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1
Armistead, Mary Allyson. "The Middle English Physiologus: A Critical Translation and Commentary." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31894.
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The tradition of the "Physiologus" is an influential one, and informed medieval literature â not to mention medieval art and architectureâ more than we know. The "Physiologus" was â an established source of Medieval sacred iconography and didactic poetryâ and still continues to rank among the â books which have made a difference in the way we thinkâ (Curley x). Thus, our understanding of the "Physiologus" and its subsequent tradition becomes increasingly important to the fields of medieval literature, humanities, and art.
Considering the vast importance of the "Physiologus" tradition in the Middle Ages, one would expect to find that scholars have edited, translated, and studied all of the various versions of the "Physiologus". While most of the Latin bestiaries and versions of the "Physiologus" have been edited, translated, studied, and glossed, the "Middle English (ME) Physiologus"â the only surviving version of the "Physiologus" in Middle Englishâ has neither been translated nor strictly studied as a literary text. In light of the "Physiologus" traditionâ s importance, it would seem that the only version of the "Physiologus" that was translated into Middle English would be quite significant to the study of medieval literature and to the study of English literature as a whole.
Thus, in light of this discovery, the current edition attempts to spotlight this frequently overlooked text by providing an accurate translation of the "ME Physiologus," critical commentary, and historical background. Such efforts are put forth with the sincere hope that such a critical translation may win this significant version of the "Physiologus" its due critical and literary attention.Master of Arts
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Charpier, Marion. "Le dragon médiéval. "Physiologus", encyclopédies et bestiaires enluminés (VIIIe-XVe s.) : Texte et Image." Thesis, Paris, EHESS, 2020. http://www.theses.fr/2020EHES0180.
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L’omniprésence du dragon dans l’espace géographique de l’Occident médiéval en fait une figure fondamentalement complexe. Face à une production insondable, aussi immense que le dragon lui-même, les bestiaires latins offrent un corpus qui, grâce au rapport texte-image, permet d’analyser sa symbolique et son iconographie. La production des bestiaires s’inscrit dans la continuité du Physiologos grec (IIe/IVe siècle) et de ses traductions latines, et précède le renouveau encyclopédique du XIIIe siècle. Il nous importera donc de comprendre la formation et les processus qui sous-tendent l’évolution symbolique et l’iconographie du dragon, de cerner les différentes étapes qui jalonnent son histoire et ont contribué à forger son image à l’époque médiévale. Pour cela, il est nécessaire de dégager les différentes composantes symboliques du dragon biblique, à l’origine même du monstre médiéval, à travers l’Ancien Testament, l’Apocalypse et la patristique. Cette analyse a vocation de cerner les réseaux complexes et enchevêtrés qui régissent la symbolique du dragon dans le Physiologos et ses traductions latines. L’étude des traductions en langue vernaculaire des versions latines Physiologus permet de mettre en avant les permanences et mutations du dragon qui s’amorcent au cours du XIIe siècle. Les bestiaires latins permettent de comprendre les liens qui unissent et distinguent le dragon des différents serpents. Les encyclopédies du XIIIe siècle, en compilant les savoirs antiques et les traditions médiévales, redéfinissent la place du dragon dans la Création et son symbolisme. L’analyse iconographique des bestiaires permet de déterminer les critères inhérents à la physionomie du dragon, sa singularité par rapport aux autres serpents et de comprendre comment sa mise en scène participe à l’exaltation de sa nature diaboliqueThe ubiquitous of the dragon in the geographical area of the Medieval West makes it a fundamentally complex figure. Faced with an unfathomable production, as immense as the dragon itself, the Latin bestiaries offer a corpus which, thanks to the text-image relationship, allows us to analyse its symbolism and iconography. The production of the bestiaries is a continuation of the Greek Physiologos (2nd/4th century) and its Latin translations, and predates the encyclopaedic revival of the 13th century. It will therefore be important for us to understand the formation and processes underlying the symbolic evolution and iconography of the dragon, to identify the different stages that mark its history and contributed to molding its image in medieval times. To do this, it is necessary to identify the different symbolic components of the biblical dragon, at the very origin of the medieval monster, through the Old Testament, the Revelation and Patristic. This analysis aims to identify the complex and intertwined networks that govern the symbolism of the dragon in the Physiologos and its Latin translations. The study of the vernacular translations of the Latin versions of the Physiologus allows us to highlight the permanence and mutations of the dragon which began during the 12th century. The Latin bestiaries allow us to understand the links that unite and distinguish the dragon from the various snakes. The 13th century encyclopaedias, by compiling ancient knowledge and medieval traditions, redefine the place of the dragon in Creation and its symbolism. The iconographic analysis of the bestiaries allows us to determine the criteria inherent to the physiognomy of the dragon, its singularity in relation to other snakes and to understand how its depiction participates in the exaltation of its diabolical nature
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Hohlfeld, Ivo. "Wechselwirkungen zwischen Atmung und Bewegung bei Fingerfolgetests unter besonderer Berücksichtigung des Einflusses der Atmung auf Lerneffekte bei feinmotorischen Aufgaben." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-102012.
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Der Stellenwert feinmotorischen Könnens und Handelns steigt im Zeitalter der globalen Vernetzung und Technisierung kontinuierlich an. Das Erlernen solcher motorischer Abläufe unterliegt vielen Einflüssen und Störgrößen. Aus vorangegangenen Arbeiten ist bekannt, dass die Atmung nicht nur mechanische, sondern auch zentralnervöse Einflüsse auf die Geschwindigkeit und Genauigkeit anderer Muskelaktivitäten hat. In der vorliegenden Arbeit wurden an 16 Probanden mittels sprungförmiger Fingerfolgetests Lerneffekte bei feinmotorischen Bewegungen in Abhängigkeit von der Atmungsphase untersucht. Die Dauer eines Versuches lag im Mittel bei 15 Minuten mit einer Sprunghäufigkeit von ca. 8 Sprüngen pro Minute. Ziel war es, einer digital über Monitor präsentierten sprungförmigen Vorgabefunktion
durch eine Fingerbeugung so schnell und so genau wie möglich zu folgen. Die Folgegenauigkeit – dargestellt durch den Regelfehler – verbesserte sich im Laufe des Versuchs nur geringfügig (p = 0.6). Die Kennwerte der Geschwindigkeit (Latenzzeit, Anstiegszeit) wurden dagegen über die Versuchszeit schlechter. Letzterer Befund lässt sich eher als Folge von Ermüdung und nachlassender Konzentration interpretieren. Unter Berücksichtigung der Atmungsphase konnten wir
dagegen einen positiven Lerneffekt mit signifikanter Verbesserung der
Folgegenauigkeit bei den Sprüngen nachweisen, die in der frühen Exspiration ausgelöst wurden. Dieses Ergebnis zeigt, dass feinmotorisches Lernen atmungsphasenabhängig moduliert wird.
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Kaminski, Hannah. "Insights into the physiology of the gamma-delta T Physiologie des lymphocytes T gamma-delta dans l'interaction du cytomégalovirus avec son hôte immunodéprimé." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0328.
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Le cytomégalovirus est une cause infectieuse majeure de morbi-mortalité après une transplantation rénale. Une meilleure connaissance des acteurs du système immunitaire impliqués dans la réponse contre le CMV et de l'effet des médicaments immunosuppresseurs sur ces acteurs permettrait d'améliorer la prise en charge des patients. Nous avons précédemment démontré que les lymphocytes T γδ (LTγδ) (et plus particulièrement les populations n'exprimant pas la chaine Vδ2 du TCR) avaient des caractéristiques de cellules adaptatives et étaient des cellules effectrices clés répondant au CMV et associées à la guérison. Dans un premier temps, nous avons analysé le répertoire et les fonctions des lymphocytes T γδ Vδ2neg naïves pour mieux connaître leurs propriétés "innées" grâce à une analyse transcriptomique à l'échelle de la cellule (single cell RNASeq). Deuxièmement, un sous-groupe de LTγδ, les Vγ9negVδ2pos ayant également des caractéristiques adaptatives a été récemment décrit chez l'adulte. Nous avons montré que ces LTγδ Vγ9negVδ2pos sont également des composants de la réponse immunitaire contre le CMV tout en présentant des caractéristiques distinctes de celles des LTγδ Vδ2neg. Notamment, les LTγδ Vγ9negVδ2pos étaient le seul sous-groupe de LTγδ dont l'expansion était corrélée à la gravité de la maladie à CMV. Par conséquent, ce travail évalue un nouvel acteur dans la réponse immunitaire contre le CMV et ouvre des perspectives cliniques intéressantes pour l'utilisation des LTγδ Vγ9negVδ2pos comme immuno-marqueur de la gravité de la maladie à CMV.Enfin, nous avons analysé l'effet des inhibiteurs mTOR (mTORi), traitement anti-rejet utilisé en transplantation rénale, sur les lymphocytes T spécifiques du CMV. En effet, les mTORi sont associés à une moindre incidence d'infection à CMV chez les receveurs séropositifs (R+) de greffes de rein (KTR) mais leur impact sur la réponse T n'est pas connu. Nous avons émis l'hypothèse que la réactivation du CMV chez les patients R+ pourrait être due à une dysfonction des lymphocytes T qui pourrait être améliorée par les mTORi. Nous avons d'abord montré que les lymphocytes T alpha-bêta et gamma-delta présentaient un phénotype plus dysfonctionnel (LAG3+, TIM3+, PD-1+, CD85j+) à la transplantation chez les 16 R+ KTR chez qui survenait une réactivation sévère du CMV par rapport aux 17 patients sans reactivation ou avec une infection spontanément résolutive. Les patients sous mTORi (n=27) avaient une proportion diminuée de lymphocytes T alpha-beta et gamma-delta PD-1+ et CD85j+ par rapport aux patients traités par acide mycophénolique (MPA) (n=44), ce qui était corrélé avec une fréquence et une gravité moindre des infections à CMV. Les patients sous mTORi présentaient également des proportions plus élevées de lymphocytes T cytotoxiques. In vitro, les mTORi augmentaient la prolifération, la survie et la production d'interferon-gamma contre le CMV par les lymphocytes T alpha-beta et gamma-delta. Les proportions de cellules PD-1+ et CD85j+ étaient également diminuées sous mTORi dans les deux sous-populations et leur profil majoritaire devenait "EOMES low/ Hobit high". Dans les lymphocytes T gamma-delta, l'effet des mTORi était lié à une augmentation de la signalisation TCR. Ces résultats révèlent (i) qu'une réplication sévère du CMV est associée à un profil dysfonctionnel des lymphocytes T et (ii) que les mTORi améliorent leur aptitude de façon associée au meilleur contrôle du CMV. Le phénotype de lymphocytes T dysfonctionnel pourrait représenter un nouvel immuno-marqueur chez les patients R+ pour prédire l'infection post-transplantation et aider à stratifier les patients qui devraient bénéficier du traitement mTORiCytomegalovirus is a major infectious cause of mortality and morbidity following transplantation and a better knowledge about the immune cells acting against CMV and about their response to immunosuppressive drugs would help to better manage this life threatening infection. We have previously demonstrated that the tissue-associated adaptive Vδ2neg γδ T-cells are key effectors responding to CMV and associated to recovery. We analyzed here the repertoire and functions of naive Vδ2neg γδ T-cells to know better their "innate" properties against CMV. Secondly, an additional Vγ9negVδ2pos subgroup with adaptive functions has been recently described in adults. We demonstrated that these Vγ9negVδ2pos T-cells are also components of the CMV immune response while presenting with distinct characteristics from Vδ2neg γδT-cells. Notably Vγ9negVδ2pos T-cells were the only γδ T-cell subset which expansion tightly correlated with the severity of CMV disease. Consequently, we identified a new player in the immune response against CMV and open interesting clinical perspectives for using Vγ9negVδ2pos T-cells as an immune marker for CMV disease severity in immunocompromised patients.Finally, we analyzed the effect of mTOR-inhibitors (mTORi), immunosuppressive drugs, on CMV-specific T cells. Indeed, mTORi are inexplicably associated with a lower incidence of CMV infection in seropositive (R+) kidney transplant recipients (KTR). We hypothesized that CMV reactivation in R+ patients could be due to dysfunctional T cells that might be improved by mTORi. First we showed that both alpha-beta and gamma-delta T cells displayed a more dysfunctional phenotype (LAG3+, TIM3+, PD-1+, CD85j+) at day 0 in the 16 R+ KTR with severe CMV reactivation when compared to the 17 with spontaneously resolving or without CMV reactivation. Second, treating patients with mTORi (n= 27) decreased the proportion of PD-1+ and CD85j+ alpha-beta and gamma-delta T cells when compared to mycophenolic acid (MPA) treated patients (n=44), which correlate with the frequency and severity of CMV infections. mTORi-treated patients also lead to higher proportions of late-differentiated and cytotoxic gamma-delta T cells and increased percentages of IFN-gamma producing and cytotoxic alpha-beta T cells. In vitro, mTORi increased proliferation, survival and CMV-induced IFN-gamma-production of alpha-beta and gamma-delta T cells. mTORi also decreased PD-1 and CD85j expression in both subsets and shifted to a more efficient EOMESlow Hobit high profile. In gamma-delta T cells mTORi effect was related to increased TCR signaling. Those results reveal (i) that severe CMV replication is associated with a dysfunctional T cell profile and (ii) that mTORi improve their fitness in association with a better control of CMV. Dysfunctional T cell phenotype could represent a new biomarker in R+ patients to predict post-transplantation infection and help to stratify patients who should benefit from mTORi treatment
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Matelot, David. "Limites des adaptations cardiovasculaires des sportifs endurants." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1B028/document.
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Cette thèse visait à explorer trois limites des adaptations cardiovasculaires des sportifs endurants. Les athlètes endurants bradycardes ont-ils un risque augmenté de présenter des syncopes réflexes et des particularités électrocardiographiques par rapport à leurs homologues non bradycardes ? Commencer un entraînement après 40 ans est-il trop tard pour espérer améliorer sa santé cardiovasculaire ? La fatigue cardiaque retrouvée à l’issue d’efforts longs et intenses chez les coureurs à pied est-elle également induite par des efforts pratiqués essentiellement avec les bras comme le canoë-kayak ou par les efforts pratiqués par les militaires durant leurs stages intensifs ? Tout d’abord, l’étude BRADY suggère que chez des athlètes endurants de même niveau qui diffèrent uniquement par leur FC de repos (44 vs 61 batt.min-1) les bradycardes ne sont pas plus à risque de syncopes réflexes ni de particularités électrocardiographiques que les non bradycardes. L’hypertrophie cardiaque, plus importante chez les bradycardes, pourrait jouer un rôle central dans le développement de la bradycardie du sportif. Deuxièmement, l’étude COSS suggère que commencer un entraînement en endurance après 40 ans n’est pas trop tard pour être en meilleure santé cardiovasculaire à 60 ans. En effet le VO2max, la FC de repos ainsi que la balance sympathovagal ne diffèrent pas chez des seniors de 60 ans ayant commencé à s’entraîner avant 30 ans de chez ceux ayant commencé après 40 ans. Ces indices de la santé cardiovasculaire étaient meilleurs dans ces deux groupes par rapport aux personnes n’ayant jamais suivi un entraînement en endurance. Seul un entraînement initié avant 30 ans semble cependant apporter certains bénéfices vasculaires à l’effort, non retrouvés chez les seniors ayant commencé après 40 ans. Enfin, l’étude FACEFI visait à évaluer les conséquences cardiaques de 3 types d’efforts : 3 semaines d’entraînements intenses en canoë-kayak au pôle France de Cesson-Sévigné, 24h d’un stage d’aguerrissement chez des élèves des Écoles de Saint-Cyr Coëtquidan, et 4 jours d’un stage chez les Commandos de Marine. Seule une partie des résultats obtenus chez les Commandos de Marine a été analysée. Ils indiquent que 3 jours et 3 nuits d’un stage commando, finalisés par une marche forcée de 20 km en portant une charge de 20 kg, ne semblent pas altérer ni les dimensions ni les fonctions cardiaques. La durée relativement faible de l’effort (< 2h45), le très bon niveau d’entraînement des sujets, ainsi que la composante en résistance importante des efforts réalisés, peuvent expliquer ce résultatThis PhD Thesis aimed to answer three limits related to cardiovascular adaptations in endurance athletes. Are bradycardic endurance athletes more at risk of reflex syncope and of ECG abnormalities than their non-bradycardic counterparts? Is 40 years old too late to start endurance training in order to improve cardiovascular health in later life? Cardiac fatigue has been shown after long-term intense running events, but do canoeing or military training induce the same alteration? First, BRADY study showed that endurance-trained bradycardic athletes are not more prone to reflex syncope or ECG abnormalities than their non-bradycardic peers. Our results suggest that cardiac hypertrophy may be, at least in part, responsible for the developement of training-induced bradycardia. Second, COSS study showed that commencing structured endurance training after 40 years of age is powerful enough to induce beneficial alterations in VO2max, resting HR, and autonomic status that match those observed in individuals who commenced training prior to 30 years of age. However, only endurance training commenced before 30 years old provides enhancement of certain vascular adaptations during exercise. Last, preliminary results of FACEFI study showed that a 4-day military selection camp does not lead to cardiac fatigue. The relative short duration of the last exercise (< 2h45), the high level of training of the subjects, and the important strenght- related part of the exercices may explain the lack of cardiac fatigue. Data from 4 weeks of canoeing training and 24h of military training in other groups of athletes are in process
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Jrad, Lamine Aïcha. "Impact de l'invalidation du gène codant pour l'indoleamine 2,3-dioxygénase dans la physiologie de l'épididyme chez les mammifères." Thesis, Clermont-Ferrand 2, 2012. http://www.theses.fr/2012CLF22263/document.
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Chez les mammifères, IDO1, une enzyme induite dans les situations inflammatoires, joue des rôles multiples et complexes dans le cadre des réponses immunes innées et acquises. De façon intéressante, IDO1 est constitutivement exprimée par l’épithélium épididymaire où il est envisagé qu’elle participe à l’installation d’une situation d’immunotoloréance vis à vis des spermatozoïdes lesquels constituent un « challenge »immunologique pour le mâle qui les fabrique. Afin d’aborder le(les) rôle(s) joué(s) parIDO1 et ses produits d’activité (ie. les kynurénines) dans la physiologie de l’épididyme et, plus largement, dans la fonction de reproduction, le travail présenté dans ce manuscrit décrit les résultats acquis sur le modèle murin Ido1-/-en termes de phénotypes épididymaires, spermatiques ainsi qu’en terme d’impact sur la fertilité des animaux KO. Les données présentées suggèrent qu’IDO1 est effectivement un acteur immunosuppresseur dans l’épithélium épididymaire contribuant au privilège immunaccordé par ce territoire aux gamètes mâles. L’absence d’IDO1 génère au sein de l’épididyme des perturbations d’ordre inflammatoire néanmoins corrigées par diverses réponses qui préservent l’équilibre immun et fonctionnel du tissu. Ce travail met en outre en évidence que certaines kynurénines sont particulièrement représentées dans l’épididyme et au niveau des gamètes mâles où elles pourraient jouer des rôles variésIn mammals, IDO1 is induced in inflammatory situations and plays multiple and complicated roles in the modulation of both innate and adaptative immune responses. Interestingly, IDO1 is constitutively expressed by the epididymal epithelium where it is envisaged that it participates in the set up of an immunotolerant environment in order to down-regulate auto immune-responses against spermatozoa. To decipher the roles played by IDO1 in the physiology of the epididymis and consequently in the male reproductive function, we show in this thesis report data obtained on the IDO1 knock-out mouse model. Data collected suggest that indeed IDO1 is an immunomodulatory player in the epididymis epithelium where it contributes to the immunotolerogenic context towards spermatozoa. When absent (ie. in the Ido1-/- genetic background) it specifically increases epididymal inflammation and triggers various tissue responses that aim at restoring the immune equlibrium. In addition, the work presented here shows that some kynurenines are particularly well represented in the epididymal epithelium as well as on spermatozoa where they could play important roles
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Cattelain, Thibault. "Production des consonnes plosives du français : du contrôle des bruits de plosion." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAS011/document.
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L’étude de la production des consonnes occlusives (/p/, /b/, etc) a un intérêtparticulier pour la compréhension du contrôle moteur de la production de la parole. Eneffet, la production de ces consonnes requiert une coordination fine des 3 niveaux deproduction : respiration, vibration des cordes vocales, articulation.L’objectif de mes travaux de thèse est d’étudier la coordination des gestesrespiratoires, laryngés et articulatoires permettant de contrôler la variation de certains traits acoustiques des consonnes occlusives, plus spécifiquement les caractéristiques acoustiques de leurs bruits de plosion (intensité, durée, spectre, cruciaux pour l’intelligibilité des consonnes occlusives). Une partie importante de mes travaux de thèse s’intéresse également au contrôle musculaire de cette coordination gestuelle.Ces objectifs demandent un travail méthodologique préliminaire pour comparer,développer et implémenter différentes techniques de mesure et d’estimation des effortsarticulatoires de production de parole, à différents points de vue, physiologiques etmécaniques (cinématique du mouvement labial, capteurs de force, électromyographieorofaciale). L’exploration de ces questions a donné lieu à l’acquisition d’une large base de données (acoustiques et physiologiques) de production de consonnes occlusives du français chez une vingtaine de locuteurs adultes sains, incluant 2 modes de phonation (modal et chuchoté), 2 débits de parole (normal et rapide) et plusieurs niveaux d’effort articulatoire.L’analyse de cette base de données a permis de confirmer certaines relations déjà établies en parole conversationnelle entre l’intensité acoustique du bruit de plosion et le maximum de Pression Intra-Orale (ou la vitesse d’ouverture des lèvres pour les consonnes labiales), et entre les paramètres spectraux du bruit de plosion (skewness et kurtosis) et les paramètres articulatoires de déplacement de la langue pour les consonnes alvéolaires et vélaires.D’autres relations (non décrites dans la littérature) ont été observées en paroleconversationnelle : 1- l’intensité acoustique du bruit de plosion augmente lorsque le degré de compression labial et la vitesse de fermeture des lèvres augmentent pour les consonnes labiales ; 2- l’intensité acoustique du bruit de plosion augmente lorsque la vitesse tangentielle du mouvement d’élévation de la langue augmente pour les consonnespalatales ; 3- le degré de compression labial, les vitesses de fermeture et d’ouverture des lèvres augmentent significativement lorsque les activités des muscles Orbicularis Oris Supérieur (OOS) et Dépresseur de la Lèvre Inférieure (DLI) augmentent (dans les phases du mouvement où ils sont agonistes). Ces relations évoluent en fonction du mode de phonation (l’accent est mis en qualité chuchotée sur l’utilisation de paramètres cinématiques au détriment des paramètres aérodynamiques, articulatoires et temporels) et du débit de parole (la plupart des paramètres physiologiques et articulatoires perdent avec le débit leur efficacité de contrôle des caractéristiques acoustiques)Stop consonants (/p/, /b/, etc) are of particular interest for the understanding of speech motor control. Indeed, the production of these stop consonant requires the coordination of the 3 production levels: breathing, vocal folds vibration and articulation.The main goal of my thesis is to study how respiratory, laryngeal and articulatory gestures coordinate to control the variation of acoustic features of stop consonants, especially of their burts (intensity, duration, spectrum), which are crucial for stop consonant intelligibility. An important part of my thesis work also focuses on the muscular control of lip gestures in the production of bilabial stops. These goals needed a preliminary methodological work to compare, develop and implement different techniques, in order to measure and estimate articulatory efforts of speech production, physiologically and mechanically (lip movement kinematics, force sensors, orofacial electromyography). This methodological exploration has given rise to theacquisition of a large database (acoustic and physiological data) of French stop consonant productions, for twenty healthy speakers, including 2 phonation modes (modal and whispered), 2 speech rates (normal and fast) and several levels of articulatory effort.The analysis of this database has confirmed relationships already established inconversational speech between burst intensity and the maximum of intra-oral pressure (or opening velocity of lips for labial stops), and between spectral features of the burst and articulatory parameters of tongue movements for alveolar and velar stops. New other relationships have been observed in conversational : 1- the burst acoustic intensity increase when the lips compression and opening velocity increase (for labial stop consonants) ; 2-the burst acoustic intensity increase when the elevation tangential velocity of the tongue increase (for palatal stop consonants) ; 3- the lips compression, lips opening and closing velocities significantly increase when the activities of the OOS (Superior Orbicularis Oris) and DLI (Depressor of the Inferior Lip) muscles increase (during the movement phasis where muscles are agonists). These relationships depend on phonation quality (in whispered speech the accent is made on using kinematic parameters at the cost of aerodynamic, articulatory and temporal ones) and speech rate (most of physiological and articulatory parameters lost efficacies for acoustic control when speech rate increase)
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Whitlock, T. L. "Muscle physiology instrumentation." Thesis, University of Bath, 1990. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236467.
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Marchand-Alain, Sabine. "Physiologie de la ménopause." Paris 5, 1988. http://www.theses.fr/1988PA05P268.
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Constantinidès, Yannis. "Nietzsche et la physiologie." Paris 1, 2005. http://www.theses.fr/2005PA010687.
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Ce travail s'efforce de préciser le statut de la physiologie dans la pensée de Nietzsche, qui prend de manière générale "le corps comme fil conducteur ". Notre point de départ est l'idée que le corps lui-même " connaît" et " pense ", la pensée consciente n'étant qu'un épiphénomène de cette forme primitive d'appréhension du monde. Cela oblige à réévaluer la physiologie philosophique de Nietzsche, rarement étudiée pour elle-même. Adopter ce point de vue fondamental, génétiquement premier, permet en outre de mieux comprendre l'éthique naturaliste de Nietzsche et de proposer une nouvelle interprétation de la "grande politique ", à partir notamment d'un rapprochement avec le projet platonicien d'élevage d'une aristocratie du corps et de l'esprit. Nous examinons tout particulièrement l'approche physiologique dans son rapport à la question de l'héritage axiologique, puisque les jugements de valeur sont hérités pour Nietzsche.
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Bendavid, Marie. "L'acné : physiologie et traitement." Paris 5, 1989. http://www.theses.fr/1989PA05P023.
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Forêt, Martin. "Les migrations secondaires des recrues de bivalves : approche éco-étho-physiologique." Thesis, Paris, Muséum national d'histoire naturelle, 2018. http://www.theses.fr/2018MNHN0017/document.
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Le recrutement est un processus clé du cycle de vie des invertébrés marins benthiques, dont les bivalves. Si la phase larvaire et l’étape de fixation/métamorphose sont largement étudiées, les processus post-fixation, dont font partie les migrations secondaires, restent relativement ignorés ou du moins sous-estimés.Ces migrations secondaires ou post-fixations résultent de processus hydrodynamiques modulés par des réponses éco-éthologiques.Le présent projet proposait d’étudier les mécanismes de migrations secondaires des recrues de bivalves en développant une approche éco-étho-physiologique afin de répondre à trois objectifs : i) Estimer le poids potentiel des migrations secondaires dans les habitats de sédiments grossiers ii) Identifier des facteurs environnementaux, et plus spécifiquement ceux de l’environnement trophique en relation avec l’hydrodynamisme, qui contrôlent ces processus iii) Évaluer les potentielles interactions entre migrations secondaires et physiologie des recrues. Dans un premier temps, nous avons développé une étude in-situ des migrations secondaires des recrues de bivalves dans un habitat de sédiments grossiers dans l’archipel de Chausey (Normandie, France) via l’utilisation de pièges à recrues. En parallèle, un suivi de nombreux paramètres environnementaux (conditions hydrologiques, hydrodynamiques et trophiques) a été mis en place. Puis, nous avons étudié en conditions expérimentales, le potentiel de dispersion post-fixation de différentes espèces de bivalves exploitées et l’influence de la physiologie (en termes de réserves énergétiques) sur les migrations secondaires. Pour ce faire, nous avons utilisé des outils innovants, tels un tube de vitesse de chute et un canal hydrodynamique tout en développant la zootechnie de l’élevage larvaire et poste-larvaire de la praire, Venus verrusosa. Nos résultats mettent en évidence l’importance des migrations secondaires des recrues de bivalves dans les habitats de sédiments grossiers avec près de 24 taxons différents de bivalves identifiés en migration. Certaines de ces migrations post-fixations correspondraient à des changements ontogéniques d’habitats, et les habitats de sédiments grossiers constitueraient une zone de nurserie pour plusieurs espèces. De plus, ce projet démontre, pour la première fois, le rôle de la physiologie et de l’environnement trophique dans le contrôle des migrations secondaires et cela à différents niveaux. Nous avons observé une synchronisation entre un événement massif de migrations secondaires actives et un changement de la composition de la communauté phytoplanctonique, plus particulièrement un bloom de nanoeucaryotes. Cette réponse des recrues de bivalves à un signal trophique pélagique («trophic migration trigger», TMT), pourrait être due au coût énergétique supplémentaire associé aux comportements actifs de migration. En effet, nous avons ensuite constaté en conditions expérimentales que la capacité des recrues à contrôler leur dispersion par leur comportement est directement corrélée avec leur profil physiologique. Les recrues avec le plus de réserves énergétiques ont une meilleure capacité d’accroître leur potentiel de dispersion par leur comportement. Aussi les recrues migreraient quand leur principale source de nourriture est disponible dans le milieu afin de mieux supporter le coût des comportements de migrations secondaires actives comme la dérive byssopélagique. De plus, le potentiel de migration post-fixation apparait comme fortement lié à la synchronicité entre la période d’arrivée de la larve sur le sédiment et le cycle de marée (morte-eau ou vive-eau), mais également aux taux de croissance post-larvaires qui dépendent eux-mêmes de l’environnement trophique. Les patrons de migrations secondaires des recrues bivalves résultent donc d'un étroit couplage physico-biologique impliquant l'hydrodynamique, mais aussi des réponses éco-éthologiques modulées par des processus physiologiques en lien avec l’environnement trophiqueRecruitment is a key process in the life-cycle of benthic marine invertebrates, and most of bivalve species. It includes the larval phase, the settlement and secondary dispersal mechanisms which lead to a gradual sedentary lifestyle until the recruits begin a strict benthic life. Although the larval phase and the settlement/metamorphosis stage are well studied, post-settlement migrations remain relatively unknown or at least underestimated. These migrations are the result of hydrodynamic processes modulated by eco-ethological responses in the benthic boundary layer that can radically change primary fixation patterns and have a major impact on the life cycle of a bivalve.This project proposed to study secondary migrations mechanisms of bivalve recruits by developing an eco-etho-physiological approach in order to answer three objectives: I) estimate the potential weight of the secondary migrations in coarse sediments habitats, ii) identify environmental factors, and more specifically those of the trophic environment in relation to hydrodynamics conditions, which control these processes, iii) evaluate the potential interactions between secondary migrations and recruits physiology.Firstly, we developed an in-situ study of secondary migrations of bivalve recruits in a coarse sediment habitat in the Chausey Archipelago (Normandy, France) by using recruit traps and monitoring environmental parameters (hydrological, hydrodynamic and trophic conditions). Then, we studied in experimental conditions post-settlement dispersal potential of different exploited bivalve species as well as the influence of physiology (in terms of energy reserves) on secondary migrations with a fall velocity tube, a benthic flume and by developing the larval and post-larval rearing of the warty venus, Venus verrucosa. Our results highlight the importance of secondary migrations of bivalve recruits in coarse sediment habitats with nearly 24 different taxa of bivalves identified in migration. Some of these post-settlement migrations would correspond to ontogenic change of habitat, and so coarse sediment habitats would constitute a nursery zone for several species. For the first time, this project demonstrates, at different levels, the role of physiology and trophic environment in the control of secondary migrations. We observed synchronization between a massive active secondary migration event with a change in the composition of the phytoplankton community and more particularly a bloom of nanoeukaryotes. This response of bivalve recruits to a ‘’trophic migration trigger’’ (TMT) could be due to the additional energy cost of active migration behaviors. Indeed, we highlighted, in experimental conditions, that the ability of recruits to control their dispersal by their behavior is directly correlated with their physiological profile. Recruits with the most energy reserves are the most able to increase their dispersal potential by their behavior. Also recruits would migrate when their main food source is available in the environment in order to support the cost of active secondary migration behaviors such as bysso-pelagic drift. In addition, post-fixation migration potential appears to be strongly related to the synchronicity between the settlement period and the tidal cycle (spring tide or neap tide), but also to post-settlement growth rates which depend on trophic conditions. Patterns of secondary migrations result from a close physico-biological coupling involving hydrodynamics factors but also eco-ethological responses modulated by physiological processes related to the trophic environment
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Shirangi, Seyedeh Ainaz. "Mécanismes osmorégulateurs chez les juvéniles d'esturgeon perse (Acipenser persicus) durant une acclimatation à la salinité de la mer Caspienne." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT174/document.
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Afin de repeupler la mer Caspienne, la propagation artificielle de l’esturgeon Acipenser persicus est maintenant une pratique courante avec rejets annuels de juvéniles directement en mer. Cependant, une forte mortalité est régulièrement observée suite à la libération directe en mer de juvéniles pesant 2-3 g. L'objectif a donc été d'analyser les capacités d’acclimatation de juvéniles de l’eau douce à l’eau saumâtre et d'identifier un moyen possible d’améliorer les taux de survie d’esturgeons de moins de 3 g.Dans une première partie, l'effet de transferts abruptes ou progressifs sur 5 jours de l'eau douce (ED) à une salinité de 11‰ (salinité de la mer Caspienne, CSW) a été étudié chez des juvéniles de 1 à 2 g, 2 à 3 g et de 3 à 5 g. Ont été mesurés les taux de mortalité, l'osmolalité plasmatique, l’expression et la localisation (branchies, reins, valvule spiralée, caecum pylorique) des principales protéines de transport : la Na+, K+-ATPase (NKA), la H+-ATPase vacuolaire (VHA), le Na+, K+, 2Cl- (NKCC) et la ‘Cystic Fibrosis Transmembrane conductance Regulator’ (CFTR). Une étude des changements d'expression génique et protéique de la NKA au niveau des branchies a également été effectuée. Enfin, une étude ultrastructurale (TEM et SEM) des cellules à chlorure branchiales a été effectuée.Dans une deuxième partie, un traitement hormonal avec le cortisol a été effectué afin d’améliorer la capacité d'acclimatation. Des juvéniles de moins de 2g ont été traités pendant 24h en ED avec des bains de cortisol à 3 concentrations différentes : 3, 5 et 7 mg.l-1. Les poissons ont été ensuite directement transférés de l'eau douce à la CSW et échantillonnés après 1, 4 et 9 jours après transfert en CSW. Les taux de mortalité, l'osmolalité plasmatique, le nombre et l’aire des cellules à chlorure des branchies ont été évalués.Ainsi, les poissons de plus de 3 g sont capables de survivre et s’acclimatent à la CSW. Malgré une augmentation initiale de l'osmolalité plasmatique après transfert de salinité, les juvéniles réduisent ensuite leur osmolalité plasmatique jusqu'à la pression osmotique de la mer Caspienne. Cependant, beaucoup de poissons de moins de 3 g ne peuvent survivre à l’augmentation brutale de salinité et la pression osmotique du sang des poissons survivants reste élevée. L’expression de la NKA et du NKCC, la taille et le nombre des cellules à chlorure des branchies sont également plus élevés. Les juvéniles pesants plus de 2 g augmentent aussi fortement leur activité de NKA branchiale après transfert de salinité. L'étude ultrastucturale a révélé des surfaces apicales similaires pour les cellules à chlorure branchiales des poissons en ED et acclimatés à la CSW. Le cytoplasme de ces cellules dans les poissons pesant plus de 2 g apparait plus dense et gonflé par rapport aux poissons pesant moins de 2 g. Cela pourrait être dû à l'allongement des replis de la membrane basale (réseau tubulo-vésiculaire) et/ou à une densité plus élevée des mitochondries. L’expression branchiale du gène NKA des poissons acclimatés à la CSW est apparue d'abord sur- puis sous-exprimée 4 jours après le transfert de salinité pour atteindre le niveau des poissons en ED. Au niveau intestinal et des reins, aucune différence n'a pu être détectée entre les différents groupes de poids suite au transfert de salinité. Malgré une osmolarité plasmatique réduite, le nombre et la taille des cellules à chlorure des poissons traités avec le cortisol montrent 9 jours après transfert, les mêmes tendances que celles observées pour les poissons non traités.Ainsi, cette étude a révélé que seuls les esturgeons juvéniles de plus de 3 g peuvent être directement rejetés en mer Caspienne. Pour les poissons de 2-3 g, un protocole spécial pendant le transfert de salinité doit être considéré alors que les poissons pesant moins de 2 g ne peuvent tolérer une augmentation de salinité même après un traitement au cortisolFor restocking purposes, artificial propagation of Persian sturgeon (Acipenser persicus) and annual releases into the Caspian Sea are now common practice. However, high mortality is regularly observed following the direct release of 2-3 g juveniles into the Caspian Sea. Therefore, the aim of the study was to analyse the acclamatory capacities of juvenile Persian sturgeons to elevated salinity and to identify a possible way to improve survival rates of juveniles weighting less than 3 grams.In the first part of this study, the effect of abrupt and 5-day gradual salinity transfers from freshwater (FW) to 11‰ Caspian Sea water (CSW) were investigated in juvenile Persian sturgeons with three different weight groups: 1-2 g (1.62 ± 0.27 g), 2-3 g (2.55 ± 0.41 g) and 3-5 g (4.28 ± 0.76 g). Daily mortality rates, plasma osmolality, immunofluorescence localization of the main ion transporter proteins such as Na+, K+-ATPase (NKA), Vacuolar H+-ATPase (VHA), Na+,K+,2Cl–(NKCC) and Cystic Fibrosis Transmembrane conductance Regulator (CFTR) at the gill, kidney, pyloric caecum and intestinal spiral valve levels, ultrastructural studies (TEM and SEM) of the gills for chloride cell changes and changes of branchial NKA gene and protein expression were measured 4 and 10 days after abrupt transfer to CSW and 9 and 15 days after the initial gradual transfer (i.e. 4 and 10 days after reaching CSW), respectively.In the second part of study, hormonal treatment with cortisol was used to enhance the acclimation capability of fish weighing less than 2g. Fish were treated with a cortisol bathing method using three different concentrations; 3, 5 and 7 mg.l-1 for 24 hours in FW. Fish were then directly transferred from FW to CSW (11‰) and sampled after 1, 4 and 9 days post-transfer to CSW. Daily mortality rate, plasma osmolality and branchial chloride cell number and area were evaluated.The obtained results showed that fish weighing more than 3g are able to survive and could successfully acclimate to CSW. Despite initial plasma osmolality increase after salinity transfer, juveniles could reduce their plasma osmolality down to the CSW osmotic pressure after 15 days of acclimation in CSW. However, fish under 3 g could not survive abrupt salinity increase, and blood osmotic pressure of the remaining surviving fish increased and remained elevated during the whole experimental period. At the gill level, higher chloride cell size and number, with also higher NKA and NKCC content were observed allowing juveniles weighing more than 2 g to sharply increase their NKA activity after salinity transfer. The electron microscopic study revealed similar apical surfaces for branchial chloride cells in FW and CSW-acclimated fish. It also indicated that the cytoplasm of these cells in fish weighing more than 2 g were denser and inflated compared to fish weighing less than 2 g. This could be due to the elongation of the basal membrane infoldings (tubulo-vesicular network) and/or a higher density of mitochondria. Because sequences of NKA and NKCC1 genes were not reported for sturgeon fish, two partial sequences of NKA (632 bp) and NKCC1 (538 bp) were obtained from this present study and were registered in Genbank. Branchial NKA gene of CSW-acclimated fish was firstly upregulated and then downregulated to the level for FW fish after 4 days following salinity transfer. At the kidney and intestinal level, no difference could be detected between the different weight groups during salinity transfer. Despite lower plasma osmolality, number and size of the chloride cells in treated fish with cortisol show the same trends as the untreated control fish after 9-days post transfer. Consequently, this study revealed that only Persian sturgeon juveniles weighing more than 3 g can directly be released into the Caspian Sea. Fish weighting 2-3 g need special care during salinity transfer and fish weighing less than 2 g cannot tolerate Caspian Sea salinity even after cortisol treatment
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Ashcroft, Felicity Jayne. "The physiology of Reg." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288281.
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Ashcroft, Neville R. "Teleost iridescent corneal physiology." Thesis, University of Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333922.
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Ayala, Felix, and Jeffrey C. Silvertooth. "Physiology of Cotton Defoliation." College of Agriculture, University of Arizona (Tucson, AZ), 2015. http://hdl.handle.net/10150/558537.
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Revised 06/2015. Originally published 07/2001.3 pp.
This bulletin deals with the physiology of cotton defoliation and attempts to describe what conditions must exist inside the plant in order for defoliation to occur. It is important to understand the basic physiological processes involved in order for best crop management practices to accomplish a successful defoliation. The objectives of defoliating a cotton crop can be simply stated as: 1) to remove leaves to facilitate mechanical picking, 2) to maintain the quality of the lint, and 3) to complete defoliation with a single application of chemicals.
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Matecki, Stefan. "Muscles respiratoires et myopathie de Duchenne : de la physiologie appliquée à la physiologie cellulaire." Montpellier 1, 2002. http://www.theses.fr/2002MON1T005.
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La baisse severe et progressive de la force des muscles respiratoires des enfants porteurs d'une myopathie (dmd) represente le probleme majeur de ces patients. [. . . ] notre premier objectif a ete de developper des mesures standardisees de la fonction des muscles respiratoires. Grace a ceux-ci nous avons pu mettre en evidence qu'un programme de reentrainement de ces muscles permettait une amelioration de leur endurance. Nous avons ensuite essaye de comprendre les mecanismes de cette amelioration en etudiant l'influence de l'exercice sur la fibre musculaire dystrophique. [. . . ] afin de mieux comprendre les eventuelles interactions entre la malnutrition decrite chez les enfants atteints de myopathie et l'effet d'un reentrainement sur l'endurance des muscles respiratoires, nous avons voulu preciser l'effet d'une denutrition prolongee sur la respiration mitochondriale du diaphragme de rat. Nous avons observe que 5 semaines de denutrition alterent l'ensemble de la respiration mitochondriale. Ce travail met donc l'accent sur l'effet benefique du reentrainement des muscles respiratoires qui semble passer par un mecanisme regulateur des proteines associees a la dystrophine et sur l'importance de la denutrition qui peut alterer cet effet.
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Salvi, Julie. "Mécanismes psysiopathologiques des ataxies épisodiques et progressives associées aux canaux calciques de type P/Q." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20229.
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Dans de nombreuses maladies héréditaires monogéniques, les bases moléculaires du mode de transmission (dominant vs récessif) et l'origine de nombreux phénotypes associés restent obscurs. C'est le cas pour les ataxies épisodiques (EA) et progressives liées au canal calcique Cav2.1. La plupart des mutations présentes dans ces ataxies génèrent une protéine mal repliée retenue et dégradée dans le réticulum endoplasmique. J'ai exploré plusieurs approches afin d'associer les phénotypes dues à la présence des mutants et ceux dues à une « pure » perte de fonction. A l'aide de vecteurs viraux codants pour des ARNs interférents de Cav2.1, j'ai montré que la réduction chez la souris adulte du canal récapitulait de nombreux symptômes de l'EA2.J'étudie également un nouveau modèle murin knock-In pour l'EA2 produisant une forme tronquée mal repliée. L'étude de ces modèles permettra une meilleure compréhension des mécanismes physiopathologiques et l'exploration de nouvelles voies thérapeutiquesVoltage-gated calcium channels (VGCC) regulate an array of physiological process. The P/Q-type VGCC is principally expressed in the cerebellum and at the neuromuscular junction, where it plays an essential role at the presynaptic neuronal nerve. Interestingly, mutations in a1 subunit (Cav2.1) of P/Q-type VGCC gene have been found to be linked for three autosomal dominant human disorders, familial hemiplegic migraine type 1 (FHM1), spinocerebellar ataxia 6 (SCA6) and episodic ataxia type 2 (EA2). Mutations causing EA2 lead to loss-of-function of Cav2.1 channels and are principally non-sense. The origin of dominant transmission and the heterogeneity of the symptoms are not known. Recent data from different groups have shown a dominant-negative effect of Cav2.1 mutants in cultured cell lines. Indeed, the molecular mechanism of this dominant-negative effect appears to be due to the interference of EA2 mutants with the folding of the wildtype subunit, thereby abolishing channel activity. This destructive interaction mechanism promoted by the EA2 mutants is likely to occur in the disease.The first part of my thesis was to monitor the effect of a “pure” silincing of P/Q-type channel in adult mice. Suppression of Cav2.1 channel by RNAi lentiviral based-vector approaches has produced episodic as well as permanent ataxia without signs of progressive ataxia. As a direct approach to understanding the physiologicalcontributions of misfolded truncated mutants in EA2 phenotypes, a Cav2.1 knock-inmutant, CACNA1AR1479x has been generated. This is a fundamental issue to understand the pathogenic mechanisms of EA2 and more generally to the other neuronal and neuromuscular diseases
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Flori, Serena. "Light utilization in microalgae : the marine diatom Phaeodactylum tricornutum and the green algae Chlamydomonas reinhardtii." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAV080/document.
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Les microalgues ont développé des approches distinctes pour moduler l'absorption de la lumière et son utilisation par leurs photosystèmes en réponse à des stimuli environnementaux. Dans ce rapport de Thèse je présente les différentes stratégies employées par une algue d'eau douce (Chlamydomonas reinhardtii) et une algue marine (Phaeodactylum tricornutum) pour optimiser leur acclimatation à l'environnement.Dans la première partie de ce rapport, je propose un modèle de cellules entières de la diatomée marine Phaeodactylum tricornutum obtenue par analyses spectroscopiques et biochimiques ainsi que par l’obtention d’images par microscopie électronique et reconstitution 3-D. Ce modèle a été utilisé pour répondre aux questions suivantes i. comment est structuré un chloroplaste secondaire pour faciliter les échanges avec le cytosol à travers les quatre membranes qui le délimitent ii. comment sont structurées les membranes photosynthétiques afin d’optimiser l'absorption de lumière et le flux d'électrons et iii. comment les chloroplastes et les mitochondries sont organisés pour optimiser l'assimilation du CO2 par échange ATP / NADPH.La deuxième partie de ce rapport porte sur la régulation de la collection de la lumière et de sa dissipation chez Chlamydomonas grâce à l'étude d'une part du rôle de la perception de la couleur de la lumière et d'autre part du métabolisme sur la dissipation de l'excès de lumière par quenching non photochimique (NPQ). En utilisant des approches biochimiques et spectroscopiques, j'ai mis en évidence un lien moléculaire entre la photoréception, la photosynthèse et la photoprotection chez Chlamydomonas via le rôle du photorécepteur phototropine, démontrant ainsi que le métabolisme, en plus de la lumière, peut aussi affecter ce processus d'acclimatation.En conclusion, ce travail de thèse révèle l'existence et l'intégration des différentes voies de signalisation dans la régulation des réponses photoprotectrices mises en place chez les microalgues marines et d'eau douceMicroalgae have developed distinct approaches to modulate light absorption and utilization by their photosystems in response to environmental stimuli. In this Ph.D Thesis, I characterised different strategies employed by freshwater (Chlamydomonas reinhardtii) and marine algae (Phaeodactylum tricornutum) to optimise their acclimation to the environment.In the first part of this work, I used spectroscopic, biochemical, electron microscopy analysis and 3-dimentional reconstitution to generate a model of the entire cell of the marine diatom Phaeodactylum tricornutum. This model has been used to address the following questions: i. how is a secondary chloroplast structured to facilitate exchanges with the cytosol via its four membranes envelope barrier ii. how have diatoms shaped their photosynthetic membranes to optimise light absorption and downstream electron flow and iii. how the cellular organelles interact to optimise CO2 assimilation via ATP/NADPH exchanges.In the second part, I have focused on the regulation of light harvesting and dissipation in Chlamydomonas by studying the role of perception of light colour and metabolism on excess light dissipation via the Non-Photochemical Quenching of energy (NPQ). Using biochemical and spectroscopic approaches, I found a molecular link between photoreception, photosynthesis and photoprotection in Chlamydomonas via the role of the photoreceptor phototropin on excess absorbed energy dissipation (NPQ) and also demonstrated that besides light, downstream metabolism can also affect this acclimation process.Overall this Ph.D work reveals the existence and integration of different signal pathways in the regulation of photoprotective responses by microalgae living in the ocean and in the land
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Keil, Claudia. "Physiologie nährstofflimitierter Bakterien in Membranbioreaktoren." Clausthal-Zellerfeld Papierflieger, 2007. http://d-nb.info/985706538/04.
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Labouret-Grare, Mireille. "L'aristocrate balzacienne : physiologie et poétique." Paris 4, 1988. http://www.theses.fr/1988PA040040.
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Le type de l'aristocrate balzacienne obéit à la double postulation des contraires et des similaires. Son corps exprime la tension entre nature et culture: à la mondaine toujours en scène, emblème d'une caste et d'une époque donnée, répond la femme naturelle qui participe des éléments primordiaux, eau, terre, feu. Aussi les métaphores angéliques et animales qui la caractérisent traduisent cette hantise de la "femme en deux volumes" et abolissent la frontière entre grande dame et femme vénale. La présence du corps aristocratique, modèle absolu pour les autres femmes de la comédie humaine, s'affirme dans le portrait, non plus envisagé comme élément autonome, mais ouvert sur l'ensemble du texte romanesque. Cette remise en cause de la synchronie du portrait suppose que soient pris en compte le langage du corps et les fonctions qui le structurent. A mesure que s'élabore ce type balzacien, se dessinent l'aspiration au sublime et la prise de distance ironique; le sublime de la faute et du visage marque la genèse de l'aristocrate qui subit une série de dégradations avant de disparaitre, laissant à d'autres personnages exceptionnels le soin d'incarner la dernière image du sublime balzacienThe classic example of the balzacian aristocratic woman is characterized by the double law of opposites and similarities. Her body expresses the tension between nature and culture. The fashionable woman, always acting, symbolizing a precise caste and time, counterpoises the natural woman who partakes of the essential elements: water, earth and fire. So, the angelic and beastly metaphors which characterize her convey this obsession of the "double sided woman" and abolish the differences between a great lady and a prostitute. The presence of the aristocratic woman's body, a paragon of beauty for the other women in la comédie humaine, is asserting itself in the portrait, no longer considered as an autonomous element but open onto the whole fiction. This calling into question of the synchrony of the portrait implies that the language of the body and the functions which structure it should be taken into account. As that classic example is building up, the longing for the sublime and the ironic distanciation are taking shape. The sublime of the sin and the face stresses the genesis of the aristocratic woman who undergoes a series of degradations before vanishing, leaving it to other exceptional characters to embody the last image of the balzacian sublime
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Labouret-Grare, Mireille. "L'Aristocratie balzacienne, physiologie et poétique." Lille 3 : ANRT, 1989. http://catalogue.bnf.fr/ark:/12148/cb37614835d.
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Clearwater, Susan Jane. "The reproductive physiology of yellowtail flounder, Pleuronectes ferrugineus, with an emphasis on sperm physiology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0007/NQ36202.pdf.
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Brun, Julien. "Le problème de la musique dans la philosophie de Nietzsche." Thesis, Reims, 2011. http://www.theses.fr/2011REIML007.
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Le présent travail de recherche développe l’hypothèse selon laquelle la réflexion de Nietzsche sur la musique soulève un problème spécifique, le problème de la musique, en le subordonnant à une problématique générale qui gouverne l’ensemble de son questionnement philosophique, la problématique de la culture. Il a pour enjeu de montrer de quelle manière les textes sur la musique distribués tout au long de l’oeuvre de Nietzsche contribuent à l’élaboration et à la réalisation du programme philosophique destiné à répondre à cette problématique originale, qui fait du philosophe un « médecin de la culture ». La méthode mise en oeuvre consiste à lire dans leur intégralité et dans leur contexte la plupart des textes retenus, afin de restituer simultanément leur cohérence interne et leur fonction dans l’oeuvre de Nietzsche. Le plan s’efforce de suivre le leitmotiv de la thèse : la première partie retrace l'hypothèse, la méthode et l'enjeu du questionnement de Nietzsche à partir des textes programmatiques dans lesquels il expose sa pratique philosophique, en essayantd’expliquer la logique d'écriture qui lui est propre ; la deuxième partie étudie l’application de cette hypothèse et de cette méthode à l’art et à l’esthétique à partir des textes qui synthétisent les principaux résultats de ses analyses, en essayant de préciser leur enjeu déterminant pour l’expérience de pensée de Nietzsche ; la troisième partie propose un commentaire suivi et détaillé d’un large choix de textes consacrés à la musique, en essayant de démontrer leur inscription dans le programme opératoire du « médecin de la culture »This research work develops the hypothesis that Nietzsche's thinking on music raises a specific problem, the problem of music, by subordinating it to a general issue that governs his whole philosophical questioning, the issue of culture. The purpose of the thesis is to show how Nietzsche's texts on music, throughout his works, participate in the development and achievement of the philosophical program designed to respond to that original issue, which makes the philosopher a "physician of culture". The implemented method consists in reading most of the selected texts in their entirety and context, in order to render simultaneously their proper consistency and their function into Nietzsche’s works. The outline strives to follow the leitmotiv of the thesis: the first part sets out the hypothesis, method and goal of Nietzsche’s questioning by reading the programmatic texts in which he describes his philosophical practice and tries to explain his own logic ofwriting ; the second part studies the application of this hypothesis and method to both art and aesthetic by reading texts that summarize its main results and tries to specify the defining valence of this analyses for Nietzsche’s experience of thinking ; the third part offers a comprehensive and detailed commentary of a wide selection of texts dedicated to music and tries to demonstrate their inscription into the operating program of a "physician of culture”
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Bain, Anthony R. "Physiology of extreme breath-holding." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58424.
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The practice of competitive breath-hold (apnea) diving has provided a gateway for studying the physiologic limits of severe hypoxemia and hypercapnia beyond otherwise possible in healthy humans. In elite apnea competitors, the broad objectives of this Thesis were to, a) quantify the impact of peripheral and central chemoreception, and lung volume on the elite dry-land apnea breakpoint, and b) examine the consequences of prolonged apnea on the cerebral metabolic functioning. These objectives were achieved in four experimental studies. Study 1 explored the impact of peripheral chemoreflex silencing with low-dose dopamine. Here, compared to placebo, dopamine blunted the ventilatory response to hypercapnic-hypoxia by ~27%; however, maximal apnea duration was only increased by ~5%. At the breakpoint, arterial hypoxemia was identical with dopamine compared to placebo, indicating that the apnea termination may largely be determined by a threshold level of hypoxemia to maintain consciousness. To eliminate the influence of hypoxia, Study 2 assessed the main determinants of an apnea breakpoint following hyperoxic pre-breathing. Here, the apnea duration was related to the individual forced vital capacity, and unrelated to the central chemoreflex. Respiratory muscle fatigue and pending atelectasis likely determined the capacity of a maximal hyperoxic apnea. Study 3 quantified the cerebral metabolism during apnea. The cerebral metabolic rate of oxygen, measured from the product of cerebral blood flow and the radial artery-jugular venous oxygen content difference, was reduced by ~29% at the termination of apnea. However, there was no change in the cerebral non-oxidative metabolism, calculated from the ratio of oxygen and carbohydrate metabolism. Study 4 examined the cerebral metabolic response in three apneas eliciting separate levels of hypoxemia and hypercapnia. Apneas generating the most severe hypercapnia, irrespective of hypoxia, elicited the largest reduction in the cerebral metabolic rate of oxygen. Moreover, apneas generating the most severe hypoxia, irrespective of hypercapnia, caused a cerebral net release of lactate, suggesting astrocyte glycogenolysis. Together, the findings of this thesis provide new insight into the determinants of an extreme apnea breaking point, and the observations of hypercapnic-induced reduction in oxidative cerebral metabolism provides a tenable mechanism for cerebral protection against prolonged apnea.Graduate Studies, College of (Okanagan)
Graduate
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Morris, Beryl. "Physiology and taxonomy of blowflies." Title page, summary and contents only, 1993. http://web4.library.adelaide.edu.au/theses/09A/09am875.pdf.
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Schulze, Ulrik. "Anaerobic physiology of Saccharomyces cerevisiae /." Online version, 1995. http://bibpurl.oclc.org/web/20903.
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Kelsall, Angela. "Respiratory physiology in chronic cough." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491479.
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Introduction: Varying methods of cough quantification have been used to describe cough frequency, although there is no consensus which method best relates to subjective rating of cough. With increased availability of semi-automated cough recording devices, the capability to carryout anti-tussive studies is greatly increased. However, there is no data available describing the magnitude of change in cough frequency necessary to provide therapeutic benefit. Female patients are over represented in specialist cough clinics. There is little data describing pulmonary function and airway inflammation in phenotyped patients and how these measures may relate to objectively measured cough. Airway inflammation isa common feature of chronic cough, regardless of the trigger for cough. The repetitive mechanical insult of the act of coughing may be responsible for the presence ofthis inflammation. Methods: 100 patients with unexplained chronic cough under went full diagnostic testing in order to determine potential triggers for cough. Procedures included pulmonary function testing; (spirometry, eND, EBC pH, BHR, Cough challenge, induced sputum, objective and subjective cough monitoring), Bronchoscopy, 24 hour impedance monitoring with simultaneous cough monitoring, Gastroscopy and ENT. A subset of cough recordings were quantified in cough sounds, cough seconds and cough epochs to determine the best way to quantify cough. 20 healthy volunteers performed voluntary coughing manoeuvres to determine the acute effects of coughing on airway function and inflammation. Results: Cough sounds and seconds correlate moderately with subjective and QDL . methods. Patients reported a reduced cough frequency whilst undergoing impedance testing; a reduction of33% was seen although patients were unable to quantify the scale of change. Female patients coughed substantially more than male patients, with the largest difference seen at night. Cough frequency was predicted by gender, C5 and age. Cough frequency was not related to a specific trigger for cough. Reduced small airway flows were seen that were independent of BHR. Prominent airway neutrophilia was seen regardless of the trigger for cough. Acute changes in eND and EBC were seen after short periods ofvoluntary coughing. Sputum inflammatory mediator levels showed huge variability and did not change as a result of coughing. Bronchodilation ofthe small airways was also seen after coughing. Conclusion: The use of objective cough monitoring has enabled me for the first time to describe the most appropriate current methods of cough quantification and to demonstrate the magnitude ofreduction in cough frequency that is appreciated by -patients.-I-havereportedimportant significant genderdifferences in cough frequency and shown that cough frequency is predicted not only by gender but also age and cough reflex sensitivity showing important implications for underlying mechanisms of chronic cough. I have also shown for the first time that pulmonary function measures are reduced in patients without indication of asthma. The mechanical act of coughing causes acute bronchodilation of small airways and reduces eND and EBC pH.
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Rippon, Mark Geoffrey. "The physiology of wound healing." Thesis, Manchester Metropolitan University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240980.
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Slusarczyk, Adrian L. (Adrian Lukas). "Molecular imaging with engineered physiology." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104229.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biological Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 125-133).
Using molecular imaging in vivo, biomolecular and cellular phenomena can be investigated within their relevant physiological context, addressing a central challenge for 21st century biomedicine and basic research. To advance neuroscience in particular, molecular-level measurements across the brain inside the intact organism are required. However, existing imaging strategies and available probes have been limited by serious constraints. Magnetic resonance imaging (MRI) provides deeper tissue penetration depth than optical imaging and better spatial resolution and greater versatility in sensor design than radioactive probes. The most important drawback for MRI probes has been the need for high concentrations in the micromolar to millimolar range, leading to analyte sequestration, complications for noninvasive brain delivery, and toxicity. Efforts to address the sensitivity problem, such as nuclear hyperpolarization, introduce their own technical constraints and so far lack generality. Here, we introduce a conceptually novel molecular imaging technique based on artificially induced physiological perturbations, enabling molecular MRI with nanomolar sensitivity. In this imaging strategy, we take advantage of blood as an abundant endogenous source of contrast compatible with multiple imaging modalities including MRI and optical imaging to decouple the concentration requirement for molecular sensing from the concentration requirement for imaging contrast. Highly potent vasoactive peptides are engineered to respond to specific biomolecular phenomena of interest at nanomolar concentrations by inducing dilation of the microvasculature, increased local bloodflow, and consequently, large changes in T₂*-weighted MRI contrast. This principle is exploited to design activatable probes for protease activity based on the calcitonin gene-related peptide (CGRP) and validate them for brain imaging in live rats; to use CGRP as a genetic reporter for cell tracking; and to create fusions of a vasoactive peptide from flies to previously characterized antibodies capable of crossing the blood-brain barrier (BBB), suggesting the possibility of minimally invasive brain delivery of such probes. We demonstrate the feasibility of highly sensitive molecular MRI with vasoactive probes at concentrations compatible with in situ expression of probes and delivery across the BBB, and show that vasoactive peptides are a versatile platform for MRI probe design which promises unprecedented in vivo molecular insights for biomedicine and neuroscience.
by Adrian L. Slusarczyk.
Ph. D.
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Hopkins, John. "Lymphoid physiology of the sheep." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/29805.
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The aim of this thesis is to bring together and summarize the results of twenty-five years of active research into the immunology and physiology of the mammalian lymphoid system using the sheep as the model species. For this work I have exploited the cannulation of peripheral lymphatics, which enables the monitoring of lymph, lymphocytes and dendritic cells that are constantly trafficking from the skin or from lymph nodes. The use of this technique in the sheep permits access to large numbers of lymph-borne cells over extensive periods and in a form far closer to their in vivo non-activated state than from any other species. I have organized the publications into four distinct, but interrelated chapters. Chapter 1 is concerned with the physiology of sheep lymphoid cells and describes the use of the cannulated lymphatic model to answer fundamental questions of lymphoid biology. My earliest work was focused on the non-random migration of lymphocytes and the identification of two lymphocyte populations; one associated with the gastrointestinal tract and other mucosal organs and the other with peripheral lymph nodes and the spleen. Later work identified two separate populations of B cells with distinct recirculation properties and also concentrated on the lymph node response to antigen and the role played by antigen in modulating lymphocyte recirculation. Much of my work in the last few years has been concerned with the biology of dendritic cells (DCs), the cell population uniquely able to induce the primary immune response. The "pseudo-afferent" cannulation system in sheep is, arguably the best system for this study, as the isolation procedure does not lead to aberrant changes in cell phenotype and function. Chapter 2 relates the work to characterize the sheep immune system, in order to exploit further the sheep as a species for immunological study. Much of my efforts involved the production and characterization of anti-sheep MHC and CD1 monoclonal antibodies (mAbs). This resulted in the generation of monoclonal reagents that are now the standards used to define the ovine/bovine homologues of MHC class I, and class II and CD1.
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Kimura, Tetsuya. "Surface mechanomyogram for applied physiology." Kyoto University, 2007. http://hdl.handle.net/2433/136419.
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Kyoto University (京都大学)0048
新制・課程博士
博士(人間・環境学)
甲第13146号
人博第353号
新制||人||88(附属図書館)
18||D||154(吉田南総合図書館)
UT51-2007-H419
京都大学大学院人間・環境学研究科共生人間学
(主査)教授 森谷 敏夫, 教授 小田 伸午, 助教授 林 達也
学位規則第4条第1項該当
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Kadam, Priya. "Physiology of halophilic, methylotrophic methanogens /." Full text open access at:, 1996. http://content.ohsu.edu/u?/etd,652.
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Appleby, Hollie Leanne. "Orai channel physiology and pharmacology." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15950/.
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Background: Cardiovascular disease is often characterised by functional and structural changes in the blood vessel wall, usually associated with endothelial dysfunction. Therefore, interest in targeting the dysfunctional endothelial cell has heightened. Ca2+ signalling is crucial to endothelial cell physiology as it drives a number of intracellular signalling pathways. Store-operated Ca2+ entry (SOCE) mediated by Orai1 channels is of particular interest as it provides a major Ca2+ influx pathway in endothelial cells, driving cell migration and proliferation, ultimately contributing to endothelial repair and integrity, angiogenesis and wound healing events. The novel hypothesis is that modulation of Orai1 channels will have important physiological effects on endothelial cell function. Methods and Results: A novel series of Orai1 inhibitors has been identified in this thesis with improved pharmacological and physicochemical properties compared to existing SOCE inhibitors. Optimisation of compounds’ structure-activity relationships (SAR) via Ca2+ measurement assays using human umbilical vein endothelial cells (HUVECs) has revealed important insights into functionally important features of SOCE blockers. In conjunction with in silico modelling, a novel binding site in the Orai1 channel located in a small extracellular pocket has been proposed. The generation and subsequent testing of a quaternary ammonium analogue of the parent compound, JPIII supports the hypothesis. The novel SOCE inhibitors suppressed endothelial cell migration and proliferation without affecting cell viability. Reassuringly, the small molecules were well tolerated in vivo, supporting further development and testing of such blockers in animal models of cardiovascular disease. Here, a novel transgenic murine model with the potential for temporal and conditional disruption of Ca2+ permeation in Orai1 channels has been generated and characterised, offering new possibilities for better understanding of the physiological and pathological roles of Orai1 and the therapeutic potential of targeting this channel. Conclusion: Novel SOCE inhibitors have been characterised in vitro, their mechanism of action interrogated and their properties optimised for the next stages of in vivo testing in an animal model of cardiovascular disease.
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Susa, Matthew Stephen. "The Physiology of the Triathlon." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/322073.
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Eilts, J. Alexander. "The Physiology of Exploitation Competition." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195710.
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Water is a critical resource for which plants compete in many terrestrial communities. In arid communities where water most limits plant growth, rainfall events occur in discrete, pulsed events. These pulses of water create highly variable soil moisture availabilities. Plant species respond differently to variation in soil water availabilities throughout a season and between years. How species vary in their responses to a range of water availabilities is thought to influence community and ecosystem properties. Many previously proposed hypotheses are not suitable to explain rapidly fluctuating resource availabilities or numerous input events throughout the growing season. This dissertation uses variation in water availability as a model resource to examine how species characteristics influence the process of exploitation competition within plant communities.Experiments were conducted to examine variation in growing season, exploitation competition between several pairs of co-occurring species in the Sonoran desert. Three separate studies evaluated several components of community dynamics thought to be influenced by exploitation competition. Spatial attributes of exploitation competition were assessed by measuring the performance of a deep-rooted species across the boundary of a natural expansion of a shallowly rooted species. Then, neighborhood composition was varied for species of similar growth-form to address the affects of species characteristics to shifts in abundances under field conditions. Lastly, species from the neighborhood composition study were placed under controlled, manipulated water availabilities to measure their fundamental operational conditions.Performances of plant species in all experiments were assessed using a combination of physiological and vegetative measurements, capturing the responses of the plants to both the dynamic growth conditions during the growing season, and integrated measures of plant performance post growth season. A shared preference was found for all species, where the performance of all species was greatest when water was most available in the soil profile. This work suggests the mechanism within a functional type by which plants coexist at various abundances is in part due to the variation in responses to temporal resource gradients. The variation in availability of resources and the species composition within the community should be considered in studies of competition between plant species.
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Parker, Eleanor. "Mechanical loading and cartilage physiology." Thesis, University of Westminster, 2011. https://westminsterresearch.westminster.ac.uk/item/8zzqy/mechanical-loading-and-cartilage-physiology.
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Whilst mechanical impact is known to be essential for cartilage maintenance, it has been noted that altered joint loading and increased force may lead to cartilage degradation and increase the risk for the development of osteoarthritis (OA). This study investigated the cellular responses of chondrocytes to mechanical impact, and the effects of possible chondroprotective agents for OA preventative strategies in individuals exposed to high impact, repetitive loading. Single-impact mechanical trauma (force 1.14 N, pressure 6.47 KPa) was determined to induce biphasic decrease in cell volume to 647.38±60.38 μm3 at 2 h and 516.52±38.86 μm3 at 48 h, the initial phase of which was observed to be an active mechanotransduction mechanism, termed Impact-Induced Volume Decrease (IIVD), and the subsequent phase to be Apoptotic Volume Decrease (AVD). The newly defined IIVD was concluded to be dependent upon the PKC/PLCβ3 pathway, and possibly mediated by intracellular Ca2+ store release and Volume Sensitive Organic Anion Channel (VSOAC) activity. Furthermore, mechanical impact was observed to induce a rapid decrease in F-actin from 1.19±0.13 MU to 0.87±0.02 MU, termed Impact-Induced Actin Decrease (IIAD) and associated with the biphasic rise in cell death at rates of 2.75±0.41 %.h-1 and 0.66±0.03 %.h-1. Both in vivo exercise and in vitro mechanical load induced a release IL-1β (20.67±2.58 % and 5.86±0.21 AU), MCP-1 (25.69±0.53 % and 1.45±0.01 AU) and IL-10 (8.97±2.40 % and 5.55±0.28 AU), with in vivo concentrations correlating with joint magnitude and strike patterns. Decreased levels of IL-1β and MCP-1 (to 9.60±2.34 % and 9.01±2.34 %, respectively) observed in the evening were further confirmed using a hyperosmotic-treated in vitro model of prolonged static-loaded cartilage with evidence for a IL-1β-dominated paracrine loop between articular cartilage and mononuclear phagocytes. In vitro, chondroprotective and antiinflammatory actions of chondroitin sulphate, glucosamine sulphate, REV 5901 and Tamoxifen were associated with a reduction in pre-impact cell volume (average of 31.91±4.19 %) and increased pre-impact actin levels (average of 39.92±9.29 %). Anti-inflammatory agents, curcumin and dexamethasone exhibited less effective chondroprotective actions, via inhibition of IL-1β (average of 83.45±1.30 %) and thus apoptosis. To conclude, high impact exercise is recommended with a place for chondroprotective properties of chondroitin, glucosamine sulphate and/or curcumin in high-risk groups before OA onset.
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Smurzynski, Jacek. "Recent Advances in Cochlear Physiology." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/2161.
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Beloucif, Sadek. "Physiologie et physiopathologie des modifications de retour veineux induites par la ventilation (doctorat : physiologie cardio-vasculaire)." Paris 11, 1996. http://www.theses.fr/1996PA11T042.
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Jourdain, Sarah. "La flore commensale bactérienne de l'enfant: impact et prévention /cpar Sarah Jourdain." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/241300.
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Anschütz, Uta. "Physiologie und Biophysik der pflanzlichen Glutamatrezeptoren." kostenfrei, 2008. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2008/2943/.
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Scherl, Andre. "Hypermediale Wissensvernetzung in Physiologie und Physik." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-161267.
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Chung, Jack V. (Jack Vinh) 1978. "Search engine for online physiologic databases." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86654.
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Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2001.Includes bibliographical references (leaf 40).
by Jack V. Chung.
M.Eng.and S.B.
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Seroussi, Simon. "Pharmacologie de l'oméprazole et physiologie gastrique." Paris 5, 1994. http://www.theses.fr/1994PA05P015.
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Loudhaief, Rihab. "Effets des bioinsecticides à base de Bacillus thuringiensis sur la physiologie intestinale de la Drosophile." Electronic Thesis or Diss., Université Côte d'Azur (ComUE), 2016. http://theses.unice.fr/2016AZUR4054.
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Le tube digestif est la première barrière contre les agresseurs présents dans la nourriture (virus, bactéries, produits chimiques, pesticides etc...). Il doit donc maintenir au mieux son intégrité structurale et fonctionnelle tout au long de la vie de l'individu. Bien que l'impact délétère d'une intoxication aiguë puisse être surmonté par la capacité de défense et de régénération de la muqueuse digestive, une agression prolongée ou répétée peut compromettre l'équilibre physiologique (l'homéostasie) du tube digestif. Parmi les agresseurs pouvant être ingérés avec la nourriture, on trouve la bactérie Bacillus thuringiensis (Bt) et représente 70% des ventes de bioinsecticides. Bt est une bactérie Gram+ sporulante qui produit, pendant la sporulation, des toxines nommées Cry. Parmi les différentes souches de Bt, certaines ont été sélectionnées pour la spécificité d'action de leurs toxines Cry contre des nuisibles et sont commercialisées sous forme de sporanges. Certaines de ces souches sont utilisées en agriculture biologique en France et l'accroissement de leur utilisation fait qu'elles sont de plus en plus présentes dans la nourriture, source de contamination potentielle pour l'homme et l’environnement. La question qui se pose maintenant est de savoir si un tel accroissement de l’utilisation de Bt peut avoir des impacts sur des espèces non cibles. Mon projet de thèse a consisté en l’étude des conséquences de l'ingestion de Bt (sous forme végétative ou de sporanges) sur la physiologie intestinale de la drosophile (animal non sensible à Bt en termes de toxicité aigüeThe digestive tract is continuously subjected to multiple aggressions through virus, bacteria, toxins and chemicals mixed in the feed. Therefore the gut lining has established a mechanism of replenishment in order to maintain the physiological function of the organ called the gut homeostasis. Although the deleterious impact of acute poisoning can be overcome by the defense capacity and regeneration of the gut mucosa, prolonged or repeated intoxication can impair its homeostasis. Among the aggressors hidden in the feed, there is the bacterium Bacillus thuringiensis (Bt). Bt is worldwide used as bioinsecticide. Indeed the multitude of Bt strains produces a broad range of crystalline toxins, named Cry toxins, which certain have been selected in organic farming owing to their lethal properties against specific pests. Because of incentive programs for sustainable development, the use of Bt bioinsecticides as an alternative to chemical pesticides will further increase in the next decades. Although the specificity of the acute toxicity of Cry toxins has been proved since many years, data are scarce on adverse effects that could result from chronic exposure. The question now is how far non-target organisms will be potentially impacted by the resulting augmentation of the Bt bacterium and its Cry toxins in the environment. To answer this challenge, I used Drosophila (a non-target organism) to study the impacts of Bt bioinsecticides on the gut physiology because 1/ the digestive tract is the main entrance for feed contaminated by Bt bioinsecticides and 2/ Bt and its toxins are known to impair the gut epithelium of sensitive pests
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Fôch-Gatrell, Siân. "Nanophytoplankton physiology and the carbon cycle." Thesis, University of East Anglia, 2015. https://ueaeprints.uea.ac.uk/59615/.
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Laboratory experiments on the physiological response of members of the nanophytoplankton to temperature and light limitation and nutrient saturation were conducted in order to investigate if nanophytoplankton conforms to Plankton Functional Types (PFTs) for modelling purposes. This thesis concluded that nanophytoplankton does not follow all of the assumed physiological traits. The Q10 estimates for members of the nanophytoplankton are considerably lower than Eppley, and since nanophytoplankton does not follow the Eppley curve at warmer temperatures, the results suggest that the Eppley assumptions cannot be used to describe nanophytoplankton. μmax0 is used as a temperature physiological modelling parameter (as well as Q10) which are components of the exponential and linear fits. However, nanophytoplankton best fits to an optimum function which uses μopt, Topt and dT as model parameters. These results are in contrast to the Eppley assumptions. Using a dynamic photosynthesis model five phytophysiological parameters were derived including the maximum photosynthesis rate (Pcm,), respiration rate (resp), the initial slope of the line (achl), light inhibition (βchl) and the maximum chlorophyll to carbon ratio (θmax). These parameters were estimated using an acclimated model which used the instantaneous rates of photosynthesis to estimate the other parameters. The acclimated model gave the best fit (AIC = -3.75 vs. = -0.95). These results are in contrast to those used for PFT modelling purposes. Parameters are comparable for Pcm, resp and θmax but showed significant differences for αchl and βchl the latter of which was underrepresented in the dynamic model, and the former of which is used as a model parameter for PFT parameterization. Chlorophytes had stronger light inhibition (mean βchl= 0.72 g C m2 (mol photons g Chl α)-1) than haptophytes (mean βchl = 0.34 g C m2 (mol photons g Chl α)-1). βchl is significantly lower for haptophytes (P = 0.002). Members of the nanophytoplankton showed relatively high μmax (0.81 d-1 from the acclimated model fit) and mean photosynthesis rates 1.8 Pcm (d-1) mean cell volume 37 μm3). Maximum growth rates increased with increasing cell volume for all of the species. Members of the nanophytoplankton alter their elemental stoichiometry and assimilated nutrients in excess of their requirements but as a PFT, there were no statistically significant deviations from Redfield. Under nutrient replete conditions Chl α:C increased linearly with increasing temperature and increased linearly with decreasing light. Overall, these results suggest that further physiological data is required in order to parameterize models to estimate nanophytoplankton physiological responses to climate change.
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Clements, M. R. "The physiology economy of vitamin D." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47002.
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Moser, Jonathan G. "Cold Season Physiology of Arctic Plants." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/750.
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The cold season in the Arctic extends over eight to nine months during which ecosystem gas exchange and water balance of arctic plants have been largely unexplored. The overall objective of this thesis was to examine two critical gaps in our knowledge about tundra cold season processes – ecosystem respiration at very low temperatures and water uptake during the winter-spring transition. I determined the temperature response of ecosystem respiration of tundra monoliths down to temperatures as low as can be expected under snow-covered conditions (-15 °C). Temperature responses fit the Arrhenius function well with Q10 values over the range of -15 to 15 °C varying from 6.1 to 4.8. I used deuterium-enriched water (2H2O) as a tracer to evaluate water uptake of evergreen plants at snowmelt when soils are largely frozen. The results revealed that evergreen plants take up water under snow cover, possibly via roots but undoubtedly by foliar uptake.
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Williams, Rupert Philip Charles. "Coronary physiology of the stressed heart." Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/coronary-physiology-of-the-stressed-heart(a6f0e19d-b6fe-4ced-a37c-181d5266ae69).html.
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Background Highest rates of exertion related cardiac death occur during cold air inhalation (CAI): e.g. shovelling snow, but the pathophysiology is unclear. Coronary micro-vascular resistance (MVR) is the major factor regulating coronary blood flow and subsequent myocardial perfusion. Patients with significant coronary artery disease may be more prone to adverse events due to a reduced vasodilator reserve. Novel intracoronary wires, that simultaneously measure coronary artery pressure (Pd) and coronary blood flow (CBF) allow quantification of MVR, enabling physiological investigation of the effects of CAI during exercise. Study 1. hMR versus IMR at predicting microvascular dysfunction. We compared headto- head, the diagnostic accuracy of the two available invasive indices of MVR, Dopplerderived hyperaemic microvascular resistance (hMR) versus thermo-dilution-derived index of microcirculatory resistance (IMR), at predicting microvascular dysfunction. We then used the most accurate measure of MVR in Study 2. Study 2. Cold air with and without exercise on MVR in CAD patients. We explored the effects of CAI alone and during exercise on MVR and CBF in patients with significant coronary artery disease. Methods Study 1. 56 patients (61 ± 10 years) undergoing cardiac catheterisation for stable coronary artery disease or acute myocardial infarctions (AMI) were recruited. Simultaneous intracoronary pressure, Doppler flow velocity and thermodilution were carried out in 74 vessels without obstructive epicardial disease, at rest and during hyperaemia. In the absence of a gold-standard, the following three measures of microvascular dysfunction were used, using a pre-defined dichotomous threshold for each parameter: 1) Mean coronary flow reserve (CFRmean), defined as the average value of Doppler and thermodilution derived coronary flow reserve 2) Cardiac Magnetic Resonance (CMR) defined myocardial perfusion reserve index (MPRI) 3) CMR defined extensive microvascular obstruction (MVO). Study 2. 35 patients (62 ± 9 years) with significant coronary artery stenoses who were undergoing coronary angiography were allocated to 5 minutes of either: 1. CAI (-15oC), n=10 2. Exercise (Incremental supine ergometry), n=24 3. Exercise with CAI, n=13. (12 patients did both conditions 2. and 3., and for these patients the order was randomised). Forty seven datasets were obtained in total. We compared rest and peak measurements of Doppler-derived MVR (Pd/CBF) and CBF. We also used wave intensity analysis to identify waves that accelerate and decelerate CBF, and calculated the proportional contribution of accelerating waves as a coronary perfusion efficiency index. Results Study 1. hMR had better diagnostic accuracy than IMR to predict CFRmean (area under curve, (AUC) 0.82 versus 0.58, p < 0.001, sensitivity/specificity 77/77% versus 51/71%) and MPRI (AUC 0.85 versus 0.72, p=0.19, sensitivity/specificity 82/80% versus 64/75%). In AMI patients, the AUCs of hMR and IMR at predicting extensive MVO were 0.83 and 0.72 respectively (p=0.22, sensitivity/specificity 78/74% versus 44/91%). Study 2. MVR increased during CAI alone, whereas MVR decreased during exercise. Exercise with CAI was associated with less decrease in MVR. The increase in CBF was similarly less during exercise with CAI versus without. Coronary perfusion efficiency increased during exercise. However the addition of CAI during exercise abolished this. Conclusion Study 1. In our study cohort Doppler-derived hMR had superior diagnostic accuracy over IMR at predicting several invasive and non-invasive measures of microvascular function. This measure was therefore used to measure MVR in Study 2. Study 2. In CAD patients CAI substantially attenuated the reduction in MVR and the increase in CBF that normally occur during exercise. Moreover, while the heart has improved coronary perfusion efficiency during exercise, this may be attenuated when exercise is combined with CAI. This suggests that CAI during exercise may impede coronary vasodilatation and ventricular relaxation, rendering the heart more susceptible to ischaemia. Complementary studies (Studies 3 and 4) were performed in the absence of invasive measures of central and coronary haemodynamics to examine the differential effects of isometric and dynamic exercise (Study 3) and that of first and second exercise efforts (Study 4).
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Kamath, Osler C. "Physiology and control of apple scald." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03122009-040821/.
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