identifier: Xu, Yixin  (2020) The Impact of Natural Disasters on the Performance and Solvency of U.S. Banks.  Masters thesis, Concordia University.

abstract: This paper explores the effect of natural disasters on the profitability and solvency of U.S. banks. Employing a sample of 187 large-scale natural disasters that occurred in the U.S. between 2000 and 2014 and a sample of 2,891 banks, we find that natural disasters have a pronounced effect on the net-income-to-assets and the net-income-to-equity ratio of banks, as well as impaired loans and the return on average assets. We also observe significant effects on the equity ratio and the tier-1 capital ratio (two solvency measures). Interestingly, the latter are positive for regional banks which appear to voluntarily increase their capital reserves in response to natural disasters that affect part of their operations, but significantly negative for banks that operate locally or nationally.


identifier: Bhatt, Aditya Kumar ORCID: https://orcid.org/0000-0003-1005-7740 <https://orcid.org/0000-0003-1005-7740>  (2020) Voltage Source Converter based Hybrid STATCOM for Reactive Power Compensation in Utility Grid.  Masters thesis, Concordia University.

type: Thesis NonPeerReviewed

abstract:
The availability of high voltage, high current and high-speed power electronic devices has led to increase in popularity of several power electronic applications such as FACTS. A STATCOM is one such power electronic converter, from the FACTS family, which can be used to improve the power factor of a transmission line, maintain the connected bus at the required voltage level, etc. In distribution power level, D-STATCOMs are used to achieve the same objectives. Several power converter topologies have been proposed for STATCOMs and D-STATCOMs, ranging from a standard two-level VSC based topology to a cascaded full-bridge based topology. The cascaded full-bridge based topology might be suitable for high power STATCOM applications but might not be the best option at the lower power level of a D-STATCOM. D-STATCOMs therefore often use a standard two-level converter-based topology owing to cost constraints.
The research work presented in this thesis proposes a new power electronic topology which can be used for D-STATCOM applications. This topology is essentially composed of multiple cascaded h-bridge cells in each phase of a standard two-level converter. The two-level converter provides bulk of the power output and operates at a low switching frequency, whereas the h-bridge cell operates at a higher switching frequency and achieve power quality objectives. This research work initially presents simulations to validate the proposed topology. Outer control is proposed to operate the proposed topology as a D-STATCOM. Inner control loops are proposed to maintain the DC-link voltage of the h-bridge cells. An experimental prototype of the proposed topology is also developed. The results obtained from the proposed topology are compared with that obtained from a standard two-level converter-based topology. It is shown that due to the h-bridge cell action in the proposed topology, the obtained current THD is low in comparison to a standard two-level VSC based topology being used as a D-STATCOM.


identifier: Switzer, Andrew Clark, Caldwell, Warren, da Estrela, Chelsea and Gouin, Jean-Philippe  (2020) From Me to You: Stress Spillover and Respiratory Sinus Arrhythmia.  Masters thesis, Concordia University.

creator:
Switzer, Andrew Clark
Caldwell, Warren
da Estrela, Chelsea
Gouin, Jean-Philippe

abstract: Stress spillover describes how stress in one life domain affects other life domains. For example, parenting stress, defined as stress related to raising a child, tends to affect how romantic partners think about, feel, and behave in their romantic relationship with their spouse. Evidence suggests that, on average, parents of young children experience a decline in romantic relationship quality as they transition into parenthood. However, not all parents experience stress spillover from their child-related stress to their romantic relationship. This study evaluated whether respiratory sinus arrhythmia, a biomarker of emotion regulation capabilities in interpersonal relationships, moderates the effect of child-related stress on marital stress among parents of young children. As part of a dyadic study, 82 cohabiting couples raising preschool aged children had their resting RSA assessed during a laboratory visit, and independently reported on their daily child-related stress and marital stress for seven consecutive days. Actor partner interdependence modelling tested the associations between child-related and marital stress for both members of the couple, as well as the moderating role of each partners’ RSA. Results indicated significant actor and partner effects of child-related stress on actor marital stress. These results show that one partner’s reports of child-related stress were related to their own reports of marital stress and to their partner’s reports of marital stress, even after adjusting for their partner’s reports of child-related stress, indicating the presence of a stress spillover effect. Furthermore, a significant interaction between partner’s reports of child-related stress and partner’s RSA when predicting actor’s marital stress revealed that this stress spillover effect was larger among individuals with lower RSA. Our findings suggest that RSA influences the extent to which parenting stress impacts one’s interpersonal behaviours in their romantic relationship.


identifier: Zhou, Yujie  (2020) Not a Simple 'Anthropocene' Story in Contemporary China: Unveiling the Entanglement of Chinese Social and Environmental Issues.  Masters thesis, Concordia University.

abstract:
I developed this thesis, that addresses current social issues and environmental issues in contemporary China, in response to the pursuit of economic development and urbanization, before and after the political-ideological reorientation of the Chinese Communist Party led by Deng Xiaoping and his Reform and Openness policy at the end of the 1970s. I explore the cinematic reflection of environmental problems and social issues in three films of Jia Zhangke, a famous sixth-generation director who adopts realistic aesthetic and artistic pursuit in his films. My reflection is accompanied by a critical discourse analysis of newspaper articles from People’s Daily. Through these two methods, I examine the reality of contemporary China through an economic, cultural, political, social and natural lens to shed light on the root causes of various social and environmental issues in contemporary China.
Guided by Anthropocene thinking, I engage in a discussion on tensions within human- nature relationships in China. This research introduces a way of understanding the human- nature relationship within the Anthropocene framework by considering elements including the social structure of human society, the social stratification of different social groups, and the ultimate hegemony of powerholders. In this thesis, I argue that proletariats and ordinary Chinese people in contemporary China who struggle with their personal existential crises do not have the social and political power to make changes to their social reality, neither do they have the power to interfere with the decisions of powerholders, where these decisions are influential in causing social changes, changes to Chinese people’s daily life, changes of Chinese natural landscapes and the human-nature relationship in China.


identifier: Peterson, Benjamin James  (2020) Modernizing a Marginal Maritime Metropolis: The Emergence of Canada’s Postwar Planning Practice in Saint John, New Brunswick.  Masters thesis, Concordia University.

abstract: This thesis examines the 1946 Master Plan for the City and County of Saint John, a municipal plan produced between 1944 and its adoption in 1945 by the architect-planner John Campbell Merrett for the City of Saint John, New Brunswick. I examine this document as both a locally and nationally significant development in Canadian architectural and planning histories. Reviewing the many agencies, commissions, and individuals who influenced the development of the 1946 plan, this thesis proposes a broad interpretation of authorship. This thesis seeks two primary outcomes: first, to intervene in a local discourse that misrepresents the legacy of the plan to the detriment of the region’s architectural scholarship. Second, this thesis seeks to engage the 1946 plan in a national discourse that has yet to address the significant contribution of the city of Saint John to Canadian planning in the critical post-Second World War period of Canadian architectural production. This thesis argues that Merrett’s plan both anticipated and mitigated significant economic setbacks and greatly assisted the struggle of the city of Saint John in maintaining its status as a cultural and economic metropolis during the period. The 1946 plan raises foundational questions of Canadian federalism and its influence on the postwar built environment and highlights the continued national influence of Canada’s easternmost regions.


identifier: Wang, Chunrong  (2020) The impact of credit default swaps on corporate capital structure and investment policies.  PhD thesis, Concordia University.

abstract:
Credit default swaps (CDSs) are credit derivatives whose primary purposes include hedging and the trading of credit risks. Unlike other derivatives, such as options or futures, CDSs materially alter lender-borrower relations and thus have real economic effects on the companies referenced by the CDSs. In this thesis, I explore the impact of CDS trading on the cost of capital, corporate capital structure, and corporate social responsibility.

First, I use the universe of U.S. public firms to examine the impact of CDS trading on a firm’s cost of capital during the period 2001 – 2018. My results robustly show that the inception of CDSs causes a significant reduction in a firm’s weighted average cost of capital (WACC). Further analyses reveal that highly levered firms tend to reduce their debt weight, while firms with low leverage increase their usage of debt. Moreover, CDS referenced firms adjust their debt types by using more arm-length debts, while they simultaneously decrease the usage of revolving credits and term loans from banks. The alteration in capital financing choices may be ascribed to the improved information environment and reflects the fact that CDS trading increases debt renegotiation costs but simultaneously also reduces capital supply-side frictions.

After confirming that CDS can impact firms’ financing decisions, I further investigate whether CDS trading can affect a company’s investment in corporate social and environmental activities. A longitudinal sample spanning from 2002 to 2017 across 11 countries and regions was constructed to evaluate the impact. I find that the inception of CDS trading causes a significant reduction in the metric of environmental emission reduction. In addition, the initiation of CDS trading weakly but negatively influences other aspects of CDS firms’ social and environmental performance. Further analysis reveals that investments in emission reduction activities have no relationship to shareholder value creation, whereas engaging in CSR activities related to, e.g., employee, community, or eco-product innovation, etc., increases shareholder wealth. Collectively, my findings reveal one of the downsides of CDSs arising from CDS-protected lenders who become less accommodating over post-CDS periods.


identifier: Benozzo, Marta  (2020) Density of integral points on varieties: Mordell orbifold conjecture and special varieties.  Masters thesis, Concordia University.

abstract: The objective of this thesis is to understand F.Campana’s conjectures about density of integral points on varieties defined over a number field. In the case of curves this is solved by Siegel and Faltings’ theorems: the degree of the canonical divisor of a curve determines whether it has finitely or infinitely many rational points (possibly after a finite extension of the base field). In higher dimension, varieties can be neither potentially dense (the set of rational points becomes dense after at most a finite extension of the base field), nor mordellic (rational points are always finitely many in an open dense subset). The conjectures studied in the thesis address the problems of characterizing potential density and mordellicity of a variety and of constructing a (unique) fibration which splits each variety in its mordellic part, the base of the fibration, and potentially dense part, the fibers. To deal with this problem, F.Campana introduces the notion of orbifold pair: to each variety, one can attach an orbifold divisor, which allows keeping track of multiple fibers of fibrations. Using this tool, he was able to construct a fibration, the core map, which has (orbifold) special general fiber, conjectured to be the potentially dense varieties, and base of (orbifold) general type, conjectured to be the mordellic ones.


identifier: Yu, Ting  (2020) Lean Transformation Frameworks for Hospital Departments.  PhD thesis, Concordia University.

abstract:
Critical issues in hospitals include prolonged wait times and soaring expenditures. While Lean methods appear to be a solution to these issues, Lean implementations are difficult to replicate in different healthcare settings because of a lack of well-established methodologies. Therefore, this thesis applies a unified Lean approach to create transformation frameworks for three major types of hospital departments that are facing different challenges attributed to their underlying characteristics.
The first part of this thesis discusses a framework for schedule-based and treatment-oriented outpatient departments. The framework identifies the best patient mix, schedule, and staffing levels to reduce wait times and improve the utilisation of critical resources. After implementing the framework, an oncology department can run under a one-day regime while reducing patient visit time by 36.3% and increasing the number of daily chemotherapy treatments by 38.6%. The second part of this thesis describes a framework for shared processes in outpatient departments in which scheduled and unscheduled patients coexist. The framework analyses system capability and devises efficient patient and staff schedules to meet demand with supply in a timely fashion. Implementing the framework in a radiology department results in a 21.4% increase in the number of elective patients and 77.1% and 37.2% decreases in the lead times of emergency patients and elective patients, respectively. The final part of this thesis demonstrates a framework for emergency departments receiving unscheduled patient visits. The framework manages the discharge process and plans staffing and materials to alleviate crowding. The estimated results in a case emergency department are a 50.8% reduction in patient length of stay and 41.5% decrease in occupancy rate of stretchers.
The major theoretical contribution of this thesis is its adaptation of several tools, which are organised into a series of structured activities towards Lean systems for different types of hospital departments. In practice, each framework is a comprehensive and step-by-step guideline for hospital managers to follow in their application of Lean to serve more patients, decrease wait time, and use their resources more efficiently. Furthermore, the frameworks are expected to foster a culture of continuous process improvement and facilitate a hospital-wide Lean transformation.


identifier: Poitras Auger, Catherine  (2020) Toxic City: An Inquiry Into Environmental Health Through Graphic Novel Making.  Masters thesis, Concordia University.

format: text text

abstract: Toxic City is a research-creation project composed of a short graphic novel and a written component that investigates the process of making a personal graphic novel about environmental health and toxicity. Drawn by hand, the self-reflective silent graphic novel uses metaphors and the feature of the gutter to illustrate a story around the connections between health, environment and toxicity. The written component is organized around the contribution of this research to the four modes of research-creation as described by Owen Chapman and Kim Sawchuk. The topic of toxicity is analyzed with a deconstruction of health impacts and legal implications, environmental health justice with a reading of Foucault, fiction and graphic media making, and a short autobiography.


identifier: Gibara, Ryan  (2020) Geometric Inequalities and Bounded Mean Oscillation.  PhD thesis, Concordia University.

abstract:
In this thesis, we study the space of functions of bounded mean oscillation (BMO) on shapes. We prove the boundedness of important nonlinear operators, such as maximal functions and rearrangements, on this space and analyse how the bounds are affected by the underlying geometry of the shapes.

We provide a general definition of BMO on a domain in R^n, where mean oscillation is taken with respect to a basis of shapes, i.e. a collection of open sets covering the domain. We prove many properties inherent to BMO that are valid for any choice of basis; in particular, BMO is shown to be complete. Many shapewise inequalities, which hold for every shape in a given basis, are proven with sharp constants. Moreover, a sharp norm inequality, which holds for the BMO norm that involves taking a supremum over all shapes in a given basis, is obtained for the truncation of a BMO function. When the shapes exhibit some product structure, a product decomposition is obtained for BMO.

We consider the boundedness of maximal functions on BMO on shapes in R^n. We prove that for bases of shapes with an engulfing property, the corresponding maximal function is bounded from BMO to BLO, the collection of functions of bounded lower oscillation. When the basis of shapes does not possess an engulfing property but exhibits a product structure with respect to lower-dimensional shapes coming from bases that do possess an engulfing property, we show that the corresponding maximal function is bounded from BMO to a space we define and call rectangular BLO.

We obtain boundedness and continuity results for rearrangements on BMO. This allows for an improvement of the known bound for the basis of cubes. We show, by example, that the decreasing rearrangement is not continuous on BMO, but that it is both bounded and continuous on VMO, the subspace of functions of vanishing mean oscillation. Boundedness for the symmetric decreasing rearrangement is then established for the basis of balls in R^n.


identifier: Forster, Andrew  (2020) Clairvoyant Practices for the Designed World (The Job of the Artist is to De-Design).  PhD thesis, Concordia University.

abstract:
This thesis uses the term ‘designed world’ to designate an envelope that contains what is usually understood as public space. It asks how certain experimental artistic practices can make apparent, from within, our evolving everyday (our human-centered real). It also asserts that the space between the practical fields of art and of design is one area where the importance of such investigations comes into view. A range of concepts – coping, critical spatial practice, de-design, imagination, strange tools, clairvoyance, complicity, real and virtual spaces, the shaping of time, format, design fiction, counter-factual event, and analogy – are introduced to describe how art practices can unsettle or open the designed world to scrutiny. Artist Vito Acconci’s term ‘de-design’ is used as an initial step in showing the kinds of questions that artworks ask of the designed world. Theodore Schatzki’s use of the word art to designate ‘clairvoyant practices’ (that certain practices make change palpable) and Jane Rendell’s term ‘critical spatial practice’ (embedded interventions in urban space) enlarge the scope of these questions. Bernard Stiegler’s idea of the ‘amateur’ contributes to a critical examination of a contemporary ideology of ‘disruptive innovation.’ Clairvoyant practices are associated with a fundamental formulation of imagination as a condition of politics (via Arendt). This radical idea of imagination is nuanced through art historian David Summer’s spatio-temporal inquiry into form, format, and the virtual, as a critical stance in relation to artefacts.

I examine specific artworks, films, performances, choreographies and designed things as ‘clairvoyant,’ i.e.: able to reflect on the designed world on multiple registers, including a spatio-temporal one. I focuses in detail on two contemporary practices that ‘cope’ in a generative manner with the designed world from a position of complicity: Hito Steyerl (in the space of digital practice) and Theaster Gates (in the space of material practice). With Steyerl,  ‘clairvoyance’ is turned towards contemporary digital representation and its manipulation. With Gates it focuses on urban social actions based in musical improvisation. The thesis concludes with a situated description of my own practice, including the studio components of this thesis – the public installation Paraguayan Sea (with Erín Moure) and the video installation The Machine Stops, set in Le Corbusier’s Capitol Complex, Chandigarh.


identifier: Gonzalez Garcia, Giselle  (2020) Caught between Empires: Pre-Famine Irish Immigrants in Santiago de Cuba, 1665-1847.  Masters thesis, Concordia University.

abstract:
This thesis examines the complex experiences of Irish immigrants in city and province of Santiago de Cuba. For some pre-Famine Irish immigrants, Cuba was an island of opportunities, and these often lay in the burgeoning sugar and coffee industries, industries that were dependant of enslaved labour and the slave-trade. Santiago de Cuba, a small city of almost no relevance to the Spanish American empire, appears as an unlikely destination for Irish migrants, but, although they were only a handful of families, their contribution is significant and under-explored.
The present work examines those Irish families who settled permanently in Santiago from the 17th century until the eve of the Irish Great Famine in 1845. They are composed of two distinctive groups of Irish immigrants. The first one arrived from Spain throughout the 17th and 18th centuries. They developed a sense of symbolic Irish identity, expressed through naming practices, and had a hand in creating the élite cohort into which the immigrants of the second group inserted themselves in the early decades of the 19th century. The first group employed strategies to achieve social mobility and to maintain some degree of ethnic cohesion. They saw in marital alliances as a highly strategic practice that placed them into the local élite and into key colonial institutions in order to assimilate and integrate into their host society. By contrast, the second group was composed of a wider cohort of clearly transnational and trans-imperial adventurers. They sojourned in the United States, towards which market they focused their enterprises by creating trading firms and investing in coffee cultivation. They exploited the interstices of the Spanish and British empires, and of the United States’ “informal one”, to become some of the wealthiest planters and merchants in eastern Cuba. By 1827 these groups had merged into one élite that was politically and socially conservative, and religiously Catholic. They were fiercely pro-slavery and fervent supporters of the maintenance of the Spanish colonial status quo.
The arguments made in this work are sustained in primary sources such as letters, genealogical data, parish records, business letters, and diplomat’s dispatches, among others. These sources were found in archival collections in Cuba, Ireland, the United Kingdom, the United States, and Spain.


identifier: Guo, Jinxiu  (2020) Do Announcements of Dividend Payment Frequency Change Matter?  Masters thesis, Concordia University.

abstract:
Recently, we observe an increasing number of firms declaring monthly dividends. Although dividend policy itself has been in the focus of corporate finance literature, changes in dividend payment frequency are not given much attention. The objective of this paper is to investigate the significance of dividend payment frequency changes. This paper specifically analyzed cash dividends and sought to study the potential effect of dividend payment frequency change announcements on the returns of stocks. Meanwhile, this paper serves as an important way of understanding corporate policy decision. To examine the subject, we implement a standard event study of dividend payment frequency changes to detect the market reactions through measuring the abnormal returns occurred during the announcement period. The study found a rising trend in stock returns during frequency increase announcements and vice versa. It therefore reveals that a change in dividend payment frequency is relevant that are perceived as newsworthy in the market, supporting that signaling effect apply equally well to the dividend frequency changes. Further multivariate analysis reveals that the correlation between event period abnormal returns and frequency change remain significant after controlling for other unconditional firm characteristics.
Key Words: Cash dividends, payment frequency, abnormal returns


identifier: Dubé, Céleste  (2020) Toward a Comprehensive Assessment of Relationships with Teachers and Parents for Youth with Intellectual Disabilities.  Masters thesis, Concordia University.

abstract: Youth with intellectual disabilities (ID) are known to present a higher risk for a variety of psychosocial adjustment difficulties. Furthermore, whereas these youth tend to depend on adult caregivers to a greater extent than their typically developing peers, thus making them more likely to potentially benefit from positive relationships with them. Unfortunately, these relationships are all but neglected in research focusing on youth with ID, due to the difficulty of achieving reliable and valid self-report measures with this population, and the limits of informant report in accurately capturing their own perceptions. The goal of the present study was to develop and validate a comprehensive multi-informant (youth, parents, and teachers) measure of relationship quality with parents and teachers specifically developed for your with ID. To do so, this study relies on a sample of Australian (N=253, 67.20% males) and Canadian (N=142, 49.30% males) adolescents with ID (Mage = 15.82). Our results support the reliability, factor validity, discriminant validity (in relation to sex, ID level, country, and comorbidity), convergent validity (with measures of anxiety, depression, externalizing behaviors, and prosocial behaviors reported by youth, their parents, and their teachers), and test-retest stability of this comprehensive measure of relational warm and conflict. The results further support the idea that youth self-reports provide a distinct perspective on relationship quality relative to parents’ or teachers’ reports, and demonstrate that parents and teachers themselves are unable to differentiate their own perspective on these relationships from that of the target youth. Furthermore, the results also suggest a risk of differential item functioning related to teachers’ report of relational warmth in relation to youth with ID presenting comorbid conditions. This measure is likely to help fill an important gap in the literature on relationship quality for youth with ID, and to allow for a much improved assessment process among this population.


identifier: Valyear, Milan  (2020) The role of dopaminergic projections from the ventral tegmental area to the nucleus accumbens core and shell in responding to a discrete alcohol cue in different contexts.  PhD thesis, Concordia University.

abstract:
Environmental stimuli that predict alcohol are powerful triggers for relapse in humans. These stimuli become established as alcohol cues through Pavlovian conditioning and can be grouped into discrete cues (e.g. smell, sight, taste of alcohol) and contexts (e.g. bar). In the current thesis, a Pavlovian conditioning with context alternation procedure was used to measure the capacity for an alcohol-associated context (alcohol context) to influence responding to a discrete alcohol conditioned stimulus (CS). Responding to a discrete alcohol CS was elevated in an alcohol context compared to an equally familiar neutral context. By incorporating other behavioural procedures, the influence of context over responding to a discrete alcohol CS was shown to be persistent and temporally sensitive.

Pharmacology and chemogenetic approaches revealed that dopamine neurotransmission and the activity of ventral tegmental area (VTA) dopamine neurons was necessary for responding to a discrete alcohol CS in a neutral context. Further, chemogenetic inhibition of the dopaminergic projection from the VTA to the nucleus accumbens (NAc) core reduced CS responding in the alcohol and neutral context. Differently, chemogenetic inhibition of the dopaminergic projection from the VTA to the NAc shell selectively reduced CS responding in the alcohol context, and not in the neutral context. Thus, the dopaminergic VTA-to-NAc core projection was necessary for responding to a discrete alcohol CS whereas the dopaminergic VTA-to-NAc shell projection was necessary for the elevation of this behaviour in an alcohol context.

Targeting of tyrosine hydroxylase (TH) positive VTA dopamine neurons and the use of chemogenetics to manipulate neural activity in a circuit-specific manner were validated using immunocytochemistry and electrophysiology, respectively. Chemogenetic designer receptors were selectively (~95%) expressed in TH positive VTA neurons. Chemogenetic inhibition or excitation of VTA dopamine terminals in the NAc modulated the amplitude of electrically-evoked excitatory postsynaptic currents in NAc core medium spiny neurons (MSNs). Thus, a circuit-specific chemogenetic approach could be used to target VTA dopamine neurons and bidirectionally affect the activity of postsynaptic MSNs.

Based on the finding that the VTA-to-NAc shell projection was necessary for the elevation of CS responding in the alcohol context, the sufficiency of activating VTA dopamine neurons and their projection to the NAc shell to drive CS responding was tested. Chemogenetic activation of VTA dopamine neurons failed to impact responding to a discrete alcohol CS in a neutral context, despite affecting feeding behaviour in the same rats. Further, chemogenetic activation of the dopaminergic VTA-to-NAc shell projection failed to affect CS responding in the alcohol and neutral context. Thus, chemogenetic activation of VTA dopamine neurons or their projections to the NAc shell was not sufficient to elevate responding to a discrete alcohol CS.

The lack of an effect of activating dopaminergic substrates on responding to a discrete alcohol CS suggested that non-dopaminergic circuits are recruited to elevate responding to a discrete alcohol CS in an alcohol context. This hypothesis was examined by microinfusing a glutamate-like agonist in the NAc shell during tests for CS responding in the neutral and alcohol context. Responding to a discrete alcohol CS was selectively reduced by microinfusion of a glutamate-like agonist in the alcohol context and was unaffected in the neutral context. This selective effect on CS responding in the alcohol context implicates glutamatergic activity in the NAc shell in the influence of context over responding to a discrete alcohol CS.

In summary, responding to a discrete alcohol CS is elevated in an alcohol context and the influence of context over this behaviour is persistent and temporally sensitive. Responding to a discrete alcohol CS requires the activity of VTA dopamine neurons and their projections to the NAc core. The elevation of responding to a discrete alcohol CS in an alcohol context requires the dopaminergic projection from the VTA to the NAc shell. Attempts to elevate responding to a discrete alcohol CS by activating dopaminergic or glutamatergic substrates either failed to affect or reduced CS responding, respectively. Thus, the circuits sufficient to elevate responding to a discrete alcohol CS may involve the coordinated activation of dopaminergic and glutamatergic inputs to the NAc shell. Ultimately, a detailed description of the circuits that mediate the influence of discrete cues and contexts over responding for alcohol will inform the development of efficacious behavioural and pharmacological therapies for alcohol use disorder.


identifier: Sun, Yanming ORCID: https://orcid.org/0000-0003-0471-8215 <https://orcid.org/0000-0003-0471-8215>  (2020) A Computation-Efficient CNN System for High-Quality Brain Tumor Segmentation.  Masters thesis, Concordia University.

format: text video

abstract:
Brain tumor diagnosis is an important issue in health care. Automated brain tumor segmentation can help timely diagnosis. It is, however, very challenging to achieve high-quality segmentation results, because the shapes, sizes, textures and locations of brain tumors vary from patient to patient. To develop a Convolutional Neural Network (CNN) system for a high-quality brain tumor segmentation at the lowest computation cost, the CNN should be custom-designed to extract efficiently sufficient critical features particularly related to the tumors from brain images for the multi-class segmentation of tumor areas.
    In this thesis, a CNN system is proposed for brain tumor segmentation. The system consists of three parts, a pre-processing block to reduce the data volume, an application-specific CNN (ASCNN) to segment tumor areas precisely, and a refinement block to detect false positive voxels. The CNN, designed specifically for the task, has 7 convolution layers, and the number of output channels per layer is no more than 16. The convolutions combined with max-pooling in the first half of the CNN are performed to localize brain tumor areas. Two convolution modes, namely depthwise convolution and standard convolution, are performed in parallel in the first 2 layers to extract elementary features efficiently. In the second half of the CNN, the convolutions combined with upsampling are to segment different tumor areas. For a fine classification of pixel-wise precision, the feature maps are modulated by adding the weighted local feature maps generated in the first half of the CNN. The system has only 11716 parameters to be trained and, for a patient case of (240x240x155 x3) voxels, it requires only 21.14G Flops to complete the test. Hence, it is likely the simplest CNN system, so far reported, for brain tumor segmentation.
    The performance of the proposed system has been evaluated by means of CBICA Image Processing Portal with samples from dataset BRATS2018. Requiring a very low computation volume, the proposed system delivers a high segmentation quality indicated by its average Dice scores of 0.75, 0.88 and 0.76 for enhancing tumor, whole tumor and tumor core, respectively, and the median Dice scores of 0.85, 0.92, and 0.86. Its processing quality is comparable to the best ones so far reported. The consistency in system performance has also been measured, and the results have demonstrated that the system is able to reproduce almost the same output to the same input after retraining.
    In conclusion, the proposed CNN system has been designed to meet the specific needs to segment brain tumors or other kinds of tumors in medical images. In this way, the redundancy in computation can be minimized, the information density in data flow increased, and the computation efficiency/quality improved. This design demonstrates that a CNN system can be made to perform a high-quality processing, at a very low computation cost, for a specific application. Hence, ASCNN is an effective approach to lower the barrier of computation resource requirement of CNN systems in order to make them more implementable and applicable for general public.


identifier: Lagota, Kelvin  (2019) Green function and self-adjoint Laplacians on polyhedral surfaces.  PhD thesis, Concordia University.

abstract: Using Roelcke's formula for the Green function, we explicitly construct a basis in the kernel of the adjoint Laplacian on a compact polyhedral surface X and compute the S-matrix of X at the zero value of the spectral parameter. We apply these results to study various self-adjoint extensions of a symmetric Laplacian on a compact polyhedral surface of genus two with a single conical point. It turns out that the behaviour of the S-matrix at the zero value of the spectral parameter is sensitive to the geometry of the polyhedron.


identifier: Chen, Zhikun  (2020) Green Surface-washing Agent and Oily Waste Management for Oil Spill Response.  Masters thesis, Concordia University.

abstract:
Oil spills in the marine environment frequently reach the coastal zone where active cleanup strategies may become necessary if the rates of natural weathering and attenuation of the stranded oil are considered inadequate. The application of surface-washing agents (SWAs) is an operational technique that enhances the separation and removal of oil that is adhered to solid surfaces. This study presents a comprehensive review of the current and emerging technologies to treat oiled shorelines using SWAs. The literature review includes a brief description of the characteristics of shoreline oiling and the current available techniques for shoreline treatment or cleanup. It summarizes the basics of surface washing and state-of-the-art efforts to date on oil removal using SWAs at both laboratory and field scales. The development trends of green SWAs for shoreline treatment are further introduced.

To develop the novel green SWA, the use of nanocellulose-based nanofluid as a SWA was studied by investigating its reactivity and effectiveness. Salinity was found to be the most influencial factor to facilitate oil removal with the nanofluids. Cations from salt can promote the adsorption of nanocellulose on the oil/water interface by reducing the surface charges. The experimental results revealed the nanocellulose could be effective at low concentrations but an excess of nanocellulose hindered oil removal due to an increase in fluid viscosity. The biotoxicity tests showed that nanocellulose-based nanofluid did not have negative effects on algae growth and introducing nanocellulose into an oiled culture medium can actually mitigate the toxicity of the oil on algae. A comparison in removal efficiency with other surfactants demonstrated the potential value for shoreline cleanup due to the superior effectiveness of nanocellulose-based nanofluids. It was found that the nanocellulose has a high potential for application as a surface-washing agent for shoreline cleanup due to the low cost, low toxicity, and high efficiency.

In addition, the shoreline cleanup operation can generate large amount of oily waste which requires further treatment. It is necessary to develop a programming model for oily waste management. An inexact chance-constrained programming model (ICCP) was developed with the consideration of uncertain environments, which cannot only consider the probability distribution of random variable but also interval parameters. The developed model was applied to a hypothetical oily waste management system. The interval solutions obtained from ICCP model included facilities selection, waste flow allocations, and expected time length under different constraint-violation risks. It is an effective tool to minimize the system cost of oily waste management with uncertainties. The obtained solutions could support the managers for the trade-off between system cost and risk level.


identifier: Patel, Smita  (2020) The Effects of Ovarian Hormones on Memory Bias and Progesterone Receptors in Female Rats.  Masters thesis, Concordia University.

abstract: Ovarian hormones can bias female rats to use one memory system over another when navigating a novel or familiar environment, resulting in a memory bias. High levels of estrogen (E) promotes places memory while low level of E promotes response memory. However, little is known about the effects of progesterone (P) on memory bias. Experiment 1 determined whether P affects memory bias. Ovariectomized (OVX) female rats were trained in a plus shaped maze, which assesses memory system bias, and received one of three hormonal treatments: Low 17β estradiol (E2), high E2 or high E2 + P. P did affect memory bias by reversing the effects of high E2 when rats receive P one hour prior to testing. To understand the mechanisms by which P affect memory bias in the hippocampus (HPC), antibodies directed at nPR, mPRβ and mPRδ were examined. The effects of low E2, high E2, and high E2+P were examined on immunoreactivity to these receptors in the HPC. All three receptor-types were found in the female rat HPC and were found to be insensitive to hormone administration. The presence of these receptors suggests that P can exert both genomic and non-genomic effects in the HPC. Other brain areas involved in memory bias remain to be examined further.


identifier: Schofield, Dona Leigh  (2020) Racialization, Agency, and the Law: Wendake First Nation Confronts the Canadian Criminal Justice System, 1918-1939.  Masters thesis, Concordia University.

abstract: Throughout the nineteenth century, the Province of Canada enacted a series of laws in an effort to extend their jurisdiction over the lands and peoples residing in the territory. Even though, in theory, these laws applied equally to everyone, for Indigenous peoples, the impact of state expansion occurred alongside the Canadian government’s assimilationist policies. Conceptualized as an “Indian Problem”, the 1876 Indian Act sought to regulate Indigenous people by labelling them as a separate racial category; thereby creating two types of legal persons: “Indian” and “non-Indian”. Given that this racial distinction was deeply embedded into the colonial structure, it shaped Indigenous people’s interactions with state institutions, including the justice system. This thesis examines the implementation of Canadian criminal law vis-à-vis members of the Wendake First Nation and the different ways in which they navigated the legal system between 1918 and 1939. Drawing from a total of 34 court cases, I argue that the law operated as a tool of colonial control to uphold racial distinctions between Indigenous and non-Indigenous people. At the same time, this study also reinforces the notion that the Wendat were active historical agents who played a role in negotiating and renegotiating their role in the new colonial order. Although these two themes – racialization and agency – seem to contradict each other, this thesis demonstrates that not only can they be reconciled, but twentieth-century court cases provide important historical insights into the origins of today’s Indigenous overrepresentation in the criminal justice system.


identifier: Maedeh, Mehranfar  (2020) Financial Risk Management in Electricity Markets.  Masters thesis, Concordia University.

abstract: This research studies a decision problem to allocate an electricity trading firm’s budget to its trading strategies using a risk management framework. The considered problem consists of maximizing a firm’s profit while controlling two risk measures: the variance of the portfolio and the conditional value at risk. The dependence structure of the returns associated with different trading strategies is modelled using vine copulas and it is assumed that the marginal distribution of the returns originates from the Johnson family of distributions. The studied problem is formulated as a stochastic integer quadratic program and solved it with a commercial optimization software. The proposed mathematical program is assessed on the firm’s portfolio and the obtained results are discussed.


identifier: Fardnia, Pedram ORCID: https://orcid.org/0000-0002-6425-4857 <https://orcid.org/0000-0002-6425-4857>  (2020) Essays in Corporate Governance.  PhD thesis, Concordia University.

title: Essays in Corporate Governance

abstract:
Corporate governance is a heavily researched area in the finance literature, with previous studies exploring a multitude of variables that describe a firm’s board structure, management, compensation, etc., and how they affect corporate decisions, firm performance, and various other aspects of corporate life. Corporate governance has important implications for nearly all business entities, yet many research questions within the field still remain unaddressed.
In the first part of my thesis, I explore the relation between corporate governance practices and shareholder litigation. At the same time, I explore whether firms improve any shortcomings in their governance structure and/or governance practices post-litigation. We find evidence that variables that describe a firm’s corporate governance, the compensation of its CEO, as well as the CEO’s characteristics have a significant influence on the firm’s litigation risk. Our results further show that, after a lawsuit, sued firms tend to improve their corporate governance and the proportion of their independent directors. In summary, our results provide important insights into the role of ex-ante active monitoring (via the board of directors) versus ex-post passive monitoring (via shareholder litigation), and how litigation as a passive monitoring device can cause firms to improve their active monitoring.
In another research, I choose the aviation industry and examine the potential effects corporate governance policies may have on the safety record of that industry. Pilot errors and mechanical failures, which are responsible for 75% of all accidents, are, to some extent, preventable because they relate to the way an airline company is managed. My findings reveal that airline safety is significantly affected by a series of firm-level characteristics that describe an airline’s governance as well as its financial well-being. In addition, I find that airline safety is affected by a variety of country-level factors that characterize the legal, institutional, and economic environment of a given country, as well as its air transport infrastructure. The results of this study have important policy implications for both the airline industry and regulators. To allocate resources more efficiently, regulators may find it beneficial to focus their supervision on airlines with poor governance practices as well as airlines that are in financial distress.


identifier: Masadeh, Mahmoud Saleh ORCID: https://orcid.org/0000-0001-7447-1276 <https://orcid.org/0000-0001-7447-1276>  (2020) Adaptive Approximate Computing for Enhanced Quality Assurance.  PhD thesis, Concordia University.

abstract:
Approximate Computing (AC) has been widely advocated for energy-efficiency in error-tolerant applications as it offers the opportunity to trade-off output quality for reduced power consumption and execution time. Approximate accelerators, which consist of a large number of functional units, have been proposed in error-resilient applications, to speed-up regularly executed code elements while assuring defined quality constraints. However, with an approximate static design, while the average output quality constraint is satisfied, the quality of individual outputs varies significantly with dynamically changing inputs. Thus, quality assurance is an essential and non-trivial problem. State-of-the-art approaches in approximate computing address this problem by precisely re-evaluating those quality-violating accelerator invocations. However, such methods can significantly diminish or even cancel the benefits of approximation, especially when the rate of input data variations is high and approximate errors are considerably above a user given threshold, i.e., target output quality (TOQ).
As a general solution to this problem, in this thesis, we propose a novel methodology to enhance the quality of approximation by two approaches: 1) design adaptation by predicting the most suitable settings of the approximate design to execute the inputs; and/or 2) error compensation by predicting the error magnitude to use in adjusting the output results. The proposed method predicts the design settings, or the error magnitude based on the applied input data and user preferences, without losing the gains of approximations. We mostly consider the case of approximate accelerators built with approximate functional units such as approximate multipliers, where we design a library of approximate accelerators with 20 different settings of 8 and 16-bit approximate multipliers.

For the adaptive approximate computing, we use machine learning (ML) algorithms to build an efficient and lightweight design selector to adapt the approximate accelerators to meet a user-defined quality constraint. Compared with contemporary techniques, our approach is a fine-grained input-dependent approximation approach, with no missed approximation opportunities or rollback recovery overhead. The proposed method applies to any approximate accelerator with error-tolerant components, and it is flexible in adapting various error metrics. We fully automate the proposed methodology of quality assurance of approximate accelerators using ML-based models, for both software and hardware implementations. The obtained analysis results of image processing and audio applications showed that it is possible to satisfy the TOQ with an accuracy ranging from 80% to 85.7%. The hardware implementation is based on Field Programmable Gate Arrays (FPGA) approximate adaptive accelerator with constraints on size, cost, and power consumption, which rely on dynamic partial reconfiguration to assist in satisfying these requirements.

To ensure the quality of results for a single approximate design rather than a library, we build a decision tree-based model for error compensation. The proposed model detects the magnitude of approximation error based on design inputs. Then, it enhances the accuracy of the approximate result by adding the error magnitude to it. The proposed methodology is able to enhance the quality of image processing applications with a negligible overhead.


identifier: Bai, Zhuola  (2020) Are Close-by Investors Better Monitors? An Examination of the Link between Investor Proximity and Corporate Governance.  Masters thesis, Concordia University.

abstract: In this thesis, we study whether the geographic proximity between institutional investors and firms affects the corporate governance characteristics of firms. Using indices that capture both a firm’s external and internal governance quality as well as five individual governance mechanisms, we show that – compared to nonlocal institutional investors – the presence of local investors weakens a firm’s internal governance but improves its external governance. The findings of this study offer important insights pertaining to the debate how investor proximity affects corporate governance quality. Specifically, they provide supporting evidence for the substitution theory that argues that internal and external governance are interchangeable – in this case with close-by investors making up for poorer internal governance. Finally, we investigate firms’ preference for corporate governance mechanisms based on both their ex-ante firm characteristics and the presence of local investors. Our results suggest that smaller, less liquid firms have weaker boards and fewer antitakeover provisions if they are located in close proximity to their largest institutional investors.


identifier: Jamil, Mahrukh  (2020) The Longitudinal Associations Between Endothelial Function and Diabetes Type II and Diabetes Related Outcomes in People with No Major Non-Communicable Chronic Diseases: A Systematic Review.  Masters thesis, Concordia University.

abstract: Context: Endothelial function plays a very important role in controlling vascular tone, inflammatory responses, immune responses and haemostasis. It has been linked with the progression of diabetes type II in the literature, but it is still not known whether diabetes is a cause or consequence of endothelial dysfunction. Also, there are no systematic reviews available on this topic. Objective: To explore whether endothelial function is associated with type II diabetes and other diabetes related outcomes in apparently healthy participants with no non-communicable diseases using a systematic review. Data sources: PubMed, Scopus and Web of Science databases were searched, from inception to September 2019, for articles published in English and French. Search terms include synonyms of diabetes type II, HbA1c, endothelial function, flow-mediated dilation and finger plethysmography. Study selection: Longitudinal studies and cohort/placebo/control group of interventions studies with non-invasive endothelial function measures—flow mediated dilation (FMD) and reactive hyperemia index (RHI)—at the start of the study and a diagnosis of type II diabetes or any surrogate measure of diabetes at follow-up were included. Data Extraction: Data extraction and quality assessment using Newcastle-Ottawa scale for cohort studies were performed by the two reviewers independently. Data synthesis: Qualitative data synthesis was performed. Result: The search yielded 20141 retrieves, 12429 articles were obtained after deduplication, out of which 127 were screened for full text, 16 selected articles were used for data extraction and author’s contact. Four articles were included for final analysis. Three studies reported a non-significant relationship between endothelial function and fasting plasma glucose and HbA1c; whereas one study reported significant results for endothelial function and incidence of diabetes. Conclusion: The available evidence from this review did not show any statistically significant association between endothelial function (measured by FMD and RHI) at baseline and surrogate measures of diabetes type II (fasting blood glucose, HbA1c) but showed limited evidence(with only one article) that endothelial function at baseline is associated with the diagnosis of type II diabetes. More longitudinal studies with healthy participants having primary focus on the association are required to provide more evidence in this domain.


identifier: Dakik, Pamela  (2020) Prolonging the Longevity of Budding Yeast: New Aging-Delaying Plant Extracts and the Identification of their Cellular Signaling Pathways.  PhD thesis, Concordia University.

abstract:
In studies presented in this thesis, we used a robust cell viability assay to conduct two screens of commercially available plant extract libraries in search of plant extracts that can delay chronological aging and prolong the longevity of the budding yeast S. cerevisiae. Many of the plant extracts in the library have been used for centuries in traditional Chinese and other herbal medicines or the Mediterranean and other customary diets. None of these plant extracts, however, were previously tested for their ability to slow aging and extend the longevity of any organism. Our screens have allowed us to discover twenty-one plant extracts that significantly prolong the longevity of chronologically aging yeast cells that are not limited in calorie supply. We provided evidence that each of these longevity-extending plant extracts is a geroprotector that lowers the rate of yeast chronological aging and elicits a hormetic stress response. Our findings demonstrated that the efficiencies of aging delay and longevity extension by many of these geroprotective plant extracts significantly exceed those for any of the chemical compounds previously known for their abilities to slow aging and prolong lifespan in yeasts, filamentous fungi, nematodes, fruit flies, daphnias, mosquitoes, honey bees, fish, mammals and cultured human cells. Our findings also revealed that each of the twenty-one geroprotective plant extracts mimics in limited in calorie supply yeast cells v
that are not the aging-delaying, longevity-extending, stress-protecting, metabolic and physiological effects of a caloric restriction diet. We also demonstrated that the discovered geroprotective plant extracts elicit partially overlapping effects on a distinct set of longevity-defining cellular processes. Such processes include the coupled mitochondrial respiration, maintenance of the electrochemical potential across the inner mitochondrial membrane, preservation of the cellular homeostasis of reactive oxygen species, protection of cellular macromolecules from reactive oxygen species- inflicted oxidative damage, maintenance of cell resistance to oxidative and thermal stresses, the efficiency of the lipolytic cleavage of neutral lipids deposited and stored in lipid droplets. We provided evidence that some of the discovered geroprotective plant extracts slow yeast chronological aging because they target different hubs, nodes and/or links of the longevity-defining network integrating specific evolutionarily conserved signaling pathways and protein kinases.


identifier: Gill, Donal S.  (2020) The Politics of Travel in Gulliver’s Travels.  PhD thesis, Concordia University.

abstract: When, in Book II, Chapter VII, the King of Brobdingnag says to Gulliver “As for yourself […] who have spent the greatest part of your life travelling; I am well disposed to hope you may hitherto have escaped many vices of your country” (Book II, Ch. VII: 121), he raises an important question—that of the value of travel as a means to correct the individual. The primary original contribution of this dissertation is to take Gulliver’s Travels by Jonathan Swift (1726) seriously as a work of political theory, specifically on the question of the value of travel as a means of individual edification. This dissertation extracts from the text a political argument concerning the pitfalls of the assumption that travel is of benefit to individuals in all circumstances. In doing so, it places Swift in dialogue with Locke, Shaftesbury, the proponents of the Baconian scientific project, and Montaigne, as well as extracting an overarching criticism of liberal and enlightenment values through the critique of travel. Through a close reading of Gulliver’s Travels, alongside key political and religious contextual analysis, the dissertation assesses the text’s treatment of the relationship between travel, education, science, and politics. This dissertation extracts from Swift’s text an argument that travel can only be edifying if pursued in a disciplined manner as part of an organic hierarchical society, opening up a wider criticism of Modernist and Enlightenment ideas of education.


identifier: Haghi, Maryam  (2020) Integrated Scheduling Problems in Healthcare and Logistics.  PhD thesis, Concordia University.

abstract:
Scheduling is one of the important components of operation management in different services. The goal of scheduling is to allocate limited available resources over time for performing a set of activities such that one or more objectives are optimized. In this thesis, we study several interesting applications of scheduling in health care and logistics. We present several formulations and algorithms to efficiently solve the scheduling problems that arise in these areas.

We first study static and dynamic variants of a multi-appointment, multi-stage outpatient scheduling problem that arises in oncology clinics offering chemotherapy treatments. We present two integer programming formulations that integrate numerous scheduling decisions, features, and objectives of a major outpatient cancer treatment clinic in Canada. We also develop integrated and sequential scheduling strategies for the dynamic case in which arriving requests are processed at specific points of time.
The results of computational experiments show that the proposed scheduling strategies can achieve significant improvements with respect to the several performance measures compared to the current scheduling procedure used at the clinic.

We next present a daily outpatient appointment scheduling problem that simultaneously determines the start times of consultation and chemotherapy treatment appointments for different types of patients in an oncology clinic under uncertain treatment times. We formulate this stochastic problem using two two-stage stochastic programming models. We also propose a sample average approximation algorithm to obtain high quality feasible solutions. We use an efficient specialized algorithm that quickly evaluates any given first-stage solution for a large number of scenarios. We perform several computational experiments to compare the performance of proposed two-stage stochastic programming models. In the next part of the experiments, we show that the quality of the first-stage solutions obtained by the sample average approximation is significantly higher than those of the expected value problem, and the value of stochastic solution is extremely high specially for higher degrees of uncertainty.

Finally, we address two variants of a cross-dock scheduling problem with handling times that simultaneously determines dock-door assignments and the scheduling of the trucks. In the general variant of the problem we assume that unit-load transfer times are door dependent, whereas in the specific case variant, unit-load transfer times are considered to be identical for all pairs of doors. We present constraint programming formulations for both variants of the problem, and we compare the performance of these models with mixed integer programming models from the literature. For the specific case, we propose several families of valid inequalities that are then used within a branch-and-cut framework to improve the performance of a time-index model. To solve the general problem efficiently, we also develop an approximate algorithm that first solves the specific case problem with the developed branch-and-cut algorithm to obtain a valid lower-bound, and then applies a matheuristic to obtain a valid upper-bound for the general problem and to compute the optimality gap. According to the computational experiments, we show that the proposed formulations and algorithms are able to solve the studied problems efficiently, and they outperform other models and heuristics that were previously developed for the problem in the literature.


identifier: Teixeira, Vinicius  (2020) Citizen Sousveillance: The Use of Sousveillance in Protests. The Case of Mídia NINJA.  Masters thesis, Concordia University.

abstract:
The power dynamics of the gaze have been examined from different perspectives, from the use of surveillance for safety purposes and the monitoring of citizens, to concepts that study how alternative gazes impact in society and its actors.  One of these alternative gazes has been described as sousveillance (Mann, 1998). While surveillance refers to watching from above, sousveillance is its direct opposite, watching from below. Based on this dynamic, and using a Brazilian group of activists that practices sousveillance as a case study, this thesis proposes a new term called Citizen Sousveillance. This term highlights the particular, protective role that sousveillance can play in protest contexts, preventing police brutality and other forms of injustice, as well as its capacity to change the reality of protest as a whole.
Citizen Sousveillance encompasses five dimensions: 1. a nonviolence dimension—it can act as a nonviolent form of resistance and as protection against violent repression; 2. a raw reality dimension—it can work to spread, if not an unmediated version of reality, a more raw reality of protest than we would see in coverage produced by corporate mainstream media; 3. a counternarrative dimension—it provides material that can be used to create narratives that act as counterpoints to corporate, mainstream media coverage of protest; 4. an archival dimension—it can help accumulate media that records and preserves records of protest for historical purposes; and 5. a virtual dimension—it can work as a channel for those not involved in protests to still follow its developments. These dimensions — and the concept of Citizen Sousveillance itself —were discerned through an empirically-grounded analysis of the activities of a Brazilian activist group called Mídia NINJA. The social media work of this group, as well as interviews with five members, make up the case-study around which this thesis is organized.


identifier: Cheney, William  (2020) Development of a Yeast-Based Opioid Biosensor by Adaptation of Pheromone Response Pathway.  Masters thesis, Concordia University.

abstract: Opioids are simultaneously an essential medicine and a leading cause of death. Metabolic engineering and novel opioids offer solutions to insecure supply chains and harmful side effects but are limited by cost and time required for high throughput screening. We have developed a yeast-based opioid biosensor to accelerate opioid research. Utilizing Homo sapiens µ-opioid receptor as a detector, our biosensor provides a simulacrum of in vivo opioid response while maintaining ease of implementation of a yeast chassis. Functional µ-opioid receptor expression required the introduction of cholesterol biosynthesis as well as pH adjustment. We also identified codon usage as a parameter affecting Homo sapiens melatonin receptor1a function and the properties of the µ-opioid receptor binding. Under optimized conditions our opioid biosensor displayed 157-fold increase in fluorescence after opioid exposure and had µM affinity for opioid peptides and mM affinity for morphine. This opioid biosensor can aid high throughput screening and provides clues for future functional expression of other difficult G-protein coupled receptors.


identifier: Matte, Jean-Michel  (2020) Density dependence in animal populations: effects of biological predictors and methodological biases.  PhD thesis, Concordia University.

abstract: The importance of density in the regulation of animal populations is well established, but the mechanisms by which it operates are still equivocal. More specifically, the extent to which density influences individual fitness remains uncertain, and the variability in responses to density across gradients of environmental conditions, and between distinct populations, species, taxonomic classes, and experimental designs has received limited empirical investigation. Using a combination of field experiments with salmonids and meta-analyses at a broader scale, my thesis investigates the relationship between density, somatic growth, and survival, and the extent by which these relationships can be related to biological predictors and methodological biases. In chapter 1, the mechanisms of density dependence are investigated by manipulating the density (range: 0.3 - 7 fish/m^2) of young-of-the-year brook trout (Salvelinus fontinalis) in three genetically distinct populations (θST = 0.13-0.30) during three consecutive summers in sections of streams in Cape Race, Newfoundland. I found that populations exhibited population-specific patterns of density dependence that were consistent across years, which were partially related to environmental conditions. In chapter 2, the mechanisms of competition that cause density dependence in these populations were investigated. To do so, I quantified the consumption and depletion of invertebrate prey communities across brook trout densities in the same experiment as chapter 1. My results demonstrated that strong density dependence can occur without prey depletion or reductions in consumption, suggesting that alternative mechanisms can be important. In chapter 3, a meta-analysis was conducted to quantify the relative importance of biological predictors and methodological biases on the patterns of density dependence in salmonids. This meta-analysis demonstrated that methodological biases (experimental design, density gradient) were better predictors of the shape and strength of density dependence across salmonids than biological predictors (food abundance, predators, habitat, species). However, salmonids differ from other animals in several key ways (e.g. territoriality, life history, habitat, etc.), and whether relationships derived from salmonids can be applied to other animals is uncertain. Therefore, in chapter 4, I conducted a similar meta-analysis at a broader scale across all animals, to quantify the prevalence of the same biological predictors and methodological biases on density dependence, and to quantify potential differences across taxonomic classes. Patterns of density dependence across animals varied according to both biological (taxonomic groups, food abundance, age) and methodological biases (density gradient). However, these relationships were different than those present in salmonids, suggesting that important variation occurs at multiple taxonomic levels. Overall, my thesis demonstrates that the patterns of density dependence can vary according to multiple factors simultaneously (environment, populations, taxonomic classes, methodology). These findings have important implications for the management of wild populations and our understanding of density dependence. More specifically, they demonstrate that the outcome of density dependence is highly context-dependent, and that care should be exercised both for research and the management of endangered populations.


identifier: Broley, Laura  (2020) The Development of (Non-)Mathematical Practices through Paths of Activities and Students’ Positioning: The Case of Real Analysis.  PhD thesis, Concordia University.

abstract: Previous research has found that within elementary university courses in single variable and multivariable Calculus, the activities proposed to students may enable and encourage the development of non-mathematical practices. More specifically, the research has shown that students can obtain good passing grades by learning highly routinized techniques for a restricted set of task types, with little to no understanding of the mathematical theories that justify the choice and validity of the techniques. We were interested in knowing what happens as students progress to more advanced courses in Analysis. The study presented in this thesis focussed on a first Real Analysis course at a large urban North American university. To frame our study, we turned to the Anthropological Theory of the Didactic, which offers theoretical tools for modelling practices as they exist within and across institutions. We analyzed various course materials to develop models of practices students may have been expected to learn in the course. These were then used to inform our construction of a task-based interview that would allow us to elicit and model practices students had actually learned. Interviews were conducted with fifteen students shortly after they passed the course. In our qualitative analyses of the resulting data, we found that students’ practices were (non-)mathematical in different ways and to varying degrees. Moreover, this seemed to be linked not only to the kinds of activities students had been offered in the course, but also to the characteristically different ways in which students may have interacted with those activities. As theoretical tools for thinking about these links, we introduce the notion of a path to a practice and a framework of five positions that students may adopt in a university mathematics course institution: the Student, the Skeptic, the Mathematician in Training, the Enthusiast, and the Learner. We discuss the possibility of designing paths of activities that might perturb students’ positioning and encourage the development of practices that are more mathematical in nature.


identifier: Valognes, Julien  (2020) Methods to Robust Ranking of Object Trackers and to Tracker Drift Correction.  Masters thesis, Concordia University.

abstract:
This thesis explores two topics in video object tracking: (1) performance evaluation of tracking techniques, and (2) tracker drift detection and correction. Tracking performance evaluation consists into comparing a set of trackers' performance measures and ranking these trackers based on those measures. This is often done by computing performance averages over a video sequence and then over the entire test video dataset, consequently resulting in an important loss of statistical information of performance between frames of a video sequence and between the video sequences themselves. This work proposes two methods to evaluate trackers with respect to each other. The first method applies the median absolute deviation (MAD) to effectively analyze the similarities between trackers and iteratively ranks them into groups of similar performances. The second method gains inspiration from the use of robust error norms in anisotropic diffusion for image denoising to perform grouping and ranking of trackers. A total of 20 trackers are scored and ranked across four different benchmarks, and experimental results show that using our scoring evaluation is more robust than using the average over averages.
In the second topic, we explore methods to the detection and correction of tracker drift. Drift detection refers to methods that detect if a tracker is about to drift or has drifted away while following a target object. Drift detection triggers a drift correction mechanism which updates the tracker's rectangular output bounding box. Most drift detection and correction algorithms are called while the target model is updating and are, thus, tracker-dependent. This work proposes a tracker-independent drift detection and correction method. For drift detection, we use a combination of saliency and objectness features to evaluate the likelihood an object exists inside a tracker's output. Once drift is detected, we run a region proposal network to reinitialize the bounding box output around the target object. Our implementation applied on two state-of-the-art trackers show that our method improves overall tracker performance measures when tested on three benchmarks.


identifier: Pham, Nhat  (2020) Importin-binding Regulates Contractile Proteins for Cytokinesis.  Masters thesis, Concordia University.

abstract: Cytokinesis, the last step of mitosis, describes the physical separation of a cell into two daughters. In metazoan cells, a contractile ring composed of actin and myosin forms at the division plane and constricts the plasma membrane of the cell. Failure to complete cytokinesis or aberrant cell division can result in changes in fate or cause aneuploidy, both of which are hallmarks of cancer and other pathologies. To ensure that the assembly and constriction of the contractile ring is spatiotemporally coordinated with chromosome segregation, multiple pathways function cooperatively to regulate the localization and function of contractile proteins. These include pathways from the mitotic spindle, which provides cues for ring assembly and positioning. In addition, our lab recently uncovered a novel pathway which senses chromatin to position the ring. The work described here helped to elucidate the molecular mechanisms by which spindle-dependent and -independent pathways work together for cytokinesis, and to find novel targets of the chromatin pathway. Here, we show how the binding of importins, microtubules and RhoA are coordinated to regulate the scaffold protein anillin for cytokinesis. We also show that the NLS of Ect2, the activator of RhoA, is required for cytokinesis. Finally, to identify other contractile proteins regulated the Ran pathway in cytokinesis, a BioID of importin-β1 identified 206 potential new mitotic proximity interactors.


identifier: Deng, Lu  (2020) The Time Relationship between Stock option and Repurchase.  Masters thesis, Concordia University.

abstract: This paper examines the time relationship between repurchases and stock option exercises in the firms. Firms with more option exercised in the last year and current year are more likely to make repurchase decision. On the one hand, repurchase can help alleviate dilution caused by past option exercises. On the other hand, managers match the expenses on repurchases with the payment of contemporaneous option exercises to realize the stable cash flow. Total options outstanding also affect the likelihood of repurchase decision, which means managers may consider expected future option exercises in decision-making. Once the decision is made, past, concurrent option exercises and expected future stock option exercises are also positively related to actual repurchase level (dollars spent on repurchase). Contemporaneous relation is the strongest in both regressions as previous paper suggests. We also find that executive options outstanding have a positive effect on the likelihood of repurchase decision and actual repurchase level. This paper also uses propensity score matching method to test the effects of repurchase activity and high option holdings (which ranks the 1st quartile with the same industry) on firms’ profitability indicator ROA. We find that a high percentage of executive options, instead of a high holding of total stock options, has a positive effect on ROA in repurchasing firms.


identifier: Valentine Freeman, Jeremy  (2020) Un-Decadence: Counter-Poetries and Decadent Aesthetics in the British Fin-De-Siècle.  PhD thesis, Concordia University.

abstract: This dissertation examines and categorically reforms the accepted construction of fin-de-siècle decadence. In this study I grapple with how we understand the nature of fin-de-siècle cultural history and how theories of decadence during the late-nineteenth century may be usefully complicated by an analysis of fin-de-siècle decadence as a non-unitary discursive program. Cumulatively this study reimagines Victorian, fin-de-siècle and modernist literatures in relation to decadent aesthetics read through a sustained investigation of discourse and generic forms in the period. To this end I examine three late-Victorian poets’ methods of construction and models of poetic and aesthetic form as they wrote, shaped and published their works in order to demonstrate how they incite us to alter and re-define our conception of decadence as a historical category. For this critical intervention I have chosen a set of authors—Edward Carpenter, John Davidson and Sarojini Naidu—whose work exemplifies three poetic models that, I argue, actively engaged with and reformed the tropes, arguments and methods of fin-de-siècle decadence. Edward Carpenter’s poetry is emblematic of democratic decadence and exemplifies a homoerotic, vegetarian, fraternal, and socialistic decadence that combines late-century aestheticism and utopianism with the embrace of a cosmic Whitmanian self and an ardent embrace of Indian spirituality and culture. John Davidson’s poetics are a case-study in muscular decadence with its roots in Nietzsche, the Nietzschean will to power and in a cross-fertilization of German and European pessimism with particularly British ideas of national culture and the great self. Sarojini Naidu’s poetics are a case-study in poly-decadence, a poly-cultural, poly-theistic, and poly-valent poetics that explores the international shape of decadent symbolism and a wide movement toward an emancipatory decadence intertwined with a nationalistic feminism. By organizing and naming the key decadent aesthetic fields that the authors engaged with this study traces the dialectical interplay between poetry and decadent theory during the period and attempts to broaden and complicate how we understand decadence, discourse and aesthetics as key drivers in the production of culture.


identifier: Dhaliwal, Sonia  (2020) Negotiating Identity: Intergenerational Conversations in a South Asian - Canadian Family.  Masters thesis, Concordia University.

abstract: This thesis investigates change over time within a diasporic community in Canada using oral history methodologies with four generations of a South Asian-Canadian family. Using a life story narrative style, the formative experiences of first-generation immigrant parents highlights their pre-migratory social worlds and kinship ties. Their experiences in re-creating cultural practices within the private sphere of their homes and re-establishing kinship networks to socialize their children with their heritage created strong ties to their cultural homeland. The experiences of later immigrant cohorts - the 1.5 generation - indicates how intra-generational experiences differed and influenced parenting practices with their children. By contextualising each generation within the broader history of the diaspora, the community’s growth, and movement around Southern Ontario highlights the emergence of a South Asian ethnoburb. The ethnoburb served as a public sphere steeped in South Asian heritage, blending two cultural worlds, and replicating the diverse experiences of the South Asian diaspora. The ethnoburb also created space within the private sphere of the home to negotiate values between two distinct cultures. By shifting the analysis of agency from fixed points of conflict and reconceptualising notions of age, space, and gender, the granular social navigations indicate on-going negotiations within a transplanted community in Canada.


identifier: Ramadan, Khaled  (2020) Toward Effective Gamification: Lebanese Post-Secondary Students’ Perceptions on the Influence of Game Elements on Motivation to Learn.  Masters thesis, Concordia University.

abstract:
Motivation has been a topic of vast interest in the realm of education for close to four decades. Technological advancements have paved way for concepts such as gamification, a strategy intended to address motivation and engagement with learning, in the world of computerized learning. Notwithstanding, it has not yet been determined precisely what game elements work best to motivate learners when gamifying educational content, and if different types of students prefer certain game elements amongst others. In efforts to investigate those areas, this thesis explores, via surveys, the perceptions of 42 Lebanese post-secondary students on the influence of a specific set of game elements on Keller’s (1987) four components of motivation: attention, relevance, confidence, and satisfaction. Preliminary results showed that the participants perceived an overall positive influence of the selected game elements on motivation. Further analysis revealed that stories and narration topped the list as the most influential game elements on motivation. Minor differences were found in the perceptions of different types of students in terms of their age, gender, level of studies, and the hours they spend gaming per day.
	Keywords: game elements, gamification, motivation


identifier: Rehan, Sana  (2020) Investigating Visual Function and Cortical Structure in Groups with (or at Risk for) Alzheimer’s Dementia.  Masters thesis, Concordia University.

abstract:
Poor sensory performance is cross-sectionally associated with poorer cognition and increases risk for cognitive decline and Alzheimer’s dementia (AD). The purpose of this study was to characterize the degree of visual impairment in individuals with (or at risk for) dementia and explore the effects of this sensory-cognitive relationship on brain structure.

Using the Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND) dataset, we analyzed vision and imaging data from three diagnostic groups: individuals with subjective cognitive decline (SCD; N = 53), mild cognitive impairment (MCI; N = 102), and mild AD (N = 45). We characterized used ANCOVAs to determine whether visual performance on reading acuity and contrast sensitivity differed as a function of clinical diagnosis. Cortical thickness and volume were extracted using FreeSurfer, and hierarchical regression analyses were done to determine whether visual performance predicted brain structure (i.e., cortical thickness and volume) beyond diagnostic group membership.

We found that the AD group performed significantly worse on reading acuity and contrast sensitivity compared to the SCD and MCI groups, which did not differ from each other. Despite our independent findings that visual performance differs across diagnostic groups and that group membership predicted cortical structure, our results demonstrate that visual performance does not predict cortical structure above and beyond clinical diagnosis. Our findings support the hypothesis that atrophy in underlying visual areas and pathways is responsible for the functional vision deficits observed in AD.


identifier: Meertens, Wesley ORCID: https://orcid.org/0000-0002-9233-8249 <https://orcid.org/0000-0002-9233-8249>  (2020) Wastewater Treatment using a Novel Combined Electro-Oxidation, Electro-Coagulation, and Electro-Filtration Process.  Masters thesis, Concordia University.

abstract:
This research designs a novel electrochemical wastewater treatment reactor, combining Electro-Oxidation (EO), Electro-Filtration (EF), and Electro-Coagulation (EC), which was then evaluated through the anti-fouling capabilities of EF and through the removal capabilities for dye materials and Chemical Oxygen Demand (COD). The reactor is facile, does not require chemical additions, has minimal training requirements, is modular, and plainly removes contaminants.
The main findings showcase the capabilities of this novel reactor design, the anti-fouling characteristics of a conductive membrane, and the enhanced removal capacities of electrochemical wastewater treatment as compared to the popularized membrane processes. The normalized flux decrease due to fouling was around 20.51% for the standalone UF processes, compared to an average normalized flux decrease of 9.99% for EO-EF and 33.44% for EO-EC-EF reactor set ups. This shows the anti-fouling capabilities of a conductive membrane, as the average normalized flux decrease was more than half in the EO-EF set up, as compared to the UF set up. Methylene blue removal was around 33% for the UF set up, whereas it was over 95% for all electrochemical reactor set-ups. Finally, for COD removal, UF removed around 12% as compared to an average 77% removal rate using electrochemical processes. These improved removal capacities and flux ratings when using electrochemical processes have validated the reactor designs while confirming the anti-fouling and removal abilities of electrochemical wastewater treatment designs. At the time of submission, this combination of electrochemical processes has not been investigated to the best of our knowledge.


identifier: Kann, Taylor  (2020) Horsepox and Hype: A Science Journalism Experiment.  Masters thesis, Concordia University.

abstract: This thesis utilized model-based test journalism (Amend, Capurro and Secko 2014) to study how synthetic biology was reported by science journalists within a hype context. It explored whether it was possible to create a new model of science journalism which was resistant to critiques of hype. Synthetic biology is a rapidly emerging field of scientific inquiry that seeks to engineer and redesign biological parts and organisms. Many definitions of ‘synthetic biology’ are found in scholarly literature. This thesis defines synthetic biology as “the design and construction of new biological parts, devices and systems, and the re-design of existing natural biological systems for useful purposes with a strong focus on engineering” (Bogner et al. 2014). This project limited its scope to textual journalism focused on synthetic biology vaccine research associated with the threat of bioterrorism. Bioterrorism is cited as a serious concern for harmful outcomes of synthetic biology, including the release of dangerous re-engineered pathogens (Schmidt et al. 2009) and is therefore sensitive to the issue of hype.  Theoretically, this thesis built on past research into models of science journalism (Secko, Amend and Friday, 2012), expanding this work to address issues of hype in science journalism production. Methodologically, this thesis recruited four professional science journalists to create test stories that varied in their approach to hype, followed by analyzing how this journalism was read and perceived by non-specialist audience focus groups. The results show that the communication of synthetic biology could be improved moving forward by altering the criteria surrounding hype in textual journalism that was developed for this thesis to include issues of scientific language, purposes of research and intended uses of new technologies. The outcomes of this thesis will prove useful in the design of hype resistant guidelines that will help address the major challenge of misinformation in science journalism.


identifier: Thompson, Margaret  (2020) Getting the Most Out of Known Unknowns: How the Access to Information Act Impacts Journalistic Practice.  Masters thesis, Concordia University.

abstract:
The Access to information Act (ATIA) is an essential yet inadequate piece of legislation that, in theory, helps to facilitate democratic engagement. Making use of this legislation is an essential way for journalists to hold power to account, to provide the public with newsworthy information, to illuminate government officials’ decision-making processes, to verify information gained from other sources and to provide context for their readers.

Unfortunately, the challenges of navigating the ATIA pose significant setbacks for journalists. The most notable examples of these challenges include excessive delays, redactions, fees, and an inefficient complaints process. The inability to gain access to meaningful government information in a timely and cost-efficient manner deeply affects the quality of journalism that can be produced.
These practical challenges are combined with a financially strained news industry where fewer full-time journalists must accomplish more than their predecessors, with fewer available resources. There are multiple negative effects because of these issues: The ATIA is not being used to its fullest extent, the quality of journalism being produced is hampered by incomplete information, and the ability of citizens to make informed choices in the political sphere is obstructed.

This research addresses the lived experiences of journalists who navigate the ATIA as part of their journalistic practice. By drawing on original interviews, this thesis presents a thematic analysis of the most pressing issues that journalists face, as well as the most successful strategies that can be employed by journalists and the general public alike to gain access to government information.


identifier: Fusco, Michael  (2020) RuPaul’s Drag Race en français: The Influences of Modern LGBTQ Media Translation on Queer Identity and Visibility.  Masters thesis, Concordia University.

abstract: Since the recent advent of over-the-top media services, such as Netflix and other internet-based streaming platforms, the very way in which media content is consumed and broadcasted has changed drastically. This thesis investigates the specific ways in which modern LGBTQ media translation influences queer identity. Its framework is based on the idea that language plays an important role in the construction of identity. It relies on the concepts of power (Michel Foucault), performance (Judith Butler), agency (Luise von Flotow) and community (Keith Harvey). Through a comparative English-to-French translation case study of seasons eight and nine of the series RuPaul’s Drag Race, I present eight trends in translation that influence queer identity: the conceptualization of drag; the employment of English lexicon; the transposition of grammatical gender markers; the diminishment of queer source material through mistranslation and omission; the enrichment of queer source material; the alteration of register; the treatment of transgender lexicon; and the transformation of reclaimed vocabulary. I argue that, for gender and sexual minority groups, these translation trends have real and important influences on the evolution of queer identity and the visibility of various LGBTQ communities.


identifier: Kapadia, Jay  (2020) Measurement of Ribozyme Cleavage Reaction Using Toehold Mediated Strand Displacement; Design, Validation and Possible Applications.  Masters thesis, Concordia University.

abstract:
Non-coding RNAs or ncRNAs are RNA molecules that are not translated but play functional roles within cells. Some of these ncRNAs possess enzymatic properties. These molecules are termed as ribozymes. Ribozymes mainly catalyze nucleic acid strand scission reactions with or without the help of protein molecules. Ribozymes such as hammerhead ribozymes (HHRs) are known to mediate gene silencing and RNA processing. Single stranded RNA/DNA (ssRNA/DNA) inducible HHRs or tetracycline inducible aptazymes exist. Using these HHRs, different types of logic gates can be designed, activated by one or more inputs including ssDNA and ssRNA. Evaluating HHR kinetics of cleavage is essential to understand their mechanism, characterize HHR mutants and to properly estimate several parameters important to design RNA-based logic circuits.
Firstly, we developed a novel methodology to detect HHR kinetics using toehold mediated strand displacement reaction (TMSDR). A probe composed of a fluorophore and a quencher was designed to measure the kinetics of HHR cleavage reactions without labelling RNA molecules, regular sampling or the utilization of polyacrylamide gels. This probe consists of two DNA strands; one strand labelled with a fluorophore at its 5′ end, while the other strand labelled with a quencher at its 3′ end. These two DNA strands are complementary, but the fluorophore strand is longer than the quencher strand at its 3′. The unpaired extra nucleotides act as toehold, which is utilized by a detached cleaved fragment, coming from a self-cleaving hammerhead ribozyme, as the starting point for the strand displacement reaction. This reaction will cause the separation of the fluorophore strand from the quencher strand, culminating in fluorescence detectable in a plate reader. This fluorescence is proportional to the amount of detached cleaved-off RNA strand displacing the DNA quencher strand. This method can be used to replace radio-hazardous unstable 32P as a means of measurement of the kinetics of ribozyme cleavage reactions; it also eliminates the need for use of polyacrylamide gels for the same purpose. Critically, this method allows experimenters to distinguish between the amount of cleaved ribozyme and the amount of detached cleaved-off fragments, resulting from the cleavage.
Secondly, we developed doubler HHRs that cleave twice upon induction with a single input strand (ssDNA/ssRNA). Outputs can be heterogeneous (Hetero doubler) or identical (Homo doubler). Homo doublers were designed to work as amplifying components in RNA amplifiers. We showed two potential doubler HHRs from two different designs (First doubler and D1 doubler). In conclusion, we found that the concentration of detached cleaved-off fragments is relatively low and hence we developed homo-doublers to increase the concentration of cleaved-off fragments.


identifier: Heydari, Atefeh  (2020) Walking through the gardens: A case study of Iranian community gardeners in three urban community gardens, in Montreal, Canada.  Masters thesis, Concordia University.

abstract: This thesis examines the place-making strategies employed by some Iranian immigrants in three urban community gardens in Montreal, Canada. I argue the practices of place-making within the garden is a complex and multilayered process in which heterogeneous actors (human and non-human) play central roles. Prosaic pleasures invoked through enchanting encounters and childhood memories of a beloved garden motivate some people to spend their time and energy within the garden in the hope of re-enchantment. In this theoretical synthesis, I examine how, through inhabiting the garden, these gardeners develop a sense of belonging and attachment to Canada as their new home. I demonstrate that place-making within a community garden goes beyond altering the physical landscape of the garden. Through the process of constructing an alternative home within the community garden, immigrants form family-like relationships, improve their health and well-being, and also cultivate a sense of stability and belonging. This thesis examines the entangled relationships between humans and non-humans within the community gardens. I propose that place-making within the community garden is not just a human achievement, but rather it is co-constructed by heterogeneous actors. It is notable that this thesis acknowledges that a human is the most powerful actant in the process of place-making. However, it also highlights the roles of non-humans as it would be a huge omission if we did not credit the active positions of non-humans in our lives.


identifier: Switzer, Andrew Clark  (2020) From Me to You: Stress Spillover and Respiratory Sinus Arrhythmia.  Masters thesis, Concordia University.

abstract: Stress spillover describes how stress in one life domain affects other life domains. For example, parenting stress, defined as stress related to raising a child, tends to affect how romantic partners think about, feel, and behave in their romantic relationship with their spouse. Evidence suggests that, on average, parents of young children experience a decline in romantic relationship quality as they transition into parenthood. However, not all parents experience stress spillover from their child-related stress to their romantic relationship. This study evaluated whether respiratory sinus arrhythmia, a biomarker of emotion regulation capabilities in interpersonal relationships, moderates the effect of child-related stress on marital stress among parents of young children. As part of a dyadic study, 82 cohabiting couples raising preschool aged children had their resting RSA assessed during a laboratory visit, and independently reported on their daily child-related stress and marital stress for seven consecutive days. Actor partner interdependence modelling tested the associations between child-related and marital stress for both members of the couple, as well as the moderating role of each partners’ RSA. Results indicated significant actor and partner effects of child-related stress on actor marital stress. These results show that one partner’s reports of child-related stress were related to their own reports of marital stress and to their partner’s reports of marital stress, even after adjusting for their partner’s reports of child-related stress, indicating the presence of a stress spillover effect. Furthermore, a significant interaction between partner’s reports of child-related stress and partner’s RSA when predicting actor’s marital stress revealed that this stress spillover effect was larger among individuals with lower RSA. Our findings suggest that RSA influences the extent to which parenting stress impacts one’s interpersonal behaviours in their romantic relationship.