Teses / dissertações: "Suppression de la graisse"

1

Josset, Anne. "Suivi par thermométrie par imagerie par résonance magnétique (IRM) des ablations thermiques dans les tissus mous". Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAD040.

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Les ablations thermiques constituent des alternatives prometteuses aux techniques conventionnelles, notamment pour le traitement de cancers. Le caractère minimalement invasif de ces thérapies contribue à réduire la morbidité et les effets secondaires, transformant ainsi la prise en charge des patients. Toutefois, cela nécessite l’utilisation d’outils appropriés pour un suivi en temps réel des thérapies afin d’attester un traitement efficace et d’assurer la sécurité de la procédure. La thermométrie par Imagerie par Résonance Magnétique (IRM) est reconnue comme le gold standard pour monitorer ces thérapies. En effet, cette technique d’imagerie non invasive permet de cartographier de façon précise les changements de température au sein des tissus aqueux grâce à la méthode de la PRFS (Proton Resonance Frequency Shift). Cependant, l’efficacité de cette méthode, en particulier dans les tissus contenant de la graisse, nécessite une évaluation précise. Dans le cadre de ce travail de thèse, nous avons mis au point une méthode pour quantifier les pics restants de la graisse après différentes méthodes de suppression de la graisse. Cette approche a été caractérisée lors d’expériences in vitro et in vivo. La précision des mesures de thermométrie IRM PRFS a été ensuite mesurée pour plusieurs quantités de gras avec différentes méthodes de suppression. Les résultats montrent que le signal résiduel de la graisse impacte les mesures de température IRM PRFS. Une méthode a alors été proposée pour évaluer les variations de température sans suppression de la graisse à l’aide d’un algorithme de séparation de l’eau et de la graisse. L’approche proposée est compatible avec des séquences rapides, adaptées au temps réel, et permet de mesurer avec précision les variations de température dans les tissus contenant de la graisse
Thermal ablation offers a promising alternative to traditional cancer treatment techniques, particularly due to its minimally invasive feature, which reduces morbidity and side effects. However, it requires the use of appropriate tools for real-time temperature monitoring to attest the effectiveness of the treatment and ensure the safety of the procedure. Magnetic Resonance Imaging (MRI) thermometry is recognized as the gold standard for this purpose, allowing for precise temperature mapping in aqueous tissues using the PRFS (Proton Resonance Frequency Shift) method. Nevertheless, the effectiveness of this method in fat-containing tissues requires careful evaluation. In this thesis, we developed a method to quantify the remaining fat peak signal after various fat suppression methods. This approach was assessed through both in vitro and in vivo experiments. We then evaluated the accuracy of PRFS MRI thermometry with several amounts of fat and different fat suppression methods. Our findings indicate that the residual fat signal impacts PRFS MRI temperature measurements. Consequently, a method was suggested to evaluate temperature variations without fat suppression techniques, using a water/fat separation algorithm. This approach is compatible with real-time sequences and enables accurate measurement of temperature variation in fat-containing tissues

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2

Poujol, Julie. "Techniques d'acquisitions et reconstructions IRM rapides pour améliorer la détection du cancer du sein". Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0143/document.

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Le cancer du sein est aujourd’hui le cancer le plus fréquent chez la femme ainsi que la première cause de décès féminin par cancer. Actuellement, l’IRM mammaire n’est réalisée qu’en seconde intention lorsque les autres modalités d’imagerie ne suffisent pas à poser un diagnostic. Dans le cas des populations à risque, l’IRM mammaire est recommandée comme examen de dépistage annuel en raison de sa très haute sensibilité de détection. Par IRM, la détection d’un cancer du sein se fait à la suite de l’injection d’un produit de contraste qui permet de visualiser les lésions mammaires en hypersignal. La majeure partie du diagnostic repose sur l’analyse morphologique de ces lésions ; une acquisition hautement résolue spatialement est donc nécessaire. Malgré l’utilisation des techniques d’accélération courantes, le volume de données à acquérir reste important et la résolution temporelle de l’examen d’IRM mammaire est aujourd’hui aux alentours d’une minute. Cette faible résolution temporelle limite donc intrinsèquement la spécificité de l’examen d’IRM mammaire. Un examen avec une haute résolution temporelle permettrait l’utilisation de modèles pharmacocinétiques donnant accès à des paramètres physiologiques spécifiques des lésions. L’approche proposée dans ce travail de thèse est le développement d’une séquence IRM permettant à la fois la reconstruction classique d’images, telle que celle utilisée en routine clinique pour le diagnostic, ainsi qu’une reconstruction accélérée d’images avec une plus haute résolution temporelle permettant ainsi l’application de modèles pharmacocinétiques. Le développement de cette séquence a été réalisé en modifiant l’ordre d’acquisition du domaine de Fourier de la séquence utilisée en clinique, afin qu’il soit aléatoire et permette la reconstruction a posteriori de domaines sous-échantillonnés acquis plus rapidement. Des acquisitions sur des objets tests, sur des volontaires et sur des patientes ont montré que l’acquisition aléatoire ne modifiait pas les images obtenues par reconstruction classique permettant ainsi le diagnostic conventionnel. Une attention particulière a été portée pour permettre la suppression de graisse nécessaire à l’acquisition des images d’IRM mammaire. Les reconstructions des domaines sous-échantillonnés sont réalisées via des reconstructions Compressed Sensing permettant la suppression des artéfacts de sous-échantillonnage. Ces reconstructions Compressed Sensing ont été développées et testées sur des fantômes numériques reproduisant des IRMs mammaires. Le potentiel de cette nouvelle acquisition a enfin été testé sur une lésion artificielle mammaire, développée à cet effet, et reproduisant des prises de contraste mammaires
Breast cancer is nowadays the first cause of female cancer and the first cause of female death by cancer. Breast MRI is only performed in second intention when other imaging modalities cannot lead to a confident diagnosis. In high risk women population, breast MRI is recommended as an annual screening tool because of its higher sensitivity to detect breast cancer. Breast MRI needs contrast agent injection to visualize enhancing lesions and the diagnosis is mostly based on morphological analysis of these lesions. Therefore, an acquisition with high spatial resolution is needed. Despite the use of conventional MRI acceleration techniques, the volume of data to be acquired remains quite large and the temporal resolution of the exam is around one minute. This low temporal resolution may be the cause of the low specificity of breast MRI exam. Breast MRI with higher temporal resolution will allow the use of pharmacokinetic models to access physiological parameters and lesion specifications. The main aim of this work is to develop a MRI sequence allowing a flexible use of the acquired data at the reconstruction stage. On the one hand, the images can be reconstructed with a conventional reconstruction like the protocol used in clinical routine. On the other hand, the new MRI sequence will also allow the reconstruction of images with a higher temporal resolution allowing the use of pharmacokinetic models. The development of this sequence was done by modifying the acquisition order in the Fourier domain. A random acquisition of the Fourier domain will allow the reconstruction of sub-sampled domains acquired faster. We paid attention to fat suppression efficiency with this new Fourier domain acquisition order. Tests were performed on phantom, female volunteers and patients. These tests showed that the random acquisition did not impact the quality of images (MRI signal and lesion morphology) obtained by conventional reconstruction thus allowing the conventional diagnosis. The reconstructions of the sub-sampled Fourier domains were made using Compressed Sensing reconstructions to remove sub-sampling artifacts. These reconstructions were developed and tested on digital phantoms reproducing breast MRI. The potential of this new MRI acquisition was tested on an artificial enhancing breast lesion developed especially for this purpose

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3

Poujol, Julie. "Techniques d'acquisitions et reconstructions IRM rapides pour améliorer la détection du cancer du sein". Electronic Thesis or Diss., Université de Lorraine, 2017. http://www.theses.fr/2017LORR0143.

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Le cancer du sein est aujourd’hui le cancer le plus fréquent chez la femme ainsi que la première cause de décès féminin par cancer. Actuellement, l’IRM mammaire n’est réalisée qu’en seconde intention lorsque les autres modalités d’imagerie ne suffisent pas à poser un diagnostic. Dans le cas des populations à risque, l’IRM mammaire est recommandée comme examen de dépistage annuel en raison de sa très haute sensibilité de détection. Par IRM, la détection d’un cancer du sein se fait à la suite de l’injection d’un produit de contraste qui permet de visualiser les lésions mammaires en hypersignal. La majeure partie du diagnostic repose sur l’analyse morphologique de ces lésions ; une acquisition hautement résolue spatialement est donc nécessaire. Malgré l’utilisation des techniques d’accélération courantes, le volume de données à acquérir reste important et la résolution temporelle de l’examen d’IRM mammaire est aujourd’hui aux alentours d’une minute. Cette faible résolution temporelle limite donc intrinsèquement la spécificité de l’examen d’IRM mammaire. Un examen avec une haute résolution temporelle permettrait l’utilisation de modèles pharmacocinétiques donnant accès à des paramètres physiologiques spécifiques des lésions. L’approche proposée dans ce travail de thèse est le développement d’une séquence IRM permettant à la fois la reconstruction classique d’images, telle que celle utilisée en routine clinique pour le diagnostic, ainsi qu’une reconstruction accélérée d’images avec une plus haute résolution temporelle permettant ainsi l’application de modèles pharmacocinétiques. Le développement de cette séquence a été réalisé en modifiant l’ordre d’acquisition du domaine de Fourier de la séquence utilisée en clinique, afin qu’il soit aléatoire et permette la reconstruction a posteriori de domaines sous-échantillonnés acquis plus rapidement. Des acquisitions sur des objets tests, sur des volontaires et sur des patientes ont montré que l’acquisition aléatoire ne modifiait pas les images obtenues par reconstruction classique permettant ainsi le diagnostic conventionnel. Une attention particulière a été portée pour permettre la suppression de graisse nécessaire à l’acquisition des images d’IRM mammaire. Les reconstructions des domaines sous-échantillonnés sont réalisées via des reconstructions Compressed Sensing permettant la suppression des artéfacts de sous-échantillonnage. Ces reconstructions Compressed Sensing ont été développées et testées sur des fantômes numériques reproduisant des IRMs mammaires. Le potentiel de cette nouvelle acquisition a enfin été testé sur une lésion artificielle mammaire, développée à cet effet, et reproduisant des prises de contraste mammaires
Breast cancer is nowadays the first cause of female cancer and the first cause of female death by cancer. Breast MRI is only performed in second intention when other imaging modalities cannot lead to a confident diagnosis. In high risk women population, breast MRI is recommended as an annual screening tool because of its higher sensitivity to detect breast cancer. Breast MRI needs contrast agent injection to visualize enhancing lesions and the diagnosis is mostly based on morphological analysis of these lesions. Therefore, an acquisition with high spatial resolution is needed. Despite the use of conventional MRI acceleration techniques, the volume of data to be acquired remains quite large and the temporal resolution of the exam is around one minute. This low temporal resolution may be the cause of the low specificity of breast MRI exam. Breast MRI with higher temporal resolution will allow the use of pharmacokinetic models to access physiological parameters and lesion specifications. The main aim of this work is to develop a MRI sequence allowing a flexible use of the acquired data at the reconstruction stage. On the one hand, the images can be reconstructed with a conventional reconstruction like the protocol used in clinical routine. On the other hand, the new MRI sequence will also allow the reconstruction of images with a higher temporal resolution allowing the use of pharmacokinetic models. The development of this sequence was done by modifying the acquisition order in the Fourier domain. A random acquisition of the Fourier domain will allow the reconstruction of sub-sampled domains acquired faster. We paid attention to fat suppression efficiency with this new Fourier domain acquisition order. Tests were performed on phantom, female volunteers and patients. These tests showed that the random acquisition did not impact the quality of images (MRI signal and lesion morphology) obtained by conventional reconstruction thus allowing the conventional diagnosis. The reconstructions of the sub-sampled Fourier domains were made using Compressed Sensing reconstructions to remove sub-sampling artifacts. These reconstructions were developed and tested on digital phantoms reproducing breast MRI. The potential of this new MRI acquisition was tested on an artificial enhancing breast lesion developed especially for this purpose

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4

Beaujeux, Rémy. "Spécificité, fonction et imagerie de la graisse épidurale lombaire postérieure". Université Louis Pasteur (Strasbourg) (1971-2008), 1994. http://www.theses.fr/1994STR11419.

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5

Abdesselam, Inès. "Dépôts de graisse ectopique : étude de leur développement et de leur modulation". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5005.

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Le projet de cette thèse porte sur le développement de dépôts lipidiques ectopique et leur modulation suite à des intervenions thérapeutiques par imagerie résonance magnétique.Dans notre première étude, nous avons établi l’ordre chronologique d’apparition de graisses ectopiques et d’anomalies cardiaques dans un modèle de souris soumises à un régime riche en graisse et en sucre. Un traitement de courte durée à l’exendine-4 permet une amélioration de tous les paramètres altérés. Dans la deuxième étude, nous avons évalué l’impact d’un traitement de l’obésité sur les dépôts ectopique de graisse cardiaque (TAE et stéatose), hépatique et pancréatique à deux temps (6 mois et 32 mois) après chirurgie bariatrique. Nous avons montré que ce traitement chirurgical permet une réduction de tous ces dépôts, avec une cinétique différente. Enfin, dans la troisième étude, nous nous sommes intéressés à l’effet du poids de naissance sur le développement de tissu adipeux épicardique. Cette étude nous a permis de mettre en évidence qu’il existe une accumulation plus importante de TAE à l’âge adulte lorsque le poids de naissance est augmenté ; et que les paramètres poids de naissance et croissance entre 2 et 12 ans, jouent un rôle important dans la mise en place de ce dépôts de graisse ectopique. En somme, ces résultats permettent une avancée dans la compréhension du développement des dépôts de graisses et de leur modulation
The project of this thesis mainly focuses on ectopic lipid deposition development and their flexibility following therapeutic intervention. In our first study, we set out chronological order of ectopic fat onset and cardiac abnormalities in a high fat high sucrose mice model. Short duration exendin-4 treatment reverses every altered parameter. In the second study, we assessed treatment of obesity effect on cardiac ectopic fat deposition (EAT and steatosis), as well as hepatic and pancreatic fat at two different time points (6 months and 32 months) after bariatric surgery. We show significant reduction of every ectopic fat deposition, however in different kinetic. Finally, in a third study, we investigate birth weight effect on epicardial adipose tissue development. This study demonstrate important EAT accumulation in adulthood when birth weight is increased. Furthermore, birth weight and catch up growth in childhood between 2 and 12 years parameters impact significantly the development of epicardial fat.In summary, these results provide better understanding of ectopic fat deposition development and modulation

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6

JACOBERGER, BERNADETTE. "Diffusion dans la graisse epiploique de differentes familles d'antibiotiques utilisees en antibioprophylaxie". Strasbourg 1, 1992. http://www.theses.fr/1992STR15060.

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7

Balouet, Pierre. "Estimation du poids foetal : intérêt de la mesure de la graisse des membres". Caen, 1991. http://www.theses.fr/1991CAEN3055.

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8

Wilkinson, Ryan John Paul. "Effect of glucose on the suppression and post-suppression rebound of stereotypes". Thesis, University of Canterbury. Psychology, 2011. http://hdl.handle.net/10092/6213.

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The suppression of unwanted thoughts is an effortful process. An ironic effect of this process is that the unwanted thoughts can become hyper-accessibility after a period of their suppression, known as “post-suppression rebound”. In the present study the impact of providing energy (through a glucose drink) on post-suppression rebound was investigated. One hundred and twenty participants participated in the main study, and another 30 participants served as a baseline group. Half of the participants in the main study were given a drink containing glucose and the other half was given a placebo drink containing an artificial sweetener. All participants wrote a passage about a “day in the life” of a gay male, with half the participants directed to avoid using stereotypes. A subsequent lexical decision task measured activation of stereotypes. Finally, a measure of prejudice was given to account for individual differences. Neither the direction to avoid using stereotypes nor the glucose resulted in lower stereotypicality of the “day in life” passages. Furthermore, response times during the lexical decision task did not differ between any of the main conditions or the baseline condition. However, the combination of both glucose and directed suppression did result in more positive passages, suggesting that the combination assists in reducing negative stereotype usage. Results are discussed in terms of stereotype usage and suppression and prejudice level.

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9

Beaudin, Gilles. "L'anhydrase carbonique III du muscle squelettique humain". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31676.pdf.

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10

Degrace, Pascal. "Nature et origine des acides gras constitutifs des lipides des lipoprotéines de la lymphe intestinale. Etude en périodes interprandiale et postprandiale chez le rat préalablement soumis à différents régimes hyperlipidiques de longue durée". Dijon, 1997. http://www.theses.fr/1997DIJOS030.

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Des rats sont soumis pendant 4 semaines, soit à un régime normolipidique standard soit à des régimes hyperlipidiques contenant 15% d'huile de tournesol, d'huile de menhaden ou d'huile MCT. Nous avons déterminé la composition en acides gras de la lymphe, de la bile et du sang, ainsi que du tissu adipeux et du foie. Les acides gras caractéristiques des régimes et ceux dérivant de leur métabolisme hépatique apparaissent à différents niveaux de l'organisme et particulièrement au niveau des phospholipides biliaires et dans le plasma. Afin de déterminer si les régimes influent sur l'absorption intestinale des acides gras, nous avons analysé la lymphe après avoir infusé intraduodénalement aux animaux une émulsion contenant 90 moles de lipides dont les acides oléique et arachidonique marqués. L'accoutumance aux régimes tournesol et menhaden conduit à une augmentation de la quantité d'acides gras dans la lymphe après infusion de l'émulsion lipidique. Ce résultat semble être la conséquence d'une production importante de phospholipides biliaires, source d'acides gras endogènes participant à la synthèse des composants lipidiques des lipoprotéines intestinales. Au contraire, l'accoutumance au régime hyperlipidique MCT semble inhiber la sécrétion des phospholipides biliaires, diminuer la quantité d'acides gras lymphatiques, et vraisemblablement augmenter l'absorption des acides gras à longue chaine par la voie portale mésentérique. Dans le but d'évaluer les capacités d'absorption de l'intestin des animaux soumis aux différents régimes, des études concernant l'expression du fatty acid transporter (fat) et de la liver fatty acid binding protein (l-fabp) ont été réalisées. Des modifications morphologiques et fonctionnelles de l'intestin, relatives à la nature et a la quantité des acides gras exogènes et endogènes atteignant les enterocytes et susceptibles de modifier les capacités d'absorption, apparaissent après 4 semaines de régime.

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11

JACOBERGER, BERNADETTE. "Diffusion d'antibiotiques utilises en antibioprophylaxie de chirurgie digestive (doctorat : sciences pharmaceutiques)". Strasbourg 1, 1999. http://www.theses.fr/1999STR15113.

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12

Vial, Guillaume. "Métabolisme hépatocytaire et insulinorésistance : effets d'un régime enrichi en graisse et d'un nouvel antidiabétique "E008"". Phd thesis, Grenoble 1, 2009. http://www.theses.fr/2009GRE10269.

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Avec une prévalence en constante augmentation, le diabète de type II est devenu un réel enjeu de santé publique. Cette pathologie se caractérise par une hausse de la production hépatique de glucose, reflet d'une néoglucogenèse accrue qui évoluera en hyperglycémie chronique. Le foie est donc un tissu-cible privilégié pour lutter contre les déséquilibres du métabolisme glucidique. Une nouvelle drogue dérivée de la Metformine et dénuée d'effets secondaires, le E008, a été synthétisée par Merck-Santé pour normaliser la glycémie des sujets diabétiques. Le double objectif de notre travail a consisté à (i) étudier les modifications des flux métaboliques au niveau hépatique dans un modèle nutritionnel de rats développant un syndrome métabolique, (ii) analyser les effets de ce nouveau composé médicamenteux et tenter d'élucider ses mécanismes d'action. Le régime enrichi en graisses entraîne une hausse de la néoglucogenèse associée à des perturbations de la fonction mitochondriale : hausse des radicaux libres, inhibition de la respiration, variation du potentiel rédox. Un dénominateur commun à ces évènements pourrait être une altération mutuelle de la composition des lipides membranaires et des quinones. L'administration du nouvel agent antidiabétique E008 à des rats sous régime gras permet de réduire leur production hépatique exacerbée de glucose, en modifiant le contrôle des voies métaboliques. De plus, il induit une inhibition subtile de la respiration cellulaire en agissant à la fois sur la chaîne respiratoire et sur le système phosphorylant (complexe I inhibé et expression réduite de l'ANT). Son action est également liée à une activation de la protéine kinase AMP dépendante (AMPK), par altération des rapports des nucléotides adényliques
With a steadily increasing prevalence, type II diabetes is becoming a major public health issue. This pathology is characterized by an increase of the hepatic glucose production, reflecting a raise of gluconeogenesis, which evolves into chronic hyperglycemia. Liver is thus a privileged target to fight against imbalances of glucose metabolism. A new drug derived from the Metformin and devoid of side effects, the E008, was synthesized by Merck-Santé to normalize blood glucose levels in diabetic patients. The dual objective of our work consisted in (i) studying liver metabolic fluxes in a nutritional rat model which exhibits a metabolic syndrome, and (ii) analysing the effects of this new compound while elucidating its mechanisms of action. Animals fed a high-fat diet have an increased gluconeogenesis, associated with disturbances of the mitochondrial function: increase of ROS production, inhibition of oxygen consumption and changes in redox potential. A common denominator in these events could be a mutual alteration of the composition of membrane lipids and quinones. On rats fed with a high-fat diet, E008 treatment decreases the hepatic glucose output by modifying metabolic control. Furthermore, it induces a subtle inhibition of cellular respiration while acting, at the same time, on the respiratory chain activity and phosphorylating system. (Inhibition of complex I and ANT reduced expression). Its action is also related to an activation of AMP-activated protein kinase (AMPK), by modification of adenine nucleotides ratios

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13

Abumustafa, Nader. "Suppression of electrical discharges". Thesis, University of Liverpool, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569127.

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SF6 (Sulphur HexaFluoride) gas is exclusively used as a dielectric insulator and arc quenching medium in high voltage power networks. The electronegative properties of the gas and its ability to recombine after dissociation make it a gas of choice for high voltage equipment. However, SF 6 is a greenhouse gas and therefore research is needed to find an alternative. This thesis explores the potential of PolyTetraFluoroEthylene (PTFE) powder as a dielectric insulator. This has been deployed in a compacted form and when buoyant in air. This approach opens up new avenues for existing research related to gaseous dielectrics and current interruption through the utilisation of small particulates made from insulating materials. A detailed database, of breakdown voltage signals and high speed camera shots, has been compiled to facilitate comparative analysis of the effect of airborne polymer (e.g. PTFE) powders on breakdown voltage across different gap widths, relative to SF6. The breakdown voltage results which were obtained from experimental tests to demonstrate an effect on the voltage withstand that these airborne materials have comparable to that of SF6. Also, their ability to suppress electrical discharges between dielectric probe contacts is also demonstrated during the course of this thesis. In addition, a combined electrical/optical system has been constructed in order to investigate the relationship between airborne particle concentration and the resultant breakdown voltage between electrodes. The optical system was tested using smoke particles prior to its utilisation for powder particles. For both smoke and powder systems, chromaticity was utilised to assess changes in particle density. A model was used to interpret the optical signal and thereby estimate the concentration of airborne particles. This employs factors such as the refractive index, particle radius and essentially the ratio of the light source intensity as seen through the container with scattering particles to the intensity of the same light source seen through the same container without scattering particles.

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14

Hunt, Tony L. "Atheism the great suppression /". Theological Research Exchange Network (TREN), 2005. http://www.tren.com/search.cfm?p074-0069.

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15

du, Bois Jonathan Luke. "Adaptive fuselage response suppression". Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509767.

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16

Woods, Kristin Renee. "Death-primed memory suppression /". Read thesis online, 2008. http://library.uco.edu/UCOthesis/WoodsK2008.pdf.

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17

Carden, David Christopher Dagley John C. "Relationship of thought suppression and emotion suppression to lesbians' and gay men's levels of outness investigting the efects of chronic suppression /". Auburn, Ala, 2009. http://hdl.handle.net/10415/1802.

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18

Buyck, Dominique. "Influence de la graisse sur les mesures de vélocité et d'atténuation des ultrasons par le calcaneum". Montpellier 1, 1993. http://www.theses.fr/1993MON11041.

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19

Vadeboncoeur, Nathalie. "Quels sont les meilleurs indicateurs d'adiposité associés au profil métabolique des patients participants à un programme de prévention primaire et secondaire/réadaptation cardiaque?" Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28044/28044.pdf.

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20

Ricchetti, Giuseppe Antonio. "An examination of the suppression of IL-10 suppression of TNF in myeloid cells". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427864.

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21

Beiotice, Claire. "Thought suppression and dietary restraint". Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494533.

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22

Skrobic, Stevan. "Harmonic Suppression in Nonlinear Systems". Thesis, KTH, Tillämpad fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170394.

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23

Ie, Amanda Yen Lin. "Profiles of Everyday Thought Suppression". Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11059.

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The present research assessed whether levels of depression, anxiety and worry, obsessive-compulsive distress, and psychopathy were differentially related to distinct thought suppression profiles. As a means to achieving this goal, the Profiles of Everyday Thought Suppression (PETS) scale was constructed to measure the frequencies with which various target thoughts are suppressed. The PETS scale demonstrated good internal consistency and test-retest reliability, and scores were positively correlated with the general tendency to experience intrusions, the general tendency to suppress thoughts, neuroticism, and health complaints. Although the proportions of time people suppress thoughts was positively associated with the frequencies with which the thoughts are experienced, the strength of the associations differed across thought contents, suggesting that not all frequently experienced thoughts are invariably subject to suppression attempts. The frequency with which thoughts are generally suppressed was positively associated with overall levels of subclinical psychopathology experienced during the past month. When comparing across the various thought categories, results from multiple analytic strategies converged to suggest that specific subclinical psychopathological states are associated with particular sets of thoughts that are frequently suppressed.
Psychology

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24

Finlay, Annabelle Ruth. "Microbial suppression of Phytophthora cinnamomi". Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317116.

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Callery, James Francis. "Building Evaluation for Manual Suppression". Digital WPI, 2005. https://digitalcommons.wpi.edu/etd-theses/1156.

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Recent improvements in equipment used by firefighters has increased the value of manual suppression in buildings. However, because there is no evaluation method available, the effectiveness of manual suppression can not be incorporated into a fire safety analysis of a building. This thesis develops a method for evaluating manual suppression in buildings. he evaluation is done through an analysis of the paths through a building firefighters will use to attack a fire. The analysis considers the building, fire and fire department factors influencing progress towards teh fire. The fire attack path analysis yeilds a value relating the relative difficulty of a path.

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Starkey, Kyle Timothy. "Camp Alva: Suppression by Recreation". Youngstown State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1433251083.

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Luk, Kwok-hing R. "Quadrupolar impurity suppression of superconductivity /". The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487759914761644.

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Alban, Tyler Joseph. "TARGETING IMMUNE SUPPRESSION IN GLIOBLASTOMA". Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1585319890979393.

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Mahadevan, Geetha B. "Viral suppression of host defenses". Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0507104-110551.

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Wong, Elaine Min Yen. "The dynamics of interocular suppression". Thesis, The University of Sydney, 2008. https://hdl.handle.net/2123/28169.

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When the two eyes are presented with dissimilar images, the brain has to select one percept for awareness while suppressing the other. Interocular suppression describes the loss of Visibility of one image in favour of its competitor, and can be seen as a mechanism for understanding how, why, and Where percept selection occurs within the Visual system. This thesis addresses how and where interocular suppression takes place. By comparing the time courses of interocular With intraocular suppression, that is, Visibility loss due to conflicting images presented to only one eye, the major goal of the thesis is to show that interocular suppression occurs in two stages along the visual pathway. Four lines of experimental evidence are presented. When Viewing a monocular conditioning stimulus, the abrupt onset of a brief stimulus to the opposite eye results in a switch in perception to the new stimulus. This phenomenon is known as flash suppression. The first study (Chapter 4) investigated flash suppression under monocular and dichoptic viewing conditions to provide the intraocular and interocular time courses, respectively. This was carried out by probing Visual sensitivity to a test stimulus before, during, and after the appearance of the flash stimulus. The time course measured was the variation of threshold across time. The intraocular time course had a single elevation, a transient peak occurring Close to the time the flash stimulus was introduced. The interocular time course, on the other hand, had two elevations: the first peak was similar to that of the intraocular time course, and the second was a sustained peak starting about 100 ms later. The second study (Chapter 5) used visual masking as a technique for eliciting intraocular and interocular suppression, through monocular and dichoptic masking, respectively. In the dichoptic masking condition, one eye was presented with a masking stimulus for 100 ms. After a varying inter-stimulus interval, a brief test stimulus was presented to the other eye. The contrast threshold of the test stimulus was measured for each inter-stimulus interval. For monocular masking, both masking and test stimuli were presented to the same eye. The results showed a two-staged time course for interocular suppression, which was not apparent in intraocular suppression. Additionally, interocular suppression was more prolonged than intraocular suppression. The third study (Chapter 6) measured suppression using a different approach to the first and second studies. The experiment investigated crossorientation interactions using a stream of rapidly-changing grating orientations displayed to one eye and an independent stream to the other eye. One orientation was nominated as the target, and participants pressed a key when they saw the target. Using a reverse correlation technique, probability densities of two orientations were found. The first, 61, preceded the key-press by the reaction time, and the second, 02, preceded 61 by several hundreds of milliseconds. Analysis of the data examined the cross-orientation interactions between 6] and 92 for grating streams presented to the same eye (intraocular effect), and to different eyes (interocular effect). Despite the differences in experimentation methods between this and the masking study, the prolonged interocular suppression time course was once again apparent in the cross-orientation experiments.

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Zizz, Carol Anne 1958. "SUPPRESSION OF SPONTANEOUS OTOACOUSTIC EMISSIONS". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276339.

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Smurzynski, Jacek. "Contralateral Suppression of Otoacoustic Emissions". Digital Commons @ East Tennessee State University, 2006. https://dc.etsu.edu/etsu-works/2166.

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Renondeau, Hugues. "Evolution des propriétés tribologiques et physico-chimiques d'une graisse polyurée dans un roulement à billes de roue". Ecully, Ecole centrale de Lyon, 2004. http://bibli.ec-lyon.fr/exl-doc/hrenondeau.pdf.

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L'accroissement du poids des automobiles entraîne une quantité d'énergie à dissiper au freinage plus importante, donc une élévation de la température de fonctionnement des roulements à billes qui supportent en plus la surchage du véhicule. Parallèlement, de nouveaux types de graisses se développent sur le marché européen et américain comme les graisses à base d'épaississant polyurées. Ces nouvelles formulations sont censées répondre à un certain nombre d'exigences que réclame justement l'industrie automobile. L'étude développée ici cherche à décomposer le comportement d'une graisse dans un roulement à billes dans ses différentes étapes de fonctionnement, c'est à dire, au démarrage, au cours puis en fin de roulement. Un tribomètre bille/plan simulant le régime de lubrification élastohydrodynamique dans le roulement permet de mener l'étude expérimentale. Trois étapes sont identifées pour décrire le fonctionnement du roulement. Tout d'abord, le roulement opère en régime suralimenté. Le couplage des investigations rhéologiques et spectrométriques avec la mesure des épaisseurs de films permet d'évaluer la composition du film d'alimentation. La seconde étape est le régime de sous-alimentation qui se caractérise par des épaisseurs de films plus faibles et des mécanismes d'alimentation mettant en jeux des forces capillaires. Une approche novatrice du tribomètre bille/plan est développée et permet d'avancer plusieurs hypothèses sur les mécanismes de réalimention observés : fluide homogène ou mécanismes d'imprégnations de poreux. Il ressort de ces descriptions que l'évolution du débit de réalimentation capillaire caractérisé précédemment soit représentatif de la durée de vie du régime sous-alimenté. Finalement, la dernière étape fait intervenir la réaction des additif avec les surfaces lorsque tout le lubrifiant est consommé, on parle alors de mécanismes tribochimiques
Due to an increase of the automotive weight, the energy to be dissipated by brakes is more significant ; therefore, it leads to a rise of working temperature for the ball bearings. In the same time, new chemistries as the polyurea greases grow up on the US and EU market. These new formulations are supposed to answer to certain requirements which are precisely claimed by the automotive industry. The aim of this study is to decompose the behaviour of the grease in a ball bearing from the beginning to the end of its lifetime. The use of a ball on disc tribometer simulating the EHL regime that occurs in a bearing makes it possible. The behaviour of grease can be described by three stages. Firstly, the bearing operates in fully flooded regime. By coupling rheological and spectrometric investigations with film thickness measurement, it has been possible to determine the composition of the grease lubricating film. The second stge is the starved regime which is characterised by lower film thicknesses and a particular supply mechanism based on capillaries forces. We have developed an innovative approach based on the static used of the ball on disc device : it allows us to advance several assumptions on the supply of lubricant : either homogeneous fluid or impregnation of a porous media with lubricating phasis. Then, it gets out that the capillary flow deduced from the experiments is representative of the lifespan of this second stage. Finally, the third and last stage utilizes the reaction of additives withe surfaces when all the lubricant is consumed : on speaks of tribochemicals mechanisms

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Renondeau, Hugues Mazuyer Denis. "Evolution des propriétés tribologiques et physico-chimiques d'une graisse polyurée dans un roulement à billes de roue". Ecully : Ecole centrale de Lyon, 2004. http://bibli.ec-lyon.fr/exl-doc/hrenondeau.pdf.

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LAURENT, WILFRIED. "Determination des composantes structurales du muscle par imagerie rmn a haut champ : mise en correspondance avec l'image ultrasonore (doctorat : genie informatique)". Clermont-Ferrand 1, 2000. http://www.theses.fr/2000CLF1MM05.

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Zoppi, Ugo. "Isobar suppression in accelerator mass spectrometry /". [S.l.] : [s.n.], 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10373.

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37

Kumar, Shubham. "Suppression and control of modulation instability". Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/456080.

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Dynamical instabilities which lead to spontaneous pattern formation are present in a wide variety of nonlinear dynamical systems, both in nature as well as in technological areas. The instabilities may be saturating, leading to stationary and regular patterns, or not, leading to complex periodic structures or spatiotemporal chaos. Such pattern formation occurs universally, ranging diversely from fields such as biology and ecology to optics, hydrodynamics, condensed matter systems etc. Modulation Instability (MI), initially studied on systems such as deep-water waves, plasmas, nonlinear optics, and electromagnetics, is crucial to many current key technologies and research fields such as lasers, chemical systems, Bose-Einstein condensates of attracting atoms, high energy physics, ecology and vegetation, hydrodynamics, astrophysics etc. Despite the enormous variety of patterns in various different systems, the onset of such unstable spatiotemporal dynamics always originates through a modulation instability, when the initial, maximally-symmetric homogeneous state of the system spontaneous loses stability with respect to exponentially growing modulation modes. Therefore, the control and suppression of the MI, especially in spatially-extended systems that present a continuum (an infinite number) of unstable spatial modes, is vital for the stabilization of various such pattern-forming nonlinear systems and achieving this remains an ambitious goal. In this study, a fundamental new understanding of the MI in spatially-extended systems is developed, and a mechanism for the complete suppression of MI in such unstable systems is presented. The mechanism relies on an appropriate manipulation of the dispersion of the system, through a properly designed spatiotemporal modulation of its potential. This mechanism of MI suppression relies on a "resonant" interaction between the spatial and temporal frequencies of the modulation, which only occurs when the modulation geometry is close to the resonance. A second, much-more powerful, mechanism is also developed based on this initial understanding, in which the stabilization procedure is generalized, to form a "stabilization on demand" scheme, which achieves successful stabilization even for highly complex nonlinear systems. This method, based on the introduction of multiple "resonant" modulations of the system's potential relies on a Genetic Algorithm based optimization procedure, to suit arbitrarily complex stabilization requirements in various systems. The results bear general character, as they have been developed on the Complex Ginzburg-Landau model, which provides a universal description of MI across various systems from lasers to chemical systems, Bose-Einstein condensates, biological systems etc. Lastly, both methods are successfully applied to real-world systems, by providing a robust stabilization of MI in Broad Area Semiconductor (BAS) amplifiers and Vertical Cavity Surface Emitting semiconductor lasers. In BAS amplifiers the stabilization relays on a two-dimensional spatial modulation of the pump current, as may be provided through fishnet-like electrodes. While in the case of Vertical Cavity lasers the same may be achieved via a spatiotemporal modulation. These results have been demonstrated for realistic parameters, including large nonlinear coefficients and at high operating powers, representing a significant breakthrough in the stabilization of these widely prevalent and indispensable photonic devices.
Les inestabilitats lineals que duen a la formació espontània de patrons són presents en un ampli ventall de sistemes dinàmics no lineals, tant en sistemes naturals com o sistemes tecnològics artificials. Les inestabilitats poden saturar-se, donant lloc a patrons estacionaris regulars, o no, donant lloc a estructures periòdiques complexes o a caos espai-temporal. Aquesta formació de patrons té lloc de forma universal, abraçant camps diversos, des de la biologia i l'ecologia a l'òptica, la hidrodinàmica, o sistemes de matèria condensada, etc. La Inestabilitat de Modulació (IM), inicialment estudiada en sistemes com ara ones d'aigües profundes, plasmes, òptica no lineal, i l'electromagnetisme, és crucial per a moltes tecnologies clau actuals i camps d'investigació com ara el làser, sistemes químics, condensats de Bose-Einstein d'àtoms que s’atreuen, física d'altes energia, l'ecologia i la vegetació, la hidrodinàmica, l'astrofísica, etc. Tot i l'enorme varietat de patrons en els diversos sistemes diferents, l’aparició de la inestabilitat espai-temporal dinàmica sempre s'origina a través d'una inestabilitat de modulació, quan l'estat homogeni inicial del sistema, amb màxima simetria, perd de forma espontània l’estabilitat respecte a modes de modulació de creixement exponencial. Per tant, el control i la supressió de la IM, especialment en sistemes espacials extensos que presenten un continu de modes espacials inestables, és vital per a l'estabilització de diverses tals sistemes no lineals i l'obtenció d'això continua sent un gran repte. Aquest estudi desenvolupa un nou enfoc fonamental per a la comprensió de la IM en sistemes extensos espacials, i presenta un mecanisme per a la complerta supressió de la IM en aquests sistemes inestables. El mecanisme es basa una manipulació de la dispersió del sistema de forma adequada, mitjançant una modulació espai-temporal especialment dissenyada del seu potencial. Aquest mecanisme de supressió de MI es basa en la interacció 'ressonant' entre les freqüències espacials i temporals de la modulació, que només es produeix quan el, la geometria de modulació és a prop de la ressonància. Un segon mecanisme d’estabilització, molt més potent, es desenvolupa sobre la base d'aquesta troballa inicial, en la qual es generalitza el procediment, per donar lloc a un esquema 'estabilització a demanda', que aconsegueix una estabilització exitosa fins i tot per a sistemes no lineals altament complexes. Aquest mètode, es fonamenta en la introducció de múltiples modulacions 'ressonants' en el potencial del sistemes i es basa en un procediment d'optimització mitjançant algoritmes genètics, capaç de satisfer requisits arbitràriament complexes per l’estabilització en sistemes diversos. El resultats obtinguts tenen un caràcter general, ja que han estat desenvolupats per a l’equació de Ginzburg-Landau complexa, que proporciona una descripció universal de la IM en diferents sistemes làser, sistemes químics, condensats de Bose-Einstein, sistemes biològics, etc. Finalment, tots dos mètodes s'apliquen amb èxit per a sistemes reals, proporcionant una eina potent per a l'estabilització d’amplificadors òptics de semiconductor d’àrea ampla i làsers de semiconductor de cavitat vertical. En el cas d’amplificadors òptics l’estabilització s’aconsegueix amb la modulació en dues dimensions espacials del corrent de bombeig, per exemple proporcionat a través d'elèctrodes de reixeta. D’altra banda, pels làsers de cavitat vertical s’aconsegueix a través d'una modulació espai-temporal. Aquests resultats han estat demostrat per a paràmetres realistes incloent grans coeficients no lineals i potències de funcionament elevades. Per tot això, aquest treball representa un avenç significatiu en l'estabilització d'aquests dispositius fotònics tan comuns com indispensables.

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Wallin, Fredrik. "Combining Acoustic Echo Cancellation and Suppression". Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2011.

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The acoustic echo problem arises whenever there is acoustic coupling between a loudspeaker and a microphone, such as in a teleconference system. This problem is traditionally solved by using an acoustic echo canceler (AEC), which models the echo path with adaptive filters. Long adaptive filters are necessary for satisfactory echo cancellation, which makes AEC highly computationally complex. Recently, a low-complexity echo suppression scheme was presented, the perceptual acoustic echo suppressor (PAES). Spectral modification is used to suppress the echoes, and the complexity is reduced by incorporating perceptual theories. However, under ideal conditions AEC performs better than PAES.

This thesis considers a hybrid system, which combines AEC and PAES. AEC is used to cancel low-frequency echo components, while PAES suppresses high-frequency echo components. The hybrid system is simulated and assessed, both through subjective listening tests and objective evaluations. The hybrid scheme is shown to have virtually the same perceived quality as a full-band AEC, while having a significantly lower complexity and a higher degree of robustness.

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Araya, Tadesse. "Stereotypes: Suppression, Forgetting, and False Memory". Doctoral thesis, Uppsala University, Department of Psychology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3340.

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This thesis presents four studies investigating (1) whether incidentally primed control-related words can attenuate the impact of activated stereotypes on subsequent evaluation of a target person, (2) the impact of motivated forgetting on the recall of stereotypically congruent and incongruent information, and (3) the impact of a directed forgetting instruction on the false recall and recognition of nonpresented stereotypical information.

In three experiments, Study I showed that participants initially primed with the social category, immigrant, and subsequently primed with words that were evocative of control or self-control made less negative impression of a target displaying ambiguous behaviors than participants not exposed to such words.

Study II, using a directed-forgetting paradigm, demonstrated in two experiments that participants subliminally primed with Swedish facial photographs who later studied stereotypically incongruent words roughly recalled an equal number of items regardless of the forget or remember instructions.

Study III showed that participants primed with the social category, immigrant and then studied a list of stereotypically related and unrelated words falsely recognized more nonpresented stereotypical words when they were furnished with a forget than a remember instruction. Similarly, Study IV (Experiment 2) demonstrated that participants primed with the social category, immigrant, but not with a neutral category, falsely recalled more nonpresented stereotypical words when their cognitive capacity was depleted through a concurrent memory load task.

The thesis presents a review and a discussion of some of the theoretical underpinnings of the extant literature on stereotyping and intergroup relations and of the social implications of the present findings.

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Zhang, Ying. "Passive network synthesis for vibration suppression". Thesis, University of Bristol, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730880.

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Sui, Haichang. "Interference suppression in spread-spectrum networks". Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3258023.

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Thesis (Ph. D.)--University of California, San Diego, 2007.
Title from first page of PDF file (viewed May 25, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 154-171).

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Mucke, Sven. "Visual suppression during dynamic ocular accommodation". Thesis, Glasgow Caledonian University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.547426.

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Nichols, Emma. "Chemically enhanced water mist fire suppression". Thesis, Ulster University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528379.

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Since the phasing out of halons, water mist systems have gained attention as a possible alternative form of fire suppression. These ultrafine sprays have both advantages and disadvantages compared to conventional water sprinklers. It has been suggested that one way to improve their performance would be to produce the mist from an aqueous solution of a chemical fire suppressant. Two small-scale experiments were devised to quantify and compare the suppression efficiency of the mists of chemical solutions. Twelve potential chemical suppressants were selected from a review of the literature and delivered into the fires as mists of their solutions at 3-10% m/v concentration; their effect on the time taken to extinguish the flame was recorded. In addition, 90 full scale fire tests were conducted to identify how suppression might best be improved with chemical additives, and a mathematical model was constructed to estimate optimum droplet parameters for various conditions. In the small scale experiments, solutions of KHCO3, other compounds of alkali metals, and seawater showed excellent improvement to the extinction time. On the large scale, a body of research on the comparatively under-studied wood crib fires was compiled, and it was concluded there was scope for using chemically enhanced water mist to provide effective room coverage with fewer nozzles. This research was original in that it studied a range of chemical suppressants which had largely not been tested in the form of water mist additives; it had an emphasis on the application of the results on real fires, quantifying suppression efficiency by the time taken to suppress a flame; the large scale experiments centred around class A fires; it attempted to provide a wide-ranging and systematic approach to the question of chemically enhanced water mist systems by looking at small scale screening tests, full scale fire tests, and modelling.

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Ferron, Judy-Fay. "Étude in vivo du "burst-suppression"". Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26218/26218.pdf.

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Cette étude résume certains concepts liés à l’anesthésie générale, détaille les mécanismes d’action de l’isoflurane, un anesthésiant volatil, et aborde le phénomène du burst-suppression. Elle vise principalement la compréhension de l’impact de l’isoflurane, à des doses amenant le burst-suppression, sur l’inhibition dans le réseau thalamo-cortical. Nous effectuons des enregistrements intracellulaires de neurones corticaux in vivo et de potentiels de champs locaux à différentes doses d’anesthésiants chez le chat. Conjointement à ces enregistrements, nous appliquons des drogues en iontophorèse en péri-synaptique des neurones enregistrés et nous stimulons les noyaux thalamiques projetant dans les aires corticales enregistrées. Nous suggérons que l’isoflurane amène une diminution de l’inhibition corticale, via une plus grande recapture du glutamate par les glies, ce qui diminue l’activation des interneurones corticaux.
This study summarizes some concepts about general anesthesia, details the mechanisms of action of the volatile anesthetic isoflurane and describes the phenomenon of burst-suppression. It aims at understanding the impact of isoflurane, under doses sufficient to induce burst-suppression, on inhibition in the thalamo-cortical network. We performed intracellular recordings of cortical neurons in vivo and local field potentials under different doses of anesthesia in cats. Additionally, we applied drugs in iontophoresis in the perisynaptic space of the recorded neurons and we stimulated thalamic nuclei projecting to the areas where recordings were performed. We suggest that isoflurane diminishes the cortical inhibition, by an increase of the glutamate uptake by glial cells leading to a diminished activation of cortical interneurons.
Inscrite au Tableau d'honneur de la Faculté des études supérieures

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Bisschop, Roeland, e Zijlstra Fêdde. "Redesigning fire suppression system for safety". Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-36011.

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This degree project is divided into two subprojects. Both of the projects are executed for Fogmaker, a company that specialises in designing and installing fire suppression systems in engine compartments. These projects are executed according to product development methods. The first subproject described in this report is about designing a handle for the transportation of a 35kg weighing fire extinguisher. The handle functions as a safety seal and as a grip that makes it easier and safer to lift the fire extinguisher. A casted zinc T-handle is the best solution based on cost and AHP (Analytic Hierarchy Process) analysis. An FMECA (Failure Mode Effect and Criticality Analysis) and a FEM (Finite Element Method) study have been performed to verify the design. A zinc prototype of the safety handle has been manufactured and is ready for testing. It is expected that 10.000 handles will be produced every year once this prototype is approved by Fogmaker. The second subproject concerns a connection hub placed on a pressurized bottle. In order to make the fire suppression system more reliable this component needs to be redesigned. An external company with the required expertise in hydraulic systems will develop the connection hub in cooperation with Fogmaker, based on the conceptual designs described in this report. An FMECA of the new connection hub concept proves this redesign increases the safety of the system. The overlying subject of both of these projects is the safety of the fire suppression system. Thanks to the accomplishment of both project, the system has become safer and more reliable.

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Gee, Ian. "Tailoring immune suppression following liver transplantation". Thesis, University of Leicester, 2005. http://hdl.handle.net/2381/27585.

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Liver transplantation was first performed in 1963 (1) as an experimental treatment for end stage liver disease. Three patients were transplanted, all of whom died within 3 weeks. Since then it has become an established therapy resulting in improved quality of life (2), with 675 transplants from cadaveric donors taking place in the UK in 2001 and 706 in 2002 (3). This level of activity compares with 10 years ago when 502 liver transplants were performed in 1992. Figures released for survival up to the year 2000 show that early (1 year) survival has improved to 88% for patients transplanted from 1998 – 1999, with 3 year survival for the period 1996 – 1997 being 73% and 5 year survival for the period 1994 – 1995 being 64% (3). This improvement is probably due to a combination of factors such as improved surgical and anaesthetic technique, changes in medical management after transplantation, the improved recognition of other harmful factors like hypertension, choice of immune suppression and better prediction of patients in whom liver transplantation is not likely to be appropriate such as those with cholangiocarcinoma or multiple large hepatocellular carcinomas. [Taken from Introduction]

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Bridgett, Stephen John. "Detail suppression of stress analysis models". Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387980.

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Zhu, Jianfeng. "Vibration suppression by using magnetic damping". Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440844.

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Lee, Evan J. (Evan Joseph). "Airfoil Vortex Induced Vibration suppression devices". Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39874.

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Thesis (S.M. in Naval Architecture and Marine Engineering; and, S.M. in Ocean Systems Management)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2007.
"May 2007."
Includes bibliographical references (p. 51).
Vortex Induced Vibrations (VIV) is a major concern of the offshore oil industry. This problem leads to fatigue failure in the marine risers and causes costly replacement of the risers. Appendages such as helical strakes have proven that VIV can be eliminated but at the cost of increased drag. Increased drag reduces the time that the riser can operate. This thesis looks at adding airfoils to cylinders to both eliminate VIV as well as reducing drag. Two sets of tests were performed at the MIT Towing Tank to determine the effectiveness of these airfoils. The first tests utilized a flexible to model a riser. The second set of tests used a rigid cylinder to better understand the dynamics of the system. The airfoils were able to achieve both goals when the airfoils are aligned with the flow. Future work needs to be completed to study the airfoils when they are not aligned with the flow.
by Evan J. Lee.
S.M.in Naval Architecture and Marine Engineering; and, S.M.in Ocean Systems Management

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Терлецька, Ірина Миколаївна, Ирина Николаевна Терлецкая, Iryna Mykolaivna Terletska, V. Gelykh e I. Vashchenko. "The ambulatory patients' acute pain suppression". Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/15949.

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Teses / dissertações sobre o tema "Suppression de la graisse"

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