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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.
121

Development and application of a proteomic approach to the assessment of pollution in the marine environment

Apraiz Larrucea, Itxaso January 2009 (has links)
Today, assessment of the health of coastal waters is recognized as being important for both the conservation of nature and well-being of humans. Anthropogenic pollution has been the focus of extensive research for some time and a variety of programs for the monitoring and assessment of environmental pollution have been developed. Determination of the levels of pollution in sensitive ‘sentinels’ such as mussels, allows monitoring of these levels in a given area over a prolonged period of time. Furthermore, the biological effects of pollution are reflected in a series of biomarkers, none of which provides a general picture of the sentinel’s state of health and all of which are individually specific for certain pollutants and influenced by both biotic and abiotic factors. In an attempt to improve biomonitoring of marine pollution, we have developed two proteomic approaches here. In the first portion of the thesis, a proteomic analysis was performed on peroxisomes isolated from mussels exposed either to one of three model anthropogenic pollutants, or two different types of crude oil, or from mussels exposed to the Prestige oil spill. Application of two-dimensional electrophoresis (2-DE) provided protein expression signatures (PES) for exposure to these different pollutants.Furthermore, several individual protein components of these PES could be putatively identified. In the second portion of this work, such analysis of subproteomes was developed further in order to improve the applicability of this approach to biomonitoring. A simple fractionation procedure in combination with liquid chromatography and 2-DE provided samples from mussels residing in different regions of a pollution gradient around the harbor of Gothenburg, as well as from mussels exposed to two types of fuel oil similar to that of the Prestige that were suitable for environmental proteomics. In addition, we constructed a model for this approach that can be cross-validated in the future and applied to assess sources of fuel oil pollution in connection with biomonitoring programs.
122

Exploitation offshore d'hydrocarbures et responsabilité civile : droit comparé : Brésil, France et Etats-Unis / Offshore oil exploitation and civil liability : comparative Law : Brazil, France and United States

Vianna Goncalves, Raphael 10 November 2015 (has links)
La situation actuelle des règles relatives à la responsabilité civile de l'entrepreneur pour les dommages environnementaux provoqués par l’exploitation offshore d’hydrocarbure et le transport de ce produit par des navires pétroliers, démontre que le législateur a été de plus en plus concerné par la question de la santé environnementale. Cependant, il y a beaucoup de lacunes dans les lois nationales qui peuvent entraîner une incertitude juridique considérable pour l'entrepreneur et en même temps, ne pas fournir une protection adéquate à l'environnement et à l’homme. L’étude comparée des systèmes juridiques démontre qu’il est extrêmement important que les pays qui sont exposés aux périls des marées noires, notamment ceux qui exploitent des hydrocarbures dans la mer, disposent d’un fonds spécial d’indemnisation pour garantir et faciliter la restauration de l’environnement et le payement des indemnisations aux victimes. Outre la protection de l’environnement et des droits des citoyens, le fonds offre aussi la possibilité d’application des cas exceptés et de la limitation de responsabilité. Le fonds serait utilisé pour couvrir les préjudices au-delà de la limite de responsabilité de l’entrepreneur ou dans les cas où la responsabilité de celui-ci est écartée par un cas excepté. / The current situation of the rules governing the liability of the entrepreneur for environmental damage caused by offshore oil exploration and by the transportation of this product by oil tankers, shows that the legislator is more concerned with environmental health issues. However, there are many gaps in national legislations that can lead to considerable legal uncertainty for the responsible parties. While, at the same time it does not provide adequate protection for the environment and to human beings. The comparative study of legals systems shows the importance that countries that are exposed to the dangers of oil spills, especially those exploiting oil in the sea, to have a special indemnisation fund to guarantee and facilitate environmental restoration and payment of compensation to victims. Besides protecting the environment and citizens' rights, the fund also offers the possibility of applying the defenses of liability and limitation of liability. The funds would be used to cover the losses beyond the limit of liability of the responsible partie or when the responsibility for the accident is ruled out by a liability defense cause.
123

L’exploration-production offshore des hydrocarbures : prévention, répression et réparation des déversements illicites d’hydrocarbures / Offshore oil exploration-production : Prevention, repression and remedies of oil spill

Tuelle-Pambo, Imelda 01 December 2016 (has links)
Dans l’attente d’une augmentation de la part des énergies renouvelables dans le mix énergétique, les énergies fossiles, telles que les hydrocarbures, restent encore la première source d’approvisionnement énergétique de l’Homme. La raréfaction des hydrocarbures sur le continent conduit les industriels à se tourner vers l’offshore. Ainsi, aux Etats-Unis (1er pays producteur de pétrole au monde en 2015), la production pétrolière offshore (principalement concentrée dans le Golfe du Mexique) représente plus de la moitié de la production nationale totale de pétrole. La France, quant à elle, se tourne désormais vers l’exploration de sa très grande zone offshore s’étendant sur les quatre coins du monde (notamment au large des côtes guyanaises). Une telle importance économique ne doit pas passer sous silence la dangerosité de l’exploitation pétrolière offshore. L’explosion du Deepwater Horizon en avril 2010, au large des côtes de la Louisiane (Golfe du Mexique ; Etats-Unis) en est une parfaite illustration (11 salariés tués, endommagement de l’écosystème, victimes collatérales, etc.). Le droit doit pouvoir appréhender efficacement les risques générés par l’exploitation des hydrocarbures en offshore. L’étude comparative des législations française et états-unienne met en exergue les carences du droit français. L’exploitation des ressources minérales du plateau continental des Etats-Unis, la répression des déversements illicites d’hydrocarbures et, la réparation des dommages qui en résultent, sont régies par des lois fédérales spéciales. A contrario, l’exploitation du plateau continental et de la Zone économique exclusive française s’inscrit dans un cadre législatif et règlementaire plus général. Il apparaît donc nécessaire de proposer une réforme de la législation actuelle. Dans cette optique, ce travail a vocation à émettre des propositions de réforme. La nouvelle législation française spéciale doit être pensée dans une approche systémique. Les éléments qui composent le système doivent interagir. Le premier élément est un régime optimal de prévention qui, s’articule autour de la sécurité des travailleurs et des installations. Le second élément est un régime de répression des infractions à la législation de prévention et, du délit de pollution par les hydrocarbures. Le troisième élément est un régime d’indemnisation civile de plein droit des conséquences dommageables de l’accident pétrolier (lorsqu’il n’est pas couvert par le régime exclusif d’indemnisation des accidents du travail) et du déversement d’hydrocarbures. Responsabilités pénale et civile concourent par ailleurs à la prévention par la dissuasion, cela en vue d’une meilleure internalisation des risques dans la politique managériale des entreprises pétrolières et parapétrolières intervenant sur les sites. / Waiting for a complete change to the development of renewable energies, fossil energies, such as conventional oil and gas, remain still the primary source of energy supply. The rarefaction of conventional oil on the continent has lead major oil companies to turn to the offshore. Thus, in the United States (First oil producer country in the world in 2015) the offshore oil exploitation (mainly concentrated in the Gulf of Mexico) represents more than half of the national oil production. France, as for it, turns now to the exploration of its very great offshore zone extending on the four world’s corners (particularly, off the Guyana’s coasts). This significant economic development should not overlook the dangerousness of offshore oil activities. The explosion of Deepwater Horizon in April 2010, off the Louisiana’s coasts (Gulf of Mexico, The United States) is a perfect illustration (11 killed employees, ecosystem damaged, collateral victims, etc). The Law must be able to frame the risks generated by the offshore oil activities. The comparative study of French and American legal systems highlights French law’s gaps. The exploitation of the American continental shelf’s mineral resources, the repression of unlawful oil discharges and, the remedies of damages, which result from it, are governed by special federal laws. A contrario, the exploitation of the French continental shelf and exclusive economic Zone is governed by general laws. It thus appears necessary to promote a reform of the current legislation. Accordingly, this work is to put forth reform proposals. The special French new legislation must be worked out in a systemic approach. The elements which compose the system must interact. The first element is an optimal prevention that is articulated around the security of the workers and the installations. The second element is the repression of the offenses to the legislation of prevention and, unlawful oil discharges. The third element is a strict liability for the damages result from oil accident (when they are not covered by the exclusive liability for the damages result from occupational accidents) and oil spill. Criminal and civil liabilities also contribute to the prevention by the deterrent for better consideration of risks in the management of oil companies and others companies involving in offshore oil activities.
124

Undocumented oil leakages : A study about stern tube seals and leakages / Odokumenterade oljeläcklage : En studie om propellerhylstätningar och läckage

Lundberg, Johan January 2021 (has links)
The majority of the vessels in the commercial fleet utilize oil lubricated stern tubes. Unfortunately, this brings about a risk of oil leaking from the stern tube into the marine environment if the stern tube seal would become worn or damaged by foreign materials. Previous studies concluded that, on average, 2.6 litres of oil per day leak out from the stern tube of ships. This essay has investigated the causes that could increase the leakage rate from the stern tube by reviewing literature, interviewing experts, and sending out surveys with questions regarding the subject. The answers that were received painted a clear picture that it is impossible to get a perfect seal on a stern tube. The causes that could influence the leakage rate were design related, such as vibrations, the rotational speed of the propeller shaft, radial and axial movements of the propeller shaft, as well as external causes such as the quality of water and foreign materials, for example, fishing lines and nets. The question whether water lubricated stern tubes were a viable alternative compared to oil lubricated stern tubes was also investigated. The result was that the bearing on a water lubricated stern tube did not have as long lifespan as an oil lubricated bearing. / Majoriteten av fartygen i handelsflottan använder oljesmorda propellerhylsor för att smörja propelleraxeln. Tyvärr medför det en risk att olja kan läcka ut från hylsan om tätningarna skulle bli utslitna eller skadas av främmande föremål. Tidigare forskning har visat att cirka 2,6 liter olja per dag läcker ut genomsnittligen från fartyg i handelsflottan. Denna uppsats har utrett vad som kan påverka läckagemängden från en propellerhylsa genom att utnyttja intervjuer och enkätsvar. Svaren som framkom var att det är mer eller mindre omöjligt att få en perfekt tätning på en propellerhylsa. Saker som kan påverka läckagemängden var designfenomen som vibrationer, axiella- och radiella rörelser och varvtal på propelleraxeln, samt yttre påverkan som vattenkvalité och främmande föremål som fiskelinor och nät. I uppsatsen jämförs även vattensmorda propellerhylsor med fokus på livstid, kostnad och underhåll, med en oljesmord propellerhylsa. En slutsats är att det vattensmorda lagret inte har samma livstid som det oljesmorda.
125

Modélisation et mesure de l’interaction d’une onde électromagnétique avec une surface océanique. Application à la détection et à la caractérisation radar de films d’hydrocarbures. / Electromagnetic Wave Scattering Modeling and Measurement from Ocean Surfaces. Detection and Characterization of an Oil Film.

Mainvis, Aymeric 05 December 2018 (has links)
Les instruments, satellites ou systèmes aéroportés, actuellement utilisés pour la détection et la caractérisation d'hydrocarbure sur la mer sont basés sur des moyens optiques ou radars. Ces moyens présentent une performance dégradée due à une fréquence encore trop importante de fausses alarmes ou à un temps de traitement des données trop conséquent. Les méthodes de détection, d'identification et de quantification des fuites d'hydrocarbures offshores peuvent donc être améliorées en associant robustesse et réactivité. Cette amélioration suppose une compréhension approfondie des phénomènes océanographiques et électromagnétiques à l'œuvre dans cette scène particulière. La thèse s'appuie sur des données regroupant des images optiques et SAR aéroportées ou satellites ainsi que des mesures réalisées en laboratoire. Ce jeu de données permet de vérifier la cohérence des résultats obtenus par modélisation. L'objectif de la thèse est de distinguer une surface de mer polluée d'une surface de mer propre à l'aide de la signature électromagnétique de la surface totale puis de détailler le type et la quantité d'hydrocarbure présent. La thèse se divise en deux domaines, à savoir modélisation océanographique et modélisation électromagnétique. La modélisation océanographique intègre la simulation de la surface rugueuse imitant une surface de mer propre, et polluée. Cette surface de mer doit être générée sur une superficie importante et doit conserver une résolution restituant les petites vagues avec un temps de génération minimal. La partie électromagnétique est centrée sur les modèles asymptotiques de diffusion des ondes électromagnétiques par une interface rugueuse. Ces modèles sont adaptés au contexte de la thèse, complexité de la scène et rapidité du traitement, mais nécessitent plusieurs hypothèses pour être appliqués. / Satellites or airborne systems currently used for the detection and characterization of oil slicks on sea surface are based on optical or radar means. These means have a lack of performance due to a too high frequency of false alarms or to an excessively long data processing time. The methods for detecting, identifying and quantifying offshore pollutant can therefore be improved by combining robustness and reactivity. This improvement implies an in-depth understanding of the oceanographic and electromagnetic phenomena at work in this particular scene. The thesis is based on data gathering aerial and satellite images and SAR as well as measurements carried out in laboratory. This dataset makes it possible to check the consistency of the results obtained by modeling. The objective of the thesis is to distinguish a polluted sea surface from a clean sea surface using the electromagnetic signature of the total surface and then to detail the type and quantity of pollutant. The thesis is divided into two domains, namely oceanographic modeling and electromagnetic modeling. Oceanographic modeling integrates the simulation of the rough surface imitating a clean or polluted sea surface. This sea surface must be generated over a large area with a thin resolution. The electromagnetic part is centered on the asymptotic models for the electromagnetic waves diffraction by a rough interface. These models are adapted to the context of the thesis, the complexity of the scene and the speed of processing, but require several hypotheses to be applied.
126

Genre criticism : an application of BP's image restoration campaign to the crisis communication genre

Eastlick, Anne C. 01 January 2011 (has links)
Within two months of its emergence, the BP Gulf Oil spill had become the worst environmental disaster in United States history. However, for those studying public relations the oil spill brought more than ecological disaster, by providing a case study of crisis communication. Although there were a number of crisis responses from BP throughout the course of the oil spill, the primary crisis response crafted by BP was an image restoration campaign which premiered in early June 2010. This campaign, though it exhibits qualities of a standard crisis response, was wildly unpopular with the United States Government and citizenry. This rhetorical analysis attempts to uncover the reasons behind the campaign's failure through an application of the genre model of criticism. By defining the crisis communication genre and applying it to the artifact, the current study uncovers the reasons behind the failure of the campaign. Through this discussion, this analysis identifies that BP did not address all necessary exigencies, nor did it consider the influence a rhetor can have on a message. An explanation for the failure of BP' s campaign provided a plethora of implications to the fields of public . relations and rhetorical criticism, while beginning a discussion to help define the crisis communication genre.
127

The fate and distribution of subsurface hydrocarbons released during the 2010 MC252 oil spill in deep offshore waters of the Gulf of Mexico

Spier, Chelsea L. 01 January 2012 (has links)
The explosion of the Deepwater Horizon oil platform on April 20, 2010 resulted in the second largest oil spill in history. In this study, the distribution and chemical composition of hydrocarbons within a 45 km radius of the blowout was investigated. A complete set of hydrocarbon data were acquired from the National Oceanic and Atmospheric Administration (NOAA) and from BP, including data from 16 research missions collected over eight weeks. The distribution of hydrocarbons was found to be more dispersed over a wider area in subsurface waters than previously predicted or reported. Several hydrocarbon plumes were identified including a near-surface plume (0.5 to 50 m), two small mid-depth plume (240 to 290 m and 850 to 880 m), and a large deepwater plume approximately 1,050 to 1,300 m below surface. Water soluble compounds were preferentially extracted from the rising oil in deepwater, and were found at potentially toxic levels both in and outside of areas previously reported to contain the majority of hydrocarbons. Data collected from different research missions were measured for a wide variety of chemical compounds, but not every sample was analyzed for the same chemical compounds. To overcome the challenge of variability in sample data, a non-parametric method of evaluating the percentage of detectable results, was used for all data analysis in addition to evaluation of total sample concentrations. The two analysis techniques yielded similar results. This approach may be useful in other studies in which samples are measured for varying number of compounds and have varying detection limits. The distribution and toxicity of hydrocarbons in sediments between August and October, 2010 was also investigated and was found to be fairly localized.
128

Comparing Media Coverage Of The Gulf Oil Spill In The Us And Uk Implications For Global Crisis Communication

Crytzer, Sarah 01 January 2011 (has links)
The following research is a content analysis of 114 articles written by the American and British news media outlets in the first month following the BP Gulf oil spill in April 2010. The goal of the research was to identify any dominant frames evident in the reports and to compare the two countries to see if there was a difference in the dominant frames used. Positive, negative, and neutral tones were also evaluated to determine if there was a difference between the countries. The results show that both countries reports predominantly used an ecology and action frame, while British media outlets also used an economic frame. Both countries reported with primarily a negative and neutral tone. The implications of these findings for crisis communication managers are discussed.
129

Effects of Deepwater Horizon Crude Oil on Visual Function in Teleost Fishes

Magnuson, Jason T 08 1900 (has links)
The Deepwater Horizon oil spill released millions of barrels of oil into the Gulf of Mexico, impacting economically and ecologically important fishes. Polycyclic aromatic hydrocarbons (PAHs) present in the oil have been shown to cause developmental impairments in early life stage fishes, such as morphological and behavioral changes related to eye formation and visual processing following PAH exposure. Prior research reported reduced eye growth in open water, pelagic species, as well as reduced photoreceptor-specific transcription factors associated with eye development following exposure to crude oil. Though changes in transcriptomic-level pathways associated with vision and visual processing have been reported, it has yet to be determined how these changes relate to physiological or behavioral-level effects in fish. Therefore, the present studies evaluated the effect of weathered crude oil on eye development and visual function in mahi-mahi, red drum, sheepshead minnow, and zebrafish larvae. Fish were assessed through several visually-mediated behavioral assays, analyzed histologically and immunohistologically, along with subsequent transcriptomic analyses and associated gene expression changes. Larvae exposed to crude oil experienced significantly reduced abilities to exhibit optomotor or optokinetic responses relative to controls, with associated reductions in retinal development. Furthermore, genes associated with eye development and phototransduction were downregulated, with subsequent decreases in the immunofluorescence of neurological connections within the retina and a choroid-specific increase in apoptotic activity. We related oil-induced transcriptomic-level effects to morphological, physiological, and behavioral-level impairments in larval teleost fishes.
130

Photoinduced Toxicity in Early Lifestage Fiddler Crab (Uca longisignalis) Following Exposure to Deepwater Horizon Spill Oil

Taylor, Leigh M. 12 1900 (has links)
The 2010 Deepwater Horizon (DWH) oil spill resulted in a large release of polycyclic aromatic hydrocarbons (PAH) into the Gulf of Mexico. PAH can interact with ultraviolet radiation (UV) resulting in increased toxicity, particularly to early lifestage organisms. The goal of this research was to determine the sensitivity of fiddler crab larvae (Uca longisignalis) to photo-induced toxicity following exposure to Deepwater Horizon spill oil in support of the DWH Natural Resource Damage Assessment. Five replicate dishes each containing 20 larvae, were exposed to one of three UV treatments (10%, 50%, and 100% ambient natural sunlight) and one of five dilutions of water accommodated fractions of two naturally weathered source oils. A dose dependent effect of PAH and UV on larval mortality was observed. Mortality was markedly higher in PAH treatments that included co-exposure to more intense UV light. PAH treatments under low intensity sunlight had relatively high survival. These data demonstrate the importance of considering combined effects of non-chemical (i.e. UV exposure) and chemical stressors and the potential for photo-induced effects after exposure to PAH following the Deepwater Horizon spill.

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