title: Inorganic riverine freshwater tracers and water mixing identifiers in southeastern Hudson Bay

contributor:
Guéguen, Céline
Brown, Stephen
Chemistry

subject:
freshwater tracer
Ba concentration
Hudson Bay
Sr isotope
mixing model
La Grande River
Great Whale River
CDOM absorption
Salinity
87Sr/86Sr
isotope dilution

abstract: This thesis was designed to investigate the potential use of barium (Ba) concentrations as well as strontium (Sr) concentrations and Sr isotope ratios as freshwater tracers in southeastern Hudson Bay with an emphasis on the Belcher Islands. Ba concentrations ranged from 40 to 672 nM with higher concentrations observed near river mouths in the winters of 2015-2017. This contrasts with Sr concentrations where the higher levels were found offshore (up to 105 µM). Both surface profiles and depth profiles of Ba concentrations in conjunction with coloured/chromophoric dissolved organic matter (CDOM) absorption coefficient and salinity showed clear signs of freshwater mixing in the southeastern side of the Belcher Islands sourced from nearby rivers. A three-endmember Ba mixing model was applied to determine fractions of freshwater, seawater, and sea ice melt at various sites. Based on the fraction of freshwater determined using oxygen isotope ratio, La Grande River was identified as the major source of freshwater to the Belcher Islands whereas the influence of the Great Whale River was found to be only locally important. Sr concentrations were successfully employed to identify mixing between freshwater and seawater when used in conjunction with CDOM absorption coefficients (a[355]) and salinity. 87/86Sr ratios (ranging from 0.7092 in open ocean to 0.7100-0.7340 near river mouth) were also used in a two-endmember model to assess mixing processes.  The predicted 87/86Sr ratios were within 0.002% of the observed ratios in the Nelson, Winisk and Great Whale estuaries. Although the two-member model was less robust around the Belcher Islands, it found that the Great Whale river was not the main contributor in the region, confirming the Ba results. Together these results showed that both Sr and Ba can be used in a complementary fashion to other freshwater tracers (salinity, a[355], δ18O) and make for great tools in modelling freshwater fractions. However, due to their low sensitivity of freshwater detection, they should not be used as a standalone tracer. These tracers used in a complementary fashion can suggest which rivers have the greatest impact to the freshwater environment and ultimately need to be more seriously preserved.

abstract: M.Sc.


title: Stochastic and adaptive processes affect rapid evolution of two invasive plants in North America

contributor:
Colautti, Robert
Biology

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:
Biological Invasion
Evolution
Population Genetics
Herbarium
Phenology
Rapid Adaptation
Ecology
Invasive Species

abstract:
Evolution can occur rapidly on timescales of years to decades. In addition to adaptive responses to natural selection, stochastic processes such as gene flow and genetic drift may influence rapid evolution in many species. Invasive species are good candidates to study rapid evolution because they experience novel selective pressures in their introduced range, as well as founder effects, population bottlenecks, and long-distance dispersal. Consequently, I studied adaptive and stochastic evolution in Lythrum salicaria and Alliaria petiolata – two species that have rapidly expanded their introduced range in North America.

Previous common garden and field studies in Lythrum salicaria showed that invasive populations have locally adapted to their environment, resulting in a latitudinal cline in flowering. To test whether latitudinal clines are replicated in other parts of North America, I analyzed phenological development using herbarium specimens in a ‘virtual common garden’ analysis that controlled for variation in sampling date and local growing conditions. After controlling for time of establishment, I found repeated latitudinal clines in phenology across North America. A non-linear least squares model of phenological development showed phenological curves shift over time, particularly in populations with short growing seasons.

North American populations of Alliaria petiolata reproduce primarily through self-pollination, making it a good system to examine rapid evolution at the genome level. Molecular genetic markers are helpful for reconstructing the history of invasion to account for stochastic processes that may affect evolution during invasion (i.e. colonization, drift, gene flow). I analyzed restriction-site-associated DNA sequences (RAD-Seq) to identify single nucleotide polymorphisms (SNPs) in 95 inbred lines from eastern North America. Analysis of allele balance (i.e. proportion of each SNP at a heterozygote locus) showed that most individuals are likely hexaploid. I compared two variant callers, the diploid gstacks, and freebayes, which can call polyploid genotypes. I found gstacks was biased towards calling homozygote loci compared to freebayes. Lastly, I found significant population structure, despite the short history of this species in North America. Moreover, I found two distinct genetic clusters in eastern North American populations, which suggests at least two separate introductions.

abstract: M.Sc.


title: The Kahnawà:ke Schools’ Diabetes Prevention Project: Perspectives on Data Sovereignty in Indigenous Community-Academic Partnered Health Research

contributor:
Levesque, Lucie
Kinesiology and Health Studies

subject: KSDPP Ethics Governance CBPR OCAP

abstract: Introduction. Data sovereignty in Indigenous research recognizes the authority of Indigenous peoples over research data and processes. Data sovereignty is an important tool for the self-determination of Indigenous communities, as it fosters the collection of relevant data that aligns with community goals and interests. While guidelines exist to support Indigenous community-academic research partnerships in facilitating community-controlled research and data sovereignty, these guidelines often lack practical clarity, and could benefit from practical examples of successful partnerships. Purpose. The purpose of this study is to explore how The Kahnawà:ke Schools’ Diabetes Prevention Project (KSDPP), a mature and successful Indigenous community-academic research partnership, operationalizes data sovereignty and facilitates research in a community-controlled manner. Methods. Eight individuals having various roles within the KSDPP participated in semi-structured interviews. The interview guide was theory-informed using indicators of data sovereignty extracted from literature on data sovereignty in community-controlled research. The KSDPP Code of Research Ethics and letters of information/consent forms from past KSDPP studies were also reviewed. These data were collected and analyzed using a thematic analysis. Results. Seven themes were identified related to research benefits, collaboration and communication, capacity and growth, respectful relationships, data stewardship, defining community control, and growth through adversity. Discussion. The community controls the KSDPP research process and accordingly the content, management, and use of data created. The community values the cooperation and roles played by academic partners and defines control as appropriate and beneficial to their culture and context.

abstract: M.Sc.


contributor:
Ouellette-Kuntz, Helene
Zevin, Boris
Patel, Sunil
Public Health Sciences

subject:
Obesity
Bariatric Surgery
Gastric Bypass
Malnutrition
RYGB
Surgical Complication

abstract:
Background: Severe post-operative malnutrition after bariatric surgery is believed to be very rare, but little is known about its incidence and risk factors. Post-surgical follow-up attendance at a bariatric centre reduces the risk of many bariatric surgery-related complications, but its impact on the occurrence of severe post-operative malnutrition has not been studied.

Aims: 1) Describe incidence and factors associated with severe nutritional complications following bariatric surgery. 2) Investigate the relationship between attending follow-up during the first post-surgical year after Roux-en-Y gastric bypass (RYGB) and severe nutritional complications.

Methods: Retrospective population-based cohort study of Ontario adults undergoing bariatric surgery from 2009 to 2015. The primary outcome was a severe nutritional complication, defined as hospital admission with malnutrition. Patient, institution, and surgical factors were obtained from administrative databases and the Ontario Bariatric Registry (OBR). In the first study, we describe incidence and patterns of severe nutritional complications after bariatric surgery, including association with other post-surgical complications, mortality patterns and healthcare use. In the second study, we examine the relationship between follow-up at a bariatric centre during the first year after surgery, and occurrence of the primary outcome after the first year using Cox Proportional Hazards multivariable modeling in patients who had RYGB and participated in OBR. Datasets were linked and analyzed at ICES Queen’s.

Results: 18,783 Ontario adults underwent bariatric surgery during the study period (88.8% RYGB). Mean age was 45.1 years, 81.8% were female and 57.1% participated in the OBR. 2% of the cohort had severe nutritional complications, with an incidence rate of 4.5 per 1000 person-years of follow-up. Risk was constant over time. Factors associated with severe nutritional complication included more major comorbidities, post-surgical complication, and imperfect follow-up. 9105 patients met inclusion criteria for the second study. Compared to patients with perfect follow-up, those with no follow-up (HR 3.09) and partial follow-up (HR 1.94) had significantly increased risk of severe nutritional complications.

Conclusions: Severe nutritional complications after bariatric surgery occur at rates similar to many bariatric surgery-specific complications. Adherence to follow-up during the first year after RYGB is independently associated with a reduction in risk of subsequent severe nutritional complications.

abstract: M.Sc.


title: New Sensing Techniques for Improved Assessment of Rail Infrastructure

contributor:
Hoult, Neil
Civil Engineering

subject:
Structural Engineering
Rail
Bridge
Monitoring
Fibre Optic Sensors
Distributed Sensors

abstract:
As demand grows for rail transportation, so too does the stress on Canada’s rail infrastructure, and improved monitoring technologies are needed to prevent track failure and assist in the bridge rehabilitation process. Currently, most quantitative methods of stress detection disrupt service traffic and are impractical for widespread implementation. Thus, there exists a need for sensor systems that can facilitate more comprehensive condition assessments of rail infrastructure. This thesis investigates the potential for discrete and distributed strain sensors to fulfill this objective.
	The buckling or breaking of continuous welded rail due to constrained thermal movement leads to derailments and is currently largely undetectable. Thus, there is a requirement for novel sensing tools capable of identifying these issues. In response to this, a series of laboratory tests were performed to assess the ability of two fibre optic sensors (FOS) to measure axial strain in rails under various boundary and environmental conditions. The presence of temperature-induced error on measured strains led to the development of thermal correction factors for each technology and fibre combination tested. The application of these factors in subsequent laboratory and field tests demonstrated their necessity for successful long-term rail monitoring with FOS.
	The combination of discrete and distributed strain sensors have the potential to improve current monitoring techniques for railway bridges. To investigate this, two experimental campaigns were undertaken on a steel railway bridge in North Bay, Canada, with the added intention of investigating longitudinal force transfer and the effect of traction bracing, installed as part of the structure’s rehabilitation. Data from both pre- and post-rehabilitation tests suggested that most axial force in the rail is distributed over its length, rather than being transferred immediately into the superstructure and that the bridge experienced undesirable bi-axial bending. Furthermore, data from the post-rehabilitation tests suggested that the added traction bracing did not affect the behaviour of the bridge. Finally, a full-scale three-dimensional finite element model of the instrumented bridge span was developed to aid in the understanding of the bridge’s behaviour due to both gravity and longitudinal loads.

abstract: M.A.Sc.


title: Connecting environmental exposures with allergic and respiratory outcomes - The ongoing study of the Kingston Allergy Birth Cohort

contributor:
Ellis, Anne
Biomedical and Molecular Sciences

subject: Allergy

subject: Asthma

subject: Developmental origins of health and disease

subject: Umbilical cord blood

subject: T helper cells

subject: Regulatory T cells

subject: Atopy

subject: Indoor air pollution

subject: Outdoor air pollution

subject: FOXP3

subject: Prenatal exposure

subject: Postnatal exposure

abstract:
Atopic diseases like allergies and asthma are mediated by several types of immune cells such as Regulatory T cells (Treg), and T helper type 1, 2, and 17 (Th1, Th2, and Th17) cells. Reductions in Treg numbers and the Th1:Th2 ratio and increases in Th17 cells have been related to atopic disease pathogenesis; however, whether these are a cause or result of disease remains unclear. Moreover, researchers have identified several early life environmental exposures that contribute to allergic disease development. However, these is a lack in understanding of how these exposures relate to changes at the cellular and genetic level, and how these exposures contribute to atopic disease progression.
We polarized T helper cells from umbilical cord blood mononuclear cell (CBMC) samples from children with high (n=3) and low (n=4) atopic risk. We gathered information on the home environment of 92 mother child pairs, determined the odds ratio (OR) of a positive SPT (SPT) at 2 years with exposure to indoor air pollutants, and compared the number of different exposures between SPT positive and negative at 2 years. Lastly, we attained prenatal and current exposure data to air pollutants of 39 mother child pairs at 6 to 7 years of age and collected a blood samples from the 24 children. We determined the relationships between exposure to air pollutants with sensitization, cough/wheeze, plasma cytokine levels, Treg and Th17 frequencies, and FOXP3 expression.
	High atopic risk CBMC samples had higher Th17 frequencies following T cell polarization. The OR of a positive SPT at 2 years was increased with exposure to candles, cats, and environmental tobacco smoke. 2 year old children with a positive SPT had more exposures at each time point than children with a negative SPT. Children with atopic disease at 6 to7 years had reductions in the regulatory/inflammatory cytokine ratios and children with exposures to cats and high levels of indoor air pollutants had lower plasma cytokine levels. FOXP3 expression was elevated in atopic children and in children with exposure to air pollution.
	This work provides evidence supporting the importance of the early life environment to atopic disease development.

abstract: M.Sc.


title: Accelerated Convergence of Saddle-Point Dynamics

contributor:
Gharesifard, Bahman
Mathematics and Statistics

subject: Optimization Controls Saddle-points

abstract: In this thesis, a second-order continuous-time saddle-point dynamics is introduced that mimics Nesterov's accelerated gradient flow dynamics. We study the convergence properties of this dynamics using a family of time-varying Lyapunov functions. In particular, we study the convergence rate of the dynamics for classes of strongly convex-strongly concave functions. For a class of quadratic strongly convex-strongly concave functions and under appropriate assumptions, this dynamics achieves global asymptotic convergence; in fact, further conditions lead to an accelerated convergence rate.  We also provide conditions for both local asymptotic convergence and local accelerated convergence of general strongly convex-strongly concave functions.

abstract: M.A.Sc.


title: Functional Nitroxyls for Polypropylene Modification

contributor:
Parent, J. Scott
Chemical Engineering

rights: Attribution-NonCommercial-ShareAlike 3.0 United States

subject:
Polypropylene
Long-Chain Branching
Radical Modification
Functional Nitroxyls
Maleic Anhydride
Polymer Functionalization

abstract:
Chemistry for introducing a long-chain branch (LCB) architecture to linear, isotactic polypropylene (PP) is described, wherein degradation of the polymer matrix through β-scission of macroradicals is inhibited by an additive comprised of a nitroxyl that bears a polymerizable functional group. Trapping of alkyl macroradicals by the nitroxyl yields a macromonomer derivative that crosslinks when exposed to residual initiator-derived radicals. As such, formulations containing 4-acryloyloxy-2,2,6,6,-tetramethylpiperidine-1-oxyl (AOTEMPO) and a peroxide transform linear PP into a gel-free, long-chain branched derivative (LCB-PP) that exhibits exceptional strain hardening with minimal loss in matrix molecular weight.

The chemistry is extended to produce PP bearing pendant anhydride and/or imide grafts. Formulations containing 4-vinyl ether-2,2,6,6-tetramethylpiperidine-1-oxyl (VETEMPO), maleic anhydride (MA), and peroxide produced anhydride-functionalized polypropylene (PP-g-MA). Following macroradical trapping by VETEMPO, pendant vinyl ether groups undergo a strictly alternating copolymerization with MA, thereby introducing anhydride without incurring large-scale matrix degradation. At a given melt viscosity, this technology provided PP-g-MA derivatives with higher graft content than standard peroxide-only reactions. Moreover, when combined with the difunctional monomer N,N’-1,3-phenylene-dimaleimide (PDM), VETEMPO enabled the production of highly crosslinked PP with an appreciable gel fraction.

abstract: M.A.Sc.


title: "Even Peacekeepers Expect Something in Return": An Exploratory Epidemiological Analysis of Sexual Interactions between UN Peacekeepers and Haitian Females

contributor:
Bartels, Susan
Stuart, Heather
Public Health Sciences

subject:
Epidemiology
Peacekeeping
United Nations
Gender
Transactional sex
Sexual Abuse and Exploitation

abstract:
Background: In 2004, the UN sanctioned The United Nations Stabilization Mission in Haiti (MINUSTAH) to address Haiti's political instability. Reports of sexual misconduct perpetrated by peacekeeping personnel, including children fathered by peacekeepers, were made during the course of MINUSTAH. To date no epidemiological studies have analyzed the distribution and determinants of civilian-peacekeeper sexual interactions.

Objectives: (1) Analyze gender differences among perceptions of civilian-peacekeeper sexual interactions; (2) Explore the association between location (rural, semi-urban, urban) and the presence of narratives about civilian-peacekeeper sexual interactions; (3) Investigate the relationship between narratives of civilian-peacekeeper sexual interactions and the willingness to engage with the UN.

Methods: In 2017, a cross-sectional survey was administered by Haitian research assistants using SenseMaker®, a rapid mixed-methods data collection tool that allows participants to share a narrative on a topic of interest. In total, 2541 self-interpreted narratives pertaining to the experiences of women/girls in relation to the UN were collected across Haiti. Secondary data analysis using log-binomial regression modeled the relationships of interest. Statistical analysis was performed using SAS 9.4.

Results: (1) Compared to males, female Haitians were more likely to perceive civilian-peacekeeper sexual interactions as relationships and to perceive the peacekeeper as wealthy and able to provide support. (2) After adjustment, Haitians living in rural areas were more likely (RRrural: 1.19; 95% CI: 1.03, 1.38) to share a narrative about sexual interactions with peacekeepers, compared to Haitians living in urban areas. (3) The association between narratives of civilian-peacekeeper sexual interactions and the willingness to engage with the UN was modified by who the narrative was about. Haitians who expressed personal experiences of sexual interactions were more likely (RRsex: 4.52; 95% CI: 3.34, 6.12) to reject the UN/MINUSTAH, compared to Haitians who shared personal positive/neutral narratives of MINUSTAH.

Conclusion: Narratives of civilian-peacekeeper sexual interactions were perceived differently by men and women, geographically distributed, and associated with rejecting the UN/MINUSTAH. This epidemiological analysis is an empirical steppingstone to understanding the distribution and determinants of civilian-peacekeeper sexual interactions.

abstract: M.Sc.


title: Using Population Genomics to Disentangle the Evolutionary History and Aid Conservation of the Leach’s Storm-Petrel Species Complex (Hydrobates spp.)

contributor:
Friesen, Vicki
Biology

subject:
Population Genomics
Phylogenetics
Conservation
Speciation

abstract: Despite their ability to overcome most geographic barriers to dispersal and to fly long distances, many seabird species exhibit strong population genetic structure. For this project, I quantify population differentiation within a pelagic seabird, the Leach’s storm-petrel species complex (Hydrobates spp.). This species complex covers a wide geographic range in the northern Atlantic and Pacific, comprising three species (H. leucorhous, H. socorroensis, and H. cheimomnestes) and two subspecies (H. l. leucorhous and H. l. chapmani). Hydrobates socorroensis and H. cheimomnestes both breed on Guadalupe Island in the Pacific, and may have undergone a form of sympatric speciation known as allochronic speciation, or speciation via differences in breeding time. As species classifications for the Leach’s storm-petrel are only based on phenotypic distinctions, further genomic work is needed to elucidate processes driving their diversification. Using double-digest restriction site-associated DNA sequencing of 141 individual Leach’s storm-petrels from 13 breeding populations throughout the species’ ranges, I identify five genetically differentiated groups, although some gene flow may still occur between subspecies and between populations separated by ocean basins. Allochronic sister taxa, H. cheimomnestes and H. socorroensis, are highly differentiated from all other populations, as is a common pattern for populations of other organisms residing on Guadalupe Island. I discovered that the Guadalupe populations first diverged from all other H. leucorhous, and then diverged from one another, supporting allochronic divergence as a viable mode of speciation. I also discovered that H. l. chapmani in the south Pacific genetically diverged from H. l. leucorhous in the north Pacific before Pacific and Atlantic H. l. leucorhous diverged, suggesting either parapatric speciation along a genetic cline, or non-geographic barriers to gene flow between north and south populations. Finally, I found 12 putatively adaptive loci possibly implicated in either local adaptation or conserved selection pressures across populations. Overall, the Leach’s storm-petrel species complex has a complicated evolutionary history, influenced by both geographical and non-geographical barriers to gene flow. My thesis also provides a framework for classifying species versus subspecies, and how these classifications can be used for conservation management.

abstract: M.Sc.


title: The Role of Fucosylation in a Three-Dimensional Multicellular Tumor Spheroid Model of Prostate Cancer

contributor:
Szewczuk, Myron
Biomedical and Molecular Sciences

subject:
Prostate Cancer
Multicellular Tumor Spheroids
Machine Learning
Image Object Detection
YOLO
Fucosylation
Three-dimensional culture

abstract: Multicellular tumor spheroids are a three-dimensional model of cancer with a variety of applications. Spheroids are the preferred preclinical model in drug screening because they recapitulate the tumor microenvironment. Gaining a better understanding of how spheroids form can provide insights into tumor formation in patients, which can ultimately lead to uncovering additional therapeutic targets. However, the analysis of spheroids can be challenging. Developing a more precise definition of a spheroid and automating analysis can reduce human error, save time, and improve the accuracy of results. Previously, we have shown that spheroids measuring at least 60µm can be generated from DU145 prostate cancer cells using cyclic Arg-Gly-Asp-D-Phe-Lys peptide modified with 4-carboxybutyl-triphenylphosphonium bromide, or cRGDfK(TPP). We showed that sialylation, a post-translational modification involving the attachment of sialic acids to glycoproteins, facilitates the formation of spheroids generated with cRGDfK(TPP). Here, the role of a closely related glycosylation event called fucosylation was investigated in spheroid formation. It was found that DU145 cells expressed higher cell-sruface alpha-1,6- compared to alpha-1,2-fucose. Only blockade of the alpha-1,6-fucose linkage with Aspergillus oryzae lectin (AOL) prior to the addition of cRGDfK(TPP) to monolayer prostate cancer cells resulted in a statistically significant reduction in prostasphere volume on day five following treatment. Moreover, two improvements to the spheroid model were implemented: a statistically-supported minimum spheroid diameter of 40µm and an automated image object detection system. Using 40µm as the diameter threshold confirmed the role of alpha-1,6 fucosylation in reducing spheroid volume on day five following treatment with AOL. Finally, a state-of-the-art, image object detection system called You Only Look Once version 2 (YOLOv2) was used to automate the analysis of 156 prostaspheres. Preliminary results showed that YOLOv2 corroborated manual MCTS detection and volume estimations with high precision and acceptable accuracy. Refining the definition of a spheroid and implementing YOLOv2 are important improvements to our spheroid model, helping in the study of the role of fucosylation in spheroid formation. The optimization of the MCTS model can ultimately expedite the drug discovery process.

abstract: M.Sc.


title: Exploring the Alignment of the Secondary School Certificate English Examination with Curriculum and Classroom Instruction: a Washback Study in Bangladesh

contributor:
Cheng, Liying
Education

rights: Attribution-NonCommercial-NoDerivs 3.0 United States

subject: Washback

subject: ESL

subject: EFL

subject: Influence of Examinations

subject: Test Impact

subject: Curriculum Alignment

subject: Teaching and Learning of English

subject: Bangladesh

subject: South Asia

subject: Qualitative Research

abstract:
In the nearly three decades of research, washback research has explored a range of factors such as teachers, students, and social contexts in order to understand how testing influences teaching and learning globally.  However, little research has been done on how (mis)aligned assessment systems may create test washback on classroom teaching and learning.  In South Asian contexts, test washback is especially noticeable due to the region’s extremely examination-oriented education system, yet studies on washback in this part of the world are extremely limited especially in Bangladesh.  This doctoral dissertation attempted to bridge this gap in the literature by investigating the alignment of curriculum, textbook, and examination in Bangladesh to examine how alignment or misalignment relationships created washback effects on classroom teaching and learning. The Secondary School Certificate (SSC) examination is the most high-stakes examination in Bangladesh.  Approximately two million students take the SSC examination each year.  High scores on this examination, particularly SSC English-language scores, are needed to gain admission to higher education and top universities; high SSC scores can also help students obtain better jobs.  Also, getting a better grade in the English subject is a badge of status marker for students and their parents. Thus, securing the highest possible score on the SSC English examination is essential for test takers.  To explore how the SSC English examination influenced English classroom teaching and learning, this study used a multimethod, qualitative approach.
Drawing on an adapted argument and evidence-based validation framework (Pellegrino et al., 2016), I collected evidence from multiple stakeholders to build the instructional validity of the classroom instruction. Instructional validity seeks evidence about the alignment of examination with the defined knowledge and skills in the curriculum, and how examination guides classroom teaching and learning (Pellegrino et al., 2016). Data were collected through documents, interviews, classroom observations, and focus groups.  Three main findings of the study highlight the complex and non-linear nature of washback in the context of Bangladesh.  First, the SSC English examination was largely misaligned with the national English curriculum and the prescribed textbook because of bureaucratic and contextual problems in the country’s educational system.  Second, because of this misalignment, teachers taught to the test rather than the curriculum.  Since high SSC English examination scores were the most highly valued outcome, English skills not on the examination were ignored by teachers.  Third, students prepared only for the examination, fulfilling their short-term goal of high SSC English scores while neglecting their long-term goal of improving English proficiency. While students took intense test preparation, they were privy to the fact that test preparation was not going to improve their English skills. For national curriculum and textbook developers, these washback effects were unintended.  However, for teachers and students, these results were intentional and what they wanted, as students and teachers prioritized high SSC examination scores over English proficiency which was the original goal in the English curriculum.

abstract: PhD


title: Clinical Symptoms And Biomarkers Of Bermuda Grass-Induced Allergic Rhinitis Using The Nasal Allergen Challenge Model

subject:
Allergy
Allergic Rhinitis
Allergen specific IgE
Bermuda grass pollen
Biomarkers
Eosinophils
IL-33
Nasal Allergen Challenge
Nasal Lavage
Peak Nasal Inspiratory Flow
Total Nasal Symptom Score

abstract: Bermuda grass pollen is a prevalent allergen that flourishes in subtropical climates, such as the southern United States. Bermuda grass exposure is traditionally believed to be relatively low in Ontario due to the colder environment. However, high rates of Bermuda grass sensitization have been observed in Kingston. We sought to investigate whether Bermuda grass pollen extract can provoke allergic rhinitis (AR) symptoms in sensitized participants. We also examined if the nasal allergen challenge (NAC) model is appropriate to study Bermuda grass-induced AR and biomarkers in allergic participants from south eastern Ontario. Twenty-one Bermuda grass sensitized and 12 non-allergic consenting participants successfully completed a titrated nasal challenge with increasing concentrations of Bermuda grass allergens. Total nasal symptom score (TNSS) and peak nasal inspiratory flow (PNIF) were collected before allergen exposure and 10 minutes after the delivery of each concentration. Twelve allergic participants that met the qualifying criteria (TNSS≥8 and PNIF fall≥50%) and 11 non-allergic controls returned for a single dose NAC. Peripheral blood, nasal lavage, and nasal tissue were collected before and after NAC to investigate AR biomarkers. The mean Bermuda grass wheal size was significantly greater in sensitized participants compared to healthy controls (sensitized=6.7mm, non-allergic=0.0mm). Nineteen out of 21 sensitized participants met the criteria of a clearly positive allergic response when Bermuda grass allergen was administered to the nasal cavity. During the NAC visit, Bermuda grass allergic participants had significantly greater TNSS between 15 minutes and 3 hours post NAC compared to non-allergic controls. Bermuda grass sIgE was significantly increased in allergic participants when comparing screening to NAC visits (screening=3.46 kUA/l, baseline=9.16 kUA/l, 6 hours=8.86 kUA/l). Likewise, allergic participants significantly increased in the percentage of nasal eosinophils at both 1 and 6 hours post NAC. Mean concentration of peripheral leukocytes (baseline=5.48x109/l, 6 hours=6.63x109/l), neutrophils (baseline=3.23x109/l, 6 hours=3.89x109/l), and lymphocytes (baseline=1.64x109/l, 6 hours=2.07x109/l) were significantly increased 6 hours post NAC in Bermuda grass allergic participants. Although Bermuda grass pollen is a non-native allergen in Ontario, Bermuda grass extract can induce AR symptoms in sensitized participants during allergen challenge. The NAC model is appropriate to study Bermuda grass-induced AR and associated biomarkers.

abstract: M.Sc.


title: Biopsychosocial Predictors of Suicide Risk in Inflammatory Bowel Disease

contributor:
Tripp, Dean
Psychology

subject:
Inflammatory Bowel Disease
suicide risk

abstract: Inflammatory Bowel Disease (IBD) is a debilitating chronic medical condition affecting millions of people worldwide. Epidemiological data suggest suicidal behaviour is a persistent concern in IBD populations, but little research examines suicide risk (i.e., ideation and attempts) in this population. This study examined how patient history, biomedical, psychosocial, and theory-driven predictors of suicidal behaviour interact to predict suicide risk in individuals with IBD. Consenting participants completed two online self-report surveys one month apart (NTime 1 = 324, NTime 2 = 147). Based on SBQ-R clinical cut-off scores, over 30% of individuals in this sample were at-risk for suicide. Hierarchical regression analyses (N = 285) explained 48% of the variance in suicide risk, with theory-driven variables (i.e., psychache, perceived burdensomeness and thwarted belongingness from the Interpersonal Theory of Suicide) emerging as the strongest predictors. A parallel mediation (N = 324) revealed that psychache and perceived burdensomeness, but not thwarted belongingness, mediated the relationship between IBD symptoms and suicide risk. A cross-sectional model of the progression of IBD symptomatology to suicide risk was also examined (N = 282). Biomedical variables (i.e., IBD symptoms, average pain) predicted distal mental experiences of suicidal behaviour (i.e., shame, depressive symptoms, hopelessness), which predicted proximal mental experiences of suicidal behaviour (i.e., psychache, perceived burdensomeness), which then predicted suicide risk. The final analysis examined the ability of baseline biopsychosocial variables to predict suicide risk one month into the future (N = 128). Baseline variables were similarly associated in the longitudinal model as in the cross-sectional model. However, after controlling for baseline suicide risk, baseline psychache and perceived burdensomeness were not significant predictors of suicide risk one month later, suggesting that previous suicide risk is the best predictor of future suicide risk. The alarmingly high number of individuals clinically at-risk for suicide in this study may indicate a general trend in IBD populations worldwide. These novel results may be of high clinical and research interest as they suggest variables for possible interventions targeting distal predictors of suicidal behaviour in order to mitigate their downstream effects.

abstract: M.Sc.


title: The role of von Willebrand factor in the pathogenesis of immunothrombosis

contributor:
Lillicrap, David
Pathology and Molecular Medicine

subject:
von Willebrand factor
inflammation
thrombosis
immunothrombosis

abstract:
Pathologic immunothrombosis is the formation of arterial, venous or microvascular thrombi in response to dysregulated activation of the immune system. Inflammatory diseases such as sepsis and obesity are associated with a hypercoagulable state that significantly increases the risk of thrombosis. Von Willebrand factor (VWF) is a hemostatic glycoprotein that mediates platelet aggregation at the site of vessel injury and carriers the coagulation cofactor, factor VIII, in circulation. The plasma concentration and procoagulant function of VWF are influenced by inflammation and elevated VWF levels are an established risk factor for thrombosis. The mechanisms by which inflammation interacts with VWF and other procoagulant effectors to promote thrombosis are incompletely understood.

In this thesis I describe VWF as both an effector of inflammation and a potentiator of immunothrombotic disease. We first showed that extracellular histones are potent inducers of endothelial cell VWF and mediate subsequent platelet capture in vitro. We also characterized the relationship between VWF levels and inflammatory mediators in murine and human models of acute and chronic inflammatory disease. We next used a mouse model of deep-vein thrombosis to assess the underlying prothrombotic phenotype associated with stabilin-2 deficiency, a scavenger receptor that was recently associated with increased risk of unprovoked venous thromboembolism. Deficiency of stabilin-2 produced a hypercoagulable state that was independent of VWF levels and was significantly associated with increased venous thrombogenicity. Finally, we used a mouse model of diet-induced obesity to study the role of VWF in a complex, thrombo-inflammatory disease. We demonstrated that VWF is critical for obesity-mediated immunothrombosis and is integral to both thrombus initiation and propagation.

These findings add to the growing rationale for targeting VWF-specific interactions in the context of immunothrombotic disease.

abstract: PhD


title: Du Pont's Wonder World of Chemistry: Corporate Culture as Public Culture in the Twentieth Century

contributor:
Brison, Jeffrey
Allan, Blaine
Cultural Studies

subject:
Public Culture
American History
Public Relations
Corporate Culture
Twenthieth Century
Du Pont

abstract:
During the twentieth century, business executives perceived a troubling trend amongst their employees and the general public: Americans appeared ignorant to the workings of the business system and were therefore susceptible to un-American political and economic philosophies. The major events of the century, including the Great Depression, World War II, and the Cold War, further fuelled the business community’s fears that a sweeping tide of government regulation, high taxation, and creeping socialism was threatening its traditional interests. In response, corporations launched public relations campaigns intended to correct what executives understood as misconceptions about the American economic system, and in turn, developed a public culture that championed free enterprise, production and consumption.
The chemical research company, Du Pont, also turned to public relations in the 1930s. Executives were spurred into action by negative press garnered by the Nye Commission, which branded the firm “merchants of death.” In 1935, the company launched its “Better Living” campaign, which lasted well into the 1960s. “Du Pont’s Wonder World of Chemistry: Corporate Culture as Public Culture in the Twentieth Century” details the ways in which Du Pont used public relations and its corporate sponsored-media as an opportunity to legitimize the firm’s existence and its corporate culture within the existing American socio-economic landscape. By examining the firm’s public relations materials intended to provide its employees and the general public with a better understanding of the American economic system, this dissertation explores how corporate public relations reverberated into a shared American public culture.
Throughout the twentieth century, Du Pont’s radio and television programs, films, company magazines, fair exhibits, press releases, and internal memorandums consistently and pragmatically asserted the necessity of big business within the American socio-economic landscape by conflating American history, and economic terms such as competition and production, with business-sponsored definitions of American liberties. Ultimately, Du Pont’s public relations is a window into corporate value creation, exploring the ways businessmen’s private interests translated into a public culture that valued free enterprise, consumption, and production as the only American way during the twentieth century.

abstract: PhD


title: Exploring the Washback Effects of the Chinese National Matriculation English Test (NMET) on Student Learning and Their Test Anxiety

subject:
Washback
NMET Washback Test Anxiety

abstract:
Washback refers to the effects of language testing on teaching and learning (Alderson & Wall, 1993). Washback studies have been frequently conducted in educational fields in the past several decades (Alderson & Wall, 1993; Cheng, 1997; 2005; Green, 2006; 2007; Qi, 2007). And those studies focus more on teaching and less on learning, so do the washback studies in the Chinese context (Gu, 2007; Gu & Peng, 2010; Qiao, 2006; Qin, 2012). The National Matriculation English Test (NMET) is the most populated large-scale high-stakes test in China with approximately 10 million test takers involved annually for admission to higher education. Thus, it offers a meaningful context to conduct research on washback as tests that have important consequences will have more intensive washback. Also, such important consequences as not being admitted to universities could lead to a potential source of heightened test anxiety, which was less researched. This study investigated the effects of the NMET in Hangzhou, Zhejiang province [hereafter referred to NMET (ZJ)], China on secondary school students’ learning and their test anxiety.
A quantitative data analysis (descriptive statistics, factor analysis and regression analysis) was conducted on 406 NMET (ZJ) test takers in Hangzhou in 2017. Results from the study are as follows: (1) Negative washback effects were observed on what and how students learned about English. (2) There existed a negative effect on students’ test anxiety. (3) Both a social context aspect of test anxiety (peer-related test anxiety) and a cognitive aspect of test anxiety (worry) were observed. Additionally, one of the two test anxiety factors (test unconfident) negatively predicted students’ English level. As students’ English level decreased, their confidence on the test also decreased.
The results indicate that the NMET reform in Zhejiang did not achieve its intended purpose of decreasing students’ test anxiety and promote their English learning. Both teachers and students should be aware of the negative effects of the test. Learning focus should be on genuine English learning instead of just learning for the test. Additionally, results on how changes of the test format negatively affect students also provide empirical evidence to test designers for future test development.

abstract: M.Ed.


title: Exploring Photochemical and Redox Reactivity of Four-Coordinated Organoboron Compounds

contributor:
Wang, Suning
Chemistry

subject: Photochemistry Organoboron Electrochemistry

abstract:
The works described herein are broadly concerned with exploring the characteristic reactivities and properties of four-coordinated organoboron systems, to fully understand and cultivate their utility and applicability. In particular, two different classes of chelate boron compounds are studied, namely N,C- and N,O-, with emphasis on investigating their response to external stimuli and unveiling the unique photophysical/optical properties inherent to these systems.
The first section of work described in this thesis focuses on the synthesis and study of new unsymmetrical N,C-chelate organoboron systems bearing two different aryl groups at the boron centre. These phenylpyrazolyl-chelated compounds have been found to undergo a rare, two-stage regioselective photoisomerization. The initial transformation is a di-π-borate rearrangement that affords yellow azaboratabisnorcaradiene isomers which are subsequently converted to unprecedented 14aH- diazaborepins. Spectroscopic and computational studies provide insight into the formation and properties of these unique systems.
A new series of N,O-chelate methylaminoanthraquinone-bridged diboron complexes have also been synthesized and their redox behaviour studied via cyclic voltammetry, EPR, and UV/Vis-NIR spectroelectrochemistry. It was found that coordination of boron to a commercial dye offered a redox- stabilizing effect, as well as tuning of the compounds’ colors and electron-accepting/-donating ability based on the substituents attached to boron. BF2 chelation induces a unique and rare golden lustre property, which was not inherent to the ligand itself and shows potential for future application.

abstract: M.Sc.


title: Understanding links between access to water, sanitation, and hygiene (WASH), and gender empowerment: Evidence from Ghana

contributor:
Bisung, Elijah
Kinesiology and Health Studies

subject:
Water Security
Gender
Empowerment
Equality
qualitative approach

abstract: Empowering women and girls is an important development goal as well as a way to improving access to water, sanitation, and hygiene (WASH) outcomes. However, empowerment is a complex and multi-dimensional concept, and it is often not clear how it is understood and presented in WASH sector programing. To address this gap, this dissertation broadly explores the meaning and dimensions of the concept of empowerment within the WASH sector. The data on which this dissertation is based were drawn from two sources: scoping review of existing studies and in-depth qualitative interviews conducted with 15 local stakeholders in the Asutifi North District, Ghana (chapter 4). Five major interrelated empowerment dimensions were identified in the review: 1.) access to information, 2.) participation, 3.) capacity building, 4.) leadership and accountability, and 5.) decision-making. Results from the interviews show that participants conceptualized empowerment in terms of four themes: availability of resources; WASH Information; social and cultural factors; and agency. The findings revealed that dimensions of empowerment are related and continuously interact as empowerment in one dimension could lead to (dis)empowerment in another. In addition, cultural and social contexts both shape and are influenced by the concept of empowerment. Findings from this research would provide researchers and practitioners with a greater understanding of dimensions of empowerment that are relevant for strengthening WASH interventions, as well as for tracking progress towards gender inclusion outcomes. This is particularly important to ensure inclusive WASH service delivery in low and middle-income countries (LMICs).

abstract: M.Sc.


title: The Toxic Effects of Oil Sands Contaminants on Developing Amphibians

contributor:
Orihel, Diane
Environmental Studies

subject:
Toxicology
Ecotoxicology
Amphibian
Oil Sands
Bitumen
Limnocorral
Wood Frog
Tadpole

abstract:
The Canadian oil sands contain a viscous form of crude oil known as bitumen. This research aimed to understand how contaminants from the oil sands industry can impact the growth and development of juvenile native amphibians.  The extraction of bitumen contributes to the atmospheric deposition of metals and polycyclic aromatic compounds (PACs) to snowpack which may be released to aquatic ecosystems upon snowmelt. Furthermore, due to increases in Canadian bitumen production and demand, transport via pipeline has amplified across North America, increasing the probability of bitumen spills in freshwater ecosystems. Using a common native species, the wood frog (Lithobates sylvatica), the
 developmental effects of contaminated snowmelt (Chapter 2) and a simulated diluted bitumen spill (Chapter 3) were tested in two semi-natural mesocosm-based experiments. Wood frog embryos were exposed to six snowmelt samples collected from the Athabasca oil sands at different distances from industrial operations for a period of 25 days. In addition, free-swimming wood frog tadpoles were exposed to lake water contaminated with seven environmentally relevant concentrations of diluted bitumen for a period of 21 days. Wood frog embryos exposed to contaminated snowmelt sampled from within a 50 km radius of mining operations accumulated PACs, displayed the altered expression of metamorphosis associated genes, experienced reduced development, impaired growth, an increased frequency of malformations, altered behaviour and delayed effects on growth and development after the end of the exposure. Wood frog tadpoles exposed to lake water contaminated with diluted bitumen had no measured change in thyroid hormone tissue concentrations (T3 and T4) and cytochrome P450 activity or expression. In addition, diluted bitumen contaminated lake water had no effect on the growth, development, or survival of tadpoles during the exposure period. Overall, contaminated snowmelt may impair the normal growth and development of wood frogs inhabiting wetlands near oil sands mining operations. However, the dissolved fraction of contaminants following a diluted bitumen spill may not impact the normal growth and development of wood frogs, provided the spill is rapidly and effectively remediated.

abstract: M.E.S.


title: Predicting Carbon Accumulation in Temperate Forests of Ontario Using a LiDAR-Initialized Growth-and-Yield Model

subject:
carbon accumulation
LiDAR
carbon stock
growth-and-yield model
mixedwood
temperate
FVSOntario

abstract:
Climate warming has led to a need for improved estimates of aboveground carbon accumulation (CA); in Ontario, this is particularly true for uneven-aged, mixedwood temperate forests, where there remains high uncertainty. This study investigated the feasibility of using LiDAR-derived tree lists to initialize a Growth and Yield (G&Y) model at the Petawawa Research Forest (PRF) in eastern Ontario, Canada. We aimed to see if models based on LiDAR-derived estimates of tree attributes provide comparable predictions of aboveground CA in complex temperate forests to those from inventory measurements.
Applying a local G&Y model (i.e., FVSOntario), we predicted aboveground carbon stock (CS; tons/ha) and CA (tons/ha/yr) using recurring plot measurements from 2012-2016, FVS1. We then used a suite of statistical predictors derived from LiDAR to predict stem density (SD), stem diameter distribution (SDD), and basal area distribution (BA_dist) using an algorithm. These data, along with measured species abundance, were used to construct tree lists and initialize a second G&Y model (i.e., FVS2). Another G&Y model was tested using LiDAR-initialized tree lists and Forest Resource Inventory (FRI) estimates of species abundance (i.e., FVS3). Models were validated using inventory data at years zero (2012) and four (2016).
The inventory-based model predicted equivalent CS at year four compared to validation data at all size-class levels, while LiDAR-based models did not; however, models were statistically dissimilar to validation data for CA. There was no significant difference between LiDAR-based models using inventory and FRI species through a 9-year period at the plot level (p<0.05), although forest type groupings were not always equivalent. We found equivalency of inventory and photo-interpreted models for size classes ≥17 cm.
Our results demonstrate the importance of precise tree size information when initializing G&Y models using LiDAR-derived estimates, the possibility of circumventing precise species abundance information when using G&Y models for CA, and that more work is needed on the use of LiDAR to quantify individual tree measurements in G&Y models for accurate predictions of CA. These results provide insight into techniques that can be applied regionally to quantify and forecast CA changes in Ontario, and for more informed carbon mitigation strategies.

abstract: M.Sc.


title: Turbulence and Sediment Resuspension Modelling in Lake Erie

contributor:
Boegman, Leon
Zhao, Yingming
Civil Engineering

subject:
Turbulence
Sediment resuspension
Lake Erie

abstract: Physical and biogeochemical observation in Lake Erie, and a field-scale numerical model was applied to study the turbulent dissipation and mixing, sediment resuspension and bottom stress parameterizations.  In Chapter 2, temperature microstructure data were processed and grouped to represent characteristic turbulent kinematic energy (TKE) dissipation rate (ε) and turbulent diffusivity (K_z) profiles in distinct regions of Lake Erie. The presence of a seasonal thermocline can increase ε up to 10^(-6)  (m^2  s^(-3)) and decrease K_z to molecular diffusivity in the bottom layer of the western basin and metalimnion of the central and eastern basins. The TKE budget shows efficiency of turbulent energy transfer from the wind decreased with increasing wind stress, and 36 - 54% of energy transferred from wind dissipated beneath the surface mixed layer, which was larger than that observed in smaller lakes.  In Chapter 3, a three-dimensional Reynolds-averaged Navier Stokes (RANS) equation model, coupled with a water quality model, was applied to simulate sediment resuspension in Lake Erie. The model was qualitatively validated and able to reproduce the timing of resuspension. The model showed surface wave-induced bottom shear stress dominated sediment resuspension in shallow western basin, and with contributions from up- and down-welling events, and internal Poincaré wave motions, the importance of mean current-induced bottom shear stress increased in central basin. Resuspension in the deeper regions (>25 m) of the central and eastern basins was not modelled.  To improve the prediction of sediment resuspension in field and model, bottom shear stress parameterizations, including surface wave stress method (τ_w), quadratic stress method (τ_c), log-law method (τ_L) and turbulent kinetic energy method (τ_TKE), were assessed in Chapter 4. In 2008-09 observations, resuspension induced by surface waves, bottom mean currents, and combination of them could be predicted by total bottom shear stress (τ_b), represented by τ_w+τ_c, τ_L, and τ_TKE. Considering required model setups (computing power, grid, etc.), τ_b= τ_w+τ_c is still the most practical parameterization method within field-scale RANS models. In comparison to observed values based on the same parameterization, the optimal algorithms of τ_w and τ_c in the RANS models showed 0.031 Pa and 0.025 Pa root-mean-square-error (RMSE), respectively.

abstract: PhD


title: N-Heterocyclic carbenes as novel ligands for metal surfaces, nanoparticles and nanoclusters

contributor:
Crudden, Cathleen
Chemistry

subject:
N-Heterocyclic carbenes
surfaces
nanoparticles
nanoclusters
materials chemistry
metal
stable materials
self-assembled monolayers
clusters
gold
copper
magensium
platinum
sensors
fluorescence
surface chemistry
self-assembly
catalysis

abstract: N-heterocyclic carbenes (NHCs) are carbon-based organic molecules that have been extensively employed as ligands for transition metal complexes for the past twenty years. They form stable metal complexes that can be used under conditions where other complexes would decompose. Despite their widespread use in transition metal chemistry, until recently, the employment of NHCs on metal surfaces has remained largely unexplored. This thesis describes the use of NHCs as novel ligands to functionalize planar metallic surfaces, curved gold nanoparticles and nanoclusters. We developed novel methods for the synthesis of air-stable benzimidazolium bicarbonates as single-source NHC precursors that were used to form high-quality films on gold surfaces. This enabled the facile preparation of identical monolayers to those formed using free NHCs but in the air, using undried solvents, with a single component precursor. Subsequently, we employed this simple generation of NHC monolayers to prepare various gold biosensors and functionalize other metals such as copper, platinum, and magnesium enabling unprecedented insight into structure-property relationships. In addition, we described the synthesis of amphiphilic NHC-functionalized gold nanoparticles where their self-assembly in polar solvents allowed the tuning of the collective optical properties and boosted the overall stability. Furthermore, we reported the first examples of gold superatoms, known as nanoclusters, protected by NHCs either by a displacement reaction or by the direct reduction NHC-gold complexes. The resulting NHC-phosphine-protected Au11 clusters were significantly stable and electrocatalytically activate toward the reduction of CO2 whereas the all NHC-stabilized Au13 clusters had exceptionally high photoluminescence greater than the most luminescent ligand-protected gold nanoclusters. We also obtained the first crystal structures of this new class of materials and showed the effect of the NHCs design on the cluster properties. The reported NHC-stabilized metallic materials in this thesis have unique properties that can open the door for further potential applications in biosensing, bio-imaging, microelectronics and catalysis.

abstract: PhD


title: Dialectical thinking and meaning-making in negative experiences

contributor:
Ji, Li-Jun
Psychology

subject:
dialectical thinking
meaning making
coping

abstract: Three studies were conducted to examine how dialectical thinking may contribute to meaning-making in negative experiences (MINE) tendencies and subsequently to people’s coping styles as they confront stressful situations. We examined dialectical thinking in two ways: (1) by comparing two cultural groups—Chinese and Euro-Canadians—that are well known to differ in dialectical thinking styles, and (2) by manipulating dialectical thinking in a single culture. Using a nine-item MINE scale with established measurement invariance across both cultures, we found that dialectical Chinese were more likely than non-dialectical Euro-Canadians to engage in meaning-making in negative experiences and to adopt acceptance and positive reframing coping styles (Study 1 and 2). Study 3 further demonstrated the causal effect of dialectical thinking on individuals’ tendency to engage in meaning-making in negative experiences by manipulating Euro-Canadians’ dialectical thinking. Compared to participants in the control condition, participants primed with dialectical thinking reported a higher tendency to engage in meaning-making in negative experiences and to adopt acceptance and positive reframing coping styles. The current research highlights the importance of the role of dialectical thinking in individuals’ tendency to engage in meaning-making in negative experiences and coping.

abstract: PhD


title: Angular Resolution and Directionality in SNO+

contributor: Physics, Engineering Physics and Astronomy

subject:
neutrino
scintillator
particle physics
astroparticle physics
SNO+

abstract: Solar neutrinos are an irreducible background for the SNO+ double beta decay experiment. Neutrino interactions in the SNO+ detector produce directional Cherenkov light which, if separated from the dominant scintillation light, would allow for neutrino direction reconstruction and elimination of solar neutrino signals. Other liquid scintillator detectors can benefit from direction information and understanding the factors that enable Cherenkov discrimination would be valuable. A Monte Carlo simulation was developed to determine whether this scintillation/Cherenkov discrimination is in fact possible. The effects of various factors including photomultiplier tube concentration and size, as well as different timing properties on the ability to perform photon discrimination were examined. Should it prove possible to distin- guish between the signals this will allow for a major improvement in the sensitivity of the SNO+ experiment and possible applications in other liquid-scintillator based detectors.

abstract: M.Sc.


title: Using social identity mapping to understand the implications of student-athlete group compatibility

contributor:
Martin, Luc
Kinesiology and Health Studies

subject:
social identity
student-athletes
sport
group compatibility
varsity sport

abstract: Social Identity refers to the extent to which people define themselves based on the groups to which they belong (Tajfel, 1981). Despite an extensive body of literature spanning several fields of psychology, most research on social identity has involved membership with only one group. Considering that humans are a social species, often belonging to several groups concurrently, investigating implications for multiple memberships is warranted. The purpose of this study was to explore social identity compatibility in interuniversity athletes, with a specific interest in assessing associations with quality of life and academic and athletic performance. A total of 235 interuniversity athletes (57% female; Mage = 19.98 years; SD = 1.77) completed an online social identity mapping tool (oSIM; Cruwys et al., 2016), and questionnaires assessing the criterion variables. Results indicated that two mediation models were statistically significant. First, general health quality mediated the relationships between the proportion of very incompatible groups and individual perceived athletic performance. Second, a specific dimension within health quality, emotional health quality, also mediated the relationships between the proportion of very incompatible groups and perceived athletic performance. These results are discussed in terms of both their theoretical and practical implications within the thesis. However, as a generally summary, our findings suggest the importance of experiencing harmony among group memberships, and that this is particularly important in populations with overt group affiliations. Within the thesis, limitations are also acknowledged (i.e., cross-sectional research design) and suggestions are made to promote future research using the novel online oSIM tool in sport.

abstract: M.Sc.


title: Optimization of a Generated Intrusion Detection System

contributor:
Dean, Thomas
Electrical and Computer Engineering

subject:
Optimization
Intrusion Detection
Parallelism
Multi-Threading
Parsing
IDS Generator
Grammar Analysis
Synchronization
Lookahead
TXL
Network Protocols

abstract:
As technology continues to evolve at a rapid pace, the opportunities for malicious attacks and vulnerabilities grows equally. Constant monitoring of networks is required to prevent attacks, even in networks without any external connections. We often use software known as Intrusion Detection Systems (IDS) to parse, analyze, and constrain data in a network to follow normal traffic patterns. Combined with specifications detailing the form of that traffic and real-time learning, they are effective at detecting attacks.

Achieving near-perfect results in intrusion detection is not an easy task. Many of the current top IDS technologies have the analysis infrastructure required of such a task but fall short of the goal. Inefficient algorithms, communication, and architectures cause these systems to process data at a rate slower than their input.

Improvements to the parsing and analysis components of any IDS is the key to improving their detection-rate. Current systems attempt to incorporate efficiency into their design such as dedicated parse routines or detect profiles to avoid duplicate traffic. However they are often not general, offering improvement only in certain scenarios, or not impactful enough.

In this thesis, we propose several dynamic optimizations for Intrusion Detection Systems as a whole, implementing them in a state-of-the-art test system. We develop parser side optimizations capable of analyzing protocol specifications to decode them more efficiently. A deep grammar analysis investigates conglomerate data structures that should be separated and treated as individual entries. A lookahead process then follows to prevent inefficient backtracking parse algorithms.

We additionally investigate the concept of parallelism through a decoupling of the parser and analysis components of the IDS. Using multi-threading synchronization, we are able to dispatch multiple instances of each process. This allows additional data to flow through the system to further reduce the chance of data overflow. Our parallel architecture itself includes multiple optimal algorithms and efficiencies, including memory pools, lock reduction, and intelligent threading. The entire parallel system, including optimizations is dynamically generated from an input set of network protocol descriptions. Therefore allowing parallelism access to any developer who implements the IDS, avoiding the traditional large development cost of parallel programming.

abstract: M.A.Sc.


title: The Role of Cooling Rate on Microstructure in Sand-Cast Aluminum A205

contributor:
Diak, Bradley
Gallerneault, Mark
Mechanical and Materials Engineering

subject:
Aluminum
Al-Cu alloy
Grain refiner
Sand casting
Solidification
A205
Microstructure
Cooling rate

abstract:
Modern aerospace castings consist of highly complex geometries that require solidification simulations to optimize fill pathways so to control the thermal evolution and thus microstructure during solidification. Accurate solidification simulations require knowledge of the melt physical properties, mold-filling sequence, mold material properties and subsequent validation by thermal and microstructural measurements. The present work describes the most significant challenges and detailed methodology to maximize a multi-thermocouple acquisition system used to measure transient temperatures during solidification of aluminum alloy A205, and to correlate the measured transients to microstructural observations for three complex full-scale castings and a control refractory cone geometry. The control geometry was used to directly correlate a continuous gradient in cooling rate to variations in the microstructural grain size. The resulting microstructures and their morphologies in the local regions surrounding the thermocouple tips were linked via an empirical relation to the calculated cooling rates. The empirical relation incorporates the TiB2 grain refiner level and an approximation of the A205 alloy-specific growth restriction factor, Q. Results indicated that there was a high correlation (R^2=0.99) to an inverse square root relationship in the measured grain sizes (d) with respect to the calculated initial cooling rates (T ̇) during solidification of the primary α-Al phase for material from all sampled molds as
d(μm)≈A/[4.5]^(1⁄3) +B/(85∙T ̇^(1⁄2) )          (i)
with the fitting parameters A=55.0±9.2 μm∙[wt.%]^(1⁄3) and B=1371±121 μm∙K^(3⁄2)∙s^((-1)⁄2). This relationship is important because it allows for the average as-cast grain size to be predicted in A205 alloy for initial cooling rates commonly observed during sand casting. The microstructural knowledge of A205 alloy was also extended into the 3rd dimension through micro-computed tomography, indicating that the cast microstructure is isotropic and granular in nature, even in the presence of large thermal gradients.

abstract: M.A.Sc.


title: Phononic Crystal Surface Structures on Gallium Arsenide

subject:
phononic crystal
surface acoustic wave
gallium arsenide
waveguide
Rayleigh wave
Sezawa wave
elastic wave
Lamb wave

abstract:
A series of computational studies of surface phononic crystals on cubic gallium arsenide are explored to elucidate the behaviour of surface acoustic waves in such systems. The enhanced understanding of surface acoustic wave propagation in phononic crystals may contribute to practical application in quantum well devices. A wet-etched phononic crystal waveguide in gallium arsenide with approximately two micron deep inclusions is studied numerically and compared experimentally for controlled surface acoustic wave propagation. The computed filter response of the phononic crystal confirmed that the phononic crystal was an effective stop band filter in the interval of 400 MHz and 450 MHz. An L1 linear defect waveguide with a stepped funnel entrance design is shown to perform well at a surface acoustic wave frequency of 410.344 MHz and in agreement to simulated results.

Next, surface acoustic waves in two-dimensional phononic crystals consisting of shallow void inclusions are studied via its eigenmodes. For the [110] propagation direction on a (001) gallium arsenide half-space, the conventional Rayleigh wave modes, the layered substrate-associated Sezawa and Lamb modes, the high frequency longitudinal surface waves and bulk waves exhibit hybridization and modal interaction. The longitudinal and vertical shear bulk wave dispersions are observed to be significant thresholds for surface acoustic waves on a shallow phononic crystal exemplified by strong attenuation and mode anticrossings while the shear horizontal wave functions as a more weakly interacting sound line. However, surface modes with low attenuation and exceptional surface boundedness do exist above these sound cones similar to those in thin film coated substrates. These surface modes consist of either Rayleigh-Sezawa or Rayleigh-longitudinal hybridized modes. Phononic viscosity augmentation  of stiffness, finite substrate depth and off-angle with respect to [110] propagation are contrasted for surface acoustic wave propagation. Finally, finite-width, defect-free waveguides on gallium arsenide are explored in contrast to earlier linear defect waveguides. The phononic crystal itself provides the medium of the waveguide core, whereas the cladding is provided by the surrounding gallium arsenide substrate. A finite-width waveguide shows promise for further development in charge and spin transport on gallium arsenide.

abstract: PhD


title: Exploiting ultrafast optical pulses: probing excitonic properties of 2D materials and utilizing the Kerr effect for all-optical switching

subject:
Ultrafast
All-Optical Switch
2D Material
Excitons
Optical Kerr Effect
Transition Metal Dichalcogenide
Photoluminescence
Single Mode Fiber
Polarization Rotation

abstract:
Ultrafast optics technology involves the development and application of femtosecond optical pulses. The work presented in this thesis consists of two research objectives which exploit these aspects of ultrafast optics technology.

In Part I of this work, we implement a method for probing the excitonic response of 2D MoS2. Excitonic properties of samples are investigated through photoluminescence (PL) mapping, which we demonstrate as a valuable characterization method. PL mapping is used to determine the number of layers present in samples of 2D MoS2. Monolayer MoS2 exhibits a PL peak intensity ∼ 5 times that of bi-layer, with a blue-shift of 18 ± 3 meV. We demonstrate the influence of MoS2 sample growth and preparation mechanisms on its excitonic response. The Exciton A peak of mechanically-exfoliated MoS2 (at 1.8958 ± 0.0006 eV, with FWHM 46 ± 2 meV) is narrower and blue-shifted compared to that of a sample grown via chemical vapour deposition (at 1.845±0.005 eV, with FWHM 110±5 meV). We also observe evidence of an increase in total PL intensity for regions of localized rips and tears in exfoliated samples, and a decrease in trion activity for samples isolated via hBN-encapsulation. Finally, we present initial measurements of ultrafast exciton lifetimes in monolayer MoS2 (0.99 ± 0.18 ps and 14.78 ± 1.94 ps) via femtosecond excitation correlation (FEC) spectroscopy.

In Part II of this work, we demonstrate the “carving out” of polarization-switched ultrafast optical pulses (424 fs in duration) from a continuous beam of light, through the optical Kerr effect. In addition to establishing this as a reliable technique for measuring intrinsic switching speed, we demonstrate the configurability of our switch. Our switch is capable of generating ultrashort pulses (with tunability in spectral bandwidth of 1.6–2.9 nm) and switched 2- and 4-pulse trains (with 2.2 ps temporal separation). Our all-optical switch holds potential in a number of technologies, particularly in optical communication and as a new ultrafast light source.

abstract: M.Sc.


title: Monitoring Laser Material Processing by Simultaneous Inline Coherent Imaging and Integrating Sphere Radiometry

subject:
Laser Material Processing
Inline Coherent Imaging
Integrating Sphere Radiometry
Laser Welding

abstract: Understanding the underlying physics of laser welding and metal additive manufacturing (AM) is crucial to the advancement of laser-based manufacturing. One aspect that especially requires careful attention and control is the formation and evolution of vapour depressions, or keyholes, within the melt pool. The dynamic geometric behaviour of these depressions is intrinsically linked to the instantaneous energy coupled into the system, and therefore has a dramatic effect on the final properties of the material. In this work, we combine integrating sphere radiometry (ISR) and inline coherent imaging (ICI) to simultaneously measure time-resolved absorptance and vapour depression depth during stationary, high-irradiance laser illumination of a metal (AISI 316 stainless steel). This allows, for the first time, the exploration of the complex interdependence between energy coupling and geometry that underpins important industrial processes such as laser welding and additive manufacturing. Vapour depression depth measurements are acquired at a rate of 200 kHz and the time resolution of absorptance measurements is 4.4 µs. Time-resolved data reveals a general correlation between vapour depression depth and absorptance at high laser irradiance, showing that greater depth leads to an increase in absorptance from about 0.4 up to 0.9. There is also specific correlation with temporal features such as vapour depression initiation and oscillation frequency during periods of instability. An understanding of traditional welding regimes (conduction and keyhole mode) is enhanced by revealing distinguishing time-resolved features, and a transition mode is shown that exhibits behaviour of both regimes. Finally, the experimental results are compared with ray-tracing simulations that provide validation and explanation of the results, most notably revealing the first experimental observation of an incremental increase in number of laser beam reflections due to increasing vapour depression depth. The work presented here provides new insight into the underlying physics of laser-based manufacturing that can be used to advance progress towards deterministic control of the process.

abstract: M.A.Sc.


title: Correction of AB Variant GM2 Gangliosidoses Using AAV9 Viral Vector Gene Therapy in a Mouse Model

contributor:
Walia, Jagdeep
Neuroscience Studies

subject: AB-variant GM2 gangliosidoses

abstract: GM2 Gangliosidoses are a group of neurodegenerative diseases affecting the brain. In humans, these diseases are characterized by rapid neurological deterioration and death before 4-years of age. GM2 gangliosides are normally degraded in a cell’s lysosomes through the action of three gene products, HEXA, HEXB, and GM2A. A defect in any one of these genes can result in a deficiency of Hexosaminidase A (HexA) enzyme activity, which then cannot breakdown GM2 gangliosides. The rarest form of these diseases, the AB-variant (AB- GM2), is characterized by a mutation in the GM2A gene encoding the GM2-activator protein (GM2AP), which is a required co-factor for the HexA protein. The aim of this study is to give a one-time treatment of single stranded (ss) AAV9/GM2A viral vector therapy at a dose of 1 x 1014 vector genomes per kilogram of mouse and to see at least biochemical reduction in GM2 ganglioside storage in both the short- and long-term treated cohorts. ssAAV9/GM2A plasmid was created and tested in vitro on a GM2AP-deficient patient cell line to confirm the expression of the protein using Western Blot analysis. Later, treatments were given to 1-day old pups via the superficial temporal vein, as well as 6-week old adult mice via tail vein, to correct AB- GM2. These mice underwent monthly behavioural testing, as well as biochemical and molecular analysis performed at 20- and 60-week end-points. We hypothesized that an optimized ssAAV9/GM2A treatment can correct the gene mutation as well as phenotype of AB- GM2 in mice. Biochemical data for both end-points showed reduction in GM2 gangliosides storage in the treated cohorts compared to the vehicle cohorts for both the neonatal and adult treated cohorts. Behavioural data for the 20- and 60-week end-points, as well as the neonatal treated and adult treated mice, showed the treated cohorts inconsistently outperformed the vehicle cohorts. Almost uniform biodistribution of the hGM2AP vector was also seen across the rostral section, caudal section, mid-section and liver. This proof of concept study is a step forward towards the development of a therapeutic approach for AB-GM2 and towards our goal of human clinical gene therapy trials.

abstract: M.Sc.


title: Assessing the Effectiveness of a Transformational Coaching Workshop on Athlete Outcomes

contributor:
Cote, Jean
Kinesiology and Health Studies

subject: TFL PYD CDP

abstract: Positive youth development (PYD) through sport is a person-centered approach that aims to develop a variety of assets. Coaches can play a significant role in this process but often require training to develop their professional, interpersonal, and intrapersonal skills and knowledge. Recently, a coaching development program (CDP) grounded in Transformational Leadership theory (TFL) has been shown to increase coaches’ interpersonal behaviors that focus on the development of the person. However, how this training affects athletes’ outcomes has yet to be tested. The purpose of this thesis, therefore, is to test the effects of a Transformational coaching workshop for developing athletes’ competence, confidence, connection, and character—also known as the 4Cs. Fifty-three soccer athletes (Mage = 13.7, SD = 1.91 ) completed four questionnaires before and after their coaches participated in the workshop. Seventy-two soccer athletes (Mage = 14.24, SD = 1.27 ) served as a comparison group and had coaches that did not participate in the workshop. Four separate tests were run to analyze differences in the 4Cs at two time points during the season across the two groups. Two repeated measures ANOVAs were run for competence and confidence, while two repeated measure ANCOVAs were run for connection and character while controlling for age and gender respectively. The results show that the intervention had no significant effects on athletes 4Cs. Athletes in both groups appeared to be situated in a nurturing environment before the workshop and continued to benefit from this environment after the workshop. The findings add to the growing body of research that shows CDPs may not benefit those who are already developing optimally and who perceive their environment positively. However, the high averages for both groups at both time points indicate that the ceiling effect and social desirability bias might be influencing the findings. These constraints on the results appear to be a growing trend in CDP and PYD research and thus open a discussion to suggest the need for more sensitive instruments and rigorous methodologies in future studies.

abstract: M.Sc.


title: Disability, Career Advancement, and Leadership

contributor:
Spitzmuller, Matthias
Business

subject:
Disability
Career advancement
Leadership
Management
Quantitative methods
Qualitative Methods
Leaders with disabilities

abstract: My dissertation includes three research papers on disability, career advancement, and leadership. With limited prior research on the lived experience of leaders with disabilities, I begin with a qualitative study on career advancement and leadership facilitators in Chapter 2. Twenty-one leaders with disabilities participated in this study. Participants explained how they benefited from three types of facilitators during their career advancement, including career self-management strategies, organizational and societal factors, and social networks. These facilitators are synthesized with a metaphor called the three-legged stool. This metaphor portrays the importance of three foundational pillars that underlie career advancement and leadership among persons with disabilities. Directing attention to an understudied element of one of those pillars—social networks—I report how leaders’ external networks (e.g., family, friends, acquaintances, and role models) facilitated their career advancement and leadership as well. Having explored facilitators of career advancement and leadership in Chapter 2, I move on to study the relationship between disability and career advancement with a quantitative, archival study in Chapter 3. The literature provides varied reports on this relationship, and importantly, this stream of research has tended to focus on disability as a homogenous construct. However, in reality, disability is multifaceted and complex. Therefore, I examine whether disaggregating disability by type (physical, sensory, mental, and multiple disabilities) might better predict promotion rates. This analysis includes data from 4025 National Longitudinal Survey of Youth 1997 respondents. Although initially promising, data limitations result in a discussion focused on future research. My final empirical chapter, Chapter 4, includes experiments on how observers perceive leaders with and without a disability. These studies focus on when bias is expected to arise. Overall, 578 Amazon Mechanical Turk users participated in the studies of this chapter. Results illustrate how the stereotype-fit (good-fit/poor-fit) of a focal leader’s role and disability influence hiring expectations of that leader. However, only after the leader has made a mistake. Findings on leaders without a disability were not consistent with those on leaders with a disability. This dissertation has implications for research, practice, and persons with disabilities that I discuss in the following chapters.

abstract: PhD


title: Photochemical Reactivity and CO2 Sensing Applications of Organoboron Compounds

subject:
Photochemical Reactivity
Photophysical Property
CO2 Sensing
Organoboron

abstract:
The works described herein are focused on the investigation of photo, thermal and CO2 responsive properties of boron-containing π-conjugated systems in order to develop an in-depth understanding of the relationship between molecular structure and photophysical properties and to further expand the application fields.
Rapid progress in the field of N,C- and C,C-chelate organoboron photochromic materials over the past ten years has been focused on the impact of different π-conjugated backbones and the effects of different substituents on the chiral boron center. Despite the well-developed nature of this field, limitations still exist such as the need to have at least one bulky mesityl group present on the boron atom. To remedy this deficiency, we investigated a series of N-alkyl substituted benzylideneamines with boryl groups attached at the 2-position with the goals of simplifying the starting material structures of photoactive organoborates. Furthermore, we hoped to increase their reactivity in order to generalize their photoreactions for the preparation of a variety of B=N containing 7- and 8-membered ring systems with four different substituents on the B=N unit. Chiral N,C-chelate organoboron compounds bearing two different aryl groups (phenyl, tolyl,  naphthyl) at the boron center have been found to undergo regioselectivie photoisomerization, generating various 7-membered ring systems via H-atom transfer. Furthermore, functionalized with non-bulky heterocycle substituent (thienyl) of this kind of N,C-chelate organoboron compounds enables quantitative phototransformations yielding chiral N,B,S-embedded heterocycles.
The impact of intramolecular H bonding and n-π* interactions on photophysical properties of laterally appended D-π-A triarylboron compounds with biphenyl units were studied systematically. Some of these compounds have been found to display fluorescent response toward CO2. To further improve the CO2 sensing properties, three new alkylamino-appended D-π-A triarylboron have been found with the ability to capture CO2 with the formation of carbamic acid and detect CO2 with, obvious fluorescent color change, high sensitivity and good reversibility. In addition, this system is also effective as fluorescence “turn-on” temperature probes due to the dynamic B ← N bond dissociation/association.

abstract: PhD


title: Portable Microfluidic Platform Employing Young-Laplace Pumping For Multiplexed Lab-On-A-Chip Applications

contributor:
Oleschuk, Richard
Chemistry

subject: Microfluidics Analytical Pumping Flow

abstract:
Fast, cost-effective, portable and simple to use devices are highly relevant in the current field of medicine. “Lab-on-a-chip” devices are of special interest, as they enable the user to quickly perform tests with small concentrations of sample/analyte. The invention of affordable solutions to accurately perform sample preparation and analysis without the need for expensive equipment and trained personnel is of significant importance to our society. Specifically, the accurate distribution of microliter-sized volumes onto microfluidic systems is a process that needs to be streamlined to make the use of “lab-on-a-chip” devices as straightforward as possible.
This work focuses on the development of a platform that utilizes surface tension induced pumping based on Young-Laplace pressure, which allows modifiable transport of fluids without external modules, making it an attractive approach for microfluidic applications. Using 3D-printing, a platform was developed that enables the distribution of specific liquid volumes onto a superhydrophobic chip that is modified with (super)hydrophilic areas called surface energy traps (SETs). The SETs are fabricated by a facile picosecond laser micromachining ablation method out of commercial NeverWetTM coated glass slides. The 3D printed platform allows for simultaneous initiation of Young-Laplace induced pumping on a chip. Furthermore, the flowrate of Young-Laplace induced pumping is adjustable through different designs and SET parameters (including length, width, and radius), allowing detailed flow control over liquid transport. Droplets within the range of 10-140 μL (7.3% deviation) can be distributed using adjustable and interchangeable component designs. Moreover, it is shown that the advantages and flexibility of this platform can be employed to enable and simplify the process of simultaneous on-chip experiments for silver nanoparticle and nanocluster synthesis. This work builds a promising groundwork for future lab-on-a-chip devices. An approach is discussed that can be employed to design and develop on-chip bio-immunoassays (e.g. employing sandwich-ELISA) for pathogen detection utilizing the platform developed in this work, thus creating a portable affordable and simple to use point of care lab-on-a-chip device that possesses significant value and interest to the field of medicine and to society overall.

abstract: M.Sc.


title: Performance analysis of attack-resistant trust computation schemes in multi-hop vehicular ad-hoc networks

contributor:
Kim, il-Min
Electrical and Computer Engineering

subject: trust computation

abstract:
With the development of the autopilot technology, the autonomous vehicles mainly rely on the in-car cameras to monitor the surrounding environments. A wider view will make the autonomous vehicles safer while driving. In order to extend the view of the autonomous vehicles based on messages sharing with others, security issues should be considered.
The traffic condition warning application of the intelligent transportation systems (ITS) in the vehicular ad-hoc network (VANET) could alert the road conditions ahead and assist drivers to avoid the potential dangers on the highway. An event on the traffic will be detected and reported by the vehicles passed by. The rear vehicles derive the evidence from the reports and combine them through decision logic mechanisms. The decision logic classified as the data centric trust management scheme is applied for mitigating the misleading of the untrusted reports and assisting the vehicle drivers to make correct decisions. The reputation parameter may further improve the accuracy of the decision logic mechanism by evaluating the trust of a single report. However, due to the large-scale and ephemeral properties of the vehicular networks, a secure trust computation mechanism is required for the trust assessment of the reports forwarded over multiple hops.
We adopt the conventional trust computation mechanisms into the vehicular scenarios and simulate the attack-resistant performance. We mainly focus on the bad-mouthing attack and randomize the behaviors of the honest and malicious nodes based on this attack. The directed trust graph for the trust computation is generated based on the network topology of vehicles on highway. The simulations consist of the influences of the distinguishable ability of the honest nodes, the positions of the attackers in the directed trust graph, and the number of attackers in the network. Furthermore, we study the performance of the trust computation mechanisms and derive useful insights. Based on the insights, we further adjust the trust computation mechanisms and conclude their strengths and limitations. Moreover, we derive the applicable conditions for different trust computation mechanisms.

abstract: M.A.Sc.


title: Words without Deeds: A Toxic Culture of Leadership and Gender Integration in the Canadian Forces, 1989-1999

subject:
Military
History
Canadian Forces
Decade of Darkness
Women

abstract: In 1998, the Chief of Review Services (CRS) assessed the Canadian Forces (CF) had fell short in reaching “full integration,” a goal which the Canadian Human Rights Tribunal (CHRT) gave the Canadian military in 1989. The CRS noted, from interviews of servicewomen, that leaders would say “the right thing,” yet leaders seemed “unaware of problems” and appeared to “condon[e] negative behaviours.” Therefore, in the 1989-1999 phase of gender integration, leaders did not express a commitment to gender integration in word and conduct. In fact, in the CF culture of leadership during the 1990s, inaction, breach of discipline, ambivalent attitudes, and deceit were common practices. This thesis explores how a toxic leadership culture rife in the Canadian military during the 1990s (also known as the “decade of darkness”) contributed to the shortcomings of gender integration, in that it let the development of a climate antagonistic to women that infiltrated all ranks of the CF, and affected the behaviours of subordinates and peers, both male and female.

abstract: M.A.


title: Neutrophil NETosis, viability, and gene or protein expression in response to surface chemistry using isodecyl acrylate copolymer coatings

contributor:
Wells, Laura
Chemical Engineering

subject:
Neutrophils
Biomaterials
Polarization
Inflammation
NETosis
Gene Expression

abstract:
Undesirable host responses to implants commonly lead to impaired device function. Biomaterial-based strategies focused on neutrophil behavior to improve host responses to implants have not been significantly researched. As the first immune cell to respond to inflammation, neutrophil activation resulting in the release of antimicrobials and neutrophil extracellular traps primes this microenvironment for macrophages and other infiltrating cells. Methacrylic acid (MAA) and methyl methacrylate (MM) based polymers modulate healing responses through altered macrophage behavior and vascularization. This project investigates the neutrophil response to MAA and MM copolymerized with isodecyl acrylate (IDA) (MAAcoIDA and MMcoIDA) and hexamethylenediamine-functionalized MMcoIDA coatings (HMD-MMcoIDA).
In this research, MAAcoIDA and MMcoIDA were coated onto glass coverslips and MMcoIDA. MAAcoIDA coatings had 4975 ± 580 nmol/cm2 of carboxyl groups at the surfaces while MMcoIDA was further functionalized to add 58 ± 18 nmol/cm2 of amine groups to the surfaces via aminolysis with HMD. The HL60 cell line and murine bone marrow derived neutrophils (BMDN) were then incubated with the coatings to study neutrophil-material interactions. HL60 gene expression and viability were assessed to determine inflammatory and anti-inflammatory characteristics induced by the different surface chemistries. NETosis, indicated by citrullinated histone H3 (citH3), elicited by the coatings was visualized for both HL60 cells and murine BMDN, and protein synthesis was additionally quantified for BMDN.
HL60 cells demonstrated increased viability when incubated with MAAcoIDA relative to MMcoIDA. HL60 viability on HMD-MMcoIDA decreased after 48 hours, coinciding with increased citH3. HL60 cells exhibited increased expression of ICAM-1 and TNF-α when incubated on aminated coatings compared to those with MMcoIDA or MAAcoIDA after 48 hours.
Murine BMDN displayed lower ratios of viable cells on the coatings than uncoated glass, and cells with MAAcoIDA coatings underwent less histone citrullination while HMD-MMcoIDA elicited increased histone citrullination, relative to MMcoIDA. BMDN secreted varied concentrations of MIP-1α and MIP-2 in response to coatings with no added stimulus after 2 hours and increased over 16 hours, although no significant differences were noted between surface chemistries. Future work looks to characterize these coatings and examine protein-material interactions, as well as follow up studies with these materials in vivo.

abstract: M.A.Sc.


title: Application-specific parsing of text-based network protocols

subject:
Parsing
Text-based protocols
Intrusion Detection
ANTLR
Constraint-based intrusion detection
Application-specific

abstract: Application-specific parsing can be used to extract application data presented in a format that is customized to a particular application.  Effective parsing of application data found in network traffic sets a solid ground to develop application-level traffic analysis software. An example application of application-level traffic analysis software is an intrusion detection system that works at the application-level.  In this thesis, we  present  our  work  on  message  categorization  and  targeted parsing  of  text-based network  protocol  messages.   We  categorize  protocol  messages  into  types  and  parse each message with a parser targeted for that type of messages.  We created a parser specification  language  to  automatically generate  custom  parsers.   The  specification language is used to define the types of protocol messages, names of the grammars to be used for parsing, application data parts of a message and functions to be applied on  the  parsed  data.   We  use  the  parser  generation  framework  ANTLR  to  generate parsers for our system.  We tested our parser approach on network traffic generated by four different applications running over text-based protocols.  Our parser was able to parse any application data found in the network traffic.  We created a Constraint Engine to demonstrate how our parsing system can be used to validate application-level constraints on network traffic.

abstract: M.A.Sc.


title: Reconfiguring Empire Gently: Indians and Imperial Reform, 1917-1947

contributor:
Chowdhury, Amitava
Aiyar, Sana
History

subject:
Global History
British Empire
South Asian Diaspora
Settler Colonialism
World War One
Liberalism
Commonwealth
South Africa
India
Twentieth Century
Race
Migration
Citizenship
Nationalism
Imperial Reform
Indian Moderates
Indian Liberals
Decolonization
Diaspora
Indenture
Greater India
Gopal Krishna Gokhale
V. S. Srinivasa Sastri
Servants of India Society
Bhawani Dayal Sannyasi
P. Kodanda Rao
Benarsidas Chaturvedi

abstract: This dissertation gives an overview of imperial reform as one of many responses to late colonial rule which existed alongside and in conversation with anticolonialism. I argue that the argument for imperial reform in India sought to institutionalize Indian settler citizenship within white settler citizenship. I delve into the importance of the interwar period as one in which Indian “nationalism” stood for many different possibilities for engagement with the struggle against imperial hegemony, including both reform and anticolonial nationalism, among others. Indian liberals put forward the case for imperial reform during meetings of the British Commonwealth in the aftermath of the First World War. They tried to act as brokers between the Government of India, Indians overseas, white settlers, and Indian public opinion in order to facilitate programs for imperial reform which they negotiated for at meetings of the British Commonwealth. The history of imperial reform was entangled with that of Indian subimperialism. Imperial reform was an argument that fell in and out of favour within a global network of concern for Indians overseas. The Indian Reciprocity Act marked Indian liberals’ disillusionment with the possibility of empire as the framework upon which Indian inclusion within a global system of liberal states could rest. This dissertation challenges the teleologies of postcolonial nationalist histories which assume the inevitability of anticolonial nationalism and the postcolonial nation-state as the exclusive responses to imperialism. The history of Indian liberal politics during the interwar years only becomes possible when the container of contemporary South Asia’s borders are set aside as units of analysis. Understanding responses to imperialism and critiques of empire outside of anticolonialism is only possible when the artificial barrier separating the histories of the global Indian diaspora and the Indian subcontinent during the interwar years are collapsed.

abstract: PhD