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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.
371

Left Ventricular Dynamics During Exercise in Endurance Athletes

Sundstedt, Milena January 2007 (has links)
<p>Large quantities of data have described left ventricular adaptation to endurance training, but basic concepts on left ventricular performance during exercise remain controversial. In this thesis, we present the results of studies of left ventricular dynamics during exercise in 89 endurance-trained athletes.</p><p>Using radionuclide ventriculography, 35 female and 30 male endurance athletes were studied in supine position. During supine exercise at 70% of the age-expected maximal heart rate, the adjustments in left ventricular volumes were small, suggesting a high preload before exercise. Stroke volume increased by changes in the left ventricular end-diastolic volumes but no changes were observed in the end-systolic volumes. Moreover, no significant differences were noted between male and female athletes.</p><p>Contrast echocardiography was utilized when 24 male endurance athletes were studied during upright exercise. An almost linear increase in stroke volume was seen from upright rest to upright exercise at a heart rate of 160 beats per minute. Stroke volume increased by an almost linear increase in end-diastolic volume and showed an initial small decrease in end-systolic volume. The left ventricular cavity became geometrically more spherical with the largest increase in the left ventricular end-diastolic short-axis cavity diameters in the mid and apical part of the left ventricle. Left ventricular long-axis length obtained from the epicardial apex to the middle of the mitral annulus at end-diastole showed no significant change from rest to exercise. The mitral annulus motion contributed to more than 50% of the stroke volume during exercise with no significant difference between septal and lateral annular motion at peak exercise. Major changes were observed in left ventricular filling indices during upright exercise. The mean transmitral pressure gradient showed a linear increase and increased several times as the mean diastolic time decreased, with large reductions in mean left ventricular filling time. Despite the shortened filling time, the heart was able to increase the filling rate (measured as volume per time) five times. This observation verifies that the heart has large reserves at rest and reveals the increase in capacity during exercise.</p>
372

Kiezdeutsch as a test case for the interaction between grammar and information structure

Wiese, Heike, Freywald, Ulrike, Mayr, Katharina January 2009 (has links)
This paper deals with Kiezdeutsch, a way of speaking that emerged among adolescents in multiethnic urban neighbourhoods of Germany. We show that, in Kiezdeutsch, we find evidence for both grammatical reduction and new developments in the domain of information structure, and hypothesise that this points to a systematic interaction between grammar and information structure, between weakened grammatical constraints and a more liberal realisation of information-structural preferences. We show that Kiezdeutsch can serve as an interesting test case for such an interaction, that this youth language is a multiethnolect, that is, a new variety that is spoken by speakers from a multitude of ethnic backgrounds, including German, and forms a dynamic linguistic system of its own, thus allowing for systematic developments on grammatical levels and their interfaces with extragrammatical domains.
373

Direct and indirect aboutness topics

Endriss, Cornelia, Hinterwimmer, Stefan January 2007 (has links)
We propose a definition of aboutness topicality that not only encompasses individual denoting DPs, but also indefinites. We concentrate on the interpretative effects of marking indefinites as topics: they either receive widest scope in their clause, or they are interpreted in the restrictor of an overt or covert Q-adverb. We show that in the first case they are direct aboutness topics insofar as they are the subject of a predication expressed by the comment, while in the second case they are indirect aboutness topics: they define the subject of a higher-order predication – namely the set of situations that the respective Q-adverb quantifies over.
374

Surgical treatment in chronic aortic regurgitation : Timing, results, prognosis and left ventricular function

Tamás, Éva January 2008 (has links)
Chronic aortic regurgitation (AR) of varying degree affects 13% of men and 8.5% of women. In persons with severe AR, the expected length of life and its quality are influenced. Some individuals remain asymptomatic for a long period, due to effective compensatory mechanisms, but dysfunction of the left ventricle (LV) usually begins before symptoms appear and can be irreversible by then. This thesis addresses questions of LV function and optimal time for operation of patients suffering from chronic AR. Moreover, detailed echocardiographic studies of the anatomy of the normal aortic valve have been performed to obtain a better understanding of the in vivo anatomic relations within the aortic root. Patients with chronic AR, without concomitant cardiac disease, were studied both retrospectively (n=88) and prospectively (n=29) and the aortic valves of persons (n=32) free from cardiac disease were investigated. For the retrospectively studied patients, survival was 82% at 10 years which is an improvement compared with previously published results. The majority of the patients, however, had LV dysfunction preoperatively. By studying patients prospectively by echocardiography, radionuclide ventriculography (MUGA) and cardiopulmonary exercise testing (CPET) our aim was to evaluate the predictive value of measurements of LV function at rest and during exercise for postoperative outcome. LV diameters were markedly elevated prior to and diminished significantly after surgery. Patients with an abnormal exercise ejection fraction (EF) response by MUGA preoperatively, presented the same reaction postoperatively. This could not be predicted by LV function determination at rest, or by NYHA functional class. In spite of median NYHA class II, these patients had a low work capacity on CPET, which was neither improved 6 months postoperatively nor correlated to echocardiographic LV dimensions. Thus, both MUGA and CPET may be useful complements for timing of surgery in patients with chronic AR. Assuming that patients would benefit from preservation of their native valves the normal aortic valve was studied to gain detailed information about the echocardiographic anatomy and relations within the normal aortic root. This extended examination of the aortic root may facilitate a better planning of aortic valve‐preserving interventions in the future.
375

Left ventricular hypertrophy and the insulin resistance syndrome

Sundström, Johan January 2001 (has links)
Left ventricular hypertrophy (LVH) and the insulin resistance syndrome are common conditions associated with a markedly increased cardiovascular risk. In a fairly large prospective longitudinal study of men from the general population, we found that an unfavorable serum fatty acid profile and components of the insulin resistance syndrome such as dyslipidemia, obesity and hypertension at age 50 predicted the prevalence of LVH at age 70. In cross-sectional analyses at age 70, several components of the insulin resistance syndrome were significantly related to left ventricular relative wall thickness and concentric remodeling, but less to LVH. Left ventricular relative wall thickness was inversely related to insulin sensitivity in skeletal muscle and borderline significantly directly related to insulin sensitivity in the myocardium in a healthy, normotensive sample of the cohort investigated with positron emission tomography, whereas left ventricular mass index was not related to myocardial or skeletal muscle insulin sensitivity. At age 70, echocardiographic LVH was related to a variety of common electrocardiographic diagnoses. In a prospective mortality analysis with baseline at age 70 and a median follow-up time of five years, echocardiographic and electrocardiographic LVH predicted mortality independently of each other and of other cardiovascular risk factors, implying that echocardiographic and electrocardiographic LVH in part carry different prognostic information. In summary, components of the insulin resistance syndrome predicted LVH twenty years later, but were cross-sectionally more related to increased left ventricular relative wall thickness and concentric remodeling. Echocardiographic and electrocardiographic LVH predicted mortality independently of each other and of components of the insulin resistance syndrome.
376

Left Ventricular Dynamics During Exercise in Endurance Athletes

Sundstedt, Milena January 2007 (has links)
Large quantities of data have described left ventricular adaptation to endurance training, but basic concepts on left ventricular performance during exercise remain controversial. In this thesis, we present the results of studies of left ventricular dynamics during exercise in 89 endurance-trained athletes. Using radionuclide ventriculography, 35 female and 30 male endurance athletes were studied in supine position. During supine exercise at 70% of the age-expected maximal heart rate, the adjustments in left ventricular volumes were small, suggesting a high preload before exercise. Stroke volume increased by changes in the left ventricular end-diastolic volumes but no changes were observed in the end-systolic volumes. Moreover, no significant differences were noted between male and female athletes. Contrast echocardiography was utilized when 24 male endurance athletes were studied during upright exercise. An almost linear increase in stroke volume was seen from upright rest to upright exercise at a heart rate of 160 beats per minute. Stroke volume increased by an almost linear increase in end-diastolic volume and showed an initial small decrease in end-systolic volume. The left ventricular cavity became geometrically more spherical with the largest increase in the left ventricular end-diastolic short-axis cavity diameters in the mid and apical part of the left ventricle. Left ventricular long-axis length obtained from the epicardial apex to the middle of the mitral annulus at end-diastole showed no significant change from rest to exercise. The mitral annulus motion contributed to more than 50% of the stroke volume during exercise with no significant difference between septal and lateral annular motion at peak exercise. Major changes were observed in left ventricular filling indices during upright exercise. The mean transmitral pressure gradient showed a linear increase and increased several times as the mean diastolic time decreased, with large reductions in mean left ventricular filling time. Despite the shortened filling time, the heart was able to increase the filling rate (measured as volume per time) five times. This observation verifies that the heart has large reserves at rest and reveals the increase in capacity during exercise.
377

Demokratisering i Latinamerika under 1900-talet : – vänstern och demokratins fördjupning

Nilsson, Martin January 2005 (has links)
This study deals with the issue of democratization in Latin America during the 20th century, and in particular the role of the left in this process. The purpose of this study is to empirically analyze the role of the left as a political actor in the process of democratization toward the deepening of the democratic rule in Latin America. The research questions are: what role did the left have in the transitions to electoral democracies during the 20th century in Latin America? Why did the left have the role it had in the transitions? How does the left’s view of democracy affect the transition to electoral democracy, and the further democratization to deepen democratic rule? What structural constraints affect the left’s ability to deepen democratic rule? A comparative qualitative method and different theoretical concepts of democracy, democratization, elite perspective, mobilization and organizations have been used, and examples from different Latin American cases are given. One empirical conclusion is that the role of the left in the transitions to electoral democracies varies from participation with active left leaders, collective left actions, to not have any significant role at all. A second empirical conclusion is that in cases where left wing governments have tried to enforce a model of participatory democracy, the result has been “ coup d’état” or rebellions conducted by military forces and supported by the economic elite and the United States of America. In other cases when left parties in government instead have remained within the framework of an elite democracy, the result has rather been stabilization of the liberal democratic rule. The main theoretical conclusions are as follows: the theoretical discussion about democratic consolidation and the deepening of democracy have to consider that different actors’ (in this study the left) preferences for various models of democracy differ; the actors’ view of democracy matter in the game of democratic development and democratic consolidation; and the relations between the elite actors’ preferences for different models of democracy determine the outcome of a specific form of democratic model (in this study electoral democracy, liberal democracy or participatory democracy).
378

Faderskapet : – en litteraturstudie om blivande/nyblivna pappors upplevelser av barnmorskors/sjuksköterskors bemötande / Fatherhood : – a literature study of prospective/new fathers experiences of midwives/nurses encounting

Hirvikoski Huusko, Linda, Karlsson, Mikaela January 2010 (has links)
Många studier om föräldraskap är mest fokuserade på mammors upplevelser av graviditet och förlossning. Även om mammorna föder barnen och är i behov av mer vård än papporna, är det två personer som blir föräldrar. Pappor behöver också uppmärksamhet och kunskap för att bli bra föräldrar. Svenska barnmorskor och sjuksköterskor saknar ibland kunskap om mäns upplevelser av graviditet och förlossning. Syftet med denna studie är att belysa blivande/nyblivna pappors upplevelser av barnmorskors/sjuksköterskors bemötande. En litteraturstudie valdes för denna studie. 14 artiklar analyserades och de svarade på studiens syfte. I resultatet framkommer två teman, att bli bekräftad och att få ett stöd och att vara ett stöd, med tillhörande sex underteman. Pappor verkar vara de bortglömda föräldrarna. Många pappor känner att de är utelämnade och känner sig ofta oförberedda på själva förlossningen. Det framkommer även att de pappor som får extra förberedelser känner sig mer säkra under förlossningen och nyföddhetsperioden.
379

Optical Studies ofNano-Structures in the BeetleCetonia Aurata

Shamim, Rizwana January 2009 (has links)
The main objective of this thesis is to study the polarization effects of the beetle Cetonia aurata using Mueller-matrix ellipsometry. The outer shell of the beetle consists of complex microstructures which control the polarization of the reflected light. It has metallic appearance which originates from helicoidal structures. When these microstructures are exposed to polarized or unpolarized light, only left-handed circularly polarized light is reflected. Moreover, the exo-skeleton of the beetle absorbs right-handed polarized light. Multichannel Mueller-matrix ellipsometer or dual rotating compensator ellipsometer, called RC2, from J.A.Woollam is used to measure the polarization caused by different parts of beetle’s body. The 16 Mueller matrix elements are measured in the spectral range 400-800 nm at multiple angles of incidencein the range 400-700. An Optical model is developed to help us understand the nature and type of microstructure which only reflects the green colour circularly polarized light. With the help of multiparametric modeling, we were able to find optical properties and structural parameters. The parameters are: the number of layers, the numbers of sub-layers, their thicknesses, and the orientation with respect to optical axes. This optical model describes the nanostructures which provide the reflection properties similar to the nanostructure found in the beetle Cetonia aurata. The model is also useful for analysis of the optical response data of different materials with multilayer structures.
380

Every Child Left Behind: The Effects of No Child Left Behind on Private School Enrollment

Ogburn, Julia J 01 April 2013 (has links)
The No Child Left Behind Act of 2001 is designed to help create a national minimum standard in the United States‘ public education system by requiring states to implement accountability systems. I examine the effect of No Child Left Behind on private school enrollment using a difference in differences model. Using data from the Private School Universe Survey, conducted by the National Center for Education Statistics, which is a survey conducted every two years and is mandatory for each American private school‘s administration to complete, I can evaluate the movement between public and private schools during the period when the requirements of No Child Left Behind were being implemented. I hypothesize that public schools have moved resources away from high achieving students toward the marginal students causing the high achieving students to enroll in private schools. Hence, private school enrollment will have increased due to No Child Left Behind. I find through my regressions that this hypothesis is true; the percentage of school-aged children in private schools increases after the signing of the No Child Left Behind Act.

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