title: Charity and Social Reform: Civic Virtue, Spiritual Orthodoxy, and Local Identity in Seventeenth-Century Marseilles

contributor:
Armstrong, Megan
Kaczynski, Bernice
Aksan, Virginia
History

subject:
Marseilles
Early Modern Period
Charity
Enfermement
Poverty
Catholic Reformation
European History
European History

abstract: This work is a local study of charity in seventeenth-century Marseilles. Civic councillors, inspired by the dévot movement, were the chief agents of charitable poor relief. Responding to external political pressures from the Bourbon monarchy and religious inspiration from within the community, charity became a facet of local political authority and a vehicle of social moral reform. The collective purpose of the newly emerging specialized asylums was to mould orderly and spiritually orthodox members of society. In light of the city’s ongoing hopes for civic autonomy and its unwavering commitment to Catholicism, the desire for citizen-virtue crystallizes as a struggle for distinctly Marseillais identity. My study emphasizes not the ‘enfermement’ but the concept of ‘charity’ as the central concept in treatment of the poor. The asylums were ‘rehabilitative’ rather than purely punitive. In showing charity as a mechanism of social reform – tailored to each group’s material, moral and spiritual lowliness and to the threat they allegedly posed – the study implicitly unveils the exclusionary aspects of the social mosaic.

abstract: Doctor of Philosophy (PhD)


title: THE ROLE OF SREBP-1 IN MEDIATING ANGIOTENSIN II- INDUCED KIDNEY FIBROSIS

contributor:
Krepinsky, Joan
Austin, Richard
Medical Sciences

subject: renal firbosis SREBP angiotensin

subject: Biochemical Phenomena, Metabolism, and Nutrition

abstract: End stage renal disease (ESRD) has been a world-wide cause of renal disease-related fatality. Most patients with ESRD progress through chronic kidney disease (CKD). There are various causes of CKD including mechanical stress, infections, high blood pressure or immune conditions. Renal fibrosis is known to play an important pathogenic role in CKD and ESRD. Transforming growth factor-beta (TGF-ß) is one of the major mediators of fibrosis, and inhibition of TGF-ß could reduce renal fibrosis in in vitro models. One of the well - known inducers of TGF-ß transcr iption is Angiotensin II (ANGII). 1 This is a major contributor to the matrix accumulation and glomerular fibrosis leading to a decline in kidney function and kidney failure in patients with chronic kidney disease (CKD). 2 A recent study demonstrated that TGF -ß could be increased by SREBP -1c overexpression. 3 My laboratory’ s data showed that ANGII could induce TGF-ß on a transcriptional level, and this induction could be block ed by Fatostatin, an SREBP/SCAP inhibitor. My data showed that ANGII could induce SREBP-1 in a time and dose dependent manner. Therefore my study focused on understanding the role of SREBP-1 in ANGII-induced TGF-ß upregulation in primary mesangial cells (MCs). We found that ANGII- induced TGF-ß promoter activity requires Angiotensin type 1 receptor (AT1R) and SREBP-1 activation as well as ER stress. Interestingly , the activation of SREBP-1 by ANGII stimulation relies on ER stress and PI3K/AKT signaling. Both ANGII and ER stress inducer s could induce AKT phosphorylation, indicat ing that ER stress is an upstream mediator in th is signaling pathway. We also found that ER stress inhibit ion could block SREBP-1 activation by ANGII stimulation and, more importantly , could also block ANGII- induced TGF-ß promoter activity. In C57BL/6 mice infused with ANGII for one week, we found that both SREBP-1 and GRP78 were significantly upregulated in glomeruli in the ANGII infusion group compared with the control group. Taken together , this data indicates that ER stress is required for SREBP-1 activation, both of which are mediators of kidney fibrosis.

abstract: Master of Science (MSc)


title: The Philippeion at Olympia: The True Image of Philip?

contributor:
Corner, Sean
Pope, Spencer
Haley, Evan
Classics

subject:
Philip II of Macedonia
Philippeion
Philippeum
Olympia
Chaeronea
Macedonian kingship
Classical Archaeology and Art History
Other Classics
Classical Archaeology and Art History

abstract:
The aim of this thesis has been to consider how Philip II of Macedonia presented himself to the Greek peoples after the Battle of Chaeronea in 336 BC. It examines the context and program of the Philippeion at Olympia in order to determine how Philip II negotiated his royal status in response to Greek opinion. This study takes into account the traditional role of the Macedonian kings, how they typically portrayed themselves, and to what purpose. It also explores Philip's propaganda specifically and the differing responses of various Greek peoples.
Although Philip's role as Hegemon of the League of Corinth seems to be at odds with the Philippeion's classification as a victory monument and a display of the king's authority, further examination reveals that the Philippeion conforms with Philip's program of propaganda. It's message is also adaptable to the various perceptions of the Greek peoples as well as any Macedonian viewers.

abstract: Master of Arts (MA)


title: Neutron Scattering Studies of the Quantum Spin Ice Material Yb2Ti2O7

contributor:
Gaulin, Bruce D.
Physics and Astronomy

subject:
geometric frustration
neutron scattering
crystal growth
magnetism
quantum disorder
Condensed Matter Physics
Condensed Matter Physics

abstract:
Yb2Ti2O7 is one member of a series of magnetic compounds with the pyrochlore lattice structure. For specific types of single-ion anisotropy and exchange interactions, the geometry of the pyrochlore lattice frustrates near-neighbor interactions and coaxes a wide variety of unusual magnetic ground states from such compounds. Yb2Ti2O7 is unique among these compounds in that the source of the frustration is not immediately obvious when one considers the combination of single-ion anisotropy (XY-like) and the nature of the exchange interactions (ferromagnetic) present therein. A conventional magnetic transition was indeed initially expected based on the observation of specific heat anomaly near 200mK. However, many studies produced no signs of long-range magnetic order below this temperature. Intriguingly, above the transition, evidence for unusual two-dimensional correlations came in the form of rods of magnetic diffuse neutron scattering. This thesis contains four articles that detail the results of several neutron scattering studies on Yb2Ti2O7. The goal of these studies was to determine the nature of the static and dynamic spin correlations throughout the magnetic field vs. temperature phase diagram of Yb2Ti2O7.

We first performed a time-of-flight neutron scattering experiment on a single crystal of Yb2Ti2O7, which we prepared using the optical floating zone method. This initial study provided a comprehensive survey of the phase diagram, including the previously unexplored response to a magnetic field. We found that the rods of diffuse scattering change qualitatively upon cooling below the temperature of the reported specific heat anomaly, showing signs for the development of short-range three-dimensional correlations. Additionally, we discovered that a relatively small magnetic field applied along the [110] direction could remove the diffuse scattering entirely, and produce sharp spin wave excitations in the inelastic channel, indicating long range spin correlations.

We further quantified the temperature dependence of the diffuse scattering in zero-field using a triple-axis neutron spectrometer. The crossover from two-dimensional correlations to short-range three-dimensional correlations was found to begin at 400mK and reach completion near the temperature of the specific heat anomaly, ∼200mK. Our measurements of the low temperature specific heat of several single crystal samples, as well as a powder sample, revealed that significant sample-dependence of the magnetic properties exists. The single crystal samples were shown to have broader features in the specific heat at relatively low temperatures compared to the powder samples, pointing to some amount of structural disorder in the single crystals.

To understand the nature of the structural defects in the single crystals, we compared the structure of a crushed single crystal of Yb2Ti2O7 to that of a powder sample using neutron powder diffraction. The major conclusion of that work was that the single crystal is non-stoichiometric, containing 2.3% excess ytterbium on the (non-magnetic) titanium sublattice. The introduction of additional magnetic moments into the system is expected to be the cause of the sample-dependence of the specific heat anomaly.

Finally, we fit the spin wave dispersions in the field-polarized state, as measured by time-of-flight inelastic neutron scattering, to an effective spin-1/2 anisotropic exchange Hamiltonian. The microscopic parameters extracted from these fits place Yb2Ti2O7 close to exotic Quantum Spin Liquid phases predicted for the anisotropic spin-1/2 pryochlore model. The exchange parameters also reveal that the source of the frustration in Yb2Ti2O7 comes from the “quantum spin ice” nature of its exchange interactions.

abstract: Doctor of Philosophy (PhD)


title: Investigation into the Unique Roles of MMP-2 and MMP-9 in TGFβ-Induced Epithelial-Mesenchymal Transition in Lens Epithelial Cells

contributor:
West-Mays, Judith
Medical Sciences

subject:
EMT
cataract
lens
MMP
TGFβ
Medical Cell Biology
Medical Cell Biology

abstract:
Epithelial-mesenchymal transition (EMT) is a pathological process leading to the formation of anterior subcapsular cataract (ASC). Mediated by transforming growth factor beta (TGFβ), EMT involves the transformation of the monolayer of lens epithelial cells (LECs) into spindle-shaped myofibroblasts, which manifest as plaques directly beneath the lens capsule. TGFβ-induced EMT leading to ASC has been associated with the upregulation of two specific matrix metalloproteinases (MMPs), MMP-2 and MMP-9. Having identified MMP-2 and MMP-9 as participants in the formation of cataracts, the specific roles of either of these MMPs have yet to be determined.

The current study utilized MMP-2 and -9 knockout (KO) mice to determine their unique roles in TGFβ-induced EMT. First, adenoviral injection of active TGFβ1 into the anterior chamber of MMP-2 KO mice led to the formation of distinct αSMA-positive anterior subcapsular plaques, in contrast to treated MMP-9 KO eyes, which were resistant. Additionally, an ex vivo mouse LEC explant system was established in these KO lines. In the isolated lens epithelial explants, TGFβ triggered a transformation of LECs from a tightly packed cuboidal monolayer to an elongated mesenchymal phenotype. This process involved a disruption in epithelial cell contacts indicated by a loss of E-cadherin, and an acquisition of myofibroblast marker, αSMA. In the absence of MMP-2, TGFβ was still able to induce EMT with E-cadherin loss and concurrent αSMA expression. In contrast, LEC explants from MMP-9 KO mice treated with TGFβ did not acquire a characteristic spindle-like phenotype and showed substantially less αSMA expression. Results from both of these approaches were consistent; MMP-2, but not MMP-9, KO mice stimulated with TGFβ exhibited phenotypic changes typical of those described in ASC formation, namely a loss in cell attachments, multilayering of previously epithelial-like cells, and αSMA reactivity. Therefore, while MMP-2 is not necessary, MMP-9 is critical to TGFβ-induced EMT in LECs.

abstract: Master of Science (MSc)


title: ANALYSIS OF LIQUID POOLING DURING LATE-STAGE SOLIDIFICATION

contributor:
PROVATAS, NIKOLAS
Materials Science and Engineering

subject:
Late-stage
Solidification
Coalescence
Spectral Analysis
Clustering Analysis
Hoshen-Kopleman
Length-scale selection
Metallurgy
Metallurgy

abstract: Grain structure and secondary phases play a critical role in determining the mechanical properties of industrial alloys. The spatial variation of such phases is very closely correlated to the liquid pooling established during late stage solidification and grain boundary coalescence. Obtaining a theory that correlates the evolution of length scales during grain boundary coalescence is a critical step toward the optimization of commercial alloys. This thesis highlights various phenomena that enter such a theory. They include coarsening and coalescence of dendrites, nucleation mechanisms and changes in composition of inter-dendritic liquid where second phases tend to initially form. Quantitative phase field models of solidification to simulate casting conditions and microstructure evolution are used in combination with characterization techniques to illustrate the connection between number, size, and distribution of liquid pools. Characterization techniques include spectral analysis, and clustering analysis by way of the Hoshen-Kopleman algorithm. By characterizing late-stage liquid pools, this thesis aims to be a first step towards developing a statistical scaling theory of length scale of liquid pooling.

abstract: Master of Applied Science (MASc)


title: Investigating The Effects of Tenure Mix In Toronto's Regent Park Community

contributor:
Dunn, James R.
Gillett, James
Wilton, Robert
Health and Aging

subject:
Social Mix
Tenure Mix
Public Housing
Urban Poverty
Policy Design, Analysis, and Evaluation
Social Policy
Urban Studies
Policy Design, Analysis, and Evaluation

abstract: Policies of tenure mix have been widely adopted in many industrialized nations and are often justified as a means of attenuating the detrimental effects of concentrated urban poverty. In this thesis, the case of Toronto’s Regent Park community is examined. It is the first large-scale mixed tenure redevelopment of a publicly subsidized housing community in Canada. Using a series of 24 semi-structured qualitative interviews with residents from both tenures, I examine their experience of living in a mixed tenure community and gauge their support for policies of tenure mix more generally. Broader determinants of residential satisfaction in the neighbourhood are also examined. The redeveloped Regent Park is considered to be a relatively safe, convivial, well-serviced, well-situated, and aesthetically pleasing neighbourhood by individuals from both tenures. Further, participants from both tenures expressed support for the ostensible goals of the redevelopment. Resident experiences diverge significantly by tenure with regard to their satisfaction with the management and maintenance of their buildings. Particularly, individuals in the public buildings expressed considerable displeasure with how their buildings were managed and experienced serious physical difficulties that, in some cases, had adverse effects on their health and wellbeing. I find that tenure mix enjoys considerable support from residents of both tenures, with especially strong support evinced by a subset of condominium residents. To assess the efficacy of tenure mix, I employ a conceptual framework provided by Joseph (2006) and find some evidence that the redevelopment has strengthened the social capital of publicly-subsidized tenants. For most residents, more proximal concerns take precedence over the mixed nature of the community.

abstract: Master of Arts (MA)


title: Razian Authority and Law

contributor:
Waluchow, Wilfird
Sciaraffa, Stefan
Doubleday, Nancy
Philosophy

subject:
Raz
legal philosophy
service conception
Other Philosophy
Other Philosophy

abstract: In this thesis, I will examine the consequences of applying the legal philosophy of Joseph Raz in real world situations. I will argue that if most legal systems actually attempted to adhere to, and accept his theory in all its parts, the legal systems in question would have serious problems. In particular, the legal authorities and officials which represent the legal systems in question would be confused about the extent of their authority. After I prove my claim, I will offer a solution to the problem.

abstract: Master of Arts (MA)


title: POSTURAL AND MUSCULAR ADAPTATIONS TO REPETITIVE SIMULATED ASSEMBLY LINE WORK

contributor:
Keir, Peter
Dr. Jim Potvin, Dr. Jim Lyons
Kinesiology

subject: repetitive movement; posture; upper extremity; surface EMG;

subject: Biomechanics

subject: Motor Control

subject: Biomechanics

abstract: Few studies have shown the process of adaptation in muscle activity and joint angle during prolonged repetitive work. Fifteen healthy men performed 1 minute cycles of automotive-related tasks, which included a finger pull, knob turn, drill press and hose connector push. The experiment occurred on two days, separated by 24 hours. Day 1 required 61 cycles, with 5 cycles on day 2. Electromyography and kinematics of the upper extremity were analyzed at 12-minute intervals. Time to complete work cycle decreased by 6.3 s at the end of day 1 and 5.3 s on day 2. Peak EMG decreased for triceps brachii (TB), anterior deltoid (AD) and infraspinatus (IN) during work cycle, TB (finger pull), biceps brachii (BB), TB, AD, middle deltoid (MD) and IN during the hose insertion task. Peak EMG increased for MD and IN during the drill task. Mean EMG decreased for MD (work cycle), BB (hose insertion) and AD (finger pull), while MD and IN increased (drill task) and upper trapezius increased during the work cycle. EMG COV decreased for TB, AD, posterior deltoid and IN during the work cycle, TB during the finger pull task and AD during the hose insertion task. COV increased for BB during the work cycle, AD during the finger pull and for BB and lower trapezius during the drill press. Peak shoulder flexion decreased by 7.0° during the work cycle. Perceived discomfort increased by 1.2 units. This thesis found adaptations to highly repetitive but light work in only one hour, some of these changes persisted through the next day suggesting an adaptive process. This thesis is one of the first to examine adaptations to a highly repetitive simulated assembly work and has provided new insights into the evaluation of repetitive jobs as a whole and as isolated subtasks.

abstract: Master of Science in Kinesiology


title: Survey of Acute Rehabilitation in Canadian Intensive Care Units

contributor: Gordon Guyatt, Karen Choong, Margaret Herridge

contributor: Clinical Epidemiology/Clinical Epidemiology & Biostatistics

subject:
early mobilization
acute rehabilitation
intensive care
Other Medical Specialties
Other Medical Specialties

abstract:
Background & Rationale: Early mobilization (EM) can minimize intensive care unit aquired weakness (ICUAW) among survivors of critical illness. Clinician awareness of ICUAW, perceived barriers to EM, and acute rehabilitation in Canadian ICUs have not been well described.

Objective: To assess (1) awareness of ICUAW and EM, (2) perceived institutional, clinician, patient level barriers to EM, (3) stated practice of acute rehabilitation in Canadian ICUs.

Design: A cross-sectional, self administered postal survey

Setting: Academic Intensive Care Units (ICUs) in Canada

Subjects: 134 physiotherapists and 302 critical care physicians

Interventions & Measurements: Item generation followed a review of relevant literature and discussion with 26 content experts. We reduced the survey to 10 domains and 29 specific questions. The survey intrument was piloted and evaluated for clinical sensibility and intra-rater reliability. Up to 3 surveys were mailed to potential respondents. Descriptive statistics were reported as proportions, means (+/- SD) or mode, as appropriate. We used the chi-squared test to compare proportions and multi-variate logisitc regressions to test for association between independent and dependent variables.

Main Results: The survey instrument had excellent clinical sensibility and good intra-rater reliability (Cohen’s kappa > 0.4). The overall response rate was 71.3% (311/436) including 87.3% (117/134) of physiotherapists and 64.2% (194/302) of physicians. The incidence of ICUAW in the general medical-surgical population was under-recognized by 68.8% of clinicians and 59.8% of clinicians stated they were either insufficiently trained or informed to mobilize mechanically ventilated patients. Excessive sedation and medical instability were perceived as the most important patient barriers. Limited staffing, safety concerns (by nurses) and delayed clinician recognition to initiate EM were key provider barriers to EM. Important institutional barriers to EM included insufficient guidelines and equipment. Only 19.9% of clinicians stated that patients with suspected ICUAW were referred to an out-patient clinic after ICU discharge for long term rehabilitation.

Conclusions: Over 60% of respondents to this national survey underestimated the incidence of ICUAW and do not feel adequately trained to mobilize mechanically ventilated patients. Multiple patient, provider and institutional barriers may also contribute. Clinical leaders and administrators should consider these modifiable factors when designing EM programs in the ICU.

abstract: Master of Science (MSc)


title: Electrical Transport Properties of Metal-Insulator-Semiconductor (MIS) and Semiconductor-Insulator-Semiconductor (SIS) Structures

contributor:
Shewchun, J.
Physics

subject: Physics Physics

abstract:
The major purpose of the work presented in this thesis has been to consider some important electrical transport properties of Metal-Insulator-Semiconductor (MIS or MOS) and Semiconductor-Insulator-Semiconductor (SIS) diodes.

In particular the d.c. tunnel current-voltage characteristics of the MIS diode are studied and shown to divided naturally into two categories corresponding to the state of equilibrium of the semiconductor of a diode. In "equilibrium" diodes the carrier distributions in the semi-conductor are effectively maintained in thermal equilibrium despite the presence of d.c. current flow. I-V characteristics of a range of this type of diode are presented and analyzed. Tunnel induced non-equilibrium conditions in the semiconductor are also investigated and shown to have visible effects on the I-V characteristics of the MIS tunnel diode. These effects are seen to be functions of oxide thickness, minority carrier supply rate and doping density.

The tunnel currents of both "equilibrium" and "non-equilibrium" diodes are analyzed by comparison with a comprehensive finite temperature tunnel theory. Employment of numerical techniques permits the inclusion in these calculations of the effects of a two band model of the insulator, image force potentials in the barrier and space charge tunneling.

A practical application of the properties of the "non-equilibrium" diode in the form of a new type of active device, the Surface Oxide Transistor (SOT), is demonstrated. The characteristics of such structures are investigated and models of their operation proposed.

The final work presented in this thesis deals with a new type of barrier dominated semiconductor structure, the SIS diode. The capacitance-voltage (C-V) and conductance-voltage (G-V) characteristics of thick oxide diodes of this type are presented and compared with theory. A wide range of interesting characteristics are observed. The d.c. current-voltage behaviour of the SIS tunnel diode, while not studied experimentally, is compared qualitatively with that of the MIS tunnel diode.

abstract: Doctor of Philosophy (PhD)


title: An Efficient Approach For Dynamic Stability Analysis of Power Systems - Including Load Effects

contributor:
Alden, R.T.H.
Electrical Engineering

subject:
Electrical and Electronics
Electrical and Electronics

abstract:
This thesis describes an efficient approach for modeling and analysing small signal (dynamic) stability of balanced interconnected power systems. Systems are modeled into the state-space form where a partitioning technique is used to systematically reduce system equations into that form. Consequently, eigenvalue and eigenvalue sensitivity methods are used for dynamic stability prediction.

The formulation technique allows the inclusion of nonlinear and dynamic load representation and network and shaft dynamics in addition to detailed generator, turbine-governor and excitation system simulations currently being used by industry. The partitioning approach eliminates the need for storing large blocks of null elements. It also preserves the identity of various sub-systems. Consequently, this approach is particularly economical in studies involving system modification updating.

An algorithm is developed to calculate eigenvalue second-order sensitivities with respect to system control and design parameters. The sensitivities are obtained in terms of the eigenvalues and eigenvectors of the base case coefficient matrix. It is shown that the inclusion of the second-order terms in an overall sensitivity package does not add any computational complexity.

Eigenvalue first and second-order sensitivities are combined with an inverse iteration technique in an efficient algorithm for tracking possible movement of any sensitive subset of system eigenvalues due to parameter changes. The method is applicable in situations where a relatively small number of eigenvalues are critical in describing system dynamic stability. The efficiency of this algorithm over the repeated eigenvalue method is demonstrated.

These concepts and techniques are applied to a number of practical problems currently receiving attention in the power industry. In particular situations involving insufficient damping torque due to interaction between turbine-generator and network dynamics, turbine-generator and stabilization control, and the effect of static excitation and induction motor loads are analysed.

The interactions between system composite loads and excitation-stabilization control loops are examined on a reasonably general basis. It is shown that load characteristics have a considerable effect on system stability. It is also shown that there are specific situations where the choice of the load model can make a difference in stability prediction. In particular, at light generation levels the use of a power system stabilizer with a constant power local load leads to a prediction of instability while stability is predicted for a constant impedance load model.

abstract: Doctor of Philosophy (PhD)


title: MOLECULAR DYNAMICS SIMULATION STUDY OF SOLID-LIQUID INTERFACE PROPERTIES OF HCP MAGNESIUM

contributor:
Hoyt, Jeffrey J.
Materials Science and Engineering

subject:
MD simulations
solid-liquid interface
interfacial free energy
interfacial structure
HCP Magnesium
Materials Science and Engineering
Materials Science and Engineering

abstract:
The structural and thermodynamic properties of a crystal-melt interface in

elemental magnesium have been investigated using molecular dynamics (MD)

simulations with an embedded atom method description of the interatomic potential.

Three low index interfacial orientations, (0001), (1101) and (1120), have been studied.

From fine-grained atomic density profiles, the structural interfacial widths show obvious anisotropy and the variation of interatomic planar spacing as a function of distance through the crystal-melt boundary is established. Mainly from the coarse-grained density profiles, the effective 10-90 width of the interface region, defined as the intrinsic width, in each orientation has been determined. In addition, the interfacial stresses are obtained from an integration of the interfacial stress profiles and the results show significant anisotropy, which is possibly related to the anisotropy of occupation fraction profiles. Finally, from a determination of the excess energy and interfacial stress of the solid-liquid interface and from previous published results for the interfacial free energy at the melting point, the Gibbs-Cahn integration is employed to derive an estimation of the temperature dependence of the interfacial free energy at non-equilibrium temperatures. All of the crystal-melt interfacial properties for magnesium are compared with simulation data from other elemental metals and alloys, as well as from other model systems such as Lennard- Jones and hard spheres.

abstract: Master of Applied Science (MASc)


title: Person Centred Palliative Care: A First Nations Perspective

contributor:
Brazil, Kevin
MacMillan, Harriet
Lohfeld, Lynne
Health Research Methodology

subject:
Aboriginal
First Nations
Palliative Care
End-of-Life
Health Policy
Other Medicine and Health Sciences
Health Policy

abstract:
Introduction: Palliative care in Canada is an under-funded service for all Canadians, but for Aboriginal people in Canada, the level of access to such care is significantly lower. This study examined the system of palliative care delivery at Six Nations of the Grand River. The overall aim of the project was to identify ways on how the system of care could be improved.

Methods: A qualitative case study approach was used. Interviews were held with Elders and family caregivers to identify the priorities in care delivery from their perspective. Focus groups were held with representatives from palliative care service provider agencies in an effort to identify the strengths and challenges within the system and to determine how palliative care services provided to the members of Six Nations could be improved.

Findings: Themes identified in the interviews included: personable, caring care; culturally-competent care; open two-way communication; support for family caregivers; palliative home care should be available; meeting comfort needs of the person; and the need for a hospice in the community. The main theme identified in the focus groups with care providers included: relationship/rapport issues between provider organizations; within-program strengths and challenges; cultural considerations in care; and broader system factors that influence care.

Discussion: Relationship/rapport issues were identified as a challenge, and it appeared that the focus groups provided an opportunity for communication between the organizations to improve. Identification of within-program challenges – and ways to address these challenges - may provide opportunities for each organization to improve how palliative care services are delivered at Six Nations. Identification of broader system factors that influence care may also benefit patients in need of palliative care.

abstract: Master of Science (MSc)


title: Possible Intrinsic adjuvanticity of the Amb a 1 (Ambrosia artemisiifolia :Ragweed) allergen

contributor:
Larché, Mark
Biochemistry

subject:
Allergy
Ragweed
Immunology
LPS
Immune System Diseases
Molecular Biology
Immune System Diseases

abstract: Amb a 1 is the major allergen found in ragweed. Our observations have suggested that Amb a 1 may bind lipopolysaccharide (LPS), which would likely contribute to the allergenicity of Amb a 1. In order to assess whether Amb a 1 can bind LPS, peptide sequences from Amb a 1 were assayed for their ability to bind to LPS using an ELISA based LPS binding assay. A 15 amino acid sequence in the β- chain of Amb a 1 demonstrated affinity for biotin labeled E. coli LPS. The sequence also bound to P. aeruginosa LPS, which is structurally disparate in the lipid A region, indicating that the sequence has flexibility in recognizing different lipid A moieties, or that the binding site may not include the lipid A portion of the LPS molecule. An IL-10 ELISA was also used to determine whether the LPS bound to the peptides induced an immunological response in leukocytes. Peptides containing the LPS-binding sequence were able to bind to LPS and induce IL-10 production, suggesting the interaction between Amb a 1 and LPS may have immunological consequences. We have identified a sequence within the major ragweed allergen Amb a 1 that has the potential to bind to LPS. This indicates that the allergen may provide its own adjuvant when encountered by the immune system, leading to an enhanced immunological response to an otherwise innocuous environmental protein.

abstract: Master of Science (MSc)


title: The Dynamic Role of Subphonemic Cues in Speech Perception: Investigating Coarticulatory Processing Across Sound Classes

contributor:
Yoon, Tae-Jin
Connolly, John
Moro, Anna
Cognitive Science of Language

subject:
Spoken Word Recognition
Event-Related Potentials (ERP)
Subphonemic Coarticulation
Cognition and Perception
Linguistics
Phonetics and Phonology
Psycholinguistics and Neurolinguistics
Cognition and Perception

abstract: Neural responses to anticipatory coarticulatory cues were investigated across systematically varying phonological conditions. Congruent or incongruent subphonemic information was placed between an initial consonant and a vowel in a consonant-vowel- consonant (CVC) spoken word (Archibald & Joanisse, 2011). Due to physical and temporal differences across sound classes, the objective was to investigate whether coarticulatory information would be processed differently across controlled manipulations of onset (fricative vs. stop) and vowel type (height vs. backness). Event- related potentials (ERPs) were recorded during a printed-word/spoken-word matching paradigm, in which participants indicated whether a visual prime stimulus and a spoken word matched/mismatched. The “Phonological Mapping Negativity” (PMN) component provides strong evidence that the use of coarticulatory information in speech recognition varies in strength and timing as a function of onset type (fricative vs. stop) and vowel height (high vs. low). Coarticulatory cues were more readily perceived in spoken word beginning with fricatives than with stops. Similarly, subphonemic variations were more easily detected in low vowels than in high vowels. Observed perceptual and temporal differences are interpreted to reflect variations in subphonemic and phonological processing.

abstract: Master of Science (MSc)


title: Investigating Diet and Regional Origins in the Smith's Knoll Skeletal Sample, Stoney Creek, Using Stable Isotopes

contributor:
Prowse, Tracy
Brickley, Megan
Schwarcz, Henry
Anthropology

subject:
War of 1812
Battle of Stoney Creek
Stable Isotopes
Diet
Regional Origins
Long-Term Residency
Archaeological Anthropology
Biogeochemistry
Biological and Physical Anthropology
Military History
United States History
Archaeological Anthropology

abstract: This thesis uses stable isotopic analysis to identify diet, geographic origins and long-term residency in a sub-sample of the Smith’s Knoll skeletal collection, soldiers who died during the June 6th 1813 Battle of Stoney Creek. The major objectives of this study have been to differentiate between two major modes of dietary consumption, one wheat-based, the other maize-based, in an attempt to decipher British colonial from American soldiers. These objectives were paired with stable oxygen and strontium isotopes, two isotopic elements presently used to identify migration and regional origins. Oxygen isotopic results from teeth suggest that, as children, 5 individuals may have originated in North America. Nine individuals have isotopic signatures indicative of both a North American or United Kingdom origins. The isotopic composition from bone collagen and phosphate suggest similar geographic origins, with diets composed of both wheat- and maize-based foods. Bone phosphate values indicate that 2 individuals possibly resided in North America. The remaining 20 individuals have bone values indicative of long-term residency in both geographic regions with a significant amount of dietary mixing. These results suggest that other military participants, soldiers from the King’s 8th Regiment and Canadian militiamen, may also be represented in this study. Prior investigations have omitted this crucial information, focusing their historic research primarily on the British 49th Regiment. The data presented in this thesis offers a broader geographic, pan-nationalistic perspective on the possible infantrymen and militiamen who fought during the battle, including select Canadian militiamen from the Niagara region and the King’s 8th Regiment from Britain.

abstract: Master of Arts (MA)


title: A New Incremental Classification Approach Monitoring The Risk of Heart Disease

contributor:
Archer, Norman P.
Computing and Software

subject:
Computer Engineering
Computer Engineering

abstract:
Medical decision support systems are one of the main applications for data mining and machine learning techniques. Most of these systems involve solving a classification problem. Classification models can be generated by one of two types of learning classification algorithms: batch or incremental learning algorithms.

A batch learning algorithm generates a classification model trained by using the complete available data. Examples of batch learning algorithms are: decision tree C4.5 and multilayer perceptron neural network algorithms. However, an incremental learning algorithm generates a classification model trained incrementally through batches of training data. Examples of this are Learn++ and DWMV Learn++. Incremental learning algorithms are effective in problems in the healthcare domain where the training data become available periodically over time or where the size of database is very large. In the health care system, we consider heart disease a major cause death, and thus, it is a domain requiring attention. Early screening of patients for heart disease before they actually have its symptoms could therefore be an effective solution for decreasing the risk of this disease. Classification techniques can be employed to recognize patients who are at high risk of developing heart disease in order to send them for further attention or treatment by specialists.

This work proposes an incremental learning algorithm, called modified DWMV Learn++, for primary care decision support that classifies patients into high risk and low risk, based on certain risk factors. This system has been tested and proven to have good performance using real-world patient clinical records.

abstract: Master of Science (MSc)


title: Understanding Operational Stress Injury Support Services from a Veterans Perspective

contributor:
Greene, Saara
Sammon, Sheila

subject:
veteran
mental health
service provision
PTSD
militray
Social Work
Social Work

abstract:
Abstract

With the recent combat in Afghanistan, Post Traumatic Stress Disorder (P.T.S.D.) is once again in the public eye. With this it has sparked researchers interested in P.T.S.D. and the experiences of soldiers post combat. However, much of this literature has framed P.T.S.D. as abnormal psychology versus a normal reaction to extreme violence. Further, the literature has concentrated on P.T.S.D. and not explored Operational Stress Injuries. As well, it has been stated that there has been an influx of soldiers and combat veterans seeking social services. This is an exploratory study that examines the narratives of five veterans for their perspectives of operational injury support services. The research is based on an anti-oppressive interpretative social science framework and narrative based qualitative interviews with five veterans residing in Southern Ontario. The findings revealed stories of the veteran’s identity, the emotional impact of war, barriers to seeking treatment and facilitators to accessing services.

Each of these veterans spoke about their employment and culture and how this had an effect on seeking services. Many aspects of the veterans’ stories were comprised of stigma and the impact it had on seeking treatment. Condensed with stigma, the structural barriers exacerbate the soldier’s ability to seek culturally appropriate services in a timely fashion. Furthermore, these structural barriers do not solely impact the veterans in one area of their lives but have a ripple effect on all areas. Lastly, these veterans provided explicit service provisions that they believe would assist them and other veterans in the future. Not only do these men believe that individual support is important to them, but supporting their families also seems to be an important aspect of treatment. Even with individual treatment each veteran talked about the importance of peer support, whether it was too informal or formal, and the role of peer support seems vital in a holistic culturally appropriate treatment.

abstract: Master of Social Work (MSW)


title: LAUGHING IN CIRCLES: EXPLORING THE RELATIONSHIP BETWEEN POLITICALLY CORRECT DISCOURSES AND STAND-UP COMEDY IN TORONTO

contributor:
Yong, Kee
Rethmann, Petra
Anthropology

subject:
Carnival
humour
political correctness
performance
Bakhtin
Toronto
Anthropology
Social and Cultural Anthropology
Anthropology

abstract: It has been suggested that Canadian society increasingly promotes a rhetoric of tolerance, through the dissemination of multicultural and politically correct discourses. At the same time, there has been a growth in the popularity of performances that seemingly counters this national image; that of risqué stand-up comedy. This dissertation explores if an institutionalized rhetoric of multiculturalism and “PC”, popularized since the late 1980s, is pierced, protracted and parodied within risqué stand-up comedy while remaining confined within spatial and temporal boundaries. Furthermore, this relationship between comedy and multicultural and “PC” discourses illuminates the nature of power circulating within our dialogues about issues of discrimination in contemporary Canadian society. This thesis establishes that both stand-up comic performances and politically correct rhetoric share a carnivalesque nature that while degrades authorial discourses, is ultimately constrained within its self-definition.

abstract: Master of Arts (MA)


title: COMPLEX MODE CALCULATION BY FINITE ELEMENT METHOD

contributor:
Huang, Wei-Ping
Li, Xun
Kumar, Shiva
Electrical and Computer Engineering

subject:
Finite Element Method
Complex Mode
PML
Electromagnetics and photonics
Electromagnetics and photonics

abstract:
Optical waveguide is a very important component in numerous optical structures, devices and photonic circuits. With the rapid development of fabrication technologies, increasing integrated complexity and different materials characteristics, there is higher demand on high-index contrast waveguide with arbitrary cross section and anisotropic material, which indicates the need to develop an efficient, high-performance mode solver to analyze optical waveguides to reduce the fabrication cycle and total cost. Modeling and simulation methods, including Finite Difference Time-Domain (FDTD) method, Finite Element Method (FEM), Beam Propagating Method (BPM), Mode Matching Method (MMM) and Couple Mode Theory (CMT), etc, have been popular for years. Among those methods, FEM is a good and efficient method, especially for its superiority on arbitrary meshes.

In this thesis, both scalar and vectorial FEM mode solvers are implemented with an emphasis on dealing with the radiation and evanescent modes by enclosing the whole region with the Perfect Matched Layer (PML) and Perfect Reflecting Boundary (PRB). Thus, the unbounded and continuous radiation modes together with evanescent modes are replaced by what we called "complex modes", but still keeping the completeness and orthogonality properties.

abstract: Master of Applied Science (MASc)


title: A Century of Transitions in New York City's Measles Dynamics

contributor:
Earn, David
Bolker, Ben
Dushoff, Jonathan
Applied Mathematics

subject:
SIR model
measles
mathematical epidemiology
New York City
spectral analysis
Dynamic Systems
Dynamic Systems

abstract: Infectious diseases spreading in a human population can occasionally exhibit sudden transitions in their qualitative dynamics. Previous work has been very successful in predicting such transitions in New York City's measles incidence rates using the standard SIR model (susceptible, infected, recovered). This work relied on a dataset spanning 45 years, which we have extended to 93 years (1891-1984). We continue previous research in transition analysis on this larger dataset, and compare resonant and transient periods predicted to exist in NYC's measles incidence rates with those observed through a continuous wavelet transform of the data. We find good agreement between SIR predictions and observation, and in particular note the likely existence of previously unobserved hysteresis early in our new time-series.

abstract: Master of Science (MSc)


title: Anisotropic Superconductors and Elastic Impurity Scattering

contributor:
Carbotte, J.P.
Physics

subject: Physics Physics

abstract:
The thermodynamic properties of a number of simple metals in the superconducting state are calculated from the numerical solution of the isotropic Eliashberg equations on the imaginary axis and comparison is made with experiment. The functional derivatives of these properties with respect to change in the electron-phonon interaction are calculated and used in a detailed analysis of the interaction in superconducting Nb. Anisotropy in the electron-phonon interaction is also investigated numerically for some metals using a simple model for the anisotropy. The functional derivative in an anisotropic superconductor is found to be qualitatively different at low frequencies from that of an isotropic system. The difference is shown to be caused by the washing out of anisotropy by thermal phonons. Some comparison with experiment and with previous approximate solutions of the same model is made. For some quantities the previous approximate estimates of the effect of gap anisotropy are shown to be inadequate. A useful expression relating the amount of anisotropy with the impurity dependence of the critical temperature is developed independent of any such model or approximation.

Another calculation is done with a realistic calculated interaction for lead that includes anisotropy in the phonons and Fermi surface. An orthonormal basis set for the expansion of this interaction is enumerated and tested, but is found unnecessary for lead because the interaction is very close to separable. It is shown that the anisotropy in the interaction can be approximated by a very simple separable model without significantly affecting the thermodynamic properties. Also, the gap anisotropy on the imaginary axis is found to be identical to that of the gap edge at T=0 calculated on the real axis from the same interaction.

abstract: Doctor of Philosophy (PhD)


title: Star Formation in Low Mass Magnetized Cores: The Formation of Disks and Outflows

contributor:
Pudritz, Ralph E.
James Wadsley, Christine Wilson
Physics and Astronomy

subject: Star Formation

subject: Disk Formation

subject: Magnetohydrodynamics

subject: Protostellar Outflows

subject: Astrophysics and Astronomy

subject: Physical Processes

subject: Stars, Interstellar Medium and the Galaxy

subject: Astrophysics and Astronomy

abstract:
Protostellar discs are generally thought to drive molecular outflows and jets observed in star forming regions, but there has been some debate as to how they form. The details of the driving and collimation of outflows help determine how much mass is cleared out and how much energy is fed back into the surroundings. Recently it has been argued that the magnetic brake is so strong that early protostellar disks cannot form.

We have performed 3D ideal magnetohydrodynamic (MHD) simulations of collapsing Bonnor–Ebert spheres, employing sink particles within an AMR grid and using a cooling function to model radiative cooling of the gas. This allows us to follow the formation and early evolution of the accretion disc (2−8)×104 years further into the Class 0 phase of its evolution. We form a rotationally dominated disc with a radius of 100 AU embedded inside a transient, unstable, flattened, rotating structure extending out to 2000 AU. The inner disc becomes unstable to a warping instability due to the magnetic structure of the outflow, warping 30 deg with respect to the rotation–axis by the end of the simulation. The disc is unstable to a Parker instability and sheds magnetic loops, degrading the orientation of the mean threading field. This reduces and locally reverses the magnetic braking torque of the large scale field back upon the disc. The reduction of magnetic braking allows a nearly Keplerian disc to form and may be the key way in which low mass stellar systems produce rotationally dominated discs. We discuss the relevance of our disc misalignment concerning the formation of mis–aligned hot Jupiters.

Protostellar outflows are implicated in clearing mass from collapsing cores, and limiting the final mass of newly formed stars. The details of the driving and collimation of outflows help determine how much mass is cleared out and how much energy is fed back into the surroundings. The simulations generate outflows which are precessing, kinked, contain internal shocks and extend to a scale of 0.1 pc end–to–end. Our disc–wind theory describes magneto–centrifugal driving throughout the outflow bubble. The bulk properties of the outflow agree well with observations. The outflow has two components, a larger low speed wind (vr < 1.5 km/s) dominated by a toroidal magnetic field Bφ, and an inner centrifugally driven jet dominated by Bp with speeds up to 20 km/s. The ratio of mass flux from the disk surface com- pared to accretion in the disk is measured to be Mout/Min ∼ 0.1 from the inner component, whereas in the outer component Mout/Min ∼ 1.0. The jet is misaligned and precesses as the disc warps by 30 deg with respect to the z–axis. We measure star formation efficiencies of εcore = 0.63 (and growing), higher than theoretical predictions of εcore = 0.29−0.39 and observations εcore = 0.33.

These new results reported in this thesis, show that disks can form in strongly magnetized media, in agreement with the observations - and that outflows are not as efficient in clearing away collapsing gas as has been assumed in various theoretical models. Both of these results have important implications for disk formation, and the origin of the IMF, as described in this work.

abstract: Doctor of Philosophy (PhD)


title: BRAUER-KURODA RELATIONS FOR HIGHER CLASS NUMBERS

contributor:
Kolster, Manfred
Nicas, Andrew J.
Valeriote, Matthew A.
Mathematics

subject:
Number Theory
Dedekind Zeta Function
motivic wild kernel
Brauer-Kuroda relations
motivic cohomology
Number Theory
Number Theory

abstract: Arising from permutation representations of finite groups, Brauer-Kuroda relations are relations between Dedekind zeta functions of certain intermediate fields of a Galois extension of number fields. Let E be a totally real number field and let n ≥ 2 be an even integer. Taking s = 1 − n in the Brauer-Kuroda relations then gives a correspondence between orders of certain motivic and Galois cohomology groups. Following the works of Voevodsky and Wiles (cf. [33], [36]), we show that these relations give a direct relation on the motivic cohomology groups, allowing one to easily compute the higher class numbers, the orders of these motivic cohomology groups, of fields of high degree over Q from the corresponding values of its subfields. This simplifies the process by restricting the computations to those of fields of much smaller degree, which we are able to compute through Sage ([30]). We illustrate this with several extensive examples.

abstract: Master of Science (MSc)


title: Multitarget Tracking Using Multistatic Sensors

contributor:
Kirubarajan, T.
I. Bruce, S. Sirouspour
Electrical and Computer Engineering

subject: target tracking

subject: multipath

subject: data association

subject: multiframe assignment

subject: multipath PCRLB

subject: passive coherent location

subject: bias removal

subject: transmitters of opportunity

subject: multipath tracking

subject: Applied Statistics

subject: Multi-Vehicle Systems and Air Traffic Control

subject: Navigation, Guidance, Control and Dynamics

subject: Probability

subject: Signal Processing

subject: Systems and Communications

subject: Applied Statistics

abstract:
In this thesis the problem of multitarget tracking in multistatic sensor networks is studied. This thesis focuses on tracking airborne targets by utilizing transmitters of opportunity in the surveillance region. Passive Coherent Location (PCL) system, which uses existing commercial signals (e.g., FM broadcast, digital TV) as the illuminators of opportunity for target tracking, is an emerging technology in air defence systems. PCL systems have many advantages over conventional radar systems such as low cost, covert operation and low vulnerability to electronic counter measures.

One of another opportunistic signals available in the surveillance region is multipath signal. In this thesis, the multipath target return signals from distinct propagation modes that are resolvable by the receiver are exploited. When resolved multipath returns are not utilized within the tracker, i.e., discarded as clutter, potential information conveyed by the multipath detections of the same target is wasted. In this case, spurious tracks are formed using target-originated multipath measurements, but with an incorrect propagation mode assumption. Integrating multipath information into the tracker (and not discarding it) can help improve the accuracy of tracking and reduce the number of false tracks.

In this thesis, these opportunistic measurements, i.e., commercial broadcast signals measurements in PCL tracking and resolvable multipath target return measurements in multipath assisted tracking are exploited. We give the optimal formulations for all of the above problems as well as the performance evaluations using PCRLB. Simulation results illustrate the performance of the algorithms.

abstract: Doctor of Philosophy (PhD)


title: CHARACTERIZING CBID AND BAX BINDING TO SUPPORTED LIPID BILAYERS WITH SINGLE MOLECULE RESOLUTION

contributor:
Fradin, Cecile
Andrews, David W.
Rheinstadter, Maikel
Biochemistry

subject:
Apoptosis
confocal
FCS
FIDA
fluorescence
membrane
Biochemistry
Biophysics
Molecular Biology
Biochemistry

abstract: Bid and Bax are proteins that play a key role in mitochondrial outer membrane permeabilization during apoptosis. Elucidating the molecular mechanisms regulating the function of these proteins is essential to understanding how apoptosis is altered in diseases and for developing therapies. In this thesis, a mitochondria-like supported lipid bilayer (SLB) system is established and used to characterize the membrane binding behaviour of cBid and Bax with single molecule resolution. The formation of SLBs on mica substrate was characterized and lipid diffusion in the plane of the membrane was measured by fluorescence correlation spectroscopy to be 2-6 µm2/s depending on the fluorescent probe used. The binding of cBid to lipids in supported bilayers occurred with an apparent KD of 121 µM. Combining fluorescence intensity distribution analysis and confocal imaging, cBid binding to SLBs revealed 2 populations of molecules in the membrane: monomers which primarily diffuse in the plane of the membrane and higher order oligomers which are predominantly immobile. In the presence of Bax, the distribution of cBid molecules shifted towards more mobile protein and smaller complexes, while in the presence of Bcl-XL an opposite shift towards immobile protein and larger complexes occurred. This suggests a mechanism for cBid function where the mobility of cBid in the membrane and its oligomeric state can alter its propensity to activate Bax and influence the progression of apoptosis. Bax binding to SLBs was also observed as two populations of mobile and immobile protein. Both populations comprised mostly Bax monomers. Immobile Bax oligomers up to decamers were also observed, and the formation of higher Bax oligomers appeared to be a cooperative processes once a dimer was formed. In comparison to Bax binding to liposomal membranes, its affinity for SLBs appeared to be 40-fold less with a measured KD of 381 µM.

abstract: Master of Science (MSc)


title: THE JUSTICE OF URBAN CHANGE: ASSESSING THE SUSTAINABILITY AND DISTRIBUTIVE JUSTICE OF URBAN CHANGE USING AN INTEGRATED URBAN MODEL

contributor:
Kanaroglou, Pavlos
Scott, Darren
Geography and Earth Sciences

subject:
Integrated Urban Model
Distributed Justice
Residential Development
Job Sprawl
School Closures
Vulnerable Population
Human Geography
Human Geography

abstract: The importance of citizen’s psychological need for community, amenities, and the feeling of equitable distribution of the varied impacts from urban change are gaining recognition as important factors in evaluating sustainable urban change. The inclusion of indicators that capture the equitable distribution of urban change impacts are a rare addition to the vast list of sustainability indicator sets available to researchers. Rarer still is the application of Integrated Urban Models (IUMs) and sustainability indicators in assessing the sustainability of land use and transportation policies which impact not only the form and structure of cities, but also the health and wellbeing of the city residents. Using three land use scenarios relevant to the study area: the City of Hamilton, scenarios which simulate alternative residential density patterns, the suburbanization of employment and the closure of elementary and secondary schools are projected into the medium term future using an integrated GIS-based model for simulating the consequences of demographic changes and population ageing on transportation (IMPACT), a sustainability indicator module and a set of indicators measuring the degree to which the urban change is just. The sustainability values generated from the use of IMPACT and SUSTAIN offer valuable insight to the literature related to each scenario. More importantly, the justice indicators add value information as to the impact of urban change on vulnerable population groups. The combination of IMPACT and SUSTAIN offers new avenue and method for future research on the sustainability of urban change.

abstract: Master of Arts (MA)


title: N400 But No P600 With Semantic Anomalies

contributor:
Service, Elisabet
Connolly, John
Moro, Anna
Cognitive Science of Language

subject:
language comprehension
N400
P600
ERP
RSVP
syntax
Syntax
Syntax

abstract: Event-related potentials (ERPs) have been used extensively in the scientific research of cognitive processing such as language comprehension. Specific responses, such as the negativity called N400 (Kutas & Hillyard, 1980), have in the literature typically been associated with semantic violations in sentences. Another electrophysiological response, the positive P600 waveform, has mostly been associated with syntactic and morphological violations. However, recently, the P600 has been reported also in connection with semantic violations (Kuperberg et al, 2003; van Herten, 2004; Osterhout, 2004). The present research further explores the neurophysiological correlates of processing sentences with semantic and morpho-syntactic violations. It tests the functional interpretations of the P600 component, which has been proposed to reflect syntactic error detection, context updating, or syntactic reanalysis or repair. I contrasted semantic and syntactic possessive violations. The semantic violation conditions (i.e. The mother borrowed the car’s daughter for work yesterday), morphosyntactic violations (i.e. The mother borrowed the daughter car for work yesterday) and double violation sentences (i.e. The mother borrowed the car daughter for work yesterday) were derived from the control condition, (i.e. The mother borrowed the daughter’s car for work yesterday). I explored whether the P600 component may index more general processes than ones related to syntactic error detection. An N400 was seen to our semantic manipulation, i.e. The mother borrowed the car’s daughter for work yesterday. However, none of the conditions produced a P600.

abstract: Master of Science (MSc)


title: The Climatic Difference Principle

contributor:
Igneski, Violetta
Wendling, Karen
Philosophy

subject:
difference principle
climate change justice
Rawls
Philosophy
Philosophy

abstract:
I seek to answer a specific question of justice: namely, how to find an equitable division of the Earth’s capacity to absorb greenhouse gases, here termed as the global carbon sink. The dominant approach to date has been a variation of equal per-capita emissions. My aim is to expand on the Rawlsian legacy by presenting a viable alternative to the dominant approach in the form of an adaptation of Rawls’s difference principle in the form of a climatic difference principle. The climatic difference principle takes the conceptual idea behind the difference principle – of justifying inequalities so long as they result in a compensating benefit for everyone, with a particular concern for the least advantaged – and applying it to the problem of how to divide the global carbon sink.

I begin with a critique of the dominant approach in order rectify the lack of critical scrutiny that the scheme has enjoyed in order to illustrate that the scheme fails for two reasons: first, it violates the ideal that it purports to promote; second, the reasons to support the proposal rest on shallow, rather than deep, reasons alone. Next, I engage in a critique of past attempts to globalize the difference principle, for if it were possible to merely globalize the difference principle, we wouldn’t need a distinct principle to guide emissions allocations.

The climatic difference principle itself takes the distributive outcomes of equal per-capita emissions, as measured on the Human Development Index (HDI), as a baseline to judge alternative schemes. My conjecture is that the way emissions are used will have an effect on the amount of net benefits that we can derive per unit of the global carbon sink. Shares of the global carbon sink can be used more or less efficiently, and incentives in the form of a greater share of the sink will spur technological innovation. However, Rawls was correct to insist that the most efficient scheme is not necessarily just.

A division of the global sink is considered just if we can compensate everyone (in particular the least advantaged) for accepting an unequal share. Specifically, when judged by improvements from the baseline created by the distributive outcomes of equal per-capita emissions, as measured on the Human Development Index (HDI). In order to realize the distributive obligations of the climatic difference principle, a green-technology transfer program will be advanced along with other forms of aid and compensation.

abstract: Master of Philosophy (MA)


title: Canadian Mining and Labour Struggles in Mexico: The Challenges of Union Organizing and the Weaknesses of Corporate Social Responsibility

contributor:
Wells, Donald
Lewchuk, Wayne
Mills, Suzanne
Labour Studies

subject:
Mexico
mining
labour
unions
corporate social responsibility
resource extraction
Work, Economy and Organizations
Work, Economy and Organizations

abstract: Focusing on a case study of a union organizing effort at the La Platosa mine in northern Mexico from 2009-2012, this paper studies the challenges facing labour activism at Canadian mining companies in Mexico within the context of the North American Free Trade Agreement. The positions of the Mexican and the Canadian governments in relation to contemporary workers’ struggles in Mexico’s mining sector are considered, particularly the latter’s adoption of a ‘corporate social responsibility’ approach to addressing the activities of Canadian extractive firms abroad. By studying the outcome of the request for mediation filed by La Platosa miners with the Canadian government’s Extractive Sector CSR office in 2011 and evaluating the evolution of this government’s policy approach to extractive companies abroad since 2009, we find that CSR as practiced by the Canadian government has been ineffective at mitigating abusive practices by Canadian mining companies in Mexico and that an alternate outcome is not to be expected under existing policy structures. The relative strengths and weaknesses exhibited during labour organizing at the La Platosa mine are evaluated to find both locally specific and more broadly applicable strategies which could be applied to union renewal, both by workers employed under NAFTA’s transnational sector, and by the general labour movement.

abstract: Master of Arts (MA)


title: IMPACT OF GASTROINTESTINAL AND SKIN BARRIER DISRUPPTION ON SENSITIZATION TO PEANUT

contributor:
Jordana, Manel
Elena Verdu, Susan Waserman
Health Sciences

subject:
Peanut
Allergy
Skin
Sensitization
Neonatal
Epicutaneous
Medicine and Health Sciences
Medicine and Health Sciences

abstract:
It has been suggested that environmental factors substantially contribute to the increased prevalence of peanut allergy in industrialized countries. Specifically, the role of disrupted barrier integrity in the gastrointestinal tract has been implicated in the development of food allergy. The use of non-steroidal anti-inflammatory drugs (NSAIDs), which increase intestinal permeability, for the treatment of pain and fever is prevalent in industrialized countries. Therefore, the first aim of this study was to determine whether treatment with indomethacin, a prototypical NSAID, would act in an adjuvant like manner to facilitate sensitization to co-administered peanut protein. Furthermore, we investigated whether indomethacin increases susceptibility to anaphylaxis following oral challenge with peanut in sensitized mice.

First, a short model of cholera toxin-mediated sensitization to peanut was developed. Mice were given 1 mg of peanut protein and 5 μg of cholera toxin by oral gavage for 10 consecutive days. This resulted in a robust anaphylactic response and increased peanut-specific IgG1, but not IgE, two weeks following treatment. Mice exposed to peanut during a 10-day treatment with indomethacin (5 mg/kg on alternating days or 3.5 mg/kg daily) did not develop peanut-specific immunoglobulins or anaphylaxis following systemic challenge with peanut protein. Furthermore, treatment with two 5 mg/kg doses of indomethacin 24 and 1 hour before oral challenge did not facilitate anaphylaxis in peanut-sensitized mice. Therefore, we concluded that NSAID treatment is unlikely to play a role in the increased prevalence of peanut allergy, and that NSAID treatment does not increase susceptibility to peanut-induced anaphylaxis in sensitized mice.

The second part of this study aimed to develop a short model of epicutaneous sensitization, and address the impact of epicutaneous exposure to peanut during infancy. We investigated the role of site of exposure, duration of exposure, epidermal integrity, strain and age in epicutaneous sensitization. 10 consecutive days of epicutaneous exposure to 20 μg of peanut protein through tape stripped skin induced robust anaphylaxis following i.p. challenge. Neither 7 days of exposure through tape stripped skin, nor 10 days of exposure through intact skin facilitated sensitization. The strength of sensitization was strain-dependent; peanut-specific IgG1 was increased equally in both C57BL/6, and BALB/c mice, and to a greater extent in C3H/HeJ mice. Peanut-specific IgE was increased in both BALB/c and C3H/HeJ mice three weeks following peanut exposure. Epicutaneous exposure beginning one day after birth did not facilitate the development of either peanut-specific IgE or IgG1 in BALB/c mice, or anaphylaxis following systemic challenge. Beginning exposure at 2 weeks of age resulted in peanut-specific IgE and IgG1 production, as well as a robust anaphylaxis following i.p. challenge. Therefore, the development of peanut allergy through epicutaneous exposure is age dependent, and exposure during the neonatal period results in a hyporesponsive response.

abstract: Master of Science (MSc)


title: Charge-Coupled Devices and Computers in Optical Remote On-Line Tracking of Human Locomotion

contributor:
Milner, M.
Electrical Engineering

subject:
Electrical and Electronics
Electrical and Electronics

abstract:
The recording, measurement and study of kinesiological aspects of human locomotion is of great importance to rehabilitation engineers and clinicians. Clinical needs which stimulated the development of the system designed include the design and evaluation of prosthetic and orthotic devices; follow-up of the dynamic performance of patients undergoing therapeutic or surgical treatment such as major joint replacement; biofeedback relating to human movements and facilitated by on-line displays; general use in studying human movements. A list of importance factors for such a system should take cognisance of the following: -The patient or the subject should be influenced as little as possible by the instrumentation set-up. -For comprehensive data collection several body points have to be recorded simultaneously. -Spatial information is required in three dimensions. -Visual real-time (or virtually so) displays of body movements are produced. -Data storage and processing with inexpensive mini- or micro-computers should be possible.

This thesis deals with a solution which addresses itself to the aspects outlined above.

The work constitutes a significant advance in, and realization of, a 3-dimensional optoelectronic camera system embodying recently available charge-coupled devices of the area-image-sensor variety. The cameras are interfaced to a minicomputer and appropriate software (programmes) have been developed to permit relevant processing and achieve pertinent displays of the kinesiological data acquired. A major concern was to generate results which are of substantial use to clinicians. This "clinical digestibility" feature has been incorporated wherever possible.

The essential specifications alluded to above have been met and analyses are incorporated. The thesis embraces detailed information to enable developmental work on further prototype camera systems to be undertaken. In its present form, the system appears to meet the essential needs, and future refinements such as implementing larger sensors and expanding the software routines to produce a wider variety of analyses and display possibilities are indicated. Recordings allied with a variety of locomotion disorders have been made. These include hemiplegic gait.

abstract: Doctor of Philosophy (PhD)


title: GLUCOSE SUPPLEMENTATION AND MEASURES OF OXIDATIVE STRESS IN PATIENTS WITH GLYCOGEN PHOSPHORYLASE DEFICIENCY (MCARDLE’S DISEASE).

contributor:
Tarnopolsky, Mark
Medical Sciences

subject: McArdles disease

subject: oxidative stress

subject: exercise

subject: glucose supplementation

subject: Biochemical Phenomena, Metabolism, and Nutrition

subject: Medical Nutrition

abstract: Objective: We evaluated the potential effect of oral glucose supplementation on: (1) exercise performance and tolerance, (2) the concentrations of plasma uric acid and ammonia (NH3) and (3) blood plasma markers of oxidative stress in patients with McArdle’s disease (MCD) after non-ischemic forearm exercise testing (non-ischemic forearm exercise test). Methods: Blood samples and exercise performance measures were performed on from 16 patients with MCD and 17 control subjects (CON) matched for age, sex and physical activity status. Subjects performed 2 exercise bouts 30 minutes apart and received oral glucose or placebo supplementation between tests. Blood samples were analyzed for concentrations of 8-isoprostanes (8-ISO), malondialdehyde (MDA) and total anti-oxidant capacity (TEAC). Exercise performance was assessed using a handgrip dynamometer to measure force of contraction over time. Exercise tolerance was assessed based on subject’s self-reported perception of pain and perception of exertion during exercise. Results: MCD was associated with greater fatigue, perceived pain, perceived exertion, and higher uric acid during non-ischemic forearm exercise test (P < 0.05), and higher concentrations of plasma NH3 post exercise (P < 0.05). Glucose did not influence plasma uric acid or NH3 and had no effect on exercise measures in MCD patients. Baseline plasma markers of oxidative stress were not different between MCD patients and CON; however, MCD patients who ingested glucose between non-ischemic forearm exercise tests had lower plasma 8-ISO concentrations (P < 0.05). CON who ingested glucose between non-ischemic forearm exercise tests had lower plasma 8-ISO concentrations (P < 0.05) at +1 min post exercise compared to initial non-ischemic forearm exercise test. The TEAC of control subjects was lower following non-ischemic forearm exercise test (P < 0.05), with no change in MCD patients. Conclusion: Glucose may have a protective effect on oxidative stress following exercise that may be due to attenuated flux through xanthine oxidase.

abstract: Master of Science (MSc)


title: “SERVE YOURSELF AND YOUR COUNTRY”: THE WARTIME AND HOMECOMING EXPERIENCES OF AMERICAN FEMALE MILITARY NURSES WHO SERVED IN THE VIETNAM WAR

contributor:
Streeter, Stephen
Balcom, Karen
Wright, David
History

subject: women; military; Vietnam war; nurses; armed forces; American

subject: United States History

subject: United States History

abstract:
Between 1964 and 1975, approximately 7,500 to 11,000 American military women served in the Vietnam War. They served in many roles – they worked as air traffic controllers, dieticians, physiotherapists, clerks, and cryptographers – but the bulk of American women who went to Vietnam served as military nurses with the Army, Navy, and Air Force Nurse Corps. This dissertation explores the wartime and homecoming experiences of female nurse veterans whose Vietnam experiences have been largely ignored or minimized by historical accounts of the war. By refashioning the narrative of the war to include women, this study challenges cultural constructions of war as an exclusively male sphere, and in doing so offers a more sophisticated understanding of both men’s and women’s Vietnam service.

In Vietnam, American women risked their lives for their country. Motivated by a blend of patriotism, humanitarianism, professional advancement, and educational opportunity, female nurses volunteered for war at a time when many young men sought to evade military service. Yet the women who served have been consistently denied the rewards of their sacrifice. After the war, sexist attitudes about who is eligible for the privileges which accompany military service led the VA to routinely deny veterans entitlements including health care and disability pensions to female military nurses. Efforts to memorialize the war, through their focus on male veterans’ experience, relegated women’s service in Vietnam to the periphery of public memory. Based primarily on oral history interviews with 29 female military nurses who served in the war, this dissertation reveals women’s agency through an exploration of their responses to these and other gendered challenges associated with their military service, and exposes the connection between public memory and women’s access to the benefits bestowed upon martial citizens.

abstract: Doctor of Philosophy (PhD)


title: Tardigrade Phylogenetic Systematics at the Family Level Using Morphological and Molecular Data

contributor:
Stone, Jonathon R.
Golding, Brian G.
Evans, Ben
Biology

subject:
Tardigrada
phylogeny
systematics
Bioinformatics
Evolution
Other Ecology and Evolutionary Biology
Bioinformatics

abstract: Tardigrade phylogenetic systematic analyses have been conducted using morphological and molecular data; however, incongruencies between results obtained independently with the data types have been found. This thesis contains new morphological and molecular phylogenetic systematic analyses of tardigrades at the family level, building on previous research. The first part involves morphological data, the second part involves molecular data, and the third part involves combined morphological and molecular data. The morphological data include 50 characters for 15 tardigrade families. The molecular data include updated 18S rRNA, 28S rRNA, and COI gene sequences, in two sets; the first set provides the most-extensive representation of tardigrade families and comprises 18S rRNA sequences; the second set provides the most-complete representation of molecular data per species, where available, and involves the concatenation of 18S rRNA, 28S rRNA, and COI gene sequences. Finally, the combined data involves a supermatrix containing morphological and molecular data. The analyses are used to test results from previous systematics research and to contribute more information to tardigrade systematics.

abstract: Master of Science (MSc)


title: Eukaryotic and Prokaryotic Sources of Colonic Hydrogen Sulfide Synthesis

contributor:
Wallace, John L.
Huizinga, Jan
Bercik, Premek
Medical Sciences

subject:
Inflammation
Mucosal Defense
Ulcer
Repair
Bacteria
Microbiota
Gastroenterology
Gastroenterology

abstract:
Hydrogen sulfide (H2S) is an important modulator of many aspects of digestive function, both in health and disease. Colonic tissue H2S synthesis increases markedly during injury and inflammation and contributes to resolution. Some of the bacteria residing in the colon also produce H2S. The extent to which bacterial H2S synthesis contributes to what is measured as colonic H2S synthesis is not clear. When comparing conventional and germ-free mice we found no differences in colonic H2S synthesis. Furthermore, we found that colonic H2S synthesis is markedly increased when colonic tissue is inflamed, and, in proportion to the extent of inflammation, however fecal H2S synthesis does not change. Finally, rats fed a B vitamin-deficient diet for 6 weeks exhibited significantly diminished colonic H2S synthesis, but fecal H2S synthesis was not different from that of rats on the control diet. Our results demonstrate that H2S production by colonic bacteria does not contribute significantly to what we measure as colonic tissue H2S production.

In another study, the contributions of three enzymatic pathways to colonic H2S synthesis were determined in tissues taken from healthy rats and rats with colitis. The ability of colonic tissue to inactivate H2S was also determined. The majority of increased H2S synthesis, in both healthy and inflamed tissue, was derived via a pyroxidal-5’-phosphate-independent pathway. Ulcerated mucosal tissue accounted for the greatest levels of H2S synthesis, and the extent of granulocyte infiltration into the tissue did not appear to be a significant determinant of the levels of H2S production. Inactivation of H2S by colonic tissue occurred rapidly, but was significantly reduced in ulcerated colonic tissue from rats with colitis. Damage to colonic tissue appears to be the major stimulus for enhanced H2S synthesis. Together, the increased production and decreased inactivation of H2S may contribute to promoting resolution of inflammation and repair of damaged colonic tissue.

abstract: Master of Science (MSc)


title: Simulation of Time-Dependent Neutron Populations for Reactor Physics Applications Using the Geant4 Monte Carlo Toolkit

contributor: Engineering Physics and Nuclear Engineering

subject:
Monte Carlo
reactor physics
nuclear engineering
stochastic
time-dependent
Geant4
Engineering Physics
Nuclear
Nuclear Engineering
Engineering Physics

abstract:
When the material or geometry of a reactor varies with time, the neutron flux will respond in the form of a reactor transient. These transients can occur during normal operations when control rods are moved or the reactor is refuelled (CANDU). During a reactor accident, the transient response is especially important because the reactor properties vary quickly with large amplitudes. Therefore, better understanding these conditions allows for improved identification, prevention and mitigation of reactor transients. However, current nuclear simulation codes are generally limited in their ability to model transient behaviour.

The NStable code was created to model time-dependent neutron populations in multiplying mediums using the Geant4 Monte Carlo toolkit. The neutron population is allowed to evolve in time, but is periodically renormalized so that the total number of neutrons is constrained within a manageable range. This ensures that the simulation is viable even in highly sub- or supercritical environments. Since Geant4 was not intrinsically designed to track a neutron population over "long" time periods (up to 10 s), the population renormalization mechanisms needed to be created and integrated with Geant4. Additionally, nuclear reactor analysis functionality was added to calculate important quantities such as keff.

The NStable code was validated using three established nuclear simulation codes: MCNP 5, DRAGON 3.06J, and TART 2005. The validation cases compared spatial distributions and criticality estimates for either homogeneous spheres (uranium-235 or a uranium-heavy water mixture) or the standard CANDU 6 lattice cell. For all three systems, the criticality estimates in NStable agreed with the appropriate validation code within 10 mk (TART for the spheres and DRAGON for the CANDU 6 lattice). Finally, the NStable code was also used to simulate a temperature transient in a UHW sphere where the temperature linear increased by 700 K over 50 ms. In response to the increasing temperature, keff decreased by 100 mk over the same period. In the future, transient modelling in NStable should be investigated further to reproduce actual experimental results, and to couple NStable with a thermohydraulics code to simulate a full transient response.

abstract: Master of Applied Science (MASc)


title: MODEL-BASED COST-CONSEQUENCE ANALYSIS OF POSTOPERATIVE TROPONIN T SCREENING IN PATIENTS UNDERGOING NONCARDIAC SURGERY

contributor: Clinical Health Sciences (Health Research Methodology)

subject: economic evaluation; cost-consequence analysis; troponin T; noncardiac surgery; screening

subject: Anesthesiology

subject: Cardiology

subject: Clinical Epidemiology

subject: Health Services Research

subject: Surgery

subject: Anesthesiology

abstract:
Introduction: Globally, more than 200 million patients undergo major non-cardiac surgery each year and more than 10 million patients will be exposed to postoperative myocardial ischemia, a condition strongly associated with 30-day mortality. The majority of these events go undetected without postoperative Troponin screening. Methods: We conducted a model-based cost-consequence analysis comparing a postoperative Troponin T screening vs. standard care in patients undergoing noncardiac surgery. In a first model, we evaluated the incremental number of detected perioperative myocardial infarctions and the incremental costs. A second model assessed the effect of the screening and consequent treatment on 1-year survival and the related cost. Model inputs based on the Vascular events In Non-cardiac Surgery patIents cOhort evaluatioN (VISION) Study, a large international cohort. We run probability sensitivity analyses with 5,000 iterations. We conducted extensive sensitivity analyses.

Results: The cost to avoid missing an event amounted to CAD$ 5,184 for PMI and CAD$ 2,983 for isolated Troponin T. The cost-effectiveness of the postoperative Troponin screening was higher in patients’ subgroups at higher risk for PMI, e.g. patients undergoing urgent surgery. The incremental costs at 1 year of a postoperative PMI screening by 4 Troponin T measurements were CAD$ 169.20 per screened patient. The cost to prevent a death at 1 year amounted to CAD$ 96,314; however, there was relevant model uncertainty associated with the efficacy of the treatment in the 1-year model.

Conclusion: Based on the estimated incremental cost per health gain, the implementation of a postoperative Troponin T screening after noncardiac surgery seems appealing, in particular in patients at high risk for perioperative myocardial infarction. However, decision-makers will have to consider it in terms of opportunity costs, i.e. in relation to the cost-effectiveness of other potential programs within the broader health care context.

abstract: Master of Science (MSc)


title: SPECTRAL ENGINEERING VIA SILICON NANOCRYSTALS GROWN BY ECR-PECVD FOR PHOTOVOLTAIC APPLICATIONS

contributor:
Kleiman, Rafael
Mascher, Peter
Knights, Andrew
Engineering Physics

subject:
Down-shifting
photoluminescence
silicon nanocrystals
PECVD
quantum efficiency
Nanoscience and Nanotechnology
Semiconductor and Optical Materials
Nanoscience and Nanotechnology

abstract:
The aim of third-generation photovoltaics (PV) is ultimately to achieve low-cost, high-efficiency devices. This work focused on a third-generation PV concept known as down-shifting, which is the conversion of high-energy photons into low-energy photons which are more useful for a typical solar cell. Silicon nanocrystals (Si-NCs) fabricated using electron-cyclotron resonance plasma-enhanced chemical vapour deposition (ECR-PECVD) were studied as a down-shifting material for single-junction silicon cells. A calibration was done to determine optimal deposition parameters for Si-NC formation. An experiment was then done to determine the effect of film thickness on emission, optical properties, and photoluminescence quantum efficiencies.

Photoluminescence (PL) peaks varied depending on the stoichiometry of the films, ranging from approximately 790 nm to 850 nm. Variable-angle spectroscopic ellipsometry was used to determine the optical constants of the Si-NC films. The extinction coefficients indicated strong absorption below 500 nm, ideal for a down-shifting material. Transmission Electron Microscopy (TEM) was used to determine the size, density, and distribution of Si-NCs in two of the films. Si-NCs were seen to have an average diameter of approximately 4 nm, with larger nanocrystals more common near the surface of the film. A density of approximately 105 nanocrystals per cubic micron was approximated from one of the TEM samples.

The design and implementation of a PL quantum efficiency measurement system was achieved, using an integrating sphere to measure the absolute efficiency of Si-NC emission. Internal quantum efficiencies (IQE) as high as 1.84% and external quantum efficiencies (EQE) of up to 0.19% were measured. The EQE was found to increase with thicker films due to more intense photoluminescence; however the IQE remained relatively independent of film thickness.

abstract: Master of Applied Science (MASc)


title: CHARACTERIZATION OF MARCO-MEDIATED ENDOCYTOSIS

contributor: Medical Sciences (Molecular Virology and Immunology Program)

subject: endocytosis

subject: scavenger receptors

subject: MARCO

subject: clathrin-mediated endocytosis

subject: Biological Phenomena, Cell Phenomena, and Immunity

abstract:
Class A scavenger receptors are multifunctional transmembrane glycoproteins that mediate macrophage functions like phagocytosis and endocytosis. The macrophage receptor with collagenous structure (MARCO) is one such receptor. It has been shown that the extracellular cysteine-rich domain of MARCO is responsible for ligand binding, but the role of the cytoplasmic domain in ligand uptake is unclear. The aim of the studies presented in this thesis is to characterize the role of the cytoplasmic domain of MARCO and to characterize the molecular pathway of MARCO-mediated endocytosis.

Full-length human MARCO (hMARCO) and Δ1-34hMARCO, which lacks the first thirty-four amino acids were created in order to determine whether amino acids 1-34 contained residues required for receptor internalization and surface expression. The constructs were stably expressed in HEK293T cells and found to have similar levels of surface expression and same rate of internalization without ligand. Interestingly, hMARCO, but not Δ1-34hMARCO, surface expression was up-regulated upon ligand incubation.

In order to ascertain the importance of clathrin, dynamin and actin in MARCO-mediated endocytosis, specific endocytic inhibitors were used. MARCO-mediated ligand uptake was inhibited when clathrin and actin polymerization and, dynamin functions were impaired by these inhibitors. Furthermore, ligand uptake by Δ1-34hMARCO-expressing HEK293T was insensitive to inhibitors of clthrin and dynamin but not inhibitors of actin.

In conclusion, MARCO mediates endocytosis via a clathrin-mediated, dynamin-dependent pathway that involves actin. Amino acids 1-34, are required clathrin and dynamin but not actin functions during MARCO-mediated endocytosis. Additionally, amino acids 1-34 might also be important for MARCO recycling but not receptor internalization or surface expression.

abstract: Master of Science (MSc)


title: Strategies to Investigate the Role of EpCAM in Cancer Stem Cells of Breast Cancer Cell Lines

contributor:
Hassell, John A.
Trigatti, Bernardo
Karen Mossman, Jonathan Bramson
Biochemistry

subject:
Breast Cancer
Cancer Stem Cell
EpCAM
EMT
Biochemistry
Molecular Biology
Molecular genetics
Biochemistry

abstract: Based on the cancer stem cell (CSC) model, tumors develop as a hierarchy, much like normal tissue. At the apex, CSCs are capable of self-renewal and differentiating into non-tumorigenic cells that form the bulk of the tumor. CSCs have been isolated for many types of cancer based on cell surface marker expression. For instance in human breast carcinoma, the CD44+ CD24-/low EpCAM+ population are enriched in CSCs. These cells are more resistant to traditional chemo and radiation therapy relative to the bulk of the tumor. As such, many believe CSCs to be responsible for relapse and metastasis events. Hence, a more targeted therapy towards breast CSCs can prove to be very effective. EpCAM has been shown to be a reliable, albeit not exclusive, marker of breast CSCs. A more thorough understanding of EpCAM’s function can provide new angles for designing therapeutic agents. Originally thought to be a mere adhesion molecule, EpCAM is now known to derive a signalling pathway that promotes transcription in its target genes. We aimed to provide further insight into this novel pathway, by manipulating EpCAM’s expression and function in MCF7 breast cancer cell line. We designed a dominant negative allele of the EpCAM protein to hinder the activity of the endogenous EpCAM. However, this transgene offered no significant effect on our cell line. Furthermore, we used RNA interference technology to reduce EpCAM expression. The introduction of the EpCAM short hairpin RNA constructs into our cell line had inhibitory effects on transcription reporter expression, cellular growth, adherent colony and unattached sphere formation. The inhibition of EpCAM in MCF7 spheres was followed by signs of cell death, differentiation and an epithelial mesenchymal transition process. Sphere cultures are used because they are enriched in cancer stem cells. The adverse effects of EpCAM inhibition in MCF7 spheres provides further evidence as to the role of this protein in cancer stem cells.

abstract: Master of Science (MSc)


title: Geomorphology of the North Karst, South Nahanni River Region, Northwest Territories, Canada

contributor:
Ford, D. C.
Geography

subject: Geography Geography

abstract:
First investigated on the ground in June 1972, the Nahanni karst of northern Canada is the most complex karst terrain yet reported from high latitudes. It is centered at 61°28' N, longitude 124°05' W and lies within the zone of discontinuous permafrost. Mean annual temperature is 24°F and mean total precipitation 22.3 inches. Principal karst forms are fracture-located karst streets and irregularly-shaped closed depression called karst platea which may be up to 600 feet in depth. Platea often contain karst towers which are residuals of wall recession. Vertical-walled pond dolines up to 120 feet deep are common in bare karst areas while subjacent karst collapse, subsidence and suffosion depressions occur on marginal shale- and drift-mantled surfaces. Three small poljes have been identified, two produced entirely by solution, the other a structural form. These are periodically inundated. There are several peripheral fluvial canyons up to 3,000 feet deep that are blocked by glacial drift and which presently drain underground. Similarity in the hydrogeological properties of Nahanni Formation limestones at a variety of scales has led to the development of morphologically-identical karst forms which range in size from inches up to hundreds of feet. Furthermore, many of these landforms are part of a developmental sequence that at one scale links vertical-walled dolines, karst streets, platea and poljes; and at another links solution pits, grikes and joint hollows on limestone pavements. The evidence suggests that poljes form by the coalescence of dolines and uvalas just as Cvijic suggested in 1918. In attempting to explain the almost "tropical" nature of the sub-arctic Nahanni karst landform assemblage, a number of facts are of importance.

(a) The Nahanni Formation limestones have been highly warped and intensively fractures during the past one million years. Open fractures have encouraged karstification by allowing easy movement of water underground. Warping has provided the relief necessary for the development of solutional forms with a distinct vertical component.

(b) The karst can not be considered relict because it was glaciated during the Pleistocene. In addition the hydrological activity in it today is comparable with that in many humid tropical karst areas.

(c) Solutional denudation rates governed by aspects of surficial and bedrock geology may in some localized areas be equivalent to rates in humid tropical carbonate regions.

(d) At present rates, the most highly developed forms could have been produced within the last 200,000 years and because there is evidence to indicate that the karst may not have been glaciated for up to 250,000 years, such a period has been available for solutional development.

Because the Nahanni region has not been glaciated for an extremely long period, it may be one of only a few high-latitude carbonate terrains that have had time to develop fully. Its very existence questions the validity of the concept that the intensity and direction of karst development is climate-controlled. In the Nahanni at least, the structural and lithological properties of the host limestone appear to have been of greater importance. The labyrinth karst type present in regions of humid-tropical to sub-arctic climate, is an outstanding example of a structurally-controlled karst landscape. It may well be that the same controls also influence the distributions of other karst types.

abstract: Doctor of Philosophy (PhD)


title: Correlates of Mucosal Humoral Immunity in Peripheral Blood

subject:
Mucosal IgA
B cells
Peripheral Blood
Bystander activation
Mucosal Homing
Medical Immunology
Medical Immunology

abstract:
Several labs have previously demonstrated that humoral immune responses at one mucosal tissue can disseminate to other mucosal sites, giving rise to the theory of the common mucosal immune system (CMIS). Evidence that demonstrates a similar link between systemic immune responses and mucosal protection is lacking despite indications that both mucosal and systemic memory B cells share common circulatory pathways. The focus of this study is to determine the contribution of blood-borne B cells to mucosal immunity in humans, and how B cells trafficking through blood can be induced to traffic to mucosal tissues.

To address these aims, I have performed several analyses of active and inactive peripheral blood memory B cell (MBC) populations in normal, healthy humans. Analysis of recently activated blood B cells confirmed the revealed that the majority of pre-plasma cells (PPC) in blood of healthy, normal humans secrete IgA, and that the majority of IgA- positive PPC secrete primarily polymeric IgA. A large fraction of blood PPC also express CCR10, and this population contains the highest fraction of IgA-expressing and pIgA-secreting PPC in blood. In contrast, most CCR10- PPC secrete IgG, although a small fraction secretes and stains positive for IgA, and analysis of α4β7expression by blood MBC revealed that CCR10 is more inclusive of IgA-switched and pIgA-secreting PPC in blood. The data presented in this study demonstrate that IgA+/CCR10+ PPC represent the mucosal subset of PPC in the blood of healthy humans, and can be investigated as representative of recent or ongoing mucosal immune responses.

In vitro polyclonal stimulation of blood MBC through CD40 was able to induce CCR10 expression by blood MBC treated with IL-21, IL-2, IL-10 with additions of other germinal center (GC) cytokines such as IL-5 and TGF-β enhancing CCR10 induction. Surprisingly, CCR10 expression by IgG MBC stimulated under these conditions was similar to that of IgA MBC, demonstrating that CCR10 expression is not limited to IgA- switched B cell clones. The results of this study demonstrate that CCR10 expression is inducible by many GC factors, and importantly, is not limited to IgA-switched B cells.

Systemic immunization of healthy volunteers with tetanus toxoid/diphtheria vaccine induced a robust systemic IgG response, but also resulted in a post-immunization mobilization of IgA PPC in blood. These PPC were not specific for tetanus or diphtheria, and in several volunteers showed specificity for mucosal pathogens such as poliovirus (PV) and herpes simplex virus (HSV) glycoproteins. In addition, stimulation of anti-HSV IgG memory was also observed. Thus we have demonstrated that a systemic immune response is capable of inducing antibody relevant to mucosal immunity, possibly exposing a mechanism through which systemic and mucosal humoral immune responses are linked.

The studies presented here demonstrate the presence of mucosal B cell memory in blood and thus provide new insight into ways to assess and manipulate mucosal immunity.

abstract: Doctor of Philosophy (Medical Science)