title: No Longer Your Token Indian: Indigenous Stories of Navigation Through the Education System

contributor:
Davis, Jennifer
Education

subject:
Indigenous Methodology
Indigenous Education
Indigenous Storytelling

abstract: This research provides a platform for four Indigenous students to share their stories and experiences whilst leaving their home First Nation communities to further their education. Utilizing narrative inquiry and Indigenous storywork approaches, the purpose of this thesis was to create a safe space for students to discuss the adjustments they were required to make; successes they experienced, as defined by them; barriers and obstacles they faced, as identified by them; support they received, as well as, sharing their ideas as to what could make the journey easier for those coming behind them. Their stories were shared through open-ended conversations, and are presented here in both story form, and in their own words. It is through the relationship built between the reader and the stories that true connection and meaning are made, allowing the spirit of the stories to create discussion and change.

abstract: M.Ed.


title: Essays on Asset Prices

contributor:
Head, Allen
Milne, Frank
Economics

rights: Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada

rights: ProQuest PhD and Master's Theses International Dissemination Agreement

rights: Intellectual Property Guidelines at Queen's University

rights: This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.

subject:
Exchange Rates
Commodity Prices
House Price Expectations
Rational Inattention

abstract: This thesis contains three essays spanning the fields of commodity currency prediction and house price sentiment. This first essay examines the long-run relationship between the real price of crude oil and the real exchange rate for Canada. The real Canadian exchange rate is found to be positively correlated with the real price of crude oil beginning in 2002-2003, which implies that in the long run, Canada’s real exchange rate varies with the level of the real oil price. Furthermore, the long-run adjustment of the real exchange rate is found to be via the nominal exchange rate, which implies that real exchange rate movements can forecast movements in the nominal exchange rate. The second essay studies households’ expectations of the house price growth and finds three dimensions of heterogeneity which are consistent with Sims' (2003) rational inattention theory, namely the heterogeneity in households' mean forecasts, in the perceived precision of households' forecasts, and in their dynamic forecasting rules. The third essay investigates whether households' expectations of future home price growths react to the information about past home price growths differently over different horizons. I find that households' expectations display an extrapolating pattern from the past growth over the short term (12-month) and a mean-reverting pattern over the longer term (5-year).

abstract: PhD


title: Data-Driven Bottleneck Identification for Serial Production Lines

contributor:
Mechefske, Chris K.
Mechanical and Materials Engineering

subject:
Applied Machine Learning
Data Science
Production Improvement
Manufacturing System
Maintenance
Process Bottlenecks

abstract:
Bottleneck identification is an important challenge for manufacturing firms to address in pursuit of increased manufacturing capacity. Prominent efforts used simulation-based approaches but are seldom extended to industry due to lack of data availability. This thesis presents an application of three methods to an industrial data set. A data pipeline was developed to automate data collection from machinery, which was used to realize the first data-driven application of bottleneck identification methods in the electronics industry. It was determined that three methods agreed on the identified bottleneck machine for just 8% observed production runs.

Once different perspectives on bottleneck machines were explored, diagnostic insights were sought to identify root causes of capacity loss. Fault events collected by the data pipeline were analyzed using first principles and unsupervised learning techniques. Four data visualization approaches were explored, and a web interface was developed to communicate these insights. The principal causes of unplanned downtime were identified and aligned with domain knowledge at the case company.

Improved data quality will improve the quality of bottleneck identification results, and further data collection will improve the understanding of fault behaviour. Ultimately, the work reveals the opportunities and challenges associated with data-driven applications in manufacturing.

abstract: M.A.Sc.


title: Biodiesel Production and Purification with a Hydrophobic Sintered Glass Filter

contributor:
Liu, Guojun
Chemistry

rights: Attribution-NonCommercial 3.0 United States

subject:
Biodiesel
Hydrophobic coatings
Water and oil separation
Octadecyl trichlorosilane

abstract: Octadecyltrichlorosilane (OTS) has been chemically grafted onto sintered glass filters to render them hydrophobic.  These hydrophobic filters were subsequently employed for the purification of biodiesel.  Various properties of the OTS-coated sintered glass filters were evaluated, such as the water contact angle, water sliding angle, solvent flux, and the breakthrough pressure.  These characterizations revealed that the highest breakthrough pressure was achieved when the OTS had been applied onto the filters by means of a toluene coating solution with an OTS concentration of 1.9 vol %.  The biodiesel employed in this investigation was synthesized from methanol and cooking oil via a base-catalyzed transesterification reaction.  Glycerol and fatty acid salts were obtained as side products via this transesterification reaction.  The excess unreacted methanol was first removed by rotary evaporation, and hydrochloric acid (HCl) was then mixed with the biodiesel to neutralize the fatty acid salt and to coarsen the glycerol droplets.  After sedimentation, water was added into the biodiesel to enable the formation of a water/glycerol phase and to reduce the glycerol concentration in the biodiesel.  Optimization experiments revealed that the addition of water to the biodiesel at a concentration of 1.00 wt % provided the optimum effect, with no significant reduction of the glycerol content being achieved at higher water concentrations.  The water/glycerol phase was removed by the OTS-coated sintered glass filter under a vacuum of 30 mbar.  A relatively constant flux of 34.1± 0.6 L/m2 h was achieved during the course of the separation process.  Karl Fisher titrations revealed that the water concentration in the biodiesel permeate primarily remained constant as the separation progressed.  However, the filter did not offer reproducible results when the separation experiments were repeated during different times of the year, possibly due to differences in the humidity.  The hydrophobic filters introduced here may be candidates for the separation of oil/water mixtures.

abstract: M.Sc.


title: Automated classification of electrosurgical cautery state

contributor:
Fichtinger, Gabor
Ungi, Tamas
Computing

subject:
Electrosurgical cautery
Oscilloscope
Machine learning
REIMS
Breast conserving surgery

abstract: Introduction: In computer assisted surgery, it is sometimes necessary to detect when an activated electrosurgical tool comes into contact with a patient, known as the energy event. By continuously tracking the electrosurgical tools’ location using a navigation system, these energy events can help determine locations of sensor-classified tissues of interest. Our objective is to detect the energy event and settings of a cautery robustly and automatically with a technique that does not disrupt the surgical workflow. This study aims to demonstrate the feasibility of detecting the cautery state during surgical incisions. Methods: I detected changes in the current in the cautery cables using a current sensor and an oscilloscope. I implemented a custom 3D Slicer module that uses machine learning to automatically detect energy events, the cautery’s mode, and cautery settings with no change to the surgical workflow. Results: The model was robust in classifying each cautery state with high accuracy, regardless of the different tissue types and power level parameters altered by users during an operation. The model was also able to detect the power level of the cautery. Conclusion: The results demonstrate the feasibility to automatically identify when surgeons make incisions during their operation.

abstract: M.Sc.


title: Social Movements in Gold Mining in Africa: A Community Guide to Strategic Action

contributor:
Goebel, Allison
Environmental Studies

subject:
Social Movement
Environmental Justice
Gold Mining
Africa

abstract: The resource extraction industry, especially gold mining in Africa, generates various negative social and environmental impacts, including biodiversity loss, deforestation, groundwater contamination and displacement of communities. These long-term and damaging impacts often cause discontent in the communities directly impacted by the activities of the mine and conflicts between the companies and the communities. In response, social movements have emerged in which communities either protest to stop mining or request to be part of the decision-making processes. Social movements have emerged with an important role as regulators and promoters of transformative sustainable development agendas. Social movements have great potential to strengthen, create and generate supportive policies for their communities. This thesis analyzes conflicts between mining companies and impacted communities in Africa and the various forms of community actions, social movements and activism used by communities and NGOs in response to these impacts. Considering the broader literature on such conflicts, this research then focuses on two case studies of these contemporary movements in Tanzania and Ghana. The thesis analyzes how communities close to the North Mara Gold mine in Tanzania and the Obuasi AngloGold Ashanti Gold mine use different community-led actions to protest mining activities in their communities. Using an extensive literature review and document analysis which allowed for an enhanced exploration and interpretation of the case studies, the most effective forms of protest adopted by these groups were identified. This was done with a specific interest in materials that intersected with the themes and the various forms of community actions: advocacy, public engagement, and collaborative process. With the lessons learned and the different advocacy frameworks analyzed, critical characteristics of a practical social movement framework will be recommended for community-based social movement groups. These key characteristics which include framing, motivation, public visibility, urgency emerging leaders and individual and collective actions can help guide social movement groups. This thesis provides a deep analysis of the relationship between environmental justice and social movements and reveals the importance of a practical social movement framework.

abstract: M.E.S.


title: Bites and Bytes: An Investigation of Virtual Food Programming during the COVID-19 Pandemic

contributor:
Prouse, Carolyn
Geography and Planning

rights: Attribution-NonCommercial-ShareAlike 3.0 United States

subject:
Food security
Food literacy
Student food security
Geographies of care
Virtual geographies
Institutional geographies of care

abstract: During the COVID-19 pandemic, the Cooking with Grammas programming at Queen’s University was moved online. Following the initial success of the program, a second cooking program, Cooking with Chaplains, was started in the fall of 2020. In these programs, students joined together with the hosts (Grammas or Chaplains, respectively) to cook and eat a meal together over Zoom. These programs aim to address student food insecurity and illiteracy, and a lack of community on campus. In my thesis, I investigate the two programs in conversation with literature related to care and geographies of care, food and wellbeing, and the creation of the self in virtual space. I analyze 14 interviews from both leaders and participants of the Cooking with… programming. Ultimately, I found that the Cooking with… programming was an essential tool for international students navigating Kingston’s foodscapes for the first time; however, the biggest impact of the program was to provide community and a sense of connection during the pandemic. I conclude my thesis with four recommendations for others looking to run similar programs in the future: investigate hybrid programming options, provide a consistent format, demonstrate openness, and consider how to provide care to the leaders themselves.

abstract: M.A.


title: Religion in the Aspirations-(Cap)abilities Framework of Migration: A Case of Ghanaian Emigration and Integration in Canada

contributor:
Epprecht, Marc
Cultural Studies

subject:
Migration aspirations
Migration capabilities
Integration in Canada
Black religions in Canada
Ghana
African immigrants in Canada
African Pentecostalism
Religion in African migration

abstract:
Over the last three decades, there has been extensive research on religion and migration. Yet,
 existing approaches focus more on the consequences of migration in destination countries than the conditions that generate migration in the first place. This study argues that new insights can be gained when scholars address separately how religion emerges, first, in the aspiration to migrate; second, in the (cap)ability to move; and finally, in the settlement and integration of immigrants. Using mixed methods involving observations, online surveys (N=642), and fifty interviews, the study explores the nature and role of Christianity in Ghanaian emigration and integration into Canada. The analysis of migration aspirations shifts the study of religion from actual migration in the present to imagined migration in the future. This shift draws attention to experiential dimensions of religion—dreams, prophecies, and intuitions—which subvert rational economic motives, or external push and pull factors of migration. The analysis of religion in the cap(ability) to move highlights the important role of religious resources that show how migrants are differently equipped to overcome barriers to migration. Finally, the cases of Ghanaian Christian immigrants in Ontario posit integration and immigrant religion as middle grounds where structure and agency meet. Challenging stereotypical notions of poverty-driven African emigration, this study provides relevant knowledge of development-driven African emigration and the crucial role religion plays in the migratory process.

abstract: PhD


title: The Exponential Map for Time-Varying Vector Fields

contributor:
Lewis, Andrew
Mathematics and Statistics

rights: Attribution-ShareAlike 3.0 United States

subject:
Exponential map
Time-dependent vector fields
Parameter-dependent vector fields
Local flows
Control systems
Geometric analysis

abstract:
The exponential map that characterises the flows of vector fields is the key in understanding the basic structural attributes of control systems in geometric control theory. However, this map does not exist due to the lack of completeness of flows for general vector fields.

An appropriate substitute is devised for the exponential map, not by trying to force flows to be globally defined by any compactness assumptions on the manifold, but by a categorical development of spaces of vector fields and flows, thus allowing for systematic localisation of such spaces. That is to say, we give a presheaf construction of the exponential map for vector fields with measurable time-dependence and continuous parameter-dependence in the category of general topological spaces. Moreover, all regularities in state are considered, including the cases of continuous, finitely differentiable, smooth and holomophic. Using geometric descriptions of suitable topologies for vector fields and for local diffeomorphisms, the homeomorphism of the exponential map is derived by a uniform treatment for these regularities. Finally, a new sort of continuous dependence is proved, that of the fixed time local flow on the parameter which plays an important role in the establishment of the homeomorphism of the exponential map.

abstract: PhD


title: Towards Bridging the Navigation Gap in Ultrasound-Guided Prostate Biopsy

contributor:
Fichtinger, Gabor
Computing

subject:
Prostate Biopsy
Deep Learning
Low-cost
Ultrasound
Surgical Navigation
Open-source

abstract:
Global disparities in access to advanced imaging modalities and navigational systems have exacerbated existing differences in prostate cancer diagnosis and prognosis worldwide. As a result, a clear navigational gap has emerged between clinicians that have access to MRI data during prostate biopsy and those that do not. Enabling technologies, such as spatially-tracked ultrasound and deep learning, have the potential to help bridge this gap and improve prostate biopsy yield in low resource settings. The objective of this thesis is to develop a technique for extending the diagnostic utility of trans-rectal ultrasound guidance during prostate biopsy. The principle contributions presented here are the design, implementation and testing of a system capable of generating a 3D model of the prostate from spatially-tracked 2D ultrasound images.

A trained deep learning network was used to identify the prostate within 2D trans-rectal ultrasound images, while a spatially tracked probe enabled the 3D localization of prostate segmentations and subsequent generation of a 3D prostate model. The system was developed using open-source software and low-cost materials, and a user study was conducted to evaluate the accuracy of the prostate reconstruction. The results indicated comparable performance between this low-cost system and more expensive mechanically-tracked methodologies.

The capacity to generate a 3D prostate model using readily available technologies has the potential to improve access to navigated biopsy in low resource settings. Future work will focus on using the 3D prostate reconstruction to overlay zonal information on 2D ultrasound images, helping clinicians visualize the zones of the prostate and more evenly place biopsy cores within the gland. Low-cost navigational tools have an important role to play in democratizing access to reliable prostate cancer diagnosis and reducing the burden of disease among those most affected by prostate cancer.

abstract: M.Sc.


title: What is the role of phosphorylation of the Ca2+/calmodulin-dependent glutamate decarboxylase isozyme, AtGAD1, in response to phosphate nutrition of Arabidopsis thaliana?

contributor:
Plaxton, William
Snedden, Wayne
Biology

subject: Biochemistry GABA Plants phosphate

abstract: Orthophosphate (H2PO4−; Pi) is an essential but limiting macronutrient required for many fundamental aspects of plant metabolism, particularly photosynthesis and respiration. Pi starved (-Pi) plants elicit a Pi starvation response that alters gene expression and metabolism to enhance their efficiency of Pi acquisition and use. We recently employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to assess the impact of Pi nutrition on the phosphoproteome of cell cultures of the model plant Arabidopsis thaliana. Forty-eight hours following Pi resupply to -Pi cells, the glutamate decarboxylase isozyme AtGAD1 (AT5G17330.1) became in vivo hyperphosphorylated at multiple seryl residues near its N-terminus. AtGAD1 is a root-specific, Ca2+/calmodulin-activated cytosolic isozyme that catalyzes the first committed step of the γ-aminobutyrate (GABA) shunt by decarboxylating glutamate into GABA. Although phosphoproteomic studies have documented widespread plant GAD phosphorylation, there have been no reports on the functions nor mechanisms of plant GAD phosphorylation. Here, I developed and validated a spectrophotometric GAD activity assay, as well as an anti-(pSer8 phosphosite-specific) antibody (α-pSer8) to corroborate our LC-MS/MS detection of AtGAD1 phosphorylation. I fully purified AtGAD1 from Pi-sufficient (+Pi) and -Pi cells (+P:GAD1 and -P:GAD1, respectively) to final specific activities of 20 and 32 (μmol GABA produced/min)mg-1, respectively. LC-MS/MS, SDS-PAGE, immunoblotting, and analytical gel-filtration indicated that both final preparations exist as a homohexamer composed of identical 57 kDa AtGAD1 subunits. The 60% higher specific activity of purified -P:GAD1 relative to +P:GAD1 correlated with their differential phosphorylation as detected by LC-MS/MS and α-pSer8 immunoblotting, wherein -P:GAD1 was more highly phosphorylated at Ser4, Ser10, and Ser13, but was hypophosphorylated at Ser8 compared to +P:GAD1. Imaging fluorescent-protein tagged AtGAD1 in Arabidopsis suspension cells, as well as microsomal fractionation and immunoblotting, indicated that GAD’s cytosolic localization was unaffected by changes in nutritional Pi status. Collectively, my data suggest that Pi starvation increases the specific activity of GAD through differential phosphorylation. This change is expected to lead to greater GABA accumulation or flux through the GABA shunt in -Pi plants. This work adds to the literature showing that the shunt is important during abiotic stress responses and expands the knowledge base for future engineering of improved Pi-use efficiency in crops.

abstract: M.Sc.


title: Towards a Theory of Ambient Capitalism: An Inquiry into How Data Creates ValueTowards a Theory of Ambient Capitalism: An Inquiry into How Data Creates Value

contributor:
Murakami Wood, David
Sociology

subject:
Artificial Intelligence
Surveillance Capitalism
Data Economies
AI-First
Google
Ambient Computing

abstract: By asking foundational questions about data, specifically how it creates value in the market economy and the form in which it is traded in the market economy, this text constructs a new, more theoretical model to understand how data and the economy interact. Specifically, I position data as an inherent product of surveillance, resulting in a unique co-creation / co-ownership conundrum that must be resolved by legal mediators for data to become an economic instrument. By applying this model to prevalent theories of data accumulation and exploitation, I develop critiques and potential solutions to the issues created by the current theoretical paradigms of data accumulation presented by theorists such as Zuboff (2015) Fuches (2010, 2019), and Sadowski (2020). Further, using my new understanding of how data functions in the market economy, I further critique Zuboff's surveillance capitalism model, while developing a new theory of the dominant model of data accumulation which I refer to as ‘ambient capitalism’.

abstract: M.A.


title: Racializing Sexual Response: The Role of Identification and Racial Attitudes on Black and White Women’s Responses to Race Congruent and Incongruent Sexual Stimuli

contributor:
Chivers, Meredith
Psychology

rights: Attribution-NonCommercial-NoDerivs 3.0 United States

subject:
Race
Identification
Sexual response
Sexual arousal
Attractiveness
Affect
Racial attitudes

abstract: Identification, or taking the actor’s perspective in a sexual film, is a strong predictor of women’s self-reported sexual arousal, and similarity between the viewer and actors in a film, such as similarity in race, is believed to increase identification. Previous research suggests that race may be a relevant stimulus cue modulating women’s responses to sexual stimuli, including sexual arousal, affect, and appraisals of actor’s attractiveness. Associations between race and sexual, affective, and appraisal responses may be explained by women’s identification with sexual stimuli. If similarity between the viewer and actors in sexual films increases identification, and identification augments women’s sexual response, then women should identify more with race-congruent, compared to race incongruent sexual stimuli (i.e., stimuli depicting actors of the same, or a different race than the viewer, respectively), and in turn, report greater sexual, affective, and appraisal responses to sexual stimuli. As women view race-congruent and incongruent sexual films, another question of interest is whether their sexual responses are influenced by their racial attitudes. The current study examined Black and white women’s self-reported sexual arousal, affect, and appraisal of actors’ attractiveness in response to race congruent and incongruent sexual stimuli, and explored if the relationship between race congruence and women’s responses are mediated by identification, and moderated by women’s racial attitudes. Race congruence was found to be a positive predictor of self-reported sexual arousal, appraisal of the male actors’ attractiveness, and positive affect, but not negative affect. Identification with sexual stimuli mediated sexual, affective, and appraisal responses only for white women, and all women’s appraisals of actors’ attractiveness were moderated by their implicit racial attitudes. Black and white women’s responses were moderated indirectly by explicit racial attitudes through identification. The current study contributes to growing research on race and sexual response and the effects of identification and racial attitudes in the sexual response process. Implications and future directions are discussed.

abstract: M.Sc.


title: Lensed and Reconfigurable Antennas for Passive Beam Forming and Beam Steering

contributor:
Saavedra, Carlos E.
Electrical and Computer Engineering

subject:
3D Printing
Lensed Antenna
Microwave Fluidics
Wideband Antennas
Waveguide

abstract:
Wideband antennas are a crucial part of advanced wireless communications systems. When designing wideband antenna, is it imperative to be able to augment an antenna’s performance to meet a desired outcome, be it beam-steering, gain enhancement, or side lobe level (SLL) reduction. All these aspects can be accomplished by either manipulating time-delay in the feed of an array, or in the antenna’s radiation path by adding a dielectric lens to achieve the desired performance.

This thesis describes the design, simulation, prototyping and measurement of wideband structures, that use dielectric fluids and 3D printed lenses to manipulate the time-delay of the propagating waves for beam steering or beam forming.

Fluidically reconfigurable antennas were designed to give a reconfigurable antenna array and lensed antenna. The phased antenna array used water in substrate integrated channels to provide up to 90° of beam-steering and covered a bandwidth of 3 GHz to 10 GHz. Second, two reconfigurable lensed Vivaldi antennas used a dielectric lens that was loaded with ethyl acetate to show up to 30° of beam-steering across a bandwidth of 20 GHz to 40 GHz by varying the propagation velocity through the lens.

Additive manufacturing was used to produce dielectric lenses that contained difficult to machine geometries. An 18 GHz to 28 GHz 3D printed gradient index
(GRIN) lens mimicked the delay of a Luneburg lens with a 2D permittivity gradient and provided a 5 dB increase in gain over the base horn. Moving a dielectric
cylinder on the inner surface of this lens demonstrated the possibility of passive axial beam-stabilization. Next, an externally metallized conical GRIN lens was printed in the shape of a conical horn that improved the E-plane SLLs compared to a horn by 15 dB from 8.2 GHz to 12.4 GHz. Finally, a 75 GHz to 110 GHz lens was printed that provided a peak gain of 19.5 dBi and reduced the E-plane SLLs compared to a 24 dBi WR-10 standard gain horn. Further SLL reduction was observed by painting the lens support structure with an electromagnetic shielding paint.

abstract: PhD


title: The Shelter of Prophets: A journey within autonomous migration networks

contributor:
Aiken, Sharry
Naaman, Dorit
Cultural Studies

subject:
Autonomy of Migration
Édouard Glissant
Carceral State
poetry
cross-border solidarity
borderlands
autoethnographic fiction
cultural probes

abstract: This MA thesis is a creative and poetic examination of everyday relationships and moments of cross-border solidarity taking place within informal autonomous mobility networks. It argues that in the connections and habits developed and nurtured through everyday moments of solidarity between individuals in borderlands reside a transformative potential for alternative possibilities of being in the world. Informed by interdisciplinary scholarship, including theories of the Autonomy of Migration, the Carceral State, and Édouard Glissant’s pensée du tremblement, I developed a research project based on collaborative autoethnographic (non)fiction and arts-based methodologies. For this project, I exchanged a series of three letters with each of seven participants, who all had significant experiences of cross-border solidarities from vastly different perspectives. Each letter was prompted by creative exercises (cultural probes) designed in a story-making structure to support a safe exploration of life experiences through the use of symbols and metaphors. The images, stories, reflections, and experiences that emerged from this epistolary process were then translated and layered together in order to create the first sections of a hybrid (non)fiction creative text called The Shelter of Prophets. This thesis includes the critical framework which informed the project, a detailed survey of the methodology, and the manuscript of the first sections of The Shelter of Prophets. This manuscript will transport the readers in a journey through a collection of borderland experiences, with the hopes to breach fixed binary thinking, expand social and geographical imaginations, and nurture a more complex and intimate understanding of lives in borderlands.

abstract: M.A.


title: Investigating the Effect of Anxiety on Test Takers’ Performance on a Large-scale High-stakes Computer-based English Listening and Speaking Test

contributor:
Chahine, Saad
Education

subject:
English listening and speaking test
test anxiety
foreign language anxiety
test performance

abstract:
Previous research have suggested that anxiety may affect test takers’ performance on high-stakes tests, such as the National College Entrance Examination (Guangdong) Computer-based English Listening and Speaking Test (the CELST). The CELST test takers can potentially experience three types of anxiety, namely cognitive test anxiety (CTA), foreign language listening anxiety (FLLA) and foreign language speaking anxiety (FLSA). Despite the high-stakes impacts the CELST has on millions of test takers’ future, scarce research has specifically investigated the effect of anxiety on test takers performance and the source of anxiety from the CELST test takers’ perspectives. Therefore. the present study aimed to investigate how CTA, FLLA and FLSA affect CELST test performance.

Quantitative data were collected by administering questionnaires to 585 CELST test takers. Qualitative data were collected by individual semi-structured interviews with twelve test takers. The quantitative analysis showed that: (1) most test takers experienced a moderate degree of CTA, cognitive dimension of FLLA and FLSA; (2) females had a significantly higher level of CTA, cognitive dimensions of FLLA and FLSA than males. (3) self-perceived English competence did impact test takers’ CTA, FLLA and FLSA; (4) the frequency of language use negatively correlated with CTA, FLLA and FLSA; (5) CTA, behavioral dimension of FLSA negatively predicted the CELST scores while the somatic dimension of FLSA positively predicted the CELST scores.

Second, the qualitative analysis confirmed the existence and interference of CTA, FLLA and FLSA among CELST test takers. Besides, the results revealed reasons that lead to anxiety in the CELST, and identified helpful strategies to alleviate anxiety from the test takers’ perspectives.

The findings of the present study have important implications. Theoretically, the study bridged the gap by deepening the understanding of how CTA, FLLA and FLSA affect test takers’ performance in high-stakes foreign language tests. Practically, the findings provide valuable references for the CELST test developers to design test tasks that consider the effect of anxiety such that the CELST can elicit test takers’ best performance. Besides, the findings also provide insights for foreign language teachers to alleviate their students’ anxiety so that students can better perform during the CELST.

abstract: M.Ed.


title: Three Essays on Optimal Decisions under Uncertainties or in the Presence of Strategic Customers

contributor:
Wang, Jue
Business

subject:
Subscription Pricing
Optimal Control
Presence Monitoring
Endangered Species Monitoring
Strategic Customers
Discrete Choice Theory
Decision Analysis
POMDP

abstract:
Three essays on decision-making form this thesis under uncertainties or in the presence of strategic customers.

In the first essay, we studied subscription pricing. Subscriptions are agreements between customers and a company that commits to deliver a product or provide a service. We present a continuous-time dynamic pricing model for a monopolist offering a fixed-term subscription contract, without per-use charges and access limits, to strategic customers whose utility is affected by the number of subscribers. We formulate the monopolist’s problem in terms of optimal control, derive its optimality conditions, and study the structure of the stationary optimal solution. We study the transient and steady states of the problem and show that the firm can capitalize on the strategic behavior of customers. We also observe that the firm is better off not offering subscriptions for myopic customers or customers with a low evaluation of the service. Finally, we demonstrate the robustness of the optimal pricing results in a setting in which we relax significant assumptions.

The second essay considers the joint monitoring and learning of a partially observable dynamic system in which all parameters are unknown. This problem is motivated by the monitoring of cryptic threatened species. The objective is to detect a change in the hidden state while simultaneously learning about the system dynamics and observability. We formulate the problem in the framework of Bayes-adaptive partially observable Markov decision processes (Bayes-adaptive POMDP). A distinguishing feature is that decisions are made under the coupling of state uncertainty, parameter uncertainty, and state dynamics. We identify a low-dimensional sufficient statistic and reformulate the dynamic program in three dimensions. We fully characterize the optimal policy structure. The advantages of the monitoring-while-learning strategy are demonstrated with a case study on the Sumatran tiger conservation in Indonesia.

The third essay investigates a dynamic pricing problem in a stochastic setting and proves that the scaled version of the problem has a fluid limit. The deterministic problem has continuous variables and equations. The optimal control tool is a perfect method to analyze similar continuous-time problems, and it delivers results that are not available in a stochastic setting efficiently.

abstract: PhD


title: Symptom prevalence, healthcare experiences, and psychosocial predictors of symptoms and wellbeing in individuals with persistent genital arousal disorder/genito-pelvic dysesthesia (PGAD/GPD)

contributor:
Pukall, Caroline
Psychology

subject:
Persistent genital arousal disorder
Genito-pelvic dysesthesia
Healthcare access
Fear avoidance model
Prevalence
Psychosocial mechanisms
Sexual health

abstract: Sexual wellbeing is integral to quality of life. Although research and clinical attention has been dedicated to conditions of low genital arousal (e.g., erectile dysfunction, sexual interest and arousal disorder), little is known about disorders of high or unwanted arousal. Persistent Genital Arousal Disorder/Genito-Pelvic Dysesthesia (PGAD/GPD) is a condition characterized by unwanted and persistent sensations of genital arousal that occur in the absence of corresponding subjective sexual arousal or desire. This program of research aimed to examine how common PGAD/GPD symptoms are, as well as factors that influence PGAD/GPD symptoms and psychosocial wellbeing. First, prevalence estimates of PGAD/GPD were undertaken in two North American samples: Canadian undergraduate students and adults in the United States (Chapter 2). The results suggest that PGAD/GPD affects up to 4.3% of individuals and is more common than initially believed. Given the similarities between PGAD/GPD and genito-pelvic pain, the second study (Chapter 3) applied the Fear Avoidance Model of chronic pain to individuals with PGAD/GPD to identify cognitive and behavioural predictors of psychosocial and functional outcomes. Symptom catastrophizing, fear of symptoms, avoidance of symptoms, and hypervigilance to symptoms were associated with greater depression symptoms and poorer functional outcomes. Serial parallel mediation models indicated a significant relationship between PGAD/GPD symptom intensity and psychosocial and functional outcomes through the fear-avoidance variables. The final study (Chapter 4) examined the associations among healthcare experiences (HC), PGAD/GPD symptoms, and psychosocial outcomes, as well as barriers to care and associated costs. Results indicated that most participants waited at least 6 months before approaching a HC provider or had never approached a HC provider about their symptoms. The most frequently reported barrier to HC was HC provider lack of knowledge about PGAD/GPD, and costs associated with HC were high. Increased comfort communicating with one’s HC providers also significantly predicted lower depression and anxiety symptoms. Collectively, the results of this research program highlight that PGAD/GPD affects individuals of all genders and may occur at a higher prevalence than initially assumed. The findings also support the incorporation of cognitive-behavioural interventions for PGAD/GPD as well as the importance of reducing HC barriers to promote treatment accessibility.

abstract: PhD


title: Exploring Characteristics of Patients with Acute Low Back Pain in Ontario Primary Care Settings

contributor:
Norman, Kathleen
Rehabilitation Science

subject:
Low back pain
Primary health care
Sociodemographic factors
Physiotherapist
Chiropractor
Family physician
Spinal imaging

abstract:
Background: Low back pain (LBP) is a common and disabling condition. It impacts the individual, the community and the healthcare system. Patients with LBP are primarily managed in ambulatory settings such as primary care. Common care providers for patients with LBP include family physicians, physiotherapists and chiropractors. The management of patients with LBP is often not aligned with the evidence-based recommendations of clinical practice guidelines. To improve management practices, a detailed understanding of the health condition, including patient characteristics, is important. There is a lack of recent knowledge about the characteristics of patients with acute LBP in primary care in Ontario.
Objective: To describe characteristics of patients with acute LBP in primary care in Ontario, their beliefs about imaging for LBP, and the differences in these characteristics among patients recruited by different practitioners.
Methods: A descriptive observational study was completed as part of a longitudinal cohort study. Registered practitioners from seven geographical regions across Ontario were invited to participate. Practitioners then invited consecutive patients with acute LBP to participate, including completion of a questionnaire completed directly after their initial consultation. The questionnaire included questions relating to their current episode of LBP, sociodemographic information, general health information, and beliefs about LBP.
Results: In total, 13 family physicians, 33 physiotherapists and 27 chiropractors recruited a total of 445 patients to participate. The mean age of patient participants was 46 years and 48% were female. Patients recruited by chiropractors were younger, more had full time employment and were more confident that their pain would be completely gone or much better in 3 months. Older age, higher pain self-efficacy, and higher markers of psychological distress were associated with the agreement that everyone with LBP should have imaging.
Conclusion: There were differences in sociodemographic and pain characteristics among patients who utilized different practitioners, most notable between patients recruited by chiropractors compared to patients recruited by family physicians and physiotherapists. Patient characteristics may influence patients’ beliefs about imaging for LBP. These are key areas for future research and provide a foundation for improving the management of patients with acute LBP in Ontario primary care.

abstract: M.Sc.


title: Bucolic Irony: A Close Reading of Theocritus Idyll One

contributor:
Griffith, R. Drew
Classics

subject:
Theocritus
Bucolic
Pastoral Poetry
Greek poetry
Poetry
Bucolic Poetry
ancient literature
Classical literature

abstract:
Irony, like many abstract Greek nouns, is difficult to pin down to a single definition. Through his sonorous hexameters, Theocritus immediately recalls the Greek oral poetic tradition. In addition to archaic epic traditions, Theocritus incorporates the recent trends of urban poetry, coming mostly out of Alexandria, to aid in his initiation of a “faux” tradition. The terms bucolic and pastoral do not seem to be synonyms, translated from Greek (βουκολικός) into Latin (pastoralis). What it is exactly Theocritus initiated can be explored through a careful analysis of the surfeit of traditions present in his poetry. The result of this analysis has yielded an understanding of Idyll One that, due to the programmatic nature of that poem, can serve as a starting point for future research into Theocritus and ancient pastoral or bucolic poetry.
In Idyll One, Thyrsis and the goatherd seem to abide by a set of rules that gives the lines a palpable irony: it is as if two competing Homeric singers suddenly started singing about the countryside and Pan as a way to compete and argue contemporary poetics. The weaving of traditions, in addition to multiple opportunities for simultaneously complex and simple interpretations, initiates the phenomenon of bucolic irony; this phenomenon both unites the Greek bucolicists and differentiates them from later pastoralists. The approach to irony offered is based largely on Aristotle, but also a modern theory of humour, taking “irony” to mean, most basically, “a misrepresentation of understanding”. Through the evolution of ancient conceptions surrounding both the words βουκολέω and εἴρων, the term bucolic irony is outlined in the first two chapters, followed by four chapters dedicated to a close reading of Idyll One.

abstract: M.A.


title: Harnessing Digital Technologies for Entrepreneurial Innovation

subject:
digital entrepreneurship
digital technologies
digital capabilities
startups
business incubators
university incubators
entrepreneurial innovation

abstract:
This thesis, organized in a 3-paper format, explores the potential of digital technologies to support entrepreneurial innovation using a capability-based perspective. The fast emergence of powerful, readily accessible, and affordable new technologies has transformed the processes and outcomes of entrepreneurial innovation. Both startups and business incubators that support startups, as a result, require an up-to-date and nuanced understanding of how digital technologies can be leveraged to create business value in their respective contexts.
In the first paper, a multilevel framework is inductively developed to explain how digitally-enabled influential factors at the ecosystem level shape innovation environments through business incubators; how startups carry out digitally-enabled entrepreneurial actions; and how business incubators and startups jointly form digitally-enabled intra-incubator action patterns to co-create innovation outcomes at the ecosystem level. Findings of this study confirm the saliency of digital enablement at all three analytical levels (i.e., entrepreneurial ecosystems, business incubators, and startups) and throughout the innovation processes.
The second paper takes a mixed-method approach to explore the value of digital capabilities to startups. Using case data collected from 65 Canadian startups, this study inductively identifies four types of digital capabilities that are commonly developed and used by early-phase startups: digital platform capability, digital infrastructure capability, digital adaptation capability, and digital knowledge capability. Drawing on the insights derived, fuzzy-set qualitative comparative analysis was conducted to examine high-performing digital capability configurations for startups at the business validation and transition stages. The results show that the high-performing configurations differ from validation to transition, and that digital startups and their less-digital counterparts rely on different digital capability configurations to succeed.
The third paper investigates further a key finding from the first paper – that is, today’s business incubators are being transformed from siloed support infrastructure to active resource orchestrators in entrepreneurial ecosystems. Specifically, this study examines the influence of dynamic digital capabilities on both the agility and performance of publicly-funded business incubators. The research framework is tested and supported using survey data. It is found that resource orchestration capabilities fully mediate the impact of dynamic digital capabilities on incubator performance, and partially mediate the latter’s impact on incubator agility.

abstract: PhD


title: A Critical Laboratory Investigation of Multi-Stage Direct Shear Testing Procedures on Rock Joints Using Synthetic Replica Specimens

contributor: Geological Sciences and Geological Engineering

subject:
Rock Mechanics
Laboratory Direct Shear Testing
Synthetic Specimens
Rock Joint
Multi-Stage Direct Shear Testing

abstract:
Direct shear testing is a common laboratory method used to define the geomechanical parameters of rock fractures for numerical inputs and rock engineering design. Of the standardized procedures, multi-stage direct shear testing is a controversial practice of repeatedly shearing the same rock joint specimen under increasing normal stresses to define its failure envelope. The limitations associated with multi-stage direct shear testing have been addressed in previous research and demonstrate that additional stages will reduce the measured peak shear strengths and impact the interpreted linear Mohr-Coulomb shear strength parameters.
	This research presents the results from 50 single stage, 8 multi-stage (with repositioning), and 8 limited displacement multi-stage direct shear tests completed on synthetic specimens. To create the synthetic specimens, a rigorous workflow was developed to transform rock joint specimens into synthetic replica specimens cast in cement grout using 3-dimensional Structure from Motion (SfM) photogrammetry and 3D printing technologies. In this research, four unique synthetic sample designs were generated using two parent rocks and two water: cement grout mixture ratios. Four unique sample designs enabled the author to observe how isolating a change in the joint roughness coefficient and/or a change in the joint compressive strength impacts the measured geomechanical parameters. Furthermore, using the single stage results as a baseline for comparison, the impact multi-stage direct shear testing procedures have on the measured geomechanical parameters are evaluated.
	The results presented in this research demonstrate that surface roughness characterization and its contribution to shear strength is more complex than currently practiced. The current practice of generalizing a rock joint specimen’s roughness based on the intensity in the relief of its asperities in cross-section can be misleading. Rather, joint roughness should consider the 3-dimensional geometry and dip angle of the asperities dipping subparallel to the shear direction. Furthermore, the results demonstrate that multi-stage direct shear testing procedures significantly impact the measured geomechanical parameters when compared to single stage test results. Finally, this research demonstrates that the residual joint friction angle of the tested synthetic cement grout specimens is not a material constant and has a reliance on the specimen’s topology and shear failure mechanisms.

abstract: M.A.Sc.


title: Es-PACES on Mexican Campuses: Cultural Adaptation of the Physical Activity Campus Environmental Supports Audit

contributor:
Lévesque, Lucie
Kinesiology and Health Studies

subject:
physical activity
built environment
recreation
cultural adaptation
university
campus
audit

abstract: Introduction: Increasing physical activity is a global priority yet most physical activity promotion research comes from high-income countries. Physical activity research is needed in low- and middle-income countries, such as Mexico, to inform culturally relevant physical activity promotion and to achieve Sustainable Development Goals. University campuses are ideal settings for population-level physical activity promotion. The Physical Activity Campus Environmental Supports (PACES) audit by Horacek et al. (2019) has been used to assess the facilities and programs on campuses in the United States. Linguistic, cultural, and contextual differences between campuses in Mexico and the United States may impact the utility of PACES in Mexico. Purpose: To modify PACES to capture the unique physical activity context of Mexican campus environments and to obtain preliminary evidence on the physical activity supports at selected University of Guadalajara campuses. Methods: In phase one, PACES was tested on one campus and modified via group discussion to produce a preliminary culturally adapted version: Es-PACES. In phase two, Es-PACES and the Physical Activity Resource Assessment tool (PARA; Lee et al., 2005) were applied to six campuses. The research team discussed further adaptations to Es-PACES. Data Analysis: Interrater reliability was calculated, and descriptive statistics were used to analyze Es-PACES and PARA data. Kruskal-Wallis tests were used to explore PARA audit scores relative to campus population sizes. Group discussion content was analyzed. Results: All original PACES questions were maintained. Some response options were removed, and others added to better reflect unique Mexican campus features. Es-PACES showed excellent interrater reliability. Programs and facilities varied across campuses; there was no difference between PARA scores in relation to campus population size. Six recommendations were made to further adapt Es-PACES. Discussion: Es-PACES is useful for obtaining information on physical activity supports on University of Guadalajara campuses and is complemented by PARA for assessing quality. Es-PACES warrants further adaptations for use on Mexican campuses.

abstract: M.Sc.


title: Genomic evidence of long-term asexuality at the northern range limit of wetland plant, Decodon verticillatus (Lythraceae)

contributor:
Eckert, Christopher
Biology

subject:
Asexual reproduction
Range limits
Transcriptome

abstract: Many plant species shift from sexual to asexual reproduction at geographic range edges, but the impact of asexual reproduction on range expansion is largely unknown. If asexuality allows genotypes well-adapted to range edge conditions to persist long-term without recombination, this may allow plant species to expand beyond their sexual niche (“AEH: asexual expansion hypothesis”). Alternatively, asexual populations could represent short-lived genetic sinks that restrict further range expansion (“ASH: asexual sink hypothesis”). I investigated these hypotheses in the emergent wetland plant, Decodon vertcillatus (Lythraceae), which shifts from sexual to asexual reproduction at its northern range limit. I did a de novo transcriptome assembly and compared SNPs in sexual and asexual populations at and approaching the northern range limit to determine if range-edge, asexual populations show genomic signatures of long-term asexuality consistent with the AEH. Asexual genotypes exhibited higher heterozygosity, fewer unique homozygous SNPs (doubletons), and a breakdown of isolation by distance, supporting the AEH. Asexual genotypes also showed some evidence for an accumulation of deleterious non-synonymous and radical amino-acid altering mutations. In contrast to the AEH, the quantity of unique heterozygous SNPs (singletons) did not differ between sexual and asexual genotypes, and average genetic differentiation was unexpectedly higher among sexual than asexual genotypes. Yet, on the whole, my results support the asexual expansion hypothesis, suggesting that asexual reproduction allowed Decodon verticillatus to expand its range further northward than would have been possible under sexual reproduction alone. Understanding the factors that influence range limits and range expansion is becoming increasingly important to better anticipate the capacity of species to adapt, and potentially shift their ranges in response to anthropogenic environmental changes and prioritize range-edge populations for conservation.

abstract: M.Sc.


title: From Military to Civilian Primary Care: A Study of Veteran Transition

contributor:
Cramm, Heidi
Donnelly, Catherine
Rehabilitation Science

subject:
Military-to-civilian transition
Veteran health
Primary care
Canadian Armed Forces
Qualitative

abstract:
Background: Military-to-civilian transition (MCT) is generally understood as the process of leaving military service and transitioning to civilian life. Each year, approximately 5000 Regular Force Canadian Armed Forces (CAF) members leave the military. During service, CAF members access the military health care system and, after release, must transition to provincial/territorial primary care. Since Veterans experience health problems at greater proportions and use primary care more than the general population, this is an important aspect of MCT. However, no research has investigated Canadian Veterans’ experience of transitioning from the military to the civilian primary care system or how primary care is provided to Veterans.
Objectives: To understand the transition from the military to the civilian primary care system and to understand how interprofessional primary care is provided to Veterans in the civilian system.
Methods: Three studies were conducted to address these objectives. First, a phenomenological analysis of previously collected qualitative data from CAF members with an upcoming release. Second, a phenomenological study conducted with Veterans after release. Third, a single mixed-methods exploratory case study focusing on how team-based primary care is provided to Veterans.
Results: The transition to civilian primary care encompasses anticipation of and preparation for the change in primary care provider (PCP) before the release date, making the leap from military to civilian primary care in the months and years that follow the release date, and eventual landing in the care of a primary care team in the civilian system. Many participants were able to make the transition to civilian primary care with relative ease. However, for those with ongoing health issues requiring consistent access to care, the transition was challenging and had implications for health and well-being. The interprofessional primary care team examined in the case study revealed the importance of Veteran-friendly and culturally competent primary care.
Conclusion: The transition to civilian primary care, like MCT more broadly, is complex and variable; continuous access to primary care throughout the transition is important. More research is needed to better understand this underexplored aspect of MCT to better serve transitioning Veterans in the future.

abstract: PhD


title: Numerical Study of Detonation Propagation in a Nonuniform Hydrogen-Oxygen Layer Bounded by an Inert Gas

contributor:
Ciccarelli, Gabriel
Lau-Chapdelaine, S. She-Ming
Mechanical and Materials Engineering

subject:
Detonations
CFD
Diffuse Layer Detonation
Hydrogen Safety
Rotating Detonation Engines
Gravity Current

abstract:
This numerical study investigates the propagation failure and limits of a detonation through stoichiometric hydrogen-oxygen layer stratified above an inert gas with a diffuse interface at atmospheric pressure. The study simulates previously-conducted experiments where the layer is buoyancy driven. Diffusive gravity current simulations are used to generate the initial conditions. Detonation propagation is modeled by solving the two-dimensional reactive Euler equations for a calorically perfect gas with single-step Arrhenius chemistry. To account for acoustic impedance gradients under the limitations of the perfect gas assumption, the initial temperature is varied throughout the simulated mixture while pressure and density are held true to the physical experiments, where pressure and temperature were uniform. The simulations are validated using the physical stoichiometric hydrogen-oxygen experiments this numerical study strives to replicate. Numerical soot foils are generated from simulations and are compared to the experiment’s.

The study verified Bauwen’s and Dorofeev’s failure criteria for non-uniform reactant mixtures which states a minimum of 5-7 cells are needed for a detonation to sustain itself under the bounds of dλ/dx ≤ 0.1.
Two models are proposed to investigate the failure in the diffuse layer reported in experiments. Both consist of tailoring the activation energy of the mixture spatially based on the inert gas dilution; one accounts for the non uniform temperature within the domain calculated by the numeric code, the other maintains the correct constant volume ignition time.

Re-initiation of the detonation in the diffuse layer was seen through regeneration of triple points that seep into the reactive layer. These triple points that generate new detonation cells are credited to inflection zones that occur in the diffuse layer that develop because of the local increase in detonation strength.

abstract: M.A.Sc.


title: Investigating the therapeutic potential of cannabidiol for Alzheimer’s disease: Using Caenorhabditis elegans that express the amyloid-beta protein

contributor:
Bendena, William
Biology

subject:
C. elegans
Cannabidiol
Alzheimer's disease
Amyloid-beta

abstract: Roughly 55 million people worldwide suffer from dementia, and its prevalence is predicted to increase to about 139 million by 2050. Alzheimer’s disease (AD) is the most common form of dementia, accounting for 60-70% of cases. It is a progressive neurodegenerative disease characterized by various cognitive deficits beyond those associated with ageing. The prevailing hypothesis of AD pathology, the amyloid cascade hypothesis, assumes that the accumulation of the amyloid-beta (Aβ1–42 ) protein is the causative agent. AD has no cure and current treatments provide limited therapeutic benefits. Cannabidiol (CBD) is a cannabinoid derived from Cannabis plants  that has neuroprotective, anti-inflammatory, and antioxidant properties. Research has shown its potential to help decrease Aβ production and protect against Aβ-mediated neurotoxicity in human cells. Further, CBD has been shown to reverse spatial memory deficits and prevent neuroinflammation from Aβ injection in rodent models. However, research on CBD as a treatment for AD is limited and the underlying mechanism is unclear. The model organism, Caenorhabditis elegans, is a well-established tool for studying human neurodegenerative diseases at a molecular level. A strain of C. elegans has been generated to express pan-neuronal Aβ1–42. This Aβ-expressing C. elegans has an age-related onset of dysfunction, including shortened lifespan and decreased locomotion, similar to what is observed in humans with AD. My research investigates the therapeutic potential of CBD and its mechanism in the Aβ-expressing C. elegans. Our findings support CBD as a therapeutic for AD and provide insight to how it is working. Results from our study will help fill the missing link between the effects of CBD on Aβ accumulation in AD and provide information on the role of CBD for AD treatment in humans.

abstract: M.Sc.


title: The Neuromechanical Mechanisms of Exertional Dyspnea Across the Continuum of Chronic Obstructive Pulmonary Disease (COPD) Severity

contributor:
O'Donnell, Denis E.
Neder, J Alberto
Translational Medicine

subject:
COPD
Dyspnea
Respiratory physiology
Clinical physiology
Exercise physiology
Cardiopulmonary exercise testing
Inspiratory neural drive
Gas Exchange
Respiratory mechanics

abstract:
Rationale: Patients with chronic obstructive pulmonary disease (COPD) have burdensome exertional dyspnea (breathlessness) during exercise, which is associated with an elevated inspiratory neural drive (IND). The neurophysiologic mechanisms of dyspnea across the continuum of disease severity remain incompletely understood.
Objectives: The main objectives of this thesis were to 1) determine the contribution of an isolated reduction in the diffusing capacity for carbon monoxide (DLCO) to elevated IND and dyspnea during exercise in mild COPD, and 2) to determine the role of critical inspiratory constraints in elevated IND, neuromechanical dissociation (NMD), and dyspnea intensity and quality during exercise across the continuum of COPD.
General Methods: All studies included resting pulmonary function testing, and cycle cardiopulmonary exercise testing (CPET). During CPET, physiologic parameters including ventilatory requirements, pulmonary gas exchange, breathing pattern, and operating lung volumes, and perceptual parameters of dyspnea intensity and quality, were evaluated. All studies used an esophageal catheter during CPET to measure diaphragm activation as a surrogate of IND.
General Results: 1) Patients with mild COPD and an isolated reduction in DLCO have an elevated IND and dyspnea compared with patients with a preserved DLCO and similar resting lung mechanics. This was associated with reduced ventilatory efficiency (i.e., a high ventilation relative to carbon dioxide production, V̇E¬/V̇CO2). Acute administration of inhaled nitric oxide, a pulmonary vasodilator, reduced physiologic dead space and V̇E¬/V̇CO2, which was associated with reduced IND and dyspnea compared with placebo. 2) IND was progressively elevated from mild to severe COPD, which was associated with earlier attainment of critical inspiratory constraints and NMD, greater dyspnea intensity, a greater frequency of reporting “unsatisfied inspiration”.
Conclusions: This thesis has shown that patients with mild COPD have elevated dyspnea and IND that is associated with a low DLCO¬, independent of the effects of respiratory mechanics. We have also shown that the attainment of critical inspiratory constraints has important implications for neuromechanical dissociation, dyspnea intensity, and quality across the continuum of COPD. The findings of this thesis have added to our understanding of the neurophysiology of dyspnea across the continuum of COPD severity.

abstract: PhD


title: Roadmap to Brownfield Remediation for Urban Agriculture in Kingston, Ontario

subject:
Brownfields
Urban agriculture
Contaminated lands

abstract:
As Canada continues to transition towards deindustrialisation, brownfields have become a problematic by-product that causes environmental and social issues within cities. Brownfields are especially prone to degrade communities in marginalized areas. The goal of this research is to determine the best practices for urban agriculture on brownfield sites in Kingston, Ontario. The City of Kingston currently has a Community Improvement Plan that outlines the policies and procedures in regard to brownfield remediation. Kingston has no urban agriculture on brownfield sites and there are gaps in the policies that guide the city on the most appropriate way to conduct a project like this on contaminated lands. This study was conducted by analyzing Ontario and Kingston government reports to determine the policies that regulate urban agriculture on brownfield sites. Case studies were selected to determine the best practices for urban agriculture in the Canadian context.
The findings demonstrate that urban agriculture on brownfields is an integral component to Kingston Ontario sustainable growth. Whether the property is for mixed use such as housing and agriculture or solely agricultural, it promotes civic engagement and connects the community with the land and ecosystem.


title: Development of Two Novel Families of Platinum(Ii) Coordination Complexes for Nucleic Acid Recognition

contributor:
Petitjean, Anne
Chemistry

subject: Synthesis, Nucleic Acid Recognition, Platinum(II) Complexes, Heterocycles, Guanine Quadruplex

abstract:
Nucleic acids can adopt shapes other than the widely recognized double helix duplex form of DNA. In fact, they can also self-assemble into alternative higher order architectures, such as guanine quadruplexes (G4s). These four stranded assemblies have risen to prominence as promising drug targets as a result of their demonstrated relevance and enrichment in genomic regions involved in cancer, neurodegenerative conditions, bacterial infections, and viral infections. Therefore, targeting G4s using small molecule binders has rapidly grown as a field of research due to the potential therapeutic effect on a range of possible diseases. The overall objective of the MSc research presented herein is to synthesize and characterize novel G4 binders based on a platinum(II) coordination platform with high G4 affinity, with the future goal of assessing their G4-recognition and stabilization abilities.
The first family of novel complexes contains an aromatic platform functionalized with moieties that could potentially improve G4 binding affinity and/or specificity through interactions with loops or grooves. Synthesis of the ligands and complexes is described, as well as any observed luminescent properties. Promisingly, preliminary biophysical information from UV-Vis titrations of two of the synthesized complexes qualitatively demonstrated strong interactions with a G4-forming DNA sequence.
The second family of G4 binders involves tri- and tetradentate ligands and corresponding Pt(II) complexes with controlled sequences of heteroaromatic units that provide the opportunity to explore potential differences in G4 interactions between alternative binder footprints. The investigation of various synthetic methods and challenges overcome are described in the journey to synthesize and characterize the final polydentate complexes.
The two novel families of Pt(II) complexes developed in this thesis will lay the foundation for future biophysical studies with biologically relevant G4 sequences, to evaluate their performance as promising binders for G4 recognition.

abstract: M.Sc.


title: Assessing Soft-Embalmed Cadavers as a Biological Hazard

subject:
Cadaver
Phenol-embalmed
Dissection
Pathogenic activity
Sterilization
Containment Level
Antimicrobial
Biohazard
Soft-embalmed
Health and Safety
Microbiology
Infectious diseases
Anatomy
Organism biology

abstract: At Queen's University Department of Biomedical and Molecular Sciences, as is the case at many Canadian institutions, three primary methods are used to generate three distinct cadaver types for human anatomical education: fresh/frozen, traditional formalin hard-embalmed, and phenol-based soft-embalmed. Each of these techniques has its own merits and restrictions, with phenol-based soft-embalming combining the longevity seen in traditional embalming with the life-like quality characteristic of fresh/frozen tissue. Current environmental health and safety (EHS) restrictions place traditional formalin embalmed cadavers in Containment Level 1 (CL1) laboratories, with both fresh/frozen and phenol-based soft-embalmed cadavers in Containment Level 2 (CL2) laboratories. However, there is a gap in the current literature dictating whether or not phenol-based soft-embalmed cadavers do in fact belong in CL2 laboratories. In this hypothesis-driven report, it was hypothesised that soft-embalmed cadavers are a higher risk biosafety hazard than formalin-embalmed cadavers, thus warranted for designation to CL2 laboratories. After an in-depth analysis of the present literature surrounding the use and properties of phenol-based soft-embalmed cadavers in comparison to traditional formalin hard-embalmed cadavers, it was found that soft-embalmed cadavers do become colonized more readily by micro-organisms, aligning with our hypothesis. To definitively test the hypothesis, a proposed experiment has been suggested and outlined. In the proposed experiment, a variety of indicator species as well as CL2 designated pathogens would be tested for at regular intervals throughout the cadavers’ lifespans.


title: Dynamics of Clonal Hematopoiesis of Indeterminate Potential and Clinical Outcomes Following Chemotherapy in Lymphoma Patients

contributor:
Rauh, Michael
Pathology and Molecular Medicine

subject: Lymphoma treatment

subject: Chemotherapy complications

subject: Personalized cancer treatment

abstract: Clonal hematopoiesis of indeterminate potential (CHIP) is a potentially premalignant condition of aging that arises upon the expansion of somatically mutated hematopoietic stem/progenitor cells in hematological malignancy-free individuals. CHIP can be detected in 10-15% of healthy older patients and can lead to dysfunctional hematopoiesis and dysregulation of immune functions of mature blood cells. In lymphoma patients treated with front-line chemotherapy, CHIP can be detected in 20% of patients. However, this is not routinely considered, nor does it currently alter treatment plans. Rates of various chemotherapy-related complications such as febrile neutropenia, grade 3-4 anemia, leukopenia, and hospital admissions are higher in elderly lymphoma patients. Clinicians remain unsure as to why some older lymphoma patients go through chemotherapy treatment rather uneventfully while others of comparable performance status and comorbidity suffer repeated complications that can necessitate dose reductions/delays. We hypothesized that CHIP may be a risk factor for chemotherapy complications in older lymphoma patients related to the dysfunctional bone marrow and blood cells caused by CHIP. We performed targeted next-generation sequencing for a cohort of older lymphoma patients prior to their commencement of chemotherapy and at three treatment time points. This revealed that the prevalence and variant allele frequency (VAF) of CHIP variants, particularly variants in DNA damage response genes (DDR), increased during chemotherapy treatment. We then compared the CHIP profiles of these patients with clinical records tracking chemotherapy-related complications and found DDR CHIP to be significantly associated with respiratory toxicities. Additionally, univariate analysis showed CHIP to be associated with altered blood cell parameters including hemoglobin, eosinophils, basophils, platelets, red blood cell distribution width (RDW), mean corpuscle volume (MCV), whether RDW or MCV increased during treatment, and the number of MCV increases. Through multivariable analysis, associations between CHIP and number of MCV increases, platelet count, RDW, and whether RDW increased remained significant. We plan to expand this study to a larger cohort, performing further sequencing and clinical analysis. This may provide early insight into which patients might be most at risk for chemotherapy complications and blood count alterations, allowing for the development of personalized treatment plans and the optimization of patient outcomes.

abstract: M.Sc.


title: Simulations and Observations of Galaxies Constrained through Scaling Relations

contributor: Physics, Engineering Physics and Astronomy

subject:
Galaxies
Numerical Simulations
Extragalactic Astrophysics

abstract: Understanding galaxy formation and evolution requires robust comparisons of observations and simulations of galaxies. This thesis contrasts rich observations of galaxies with simulations (hydrodynamical and semi-analytical models, hereafter SAMs1 ) to study structural galaxy scaling relations and star formation quenching. The role of AGN feedback on galaxy quenching is studied for central galaxies at z = 0 through the comparison of 500,000 SDSS galaxies with SAMs (L-GALAXIES and SAGE). We find that galaxy passive fractions measured for observations and the SAGE SAMs correlate with the stellar mass of the bulge component; for the L-GALAXIES SAMs, passive fractions correlate with halo and black hole mass. Overall, SAMs do not reproduce the observed passive fractions as they fail to model the coupling between the heating and cooling of gas due to AGN feedback. We also extract and compile a multi-band photometric and environmental catalogue for ∼8000 MaNGA galaxies. The deep surface brightness profiles are extracted in a non-parametric fashion from the automated software AUTOPROF and reach depths of 28.5 g − mag arcsec−2 , 27.8 r − mag arcsec−2 and 26.7 z − mag arcsec−2 . Non-parametric surface brightness profiles are shown to be more robust and reproducible relative to model (S´ersic or S´ersic + Exponential) dependent surface brightness profiles. As a complement to the photometric catalog, 1All acronyms are defined in the glossary. i rotation curves and a dynamical catalogue are also presented and used to construct multiple observed scaling relations. The latter are compared to similar scaling relations from the high-resolution NIHAO zoom-in simulations. NIHAO galaxies broadly agree with 12 observed scaling relations which the exception of those involved central surface densities (measured via Σ1). Finally, we have also compared simulated field and LG dwarf galaxies to highlight similarities and differences. Present-day LG dwarfs show similar stellar properties to field galaxies but very different gas properties, particularly hot gas metallicities. The difference in gas metal content is the result of interactions amongst LG dwarfs which live in a higher density environment than the field. The high quality data reductions presented in this thesis will lead to further refinement of the cosmological simulations.

abstract: PhD


title: Definition of Geological Domains with an Ensemble Implementation of Support Vector Classification

contributor:
Ortiz, Julian
Mining Engineering

subject:
Geostatistics
Geological modeling
Machine learning
Ensemble learning

abstract:
Building a resource model can be a challenging process because of the complex nature of geology. Employing limited information to build the resource model inevitably gives rise to uncertainties, and therefore uncertainty is an important phenomenon that needs to be taken into account while building the model. In fact, quantifying the uncertainties can be a significant advantage for the evaluation of mineral resources. Uncertainties can be quantified by traditional approaches, such as geostatistical simulation methods. While traditional approaches generally focus directly on domains to build geological models, today huge geochemical datasets obtained during exploration campaigns are seen as an opportunity to better evaluate the geological models. In this context, machine learning algorithms stand as a strong alternative to traditional approaches (explicit or implicit modeling, or geostatistical techniques), because they can easily incorporate large and multivariate datasets to reach consistent and semi-autonomous results.
This study proposes an ensemble learning approach to define geological domains and their inherent uncertainty. The study adopts an unsupervised binary clustering method to label the domains of a multivariate geochemical dataset, and the information obtained by this unsupervised method is used to inform a supervised learning algorithm, which is Support Vector Classification. The supervised learning step is applied to assign domaining in locations of a gridded model. The unsupervised and supervised learning steps are repeated with subsets of geochemical variables and with subsets of training samples to realize an Ensemble model. These models are combined to define a strong model, and the uncertainty can be incorporated with the model. Finally, a hierarchical application is applied on the results to build multiple domains. We demonstrate the proposed workflow with an application to a real database from a porphyry copper deposit. The workflow was capable to build a robust model with high accuracy and with well-defined, curvy boundaries.

abstract: M.A.Sc.


title: Exploring the Impact of Two Types of Meditation for Individuals High in Attachment Anxiety Experiencing Conflict in Romantic Relationships

contributor:
MacDonald, Tara
Psychology

subject:
Attachment Anxiety
Mindfulness
Romantic Relationships
Romantic Conflict

abstract: Individuals high in attachment anxiety fear rejection in close relationships. Limited research has examined tools to help individuals high in attachment anxiety cope with stress. In a previous experiment I found that mindfulness exacerbated stress reactions for individuals high in attachment anxiety primed with rejection. Specifically, higher levels of mindfulness were associated with increased negative reactions to an imagined relationship threat for individuals high in attachment anxiety. I theorized that different types of mindfulness may be associated with different experimental outcomes. I hypothesized that an external focus of meditation (i.e., grounding to sensory aspects of one’s environment) may be more helpful for individuals high in attachment anxiety experiencing relationship stress, relative to an internal focus of meditation (i.e., paying attention to one’s body and breath). Neutral aspects of one’s environment may be a less threatening target of attention, allowing high-attachment anxiety individuals to reap the benefits of mindfulness. I conducted two studies to examine this hypothesis: a laboratory experiment, and a two-week diary study. Both studies included an internally-focused meditation condition, an externally-focused meditation condition, and a control audio condition. After two weeks of daily meditation, individuals high in attachment anxiety reported similar levels of mindfulness to individuals low in attachment anxiety. Thus, the intervention removed the typical association between high attachment anxiety and lower levels of mindfulness. With regards to relationship outcomes, across both studies the meditation conditions were associated with exacerbation effects for individuals high in attachment anxiety (i.e., more intense stress reactions). I discuss implications of these findings, as well as the importance of examining how personality traits moderate the effectiveness of interventions in the context of stress.

abstract: PhD


title: Acoustic Telemetry Provides New Insights into the Ecology of Smallmouth Bass in Eastern Lake Ontario

contributor:
Tufts, Bruce
Biology

subject:
Smallmouth Bass
Ecology
Telemetry
Behaviour

abstract: Smallmouth Bass (Micropterus dolomieu) are a top predator native to the Laurentian Great Lakes, with a wide distribution in North America. Our understanding of Smallmouth Bass ecology is extensive, although primarily based on research from smaller inland lakes, rivers, and reservoirs. In Lake Ontario, there is an urgent need for additional research on this species due to the apparent declines and invasive species-mediated changes in the Smallmouth Bass population in recent years, documented by provincial and state agencies. A better understanding of the status of Smallmouth Bass populations is especially important in the Southern Great Lakes since pressure from recreational anglers also appears to be increasing. The objective of the present study was to examine whether a novel acoustic telemetry approach could be used to obtain information on the spatial ecology of Smallmouth Bass in the eastern basin of Lake Ontario. Near continuous detections were recorded for eleven Smallmouth Bass, expanding the practical toolbox of passive acoustic telemetry in large lake ecosystems. The present study also provides evidence that this species exhibits local residency to a greater degree than previously understood. Smallmouth Bass depth use and activity rate varied seasonally, with winter characterized by deeper depths and lower vertical and horizontal activity relative to the summer period. Home range size decreased during the overwintering period, with simultaneous shifts in home range centrality towards deeper bathymetric features surrounding the study site. The use of a small-scale passive array to study a nearshore predator in the Great Lakes is a novel approach that has improved our understanding of Smallmouth Bass ecology. The findings of this research also have important implications for assessing, managing and conserving the Smallmouth Bass populations in the Great Lakes.

abstract: M.Sc.


title: Spatial Declustering of Zircon Data Indicate Rapid Archean Crustal Growth and Neoproterozoic Plate Tectonic Equilibrium

subject:
Continental growth
Crustal evolution
Hf-isotopes
Detrital zircon
Declustering
Tectonic equilibrium

abstract: The geochemical information stored in mineral zircon makes it widely used to document the formation and evolution of the continental crust. The physiochemical resilience of zircon enables precise isotopic dating even in scenarios where the zircon has experienced an array of multi-cycle geologic processes. The isotope information can be used to model the balance between the formation of new crust and the reworking of old crust throughout Earth's history. Previous models of continental crust growth relied on radiogenic isotope pairs, such as 176Lu/176Hf, but incorrectly formulated the spatiotemporal bias. This thesis presents a simple approach for spatiotemporal cluster correction using 19806 integrated U–Pb and Hf-isotope analyses of global detrital zircon compilation. The declustering algorithm is used to examine the representativeness of existing models and improve previous estimates of crustal evolution on regional and global scales. The new declustered modelling suggests faster continental growth during the Archean Eon and very little continental growth since the mid-Proterozoic. At around 1.0 to 0.7 Ga, the marked little to no net continental growth may be highlighted as the transition to mature modern-style tectonics. The distribution of crustal formation age estimated in this thesis serves as the lower limit to the true crustal growth, and the role of preservation bias and the degree of crustal destruction remains unknown.

abstract: M.Sc.


title: Examining the Effects of Individually Ventilated Cages on Rat Defensive Behaviour

contributor:
Menard, Janet
Psychology

subject:
Defensive Behaviours
Social Buffering
Animal Models of Anxiety
Individually Ventilated Cage
Social Isolation

abstract: Historically, laboratory rodents were housed in conventional open-topped cages (OTCs), which are held under ambient ventilation and the intracage environment is directly influenced by the environment of the colony room. Many research facilities now replace these OTCs with individually ventilated cages (IVCs), which are hermetically sealed chambers designed to protect both laboratory rodents and experimenters. Evidence suggests IVCs may increase rodent defensive behaviours, potentially because their hermetic seal prevents the flow of olfactory and auditory information between cages. While social housing is well-known to buffer rodent stress, it is unclear if these protective effects will endure in an IVC system. I hypothesized that IVCs would increase defensive behaviour relative to OTCs. I further hypothesized that single-housed rats would be more behaviourally defensive compared to pair-housed rats due to the protective effects of social buffering, but only in the OTC condition. Forty-eight male rats were randomly assigned to OTC or IVC housing, either singly or in same-sex pairs. After four weeks of acclimating, all rats underwent testing in the Elevated Plus-Maze (EPM) and the Shock-Probe Burying Test (SPBT), followed by the removal and weighing of the adrenal glands. There was evidence of social buffering in the EPM, as single-housed rats had lower levels of open arm activity than pair-housed rats, suggesting more behavioural defensiveness. Further, pair-housed rats maintained in OTCs completed fewer protected stretch attend postures than pair-housed rats in IVCs, suggesting lower levels of behavioural defensiveness in response to a potential threat. In the SPBT, there were no differences in defensive burying between any experimental conditions. However, there was further evidence of social buffering as singly housed rats averaged significantly fewer stretch attend postures than pair-housed rats, suggesting an increase in anxiety-like behaviour in response to a localizable threat. Surprisingly, these behavioural effects were not supported with physiological data, as there were no effects of cage type or housing on adrenal gland weight. Overall, these findings provide evidence that IVCs influence rats’ defensive behaviours, that social buffering does have protective effects in IVCs, and that further research is needed to determine how IVCs impact animal behaviour and welfare.

abstract: M.Sc.


title: Distributed Newton-Seeking for Resource Allocation

contributor:
Guay, Martin
Chemical Engineering

subject:
Distributed Optimization
Resource Allocation
Consensus
Extremum Seeking Control

abstract:
Real-time optimization (RTO) is a category of closed-loop process control techniques that is focused on the improvement of process performance. To develop effective strategies, models of the systems are usually required. To circumvent this issue, model-free techniques such as Extremum-seeking control (ESC) have been developed that can accomplish the RTO task in the absence of any knowledge of the process dynamics and of the objective function. Using this optimization methodology, this thesis develops an approach to solve resource allocation problems in a fully distributed fashion where the separable
cost function is unknown with dynamics in discrete time. To accomplish this, we utilize a distributed extremum-seeking scheme that estimates the cost function’s gradient and Hessian to implement Newton step dynamics. It is shown that the extremum-seeking approach yields asymptotic convergence of the primal and dual problem to a neighbourhood of the optimal values.
We propose two strategies to solve finite resource allocation problems. The first strategy tackles the globally convex cost function case. It requires a simultaneous solution of the primal problem and its associated dual problem. The second
strategy utilizes a more general approach with an pseudo-Hessian for the solution of local saddle point problems. It allows a full separation of the primal and dual dynamics. Two simulation case studies are performed for each strategy. The first case is
a small-scale 3-agent problem highlighting the differences between the strategies. The second is a 25-agent problem that mimics more realistic scenarios. Finally, a stability analysis is conducted to characterize the transient performance of the
two strategies.

abstract: M.A.Sc.


title: Students at Work: Care work, Neoliberalism, and Survival in Precarious Times

contributor:
Hall, Rebecca
Cultural Studies

subject:
care work
neoliberalism
social reproduction
social reproduction theory
feminist theory
university students
Queen's University
feminist methodology
studying up
time use
politics of time

abstract: This research project examines the time use of undergraduate students at Queen’s University, a public university located on Anishinaabe and Haudenosaunee land in Ontario, Canada, with a focus on how much time they devote to care work. I argue that the university has become akin to a workplace, and students have accordingly become workers. This research is rooted in feminism theory and methodology, particularly intersectional feminist theory and social reproduction theory. I utilize time-use surveys and interviews to examine the potentially gendered and racialized dynamics of care work among students. I employ the feminist analytical approach of “studying up” by examining structural dynamics through the perspective of the everyday. I thus connect my findings to neoliberal theory and critique, its creation of so-called “life workers,” and the internalization of neoliberal discipline. I also discuss neoliberalism’s and the pandemic’s impact on care work and student time use overall. Finally, I use my interview findings to discuss structural issues at Queen’s University, and offer policy recommendations. I ultimately argue for the importance of centering care in a precarious world.

abstract: M.A.


title: Tail Asymptotics for the Limiting Distribution of Theta Sums

contributor:
Cellarosi, Francesco
Mathematics and Statistics

subject:
Probability Theory
Number Theory
Dynamical Systems

abstract:
We define theta sums to be exponential sums of the form S_{N}(x; \alpha, \beta) := \sum_{n =1}^{N}  e((\tfrac{1}{2} n^2 + \beta n)x + \alpha n), where e(z) = e^{2 \pi i z}. If \alpha and \beta are fixed rational numbers, and x is chosen randomly from the unit interval, we use homogeneous dynamics to show that \tfrac{1}{N}S_{\lfloor sN\rfloor}S_{\lfloor tN\rfloor}, possesses a limiting distribution as N goes to infinity, for any s,t \in \mathbb{R}, and that this limiting distribution depends on the initial choice of \alpha and \beta. We then prove optimal tail asymptotics for the limiting distribution. More specifically, we prove that, according to the limiting distribution, the probability of landing outside a ball of sufficiently large radius $R$ for an explicit set of rational pairs (\alpha, \beta) is 0. For all other rational pairs (\alpha,\beta) we show that this probability is asymptotic to \tfrac{C_{\alpha,\beta}D_{s,t}}{\pi^2 R^4}(1 + O_{\varepsilon}(R^{-2 + \varepsilon})) for any \varepsilon > 0, where C_{\alpha,\beta} and D_{s,t} are explicit, positive constants.  These results, in particular, imply that the limiting distribution of \tfrac{1}{N}S_{\lfloor sN\rfloor}S_{\lfloor tN\rfloor} when (\alpha,\beta) are rational, cannot be a Gaussian. This complements existing work of F. Cellarosi and J. Marklof when (\alpha,\beta) \in \mathbb{R}^2\setminus \mathbb{Q}^2, and completes the classification of the limiting tail behaviour of theta sums.

 For the rational parameters that lead to compact support, we are able to prove a uniform bound for generalised theta sums S^f_N (x; \alpha,\beta) := \sum_{n\in \Z} f(\tfrac{n}{N}) e((\tfrac{1}{2} n^2 + \beta n)x + \alpha n), provided the weight function f is sufficiently regular.

abstract: PhD


title: Deciphering the Complexity of Galaxy Structure

subject:
Galaxies
Galaxy observations
Galaxy photometry
Galaxy scaling relations
Numerical methods
Spiral galaxies

abstract: This thesis presents the tools and findings in our investigation of galaxy structure. A first crucial endeavour consisted of assembling a uniform compendium of ``Photometry and Rotation curve Observations from Extragalactic Surveys'' (PROBES) of over 1500 late-type galaxies, the largest sample of its kind, for such investigations. Using PROBES, we were able to characterize the intrinsic properties of the Radial Acceleration Relation (RAR) in spiral galaxies, and verify their consistency with the Lambda Cold Dark Matter (CDM) cosmology and incompatibility with the previously proposed Modified Newtonian Dynamics (MOND) explanation. Further investigations in galaxy structure would require more extensive multi-band surface photometry processing capabilities;  this was achieved by developing the AutoProf software. AutoProf can automatically and efficiently process galaxy images into non-parametric light profiles. It is typically more robust and achieves greater photometric depth than similar codes. Through this thesis work, the PROBES sample and AutoProf code were both released publicly and have already garnered significant attention. With the PROBES sample, an extensive investigation of the scatter of late-type galaxy scaling relations was also conducted. Our novel Bayesian technique enabled the determination of the intrinsic scatter of 36 scaling relations coupled with a most comprehensive comparison with the literature. The novel Bayesian intrinsic scatter technique revealed inadequacies in previous intrinsic scatter measurements, ultimately finding more diversity in galaxy populations than was previously appreciated. These findings, many of them novel, are instrumental for the development and fine-tuning of galaxy formation models.

abstract: PhD


title: Decreation for the Anthropocene

contributor:
Smith, Michael
Philosophy

subject:
Philosophy
Ecology
Environment
Ethics
Simone Weil
Plato
Metaxu

abstract:
This dissertation places the philosophy of Simone Weil into conversation with contemporary environmental concerns in that epoch sometimes referred to as the Anthropocene. Weil’s work has been influential in many fields, including politically and theologically based critiques of social inequalities and suffering, but rarely linked to ecology. There are many reasons for this, including Weil’s own ethical focus on human existence, the notoriously unsystematic nature of her writings, but also, her work’s very specific metaphysical associations which seem to restrict its potential audience. Contra these apparent barriers, this thesis argues that Weil’s work can be understood as offering a coherent approach with potentially widespread appeal applicable to our ethical relations to much more than just other human beings.
This claim is approached through a detailed understanding of two linked concepts in Weil’s work, namely, ‘decreation’; key to Weil’s understanding of ethics as entailing the worldly dissolution of the small-self or ego, and ‘metaxu’, a concept she adapts from her reading of Plato. Decreation is traced though Weil’s accounts of the human faculties she considers give our lives meaning and purpose. Far from being nihilistic, as is sometimes claimed, Weil reveals the ethical possibilities that emerge through truly facing and accepting the reality of each faculties’ orientation towards unattainable ideals thwarted by life’s absurdity, impermanence, and sufferings. Many past environmental thinkers have argued that Plato exemplifies, or even instigates, a form of anti-ecological Western philosophy that is dualistic and other-worldly in terms of its positing a metaphysical realm of timeless ideas exempt from the transformations of this-worldly entanglements. I argue that Weil’s non-traditional reading of Plato reconciles this movement between actual and ideal (metaxu) to the kind of non-dualistic and non-hierarchical “entanglement” necessary for an ecological ethics.
Following the movement of deep ecology, I then suggest that the process of decreation in Weil is an expansion of the self which might also come to include the surrounding earth and a vast assemblage of others. Ultimately, then, the dissertation works with Weil’s thought to suggest a decreative ecological ethics that decenters the human being by cultivating human actions towards an ecological ethics.

abstract: PhD


title: Interleukin-27 Inhibition of Pandemic Influenza A Virus Infection in Human Macrophages Partially Relies on Type I IFNs.

contributor:
Gee, Katrina
Biomedical and Molecular Sciences

subject:
Interleukin-27
Influenza
Interferons
Viral immunology
Infection
Antiviral immunity

abstract: Zoonotic reservoirs as well as high mutation rates make influenza A viruses (IAV) a looming pandemic threat. Recent studies have identified antiviral activities of the cytokine interleukin-27 (IL-27) against several viruses, including seasonal IAV. However, the role of IL-27 during infection with pandemic IAV strains is currently unknown. Here, we demonstrated that IL-27 inhibited pandemic IAV infection (A/New York/18/2009) by type I interferon (IFN)-dependent and -independent pathways. Using THP-1-derived human macrophages, IL-27 treatment was found to dose-dependently inhibit pandemic IAV infection, and this inhibition was associated with increased expression of antiviral genes, such as myxovirus resistance 1 (MX1), radical S-adenosyl methionine domain containing 2 (RSAD2), interferon induced transmembrane protein 3 (IFITM3) and interferon regulatory factor 1 (IRF1). IL-27-mediated upregulation of these antiviral genes was partly reliant on type I IFNs; MX1 and RSAD2 expression was type I IFN-dependent, IFITM3 expression was both type I IFN-dependent and independent, and IRF1 expression was type I IFN-independent. Accordingly, IL-27 inhibition of pandemic IAV infection was reduced, but not completely abrogated, in the absence of type I IFN signaling. Furthermore, IL-27 treatment promoted the production of chemokines important for recruitment of leukocytes, particularly CXCL9 and CXCL10. These findings identify a potential protective role of IL-27 in innate immune responses to pandemic IAV infection and highlight the antiviral therapeutic potential of IL-27.

abstract: M.Sc.