title: Ecological Modernization and Canada's Energy Debate: Reconciling Economic, Environmental, and Political Agendas?

contributor:
Department of Political Science
Master of Arts
Dr. Katherine Fierlbeck
Dr. David Black
Dr. Ruben Zaiotti
Dr. Katherine Fierlbeck
Dr. Anders Hayden
Not Applicable
Not Applicable
Not Applicable

subject:
Energy
Energy Policy
Canadian Politics
Ecological Modernization
Green Economy
Canadian Energy Policy

abstract:
Like many modern industrialized nations, Canada is grappling with the need to maintain a stable, growing economy and to take meaningful action on climate change by reducing greenhouse gas (GHG) emissions. This is particularly challenging in a resource-based economy and federalist state like Canada, where competing regional interests and a historical dependence on oil has made it difficult to legislate and implement long-term energy and climate change policies. Two visions for energy development in Canada have emerged within public discourse. The first advocates the continued and expanded development of Canada’s oil sands and new pipeline infrastructure to access overseas energy markets. The second proposes a re-conceptualization of the Canadian energy sector based on a phasing out of carbon-based fuels and expanded use of renewable alternatives to support a thriving green economy and meet international climate change obligations. Both visions promise an environment-economic win-win scenario where Canada’s growth imperative can co-exist harmoniously with sustainable environmental policy.
Ecological Modernization (EM) theory is a school of thought which maintains that decoupling economic growth from its environmental impacts is possible through technological and institutional modernization processes. This thesis examines both visions of energy development through the lens of EM theory to determine the likelihood of each in achieving environmental, economic and political reconciliation. EM has been successful in helping to frame and understand how industrialized societies are changing their views of the environment and incorporating ecological considerations into policy decisions. However, this thesis finds that the current political climate in Canada remains unfavourable to the transformative institutional reforms necessary to implement a truly ecologically modern national energy strategy. From the Canadian perspective, EM’s promise of an environmental-economic “win-win” scenario appears to be outweighed by political challenges.


title: THE HURDLES OF MEDIATING WITH HUMANITARIAN LENS: AN EXPLORATION OF THE INTER-GOVERNMENTAL AUTHORITY AND DEVELOPMENT’S FAILED SOUTH SUDAN 2015 PEACE AGREEMENT

contributor: Department of International Development Studies

subject: South Sudan

subject: Intergovernmental Authority on Development

subject: Peace mediation

subject: Mediating with humanitarian lens

abstract: This thesis examines IGAD humanitarian focused mediation in the South Sudanese conflict that blames the warring parties entirely for failing to end the war. It particularly looks at mediation strategies deployed by IGAD and its partners as they push to address the humanitarian situation in South Sudan, and how this approach created hurdles during the negotiations process and even at the implementation phase after the parties were compelled to sign the agreement. My investigation of IGAD mediation departs from the story of unwilling warring parties who do not want to sign a peace agreement and save lives presented by IGAD by taking a holistic look at the effect of IGAD mediation timing on parties’ military expectations as well as the effect of the IGAD member states strategic consideration on their ability to enforce disputants’ compliance during the negotiations, and even at the implementation phase of the agreement. I concluded that the timing of the intervention and the agreement the disputants were compelled to sign were at odds with military expectation of the warring parties, specifically those of the government.


title: Testing the Effectiveness of Asset-Based Community Development (ABCD) as a Tool for Non-Governmental Organizations (NGOs) to Increase Supports for Refugee Claimant Integration: A Case Study of the Halifax Refugee Clinic (HRC).

abstract: Key words: asset-based community development, non-governmental organizations, participatory action research, refugee claimant, refugee integration, ABCD, NGOs, PAR.

abstract:
Non-Governmental Organizations (NGOs) are the main service providers for refugee claimant integration in Canada. However, these NGOs often have limited internal capacities and there is an increasing number of refugee claimants relying upon their services. There is concern if NGOs can support the growing demand for their services, with the current government supports and their limited internal capacities. This study considers the potential for Asset-Based Community Development (ABCD) to help NGOs increase their internal capacities to improve the services they offer. The research uses Participatory Action Research (PAR) methods to conduct a case study with the Halifax Refugee Clinic (HRC). A focus group and key informant interviews informed a Strengths, Opportunities, Weaknesses and Threats (SWOT) analysis of the HRC. The results of the SWOT analysis were used to determine the effectiveness of ABCD in helping NGOs increase their internal capacities. Results indicate that NGOs supporting refugee
claimant integration already operationalize ABCD, however, it is not an effective methodology for increasing their services at this time. The results may differ with the study of a different NGO. The data collection and analysis methods were developed to be able to be easily transferable to other organizations. Further study on the policies and practices of refugee integration in Canada and refugee determination procedures, amendments to the definition of a refugee in the 1951 Convention Relating to the Status of Refugees, and public education are recommended as future actions. The HRC is already working to catalyze action within the organization based on the research findings.


title: How Renewable Energy Initiatives Have Been Successfully Implemented in Morocco

abstract: Most of the literature around transitioning economies to green growth focuses on developed countries because they are assumed to be the only countries that can afford to transition. Morocco, a developing country, has implemented the world’s most ambitious renewable energy plan to diversify its energy mix and reduce the country’s dependence on imported energy. Using document analysis, the data around how Morocco’s renewable energy sector is constructed, collected, coded and evaluated to demonstrate how the sector was established and what legal frameworks govern it.  Morocco recognized that in order to develop its energy sector it needed to liberalize it to attract private and direct foreign investment. Morocco has been able to establish a specialized national agency that focuses on pushing and promoting the renewable energy sector to ensure its growth and development. Morocco has been able to establish a blueprint that other African countries can emulate and strive for.


title: LATE CARBONIFEROUS CYCLOTHEMS AND ORGANIC FACIES IN THE PHALEN-BACKPIT SEAM INTERVAL, SYDNEY COALFIELD, NOVA SCOTIA

contributor:
Department of Earth Sciences
Master of Arts
Paul Schenk
Franco Medioli
Martin Gibling
Not Applicable
Not Applicable
Yes


title: EXPERIMENTAL AND NUMERICAL STUDY OF THE IN-PLANE AND OUT-OF-PLANE BEHAVIOUR OF UNREINFORCED MASONRY INFILLS BOUNDED BY RC FRAMES

contributor:
Department of Civil Engineering
Doctor of Philosophy
Dr Tony Yang
Dr Hany El Naggar
Dr Gordon Fenton
Dr Fadi Oudah
Dr Yi Liu
Not Applicable
Yes
Yes

subject:
Masonry infill
Concrete masonry unit
Concrete frame
Finite element analysis
Experimental study
In-plane behaviour
Out-of-plane loading
Arching action
Nonlinear analysis
Damage
Masonry design

abstract:
A literature review revealed that there is limited technical information available on the subject of masonry infilled frames, in particular, the interaction between the infill and its bounding frame and how this interaction affects the infilled system behaviour and strength. This research was then conducted to further the understanding of the infill-to-frame interaction considering a range of geometric, material, loading characteristics of the infilled frame systems. To that end, both experimental and numerical studies were performed with the focus on the concrete masonry infills bounded by reinforced concrete frames. Both in-plane and out-of-plane loading situations on the infilled frames were considered. The experimental testing was designed to provide physical results of failure modes, behaviour and strength of infilled frames as affected by several key parameters. The numerical study began with development of a 3D finite element model capable of incorporating properties of masonry infilled frames using ABAQUS. An extensive validation process on the model ensued using the physical results. Once verified, the model was used in a finite element study where several geometric and material parameters with extended range of variations were systematically studied.
In the experimental study, a total of 17 specimens were tested of which 1) ten were subjected to in-plane loading; 2) four were subjected to out-of-plane loading; and 3) three were tested under in-plane loading first and then tested under out-of-plane loading to failure. Infill openings and infill-to-frame interfacial gaps were designed as two varying parameters for 1) and 2) test scenarios. The varying in-plane damage was the parameter for 3) testing scenario. While the diagonal cracking followed by corner crushing predominated the in-plane failure, two-way arching with the shear cracking through the concrete masonry unit webs was identified as the main load-resisting mechanism in out-of-plane tests. As for the in-plane damaged specimens, the out-of-plane capacity was reduced as a function of experienced in-plane drift ratio.
In the numerical study, the finite element model was shown to be capable of predicting the load-displacement responses as well as the cracking pattern and failure modes accurately for both in-plane and out-of-plane loading scenarios. The correlations between each studied parameter and the behaviour and strength of masonry infilled frames were presented and discussed. Modifications on the out-of-plane design method currently adopted by the American masonry standard (TMS 402/602-16) were proposed and was shown to improve the performance of the method. A lower-bound equation for evaluating the out-of-plane strength of masonry infills with prior in-plane damage was proposed and it showed to produce better estimate when compared to the existing method.


title: EXTRACELLULAR MITOCHONDRIA RELEASED FROM LIVER ISCHEMIA REPERFUSION INJURY ACT AS ALARMINS TO EVOKE INNATE IMMUNE SYSTEM AND TRIGGER INFLAMMATION

contributor:
Department of Pathology
Doctor of Philosophy
Markus Selzner
Wenda Greer
Karen Bedard
Jean-Francois Legare
Craig McCormick
Jean Marshall
Ian Alwayn
Received
Yes
Not Applicable

subject:
Liver ischemia reperfusion injury
Mitochondrial alarmin
innate immunity
Mast cells
Macrophages

abstract:
Ischemia reperfusion injury (IRI) during liver transplantation enhances the immunogenicity of allografts and thus impacts overall graft outcome. This sterile inflammatory insult is known to activate innate immunity and propagate organ damage through the recognition of endogenous alarmins. The purpose of this study was to investigate the role of mitochondrial alarmins in the pathogenesis of hepatic IRI and the mechanism of immune activation by mitochondria. Mitochondria are vital cellular organelles for energy generation. However, owing to their similarity to bacteria, extracellular mitochondria function as alarmins. Recent studies revealed that mitochondria are critically involved in the initiation and progression of multiple diseases and associated with immune dysregulation. Increased levels of mtDNA and free mitochondria (FM) release were observed in both transplantation-associated and warm IR. Co-culture of mitochondrial components with hepatocytes significantly increased cell death. Mast cells (MC) and Kupffer cells (KC) are versatile immune sentinel cells known to respond to both external and internal stimuli as a first line of defense in liver. However, the response of MC and KC to mitochondria was unknown. Injection of FM into mice led to neutrophil recruitment and macrophage activation within the peritoneal cavity at 16h. MC-deficient mice had significantly reduced neutrophil responses to FM although macrophage activation was still observed. Culture of MC or macrophages with mitochondria resulted in increased production of multiple mediators. FM induced histamine release from human CBMC and mouse BMMC. This degranulation process was rapid and largely independent of extracellular calcium. Pharmacological approaches revealed that FPR1 was important for mitochondria-mediated in vitro degranulation and mediator production, in addition to in vivo sterile inflammation. FM also enhanced macrophage activation, although this was in an FPR1-independent manner. FM were potent activators of both human and mouse innate immune cells, such as MC and macrophages, in vitro and induced substantial MC-dependent, neutrophilic inflammation in vivo.
Regulation of mitochondria-mediated immune responses may be important during the initiation or progression of human disease such as acute graft failure or chronic graft versus host disease in liver transplantation, rheumatoid arthritis, or in patients with blood transfusion, which have all been reported to demonstrate enhanced FM release.


title: Ultra-Low-Power Super Regenerative Receivers for Wireless Communication

contributor: Department of Electrical & Computer Engineering

subject:
super-regenerative oscillator
sensitivity
automatic -gm controller
frequency-locked loop

abstract:
In this Thesis, both low frequency and high frequency ultra-low-power super-regenerative receiver with detailed circuits and system design for wireless communication networks has been proposed in this thesis.

The SRR design has been applied super-regeneration theory which simplifies the receiver circuits implementation without increasing the power consumption and improves sensitivity.  LC-SRO based energy detector, phase-locked loop, frequency locked loop, (PLL, FLL etc), Automatic -Gm controller, high speed, high conversion gain envelope detector (ED) and advanced quenching techniques (OQW, CQW) are presented in this thesis.

This thesis also focuses on how to improve SRR’s sensitivity (including SNR, BER) under high data rate with minimum power consumption. A series of advanced quenching techniques (OQW, CQW) are presented and studied for LC-VCO based SRO. High speed and high conversion gain envelope detector with automatic -gm controller will help the proposed SRR achieves great immunity to PVT variations and improve the data rate. Finally, FLL based frequency calibration techniques allows the SRR improves its sensitivity and selectivity against PVT variations.


title: MICRORNA SPECIES REGULATE IMMUNE PROCESSES: A FOCUS ON NK CELLS IN CHRONIC ARTHRITIS

contributor:
Department of Microbiology & Immunology
Master of Science
Dr. Shashi Gujar
Dr. Brent Johnston
Dr. Thomas Issekutz
Dr. Craig McCormick
Dr. Beata Derfalvi
Dr. Jeanette Boudreau
Received
Not Applicable
Not Applicable

subject:
Natural Killer Cell
MicroRNA
Rheumatoid Arthritis
Transfection

abstract: Rheumatoid arthritis (RA) is a common chronic autoimmune/inflammatory disease involving innate/adaptive lymphocytes and soluble mediators. Natural killer (NK) cells are innate lymphocytes that direct immunity through cytotoxicity and cytokine production. The contributions of NK cells are ill-defined in RA, although their function(s) may be regulated by microRNAs (miRNAs). MiRNAs are non-coding RNAs that inhibit mRNA. To investigate the miRNA-NK cell interplay, we optimized highly efficient transfection techniques in serum-free media for enhancing or interrupting NK cell miRNA signaling. We targeted miRNAs that are expressed differently in patients with RA compared to healthy individuals. Our findings suggest that miR-146a-5p and miR-155-5p, two miRNAs upregulated in RA, reduce NKG2C expression, a hallmark of adaptive NK cells. We expect chronic overexpression of these miRNAs inhibits adaptive NK cells and their ability to eliminate auto-reactive B/T cells through antibody dependent cellular cytotoxicity (ADCC), thereby reducing treatment efficacy for therapies that rely on effective ADCC.


title: PRO-INFLAMMATORY TRANSFORMING GROWTH FACTOR BETA SIGNALLING AS A THERAPEUTIC TARGET FOR REPETITIVE MILD TRAUMATIC BRAIN INJURY

contributor:
Department of Medical Neuroscience
Doctor of Philosophy
Dr. Ramon Diaz-Arrastia
Dr. Kazue Semba
Dr. Alexander Easton
Dr. Sultan Darvesh
Dr. Alon Friedman
Received
Not Applicable
Not Applicable

subject:
traumatic brain injury
concussion
medical neuroscience
neuroinflammation
blood-brain barrier

abstract:
Traumatic brain injury (TBI) occurs in an estimated 50-60 million people annually, making it a major global health concern. Despite growing awareness of the risks associated with repetitive mild traumatic brain injury (rmTBI) and concussion, there remain significant unknowns regarding the mechanisms underlying the acute and delayed complications of these events. Moreover, there are currently no approved therapies for the treatment or prevention of the pathological sequelae of rmTBI.

This thesis sought to investigate the role of pro-inflammatory transforming growth factor beta (TGFβ) signalling in rmTBI and evaluate its potential as a novel treatment strategy for rmTBI-associated complications. To address these questions, I established and characterized a rodent model of rmTBI that recapitulates the clinical spectrum of outcomes that are commonly observed following concussion and mild brain trauma (Chapter 2). To further characterize this heterogeneity, retrospective grouping of animals as “sensitive” to the acute neurological consequences of rmTBI versus those “resilient” to these effects was performed. This approach revealed that acute neurological outcomes of rmTBI were not predictive of delayed deterioration, suggesting that the mechanisms underlying chronic neurological consequences of rmTBI occur in the absence of overt acute neurological signs. In Chapter 3, the mechanisms underlying acute sensitivity to rmTBI were explored. I showed that pathological increases in blood-brain barrier dysfunction (BBBD), TGFβ signalling, reactive gliosis, and neuroinflammation following rmTBI are associated with a more severe clinical outcome (sensitivity) during the acute phases of injury. Thus, I tested the effect of two TGFβ antagonists, IPW and losartan, as therapeutic approaches for the treatment and prevention of rmTBI-associated complications (Chapter 4). While slight differences in effects were observed for each of these treatments, I found that antagonism of TGFβ signalling was successful in improving acute outcomes, including post-impact convulsions and early recovery following injury. Further, antagonism of TGFβ signalling protected the integrity of the blood-brain barrier and prevented delayed neurological and cognitive complications of repetitive injury. Together, my findings highlight the potential of TGFβ antagonism as a future therapeutic strategy for complications of rmTBI.


title: MECHANISTIC INSIGHT INTO THE PROLACTIN-/ANDROGEN-INDUCIBLE CARBOXYPEPTIDASE-D AND EDD E3 UBIQUITIN LIGASE GENES IN TRIPLE-NEGATIVE BREAST CANCER

contributor: Department of Biochemistry & Molecular Biology

subject: Cancer

abstract: Membrane-bound Carboxypeptidase-D (CPD) hydrolyzes C-terminal arginine residues from extracellular substrates. Released arginine, taken into cells, is converted into nitric oxide (NO). Our laboratory has shown that CPD mRNA/protein levels are upregulated by prolactin (PRL), 17β-estradiol, and androgen testosterone in breast cancer (BCa) cells, in turn, increasing NO production to promote BCa cell survival. EDD E3 ubiquitin ligase identified by differential display (EDD) is an E3 ubiquitin ligase protein normally involved in protein turnover, however it is frequently overexpressed in cancer cells. EDD has been implicated by our laboratory in the mammalian-target-of-rapamycin (mTOR) signalling pathway that regulates the initiation of protein translation. Like CPD, EDD protein levels are upregulated by hormones, specifically PRL, progesterone, and synthetic androgen R1881. This study investigated the role of PRL/androgen-inducible EDD and CPD in BCa, particularly in the aggressive triple-negative breast cancer (TNBC) subtype. This was accomplished in vivo by immunohistochemical analysis of EDD in archival human breast specimens as well as examining the effect of high EDD or CPD mRNA expression on the survival probability of BCa patients. A multitude of in vitro experiments were conducted to demonstrate hormonal upregulation of EDD or CPD and the biological effects of altered EDD or CPD gene expression in TNBC cell lines. The present study showed that high CPD mRNA expression in BCa patients correlated with a poorer probability of relapse-free survival. CPD protein expression was upregulated by PRL and R1881 in a time-/dose-dependent manner and was accompanied by increased intracellular NO production, which enhanced TNBC cell survival in vitro. Depletion of CPD from TNBC cell lines using small-interfering ribonucleic acid (siRNA) resulted in decreased TNBC cell viability. EDD immunostaining was shown to be low in benign human breast tissue but increased with breast cancer progression in vivo. High EDD mRNA expression correlated with a poorer probability of overall and relapse-free survival in BCa and TNBC patients, respectively. EDD protein expression was upregulated by PRL and R1881 in a time-/dose-dependent manner in vitro and was speculated to occur at the transcriptional level due to the presence of putative hormone response elements in the EDD gene promoter. SiRNA-mediated knockdown of EDD gene expression induced a variety of effects including decreased TNBC cell viability, increased expression of pro-apoptotic-associated proteins MOAP-1 and Bax, cleavage of Caspase-7 and PARP-1, decreased PRL-/R1881-induced phosphorylation of initiation factor 4E binding protein-1 (4E-BP1), and subsequent 4E release, as well as decreased resistance to anti-cancer drugs. In summary, PRL/R1881-inducible CPD increased TNBC cell survival through the production of NO. EDD levels increased with BCa progression and loss of PRL/R1881-inducible EDD decreased TORC1 signalling, promoted pro-apoptotic protein expression, and decreased anti-cancer drug resistance in BCa cells. Collectively, this work supports EDD and CPD as therapeutic targets for BCa, including TNBC, and suggest that EDD and CPD expression may predict BCa responsiveness to various anti-cancer drug treatments.


title: The Effect of Bacterial High Temperature Protein G on Intestinal Epithelial Cells in the Context of Pediatric Crohn’s Disease

contributor:
Department of Microbiology & Immunology
Master of Science
Dr. John Archibald
Dr. Brent Johnston
Dr. Joseph Bielawski
Dr. John Rohde
Dr. Andrew Stadnyk
Not Applicable
Not Applicable
Not Applicable

subject:
Bacteroides
Crohn's Disease
Microbiome
Hight temperature protein G
Exclusive Enteral Nutrition

abstract: Crohn’s disease (CD), a type of inflammatory bowel disease, is caused by environmental, microbial, genetic, and immunological factors. Increased expression of specific heat shock proteins (HSPs) in CD patients protects intestinal epithelial cells (IECs) from death. High temperature protein G (HtpG), a gene encoding a bacterial HSP, is less abundant in pediatric CD patients than in healthy individuals. The role of HtpG in CD is poorly understood, thus I sought to describe HtpG activity on the innate immune response of IECs. I used metagenomic sequencing data to determine that only certain HtpG lineages appear in the intestines. By measuring IEC inflammatory mediators, I observed HtpG to be inflammatory, but with the capacity to dampen the effects of another inflammatory molecule, tumor necrosis factor. I also identified, by co-affinity purification, that HtpG interacts with three common CD-associated gene variants. These results suggest HtpG acts extra- and intra-cellularly to mediate inflammatory signaling.


title: Buyer behaviour toward Instagram based businesses in Saudi Arabia

contributor:
Faculty of Computer Science
Master of Electronic Commerce
Vlado Keselj
Sandra Toze
David Roach
Joyline Makani
Received
Not Applicable
Not Applicable

subject:
Instagram
E-commerce
Social Media
Online buyer behaviour
Impulse buying
Vision 2030
Social commerce

abstract:
This study explores the behavior of buyers in Saudi Arabia. Primarily, buyers who
are using Instagram to purchase from new types of e-businesses; businesses that use
Instagram as their only platform for commerce. The objectives include, help achieve a
better understanding of Saudi consumers, suggest how social media businesses can better
design their business accounts to promote trust and increase their customer base, help
direct future government, public, or private investments, and to participate in reaching the
goals and objectives of Vision 2030 in the country. Based on existing literature and
theories related to buyer behaviour, including the theory of planned behavior, and the
impulse buying behaviour, an online survey was distributed to Saudi Instagram users, to
investigate the factors that affect their purchasing decision process with relation to ecommerce
businesses that are based on Instagram. 530 participants took part in this
study, and it was found that some demographic factors play a role in encouraging the
purchasing act, while impulse buying factors do not seem to make a big difference. In
addition, factors related to brand trust, product features, customer service, and payment
methods are the core elements that drive the consumers in Saudi Arabia to buy from these
businesses.


title: Identifying Novel Effectors of Breast Cancer Stem Cell Population Equilibrium and Survival

contributor:
Department of Pathology
Master of Science
Dr. Kerry Goralski
Dr. Wenda Greer
Dr. Andrew Stadnyk
Dr. Sidney Croul
Dr. Adrienne Weeks
Dr. Paola Marcato
Received
Not Applicable
Not Applicable

subject:
breast cancer
cancer stem cells
long non-coding RNA

abstract: Triple negative breast cancer (TNBC) patients face poor survival outcomes possibly due to the presence of a small, yet aggressive population of cells termed cancer stem cells (CSCs). In breast cancer, CSCs are defined either by high Aldefluor activity or CD44+/CD24- status. To aid the development of efficient CSC-targeted therapies, it is vital to unravel the relationship between these two CSC populations. Here, we explore this relationship showing that these two populations of breast CSCs are not independent. Furthermore, we suggest a novel approach for targeting CSC populations involving inhibition of long non-coding RNAs (lncRNAs). We assess the importance of a lncRNA termed prostate androgen regulated transcript 1 (PART1) in TNBC. We found that PART1 is enriched in both TNBCs and CSCs populations, confers a survival advantage to TNBC cells and maintains CSC pools. Therefore, we present PART1 as a novel therapeutic target that may be capable of targeting CSC populations.


title: THE INFLUENCE OF BREASTFEEDING ON PAIN-RELATED EVENT-RELATED POTENTIALS AND BIO-BEHAVIOURAL INDICATORS OF PROCEDURAL PAIN IN NEWBORNS: A RANDOMIZED CONTROLLED TRIAL

contributor:
School of Nursing
Doctor of Philosophy
Liisa Holsti
Marilyn MacDonald
Margot Latimer
Aaron Newman
Ruth Martin-Misener
Marsha Campbell-Yeo
Received
Not Applicable
Not Applicable

subject:
breastfeeding
24% oral sucrose
pain
pain assessment
event-related potential
bio-behavioural pain scores
neonates

abstract:
Background: Breastfeeding and oral sucrose have strong evidence for reducing infant bio-behavioural responses to pain, however, no studies have compared the effect of these interventions on pain-related electrophysiologic brain activity.

Aims: To examine the influence of breastfeeding on pain-related electroencephalographic activity in newborns during heel lance, compared to 24% oral sucrose. Secondary aims were to compare a) bio-behavioural pain scores (Premature Infant Pain Profile – Revised [PIPP-R]), b) physiologic recovery, c) maternal acceptance, and d) adverse events between groups.

Methods: Healthy full term normally breastfeeding infants (n = 39) were randomly assigned to be breastfeeding or to receive 0.24 mL of 24% oral sucrose plus offered nonnutritive sucking two minutes prior to heel lance. Pain-related potential time-locked to heel lance was recorded on neonatal electroencephalogram and isolated using principal component analysis. Secondary outcomes of PIPP-R at 30-, 60-, 90-, and 120-seconds following heel lance and physiologic recovery were measured using continuous video and pulse oximeter recording. Maternal acceptance was measured using a study-specific questionnaire. Occurrence of adverse events were documented throughout study procedures. Data were analyzed per protocol as registered on ClinicalTrials.gov: NCT03272594.

Results: Twenty infants were randomized to the breastfeeding group and 19 infants to the oral sucrose group. Infants who received oral sucrose had an appreciably larger, yet not statistically significantly different (F[1,15.9] = 0.58, p = 0.64, SE = 11.79), amplitude pain-related potential (peak amplitude 8.97 μV) following heel lance compared to breastfeeding infants (peak amplitude 0.29 μV). Mean PIPP-R scores were not statistically significantly different between groups following heel lance, however, they were indicative of low to no pain across groups. Mean time in seconds to physiologic recovery was faster in breastfeeding infants (M = 17.5, SD = 31.1) compared to oral sucrose (M = 70.8, SD = 144.3). Mothers reported positive perceptions of the interventions pain-reducing effects and study participation.

Conclusions: Breastfeeding and oral sucrose may differentially modulate pain response in the infant brain. Continued use of these interventions to reduce bio-behavioural pain scores during clinical procedures is warranted. Further research to advance measurement and interpretation of diverse indicators of procedural pain in infants is needed.


title: SYRUP: A NOVEL INVERSION METHOD FOR AEROSOL SIZE-DISTRIBUTION PROPERTIES FROM OPTICAL AND CHEMICAL MEASUREMENTS OF PM2.5

contributor: Department of Physics & Atmospheric Science

subject:
Physics
Radiative Transfer
Remote Sensing

abstract:
Accurate knowledge of aerosol mass scattering efficiency (αsp) is essential to the realistic simulation of
aerosol radiative forcing effects on climate as well as to the visibility influences of aerosols and also to
the interpretation of satellite data. The comparison between measurement and simulation of αsp may
act as a prognostic factor in determining how accurately a model is representing optical characteristics
and size-distribution parameters for aerosols. This study deals with improving representation of the latter
parameters through the development of an inversion algorithm of αsp which yields size-distributions.
Through the deployment of 5 measurement sites across Canada the measurement of PM2.5 (Particulate
matter under a mean diameter of 2.5 μm) mass and chemical composition through filter-sampling stations
was conducted from 2017 to 2019. Concurrently at all sites a 3-wavelength integrating nephelometer
measured ambient scattering. By performing a multiple linear regression (MLR) on the data-set, the αsp
values for the 5 bulk chemical components of PM2.5 are derived. Utilizing the wavelength sensitivity of
αsp, an algorithm is developed that inverts the measurements for aerosol size-distribution properties. The
dry geometric mean diameter (Dpg) of organics, secondary-inorganics, black carbon, sea-salt, and dust is
found to be 0.56, 0.62, 0.54, 0.46, and 0.51 μm, respectively. The variance of these distributions (σg),
ordered as above, is found to be 1.45, 1.30, 1.28, 1.61, and 1.63, respectively (Unitless). The increases
in dry diameter compared to values previously used in radiative transfer models is corroborated by the
results of scanning mobility particle sizer data. These revised representations of aerosols size-distributions
will enable more accurate modeling of radiative processes involving aerosols.


title: MANAGEMENT OF POWDERY MILDEW OF STRAWBERRY (FRAGARIAE × ANANNASA) BY THE APPLICATION OF ASCOPHYLLUM NODOSUM EXTRACT

contributor:
Faculty of Agriculture
Master of Science
Dr. Gordon Price
Dr. Kris Pruski
Dr. Samuel Asiedu
Dr. Balakrishnan Prithiviraj
Not Applicable
Yes
Not Applicable

subject:
Ascophyllum nodosum extract
powdery mildew
P. aphanis
phenylalanine ammonia lyase
Strawberries

abstract: Strawberry, an important fruit crop, is susceptible to a number of pathogens, which leads to a reduction in its productivity. Ascophyllum nodosum extract (ANE) is widely used as biostimulant. In this study, I evaluated the effect of ANE on powdery mildew of strawberry. The progression of disease was significantly reduced in ANE sprayed leaves in both detached as well as greenhouse-grown plants. In laboratory conditions, application of 0.2 % ANE showed maximum reduction in powdery mildew progression as compared to the control plants. ANE sprayed leaves showed higher phenolic and flavonoid content in response to powdery mildew infection. Furthermore, ANE application elicited defense response by inducing the activities of defense-related enzymes. Under field condition, ANE reduced the natural incidence as well as disease severity of powdery mildew. These results indicate that the ANE application increases the strawberry plant’s active defense against powdery mildew by regulating the activities of defense-related enzymes.


title: Associations Between the Presence or Absence of a Lifetime History of Prostate Cancer Diagnosis and Current Mental Health Issues in a Sample of Canadian Men: A Secondary Analysis of the Canadian Longitudinal Study on Aging (CLSA)

contributor: Department of Community Health & Epidemiology

subject:
mental health
Prostate--Cancer.
quality of life

abstract: The present study examined the prevalence of lifetime history of prostate cancer (PCa) in a cross-sectional sample of Canadian men (N = 25, 183) and investigated the contribution of presence or absence of history of a PCa diagnosis to current mental health outcomes. This study used baseline data from the Canadian Longitudinal Study on Aging (2010-2015). Logistic regression analyses, controlled for the complexity of the design, demographics, and lifestyle factors, evaluated the association between history of a lifetime PCa diagnosis and current mental health outcomes. The prevalence of lifetime history of PCa diagnosis in this sample was 4% (95% CI: 3.7, 4.4). Our results indicate statistically significantly greater odds of psychological distress (aOR= 1.52, 95% CI: 1.09, 2.11) and depressive symptoms (aOR = 1.24, 95% CI: 1.02, 1.51) among Canadian men who self-reported a lifetime history of PCa diagnosis, compared to men with no history of a PCa diagnosis, even when multimorbidity and substance use were statistically controlled.


title: THE ROLE OF MITOCHONDRIAL ANTIOXIDANT ENZYME SUPEROXIDE DISMUTASE 2 (SOD2) IN PLURIPOTENCY AND DIFFERENTIATION

contributor:
Department of Pathology
Master of Science
Dr. Patrice Cote
Karen Bedard
Dr. David Hoskin
Dr. Graham Dellaire
Dr. Shashi Gujar
Dr. Tanveer Sharif
Not Applicable
Not Applicable
Not Applicable

subject: Cancer Antioxidants

abstract: The mitochondrial antioxidant enzyme superoxide dismutase 2 (SOD2) is important for maintaining mitochondrial integrity and keeping the levels of reactive oxygen species (ROS) low. Small populations of poorly-differentiated cells with stem-like properties, termed cancer stem-like cells (CSLCs), have been identified in tumor masses and play an important role in chemoresistance and cancer recurrence. The purpose of this study was to examine the role of SOD2 in CSLCs. Using several models of CSLCs including: embryonal CSLCs, breast CSLCs (BCSLCs), and patient-derived brain tumor-initiating cells (BTICs), it was found that silencing of SOD2 inhibits the expression of stemness-maintaining pluripotency factors. Furthermore, the comparison of CSLCs with their non-stem like counterparts revealed that CSLCs harbor drastically higher levels of SOD2. Further mechanistic analysis demonstrated that SOD2 depletion promotes apoptosis and induces differentiation in CSLCs. In conclusion, CSLCs appear to rely on SOD2 expression for maintaining their stem-like features.


title: Adaptive and neutral genetic variation in spring- and fall-spawning herring (Clupea harengus L.) in the Northwest Atlantic

contributor:
Department of Biology
Doctor of Philosophy
Sean Rogers
Sophia Stone
Paul Bentzen
Ian Bradbury
Robert Beiko
Daniel Ruzzante
Not Applicable
Yes
Yes

subject:
Population genomics
Fisheries management
Genetic variation
Ecological adaptation

abstract: Understanding the factors influencing the spatial distribution of intraspecific diversity is both a fundamental goal in evolutionary biology and necessary for the design of robust management strategies for harvested species. Intraspecific diversity can now be assessed using novel genomic techniques that enable the high-density screening of neutral and adaptive genetic variation. In this thesis, I used whole-genome resequencing of pooled DNA of Atlantic herring (Clupea harengus) to (i) identify patterns, genomic regions, evolutionary processes and environmental variables involved in the origin and maintenance of population divergence and local adaptation in the northwest Atlantic, and (ii) develop a diagnostic genetic tool that can inform conservation and fisheries management. I found fine-scale population structure in herring at putatively adaptive loci, despite low differentiation at neutrally evolving loci. Populations were distinguishable by spawning time and along a latitudinal cline defined by winter sea-surface temperature. Divergent selection leading to adaptation to seasonal reproduction and spawning at different latitudes is likely maintaining molecular divergence patterns for these traits in this environment. Each pattern was underpinned by thousands of outlier SNPs distributed in specific genomic regions spanning several candidate genes, some with a known role in the timing of reproduction (i.e. TSHR). Many spawning time-associated SNPs were shared with populations across the ocean, suggesting such adaptation predates the last glacial maximum. Finally, I developed and evaluated the efficacy of two cost-effective SNP-panels diagnostic of spawning season and latitudinal origin. Individual genotypes at these loci confirmed temporal stability of genetic differences among northern populations and between reproductive strategies despite their mixing outside of the spawning season, suggesting spawning time and site fidelity in ecological time scales. Admixture between reproductive and latitudinal components is unrestricted, and the proportion of admixed individuals vary across aggregations. Some individuals with intermediate admixture levels spawned in either season, suggesting that spawning time is not completely fixed. The analysis of mixture samples revealed the dynamic composition of aggregations outside of the breeding season and demonstrated the utility of the SNP-panels for mixed stock assessment. Altogether, these results contribute to the hypothesis that selection influences spatial distributions of genetic variation, highlighting the need to manage or conserve ecologically important adaptive variation in nature.


title: TIME-SERIES FORECASTING USING FEATURE BASED HYBRID APPROACH

contributor:
Faculty of Computer Science
Master of Computer Science
Dr. Michael McAllister
Dr. Luis Torgo
Dr. Evangelos Milos
Dr. Stan Matwin
Dr. Rita Orji
Not Applicable
Not Applicable
Not Applicable

subject:
Time series
Forecasting
Forecast combination
Time series features
Hybrid Approach

abstract: We carried out our research using NN3 dataset and a large subset of 48,000 real-life monthly time series used in the M4 competition, which is characterized by considerable seasonality, trend and a fair amount of randomness so as to cover a wide range of time series structures. Our result reveals that the combination of decomposition, Exponential smoothing, Machine learning methods, and feature extraction gives less forecasting errors when compared to other combinatory approach and benchmark classical approach.

abstract: In this research, we explored the unique strengths of both traditional statistical method and machine learning algorithms to propose a hybrid forecasting system based on a decomposition approach, with the objective of improving forecast accuracy across multiple forecasting horizons. Our proposed methodology uses the Seasonal and Trend decomposition using Loess decomposition procedure to break down time-series data into trend-cycle, seasonal and covariance stationary components, where these components produce individual forecasts and these forecasts are aggregated back to whole using an aggregation procedure, with the sole purpose of minimizing errors. Various types of Exponential Smoothing algorithms were employed for the trend-cycle, seasonal components because of its unique weight combination approach while vectors of features were extracted automatically from the nonlinear covariance stationary subseries to create appropriate Machine Learning models.


title: Low-Power Staircase Encoder Implementation for High-Throughput Fiber-Optical Communications

subject:
Staircase Codes
VLSI
Fiber-Optical Communications

abstract: This thesis presents a very large scale integration (VLSI) architecture of a high-throughput, low latency and power staircase forward error correction (FEC) encoder. The designed encoder achieves low latency and memory overhead by splitting the parity generation matrix and pre-computing partial parity bits for the next staircase block while generating the current staircase block. The proposed encoder is designed with multistage pipelined architecture that enables high efficiency in terms of throughput and area. The proposed staircase encoder was synthesized using 65nm CMOS technology. The throughput of the encoder achieves 432Gbps when operating at 909MHz, with the power consumption of 323mW.


title: ON THE ROLE OF SUB-ANESTHETIC KETAMINE FOR POST-OPERATIVE ANALGESIA FOLLOWING THIRD MOLAR SURGERY

contributor:
Oral & Maxillofacial Surgery
Master of Science
Kathy Drews
Dr. James Brady
Dr. Orlando Hung
Dr. Benjamin Davis
Received
Yes
Yes

subject:
Ketamine
Sedation
Anesthesia
Third Molar
Oral Surgery
Maxillofacial Surgery
Dentoalveolar surgery

abstract: MSc Thesis

abstract: The role of ketamine in post-operative pain following third molar surgery is unclear. Therefore, one hundred and thirty-four patients were enrolled into a randomized double-blinded clinical trial to investigate if patients undergoing third molar surgery who receive a sub-anesthetic pre-operative dose of intravenous ketamine will experience less post-operative pain. The primary outcome was post-operative pain intensity as determined by 10-point visual analogue scales (VAS) during the first 48-hours post-op. The secondary outcome was post-operative non-opioid and opioid consumption. Data analysis involved descriptive statistics, multivariate analysis, and regression analysis. There was a small, yet statistically significant (P<0.05) difference in median pain score at 6-hours post-operatively with the ketamine group experiencing more pain. However, no further differences were detected at any post-operative time between groups. Overall, this study did not find evidence that pre-operative sub-anesthetic ketamine reduced pain following third molar surgery, nor had any effects on non-opioid or opioid analgesic consumption.


title: Compromised Tweet Detection Using weighted sub-word embeddings

contributor:
Faculty of Computer Science
Master of Computer Science
Michael McAllister
Dr. Srinivas Sampalli
Dr. Malcolm Heywood
Dr. Nur zincir-Heywood
Not Applicable
Not Applicable
Not Applicable

subject:
Natural Language Processing
Machine Learning
Security Management

abstract: Extracting features and writing styles from short text messages for compromised tweet detection is always a challenge. Short messages, such as tweets, do not have enough data to perform statistical authorship attribution. Besides, the vocabulary used in these texts is sometimes improvised or misspelled. Therefore, in this thesis, I propose combining four feature extraction techniques namely character n-grams, word n-grams, Flexible Patterns and a new sub-word embedding using the skip-gram model. The proposed system uses a Multi-Layer Perceptron to utilize these features from tweets to analyze short text messages. This proposed system achieves 85\% accuracy, which is a considerable improvement over previous systems. Furthermore, Siamese networks are employed to model the representation of user tweets in order to identify them based on a limited amount of ground truth data. The results show that the proposed system achieves a promising accuracy as the number of authors increase.


title: Distilling an Industry: Re-engaging the Community of Bell Island through Small-Scale Industry

contributor:
School of Architecture
Master of Architecture
Anne Cormier
Steve Parcell
Christine Macy
Diogo Burnay
Not Applicable
Not Applicable
Not Applicable

subject:
Social Sustainability
Newfoundland
Economic Sustainability
Bell Island
Agency
Small-scale Industry
Gin Distillery

abstract:
The province of Newfoundland and Labrador presents many outlets for resources and innovation. Unfortunately, outdated technology and economic downturns have rendered many communities economically vulnerable.

The community of Bell Island, Newfoundland, was once one of the largest iron-ore exporters in the world. Since the closing of the mines in the 1960s, Bell Island’s population has dwindled and its lack of industry is just one example of a recurring economic pattern. While large-scale industries have garnered the hope of renewed economic benefits to the province, Newfoundland has often fallen privy to the contentious politics behind such distant projects.  In order to revitalize and sustain the community of Bell Island, this thesis takes stock of local resources and proposes a strategy that returns small-scale industry based on local knowledge of skill and place, in this case adaptively reusing a barn, that was part of the mining operations, into a gin distillery.


title: VISUAL ANALYTICS OF RESEARCH COMMUNITY EXPERTISE IN SPACE AND TIME

contributor:
Faculty of Computer Science
Master of Computer Science
Michael Mcallister
Vlado Keselj
Luis Torgo
Evangelos Milios
Fernando Paulovich
Received
Not Applicable
Not Applicable

subject:
classification
machine learning
visual analytics
text analytics

abstract:
Association for Computing Machinery (ACM) is an international learned society for computing. ACM operates the Distinguished Speaker Program (ACMDSP). ACMDSP maintains a list of speakers, who can be invited to deliver lectures on Computer Science topics at different locations worldwide. Currently, speakers' lectures are classified into topics manually and ACMDSP committee accesses the speaker and lecture data directly through the database. This thesis is attempting to make it more intuitive to access the database through a visualization system, and in classifying the lectures on offer into topics. It uses Google Map to visualize the speaker, topic and lecture data. It displays the speaker's location and contact details on Google Map.

Each lecture delivered by the speakers is assigned to one or more topics from the set of topics defined by the ACMDSP committee. The problem of categorizing lectures into topics is similar to the problem of categorizing research papers into topics. Hence, for each topic, we have manually associated a set of keywords from the NSERC list of research topics. These keywords are used to create training sets for each topic. Title and abstract information of these research papers along with a lecture topic are used to train the machine learning models, which classify each lecture title and abstract into one or more topics of a predefined topic structure.

This thesis uses three document representations, based on bag of words, bag of concepts and bag of categories. We have used three consensus methods, which include linear regression, class with maximum probability and voting based. Each of these methods is a consensus method in itself and every individual consensus method forms an agreement to predict a topic.

This thesis expanded on the previous classification model based on semantic representations of lecture titles/abstracts that can classify a large set of lectures into topics. Previous work used the topics to construct the training data. However, this thesis used the NSERC keywords to describe the ACMDSP topics and construct the training data. The classifier can predict up to three topics for a single Lecture.


title: HELP-SEEKING BEHAVIOURS OF ADULTS FROM SEXUAL AND GENDER MINORITIES LIVING WITH PSYCHOLOGICAL DISTRESS

contributor:
Department of Psychiatry Research
Master of Science
Matthew Numer
Sherry Stewart
Ingrid Waldron
Zenovia Ursuliak
Amy Bombay
Received
Not Applicable
No

subject:
Mental Health
LGBTQ+ Health
Depression
Anxiety
Psychological Distress
Help-seeking
TCAM
Alternative Medicine
Complementary Medicine
Sexual minorities--Health and hygiene

abstract: Increasing research has highlighted certain health disparities experienced by lesbian, gay, bisexual, transgender, queer and other gender/sexual minorities (LGBTQ+) peoples, particularly in relation to poorer mental health outcomes (Keuroghlia, Ard, & Makadon 2017; Kidd et al., 2016). Using a mixed-methods design, this study explored help-seeking with various mainstream, traditional, and/or complementary medicine practitioners among LGBTQ+ and heterosexual, cisgender adults living with psychological distress in the Halifax Regional Municipality (HRM). An online survey revealed that psychological distress, experiences of mental health discrimination, and help-seeking behaviours differed based on gender identity, sexual orientation, and mental health diagnosis. A focus group revealed unique experiences of LGBTQ+ patients that influence treatment adherence and outcomes, and emphasized how discrimination, patient-practitioner rapport, and insurance coverage were primary factors affecting help-seeking. These findings indicate that the health care system in the HRM needs to be improved to provide more accessible mental health services to LGBTQ+ patients.


title: Investigating Maintenance Of The Yeast 2-Micron Family Of Plasmids

subject:
Plasmid partitioning
budding yeast
partitioning proteins
partitioning locus
chromosome segregation

abstract:
The 2µm plasmid of Saccharomyces cerevisiae is the best-studied member of a family of multi-copy plasmids found only in Saccharomycetaceae budding yeast. All members of the family are small circular double-stranded DNAs that share structural and functional similarities but lack significant nucleotide sequence identity. These plasmids use yeast replication and segregation machineries for their own maintenance but do not seem to benefit or pose a detriment to the host. For the 2µm plasmid, association of the plasmid-encoded Rep1 and Rep2 proteins with the cis-acting STB partitioning locus has been shown to be required for equal partitioning of plasmid copies at host cell division. Other members of the family, the 2µm-like plasmids, remain mainly uncharacterized. The goal of this research was to experimentally analyze 2µm-like plasmids pSR1 and pSB3 from Zygosaccharomyces rouxii and pKW1 from Lachancea waltii to gain a better understanding of the components and features required for plasmid maintenance, as well as to investigate the contribution of the 2µm Rep proteins to the plasmid partitioning mechanism.
Plasmid inheritance assays were used to identify the 2µm-like pSB3 plasmid partitioning locus (PAR) and show that the pSB3 plasmid could efficiently partition in a heterologous S. cerevisiae host. Despite this, the partitioning loci of pSR1, pSB3 and pKW1 could not functionally substitute for 2µm STB and increase the inheritance of a 2µm-based plasmid in S. cerevisiae. These results suggest that partitioning locus recognition by the plasmid proteins is plasmid-specific and sequence differences between the loci might determine the specificity of the cis-acting sequence. Consistent with this, the pSB3 partitioning proteins Rep1 and C recognized the pSB3 PAR sequence in vivo but could not associate with the 2µm STB DNA sequence.
The pSR1 and pSB3 partitioning proteins associated with their partners in vivo, with pSB3 Rep1 and C interacting through their amino-terminal regions, as previously observed for 2µm Rep1 and Rep2. Additionally, the C-terminal domain of pSB3 Rep1 was required for the efficient association of the pSB3 C protein with the pSB3 PAR locus and plasmid gene promoters. Taken together, these results suggest that the mechanism of plasmid partitioning between pSB3 and 2µm plasmids is conserved as well as the transcriptional regulation of plasmid genes by the partitioning proteins.
Artificial tethering of proteins to a non-partitioning plasmid was used to characterize a novel Rep1-independent role of 2µm Rep2 in 2µm plasmid partitioning and to show that motifs that enable this function can now be assessed by mutational substitutions. Furthermore, the C-terminal 65 amino acids of 2µm Rep2, required for this Rep1-independent function, could be functionally substituted by the corresponding C-terminal region of the pKW1 C partitioning protein.
This research represents the first experimental analysis of partitioning proteins encoded by other members of the 2µm-like family of plasmids and has provided insight into a contribution of 2µm Rep2 to plasmid partitioning that is independent of its interactions with the Rep1 partitioning protein. Additionally, results obtained in this research suggest that all members of the family function in the same way which may reflect their evolution from a common ancestor. Furthermore, molecular tools developed in this study will now allow further investigation of the partitioning mechanism by which the 2µm-like plasmid family is stably maintained.


title: AN EXPLORATION OF ALCOHOL CONSUMPTION EXPECTATIONS AMONG STUDENTS ENTERING UNIVERSITY RESIDENCES: A HEALTH PROMOTION APPROACH TO DEVELOPING SOLUTIONS

contributor:
School of Health & Human Performance
Master of Arts
Dr. Lori Weeks
Dr. Lynne Robinson
Dr. Lois Jackson
Dr. Heather Neyedli
Dr. Jacquie Gahagan
Received
Not Applicable
Not Applicable

subject: Alcohol Expectations Students Residence

abstract:
Introduction: University students living in residence consume alcohol in a harmful way. Often this behaviour starts immediately. Little is known about the expectations of students moving into residence.

Methods: Exploratory mixed methods. All data was collected using an anonymous online questionnaire. Quantitative data was analyzed using a Kendall’s-tau calculation of correlation. Qualitative data was analyzed using qualitative description.

Results: All quantitative variables were found to be correlated. Student’s expectations are based on what they know about the past experiences of others as well as their own history with alcohol consumption. Predominantly students are choosing to drink in residence to feel connected to others and cope with the demands of student life.

Discussion: Students have a complex relationship with alcohol. Health promotion is uniquely positioned to address this phenomenon.

Conclusion: Higher education institutions like Dalhousie University should use the principles of Health Promotion as a guide to create meaningful change.


title: “THE ACADIAN OF OUR FANCY” : Clothing, community, and identity among the Neutral French, c. 1670-1750

contributor:
Interdisciplinary PhD Programme
Doctor of Philosophy
Mary Beaudry
Lynne Robinson
Catherine Cottreau-Robins
Marc Lavoie
Lynn Sorge
Jerry Bannister
Not Applicable
Not Applicable
Not Applicable

subject:
Acadia
Material culture
Dress studies
Textile history
Atlantic history
Historical archaeology
Beaubassin
Belleisle
Melanson
Louisbourg

abstract: “The Acadian of our Fancy” explores Acadian textile culture from French colonists’ establishment outside of Port Royal to the deportation of 1755. It addresses questions of change and identity: did the Acadians maintain a dress style consistent with their provincial French origins, or did they develop a new vernacular? How did developments in material culture shape Acadian identity? This thesis argues that the larger Acadian settlements began to develop a localized clothing system — based on their distinct social, environmental, geographical, and economic contexts — without losing connection to the fashions of the Ancien Régime. It applies an interdisciplinary framework that draws upon fields of dress studies, history, and archaeology. It also interrogates material entanglement theory as an effective framework for dealing with the lack of surviving garments from the period. To this end, it offers an analysis of Acadian dress culture in the settlements of Belleisle, Melanson, and Beaubassin, and among Acadians living in the urban environment of Fortress Louisbourg. It analyzes 709 artifacts related to dress and textile production and use, 284 inventory entries, and 19 textual descriptions of Acadian dress and dress-related items. It demonstrates that climate and geography had a significant influence on dress change, as did new local resources such as sealskin and tisavoyanne dyes. Acadian communities were not only developing a distinctive language of dress but differentiating among themselves as well. Those differences emerged based on location and environment, trade patterns and levels of contact with surrounding groups. Settlers continued to maintain their cultural and economic ties outside of Acadia, engaging in trade and social exchange that influenced their habits. Most distant from centres of colonial authority, Beaubassin’s status as a trading hub made the region a locus for the evolution of Acadian fashion. Other settlements used dress and accessories that reflected their proximity to the urban elite, resulting in wardrobes more typical of European fashion. Some elements of what would later develop into Acadian folk dress were present prior to the deportation, including the striped weave commonly associated with later Acadian dress, but these elements were integrated in a vernacular grounded in contemporary style.


title: THE ASSOCIATION BETWEEN SELF-RATED HEALTH AND KEY INDICATORS OF HEALTH IN AN OLDER POPULATION: ANALYSIS OF THE CANADIAN LONGITUDINAL STUDY ON AGING

subject:
Self-Rated Health
Aging
Population Health
CLSA
Health Measurements

abstract:
Self-sated health (SRH) is a global indicator of health which reflects a person’s integrated perception of their own health. To obtain an in depth understanding of SRH, this study examined the association between SRH and key indicators of health in particular measures of physical health, psycho-social, health behaviours and clinical health measure.
This population-based sample was comprised of 51,338 men and women aged 45-85 years from the Canadian Longitudinal Study on Aging (CLSA) and included both tracking and comprehensive cohorts. Ordinal logistic regression models assessed odds ratios and confidence intervals and estimated the association between SRH and key objective and subjective indicators of health.
Fully adjusted model revealed that SRH has statistically significant association with numerous health measures in particular measures of physical, cognition, depression and clinical health measures. SRH has the ability not only to reflect physical, psycho-social and health behaviours but also it accounts for clinical health measures.


title: The distribution of copepods in the Shubenacadie River Estuary relative to the diet of larval striped bass (Morone saxatilis)

contributor:
Faculty of Agriculture
Master of Science
Dr. Gordon Price
Dr. Janine Gray
Dr. Stephanie Collins
Dr. James Duston
Received
Not Applicable
Not Applicable

subject:
Striped bass
Estuary
Copepods
Shubenacadie
Match-Mismatch Hypothesis

abstract: The distribution of both copepods and larval striped bass were quantified in the upper estuary (25-40 river kilometer) from May to August 2016 and 2017. Examining the distributions of larvae and potential prey relative to time of year and salinity was important to test the Match-Mismatch Hypothesis. The abundance of first-feeding stage striped bass (6mm total length, TL) peaked at 463/m3 May 29-June 4th, 2016, and 595/m3 June 12-18th, 2017, in 1-10ppt salinity. Larvae were broadly distributed from tidal freshwater to 25.0ppt. The larvae were ‘gape limited’ and failed to feed until late June due to the absence of prey of suitable size. Once feeding commenced, the initial prey was a small adult harpacticoid (0.8-1.0mm TL) of the family Ectinosomatidae, genera possibly Halectinosoma or Pseudobradya based on DNA and morphological analysis. Daily mean abundance of this copepod was 209-281/m3 in salinities of 1.1-2.0ppt in June 2017. Once larvae started growing, larger prey included copepods (Coullana canadensis and Pseudodiaptomus pelagicus) and mesoplankton (mysids and amphipods).


title: Four Architectural Design Methods for the Active Perceiver: A Study of Phenomenology and Place in the Architectural World

contributor:
School of Architecture
Master of Architecture
Maria Arquero de Alarcon
Steve Parcell
Sarah Bonnemaison
Catherine Venart
Not Applicable
Not Applicable
Not Applicable

subject:
Halifax
Phenomenology
Architecture
Place
Photography
Grand Parade

abstract: Dissecting the work of phenomenologist Maurice Merleau-Ponty, this thesis aims to generate a collection of design methods founded in theories of perception and place. In an effort to comprehend the intangible aspects of phenomenology, photography is employed as a metaphor and as a research tool supporting the development of the final design. The methods are then tested on a set of architectures that build upon existing elements of the Grand Parade in Halifax, Nova Scotia, developing connections to their histories, existing events and imagined potentials.


title: EXPLORING CATALYSIS IN THE MANDELATE RACEMASE SUBGROUP OF THE ENOLASE SUPERFAMILY: SUBTLE DIFFERENCES IN THE CATALYTIC MACHINERY

contributor: Department of Biochemistry & Molecular Biology

subject: Enzymology

abstract: The mandelate racemase (MR) subgroup of the enolase superfamily of enzymes (ENS) is mechanistically diverse but structurally similar. This work focused on conserved active site residues in subgroup members MR and L-fuconate dehydratase (FucD). The impact of a Tyr 137-Lys 164-Lys 166 triad on the pKa of Lys 166 of MR was investigated. A Y137F mutation increased the pKa of both Lys 166 and His 297 by 1-1.4 pKa units. FucD was assayed for inhibition with tartronate and 3-hydroxypyruvate (3-HP), which bind the conserved Brønsted acid-base catalysts of MR. Tartronate was found to be a weak linear mixed-type inhibitor of FucD (Ki = 8.37 ± 0.72 mM, α = 7.53 ± 1.16) and 3-HP irreversibly inactivated FucD (kinact = 1.49 ± 0.0058 x 10-4 s-1, KI = 7.94 ± 0.24 mM, kinact/KI = 0.0187 ± 0.0007 M-1s-1). Lastly, Trp 101 on the interdigitating loop of FucD was found to be critical for catalysis.


title: INFERRING ATMOSPHERIC AEROSOL PROPERTIES FROM SATELLITE OBSERVATIONS AND A GLOBAL CHEMICAL TRANSPORT MODEL

subject:
Atmospheric Science
Satellite data
GEOS-Chem
aerosols

abstract:
Atmospheric aerosols have significant impacts on climate and human health. However, the exact magnitude of the climate and health effects of aerosols remains highly uncertain, due to the large variability in aerosol physical and chemical properties. The use of satellite observations of aerosol properties in conjunction with global chemical transport models can improve our understanding of the interactions of aerosols with radiation and their impacts on health.
Using GEOS-Chem coupled with a radiative transfer model, we develop a global simulation of the Ultraviolet Aerosol Index (UVAI) to interpret satellite UVAI observations. This simulation allows us to constrain the absorption by brown carbon (BrC) aerosol produced from biomass burning. Inclusion of absorption by BrC in GEOS-Chem reduces tropospheric hydroxyl radical by reducing the frequency of the photolysis of ozone.  We calculate the direct radiative effect (DRE) of BrC, and find that absorbing BrC changes the global annual mean all-sky top of atmosphere DRE by +0.03 W m−2 and all-sky surface DRE by −0.08 W m−2.
We interpret trends in satellite observed UVAI values using our UVAI simulation for 2005-2015 to improve our understanding of trends in global aerosol composition. Trends in absorption by dust dominate the simulated UVAI trends over desert regions. The UVAI simulation underestimates positive UVAI trends over Central Asia, possibly due to an increasing dust source from the desiccating Aral Sea that may not yet be represented by models. Trends in absorption by BrC  dominate UVAI trends over biomass burning regions. Trends in scattering by secondary inorganic aerosol dominate UVAI trends over the eastern United States and eastern India.
We estimate surface PM2.5 concentrations using information from satellites, simulation, and ground monitors for the years 2000-2017. These combined PM2.5 estimates benefit from recent updates to satellite AOD sources, developments in chemical transport models, and expanded ground monitor measurements. We find improved agreement between our PM2.5 estimates and ground monitors versus prior work.  We use our improved estimates to calculate trends in PM2.5 both globally and regionally in order to understand the exposures of the global population.


title: The Living Yard: Re-Making the Public Square for Community Identity

contributor:
School of Architecture
Master of Architecture
Anne Cormier
Steve Parcell
Talbot Sweetapple
Niall Savage
Not Applicable
Not Applicable
Yes

subject:
Architecture
Community Design
Adaptive Reuse
Urban Design
Halifax
Nova Scotia
Affordable Housing
Self Built

abstract:
How do we design and develop in urban areas where we are witnessing the social impacts of gentrification? Through adaptive reuse, this thesis will investigate issues of the gentrification process in the North End of Halifax, Nova Scotia. Looking for inclusive development models to mitigate issues of identity loss and community retention in changing neighbourhoods, and provide new ways to interact with the public square, a living yard.
These ideas will be considered through an adaptive reuse project of Saint Patrick’s Alexandra Junior High School in Halifax’s North End. Through study of the systems of oppression within Halifax and meetings with representatives of the different communities directly implicated in the future of this site, this thesis intends to understand the needs of these stakeholders and provide a programmatic response that enables inclusive growth for all.


title: A COMPARISON OF VIABILITY AND VITALITY TESTING METHODS AFTER BENCH SCALE UV- AND HEAT-TREATMENT OF THE DIATOM THALASSIOSIRA WEISSFLOGII

contributor:
Department of Civil Engineering
Master of Applied Science
Dr.  Hany El Naggar
Dr. Margaret Walsh
Dr. Hugh MacIntyre
Dr. Graham Gagnon
Not Applicable
Not Applicable
Not Applicable

subject:
Ultraviolet treatment
Phytoplankton
Ballast water treatment

abstract: Thalassiosira weissflogii, a marine diatom, was inactivated using two bench-scale treatment methods: ultraviolet radiation (UV-C) and a water bath (50°C). After treatment with either UV-C or heat, and a 24-hour dark incubation, cultures were analyzed using a range of monitoring methods to assess viability and vitality: serial dilution culture most probable number (SDC-MPN), cellular ATP concentration, vital stains, and chlorophyll fluorescence. T. weissflogii viable cell concentration was reduced by 3-log after 6 minutes of heat exposure or 148 mJ/cm2 of UV-C radiation. UV-C treatment is far more energy efficient, using less than 1% of the equivalent input energy required for heat treatment. Viability, as determined through a growth assay, is compared against the other monitoring methods. Vitality testing was demonstrated to produce false positive results, especially for the UV-C treated cells.


title: Optimization Framework for Natural Gas Storage Assets Subject to Price Uncertainty

contributor:
Department of Industrial Engineering
Master of Applied Science
Dr. Lei Liu
Dr. Ahmed Saif
Dr. Ahmed Saif
Dr. Uday Venkatadri
Dr. Claver Diallo
Not Applicable
Not Applicable
Not Applicable

subject:
Optimization
Operations Research
Industrial Engineering

abstract: Natural gas offers a clean and efficient fuel-burning method of power generation and heating. North America, specifically, features a sprawling network of natural gas pipelines and storage facilities that bring natural gas (NG) from source to customer. Like many commodities (oil, electricity, etc.), the price of NG is subject to uncertainty. Natural gas storage assets can allow marketing companies to make money by injecting or withdrawing gas at opportune moments. Even simple contracts; however, involve large numbers of decisions and constraints that must be considered. Furthermore, because of the financial nature of storage decisions, it is desirable to measure or include risk in the decision-making process. This work presents optimization framework that serves as a decision support tool for natural gas storage assets. Mixed-integer-programming models are presented for two types of storage decisions: forward and cash. Model framework includes constraints that consider the impact of asset inventory on injection and withdrawal rates. Including said constraints is found to be essential in determining feasible injection and withdrawal decisions when assets are subject to inventory ratcheting. For both cash and forward decisions, Stochastic, Robust and Distributionally Robust Optimization alternatives are presented to account for risk. Parameterization of the risk-management alternatives allows for a user to obtain tactical plans for storage assets while considering varying levels of risk tolerance and averseness.


title: In-depth Understanding of the Stability Response of a Novel 3D Fiber-Metal Laminate under Axial Impact Loading

contributor:
Department of Mechanical Engineering
Doctor of Philosophy
Dr. Mehdi Hojjati
Dr. Dominic Groulx
Dr. Darrel Doman
Dr. Dmitry Garagash
Dr. Farid Taheri
Not Applicable
Yes
Yes

subject:
Composite material
3D Fiber metal laminate
Impact buckling
Finite element modeling
Bonding enhancement

abstract:
Environmental concerns have developed significant challenges for various industries, including the automotive industry. In fact, the industry has been challenged to halve vehicles’ fuel consumption by 2025. Considering the fact that engine efficiency has been approaching a plateau, the other effective means for reaching the set target is believed to be achieved by reducing the weight of various components of vehicles. It should be noted that, unfortunately, vehicles collisions occur frequently; consequently, vehicles must be designed in such a way to assure the maximum safety of the occupants, thereby generating an additional constraint to the weight-reduction approach.
To address the latter design constraint, the automotive industry has been conducting an extensive series of research over the recent decades to explore the utilization of different light-weight metallic alloys and fiber-reinforced plastic composites (FRPs). However, relatively recently, it was proved that one could achieve optimal results by taking advantage of the marriage of the positive attributes of two distinctly different classes of materials (i.e., metallic alloys (preferably, the light-weight alloys), and FRPs). The aforementioned material combination is referred to as a fiber-metal laminate (FML) and was first used in aviation field (e.g., Airbus A380). The resulting hybrid combination enables one to take advantage of the unique properties of each constituent. Following this path, our research group recently developed a new class of three-dimensional FML that offers exemplary specific strength and stiffness, superior energy absorption capacity, and excellent damping properties compared to the traditional materials used throughout the industry, in a cost-effective manner. It takes advantage of a recently marketed 3D-knitted fiberglass fabric, infilled with a resilient foam, and sandwiched between thin sheets of light-weight magnesium alloy.
The primary application target of this 3D fiber-metal laminate (3D-FML) has been transport vehicles’ body components, which are subjected to various loadings, including impacts. The superior energy absorption capacity of this new FML under a lateral impact, in comparison to traditional fiber-reinforced composite materials, has already been demonstrated by our research group. However, the targeted components may also encounter in-plane compressive loading applied at various loading rates, which could lead to the instability of the structural system.
The overall aim of this work is to provide a deeper insight into the response of slender structural components made with the 3D-FML, when subjected to in-plane compressive load applied at various strain rates (particularly, to low-velocity impact loading). The task will be done by conducting a series of systematic and comprehensive experimental and numerical investigations. The finite element method is utilized to carry out the parametric studies, identifying and ranking the material properties that would most affect the response of the system. In addition, the interface bond strength (which will be shown to be the Achilles’ heel of the introduced hybrid system), is optimized, thereby improving the overall fabrication process of the FML in an efficient and cost-effective manner. In addition, the feasibility of graphene nanoparticles (GNPs) as a means of enhancing the interface bond strength of the system was explored. The results revealed that the lack of chemical bond between the GNP-reinforced resin and the magnesium skins of the hybrid material system significantly limited the potential influence of the GNPs.
It is also well-known that composites’ performance is strongly affected by the existence of delamination(s) within them. Therefore, the effect of initial delamination on the performance of the material system is also systematically investigated.
Finally, a set of simple semi-empirical equations is developed by which practicing engineers could quickly evaluate the buckling and maximum load bearing capacities of the 3D-FML subjected to in-plane static and low-velocity impact loading states.


title: A Novel Model of Elevated Mitochondrial Cholesterol and The  Consequences for Mitochondrial Function

subject:
Mitochondrial cholesterol
Mitochondrial dysfunction
VDAC
Neurodegeneration
Cancer

abstract: Increased mitochondrial cholesterol may induce mitochondrial dysfunction and play a role in the progression of neurodegenerative disease and cancer. The voltage-dependent anion channel of the outer mitochondrial membrane has been proposed to participate in cholesterol-related mitochondrial dysfunction through altered associations with proteins involved in metabolism and apoptosis. Current models for studying the effects of mitochondrial cholesterol are disease-based models, blurring the line between true mitochondrial cholesterol effects and other disease effects. Here we present a novel model of increased mitochondrial cholesterol, MitoSTARD4, in which mitochondrial cholesterol content and import to the inner mitochondrial membrane are increased. Cells with increased mitochondrial cholesterol produce more lactate. I explored the mitochondrial associations of voltage-dependent anion channel interacting proteins in cells with elevated mitochondrial cholesterol; BCL-XL, GRP75, PINK1 and PARKIN all have increased mitochondrial presence. The MitoSTARD4 model supports previous findings in disease models that increased mitochondrial cholesterol content induces alterations to mitochondrial function.


title: The Role of Blood-Brain Barrier Pathology in Post-Traumatic Epilepsy and its Co-Morbidities

contributor:
Department of Medical Neuroscience
Master of Science
Dr. Sultan Darvesh
Dr. Kazue Semba
Dr. William Baldridge
Dr. Alon Friedman
Received
Not Applicable
Not Applicable

subject:
Post-Traumatic Epilepsy
Blood-Brain Barrier Pathology

abstract:
Traumatic brain injury (TBI) is becoming a global epidemic with an up-to-date figure putting its toll at 69 million people affected worldwide. In Canada, TBI accounts for 150,000 annual emergency room visits and about half-a-million people are living with a TBI-related disability. The more debilitating forms of TBI have also been associated with a higher risk of about 10-40% for developing post-traumatic epilepsy (PTE) as well as long-term cognitive impairments, neurodegenerative and neuropsychiatric diseases. There are currently no effective therapeutics for the prevention of PTE and associated co-morbidities. Accumulating evidence indicates that blood-brain barrier dysfunction (BBBD) is common following TBI and has a role in epileptogenesis. The goal of the present study was to test whether imaging BBB dysfunction following TBI can be used to predict the development of PTE and its associate co-morbidities.
Methods: We used a weight drop model of moderate traumatic brain injury in young adult rats. Rats were assessed for primary injury using a neurological score at baseline, 24, 48 hours and 1-week after injury. The magnitude of BBBD was assessed using a contrast-enhanced magnetic resonance imaging (CE-MRI) at 48 hours and 1-month time points. PTE was assessed using telemetric continuous electrographic recordings between 2-6 months after injury. Cognitive impairment was assessed using the Morris water maze test at 1 month after the trauma.
Results: CE-MRI confirmed BBBD 48hrs after injury in contrast to healthy controls. To this end, 6 rats (26%) developed PTE at 6-months post injury. Epileptic rats showed abnormal pattern of brain activity with increased occurrence of slow frequency events, termed “paroxysmal slow wave events” (PSWEs). Morris water maze confirmed a reduction in learning skills in animals after injury. The extent of BBBD at 48 hours was inversely related to performance at the Morris water maze, but not with the development of epilepsy at 6-months.
Conclusion: Post-traumatic epilepsy is fairly common following moderate traumatic brain injury. PSWEs may reflect an underlying neuronal hypersynchronous activity and may offer a novel non-invasive biomarker for neural injury and epileptogenesis. BBBD imaging may serve as a predicting biomarker for the development of cognitive impairment.


title: KAPOSIN B-MEDIATED MECHANORESPONSIVE SIGNALLING CONTROLS PROCESSING BODY DISASSEMBLY

contributor:
Department of Microbiology & Immunology
Master of Science
Dr. Neale Ridgway
Dr. Brent Johnston
Dr. Barbara Karten
Dr. James Fawcett
Dr. Jennifer Corcoran
Dr. Roy Duncan
Not Applicable
Not Applicable
Not Applicable

subject:
Virology
Actin
Processing Bodies
Mechanoresponsive
Stress Fibres
Kaposi's sarcoma-associated herpesvirus

abstract: Kaposin B (KapB) is a viral protein that induces the formation of actin stress fibres (SFs) and promotes stabilization of inflammatory and angiogenic mRNAs by disassembling processing bodies (PBs). PBs are ribonucleoprotein granules that control mRNA post-transcriptional expression. The canonical cytoskeletal regulatory GTPase, RhoA, is required for both KapB-mediated phenotypes – the formation of SFs and PB disassembly. I investigated signalling controlling SF formation, bundling and contractility in the mechanism of KapB-induced PB disassembly. Knockdown of RhoA-effectors known to coordinate SF formation restored PBs in KapB-expressing cells. Inhibition of actomyosin contractility also restored PBs, while inducing contraction disassembled PBs. Since SFs mediate mechanotransduction, YAP was investigated and shown to mediate PB disassembly in the context of KapB and other mechanical forces, including shear stress. Using a viral protein, my research identified and dissected a novel mechanoresponsive pathway controlling PB turnover and the concomitant stability of inflammatory and angiogenic transcripts.


title: Characterization of the Cannabis Terpene Myrcene in Joint Pain and Inflammation in a Rat Model of Rheumatoid Arthritis

contributor:
Department of Pharmacology
Master of Science
Dr. Morgan Langille
Dr. Christian Lehmann
Dr. Denis Dupre
Dr. Jason McDougall
Received
Not Applicable
Not Applicable

subject: arthritis pain terpenes cannabinoids

abstract:
Rheumatoid arthritis is a progressive inflammatory condition resulting in joint damage and debilitating pain. Current treatments present with variable efficacy and negative side effects, leaving pain management a priority. The endocannabinoid system has been targeted to relieve both inflammation and pain in disease conditions. Specifically, the non-euphoric cannabis terpene myrcene offers analgesic actions in acute pain models, and anti-inflammatory potential in vitro. We investigated the effect of both acute and chronic administration of myrcene alone, and in combination with cannabidiol, on pain and inflammation in the Freund’s complete adjuvant (FCA) rat model of rheumatoid arthritis. The involvement of the endocannabinoid system was also explored. Evoked and spontaneous pain behaviour were analyzed using von Frey hair algesiometry, dynamic weight bearing, and locomotor activity. Inflammatory parameters assessed were oedema, leukocyte trafficking, blood flow to the injured area, cytokine levels, and joint histopathology.
Our study found that both acute and chronic administration of myrcene attenuated evoked mechanical allodynia, but did not improve FCA-induced weight bearing deficits, and did not alter locomotor activity. Acute administration of myrcene reduced leukocyte trafficking. Chronic administration reduced leukocyte trafficking and blood flow, yet had no effect on cytokine levels or disease progression. These anti-inflammatory effects were mediated via the endocannabinoid system; however, endocannabinoid-dependent analgesia was not confirmed.
Excluding blood flow, the analgesic and anti-inflammatory effects of myrcene were comparable to diclofenac. The combination of myrcene with a suboptimal dose of cannabidiol did not enhance any of the above parameters.
Compared to other analgesic treatments, myrcene may be a safer therapeutic to use in conjunction with disease-modifying treatments to adequately manage pain and inflammation in rheumatoid arthritis.


title: Canada’s Policy Response to  Refugee Young People from  War-Affected Regions: The Case of Halifax, Nova Scotia

contributor:
Interdisciplinary PhD Programme
Doctor of Philosophy
Dr. Stacey Wilson-Forsberg
Dr. Lynne Robinson
Dr. Theresa Ulicki
Dr. Shelly Whitman
Dr. Linda Liebenberg
Dr. David Black
Received
Not Applicable
Not Applicable

subject: youth refugee policy resilience

abstract:
Displacement around the world has surpassed anything seen in modern history. In 2018, the UNHCR reported that 70.8 million people have been displaced worldwide, with just over half of them being under the age of 18. Of the total number of displaced persons, 41.3 million have been internally displaced in their home country, 25.9 million are refugees, and 3.5 million are asylum seekers. The UNHCR also reports that over half of displaced people are under the age of 18.  While we know there are major challenges in supporting refugee youth from war-affected regions in Canada as a whole, we need to know more about how smaller urban centres such as Halifax can and do respond to refugee youth.
To address this issue, this dissertation presents a policy analysis of Canada’s response to refugee young people, and then provides a case study of services in the Halifax area to better understand where resources for this population exist in this city, and the strengths and limitations of these resources. Even though over half of refugees settling in Nova Scotia are young people, they have been largely a footnote in federal resettlement policies. The purpose of this research is to understand the intersections and between policy and the services that exist and make recommendations for how service providers can be better supported in their work with refugee young people.
The main question guiding this research is: How are smaller urban centres, like Halifax, prepared to support refugee youth in their resettlement and integration? A social ecological resilience framework was used to identify the resilience resources identified in the systems surrounding refugee young people in Halifax. What is important for effective integration in the community is for supports for newcomers to exist not solely in settlement service organizations, but across public services and sectors throughout the city.
The findings show that Halifax has the capacity to provide better integration support for refugee youth. With more cultural awareness and intentional collaboration, youth serving organizations, as well as broader community services, can become more effective resources for the resilience of these young people.


title: A Look into the Reactivity and Functionality of Pyrroles and Dipyrrins

contributor:
Department of Chemistry
Master of Science
Dr. Peng Zhang
Dr. Norman Schepp
Dr. Alex Speed
Dr. Alison Thompson
Not Applicable
No
No

subject:
Synthetic Chemistry
Pyrroles
Dipyrrins

abstract:
The dipyrrin unit formally consists of a pyrrolic unit and an aza-fulvenium unit. Within this thesis, two projects involving pyrroles and dipyrrins will be discussed.
2-Formyl pyrroles play a critical role in pyrrole chemistry because they act as a precursor to multi-pyrrolic compounds including dipyrrins. Herein a new synthetic route to 2-formyl pyrroles from 2-thionoester pyrroles is explored. 2-Thionoester pyrroles, when treated with Raney nickel in acetone, are reduced to their corresponding 2-formyl pyrroles. Along with the optimization process of this desulfurative reduction, mechanistic studies are discussed.
By arylating the α-, β-, and meso-positions of dipyrrins, we wish to establish a synthetic pathway for each position of arylation. Through pre-functionalization of pyrroles and Suzuki coupling, α-Ph and β-Ph dipyrrins were synthesized. Miyaura borylation of dipyrrins were attempted to explore a new synthetic route to introduce an aryl moiety onto the dipyrrin core.


title: On Models for Detecting Evidence of Molecular Adaptation in Homologous Sequences of Protein Coding Genes

contributor: Department of Mathematics & Statistics - Statistics Division

subject:
molecular evolution
adaptive evolution
codon substitution models
confounding
phenomenological load

abstract: Codon substitution models (CSMs) are commonly fitted to alignments of homologous protein-coding sequences with the objective of determining whether sites in the gene underwent positive selection. Under the standard paradigm such evidence is often assumed to be enough to conclude the gene evolved adaptively. CSMs are commonly validated using simulated alignments. A central theme of this dissertation is use of relatively realistic alignment-generating processes grounded in mutation-selection (MS) theory (Chapter 1). The MS framework permits sites to be evolved each on their own site-specific fitness landscape defined by a vector of fitness coefficients for the twenty amino acids. A novel MS alignment-generating process was used to show that evidence for variation in site-specific rate ratios (a.k.a. heterotachy) with episodic positive selection can be produced by episodic adaptive changes in site-specific fitness coefficients, consistent with the standard paradigm, but also by a second previously unrecognized process that I call non-adaptive shifting balance. This finding undermines sophisticated CSMs specifically designed to infer episodic adaptation by detecting heterotachy with episodic positive selection (Chapter 2). Processes that tend to generate similar patterns in data are said to be confounded. Confounding can lead to a novel statistical pathology that I call phenomenological load. A series of novel CSMs fitted to alignments generated under a version of MS uniquely formulated to mimic real data were used to demonstrate that phenomenological load can lead to false biological conclusions. These analyses were accompanied by a novel method to assess the potential impact of phenomenological load on any given model parameter (Chapter 3). Confounding of adaptive and non-adaptive processes that generate heterotachy can be avoided by abandoning positive selection as an indicator of adaptation and instead using evidence of changes in site-specific amino acid fitnesses. This approach was realized by constructing the phenotype-genotype branch-site model (PG-BSM), a descendant of traditional branch-site models that combines alignment data with a discrete phenotype (i.e., contextual information) under a unified statistical framework. The PG-BSM was validated using extensive simulations and produced plausible results when applied to real data (Chapter 4). This dissertation ends with a discussion of implications of my findings (Chapter 5).


title: A DAILY DIARY EXAMINATION ON THE RELATIONS OF DEPRESSED MOOD AND COPING MOTIVES WITH CANNABIS USE QUANTITY ACROSS THE MENSTRUAL CYCLE: COMPARING CANNABIS USING FEMALES WITH AND WITHOUT PRE-MENSTRUAL DYSPHORIC DISORDER

contributor:
Department of Psychiatry Research
Master of Science
Dr. Jennifer Stamp
Dr. Sherry Stewart
Dr. Philip Tibbo
Dr. Kimberley Good
Dr. Sherry Stewart
Received
Yes
Not Applicable

subject:
Female
Menstrual Cycle
Cannabis
Ovarian Hormone
Progesterone
Self-Medication
Pre-menstrual Dysphoric Disorder
Coping Motives
Depressed Mood

abstract:
Cannabis is one of the most commonly used drugs in Canada. Though limited, research suggests female, versus male, heavy cannabis users have a higher propensity to develop a cannabis use disorder. Recent research suggests that addictive behaviors, like alcohol use, may change, along with mood states and addictive behavior motives, across the menstrual cycle (MC), particularly during the pre-menstrual and menstrual phases. In this thesis, daily diary methodology was used to examine relations between cannabis use, depressed mood, and coping motives in normally-cycling female cannabis users across the MC. We hypothesized that heightened cannabis use would be associated with depressed mood and coping motives pre-menstrually and menstrually. We also hypothesized that females with a provisional pre-menstrual dysphoric disorder (PMDD) diagnosis would experience stronger relations between cannabis use, depressed mood, and coping motives premenstrually and menstrually versus females without PMDD. A sample of 69 normallycycling female cannabis users (Mage = 29.25, SD = 5.66) were recruited and completed
daily assessments on cannabis use quantities, depressed mood, and coping-motivated cannabis use. Results from the primary analyses indicated no relationship between cannabis use and depressed mood or coping-motivated cannabis use across the MC in the overall sample or among those without a PMDD diagnosis (n = 50). However, a provisional PMDD diagnosis (n = 19) appeared to be an individual difference factor affecting cannabis use across the MC, with depressed mood predicting heightened cannabis use menstrually, and coping motives predicting heightened cannabis use premenstrually and menstrually. Additionally, females with PMDD displayed a greater overall cannabis use quantity during the self-monitoring than females without PMDD. These results add to a growing body of literature pointing to the potential importance of female reproductive hormone variations in accounting for addictive behaviors in females. Findings also have important treatment implications for reproductive-aged females with PMDD who misuse cannabis (e.g., beginning a cannabis cessation/reduction attempt during the ovulatory or luteal phases of the menstrual cycle; training in more adaptive skills for managing depressed affect to be employed during the pre-menstrual and menstrual phases).


title: When the Messiah Comes: The Postsecular Messianic in Contemporary Literature

contributor:
Department of English
Doctor of Philosophy
Dr. Lori Branch
Dr. Kathy Cawsey
Dr. Alyda Faber
Dr. Dorota Glowacka
Dr. Alice Brittan
Not Applicable
Not Applicable
Not Applicable

subject:
postsecularism
contemporary literature
messianic
literature

abstract:
Despite proclamations about the death of God and the decline of religious institutions throughout the twentieth century, questions of secularism and religion are currently being re-thought through the lens of postsecularism.  The concept of the postsecular does not imply that religion has been temporally or intellectually superseded as the secularization thesis posited, but instead indicates the necessity of new approaches to thinking about spiritual life in the early twenty-first century. In this dissertation, I consider how literary postsecularism constructs an alternate space – which I frame as the messianic – which challenges the binary erected between secularism and religion.  Though literary postsecularism has become a lively and growing field of late, the messianic remains an under-theorized aspect of this field.  I examine how authors such as Marilynne Robinson, J.M. Coetzee, Marjorie Liu, Gene Luen Yang, Colum McCann, and Mohsin Hamid re-evaluate the role of religion in literary discussion post-9/11.  Following Manav Ratti’s model in thinking of the postsecular as a negotiated term, I argue that these authors respond to urgent contemporary matters such as neoliberalism, colonialism, and migration by reconceiving the messianic as an ethical practice with critical aesthetic dimensions.
 	In the first chapter, I draw on Walter Benjamin’s and Jacques Derrida’s work on weak messianism to argue that the postsecular situates the messianic as a collective instantiation of responsibility, intimacy, and possibility.  In later chapters, I explore the hopeful possibilities that postsecular readings of Robinson, Coetzee, McCann, and Hamid produce, while also highlighting the often-Eurocentric tensions and problems that arise in conceptualizing the postsecular in Yang’s and Liu’s comics.  Motivating my readings is a consideration of how each author invokes a sacramental poetics of the everyday that offers a pluralistic and imaginative vision for living well with others in the twenty-first century.


title: Phosphorylation-dependent Changes in the R-region Interactions Contribute to Regulation of the CFTR Chloride Channel

contributor:
Department of Physiology & Biophysics
Doctor of Philosophy
Dr. Frédéric Becq
Dr. Alexander Quinn
Dr. Alexander Quinn
Dr. David Langelaan
Dr. Xianping Dong
Dr. Valérie Chappe
Not Applicable
Not Applicable
Not Applicable

subject:
CFTR
PKA Phosphorylation
PKC phosphorylation
Regulatory region
Domains interactions

abstract: Cystic Fibrosis Transmembrane Conductance Regulator (CFTR), the defective protein in cystic fibrosis, is an ion channel regulated by PKA and PKC phosphorylation of its regulatory region (R-region) through a mechanism still not completely understood, preventing a full comprehension of the process involved in CFTR activation. To provide novel insights into the CFTR activation mechanism, I analyzed in situ and in vitro interactions of the R-region with other parts of CFTR at different phosphorylation conditions (PKA, PKC, PKA+PKC). For in situ analysis, I used a split-CFTR construct expressing the front half (FH;N-tail/TMD1/NBD1), back half (BH;TMD2/NBD2/C-tail) and the R-region as three separate polypeptides expressed in BHK cells. I found that PKA stimulation increased both FH-R and BH-R interactions and PKC+PKA further increased only FH-R interactions whereas PKC stimulation alone had no effect. Inactivation of PKC consensus site S686 (S686A) significantly reduced basal BH-R interaction and prevented the further enhancing of FH-R interactions by PKC+PKA phosphorylation that was found with the wild-type R-region. The opposite phosphomimetic mutation S686D restored basal BH-R and rescued 80% of FH-R interactions after PKC+PKA stimulation compared to wild-type levels. As the channel function is mainly stimulated by PKA phosphorylation of the R region, and this response is doubled by PKC+PKA phosphorylation, results from this thesis suggest that PKC enhances PKA effect by increasing R-region interactions with the FH. Also, PKC site S686 was found to be crucial for the PKC enhancing effect which appeared to be mediated by a permissive interaction of the R-region with the BH, allowing FH-R interactions to be enhanced by PKC.  Analysis of in vitro interactions of the R-region with six polypeptides corresponding to the N- and C-terminal tails and the four cytoplasmic loops (CLs) of CFTR showed that phosphorylation strongly increased R-region interactions with both N- and C-tails of CFTR. Moreover, PKA and PKC+PKA phosphorylation reduced R-region interactions with CLs 4 and 3, respectively, a mechanism that permits the channel activation by PKA and PKC enhancing effect. All together, these results demonstrate that phosphorylation induces an R-region shift from the cytoplasmic loops to both amino and carboxyl ends of the protein, to activate the channel.


title: Fast K-Means Clustering Via K-D Trees, Sampling, and Parallelism

contributor:
Faculty of Computer Science
Master of Computer Science
Michael McAllister
Vlado Keselj
Evangelos Milios
Norbert Zeh
Not Applicable
Not Applicable
Not Applicable

subject:
K-means
Parallel computing
K-D trees
Clustering

abstract: K-means is a commonly used method for clustering in applications that require fast response time due to its speed. As data becomes large (millions of data points), the classical implementation may not achieve the performance necessary for these applications. By combining the filtering algorithm using k-d trees, aggressive sampling, and parallelism with dynamic load balancing, we implement a version of k-means that outperforms the standard algorithms used for these applications. We find that aggressive sampling at 1% of the dataset combined with the filtering algorithm provides significant speed-up without sacrificing accuracy. Overheads in implementing parallel methods prevent significant speed-up on smaller datasets, especially when the data has already been sampled, but our experiments show that this improves as the dataset grows.