title: An Experimental Study of the Hydrodynamic Transport of Spherical and Cylindrical Capsules in a Vertical Pipeline

contributor:
Latto, B.
Mechanical Engineering

abstract:
This thesis is concerned with the flow phenomena associated with the hydraulic transport of spherical and cylindrical capsules in a 7.6 cm-diameter vertical pipeline.

In the experiments, spherical capsules of steel, aluminum and nylon of capsule/pipe diameter ratio d/D = 0.57, 0.65 and 0.82 were investigated. Also, right circular cylinders of aluminum and nylon of d/D = 0.49, 0.65, 0.82, and capsule length/diameter ratio L/d = 4, 7, 10, 14 were investigated. The steady-state capsule velocity Vc and the pressure gradient associated with the capsules were measured. Based on the measured results the velocity ratio Rv, the pressure gradient Rp and the unit energy requirements P for the capsules were calculated. The effects of the individual pertinent variables which affect Rv, Rp and P as indicates by the experiments were discussed.

Furthermore, theoretical and semi-empirical correlations between Vc, (ΔP/L)c and the pertinent variables of the systems were derived.

abstract: Master of Engineering (ME)


title: The Effects of Oscillatory Steam Flow on Reflux Condensation Phenomena

contributor:
Round, G.F.
Chang, J.S.
Mechanical Engineering

subject:
Mechanical Engineering
Mechanical Engineering

abstract:
The local and global phenomena in oscillatory steam flow reflux condensation were investigated both experimentally and theoretically.

A series of experiments were carried out in a 4.86m long vertical double-pipe condenser consisting of a 1.735cm diameter inner tube enclosed within a 5cm diameter outer tube. Four different inlet steam flow square-wave modulation frequencies: 0 (steady state), 0.05Hz, o.1Hz, and 0.2Hz, and a constant cooling side inlet temperature and flow rate of 30°C and 1kg/min respectively, were investigated. The experiments covered an average steam flow rate range of 10-300g/min, an amplitude range of 0-150g/min, and flow bias levels of 10-300g/min. These experiments were designed to investigate the effects of frequency, amplitude, and bias (steady component) of the inlet steam flow modulation on the observed process.

Five different operating modes were identified in the condenser as the inlet mass flow rate was increased. The operating modes, categorized according to the observed flow regimes in the condenser, were: (1) reflux condensation without water column mode, (2) reflux condensation with water column mode, (3) first carry-over mode, (4) second carry over mode, (5) climbing film flow mode. Complete reflux condensation was maintained only in the first two modes of operation.

Under steady inlet steam flow conditions, it was found that the flooding in the tube caused the system to undergo transition from the first mode of operation to the third mode of operation at very low inlet steam flow rates, thereby severely limiting the condensation capacity in complete reflux condensation. Under modulated steam flow conditions, and depending on the particular combination of frequency, amplitude, and steam flow bias, as much as 300% improvement on the condensation capacity was obtained. In general, improvement in the condensation capacity was favored by low frequency, high amplitude, and low to moderate steam flow bias levels.

Observations of the experimental phenomenon showed that once flooding occurred in the tube under steady inlet steam flow conditions, the resulting net upward condensate flow led to the formation and build-up of single-phase condensate (water column) on top of the condensing region. The back pressure exerted by this water column on the condensing region upstream led to a huge increase in the operating pressure and overall pressure drop across the condenser tube, which was directly reflected in the measured operating pressure. Experimental results showed that substantial reductions in the time-averaged system pressure and pressure drop across the condenser were achieved under modulated steam flow conditions, due to the tendency of the oscillations in the steam flow to destabilize the water column or prevent sustained water column formation and growth. Under modulated steam flow, the system pressure was influenced mostly by the frequency of modulation and the steam flow bias, and to a lesser extent the amplitude of steam flow. These factors were found to play dual roles in the time-averaged overall pressure drop, as this pressure drop was found to play dual roles in the time-averaged pressure drop increased with both the frequency of modulation and the flow bias. Additionally the experimental results showed that in addition to the remarkable reductions in the overall pressure drop achieved with steam flow modulation, the relative amplitude in the system pressure introduced by flow oscillation was unexpectedly very small (the maximum value obtained in the present experiments was less than 4%).

Experimental results of local wall heat fluxes showed that a significant part of the heat transfer augmentation achieved with steam modulation was due to condensate entrainment from the film, and more importantly from the water column where it existed. Estimates of water column entrainment rates made from experimental results revealed that extremely high entrainment ratios could be attained, depending on the amplitude of modulation. The high entrainment rates were manifested in the increased heat transfer rates around the water column region, due to the direct contact heat transfer made available by the interaction of the steam with the much colder water column. However, the local heat transfer under modulated steam flow conditions exhibited significant cyclic components, the magnitude of which depended on the minimum condensing region length (which was set by the steam flow bias and the amplitude in the inlet steam flow.

A fully implicit seven-equation two-fluid model was specifically formulated to model the reflux condensation process as observed in the present experiments. The model was solved by employing a simple time-dependant dynamic grid adaptation technique designed to track the unknown and time-varying condensing region length. A set of empirical correlations for interfacial mass, momentum, and energy transfer selected from the literature and developed from the present experimental results were employed in the solution of the two-fluid model. The model was used to investigate the effect of the tube diameter, tube length, and cooling side flow rate and inlet temperature on the process.

Numerical simulations of some of the present experiments, in the reflux condensation mode of operation, were carried out using the two-fluid model, but the model exhibited convergence problems in the presence of a water column, and so experiments in the second mode of operation could not be simulated with a reasonable degree of accuracy.

Theoretical results obtained from the model showed that as the tube diameter increased the pressure drop per unit length of condenser decreased, and the inlet steam flow rate at flooding increased, or equivalently the condensation capacity or operating range of the condenser increased, With respect to the inlet cooling water temperature, the model results showed that the heat removal rates in the condenser increased as this temperature was decreased.

abstract: Doctor of Philosophy (PhD)


title: Characterization and Explanation of Primary, Return and Onward Interprovincial Migration: Canada, 1976-86

contributor:
Liaw, K.L.
Geography

subject: Geography Geography

abstract:
Using data from the Public Use Sample files of the 1981 and 1986 Canadian censuses, this thesis sets out to characterize and explain primary (migration from the province of birth), return (migration back to the province of birth following an initial migration) and onward (migration to a province other than the province of birth following an initial migration) interprovincial migration within Canada for the 1976-81 and 1981-86 periods.

Three major themes are developed and expanded over the course of the thesis. The first theme is one of characterization. In order to study the propensities of in- and outmigration, appropriate in- and outmigration rates are computed (Long, 1988; Rogers and Belanger, 1990). The major finding is that the Canadian migration patterns are similar to those observed in the United States.

The second theme is the explanation of return and onward migration amongst non-natives (those whose province of residence was different from their province of birth) aged 22-44 within Canada by applying a three-level nested logit model to the 1976-81 micro data. Research has tended to take either a macro-adjustment or micro-behavioral stance in modeling migration flows, but the complementary frameworks suggest the need for an integrative approach incorporating structural-institutional forces and personal factors. Important factors include mother tongue, level of education, age and family type. Influential provincial attributes include economic variables, distance and cultural similarity. The main finding is that return migrants also responded to interprovincial variations in economic opportunities in a rational way.

The final theme is the temporal analysis of primary, return and onward migration through the economic boom of 1976-81 and economic bust of 1981-86. Relative to return migration, primary and onward migration became less important during the period of economic bust, although migration became less important during the period of economic bust, although migration selectively with respect to personal factors remained basically the same. In making migration decisions, non-natives continued to respond to the spatial variation in economic opportunities so that the spatial patterns of migration changed in response to the changing spatial economy.

abstract: Doctor of Philosophy (PhD)


title: Community Participation in Research and Development: A Case Study from Pangnirtung, Northwest Territories

contributor:
Warry, Wayne
Anthropology

subject: Anthropology Anthropology

abstract:
Theories and models of community participation have received considerable attention from academics in the social sciences, and from practitioners in developing countries. This thesis examines the participatory paradigm as it is manifested in two realms: economic development and applied anthropological research. Primary data are drawn from field-research in the Inuit community of Pangnirtung, Northwest Territories.

This thesis is unique in its presentation of a public evaluation, co-researched together with an Inuk member of the community. This report is used as a case-study that provides fodder for the theoretical and pragmatic discussions that surround it. Weaving together academic and applied concerns, this dissertation performs a dual purpose. The first objective is to critically examine the ideas that lie at the root of the participatory research and development ideology, and through the identification of knowledge as power.

The second goal is to offer insight into the political, economic, and cultural pragmatics of doing participatory research and development at the community-level. The evaluation of community-based tourism development in Pangnirtung provides the ethnographic data on which this more applied analysis is based. The participatory methodology employed in the evaluation is the base of discussion about the strengths and weaknesses of this type of research. This thesis offers the "co-researcher" model of investigation as a productive process that is relevant not only to the researchers, but also to the communities which are the subject of research.

The conclusion draws several theoretical and ethnographic parallels in doing participatory research and development in the North. Important policy implications are highlighted both for government and development practitioners, and for leaders engaged in the struggle for aboriginal self-government. Finally, several recommendations are made toward developing methodologies of research and development, more appropriate to aboriginal community contexts.

abstract: Doctor of Philosophy (PhD)


title: Model Structure and Adjustable Parameter Selection for Operations Optimization

contributor:
Marlin, T.E.
Chemical Engineering

subject:
Chemical Engineering
Chemical Engineering

abstract:
The value of model-based process optimization systems for competitive advantage in many industries, has been widely recognized. Such model-based optimization systems include Real-Time Optimization, On-Line Optimizing Control, off-line process scheduling, and any other economic process optimization scheme which uses a process model to predict optimal plant operation. The thesis investigates the design of these model-based optimization systems, particularly with respect to model structure and adjustable parameter selection.

The main contribution of this work include design phase methods, based on fundamental principles of optimization and statistics theory, for determining whether a model-based optimization system can attain the plant optimum, as well as methods for discriminating between design alternatives. Three necessary conditions for zero-offset from the optimal plant operation are presented. These include Pont-Wise Model Adequacy, Augmented Model Adequacy and Point-Wise Stability. Recognizing that achieving zero-offset from the plant optimum may not always be possible, or may not be the only design objective, a Design Cost method is presented for selecting among design alternatives. This Design Cost method provides a natural "trade off" between offset elimination and variance of the predicted optimal manipulated variable values.

Finally, the thesis is completed with a larger-scale case study involving the Williams-Otto Plant [1960]. In the case study selection of a process model and the adjustable parameter set for implementation in closed-loop Real-Time Optimization system is investigated.

abstract: Doctor of Philosophy (PhD)


title: Compliance with Chronic Dietary Regimens: Measurement, Prediction, and Outcome

contributor:
Campbell, Dugal
Psychology

subject: Psychology Psychology

abstract: Compliance has been defined as "...the extent to which a person's behavior coincides with medical or health advice" (Haynes, 1978, pp. 1-2) and is an important area of research in behavioral medicine. There are several key issues involved in compliance research. Specifically these are: 1) How do we define and measure compliance?; 2) how can we predict compliance?; and 3) does compliance lead to a better outcome than does noncompliance? This dissertation focuses on the question of what does psychology have to contribute to our understanding of these issues? The first study investigated the amount of agreement between the various definitions of dietary compliance in patients on hemodialysis. It demonstrated that one reason why there is so little agreement on the factors that predict compliance is that researchers in this area define compliance in very different ways. The second study explored the possibility of using outcome to provide an objective definition of compliance. It was found that dietary compliance is not related to outcome for hemodialysis patients. The third study focused on the use of self-efficacy to predict compliance in patients with Type 2 diabetes mellitus, a condition where dietary compliance may be easily measured. The results suggested that gender differences influenced the predictive power of self-efficacy. The interaction between gender and self-efficacy was confirmed in a laboratory task as well. Much of the experimental research on dieting and weight regulation ignores the potential impact of gender differences. The results of these studies suggest other paths for future research and also demonstrate that psychology can make a valuable contribution to research on compliance with chronic dietary regimens.

abstract: Doctor of Philosophy (PhD)


title: The Effects of the Technique and the Technology of Communication Upon Religious Thought and Religious Organization in the West as Elucidated and Suggested by the Works of Harold Innis

contributor:
Grant, G.P.
Religion

subject: Religion Religion

abstract:
Harold Innis remains, some twenty-two years after his death, the paramount scholar on the subject of the effects of communication in the history of the West. This thesis is the first attempt to deal comprehensively with his works from the perspective of what they say about religion. The approach taken is to examine what he says and to elucidate its significance for an understanding of religion. The thesis supported in this work is that, on the basis of Innis' works, religion in the West may be viewed, at least in part, as an effect of communication.

Innis' works suggest that religion, in an organizational sense, is a monopoly of knowledge or a monopoly of truths with a bias either to time or to space. The bias is an effect of the dominant medium of mechanized communication. However, his works also identify a fundamental religious experience, outside any organizational or institutional setting, which is an effect of oral communication. This is a spiritual creativity which implies individual freedom and the pursuit of truth.

Mechanized communication is seen to convert the pursuit of truth into the maintenance and defence of truths on a large scale and the resulting monopolies of knowledge or systems of "religious" truths provide for the efficient control of man over either time or space.

Innis' works emphasize the value of questioning all "religious" truths. Since they are the basis of large scale control all must be continually questioned in order for man to be free. His works suggest that they must also be questioned in order for man to be truly religious. A central message in his works is that an agnostic state of mind is indispensable for individual freedom and spiritual creativity. This state of mind is an effect of oral communication and it may be seen to be of the essence of religion.

Innis' works point out that no means of mechanized communication adequately or fully communicates the oral tradition. Each technique and technology imposes a message of its own. This suggests that the message of the Christian gospels, for example, which came out of an oral milieu, will be changed when communicated in mechanized forms. It will be different from and less than the original. An understanding of the effects of communication is therefore important for an understanding of the gospel message. Innis' later works help to provide such an understanding.

They emphasize that the message always reflects the means and the medium of communication. Man's thinking is biased by the way he communicates. Therefore, he may never know in any absolute sense what truth is. He may, however, have faith that truth is. This brings an important new perspective to the understanding of religion.

This thesis identifies early and later stages in Innis' work but it concentrates on the later stage. A brief synthesis of his early works is included at the beginning in order to provide a better understanding of his theory of effects and monopolies. The main body of the thesis synthesizes Innis' writings on the effects of communication and explains their significance for an understanding of religion in the West. An Appendix helps to explain further the somewhat different perspective to Innis' works taken in this thesis and the significance of this perspective for the study of religion.

abstract: Doctor of Philosophy (PhD)


title: Social Economy of a Northwest Coast Plank House

contributor:
Cannon, Aubrey
Anthropology

subject:
Anthropology
Social and Behavioral Sciences
archaeology

abstract: The Dionisio Point site on Galiano Island, British Columbia has been the focus of previous research directed by Dr Colin Grier. This thesis builds upon Grier's excavation and analysis of House 2 at the site through a consideration of animal bone remains. These data are examined at several scales, beginning at the level of excavation units and moving toward a discussion of regional settlement patterns. Temporal trends in fauna within House 2 are visible at only a very fine level of analytical resolution. The nuanced nature of these changes suggests minimal variation in subsistence practice during the use of Dionisio Point. The diversity and scale of such activities are reduced following the abandonment of House 2, although their overall orientation remains very similar. When house inhabitation layers are combined, spatial patterning in faunal remains within the house is likewise observable only through fine-grained analysis. The absence of obvious patterns in the distribution of these spatial data is striking. This suggests that use of House 2 by its inhabitants was more contextual and subtly variable than originally proposed. Multiple lines of archaeological evidence indicate that the house was inhabited during the spring and summer and that Dionisio Point was likely the location of seasonal group aggregation. During the spring and summer months, family groups appear to have arrived at the site according to their individual seasonal routines. At times House 2 itself was inhabited by fewer groups than during the peak of summer aggregation. These yearly movements through the southern Strait of Georgia landscape encompassed a diverse range of activities and preferences. Archaeological evidence from fourteen further Strait of Georgia shell midden sites supports a significant degree of variation in site use. The indication is that social relationships were equally variable across a dialectical continuum of human interaction.

abstract: Master of Arts (MA)


title: Diffusional Growth of Oxide Scales on Cobalt-Iron Alloys

contributor:
Smeltzer, W.W.
Metallurgy and Materials Science

subject:
Materials Science and Engineering
Metallurgy
Materials Science and Engineering

abstract: In this thesis the results of an experimental investigation and theoretical analysis of high temperature oxidation properties of cobalt-iron alloys are presented. Cobalt-iron alloys containing up to 70% iron were subjected to pure oxygen atmospheres with pressures ranging from 10ˉ⁴ to 1 atm at 1200°C. The reaction kinetics, oxide scale morphologies and spatial distributions of the reacting species in the oxidized specimens were determined. It has been established that the reaction is controlled by metal diffusion through the oxide scales separating the reactants. A ternary diffusion model was invoked to describe the high temperature oxidation behaviour of the investigated alloys. The consistency of the model is tested by evaluating the concentration profiles from metal diffusion coefficients and nonstoichiometry of ternary oxides using the Wagner phenomenological equations. The comparison of the results from theoretical calculation suggests that the theoretical analysis adapted in this work is consistent with the actual physical and chemical processes governing the oxidation reaction.

abstract: Doctor of Philosophy (PhD)


title: HELICAL MILLING: AN ENABLING TECHNOLOGY FOR MACHINING HOLES IN FULLY HARDENED AISI D2 TOOL STEEL

contributor:
Koshy, Philip
Mechanical Engineering

abstract:
The machining of hardened steel is becoming widespread throughout the manufacturing industry owing to the benefits derived in the form of manufacturing flexibility, better product quality, and the prospect of dry machining. This coupled with developments in super hard cutting tool materials and machine tools, and better understanding of hard machining technology translates into significant economical benefits and faster turnaround times.

The majority of applications involving hardened steels comprising AISI D2 tool steel relates to the manufacturing of die and mold wherein the current trend of hard machining is restricted by the limitations imposed by hard drilling. Being the final operation in many manufacturing applications, it is imperative that the process of drilling be robust and reliable to enhance the value already added to the product. Problems associated with inherent deficiencies in the drilling process kinematics, combined with poor machinability of hardened D2 tool steels due to the presence of hard and abrasive carbide particles in its microstructure that lead to catastrophic drill failure, constitute the single major process chain bottleneck in realizing hard part manufacture.

The research work presented in this thesis focuses on the application of helical milling as an enabling technology for hole making in hardened AISI D2 tool steel in comparison to conventional drilling, which is not feasible at the current level of developments in drilling technology. Helical milling employs a rotating end mill of a diameter smaller than the hole, and traverses a helical path to generate a hole. The novel process derived by simple modification of tooling and process kinematics offers an excellent avenue to successful machining of precision holes in hardened D2 tool steel.

In order to compare the performance of helical milling against drilling, four types of conventional twist drills intended for drilling hardened steels were employed in the machining experiments while, end mills commonly used in the die and mold industry, were chosen for helical milling. The processes were evaluated in terms of tool life, wear progression, wear mode, cutting forces and hole quality.

Accelerated wear followed by catastrophic fracture of the cutting edges at the periphery of the drill was observed to be the primary tool failure mode in conventional drilling as opposed to uniform progressive flank wear in helical milling. The innovative helical milling method is found to facilitate1 hole-making in hardened D2 tool steel with an order of magnitude improvement in tool life. The helical trajectory of the tool in helical milling facilitates material removal near and at the center of the hole by cutting rather than extrusion as seen in drilling, thereby reducing the excessive thrust forces that cause work material breakouts at the hole exit in conventional drilling.

Furthermore, chip evacuation in not problematic in helical milling considering that chips can be removed across the radial clearance between the tool and the hole as opposed to through the flute space in conventional drilling. This implies that an air blow could be employed to assist chip transport in helical milling facilitating dry machining, considering that in many drilling applications cutting fluid is merely used to flush the chips away from the cutting zone. The intermittent cutting action in helical milling further provides respite to the cutting edge from the imposed mechan ical and thermal loads and offers exceptional chip control. The process represents an enabling technology with additional benefits of superior hole quality thus rendering the elimination of an additional reaming process.

abstract: Master of Applied Science (MASc)


title: Residential Mobility of Italian Immigrants in Hamilton

contributor:
Gentilcore, R.L.
Geography

subject: Geography Geography

abstract:
The purpose of the thesis was to look at the spatial characteristics and factors affecting residential mobility of a group of first generation Italian immigrants in Hamilton. It also investigated the link between occupational and residential mobility. Data for this study were collected in two phases: questionnaires were mailed out to a randomly selected sample of Italians in the city and a subgroup of the respondents were interviewed orally.

It was found that the immigrants upon arrival settled in the older parts of the city generally north of Main Street, between Queen and Ottawa Streets. This section, close to the industrial sector, has all the characteristics of an immigrant receiving area. The group was highly mobile. Some moved within the area of original settlement but with an eastward shift in relocation. Others moved to different parts of the city, chiefly the East and the Mountain. This latter movement signifies a move to newer housing, but where a considerable number of Italians are to be found.

While number of job changes and occupational mobility were significant in affecting number of moves, only occupational mobility affected the type of move made. It was interesting to note that, contrary to what was expected, those who moved within the area of original settlement were occupationally more mobile than those who moved out of it. No discernable pattern was found in the relationship between residential and occupational mobility. In some case one took place before the other and in others, they occurred around the same time.

From the oral interviews it became clear that the reasons for moving were different from those hypothesized. As boarders they were looking for cheaper places. As owners they were looking for more space, bigger houses, better neighbourhoods, opportunity to buy a lot and build their own houses. Their idea of prestige is not in the kind of job, but in the type of house they own and where they live. All in all, the immigrants show a great deal of solidarity be it social or localised.

abstract: Master of Arts (MA)


title: WAR AND THE HOME FRONT: DEVON IN THE FIRST WORLD WAR, 1914-1918

contributor:
Heathorn, Stephen
Horn, Martin
History

subject: History History

abstract: This investigation contributes to the existing scholarship on Britain and the First World War by examining the war's impact on the county of Devon in southwest England. More specifically, this study pays particular attention to how communities, families, and individuals responded to the pressures of war and to what extent social unity was achieved at the county level. By exploring the relationship between the state and its citizens, this dissertation questions the extent to which Devonians were passive and accepting of the sacrifices and hardships that the government required from them, how their experiences were informed, and to what extent class, gender, and religious differences limited public support for the war? While this dissertation argues that Devonians were generally supportive of British participation in the war, that support was provisional and based on the perception of 'equality of sacrifice' - the expectation that the burdens of war would be shared equally throughout the county and across all segments of society. This study reveals that the inequalities of sacrifice and inconsistencies of government policies burdened some groups more than others and led to social disaffection. Rather than promoting solidarity, the war often exacerbated rural/urban tensions, highlighted the social and economic divisions that characterized relations between the communities of northern and southern Devon, and led to frequent and public criticisms of the government's management of the war.

abstract: Doctor of Philosophy (PhD)


title: Faith, Language, and the Problem of Evil

contributor:
Weeks, I.G.
Religious Studies

subject: Religion Religion

abstract:
The problem of evil is meant to show that the propositions (A) "God exists and is all-good and omnipotent," and (B) "There is evil in the world," are logically inconsistent and incompatible. Formulated in this way, the problem of evil confronts theism with the following dilemma. If, on the one hand, it can be shown that propositions (A) and (B) are logically incompatible, therein lies a proof of atheism and the end of theism as a rational enterprise. If, on the other hand, propositions (A) and (B) are not logically incompatible, then religious and theological utterances become, on the basis of Antony Flew's falsification challenge, vacuous and meaningless, and are, at best, pseudo-assertions.

The purpose of this study is to attempt to resolve the above-mentioned dilemma by attacking both horns; that is, by showing that both alternatives are in fact false. It is argued that propositions (A) and (B) are not logically incompatible and that, although (B) does not falsify or count against (A), religious language is nonetheless meaningful. In order to substantiate this latter claim, a careful study of the concept "meaning" is made to show why the falsification criterion of meaningfulness is not the only criterion of meaningfulness, but that the actual use of any language provides a sound criterion.

In substantiating the former claim, a careful examination of the nature and use of such concepts as "omnipotence", "omniscience", "all-goodness", and "freedom" is made' in order to compare them as they appear in the formulation of tho problem of evil with their traditional usages. Next, the whole question of Divine Omnipotence, Omniscience and Foreknowledge, Divine Goodness and Human Freedom is discussed to show that the traditional free Will Defence is valid in that it shows that not even an omnipotent God could make men such that they would always choose freely what is right. The notion of a perfect world, a world free of evil, suffering and defect, is next discussed. It is argued that a world free of evil and defect is logically impossible, and further that even if such a world were possible, human life insofar as it involves moral developments and rationality would not be possible.

The discussion ends with a consideration of the attitude of the religious believer when faced with evil and suffering in the world. It is my contention that, although religious people are affected by the great deal of pain; evil and suffering in the world, their faith is not threatened; that is, they need not (and do not) give up their belief in a God of love. This does not mean that evil and suffering do not affect the believer, that he is not concerned about them, for clearly he is. He is constantly struggling with suffering and evil, all the time trying to understand why these must be. He may never understand why evil and suffering must be, but he does not relinquish his belief in God because he knows that evil will be overcome. Others (nonreligious people) may never understand his attitude, but that is only because they do not share his beliefs. And it is here that the whole issue between the believer and the non-believer reaches (it seems) an unresolvable deadlock.

abstract: Doctor of Philosophy (PhD)


title: The Problems of the Subnormal Family

contributor:
McCrimmon, A.L.
Sociology

subject:
Social and Behavioral Sciences
Sociology

abstract: Master of Arts (MA)


title: Role of Modified Nucleosides in Transfer RNA

contributor:
Ghosh, H.P.
Biochemistry

subject: Biochemistry Biochemistry

abstract:
Transfer ribonucleic acids are indispensable components of cellular protein synthesising systems. Besides the four major nucleosides namely, uridine, cytidine, adenosine and guanosine, tRNA molecules contain a number of modified nucleosides. An attempt is made in this thesis to investigate the functional roles of two such modified nucleosides present in tRNAs from baker's yeast.

Two species of lysine accepting tRNA and one species of each of isoleucine, threonine, arginine and asparagine accepting tRNAs were purified from baker yeast. All of these tRNAs recognised codons starting with adenosine. A fast and sensitive method using high pressure cation exchange chromatography, was developed for analysis of the modified nucleosides present in these tRNAs. The modified nucleoside, N-[9(β-D-ribofuranosyl)purin-6-vlcarbamoyl] threonine (t⁶A) was present in each of the above mentioned species of tRNA. The data provided further support to the generalisation that all tRNAs recognising cations starting with the adenosine contained t⁶A.

Another modified nucleoside 2-thio-5-carboxymethyluridine (U*) was present only in one species of lysine tRNA (tRNA₂^(Lys). U* was known to be present at the 5' end of the anticodon in a few tRNAs which only recognised codon XYA. The coding properties of tRNA₁^(Lys) and tRNA₂^(Lys) were studied to investigate the role or U* in tRNA₂^(Lys). Further studies in this line were performed by chemically modifying U* in tRNA₂^(Lys) and observing its effect on the coding properties of tRNA₂^(Lys). These studies revealed that U* not only influenced the coding properties of tRNA₂^(Lys) but also was important in maintaining the efficiency of tRNA₂^(Lys) in the process of in vitro protein synthesis.

abstract: Doctor of Philosophy (PhD)


title: The Role of Axoplasmic Transport in Collateral Sprouting

contributor:
Diamond, J.
Neurosciences

subject: Neurosciences Neurosciences

abstract: In the present research a comparison has been made of the effects of blockade of axoplasmic transport in a nerve to the hind limb of a salamander, with those of sectioning the nerve; the particular focus of attention was the peripheral fields of adjacent nerves to the same limb. The normal touch-receptive and motor fields of the spinal segmental nerves 15, 16 and 17, which innervate the hind limb, were found to be, bilaterally symmetrical. Both after section of nerve 16, or after acute treatment of it with colchicine, a drug which blocks axoplasmic transport, the adjacent nerves 15 and 17 significantly increased (P < 0.05) the size of their touch-receptive fields; increases in motor field were statistically significant only after partial denervation. However, colchicine treatment produced a blockade of the fast axoplasmic transport of catecholamines and cholinesterase, as shown by histochemical methods; presumably the axonal transport of other substances was also blocked. The colchicine also significantly reduced the number of microtubules in the treated axons. Taken as a whole, these findings are consistent with the concept that the size of peripheral nerve fields may be regulated by trophic factors which are continually supplied to the target tissues by fast axoplasmic transport. It is the reduction in the supply of these factors along sectioned nerves which is responsible for the collateral sprouting of adjacent nerves.

abstract: Doctor of Philosophy (PhD)


title: Are Estrogens Neuromodulators?

contributor:
Diamond, J.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
Ovulation is the result of the positive feedback action of estrogen, either alone or in combination with progesterone, and the integrated sensory input from the external environment onto the neural circuits controlling gonadotrophin secretion. During the dioestrus II in the 4-day cycling rat the ovaries secrete an increasing quantity of estrogen which stimulates neurons in the preoptic area (POA) to trigger the surge of luteinizing hormone releasing hormone into the capillaries of the hypophysical portal plexus. However, the mechanisms whereby estrogen stimulates this increased activity are, as yet, unknown.

The binding of estrogen to specific target areas within the brain may induce changes in the metabolic function of neurons or it may directly or indirectly affect the electrical properties of neuronal membranes. The latter possibility has been tested by observing the affects of an intravenous (i.v.) injection of estrogen on the spontaneous activity and responsiveness to iontonphoretically applied putative neurotransmitters of identified preoptic neurons.

Experiments I and II were undertaken in order to establish certain parameters of the experimental design. Experiment I demonstrated that halothone anaesthesia inhibits ovulation in the cycling rat by an action on the neuroendocrine circuits which control gonadotrophin secretion. In experiment II measurements were made of the plasma concentration of estrogen following various doses of an i.v. injection of estrogen or progesterone would stimulate an increased secretion of LH in estrogen primed ovariectomized rats. Measurements of serum LH concentrations one and five hours after the injection showed there was no stimulation of LH under these conditions.

Experiment III was undertaken to identify neurons in the POA which are thought to implicated in a neuroendocrine circuit controlling gonadotrophin secretion and which may be target neurons for the positive feedback action of estrogen. Cells in the POA, which receive an input from the stria terminals have been identified by stimulating this pathway at its point of convergence in the amygdala. Antidromic stimulation techniques were employed to identify cells in the POA which make a direct connection with the basal hypothalamus.

Experiment IV constitutes the major objective of the research, which was to thought to be implicated in a neuroendocrine circuit controlling gonadotrophin secretion and which may be target neurons for the positive feedback action of estrogen. Cells in the POA which receive an input from the stria terminalis have been identified by stimulating this pathway at its point of convergence in the amygdala. Antidromic stimulation techniques were employed to identify cells in the POA which make a direct connection with the basal hypothalamus.

Experiment IV constitutes the major objective of the research, which was to investigate 1) the sensitivity of antidromically identified preoptic neurons to iontophoretically applied putative neurotransmitters; the cells were inhibited by both the cataecholamines, dopamine (DA) and norepinephrine (NE) but were unresponsive to acetylcholine applied iontophoretically; b) to test the possible membrane effects of estrogen on those antidromically identified cells. Two indices of a change of the excitability of preoptic neurons were used (i) the effects of an i.v. injection of estrogen on the rate of spontaneous activity and (ii) changes in the response of a neuron to electrophoretically applied DA or NE following the injection of estrogen or progesterone in primed and unprimed animals. The results of the first series of experiments demonstrated that estrogen can decrease the rate of spontaneous activity in identified preoptic units. Some cells showed a long lasting depression in their spontaneous activity following the steriod injection while others showed a short term decrease in the rate of unit discharge five minutes after estrogen administration. In the second series of experiments no changes were observed in the dose response curves of iontophoretically applied DA or NE thirty minutes after the steroid injection in either group of animals. The negative finding could be due to the technical limitations of this type of experiment or to the fact that estrogens do not affect the response of neurons to synaptic inputs in which these amines may function as neural transmitters.

abstract: Doctor of Philosophy (PhD)


title: The Christian Ethics of Norman Thomas, Socialist

contributor:
Greenspan, Louis I.
Religious Sciences

subject: Religion Religion

abstract: As a case study in Christian ethics, this thesis is an investigation of Norman Thomas' Christian social ethics, its background, its explicit presentation, and its continuing importance after Thomas abandoned other aspects of Christianity. The study focuses primarily on the values and ethical principles expressed in Thomas' social philosophy, during his year as Presbyterian minister and later as Socialist Part leader. This examination of his social thought is presented by a consideration of the social ethics of the Protestant Social Gospel tradition and the entire study concludes with relections on Thomas place in the history of Christian social ethics. The study makes it abunduntly clear that Norman Thomas, as a Christian minister, was part of the Protestant Social Gospel tradition that sought to establish the Kingdom of God on earth in America and that, by the twentieth century, had come to see that the Kingdom as characterized by peace, socialism, and individual freedom. Even more important, the analysis of Thomas' later social philosophy reveals that he continued throughout his later life to adhere to the same social goals and ethical principles that had been at the heart of his understanding of Christianity. With the rejection of his earlier notion of a God who intervenes on the side of right, Thomas was no longer so able to take absolute stands, but the entire approach of his political work remained ethical and the values were the very same ones that had characterized his Christian days. While it has been widely though that Thomas' mature social philosophy reflected some of his earlier Christian ethical principles in his socialism has not been examined prior to this thesis. Norman Thomas' social ethics was considerably closer in character to the social ethics of perennial Christian theology (for example, Thomas Aquinas) than to that of orthodox Protestantism. This is the conclusion reached in relating Thomas' thought to other forms of Christian social ethics; it may shed some light on the likelihood of persons from particular traditions finding Thomas' socialism compatible with their theological views.

abstract: Doctor of Philosophy (PhD)


title: Determination of Longwave Irradiance at the Ground

contributor:
Davies, John A.
Geography

subject: Geography Geography

abstract: Incoming longwave irradiance at the earth's surface under cloudless or near cloudless skies was determined by three instrumental methods. The most reasonable results were obtained using a Eppley pyrgeometer fitted with a silicon dome. Problems associated with an Eppley pyrgeometer equipped with a KRS-5 dome and with a Funk-type Swissteco pyrradiometer are demonstrated. Measured irradiances were compared with those calculated from various physical and empirical models under a variety of atmospheric conditions. The former usually agreed with measured irradiance to within 15%. The latter showed variable agreement. The Swinbank model with only one dependent variable provided as good an estimate as the more complex physical modes. The role of aerosol at infrared wavelengths is examined and is shown to have minimal effect on the longwave flux at the ground.

abstract: Master of Science (MS)


title: Metal and oxygen activities in the Fe-Ni-O and Ni-Cr-O systems between 900°C and 1100°C

contributor:
Smeltzer, W. W.
Metallurgy and Materials Science

abstract:
This thesis concerned with the experimental determinations of the thermodynamic parameters describing the Fe-Ni-O and Ni-Cr-O ternaries between 900°C and 1100°C.

Equilibrium oxygen pressures for Fe-Ni and Ni-Cr allows equilibrated with their oxides have been measured by an electrochemical cell with a calcia stabilised zirconia electrolyte. These pressures were related to compositional determinations of the solid phases, using an electron probe microanalyser, and correlated with the ternary isotherms. Both the Fe-Ni-O and Ni-Cr-O systems have been described by equilibrium oxygen pressure diagrams which relate oxyren activity to the compositions of the equilibrated phases.

The variation of metal activities with alloy composition for Fe-Ni and Ni-Cr alloys has been determined between 900°C and 1100°C. Spinel-alloy equilibria in the Fe-Ni-O system have been described by a Gibba-Duhem calculation and by a structural model for the spinel based on a lattice point defect model.

Experimental observations of the scales formed on Fe-Ni-Cr alloys are qualitatively discussed with respect to thermodynamic considerations.

abstract: Doctor of Philosophy (PhD)


title: Experimental Murine Teratomas

contributor:
Carr, D.H.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
Early in the development of the embryo, cells lose their ability to differentiate into any adult type of cell and become determined. A cell which has achieved a certain degree of differentiation can ultimately reproduce to form only a limited number of cell types along the original line of differentiation: for example, a primitive mesenchymal cell can give rise to only connective tissues such as muscle or bone.

Apart from the primordial germ cells (those cells which later give rise to oocytes in the female and spermatocytes in the male), all cells have begun to specialize, with a consequent narrowing of their potential, very early in gestation.

Teratomas are neoplasms which contain many kinds of tissues which are foreign to the organ in which they arise. There is controversy over whether these tumours arise from the growth of cells which have escaped early developmental controls, or whether they arise from the proliferation of the only multipotential cell in the body, the germ cell. Rather than following their normal path of differentiation to oocytes or spermatocytes, they might fulfil their potential to form almost any kind of tissue. Thus tumours composed of skin, bone, muscle, nervous tissue, and glands are found in adult testes and ovaries.

Since the germ cells arise in the embryonic yolk sac and travel up the umbilical cord to the developing gonads, there is a theory that these multipotential cells may occasionally become lost and much later, often in adulthood, begin their proliferation in sites along the midline: at the base of the spine, in the chest and throat.

The experiments in this thesis explore an animal model in which teratomas can be produced by the grafting of 7½-day mouse embryos to the gonads of adult hosts. According to the literature the tumour which develops as a result of this operation is identical to those arising spontaneously in a highly inbred strain of mouse. Those experimental tumours which contain areas of undifferentiated tissues can be transplanted to other hosts; sometimes retaining their embryonic nature for many generations.

Whole embryos develop as teratomas in up to 80% of grafts to male hosts. The embryos can be cut in such a way that one half contains extra-embryonic material (that which eventually forms the placenta) and also the yolk sac containing the germ cells, and the other half which contains only sonatic tissue.

Grafts of the somatic parts result in teratomas in 74% of the testes, a rate similar to tumours from whole embryos, whereas grafts of the extra-embryonic parts containing germ cells resulted in only 1 small teratoma out of 35 grafts.

In this experimental model, it has been demonstrated that the primordial germ cells of the embryo are not responsible for the development of the neoplasms, but rather it is the somatic cells which are giving rise to these tumours. One must ask whether the controls which govern normal differentiation may become faulty and allow somatic cells to retain or regain their pluripotential nature making it possible, when conditions are right, to proliferate to form the "monstrous" tumour, teratoma.

abstract: Doctor of Philosophy (PhD)


title: The Interactions of Plasminogen with Model Surfaces and Derivatized Polyurethanes

contributor:
Brash, J.L.
Chemical Engineering

abstract:
The major complication limiting the usefulness of biomaterials in blood contracting situations is the activation of the coagulation pathways resulting in platelet activation and thromous formation at the surface. These events are initiated by the surface phenomena. The initial interaction is believed to be the adsorption of proteins onto the artificial surface followed by stimulation of cells and their subsequent adherence to the protein layer. The research presented in this thesis take the approach of making the surface typically interactive to achieve biocompatibility, and focuses on plasminogen, a plasma protein not previously studied in detail relative to blood interactions with artificial surfaces. The underlying working hypothesis of this research is that a potentially fibrinolytic, i.e. clot-lysing, surface may be formed via the specific and selective adsorption of plasminogen following blood contact.

Our approach was to create materials that would selectively adsorb plasminogen from blood by incorporating lysine residues (known to bind plasminogen) into the surface. Several different materials have been developed to facilitate this investigation: polyurethanes substituted with lysine derived from sulphonated precursors, classical polyurethanes, and model silica glass materials fictionalized with sulphonic acid groups and subsequently derivatized with lysine.

The model surfaces (silica glass, silylated sulphonated silica glass, and lysinated silica glass) were used to develop a method for the lysine derivatization of materials which results in incorporation of lysine at the surface with a free ε-amine group. Chemical and physical characterization of the surfaces utilizing ninhydrin reagent, contact angle and X-ray photoelectron spectroscopy were done and molecular modeling of silylated glass surface was undertaken. The data obtained indicate both qualitatively and quantitatively that the silylation and lysine fictionalization methods were successful.

Protein adsorption from buffer and from citrated human plasma was investigated on all materials. Generally, the plasminogen adsorption from buffer was Langmuirian. Surface concentrations corresponding to monolayer protein adsorption were observed at the isotherm plateaus. The sulphonated and lysine derivatized materials showed higher adsorption capacities relative to other surfaces. Adsorption studies on the model materials from pure buffer, included both adsorption and the desorption experiments in the presence of competing species, and suggest that the binding mechanism of plasminogen is different on each of the surfaces. It seems likely that the lysine binding sites are involved at least to some extent in the adsorption of plasminogen to lysinated materials.

The adsorption studies of fibrinogen and plasminogen from plasma suggest that plasminogen may be a possible contributor to the fibrinogen Vroman effect. In addition these studies provide further data in support of the contention that sulphonate groups have a strong influence on the adsorption of proteins in general. The plasma studies also show that the ratio of plasminogen to fibrinogen is greater on the lysinated than on the control on the sulphonated material, again indicating a specific influence of the lysine residues.

Data on the enzymatic activity of plasminogen adsorbed on the lysinated silica glass and its sulphonated precursor are reported. These studies provide information on the effect of lysine derivatization on the very important question of plasmin activity of adsorbed plasminogen. It was found that the plasminogen is no "plasmin-like" when adsorbed to any of the surfaces studied in this system. However in the presence of plasminogen activator there is a highly significant difference in the enzymatic activity of plasminogen adsorbed to the lysinated materials and to its sulphonated precursor. The lysinated material shows two-four times the plasmin activity on a mole basis compared to the sulphonated material. The implications of these findings for the development of fibrinolytic surfaces are discussed.

Preliminary investigations into polyurethanes derivatized using methods developed with the model materials are also reported.

abstract: Doctor of Philosophy (PhD)


title: The Image of the Goddess Durgā and Her Worship In Banāras

contributor:
Kinsley, David
Religious Studies

subject:
Religious Studies
Religion
Religion

abstract:
In this dissertation thick description provides the basis of an interpretive analysis of conceptual images of the goddess Durgā and her worship in Banāras, a city regarded as a microcosm of the Hindu tradition. The exploration begins at the renowned Durgā Kund temple which is studied synchronically. During the annual autumn festival (Navarātra), however, the focus shifts to typical forms of Durgā worship throughout the city, and the Durgā Pūjā ritual in particular.

A metaphysical portrait of Durgā is developed by concentrating on formal devotional worship (pūjā), blood sacrifice (bali), and the Nine Durgā Pilgrimage (yātra), three salient devotional acts especially related to Durgā worship in Banāra. The study shows that cosmologically and epistemologically Durgā is envisioned through a yogic science (vidyā) of energy (śakti) and material creation (prakrti). Ontologically, she provides a model of power, purity, orderly change, and maternal protectiveness from which worshippers may derive security within the cosmos. As a feminine image of the divine, Durgā offers different but complementary visions of reality to male and female devotees. The study suggests that the goddess offers women a model of chastity and strength, particularly in the face of misfortune. Despite the potential of this image to transform the traditional roles of women in Hindu society, this report offers evidence that Durgā sustains the orthodox social structure.

The study’s contribution to scholarship continues with its detailed interpretive description of Durgā temple worship and the Durgā Pūjā ritual. It also connects many of the threads which link the mythology, legend, and history of Durgā worship in Banāras. The interpretations of symbolic clusters and structural patterns (e.g., yantra) deepen our understanding of Śākistim, a major Hindu sectarian tradition. Since the study offers substantial evidence of the meaningful relationship between symbols and worship rituals, it critiques theories which deny such relationships.

abstract: Doctor of Philosophy (PhD)


title: Nutritional Control of Ascosporogenesis in an Apomictic Strain of Saccharomyces cerevisiae

contributor:
Miller, J.J.
Biology

subject: Biology Biology

abstract: An unusual strain of Saccharomyces cerevisiae that produces two-spored asci under conditions in which typical strains produce three and four-spored asci was investigated. It was possible to restore "normal" three and four-spored ascus production in this strain by manipulating the nutritional environment. The effects of nutritional factors supplied during the presporulation and sporulation phases were studied. The change in the proportion of three and four-spored asci was the major parameter employed to quantitate the effect of these factors on ascosporogenesis. Using the Giemsa nuclear stain, germination techniques, and genetic analysis, the number of spores per ascus was related to the manner of nuclear division in developing asci.

abstract: Master of Science (MS)


title: A Knowledge-Based Approach to The Design, Simulation, and Evaluation of Flexible Manufacturing Systems

contributor:
Elmaraghy, Hoda A.
Mechanical Engineering

abstract:
Launching new manufacturing systems for production is a difficult task which involves several people and resources, and is time-consuming and capital intensive. Flexible manufacturing systems (FMS), which are a new generation of manufacturing systems, further complicate this launching process because they consist of several interacting components such as workstations, pallets, automated material handling systems, and buffers. The lack of knowledge about the interaction between these components has often resulted in the poor performance of many FMS designs. Major corporations today are adopting a proactive philosophy rather than reactive one, and for a complex and capital intensive manufacturing system such as an FMS, the design process is extremely critical for its successful performance.

The design process, which precedes the launching of an FMS, is iterative and consists of planning, model development, and output analysis. While several computer-based tools are available for modeling and evaluating FMS designs, here is a dearth of such tools for synthesizing new design and analyzing output from simulation models to improve these designs. System designers have traditionally performed these two activities using their knowledge and experience. These are cumbersome and time-consuming activities and consequently increase the design cycle time.

The objective of this thesis is to reduce the FMS design cycle time by automating the design process. A knowledge-based system called FMX, Flexible Manufacturing Expert, was developed in this thesis to generate and evaluate designs of manufacturing systems with a high degree of automation. The object-oriented FMX is an intelligent system which combines expert systems and simulation modeling to design and evaluate flexible manufacturing systems. It consists of several modules, the major ones including an expert design synthesizer to generate initial system designs, a simulation models, and an expert analyzer to analyze simulation output, identity design deficiencies, and recommend changes. The current implementation of FMX was developed using the Knowledge Engineering Environment (KEE) expert system shell and the SimKit simulation package, and it runs on a Sun workstation under a UNIX operating system.

FMX has been applied for designing flexible manufacturing systems in the machining domain. Two case studies have been included in this thesis to demonstrate its capabilities-one of which includes industrial system used by a major automotive manufacturer in Ontario. The first case study took two iterations while the second one took three iterations to fine tune a synthesized design that satisfied various performance measures such as production volumes, equipment utilizations, equipment blocking, and queue length of automatic pallet changers. For both case studies, the investment cost per part index decreased for each iteration thus proving that the design changes suggested by the expert analyzer improved the performance of the initial system design while reducing the cost. The final output from FMX is a list of components that comprise the system, its graphical layout, and its performance measures.

FMX is a comprehensive decision support system which integrates all phases of a flexible manufacturing system design into a single software framework. Its modules such as the expert design synthesizer, simulation model developer, and expert analyzer each address a specific phase of the system design process. FMX generates consistent designs with the minimum intervention from the user and hence reduces the design cycle time significantly.

abstract: Doctor of Philosophy (PhD)


title: The Concept of Craving in Early Buddhism

contributor:
Younger, Paul
Religion

subject: Religion Religion

abstract:
The aim of this thesis is to show the soteriological significance of the concept of craving in early Buddhism. It is argued that more than any other single factor, craving is the central problem in early Buddhism, and that when properly understood, it can be seen as the crucial link holding the entire soteriological system of the Four Noble Truths together. Craving thus stands at the heart of the Buddha's gospel, and a correct interpretation of its complex and unique structure is essential for an adequate understanding of the Buddhist religion as a whole.

The concept of craving in early Buddhism is a theme that has not been adequately subjected to systematic analysis by Buddhist scholarship in the past. This study is undertaken in response to this deficiency.

Methodologically, this thesis investigates the concept of craving from both the phenomenological and the theological perspectives. It is not a semantic analysis of the word tanhā as such, but an attempt to get behind the general disposition indicated by that word, to see exactly what the Buddha meant when he said that to experience was 'to burn with thirst'. In one way, then, we must furnish a detailed phenomenological description of the origin, development and manifestation of craving as set down in the Pāli Nikāyas. In another way, however, we have an even more pressing responsibility as we attempt to interpret this data and give it meaning.

In order to best accommodate these aims, the thesis is divided into four parts. First we have to ascertain what primary textual sources we should use as the foundation of this study, and what the possible historical and theological problems are that we might encounter in understanding these sources. At the same time we review what scholarship has already been offered in this area, and establish our own approach and method.

Secondly, in order to see how craving is part of a much larger general theological structure, it is important to understand how it is related to the central Buddhist concept of painfulness (dukkha). Here the primary object is to see the psychological nature of this painfulness, and to examine how the early Buddhists described the psycho-physical structure of man.

Thirdly, we turn our attention specifically to how painfulness is provoked by grosser forms of craving. At this point our concern centres in upon the various mental factors which make up consciousness and unconsciousness. This is a strategic part of the thesis, for not only does it provide an in-depth study of the psychological structure of man, but it also demonstrates that the individual has the potential to control craving, and even use it as a positive force.

This lays the groundwork for part four, where we argue that in an important sense, craving has a definite soteriological value in early Buddhism. Here we investigate those passages which indicate the significance of conation in the Buddhist way (Magga), and show that even tanhā can be used as the instrument for its own purification, that it can be 'redirected' from deleterious aims to a more 'skilful' (kusala) form of intention. Only when this positive conative discipline has been undertaken can the individual fruitfully undertake the mindfulness (sati) and mediation (samādhi) necessary for insight (pannā) and thus enlightenment (nibbāna). In this final transcendent experience, craving of any kind is at last eradicated, its unconscious roots determined, and its relationship with painfulness at last fully understood.

It can be seen, then, that the central thesis concerning craving is woven into an entire framework of Buddhist soteriology, and that is cannot be properly understood as only a psychological phenomenon. For the early Buddhists, craving is of course partly a psychological dilemma. But unchecked and uncontrolled, it is also a serious obstacle in a spiritual sense, keeping the individual bound to ignorance and thus preventing the wholesome development of the mind and the transcending experience of enlightenment. In this sense, craving clearly is the ultimate soteriological problem in early Buddhism, yet it has often been taken out of its theological context and been inadequately understood.

The purpose of this thesis is to make a study of this central concept within the context of the religious system if Buddhism.

abstract: Doctor of Philosophy (PhD)


title: An Experimental and Theoretical Investigation of Vacancies and Hydrogen in Simple Metals

contributor:
Piercy, G.R.
Carbotte, J.P.
Materials Science

subject:
Materials Science and Engineering
Materials Science and Engineering

abstract:
An improved theory of vacancy formation energy and volume, based on local pseudopotential theory, is presented and applied to vacancies in the alkali metals and in aluminum. Good agreement with the existing experimental results is obtained.

The solubility of hydrogen in magnesium has been measured in the temperature interval 400°C - 600°C and for pressures 50 - 760 mmHg, from which the heat of solution of hydrogen has been determined.

A theory of the heat of solution of hydrogen is developed. The host lattice is treated with the local pseudopotential theory.

Nonlinear theory is used for the screening of the proton and a method for an approximate self-consistent solution proposed. The theoretical results for the heats of solution in aluminum and magnesium are in good agreement with the experimental values, particularly when one considers the magnitude of the numbers involved.

abstract: Doctor of Philosophy (PhD)


title: The Religious Philosophy in the Thought of Jose Vasconcelos: From the Atom to the Absolute

contributor:
John C. Robertson, Jr
Bar-Lewaw, Issac
Religious Sciences

subject: Religion Religion

abstract:
The purpose of this study is to investigate the religious thinking of José Vasconcelos (1880-1959). Vasconcelos was a Mexican thinker, politician and philosopher who worked out a theory of philosophical thought which he called Aesthetic Monism. In that title lies the key to an understanding of his philosophy: it is aesthetic because Vasconcelos felt that feelings and emotion best put the knower into contact with the known object, and it is monistic because Vasconcelos envisaged all reality unified in what he refers to as the Absolute or God.

Most of our knowledge of the Absolute and Vasconcelos' religious philosophical thinking are contained within his work, Todología. Therefore, for this as well as for other reasons, I have decided to analyze this work in detail. Our understanding of his religious thought, however, depends on our knowledge of how he approaches philosophy generally, and, in particular, how he conceives the nature and function of the aesthetic a priori.

Consequently, after the early chapters on his life and influences on his thought, I will spend some time surveying his philosophy, especially the way he conceives the instruments of the unification of reality. Vasconcelos wants to establish the unity of existence and in order to do this, he proposes a method of synthesizing various levels of reality -- cycles of being, in his terminology -- in an upward progression towards the highest levels of being. This is accomplished by human consciousness employing the instruments of the aesthetic a priori.

This thesis takes the view that the Todología aids, in outline form, the completion of this synthesis on the spiritual level of being, that of the absolute. I will argue that the synthesis needs this level and the activity of the absolute in order to attain the complete unity of existence which Vasconcelos set out to achieve. Our analysis of Todología in Chapter Four, consequently, is the heart of this study and I attempt to show in detail the necessity of the absolute for Vasconcelos' synthesis and, therefore, his contribution to religious philosophy.

The Union attempts to be both expositional and critical in character. I propose to outline only as much of his philosophical thinking as is necessary to comprehend his religious thought and thus avoid an exact duplication of other studies on his philosophy. At the same time, because Vasconcelos is controversial and, at times, inconsistent and vague, I intend to offer critical evaluations where appropriate, keeping in mind at all times, however, the nature of the men and the culture within which he formulated his thought.

abstract: Doctor of Philosophy (PhD)


title: Hippocampal Slice Studies of Kindling-Induced Epilepsy

contributor:
Smith, G.K.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
Repeated electrical stimulation of certain brain sites in animals leads to the progressive development of clinical seizures, a phenomenon known as kindling. The basic neuronal mechanisms underlying this effect may be similar to those involved in human epilepsy, but are not well understood. We have examined the properties of single neurones and populations of neurones in hippocampal slices derived from rats kindled in the hippocampus, fimbria/fornix, perforant path, or amygdala, and compared them with those of unstimulated animals.

At the neuronal population level, tissue from kindled rats did not display an increased tendency to generate spontaneous epileptiform activity. This as also the finding in ionic substitution experiments, where the levels of extracellular potassium were increased as high as 9 mEq/1. Electrical stimulation of afferents to the CA1 region evoked synaptically-mediated population responses which were similar to those of controls, except for tissue derived from rats kindled in the fimbria or in the amygdala. In these experiments, there was a tendency for multiple population spikes to appear in the responses to stimulation and this may reflect an increased excitability of the neuronal population.

Intracellular studies of hippocampal CA1 neurones from amygdala-kindled rats revealed that the basic activity and passive membrane properties did not differ from those of controls. However, the amplitude of the afterhyperpolarization following synaptic activation was increased in these neurones. In addition, the response to intracellular injection of depolarizing current was altered in some neurones, observed as an increased action potential discharge during the initial phase of depolarization.

These findings are discussed in terms of an apparent immunity of the hippocampus towards the development of chronic epileptogenic properties, and the ionic and membrane mechanisms which may be responsible for the observed differences between kindled and unkindled tissue.

abstract: Doctor of Philosophy (PhD)


title: Thermal decomposition of a Δ³-oxadiazoline

contributor:
Warkentin, J.
Chemistry

subject: Chemistry Chemistry

abstract: 2-Methoxy-2,5,5-trimethyl-Δ³-1,3,4-oxadiazoline was synthesized and decomposed neat, in the presence of carbon tetrachloride and in the presence of deuterated benzene. Because of the production of propene when C₆D₆ was the solvent and chlorinated products when CCl₄ was the solvent, a carbene mechanism is proposed. The evidence in support of this mechanism is strengthened by the trapping of the carbene intermediates with 1,1-diphenylethylene and the reaction of independently generated dimethylcarbene with CCl₄.

abstract: Master of Science (MS)


title: Sensation and Feeling: A Wave Theory Analysis

contributor:
Link, S.W.
Psychology

subject: Psychology Psychology

abstract: Wave Theory proposes that the relationship between sensation and feeling can be derived from a single theoretical foundation. The empirical evidence supporting this proposition is as of yet indirect: it is gleaned from comparative analysis of Weber Fractions and Stevens' exponents across numerous experiments of discrimination and magnitude estimation. Prior to examining the relationship, an extensive test of the assumptions and predictions of Wave Theory in the context of a discrimination task involving judgments of distance between successively presented pairs of dots was conducted. The primary purpose was to examine Wave Theory’s definition of sensation. This required the construction of symmetric stimuli which allow for analytic estimates of the model's parameters. The model was then tested by determining the correspondence between predicted and observed performance indices: response proportions and response times, and further between estimated response times and observed response proportions. The second experiment was conducted primarily to determine the empirical relationships among response proportions, response times, and magnitude estimates of the feeling of comparative distance. While the stimuli were again pairs of dots, the subjects also performed judgments of the magnitude of their perceived difference by squeezing hand held pressure sensitive devices. These judgments are inherent in the quantitative measure of feeling proposed by Wave Theory. The findings encouraged replication and consequently a more extensive experiment was carried out. This seminal work provides a comprehensive account of sensation and feeling and their empirical indices via Wave Theory analysis.

abstract: Doctor of Philosophy (PhD)


title: Adaptive Control of an Industrial Robot with Application To Arc Welding

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

subject:
Electrical and Computer Engineering
Electrical and Computer Engineering

abstract:
This thesis addresses the problem of position control of an industrial robot. The robot used for this study is a modified UNIMATE-2000 with five degrees of freedom, which is dedicated to research in arc welding applications.

The problem of position control of an industrial robot is first analysed. It is evident that due to several factors such as the elasticity of the arm, gravitational effects due to link orientation and load variations, a conventional fixed feedback controller is not adequate. It is therefore necessary to use an adaptive control scheme for position control.

It is well known that the dynamics of a robot are non-linear and coupled, because of which it is not convenient to derive control laws which can be implemented in real time. Further, because the dynamics change as a function of link orientation and load variation, the model has to be evaluated on-line.

In the past, robots were modelled from lays of classical mechanics. Although this scheme can result in accurate models, they are not suitable for adaptive control applications because of their complexity. In addition, this scheme of modeling requires a-priori knowledge of mass of links, specification of servo amplifiers and actuators. Often, to simplify models, dynamics of actuators and elasticity of links is neglected which results in unsatisfactory control.

In this thesis we describe a new method for modeling the robot. The model is derived from experimental observations and does not require knowledge of the structure and internal subsystems of the robot. Further, it includes actuator dynamics and the elasticity of the arm. The method is demonstrated by modeling one axis of the UNIMATE-2000.

Since the model is of non-minimum phase, the explicit pole-placement type of a self-tuning regulator was designed. Parameters of the model are updated at every sampling interval using a recursive Ieast squares estimator. Since, as mentioned before, dynamics of the robot change as a function of link orientation and Ioad variation, a 'weighting factor' is used for parameter estimation. Studies presented include the effect of truncation of controller parameters, adaptivity of the regulator to changes in system dynamics, and the effect of a variable weighting factor.

Finally, several aspects of implementation of the self-tuning regulator, including selection of the controller structure, selection of the microprocessor, AID, D/A converter and programming language are discussed.

abstract: Doctor of Philosophy (PhD)


title: National Science Policy in Canada; 1910 to 1920 and 1935 to 1945

contributor:
Grinnell, George James
History

subject: History History

abstract: This thesis is a study of national science policy in Canada from 1910 to 1920 and from 1935 to 1945. The formation of this policy is found to have often been beyond the political control of the federal government and to have been directed by both British and American political and industrial interests. In illustration of this fact is an examination of the development of the dominant industrial technologies and of the bureaucratic machinery of the public sector science organizations in combination with their aims to industrialize Canada and to exploit the use of natural resources. Throughout this study, the repeated overlapping of scientific developments and industrial technologies with military developments, as in the case of wheat, the refining of metals, and the development of the atomic power, reveals the strong inter-connections between industrial and political interests.

abstract: Master of Arts (MA)


title: A Simulation Study of Disequilibrium Macro Model with Special Reference to the Theory of Credit Rationing

contributor:
Scarth, William M.
Economics / Economic Policy

subject: Economics Economics

abstract:
The purpose of this study is to explore the implications for various government stabilization policies of explicit consideration of market disequilibrium, especially credit the commercial bank loan market. The analysis centers in each case on the value of the government expenditure multiplier.

First, a control or equilibrium version of the model is developed which is consistent with standard macrotheory and which contains a well-described banking sector. The results of the simulations with this version of the model confirm that the impact multiplier is larger when the deficit is financed by printing money than when bonds are issued to meet the requirement for funds. However, it is shown that in the long run the bond-financed multiplier is greater than the money-financed multiplier. This version of the model also confirms the possibility raised in the current literature that the bond-financed case may be unstable.

Since the current model has a well developed banking sector, the theory of the government finance restraint is extended to consider the case in which the deficit is financed by transferring the ownership of government bank deposits to the private sector. This case closely resembles the bond-financed case in the short run but it is statically stable. The deposit-financed case is limited, of course, by the initial size of the government deposits. Therefore, the restoration of the level of government deposits by one of the other means of financing is considered.

Next, a disequilibrium version of the control model is developed consistent with current literature on disequilibrium phenomena. This version of the model contains a feedback mechanism by which a disequilibrium in one market will affect the decisions in all other markets.

The results of the simulations with the disequilibrium model show that the government expenditure impact multiplier may be increased by the presence of credit rationing. In fact the bond-financed case which is unstable in the control version becomes stable under "equilibrium" credit rationing, where the loan rate does not adjust at all.

Since the model used in this study is ad hoc, sensitivity analysis is used to investigate the importance of the exact values of the key parameters of the system. The policy implications of the study do appear to hing on the values of the feedback coefficients. If the force of credit rationing is mainly felt in the real sector, the government expenditure impact multiplier will be smaller in the disequilibrium version than the control model. On the other hand, if the impact of credit rationing is mainly felt in the financial sector, the opposite result will occur. However, the range of values that the multiplier may take on, depending on the impact of the credit rationing, is quite small.

Thus, given the size of the error of prediction of standard models, this study concludes that it is unlikely that the inclusion of credit rationing will allow a better evaluation of government stabilization policies. This is especially true if the impact of credit rationing is believed to be in roughly the same proportion as normal expenditures in the various markets.

abstract: Doctor of Philosophy (PhD)


title: Annotated Check-List Bibliography Bibliography Handbook

contributor:
Hammond, A.
English

subject:
English Language and Literature
English Language and Literature

abstract: Twentieth-century writers present distinct problems for the academic, the bibliographer and the biographer. Popular authors often write not only novels and short stories, but also plays for the stage as well as television, commissioned pieces for large and small magazines and journals, children's books, essays, travel books and articles as well as book reviews. The large and diverse canon of Edna O'Brien illustrates the complex and difficult nature of researching modern authors. The thesis describes the methodology of such research, outlining problems and creative, often unorthodox approaches required to obtain information. The Handbook section is intended to provide a guide for other researchers. It lists reference sources, methods of organizing material, computer searches and particularly focuses on the problems of unpublished material. The annotated check-list bibliography lists published and unpublished works by Edna O'Brien. This section is followed by one of criticism, interviews and reviews of O'Brien's work. O'Brien's reputation in academic circles as well as in the literary press is anything but established. Each new publication creates clashes and controversy. The nature of the research presented in this thesis provides opportunities for a different approach to criticism of O'Brien. The final chapter briefly explores these opportunities.

abstract: Doctor of Philosophy (PhD)


title: Mathematical Models Involving Multiple Resource Limitation

contributor:
K., G. S.
Mathematics

subject: Analysis Mathematics Analysis

abstract:
A model of the chemostat involving two populations of microorganisms competing for two perfectly substitutable resources is developed and analyzed. A general class of functions is used to describe nutrient uptake, one which allows for the effect that the concentration of each resource has on the amount of the other resource consumed. The model significantly generalizes those previously studied. The dynamics of this model are then compared with the dynamics of the classical growth and two-species competition models, as well as models involving two perfectly complementary resources.

It is not surprising that the above competition for two resources can result in the coexistence of the two competitor populations. However, an example is also given in which the extinction of one population is averted by the introduction of its competitor. Thus, exploitation of common resources promotes diversity in some circumstances. This situation is investigated further and a more general description is given.

A model of single-species growth on two resources is then presented. For a given dilution rate, the medium in the growth vessel is enriched by increasing the input concentration of one of the resources. Enrichment is considered beneficial if the carrying capacity of the environment is increased. Analytic methods are used to determine the effects of enrichment on the asymptotic behaviour of the model for different dilution rates. The existence of a threshold value for the dilution rate is established. For dilution rates below the threshold, enrichment is beneficial, regardless of which resource is used to enrich the environment. When the dilution rate is increased beyond the threshold, it becomes important to consider which resource is used to enrich the environment. For one of the resources it is shown that, while moderate enrichment can be beneficial, sufficient enrichment leads to the extinction of the population. For the other resource, enrichment leads from washout or initial condition dependent outcomes to survival, and is thus beneficial.

The growth model is then extended to include a single predator population. Using the threshold value for the dilution rate established in the growth model, the effects of enrichment on the asymptotic behaviour of the resultant predator-prey model are investigated. Here, enrichment is considered beneficial if it can lead from washout for some positive initial conditions to survival of both species for any positive initial conditions. For dilution rates below the threshold, enrichment is beneficial, regardless of which resource is used for enrichment. As in the growth model, it becomes important to consider which resource is used to enrich the environment when the dilution rate is above the threshold. For one of the resources, moderate enrichment can be beneficial, while sufficient enrichment leads to a regime in which washout is possible. For the other resource, sufficient enrichment is beneficial.

abstract: Doctor of Philosophy (PhD)


title: Active Site Interactions in Proteolytic Enzymes

contributor:
Chan, W.W.-C.
Biochemistry

subject:
Enzymes and Coenzymes
Virus Diseases
Enzymes and Coenzymes

abstract:
The HIV-1 virus encodes a protease essential for the processing of polyprotein precursors into mature viral proteins. This enzyme is a primary target for drug design against AIDS. Concurrent effects of inhibitors targeted to defined regions of the extended active site were investigated using Yonetani-Theorell kinetics to understand its complex specificity requirements. Kinetic data revealed that the simultaneous presence of two specific inhibitors may increase their binding affinity for the enzyme. A 100-fold enhancement in binding affinity was observed in certain instances. Results from this work showed a correlation between inhibitor synergism and substrate specificity thus implicating subsite interactions in enzyme catalysis.

To facilitate the analysis of enzyme-inhibitor interactions an improved graphical method, the combination plot, was developed as an alternative to the Yonetani-Theorell plot. The method generates a single straight line rather than a family of lines which is the traditional approach in such kinetic studies. The slope of the plot, 1/α, quantitatively measures the extent and nature of interaction between two inhibitors on their target enzyme. The approach was easily extended to analyze, for the first time, the interaction between three competitive inhibitors on an enzyme. The combination approach potentially has broad applications for kinetic analysis.

Combination plots were used in the discovery of gem-dialkyl succinic acid derivatives as a new class of unusually potent reversible inhibitors of carboxypeptidases A and B. 2-Ethyl-2-methylsuccinic acid binds to carboxypeptidases A and B with dissociation constants of 1.1 X 10ˉ⁷ M and 3.4 X 10ˉ⁶ M respectively. The low dissociation constants of the inhibitors for the zinc proteases can be attributed primarily to the gem-dialkyl groups which presumably make very important hydrophobic contacts within the active site. The inhibitors may also act as zinc ligands while possessing sufficient affinity for the carboxyl-recognition site in the enzymes.

abstract: Doctor of Philosophy (PhD)


title: Studies on the Subunit Interactions in Aspartate Transcarbamylase

subject: Biochemistry Biochemistry

abstract:
The effects of subunit interactions on the function of aspartate transcarbamylase from Escherichia coli have been investigated by the characterization of an intermediate formed during the reassembly of the native enzyme (c₆r₆) from its constituent catalytic (c₃) and regulatory (r₂) subunits. The intermediary complex was formed by mixing a low concentration of c₃ with excess r₂ and under these conditions was stabilized against reassociation to the native c₆r₆ structure. Sucrose density gradient analysis indicated that the complex sedimented at a position intermediate between the native enzyme and the catalytic subunit. These and other results indicated that the complex has the structure c₃r₆. Similar sedimentation experiments showed the reversibility of c₃r₆ formation and its conversion to c₆r₆ at low r₂ concentrations.

While the native enzyme gives markedly sigmoid initial velocity kinetics with respect to the substrate aspartate the c₃r₆ complex gives a hyperbolic dependence similar to c₃ but with a much reduced Km. The high affinity of c₃r₆ for aspartate suggests that the complex may represent the relaxed state of aspartate transcarbamylase. Further evidence for this was provided from studies of the pH activity profiles of the various enzyme forms.

Although both regulatory and catalytic subunits are present in the c₃r₆ complex the allosteric inhibitor CTP and activator ATP were found to have no effect on c₃r₆.

abstract: Doctor of Philosophy (PhD)


title: The Effects of Tissue Antisera Injected in the Pregnant Rat on the Development and Function of the Placenta

contributor:
McCallion, D.J.
Materials Science

subject:
Medical Sciences
Medical Sciences

abstract:
Sera raised in rabbits against adult rat kidney has long been known to be teratogenic when administered to pregnant rats at a time when the embryos are in the gastrulation stage. The main hypothesis postulated on the mode of action of teratogenic kidney antiserum is that the antibodies directly interfere with placental development and function; thus resulting in a nutritional deficit to the embryo. A nutritional deficit is believed to interfere with embryonic morphogenesis. To date no investigations have been performed on placental function and development.

In the present investigation, histological and histochemical techniques were used to study the effects of kidney antiserum administered to the pregnant rat on the development and function of the fetal placental structures.

The results of this study have demonstrated that both the visceral yolk sac and chorio-allantoic placentae were adversely affected. The effects of kidney antiserum on the visceral yolk sac is consistent with an interpretation of an inhibition of nutrient uptake. The development of the chorio-allantoic villi and the allantoic vasculature was markedly retarded. The effects of kidney antiserum on the fetal placental structures suggest that the embryo undergo a nutritional deficit.

Glycogen and protein content of the maternal placenta was also investigated. The glycogen content was significantly lower in experimental rats as compared to controls. However, this difference was not noted until 72 hours after the administration of the kidney antiserum. This was a time when the embryos were not very susceptible to teratogenic antiserum insult.

Localization of kidney antibodies was also performed. The antibodies were demonstrated to be present within the embryo proper, amnion, parietal yolk sac, chorion and allantois.

Numerous Feulgen positive necrospherules were also observed within the embryo proper within 12 hours after the administration of kidney antiserum.

The observations of the present study is thus consistent with the interpretation that the cause of kidney antiserum teratogenesis is an effect of kidney antibodies on placental function and development resulting in a nutritional deficit to the embryo and/or is a direct effect of kidney antibodies on the integrity of the cells of the embryo proper.

Both control and experimental trophoblast shells contained islets of cells. These islets, not previously reported in the literature, contained mitotic figures. It is suggested that these islets are the proliferation sites of the trophoblast shell.

abstract: Doctor of Philosophy (PhD)


title: Synthetic Oligoribonucleotides: A Messenger RNA and Purification of Isoleucine Transfer RNA by Affinity Chromatography

contributor:
Neilson, Thomas
Biochemistry

subject: Biochemistry Biochemistry

abstract:
Chemical synthesis of oligoribonucleotides has been applied to two problems of biochemical interest. The synthesis of a model messenger RNA coding for N-formylmethionylangiotensin and use of a synthetic tetranucleotide (ApUpCpA) bound to cellulose for affinity chromatography of isoleucine tRNA were proposed.

Synthesis of the required tri- and tetranucleotide blocks for assembly of the thirty nucleotide messenger sequence was carried out by the phosphotriester method developed by Neilson. In this method, a nucleoside destined to become the 5'-terminal residue, protected with the acid labile 2'-0-tetrahydropyranyl group, and except for uridine an N-benzoyl group, is further protected by a 5'-triphenylmethoxyacetyl group which can later be removed selectively. This protected nucleoside is phosphorylated at the 3'-hydroxyl with 2,2,2-trichloroethylphosphate which is subsequently coupled to the 5'-hydroxyl of the second nucleoside, protected as the original one. Addition of further nucleosides is accomplished by the same two step procedure. Yields of coupled products appeared to depend upon the sequence and nucleoside being coupled, and ranged from 20-70%.

Relative rates of hydrolysis of the 5'-protecting group and N-benzoyl groups also depended upon the sequence of nucleotides used and an undesirable extent of loss of N-benzoyl groups was found particularly in sequences containing adjacent adenosine and cytidine residues or cytidine and cytidine residues. Results obtained in these reactions were adequate to allow two block coupling reactions to be attempted, and the products of these two coupling reactions were isolated. However, on completely deprotecting these products, the yields of the expected oligonucleotides was 0%, precluding further characterization. After complete deprotection of the shorter oligonucleotides, synthesized by the stepwise addition of nucleosides, low but adequate yields were obtained which allowed contribution of their structures.

These unexpected difficulties with the apparently unique properties of different protected oligonucleotides together with the length of the synthetic pathways involved resulted in the decision not to continue towards the objective sequence. The sterically hindered mechanism of coupling and possible binding to and degradation by Zn/Cu couple used in complete deprotection steps were discussed to account for these difficulties, especially with longer sequences. Potential solutions, based on these hypotheses were proposed.

The decision was also made to proceed with the application to affinity chromatography.

Model studies demonstrated feasibility of incorporating 5'-phosphates or 3'-phosphate-linked decane diol as possible sites for attachment of the affinity site to cellulose. Coupling of protected sequences to cellulose via phosphodiester or triester linkages were not suitable, but coupling to cellulose via phosphodiester after deprotection was demonstrated. Affinity chromatography of isoleucine labelled and leucine labelled bulk-tRNA did not indicate evidence for specific binding.

Theoretical treatment of the affinity experiment showed the validity of the idea and suggested that availability of binding sites was the critical parameter. Nuclease digestion of the oligonucleotide cellulose confirmed this hypothesis. Consideration of other matrices, spacers and coupling methods, as well as improvement of yields on deprotection were recommended in order to increase the availability of binding sites.

abstract: Doctor of Philosophy (PhD)