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Investigating childhood health in the Central Zagros Mountains during the Chalcolithic: a visual assessment of subadult human remains from Seh Gabi
(2026) Woodley, Claire; Varney, Tamara; Merrett, Deborah; Kaiser, Tim; Waters-Rist, Andrea
This thesis explores the relationship between subsistence strategies in a marginal environment and how it can impact human health. It includes a comparison of all the types of metabolic bone disease (MBD) and their associated lesions and how this informs different possible diagnoses. The residents of the Chalcolithic site of Seh Gabi, Iran (about 6850 to 5100 cal BP) lived in a marginal environment which, when coupled with the intensification of agricultural practices and the use of animal husbandry, could have left the population susceptible to the type of stressors associated with both vitamin C (VCD) and D deficiencies (VDD). This thesis was designed to determine whether the subadult population at Seh Gabi, represented by 32 individuals, experienced VCD and VDD throughout its period of occupancy. The radiographs and excavated skeletal remains of these individuals were macroscopically assessed for any morphology beyond the range of normal. Probable and possible diagnoses of VCD and VDD were made based on the number of diagnostic and suggestive lesions that individuals demonstrated. Probable VCD was evident in 10.7% of the subadult population; all these probable scurvy cases occurred in individuals less than six months old. While there were no probable cases of VDD, two individuals had a possible comorbid case of rickets and scurvy but there was insufficient skeletal evidence to make a probable diagnosis. Extrapolations of maternal health were made based on these subadult health findings given that those under the age of six months were still likely being breastfed. The environmental context and subsistence strategy used by this population, along with these diagnoses, suggest that vitamin C deficiency was likely experienced by this population.
Exploring the workplace experiences of Indigenous workers regarding cultural connectedness and mental health outcomes in Northwestern Ontario
(2026) Bunting, Jazanne; Kristman, Vicki; Levkoe, Charles
Indigenous peoples in Canada face significant disparities in mental health outcomes, which is a challenge that extends into the workplace. Indigenous workers often face a range of workplace factors that contribute to negative mental health outcomes, including discrimination, racism, historical trauma, a lack of cultural safety, and lateral violence. The primary objective of this study was to explore the workplace experiences of Indigenous workers regarding cultural connectedness and mental health outcomes in Northwestern Ontario. The current state of the literature around Indigenous workplace mental health demonstrates a lack of knowledge and understanding of how Indigenous workers experience the workplace, for which this study aimed to contribute to. This study conducted 24 semi-structured interviews with Indigenous-identifying participants working in the Northwestern Ontario region, which were then analyzed using thematic analysis. Findings revealed key knowledge related to cultural connectedness, mental health, and workplace experiences. The results highlight community recognition as an emergent workplace factor for Indigenous workers, which is not included in Canada’s National Standard for Psychological Health and Safety in the Workplace, suggesting that there are workplace factors that are unique to Indigenous workers. This demonstrates the interconnectedness of mental health and cultural connectedness with the workplace. These findings can be used by workplace health and safety representatives to develop and implement policy that is aimed at improving Indigenous worker mental health.
Navigating uneven terrain: An autoethnographic reflection on a White Treaty person's journey to relational responsibilities
(2026) Stewart, Marianne E.; Moeller, Helle; Galway, Lindsay; Martinez, Juan Sanchez
This autoethnographic study explores my relationship with Land and the Anishinaabeg as a White Treaty person spending time on FWFN Traditional Territory. It examines how White Treaty people experience these relationships and how they shape our responsibilities toward Treaties and planetary health. Spending time with Anemki Wajiw and its Sister Mountains deepens my sense of place and challenges me to confront uncomfortable emotions and (un)learnings that arise from spending time with Anishinaabeg Traditional Territory. Using an autoethnographic embodied movement method, I spent three days walking-with (skiing) on FWFN Reserve Lands and Traditional Territory in winter and spring 2026. I conducted a thematic analysis using NVivo software and manual methods. Grounded in the foundational theme of Shifting Understandings of Relationality and Responsibilities, three main themes emerged: Listening to Land; Negotiating Presence and Belonging; and Navigating Accountability and Imposition. Listening to Land reflects my bond with Land through awe, nurturing, and recognizing interconnected relationships. Negotiating Presence and Belonging involved acknowledging my entitlement and colonial privileges to access Land, especially FWFN Reserve Lands. Navigating Accountability and Imposition revealed my awareness of responsibilities, fears of imposition, and learning to accept uncertainty. Shifting Understandings of Relationality and Responsibilities highlights my evolving view of duties to Land and the Anishinaabeg. It reflects my intellectual and embodied development throughout the project and my ongoing commitment to accountability to Treaty obligations and to an ethical presence on Land, grounded in authenticity and humility. This study emphasizes the importance of providing White Treaty people with models for ethical engagement with Land and its original Peoples. Land is more than a setting for health-promoting activities; it is a source of belonging, responsibility, and relational accountability, and it is the foundation for understanding that human and planetary health are rooted in relationships.
Developing functional carbon dots for enhanced antimicrobial activity and development of ion-imprinted carbon dots for lead ion detection
(2026) Shahbandinejad, Ronak; Kang, Kang; Rakshit, Sudip; Khalid, Muhammad; Djafaripetroudy, Seyedrahman
The increasing need for efficient and renewable antimicrobial nanomaterials for biomedical and environmental applications has stimulated extensive research into novel carbon-based nanomaterials. In parallel, heavy metal contamination continues to pose a significant global environmental and public health concern. Lead (Pb2+) is a persistent environmental contaminant that poses a serious risk to human health even at trace amounts. Carbon dots (CDs), a new class of carbon-based nanomaterials, have attracted significant attention owing to their biocompatibility, fluorescence sensing, tunable surface chemistry, green synthesis, and antibacterial properties. However, the relationship between synthesis conditions, physicochemical characteristics, and antibacterial performance remains incompletely understood. This thesis aimed to optimize the hydrothermal synthesis of Zn/N-doped carbon dots derived from carboxymethyl cellulose (CMC) by investigating the effects of reaction temperature (250 °C, 300 °C and 350 °C) and time (1 h, 2 h, 3 h,) on their structural, optical, and antibacterial properties against a Gram-negative and a Gram-positive species (Escherichia coli and Staphylococcus aureus) using response surface methodology (RSM). The results showed that temperature is the dominant factor governing CDs properties, increasing crystallinity and fluorescence performance, with a maximum quantum yield (QY) of 71% and crystallinity of 48% achieved at 350 °C and 3 h. In contrast, optimal antimicrobial activity was observed at intermediate synthesis conditions, around 300 °C and 2 h, reaching a maximum zone of inhibition of 15.2 mm. Antioxidant activity was found to be more dependent on synthesis time, with the highest antioxidant activity observed in carbon dots synthesized for 1 h. Furthermore, this thesis explored the fabrication of ionic-imprinted carbon dots to enhance the selectivity and sensitivity of Pb2+ detection for environmental and biomedical monitoring. Overall, carbon dots synthesized at 300 °C for 2 hrs showed the best antimicrobial performance in both species, with MICs (minimum inhibitory concentrations) of 1 mg/mL for E.coli and 2mg/mL for S.aureus, with near-neutral surface charge and medium crystallinity compared to other samples and medium functional groups, indicating the synergistic effect of all properties instead of one enhanced property. Ion-imprinted carbon dots successfully demonstrated enhanced sensitivity and selectivity toward Pb²⁺ ions in blood and water samples, achieving a limit of detection (LOD) of 1.3 × 10⁻¹ μM.
Electrochemical depolymerization of lignin catalyzed by biomass-based magnetic-electrocatalyst
(2026) Chi, Jingzhi; Kang, Kang; Fatehi, Peadram
The depletion of fossil resources has intensified the search for sustainable carbon feedstocks, placing lignin, the most abundant renewable aromatic macromolecule in nature, at the center of modern biorefineries and circular bioeconomy strategies. Despite its enormous potential, lignin valorization remains challenging because its highly cross-linked three-dimensional architecture and exceptional chemical stability hinder efficient depolymerization and selective conversion. Electrochemical oxidation has emerged as an attractive alternative to conventional thermochemical approaches by operating under mild conditions without requiring strong chemical oxidants. Nevertheless, practical implementation remains constrained by two persistent challenges: heterogeneous powder catalysts are difficult to separate from reaction media after electrolysis, while inefficient mass transfer at the solid–liquid interface limits catalytic performance. To address these limitations, this thesis develops a novel strategy in which waste maple wood (MW) and the metal-rich industrial residue red mud (RM) are co-pyrolyzed to produce a low-cost magnetic biochar (MBC) heterogeneous electrocatalyst. Systematic optimization of the synthesis conditions identified M-MBC–5/1–900, prepared at 900 °C with a MW-to-RM mass ratio of 5 : 1, as the most active catalyst. During high-temperature carbothermic reduction, the iron oxides originally present in RM are transformed in situ into highly active zero-valent iron (α-Fe0) and iron carbide (Fe3C) nanophases, which become uniformly embedded within a highly graphitized carbon framework possessing a hierarchical mesoporous architecture. At the same time, the silica network derived from the intrinsic Si–O species in RM provides robust structural support, effectively suppressing nanoparticle sintering and agglomeration throughout pyrolysis. The resulting catalyst combines abundant accessible active sites with excellent structural stability, features that were consistently reflected in its superior electrochemical performance during repeated experiments. To account for the remarkable catalytic activity observed in alkaline electrolytes, experimental evidence directs our attention to the interfacial characteristics of MBC. The graphitized carbon matrix is proposed to establish strong π–π stacking and hydrophobic interactions with the aromatic backbone of lignin, overcoming electrostatic repulsion and promoting efficient enrichment of lignin molecules at the catalyst surface. Once concentrated at the electrochemical interface, lignin appears to undergo a distinctly time-dependent oxidation pathway likely dominated by reactive oxygen species, particularly hydroxyl radicals (·OH). During the initial 0–2 h of electrolysis, selective depolymerization is inferred to preferentially cleave the susceptible β–O–4 aryl ether bonds and Cα–Cβ linkages, fragmenting the polymeric backbone into value-added aromatic compounds, including vanillin, together with a limited amount of acetate. Extending the electrolysis period to 4–6 h fundamentally changes the reaction trajectory. The accumulated intermediates are deduced to undergo extensive over-oxidation, during which irreversible ring-opening (de-aromatization) reactions likely convert aromatic monomers into low-molecular-weight organic acids (LMWOAs), including formate, acetate, and various dicarboxylic acids. This progressive transformation is strongly supported by gel permeation chromatography (GPC), whose refractive index (RI) profiles reveal continuous fragmentation of the lignin macromolecular network. After 6 h of electrolysis, the Mw decreases dramatically from 2759 to 530 g mol–1, corresponding to an 80.8% reduction and providing compelling evidence for the highly efficient degradation of lignin. These findings collectively demonstrate that MBC electrocatalytic system offers advantages extending well beyond catalytic activity alone. The co-pyrolysis strategy lowers the specific energy requirement for catalyst synthesis by more than 50%, while electrolysis conducted under ambient conditions at an optimized lignin concentration of 5 g L–1 further reduces the overall energy demand of the conversion process. Equally significant is the incorporation of in situ generated magnetic nanophases, which impart excellent room-temperature magnetic responsiveness and enable rapid separation of the catalyst from the reaction mixture using only an external magnetic field. By simultaneously addressing catalyst recovery, mass-transfer limitations, and catalytic efficiency, this work establishes an integrated and economically viable platform for electrochemical lignin valorization. The proposed MBC catalyst therefore provides both fundamental mechanistic insights and practical technological support for advancing the sustainable and industrial-scale utilization of lignin within future circular biorefineries.