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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Synthèses de carbocycles et d'hétérocycles à cinq chaînons par activation de liaisons c(sp3)-h non activées / Intramolecular Palladium-Catalyzed C(sp3)-H Arylation of aryl and alkenyl halides : synthesis of fused five-membered rings

Sofack-Kreutzer, Julien 16 December 2011 (has links)
La fonctionnalisation de liaisons C-H réputées peu réactives ouvre de nouvelles perspectives en synthèse organique. La catalyse par un métal de transition comme le palladium représente une solution particulièrement efficace à ce problème. Les travaux de thèse présentés dans ce mémoire s’inscrivent dans ce contexte. Dans un premier temps, la réaction étudiée, catalysée par le palladium, a visé à étendre une méthodologie mise au point au laboratoire pour la synthèse de carbocycles et d’hétérocycles à cinq chaînons par activation intramoléculaire de liaisons C(sp3)-H à partir de chlorures d’aryles. Ces derniers sont en effet plus disponibles et moins onéreux que les bromures d’aryle correspondants. Des études d’optimisation ont été effectuées pour la mise au point d'une réaction diastéréosélective et régiosélective. Plusieurs substrats ont été synthétisés pour être ensuite placés dans les conditions optimales de la réaction d’activation C(sp3)-H, et ont conduit à une grande diversité de cycles à cinq chaînons fusionnés. Dans un deuxième temps, nos travaux ont consisté à étendre l’activation C(sp3)-H pallado-catalysée à des précurseurs non aromatiques cycliques ou acycliques. Pour des raisons d'accessibilité, nos études se sont alors portées sur la préparation de bromures vinyliques azotés pouvant conduire après activation C-H à des motifs hexahydroindoles ou pyrrolidines. De nouvelles conditions d’activation CH ont alors été trouvées pour cette famille de substrats, et ont conduit aux hétérocycles cibles de manière diastéréosélective et régiosélective. Après extension de la réaction à divers précurseurs, nous nous sommes intéressés à la synthèse d’un intermédiaire poly-fonctionnalisé permettant d'accéder aux aéruginosines, famille de produits naturels bioactifs. / The direct functionalization of unactivated C-H bonds represents an atom- and step-economical alternative to more traditional synthetic methods based on functional group transformation, which often require multi-step sequences. In particular, transition-metal catalysis has recently emerged as a owerful tool to functionalize otherwise unreactive C-H bonds. In this context, we first investigated the extension of a methodology that has been developed in our laboratory for the synthesis of fused five-membered rings via palladium-catalyzed C(sp3)-H activation from aryl chlorides. Optimization studies were conducted and reaction conditions leading to a regioand diastereoselective process were found. These optimal conditions were applied to various ubstrates, giving rise to a variety of fused five-membered carbocycles and heterocycles. Next, our work was devoted to the extension of the palladium-catalyzed C(sp3)-H activation to cyclic and acyclic non aromatic precursors. Our studies focused on the preparation of the more accessible nitrogen-containing bromoalkene substrates, leading to interesting hexahydroindole or pyrrolidine motifs by C-H activation. New C-H activation conditions were adapted to this family of substrates and led to the synthesis of the target heterocycles in a regio- and diastereoselective manner. As a more complex application of this method, we investigated the synthesis of a polyfunctionalized intermediate allowing the access to the aeruginosin family of bioactive natural products.
432

Synthèses de molécules polycycliques par arylation C(sp³)-H intramoléculaire catalysée par le palladium / synthesis of polycyclic molecules by intramolecular palladium-catalyzed C(sp³)-H arylation

Pierre, Cathleen 16 October 2012 (has links)
La synthèse de produits complexes se doit de prendre en compte de nouvelles méthodes desynthèse plus efficaces, dont la fonctionnalisation de liaisons carbone-hydrogène. Dans cecontexte, la catalyse homogène par les métaux de transition s’est avérée performante, tout encontrôlant la régio- et la chimiosélectivité de la réaction. Les travaux de thèse présentés dansce manuscrit témoignent de l’efficacité de cette stratégie pour la construction rapide decomplexité moléculaire.Dans un premier temps, nous nous sommes intéressés à l’utilisation de précurseurs chlorés, cequi a permis d’étendre significativement le champ d’application de l’arylation C(sp3)-Hintramoléculaire pallado-catalysée. Ces travaux ont conduit à la synthèse de nombreuxhétérocycles, difficilement accessibles par d’autres voies de synthèse plus traditionnelles.Dans un deuxième temps, le développement d’une méthodologie de double arylation C-Hnous a permis de synthétiser des molécules polycycliques aux squelettes originaux. Une seuleet même espèce catalytique permet dans ce cas de réaliser les deux opérations d’activation CHavec succès.Par la suite, nous avons montré qu’il était possible de synthétiser des composés énantioenrichispar arylation C(sp3)-H intramoléculaire asymétrique. Pour cela, les ligands chiraux detype phosphépine se sont avérés particulièrement performants, et induisent desénantiosélectivités prometteuses.Enfin, notre attention s’est portée vers la synthèse de polycycles par arylation C(sp3)-Hintramoléculaire deshydrogénante. Les résultats encourageants obtenus apparaissent commeune preuve de concept dans ce domaine, où très peu de travaux de recherche ont été rapportés. / The direct functionalization of C-H bonds constitutes a faster and more « atom-economical »synthetic approach. This concept is gradually modifying organic chemistry, because itprovides chemists of both academic and industrial worlds with new disconnection strategies,giving access to molecules of original structures and properties in a more efficient andecological manner.In this context, we first investigated the extension of the intramolecular palladium-catalyzedC(sp3)-H arylation, by using aryl chlorides as coupling partners. This methodology wasapplied to the synthesis of fused valuable five-membered carbocycles and heterocycles.A further part of this work focused on the synthesis of polycyclic molecules by double C-Harylations. Interestingly, a single batch of catalyst was able to perform both operations in onepot, which indicates that this concept can be used for the rapid construction of molecularcomplexity.Then, we focused our efforts on the enantioselective synthesis of indanes and heterocyclicanalogues by intramolecular C(sp3)-H arylation. The employment of a chiral binepine ligandplays a key role in this palladium-catalyzed process to achieve moderate to highstereoinduction.Finally, our work was devoted to the construction of fused thiophenes by intramolecular PdIIcatalyzeddeshydrogenative C(sp3)–H arylation.
433

Measuring the health burden of hepatitis C at an individual and population level in Australia

Thein, Hla-Hla, Public Health & Community Medicine, Faculty of Medicine, UNSW January 2006 (has links)
This thesis examines the effect of hepatitis C virus infection (HCV) on health-related quality of life (HRQOL) to define burden of disease at individual and population levels. A systematic review of HCV HRQOL studies was undertaken with translation of Short Form-36 (SF-36) Health Survey data into community-weighted health state utilities using three different methods. Derived estimates of health utilities were 0.87 for HCV treatment-induced sustained virological response (SVR); 0.81 for pre-cirrhosis; 0.76 for compensated cirrhosis; 0.69 for decompensated cirrhosis; 0.67 for hepatocellular carcinoma (HCC); and 0.77 for liver transplant. The HCV health state utilities varied considerably from expert estimates, with relatively lower estimates for early liver disease and higher estimates for advanced liver disease, but were comparable to direct patient-elicited utilities. A study utilising data from population-based health surveys incorporating HCV screening among prisoners at Australian correctional centres in 1996 and 2001 showed no measurable effect of HCV on HRQOL, including that attributable to HCV viraemia. Compared to uninfected Australian norms, prisoners had lower HRQOL irrespective of HCV status. Several non-HCV factors such as age, co-morbidity, severity of depressive symptoms, and medical care utilization influenced HRQOL. A prospective study of health outcomes among HCV monoinfected and HIV/HCV coinfected individuals conducted at Sydney tertiary level hepatitis clinics between 2003 and 2005 found similar cognitive function, mood, and HRQOL patterns in these two HCV groups in the context of pegylated interferon (PEG-IFN) alfa-2a and ribavirin therapy. The HCV groups had similar levels of pre-treatment HRQOL impairment, further on-treatment deterioration, and posttreatment improvements. SVR was associated with significant HRQOL improvements, but mental HRQOL improvement was also seen in individuals not achieving an SVR. The impact of HCV treatment uptake on HCV-related burden of disease at a population level in Australia was examined using a mathematical model. The model estimated that in 2004, there were ~181,500 cases of chronic HCV infection, 7,020 with HCV-related cirrhosis, and annual incidence of 238 cases of HCV-related liver failure and 70 cases of HCV-related HCC. Compared to no treatment, current treatment levels (~1% of HCV-infected individuals per annum) would reduce projected HCV-related cirrhosis and advanced liver disease numbers by ~30% at 2020 and a gain of ~122,200 Quality-Adjusted Life Years (QALYs). Even with a five-fold increase from current treatment levels, advanced liver disease numbers will continue to increase through 2020 but will be reduced by ~55% and a gain of ~483,200 QALYs.
434

Wavelets and C*-algebras

Wood, Peter John, drwoood@gmail.com January 2003 (has links)
A wavelet is a function which is used to construct a specific type of orthonormal basis. We are interested in using C*-algebras and Hilbert C*-modules to study wavelets. A Hilbert C*-module is a generalisation of a Hilbert space for which the inner product takes its values in a C*-algebra instead of the complex numbers. We study wavelets in an arbitrary Hilbert space and construct some Hilbert C*-modules over a group C*-algebra which will be used to study the properties of wavelets. We study wavelets by constructing Hilbert C*-modules over C*-algebras generated by groups of translations. We shall examine how this construction works in both the Fourier and non-Fourier domains. We also make use of Hilbert C*-modules over the space of essentially bounded functions on tori. We shall use the Hilbert C*-modules mentioned above to study wavelet and scaling filters, the fast wavelet transform, and the cascade algorithm. We shall furthermore use Hilbert C*-modules over matrix C*-algebras to study multiwavelets.
435

IQ-mower : simulering av positionsbestämning i programspråket C++

Hultén, Monica, Gottfridsson, Gunilla January 2003 (has links)
No description available.
436

Implementation av timingbaserat fightingspel till Kinect i C# och WPF / Implementation of a timing-based fighting game for Kinect in C# and WPF

Lindström, Alexander, Ringensjö, Emil January 2013 (has links)
Spelutveckling är något som ständigt förändras, möjligheterna vi har idag är väldigt olika de möjligheter vi hade för tio år sedan och de möjligheter som vi kommer att ha om tio år. I denna rapport vill vi utforska några av dessa nya möjligheter och vi vill därför ta reda på hur väl lämpat C# och WPF är för implementationen av ett timingbaserat fightingspel till rörelsesensorn Microsoft Kinect genom att genomföra sagda implementation. Resultatet av detta examensarbete är en tidig version av spelet och en analys av de svårigheter som har uppstått och de begräsningar som vi har upptäckt med C#, WPF och Kinect.
437

IQ-mower : simulering av positionsbestämning i programspråket C++

Hultén, Monica, Gottfridsson, Gunilla January 2003 (has links)
No description available.
438

Giving Meaning to Macros

Mennie, Christopher January 2004 (has links)
With the prevalence of legacy C/C++ code, issues of readability and maintainability have become increasingly important. When we consider the problem of refactoring or migrating C/C++ code, we see the significant role that preprocessor directives play. It is partially because of these preprocessor directives that code maintenance has become extremely difficult. This thesis describes a method of fact extraction and code manipulation to create a set of transformations which will remove preprocessor directives from the original source, converting them into regular C/C++ code with as few changes as possible, while maintaining readability in the code. In addition, some of the subtle issues that may arise when migrating preprocessor directives are explored. After discussing the general architecture of the test implementation, an examination of some metrics gathered by running it on two software systems is given.
439

ACTH Increases Expression of c-fos, c-jun and β-actin Genes in the Dexamethasone-treated Rat Adrenals

MATSUI, NOBUO, TAKAGI, HIROSHI, FUNAHASHI, HIROOMI, SATOH, YASUYUKI, MIYAMOTO, NORIHIRO, MURATA, YOSHIHARU, IMAI, TSUNEO, SEO, HISAO, OHNO, MOTOTSUGU 08 1900 (has links)
名古屋大学博士学位論文 学位の種類 : 医学博士(論文) 学位授与年月日:平成4年9月22日 大野元嗣氏の博士論文として提出された
440

Virtues, pluralism, and human nature : prospects for an integration of virtue ethics and modern moral theory /

Rouintree, Kevin Paul, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 396-400). Available also in a digital version from Dissertation Abstracts.

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