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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.
101

Association of killer immunoglobulin-like receptor (KIR) genes with tuberculosis disease in two Canadian cohorts

Braun, Kali 07 1900 (has links)
In Canada, and more specifically in Canadian-born Aboriginals and foreign born populations, high incidence of tuberculosis (TB) causes significant morbidity and mortality. The presence or absence of specific killer immunoglobulin-like receptor (KIR) genes, individually or in conjunction, may be associated with tuberculosis (active, latent, or uninfected disease status) as well as ethnicity of an individual. It is hypothesized that the differences in KIR profiles, gene frequencies, and/or haplotypes in Canadian-born Aboriginal, Canadian-born non-Aboriginal, and foreign born individuals elicits a differential activation or inhibition profile, resulting in differential cytokine expression and eventually contributes to the outcome of TB infection. In this study we examined the enrichment or depletion of KIR genes in different ethnic populations in Manitoba with special focus on active, latent, and uninfected TB status. In addition, we sought to explore the statistical correlation between TB status and inhibitory/stimulatory KIR haplotypes.
102

Beyond The Hills

Cates, Joel 14 September 2009 (has links)
A couple travels through Spain in order to obtain an abortion for an unwanted pregnancy. The couple, an unnamed American man and a woman known only by the nickname Jig, has a much more complicated relationship than first seems and must navigate through complex emotions and gender roles. This story, and elaboration on Hemingway’s well known “Hills Like White Elephants”, attempts to give the characters introduced by Hemingway more depth and back story than the original short story.
103

TL dating and geochemistry of brickearths in S.E. England

Parks, D. A. January 1989 (has links)
No description available.
104

Studies of nucleation and growth of hard carbon coatings using energy-assisted chemical vapour deposition processes

Ali, Nasar January 2001 (has links)
No description available.
105

Infinite graphs, graph-like spaces and B-matroids

Christian, Robin January 2010 (has links)
The central theme of this thesis is to prove results about infinite mathematical objects by studying the behaviour of their finite substructures. In particular, we study B-matroids, which are an infinite generalization of matroids introduced by Higgs \cite{higgs}, and graph-like spaces, which are topological spaces resembling graphs, introduced by Thomassen and Vella \cite{thomassenvella}. Recall that the circuit matroid of a finite graph is a matroid defined on the edges of the graph, with a set of edges being independent if it contains no circuit. It turns out that graph-like continua and infinite graphs both have circuit B-matroids. The first main result of this thesis is a generalization of Whitney's Theorem that a graph has an abstract dual if and only if it is planar. We show that an infinite graph has an abstract dual (which is a graph-like continuum) if and only if it is planar, and also that a graph-like continuum has an abstract dual (which is an infinite graph) if and only if it is planar. This generalizes theorems of Thomassen (\cite{thomassendual}) and Bruhn and Diestel (\cite{bruhndiestel}). The difficult part of the proof is extending Tutte's characterization of graphic matroids (\cite{tutte2}) to finitary or co-finitary B-matroids. In order to prove this characterization, we introduce a technique for obtaining these B-matroids as the limit of a sequence of finite minors. In \cite{tutte}, Tutte proved important theorems about the peripheral (induced and non-separating) circuits of a $3$-connected graph. He showed that for any two edges of a $3$-connected graph there is a peripheral circuit containing one but not the other, and that the peripheral circuits of a $3$-connected graph generate its cycle space. These theorems were generalized to $3$-connected binary matroids by Bixby and Cunningham (\cite{bixbycunningham}). We generalize both of these theorems to $3$-connected binary co-finitary B-matroids. Richter, Rooney and Thomassen \cite{richterrooneythomassen} showed that a locally connected, compact metric space has an embedding in the sphere unless it contains a subspace homeomorphic to $K_5$ or $K_{3,3}$, or one of a small number of other obstructions. We are able to extend this result to an arbitrary surface $\Sigma$; a locally connected, compact metric space embeds in $\Sigma$ unless it contains a subspace homeomorphic to a finite graph which does not embed in $\Sigma$, or one of a small number of other obstructions.
106

Synthesis and Characterization of Diamond-like Carbon Thin Films for Biomedical Applications

Leonard, Russell Lee 01 December 2010 (has links)
Diamond-like carbon (DLC) thin films were produced by pulsed laser deposition (PLD) on silicon, fused silica, and silicon nitride substrates. The films produced were either undoped, made using a pure graphite target, or doped, using multi-component targets made from a combination of graphite and silicon, silicon nitride, titanium dioxide, or silicon monoxide. These films were evaluated for their potential use in biomedical applications, including coatings for artificial joints, heart stents, and bronchoscopes. The films were characterized by Raman spectroscopy, atomic force microscopy, ball-on-flat tribometry, contact angle measurements, and spectrophotometry. Film thickness was determined by optical profilometry. Film adhesion was checked by soaking the films in simulated body fluid (SBF) and monitoring the quality of the film surface at varying time intervals using an optical microscope. DLC coatings were produced with a root mean square surface roughness of less than 1 nm and a 0.08 lubricated coefficient of friction. Contact angles of water on the undoped films varied with deposition conditions, ranging from 65 to 88 degrees. Contact angles as low as 25 degrees were achieved by incorporating silicon monoxide dopant. DLC coatings were produced on fused silica having high transparency and showing no delamination after forty-three weeks of immersion in SBF. These results indicate that these films have potential as biomedical coatings.
107

Fabrication and properties of diamond-like carbon films in discharge plasmas

Rybachuk, Maksym January 2007 (has links)
This thesis presents theoretical and experimental study of properties of amorphous diamond-like carbon (DLC) coatings synthesised using discharge plasma methods. There were two objectives in this study. The first objective was to investigate the formation mechanism of hydrogenated DLC films (a-C:H) in an open hydrocarbon plasma source. The inductively coupled plasma (ICP) reactor was used to synthesise the films and the formation of sp2 and sp3 hybridised phases and the combination of these phases in the ICP plasma environment was studied. It was found that for a-C:H films with narrow distribution of the sp3 content the mechanical properties are determined by the degree of disorder of the sp2 fraction. The relationship between the sp3 content in fabricated films and hardness and Young's modulus was established. Raman and multi-wavelength (Vis – UV range) Raman spectroscopy was primarily used together with other suitable analytical methods to examine a-C:H films and it was found that films fabricated at higher ion energies displayed higher degree of clustering and bonding disorder than films produced at lower ion energies. All as fabricated a-C:H films were also found contain basic π-conjugated polymer inclusions as of trans-polyacetylene. The Raman results also reveal that the magnitude of Rayleigh scattered light is related to the relative density of the films, a feature that can be useful for monitoring film growth in-situ. The use of X-ray photoelectron spectroscopy (XPS) as a suitable method for measuring the sp3 content of the bulk DLC was also established. The second objective was to develop a fabrication technique that would allow fabrication of DLC films using graphite target sputtering with a single focused ion beam source and producing films with medium-high sp3 content. This research was motivated by the industrial partner of the project Laserdyne Pty Ltd that required a simple DLC deposition apparatus to be integrated into a standard, stand alone, optical thin film deposition chamber. Such technique was developed on the basis of a conventional ion beam target sputtering. In our experiments hydrogen-free DLC films with medium sp3 content were produced using a single, Kaufmann type ion source operated at low energies. The fabrication technique, denoted a reactive ion beam sputter deposition (RIBSD), was based on sputtering a graphite target at low incident angles and positioning the substrate at the grazing angles to the incoming ions, thus the incident ions (Ar and Xe ions were used) were simultaneously bombarding the target and the growing film. The effect of angle of incidence of an ion beam to the target and to the substrate in creating the sp3 content in DLC was investigated. It was found that the infringement bombardment of the substrate was not favourable for DLC growth as it essentially provided for a secondary re-sputtering process. Quality DLC films with approximately 40 % of the sp3 content were fabricated at the optimal angle of the ion flux to the target of 30º and to the substrate of 0º (parallel to the ion bema axis). The increased ion energy contributed to structural changes in DLC from predominantly sp2 graphitic like bonding to tetrahedral sp3 bonding arrangement.
108

Studies of complexes formed in blood in vivo between an insulin-like growth factor analog and binding proteins / by Oraprapai Gajanandana.

Gajanandana, Oraprapai January 1997 (has links)
Includes bibliographical references (43 leaves) / xxiii, [216] leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study shows that when LR3IGF-I is administered to animals in pharmacologically active doses, it may be present in either the free form or bound to IGF-binding protein(s) in the circulation. Age and nutrition which are factors that regulate synthesis of endogenous IGF-I and IGF-binding proteins, affect the in vivo formation of complexes between the analog and IGFBP(s). This study also suggests that IGFBP-1 inhibits the pharmacological activity of circulating LR3IGF-I on thymus whereas it appears to stimulate the pharmacological activity of LR3IGF-I in kidneys. / Thesis (Ph.D.)--University of Adelaide, Dept. of Biochemistry, 1998?
109

Studies to identify and characterise IGF-binding determinants of IGFBP-2 / by Graham D. Hobba.

Hobba, Graham D. (Graham Dean) January 1999 (has links)
Copies of author's previously published articles inserted behind back end-papers. / Bibliography: leaves 139-160. / 160 leaves : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Identifies and characterises specific residues of biGFBP-2 that comprises the IGF binding site. / Thesis (Ph.D.)--University of Adelaide, Dept. of Biochemistry, 1999
110

Insulin-like growth factor II : cellular effects through different receptors /

Zhang, Qimin, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.

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