title: Title: Laser Induced Self-Action Phenomena in a Photopolymerisable Medium, Author: Ana B. Villafranca, Location: Mills

contributor:
Krantzberg, Gail
Civil Engineering

abstract: Title: Shared Water Resources in the Great Lakes and in the Jordan River Basin: Comparative Models in Inter-Juristicational Water Management, Author: Abdel R Darwish, Location: Mills

abstract:
The period from 1909 to 1987 could be characterized as achieving notable successes in the management of the Great Lakes waters. The successes during this interval provide important lessons for shared water resources elsewhere. However, the period from 1987 forward saw more obstacles in restoring and maintaining the waters in the Great Lakes
basin. Since 1987, progress toward delisting and restoring beneficial uses in the most degraded locations known as the geographic Areas of Concern (AOCs) (e.g. the St. Clair and Detroit Rivers) has been slow. Cleanup and restoration actions have been completed for only five of the 43 AOCs that were identified in the Great Lakes basin. Meanwhile, in the Jordan River basin, various bilateral agreements were signed to divide and manage
the water resources but with little success, with the exception of the successes achieved between Jordan and Israel on the Aqaba Gulf. These successes provide lessons for other parts in the world that are attempting to achieve effective transboundary environmental outcomes. This thesis examines the factors that impede progress in the restoration of the
beneficial uses in the St. Clair and Detroit Rivers AOCs and provides recommendations to advance implementation of the restoration process for the two rivers. This thesis also examines the conflict and the agreements over the shared water resources in the Jordan River basin and proposes a model consisting of three elements (political, socio-economic,
and scientific) to create sustainable solutions to the water problems and improve management of the shared water resources in the basin based on the historic successes achieved in the Great Lakes region. A comparative analysis of the management of sharedwater resources between the two basins provides a series of principles that are applicable to shared water resource management in other parts of the world.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Reading Women in Late Medieval England

contributor:
Grise, Annette C.
English

abstract: Title: Reading Women in Late Medieval England, Author: Stephanie Morley, Location: Mills

abstract:
This dissertation examines and identifies the ways in which devotional
activities became feminized textual practices in the later Middle Ages. Tracing
the vicissitudes of elite women's involvement in the production and dissemination
of a series of devotional texts, Reading Women in Late Medieval England offers a
new critical lens through which to better understand women's involvement in the
literary culture of the late Middle Ages by focusing on the historical figure of the
aristocratic laywoman reader. It pursues her influence across a generic range of
devotional material in English and French, from female hagiography to didactic
prose to prayer, including translations undertaken by women. The texts under
consideration here, ranging in date from the mid-fifteenth to the early sixteenth
centuries, represent the most popular books in medieval libraries and arose in a
context of growing vernacular literacy and a movement toward affective forms of
piety. Drawing on a number of fifteenth-century sources, including wills,
household accounts and library inventories, the project recognizes the
fundamental and specific engagement of women with some of the most important
developments in vernacular literature, late medieval spirituality and book culture.

Falling easily into two sections, the first two chapters of this study focus
on manuscripts commissioned for or by women readers and examine the ways in
which the presence of specific women readers enters into the text. The second
two chapters shift the focus to early printed books and take up the issues
surrounding the presence of the woman reader as patron and the development of her cachet with respect to devotional literature made available to a broad and
diverse audience. Reading women back into the leaves of the books they read,
owned and commissioned, I investigate their presence via two prevalent
metaphors: that of speaking and that of seeing. The voice and visibility of the
elite woman reader, available in rare and rarely read texts, allows me to
reconsider and refigure late medieval devotional literature not as a genre
fashioned for women, but as a genre fashioned by women.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Biophysical and Economic Analysis of Black Spruce Regeneration in Eastern Canada using Global Climate Model Productivity Outputs

contributor:
Arain, Altaf
Environmental Science

subject: afforestation, reforestation, growth and yield model, carbon sequestration, forest economics

abstract: This study explores the biophysical potential and economic attractiveness of black spruce (Picea mariana) regeneration in eastern Canada under future climate changes. It integrates process-based ecosystem model simulated forest productivities from three major global climate models (GCMs), growth and yield formulations specific to black spruce and economic analyses to determine the overall investment value of black spruce, both including and excluding carbon sequestration benefits. Net present value (NPV) was estimated to represent the financial attractiveness of long-rotation forest plantations through time. It was assumed that stands would not be harvested at volumes less than 80 m3 ha-1. The price of stumpage was set to $20 m-3, stand establishment cost was set to $500 ha-1, and the discount rate was considered at 4%, with sensitivity analyses conducted around these assumptions. The growth and yield of black spruce was simulated for an extreme future climate scenario – IPCC-RCP 8.5. The results suggested a general North-South gradient in forest productivity where gross merchantable wood volumes increased with decreasing latitudes. This pattern was also observed in NPVs, with higher values projected for the southern portion of the study area. Based on the base economic assumptions and sensitivity analyses, study results suggested that black spruce plantations are not economically attractive, unless carbon sequestration benefits of at least $5 ton-1 CO2 are realized. Further sensitivity analyses showed that discount rate plays a significant role in determining the optimal harvest age and value. Furthermore, the optimal harvest rotation age increases with increasing carbon price by approximately 9 to 18 years.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Embodied Experiences of Pregnancy: Learning, Doing and Attaching

contributor:
Bourgeault, Ivy L.
Sociology

abstract: Title: The Embodied Experiences of Pregnancy: Learning Doing and Attachment, Author: Elena Neiterman, Location: Mills

abstract:
This dissertation investigates the socially and physically embodied experience of pregnancy. Analyzing qualitative interviews with 42 culturally diverse women of different ages and social classes, I explore the meaning women attach to pregnancy and its impact on their relationship with others.

Theoretically, this research is grounded in the intersection of the sociology of the body and the sociology of pregnancy and childbirth. Focusing on women's embodiment of pregnancy I reinstate the importance ofthe physical component of pregnancy within the literature on pregnancy and childbirth, which predominately deals with social pregnancy rendering the physical body an "absent presence". At the same time, I seek to reiterate the importance of social interactions in the field of sociology of the body which, concentrating on physical body, often neglects the social meanings attached to physiological transformation. I contribute to both fields of study demonstrating that treating physical as real is as wrong as analyzing social experiences of pregnancy without mentioning physical bodies.

My major argument is that the meaning that pregnant women and people around them attach to pregnancy is constantly re-negotiated in social interactions. I claim that despite the physiological transformation that women undergo during pregnancy, the pregnant body is not socially pregnant until it is defined as such during interactions with others.

Situating women's experiences in the context of North American medicalized culture of pregnancy, this dissertation also examines how women's journey to motherhood is shaped by their social context and what effect the medicalization of pregnancy have on women's embodiment of motherhood.

I conclude this dissertation exploring the role of social context in shaping the embodied experiences of pregnancy and reflecting on the dynamics of social and physical in the study of pregnancy and transformations of corporeal yet socially positioned bodies.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Chidiac, Samir E.
Civil Engineering

abstract: Title: Packing Density Links Concrete Mixture, Rheology, and Compressive Strength, Author: Fayez Moutassem, Location: Mills

abstract:
Concrete is a mixture of cement, aggregate and water, whose properties, both fresh and
hardened, depend on its composition. Establishing a link between the concrete mixture,
the rheological properties of fresh concrete, and the compressive strength of hardened
concrete provides a predictive tool for designing the rheology and the compressive
strength on the basis of its constituents. Research has shown that packing density, which
is a function of the constituents, influences the rheological and the compressive strength
properties of concrete. Accordingly, it is postulated that packing density, a fundamental
property, is the link. On this basis, representative models for rheology and compressive
strength that employ packing density as a central variable have been developed for the
latter and adopted from literature for the former.

A fundamental approach was undertaken to develop a mathematical compressive strength
model that is function of packing density and the concrete mixture. The proposed model
accounts for the type of cement, cement degree of hydration, type and gradation of
aggregates, mixture proportions and porosity. An experimental program was developed
on the basis of fractional factorial design to implement, calibrate and validate the strength
model. An evaluation of published models was then carried out in which the rational,
limitations and potential use of these models were discussed. In addition, the applicability
and accuracy of these models for different ages were investigated and compared to the
proposed model using a large amount of data obtained from literature. Results reveal that
the proposed model is one of the most representative and accurate models providing the
highest predictability with a correlation factor of 0.93.

A methodology for the postulated link, which provides a quantitative approach to design
concrete mixtures to meet specific strength requirements and rheology, was proposed.
The strength model developed for this purpose and the adopted rheological models were
identified. An experimental program was developed to assess the postulated link. Results
reveal that packing density links concrete mixture, rheology and strength. This was
confirmed through successful generation and application of correlation nomographs
whose trends were found consistent with what has been reported in literature.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Coleman, Daniel
English and Cultural Studies

abstract: Title: A Literary History of Six Nations of the Grand River, Author: Rick Monture, Location: Mills

abstract:
While not a entirely a "literary history" in the usual sense of the term, Teionkwakhashion tsi Niionkwariho:ten ("we share our matters") collects the words of political leaders, traditional knowledge carriers, orators, authors and artists that speak to the experience of the Six Nations of the Grand River community. This dissertation's intended purpose is to demonstrate the ways in which these various individuals including Joseph Brant, Pauline Johnson, Seth Newhouse, Deskaheh (Levi General), Enos Montour, Alma Green, Chief Jake Thomas, Brian Maracle and Shelley Niro have expressed a unique Haudenosaunee perspective about ourselves and our relationship to the natural world, and to others, since our relocation to southern Ontario from our traditional homelands in New York State following the American Revolution. This is a world view comprised of three distinct features: a spiritual belief about our role and responsibility on this earth; a firm understanding of our sovereign status as a confederacy of independent nations; and our ongoing responsibility to maintain this state of being for future generations.

Referring to letters, speeches, poetry, ethnographic writing, fictional history, (auto)biography and film, I argue that these core beliefs of Haudenosaunee identity have remained remarkably consistent over the past two hundred and twenty five years. This does not in any way suggest a stagnant, conservative belief system in our community, but rather a constant re-negotiation of culture that draws upon our intellectual traditions in order to address the situations that we face today. We may have divided on certain political, social and economic issues at different times, but in the process of debating our positions, we are forever engaging with our oral traditions, cultural philosophies, past histories, and contemporary realities. This is what keeps traditional culture vibrant, dynamic, and useful to us as Haudenosaunee in the 21st century.

This dissertation is unique in that it is the first to collect these particular works in chronological fashion and to consider them as a unified body of writing, exploring the moments of resonance and points of departure from one another. Much has been made recently about the struggle for our land rights as well as the Canadian government's acknowledgement of our traditional government's authority to negotiate for these lands. As my project shows through the examination of selected works, this struggle for rights and recognition is nothing new to us. This study is, also, far from exhaustive. There are many, many other notable orators, traditionalists, writers and artists from Grand River who could have been included here, with much the same result. Our stories, in whatever form they may appear -spoken or sung in our original languages, written in English, or captured on film -have provided the foundation of our identity for centuries, and will continue to do so.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: DEVELOPMENT OF A MICROFLUIDIC OXYGENATOR AS AN OXYGENATING UNIT OF A LUNG ASSIST DEVICE FOR TERM AND PRE-TERM NEONATES WITH RESPIRATORY DISTRESS SYNDROME

contributor:
Selvaganapathy, Ponnambalam
Mechanical Engineering

subject:
Microfluidic
Oxygenator
Respiratory Distress Syndrome
Neonate
Artificial Placenta

abstract:
Respiratory distress syndrome is a major cause of mortality among infants. Current therapies are limited in terms of invasiveness, cost, infrastructure, and leads to long term morbidities such as bronchopulmonary dysplasia. As a result a form of respiratory support termed as “artificial placenta” has been developed that allows natural development of lungs and avoids long term morbidities. The artificial placenta is connected via the umbilical vessels and provide pumpless respiratory support and is characterized by non-invasiveness, low cost and low infrastructure. Our group previously reported on a development of porous PDMS membrane artificial placenta. To build upon its development, one of the objectives of this thesis was to reduce the variation in the oxygen saturation of the input blood for testing the oxygenator. Another objective was to setup a mathematical model to predict the oxygen uptake in an oxygenating unit and use the model to optimize the geometric parameters of a design. The final objective was to improve the oxygen uptake of the oxygenating unit of the artificial placenta by redesigning the blood flow path and the membrane material.
The experimental setup was improved to employ an active controller that actively maintained the oxygen saturation of the input blood for testing the oxygenator within a variation of ±3% of the set point for at least an hour. As compared to previous experimental setup the blood deviated from the set point by 9%.
Later, the blood flow path in the oxygenator was redesigned from a flat height profile to a sloping height profile; and the PDMS membrane was reinforced with a thin steel mesh. Such changes improved the oxygen uptake at the operating pressure of 30 mmHg from 16 µL/min in case of an oxygenator with flat height profile and PDMS membrane to 26 µL/min in case of an oxygenator with flat profile and composite membrane.
Finally, a mathematical model was developed that coupled oxygen uptake, pressure drop and membrane expansion. The model was validated against experimental results and was later used to optimize the configuration of the oxygenator with sloping profile and composite membrane. The predicted oxygen uptake of the optimized configuration at the operating pressure of 30 mmHg was 78.8 µL/min.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Wrestling with the Nature of Expertise: A Sport Specific Test of Ericsson, Krampe and Tesch-Römer's (1993) Theory of "Deliberate Practice"

contributor:
Starkes, Janet L.
Kinesiology

subject: wrestling, nature, expertise, sport, specific, Deliberate Practice, theory, Ericsson

abstract: Ericsson, Krampe and Tesch-Römer (1993) have concluded from work with musicians that expertise is the result of "deliberate practice". So how valid is this conclusion in sport? Four groups of wrestlers (n=42); 2 international and 2 club (current & retired) recalled the hours spent in wrestling activities since beginning wrestling. All groups had begun at a similar age (M =13.2 ± 0.6year) and had been wrestling for 10 years or more. Contrary to Ericsson et al., practice alone activities did not discriminate between the groups, only practice with others. At 6 years into their careers, the international group practised 4.5 hour/week more than the club wrestlers and at age 20 years the international wrestlers had accumulated over 1000 more hours of practice with others. Evaluations of wrestling activities showed that those judged as relevant, were also rated high for concentration and enjoyment. Diary data were collected from current wrestlers, however, no differences were found for time spent in wrestling activities. The international wrestlers spent longer travelling to practice, which reflected the necessity to train at a club with the best sparring partners. Practice with others yielded high correlations between estimates for a typical week and the diary data for the international wrestlers only, suggesting a more consistent training schedule for this group. In conclusion Ericsson et al.s' definition of "deliberate practice" needs to be reconsidered. It is suggested that "maintenance" hours should be considered separately from practice, and that future studies focus on what it is that motivates people to practice.

abstract: Thesis

abstract: Master of Science (MSc)


title: Syntheses and Structural Characterizations of New Inorganic Anhydrous Borate Compounds

contributor:
Barbier, Jacques
Chemistry

subject: syntheses, structural, characterizations, inorganic, anhydrous, borate, compounds, crystal

abstract: A number of new ternary borate compounds have been synthesized, and their crystal structures have been characterized via X-ray and neutron diffraction techniques. A series of new compounds with the composition PbMBO4 (M = Cr, Mn, Fe, Ga) has been prepared from solid-state reactions and from single crystal growths using PbO as a flux. They crystallize in the orthorhombic Pnma space group and represent a new structure-type for the family of anhydrous borates. The PbAlBO4 compound undergoes a phase transformation at high temperatures, which has been investigated by in-situ powder neutron diffraction experiments. The structure of β-PbAlBO4 has been solved from powder X-ray diffraction data and subsequently confirmed by a Rietveld refinement of powder neutron diffraction data. The investigation of the SrO - Ga2O3 - B2O3 system has led to the synthesis of a new structure-type, SrGaBO4, from solid-state reactions. Its crystal structure has been determined from powder X-ray diffraction data. It crystallizes in the orthorhombic Pbam space group, and is structurally related to the previously known alumino-borate compounds, SrAlBO4 and CaAlBO4. The "Ba2Ti2B2O9" compound has been re-formulated as Ba3Ti3B2O13, and its crystal structure has been determined by single crystal X-ray diffraction. This compound crystallizes in the non-centrosymmetric P6 2m space group. It is isostructural with K3Ta3B2O12 and the high temperature phase of K3Nb3B2O12.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Lyons, J. L.
Kinesiology

abstract: Title: The Influence of Direct Action Possibilities on Movement in Individuals with Autism Spectrum Disorder, Author: David A. Gonzalez, Location: Mills

abstract:
The method by which individuals plan and execute movements is highly
dependent on the environmental and task constraints. However, the way in which
individuals view the world and objects differ amongst the population. This has profound
implications for individuals who may have difficulties planning movement. There is
growing evidence that individuals with Autism Spectrum Disorder have not only deficits
in communication, but also in motor control (Glazebrook et al., 2009; Rinehart et al.,
2006). Therefore, it is imperative to understand how and why these motor control
differences arise in individuals with ASD and if there are ways in which these
impairments could be alleviated. There is evidence demonstrating that brain connectivity
in individuals with ASD may differ compared to controls (Frith, 1989). This may
contribute difficulty when integrating highly cognitive information. Therefore, objects
and scenarios that afford a high degree of action-perception coupling were explored to
determine if (and how) individuals with ASD can use this more direct coupling to aid in
the planning and execution of movement. Furthermore, we explored if these processes
could be applied to interactions with other individuals. The findings of the study
demonstrated that individuals with ASD did not appear to use the orientation of a handle
(study one) to pre-plan responses to graspable objects (c.f. Tucker & Ellis, 1998).
However, when the action component was further emphasized in the second study, the
accuracy scores obtained were comparable to those of chronologically age and sex
matched controls. This supports the notion that objects with high action-perception
coupling can be used successfully by individuals with ASD to interact with other individuals. The findings of study three demonstrated that individuals with ASD used the
intended actions of a confederate to solve a Theory of Mind task, and thereby anticipate
the motor intentions of the confederate. Overall, the findings of the dissertation suggest
that the use of objects and scenarios that afford a high degree of action-perception
coupling seems beneficial for individuals with ASD as they are able to use these objects
to anticipate the possible actions that another individual may perform.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Galvanization of Al-Si Trip-Assisted Steels

contributor:
McDermid, Joseph R.
Materials Science and Engineering

abstract: Title: Galvanization of Al-Si TRIP-Assisted Steels, Author: Erika M. Bellhouse, Location: Mills

abstract:
The high strength and ductility of TRIP-assisted steels makes them ideal for
automotive lightweighting. However, to be used in automotive exposed parts galvanizing
is essential to provide corrosion protection. Galvanizing of TRIP steels poses two major
challenges: i) the heat treatment used to obtain the TRIP steel microstructure and
mechanical properties is not necessarily compatible with the higher temperatures required
for hot-dip galvanizing and ii) selective oxidation of the alloying elements used in TRIP
steels; Mn, Si and Al, can result in bare spot defects and unacceptable coatings. Both of
these issues have been investigated.

Heat treatments compatible with continuous hot-dip galvanizing were performed
on two high Al - low Si TRIP-assisted steels; one having 1.5% Al and the other having
1.0% Al and 0.5% Si. The effect of intercritical annealing (IA) temperature and
isothermal bainitic transformation (IBT) time at 465 °C on the development of
microstructure and mechanical properties was studied. It was determined that a sufficient
quantity of stable retained austenite and an excellent combination of strength and
ductility could be obtained using thermal cycles with a 465 °C IBT temperature. For the
1.5% Al steel the best combination of strength and ductility was obtained for the thermal
cycle using the 50% austenite (y) IA temperature and IBT times of 90 sand 120 s. For the
IBT time of 90 s the tensile strength was 895 MPa and uniform elongation was 0.26. For the
IBT time of 120 s the tensile strength was 880 MPa and uniform elongation was 0.27. For
the 1.0% Al - 0.5% Si steel the best combination of strength and ductility was obtained forthe 50% y IA temperature and IBT time of 120 s. This thermal cycle resulted in a tensile
strength of 1009 MPa and a uniform elongation of 0.22.

The effect of process atmosphere oxygen partial pressure on oxidation and
reactive wetting during galvanizing was determined for four TRIP-assisted steels having
varied Si and Al contents. Three different process atmospheres were studied for each
alloy: a -53 °C dew point (dp) or-50 °C dp with N2 -20% H2 , a -30 °C dp with N2 - 5%
H2 and a +5 °C dp with N2 - 5% H2 . The steel chemistry and oxygen partial pressure of
the process atmosphere affected oxide chemistry and morphology. For all alloys the
lowest oxygen partial pressure process atmosphere resulted in the highest concentration
of Si at the surface (-53 °C dp or -50 °C dp) and the -30 °C dp process atmosphere
resulted in the highest concentration of Mn at the surface. The predominant oxide
morphology observed at the surface of the two high Al- low Si steels comprised filmtype
oxides or irregular shaped nodules whereas the two high Si steels had an oxide
morphology that generally comprised spherical cap shaped nodules.

Good wetting was obtained for all alloys when using two low oxygen partial
pressure process atmospheres (-53 °C dp or -50 °C dp and -30 °C dp) and poor wetting
was obtained for a higher oxygen partial pressure process atmosphere ( +5 °C dp ). At the
+5 °C dp a considerably larger percentage bare area in the galvanized coating was
obtained for the two high Si steels when compared to the two high Al- low Si steels. For
the two high Si steels poor wetting at the +5 °C dp was attributed to the oxide
morphology with closely spaced Mn-Si oxide nodules being observed at the surface ofthese steels. For the 1.5% Al steel and 1.0% Al - 0.5% Si steel the poor wetting was due
to thick localized MnO films at the steel surface.

Despite selective oxidation observed at the surface for the -53 °C dp or -50 °C dp
and -30 °C dp process atmospheres good reactive wetting was observed. For these
processing conditions a number ofreactive wetting mechanisms were identified. When
oxides remained at the steel/coating interface, the oxides could be bridged by the Zn
overlay, Fe2Al5Znx or Fe-Zn intermetallics. Good wetting was also attributed to
aluminothermic reduction of surface oxides by the dissolved Al in the Zn bath. For
some processing parameters cracking of the oxide as a result of thermal stresses in the
oxide imposed during cooling from the intercritical annealing temperature to the Zn bath
temperature allowed the bath metal to reach the steel substrate, thereby improving
wetting. Similarly, liquid infiltration of bath metal at the oxide/steel grain boundaries
also contributed to good wetting on some samples. Lastly, in some cases wetting of the
oxide was observed.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Chemical and Biochemical Aspects of Nitroarene Mutagenicity

contributor:
McCarry, B. E.
Chemistry

subject: chemical, biochemical, aspects, nitroarene, mutagenicity, molecular

abstract:
 Nitroarenes are the nitro-functionalized derivatives of polycyclic aromatic hydrocarbons (PAH) which are found in a variety of environmental matrices, and are potential human carcinogens. The 1997 discovery of a potent mutagen, 3-nitrobenzanthrone, in diesel exhaust has renewed interest in these compounds. Theoretically- and experimentally-determined characteristics of nitroarenes have been explored as predictors of their mutagenic potencies in the Ames reversion assay. In this multifaceted project, the relationships of these parameters and rates of nitroarene metabolism to the mutagenic potencies of 11 nitroarenes in Salmonella typhimurium strain YG1021 were explored.

 Ab initio calculations at the HF/3-21G level were performed for these molecules. Calculated NO2 dihedral angles and εLUMO values were smaller in magnitude than those previously determined by lower quality semi-empirical and STO-3G ab initio calculations, and showed poor correlations with nitroarene mutagenicity. Molecular negative electrostatic potential surfaces for the nitroarenes studied possessed two regions which, when placed in a common orientation in 3-dimensional space, suggested specific binding contacts within the active site of the nitroarene-activating enzyme nitroreductase.

 An efficient GC-MS method was developed for the analysis of organic extracts from Salmonella incubations with nitroarenes in the determination of relative rates of metabolism, and employed a two-stage solid phase extraction sample clean-up scheme. The rates of nitroarene metabolism for six nitroarenes, whose mutagenic potencies ranged over two orders of magnitude, ranged from 450 to 3600 pmol/hr/mL Salmonella culture at 25°C and showed a good correlation with mutagenicity.

 The results of this work suggest that mutagenic potency is a direct result of intermediate accumulation, and cast serious doubts on the reported correlations between nitroarene physicochemical properties and mutagenic potencies. This study underscores the need for the in-depth examination of the characteristics of nitroarene intermediates as an explanation of nitroarene mutagenic potencies.

abstract: Thesis

abstract: Master of Science (MSc)


title: Separation and Characterization of Thia-Arenes and High Mass Polycyclic Aromatic Hydrocarbons in Coal Tar

subject: separation, characterization, thia-arenes, high mass, polycyclic, aromatic, hydrocarbons, coal tar

abstract:
 Coal tar is a rich source of polycyclic aromatic compounds (PAC) which include
hydrocarbons (PAH), sulfur-containing aromatics (PASH), nitrogen-containing aromatics
and high molecular mass PAH. The separation of coal tar into four fractions was carried out
on activated (170°C, 48 hrs) neutral alumina. Low mass aromatics and aliphatics were
eluted with hexane in fraction A1 (2.2% recovery), while PAH/PASH were eluted by
benzene in fraction A2 (25%). High molecular mass PAH were eluted by dichloromethane
in fraction A3 (5.5%) and nitrogen-containing aromatics were eluted by methanol in fraction
A4 (21%). These fractions were characterized by normal phase liquid chromatography, GCMS, probe mass spectrometry (for fractions A3 and A4) and LC-MS (for fraction A3).

 While ratio of PASH to PAH in fraction A2 was rather unfavorable (25:1), the separation of PASH from PAH was attempted using two methods: an oxidation/reduction method and a ligand exchange method. The oxidation/reduction method of Lee was a complete failure. The PdCl2-silica method of Nishioka was partially successful. Of the 25 thia-arenes identified in fraction A2, 12 eluted with the PAH while the other 13 were either partially (5) or fully (8) retained by the PdCl2-silica gel column and then eluted later to give a sulfur-enriched fraction. This fraction was further separated using normal phase HPLC to afford sulfur-containing compounds with molecular masses between 184 amu and 258 amu which exhibited almost no contamination due to PAH. Thus, it would be possible to purify about one-half of the PASH from a complex mixture such as coal tar.

 Fraction A3 which contained high mass PAH was subjected to semi-preparative normal phase HPLC to afford several high molecular mass PAH fractions. The 326 amu PAH fraction was selected because it contributed to 10% of the genotoxic of the mixture. This fraction was further separated by normal phase HPLC and the subfractions were analyzed by reversed-phase HPLC with diode-array detection. Thirty-five peaks were collected from the reversed-phase HPLC analysis and were characterized by probe mass spectrometry and fluorescence spectroscopy (in part). Of the 35 peaks, 8 peaks were eluted in the mutagenic active range; these eight compounds will be evaluated using the Ames assay to determine which are active mutagens.

abstract: Thesis

abstract: Master of Science (MSc)


title: An Investigation of the Commercial Applications of Acrylamide Based Water Soluble Polymers

contributor:
Hamielec, A. E.
Chemical Engineering

subject: investigation, commercial, applications, acrylamide, water, soluble, polymers, cationic

abstract:
 In part I of this dissertation, several cationic polyacrylamides were tested under different conditions for their ability to improve the retention of fines in papermaking. A dynamic drainage jar was used to simulate the turbulence encountered in the papermaking process. Several factors, including temperature, the amount and intensity of turbulence, the additive concentration and the presence of impurities were found to affect fines retention with polymers present. A polymer made by Nalco Chemicals proved to be superior to a commonly used polymer, Percol 292 for a standard fine paper pulp. It was thought that further retention improvements might be possible by tailoring the charge density and molecular weight of polyacylamide retention aides for the specific papermaking system they are intended for. Novel approaches to retention such as those employing combinations of an anionic polymer, a cationic polymer and zirconium oxychloride were thought to show promise as well.

 In part II of this dissertation several broad polyacrylamide molecular weight standards were prepared by inverse suspension and solution processes on pilot plant equipment at the McMaster Institute for Polymer Production Technology. They were characterized by laser light scattering and viscometry at McMaster, and externally by other methods. Although the polyacrylamides prepared compare favourably to currently available commercial standards when both are analysed by SEC, further analysis must be done to be certain of the molecular weight averages.

 A relationship is presented to provide for simpler and more accurate light scattering analysis in the future. This relationship relating Mw to the second Virial coefficient may be used to eliminate some uncertainty in the often scattered plots encountered when calculating molecular weights for polyacrylamides analysed by light scattering.

abstract: Thesis

abstract: Master of Engineering (MEngr)


contributor:
O'Brien, Susie
English and Cultural Studies

abstract: Title: The Nature of Capitalism: How Green Can We Grow?, Author: Michael Mikulak, Location: Mills

abstract:
What does it mean to live sustainably? This dissertation considers the history of Western
environmentalism in terms of antagonism and convergence with capitalism. Whereas
many forms of environmentalism have been critical of capitalism and focused on
production, contemporary forms of mainstream environmental discourses are now largely
focused on reforming consumption. The dissertation considers how the greening of
capitalism, as an attempt to account for the environmental crisis within the framework of
neoliberalism, is interfacing with various movements focused on producing alternatives.

To this end, the dissertation focuses on alternative food movements as participating in the
struggle for reimagining the current relationship between nature, culture, and the
economy. Chapter One considers the significance of utilizing economic language in
support of environmental reforms. It traces some dominant narratives of capitalism and
nature and by utilizing discourse analysis, examines how the environmental crisis is
being framed. By focusing on questions of representation, Chapter One demonstrate that
conceiving ecological degradation as an economic opportunity has very profound
material consequences, some of which are positive and some of which are negative.

Chapter Two contextualizes the argument by consider the politics of food, focusing in
particular on the stories we tell about it, and examining how food is becoming a potent
site for both resisting and reinforcing capitalist value practices. It examines the discourses
of ethical consumption, pastoralism, utopia, and dystopia in a consideration of how a
politics of the everyday is complicated by economic arguments.

Chapter Three moves from narrative to practice by considering how the autobiographical
focus of food narratives can participate in the creation of new value systems. By focusing
on the author's own experiences with the 100-Mile diet, this chapter examines the role of
enchantment and technologies of self in producing forms of ecological subjectivity that
can challenge capitalism.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Model for Characterizing Rheological Behaviour of Fresh Mortar and Conrete

abstract: Title: Model for Characterizing Rheological Behaviour of Fresh Mortar and Concrete, Author: Fathollah Mahmoodzadeh, Location: Mills

abstract:
Rheology of fresh mortar and concrete affects the flow of the mixture as well as the corresponding rheological properties. The rheological properties, in tum, are known to affect the placement and workability of the fresh mixture, and therefore can be used to control the quality of the fresh material and the properties of the hardened material. Accordingly, constitutive equations for fresh mortar and fresh concrete were developed to characterize the mixture flow and quantify the rheological properties. Moreover, by incorporating the mixture composition into the constitutive model, one can provide the concrete industry with the necessary tools to design and control the quality of concrete.

This study presents a constitutive material model for mortar and concrete that employs the cell method and builds on the work of Gang et al. It postulates that the shear stress is the sum of three components: static interaction between particles, dynamic interaction between particles, and collision ofparticles, and that the cell is a representative volume of mixture. For fresh concrete, the effects of particles collision are considered negligible due to high particles concentration, and the resultant constitutive equations become the Bingham model.

Two new models were developed to quantify the rheological properties of fresh concrete, namely plastic viscosity and yield stress. The plastic viscosity model postulates that the cell is a representative volume and that the packing density of the mixture can be used to characterize the aggregate's geometric and physical properties. The model is then extended, to model yield stress following the analogy concept. Evaluation of the proposed models was carried out by comparing their predictive capabilities to experimental data as well as to results of rheological models proposed in the literature. Results revealed that the proposed models provide a higher degree of correlation to the experimental data as well as a more consistent and reliable predictions in comparison to the models currently proposed in the literature for concrete and/or dense suspensions.

The proposed constitutive equations for fresh mortar were also evaluated using experimental data reported in the literature. The results are found to compare very well and that the difference is within the measurement errors.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Contemporary Healing Work: a Social Worlds Analysis of Reiki in Practice

contributor:
Bourgeault, I. L.
Sociology

abstract: Title: Contemporary Healing Work: A Social Worlds Analysis of Reiki in Practice, Author: Yvonne L. V. LeBlanc, Location: Mills

abstract: This dissertation examined the social history and organizational structure of Reiki (raykey) and explored the shared ideology and intersecting involvements of fifty practitioners who are engaged in this form of energy healing work. Through a social worlds analysis I illustrate how the central process of segmentation is influencing this social world. My research reveals that Reiki is a heterogeneous set of practices with a diffuse organizational structure. Practitioners hold mixed allegiances to varying traditions and schools of practice and often develop their own unique working styles. Through their discovery of Reiki, practitioners choose to make a commitment to a twin or conjoined practice; that is, to both self healing and to the healing facilitation of others. In this dispersive and differentiated world participants developed a shared therapeutic ideology. This encompasses a core 'energetic world view' coupled with common values that include qualities of virtue, fulfillment, and respect for tacit knowledge. This therapeutic ideology buttresses personal creativity and diversity amongst practitioners. I also found that practitioners confront a continuum of public acceptance or social approval for their work that shifts from hostility to receptivity. For practitioners, although managing public acceptance was largely about defending their social world, it was also about maximizing opportunities to increase public awareness and about creating bridging opportunities that expand the boundaries of Reiki in other social world segments. This study is unique in the sociology of CAM because it offers an in-depth look at the practice of Reiki. It provides a novel sociological analysis of the processes and interactions that form, shape, and direct a contemporary healing practice. My study contributes to social worlds theory by foregrounding the salience of the actions, interactions, and experiences of front-line practitioners engaged in this community of practice.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Nonlinear Feedback Equalization of Digital Signals Transmitted Over Dispersive Channels

contributor:
Gladwin, A. S.
Electrical Engineering

subject: nonlinear, feedback, equalization, digital, signals, transmitted, dispersive, channels, pulse

abstract:
 This thesis deals with the problem of digital communication over noisy dispersive channels. The dispersion causes the overlapping of successive received pulses thus creating intersymbol interference which severely limits the performance of conventional receivers designed to combat only additive interference or noise.

 In this thesis Bayes estimation theory has been applied to obtain a new, optimum, unrealizable receiver structure for the improved reception of noisy, dispersed, pulse amplitude-modulated (PAM) signals. By making certain approximations, a realization of this structure, known as the estimate feedback receiver or equalizer, is obtained. It consists of the combination of a matched filter and a nonlinear, recursive equalizer having, in the case of binary signals, a hyperbolic tangent nonlinearity in the feedback path. The well known decision feedback equalizer is shown to be a small noise limiting case of the estimate feedback equalizer. A saturating limiter is also considered as an approximation to the hyperbolic tangent nonlinearity.

 A new adaptive algorithm for the iterative adjustment of the estimate feedback equalizer is derived. It incorporates an extrapolation process which has the purposes of accelerating convergence of the equalizer's parameters to their optimum values and of maintaining the equalizer's frame of reference. It is constrained so that the equalizers parameters always move toward their optimum values.

 Computer simulations are used to demonstrate the properties of the adaptive estimate feedback equalizer and to compare them to those of presently known equalizers. When the estimate feedback equalizer is used, without a matched filter preceding it, to equalize phase distorted channels, its performance is seen to be superior to that of existing equalizers. The performance of an equalizer using a saturating limiter in place of the optimum hyperbolic tangent nonlinearity is seen to be almost as good as that of the estimate feedback equalizer.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Modeling of Scrap Heating by Burners

contributor:
Irons, Gordon A.
Materials Science and Engineering

abstract: Title: Modeling of Scrap Heating by Burners, Author: Mamalesh Mandal, Location: Mills

abstract:
The efficiency and productivity of Electric Arc Furnace steelmaking has improved with a number of new technologies. One of these is the use of oxy-fuel burners to assist the electric heating. Initially burners were just used to melt the scrap at the slag door where arc heating is inefficient. At present virtually all modern EAF use oxy-fuels burners to decrease electric energy consumption and increase productivity. Despite the impressive performance of these burners there is little information on the efficiency of the heat transfer between the combustion gas and the steel scrap in the furnace. The purpose of this research was to measure and model the heating efficiency for a range of scrap types. The ultimate goal of this study is to assist operators with the selection of energy inputs and scrap grades from different sources, so as to optimize the operation.

Experimentally, steel scrap heating phenomena were studied using an oxy-fuel burner in a small scale furnace (1m3) for a range of burner power, scrap type and furnace configuration.

An in-house computer model was developed, considering non-uniform porosity inside the furnace, turbulence, dynamic behavior of porosity due to localized melting. The model was tuned using the experimental data of scrap heating by oxy-fuel burners in a small-scale furnace (1 m3). Due to lack of literature of porous media fluid flow and heat transfer for irregular shaped particles and complexity of the problem a detail analysis and considerations of the model parameters e.g., porosity variation inside the furnace, permeability of the bed, drag coefficient of the bed, effective thermal conductivity of the bed, fluid to solid heat transfer coefficient and radiation inside the bed, were performed. Model parameters were dependent upon porosity of the bed and characteristic particle diameter. Sensitivity analysis was performed to study the effectiveness of heating with model parameters. Measured porosity variations were used for numerical simulation and characteristic particle diameter for different scrap was tuned to match the experimental results with numerical simulation. Thermocouple temperatures were also modeled since it was between the gas and solid temperatures. Using tuned characteristic particle diameter simulations were performed for different scrap with different furnace configuration.

Experimental and numerical modeling results were used to analyze heat transfer and fluid flow phenomena during scrap heating by burners. This appears to be the first time a numerical model for heat transfer between flame and scrap was developed and validated with experimental data.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Prediction of Income on Peasant Farms in Andean Ecuador

contributor:
Wood, H. A.
Geography

subject: prediction, income, peasant, farms, Andean, Ecuador

abstract:
 It is the purpose of this study to determine empirically the contribution of a set of variables to the observed variation in income per hectare on 100 peasant farms in Ecuador. Specific consideration will be given to the relationship between farm size and farm productivity.

 Twenty-four characteristics were chosen to describe the structure of peasant agriculture. An examination of the distribution of each characteristic over the 100 farms illustrated the heterogeneous nature of the farm sample. Regression analysis applied to the sample at the aggregate level yielded poor results. Large amounts of variability in the dependent variable remained unexplained, and the standard error of the estimate was relatively large in comparison to the observed mean value of the dependent variable. The model was improved when the sample was disaggregated by region, although the standard error remained high which greatly weakened the potential of the model as a predictor equation.

 To increase the power of the regression model, and to more effectively
analyse the significance of the set of variables to variation in farm income, it was decided to type the farms using factor analysis.

 Principal axes factor analysis was performed on the matrix of correlation coefficients for the twenty-four standardized characteristics. The factors were then rotated using varimax rotation to obtain a more simplified loading matrix. Eight primary factors were produced which together accounted for 62.25 percent of the variance in the original matrix. Ward's hierarchical grouping algorithm was then applied to the matrix of factor scores for the principal eight factors, and a classification containing fourteen types of farming activity was produced.

 The relationship between income and farm size was then reconsidered by farming type. There was a slight improvement in the power of the model applied to farm type although the amount of explained variability remained small. Simple regression of income per hectare on farm size, then, failed to explain a large proportion of the variance in the dependent variable even when the sample was considered by farming type.

 In order to reduce the measure of 'non-explained' variability in
the dependent variable, and to increase the potential of the regression model as a predictor equation, income per hectare was regressed on the rotated factors. Multiple step-wise regression was performed on (a) the complete sample, (b) the sample disaggregated by region, and (c) two major farming types. The multiple step-wise regression model greatly
increased the amount of explained variability in the dependent variable and indicated the significance of the contribution of each independent variable to variation in income per hectare on the farms.
The study is presented in five parts:
Chapter 1 introduces the problem to be analysed.
Chapter II presents the data base, and a simple linear regression analysis examines the relationship between income and farm size on the 100 farms. The results of the regression performed on the aggregate level are poor. The analysis is then repeated on the sample disaggregated by region. The power of the model is greatly increased when the sample is divided into regional subsets, but large amounts of variability are left unexplained and the standard error of the estimate remains high.

 Chapter III groups the 100 farms according to a typology based on an analysis of the structural and economic organization of the farming unit. A correlation analysis is performed on the twenty-four characteristics and simple correlations between the data are considered. Factor analysis is then performed on the matrix of correlations, and the major dimensions of variation in the data are enumerated. Finally, a grouping algorithm is applied to the matrix of factor scores on the principal factors, and a classification of the farms is produced.

 Chapter IV reconsiders the relationship between income and farm size by farming type. Multiple step-wise regression then examines the contribution of a set of variables to variation in income per hectare.

 Chapter V summarizes the merits and weakness in the methodological approach of the study and enumerates the major findings of the analysis.

abstract: Thesis

abstract: Master of Arts (MA)


title: Synthesis, Structure and Optical Properties of β- and β"-Gallates

contributor:
Nicholson, P. S.
Materials Science and Engineering

subject: synthesis, structure, optical, properties, gallates, oxygen, formation, ion-exchanged, luminescence

abstract:
 β- and β"-gallates are analogs of β-Al2O3 family. K-β"-gallate was directly synthesized via solid state reaction with β-Ga2O3 (β-gallia) precursor. When α-Ga2O3 is used as starting material, K-β-gallate forms in spite of incorporation of aliovalent ions, i.e., Li+, Zn2+ and Cd2+. It is suggested that oxygen packing sequence in the Ga2O3 precursor plays an important role on the formation of K-β- or β"- gallates. β-Ga2O3 has the ABCABC oxygen packing sequence, similar to β"-gallate structure, thus β-Ga2O3 leads to form pure K-β"-gallate; α-Ga2O3 has the hexagonal structure with ABAB oxygen packing sequence. K-β-gallate forms around the α-Ga2O3 --> β-Ga2O3 phase transformation (≈700°C). This low reaction temperature negates the aliovalent ions to stabilize β"-structure when α-Ga2O3 precursor is employed.

 K-β- or β"-gallates show good ionic conductivity. Both can be fully ion-exchanged with Ba2+ and Sr2+. Sr-β-gallate is metastable and transforms to magnetoplumbite structure after annealing at 1200°C. But Ion-exchanged Ba-β-gallate is stable. Zn2+ doped Ba-β-gallate can be directly formed at 1300°C via solid state reaction.

 Mn2+ ion-exchanged K-β-or β"-gallates exhibit green photo luminescence. Mn2+ can also locate in the spinel block to confer green photo luminescence. Eu3+, Ce3+ and Eu2+ can not be ion-exchanged into the conduction plane of K-β-gallate. There is no luminescence observed for directly synthesized BaZnGa10O17 doped with Eu3+, Ce3+ and Eu2+ due to photoionization effect. When half Ga3+ is substituted by Al3+, directly formed BaZnAl5Ga5O17: Eu3+ shows red emission upon UV excitation (254nm). Blue emission of 485nm wavelength was observed for BaZnAl5Ga5O17: Eu2+.

 The structure of β- or β"-gallates was refined by Rietveld neutron powder diffraction. Zn2+ was detected on the Ga(2) site in β-K1.64Ga10.36Zn0.64O17. Extra K+ is balanced by Zn2+. K+ is distributed between BR (2(c)) and MO (6(h)) sites. Ba2+ was detected at MO sites, slightly shift from the BR sites in β-BaZnGa10O17. Extra K+ is also compensated by Zn2+ in β"-K1.67Ga10.33Zn0.67O17. In undoped K-β-gallate, VGa(1)Ga(5)i is introduced to balance extra K+. Extra K+ in undoped K-β"-gallate is supposed to be balanced by the formation of Ga+.

abstract: Thesis

abstract: Master of Engineering (MEngr)


contributor:
MacGregor, John F.
Mhaskar, Prashant
Chemical Engineering

abstract: Title: System Identification and Trajectory Tracking Control and Batch Processes Using Latent Variable Models, Author: Masoud Golshan, Location: Mills

abstract:
This thesis considers the problem of model identification and trajectory tracking control in batch processes. From the point ofview of a control engineer, finite duration of the process, not operating around the equilibrium point, and time-varying operating conditions with nonlinear behavior are amongst the most significant differences between batch and continuous processes. The major contribution of this thesis is to develop an alternative to Nonlinear Model Predictive Control (NMPC) by incorporating Latent Variable Models (LVMs) in the course of an MPC algorithm (called LV-MPC).

Two control formulations are developed in this study: Control in the latent variable space and control in the original variable space. The algorithms are based on multi-phase PCA models developed on batch data arrays. In both cases prediction of the future trajectories is accomplished using statistical latent variable missing data imputation methods. It is shown that the two control formulations are complementary to each other. The control in the latent space is the infinite horizon L V-MPC, while the control in the original variable space is the finite horizon LV-MPC. The proposed LV-MPCs can handle constraints. The methods are tested on two simulated batch reactor case studies.

Furthermore, different latent variable modeling alternatives for modeling of batch processes are investigated from the view point of their application in the course of L VMPC. Two modeling alternatives previously proposed in the literature are incorporated in the course of the L V-MPC methodology: Batch-Wise Unfolding (BWU), and Observation-Wise with Time-lag Unfolding (OWTU). The BWU modeling approach addresses the nonlinearity and time varying properties of the batch process. However, it needs a large number of batch runs in the training dataset. The OWTU approach leads to a Linear Time Invariant (L TI) modeling of the process which captures the average process dynamics. However, it needs only 1-3 batch runs for building the process model which makes this approach attractive for practical situations. In addition, a new modeling approach is proposed in this study which tries to capture the major benefits ofboth BWU and OWTU while avoiding the drawbacks of each one. It is called the Regularized BatchWise Unfolding (RBWU) modeling approach. This modeling approach has the capability of modeling the nonlinearity and time-varying properties almost as accurately as BWU
and at the same time it leads to a smoother PCA model and needs fewer numbers of observations for building the model as compared to BWU. The performances of the three latent variable modeling approaches in the course of LV-MPC for trajectory tracking are illustrated using two simulated batch reactor case studies. Recommendations are then given on which modeling approach to use under different scenarios.

In the last stage of this research, various issues on the closed-loop identification of empirical latent variable models for model predictive control (MPC) of batch processes are investigated. It is shown that in most cases, it is possible to identify the batch process models only from historical batches without the need for external excitation of the closed-loop system by dither signal on top of the controller output. The maximum requirement would be to use extra batch runs with different set-point trajectories in the training dataset. The issue of model bias in closed-loop identification is investigated and the desirable controller characteristics to be used in the data generation step to minimize this bias in the latent variable models are discussed.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Waddington, J. M.
Geography and Earth Sciences

abstract: Title: Hydrological and Biogeochemical Controls on Calcareous Fen Ecosystems, Author: Timothy P. Duval, Location: Mills

abstract: Calcareous fens are base cation-rich peatland ecosystems that support a diverse assemblage of vegetation. This study furthers our knowledge on these unique wetlands through the determination of the hydrological and biogeochemical processes governing calcareous fen ecosystem function. The growing season hydroperiod of three calcareous fens in close proximity to one another was found to be very different: some streamside locations \Vere subject to water table fluctuations ofjust 10 cm. whereas other sites to > 1 rn fluctuation. Only a small area of the three fens was subject to appreciable groundwater upwelling. contradicting previously held concepts. The Riparian Fen derived most of its \Yater from the stream: with groundwater recharge and stream discharge the principal outlets. The Trough Fen was precipitation and evapotranspiration dominated. with moderate overhank flooding. and small groundwater discharge. The Basin Fen received half of its growing season water through groundwater discharge. with most water leaving through cvapotranspiration. The subsurface flowpath direction and magnitude were variable among the calcareous fens and were subject to between-year flow reversals. Phosphorus was very limiting across most of the fen areas. and this was principally related to an association with calcium and magnesium in the fen_pore-waters. Gradients of redox-sensitive solutes were detected at all sites. and were organized along the dominant hydrological flowpaths. Plant species richness and diversity within the calcareous fens \Vere controlled by differential responses of individual species to in situ hydrological and biogeochemical gradients. Organic matter content in the surface peat and the duratfon of the initial saturation period to start the growing season proved to be the most useful metrics for determining plant species ranges/tolerances within the calcareous fens.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Deen, Jamal
Electrical and Computer Engineering

abstract: Title: CMOS Imagers for Low-Level Light and Highspeed, Author: Munir M. El-Desouki, Location: Mills

abstract:
Fluorescence optical imaging is becoming a very important technique for in vivo imaging and characterization of biological tissues. In order to add more contrast to the fluorescence image, fluorescence life-time imaging (FLIM) can be used, making it possible to differentiate between molecules with overlapping spectra, such as cancerous and noncancerous cells. However, designing FLIM imaging systems in a compact, complete camera-on-chip solution is a very challenging task and has led to significant research efforts in designing high-speed and high sensitivity imagers.

This work focuses on designing low-light level imagers in CMOS technology for biomedical applications that can be suitable for extremely high-speed imaging applications, such as FLIM. A fully integrated, 256-pixel CMOS camera-on-chip, was fabricated in a standard CMOS 0.18 μm technology. The imager was tested by controlling it with an Altera FPGA board. When clocking the ADC at a frequency of 1 MHz, images were obtained at about 60 frames/s. The design was next improved to achieve ultrahigh-speed imaging using a CMOS imager that can capture 8 frames with a frame capture rate that is higher than 1.25 billion frames per second.

The sensitivity was further improved using avalanche photodiode single-photon counters that were implemented in a standard digital 130 nm CMOS technology. The circuit achieves deadtimes as low as 200 ps, which is at least an order of magnitude less than previous work. The circuit also has a higher fill-factor of 25%, compared to 1-5% in previous work. A novel deadtime reduction technique design for active quench and reset circuits is also discussed.

The dynamic range of the imager was also improved using a novel design that relies on single-photon counting in time-domain. The design can achieve high sensitivity and high dynamic range, while maintaining a speed that is around I 000 times faster than conventional time-domain imagers. In order to further improve the frame rate, an imager that allows for simultaneous pixel counting and threshold detection in time-domain was also designed. The pixel also includes a novel analog counting technique that allows for an increased fill-factor.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Study Towards the Total Analysis of Stretford Liquors Using HPLC Techniques

subject: Stretford, liquors, HPLC, techniques, analysis, polymer, ion exchange

abstract:
 The ultimate objective of this research project was to establish an HPLC method that allows the quantification of most of the major components of a circulating Stretford process liquor using one sample. The criteria that had to be met were reasonable retention times, resolution approaching 1.0 and quantitative results (ie. with an uncertainty in the accuracy and precision of the results less than ± 10%). Ion chromatography was the route chosen since the major components of the circulating liquors are present as either inorganic or organic anions. Ion pair chromatography and ion exchange chromatography were the general methodologies investigated during the study.

 Ion pair chromatography, specifically soap chromatography, was successful in the isolation of the NaSCN, Na2SO4 and Na2S2O3 species of the circulating Stretford liquors. It was unsuccessful in the quantitative separation of these species. The method was abandoned in order to find a method which could quantify these species as well as the other components of the circulating liquors.

 The ion exchange chromatography studies fell into two categories, that being columns with a silica based packing and columns with a polymer based packing. The silica based columns had a limited operating range of pH for the analysis and the backbone of these columns degraded at pH values exceeding pH 5.5. The polymer based ion exchange columns had a much wider operating pH range and allowed for the analysis of the Stretford liquors without the need to change the pH of the solution.

 The best possible method of analysis was the polymer based technique. All of the components of the Stretford liquors, with the exception of the ADA (anthraquinone disulfonic acid) could be quantified in under 15 minutes. The method provided quantitative results and very good resolution between the species eluted.

abstract: Thesis

abstract: Master of Science (MSc)


contributor:
Botton, Gianluigi A.
Materials Science and Engineering

abstract: Title: TEM Investigations on Bismuth-Based Perovskite Oxides, Author: Lina Gunawan, Location: Mills

abstract:
The research presented in this thesis aims to provide fundamental understanding
about the structure-property relationships in Bi-based perovskite oxides from the
nanoscale to the atomic level so that the properties of these materials can eventually be
tuned. This study focused on the investigations of structure and ordering phenomena
in several Bi-based compounds, namely a combination of BiFe03 (BFO) and BiCr03
(BCO) as well as a layered perovskite Bi4_xLax Ti30 12 (x = 0.75) (BLT), using a variety
of transmission electron microscopy (TEM) techniques. The performance of the new
generation of spherical aberration (Cs)-corrected TEMs with sub-A spatial resolution
was also demonstrated.

The investigations were performed using both conventional TEMs as well as the entirely
new generation TEMs (based on aberration correction) as the major characterization
instruments. Aberration-corrected TEMs were specifically utilized for analysis
at the atomic level, the observation of the structure of defects and probing of valence
changes. The importance and advantages of using a Cs-corrector in improving spatial
resolution for observations of atomic structure were reviewed in detail.

First, the Bi-based perovskite oxide films of BbFeCr06 (BFCO 1/1), consisting of
BFO and BCO with a 1:1 ratio and epitaxially grown by the pulsed laser deposition
(PLD) technique, were investigated in order to understand the remarkable increase in
saturation magnetization. The selected area electron diffraction (SAED) and convergent
beam electron diffraction ( CBED) experiments revealed various weak reflections,
which were explained through systematic elimination of several possible factors. The
extra weak reflections in the CBED pattern of the sample oriented with the zone axis
<110> arose due to B-site cationic ordering and anti-phase tilting of B06 octahedra.

Other weak reflections in the CBED pattern acquired at an orientation parallel to the
<100> zone axis correspond to the reflections of a secondary phase, Bi20 3 , which was
formed during the deposition of the film. Electron energy loss spectroscopy (EELS)
experiments revealed that both B-site cations, i.e., Fe and Cr, possess the same valence
of 3+.

Second, the oxide films produced by the co-deposition of BFO and BCO in a 1:3 ratio,
BbFe0.5Crl.506 (BFCO 1/3), were investigated to study the predicted B-site cationic
ordering. Through high angle annular dark field (HAADF) imaging, our results revealed
a structure that is different from the double perovskite structure previously
expected. The two-dimensional XRD experimental results gave a 3D reciprocal space
map, which showed patterns consistent with the SAED patterns and revealed the
presence of twinning and variation of in-plane orientations in the film. A modified
Ruddlesden-Popper (RP) structure, which closely resembles the atomic structure in
the HAADF images, was proposed as an alternate structure for the new model of the
BFCO 1/3 unit cell. The refinement of the XRD I-20 result on the BFCO 1/3 film
gives a monoclinic unit cell (space group #14, P 2i/n) with lattice parameters of a =
10.9764 A, b = 10.8479 A, and c = 15.9073 A, with a= I= 90° and /3 = 90.3°. The
agreement between the simulated and the experimental SAED patterns, however, was
limited to the major reflections only.

The last investigated oxide is a well known layered perovskite oxide Bi4_xLax Ti30 12 (x
= 0.75), BLT, a candidate material likely to replace lead-based ferroelectric materials
in various non-volatile memory devices. The TEM investigations focused on the study
of the location of the La dopants in the Bi4 Th012 (BiT) parent unit cell so as to
provide new information on the good fatigue resistance of BLT. Through HAADF
imaging, we showed the presence of translational defects, out-of-phase boundaries
(OPBs), which originate from the film-substrate interface. The EELS maps revealed
that La ions are most likely to occupy the top part of the Bb02 layer in the BiT parent
unit cell structure, instead of the perovskite-like layer. The preferential location of La
dopants in the BiT unit cell and the presence of OPBs within the films are discussed
in terms of the mechanism of the good fatigue resistance of BLT.

In summary, the TEM investigations on several Bi-based perovskite oxides give insights
on various structures and defects at atomic scale, which contribute to further understanding of their physical properties. Throughout the study, the use of aberrationcorrectors
has demonstrated significant improvement in the quality of TEM imaging
and analyses, revealing atomic scale information which was previously unattainable
with conventional TEMs.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Surface Segregation and Initial Stages of Oxidation on Ni-Co Alloys

contributor:
Dawson, P. T.
Smeltzer, W. W.
Underhill, P. R.
Materials Science

subject: surface, segregation, initial stages, oxidation, Ni-Co, Alloys, atomic

abstract:
 This thesis consists of studies carried out on the Nickel-Cobalt alloy system. The surface segregation behaviour has been studied over the range of composition from 14 to 90 atomic percent Nickel using Auger Electron Spectroscopy (AES). An analysis procedure has been developed that is based on computer simulation of observed spectra using pure metal standard spectra and has resulted in excellent matches. Nickel has been observed to segregate over the entire range of compositions studied and the driving force for segregation has been investigated by monitoring the equilibrium surface composition over a range of temperatures from 813 to 1100 K. The enthalpy and entropy of segregation has been determined on single grains of orientations (111) and (210) in a sample of composition
56.0 atomic percent Nickel as well as on the (111), (100) and (110) faces of a 50.0 atomic percent Nickel single crystal.

 The initial stage of oxidation has also been studied here using Scanning Auger Mapping and digital image processing. The initial stage of oxidation carried out in-situ has been shown to proceed via an island nucleation and growth mechanism which has been confirmed by imaging islands based on the oxygen Auger signal. A preliminary study of the effects of temperature and pressure on the island growth stage of oxidation has been completed and results are reported.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Hranilovic, Steve
Electrical and Computer Engineering

abstract: Title: Modulation and Detection in Wireless Optical Channels Using Temporal and Spatial Degrees of Freedom, Author: Mohamed D. A. Mohamed, Location: Mills

abstract:
Most wireless optica.l modems are able to modulate and detect only the intensity of
tho optical carrier. As a result, conventional techniques, designed for radio frequency
communications, arc seldom efficient. This thesis designs new efficient modulation
and detection techniques for wireless optical communication systems that take into
consideration the characteristics and constraints of wireless optical channels.

Many degrees of freedom are available at the transmitter and the receiver in both
ternpora1 and spatial domains. The main theme of this thesis is to use such degrees
of freedom to achieve higher pO\ver/spectral efficiencies and simpler transceivers. A
new modulation technique, optical impulse modulation (OIM), is proposed for indoor
diffuse wireless infrared channels. Present-day laser diodes have higher pulse rates
than the channel bandwidth. OIM utilizes such extra temporal degrees of freedom to
satisfy the channel amplitude constraints, while the transmit data are confined to the
lowpass region that represents the channel passband. Another modulation technique,
halftoned spatial discrete m:ultitone (HSDMT) modulation, is proposed for indoor
multi-input/multi-output (MIMO) point-to-point wireless optical links. Current spatial
light modulators (SLMs) have higher spatial bandwidth than can be supported by
the spatially lowpass MIMO channel. Such bandwidth provides extra spatial degrees
of freedom that are employed by HSDMT modulation to decrease the transmitter complexity by considering binary-level SLMs. Finally, a novel detection technique
is proposed which employs the receiver spatial degrees of freedom to mitigate the
effects of atmospheric turbulence in outdoor free-space optical communications. By
using digital micromirror devices, the receiver optically computes linear projections
of the turbulence-degraded focal-plane signal distribution onto an orthogonal basis.
These projections are used to select the portions of the focal-plane which contain significant
energy for symbol detection. Performance improvements are quantified via
simulations for all the proposed techniques.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Concentration and Distribution of Boron in the Keweenawan Metabasalts of Mamainse Point, Ontario

contributor:
Shaw, Denis M.
Geology

subject: concentration, distribution, boron, Keweenawan, metabasalts, rock, magmatic fluids, crust

abstract:
 Nine rock samples from the mafic volcanics of Mamainse Point, Ontario were analysed for boron using Prompt Gamma Neutron Activation Analysis (PGNAA) and Alpha-Track Imaging (ATI). The mean concentration of boron in these rocks was 7.85 ppm with a maximum concentration of 15.5 ppm and a minimum concentration of 4.21 ppm. The Mamainse Point samples are therefore enriched in boron relative to fresh basalts (~ 2 ppm B) but depleted relative to basalts altered on the seafloor (30 - 60 ppm B). From ATI the boron was found to be most highly concentrated in iron oxides, chlorite, stilpnomelane and microscopic fractures throughout the rock. Plagioclase, clinopyroxene, quartz and calcite were all low in boron.

 These results led to the conclusion that the Mamainse Point Formation is of continental rather than marine origin. The addition of boron to the rock has resulted from penecontemporaneous burial and hydrothermal metamorphism in the zeolite and subgreenschist facies through the interaction of boron-bearing hydrothermal fluids. The source of the boron is thought to be from the surrounding Precambrian terrain (Canadian Shield), the lower continental crust and magmatic fluids associated with volcanism.

abstract: Thesis

abstract: Bachelor of Science (BSc)


title: INDIVIDUAL GROWTH TRAJECTORIES FOR PRETERM INFANTS

title: INDIVIDUAL REFERENCE GROWTH TRAJECTORIES FOR PRETERM INFANTS WITH POSTNATAL WEIGHT LOSS AND CONVERGENCE WITH TERM TRAJECTORIES OPTIMIZED TO MINIMIZE DISEASE RISK (DOHAD) - IMPLICATIONS FOR CALCULATION OF POSTNATAL GROWTH RATES IN CLINICAL PRACTICE

contributor:
Fusch, Christoph
Medical Sciences

subject: Growth Nutrition Preterm Infant Individual Trajectory

abstract:
BACKGROUND: The DoHAD hypothesis suggests that preterm infants should achieve similar growth and body composition to healthy term-born infants in order to minimize disease risk. Postnatal growth of preterm infants is not fully understood and requires additional characterization, particularly in terms of differences to and transition from intrauterine growth. The period of postnatal adaptation to extrauterine life has been described in preterm infants by Rochow et al., 2016 and was seen to last 21 days. During these first 21 days of life, preterm infants experience a physiological, one-time, permanent contraction of extracellular water spaces (water loss), which causes a downward shift in the growth trajectories. This period of adaptation/water loss and the transition to extrauterine growth rates to achieve WHOGS target trajectories need to be incorporated into individual reference curves for preterm infants.
OBJECTIVES: To develop and evaluate approaches to establish individualized growth trajectories for preterm infants to achieve growth similar to the WHO growth standards (WHOGS) for healthy infants at term, using recently published data about the physiological postnatal adaptation.
METHODS: Two approaches were compared: 1) Postnatal-Percentile Approach: growth following the percentile at day of life (DOL) 21 until term; 2) Growth-Velocity Approach: using day-specific Fenton median growth velocities between DOL 21 and term. The impact of these approaches were compared using body compositions of 57 healthy preterm infants obtained before discharge (36+0/7 to 42+6/7 weeks PMA).
The main outcome was the weight difference between the predicted trajectory and WHOGS target at 42+0/7 weeks PMA for the infants’ birth weight percentile.
RESULTS: Postnatal-Percentile Approach: Trajectories deviated by up to 930g and did not match with WHOGS. Growth-Velocity Approach: Trajectories converged with term WHOGS after adjusting growth velocities with a factor of 1.0017 (approximately 10% increase in daily growth velocities). The validation of the Growth-Velocity Approach in preterm infants with minimal medical interventions revealed little deviation between predicted and actual weights. Infants were symmetrically distributed around zero deviation with a mean deviation of -10±370g and an average of 20% fat mass. In contrast, the Postnatal-Percentile Approach showed large deviations between predicted and actual weights and a skewed distribution around zero deviation with a mean deviation of -310±380g or 70±350g, following the birth or DOL 21 percentile, respectively.
CONCLUSIONS: Individualized growth trajectories for preterm infants converged with the WHOGS when Fenton daily median growth velocities were applied and optimized with a single factor. The simplicity of the model and its ability to predict target weights that correspond to an appropriate fat mass suggests a biological principle. These results provide a superior understanding of preterm infant’s growth including the physiological postnatal adaptation and new trajectories to achieve WHOGS target trajectories. Results can be used to develop a bedside tool to aid clinicians in monitoring growth, guiding nutrition and preventing chronic adult diseases as a consequence of unguided, inappropriate growth.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: It has been well established that growth of preterm infants has a long-term impact on health in adulthood. Since the survivability of preterm infants has drastically improved in the last decades, there has been a shift in focus to improving quality of life, including improved growth. Infants that grow too quickly or too slowly may develop inappropriate body compositions, with either too much or too little fat. A sub-optimal body composition can put infants at an increased risk for developing cardiovascular, metabolic or neurodevelopmental diseases later in life. In order to prevent these diseases and optimize growth, it is necessary to have a better understanding of how preterm infants should grow. This thesis aims to improve the characterization of growth for preterm infants by providing individual reference growth trajectories for preterm infants that take into consideration postnatal adaptation and aim to minimize later disease risk.


contributor:
Razaqpur, A. G.
Civil Engineering

abstract: Title: A Novel FRP Anchor for Preventing Delamination in FRP Strengthened Concrete Beams, Author: Ahmed Mustafa, Location: Mills

abstract:
To delay the delamination of the externally bonded Fiber Reinforced Polymer (FRP)
laminate from the concrete surface and to ensure that after initial delamination the
FRP continue to carry some load, a new FRP mechanical anchor system was
developed and tested to delay complete delamination in RC beams externally
strengthened with FRP laminate. The anchor will be akin to a nail with a relatively
flat and wide head and a small diameter shank. It will be inserted into epoxy-filled
drilled holes in the concrete while its head will rest on the surface of the FRP
laminate and will be adhesively bonded to it. The advantage of this anchor is the
ease with which it can be used in different structural elements involving flexural
and/or shear strengthening with FRP laminates. The salient feature of the anchor is
its wide head to resist high interfacial shear stresses and its shanks that are inserted
inside the concrete to provide mechanical anchorage and to resist pullout.

A number of full scale RC beams, retrofitted with FRP sheets or laminates
will be tested to verify the validity of the concept and the effectiveness of the
proposed anchor in delaying/preventing delamination. Different oriented models
will be used to calculate the capacity of the tested beams. Finally, a modified model
to predict the interfacial shear and normal stresses with and without tension stiffness
is presented. The proposed anchor system can eliminate the delamination problem in
beams retrofitted for increased flexural strength. It could increase the delamination
load and allowed the FRP laminate to reach its full ultimate strength.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Jeremic, A.
Electrical and Computer Engineering

abstract: Title: Inverse Modeling of Diffusive Processes Using Instantaneous Measurements and Stochastic Differential Equations, Author: Ashraf Mohamed, Location: Mills

abstract:
Modeling the .dispersion of diffusive sources and signal processing algorithms for its prediction is an important issue in many applications such as cardiac activation, drug delivery,
and environmental monitoring. This work focuses on the development of computationally
efficient algorithms for modeling diffusion processes and estimation of their different
properties.

First, we implement the well known Fick's law of diffusion for localizing and estimating the properties of diffusive sources. Moreover, we propose a new model for the cardiac activation using inhomogeneous reaction-diffusion equations in the presence of diffusivity disorders. We also derive corresponding statistical signal processing algorithms for estimating (localizing) parameters describing these anomalies using ECG/MCG sensor arrays.

However, in some applications, such as drug delivery and capillary exchange process, where low-intensity diffusive sources are considered, random effects such as Brownian
motion should be accounted for. Hence, we propose a computationally efficient framework
for localizing low-intensity diffusive sources using stochastic differential equations. To
achieve computational efficiency, we model the dispersion using the Fokker-Planck equation
and derive corresponding inverse model and maximum likelihood estimator of source
intensity, location and release time. Also, we expand our stochastic model to account for
drift and propose an algorithm for the estimation of boundary properties.

Finally, we present a novel technique for modeling the exchange process and particle clearance in capillary networks using coupled stochastic- differential and Navier-Stokes equations. Numerical examples are used to demonstrate the applicability of our models.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Cross cultural validation of ND10-H and prevalence of neck pain in workers using computers in India.

title: CROSS CULTURAL TRANSLATION AND VALIDATION OF THE Neck Difficulty 10 (ND10) IN HINDI.

title: Prevalence of neck pain and related-disability in computer professionals in India

contributor:
MacDermid, Joy
Rehabilitation Science

subject: cross cultural translation

subject: hindi

subject: india

subject: computer workers

subject: prevalence

subject: neck pain

subject: neck difficulty 10

subject: outcome measure

subject: spiritual media publication organisation

subject: information technology

subject: neck disability

subject: DASH

subject: NDI

subject: SANE

subject: validation

subject: reliability

abstract:
Neck pain is the second most common musculoskeletal disorder after low back pain adding to the global burden of disease. A focus on evaluating outcomes for musculoskeletal conditions is imperative to evaluate the effect of interventions and to track the progression of disease. As evidence based practice and associated use of patient-based outcomes are taken up across different countries, it becomes imperative for cross-cultural translation studies. Given the uptake of technology in workplaces, it is also important to understand the prevalence of neck pain in this context. This thesis has focused on two objectives:
1.	Translating a newly developed patient-report outcome measure of neck-related disability and testing its psychometric properties.
2.	Estimating the prevalence of neck pain in computer-using workers.
	The first manuscript focusses on cross cultural translation and validation of ND10 (Neck difficulty10) that was designed to measure neck-related disability. A new English outcome measure for neck disability (ND10) was cross culturally translated and validated in computer users in India using forward and backward translation, and cognitive interviewing to determine a final version. The ND10-H demonstrated high reliability (ICC= 0.93) and convergent construct validity with the NDI and DASH (r= 0.78 and 0.86)
	The second manuscript reported the prevalence of neck pain in computer users in India. Sampling was performed in two different companies: A Spiritual Media Publication Organization (SMPO) and an Information Technology (IT) company. The companies were selected based on computer use and their willingness to participate. The survey was administered to all employees (n=150 & n=54) at these two companies.  The overall prevalence of neck pain was 64%. In the IT company, 78% of employees reported neck pain; and in the SMPO the prevalence was 40%. There were no significant differences in prevalence based on gender or age. All of the IT company computer users worked more than seven hours at their computers, while 38% of the SMPO workers did so. Chronic pain was present in 48%of the total sample.
	 The ND10-H can be used to assess neck-related disability in Hindi-speaking individuals. It should be accompanied by a valid pain measure when assessing patient outcomes. The prevalence of neck pain is high in computer-using workers in India.

abstract: Thesis

abstract: Master of Science Rehabilitation Science (MSc)


title: Stability and Well-posedness in Integrable Nonlinear Evolution Equations

contributor:
Pelinovsky, Dmitry
Mathematics and Statistics

subject:
integrable systems
partial differential equations
analysis

abstract: This dissertation is concerned with analysis of orbital stability of solitary waves and well-posedness of the Cauchy problem in the integrable evolution equations. The analysis is developed by using tools from integrable systems, such as higher-order conserved quantities, B\"{a}cklund transformation, and inverse scattering transform. The main results are obtained for the massive Thirring model, which is an integrable nonlinear Dirac equation, and for the derivative NLS equation. Both equations are related with the same Kaup-Newell spectral problem. Our studies rely on the spectral properties  of the Kaup-Newell spectral problem, which convey key information about solution behavior of the nonlinear evolution equations.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


contributor:
Valliant, John F.
Chemistry

abstract: Title: The Flourous Labelling Strategy: A New Paradigm in Preparing Radiolabelled Compounds in High Effective Specific Activity, Author: Amanda C. Donovan, Location: Mills

abstract:
A new radiolabelling strategy suitable for preparing radioiodinated
compounds in high effective specific activity was developed. The core method
employs fluorous chemistry in such a manner that unlabelled precursors can be
separated from labelled compounds without the use of HPLC purification. The
fluorous labelling strategy involved tin-aryl groups in which the substituents off
the metal were fluorine rich. Upon reaction with radioiodide and an oxidant, the
tin-aryl bond is cleaved. The non-fluorous product could then be separated from
the fluorous starting material by fluorous solid-phase extraction (F-SPE).

The initial goal of this thesis was to first establish the viability of the
fluorous labelling strategy (FLS). To this end, fluorous benzoic acids, 3- and 4-
(tris[2-perfluorohexylethyl]stannyl) benzoic acid (m- and p-2.1) were prepared via
organozinc derivatives and subsequent hydrolysis. Following direct iodinolysis of
m-2.1 using a sub-stoichiometric amount of iodine, the fluorous benzoic acids
were treated with Na[1251]1. After purification via fluorous solid-phase extraction,
the resulting iodinated benzoic acids (m- and p-2.5) were prepared in 92 and 93
%yield and excellent purity (>98% by HPLC).

Next, to demonstrate that the FLS could be used to create libraries of both
precursors and labelled compounds, a small collection of benzamides were
prepared from fluorous tetrafluorophenyl active esters (m- and p-2.9). An excess
of a series of simple amines were added to reaction wells containing one of the
two fluorous active esters and the products purified by taking advantage of the non-fluorous nature of the reagents and reaction byproducts. All products, which
were fully characterized and their purities verified by HPLC, were subsequently
labeled with 1251 in high radiochemical yield (> 85 %), and the products were
obtained in greater than 98% radiochemical purity.

To demonstrate the applicability of this method clinically relevant
radiopharmaceuticals, a fluorous precursor of the radiopharmaceutical metaiodobenzylguanidine
(MIBG) was prepared via the fluorous benzylamine, 3-tris[2-
perfluorohexylethyl]stannyl) benzylamine (3.3) upon reacting with 1H-pyrazole
carboxamidine. Following radioiodination, high purity C251]- and [1231]MIBG were
produced in 81±3% and 80% radiochemical yield respectively in less than 20 min
without high-performance liquid chromatography (HPLC) purification. The purified
product contained less than 1 ppm tin as determined by inductively coupled
plasma-mass spectrometry (ICP-MS).

Next, the FLS was expanded to include fluorous precursors suitable for
reacting with groups common in peptides and proteins for use in bioconjugation
reactions. Among these were a fluorous isocyanate (4.1) which was shown to be
stable in fluorous solvents for up to 3 weeks, fluorous benzaldehydes (m- and p-
5.1) and a fluorous iodoacetamide (5.3). Following their purification and
characterization, these compounds were each reacted with model systems (e.g.
amines, amino acids) and were subsequently radioiodinated using Na[1251]1 in
good yields ( > 80 %) and in very high purity(> 98 %) as determined by HPLC.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


contributor:
Wilkinson, D. S.
Materials Science and Engineering

abstract: Title: Void Growth and Coalescence Studied by X-Ray Computed Tomography, Author: Akihide Hosokawa, Location: Mills

abstract:
Void growth and coalescence were investigated by means of in situ X-ray
computed tomography coupled with tensile deformation. A variety of model
materials were fabricated whereby artificial three dimensional void arrays were
embedded in metal matrices. An ultra short-pulsed laser machining system
and diffusion bonding technique were used to produce those model materials.
Model materials containing a pair of round notches were also produced to investigate
the effect of stress triaxiality. In situ X-ray tomography experiments
successfully visualized the void growth and coalescence events in the model
materials produced. The void growth behavior was quantitatively analyzed by
measuring the principal diameters of the internal voids.

For several model materials, a new technique called continuous tomography was applied. The experiments were performed at the beamline ID15 of the European Synchrotron Radiation Facility (ESRF), France. This technique allows us to keep taking a series of tomographic scans during non-stop tensile
deformation. This new technique enabled us to experimentally capture the plastic strains at the onset of void coalescence for the model materials. The onset of void coalescence here was defined as the point at which the lateral shrinkage of voids terminates. The captured plastic strains at the onset of void coalescence were compared for the first time ever with the existing void coalescence models which are essentially designed to predict the onset of coalescence
instead of the simple linkage of voids.

Similar experiments were also conducted using a set of notched model materials at the same beamline ID15. A significant influence by the higher stress triaxiality and the strain concentration induced by the notches on the
void growth in these model materials was observed. This aspect was confirmed
by the FE simulation performed. The captured linkage strains were used to
assess the validity of the void coalescence models at a higher stress triviality.

Model materials made of Glidcop and brass were also tested using the
same methodology. This set of experiments were performed at the beamline
BL20XU of SPring-8, Japan. The results obtained from these samples suggested
that the higher work hardening exponent in brass stabilized the plastic
flow of the ligament while the lower work hardening exponent in the Glidcop
materials significantly accelerated the linkage events. Nevertheless, the critical
values of work hardening rate normalized by the current flow stresses were
quite similar (lower than the critical value of localized necking) in individual
materials (copper, Glidcop, brass) even if the plastic strains at linkage and
coalescence events of the materials are different.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Effects of Siltation on Corals of the Great Barrier Reef Near the Daintree River, North-Eastern Queensland, Australia

contributor:
Risk, Michael J.
Geology

subject: siltation, corals, great barrier, reef, daintree river, clastics, sediments, decalcification, algal banding

abstract:
 Effects of siltation were measured by determination of growth rates through x-radiography and trapped clastics sediments through coral sample decalcification. Results show an increase in growth rate with an increase in suspended particulate matter. This is attributed to an increase in nutrient levels with increased SPM values.

 Support of algal banding being an annual indicator was given by comparison of x-radiographs to actual coral slabs.

 Observation of radiographs reveal an offshore trend in regard to the distinctiveness of annual banding, with the bands being less obvious on outer shelf corals.

 Large variations in growth rates found within the sample population as a whole, as well as intra-reef samples reveal the limited applications to which these determinations can be used.

abstract: Thesis

abstract: Bachelor of Science (BSc)


title: Spaced Cleavage Development in the Metagreywackes of the Goldenville Formation, Meguma Group, Nova Scotia

contributor:
Clifford, P. M.
Crocket, J. H.
Geology

subject: spaced, cleavage, development, Metagreywackes, Goldenville Formation, Meguma Group, quartz, grain, rhombs

abstract:
 The greywackes of the Goldenville Formation, Meguma Group, Nova Scotia display a well developed spaced cleavage. The cleavage is characterized by zones of mica enrichment and associated quartz depletion and forms a network of anastomosing cleavage rhombs. Parallelism between cleavage and water escape structures suggests that the cleavage was emplaced perpendicular to bedding early in the deformational history of the rocks. Subsequent passive rotation of cleavage and water escape structures reduced the bedding-cleavage angle to its present values.

 XRF whole rock analyses of cleavage planes and lithons from two different sample locations show that the cleavage is depleted in SiO2, CaO, Na2O and enriched in Al2O3, Fe2O3, MgO, K2O, TiO2, MnO and P2O5 relative to lithons. Mass balance calculations based on the Gresens (1967) approach indicate that the cleavage with respect to the lithon represents a 40%-60% volume loss. Using the volume loss it can be shown that the cleavage lost SiO2, Na2O, CaO, MnO, P2O5, Pb, Sr, Nb, and Y and gained MgO, K2O, Ba, Rb, and W during its formation. TiO2, Al2O3, Fe2O3 and Zr remain relatively immobile during the cleavage forming processes. The behavior of Au, Sb, As, Ce, Nd, and La can not be discerned.

 The cleavage was initiated by pressure solution at grain contacts. However, several of the above mentioned chemical migrations increased the solubility of quartz and therefore greatly enhanced the development of the cleavage.

abstract: Thesis

abstract: Master of Science (MSc)