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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.
1

Análise da biodiversidade microbiana em ambiente aquático com despejo contínuo de efluentes de hidrocarbonetos

Ruiz, Marelis Margarita 02 February 2014 (has links)
Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-07-09T14:19:32Z No. of bitstreams: 1 Tese - Marelis Margarita Ruiz.pdf: 48193021 bytes, checksum: 4e7e0fa3715216dbc1c8be5df2d8a197 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-09T14:27:06Z (GMT) No. of bitstreams: 1 Tese - Marelis Margarita Ruiz.pdf: 48193021 bytes, checksum: 4e7e0fa3715216dbc1c8be5df2d8a197 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-09T14:30:24Z (GMT) No. of bitstreams: 1 Tese - Marelis Margarita Ruiz.pdf: 48193021 bytes, checksum: 4e7e0fa3715216dbc1c8be5df2d8a197 (MD5) / Made available in DSpace on 2015-07-09T14:30:24Z (GMT). No. of bitstreams: 1 Tese - Marelis Margarita Ruiz.pdf: 48193021 bytes, checksum: 4e7e0fa3715216dbc1c8be5df2d8a197 (MD5) Previous issue date: 2014-02-02 / Não Informada / In the Amazon region, the Urucu Oil Province (Petrobras) has been disposing of hydrocarbon effluents into the surrounding aquatic environments since the beginning of its operations. The goal of this work was to analyze the bacterial biodiversity present in the dike of the effluents and in the stream before and after the disposal of hydrocarbon effluents. A study was conducted in two stages were carried out with the use of culture independent molecular techniques. The full genomic DNA of the sediment and water samples were extracted and used as templates in a PCR reaction with the use of specific oligonucleotides of the 16S rRNA gene bacteria domain. The PCR product was amplified and pyrosequenced, and the generated sequences were analyzed by the free software Mothur. The measurements of the physical-chemical and chromatographical parameters are within the measures established for these types of analyzed water bodies. In the first stage of the study, the taxonomic profiles of the samples have shown that the Proteobacteria phylum proved to be the most abundant together with the Deltaproteobacteria class and the gen known as Candidatus Solibacter. Similarly, in the second stage of the study, the Proteobacteria phylum proved to be the most abundant together with the Alphaproteobacteria class and the Geobacter gen predominant. Both genes are catalogued as bioremediators in contaminated environments, as well as 14% of the total genes. A large proportion of microorganisms were considered “Unclassified” (up to 30%). In first stage of the study the richness and the diversity of species in the Onça stream is greater following the disposal of hydrocarbon effluents, in second stage of the study the abundance and diversity of species in the natural stream (without a name in the region), is greater as compared to the same stream after the mixing of effluents. There is no significant statistical difference between the sample of the community in the natural stream and this effluent-mixed stream; and there is no difference in genetic structure among samples of each community analyzed, suggesting that the discharge of effluents in this body of water has no significant impact on the microbial biodiversity in this aquatic environment. This work, a pioneer in the taxonomic analysis of samples in dikes of effluents and streams with the disposal of effluents in the Urucu oil area, represents a challenge for understanding the relationship between the composition, abundance and diversity of microorganisms in this environment, and a rich source for the discovery of new taxonomic groups, as well as the huge potential for biotechnological exploration of such diversity. / Na região Amazônica, a Província Petrolífera de Urucu (Petrobras) realiza o despejo de efluentes de hidrocarbonetos em ambientes aquáticos ao redor, desde o início de suas operações. O objetivo deste trabalho foi analisar a biodiversidade bacteriana presente no dique de efluentes e no igarapé antes e depois do despejo de efluentes. Foi realizado um estudo em duas etapas, aplicando técnicas moleculares independentes de cultivo. O DNA genômico total das amostras de sedimento e água foi extraído e usado como molde em uma reação de PCR utilizando oligonucleotídeos específicos do gene 16S rRNA para o domínio Bactéria. O produto de PCR foi amplificado e pirosequenciado, e as sequências geradas foram analisadas pelo programa livre Mothur. As medidas dos parâmetros físico-químicos e cromatográficos estão dentro dos valores estabelecidos para os tipos de corpos de água analisados. Na primeira etapa do estudo, os perfis taxonômicos das amostras mostraram que o filo Proteobacteria foi o mais abundante com a classe Deltaproteobacteria e gênero conhecido o Candidatus Solibacter. Assim mesmo, na segunda etapa do estudo, o filo Proteobacteria foi o mais abundante; porém, com a classe Alphaproteobacteria e o gênero Geobacter como predominante. Ambos gêneros são catalogados como biorremediadores de ambientes contaminados, assim como 14% dos gêneros totais. Uma grande parte de microrganismos foram considerados “Não Classificados” (até 30%). Na primeira etapa do estudo a riqueza e diversidade de espécies no Igarapé da Onça, é maior depois do despejo de efluentes de hidrocarboneto, e na segunda etapa do estudo a riqueza e diversidade de espécies no igarapé natural (sem nome na região), é maior com relação a este mesmo igarapé depois da mistura com efluentes. Não existe diferença estatística significativa entre a comunidade do igarapé natural e entre este igarapé misturado com efluentes; e não existe diferença na estrutura genética entre as amostras de cada comunidade analisada, indicando que a descarga de efluentes neste corpo de água não tem impacto significativo na biodiversidade microbiana deste ambiente aquático. Este trabalho, pioneiro em análise taxonômica de amostras de um dique de efluentes e os igarapés com despejo de efluentes na área petrolífera de Urucu, representa uma oportunidade para a compreensão da relação entre a composição, abundância e diversidade dos microrganismos neste ambiente, e uma fonte rica para descoberta de novos grupos taxonômicos, assim como um enorme potencial para exploração biotecnológica desta diversidade.
2

La nature juridique des titres miniers dans les états de l’OHADA / The legal nature of mining title in the states parties of OHBLA

Mbodji, Mohamadou Fallou 13 April 2018 (has links)
Dans les législations nationales des états membres de l’OHADA, les ressources minières et pétrolières relèvent de la souveraineté et de la propriété des états. Cette appropriation publique des ressources naturelles a largement influencé la conception des titres miniers qui reposent ainsi sur un encadrement administratif. Leur nature juridique aurait dû alors suivre celle des actes de l’administration et embrasser toutes les dispositions relevant de la catégorie des actes administratifs unilatéraux. Toutefois, si les titres miniers sont intimement liés à l’état d’accueil, leur nature juridique ne saurait être réduite à celle d’actes administratifs, ceux-ci n’étant qu’un instrument de gestion du secteur extractif. L’analyse des législations nationales révèle que les titres miniers sont légalement consacrés comme des biens. Cependant, contrairement à ce qu'affirment les législations nationales, ils ne sont ni des biens meubles, ni des biens immeubles. En effet, les titres miniers constituent des droits d’accès, c'est-à-dire des droits de procéder aux opérations minières et pétrolières, de durée limitée, distincts de la propriété des gisements. De tels droits constituent des biens purement incorporels jouissant d'un régime de protection juridique inhérent à leur qualité de biens. Ces biens incorporels revêtent une valeur économique qui leur permet d'accéder au commerce juridique. Ils peuvent faire l’objet d’un transfert de propriété par cession, amodiation ou transmission. Ils peuvent également servir de financement pour les activités de recherche et d’exploitation en constituant l’assiette de sûretés minières comme l’hypothèque et le nantissement / In the national legislation of member’s states of OHBLA, mining and oil resources are the sovereignty and ownership of the state. This public ownership of naturel resources largely influenced the design of the mining titles which are based on administrative guidance. Their legal nature should have then followed that acts of administration and kiss all the provisions falling under the category of unilateral administrative acts. However, if the claims are closely related to the host states, their legal nature cannot be reduced to that of administrative acts, these being only an instrument of the extractive sector management. Indeed, the claim are access right, i.e. rights to conduct the mining and oil. They are limited in time and distinct form ownership of the deposit. Analysis of national legislation shows that they are legally dedicated as goods. This new category of goods are representative of property titles. Indeed, in the national legislation of the states of OHBLA, the mining titles are apprehended as objects of trade. They offer their holders all the prerogative of ownership. Like other goods of common law, they are asset, which can move from one contractor to another by directly the object of trade like transfer, leasing or transmission. They can also serve as financing for activities of research and exploitation constituting mining securities such as mortgage and pledge. It should be noted, however, that these types of guarantees do not really correspond to the true legal nature of mining titles. For in accordance with the classification established by the uniform act on the law of security interest, mining titles should only be pledged
3

Evaluation de l'exposition humaine liée aux activités pétrolières en Equateur : de la surveillance de la qualité de l'air à l'étude du transfert des contaminants métalliques dans le continuum sol-plante / Human exposure assessment related to oil activities in Ecuador : from the air quality monitoring to the study of metallic contaminants transfer in the soil-plant continuum

Barraza Castelo, Fiorella 13 October 2017 (has links)
L'Équateur est le 5ème pays producteur de pétrole en Amérique du Sud. Les étapes d'extraction et de raffinage génèrent des déchets contentant des métaux co-émis avec les hydrocarbures aromatiques polycycliques (HAPs), connus pour leurs effets cancérogènes et toxiques chez l'homme. Dans ce contexte et dans le cadre du programme ANR MONOIL, le premier objectif de cette thèse était de déterminer la distribution des métaux dans l'environnement sur les provinces d'Orellana et Sucumbíos (zones d'extraction du pétrole en Amazonie, " NAR ") et dans la ville d'Esmeraldas (raffinerie, sur la côte Pacifique," NPC "). Le 2ème objectif était d'étudier le transfert des métaux depuis le sol ou l'air vers les cacaoyers, largement cultivés en Equateur, et d'en déterminer les impacts sur la santé après ingestion. Enfin, le 3ème objectif était de surveiller la qualité de l'air (PM10) afin d'évaluer l'impact des activités anthropiques et le potentiel oxydatif des particules. Des sols et des cultures ont été collectés dans 31 fermes entre 2014 et 2016. Des échantillons d'air ont été prélevés mensuellement sur 3 sites, à proximité des plateformes pétrolières et de la raffinerie. La composition chimique (teneurs en métaux, carbone organique et élémentaire, ions, sucres, polyols, HAPs) a été déterminée dans les PM10. L'évaluation des risques sanitaires a été réalisée via 3 voies d'exposition. Les effets non cancérogènes et cancérogènes ont été quantifiés à l'aide de l'Indice de Risque (HI) et du Risque Total de Cancer (TCR). La bioaccessibilité du Cd par ingestion a été déterminée avec le test BARGE dans les pâtes et fèves de cacao. La formation d'espèces réactives de l'oxygène (ROS) a été quantifiée par spectrophotométrie en utilisant 3 essais acellulaires: DTT, AA et DCFH. Les résultats montrent que dans 72% des sites, les concentrations en Ba, Co, Cu, Cr, Ni, V et Zn dans les sols dépassent les limites de la législation équatorienne. Pour la plupart des cultures, les concentrations en métaux sont inférieures aux limites de détection, sauf pour le Cd dans le cacao et le Pb dans le manioc, qui dérogent aux normes de qualité alimentaire. Les cacaoyers accumulent le Cd dans les feuilles, les cabosses et les fèves. Comme la teneur en Cd du pétrole est inférieure à la limite de détection, les produits agrochimiques et les intrants organiques peuvent être incriminés. Près de 100% de la teneur totale en Cd dans les pâtes et fèves de cacao est bioaccessible par ingestion. Le risque pour la santé après consommation de chocolat oscille entre faible et élevé, selon la quantité ingérée. Dans les PM10, le Ba et le Mo, traceurs spécifiques des activités pétrolières, ont montré des valeurs beaucoup plus élevées que celles enregistrées dans les sites industriels. Les ratios OC/EC étaient plus élevés en Amazonie, suggérant des émissions biogéniques plus importantes. La teneur en HAPs est plus élevée sur la côte, cependant les niveaux de BaP étaient inférieurs aux limites de l'UE. Les résultats du potentiel oxydatif ont montré que les composés émis par l'industrie pétrolière (HAPs, Ba, Ni, Zn), par la combustion de la biomasse (sucres) dans le NAR ainsi que les traceurs industriels dans le NPC (As, Ba, Ni, NH4+) corrèlent avec la génération de ROS. Les principales voies d'exposition aux métaux sont l'ingestion et l'inhalation et, dans une moindre mesure, le contact dermique avec le sol. Les enfants tout comme les adultes sont vulnérables aux effets toxiques de ces composés. Enfin, d'autres facteurs comme la déforestation, l'agriculture et les émissions naturelles (volcans) dans le NAR mais aussi les industries dans le NPC contribuent également aux dégâts environnementaux constatés et aux effets néfastes sur la santé. / Ecuador is the 5th crude oil producer country in South America. Oil extraction and refining generate toxic waste containing metals co-emitted with polycyclic aromatic hydrocarbons (PAHs), naturally present in crude oil or added during production, and known for their carcinogenic and toxic effects in humans. In this context and as a part of the ANR MONOIL program, the first aim of this PhD research was to determine the distribution of metal(loid)s in the environment in the provinces of Orellana and Sucumbíos (oil extraction, North Amazon " NAR ") and the city of Esmeraldas (oil refining, North Pacific Coast, " NPC "). The second aim was to determine if there was a transfer of toxic metals, such as Cd, from soil or air to cacao crops, widely cultivated in Ecuador, and if the consumption of cacao-based products could imply risks for human health. Finally, the third aim was to monitor air quality over 2 years in both areas to assess the impact of anthropogenic activities and the oxidative burden of particulate matter (PM10). Soils and local crops were collected in 31 small-scale farms, between 2014 and 2016. Monthly PM10 samples were collected in 3 sites, in the vicinity of oil platforms close to the refinery. PM10 chemical composition (contents in metals, organic and elementary carbon (OC, EC), ions, sugars, polyols, PAHs) was determined. Human health risk assessment was performed taking into account ingestion, inhalation and dermal contact. Non carcinogenic and carcinogenic effects were quantified using the Hazard Index (HI) and the Total Cancer Risk (TCR). Bioaccessibility of Cd after ingestion was determined by the BARGE in vitro test in cacao beans and liquors. In aerosols, reactive oxygen species (ROS) formation was quantified using 3 acellular assays: DTT (dithiothreitol), AA (ascorbic acid) and DCFH (2',7'-dichlorodihydrofluorescein). Ba, Co, Cu, Cr, Ni, V and Zn concentrations in 72% of the study soils exceeded the limits of the Ecuadorian legislation. For most of the crops, elements were below the limits of detection but, Cd in cacao and Pb in manioc were above the international standards for food quality. Cacao trees accumulate Cd in leaves, pod husks and beans. Because Cd contents in crude oil were below the detection limits, agrochemical products and natural inputs may also be important sources. Almost 100% of the total Cd content in cacao beans and liquor was bioaccessible by ingestion. The health risk after chocolate consumption was low to high, depending on the ingestion rate and the cacao liquor percentage. In PM10, As, Cd, Ni and Pb were below the EU thresholds. However, Ba and Mo, specific tracers of oil activities, used as weighting agents or catalyzers during drilling and refining, showed values much higher than those recorded in other urban-industrialized sites. PM10 composition depended on oil activity. OC/EC ratios were higher in the NAR (oil extraction) than in the NPC (oil refining), suggesting that biogenic emissions were more important in the Amazon area. PAHs contents were higher in the NPC, but levels of benzo-a-pyrene were below the EU limits. Oxidative potential results showed that compounds emitted by oil industry (PAHs, Ba, Ni, Zn) and by biomass burning (sugars) in the NAR as well as industrial tracers in the NPC (As, Ba, Ni, NH4+) were correlated with ROS generation. Regarding residential exposure, the main routes of exposure to metal(loid)s were first ingestion, inhalation and in a small extent soil dermal contact, being both children and adults vulnerable. Finally, the oil Ecuadorian environment is not only contaminated by oil activities. Other factors like deforestation, agriculture and natural emissions (volcanos) in the NAR and industries in the NPC also contribute to environmental damages and may lead to adverse health effects.

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