title: Experimental Manipulation Which Results in the Phenotypic Expression of the Dystrophic Process: Cross-reinnervation of a Slow Tonic Muscle by the Nerve of a Fast Twitch Muscle in Chickens With Hereditary Muscular Dystrophy

contributor:
Cosmos, Ethel
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
In chickens afflicted with hereditary muscular dystrophy, the two major types of muscle present respond dissimilarly to the disease process: fast twitch glycolytic muscles possess and express the dystrophic gene overtly during ex ovo development while the genotypically dystrophic slow tonic muscles fail to express dystrophic phenotypes. Therefore, in chickens, muscular dystrophy is muscle fibre type specific.

The primary goal of this thesis was to experimentally alter the genetically dystrophic slow tonic musle in an attempt to induce this muscle to express dystrophic phenotypes. Since motor nerves influence the phenotypes of skeletal muscles, it was decided to replace the motor innervation of a slow tonic muscle with that of a fast twitch muscle within a-dystrophic chicken. The surgical cross-reinnervation between the ALD muscle and the 'fast' nerve was performed at hatching by transposing the right ALD muscle to the left side of the back in order to prevent selective self-reinnervation by the severed ALD nerve. The experimental muscles were examined at various time intervals from 2 to 104 weeks postoperatively and compared to age-matched ALD muscles in genetically normal chickens. In addition, denervation of ALD muscles, with and without transposition served as control experiments.

Selected histochemical and structural properties of unoperated ALD and fast twitch posterior latissimus dorsi (PLD) muscles of normal and dystrophic chickens were compared between 2 and 32 weeks ex ovo to provide criteria for the analysis of muscles cross-reinnervated by 'fast' nerves and to determine which of these parameters were altered as a result of the dystrophic process. Normal and dystrophic ALD muscles exhibited similar phenotypes: acid and alkaline stable myosin ATPase activity, 'en grappe' endplates, weak glycolytic and strong oxidative capacities, and peripheral location of nuclei. Furthermore, the growth rate, size, and shape of fibres in the normal and dystrophic ALD muscles were similar. In contrast, the myosin ATPase and innervation patterns of normal and dystrophic PLD muscles differed from those of ALD muscles: PLD fibres of either genotype exhibited alkaline stable, acid labile myosin ATPase activity and focal 'en plaque' innervation. Normal and dystrophic PLD muscles also exhibited different phenotypes: dystrophic muscles had a lower muscle weight, abnormal size, shape, and growth rate of fibres, increased number of scattered nuclei, add abnormal glycolytic and oxidative capacities.

The results presented from this work indicate that the genetically dystrophic ALD muscles respond differently to cross-reinnervation than do normal ALD muscles. The cross-reinnervated muscles in normal birds demonstrated all of the characteristics of an unoperated ALD muscle with the exception of the presence of isolated groups of fibres exhibiting a fast twitch type of myosin ATPase response. This result suggests that the principle response of normal ALD muscles to a foreign 'fast" nerve is one of resistance to alteration. In contrast, data from the experimental ALD muscles of dystrophic genotype support the conclusion that these muscles are dramatically remodelled after cross-reinnervation. An augmented regenerative response within the dystrophic muscles resulted in hyperplasia which, in turn, led to a complete restructuring of these muscles. Therefore, the present cross-reinnervation experiments demonstrate, for the first time, that a phenotypically normal muscle of dystrophic genotype can be induced to express a dystrophic characteristic: an augmented regenerative response after an experimentally-induced injury. It is important to note that the initial induction of this dystrophic phenotype was demonstrated in the absence of the foreign 'fast' nerve and seemed to be due to the response of this muscle to the severe injury imposed upon the muscle during the inital operation.

abstract: Doctor of Philosophy (PhD)


title: Design, Fabrication and Characterization of n-Channel InGaAsP-InP Based Inversion Channel Technology Devices (ICT) for Optoelectronic Integrated Circuits (OEIC): Double Heterojunction Optoelectronic Switches (DOES), Heterojunction Field-Effect Transistors (HFET), Bipolar Inversion Channel Field-Effect Transistors (BICFET) and Bipolar Inversion Channel Phototransistors (BICPT).

contributor:
Simmons, J.G.
Thompson, D.A.
Engineering Physics

subject:
Engineering Physics
Engineering Physics

abstract: This thesis demonstrates inversion channel technology (ICT) as a viable technique for realizing InGaAsP-InP based monolithic optoelectronic integrated circuits (OEIC). Inversion channel technology utilizes a common substrate and a common fabrication sequence to monolithically integrate electrical, optical and optoelectronic devices, therefore, requiring compatibility in both the device structure and fabrication sequence. This technology is demonstrated by designing, fabricating and characterizing four types of ICT devices, the DOES, HFET, BICFET and BICPT, on a common structure with a common fabrication sequence. These devices were selected because they are complementary in function and provide the circuit designer all the basic elements for building monolithic OIECs: optical emitter, optoelectronic switches, bipolar and unipolar transistors, and photodetectors. Device models for InGaAsP-InP based DOES, HFET, BICFET and BICPT are developed and used to design the four device structures used in this work. These models identify the effect of device structure on the performance of the devices. The device models are also used to predict the input, output and transfer characteristics of each type of device. This provides an understanding of device physics and operation, and a basis for comparison with experimental results. A common fabrication sequence and fabrication recipes for self-aligned n-channel InGaAsP-InP based DOES, HFET, BICFET and BICPT is designed, developed and demonstrated. This includes the photomask set for self-aligned ICT devices, SiO₂ masking for self-aligned contact formation, SiO₂ sidewall passivation of mesas for ion-implantation, high accuracy RIE etching with a an in-situ QMS, implant activation for n- and p-implants in InGaAsP-InP, and metallization over tall vertical mesa structures. The operation of the DOES, HFET, BICFET and BICPT is demonstrated experimentally. Complete sets of electrical, optical and optoelectronic measurements of the input, output and transfer characteristics of each type of device is performed. These characteristics are compared with the theoretical predictions made by the models to validate the operation of each type of device. This work demonstrates ICT as a technology for realizing OEICs in the InGaAsP-InP material system, and presents the technology required to design, fabricate and characterize these integrated devices.

abstract: Doctor of Philosophy (PhD)


title: A Geochemical and Isotopic Study of Plutonic and High Grade Metamorphic Rocks from the Chandos Township Area, Grenville Province

contributor:
McNutt, Robert H.
Shaw, Denie M.
Sociology

subject: Sociology Sociology

abstract:
The geological history of the Chandos township region in the Grenville Province of Ontario and the behaviour of the Rb-Sr system in response to an amphibolite grade regional metamorphism have been investigated by comparing Rb-Sr whole rock and U-Pb zircon and sphene ages determined, in most cases, from the same sampling site. A variety of sampling techniques have been employed in order to evaluate the geological significance of Rb-Sr whole rock ages in complex, high grade terrains.

In the case of the layered sodic Apsley gneiss, samples collected from widely spaced sampling sites result in a more precise but anomalously old (1402 Ma) and geologically meaningless age; a consequence of combining genetically unrelated samples. Although Rb-Sr w~ole rock ages determined using samples collected from homogeneous portions of individual sampling sites are in better agreement with the inferred age of the Grenville Supergroup (ca. 1250 Ma), the best estimate for the age of the sodic Apsley gneiss is 1333±24 Ma, obtained by combining all the samples that have an igneous origin. A minimum estimate for the deposition and extrusion of these supracrustal rocks is the precise U-Pb zircon age of 1254 +11/-4 Ma (the Rb-Sr whole rock age for this site is 1244±32 Ma) obtained for the Tallan Lake sill.

Precise U-Pb zircon ages for two other intrusive bodies in the study area, the Methuen quartz mozonite and Loon Lake monzonite, indicate igneous activity at 1242 +22/-6 and 1090 +7/-4 Ma, respectively. Most of the granitoid rocks in the Central Metasedimentary Belt have low initial strontium ratios (0.703 to 0.704) and anomalously high oxygen isotopic compositions (> 8%) indicating that these units were derived from a source with a low average Rb/Sr and/or a source with a relatively short crustal residence history, and subsequently interacted with high-¹⁰O rocks (eg. marble) at depth, but did not interact with "old", high Rb/Sr crustal material).

The timing of amphibolite grade metamorphism is unclear, however, a minimum estimate is provided by the 1090 Ma U-Pb zircon age obtained for the post-tectonic Loon Lake monzonite. At present, there is no reliable maximum estimate but the 1150 Ma Rb-Sr study determined using thin slabs from the sodic Apsley gneiss is interpreted to be close to the time of metamorphism. If the occurrence of 1085 Ma U-Pb sphene ages in this region reflects new sphene growth or resetting during metamorphism then these ages, combined with the lack of evidence for new zircon growth, indicate that the region cooled slowly from approximately 600 to 650°C (ie. the blocking temperature for zircon) at 1150 Ma to approximately 500°C (ie. the blocking temperature for sphene) at 1085 Ma.

The final geological activity in this region was late-stage faulting, injection of pegmatite and associated hydrothermal activity. The effects of this event are recorded in the Rb-Sr whole rock system of the SiIent Lake gneiss, the potassic Apsley gneiss and fracture-bearing samples of the Tallan Lake granodiorite. The best estimate for the timing of this activity is the Rb-Sr whole rock age of 1023±17 Ma determined using fracture-bearing samples from the Tallan Lake granodiorite.

The different sampling techniques employed in this study indicate that the scale of Rb and/or Sr migration in the sodic Apsley gneiss, during metamorphism, must be less than one meter (the minimum distance between samples collected from one sampling site) and greater than 1 centimeter (the average width of the slabs). A more profound effect on the mobility of these elements was found in samples that have been affected by the late-stage hydrothermal activity. In certain rock units of the Rb-Sr system has responded to at least two distinct events, a regional amphibolite grade metamorphism at about 1150 Ma and hydrothermal activity at about 1025 Ma; so some caution should be execized in interpreting the geological significance of Rb-Sr whole rocks ages determined in this region.

abstract: Doctor of Philosophy (PhD)


title: Personality, Cognitive Ability and Behaviour: The Antecedents of Effective Autonomous Work Teams

contributor:
Hackett, Rick
Business Administration

subject: Business Administration, Management, and Operations

abstract: The aims of this study are three fold: (1) to identify the trait profiles (combination of personality attributes and cognitive ability) of effective team members, (2) to identify those behaviours linking personality attributes to effective team performance and (3) to identify those behaviours linking cognitive ability to effective team performance. The primary contribution of this study is in meeting the last two objectives. Ultimately, the objective was to relate team members' personality and cognitive ability to the team's performance by better understanding the intervening (in)effective behaviours. Subjects were 480 second year undergraduate business students in 94 teams of 5 to 6 members. Teams can be examined at two levels -- at the level of the individual team member and at the level of the team (by combining individual team member attribute information and relating it to team performance). At the level of the individual team member, three of the Big Five personality traits -- extroversion, conscientiousness and cognitive ability -- predict the effectiveness of team members. However, team members who are very high in extroversion tend to be unfocused and this is detrimental to their performance. At the team level of analysis, the greater the proportion of team members high in cognitive ability, conscientiousness, extroversion and openness to experience the better a team performs. Using findings from the two levels, it is suggested that human resource practitioners select team members who are in the top one-third of the population in openness to experience and conscientiousness. They should select extroverts with percentile ranking between 66% and 93%. Lastly, they should seek people high in cognitive ability. Team members engage in specific (in)effective behaviours. These behaviours were grouped and a typology emerged that was confirmed through Confirmatory Factor Analysis and builds on previous typologies. The identification of these behaviours is essential to training people to become more effective team contributors. Generally, neurotic team members are unfocused, ineffective in conflict situations and provide the team with little input. Extroverts are active members but tend to be unfocused. Members open to experience generate ideas, encourage others to express ideas and synthesize and summarize team ideas. Agreeable team members communicate effectively, avert conflict and ensure everyone participates. Conscientious team members focus on task-related behaviours -- set goals, get everyone working towards the goals and monitor progress. Team members high in cognitive ability not only take on task-related behaviour but are also socially adept.

abstract: Doctor of Philosophy (PhD)


title: Kant's Defence of Freedom: An Analysis of the Third Antinomy

contributor:
Ajzenstat, S.
Philosophy

subject: Philosophy Philosophy

abstract:
It can be argued that the most fundamental problem for Kant in the third "Antinomy" is that of personal identity. It is argued that an analysis of the third "Antinomy" leads to the problem of personal identity, because the solution to that problem provides the necessary grounds for justifying that the human will is free. In the last analysis, and in spite of the lack of Kant's explicit acknowledgment of the problem, the ultimate grounds for freedom can be none other than a knowledge of what it means to be a person.

This thesis does not pretend to solve the issue of personal identity. It simply attempts to connect the problem of freedom to that of personal identity within the confines of Kant's system. In so doing, it also raises the problem of having to step beyond the bounds of the criteria for knowledge in Kant. Hence, a new antinomy may have arise.

abstract: Master of Arts (MA)


title: The Use of Deep-Sea Corals as Paleoceanographic Monitors

contributor:
Schwarcz, Henry P.
Geology

subject: Geology Geology

abstract: The study of past ocean processes is essential to the understanding of current oceanography and climate systems, and to the prediction of future global change. The study of paleoceanography requires proxies: to date many studies have used foraminifera and reef corals. Each of these tools, however, has its limitations. The time resolution of paleoceanographic reconstruction using forams can be very poor, while reef corals can only give information about shallow, tropical processes. Azooxanthellate corals, in contrast, are suitable for highly precise and accurate radiogenic dating and are found everywhere in the world oceans, at all depths. The few attempts to use this taxon for paleoceanographic work have been, for the most part, unsuccessful. This is because the techniques for decoding the environmental information stored within azooxanthellate skeleton had not yet been developed. This thesis represents the first attempt to extract paleoceanographic information from 'deep-sea' corals and is presented in five sections, each a published for publishable manuscript. Part 1 describes an investigation of corals from Orphan Knoll (Desmophyllum cristagalli from 1600 m depth), in the northwest Atlantic. They were dated by the ²³⁰Th/²³⁴U method using thermal ionization mass spectrometry (TIMS) and found to have grown around the time of the Younger Dryas cooling event (13,000 to 11,700 calendar years BP). The origin of this cooling recently been attributed to a reduction or cessation of deep-water producution in the North Atlantic and a concurrent lessening of the heat flux from low latitudes. The δ¹⁸O in the coral skeletons shift markedly, coincident with the initiation of the Younger Dryas, suggesting that profound changes in intermediate water circulation may have occurred. Part 2 describes a study of skeletogenesis in deep-sea corals in order to develop a suitable isotopic sampling scheme for 'time-series' analyses. Numerous scanning electron micrographs of D. cristagalli have shown that this organism has skeletal banding analogous to that in reef corals. A long term record will be difficult to collect from D. cristagalli since lamellae are less than 10 μm thick, band position is unpredictable and degree of band dissolution is difficult to assess. Part 3 attempted to ascertain if portions of the coral skeletons displayed minimal isotopic disequilibria. A specimen of D.cristagalli was intensively sampled on all interior and exterior coeval surfaaces. Even though the coral grew at an almost-constant temperature, δ¹⁸O varied by almost 3% and was up to 3.25% depleted with respect to aragonite-seawater oxygen isotope equilibrium. Portions of the skeleton approached equilibrium, the location of those areas were unpredictable and were not associated with any readily-identifiable characteristics. Part 4 describes the study of thirty-five azooxanthellate corals belonging to 18 species, collected at sites ranging from the Norwegian Sea to the Antarctic and of depths ranging from 10 to 5220m. All specimens showed distinct, well-defined linear correlations between carbonate oxygen and carbon isotopic composition, with slopes ranging from 0.23 to 0.67 (mean 0.45 ± 0.9) and linear correlation r² values which averaged 0.89. These pronounced isotopic disequilibria are what have rendered azooxanthellate corals unsuitable for use in paleothermometry to date. Despite the disequilibria, a reliable method for obtaining paleotemperature data was obtained. It was found that, if a δ¹³O vs δ¹³C regression line from an individual coral could be generated, the δ¹⁸Oarag value corresponding to δ¹³Carag = δ¹³Cwater and corrected for δ¹⁸Owater was a linear function of temperature: δ⁸ O= -0.25 T(℃) + 4.97. Part 5 describes a study of trace-element and stable-isotope analyses which was performed on two sets of azooxanthellate corals from the North Atlantic: one set from Orphan Knoll and the other from the Mid-Atlantic-Ridge. The Mid-Atlantic-Ridge corals had episodic pulses of Fe, Mn, Cu, Ni and Zn contained within their skeletons. We believe these metals originated in a hydrothermal discharge zone associated with the Mid-Atlantic spreading centre. With sufficient specimens of known ages, it may be possible to reconstruct the history of a particular segment of a spreading centre.

abstract: Doctor of Philosophy (PhD)


title: Advances in Optimization of Circuits and Systems Using Recent Minimax and ℓ₁ Algorithms

contributor:
Bandler, John W.
Electrical Engineering

subject:
Electrical and Electronics
Electrical and Electronics

abstract:
This thesis concerns itself with computer-aided techniques for design centering, tolerancing and tuning, fault location and model parameter identification from measurements.

Since many of the engineering system problems discussed in this thesis are formulated as optimization problems we examine algorithms and techniques for nonlinear optimization. Our attention is focused on minimax and ℓ₁ algorithms since many formulations of engineering system problems exploit the characteristic features of these two norms.

A novel approach for worst-case network design is proposed and an algorithm for the fixed tolerance problem embodying worst-case search and selection of sample points is presented.

The features of the ℓ₁ norm in the tuning problem are discussed in detail and explained using necessary conditions for optimality of the nonlinear ℓ₁ problems with nonlinear constraints. Regular and singular ℓ₁ problems are defined and a criterion for determining a singularity present in the ℓ₁ problem is formulated.

New formulations using the ℓ₁ norm are given for fault isolation and model parameter identification in analog circuits.

Practical engineering problems have been solved illustrating the wide applicability of the concepts used and the robustness of the algorithms employed.

A new algorithm for minimizing the cardinality of a set subject to nonlinear, nondifferentiable constraints is presented and illustrated by solving the best mechanical alignment problem. The load shedding and generation rescheduling problem in power systems is formulated using the ℓ₁ norm. The formulation is tested on 6-bus and 26-bus power systems. A general microwave multiplexer design procedure exploiting exact network sensitivities is introduced and illustrated by designing 5-channel, 11 GHz and 12-channel, 12 GHz multiplexers.

abstract: Doctor of Philosophy (PhD)


title: Genetic Analysis of Complex Neurodevelopmental Disorders: A Model for the genetic etiology of autism and the related pervasive develomental disorders and Mapping of a gene responsible for X-linked mental retardation

contributor:
White, Bradley N.
Biology

subject: Biology Biology

abstract: The genetic factors underlying many of the major neuropsychiatric disorders have so far escaped elucidation, due to their complex segregation patterns and confounding influences such as heterogeneity and non-genetic influences. Approaches which are specifically suited to these types of problems have been developed, and are currently being applied to the genetic analysis of complex disorders. Two examples of such approaches are described here: the identification of genes involved in the etiology of autism and the pervasive developmental disorders (autism/PDD) using affected sib pair and allelic association methods, and the linkage analysis of X-linked mental retardation in an extended pedigree. The excess of males in the autistic/PDD population suggests the involvement of a locus on the X chromosome in the etiology of this group of disorders. In thirty-two pairs of affected brothers (male multiplex sibships), no evidence of increased sharing of maternal alleles was found at any of 16 highly polymorphic loci distributed along the X chromosome. However, at loci in the monoamine oxidase A gene in Xp11.23-11.4, the mothers of these affected sib pairs showed decreased heterozygosity. A haplotype consisting of the B2 and 122 bp alleles at two polymorphisms in the gene was found to be significantly more frequent in mothers of male multiplex sibships than in controls (x²=16.22, 14 df, p<0.05). As the affected siblings were not concordant for this haplotype more often than expected by chance, these data suggest that maternal genotype plays a role in the etiology of autism/PDD, i.e. that altered maternal MAOA activity results in the exposure of the fetus to abnormal monoamine neurotransmitter levels at a critical point in development, leading to autism/PDD. In the same set of male multiplex sibships, evidence was found for increased concordance near the serotonin transporter in 17q11.2-q21 (x²=7.11,1 df, p<0.01) and the dopamine transporter in 5p13.3 (x²=5.24, 1 df, p<0.025). Concordance was significantly increased for maternal, but not paternal, alleles at these loci. No significant increase in concordance was found for a locus linked to the norepinephrine transporter gene in 16q12.2. These findings suggest roles for the serotonin and dopamine transporters in the etiology of autism/PDD in these families. On the basis of these results in male multiplex families and other evidence from the literature, a model for the etiology of autism/PDD is proposed, in which the disorder arises from exposure of the fetus at a critical stage of development to abnormal monoamine neurotransmitter levels from maternal serum, due to a combination of maternal and fetal genotypes,and influenced by environmental factors. This model explains most of the unusual genetic features of autism/PDD. Two-point linkage analysis was used to map the locus responsible for X-linked mental retardation with macrocephaly and seizures (MRX38) in a single family with five affected males, to Xp21.1-p22.13, with a peak lod score 2.71 with no recombination. The region of localization is bounded by recombination events with DXS1226 distally and DXS1238 proximally, defining a genetic interval of approximately 14cM. The MRX38 locus maps to a region overlapping several other MRX localizations, but appears to represent a novel X-linked mental retardation entity.

abstract: Doctor of Philosophy (PhD)


title: An Integrated High Speed Flywheel Energy Storage System for Peak Power Transfer in Electrical Vehicles

contributor:
Szabados, B.
Electrical and Computer Engineering

subject:
Electrical and Computer Engineering
Electrical and Computer Engineering

abstract: An investigation is conducted into the practical electric vehicle implementation of a high speed flywheel energy storage system that can supply and accept peak acceleration and braking power. Electric vehicle battery life cycle can be extended considerably by supplying peak energy requirements from a secondary source. Simulations are performed to determine the peak power and energy requirements over the SAE recommended electric vehicle test procedure. A scaled prototype secondary energy storage unit is built using flywheel energy storage. Tests are conducted to determine the energy transfer capabilities of a flywheel couples high speed permanent magnet synchronous machine through the proposed system's energy storage tank. Results are presented that indicate the necessity of the energy storage tank. A system evaluation is also included which indicates its near-term practically when compared to conventional regenerative control applications. Construction techniques are discussed for the development of high speed drive circuits used in electrically noisy environments. Shielding and electromagnetic interference reduction methods are proposed for application to an actual high efficiency sinusoidal phase current, microprocessor interfaced, vector controlled, high speed permanent magnet synchronous machine drive. A discussion on the theory and construction of such a drive is provided to demonstrate the implementation of a laboratory prototype high speed flywheel energy storage system. An experimental investigation is conducted using the developed high speed drive to determine permanent magnet synchronous machine parameter behaviour in the high speed flux weakening operating range. Special computer assisted measuring techniques are used to determine the realtime operating characteristics for two commercially available machines. The repeatable experimental results show a significant variation in the machine parameters as a function of the speed and torque angle. Implications of the newly identified dynamic parameters are discussed regarding their application to, and effect on, high performance permanent magnet synchronous machine torque control.

abstract: Doctor of Philosophy (PhD)


title: Silanes and Allylsilanes as Possible Precursors for Transition Metal-Stabilized Silylium Ions

contributor:
McGlinchey, M.J.
Brook, Michael A.
Chemistry

subject: Chemistry Chemistry

abstract: Extended Huckel molecular orbital calculations on silicon cations [HC≅C-SI(CH₃)₂Co₂(CO)₆]⁺ reveal that the favored geometry for this silylium ion requires the SiH₂ group to lean towards a Co(CO)₃ vertex. This parallels the known behavior of carbocations with metal cluster vertices whereby the electron-deficient center is stabilized by a direct interaction with an organometallic fragment. These calculations also show that replacement of Co(CO)₃ vertices by isolobal CpMo(CO)₂ groups noticeably enhances the stabilization of the silylium moiety. The most successful approach for the synthesis of silylium ions reported to date has been the removal of hybride from a suitable silane precursor. In the attempt to generate a metal-stabilized silylium ion the silane, (CH₃)₃Si-C≅C-Si(C₆H₅)₂H[Mo₂(CO)₄Cp₂], was treated with triphenylmethyl tetrafluoroborate; however, the cluster compound was recovered unchanged. It is apparent from the X-ray structure that the dimetallic cluster and the two phenyl groups inhibit the approach of the trityl for reaction with the Si-H group. The next strategy used in the study involved construction of a tetracoordinate silicon with an alkynyl, two alkyl substituents and a fourth group possessing a reactive site, outside the steric sphere, capable of being removed when treated with the appropriate reagent. In our studies, protonation of an alkynyl-allylsilane (free, or metal-complexed alkyne) with either HBF₄ or triflic acid readily occurs with elimination of propene and formation of the corresponding silyl fluoride or triflate. A competition reaction between free and metal-complexed aklynyl-allylsilanes with a limiting amount of acid showed no discrimination between free alkynes or their metal complexed analogues. The study of precursor compounds which contain both a carbocation site (i.e., alcohol or isopropenyl) and an allylsilane yielded initially the metal stabilized carbocation which subsequently underwent allyl transfer with concomitant formation of a fluorosilane. In contrast, replacement of a a cobalt tricarbonyl vertex by Fe(CO)₃ fragment gave, upon treatment with HBF₄, the corresponding fluorosilane that was characterized by X-ray crystallography.

abstract: Doctor of Philosophy (PhD)


title: Hydrolysis of Storage Proteins in Barley Endosperms: Role of Gibberellic Acid

contributor:
Oaks, Ann B.
Biology

subject: Biology Biology

abstract: The storage proteins in barley endosperms, hordeins, are insoluble in aqueous buffers. During early seedling growth, they are hydrolyzed to small peptides and amino acids. The overall hydrolysis of endosperm reserves is dependent, on enzymes, such as alpha-amylases, carboxypeptidases, and endoproteases, which are induced in response to gibberellic acid. Soluble products released from the hydrolysis of hordeins were analyzed to determine: a) the mode of hydrolysis of these proteins; b) the role of gibberellic acid in the initial hydrolysis of hordein proteins; and finally c) whether the initial events in the hydrolysis are mediated by a specific protease. Soluble proteins were prepared from dry endosperms (controls) and embryo-less endosperm pieces incubated for 24 and 72 hours in a buffered medium in the presence and absence of gibberellic acid. The hordein-related polypeptides in the soluble fraction were identified by using IgG's prepared against urea-denatured hordeins. In the control samples, several bands were detected on western immunoblots. Additional bands in the size range of 25-30 kilodaltons and 40 kilodaltons appeared in the absence of gibberellic acid. In the presence of gibberellic acid, however, fragments in the size range of less than 15 kilodaltons were more dominant. Furthermore, the levels of small peptides (less than 30-35 amino acid residues in length) and free amino acids increased when samples were incubated for longer times in the presence of gibberellic acid. The results are consistent with the idea that a gibberellic acid-independent endoprotease(s) is involved in the initial stages of hordein hydrolysis. Further hydrolysis is, however, dependent on the presence of proteases induced by gibberellic acid. The results are discussed in relation to both the mode of hydrolysis and the specificity of initial events of hordein hydrolysis.

abstract: Doctor of Philosophy (PhD)


title: Shock Wave Propagation through the Pressure Tubes of a CANDU-Type Nuclear Reactor

contributor:
Chang, J. S.
Nuclear Engineering

subject:
Nuclear Engineering
Nuclear Engineering

abstract:
The propagation of weak shock waves through a horizontal stratified two-phase system has been investigated both theoretically and experimentally to demonstrate the various facets of its interaction with the phases, fuel bundles and flow network branches. Two types of shock tubes are used: a lucite shock tube is utilized in monitoring the mechanism at the interface of the phases by high speed photography and the other one is an aluminum shock tube of 101.6 mm inner diameter with flow network branches is used in investigating the shock wave behaviour inside a pressure tube during blow-down and loss of coolant accidents.

This dissertation can be divided in to three broad categories. First, the inclusion of the interfacial roughness factor in the analysis of the shock wave propagation through a two-phase system inside a pressure tube weakens the strength of the shock waves, because of the energy loss due to frictional resistance at the interface. The interface is subjected to a combined effect of the waves propagating both in the gas and liquid phases of the system. High speed photography of the interface is considered to estimate the parameters pertaining to the generation of the ripples at the interface and the coupling of this parameter to a quasi-steady energy balance for the system can provide the values of the magnitude of the overpressures in the system.

Secondly, the interaction of weak shock waves with three different types of fuel bundles used in CANDU reactors is presented. Depending on the percentage of the flow area available, different fuel bundles produce different magnitudes of the overpressure. For the transmitted waves, the choking is markedly observed even for moderate range of the shock waves. Presence of liquid phase enhances the strengths of overpressure for the reflected and transmitted waves. Inside the fuel bundles, the shock waves cause unusual vibrational effects which may be detrimental to the life of the fuel elements.

Around the network, the two-phase propagation velocity is observed to be same as the gas phase propagation velocity is observed as the gas phase propagation velocity. Though tap and distilled water exhibit variations in the maximum overpressures, the time averaged magnitude under these two systems agree very well everywhere in the network branches. The vertical pressure profiles in the tap water has dispersive and high oscillatory nature whereas in the distilled water the rise in overpressure is dispersive, but smooth in nature. In distilled water, the pre-pulses moving under a free surface travel at the speed of sound in water and for those in tap water, this velocity is influenced by the presence of air bubbles in the tube walls.

abstract: Doctor of Philosophy (PhD)


title: An Embedded Temporal Expert for Control of a Tandem Accelerator

contributor:
S., W. F.
Electrical Engineering

abstract: Many process control applications are best solved by heuristic or rule-based control. Unfortunately, conventional expert systems are generally large and slow, centralized on workstation computers, and incapable of continuous operation. Futhermore, few expert systems are able to process time-varying data or to reason about temporal relationships. Thus they are ill-suited to process-control which is inherently a continuous and temporal problem and which increasingly relies upon distributed networks of small embedded processors. A new expert system has been developed to overcome these limitations. This system achieves extremely high inferencing performance on "low end" microcontrollers, and requires very little memory. A new "cooperative/advisory" model of distributed problem solving allows networks of processors to cooperate on a problem while remaining able to work independently on distinct subproblems. Knowledge, in the form of facts or rules, may freely migrate around the network. the system incorporates a new algebra for time-valued data and a formal temporal logic for reasoning about this data. The capabilities of this system were demonstrated by automating for the first time the terminal charging subsystem of a model FN Tandem particle accelerator: a problem which is resistant to an analytic solution. Using the expert system, cooperating 68HC16 microprocessors have successfully operated the accelerator, performing as well, or better than an experienced human operator. During the course of these experiments new techniques for technology insertion were devised and a new local-area network for microcontrollers was invented.

abstract: Doctor of Philosophy (PhD)


title: Kierkegaard on Understanding and Indirect Communication

subject: Philosophy Philosophy

abstract:
Difficult and important interpretative problems arise in a careful reading of Kierkegaard's texts that do not normally arise in reading the texts of authors who go about their writing in a more direct and straightforward. These difficulties are occasioned by Kierkegaard's tactical employment of indirect communication. Indirect communication forces a reader to assume an active and participatory role in the reading of texts. It solicits a special kind of understanding. The kind of understanding it solicits requires effort and concern.

In this thesis Kierkegaard's point of view on understanding is explicated and applied in a reading of his texts. Indirect communication comes into its proper light when thought of as a stratedgy for bringing this sort of understanding about for a given reader. Kierkegaard's views on understanding are used to explain his employment of indirect communication and his views on indirect communication are used to explain his very interesting point of view on understanding.

abstract: Master of Arts (MA)


title: Acquisition and Time Delay Estimates of Canine Gastric Nerve Signals

contributor:
Sinha, N.K.
Daniel, E.E.
Electrical and Computer Engineering

abstract: Approaches to the investigation of myogenic and hormonal controls in the mediation of gut motility are well understood, however methods to analyze neural control remain to be developed. I have developed a cannula system with nerve cuff electrodes, subserosal bipolar electrodes, and extraluminal strain gauges to simultaneously monitor the vagal nerve, myoelectric (ECA), and contractile activities in chronic dogs. The cuff electrodes were used to both stimulate and record nerve signals. Five healthy dogs were implanted with such cannula on the gastric area, with the cuff electrodes placed on the branches of the anterior nerve of Latarjet. The condition of the cuff electrodes were monitored by impedance measurements, while that of the nerves under the cuff electrode were studied by electron microscopy (EM). Three Time Delay Estimation (TDE) algorithms: General Cross Correlation (GCC), Smooth Coherence Of Transform (SCOT), and Maximum Likelihood (ML) methods were simulated with three types of signals as inputs: Band limited Gaussian White Noise (GWN), Sine wave (SINE), and Impulses of random intervals (IMP). Results of the analysis of the recorded neural signals show that the three algorithms can be used to study the sensory and motor patterns of the compound nerve signals with the SCOT and ML methods being superior than the GCC method. The results from the EM studies suggested that the cuff electrode caused loss of the myelinated axons and the larger diameter unmyelinated axons. Based on the results of this study, relevant physiological interpretations were also discussed.

abstract: Doctor of Philosophy (PhD)


title: Adaptive Filtering and Pattern Recognition of Evoked Potentials

contributor:
Bruin, H. de
Electrical and Computer Engineering

abstract: The problem of estimating evoked potentials and its pattern recognition and classification is addressed in this thesis. After providing the relevant physiological background and reviewing the various methods of processing the evoked potential, we propose the method of adaptive noise cancellation for estimating the evoked potential without stimulus repetition. A new weighted exact least squares lattice algorithm is derived for this purpose. The variable weighting factor can be used to make the algorithm robust. Its performance is compared to that of unnormalized and normalized exact least squares lattice algorithms and is shown to be superior. One example of using adaptive noise cancellation to estimate evoked potential without stimulus repetition is presented. Pattern recognition of evoked potentials is achieved by syntactic methods. We derive a finite-state grammar to represent the normal evoked potential. Suitable preprocessing using a zero-phase bandpass filter, parsing and attribute checking are the steps in this classification procedure. A database of normal evoked potentials and optimized acceptance criterion are used for checking the attributes. Detailed training and test runs are performed to demonstrate the performance of this classifier.

abstract: Doctor of Philosophy (PhD)


title: Reciprocity and Exploitation: Peasant Women in Malaysia's Industrialization Process

contributor:
Cooper, Matthew
Anthropology

subject: Anthropology Anthropology

abstract: The case of Malaysia as an industrializing country is contrary to the predictions of world systems theory. The ethnic imperatives of the state's New Economic Policy has necessitated the successful manipulation, and accumulation, of foreign and domestic capital for the economic development process. Although Malaysia enjoys an impressive rate of growth, the way in which the benefits are allocated by the state elite has resulted in the increased economic inequality of the labour force. The fact that development is taking place is partly the result of the 'exploitation' of the labour force which, in Malaysia's development process, remains rooted firmly in, and dependent upon, the non-valorised 'reciprocal' labour of kin. Exploitation and reciprocity are developed as a conceptual framework within which the field is analyzed. The dissertation examines the way in which reciprocity - a multidimensional phenomena - is utilised at different levels of Malaysia's development process. Reciprocal obligations link peasant households to the production processes of state and foreign capital. The study draws particular attention to the position of young Malay women who work in transnational corporations producing goods for international markets and in household subsistence production. The gender specific nature of Malaysia's industrial labour force dictates that it receives few benefits from state prosperity. The way in which the work force survives by 'occupational multiplicity' in the interstices of industrial wage labour, 'reciprocity' and subsistence production, forms the theoretical and empirical focus of the dissertation. Malaysia's new semiproletariat sustain themselves and their households in subsistence production by an amalgamation of intra and inter household reciprocity. In this way their non valorised labour contributes to the State's New Economic Policy.

abstract: Doctor of Philosophy (PhD)


title: Modelling the Competitive Adsorption of 1,1,2-Trichloroethane with Naturally Occurring Background Organics onto Activated Carbon

contributor:
Benedek, Andrew
Chemical Engineering

subject:
Chemical Engineering
Chemical Engineering

abstract:
Activated carbon adsorption is the most widely considered process for the removal from drinking water of low level toxic chemicals as well as many other organic substances. The adsorption of these compounds involves complex competitive interactions which are not well understood, however, they are crucial to the design of safe and cost effective adsorbers. To obtain a better understanding of competitive adsorption as observed in water treatment adsorber, at the time of a toxic spill, a three part study was conducted with a representative bisolute mixture. The mixture consisted of a toxic chemical (1,1,2-trichloroethane (TCEA)) and the naturally occurring organic substance from a northern river considered as a single compound and measured as TotaI Organic Carbon.

The first part of this study consisted of single solute adsorption and desorption experiments as well as blsolute equiIibrium experiment. The adsorption of TCEA was found to be completely reversible, while that of the background organics was virtually irreversible. The bIsolute experiments showed that the background organics substantIally decreased the adsorption capacIty of TCEA, while the adsorption capacity of the background organics was only marginally reduced by the presence of TCEA. The predictive multisolute Isotherm models in the literature could not describe the experimental data. Two other models, which assume that a fraction of the adsorption does not involve competition, were found to describe the data successfully.

The second part of this study investigated the rates of adsorption from one-adsorbate and two-adsorbate soIutions. The data of both single adsorbate kinetic experIments were described very well by the homogeneous surface diffusion model. The adsorption of the background organic was very slow, yet it was not necessary to utilize separate terms for the slow and rapid adsorption mechanisms. All of the adsorption occurred by the slow mechanism. The slow adsorption phenomenon, which is suspected to occur in very small pores, appears to be related to the irreversible adsorption observed during equilibrium studies. The background organics that adsorbed by the slow mechanism were virtually not desorbable, while TCEA which adsorbed completely reversibly, did not show any slow adsorption during the kinetics. As expected from the large difference in the values of the diffusion coefficients, to properly model the bisolute batch kinetic experimental data, diffusional interactions such as cross diffusion terms had to be included.

The third part of this investigation was a column study involving six different phases, each with a different feed solution. The results were consistent with the equilibrium predictions. Phase IV showed that an expected and potentially dangerous large scale desorption of previously adsorbed toxic organics, caused by a substantial increase in the feed background organics, did not occur. The elution of TCEA actually decreased, probably due to cross diffusional interactions. The column experiment also confirmed that due to competitive interactions and to the increasing loading of background organics on the carbon with time, the adsorbers became substantially less effective at treating toxic spills as the operation cycle proceeded.

abstract: Doctor of Philosophy (PhD)


title: Power and Spectral Characterization of InGaAsP-InP Multi-Quantum Well Lasers

contributor:
Simmons, J. G.
Engineering Physics

subject:
Engineering Physics
Engineering Physics

abstract: A detailed study is presented of power and spectral measurement methodology commonly used to characterize and optimize the fundamental continuous-wave properties of semiconductor lasers. These properties include: efficiency, optical loss, the temperature sensitivity of threshold, gain, and spectral linewidth. The techniques studied are found to often yield erroneous or misleading results. The conditions under which errors can occur are investigated and precautionary measures necessary to avoid these problems are outlined. The effect of well number, length, and temperature on efficiency and optical loss is investigated. A phenomenological model based on inter-valence band absorption (IVBA) for the description of the results is developed. The model provides evidence of the importance of IVBA in determining laser characteristics, including the failure to lase. The operating regime where IVBA dominates is found to be clearly identifiable. It is also found that, in the presence of IVBA, there exists a poptential for misleading measurements of the internal efficiency and the optical loss. Using the high temperature sensitivity of the gain coefficient, it is possible to obtain an indication as to whether IVBA is affecting the experimental results. In order to study the temperature dependence of the threshold current, a derivation of the empirical Tmax relation is given which provides meaning to the fitting parameters. The experimentally determined Tmax is shown to correlate with the Tmax predicted from data obtained by the IVBA model for a range of lengths and well numbers. The conditions under which the Tmax relation is valid are determined. The gain coefficient for lasers having five quantum wells is calculated theoretically and compared to the gain coefficient obtained experimentally both from the IVBA model for efficiency and from the length dependence of the threshold current density. The efficiency method agrees with theory to within experimental error. However, the threshold method yields a value which is approximately one-half of the theoretical value, a phenomenon which has been previously observed in the literature but for which no explanation has been found. Direct measurement of the below-threshold output spectrum of the lasers demonstrates that the cause of this discrepancy is an unexpected length dependence of the gain coefficient. Non-uniform carrier injection into the quantum wells is suggested as a possible physical mechanism. A potential for gross inaccuracies in the measurement of laser linewidth using the delayed self-homodyne (DSH) technique is discovered. It is found that the accuracy of the DSH technique depends on the amount of noise in the laser bias current source to a previously unappreciated degree. This is due to a combination of the high FM sensitivity of semiconductor lasers and the long optical delay lines required by the DSH technique. The errors behave in a manner usually associated with intrinsic 1/f noise, and can cause all of the associated properties of residual linewidth, floor, non-Lorentzian lineshape, and premature re-broadening of the laser line. Guidelines for proper filtering of the current source are given to ensure accurate measurements.

abstract: Doctor of Philosophy (PhD)


title: Centralised Time Series Management for Continuous Hydrology on Personal Microcomputer Networks

contributor:
James, W.
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract:
Continuous hydrology packages such as Hydrologic Simulation Program--Fortran (HSPF) and Version 3 of the Storm Water Management Model (SWMM3) require extensive computing time even for certain cases of event modelling. In their original sequential, time-sharing, computing schemes, continuous modelling applications required a prohibitively expensive overall turn-around time and an overwhelming amount of manual Input/Output (I/O) time series (TS) data management effort. By decentralizing the processing, avoiding a time-sharing computing environment, and finding ways to keep track of I/O TS data as part of the processing, these problems can be overcome.

Computational Hydraulics Group Time Series Manager (CHGTSM), a Database Management System (DBMS), was developed by the present author to provide easy access to TS data, independent of details of storage. CHGTSM is based on an unconventional data access technique, also developed by the author, that handles variable resolution continuous TS records. The CHG Time Series Store (CHGTSS) is prepared by the CHGTSM. CHGTSM is applied succesfully. In a case study, CHGTSM saved 88% in hard disk storage compared to the raw database. CHGTSM serves event as well as continuous modelling applications. A manual for CHGTSM is also written by the present author.

CHGTSM can be used to distribute the database to the nodes of a linked configuration of microcomputers. Distributed processing (DISP) of centralized data is made possible by CHG Distributed Data Processing Software (CHGDPS). CHGDPS, developed by the present author, is a shell around CHGTSM which includes security provisions and node synchronization assistance. The simulation of a DISP application for continuous hydrologic modelling in a Local Area Network (LAN) improved the computing efficiency by 54% compared to sequential processing. CHGDPS will allow true concurrency only through a batch application.

CHGDPS synchronization assistance relies on timing relations of the computational modules that are accessing the system. A program measurement (PM) technique was adopted, enhanced and applied by the present author to obtain the timing relations. Such DISP control helps the user to optimize overall system processing. For example, CHGDPS may decide (or help decide) a shift from one computational approach to another for considerations of time, space, numerical stability, and accuracy.

The DISP scheme is flexible and can be implemented on any linked configuration of computers e.g. LAN' s, distributed data gathering and real time control (RTC) devices. The whole system, called the Computational Hydrology Work Group System (CHWGS) is assessed as an environment for continuous (or event) hydrologic modelling, distributed data gathering and distributed RTC.

abstract: Doctor of Philosophy (PhD)


title: PROSTAGLANDINS, CYCLIC AMP AND HUMAN PLATELETS

subject:
PREINCUBATION
CYCLIC
PLATELETS
LEVELS
AMP
INHIBITOR
Medical Sciences
Medical Sciences

abstract: Master of Science (MS)


title: Mal'uocchiu: The Sicilian-Canadian Evil Eye Complex

contributor:
Rodman, William L.
Anthropology

subject: Anthropology Anthropology

abstract: Throughout the thesis, I examine the interrelationship between illness and the Sicilian-Canadian notion of evil eye (mal'uocchiu). Based on an analysis of evil eye beliefs and actual case histories of victims of mal'uocchiu, I arrive at the following conclusion: the illness/evil eye interrelationship involves a stress generating discrepancy between an individual's personal expectations and what actually takes place. This discrepancy may, in certain cases, cause physical symptoms. I discuss the implications of my work for evil eye, witchcraft and folk illness studies.

abstract: Master of Arts (MA)


title: Classically Bonded Chalcogenide Anions of Tin, Thallium, and Lead in Basic Media

contributor:
Schrobilgen, Gary J.
Chemistry

subject: Chemistry Chemistry

abstract: This Thesis describes the preparation of classically-bonded chalcogenide anions of tin, thallium, and lead in basic media and their structural characterization in solution by multi-nuclear magnetic resonance (multi-NMR) spectroscopy and in the solid-state by single-crystal X-ray crystallography and vibrational (Raman) spectroscopy. The Sn₂Ch₆⁴⁻ and Sn₂Ch₇⁴⁻ (Ch = Se, Te) anions have been characterized in solution for the first time by multi-NMR spectroscopy. The magnitudes of the relativistically corrected reduced coupling constants ¹K(Sn-Cht)RC, ¹K(Sn-Chmb)RC, and ¹K(Sn-Chdb)RC were shown to be consistent with a significant degree of s-character in the bonding. The Sn-Chmb and Sn-Cht bond distances observed in the X-ray crystal structures of the Sn₂Ch₆⁴⁻ anions were shown to correlate with the ¹K(Sn-Cht)RC values, indicating that the solid-state molecular structures of the anions are retained in solution. The Raman spectra of the Sn₂Ch₆⁴⁻ anions are also reported along with their respective factor-group analyses. The novel HOSnTe₃³⁻ anion, the hydroxide derivative of SnTe₃²⁻, has been structurally characterized by X-ray crystallography and represents the first example of a simple mixed hydroxychalcogenide anion of tin. The novel of Sn₄Ch₁₀⁴⁻(Ch = Se, Te) have been characterized for the first time in solution by ⁷⁷Se, ¹¹⁹Sn, and ¹²⁵Te NMR spectroscopy and in the solid-state by X-ray crystallography and Raman spectroscopy. The solid-state and solution anion geometry is of the adamantanoid type where the Snᴵᵛ atoms occupy the bridgehead position and the Ch atoms occupy the bridging and terminal sites. The Raman spectra of the Sn₄Ch₁₀⁴⁻ anions have been assigned and compared with those of related adamantanoid systems and SnSe₄⁴⁻. The X-ray crystal structure of the novel adamantanoid Sn₄Se₉⁴⁻ anion is also reported and represents the first example of a P₄O₉-type post-transition element anion containing tin and a chalcogen. The solution and X-ray crystal structure of the TI₂Te₂²⁻ anion and the vibrational spectra of the TI₂Ch₂²⁻ (Ch = Se, Te) anions have been determined. Density functional theory calculations at the local and nonlocal levels confirm that the butterfly geometries observed in the solid state are true minima in the gas phase but are highly deformable. This finding is supported by the variation of the ²⁰⁵TI-²⁰³TI spin-spin coupling constants in the TI₂Ch₂²⁻(Se and/or Te) anions with solvent and temperature and by the observed and calculated low vibrational frequencies of the anion inversion modes. Theory indicates that the TI-Ch bonds are essentially pure p in character and a significant concentration of s-electron density along the TI∙∙∙TI axes and is supported by the small magnitudes of ¹K(TI-Ch)RC and the large magnitudes of K(TI-TI)RC observed for the TI₂Ch₂²⁻ (Ch = Se and/or Te) anions in solution. The series of Group 14 metal trigonal bipyramidal M₂Ch₃²⁻ (M= Sn, Pb; Ch = S, Se, and/or Te) anions has been extended to the mixed-metal TIMTe₃³⁻ (M = Sn, Pb) anions which were characterized in solution by ¹¹⁹Sn, ¹²⁵Te, ²⁰⁷Pb, and ²⁰⁵TI NMR spectroscopy. The TIPbTe₃³⁻anion was also characterized by X-ray crystallography in the compound (2,2,2-crypt-K⁺)₃TIPbTe₃³⁻∙2en. The small magnitudes of ¹K(M-Ch)RC observed for M₂Ch₃²⁻ and TIMTe₃³⁻are consistent with predominantly p-bonded cages and is supported by local and nonlocal density functional theory calculations which indicate that the experimental structures are true minima. Although theory indicates weak M∙∙∙M interactions of high s orbital character on M, the large K(M-M)RC and K(TI-M)RC couplings appear to arise predominantly from multiple coupling pathways and can be rationalized in terms of the small M-Ch-M bond angles observed in the X-ray crystal structures. The novel TI₂Seᵪⁿ⁻, TI₃Seᵧᵐ⁻, and TI₃Sezᴾ anions have been obtained by extraction of the alloys NaTISe and NaTI₀.₅Se in en and liquid NH₃ in the presence or absence of 2,2,2-crypt and characterized by variable-temperature ⁷⁷Se, ²⁰³TI, and ²⁰⁵TI NMR spectroscopy. Although the detailed solution structures of the anions have not yet been determined, they were shown by an analysis of the TI-TI spin-spin coupling patterns and the ²⁰³TI and ²⁰⁵TI subspectra arising from natural abundance isotopomer distributions to be di- and trinuclear with respect to thallium. The X-ray crystal structures of the novel TI₄Se₈⁴⁻ and [TISe₄/₂⁻]¹ anions are also reported and represent rare examples of thallium selenide polyanions.

abstract: Doctor of Philosophy (PhD)


title: Adaptive Detection for Radar

contributor:
Haykin, S.
Electrical Engineering

abstract:
A new adaptive procedure for the detection of a random signal in a background of colored interference plus white noise, all having unknown statistics is derived. The procedure is based on the development of linear models for the two hypotheses H₀ and H₁. Under hypothesis H₀ a wanted signal is absent and under H₁ the wanted signal to present. After parameterizing the input signal under the two hypotheses, the log likelihood ratio is easily established in terms of the innovations processes. The test statistic thus obtained has an intuitive interpretation, which conversely provides a basis for the choice of model candidates for the signal detection problem. Different modelling approaches generally result in different receiver performance. Therefore, choosing appropriate type of model for the two pypotheses is a key step in order to enhance detection. A computationally efficient technique has been developed for this purpose.

This adaptive detection method is applied to construct a radar detection scheme for detecting a moving target in a surveillance radar environment. The detector is composed of a pair of adaptive whitening filters followed by a log likelihood ratio calculator. The new scheme is tested by using actual radar data, including weather and ground clutter. Comparison is made with the previously described scheme known as innovations-based detection algorithm (IBDA). The results show that the performance of the new scheme is much better than the IBDA.

In a related study, the spatial correlation between radar clutter from adjacent rings is exploited to construct two new adaptive clutter suppression schemes. The schemes are tested by real radar data. Experimental results show that these schemes are around 5 dB and 10 dB better than the adaptive lattice prediction-error filter in terms of improvement factor, respectively.

abstract: Doctor of Philosophy (PhD)


title: Study of the excited states of ⁶⁰’⁶¹Zn

contributor:
Cameron, John A.
Physics

subject: Physics Physics

abstract:
The level structures of the nuclei ⁶⁰Zn and ⁶¹Zn have been studied by means of (τ,nϒ) and (α,nϒ) reactions, respectively. Additional heavy ion induced reactions were also investigated with respect to ⁶⁰’⁶¹Zn and other competing channels, notably ⁵⁹Zn , ⁶⁰Cu and ⁶¹Ga. Gamma singles, n-ϒ coincidence, ϒ-ϒ, multi-y coincidence, ϒ and n-ϒ angular distribution measurements were made. Limitations on excited state lifetimes were obtained from beam pulsing, electronic timing, and Doppler shift measurements. A high resolution neutron spectrum of the ⁵⁸Ni(α,n)⁶¹Zn reaction was obtained. Attempts at other multi-particle transfer experiments have been unsuccessful.

The experimental results are compared with those found elsewhere and with theoretical calculations.

abstract: Doctor of Philosophy (PhD)


title: Robust Identification of Dynamic Systems

contributor:
Sinha, N. K.
Electrical Engineering

abstract:
The problem of identification (estimation of system parameters and characteristics) is considered. The aspect emphasized is the robustness in identification. By saying robustness, two points are meant. One is the robustness with respect to bad pieces of data and the other is the numerical robustness with respect to truncation and round-off errors in computation.

A thorough study has been made on the robust statistical principles and their applicability in system identification is critically evaluated. Off-line and on-line identification algorithms are proposed, which are resilient to undetectable spurious errors in the data and at the same time computationally simple and efficient. The convergence of these algorithms is theoretically established. Besides, a robust recursive algorithms is also proposed which jointly estimates the states and parameters of a linear system in a bootstrap manner. This algorithm is also proven to be converging with probability one. In addition to this, a very general method is developed for evaluating the asymptotic efficiency of robust identification methods. The superiority of the proposed approaches in contrast with the conventional identification methods (least squares and its genaralizations) is illustrated with the help of several simulated as well as real-life examples.

The numerical instability caused by improper choice of sampling rates is also subjected to considerable study in the context of identification of continuous-time systems from samples of input-output data. Methods are suggested to overcome this problem. Also, numerically robust schemes are introduced for transforming discrete-time models to their continuous-time equivalents and their performance is compared with other existing methods.

abstract: Doctor of Philosophy (PhD)


title: Adaptive Control of Multivariable Systems via Pole Assignment

abstract: The adaptive control of linear discrete time multivariable systems is considered. A unifying survey of a number of adaptive control strategies is presented. The various algorithms are shown to be special cases of a more general algorithm. The state space design of self-tuning controllers is considered in detail. Two new algorithms for state space pole assignment self-tuning control are proposed. The first algorithm follows an explicit approach, thus a modification of the bootstrap estimator was used for joint parameter and state estimation of an innovations model. The resulting self-tuning controller is more efficient computationally than the methods based on block canonical forms since a minimal realization can be adopted. The second algorithm may be regarded as an implicit pole assignment controller. The recursive prediction error algorithm is used for joint parameter and state estimation in the controller canonical form. The main contribution of this approach is that on-line computation of transformation matrices is avoided. The subsequent computation of controller parameters is trivial, and the resulting self-tuning controller is robust to over-parameterization. To demonstrate a practical application, the second algorithm was used to design a robust autopilot for a simulated nonlinear model of a Royal Navy frigate subjected to sea disturbances. The autopilot was found to perform well for both the course keeping and course changing modes.

abstract: Doctor of Philosophy (PhD)


title: Supply Side Effects of Monetary Policy

contributor:
Scarth, William M.
Robb, Leslie A.
Magee, Lonnie J.
Economics / Economic Policy

subject: Economics Economics

abstract:
The primary purpose of this thesis is to combine two branches of empirical work concerning firms demands for factors. One set of studies involves the simultaneous estimation of money, labour and capital demand functions, where the focus is on the role of money as a factor production, and adjustment costs for capital are ignored. The other set of studies involves estimation of an investment function, together with other factor demand functions. Writers in this area typically exclude money as factor in the production process, though we wish to overcome that omission in this thesis.

We also study the possible supply side effects of monetary policy that arise because of the role of money as a factor of production and deduce macroeconomic policy implications.

Our empirical work is divided into three stages. In each stage we assume that firms minimize the cost of producing a given level of output subject to a production function that includes real money balances as a factor input. In the first stage we estimate a full equilibrium model in which firms can adjust their capital stocks without any lags and there are no costs associated with the adjustment of these capital stocks. In the second stage of estimation we introduce the fixity of capital stocks in the short-run into the firms' optimization problem. In this temporary equilibrium model, costs of adjustment of capital are not assumed. Finally, we estimate a dynamic model of the firm based on the assumption of non-linear internal costs of adjustment for capital. The three empirical models are estimated at the aggregate level for non-financial corporations in the United States.

On statistical grounds the full equilibrium model did not fit the data well. The own price elasticity of real money balances was not significantly different from zero. In the other two models, where capital is fixed in the short-run, all the own price elasticities are significantly different from zero and have negative signs. Furthermore, in the full equilibrium model, autocorrelation seemed to be present even after making a first order correction for the errors.

The temporary equilibrium model was also statistically rejected, conditional on the particular functional form of the cost function employed in the dynamic model. We conclude that the dynamic specification is most appropriate in this context.

The price elasticities varied substantially across the different models. The cost minimizing interest rate elasticity of labour demand was significantly different from zero and negative in sign in the dynamic model. However, the implied profit maximizing interest rate elasticity of labour demand was not statistically significant. This suggests that earlier estimates of money's role in the production process were contaminated by the restriction that there were no costs of adjustment.

abstract: Doctor of Philosophy (PhD)


title: La Condition de la Femme dans les Oeuvres de Maryse Conde

contributor:
Warner, G.
French

subject: French and Francophone Language and Literature

abstract: Dans cette thèse nous analyserons le problème de la domination des hommes sur les femme, à travers les actions des personnages (hommes/femmes) dans les pièces et le romàn de Maryse Condé. Nous examinerons aussi l'évolution de la prise de conscience des femmes qui mène aux premiers pas de la révolution personelle des femmes.

abstract: Master of Arts (MA)


title: Stray Load Losses in Induction Machines

contributor:
Findlay, R. D.
Electrical and Computer Engineering

abstract:
Understanding and minimizing loss are the main objectives of seeking solutions to the problems of stray loss in induction machines. This thesis contributes towards this objective by addressing the various problems of stray load loss. These problems include the questions of definition, origin, components, and effects; theoretical and experimental means of evaluation; and loss reduction.

Insights into these problems are achieved through a comprehensive review of the state of the art of the subject. We have established that some commonly used terminologies in the subject area formed major obstacles to progress in definition.

A conceptually simple and general theory of squirrel cage induction machines is presented. The theory results in a set of linear periodic differential equations, which has an infinite number of possible solutions. A suitable solution procedure is developed.

Means for accounting for slot openings and saturation are developed. These have enabled various field waveforms in a practical machine to be generated and analyzed. The analysis produced insights into the interactions of harmonics and how harmonics contribute to stray load losses. Through this, an approximate means of separating a saturated non-sinusoidal waveform of an air gap flux density waveform into its fundamental, saturation, and other space harmonics is developed. An expression for determining the machine torque is derived. This torque expression, the ideas for manipulating and analyzing the field waveforms, and the presented theory are structured into an algorithm, modeling the behaviours of squirrel cage induction machines. The algorithm enabled the torque-speed characteristic of a practical machine to be predicted.

The predicted characteristic is compared with that measured by means of accelerometer. The fact that it compares very well validates the theory and the developed model. The new steady state model has several advantages, including its easy application to the study and the evaluation of stray load losses. A brief study of how harmonics influence the developed torque is also conducted using the new model.

Two theoretical methods are developed for predicting stray load loss at the design, manufacturing, or utilization stage of a machine. These methods, which employ the developed model, are applied to a practical machine.

The predicted stray losses are compared with the measured, and that predicted using the nominal assignation technique. This draws attention to the need for experimental investigation of the subject. Consequently, two experiments, calorimetric method and novel experiment to study inter-bar current problem, are developed. Due to technical and economic problems, however, their implementation are not yet completed.

abstract: Doctor of Philosophy (PhD)


title: Endurance Training In Elderly Males

contributor:
Jones, N. L.
Heigenhauser, G.J.F.
Medical Sciences

subject: Kinesiotherapy Kinesiotherapy

abstract:
Twelve 60-70 and ten 20-30 year old sedentary healthy males participated in this study to determine the effects of endurance training in improving the exercise capacity of elderly individuals and to examine the mechanisms related to oxygen transport that may contribute to any such change. Oxygen intake (VO2), CO2 output (VCO2), ventilation (VE), heart rate, blood pressure, cardiac output, and the ability of muscles to generate short-term power were measured during exercise before and after twelve weeks of high intensity endurance training.

Before training, the elderly had a 37% lower peak VO2 then the young subjects, associated with lower peak cardiac output, and arterio-venous oxygen ((a-v)O2) difference, heart rate and stroke volume and a lower vascular conductance. The capacity to generate short-term power was also about 30% lower in the elderly.

After training, peak VO2 (1/min) increased from 1.599 ± 0.073 to 2.212 ± 0.093 (38Z) in the elderly and 2.536 ± 0.141 to 3.263 ± 0.181 (29Z) in the young. Although the extent of the improvement was similar, different mechanisms contributed to the improvement in the two groups.

Firstly, in the elderly, peak cardiac output (1/min) increased from 12.7 ± 0.6 to 16.5 ± 0.4 (30%); the (a-v)O2 difference (ml/l) increased only by 6% (126.5 ± 3.7 to 134.7 ± 2.7). In the young, there were equal increases in cardiac output (a-v)O2 difference (14%). Secondly, the increase in peak cardiac output in the elderly was accompanied by a marked increase in peak stroke volume (78.9 ± 3.5 to 95.6 ± 2.5 ml, 21%), with a smaller but significant increase in peak heart rate (161 ± 3.8 to 173 ± 3.9 beats/min, 7%); in the young, stroke volume and heart rate increased to a similar extent (9% and 5% respectively). In addition, significant increases were observed after training in the elderly in submaximal stroke volume, cardiac output and vascular conductance; their systolic blood pressure during submaximal exercise was significantly lower. There were no changes in the young group. The changes in short-term power output were similar in both groups; total work increased by 13% in old and 8% in young, associated with decreases in plasma lactate and muscle fatigue. These changes together with decreases in the RER suggest improved aerobic metabolic processes in muscle.

In conclusion, elderly individuals respond to high intensity endurance training by increases in peak VO2 that are of the same magnitude as in young subjects. Marked training-associated increases is submaximal and peak stroke volume and cardiac output in the elderly are accompanied by decreases in heart rate, systolic blood pressure and increases in vascular conductance. These changes suggest improvement in the perfusion of exercising muscles which enabled these trained elderly to achieve higher levels of exercise and peak VO2.

abstract: Doctor of Philosophy (PhD)


title: Topics in One-Dimensional Magnetism

contributor:
Collins, M.F.
Physics

subject: Physics Physics

abstract:
An experimental study of the dynamic properties of the quasi-one-dimensional magnetic materials CsMnBr₃ and CsMn₀.₈₉Fe₀.₁₁Br₃ has been carried out. In addition, some theoretical and computer simulation work was performed on aspects of the static behaviour of selected one-dimensional magnetic systems.

CsMnBr₃ is a one-dimensional magnetic insulator. Its magnetic behaviour can be described by a Heisenberg antiferromagnetic chain system with weak easy plane anisotropy. A truly one-dimensional system cannot sustain long-range order at any non-zero temperature, although short-range correlations can be strong at low temperatures. We used neutron scattering techniques to examine both the delocalized (spin wave) and localized (soliton) excitations of CsMnBr₃ in its paramagnetic phase at low temperatures. Our results of the spin wave response compare favourably with recent theory of co-operative excitations in the absence of long-range order. Our measurements of the soliton response is in qualitative agreement with the relevant theory. Soliton-like spin configurations could also be directly observed in the results of a Monte Carlo simulation on a system representative of CsMnBr₃.

We also used the Monte Carlo method to examine static spin correlation lengths within the XY to Heisenberg crossover temperature regime in CsMnBr₃.

We measured the magnetic excitation spectrum of the magnetic impurity chain system CsMn₀.₈₉Fe₀.₁₁Br₃ at low temperatures by neutron scattering techniques. The response was qualitatively different from either CsMnBr₃ or previously studied magnetic vacancy chain systems and showed marked host mode-impurity mode interaction effects.

Finally we utilized the computational ease afforded by one dimension to examine the strengths of biquadratic exchange interactions in selected Mn⁺² chain systems, including CsMnBr₃.

abstract: Doctor of Philosophy (PhD)


title: GC/MS Examination of Lycopodium Extracts for Alkaloid Content

contributor:
MacLean, D.B.
Chemistry

subject: Chemistry Chemistry

abstract:
Plants of the Lycopodium species have long been known to elaborate alkaloids. Over one hundred alkaloids have been isolated from these plants, but no efficient method exists to quickly screen plants to determine their alkaloid content. In this research it has been found that gas chromatography mass spectrometry. (GC/MS) is a suitable method to achieve this purpose. Seven species of Lycopodium were examined; L. australianum, L. scariosum, L. fastigiatum, L. deuterodensum, L. clavatum var.borbonicum, L. flabelliforme and L. Jucidulum, of these L. australianum, L. scariosum and L. fastigiatum have been examined for the first time in this research. New alkaloids were found in some of the species examined. Two new alkaloids, des-N-methylfastigiatine and fastigiatine, were isolated from L. fastigiatium and their structures determined by X-ray analysis. Since these alkaloids represent a new ring system extensive mass spectrometric and nuclear magnetic resonance experiments were undertaken.

A data base of the mass spectra of known Lycopodium alkaloids was compiled and found to be useful in computer searches of GC/MS data for the identification of known alkaloids. Chemical ionization mass spectrometry with methane as the reagent gas was found to provide information on some of the functional groups present in the Lycopodium alkaloids.

abstract: Doctor of Philosophy (PhD)


title: A Parametric Approach for Spectrum Analysis and Carrier Frequency Estimation of Search and Rescue Satellite-Aided Tracking (SARSAT) Signals

contributor:
Carter, C.R.
Electrical and Computer Engineering

abstract:
This thesis deals with the analysis of emergency locator transmitter (ELT) signals used for locating crash sites of aircraft or ships through the Search and Rescue Satellite Aided Tracking (SARSAT) System. This system uses the doppler shift phenomenon to achieve its goal.

Experiments conducted by the Communications Research Centre (CRC) in Ottawa, discovered problems associated with a family of ELT units produced by certain manufacturers. One of the major problems is the random-phase characteristic of these ELT signals, producing bad spectra, where the doppler shift cannot be easily estimated.

In this thesis, the performance of different processors, including the Periodogram (FFT) and the autoregressive moving average (ARMA) method, is investigated as applied to estimating the spectrum of ELT signals. The spectrum is used to obtain the doppler shift. Results of processing computer-generated signals and real test ELT signals indicate the inefficiency of the FIT for random phase signals. However, low order ARMA models are seen to be more effective.

A novel processor is suggested here for handling the random-phase signals. This processor is based on a new approach (proposed here) for carrier frequency estimation of signals, using low order MEM or ARMA. Not only is random phase problem solved, but also simplified processing and more accurate results can be achieved.

abstract: Doctor of Philosophy (PhD)


title: Development and Characterization of a Human Adenovirus Type 5 Cloning Vector

contributor:
Graham, Frank L.
Biology

subject: Biology Biology

abstract:
This thesis describes studies designed to develop and utilize human adenovirus type 5 (Ad5) as a cloning and expression vector in mammalian cells. The experimental approach taken in this work was first to determine the limits on the amount of DNA which could be packaged into virion capsid. To this end I have used mutants of Ad5 derived from insertion of a bacterial transposable element (Tn5) into the left end (the transforming region) of the viral genome. Attempts to rescue various sized derivatives of these Tn5 insertion mutants into full length infectious Ad5 DNA indicated that not more than about 2 kb of insert DNA could be rescued in this way. To extend this limit, a helper-independent Ad5 cloning vector has been constructed in which most of early region 3 (E3), from map co-ordinates 78.5 to 84.7, and essentially all of early region 1 (E1), from 1.0 - 10.6, have been deleted. E3 is non-essential for adenovirus replication in cultured cells and E1 is non-essential when the virus is propagated in 293 cells which constitutively express the E1 gene products. The resulting new virus, d1E1,3 was about 5.5 kb shorter than wt Ad5 and therefore should be able to accept up to 7.5 kb in foreign DNA. To test the usefulness of this vector, the Herpes Simplex Virus type 1 (HSV.1) thymidine kinase gene (tk) along with its regulatory sequences was inserted into the unique Xbai site of d1E1,3 (at map position 78.5/84.7). The resulting recombinant virus, Adtk, expressed the HSV tk at a low level (as compared to levels induced by HSV.1) in infected cells; however, tk expression was markedly enhanced when Adtk infected cells were super-infected with a tk mutant of HSV. Furthermore, the Adtk virus efficiently transformed tk⁻ mouse cells (line K4 and its progenitor the LTA) to the tk⁺ phenotype. At a low efficiency, it was also possible to transform tk⁻ human cells (line 143), and tk⁺ transformants of both mouse and human origin have been established as permanent lines.

Lastly, during construction of d1E1,3, we isolated a variant, d1E1,3-1, which had a direct repeat of viral DNA terminal sequences attached to the left end of the genome. Analysis of this variant with restriction enzymes and by hybridization of Southern blots with specific probes indicated that the extra terminal segment contained the left 2.6%(920 bp) of Ad5 joined to 352 bp of pBR322 which in turn was linked to the left end (minus 21 bp) of d1E1,3. During replication of d1E1,3-1 the extra terminal segment was found to transfer to the right end of the genome resulting in a second variant, d1E1,3-2, having duplicated terminal sequences at both ends of the viral genome. D1E1,3-2, was shown to revert back to d1E1,3-1 at high frequency. Although evidence was obtained indicating that the extra segment could be lost from the left end at low frequency, spontaneous mutants which had lost direct repeats from both ends were never isolated. It was, however, possible to remove the extra terminal repeat of d1E1,3-1 by cleavage with a restriction enzyme and to isolate d1E1,3 containing wt termini. The rearrangements occurring during replication of d1E1,3-1 and d1E1,3-2 may be the consequences of the mode of replication of Ad5 DNA.

abstract: Doctor of Philosophy (PhD)


title: Blacks in Hamilton: An Analysis of Factors in Community Building

contributor:
Shaffir, William
Sociology

subject: Sociology Sociology

abstract: This study, which is based on field research, examines the question of ethnic community formation among Blacks in Hamilton. It deals with both the factors, such as institutions or voluntary organizations, which facilitate community building and those, such as the absence of effective local Black leadership, which undermine that endeavor. Given the limited number and range of formal institutions or organizations in the local Black community, this study concentrates on the informal channels of interaction among local Blacks. The major informal channels identified and examined are as follows: (1) dinners and dances; (2) picnics; (3) the annual Cari-Can summer festival; (4) Martinsday celebrations; (5) Black History celebrations; and (6) house parties. This study found that there are two primary reasons for the appeal of informal features of Black communal life; (1) they offer Blacks opportunities to be overtly Afro-centric and (2) unlike formal organizations, they do not demand long-term commitments. Another major finding of this study is that Black ethnic identity in Hamilton is significantly stronger than one would expect based on the institutional strength of the local Black community. This identity is more directly related to ideologies and events among Blacks in Toronto, the United States, and elsewhere than it is to local circumstances.

abstract: Doctor of Philosophy (PhD)


title: Pavement Deflection Analysis Using Stochastic Finite Element Method

contributor:
Stolle, D.F.E.
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract: In order to assess the structural charateristics of a pavement-subgrade system, non-destructive, in-situ tests together with backcalculation procedures are widely used. Traditionally, the analytical models adopted for this proccess are deterministic, however, in reality, the quantities involved in the problem may be random variables. Neglecting the variable nature of the system parameters, e.g., highway material properties, may affect the reliability of the pavement response prediction. On the other hand, inverse solutions to pavement problems are often ill-conditioned and sensitive to the input parameters. Past experience has shown that the estimated values of a blackcalculated parameter by different agencies may vary by several orders of magnitude, representing a high level of uncertainty in the estimated paramter. Unless the uncertainty is quantified, practitioners are forced to resort to higher safety factors, which is neither economical nor always conservative. The present study investigates, rigorously, the behavior of a pavement-subgrade system from a stochastic point of view, and addresses the sensitivity of response variation to variations in layer properties. The results of a forward analysis are utilized to establish a relation between input and output statistical moments in order to interpret the pavement deflection data stochastically. The proposed framework in this research allows one to quantify the uncertainty level in backcalculated system parameters. It also provides a tool to infer the accuracy of the pavement performance prediction based on mechanistic models. For the purpose of introducing the stochastic approach, the perturbation technique is applied to an idealized, two-layered, pavement-subgrade system for the case of: (a) a static solution based on Odemark definition of equivalent layer thickness; and (b) a frequency domain solution to a single degree of freedom (SDOF) system using an impedance function. The methodology is then extended to a stochastic finite element framework in order to analyze boundary-valued problems of more complex geometry and distribution of material properties. The perturbation method is a mean-based, second-moment analysis for the second-order accurate expected value, and first-order accurate cross-covariance function. For the dynamic analysis, viscoelastic response of the pavement is obtained by using the periodic-load analysis approach and Fourier synthesis. Based on the results of the simulations, it is demonstrated that, the sensitivity of surface deflections is significantly higher to the subgrade properties than those of the surface and base layers, both in a static and a dynamic analysis. Consequently, it is concluded that, the low dominant frequency of the falling weight deflectometer (FWD) load limits the capability of this test in characterizing surface layer properties. Using the concept of coefficient matrix, it is illustrated that, the low sensitivity of deflections to surface layer properties can be interpreted as a high level of uncertainty in the estimated pavement moduli in a backcalculation exercise. It is indicated that uncertainties in backcalculated parameters often result in an unacceptable pavement performance prediction. Moreover, the physical behavior of the layers are identified by finding the contribution of each layer to the total deflection of the system using the notation of contribution ratio.

abstract: Doctor of Philosophy (PhD)


title: Crazies in the Community: An Ethnographic Study of Ex-psychiatric Clients in Canadian Society--Stigma, Management Strategies, and Identity Transformation

contributor:
Haas, Jack
Sociology

subject: Sociology Sociology

abstract:
This dissertation deals with the social world(s) of former psychiatric patients in Canadian society. Adopting a symbolic interactionist perspective, specifically a labelling approach, this study, in an effort to fill a neglect in the literature, seeks to discover what the everyday world(s) of Canadian ex-mental patients are really like. Specifically, this research focusses on stigma as it applies to long-term chronic and short-term non-chronic ex-psychiatric patients, the manner by which such persons discover that they possess a stigmatizable attribute, the strategems ex-patients develop in order to mitigate the stigma potential of mental illness, and the implications of adopting such strategles for identity transformation.

Using an exploratory, qualitative approach, data were collected through participant observation and informal and semi-formal interviewing on a stratified, disproportionate, random sample of two hundred and eighty-five former psychiatric patients living in Canadian communities.

The data indicate that ex-patients categorize "mental illness" as a stigmatizable attribute through: (a) societal reaction, official labelling and processing, (b) through negative interactions with "normals," and through self-labelling. The findings indicate that ex-patients deal with the stigma potential of mental illness in a variety of ways having profound implications for identity transformation.

The long-term chronics, who not only conceive of their deviant identities as "permanent fixtures," but receive no support from others in transforming their identities, and anticipate stigmatizing responses from normals, employ the following strategies of stigma management: institutional retreatism, societal retreatism, dissociation, passing, capitulation, and subcultural participation--strategies having negative implications for identity transformation. The short-term ex-patients, who conceive of their deviant identities as "temporary fixtures," receive support from others in transforming their identities, adopt the following strategies of stigma management: selective concealment, therapeutic telling, preventive telling, normalization and political activism--strategems having positive implications for identity transformation.

In this research, it is demonstrated that actors are not passive entities, but are active in dealing with the stigma accompanying their deviant labels and identities by eliciting preferred societal reactions through their own behaviour, through the images that they project, and in attempting to transform their deviant conceptions of self. The implications of this study for labelling theory, the sociology of mental illness and for the topic of deinstitutionalization are considered.

abstract: Doctor of Philosophy (PhD)


title: Eliashberg Theory and the High Tc Oxides

contributor:
Carbotte, J.P.
Physics

subject:
Materials Chemistry
Materials Chemistry

abstract:
The Eliashberg theory of superconductivity has been very successful in accounting for properties of conventional materials. The price of this success has been a lack of understanding of exactly what features of the input parameters affect the superconducting properties in significant ways. The first part of this thesis is concerned with the identification of an important parameter in the study of thermodynamic, critical magnetic field, and electromagnetic properties of a superconductor. The Bardeen-Cooper-Schreiffer (DCS) theory of superconductivity produces laws of corresponding states, i.e., various properties are predicted to have universal values. We have studied the deviations from the BCS theory due to retardation effects, which are embodied in Eliashberg theory. These deviations, or corrections to BCS, can be well understood and characterized by a single simple parameter, to be defined later. Attention has been focused on reproducing numerical (theoretical) results, since for the most conventional superconducting materials, experiment agrees with theory at the 10% level.

The second half of the thesis has been largely motivated by the recent discoveries of the high-Tc oxide materials. We have applied Eliashberg theory almost entirely in the inverse manner. That is, with little knowledge of the microscopic parameters for these new materials, we have investigated the relationships between various macroscopically observable properties, based on model spectra. The model spectra have been of three general types, the conventional category, spectra based on a combined phonon-exciton mechanism, and thirdly those based on relatively low frequency exchange bosons. We have called this latter category the very strong coupling regime. It was hoped that measured properties could uniquely specify the type of spectrum responsible for the superconductivity in the high-Tc oxides. At this point in time this goal has not really been achieved. Too many uncertainties exist in the experimental properties, a situation which has been aggravated by a lack of single crystal data. Moreover, various kinds of measurements on the same property often give very different results. At the same time the theory needs to be improved upon. For example, anistrophy ought to be incorporated into our results, since the single crystals are displaying large anisotropies. Nonetheless, some interesting signatures for the various spectral regimes have been obtained, and these are presented in the latter half of the thesis.

abstract: Doctor of Philosophy (PhD)


title: BIOMAGNETISM: Stimulating and Recording Muscle Activity

contributor:
Pengelly, L.D.
Electrical and Computer Engineering

abstract: Biomagnetism is a two-sided discipline encompassing the magnetic stimulation of excitable tissue and the recording of magnetic fields generated by the action currents in those tissues. The present work explores new avenues in developing potential research and clinical tools for magnetically stimulating and recording muscle activity. This dissertation is presented within a cohesive experimental framework of stimulation, recording and processing. We sought to improve the magnetic stimulation of mammalian nerve, with a view towards niche applications where a minimally invasive procedure may be justified. Increased stimulus repetition rates and excellent spatial focus were achieved using small implantable "magnodes" in dog and rat hindlimbs, respectively. Generally, a three-fold increase in stimulus response was obtained, thus enabling a greater sustained stimulus rate at a given power level. An insensitivity to coil positioning was also observed in the rat. We believe two distinct mechanisms are responsible for the observed improvements in response. A toroidal coil magnetometer was developed, intended as a non-invasive tool for rapidly assessing overall activity in intact muscle. Design of the complete recording system included a low noice amplifier and a novel low frequncy magnetic shield composed of amorphous alloy. Employing non-physiological test sources, the unshielded system could resolve a multipole configuration as an equivalent dipole source. Unfortunately, the shielded could not be completed and the magnetometer's sensitivity remains inadequate for physiological work at this time. A signal processing method was developed for the purpose of filtering individual toroid recordings, and hence preclude the need for multiple stimuli. Due to the shielding problems the method was applied to data from another magnetometer. The filtering strategy offers the speed of fixed filtering with the quality of signal estimates typically found with adaptive techniques. This research has demonstrated the efficient stimulation of mammalian nerve using magnetic fields; the detection of magnetic fields from multipole current sources using non-superconducting technology; the design of lightweight and robust low frequency magnetic shields; and the efficient filtering of individual muscle response records. Continuation of the present work requires the design of a high speed magnetic stimulator and the completion of the magnetic shield.

abstract: Doctor of Philosophy (PhD)