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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.
531

Romanian Dative Clitic Dependencies in Raising Constructions

Geber, Dana January 2011 (has links)
The goal of this work is to provide an account of dative clitic dependencies in constructions with raising verbs such as to seem in Romanian. Dative clitic experiencers as quirky subjects and dative clitics in clitic left dislocation (CLLD) constructions are discussed from a syntactic point of view and experimentally tested in a psycholinguistics study. The study contributes to current innovations in the Minimalist Program, presenting new perspectives on Romanian clitic dependencies in raising constructions partially addressed in earlier generative grammar. This study poses new questions regarding raising, the intervention effects of dative clitic experiencers, and the effects of clitic dependencies in ditransitive constructions. Chapter II presents an overview of Romanian raising constructions without dative experiencers. I show that Romanian possesses three raising constructions, based on the type of the embedded clause: subjunctive, infinitive, and indicative. Each of these has three potential locations for the nominative subject, argued to be generated in the embedded clause. Formal mechanisms such as Long Distance and Multiple Agree, Movement, Case and EPP are considered independent of one another. Dative clitic experiencers in raising constructions, analyzed in Chapter III, are claimed to be quirky subjects and to structurally occupy the highest position in the sentence. Having established the role of dative clitic experiencers, I discuss raising constructions involving dative experiencers generated and/or surfacing in various positions, and their effects on operations such as Agree and Move. I then discuss Experiencer Islands, formed by matrix and embedded experiencers in the same utterance, and present the contexts in which they occur. A Grammaticality Judgment Test confirms the existence of such restriction in Romanian. Furthermore, I present an analysis of Experiencer Islands and discuss observed exceptions to the restriction. Dative clitic dependencies such as CLLD constructions and Long Distance CLLD Constructions are also analyzed in this thesis. The experimental study presented in Chapter IV supports theoretical claims and demonstrates that Romanian speakers are aware of dative clitic dependencies, such as clitic experiencer dependencies and clitic dependencies in CLLD constructions, possess the grammatical knowledge of biclausal constructions involving dative clitic dependencies and have the ability to recognize such dependencies.
532

Simulation of Myocardium Motion and Blood Flow in the Heart with Fluid-Structure Interaction

Doyle, Matthew Gerard January 2011 (has links)
The heart is a complex organ and much is still unknown about its mechanical function. In order to use simulations to study heart mechanics, fluid and solid components and their interaction should be incorporated into any numerical model. Many previous studies have focused on myocardium motion or blood flow separately, while neglecting their interaction. Previous fluid-structure interaction (FSI) simulations of heart mechanics have made simplifying assumptions about their solid models, which prevented them from accurately predicting the stress-stain behaviour of the myocardium. In this work, a numerical model of the canine left ventricle (LV) is presented, which serves to address the limitations of previous studies. A canine LV myocardium material model was developed for use in conjunction with a commercial finite element code. The material model was modified from its original form to make it suitable for use in simulations. Further, numerical constraints were imposed when calculating the material parameter values, to ensure that the model would be strictly convex. An initial geometry and non-zero stress state are required to start cardiac cycle simulations. These were generated by the static inflation of a passive LV model to an end-diastolic pressure. Comparisons with previous measurements verified that the calculated geometry was representative of end diastole. Stresses calculated at the specified end diastolic pressure showed complex spatial variations, illustrating the superiority of the present approach over a specification of an arbitrary stress distribution to an end-diastolic geometry. In the third part of this study, FSI simulations of the mechanics of the LV were performed over the cardiac cycle. Calculated LV cavity pressures agreed well with previous measurements during most of the cardiac cycle, but deviated from them during rapid filling, which resulted in non-physiological backflow. This study is the first one to present a detailed analysis of the temporal and spatial variations of the properties of both the solid and the fluid components of the canine LV. The observed development of non-uniform pressure distributions in the LV cavity confirms the advantage of performing FSI simulations rather than imposing a uniform fluid pressure on the inner surface of the myocardium during solid-only simulations.
533

Goodness-of-Fit for Length-Biased Survival Data with Right-Censoring

Younger, Jaime January 2012 (has links)
Cross-sectional surveys are often used in epidemiological studies to identify subjects with a disease. When estimating the survival function from onset of disease, this sampling mechanism introduces bias, which must be accounted for. If the onset times of the disease are assumed to be coming from a stationary Poisson process, this bias, which is caused by the sampling of prevalent rather than incident cases, is termed length-bias. A one-sample Kolomogorov-Smirnov type of goodness-of-fit test for right-censored length-biased data is proposed and investigated with Weibull, log-normal and log-logistic models. Algorithms detailing how to efficiently generate right-censored length-biased survival data of these parametric forms are given. Simulation is employed to assess the effects of sample size and censoring on the power of the test. Finally, the test is used to evaluate the goodness-of-fit using length-biased survival data of patients with dementia from the Canadian Study of Health and Aging.
534

Proměny politického systému Bollívie po nástupu Eva Moralese / Changes of the Bolivian political system after Evo Morales` accession to the power

Hudcovská, Jana January 2009 (has links)
The diploma thesis is focused on the changes in the political system of Bolivia .after Evo Morales` accession to the power. The aim of this thesis is to investigte the changes of the Bolivian political system and the changes of its character under Morales` rule. The main attention is focused on the changes of the institutional base of the political system, the forms of governance and the character of the Bolivian political representation. The issue is discussed in the frame of the current Latin American left governments.
535

Metamaterial stepped impedance resonator filters for wireless communication systems

Karimian, Shokrollah January 2011 (has links)
This thesis introduces, for the first time, Stepped Impedance Resonator (SIR) bandpass filters (BPF) based on Composite Right/Left-Handed (CRLH) transmission lines. In other words, a novel approach in design of BPFs for RF and microwave applications is successfully proposed and examined, which can serve both miniaturisation and performance enhancement purposes. In conducting this research, design, development and optimisation procedures and techniques for the proposed BPFs have been presented. Theoretical, numerical and experimental results have confirmed that these filters are capable of significantly reducing the size while maintaining the integrity of the filter performance; and in some cases, extensively enhancing the performance.Two λg/4-type CRLH SIRs are designed and characterised based on the available equations. ADS lumped-element equivalent circuit model and HFSS full-wave electromagnetic simulation, and measurement results prove that both CRLH SIRs surpassed their RH counterparts, in terms of both size and performance. Indeed, comparison of the first CRLH SIR with its RH counterpart revealed a 35% size (length) reduction. The second CRLH SIR design is measured to be 66% smaller than its RH counterpart and 14% smaller than the initial CRLH SIR. In addition, simulation and measurement results reveal that an intelligently designed CRLH SIR shows a better quality factor Q and input impedance |Zin| response, and provides higher design flexibility. Phase unwrapping and energy (current) flow analysis have been used to prove left-handedness of the CRLH SIRs. The concept is extended to propose multi-section (λg/2-type and tri-section SIRs) and tunable CRLH SIRs. Numerical analysis and obtained results show that the λg/2-type CRLH SIR benefits from a 45% size (length) reduction compared to its RH counterpart, and a better |Zin| response. The results obtained from the tri-section CRLH SIR (TSSIR), clearly show that the TSSIR is capable of relocating (and minimising) the multiple spurious resonance frequencies, while maintaining the same fundamental frequency f0. As such, no spurious frequency is observed before 8 GHz. Also, measurements indicated that the CRLH TSSIR is not only 30% smaller in length compared to its RH counterpart, it was even 28% smaller than a two-section RH SIR resonating at the same frequency of 2.5 GHz. In addition, the tuning capability of the ferrite CRLH SIR is illustrated when the operating frequency of the resonator is tuned from 5.1 GHz to 5.4 GHz, and 5.65 GHz for H0 = 2000, 2250, and 2500 Oe, respectively.These SIRs are then combined and configured to form two main categories of CRLH SIR bandpass filters: PCB filters based on RT Duroid and MMIC filters based on GaAs. In both filters, the homogeneity condition has been satisfied by ensuring that the longest length is much less than λg (in this case l = λg/12) for PCB-based filters and l = λg/14 for MMIC filters at the centre frequency of the filters. The first PCB-based CRLH SIR filter, which has been designed to operate at 2.75 GHz, is measured 24mm × 28mm. HFSS 3-D full-wave simulations and measurement results of this filter reveal that, with an insertion loss of -2.6dB and return loss of -21.5dB, the filter not only has a very good selectivity, but also is extremely efficient in extending the free-spurious stop-band, pushing the first spurious response to around 11 GHz (about 4×f0). The second PCB-based CRLH SIR filter has much smaller size, measuring overall filter dimensions of 6mm × 5.14mm. This filter also benefits from a smaller resonator size, improved overall coupling and a more controllable circuit. Theory, full-wave simulation and measurement results demonstrate that, with an insertion loss of -1dB and return loss of -34dB, the miniaturised CRLH SIR filter proves very successful as it was about 80% smaller in size compared to its RH counterpart with the same centre frequency, while maintaining the integrity of the filter performance. Moreover, the miniaturised CRLH SIR BPF is significantly more controllable in its dimensions and response due to the fact that more elementary parameters are available in the CRLH configuration.The MMIC CRLH SIR bandpass filters are then proposed with an emphasis on further size reduction with maintenance (or enhancement) of their transmission responses. As such, two classes of MMIC filters were designed: the first one is very small measuring 3.2mm × 3.4mm, with an insertion loss of -5.3dB at the centre frequency 3.1 GHz. The filter also shows good attenuation both before and after the passband with its first spurious frequency occurring at 13.52 GHz (i.e. > 4×f0). The second set of MMIC filters employed multilayer topology to reduce the filter size. It has been clearly shown that with an intelligent design, the size (dimension) limitations of the PCB-based filters have been overcome by using the MMIC technology, resulting in filters with significantly reduced sizes - design I: 1.32mm×3.35mm, and design II: 1.4mm × 1.5mm. It has also been observed that MMIC structures are generally exposed to inevitable losses, though steps can be taken to reduce such losses.
536

Textová a obsahová analýza jazyka současné krajně pravicové a krajně levicové mládeže / Textual Content Analysis of the Contemprorary Extreme Right and Extreme Left Youth Organization

Brejchová, Pavla January 2011 (has links)
This paper is dealing with a textual content analysis of extreme right and extreme left youth organizations. A methodological framework for the analysis is described in chapter one. A special attention is devoting to the content analysis method. Ideological and theoretical placement of extreme right and extreme left are discussed in chapter two. This chapter is also dealing with the particular associations (KSM, SMKČ, DM). The content analysis ant its results are presented in chapter three.
537

Brazilská levice na počátku 21. století. Od politické alternativy k mocenskému kartelu? / Brazilian Left at the beginning of the 21st Century. From Political Alternative to Cartel of Power?

Němec, Jan January 2005 (has links)
The thesis deals with the transformation of the Brazilian Workers' Party (Partido dos Trabalhadores, PT). Its aim is to identify reasons for more than a decade interval between the renewal of direct presidential election under the universal suffrage and the victory of the left in a society that is marked by extreme inequality of wealth distribution. The second issue which is covered is how the party managed to consolidate power and keep it for three consecutive terms. Using modified concepts of mass, catch-all and cartel party the author tests the hypothesis that the electoral victory of the left was conditioned by the domination of the leftist side of political spectrum by the PT, as a result of building a mass (program-oriented) party, which subsequently tailored its campaign to focus on centrist voters (shift to the catch-all format, or votes-oriented party). The maintenance of power is based on crafting oversized coalitions with parties across the political spectrum, i.e. including the right-wing parties. However, these coalitions are created only to support government; the Workers' Party never forms electoral coalitions with prominent rightest parties. Furthermore, the thesis discusses the functioning of the so-called coalitional presidentialism, the typologies of current leftist governments in Latin America and also presents the basic elements of the Brazilian political system.
538

L'espace et l'humain : les cadres de référence, leur développement et leurs relations avec les confusions spatiales / Space and human : frames of reference, development and spatial confusions

Courrèges, Sandra 13 April 2011 (has links)
RésuméLa thèse porte sur les représentations spatiales et en particulier sur les cadres de référence spatiale. Ils permettent la localisation d’objets par rapport à d’autres dans un espace proche, comme dans l’exemple : « le sel est à gauche du poivre ». Il existe différents types de références : centré sur soi, centré sur l’objet et centré sur l’environnement. Celles qui sont préférentiellement utilisées par un individu dépendent de sa langue et de sa culture.Dans un premier temps, le développement des cadres de référence est analysé chez des sujets de culture française de 3 à 21 ans, grâce aux tâches du paradigme de rotation à 180° (Levinson, 2003). Dans un second temps, les relations entre les confusions gauche/droite et l’utilisation de cadres de référence sont examinées chez des adultes français, en s’appuyant sur un questionnaire d’auto-évaluation et sur une tâche du paradigme de rotation. Les résultats permettent de dessiner un chemin développemental concernant les cadres de référence en France, selon le modèle de la Redescription Représentationnelle de Karmiloff-Smith (1992). Ils montrent également le lien entre les confusions gauche/droite et les types de références spatiales utilisées chez certains adultes. / The thesis is about spatial representations, especially spatial frames of reference, which are used to locate an object with respect to another in a small-scale space, for example: « the salt is to the left of the pepper ». Different references exist: self-centred, object-centred and environment-centred. The references preferentially employed by a subject depend on his language and culture.First of all, the development of frames of reference is analysed with French subjects from 3 to 21 years of age, thanks to 180° rotation paradigm tasks (Levinson, 2003). Secondly, the relations between left/right confusions and the use of frames of reference are examined with French adults, with a self-judgment questionnaire and a rotation paradigm task.Results show that the development of frames of reference in France follows the predictions of the Representational Redescription model of Karmiloff-Smith (1992). They also highlight a link between left/right confusions and spatial references used by some adults.
539

Comparing chest X-rays with ultrasound for the prediction of left atrial size at Pretoria Academic hospital

Quinton, S.J. (Susanna Jacoba) 06 July 2007 (has links)
Estimates of left atrial size in patients with suspected cardiac disease play an important role in diagnostic medicine. Left atrial size is used in predicting prognosis and events, as well as treatment decisions. Two methods are commonly used to estimate left atrial size: chest radiography and cardiac ultrasound. This study aims to determine the test characteristics of chest radiography and compare the use of radiographs to cardiac ultrasound (the gold standard test). Data from patients older than 18 years admitted to Pretoria Academic Hospital during 2000-2003 who had both chest X-rays and cardiac ultrasound were included in this cross-sectional, retrospective analysis. Chest X-rays were classified into three quality classes, and the sub-carinal angle (SCA) and sub-angle distance (SAD) were measured twice in all available X-rays by two observers. Intra- and interobserver variability (3 methods) as well as the predictive value of the SCA and SAD measurements were determined using logistic regression (with left atrial size determined by ultrasound as comparator). P-values < 0.05 were regarded as statistically significant for all comparisons. Data for 159 patients were available (154 cardiac ultrasounds and 178 chest radiographs). Intraobserver variability regarding chest X-ray measurements was low with almost perfect concordance (P=0.000). Interobserver variability was higher for supine X-rays. Using logistic regression, a linear model was identified which was statistically significant only for erect X-rays. While goodness-of-fit analysis showed that the model fits the data, performance characteristics were poor, with high sensitivity and low specificity, and an area under the ROC curve of 0.62-0.63, depending on type of X-ray and measurement (SCA or SAD). Linearity in the logit of the dependent variable was assessed, and found to be present at the extremes of carinal angle measurements for the supine X-ray data and in the first three quartiles for erect X-ray data. A non-linear model determined by fractional polynomial analysis did not perform significantly better than the original linear model. Cut-off values for the SCA of 72o and 84o (erect and supine X-rays, respectively) were found to give the best compromise between sensitivity and specificity. The corresponding cut-off values for SAD were 24.1mm and 26.9mm. Assessment of either SCA or SAD to determine left atrial size is equivalent and repeatable, both within the same observer, and between two observers (less so for supine X-rays). While this measure is precise, it was found not to be very accurate. Therefore, chest X-rays are not reliable in predicting left atrial enlargement. / Dissertation (MSc (Clinical Epidemiology))--University of Pretoria, 2007. / Clinical Epidemiology / unrestricted
540

Interações do polimorfismo -930A/G da p22phox em pacientes hipertensos / Interactions of p22phox -930A/G polymorphism in hypertensive patients

Sales, Maria Lilian 22 August 2006 (has links)
Orientador: Wilson Nadruz Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T22:16:04Z (GMT). No. of bitstreams: 1 Sales_MariaLilian_M.pdf: 699325 bytes, checksum: c06952a4445a0175323db1f2dd969bed (MD5) Previous issue date: 2006 / Resumo: A subunidade p22phox é um componente essencial do complexo enzimático NADPH oxidase, o qual é considerado a principal fonte de produtos do stress oxidativo no sistema cardiovascular. O alelo -930G da p22phox tem sido associado com maior stress oxidativo mediado pela NADPH oxidase e hipertensão arterial. Nós recentemente demonstramos que a hipertrofia do ventrículo esquerdo é acompanhada de aumento na expressão miocárdica de p22phox em ratos submetidos à coarctação da aorta, sugerindo que esta proteína pode estar envolvida em lesões de órgão-alvo induzidas por hipertensão, mais especificamente na hipertrofia cardíaca. Foi pesquisada a prevalência deste polimorfismo em 160 indivíduos acompanhados no Ambulatório de Hipertensão Arterial Sistêmica da UNICAMP, e realizada a correlação desta variante com a massa e geometria ventricular esquerda, lesão renal e perfil metabólico destes pacientes. Não foram encontradas correlações significativas entre este polimorfismo e lesão renal ou estrutural em ventrículo esquerdo. Porém, nos indivíduos com genótipo GG foram encontrados níveis séricos de Triglicérides e de LDL colesterol significativamente mais baixos / Abstract: The p22phox subunit is an essential component of the NAD(P)H oxidase enzymatic complex, which is considered the major source of oxidative stress products in the cardiovascular system. The -930G allele of p22-phox has been associated with higher promoter activity, increased NAD(P)H oxidase-mediated oxidative stress and hypertension. NADPH oxidases have been proved important in the pathogenesis of renal damage in models of hypertension. We recently reported that left ventricular hypertrophy is accompanied by increased myocardial p22-phox expression in aortic-banded rats, suggesting that this protein might be involved in hypertensive cardiac hypertrophy. Thus, the aim of the present report was to investigate the role of p22phox -930A/G polymorphism on cardiac hypertrophy, renal damage and metabolic profile in hypertensive patients. We research the -930A/G polimorfism prevalence in 160 hypertensive subjects from Ambulatory Hypertension Unit - UNICAMP. The follow-up was between 2005 and 2006. The variant -930A/G has not relationship with alterations in ventricular structure and with renal damage markers. However, in GG subjects was associated with lower seric levels of Triglycerides and LDL-cholesterol This finding suggest a association between this variant GG genotype with a best metabolic profile in hypertensives / Mestrado / Clinica Medica / Mestre em Clinica Medica

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