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Exploring new commercial opportunities for Arctic echinoderms: an ecological and nutritional assessment
No full textEchinoderms are distributed throughout the world oceans where they take part in pivotal ecosystem functions. They are also highly valuable resources, traded for their health benefits and cultural importance, especially in Asia. Given their value, harvesting efforts are expanding globally. In the Canadian Arctic, the development of fisheries is being explored around two echinoderm species, the sea cucumber Cucumaria frondosa and green sea urchin, Strongylocentrotus droebachiensis. While both species are currently harvested in eastern Canada, fundamental knowledge, including general ecology and commercial value, of Arctic populations is limited. The present thesis sought to address this knowledge gap. The first study utilized surveys conducted with a portable remotely operated vehicle (ROV) within Qikiqtait (traditional name for Belcher Islands, Nunavut), to assess population metrics and habitat usage in C. frondosa and S. droebachiensis. There was significant inter-site variation. Sea cucumbers were found in higher densities at the deepest sites (33 m) with gravel and rubble substrates and high levels of suspended particulate matter. Sea urchins, conversely, were denser on shallower seabeds (23 m) dominated by red coralline algae. Size distributions showed sea cucumbers predominantly ranged from 6-10 cm in length, while sea urchins were mainly 3-4 cm in test diameter. The number and size of aggregations increased with density in both species. The second study compared the phenotypic characteristics of C. frondosa sampled in Nunavut versus Newfoundland. Despite similar total body weights, Newfoundland sea cucumbers had heavier gonads and body walls, whereas Nunavut individuals displayed unique pigmentation and biochemical profiles. Muscle bands of sea cucumbers sampled in Nunavut had lower protein and lipid contents but higher ω-3 fatty acids, fatty acid unsaturation, proline, vitamin A, carbohydrates, and astaxanthin levels. Together, the two studies provide insights into the Arctic populations of C. frondosa and S. droebachiensis,
helping to assess their commercial potential, while highlighting how the local environment may influence the ecology of these valuable echinoderms. Ultimately, the findings offer baseline information in the face of a rapidly changing Arctic environment, while acting as a foundation for future research related to the management of benthic resources around Qikiqtait.Includes bibliographical reference
The human dimensions of Newfoundland and Labrador's murre hunt: a social-ecological study
No full textA human dimensions approach to wildlife management was used to solicit murre hunter and stakeholder perspectives, attitudes, and recommendations for current Common Murre (Uria aalge) and Thick-billed Murre (Uria lomvia) harvest management practices in the Canadian province of Newfoundland and Labrador (NL). NL is the only jurisdiction that administers a legal, non-Indigenous murre hunt in North America. The overarching goals of this study were formulated to help inform potential changes for upcoming murre hunting seasons. A qualitative approach was utilized by conducting one-on-one interviews designed to collect hunter and stakeholder input on current murre harvest regulations and practices, provincial murre population status, alternative management strategies, the social and cultural significance of the murre hunt, the perceived extent and impact of illegal harvesting, and hunters’ participation in the CWS National Harvest Survey. Results indicated that over-harvesting, lack of enforcement, illegal activity, limited access to population data, species harassment, and lack of community engagement were frequently reported hunter concerns. Interview analyses conclude that hunter input provides valuable local knowledge for resource managers to inform future harvest seasons. However, it also indicated a strong desire for more mechanisms for harvester feedback and input to secure the delivery of apt environmental policies.Includes bibliographical references (pages 63-76
Opportunity recognition as a precursor to the antecedents of entrepreneurial intention within the context of gender and the university environment and support system
No full textThis study analyzes the relationship between opportunity recognition (OR) and the antecedents of entrepreneurial intention (EI) while exploring gender differences in these relationships within the context of university environment and support System (ESS). A dual-stage approach was used to analyze partial least squares structural equation modelling (PLS-SEM) and structural causal models (SCM). The PLS-SEM revealed significant direct effects of ESS on OR. It also showed a direct effect of OR on the precursors of intention: attitude toward behaviour, subjective social norms, and perceived behavioural control. Finally, the regression revealed gender moderation in the relationship between ESS and OR. Surprisingly, gender did not moderate between OR and the antecedents of entrepreneurship. The SCM further confirmed the direct causal effect of OR on the antecedents of entrepreneurship. More importantly, the current findings suggest that OR could be positioned as a precursor to antecedents of EI. This study was carried out among 389 university students in Atlantic Canada. No study to date has explicitly considered the effect of OR the antecedents of entrepreneurship. Additionally, to the author's knowledge, it is the first study in entrepreneurship to combine PLS-SEM with structural models using extracted latent variable scores.Includes bibliographical references (pages 70-102
Investigating whether a lack of preparedness contributes to teacher burnout among early career teachers
No full textBurnout has long been a recognized issue for teachers, and numerous studies have examined the factors contributing to burnout and its consequences for the teaching profession. This report presents the results of a study involving 132 current permanent or substitute teachers teaching during the 2021-2022 and 2022-2023 school years. The research question asked whether a lack of preparedness contributed to burnout in early career teachers and to identify factors that likely contribute to compassion fatigue. Teachers completed an online survey addressing factors contributing to compassion fatigue, self-rated their competencies, and identified perceived stressors in the teaching profession. The study, conducted via Qualtrics, received ethics approval from the Interdisciplinary Committee on Ethics in Human Research (ICEHR). Additionally, six teachers working during the 2021-2022 school year participated in phone interviews.
An analysis of the qualitative data revealed several factors contributing to compassion fatigue and burnout, as reported by teachers during the 2021-2022 school year. Key contributing factors included unrealistic expectations (18.5%, n=28), lack of support (10.6%, n=16), time management and parental involvement (i.e. both with 7.3%, n=11). Another key contributing factor was the need for more counsellors (6.6%, n=10) and smaller class sizes (6.6%, n=10). All phone interview participants (n=6) confirmed they had experienced burnout and had witnessed colleagues experience burnout. The themes that best represented early career teachers’ responses were unrealistic
expectations (33.33%, n=2/6), extreme workload (33.33%, n=2/6), time management (33.33%, n=2/6) and lack of support (33.33%, n=2/6).
An analysis of the quantitative data showed that the primary stressors identified by participants were managing work-life balance (7.23/9, n=64), managing health and energy (6.89/9, n=64) and time management (6.21/9, n=63). Participants rated their competency levels in Part B as “excellent” in maintaining a professional disposition but only “good” in relation to practical classroom competencies, government expectations, technology and teaching theory and practice.
Study findings, particularly qualitative data, indicate that teachers believe a significant gap exists between teacher training and the challenging classroom realities new teachers face. Educators pointed to a lack of resources and administrative support, which they believe to be the cause of uncertainty and heightened stress. Teachers noted uncertainty about legal rights and how to negotiate the intense emotional and psychological burdens associated with their jobs. They also referred to the need for more effective practicums, mentorship, and practically orientated teacher training as ways to improve teacher preparedness.
The implications of these findings for Memorial University's teacher training program and professional development are discussed. Recommendations include further research into the contributors to teacher burnout, emphasizing practical solutions.Includes bibliographical references (pages 135-150
Understanding how exercise and standard-of-care drugs affect iPSC-derived cardiomyocytes from a male ACM patient
No full textArrhythmogenic Cardiomyopathy (ACM) is a heart disease causing sudden cardiac death and heart failure. There is a large population of ACM patients in Newfoundland and Labrador (NL) with an autosomal dominant mutation in the TMEM43 gene (TMEM43-S358L). The Esseltine lab collected dermal punch biopsies from several NL ACM patients harbouring the TMEM43 mutation and genetically reprogrammed these skin cells into induced pluripotent stem cells (iPSCs). Additionally, we sought to investigate the fibrosis component of the disease using ACM patient dermal fibroblasts. However, IPSCs can differentiate into any cell type in the body, including cardiomyocytes. The two largest factors for severe disease presentation include being male and engaging in exercise. Although it is unknown how exercise exacerbates arrhythmogenicity in ACM, it is postulated to occur through adrenaline stimulation of the β-adrenergic receptor. In fact, β-blockers are standard-of-care treatment for ACM patients. Therefore, we are investigating how male ACM patient-derived iPSC-cardiomyocytes respond to the β-adrenergic receptor modulation. Unstimulated male ACM iPSC-cardiomyocytes demonstrate disturbed contraction frequencies and aberrations in calcium handling compared to unaffected male control iPSC-cardiomyocytes. β-adrenergic modulation did not affect the frequency of contraction for ACM patient iPSC-CMs. Dermal fibroblasts experiments showed fibrotic features for the ACM patient fibroblasts. Future studies will identify personalized treatment strategies for ACM patients, and how the TMEM43-S358L mutation leads to cardiac fibrosis.Includes bibliographical references (pages 82-97
Policies and technologies for a ‘fish out of place’
No full textIn a world where the race to feed a growing population intensifies, the oceans have become the new frontier for food production. Aquaculture, particularly salmon farming, has risen as a beacon of hope, promising to deliver protein-rich food to millions. Yet, beneath the surface of this industry’s success, complex environmental challenges persist—most notably, the escape of farmed salmon, which casts long shadows over wild salmon populations and fragile marine ecosystems.
This thesis evaluates the effectiveness of existing policies and technologies in mitigating the ecological risks associated with farmed salmon escapes. Through a detailed analysis of 14 global salmon production regions, the research assesses the strengths and weaknesses of these policy frameworks, revealing that while regulatory measures have evolved, their effectiveness is often constrained by weak enforcement and the inherent challenges of open-net pen aquaculture. Additionally, the thesis explores the role of triploid (sterile) salmon in addressing the environmental challenge of escapes, with a particular focus on aquaculture production in Newfoundland, Norway, and Tasmania. By situating these findings within the broader context of environmental policy and the global aquaculture industry, the thesis reveals the complexities of aligning production goals with environmental sustainability in food production.Includes bibliographical reference
Guppy gene expression dynamics: effects of sex, reproductive status, feeding, and temperature on reproductive function, methylation, and appetite
No full textIntroduction: This thesis examines the dynamics of gene expression in guppy fish (Poecilia reticulata) under various growth conditions, diets, and temperatures. Understanding the molecular processes underlying methylation, reproduction, and appetite regulation in these fish is the goal of this research. The process by which genetic information is transformed into useful products like proteins is known as gene expression. Guppy reproduction is highly impacted by elements like diet and temperature. This work investigates the effects of these factors on gene expression.
Methodology: Male and female guppies (Poecilia reticulata) were housed in 20L aquariums with filtered water at 25°C under a 12-hour light/dark cycle. Fish were acclimated for a week and fed daily with Fancy Guppy meal. For gene expression analysis, fish were divided into experimental groups: 1) fasting vs. feeding for 14 days, 2) temperature effects (25°C, 32°C, and 18°C). Tissues (brain, liver, intestine) were collected post-mortem for RNA extraction using the GeneJET RNA Purification Kit. Total RNA was reverse transcribed using the SensiFAST cDNA Synthesis Kit. Specific gene expression was analyzed via qPCR, and primer design was based on Poecilia reticulata sequences. Data were analyzed using the 2-ΔΔCt method, normalized to reference genes GAPDH, EF-1α, and β-actin. Statistical analyses included ANOVA and non-parametric tests with a significance level of P<0.05.
Results: A total of 45 guppies were examined, including 33 females and 12 males, with females classified into three reproductive stages. Analysis of brain gene expression showed no significant differences in orexin (OX) or NPY levels between groups, but Kiss2 expression was higher in females with late-stage embryos, while AVP was elevated in males. Intestinal and liver genes expression showed no significant changes. In fasting experiments, females consumed more food than males, with brain orexin in fast male and hepatic dnmt3b expression in fed male being significantly higher. Gnrh3 and npvf expression in fasted male and IT expression in fed female were higher. Temperature experiments revealed that food intake increased at higher temperatures, and npvf and Orexin levels were elevated at 32°C and 18°C in males. However, no significant changes were observed in epigenetic-related genes in response to temperature variations.
Conclusion: This study demonstrates how environmental elements like temperature and diet can have a substantial impact on guppy gene expression and phenotypic adaptation. The results of this study advance our knowledge of the molecular mechanisms underlying living things' flexibility and adaptation to environmental changes and may find use in aquaculture and conservation.Includes bibliographical references (pages 81-98
Tongue root harmony in rural and urban Jordanian Arabic: feature-geometric and optimality-theoretic accounts
No full textThis dissertation examines how the retracted tongue root ([RTR]) feature, borne by emphatic segments, spreads to neighboring segments in two Jordanian dialects: (1) Rural Jordanian Arabic (RJA) and (2) Urban Jordanian Arabic (UJA). This dissertation contributes to a deeper understanding of emphasis directionality and opacity, and the boundaries of emphasis spread (ES). It also investigates whether uvular and coronal emphatics constitute a natural class. Furthermore, it explores how Feature Geometry (FG) and Optimality Theory (OT) treat ES. In RJA, results reveal that coronal and uvular emphatics constitute a natural class. Within the stem and infixed data, [RTR] spreads exhaustively leftward but is blocked from spreading rightward by [-back] phonemes. [RTR] spreads to prefixes that are tautosyllabic with a root consonant. Suffix material links to [RTR] when suffixes are either tautosyllabic with, or immediately adjacent to, an emphatic trigger. However, the rightward spreading of [RTR] is obstructed by blocking segments. In UJA, results reveal that [RTR] spreads to all segments to the left but spreads rightward to first low vowel /a, aa/ and iteratively spreads to laryngeals, pharyngeals, and other low vowels. Also, [RTR] always links to a non-blocking consonant immediately following a coronal emphatic. [-low] segments block rightward ES. The prefixal data shows a distinct pattern of [RTR]-linking, where prefixes link to [RTR] when they are tautosyllabic with a root consonant.
The analysis shows that OT better explains the asymmetrical ES of [RTR] than an FG analysis which uses distinct features to account for directionality. In the FG analysis proposed here, two spreading rules apply: [PH] accounts for leftward ES, whereas (2) [RTR] accounts for rightward ES. However, one drawback of this approach is that the same, indistinguishable, segments can be associated with [PH] or [RTR]. Still, FG, when supplemented with the [PH] rule, offers valuable insight into phonology-morphology interaction. Conversely, FG, when supplemented with the [RTR] rule alone, does not fully explain some suffixal patterns in RJA. In contrast, the proposed OT hierarchy accounts for the asymmetry of ES in both dialects and illustrates the interaction between phonology and morphology in conditioning morphologically complex forms
The prevalence and predictors of aggressive obsessions in obsessive-compulsive disorder: a meta-analytic review
No full textBACKGROUND: Obsessive-compulsive disorder (OCD) is a heterogenous condition often characterized in relation to major symptom dimensions including contamination, symmetry/exactness, religious, aggressive, sexual, hoarding/saving, somatic, and miscellaneous. Aggressive obsessions, defined as intrusive thoughts of (unintentionally or intentionally) harming oneself or others, are experienced as distressing, are commonly misdiagnosed by healthcare providers, and are highly stigmatized. The aims of the current study were to: (a) provide an aggregate estimate of the worldwide prevalence of aggressive obsessions among adults (18+ years) with clinician-diagnosed OCD; and (b) quantify sources of heterogeneity amongst prevalence estimates using moderator analyses. METHOD: A systematic search was conducted using PubMed, PsycINFO, and CINAHL databases. Of the 4218 studies screened, 91 were coded for analysis. Original, prospective studies were included if they assessed clinician diagnosed OCD samples (based on DSM-IV, DSM-5, or ICD-10 criteria), reported the lifetime or current prevalence of obsessive-compulsive symptom dimensions including aggressive obsessions, and included patients 18 years of age or older. Prevalence of aggressive obsessions was extracted, alongside a series of moderators. A logit transformation was applied to the prevalence values, which were then aggregated using a random effects meta-analysis, with moderators explored using meta-regression. Log-risk ratios were also examined where data were available. RESULTS: Lifetime and current (past-week) prevalence rates were estimated to be 71.9%, CI95% [64.4, 78.3], and 53.8%, CI95% [47.4, 60.1], respectively, and reflected substantial heterogeneity. Moderator analyses revealed higher past week prevalence of aggressive obsessions across samples with a greater mean age, longer mean illness duration, and lower mean age of OCD onset; while samples from the Asia Pacific region showed lower estimates. Finally, risk ratio analyses revealed that individuals with: a) early vs. adult OCD onset; and b) suicidal ideation vs. not, were at 1.13 times,
CI95% [1.03, 1.24], and 1.98 times, CI95% [1.47, 2.66] greater risk of experiencing aggressive obsessions, respectively. CONCLUSIONS: Results support the need for early identification and increased monitoring among individuals experiencing aggressive obsessions
Navigating the urban-rural divide in EV adoption: equity challenges and policy implications of mandatory zero-emission vehicle transitions in British Columbia
No full textThe transition to electric vehicles (EVs) is crucial for reducing greenhouse gas emissions globally. As Canada commits to decarbonizing its transportation sector, aiming for 100% zero-emission vehicle (ZEV) sales in new light-duty vehicles by 2035 (Transport Canada, 2024), British Columbia's ZEV Act establishes even more ambitious targets of 90% by 2030 (Ministry of Energy, Mines and Low Carbon Innovation, 2024). While critical for climate change mitigation, this study investigates how the distribution and accessibility of electric vehicles are uneven; they are not uniformly available across different communities. By examining the transportation equity implications of EV adoption disparities between rural and urban areas in British Columbia (Metro Vancouver and the Kootenay region as comparative cases), this research analyzes multiple dimensions of geographical disparities in transportation electrification. Through descriptive analysis of publicly available data from government databases, non-profit & industry reports, we compare the factors that shape EV adoption in rural and urban areas and examine how universal ZEV mandates affect residents differently based on their geographic location. The findings reveal a nearly ninefold difference in adoption rates between Metro Vancouver and the Kootenay region (3.30% versus 0.38%). The regions also differ with regard to key factors that influence EV adoption, including limited charging infrastructure, higher financial burdens for rural households, severely limited public transit options, and reduced exposure & awareness to EV technology, impacting rural people's adoption decisions. These results demonstrate that British Columbia's ZEV mandate, without targeted interventions to address geographical inequities, risks creating a ‘green divide’ that reinforces rather than alleviates existing inequities and these disparities reflect inequitable policy choices rather than inevitable outcomes. This study contributes to transportation equity and sustainable energy policy discourse by providing empirical evidence of how sustainable mobility transitions affect different communities. It demonstrates that achieving equitable outcomes in transportation electrification requires moving beyond one-size-fits-all approaches to develop rural-specific interventions, including geographically differentiated infrastructure investment, rural-calibrated economic incentives, and targeted information campaigns. The implications extend beyond British Columbia to similar regions globally, underscoring the importance of considering geographical diversity in crafting effective and equitable transportation electrification policies