Dissertations / Theses: 'Marine exploration'

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Ropars, Benoît. "Un vecteur robotique polyvalent pour l'exploration sous-marine faible fond." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS125/document.

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Depuis maintenant près d’un siècle, des robots sous-marins ont été développés afin de réaliser des tâches spécifiques aux besoins des grands acteurs historiques du domaine (militaires, pétroliers, câbliers ou explorateurs benthiques) sans vraiment se soucier de la polyvalence et de la modularité de la plateforme. L’objectif de cette thèse est d’avoir une réflexion sur une solution technologique et scientifique avec comme domaine applicatif l’environnement faible fond ou confiné. Il s’agit en d’autres termes de concevoir un robot sous-marin que l’on peut faire évoluer aisément tant sur le plan mécanique, électronique qu’informatique. Cet objectif impose de proprement conceptualiser cette « polyvalence » en s’attachant à apporter de l’abstraction dans l’architecture de contrôle que se soit au niveau de l’automatique avec l’expression de la polyvalence liée à l’étage d’actionnement ou de l’informatique avec une architecture basée services, pouvant être composés, afin de répondre à la diversité des besoins applicatifs. L’ensemble de ces travaux a pour point de départ le robot Jack mis au point par l’entreprise Ciscrea, partenaire industriel, qui apporte un aspect économique à la nécessité de développer une solution polyvalente pouvant être décliné en une gamme de produits. Ce manuscrit traite de la conception, la réalisation et l’expérimentation de ce vecteur que ce soit en piscine où en environnement réel
Since almost a century, underwater robots have been developed in order to respond to the specific needs of historical actors of the domain (military, hydrocarbons exploitation, underwater cabling or benthic exploration), without addressing specifically the question of versatility or modularity of the underwater platform. This thesis aims to address these questions on a technological solution dedicated to shallow water or confined environment. In other words, the objective is to realise an underwater system, able to evolve on the mechanical, electronical or software aspects. This requires to properly conceptualise this « versatility » with an abstraction of the control architecture, on the actuation aspect, with the expression of the versatility linked to the actuation systems, or on the software architecture level, with a Service-Oriented-Architecture (SOA) approach, in order to tackle the diversity of the application requirements. This study is based on the Jack system, developed by the Ciscrea Company, which is the industrial partner of this project, and brings the economical aspect as a central requirement. This underlines another view of the versatility question, the development of a range of product for the Ciscrea Company.This thesis proposes the conception, realisation and experimentation of such a versatile underwater system, with test-tank and field validation

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Wong, Yee-yung Bernard. "An exploration of Hong Kong's container port position in Southern China in the next ten years." [Hong Kong] : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13762047.

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Boonzaier, Lisa. "Marine protected areas : a global exploration of their quantity and quality." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46707.

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Expansion in the number and extent of marine protected areas (MPAs) has been dramatic during the past century, but coverage remains limited and there are concerns that many MPAs are failing to meet their objectives. After updating the global database of MPAs maintained by the Sea Around Us, new estimates of global marine protected area were calculated and revealed a degree of progress towards protecting at least 10% of the global ocean by 2020. It is estimated that more than 6,000 MPAs covering 3.27% of the world’s oceans (∼11.9 million km²) have been designated to date. The protection these MPAs offer is generally weak with about one-fifth (∼2.2 million km²) of their combined area designated as no-take (i.e., where fishing and other extractive activities are prohibited). Additional large tracts of ocean will need to be protected to reach the 10% target, and hypothetical scenarios for such expansion were investigated. To improve understanding of the likely conservation effectiveness of MPAs, trends in their management effectiveness were explored. Results from a self-administered survey questionnaire, distributed to managers and other experts associated with a random sample of MPAs from around the world, revealed a wide range of MPA management effectiveness across different socioeconomic contexts. The results were intended to inform a model of MPA management effectiveness based on socioeconomic, governance and other contextual variables, but no clear relationships between contextual variables and MPA management effectiveness were identified. Overall, the survey findings confirmed results of other studies: while some MPAs are well supported with funding, staff and equipment, others lack even basic management elements. Additional research is essential to understanding the issues preventing MPAs from meeting their objectives, including effectively contributing to biodiversity conservation.

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Patil, Shrikant Malgonda. "Genomics enabled exploration of the marine planktonic diatom genus Pseudo-nitzschia." Thesis, Open University, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705180.

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Pseudo-nitzschia multistriata is a toxic marine planktonic diatom that blooms regularly in the Mediterranean Sea. The species has a heterothallic mode of reproduction with two distinct mating types. This thesis aimed at exploring the molecular underpinnings of different stages of the sexual reproduction phase in Pseudo-nitzschia multistriata using genomics and transcriptomics approaches. A comparative transcriptomics approach was used to explore the molecular mechanisms involved in the early stages of sexual reproduction in which the opposite mating type strains engage in complex chemical communication and subsequent intracellular signaling. The present thesis identified a number of MT specific genes that are differentially regulated during sexual reproduction. The majority of these MT specific genes could not be annotated using homology based methods, suggesting that they have unique roles in this species. Further, substantial differences between the two mating types were observed in terms of metabolic processes employed during sex. Interestingly, a cell cycle arrest, a phenomenon extensively studied in yeasts, at the onset of the sexual phase was observed in Pseudonitzschia multistriata. Moreover, the genome of Pseudo-nitzschia multistriata along with other four diatom genomes was searched to look for the genes involved in meiosis. Although the majority of meiosis related genes could be identified, a few meiosis specific genes seem to be absent in diatoms, representing a case of lineage specific independent loss, observed in other sexually reproducing species. Lastly, genetic modification methods such as biolistic transformation and chemical mutagenesis were established for gene function studies in this species and the biolistic transformation is already being used to decipher the function of selected sex specific genes identified from RNA-seq experiments.

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Ochs, Addison T. "An Exploration into the Identification, Etiology, and Distribution of Idiopathic Blindness in the American Lobster, Homarus Americanus." W&M ScholarWorks, 2019. https://scholarworks.wm.edu/etd/1563899053.

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Idiopathic blindness is an environmental disease observed in the American lobster, Homarus americanus H. Milne Edwards, 1837. The only diagnostic assay for idiopathic blindness has been the histological assessment of the eye, which is a time consuming, invasive, and a delicate procedure. I investigated several tools, including the otolaryngoscope and enhanced counterstaining using Bouin’s fixative as alternative, rapid methods for the detection of idiopathic blindness in lobsters. I applied these new diagnostic techniques to toxicology studies to explore a possible lead on the etiology of this condition. Divalent manganese is a well-established neurotoxin released from sediments under hypoxic conditions. Previous studies have shown that the metal exhibits a high affinity for nervous tissue in the confamilial Norway lobster, Nephrops norvegicus. With this prior knowledge, an acute exposure study was designed to expose H. americanus to 0, 20, 80, 150, and 300 mg Mn L-1 (ppm) for 96 hrs. The objectives were to explore disparities in Mn accumulation within various tissues, and determine a non-lethal or sublethal exposure concentration to be used in a chronic exposure study. A positive correlation between Mn accumulation and exposure concentration was observed in all tissue types. The metal was shown to have a consistent pattern of affinity with respect to internal tissues: Hemolymph > optic nerve > brain > hepatopancreas = muscle. A chronic exposure study was designed to investigate the potential link between Mn exposure and idiopathic blindness. That study consisted of a seven week exposure to 150 ppm Mn, with regular assessment of the eyes of the animals using the otolaryngoscope, histological analysis as an endpoint, and comparisons of Mn in the tissues. Animals that molted in the chronic exposure study were found to have very high levels of Mn in their exoskeletons compared to those that had not molted. There was no apparent relationship between Mn exposure and blindness. Alternative theories concerning the etiology of this disease should be considered in future studies.

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Wong, Yee-yung Bernard, and 王宜勇. "An exploration of Hong Kong's container port position in Southern China in the next ten years." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31951065.

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Voser, Tanja M. "Marine Biodiscovery - An Exploration of Chemical Diversity, Antibiotic Discovery, and Invertebrate Natural Product Chemistry." Thesis, Griffith University, 2022. http://hdl.handle.net/10072/414294.

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This thesis covers a wide range of research on marine natural products with a focus on their role in drug discovery. Chapter 1 starts with a general introduction to marine natural product chemistry, describing current trends and problems. It gives an insight into the importance of the discovery of new antibiotics in this pressing time where multidrug-resistant bacteria are on the rise. Chapter 2 is a meta-analysis of current trends in marine microbial natural product research and an analysis of how much of their chemistry overlaps with the chemistry of terrestrial microbial natural products. Over the past decade, research has greatly shifted to focus on marine microbial natural products, at the expense of marine macro-organism studies. An assessment of the structural overlap between 55,817 published marine and terrestrial microbe and marine macroorganism natural products, using structural fingerprints and scaffold clustering, was enlightening. The results showed that currently 76.7% of the chemistry found in marine microbes is vastly similar to the chemistry isolated from terrestrial microbes. This overlap is mainly due to the use of terrestrial isolation and culturing methods that select for the growth of terrestrial-like bacteria instead of unique marine bacteria. As a result, the unique chemistry associated with truly marine microbe species that are in close symbiotic relationships with marine macro-organisms is being missed. Chapter 3 describes the antimicrobial assay development and screening of a large collection of Australian marine invertebrate specimens for activity against four different strains of bacteria. It resulted in 12.5% of all the specimens tested, showing activity against the drugresistant strain of Staphylococcus aureus (MRSA) but lower bioactivity rates against Pseudomonas aeruginosa (0.76%) and Escherichia coli (0.76%). This illustrates how much harder it is to find activity against Gram-negative bacteria such as P. aeruginosa and E. coli. To investigate this challenge further, drug combination screening was undertaken to assess the potential of resurrecting antibiotics, for the use against bacterial strains that have developed resistance, by combining the antibiotic with marine invertebrate extracts. The combinatorial assays were unsuccessful, thus for further investigations I concentrated on the specimens that exhibited activity in the main assay. Analysis of the sponge specimen Aaptos aaptos that showed activity against S. aureus resulted in the isolation of demethylaaptamine as the bioactive component. Small quantities of a series of peptides with molecular weights in the range of 3,000- 4,000 Da were also isolated from the sponge. Unfortunately, a detailed structure determination could not be undertaken due to COVID-19 state border restrictions, which prevented recollection of the sponge. The subsequent two chapters report on the chemistry of antimicrobial bioactive marine invertebrate extracts. Chapter 4 describes the structures of two new betaine molecules isolated from the bryozoan Amathia lamourouxi. Their structures were determined through analysis of 1D and 2D NMR and mass spectrometric data. Crude extracts of the specimen showed antimicrobial activity at 2.5 mg/mL. Although the yield of active compounds was too small to be completely isolated and identified they were associated with brominated alkaloids. Unfortunately, recollection of this species was also hindered by state border closure due to the COVID-19 pandemic. Chapter 5 describes the isolation and identification of two new amphiphilic polyamines that together with a mixture of relatives were extracted from the marine sponge Aaptos lobata. The two pure compounds and the mixture of amphiphilic compounds showed moderate bioactivity against both drug sensitive and resistant S. aureus, and P. aeruginosa. Chapter 6 describes a multiplatform investigation of the chemistry of the ascidian B. leachii. This species was targeted because it had a similar chemical profile to Aaptos aaptos, small alkaloid and large (>3500 Da) peptide and was more accessible after the COVID-19 state border closures. The investigation used different analytical tools like LC-MS and advanced NMR techniques, including DOSY to characterise the diversity of compounds found in the mixture, while MALDITOF imaging was used to identify the specific locations of these metabolites within the ascidian tissue. This study demonstrated the power of MALDI imaging to provide an insight into the chemical ecology of marine species and helped to establish relationships between marine invertebrates and their associated microorganisms. This finding will aid future specific targeting of tissue regions within marine invertebrates for symbiotic microbe isolation and identification of natural products. Finally, Chapter 7 combines and discusses all the findings of this thesis and examines the future of marine drug discovery. The research reported here has explored the chemical diversity of microbial natural products, discovered new compounds, some with antimicrobial activity, and investigated the chemistry of marine invertebrates and their interesting symbiotic relationship with microorganisms.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Le, Van Tuyen. "Exploration de la chimiodiversité d'un Penicillium restrictum d'origine marine par approches métabolomique et lipidomique." Thesis, Nantes, 2020. http://www.theses.fr/2020NANT4051.

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Cette thèse s’inscrit dans un contexte d’investigations du métabolome de souches fongiques marines en vue de l’étude des interactions chimiques entre organismes marins et de la valorisation de produits naturels. La souche Penicillium restrictum MMS417 a été isolée de moules Mytilus edulis. Lors d’un screening biologique réalisé au sein du laboratoire MMS (Mer, Molécules, Santé), cette souche a présenté une activité cytotoxique sur lignée cellulaire tumorale. Notre travail s’est donc porté sur cette souche avec trois axes de recherche : premièrement, une approche OSMAC couplée à un profilage métabolique par UHPLC-HRMS/MS a été réalisée sur 7 milieux de culture, dont un milieu original à base d’extrait de moules (MES -Mussel Extract Sucrose). Deux conditions osmotiques pour chaque milieu ont été utilisées : l’une utilisant de l’eau distillée (ED) et l’autre de l’eau de mer reconstituée (EDM). L’étude métabolomique non-ciblée et la construction du réseau moléculaire de l’extrait MES-EDM ont montré que la souche MMS417 exprimait spécifiquement la voie de biosynthèse aboutissant à des composés de type pyran-2-one sur milieu MESEDM dont des analogues originaux. A partir d’une culture à grande échelle, des travaux d’isolement et de purification guidés par la spectrométrie de masse puis d’analyse structurale ont abouti à la description de douze pyran-2-ones dont sept produits naturels originaux. Une évaluation biologique préliminaire de certains de ces composés a été réalisée (cytotoxicité sur lignée cancéreuse humaine KB, tests antibactériens, test anti Quorum Sensing), ainsi qu’une évaluation in silico d’inhibition de la protéine phosphatase PTP1B. Le second axe de recherche a concerné l’étude de la biosynthèse des différentes pyran-2-ones produites par cette souche. Une étude cinétique sur milieu MES-EDM a été effectuée pendant une durée 11 jours pour comprendre l’enchaînement des différentes étapes biosynthétiques menant à la production des pyran-2-ones observées chez MMS417. Un réseau moléculaire « dynamique » a été élaboré à partir des profils UHPLC-HRMS/MS, qui montre l’évolution des clusters d’ions au cours de la croissance fongique. L’analyse ciblée de l’évolution cinétique du sous-réseau des pyran-2-ones, et l’isolement d’un précurseur biosynthétique original, a permis de proposer des hypothèse sur cette voie de biosynthèse. Enfin, une troisième approche a concerné l’étude du lipidome de la souche MMS417, celle-ci produisant une fraction lipidique extrêmement abondante sur milieu MES-EDM. Pour cela, les extraits issus de l’étude OSMAC ont été analysés à la fois par UHPLC-HRMS (méthode lipidomique, ionisations positive et négative) et par profilage GC-MS des extraits lipidiques totaux après transesterification en esters méthyliques d’acides gras. Une analyse multi-blocs a été développée pour concaténer et traiter de façon globale les quatre jeux de données disponibles : profils UHPLC-HRMS « métabolites spécialisés », profils « lipides-(+/-) » et profils « GC-MS acides gras ». Cela a mis en évidence l’influence de la présence de moules et d’eau de mer sur la production de globale de lipides et en particulier de certains acides gras inhabituels
This thesis falls within the context of investigations of the metabolome of marine fungal strains for the study of chemical interactions between marine organisms and the valorization of natural products. A Penicillium restrictum MMS417 strain was isolated from blue mussels Mytilus edulis. During a biological screening carried out in the MMS laboratory (Mer, Molécules, Santé), this strain exhibited a cytotoxic activity on a tumor cell line. Our work, therefore, focused on this strain with three scopes of research: first, an OSMAC approach coupled with UHPLC-HRMS/MS metabolic profiling was carried out on 7 culture media, including an original medium based on mussel extract (MES -Mussel Extract Sucrose). Two osmotic conditions were also used for each medium: one using distilled water (ED) the other using artificial seawater (EDM). An untargeted metabolomics study together with the construction of the molecular network of the MES-EDM extract showed that the MMS417 strain specifically expressed on MES-EDM medium a biosynthetic pathway leading to pyran-2-one type compounds including original analogues. From a large-scale culture, a mass spectrometry- guided isolation and purification work followed by structural analyses resulted in the description of twelve pyran-2-ones, including seven original natural products. A preliminary biological evaluation of some of these compounds was carried out (cytotoxicity on human cancerous line KB, antibacterial tests, anti Quorum Sensing test), as well as an in silico evaluation of inhibition of the PTP1B protein phosphatase. The second line of research concerned the study of the biosynthesis of the different pyran-2-ones produced by this strain. A time-series study on the MES-EDM medium was carried out for 11 days to understand the sequence of the different biosynthetic steps leading to the production of pyran-2-ones observed in MMS417. A "dynamic" molecular network was developed from UHPLC-HRMS/MS profiles, which showed the evolution of ion clusters during fungal growth. The targeted analysis of the kinetic evolution of the pyran-2-ones subnetwork, and the isolation of an original biosynthetic precursor, allowed us to propose hypotheses on this biosynthetic pathway. Finally, a third approach concerned the study of the lipidome of the MMS417 strain, this latter producing an extremely abundant lipid fraction on MES-EDM medium. For this purpose, extracts from the OSMAC study were analyzed both by UHPLC-HRMS (lipidomic method, positive and negative ionizations) and by GC-MS profiling of the total lipid extracts after transesterification into fatty acids methyl esters. A multi-block analysis has been developed to concatenate and comprehensively process the four available datasets: UHPLC-HRMS “specialized metabolites” profiles, “lipid - (+/-)” profiles, and “GC-MS fatty acid” profiles. This highlighted the influence of the presence of mussel and seawater on the production of lipids and on some unusual fatty acids

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Millar, Sarah Louise. "Science at sea : voyages of exploration and the making of marine knowledge, 1837-1843." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29014.

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This thesis is about the historical geography of scientific knowledge production at sea. It focuses on three expeditions of exploration and discovery undertaken, respectively, by France, the United States of America, and Britain, that in the late 1830s sailed into the southern oceans. These voyages marked the last such expeditions to travel by sail alone and came before an acknowledged period of specialized interest in investigating the oceans and the marine environment, exemplified by the sailing of HMS Challenger in 1872. The expeditions share a commonality of period and of destination: their study together provides a hitherto overlooked opportunity to analyse practices of experimentation on, and investigation of, the natural history and physical properties of the marine environment that were integral to the construction of scientific knowledge about the oceans at that time. By attention to archival records, personal correspondence, diaries, published travel narratives and representations of marine phenomena in the form of illustrations, sketches, preserved specimens and displays of numerical material, this thesis examines quotidian shipboard practices to show how the production of scientific ‘facts’ was a matter of constant negotiation between people, weather, instruments and vessels – that occurred as a by-product of the running of the ship as well as of more defined programmes of study by civilian naturalists and naval staff. Informed by work in the history of science, Science and Technology Studies (STS) and Actor-Network Theory (ANT), this thesis highlights how attending to practice in the ambiguous, heterotopic space that was the expedition vessel can reveal the origins of a new, specialized, discipline: what I call here a proto-oceanography. This covers those scientific practices undertaken primarily at sea and from the ship: depth measurement, sea temperature and chemistry, the height of waves, collection of marine specimens and coastal topography, but not those primarily land-based activities such as astronomy, meteorology and terrestrial magnetism. By focusing on work carried out on board ship rather than on land, this thesis offers new insights into the practices of marine investigation and experimentation and the complexities of interrogating a space which was visualised primarily through instruments. This thesis examines how at-sea cultures of collection, measurement and representation can inform geographically nuanced analyses of the production of scientific knowledge.

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Boussuges, Alain. "Exploration de l'hemostase dans les accidents de decompression secondaires a la plongee sous-marine." Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20846.

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Appleby, T. "Fisheries law in action : an exploration of legal pathways to a better managed marine environment." Thesis, University of the West of England, Bristol, 2015. http://eprints.uwe.ac.uk/25169/.

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This narrative addresses the issue of fisheries law, a specialist area combining aspects of international law, EU law, legislation from the UK and the devolved administrations and the common law. The research appraised and analysed marine fishing rights, the ownership of the UK marine fishery and the establishment of marine protected areas both under UK and aspects of EU law. The research adopted a doctrinal method triangulated via professional examples adopting aspects of action research. The scientific research, on which this research drew, established that there is a serious decline in UK fisheries and an urgent need to bring in measures to safeguard the fishery. The research found significant failings in the common law public right to fish, which designated the UK’s entire marine area as a fishery without apparent reasonable limitations as to use. It found that the absence of a stated public owner of the fishery with clear public duties makes it difficult to secure the public interest. It also highlighted the absence of clarity in the creation of derivative rights in the public fishery such as fishing quota, estimated in 1999 to be worth £1 billion. The research demonstrates the significant shortfall in the number of statutory marine protected areas created under the Marine Acts and raises concerns that these statutory measures could lead to paper parks with no active management measures. It shows the effectiveness of the application of the Habitats Directive to protect European marine sites and concludes that other European legislation could similarly be used to protect the marine environment from fisheries. It also found a lack of a coherent narrative relating to the mechanics and powers and duties of UK fisheries managers and concluded that there should be more comprehensive guidance on UK fisheries law, as the last comprehensive fishery texts date from the nineteenth century. The research recommends new Fisheries Acts to remedy some of the apparent defects in UK fisheries law.

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Liu, Shuai [Verfasser]. "Bioactive Secondary Metabolites from Marine-Derived Fungi and Exploration of Fungal-Bacterial Co-Cultivation / Shuai Liu." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1122263600/34.

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Key, Kerry W. "Application of broadband marine magnetotelluric exploration to a 3D salt structure and a fast-spreading ridge /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3112859.

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Mocnik, Arianna. "Processing and analysis of seismic reflection data for hydrocarbon exploration in the plio-quaternary marine sediments." Doctoral thesis, Università degli studi di Trieste, 2012. http://hdl.handle.net/10077/7763.

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2010/2011
RIASSUNTO Durante i tre anni di Dottorato di Ricerca sono state studiate ed applicate delle specifiche tecniche di analisi del segnale sismico a riflessione mirate alla identificazione di livelli di idrocarburi all’interno di sedimenti marini Plio-Quaternari. Particolare attenzione è stata inoltre dedicata alla correlazione tra questi reservoir di idrocarburi e le strutture geologiche profonde che ne possono aver favorito l’accumulo. Le metodologie utilizzate sono costituite da: 1) metodi diretti, chiamati Direct Hydrocarbon Indicators, che si basano sull’osservazione delle caratteristiche acustiche di un riflettore legato a gas; 2) metodo AVO-Amplitude Variation with Offset, che si basa sull’analisi delle variazioni delle ampiezze di riflessione in funzione dell’offset, fortemente dipendente dalla presenza di idrocarburi; 3) calcolo degli attributi sismici, grazie al quale è possibile estrarre dall'onda sismica informazioni supplementari non direttamente evidenziate nei profili sismici standard osservabili dal dato originale, che contribuiscono a verificare la presenza di gas. E’ questo il caso analizzato nel Canale d’Otranto: lungo il profilo sismico MS-29 si sono riscontrate evidenze di possibili accumuli di idrocarburi all’interno della sequenza Plio-Quaternaria; gli attributi sismici sono stati applicati al bright spot osservato, sia in fase pre-stack che in fase post-stack; il metodo è risultato fondamentale per individuare le caratteristiche di ampiezza, fase e frequenza che caratterizzano un riflettore legato a idrocarburi. L’analisi AVO, ha consentito di rinvigorire l’ipotesi di un livello saturo a gas. Il bright spot osservato è ubicato in corrispondenza del margine della piattaforma carbonatica Apula. Questa avrebbe costituito l’elemento strutturale all'origine della deformazione dei sedimenti in una blanda anticlinale: in essa sarebbero stati intrappolati gli idrocarburi grazie allo sviluppo di fenomeni di compattazione differenziata tra i sedimenti di copertura di bacino e di piattaforma. Anche in Adriatico Centrale l’analisi di un possibile livello a gas lungo il profilo sismico ADRIA-95 ha fatto supporre l’esistenza di orizzonti saturi a gas all’interno della serie sabbiosa-argillosa Plio Quaternaria. In questo caso è stato effettuato l’analisi del bright spot mediante attributi sismici e AVO, i quali hanno confermato l’ipotesi. Oltretutto, sul dato sismico è stato eseguito il re-processing mirato alla definizione delle unità sedimentarie che caratterizzano la sequenza Post-Messiniana dell’area attraversata dal profilo. Sulla base dei risultati ottenuti è stato proposto l’utilizzo degli attributi per il miglior riconoscimento delle geometrie degli strati, da cui si è potuta affinare l’interpretazione dell’assetto geologico. Si è osservato nel dettaglio che l’evidenza di gas risulta collocata in corrispondenza di strati deformati da spinte profonde legate a domi salini triassici. Oltre a questi casi di studio, sono state effettuate delle analisi di possibili livelli saturi in gas riconosciuti lungo profili sismici ubicati nel Bacino Mediterraneo, in particolare nell'offshore della Sardegna Occidentale, nel Canale di Sicilia e nel Bacino Levantino. AVO e attributi sismici sono serviti a validare l’ipotesi di presenza di idrocarburi nei sedimenti Plio-Quaternari, valutando le correlazioni ai diversi contesti geologici in cui si sono impostati. L’effetto delle procedure è stata anche testata al caso specifico dei gas-idrati, con l’obiettivo di definire se un riflettore individuato lungo un profilo sismico della Penisola Antartica, potesse essere un bottom simulating reflector (BSR); questo rappresenta la tipica manifestazione sismica di gas idrato. Le procedure di AVO sono risultate efficaci anche in presenza di idrocarburi che si trovano in specifiche condizioni di temperatura, pressione e composizione. Le medesime procedure di analisi del segnale sismico sono state quindi applicate a dati che furono acquisiti con diverse sorgenti, modalità di registrazione e geometrie di acquisizione, in funzione dei diversi target da raggiungere. Grazie a ciò è stato possibile fare un confronto tra le varie risposte del metodo a questi “parametri" e giudicare le condizioni del dato originale che consentono di ottenere i risultati più soddisfacenti. L'insieme delle analisi effettuate conferma l'utilità di un approccio sempre più avanzato di analisi AVO e di Attributi Istantanei via via più complessi. Suggerisce inoltre l'opportunità di correlare la presenza di idrocarburi agli elementi geologici presenti, riconoscibili attraverso una accurata interpretazione del dato sismico.
ABSTRACT During the three years of the PhD course specific techniques of analysis of seismic reflection data have been studied and applied, aimed at identifying the hydrocarbon saturated levels within Plio-Quaternary marine sediments. Particular attention was also devoted to the correlation between these hydrocarbon reservoirs and some deep geological structures that have favored their accumulation. The used techniques consist of: 1) direct methods, called Direct Hydrocarbon Indicators, which are based on observation of the acoustic characteristics of a gas-related reflector; 2) AVO Amplitude Variation with Offset method, which is based on the analysis of amplitude variations as a function of the offset, strongly influenced by the presence of hydrocarbons; 3) estimation of seismic attributes, from which additional information, not directly evidenced in standard seismic data, can be extracted from the reflected wave, thus contributing to verify gas presence. A first case study has been analyzed in the Otranto Channel: evidences of possible hydrocarbon accumulations along the seismic profile MS-29 have been shown within the Plio-Quaternary sequence. Seismic attributes have been applied to the observed bright spots in both pre-stack and post-stack data; the method has resulted essential to identify the characteristics of amplitude, phase and frequency parameters, that usually contribute to define an hydrocarbon related reflector. AVO analysis has allowed to strengthen the hypothesis of a gas filled layer. The studied bright spots is located over the margin of the Apulia Carbonate platform. This would represent the structural feature at the origin of the sediments deformation in a gentle anticline: here, the hydrocarbons would be trapped due to the development of differential compaction phenomena between the sediments covering the basin and the platform. A possible gas saturated level identified along the seismic profile ADRIA-95 in the Central Adriatic suggested the existence of another reservoir within the Plio-Quaternary sediments. In this case study, the analysis of the bright spots has been achieved with application of seismic attributes and AVO, which have confirmed the hypothesis. Furthermore, re-processing of the seismic data was performed, aimed at the definition of the sedimentary units that characterize the post-Messinian sequence of the area. Based on the obtained results, the attributes analysis were also applied to the improvement of definition of the strata geometries: this allowed the refining of the interpretation. It has been observed, in detail, that the evidence of gas is placed in correspondence of deformed layers by pressures derived from deep Triassic salt domes. In addition to these case studies, some other analysis have been performed after the recognition of possible gas saturated horizons along seismic profiles located in the Mediterranean Basin, especially offshore of West Sardinia, Sicily Channel and in the Levantine Basin. AVO and seismic attributes have been used to validate the hypothesis of the presence of hydrocarbons in Pliocene-Quaternary sediments, also considering the correlations to the different geological contexts in which they are set. Finally, the effect of these procedures was also tested for gas-hydrates, with the aim of defining if a reflector observed along a seismic profile of the Antarctic Peninsula, could be a bottom simulating reflector (BSR), that represents the typical seismic manifestation of gas hydrate. The procedures for AVO are found to be effective even in the typical conditions of temperature, pressure and composition related to the BSRs. The same procedures of seismic signal analysis have been applied to data that were acquired with different sources, recording mode and acquisition geometries, depending on the different target to be reached. Thanks to that, the comparison among the different responses of the methods to these "parameters" has been possible, evaluating the conditions of the original data that could produce the most satisfactory results. All the applied methods confirm the utility of a more and more advanced approach for analysis of AVO and instantaneous attributes increasingly complex. It also suggests the opportunity to correlate the presence of hydrocarbons presence with the geological elements, identified through a rigorous seismic data interpretation.
XXIV Ciclo
1982

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15

Rather, Anna B. "Dreaming of the ocean, I wish I was a fish : an exploration in printmaking." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1313949.

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This project involved a series of linoleum, woodcut, and intaglio prints whose subject matter was derived from my imagination. The inspiration for this work is the ocean and the myriad life forms found there. I perused books on the ocean and created characters from these images. These prints also have a psychological edge and emotional aspect reflecting the state of mind I was in when 1 created them. Putting these ideas together in the intaglio prints as well as using different techniques was the challenge in making this work. My goal was also to explore linoleum and woodcut prints where I used multiple blocks and/or rolled more than one color on a block to achieve a multitude of hues for one image. I found this complex way of making images exciting and feel that the works created have been successfully resolved.
Department of Art

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Ashford, Oliver Simon. "Illuminating the deep : an exploration of deep-sea benthic macrofaunal ecology in the Northwest Atlantic Ocean." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:228c4d19-56a8-41e1-a1da-9ca13fe2eef1.

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Understanding of the fundamental ecology of deep-sea ecosystems remains immature relative to more familiar shallow-water and terrestrial habitats, despite more than two hundred years of scientific investigation. This thesis aims to progress knowledge of deep-sea benthic ecology by the analysis of over three hundred box core samples collected from the Northwest Atlantic continental slope as part of the international NEREIDA programme. Aspects of the ecology of Peracarida (Crustacea) are studied, and this is facilitated by the coupling of a large faunal dataset with extensive environmental information. To further enhance the power of this dataset, phylogenetic and functional characteristics of assemblages are investigated. Using community phylogenetic methodology, it is demonstrated that the peracarid assemblages studied are structured more strongly by variation in environmental parameters than they are by competitive interactions. Analyses demonstrate that the intensity of bottom trawling, seafloor temperature, current speed, food availability, sediment characteristics and physical habitat heterogeneity all influence deep-sea peracarid assemblage biodiversity metrics. Further, the importance of high poriferan biomass for the promotion of peracarid assemblages of high density, biomass, richness and diversity is highlighted. Of relevance to the management of deep-sea ecosystems, the results of this thesis suggest that caution should be exercised when applying species distribution models to data-deficient environments, whilst the location of spatial closures in the NAFO Regulatory Area may not be fully optimal for the protection of all components of diverse benthic assemblages against the impacts of bottom trawling. The importance of deep-sea diversity is demonstrated by the finding of positive biodiversity â ecosystem functioning relationships. However, the form of these relationships is found to be dependent on the biodiversity and ecosystem functioning metrics employed, and a hypothesis for a generalised form of biodiversity â ecosystem functioning relationships is proposed. Finally, this thesis calls for more ambitious deep-sea ecological investigations, and it is hoped that its findings will encourage future research initiatives, helping to further illuminate this enigmatic and fascinating environment.

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Da, Rosa Rafael. "Mécanismes moléculaires et bases génétiques de la capacité de survie des huîtres Crassostrea gigas à des vibrioses : une exploration transcriptomique." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20101/document.

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Les objectifs de cette thèse étaient d'explorer les mécanismes moléculaires et les bases génétiques impliquées dans la survie des huîtres Crassostrea gigas à des maladies infectieuses, en considérant deux souches de Vibrio pathogènes pour l'huître (V. splendidus LGP32 et V. aestuarianus LPi 02/41) qui ont été associées aux phénomènes de mortalités massives d'huîtres en France. Par l'approche transcriptomique de « Digital Gene Expression », nous avons identifié des composants génétiques d'une réponse efficace à des infections par des Vibrio virulents. La capacité de survie des huîtres se traduit par l'expression basale d'une combinaison de 14 gènes hémocytaires, une signature de survie, et par l'induction de différentes fonctions cellulaires au cours de la réponse immunitaire. Une analyse transcriptomique détaillée au niveau individuel a révélé un extraordinaire polymorphisme d'expression basale des gènes, incluant des cas où chez certaines huîtres des transcrits sont absents. Afin de comprendre ce polymorphisme, nous nous sommes intéressés à la caractérisation d'une nouvelle famille de peptides antimicrobiens (PAMs), les big défensines (Cg-BigDef). Nous avons montré que Cg-BigDef est une famille de PAMs composée de trois membres et diversifiée en termes de séquences, d'organisation génomique et de régulation de l'expression des gènes. Les Cg-BigDefs sont codées par des gènes distincts dont l'expression est régulée suivant différents modes en réponse à une infection. Chose intéressante, certaines huîtres n'expriment pas simultanément les trois formes de Cg-BigDef ou dans certains cas, n'en expriment aucune. Nous avons démontré que l'absence d'expression basale de Cg-BigDef est liée à l'absence de gène correspondant dans le génome des huîtres. C'est la première mise en évidence chez un invertébré de variation de présence/absence (PAV) de gènes, un phénomène qui pourrait contribuer à une susceptibilité accrue aux maladies infectieuses
The objectives of this thesis were to explore the molecular mechanisms and genetic bases involved in Crassostrea gigas oyster survival to infectious diseases, considering two Vibrio strains (V. splendidus LGP32 and V. aestuarianus LPi 02/41) pathogenic for oysters which have been shown to be involved in C. gigas mass mortalities in France. By the Digital Gene Expression transcriptomic approach, we have identified some genetic components implicated in a successful response and survival to virulent Vibrio infections. Oyster survival capacity is reflected by the basal expression of a selected combination of hemocyte genes, a 14-gene survival signature, and by the induction of some cellular functions during the oyster immune response. A detailed transcriptomic analysis at individual level revealed an extraordinary interindividual polymorphism in basal gene expression, including cases where some transcripts are fully absent. In order to understand this striking variability in gene expression, we have focused on the characterization of a novel family of antimicrobial peptides (AMP) in C. gigas oysters, the big defensins (Cg-BigDef). We have shown that Cg-BigDef is an AMP family, composed of three members, and diversified in terms of sequences but also in terms of genomic organization and regulation of gene expression. Each Cg-BigDef form is encoded by a distinct gene that follows different patterns of gene regulation upon Vibrio infection. Interestingly, some oysters were shown do not express simultaneously the three Cg-BigDef forms or any Cg-BigDef. We demonstrated that the absence of Cg-BigDef basal gene expression is likely due to the absence of the Cg-bigdef gene in oyster genome. This is the first evidence in an invertebrate of a presence/absence variation (PAV) of genes, a phenomenon that could be associated to a susceptibility to infectious diseases

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Newport, John. "Educating with/in the environment : an exploration and analysis of marine and coastal field studies centres in South Australia /." Title page, abstract and table of contents only, 1999. http://web4.library.adelaide.edu.au/theses/09ENV/09envn558.pdf.

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19

Lasbouygues, Adrien. "Exploration robotique de l’environnement aquatique : les modèles au coeur du contrôle." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS078/document.

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Les robots sous-marins peuvent aujourd'hui évoluer dans des environnements complexes difficilement accessibles à l'Homme pour des raisons de coût ou de sécurité. Ils peuvent donc intervenir dans une grande variété de missions en environnement aquatique. Or, la complexité de ces milieux impose de doter le vecteur robotique d'une autonomie opérationnelle suffisante afin qu'il puisse mener sa mission à bien tout en préservant son intégrité. Cela nécessite de développer des lois de commande répondant aux spécificités de l'application. Ces lois de commande se basent sur des connaissances provenant de différentes disciplines scientifiques ce qui souligne l'interdisciplinarité inhérente à la robotique. Une fois la loi de commande développée, il faut implémenter le contrôleur sur le robot sous forme de logiciel de contrôle basé sur une architecture logicielle temps-réel.Or la conception actuelle des lois de commande, sous forme de blocs "monolithiques", rend difficile l'évolution d'une loi de commande d'une application à l'autre, l'intégration de connaissances provenant d'autres disciplines scientifiques que ne maitrisent pas forcément les automaticiens et pénalisent son implémentation sur des architectures logicielles qui nécessitent la modularité. Pour résoudre ces problèmes nous cherchons à proprement séparer les différentes connaissances afin que chacune soit aisément manipulable, son rôle clair et que les relations établies entre les différentes connaissances soient explicites. Cela permettra en outre une projection plus efficace sur l'architecture logicielle. Nous proposons donc un nouveau formalisme de description des lois de commande selon une composition modulaire d'entités de base appelées Atomes et qui encapsulent les différents éléments de connaissance. Nous nous intéressons également à l'établissement d'une meilleure synergie entre les aspects automatique et génie logiciel qui se construit autour de préoccupations communes telles que les contraintes temporelles et la stabilité. Pour cela, nous enrichissons nos Atomes de contraintes chargées de véhiculer les informations relatives à ces aspects temporels. Nous proposons également une méthodologie basée sur notre formalisme afin de guider l'implémentation de nos stratégies de commande sur un Middleware temps-réel, dans notre cas le Middleware ContrACT développé au LIRMM.Nous illustrons notre approche par diverses fonctionnalités devant être mises en oeuvre lors de missions d'exploration de l'environnement aquatique et notamment pour l'évitement de parois lors de l'exploration d'un aquifère karstique
Underwater robots can nowadays operate in complex environments in a broad scope of missions where the use of human divers is difficult for cost or safety reasons. However the complexity of aquatic environments requires to give the robotic vector an autonomy sufficient to perform its mission while preserving its integrity. This requires to design control laws according to application requirements. They are built on knowledge from several scientific fields, underlining the interdisciplinarity inherent to robotics. Once the control law designed, it must be implemented as a control Software working on a real-time Software architecture.Nonetheless the current conception of control laws, as "monolithic" blocks, makes difficult the adaptation of a control from an application to another and the integration of knowledge from various scientific fields which are often not fully understood by control engineers. It also penalizes the implementation of control on Software architectures, at least its modularity and evolution. To solve those problems we seek a proper separation of knowledge so that each knowledge item can be easily used, its role precisely defined and we want to reify the interactions between them. Moreover this will allow us a more efficient projection on the Software architecture. We thus propose a new formalism for control laws description as a modular composition of basic entities named Atoms used to encapsulate the knowledge items.We also aim at building a better synergy between control and software engineering based on shared concerns such as temporal constraints and stability. Hence we extend the definition of our Atoms with constraints carrying information related to their temporal behaviour. We propose as well a methodology relying on our formalism to guide the implementation of control on a real-time Middleware. We will focus on the ContrACT Middleware developed at LIRMM.Finally we illustrate our approach on several robotic functionalities that can be used during aquatic environments exploration and especially for wall avoidance during the exploration of a karst aquifer

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20

Tost, Brian Christopher. "Low porosity mistaken for natural gas hydrate at Alaminos Canyon, Gulf of Mexico: Implications for gas hydrate exploration in marine sediment reservoirs." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366475207.

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21

Pennell, Alexa Olivia. "The Influence of Petroleum Exploration on the Distribution of Cetaceans in the Gulf of Mexico." NSUWorks, 2011. http://nsuworks.nova.edu/occ_stuetd/186.

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The objective of this thesis was to determine if there were any correlations in the distribution of cetaceans, especially sperm whales (Physeter macrocephalus), pantropical dolphins (Stenella attenuata), bottlenose dolphins (Tursiops truncatus), and Risso’s dolphins (Grampus griseus) in the northern Gulf of Mexico because of the influence of oil and gas production and exploration. This research is important because of the lack of knowledge about the impact of anthropogenic sounds from oil and gas exploration and production (E&P) on cetacean distribution in the Gulf of Mexico. I analyzed cetacean visual line-transect survey results from the Gulf of Mexico for period of 1992 – 2001. I divided this time span into an early period (1992 – 1997) and a late period (1998 – 2001). I overlayed the locations of cetacean sightings and the locations of oil and gas E&P platforms to demonstrate their close association in space, and tested a hypothesis that distribution would shift south correlated with changes in distribution of E&P. I compared the distributions of cetacean sightings in the entire Gulf of Mexico, and separated the Gulf of Mexico into east and west, between the early period and the late period. The east Gulf of Mexico represents an area without oil and gas E&P platforms and the west Gulf of Mexico is the area where oil and gas E&P platforms are located. The null hypothesis for these tests was that there was no difference in cetacean distribution between the early period and the late period. I also compared the distribution of sperm whales, pantropical dolphins, bottlenose dolphins, and Risso’s dolphins in the entire Gulf of Mexico, both east and west, between the early and late periods. I expect if distribution changes were correlated with changes in E&P distribution, then there will be a shift south in the western Gulf. Changes in distribution in the eastern Gulf would not be correlated with E&P. I found that the sightings per unit effort (SPUE) of all cetacean sightings in the entire Gulf of Mexico shifted to the south in the late period, as compared to the early period .The distribution of all cetacean sightings for the late period (1998-2001) was significantly different compared to the distributions of all cetacean sightings in the early period (1992-1997). The SPUE of sperm whale and bottlenose dolphin distributions were shifted to the north in the late period (1998-2001) compared to the early period (1992-1997). While pantropical dolphin distributions were significantly shifted to the south between the two time periods. I observed that the SPUE of all cetaceans sightings in the east Gulf of Mexico for the early period (1992-1997) were shifted to the south compared to the west, which were not different. The SPUE for sperm whales in the east for the early period were marginally shifted to the north in comparison to the west, which were also shifted further north. The SPUE for Risso’s dolphins in the east were shifted further north while in the west SPUE were shifted to the south. The SPUE for pantropical dolphin sightings were shifted to the north in both the east and west regions. While the SPUE for bottlenose dolphin sightings were shifted to the north in both the east and west Gulf of Mexico. My SPUE results suggest that pantropical dolphins, like the total cetaceans examined here, have shifted their distributions in the entire northern Gulf of Mexico to the south. However, in areas of high oil and gas E&P platforms the distributions of sperm whales and bottlenose dolphins did not shift their distributions from the early period to the late period to the south even though these E&P activities have shifted to the south over the past two decades as they expanded into the deeper waters of the northern Gulf of Mexico. Therefore, there is little evidence that large scale changes in the latitudinal distribution of marine mammals in the Northern Gulf have occurred as a result of greater offshore E&P activity.

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22

Roozeboom, Jennifer Elizabeth. "Exploration and application of post-infrared high-temperature infrared stimulated luminescence dating techniques: investigation of marine terrace deposits along the northern San Andreas Fault." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/19050.

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Master of Science
Geology
Joel Q. Spencer
Optically stimulated luminescence (OSL) dating is a relatively new dating method, tangibly introduced in 1985 when Huntley et al. demonstrated the ability to use light-sensitive traps to measure radiation exposure and determine the age of sediment. Quartz and feldspar grains are commonly used for the method, with quartz receiving significantly more attention than feldspars until the past decade. Recent research has improved the practicality of using feldspars as a reliable dosimeter –an appealing notion as the intrinsic properties of feldspars allow them to date older sediment that may lie beyond the reliable range of quartz dosimetry. This work explores and utilizes the contemporary feldspar technique termed post-infrared, high-temperature infrared stimulated luminescence (pIRIR) dating to add to the existing knowledge base of this method, particularly by testing different preheat and measurement temperature combinations. Analysis of the each pIRIR method indicates that the pIRIR signal stimulated at 225°C is more appropriate for dating than the pIRIR signal stimulated at 290°C. Techniques and protocols developed in this work are done so via their application to a marine terrace that is displaced by the San Andreas Fault. Corals from the terrace along the Pacific plate, dated with U-series by Muhs et al. (2002), offer an age estimate. Comparison of the pIRIR ages to the U-series ages yield an underestimation, suggesting the pIRIR method may be more useful as a means of correlating terraces across the fault, than for providing ages of terrace formation.

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23

Navare, Jyoti. "Marine oil spill incidents from sea-going tankers : an idiographic exploration of the spill effects on structure, culture and behaviour in risk and collective incident management." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394099.

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24

Endress, Maxime. "Neuropeptides et phéromones sexuelles impliqués dans le contrôle de la ponte chez la seiche Sepia Officinalis." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC208/document.

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La seiche commune Sepia officinalis est un Mollusque Céphalopode présent sur les côtes Normandes. En Baie de Seine, elle représente la troisième espèce visée par les flottilles hauturière et côtière, ce qui en fait une ressource économique importante pour la région. Dans un contexte de protection de la ressource, l’étude et la compréhension des mécanismes liés à la reproduction représentent un objectif majeur. Cette étude est donc focalisée sur les mécanismes régulateurs de la ponte, et en particulier sur les facteurs impliqués dans l’émission des ovocytes. Des recherches antérieures effectuées au laboratoire ont mis en évidence un contrôle multifactoriel du processus de ponte, avec trois niveaux de régulation. (i) Les neuropeptides sont impliqués dans la perception des paramètres environnementaux, (ii) les facteurs ovariens assurent la régulation paracrine du tractus génital, et (iii) les phéromones sexuelles, tout en interférant avec la ponte, sont suspectées de jouer un rôle important dans le comportement des géniteurs associé à la reproduction. Cette thèse met en lumière le rôle de 2 familles de neuropeptides identifiées récemment : les CCAPs et les FLGamides (ou So-orcokinines B). Ces deux familles participent au transport de l’ovocyte et à la sécrétion capsulaire en agissant sur l’activité contractile du complexe oviducte/glande de l’oviducte et des glandes nidamentaires principales. Ces neuropeptides sont par ailleurs suspectés de jouer un rôle dans la biosynthèse des protéines vitellines et des protéines capsulaires. Parallèlement, des phéromones sexuelles sont exprimées par la glande de l’oviducte et sécrétées avec les protéines capsulaires. Des travaux antérieurs ont permis de caractériser des produits d’expression issus de clivages de type prohormone convertase. Dans cette nouvelle étude, un second mode de clivage a été mis en évidence avec l’identification de produits de clivage de masse moléculaire supérieure à 20 kDa. L’un de ces produits, la phéromone beta, a été produit en système recombinant mais son activité biologique sur l’appareil génital mâle et sur l’oviducte n’a pas été démontrée. Quant aux tests comportementaux, ils n’ont pu être exploités du fait d’un nombre d’animaux testés trop restreint. Enfin, une approche transcriptomique comparative et différentielle réalisée à partir de l’organe olfactif mâle et du pavillon de l’oviducte a permis d’identifier un récepteur candidat à la liaison avec les phéromones sexuelles
The common cuttlefish (Sepia officinalis) is a Cephalopod mollusk found on the Normandy coasts. In the Bay of Seine, it is the third species targeted by offshore and coastal fleets, so it is an important economic resource for the whole region. In a context of resource protection, the study and understanding of its reproductive mechanisms is a major objective. This study is therefore focused on the regulatory mechanisms of egg-laying, and in particular on the factors involved in the release of oocytes. Previous research in the laboratory demonstrated multifactorial control of the egg-laying process, with three levels of regulation: (i) neuropeptides involved in the perception of environmental cues, (ii) ovarian factors providing paracrine regulation of the genital tract, and (iii) sexual pheromones, which are implied in egg-laying and are suspected to play a determining role in the reproductive behavior. This thesis highlights the role of two families of recently identified neuropeptides called CCAPs and FLGamides (or So-orcokinins B). These two families participate in oocyte transport and in egg capsule secretion by acting on the contractile activity of the oviduct/oviduct gland complex and of the main nidamental glands. These neuropeptides are also suspected to play a role in the biosynthesis of yolk and capsular proteins. At the same time, sex pheromones are expressed by the oviduct gland and secreted along with capsular proteins. Previous work made it possible to characterize expression products resulting from cleavages of the prohormone convertase type. In this new study, a second mode of cleavage is highlighted, evidenced by the identification of cleavage products with MWs greater than 20 kDa. One of these products, beta pheromone, was produced in a recombinant system but its biological activity on the male reproductive system and on the oviduct was not demonstrated. As for behavioral tests, they were not exploited because the number of animals tested was too small. Finally, a comparative and differential transcriptomic approach of the male olfactory organ and the oviduct pavilion evidenced a candidate receptor expected to bind to sex pheromones

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Szitkar, Florent. "Signature magnétique des sites hydrothermaux dans différents environnements : contributions des données de haute résolution." Paris, Institut de physique du globe, 2013. http://www.theses.fr/2013GLOB0005.

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Barnett, Michael Leonard. "Human error and maritime safety : an exploration of the causes of marine casualties and the design of simulator-based training programmes to develop the skills of safe vessel control." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325708.

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Schoening, Timm [Verfasser]. "Automated detection in benthic images for megafauna classification and marine resource exploration: supervised and unsupervised methods for classification and regression tasks in benthic images with efficient integration of expert knowledge / Timm Schoening." Bielefeld : Universitätsbibliothek Bielefeld, 2015. http://d-nb.info/1068001402/34.

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Péton, Loïc. "Penser l'existence de vie dans les profondeurs marines au XIXe siècle : entre abîme impossible et origine du vivant (1804-1885)." Thesis, Brest, 2016. http://www.theses.fr/2016BRES0001/document.

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Abîme : gouffre, enfer, chaos. En marge de la civilisation occidentale, ténébreuses et dévalorisées, les profondeurs marines furent pensées et expérimentées au cours du XIXe siècle. Sur le pont du navire, le naturaliste s’appropriait les techniques de pêche et fouillait les antres d'un univers obscur pour récolter une faune méconnue.Cette thèse démontre l'importance de diverses influences, provenant de contextes différents, qui modelaient les théories au sujet de l'existence de vie dans cet univers. L'idée d'une vie limitée, à partir d'un certain niveau de profondeur, domina, notamment avec la théorie azoïque (1843) du Britannique Edward Forbes (1815-1854). Selon nous, elle formait un horizon ultime, telle une finitude anthropomorphique appliquée à la répartition des animaux. Par la suite, la représentation d'une vie présente en tous lieux – une « vie triomphante » – la remplaça au cours de la décennie 1860 pour former la base de notre savoir actuel, à un moment où l'abîme était perçu tel un antre du passé hébergeant des « fossiles-vivants ». Ces représentations constituaient les réverbérations d'une culture et d'intérêts que nous explicitons.Ce travail révèle également une focalisation des savants sur certains objets, comme le fond marin, repère fixe perçu par un filtre terrestre couplé à une analogie avec l'altitude. Le visage bathymétrique de l'océan profond se dessinait alors, tandis que le câble télégraphique devenait une interface de renouveau pour le savoir propre à l'abîme. Une volonté d'ériger un panorama absolu de l'océan parcourait cette période, cela par une extrapolation horizontale (toutes mers) et verticale (toutes profondeurs) de quelques observations relevées
Abyss : chasm, hell, chaos. On the fringe of the western civilization, the marine depths were regarded as impenetrable and were depreciated before being studied during the 19th century. At sea, the naturalist took over fishing techniques and rummaged through a dark universe to collect an unknown fauna.This thesis shows the importance of the various influences that shaped the scientific theories about the existence of life in the abyss.The idea of a limit for marine life, beneath a given depth, dominated, notably using the azoic theory (1843) of the British Edward Forbes (1815-1854). According to us, this theory was a “final horizon”, that is to say an anthropomorphic finitude placed on the animal distribution. Later, the representation of a life inhabiting every place – a “triumphant life” – replaced it during the 1860s to form the basis of our current knowledge, at a time when the abyss was regarded as a “lair of the past” containing “living-fossils”. These representations were reflections of a culture and of interests.This work also reveals that the scientists focused on some objects like the seabed, which was a fixed mark considered through a terrestrial view linked to an analogy with altitude. The bathymetric face of the ocean emerged while the submarine cable became an “interface of revival” for the knowledge about the abyss. The will to design an “absolute panorama” of the ocean was present in this period, using horizontal (every sea) and vertical (every depth) extrapolations from a few facts

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Mohamadian, Sarvandani Mohamadhasan. "Seismic tomography of an amagmatic ultra-slow spreading ridge." Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS467.

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Les dorsales ultra-lentes quasi-amagmatiques constituent une nouvelle catégorie de dorsales océaniques caractérisées par une accrétion crustale, exposant sur le fond marin des quantités considérables de péridotites provenant du manteau. L’étude de la contribution des processus tectoniques, magmatiques et d’autres processus impliqués est nécessaire pour obtenir un modèle conceptuel complet des dorsales océaniques à accrétion ultra-lente. L’imagerie des structures de la croûte et du manteau supérieur peut nous aider à comprendre les activités géologiques passées et actuelles sur les dorsales à accrétion océanique ultra-lente. L’objectif du projet est de comprendre la croûte océanique formée dans une dorsale à accrétion ultra-lente appelée ride sud-ouest indienne, à faible apport de magma. Notre projet de recherche est basé sur le traitement et la modélisation de données sismiques actives et passives dans la partie la plus orientale de la dorsale Sud-Ouest Indienne. L’acquisition des données géophysiques a eu lieu en 2014 lors de la campagne SISMOSMOOTH, à bord du N/O Marion-Dufresne. Nous avons analysé les enregistrements des composantes verticales de 43 sismomètres fond de mer (OBS) dans notre approche sismique passive et les composantes hydrophones de 16 sismomètres fond de mer pour l’approche sismique active. L’interférométrie de bruit ambiant et l’inversion de forme d’onde complète (FWI) des données de réfraction ont été utilisées pour imager les structures internes de la croûte et de la lithosphère. Grâce à la modélisation de l’interférométrie de bruit ambiant, on trouve une épaisseur moyenne de croûte de 7 km avec une couche peu profonde de faibles vitesses de cisaillement. De plus, nous en déduisons que les 2 km supérieurs sont très poreux et peuvent être fortement serpentinisés. La vitesse moyenne des ondes de cisaillement entre la base de la croûte et la profondeur maximale de notre modèle (15 km) est inférieure à la valeur de référence globale de 4.5 km/s et peut s’expliquer par le jeune âge des fonds marins de notre zone. Notre modèle bi-dimensionnel de vitesse des ondes P obtenu à partir de notre analyse FWI suggère des variations considérables de composition dans la partie supérieure le long du profil parallèle à l’axe. Notre étude propose un domaine de transition entre un domaine à prédominance volcanique et un non magmatique, entre ∼65 à 95 km de distance sur le profil. Des injections magmatiques dans des dikes sont proposées dans le domaine oriental non volcanique. Une augmentation vers l’ouest de l’apport de matériel magmatique est confirmée pour le mode d’accrétion océanique. Le modèle de vitesse des ondes P associé aux variations de serpentinisation suggère que le Moho est une transition graduelle d’une péridotite hydratéevers une péridotite non altérée
Ultra-slow spreading ridges are a new category of spreading ridges characterized by quasi-amagmatic crustal accretion, exposing considerable amounts of mantle derived peridotites on the seafloor. Investigating the contributions of tectonic, magmatic, and other involved processes is necessary to gain a comprehensive conceptual model of ultra-slow spreading ridges. Imaging the crustal and upper mantle structures can help us to understand the past and current geological activities in the ultra-slow spreading ridges. The aim of the project is to understand the oceanic crust formed in an ultra-slow spreading ridge called the Southwest Indian Ridge with a low melt supply. Our research project is based on the processing and modeling of the active and passive seismic data in the easternmost part of Southwest Indian Ridge. The data acquisition took place in 2014 during the SISMOSMOOTH cruise. We analyzed vertical component recordings from 43 ocean-bottom seismometers in our passive seismic approach and the hydrophone components of 16 ocean-bottom seismometers in the active seismic approach. Ambient-noise interferometry and full-waveform inversion (FWI) of refraction data were used to image the internal structures of the lithosphere. In the modeling of ambient-noise interferometry, we find an average crustal thickness of 7 km with a shallow layer of low shear velocities. Moreover, we infer that the uppermost 2 km are highly porous and may be strongly serpentinized. The average shear wave velocity between the base of the crust and the maximum depth of our model (15 km) was less than the global reference value of 4.5 km/s and was explained by the younger age of the seafloor in our area. Our two-dimensional P-wave velocity model obtained from FWI suggests considerable variations in the upper lithospheric compositions along the axis-parallel profile. A transition is expected at a distance of ∼65-95 km along the profile from the predominantly volcanic domain in the western zone to variable serpentinized peridotite in the eastern zone. Dike injections are predicted in this area. A westward increase in melt supply is proposed in the seafloor accretion mode. The serpentinization and P-wave velocity model suggests that the Moho is a gradual transition from hydrated to unaltered peridotite

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Anselme, Brice. "Contribution de l'imagerie satellitaire visible, proche infrarouge et infrarouge thermique, à l'étude des mers arctiques eurasiatiques." Phd thesis, Paris 4, 1997. https://tel.archives-ouvertes.fr/tel-00955324.

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Notre travail avait pour objectif d'apporter une contribution à l'amélioration des connaissances de l'environnement marin arctique. Plus précisément, nous nous sommes intéressés à l'étude des structures océaniques de surface, à la fois biologiques et physiques, dans les mers de Barents et de Kara, ainsi que dans la partie sud-est de la mer de Barents, à partir de l'imagerie spatiale opérant dans le domaine du visible, du proche infrarouge et de l'infrarouge thermique. Des mesures in situ nous ont permis de valider les algorithmes utilisés pour le traitement des images et de nous guider pour l'interprétation de celles-ci. Nous avons montré quelles étaient les zones apparemment les plus productives sur le plan de la production primaire et à quelle période de l'année se produisait l'efflorescence phytoplanctonique. Nous avons aussi mis en évidence les principaux fronts thermiques et hydrologiques, les directions suivies par les glaces de mer, leur relation avec les courants de surface, ainsi que le transport des sédiments et des polluants au débouché des fleuves sibériens. L'objectif sous-jacent à notre travail était de déterminer quelles étaient les régions les plus sensibles et les plus exposées à une éventuelle pollution du milieu marin. Au terme de ce travail, nous constatons que deux régions sont particulièrement vulnérables. Au nord de la mer de Barents, la zone de la lisière des glaces abrite un écosystème particulièrement important pour l'ensemble de la chaine alimentaire arctique ; une quelconque pollution dans cette région pourrait, selon son occurrence, avoir des conséquences désastreuses, en raison de l'intensité et de la brièveté de la floraison phytoplanctonique. La partie sud-est de la mer de Barents, qui abrite elle aussi de nombreuses espèces animales, et où circulent des masses d'eau et des glaces potentiellement contaminées, constitue la deuxième zone à risques. Il serait donc souhaitable de porter les efforts de recherche sur l'étude de ces deux régions, qui, outre leur richesses biologique, suscitent des intérêts croissants de la part des compagnies pétrolières en raison des réserves importantes du sous-sol en hydrocarbures et gaz naturel
The overall objective of our work was to improve the knowledge of the arctic marine environment. Using satellite remote sensing operating in the visible, near infrared and thermal infrared, we studied oceanic surface structures over the Barents and Kara seas, as well as in the southern part of the Barents sea. In situ measurements obtained from oceanographic campaigns allowed us to validate the algorithms we used for image processing and helped us in analyzing the images. We studied both biological and physical oceanic structures. Concerning primary production, we showed in which areas and when phytoplanktonic bloom start to develop. We also emphasized the areas where thermal and hydrological fronts appear, sea ice drift and its relationship to surface currents, as well as the transport of sediments and associated pollutants by rivers and their outflow distribution patterns into the sea. The final goal of our work was to outline which areas of the eurasiatic arctic seas are the most sensitive and exposed if a pollution should occur. We finally concluded that two areas were particularly vulnerable: the marginal sea ice zone in the northern Barents sea that supports large part of the phytoplanktonic ecosystem, source of the food chain. Due to the intensity and very short timing of the phytoplanktonic bloom in that area, a pollution could have serious consequences there. Important exchange of water masses and ice, potentially contaminated, occur in the southeastern part of the Barents sea, which constitute a large refuge for marine mammals and migratory birds. Concerns about oil and natural gas exploitation should lead future investigations to focus on monitoring of both areas

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Burchell, Mark Anthony. "An anthropological exploration of discipline and ritual practices among the Royal Marines." Thesis, University of Bristol, 2011. http://hdl.handle.net/1983/19864216-5e2d-4c4a-a68c-f60e64df7bc5.

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Despite the ever-growing number of publications on Military matters, in-depth studies of its unique cultural practices are still scarce due to their well-kept high perimeter fences. The author, a former Royal Marine, was able to return to the Commando Training Centre at Lympstone as an anthropologist to carry out participant observation, following an intake of recruits throughout their gruelling year-long training programme. Focus is on enculturation of the Marine recruits during their training, giving particular attention on the intricate mechanisms that transform them from ordinary civilian men into members of what is often regarded as the world's finest elite Commando unit. The ethnography presented in this thesis will provide a key to understanding the complex processes of Military enculturation through a close look at the relationships between disciplinary and punishment practices; violence and masculinity; narratives and personhood; and will explore how these issues become known to the recruits through their practical application of body to physical labour. This thesis represents an attempt to present the so far unexplored social experience of Royal Marines training culture.

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Saulnier, Ségolène. "Exploration des compositions isotopiques en magnésium des carbonates marins comme traceurs paléoenvironnementaux." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0267/document.

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L'utilisation des compositions isotopiques en Mg des carbonates marins peut permettre l'étude du cycle biogéochimique de cet élément. Ainsi, les carbonates sont susceptibles d'enregistrer la composition isotopique de Mg de l'océan lors de leur précipitation. Cependant, il est nécessaire de comprendre les facteurs environnementaux (e.g. température, pH, Mg/Ca de la solution) qui peuvent contrôler ces compositions. Le premier objectif de cette thèse a donc été de déterminer les paramètres pouvant impacter les compositions isotopiques de Mg des carbonates par des précipitations expérimentales en conditions contrôlées. Il a ainsi été mis en évidence, dans les gammes considérées, mais qui restent restreintes, l'absence de contrôle de la température, du pH et du Mg/Ca de la solution sur le fractionnement isotopique du Mg lors de la précipitation des carbonates. Le fractionnement isotopique du Mg entre la solution et la calcite, à l'équilibre, a été évalué à -2,13 ± 0,24 pour mille (2sigma) à partir de cette étude, combinée à des données de la littérature. Ces résultats ont ensuite été appliqués à l'étude des compositions isotopiques de Mg dans des coquilles de brachiopodes à la fois modernes et anciens. Pour cela, une quantification des effets vitaux vis-à-vis des isotopes du Mg lors de la croissance du brachiopodes a été réalisée. Ainsi, les zones en équilibre isotopique pour Mg, O et C et donc susceptibles d'être utilisables lors des reconstructions paléoenvironnementales sont situées au sein de la calcite interne sur les bords de la coquille. Les premières mesures des compositions isotopiques de Mg sur les derniers 60 Ma suggèrent des variations de la composition isotopique du Mg de l'océan qui pourraient être liées à un changement du flux de carbonate à l'océan
Studying the Mg isotopic composition in marine carbonate can help to understand the biogeochemical cycle of this element. Indeed, carbonates may record seawater Mg isotopic composition during their precipitation. However, it is necessary to understand the possible control of some environmental factors (e.g. temperature, pH, Mg/Ca of the solution) on those compositions. Therefore, the first goal of this thesis was to determine parameters impacting carbonate Mg isotopic composition with experimental precipitations under controlled conditions. Thus, it has been shown, in restricted ranges, that temperature, pH and solution Mg/Ca have no influence on Mg isotopic fractionation during calcite precipitation. Equilibrium Mg isotopic fractionation between solution and calcite has been evaluated to -2.13 ± 0.24 per thousand (2sigma) from this study, combined with published data. These results were then applied to a study of Mg isotopic compositions in modern and past brachiopod shells. For this, a quantification of vital effects with respect to Mg isotopes during the brachiopod growth was realized. The zones in isotopic equilibrium for Mg, O and C, and thus susceptible to be used for paleoenvironnemental reconstruction, are in the inner calcite at the edge of the shell. The first measurements of Mg isotopic compositions for the last 60 Ma suggest variations of Mg isotopic compositions of the seawater which could be linked to changes of carbonate flux in the ocean

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Ahsan, Nasir. "Combining Exploration and Exploitation in Active Learning." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/10144.

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This thesis investigates the active learning in the presence of model bias. State of the art approaches advocate combining exploration and exploitation in active learning. However, they suffer from premature exploitation or unnecessary exploration in the later stages of learning. We propose to combine exploration and exploitation in active learning by discarding instances outside a sampling window that is centered around the estimated decision boundary and uniformly draw sample from this window. Initially the window spans the entire feature space and is gradually constricted, where the rate of constriction models the exploration-exploitation tradeoff. The desired effect of this approach (CExp) is that we get an increasing sampling density in informative regions as active learning progresses, resulting in a continuous and natural transition from exploration to exploitation, limiting both premature exploitation and unnecessary exploration. We show that our approach outperforms state of the art on real world multiclass datasets. We also extend our approach to spatial mapping problems where the standard active learning assumption of uniform costs is violated. We show that we can take advantage of \emph{spatial continuity} in the data by geographically partitioning the instances in the sampling window and choosing a single partition (region) for sampling, as opposed to taking a random sample from the entire window, resulting in a novel spatial active learning algorithm that combines exploration and exploitation. We demonstrate that our approach (CExp-Spatial) can generate cost-effective sampling trajectories over baseline sampling methods. Finally, we present the real world problem of mapping benthic habitats where bathymetry derived features are typically not strong enough to discriminate the fine details between classes identified from high-resolution imagery, increasing the possiblity of model bias in active learning. We demonstrate, under such conditions, that CExp outperforms state of the art and that CExp-Spatial can generate more cost-effective sampling trajectories for an Autonomous Underwater Vehicle in contrast to baseline sampling strategies.

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Pajak, Dominik. "Algorithms for Deterministic Parallel Graph Exploration." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2014. http://tel.archives-ouvertes.fr/tel-01064992.

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Nous étudions dans cette thèse le problème de l'exploration parallèle d'un graphe à l'aide des multiples, synchronisés et mobiles agents. Chaque agent est une entité individuelle qui peut, indépendamment des autres agents, visitez les sommets du graphe ou parcourir ses arêtes. Le but de ensemble des agents est de visiter tous les sommets de graphe. Nous étudions d'abord l'exploration du graphe dans un modèle où chaque agent est équipé de mémoire interne, mais les nœuds n'ont pas de mémoire. Dans ce modèle les agents sont autorisés à communiquer entre eux en échangeant des messages. Nous présentons des algorithmes qui s'exécutent dans un minimum de temps possible pour polynomiale nombre d'agents (polynomiale en nombre de sommets du graphe). Nous étudions aussi quelle est l'impacte de différent méthodes des communications. Nous étudions des algorithmes où les agents peuvent se communiquer à distance arbitraire, mais aussi où communication est possible seulement entre les agents situés dans le même sommet. Dans les deux cas nous présentons des algorithmes efficaces. Nous avons aussi obtenu des limites inférieures qui correspondent bien à la performance des algorithmes. Nous considérons également l'exploration de graphe en supposant que les mouvements des agents sont déterminés par le soi-disant rotor-router mécanisme. Du point de vue d'un sommet fixé, le rotor- router envoie des agents qui visitent les sommet voisins dans un mode round-robin. Nous étudions l'accélération défini comme la proportion entre le pire des cas de l'exploration d'un agent unique et des plusieurs agents. Pour générales graphes, nous montrerons que le gain de vitesse en cas de multi-agent rotor-router est toujours entre fonction logarithmique et linéaire du nombre d'agents. Nous présentons également des résultats optimaux sur l'accélération de multi-agent rotor-router pour cycles, expanseurs, graphes aléatoires, cliques, tores de dimension fixé et une analyse presque optimale pour hypercubes. Finalement nous considérons l'exploration sans collision, où chaque agent doit explorer le graphe de manière indépendante avec la contrainte supplémentaire que deux agents ne peuvent pas occuper le même sommet. Dans le cas où les agents sont donnés le plan de graphe, on présente un algorithme optimal pour les arbres et un algorithme asymptotiquement optimal pour générales graphes. Nous présentons aussi des algorithmes dans le cas de l'exploration sans collision des arbres et des générales graphes dans la situation où les agents ne connaissent pas le graphe. Nous fermons la thèse par des observations finales et une discussion de problèmes ouverts liés dans le domaine de l'exploration des graphes.

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Chevanne, Isabelle. "Les journaux sanitaires de l'expédition en Terre Adélie (1837-1840)." Nantes, 1994. http://www.theses.fr/1994NANT005P.

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Poitelon, Yannick. "Explorations de modèles animaux et cellulaires de la maladie de Charcot-Marie-Tooth de type AR-CMT2A." Aix-Marseille 2, 2009. http://www.theses.fr/2009AIX20710.

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Rajendran, Aravind. "Noise Margin, Critical Charge and Power-Delay Tradeoffs for SRAM Design Space Exploration." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1307667225.

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Avanthey, Loïca. "Acquisition et reconstruction de données 3D denses sous-marines en eau peu profonde par des robots d'exploration." Thesis, Paris, ENST, 2016. http://www.theses.fr/2016ENST0055/document.

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Notre planète est pour l’essentiel recouverte par les mers et les océans, or notre connaissance des fonds marins est très inférieure à celle que nous possédons sur les terres émergées. Dans ce mémoire, nous cherchons à concevoir un système dédié à la cartographie thématique à grande échelle pour obtenir à la demande un nuage de points dense représentatif d’une scène sous-marine ou subaquatique par reconstruction tridimensionnelle. Le caractère complexe de ce type de système nous amène à privilégier une approche délibérément transversale. Nous nous intéresserons en particulier aux problématiques posées par l’étude à l’échelle des individus de petites zones en eau peu profonde. Les premières concernent l’acquisition in situ efficace de couples stéréoscopiques avec une logistique adaptée à la taille des zones observées : nous proposons pour cela un microsystème agile, peu coûteux et suffisamment automatisé pour fournir des données reproductibles et comparables. Les secondes portent sur l’extraction fiable de l’information tridimensionnelle à partir des données acquises : nous exposons les algorithmes que nous avons élaborés pour prendre en compte les caractéristiques particulières du milieu aquatique (dynamisme, propagation difficile des ondes électromagnétiques, etc.). Nous abordons donc en détail dans ce mémoire les problèmes d’appariement dense, d’étalonnage, d’acquisition in situ, de recalage et de redondance des données rencontrés dans le milieu sous-marin
Our planet is mostly covered by seas and oceans. However, our knowledge of the seabed is far more restricted than that of land surface. In this thesis, we seek to develop a system dedicated to precise thematic mapping to obtain a dense point cloud of an underwater area on demand by using three-dimensional reconstruction. The complex nature of this type of system leads us to favor a multidisciplinary approach. We will examine in particular the issues raised by studying small shallow water areas on the scale of individual objects. The first problems concern the effective in situ acquisition of stereo pairs with logistics adapted to the sizes of the observed areas: for this, we propose an agile, affordable microsystem which is sufficiently automated to provide reproducible and comparable data. The second set of problems relates to the reliable extraction of three-dimensional information from the acquired data: we outline the algorithms we have developed to take into account the particular characteristics of the aquatic environment (such as its dynamics or its light absorption). We therefore discuss in detail the issues encountered in the underwater environment concerning dense matching, calibration, in situ acquisition, data registration and redundancy

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Garand, Marie. "La pratique du graphisme d'auteur par le roman graphique - Exploration de l'identité féminine." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/27980/27980.pdf.

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40

Reynisson, Reynir Fjalar. "Deep structure and sub-basalt exploration of the mid-Norwegian margin with emphasis on the Møre margin." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11136.

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This thesis addresses the use of potential field data in two main topics: sub-basalt exploration and structure of the deeper crust. Synthetic models and forward models of the Møre margin were constructed to test the sensitivity of the various potential field methods. The synthetic models demonstrate that forward modelling of the gravity and magnetic data is a valuable tool in basement recognition in sub-basaltic settings and the use of gravity gradients further limits the modelling ambiguity and improves the basement mapping. Deep sills, as observed in the Møre Basin, cannot be identified from the gravity and magnetic data alone but the lava flows have a clear effect on the gravity and magnetic signature if thicker than ~1 km. Experiments with Euler Deconvolution reveal the limitations of the method in sub-basaltic settings. A 3D regional gravity and magnetic model of the Møre margin integrated with seismic and well data gives a novel view on the architecture of the continental crust, the distribution of high density lower crust, and the Moho topography. The isostatic response of the water and sediment loading reflected by the Moho provides further insight in the evolution of the margin. The results from the Møre margin model merged with results from a 3D model of the Vøring and Lofoten margins give a regional view on the deep structures on the mid-Norwegian margin. Combination of the modelling results and isostatic considerations provide means to address the origin of the lower crustal body on the margin and the evolution of the whole mid-Norwegian margin.

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Rabl, Verena Marina [Verfasser], and Christoph [Akademischer Betreuer] Wiese. "Notfallmedizinische Versorgung palliativmedizinisch orientierter Akutsituationen in Deutschland – eine explorative Befragung Ärztlicher Leiter Rettungsdienst / Verena Marina Rabl. Betreuer: Christoph Wiese." Regensburg : Universitätsbibliothek Regensburg, 2014. http://d-nb.info/1059570203/34.

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Avanthey, Loïca. "Acquisition et reconstruction de données 3D denses sous-marines en eau peu profonde par des robots d'exploration." Electronic Thesis or Diss., Paris, ENST, 2016. http://www.theses.fr/2016ENST0055.

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Notre planète est pour l’essentiel recouverte par les mers et les océans, or notre connaissance des fonds marins est très inférieure à celle que nous possédons sur les terres émergées. Dans ce mémoire, nous cherchons à concevoir un système dédié à la cartographie thématique à grande échelle pour obtenir à la demande un nuage de points dense représentatif d’une scène sous-marine ou subaquatique par reconstruction tridimensionnelle. Le caractère complexe de ce type de système nous amène à privilégier une approche délibérément transversale. Nous nous intéresserons en particulier aux problématiques posées par l’étude à l’échelle des individus de petites zones en eau peu profonde. Les premières concernent l’acquisition in situ efficace de couples stéréoscopiques avec une logistique adaptée à la taille des zones observées : nous proposons pour cela un microsystème agile, peu coûteux et suffisamment automatisé pour fournir des données reproductibles et comparables. Les secondes portent sur l’extraction fiable de l’information tridimensionnelle à partir des données acquises : nous exposons les algorithmes que nous avons élaborés pour prendre en compte les caractéristiques particulières du milieu aquatique (dynamisme, propagation difficile des ondes électromagnétiques, etc.). Nous abordons donc en détail dans ce mémoire les problèmes d’appariement dense, d’étalonnage, d’acquisition in situ, de recalage et de redondance des données rencontrés dans le milieu sous-marin
Our planet is mostly covered by seas and oceans. However, our knowledge of the seabed is far more restricted than that of land surface. In this thesis, we seek to develop a system dedicated to precise thematic mapping to obtain a dense point cloud of an underwater area on demand by using three-dimensional reconstruction. The complex nature of this type of system leads us to favor a multidisciplinary approach. We will examine in particular the issues raised by studying small shallow water areas on the scale of individual objects. The first problems concern the effective in situ acquisition of stereo pairs with logistics adapted to the sizes of the observed areas: for this, we propose an agile, affordable microsystem which is sufficiently automated to provide reproducible and comparable data. The second set of problems relates to the reliable extraction of three-dimensional information from the acquired data: we outline the algorithms we have developed to take into account the particular characteristics of the aquatic environment (such as its dynamics or its light absorption). We therefore discuss in detail the issues encountered in the underwater environment concerning dense matching, calibration, in situ acquisition, data registration and redundancy

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Simard, Mélissa. "Théâtre, culture et société haïtienne : une exploration interartistique et interculturelle de "La mort de soi dans sa longue robe de Mariée" de Guy Régis Jr." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29411/29411.pdf.

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Le présent essai propose un retour sur un processus de recherche-création entourant la mise en scène du texte La mort de soi dans sa longue robe de Mariée, de l'auteur haïtien exilé à Paris, Guy Régis Jr. La représentation théâtrale eut lieu en avril 2011, au LANTISS de l'Université Laval. Elle a réuni une équipe de création composée de comédiens et musiciens, amateurs et professionnels, d'origines brésilienne, centrafricaine, haïtienne et québécoise. La recherche entourant la réalisation de ce projet a été guidée par un besoin de réflexion sur un élément déterminant de la culture haïtienne, la mythologie vaudou comme inspiration du texte dramatique de La mort de soi dans sa longue robe de Mariée. L’analyse de la création est donc basée sur certaines études culturelles entourant le théâtre populaire haïtien, le théâtre rituel et le théâtre anthropologique. Dans un second temps, l'essai couvre la diffusion de la culture populaire et l'affirmation de l'identité (imaginaire collectif/ histoire) comme conditions essentielles de résistance contre le néo-colonialisme mondial et la globalisation culturelle. Finalement, l'essai se penche sur le métissage et la créolisation comme systèmes de communication interculturelle au théâtre.

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Prodan, Anca Claudia [Verfasser], Marie-Theres [Akademischer Betreuer] Albert, and Uwe [Akademischer Betreuer] Meinberg. "The digital "Memory of the World" : an exploration of documentary practices in the age of digital technology / Anca Claudia Prodan ; Marie-Theres Albert, Uwe Meinberg." Cottbus : BTU Cottbus - Senftenberg, 2014. http://d-nb.info/111428288X/34.

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Kervio, Gaëlle. "Effets de l'insuffisance cardiaque sur les adaptations cardiorespiratoires à l'exercice sous-maximal et exploration de leur régulation par l'étude du système nerveux autonome." Rennes 1, 2003. http://www.theses.fr/2003REN1B075.

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Les insuffisants cardiaques (IC) sont caractérisés par une intolérance à l'effort mise en évidence lors d'une épreuve d'effort limitée par les symptômes. Le test de marche de 6 minutes (TM6) avec mesure de la distance parcourue est généralement utilisé afin de compléter les résultats obtenus lors de l'épreuve d'effort. Notre objectif était d'évaluer l'influence de l'insuffisance cardiaque sur la reproductibilité et sur les paramètres cardiorespiratoires du TM6 et d'approfondir les mécanismes physiopathologiques en cause dans l'adaptation de la fréquence cardiaque (FC) des IC par l'étude de sa variabilité (VFC). L'enregistrement des paramètres métaboliques classiques lors de l'épreuve d'effort et du TM6 a été effectué par l'utilisation d'un appareil portabl e de mesure des échange gazeux (Cosmed K4, Rome, Italie). La VFC a été étudiée au repos allongé et lors de tests physiologiques : respiration contrôlée, orthostatisme et exercice sous-maximal. Les principaux résultats montrent une différence d'adaptation entre les sujets sains et les IC à tous les niveaux. En effet chez les sujets sains, après deux test de familiarisation, le TM6 correspond à un exercice sous-maximal modéré, avec atteinte d'un état stable des paramètres cardiorespiratoires. Lors de ce test, les données de FC sont supérieures l'après-midi. Au contraire chez les IC, le TM6 représente un effort sous-maximal intense, avec unique plafonnement de la consommation d'oxygène (V'O2). Une réalisation du TM6 l'après-midi entraîne des valeurs plus élevées de V' O2 et de FC. L'analyse des paramètres spectraux conventionnels de la VFC indique une meilleure modulation du nœud sinusal à l'activité nerveuse sympathique chez les sujets sains comparés aux IC traités par β-bloquants, alors que la modulation parasympathique est similaire entre les 2 populations. En conclusion le moment de réalisation du TM6 dans la journée dépend de la population et des paramètres étudiés. Il en est de même pour son intensité de réalisation. De plus, l'activité régulatrice du système nerveux autonome sur le nœud sinusal reste altérée chez les IC sous β-bloquants.

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Loudcher, Rabaseda Sabine. "Contributions à l'extraction automatique de connaissances : application à l'analyse clinique de la marche." Lyon 1, 1996. http://www.theses.fr/1996LYO10309.

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Dans cette these, notre objectif methodologique consiste a contribuer a la mise en place de nouvelles techniques d'extraction de connaissances a partir de donnees (ecd). Parmi les methodes d'ecd, nous nous interessons plus particulierement a celles basees sur les graphes d'induction. Notre contribution methodologique est double. D'une part, nous souhaitons proposer une methode d'ecd capable de manipuler simultanement des donnees numeriques et symboliques. Notre contribution porte sur une meilleure prise en compte des donnees numeriques dans les graphes d'induction avec la constitution d'un nouvel algorithme de discretisation, baptise fusinter. Les resultats obtenus par fusinter sont compares a ceux obtenus par d'autres techniques. Nous discutons egalement de l'evaluation, avant toute discretisation, de la separabilite des exemples selon les classes, par le test non parametrique des sequences de a. Mood. D'autre part, pour alimenter la base de connaissances d'un systeme expert ou pour ameliorer la comprehension d'un probleme, nous souhaitons generer, a partir d'une methode d'ecd, des connaissances exprimees sous forme de regles claires et concises. Suite aux problemes engendres par cette generation, nous nous posons le probleme de la simplification d'une base de regles. En reponse aux limites des differentes approches de simplification, nous introduisons notre propre algorithme qui permet d'eliminer les informations redondantes et incoherentes pour obtenir une base optimale avec des regles en faible nombre et concises. Dans le cadre d'un projet medical, des medecins nous ont soumis un probleme concernant la caracterisation de la marche dans le but de la constitution d'un systeme d'identification automatique du type de marche. Notre objectif dans le cadre de cette application est de mettre en evidence les parametres de certaines boiteries. Nous posons comme hypothese que le deplacement du centre du bassin constitue un resume de la marche et est sensible a ses perturbations. Nous decrivons la trajectoire du centre du bassin par des parametres spatiaux et temporels. Parmi ces parametres descriptifs, nous souhaitons trouver ceux caracteristiques des differents types de marche. Ce projet comporte un probleme d'ecd avec la determination des regles de diagnostic des differents types de marche. Par consequent, nous utilisons comme methodes d'ecd, des methodes d'origine statistique, neuronale, genetique, symbolique ou a base de graphe d'induction. Une comparaison des resultats de ces methodes montre que les graphes d'induction, et notamment la methode sipina generalisee a l'aide de nos developpements theoriques, presentent un compromis satisfaisant entre les exigences d'explicabilite et d'efficacite. La methode sipina nous permet de mettre en evidence les parametres caracteristiques des differentes demarches. Des resultats interessants nous encouragent a valider les regles de diagnostic obtenues, avant de pouvoir mettre en place le systeme d'identification automatique.

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Branco, Emanuel Tairocas. "Acompanhamento técnico e elaboração do plano de lavra da Pedreira Texugo, da Empresa Lugramar, Lda." Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/15473.

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No presente documento são descritos todos os processos utilizados nos trabalhos de exploração da Pedreira Texugo, pertença da empresa Lugramar, Lda. Esta descrição tem como destaques principais as operações realizadas durante o ciclo de trabalhos de pedreira, as tarefas de desenvolvimento de pedreira e operacionalidade de todos os equipamentos utilizados na realização dos trabalhos. São ainda descritas as tarefas acompanhadas e realizadas pelo estagiário durante o período de permanência na empresa, bem como os trabalhos executados necessários à realização do Plano de Lavra da pedreira; ABSTRACT: Technical Monitoring and Quarry Management Plan Development of Texugo’s Quarry, Lugramar Company, Lda. In the present document are described all the processes used in the exploration of Texugo’s Quarry, belonging to Lugramar Company, Lda. As main highlights, this description intends to cover all the operations done during the quarrying cycle, the quarry development tasks, and the workability of all equipment used while performing said works. The tasks monitored and done by the intern during the internship period are also described, as well as the work required to achieve the Quarry Management Plan.

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Rouet, Gilles. "L'invention de l'école : étude statistique et cartographique diachronique des modèles scolaires et exploration d'un exemple régional : l'école primaire dans la Marne et les Ardennes sous la Monarchie de Juillet." Reims, 1990. http://www.theses.fr/1991REIML001.

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L’exploration de l'exemple du nord de la champagne illustre l'étude diachronique des éléments constitutifs, repérés et repérables, du système polymorphe de scolarisation primaire entre 1820 et 1876. Les pratiques scolaires, sous la monarchie de juillet, restent disparates sur le territoire français mais les manifestations de certaines demandes sociales d'instruction ou de surveillance favorisent l'invention d'un système cohérent dans ses représentations comme dans sa réalité projetée. La loi Guizot accélère cette évolution, au moins dans une partie de la France, anticipant sur l'obligation scolaire et amorçant la fonctionnarisation des instituteurs. La raison universelle fonde cette loi du 28 juin 1833, dont l'enjeu est le maintien de l'ordre social et la formation d'une citoyenneté. A une fonction particulière, organisée a la fois grâce a cette politique décidée et conciliante et a la volonté des acteurs locaux, s'associe un cadre particulier, un espace, un temps, un rythme, des objets. Apparait alors une nouvelle génération d'instituteurs, professionnels, formes, qui se notabilisent au sein des communautés. La gestion des locaux scolaires leur échappe, et ils peuvent s'interes ser beaucoup plus aux aspects pédagogiques de l'instruction primaire. L'invention de l'école, espace collectif d'hygienisation exemplaire, témoigne également de la reconnaissance du statut de l'enfance, période consacrée a l'apprentissage du savoir et de la vie sociale. Les comites supérieurs et locaux ont un rôle fondamentale dans la généralisation idéologique et pratique du système. Disparaissant en même temps que le régime politique, ils ont permis l'instauration d'un contrôle centralise sur la scolarisation élémentaire. L'ecole est devenue un apparel d’état
The examination of the example of the north of the champagne illustrates the evolutionary study of the constituent elements, noted and recognized, of the polymorphic system of elementary education between 1820 and 1876. The scholastic practices, under the "monarchie de juillet", remained dissimilar on french territory but the manifestatio of certain social demands for instruction or surveillance favoured the invention of a coherent system in its representations as in its projected reality. The guizot law accelerated this evolution, at least in part of france, anticipating obligatory scholastic attendance and compulsory way for the incorporation of teachers into the civil service system. The "raison universelle", the purpose of which was the maintenance of social order and the formation of a citizenship, founded this law on 28 june 1833. To a particulat function, organized both thanks to a determined and concilatory policy and the desires of the local actors, is associated a particular framework, space, time, rythm and obhects. Thus appeared a new generation of teachers and trained professionals who distinguished themselves in the bosom of the communities. This administration of the school premises was removed from their control and they could interest themselves much more in the pedagogic aspects of primary instruction. The invention of school, a collective space of examplary sanitation, testifies to the recognition of the status of childhood, a period devoted to the apprentice ship of knowledg and social living. The "comites locaux et superieurs" had a fundamental role in the ideological generalization and application of the system. Disapearing at the same time as the political regime, they permited the establishment oc a centralised control of elementary education. The school thus becam a state apparatus

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De, Haas Anaïs. "Tenir les mondes à distance : sémiotique de la "découverte", à partir des journaux des marins de la circumnavigation de Bougainville (1766-1769)." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEH192.

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Entre 1766 et 1769, sur l'Étoile et la Boudeuse, plus de trois cents hommes – et une femme déguisée en homme – ont fait le tour du monde. Il s'agissait d'un des premiers "voyage de découverte", et six marins ont tenu des journaux de bord. Cette thèse propose d'étudier ces journaux, d'analyser les procédés discursifs mis en œuvre dans les descriptions et récits des interactions avec les gens que les marins ont rencontrés lors des escales, là où il s'agissait des 'premiers contacts'. J'étudie d'abord les récits des escales dans le détroit de Magellan, puis, surtout, les récits de l'escale à Tahiti, où les Tahitiens et Tahitiennes ont accueilli les navigateurs d'une manière singulière: ils et elles leur offraient de la nourriture et des boisons en abondance, les invitaient dans leur maisons, et faisaient comprendre aux marins qu'on attendait d'eux qu'ils fassent l'amour avec les femmes tahitiennes... L'irruption des femmes et des corps au premier plan de la rencontre perturbe les marins, bouleverse leurs récits, et permet de mieux saisir – grâce à ce trouble, grâce à ces intrusions qui perturbent le programme scientifique – certains aspects du projet de 'découverte'. J'analyse aussi les interprétations qui ont été faite de ces récits de l'escale à Tahiti, depuis les savants du 18ème siècle jusqu'aux anthropologues du 21ème siècle
Between 1766 and 1769, on the Étoile and the Boudeuse, more than three hundred men – and one woman dressed up as a man – sailed around the world. It was one of the first « discovery voyages ». Six of the sailors held logbooks. This thesis offers a study of these logbooks, in order to analyse the discursive processes at work in the descriptions and narrations of the first contacts between the sailors and the people they had met during their stopovers. I begin with a study of the narratives of the stopovers in the Strait of Magellan, and continue with the narratives of the stopover at Tahiti. There, Tahitian men and women welcomed the sailors in a particular way : they offered them food and drink in abundance, invited them into their houses, and suggested to the sailors that they were expected to make love with Tahitian women… The irruption of women and bodies at the foreground of the encounter disrupts the navigators, disrupts their narratives and allows for a better understanding of certain aspects of the « discovering » project – thanks to this disorder, thanks to these intrusions that disrupt the scientific programm. I also analyse the interpretations of theses narratives of the stopover at Tahiti, from the savants of the 18th century until the anthropologists of the 21 century

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Hempel, Antje Marie [Verfasser]. "Altersspezifische Prognosefaktoren für das Überleben bei älteren Patientinnen (>70 Jahre) mit fortgeschrittenem Ovarialkarzinom unter Platin-Taxanhaltiger Chemotherapie: eine kombinierte explorative Analyse von drei multizentrischen prospektiv randomisierten Phase III Studien der AGO-OVAR / Antje Marie Hempel." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/1044576154/34.

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Dissertations / Theses on the topic 'Marine exploration'

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