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Roy, Mahendra Nath. "Studies on the ion-solvent interactions of some tetraalkylammonium and common ions in non-aqueous and mixed solvents." Thesis, University of North Bengal, 1993. http://hdl.handle.net/123456789/740.
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Dey, Rabindra. "Studies on the ion-solvent interactions of tetraalkylammonium and common ions in tetrahydrofuran and its binary mixtures." Thesis, University of North Bengal, 2005. http://hdl.handle.net/123456789/773.
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Davey, Cara-Lee. "Development of an Ion Chromatography Method for the Analysis of Nitric Acid Oxidation Reactions of Common Sugars." The University of Waikato, 2008. http://hdl.handle.net/10289/2407.
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The large scale nitric acid oxidation of common sugars into their corresponding aldaric acids is being investigated as an important source of potentially useful components for industrial applications such as polymers. This thesis details the development of an Ion Chromatography (IC) method for the analysis of these oxidation mixtures and related samples from the work-up and purification processes. The method was developed for use with a Dionex ICS2000 IC system equipped with an AS11-HC column and utilising suppressed conductivity detection. IC proved to be a useful, versatile and straightforward method of studying the reactions and their products. The detected ions include but are not restricted to the anionic salt forms of: D-Glucaric acid, Xylaric acid, Mannaric acid, D-gluconic acid and both keto forms of the same, D-xylonic acid, D-mannonic acid, glycolic acid, oxalic acid, tartaric acid and tartronic acid. Nitrate from the nitric acid used in the oxidation is often observed. The results compare favorably to GC-MS and HPLC analysis of similar samples. An overview of the theory and operation of the instrument along with the method development and results from application to the oxidation mixtures and related samples are presented. As part of the investigation into the range of utility of IC for studying these reactions, a study was made of the retention behaviour of a large number of simple and low molecular weight (LMW) carboxylic acids eluted by the ion chromatography system in use. The results of this study are included with an explanation of the major factors affecting anion retention on the column
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Das, Bijan. "Physico - chemical investigations on the ion-solvent interactions of some Tetraalkylammonium and common ions in non-aqueous and mixed binary aqueous solvent systems." Thesis, University of North Bengal, 1992. http://hdl.handle.net/123456789/719.
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Rudolph, Wolfram W., and Gert Irmer. "Hydration and ion pair formation in common aqueous La(III) salt solutions: a Raman scattering and DFT study." Royal Society of Chemistry, 2015. https://tud.qucosa.de/id/qucosa%3A36118.
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Raman spectra of aqueous lanthanum perchlorate, triflate (trifluorosulfonate), chloride and nitrate solutions were measured over a broad concentration (0.121–3.050 mol Lˉ¹) range at room temperature (23 °C). A very weak mode at 343 cmˉ¹ with a full width at half height at 49 cmˉ¹ in the isotropic spectrum suggests that the nona-aqua La(III) ion is thermodynamically stable in dilute perchlorate solutions (∼0.2 mol Lˉ¹) while in concentrated perchlorate solutions outer-sphere ion pairs and contact ion pairs are formed. The La³⁺ nona-hydrate was also detected in a 1.2 mol Lˉ¹ La(CF₃SO₃)₃(aq). In lanthanum chloride solutions chloro-complex formation was detected over the measured concentration range from 0.5–3.050 mol Lˉ¹. The chloro-complexes in LaCl₃(aq) are fairly weak and disappear with dilution. At a concentration <0.1 mol Lˉ¹ almost all complexes disappeared. In LaCl₃ solutions, with additional HCl, a series of chloro-complexes of the type [La(OH₂)₉₋nCln]⁺³⁻ⁿ (n = 1–3) were formed. The La(NO₃)₃(aq) spectra were compared with a spectrum of a 0.409 mol Lˉ¹ NaNO₃(aq) and it was concluded that in La(NO₃)₃(aq) over the concentration range from 0.121–1.844 mol Lˉ¹, nitrato-complexes, [La(OH₂)₉₋n-(NO₃)n]⁺³⁻ⁿ (n = 1, 2) were formed. These nitrato-complexes are quite weak and disappear with dilution <0.01 mol Lˉ¹. DFT geometry optimizations and frequency calculations are reported for a lanthanumnona-hydrate with a polarizable dielectric continuum in order to take the solvent into account. The bond distances and angles for the cluster geometry of [La(OH₂)₉]³⁺ with the polarizable dielectric continuum are in good agreement with data from recent structural experimental measurements and high quality simulations. The DFT frequency of the La–O stretching mode at 328.2 cmˉ¹, is only slightly smaller than the experimental one.
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Kirmess, Kristopher Michael. "Investigation of Primary Ion Formation Mechanisms in UV-MALDI-MS Using Excited State Dynamics of Common MALDI Matrices." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/dissertations/1110.
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The motivation of this dissertation is to provide insight towards primary ionization mechanisms within MALDI mass spectrometry. Albeit MALDI-MS is an extensively used analytical technique, the mechanism in which primary ions are created is still under scrutiny. Two current models of primary ionization exist which claim to elucidate the ion formation mechanisms within MALDI. In this work, excited state dynamics of MALDI matrices are shown to play an important role in the ionization mechanism. Upon inspection of the thermodynamic properties of commonly used MALDI matrices, no correlation was observed when plotted against their respective analyte ion yields. However, the excited state singlet lifetimes of these matrices seem to correlate well with their respective analyte ion yields. In the broadest sense, this correlation further supports the fact that photophysical properties of the matrix should be included in current UV-MALDI models. Investigation of a claim which stated singlet energy pooling reactions were absent in the MALDI matrix 2,4,6-trihydroxyacetophenone (THAP) resulted in the discovery of a new energy pooling mechanisms. Characteristic of aromatic ketones such as THAP, intersystem crossing is an efficient process in solution, which gives way to fluorescence in the solid state. Triplet pooling mechanisms from two neighboring THAP molecules are proposed and appear to be dependent on the preparation solvent used. These triplet pooling reactions are thought to play an important role in the primary ion formation mechanism within MALDI. To further investigate the theory of triplet species playing a vital role in MALDI ionization, the internal heavy-atom effect was employed to determine the effect of the triplet species. MALDI mass spectra and excited state decays of these heavy-atom substituted matrices were collected to demonstrate the relationship between triplet species and analyte ionization efficiency. Gas-phase thermodynamics and absorption at 337 nm were also examined to determine if these properties affected the analyte ion signal observed in the MALDI mass spectrum. Using the information collected from the previous study, an advanced MALDI matrix is synthesized. Addition of covalently bound iodine to the gold standard matrix, α-cyano-hydroxycinnamic acid, should drastically improve the performance of the non-substituted matrix due to the increase in triplet species present for pooling reactions. Sample preparation methods in MALDI are examined as are the effects of crystal morphology on the overall signal observed in the mass spectrum. Exciton hopping and pooling rates are highly dependent on intermolecular interactions, so it is expected that crystal packing will affect MALDI. As noted for THAP, preparation solvent plays a significant role in not only crystal morphology, but also the excited state dynamics for all matrices studied.
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Albury, Cassie Louise. "Using whole exome sequencing and genetic association studies to investigate common and complex migraine." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/122954/1/Cassie_Albury_Thesis.pdf.
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This dissertation focused on expanding the knowledge and understanding of common and complex migraine genetics. The central objectives of this research was to 1) identify new migraine causative genes using modern sequencing techniques and; 2) investigate potential genetic associations between common and complex migraine. This study has successfully identified 1) a susceptibility association between a potential familial hemiplegic migraine (FHM) gene and common migraine and; 2) implicated 4 new genes as potentially FHM causative. As a result of this study we foresee the development of a more comprehensive genetic test with improved diagnostic success rates.
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Kaliszczak, Magdalena. "Polarisation chimique de l'interface liquide-liquide vers une cocristallisation contrôlée." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0332.
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La formation contrôlée de cocristaux est un objectif important dans le developpement de médicaments. Ce travail a utilisé l'électrochimie à l'interface entre deux liquides non miscibles (ITIES) pour contrôler la formation de cocristaux. Dans la première partie, le comportement électrochimique de la caféine a été étudié au moyen de la voltampérométrie cyclique (CV) et de la voltampérométrie à courant alternatif (ACV). La caféine est un cation hydrophile donc, elle a été transférée à un potentiel hautement positif. Le transfert de la caféine (CaffH+) a été vérifié à différents pH et le pH 2 a été choisi comme étant le plus optimal pour la formation de cocristaux. L'expérience de contrôle a prouvé que le 1-hydroxy-2-naphtoïque (1H2N) ne transfére pas à l'ITIES. L'ACV a fourni des informations sur l'influence de la composition de la phase aqueuse et organique. Les valeurs ont changé lorsque CaffH+ seul, 1H2N seul et 1H2N et CaffH+ étaient présents dans la phase aqueuse. Ces résultats suggèrent que ces deux molécules sont actives au niveau interfacial. Dans la deuxième partie, la cocristallisation de Caff et 1H2N a été étudiée à l'ITIES sous polarisation chimique. L'interface a été polarisée par l'ajout d'anions hydrophobes à la phase organique. De cette façon, une cocristallisation sélective a été obtenue, comme vérifié par la diffraction des rayons X et la spectroscopie Raman. Des potentiels interfaciaux positifs ont favorisé la formation d'une forme polymorphe de cocristal de Caff : 1H2N et un potentiel négatif a inhibé la cocristallisation à l'interface liquide-liquide. Cette approche du contrôle électrochimique de la cocristallisation ouvre de nouvelles possibilités pour le développement de médicaments. Dans la troisième partie, la mesure simultanée des variations de potentiel (∆E) et de courant (I) aux ITIES, qui ont été polarisées en utilisant des cations tétraalkylammonium comme ion commun a été rapportée. Divers rapports de concentration de tétraméthyl-, tétraéthyl- et tétrapropylammonium ont été dissous dans les deux phases. Ces systèmes biphasiques ont ensuite été utilisés pour vérifier que la différence de potentiel interfacial mesurée correspondait aux calculs théoriques. Ce dispositif expérimental a ensuite été utilisé pour étudier le processus de cocristallisation interfaciale de CaffH+ hydrophile et cationique avec 1H2N lipophile. La présence de caféine dans la phase aqueuse a conduit à des valeurs de courant plus élevées, causées par le transfert de charge interfacial. De telles variations de courant ont été observées aussi bien en l'absence qu'en présence de 1H2N dans la phase organique. L'analyse du bruit du courant électrochimique a montré une nette différence entre les cellules dans lesquelles les cocristaux sont formés et celles dans lesquelles la cocristallisation est entravée, soit par un potentiel négatif, soit par un changement de pH. La méthode ECN est un outil puissant pour suivre les changements qui se produisent aux ITIES dans les expériences sur les ions communs par la mesure simultanée du potentiel et du courant. Dans la dernière partie, des cocristaux ont été formés sur les ITIES selon les conditions choisies par la méthode des plans d'expériences (DoE). Différents facteurs ont été testés : électrolytes en phase aqueuse, divers solvants et sels appliquant un potentiel positif. L'analyse XRD a montré les conditions permettant d'obtenir une phase I et une phase II presque pures. L'étude des ∆E et I simultanés et de la tension interfaciale a prouvé que le potentiel appliqué influence la cinétique du processus de cocristallisation. La méthode DoE a indiqué que le sel organique est le facteur ayant un impact actif sur la cocristallisation aux ITIES<br>Controlled formation of cocrystals is an important objective in drug development. This work used the electrochemistry at interface between two immiscible liquids (ITIES) to control the formation of cocrystals. In the first part, the electrochemical behaviour of caffeine was investigated by the means of cyclic voltammetry (CV) and alternating current voltammetry (ACV). The caffeine is the hydrophilic cation thus, it transferred at highly positive potential. Transfer of caffeine (Caff) was verified at various pH and the pH 2 was chosen to be the most optimal for the cocrystals formation. The control experiment proved that 1-hydroxy-2-naphthoic (1H2N) did not transfer at ITIES. ACV provided the information about the influence of the aqueous and organic phase composition. Values have changed when CaffH+ alone, 1H2N alone and both 1H2N and CaffH+ were present in the aqueous phase. These suggest that these two molecules are interfacially active. In the third part the simultaneous measurement of potential (∆E) and current (I) variations at the ITIES, which were polarised using tetraalkylammonium cations as a common ion was reported. Various concentration ratios of tetramethyl-, tetraethyl-, and tetrapropylammonium were dissolved in both phases. Such biphasic systems were then used to verify that the interfacial potential difference measured fit the theoretical calculations. This experimental set-up was next used to probe the interfacial cocrystallisation process of hydrophilic and cationic CaffH+ with lipophilic 1H2N. The presence of caffeine in the aqueous phase led to higher current values, caused by interfacial charge transfer. Analysis of the electrochemical current noise showed a clear difference between cells in which cocrystals are formed and those in which cocrystallisation is hindered, either by a negative potential or by a change in pH. The EN method is a powerful tool to follow the changes occurring at ITIES in common ion experiments by simultaneous measurement of potential and current. In the last part, cocrystals were formed on the ITIES according to the conditions chosen by the design of experiments (DoE) method. Various factors were tested: electrolytes in the aqueous phase, various solvents and salts applying positive potential. The XRD analysis showed the conditions to obtain almost pure Phase I and almost pure phase II. Study of simultaneous ∆E and I and the interfacial tension proved that the applied potential influences the kinetics of the cocrystallization process. DoE method indicated organic salt as the factor having an active impact on cocrystallization at ITIES
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Kormoll, Thomas. "A Compton Camera for In-vivo Dosimetry in Ion-beam Radiotherapy." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-107368.
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In dieser Arbeit wird die Bildgebung durch eine Compton-Kamera zur Überwachung der Partikelstrahlentherapie erstmals an der Technischen Universität Dresden untersucht. Die inhärenten Beschränkungen der Methode wurden durch Berechnungen und Monte Carlo Simulationen studiert. Im Zuge dieser Untersuchungen erschien der Raumtemperatur-Halbleiter Cadmium Zink Tellurid als ein vielversprechendes Detektor-Material. Zur weiteren Untersuchung wurde eine einfache Compton-Kamera konstruiert bestehend aus einem Cadmium Zink Tellurid Detektor und einem ortsempfndlichen Szintillationsdetektor. Das System hat gezeigt, dass eine akkurate Bildgebung mit radioaktiven Punktquellen unter Laborbedingungen möglich ist. Weitere praktische Beschränkungen der Compton-Bildgebung unter Strahlbedingungen konnten durch Experimente an einem Protonen-Strahl hergeleitet werden. Durch die experimentellen Erfahrungen mit der in dieser Arbeit entwickelten Compton-Kamera konnten wertvolle Informationen gesammelt werden, die erlauben, die Bildrekonstruktion zu evaluieren und dazu beitragen, die weitere Forschung hin zu einer klinisch anwendbaren Compton-Kamera zu leiten<br>This work presents the first efforts at the Dresden University of Technology to study the feasibility of Compton imaging as a modality to monitor ion beam radiation therapy. The inherent limitations of the method have been studied by means of calculation and Monte Carlo simulation. As a result, the room-temperature semiconductor cadmium zinc telluride appeared as a promising detector material for a clinical device. For more detailed investigation, a simple Compton camera has been constructed comprising a cadmium zinc telluride detector and a position sensitive scintillation detector. This system has proven that accurate imaging of radioactive point sources in the laboratory is feasible. More practical restrictions of Compton imaging in beam conditions have been derived through experiments at a proton facility. Through the experimental work with the Compton camera developed in this work, valuable information was gathered which allowed to test the image reconstruction and to direct the further research towards a clinical Compton camera system
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Cumeras, Olmeda Raquel. "Micro Ion Mobility Spectrometry for Gas-phase Detection." Doctoral thesis, Universitat Autònoma de Barcelona, 2013. http://hdl.handle.net/10803/131286.
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En un món ideal, podríem ser capaços de detectar ràpidament i classificar qualsevol tipus de substància química i biològica que es trobés en baixes concentracions, utilitzant instruments petits i de fàcil ús. És en aquest escenari on va aparèixer l'espectrometria de mobilitat iònica (IMS). Es tracta d'una tècnica de mesura i anàlisi, on els analits ionitzats es separen per diferències de mobilitat sota la influència d’un camp elèctric en un flux de gas neutre o d'aire a pressió i temperatura ambient. Els avantatges de l'IMS inclouen instrumentació compacte i portàtil, un temps de separació curt (escala de mili-segons), i uns límits de detecció baixos, i permeten una àmplia gamma d'aplicacions. En aquest sentit, un esforç intens de recerca s'ha enfocat cap a la miniaturització dels dispositius d'IMS disponibles vers als micro- espectròmetres de mobilitat iònica de forma d’ona asimètrica i d’alt camp (FAIMS).
En aquesta tesi es presenten els primers desenvolupaments i contribucions tecnològiques als FAIMS en el IMB-CNM (CSIC). En particular, aquest treball està dedicat a la simulació, disseny, i fabricació d'un micro FAIMS planar (p-FAIMS) per a aplicacions de seguretat. El treball s'organitza en cinc capítols dividits en dues seccions.
La primera secció consta de tres capítols. El primer capítol és introductori i en el segon capítol s'introdueix al lector en l'actual estat de la tècnica de l'espectrometria de mobilitat iònica en general i en particular per als micro- espectròmetres de mobilitat iònica de forma d’ona asimètrica i d’alt camp. El tercer capítol descriu el modelatge d'un tipus de FAIMS planar per a diferents camps elèctrics i condicions de flux.
La segona part consta de dos capítols. El quart capítol presenta un resum dels diferents dissenys i materials considerats per a la implementació del p-FAIMS: estructures Vidre-Si-Vidre i PCB-PMMA-PCB, les tasques tecnològiques fetes per cada un i les estratègies de solució que hi han conduit. La fotoionització UV ha estat l'escollida com a mètode de ionització en tots els casos per raons de seguretat. També es presenta la caracterització amb toluè del nou prototip de p-FAIMS de baix cost fabricat a l'IMB-CNM. El cinquè capítol es presenta un resum de l'estudi de la viabilitat del monitoratge d'un fàrmac analgèsic (remifentanil) en l’alè de pacients sota anestèsia. Un espectròmetre de mobilitat iònica comercial s'utilitza per a aquesta aplicació mèdica en col·laboració amb el KIST-Europe i la Chirurgische Universitätsklinik d'Homburg (Alemanya).<br>In an ideal world, we might be able to rapidly detect and classify any type of chemical and biological that is found in low concentrations, using instruments of small size and easy implementation. Is in that scenario where the Ion mobility spectrometry (IMS) appeared. It is a technique of measurement and analysis, where ionized analytes are separated by mobility differences under electric field in a flow of neutral gas or air at ambient pressure and temperature. The advantages of IMS include compactness and portability of instrumentation, short separation time (milliseconds scale), and low detection limits, and allow a wide range of applications. In this sense, an intense research effort has been focused towards miniaturization from the available IMS’s devices to the micro high-Field Asymmetric waveform Ion Mobility Spectrometers (FAIMS).
This thesis presents the first developments and technological contributions to the FAIMS at IMB-CNM (CSIC). Particularly, this work is dedicated to the simulation, design, and fabrication of a micro planar FAIMS (p-FAIMS) for security applications. The work is organized in five chapters divided in two sections.
The first section consists of three chapters. Chapter one is introductory, and on Chapter two introduces the lector to the actual state-of-the-art of the Ion Mobility Spectrometry in general and in particular for the micro high-Field Asymmetric waveform Ion Mobility Spectrometry. Chapter three described the modeling of a planar type of FAIMS for different electric fields and flow conditions.
The second section consists of two chapters. Chapter four provides a summary of the different designs and materials considered for the p-FAIMS implementation: Glass-Si-Glass and PCB-PMMA-PCB structures; the technological tasks done for each one and the solving strategies that have leaded to it. UV photoionization has been the chosen as ionization method for safety reasons in all cases. It also presents the characterization with toluene of the new low-cost p-FAIMS prototype fabricated in the IMB-CNM. Chapter five provides a summary of the feasibility study of an online-monitoring of an analgesic drug (remifentanil) in patients breath under anesthesia. A commercial Ion Mobility Spectrometer is used for this medical application in collaboration with the KIST-Europe and the Chirurgische Universitätsklinik from Homburg (Germany).
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Öing, Heinz. "Entwicklung eines neuen dieselmotorischen Injektorkonzeptes für zukünftige Emissionsgrenzwerte." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960295925.
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Busch, Roger. "Untersuchung von Kavitationsphänomenen in Dieseleinspritzdüsen." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962066672.
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Ofner, Bernd. "Dieselmotorische Kraftstoffzerstäubung und Gemischbildung mit Common-Rail-Einspritzsystemen." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963990381.
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Eisen, Sven-Michael. "Visualisierung der dieselmotorischen Verbrennung in einer schnellen Kompressionsmaschine." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969361564.
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Hedkvist, Adam, and Henrik Ahrman. "Simulation of helium flow through ion guide with COMSOL multiphysics." Thesis, Uppsala universitet, Tillämpad kärnfysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-296242.
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The program COMSOL Multiphysics was used to simulate a flow of helium gas transporting ionized fission products out of an ion guide. Two important parameters to study from the simulation was the evacuation time and velocity of the ions. The mean evacuation time was shown to be 0.1173s, and the velocity of a single particle peaked at 2500m/s, 1000-1500m/s being more common.
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Freixas, Jérémy. "Microbatteries 3D zinc-air ou comment repousser les limites des technologies lithium-ion." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4014/document.
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Ces travaux de thèse se sont focalisés sur la miniaturisation d'une batterie zinc-air, dispositif qui présente l'avantage d'avoir une densité d'énergie massique et volumique théorique supérieure à celle de la technologie lithium-ion, majoritairement étudiée dans la littérature. Le micro-usinage d'un substrat de silicium permet de définir le squelette d'électrodes à forte surface spécifique : le gain géométrique des structures 3D se répercute alors sur les performances de stockage des charges des électrodes de la microbatterie. Différentes géométries de microstructures 3D ont été étudiées : à titre d'exemple, des tubes de taille micrométrique (4,2μm de diamètre), profonds de 109μm (rapport d'aspect de 60: 1) permettent d'obtenir un rapport entre la surface spécifique et l'empreinte surfacique de 70. Ce squelette est ensuite recouvert de matériaux actifs à l'aide de procédés de dépôts conformes. Cette démarche a permis la mise au point d'une électrode métallique 3D en zinc (couche mince de 300nm) présentant une capacité spécifique de 1mAh.cm-2 en milieu aqueux (hydroxyde de potassium 0,7M). La tension de la cellule est de 1,2V. Pour la première fois, une électrode à air miniaturisée a été fabriquée, basée sur la création d'un réseau de micro-canaux poreux sur la face avant du substrat silicium, et la gravure d'une cavité sur la face arrière. Dès lors que le silicium est usiné, un dépôt de platine permet d'assurer le caractère conducteur de l'électrode tandis qu'un dépôt de dioxyde de manganèse lui apporte des propriétés catalytiques. Ce concept original d'électrode à air 30 présente un fonctionnement similaire à une électrode commerciale, malgré une taille bien plus réduite<br>The studies presented in the frame of this thesis are focused on zinc-air battery miniaturization, an electrochemical energy storage system that shows a higher volumetric and gravimetric energy density than the lithium-ion technology, mostly investigated in literature. The micromachining of a silicon substrate allows designing a high specific surface scaffold: 3D geometrical gain enhances the properties of charge storage for the electrodes of the microbattery. 3D microstructures exhibiting various geometrical designs have been studied: for instance, silicon micro-tubes (4,2μm outer diameter) 109 μm-depth (60:1 aspect ratio) provide a specific surface to the footprint ratio close to 70. Then, this scaffold is coated by the active materials using conformal depositions methods. This process leads to a 3D zinc metallic anode (300nm-thick) exhibiting a surface capacity of 1mAh.cm-2 in aqueous electrolyte (potassium hydroxide 0,7M). Cell voltage is 1,2V. For the first time in literature, a miniaturized air electrode has been manufactured, based on a porous microchannel network on the front side of silicon substrate, and the etching of a cavity on the back side. Once silicon wafer is micromachined, a platinum conformal thin film provides the conductive properties to the electrode while a manganese dioxide layer enhances the catalytic activity. This original concept of 3D air electrode presents a behavior similarly to a commercial one, but with a significant reduced size
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Potgieter, JH, SS Potgieter, CA Strydom, and O. Gheevarhese. "The influence of various common ions on the slaking of some South African limes." Water SA, 2003. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000887.
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The rate of transformation from CaO to Ca(OH)2 during the slaking process is influenced by a number of factors. In this
investigation the effects of common ions normally encountered in the slaking water were investigated. It was found that chloride
and nitrate ions enhanced the slaking rate, while carbonate, sulphate and phosphate ions retarded the hydration of various limes
used in the investigation. The increases and decreases in the degree of hydration correlate with the solubilities of the anions forming
more soluble compounds than Ca(OH)2, as well as the solubility constants of the anions that formed less soluble compounds than
the hydrated lime. The geological origin of the lime also influenced the slaking of the limes.
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Naumann, Tino. "Wissensbasierte Optimierungsstrategien für elektronische Steuergeräte an Common-Rail-Dieselmotoren." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965199878.
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Nothnagel, Michael. "The definition of multilocus haplotype blocks and common diseases." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973611448.
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Koch, Oliver. "Common genetic variants of the IFN-γ and IFNGR1 regions : disease associations and functional properties". Thesis, University of Oxford, 2003. http://ora.ox.ac.uk/objects/uuid:30fc15ae-13e5-4150-8093-2582334e75c0.
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There is growing evidence that susceptibility to many inflammatory and infectious diseases may be influenced by our genetic make up. Genetic variants in important immune genes may partially explain variation in susceptibility to common diseases. Interferon-γ (IFNγ) is one of the central mediators of the innate and adaptive immunity and has been implicated in a wide range of infectious and inflammatory disease processes. Severe disruptive mutations in coding regions of the IFN-γ receptor 1 gene (IFNGR1) have been found to be associated with fatal but very rare mycobacterial infections. This study looked at common polymorphisms in potentially regulatory non-coding regions of the IFNγ gene and the IFNGR1 gene and investigated their association with susceptibility to severe malaria, a disease for which there have been indications of a genetic component to susceptibility. Malaria is one of the major causes of childhood deaths in Africa. IFNγ and its receptor have been shown to be critically involved in the host response to the malaria parasites. The promoter regions of IFNGR1 and its neighbouring genes, located on chromosome 6q23, and IFNγ and its neighbours, on chromosome 12ql4, were screened for polymorphisms. Haplotypes and linkage disequilibrium maps were constructed, signatures of natural selection were investigated, haplotype tagging SNPs were dentified, and association with disease was analysed. One of these preliminary results was a putative association between the IFNGRl-470ddel allele and susceptibility to severe malaria in the Mandinka ethnic group. This allele was in strong linkage disequilibrium (LD) with markers which are a considerable distance away which might represent a signature of natural selection. To assess the potential functional significance of the IFNGR1-47Q polymorphism, its effects on DNA-protein interactions and gene expression was investigated further in various cell lines. Evidence of tissue-specific nuclear protein binding to this site which seems to be involved in transcriptional regulation was observed.
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Lindqvist, Daniel. "Simulation of Intermittent Current Interruption measurements on NMC-based lithium-ion batteries." Thesis, Uppsala universitet, Strukturkemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-325298.
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The objective of this report was to implement battery cycling and an intermittent current interruption (ICI) method for determining battery resistance into a simple lithium-ion battery model in the finite element methods (FEM) program COMSOL Multiphysics, andevaluate how accurately the model reflects the behaviour of voltage and internal resistance with respect to experimental results. The ICI technique consists of repeating the steps of first having a longer charging period and then having a short current interruption, where the internal resistance is calculated from the voltage drop that occurs when the current is turned off. The model was evaluated against measurements, made with the same technique (ICI), on assembled NMC-graphite batteries. Codes written in the statistical programming language “R” were used to process the data from both COMSOL and the experiments. Both the batteries and the model were constructed with a reference electrode, to enable measurement of each electrode by itself. The results as documented in this report show that it is possible to simulate the measurement technique in COMSOL, but that both the resistance and voltage profiles differed quite a lot from the behaviour of the tested batteries. The resistance of the positive electrode did however give good results and it was possible to improve the model by changing some parameters. The magnitude of the resistance, which was already quite close, could be improved by changing the porosity and particle size, and the voltage profiles were improved when using voltage-data achieved from the real measurements.
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Falconi, Andrea. "Modélisation électrochimique du comportement d’une cellule Li-ion pour application au véhicule électrique." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI043/document.
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Le développement futur des véhicules électriques est lié à l’amélioration des performances des batteries qu’ils contiennent. Parallèlement aux recherches sur les nouveaux matériaux ayant des performances supérieures en termes d'énergie, de puissance, de durabilité et de coût, il est nécessaire développer des outils de modélisation pour : (i) simuler l'intégration de la batterie dans la chaine de traction et (ii) pour le système de gestion de la batterie, afin d'améliorer la sécurité et la durabilité. Soit de façon directe (par exemple, la prévention de surcharge ou de l’emballement thermique) soit de façon indirecte (par exemple, les indicateurs de l’état de charge). Les modèles de batterie pourraient aussi être utilisés pour comprendre les phénomènes physiques et les réactions chimiques afin d'améliorer la conception des batteries en fonction des besoins de l’utilisateur et de réduire la durée des phases de test. Dans ce manuscrit, un des modèles les plus communs décrivant les électrodes poreuses des batteries au lithium-ion est revisité. De nombreuses variantes dans la littérature s’inspirent directement du travail mené par le professeur J. Newman et son équipe de chercheurs à l’UC Berkeley. Pourtant relativement peu d’études analysent en détail les capacités prédictives de ce modèle. Dans ce travail, pour étudier ce modèle, toutes les grandeurs physiques sont définies sous une forme adimensionnelle, comme on l'utilise couramment dans la mécanique des fluides : les paramètres qui agissent de manière identique ou opposée sont regroupés et le nombre total de paramètres du modèle est considérablement réduit. Cette étude contient une description critique de la littérature incluant le référencement des paramètres du modèle développé par le groupe de Newman et les techniques utilisées pour les mesurer, ainsi que l’écriture du modèle dans un format adimensionnel pour réduire le nombre de paramètres. Une partie expérimentale décrit les modifications de protocoles mis en œuvre pour améliorer la reproductibilité des essais. Les études effectuées sur le modèle concernent d’une part l’identification des états de lithiation dans la cellule avec un attention particulière sur la précision obtenue, et enfin une prospection numérique pour examiner l’influence de chaque paramètre sur les réponses de la batterie en décharge galvanostatique puis en mode impulsion et relaxation<br>The future development of electric vehicles is mostly dependent of improvements in battery performances. In support of the actual research of new materials having higher performances in terms of energy, power, durability and cost, it is necessary to develop modeling tools. The models are helpful to simulate integration of the battery in the powertrain and crucial for the battery management system, to improve either direct (e.g. preventing overcharges and thermal runaway) and indirect (e.g. state of charge indicators) safety. However, the battery models could be used to understand its physical phenomena and chemical reactions to improve the battery design according with vehicles requirements and reduce the testing phases. One of the most common model describing the porous electrodes of lithium-ion batteries is revisited. Many variants available in the literature are inspired by the works of prof. J Newman and his research group from UC Berkeley. Yet, relatively few works, to the best of our knowledge, analyze in detail its predictive capability. In the present work, to investigate this model, all the physical quantities are set in a dimensionless form, as commonly used in fluid mechanics: the parameters that act in the same or the opposite ways are regrouped and the total number of simulation parameter is greatly reduced. In a second phase, the influence of the parameter is discussed, and interpreted with the support of the limit cases. The analysis of the discharge voltage and concentration gradients is based on galvanostatic and pulse/relaxation current profiles and compared with tested commercial LGC cells. The simulations are performed with the software Comsol® and the post-processing with Matlab®. Moreover, in this research, the parameters from the literatures are discussed to understand how accurate are the techniques used to parametrize and feed the inputs of the model. Then, our work shows that the electrode isotherms shapes have a significant influence on the accuracy of the evaluation of the states of charges in a complete cell. Finally, the protocols to characterizes the performance of commercial cells at different C-rates are improved to guarantee the reproducibility
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Richard, Marie-Hélène. "Design study of a Compton camera for prompts-gamma imaging during ion beam therapy." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00934715.
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Ion beam therapy is an innovative radiotherapy technique using mainly carbon ion and proton irradiations. Its aim is to improve the current treatment modalities. Because of the sharpness of the dose distributions, a control of the dose if possible in real time is highly desirable. A possibility is to detect the prompt gamma rays emitted subsequently to the nuclear fragmentations occurring during the treatment of the patient. In a first time two different Compton cameras (double and single scattering) have been optimised by means of Monte Carlo simulations. The response of the camera to a photon point source with a realistic energy spectrum was studied. Then, the response of the camera to the irradiation of a water phantom by a proton beam was simulated. It was first compared with measurement performed with small-size detectors. Then, using the previous measurements, we evaluated the counting rates expected in clinical conditions. In the current set-up of the camera, these counting rates are pretty high. Pile up and random coincidences will be problematic. Finally we demonstrate that the detection system is capable to detect a longitudinal shift in the Bragg peak of +or- 5 mm, even with the current reconstruction algorithm.
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Ehling-Schulz, Monika. "Physiological and protein-biochemical analysis of UV-A and UV-B tolerance of the terrestrial cyanobacterium Nostoc commune." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960206582.
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Gellatly, Judith. "Decision-making in stepped care for common mental health problems." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/decisionmaking-in-stepped-care-for-common-mental-health-problems(c7f8b1b3-2b2b-430a-a017-e6b9726709b1).html.
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Stepped care is designed to provide mental health treatment in the most effective and efficient way. It aims to provide patients with low intensity interventions in the first instance and only move onto high intensity treatments if outcome is not 'successful'. However, there is a paucity of research about how health professionals make decisions about treatment and the experiences of patients within this decision-making process. Using a multi-method approach, this study aimed to explore health professional and patient decision-making in stepped care for anxiety and depression. 24 health professional interviews from three stepped care sites were conducted, which included the completion of an active information search (AIS) think-aloud task. In addition, 14 patients were interviewed about their experiences of decision-making whilst being managed within stepped care model. Qualitative interview data was analysed using the principles of Framework analysis, while some of the data collected in the AIS think-aloud task lent itself to quantitative analysis.This study revealed that three core tensions exist when making decisions within the stepped care model. These are 1. The notion of standardisation of outcomes versus the individual needs of patients; 2. The public health orientation of stepped care versus the therapeutic orientation of health professionals and; 3. The rhetoric about patient choices versus the realities of shared decision-making in a resource-limited system.The complexity of decision-making within the stepped care model was highlighted. The success of stepped care relies on ensuring that there is an adequate workforce to deliver the intended interventions, where this is not present health professionals are faced with difficult decisions and it is clear that those most affected are the less-experienced frontline workers. Scarcity of resources impacts heavily upon the decisions that are made. This can have a substantial impact upon variability in treatment decisions and on the ability to allow for patient choice to be incorporated. Decisions that are made for a patient are influenced by the need to provide them with the treatment that they want (which may not be regarded as what they need within the stepped care model nor necessarily by the health professional) and the capacity of the service. The problem that exists with primary care mental health is that the current demands exceed capacity. Optimal patient care is, in part, traded off by the need to meet the demands of the service. Improving the flexibility of the service may be one solution to the problem and adopting a stratified/stepped care approach might help to resolve some of the tensions and help to relieve some of the capacity issues.
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Wienhues, Anna. "Life in common : distributive ecological justice on a shared earth." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/life-in-common-distributive-ecological-justice-on-a-shared-earth(f61a805d-5971-441c-826a-6be449c7f95d).html.
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This thesis lies in the overlap of environmental political theory and environmental ethics. More specifically, it focuses on the intersection between distributive ecological justice (justice to nature), and environmental justice (distributing environmental goods between humans). Against the backdrop of the current sixth extinction crisis, I address the question of what constitutes a just usage of ecological space. I define ecological space as encompassing environmental resources, benefits provided by ecosystems and physical spaces and when considering its just usage I not only take into account claims to ecological space held by other humans but also the demands of justice with regards to nonhuman living beings such as animals and plants. In order to address my overall research question, I look at three areas of inquiry in particular. My first area of concern is questions around how environmental justice can be made compatible with a theory of ecological justice. Here I defend a specific definition of ecological space and provide a critique of theories of justice that are based on the view that humanity has an original ownership of the Earth. Secondly, I defend a biocentric approach to distributive ecological justice based on all living beings constituting together a community of fate, and I additionally clarify the relationship between justice and biodiversity loss. Lastly, considering that the current situation of life on Earth does not resemble the circumstance of moderate scarcity where all needs could theoretically be met (as usually assumed by the most influential theories of justice), I inquire into how demands of environmental and ecological justice differ in different circumstances of scarcity, and what could be considered a just compromise between these two domains of justice. I then apply these last considerations to the Half-Earth proposal for creating large protected areas for nonhuman species, which has been advocated by E. O. Wilson and other ecologists as a means to slow the current rate of anthropogenic species extinctions. In essence, the Half-Earth proposal might be ambitious, but I argue there are good reasons to consider it as one building block of a (distributively) just future for life on Earth.
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Pope, Matthew. "The titanium(IV) oxide photocatalysed decomposition of some common pollutants in water and the influence of metal ions on the photocatalytic process." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387774.
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Ibragimov, Iskander. "Development of a readout electronic for a Si-pixeldetector for application in a Compton camera." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=97431563X.
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Nagel, Daniel Edwin. "3DShips : rapid 3D icon generation for the Command and Control Workstation of the Future." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/25645.
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Musiat, Peter. "Trait-focused internet-based prevention of common mental disorders in students." Thesis, King's College London (University of London), 2012. https://kclpure.kcl.ac.uk/portal/en/theses/traitfocused-internetbased-prevention-of-common-mental-disorders-in-students(1ceb4dc0-3ac6-4b32-b235-363c36257e9a).html.
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Background: Many university students experience symptoms of depression, anxiety disorders, substance use disorders or eating disorders. This thesis aimed to develop and evaluate a trait-focused internet-based prevention programme for these disorders in students. The thesis comprises of three studies. Study 1: In a cross-sectional study, 425 students were assessed on personality and mental health. A cluster analysis of indicators of mental health suggested two groups: one "high risk" group (20 per cent), who experienced symptoms of mental disorders; and the remaining students (80 per cent), who did not experience symptoms. Students at high risk showed higher trait anxiety, perfectionism and introversion/hopelessness. Study 2: To investigate challenges of student life, a mixed-methods study combined a web survey and focus groups. In the web survey, students most frequently identified social, practical and academic challenges. The focus groups confirmed these challenges and suggested that stigma and the belief that support mechanisms at university are only for students with severe problems would hinder support seeking. Study 3: Based on the findings from studies 1 and 2, a trait-focused internet-based cognitive-behavioural intervention was developed. This intervention included modules on perfectionism, low self-esteem, difficult emotions and anxiety. An active control intervention and a procedure for personalised feedback were developed. In a randomised controlled trial, the efficacy of the intervention compared to a control intervention was investigated in 1141 students, who were classified as high or low risk according to their personality. The trait-focused intervention reduced depression, anxiety and, to some extent, phobia-related avoidance and eating disorder symptoms in students at high risk. Conclusions: These findings suggest that: (a) students at high risk of developing mental disorders can be identified; (b) high risk students report higher levels of emotional and health difficulties; and (c) the mental health of these students can be improved with an intervention targeting personality risk factors.
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Masroor, Waliullah. "Coping with salinity and temperature changes : a focus on the gill response in European sea bass Dicentrarchus labrax." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG008/document.
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Le loup ou bar européen effectue une partie de son cycle de vie dans les lagunes et estuaires, des eaux de transitions caractérisées par des fluctuations environnementales plus marquées qu’en milieu marin. Les mécanismes d’acclimatation à la salinité à des températures plus élevées qu’en milieu marin sont encore relativement inexplorés. Dans cette étude, des juvéniles de loup ont été préacclimatés pendant deux semaines à l’eau de mer (EM) à 18 °C (eau tempérée) ou à 24 °C (eau chaude) puis transférés soit dans l’eau douce (ED) soit dans l’EM aux deux températures testées. À 24 °C, les loups parviennent à maintenir leur pression osmotique sanguine relativement constante, quelle que soit la salinité testée. En revanche, la hausse de température affecte significativement différents traits physiologiques liés à l’osmorégulation, la régulation acido- basique, l’excrétion azotée et la production de mucus. Cette étude a notamment montré qu’une acclimatation thermique à 24 °C modifie la structure morphologique de la branchie et induit un déséquilibre de la balance ionique sanguine. Ce déséquilibre concerne particulièrement les ions Na+ et a pour conséquence une diminution du ratio Na+/Cl- plasmatique, pouvant être symptomatique d’une acidose sanguine. Après transfert en douce, une augmentation moins importante de la densité des ionocytes branchiaux et de l’activité de la pompe Na+/K+ ATPase a été observée à 24 °C comparé à 18 °C. De plus, certains transporteurs ioniques jouant un rôle clé dans l’absorption ionique en eau douce n’ont pas été induits au niveau transcriptionnel à 24 °C. Cela suggère une capacité réduite des poissons de passer d’un épithélium branchial hypo-osmorégulateur vers un épithélium hyper-osmorégulateur lors d’un transfert en eau douce à 24 °C vs 18 °C. Au niveau moléculaire, la hausse de température a affecté l’expression de plusieurs transporteurs ioniques branchiaux, notamment en EM. À 24 °C, la surexpression de transporteurs liés au transport de proton H+ pourrait être le signe d’un déséquilibre acido- basique. De plus, l’induction de transporteurs d’ammonium pourrait indiquer un besoin accru d’excréter de l’azote par voie branchiale, potentiellement lié à un métabolisme plus élevé en eau chaude. L’expression des gènes codant pour la protéine chaperonne HSP90 a été fortement affectée par la hausse de température et dans une moindre mesure par la dessalure. Pour finir, l’analyse des mucocytes suggère que la production de mucus pourrait être induite en réponse au stress thermique. Ce type d’étude fonctionnelle sur l’acclimatation à différents régimes de température permet d’apporter des éléments de compréhension pour pouvoir prédire les réponses des téléostéens face aux conséquences du changement global<br>The European sea bass Dicentrarchus labrax undertakes seasonal migrations to estuaries and lagoons that are characterized by fluctuations in environmental conditions. It is unclear to what extent salinity acclimation mechanisms are affected at temperatures higher than in the sea, as usually encountered in transitional waters in spring and summer. In this study, juvenile sea bass were pre-acclimated to seawater (SW) at 18 °C (temperate) or 24 °C (warm) for two weeks and then transferred to either fresh water (FW) or SW at the considered temperatures. We have shown that sea bass are able to efficiently maintain blood osmolality at 24 °C at both salinities. However, temperature increase induced significant changes regarding several physiological traits related to osmoregulation, acid-base regulation, ammonia excretion and mucus production. This study showed that thermal acclimation at 24 °C affects gill morphology through gill remodeling and whole-organism ion balance. Plasma Na+ levels seemed to be particularly affected leading to decreased plasma Na+/Cl- ratio in warm conditions, suggesting a blood acidosis. Following FW transfer, the major effects observed were a lower increase in the density of branchial ionocytes and in Na+/K+-ATPase activity at 24 °C compared to 18 °C. Moreover, several key ion transporters involved in ion uptake were not transcriptionally induced following FW transfer at 24 °C. These data suggest a less effective capacity to switch from hypo-to hyper-osmoregulation after FW transfer when fish are exposed to higher temperature. At the molecular level, the temperature increase affected the expression of several branchial transporters, notably in SW. At 24 °C, higher expression of transporters linked to H+ transport might be linked to an acid-base imbalance. Moreover, the induction of ammonia-transporting channels might also indicate increased need for nitrogen excretion, potentially due to enhanced metabolism in warm conditions. Molecular chaperones HSP90 expression was strongly affected by temperature increase and to a lesser extent by salinity decrease. Finally, gill goblet cells analysis suggested that mucus production is increased in response to thermal stress. This study and additional functional studies investigating different temperature regimes provide insights on the effect of increased temperatures on fish responses and may help to predict how teleost will face the consequences of global change
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Dauvergne, Denis. "Processus de capture électronique par des ions lourds très épluchés canalisés dans des cristaux minces à des énergies supérieures à 20 MeV-nucléon." Lyon 1, 1993. http://www.theses.fr/1993LYO10069.
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Ce travail est consacre a l'etude des processus d'echanges de charge par des ions lourds canalises dans des cristaux minces a des energies superieures a 20 mev/nucleon. La canalisation d'ions lourds dans un cristal permet l'extinction des interactions a faible parametre d'impact avec les curs atomiques du cristal. Des processus d'echanges de charge qui sont minoritaires lors de collisions avec des cibles solides peuvent etre mis en evidence en canalisation, et meme devenir dominants, car la grande majorite des ions incidents interagit uniquement avec le gaz d'electrons de valence du cristal. C'est le cas de la capture dielectronique (en anglais resonant transfer and excitation, rte), processus resonnant dans lequel la capture est accompagnee de l'excitation d'un electron de cur du projectile, et de la capture electronique radiative (rec). L'ensemble des processus d'interaction ion-electron observables en canalisation sont presentes dans le premier chapitre. Les chapitres suivants decrivent deux experiences, realisees dans la voie lise de l'accelerateur ganil de caen: la premiere experience est consacree a l'etude de la resonance kll-rte d'ions xe#5#2#+ canalises le long de l'axe <110> d'un cristal de 21 m de silicium, a des energies variant de 34 a 43 mev/nucleon; la seconde presente l'etude de la capture rec-k par des ions kr#3#6#+ de 60 mev/nucleon canalises dans un cristal de 37 m de silicium oriente selon l'axe <110>. Ces deux experiences ont permis de faire une etude detaillee des distributions en impulsion des electrons de valence du cristal, dans la direction particuliere de propagation de l'ion incident canalise (profils compton)
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El-Sheikh, Amr Abdelhamid Farag. "Decreased IFN-gamma message by pancreatic islet-infiltrating leukocytes is a common feature of different treatments that protect against autoimmune diabetes in the BB rat." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0025/NQ34758.pdf.
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Medhin, Tesfay Girmay. "Modelling the effect of common mental disorders on child growth in Butajira, Ethiopia." Thesis, King's College London (University of London), 2012. https://kclpure.kcl.ac.uk/portal/en/theses/modelling-the-effect-of-common-mental-disorders-on-child-growth-in-butajira-ethiopia(400d1ebc-cd49-4b0d-8f84-25127d376d04).html.
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Background: Evidence about the effects of perinatal common mental disorders (CMD) on child growth is consistent in South Asian studies but not in Sub Saharan Africa. Aims: To (1) assess the effect of CMD on child growth in Ethiopia using traditional analysis, latent growth modelling (LGM) and multilevel growth modelling (MGM) techniques, and (2) evaluate the effects of other pre-specified risk factors on infant growth using these three modelling techniques Methods: A population based cohort was established between July 2005 and February 2006 in a demographic surveillance site in Butajira, Ethiopia, recruiting 1065 women in pregnancy and followed them with their newly born infants. Main exposure was perinatal CMD measured with locally validated self reporting questionnaire (SRQ-20). The women were interviewed at recruitment, birth, two and 12 months postnatal. In addition to birthweight, infant growth was monitored at two, six, nine, 12 and 18 months of age and standardized using 2006 WHO reference standards. Logistic regression and linear regression were used to model binary and continous infant growth outcomes, respectively, at two, six and twelve months of age. Furthermore, infant growth over the first 18 months of age and predictors of growth patters of these infants were investigated using MGM and LGM. Results: Postnatal and persistent CMD were significant risk factors of compromised initial infant length, and part of the effect on the total length gain was mediated through diarrhoeal episodes. Early infant feeding practices and birthweight did not mediate the effects of CMD on infant growth. Boys perform better in initial weight (in kg) and length (in cm), but worse in initial values of standardized growth measures. Low birthweight and reduced maternal mid upper arm circumference during pregnancy were significant predictors of compromised initial growth.
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Qadir, F. "Gender disadvantage as a risk factor for common mental disorder in women residing in Rawalpindi/Islamabad." Thesis, King's College London (University of London), 2005. https://kclpure.kcl.ac.uk/portal/en/theses/gender-disadvantage-as-a-risk-factor-for-common-mental-disorder-in-women-residing-in-rawalpindiislamabad(3a806ea8-69a6-4461-a595-3ef8198df6a8).html.
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I assessed common mental disorder (CMD) and its association with gender disadvantage among young women in two defined catchment areas (with contrasting socio-economic circumstances) in each city. Socio-economic status is a risk factor for CMD, and may confound or modify the effect of gender disadvantage, hence the stratified sampling. Female gender disadvantage cannot be measured directly, but is a well recognized phenomenon and has important effects across the life course. I used five proxy indicators; 1) no older brother at the time of birth (as a proxy for male preference), 2) limited parental bonding (low care and high overprotection), 3) low educational attainment 4) adverse marital circumstances (early age at marriage and low satisfaction) and 5) subjective perception. Recruitment and interviewing of 525 women aged 20-35 was completed with 98% response rate. 57% were married. The prevalence of CMD (SRQ score >=8) ranged from 26% (high SES Rawalpindi) to 83% (low SES Islamabad). Perception of parental preference for males, low care, less education, early age at marriage and low marital satisfaction were, as hypothesised, strongly correlated. I have found strong effects of all of the indicators of gender disadvantage (other than birth order) upon risk for CMD, independent of SES. I found strong evidence to support the main hypothesis of an independent association between low care and increased risk for CMD. However, for this risk factor the effect was modified by SES being significantly stronger among those living in higher SES districts.
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Faucher, Karine. "Le système latéral du bar, Dicentrarchus labrax, et les conséquences d'un dysfonctionnement sur son comportement : action potentielle des ions métalliques." La Rochelle, 2004. http://www.theses.fr/2004LAROS124.
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Le système latéral est un organe sensoriel présent chez les amphibiens aquatiques et les poissons. Il est utilisé par les poissons pour l'identification et la localisation d'obstacles, la détection des objets en mouvement (proies, prédateurs), la détection des vibrations générées par les ondes sonores, la communication intraspécifique (nage en banc, parade sexuelle) et la rhéotaxie. L'intégrité morphologique et fonctionnelle de ce système sensoriel apparaît donc comme un élément indispensable à la présence et à la survie d'un poisson dans un écosystème. Or, de part sa localisation à l'interface entre l'animal et le milieu, et le fait qu'il fonctionne via des flux d'ions, cet organe sensoriel exposé directement et en permanence au milieu ambiant pourrait être la cible d'une pollution d'origine naturelle ou anthropique. Le but de cette étude était d'examiner l'impact d'une pollution métallique (et en particulier, de l'ion cadmium) du milieu sur l'état tissulaire et fonctionnel du système latéral du bar, Dicentrarchus labrax (L. ), puis d'observer les conséquences comportementales induites sur des groupes d'individus évoluant dans des conditions contrôlées de laboratoire. Une étude préliminaire des caractéristiques morphologiques et de la distribution spatiale des deux types de neuromastes composant le système latéral du bar a été réalisée à l'aide de la microscopie électronique à balayage. Comme ce qui a été généralement observé chez les téléostéens, le bar possède deux types de neuromastes (superficiels et canaux) répartis sur la tête, le tronc et la queue. Le gradient décroissant de capacité sensorielle, mis en évidence de l'extrémité rostrale à l'extrémité caudale de la ligne latérale troncale du bar, est très original et pourrait jouer un rôle dans le fonctionnement du système latéral. L'axe de sensibilité majeure des deux types de neuromastes du système latéral troncal a été identifié dans l'axe longitudinal du poisson, ce qui lui octroie une sensibilité accrue aux stimuli appliqués le long de son corps. Afin de révéler les conséquences comportementales liées à un dysfonctionnement du système latéral du bar, les deux types de neuromastes ont été endommagés artificiellement. Pour cela, une double technique spécifique, efficace, reproductible et peu invasive pour le poisson a été mise au point afin de dégrader au maximum ce système sensoriel. Cette méthode alliait la section des nerfs innervant le système latéral et un bain antibiotique. Les résultats obtenus indiquent que l'inactivation du système latéral du poisson entraîne une réduction de son comportement d'exploration verticale de l'habitat. Par contre, l'inactivation de ce système sensoriel n'a pas d'effet sur la prise alimentaire nocturne du poisson lorsque cette prise est constituée de proies inertes, un système de compensation sensorielle s'appuyant sur le système olfactif se met en place très rapidement. Les conséquences comportementales d'une exposition aiguë du bar à l'ion métallique cadmium ont ensuite été examinées. Cette étude a montré que le cadmium à forte concentration dans l'eau de mer (5 µg. L-1) a un effet inhibiteur sur la réponse de fuite des poissons face à un danger. Cet effet comportemental s'accompagne de la destruction des deux types de neuromastes composant le système latéral observé en microscopie électronique à balayage. Après 21 jours, on constate une régénération des tissus des neuromastes, ainsi qu'une restauration du comportement de fuite des poissons. Par contre, lors de l'exposition aiguë au cadmium à la concentration rencontrée en milieu naturel contaminé (0,5 µg. L-1), le comportement de fuite du poisson n'est pas modifié et les tissus des neuromastes demeurent intacts. Cependant, les stimuli appliqués lors de cette étude pour simuler un danger au poisson étant relativement forts, on peut donc se demander si après une exposition aiguë au cadmium à 0,5 µg. L-1, le bar serait toujours capable de détecter le mouvement subreptice d'une proie vivante mobile. Ce travail mériterait d'être poursuivi par des études visant à déterminer la concentration seuil de cadmium responsable de dommages tissulaires au niveau des neuromastes et celle causant des désordres comportementaux. Il serait également intéressant d'examiner l'effet synergique des ions métalliques présents dans le milieu naturel (cadmium, cobalt, cuivre, mercure, nickel, plomb, zinc, etc. . . . ) sur le système latéral du bar et le comportement de cette espèce<br>The lateral system is a sensory organ found in aquatic amphibians and fish. It is used by fish for obstacle identification and localization obstacles, for moving objects (preys, predators) detection, for the detection of vibrations generated by low-frequency sound waves, for intraspecific communication (shoaling and sexual parade) and rheotaxis. The functional and morphologic integrity of this sensory system appears thus as an indispensable element for the presence and the survey of fish in an ecosystem. By its localization at the interface between the animal and the environment, and the fact that it functions via ion flux, this sensory organ, directly and constantly exposed to ambient medium, could then be the target of a natural or anthropic pollution. The aim of this study was to examine the impact of an environmental metallic pollution (and in particular, the cadmium ion) on tissues and function of the sea bass, Dicentrarchus labrax (L. ) lateral system, then to observe behavioral consequences induced on individual groups evolving in laboratory controlled conditions. A preliminary study concerning morphologic characteristics and spatial distribution of both types of neuromasts composing the sea bass lateral system was realized using scanning electron microscopy. As usually observed in teleosts, the sea bass possesses two types of neuromasts (superficial and canal ones) distributed on the head, trunk and tail. The decreasing gradient of sensory capacity, underlined from the rostral to the caudal ends of the sea bass trunk lateral line system, is really original and could be involved in the lateral system function. The major sensitivity axis of both types of neuromasts from the trunk lateral line system was identified along the fish's long axis, which confers itself a greater sensitivity of stimuli applied along its body. To reveal the behavioral consequences related to a sea bass lateral system dysfunction, both types of neuromasts were artificially damaged. For this, a double specific, efficient, reproducible and few invasive technique for fish was developed in order to alter at most this sensory system. This method combined the lateral system nerves section with an antibiotic bath. The results indicate that the fish lateral system inactivation involves a reduction of its habitat vertical exploration behavior. In contrast, the fish lateral system inactivation has no effect on the fish nocturnal demand feeding when stationary preys constitute food. A sensory compensation system leaning on olfactive system sets very quickly. The behavioral consequences of an acute exposition of sea bass to cadmium ions were then investigated. This study has shown that cadmium at high concentration in seawater (5 µg. L-1) has an inhibitory effect on the fish startle response facing a danger. This behavioral effect goes along with the destruction of both types of lateral system neuromasts observed in scanning electron microscopy. After 21 days, we notice tissue neuromast regeneration as well as fish startle response restoration. In contrast, when exposed to cadmium at the concentration of the contaminated natural environment (0,5 µg. L-1), fish startle response was not modified and neuromast tissues remain intact. However, in this study, the stimuli applied to simulate a danger to fish being of relatively high intensity, we can wonder if after an acute exposition to cadmium at 0,5 µg. L-1, the sea bass will be always able to detect the surreptitious movement of an alive moving prey. This work would earn to be pursued by studies aiming at determining the cadmium threshold concentration responsible to neuromast tissue damages and the one causing behavioral disorders. It would be also interesting to examine the synergetic effect of metallic ions present in natural environment (cadmium, cobalt, copper, lead, mercury, nickel, zinc, etc. . . ) on the sea bass lateral system and on this species behavior
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Ghio, Daniela. "Illness perceptions in adolescents with juvenile arthritis : applying the common sense self-regulatory model." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/illness-perceptions-in-adolescents-with-juvenile-arthritis-applying-the-common-sense-selfregulatory-model(ec4d78b7-1cdd-463d-9861-1da30d5a72ed).html.
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Background: Juvenile idiopathic arthritis (JIA) is a long-term inflammatory arthritis which starts before the age of 16; 60% of those with JIA continue to have symptoms into adulthood. There are wide variations in experiences of adolescents with JIA, including the effects of the condition on social and intellectual development, self-management, psychological and physical functioning. Individual differences may be due to differences in how adolescents conceptualise JIA. Leventhal's Common Sense Self-regulatory Model (CS-SRM) has been used to theorise adults' experiences of illness, however, this has rarely been used with adolescents. The CS-SRM has three components, mental representations (component 1) that drive coping procedures and illness behaviours (component 2) which are then evaluated and appraised (component 3). A review of studies with adolescent cohorts that applied the CS-SRM found no evidence-base with which to justify application of an adult theory with children or adolescents. Thus the applicability of the theory and the use of the associated questionnaire, the Revised Illness Perceptions Questionnaire (IPQ-R), with adolescents are problematic. Aims: The aims of this PhD were first to assess the suitability of the CS-SRM for adolescents with JIA by investigating the three components of the model, and second, to develop a questionnaire for use with this population. Methods: To investigate the first two components of the CS-SRM, twenty-one participants aged between 11-16 years were recruited from a national cohort of JIA patients. Data collection was undertaken using cognitive interviewing. Framework analysis of the data was used to identify domains used by adolescents to conceptualise their JIA and content analysis to further investigate the suitability of the IPQ-R to assess beliefs. Transcripts were analysed identifying problems or inconsistencies with IPQ-R use. Adolescents' ways of coping with JIA were investigated using the somatic experience module of a computer-based interview, 'In My Shoes' (IMS). To evaluate the third component of the CS-SRM, quantitative data were used in a longitudinal mediation analysis to investigate the extent to which emotional representations and pain predicted physical behaviour (n= 50). To address the second aim of this PhD, Version 1 of the Pain Perception Questionnaire for Young People (PPQ-YP) was devised and sent to 18 healthy adolescents (11- 16) to assess linguistic validity and face validity of the items using a recent pain to answer items and provide feedback on language and length. The psychometric properties of a revised version were tested with 76 adolescents with JIA. Results: Adolescents' responses to having JIA were driven by their emotional and cognitive responses to symptoms (in this case pain) rather than illness beliefs per se. Thus, it is important to assess pain beliefs rather than broader illness representations. The need to preserve their social identity as 'normal' was a coping goal shared across the sample, however different strategies were identified, either to focus on maintaining normal activities or to attend to pain directly. Adolescents who focused on their pain held a more negative emotional representation, reported higher pain and lower functionality compared to adolescents who tried to maintain normality. Based on these results, longitudinal mediation models investigated the role of emotional representations and pain in predicting physical behaviour. Pain mediated 44% of the relationship between emotional representations and physical behaviour. Conclusions: Modifications to the model are recommended to take into account the role of social identity in the process of developing illness behaviours as well as the importance of a symptom driven conceptualisation of the condition.
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Tesrif, Moulay Mustapha. "La šu'ubiyya et la recherche d'un passé mythique commun dans l'adab du IIIe/IXe siècle : exemples d'al-Gahiz et d'Ibn Qutayba." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE2138.
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Cette thèse se propose de montrer, à partir d’exemples concrets de textes anti-Šu‘ūbiyya tirés des œuvres d’al-Ğāḥiẓ (m. 255/869) et d’Ibn Qutayba (m. 276/889), la prégnance de la période préislamique sur l’adab du IIIe/IXe siècle. La méthode retenue est la confrontation critique notamment de la version numérisée de ces textes. Cette approche permet d’alimenter l’hypothèse d’une représentation magnifiée de l’Arabie préislamique : une image qui a fondé une part non négligeable des symboles identitaires de la culture arabo-musulmane, nourrie d’un passé mythique dans lequel peuvent se retrouver tous les musulmans sans préjuger de leurs ascendances.En effet, entendant par « mythe » les récits des origines qui cherchent à expliquer des données de la réalité en les inscrivant dans une dimension transcendée et surnaturelle, le symbolisme de l’adab situe l’essence des valeurs qu’il défend dans l’héritage des anciens Arabes. Cherchant à expliquer le monde, les udabā’ feront de la ğāhiliyya la source des vertus et le berceau de la langue arabe la plus pure. Inventant de nouvelles généalogies « fédératrices », ils s’attacheront à mettre en avant la maîtrise des traditions arabes préislamiques. Ainsi, nos deux auteurs situent la naissance de la civilisation arabo-musulmane dans des récits hors du temps et en rupture avec le présent. Les musulmans non-arabes peuvent donc ne plus se réclamer de leurs passé « réaliste » et prendre plutôt racine dans un passé qui favorise une culture commune inscrite dans un temps autre que le temps historique. Nos auteurs inventent une manière de culture vierge qui, seule, peut permettre à leurs yeux le commencement absolu. Par conséquent, les référents à la supériorité devraient être bouleversés par « l’effet anti-Šu‘ūbiyya » puisque l’origine ethnique ou la réalité historique ne sont plus le seul sens de l’existence<br>Based on concrete examples from anti-Šu‘ūbiyya texts pulled from works of al-Ğāḥiẓ (d. 255/869) and Ibn Qutayba (d. 276/889), this thesis aims to demonstrate the pre eminence of the pre-Islamic period on the adab of the IIIe/IXe century. From a methodology which consists in a critical confrontation between these texts (especially the digitalized version of the texts), our point is to fuel the hypothesis of an adorned representation of pre-Islamic Arabia : This image produced a very important part of identical symbols of the Arab-Muslim culture, based on a mythical past in which all the Muslims without prejudice to their ancestries can find themselves."Myth" meaning the narratives of the origins created to explain data of the reality by registering them in a transcent and supernatural dimension, the symbolism of the adab places the essence of the values it is based on in the inheritance of the former Arabs. Trying to explain the world, the udabā’ made of the ğāhiliyya the source of the virtues and the cradle of the purest Arabic language. They devised new common genealogies to put forward the knowledge of the pre-Islamic Arabic traditions. Our two authors stand out the birth of the Arab-Muslim civilization in timeless narratives and in breach with the present time. Thus the non-Arabic Muslims can not refer anymore to their "historical" past and to take rather roots in a past which supports a common culture registered in a not historical time. Only this kind of blank culture, invented by our two authors, could allow the absolute beginning. Consequently, the markers of the supposed superiority could be shaken by the "anti-Šu‘ūbiyya effect" since the ethnical origin or the historical reality are not the only sense of the existence anymore
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Gamelin, Alexis. "Collective effects in a transient microbunching regime and ion cloud mitigation in ThomX." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS276/document.
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La thèse est axée sur l'étude des effets collectifs dans un anneau de stockage d'électrons de 50 MeV, ThomX, en l'absence d'amortissement synchrotron et d’adaptation longitudinale. Cette thèse est divisée en deux parties distinctes. La première partie correspond à la conception du modèle d'impédance (champ de sillage géométrique, résistif et rayonnement synchrotron cohérent) de l'anneau de stockage afin de simuler la dynamique faisceau. Le modèle d'impédance géométrique de l'anneau de stockage a été obtenu par la simulation des éléments individuels et a été vérifié en utilisant des mesures RF sur des prototypes. Le rayonnement synchrotron cohérent a été simulé en tenant compte d'une chambre à vide rectangulaire. Des simulations de la dynamique faisceau, de la cathode de canon RF à l'anneau de stockage, comprenant les effets collectifs sont présentées. Les simulations sont utilisées pour optimiser la dynamique faisceau dans l'anneau de stockage dans le régime de micro-paquet. La deuxième partie concerne l'étude du nuage d'ions produit par l'ionisation des molécules du vide résiduel et l'optimisation des techniques de nettoyage des ions. Les points d'accumulation longitudinaux des ions et le piégeage dans les champs magnétiques sont tous les deux étudiés analytiquement et en utilisant un programme développé à cet effet. Les électrodes de nettoyage et les espaces de nettoyages sont simulés et optimisés en utilisant ce code et la stratégie choisie pour la limitation des effets induits par les ions est décrite. Enfin, les effets de la multi-ionisation et de la dissociation ionique sont pris en compte et l'effet des ions sur le faisceau d'électrons est estimé<br>The thesis is focused on the study of collective effects in a 50 MeV electron storage ring, ThomX, in the absence of synchrotron radiation damping and of longitudinal matching. This thesis is divided in two distinct parts. The first part corresponds to the design of the impedance model (geometric and resistive wakefields, coherent synchrotron radiation) of the storage ring in order to simulate the beam dynamics. The geometric impedance model of the storage ring was obtained via simulation of the individual elements and was checked using wire measurements on prototypes. The coherent synchrotron radiation was simulated taking into account a rectangular vacuum chamber. Beam dynamics simulations, from the RF gun cathode to the storage ring, including collective effects are presented. The simulations are used to optimise the beam dynamics in the storage ring in the micro-bunching regime. The second part is the study of the ion cloud produced by the ionisation of the residual vacuum molecules and the optimisation of the ion clearing techniques. The longitudinal ion accumulation points and the trapping in magnetic fields are both studied analytically and by using a tracking code developed for this purpose. Clearing electrodes and clearing gaps are simulated and optimised using this code and the strategy chosen for the limitation of ion induced effects is described. Finally, the effect of multi-ionisation and ion dissociation is taken into account and the ion effect on the electron beam is estimated
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Charles, Kelvin. "The common in Hardt and Negri : substantiating the concept through its urban, digital and political moments." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/the-common-in-hardt-and-negri-substantiating-the-concept-through-its-urban-digital-and-political-moments(fc091265-6fb3-43cf-99f4-6bc0510a8bdb).html.
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The concept of the common, found in Hardt and Negri, provides the possibility of theorising struggle that avoids the critiques that suggest Empire remains intangible, ethereal and postmodern. The concept, however, remains fragmentarily developed by the authors themselves, and is rarely the subject of sustained analysis in the secondary literature. Therefore, in order to substantiate the concept, I consider the common through three distinct moments which I identify as the urban, digital and political moments. This task is achieved through theoretical interlocutions and reflections on the 2011 Occupy movement. Throughout this thesis, and through each moment of the common, I argue that the concept must be understood as distinctly physical. Firstly, struggles over the urban common revolve around the physical (re)production of ideas, knowledge, culture and relationships in urban environments. Whilst the digital common often implies a lack of physicality, I argue that the common offers a means of thinking social media and perpetual connectivity primarily as a process of transforming the way humans engage with one another and their environments, and the radical possibilities therein. I argue that these moments of the common necessitate the development of an appropriate political moment of the common. Through centring on the physicality of struggle, Hardt and Negria's concept of the common is substantiated whilst contributing to wider debates in the field of radical theory and social movements.
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Fiedler, Sabine. "ELF and the alternatives (Kommentar): Comments on Ian MacKenzie’s “Topic & Comment” in JELF 2014; 3(2): 395–407." De Gruyter, 2015. https://ul.qucosa.de/id/qucosa%3A31180.
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In his paper “ELF and the alternatives” Ian MacKenzie considers a number of options that are presently under discussion as possible alternatives to the use of
English as a Lingua Franca (ELF). Their scope includes translation (a short section of two paragraphs only), code switching, receptive multilingualism,
and Esperanto. It is the presentation of the latter approach that I want to address in this comment. As MacKenzie ’s bibliography contains two articles of mine and
as these seem to be important sources on which the author bases his argumentation, I suppose that I should react to his paper.
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Braunholtz-Speight, Timothy Herford. "Power and community in Scottish community land initiatives." Thesis, University of the Highlands and Islands, 2015. https://pure.uhi.ac.uk/portal/en/studentthesis/power-and-community-in-scottish-community-land-initiatives(7670cf12-6c48-41ef-8bdd-a5aac301873b).html.
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This thesis examines Scottish community land ownership through the lenses of power and community. It asks what impact Community Land Initiatives (CLIs) have on power relations, particularly at local level; and, if and how their conception as “community” initiatives affects that. These questions are addressed through in-depth qualitative case studies of two emerging CLIs on the Isle of Skye, in the context of the wider community land movement. The thesis finds that one of the CLIs studied have contributed some measure of additive empowerment to local residents. These are increasing in significance and social reach as the scale of asset ownership and associated development projects expands. The other is at an earlier stage in terms of land ownership, but has some collective power through a focus on the cultural and convivial aspects of community that has considerable local resonance. It is also clear that, where CLIs acquire land and assets, they shift visible power from landowners to community groups. They also are beginning to shift cultural perceptions of who and what land is for. However, despite some efforts by activists to address them, power relations at local level shape participation in CLI decision-making spaces. These are closely connected to experiences and ideas of community at local level. More broadly, the thesis shows how CLIs owe their power both to organising at local level, and to a network of relationships with actors elsewhere, including funding and support agencies. Maintaining and balancing all these relationships can be challenging. As an in-depth but narrowly focussed case study, this thesis aims at exploring these issues, rather than producing definitive judgements about the entire community land movement. The final chapter therefore situates the thesis in the context of other studies of this movement, and within the wider literature on power and development. It concludes with suggestions for further research and testing of the ideas it has developed.
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Gueye-Follet, Marie-Laure. "Relations ioniques dans l'activité cambiale et la xylogénèse : approche par microscopie ionique analytique." Rouen, 1997. http://www.theses.fr/1997ROUES050.
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Ce mémoire présente une approche par Microscopie Ionique Analytique (MIA) des relations ioniques dans l'activité cambiale et la xylogénèse chez deux modèles expérimentaux : le pin sylvestre (pinus sylvestris L. ) Et le hêtre (fagus sylvatica L. ). Ce travail comporte des mises au point méthodologiques concernant la préparation des échantillons ligneux et les conditions instrumentales de l'analyse en MIA. Nous avons mis au point une nouvelle méthode de préparation des échantillons végétaux, la fixation - déshydratation en phase vapeur, qui assure une bonne conservation des ultrastructures cellulaires et une bonne rétention des éléments diffusibles, comparativement à la technique de préparation par précipitation au pyroantimoniate. Les conditions de mise en oeuvre de l'analyseur ionique ont été spécifiquement établies sur notre matériel biologique et ont permis d'effectuer des analyses semi-quantitatives des distributions ioniques à l'échelle tissulaire et cellulaire. Les distributions saisonnières de Ca et de Na dans le tissu cambial et les tissus conducteurs voisins ont été étudiées sur des rameaux de hêtre et de pin sylvestre. La valeur du rapport de concentration Ca/Na est fortement corrélée à l'âge des organes caulinaires, un rapport Ca/Na élevé caractérisant les tissus des organes matures à activité cambiale intense, un rapport Ca/Na faible les tissu des organes jeunes à activité cambiale modérée. Nous avons montré qu'une augmentation temporaire du calcium dans le cambium et le liber est impliquée dans les processus conduisant à la reprise de l'activité cambiale chez le hêtre. La distribution de Ca, Na, Mg et K a été explorée lors des processus de maturation pariétale secondaire chez des plantules de hêtre se développant sur des milieux minéraux de composition variés. Lors d'une culture sur un milieu normal, les résultats obtenus par MIA ont montré que les cellules à épaississements pariétaux secondaires présentaient des teneurs en calcium beaucoup plus faibles que celles observées dans les cellules ne présentant que des parois primaires. Par contre, les teneurs en calcium dans les structures pariétales secondaires sont augmentées lorsque l'on fait varier les concentrations en sodium dans le milieu de culture (privation ou apport de Na). Dans le cas d'un apport de NaCl de 20 mM, les dépôts secondaires au niveau des parois des cellules du xylème secondaire et des fibres libériennes, sont absents. De plus, nous avons enregistré des augmentations importantes des teneurs en sodium, mais aussi en potassium, magnésium et calcium dans ces cellules où les dépôts pariétaux secondaires se seraient normalement formés. Bien que l'implication du calcium dans les processus de différenciation pariétale soit déjà connue, cette approche par MIA révèle une étroite interdépendance entre le calcium et les autres cations majeurs (sodium, potassium et magnésium) dans ces processus. L'ensemble de ces ions fait partie d'un système intégré, dans lequel des modifications d'un composant perturbe l'intervention des autres dans les mécanismes physiologiques étudiés.
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Thorneloe, Rachael Jane. "Investigating medication adherence in psoriasis : exploring the role of illness perceptions, medication beliefs, and emotional distress." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/investigating-medication-adherence-in-psoriasis-exploring-the-role-of-illness-perceptions-medication-beliefs-and-emotional-distress(758e5322-438d-4806-bd2c-84e39c6477dd).html.
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Objectives: Psoriasis is a long-term inflammatory condition associated with considerable psychological and social morbidity. There are multiple psoriasis treatment modalities and regimens making medication adherence particularly demanding. The Self-Regulatory Framework has not been widely applied to investigate adherence by people with psoriasis. This thesis reports research into psychological factors associated with medication adherence in psoriasis. Methods: A systematic review of adherence to treatments (Phase 1) was followed by a qualitative investigation of measures of adherence and treatment beliefs (Phase 2). A large-scale multisite quantitative survey of levels and determinants of adherence to systemic psoriasis treatments was carried out by linking new psychological measures with data from a national treatment registry (Phase 3). Finally a mixed-methods investigation into self- regulatory approaches to the understanding of adherence was undertaken (Phase 4). Findings: i) Adherence difficulties are prevalent in psoriasis, however poor methodology quality of previous studies limited conclusions of the systematic review ii) Patients using topical preparations described significant day-to-day variations in medication use as well as complex treatment decision-making processes; however, key behaviours and cognitions were not accurately reflected by corresponding scores of the standardised scales iii) Patients using systemic treatments reported high levels of adherence which were associated with: biologic rather than a traditional systemic; fewer concerns about systemic treatments; and lower PASI and DLQI scores. Unhealthy lifestyle behaviours were also prevalent iv) Effective treatment usage in psoriasis conflicted with the management of the physical and psychological demands of living with psoriasis. For patients using topical preparations, non-adherence was a strategic decision to reduce distress and gain control. Patients using systemic treatments expressed strong beliefs in the necessity of their treatment, yet reported high levels of anxiety and depression. Systemic treatment usage conflicted with the management of illness controllability and psychological adjustment. A more negative illness belief profile and greater appearance concerns accounted for the most variance in both anxiety and depression, even after controlling for disease severity. These findings have major implications for the measurement of adherence and treatment beliefs, as well as researchers’ ability to determine clinical outcomes and treatment response. Conclusions: Psoriasis treatment adherence can be practically challenging as well as emotionally charged. The construct of self-regulatory failure proved to be illuminating and improves understanding of the psychological processes that underpin medicines adherence and other aspects of self- management in people with psoriasis.
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Aseem, Saadia. "Development and evaluation of a psychosocial intervention for common mental disorders for the British South Asians in the UK." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/development-and-evaluation-of-a-psychosocial-intervention-for-common-mental-disorders-for-the-british-south-asians-in-the-uk(3ac9b949-8a1e-4453-8928-1b0975add315).html.
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Background: Ethnic minorities, particularly the South Asian community, have a high prevalence of depression within the United Kingdom (UK). They suffer from poor health, social isolation and tend to not access available health services and treatment. Culturally appropriate psychosocial interventions are effective for depression. However, in the UK, very limited research evidence is available to date. The research study focuses on the processes involved with the aim of developing and evaluating the acceptability, adherence and effectiveness of a culturally appropriate psychosocial intervention for the South Asians in the UK.Methods: A phased programme of research was planned to achieve the aims. In the first phase, a systematic review was conducted. The aim was to identify and synthesize the literature on effective psychosocial interventions for common mental disorders, particularly for ethnic minorities in developed countries. In the second phase, four focus groups from which three with ethnic minority service users and one with the health professionals were conducted. The purpose was to collect and understand the views of South Asian service users and providers in order to culturally adapt an intervention as part of the AMP programme. In the final phase of the study, seventeen qualitative interviews were conducted with the psychosocial intervention trial participants and the intervention provider team. The case studies were analysed to evaluate the delivery, acceptability, adherence and cultural appropriateness of the psychosocial intervention. Findings: The systematic review provides reasonable evidence from trials and subgroup analyses from trials that ethnic minority patients could benefit from modified psychological treatments. However, there is no systematic documentation of cultural adaptations available. The participants of the focus groups and evaluation interviews identified cultural specific and universal barriers and highlighted cultural sensitive modifications for interventions which the health care providers need to respond in order to make mental health care accessible for the ethnic minorities. The qualitative studies show evidence that cultural adaptations improve acceptability and adherence in interventions. The findings highlighted empathy as the significant need of the participants of the well-being intervention. People make choices depending on the intensity of their need, the nature of the problem and the options available to them. The participants suggested that fulfilment of needs is vital rather than assuming that cultural matching is always necessary. Conclusion: Culturally modified interventions for specific populations can improve acceptability and accessibility. Better engagement and adherence to psychosocial interventions can be achieved by overcoming culturally specific and universal barriers and by providing treatment choices to patients according to the nature and urgency of their specific need. Further research is required for developing an evidence base in respect of designing effective mental health treatments for minority patients. A systematic way of documenting all these adaptations is essential. It would enable progress by improving comparability and replication of modifications across studies.
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Jaber, Maysaa Husam. "Sirens in command: the criminal femme fatale in American hardboiled crime fiction." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/sirens-in-command-the-criminal-femme-fatale-in-american-hardboiled-crime-fiction(a6a35b81-665e-4f1a-9f3c-a8c286fe3796).html.
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This thesis challenges the traditional view of the 'femme fatale' as merely a dangerous and ravenous sexual predator who leads men into ruination. Critical, especially feminist, scholarship mostly regards the femme fatale as a sexist construction of a male fantasy and treats her as an expression of misogyny that ultimately serves to reaffirm male authority. But this thesis proposes alternative ways of viewing the femme fatale by showing how she can also serve as a figure for imagining female agency. As such, I focus on a particular character type that is distinct from the general archetype of the femme fatale because of the greater degree of agency she demonstrates. This 'criminal femme fatale' uses her sexual appeal and irresistible wiles both to manipulate men and to commit criminal acts, usually murder, in order to advance her goals with deliberate intent and full culpability. This thesis reveals and explains the agency of the criminal femme fatales in American Hardboiled crime fiction between the late 1920s and the end of World War II in the works of three authors: Dashiell Hammett, Raymond Chandler and James M. Cain. The criminal femme fatales in the narratives of these authors show a subversive power and an ability to act - even though, or perhaps only if, this action is a criminal one. I show that these criminal femme fatales exhibit agency through their efforts to challenge not only the 'masculine' genre and the criminal space that this genre represents, but also to undercut the male protagonist's role and prove his failure in asserting control and dominance. Hammett's narratives provide good examples of how the criminal femme fatales function on a par with male gangsters in an underworld of crime and corruption. Chandler's work demonstrates a different case of absent/present criminal women who are set against the detective and ultimately question his power and mastery. Cain's narratives show the agency of the criminal femme fatales in the convergence between their ambition for social mobility and their sexual power over the male characters. To explain how these female characters exhibit agency, I situate this body of literature alongside contemporaneous legal and medical discourses on female criminality. I argue that the literary female criminal is a fundamentally different portrayal because she breaks the 'mad-bad' woman dichotomy that dominates both legal and medical discourses on female criminality. I show that the criminal femme fatales' negotiations of female agency within hardboiled crime fiction fluctuate and shift between the two poles of the criminalized and the medicalized women. These criminal femme fatales exhibit culpability in their actions that bring them into an encounter with the criminal justice system and resist being pathologized as women who suffer from a psychological ailment that affect their control. The thesis concludes that the ways in which the criminal femme fatales trouble normative socio-cultural conceptions relating to docile femininity and passive sexuality, not only destabilize the totality and fixity of the stereotype of the femme fatale in hardboiled crime fiction, but also open up broader debates about the representation of women in popular culture and the intersections between genre and gender.
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Bollon, Nicolas. "Étude critique de la notion de patrimoine en droit des régimes matrimoniaux et des successions." Lyon 3, 2008. https://scd-resnum.univ-lyon3.fr/in/theses/2008_in_bollon_n.pdf.
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L'étude du droit des régimes matrimoniaux et des successions conduit à remettre en cause la règle de l'unité du patrimoine. L'analyse du droit positif révèle de nombreuses brèches dans cette règle, brèches qui conduisent toutes à des masses patrimoniales autonomes. La remise en cause de la règle de l'unité n'est pas nouvelle. La rénovation nécessaire de la théorie du patrimoine passe par une redéfinition de la thèse des patrimoines d'affectation. Il ne s'agit pas de rejeter la personne hors du champ de la construction patrimoniale, mais de lui restituer une juste place et de fonder l'autonomie patrimoniale sur l'affectation des biens. L'association de l'actif et du passif ne peut constituer que la conséquence de l'affectation et non le critère du patrimoine. Cependant, l'affectation demeure une notion purement subjective qu'il faut rapprocher du droit de propriété. Ainsi, toutes les fois que l'affectation trouve un soutien dans le droit objectif de propriété, elle est la source d'une masse patrimoniale autonome. Cependant cette nouvelle approche de la théorie du patrimoine ne convient pas lorsque l'on a affaire à un patrimoine sur lequel plusieurs personnes peuvent prétendre exercer les mêmes prérogatives ; ce qui est le cas des biens communs sous le régime légal ou des biens indivis d'une succession. C'est la raison pour laquelle cette théorie des patrimoines d'affectation passe également par une redéfinition de la notion de propriété collective laquelle se résume à une pure concurrence de droits identiques sur un même bien<br>The study of the law of the matrimonial systems and the successions questions the rule of the unity of the heritage. The analysis of the substantive law reveals numerous breaches in this rule, breaches which lead all to autonomous patrimonial masses. The questioning of the rule of the unity is not new. The necessary renovation of the theory of the heritage passes by a redefining of the thesis of the "patrimoine d'affectation". It is not a question of rejecting the person outside the field of the patrimonial construction, but of restoring to her a just place and of basing the patrimonial autonomy on the affectation of the possessions. The association of the asset and the liabilities cannot constitute that the consequence of the affectation and not the criterion of the heritage. However, the affectation remains a purely subjective notion which it is necessary to move closer to the right of property. So, all the times as the affectation finds a support in the right objective of property, it is the source of an autonomous patrimonial mass. However this new approach of the theory of the heritage does not agree when we have to deal with a heritage on which several persons can claim to exercise the same privileges; what is the case of the common possessions under the legal system or the undivided possessions of a succession. It is the reason for which this theory of the affectation patrimonies also crosses by a redefining of the notion of collective property which arnounts to a pure competition of identical rights on the same good
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Triscott, Nicola. "Art and intervention in the stewardship of the planetary commons : towards a curatorial model of co-inquiry." Thesis, University of Westminster, 2017. https://westminsterresearch.westminster.ac.uk/item/q3677/art-and-intervention-in-the-stewardship-of-the-planetary-commons-towards-a-curatorial-model-of-co-inquiry.
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This Ph.D. by Published Work examines five projects that took place over ten years, between 2007 and 2016, that were curated as part of the artistic programme of Arts Catalyst,an independent interdisciplinary arts commissioning organisation of which the author is the founding director. This programme of work sought to understand what form of curatorial model and interpretative framework could generate new artworks and co-produce interdisciplinary knowledge across areas of specialist research and geopolitical urgency. The projects take the form of exhibitions, texts and edited books, which are presented as the portfolio of work. The selected projects are: Malamp UK, Brandon Ballengée (2007-2010); Arctic Perspective Initiative (2009-2011); ITACCUS – IAF Technical Activities Committee on the Cultural Utilisation of Space – and associated activities (2007-2014); Holoturian, Ariel Guzik (2013-2015); and Wrecked on the Intertidal Zone, YoHa, Critical Art Ensemble, et al. (2013-2016). Through analysis of and reflection on the projects, this commentary proposes a curatorial model of interdisciplinary co-inquiry, which can foster an ecology of practices, enabling curators, artists, scientists, specialist experts and people with situated expertise to coproduce knowledge around matters of concern, particularly relating to human environment interaction and common and extraterritorial spaces. It examines the roles of the curator in this model and how these might differ from those commonly understood as established curatorial practice. The commentary further presents an interpretative and tactical framework of the planetary commons for curating art-led projects in the realm of ecopolitical concerns, that can engage audiences and publics with the art and ideas emerging from this coinquiry approach. The combination of curatorial model and interpretative and tactical framework contribute to discourses on both inter/trans-disciplinarity and the role of art in relation to the politics of ecology. The Ph.D. contributes to the field on several levels. Within curatorial studies, the interdisciplinary co-inquiry model reconfigures curatorial practice as a collective, inquiry3 driven, knowledge-producing practice, and provides a useful methodology for inter- /trans-disciplinary artistic practice in relation to the politics of ecology, while the framework of the planetary commons proposes direction and allows for investment in reciprocity through commoning practices. Beyond contemporary art, a curatorial coinquiry model deepens and alters existing approaches for listening to, valuing, and synthesising different types of knowledge and expertise around current environmental and related social concerns. While the commentary argues for the planetary commons framework within the contemporary art space, there are wider implications for it as a complement and alternative to the dominant interpretative framework of the Anthropocene.
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Erfmeier, Alexandra. "Ursachen des Invasionserfolges von Rhododendron ponticum L. auf den Britischen Inseln Einfluss von Habitat und Genotyp /." Doctoral thesis, [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=975033476.
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Achour, Bilel. "Capteurs à ondes acoustiques de surface fonctionnant à 104 et 208 MHz. : modélisation, développement et application à la détection d’ions lourds métalliques." Thesis, Le Mans, 2020. http://www.theses.fr/2020LEMA1017.
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Les capteurs à ondes acoustiques de surfaces (SAW : Surface Acoustic Waves) présentent de nombreux avantages, dont une grande sensibilité, un paramètre clé dans diverses applications. Dans cette thèse, deux voies sont explorées pour améliorer la sensibilité des dispositifs SAWs : le passage en mode de Love, avec une couche guide d’onde en résine époxyde SU-8, et la montée en fréquence de 104 à 208 MHz. Avant de réaliser de tels dispositifs en salle blanche puis de les utiliser en tant que capteurs chimiques, des simulations numériques ont été entreprises, en utilisant tout d’abord le logiciel MATLAB, puis par la méthode des éléments finis, via le logiciel COMSOL Multiphysics. L’épaisseur optimale de la couche guide d’onde, permettant un gain important en sensibilité, a été estimée. Un écart entre l’expérience et la simulation a été trouvé soulignant la nécessité de poursuivre les phases d’optimisation dans cette voie. Une confrontation calculs/expériences a été menée avec succès pour les structures SH-SAW. Ces dispositifs ont été fonctionnalisés avec un dérivé d’anthracène pour détecter les ions zinc en milieu aqueux. Les résultats gravimétriques ont montré un gain en sensibilité d’un facteur 2.3, en augmentant la fréquence de travail de 104 MHz à 208 MHz<br>Surface Acoustic Wave (SAW) sensors have many advantages mainly a high sensitivity, which is a key parameter in various applications. Two strategies were explored, in this thesis, to enhance the sensitivity of SAW devices: switching to Love mode, with a waveguide layer in SU-8 epoxy resin, and frequency increase from 104 to 208 MHz. Prior to the realization of such devices in a clean room and their further use as chemical sensors, numerical simulations were done, first with MATLAB software, and then with the finite element method, via COMSOL Multiphysics software. The optimum thickness of the waveguide layer, allowing a significant gain in sensitivity, was estimated. A disagreement between experience and simulation was found highlighting the need to continue optimization steps. A confrontation between calculations / experiments was carried out for the SH-SAW structures. These devices were functionalized with an anthracene derivate for zinc ions detection in aqueous media. Gravimetric results indicate that increasing the operating frequency from 104 MHz to 208 MHz permits a gain in sensitivity by a factor of 2.3