title: Precipitation of Phosphates in Sewage with Lanthanum: An Experimental and Modelling Study

contributor:
Norman, J. D.
Chemical Engineering

abstract:
Canada and the United States by the "Great Lakes Water Quality Agreement" have designated that the discharge of phosphates in sewage to the Great Lakes will be controlled. In the majority of cases, chemical precipitation is the treatment method to be used. The selection of the chemical dosage needed is empirical and requires that extensive experimental studies be carried out at each wastewater plant.

The problem of estimating the chemical dosage is approached in this work on a more fundamental basis. The precipitation of phosphates with lanthanum is assumed to be representative of a chemical system at a metastable equilibrium. The dosage which results in the desired aqueous phosphate concentration at this state is estimated with an equilibrium model of the system. This model includes the reactions of major inorganic species found in wastewater.

Lanthanum is an efficient precipitating agent which causes a low residual phosphate concentration to result, even when added in quantities based upon the stoichiometric requirements. Also, lanthanum can be recovered by an economically viable process and recycled.

The solubility products of lanthanum, ortho-, pyro- and tripolyphosphate, lanthum hydroxide and carbonate and the stability constants of the hydroxide and polyphosphate ion complexes were measured. The experiments were carried out in distilled water at ion concentrations typical of the magnitude to be used in an actual treatment process. With this information, and solving the complex chemical equilibria problem for a set of over fifty separate reactions, it is shown that the extent of precipitation of ortho- and polyphosphates from a municipal wastewater can be accurately predicted. A computer program was written to predict the lanthanum dosage required for a specific residual of dissolved phosphates given the water quality of the wastewater expressed as the total aqueous concentrations of ortho- and polyphosphates, calcium, magnesium, carbonates, sodium, chloride, sulphates and pH.

abstract: Doctor of Philosophy (PhD)


title: Structural Studies on Nuphar Alkaloids

contributor:
MacLean, D.B.
Chemistry

subject: Chemistry Chemistry

abstract:
The mass spectra of several quinolizidine alkaloids of known structure, isolated from species of Nuphar luteum, have been studied. High resolution mass measurements have been used to characterise fragmentation patterns capable of differentiating between substituents in rings A and B of the quinolizidine system.

The stereoisomeric relationship between the thiospiran Nuphar alkaloids, thiobinupharidine and neothiobinupharidine, has been examined. A three-dimensional structure has been proposed for thiobinupharidine on the basis on its spectroscopic properties. An X-ray study has confirmed this structure and also established the absolute configuration of thiobinupharidine.

The structure of three new alkaloids, nupharolutine, thionupharoline, and neothiobinupharidine sulphoxide, have been established on the basis of mass spectral and p.m.r. data.

The steric course of sodium borodeuteride reduction of hemiaminals of thiobinupharidine in absolute ethanol solution has been investigated. Significant differences have been observed for both the degree of deuterium incorporation and for the stereoselectivity of deuterium incorporation when compared to those results reported for analogous reductions in methanol solution. The transient intermediacy of an alkoxyborodeuteride ion has been proposed to explain these results.

abstract: Doctor of Philosophy (PhD)


title: Strength of Block Masonry Walls Subject to Lateral Loading

contributor:
Drysdale, R. G.
Civil Engineering

subject: Civil and Environmental Engineering

subject: Other Civil and Environmental Engineering

subject: Civil and Environmental Engineering

abstract:
Provisions for the design of masonry walls is subject to uniformly distributed pressure normal to the surface of the wall differ significantly from country to country. These differences may be attributed both to differences in design philosophy and to a general lack of conclusive or widely accepted experimental and analytical research. Most of the previous research in this area was concerned with brick masonry and with practical rather than well defined support conditions. Also, the available design methods were not accurate or rational. Therefore, this study was initiated to investigate the flexural behaviour of hollow concrete block masonry both experimentally and analytically and to assess the design methods for laterally loaded walls.

The experimental program included 30 full scale wall tests representing different support conditions and aspect ratios. In addition, stack bonded prisms and wallettes were used to determine the flexural tensile strengths. The full scale tests were performed using a test facility designed to accommodate tests of masonry panels up to 6.0 m long by 3.6 m high and to provide well defined support conditions. The observed behaviours of the walls were compared to other walls of the same series and to other tests to investigate the effects of variability, aspect ratio, support conditions, and the presence of either precompression along the top panel or precracking near the panel center.

A nonlinear finite element model capable of reproducing the observed behaviour of the walls was developed and used to extend the knowledge of masonry wall behaviour to include untested conditions and configurations. In this model, the anisotropic nature of the masonry, the nonlinearity due to cracking, and the effects of the transverse shear were taken into considerations. Also, the existing biaxial failure criteria were examined and proposed macroscopic biaxial failure criterion was incorporated in the finite element model to predict the strengths and the failure modes for masonry assemblages. This criterion accounted for the anisotropic and composite nature of masonry and was based on physical interpretations rather than being strictly a phenomenological criterion.

Finally, the available design methods were compared using the extended data from the analytical model and design a method based on elastic plate theory was proposed. This method was rationally developed to predict first cracking and failure capacities for masonry panels simply supported on three or four sides for a wide range of aspect ratios.

abstract: Doctor of Philosophy (PhD)


title: A Numerical Approach to the Solution of the Supersonic Flow Field in the Exit Plane of High Turning Angle Turbine Blades

contributor:
Wade, J.H.T.
Mechanical Engineering

subject:
Mechanical Engineering
Mechanical Engineering

abstract:
The power output from a high turning angle turbine blade passage depends on many factors and the most important of all is the appropriate pressure distribution along the pressure and suction surfaces of the blades. The operation of a fully choked passage requires the specification of the proper operating pressure ratio to avoid the formation of any compression waves after the geometric throat which would otherwise generate a total pressure loss for the system.

With the advancement of computational methods, the two-dimensional supersonic flow field existing after a choked passage is elaborately analysed to avoid the adverse effect of compression waves on the blade performance. For different pressure ratios the characteristic waves as well as the pressure distribution are presented which give a theoretical prediction for the presence of a possible shock wave after the geometric throat of the passage. The shock free operation of the passage definitely increases the power output of the cascade. The stream tube method of pressure distribution is extended for generating the characteristic waves covering the entire supersonic flow field existing near the trailing edge of the fully choked passage of a high turning angle turbine blade passage.

abstract: Master of Engineering (ME)


title: The Lichtenbaum Conjecture at the Prime 2

contributor:
Kolster, M.
Mathematics

subject: Mathematics Mathematics

abstract:
The Analytical Class Number Formula, a classical result of Dirichlet, asserts that two important transcendental invariants associated to a number field F, namely the first non-zero Taylor coefficient of the Dedekind zeta-function, ζF, at 0 and the regulator of the group of unites of F differ by a rational number. Moreover, this rational number is the quotient of two algebraic invariants of F, namely the ideal class number and the order of the group of the roots of unity in F. The Lichtenbaum Conjecture attempts to exhibit the same type of relation between the first non-zero Taylor coefficient of ζF at 1 - m for m ≥ 2 and the Boral regulator in K-theory. They differ by the quotient of the orders of the torsion parts of consecutive higher K-groups (the even K-groups appear as generalizing the ideal class group, while the odd ones appear as generalizing the group of units).

The study of this conjecture is done at each prime p using p-adic Chern characters from K-theory to étale cohomology and an interplay between étale cohomology duality results and Iwasawa theory results. Using a different regulator the Lichtenbaum Conjecture has been proved at all odd primes for all abelian number number fields by Kolster, Nguyen Quang Do and Fleckinger. We develop similar methods and succeed to obtain a description of the 2-powers appearing in the formula for the case when m is odd. We also note that a motivic context is possible for the formulation of the Lichtenbaum Conjecture.

abstract: Doctor of Philosophy (PhD)


title: Ion Beam Mixing and Electrocatalysis of Platinum-Iron Alloys

contributor:
Thompson, D.A.
Smeltzer, W.W.
Materials Science

subject:
Materials Science and Engineering
Other Materials Science and Engineering
Materials Science and Engineering

abstract:
The experiment work pertaining to this thesis can be divided into two parts: a) The study of the ion beam mixing process in the platinum-iron system and b) Electrocatalysis measuremnts on the mixed platinum-iron alloys. The ion beam mixing was studied using a 120 keV Fe+ ion over a rang of temperatures from 298K to 523K. A thin film of platinum was evaporated onto an oxide free substrate of iron to form a bi-layer sample. In order to check whether the interface was clean and oxide-free, Auger electron spectrometry was used along with sputtering. The mixing was studied primarily using RBS. The TEM was also used to characterize the samples before and after mixing.

At low temperatures (<373 K), the mixing is very small and found to take place by collisional processes. At higher temperatures (>473 K) iron moves rapidly into the platinum. The activation energy for the platinum migration into the iron was found to be ~0.5 eV. This suggests that the vacancy mechanism is operating about 423 K. The films produced by mixing at low temperatures are highly stressed and there are a considerable amount of twins formed. It was also found that the grain size increases with dose and temperature.

The surface concentration Pt in the mixed film is high ~90%. This results in an improvement of ~25% in the overvoltage for the ion beam mixed films compared to an iron electrode. Ion beam mixed films were found to be more stable than iron electrodes simply coated with films with an evaporated platinum layer. This appears to be the result of the improved adhesion between the platinum and iron as a result of the ion beam mixing process. For unmixed samples, an oxide layer is able to form on the iron surface at the platinum./iron interface, possibly because of cracks in the platinum layer, and this results in platinum pealing off the electrode leaving just the iron electrode.

abstract: Doctor of Philosophy (PhD)


title: Applications of the Quantum Theory of Atoms in Molecules to Chemical and Biochemical Problems

contributor:
Bader, Richard F. W.
Chemistry

subject: Chemistry Chemistry

abstract:
The quantum theory of atoms in molecules (QT-AIM) is a generalization of quantum mechanics to open subsystems. The theory enables one to study the properties of atoms or functional groups within a molecule, recovering the empirical observation that they exhibit characteristic and additive contributions to every molecular property. This thesis applies theory to explain and predict experiment. In this work, atomic and group properties were shown to provide an excellent basis for the construction of quantitative statisical models which accurately predict the physicochemical properties of the amino acides and uncover regularities in the genetic code. The transferability and addivity of atomic properties were exploited to develop a method of assembling large molecules from buffered fragments, a method which reduces the computational effort and - as a result - brings large biological molecules within theoretical reach. The buffered fragments method was applied to obtain accurate properties of key opiod molecules. The additivity of atomic properties applies to any and all molecular properties including, for example, dielectric polarization. The dielectic polarization of a crystal was shown to be reducible to a sum of the polarization of its composing cells taken together with a sum of the dipoles arising from the charge transfer between neighbouring cells. The problem of aromaticity has been recast in terms of the pair densities in conjunction with QT-AIM, an approach that was shown to explain and predict several chemical and spectroscopic properties of polycyclic aromatic hydrocarbons. The criteria of bonding were revisited and applied to provide a clear-cut answer in a case where distance alone - as a criterion for bonding - provides ambiguous answers.

The thread tying this work together is the philosophy of "reductionism" in the narrow sense that the whole (e.g. a molecule or a crystal) is nothing but the sum of its spatially bounded non-overlapping parts (atoms). By resorting to this philosophy one not only gains a deeper insight into the physical basis of chemistry but is capable of accurately predicting experiment as well.

abstract: Doctor of Philosophy (PhD)


title: Effects of Anisotropies of the Electron-Phonon Interaction and the Fermi Surface on Electronic Properties of Aluminium

contributor:
Taylor, D. W.
Physics

subject: Physics Physics

abstract:
We have made a theoretical investigation of some of the transport properties of Aluminium. Our calculations include fully (a) the real Fermi Surface in the 4-OPW model of Ashcroft, (b) the electron-phonon matrix element with 15-OPW mixing for the electronic states and (c) the details of the variations of the Fermi velocities on the Fermi Surface (FS).

This is the first calculation to go beyond a spherical surface and single plane wave description of the electron-phonon interaction in Aluminium. We obtain results for the mass-enhancement parameter for electrons on the Fermi surface, the superconducting energy gaps, the transport lifetimes as they enter in the electrical resistivity and thermal resistivity. Results for the Hall coefficient and effect of phonon-drag on the electrical resistivity and thermopower are also obtained. We have investigated the effect of a small amount of non-magnetic impurities on the Hall coefficient and Deviations from Mathieson's Rule. For all these effects a great deal of agreement is obtained with experimental data.

abstract: Doctor of Philosophy (PhD)


title: Spatial and Temporal Variation in the Distribution of Radiation in a Mature Corn Canopy

contributor:
Davies, J. A.
Geography

subject: Geography Geography

abstract:
A study of the spatial and temporal variability of global solar, net solar and net radiation in two plots of corn, seeded differently, was undertaken using a moving tramway sampling system. Horizontal frequency distributions of radiant flux density revealed a systematic variation dependent on canopy structure.

A modified exponential model was developed as an empirical solution to the problem of estimating radiation fluxes in plant canopies. Since the extinction coefficients are dependent on present data its validity must await independent evaluation by other workers.

SOLCOMP, a simple layer model for global and net solar radiation was developed from theoretical considerations. This model performed well and illustrates that it is possible to model the radiation regime in a crop with a simple, theoretically-based construct using a small number of easily obtained input parameters. A further development, NETCOMP, suitable for estimating net radiation in the canopy showed potential but could not be fully tested due to lack of information on canopy temperature regimes.

abstract: Doctor of Philosophy (PhD)


title: Development of Controlled Release Drug Delivery Systems

contributor:
Stöver, Harald D.
Zhu, Shiping
Chemistry

subject: Chemistry Chemistry

abstract:
The newly emerged biotechnology of liposome-based drug delivery has drawn great interest in research and pharmaceuticals. Lipsomes are potential candidates to carry highly toxic drugs to target cells in order to minimize the damage to normal cells and side effects. In the past two decades, extensive work has improved the stability of phospholipid lipsomes in physiological fluids as drug carriers.

My research on developing controlled release drug delivery systems started with the synthesis of a highly reliable anchor for water-soluble polymers, which will serve as an anchor with a high affinity towards lipid bilayers and can be monitored by fluorescence. A new family of hydrophobic building block, namely cholesterol and fluorescence. A new family of hydrophobic building block, namely cholesterol and fluorescence group, was prepared and characterization. The conformation study suggests that intramolecular hydrogen bonds form via amide proton of these compounds in methanol-d3 and DMSO-d6. Furthermore, an efficient synthetic route was developed to synthesize the corresponding pyrenylbutyl cholestrol lysine derivative.

These functional hydrophobic building blocks were successfully attached to water-soluble polymers such as poly(N-isopropylacrylamide). Solution properties of the modified polymers were investigated by fluorescence, time-resolved fluorescence, and dynamic light scattering. The cholesterol bearing PNIPAM exhibited the lower critical solution temperature (LCST), which was close to that of the precursor polymer. The polymers formed micellar aggregates in water via inter or/and intrapolymeric associations, which depended on the polymer architecture and solution tempeprature.

Interaction of phospholipid and nonphospholipid liposomes with these thermoresponsive polymers was followed in order to develop controlled release systems based on cholesterol-bearing poly(N-isopropylacrylamide) coated liposomes. The strong interaction between the polymer and liposomes was found via fluorescence and gel-filtration chromatography measurement. As expected, the cholesterol-bearing polymers remained on the liposome surfaces as increasing temperature up to 60°C. In contrast, above the LCST of PNIPAM, octadecyl group modified PNIPAM escaped from lipsosome surfaces and left liposome unprotected. Interesting results were also found in the study of temperature controlled release and target fusion of these polymers coated liposomes.

In addition, controlled release systems based on hybrid polymeric nanoparticles formed by self-assembled cholestrol-bearing pullulan and poly(N-isopropylacrylamide) (PNIPAM) were studied. The hybrid nanoparticles further proved that cholesterol was a reliable anchor, which remained in hydrophobic microdomains of the hybrid nanoparticles in the studied temperature range from 20 to 45°C. In comparison, octadecyl group modified PNIPAM escaped from hybrid nanoparticles at the temperature above the LCST of PNIPAM.

Finally, these hydrophobic building blocks were attached to polysaccharide, hyaluronan (HA), to develop targeting delivery systems. Synthesis, characterization, solution properties of cholesterol bearing HA and interaction of the polymer with liposomes were conducted. The highly reliable liposomes as site-specific carriers were developed by coating the cholesterol-bearing hyaluronan onto lipsomes.

abstract: Doctor of Philosophy (PhD)


title: Ordered Topological Vector Spaces and Groups

contributor:
Husain, Taqdir
Mathematics

subject: Mathematics Mathematics

abstract:
We introduce three new classes of ordered topological vector spaces and investigate some of their properties. We show that they are good enough for the validity of the analogues of the Banach-Steinhaus theorem for sets of positive linear mappings, and this helps us obtain some results about positive Schauder bases. We use to advantage one of these classes of spaces to give an affirmative answer to a question raised in ([35]) about the order-bounded sets in the tensor products of ordered locally convex spaces.

We prove some results on the continuity of sublinear mappings of ordered vector spaces equipped with the order bound sc-topology (see the text for the definition).

Finally, we prove a type of closed graph theorem for ordered topological abelian groups.

abstract: Doctor of Philosophy (PhD)


title: Higher Order Core Polarization Corrections to the Effective Nuclear Interaction

contributor:
Sprung, Donald W. L.
Physics

subject: Physics Physics

abstract:
Various higher order core polarization corrections to the effective nuclear interaction, suggested by Kurson have been calculated for mass 18 and mass 42 nuclei. The corresponding spectra resulting from these correction were compared with each other and with experiment.

The bare nucleon-nucleon interactions used in the calculation were of two different forms. For the one interaction, the G-matrix elements of Kahana, Lee and Scott derived from their separable nucleon-nucleon potential, were used. For the other, matrix elements of the interaction were derived in a phase-shift approximation ot McMaster. In a certain approximation these are the free reaction matrix elements. The effects of the 2 forces were compared.

The schematic model of Brown and Bolsterli was extended to these higher order core polarization corrections and it was found to corroborate the results of the detailed, more realistic calculation.

abstract: Doctor of Philosophy (PhD)


title: On some Classes of Balanced Graph Designs

contributor:
Rosa, A.
Mathematics

subject: Mathematics Mathematics

abstract: Necessary and sufficient conditions for the existence of special types of balanced graph designs, namely, balanced bipartite designs, resolved balanced bipartite designs, balanced tripartite designs and balanced circuit designs, are investigated. Given a set of parameters, the necessary conditions for the existence of a design with these parameters are obtained, and to find out whether these conditions are also sufficient, we attempt to construct a collection of base blocks which generate the design. When such a collection cannot be found, we proceed to prove that the particular design does not exist. Several infinite series of designs have also been constructed.

abstract: Doctor of Philosophy (PhD)


title: Processing of ELT Signals for Search and Rescue Satellite Aided Tracking (SARSAT) using the MEM and FFT

contributor:
Carter, C.R.
Electrical Engineering

subject:
Electrical and Electronics
Electrical and Electronics

abstract: The proposed methods of search and rescue (SAR) of mobile platforms use low altitude polar orbiting satellites to detect signals emanating from emergency locator transmitter (ELT) systems on board the distress platform. The uplink transmission receives a doppler shift due to the radial velocity of the satellite. Extracting the doppler from the signal is necessary for calculating the position of the ELT system. These ELT units were originally designed for reception by ordinary hand held receivers and detection by the human ear. For this reason the transmitters employ a distinct type of modulation often referred to as a chirp. Detection and estimation of the doppler by signal processing is complicated by this swept modulation. This dissertation compares two methods of spectral estimation, namely, Fourier analysis (in the form of an FFT algorithm) and the maximum entropy method (MEM) for application to ELT signals. The signals to be processed are divided into two categories, single and multiple signals. Multiple signal processing is necessary when two or more ELT systems are transmitting simultaneously and the time separation between transmissions is small enough to cause overlapping of signals in time. Results indicate that the enhanced detection capability by using the MEM offers a significant improvement in processing signals from an ELT.

abstract: Master of Engineering (ME)


title: The Inferential Basis of Perceptual Performance

contributor:
Milliken, Bruce
Psychology

subject: Psychology Psychology

abstract: Prior exposure to a stimulus often speeds responding to that stimulus on a future occasion. Moreover, under some conditions, a previous encounter with a stimulus actually leads to slower responding to that stimulus. These "positive" and "negative" repetition effects are frequently interpreted as directly reflecting the activation state of abstract representations of knowledge (e.g., Paap & Noel, 1991; Tipper, 1985). This view has been challenged by other research suggesting that the effect of repetition depends on the appropriateness (or inappropriateness of prior processing for meeting current task demands (e.g., Jacoby, 1983; Neill & Mathis, 1998). In a series of experiments, I demonstrate that interferences people make about the source of fluent processing can also modulate the effect of repetition on perceptual performance. These findings establish that the same inferential process that is known to guide decision-making in other cognitive task domains, such as memory and categorization, contributes to performance on simple perceptual tasks as well.

abstract: Doctor of Philosophy (PhD)


title: Polyethylenimine Filled Membranes

contributor:
Childs, Ronald F.
Chemistry

subject: Chemistry Chemistry

abstract:
The fabrication, properties and performances of polyethylenimine pore filled and pore coated membranes are presented and discussed in this thesis. The membranes were prepared by an in-situ cross-linking process that involved filling the pores of a porous polypropylene host substrate with a solution of branched polyethylenimine and a diepoxy cross-linker of known concentration. The filled membrane was sandwiched between two polyethylene terephthalate sheets, to prevent solvent evaporation, and a cross-linked polymer network was formed within the porous microstructure of the host membrane.

Several cross-linkers were chosen based on their size, rigidity and hydrophobicity to cross-link polyethylenimine. A small, hydrophilic cross-linker- ethylene glycol diglycidyl ether- produced clear, space filling gels that had large swelling capacties by absorbing many thousand times its weight in water when immersed in aqueous solutions of varying pH. An oligomeric cross-linker- polypropylene glycol diglycidyl ether- produced colored space filling gels that exhibited moderate swelling abilities in aqueous solutions of varying pH. A rigid, hydrophobic cross-linker- bis-phenol A diglycidyl ether- produced gels that exhibited dimensionsal contraction (syneresis), scattered light and exhibited low swelling abilities.

Polyethylenimine cross-linked with ethylene glycol diglycidyl ether (PEI-EDGE) is hydrophilic and forms a hydrogel when swollen with water. The physical properties of hydrophobic polypropylene membranes were thus changed to hydrophilic upon the incorporation of the cross-linked polyethylenimine gel. The polyethylenimine gels in the membrane although formally neutral can acquire a charge by deprotonation of water, or addition of acid, due to the basicity of the aliphatic nitrogens. The membranes were very effective in the nanofiltration of ionic solutes because of the charge in the polyethylenimine gel. The rejection of the ionic feed exhibited Donnan exclusion behavior because the rejections of the ionic solutes were greatly dependent upon the valency of the respective co- and counter-ions and sucrose, a neutral solute, was not rejected. Co-ion rejection increased with an increase in ion valency and conversely, counter-ion rejection decreased with an increase in ion valency. Rejections of NaCl could be observed at high pH's, indicating the gels possessed a significant charge concentration over a large range of pH. The permeabilities of PEI-EDGE filled membranes could be fit to a modeled permeability curve calculated from a hydrodynamic gel permeability model developed by Alicja Mika and Ron Childs of McMaster University.

Membranes filled with polyethylenimine cross-linked with polypropyleneglycol diglycidyl ether (PEI-PODGE) exhibited a morphology distinctly different from the PEI-EDGE filled membranes. Laser fluorescence confocal and environmental scanning electron microscopy showed the presence of PEI-PODGE gel coatings on the outer walls of the hose substrate whereas a smooth, space filling gel morphology was seen in PEI-EDGE membranes. The permeability data suggested the existence of a gel plug in the central depths of the host substrate despite the microscopy evidence of coating. The PEI-PODGE membranes, however, exhibited fluxes that were higher than the EDGE cross-linked membranes due to the smaller thickness of the gel plug. The permeabilities of the PODGE cross-linked membranes, therefore, did not fit the modeled permeability curve. The low salt rejections observed in the PEI-PODGE membranes were attributed to concentration polarization of ionic solutes accumulated in the large cavities on the large membrane-feed interface.

Membranes filled with polyethylenimine cross-linked with bis phenol A diglycidyl ether (PEI-BADGE) exhibited unusually high fluxes and low salt rejection. The high fluxes and low salt rejections were consistent with the heterogeneity observed in the morphologies of the bulk PEI-BADGE gels and the effects heterogeneity has on flow through gels. As a result of the effects of heterogeneity, the permeability of PEI-BADGE filled membranes did not fit the modeled permeability curve.

A modification of the pore filling fabrication procedure resulted in the formation of pore-coated ultrafiltration membranes. Motivated by the coated morphology observed in the PEI-PODGE filled membranes, pore coated membranes were fabricated by a controlled evaporation of solvent from a solution onf polyethylenimine and cross-linker filled in the pores of a host membrane. The coating imparted a hydrophilic nature to the originally hydrophobic host substrate and the coating could not be removed even when extracted in boiling methanol for a few days. The membranes had very high fluxes typical of ultrafiltration membranes. The fluxes, however, gradually decreased as a function of both the composition and amount of feed passed through the membrane. Drying the membrane restored the flux to a higher value; however, the decrease in flux was observed upson subsequent testing suggesting the coated layer was swelling into the pores.

abstract: Doctor of Philosophy (PhD)


title: Studies on Categories of Universal Topological Algebras

contributor:
Choe, T.H.
Mathematics

subject: Mathematics Mathematics

abstract: In this thesis we study categories of universal topological algebras and topological partially ordered sets. Topologically algebraic functors are introduced. It is shown that most of categories usually studied in general topology, universal algebras and universal topological algebras can be covered by this concept. In addition, we consider extensive subcategories of various categories of Hausdorff topological algebras and continuous homomorphisms. In particular, we obtain a method to construct extensive subcategories which is applied to categories of topological partially ordered sets and topological lattices.

abstract: Doctor of Philosophy (PhD)


title: Paradise Lost and Seventeenth-century Pageantry

contributor:
Dale, J.
English

subject:
English Language and Literature
English Language and Literature

abstract:
Recent scholarship has added to our knowledge about the court masque, reinforcing its significance for the literature of the sixteenth and seventeenth centuries. Milton's Comus has profited from such re-assessment so that its high valuation as dramatic literature need no longer be regarded as incompatible with its success as a court masque. The new seriousness of approach to the court masque in general and Milton's Comus in particular provides the impetus for an examination of the rest of Milton's poetic output for the purpose of tracing there the influence of his experience with the complimentary court entertainment.

The court entertainment was encomiastic in intent, this encomium being patterened according to certain conventions. Paradise Lost, which praises God, uses a number of these conventions. Contrary to usual epic practice, Milton does not immortalize worldly conquests and compliment the statesmanship of his nation's leaders. Early notions of a British epic, to use the Arthurian or other indigenous material, were abandoned in favour of a work to celebrate the heavenly king and the spiritual kingdom. In the finished poem epic structures are interpreted in ways suggestive of the influence of court pageantry. Inconium of the heavenly king is expressed in the God-centred structure of Paradise Lost. The whole action of the poem focuses on the throne of the omniscient viewer. The angels sing and dance about this throne as the court danced before royalty in the court entertainment, and even creation is the setting for "a Race of Worshippers" (VII.63C). A foil to the glory of Heaven, provided in the parodic activities of the fallen angels in Hell, suggests the conventions of the antimasque and the comedy of misrule. The victorious reign of Christ is celebrated, as many a pageant celebrated the reign of a seventeenth-century king, in a tournament. A mock battle in which no one is maimed, this culminates in the triumphal entry of Christ himself in a pageant chariot, symbolically banishing, rather than waging battle with, the forces of evil. In Satan's pilgrimage to earth even the traditional epic wanderings are transformed into an allegoric process. The devices of the court entertainment inform the action of the poem, which is made up of processions, ceremonies and masques. The scenic spectacle, too, is influenced by the theatrical effects and iconography of royal pageantry.

One might expect Heaven and Hell to be presented in terms of allegoric theatre, but in Paradise Lost even the garden itself is a golden world which works according to the pastoral conventions that so often informed court entertainments. Adam and Eve are the poem's legendary rulers. As he describes the pomp of the prelapsarian kingdom, Milton relies on a knowledge of contemporary pageantry. Here such pageantry expresses the perfection of the most perfect earthly kingdom of all. Referring to a legend often used to glorify the British court, Milton says of Paradise: "Hesporian Fables true, / If true, here only" (IV.250-51). To see Paradise Lost in the context of the contemporary pageantry and masque theatre is to see it not as history reconstructed, but as historic incident transmuted through the use of a series of literary devices into encomiastic fiction. The fictional world of the poem is designed to justify the workings of God's creation: it glorifies the providence of the omnipotent creator.

abstract: Doctor of Philosophy (PhD)


title: Interactions of Dietary and Waterborne Copper in Rainbow Trout, Oncorhynchus Mykiss

contributor:
Wood, Chris M.
Biology

subject: Biology Biology

abstract:
In mammals, copper is an essential yet potentially toxic trace element if accumulated in excess of cellular requirements. These conflicting properties demand a tight regulation of Cu, both at the cellular and organismal levels. Unlike mammals, fish can assimilate significant amount of Cu from the water via the gills, in addition to the dietary uptake via the gastrointestinal tract. The relative contributions of branchial and gastrointestinal routes of uptake in Cu homeostasis and toxicity in fish remain largely unknown. Therefore this thesis examined the interactions between dietary and waterborne routes of Cu uptake as they relate to homeostasis and toxicology of Cu using the freshwater rainbow trout, Oncorhynchus mykiss, as a model system.

Copper is clearly essential to fish based on both growth response and body Cu status in rainbow trout. Direct measurements of unidirectional Cu uptake following exposure of rainbow trout to conditions depleted and elevated in Cu showed up-regulation and down regulation of branchial Cu uptake, respectively. Thus Cu uptake from the water responds to body Cu status and there is an inteaction between dietary and waterborne Cu uptake in the maintenance of body Cu balance. Under conditions of background water and dietary Cu levels, diet is the more important route of Cu uptake, accounting for about 90% of the Cu intake. However, during deficiency, waterborne Cu uptake may contribute up to 60% of the Cu requirement. Interestingly, while waterborne Cu uptake responds to acclimation to elevated waterborne Cu, as well as elevated dietary Cu, gastrointestinal Cu uptake does not. It thus appears that the gut serves for bulk acquistion of Cu while the gill performs homeostatic fine-tuning via adjustment of branchial Cu transport mechanisms. Moreover, the response of branchial uptake mechanisms to Cu acclimation suggests the presence of at least two types of Cu transporters at the gill epithelium.

A linkage between Cu and sodium (Na+) uptake and homeostatic mechanisms in fish gills was unveiled. Elevating dietary Na+ reduced unidirectional uptake rates of Cu, and up to 95% of the reduction in Cu uptake was explained by parallel reduction in waterborne Na+ uptake. This co-variation between Na+ and Cu uptake strongly suggests that Cu and Na+ share uptake pathways, possibly the apical Na+ channel. Furthermore, long-term exposure to elevated dietary Na+ reduced Cu accumulation in the liver as well as the short-term binding of Cu to the gills. These findings have important implications including the use of dietary Na+ to protect against Cu toxicity both im fish and humans.

From a toxicological perspective, this thesis research uncovered new areas for consideration in the development of water quality criteria for Cu. One method currently under development for determining realistic site-specific water quality guidelines is the Biotic Ligand Model (BLM). The US Environmental Protection Agency has provisionally adopted the BLM as a site-specific modification to the current acute Ambient Water Quality Criteria for Cu. The tenet of BLM is prediction of the metal bound to the gill that results in toxicity in water of known chemistry. Several water chemistry parameters including Ca2+, Na+, dissolved organic matter, and pH greatly modify metal binding to the gill and hence toxicity. This thesis shows that dietary quality factors such as Cu and Na+ content, and acclimation to waterborne Cu influence the binding of Cu to the gill biotic ligand. Future development of the BLM should therefore consider dietary factor and acclimation effects.

Lastly, this thesis provides direct evidence that dietary metal uptake and diet quantity are important in toxicology and environmental risk assessment for metals. Food quantity influences fish growth and metal uptake thereby affecting whole body and tissue Cu concentrations such that lower Cu concentrations do not necessarily reflect lower Cu accumulation but can, in fact, represent growth dilution. Therefore, using body metal burdens for biomonitoring and risk assessment is meaningful only if dietary metal intake and feeding regimes are taken into account.

abstract: Doctor of Philosophy (PhD)


title: Development of Larval Photobehaviour as a Paradigm to Indentify Mutations that Affect Nervous System Development and Function

contributor:
Campos, Ana R.
Biology

subject: Biology Biology

abstract:
In Drosophilia neurogenetics, one uses mutational approaches to dissect the function and development of the nervous system. This approach has been very successful in the isolation of many single gene mutations that affect adult fly behaviour. However, it has been estimated that 30-50% of all genes in Drosophilia mutate to result in adult inviability. This encouraged us to consider the larval stage as a platform for indentifying mutations that affect the nervous system through the use of larval behaviour assays.

A part of this thesis describes the design, standardization and demonstration of behaviour assays. The assays employed both a population of animals and individual larva to study their response to light. Using these assays we screened a collection of mutagenized recessive lethal strains to identify new genes that affect nervous system function. The development of these assays enable the demonstration that larval visual system uses many of the same genes that participate in the transduction of light in the adults. Lack of response to light after genetic ablation of larval photoreceptors was also demonstrated.

A partial automation of one of the individual larval assays was also established. Using this, an expeditious screening of 50 mutant lines was carried out. This pilot screen resulted in the isolation of candidate lines that show defects in larval photo-response and locomotion.

This study also focused on a single behavioural mutant line and called tamas. Through genetic analysis and direct sequencing of pre-existing alleles that belong to this locus it was determined that the tamas gene codes for mitochondrial DNA polymerase catalytic subnit (tamas/pol γ-α/POLG). Mutations in this gene cause defects in nervous system development and locomotory behaviour. We also carried out phenotypic analysis of mutants with lesion in the gene that codes the accessory subunit of the mtDNA polymerase (pol γ-β). Pre-existing alleles in this gene were indentified first through genetic analysis, next, through direct sequencing the mutations in this gene were confirmed. These experiments consituted the first phenotypic analysis of mutants in the mitochondrial DNA polymerase for any metazoan.

abstract: Doctor of Philosophy (PhD)


title: Offensive Shadows: Vision and the Spinster in Charlotte Bronte's Villette

contributor:
Ferns, Doctor J.
English

abstract: Graham Bretton's comment to Lucy Snowe, single heroine of Villette (1853), that she is "'a being inoffensive as a shadow'" serves a fitting epigraph to Bronte's last novel (403). Having explored the experience of a single life to varying degrees in her previous works, The Professor (pub. 1857), Jane Eyre (1847), and Shirley (1849), Bronte announces with the death of M. Paul that Villette tells the story of the spinster. Indeed, the first-person narrative of Bronte's heroine expounds the single woman's experience to an extent unknown in the literature of the time. In keeping with Bronte's representation of her own spinsterhood, Villette depicts a woman facing a hostile environment which leaves her feeling unsure of her own substantiality. For, as discussed in chapter one of this study, the marginal position of the middle-class spinster in the mid-nineteenth century meant that she was reduced to a shadow. At the same time, she was vilifed for the insubstantial body by which she was set aside, the very terms of her marginalization used to diminish her. Through theories of vision outlined in Michael Foucault's Discipline and Punish (1979) and Luce Irigaray's This Sex Which is Not One (1985), I explore the untenable position of the single woman in the mid-nineteenth century as represented in Villette. Although many studies acknowledge Lucy's difficulties with spinsterhood, none regards her spinsterhood as the determining factor in a narrative which explores such themes as identity and sexuality. Chapter two examines the social mechanism which produces Lucy's difference, while chapter three investigates Lucy's relationship to the treacherous world of flesh. In the end, the spinster in Villette emerges above all else human, a sign that Bronte, as spokesperson for the shadow-band, has gone on the offensive.

abstract: Doctor of Philosophy (PhD)


title: Modeling and Rehabilitation of Non-Ductile Spatial RC Columns

contributor:
Ghobarah, A.
Civil Engineering

subject:
Civil and Environmental Engineering
Civil and Environmental Engineering

abstract:
In frame structures, the multi-directional motion of an earthquake has a significant effect on the structure response. The columns, especially those at the building corners, are subjected to biaxial bending from combined longitudinal, transverse, and torsional motion of the structure, with added axial loads due to overturning. Moreover, the variation of the axial forces may be independent of the variation of the other lateral forces.

The non-ductile response of structural elements, particularily columns, has been the cause of numerous failures during earthquakes. The non-ductile behaviour of reinforced concrete columns arises from different causes such as insufficient anchorage length and bond for the longitudinal steel bars with concrete, insufficient confinement, or inadequate shear strength.

The objective of this research program is to analytically and experimentally evaluate the non-linear behaviour of non-ductile reinforced concrete columns under lateral cyclic deformations. The experimental data was used to verify the analytical predictions.

The analytical phase of this study included the development of an upgraded 3D beam-column element based on lumped plasticity modelling. The model accommodates flexural response by quadrilinear force-deformation relationship, and shear response by strength and stiffness degrading relationship. The model takes into account the effect of axial load variation on lateral deformation and its interaction with biaxial moments and shear, which is an important contribution.

The 3D model was validated using experimental data available in the literature by several independent researchers for reinforced concrete columns. The calculated and experimetnal results were encouragingly close, especially considering the complexity of the response. The effect of different axial load variation paths on the response of cyclically loaded columns was studied.

A new analytical procedure to obtain the moment-rotation and force-deflection relationships for reinforced concrete columns was developed. These relationships were used as input data for the 3D element. This procedure uses the basic mechanical and geometrical properties of the element. This procedure uses the basic mechanical and geometrical properties of the element. It takes into consideration the effect of bond-slip of tensile bars, buckling of compression bars as well as flexure and shear deformations. This procedure was verified using available experimental data. The comparision showed good agreement. A parametric study to evaluate the effect of variation in section and material properties was also conducted.

The experimental phase of this study included testing three reinforced concrete short columns under cyclic lateral loads and constant axial load. The first specimen, which represents columns designed according to current code (CSA A23.3-94), failed in a non-ductile shear manner. The second specimen was identical to the first one but rehabilitated using anchored carbon fibre reinforced polymers (CFRP). A significant increase in the displacement ductility of the column was achieved. The third specimen represents a non-ductile short column designed according to pre-1970 codes and rehabilitated using anchored CFRP wraps. Increased ductility was achieved. Two different techniques to reduce concrete bulging at column sides were evaluated in the two rehabilitated specimens; namely, by using through steel rods and fibre anchors. Both techniques proved to be effective.

abstract: Doctor of Philosophy (PhD)


title: A Computer Aided Design Package For Time Series Analysis

contributor:
MacGregor, J.F.
Wright, J.D.
Chemical Engineering

subject:
Chemical Engineering
Chemical Engineering

abstract:
Robert Frank Moore: A Computer Aided Design Package for Time Series Analysis. M.Eng. Thesis, McMaster University, Hamilton Ontario, February 1982.

Control problems often require a reasonable and adequate model for forecasting or control. An interactive computer package is presented which allows the iterative determination of a stochastic and transfer function model for single input/single output experimental data. Note that time series analysis techniques present various quantitative measures of model adequacy for this type of model. User familiarity with time series analysis is essential in the determination of a reasonable, parsimonious model during an interactive session with this package.

The interactive program provides initial diagnostic tests for the data to aid the estimation of parameters for a user selected model form. The Marquardt non-linear least squares procedure is available to improve the initial parameter estimates. Information for diagnostic testing of the model residuals is then displayed. The option for iteration back to the point of model form selection is available.

A multivariable analysis problem may be resolved in a stepwise manner using a non-iterative version of the time series package. This version fits a user selected model to the data and provides diagnostics on the model residuals. The computer package is presently functional on a VAX 11/750 computer. All graphical display characteristics are suitable for a Tektronics 4025 terminal. Programming for the package is in FORTRAN77.

abstract: Master of Engineering (ME)


title: Neocortical Long-Term Depression and Depotentiation in the Adult, Freely Moving Rat

contributor:
Racine, Ronald J.
Psychology

subject: Psychology Psychology

abstract:
Information is believed to be stored in the brain by constructing new neural circuits, and these circuits are shaped by changes in the strength of the synaptic connections between the neurons making up the circuit. According to most theories of memory, new circuits can be formed by either increasing or decreasing the strength of synaptic connections. Bidirectional modifications in synaptic efficacy are also central components in recent computer simulations of learning and memory. While long-term potentiation (LTP) has been the focus of extensive research into the mechanisms underlying information storage in the mammalian brain, long-term depression (LTD) and depotentiation, its depressive counterparts, have not. Furthermore, most of the LTD research has involved the used of anaesthetized animals and in vitro slice preparations, making it more difficult to determine the role of this synaptic phenomenon in learning and memory in the intact behaving animal.

This thesis provides the first detailed examination of: 1) the induction and decay of both LTD and depotentiation in the neocortex of the awake, freely moving animals; 2) the effects of N-methyl D-Aspartate receptor (NDMAR) blockade on the induction of LTD, LTP, and depotentiation (NMDA receptor activation is known to play a major role in most forms of LTP); and 3) the interactions between these synaptic phenomena.

LTD was expressed as a significant reduction in the amplitude of both short- and long-latency field potential components. Depotentiation was expressed as a long lasting decrease in the amplitude of a previously enhanced late component. LTD was found to be greater in magnitude and longer lasting when the conditioning stimulation was repeated. However, unlike LTP induction, the conditioning stimulation was equally effective whether spaced over hours or days.

NMDA receptor antagonism blocked LTP induction and instead produced a depression effect similar to LTD. Unlike LTP, LTD and depotentiation were found to be NMDAR-independent in the neocortex of the freely moving rat.

LTP and LTD are both reversible phenomena and LTD-inducing stimulation can modulate the effects of LTP-inducing stimulation. LTD-inducing stimulation, when delivered following to LTP-inducing stimulation, attenuates the induction rate for potentiation. LTD and depotentiation may play important roles in the ongoing experience-induced modification of neuronal connectivity. Furthermore, these results are consistent with the hypothesis that potentiation and depression reflect the physiological instantiation of a bidirectional learning rule.

abstract: Doctor of Philosophy (PhD)


title: Horizontal Budgeting: Results-based Budgeting and the Co-ordination of Horizontal Policies in Canada and the United States

contributor:
Carroll, Barbara Wake
Political Science

subject:
Political Science
Political Science

abstract: This dissertation examines how governments may use results-based budgeting to co-ordinate horizontal policies, and how a country's regime type may affect the incidence and success of such efforts. A rational choice institutional approach is used to frame the relations between "guardian" budget-makers in central budget agencies and "splender" civil servants in line departments. We undertake a quantitative analysis of primary budget documents of selected departments in the federal governments of Canada and the United States, and confirm our findings through a series of interviews with budget-makers, departmental officials and academics in both countries. Our findings suggest that, regardless of regime type, results-based budgeting is rarely used to help co-ordinate horizontal policies, for two main reasons. First, results-based budgeting's potential to co-ordinate is limited by methodological difficulites. In particular, it is often difficult to fully understand the casual theory behind programs and to fully measure all the relevant aspects of programs. Second, the motivation of budget-makers to so use results-based budgeting is limited by political disincentives. In particular, there are many disincentives to publicize the true objectives of programs and to reveal the actual performance of programs. On balance, the theoretical potential of and incentives to adopt "horizontal budgeting" is often outweighed by the practical difficulties and disincentives. This research contributes to existing knowledge of the public administration of expenditure budget-making by highlighting similarities between current budgeting systems in Canada and the U.S. and the program budgeting experiments of the 1960s and 1970s, by exploring the potential and incentives to use results-based budgeting to co-ordinate horizontal policies, and by advancing the research methodology of comparative budgeting studies. Furthermore, by increasing our knowledge of the process of budgeting, we also inform understandings of the contents of budgets, and so inform understandings of the contents of a wide range of policies and programs.

abstract: Doctor of Philosophy (PhD)


title: PEO/Poly(Vinyl Phenol-Co-Styrene Sulfonate) Aqueous Complex Formation

contributor:
Pelton, Robert H.
Chemical Engineering

abstract: High molecular weight poly(ethylene oxide) (PEO) is an effective flocculant in the papermaking process. The performance of PEO can be greatly enhanced in the presence of second polymeric component. This second component is called cofactor in paper technology literature. In this thesis, poly(vinyl phenol-co-styrene sulfonate (PKS) is chosen as a model cofactor. The mechanism for complex formation between PEO and PKS, the transport properties of PEO/PKS complexes, the relationship between PEO/PKS complex formation and flocculation are discussed. PEO mainly interacts with aromatic groups of PKS through hydrogen bonding and hydrophobic interactions. The widely proposed hydrogen bonding mechanism between phenolic hydroxyl group and ether oxygen is investigated by comparing the complex formation, flocculation performance between PEO/PKS and PEO/poly(styrene-co-styrene sulfonate). Phenolic content, salt, temperature and PEO molecular weight affect the complex formation and flocculation efficiency. A hydrophilic, sterically stabilized and negatively charged colloidal model, dextran sulfate modified precipitated calcium carbonate, is developed to mimic the solution properties of fillers in papermaking flocculation. This work gives a better understanding about PEO/cofactor flocculation mechanism.

abstract: Doctor of Philosophy (PhD)


title: Protein Adsorption to Polyethylene Oxide-Grafter Surfaces

contributor:
Brash, J.L.
Chemical Engineering

abstract:
The objective of this work was to study and gain a better understanding of the mechanisms and factors that mediate how effectively grafted polyethylene oxide chains promote protein repellency.

A polyurethane-urea was used as a substrate to which PEO was grafted. This material was synthesised by conventional methods and characterised using water contact angles, XPS and AFM. A grafting protocol was developed based on methods found in the literature, involving the introduction of isocyanate groups into the polyurethane surface followed by reaction of amine- or hydroxyl-terminated PEO. Surfaces grafted with PEO chains of various lengths were prepared and characterised by water contact angles, XPS and AFM. The data showed that the amine-terminated polyethylene oxide gave higher PEO graft densities than the hydroxy-terminated polyethylene oxide. Direct measurements of the grafting density of PEO via radiolabeling resulted in only qualitative data due to experimental problems associated with the measurements.

Protein adsorption studies were performed with the PEO-grafted surfaces. Several factors anticipated to have an impact on the effectiveness of the PEO-grafted surfaces in repelling proteins were examined. The levels of protein adsorption generally decreased with increasing PEO graft molecular weight. The reduction generally reached a maximum at a PEO MW of 2000. Adsorption levels on surfaces with 5000 and 200 MW grafts were usually similar. Adsorption levels on surfaces prepared with amino-terminated PEO were in agreement with the surface characterisation data that indicated higher levels of grafted PEO.

On most of the surfaces, there was little or no effect of protein size on the ability of the PEO grafts to inhibit protein adsorption. However a surface grafted with PEO of MW 550 adsorbed smaller proteins more extensively that larger proteins. The data also showed little or no effect of protein isoelectric point on PEO surfaces with long PEO-grafts probably due to surface charge "masking" by the PEO grafts. Surfaces with shorter PEO grafts, however, showed lower levels of adsorption for the more highly charged proteins. This effect may have been due to electrostatic protein-protein repulsion as protein accumulated at the interface.

Experiments to investigate the effect of temperature on protein replusion by the PEO-grafted surfaces showed that the properties of the proteins themselves play a large role in determining levels of adsorption and that the solution properties of PEO (inverse temperature dependence) could not explain the effects observed.

Results of experiments using multi-protein systems showed that the PEO-grafted surfaces did not repel proteins selectively: only the total quantity of protein adsorbing to the surfaces was affected.

abstract: Doctor of Philosophy (PhD)


title: Properties and Applications of the Metal-Insulator-Semiconductor (MIS) Tunnel Diode

contributor:
Shewchun, J.
Electrical Engineering

abstract:
This work describes a theoretical and experimental investigation into the electrical properties and possible device applications of the three layer Metal-Insulator-Semiconductor (MIS) structure when the insulating layer is very thin (<60A). Under these conditions, current can flow between the metal and the semiconductor by quantum mechanical tunneling processes. This work is limited to the case where the semiconductor is not degenerately doped.

To aid in the discussion of the properties of this structure, its electrical behaviour is simulated by describing the transport processes through the semiconductor and the insulator regions mathematically and solving the resulting system of mathematical equation numerically. Solutions for both the AC and DC properties of the structure are obtained in this way. Using these solutions as a guideline, a general theoretical framework is established which allows the device properties to be predicted when parameters such as the work function of the metal contact, the insulator thickness, the properties of surface states at the insulator-semiconductor (IS) interface, the device temperature, and the dopant type in the semiconductor are varied. Particular importance is placed upon the charge conditions in the semiconductor at the IS interface under zero bias conditions. Depending upon whether this region is strongly inverted, depleted, or accumulated, the dominant component of the diode current tends to flow between the metal and the minority carrier energy band, surface state levels, and the majority carrier energy band in the semiconductor respectively. Correspondingly, the devices are classified as minority carrier, surface state, and majority carrier diodes. In addition to this classification, a distinction between "equilibrium" and "non-equilibrium" devices is made. In the former, the insulator layer is thick and the device currents small while in the latter, this layer is thinner and the enhanced current flows cause the semiconductor to depart significantly from thermal equilibrium. Experimental measurements upon the metal-silicon dioxide-silicon system are used to demonstrate the validity of this theory and also demonstrate the utility of the classification scheme described.

Non-equilibrium diodes are of particular interest because of their possible device applications. Majority carrier non-equilibrium devices exhibit current multiplication properties which are discussed theoretically and measured experimentally. These make the devices of interest in transistor structures and in such applications as photo-diodes with internal multiplication properties. Minority carrier non-equilibrium devices are shown both theoretically and experimentally to possess properties similar to p-n junction diodes under reverse and small to moderate forward bias. Since they are considerably simpler to fabricate, they have possible application as replacing junction devices in a number of applications such as those as injecting contacts, photo-diodes, or members of photo-diode arrays. One particularly promising application is to direct energy conversion using the electron-or photo-voltaic effect. For an energy conversion situation using the radioisotope Pm147 as the primary energy source it is demonstrated that the predicted higher conversion efficiency of the MIS tunnel diode compared to the p-n junction diode can be experimentally realized.

abstract: Doctor of Philosophy (PhD)


title: Bias in Avoidance-Yoked Eyelid Conditioning Comparisons

contributor:
Siegel, S.
Psychology

subject: Psychology Psychology

abstract:
Yoked groups have often been used as controls against which to assess the effects of a contingency between a response and some event. For example, Moore and Gormezano (1961) used a yoked control group in an experiment designed to assess the effects of an avoidance contingency in human eyelid conditioning. For the avoidance subjects in their study, an eyelid closure during the CS-US interval precluded the delivery of the air puff US. Each avoidance subject was given a yoked partner who received the air puff, without regard to his responding, on those trials when his avoidance partner received it. In this way, the avoidance and yoked control groups were equated for number and pattern of USs, and differed only with respect to the instrumental contingency.

Moore and Gormezano's (1961) finding was that the avoidance group reached a higher asymptotic level of conditioned responding than the yoked group. However, Church (1964) has argued that the results of such instrumental-yoked comparisons are ambiguous since any effects due to the contingency are confounded with the effects of a bias in the design favoring the instrumental subject. The purpose of the present research was to evaluate Church's argument that bias arising from within-pair mismatching in effectiveness contributes to the avoidance-yoked difference obtained in eyelid conditioning.

Three rabbit eyelid conditioning experiments involving a total of 228 subjects are described. Pre-yoke matching (Experiment 1), multiple yoking (Experiment 2), and reciprocal yoking and self-yoking (Experiment 3), procedures were implemented. The results of the between-subject, and within-subject, avoidance-yoked contrasts in these experiments support Church's (1964) conceptualization of a yoked subject as one that receives more, or fewer, shocks, and in a different pattern, that it would if delivery of shocks were contingent upon its own behavior. Hence, the major conclusion that is drawn from these experiments is that differences in acquisition performance between avoidance and yoked subjects in the rabbit eyelid conditioning preparation are the result of bias. The findings of this investigation suggest that the instrumental-yoked differences obtained in other research programs may also reflect bias in the yoked control design, and not the effects of the instrumental contingency per se.

abstract: Doctor of Philosophy (PhD)


title: Distribution of Some Noble Metals in Sulfide and Oxide Minerals in Strathcona Mine, Sudbury

contributor:
Crocket, J. H.
Geology

subject: Geology Geology

abstract:
Neutron activation analysis has been carried out to determine the concentrations of Pd, Ir, Pt, and Au in coexisting pyrrhotite-magnetite-chalcopyrite-pentlandite from deep zone ore of Strathcona mine, Sudbury. The concentration profiles of Pd, Ir, and Au from disseminated sulfide along the 2750 cross-cut of the mine were also measured.

It has been shown that the dominant mode of occurrence of these metals is solid solution in host sulfide and oxide minerals at average concentration ranges from 1.5 p.p.m. for Pt to 3 p.p.b. for Ir. The distribution of the noble metals is considered in terms of magmatic temperature and subsolidus events. At magmatic temperatures, all four noble metals are found to fractionate fairly strongly into pyrrhotite solid solution: at subsolidus conditions, Pt strongly prefers chalcopyrite and Pd and Au, pentlandite. The basis of these effects are discussed in the light of thermodynamic, molecular orbital, and diffusion theories.

The implications of the concentration profiles of Pd, Ir, and Au in the petrogenesis and origin of the Strathcona sulfides are discussed.

abstract: Doctor of Philosophy (PhD)


title: Speed, Flow and Capacity Relations on Multilane Highways

contributor:
Allen, Brian L.
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract:
Traffic engineers rely heavily upon the fundamental relationships between the variables speed, flow and capacity which characterize the traffic stream. Accurate knowledge of the operational behaviour of roadway traffic inevitably enhances the reliability of planning and design. Because of the importance of basic relationships to traffic engineering, this study was undertaken. The study involves investigating the important relations between speed, flow and capacity currently existent for uninterrupted flow on multilane highways in Ontario. The results are compared with information established by both the Highway Capacity Manual (HCM) and Polytechnic Institute of New York (PINY). Comparisons are made of 5-minute and 15-minute hourly flow rates, and calculated truck equivalents with those currently recommended. In addition, the impact of adverse weather conditions on fundamental speed-flow relationships and how occupancy (density) relates to speed and flow were investigated.

Results of the study indicate that there is a significant difference between relations presently in use and those existing on roadway facilities. In particular, capacity was found to be in excess of 2000 passenger cars per hour and speeds were noted as being higher than established values.

abstract: Master of Engineering (ME)


title: The Formation and the Five-Fold Degenerate Rearrangement of Lewis Acid-Complexed-5-Acyl-1,2,3,4,5-pentamethylcyclopentadienes

contributor:
Childs, R.F.
Chemistry

subject: Chemistry Chemistry

abstract:
This thesis describes the preparation of some bicyclo[3.1.0]-hexenyl cations with different substituents at C6 and a study of their degenerate rearrangements. The preparation of both isomers of 6-ethyl-1,2,3,4,5,6-hexamethylbicyclo[3.1.0]hexenyl cation was achieved by the photoisomerization of l-ethyl-1,2,3,4,5,6-hexamethylbenzenonium ion. A new cation, 1,1,2,3,4,5-hexamethylbenzenonium ion was prepared and characterized.

The preparation of a series of 5-acyl-1,2,3,4,5-pentamethyl-cyclopentadienes has been developed in an attempt to generate bicyclo[3.1.0]hexenyl cations with the hydroxy group at C6. The protonation of 5-acyl-1,2,3,4,5-pentamethylcyclopentadienes results in the formation of dications which have been characterized by p.m.r. and uv spectroscopy. These dications are stable below 0º but at higher temperatures undergo a fragmentation reaction where protonated pentamethylcyclopentadiene is generated. This provides a convenient synthetic route for pentamethylcyclopentadiene.

5-Acyl-1,2,3,4,5-pentamethylcylopentadienes react with various Lewis acids to generate σ-complexes in which the Lewis acid is bonded to the carbonyl group. The zwitterions have been characterized using infrared and nuclear magnetic resonance spectroscopy.

The Lewis acid-complexed-5-acyl-1,2,3,4,5 pentamethylcyclopentadienes exhibit temperature dependent p.m.r. spectra. The averaging can best be explained in terms of a five-fold degenerate rearrangement in which the Lewis acid-complexed ketone group migrates around the periphery of the five-membered ring. The rates of circumambulation were determined by comparing the experimental and calculated p.m.r. spectra. The rate of automerization is dependent upon the nature of the acyl group as well as the Lewis acids used. A linear free energy relationship exists between the rates of circumambulation of AlCl3-complexed aromatic ketones and the para-substituent constant, the magnitude of the reaction constant ρ being 4.64 (correlation coefficient 0.999).

These results have been discussed in terms of a mechanism which involves a bicyclic zwitterion as the transition state for the degenerate rearrangement. The possibility of a homoconjugative interaction between the electron-deficient C6 and the occupied orbitals of cyclopentadiene is discussed.

abstract: Doctor of Philosophy (PhD)


title: Mechanisms of Ligand Exchange in Complexes of Cobalt, Nickel and Zinc

contributor:
Eaton, D.R.
Chemistry

subject: Chemistry Chemistry

abstract:
One of the simplest types of reactions encountered in inorganic chemistry involves the exchange of a molecule coordinated to a metal ion (the ligand) with another molecule free in solution. This type of reaction is fundamental to much of synthetic inorganic chemistry and also constitutes the building blocks from which the complex multistep mechanisms typical of homogeneous catalysis are built. There has naturally been a great deal of research carried out on ligand exchange mechanisms. However, the majority of this research has been concerned with relatively slow reactions carried out in aqueous solution. Data on rapid ligand exchange reactions in non-aqueous solutions are relatively sparse. Such reactions are in many respects, the more interesting and certainly have greater relevance to the understanding of homogeneous catalysis. In particular, comparative studies of the effect of changes of metal ion, geometry of the complex and ligand substituent are lacking. The present thesis presents the results of such a study.

The group of compounds chosen for study are thiourea and substituted thiourea complexes of cobalt, nickel and zinc. Nuclear magnetic resonance has been used as the principal experimental technique. This technique provides information on both the solution structures of the complexes and the kinetics and mechanisms of the ligand exchange processes.

Two introductory chapters review previous work on ligand substitution and the use of nuclear magnetic resonance to study chemical rate processes. The thiourea ligands chosen can themselves undergo a rate process involving restricted rotation about the C-N bond and a third chapter describes some preliminary experiments designed to clarify the interpretation of the ligand spectra. The cobalt complexes are paramagnetic and tetrahedral in solution. Some replacement of thiourea by solvent occurs and equilibrium constants and thermodynamic data for this process have been obtained. A detailed study of the kinetics of ligand exchange has demonstrated two competing mechanisms. Rates and activation parameters for both processes for a series of complexes have been measured. Changes in both the enthalpies of activation and the entropies of activation are important in determining differences in reaction rate among the substitution reactions.

The nickel complexes exist in solution as equilibrium mixtures of paramagnetic tetrahedral, diamagnetic square-planar and paramagnetic octahedral compounds. These equilibria have been disentangled and the factors determining geometric structure in Ni(II) compounds are discussed. Rate and mechanism data for ligand exchange reactions are presented. An associative mechanism is demonstrated for the tetrahedral and square-planar compounds and a dissociative mechanism for the octahedral complexes. NMR studies of a further series of nickel thiourea complexes containing π-allyl ligands are described. These compounds are known to be catalytically active and the ligand exchange reactions prove to be too fast for measurement with the techniques used.

The zinc complexes are diamagnetic and tetrahedral in solution. The small chemical shifts preclude quantitative kinetic studies but qualitative comparisons with the analogous cobalt and nickel compounds are made. All of the complexes studied are very labile by the usual criteria and the overall study has allowed a more complete discussion of the factors determining ligand exchange rates in such compounds than has hitherto been possible.

An appendix describes some studies of complexes of diacetamide.

abstract: Doctor of Philosophy (PhD)


title: Training-Included Potentiation in the Neocortex and its Interaction with Stimulation-Induced Long-Term Potentiation and Long-Term Depression

contributor:
Racine, Ron
Psychology

subject: Psychology Psychology

abstract: Long-term potentiation (LTP) is a long-lasting increase in synaptic efficacy following high-frequency electrical stimulation. Long-term depression (LTD) is a low-frequency stimulation induced reduction in synaptic efficacy. LTP-inducing stimulation is delivered pre-synaptically through an electrode which has been lowered into a neural pathway in an animal's brain. The stimulation parameters used to induce LTP produce alterations which have many of the same properties as memory. As such, LTP is a popular laboratory model of learning and memory. However, the relationship between LTP and memory remains unclear. The fundamental problem associated with linking the two phenomena is that the experimental paradigms used to study them are fundamentally different. Memory is typically measured behaviorally; LTP is typically assessed by measuring the size of evoked potentials -- an indication of synaptic efficacy. New methods allow the relationship to be more closely examined. The best of these paradigms involves training animals on a atask which requires them to encode information, then monitoring for changes which resemble LTP in the regions of the brain associated with the aquired skill. Collectively this approach is known as behavioral LTP. These paradigms have had limited success, because it is difficult to isolate a memory trace in the brain and rule out confounding variables which may be responsible for any recorded changes. In this thesis a behavioral paradigm is employed which requires animals to reach with one limb to retrieve a food reward. This reaching task paradigm is more effective in dealing with these problems then those used in the past. Because the task is unilateral, the animals can serve as their own controls, eliminating some confounds of previous experiments (such as stress level). The cortical region, which encodes the information necessary to aquire the skill, is relatively circumscrived compared to other tasks and structures. In the current experiments, animals unilaterally trained on the reaching task had larger evoked potentials in the trained hemisphere relative to the untrained hemisphere. Furthermore, subsequent LTP induction was reduced in the trained hemisphere compared to the trained hemisphere. These results are consistent with the hypothesis that LTP and memory have the same underlying mechanism (the training-induced potentiation is believed to "use up" some of the modifiability of the affected synapses). Also consistent with this hypothesis is the finding that either long-term depression LTD- or LTP-inducing stimulation delivered following the acquisition of the task disrupted memory storage. Collectively these data support both the conclusion that memories are stored as synaptic changes and that the reaching task paradigm is a useful tool for investigating the relationship between LTP and memory.

abstract: Doctor of Philosophy (PhD)


title: Oxidation of Orthoxylene in a Transported Bed Reactor

contributor:
Hoffman, T. W.
Chemical Engineering

abstract:
The objective of this research program was to evaluate a gas-solid contacting reactor (called a transported bed reactor) in which the solid catalyst is conveyed upward in a vertical pipe by the gaseous reactants/products; at the top of the reactor the solids are separated from the gas stream and recirculated through the system. The reaction employed in this evaluation was the oxidation of orthoxylene on a vanadia on silica gel catalyst.

This oxidation reaction was studied separately on the same catalyst in a bench-scale fixed bed reactor over a range of temperatures, oxygen and orthoxylene concentrations and flow rates to provide conversions from 1 to 100% and considerable variation in selectivity. Reaction products were analyzed at short on-stream times and after considerable reaction times. These results indicated that reaction rates on freshly oxidized catalyst are much higher than those observed after steady-state has been achieved; selectivity to organic oxidation products is also improved significantly. Reaction studies are also carried out with other catalysts, notably a titania based one, and these results are similar in general behaviour but differ in some important details. Kinetic parameters in the Redox or steady-state adsorption models are evaluated.

This reaction was carried out in a pilot scale transported bed reactor, 3/4 in. O.D. by 27 ft. long. Solid hold-up was measured by activating quick shut-off values. It was demonstrated that stable operation could be achieved at very high solids loadings (solid/gas ratios up to 250 and voidages from 0.60 to 0.86). It is demonstrated that the high reaction rates and selectivities can be exploited in such reactors. Suggestions for further research on such reactor systems are included.

abstract: Doctor of Philosophy (PhD)


title: Perceptual Environment and Development of Cat Visual System

contributor:
Pritchard, R. M.
Psychology

subject: Psychology Psychology

abstract:
Kittens were raised with early visual input restricted to horizontal, vertical, or oblique (45º) lines to determine the oculomotor consequences of such early restriction, and the limits of early neural plasticity.

(i) All animals developed pendular nystagmus (frequency 3-5 Hz) which appeared to be related to active visual search, and was lowest in amplitude for animals exposed to oblique lines.

(ii) Many cats developed convergent squint which was most severe for those exposed to horizontal lines.

(iii) Abnormal binocular functioning of visual cortical units was found in all restricted animals.

(iv) The stimulus orientation of maximum response corresponded to the experienced orientation for most units encountered in the animals exposed to vertical or horizontal lines.

(v) In animals exposed to oblique lines all stimulus orientations appeared to be represented in the cortex; units responding maximally to the experienced orientation were not most often encountered.

The results were discussed in terms of possible anatomical constraints on visual plasticity and a preliminary model of visual development was explored.

abstract: Doctor of Philosophy (PhD)


title: Spin Wave Studies in Antiferromagnets

contributor:
Collins, M. F.
Physics

subject: Physics Physics

abstract:
The thesis investigates three different aspects of spin wave in simple antiferromagnets:

Firstly, the spin wave energies are determined in manganese oxide at low temperatures experimentally using inelastic neutron scattering techniques. This has enabled a determination of the magnetic interactions between the spins.

Secondly, the effects of zero-point motion have been studied theoretically. The particular emphasis is on the way in which the motion affects the spin wave energy, the magnetization and the total energy of the magnetic system. It is found that earlier theoretical treatments, which were restricted to unusually simple cases, can be generalised to encompass a much wider set of conditions.

Finally, a theoretical investigation has been made of the temperature dependence of spin wave energies. Here again, it is found that earlier work restricted to one simple case of an antiferromagnet can be generalised quite extensively. The treatment gives results which predict a different temperature dependence for spin wave of differing wavelengths. Such a dependence is observed experimentally though the theory does not agree quantitatively in all cases.

abstract: Doctor of Philosophy (PhD)


title: A Response Selection Model for Choice Reaction Time

contributor:
Link, S. W.
Psychology

subject: Psychology Psychology

abstract:
The binary choice Fast Guess Model of Ollman and Yellott was generalized to a multiple choice model and six subjects were run in a choice reaction time task to test the model. Stimulus set sizes of two, four and six were used and response accuracy and speed motivation was manipulated through specific instructions which were changed from trial to trial. Three differential motivational instructions were used. In all cases, subjects were to respond with maximum accuracy but were also told on each trial to either disregard the duration of their response, respond within 440 milliseconds or respond within 300 milliseconds.

The generalized Fast Guess Model was rejected because response time parameters of the SCR state were found to change across response accuracy-speed motivation instructions and across stimulus set sizes. Implications of these results for other classes of models were also discussed.

abstract: Doctor of Philosophy (PhD)


title: Letter Identity and Phonemic Processing in Word Comparison: their relative ordering

contributor:
Baron, Jonathan
Psychology

subject: Psychology Psychology

abstract: The view of some is that people process printed words in a highly flexible fashion, attending to now this characteristic of a word, now that, as the task demands it. This thesis, after discussing some models of the types of information in words and the relationships among these types of information and their processing, reports experiments showing three different effects which demonstrate that there are restrictions on the ways in which information about the appearance of letters and their identity is processed relative to information about the phonology or pronunciation of the words. These limitations are explained in terms of a model in which phonemic information becomes available completely at a later time than visual features or the identity of letters in a word. It is argued that the most likely form of this model is one in which visual features and letter-identity become available as a result of the operations of an early processing stage or stages, while phonemic information becomes available as a result of the operation of a subsequent stage, the input of which is the output of the first.

abstract: Doctor of Philosophy (PhD)


title: Ochre Procurement and Distribution on the Central Coast of British Columbia

subject: Anthropology Anthropology

abstract: Ochre is common to archaeological sites around the world and often considered a culturally significant material. It was and continues to be used in a variety of contexts, as pigment for rock art and body paint, medicinally, and as a component of ritual and mortuary practices. However, the nature of its acquisition is poorly understood. This geochemical study uses instrumental neutron activation analysis (INAA) to examine the acquisition and distribution of ochre at and among multiple village sites on the central coast of British Columbia. INAA has shown to be a powerful tool capable of distinguishing different geochemical groups of ochre. Furthermore, the distribution over time and space of these geochemical groups indicates a mode of long-term, highly localized ochre procurement, and the potential for small-scale exchange and shared access to ochre sources. Ochre specimens from Katit (EkSt-1), have geochemically distinct signatures suggesting that the inhabitants of this village primarily accessed one source and did not engage in exchange of ochre with other villages in the region. Ochre specimens from Namu (ElSx-1) and Cockmi (EjSw-1) are from two geochemically distinct sources, which were either accessed by people from both villages, or occur at both sites as a result of small-scale exchange. These patterns of ochre-related behavior are consistent over long periods at each site. In addition to these, a small number of specimens from surrounding camp sites were analyzed to assess the geographical extent of the distribution of ochre sources in the region. These results enable a characterization of the nature and form of ochre procurement and distribution practices, and furthermore, how and what the analysis of ochre can reveal about broader notions of perception of landscape and resource use.


title: Anticancer Natural Products: Evolution and their Biosynthetic Site-Selective Conjugation to Antibodies

contributor:
Magarvey, Nathan
Chemical Biology

rights: An error occurred getting the license - uri.

subject:
natural product
antibody-drug conjugate
cancer

abstract:
Natural products are an important resource for cancer therapy, with highly potent
and diverse anticancer activities. Natural product biosynthesis is well comprehended,
however the evolutionary principles governing the alteration of enzymatic assembly lines
to yield molecules with activity toward distinct various cellular targets are not
understood. This gap in knowledge hinders efforts to synthetically combinatorialize
assembly lines to yield “unnatural” natural products with important or hybrid activity
toward up-regulated targets in cancer. Furthermore, natural products did not evolve in the
context of mammalian systems and would benefit from a delivery mechanism to
cancerous cells to improve their ability to generate successful clinical outcomes.
Consequently, natural products were linked to antibodies targeted to cell surface proteins
up-regulated on cancer cells, generating antibody-drug conjugates (ADC). The
conjugation methodology is problematic by yielding ADCs with varying numbers of
drugs loaded per antibody. This lack of batch-to-batch standardization limits our ability to
completely evaluate the safety profiles and efficacy of ADCs and determine proper
dosages for patients. In this research, light was shed on biosynthetic evolutionary changes
through the study of the antimycin-type family of depsipeptides, specifically
demonstrating that modular insertions or deletions lead to natural product structural
diversification. Additionally, a novel biosynthetic enzymatic method was established to
site-selectively conjugate natural products to antibodies in order to facilitate the
development of more sophisticated cancer therapies.

abstract: Thesis

abstract: Master of Science (MSc)


title: Socio-Economic Status and Community Integration: A Study of Formal and Informal Participation of Urban Migrants

contributor:
Pineo, P.C.
Sociology

subject: Sociology Sociology

abstract:
The focus of this thesis is twofold, the first being theoretical, the second being methodological. Chapter I consists of a review of the migration literature, specifically that relevant to tie relationship between socio-economic status and the migrant's integration into a new community. From this review, a number of hypotheses are generated and subsequently tested employing data from the Migrant Relocation Study. Socio-economic status is postulated to be related to both formal social participation in voluntary associations and informal social participation--both important aspects of integration.

The methodological portion of the thesis consists of the use of a number of methodological techniques, including specifically, index construction, a two wave path analysis and a correction for measurement error, as aids in testing the hypotheses.

Factor analysis, one method of index construction is applied to the informal social participation indicators and points out that categories of social relationships are somewhat more complex than a simple kin, non-kin dichotomy which was used previously in the literature. Instead of grouping all kin together, kin can be more accurately represented by considering it to be at least three separate variables and regarding non-kin, there is reason to distinguish between friends, neighbours and co-workers.

The hypotheses generated by tho review of the literature are tested using the technique of causal modelling. The particular two wave path model used to test the hypotheses is suggested by Heise (1969). It is for application to survey-type data with measurements made on the same variables and the sample at two times. The lagged paths representing the impact of one variable on another during the period between measurements are the basis for causal inference. This model, thus, allows a test of a causal relationship between socio-economic status and social participation.

An important contribution in this thesis is the consideration of measurement error. This thesis attempts to take measurement error into account in solving the path model. Reliability coefficients are calculated for each indicator in the path analysis and the correlation coefficients generated from these are subsequently corrected for attenuation. These corrected coefficients are then used to test the two wave path model.

The results of this thesis are not specifically conclusive. Employing the corrected model support is found for a number of the hypotheses. Results generated from the uncorrected model, however, are somewhat more problematic. Support is found for a causal effect of socio-economic status on formal social participation in voluntary associations and a weak effect in a negative direction of socio-economic status on informal social participation with kin. The analysis also suggests that the causal effect of socio-economic status on informal social participation with friends is in a positive direction and with neighbours is in a negative direction.

abstract: Master of Arts (MA)


title: FUNCTION OF YJEE AND RIBOSOME ASSEMBLY FACTORS

contributor:
Brown, Eric
Biochemistry

subject:
YjeE
Escherichia coli
Chemical Biology
Ribosome biogenesis
cold-shock
Biochemistry
Molecular Biology
Biochemistry

abstract:
Using the model organism Escherichia coli, we discuss herein two novel antimicrobial targets: namely, the protein YjeE and the process of ribosome assembly.

YjeE is essential for viability and widely conserved amongst bacterial pathogens and has no human homologue. We searched for a small molecule probe of the function of YjeE to help circumvent the inadequate genetic tools that are available for studying this protein. Sensitive methods for detecting ligand binding were optimized; however, this effort yielded no inhibitors. A second approach to studying the function of YjeE was the development of a reporter using a promoter that is directly upstream of yjeE in E. coli. The activity of this promoter was tested in the presence of small molecules of known function and in diverse gene deletion backgrounds. YjeE found to be linked to the inhibition of DNA and protein translation as well as central metabolism and respiration. These interactions prompted experiments that revealed YjeE to be dispensable under anaerobic conditions.

Many antibiotics target ribosomal protein synthesis; however, no current antibiotics target the process of ribosome biogenesis. In order to identify new biogenesis factors, the non-essential fraction of the E. coli genome was screened for deletions that gave rise to cold-sensitive growth. We found that genes associated with ribosome function were the most represented cold sensitive factors amongst the genes of known function. We identified and present here two new putative ribosome biogenesis factors, prfC and ychF, which had phenotypes associated with ribosome assembly defects.

abstract: Doctor of Philosophy (PhD)


title: Aboriginal™: Constructing the Aboriginal and Imagineering the Canadian National Brand

contributor:
Giroux, Susan Searls
Chakraborty, Chandrima
Monture, Rick
English and Cultural Studies

subject:
Aboriginal
Indigenous peoples
Tourism
Representation
Globalization
Visual Culture
Native American Studies
Other English Language and Literature
Tourism and Travel
Native American Studies

abstract: The marketing of Indigenous peoples, lands, art and culture from within areas that can loosely be drawn together under the rubric of “tourism,” draws Indigenous peoples in a tenuous and complex web of negotiations of imagery, authenticity, nationalism, economics, and identity. Many scholars have explored the economic implications of such interactions. My dissertation, however, is instead focused on attending to the relationship between the contemporary representation of Indigeneity, Canadian national identity, and the intensifying commoditization of ‘all things Indigenous’ (such as Indigenous bodies, identities, languages, spirituality, and material culture) within such spaces. My work asks, what are the consequences of particular forms of commodification of Indigenous culture and identity? In what ways are Indigenous peoples complicit with such forms and in what ways do we negotiate and/or resist them? How do current representations differ from those during the height of “Wild West” shows during Canada’s early nation- building phase, if at all? Mapping a trajectory of representations and visual spectacle in the latter part of the twentieth and early twenty-first centuries across a number of sites I explore Indigenous and Canadian tourism marketing, the 1976, 1988 and 2010 Olympics, and Casino Rama. Such Indigenous self-conscious representation has often taken up through a constitutive, discursive lens of “Aboriginality.” Since the Canadian state’s entrenchment of the term “Aboriginal” within the Constitution Act (1982), Aboriginality has become its own representational force whereby some Indigenous peoples embrace it as a pathway to community economic revitalization. It is rather more productive, I argue, to recognize the Aboriginal as an allegorical figure of a contemporary market-focused society. While certainly related to what Daniel Francis refers to as the “Imaginary Indian,” the figure of the Aboriginal and of Aboriginality conceals much more sinister state projects that are tied to lingering Canadian state racism and colonializing agendas that seek, through, neoliberal economic terms, to assimilate Indigenous peoples. This assimilationist project is relaunched by the intensification of the corporatization and marketing of culture and identity. Indigenous peoples participation in the production of Aboriginality is increasingly positioned by the state as evidence of a willingness to assimilate but also as evidence of the reconciled nature of relationship between Indigenous and settler Canadians and the indigenization of settler Canadians. I close out by engaging in the fourth chapter a discussion of the artistic expression of Indigenous mixed media artists Rebecca Belmore and Terrance Houle, artists who, I contend, resist the increasingly regimented frame of Aboriginality and challenge the ease with which the state and settlers lay claim to Indigenous imagery, stories, lives, and lands.

abstract: Doctor of Philosophy (PhD)