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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.
211

No pity distilled : Britain and the Chetniks, 1941-1942

Trew, Simon January 1991 (has links)
Chapter IV examines the increasing level of British interest in the Yugoslav revolt. Inadequately informed, and under pressure from internal and external sources, the British government resolved during autumn 1941 to offer exclusive support to Mihailovic. This decision was taken despite the knowledge that fighting had broken out between the insurgent groups. Chapter V covers the first part of 1942. Despite a growing awareness of the Partisan contribution to the anti-Axis struggle, and of the existence of civil war within Yugoslavia, the British continued to offer their full moral support to Mihailovic, and to attempt to rally all Yugoslavs to him. Chapter VI shows how during the second half of 1942, due to growing doubts over Mihailovic's political objectives and military strategy, the British policy consensus gradually disintegrated. Consequently, the reaffirmation of British support for Mihailovic at the end of the year was little more than a facade. Finally, the conclusion illustrates how British expectations of Mihailovic were based on a fundamental misevaluation not only of the latter's capabilities, but also of the very nature of the Yugoslav resistance movements.
212

Video compression techniques and rate-distortion optimisation

Handcock, Jason Anthony January 2000 (has links)
No description available.
213

Studies towards the total synthesis of strychnine

McGowan, Amanda Dawn January 2000 (has links)
No description available.
214

Expression and function of multidrug resistance-associated proteins (MRP) in human intestine

Prime-Chapman, Hannah Margaret January 2002 (has links)
No description available.
215

An investigation of the role of mitochondria in the cardioprotective action of calcium agonists

Baydoun, A. R. January 1988 (has links)
No description available.
216

Assessing Memory in an Aldehyde Dehydrogenase 2 Knockout Model of Alzheimer's Disease

Elharram, AHMED 28 September 2013 (has links)
The study of Alzheimer’s Disease (AD) has been hindered by the absence of animal models of late-onset/age-related AD (also termed sporadic AD) (95% of AD cases) since current transgenic mouse models exhibit pathological changes dependent on overexpression of mutant human genes linked to early-onset, familial AD (5% of cases). Oxidative stress is considered to be a causative factor in age-related AD, and we have found that aldehyde dehydrogenase 2 (Aldh2) null mice exhibit not only oxidative stress, but also display many AD-like pathologies. The current study used behavioral analysis to assess whether Aldh2-/- mice also exhibit memory and cognition deficits. Male and female wild type and Aldh2-/- mice were tested monthly beginning at three months of age, using the open field novel object recognition test (a measure of recognition memory), as well as spontaneous alternations in the Y-maze (a measure of spatial working memory). In both tasks, significant decreases in performance occurred in Aldh2-/- mice by 3.5-4 months of age, and this progressively declined over the next three months compared to wild type mice. Sex-related differences in memory impairment were not observed. These results, together with the findings that AD-like pathologies are also present, suggest that Aldh2-/- mice represent a new, oxidative stress-based model of age-related cognitive impairment and AD. This model may prove useful both for assessing AD therapeutics and for gaining better insight into the pathogenesis of AD. / Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2013-09-26 11:20:00.023
217

Dietary prevention of type 2 diabetes : the role of fruit and vegetable intake

Carter, Patrice January 2012 (has links)
This thesis begins with a background chapter which explores the current diabetes epidemic and examines the role of obesity and oxidative stress as causative factors. Current dietary recommendations for prevention of type 2 diabetes are critically evaluated. A systematic review and meta-analysis was conducted to determine the independent role of fruit and vegetables in preventing diabetes. Convincing benefit for greater consumption of green leafy vegetables was demonstrated. An insignificant trend towards benefit was observed for fruit and vegetables. The Fruit and Vegetable Intake and Glucose Control Study (FIVE) is a sub study of the Let’s Prevent Diabetes Study. FIVE includes cross sectional analysis of baseline plasma vitamin C, (a biomarker for fruit and vegetable intake) from 2101 participants. FIVE further includes 12 months analysis of individuals with impaired glucose regulation, randomised to receive group education or usual care. Results demonstrate 29% of the population consumed at least 5 portions of fruit and vegetables a day. Fewer South Asian individuals met the recommendation compared to White Europeans (21% vs. 30% p = 0.003). Each additional piece of fruit or vegetable consumed (21.8μmol/l plasma vitamin C) was associated with a reduction of 0.04% in HbA1c, 0.05mmol/l in fasting and 0.22mol/l in 2 hour blood glucose. Participants who consumed 5 portions a day compared to those who did not, had a 24% associated reduced risk of being diagnosed with impaired glucose regulation (OR = 0.76, 95% CI: 0.59 to 0.98). At 12 months follow up those receiving lifestyle education had greater levels of plasma vitamin C compared to those in the usual care arm (36.1μmol/l (SD 20.7) vs.29.9μmol/l (SD 20.3)). No statistical difference in mean change between intervention arms was seen. The thesis provides novel, robust nutritional biomarker data from a large at risk, multi ethnic population. Results support recommendations to promote fruit and vegetables in the diet to prevent diabetes. The potential for tailored advice on increasing green leafy vegetables among those at risk of diabetes should be investigated further.
218

Lineage II of Southeast Asian/American DENV-2 is Associated with a Severe Dengue Outbreak in the Peruvian Amazon

Williams, M., Mayer, S. V., Johnson, W. L., Chen, R., Volkova, E., Vilcarromero, S., Widen, S. G., Wood, T. G., Suarez Ognio, L., Long, K. C., Hanley, K. A., Morrison, A. C., Vasilakis, N., Halsey, E. S. 07 July 2014 (has links)
During 2010 and 2011, the Loreto region of Peru experienced a dengue outbreak of unprecedented magnitude and severity for the region. This outbreak coincided with the reappearance of dengue virus-2 (DENV-2) in Loreto after almost 8 years. Whole-genome sequence indicated that DENV-2 from the outbreak belonged to lineage II of the southeast Asian/American genotype and was most closely related to viruses circulating in Brazil during 2007 and 2008, whereas DENV-2 previously circulating in Loreto grouped with lineage I (DENV-2 strains circulating in South America since 1990). One amino acid substitution (NS5 A811V) in the 2010 and 2011 isolates resulted from positive selection. However, the 2010 and 2011 DENV-2 did not replicate to higher titers in monocyte-derived dendritic cells and did not infect or disseminate in a higher proportion of Aedes aegypti than DENV-2 isolates previously circulating in Loreto. These results suggest that factors other than enhanced viral replication played a role in the severity of this outbreak.
219

Interaction aube-carter : contribution de l’usure de l’abradable et de la thermomécanique sur la dynamique d’aube / Blade-casing interaction : contribution of the abradable wear and the thermomechanical behavior on the blade dynamics

Millecamps, Antoine 10 September 2010 (has links)
L’enjeu actuel pour les fabricants de turboréacteurs est de fournir des moteurs peu polluants tout en assurant un rendement élevé. Une solution consiste en une réduction significative du jeu entre le rotor aubagé et le stator. Toutefois, le fonctionnement à jeu très faible induit inévitablement des contacts pouvant engendrer des pertes d’aubes. De nombreuses études identifiant les phénomènes vibratoires se sont révélées insuffisantes pour appréhender le problème de contact rotor-stator. Afin de franchir un cap dans la compréhension du contact, ces travaux de thèse proposent de considérer l’influence des phénomènes se produisant lors d’un contact frottant aube-carter : l’usure et le comportement thermomécanique.D’abord des résultats d’essais de contact aube-carter sur un banc à échelle réelle sont analysés permettant d’observer clairement l’usure du carter et les échauffements à l’échelle locale du contact.Afin d’expliquer ces observations expérimentales, des simulations numériques sont réalisées. Les études de la dynamique d’aube apportent une explication sur les profils d’usure du carter. Des simulations thermomécaniques montrent une influence significative des dilatations thermiques au contact.Enfin, une étude numérique couplée d’une aube en contact avec un carter est menée, considérant l’usure du carter induite par la dynamique de l’aube en contact, les échauffements et les dilatations thermiques se produisant au contact aube-carter. L’influence de ces phénomènes sur la dynamique de l’aube est clairement démontrée notamment les variations de régime vibratoire et les conditions pouvant entrainer la divergence du système. / The issue for the turbojet engine designers is to make less polluting et more efficient engine. A solution is to reduce significantly the clearance between the rotating bladed disk and the casing. However, operating with a very tight clearance induces inevitably interactions which can lead to loses of blades. Many studies identifying the vibratory phenomena are appeared as insufficient to totally understand the problem of contact. To reach a milestone this work proposes the study of the influence of the local phenomena during a blade-casing rubbing contact: wear and thermomechanical behavior.At first, the results of a study of a blade-casing contact performed on an experimental compressor of a turbojet at a real scale are analyzed in order to clearly identify the wear of the casing and the heating at the contact.Numerical simulations are preformed to explain these experimental observations. A study of the blade dynamics can explain the wear pattern of the casing. Thermomechanical simulations highlight a significant influence of thermal expansions on the contact.A numerical study of the dynamics of a blade interacting with a casing is performed with the consideration of the wear induced by the contact and the heatings and thermal expansions occurring at the local contact. It clearly highlights the influence of these phenomena on the blade dynamics, notably the variations of vibratory behavior and the conditions which can lead to the divergence of the system.
220

Evaluación del estado metabólico y presencia de lavaduras del género Candida en pacientes con diabetes mellitus tipo 2

González Saldaña, Jaime Martín January 2014 (has links)
Trabajo de Investigación Requisito para optar al Título de Cirujano Dentista / Autor no autoriza el acceso a texto completo de su documento / INTRODUCCIÓN: La diabetes mellitus tipo 2 (DM2) es un trastorno metabólico debido a una deficiencia progresiva en la secreción de insulina. El control glicémico en pacientes con DM2 se debe mantener en niveles adecuados; si estos no se mantienen, pueden presentarse consecuencias negativas locales y sistémicas importantes. El examen de Hemoglobina Glicosilada (HbA1C) se utiliza para definir el verdadero control glicémico de la enfermedad, por lo que debe mantenerse en niveles adecuados. Las levaduras del género Candida son microorganismos comensales, que cambian a una forma patógena al existir alteración en los mecanismos de defensa del hospedero. La DM2, especialmente en estado descompensado, se ha asociado al desarrollo de patologías provocadas por infección con microorganismos oportunistas, en especial por levaduras del género Candida. MATERIAL Y MÉTODOS: Se obtuvieron muestras de saliva de 52 sujetos voluntarios mayores de 30 años con diagnóstico de DM2, previo consentimiento informado firmado. El grupo se dividió según su condición metabólica en diabéticos compensados (HbA1C < 7%) y no compensados (HbA1C > 7%). Un volumen de 100 μl de saliva se sembró en placas de Agar Sabouraud Tetraciclina y CHROMagar Candida ®, las que se incubaron durante 48 horas a 30 ºC, hasta el desarrollo de colonias. En estas placas se estimó el número de células viables y se identificaron presuntivamente las especies de Candida presente según su coloración. La identidad de las colonias observadas se confirmó molecularmente mediante Reacción en Cadena de la Polimerasa (PCR) y bioquímicamente mediante el Sistema de Identificación API ID32C ®. RESULTADOS: El promedio de HbA1C de la muestra total correspondió a 8,16 %, donde 40 correspondieron a mujeres y 12 a hombres, entre 33 y 82 años de edad. La portación de levaduras no tuvo diferencias significativas en relación al género y al estado metabólico (p > 0,05) pero fue mayor al aumentar la edad (p = 0,024). La cantidad de UFC, medida en rangos mayor o menor a 400 UFC/ml fue mayor en el 6 grupo descompensado (p = 0,025) y al aumentar la edad (p = 0,017). Se identificaron 6 especies, donde la más aislada en la muestra fue C. albicans con un 66,1 % y en 38 (97,4 %) del total de sujetos portadores, seguido por C. glabrata. La diversidad de especies no se relacionó a género ni al estado metabólico (p > 0,05) pero sí a la edad (p = 0,049). CONCLUSIONES: La descompensación metabólica en pacientes con DM2 se asoció a una mayor cantidad de UFC/ml no así con una mayor diversidad de especies.

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