Tesi sul tema "Hypoxie marine"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-30 saggi (tesi di laurea o di dottorato) per l'attività di ricerca sul tema "Hypoxie marine".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi le tesi di molte aree scientifiche e compila una bibliografia corretta.
Vanderplancke, Gwenaëlle. "Conséquences à long terme d'une exposition précose à l'hypoxie sur la physiologie du bar européen (Dicentrarchus labrax) et de la sole commune (Solea solea)". Thesis, Brest, 2015. http://www.theses.fr/2015BRES0006/document.
The dissolved oxygen in seawater has steadily declined in many coastal marine ecosystems in the last 50 years because of global warming and increasing coastal human activities. This decrease in oxygen in seawater causes episodes of hypoxia increasingly frequent and severe in coastal and estuarine areas. Some organisms may escape these environmental constraints by migration or dispersion. Others, with limited swimming capabilities must implement physiological regulation (phenotypic plasticity) to enable them to adapt and survive. This is particularly the case of marine fish larvae that are likely to be present in coastal nursery at the end of their development. It is now well established that the regulations implemented by organisms to cope with their environment during the early stages of life can imprint their physiological function in the long-term and change their life trajectory. While much information on early conditioning is available in the field of medicine, knowledge of these effects in marine organisms in an ecological context are still very fragmentary. Therefore, the main objective of this thesis was to evaluate the physiological consequences, not only in the short-term but especially in the long-term, of an exposition to a moderate hypoxia (8 days, 40% air saturation) of marine fish at the end of larval development. Another originality of this work was based on the comparison of adaptive responses implemented in two species, one pelagic ─ European sea bass (Dicentrarchus labrax) ─ and one benthic ─ the common sole (Solea solea). Our results have allowed us to show a significant long-term effect of early hypoxic stress on the physiological performance of juvenile and especially their growth. Juveniles of European sea bass and juveniles of common sole have, respectively, lower and higher growth after being exposed to a hypoxic environment in the larval stage. The negative effect on growth observed in sea bass was due, in part, to lower energy assimilation as a consequence of an impact on the digestive function. Moreover, molecular analyzes in the liver of sea bass juveniles indicate an impregnation at the transcriptional level of the expression of genes involved in the response to hypoxia. The positive effect observed on the growth of sole juveniles is associated with better tolerance to thermal and hypoxic stress and a decrease in metabolic scope. The results obtained in European sea bass and common sole suggest that changes in energy allocations could explain the physiological performances observed in the long-term. Globally, all the data obtained in this thesis underline the importance of the environmental parameters encountered by fish during their young life stages on their future physiological performances. Such physiological impregnation by the early environment is species-specific, revealing potential different adaptation strategies
李嵐 e Laam Li. "Effects of hypoxia on marine benthic communities : from bacteria to invertebrates". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/193402.
published_or_final_version
Biological Sciences
Master
Master of Philosophy
Nestlerode, Janet A. "Effects of Periodic Environmental Hypoxia on Predator Utilization of Macrobenthic Infauna". W&M ScholarWorks, 1996. https://scholarworks.wm.edu/etd/1539617700.
Artigaud, Sébastien. "Approche intégrative de la réponse d'un organisme marin face au changement climatique : la coquille Saint-Jacques Pecten maximus et les stress thermique et hypoxique". Thesis, Brest, 2013. http://www.theses.fr/2013BRES0078/document.
Coasts are among the most vulnerable ecosystems to the ongoing global changes, which result in increased water temperatures and frequencies of hypoxic episodes. The great scallop, Pecten maximus, is a subtidal species living at depths of 2-210 m. In spite of its commercial and major ecological values, only few studies at the molecular level were performed on this species. This thesis aimed at characterizing the molecular mechanisms implied in acclimation of this species to thermal and hypoxia stresses. We first characterized the changes of expression of the genes / proteins in response to a long-term thermal stress (56 days), by using both a transcriptomic- (RNAseq) and a proteomic- (2-DE based) approaches, in the mantle tissue of scallops. This allowed us to identify key regulatory pathways (eg., AP-1), the major functions (eg., cytoskeleton) and processes (eg., apoptosis) involved in the response, but also to observe the main orientations of metabolism (eg., degradation of lipid reserves). The response of organisms to hypoxia depends on how they cope with low oxygen availability. Therefore, we first carried out a comparative approach with an intertidal species, the mussel (Mytilus spp.) to characterize the physiological response of P. maximus to hypoxia. Of note, we could determine its oxyregulatory parameters, particularly its critical point in 02 (Pc02). Then, coupling the effects of temperature and of hypoxia, we developed a proteomic approach that allowed us to identify several proteins (CK2, GLN, etc.) potentially involved in the response at the molecular level. Finally, in an effort to better understand the particular physiology of these mollusks in their natural environment, we compared the proteomic signatures of two populations of P. maximus living in highly contrasted ecosystems, ie in the northern limit- (Norway) and the center- (Brest) of the biogeographical distribution of this species. The results suggest major differences between the two populations, especially at the cytoskeleton level. In all, this work opens new avenues for understanding the molecular mechanisms governing the adaptation of mollusks to heat and hypoxia, two stresses that will most probably greatly influence the lifestyle of marine organisms and populations in future years
Da, Fei. "Impacts of Atmospheric Nitrogen Deposition and Coastal Nitrogen Fluxes on Chesapeake Bay Hypoxia". W&M ScholarWorks, 2018. https://scholarworks.wm.edu/etd/1530192498.
Ogino, Tetsuya. "Environmental adaptation mechanism in marine annelids". Kyoto University, 2019. http://hdl.handle.net/2433/242707.
0048
新制・課程博士
博士(農学)
甲第21830号
農博第2343号
新制||農||1068(附属図書館)
学位論文||H31||N5202(農学部図書室)
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 佐藤 健司, 教授 澤山 茂樹, 准教授 豊原 治彦
学位規則第4条第1項該当
Damerval, Marc. "Identification et rôle physiologique des inclusions contenues dans le système nerveux central de la moule Mytilus edulis et de la crépidule Crepidula fornicata". Caen, 1985. http://www.theses.fr/1985CAEN2004.
Morell, Alaia. "Dynamiques éco-évolutives des espèces exploitées en Mer du Nord en réponse à des variations biotiques et abiotiques de l'environnement". Electronic Thesis or Diss., Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILR079.
Global change scenarios are valuable for guiding management and governance strategies, stimulating decision making, and increasing collective awareness of future biodiversity trends. The degree of realism and integration of ecosystem models used for this purpose is constantly improving, but they still often neglect the evolution of marine populations in future projections. However, marine populations adapt to global changes, either through phenotypic plasticity or evolution, through modifications of their biological characteristics such as life history traits, physiological and bioenergetic traits. The challenge of this thesis is to develop an ecosystem model that allows the exploration of biodiversity scenarios at intra- and inter-specific scales by explicitly representing the phenotypic plasticity of life history traits, their genetic variability, selection and evolution under the combined influence of fisheries and climate change, and the resulting genetic drift and loss of genetic diversity. Applied to the North Sea, this new model is used to understand the processes responsible for changes in life history traits, whether they are of plastic or evolutionary origin. On the one hand, the bioenergetic processes underlying plastic changes are studied by an original approach comparing the differences between the fundamental and realized thermal response curves for different species and life history stages. On the other hand, changes in life history traits are explored through an evolutionary lens by taking into account multiple selection pressures such as fishing, prey-predator interactions and climate change.The integration of plastic and evolutionary processes in ecosystem models allows to describe the inter-individual variability of biological traits and to understand their temporal trends observed in the marine environment. In this way, it responds to the crucial issue of credibility of intra- and inter-specific biodiversity projections under scenarios combining climate and fisheries. The integration of these processes will also allow to quantify more precisely the synergistic and antagonistic effects of these two pressures and to take into account the capacity of populations to adapt to global changes in order to estimate more reliably their resilience
Plante, Audrey. "Marine benthic hypoxia and its consequences for sediment-water exchanges and early diagenesis". Doctoral thesis, Universite Libre de Bruxelles, 2020. https://dipot.ulb.ac.be/dspace/bitstream/2013/312521/4/Thesis.pdf.
Le plateau continental du Nord-Ouest de la Mer Noire subit une hypoxie saisonnière. L'environnement benthique, l'échange à l'interface eau-sédiment et les réactions diagénétiques sont influencés par ce phénomène. Dans le cadre du projet BENTHOX, deux campagnes de prélèvement ont été menées sur le plateau au printemps 2016 et à l'été 2017 dans le but de comprendre ces changements.La première partie de cette recherche concerne l’impact des faibles concentrations en oxygène dans les eaux de fond sur les réactions diagénétiques. Les micro-profils de paramètres géochimiques et les mesures de flux ont montré des variabilités spatiales et temporelles dans le compartiment benthique pour les deux saisons étudiées. Les zones les plus proches des côtes ont présenté les flux les plus importants de consommation d'oxygène et de sulfate. Ces régions ont été fortement influencées par les apports fluviaux induisant une productivité plus élevée et entraînant à son tour une augmentation des flux de matière organique déposée sur le fond marin. Les réactions diagénétiques sont affectées par la désoxygénation saisonnière des eaux de fond. La respiration oxique etait moins importante en été comme en témoigne la profondeur de pénétration moins profonde de l’oxygène. Depuis 1995, l’absorption d’oxygène dissous (DOU) rapportée pendant la période limitée en oxygène a indiqué que la concentration d'oxygène dissous jouait un rôle important dans les flux d'échanges benthiques. De plus, une diminution de la profondeur à laquelle la réduction des sulfates et la réduction des oxydes métalliques témoigne de l'impact d'une faible concentration en oxygène sur la cascade diagénétique. En conséquence, la minéralisation benthique de la matière organique a été affectée. Au cours de l'été 2017, la minéralisation oxique du carbone a été moins importante et la contribution des espèces réductrices à la consommation d’oxygène a augmenté. La respiration anaérobie de la matière organique est ainsi devenue le processus dominant pendant la période d'hypoxie.La deuxième partie portait sur l'étude du cycle du soufre et du fer dans les sédiments du plateau lors de l'événement de faible teneur en oxygène de l'été 2017. Les sédiments de la station proche de l'embouchure du Danube et de celle du Dniepr présentaient une signature de matière détritique différente de celle de la croûte supérieure. Les apports de matière organique, notamment transportés par les rivières, pourraient influencer le signal. Les sédiments du plateau nord-ouest étudiés étaient cependant d'origine marine. Suite à la réduction du sulfate déjà observée et mentionnée ci-dessus, les sulfures d'hydrogène produits ont été rapidement consommés comme le suggèrent les faibles concentrations en sulfure acide volatil (AVS) et en sulfure dissous. La présence de pyrite dans les couches supérieures des sédiments près de l'interface eau-sédiment était plausible car la formation de pyrite dans la colonne d'eau avait été signalée en raison de la résistance plus élevée de la pyrite à l'oxydation par rapport à l'AVS (Wijsman et al. 2001). Un dépôt à l'état non stationnaire a été observé comme le suggèrent Wijsman et al. (1999). Elle a été caractérisée par une chute brutale de la teneur en pyrite causée peut-être par des fluctuations de salinité, des concentrations d'O2 dissous et des flux de matière organiqueLe fer non réactif constituait la fraction principale du fer total présent dans les sédiments. Sa contribution est tombée dans la gamme signalée pour les sédiments marins des marges continentales. Une variation spatiale de la concentration en fer hautement réactif a néanmoins été observée. Près de l'embouchure du Dniepr, les teneurs en fer réactif étaient plus faibles et pouvaient être attribuées aux apports fluviaux moins importants, aux processus de sorption et / ou de précipitation ou encore à la réallocation du fer réactif des dépôts du plateau vers les sédiments en profondeur et eaux euxiniques.La dernière partie de cette thèse concerne la biogéochimie des métaux (Fe, Mn, Zn, Cu, Ni, Hg, Co et Cd) lors de la diagenèse précoce et l'évaluation de l'enrichissement et de la pollution de ces métaux dans les sédiments du plateau. Les résultats ont montré que les métaux traces sont probablement liés aux oxydes de fer et de manganèse ainsi qu'aux sulfures. Ni et Zn pourraient être impliqués dans l'adsorption et la coprécipitation avec les oxydes de Fe et de Mn. Le Cu semble être associé préférentiellement aux sulfures mais aucune corrélation claire n'a été trouvée. L'enrichissement et la pollution de ces métaux dans les sédiments du plateau ont montré une variabilité spatiale. La zone du delta du Danube a été enrichie en Ni, Cu et Zn tandis que la région d'Odessa s'est enrichie en Co et Cd. La pollution des sédiments du plateau allait de « non polluée » à « très fortement polluée ». Depuis la fin du 20e siècle, la teneur en métaux lourds des sédiments du plateau est restée stable dans la région d'Odessa mais a augmenté dans la région du delta du Danube.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Sagasti, Alessandra. "The role of stress in determining community structure: Effects of hypoxia on an estuarine epifaunal community". W&M ScholarWorks, 2000. https://scholarworks.wm.edu/etd/1539616839.
Long, William Christopher. "Hypoxia and Macoma balthica : ecological effects on a key infaunal benthic species /". W&M ScholarWorks, 2007. http://www.vims.edu/library/Theses/Long07.pdf.
Melrose, Donald Christopher. "Underway profiling of photosynthesis and dissolved oxygen in Narragansett Bay, RI /". View online ; access limited to URI, 2005. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3186913.
Lake, Samuel J. "Modeling the formation of periodic hypoxia in partially mixed estuaries and its response to oligotrophication and climate change". W&M ScholarWorks, 2013. https://scholarworks.wm.edu/etd/1539616727.
Watson, Jay L. "Collective action problems and cumulative effects : addressing pollution of marine waters in Hood Canal, Washington /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/5515.
Bonaglia, Stefano. "Control factors of the marine nitrogen cycle : The role of meiofauna, macrofauna, oxygen and aggregates". Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-115036.
At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.
Ho, Chun Ming. "Interactive effects of hypoxia and ocean acidification on biofilms and the subsequent effects on the larval settlement of the marine invertebrate Crepdiula onyx". HKBU Institutional Repository, 2018. https://repository.hkbu.edu.hk/etd_oa/498.
Cary, Brian S. "Hypoxia in Hood Canal using modern science and traditional ecological knowledge to enhance our understanding of a degraded ecosystem /". Online pdf file accessible through the World Wide Web, 2007. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Brian%20Cary%20thesis.pdf.
Fairchild, Lisa M. "The influence of stakeholder groups on the decision making process regarding the dead zone associated with the Mississippi river discharge". [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001052.
Rovera, Simona. "Effects of different hypoxia timing regimes on a transitional habitat's ( Pialassa Baiona, Ravenna, Italy) benthic community". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20566/.
Rommwatt, Maya. "The Impact of Hypoxia on the Louisiana Brown Shrimp Fishery and the Potential for the Public Trust Doctrine to Slow Nonpoint Source Pollution". Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19247.
Dasnon, Anaïs. "Estimation des populations d'oiseaux marins à nidification hypogée ou en habitats complexes : optimisation des méthodes dans les Terres Australes Françaises". Electronic Thesis or Diss., La Rochelle, 2023. http://www.theses.fr/2023LAROS027.
Facing the massive loss of biodiversity, it is crucial to increase our knowledge about populations in order to rapidly implement effective conservation measures. Seabirds are among the most threatened and little-known of all bird species. Many of their species nest in isolated territories, in burrows or in areas inaccessible to man. Traditional survey methods are mainly used to monitor seabird populations, but their effectiveness remains uncertain. In addition, new data acquisition and analysis tools offer new perspectives, but remain too untested.This thesis proposes, in the context of the Réserve naturelle nationale des Terres australes françaises, to explore the effectiveness of traditional methods for estimating the populations of two coastal-nesting species, to test bioacoustics as a new method for estimating burrowing seabirds populations, and to use count and demographic monitoring data from a declining population to test the effectiveness of implementing conservation measures.Traditional survey methods are the most robust and can be used effectively to estimate and monitor seabird populations. These methods can be supplemented by the use of new technologies, in particular bioacoustics for surveys of hypogean nesting species. The combination of these methods and a sound understanding of the biology and ecology of the species will enable them to be conserved effectively over the long term
Baillieul, Sébastien. "Syndrome d'apnées du sommeil et cerveau : une relation bidirectionnelle Continuous positive airway pressure improves gait control in severe obstructive sleep apnoea: A prospective study Hypoxic conditioning and the central nervous system: A new therapeutic opportunity for brain and spinal cord injuries?" Thesis, Université Grenoble Alpes, 2020. https://thares.univ-grenoble-alpes.fr/2020GRALS025.pdf.
The human brain is a perfect example of our dependence on oxygen. Brain physiological constraints render it vulnerable to hypoxia, such as encountered in environmental conditions (high altitude exposure) or pathological hypoxemic conditions. Among those pathological conditions, and due to its high prevalence in general population and the various levels of hypoxia resulting of the different degrees of severity of the pathology, obstructive sleep apnoea syndrome (OSAS) is a pathophysiological model of choice to investigate the detrimental effects of hypoxia on the brain. The cyclical, repeated episodes of apnoea and hypopnea during sleep that characterize OSAS result in intermittent hypoxia, sleep fragmentation and fluctuations in intrathoracic pressure, which are stressors that triggers mechanisms contributing to the initiation and progression of life-threatening cardiometabolic diseases, as well as several brain repercussions, such as cognitive impairment and stroke. This Thesis work explores the bidirectional relationship between sleep apnoea syndromes (SAS) and the brain. The first axis is focused on the neurocognitive consequences of OSAS through the lens of gait control. The neurocognitive signature of OSAS has been thoroughly investigated but recently, gait impairments have been highlighted in severe OSAS, with dose-response relationship between OSAS severity and the magnitude of gait impairments. As gait control relies at least partly on frontal lobe functions, it has been suggested that gait could represent a marker of OSAS brain repercussions. We investigated the effects of continuous positive airway pressure (CPAP) treatment on gait control, with contrasting results. In a first prospective controlled study, eight weeks of CPAP improved gait control in severe OSAS patients (Baillieul et al., 2018, Plos One). In order to validate those results and investigate the neurophysiological correlates of the link between gait control and OSAS, we conducted a randomized controlled trial which investigated the impact of an 8-week CPAP treatment compared to sham-CPAP on gait control in severe OSAS patients (Baillieul et al., 2020, Submitted). Contrary to our hypothesis, we found no improvement in gait control in the CPAP group and this result is substantiated by the absence of impact of CPAP on the determinants of gait control, further illustrating the complexity of the OSAS-neurocognitive relationship. The second axis is focused on the cerebrovascular repercussions of SAS. SAS and stroke are both severe intertwined conditions, SAS being both cause and potentially consequence of stroke. The present work is focused on the identification of phenotypic traits of SAS in post-stroke patients, to improve diagnosis of SAS following stroke (Baillieul et al., in preparation). Screening stroke patients for SAS is crucial due to the high risk of morbimortality and functional consequences associated to SAS following stroke but cannot be achieved without a more accurate identification of patients at risk to develop SAS following stroke. The third axis has been conceived as a perspective that will serve the development of the second axis. In this last axis, the potential of brain imagery and in particular magnetic resonance imagery to develop markers of stroke recovery as well as investigate the pathophysiological mechanisms underlying stroke-related deficiencies are presented, with a specific focus on gait and walking activity. The neural correlates of walking activity following stroke are highlighted, using a voxel-based lesion-symptom mapping approach (Baillieul et al., 2019, Hum. Mov. Sci.). Imagery markers of walking recovery following stroke using diffusion tensor imaging are also presented (Soulard et al. 2019, Neurology). This work on brain imagery markers of stroke recovery will further serve the development of investigations focused on the neural correlates of SAS following stroke
Grady, Katie O. "Effect of Oxygen-Limiting Tidal Conditions on Muscle Metabolism and Structure in the Giant Acorn Barnacle, Balanus nubilus". DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1706.
Correa, Lindsay E. "An evaluation of ecological responses to hypoxia in Hood Canal and an example of regional marine ecosystem-based management in practice". Thesis, 2009. http://nsgl.gso.uri.edu/washu/washuy09001.pdf.
Wessel, Julia Marina [Verfasser]. "Zelltypspezifische Regulation des Connective Tissue Growth Factor (CTGF) in renalen Zellen durch Hypoxie / vorgelegt von Julia Marina Wessel". 2010. http://d-nb.info/1007632569/34.
Eerkes-Medrano, Dafne I. "The role of oxygen and other environmental variables on survivorship, abundance, and community structure of invertebrate meroplankton of Oregon nearshore coastal waters". Thesis, 2011. http://hdl.handle.net/1957/26610.
Graduation date: 2012
Access restricted to the OSU Community at author's request from Jan. 6, 2012 - Jan. 6, 2013
Chu, Jackson Wing Four. "Influence of seasonally variable hypoxia on epibenthic communities in a coastal ecosystem, British Columbia, Canada". Thesis, 2016. http://hdl.handle.net/1828/7182.
Graduate
0329
0416
0433
jwfchu@gmail.com
Dhahri, Nouha. "Natural variability of pelagic and benthic conditions in the Gulf of St. Lawrence during the late Holocene". Mémoire, 2010. http://www.archipel.uqam.ca/3781/1/M11832.pdf.
Bertagnolli, Anthony D. "Microbial diversity, metabolic potential, and transcriptional activity along the inner continental shelf of the Northeast Pacific Ocean". Thesis, 2012. http://hdl.handle.net/1957/29353.
Graduation date: 2012
(10724124), Elizabeth B. Allmon. "Cardiotoxic effects of polycyclic aromatic hydrocarbons and abiotic stressors in early life stage estuarine teleosts". Thesis, 2021.