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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.
181

Abstract Measure

Bridges, Robert Miller 08 1900 (has links)
This study of abstract measure covers classes of sets, measures and outer measures, extension of measures, and planer measure.
182

The White Stuff: Milking in the Outer Scottish Isles

Bond, Julie, Mulville, J., Craig, O.E. January 2005 (has links)
No
183

Measurable functions and Lebesgue integration

Brooks, Hannalie Helena 11 1900 (has links)
In this thesis we shall examine the role of measurerability in the theory of Lebesgue Integration. This shall be done in the context of the real line where we define the notion of an integral of a bounded real-valued function over a set of bounded outer measure without a prior assumption of measurability concerning the function and the domain of integration. / Mathematical Sciences / M. Sc. (Mathematics)
184

Caractérisation fonctionnelle de BamB, protéine impliquée dans la biogénèse de la membrane externe et la virulence de Salmonella / Functional caracterization of BamB, a protein involved in outer-membrane biogenesis and Salmonella virulence

Namdari, Fatémeh 26 March 2013 (has links)
La protéine BamB est une lipoprotéine de membrane externe appartenant au complexe BAM (β-Barrel Assembly Machinery) et impliquée dans l’assemblage des protéines de membrane externe (PME), la sensibilité aux antibiotiques, le contrôle de l’expression des trois systèmes de sécrétion de type III (T3SS) et la virulence de Salmonella. Chez E. coli, au sein du complexe BAM, elle interagit directement avec la protéine BamA. De plus, chez cette bactérie, BamB présente une activité sérine-thréonine kinase. Afin de mieux caractériser le rôle de BamB, nos objectifs ont été d’étudier (1) l’impact de l’altération de l’interaction de BamB avec le complexe BAM ou de sa séquestration dans le cytoplasme sur l’ensemble des rôles décrits de BamB et (2) l’activité kinase putative de BamB chez Salmonella. Nos résultats montrent que certains rôles de BamB sont dissociables entre eux et que l’interaction BamA/BamB n’est pas requise pour le rôle de BamB dans le contrôle de l’expression des T3SS, la virulence de Salmonella et l’assemblage des PME à la membrane externe. Aucune activité kinase ni aucune activité cytoplasmique de la protéine n’a pu être formellement démontrée. / BamB is an outer-membrane lipoprotein belonging to the BAM complex (β-Barrel Assembly Machinery). In Salmonella, it is involved in the assembly of outer membrane proteins (OMP), in antibiotic susceptibility, in the transcriptional control of the three Type-Three-Secretion-Systems (T3SS) related genes and also in virulence. In E. coli, BamB interacts directly with the BamA protein. Moreover, BamB has been shown to have a serine-threonin kinase activity in this bacterium. In order to better characterize the roles of the BamB protein, our purposes were to study (1) the impact of the alteration of the interaction of BamB with the BAM complex or of its cytoplasmic sequestration and (2) its putative kinase activity in Salmonella. Our results show that some of the BamB roles are dissociable and that the BamA/BamB interaction is not required for T3SS expression, Salmonella virulence or OMP assembly in the outer membrane. Currently, neither a kinase activity nor a cytoplasmic activity has been clearly demonstrated for this protein.
185

Measurable functions and Lebesgue integration

Brooks, Hannalie Helena 11 1900 (has links)
In this thesis we shall examine the role of measurerability in the theory of Lebesgue Integration. This shall be done in the context of the real line where we define the notion of an integral of a bounded real-valued function over a set of bounded outer measure without a prior assumption of measurability concerning the function and the domain of integration. / Mathematical Sciences / M. Sc. (Mathematics)
186

The importance of OuterMembrane Protein A in SerumResistance in Aggregatibacteractinomycetemcomitans serotype astrain D7SS

Dahlstrand Rudin, Arvid, Burstedt, John January 2017 (has links)
The Gram-negative bacterium Aggregatibacter actinomycetemcomitans is primarily associatedwith aggressive forms of periodontal disease. Additionally, it has occasionally been found to causemetastatic infections in non-oral sites. This requires the ability to evade the bactericidal activity ofthe complement system of the humoral immune system. Outer membrane proteins, namely,Omp100 and OmpA have been connected to normal human serum resistance for several bacteriaspecies. The objective of this study was to investigate if serum-resistant ompA mutants can beobtained, and to detect changes in OMP expression. We used A. actinomycetemcomitansserotype a strain D7SS and D7SS ompA knockouts. The strains were incubated in 50 % NHS.This resulted in a substantial decrease of survival among D7SS ompA knockouts. D7SS ompAknockouts were exposed to 50 % NHS once more to confirm stable serum resistance. 13 out of14 tested clones showed growth, indicating that serum resistant ompA mutants could begenerated. SDS-PAGE gel of extracted outer membrane vesicles revealed an additional proteinband of approximately 34 kDa in at least 4 of 5 tested serum resistant ompA mutants. This proteinband has been analyzed in the laboratory, and according to LC-MS/MS it contains an OmpAhomologue, which has been named OmpA2. We conclude that OmpA2 expression might be amajor mechanism for serum survival in A. actinomycetemcomitans serotype a strain D7SS ompAknockouts.
187

Teaching Standards or Standard Teaching? : An analysis of the Swedish national curriculum for English at upper-secondary school level

O'Neill, Ciarán January 2006 (has links)
<p>English is the most expansionist language in the world today. Currently, native speakers are outnumbered by non-native speakers by a ratio of 3:1, a ratio that is set to grow to 10:1 within the next ten years. One of the consequences of a language growing so rapidly is that its new users tend to ignore already accepted standards. In what linguists refer to as the outer and expanding circles of English-speakers (mainly in Africa and Asia) new varieties and standards of English are now being invented.</p><p>In this study, the effects of the current expansion of English on the teaching of English in Swedish upper-secondary schools are explored. Questions raised include: Should teachers of English in Sweden reflect the changing nature of English in their teaching? Should they readily adopt the New Englishes that are emerging or should they teach with the standard they have always used? The national curriculum for the teaching of English in Sweden is discussed in some detail. The guidelines therein are evaluated in terms of their ability to capture the changing face of English as well as their ability to give solid guidance to teachers in a classroom situation.</p><p>Findings derive from linguistic literature and from interviews conducted with English teachers at upper-secondary level. One of the main conclusions of the study is that whilst the national curriculum recognises the global diversity of English, its goals are overambitious in what it tries to achieve and thus it fails to provide teachers with practical guidance in their day-to-day teaching. A recommendation, therefore, is that the curriculum should be clearer in spelling out the importance of adhering to native standard varieties of English. However this does not mean that teachers should ignore the cultural diversity of the English-speaking world.</p>
188

Mimicking the Outer Coordination Sphere in [FeFe]-Hydrogenase Active Site Models : From Extended Ligand Design to Metal-Organic Frameworks

Pullen, Sonja January 2017 (has links)
Biomimetic catalysis is an important research field, as a better understanding of nature´s powerful toolbox for the conversion of molecules can lead to technological progress. [FeFe]-hydrogenases are very efficient catalysts for hydrogen production. These enzymes play a crucial role in the metabolism of green algae and certain cyanobacteria. Their active site consists of a diiron complex that is embedded in an interactive protein matrix. In this thesis, two pathways for mimicking the outer coordination sphere effects resulting from the protein matrix are explored. The first is the construction of model complexes containing phosphine ligands that are coordinated to the iron center as well as covalently linked to the bridging ligand of the complex. The effect of such linkers is an increased energy barrier for the rotation of the Fe(CO2)(PL3)-subunit, which potentially could stabilize a terminal hydride that is an important intermediate in the proton reduction cycle. The second pathway follows the incorporation of [FeFe]-hydrogenase active site model complexes into metal-organic frameworks (MOFs). Resulting MOF-catalysts exhibit increased photocatalytic activity compared to homogenous references due to a stabilizing effect on catalytic intermediates by the surrounding framework. Catalyst accessibility within the MOF and the influence of the framework on chemical reactivity are examined in the work presented. Furthermore, an initial step towards application of MOF-catalysts in a device was made by interfacing them with electrodes. The work of this thesis highlights strategies for the improvement of biomimetic model catalysts and the knowledge gained can be transferred to other systems mimicking the function of enzymes.
189

Untersuchung von humanen Melanozyten aus der äußeren Haarwurzelscheide des Haarfollikels auf unterschiedlichen biokompatiblen Scaffolds als neuer Ansatz in der Vitiligotherapie

Sülflow, Katharina 14 November 2016 (has links) (PDF)
Um eine verbesserte Therapieoption mit weniger Schmerzen und Nebenwirkun-gen für Patienten mit Depigmentierungsstörungen wie Vitiligo zu entwickeln, wurde eine Methode zur nichtinvasiven Gewinnung von autologen Melanozyten aus der Haarwurzel genutzt. Die Haarwurzel als einfach zugängliches Stammzell-reservoir bietet die Möglichkeit, Vorläufermelanozyten aus der äußeren Haar-wurzelscheide zu isolieren, differenzieren und zu proliferieren. Für zukünftige autologe Transplantationsversuche wurden in dieser Arbeit die kultivierten hu-manen Melanozyten aus der äußeren Haarwurzelscheide (Human Melanocytes from the Outer Root Sheath, HUMORS) auf drei unterschiedlichen Scaffolds getes-tet. Hinsichtlich mitochondrialer Aktivität (Marker für Zellproliferation), mela-nozytenspezifischer Markerexpression und ihrer Funktionalität (Tyrosinase-Enzymaktivität und Melaningehalt) wurden die Zellen auf Collagen Cell Carrier® (CCC), Poly-ε-Caprolacton-Scaffolds (PCL) und kollagen basierten Hydrogelen (cGEL) kultiviert und charakterisiert. Alle Scaffolds waren biokompatibel, immu-nologisch nur gering aktiv und wiesen eine dreidimensionale Struktur auf, die der extrazellulären Matrix nachempfunden war. Einen positiven Effekt auf die Prolife-ration wiesen die HUMORS auf den Collagen Cell Carrier® auf. Bei Untersuchun-gen der melanotischen Aktivität überzeugten die HUMORS auf dem cGEL Typ4 durch einen signifikant höheren Melaningehalt. Da Melanin das entscheidende Produkt der Repigmentierung bei Vitiligoläsionen ist, stellte sich damit das cGEL Typ4 als vielversprechender Zellträger für die Kultivierung und vorgesehene Transplantation der Melanozyten heraus.
190

Investigation of Anaplasma phagocytophilum and Anaplasma marginale adhesin-host cell interactions

Hebert, Kathryn S. 01 January 2016 (has links)
Anaplasma phagocytophilum and A. marginale are the etiologic agents of bovine anaplasmosis and human granulocytic anaplasmosis, respectively. As obligate intracellular pathogens, binding and entry of host cells is a prerequisite for survival. The molecular events associated with these processes are poorly understood. Identifying the adhesins mediating binding, delineating their key functional domains, and determining the molecular determinants to which they bind not only benefits better understanding of Anaplasma spp. pathobiology, but could also benefit the development of novel approaches for protecting against infection. We previously demonstrated that A. phagocytophilum outer membrane protein A (ApOmpA) is critical for bacterial binding and entry host through recognition of α2,3-sialic acid and α1,3-fucose of its receptors, including 6-sulfo-sLex. In this study, we determined that two amino acids, G61 and K64, within its binding domain (ApOmpA59-74), are essential for ApOmpA function. We also confirmed the ability of ApOmpA to act as an adhesin and invasin as it conferred adhesiveness and invasiveness to inert beads. We next extended our studies to A. marginale as it also expresses OmpA (AmOmpA) and its role in infection has not been studied. Molecular models of ApOmpA and AmOmpA were nearly identical, especially in the ApOmpA binding domain and its counterpart in AmOmpA. Antisera raised against AmOmpA or its putative binding domain inhibit A. marginale infection. AmOmpA G55 and K58 are contributory and K59 is essential for AmOmpA to bind to host cells. AmOmpA binding is dependent on α2,3-sialic acid and α1,3-fucose. Coating inert beads with AmOmpA conferred the ability to bind to and be taken up by host cells, confirming that it acts as an adhesin and invasin. 6-sulfo-sLex is dispensable for AmOmpA binding and A. marginale infection. ApOmpA works cooperatively with Asp14 (14-kDa A. phagocytophilum surface protein) to promote optimal infection of host cells. We found that Asp14 is conserved across A. phagocytophilum strains and in A. marginale and confirmed the ability of Asp14 to act as an adhesin and invasin as it conferred adhesiveness and invasiveness to inert beads. Collectively, this work advances our understanding of A. phagocytophilum and A. marginale adhesion and invasion of host cells.

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