title: Construction and Characterization of Insertion and Deletion Mutations in the Transforming Genes of Human Adenovirus Type 5

contributor:
Graham, Frank Lawson
Biology

subject: Biology Biology

abstract:
The process whereby a normal cell becomes malignant, termed transformation, can be initiated by a number of agents that have been implicated in carcinogenesis. Understanding the mechanism of oncogenic transformation is a necessary prelude to developing a rational approach to therapeutic and preventative treatment of this disease. This thesis examines the molecular mechanism off cell transformation caused by a member of a family of DNA tumor viruses, the human adenoviruses. The experimental approach taken in this work was to use recombinant DNA techniques to isolate the oncogenes encoded in the genome of adenovires serotype 5 (Ad5). Defined mutations were constructed in these Ad5 oncogenes, and mutated plasmids were assayed for their transforming activity on primary rat and on primary hamster kidney cells in order to identify which Ad5 genes were necessary for primary cell transformation.

This study reports the construction and characterization of a library of recombinant bacterial plasmids, containing DNA restriction endonuclease fragments representing the entire Ad5 genome. This library of cloned viral DNA fragments has served as a useful source of reagents for both biological and biochemical studies on the molecular biology of adenovirus.

This study employs the prokaryotic transposable element Tn5 as an insertional mutagen for cloned Ad5 sequences. The results demonstrate the usefulness of bacterial transposable elements for gene mapping experiments with cloned eukaryotic genes. A number of insertion mutations located in the Ad5 oncogenes were constructed and were characterized by DNA sequence analysis as a prelude to studies on their transforming activity. The results of studies on the specificity of target DNA sequences chosen for Tn5 insertion suggest that transposition is influenced by transcriptional activity in target DNA.

The results of morphological transformation experiments with primary rodent cells using plasmids containing the adenovirus oncogenes (early regions E1A and E1B), and with plasmids containing defined insertion and deletion mutations in these oncogenes, have demonstrated the following. First, viral genes located exclusively in the rightward transcribed DNA strand of E1A are essential for transformation. Secondly, the viral gene located in the promoter proximal region of early region E1B, encoding a Mr=21,000 product, is required for transformation. Third, the requirement for this E1B product could be replaced with serum supplements to cells transformed by only region E1A. Finally, it was demonstrated that not all primary cells require two cooperating oncogenes for cell transformation since insertion mutations located in E1A, which eliminate transformation on primary rat kidney cells, did not eliminate transformation on hamster kidney cells.

These results have helped to define the adenovirus genes encoding functions that are essential for cell transformation. Results presented also suggest possible roles for these viral functions in maintaining the transformed state. It will be of considerable interest to determine the biological properties of these gene products which allow them to bring about the process of cell transformation.

abstract: Doctor of Philosophy (PhD)


title: The Perception of Contrast and Color by the Human Newborn

contributor:
Maurer, Daphne
Psychology

subject: Psychology Psychology

abstract:
This thesis investigated newborns' ability to detect contrast and to discriminate chromatic from achromatic stimulation. I studied newborns' sensitivity to contrast by taking advantage of their preference for patterned over unpatterned stimulation. Newborns (n=60) looked longer at checkerboards in which the checks contrasted by 11%, by 17%, by 23% and by 27% than at grey squares matched in mean luminance to the checkerboards, but showed no preference when tested with checks contrasting by 3% or 5%. In addition, the magnitude of their preferences increased as a function of increasing contrast. In order to examine contrast detection developmentally, 2-month-olds (n=24) were exposed to a series of contrasting checkerboards and the respective matching grey squares. The results showed that 2-month-olds demonstrated preferences for checkerboards with contrasts of 5%. of 11%, and of 23% but not of 3% over matching grey squares. However, 2-month-oIds' preferences did not increase with increasing contrast. These results suggest that newborns and 2-month-olds are much more sensitive to contrast than previous studies had indicated.

In studies designed to test color perception, newborns were shown a series of colored-and-grey checkerboard patterns in which the difference in luminance between the color and the grey components was varied across a range centred at the luminance where adults would see the color and the grey as equally bright. It was assumed that with at least one of the patterns, newborns would not detect a brightness difference between the colored-and-grey checks. Therefore, newborns would be abIe to detect such a pattern only if they could detect its hue. In this case, newborns should show a preference for this pattern as well as all other checkerboards over the matched grey squares.

Newborns were shown six green-and-grey (n=60), six yellow-and-grey (n=60), six red-and-grey (n=60) and six blue-and-grey (n=60) checkerboards and the matching grey squares. The results showed that regardless of the difference in luminance between the chromatic and achromatic checks, newborns demonstrated that they differentiated grey from green, from red, and from yellow. However, when viewing blue-and-grey checkerboards, newborns did not show a preference for two of the patterns over their matching grey squares. Secondly, the pattern of newborns' preferences for these blue-and-grey checkerboards over the matched squares was very similar to what it had been when newborns were shown achromatic checkerboards in Experiment 2. This pattern suggests that only contrast information was present when newborns viewed these "blue"-and-grey checkerboards. A subsequent experiment with 1-month-olds revealed that infants at this age were able to differentiate the blue from the grey checks in the checkerboards.

These data constitute the first demonstration of color vision in newborns. They imply that newborns possess at least one functioning cone system and that at least some portion of the geniculostriate pathway may be operational. The data also suggest that there are limitations on newborns' color vision: Newborns appeared not to detect the short-wavelength hue. Moreover, the luminance at which their preference for a blue-and-grey stimulus disappeared is consistent with previous reports that young infants see short-wavelength light as relatively brighter than do adults.

abstract: Doctor of Philosophy (PhD)


title: Characterization of the beta-subunit of the mammalian SRP receptor and its role in assembly of the SRP receptor

contributor:
Andrews, David W.
Biochemistry

subject: Biochemistry Biochemistry

abstract: The eukaryotic signal recognition particle (SRP) receptor is a heterodimeric complex present on the endoplasmic reticulum (ER) membrane, and is required for the targeting and translocation of nascent polypeptide chains across the ER. Both SRP receptor subunits, SRα. and SRβ, are GTP-binding proteins. The role of the SRα subunit in the nascent chain targeting reaction is wen understood, but the function of the SRβ subunit has not been determined. This thesis demonstrates that a complete and functional GTP-binding domain of SRβ is necessary to bind SRα, and that the integrity of the SRα-SRβ dimer is regulated by the SRβ GTPase. Further analysis of SRI3 revealed functional characteristics that are not shared with other GTPases. Most significantly, whereas other GTPases purify in the GDP-bound inactive state, SRβ purified in the GTP-bound active state. Furthermore, SRβ bound specifically to ribosomes, but ribosome-binding did not influence the activity of SRβ. The recently solved structure of the SRα-SRβ complex from yeast allows for the discussion of my results from a structural perspective. The results of this work in combination with the published literature allow me to update the existing model for protein targeting and translocation in higher eukaryotes. In this new model SRβ plays a greater role than previously appreciated.

abstract: Doctor of Philosophy (PhD)


title: Finding Meaning in Adversity

contributor:
Browne, Regina
Nursing

subject: Nursing Nursing

abstract:
Experiencing hardship, suffering and loss and finding a way to learn from one's experiences rather than being overtaken, diminished and embittered by them, constitutes an inevitable human challenge. Yet surprisingly, little has been written about the structure of the experience of adversity. Equally astounding is the fact that although there is considerable knowledge about the personality traits and behavioral patterns of people who are resilient in adversity, little is known bout how people actually construct meaning in such a situation. Part of the reason for this missing knowledge may be the prevailing dominance of quantitative methods in health research. Although these methods are useful for revealing factors associated with positive patterns of adaptation they are less adequate in revealing both the structure of human experience as wen as the practices that humans engage in to make sense of their world.

By describing and analyzing the shared lived experiences of twenty ~five people who have lived through a situation of adversity, as wen as the practices they engaged in to recover meaning, and the meanings they gave to their experience, this hermeneutical phenomenological study uncovers new knowledge related to the structure of adversity. In doing so knowledge is gained about how personal coherence can be preserved under extreme conditions. In particular, the study unfolds the structure of adversity in terms of three key themes - turning, dwelling and caning. In addition, the practices that people engage in as ways of dwelling amidst adversity are discussed. Ways of dwelling are thus compared and contrasted to reveal those that call forth, or alternatively conceal, authentic possibilities in life. In order to clarify the existential and ontological challenges at stake in situations of adversity, the philosophical frameworks ofKierkegaard, Heidegger, Marcel and Gadamer are brought into a converging dialogue with the stories and conversations gathered for this study. Inferences for health professionals in general, and nurses in particular are drawn. These inferences are offered in consideration of the professional commitment to care for people during times when meaning breaks down and when the presence or absence of human solicitude and caring has far reaching implications.

abstract: Doctor of Philosophy (PhD)


title: PROMOTIONAL COMMUNICATION AND REFELIXIVITY: CASE STUDIES IN THE MEDIA POLITICS AND PROBLEMATIZATION OF NEO-LIBERALISM

contributor:
Knight, Graham
Sugiman, Pamela
Wells, Donald
Sociology

subject: Sociology Sociology

abstract: This dissertation offers a critical analysis of the media politics underlying the shift to neo-liberalism. Special attention is paid to the relationships between news media, government and corporate public relations, and social movement activism in the context of changing policy priorities that advance market-based solutions for economic and political challenges. Neo-liberalism is accounted for in terms of both its policy and ideological dimensions, and the study demonstrates that neo-liberal forms of rule contribute to, rather than alleviate, risk and uncertainty. The consequence or 'reflexive effect' of this is a re-politicization of the public sphere and the creation of a space for struggle over the allocation of blame and responsibility for the social harms such policy programmes frequently entail. Such struggles, the study argues, tend to be waged communicatively and in the arena of news media. The research draws on a range of theoretical and methodological approaches to the study of media and politics, obtaining insight from the disciplines of sociology, political science, media studies, management communication and policy studies. Quantitative and qualitative approaches, including content and textual analysis, openended interviews, and various forms of observational analysis (participant and nonparticipant), are used in an effort to explain the various dimensions of neo-liberal rule and resistance. The research demonstrates that media production sites are less closed to the participation and contributions of marginalized sources than critical studies have previously suggested. At the same time, however, asymmetrical power relations imbue both policy and news making, and while alternative actors may be successful in having their voices heard, this is not the same thing as arguing that the media and policy fields are necessarily open to alternative viewpoints. Indeed, in the cases examined here, a liberal market ideology was shown to be predominant, despite the strategies and activities of social movements and occasional failures of elites to control the parameters of policy debate. Empirical evidence for these findings is provided in two case studies, each of which contains a critical news analysis and examination of the PR strategies and positions of key policy participants. The first study interrogates the issue of market-based electricity restructuring in Ontario under the Conservative governments of Mike Harris and Ernie Eves (1995-2002). The second study investigates debates that have occurred over global labour standards in relation to the rise of commodity chain production within the sports footwear and apparel industry and addresses exclusively the anti-sweatshop campaign against Nike.

abstract: Doctor of Philosophy (PhD)


title: Mechanisms of Neocortical Long-Term Potentiation and Long-Term Depression in the Freely Behaving Rat.

contributor:
Racine, R.J.
Psychology

subject: Psychology Psychology

abstract: Long-term potentiation (LTP) and depression (LTD) are activity-dependent changes in synaptic strength that model how the brain might store memories. The mechanisms of LTP and LTD have been studied extensively in the hippocampus because the hippocampus is critical for memory storage. The neocortex is also believed to be critical for the long-term storage of memories, but less work on LTP and LTD has been done in the neocortex. Furthermore, the majority of neocortical LTP and LTD studies have been carried out in artifical brain-slice preparations. The experiments presented in this thesis test some mechanisms of LTP and LTD in the neocortex of the awake, freely behaving rat.

abstract: Doctor of Philosophy (PhD)


title: EFFECT OF FIXTURE DYNAMICS ON THE FACE MILLING PROCESS

contributor:
Elbestawi, Mohamed A.
Mechanical Engineering

subject:
Mechanical Engineering
Mechanical Engineering

abstract: Accurate prediction of dynamic machining forces is essential in order to estimate the product and process quality, tool life and stability of the machining process. To achieve such a goal, all the aspects affecting the machining process dynamics should be considered. An integrated dynamic model that takes into consideration the dynamic effects of different machining process elements on the chip load was developed. This model considers the effect of cutter geometry, cutter initial position errors, spindle tilt, workpiece geometry, machine tool dynamics, and workpiece/fixture system dynamics. The open literature has no information on the effect of fixture dynamics on the chip load and the machining process stability. Proper modeling of the workpiece/fixture contact requires the modeling of the friction conditions because friction forces can be utilized to reduce the number of fixture components, thereby exposing more of the workpiece features to machining operations. Also, it provides a damping mechanism to dissipate input energy from machining forces out of the workpiece/fixture system. The literature lacks research on the tribological aspects of the workpiece/fixture contact. Since many factors influence the coefficient of friction, an experimental investigation was carried out to study the tribological aspects of the workpiece/fixture contact. Based on the findings of this study a velocity limited friction model (VLFM) was incorporated in the finite element analysis of the workpiece/fixture contact. The model utilizes NURBS curves and surfaces for the geometric modeling of the tool cutting edges and the workpiece geometry. A grid based meshing scheme for the finite element analysis was developed based on the NURBS iso curves. An in-house finite element code was developed for the analysis of the workpiece/fixture dynamics. Simulated cutting forces showed good agreement with the experimental validation. Two case studies are presented to demonstrate the practical application of the developed methodology. The integration of all of the above in one model provides an off-line tool to simulate and optimize the machining parameters and the fixture configuration. This cuts production time and cost.

abstract: Doctor of Philosophy (PhD)


title: Short-Term Load Demand Modelling and Forecasting

contributor:
Sinha, Naresh K.
Electrical and Computer Engineering

subject:
Electrical and Computer Engineering
Electrical and Computer Engineering

abstract:
The major effort in this thesis has been directed towards the problem of short-term load demand forecasting. Special attention has been given to on-line load forecasting of several loading nodes simultaneously. A critical review of the state of the art in short-term load forecasting methods is presented. A new approach has been used to classify these methods according to the modelling approaches used for representing the load demand.

Two multivariable, autoregressive and state space, models simultaneously have been proposed. The order of the autoregressive model is obtained without fitting coefficients to different models. Based on multivariable state space representation an efficient and completely automatic algorithm for on-line load forecasting is proposed. It has been shown that by utilizing the innovations representation an ordinary recursive least-square algorithm can be used to give unbiased estimates of the model parameters. The proposed algorithms obtain good forecasts even in case of loss of observations from one or more nodes.

To obtain load forecasts for one-weak-ahead, the total load is divided into three components: nominal, weather sensitive, and stochastic. A special approach has been proposed to identify the weather-sensitive load component. Also, a study has been carried out to identify those weather variables which have a significant effect on the load demand.

Actual load data from Ontario Hydro has been used to test the proposed methods.

abstract: Doctor of Philosophy (PhD)


title: Phenylhydrides of the Groups 4B and 5B Elements and Their Monoanions

contributor:
Birchall, T.
Chemistry

subject: Chemistry Chemistry

abstract:
¹H, ¹³C and, where appropriate, ³¹P NHR spectra for the series of compounds (C₆H₅)nXH₃_n and (C₆H₅)nXH₂_nNa (n = 1, 2; X = N, P or As), have been recorded and assigned. The results are consistent with the existence of a pπ-pπ interaction between substituent and phenyl ring in all cases when the atom is nitrogen but only in the anions when the substituent atom is phosphorus or arsenic. ¹³C NMR spectra of the compounds (C₆H₅)nGeH₄_n and (C₆H₅)nGeH₃_nNa as well as (p-CH₃C₆H₄)₃GeM (M = H, Na) have also been recorded and assigned. Comparison of the chemical shifts demonstrated that the extent of delocalization of the negative charge is significantly less in the phenylgermyl anions than in the analogous group 5B species. This corroborates the observed differences in the effect of phenyl-substitution on the acidities of main group hydrides as rationalized in terms of hybridization at the anionic centre and subsequent degree of resonance delocalization.

The distribution of π-electrons in the mono-substituted benzenes, whose substituents are anionic centres, appears to be the result of the balance between mesomeric and electric field effects. The latter effect produces a polarization of the phenyl ring dependent upon the extent to which the negative charge is localized on the substituent atom. The magnitudes of these effects depend somewhat on the extent and nature of solute-solvent interaction, ion-pairing and association in the solutions of these salts which, in turn, are a function of the polarity of the solvent.

Adduct formation between cuprous iodide and both PH₃ and C₆H₅PH₂ was investigated. Comparison with literature results for complexes of (C₆H₅)₂PH, P(C₆H₅)₃ or other tertiary phosphines indicates that σ-donor strength alone, as opposed to π-acidity or steric bulk, is the dominant factor influencing the stability of the coordinative interactions of the smaller phosphines. The structure of the complex [CuI(C₆H₅PH₂)₂]₂ is reported. ¹²⁷I Mössbauer spectroscopy was found to be incapable of discriminating between different iodine environments in such complexes.

abstract: Doctor of Philosophy (PhD)


title: The Mechanism of Organic Removal During Coagulation

contributor:
Benedek, Andrew
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract:
Coagulation is a common water treatment step primarily designed to aggregate and thereby help remove true particulate (turbidity causing) matter. Organic compounds of natural origin (i.e. humic and fulvic acids) have also been observed to be removed by Coagulation. This research was designed primarily to identify the limiting mechanisms responsible for the removal of natural organics by the coagulation process. This identification is thought to be crucial in the optimization of this important water treatment step as it may help to maximize the benefits obtained from coagulants.

The examination of the literature related to this topic suggests two possible removal routes:

(i) a reaction whereby the fulvic acids form an original compound with the coagulating ion Al³⁺ or one of its hydroxy complexes.

(ii) the adsorption of the fulvic acid molecules or jons onto the surface of a solid precipitating independently of these compounds.

These two possibilities are examined in detail on theoretical grounds, and two following pieces of information are defined as being discriminatory with respect to the two removal routes:

(i) The shape of the isotherm, as defined in typical adsorption studies.

(ii) The ligand number or OH/Al ratio of the precipitate, accessible by processing the dissolved Aluminum data with respect to pH.

These considerations lead to an experimental design allowing the convenient evaluation of these characteristics. An array of nine treatment dosages and four operating pH is applied on two raw waters, using four Aluminum based coagulants.

The results suggest that under these experimental conditions (dosage between .1 and 1 mM Al/L pH between 5 and 8.5), the Fulvic acids are removed by Adsorption onto Al(OH)₃, regardless of the type of coagulant. Increasing pH and the presence of SuIfate in the coagulant were found detrimental to this adsorption. Increasing OH/Al ratio in the coagulant is detrimental at low pH, low dosage, and becomes beneficial at neutral to mildly alkaline pH conditions. A two stage treatment scheme was found efficient at neutral to mildly alkaline pH, using Alum.

abstract: Doctor of Philosophy (PhD)


title: Some Problems in the Crystal Chemistry of Platinum Complexes

contributor:
Lock, C. J.
Chemistry

subject: Chemistry Chemistry

abstract:
Molecular and crystal structure studies related to various aspects of the chemistry and biochemistry of platinum are presented. The first terminal Pt(II)-OH₂ bond observed in-a single crystal verifies the existence of a stable, four-coordinate aquaplatinum(II) complex. The Pt-OH₂ bond is normal and the cis-i Pt (OH₂) (NH₃)₃ (1-methylcytosine)]²⁺ ion models a proposed initial monofunctional Pt-DNA complex. The molecular structure of trans-[Pt(NO₃)₂(NH₃)₂ in the solid state is shown to be similar to the cis isomer in that it has two monodentate nitrato ligands, but it differs in that the non-bonded oxygen atoms of the two nitrato ligands lie above and below the ligand square plane. Evidence is presented for ionic and tetravalent platinum impurities in freshly prepared solutions of trans-[PtCl₂(NH₃)₂]. The structure of trans-[Pt(NH₃)₂(1-methylcytosine) (9-ethylguanine)]²⁺ offers a possible model for DNA interstrand crosslinking which can explain the thermal stabilization of DNA (with the preservation of base stacking) observed after exposure to low concentrations of trans-[PtCl₂(NH₃)₂.

Various problems of crystallographic interest are discussed. The geometry of diethylenetriamine complexes in the solid state is examined, and a convention is proposed for assigning conformations. A survey of dien complexes is used to emphasize the importance of intermolecular hydrogenbonding, as opposed to intramolecular steric interactions, in the configuration of the dien ligand. Various types of disorder in linear chain halogen-bridged mixed-valence platinum compounds are examined. An unusual example of a Pt(II)...Cl-Pt(IV)-Cl chain compound with three-dimensional ordering at the Pt(II) site is presented. The importance of weak intensity data and careful photographic work in these systems is also demonstrated.

The structural analyses of aqua, nitrato, and ammine nitrate complexes are aided by the use of the bond valence model. Quantitative bond length and qualitative packing predictions are made, and structural anomalies are explained, using empirical bond valence curves.

abstract: Doctor of Philosophy (PhD)


title: Preconcentration of Trace Metal Ions from Natural Waters: Studies on the Application of an Acrylic Ester Macroreticular Resin

contributor:
Corsini, A.
Chemistry

subject: Chemistry Chemistry

abstract:
A new preconcentration method has been developed for the determination of trace metals from natural waters. The method is based on the direct uptake of metal ions on a column packed with the macroporous acrylic ester resin, XAD-7, after interfering humic substances are removed on a XAD-7 precolumn. The retained metal ions are subsequently eluted with 1% v/v HNO₃ and the trace metals determined by graphite-furnace atomic absorption spectroscopy. The effects of various parameters such as pH, ionic strength, anions, organic substances, flow rate, column bed-size and resin particle size on the adsorption and elution of metal ions were examined. Based on these investigations, optimal conditions for the group preconcentration of Cr, Fe, Cd, Co, Cu, Mn, Ni and Pb were established.

The method was successfully applied to various natural waters and was found to be simpler and less susceptible to contamination than the Chelex-100 method. In addition, a larger preconcentration factor was obtained. The accuracy and precision of the XAD-7 method were found to be at least competitive with the Chelex-100 method.

The mechanism of adsorption was investigated and adsorption isotherms and distribution ratios of selected metal ions were measured. The adsorption process is complex and likely involves charge-dipole interactions.

A simple model was developed to illustrate the rationale of the method of standard additions in a preconcentration procedure. It was shown that a high degree of spike reaction with the sample matrix and a reasonable degree of analyte separation are vital for the successful application of standard additions. If the degree of separation is very high, the method of standard additions is not required and only a simple calibration curve is necessary.

abstract: Doctor of Philosophy (PhD)


title: New Horizons in Computer-Aided Design of Sheet Metal Stampings

contributor:
Sowerby, R.
Mechanical Engineering

abstract:
The determination of principal finite strains from measurements made on a pair of deformed line elements is discussed. The deformation process is assumed to be either homogeneous or pure homogeneous in nature. Emphasis is placed on the pure homogenous mode since it leads to a simpler finite strain tensor and this technique is applied to determine the strain over the surface of an industrial stamping. The present work draws the distinction between homogeneous and pure homogeneous deformation. In the latter mode, an orthogonal triad can be identified (the principal axes), which remains orogonal throughout the deformation. An appropriate strain measure in such processes is that of logarithmic strain. Furthermore, its material derivative equals the rate of deformation tensor. Such a simple expression does not hold when the deformation gradient tensor is nonsymmetric, as in homogeneous processes.

The material derivative of the tensor logarithm is no longer simply related to the rate of deformation tensor, and this is exemplified herein. The resulting expression involves the spin of the triad of the Eulerian and Lagrangian ellipsoids.

Stress components vary as a result of material rotation and constitutive equations whereby rotational effect of material has been accounted for must be formulated. In finite deformation various "rotation" tensors can be defined. Consequently a wide choice of objective stress rates is available for adoption in constitutive equations, and a number of objective stress rates are examined herein. The utility of the resulting expressions is demonstrated for the case of a hypoelastic material undergoing finite deformation in simple (rectilinear) shear.

Another aspect of this work has been an attempt to establish an approximate computer-aided technique for blank development, referred to as Geometric Modelling, and the investigation of possible strain distributions in forming sheet metal components. The technique is based on the initial assumption (this can be refined at a later stage) that a sheet metal component is transformed from a fiat sheet into a non-developable surface without change in thickness. Although few practical forming process occur in this way, many traditional die design procedures are based on similar notions; either there is no change in surface area or that a line length on the undeformed blank is unchanged during forming. Simple plasticity theory also suggests that the membrane stresses in a sheet would be minimized (in the absence of a normal stress) if no change in thickness occurred, therefore given the opportunity, the deformation is likely to take place in this ideal manner. The method of geometric modelling simulates the traditional manual calculations performed by experienced tool designers. The technique does not aim to replace the skill and experience of the designers but rather to enhance them.

The present work describes the formulation of the fundamental theories of the method which comprise of the element-by-element mapping and remapping procedures and techniques of surface adjustment. The basic geometric assumptions employed in the development are also described. Two particular automotive stampings have been considered; one is the corner section of a car seat panel and the other is an inner deck-lid of a mid-size vehicle.

A computer-aided design package for tool/die designers has been developed and the detailed analytical procedure is implemented in Fortran code. The analysis has been performed without access to advanced computer graphics. However, it is carried out in a way that future modelling using interactive computer graphics may well be attainable.

abstract: Doctor of Philosophy (PhD)


title: Narration and Life History of a Newfoundland Woman

contributor:
Preston, Richard
Anthropology

subject: Anthropology Anthropology

abstract: The deficiency of analysis and interpretation has been expressed as a persistent concern in the use of life history material in anthropology. An explicit focus on its usage as an illustrative, heuristic device in the explanation of the culture concept continues to be emphasized. Subsequent attempts at interpretation highlight a prevalent assumption that views the individual and culture as dichotomous entities. This thesis rejects a dichotomous stance as an underlying assumption in the design of a frame of reference for interpreting the life history of Ruth Ollerhead. Instead, the emphasis shifts into an interpretation which attempts to view culture and the individual simultaneously. In addition, this emphasis highlights a comprehension which leads to bringing the text from unintelligibility to an understanding of the individual qua individual. Therefore, a hermeneutical position operating within a phenomenological perspective is used in providing an orientation for a focus which remains grounded in the textual data and calls for acquiring understanding rather than an explication of the text. Viewing the individual and culture simultaneously within this frame of reference requires that three levels of conceptualization--i.e., the immediate contextual framework of the ethnographic situation, the interplay between the individual and her culture and the larger socio-cultural context--must be known to comprehend fully the contextual meaning of events and experiences described in the life history.

abstract: Master of Arts (MA)


title: Mixed Polyatomic Cations of Sulfur, Selenium and Tellurium

contributor:
Gillespie, R.J.
Chemistry

subject: Chemistry Chemistry

abstract:
The study of the behavior of the chalcogen elements sulfur, selenium and tellurium with the strong Lewis acids SbF₅ and AsF₅ in SO₂ solution has been continued. A large number of new salts of polyatomic cations of the chalcogens have been prepared and characterized by their X-ray crystal structures, namely (Te₂Se₈) (AsF₆)₂, (Te₄.₅Se₅.₅) (AsF₆)₂, (Te₂Se₆) (Te₂Se₈) (ȦsF₆)₄ (SO₂)₂, (Te₆)(Se₈)(AsF₆)₆(SO₂), (Te₂Se₄)(SbF₆)₂, (Te₂.₇Se₃.₃) (SbF₆)₂, (Te₃.₄Se₂.₆) (SbF₆)₂, (Te₂Se₄) (Sb₃F₁₄) (SbF₆), (Te₂.₁Se₃.₉) (SbF₆)₂ and (S₃.₀Se₁.₀)₂ (Sb₄F₁₇) (SbF₆)₃. Many of the cations in these compounds, those with non-integral subscripts, possess occupational disorder with some or all of the cation sites partially occupied by two different chalcogen elements. The previously known, but incompletely characterized compounds (Te₂Se₂) (Sb₃F₁₄) (SbF₆) and (Te₃.₀Se₁.₀) (Sb₃F₁₄) (SbF₆) and reprepared from stoichiometric reactions and their compositions confirmed by ⁷⁷Se and ¹²⁵Te NMR spectroscopy and X-ray crystallography. The new compounds (Te₃S₃) (SbF₆)₂, (Te₂Se₈) (SbF₆)₂ and (Te₂Se₈) (SbF₆)₂ (SO₂) were prepared and were found to be isomorphous with their hexafluoroarsenate analogues. The new Te₂Se₆²⁺ cation, which co-crystallizes with Te₂Se₈²⁺ in the compound (Te₂Se₆) (Te₂Se₈) (AsF₆)₄ (SO₂)₂, has a novel cube-like structure, which is very different from that of S₈²⁺ and Se₈²⁺, the known homopolyatomic cations of the same average oxidation state. The Te₂Se₆²⁺ structure is compared with the structures of the other polyatomic cations and with the P₁₁³⁻ and As₁₁³⁻ anions. Selenium-77 and ¹²⁵Te NMR studies indicate that the Te₂Se₆²⁺ and Se₈²⁺ cations retain their structures in solution. The spectra for a Te₂Se₆²⁺ sample enriched to 77.3% in ¹²⁵Te are dominate by AA'X and AA'XX' satellite subspectra. The compound (S₃.₀Se₁.₀)₂ (Sb₄F₁₇) (SbF₆)₃ provides the first example of a mixed Se-S cation as well as the only example of the mixed-valence, Sb(III)-Sb(V), Sb₄F₁₇⁻ anion. The orientations of secondary bonds to Sb(III) atoms in the Sb₄F₁₇⁻ and Sb₃F₁₄⁻ anions and to divalent and trivalent chalcogen atoms of the cations are described. These secondary bonds form in directions that cap faces or bridge edges of polyhedra defined by the primary bonds and lone pairs of electrons. Unit cell volumes for the known structures of the polyatomic cations are compared to determine effective volumes for the AsF₆⁻, SbF₆⁻ and Sb₃F₁₄⁻ anions and the S, Se and Te atoms. These volumes have some predictive value in determining the composition of unknown compounds of known cell volume. Selenium-77 and ¹²⁵Te NMR data are presented for many of the cations, including spin-lattice relaxation time (T₁) measurements for the SᵪSe₄_ᵪ²⁺ cations.

Several new salts of MX₃⁺ cations (M = S, Se, Te; X = F, Cl, Br, I) were prepared and crystal structures were determined for the compounds (TeCl₃) (AlCl₄) - triclinic, (TeCl₃) (AsF₆), (TeCl₃) (SbF₆) and (TeF₃)₂(SO₄). The geometries of these and other MX₃⁺ cations are compared with each other and with the isoelectronic neutral molecules. Trends are explained in term of VSEPR arguments and the strengths of anion-cation interactions (secondary bonds). The ¹⁹F, ⁷⁷Se and ¹²⁵Te NMR spectra of the SeF₃⁺ and TeF₃⁺, cations were recorded and the reduced density M-F coupling constants compared and related to the probable geometries of the cations in solution.

Solutions of the mixed F/OTeF₅ compounds TeFᵪ(OTeF₅)₄_ᵪ and [TeFᵪ (OTeF₅)₃_ᵪ]⁺[AsFy (OTeF₅)₆_y]⁻ were prepared and characterized by ¹²⁵Te NMR spectroscopy. Trends in the ¹⁹F-¹²⁵Te(IV), ¹⁹F-¹²⁵Te(VI) and ¹²⁵Te(IV)-¹²⁵Te(VI) scalar spin-spin coupling constants are explained in terms of the greater ionic character of the Te--F bond compared to the Te--OTeF₅ bond. The As(OTeF₅)₆- anion was of sufficiently high symmetry for ⁷⁵As NMR spectra to be recorded in CH₃CN and SO₂ solvents. The activation energy for Berry pseudorotation in Te(OTeF₅)₄ was determined from variable temperature ¹⁹F and ¹²⁵Te NMR measurements.

abstract: Doctor of Philosophy (PhD)


title: Industrial Sectors and the Determinants of Earnings: Male-Female Differences

contributor:
Pineo, P. C.
Robb, A. L.
Jones, C.
Sociology

subject: Sociology Sociology

abstract: Empirical studies confirm the existence of a male-female earnings differential in Canada, with females on the average receiving about half the earnings that males do. This dissertation attempts to the data used are from develop the most thorough and systematic model of earnings determination yet achieved in Canada, and to investigate the potential utility of a segmented economy approach to identify sources of male-female earnings inequalities. The earnings determination model includes individual earnings-related characteristics, background characteristics, and a measure of the industrial sector of the economy. The data used are from the 1973 Canadian Mobility Study and the Labour Force Survey. Findings indicate that women who are employed receive so little compared to men partly because they differ in the average levels of their income-related characteristics and partly because they differ in the processes by which they earn income. Of the two factors, however, the second is by far the most important source of income inequality between the sexes. When the economy is viewed as composed of three distinct economic sectors the core, the periphery and the state, the three sectors do appear to differ in the ways in which certain earnings-related characteristics are remunerated. Further, it appears as if the differences between men and women in their economic returns are not the same from sector to sector. The findings support two general conclusions in this regard. First, differences in returns for men and women are more frequent in the periphery than in either the core or state. Second, while still distinct, the processes by which men and women earn income are more similar in the state than in either the core or the periphery. In the state, men and women receive nearly equivalent economic returns to their human capital factors, such as education and experience, while this is not the case in the other two sectors.

abstract: Doctor of Philosophy (PhD)


title: PQCT MEASUREMENTS OF BONE MASS, DENSITY, GEOMETRY AND STRUCTURE AT THE DISTAL RADIUS: PREDICTION OF BONE STRENGTH, AND THE IN VIVO EFFECTS OF PHARMACOLOGICAL TREATMENTS FOR OSTEOPOROSIS

contributor:
Webber, Colin E.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract: This work encompasses two primary studies utilizing peripheral quantitative computed tomography (PQCT) in the assessment of bone characteristics at the distal radius. PQCT enables separate analyses of cortical, trabecular and total bone density, content and geometry. Further analysis of the pQCT image with specialized software permits in vivo trabecular structure assessment. The first study is a two-year prospective trial evaluating the effects of five different medication regimens (hormone replacement therapy (HRT), etidronate , alendronate, etidronate plus HRT and alendronate plus HRT) used for the treatment of osteoporosis in 123 postmenopausal women with low bone mass. Results of analyses on baseline data found that trabecular structure indices could significantly discriminate between osteoporotic and osteopenic groups of women. Longitudinal data at the lumbar spine (LS) and femoral neck (FN) for women taking any medication ('Any-Tx') showed similar results to those of large clinical trials. For example, the 'Any-Tx' group gained significant bone mineral density (BMD) over baseline at 2 years at the LS (5.5%, p<0.001) and FN (1.6%, p<0.05). Women on combination therapy gained significantly more BMD than women taking one medication over 2 years at the LS and FN. Data suggests that alendronate plus HRT may produce the largest BMD gains at the LS and FN at 2 years. Longitudinal pQCT data for total, cortical and trabecular compartments at the distal radius in the control group over the 2 years suggest endocortical resorption and trabecular thinning with age. PQCT data in the 'Any-Tx' group show gains in total and cortical bone density and cortical content, but losses in trabecular density, content and area. This suggests that anti-resorptive medications promote endocoritcal apposition and reduce intracortical porosity. The second study evaluated five different clinical measurement tools in the prediction of in vitro failure load at the distal radius and found that cortical content measured by pQCT was a significantly better predictor than ultrasound or digital x-ray radiogrammetry.

abstract: Doctor of Philosophy (PhD)


title: Romantic Hospitality: Theorizing the Welcome in Rousseau, Kant, Coleridge, and Mary Shelley

contributor:
Clark, David L.
English

subject:
English Language and Literature
English Language and Literature

abstract: If hospitality is, as it is for Jacques Derrida, the sign ofthe subject's absolute unpreparedness for and disruption by the sudden appearance and arrival of difference, then what can be said about the theme of the hospitable during a period of English and European culture which is as unsettled (and, indeed, as quickened) by revolution and rapid change as the late eighteenth and early nineteenth century? A theoretical nodal point of increasing anxiety in this age of political and international uncertainty, the category of "the stranger," I argue, points less to the existence of actual alterities beyond the consciousness of the Romantic "subject" than it does to an internal difference which constitutes that subject's own self-dividedness. Drawing largely from Derrida's recent work on figures of hospitality, cosmopolitanism, and forgiveness, and from Judith Butler's theories of subject formation, this dissertation investigates how Romantic figures for the stranger come to operate as normative phantasms whose function is precisely to ground and "naturalize" the repudiative discourses by which the Romantic subject produces and sustains its own self-sovereignty-its mastery over the house of the self. Yet because the process by which "proper" hosts and guests are parsed operates as a regulatory practice based on repetition and exclusion, I argue that the texts of Romantic hospitality are invariably haunted by the very strangers that they deny. Relegated to an unintelligible domain just beyond or "outside" the space of the welcome, these othered spirits return to the site of their disavowal only to reassert their constitutive priority in the hospitable imaginaries of these texts. This dissertation therefore claims that certain writers of the late eighteenth and early nineteenth century (specifically Rousseau, Kant, Coleridge, and Mary Shelley) theorize thejailure of the hospitable relation from a suspicion that, after all is said and done, hospitality is itself structurally impossible. In other words, I contend that for these writers absolute or unconditional hospitality must ruin itself precisely by welcoming its opposite-hostility. What intrigues me about Romantic hospitality is, finally, the fact that while this particular form of discourse founds the sovereignty of the subject through the force of exclusion, it also produces the "stranger" as an inexhaustible site of resistance and reproduction.

abstract: Doctor of Philosophy (PhD)


title: To Keep Close: Mothering Amidst Serious Mental Illness and Suffering

contributor:
Tompkins, Catherine
Nursing

subject: Nursing Nursing

abstract: The desire to mother in women with serious mental illness (SMI) is increasingly recognized by health care professionals. For women with SMI, mothering is often framed as a pathological problem needing a professional response. However, no research could be found concerning the subjective meaning of mothering for women with SMI. This grounded theory study sough to explore how a group of 20 mothers with SMI managed mothering. To Keep Close, a theoretical model, emerged to describe the mothers' efforts to have meaningful relationships with their children in the context of SMI and suffering. To keep close to their children equated to being "normal", "secure" and "responsible" for them. To keep close, they chose strategies that would imitate ideal representations of mother. These strategies included masking, censoring speech and doing motherwork, each intended to make illness invisible. Mothers made choices concerning how they presented self-as-mother and the extent to which the revealed their true identity. However, mothering in illness and suffering became a vortex of contradictions, resulting in their "hitting bottom". They typically sought help from professionals as the last possibility for reconciliation. With such professional guidance, they hoped to return to their values place as mother. In illness and suffering their agency was undermined. These mothers shifted ways of understanding suffering to include their loss of agency in relation to their children. This study's findings demonstrate that the context of mothering is beyond signs and symptoms of mental illness. These mothers emphasized that the biomedical entity did little to represent their mothering realities. To help them reconcile self-as-mother, nurses must acknowledge their difference and the importance of their strategies of invisibility in order to create mothering possibilities sensitive to their situation. It is important to repeat this study with other mothers in difference for theoretical modification.

abstract: Doctor of Philosophy (PhD)


title: DATA FUSION AND FILTERING FOR TARGET TRACKING AND IDENTIFICATION

contributor:
Luo, Zhi-Quan (Tom)
Wong, K. M.
Bosse, Eloi
Electrical and Computer Engineering

abstract: This thesis explores two problems in target tracking and identification: (1) robust track state filtering, and (2) decision-level identity fusion. In the first part of the thesis, a novel finite-horizon, discrete-time, time-varying state estimation method based on on the robust semidefinite programming technique is proposed. The proposed method is robust to norm bounded parameter uncertainties in the system model as well as to uncertainties in the noise statistics. The robust performance of the proposed method is achieved by minimizing an upper bound on the worst case variance of the estimation error for all admissible systems. In the second part of the thesis, two decision-level identity fusion models are proposed: Similar Sensor Fusion (SSF) model and Dissimilar Sensor Fusion (DSF) model. In the SSF model, sensors provide reports on a set of common characteristics of a target, and the fusion objective is to find a fusion result which is most consistent with all the sensor reports. In comparison, sensors in the DSF model explore different characteristics of a target. Their reports are fused in a manner that leads to decreased uncertainty on teh arget identity. In other words, these reports reinforce each other to generate increased certainty on the target identity, rather than being averaged to minimize inconsistency. Furthermore, we propose several fundamental principles for identity fusion, based on which all existing and future identity fusion methods can be evaluated and compared. For the SSF model, two fusion methods are proposed: Convex quadratic fusion method and K-L fusion method. In the first method, inconsistencies between the fusion result and the sensor reports are measured by quadratic functions, and the problem is formulated as a convex quadratic programming problem. In the second method, Kullback-Leiber distance is used to measure the inconsistencies among the probabilistic sensor reports. The resulting formulation leads to a generalized analytic center problem. For the DSF model, we use a special objective function in the optimization formulation to accumulate the physical characteristics on a target explored by each sensor. The resulting fusion method involves solving an analytic center problem. Compared with the two classical decision-level identity fusion methods: Bayesian inference method and Dempster-Shafer evidential inference method, the three new fusion methods require no a priori information on the target, and enjoy small computation complexity. In addition, we show that the three new fusion methods, as well as the two classical methods, all satisfy the fundamental principles for identity fusion. The performance of the proposed fusion methods are illustrated in several numerical examples.

abstract: Doctor of Philosophy (PhD)


title: The Role of c-Src in c-ErbB2/Neu and Estrogen Receptor Signaling: Implications in Transformation and Mammary Gland Development

contributor:
Muller, William J.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract: Breast cancer research has focused on a number of key molecular events suspected to play critical roles in the establishment and progression of the human disease. For example, the c-ErbB2 receptor is amplified or overexpressed in approximately 30% of all human breast cancer cases, its overexpression inversely correlating with a positive patient prognosis. In addition, the estrogen receptor is a key marker in assessing patient prognosis, the progression of the disease state, and is by far the most utilized target to treat breast cancer with approximately 100 million hours of clinical experience with the antiestrogen, Tamoxifen. While these two receptor systems play critical roles in breast cancer progression, the activation of downstream signaling pathways and its consequences on cellular function are unclear. Interestingly, the c-Src tyrosine kinase has been identified to play a role in the modulation of both the c-ErbB2/Neu and the estrogen receptor. Here I will describe a role for c-Src in modulating c-ErbB2/Neu receptor activation and its associated ability to transform at the molecular level, as well as a role for c-Src in estrogen receptor mediated mammary gland development. Significantly, the association of c-Src to the c-ErbB2/Neu receptor plays an important role in the direct and specific activation of the receptor. Furthermore, the loss of c-Src within the mammary gland negatively impact its development, this delay being mediated via the estrogen receptor. Taken together, these studies demonstrate the importance of c-Src in two receptor systems that have been heavily implicated in development and disease, the estrogen receptor and the c-ErbB2/Neu. In both cases, c-Src plays a critical role in receptor activation, coordinating downstream events impinging on reproductive development and in mammary gland transformation. The understanding of the molecular crosstalk between these receptor systems within the mammary gland may provide insight into potential translational therapies in clinical research.

abstract: Doctor of Philosophy (PhD)


title: Human Locomotion: Techniques for Processing and Analysis of EMG Data

contributor:
Bruin, H. de
Kitai, R.
Electrical Engineering

subject:
Electrical and Electronics
Electrical and Electronics

abstract:
Several techniques used by researchers in the area of human locomotion to process and analyse normal and pathological gait electromyographs (EMG) are discussed. Basic elements of neuromuscular organization are described.

The thesis reports original work in several topic. The spectral analysis of dynamic EMG acquired during the locomotion of a normal subject was done to confirm the selected sampling frequency, and to determine a suitable low pass filter cutoff for smoothing EMG prior to data analysis.

Results of using two filters for smoothing EMG, a second order Butterworth low pass filter, and a mid-point moving window average filter are compared.

The cross correlation function is used in analysing EMG, since EMG signals are random. The results of cross correlation are compared with clinical observations in assessing the state of a patient following a stroke. Results for five normal and fourteen hemiplegic subjects are reported.

The conclusion is that cross correlation analysis quantifies the state of the patient and assesses post stroke recovery according to the neurological picture of central nervous system control.

abstract: Master of Engineering (ME)


title: Reducing and Revisioning The Body: Women's Experiences of Weight Loss Surgery

contributor:
Lenton, Rhonda L.
Sociology

subject: Sociology Sociology

abstract: This dissertation examines the experience of 30 women, 15 Canadians and 15 Americans, who have undergone bariatric (weight loss) surgery. Bariatric surgery is reserved for morbidly obese persons; that is, those who weigh more than twice their ideal weight. An integrated model of the insights from stigma and feminist theory is used as the conceptual framework of the study. In semi-structured, in-depth interviews following the format of a life review, the participants discussed the wide-ranging effects of morbid obesity on their lives. My participants' weight negatively affected their family relationships, romantic relationships, and employment prospects. Their weight also had a negative impact on their health and self-image. Dieting and other weight loss strategies proved to be futile. The decision to undergo surgery was not taken lightly, and the majority of the sample maintained they underwent surgery to resolve medical problems and to increase their quality of life. Twenty of the participants had a succesful surgery, although most did not attain a normative weight. The remaining 10, however, experienced massive weight rgain or suffered such severe complications that the procedure had to be reversed. The women whose surgeries were successful reported that weight loss had a dramatic, positive impact on their lives, health and identities. This subgroup discovered a new relationship between the postoperative body and the self, a process that 1 describe as re-embodiment. The majority of the women whose surgeries failed became empowered through self-acceptance and the influence of the size acceptance movement. These women have also constructed a new relationship between the body and the self, and I refer to this process as re-selvement. Interestingly, the stigma of obesity is a greatly diminished factor in the postoperative lives of both sub-groups. I argue that the satisfaction of the surgical successes neutralizes the effects of stigma. The women whose surgeries failed but who have become self-accepting neutralize stigma by challenging their devalued status. This dissertation contributes to knowledge by adding to the sparse literature on the subjective experiences of obese people. My research yields insights into the complexities involved when the body undergoes a dramatic transformation.

abstract: Doctor of Philosophy (PhD)


title: Lives of Rural Women After Myocardial Infarction: A Critical Ethnography

contributor:
Rideout, Elizabeth
Nursing

subject: Nursing Nursing

abstract: This study examined how rurality influenced the lives of twelve women who survived a myocardial infarction (MI). Using a critical ethnographic approach, in-depth interviews with women from southwestern Ontario were analyzed to uncover the ways in which social, political, and cultural forces associated with rurality, influenced women's choices, challenges and experiences post-MI. Women were encourages to filter their post-MI experiences through their "rural lens", to explicate their rural lives, and to reflect on the forces that shaped post-MI events and perceptions. Participant observation and interviews with nurses and physicians who provided post-MI care to rural women were also utilized to explore overt and covert influences in women's recovery. Data analysis revealed four narrative themes. Reticence was evident in the tendences of women to minimize articulation of their worries and to accept the course of their post-MI lives with few questions. Referral Games characterized the crucial role rural physicians played in strategizing to help women access specialty diagnostic and treatment in urban referral centers that were unavailable in rural communities. Resourcefulness was displayed by women in response to meeting their own needs for managing their recovery, so they did not have to depend on others, or if system resources were unavailable. Women placed great value on the support and advocacy they perceived in Relationships with rural health professionals and institutions, and viewed themselves as lucky to live in communities were such connections could be made. The strength of the rurality influence(s) on the narrative themes could not be concluded. Women perceived themselves as different from urban women however, some findings supported existing post-MI literature based on urban populations and previously identified rural health issues. Findings support the inclusion of rural people in policy and resource planning and supporting best practices of rural health professionals on whom women rely.

abstract: Doctor of Philosophy (Medical Science)


title: Defining The Advaned Practice Nursing Role in Advanced Prostate Cancer: Application of a Systematic Patient-Focused Approach

contributor:
Browne, Gina B.
Nursing

subject: Nursing Nursing

abstract: Defining the Advanced Practice Nursing (APN) Role in Advanced Prostate Cancer: Application of a Systematic Patient-Focused Approach Purpose To identify priorities for defining an APN role in advanced prostate cancer. The principles of participatory action research and knowledge of APN were used to adapt two role implementation frameworks to provide a patient-focused approach to role development. Two studies were conducted, the first to examine health related quality of life (HRQL) and health problems across a continuum of prostate cancer care; and the second to examine the prevalence and impact of mental health disorders on HRQL and health care costs. Patients and Methods Study one involved five groups of patients with prostate cancer receiving care at a comprehensive cancer centre including: Early Stage Newly Diagnosed (E-NEW), Early Stage On Treatment (E-RX), Early Stage Receiving Follow-Up (E-FLP), Advanced Hormone Sensitive (A-HS), and Advanced Hormone Refractory (A-HR). 631 patients attending clinic appointments were approached and 551 (87%) participated in the study. HRQL was examined using the Functional Assessment of Cancer Therapy-Prostate scale. Patients identified priority health needs using a checklist of possible health problems. Regression analysis was used to identify patient characteristics that predicted HRQL. A sample of 99 consecutive patients with advanced prostate cancer at the same centre participated in Study two. Participants completed a questionnaire assessing mental health disorders, HRQL, and health costs through a telephone interview. Results A-HS patients experienced HRQL and health problems similar to patients with early stage disease. A-HR patients had significantly poorer HRQL (p<0.001), more severe health problems, and different priority needs compared to other groups. In addition to urinary and sexual function, common health problems across patient groups related to comfort, coping, fatigue, and decreased physical ability. Disease status, prostatic specific antigen, and a history of mental health problems were modest predictors of poor HRQL. 19% of patients with advanced prostate cancer were found to have a mental health disorder. The presence of anxiety and/or drepression was associated with significant declines in HRQL. Higher health care costs were observed in patients with mental health disorders and those receiving palliative care. Conclusions In applying a patient-focused approach, new opportunities for defining the APN role and improving care delivery in advanced prostate cancer were identified. The supportive care role of the APN involving early intervention and health promotion across the continuum of prostate cancer care was envisioned for key foci related to prostate cancer health, mental health, and functional capacity. Recommendations for developing the clinical and non-clinical aspects of the APN role in advanced prostate cancer are provided along with recommendations for future research.

abstract: Doctor of Philosophy (PhD)


title: The development of nurse decision making: A case study of a four year baccalaureate in nursing programme

contributor:
Boblin, Sheryl
Nursing

subject: Nursing Nursing

abstract: This project, which used a qualitative case-studying design, explored the development of decision making as nurses progressed through a baccalaureate education. More specifically, the study focussed on the types of decisions students made and the factors that influenced their decision making. Students from all four years, enrolled in problem based learning (PBL) and clinical courses were recruited for this study. In addition, Tutors from both the clinical and PBL courses were involved. In total, 76 students and Tutors participated. Data were collected through Key Informants (students, Tutors) and Key Documents (curricular material). Students in the PBL setting were asked to participate in either an individual semi-structured interview or in a focus group conducted by the principal investigator. For both settings, students were asked to complete reflective journals, which served as a stimulus for the interview. Tutors in the PBL setting were asked to participate in an individual and semi-structured interview or a focus group, while Tutors in the clinical setting were asked to articipate in an interview. Data were also collected from curricular materials provided by McMaster University, School of Nursing. Results of this study indicated that students engaged in decision making, and that they made five different types of decisions; assessment, communication, intervention, resource, and action. Results also showed that the types of decisions they made changed over the four years as did their approach to decision making. Students also described a shift in their focus over the four years and this was reflected in the types of decisions they made. Students described the influence of many internal and external factors and the collaborative nature of student decision making. One additional finding was the students' appraisal of the situation within which they made decisions. Students appraised the risk to them physically, scholastically, and professionally.

abstract: Doctor of Philosophy (PhD)


title: Participation Decisions by Labor Union Members: Theory of Planned Behavior and Personality

contributor:
Jain, Harish C.
Business Administration

subject: Business Business

abstract: The theory of planned behavior (TPB) was the theoretical framework applied to examine participation decisions by local labor union members. This study had several objectives: determine the dimensionality of union participation as a dependent variable; extend the TPB to include variables used in union participation research; test personality meaures; and test the predictive ability of the TPB over the theory of reasoned action (TRA). A factor analysis revealed that union participation in multidimensional, with three factors emerging. When personality and demographic variables were included, the amount of variance accounted for in union participation increased by 1 percent. A comparison of the TPB with the TRA also demonstrates support for the TPB. A relationship was found between perceived behavioral control (PBC) and gender, and for children under 12. The gender effect indicated that males have more PBC than do females, and when there are children under 12, there are issues with volitional control. No relationship was found to exist between PBC and race, or with disabilities. However, non-White members were found to have higher instrumental beliefs towards participation, as did persons with disabilities. A unique finding in this study was the relationship between subjective norms (SN) and participation, and between SN and intentions. A relationship was also found between beliefs and extraversion. These findings represent important policy consideration for unions. Unions need to be more creative in finding ways to make it easier for females and families to participate. Paid allowances may be necessary to cover expenses, holding meetings earlier in the evening to make it easier to attend, or locations that provide easy access. Leadership training may address some issues for members less extraverted. Unions musut also ensure that socialization of members, using retired union members or working with referent others is encourages, as it appears to be an important construct.

abstract: Doctor of Philosophy (PhD)


title: Structure and Function Studies of Hsp47: A Collagen-Specific Molecular Chaperone

contributor:
Ananthanarayanan, V.S.
Biochemistry

subject: Biochemistry Biochemistry

abstract: Heat shock protein 47 (Hsp47) is an ER resident protein and is considered to be a molecular chaperone specific for collagen. Although Hsp47 has been shown to be necessary for collagen biosynthesis, its exact roles(s) as a chaperone for collagen is/are unknown. Available evidence on type I collagen shows that Hsp47 binds to the nascent proα and proα2 chains and remains bound during triple-helix formation and subsequent export from the ER. Upon entering the cis-Golgi network, Hsp47 is thought to release procollagen and is subsequently returned to the ER. With a view to understanding the exact role of Hsp47 in collagen biosynhesis, we undertook biophysical and biochemical characterization of Hsp47. This involved purification of recombinant Hsp47 using the IMPACT™ T7 system. Purified Hsp47 existed as both a monomer and a trimer, and underwent pH-induced conformational changes that correlated to its collagen-binding activity. Hsp47 was shown to effectively inhibit type I collagen fibrillogenesis in vitro. This inhibition of fibre formation provided a novel assay for Hsp47 activity, as well as support for an in vivo role for Hsp47 in preventing collagen aggregation in the ER. Finally, in an attempt to map the binding site(s) on the collagen molecule, assays were designed to analyze the interaction of radio-labelled Hsp47 with CNBr fragments derived from type I and type II collagen. The results showed that Hsp47 preferentially binds to peptides from the N-terminal region of collagen in their triple-helical conformation

abstract: Doctor of Philosophy (PhD)


title: Direct Visual Servoing Using Network-Synchronized Cameras

contributor:
Capson, David
Electrical and Computer Engineering

abstract: A new strategy for direct visual servoing for robotic position control is described. The approach does not rely on any external position or velocity sensors but directly sets motor current using visual feedback alone. The method is novel in that it can be implemented without specialized version hardware and is capable of processing visual feedback at high frame rates suitable for stable closed-loop position control of practical mechanical systems. A single RS-170 camera has a maximum sampling rate of 60Hz that significantly limits visual servoing performance. This limitation is overcome with multiple RS-170 cameras synchronized over a network in round-robin fashion to capture video fields at different instants in time. "Vision nodes", consisting of a camera and a dedicated computer, continuously process video at field rates to determine robot position. The vision algorithm, which is based on principal component analysis, is demonstrated to be suitable for accurate real-time position determination. Furthermore, the Euclidean distance in eigensepace in the presence of random occlusions is shown to be statistically related to the position measurement error variance. This leads to a novel approach for dealing with occlusions by considering them as "noise", the variance of which can be estimated directly from the Euclidean distance in eigenspace. A Kalman filter is then introduced to provide sensor fusion of the feedback from each vision node by weighting the position estimates from each camera to provide an improved overall position estimate. The Kalman filter also models the vision transport delays to reduce their effects on the visual feedback. Simulation results illustrate improvement in dynamic performance as the number of cameras are increased. Further simulations predict robustness to simulated occlusions. An experiment was designed and performed to experimentally verify the strategy for direct visual servoing. A 1 DOF servo drive equipped qith a rotating link constituted a simple "planar robot" testbed for demonstrating the distributed visioni and control techniques. The testbed was built using "off the shelf components" consisting of a network of four RS-170 cameras and computers connected to a master servo computer over a 100Mbps Ethernet network. An effective visual sampling rate of 240Hz was achieved. Several techniques were developed to achieve deterministic communications over Ethernet. The limitations on the number of cameras was analyzed and it was found that the Ethernet network could theoretically support up to 826 cameras. The main limitation was found to be the processor time on the master servo computer. Experimental results are shown for the system performing direct visual servoing under various different conditions. A direct visual servo emplying four cameras exhibits a step risetime of 190ms which closely matches the performance using traditional encoder feedback. Additional experimental results demonstrate the servo-hold performance and step responses with and without occlusions. Both full occlusions in a subset of cameras and partial occlusions in all cameras were investigated. The experment results validate the simulation results and verify that the strategy is capable of stable direct visual servoing and is robust to occlusions. Additional experiments are included that demonstrate performance under varying illumination conditions and various tele-robotic extensions.

abstract: Doctor of Philosophy (PhD)


title: Multichannel Blind Estimation Techniques: Blind System Identification and Blind Source Separation

contributor:
Reilly, James P.
Electrical and Computer Engineering

abstract: The focus of this thesis is on blind identification techniques for multi-input, multi-output (MIMO) systems. In this respect we study three problems: 1. The joint diagonalization problem: Joint diagonalization is an efficient tool for blind identification techniques for MIMO systems. In this thesis we discuss new adaptive joint orthogonal diagonalization algorithms based on optimization methods over the stiefel manifold. 2. Blind identification of MIMO systems: We demonstrate that by using the second-oder statistics of the system outputs, by exploiting the non-stationary of sources, and some mild conditions on the sources and the system, the impulse response of the MIMO system can be identified up to an inherent scaling and permutation ambiguity. An efficient two-step frequency domain algorithm for identifying the MIMO system then has been proposed. Numerical simulations verify the theoretical results and the performance of the new algorithm. 3. Real room blind source separation problem: The final part of the thesis focuses on the practical problem of blind source separation of mixed audio signals in a real room. The new proposed algorithm exploits the non-stationarity of audio signals to separate them from their mixtures recorded in a reverberant environment. This method has successfully been applied to real data acquired during extensive recording experiments done in different office rooms on the McMaster campus.

abstract: Doctor of Philosophy (PhD)


title: Robust Position Measurement In Visual Eigenspace

abstract: A survey and analysis of visual measurement of camera and object position in visual sub-space (eigenspace) is provided leading to several improvements to existing methods, as well as new approaches. Specifically, novel techniques were developed to allow robust measurements in the presence of occlusions and other dynamic scene changes which is known to be a significant challenge in pose measurement methods for important applications such as visual servoing, autonomous robotics in manufacturing and tele-robotics including aerospace, medical operations and others. Local image information is shown to retain positional information in unoccluded regions that can then be used to determine position in the presence of significant dynamic occlusion. Local information is also shown to be more prone to ambiguity errors due to a lack of salient positional information. A subsectioning and recombination strategy is developed that features the advantages of local eigenspace independence for robustness to occlusion while maintaining the inherent resistance to ambiguity available from global eigenspace analysis. This is achieved by computing modified global projections, while excluding information from occluded sections. A new method for occlusion detection using an eigenspace reconstruction error measure is also developed and evaluated. A wide variety of experimental measurements are provided to demonstrate the performance of the new methods using an accurate XYZ platform and CCD cameras with metallic, machined parts. Experimental measurements are also performed to demonstrate improvements for eigenspace position accuracy through the use of multiple cameras. Several techniques are employed to combine and fuse multiple images from decoupled cameras whereby cameras are used for determining position in different directions to to improve accuracy. Subsequently, multiple cameras are applied to achieving three dimensional translational position measurements in visual subspace.

abstract: Doctor of Philosophy (PhD)


title: Studies on the Molecular Mechanisms of Hydrogen Peroxide-mediated Regulation of Cell Proliferation

contributor:
Singh, Gurmit
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract: Mammalian cells have the ability to endogenously generate and metabolize hydrogen peroxide (H₂O₂). This H₂O₂ can interact with protein and lipid components of intracellular signal transduction pathways to regulate cell behaviour. It has been demonstrated in our laboratory and by others that many types of cells, including transformed cells, require H₂O₂ for efficient growth in culture. Excess H₂O₂ has long been identified as a source of oxidative stress that can mediate cell growth arrest and death. However, the addition of the H₂O₂ scavenger catalase to culture media or the overexpression of intracellular catalase can block proliferation. This effect is reversed by inactivation of the enzyme or upon co-incubation of cells with H₂O₂ and H₂O₂-generating sources such as glucose oxidase. Thus, at non-toxic levels, H₂O₂ appears to act as a cellular growth factor. The purpose of this work is to help elucidate molecular mechanisms underlying this H₂O₂-regulated aspect of cell physiology. The effects of extracellular H₂O₂ level manipulation upon the activities of the HER-2/Neu receptor tyrosine kinase, mitogen-activated protein kinases (MAPKs), and stress-activated protein kinases (SAPKs) are discussed. The c-Jun-NH₂terminal kinase 1 (JNK1), a member of the SAPK family, is involved in several diverse aspects of cellular functioning including apoptosis and transformation. The JNK1 signal has also been implicated as a cell sensor of redox (reducing/oxidizing) stress. We have observed that the growth-inhibitory effect of both high level H₂O₂ treatment and H₂O₂-scavenging catalase treatment is accompanied by a transient increase in JNK1 activity. To determine the importance of this response in growth regulation, the JKN1 signal wa stably altered in SK-OV-3 human ovarian adenocarcinoma cells by the expression of ectopic JNK1 (HA-JNK1). Levels of HA-JNK1 protein expression correlated with increases in basal c-Jun phosphorylation in a dose-dependent manner. Transient expression of HA-JNK1 potentiated cell growth arrest by catalase activity, however with stable expression a degree of resistance to this response was observed. Resistance was accompanied by a lowered endogenous production of H₂O₂. Transient HA-JNK1 expression also reduced H₂O₂ generation, and this effect was reversed by the JNK inhibitor SP600125. These resultts indicate that the JNK1 stress response contributes to the inhibition of proliferation by catalase treatment, possibly via additional reductions in environmental H₂O₂ caused by a lowered endogenous production. Stable amplification of the JNK1 pathway leads to cellular adaptation to its signal, resulting in a diminished reliance upon basal H₂O₂ levels for efficient growth. These data contribute to the understanding of the mechanisms involved with the overexpression and/or hyperactivity of JNKs observed in certain cancers.

abstract: Doctor of Philosophy (PhD)


title: ULTRAFILTRATION AND DYSFUNCTION IN PERITONEAL DIALYSIS: THE ROLE OF INFLAMMATION, FIBROSIS, AND ANGIOGENESIS

contributor:
Gauldie, Jack
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract: Background: peritoneal dialysis (PD) is a valuable therapy for end-stage renal disease. Changes in the peritoneal transport properties, including increased solute transport and ultrafiltration (UF) dysfinction are main clinical limitations of PD. The capillary wall of peritoneal blood vessels plays a key role as a barrier to solute transport. Therefore, neovascularization of the peritoneal tissues is a main determinant in the functional changes in the peritoneal membrane. I hypothesize that ultrafiltration of dysfunction is caused by increased peritoneal vascularization with a concomitant increase in glucose transport from peritoneal cavity and rapid loss of the ultrafiltration gradient. Further, I hypothesize that this increased vascular surface area is induced by profibrotic and inflammatory cytokines such as transforming growth factor (TGF) β, interleukin (IL) 1β, and tumour necrosis factor (TNF) α through upregulation of angiogenic cytokines such as vascular endothelial growth factor (VEGF). Methods: I used adenovirus mediated gene transfer of cytokines such as TGFβ1, il-1β, and TNFα to the peritoneal of rats and studied the effects of histology, angiogenesis, gene regulation, solute transport, and UF. I also used an animal model of daily peritoneal exposure to dialysate solution. The angiogenic and fibrogenic response of the peritoneum to this model was detailed, along with the effect of overexpression of angiostatin and decorin by adenovirus mediated gene transfer Results: Adenovirus mediated gene transfer of TGFβ1 led to increased peritoneal fibrosis and angiogenesis which persisted to 28 days. These histologic changes were associated with increased solute transport of glucose and decreased UF. In vitro and in vivo, TGFβ1 appeared to up regulate expression of VEGF. Inflammatory cytokines such as TNFα and IL-1β both induced fibrosis, angiogenesis, and peritoneal membrane dysfunction. The kinetics of the response was quite different. TNFα induced a very transient response with a complete resolution of changes by 21 days after adenovirus infection. The response induced by IL-1β was more sustained. I hypothesize that the strong expression of tissue inhibitor of metalloproteinase after IL-1β treatment may explain the prolonged fibrogenic response after IL-1β. Daily exposure to dialysate also induced a strong fibrogenic and angiogenic response in the peritoneum. The anti-angiogenic agent angiostatin, when overexpressed using adenovirus mediated gene transfer, reduced the vascularization and improved the ultrafiltration dysfunction. Decorin, a proteoglycan that binds and inactivates TGFβ, reduced peritoneal fibrosis, but did not alter the angiogenic response, nor did it improve peritoneal membrane function. Discussion: These experiments have clarified the role of angiogenesis in UF dysfunction. The correlation between blood vessel density and ultrafiltration, along with the improvement in UF after treatment with angiostatin, is compelling evidence that vascularization of the peritoneal membrane causes UF dysfunction. There is a close associate between fibrosis and angiogenesis in the perotineum. Fibrosis appears to be necessary for a prolonged angiogenic response. Further work is required to identify the factors leading to the interaction between fibrosis and angiogenesis. The role of the interstitium and lymphatics in solute transport and UF dysfunction needs to be better defined. Finally, anti-angiogenic therapies need to be studied in these models of peritoneal membrane dysfunction and eventually applied to patients on PD to improve the quality and duration of this therapy.

abstract: Doctor of Philosophy (PhD)


title: The Targeting Mechanisms and Membrane Topology of Tail-Anchored Proteins

contributor:
Andrews, David W.
Biochemistry

subject: Biochemistry Biochemistry

abstract: Tail-anchored proteins are integral membrane proteins that are characterized by a transmembrane domain at the carboxyl-terminus of protein. The correct targeting and localization of tail-anchored proteins is essential for cell function and viability. In this thesis, the targeting mechanism and membrane topology of tail-anchored proteins were examined using a cell-free assay system. Initially, the targeting of tail-anchored proteins was thought to occur via spontaneous integration into the membrane bilayer. However evidence is presented in this thesis to suggest that more than one targeting mechanism exists. Unlike the spontaneous insertion of tail-anchored proteins such as cytochrome b5, one family of proteins (that includes proteins called Vamps) is shown to require both ATP and a membrane-bound receptor to mediate integration into the bilayer of the endoplasmic reticulum. The minimal region on Vamps that is necessary and sufficient to confer ATP-dependent and receptor mediated targeting was identified. Within this region are four lysine residues spaced along an amphiphatic helix that was found to be necessary for binding of Vamps to endoplasmic reticulum. While spontaneous insertion is sufficient to account for membrane integration for cyctochrome b5 and Bcl-2 data was obtained suggesting that specific localization is achieved by regulating targeting. The membrane topology of one of this class of tail-anchored protein wa examined using chemical modifying techniques. The membrane topology of Bcl-2 is shown to be dynamic, as it changes in cells treated with chemotherapy drugs. This represents the first evidence of a tail-anchored protein that changes membrane topology in response to a cellular signal

abstract: Doctor of Philosophy (PhD)


title: Crystal structure and hydroxyapatite binding of osteocalcin from porcine

contributor:
C., Daniel S.
Biochemistry

subject: Biochemistry Biochemistry

abstract: Osteocalcin is a bone specific protein produced by osteoblast. The strong association of osteocalcin with bone rendered it a principal biological market for bone metabolism and the most characterized among non-collagenous bone matrix proteins. To gain insight into the function of osteocalcin, the crystal structure of osteocalcin has been determined to 2.0 Å resolution. Contrary to a previous hypothesis that osteocalcin is largely disordered; the crystal structure of osteocalcin is tightly folded. One surface of the structure is relative flat and consists of only negatively charged residues. The arrangements of carboxyl groups on the ϒ-carboxylated glumatic acid residues closely mimic the arrangement of phosphate groups in hydroxyapatite, and they chelate five calcium atoms in the dimer interface with near perfect coordination geometry. When docked to the surface of hydroxyapatite, this surface complimented near perfectly the prism face of hydroxyapatite. The excellent complimentary clearly indicates that osteocalcin can bind to hydroxyapatite with high specificity, it seems reasonable that the presence of bound protein will inhibit further crystal growth on this surface.

abstract: Doctor of Philosophy (PhD)


title: INVESTIGATION OF THE INFLUENCE OF CADMIUM PROCESSING ON Zn₁₋ᵪGa₂O₄₋ᵪ Mn THIN FILMS FOR PHOTOLUMINESCENT AND THIN FILM ELECTROLUMINESCENT APPLICATIONS

contributor:
Kitai, A.H.
Engineering Physics

subject:
Engineering Physics
Engineering Physics

abstract: Cadmium processing of ZnGa₂O₄films provides a new fabrication route for phosphor powders and thin films. It relies on the enhanced diffusion due to the large vacancy concentration left by the sublimation of cadmium. Photoluminescent powders can be made with a single high temperature firing. Thin film devices can be processed at a significantly lower temperature, expanding the range of available substrates. Powders and thin films of ZnGa₂O₄: Mn were fabricated using starting materials in which between 0% and 50% of the ZnO was substituted by CdO. It was found that the emission spectra of the various compositions was unaffected by the change in composition, peaking at 504 nm, with the colour coordinates x=0.08 and y=0.69. The invariance of the emission spectrum is due to the spinel crystal structure exhibited by the compound. However, the maximum PL brightness was obtained from powders in which 10% of the ZnO had been substituted by CdO in the starting materials. The improved brightness is the result of better manganese incorporation which resulted from CdO sublimation during processing. This left a large vacancy concentration which enhanced the diffusion, and hence the manganese incorporation. In the case of thin films sputtered from cadmium processed targets, the composition of the films as deposited closely mirrored that of the target starting materials. The as deposited films were not luminescent and had to be annealed in vacuum in order to activate the manganese. EDX of these films showed that all of the cadmium had sublimed during the anneal. Very long anneal times also resulted in the loss of zinc. The decomposition products were amorphous or nanocrystalline. These films had an identical PL emission to the powders. The loss of cadmium correlated with the onset of bright 254 nm photoluminescence in the films, indicating that cadmium loss aided in the activation of the manganese. This was the result of the enhanced diffusion due to the large vacancy concentration left by the sublimed material, which aided the incorporation and activation of the manganese. The cadmium in the sputtering targets also impacted the crystal structure of the films. Films from cadmium free targets exhibited a strong (111) x-ray diffraction peak, while those from cadmium processed targets more closely resembled the powder structure. The optimum thin film electroluminescent performance was obtained for films sputtered from targets processed with between 5% and 15% cadmium substituted for zinc. This was the result of improved diffusion during the anneals, due to the sublimation of cadmium oxide and the resulting large vacancy concentration. The best performance was obtained for films annealed at between 875∘C and 900∘C for 6-12 hours. These films exhibited both the maximum luminance (55 cd/m² at 60Hz) and the lowest transferred charge (~20 μC/cm²). This combined for a peak efficiency of 0.5 Im/W at 60 Hz). Beyong 12 hours at 900∘C or temperatures higher than this, EL performance degraded due to the decomposition of thin film. It was concluded that the luminescent performance of this material is strongly influenced by the loss of cadmium during processing. The enhanced diffusion afforded by the cadmium sublimation results in improved EL performance at annealing temperature lower than that of pure zing gallate.

abstract: Doctor of Philosophy (PhD)


title: CHARACTERIZATION OF AAC(6')-APH(2"), A BIFUNCTIONAL AMINOGLYCOSIDE MODIFYING ENZYME

contributor:
Wright,  Gerard D.
Biochemistry

subject: Biochemistry Biochemistry

abstract: AAC(6')-APH(2") is a bifunctional enzyme which catalyzes the inactivation of aminoglycoside antibiotics by ATP-dependant O-phosphorylation and acetyl coenzyme A-dependant N- and O-acetylation. it is the most prominent aminoglycoside-modifying enzyme found in gentamicin-resistant clinical isolates of Enterococci and Staphylococci. Although capable of inactivating all 2-deoxystreptamine aminoglycosides, gentamicin is the most clinically important substrate commonly administered in combination therapies to treat nosocomial Enterococcal infections. Gentamicin-resistant clinical isolates carrying aac(6')-aph(2") are characterized by high level resistance to gentamicins and other aminoglycosides. In an attempt to obtain a more thorough understanding of it's functionalities and develop strategies to inhibit its' function in vivo, studies were initiated to characterize the substrate specificities, the regiospecificities of inactivation, and the potential for generation of lead compounds with inhibitory action towards AAC(6')-APH(2"). The studies reported herein, identify: i) two novel activities exhibited by AAC(6')-APH(2") (a Serine protein kinase activity exhibited by the phosphoransferase APH(2")-Ia and an O-acetyltransfer activity exhibited by the acetyltransferase AAC(6')-Ie, ii) the substrate structural requirements for enzyme/substrate interactions, iii) an unanticipated regiospecificity of inactivation of the 4, 5-disubstituted aminoglycosides and iv) inhibition of the APH(2")-Ia by isoquinolinesulfonamide protein kinase inhibitors.

abstract: Doctor of Philosophy (PhD)


title: Evil in Modern Theatre: Eschatology, Expediency, and the Tragic Vision

contributor:
Planinc, Zdravko
Religious Studies

subject: Religion Religion

abstract: This thesis contributes to scholarship on the subject of evil, as well as to scholarship concerning the ethical and political significance of theatre. It is guided by two central questions: the question of how the modern experience of evil has been represented by important works of dramatic literature, and the question of how the experience of evil in general is central to the nature of theatre itself. I discuss the phenomenon of "modern evil" by examining the significant examples of Renaissance and twentieth century drama. Insufficient scholarly attention has been paid to the fact that theatre was a vibrant aesthetic during the early modern and late modern periods, reflecting both thte impulses that initiated the modern project and the sufferings that led to its revaluation. Through plays by Niccolo Machiavelli, William Shakespeare, Albert Camus, and Samuel Beckett, I examine the ethics of both Machiavellian expediency and eschatological utopianism. I argue that these two dominant orientations have given modern evil its distinctive character, and contributed to the unprecedented violence and suffering of the twentieth century. In association with this discussion, I consider how the most significant periods of dramatic art have occurred during moments of crisis, violence, and transition. It was during such historical spocs - when the reality of evil was extremely acute - that threatre arose as a dominan aesthetic. Though theatre has often been symptomatic of the excesses explored in this study, I argue that the very nature of theatre - as a medium of evil. The tragic vision is a distinct alternative to the expedient and eschatological impulses that have dominated Western society for the past two millennia and that have eclipsed our ancient Greek theatrical heritage.

abstract: Doctor of Philosophy (PhD)


title: NEURO MAGNETIC STIMULATION: ENGINEERING ASPECTS

contributor:
Bruin, H. de
Electrical and Computer Engineering

abstract:
Magnetic nerve stimulation has proven to be an effective, non-invasive technique to excite peripheral and central nervous systems. In this technique, the excitement of the neural tissue depends on exposure to a transient magnetic field generated by passing a high pulse of current through a coil. By positioning the coil in a specific orientation over the targete tissue, the transient magnetic field will induce an electric field in the conductive milieu of the body. If this field reaches a certain threshold within a specific time period, neural depolarization is then evident.

Recently, transcranial magnetic stimulation showed promise as a novel treatment for mood disorder and other psychiatric illnesses. Considering that these sicknesses are currently one of the larges causes of disability (with a cost sometimes exceeding that of diabetes, heart disease, and hypertension) it is evident that pursuing this therapeutic approach is beneficial. However, as magnetic stimulation is relatively new, many limitations and obstacle are to be addressed before this innovative technology is approved for clinical applications.

The main limitations in applying magnetic nerve stimulation are poor field focality and inadequate strength in deep tissues (targeted area). This, the excitation of these regions requires very high coil currents to achieve a strong field that is capable of penetrating deep tissues. However, these fields might activate adjacent tissues as well as the targeted area. Further, the high currents will result in coil heating, especially for a high rate of repetition.

Another limitation, especially in transcranial stimulation, is the lack of knowledge of precisely which area of neural tissue is being affected since no immediate behavioral effects of current reversal in the coils and the virtual cathode of the coil suggests conflicting results.

The primary objective of this thesis is the development and testing of new coil designs that can focus the magnetic field more effectively. Two such coils have been built. The first coil has an air core, while the other has a magnetic core. The magnetic fields of these coils, applied to the human upper limb, have been determined theoretically, and the results compared to the field generated by the most generated by the most common commercial coil, the Figure-8 coil. To design these coils and to test them experimentally, a current pulse generator has been designed and built. Further, a novel meaurement system using surface mount inductances and a computer based data acquisition system has been designed and built. The experimental results confirm the theoretical findings, that the air core coil is slightly better than the Figure-8, as far as field strength and focality are concerned. In addition, the experimental results, prove that the coil with the ferromagnetic core, is superior.

The second objective is to investigate the effect of stimulus waveforms theoretically, experimentally, and through in vivo study. The goals of the study are to establish a quantitative relationship among various waveforms and to investigate the effect of these waveforms in determining the site of stimulation. Accordingly, a multi subject trail was conducted: a Figure-8 coil was applied to the median nerve of ten subjects at the upper limb. The motor responses of the thenar muscle were then recorded. The study results show that the biphasic stimulating pulse is more effective than the monophasic pulse, as has been concluded by other researchers.

However, the effective stimulating point, or virtual cathode of the coil, was found to be not simply 3 to 4 cm from the coil center as had been reported. In fact, the study shows that the site of the virtual cathode is affected by the current amplitude and the degree of inhomogeneity of the tissues surrounding the nerve. Furthermore, reversing the coil current direction results in a different level of stimulation but does not affect the virtual cathode position.

In summary, the research presented in this thesis covers theoretical concepts, experimental aspects, and human studies related to neuro magnetic stimulation. The results of the experiment and the study are consistent with the theoretical analysis. The proposed coil design is novel and offers promise for a better coil system for magnetic nerve stimulation

abstract: Doctor of Philosophy (PhD)