title: An assessment of total coliforms as a water quality indicator for Ontario private drinking water wells

contributor:
Majury, Anna
Brown, Stephen
Hynds, Paul
Environmental Studies

subject:
Groundwater
Public health
Contaminant hydrogeology
Microbiology
Drinking water guidelines
Private wells
Statistical analysis
Total coliforms

abstract: Private drinking water systems in Ontario are unregulated, leaving the maintenance of private wells in the province as responsibilities of well owners. A static non-zero total coliform (TC) concentration threshold of 5 colony-forming units (CFU) per 100 mL is used by the provincial public health laboratory to determine whether protective action should be recommended to private well owners. The current study sought to assess the role of the TC group and associated thresholds as microbial water quality parameters, as the authors hypothesized that static non-zero TC thresholds are not justifiable. A microbial water quality dataset containing 795,023 samples (including TC and Escherichia coli (E. coli) counts) collected from 253,136 private wells in Ontario between 2010 and 2017 was used to this end. To accurately assess the relationship between E. coli and non-E. coli TC, the E. coli count for each sample was subtracted from the TC count, resulting in “non-E. coli coliforms” (NEC). This study analysed NEC and E. coli detection rates to determine the influence of drivers on NEC and E. coli contamination, NEC:E. coli concentration ratios to assess links, if any, between NEC and E. coli contamination, and the relationship between NEC concentrations and E. coli detection rates to determine whether private well TC thresholds can be meaningfully associated with the probability of E. coli presence. Study findings suggest that a static non-zero TC threshold that recommends protective action is not justifiable because seasonal (e.g., precipitation totals and groundwater extraction volumes), spatial (e.g., aquifer type), and well-specific (e.g., well depth and well type) factors influence contamination. As such, it is recommended that the influence of these factors be considered during the development of private groundwater guidelines. Furthermore, no single NEC threshold could be meaningfully linked to the probability of E. coli presence, as findings suggested that the relationship between E. coli detection rates and NEC concentrations is highly dependent on contamination drivers. The authors also proposed that, because NEC:E. coli concentration ratios are influenced by the aforementioned drivers, they may have a role in determining dominant groundwater contamination pathways.

abstract: M.E.S.


title: VIUALIZATION OF FLAME ACCELERATION AND DDT IN AN OBSTRUCTED TUBE

contributor:
Ciccarelli, Gaby
Mechanical and Materials Engineering

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:
Flame acceleration
Detonation propagation
DDT
DDT run-up distance

abstract:
Self-luminous high-speed photography was used to study flame acceleration and DDT inside a fully transparent round tube filled with equally distanced orifice plates. The combustion tube was 288 cm long with an inner diameter of 7.6 cm. Two sets of orifice plates (50% BR and 75% BR) were used. Stoichiometric ethylene-oxygen diluted with nitrogen or argon was used primarily in this study. The reactivity of mixtures was controlled by the initial pressures. Stoichiometric hydrogen-oxygen with 70% and 80% argon dilution were also used to check the effect of cell structure regularity on DDT. The average combustion velocity was measured using high-speed video data. Soot foils were used to determine detonation propagation mechanism, as well as for detonation cell size measurement.
The DDT criterion based on the ratio of the orifice plate opening diameter and the detonation cell size (d/λ≥1) was verified for the 50% BR but was conservative for higher blockage ratios. For 75% BR a galloping detonation mode that travels at an average velocity below the product's speed of sound influences the determination of the DDT limit in the traditional manner based on the velocity. The use of large argon dilution was found to not influence the propagation mechanism and flame acceleration behavior. Also, 70% argon dilution had no noticeable effect on the critical d/λfor 50% BR, and a very small effect for 80% argon dilution, however, the effect was more noticeable for 75% BR. Generally, large argon dilution increases the cell structure's regularity. Soot foil records obtained for 70% and 80% argon dilution show that the structure is very regular but not significantly more than for the nitrogen diluted ethylene mixtures.
DDT run-up distance was obtained using high-speed videos and soot foils. It was determined that the Silvestrini correlation predicts the DDT run-up distance successfully for reactive mixtures. However, for mixtures near the limit, the DDT run-up distance was significantly larger. A basic correlation for the DDT run-up distance was proposed based on the concept of flame acceleration to fast-flame followed by DDT induction distance that depends on the detonation cell size and activation energy.

abstract: M.A.Sc.


title: K-12 STEM LEARNING ECOSYSTEMS: THE ROLE AND POSITION OF UNIVERSITY-BASED OUTREACH UNITS AS KNOWLEDGE BROKERS

contributor:
Cooper, Amanda
Education

subject:
STEM
Outreach
Ecosystem
K-12
Knowledge Broker

abstract:
To address the projected Science Technology Engineering and Mathematics (STEM) workforce needs and future demands in Canada, one strategy involves the promotion of K-12 STEM learning ecosystems. K-12 STEM learning ecosystems consist of formal learning experiences provided to students by educators within schools, as well as informal learning experiences that are directly or indirectly supported by stakeholders. The purpose of this research is to explore the conceptual position and role of Canadian university-based STEM Outreach Units (SOUs) as knowledge brokers within K-12 STEM learning ecosystems.

This dissertation used an explanatory three-phase naturalistic case study approach involving both quantitative and qualitative data collection and analysis to examine each research question. Phase 1 served as a starting point for generating an environmental scan of university-based STEM outreach units across Canada by utilizing an online search strategy to conduct an environmental scan, followed by a website analysis using quantitative descriptive statistics. Phase 2 consisted of an online survey designed with both closed and open-ended questions to explore SOUs organizational features, the conceptualization of K-12 STEM learning ecosystems, and SOUs' role as knowledge brokers. In Phase 3, semi-structured qualitative interviews were conducted with managers of SOUs to generate individual case studies that are used to further explore SOUs views on K-12 STEM learning ecosystems and the concept of SOUs as knowledge brokers.

The first finding from this research suggests that there is a commonality in SOUs' mission statements and target audiences, with a common interest in expanding their efforts towards increasing the number of underrepresented and underserviced youth who are participating in STEM outreach programs such as Black, Indigenous, racialized youth, those from low socio-economic communities, and girls. However, there is a large variability of other organizational features. Looking at the K-12 STEM learning ecosystem, the second finding indicates that SOUs have established mutually beneficial reciprocal partnerships with their host institution, K-12 schools, students, and community groups, and mixed with others. This particular result suggests that SOUs role within K-12 STEM learning ecosystems could be optimized with increased priority towards establishing collaboration, especially with key stakeholders that have the control/power to both enhance and limit youth’s STEM learning experiences. The third finding indicates that university-based SOUs are well-positioned within the K-12 STEM learning ecosystem as knowledge brokers to facilitate, share and communicate STEM knowledge using brokering functions to a variety of target audiences. In fact, many are already delivering initiatives that can be categorized as one of the following high-priority brokering functions: engagement, awareness, and accessibility. There was also an identified common link between SOUs using the brokering functions to purposefully increase the number of underrepresented and underserviced youth in STEM.

The findings of this study affirm that university-based STEM outreach units have a role to play in educating the current K-12 student population, as they comprise the future workforce. This dissertation concludes that university-based SOUs can play the role of STEM knowledge brokers, spanning the boundaries between stakeholders and other participating groups, within a K-12 STEM learning ecosystem. The outcomes and impact of SOUs as knowledge brokers within a collaborative multi-partner K-12 STEM learning ecosystems could yield an increase in the number of young adults with STEM knowledge and skills, that in pursuing post-secondary STEM education and a STEM career, may potentially close the projected Canadian workforce gap.

abstract: PhD


title: Formulations and solution methods for global optimization of the Pooling problem and its extensions

contributor:
Li, Xiang
Chemical Engineering

subject:
Global Optimization
Pooling Problem
Bilinear Programming
P formulation
Multi-commodity Flow
Mixed-integer Bilinear Programming

abstract:
The pooling problem is an important research topic in global optimization. Due to huge economic savings, this bilinear programming problem (BLP) has attracted many researchers in global optimization and boosted the development in this field. The thesis is concerned with formulations and algorithms for the pooling problem and its extensions.

A key issue in global optimization is the mathematical formulation. An engineering problem may be mathematically expressed differently. The computational efforts required by different formulations may vary significantly. The existing formulations use either quality variables (P-formulation and its variants) or split-fraction variables (SF-formulation and its variants) to model the blending effect. However, theoretical comparison of the formulations is only limited to those among the same category.

The first contribution is a theoretical comparison between P- and SF- formulations for the generalized pooling problem (GPP), which focuses on the tightness of the convex relaxations. A formulation that has a tighter convex relaxation is said to be stronger. It is proved first that  P ̂-formulation (an enhanced P) is at least as strong as SF-formulation under bound consistency conditions that are usually satisfied by practical problems. Then P-formulation is proved to be equivalent to the P ̂-formulation under certain conditions.

Knowing the strength of P-formulation, the next contribution improves formulations for the water treatment network (WTN) and total water network (TWN) optimization problem. The proposed P*-formulation can notably reduce the solution time from the existing formulations.

Formulations that track commodity flows are shown to be stronger than their component flow counterparts, but their extension to water treatment networks is challenging due to the existence of treatment units. This thesis proposes a multi-commodity flow formulation for the WTN and proves its strength.

The last contribution is a discretization-based global optimization algorithm for mixed-integer bilinear programming problems (MIBLPs). It is found that the existing fix-base discretization formulation may lead to weak relaxation, and the mixed-integer linear programming (MILP) problem may become unnecessarily large. The proposed algorithm uses a hybrid formulation (H-formulation) which yields tight relaxation and allows flexible numbers of partitions. It is able to solve most of the test problems faster than the global solvers.

abstract: PhD


title: Recognizing Ruins: The Need for an Environmental Ruin Aesthetics in the Anthropocene

contributor:
Knight, Deborah
Philosophy

subject:
aesthetics
environmental aesthetics
nature aesthetics
ruin aesthetics
ruins
modern ruins
anthropocene
Edward Burtynsky

abstract: This thesis identifies the need for an updated approach to ruin aesthetics that integrates recent work in environmental aesthetics alongside discourses about the changing meaning of “nature” in the Anthropocene epoch. By examining the eighteenth-century origins of nature aesthetics and its development into an aesthetics of the environment in the late twentieth century, I reveal how scholarly and popular modes of ruin representation and appreciation evolved in tandem with the aesthetic appreciation of the natural world. This inquiry shows how ruin appreciation ought to be reevaluated in light of contemporary perspectives in environmental aesthetics. As the Classical and Romantic ideals that dominate ruin appreciation reproduce untenable models of humanity’s relationship to nature, I argue that incorporating ruin aesthetics into environmental aesthetics will help widen the aesthetic considerations we view as relevant to the experience of ruins. In describing the prevalence of ruin imagery in contemporary culture, I also demonstrate the necessity of treating recently ruined sites as candidates for aesthetic appreciation. By acknowledging the experiencer’s continuity with ruins, rather than treating these sites as mere traces of ideal forms of the past or as only evoking Romantic images, we can affirm the ecological, social, and aesthetic forces made materially available by ruins of the not-so-distant past. These insights reinforce the importance of closely examining how the concept of the sublime functions in relation to ruins. Recently ruined sites such as deteriorating houses, derelict factories, and industrial wastelands often produce deeply negative responses as we confront what has become of the ruin—and what the ruin is becoming. I argue that, although traditional theories stress the role of negative emotion in the sublime, their emphasis on pleasure as the end of aesthetic experience presents aesthetic and ethical difficulties in the context of environmental degradation and ruination. Drawing on Carolyn Korsmeyer’s account of the sublime in ruin appreciation and Arnold Berleant’s concept of the “negative sublime”, I identify negative responses as being fundamental to contemporary ruin experience. I conclude by underscoring how cultivating greater sensitivity to the spaces we are immersed in ensures that these experiences are meaningful rather than trivial.

abstract: M.A.


title: ADVANCES IN THE DIRECTED ORTHO METALATION, SUZUKI-MIYAURA CROSS COUPLING, AND RING-OPENING REACTIONS OF INDAZOLES. SYNTHESIS OF LUMINESCENT ACRIDINE AND NOVEL INDAZOLE-BASED OXAZABORINES

contributor:
Snieckus, Victor
Stamplecoskie, Kevin
Chemistry

subject:
Organic Synthesis
Metalation Chemistry
Cross-Coupling Chemistry
Borylation Chemistry
Heterocyclic Chemistry

abstract:
The Directed ortho Metalation (DoM) reaction is a ubiquitous tool in the synthesis of polyfunctionalized aromatic and heteroaromatic molecules. Its regioselective nature endowed by the virtue of directed metalation groups (DMGs) coupled with its compatibility alongside many other well-established reactions, has led DoM into the modern age of synthetic organic chemistry.
Chapter one of this thesis begins with a brief review of traditional approaches for the carbon and nitrogen functionalization of indazoles and the reactivity challenges faced therein. This is followed by a comprehensive review of current C-7 substitution strategies and their limitations. It then describes our developments in the regioselective C-7 functionalization of N-1 carbamoylated indazoles using DoM. A variety of electrophiles were well-tolerated, where the metalation / cross-coupling ‘fusion’ is illustrated using DoM-derived halides. We then coupled these methods with the traditionally undesirable ring-opening of 1H-indazoles towards the synthesis of 6-substituted N-(2-cyanophenyl)ureas, molecules difficult to access by conventional means.
Chapter two begins with a brief introduction on the broad applications of indazoles in materials science, followed by a detailed analysis of the key electronic / structural properties of luminescent indazoles. The discussion then shifts to a short review of historical approaches and modern developments in the preparation of N,O-ligand chelated boron(III) complexes - oxazaborines. We then highlight the challenges we faced in synthesis of luminescent indazole-based azaborines, which we circumvented using a key structural modification. Our advances in the synthesis of highly luminescent acridine and novel indazole-based boron(III) complexes are detailed herein. To the best of our knowledge, these are the first oxazaborines of indazole reported in the scope of the current literature.

abstract: M.Sc.


contributor:
McIntire, Gabrielle
English Language and Literature

subject:
Literary Modernism
Christianity
Masculinity

abstract:
Flawed Modernists: Masculinity & Christianity in Eliot and Joyce capitalizes on the resurgence in T.S. Eliot and James Joyce studies by entering the vibrant debates surrounding their representation of gender, colonialism, and faith. The recent availability of Eliot’s Poems (2015), Complete Prose (2014-19), and Letters (ongoing) offers a unique opportunity to understand modernism’s most enigmatic poet; I thus turn to his oft-neglected Bolo writings to gain a fresh perspective on Eliot. The focus on his non-canonical poetry opens peculiar, albeit compelling connections with Joyce’s Portrait of the Artist as a Young Man and Ulysses. In these novels, Joyce puts forth paradoxical, idiosyncratic opinions on gender, colonialism, and faith that the scholarship is still trying to comprehend.

Critics have yet to fully recognize that Eliot’s goal with Bolo was twofold: Eliot deployed Bolo at times of transition in his life – beginning university (1906), moving to London (1914), converting to Christianity (1927) – to help him establish friendships and to begin untangling complicated topics. As he approached manhood, Eliot circulated Bolo Poems that articulate his skepticism towards American colonialism. During his conversion to Christianity, Eliot turned to Bolo to comprehend Anglo-Catholicism’s emphasis on the via media. In Joyce’s case, Portrait and Ulysses present us with an ironic originality, a type of avant-garde writing that draws much of its inspiration from historical and literary precedents. Portrait seeks to enlarge what qualifies as acceptable masculine behaviour in turn-of-the-century Ireland, doing so by consistently depicting Stephen’s effort to overcome his culture’s prescribed masculine ideals. In Ulysses, Joyce draws on Old Testament wisdom literature to sustain his foray into sexual spirituality in “Circe,” an ironic move given his self-professed hostility toward the church.

abstract: PhD


title: The Effects of Geologically-Realistic Heterogeneity on Stray Gas Migration and Mass Transfer

contributor:
Mumford, Kevin
Civil Engineering

subject:
Stray Gas
Mass Transfer
Light Transmission
Hydrogeology

abstract:
Natural gas production is expected to be sustained until 2030 in North America, with demand rising, in part due to ‘coal-to-gas switching’. Natural gas wells can leak, resulting in stray gas migration, which can be detrimental to the environment. The goal of this research was to investigate stray gas migration and mass transfer in geologically-realistic bed-scale heterogeneity, for the purposes of better conceptualization and improving field-scale modelling and monitoring techniques. This goal was achieved by conducting methane injection and dissolution experiments in a medium scale (39.6 cm × 40 cm × 1.15 cm) quasi-two-dimensional flow cell packed with heterogeneous or homogeneous deposits. Geologically-realistic bed-scale microheterogeneous structures were created using a newly developed modified 3D printer depositional apparatus. Sand packs were assessed for structural similarity to replications of themselves, and replication of gas migration was assessed between and within packs by injecting gas once into five replicate packs and injecting gas five times into a sixth replicate. Gas saturations throughout injection and after relaxation were quantified using the light transmission method (LTM). After gas relaxation, water was pumped through the cell and integrated aqueous samples were collected to measure concentration in time.
The printer-based packing method showed good reproducibility of the geologically realistic microheterogeneous structures (herringbone cross beds). It showed good reproducibility of the macroscopic characteristics of the gas migration structure within the same and between different packs, but at the near-pore scale replication cannot be achieved. LTM results showed that methane migration is significantly impeded by capillary barriers created by heterogeneous deposits, and that the gas storage capacity can be as high as 12.2% of the pore volume at the scale of the flow cell for the heterogeneity configurations tested.  Dissolved methane concentrations compared with estimates of source mass showed the rate of mass transfer to be close to a 1-to-1 relationship, and it is less sensitive to initial source mass conditions than has been reported previously for upscaled DNAPL mass transfer due to gas persistence and a reduced change in interfacial area.

abstract: M.A.Sc.


title: Theory and Application of Kernel Estimation Methods for Covariate-Varying Effects in Survival Analysis

contributor:
Jiang, Wenyu
Chen, Bingshu
Mathematics and Statistics

subject:
Survival Analysis
Kernel Smoothing
Simultaneous Confidence Bands
Biomarker Study

abstract:
Study of prognostic and predictive biomarkers play an important role in the design and analysis of clinical trials.
The development of personalized medicine calls for the investigation of the biomarker effect on the treatment in survival analysis.
To study the treatment-biomarker interaction, we employ kernel smoothing techniques to propose two methods.

One is to use the Cox model under the proportional hazard assumption, where the treatment coefficient is modeled as a function of a biomarker without specifying the functional form.
We study this model with multivariate covariates, and contribute to the theoretical development.
We discuss the maximal deviation of the estimate, then construct simultaneous confidence bands for both coefficient and derivative functions.

When the proportional hazard assumption is violated, we propose to use restricted mean survival time as the tool to study the association between the treatment and biomarker.
We apply kernel regression to make statistical inference for the one-sample problem of the biomarker effect on the restricted mean survival time.
We then study the two-sample problem with the same method. Treatment-biomarker interaction here is modeled as the difference of the restricted mean survival times on the same level of biomarker between treatment groups.

For both methods, multiple confidence bands are built and associated hypothesis testing problems are discussed.
We assess the proposed methods in extensive simulation studies, and find good finite sample performance.
We also apply the methods to real world clinical trial datasets to demonstrate how the treatment effect is associated with the varying level of the biomarker.

abstract: PhD


title: Examining the Association Between Change in Non-exercise Estimated Cardiorespiratory Fitness and Mortality in Men

contributor:
Ross, Robert
Kinesiology and Health Studies

rights: Attribution-NonCommercial-NoDerivs 3.0 United States

subject:
cardiorespiratory fitness
mortality
cardiovascular disease

abstract:
Cardiorespiratory fitness (CRF) is a strong, independent predictor of morbidity and mortality. The addition of CRF to cardiovascular disease (CVD) risk prediction algorithms enhances individual risk stratification. However, CRF is not routinely measured in health care settings as exercise testing is neither feasible nor appropriate to perform during most patient encounters.

Non-exercise estimated CRF has been suggested as a pragmatic alternative to exercise testing. While initial evidence suggests that estimated CRF is an independent predictor of mortality beyond age, biological sex, race, and traditional CVD risk factors, these findings are based on prospective cohort studies that use a single baseline measure of CRF. Consequently, these studies may be subject to exposure misclassification and residual confounding. By examining the change in estimated CRF over time, these issues can be mitigated. Therefore, the purpose of this thesis was to investigate whether change in estimated CRF is associated with CVD and all-cause mortality risk.

We examined data from 10445 men who participated in the Aerobics Center Longitudinal Study between 1979 and 2002. Participants completed two comprehensive medical examinations and were then followed for mortality or until December 31st, 2003. Change in estimated CRF was derived using the Jackson et al. (2012) and Nes et al. (2011) algorithms.

Our findings suggest that the association between change in estimated CRF and mortality is equation dependent. Whereas change in estimated CRF using the Jackson equation was independently associated with CVD and all-cause mortality, change in estimated CRF using the Nes equation was not associated with mortality. Nevertheless, implementation of estimated CRF assessment in health care settings provides an opportunity for practitioners to counsel patients on the importance of physical activity and provides a metric to assess treatment efficacy.

abstract: M.Sc.


title: Understanding spatial patterns of past aridity on the Canadian prairies over the Holocene: insights based on diatom assemblages from Success Lake

contributor:
Cumming, Brian
Biology

subject:
Paleolimnology
Canadian prairies
Lake Salinity
Diatom
Drought
Holocene

abstract:
The Canadian prairies receives little precipitation and hence is prone to drought-related environmental, economic, and social impacts. Previous studies have suggested the Canadian prairies are sensitive to extreme droughts, and during the warmer mid-Holocene, many lakes became increasingly saline or dried out. Understanding the Holocene aridity profile is critical for us to be able to confidently forecast future drought and aridity, which is essential to establish appropriate policies and programs to reduce negative impacts.
Diatom assemblages preserved in Success Lake sediment were used to reconstruct changes in lake-water salinity, with increases in salinity, serving as a proxy of enhanced aridity over the Holocene on the Canadian prairies. The diatom record from Success Lake revealed four periods that were defined based on diatom composition. Century-scale analysis of the diatom record during the Holocene is consistent with a drier climate in the mid Holocene (between ~7,000 to ~5,300 cal yr BP) and is represented by high abundance of Cyclotella choctawhatcheeana. Between ~5,300 cal cal yr BP to 3,300 cal yr BP, short-lived high frequency in Chaetoceros muelleri implies the period of wetter events within sustained arid conditions throughout the mid-Holocene. Analysis of the past ~3,000 years suggests that the late Holocene was more complex, with extended periods of increased variability in diatom assemblages and inferred salinity suggesting frequent oscillation between the rise and falls in effective moisture. The mechanism controlling the moisture gradient is likely associated with the change in intensity and shape of the jet stream, influenced by ocean-atmospheric interaction and solar radiation. Comparing the record from Success Lake with other paleoclimatic records from the Canadian prairies and regions from near the ecotone of mixed-grass prairies and the Aspen parkland, show that lakes on the mixed-grass prairies experienced much less intense variation in effective moisture than the lakes adjacent to the Aspen Parkland region, highlighting this ecotone to variations in effective moisture.

abstract: M.Sc.


title: Surface features of the cold/temperate transition zone at White Glacier terminus, Axel Heiberg Island, Nunavut.

contributor:
Thomson, Laura
Geography and Planning

subject:
Glaciology
Photogrammetry
Arctic Glaciers
Structural Glaciology
Remote Sensing
Polythermal Glaciers

abstract:
The historical records of White Glacier (WG), a polythermal valley glacier found in northern Nunavut, Canada, are used alongside modern structural models and orthomosaics produced from Structure from Motion photogrammetry to assess change in the terminus region. Recognizing the surface expression of terminus change contributes to the understanding of ice dynamics and improves the potential for regional glacier assessment by providing target features to be interpreted through remote sensing methods.

Elevation models from 1960, 2011, 2018 and 2019 of various origins were homogenized. The geodetic mass balance of the terminus region was measured from co-registered digital elevation models (DEMs) and found to have contributed 21 \% of the total volume loss of WG between 1960 – 2014, while only consisting of 7 \% of the total glacier surface area, consistent with past findings. Surface structures at WG terminus were assessed using nadir imagery captured between 1960 – 2019. Signs of decreasing ice dynamics were observed, indicative of a stagnating terminus experiencing retreat conditions. Compressive strain is thought to reactivate crevasse traces as they transit the terminus icefall, leading to the formation of novel arcuate band features through recrystallization.

Surveys of reflective prisms and optical feature tracking results between 2018 – 2019 were used to measure modern ice velocity and strain rate components, while DEMs and interpolated mass balance measurements were used to calculate ice emergence velocity between 1960 – 2018. Early emergence indicates that ice uplift occurred in the terminus lobe from compressive strain increasing with distance down-glacier. Annual strain indicates that modern ice flow is less obstructed above the terminus icefall, and enters a zone of moderate compressional deformation in the terminus lobe below, while the magnitude of emergence has decreased. This difference, paired with a reduced temperate ice extent measured in comparison to the 1970s, is possibly due to limited basal motion permitted through efficient sub-glacial hydrologic channels. The persistence of the temperate ice region is thought to have become increasingly dependent on the influx meltwater to the glacier bed.

abstract: M.Sc.


title: Seasonal Responses of Soil Nitrogen and Carbon Cycling Processes to Cold Season Warming in High Arctic Wet Sedge Tundra

contributor:
Scott, Neal
Geography and Planning

subject:
Arctic
Climate Change
Carbon Cycling
Nitrogen Cycling

abstract: Arctic warming and changes in precipitation regimes are expected to increase soil nitrogen (N) availability by stimulating microbial activity and releasing N stored in permafrost. How much contribution cold season warming is going to have, if any, on increasing available N pools and greenhouse gas fluxes is poorly understood. The cold season, a term used to describe the extended Arctic winters, is warming at twice the rate of the growing season, which can alter the soil environment and soil biogeochemistry. In this thesis, I examined changes in soil carbon (C) and N cycling processes in terrestrial Arctic ecosystems, and how they might change in response to cold season warming. I conducted a 50-day laboratory incubation study where I incubated soils mimicking the annual soil thermal regime with different cold season treatments (-10˚C, -15˚C, -20˚C, -25˚C). Throughout the study I measured soil inorganic N pools and cycling rates, and fluxes of the major greenhouse gases (CO2, CH4, and N2O).  Over the cold season, both coldest and warmest treatments behaved similarly and displayed high N immobilization rates. Before thaw, extreme cold season warming lead to an increase in soil NO3- concentrations which were immediately lost at thaw. Although cold season fluxes of CH4 and CO2 differed with temperature, cold season warming did not affect growing season flux rates. The results indicate cold season is a critical period when changes in temperature, moisture, and substrate availability can lead to distinct biogeochemical outcomes at different stages of the annum. I conclude that cold season warming can play a crucial role in the seasonality of High Arctic C and N cycles.

abstract: M.Sc.


title: Commodifying Baul Spirituality: Changing Baul Literature and Music in Bangladesh

contributor:
Walker, Margaret E.
Walker, Margaret E.
Cultural Studies

subject: Baul Spirituality

subject: Baul Music

subject: Baul Literature

subject: Baul Studies

subject: Commodification and Baul Culture in Bangladesh

subject: Popular Music and Baul Culture in Bangladesh

subject: Folk Music, Literature, and Spirituality in Bangladesh

subject: Popular Music, Baul Folk Culture, and Commodification in Bangladesh

subject: Music Industries and Baul Culture in Bangladesh

subject: Performer and Practitioner Bauls in Bangladesh

subject: Tradition, Authenticity, and Change in Baul Music and Literature in Bangladesh

subject: Agency and Bauls in Bangladesh

subject: Commodification and Loss of Baul Spirituality, Music, and Literature

abstract: The Bauls, itinerant minstrels of rural areas of Bangladesh and West Bengal, India, follow a practice that combines elements from both monotheistic and polytheistic beliefs centered around spiritual experiences that prioritize humanism and nature-centered philosophy over all other endeavors. This interdisciplinary project is a unique attempt to study heterogeneous Baul traditions by investigating the changes in Baul music, literature, and Baul communities. My study examines whether, in Bangladesh, commodification impacts the supposed devaluation of Baul spiritual philosophy and whether the concept of agency for Bauls provided by the music industry detracts from the spiritual impact of Baul music. As a study that brings together literature, spirituality, cultural theory and ethnomusicology, this research aims to document and disseminate a comprehensive representation of the spiritual philosophy of Baul music and poetry, while critically analyzing the changes in Baul cultural production in the context of popular and consumer culture in Bangladesh. I begin by exploring the aspects of Baul philosophy and rituals. Then, this study investigates the issues of cultural change impacting the concepts of Baul tradition and authenticity. Afterwards, I examine the changes in the evidence collected from contemporary Baul music in Bangladesh and discuss how such changes devalue the Baul beliefs, literature, and music. I then turn to the question of agency; whether commoditized Baul literature and music offers Bauls agency and whether, in fact, the concept of agency in this context is illusory. And finally, I investigate the intersection of Baul spirituality with these changes and discuss how the changed cultural productions threaten Baul spirituality, literature, and music.

abstract: PhD


title: The Investigation of Dimethylaminoethanol (DMAE) as a CO2-Responsive Draw Solute for Forward Osmosis

contributor:
Champagne, Pascale
Cunningham, Michael
Civil Engineering

subject:
Forward osmosis
Desalination
Draw solute
Water treatment

abstract:
Water scarcity and the limited amount of freshwater resources available worldwide is driving the need for more sustainable water treatment methods. The reverse osmosis (RO) process is a common desalination method, but is energy intensive due to the high external pressure requirements of the system. Thus, low-energy alternatives are needed. Forward osmosis (FO) is a membrane-based process which does not need external pressure to drive the system, but instead uses a high osmotic pressure solution, the draw solute, to drive the process. Therefore, the FO process has the potential to be superior than RO through reduced energy requirements. Currently, the performance of the FO process is largely dictated by the draw solute. The search for an ideal draw solute is critical in making FO more techno-economically viable.
In this thesis, first, non-stimuli responsive draw solutes were tested for their FO performance. An FO custom-built bench-scale setup was used to investigate the draw solutes NaCl, MgSO4, polyethyleneimine (PEI) and poly(acrylic acid) sodium salt (PAA-Na) in terms of water flux. The performance of the draw solutes was compared and it was found that 2 M NaCl solution generated high initial and average flux values of 28.1 L m-2 h-1 (LMH) and 14.5, respectively. The flux values of these conventional draw solutes were also successfully compared to literature to validate the FO system. Next, a CO2-responsive draw solute, dimethylaminoethanol (DMAE), was explored. The best performing draw solute was the protonated 40 wt% DMAE solution which generated the highest initial flux of 47.1 LMH and average flux of 13.6 LMH. This draw solute was then tested against a model seawater feed yielding an initial flux of 12.6 LMH and an average flux of 8.3 LMH. DMAE successfully showed good promise as a draw solute for FO in this research as a proof-of-concept study. However, future work will be needed to further evaluate and optimize DMAE for FO.

abstract: M.A.Sc.


title: Single- and Multi-component Transport of Per- and Polyfluoroalkyl Substances (PFAS) in Unsaturated Porous Media

subject:
PFAS
PFAS Transport
Interfacial Adsorption
Air-Water Interface
PFOS
PFOA
Retention

abstract: Per- and polyfluoroalkyl substances (PFAS) are highly persistent contaminants that pose a risk to both humans and the environment. Understanding the transport of these compounds in groundwater systems is crucial to risk characterization and remediation efforts. An important part of this understanding is the adsorption of PFAS at the air-water interface. The goal of this research was to improve the overall understanding of PFAS transport by examining the retention and release of individual PFAS and PFAS mixtures in a trapped gas (quasi-saturated) system. One-dimensional, small-scale laboratory experiments were completed using 5.1 cm- or 7.6 cm-diameter, 20 cm-long columns packed with sand and containing trapped gas. Various PFAS solutions, including single- and multi-component mixtures, were pumped through the unsaturated columns and effluent samples were analyzed to develop breakthrough curves. The results of these experiments indicated that PFAS air-water interfacial adsorption is enhanced under low concentration conditions, which is captured by the Freundlich isotherm. Increases in PFAS surface activity also enhanced interfacial adsorption. The release of single-component PFAS exhibited tailing, which was similar in PFAS mixtures. Tailing has implications for source zone longevity and should be considered at the field scale. PFAS mixture experiments showed competitive sorption effects, where the more surface active component(s) outcompeted the less surface active component(s) for adsorption at the air-water interface. These effects led to accelerated arrival of the less surface active component(s). The presence of hydrocarbon surfactants in AFFF experiments also accelerated less surface active PFAS arrival. Additionally, representing a PFAS system as ‘total PFAS’ will overestimate the arrival of certain compounds and underestimate the arrival of others. These effects were observed for isomers of PFOS and among different PFAS compounds. Overall, this research highlights the importance of identifying PFAS and other surface active components during the characterization of PFAS-impacted sites, as compounds will be transported according to their individual surface activities in concert with mixture effects.

abstract: M.A.Sc.


title: Engineering Insulin: A Manipulative Study on the Activating and Inhibiting Properties of Insulin/Insulin-Like Peptides (INS) in Caenorhabditis elegans

contributor:
Chin-Sang, Ian
Biology

subject:
Caenorhabditis elegans
insulin
modification
INS
worm
IIS
DAF
PTEN

abstract: The insulin/insulin-like growth factor signalling (IIS) pathway is evolutionarily conserved between humans and the nematode, Caenorhabditis elegans. While humans only encode activating insulins, C. elegans remarkably encode both activating and inhibiting insulin/insulin-like peptides (INS). Furthermore, strongly activating C. elegans INS contain an F-peptide, where previous work suggested that it may be required for activating activity in certain insulin signalling contexts. However, much is still unknown as to what differentiates an activating insulin from an inhibitor. Previously, the Chin-Sang lab categorized all 40 INS coding genes of C. elegans in relation to their activity on the IIS pathway. Amino acid sequence alignments between the human insulin/insulin-like growth factors and the strongest activators of the C. elegans INS superfamily reveal conserved Glycine residues adjacent to the B-chain/domain disulfide Cysteines. Interestingly, these Glycine residues are not conserved in inhibiting C. elegans INS. I hypothesize that these conserved Glycine residues are vital for the activating properties of INS. To determine this, I overexpressed multiple insulin-like variants and observed their effects on phenotypes associated with abnormal IIS signalling. I report that the B-domain disulfide adjacent Glycine residues are important for activating activity and that I can change a strong activator, like INS-4, to an inhibitor by changing the Glycine residues to Proline. I provide further evidence for the importance of these Glycine residues in conferring activating properties as I could change a strong inhibitor like INS-37 to function as an activator by changing its B-domain disulfide adjacent residues to Glycine. I report that the F-peptide has activating properties and can function as a modulatory activator in F-peptide deficient INS but is specific in only promoting Q-cell divisions. My study is first to show that changing the conserved disulfide adjacent residues is sufficient to alter INS behaviour on the IIS pathway. My work will provide vital information for medical applications in treating insulin-related oncogenic and neurodegenerative disorders as well as progress the current knowledge on insulin/insulin-like peptide properties.

abstract: M.Sc.


title: The Application of Biogeocementation to the Stabilization of Coal Tailings from the Victoria Junction Tailings Basin: a Bench-Scale and Pilot-Scale Study

contributor:
Champagne, Pascale
Mann, Vanessa
Civil Engineering

subject: Coal tailings

subject: Stabilization

subject: Microbially induced calcite precipitation

subject: Sporosarcina pasteurii

abstract:
The Victoria Junction Tailings Basin (VJTB), located in Cape Breton, Nova Scotia, currently stores sulfidic, acid-generating coal tailings sub-aqueously. Costs and ongoing maintenance requirements for the impoundment have necessitated alternative tailings stabilization methods to be explored, such that the potential for acid rock drainage and metal leaching (ARD/ML) can be minimized. Biogeocementation is a growing field of study for both the physical and chemical stabilization of earth materials, whereby microorganisms facilitate the formation of calcium carbonate deposits to cement soil particles. This treatment has the potential to improve the mechanical properties of soil and increase porewater pH. In this thesis, the feasibility of using biogeocementation as a method of stabilizing VJTB tailings was evaluated.
The treatment was first evaluated on a bench-scale using the ureolytic bacteria, Sporosarcina pasteurii. The application of S. pasteurii and treatment solutions to undrained tailings achieved a 453% increase in soil compressive strength, and a 72% increase in calcium carbonate (CaCO3) content compared to untreated tailings. The initial saturation of tailings and the distribution of treatment solutions via surface application contributed to improvements to the mechanical properties of tailings. Additionally, bacterial populations native to the tailings were stimulated by MICP treatment solutions.
	A pilot-scale study was undertaken to evaluate the scalability of biogeocementation for its potential use at the VJTB. Four large-scale application methods for S. pasteurii and treatment solutions were investigated: (1) spray irrigation, (2) rotary cultivation, (3) excavation of shallow trenches, and (4) pre-mixing of tailings. After a 28-day incubation period, the spray irrigation method resulted in the most successful treatment with notable improvements in compressive strength and CaCO3 content. Pilot cells had elevated concentrations of viable bacteria and lower concentrations of sulfate relative to the control. The work outlined in this thesis supports the feasibility of using biogeocementation in the weeks following the removal of a water cover for the stabilization of VJTB tailings on both a bench and pilot scale. Additional research is necessary to determine the physical and chemical stability of the material over the months and years following MICP treatment.

abstract: M.A.Sc.


title: Hydrogen peroxide regulates a cation channel to control neuroendocrine cell excitability

contributor:
Magoski, Neil
Biomedical and Molecular Sciences

subject:
cation channel
bursting
peptidergic neuron
H2O2
mollusk
reproduction
diacylglycerol
inositol trisphosphate
oxidation

abstract:
Non-selective cation channels promote neuronal spiking in many animals.  For the hermaphroditic marine snail, Aplysia californica, synaptic input to neuroendocrine bag cell neurons triggers various cation channels, causing an ~30-min afterdischarge of action potentials and egg-laying hormone secretion.  During the afterdischarge, protein kinase C (PKC) elevates hydrogen peroxide (H2O2), likely by stimulating nicotinamide adenine dinucleotide phosphate oxidase (NOX).  Here, I show that in whole-cell voltage-clamped single, cultured bag cell neurons, H2O2 elicited a prolonged, concentration- and voltage-dependent inward current, associated with an increase in membrane conductance, an ~+30 mV reversal potential, and a requirement for extracellular cations.  This current was inhibited by cation channel blockers, and boosted or lessened by preventing or enhancing cellular reduction, respectively.  Under current-clamp, H2O2 stimulated bursting in single neurons and evoked afterdischarges from bag cell neurons in intact clusters.
During the afterdischarge, phospholipase C (PLC) hydrolyzes phosphatidylinositol-4,5-bisphosphate (PIP2) into diacylglycerol (DAG) and inositol trisphosphate (IP3).  Pharmacologically activating PLC, or adding a DAG analogue plus IP3, enhanced both the current as well as the frequency of firing brought about by H2O2.  Stimulating PKC with phorbol ester caused both a voltage-dependent current, that reversed at ~+30 mV, and augmented H2O2-induced spiking.
Because H2O2 is produced intracellularly, it may gate the cation channel at a cytoplasmic site.  Consistent with this, the H2O2-induced current had a relatively slow activation latency and was sensitive to redox modifiers delivered intracellularly but not extracellularly.  In addition, intracellular activation of NOX evoked a current that occluded the H2O2 response.  Moreover, H2O2 enhanced cation channel activity in excised, inside-out patches, where the intracellular face is exposed.
The mitochondria are a potential source of H2O2 as well as being a Ca2+ reservoir.  Releasing mitochondrial Ca2+ with a protonophore augmented the H2O2-induced current, and this was prevented by buffering Ca2+ with high intracellular EGTA.  Futhermore, the H2O2-induced current was lessened by a mitochondrial-targeted antioxidant.
These results suggest that oxidation by H2O2 activates a voltage-dependent cation channel in bag cell neurons.  The synergy of H2O2, phosphoinostide metabolites, and mitochondrial Ca2+ in promoting bursting has implications for neuroendocrine function in Aplysia and the wider animal kingdom.

abstract: PhD


title: Thanks for the 'Memoir'ies: The Impact and Importance of Appalachian Trail Literature to Hiking Culture

contributor:
Pappano, Margaret
English Language and Literature

rights: Attribution-NonCommercial 3.0 United States

subject:
Travel Literature
Appalachian Trail
Culture
Thru Hiking
Memoirs
Social Media

abstract:
This paper is composed of a literary study on the memoirs and social media posts written
or made by people who have thru or section hiked the Appalachian Trail in its entirety in order to
better understand the culture of the Appalachian Trail, the motivations of the hikers, and the
impact literature can have on the trail. The study looked at published memoirs set between 1948
to 2005, as well as interviews and social media posts up to 2021 surrounding thru hikers and
their progress along the trail. The study also analyzed the impact thru hiking has on individuals
and how literature plays a part in strengthening their connection to the Appalachian Trail even
after they have completed their hike. In addition to the literary study, there is also an experiential
section of the paper dedicated to my firsthand accounts of hiking the Appalachian Trail, being
involved in thru hiker culture, and making my own contribution to the tradition of trail literature
that is as connected to the trail as the act of hiking itself. This topic is worth examining because it
investigates the connections between literature and long-haul hiking, as well as examining how
literature fits into, and tracks changes in, the culture of Appalachian Trail thru hikers, something
not before researched from a literary perspective. The findings show that literature is an integral
part of what has become a “linear community,” along the 14 states that make up the Appalachian
Trail, and that every piece of literature or social media post made regarding the Appalachian
Trail works to add to this culture. This research can be used in the future to assess how the
literature has become an accurate reflection of the culture insomuch that it can be used to form a
base to which analysis of thru hiker culture can be conducted.

abstract: M.A.


title: Using the Arts to Foster Emotional Regulation for Grades Four to Ten Students With ADHD and Attention and/or Hyperactivity Challenges: A Multiple Case Study

contributor:
Bolden, Benjamin
Education

subject:
ADHD
Self-Regulation
Emotional Regulation
Emotional Self-Regulation
Arts Education
Junior-Intermediate

abstract: Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common child mental health disorders (American Psychiatric Association, 2013). Students with attention and/or hyperactivity challenges (AHC) may have deficits in executive functions (EFs) which are required for self-regulation (McClelland & Cameron, 2012) and may be important in managing impulses and emotions in classroom contexts (Rapp-Paglicci, Rowe, & Stewart, 2011). Emotions can trigger a cascading effect in the body and mind making it difficult to self-regulate (Shanker, 2013). Therefore, it is valuable to provide students with emotional regulation (ER) strategies before and during their youth, so they have a skillset to be more successful at school and in life. The potential of the arts to support students’ ER has not been fully explored. The purpose of this qualitative study was to examine how students with AHC experience the arts and ER at school. A multiple case study approach (Stake, 2013) was used to illuminate this phenomenon across six cases: three junior-intermediate (JI) teachers who teach or have taught students with ADHD or AHC and three JI students with ADHD. A semi-structured virtual interview was conducted with each participant separately. Thomas’ (2006) general inductive qualitative approach was used for data analysis. Findings unpack how teachers’ pedagogical orientations influenced them to facilitate and prepare students with AHC to leverage the arts for ER. Additionally, the data showed how the arts can emotionally regulate these students and times where the arts can lead to dysregulation. This research has the potential to benefit multiple stakeholders including students with AHC, JI teachers, and policy-makers.

abstract: PhD


title: Why Do We Have Patellae? An Investigation of Patellofemoral Function and Dysfunction

contributor:
Rainbow, Michael
Mechanical and Materials Engineering

subject:
Biomechanics
Patellofemoral joint
Musculoskeletal modeling
Statistical shape modeling
Patellofemoral pain

abstract: The patellofemoral joint is crucial to the mechanical function of the knee extension mechanism. The patella intricately articulates with the trochlear groove of the femur and allows the transfer of quadriceps force to the tibia. It is difficult to measure patellar motion because it moves beneath skin and soft tissues; therefore, when studying the knee extensor mechanism, patellar kinematics are often simplified to functions of knee flexion angle. Since the patellofemoral joint moves with six-degrees-of-freedom, this oversimplification does not provide a full understanding of the patella’s mechanical contributions. Furthermore, these simplifications do not include subject-specific shape effects that influence the mechanical function of the joint. In this work, I used statistical shape modeling and data-driven musculoskeletal models to investigate the impact of patellofemoral morphology on knee mechanics. I found that patella shape modulates the ratio of quadriceps force and patellar ligament force across individuals. I then identified functional differences caused by energetically different dynamic motions in walking and running. I simulated knee motion with a lower-limb musculoskeletal model to investigate the knee extension moment arm and the importance of its variation with patella articulation. I found that out-of-plane motion and knee flexion angle affects the moment arm length throughout knee motion. This variation may have mechanical importance in knee angular acceleration with a constant applied force. Finally, I examined patellofemoral mechanics in individuals with patellofemoral pain with and without foot orthoses as an intervention. Since patellofemoral pain is thought to be induced by irregular lower-limb mechanics, medial wedge foot orthoses are designed to alter ankle mechanics and increase the knee adduction moment to reduce pain. I generated a statistical shape model to relate knee morphologies to orthotic response. Modes of variation describe shape features that increased knee adduction moment with foot orthoses. Contrary to clinical rationale, foot orthoses increased patellar contact pressure during midstance though the response is likely subject-specific. This work emphasizes the importance of using subject-specific parameters and three-dimensional motion when researching patellofemoral mechanics. A better understanding of the patella’s functional role and the shape-function relationship will ultimately improve clinical recommendations and development of interventions to promote ideal patellofemoral motion.

abstract: PhD


title: The Parochial Kuwaiti Arbitration Regime: A Case Study of the Extension of Arbitration Agreements to Non-Signatories

subject:
International commercial arbitration
Extension of arbitration
Non-signatories
Third parties in arbitration
Governing law
Consent in arbitration
Implied consent
Alternative dispute resolution

abstract:
As embodied in the Kuwaiti government’s recent initiative, the New Kuwait Development Plan 2035, Kuwait’s aspirations to decrease its habitual oil dependency through economic diversification has led the country to undergo major law reform and regulation overhaul. However, forgotten in this burst of regulatory innovation are the statutes that collectively govern arbitration in Kuwait. The continuing underdevelopment of Kuwait’s arbitration laws undermines the country’s efforts to materialize its aspirations be an attractive destination for foreign direct investment.
Arbitration is now considered a principal method—in some industries and regions, the principal method—of resolving international commercial disputes. However, arbitration is not equally perceived across all jurisdictions. Some jurisdictions, including Kuwait, maintain a parochial perspective on arbitration as an exceptional means of dispute resolution that ousts the inherent jurisdiction of national courts, leading them to lay idiosyncratic requirements as to the form of a valid arbitration agreement and restrict arbitral jurisdiction more generally. Conversely, most jurisdictions have by now adopted a more liberal position towards arbitration as a method of dispute resolution alternative—rather than subordinate—to court litigation.
Kuwaiti private law is largely based on Egyptian law, which was in turn heavily influenced by French law. Despite the continuing similarity between the Kuwaiti, Egyptian and French legal systems, they vary significantly in the way they perceive arbitration. As this thesis will argue, these divergent perceptions of arbitration explain, to a great extent, the disparity of doctrines and legal principles recognized under each of the jurisdictions’ laws, scholarly writings, and court rulings. In particular, the delicate issue of extension of arbitration agreements to non-signatories, which is regulated neither by international instruments nor by national laws, remains largely unsettled. This particular issue demonstrates the disparity between the three jurisdictions to deal with complex questions such as arise in modern international commercial arbitration practice.
In order to understand the current state of Kuwaiti law and how it might be improved, this thesis examines how Kuwait, Egypt, and France approach a range of issues that arise in international arbitration, focusing in particular on a case study of the extension of arbitration agreements to non-signatories. It is hoped that this research will generate effective reforms to Kuwaiti arbitration laws that will also be consistent with the Kuwaiti legal system, in order to support the country’s aspirations of becoming an international financial hub.


title: The Development of Novel Bio-Based CO2-Responsive Polymers for Binder Applications

contributor:
Jessop, Philip
Chemistry

subject: CO2

subject: Polymer

abstract: CO2-switchable materials use CO2 as the trigger to induce a change in one or more of the material’s physiochemical properties. The mechanism of switching, in most cases, is the reversible protonation of tertiary amines in aqueous solution in the presence of CO2 but not in its absence. This type of stimuli-responsive materials is attractive since the trigger CO2 is a benign and non-toxic gas. The application of CO2-switchable materials could be well suited to binder polymers in various coating formulations, such as the preparation of polymer latexes. In addition, the environmental impact of these polymers could be reduced and the sustainability improved as fatty acids from renewable sources are used as the precursors for polymer synthesis. To convert natural fatty acids to polymers, two steps were followed: 1) functionalization of fatty acid with 2-hydroxyethylmethacrylate (HEMA); 2) free radical polymerization of the bio-based monomers using azoisobutyronitrile (AIBN) or benzoyl peroxide (BPO). A series of homopolymers and copolymers were synthesized by varying two main factors: the content of the bio-based material present in the polymer and the ratio of alkyl to tertiary amine containing monomers. CO2-switchable monomers, derived from lauric and oleic acid, were synthesized and polymerized individually or jointly with 2-(dimethylamino)ethyl methacrylate (DMAEMA) to prepare CO2-responsive polymers. To incorporate tertiary amines to fatty acids, two synthetic strategies were used: 1) halogenation, followed by substitution with an amine; 2) epoxidation of unsaturated C=C, followed by ring opening with an amine.  1H NMR, 13C NMR, FTIR, GPC and mass spectroscopy were used to characterize the novel monomers and polymers. The CO2-responsiveness of the various polymers was tested by electrical conductivity and 1H NMR spectroscopy. The thermal behavior of the synthesized polymers was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The newly synthesized copolymer poly(N,N-dimethylaminoethyl methacrylate-co-2-(methacryloloxy)ethyl dodecanoate) (p(DMAEMA-co-MAED)) exhibited a change in its physical and chemical properties when exposed to CO2 in aqueous solution.

abstract: M.Sc.


title: High-Performance Interconnect-AwareMPI communication for Deep Learning Workloads

contributor:
Ahmad, Afsahi
Electrical and Computer Engineering

subject:
MPI
GPU
Deep Learning
Allreduce
MPI_Allreduce
Message Passing
HPC
High-Performance Computing

abstract:
High-Performance  Computing  (HPC)  refers  to  using  aggregate  compute  power  of many small compute nodes to solve large complex problems which cannot be computed in a reasonable time on a single computer.  In recent years these HPC clusters have moved towards using accelerators, such as Graphics Processing Units (GPUs), to  offload  computationally  intensive  portions  of  applications.  Distributed  Deep Learning workloads on these heterogeneous HPC systems has become increasingly important.  These new workloads have been developed upon existing HPC libraries such as the Message Passing Interface (MPI) and Compute Unified Device Architecture (CUDA).

MPI communication is critical to distributed Deep Learning applications at scale as they place a large amount of pressure on the communication subsystem of HPC clusters.  Improving the MPI communication run-time could benefit Deep Learning. For  that,  we  first  investigate  the  characteristics  of  Deep  Learning  applications  to understand how we can propose and design communication mechanisms which solve some important communication challenges.

We focused on tackling the issues regarding large GPU messages, which we observed  with  Deep  Learning  applications. To  begin  our  investigation,  we  studied NVLink usage within the context of point-to-point communication. Unified Communication X (UCX) framework,  used within the Open MPI library,  only utilises a small portion of the available NVLink bandwidth for intra-socket GPU-to-GPU communication.  We propose a novel GPU-to-GPU data transfer mechanism that stripes the message across multiple intra-socket communication channels and multiple memory regions using multiple GPU streams to utilise all available NVLink paths. Our approach achieves 1.64x and 1.84x higher bandwidth for both UCX and Open MPI + UCX, respectively.

Then  we  propose  a  3-stage  hierarchical,  pipelined MPI_Allreduce design  that incorporates the new multi-path NVLink data transfer mechanism for intra-socket communication  in  the  first  and  third  stages  of  the  collective,  and  PCIe  and  X-bus channels for inter-socket GPU-to-GPU communication in the second stage with minimal interference.  For large messages, our proposed algorithm achieves a large speedup.Finally,  we  evaluate  our  proposed MPI_Allreduce for  Deep  Learning  applications such as Horovod + TensorFlow with a range of Deep Learning models.  For Horovod  +  TensorFlow  and  VGG16,  we  observe  up  to  3.42x  speedup  over  other MPI implementations.

abstract: M.A.Sc.


title: Holistic Education: From Dewey to Tokkatsu

contributor:
Fairfield, Paul
Philosophy

subject:
Dewey
Tokkatsu
Tokubetsu
Katsudou
Katsudo
Education
Philosophy
Philosophy of education
Japan
Japanese
Japanese education
John Dewey

abstract: The educational philosophy of John Dewey is used as a conceptual framework through which to analyze the pedagogical goals and practices of the Japanese ‘tokubetsu katsudou’ system of holistic education. The insight into the Japanese system garnered through its philosophical connection to Dewey is then used to elucidate potential limitations to current attempts to adapt Japanese lesson study to western educational contexts. Lesson study, as a teacher-led method of educational reform, provides a strong alternative to the disconnected reform efforts presently employed in the west. However, the application of lesson study in isolation of its vital connections to the wider context of Japanese pedagogical practices threatens to remove from such an application its positive educative force. This paper draws inspiration and insight from recently published English literature from Japanese educational researchers, as well as the author’s experience teaching in Japanese elementary and junior high school between 2018 and 2020.

abstract: M.A.


title: Developing a Measure for Classification, Differentiation, and Diagnosis of Persistent Genital Arousal Disorder/Genitopelvic Dysesthesia and Hypersexuality

contributor:
Pukall, Caroline
Psychology

subject: sexual arousal

subject: sexual desire

subject: sexual health

subject: hypersexuality

subject: PGAD/GPD

subject: PGAD

subject: Persistent Genital Arousal Disorder

abstract: Persistent Genital Arousal Disorder/Genitopelvic Dysesthesia (PGAD/GPD) is characterized by persistent, distressing genital sexual arousal sensations in absence of mental sexual arousal and sexual desire (Goldstein et al., 2021; Jackowich et al., 2016; Jackowich, Pink, Gordon, Poirier, & Pukall, 2018a). Symptoms of PGAD/GPD can be reduced by engaging in frequent sexual behaviours (Jackowich et al., 2016; Goldstein et al., 2021), which may sometimes be considered to be “hypersexual” in nature (excessive and out-of-control sexual behaviours, see Finlayson et al., 2001; Rinehart & McCabe, 1997) when encountered in clinical contexts. If clinicians are not aware of PGAD/GPD and do not complete a comprehensive differential diagnostic process, PGAD/GPD can be misdiagnosed as hypersexuality (Anzellotti et al., 2010; Leiblum & Seehuus, 2009; Jackowich et al., 2016), and receiving a misdiagnosis contributes to significant barriers to treatment (Jackowich et al., 2017; Jackowich, Boyer et al., 2020). The present research program aimed to develop a measure capable of accurately distinguishing between these two conditions. Study One used archival data collected as part of a larger study (see Jackowich et al., 2018a and 2018b), in which the Hypersexual Behaviour Inventory (HBI-19) (Reid et al., 2011) was administered to a sample of women with PGAD/GPD symptoms. Exploratory factor analysis suggested a two-factor structure (Coping, Negative Affect). Correlations among HBI-19 items and ratings of PGAD/GPD symptom severity and distress suggested that women with PGAD/GPD symptoms identified with items involving sexual behaviour interfering with their lives, but not with items related to coping with negative emotions through sexual behaviour. Significant positive correlations between the new Coping and Negative Affect factors and anxiety symptoms were observed. In Study Two, results of Study One informed development of the Sexual Arousal, Desire, Activity, and Impulses Questionnaire (SADAIQ). The SADAIQ was administered online to a sample of participants with PGAD/GPD and/or hypersexuality. Exploratory and Confirmatory Factor Analysis were used to evaluate the factor structure of the scale, with a six-factor structure being observed. Results of the present program of research present opportunities for a more accurate diagnostic process and conceptualization of distressing issues related to sexual arousal.

abstract: M.Sc.


title: Art-Based Rehabilitation Training (ART) for Upper Limb Sensorimotor Recovery Post Stroke: A 2-Phase Pilot Study

contributor:
Scott, Stephen
Neuroscience Studies

subject:
Upper limb
Art
Stroke
rehabilitation
Pilot study
Kinarm
Feasibility study
Intervention

abstract:
High repetitions of task-oriented practice are essential to drive functional recovery of the upper limb (UL) after stroke. Unfortunately, therapy time focused on the upper limb is limited and movement repetitions are low in standard care stroke rehabilitation. Art-based Rehabilitation Training (ART) is a motor training program designed to augment UL functional recovery by engaging stroke survivors in intense, progressive, structured art-based activities delivered outside of conventional therapy sessions. The objectives of this study were to assess the feasibility of delivering ART in an inpatient setting, collecting clinical and robotic-based measures of sensorimotor function, and quantifying UL use during ART sessions. This study was conducted in two phases: Phase Ⅰ and Phase Ⅱ.

 A convenience sample of patients admitted to a stroke rehabilitation unit with UL motor impairment (n=38) were enrolled in the ART program. The program included 9 sessions of supervised tracing and free-hand drawing tasks completed with both hands, intended to be delivered over a 3-week duration. Feasibility outcomes included ART program adherence, acceptability, safety, and outcome assessment completion. Sensorimotor function was assessed using the Kinarm robot and clinical measures recorded at baseline (pre-ART) and 3-4 weeks follow up (post-ART). Activity intensity was quantified as session time and UL movement time measured by forearm-mounted accelerometers in Phase Ⅱ.

A total of 32 (84%) participants completed the ART program within the intended time frame, and 30 were included in the study analysis from Phase Ⅰ and Ⅱ. Task completion rates ranged from 57-100%. Acceptability was high and few adverse events occurred during the intervention. Kinarm and clinical measures were feasible to collect at baseline and follow up with low rates of attrition. ART session duration, recorded from a subset of 13 Phase Ⅱ participants (77 sessions), yielded a median [IQR] session time of 44 [35-53.5] minutes. In-session UL movement time recorded from 6 participants ranged from 15.2-48.1 minutes.

The ART program was feasible to implement, acceptable to patients, and resulted in augmented UL activity in patients undergoing stroke rehabilitation. Further research is warranted to explore the impact of this program on sensorimotor function and UL use.

abstract: M.Sc.


title: SPR STUDIES OF N-HETEROCYCLIC CARBENE ADSORPTION KINETICS AND THE APPLICATION OF FIBER FABRY-PÉROT CAVITIES IN CHEMISTRY

contributor:
Loock, Hans-Peter
Escobedo, Carlos
Chemistry

subject:
self assembly
self-assembled monolayer
self-assembling monolayer
gold
N-heterocyclic carbene
kinetics
adsorption kinetics
fiber fabry-perot cavity
photonic wineglass
cantilever
viscometer
strain sensor
electrochemical reductive desorption
surface plasmon resonance
spr
monolayer
surface chemistry
photoacoustic spectroscopy
sensor
biosensor
microfluidics
NHC
surface functionalization

abstract:
Thiol self-assembling monolayers (SAMs) on metal surfaces are a key component of many optical biosensors. The discovery that N-heterocyclic carbenes (NHC) form higher-stability SAMs has sparked a wave of exploratory studies and applications. There are still many unknowns surrounding NHC SAM formation, including the adsorption kinetics and overall mechanism.
A lab-built surface plasmon resonance (SPR) spectrometer was used to measure the NHC – gold adsorption kinetics of three NHC species. The spectrometer is described in Chapter 3. Solutions were introduced to a prism-mounted gold film via PDMS microfluidics. A camera then collected reflected light from the prism over a range of angles. At one angle (θSPR), the reflected light intensity was the dimmest. θSPR changes with the surface refractive index and was collected over time.
In Chapter 4, the SAM formation rate constants for three (diisopropyl)benzimidazolium NHCs in methanol are presented and compared. When introduced in a similar way, bicarbonate NHC salts formed monolayers faster than triflate salts.
In Chapter 5, several electrochemical methods are explored to remove NHCs from gold. Desorption efficacy was tested using cyclic voltammetry and X-ray photoelectron spectroscopy. Applying reductive potentials in base led to significant NHC desorption. Oxidative potentials also led to limited NHC desorption via surface corrosion. A prototypical SPR-electrode chip was also presented and tested.
Fiber Fabry-Perot (FFP) cavities are optical strain sensors that work by locking to a cavity resonance fringe. In Chapter 6, an FFP is used to measure dye concentrations by way of photoacoustic spectroscopy. A wineglass is used as the sample holder and acoustic resonator, with the FFP attached to its rim. A modulated laser excites the dye solution, generating an acoustic wave that is amplified by the wineglass and detected by the FFP. Both methyl red and (phospho)molybdenum blue were quantified using the technique.
In Chapter 7, the same FFP cavity was used for in-line viscosity and density measurements using an attached vibrating cantilever. While immersed in liquid, the cantilever’s resonance peak shape was collected and used to infer the liquid’s viscosity and density. The technique was demonstrated for several consumer beverages.

abstract: PhD


title: Deletion, Mutation, and Biochemical Analyses of the Ice Nucleation Protein from Pseudomonas borealis

subject:
Bacterial ice nucleation
Ice nucleation protein
Structure-function relationship
Gram-negative bacteria
Membrane-bound protein
Structural models
Antifreeze protein

abstract:
Outer membrane-associated ice nucleation proteins (INPs) in certain Gram-negative bacteria can cause frost damage to plants by nucleating ice in supercooled water. The INP central domain consists of ~55-80 tandem sixteen-residue repeats that are flanked by short N- and C-terminal domains. Structural models suggest that INP repeats resemble a much larger version of some beta-solenoid antifreeze proteins. Whereas antifreeze proteins organize ice-like water molecules to facilitate ice adsorption, the larger INPs likely order sufficient water molecules to initiate ice nucleation. When Pseudomonas borealis INP (PbINP) was expressed in Escherichia coli, it triggered ice nucleation at high sub-zero temperatures within 2 °C of P. borealis activity. Deletions within the central 65-repeat region lowered ice nucleation temperatures in droplet freezing assays, with sharp decreases below 24 remaining repeats and with 13-15 repeats required for INP activity, including some closest to the C-terminal domain. Nanoliter-sized droplets containing a few E. coli showed uniform freezing at a temperature comparable to freezing by thousands of cells; similar dilutions with P. borealis revealed that 0.5-1% of cells are more active. Mutation of subsets of putative water-organizing and dimerization residues caused decreases in ice nucleation activity that were larger than when the corresponding segment was deleted. This importance of central domain continuity was supported by two different mRuby2 insertions, which also demonstrated functional protein insertion within the repetitive domain. These data show the correlation between central domain length and INP activity and support the hypothesis that repetitive water-ordering motifs in INPs are necessary for potent ice nucleation.
N-terminal domain truncations of PbINP caused only 1-2 °C decreases in freezing temperatures, as seen with deletions on a P. syringae INP. Through truncation of the first 18 residues, INPs are retained in the cytoplasm; a construct of cytoplasmic PbINP with 18 repeats and a polyhistidine tag was produced in E. coli and purified. It appeared to form a heterogeneous aggregate that induced freezing near -11 °C. Heterologous PbINP in E. coli showed strong reactivity with anti-INP, yet weak reactivity was observed with P. borealis lysate. These miscellaneous results serve as points of departure for future experiments.

abstract: M.Sc.


title: Exploring Pulsed Eddy Current (PEC) Responses in Ferromagnetic Cylindrical Structures

contributor: Physics, Engineering Physics and Astronomy

subject:
pulsed eddy current
PEC
non-destructive testing
non-destructive examination
pipes
rebar
insulation
concrete
corrosion detection

abstract:
Corrosion of carbon steel pipes under insulation has a direct negative impact on the structural integrity of the pipe. Insulation prevents visual inspection of external wall corrosion. Long-time decay, up to 0.1 s, in the transient response of Pulsed Eddy Current (PEC), was examined. The transient response of a coaxial solenoidal drive-receive coil pair, oriented parallel to the longitudinal axis, was analyzed over a range of distances from the pipe (liftoff) and wall thicknesses. The single exponential long-time decay constant was dependent on liftoff, simulating a seemingly thicker pipe wall as liftoff increased. At constant liftoff, an inverse-square power law relationship of the long-time decay slope to wall thickness was observed. Pipe with non-concentric wall thickness variation provided an example of partial-circumference corrosion, which the probe was sensitive to. The decay constant increased with liftoff, except at the thickest part of a non-concentric pipe. The most significant conclusion is derived from comparing long-time decay slope with averaged neighbouring wall thicknesses. Averaging of wall thicknesses ±45o (selected window size) from probe location brings all data sets closer to an expected inverse-square relationship, when compared to the purely beneath-probe thickness. This window increases with liftoff, describing the changes in decay constant as interaction with more and more material, unless at the thickest location of a non-concentric pipe.
Characterization of corroded rebar has important implications for evaluating the integrity of concrete structures. PEC measurements on rebar of varying diameter demonstrated that the long-time decay constant exhibited a power law relationship with rebar radius, in agreement with theory. Intercept of the linearly fitted long-time decay underwent an exponential decay as liftoff increased but showed a separable dependence on rebar diameter. In actual concrete structures, rebar is overlaid orthogonally to provide tensile strength in two mutually orthogonal directions. Altering probe angle with respect to the axis of a single rebar presented an intercept that decreased linearly as sine of the probe angle reached 1 (90).  Response to two orthogonal rebar demonstrated a superposition of independent rebar signals at later times in the transient decay. These observed trends indicate use of PEC to characterize rebar.

abstract: M.A.Sc.


title: Knowledge Mobilization and Research Impact in Canadian Universities: A Developmental Evaluation of Network Learning

contributor:
Cooper, Amanda
Education

subject:
Knowledge Mobilization
Research impact
Developmental evaluation
Network Learning
Higher education institutions
Universities

abstract:
In Canada and abroad, governments and research funders are increasing expectations that researchers engage in knowledge mobilization (KMb) efforts to advance the impacts of research. However, despite this growing pressure, researchers and universities are struggling to build their KMb capacity. This dissertation aims to contribute to the research and practice of KMb by investigating the experiences and perspectives university-embedded professional staff who
operationalize KMb as well as their professional networks that build KMb capacity at scale. Developmental evaluation (DE) provides the overarching design of this study, and the participants were members of Research Impact Canada (RIC).
A multi-manuscript format is used to organize this dissertation reflecting one study with
three phases. The first paper corresponds to Phase I of the DE and presents survey findings from 16 RIC leaders, representing 14 networked universities, about the usefulness and use of network learning to build institutional KMb capacity. The second paper corresponds to Phase II of the DE and presents the findings from semi-structured interviews with 20 key informants from 17 RIC member institutions regarding network learning and how it could be structured to improve the disconnect between KMb theory and practice. The third paper combines the findings from Phases I and II of the DE and merges key insights with practitioner narratives from four experienced RIC members, focusing on how the lessons learned from RIC provide insight into how universities can foster active engagement in KMb. The final paper presents an overview of quantitative measurement tools for the impacts of co-production, which developed in response to an identified problem of practice for KMb professionals.
Collectively, the findings from these papers elucidate the potential of network learning to
build institutional KMb capacity, while acknowledging that such efforts require attention to (a) the diversity of individual and institutional practices; (b) tensions that can simultaneously spell network fragmentation or a generative learning environment; and (c) enduring questions for the field of KMb; and (d) how a necessary complement to KMb efforts will require engaging more openly and critically with psychometric and pragmatic considerations when designing, implementing, and reporting on research impact measurement tools.

abstract: PhD


title: Efficient Process Arrival Pattern Aware Collective Communication for HPC and Deep Learning

contributor:
Afsahi, Ahmad
Electrical and Computer Engineering

subject:
MPI
Collective Communication
Deep Learning Frameworks
MPI_Allreduce
Process Arrival Pattern

abstract:
High-Performance Computing (HPC) is the key to tackle computationally intensive problems such as Deep Learning (DL) and scientific applications.
Message Passing Interface (MPI) is the de facto parallel programming standard that fulfills communication in HPC systems.
MPI collective communication operations involve all processes within a program-defined group of processes and have been used extensively in parallel applications.
Unfortunately, most of the studies attempting to improve the performance of collective operations are based on the premise that all the processes commence the communication simultaneously. However, researchers have shown that imbalanced Process Arrival Pattern (PAP) is ubiquitous in real environments. Therefore, it is important to propose new algorithms that improve the performance of collectives by PAP-awareness.
This thesis presents a complete communication characterization of Horovod as one of the most famous distributed DL frameworks. We provide a thorough study on PAP of the MPI\_Allreduce as the most important collective operation used in Horovod and show that the arrival pattern of MPI processes is indeed imbalanced especially for small messages.
Furthermore, we present various proposals for improving the MPI collective communication performance in the presence of imbalanced PAPs for different message sizes.
We propose an intra-node PAP-aware shared-memory-aware MPI\_Allreduce algorithm for small messages that, based on the arrival time of the processes at each invocation of the collective call, dynamically chooses the leader process. The evaluation results show that our design delivers up to 56\% improvement over native algorithms under different imbalanced PAPs.
We also propose a PAP-aware algorithm capable of dynamically constructing the reduction schedule at each invocation of the collective call based on the arrival order of the processes for intra-node MPI\_Reduce and MPI\_Allreduce collectives with large messages, achieving up to 73\%, and 44\% improvement over the state-of-the-art algorithms, respectively.
Finally, we evaluate the performance of two state-of-the-art cluster-wide MPI\_Allreduce algorithms and introduce a PAP-tolerant cluster-wide allreduce algorithm which imposes less data dependency among processes given its hierarchical nature compared to flat algorithms. This algorithm delivers up to 58\% improvement at the microbenchmark level and an average improvement of 10\% for Horovod DL application over native algorithms.

abstract: M.A.Sc.


title: Educator Acculturation while Living and Working Overseas: Stories from Seventeen Sojourning Teachers and School Leaders at International Schools

contributor:
Kutsyuruba, Benjamin
Education

subject: Acculturation

subject: Culture shock

subject: Culturally responsive leadership and teaching

subject: International education

subject: International schools

subject: K-12 education

subject: Leadership, adaptive, and self-leadership

subject: Narrative inquiry

subject: Onboarding and mentoring

subject: Organizational behaviour

subject: Policyscapes

subject: Positive organizational scholarship

subject: Sojourners

subject: Student advocacy

subject: Teaching internationally

abstract: The demand for teachers overseas far outweighs the supply. International school teachers, counselors, and leaders—collectively referred to as educators—become sojourners, living between home and host cultures, which brings both opportunities and challenges, but how do they manage to thrive once in their host country? Policyscapes, metaphorical pools of diverse policies and pedagogies, and culture shock present ubiquitous challenges for sojourning educators. This study explored factors that affect educator thriving overseas in the context of acculturation. To date, the body of research on educators’ acculturation experiences overseas is scarce. Psychological acculturation theories have covered many sojourner groups, but not educators, which is significant because educators are responsible for students, many of whom are also acculturating while attending international schools. This narrative qualitative study followed seventeen participants who were Anglo-Western-certified teachers and educational leaders, working at international schools. The seventeen sojourning educators were living and working in Macau, mainland China, Malaysia, Singapore, and Thailand, and did not identify as belonging to that host culture. The study used the following instruments: field logs, interviews, reflex journals, photovoice, and memory box. Findings provided data about the lived experiences of sojourning educators, namely: sojourning experiences linked with one’s personal identity exploration; effective self-leadership strategies used by participants; effective onboarding/induction practices at one school that could be replicated in other international schools; acculturative stress linked with organizational and host cultures, policyscapes, leadership supports as well as being a leader, and the Covid-19 pandemic; and a comparative analysis of the findings with culture shock theory. Implications for theory lay a foundation for an educator acculturation framework. Implications for practice include propositions for educators, for professional learning, and teacher training. Implications for international school policy include the need for multiple stakeholder engagement to better understand and address policyscapes. Reflections on implications for methodology are provided. Finally, the study concludes with implications for further research.

abstract: PhD


title: THE USE OF LIQUID MICROJUNCTIONS AS AN ANALYTICAL TOOL IN BIOLOGICAL SURFACE ANALYSIS

contributor:
Oleschuk, Richard
Chemistry

subject:
microfluidics
analytical chemistry
strawberries
tissue imaging
mass spectrometry
ambient soft ionization
LMJ-SSP
MALDI
ESI
electrospray ionization
Imaging Mass Spectrometry

abstract: Imaging mass spectrometry (IMS) typically requires extensive sample preparation involving formalin fixation, staining, matrix deposition and embedding (e.g. optimum cutting temperature polymer, OCT) to enable microtomy. The sample preparation steps add considerable time to the analysis and risk altering analyte distribution. Herein we investigate the use of liquid microjunctions as a tool in imaging mass spectrometry to mitigate sample handling steps. First, we describe a new liquid tissue stamping method, Poly-Synchronous Surface Extraction (PSSE), that utilizes an omniphobic substrate patterned with hydrophilic surface energy traps, which when wetted with solvent, form a dense microdroplet array. When contacted with a tissue sample, each droplet locally extracts analytes from the tissue surface, which subsequentially can be analyzed with MALDI-MS or ambient ionization-MS techniques (LMJ-SSP). Optimization of the patterned surface (droplet size and spacing) and its comparison to established imaging techniques is examined. The PSSE method showed good alignment with direct analysis and demonstrated potential to increase the speed of ambient MS tissue imaging techniques. Secondly, the different properties associated with liquid microjunction surface sampling probe imaging mass spectrometry were investigated to determine their effect on the overall image quality.  Extraction tests examined the extraction efficiencies of eight different solvents/mixtures. Four of the solvents from the extraction test and one additional mixture were then used as the LMJ-SSP solvent to directly image 10μm thick strawberry slices. After concluding the best imaging solvent (50/50 Water/Methanol), the dependency of sample thickness on signal intensity was investigated. In addition, an absolute quantitative imaging run was conducted using a pseudo internal standard and at external calibration curve. The use of liquid microjunction methods for direct and indirect analysis showed great potential for increasing sensitivity and versatility, while also decreasing sample handing steps.

abstract: M.Sc.


title: Evaluation of Magnetite as an Indicator Mineral for Porphyry Cu Exploration: A Case Study Using Bedrock and Stream Sediments at the Casino Porphyry Cu-Au-Mo Deposit, Yukon, Canada

contributor: Geological Sciences and Geological Engineering

subject:
magnetite
Casino porphyry copper deposit
stream sediments
exploration geochemistry

abstract:
The chemical composition of magnetite recovered from six local streams around the Casino high-grade porphyry Cu-Au-Mo deposit, west-central Yukon, is compared with igneous and magmatic-hydrothermal magnetite recovered from mineralized and unmineralized host rocks at the deposit. The aim is to characterize magmatic-hydrothermal magnetite associated with mineralization to discriminate between igneous and magmatic-hydrothermal magnetite from different sources in local streams as a potential exploration tool.
Linear discriminant analysis of 12 variables (Mg, Al, Ti, V, Mn, Co, Cr, Ni, Cu, Zn, Ga, and Ge) and plots of Ti versus Ni/Cr are used to discriminate between magmatic-hydrothermal magnetite from the potassic alteration zone and igneous magnetite from granodiorite and quartz monzonite hosting the Casino deposit. Magmatic-hydrothermal magnetite with a chemical composition similar to that from the potassic alteration zone at the Casino deposit is identifiable in stream sediments draining the deposit. Detectable Cu in magmatic-hydrothermal magnetite, present in minute inclusions of sulfide minerals or substituted within the crystal lattice, is a strong indicator of Cu mineralization. We show that the chemical compositions of magnetite recovered from stream sediments can be used to explore for porphyry systems in Canada.

abstract: M.Sc.


title: Path Following using Frequency Modulated Continuous Wave millimetre-wave Automotive Radar

contributor:
Hashtrudi-Zaad, Keyvan
Marshall, Joshua
Electrical and Computer Engineering

subject:
Radar
mmWave
Localization
Autonomous Vehicle
FMCW
Machine Learning
GRU

abstract:
This thesis presents the discovery, methodology, and experimental validation of a
path planning algorithm developed to only use Frequency Modulated Continuous Wave (FMCW) radar. Radar has shown to be semi-invariant to inclement weather such as snow, fog, extremely lighting conditions, and heavy rain. Traditionally, autonomous vehicle (AV) path planning algorithms use multiple introceptive and exteroceptive sensors to first determine the current position of the vehicle, then plan a path based on that position. These sensors include LiDAR, GNSS, cameras, inertial measurement units, ultrasonic, and radar. In previous research, the use of radar in these systems is to aid with the detection of obstacles, which could then be used to determine paths, not as a single modality system. This thesis presents research into using FMCW automotive radar with the aid of radar retro-reflectors to test the viability of a single modality path planning algorithm. The result is an efficient, Gated Recurrent Unit (GRU) deep neural network that has been trained on custom synthetically trained data of a vehicle following a path of retro-reflectors.
The GRU network was then experimentally validated using a  60 kg skid-steer robot showing promising path planning results while in heavy fog. The results showed an average accuracy of 0.30 ± 0.15 m. When compared to LiDAR during the same testing conditions, the visual based sensor was unable to produce a viable path. As a result, this system satisfies the requirement for centimetre level accuracy for Level 3 autonomous driving in inclement weather.

abstract: M.A.Sc.


title: Exploration of the Mechanism of Action of Human Oviduct-Specific Glycoprotein (OVGP1) in Regulating Sperm Capacitation

contributor:
Kan, Frederick
Biomedical and Molecular Sciences

subject:
Oviductal Secretions
OVGP1
Sperm Capacitation
Tyrosine Phosphorylation
Intracellular Calcium

abstract: The present research is of significance to the field of fertility treatment as better understanding the mechanism that regulates the function of oviduct-specific glycoprotein (OVGP1) could lead to its supplementation to culture medium used in assisted reproductive technologies, potentially improving the fertilizing competence of sperm. The mammalian oviductal non-ciliated secretory cells synthesize and secrete a major glycoprotein known as oviductin or OVGP1. Various mammalian in vitro studies have implicated native OVGP1 in enhancing sperm capacitation, sperm motility, sperm penetration and sperm-egg binding. Our laboratory has successfully produced recombinant human OVGP1 (rHuOVGP1) which has been shown to enhance tyrosine phosphorylation of sperm proteins, a biochemical hallmark of capacitation that takes place in the sperm tail, enhance the potential of sperm undergoing acrosome reaction, and increase sperm-egg binding. In the present study, we set out to explore the mechanism of human OVGP1 in enhancing key events of sperm capacitation. A major mechanism of inducing sperm capacitation is through the increase of intracellular calcium concentration ([Ca2+]i). The cation channels of sperm (CatSper) have been found to control the entry of Ca2+ ions into the sperm tail during capacitation and to be required for male fertility. Progesterone (P4) is known to bind to the plasma membrane P4 receptor of sperm and activate the CatSper channels, thus inducing the influx of Ca2+. We hypothesized that human OVGP1 enhances tyrosine phosphorylation of sperm proteins through increasing [Ca2+]i, similar to P4, via the CatSper channels during human sperm capacitation. Results showed that the presence of rHuOVGP1 in the capacitating medium was able to further increase the level of [Ca2+]i in human sperm. Additionally, treatment of sperm with rHuOVGP1 further increases and sustains the level of [Ca2+]i in sperm following treatment with P4. The inhibition of CatSper channels with the selective inhibitor HC-056456 impedes the effects of rHuOVGP1 on [Ca2+]i. Furthermore, the present study showed that P4 alone and in combination with rHuOVGP1 can further enhance the level of sperm protein tyrosine-phosphorylation. In summary, OVGP1 and P4 function most effectively in combination to enhance sperm capacitation through upregulating [Ca2+]i and protein tyrosine-phosphorylation.

abstract: M.Sc.


title: Statistical Mechanics and Design Behaviours in a Network Model of Arrangement

subject:
statistical physics
tensor network
design
distributed system
naval engineering
systems physics
naval architecture
arrangement problem
early stage design

abstract: A key challenge in large scale design is that the process to solve for a design solution is costly and time-consuming. Designers in many situations use an iterative approach in which prototypes are repeatedly created and tested. In large systems however, this process is not practical. Consequently, analysis must be carried out in for early-stage design. Early-stage design is an important problem in large-scale distributed systems. A distributed system is a system which the function of the system is distributed between the elements. A main concern in designing many distributed systems is the arrangement of the design elements. Arrangements determine the effectiveness and efficiency of a design solution. I study arrangement problems in a model distribution system in naval engineering where the system has two types of degrees of freedom: placement and routing. We use extended ensembles in statistical mechanics to analyze a distributed system model drawn from naval architecture. I show that the trade-offs between placement and routing yield four phenomena among probable design solutions. First, I show that design freedom does not necessarily increase with an increase in resources. Instead I show that the trade-offs between the degrees of freedom affect the design freedom, decreasing it in some configurations. Second, I find that logical connections between design elements creates distinct arrangement configurations that depend on connectivity. Third, I find that the correlation between the design elements was characterized by clustering. Fourth, I find that probable placements of the design elements were determined the symmetry of the embedding space, and that perturbing the embedding space could induce large rearrangement. My results demonstrate that design behaviour in a model distributed system is driven by the trade-offs between the placement and routing degrees of freedom. Having multiple types of degrees of freedom is a common feature in complex distributed systems. The results of this thesis suggest that distributed systems with multiple competing types of degrees of freedom will show similar features to the phenomena seen here. The probabilistic behaviour I found also have some analogues to that of conventional physical systems. These analogues reinforce the idea that distributed system designs can be analyzed and understood using physics methods.

abstract: M.Sc.