas) no PM2,5 e verificar possíveis efeitos inflamatórios locais devido à exposição a fungos e PM2,5 em ratos. MÉTODOS: O estudo foi dividido em três partes: 1) comparação de metodologias de coleta de fungos em amostradores de ar de curta e longa duração realizada em ambiente externo e em ambiente de concentrador de partículas ambientais em Boston, MA. 2) Coleta de 4 tipos de filtros a partir de amostrador de ar de PM2,5 utilizados para análise separadamente de fungos, quantificação de endotoxinas, análise de elementos químicos e extração para instilação em ratos em São Paulo. Dados meteorológicos também foram coletados. 3) Instilação intratraqueal de PM2,5 e fungos originários da atmosfera de São Paulo em ratos machos Wistar divididos em 3 grupos: A (administração de 6,3x102 esporos/&#956;g de PM2.5), B (18x102 esporos/&#956;g de PM2.5) e C (controle - instilação a partir de extração de filtro branco). O sacrifício foi feito após 24 horas da exposição, depois da retirada do lavado broncoalveolar para contagem total e diferencial de leucócitos, além de quantificação de citocinas de respostas TH1 e TH2. RESULTADOS: O estudo de comparação de metodologias mostrou que, entre os amostradores de ar de curta duração, Personal Burkard recuperou maior diversidade e concentração do que Andersen (p<0,05). Entre os amostradores de longa duração, Recording Burkard mostrou-se o melhor em termos de diversidade e concentração de esporos do que filtros MCE (p<0,05). Também observamos que os fungos representaram relevante porção do PM2,5, chegando a concentrações de 2159 esporos/&#956;g em ambiente de Concentrador de Partículas alocado em Boston, MA. A segunda parte do estudo mostrou novamente que os fungos representam porção relevante do PM2.5 alcançando valores médios de até 1345 esporos/&#956;g de PM2,5 a partir de coletas da atmosfera de São Paulo. Da mesma forma, endotoxinas foram obtidas em concentrações médias de 5,52 EU/&#956;g de PM2,5. Os modelos de regressão linear múltipla mostraram que a contagem total de fungos, de basidiósporos hialinos e de Cladosporium sp foi correlacionada positivamente com a presença do fator Ba/Ca/Fe/Zn/K/Si no PM2,5 (p<0,05). Os gêneros Penicillium/Aspergillus foram correlacionados positivamente à concentração de material particulado na atmosfera (p<0,05). Os ascósporos sem pigmentação foram correlacionados positivamente à umidade (p<0,05). As endotoxinas foram correlacionadas apenas à temperatura atmosférica (p<0,05). O modelo de instilação em animais mostrou que a administração de 6,3x102 esporos/&#956;g de PM2,5 foi responsável por um aumento na concentração de TNF e IFN no lavado broncoalveolar (p<0,05). Não foi observado o mesmo efeito quando a concentração de esporos foi de 18x102 esporos/&#956;g de PM2,5. Não foram observadas diferenças sgnificativas contagem total e diferencial de leucócitos. CONCLUSÕES: Fungos e endotoxinas são responsáveis por fração relevante do PM2,5. Esses contaminantes biológicos podem estar associados não apenas a fatores meteorológicos, mas também a elementos químicos presentes no Material Particulado, especialmente a elementos sinalizadores de tráfego de veículos e ressuspensão da crosta. Exposições a diferentes concentrações de fungos associados ao PM2,5 em ratos não sensibilizados podem levar a diferenças em respostas inflamatórias agudas, porém os mecanismos responsáveis por tais resultados devem ser objeto de estudos futuros. / INTRODUCTION: It is well known that air pollution is associated with health effects, particularly, particulate matter (PM) is correlated with increment in morbity and mortality by cardiorespiratory diseases. A lot of studies have focused on chemical characterization of PM, although components of bioaerosols may comprise nearly 22% of the total mass. OBJECTIVES: The aims of this study were to determine the relative contribution of fungi and endotoxin (component of cell wall in gram-negative bacteria) in PM2.5 and verify acute local inflammatory response due to fungi and PM2.5 exposure in rats. METHODS: The study was divided in 3 parts: 1) Comparison among short and long term samplers located outdoor and in Ambient Particle Concentrator located in Boston, MA. 2) Sampling of 4 different filters types analyzed for fungi, endotoxin, chemical composition and extraction for instillation experiments in Sao Paulo. Meteorological data were also collected. 3) Intratracheal instillation of PM2.5 and fungi in male Wistar rats, divided in 3 groups: A (administration of 6.3x102 spores/&#956;g of PM2.5), B (administration of 18x102 spores/&#956;g of PM2.5) and C (control - blank filter). The animals were sacrificed 24 hours after exposure to collect bronchoalveolar lavage. Total and differential counts of leukocytes as TH1 and TH2 cytokines quantification were assessed. RESULTS: Sampling techniques comparisons showed that, the short term sampler Personal Burkard was able to collect more diversity and concentration of spores than Andersen sampler (p<0.05). The long term sampler Recording Burkard was also able to collect more diversity and concentration of spores than MCE filters (p<0.05). We also observed that fungi contribution to PM2.5 was relevant, representing up to 2159 spores/&#956;g of PM2.5 in Ambient Particle Concentrator located in Boston, MA. The second part of the study demonstrated again that fungi represent a relevant portion of PM2.5, reaching average values of 1,345 spores/&#956;g of PM2.5 in Sao Paulo atmosphere. Also, endotoxin concentrations reached averages values of 5.52 EU/&#956;g of PM2.5. Multiple linear regression models showed that total fungi counts, hyaline basidiospores and Cladosporium sp were correlated with factor Ba/Ca/Fe/Zn/K/Si (p<0.05). The genera Penicillium/Aspergillus were correlated with PM2.5 mass (p<0.05). Colorless ascospores were correlated with relative humidity (p<0.05). Endotoxin was correlated only with temperature (p<0.05). Instilattion results showed that administration of 6.3x102 spores/&#956;g of PM2.5 was responsible for an increase in TNF and IFN in bronchoalveolar lavage (p<0.05). The same pattern wasn\'t observed when 18x102 spores/&#956;g of PM2.5 was administered. No significant differences were observed leucocytes total and differential counts. CONCLUSIONS: Fungi and endotoxin represent a relevant fraction of PM2.5. These biological contaminants can be associated not only with meteorological parameters, but with elementary composition, especially elements of traffic and crustal ressuspension. Acute exposure of non sensitized rats to different concentrations of fungi associated to PM2.5 might trigger different inflammatory responses, although the specific mechanisms remain unknown and further research is needed.

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