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Quantifying the impact of environmental contamination using Drosophila melanogaster across biological sex and genetic background
No full textThe world is a stressful space. There is a strikingly large knowledge gap in the genetics of stress responses. Stressors are present in nature, such as to exposures to extreme pH, temperatures, and toxicants. We used the response of Drosophila melanogaster to environmental nickel (Ni) as a model to better understand stress, where stress is defined by dysregulation homeostasis. To broadly characterize stress responses, we assayed both males and females of three different types of genetic backgrounds – isogenic, isogenic constructed heterozygotes, and genetically diverse wild-caught lines – of D. melanogaster across a series of phenotypes that range in specificity. We measured Ni response broadly using mortality and more specifically using metabolites. Not surprisingly, Ni negatively impacted every phenotype. Lifespan, feeding, and total lipids were reduced when exposed to Ni. Surprisingly, the Ni effects were substantially different between the sexes, types of genetic backgrounds, and lines. For example, the differences between males and females themselves varied substantially across lines. Similarly, the types of genetic backgrounds and lines differed in response, highlighting genetic complexities. In sum, my results clearly demonstrate that to truly understand the biology of a system, both sexes and multiple lines must be used
Side effects of GLP-1-based weight loss therapies
No full textGlucagon-like peptide-1 receptor agonist (GLP-1) has arisen as a groundbreaking pharmacological weight management treatment, demonstrating remarkable effectiveness in reducing body weight in individuals who are considered obese with or without type 2 diabetes mellitus. Despite their clinical advantages, GLP-1 RAs (GLP-1 Receptor Agonists) are frequently associated with gastrointestinal (GI) symptoms, including nausea, vomiting, diarrhea, constipation, and dyspepsia. These adverse effects are usually dose-dependent and occur frequently during the initial stage of therapy, often dropping with continued use. However, in some instances, these symptoms may persist or worsen, leading to discontinuation. Additional concerns include frequent yet significant complications such as pancreatitis and gastroparesis. Emerging reports highlight the necessity of evaluating pre-existing GI conditions, implementing gradual dose titration, providing patient education, and dietary modification to improve tolerability. A comprehensive strategy that involves diligent monitoring, tailored dose modifications, and supportive management of symptoms. This critical review examines the role of GLP-1 RAs in weight-loss therapy, addressing pharmacology and pharmacodynamics, and strategies to minimize adverse events while improving patient outcomes
Exploring media stories and narratives of elite athlete motherhood : a meta-synthesis and narrative inquiry of self-portrayals on Instagram
No full textMotherhood and athletes’ career goals have long intersected in elite sport as a site to illuminate persistent issues of gender equity, professional sport cultures and inclusion. As athletes continue with sport careers once starting their families, the study of motherhood and high-performance sport has garnered attention from qualitative researchers. These research findings show that the negotiation of a sport career for athlete mothers is complicated due to an inequitable sport system and societal assumptions that women must place children before a sport career. Athlete mothers are also having successful sport careers and performances and being praised, yet they are doing so despite less support, or in the face of shifting support that has a way to go. Researchers have explored the media as a cultural site conveying meanings via narratives/discourses to learn more about these tensions in socio-cultural context. Motherhood was initially studied in mainstream media forms (e.g., news, magazine, sport). Findings showed that motherhood and sport were often portrayed as incompatible with an elite sport career due to media portrayals placing childcare and motherhood as all-consuming or sportswomen being less capable as mothers. Scholars exploring contemporary media representations of motherhood and sport have highlighted nuanced media portrayals of elite athlete mothers that include resistance, conformity, and empowerment. The central purpose of this dissertation was to further explore these intersections in the media to advance understanding of motherhood and sport meanings, the psycho-social implications, and provide future research and applied recommendations. Two studies were conducted using relativist narrative inquiry as a theoretical framework and methodology to achieve these aims. The first study was a meta-synthesis of published qualitative media study findings on elite sport and motherhood. The purpose was to explore the published media studies that included media sources, sports, motherhood status, and nationality to synthesize descriptive trends from the study findings, identify new narrative themes synthesized from findings, and make research recommendations. A total of 15 published studies were gathered spanning from 17 years (i.e., 2006-2022). The descriptive theme findings included: 1) (in)compatibility between athlete and mother identities, 2) motherhood as an individual responsibility, and 3) controlling the body. The new narrative themes were: 1) entitlement to impose and 2) maternal activism and new ethic of care. The second study built off the first study by focusing on the role of sense of community in athlete mothers’ careers. To answer the research questions, visual and textual posts in one social media space (i.e., Instagram) were explored and theorized as small stories (i.e., fragmented and co-created daily happenings) to investigate sense of community meanings for four successful Canadian elite curler mothers (i.e., Rachel Homan, Kaitlyn Lawes, Jocelyn Peterman, and Sarah Wilkes). A total of 217 posts related to sport, career, family and community were collected and analyzed using a big and small story approach to identify a big story narrative of growth and stability amidst belongingness. The big story narrative was shaped by three small stories highlighting sense of community meanings: (re)integration of children and mothers, striving for excellence, and expanding communities and careers. Collectively, both studies in this dissertation point to more acceptance of motherhood in sport through a range of nuanced big and small stories circulated in a range of media sources (e.g., mainstream, social media), through progressive narratives. The significance of the main findings of the two studies are outlined in the conclusions, along with highlighting the value of narrative inquiry as a theory and methodology to learn more about the mediation of motherhood and sport. Practical suggestions for sport practitioners and media professionals are also put forward.Laurentian University, Dr. Kerry R. McGannon
Gallium and rare-earth elements: a critical review of their roles, recovery, and sustainability challenges
No full textGallium (Ga) and the rare-earth elements neodymium (Nd) and dysprosium (Dy) are important materials for many of today’s electronic products, renewable energy systems, and advanced materials. However, processes for separating these elements from ores and reprocessing them often involve a lot of energy and corrosive chemicals with significant environmental impacts. Therefore, in the current review, we will focus on the geological occurrence of Ga and REEs, the extraction process, and sustainability issues, including the chemistry of the lixiviants used in hydrometallurgical operations. Gallium is usually extracted as a by-product to the mining of aluminum and zinc, while Nd and Dy are extracted directly from the minerals bastnasite and monazite, often using acidic or alkaline leaching. Recently, new low impact techniques such as deep eutectic solvents, ionic-liquids, organic acids and biological lixiviants, for safer and more selective recovery have been introduced, mostly from waste materials such as red mud, fly ash and electronic scrap. Overall the development of closed-loop recovery systems and environmentally-friendly lixiviants are crucial to limit the environmental impact and ensure the long-term availability. The new extraction technologies involving both chemical and biological processes will play a critical role in ensuring the global supply of Ga, Nd and Dy in a growing low-carbon economy
FRA1 (FOSL1) suppresses spontaneous and radiation-induced transformation through transcriptional control of transformation-associated genes, remodeling of activator protein-1 composition, and regulation of cell cycle checkpoints
No full textFRA1 (FOSL1), a member of the Activator Protein-1 (AP-1) transcription factor complex, is implicated in various aspects of cancer biology. However, its role in early carcinogenesis, particularly during radiation-induced transformation, remains poorly understood. This thesis investigates the functional role of FRA1 in neoplastic transformation using the CGL1 human hybrid cell line, which is derived from the fusion of normal human fibroblasts and the cervical cancer HeLa cell line. This genetically stable model is well-suited for studying both spontaneous and radiation-induced transformation. Using CRISPR-based tools, we generated CGL1 cells with either FRA1 overexpression or knockout and assessed their phenotypic and molecular characteristics. FRA1 overexpression induced broad transcriptional changes, including modulation of genes involved in extracellular matrix organization, cell adhesion, and transcriptional regulation. AP-1 subunit composition was also altered, with increased c-JUN and decreased c-FOS and FOSL2 expression, suggesting that FRA1 reprograms the AP-1 complex toward a less transformation-permissive state. Moreover, FRA1 overexpressing cells exhibited reduced adhesion to fibronectin and collagen and showed modest changes in cell cycle dynamics. Functionally, FRA1 overexpression significantly suppressed both basal and radiation-induced neoplastic transformation, whereas FRA1 knockout dramatically increased transformation frequency, indicating a protective role in early tumorigenesis. These transformation effects were not attributable to differences in DNA double-strand break repair, as γH2AX foci resolution post-irradiation was comparable between lines. FRA1 knockout cells exhibited defective G2/M checkpoint activation following radiation, suggesting impaired cell cycle control. To further assess FRA1’s regulatory influence, we evaluated gene expression following serum stimulation. FRA1 overexpression blunted the induction of cFOS and cJUN, while knockout enhanced their expression, revealing that FRA1 modulates early transcriptional responses to mitogenic signaling. RNA sequencing also revealed reciprocal expression of transformation-associated genes across FRA1 knockout, control, and overexpression cell lines. Together, these findings establish FRA1 as a context-dependent tumor suppressor that limits neoplastic transformation through regulation of AP-1 composition, cell cycle checkpoint control, and early transcriptional responses to growth stimuli
Essential wellness architecture: integrating traditional craftsmanship for accessible and inclusive resort design
No full textThe exclusivity of modern wellness spaces has often limited access and cultural relevance, creating a gap in inclusive and restorative design. This thesis envisions a wellness resort along the coastline of Diani, Mombasa, in Kenya that integrates traditional Kenyan craftsmanship with biophilic and contemplative design principles. Drawing inspiration from the Swahili, Maasai, Kikuyu, and Mijikenda communities, it proposes spaces where well-being becomes a shared and inclusive experience, accessible to all. Inspired by Kenyan vernacular architecture, the resort design weaves local materials, cultural motifs, and natural elements into spaces that offers deep connections with nature and community. The approach balances overall well-being with the preservation of cultural identity and environmental integrity. This thesis highlights the need for wellness spaces to move away from exclusivity and embrace inclusivity and cultural authenticity. By blending global wellness concepts with local traditions, the proposed resort offers a thoughtful and sustainable model that supports communities, preserves heritage, and creates spaces for everyone to feel connected and restored
Making in the forest
No full textThis thesis explores making, dwelling, and material knowledge through active engagement with the natural environment. A remote forested site in northern Ontario serves as the setting for an immersive study in which only locally available materials and a limited set of hand tools are used to make essential objects, furniture, and architecture. The process begins with a deep understanding of the site and the available resources. Through iterative making studies, various methods of making are explored, allowing the inherent properties of each material to guide design and fabrication. As the studies progress, they culminate in the design and construction of a dwelling, shaped not by conventional architectural methods but by the transformative knowledge gained through hands-on engagement with the environment and materials. This thesis examines the intersection of making and place, revealing how meaningful design can emerge from an intimate relationship between maker, material, and site
Form follows culture: decolonizing Nigerian dwellings through neo-vernacular design
No full textTraditional Nigerian architecture celebrates impermanence, the cyclic nature of life and architectural spirituality. As African creation myths tell us, “Earth makes man, and everything man makes is bound to the Earth because man was formed from clay”. The trans-Atlantic slave trade, colonization and globalization reshaped the design of contemporary homes, blending styles from Europe and Brazil while displacing the use of local materials. These shifts were driven further by modernist design philosophies such as “ornament is crime,” “less is more,” and “form follows function” (Van der Rohe, Loos, Sullivan), which posed several issues as they displaced traditional markers and stripped homes of their cultural characteristics. This thesis proposes restoring culturally relevant homes made from locally sourced biogenic materials pertinent to the current culture. It will achieve this through neo-vernacular critiques, material collage studies, artifact craft explorations, and an iterative process of thinking through model making. It will redefine dwellings as materially diverse homes that can be adapted for multigenerational households and evolve with the culture of Nigeria
PMMA-rGO nanocomposite: synthesis techniques and applications
No full textThis review explores the growing interest in poly (methyl methacrylate) (PMMA) reinforced with reduced graphene oxide (rGO), a nanocomposite that brings together the best of both materials— PMMA’s transparency and ease of processing with rGO’s remarkable strength, conductivity, and thermal stability. This review highlights various synthesis methods, including in situ polymerization, solution blending, and melt mixing, each offering different advantages depending on the intended application. By incorporating even small amounts of rGO, significant improvements in PMMA’s mechanical and thermal properties, along with the added benefit of tunable electrical conductivity have been observed. These enhancements make the composite a strong candidate for use in flexible electronics, optoelectronic devices, biomedical implants, and protective coatings. The review also discusses the challenges that come with ensuring uniform dispersion of rGO, achieving strong interfacial bonding, and addressing environmental or health concerns associated with nanomaterials. Despite these hurdles, the findings suggest that with continued innovation in synthesis techniques and a better understanding of structure–property relationships, PMMA-rGO nanocomposites hold great promise for next-generation materials. This review concludes by identifying key areas where further research is needed, particularly in scaling up production and evaluating long-term performance in real-world application
Development of scattering correction and UV spectral simulation routines to facilitate investigations on the inhibitory metal site in anthrax lethal factor via tyrosine modification
No full textAnthrax lethal factor (LF) is a zinc-dependent metalloendopeptidase and critical protein component of the anthrax toxin. Previous studies have shown that LF possesses an inhibitory metal binding site which is involved in accelerating metal exchange reactions via an associative mechanism. The current study sought to employ chemical modification strategies in combination with UV-Vis spectroscopy to assess whether a tyrosine residue (Tyr728) near the active site of LF is involved in binding the inhibitory metal ion and in participating in metal exchange. Tyr residues in LF were successfully modified with N-acetylimidazole, however, complications arose in the course of their quantification. For instance, the emergence of variable light scattering complicated the spectrophotometric analysis of the protein samples. To address this, an Excel-based tool was developed that allows for the correction of protein spectra, taking into account both Rayleigh and Mie scattering contributions. Furthermore, the degree of Tyr modification varied drastically (from 5 to 13 modified Tyr residues) for samples prepared under identical experimental conditions when protein concentrations were calculated via a single-wavelength approach. Hence, a second Excel- based routine was designed with the view of calculating more accurate protein concentrations by determining the molar absorption coefficients at each wavelength between 250 and 350 nm. This was achieved by simulating protein spectra based on the abundance and pseudo-Voigt profiles of their amino acid constituents. By implementing this multi-wavelength fitting approach, a better estimate of the number of modified Tyr residues was obtained. Together, the tools produced in this work facilitate the accurate determination of protein concentrations not just for LF, but for proteins in general