3855 research outputs found
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Genetic resistance to anticoagulant rodenticides and pathways of non-target exposure in Ontario
No full textGenetic resistance to anticoagulant rodenticides (ARs) is a worldwide phenomenon that has never been investigated in Canada’s commensal rodents. Additionally, the pathways of non-target rodent AR exposure and secondary poisoning are unknown in Ontario. The VKORC1 gene of 55 house mouse (Mus musculus) and 54 Norway rat (Rattus norvegicus) samples collected from 3 regions of Ontario was examined for known and novel resistance mutations. Resistance was absent from rats, but present in 98% of mice, with mutations known to cause resistance to first-generation ARs and bromadiolone. Homozygous resistant mice were more common in heavily developed, low-income, high population density areas. Additionally, only 11 out of 111 non-target Peromyscus leucopus trapped near ongoing urban rodenticide operations tested positive for an anticoagulant. Given these findings, we recommend that second-generation anticoagulant rodenticides (SGARs) be used only for the control of house mice where non-target rodents are absent
Back to normal: a salutogenic approach to remission spaces for childhood cancer survivors and their family
No full textAdvances in childhood cancer research within Ontario and Canada have allowed for an increase in the 5-year survival rate. While the guidelines and care for treating the disease in its active state are well established, once in remission quality of care decreases significantly. Existing remission clinics only monitor for the physical symptoms of adverse effects from cancer treatment and not the psychological and psychosocial difficulties that affect the quality of life of these survivors and their families. Due to the increasing population of survivors and the likelihood of adverse effects, remission care should be restructured to not only address existing late effects but also enhance the survivors’ health before treatment is needed. This shift from a pathogenic approach to a salutogenic one not only addresses the gap within the pediatric oncology space but also creates a new precedent for health care for survivors of childhood cancer
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
Curating place: restoring Copper Cliff's industrial sites through environmental science and community heritage design
No full textThis thesis investigates the complex interrelationships between environmental restoration, industrial activity and the community identity and heritage within Copper Cliff, a historically mining-dependent community in Sudbury, Ontario. Situated on the Canadian Shield, this region makes for a unique case study in urban regeneration. Inaugurating as an industrial area seriously afflicted by environmental degradation and metamorphosing into a symbol of ecological recovery. This study, therefore, addresses the challenge of maintaining environmental progress while taking into account social and economic development. Utilizing an interdisciplinary strategy that combines restorative ecology and cultural heritage. The study suggests a model for revitalizing Copper Cliff’s industrial sites into multi-functional spaces that serve both the ecological and social dimensions of the town. The thesis supports historical memory and place-making strategies to highlight the community’s industrial and cultural past, ensuring that the architectural gestures not only respect history but contribute to the ongoing story of “place”.
Through an ethnographic approach that incorporates walking tours as a tool for community engagement, the research seeks to deepen the connection between residents and their transformed environment. The study is centered on an exploration of the socio-cultural influences of industrialization and the ongoing healing of the land. Curating design methods for sustainably restoring urban areas while preserving Copper Cliff’s past and promoting an inclusive and resilient future. Offering insights that could inform similar initiatives in other industrial communities
Mino Goondawin: exploring co-creation in the design of the Atikameksheng Gathering Place
No full textThe Truth and Reconciliation Commission’s 94 Calls to Action have inspired reconciliation efforts across Canada, highlighting the need to acknowledge the disrupted history of Indigenous peoples on Turtle Island. Understanding the damaged relationships with the natural and built environment emphasizes our responsibility to respect Indigenous rights and sovereignty. Acknowledging Indigenous worldviews rooted in relationality, reciprocity, and connection to land and community is central to this. Indigenous methodologies such as oral histories, ceremonies, and land-based practices prioritize process over product and support co-creation grounded in trust and respect.
This thesis explores co-creation in design, grounded in Indigenous knowledge systems and guided by the principle of Mino Goondawin. It emphasizes the role of design and decolonization in fostering meaningful collaboration that respects and integrates Indigenous values. Applied through the Atikameksheng Gathering Place design, this work highlights how Co-Creation can strengthen cultural resurgence and placekeeping in architecture by centering reciprocal relationships
The moderating effects of gender, emotion, and culture on the relationship between organizational justice and organizational citizenship behavior
No full textModern organizations are viewed as microcosms of bigger society; therefore, their implementation of justice reflects the realization of justice throughout larger society. The concepts of organizational justice and organizational citizenship behaviour (OCB) have gained a lot of attention in the field of organizational behaviour. While organizational justice refers to employees' views of fairness in the workplace, OCB refers to discretionary behaviours that go beyond the official obligations of a job. Previous research has related perceptions of organizational justice to a variety of outcomes, including job satisfaction, counterproductive work behaviour, and organizational commitment. The current study, however, looks at the moderating effects of gender, emotion, and culture on the relationship between organizational justice and OCB. The study investigated the relationship between organizational justice and OCB at their dimensional levels (distributive, procedural, and interactional justice), as well as the behaviours people exhibit towards one another and the organization (OCBI and OCBO). An online survey was used to measure the variables among employed individuals (N = 310) from a variety of occupations. The findings supported a positive association between all dimensions of organizational justice and OCB, with interactional and procedural justice being the strongest predictors of OCBI and OCBO. The study found that the cultural orientation of collectivism and low-power distance considerably influenced the perception of justice, whereas the cultural orientation of individualism and high-power distance had a negative association with both OCBI and OCBO. This shows that employees from these cultural backgrounds may be less likely to participate in OCB, even when they perceive fairness. Gender and emotion were largely non-significant as moderating variables, implying that perceptions of justice transcend gender differences and emotional states. These findings emphasize the significance of conducting a comprehensive examination into the relationship between organizational justice and OCB, as well as the potential moderating effects of gender, emotion, and culture on this relationship. Additional implications for research and practice are discussed
Examining the role of carotenoids and retinoids in modulating cellular response to oxidative stress: an evidence-based approach
No full textOxidative stress, resulting from an imbalance between reactive oxygen species (ROS) production and antioxidant defense systems, plays a critical role in cellular damage and the progression of diseases such as neurodegeneration, cardiovascular disorders and cancer. Carotenoids and retinoids, naturally occurring compounds with potent antioxidant properties, modulate oxidative stress by scavenging free radicals, preventing lipid peroxidation and regulating gene expression. This review explores the bioavailability, metabolism and molecular mechanisms of carotenoids, including β-carotene, lutein, and lycopene. Additionally, it investigates the influence of retinoic acid on gene regulation through retinoic acid receptors (RARs) and retinoid X receptors (RXRs), emphasizing their impact on cellular differentiation, apoptosis and oxidative defense. The therapeutic potential of carotenoids in neurodegenerative disorders, cardiovascular health and cancer treatment is discussed. The review concludes that while carotenoids and retinoids offer significant protective benefits against oxidative stress, their clinical application requires careful consideration of bioavailability, dosage and individual genetic variations to maximize therapeutic outcomes
Optimization of pilot bioleaching for enhanced metal recovery: scale-up bioreactor, comparative bio-oxidation analysis, and advancing the continuous pyrrhotite bioleaching process
No full textThe Sudbury region’s long history of nickel (Ni) and copper (Cu) mining has led to significant tailings accumulation, deemed waste due to processing limitations of past technologies. These tailings still contain valuable minerals, but their maintenance poses high costs and environmental risks. Due to weathering, the sulphide minerals in the tailings generate acid, facilitated by indigenous microbes, and contaminating nearby water bodies and surrounding land. Increasing regulatory demands and environmental concerns necessitated long-term tailing management and remediation plans. Research has highlighted bioleaching as a promising technology for treating low-grade minerals and environmental cleanup. The microbial assisted process has been proven effective for gold, Cu, and cobalt (Co) extraction, and has shown potential for pyrrhotite (Po) contained in tailings but is short of larger-scale testing for industrial feasibility. This study developed pilot-scale bioreactors to bioleach Ni and Co from Po tailings, using three 50-liter reactors in both batch and continuous modes. Key investigations addressed particle homogeneity within the reactors, gas mass transfer, and cooling needs due to exothermic nature of the bioleaching reactions. Results showed effective metal solubilization and valuable operational data for scale-up and techno- economic analysis. The pilot tests compared the bioleaching performance with bench-scale systems, using BACOX technology with microbial consortia to solubilize arsenic from arsenopyrite and release gold. The pilot reactors improved arsenic, iron solubilization, and overall metal recovery, despite a longer microbial adaptation period required. The continuous bioleaching of Po tailings using the CanmetMINING process to set a benchmark for pH control was essential for efficient Ni and Co recovery while minimizing iron passivation. Adjusting particle size and pH control improved the outcomes, with Acidithiobacillus caldus and Sulfobacillus spp. identified as key bioleaching microbes. The process successfully solubilized up to 93.4% Ni and 95.4% Co, with iron levels reduced to 2.88% in the PLS. However, issues with slurry flow rates and pump blockages underscored the need for further optimization of the feed transfer systems. Key findings included the pilot reactor’s superior metal recovery and homogeneity and the importance of reduced particle size and pH control. Recommendations for industrial scale-up include pretreatment steps like grinding to ensure consistent particle size for efficient bioleaching
Medication provoked dysbiosis: emerging therapies targeting the micobiome
No full textThe intestinal microbiome is a dynamic, diverse, and variable community of microorganisms that plays a very fundamental role in digestion, immunity, and overall health. It influences the host in digestion, production of necessary metabolites, tuning of the immune response, and acting as a barrier against pathogenic organisms. Probiotics are live microorganisms that confer health benefits upon ingestion, especially playing highly important role in the restoration of microbial balance. They improve intestinal barriers, regulate immune responses, and produce short-chain fatty acids important for gut health maintenance. Drugs, especially antibiotics and Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), can have quite significant alterations in microbial diversity, mostly a reduction of the population of beneficial bacteria as a consequence of their specific pharmacological action. This review focuses on different pharmaceutical-induced changes in gut microbiota, how disrupted microbiomes further promote the development and progression of various life-threatening diseases. The role of probiotics, prebiotics and post-biotics in restoring eubiosis, a healthy microbiome is discussed
Evaluating the effectiveness of an innovative road mortality mitigation design for at-risk reptiles in eastern Georgian Bay, Ontario
No full textRoad mortality poses a serious threat to reptiles, yet the effectiveness of mitigation strategies is often compromised by poor durability and designs that fail to account for species-specific behaviours and morphology. I evaluated the effectiveness of a 1-m-tall, concave, High-Density Polyethylene (HDPE) fence paired with ecopassages (3 aquatic, 1 terrestrial) installed along a residential road bisecting a wetland in eastern Georgian Bay. Using a 4-year Before-After- Control-Impact (BACI) design, I found a 26% decrease in reptile observations post-mitigation and a marginally significant interaction between Site (Control, Impact) and Period (Before, After), providing some support that the mitigation was effective. However, opportunistic observations indicated that the fence was not preventing reptiles from accessing the road. Camera traps installed in the ecopassages recorded 2371 crossings by 13 reptile species, and turtle species composition in the ecopassages was not significantly different than that in the road-adjacent wetland based on a 2-year mark-recapture study. Finally, in situ behavioural assays using Eastern Foxsnakes (Pantherophis vulpinus) showed that the concave fence successfully prevented climbing in 23 assays with 18 individuals, although one large snake (>120 cm snout-vent-length) used the supporting rebar to surmount the fence. Additionally, 4 individuals exhibited increased climbing attempts of the fence and supporting rebar in repeated trials, suggesting potential for learned behaviour. Overall, I concluded that the concave fence design and ecopassages were mostly effective, but with the important caveat that reptiles could still access the road due to the short length of the fence. To improve the efficacy of this design, I recommended extending the fence length past the wetland edge, modifying the fence overhang to prevent snakes from climbing, utilizing pre-existing culverts as ecopassages, and installing ecopassages near fence ends.Georgian Bay Mnidoo Gamii Biosphere, Ontario Graduate Scholarship, St. Lawrence Seaway Climate Change Scholarship, Natural Sciences and Engineering Research Council (NSERC; Discovery Grant to JDL), Species at Risk Stewardship Program (Ministry of the Environment, Conservation and Parks), Habitat Stewardship Program for Species at Risk and Community Nominated Priority Places – Canada Nature Fund (Environment and Climate Change Canada), Ganawenim Meshkiki (GMI) and Maamwi Anjiakizwin (Together, Land, Renewal, and Life). In kind support was provided by Township of Carling, Killbear Provincial Park, Shawanaga First Nation and Wasauksking First Nation