title: Structural and Functional Changes in the Central Nervous System Following Cancer Therapy

contributor:
Noseworthy, Michael D.
Medical Physics

subject: patient quality of life

subject: central nervous system

subject: temperature sensitivity

subject: functional MRI

subject: diffusion tension imaging

subject: side effects

abstract: Chemotherapy Induced Peripheral Neuropathy (CIPN) is known to impact negatively on patients' quality of life. It has been reported that these patients tend to have sensitivity thresholds to stimuli, such as pain and temperature, that are different from those of normal subjects. The effect of chemotherapeutic agents on the central nervous system (CNS) has been observed; however, most of the mechanisms involved are not exactly understood. A quantitative investigation into the temperature sensitivity changes in the spinal cords and brains of chemotherapy patients would provide important information in understanding the side effects of this treatment modality. In the first part of the project, the temperature perceptional changes in terms of brain activation patterns of the chemotherapy patients with CIPN are studied using brain function MRI. In the second part of the project, the structural changes of the brain and spinal cord of chemotherapy patients with CIPN are studied using diffusion tensor imaging (DTI). High b-value (b = 1500 s/mm2) and low b-value (b=650 s/mm2) settings will be use during the spinal cord DTI scans. Due to the sample size limitation, no comparison between healthy volunteers and CIPN patients can be done based on the existing temperature fMRI data. However, the developed temperature fMRI protocol shows good reliability in detecting temperature response. Based on the spinal cord DTI result using b = 1500 s/mm2, decrease in FA value has been observed. The corresponding FA values of CIPN patient and healthy volunteers are 0.28±0.10 and 0.41±0.02 , respectively. (t-test = 2.63 >2.447, p=0.05 level of significant) However, no significant difference is observed in other diffusion parameters. This results also suggests that application of high b-value setting is more suitable as it is better at detecting diffusion at microstructure.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: pQCT Assessment at the Radius And Tibia: The Effects of Menopause and Breast Cancer Therapy on Trabecular and Cortical Bone

contributor:
Webber, C.
Medical Sciences

subject: cortical, trabecular, bone density, bone geometry, postmenopausal women, breast carcinoma, breast cancer, Aromatase Inhibitor, Anastrozole, pQCT, tibia, osteoporosis, cohort, TOT_DEN, TOT_CNT, CRT_DEN, CRT_CNT, deficiencies, bone quality

abstract: This thesis focuses on an examination of cortical and trabecular bone density and geometry at the radius and tibia in postmenopausal women, primarily women with history of breast carcinoma, while also assessing musculoskeletal changes in postmenopausal breast cancer patients after treatment with the Aromatase Inhibitor, Anastrozole. The first sub-study is an investigation of the reproducibility of the pQCT measurement parameters at the radius and tibia in healthy pre-and postmenopausal women. Results indicated that the reproducibility was good at the radius and even better at the tibia for all parameters measured. The second study is an appraisal of the level of osteoporosis knowledge in a cohort of postmenopausal women. The participants were assessed via the Facts on Osteoporosis Quiz, a well validated questionnaire, and the data revealed significantly lower test scores among the breast cancer subjects in comparison with healthy postmenopausal women. In the remaining group of studies, pQCT technology was utilized to describe trabecular and cortical bone at the radius and tibia in postmenopausal women and women with a history of breast carcinoma whom had been prescribed Anastrozole. The following measurement sites were significantly lower in the breast cancer subjects: TOT_DEN and TOT_CNT at the 4% radius; CRT_DEN, TOT_CNT, and CRT_CNT at the 20% radius; TOT_DEN at the 4% tibia; and CRT_DEN at the 38% tibia. With respect to time on Anastrozole, TOT_CNT at the 4% radius (r=-0.36); TOT_CNT (r=-0.33), CRT_CNT (r=-0.34) and CRT_DEN (r=-0.44) at the 20% radius; and CRT_DEN (r=-0.39) and CRT_CNT (r=-0.27) at the 38% tibia were significantly negatively correlated with days on Anastrozole. Furthermore, after two years of Anastrozole treatment in a small cohort of breast cancer subjects, there was a significant decrease in CRT_DEN (p=0.025) at the 20% diaphyseal radius and also at the 38% diaphyseal tibia (p=0.051). Together, the sub-studies that comprise this thesis demonstrate that there are noteworthy deficiencies in osteoporosis knowledge among postmenopausal women, particularly those with a history of breast carcinoma, and yet, these are the same women that have an increased need to understand the preventative and treatment options regarding this disease as they demonstrate reduced bone density at all measurement sites. It also appears that time on Anastrozole primarily affects cortical bone density in these women. In summary, this thesis provides novel details regarding cortical bone in breast cancer subjects and emphasizes the need for a normative database of bone quality parameters at different skeletal sites in order to gain a better understanding of the utility of each skeletal site with regard to fracture risk prediction.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Design of Minimal Ion Channels

contributor:
Yang, Daniel S. C.
Biochemistry and Biomedical Sciences

subject: ion, modular property, ion channels, crystal structures, chimeric channel, pore-forming, conductivity, selectivity, drug-binding, C-terminal cytoplasmic, KcsA, tetramerization, thermostbility, pore-forming domains, thermostability, tetrameric, coiled coils, potassium channels

abstract:
 We developed some universal platforms to overexpress the minimal functional entities of ion channels. The modular property of ion channels have been demonstrated from many aspects, such as crystal structures, chimeric channel experiments and discovery of similar modules in distantly related protein families. Thus it should be feasible to express each module independent of other channel modules. The pore-forming module of ion channels has multiple important properties as selectivity, conductivity and drug-binding. If it can be overexpressed, it will provide valuable information about channel selectivity to different ions and structural bases for drug binding as well as important application in drug screening and rational drug design.

 To test this, we first used the model channel KcsA to identify the minimal requirements for a pore-forming domain to functionally exist independently. Chapter 2 of this thesis explains in detail how the wild type C-terminal cytoplasmic domain of KcsA functions. We found that this domain has dual function as pH-sensor and tetramerization domain, and it is essential for the expression of the pore-forming domain of KcsA. Once we knew the physiological role of the cytoplasmic domain, the scenario was set to answer the question of how to make it better for the application of structural and functional studies.

 In chapter 3 and chapter 4, we replaced the wild type C-terminal domain with non-native tetramerization domains. We identified the direct correlation between protein expression level and overall thermostability of pore-forming domains. The C-terminal tetramerization domains stabilize channels in a cooperative way and play a critical way in in vivo channel assembly. The selection of the linker between pore-forming domain and tetramerization domain, the splicing motif, and the handedness of C-terminal tetrameric coiled coils all affect channel expression level and stability.

 We applied our finding in KcsA to a wide range of ion channels in chapter 5, including voltage-gated potassium channels, Ca2+-gated potassium channels, inwardrectifying potassium channels, cyclic nucleotide-gated potassium channels and voltagegated sodium channels. We managed to express similar minimal structural modules from these more structurally complicated channels with the assistance of different cytoplasmic tetramerization domains. Several minimal channels expressed well and showed similar biophysical and functional property as the wild type channels.

 These studies demonstrate that the pore-forming modules of ion channels can be expressed independently while retaining the proper structure and drug-binding properties as their wild type predecessors when using our universal expression platform. The potential application in structural studies and drug-screening is promising.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Serotonergic Neurons of Drosophila melanogaster Larvae: A Study of Their Development and Function

contributor:
Campos, Ana R.
Biology

subject: Drosophila melanogaster

subject: central nervous system development and function

subject: interactions of serotonin-producing neurons

subject: larval photobehaviour

abstract:
Drosophila melanogaster is an attractive model organism for the study of numerous fundamental processes including nervous system development and function. This is due to the power of Drosophila genetics combined with the high degree of similarity between this organism and vertebrate systems, not only at the molecular level but also at the cellular and behavioural levels.
The first part of my thesis focused on trophic interactions occurring in Drosophila larval central nervous system. Specifically, it describes the interaction of serotonin (5HT)-producing neurons with other three groups of neurons: the larval photoreceptors expressing Rhodopsin 5 (Rh5), the photoreceptor subset expressing Rhodopsin 6 (Rh6), and the larval circadian pacemakers (LNv). I found that both Rh5-and Rh6-expressing fibers contact a 5-HT arborization in the larval optic neuropil, where the 5-HT processes also overlaps with the dendrites of the LNv. The results of my experiments also indicate that the Rh6-expressing terminus is the neural process providing the signal required for the outgrowth of the serotonergic arborization. Furthermore, proper branching of this arborization requires normal Rae function. These findings further support the importance of extrinsic and intrinsic signalling for the assembly ofthe nervous system.
The remainder of my studies attempted to investigate candidate neurons modulating Drosophila larval photobehaviour. Using the larval response to light as a behavioural paradigm and neuronal silencing experiments, my results demonstrate that 5HT neurons located in the brain regulate the larval photoresponse during development. In addition, my findings suggest that this modulation occurs at a central level and that is mediated by 5-HT1A(Dro) receptors. These observations provide new insights into the functions of serotonergic neurons in Drosophila as well as how neuromodulators shape neuronal circuit function and ultimately behaviour.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Study of Luminescent Si-Based Materials Through X-Ray Spectroscopies

contributor:
Mascher, P.
Engineering Physics

subject: light, luminescent, silicon, spectroscopies, atoms, absorption

abstract:
 Light emitting silicon nanostructures are of significant interest for photonics due
to their potential to act as the source material for a monolithically integrated Si-based
light source. This thesis reports on the experimental characterization of such luminescent
structures formed in silicon nitride, oxynitride, and rare earth doped silicon oxide thin
films. Changes in the electronic structure of the materials have been analyzed using soft
X-ray spectroscopy by probing the constituent elements at their absorption edges. The
observed near edge structure at these edges is related to the local atomic bonding
environment of the probed atoms. Specifically, changes in the near edge structure at the
Si K and L3,2 absorption edges can be related to the coordination of silicon atoms within
the films.

 In the silicon nitrides the Si-clustering process has been observed to onset at different anneal temperatures, dependant on film composition. In films that have a small amount of excess Si higher anneal temperatures are required before a significant Si-Si
bonding signal is observed. In samples with high concentrations of excess Si this
clustering process is observed to occur at temperatures as low as 700 °C. In silicon
oxynitride samples only a small fraction of the excess Si forms into clusters within the
films. Rather, in these samples the formation of distinct silicon oxide and silicon nitride
phases is observed, with strong absorption related to the formation of the oxide phase
being observed after annealing at high temperatures (T ≥ 1000 °C). The nanoclusters were determined to be amorphous in nature, rather than nanocrystalline, through the use
of high-resolution, energy filtered, and scanning transmission electron microscopy. This
behavior was seen even for samples with high excess Si concentrations and annealed at
high temperatures. This contrasts with the behavior of silicon-rich silicon oxide thin films
were nanocrystals are clearly observed after similar treatments, indicative of the influence
of the nitride host matrix on the cluster formation process.

 Changes in the electronic structure at these edges have been correlated with changes in the bonding structure within the films, as analyzed through Fourier transform infrared spectroscopy, and with the photoluminescent behavior of the films.

 X-ray excited optical luminescence (XEOL) has been used for the study of rare earth doped silicon oxides, allowing for site specific excitation of the films in order to analyze the origin of luminescence in the films. In O-rich samples the luminescence of the films has been observed to be strongly excited at O-related absorption edges while in Si-rich samples XEOL is observed at Si-Si bonding absorption energies. The results indicate the presence of different sensitization pathways towards luminescence in the films, including the formation of oxide or silicate phases.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Globalization, Cotton and Poverty South of the Sahara

contributor:
Coleman, William D.
Political Science

subject: cotton, poverty, Afrixa, Sahara, policy, donors, globalization

abstract:
 This study details the historic relationships between cotton and poverty in Africa south of the Sahara. It assesses the impacts that nongovernmental policy advocacy and corporate social responsibility have had on the factors that impoverish Africa's cotton producers. The new nongovernmental and corporate interest in the conditions of life on Africa's cotton farms has increased the likelihood that rising numbers of families that depend on cotton will endure fewer impoverishing relationships. Even so, there is little to suggest that the linkages between cotton and poverty will be eradicated in the present era of globalization should present trends hold. Nongovernmental advocates have contributed to narrowing the debate on Africa's cotton problem at the World Trade Organization even as they have successfully encouraged multilateral, bilateral and nongovernmental donors to scale up their efforts in this issue area. Similarly, many corporate social responsibility initiatives have targeted only certain aspects of poverty and have embraced light-touch approaches to 'doing' responsibility. That said, evidence from Tanzania indicates that a certified organic cotton production operation there has established a parallel governance structure that has effectively reduced poverty and empowered agriculturalists.

 The international political economy approach developed below adds value to the available literature on African cotton. It treats poverty as a multidimensional phenomenon and embraces a non-economistic treatment of globalization to produce a broader understanding ofpoverty and the factors that are maintaining or alleviating aspects of it in the contemporary world economy. The way of knowing about cotton and poverty presented here is inductive and also historicist, and relies upon field research and case studies. This contribution adds a comprehensive global level of analysis to the literature on Africa's cotton problem, and also prescribes possible policy options that could be relevant in Tanzania and elsewhere.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Low Temperature Study of the N-Channel MOS FET

contributor:
Chisholm, S. H.
Electrical Engineering

subject:
silicon n-channel MOS FETs
interface states
temperature dependence
pinch-off voltage
1/f noise

abstract: Scope and contents: The static and dynamic electrical characteristics of silicon n-channel MOS FETs are studied down to cryogenic temperatures. Particular emphasis is directed towards the effect of interface states on the temperature dependence of both the pinch-off voltage and 1/f noise.

abstract: No abstract included.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Some Reactions at the C-7 Position of Norbornenes

contributor:
Warkentin, J.
Chemistry

subject: organolithium, reactions, C-7, Norbornenes,

abstract:
 The addition reaction between bicyclo[2.2.1]hept-2-en-7-one and several organolithium reagents was investigated. Saturated alkyllithium reagents, like most Grignard reagents, were shown to add preferentially to the syn-face of the ketone, while unsaturated alkyllithium reagents add preferentially to the anti-face. These results have been rationalized in terms of bimolecular attack by the former reagents and unimolecular attack by the latter reagents.

 The 7-t-butylbicyclo[2.2.1]hept-2-en-7-cation was shown to rearrange in mildly acidic media to a cation which lost a proton to yield syn-7-methyl-7-(2'-propenyl)bicyclo[2.2.1] hept-2-ene. The formation of this product can be explained by a Wagner-Meerwein migration which proceeds with retention of configuration about the C-7 cation centre.

 A series of 7-R-bicyclo[2.2.1]hept-2-en-7-radicals were allowed to abstract hydrogen from tri-n-butylstannane. When R = CH3, i-C3H7, n-C4H9, neopentyl, no stereochemical preference for syn- or anti- abstraction was observed. When R = t-C4H9, a large preference was shown for abstraction to occur on the anti-face, while when R = C6H5, syn-abstraction predominated. These observations, in the light of observations of abstraction by the bicyclo[2.2.1]hept-2-en-7-radical, are consistent with homoallylic participation of the double bond at the radical centre of the latter species.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Hydrological and Geomorphological Observations on a High Latitude Drainage Basin: "Jason's Creek", Devon Island, N.W.T.

contributor:
McCann, S.B.
Geography

subject: "Jason's Creek", hydrological, high latitude, drainage, basin, layer, channel

abstract:
 "Jason's Creek" is a stream draining 2.2 km^2 of arctic limestone terrain. Its annual regime consists of a ten-month period in which it is frozen to its bed, a short spring flood which occurs shortly after tenperatures cross the freezing-point in late June, and a period of about two months during which discharge is relatively low and fluctuates diurnally in response to inputs of radiative and heat energy to the snowpack. In 1970, the spring flood occupied the first two weeks of July and effected the discharge of some nine-tenths of total annual runoff. Tne low flow period was punctuated by rainstorms which generated sharply-defined floods: basin response was rapid and efficient, for storm runoff is facilitated over the unvegetated ground and through the shallow active layer above the permafrost table. Covariance and spectral analyses suggest a basin lag time of five hours, both for low discharges of snowmelt water and flood discharge of rainwater. It appears, from the spectra of the time series, that radiation is a better index of snowmelt discharge than is temperature.

 Most of the annual removal of sediment from the basin takes place during the spring flood, when the stream is turbid and movement of channel bed material is vigorous, In the longer period after the flood the main component of stream load is the solute load. The concentration of dissolved material varies inversely while suspended sediment concentration varies directly with discharge. Solute concentrations are lower than those commonly found in limestone streams at lower latitudes, suggesting that in "Jason's Creek" the increased solubility of CO2 at low temperatures is more than counteracted by a decrease in the rate of solution of CaCO3. There are also indications that the concentration of CO2 in snowmelt water 2 may be smaller, in absolute terms, than in rainwater.

 The role of water is crucial in many processes acting on slopes and delivering detritus to stream channels; rills, for example, remove ions in solution and fine particles in suspension, notably from the base of talus slopes, and lubrication of the active layer after rainstorms generates bowl-slide and mudflow activity.

abstract: Thesis

abstract: Master of Science (MSc)


title: Flexor tendon motion and shear in the carpal tunnel: implications for work

contributor:
Keir, Peter J.
Kinesiology

subject:
Occupational biomechanics
Carpal tunnel syndrome
Friction
Tendon travel
Subsynovial connective tissue

abstract: Carpal tunnel syndrome is characterized by non-inflammatory fibrosis of the subsynovial connective tissue next to the tendons in the carpal tunnel, suggesting a shear injury owing to repetitive wrist and finger motion at work.  I tested the effects of several well-established biomechanical predictors of injury on tendon and subsynovial connective tissue motion and shear in the carpal tunnel. These included non-neutral finger and wrist posture, speed of work, and forceful exertion.  A cadaveric paradigm was used to directly measure tendon gliding characteristics, which showed that concurrent exposure to multiple biomechanical risk factors disproportionately increased tendon frictional work (Chapter 2).  Given that tendon shear cannot be directly measured in vivo, colour flow ultrasound was used to assess relative motion between tendon and subsynovial connective tissue as a metric of shear potential (Chapter 3 − 5).  Healthy participants completed middle finger movements while colour flow ultrasound imaged carpal tunnel structures and optical motion capture recorded finger joint kinematics.  From the data, I developed regression equations to predict both tendon and subsynovial connective tissue displacements as a function of finger joint angles, which can be used as an ergonomic method to calculate the relative displacement (Chapter 3).  Furthermore, relative motion between tendon and subsynovial connective tissue increased with wrist flexion angle, suggesting a greater susceptibility to shear injury during repetitive work when the wrist is flexed (Chapter 4).  Using colour flow imaging, electrogoniometry, and fine-wire EMG, relative displacement was found to increase with tendon velocity and force (Chapter 5).  Relative displacements in Chapters 3 to 5 were combined into a prediction model, and further compared to a tendon friction model derived from Chapter 2.  The relative displacement model showed an additive relationship with combined physical exposures, including finger and wrist position, tendon velocity, and force (Chapter 6).  The relative displacement model was more responsive to lower physical exposures whereas the friction model produced greater overall changes (with higher exposures).  While both models infer a greater risk of shear injury due to repetitive and forceful wrist/finger movement, future studies will aim to set protective guidelines based on tendon motion and shear during hand-intensive work.  Overall, this thesis showed that tendon friction and relative motion between tendon and subsynovial connective tissue both increased in response to well-established biomechanical risk factors.  We propose the current models for use in ergonomics, representing a move towards mechanistic-based injury risk assessment of the wrist and hand.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Studies of Promoted And Supported Catalysts With An Electron Probe Microanalyzer

title: Electron Probe Studies of Promoted and Supported Catalysts

contributor:
Anderson, R.B.
Chemical Engineering

subject: Electron probe microanalyzer, catalysts, iron ammonia, synthesis, promoters, reduction process, impurity, silica, chromium, copper impregnated

abstract:
 Promoted and supported catalysts were studied with
an electron probe microanalyzer. Investigations we re made on promoted fused iron ammonia synthesis catalysts regardirlg the general morphology of the catalysts, the distribution of promoters, and the reduction and poisoning processes . The effect of the promoters on the reduction process , the effect of the impurity silica on the promoter distributions and the nature of the poisoning are discussed. Supported catalysts were prepared by impregnating porous y-alumina spheres with solutions of chromium and/or copper compounds. Concentration profiles for chromium and/or copper , i.e., concentration as a function of distance from the center, were determined on sectioned spheres. Different distributions of these elements on the alumina support were obtained by varying the chemical used, the concentration and the amount of the solution impregnated. Explanations are given for the physical and chemical processes involved during the impregnation . The amount of chromium or copper impregnated is compared with the amount present in each particle.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Quadrupole Interactions of Ta181 in a Polycrystalline Hafnium Dioxide Environment

contributor:
Prestwich, W.V.
Physics

subject: quadrupole, interactions, polycrystalline, hafnium, nuclear,

abstract: </p> A study of the quadrupole interactions of Ta181 in a polycrystalline hafnium dioxide environment is described in this work. A general introduction to the concepts of angular correlations in nuclear physics is given in Chapter 1 followed by the main outlines of the theory of quadrupole interactions. Instrumental effects involved in the measurement of such an interaction and the analysis of data using Fourier transform methods are discussed. Descriptions of the structure of HfO2 , the factors involved in attaining short time resolutions in timing and the experimental system and methods used in the study are given. The final two chapters contain the results and conclusions with comparison with results from other works.</p>

abstract: Thesis

abstract: Master of Science (MSc)


title: The Land Use of Eramosa Township

contributor:
Bik, M.J.J.
Geography

subject: Land use, Eramosa Township, control, physical, historical, landscape, pattern, rural, urban, population, British ancestry, villages, guleph, Brantford, Hamilton, Kitchener, Nichol Townships, Puslinch, Garafraxa, Erin, Nassagaweya, Halton County

abstract:
No Abstract Provided
Thesis
Bachelor of Arts (BA)


title: The Origin of Certain Granitic Rocks Occurring In Glamorgan Township, Southeastern Ontario

title: Origin of Certain Granitic Rocks

contributor:
Shaw, Denis M.
Geochemistry

subject: Glamorgan township, Ontario, Canada, rocks, Precambrian, Grenville, migmatite, paragneiss, granite, gneiss, Glamorgan gneiss series, geochemical, melting, trondhjemitic melt, granitic, metavolcanic, metasedimentary, diorite, alkaline gabbro, low pressure, kilobars, geothermal gradients, terrains, sodium, potassic

abstract:
 Glamorgan township in southeastern Ontario, is underlain by Precambrian rocks of the Grenville province. Prominent amongst these are migmatite, paragneiss, and granite gneiss, VJhich collectively form a series of rocks (the Glamorgan gneiss aeries).

 Field work revealed that this series is completely gradational from a geological aspect, and that the geological gradation is complemented by a geochemical gradation.

 An explanation of these gradational relationships constitutes the main contribution of this study. The conclusions reached are that partial melting of paragneiss produced migmatite and a trondhjemitic melt, which later produced granitic (in the strict sense) derivatives.

 In developing the main conclusions, a number of subsidiary problems are discussed, chief of which are the possible metavolcanic or metasedimentary o'rigin of the paragneiss and the possible origin of so-called diorite as a differentiate of an alkaline gabbro. Metamorphism was concluded to be of Miyashiro's low pressure intermediate type.

 By the use of experimentally determined reactions and stability fields a metamorphic grid was devised, which led to the following upper limits of metamorphic conditions: 550 to 650°C and 3 to 6.5 kilobars total pre5sure. These estimates in turn lead to the following limiting geothermal gradients: 25 to 55°C per kilometre.

 The Glamorgan occurrence was found to share three characteristics with many other Precambrian terrains : 1. migmatisation and emplacement of granite accompanied high grade metamorphism; 2. an early sodium-rich granite was followed by a more potassic one; and 3. the more sodic granite is associated with a small amount of basic igneous rock. These three generalisations were used to formulate a possible model for deep crustal petrogenesis.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Preparation and Evaluation of Molecular Imaging Probes Targeting the Urokinase Plasminogen Activator System

contributor:
Valliant, John
Chemical Biology

subject:
upa
cancer
molecular imaging
radiochemistry

abstract:
The aim of this thesis was to develop a molecular imaging probe for the urokinase plasminogen activator (uPA) system, which has been shown to play a critical role in cancer metastasis, tumour aggressiveness and likelihood of progression. Two classes of small molecule inhibitors carrying isotopes of iodine were synthesized and evaluated using in vitro assays and in vivo studies. Lead compounds showed high affinity for the target with Ki values in the low nanomolar range (1b = 1.4 nM, 1e = 6.1 nM, 1g = 2.6 nM and 2a = 2.1 nM). Biodistribution studies of the reversible compounds (1b, 1e, 1g) showed rapid clearance, accumulation in the gall bladder and intestines and little to no tumour uptake (<1 %ID/g). The irreversible inhibitor (2a) showed specificity for the target through SDS-PAGE and biodistribution studies. Analysis of the biodistribution pattern showed retention in the tumour over time reaching a maximum at 24 h post-injection of 1.95 %ID/g with tumour-to-blood ratio being 0.65 at 24 h, 1.13 at 48 h and 1.09 at 96 h post-injection.
          A parallel strategy reported involved targeting the uPA receptor (uPAR) through the use of antibodies and bioorthogonal chemisty based on radiolabeled tetrazines and transcyclooctene (TCO) functionalized biomolecules. A new tetrazine synthon was developed that can be readily labeled with both 99mTc and 18F where the products were produced in 75 and 31 % radiochemical yields. Stability studies showed the compounds are suitable for use in vivo. Biodistribution studies were carried out in CD1 mice and results showed that both probes had sufficient distribution patterns to warrant use in pre-targeting strategies. Their reactivity with TCO, including functionalized derivatives such as TCO-anti-uPAR, was also demonstrated creating the means to develop PET and SPECT probes for imaging the urokinase system using a single prosthetic group.

abstract: Thesis

abstract: Master of Science (MSc)


title: Optimization Of The Oxidation Of Sulphur Dioxide In An Existing Multi-Bed Adiabatic Reactor

contributor:
Crowe, C. M.
Chemical Engineering

subject: sulphur dioxide, sulphuric acid,  temperatures, catalyst, air, variables, nonlinear differential equations, Runge-Kutta third-order

abstract:
 The sulphur dioxide converter of the contact sulphuric acid plant ~f the Hamilton Works of Canadian Industries Ltd., is optimized using the so2 conversion as the objective function to be maximized. The simulation model used is fitted to the plant data. The number of beds, the inlet temperatures, the catalyst bed depths and the air addition are the variables considered in this work. The effect due to the imposition of a constraint on the system is also examined.

 Four integration techniques are studied to solve the set of nonlinear ordinary differential equations that simulates the transformation in a bed. The Runge-Kutta third-order is found to be the most efficient.

 Four optimization techniques, namely, dynamic programming, gradient search, direct search of Hooke and Jeeves and discrete maximum principle, are used. Their applicability and efficiency are compared.

 A very flat response (conversion) surface is found in the neighbourhood of the optimum.

 The optimal operating conditions are compared with the simulation of the C.I.L. operation. The reachability of these optimal conditions in the plant is also considered.

abstract: Thesis

abstract: Master of Engineering (ME)


title: The Change in the Response of Ge(Li) Gamma Radiation Due to Damage Caused by High Energy Neutrons

contributor:
Kennett, T.J.
Physics

subject: Ge(Li), gamma ray, damage, energy, neutrons, radiation

abstract:
 This thesis deals with the changes, in the response of a Ge(Li) gamma ray detector, arising from damage caused by its exposure to high energy neutrons. The phenomenon of charge trapping is considered and included in a model explaining the collection of electron-hole pairs in a Ge(Li) detector. From this model a response function for the output of the detector is obtained and then applied to a description of the changes in FWHM of pulse height spectra peaks with energy and neutron irradiation.

 Described are experiments in which three detectors were exposed to fast neutrons and their changing response was related to the response function. Finally the number of damage centres produced by the neutrons is discussed.

abstract: Thesis

abstract: Master of Science (MSc)


title: Mass Spectrometry of Organic Compounds Part I. Oxygenated Quinolines and Furoquinoline Alkaloids Part II. Lobinaline and its Hofmann Degradation Products

contributor:
MacLean, David B.
Chemistry

subject: spectra, furoquinoline, alkaloids, lobinaline, oxygenated

abstract:
</p> Part I
The mass spectra of the seven isomeric monomethoxyquinolines,
the seven monohydroxyquinolines, the two N-methylquinolones and six furoquinoline alkaloids have been recorded. Fragmentation mechanisms are proposed to account for the major peaks in all the spectra. Use has been made of intense metastable peaks found in most of the spectra to aid the interpretation of the fragmentation routes. In addition, deuterium and carbon-13 labelling have been employed in analyzing the fragmentation routes of the methoxyquinolines. </p> <p> Part II
The Hofmann degradation of lobinaline is described. Examination
of lobinaline, its derivatives and its Hofmann degradation
products by mass spectrometry and other physical and chemical techniques has allowed a structure to be assigned to the alkaloid.</p>

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Geochemistry of Pd, Os, Ir and Au in the Mount Albert Ultramafic Pluton, Quebec

contributor:
Crocket, James H.
Geology

subject:
neuron activation analysis
Mount Albert ultramafic pluton
precious metal content of rocks
dunite
peridotite
serpentinized
unserpentinized
chrome spinel
clinopyroxenite
chromite

abstract:
A neutron activation analysis procedure for the simultaneous determination of Au, Pd and Ir, and separate determination of Os is described and applied to the determination of these metals in the Mount Albert ultramafic pluton, Quebec. The Mount Albert is an alpine-type ultramafic body whose petrography, geology and geochemistry has been discussed in some detail by MacGregor (1962, 1964). It consists mainly of serpentinized dunite and peridotite. However, it is distinguished by the presence of an eastern lobe which is essentially unserpentinized. In addition to ferromagnesians, two varieties of spinel including disseminated accessory chrome spinel and massive, discordant chromite veins or schlieren are important mineralogical constituents. Twenty samples were analyzed including 5 fresh dunites and peridotites, 8 serpentinized equivalents, 4 disseminated chrome spinels, 1 clinopyroxenite, and 2 massive chromite. The concentrations (in p. p. b.) of average fresh ultramafics and their serpentinized equivalents are:--------------------------------------
---------------------Pd----Os----Ir----Au-------------------------------------------                                               Fresh rocks------------7.7----7.2--2.5--0.99-------------------------------------------                                    Serpentinized rocks---10----6.6--2.2---2.4--------------------------------------------
     The piuton was intruded as a nearly solid mass of olivine and some orthopyroxene with about 15 weight per cent melt. A small concentration of the precious metals, a factor of 2 to 3, in the melt relative to crystalline phases appears to have occurred. The disseminated chrome spinel and massive chromite appear to concentrate the precious metals. In particular, Os and Ir content of the massive chromite is approximately 10 times that of fresh or serpentinized whole rocks.
     There is little change in average precious metal content with serpentinization. Pd shows a slight increase, and Ir and Os slight decreases in concentration with degree of serpentinization. Only Au appears significant to be enriched in serpentinized rocks where a twofold increase occurs. The variation in precious metal content of all four metals increase when the rocks are serpentinized: When normalized to chondrite meteorites, the precious metal data give fractionation trends similar to that of average chondrite. These trends are compatible with a model in which alpine ultramafics are regarded as residua from the partial melting of parental material of approximately chondritic composition.

abstract: Thesis

abstract: Master of Science (MSc)


title: THE DESIGN OF A NOVEL LYAPUNOV-BASED OFFSET-FREE MODEL PREDICTIVE CONTROLLER

contributor:
Mhaskar, Prashant
Chemical Engineering

subject:
Process Control
Model Predictive Controller (MPC)
Moving Horizon Estimation (MHE)
Offset-free

abstract:
This thesis considers the problem of control of nonlinear systems subject to limited availability
of measurements and uncertainty in model parameters. To address this problem, first a
linear offset free MPC is designed. Subsequently, a Lyapunov-based offset free MPC design
is presented to handle structured uncertainty subject to constant disturbances. The controller's ability to handle unstructured uncertainty and measurement noise is demonstrated through simulation examples. Next, the problem of handling lack of state measurements as well as uncertainty is considered. To achieve simultaneous state and disturbance parameter estimation, a Lyapunov-based model predictive controller (MPC) is integrated with a moving horizon based mechanism, to achieve (where possible) offset elimination in the unmeasured states as well. A chemical reaction process example is presented to illustrate the key points. Finally its efficacy is demonstrated through a polymerization process example.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Universal Algebra Complexes: Extensions and Integral Elements

contributor:
Banaschewski, Bernhard
Mathematics

subject: universal algebra complex over an algebra

subject: unitary algebra homomorphism

subject: differential forms

subject: finiteness theorem

subject: integral differential forms

subject: E. Kähler

abstract: No abstract provided.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Scope and contents: Two topics are studied in this thesis. The first topic is concerned with the relation between the categories of complexes over two algebras when there is a unitary algebra homomorphism from one to the other. The second topic deals with differential forms. A certain finiteness theorem for the module of integral differential forms is studied.


title: Classification of Precambrian Shield Lakes Based on Factors Controlling Biological Activity

contributor:
Kramer, J.R.
Geology

subject: lentic, environment, Precambrian, shield, morphology, classified, lakes

abstract:
 During the summer of 1970 a study was initiated to define
factors controlling the biosphere in the lentic environment of
the Precambrian Shield. Data were collected from nine lakes of
varying size and depth located in a number of geological formations. Chemical, physical and biological conditions in these
lakes were investigated at two sampling periods and the lakes were classified on the basis of morphology (surface area to volume
area) and lithology (surficial and bedrock geology). Attempts
were made to determine the influence of morphology and lithology
on the chemical and biological conditions observed. Emphasis
was placed on the relationships of these factors to aspects of the
primary and secondary trophic levels in the lentic ecosystem
including primary productivity and the standing crop and diversity
of phytoplankton and zooplankton.

 The atmosphere, a third potential factor influencing lakes was investigated by means of a network of air monitoring stations (collecting both precipitation and 'dry fallout') located throughout the greater Sudbury area.

 The results of the study indicated that:
1. the lentic ecosystem in the Precambrian Shield area studied can be defined by simple chemical and physical variables.
2. the morphology of the lake basins (surface area to volume ratio) modified by lithology (primarily the presence or absence of limestone) is the major factor influencing biological activity. Lakes with a low surface area to volume ratio showed low productivity while lakes with a high surface area to volume ratio showed nigh productivity. Silica and calcium concentrations (influenced by the lithosphere) were important since relatively small changes in the concentration of these chemical species stimulated a response in the biosphere.
3. some of the lakes were affected by concentrations
of sulphates conveyed to the water by the atmosphere.
Observed effects included increases in the hydrogen ion concentration in lakes with low calcium concentrations (poorly buffered) and a depression of the diversity of both primary and secondary trophic levels.

abstract: Thesis

abstract: Master of Science (MSc)


title: Thrust-Cushion Vehicles, A Preliminary Analysis

contributor:
Newcombe, W.R.
Mechanical Engineering

subject: air-cushion, vehicles, pressure, thrust-cushion, model

abstract:
 Air-cushion vehicles (ACV) are defined as surface vehicles that utilize air pressure for partial-or total support over the operational surface. An outline of the history of the five widely known ACV concepts and an analysis of the mode of operation of each is given, with their advantages and disadvantages.

 A sixth type, called the thrust-cushion vehicle (TCV), is a promising but unknown concept which, as yet, has not received much study or recognition. A preliminary theoretical analysis for design purposes is made, and the test results of a static model and a model running on a radial tether are given to establish a research and design basis for future work.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Petrology of Some Early Tertiary Lavas of the Kettle River Region, British Columbia

contributor:
Crocket, J. H.
Geology

subject:
Tertiary lava
Kettle River area
British Columbia
petrography
minerology
petrogenesis
rocks
magma series

abstract: Information provided by previous workers shows a considerable diversification of lava types in the early Tertiary deposits of the Kettle River region of British Columbia. The aim of the present study is to establish, on the basis of mineralogical and chemical evidence, whether or not these lavas form a single magma series. A suitable spectrochemical technique was adapted for the determination of Sr, Ba, CaO, MgO, and FeO in rock samples and mineral extracts. A method based on the work of Shaw and Filby, using lanthanum as an internal standard for determination of Sr, Ba, and Ca, is extended to include the determination of MgO and FeO. Extension of the available chemical data was possible using a fused glass bead technique for refractive index determination of the lavas. In view of good correlation between refractive index and the most refractory constituents of the lavas CaO, MgO, and FeO, the refractive index serves as a good magmatic differentiation index. Examination of the refractive indices of three suites of samples, taken from widely separated points within the Kettle River region, shows that the lavas range from semi-basic to acid composition with intermediate types, andesites and trachyandesites, predominating. There is a marked paucity of basaltic rocks. The stratigraphic distribution of the lavas reveals no consistant trends toward either acid or basic compositions; neither is there any relation between stratigraphic position and lava types within the region concerned. In spite of close age and spatial association of the lavas, petrological evidence points to a three-fold division of these rocks (termed 'A', 'B' , and 'C' series). 'A' series is similar to the silica-enrichment 'calc-alkali' trend showing regular mineral and chemical progression from andesites to latite and rhyolite. 'B' series is characterized by a somewhat less well defined group of two-feldspar lavas, trachyandesites, and trachytes. An unusual undersaturated lava, termed 'analcite rhomb-porphyry' or 'shackanite' is thought to be genetically related to 'B' series but probably belongs to a poorly developed semi-basic alkali trend, 'C' series. A mechanism involving crystal fractionation of hornblende, or alternately, augite and plagioclase, is envisaged as the probable mode of origin for many of the rocks of 'A' series. On the other hand, Daly's view that the shackanite lavas were formed as a result of limestone assimilation is supported by field evidence as well as mineral and chemical data. The rocks of 'B' series, the trachyandesites and trachytes, are intermediate in composition to 'A' and 'C' series and have probably formed by process of crystal fractionation in consequence of normal cooling conditions and limestone assimilation.

abstract: Thesis

abstract: Master of Science (MSc)


title: Carrier Synchronization in a Digital Radio System

contributor:
Taylor, D.P.
Electrical Engineering

subject: carrier, duobinary, digital, radio, feedback loop,

abstract: Page 139 not included in the thesis.

abstract:
 The problem of coherent carrier recovery and the effects of
phase error on the performance of an offset quadrature-phase-shift-keying (QPSK) duobinary system have been investigated in the thesis. The system of interest is similar to RD -3 digital system that is being developed and installed as an efficient high data-rate digital radio communication system by Bell Northern Research Laboratory (BNR).

 Four carrier regeneration loop structures are investigated and analysed in the thesis. These are:
(i) estimate-aided suppressed carrier loop
(ii) decision-directed feedback loop
(iii) shifted decision-directed feedback loop
(iv) half-shifted decision-directed feedback loop
All of these loop structures employ the technique of data-aided carrier synchronization. The estimate-aided loop structure exhibits steadystate behavior similar to that of a conventional Costas loop. The remaining three loop structures differ from the estimate-aided loop in the sense that they require decisions to make on the noisy received signal. These are then fedback to the carrier recovery circuit in such a way as to create a spectral line at carrier frequency. The loop behavior in the presence of additive noise has been investigated in some detail. For each loop, analytical expressions for the phase detector characteristic (S-curve) and the steady-state phase error probability density function (pdf) are derived, and provide a means of comparing the performance of the different recovery schemes.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: The Influence of Anaerobic Conditions on Activated Sludge

contributor:
Murphy, K.L.
Civil Engineering

subject: anaerobic, storage, metabolic, oxygen

abstract:
 A study was made to determine the elimination rate of soluble organic and inorganic compounds during anaerobic storage. Using aerobic storage as a comparison, some insight could then be gained into the metabolic activities of a mixed culture.

 The rate of oxygen utilization following anaerobic storage appeared to be dependent on the level of aeration within the reactor prior to storage. There was no liberation of carbon to account for the increased oxygen uptake following storage. Although there was a slight decrease in the solids level, it was independent of the type of storage.

 The nitrate ion appeared to act as a hydrogen acceptor during anaerobic storage and, upon reaeration, the nitrate level tended to level off. There was a production of ammonia during both aerobic and anaerobic storage indicating a deamination of cellular material (loss of solids).

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: A Study in Steiner Quadruple Systems

contributor:
Rosa, A.
Mathematics

subject: theory, Steiner, quadruple, systems, automorphism, non-S-cyclic

abstract: This thesis is a contribution to the theory of Steiner quadruple systems. The first chapter provides a construction of resolvable Steiner quadruple systems that is different from the known constructions. In the second chapter, we construct Steiner quadruple systems with an automorphism that consists of a cycle of length 2 plus a cycle of full length minus 2, and investigate the number of pairwise distinct systems of this kind. In the third chapter, we also construct non-S-cyclic Steiner quadruple systems, one of which is an answer to a question raised in [11], and also investigate the number of pairwise distinct systems.

abstract: Thesis

abstract: Master of Science (MSc)


title: Structure and Reactions of Some Sulphides and Selenides of Phosphorus and Arsenic

contributor:
Gillespie, R.J.
Chemistry

subject: structural, oxidative, phosphorus, arsenic, selenium, compounds,

abstract:
 A continuation of studies of main group compounds
carried out in this laboratory has led to the investigation
of the structural and oxidative chemistry of several
compounds and mixtures of the elements phosphorus, arsenic,
sulfur and selenium. A number of questions and a lack of
data regarding known compounds of these elements lead to
an examination of the series P4-X^AsX^S3-Y^SeY, X = 0-4,
Y = 0-3. Raman spectra of several members of the series
have been recorded. The 31P and natural abundance 77Se
nmr spectra of these compounds were also recorded, including
a reinvestigation and complete assignment of the 31P nmr
spectrum of P4Se3 . Several trends in the coupling constants
and chemical shifts were noted and an empirical equation
was devised for the 31P nmr spectral assignments for
quaternary members of the series. The compound formerly
believed to be P2As2S3 was shown to be PAs3S3. The crystal structure of an occupationally disordered crystal
of stoichiometry P2As2S3 is also reported in this thesis.

 The compound As4S4 and 1:1 As:Se fused mixtures
were separately oxidized with the Lewis acids AsF5 and
SbF5 to produce the new cations As3S4+ and As3Se4+. The cations were characterized as the salts As3S4 (AsF6), As3S4 (SbF6), As3Se4 (AsF6 ) and As3Se4 (SbF6) by Raman spectroscopy and infrared spectroscopy. The determination of the crystal structures of the first three salts is also reported.

 Reactions of As4S4 with PF5, PCl5, BCl3, SO3, NbF5 , TaF5 and WF6 were shown to not proceed or, in the case of
PF5, to not produce a stable adduct. The action of AsF5
on compounds and mixtures of heavy main group elements
(e.g., Sb2Te3) of groups V and VI produced no new compounds
that were identified and generally just gave known homo-polyatomic cations of the chalcogens.

 Oxidation of As4S4 with the halogens (X) chlorine and bromine produced AsX3 and S2X2 while the reaction of SbCl5 with As4S4 or 1:1 As:Se fused mixtures produced SbCl3, AsCl3 and the salts SCl3 (SbCl6) and SeCl3 (SbCl6),respectively. The crystal structure of SCl3 (SbCl6) is reported here along with unit cell data for SeCl3 (SbCl6) and SBr1.2Cl1.8 (SbCl6) and the Raman data for all three compounds. Only AsSI was produced by the oxidation of
As4S4 by I2 in SO2 while a reaction between molten P4Se3
and I2 gave the new compound αP4Se3I2. Raman spectra for both AsSI and αP4Se3I2 were recorded as well as the 31P nmr spectrum for the latter.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Relationship Between Bitumen and Copper-Lead-Zinc Mineralization in the Mid-Silurian Carbonates in the Vicinity of Hamilton, Ontario

subject: Hamilton, lead, zinc, mineralization, Mid-Silurian, bitumen, carbonates

abstract:
 Previous workers in the Hamilton area have pointed out the occurance of lead and zinc mineralization within the Mid-Silurian carbonate beds. They also mentioned the existance of bitumens in these rock units.

 Analysis of 30 dolomite samples and separated bitumens by atomic absorption for Cu, Pb, Zn showed that the localization of the metals in the carbonates was controlled by the concentration of the bitumens in the rocks.

 Analysis of 5 bitumens samples by atomic absorption for Cu, Pb, Zn suggested that the bitumens act merely as a reducing agent and are not preferred sites for base metal accumulation.

abstract: Thesis

abstract: Bachelor of Science (BSc)


title: Project Information System - A Database Approach

contributor:
Masterson, J.S.
Computation

subject: projects, computerized, database, language, Management

abstract: In many organizations, the working activities of individuals are accounted for on the basis of projects to which they are assigned. Usually all such information and the descriptions of the projects are recorded manually during the advancement of each project. This primitive procedure is not efficient to maintain information for enabling ongoing project control and analysis of the allocation of personnel resources. Hence there is a need for a computerized system. Such a system has been designed and partly implemented by employing the CDC DMS-170 Database Management System using COBOL as the host language.

abstract: Thesis

abstract: Master of Science (MSc)


title: Interface Stability During Isothermal Ternary Phase Transformations

contributor:
Kirkaldy, J. S.
Metallurgy and Materials Science

subject: planar phase interfaces, morphologically unstable, phase transformations, isothermal ternary systems, precipitatematrix interface stability, dilute ternary systems, two-phase, diffusion couple, perturbation theory, alpha, beta

abstract: This dissertation is concerned with establishing the conditions under which planar phase interfaces are morphologically unstable during phase transformations in isothermal ternary systems. First, linear perturbation methods are employed in a detailed treatment of precipitatematrix interface stability for dilute ternary systems. Following this, the stability of the planar interface in a two-phase ternary diffusion couple is examined with the aid of perturbation theory. An experimental investigation into the stability of <alpha>-<beta> phase interfaces in the Cu-Zn-Ni system at 775°C is described. The results of this experimental study are shown to be in good agreement with the earlier theoretical predictions.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Analysis of Metropolitan Outmigration of Elderly Females In Canada: 1971-76

contributor:
Liaw, K. L.
Geography

subject: outmigration pattern, Canada, Canadian, Female, Elderly, CMA, Census Metropolitan Area, logit model, migratory, mobile, young, dispersion, male, migrants, metropolitanward

abstract:
 This paper analyzes the 1971-1976 outmigration pattern of the Canadian female elderly from the 23 Census Metropolitan Area's (CMA's). The migration is conceptualized as a three-level choice process and is represented by the logit model. The major findings are as follows:
(1) Elderly females are substantially less migratory than young females but are slightly more mobile than elderly males. In addition,, the elderly females in the Western region tend to be more mobile than those in other regions.
(2) Elderly females show less preference for the metro politan destinati ons than the young population; however, among the elderly, females have a stronger preference for metropolitan areas than males.
(3) In general, the metropolita~d outmiS!'ants' destination choice pattern is less dispersed for the elderly than for the young. Among the older persons, female migrants have a larger dispersion than male migrants in most CMA's.
(4) With respect to metropolitanward elderly migrants from the CMA's, the probability of choosing a particular destination is positively related to population size, brightness , and housing growth, and negatively related to the logarithm of di stance, cultural dissimilarity, coldness, and gross rent.
(5)Environmental variables are more important than the housing variables in determining the destination choice pattern of the elderly mi grants.

abstract: Thesis

abstract: Bachelor of Arts (BA)


title: A Three Dimensional Photoelastic Method of Analyzing The Stresses In Thick Walled Toroids

contributor:
Kardos, G.
Mechanical Engineering

subject: three dimensional, 3D, photoelastic, stresses, toroids, Bourdon Tubes, interal pressure, shear stresses,

abstract:
 A three dimensional photoelastic method of analyzing the stresses in toroids, such as Bourdon Tubes, is proposed in this thesis, The experimental techniques and procedures developed are documented in detail, The experimental method is used to study a thick walled toroidal shell under a uniform internal pressure.

 The principal stresses on the inside and outside surfaces of the shell were determined and from these the maximum shear stresses calculated. The experimental results are compared to Lame's solution of a thick walled ring under iniform internal pressure, a thin walled toroidal shell subjected to uniform internal pressure, and a long, straight thin walled cylinder with closed ends loaded by internal pressure.

abstract: Thesis

abstract: Master of Engineering (ME)


title: Petrology And Geochemistry of The 1308 Lake Sill, Beechey Lake Area, District of Mackenzie, Northwest Territories

title: Petrology of The 1308 Lake Sill, Beechey Lake Area, N.W.T.

contributor:
Burley, B.J.
Geology

subject: gabbroic intrusion, Goulburn, sediments, Bathurst trench, TV-1 scintillometer, petrographic, argillite, greywacke, Burnside River, crystallization, differentiation, lake sill

abstract:
 A gabbroic intrusion within the Goulburn group of sediments near the west margin of Bathurst trench was studied and mapped using a TV-1 scintillometer. Petrographic examination of the sill was carried out and geochemical whole rock and trace element data were obtained using X.R.F. methods.

 The 1308 Lake sill was injected conformably between the Western River (argillite/greywacke) and Burnside River (pink quartzite) units of the Goulburn group of sediments. The sill subsequently underwent minor fractional crystallization and differentiation. Generally the sill exhibits poor phase layering, but can be divided into six basic units.

1) Upper Chilled Margin Gabbro
2) Leuco-Micro-Syenite Lens
3) Diabasic Gabbro
4) Pyroxene Granophyre
5) Diabasic Gabbro
6) Basal Sheared Chilled Margin Gabbro These units are evident in this section and are distinguishable both modally and texturally. In most cases, variations in the chemistry and norms reflect the units mapped in the field. Comparisons have been drawn and theories incorporated from other gabbroic intrusions to help explain some features of the 1308 Lake sill.

abstract: Thesis

abstract: Bachelor of Arts (BA)


title: Statistical Methods for the Evaluation of a Cancer Screening Program

contributor: Clinical Epidemiology/Clinical Epidemiology & Biostatistics

subject:
Statistical methods
cancer screening

abstract:
Estimation of the sensitivity and specificity of cancer screening tests using data from population-level databases is complicated by the lack of independent confirmation of test results using a "gold standard''.   The true sensitivity and specificity are unknown and errors in measurement can occur due to subjective clinical judgment, technical imperfections or interpretational differences. A further complication is clustered data (such as patients nested within examiners within screening centre), which are common in population-based screening. We propose a cancer screening model that accommodates the partially unobserved disease status, clustered data structures, general covariate effects, and the dependence between exams.

The model is applied to the estimation of the diagnostic accuracy of mammography and clinical breast examination using a cohort consisting of women 50 to 69 years of age screened at the OBSP between January 1, 2002 and December 31, 2003. When offered in addition to mammography, we found CBE may benefit women using hormone therapy but not likely benefit women with dense breast tissues.

The thesis also discusses two measures of interest, the length of the pre-clinical state and the false negative rate. Two estimation procedures are proposed to model the pre-clinical state duration, the false negative rate of screening exam, and the underlying incidence rate in the screened population. Both methods assume the sojourn time follows a negative exponential distribution, but we consider two different forms for the false negative rate: 1) constant with time and 2) an exponential function to compensate for the fact that lesions should become easier to detect the closer they are to become clinically evident. The proposed methods are illustrated  with another cohort of women who were first screened through the OBSP between January 1, 2003, and December 31, 2004 and were followed up until December 31, 2009.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Bodies of Science: The Experiences of Human Research Participants of Health Studies

contributor:
Warry, W.
Anthropology

subject: health studies, policy makers, medical, anthropology, human, research, REBs

abstract:
 This dissertation examines my investigation of the experiences of participants of
university-based health research. My primary research questions were: (1) Why
do people participate in health research, despite its risks? (2) Why are people
asked to participate in health research? (3) What factors influence local research
environments? I employed a critical-interpretive medical anthropology
framework to investigate and describe three studies: a Phase 2a asthma drug
study, a Phase 1 oncology drug study, and a muscle regeneration study. I
followed each of these studies, conducting hundreds of hours of participant
observation and interviewing 31 participants multiple times during the course of
their enrolment. To learn about the organization and governance of university-based
health research I also interviewed researchers, research coordinators, and
ethics experts. In addition, I conducted participant observation at three different
research ethics boards (REBs) and two industry conferences. Participant
enrolment was significantly influenced by: belief in the "good" of medical
research, the enjoyment they experienced as former participants, and desire to
receive benefit, including remuneration and possible health benefits.
Participation often entails long hours, and much of this time is spent socializing
with the research team. Participants often develop trusting relationships with
the research team, and learn to adopt its scientific language, in addition to its
interests and perspectives. Thus, participants rarely question how research is
funded and who ultimately benefits from research. They also do not identify as
participants, but rather as volunteers or guests. This is a significant obstacle for
participant organization. Since they are not organized to voice their interests
collectively, REBs are responsible for protecting their interests. Research ethics
board focus almost exclusively on reducing risk and rarely address increasing the
potential benefit of researcher to the participants. I conclude my analysis with
recommendations for REBs, policy makers, and researchers.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Closed-loop Dynamic Real-time Optimization for Cost-optimal Process Operations

contributor:
Swartz, Christopher L.E.
Chemical Engineering

subject: Dynamic real-time optimization

subject: MPC

subject: Economic optimization

subject: Mathematical program with complementarity constraints (MPCC)

subject: KKT conditions

subject: Distributed MPC

subject: MPC coordination

abstract:
Real-time optimization (RTO) is a supervisory strategy in the hierarchical industrial process automation architecture in which economically optimal set-point targets are computed for the lower level advanced control system, which is typically model predictive control (MPC).  Due to highly volatile market conditions, recent developments have considered transforming the conventional steady-state RTO to dynamic RTO (DRTO) to permit economic optimization during transient operation. Published DRTO literature optimizes plant input trajectories without taking into account the presence of the plant control system, constituting an open-loop DRTO (OL-DRTO) approach. The goal of this research is to develop a design framework for a DRTO system that optimizes process economics based on a closed-loop response prediction.  We focus, in particular, on DRTO applied to a continuous process operation regulated under constrained MPC.  We follow a two-layer DRTO/MPC configuration due to its close tie to the industrial process automation architecture.

We first analyze the effects of optimizing MPC closed-loop response dynamics at the DRTO level.  A rigorous DRTO problem structure proposed in this thesis is in the form of a multilevel dynamic optimization problem, as it embeds a sequence of MPC optimization subproblems to be solved in order to generate the closed-loop prediction in the DRTO formulation, denoted here as a closed-loop DRTO (CL-DRTO) strategy.  A simultaneous solution approach is applied in which the convex MPC optimization subproblems are replaced by their necessary and sufficient, Karush-Kuhn-Tucker (KKT) optimality conditions, resulting in the reformulation of the original multilevel problem as a single-level mathematical program with complementarity constraints (MPCC) with the complementarities handled using an exact penalty formulation.  Performance analysis  is carried out, and process conditions under which the CL-DRTO strategy significantly outperforms the traditional open-loop counterpart are identified.

The multilevel DRTO problem with a rigorous inclusion of the future MPC calculations significantly increases the size and solution time of the economic optimization problem.  Next, we identify and analyze multiple closed-loop approximation techniques, namely, a hybrid formulation, a bilevel programming formulation, and an input clipping formulation applied to an unconstrained MPC algorithm.  Performance analysis based on a linear dynamic system shows that the proposed approximation techniques are able to substantially reduce the size and solution time of the rigorous CL-DRTO problem, while largely retaining its original performance.  Application to an industrially-based case study of a polystyrene production described by a nonlinear differential-algebraic equation (DAE) system is also presented.

Often large-scale industrial systems comprise multi-unit subsystems regulated under multiple local controllers that require systematic coordination between them.  Utilization of closed-loop prediction in the CL-DRTO formulation is extended for application as a higher-level, centralized supervisory control strategy for coordination of a distributed MPC system.  The advantage of the CL-DRTO coordination formulation is that it naturally considers interaction between the underlying MPC subsystems due to the embedded controller optimization subproblems while optimizing the overall process dynamics.  In this case, we take advantage of the bilevel formulation to perform closed-loop prediction in two DRTO coordination schemes, with variations in the coordinator objective function based on dynamic economics and target tracking.  Case study simulations demonstrate excellent performance in which the proposed coordination schemes minimize the impact of disturbance propagation originating from the upstream subsystem dynamics, and also reduce the magnitude of constraint violation through appropriate adjustment of the controller set-point trajectories.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Study of Open Orbits In Gallium, Cadmium, Zinc and Copper By An Induced Torque Method

contributor:
Datars, W. R.
Physics

subject: induced torque, amplitude, high field limit, k -trajectory, pseudopotential, anisotropic non-quadratic field dependence, metals, copper, zinc, quantum oscillations, coherence-effect modulation, magnetic breakdown

abstract:
 The theoretical treatment of the induced torque problem is discussed, and equations describing the functional form of the torque amplitude are derived on the basis of a model calculation valid in the high field limit. This functional form is applied to a detailed interpretation of the open orbit structure in gallium, cadmium, zinc and copper.

 An investigation of the open orbit structure in gallium at l.4°K using this technique has yielded direct information on the connectivity of the sixth-band hole surface. This surface supports a k(c)-trajectory for all field directions in the ab plane, except within 0.1° of the a-axis. A k(a)-trajectory of lower conductivity is reported over a 10° range of field direction centred (32°±2°) from the b-axis in the be plane. These data, in addition to the highly anisotropic amplitude and field dependence of the k(c) -trajectory, require that this surface contact the Brillouin zone boundary at both the k(a) -and k(c) -faces. The present data are compared with available models of the sixth band hole surface, and are found to be in excellent agreement with the predictions of recent pseudopotential calculations .  The possibility of magnetic breakdown in the k(c)-trajectory for B|| b-axis is discussed. Finally, a non-linear frequency dependence, and an anisotropic non-quadratic field dependence are understood to occur through the long mean free path and short skin depth parameters in gallium at l.4°K.

 In cadmium, the induced torque amplitude due to the [0001]-open trajectory tends to saturation at high field intensities for all observation directions. This effect is attributed to magnetic breakdown between the first-and secondhand hole surfaces through the spin·-orbit interaction energy
'gap near the H-symmetry point in the AHL plane. This magnetic breakdown effect is analyzed on the basis of a linear chain model and the theoretical curves of Falicov and Sievert. Detailed analysis indicates the possibility of two separate breakdown probabilities across the HL and HA gaps; for <1010> directions , breakdown fields of 10.8 k0e and (as low as) 0.72 k0e are indicated . A similar range of breakdown fields is indicated for all field directions in the (0001) plane.

 In zinc, the induced torque technique is used to investigate magnetic breakdown effects in the [0001]-trajectory for specific field directions in the basa l plane. These effects are attributed to the onset of partial breakdown between the monster and cap surfaces near the H-symrnetry points, for field intensities above 16 kOe. The linear chain model is shown to be an inappropriate description of breakdown effects in zinc. An onset field of 16 kOe for <1120> is determined; no breakdown is observed along <lOIO> below 20 kOe. In addition, magnetic breakdown effects occurring in the basal orbits of zinc were investigated. The general monotonic rise in torque amplitude with field intensities is fitted to the theoretical expressions of Falicov, Pippard, and Sievert. The giant quantum oscillations arising through coherence-effect modulation of the breakdown probability are shown consistent with earlier data.

 The technique is applied to a general survey of the various types of open orbits existing in copper, and the general applicability of the sample torque equations to both compensated and uncompensated metals is demonstrated.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Magnetic Susceptibility of Powdered SmPO4

contributor:
Stager, C.V.
Physics

subject: magnetic susceptibility, samarium orthophosphate, crystal field, cubic ssymmetry, phosphate, arsenates, vanadates, isomorphous compounds, crystallize, monoclinic, tetragonal

abstract:
 The magnetic susceptibility of samarium orthophosphate (SmPO4) has been measured over the temperature range from 0.4
to 270°K. A theoretical expression for the susceptibility has been developed assuming a crystal field of cubic symmetry and fitted to the experimental data.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Binding of a ^ Particle in Nuclear Matter and in ^He5

contributor:
Nogami, Y.
Physics

subject: overbinding, ^ particle, nuclear, spin-isospin, matter, energy

abstract: In this thesis, we are concerned with the outstanding problem of overbinding of a ^ particle in the spin-isospin saturated nuclear medium. The suppression effect in nuclear matter due to the repulsive core has been examined carefully and the single-particle-energy spectrum of the ^ particle is then derived. The two-channel formalism which takes account of the Σ^ conversion explicitly is used to study the binding of ^ in nuclear matter and in ^He5. With phenomenological ^N interactions which fit the low energy scattering data, it is shown that in this formalism the experimental binding energy of ^He5 can be reproduced.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Reflection And Heating Coefficients In Southern Ontario

contributor:
Davies, J. A.
Geography

subject: Reflection, heating coefficients, simcoe, Ontario, agricultural, atmospheric, postulate, Montieth, vegetated surfaces, radiation, solar radiation, simcoe horticultural experiment, crops, Budyko

abstract:
 Reflection and heating coefficients were measured during the
3 month summer season at Simcoe, southern Ontario. Contrasting agricultural surfaces and atmospheric conditions were used to analyse their effect on the reflection and heating coefficients. The results confirm the postulate of Montieth (1959a) that <alpha> is close to 0.25 for many vegetated surfaces. <beta> values were positive and there was a tendency for <beta> to approximate 0.22 for many of the vegetated surfaces. Finally it was shown that the radiation balance equation for Simcoe can be generalized into a linear function of solar radiation using the same constants that are applicable to many areas in the world.

abstract: Thesis

abstract: Master of Arts (MA)


title: Lifetimes of Excited States of Nuclei in the Mass Range 28<A<56 by Delayed Coincidence

contributor:
Prestwich, W.V.
Physics

subject: inter-multiplet, states, odd-odd, nuclei, coincidence

abstract: A study of the inter-multiplet Ml transition probability for states populated by the (n,γ) reaction in a number of odd-odd nuclei has been performed. Using a high resolution delayed coincidence system and specially developed calibration and data analysis techniques, lifetime measurements have been made for low energy transitions in 28Al, 32P, 40K, 46Sc, 52v and 56Mn. A theoretical model which uses the static magnetic dipole moments of the corresponding odd-A nuclei as the base states has been investigated and was shown able to produce a very satisfactory agreement with the experimental inter-multiplet B(Ml) values.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Some Impacts of Septic Effluent On Hydromorphic Soils

contributor:
Bunting, B. T.
Geography

subject: soil atmoshpere, soil physical parameters, coliform levels, ionic levels, Multivariate, fluxes, spectic effluent, soil fabric alterations, anaerobosis, elevated coliform, nitrate, chloride, sodium levels, ecological, health criteria

abstract: Measurements of soil atmosphere, soil physical parameters, coliform levels and ionic levels were made at 15 soil sites along Ancaster and Grindstone Creeks in winter, 1972-73 and July, 1973. Multivariate analysis of the data indicated large fluxes of septic effluent resulted in soil fabric alterations, anaerobosis, and elevated coliform, nitrate, chloride and sodium levels. According to ecological and health criteria, these hydromorphic soils have very serious limitations as processors and absorbers of septic effluent.

abstract: Thesis

abstract: Master of Science (MSc)


title: Biochemical Investigations On An Asporogenous Mutant Of Bacillus Subtilis

contributor:
Takahashi, I
Biology

subject: chromosome, Bacillus Subtilis, Sp-H12-3, Hg-Cs2SO4, DNA segments, m-RNA, physiological, biochemical, sporulation

abstract: Deletion in the chromosome of Bacillus subtilis strain Sp-H12-3 was demonstrated by Hg-Cs(2)SO(4) density gradient centrifugation. The base composition of the deleted DNA segments and transcription of m-RNA from these DNA segments were investigated. Physiological and biochemical studies of the mutant Sp-H12-3 yielded information on uridine derivatives which may be intimately associated with the process of sporulation.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Energy Levels in Samarium 151

contributor:
Johns, M.W.
Physics

subject: energy levels, beta, decay, Pm151, samarium, spectrometer

abstract: The energy levels of Sm151 populated in the beta decay of Pm151 have been studied with the aid of magnetic spectrometers. The internal and external conversion spectra were examined with a π√2 spectrometer of 50 cm radius. A Gerholm-type double lens coincidence spectrometer was used to perform electron-beta, electron-electron, electron-gamma and gamma-beta coincidence experiments. In addition, precise measurements of the transition energies obtained by Geiger and Graham (1962) with the Chalk River π√2 iron-free spectrometer are included. A decay scheme based on these results is proposed and speculations are made concerning the possible interpretation of the levels on the basis of the Nilsson model. The results are also compared with other recently published data on this decay.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Some General Methods of Solution Applied to Differential Equations Arising from Problems in Mathematical Physics

subject: differential equations, mathematical physics, coefficients, functions, polynomials

abstract:
(Page numbers are given in brackets after sub-headings.) Chapter 1 :-Application of operational methods of solution to ordinary differential equations with constant coefficients. Motion of helical springs --- Free vibration ( p.2 ) --- Forced vibration ( p.7 ) --- Resonance ( p.10 ) ----- Linked springs ( p.12 ) --- Analogous electrical problems ( P. 15 ). Appendix A :-Laplace Transformations. ( p.18 ) Appendix B :- Brief explanation of the operational methods of solution used in the chapter. ( p.19 ) Appendix C :- Example of partial fraction working. ( p.21a)
Chapter 2 :- Application of Fourier Series and of operational methods of solution to partial differential equations. Small transverse vibrations of a light elastic string ( p.22 ) Vibration of a string initially plucked at its middle point ( p.28 ) --- Alternative method of solution of the preceeding problem by operational methods ( p.31 ) --- Discussion of the shape assumed by the string at any time ( p.36 ) Chapter 3 :- Application of Bessel Functions to the solution of partial differential equations of the second order. Small vibrations of a light circular membrane ( p.39 ) Appendix A :- Transformation of the differential equation of motion from Cartesian to cylindrical coordinates. ( p.46 ).
Appendix B :- Note on roots of Bessel Functions. ( p.47 ) Appendix C :- Bessel Functions - Some important results applied in the chapter. p.48 ).
Chapter 4 :- Application of Legendre Polynomials to the solution of partial differential equations of the second order. Conduction of heat in a solid body ( p.50 ) ---------- Flow of heat in a solid sphere ( p.53 ). Appendix :-Statement of the Divergence Theorem used in
the chapter. ( p.61 ). Chapter 5 :- Example of Simultaneous Partial Differential Equations. The flow of electricity in a long imperfectly insulated cable ( p.62 ) ---- Analogous problem of the flow of heat in rod of small uniform cross section ( p.69 ).

abstract: Thesis

abstract: Master of Arts (MA)


title: CONTROLLED MODIFICATION OF SILOXANE OR HYDROCARBON INTERFACES USING ORGANOSILANES

contributor:
Brook, Michael
Chemistry and Chemical Biology

subject:
interfacial modification
organosilane

abstract:
Surfaces/interfaces are considered as one of the key factors that determine performance, and ultimately the application, of materials. In many cases, surface/interface modifications are required for desired properties, such as adhesion and wettability. Organosilanes have been widely used to alter surface/interfacial properties for many materials including metals, glass, and polymers, etc. However, controllable processes for surface/interfacial modification are desired.
This thesis aims to explore controllable paths for surface/interfacial modifications on siloxane or hydrocarbon-based materials using organosilanes. Further understanding about the methodologies for quantification of functional groups located at surfaces/interfaces is also within the scope of this thesis.
In this thesis, a comprehensive study of PDMS surface modification using thioalkylsilane coupling agents is described. An equilibrium silanization allowed the introduction of thiols on silicone elastomer surfaces under control and without damaging the surface. Two different titration methods for testing thiols in solution were developed and improved for quantification of thiol groups located at air-solid interfaces. The thiol-functionalized silicone could be further modified with maleic anhydride and/or with a variety of polymers and surfactants in a single step or two steps. A long term, stable hydrophilic surface was obtained after these modifications.
In this thesis, the modification of hydrocarbon-based materials is also described. A method based on the Piers-Rubinsztajn reaction was used to convert lignin into value-added chemicals, including monomeric/oligomeric aromatics and lignin composites. For the hard wood lignin, reduction of the ether bonds and silylation with hydrosilanes led to nearly complete fragmentation. The monomeric/oligomeric aromatics decomposed from hard wood lignin are easy to process as demonstrated by their excellent solubility in various solvents. Alternatively, softwood, which does not have an ideal structure for fragmentation, is effectively employed as “green filler” in silicones for lignin-based elastomer/foams. The partial (interfacial) reduction of hydrosilanes at lignin interfaces results in covalent linkage sbetween lignin and siloxane network, improving the interfacial miscibility. The softwood lignin, thus plays dual roles as a crosslinking and reinforcing agent. Formulations were readily developed to prepare silicone foams/elastomers by controlling processing parameters and methods. Lignin-based silicone elastomers could be obtained with additional solvent and casting in an open mold; lignin-based silicone foams could be molded in a volume-confined mold after extrusion.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Braided Stream Sedimentation In The South Saskatchewan River

contributor:
Walker, R. G.
Geology

subject: flood, south saskatchewan river, sandy bed, braid bars, sand flats, discharge, annual flood, downstream, upstream, ripples, sand waves, dunes, flow expansion, channel bends, channel junctions, channel widening, flow expansion, topography, troughs, sinuous-crested dunes, flood plain, crossbeds, deposits, lamination, sedimentation, river

abstract:
 In the study area, the South Saskatchewan River has a sandy bed (mean diameter .3mm) with irregularly-shaped braid bars termed sand flats. These range in length from 50 to 2000 m. The river has an average discharge of 220m^3/sec, with a mean annual flood of 1450 m^3/sec. The river has been dammed upstream of the study area since 1965, but little downcutting has occured.

 Ripples, sand waves and dunes are the equilibrium bedforms present . Ripples and dunes are well known , but sand waves are long , low bedforms with superimposed ripples, lack scour troughs, and occur at lower flow velocities than dunes . Foreset-type bars are also present , but are not equilibrium forms . They result from flow expansion around older topography. They occur at (1) channel junctions, (2) channel bends, (3) areas of channel widening, (4) places of vertical flow expansion . They deposit planar crossbeds.

 Large areas of the river have many sand flats with no major channels, and may even lack minor channels. These areas are termed sand flat complexes. Where a major channel curves around a sand flat complex, a large diagonal bar is deposited. It is mainly on the tops of these bars where new sand flats form.

 The major channels rarely exceed 5 m in depth, but may be 150m wide. They are floored by sinuous-crested dunes with sand waves and ripples along their margins. The dunes build up during floods (2 m maximum amplitude). Large dunes occur in the deeper channels.

 Three different morphologies of small sand flats, symmetric, asymmetric and side, have been recognized. Each type forms from a bar which becomes partly immobilized where it becomes emergent. The remainder of the bar front continues to advance around this emergent nucleus. The different morphologies result because of the control exerted by preexisting deposits on the shape of the initial bar.

 Larger sand flats lack these morphologies because they have been extensively modified. The major processes of modification are vertical, lateral, and upstream accretion by bars; linking of sand flats by bars; erosional action. The variable morphologies of larger sand flats reflect only their latest modification. The stratification of sand flats is mainly planar crossbed sets deposited by the bars.

 During the winter, a 60cm thick layer of ice covers the entire system. The sand flats are immobilized because their top layers of sediments are frozen. In some places, their surfaces are disrupted by fluid escape caused by high pore pressures generated by freezing. Flow proceeds down the channels under the ice. Rafting of cobbles and scouring around grounded ice blocks takes place at breakup.

 The facies sequences resulting from sedimentation in the river are mainly sandy. Those which are deposited by channels consist dominantly of trough crossbeds, but lone planar crossbed sets may be present, deposited by large bars. Facies sequences which include sand flat deposits have several sets of planar crossbeds stacked on top of one another. All sequences have a zone of small crossbeds and ripple cross-lamination near the tops, resulting from shallow water deposition. They are capped by one-half metre of muddy flood-plain deposits.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Chlorophyll A and Phaeophytin Determination in Intertidal Mudflat Sediments of the Minas Basin, Bay of Fundy, Nova Scotia

subject: chlorophyll A, phaeophytin, intertidal, mudflat, sediments,

abstract:
Abstract Not Provided
Thesis
Bachelor of Science (BSc)


title: Investigating the roles of local mucosal immunity and estradiol in the generation of protective T cell responses against secondary HSV-2 infections in the female genital tract

contributor:
Kaushic, Charu
Medical Sciences

abstract:
Genital herpes is one of the most prevalent sexually transmitted infections in the world and recent estimates indicate that over 500 million people are infected by herpes simplex virus type 2 (HSV-2).  Although women are more susceptible to HSV-2 infections than men and the female genital tract is the primary site of HSV-2 infection, little is known about the generation of protective immune responses in this distinct microenvironment and how these immune responses protect against genital HSV-2 infections in women.  Previous studies in our lab using an HSV-2 mouse model have found that protection against genital HSV-2 challenge in immunized mice correlates with the induction of inducible vaginal associated lymphoid tissues (iVALTs).  The appearance of these structures coincides with the clearance of the virus, which suggests that protective immune responses against HSV-2 could be generated in the genital mucosa itself, without the help of draining lymph nodes. In addition, these iVALTs primarily consist of CD4+ T cells, underlying the importance of identifying and characterizing the type and function of T cells that are present in the genital mucosa and how these T cells provide specific protection against HSV-2 challenge, which has not been examined.  In addition, previous studies have shown that estradiol (E2) has a protective effect against sexually transmitted viral infections, but the mechanisms by which E2 protects against these viral sexually transmitted infections (STIs) has not been examined.  Therefore, the work undertaken in this thesis determines the conditions under which the genital mucosa can generate protective immune responses against HSV-2 infection and also characterizes the T cell responses that are generated in the genital mucosa of immunized mice following HSV-2 challenge.  We also determined the conditions under which E2 enhances protection against genital HSV-2 infections and examined the mechanism by which E2 regulates protective T cell responses in the genital mucosa following HSV-2 infection.
We first examined whether local immunization could establish effective antiviral memory responses directly in the female genital tract (FGT), without the help of draining lymph nodes, following HSV-2 infection.  We found that even in the absence of secondary lymphoid organs (SLOs), mice immunized intravaginally (IVAG) with attenuated thymidine kinase-negative (TK-) HSV-2 were completely protected against genital HSV-2 challenge, but they showed delayed viral clearance and prolonged genital pathology post-immunization compared to WT mice.  Although local viral-specific antibody responses were compromised and T cell-mediated anti-HSV-2 responses were delayed in the absence of SLOs, the immune responses generated in the genital mucosa were effective in protecting against HSV-2 challenge.
Next, we determined whether immunization, either locally in the genital mucosa or distally via the nasal mucosa, with a non-replicating virus vaccine could establish protection against HSV-2 challenge, in the presence or absence of SLOs, to further understand the requirements for generating local effector responses in the genital tract.  To do this, we immunized WT and LTα-/- mice IVAG or intranasally (IN) with a subunit vaccine (HSV-2 gD plus CpG), a heat-inactivated virus vaccine (heat-inactivated HSV-2 plus CpG), or a live attenuated virus vaccine (TK- HSV-2).  All groups of mice were then challenged IVAG with WT HSV-2.  Mice immunized by either route, with non-replicating vaccine, were not protected against genital HSV-2 challenge and succumbed to infection.  However, treating WT and LTα-/- mice with E2 prior to immunization resulted in enhanced protection against HSV-2 challenge.
Lastly, we examined the mechanism by which E2 treatment leads to enhanced protection of immunized mice following HSV-2 infection.  We found that E2 treatment increased the recruitment of mucosal effector CD4+CD103+ T cells into the vaginal tract of immunized mice, following HSV-2 challenge.  In addition, E2 treatment upregulated Th17 cells in the vaginal tract of mice following HSV-2 challenge, which was accompanied by an early IFNγ+ Th1 response and a decreased TNFα+ T cell response compared to mock controls.
These results suggest that the use of highly immunogenic live-attenuated virus based vaccines delivered via mucosal routes can provide protection in the genital tract against subsequent genital HSV-2 infections.  However, if a less immunogenic vaccine formulation, such as a subunit or inactivated virus based vaccine, or a lower dose of the attenuated virus based vaccine is delivered, either locally or distally, additional mucosal adjuvants or hormones may be required to elicit protection in the genital tract.  Furthermore, the hormonal microenvironment during immunization should be a critical consideration in the development of mucosal HSV-2 vaccines as hormones present at the time of immunization may significantly alter the induction of protective immune responses in the female genital tract.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Neutron Radiographic Imaging Analysis

contributor:
Harms, A. A.
Engineering Physics

subject: radiography, neutron radiography, edge-spread function method, ESF theory, ESF, numerical approach, Monte Carlo methods, Monte Carlo

abstract:
 In analyzing the processes involved in neutron radiography, there is a need for a well-defined mathematical structure which can simultaneously be used in practical situations without great difficulty. In this report, the edge-spread function method of analysis is considered in some detail. The basic theory is developed, and both the general and the specific viewpoint are considered, in terms of the mathematical functions used. The usefulness of ESF theory in predicting optical density patterns is illustrated. Specific applications of the theory are developed; in particular, studies of image resolution and unsharpness are undertaken.

 To determine whether or not ESF methods are a good representation of the physical situation, some alternate methods which consider radiography from a more basic viewpoint are developed. The first of these is a strictly numerical approach, where experimental data is examined without specifying a model for the image formation process; a matrix formulation suitable for characterizing an image is developed.

 The second alternate method involves the use of Monte Carlo methods; this allows the incorporation of more realistic parameters into the analysis. For example, screen-film separation and object scattering of neutrons, and their effects on the image, are evaluated. Finally, a two-dimensional analysis of a simple problem is considered, with the end result being a confirmation of the usefulness of ESF theory.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Changes in Insulin Resistance in Trained Athletes Upon Cessation of Training

contributor:
MacDougall, J.D.
Toews, C.J.
Adapted Human Biodynamics

subject: insulin, trained, athletes, cessation, glucose, metabolic, plasma

abstract:
 This study was designed to investigate possible changes in insulin sensitivity (IS) with cessation of training. Six endurance trained athletes were studied at 12, 60 h and 7 days following cessation of training. In-vivo IS was established by a glucose clamp
technique (Greenfield et al. Diabetes 30, 1981) and expressed as the metabolic clearance rate of glucose (MCR) in ml. plasma cleared kg-1. min-1. At 12 h after the last training session the mean MCR was 15.6+1.8 compared with 7.8+1.2(p<0.01) in age and weight matched
sedentary controls. The MCR decreased to 10.1+1.0 after 60 h and decreased significantly to 8.5+0.5(p<0.05) after 7 days of detraining. In-vitro IS was measured by determining the insulin binding of fractionated young erythrocytes by the method of Polychronakos et al. (Clin. Inves. Med.4,14B,1981). Insulin binding was 10.4+0.9% at 12 h and decreased significantly to 8.1+0.7%/4xl0^9 cells after 60 h of detraining (p<0.001). In conclusion: 1) detraining of endurance athletes resulted in a rapid decrease in IS. After 7 days, glucose MCR reached values indistinguishable from sedentary controls. 2) changes in IS observed may be partially
mediated by alterations in insulin binding to receptors. 3) since the high IS observed with endurance athletes on the initial test disappeared shortly after cessation of training, it is probably an acute effect of the last exercise bout rather than a chronic effect of training.

abstract: Thesis

abstract: Master of Science (MSc)


title: A Relative Method for Determination of Nuclear Decay Rates

contributor:
Kennett, T.J.
Fritze, K.
Chemistry

subject: relative, decay, half-lives, isotopes, nuclear

abstract: The performance of a relative decay rate measurement technique was investigated. Determinations of the half-lives of the isotopes copper-64 and ruthenium-97 in various chemical states were attempted as illustrations of the use of the method. Applications of the technique are suggested.

abstract: Thesis

abstract: Master of Science (MSc)


title: Observations of the Beach Environment of Southwest Devon Island, Northwest Territories with Special Reference to the Role of Ice

contributor:
McCann, S.B.
Geography

subject: open water, Radstock Bay, ice, beach environment, sediment, geomorphic, seawater

abstract:
 The open water season of Radstock Bay is less than three months
long and varies considerably from year to year. The break-up and ablation
sequence of the bay is regular and systematic, commencing with a period of
snow melt and run off and continuing until the dramatic evacuation of the
ice. This evacuation is dependent on the ice coverage of Lancaster Sound.
The ice foot, a feature found often on arctic beaches was found to be
larger in areas of more shallow sloping beaches. A sediment size analysis
revealed a trend of diminuation of grain size from S. to N. reflecting
net sediment transport in that direction. The two major geomorphic events
of the 1971 open water, were two storms, both of which had winds from the
S.E. that generated 1.0 meter waves which moved sediment from S. to N. The
importance of a small pack of ice in the nearshore zone in inhibiting wave
action was noted during one of these events. The freeze-up sequence
progressed slowly after the advent of sub-freezing temperatures until the
temperature of the seawater reached its freezing point, whereupon the rapid
covering of the bay with ice ensued.

abstract: Thesis

abstract: Master of Science (MSc)