title: Simulation of Intersubchannel Mixing in a Triangular Nuclear Fuel Bundle Geometry

contributor:
Lightstone, Marilyn
Tullis, Stephen
Mechanical Engineering

abstract: Predicting temperature distributions in fuel rod bundles is an important component of safety analysis of nuclear reactors. Intersubchannel mixing acts to homogenize coolant temperatures thus reducing the likelihood of localized regions of high fuel temperature. Previous research has shown that intersubchannel mixing in nuclear fuel rod bundles is enhanced by a large-scale quasi-periodic energetic fluid motion, which transports fluid on the cross-plane between the narrow gaps connecting subchannels. This phenomenon has also been observed in laminar flows. Unsteady laminar flow simulations were performed in a simplified bundle of three rods with a pipe. The objective was to study the dynamics of this flow phenomenon, the interactions between subchannels, and the impact on thermal mixing. Three similar geometries of varying gap width were examined. Thermal mixing was driven by the advection of energy between subchannels by the cross-plane flow. Flow through the rod-to-wall gaps in the wall subchannels alternated with a dominant frequency, particularly when rod-to-wall gaps were smaller than rod-to-rod gaps. Cross-plane flow through the rod-to-rod gaps in the triangular subchannel was irregular in each case. This was due to the fundamental irregularity of the triangular subchannel geometry. Vortices were continually broken up by cross-plane flow from other gaps due to the odd number of fluid pathways within the central subchannel. Significant phase-linking between rod-to-wall gaps was observed such that a peripheral circulation occurred through each gap simultaneously. Cross-plane flow in subchannel geometries is highly interconnected between gaps. The flow structure through the gaps is more complicated than has been previously reported and depends very much on the subchannel geometry.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Downscaling Satellite Microwave Observations to Facilitate High Resolution Hydrological Modelling

type: Animation Thesis Other

contributor:
Coulibaly, Paulin
Geography and Earth Sciences

subject:
Remote Sensing
Hydrology
Downscaling
Bias Correction

abstract:
Soil moisture is an essential climate variable and provides critical state information for hydrological applications. The state of soil moisture influences the exchange of water and energy between the earth surface and the atmosphere, partitions infiltration and runoff, can limit the net primary productivity of a region and govern the dynamics of geochemical processes. Satellite observations can be used to provide information about this important variable but are often available at a scale that is far greater than most hydrological processes. The scope of the research presented in this dissertation was to identify practical methods to facilitate the use of coarse scale satellite soil moisture information in higher resolution hydrological and land-surface modelling applications. Research was primarily conducted in the Hamilton-Halton watershed of Southern Ontario, Canada, although other watersheds and datasets were periodically used in some chapters.
	A comprehensive review was conducted on the use of high resolution soil moisture information for hydrological applications, and data assimilation was identified as the most common method for integrating soil moisture information into a hydrological model. It was also identified that most watersheds displayed the property of temporal persistence and that root-zone soil moisture was of greater importance than surface soil moisture (Appendix B). In light of this information, the focus of this research was the downscaling of soil moisture and brightness temperature (TB) observations from the Soil Moisture and Ocean Salinity (SMOS) passive microwave satellite.
Satellite observations are sensitive to surface soil moisture, while rootzone soil moisture provides the greatest benefit to hydrological and land surface applications. To overcome this discrepancy, artificial neural networks (ANN) were evaluated as a method to estimate rootzone soil moisture from surface observations that accounted for the known non-linearities of soil moisture processes. The ANN model was trained with a numerical soil moisture physics model and validated using in situ observations from the McMaster Mesonet and USDA SCAN sites. The ANN was capable of accurately depicting the rootzone soil moisture based on its training data at multiple sites, but was limited when the temporal distribution of soil moisture at a particular site was considerably different than the training data. Therefore, with the appropriate training data, ANNs are a viable method for predicting rootzone soil moisture from surface observations such as those available from satellites.
To provide high resolution soil moisture information from coarse resolution satellite data, bias correction was proposed and evaluated as a downscaling method for both soil moisture and TB. Using in situ data from two well instrumented USDA watersheds and a hydrological land-surface scheme (HLSS), it was found that temporal evolution of both soil moisture and TB at fine scale (~1 km) could be well characterized by the temporal evolution of the coarse scale (~20 km) soil moisture and TB. The fine scale spatial distribution of soil moisture could be predicted with a high degree of skill by correcting the bias between the coarse and fine scale soil moisture/TB.
In studying the correction of biases, it was found that naïve application of bias correction methods could result in the introduction of multiplicative biases in the bias corrected dataset. The theoretical implications of this for a data assimilation system were discussed although not yet evaluated. A bootstrap resampling approach was evaluated as a solution to this problem and it was found that resampled data could result in a robust bias correction that eliminated additive bias in most instances while limiting the induction of multiplicative bias. This new method was found to significantly outperform the standard bias correction techniques.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Soil moisture is an important hydrological variable. The state of soil moisture controls the partition between the runoff and infiltration as well as the exchange of heat from the surface to the atmosphere. Therefore, an accurate depiction of the state of soil moisture is important for producing accurate flood and drought forecasts, numerical weather prediction and agricultural forecasts. The state of soil moisture can be observed from space using microwave remote sensing measurements. However, the resolution of most passive microwave observations, such as those from the European Space Agency Soil Moisture and Ocean Salinity (SMOS) satellite are at a resolution of approximately 40 km which is far more coarse than the approximately 1 km resolution of most hydrological processes. The work in this thesis presented bias correction methods as a mean to match the spatial scale of the satellite observations to high resolution hydrological and land surface models. These data were generated and compared using an advanced land surface hydrological scheme under development at Environment Canada. It was found that simple bias correction methods were capable of effectively downscaling SMOS observations to the a scale of 1 km without the loss of information from the satellite. A new bias correction method was also presented that was found to significantly outperform standard techniques.


title: Uncovering evidence for the inhibition of return effect in the non-spatial domain

contributor:
Milliken, Bruce
Psychology

subject:
attention
Inhibition of Return
episodic integration
novelty
non-spatial
cognition
intervening event

abstract:
Our attentional system has the remarkable ability to allow familiar contexts to guide attentional orienting, while still retaining the ability to orient rapidly to novelty in our environment.  Many cognitive paradigms have been used to investigate the particular process that is responsible for orienting attention to novel events, but each paradigm has produced a unique set of boundary conditions.  One such paradigm has studied an effect labelled Inhibition of Return (IOR), which has been argued to tap into an attentional mechanism that rapidly orients attention to novelty, but only in the spatial domain.  The IOR effect was initially taken as evidence of a fundamental difference between spatial attentional orienting and non-spatial attentional orienting.  However, there were a small number of early studies that questioned the view that the IOR effect can only be observed in the spatial domain.
In this dissertation, I built upon the evidence for non-spatial IOR by uncovering the effect using a Target-Target (TT) procedure.  Although a number of prior studies had failed to observe non-spatial IOR using a TT procedure, I was able to uncover non-spatial IOR effects using a TT procedure by introducing an intervening event.  The IOR-like effect that was uncovered using this procedure was labelled the intervening event effect.  I introduced a dual process framework to explain the intervening event effect.  According to the dual process framework, intervening events between consecutive targets can disrupt an episodic integration process, allowing the influence of a separate opposing process to be measured more directly.  Using the dual process framework, I studied the level of processing of the intervening event that was necessary to disrupt episodic integration, as well as the context-sensitivity of the episodic integration process.  Lastly, I investigated the role of subjective expectancy in the studies used to measure non-spatial IOR in this thesis.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Design & Fabrication of a Microfluidic Device for Clinical Outcome Prediction of Severe Sepsis

contributor:
Selvaganapathy, P. Ravi
Biomedical Engineering

subject:
Microfluidic device
cell-free DNA
Severe sepsis

abstract:
Sepsis is an uncontrolled response to infection. Severe sepsis is associated with
organ dysfunction, and has mortality rate of 30-50%. Identification of severity of sepsis
and  prediction  on  mortality  is  crucial  in  making  clinical  decisions.  Recently,  cell-free
DNA (cfDNA) in blood was found to have high discriminative power in predicting ICU
mortality in patients with severe sepsis. In an analysis of 80 severely septic patients, the
mean  cfDNA  level  in  survivors  (1.16±0.13μg/ml)  was  similar  to  that  of  healthy
volunteers (0.93±0.76μg/ml), while that of non-survivors (4.65±0.48μg/ml) was notably
higher.  Therefore,  rapid  quantification  of  cfDNA  concentration  in  blood  will  enable
physicians to quickly predict mortality of sepsis and decide on treatment.
Current  methods  for  quantification  of  cfDNA  involve  multiple  steps  including
centrifugation,  DNA-extraction  from  plasma,  and  its  quantification  either  through
spectroscopic methods or quantitative PCR. The whole process is time consuming, thus is
not  suitable  for  immediate  bedside  assessment.  To  solve  the  problems,  a  microfluidic
device  is  designed  and  fabricated  in  this  thesis,  which  is  potential  for  cfDNA
quantification  directly  using  blood  in  5  minutes.  The  goal  is  to  use  this  device  for
distinguishing  survivors  or  healthy  donors  from  non-survivors  in  patients  with  severe
sepsis.   The  two-layer  device  consists  of  a  sample  channel  (top)  and  an  accumulation
channel (bottom) that intersect each other. The accumulation channel is preloaded with
1%  agarose  gel,  and  the  blood  containing  cfDNA  and  intercalating  fluorescent  dye  is
loaded  in  the  sample  channel.  Fluorescently  labeled  DNA  is  able  to  be  trapped  and
concentrated at the intersection using a DC electric field, and fluorescent intensity of the
accumulated  DNA  is  representative  of  its  concentration  in  the  blood.  The  simulated
electric field in the sample channel reveals that both the magnitude and the gradient of
electric field reach their maximum values at the intersection. Force analysis shows that
DNA was driven into the gel by the dominate electrophoretic force, while red blood cells
moved away from the gel due to a strong dielectrophoretic force.
In this thesis, 4 types of samples have been used to characterize the performance
of the device. It showed that DNA was efficiently accumulated at the intersection, and the
fluorescent  intensity  could  be  measured  using  a  fluorescent  microscope.  Samples  from
healthy donors  were  able to  be distinguished from  that of severely  septic  patients  in  5
minutes.  However,  better  resolution  was  needed  for  differentiating  various  cfDNA
concentrations in patient samples. The discussion on the effect of applied voltage showed
that  9V  is  an  optimized  setting  compared  with  3V  and  15V.  In  addition,  it  has  been
proved that the fluorescent reagent could be immobilized in the device and the sample
preparation could be absolutely eliminated. In  summary,  the  device  proposed  in  this  thesis  is  capable  of  distinguishing
severely septic patients  from healthy donors using  clinical plasma in 5  minutes, and is
potential  to  be  applied  in  clinical  blood  samples.  It  has  low  cost,  and  is  ready  to  be
developed into a fully functioned system. This tool can be a valuable addition to the ICU
to rapidly assess the severity of sepsis for informed decision making.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: An Investigation into the Use of an Optimal Grouping Procedure in Land Use Capability Analysis, Pichincha Province, Ecuador

contributor:
Wood, H.A.
Geography

subject:
methodology
development
soil
land
economic
crop yield
farm activities

abstract: The study concerns the development of a methodology which will allow the rating of soil or land units in view of their sustained economic capacity. Some literature is surveyed to show that no known scheme justifies statistically the number of classes used;many schemes avoid the use of empirical crop yield data altogether. The factor analysis of farm activities and crop yield data will provide a set of scores, incorporating the important variables only, which may be grouped by the statistical method ·which is the core of the work. The Andean portion of the Province of Pichihcha, Ecuador, was the area studied. A number of farm types were discovered, differentiated by levels of investment and subsequently by type of activity. The strong crop yield/environmental correlations needed to create an improved land use capability scheme were found not to exist, but some important observations were made upon the profitability of the crop holdings and the fertility status of the soils. A number of land types with regional tendencies were found.

abstract: Thesis

abstract: Master of Arts (MA)


title: Characterization of Oncolytic Bovine Herpesvirus Type 1

contributor: Medical Sciences (Molecular Virology and Immunology Program)

subject:
oncolytic virus
breast cancer

abstract: Oncolytic viruses (OV) are a promising alternative cancer therapy due to their specificity and lack of debilitating side effects, such as those which typically accompany conventional therapeutics such as chemotherapy and radiation. Bovine herpesvirus type 1 (BHV-1) is an alphaherpesvirus with the ability to infect and kill multiple human tumor cell types. In comparison to other species-specific viruses, for which deficiencies in type I interferon signalling pathways dictates cellular sensitivity to infection, mutations in KRAS were found to correlate with high levels of BHV-1 replication. Interestingly, BHV-1 is able to induce cellular cytotoxicity in the absence of a productive infection. In contrast to current breast cancer (BC) treatments, which are largely based on receptor expression status, BHV-1 is able to infect and kill BC cells and breast cancer initiating cells (BCICs) from luminal and basal subtypes. Furthermore, BHV-1-infected BC cells are significantly diminished in their capacity to form tumors in vivo, suggesting that BHV-1 reduces the tumor forming capacity of BCICs. Combination therapy involving OVs has been used to exploit differences in the mechanism of tumor cell death elicited by individual treatments. Treatment with epigenetic modifiers such as 5-Azacytidine (5-Aza), a DNA methyltransferase inhibitor, has been shown to increase the antitumor activity of OVs. Our data indicates that 5-Aza strongly synergises with BHV-1, increasing virus replication and cytotoxicity in vitro. In vivo, BHV-1 monotherapy did not significantly impact tumor growth or survival of CR bearing subcutaneous breast tumors; however, combination therapy with 5-Aza significantly decreased the number of secondary lesions compared to BHV-1 monotherapy. Overall, the data presented in this dissertation indicate that BHV-1 is a promising broad spectrum OV with a unique mechanism of tumor cell targeting, and the ability to infect and kill tumor cells independent of a productive infection.

abstract: Thesis

abstract: Doctor of Philosophy (Medical Science)


title: FOSTERING THE USE OF AN EVIDENCE-BASED APPROACH AND STANDARD

contributor:
MacDermid, Joy
Tang, Ada
Kho, Michelle
Health

subject:
Evidence-based Practice
Outcome Measures
cross-cultural adaptation

abstract:
Monitoring results is the final step that determines the impact of an evidencebased
practice (EBP) decision. A variety of health outcomes can be expected to change
following rehabilitation; therefore, outcome measures (OMs) are a major focus of EBP in
rehabilitation. For instance, in patients with hand injuries, physiotherapy (PT) services
focus on enabling patients to improve their functional use of the traumatized hand.
Examining current practice of physiotherapists (PTs) in Saudi Arabia with respect to use
of EBP and OMs can serve as a basis for understanding any identified gaps in knowledge
before the full effect of translation and adoption of new patient self-reported outcomes
(PROs) instruments can be seen in clinical practice. Therefore, this thesis was designed in
two phases, incorporating two papers, to address EBP and PROs and their adoption in the
evolving PT practice in Saudi. The first paper is a survey that aimed to determine the
current self-reported attitudes, skills, and knowledge of PTs in Saudi Arabia toward EBP
and outcome measures, including PROs. The second paper describes the process of crosscultural
Arabic translation and adaptation of the Patient-Rated Wrist and Hand Evaluation
(PRWHE) and reports estimates of the psychometrics properties of the translated
measure. Finally, the thesis addresses overall areas of limitations and includes
suggestions for future refinement and research in order to foster and facilitate EBP
implementation in the cultural context of the evolving physiotherapy profession in the
health systems of Saudi Arabia.

abstract: Thesis

abstract: Master of Science Rehabilitation Science (MSc)


title: Factors Affecting Surface Topography in Diamond Turning

contributor:
Veldhuis, Stephen C.
Mechanical Engineering

subject:
Ultraprecision Machining
Imbalance
Rotordynamics
Diamond Turning

abstract: Ultraprecision, single point diamond turning (SPDT) is a tool based machining technology that allows the ability to produce high quality surface finishes on the order of nanometers while meeting tight form tolerances on the order of micrometers. It is generally agreed that surface finish in SPDT is primarily affected by four factors: Tool edge quality, relative vibration between the tool and workpiece, material properties and microstructure, and tool geometry (nose radius and machining parameters) machining. To the author’s knowledge, no work has been done to combine all the factors to study their effect on surface generation in SPDT.  This is important given that the factors are highly interdependent. Two diamond tools with nose radius of 12mm were used; however, one of them was chemically honed. Results suggest that the honed tool provides a much better surface finish with a significantly reduced amount of running-in stage tool wear. The cutting edge radius of the diamond tools was measured using a novel 3D confocal laser microscope to analyze the chemical honing process and to measure tool wear. The presence of built-up edge (BUE) is more prominent on the honed tool earlier in its life which results in unpredictable surface roughness to appear sooner than on the regular tool. To understand the dynamics of the machine, a redesign of the tool holder bracket was done to increase stiffness. Modal tests were then performed on it to verify performance improvement. With an understanding of the vibration and its effect on the cutting force, a 400Hz disturbance frequency was detected in the cutting forces. From a 3D scan of the surface, a total of 24 undulations on the surface of the part were observed when the spindle speed was set to 1000RPM The machine was instrumented and a rotordynamic investigation was carried out to determine the cause and nature of the vibration in an effort to reduce it and in so doing improve surface form accuracy.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Linear Precoding in Wireless Networks with Channel State Information Feedback

contributor:
Timothy, Davidson
Electrical and Computer Engineering

subject:
Wireless Networks
Interference Alignment
Degrees of Freedom
Downlink
Incremental Feedback
Grassmannian
Spatial Reuse Precoding
Fractional

abstract:
This thesis focuses on the design of linear precoding schemes for downlink multiple-input
multiple-output (MIMO) networks. These schemes are designed to be amenable to implementation in wireless networks that allow rate-limited feedback of channel state information (CSI). In the first half of this thesis, memoryless quantization codebooks are designed and incremental vector quantization techniques are developed for the  representation of CSI in MIMO point-to-point links and isolated (single-cell) downlink networks. The second half of the thesis seeks to design linear precoding schemes for the multi-cell downlink networks that can achieve improved performance without requiring significantly more communication resources for CSI feedback than those required in the case of an isolated single-cell. For the quantization problem, smooth optimization algorithms are developed for the design of codebooks that possess attractive features that facilitate their implementation in practice in the addition to having good quantization properties. As
one example, the proposed approach is used to design rank-2 codebooks that have
a nested structure and elements from a phase-shift keying (PSK) alphabet. The designed
codebooks have larger minimum distances than some existing codebooks, and provide tangible performance gains.
To take advantage of temporal correlation that may exist in the wireless channel, an incremental approach to the Grassmannian quantization problem is proposed. This approach leverages existing codebooks for memoryless quantization schemes and employs a quantized form of geodesic interpolation. Two schemes that implement the principles of the proposed approach are presented. A distinguishing feature of the proposed approach is that the direction of the geodesic interpolation is specified implicitly using a point in a conventional codebook. As a result, the approach has an inherent ability to recover autonomously from errors in the feedback path. In addition to the development of the Grassmannian quantization techniques and codebooks, this thesis studies linear precoder design for the downlink MIMO networks in the cases of small networks of arbitrary topology and unbounded networks that have typical architectures. In particular, a linear precoding scheme for the isolated 2-cell network that achieves the optimal spatial degrees of freedom of the network is
proposed. The implementation of a limited feedback model for the proposed linear precoding scheme is developed as well. Based on insight from that model, other linear precoding schemes that can be implemented in larger networks, but with finite size, are developed. For unbounded networks of typical architecture, such as the hexagonal arrangement of cells, linear precoding schemes that exploit the partial connectivity of the network are presented under a class of precoding schemes that is referred to as spatial reuse precoding. These precoding schemes provide substantial gains in the achievable rates of users in the network, and require only local feedback.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Albert Camus' Critique of Modernity

contributor:
Planinc, Zdravko
Religious Studies

subject:
Camus
modern
post-modern
Greek anthropology
political philosophy

abstract:
The aim of my study of Camus is twofold. The first aspect concerns the content of his books, the second their formal structure or organization. In contrast to much current scholarship, which interprets Camus' primary concerns as modern and even post-modern, I argue that his ambition runs in the opposite direction historically: Camus' principal aim is to articulate a Greek anthropology and political philosophy. This positive ambition has a critical component as well. Camus's Hellenism is formulated in part through a critical engagement with modernity and an exploration of its Christian origins.

The second aim of my study is to explore the structure of Camus' corpus. The fact that Camus organized his books into several different stages or "cycles" is well known and often discussed by commentators in the context of other interpretive matters. However, it is rarely examined in its own right and almost never interpreted in detail. The most common way that it is understood is as straight autobiography. In this view the absurd, rebellion, and love - the guiding themes of the three principal cycles of Camus' books - are understood as stages in his personal philosophical development. The account contradicts Camus' own explicit statements about the allegedly autobiographical character of his work and skirts the fundamental question of interpretation by assuming that it has already been answered. Contrary to this account I argue that the organization of Camus' books is an intentional literary device that contributes significantly to our understanding of the content of his work.

My study amounts to new interpretation of Camus that hopefully will open up new and fruitful avenues of research regarding his accomplishments as a philosopher and writer.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Ga-Assisted Nanowire Growth on Nano-Patterned Silicon

contributor:
LaPierre, Ray
Engineering Physics

subject:
nanostructure
semiconductor
molecular beam epitaxy
nanowires

abstract:
GaAs nanowires (NW) have been grown on Si (111) substrates by the self-assisted vapor-liquid-solid (VLS) mechanism using molecular beam epitaxy (MBE). Substrates were prepared with nano-patterned oxide templates using electron beam lithography (EBL) in order to achieve position controlled NW growth.
Early experiments uncovered several key issues with regards to the patterning process. Cross-sectional lamella prepared using the focused-ion beam (FIB) technique were used to study the NW-substrate interface using transmission electron microscopy (TEM). Undesirable growth outcomes were found to be caused in part by an unintended residual layer of oxide. Uniform NW dimensions were then obtained by improving the pattern transfer method. The effects of deposition parameters on the growth results were then explored in further experiments.
The first systematic study of the axial and radial growth rates of vertical NWs in the positioned array was conducted. It was proposed that the observed expansion of the Ga droplet in Ga-rich growth conditions results in a slight inverse tapered morphology, promoting significant radial growth. While the growth rates were shown to be approximately constant in time, their measured values were found to increase with increasing pattern pitch and decrease with increasing hole diameter.
 A phenomenological model was then developed based on the principle of mass conservation. A fit to the experimental data was obtained by calculating the collection of growth material supplied by a secondary flux of both gallium and arsenic species desorbing from the oxide surface between the NWs, subsequently impinging on the liquid droplet and NW sidewalls. The reduction of this contribution due to shading of the incident and scattered flux by neighboring NWs in the array was able to account for the differences in final NW morphologies observed with increasing pattern pitch. This model demonstrates the significant impact of secondary adsorption in patterned self-assisted NW growth.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: Palynology of the Lower Colorado Group (Late Lower Cretaceous)and its Lithological Equivalents in Central and West-Central Alberta, Canada

contributor:
Radforth, N.W.
Biology

subject: 161 miospore, 122 microplankton, species, central, west-central Alberta,

abstract:
161 miospore species and 122 microplankton species are described from 106 samples in six sections of the Lower Colorado Group and its equivalents in central and west-central Alberta. Two miospore species, and two genera and twenty-five species of microplankton, are newly described.
The miospore and microplankton assemblages are used as a basis for division of the Lower Colorado Group into several time-stratigraphic units. The age of the Group is determined as Upper Albian (latest Lower Cretaceous).
A method for defining recurrent microplankton species groups is developed and applied to assemblages from two of the sections. The distribution of the recurrent groups formulated is shown to be correlated in part with palynological, lithological and other data.
Application and extension of the results and conclusions of this investigation should prove useful in understanding many aspects of western Canadian Cretaceous stratigraphy and in the investigation of microplankton occurrence patterns from other deposits.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Advanced Numerical Modeling of Fiber-Reinforced Elastomeric Isolators (FREIs)

contributor:
Tait, Michael
Konstantinidis, Dimitrios
Civil Engineering

abstract:
Fiber-reinforced elastomeric isolators (FREIs) are relatively new type of elastomeric bearing that utilize fiber-reinforced polymer (FRP) material for the reinforcing material. FREIs have lower weight and potentially easier manufacturing process compared with conventional seismic isolators. The viability of FREIs has been investigated through a number of experimental tests studies. However, numerical modeling of FREIs is required to better understand their vertical and lateral response characteristics, and to investigate the response of isolated structures using FREIs.
In this research, 3D finite element analysis (FEA) is carried out to investigate the vertical response of FREIs with various numbers of elastomer layers and reinforcing materials. In addition, the lateral response of FREIs is studied using 3D FEA. Experimental test results from three previously tested isolators were used to evaluate FEA models and subsequently, a series of FEA were carried out to investigate the sensitivity of the lateral response of FREIs to the direction of loading.
A new computational model is proposed to enhance the time history analysis of structures seismically isolated with FREIs. The proposed Pivot-Elastic model is capable of predicting the complex lateral response of FREIs. In order to evaluate the predictions of the proposed model, nonlinear time history analyses of a two-storey steel moment frame structure seismically isolated with FREIs were carried out, and the predicted response of the structure was compared against the results from a previous shake table study.
The lateral response of rectangular FREIs, a shape suitable for shear wall structures is investigated through experimental testing and 3D FEA. A series of time history analyses, using ten earthquake ground motions are carried out on a two-storey reinforced concrete shear wall structure seismically isolated using rectangular shape FREIs. The efficiency of the isolation system composed of rectangular FREIs was evaluated by investigating the seismic response of the structure with and without the seismic isolation system.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: An Examination of Pre and Postnatal Women's Leisure-Time Physical Activity Behaviour and Beliefs: A Social Cognitive Perspective

contributor:
Bray, Steven
Kinesiology

subject: Health, research, leisure-time, physical activity, women, social-cognitive

abstract:
Health research has demonstrated that regular leisure-time physical activity
(LTPA) during pregnancy and the postnatal period may play a crucial role in managing the physical and psychological challenges that women face during these times of transition. The purpose of this dissertation was to investigate LTPA patterns during pregnancy and in the postnatal period and identify social-cognitive correlates associated with regular LTPA. Three inter-related studies were conducted.
The purpose of Study 1 was to conduct an in depth month-to-month investigation of LTPA from 3 months prior to conception to 7 months following childbirth. An assessment of 309 pre and postnatal women revealed that LTPA started to decline in the first trimester of pregnancy, continued to decline at a steady rate until childbirth and then
increased during the postnatal period. In addition to illustrating the average growth curve, the results from the multi-level moding analyses indicated substantial individual variability around the average growth curve. Future research should identify social cognitive factors that are associated with LTPA during this time of transition.
Accordingly, Study 2 investigated psychosocial correlates of LTPA during
pregnancy. The study engaged pregnant women in the listing of salient barriers to LTPA at 4 different time points during pregnancy (e.g., pregnancy weeks 18, 24, 30 and 36) and examined if barrier self-efficacy as well as a general measure of exercise self-efficacy were associated with LTPA during pregnancy. A total of 1168 barriers were content analyzed, yielding nine major themes. Hierarchical regression analyses supported both
forms of self-efficacy as predictors of LTPA. While Study 2 examined LTPA during pregnancy, Study 3 focused on the postnatal period. The first objective was to identify postnatal women's perceived LTPA barriers and outcome expectations. In general, the barriers reported were consistent with
barriers experienced by both asymptomatic and symptomatic populations as well as previous research examining barriers to exercise among postnatal women. The results of the open-ended outcome expectation elicitation generated a large number of physical, psychological and social outcome expectations. Approximately 90% of all outcome expectations listed under each category were classified into four groups. The second objective of Study 3 was to examine if outcome expectation likelihood, exercise self-efficacy
and barrier self-efficacy were associated with LTPA. In support of our
hypothesis, and consistent with social cognitive theory, self-efficacy was significantly associated with LTPA.
For many women engaging in regular LTPA during pregnancy and following the birth of a child is a challenge. The average growth curve results from Study 1 are promising; however the random effects analyses was significant indicating substantial individual variability about the average growth curve. Study 2 and Study 3 identified a number of salient barriers to LTPA which may hinder the initiation and maintenance of regular LTPA. Study 3 also identified salient outcome expectations that may severe a
motivational factors to engage in LTPA. The results suggest that self-efficacy represents an important social cognition is linked to higher levels of LTPA in the postnatal period. In conclusion, barrier and exercise self-efficacy may be important targets for intervention efforts to promote LTPA during pregnancy.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Environmental Influence on the Physiological Consequences of Feeding in Rainbow Trout, ONCORHYNCHUS MYKISS

contributor:
Wood, Chris M.
Biology

subject: ionic, osmotic, homeostasis, fasting animals, environment, seawater, dry trout, digestion,

abstract:
Ionic and osmotic homeostasis, and the intricately linked mechanisms of acid-base balance are critical for the survival of fish. To date, the role of the gastrointestinal (GI) tract in these processes has received only limited study, and our knowledge has been gained almost exclusively through studies conducted in fasting animals. The impacts of feeding and digestion, ubiquitous processes in the natural environment, are likely to be
significant but have been overlooked. The current thesis addressed these shortfalls in our current understanding. Research focused on the rainbow trout (Oncorhynchus mykiss), a euryhaline species capable of withstanding the opposing challenges of life in seawater (diffusive influx of ions and loss of water) and freshwater (diffusive loss of ions and gain of water), and concentrated on its physiological response to ingestion of a meal of
commercial, dry trout food, containing concentrated salts and little water. The net absorption and secretion of ions and water was tracked in each section of the GI tract of the rainbow trout over a detailed time course using an experimental diet that contained a simple inert marker, in the presence of external freshwater or seawater. Additionally, changes in overall blood chemistry were investigated to examine changes in osmotic,
ionic and acid-base regulation during digestion.
Feeding in freshwater resulted in the loss of endogenous water to the GI tract
during digestion. Additionally, the meal provided much needed ions to balance those lost by diffusion; indeed all of the ingested ions were assimilated along the GI tract except for sodium which was absorbed in the stomach, but secreted in the intestine such that overall sodium balance was close to zero. Feeding also created a metabolic base load (an increase in the concentration of base, or HC03- due HCl secretion into the stomach
lumen) that alkalinized the blood (i.e. caused a rise in pH), a phenomenon known as an alkaline tide. The base load was subsequently removed from the blood through increasedexcretion of base to the water via the gills.
In seawater, the commercial diet again provided an avenue for water loss. This was potentially deleterious to an organism already suffering from diffusive water loss to the environment. Ion absorption from the diet was negligible, except for potassium and calcium, which were readily assimilated. As in freshwater, digestion resulted in an alkaline tide, however the mechanism of acid-base homeostasis differed with the excess
base likely being excreted into the intestine. In contrast to freshwater fish, the gills took up additional base from the external environment, prolonging the acid-base disturbance in seawater fish.
Overall, feeding was a dynamic process with far reaching systemic physiological effects. The research described highlighted intimate interactions between the processes of feeding and digestion and ion, water and acid-base homeostasis, and elucidated mechanisms that enable fish to inhabit a wide range of environments.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Liberal Unionist Party, 1886-1912

contributor:
Heathorn, S.
History

subject:
British political history
Liberal Unionist party
independence
conervative
alliance
government

abstract:
This dissertation consists of an examination of the Liberal Unionist party over the
entire period of its existence, from 1886to1912, and demonstrates the importance of the party to a complete understanding of British political history in the late-Victorian and Edwardian periods. The Liberal Unionist party retained a significant degree of
independence from other parties for far longer than historians have generally assumed. In particular, the relationship between the Liberal Unionist party and the Conservative party, with whom they co-operated in an electoral alliance from 1886 and participated in a coalition government from 1895 to 1905, continued to be fraught with tension and conflicts over parliamentary representation and ideology until the last years of the party's existence. Conversely, many Liberal Unionists retained ties of sentiment and ideology with the Liberal parties for many years after the Home Rule division of 1886. In the course of demonstrating the continued independence of the Liberal Unionist party, this dissertation examines the central and local party organization, the operation of the electoral alliance between the Liberal Unionists and Conservatives, and the construction and nature of Liberal Unionist identity. An important component of this dissertation is the identification of every Liberal Unionist candidate and M.P. based on a variety of primary sources (see Appendixes C and D), which allows for a more detailed and accurate discussion of the history of the party than previously had been possible.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Assessing the Long-Term Health Effects of Childhood Exposure to Adverse Air Quality: Case Study from Hamilton, Ontario (1975 - 2005)

contributor:
Elliott, Susan J.
Geography

subject: childhood exposure, air pollution, long-term health, Hamilton, Ontario, levels, socio-demographic,

abstract:
This thesis examines the relationship between childhood exposure to air pollution and long-term health. The research is based on an earlier study (1978-1986) that examined the relationship between exposure to air quality and respiratory health for a cohort of elementary school-aged children (n=3,202). These children resided in four distinct neighbourhoods in Hamilton, Ontario, which exhibited significant gradients in air pollution levels.
Informed by the Life Course Health Development model, a survey was developed and administered on a reconstructed cohort (n = 395). The following objectives were addressed: 1) to determine the current health status of the reconstructed cohort; 2) to assess the potential relationship between childhood exposure to air pollution and adult respiratory health; and, 3) to explore factors mediating this relationship. Data was collected for a range of variables including residential and occupational histories, socio-demographic variables, and health outcomes. The dataset was merged with data from childhood on respiratory health, exposure to air pollution, and socio-demographic variables.
Results indicate that a relatively high percentage of respondents had asthma in childhood (11%) compared to the original cohort (5.5%). In addition, prevalence rates of most health outcomes were higher than those of the Canadian population. Despite the gradient in air pollution levels, there were no significant differences in health status across neighborhoods. However, results of bi-variate and multi-variate analysis indicate possible significant associations between childhood exposure to S02 and hospital visits for asthma, asthma incidence in adulthood, and ever being diagnosed with asthma for females. For males, results suggest that childhood exposure to S02 is not linked to respiratory health. Factors related to the macro and micro environments also play significant roles in long-term health.
This thesis made significant contributions to knowledge by suggesting that childhood exposure to S02 may impact long-term respiratory health for females, and may be linked to inflammatory diseases.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Thermodynamic Optimization Under Topological Constraints

contributor:
Malakhov, Dmitri V.
Materials Science and Engineering

subject: Computational thermodynamics, materials, temperatures, liquid, solid,

abstract:
Computational thermodynamics is a powerful tool for solving practically important problems including the design of new materials and the analysis of their internal and external stability. This thesis contributes to computational thermodynamics by proposing several practical solutions to eliminate the so-called thermodynamic artifacts rather frequently found in thermodynamic assessments.
First, a method is developed to eliminate the artifacts such as inverted miscibility gaps in the liquid phase at high-temperatures and reappearance of the liquid phase at low-temperatures or reappearance of a solid phase at elevated temperatures. This method is based on introducing a sufficiently dense mesh of knots (not related to experimental points utilized in the optimization) and ensuring that specific inequality conditions (topological constraints) governing the appearance of the phase diagram are satisfied in these knots. A feasibility of the approach proposed is exemplified by carrying out a re-optimization of the Mg-Sb system.
Generally re-optimization of a system would take months to get the optimized results. Hence, to minimize time needed to get rid of artifacts, two different quick correction methods are developed to eliminate the unrealistic inverted miscibility gap in the liquid phase at elevated temperatures. Both methods employ optimization under topological constraints via controlling the sign of the second derivative of the Gibbs energy. Their applicability is exemplified on the Sn-Zr system.
Also, a theoretical study was done on undulate phase boundaries. Usually, an inflection point on a phase boundary is considered as an unambiguous indication that one of the phases participating in the equilibrium is internally unstable, i.e., that it is prone to phase separation. It has been generally assumed that an inflection point may occur only if the thermodynamic model of this phase contains an excess Gibbs energy term. It is shown that in contrast to this assumption, inflection points on a phase boundary may appear when a pure solid component or a stoichiometric binary phase is in equilibrium with the ideal binary solution, which is internally stable.
Finally, in addition to the theoretical analysis on undulate phase boundaries, a thermodynamic optimization is done on an imaginary A-B binary system subjected to topological constraints. Since, Thermo-Calc does not have the necessary tools to implement such topological constraints as d^2T/dx^2 >0 or d^2T/dx^2 <0. A Fortran 90 program was developed to make use of these constraints.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Instant independence: Planning for crown wards

contributor:
Gladstone, James
Social Work

subject: Crown Ward, planning, independence, child welfare, CAS

abstract: The purpose of this research is to explore through a critical lens the ways in which independence planning for crown wards is reflected in recording documents and the extent to which such documentation suggests the nature of continued involvement with the youth in such planning processes. Data were gathered by examining planning documents used by Child Welfare agencies in Ontario for crown wards. To accommodate the evolving emergence of themes and conceptual patterns revealed in the data, a grounded theory approach and constant comparative method was used as detailed by Charmaz (2006). Independence planning involved crown wards in developing visitation plans with members of the family of origin, and included goal setting pertaining to the development of social skills and acquisition of educational qualifications and instrumental skills. The planning documents lacked specific behavioural examples, contextual understanding, specific examples of the efforts undertaken by CAS workers and caregivers to support goals, and examples of discussions between workers and crown wards. Planning documents generally reflected little involvement of the crown ward. Planning and OnLAC documents require modification so as to allow for and encourage qualitative information and greater input from the crown ward. Such modifications ought to be understood by Child Welfare management in terms of making planning processes more useful and beneficial to crown wards and CAS workers.

abstract: Thesis

abstract: Master of Social Work (MSW)


title: The Classical Spring Poem

contributor:
Murgatroyd, Paul
Classics

subject:
Clssical Spring poems
Greek
genre evolution
Latin

abstract:
Despite the existence of valuable commentaries on some Classical spring poems, this area of study has been insufficiently explored. After providing a definition and a schema of the spring poem as such, this dissertation investigates, through the detailed analysis of the specific spring poems (Catullus 46; Horace Odes 1. 4, 4. 7, 4. 12; Palatine Anthology 9. 363, 10. l, 2, 4, 5, 6, 14, 15, 16 and Ovid Tristia 3.12), the evolution undergone by this genre from the third century B.C. to the sixth century AD.

 The Greek spring poems form an obvious group, as their authors follow A.P. 10.1 as a model, employing its schema and some of its elements, while trying to vary and improve on the chronologically earlier poems. Distancing themselves from the Greek tradition, the Latin authors take the genre off in significant new directions, starting new trends and making major changes both in the content and tone of their poems. Defined by their thematic and generic admixture, the Latin spring poems are distinguished by a complexity, depth of thought and variety of form unkown to the Greek tradition.

From the spring poems of the Palatine Anthology to Ovid's Tr. 3.12, the genre has known a remarkable evolution. Despite the apparent simplicity of the theme, the authors of the Classical spring poems have reached high levels of sophistication in the way they have succeeded in transforming a relatively straight forward poetic form into a complex and sophisticated genre. Since this series of poems is more than a simple literary parlour game, but constitutes a genre on its own that illustrates, through its major features - stylistic refinement, the use of the Hellenistic techniques of imitatio cum variatione and aemulatio (especially in the Greek tradition, but also in the Latin spring poems) and the blending of literacy and mythological allusions (especially in Horace's spring poems) - typical aspects of Classical poetry, the analysis undertaken in this dissertation gives the Greek and Latin spring poems the critical attention they fully deserve.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Sacred Suspicion: Religion and the Origins of the Cold War, 1880-1948

contributor:
Streeter, Stephen
History

subject: Religion, Cold War, Franklin D. Roosevelt

abstract: This dissertation explores the role of religion in the origins of the Cold War from 1880 to 1948.  Building on David Foglesong’s research into the role of religion in shaping American missionaries, businesspeople, and public intellectuals’ perceptions of Russia, as well as Andrew Preston’s insights into the Franklin D. Roosevelt administration’s use of religious tropes to justify intervention against Nazi Germany from 1939 to 1945, this project focuses on the White House and US State Department’s efforts to manage diplomatic tensions and public controversies surrounding religious repression in Russia during the origins of the Cold War from 1880 to 1948. The central finding of this project is that during the period from 1933 to 1945, President Franklin D. Roosevelt and his personal allies such as Joseph Davies sought to minimize popular and official criticisms of Soviet religious policies as a part of Roosevelt’s program of pragmatic cooperation with the USSR. Eventually, anti-communist officials in the State Department managed to undermine Roosevelt’s public relations program in order to justify a more confrontational approach to the Soviet regime. Roosevelt’s poor health, growing personal isolation, and neglect of personal relationships with American Catholic leaders after 1943, as well as his failure to create a bureaucracy committed to his vision of post-war cooperation, meant that after his death religion could be used by anti-communists in their campaign to denigrate the Soviet Union. To gain popular support for its containment and roll-back strategies, the Truman administration called for a worldwide Christian crusade to eradicate atheistic communism. By shedding light on how well the Roosevelt administration was able to overcome US-Russian religious tensions, this project supports the “missed opportunities” thesis that the Cold War was not inevitable.  It also stands as an example of a growing body of scholarly research linking religion, diplomacy, and US foreign relations.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Combining CAR-T cells and Oncolytic Viruses for Cancer Immunotherapy

contributor:
Bramson, Jonathan
Health Sciences

subject: immunology oncology

abstract:
INTRODUCTION: Immunotherapy continues to garner strong support for use in the treatment of cancer. Adoptive transfer therapies offer a promising approach to combating metastatic disease. In addition, viruses can also be exploited to drive antitumor immunity and tumor destruction. While the use of chimeric antigen receptor (CAR)-engineered T cells has shown dramatic clinical benefit for use in blood-based cancers, solid tumors remain a significant hurdle.
METHODS: We have investigated the use of multi-faceted immunotherapies combining CAR-T cells with oncolytic virotherapy. We have also evaluated how these therapies interact with pre-conditioning lymphodepletion regimes.
RESULTS: In chapter 3, we investigated the differences between three similar chimeric receptors targeting NKG2DL. Upon adoptive transfer, we observed dramatic T cell-induced toxicity. In addition, there were stark differences in the severity of toxicity induced between different receptors or across different mouse strains, or if combined with pre-conditioning chemotherapy.
In chapter 4, we tested the ability of oncolytic vaccines to boost engineered T cells through their natural antigen receptor. While CAR-T cells could be boosted via oncolytic vaccines, prolonged T cell engraftment and successful oncolytic vaccine boost required pre-conditioning chemotherapy.
Further analysis revealed a lack of antitumor function of the CAR-T cells in vivo. iii
In chapter 5, we evaluated loading CAR-T cells with oncolytic viruses (OVs). Loading of CAR-T cells with OV did not impair CAR expression or functionality of the T cells. In addition, CAR target recognition did not impact the ability of OV-loaded cells to deposit OVs onto tumor targets. CAR-T cells loaded with OV also displayed enhanced antitumor functions as compared to either treatment alone.
CONCLUSIONS: The research described in this thesis reveals important information into the interactions between CAR-T cells and OVs, and how pre- conditioning regimes may influence responses from either or both therapies. Overall, our research offers novel insight into future CAR-T cell therapeutic developments.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Effects of Flange Holes on Flexural Behavior of Steel Beams

contributor:
Sivakumaran, K. S.
Tait, M.
Civil Engineering

subject:
steel
steel beams
flange hole
metal strength

abstract: When fastener holes are made in structural beams, the Canadian Steel Design Code CAN/CSA-S16.01 -Clause 14.1 (CSA, 2003) states that no deduction in flexural strength is needed for holes up to 15% of the gross flange area. This clause was established many years ago, however, over the years the mechanical characteristics of structural steel have changed. This research study focused on the effects of flange holes on the flexural behavior of steel I-beams made of ASTM A992 steel. This study was conducted primarily based on an experimental investigation involving 25 beam specimens. Holes of various diameters, ranging from 0% to 48% of the gross flange area were laid by drilling holes (a) in the midspan of the tension flange and (b) in the midspan of both the tension and compression flanges. Additionally, beams having holes with fasteners (snug tight) were performed. Based on the test results, this study recommended a design approach, which is analogous to an axial tension member provision as per the current CAN/CSA-S16.01 (CSA, 2003) standard. Accordingly, the effects of holes on the flexural strength can be ignored if the gross-section plastic moment is greater than a modified net-section fracture moment hence, beam members shall be designed to carry the gross-section plastic moment. Otherwise, the beam members shall be designed to carry the modified net-section fracture moment. The comparison of the recommended procedure with the 15% exemption rule as per current steel standard S16.01 (CSA, 2003) demonstrated that the current code provision is unnecessarily conservative for steel grades such as A992 steel. On the other hand, the current provision may be more conservative for high strength steels such as HSLA 80 steel, ASTM A913 Grade 60 and HPS-485W having a minimum yield-to-ultimate strength ration value of more than 0.85. The analytical portion of the research study involved the application of nonlinear finite element method to verify and comprehend the experimental results. The analytical study was conducted using ADINA FE program. The test beams were modeled using 4-node shell element that includes both geometric and material nonlinearities. The material model utilized in the FE analysis was developed based on the experimental-numerical simulation of standard tensile coupons.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Statistical Analysis of Longitudinal Data with a Case Study

contributor:
Narayanaswamy, Balakrishnan
Mathematics and Statistics

subject:
preterm birth
longitudinal data
imputation
statistical analysis

abstract: Preterm birth is the leading cause of neonatal mortality and long-term morbidity. Neonatologists can adjust nutrition to preterm neonates to control their weight gain so that the possibility of long-term morbidity can be minimized. This optimization of growth trajectories of preterm infants can be achieved by studying a cohort of selected healthy preterm infants with weights observed during day 1 to day 21. However, missing values in such a data poses a big challenge in this case. In fact, missing data is a common problem faced by most applied researchers. Most statistical softwares deal with missing data by simply deleting subjects with missing items. Analyses carried out on such incomplete data result in biased estimates of the parameters of interest and consequently lead to misleading or invalid inference. Even though many statistical methods may provide robust analysis, it will be better to handle missing data by imputing them with plausible values and then carry out a suitable analysis on the full data. In this thesis, several imputation methods are first introduced and discussed. Once the data get completed by the use of any of these methods, the growth trajectories for this cohort of preterm infants can be presented in the form of percentile growth curves. These growth trajectories can now serve as references for the population of preterm babies. To find out the explicit growth rate, we are interested in establishing predictive models for weights at days 7, 14 and 21. I have used both univariate and multivariate linear models on the completed data. The resulting predictive models can then be used to calculate the target weight at days 7, 14 and 21 for any other infant given the information at birth. Then, neonatologists can adjust the amount of nutrition given in order to preterm infants to control their growth so that they will not grow too fast or too slow, thus avoiding later-life complications.

abstract: Thesis

abstract: Master of Science (MSc)


title: A New Approach to the Experimental Study of Shyness: Person by Context Influences on Computer-mediated Social Communication

contributor:
Schmidt, Louis A.
Psychology

subject: Internet, computer-mediated technologies, social psychology, communication, behaviour, self-esteem

abstract:
In a series of five studies, I used the Internet and computed-mediated technologies as tools to revisit the longstanding issue within the fields of personality and experimental social psychology: "person by context" interaction on social communicative behaviour. The effects of the personality trait of shyness were examined in visually anonymous and non-anonymous conditions to see if the interaction of the person and context influenced social communication. Participants were paired in dyads and instructed to converse using a text-based online Instant Messenger program. Dyads were randomly assigned to converse with webcams or without webcams. For some types of behaviour (e.g., self-disclosure), shyness and level of visual anonymity interacted (Studies 1 and 2). Shy individuals disclosed more personal information in a visually anonymous context than a visually non-anonymous context. For non-shy individuals, self-disclosure was not influenced by the context. For other types of behaviour (e.g., affective language), the effect of shyness was consistent across context. To determine the specificity of the shyness-anonymity interaction, other person-anonymity interactions were examined (e.g., self-esteem, loneliness, sex of the participants) (Studies 3 and 4). Finally, the influence of the shyness-anonymity interaction on social communicative behaviour was examined in a cooperative performance-related task (Study 5).
These series of studies suggest that anonymity is a particularly salient contextual cue for shy individuals. Furthermore, the moderating effects of anonymity on shyness do not generalize to other characteristic of the person. Instead, anonymity moderates the other characteristics (e.g., self-esteem) uniquely. The present findings have theoretical implications to the study of person by context interactions by identifying how such interactions influence specific aspects of social communication. These findings also have practical or clinical implications. For example, the treatment of social difficulties related to high shyness, low self-esteem, or high loneliness, may involve specific treatment plans building off of modifications in anonymity. Shy individuals benefit from using the Internet as a social medium in which
they can control the level of anonymity as is demonstrated by their bolder behaviour during visually-anonymous conversations. The present findings also suggest that the Internet and computer-mediated technologies can be used in novel ways to study longstanding questions in personality and experimental social psychology.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Time River Blue Mouths Infinite Absence: Madness, Grief, Art

contributor:
Brophy, Sarah
English and Cultural Studies

subject:
Madness
Grief
Art
Yayoi Kusama
Bobby Baker
Merri Lisa Johnson
Anna Quon
Workman Arts
Queer
Buddhism
Death

abstract: My partner Zoë was killed in October 2013. We worked together as arts educators, mostly with people involved in the Canadian mental healthcare system. This thesis explores social conceptions of madness, drawing on theorists such as Tobin Siebers, Sara Ahmed, Lynne Huffer and Ann Cvetkovich, and engaging with works of art by people who have been involved in mental healthcare in some way. There is a simultaneous exploration of my process of grieving Zoë's death, drawing on the tradition of autocritique by writers such as bell hooks, Eve Kosofsky Sedgwick, and others. Chapter one looks at poetry produced by the Workman Arts Group and a zine by Anna Quon, investigating the impact of diagnoses of mental illness on the reception of art and artists, as well as the history of silencing and confinement of mad bodies. Chapter two explores the memoirs of Bobby Baker and Merri Lisa Johnson, emphasizing the impact of diagnosis on those not already marginalized by society, and drawing attention to the kinds of communities that memoirs produce, as well as the connection between community, capitalism, and the grievability of life. Chapter three looks at the paintings, performance art and installations of Yayoi Kusama to complicate the connection between madness and celebrity power, as well as Kusama's own engagement with death and infinity. I conclude by looking briefly at the deaths of Michael Brown and Robin Williams, and again at my own grief one year after Zoë's death.

abstract: Thesis

abstract: Master of English


title: Analysis of the Role of TRF1 Phosphorylation and TRF1 Domain Structure in Alternative Lengthening of Telomeres Activity

contributor:
Zhu, Xu-Dong
Biology

abstract: Telomeres are heterochromatic DNA-protein structures that protect the ends of linear chromosomes from being recognized as sites of DNA damage and help maintain genomic integrity. The shelterin complex that binds telomeres is vital for regulating telomere length and function, disruption of which can lead to ageing and tumorigenesis. About 90% of human cancers activate telomerase to maintain telomere length, which allows these cells to have unlimited proliferation. The remaining 10% of cancers use a telomerase-independent mechanism that relies on homologous recombination for telomere synthesis, known as alternative lengthening of telomeres or ALT. TRF1, a component of the shelterin complex that binds directly to telomeric DNA, has been implicated in telomere maintenance in both telomerase-positive and negative cancer cells. The function of TRF1 is regulated in part by post-translational modifications, such as phosphorylation. TRF1 phosphorylation at T371 has been implicated in regulating TRF1 functions in mitosis and in the repair of DNA double strand breaks in telomerase-positive cells. The results presented in this thesis demonstrate that TRF1 phosphorylation at T371 is also important in ALT cells and is regulated by DNA damage response factors. T371 phosphorylation is required for the functional assembly of ALT-associated PML bodies and the production of C-circles, which are hallmarks of ALT cancer cells. The results presented in this thesis also suggest that the dimerization and DNA binding capabilities of TRF1 are required for the functional assembly of ALT-associated PML bodies. The work presented here identifies a novel role of TRF1 in ALT activity, which provides further insight into telomere regulation mechanisms in this subset of cancer.

abstract: Thesis

abstract: Master of Science (MSc)


title: Women, Work, and God: The Incarnational Politics and Autobiographical Praxis of Victorian Labouring Women

contributor:
Kehler, Grace
English and Cultural Studies

subject:
Victorian Britain
working-class autobiography
feminist theology
women's writing
labour
gender

abstract: My dissertation examines the cross-class relations of Victorian women separated by social status but brought together by their faith in a subversive Christian God who supports female labour. Using original archival research, this project documents the untold story of working-class women and their middle-class allies who challenged patriarchal interpretations of Christian theology and, particularly, the limitations placed on women’s material lives. Drawing on Victorian social thought, feminist autobiography theory, and contemporary body theology, my project pursues two complementary objectives. The first aim is to bring the neglected voices of working-class women into the debates about gender, labour, and cross-class relations that defined the Victorian period. The second is to trace the origins of a feminist “theology from below,” which, born out of the material grittiness of everyday life in the nineteenth century, emphasized the incarnational nature of all bodies, including those labeled dirty, disabled, and perverse. My first two chapters respectively explore the diaries of two well-known Victorian women, Josephine Butler and Hannah Cullwick. Both reconfigure Christian discourses of mission and servitude, seeking not only agency within their positions of subjugation but also new models of relationality. The final two chapters bring together the voices of Jane Andrew (a farm worker) and Ruth Wills (a factory worker) with the writings of fin-de-siècle Christian socialists to construct a politics of redemption based on an ethics of inter-relation that, instead of positioning some bodies as “godly” and others as in need of “saving,” recognizes the immanent divine spirit animating all material life. Using contemporary feminist theology to strengthen the incarnational politics found in these Victorian writings, I argue in favour of bodily transgression—the willingness to walk, talk, touch, and labour in ways that are thought to be “perverse” and “ungodly”—as a legitimate answer to Christ’s call to defy social hierarchies, especially the ones established by capitalist modernity.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Impact of Informative Censoring on Statistics Used in the Validation of Surrogate Endpoints in Oncology

contributor:
Pond, Gregory
Mathematics and Statistics

subject:
informative censoring
surrogate endpoint

abstract: In the past few years, biomarkers such as progression free survival (PFS)  and time to progression (TTP), have been increasingly used as surrogate endpoints for overall survival (OS) in clinical trials in oncology. An issue occurs when clinical trials which demonstrated statistically significant treatment effect for the surrogate marker, shows no significant effect on the true outcome of interest, OS. It is possible that this lack of concordant results was due to informative censoring. Although it is known that informative censoring may bias the observed results, it is not clear what impact informative censoring has on the surrogacy of one marker in relation to a true outcome. In this thesis, we investigated how informative censoring could affect the results of a surrogate endpoint, and how would that affect the surrogacy of that endpoint. A simulation study was conducted to evaluate the impact of informative censoring on the treatment effect on TTP and the outcomes of the surrogate validation methods relative effect (RE), surrogate threshold effect (STE), and the difference between the treatment effect on TTP and on OS (IRE). The results of the simulation showed that having informative censoring for TTP will indeed bias the treatment effect on TTP as well as the results for the validation methods, RE, STE, and IRE. Hence, we conclude that the effect of informative censoring can greatly influence the ability to validate a surrogate marker, and additionally can bias the ability to determine the efficacy of a new therapy from a clinical trial using a surrogate marker as the primary outcome.

abstract: Thesis

abstract: Master of Science (MSc)


title: Double Rotor Switched Reluctance Machine with Segmented Rotors

contributor:
Emadi, Ali
Schofield, Nigel
Mechanical Engineering

subject:
Switched reluctance machine
Double rotor electric machine

abstract:
Double rotor machines, appearing in versatile forms and configurations thanks to the great flexibility of having a pair of rotors, are seen in a number of applications. Double rotor machines show promising prospect in the application of advanced hybrid electric vehicle powertrains due to the requirement of dual electro-mechanical ports in such systems. Integrating these powertrain systems with double rotor machines not only brings design freedom of laying out components, but also reduces number of parts and thus improves compactness. The switched reluctance type double rotor machines, offering unique characteristics of having a simple structure and no permanent magnets, are strong candidates for high performance applications.
     In this thesis, a family of double rotor switched reluctance machine with segmented rotors is proposed and studied. Compared to double rotor switched reluctance machines with a more conventional structure, the proposed designs exhibit potentials of achieving higher compactness and performance. A prototype double rotor machine of the segmented rotor design is constructed and tested to benchmark an existing double rotor switched reluctance machine. The experiment results show that the proposed design is able to achieve the same output with similar or higher efficiency than the benchmark machine, while occupying only about 60% of overall volume. The double segmented rotor switched reluctance machine demonstrates to be a promising double rotor topology and is worth further research.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Short-course antimicrobials for the treatment of paediatric pneumonia

contributor:
Loeb, Mark
Health Research Methodology

subject: pneumonia, antimicrobial, treatment

abstract:
Paediatric community-acquired pneumonia (CAP) is common in North America. It is often treated with beta-lactam antimicrobials targeting S. pneumoniae, the most important cause of CAP in young children. Current guidelines recommend 10 days of therapy for paediatric CAP, regardless of severity; in contrast, mild CAP in adults is routinely treated with only 5 days of antimicrobials. There have been no definitive studies of 5-day vs. 10-day therapy for CAP in children.
The objective of this thesis was to conduct a pilot RCT comparing 5 to 10 days of amoxicillin for the treatment of mild paediatric CAP and then design the multicentre follow-up trial.
Children aged 6 months - 10 years with no significant past medical history presenting to the McMaster Children's Hospital emergency department with mild CAP were eligible for enrollment. All participants were randomized to either 10 days high-dose amoxicillin (90 mg/kg/day divided bid) or 5 days of high-dose amoxicillin + 5 days placebo. The primary outcome was clinical cure at day 14-18 post-enrollment.
In total, 61 participants were recruited. The median participant age was 2.64 y. Only 60% of chest radiographs were reported by the radiologist as showing evidence of pneumonia. There were six treatment failures; one participant failed to defervesce on day 4, one participant had recurrent fevers leading to re-presentation to the emergency, and the other four participants did not meet clinical cure criteria but were essentially well at the time of follow-up. Study blinding has been maintained.
The majority of previously healthy children with mild CAP who are well enough to be treated as outpatients appear to do well, regardless of duration of antimicrobial treatment. Feasibility and safety of the trial protocol have been demonstrated; the follow-up multicentre trial is slated to begin in mid-2015.

abstract: Thesis

abstract: Master of Science (MSc)


title: PROPOSED AQUIFER VULNERABILITY ASSESSMENT INCORPORATING FRACTURED ROCK

title: PROPOSED AQUIFER VULNERABILITY ASSESSMENT INCORPORATING CHARACTERIZATION OF FRACTURED ROCK ENVIRONMENTS IN SOUTHERN ONTARIO

contributor:
Dickson, Sarah E.
Guo, Yiping
Civil Engineering

subject:
vulnerability mapping
fractured rock
groundwater protection
Ontario

abstract:
Much of southern Ontario relies on groundwater in fractured rock aquifers as a municipal drinking water source, thus the vulnerability of these sources is of importance from public health, economic, and environmental perspectives. Aquifer vulnerability assessments serve as visual communication tools useful in efficiently allocating resources for the establishment of new drinking water sources, hydrogeological characterization, and source water protection planning decisions. Examples of current vulnerability assessments include: DRASTIC, GOD, EPIK, AVI, COP and ISI. These vulnerability assessment methods either fail to quantitatively incorporate characteristics of fractured rock and preferential pathways, or they account for only heavily karstified areas; none are suited to the fractured rock formations in Ontario.
The goal of this work is to incorporate fractured rock characteristics in a new aquifer vulnerability assessment method using readily attainable quantitative data to produce an inexpensive and straightforward regional aquifer vulnerability map highlighting hydrogeological areas that are more fundamentally prone to contamination than others. This proposed method is applied to the Acton-Georgetown study area in southern Ontario, along with the AVI and DRASTIC methods for comparison. The AVI and DRASTIC vulnerability assessments yield very different results from each other, and the proposed method demonstrates the heavy influence that fractured rock has on the vulnerability of the study area. The heterogeneity of variables used in some of the methods created difficulty in the interpolation of point data, rendering the use of generalized spatial data more valuable. These results and the corresponding limitations and recommendations for future improvements are discussed in light of these conclusions.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Where Heaven Touched Earth: Encountering Place and Person at Lourdes

contributor:
Badone, Ellen E.F.
Religious Studies

abstract:
Based on ethnographic fieldwork conducted with pilgrims travelling from the United Kingdom to the Marian Catholic shrine of Lourdes in south-western France, this study examines the experience of contemporary pilgrims to Lourdes and the motivations that inspire them to visit the shrine. As a pilgrimage site that now attracts an estimated six million visitors each year from a diverse range of geographical, social, and religious departure points, the motivations inspiring pilgrims to visit Lourdes can be elusive and disparate.
From volunteer caregivers striving to “be as Christ” through their assistance to sick pilgrims, to first-time visitors to Lourdes navigating the shrine through the camera lens of a Hollywood film, this study moves through a wide range of pilgrim experiences. While such experiences underscore the inherently multivalent nature of pilgrimage, I show how the trope of authenticity emerges as a rhetorical device that recurs frequently in the narratives and discourse of pilgrims who undertake the journey to Lourdes. Experiences described by pilgrims as “authentic” are critical in informing their engagement with the geography of the shrine and with fellow pilgrims, and often inspire return visits to Lourdes in subsequent years.
In dialogue with studies on pilgrimage and other forms of travel, I argue that despite its conceptual baggage authenticity still matters, and offers a useful heuristic lens for exploring those factors which shape and determine the experience of pilgrims to Lourdes. I suggest that from the perspective of pilgrims, Lourdes is a “thin space” where heaven touched earth and which affords the authentic possibility of transcendence, of collapsing the boundaries between self and other, human and divine.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Application of ancient DNA methodologies to forensic science

contributor:
Poinar, Hendrik
Biology

subject:
Ancient DNA
Forensic science
High throughput sequencing
DNA repair

abstract: Forensic scientists and ancient DNA researchers face similar challenges with respect to genetic information acquisition and analysis. However, these communities differ in one critical aspect: while forensic science is regulated by the strict guidelines of the judicial community, ancient DNA is a research-based academic field free to explore emerging technologies as they arise. This thesis investigates the application of two methodologies, developed in ancient DNA research, to challenging extracts, in hopes of modernizing forensic models while maintaining compatibility with current standards. The first chapter focuses on blunt-end sequencing library preparation protocols previously optimized for ancient DNA specimens. Forensically-relevant extracts were converted into libraries and typed by short tandem repeats (STR) amplification. When compared to STR profiles from pre-library extracts, a significant decrease in the quality was observed, in the form of allelic drop-out, heterozygous peak imbalance and increased stutter ratios. The second chapter discusses the efficacy of two enzymatic DNA repair methods, “PreCR® Repair” and “Nelson”, on typical ancient DNA specimens. Based on endogenous sample content, fragment length variation and base misincorporation rates, some DNA repair was reported when using PreCR®. However, the use of the Nelson protocol is not recommended for use in its current state. Both sequencing library preparation and enzymatic DNA repair show potential application to forensic evidential material, but require further analyses to confirm hypotheses and observations outlined in this thesis.

abstract: Thesis

abstract: Master of Science (MSc)


title: A Monte Carlo Investigation of Smoothing Methods for Error Density Estimation in Functional Data Analysis with an Illustrative Application to a Chemometric Data Set

contributor:
Racine, Jeffrey S.
Statistics

subject:
Nonparametric
Bayesian
Smoothing
Splines
Kernel
Spectrometric data

abstract:
Functional data analysis is a  eld in statistics that analyzes data which are dependent
on time or space and from which inference can be conducted. Functional data
analysis methods can estimate residuals from functional regression models that in
turn require robust univariate density estimators for error density estimation. The
accurate estimation of the error density from the residuals allows evaluation of the
performance of functional regression estimation. Kernel density estimation using
maximum likelihood cross-validation and Bayesian bandwidth selection techniques
with a Gaussian kernel are reproduced and compared to least-squares cross-validation
and plug-in bandwidth selection methods with an Epanechnikov kernel. For simulated
data, Bayesian bandwidth selection methods for kernel density estimation are
shown to give the minimum mean expected square error for estimating the error density,
but are computationally ine cient and may not be adequately robust for real
data. The (bounded) Epanechnikov kernel function is shown to give similar results as
the Gaussian kernel function for error density estimation after functional regression.
When the functional regression model is applied to a chemometric data set, the local
least-squares cross-validation method, used to select the bandwidth for the functional
regression estimator, is shown to give a signi cantly smaller mean square predicted
error than that obtained with Bayesian methods.

abstract: Thesis

abstract: Master of Science (MSc)


title: Sortase enzymes and their integral role in the development of Streptomyces coelicolor

contributor:
Elliot, Marie
Biology

subject:
Streptomyces
molecular biology
sortase

abstract:
Sortase enzymes are cell wall-associated transpeptidases that facilitate the attachment of proteins to the peptidoglycan. Exclusive to Gram positive bacteria, sortase enzymes contribute to many processes, including virulence and pilus attachment, but their role in Streptomyces coelicolor biology remained elusive. Previous work suggested that the sortases anchored a subset of a group of hydrophobic proteins known as the long chaplins. The chaplins are important in aerial hyphae development, where they are secreted from the cells and coat the emerging aerial hyphae to reduce the surface tension at the air-aqueous interface.
Two sortases (SrtE1 and SrtE2) were predicted to anchor these long chaplins to the cell wall of S. coelicolor. Deletion of both sortases or long chaplins revealed that although the long chaplins were dispensable for wild type-like aerial hyphae formation, the sortase mutant had a severe defect in growth. These two sortases were found to be nearly redundant, as deletion of individual enzymes led to only a modest change in phenotype. In vitro analysis of sortase cleavage activity showed that both sortases recognized the unique LAXTG pentapeptide sequence found in the long chaplins, and 11 other putative substrate proteins.
Transcriptional analysis revealed that a number of genes typically expressed during aerial hyphae development were not expressed in a sortase deletion mutant. This suggests that the sortases have a role in transcriptional regulation, a phenomenon that has not been described previously. Current work is focused on addressing the mechanism(s) by which sortases affect transcriptional regulation, with a specific focus on the role of the proteins that they anchor to the cell wall (sortase substrates) in aerial growth.

abstract: Thesis

abstract: Master of Science (MSc)


title: Droplets, Films and Edges: Studies of the Physical Character of Diblock Copolymers

contributor:
Dalnoki-Veress, K.
Physics

subject:
block copolymer
fluid
droplets
optical microscopy
atomic force microscopy
Flory-Huggins interaction parameter
thin films
lamellar edges

abstract:
Block copolymers, long chain molecules of two distinct chemical species joined
covalently to one another, have long been known to form organized structures on the nanoscopic level. For example, if the two chains are the same length a lamellar structure results . In this work we show how this internal structure causes distinct deviation from 'normal' fluid behavior. We begin with the observation of block copolymer droplets with atomic force microscopy. We note the droplets form nearly conical shapes in stark contrast to the usual spherical cap. These droplets are found t o spread at an incredibly slow speed, and to have interesting instabilities in their wetting layer. We move on to studies of completely wet substrates (i.e. thin films) near the order-disorder transition of the material. Here we directly observe, with optical microscopy, a change in the fundamental spacing of the diblock's internal structure. This represents a superior method of measurement of the Flory-Huggins interaction parameter, which we verify in several ways. We also use the change in lamellar thickness to drive diffusion from one layer to another, and by similar measurements we can determine the kinetics of diffusion between the lamellar layers. In the last study we measure the lamellar edges on a gradient thickness sample with optical microscopy. In so doing we can directly observe surface induced ordering, and for the first time, can precisely resolve the near surface ordering dynamics.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Nanostructures for Donor-Acceptor Pair Luminescence

contributor:
Kitai, A. H.
Materials Science

subject:
nanostructured powder EL device
nanowires
luminescence
donor-acceptor pairs

abstract:
Commercial success had been achieved with electroluminescent phosphor
powders, particularly zinc sulfide activated with copper. The applications of AC
Powder EL (ACPEL) are mainly limited to backlighting and lamp applications that require low brightness. This includes low illumination environments, such as nightlights and backlighting for LCDs and keypads in portable electronics and home electronics. By using nanowires as nanoelectrodes, a novel and self-supported nanostructured powder EL device has been developed in this thesis. The novel structure contains a single layer of ZnS:Cu powder phosphor which is embedded in a polymer matrix with one surface exposed. A dilute layer of conductive nanowires directly contacts the phosphor layer and works as rear electrodes. A highly intensified electric field can be induced in the phosphor region by the metal nanowires if a specific voltage is applied
to the device. Simulations of the electric field by using commercial software show that the localized electric field can be at least one order of magnitude higher than the average field depending on the dimensions of the nanowires. As a result, electrons can be injected into the phosphor lattice by high-field-assisted tunneling, hence inducing electron avalanching. The electrons finally are trapped at the donors. When the external field is reversed, the electrons recombine with the holes that are previously injected by the same process and trapped at the acceptors. Therefore, visible light is produced by the recombination of the electron-hole pairs through the donor-acceptor pairs.
The indium nanowires, with diameters of 300 nm and lengths of several microns, have been fabricated by using anodic aluminum oxide (AAO) templates which are known as self-organized porous structures formed by anodization of aluminum in an appropriate acid solution. A hydraulic pressure injection method has been applied to inject molten indium metal into the nanopores of the AAO template and form nanowires. By dissolution of the template, a large number of free indium nanowires is obtained. The nanowires are transferred onto a ZnS-embedded substrate by a wet-coating method. Finally, the entire device is completed by deposition of Au rectangular electrodes on the top of the indium nanowires. The indium nanowires have been characterized by using SEM and XRD. The tests of the dependence of luminance on voltage at various frequencies for a nanowire contact EL device sample are performed. A peak luminance of 25 cd/m2 has
been achieved for the device driven at frequency of 8.2 kHz and a voltage of 425 V. The EL performance of the nanowire contact EL device is not as good as traditional powder EL devices so far, however, the novel structures have the potential for a lower operating voltage with simultaneous long lifetime and high luminance to overcome limitations of traditional powder EL.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: MODCONV: A Computer Code to Predict the Local Velocities and Temperatures Inside a Moderator

subject:
MODCONV
FORTRAN
donor cell finite differencing scheme
moderator
velocity
temperature

abstract:
MODCONV is a FORTRAN Computer code using the primitive form of the conservation equations for natural convection in porous medium to calculate the velocity and temperature distribution in the moderator of a typical CANDU
reactor under normal and shut down operations, as well as postulated LOCA for which the rupture in the system is external to the core. Appropriate velocities are imposed at the boundary walls so that the free convection equations set can be used to model a mixed convection problem. Purely explicit, donor cell finite differencing scheme is used. A heat exchanger model using NTU method is also included to give a realistic inflow temperature for the moderator. The heat load distribution is calculated according to a channel
power map, but can be redefined through input.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: The Geographical Aspects of Historical Newspaper Advertising

contributor:
Gentilcore, R. Louis
Geography

subject:
newspapers
advertisement
commercial
historical geography

abstract:
Newspapers were and are source of information. As permanent communicative tools, they bear mute witness to the occurrences of past and present. On their page are printed important events, great plans, and inconsequential happenings. And yet, newspapers are much more than mere disseminators of news, for they also offer commercial information, and as such, supply their readers with a veritable directory of neighboring merchants.
Through its advertisements, the newspaper makes available at a glance, the location and price of the various goods and services of which the newspaper reader may have need. This is true of present day newspapers, and it is true of past newspapers. These advertisements may expound the advantages of a shop in the town in which the newspaper is based, or it may give the newspaper reader information about a commercial establishment outside of that town. These advertisements offer information about not only the merchant's store, but also about the merchant. That he sent an advertisement to any newspaper, says something about him; but that he sent it to that particular newspaper, says even more. This study aspires to define that "even more". In trying to define that phrase, the author hopes to introduce newspaper advertisements as a source of data for historical geographers. As such, this study is a continuation of several previous investigations carried out on historical newspaper advertisements by other researchers, and a paper presented by the present author. There are various types of studies which can be done using this data as a primary source. Some of these studies will be investigated in great detail in this paper; others will be merely mentioned. It is hoped that through this paper, the validity of this data source will be established, and the various problems or pitfalls will be defined.

abstract: Thesis

abstract: Master of Arts (MA)


title: Paraspinal soft tissue layer differential movement from spinal manipulative therapy preload forces

contributor:
Triano, John. J.
Rehabilitation Science

subject: Spinal manipulation, preload, ultrasound elastography,

abstract:
Introduction: Implicit within spinal manipulative therapy is the assumption that treatment loads are effectively transcribed to actuate consistent mechanisms for expected clinical results. There is conflicting evidence between the mechanistic understandings and the physiologic responses from experimental evidence. Greater clarity on how loads are transferred through tissues to the target sites would be useful in enhancing utilization and efficacy of spinal manipulative procedures.
Purpose: Directly monitor displacement of tissue in strata at sequential depths between the load application site and target articulation in the thoracic spine. Tissue displacement served as a surrogate for evidence of load transmission.
Methods: Ultrasound elastography techniques monitored displacement in sequential strata while electromyographic signals, force, kinematic motions were monitored synchronously. Volunteers were placed prone on a treatment table, while a typical spinal manipulative pre-load maneuver was applied in the thoracic spine.
Results: When applying a therapeutic load to the skin the results demonstrate with increasing depth of tissue there is a sequentially decreasing rank order in the mean cumulative displacement with each layer being significantly greater than the deeper adjacent layer. Superficial loose connective tissue layer (0.34 mm ± 0.15) vs. intermediate muscle layer (0.28 mm ± 0.11), p=0.004. Intermediate muscle layer (0.28 mm ± 0.11) vs. deep muscle layer (0.16 mm ± 0.6), p<0.0001.  Filtered myoelectric signals were linearly correlated with tissue strata cumulative displacements,
but the relationship was not strong (-0.23 < r < 0.46).  Conversely, Pearson correlation analysis revealed strong and relatively stable correlations (0.74 < r < 0.90) for the association between displacement at the load application site and tissue layers.
Conclusion: The sequential tissue motion demonstrates that some degree of load transfer through layers occurs. Both direct and indirect stimulation of tissues across both depth and breadth is feasible, to an extent consistent with the stimulation of mechanoreceptors.

abstract: Thesis

abstract: Master of Science (MSc)