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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.
71

Roles of mitochondria in the multidrug resistance in R-HepG2 cells. / CUHK electronic theses & dissertations collection

January 2002 (has links)
by Li Yanchun. / "August 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 193-213). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
72

Multiple comparisons with a control in each of several groups with heterogeneous group variances.

January 2003 (has links)
Chan Tat-on. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 39-40). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Multiple Comparison Procedures --- p.1 / Chapter 1.2 --- One-step MCCP --- p.2 / Chapter 1.3 --- Stepwise MCCP --- p.7 / Chapter 1.4 --- Thesis Objectives --- p.10 / Chapter Chapter 2 --- One-step MCCP with Heterogeneous Group Variances --- p.11 / Chapter 2.1 --- The Model --- p.11 / Chapter 2.2 --- Test Statistics --- p.12 / Chapter 2.3 --- Testing and Estimation --- p.15 / Chapter Chapter 3 --- Stepwise MCCP with Heterogeneous Group Variances --- p.17 / Chapter 3.1 --- The Model --- p.17 / Chapter 3.2 --- Testing Procedure --- p.17 / Chapter 3.3 --- Simulation Study --- p.18 / Chapter 3.3.1 --- Average power --- p.19 / Chapter 3.3.2 --- Family wise Type I error rate --- p.20 / Chapter 3.3.3 --- Simulation procedures --- p.21 / Chapter 3.3.4 --- Choice of parameter configurations --- p.23 / Chapter 3.3.5 --- Simulation results --- p.24 / Chapter 3.3.6 --- Summary --- p.28 / Chapter Chapter 4 --- Numerical Example --- p.33 / Chapter 4.1 --- SS procedures --- p.34 / Chapter 4.2 --- SW procedures --- p.35 / Chapter Chapter 5 --- Further Research --- p.38 / References --- p.39
73

Deeskalation der Immuntherapie bei Patienten mit Multipler Sklerose / Deescalation of Immuntherapy in patients with Multiple Sclerosis

Oehler, Steffen Claus January 2015 (has links) (PDF)
Die vorliegende Arbeit ist die erste, die sich mit der Frage beschäftigt, mit welcher zur Deeskalation eingesetzten Therapie nach Beendigung einer Eskalationstherapie mit Mitoxantron am besten Krankheitsstabilität erreicht werden kann bzw. ob Patienten-/Krankheitscharakteristika existieren, die eine bestimmte Nachfolge-Therapie favorisieren. Trotz neuer Behandlungsmöglichkeiten der hochaktiven MS mit Fingolimod, Natalizumab und Alemtuzumab hat Mitoxantron im klinischen Alltag nach wie vor einen hohen Stellenwert, so dass die Fragestellung dieser Studie weiter relevant ist. Es zeigten sich keine Patientencharakteristika, die auf eine erfolgsversprechende Therapie in der Deeskalationsphase nach Mitoxantron schließen ließen. Bei Patienten, bei denen während der Eskalation mit Mitoxantron die Dosis reduziert werden konnte, wurden während der Deeskalationstherapie ein stabilerer Verlauf und weniger Therapiewechsel beobachtet. Bei Patienten, die wegen einer rein chronischen Krankheitsprogredienz eskaliert wurden, trat eine Verschlechterung nach Deeskalation häufiger auf als bei denjenigen, welche wegen Schubaktivität eskaliert wurden. Die Aussagekraft der Daten wird durch die nur niedrige Anzahl der in diese Studie eingeschlossenen Patienten limitiert. Rekrutierungsprobleme stellten die Hauptursache für die geringe Anzahl der Studienteilnehmer dar. / Deescalation of Immuntherapy in patients with Multiple Sclerosis
74

Korrelation der Elastizität von Rückenmarksgewebe und histologischen Veränderungen in einem Tiermodell der Multiplen Sklerose / Correlation of elasticity of spinal cord tissues and histological changes in an animal model of multiple sclerosis

Groth, Sofie Claire January 2019 (has links) (PDF)
Multiple Sklerose ist eine der häufigsten und bedeutsamsten entzündlichen Autoimmunerkrankungen bei jungen Erwachsenen. Obwohl die klassischen Kennzeichen der Krankheit wie Infiltration von Immunzellen, Demyelinisierung, Astrogliose und axonale Schädigung bekannt sind, sind die genauen Ursachen und die zugrundeliegende Pathophysiologie noch nicht geklärt. In der Fachliteratur wurden bereits biomechanische Veränderungen mit histologischen Veränderungen im ZNS in Verbindung gebracht. Der genaue Zusammenhang und das Ausmaß zwischen den mechanischen Gewebeeigenschaften und den zugrundeliegenden histologischen Veränderungen wurde bis heute jedoch nur wenig erforscht. Die vorliegende Arbeit untersuchte in ihrem methodischen Rahmen den möglichen Zusammenhang zwischen den mechanischen Veränderungen des Gewebes und den zugrundeliegenden histologischen Gewebeveränderungen in den unterschiedlichen Krankheitsstadien der EAE, dem Tiermodell der MS. Die hier dargestellten Experimente konnten demonstrieren, dass das ZNS-Gewebe durch zunehmende Zelldichte steifer wird, während es bei fortschreitender Demyelinisierung zur Erweichung des Gewebes kommt. Ferner wurden die mechanischen Gewebeeigenschaften in den unterschiedlichen Krankheitsstadien der EAE durch die Astrogliose und die Mikroglia/Makrophageninfiltration beeinflusst. / Multiple sclerosis is one of the most frequent and significant autoimmune inflammatory diseases in young adults. Although the classic hallmarks of the disease, such as immune cell infiltration, demyelination, gliosis and axonal damage, are known, the causes and underlying pathophysiology remain largely elusive. In recent studies biomechanical changes have already been associated with histological changes in the CNS. However, the correlation between tissue stiffness and the underlying structural changes is currently poorly understood. In this thesis I investigated how tissue stiffness is linked to the underlying structural changes during the different stages of an experimental autoimmune encephalomyelitis mouse model of MS. My data indicate that an increase in cell density leads to an increase in the CNS tissue stiffness, while demyelination reduces tissue stiffness. Furthermore, the mechanical properties were influenced by gliosis and microglia / macrophage infiltration.
75

Multiple attenuation via wavefield transformations.

Lamont, Matthew G. January 1998 (has links)
Seismic multiples are a serious hindrance to hydrocarbon exploration in Australia. In particular, water bottom multiples can be very difficult to attenuate. This is because there often exists a strongly reflective sea floor which gives multiples large amplitudes when compared with the primary events they overlay, and secondly, because of a widely occurring velocity inversion, which seriously reduces the effectiveness of a very important class of multiple attenuation techniques.Multiple attenuation techniques can be classified according to the characteristic of the data which is used to discriminate against the multiples in conjunction with the operation behind the demultiple process. Common multiple attenuation processes include FK demultiple, Radon Demultiple, predictive deconvolution, wave equation based demultiple procedures and the family of techniques which come under the umbrella of Surface Multiple Attenuation (SMA). All of these techniques, given the right conditions, can be very effective. They also vary in price from very cheap (FK demultiple) through to expensive (wave equation based demultiple procedures).However, despite these procedures, and fifty odd years of research, there is no effective general solution to multiple problems off the coast of Western Australia and indeed in many regions around the world.Two new wavefield transformations, Multiple MoveOut (MMO) and IsoStretch Radial Trace (ISR), have been developed in this research to precondition data prior to the removal of surface related multiples by existing techniques. These form the basis of a new multiple attenuating procedure.MMO shifts the data so that the water bottom primary event is flattened and the simple water bottom multiples are also flat and periodic. Water bottom peg leg multiples are made approximately periodic.To solve the stretch problem introduced by the MMO transform, ISR ++ / interpolates oblique traces of constant stretch, which also map constant shot emergence angles. The water bottom primary and multiple events form a stationary time series after MMO and ISR. They are then amenable to removal by autoconvolution and predictive deconvolution.The results of the new procedure are demonstrated on two case studies from offshore Western Australia. It is shown to be more effective at removing both simple and peg leg water bottom multiples than traditional techniques. Finally, it is an inexpensive procedure, which does not require velocity analysis prior to its application.
76

Multiple sclerosis and psychological well-being the role of physical and psychosocial factors

Healy, Christine, Khealy@alphalink.com.au January 2005 (has links)
Multiple sclerosis, (MS), presents affected individuals with an uncertain future, and has broad physical and psychosocial implications for their daily functioning. This study aimed to investigate the psychological well-being of people with MS with an emphasis on positive psychological functioning. It also aimed to extend previous research that suggested reporting perceived benefits during adversity may be indicative of cognitive adaptation. Disease-related variables (mobility, fatigue) and psychosocial factors (optimism, coping) were examined to ascertain the effects of living with MS upon well-being. Well-being was determined using two general measures (The Profile of Mood States (POMS), Shacham, 1983; and the Ryff Psychological Well-being Scale (PWB), Ryff & Keyes, 1995), and Mohr et al.�s (1999) MS psychosocial factors (Demoralization, Deteriorated Relationships, Benefit Finding). Participants were 154 people with MS who were recruited through the MS Societies of Victoria and Tasmania. Results showed participants reported both negative and positive consequences from their MS experiences. Higher levels of Demoralization and Deteriorated Relationships were related to decreased well-being. However, no association was found between Benefit Finding and psychological well-being. Benefit Finding was also unrelated to optimism, and the disease-related variables (mobility, fatigue). Only positive reappraisal coping was predictive of reporting of benefits which lends support to the notion that it is a coping strategy. To examine the effects of mobility the sample was divided into three groups: normal gait, mild gait problems but not using aids and those who require aids for mobility. Significant differences between the mobility groups were found on Demoralization and fatigue levels. As participants� difficulties with mobilisation increased so too did their levels of demoralisation. However, those with mild gait problems reported fatigue levels comparable with those experiencing more complex gait difficulties. No differences were found between the groups on the general psychological measures, which may indicate some form of resilience or psychological adaptation occurring. More generally, results showed that participants who were more optimistic, less fatigued, and used less of particular coping strategies (either less avoidant coping or less blaming self or others) to deal with their MS problems reported higher well-being (less demoralisation, less psychological distress and higher positive functioning). In conclusion, the use of multi-dimensional outcomes enabled a comprehensive examination of well-being and highlighted the effects of specific illness-related factors and coping strategies. As demonstrated in this study, despite the adversity of living with MS, people are able to maintain a healthy sense of self and their relationships, and report benefits from their experiences.
77

Wheat-chickpea yield performance, competition and resource use in intercropping, under rainfed conditions of South Australia / Mohammad Reza Jahansooz.

Jahansooz, Mohammad Reza January 1999 (has links)
Bibliography: p. 203-222. / xi, 222 p. : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The aim of this thesis was to quantify yield performance, competition effects and the capture and utilisation of resources of some important winter cereals and legumes as intercrops. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agronomy and Farming Systems, 2000
78

The molecular mechanisms of arsenic trioxide in multiple myeloma

Cheung, Wai-chung. January 2006 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
79

Turbo-coded OCC-CDMA with spatial diversity for wireless mobile communications

Tjahjadi, Aldo 04 November 2002 (has links)
Turbo codes have been used successfully for error correction in digital communications, however, their application to wireless mobile communications is still a fresh research topic. The objective of this thesis is to present a new solution that involves the usage of turbo codes, spatial diversity, and orthogonal complementary codes in a CDMA spread spectrum system in order to deliver good performance in a fading environment at low signal-to-noise ratios. The results of the research that was performed to write this thesis are presented in a modular and progressive fashion. That is, the design of a basic turbo-coded system in additive white Gaussian noise (AWGN) is developed first in order to get a good understanding of its potential in a wireless communication environment. Then the basic system design is expanded to include fading channel characteristics and multiple access spread spectrum capabilities using classical code division multiple access (CDMA) techniques. Finally, orthogonal complementary codes are used in lieu of traditional spreading codes and spatial diversity is introduced to maximize system performance. / Graduation date: 2003
80

Efficient decision feedback receiver design for cellular CDMA spread spectrum communications

Volz, Patrick U. 07 May 1999 (has links)
This dissertation presents the continued study of a non-iterative decision feedback (DF) receiver/decoder design and its application to cellular communications or wireless local loop systems based on the IS-95(-A) standard of the Telecommunications Industry Association and also Personal Communications Services systems based on the American National Standards Institute standard J-STD- 008-1996, which use code-division multiple access (CDMA) spread spectrum technology. Specifically, the DF decoder presented herein can be used in the uplink of these systems, which simultaneously uses a concatenation of convolutional coding, interleaving, and orthogonal Walsh modulation. The main contributions of this dissertation are the demonstration that the DF concept works well in multipath fading environments, the design of a new time-efficient decoding algorithm, and a new interleaver design. Initially, the performance of the DF decoder is assessed in unfaded as well as Rayleigh fading multipath propagation in additive white Gaussian noise interference. Simulation results using coherent and noncoherent detection are presented for both independent Rayleigh fading and Rayleigh fading with a commonly used Doppler spectrum. The results show improved performance compared to conventional non-DF receivers using the same decoding metric. This is a prerequisite for application of the DF decoder in an actual mobile communications environment. The effectiveness of the initial DF decoder design, as it is applied to IS-95 based systems, is studied. It is found that the effectiveness of the DF decoder is determined by the decoding delay of the convolutional decoder and the interleaver specification. Based on these findings, two methodologies to improve the effectiveness of the DF decoder are investigated. First, the average decoding delay is reduced using sub-optimal convolutional decoding. Second, the combination of a new block interleaver design and the DF decoder is considered. Simulation results of average decoding delay, bit error rate and frame error rate are presented for coherent and noncoherent detection of unfaded and Rayleigh fading multipath signals. It is shown that both approaches result in better system performance, which can further improve the quality of service and/or capacity of an IS-95 based system. Finally, a simplified analysis of the DF decoder performance is presented. / Graduation date: 1999

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