Made available in DSpace on 2014-12-17T14:10:23Z (GMT). No. of bitstreams: 1 BrunoGS_DISSERT_partes autorizadas.pdf: 2090858 bytes, checksum: 96c920960475d5970880d27da7b95ada (MD5) Previous issue date: 2011-05-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Knowledge of the native prokaryotes in hazardous locations favors the application of biotechnology for bioremediation. Independent strategies for cultivation and metagenomics contribute to further microbiological knowledge, enabling studies with non-cultivable about the "native microbiological status and its potential role in bioremediation, for example, of polycyclic aromatic hydrocarbons (HPA's). Considering the biome mangrove interface fragile and critical bordering the ocean, this study characterizes the native microbiota mangrove potential biodegradability of HPA's using a biomarker for molecular detection and assessment of bacterial diversity by PCR in areas under the influence of oil companies in the Basin Petroleum Geology Potiguar (BPP). We chose PcaF, a metabolic enzyme, to be the molecular biomarker in a PCR-DGGE detection of prokaryotes that degrade HPA s. The PCR-DGGE fingerprints obtained from Paracuru-CE, Fortim-CE and Areia Branca-RN samples revealed the occurrence of fluctuations of microbial communities according to the sampling periods and in response to the impact of oil. In the analysis of microbial communities interference of the oil industry, in Areia Branca-RN and Paracuru-CE was observed that oil is a determinant of microbial diversity. Fortim-CE probably has no direct influence with the oil activity. In order to obtain data for better understanding the transport and biodegradation of HPA's, there were conducted in silico studies with modeling and simulation from obtaining 3-D models of proteins involved in the degradation of phenanthrene in the transport of HPA's and also getting the 3-D model of the enzyme PcaF used as molecular marker in this study. Were realized docking studies with substrates and products to a better understanding about the transport mechanism and catalysis of HPA s / O conhecimento sobre os procariotos nativos em locais de risco favorece a aplica??o de biotecnologias para biorremedia??o. Estrat?gias independentes de cultivo, como metagen?mica, contribuem para aprofundar o conhecimento microbiol?gico, possibilitando estudos com organismos n?o cultiv?veis acerca do status microbiol?gico nativo e seu potencial papel na biodegrada??o de, por exemplo, Hidrocarbonetos Arom?ticos Polic?clicos (HAP s). Considerando o bioma de mangue uma interface fr?gil e cr?tica de fronteira com o oceano, este trabalho caracteriza a microbiota nativa de mangue com potencial biodegradador de HAP s utilizando um biomarcador molecular para detec??o e avalia??o da diversidade bacteriana em ?reas sob influ?ncia de ind?strias petrol?feras atrav?s da PCR-DGGE na Bacia Petrol?fera Potiguar (BPP). Foi escolhido um biomarcador molecular metab?lico, enzima PcaF, para detec??o de procariotos degradadores de HAP s. Com o biomarcador, fingerprints foram obtidos de amostras de Paracuru-CE, Fortim-CE e Areia Branca-RN, revelando a ocorr?ncia de flutua??es das comunidades microbianas de acordo com os per?odos de amostragem e em resposta ao impacto por petr?leo. Atrav?s da an?lise das comunidades microbianas frente ? interfer?ncia da ind?stria do petr?leo, em Areia Branca-RN e Paracuru-CE foi observado que o petr?leo ? determinante para a diversidade microbiana. Fortim-CE provavelmente n?o tem influ?ncia direta da atividade petrol?fera. No intuito de obter dados para o melhor entendimento do transporte e biodegrada??o de HAP s, foram desenvolvidos estudos in silico de modelagem e simula??o computacional a partir da obten??o de modelos 3-D de prote?nas envolvidas na degrada??o do fenantreno, no transporte de HAP s e tamb?m a obten??o do modelo 3-D da enzima PcaF. Estudos de dockings com substratos e produtos forneceram dados para o melhor entendimento sobre o mecanismo de transporte e cat?lise de HAP s

Camundongos AIRmax são resistentes e AIRmin susceptíveis à carcinogênese de pele por repetidas doses de DMBA. Apenas os AIRmin desenvolvem reação de hipersensibilidade de contacto (CHS) inicial seguida de tumores de pele e pulmão. O receptor aril hidrocarboneto (AHR) é importante no metabolismo do DMBA. Após ligação ao agonista este fator de transcrição aumenta a expressão de enzimas CYP450 necessários à sua metabolização. Nos AIRmin ocorreu um aumento do mRNA de IL1<font face=\"symbol\">b, TNF<font face=\"symbol\">a, IL6, TGF<font face=\"symbol\">b1 e CYP1B1 na pele às 48h após as doses de DMBA. Nos AIRmax não houve alteração. O aumento de expressão de citocinas e de P450 em AIRmin é coerente com a indução de CHS por DMBA dependente da ativação do AHR. Todos os AIRmax são homozigotos para o alelo Ahrd que confere resistência a CHS e carcinogênese enquanto os AIRmin portam o alelo Ahrb1 que confere susceptibilidade. Esta segregação alélica sugere a participação do Ahr como marcador ou gene que regula a carcinogênese e inflamação. Esta última hipótese foi confirmada pela análise de linkage dos genótipos Ahr parentais com o grau da inflamação em população F2 (AIRmax x AIRmin). Fatores genéticos ligados ao AHR e reações imunes específicas contribuem para a diferente susceptibilidade das linhagens à carcinogênese. / AIRmax mice are resistant and AIRmin susceptible to skin carcinogenesis by repeated DMBA doses. AIRmin mice developed initial contact hypersensitivity reaction (CHS) and late skin and lung tumors. The aryl hydrocarbon receptor (AHR) plays important roles in DMBA metabolism. Upon binding to agonist this transcription factor induces the expression of CYP P450 enzymes. Up regulated levels of IL1<font face=\"symbol\">b, TNF<font face=\"symbol\">a, IL6, TGF<font face=\"symbol\">b1 and CYP1B1 mRNAs were found in the skin of AIRmin at 48h after DMBA. In AIRmax the levels were similar to controls. The cytokine and P450 mRNA up regulation in AIRmin is coherent with CHS elicitation by DMBA dependent on AHR activation. All AIRmax were found homozygous for the Ahrd allele, which confers resistance to CHS and carcinogenesis, whereas all AIRmin are homozygous for the Ahrb1 allele, related to susceptibility. The allelic segregation in the lines suggests that Ahr is a marker or a gene involved in carcinogenesis and in inflammatory response control. This last hypothesis was confirmed by linkage analysis of Ahr parental genotypes with acute inflammation degree in F2 (AIRmax x AIRmin) population. The results point to genetic and molecular factors underlying the differential susceptibility of AIRmax and AIRmin mice to carcinogenesis.

Firefighters and asphalt pavers are exposed to polycyclic aromatic hydrocarbons (PAHs) during various work activities. The purpose of this study was to evaluate urinary PAH levels and compare these bio-monitoring levels among firefighters, asphalt pavers, and non-occupationally exposed individuals. The National Institute of Standards and Technology (NIST) urinary PAH levels were used for non-occupationally exposed controls. When compared to the NIST standard for smokers and non-smokers, firefighters demonstrated statistically significant differences in urinary concentration differences for the following metabolites: 2-OH-fluorene, 3-OH-fluorene and 1-OH-pyrene, which were lower in firefighters than the NIST mean for smokers. 1-OH-phenanthrene, 2-OH-phenanthrene and 3-OH-phenanthrene were higher among world trade center exposed firefighters than the NIST mean for smokers. When firefighters were compared to the NIST non-smoker standard, firefighters demonstrated elevated levels in all tested PAH biomarkers due to a mixture of smokers and non-smokers in the firefighter cohort. Asphalt workers had statistically significant higher urinary concentration elevations in 2-OH-fluorene, 1-OH-phenanthrene and 3-OH-phenanthrene as compared to the NIST smoker mean. When asphalt pavers were compared to the NIST non-smoker mean, asphalt pavers had statistically significant increases in all tested PAH biomarkers, with the exception of 2-OH-phenanthrene. While firefighters did not demonstrate a substantial change in urinary PAH metabolite levels compared to control populations of smokers and non-smokers, asphalt pavers experienced concentrations that were in some cases increased by orders of magnitude compared to NIST controls. Future research may be needed to evaluate any potential health risk posted to occupational exposed asphalt pavers.

Setenta e três fungos representantes de grupos taxonômicos distintos, isolados de cnidários, coletados no litoral norte do estado de São Paulo, foram submetidos ao teste de descoloração do corante RBBR e ao teste de MIC. Treze fungos selecionados no teste de descoloração foram submetidos ao teste de degradação de pireno e benzo[a]pireno. Sete fungos mostraram resultados satisfatórios de degradação, entretanto, o fungo Aspergillus sulphureus (8.2A) apresentou os melhores resultados: degradou 99,7% de pireno e 73,6% de benzo[a]pireno. Com relação ao teste de MIC, 21 isolados inibiram o crescimento das bactérias: B. subtillis; P. aeruginosa, S.aureus, E. coli EPEC e V. parahaemolyticus. Penicillium sp. (12.12) apresentou o melhor resultado (0,0078 mg/mL). Os 23 isolados que apresentaram potencial biotecnológico foram caracterizados taxonomicamente. Os resultados do presente trabalho sugerem que fungos filamentosos associados a cnidários possuem potencial para aplicação biotecnológica, em particular para biorremediação de ambientes marinhos contaminados com HPAs. / Seventy three fungi representatives of distinct taxonomic groups, isolated from cnidarians collected from north coast of São Paulo State, were submitted to RBBR dye decolorization tests and to MIC. Thirteen fungal selected from the decolorization test were submitted to pyrene and benzo[a]pyrene degradation assays. Seven fungi showed satisfactory PAH degradation results. Among them Aspergillus sulphureus (8.2A) presented the best results degrading pyrene (99.7%) and benzo[a]pyrene (73.6%). Regarding the MIC experiments, 21 isolates were able to inhibit the growth of B. subtilis, P. aeruginosa, S. aureus, E. coli EPEC and V. parahaemolyticus. Penicillium sp. (12.12) presented the best result (0,0078 mg/mL). The 23 isolates that showed potential biotechnologic were taxonomically characterized. Results derived from the present work suggest that cnidarians-derived filamentous fungi have a great potential for biotechnological application, in particular on bioremediation of marine environments contaminated by PAHs.

oundry production, which forms an integral part of the engineering industry, is a source of waste with a negative impact on the working and living environment. The pressure on greening the production in all production branches of industry does not dodge the foundry industry and technical engineers seek out possibilities of decreasing the negative impact of the production of casting on the environment. An important source of environmentally dangerous waste in foundry operation is the use of organic compounds during the preparation of shaping and core mixtures. Their substitution with materials that would ensure similar technological features of the shaping and core mixtures as the organic materials used hitherto and at the same time decrease the amount of solid, liquid and gaseous ecologically undesirable compounds used in or arising during the preparation and use of shaping and core mixtures, would be significant for decreasing the ecological burden connected to casting production. A promising group of materials usable as components of shaping and core mixtures are the biopolymer materials which can substitute the organic connective systems used in the production of foundry cores by the means of the so-called hot processes – Hot-Box and Warm-Box. This work focuses on the exploration of the technological and ecological features of several biopolymer materials available on the domestic market which have the potential to become a full alternative of the binders used so far on the basis of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and furan resins.

No description available.

Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are two atmospheric pollutants produced by motor vehicles using carbonaceous fuels. As a part of the Mexico City Project, measurements of BC, PPAHs and many other gas- and particle-phase emissions were measured in Mexico City using a mobile laboratory during the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003). The main goal of this research is to estimate emissions of BC and particulate PAHs (PPAHs) for Mexico City's vehicle fleet. The emissions of gas-phase pollutants such as carbon monoxide (CO), total nitrogen oxides (NOy) and volatile organic compounds (VOC) are also estimated. The mobile lab has previously been used to chase vehicles and measure their emissions, but analysis has traditionally focused on determining emission factors of individual vehicles associated with specific chasing events. The laboratory continuously samples ambient air from an inlet at the front of the van, and it is always "seeing" exhaust plumes from the vehicles around it while driving through traffic. We have developed an algorithm that automatically identifies the exhaust plume measurement points, which are then used as the basis for calculation of emission factors. In the nearly 90 hours of on-road sampling during the field campaign, we have identified ~30,000 exhaust measurement points. The large sample size enables us to estimate fleet-average emission factors and thus the emission inventory. Motor vehicles are estimated to emit annually 1,960 tons of BC, 56.2 tons of PPAHs, 1,320,000 tons of CO, 125,000 tons of NOy and 2440 tons of VOCs. The spatial and temporal patterns of BC and PPAHs in different locations with in MCMA are also studied. / Master of Science

Mit Hilfe der Rastertunnelmikroskopie (STM, Scanning Tunneling Microscopy) und Tunnelspektroskopie (STS, Scanning Tunneling Spectroscopy) wurden in situ das Ordnungsverhalten und die elektronischen Eigenschaften verschiedener alkylsubstituierter, polyzyklischer Aromaten (PAHs, Polycyclic Aromatic Hydrocarbons) an der Grenzfläche zwischen organischer Lösung und der Basalfläche von Graphit untersucht. Die Anzahl der pro Molekül vorhandenen pi-konjugierten Kohlenstoffatome reicht von 42 (Hexabenzocoronen, HBC) bis 114. Zusätzliche Informationen zur Struktur der geordneten Systeme lieferten kraftfeldbasierte Molekülsimulationen. Die molekularen Systeme bilden durch Adsorption und Selbstaggregation hochgeordnete Monolagen auf der Graphitoberfläche aus, wobei die polyzyklischen Kohlenstoffstrukturen der aromatischen Bereiche wie das darunter liegende Graphitgitter orientiert und die Molekülkristalle kommensurabel mit dem Substrat sind. Die peripheren Alkylketten sind nicht notwendigerweise an der Adsorption auf dem Graphitgitter beteiligt. Dies führt in bestimmten Fällen zu hexagonalen Anordnungen der HBC-Moleküle. Periodische Helligkeitsmodulationen im Tunnelbild der Aromaten werden über unterschiedliche Adsorptionspositionen auf dem Substrat erklärt, die in regelmäßiger Weise durch die molekularen Spezies eingenommen werden. In vielen Fällen ist die Adsorption nicht auf Monolagen begrenzt. Attraktive pi--pi-Wechselwirkungen zwischen den Aromaten werden als Ursache für die Stapelung der Moleküle angeführt. Es besteht die Vermutung, dass auch ein signifikanter Überlapp von Orbitalen vorhanden ist. Folglich wird der an der Grenzfläche zum Graphit existierende molekulare Ordnungszustand auf die zusätzlich adsorbierenden Schichten übertragen. Die Beobachtung nichtperiodischer Kontrastmodulationen wird auf kleinste Unterschiede in den Stapelweisen der Aromaten zurückgeführt, die zu Unterschieden in den elektronischen Eigenschaften führen. Hochaufgelöste STM-Bilder zeigen verschiedene Punktmuster und Streifen innerhalb der aromatischen Bereiche einzelner Moleküle. Diese Muster können nicht direkt der elektronischen Struktur der Aromaten zugeordnet werden. Sie werden vielmehr als Ergebnis einer Faltung der elektronischen Eigenschaften von Substrat und Adsorbat betrachtet. Zwei der Punktmuster, die für ein HBC-Derivat beobachtet wurden und abhängig von der Anzahl der pro Aromatenstapel involvierten Moleküle sind, konnten als sqrt(3) x sqrt(3) R 30°- bzw. als 2 x 2 -Überstruktur des Graphits beschrieben werden. Die STS-Experimente waren auf die Aufnahme lokaler I(U)-Kennlinien gerichtet. Die Aromaten weisen eine asymmetrische I(U)-Charakteristik auf, die Ähnlichkeiten mit dem Kennlinienverlauf einer Diode zeigt. Die Asymmetrie wird durch resonantes Tunneln über das HOMO bei negativen Probenspannungen erklärt. Die Verstärkung der Asymmetrie mit zunehmender Größe des Aromaten wird durch den kleiner werdenden energetischen Abstand zwischen HOMO und Fermi-Niveau des Graphits verursacht. / Self-assembled structures and electronic properties of alkylsubstituted, polycyclic aromatic hydrocarbons (PAHs) at the solid liquid interface between a solution and the basal plane of graphite have been studied in situ by scanning tunneling microscopy (STM) and spectroscopy (STS). The number of pi-conjugated carbon atoms per investigated molecular species ranges from 42 (hexabenzocoronene, HBC) to 114. Supplementary structural information was obtained by forcefield based simulations. Upon adsorption and self-assembly, the molecules form ordered monolayers on the graphite surface. Predominantely, the polycyclic carbon structures of the aromatic moieties exhibit the same orientation as the underlying graphite lattice and the molecular lattices are commensurate with the substrate. The peripheral alkyl chains do not necessarily adsorb on the substrate which leads to hexagonal packings of the HBCs in some cases. Periodic contrast modulations of the aromatic moieties in the STM images are attributed to different adsorption sites on the graphite lattice. These different positions are occupied by the molecules in a regular way. In many cases, the adsorption is not limited to monolayers. It is proposed that the stacking is governed by pi--pi-interactions between the aromatic regions including a significant overlap of orbitals. As a consequence, the molecular order from the solid liquid interface is transferred to the additionally adsorbing layers. Nonperiodic contrast modulations indicate slight differences in the stacking giving rise to modified electronic properties. Highly resolved STM images show different dot patterns and stripes within the aromatic region of single molecules. These patterns do not directly stem from the electronic structure of the aromatic species. Instead, they are rather explained by a convolution of the electronic properties of both, substrate and adsorbate. Two of the dot patterns observed for an HBC derivative could be described as sqrt(3) x sqrt(3) R 30°- and as 2 x 2 -superstructure of the graphite lattice, respectively, depending on the number of stacked molecules. STS involved the measurement of I(U)-curves at specific locations. The curves of the aromatic moieties exhibit an asymmetric, diode like behavior explained by resonant tunneling via the HOMO at negative substrate voltages. The asymmetry is enhanced with increasing size of the aromatic moiety. This is due to the reduced distance between the HOMO and the graphite Fermi level for the larger PAHs.

If sufficiently persistent, semi-volatile organic contaminants (SVOCs) can travel long distances through the atmosphere from their points of release and become concentrated in cold, remote regions. As air is sampled for SVOCs to establish both their presence and the success of emission reduction efforts, it becomes helpful to determine sampling site proximity to sources and the origin of the sampled air masses. Comparing three increasingly sophisticated methods for quantifying source proximity of sampling locations, it was judged necessary to account for the actual history of the sampled air through construction of an airshed, especially if wind is highly directional and population distribution is very non-uniform. The airshed concept was improved upon by introducing a ‘geodesic’ grid of equally spaced cells, rather than a simple latitude/longitude grid, to avoid distortion near Earth’s poles and to allow for the comparison of airshed shapes. Assuming that a perfectly round airshed reveals no information about sources allows the significance of each cell of an airshed to be judged based on its departure from roundness. Combining air-mass histories with a 2 year-long series of SVOC air concentrations at Little Fox Lake in Canada’s Yukon Territory did not identify distinct source regions for most analytes, although γ-hexachlorocyclohexane appears to originate broadly in north-eastern Russia and/or Alaska. Based on this remoteness from sources, the site is judged to be well suited to monitor changes in the hemispheric background concentrations of SVOCs. A model-based exploration revealed wet-gaseous deposition as the dominant process responsible for cold-trapping SVOCs in mountain soils. Such cold trapping is particularly effective if precipitation rate increases with altitude and if temperature differences along the mountain are large. Considerable sensitivity of the modeled extent of cold-trapping to parameters as diverse as scale, mean temperature, atmospheric particle concentration and time relative to emission maxima is consistent with the wide variety of observed enrichment behaviour. Concentration gradients of polycyclic aromatic hydrocarbons and polychlorinated biphenyls in air and soil measured on four Western Canadian mountains with variable distance from sources revealed source proximity as the main driver of concentrations at both the whole-mountain scale and along individual mountain transects.

If sufficiently persistent, semi-volatile organic contaminants (SVOCs) can travel long distances through the atmosphere from their points of release and become concentrated in cold, remote regions. As air is sampled for SVOCs to establish both their presence and the success of emission reduction efforts, it becomes helpful to determine sampling site proximity to sources and the origin of the sampled air masses. Comparing three increasingly sophisticated methods for quantifying source proximity of sampling locations, it was judged necessary to account for the actual history of the sampled air through construction of an airshed, especially if wind is highly directional and population distribution is very non-uniform. The airshed concept was improved upon by introducing a ‘geodesic’ grid of equally spaced cells, rather than a simple latitude/longitude grid, to avoid distortion near Earth’s poles and to allow for the comparison of airshed shapes. Assuming that a perfectly round airshed reveals no information about sources allows the significance of each cell of an airshed to be judged based on its departure from roundness. Combining air-mass histories with a 2 year-long series of SVOC air concentrations at Little Fox Lake in Canada’s Yukon Territory did not identify distinct source regions for most analytes, although γ-hexachlorocyclohexane appears to originate broadly in north-eastern Russia and/or Alaska. Based on this remoteness from sources, the site is judged to be well suited to monitor changes in the hemispheric background concentrations of SVOCs. A model-based exploration revealed wet-gaseous deposition as the dominant process responsible for cold-trapping SVOCs in mountain soils. Such cold trapping is particularly effective if precipitation rate increases with altitude and if temperature differences along the mountain are large. Considerable sensitivity of the modeled extent of cold-trapping to parameters as diverse as scale, mean temperature, atmospheric particle concentration and time relative to emission maxima is consistent with the wide variety of observed enrichment behaviour. Concentration gradients of polycyclic aromatic hydrocarbons and polychlorinated biphenyls in air and soil measured on four Western Canadian mountains with variable distance from sources revealed source proximity as the main driver of concentrations at both the whole-mountain scale and along individual mountain transects.