title: The Relationships That Help Teenage Syrian Refugees Cope With Stress

title: Teenage Syrian Refugees: Stress, Support, and Coping

contributor:
Nouvet, Elysee
Global Health

subject: Refugee Culture Stress Coping Teenagers

abstract:
Millions of Syrians have been displaced due to the events of war since 2011.
Among those, half of them are youth under the age of 18. In 2015, Canada launched an initiative to be a new home for Syrian refugees, and youth accounted for a large amount of those resettled. Pre-migration and post-migration stressors have been noted to have profound impacts on mental health and well-being. Additionally, adolescence is a crucial period of psychosocial development, which for Syrian youth has been drastically changed as a consequence of war. This includes being uprooted from their communities of family, friends, and religious groups, as such social support systems are important resources in buffering against stress. The research surrounding adolescent Syrian refugees’ experiences of stress and coping is slowly growing. However, little is known about how teenage Syrian refugees in Canada utilize social support. Therefore, it is important to gain understanding of how teenage Syrian refugees use their social support systems to cope with stressors. Semi-structured interviews were conducted with adolescent Syrian refugees (n=9) aged 16-18 who live in Ontario. The interviews were transcribed and analyzed using Interpretative Phenomenological Analysis.
 The findings suggest that youth face pre migration stressors related to the war and post migration stressors related to acculturation and navigating the education system. Family, peers, school staff, and organizations were identified as forms of social support, with each group having unique reasons as to why they were selected. Coping behaviours were broadly categorized as being inherently individualistic or collectivistic. Teenage Syrian refugees draw upon or seek out resources to navigate complex situations they are faced with, and cultural values influence the stress and coping process. These findings may have implications for mental health providers who work with teenage Syrian refugees, the education system, and policy makers who focus on refugees.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: The goal of the present study was to understand how teenage Syrian refugees in Canada use their social support systems to cope with stressors. Semi-structured interviews were conducted with nine participants to explore three areas of interest: social supports, coping behaviours, and stressors. The findings suggested that teenage Syrian refugees are able to navigate new and complex situations by drawing upon, or curating, resources. Additionally, culture was a factor in shaping their experiences of the stress and coping process. The results of this study can help mental health providers and those who focus on refugee related policies.


title: Theologies of Israel and Judaism After Barth

contributor:
Widdicombe, Peter
Religious Studies

subject:
Karl Barth
Doctrine of Israel
Paul M. van Buren
John Howard Yoder
Robert Jenson
Christian Theology of Judaism
Christian Theology of Israel
Post-Holocaust Theology
Supersessionism
Post-Supersessionist Theology
Israellehre

abstract: This thesis examines three students of Karl Barth’s work, all of whom articulate Christian theologies of Israel and Judaism under the influence of his thought and thus the wording of the title, after him. The three theologians are Paul M. van Buren (1924-1998), John Howard Yoder (1927-1997), and Robert Jenson (1930-2017). All three studied with or were supervised by Barth during the 1950s. Later, each of them would make significant contributions to post-Holocaust theologies of Israel and Judaism. In this thesis, I seek to elucidate the conceptual relationship between these two elements—each theologian’s early engagement with Barth and their later contributions to post-Holocaust theology—and argue that by examining the former, one can better understand the theological bases for the latter. I begin with an analysis of Barth’s doctrine of Israel. Barth claims that Israel and rabbinic Judaism are eternally determined to be witnesses to God’s own self-determination in Jesus Christ to be the God whose mercy rules in God’s judgment. A close comparative reading of van Buren, Yoder, and Jenson then follows. I begin by outlining the ways these three theologians appropriate and depart from Barth during or shortly after their time studying with him. I then trace the way each theologian’s early appropriation of and departure from Barth relates fundamentally to the development of their theologies of Israel and Judaism. My analysis reveals that each of the three critique Barth’s doctrine of God’s self-determination as the pre-determination of the identity of Israel and Judaism to be witnesses of Jesus Christ. This common critique enables each of the three to articulate a more positive account of Israel’s and rabbinic Judaism’s witness.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: This thesis examines three students of Karl Barth’s work, all of whom articulate Christian theologies of Israel and Judaism under the influence of his thought and thus the wording of the title, after him. Paul M. van Buren, John Howard Yoder, and Robert Jenson studied with or were supervised by Barth in the 1950s. Each of them would later make significant contributions to post-Holocaust theologies of Israel and Judaism. In this thesis, I seek to elucidate the conceptual relationship between these two elements—each theologian’s early engagement with Barth and their later contributions to post-Holocaust theology. My analysis reveals that these three theologians all critique Barth’s doctrine of God’s self-determination as the pre-determination of the identity of Israel and Judaism to be witnesses of God’s judgment. This critique enables each of the three to articulate a more positive account of Israel’s and rabbinic Judaism’s witness.


title: Surviving the Present: A Study of the Role That Human/Animal Difference Plays in Jacques Derrida’s Writings

contributor:
Enns, Diane
Philosophy

subject: deconstruction; human/animal difference; Jacques Derrida; post-human ethics; survival

abstract:
This dissertation answers three questions relating to Jacques Derrida’s writings: why is Derrida concerned with human/animal difference? How should his deconstruction of this distinction be understood in the context of his broader philosophical project? Finally, do the answers to these questions complicate the belief that Derrida’s thought promotes a post-human ethics? Whereas Derrida’s sensitivity to the suffering of non-human creatures partially explains his interest in “the animal,” there are complex reasons for why he frequently returns to interrogate this theme–reasons that can only be understood by first clarifying core features of his philosophy. I maintain that what obsesses Derrida in virtually all of his writings is how a longstanding,
“metaphysical” view of human consciousness proves deconstructable. Following Derrida, I term this view “living presence”–the belief that experience happens presently to beings who are present
to themselves. In undermining this view, Derrida reimagines experience as what I term “survival,” where the very things traditionally thought to be foreign to human subjective life are required for experience to carry on happening.
Importantly, the fact that philosophers repeatedly describe human consciousness in terms of presence is not simply an error. It is rather an effort to preserve the living present against the threat that everything opposed to presence plays in its very possibility. This explains why human/animal difference is so strenuously affirmed throughout the history of Western thought on Derrida’s view. Animals are not simply inferior kinds of beings compared to humans; there is rather thought to be an essential difference between the two. Whereas humans encounter themselves and their world presently, animal are utterly instinctual, reactional, and non-present to themselves. However, by deconstructing the human/animal distinction, Derrida reveals that those features traditionally associated with animals are necessary for any life, human or otherwise, to exist. For this reason, “the animal” is a “pharmakon”: it both sustains and upsets a long-held
understanding of what we uniquely are.
In my final analysis, I examine whether my reading of Derrida’s thought is compatible with a non-human ethics. I do so in two steps: first, I examine a prominent reading of Derrida’s thought that contends that it is. For a large number of thinkers in “animal studies,” Derrida’s thought is aligned with the philosophy Emmanuel Levinas in important respects: whereas Derrida rejects Levinas’ anthropocentrism, he retains the core of Levinas’ ethics. However, I argue that the conditions that Derrida believes make life possible undermine this reading of his work. In the end, I argue that if deconstruction is an ethics, it is so only because it promotes “life” understood in the sense developed in this dissertation. Yet we must be mindful of what deconstruction does not provide in the way of an ethics: on the one hand, any standard of ethical belief is deconstructible. On the other hand, deconstruction does not necessarily promote a more inclusive and compassionate future. Whereas it can do so, it might also inaugurate a future that is less inclusive and more savage. This is, I argue, precisely what cannot be known.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Violence, Colonialism & The Third World Woman: A Postcolonial Discourse Analysis on Violence Against South Asian Women

contributor:
Joseph, Ameil
Social Work

subject:
Postcolonialism
Violence Against Women
Discourse Analysis
South Asia

abstract: Intimate partner violence impacts women around the world and therefore does not present itself congruently across cultures or regions (Devries et al., 2013; Sarkar, 2010; World Health Organization, 2012). Many contemporary researchers strive to name, classify and understand experiences of intimate partner violence that are distinct to the South Asian subcontinent and members of the South Asian diaspora (Ahmed-Ghosh, 2004; Bloch & Rao, 2002; Chatterji & Chaudhry, 2014; Jeyaseelan et al., 2007; Mani, 1987; Panchanadeswaran, & Koverola, 2005). Their works contribute to a dominant discourse about violence against South Asian women that often frames cultural understandings and practices to be the cause of harm within this community. A dominant discourse which predominantly utilizes Western feminist understandings of “patriarchy” and oppression primarily serves to further homogenize, Other, and essentialize the experiences of South Asian women which cannot and should not be discussed in contrast to violence in a Western context. The impact of applying a Western lens to violence against South Asian women is that Western scholars take on the responsibility of identifying and prioritizing the needs of South Asian peoples and offer solutions to these issues without considering the systems of support that already exist or asking those impacted how they imagine change. This project engages a postcolonial discourse analysis to examine dominant discourses on violence against South Asian women as they are deployed within the context, literature, and research on intimate partner violence. Through analyzing 75 highly cited articles using a postcolonial lens, this project unearths commonalities across the dominant discourse such as the use of positivistic colonial research methods, the construction of a monolithic South Asia, the technologies of neoliberalism and colonial capitalism, and the archetype of the Third World Woman via white feminism. These reoccurring themes throughout the dominant discourse indicate the existence of an inferiorizing and oversimplified understanding of South Asian people and their experiences which is frequently framed using colonial technologies and the white gaze. Deconstructing these mechanisms can create an intentional space for anti-colonial ways of being and knowing as a South Asian person and discussions of violence in the South Asian subcontinent and diaspora without essentializing, homogenizing, or erasing aspects of these experiences.

abstract: Thesis

abstract: Master of Social Work (MSW)


title: Improving Calcium Carbonate Based Porous Media for Lateral Flow Assays

title: CALCIUM CARBONATE BASED POROUS MEDIA

contributor:
Pelton, Robert
Filipe, Carlos
Chemical Engineering

subject:
Calcium Carbonate
Lateral Flow Assays
Porous Media
Printable Materials

abstract: Nitrocellulose is currently the most common porous material used in commercially available lateral flow assays. It is, however, unsafe to manufacture and time consuming to incorporate into multi-component assay devices. Precipitated calcium carbonate is a material produced from naturally occurring lime that can be suspended in a binder and extruded onto a surface. This extruded suspension forms a porous coating through which a solution can be wicked. The physical characteristics of three different types of calcium carbonate types were investigated to determine differences that may yield better lateral flow. The capillary flow rate through the coating was found to be largely affected by the calcium carbonate type used, the binder concentration and whether any post-printing treatment was applied, specifically heating the print. Calcium carbonate has a high specific surface area, which results in a high protein binding capacity. To prevent protein binding, pre-treating calcium carbonate particles prior to forming the suspension in a binder was attempted. Pre-treatment with bovine serum albumin, casein or methoxy-PEG phosphate did not show prevention of protein binding. Furthermore, by treating the calcium carbonate particles with a protein before suspension formulation, the wicking rate after printing was found to be diminished.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Trait-based Approaches In Aquatic Ecology

contributor:
Kolasa, Jurek
Biology

subject:
aquatic ecology
parameter estimation

abstract: Ecologists try to understand how changing habitats alter the populations of organisms living within them, and how, in turn, these changing populations alter the environment. By linking individual or cellular (physiological) processes to system level responses, mechanistic models can help describe the feedback loops between organisms and the environment. Aquatic systems have long used mechanistic models, but increasing model complexity over the last 50 years has led to difficulty in parameterization. In fact, it is often unclear how researchers are choosing parameters at all, even though small changes in parameters can change qualitative predictions. I explore the challenges in parameter estimation present in even an ideal situation. Specifically, I conduct individual experiments for all of the needed parameters to describe a simple lab-based, aquatic system; estimate those parameters using the results from these experiments supplemented with literature data; and run a large experiment designed to test how well the lab-estimated parameters predict actual zooplankton populations and nutrient changes over time. I document best practices for finding and reporting parameter choices and show whole ecosystem level consequences of a variety of decisions. To get the best predictions I find that a mix of parameter estimation methods are necessary. Trait-based approaches are another method to understand species-environment interactions. Trait-based methods aggregate species into functional traits, perhaps making qualitative predictions easier. Theory suggests that more functionally diverse systems will be more resilient. I test this prediction in a simple aquatic system but am unable to find consistent support for this hypothesis, and instead finding that results are highly dependent on what measures of ecosystem recovery are used. Overall, more species-specific information is critical to building better models for both mechanistic and trait-based approaches.  I expand species-specific data by providing new information, and collating information from literature on a small, tropical Cladocera.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Predicting what will happen to a habitat after a disturbance is critical for conservation and management. Species specific information is useful for building a mechanistic understanding of ecology.  Predictions that include underlying processes (mechanisms) may be more robust to  a changing environment than predictions based on correlations. Eutrophication, the addition of excess nutrients, is a common problem in freshwater habitats. Being able to predict the effects of nutrient addition is critical for ensuring the health of freshwater ecosystems. By using species-specific life history and morphological information and a simple lab system, I test different methods of predicting and understanding the consequences of eutrophication. I find that the ramifications of eutrophication are not easily predicted by species' categorizations or with a more detailed mechanistic model.


title: Rate-Power Trade-Off in Solar Cell-based Simultaneous Lightwave Information and Power Transfer Systems

contributor:
Hranilovic, Steve
Electrical and Computer Engineering

subject:
Visible Light Communication
Power Harvesting

abstract:
The Internet-of-Things (IoT) infrastructure is made of uniquely identifiable wireless-enabled smart devices that use the Internet to communicate with each other as well as people, on a large scale. These IoT devices require power to operate, and to communicate with other smart devices. The optical bands have the capacity to provide power and wireless communication to the IoT devices.

Simultaneous lightwave information and power transmission (SLIPT) is a technology through which information and optical power are received simultaneously by the receiver. SLIPT is made possible by solar cell-based SLIPT receivers. In this thesis, for the first time, the trade-off between the achievable data rate and the harvested power in solar cell-based SLIPT systems is quantified and analysed.

It is known that the amount of power harvested using a solar cell is dependent on its operating voltage.
By utilizing a realistic electrical model of the solar cells, an expression for the bandwidth and a lower bound on the data rate of a solar cell receiver as function of the operating voltage is derived. Using the dependency of rate and power on the operating voltage, the rate-power trade-off in solar cell based SLIPT receivers are studied in this thesis.

This work proposes a novel solar cell based SLIPT receiver that includes a DC-DC boost converter, which allows control over the operating voltage of the solar cell.
Finally, this thesis proposes an optimization problem to compute the optimum operating voltage for a SLIPT system located indoor where a desired trade-off between the data rate and harvested power can be attained based on the battery state of charge.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: The Investigation of Temporal Order in Language Learning Using Behavioural Tasks and MMN

contributor:
Service, Elisabet
Cognitive Science of Language

subject:
Serial Order
Temporal Order
Short-Term Memory
MMN
Word Learning
Repetition Tasks

abstract:
Short-term memory (STM) has demonstrated to be affected by serial order, involving the use of rhythm and entrainment to stimuli. However, less is known of the extent of this relationship and language learning, and the literature focuses on words rather than sentences. Moreover, the literature lacks an exploration of whether this relationship has a correlation with MMN responses.
We had 30 participants (21 female) complete two sentence repetition tasks, a temporal rhythm accuracy task, and two temporal order judgment tasks. We also recorded the electroencephalograms (EEG) from 24 of the participants (17 female) while they listened to syllables differing by time of presentation and differing by consonant and vowel. We then correlated performance on these tasks to performance on a foreign-word learning (FWL) task. We hypothesized that the STM tasks would predict performance in the FWL task, and we explored whether temporal accuracy and word learning correlated with MMN responses to early stimuli. We found that only the foreign sentence repetition task significantly predicted performance in the FWL task. We also did not find any significant correlations with MMN responses and temporal accuracy and word learning abilities. Findings show that with previous exposure to a novel language, the prosodic pattern of the foreign language is stored temporarily in STM, which enhances learning of the foreign words. Further exploration is needed to understand the relationship of temporal order and language learning with cortical responses.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Spoken language is driven by rhythm and keeping track of this rhythm allows us to keep track of the order in which sounds in language are presented. Remembering the order of items requires the use of short-term memory. The better one is at repeating back the order of items, the better they are at learning new words. This thesis investigates the relationship between various short-term memory tasks (English nonword sentence repetition task, foreign sentence repetition task, temporal rhythm accuracy task, auditory judgment task, visual judgment task) and foreign-word learning. This thesis also explores whether there is a correlation between one’s brain responses to differing stimuli and a person’s ability to track the timing and order of items, as well as a person’s ability to learn new words. The results reveal that only the foreign sentence repetition task, using the same foreign language as the word learning task, significantly predicts one’s ability to accurately learn foreign words. The results did not show any significant interaction between one’s neural responses and rhythm or word learning. These results suggest that the ability to maintain the order of items in memory aids word learning, but further exploration is required with regards to non-verbal stimuli and neural responses. It is important to investigate individual differences in repetition tasks that require short-term memory, as this will aid in understanding normal language development and language acquisition.


title: Evidence Synthesis and Evaluation in Nutrition

abstract: Chronic non-communicable diseases affect a large proportion of the population and are associated with significant morbidity, mortality, and social and economic impact. Large cohort and modelling studies estimate that a substantial proportion of these conditions can be attributed to dietary habits. Clinicians, guideline developers, policymakers, and researchers use systematic reviews that address the relationship between dietary exposures and health outcomes to advise the public on optimal dietary habits, formulate recommendations and policies, and plan future research. A growing body of evidence, however, suggests that there are serious problems with current methods for evidence synthesis and evaluation in nutrition, examples of which include overreliance on expert opinion and consensus, failure to follow standard systematic review methods, and the application of inconsistent criteria for the assessment of the certainty of evidence. These issues have led to ineffective (at best) or harmful (at worst) dietary recommendations and policies and the proliferation of research that cannot be confidently applied to guide dietary decisions. The objective of this thesis is to advance methods for evidence synthesis and evaluation in nutrition. The thesis begins by reviewing contemporary challenges in evidence synthesis and evaluation for dietary guideline development and offering novel insight on opportunities for future improvement. The thesis subsequently provides a descriptive analysis of limitations of recently published systematic reviews and meta-analyses of nutritional epidemiology studies. This thesis then presents two systematic reviews and meta-analyses addressing the health effects of red and processed meat consumption that serve as examples of the application of rigorous systematic review methods in nutrition. This thesis ends by describing opportunities and challenges for future evidence synthesis and evaluation in nutrition.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: Assessment of Healthy Colonic Motility Patterns, Colonic Dysmotility, and its Association with Autonomic Nervous System Dysfunction

contributor:
Huizinga, Jan D.
Health Sciences

subject: colonic motility

subject: high resolution colonic manometry

subject: high amplitude propagating pressure waves

subject: human colon

subject: functional motility disorders

subject: gastroenterology

abstract: Introduction: Functional motility disorders of the colon are poorly defined. Hence, patients with chronic colonic motor dysfunction are treated or undergo surgery without proper diagnosis. Most colonic motility assessment centers around the largest propagating motor pattern in the colon- the High Amplitude Propagating Pressure Wave (HAPW). However, there is no consensus regarding a definition of this important motor pattern. Additionally, no consideration is given to other aspects of colonic motility such as colo-ano-rectal coordination and control by the autonomic nervous system (ANS). The aim of this thesis was to improve understanding of HAPWs and other features of colonic motility in health and constipation, understand how autonomic dysfunction is related to observations in patients, and evaluate the effect of neuromodulation of the ANS. Methods: Motility was assessed in healthy volunteers and patients using water-perfused High Resolution Colonic Manometry (HRCM). To assess the association between ANS and colonic motor activity Heart Rate Variability (HRV) was measured in patients. Spatiotemporal maps were created using HRCM to analyse and quantify colonic motor activity following baseline, and interventions which included proximal balloon distention, meal, and rectal bisacodyl. Low-Level Light Therapy (LLLT) was also applied during HRCM as a method of neuromodulation, to observe its effect on colonic motility. Results: Normal HAPWs are those which have an amplitude of more than 50 mmHg and belong to one of 3 categories: proximally originating, proximal continuing, and transverse/descending. The best intervention sequence to generate these during HRCM assessment is baseline, proximal balloon distention, meal, rectal bisacodyl. Based on their responses to these interventions and the type of HAPWs present, patients could be classified into strong responder, weak responder and non-responder groups. Overall, patients in the strong responder group were most similar to healthy volunteers both with regard to motility and ANS control. Conversely, the weak and non-responders had showed decreased or no motility with decreased parasympathetic input and occasionally sympathetic inhibition. Additionally, other features of motility such as the sphincter of O'Beirne, and lack of colo-ano-rectal coordination were found to lead to constipation even in presence of normal HAPWs. LLLT shows promise in initiating colonic motor activity through neuromodulation of the sacral defecation center. Conclusions: HAPWs can be defined into one of three categories and used to categorize patients based on their HAPW response to different interventions. However, other aspects of colonic motility such as the colo-ano-rectal coordination and autonomic nervous system control of colonic motility should be taken into consideration in diagnosis of constipation, as they can point towards more non-invasive treatment methods such as neuromodulation using LLLT.

abstract: Thesis

abstract: Master of Science in Medical Sciences (MSMS)


title: A cup above: Production and distribution of Ionian cups in the chora of Metaponto

contributor:
Pope, Spencer
Classics

abstract: This thesis analyzes examples of a specific class of Greek pottery from the ancient city of Metaponto. ‘Ionian cups’ were common in the Late Archaic period across the Greek world. As a result, a well-established typology exists for these vessels, allowing them to be dated with considerable accuracy. This study identifies the type and date of Ionian cups from the ‘chora’ or countryside of Metaponto. This information is then used to date sites found in the countryside through archaeological survey. By studying a single class of pottery with a narrow chronological window, it is possible to assess the occupation and development of the chora through the lens of pottery analysis. Examining the distribution of Ionian cups in the countryside reveals that the Greeks preferred sites with high elevation, good soil, and plentiful water. Access to cultivable land drove the settlement of the landscape more than proximity to the city center. This pattern of occupation indicates that a mixture of cereal-based agriculture and pastoralism were practiced in the 6th century with considerable success. Sites with Ionian cups were among the most prosperous in the countryside, marking a distinct stage in the city’s development. Investigation of this material has facilitated understanding of how the Greeks lived in the countryside, and how they exploited the landscape.

abstract: Thesis

abstract: Master of Arts (MA)


title: Three Essays on the Ethics and Effects of Public Policy on the Price-Accessibility of Pharmaceuticals

contributor:
Longo, Christopher
Health Policy

subject: pharmaceuticals pricing ethics opioids cancer access drugs utilization

abstract:
Pharmaceuticals have become, arguably, one of the fastest changing forms of health care. Advancements in pharmaceuticals are constantly bringing better treatments to illnesses previously untreatable. These advancements, however, come with a hefty price tag: In many countries they also represent the fastest growing source of health care expenditures. Innovative drugs often come to the market with high prices, and the prices of existing drugs can creep up if they are not reined in. These high prices can threaten patient access to the pharmaceuticals they need. Fortunately, there is a lot public policy can do, if it is designed to interact well with clinical, economic, and commercial factors, to safeguard this access.

This thesis contains three studies on the effects of public policy on the price-accessibility of pharmaceuticals. Its objectives are as follows: 1) To develop the definitions of a fair pricing of pharmaceuticals in terms of price-accessibility, 2) to present two case studies where public policy changes pharmaceutical prices and affects their utilization, and 3) discuss the significance of these case study policies on access to these drugs.

This thesis contributes to the existing body of literature by developing new theoretical models about what constitutes fair pricing of pharmaceuticals and about the relationships between the main parties responsible for making pharmaceuticals accessible to the people who need them. A new evaluation of the policy that delisted high-strength opioids from public formularies in Ontario is also presented with new regression models that allow the analysis of the effects of the policy across sociodemographic categories. Finally, this thesis also contains the first empirical analysis of OHIP plus, the policy that extended the public drug benefits to all individuals under 25 years of age; in this case, with the focus on oral chemotherapy drugs for cancer.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: The rising prices of some pharmaceuticals have made them inaccessible to patients and their families, who must make big financial sacrifices to afford the drugs they need. This thesis contains three studies on the impact of ethical pricing and public policy on the accessibility of pharmaceuticals. Its objectives are to develop definitions of fair pricing in terms of access, to analyze two public policies that sought to change the utilization of pharmaceuticals by changing the price people pay for them, and to elaborate on what these policies mean for the accessibility of these drugs. This thesis’ contributions to the literature include novel theoretical models about pharmaceutical pricing and new evaluations of the effects, by sociodemographic category, of a policy designed to combat the ongoing opioids epidemic in Ontario, Canada, and the effects of OHIP plus on the emerging use of expensive oral-delivery cancer drugs in the same province.


title: Serial Order in Language Learning in Bilinguals

subject:
Serial Order
Working Memory
Phonological Short-Term Memory
Non-linguistic Short-Term Memory
Language Rhythm
Foreign Word Learning Aptitude

abstract: The current thesis has two aims to further the understanding of the cognitive underpinnings that are involved in word-learning and language processing. One aim is to  understand how individuals are able to make temporary phonological and serial order representations of new words in language and non-language domains. The second aim is to investigate whether the mechanisms involved in maintaining temporary nonverbal and serial order representations are related to verbal short-term abilities. We created four behavioural tasks to determine the processing of phonological short-term memory information, nonverbal short-term memory information, serial order short-term memory information and rhythmic short-term memory. We used 30 adult Spanish-English bilinguals as the target population to also investigate whether individual language abilities in two spoken languages affect the learning of words in a foreign language with distinct prosody and phonology.  The first correlational analysis revealed that performance on a serially ordered verbal short-term memory task that involved a language of unfamiliar prosody and phonology was strongly predicted by performance on two serially ordered verbal short-term memory tasks that involved languages of familiar prosody and phonology. A second correlational analysis showed that tasks that tapped into individuals’ memory for serial order in the verbal, nonverbal and rhythmic domains were weakly associated with one another. In a third correlational analysis, it was shown that individuals’ lexical knowledge of Spanish was not a predictor of their performance on a measure of their serially ordered verbal short-term memory abilities. Multiple linear regression analyses found that none of the tasks that were used to measure individuals’ abilities for processing serial order information in the verbal, nonverbal and rhythmic domain were strong predictors for foreign-word learning. Overall, the results show promising findings for the tasks that tapped into serial order short-term memory for verbal information. However, they also suggest that the nonverbal and rhythm tasks may not be reliable measures of the constructs we were hoping to study. Future work should adjust the tasks to ensure we are properly tapping into individuals’ serial order abilities in the nonverbal and rhythm domains.

abstract: Thesis

abstract: Master of Science (MSc)


title: Investigating the Role of Type I IFNs in OSM-Mediated Pulmonary Inflammation

contributor: Medical Sciences (Molecular Virology and Immunology Program)

subject:
gp130 cytokines
Pulmonary Inflammation
Interferons
Adenovirus

abstract:
Immune responses during lung infections must be tightly regulated in order to permit pathogen eradication while maintaining organ function. Although mechanisms involve complex networks of cytokines, the interferon (IFN) response has been shown to be an important driver of lung inflammation. Type I IFNs consist of a group of structurally similar cytokines that are produced during virus infection and are an integral part in regulating the immune response. However, in response to certain stimuli, type I IFNs have also been found to be central in the initiation of lung inflammatory responses by inducing the recruitment and activation of immune cells and thus may contribute to disease severity. Another cytokine that has been associated with chronic lung inflammation is the gp130 cytokine, Oncostatin M. Transient pulmonary overexpression of Oncostatin M by Adenovirus vector (AdOSM) induces lung inflammation biased toward Th2 cytokines associated with eosinophilia and alternatively activated (AA/M2) macrophage accumulation. Here we demonstrated that C57Bl/6 mice deficient of the type I interferon receptor (IFNAR1-/-), were less responsive against a suboptimal dose of AdOSM at day 7 post infection compared to AdOSM-treated wild-type. We observed a significant reduction in OSM mRNA and protein levels in AdOSM-treated IFNAR1-/- mice, compared to treated wild-type, which resulted in significant attenuation in OSM-induced inflammatory cell infiltration, epithelial hyperplasia, and alveolar wall thickening. Furthermore, IL-6 overexpression (as a comparator gp130 cytokine), induced lymphocyte accumulation in IFNAR1-/- mice, but at significantly lower levels than AdIL-6-treated wild-type. These results demonstrate that cross talk between IFNAR and gp130 cytokine signaling were required for maximal AdOSM- and AdIL-6-mediated pulmonary inflammation.
We also observed that IFNAR1 deficiency directly and negatively regulated OSM-mediated responses in vitro. OSM-induced pSTAT3 levels were consistently lower in murine and human IFNAR1-deficient fibroblasts, compared to OSM-stimulated wild-type cells. This was associated with diminished OSM-induced IL-6 and MCP-1 production from IFNAR1-/- fibroblasts. Furthermore, we found that the combination of OSM and IFN-α led to increased IL-6 production from C57Bl/6 and BALB/c-derived Mouse Lung Fibroblasts (MLFs) then when either cytokine was used alone suggesting that these two cytokines can work in concert. Our findings are the first to suggest that IFNAR signaling participates in OSM-mediated responses in vitro and is required for maximal AdOSM-induced pulmonary inflammation in vivo.

abstract: Thesis

abstract: Master of Science (MSc)


title: New Routes to Functional Silicone Elastomers Through Sulfur Chemistry

contributor:
Brook, Michael A.
Chemistry and Chemical Biology

subject:
silicones
thiol-ene reactions
redox reversible linkages
Piers-Rubinsztajn reactions
used tire recycling
thermoplastic silicones

abstract: Silicones elastomers are widely used all over the world due to their unusual properties when compared to their carbon-based counterparts. Synthetic methods for their synthesis are still quite limited and the traditional silicone products are not able to completely meet the requirement for modern materials. Silicone elastomers with customized structures and with higher levels of sustainability will be the research focus for the development of next generation materials. The element sulfur and its functional groups are growing players in modern polymer and materials science, since sulfur reactions are exceptionally versatile. The incorporation of sulfur reactions into the design and preparation of silicone materials can lead to silicones with unique properties for various research interests. Initial exploration was focused on the creation of general and simple methods for 3D printing silicone elastomers using thiol-ene chemistry. However, silicone inks suitable for 3D printing are still quite limited. Photo-initiated thiol-ene chemistry was proposed to design a rapid cure silicone ink for extrusion 3D printing. Unlike other radical reactions, the relatively oxygen insensitive thiol-ene was able to provide the necessary rapid reaction rate and build up the necessary viscosity for practical printing in less than 2 seconds in the presence of air. Various customized silicone structures with different moduli were obtained with a relative fast printing speed. The use of thiol oxidation reactions in the synthesis of silicone elastomers is also demonstrated in this thesis. Reductive cleavage of the resulting disulfide bridge was successfully performed with the presence of hydrosilane and B(C6F5)3 catalyst. Herein, a synthetic method to reversible silicone elastomers based on the disulfide linkage is described. This method could be extended to cleave the disulfide and polysulfide linkage in used automotive rubber materials. Various kinds of sulfur-cured rubbers were successfully devulcanized to polymeric oil. This simple and efficient method could potentially offer a solution for the huge amount of tire waste produced every year. Finally, a new method for preparing thermoplastic silicone elastomers with ionic linkages is reported. A novel dicarboxylic acid-modified silicone was synthesized though thiol-Michael additions. The resulting ionic crosslinked networks were built though the neutralization between carboxylic and amino silicone. Thermoplastic silicone elastomers with unique viscoelastic behavior can be obtained. In summary, the thesis demonstrates that sulfur chemistry is an exceptional synthetic tool for the silicone chemist.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Ecohydrological controls of natural and restored lichen and moss CO2 exchange on a rock barrens landscape

contributor:
Waddington, James Michael
Earth and Environmental Sciences

subject:
Lichen
Moss
CO2 exchange
Turtle nesting
Rock barrens

abstract: Lichen and moss are the dominant ground cover on the Canadian Shield rock barrens of eastern Georgian Bay, and they provide many ecosystem services. Lichen and moss mats are essential for developing and accumulating soil on the bedrock landscape, and as the mats establish they moderate soil temperature and reduce soil water losses, thereby improving the microclimate for more complex vegetation. In addition to pioneering ecosystem succession, the lichen and moss mats provide essential nesting habitat for turtle species-at-risk. These lichen and moss mats are not well understood on rock barrens landscapes, and as such this thesis aims to increase knowledge of the growth, persistence and restoration approaches for these valuable ecosystem resources. We quantified the ecohydrological controls on the growth of lichen and moss mats by measuring the CO2 exchange of lichen and moss under varying environmental conditions. From these results we determined that key growth periods for lichen and moss were during the wet portions of the growing season (spring and fall), and that growth was limited or non-existent during the dry period (summer). Further, we determined that soil moisture was the most important control on lichen and moss CO2 exchange, and that this relationship differed among cover type (lichen, moss, mix of lichen and moss). Moss was able to continue CO2 uptake at a lower water content than lichen, suggesting that lichen would have a greater decline in productivity under drier conditions. A decline in lichen and moss productivity would also likely lead to a decline in soil development through chemical weathering which, in turn, could affect the availability of turtle nesting habitat. We also used CO2 exchange measurements to compare lichen and moss productivity between natural and transplanted mats. Transplanting in-tact patches of lichen and moss has not been widely studied, and as such we tested this approach on a rock barrens landscape. We determined that natural and transplant productivity did not differ for lichen, and that there were some differences between treatments for mixed and moss plots. We also used the tea bag index method to compare relative decomposition rates between treatments (natural, transplant), where we found that decomposition rates did not differ. Our results indicate that it is feasible to remove lichen mats from the footprint of a planned disturbance such as construction and transplant them successfully to nearby undisturbed areas. This approach would restore the lichen cover and the ecosystem services that lichens provide immediately rather than waiting decades for natural regrowth or fragment establishment. As a whole, this thesis will increase knowledge of both the growth and persistence, as well as the restoration of lichen and moss on rock barrens landscapes. Given that lichens and mosses of these genera grow globally, our findings can be applied widely to enhance and protect lichen and moss mats, and the ecosystem services they provide

abstract: Thesis

abstract: Master of Science (MSc)


title: Regulation of Interferon Stimulated Genes Following Enveloped Virus Entry and Delivery of Viral Nucleic Acid

subject:
Virus
Innate immunity
Interferon
Pattern recognition

abstract:
Innate antiviral defence depends on virus recognition and cytokines like interferon (IFN) that upregulate many interferon-stimulated genes (ISGs). Virus recognition normally relies on pattern recognition receptors binding to virus-associated nucleic acid motifs, but virus activity may provide an additional means for the cell to recognize infection. Enveloped viruses fuse with a cell membrane during entry and membrane fusion by virus-like particles or the purified protein p14 are sufficient to upregulate ISGs in the absence of viral nucleic acid. This thesis examines the mechanism by which cells recognize membrane fusion and how this affects downstream signalling and upregulation of ISGs.
We found that membrane perturbation by enveloped virus particles or p14 triggered cytosolic Ca2+ oscillations important for antiviral defence. Surprisingly, Ca2+ signalling seemed to act upstream of nucleic acid sensing pathways during enveloped virus infection. In the absence of viral nucleic acid, p14 triggered a Ca2+-dependent antiviral response to dsRNA. It is still unclear how p14 might trigger recognition of endogenous dsRNA.
We found that enveloped virus particles trigger IRF3-mediated upregulation of interferon as well as direct IFN-independent upregulation of ISGs. Furthermore, while some viruses like HCMV trigger widespread IRF3 activation, other viruses like SeV upregulate IRF3 and IFN in a minority of infected cells. This disparate response to infection can lead to different biological outcomes when measured at the population level.
Our work highlights the complexity of the response to enveloped virus particles, despite the absence of replication. Further work is necessary to understand how membrane perturbation is recognized and how this interfaces with nucleic acid sensing. While nucleic acid sensing is sufficient to upregulate antiviral ISGs, other signals like membrane perturbation may provide important contextual cues during infection. This will be important to understand moving forward as virus-like particles are used more and more for research and clinical applications.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract:
Cells rely on pattern recognition receptors for innate antiviral defence. While the study of pattern recognition has focused on virus-associated nucleic acid motifs, disruptions of the cellular environment during virus infection could similarly warn the cell. Membrane perturbation during enveloped virus entry is associated with upregulation of antiviral interferon-stimulated genes. This thesis examines the mechanism of membrane perturbation sensing and different antiviral signalling pathways activated by non-replicating enveloped virus particles.
We found evidence that membrane perturbation triggers cytosolic Ca2+ signalling which may act as a co-stimulatory signal for recognition of incoming viral nucleic acid. We initially thought enveloped virus particles were recognized through a common pathway, but have since learned that recognition is more complex. Further work is necessary to understand how membrane perturbation and nucleic acid sensing interface during enveloped virus infection and what role this plays in antiviral defence.


title: Three Essays in Inference and Computational Problems in Econometrics

contributor:
Shin, Youngki
Economics

subject:
model averaging
cross validation
mixed integer programming
semiparametric estimation
threshold model
synthetic control estimation
maximum rank correlation

abstract:
This dissertation is organized into three independent chapters. In Chapter 1, I consider the selection of weights for averaging a set of threshold models. Existing model averaging literature primarily focuses on averaging linear models, I consider threshold regression models. The theory I developed in that chapter demonstrates that the proposed jackknife model averaging estimator achieves asymptotic optimality when the set of candidate models are all misspecified threshold models. The simulations study demonstrates that the jackknife model averaging estimator achieves the lowest mean squared error when contrasted against other model selection and model averaging methods.
    In Chapter 2, I propose a model averaging framework for the synthetic control method of Abadie and Gardeazabal (2003) and Abadie et al. (2010). The proposed estimator serves a twofold purpose.
First, it reduces the bias in estimating the weights each member of the donor pool receives. Secondly, it accounts for model uncertainty for the program evaluation estimation. I study two variations of
the model, one where model weights are derived by solving a cross-validation quadratic program and another where each candidate model receives equal weights. Next, I show how to apply the placebo study and the conformal inference procedure for both versions of my estimator. With a simulation study, I reveal that the superior performance of the proposed procedure.
    In Chapter 3, which is co-authored with my advisor Professor Youngki Shin, we provide an exact computation algorithm for the maximum rank correlation estimator using the mixed integer programming (MIP) approach. We construct a new constrained optimization problem by transforming all indicator functions into binary parameters to be estimated and show that the transformation is equivalent to the original problem. Using a modern MIP solver, we apply the proposed method to an empirical example and Monte Carlo simulations. The results show that the proposed algorithm performs better than the existing alternatives.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Singularity Formation in the Deterministic and Stochastic Fractional Burgers Equations

contributor:
Protas, Bartosz
Mathematics

subject: Burgers equation; blow up; singularities; enstrophy; width of the analyticity strip; stochastic PDE

abstract: Motivated by the results concerning the regularity of solutions to the fractional Navier-Stokes system and questions about the influence of noise on the formation of singularities in hydrodynamic models, we have explored these two problems in the context of the fractional 1D Burgers equation. First, we performed highly accurate numerical computations to characterize the dependence of the blow-up time on the the fractional dissipation exponent in the supercritical regime. The problem was solved numerically using a pseudospectral method where integration in time was performed using a hybrid method combining the Crank-Nicolson and a three-step Runge-Kutta techniques. A highlight of this approach is automated resolution refinement. The blow-up time was estimated based on the time evolution of the enstrophy (H1 seminorm) and the width of the analyticity strip. The consistency of the obtained blow-up times was verified in the limiting cases. In the second part of the thesis we considered the fractional Burgers equation in the presence of suitably colored additive noise. This problem was solved using a stochastic Runge-Kutta method where the stochastic effects were approximated using a Monte-Carlo method. Statistic analysis of ensembles of stochastic solutions obtained for different noise magnitudes indicates that as the noise amplitude increases the distribution of blow-up times becomes non-Gaussian. In particular, while for increasing noise levels the mean blow-up time is reduced as compared to the deterministic case, solutions with increased existence time also become more likely.

abstract: Thesis

abstract: Master of Science (MSc)


title: Feasibility Study on Conducting a Subcritical Molten Salt Reactor Experiment Using a DD Neutron Source

title: Evaluation of Different Reactivity Measurement Methods

contributor:
Buijs, Adriaan
Engineering Physics

subject:
Nuclear Energy
Molten Salt Reactor
Experiment
Subcritical Pile
Reactivity Measurement
Engineering Design Process
Feasibility
Neutronic Analysis
Serpent Monte-Carlo Reactor Physic Code

abstract: Over the last two decades, there has been widespread international interest in the development of the molten salt reactor concept due to its passive safety, high coolant boiling temperature, low operational pressure, high thermal efficiency, and ease of breeding.   Terrestrial Energy Incorporated (TEI) is developing a thermal-spectrum converter type molten salt reactor, called the Integral Molten Salt Reactor (IMSR-400) to be built by 2030. A physics experiment is needed in order to validate the theoretical predictions of the temperature reactivity coefficients of the IMSR-400. This thesis will determine the feasibility of conducting a subcritical experiment, utilizing a Deuterium-Deuterium Fusion Neutron Source (DD).

abstract: Thesis

abstract: Master of Science (MSc)


title: The bull as a numismatic type in Magna Graecia, from Archaic to Late Classical Period

subject: coinage classics

abstract:
This paper attempts to explore the potential cultural role of the bull as a numismatic motif in Magna Graecia from the Archaic to the Classical Period, focusing on how the bull associates with the cultural and political identities of different groups. It starts from the reverted bull of Sybaris, discussing the link between the bull and the collective Sybarite identity in the region through analyzing archeological, numismatic, and literary evidence. The paper then explores the cultural significance of various alterations of the bull in communities succeeding Sybaris after 510 BCE. This provides us a glimpse concerning how the Sybarites, after losing the city, understanding the Sybarite identity. The paper further turns to the butting bull, which became a constant emblem of a new political entity, Thurium. Regardless of the possible Sybarite influence, the butting bull seems to specifically link with the mercenary group. This link was further consolidated at the end of the fifth century when this type spread and rooted in Sicily with the establishment of mercenary settlements. This paper examines the distribution of the butting in Sicily from the end of the fifth century to the middle of the fourth century and discusses how this motif may link with the mercenary in each site. But gradually, the militaristic character of the butting bull was diluted as the mercenary settlement developed into a more proper state. In general, the bull as a numismatic type experienced a dynamic process of changes. These changes do not merely refer to stylistic and ichnographic change, but also the change in its cultural implications. It is thus a barometer reflecting the self-identification of diverse population groups and the interactions of various communities in Magna Graecia.
I appreciate the help and concern from my committee members and my families, without which I cannot finish this paper.

abstract: Thesis

abstract: Master of Arts (MA)


title: Investigation of Transition Metal Alkyl, Allyl, Hydride, and Borohydride Complexes as Potential Precursors for Atomic Layer Deposition

contributor:
Emslie, David
Chemistry and Chemical Biology

abstract:
The bulk of this work focuses on the syntheses of various transition metal
complexes bearing alkyl, allyl, hydride, and borohydride ligands, as well as the evaluation
of these complexes as potential new chemical precursors for the ALD of mainly
electropositive transition metals.
The compounds bearing alkyl ligands which were investigated are
[Cr(CH2SiMe3)4] (1), [Cr(CH2CMe3)4] (2), [V(CH2SiMe3)4] (3), [W2(CH2SiMe3)6] (5),
[Mo2(CH2SiMe3)6] (6), and [Cr(dmpe)2(Me)2] (7). Syntheses for complexes 1–3 and 5–7
have previously been published, but this work will introduce alternate or slightly modified
procedures, as well as the description of the solid-state structure of 3. Each complex was
shown to sublime without decomposition. Thermal stability studies revealed that the
complexes lacked the thermal stability on a long timescale to be effective as ALD
precursors in a typical ALD reactor, assuming that a delivery temperature 40 °C higher
than the sublimation temperature at 5 mTorr will be required. The vanadium containing
complex [{V(CH2SiMe3)3O}2Mg(dme)2] (4) was isolated as an intermediate during the
synthesis of 3 and structurally characterized by single crystal X-ray diffraction.
Additionally, homoleptic allyl complexes [M{1,3-bis(trimethylsilyl)allyl}2] M =
Ni (8), Cr (9), Co (10) were investigated. The solution state reactivity of each complex
towards the potential co-reactants AlEt3, BEt3, and PhSiH3 was examined. Promising
reactivity was observed between complex 8 and AlEt3, as well as complex 10 and AlEt3 or
complex 10 and PhSiH3. However, subsequent study of the thermal stability of each
complex revealed decomposition of each complex 40 °C above the sublimation
temperature. Nickel complex 8 thermally decomposed to yield nickel metal (as analyzed
by powder X-ray diffraction), and as such is suggested as a candidate for nickel metal
chemical vapour deposition, contingent upon characterization of the minor unidentified
reflection observed during powder X-ray diffraction.
Borohydride complex [(dmpe)2Mn(μ-H)2BH2] (11) was obtained through the
reaction of [(dmpe)MnH(C2H4)] with BH3(NMe3). The complex sublimes without
decomposition at 80 °C, but was shown to undergo thermal decomposition after being
heated to 120 °C, lacking the desired thermal stability for ALD use. Complexes
[{(dmpe)2MnH}2(μ-dmpe)] (12) and [(dmpe)2MnH(κ1-dmpe)] (13) were identified in
crude reaction mixtures during the synthesis of 11, and were subsequently synthesized
independently. The synthetic scheme for 13 was extended to [(dmpe)2MnH(PMe3)] (14),
and both complexes were crystallographically characterized. Compounds 12–14 exist in
solution as isomers with cis- or trans- disposed hydride and κ1-PR3 ligands. For each complex, isomerization from trans- to cis- was shown to be photochemically induced,
while the reverse isomerization will take place either slowly (days) in the absence of light,
or quickly (hours) through heating. Manganese compound 14 was shown to be volatile at
60 °C and to only undergo moderate decomposition after being heated to 100 °C.

abstract: Thesis

abstract: Master of Science (MSc)


title: Design and systems-level performance analysis of petroleum coke conversion strategies

contributor:
Adams II, Thomas
Chemical Engineering

abstract:
Petroleum coke (petcoke) is a solid waste product of crude oil refinery operations with disposal issues. Therefore, this thesis focuses on systems level performance analysis of design configurations by which petcoke can be disposed of in the most environmentally benign and cost-competitive pathway. In the systems evaluated, we explored the environmental and cost benefits of utilizing the energy stored in the refinery solid waste (petcoke) to produce liquid
transportation fuels and electricity. Specifically, we proposed petcoke as a feed to produce liquid fuels via Fischer-Tropsch synthesis. For power generation, we explored the performance of petcoke in an integrated gasification combined cycle (IGCC) and oxy-combustion technology. To minimize greenhouse gas (GHG) emissions, carbon capture and sequestration (CCS) were implemented in some of the designs allowing further performance analysis of the variants of the designs which were operated with and without CCS.
In the petcoke to liquid fuels study, three design strategies that operated with and without CCS namely petroleum coke standalone gasification (PSG), petroleum coke gasification integrated natural gas reforming (PG-INGR), and petroleum coke gasification external natural gas reforming (PG-ENGR) were proposed. To compare the performance of the designs, performance metrics such as fuel and thermal efficiencies, net present value, minimum diesel selling price, and direct CO2 emissions were employed. Overall, the PG-INGR design outperformed the other designs and showed to be a feasible candidate design for petcoke to liquids process.
Subsequently, a cradle-to-grave environmental life cycle impact assessment of a petcoke derived diesel for a functional unit of 1 km distance driven in a diesel-powered vehicle was investigated for two possible locations in Canada: Ontario and Alberta provinces. These petcoke processes were compared to the conventional crude oil and oil sands derived diesel processes. In terms of GHG emissions, the results showed that there was no clear superior design amongst the three CCS enabled processes for the plants located in Ontario, but they outperformed the conventional crude oil and oil sands derived diesel processes.When the cost of CO2 avoided (CCA) was factored into the analysis for the petcoke processes, the PG-INGR design had lower costs and thus confirms it as the viable design to adapt for liquids production.
Exploring the benefits of a waste source of fuel, the techno-economic and life cycle analysis (LCA) of petcoke was further examined in the IGCC power plant operated with CCS. This design performance was compared against the coal based IGCC and supercritical pulverized coal (SCPC) power plants operated with CCS of the same net power output based on its levelized cost of electricity, thermal efficiency, feed consumption rate, and direct GHG emissions. Results showed that the petcoke power plant outperformed both reference systems in both economics and environmental impacts.
Finally, petcoke was further explored as fuel in the oxy-combustion power plant designed to operate with and without carbon capture and sequestration. Our study of the oxy-combustion power plant further included the purification of the captured CO2 stream via cryogenic distillation to meet pipeline specifications. This analysis was to compare its performance to that of petcoke IGCC power plant. LCA and CCA of the petcoke oxy-combustion power plant designs were also presented. Overall, the results showed a cost-competitive source of electricity generation even for the design with highly purified CO2. In terms of environmental impacts, the LCA study confirmed the minimal emission tendency of the petcoke oxy-combustion system even when the indirect petcoke emissions were considered.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Radiative alpha capture on 7Be with DRAGON at νp–process nucleosynthesis energies

contributor:
Chen, Alan
Physics and Astronomy

subject:
nuclear astrophysics
recoil separators
radioactive ion beams
reaction networks
explosive nucleosynthesis
nuclear physics
supernovae

abstract:
A possible mechanism to explain the origin of around 35 neutron–deficient stable isotopes with mass A≥75 between 74 Se and 196 Hg, known as the p–nuclei is the nucleosynthesis in the proton–rich neutrino–driven winds of core–collapse supernovae via the νp–process. However this production scenario is very sensitive to the underlying supernova dynamics and the nuclear physics input. As far as nuclear uncertainties are concerned, the breakout reaction from the pp-chains, 7Be(α, γ)11C, has been identified
as an important link which can influence the nuclear flow and therefore the efficiency of the νp–process. However its reaction rate is not well known over the relevant energy range (T9 = 1.5–3).
In this thesis we report on the direct first measurement of two resonances of the 7Be(α, γ)11 C reaction with previously unknown strengths using an intense radioactive 7Be beam from ISAC and the DRAGON recoil separator in inverse kinematics.
Since resonance strength measurements with low mass beams using recoil separators depend strongly on the recoil angular distribution, which can exceed the acceptance of the separator, we first performed a proof–of–principle test by measuring a known resonance of the 6Li(α, γ)10B reaction, which also presents a similar challenge.
Our results from the 6Li(α, γ)10B reaction are in agreement with literature, showing that DRAGON can measure resonance strengths of reactions for which the maximum momentum cone of the recoils exceeds its acceptance. From the newly measured 7Be(α, γ)11C resonance strengths we calculated the
new reaction rate which is lower than the current recommended by 10–50% and constrained to 5–10% in the relevant temperature region. Using this new rate, we performed detailed nucleosynthesis calculations which suggest that there is no effect the production of light p–nuclei, but a production increase for CNO elements of up to an order of magnitude is observed.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Mitochondria as a critical nexus point in mediating THC-induced trophoblast dysfunction: An in vitro study

subject: Placenta Cannabis Delta-9-tetrahydrocannabinol Mitochondria Trophoblasts

abstract:
The etiology of many gestational disorders is still unknown.  However, insufficient trans-placental passage of nutrients and wastes due to poor placentation is characteristic of several pathologies and may be due, in part, to altered function of placental mitochondria.  Mitochondrial activity is essential in pregnancy because it sustains the metabolic activity of the placenta throughout gestation.  Exposure to stressors that perturb processes governing placentation, including maternal drug use, can negatively impact fetal development.
Cannabis use is prevalent during pregnancy.  The psychoactive constituent, delta-9-tetrahydrocannbinol (THC), can cross the placenta to affect placental and fetal physiology.  Importantly, cannabinoid receptors have been reported on trophoblast cells, and on mitochondria which are abundant in placentae.  It has been reported that THC may target the mitochondria in various tissue types, including placental tissue, and alter its function.  However, few studies have addressed the physiological control of mitochondria within the placenta, an organ that is critical for fetal growth and pregnancy maintenance.
I investigated the role of mitochondria in trophoblast differentiation and syncytialization using rotenone, a complex I inhibitor.  Subsequently, I investigated the role of THC on two important aspects of placentation – invasion and syncytialization – using placental trophoblast cells HTR8/SVneo and BeWo, respectively.  In response to rotenone and THC, there was increased ROS production, oxidative stress, and altered transcriptional markers favouring mitochondrial fragmentation.  Treatment with 20µM THC for 48 hours led to reduced mitochondrial respiration, ATP production and loss of mitochondrial membrane polarity.  Critically, these THC-induced mitochondrial changes occurred concomitant with evidence of reduced trophoblast invasion and syncytialization.  Furthermore, THC exposure reduced levels of human chorionic gonadotropin, human placental lactogen and insulin-like growth factor 2, which are growth factors necessary for fetal development.  Placental mitochondrial dysfunction, particularly when THC-induced, may be critical in a range of gestational disorders which have important implications for maternal and fetal/offspring health.

abstract: Dissertation

abstract: Doctor of Philosophy (Medical Science)

abstract: Cannabis is commonly used by pregnant women.  Fetal exposure to cannabis and its components can impair fetal growth and neurological development.  These negative fetal outcomes may be the result of poor placental formation, due to placental cell exposure to cannabis and its psychoactive component, delta-9-tetrahydrocannabinol (THC).  Importantly, THC can also target intracellular organelles, like the mitochondria which are known as the “powerhouses” of the cell.  Few studies have investigated the direct effects of THC on placental development.  The purpose of this study was to determine how THC exposure to placental cells may alter their function.  We found that THC impaired processes that allow placental attachment to the uterus and form a protective barrier, and compromised mitochondrial function, which are important for placental formation.  These findings serve to inform scientists and doctors, thus stimulating the creation of new ideas and methods to further explore the impact of THC on pregnancy outcomes.


title: Connecting the Observed Properties of Exoplanet Populations to Their Formation

contributor:
Pudritz, Ralph
Physics and Astronomy

abstract: The wealth of exoplanetary data as displayed on the mass-semimajor axis and mass-radius distributions reveal a tremendous amount of information constraining our understanding of their formation. We link the variety of outcomes shown in exoplanet populations to the observed ranges of protoplanetary disk properties using the core accretion model of planet formation. For this purpose, we consider a population synthesis framework that samples disk properties' observationally-constrained distributions as inputs to thousands of planet formation models. Planet traps are a key feature of our approach in that they are barriers to rapid type-I migration, and are sites of early stages of the core accretion process in our models. We show that a low setting of forming planets' atmospheric envelope opacities $\kappa_{\rm{env}}\simeq10^{-3}$ cm$^2$ g$^{-1}$ is necessary to achieve a range of gas giants' orbital radii that agrees with the data. At this low setting of $\kappa_{\rm{env}}$, X-ray ionization and its related dead zone results in a clear separation between hot Jupiters and warm gas giants near 1 AU. When radial dust drift is included in our models, the rapid migration of solids into the ice line makes it a crucial trap for the formation of super Earths and warm gas giants. The ratio of the formation frequency of these two planet types has an interesting dependence on the initial disk radius $R_0$, with intermediate $R_0\simeq$50 AU producing the largest super Earth population, and both larger and smaller disk sizes forming more gas giants. When including disk chemistry, the range of disk radii over which planet formation in traps occurs leads to a wide range of solid compositions, from ice rich planets (up to 50\% ice by mass) to dry, Earth-like compositions. We show planet compositions and post-disk atmospheric photoevaporation to be two key factors affecting the mass-radius distribution of our populations.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Bariatric surgery alters the gut microbiota and blood glucose in mice

contributor:
Schertzer, Jonathan D.
Biochemistry

subject:
bariatric surgery
gut microbiota
diabetes
blood glucose

abstract: The prevalence of obesity is increasing globally. Obesity is characterized by increased fat mass and is a risk factor for type 2 diabetes (T2D). Obesity is associated with hyperglycaemia, hyperinsulinemia, insulin resistance and chronic inflammation. Currently, the most effective and durable treatment for obesity and its comorbidities is bariatric surgery. Bariatric surgery changes food intake, energy balance and the composition of gut microbiota. Bariatric surgery can lower blood glucose and put T2D into remission. It was unknown if bariatric surgery-induced changes in the gut microbiota was an independent yet sufficient factor to lower blood glucose. Fecal microbiota transplantation (FMT) was performed on conventional (specific-pathogen-free, SPF) and germ-free (GF) mice using fecal material obtained from patients before surgery and 12 months after bariatric surgery. We tested FMT into mice from the same patients before and after vertical sleeve gastrectomy (VSL) and biliopancreatic diversion with duodenal switch (BPD/DS). FMT did not alter body weight, fat mass, glucose tolerance or glucose transporter mRNA expression in all intestine segments in SPF mice. FMT lowered blood glucose during an oral glucose load in GF mice receiving bacteria after VSL and BPD/DS bariatric surgery. Post-BPD/DS surgery FMT decreased Glut1 transcript level in the ileum and increased Glut1 transcript level in the TA muscle of GF mice, but did not change GLUT1 protein levels. Post-BPD/DS surgery FMT also decreased goblet cell count, villus height and crypt depth in the ileum of GF mice. We conclude that changes in the gut microbiota caused by bariatric surgery is a standalone factor that can lower blood glucose and alter gut morphology.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Type 2 diabetes is a chronic disease that involves high blood sugar (i.e. glucose), which can damage many parts of the body leading to serious complications. Diabetes is a growing global problem and is the seventh leading cause of death. Obesity is one of the largest factors leading to type 2 diabetes. Bariatric surgery reduces obesity and is to date the most effective method to lower blood glucose and reverse type 2 diabetes. Bariatric surgery alters gut anatomy and the types of bacteria that inhabit the gut. Gut bacteria can change obesity and blood glucose levels, but it was not known if the bacterial community present after bariatric surgery was a factor that is sufficient to lower blood glucose. We found that transferring gut bacteria from humans after bariatric surgery into mice lowers the blood glucose and alters the gut barrier structure where food is absorbed. It is not yet clear how this happens, but these findings show that a change in gut microbes is a standalone factor that can alter host blood glucose. Finding the glucose lowering factor in bacteria may be a new treatment to combat type 2 diabetes.


title: Investigating the role of the intestinal microbiota in unhealthy aging

title: Unhealthy aging and the microbiota

contributor:
Bowdish, Dawn
Medical Sciences

subject: Microbiome Frailty Aging Sacropenia Inflammation Colonization

abstract: Chronic systemic inflammation increases with age and is associated with late life diseases (e.g. sarcopenia, and frailty) but the mechanisms causing systemic inflammation are largely unknown. Our laboratory has shown that the aged microbiome increases intestinal permeability which allows bacterial products into the circulation, thus causing systemic inflammation. We do not, however, know which microbes drive this phenomenon and ultimately impact healthy or unhealthy aging. To determine the degree to which frailty, sarcopenia, and systemic inflammation can be accelerated or exacerbated via the microbiome, we colonized germfree (recipient) mice with ‘young’ (≤6 months) or ‘old’ (≥ 18 months) microbiota from specific pathogen free mice. Initially, we investigated the impact of recipient age by colonizing young and old germfree mice. Differences in sarcopenia and cellular inflammation were driven by recipient age, not microbiota age, after 6 weeks of colonization, while frailty decreased in old mice colonized with young microbiota. To further investigate the impact of the microbiota in aging, we colonized middle-aged (10-14 month) germfree mice and assessed them 6 weeks and 6 months post colonization. The aged microbiota drove an increase in frailty after 6 months of colonization. To understand the differences between young and old microbial compositions we quantified short-chain fatty acids and sequenced 16S rRNA from fecal pellets of young and old mice. We used frailty, sarcopenia, and cellular inflammation data to identify relationships with short-chain fatty acids and the microbial community. We have identified specific microbes that correlate with age, frailty, sarcopenia, and cellular inflammation from Lachnospiraceae, Akkermansiaceae and Rikenellaceae families. By understanding the role of the microbiome in healthy and unhealthy aging we can develop therapeutics to combat chronic systemic inflammation and prevent and/or reverse poor health outcomes.

abstract: Thesis

abstract: Master of Science (MSc)


title: The Use of Bioorthogonal Chemistry to Create 99mTc and Micelle-based Diagnostic Agents

contributor:
Valliant, John F.
Chemical Biology

abstract:
Technetium-99m (99mTc) radiopharmaceuticals are widely used in nuclear medicine to diagnose a variety of diseases, including cancer. While, 99mTc is a seemingly ideal radioisotope for imaging, there is an incompatibility between the isotope’s half-life (6 h)  and the biological half-life of antibodies (multiple days), which are useful and prevalent targeting vectors. This misalignment in physical half-life and pharmacokinetics creates a  barrier to the development of molecularly targeted 99mTc-based radiopharmaceuticals. To address this,  bioorthogonal chemistry between tetrazine and trans-cyclooctene (TCO) derivatives labelled with 99mTc and a variety of different targeting molecules was explored to assess the feasibility of using pre-targeting versus conventional direct labeling strategies.
Initially, a new family of tridentate chelate 99mTc-tetrazine ligands of varying polarity were synthesized and characterized. The 99mTc-tetrazine ligands were evaluated in vivo for bone targeting through a pre-targeting strategy with a (TCO)-functionalized bisphosphonate: TCO-BP. The hydrophobic 99mTc-tetrazine derivative demonstrated targeted shoulder and knee uptake of 4.62 ± 1.36 and 9.12 ± 1.88 % ID/g, respectively, in biodistribution studies at 6 h post injection. At the same time point, accumulation of the hydrophilic 99mTc-tetrazine derivative in the shoulder (2.10 ± 0.38 % ID/g) and knee (3.15 ± 0.33 % ID/g) joints, albeit to a lesser degree,  is further evidence of successful targeting of 99mTc-tetrazine ligands to a TCO-tagged site in vivo.
Next, the 99mTc-tetrazine ligands were evaluated in vivo in tumour xenografts through a pre-targeting strategy with a TCO-modified antibody targeting the A33 antigen in colon carcinomas. Biodistribution studies were performed using SPECT-CT imaging and tissue counting following necropsy. Unfortunately, low tumour uptake (~ 1 % ID/g) was observed for both the hydrophobic and hydrophilic 99mTc-tetrazine derivatives tested. The current hypothesis is that significant uptake in metabolizing organs, notably the liver and intestines, and short blood circulation time of the tetrazine ligands limited the coupling between the two components.
To explore the impact of drug formulation on the distribution and accessibility of radiolabelled tetrazines, Pluronic F127 polymeric micelles were used where encapsulation was designed to modify the pharmacokinetics of the hydrophobic 99mTc-tetrazine. The micelles significantly increased the blood circulation time of the 99mTc-tetrazine while also significantly reducing liver uptake. Unfortunately, this did not translate into increased bone uptake of the encapsulated 99mTc-tetrazine when evaluated with the TCO-BP targeting vector through a pre-targeting strategy. This is likely because the tetrazine is not preferentially released at the sites with the high TCO-BP concentration.
The micelles used in the initial study were non-targeted. To capitalize on the chemistry developed during the preparation of the 99mTc-tetrazines, the Pluronic F127 polymers previously used for encapsulation were modified with terminal TCO groups, creating a simple way of modifying the surface of micelles with targeting vectors. A F127-TCO polymer was synthesized in high yield and the corresponding micelles were visualized by DLS and TEM to be 20-25 nm in size. A bisphosphonate-derived tetrazine (TzBP) was prepared and radiolabelled with 99mTc and combined with the TCO-modified micelles to create a new class of targeted micelles. In vitro, active and pre-targeting studies showed the F127-TCO micelles preferentially bound to the hydroxyapatite salt in the presence of TzBP compared to controls. In vivo, F127-TCO micelles accumulated at bone at a 7-fold higher concentration when modified with [99mTc]TcTzBP compared to that seen when labelled with a non-targeted tetrazine. This approach ultimately represents a platform for the creation of targeted micelle encapsulated drugs.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: Exploring male university students’ perspectives of sexual violence prevention

contributor:
Greene, Saara
Social Work

subject:
masculinity
sexual violence
feminist theory
prevention
gender
qualitative
critical masculinity studies

abstract:
Emerging anti-violence work has focused on the importance of engaging men in primary
prevention efforts, especially on postsecondary campuses, due to the statistical reality that men are overrepresented as perpetrators of sexual violence (Black et al, 2011; Piccigallo, Lilley, & Miller, 2012; Flood, 2019). This study sought to build upon this existing body of literature by inviting male university students into discussions around their perspectives of sexual violence prevention efforts on campus to better understand how prevention programming can be improved to elicit male student engagement. Six participants were recruited from McMaster University to participate in focus groups. Focus groups begun with the facilitation of a common activity used in anti-violence programming, titled “the gender boxes,” to contextualize the discussion around exploring the social construction of gender as it intersects with violence against women. The ensuing discussion revealed the following themes: (1) cisheteropatriarchal masculinity demands men perform gender in ways that recreate sexual scripts and traditional gender roles, as evidenced by their reflections on “the gender boxes” activity, (2) traditional masculinity intentionally obscures the dynamics of negotiating sex and consent, which subsequently create the potential for sexual violence to occur, (3) participants described feeling disengaged from existing prevention efforts, and (4) participants imagined potential improvements to engage men in sexual violence prevention, which largely reflected existing literature on the subject. This project contributes to anti-violence efforts through revealing the continued need to engage men in every stage of the process to then facilitate their investment in ending violence against women.

abstract: Thesis

abstract: Master of Social Work (MSW)


title: Purification of Semiconducting and Metallic Single-Walled Carbon Nanotubes Using Conjugated Polymers

contributor:
Adronov, Alex
Chemistry and Chemical Biology

subject:
Organic Chemistry
Carbon Nanotubes
Purification
Metallic
Semiconducting
Characterization
Conjugated Polymers

abstract:
Single-walled carbon nanotubes (SWNTs) have attracted extensive research effort
since their discovery nearly 30 years ago. Their impressive mechanical, optical, thermal,
and electronic properties make them promising candidates for incorporation into a variety
of applications. Depending on the method used for SWNT synthesis, different diameter
ranges can be produced. Within these diameter ranges, a heterogeneous mixture of
semiconducting and metallic species are present. The combination of these electronic
species, as well as their minimal solubility in common solvents, hinders their incorporation
into electronic devices, providing reasons for the development of scalable purification
techniques. Although, some impactful purification strategies have been developed in recent
literature, the use of conjugated polymers is considerably more scalable, less expensive,
and offers processability of the final purified material. At the time of this thesis, the
purification of semiconducting SWNTs has been realized using electron-rich conjugated
polymers such as polyfluorenes, polycarbazoles, and polythiophenes. For metallic SWNTs,
less progress has been made. When enriched, metallic SWNTs could act as an effective
replacement for common metals in conductive applications. The objective of this work is to develop an efficient and scalable technique for the dispersion of metallic SWNTs and to shed light on the effect of polymer electronics on SWNT dispersion selectivity using nitrated poly(fluorene-co-phenylene)s and cationic poly(fluorene-co-pyridine)s. These investigations lead to the development of novel techniques using multiple conjugated polymers to yield enriched metallic SWNT samples. A secondary objective of this work is to investigate the gentle removal of the polymer, post-purification using UV-irradiation to cleave the polymer linkages of a poly(carbazole-co-terephthalate). Characterization of the polymer-SWNT composites is carried out using absorbance, photoluminescence, and Raman spectroscopy techniques to evaluate their electronic purity.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Transcriptome profiling of Eutrema salsugineum under low phosphate and low sulfur

contributor:
Weretilnyk, Elizabeth
Golding, G. Brian
Biology

subject:
Eutrema
Bioinformatics
Genomics
RNA-seq
Phosphate starvation

abstract:
Improving the efficiency by which crops use nutrients is critical for maintaining high crop productivity while reducing fertility management costs and eutrophication related to fertilizer
runoff. The native crucifer and halophyte, Yukon Eutrema salsugineum, was used in this study.
Yukon E. salsugineum is closely related to important Brassica crops and thrives in its native
habitat on soil that is low in available phosphate (Pi) and high in sulfur (S). To determine how
Yukon E. salsugineum copes with low Pi, leaf transcriptomes were prepared from four week-old plants grown in controlled environment chambers using soil lacking or supplemented with Pi and/or S. This thesis focused on using bioinformatic approaches to assemble, analyze and
compare the transcriptome profiles produced by the Yukon E. salsugineum plants undergoing
four nutrient combinations of high and/or low Pi and S. The objective of the study was to
identify traits associated with altered S and/or Pi with the prediction based on other species
that low Pi, in particular, would pose the greatest stress and hence elicit the greatest transcriptional reprogramming. Transcriptome libraries were generated from four treatment
groups with three biological replicates each. Reads in each library were mapped to 23,578 genes in the E. salsugineum transcriptome with an average unique read mapping ratio of 99.52%. Surprisingly, pairwise comparisons of the transcriptomes showed little evidence of Pi-responsive reprogramming whereas treatments differing in soil S content showed a clear S-responsive transcriptome profile. Principal Component Analysis revealed that the low variance quaternary Principal Component distinguished the transcriptomes of plants undergoing low versus high Pi treatments with differential gene expression analysis only finding 11 Pi-responsive genes. This outcome suggests that leaf transcriptomes of Yukon E. salsugineum plants under low Pi are largely undifferentiated from plants provided with Pi and is consistent with Yukon E. salsugineum maintaining Pi homeostasis through fine-tuning the expression of protein-coding and non-coding RNA rather than large-scale transcriptomic reprogramming. Previous research has shown Yukon E. salsugineum to be very efficient in its use of Pi and this work suggests that the altered expression of relatively few genes may be needed to develop Pi-efficient crops to sustain the crop demand of a growing population.

abstract: Thesis

abstract: Master of Science (MSc)


title: Family eating behaviours and child body mass index: Changes after 12 months enrolment in a pediatric weight management program

contributor:
Morrison, Katherine
Medical Sciences

subject:
eating behaviours
body mass index
eating style
eating related to hunger
weight management
pediatric

abstract:
Background: Overweight and obesity affect approximately one-third of Canadian children and these children are at an increased risk of developing life-long obesity-related health consequences. Treatment efforts in the pediatric setting focus on behavioural modification – including modification of dietary intake. Eating behaviours encompass a modifiable aspect of dietary intake and could be a useful approach for weight reduction in the context of pediatric weight management (PWM) programs.
Objectives: 1) To describe changes in family, child and parent eating behaviours over a 12-month period after enrolment in a PWM program. 2) To examine if changes in family eating behaviours over the first 6 months in a PWM program can predict child BMI z-score at 12 months, even when controlling for other factors related to changes in BMI z-score.
Methods:  Children ages 2-17 with a BMI >85th percentile were included in this analysis. Data was collected at baseline, 6 month and 12-month timepoints as part of the CANadian Pediatric Weight management Registry. BMI z-score was derived from height (cm) and weight (kg). Eating behaviours (eating related to hunger (ERH) and eating style (ES)) were measured in children, parents and families using the Family Eating and Activity Habits Questionnaire. Child and parental scores were summed to generate a family score. Decrease in scores over time indicated improvements in eating behaviours.
Results: 807 children were included in the analysis (48.3% male, 51.7% female, mean age 12.08, mean baseline BMI z-score 3.55). Family ERH scores decreased significantly from baseline to 6 months by 1.63% (-0.16 points, SD=0.09, p<0.05) but by 12 months scores were the same as at baseline. Child ERH scores decreased significantly by 2.06% at 6 months (-0.14 points, SD=0.02, p<0.05), but at 12 months scores were the same as at baseline. Parent ERH scores did not change significantly. Family ES scores decreased from baseline to 6 months by 1.88% (-1.99 points, SD=0.21, p<0.05) and stayed approximately the same at 12 months. Child ES scores were similar, decreasing 2.86% (-1.68 points, SD=0.03, p<0.05) from baseline to 12 months. Parents ES score decreased significantly by 6 months, but after 12 months, scores were the same as at baseline. Change in either family eating behaviours from baseline to 6 months did not predict child BMI z-score at 12 months when adjusting for age, sex and BMI z-score at baseline. In subsequent exploratory analysis, increases in child eating behaviour scores at 6 months was a significant predictor of increases in child BMI z-score at 12 months (p=0.02) when adjusting for age, sex and BMI z-score at baseline.
Conclusion: In the context of PWM programs, eating style and eating for hunger improved over the first 6 months after enrolment. Improvements in child eating behaviour after 6 months could predict improvements in child BMI z-score after 12 months.

abstract: Thesis

abstract: Master of Science (MSc)


title: Examining Ribonucleases and G-quadruplex Binding Proteins as Regulators of Gene Expression in S. venezuelae

contributor:
Elliot, Marie
Biology

subject:
Microbiology
Gene Regulation
Molecular Genetics

abstract: Controlling when genes are expressed is critical for the growth of an organism. Studying gene expression regulation in Streptomyces presents an opportunity to better understand how these complex bacteria develop and how they control their impressive biosynthetic capabilities. In this work we investigated the potential role of a G-quadruplex binding protein, and two ribonucleases (RNases) in regulating gene expression in Streptomyces venezuelae. G-quadruplexes are structures that form in DNA or RNA molecules. Depending on their location in DNA, G-quadruplexes can increase or decrease the expression of nearby genes and the stability of a G-quadruplex structure can be affected by G-quadruplex binding proteins. We probed the ability of a G-quadruplex-associated protein from S. venezuelae, TrmB (a tRNA-methyltransferase), to bind and methylate G-quadruplexes and prevent the formation of these structures. We were unable to conclude that TrmB bound or methylated G-quadruplex structures or motifs. RNases are enzymes that cleave RNA molecules and have important roles in controlling cellular RNA levels, and thus gene expression. We  investigated the roles of RNase J and RNase III in S. venezuelae. Both of these RNases impact development and specialized metabolism in Streptomyces. We found that the RNase J mutant was unable to grow properly on classical medium containing glycerol. We also documented small RNA fragments that were unique to the RNase J mutant and sought to identify them. To better understand the RNase J and RNase III strains, we conducted RNA-sequencing of wild type S. venezuelae and mutant strains lacking RNase III or RNase J. Comparisons between each mutant and the wild type strain revealed significant changes in genes related to nitrogen assimilation, phosphate uptake, and specialized metabolite production in both the RNase III and RNase J mutant. Together these results contribute to our understanding of the diverse regulatory features that exist in S. venezuelae.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Studying how gene expression is regulated in the Gram-positive, soil-dwelling bacteria Streptomyces presents an opportunity to better understand how these complex organisms develop and how they control their impressive biosynthetic capabilities. This study investigated the potential role of a G-quadruplex binding protein, and two ribonucleases (RNases) in regulating gene expression in Streptomyces venezuelae. We probed the ability of a G-quadruplex associated protein from S. venezuelae, TrmB, to bind, methylate, and prevent the formation of G-quadruplex structures in DNA. We also investigated the roles of RNase J and RNase III in S. venezuelae growth and development. In RNase J and RNase III mutants, RNA-sequencing revealed dramatic changes in the transcript levels of genes related to phosphate uptake, nitrogen assimilation, and specialized metabolite production. Together these results contribute to our understanding of the diverse and complex regulatory features that exist in S. venezuelae.


title: Ghana, World, and Future: Translocality and National Development for Pan-Africanism, 1957-1968

contributor:
Ibhawoh, Bonny
History

subject:
Ghana
Pan-Africanism
Translocality
Development
Global Political Economy
Decolonization

abstract: As former colonies and newly independent states of the ‘Third World’ organized internationally around anticolonialism in the 1950s and 1960s, Ghana became a key site in debates over development at the height of the Cold War. Contributing to the new economic and political history of postcolonial Ghana, this study examines the national development visions and international political-economic connections of the Nkrumaist state 1957-66 and the first year under the post-coup National Liberation Council through the lens of translocality. Translocality refers to the entanglement of different localities and communities, and in this context, how the idea and practice of national development is co-constituted with these connections. Kwame Nkrumah situated national development as a resource in uniting the African continent against foreign political and economic influence. The Nkrumaist state played a leading role in the formation of the Organization of African Unity, non-alignment, nuclear non-proliferation, and attempts at harmonizing national development continentally. The movements of individuals to Ghana seeking participation within the Nkrumaist project were also racialized and gendered. Women Pan-Africanist activists organized conferences and made internationalist commentaries, making claims for inclusive economic development and participation. Furthermore, Ghanaian national development, dependent on mixed-planning foreign capital, markets, and technologies to finance projects, became increasingly subject to non-national departmental debates and an emerging liberal disciplinary politics through 1962-1966. The International Monetary Fund, Britain and the United States came to a consensus regarding a balance of payments and foreign reserve crisis in Ghana. After a military coup d'état in 1966, the NLC introduced an IMF reform package and embarked on a program of unmaking Nkrumaism. This study contributes to understanding the translocal dynamics of postcolonial development and development discourses.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: I argue that Ghana’s national development from 1957 to 1968 was conceived of, practiced, and situated within, transnational and international connections that can be best understood through the concept of translocality. Translocality refers to the entanglement of different localities and communities, and in this context, how the idea and practice of development cannot be separated from these relational connections. The research supporting this concept contributes to understanding African postcolonial national development in tension and co-constituted with non-national dynamics. As an idea and policy mandate dictated by Kwame Nkrumah, national development was defined as a resource in the struggle for Pan-Africanism but also entangled with the politics of Pan-Africanism, the Cold War and international creditors. These translocal connections are explored through the activisms and commentaries of women Pan-Africanists, activists, and political moderates travelling to Ghana as well as the formal Pan-African diplomacies in pursuit of the economic unification of Africa. Ghana’s development future was also subject to the interdepartmental politics of international creditors and an emerging liberal economic consensus. This study is necessary because it changes our understanding of how the politics of postcolonial development is understood, as co-constituted with non-national political, economic and social dynamics.