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Syllable structure and phonotactics of SiWU
No full textThis study investigates the syllable structure of Siwu and its language-specific rules on syllabification in an attempt to contribute to efforts to document minority languages. In a multilingual setting dominated by a few major languages like Ghana, it is expected that languages spoken by minority groups will face endangerment if their data is not preserved through research. Siwu and other Ghana-Togo Mountain languages are such a group of languages in a subregion dominated by a major lingua franca, Ewe. This study begins with a review of existing works on the Siwu syllable as well as a study of available literature on four other GTM languages in order to determine the scope of the study and to enable a comparative study of these languages. The main focus of the study involves using data from the FCBH Global Bible (2008) to identify all possible syllable types that constitute Siwu’s inventory, examine the sub-constituents of the Siwu syllable, and analyse permissible and non-permissible sequences in Siwu complex onsets. One of my findings is that although some closed syllables are in the language, the majority of Siwu’s syllables are without the coda. Syllables with codas are mostly restricted to ideophones or loan/coined words. Regarding clusters, I find that there is an unequal preference for one of the two segments that occupy the C2 position of Siwu clusters. [r] is more freely distributed than [l]. I provide an analysis of restrictions on onset clusters that makes reference to both sonority and place features within the framework of feature geometry. The comparative study of syllable structure in Siwu and four other GTM languages also reveals that GTM languages have more similarities than differences in their syllable constitution. This study is significant because it is the first to provide a detailed description and analysis of the Siwu syllable.Includes bibliographical references (pages 82-85
Decoding DNA methylation: insights into age-related diseases and transcription factor dynamics
No full textThis thesis investigates the role of DNA methylation in age-related diseases by improving patient classification and exploring transcription factor interactions in the context of methylation. We developed an enhanced k-means clustering algorithm integrated with an expectation-maximization (EM) framework to filter irrelevant CpG sites and reduce noise in patient classification. The algorithm’s performance is benchmarked against traditional k-means clustering to assess its efficacy in stratifying patients and gain meaningful insights. Our method improved patient stratification based on survival outcomes by applying to Kidney Renal Papillary Cell Carcinoma (KIRP) data. It revealed hypermethylated profiles resembling the CpG Island Methylator Phenotype (CIMP), which is associated with poor prognosis. Clinical features better represent the population, and tumour stages are more realistically linked to survival outcomes after grouping using the EM k-means algorithm. An analysis of the Fraction Genome Altered (FGA) and mutation rates suggests that post-cancer development survival rates appear more closely tied to large-scale genomic instabilities induced by aberrant methylation than point mutations. Gene Ontology (GO) and KEGG pathway analyses identified critical pathways in cell adhesion, signal transduction, and BMP signalling influencing tumour behaviour and metastasis. With slight modifications, the EM k-means algorithm was used to predict patient survival based on the methylation patterns. Although there was a large difference between the training and testing populations due to sampling variability, the results were promising, indicating a potential as a diagnostic method for treatment plans.
Extending our approach to Alzheimer's disease (AD), we uncovered genes associated with differentially methylated regions (GADMR) in AD patients not identifiable through traditional Braak staging or simple k-means clustering. The algorithm classified patients into
pseudo-intermediate and pseudo-advanced groups, with significant overlaps in known AD-associated genes and pathways. An age analysis demonstrated that machine learning-classified patients exhibited increased chronological and genetic ages (DNA methylation aberrations) correlated with AD progression risk.
Furthermore, we explored the molecular interplay between transcription factors Ying-Yang 1 (YY1) and TATA-Binding Factor 1 (TAF1). Employing TFregulomeR for motif distribution, genomic location, and Gene Ontology (GO) analysis on the YY1-TAF1 pair, we investigated methylation changes by comparing three scenarios: both TFs present together, and each TF alone by excluding the partner's peaks. From 152 conditions showing significant methylation variations, we focused on the YY1-TAF1 pair in GM12878, H1-hESC, and SK-N-SH cell lines. We found that TAF1 will not co-bind to YY1 when the YY1 binding motif is methylated at the third residue (cytosine or guanine) or when methylation is impossible due to the third residue not supporting it. Although the motif for co-binding peaks is cell-specific, stronger cytosine conservation at the third residue is observed where YY1-TAF1 co-binding occurs. Additionally, TAF1 binding to YY1 depends on an unmethylated state at this site. Our GO analysis reveals that the co-binding of YY1 and TAF1 expands the set of GO terms compared to YY1 alone, indicating a synergistic effect in regulating cellular processes. The extent of YY1-TAF1 co-binding at promoter-TSS sites varies by cell type, being more extensive in cells capable of differentiation. Specifically, co-binding in GM12878 cells correlates with functions related to protein synthesis and RNA processing, while in H1-hESC and SK-N-SH cells, it associates with a broader range of enrichments. Conversely, TAF1 alone shows the opposite pattern, suggesting that cellular needs and differentiation potential influence binding patterns.
In conclusion, this thesis presents a novel computational framework for improving patient classification based on DNA methylation patterns. It sheds light on the molecular mechanisms of transcription factors in the context of methylation specificity. The enhanced EM k-means algorithm demonstrates potential as a diagnostic tool for personalized treatment plans, while the insights into YY1 and TAF1 interactions contribute to understanding gene regulation in disease progression. These findings have significant implications for developing targeted therapies and highlight the importance of methylation dynamics in age-related disease mechanisms.Includes bibliographical references (pages 188-195
Eco-synthesis, application and enhanced water-retention properties of cellulosic hydrogels derived from waste papermill sludge as soil amendments
No full textPoor water retention in acidic soils and prolonged droughts cause major crop losses each year. In boreal ecosystems this poses a challenge for growing food locally, adding to nutrient insecurity. Hydrogels derived from waste biomass offer a sustainable solution by improving water retention without relying on virgin, petroleum or renewable biomass-based resources, contributing to a circular bioconomy. In this study hydrogel-composites were synthesized (i) from cellulose recovered from waste papermill sludge using energy-efficient protocols, (ii) by crosslinking recovered cellulose with citric acid (iii) followed by incorporating various amounts of biochar (BC) as a biocompatible filler. Four hydrogel composites containing BC compositions of 0 g (CH), 0.5 g (BH0.5), 1 g (BH1.0) and 1.5 g (BH1.5) were synthesized and characterized by Fourier Transform Infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and swelling studies (study 1). The effects of 1% and 2% (w/w) of cellulose hydrogel (CH) and biochar-incorporated hydrogel (BH) on sandy loam and silty loam soil were evaluated using water retention characteristics and drought resistance (study 2). The energy-efficient extraction with microwave and ultrasonication recovered cellulose in a 81.5% yield with 93.8% purity. The hydrogel composites showed enhanced water retention in the order BH1.0 > CH > BH0.5 > BH1.5. The application of hydrogels significantly (p<0.05) increased field capacity (FC) in both soils. In sandy loam soil, 2% of CH and BH increased the plant available water (PAW) by 313% and 405%, respectively. In drought-simulated pot experiments, tomato plants treated with 2% CH and BH remained fresh for up to 17 days without water, compared to 5 days for untreated soil. Waste papermill sludge cellulose-derived hydrogels exhibited significant potential as agricultural amendments, enhancing water retention and mitigating crop water stress, contributing to United Nations Sustainable Development Goal 12 (Sustainable Consumption and Production).Includes bibliographical reference
A dyadic exploration into the romantic relationship experiences of Canadians with histories of childhood adversity
No full textAdverse childhood experiences (ACEs) are linked to long-term relational and sexual challenges, yet research rarely explores how individuals uniquely appraise these events or how ACEs affects couples. This thesis had two aims: (1) to describe how traumatic the ten commonly measured ACEs are perceived to be, and (2) to test how perceived partner responsiveness (PPR)—feeling understood and cared for by one’s partner—and event centrality—the degree to which a traumatic event is central to one’s identity—relate to sexual arousal and inhibition for couples (and compared differing dyadic ACEs configurations). Participants were 202 Canadian couples (404 individuals). Aim 1 showed variation in trauma appraisals: women rated parental mental illness as more traumatic, childfree participants viewed emotional and physical neglect as more traumatic, and emotional abuse was reported as the most traumatic, on average. In Aim 2, I compared mixed-adversity couples (one partner had ACEs) and dual-adversity couples (both had ACEs). In mixed-adversity couples, individuals with ACEs experienced greater sexual arousal when they felt supported by their partner (PPR); and greater event centrality was linked to both higher arousal and inhibition. In dual-adversity couples, PPR was linked to greater arousal in one’s romantic partner, and greater event centrality was associated with one’s own higher inhibition and their partner’s higher arousal. These findings underscore the need to study couples’ adversity through a dyadic lens—without dyadic data, critical information is lost related to the effects of the partner. Additionally, findings highlight the value of trauma-informed, couple-based approaches to sexual wellbeing and support more nuanced clinical care for couples with ACEs histories
Economic evaluation of a specialized model of care versus usual care for patients with venous thromboembolism: a systematic review and cost-effectiveness analysis
No full textVenous thromboembolism (VTE) is the third most common cause of cardiovascular related
mortality and is responsible for considerable morbidity. Specialized thrombosis and
anticoagulation care models have shown potential to improve patient outcomes and minimize
overall anticoagulation-related healthcare resource utilization. However, there is limited
evidence on the cost-effectiveness of utilizing a specialized care model versus usual care for
patients with VTE.
This thesis seeks to accomplish two main objectives: first, to conduct a systematic review to
understand the economic implications of specialized models of care for patients with VTE
compared to usual care and second, to conduct a cost-effectiveness analysis of a comprehensive
specialized thrombosis and anticoagulation care model versus usual care for patients with newly
diagnosed VTE in Newfoundland and Labrador (NL)’s largest health region.
In the systematic review, existing economic evaluation studies that compared a specialized care
model against usual care for patients with VTE were evaluated. The included studies were
narratively summarized according to specialized care model type, patient population and
economic evaluation type. We assessed the quality of the included studies and found that the
majority of studies were low-quality economic evaluation studies (> 75%). Additionally, the
review highlighted the lack of studies evaluating a comprehensive care model, and that existing
evidence is based on less contemporary therapies, such as warfarin.
In the cost effectiveness analysis, we compared a comprehensive specialized thrombosis and
anticoagulation management care model (the Thrombosis Service) versus usual care for patients
with newly diagnosed VTE from the healthcare and societal perspective. Effectiveness was
measured in quality-adjusted life-years (QALY). The comprehensive specialized thrombosis and
anticoagulation management care model was found to be the dominant strategy over usual care
with a 93% probability to be cost-effective across various willingness-to-pay threshold.
Conclusion: The results of the systematic review and the cost-effectiveness study indicate that
specialized care models are associated with better clinical and economic outcomes compared to
usual care. These results are of significant importance for clinicians and policymakers tasked
with optimizing care and ensuring appropriate resource allocation to reduce inefficiencies for a
sustainable care pathway for patients with VTE
Photocatalytic removal of pollutants from water using graphitic carbon nitride-based photocatalysts
No full textThis thesis comprises of two main sections. The first part discusses the degradation of nitenpyram using g-C₃N₄ nanosheets and the second part converse the dual functional photocatalysis which involves the simultaneous reduction of Chromium (VI) and oxidation of nitenpyram from water using g-C₃N₄/WO₃ heterojunction. Firstly, the g-C₃N₄ nanosheets were prepared by two step calcination process of melamine in muffled furnace. The characterization results of the prepared nanosheets showed enhanced visible light harvesting ability, narrow band gap and increased surface area compared with the bulk g-C₃N₄ increasing the overall efficiency of the photocatalyst. The nanosheets were utilized as a photocatalyst under visible light to degrade nitenpyram from water. All these experiments were carried out in a batch reactor with a light source for visible light photocatalytic reactions. The results show that it can degrade 99% of the nitenpyram with an initial concentration of 10 ppm at pH 9.0 and catalyst dosage of 1.0 g/L. Further analysis indicates the successful degradation of nitenpyram into its metabolites CPMF, and CPF.
Secondly the nanosheets were combined with metal oxide WO₃ to form a heterojunction which can be used as a dual process for reduction of chromium (VI) and degradation of nitenpyram (NTP). Characterization results show that it has narrower band gap, suitable valance and conduction bands positions, reduced recombination rate of electron-hole pairs which increases its photocatalytic ability for the redox reaction. The experimental outcomes display that it can efficiently reduce chromium (VI) and degrade nitenpyram under visible light. For the dual process at pH 3.0, catalyst dosage of 1.0g/L and initial concentration of 20 ppm the chromium (VI) reduced 88.75% and nitenpyram (NTP) degraded 91.6%. The performance of the heterojunction is compared with the nanosheets and WO3 which shows a considerable increase in removal of pollutants from environment. The band positions of g-C₃N₄ and WO₃, as determined from UV-
DRS, indicate the formation of a Type II heterojunction between the two semiconductors. This configuration significantly enhances the separation of photogenerated electrons and holes, thereby improving the reduction efficiency of chromium (VI) and the degradation efficiency of nitenpyram (NTP).Includes bibliographical reference
Herding cats: a novel pursuit-evasion game
No full textIn the game of Cat Herding on a graph, players alternate turns, with one player (the
herder) omnipresently deleting edges, while the other player (the cat) begins on a vertex
of the graph, and on each turn will move along any path to a new vertex. Eventually
(for finite graphs), the cat is isolated on a single vertex; and the cat�s objective is
to delay this event, while the herder tries to hasten it. In an optimally played (finite)
game, the number of edge deletions the herder made to isolate the cat is the cat number
of the graph, denoted cat(G).
We investigate this graph parameter and graph dynamic from many different angles.
We find the cat numbers of graphs from some common graph families. Some graphs
we view asymptotically (trees, planar graphs), some we find efficiently-computable al-
gorithms to compute the cat number (spiders), and some we solve with explicit closed
forms (paths, cycles, stars, wheels, and complete graphs). We also look at the extremal
instances of the game, characterizing the graphs of low cat numbers (cat(G) ? 3), and
briefly introduce an infinite variant of the game, allowing varying levels at which the
cat can win. From this, we provide a classification of those graphs where the cat or
herder can win
Advancing Arctic marine monitoring through optical technologies and collaborative partnerships
No full textPublishe
An application of polynomial optimization to the study of Hookean solids
No full textA Hookean solid is described by a so-called elasticity tensor, which is a fourth-order
tensor with certain index symmetries that yield, in general, 21 independent components.
However, a Hookean solid can also exhibit material symmetries. For example,
an isotropic solid is described by an elasticity tensor that is invariant under all rotations
of the 3D space and, as a consequence, has only two independent components.
Material symmetries give insight into the mechanical properties of the solid and facilitate
mathematical modelling. Therefore, it is desirable to approximate a given
general elasticity tensor (for example, measured experimentally) by one that belongs
to a chosen symmetry class. In this paper, we compare two di erent formulations of
the problem of nding the closest element in the symmetry class as a polynomial optimization
problem. We apply the polynomial optimization techniques due to Lasserre
to speci c elasticity tensors, utilizing the implementation of Lasserre's method in
MATLAB through the Gloptipoly 3 toolbox
Unassisted homebirths in Afghanistan: a qualitative exploration of underlying reasons
No full textUnassisted homebirths pose significant maternal health risks in Afghanistan, where nearly one-third of births occur at home without skilled birth attendants. Data from 2020 showed the maternal mortality ratio is 620 per 100,000 live births, due to pregnancy and childbirth complications. This thesis explored what factors contribute to unassisted homebirths in Afghanistan from the perspectives of Afghan women and community members. Guided by the social-ecological model, this qualitative case study examined four levels of influence: intrapersonal, interpersonal, community, and institutional. Data was collected through in-depth interviews with Afghan women who had experienced unassisted homebirths and focus group discussions with male and female community members, providing insights into the familial, cultural, and systemic factors influencing choices for birthplace and birth care.
The data indicated that most interview participants had limited knowledge of pregnancy and delivery care, partly due to their lack of access to a reliable source of health information, reinforcing a preference for unassisted homebirth. Patriarchal gender norms like women’s extensive involvement in domestic or agricultural roles, restricted mobility, and limited financial autonomy, along with family dynamics—particularly the influence of elder women, especially mothers-in-law, and male relatives—further constrained women’s ability to seek skilled birth attendance. Cultural beliefs and traditions, including a preference for family-centred childbirth at home, and concerns about modesty also contributed to this preference for unassisted homebirth. Inadequate access to skilled birth attendants—due to distance, financial barriers, lack of transportation, disrespectful care, and perception of poor-quality care—contributed to the perpetuation of unassisted homebirths