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Moral Identity: From Theory to Research
Get PDFMoral identity, often defined as the importance or centrality of moral values to a person’s sense of self, has long been understood to play an important role in moral functioning. However, critical gaps remain regarding its development, cross-context stability, and behavioural significance. This dissertation addresses these gaps in three empirical studies, providing new insights into the nature and function of moral identity across the lifespan and in daily life.
The first study (Chapter 2) explores developmental trends in moral identity, testing predictions from moral identity goal theory (Krettenauer, 2022). Using a cross-sectional sample spanning adolescence to old age, the study finds that with age moral identity becomes increasingly informed by abstractly rather than concretely construed values, and increasingly underwritten by internal rather than external motivation. The second study (Chapter 3) examines the stability and malleability of moral identity using experience sampling methods (ESM). By tracking momentary fluctuations in moral identity salience in a sample of Canadian university students over the course of a week, the study demonstrates that moral identity varies significantly within individuals across contexts while also showing stable between-person differences. Further, it shows that within- and between-person differences are related to a variety of morally relevant events experienced in everyday life. The third study (Chapter 4) also employs ESM to explore how moral and immoral action undertaken in daily life can be independently predicted by both within-person fluctuations and between-person differences in the salience and motivation of moral identity. It finds that while variation at both of these levels in moral identity is predictive of discrete actions and behavioural dispositions, this relation is more consistently found and stronger at the within-person level. Moral identity motivations are also found to be uniquely predictive of behaviour, in context-dependent ways.
Together, these studies provide a comprehensive view of moral identity as a dynamic construct that develops over the lifespan, exhibits trait-like stability while also responding to situational factors, and profoundly influences behavior. By bridging developmental, socio-cognitive, and individual difference perspectives, this research contributes to a more nuanced understanding of moral identity
Applying Machine Learning and Optimization Algorithms to Perform Feature Selection
No full textThe objective of feature selection in the realms of machine learning and data mining is integral, serving as an efficient mechanism to eradicate redundant or irrelevant features, and subsequently augmenting the performance of predictive models. In the contemporary landscape of big data, with the escalating dimensionality of datasets, the efficacy of traditional feature selection methodologies is compromised, due to their computational complexity and ineptitude in addressing the curse of dimensionality. This thesis posits a pioneering feature selection framework that amalgamates machine learning with advanced optimization algorithms. The methodology employs a Support Vector Machine (SVM), in conjunction with a cutting-edge metaheuristic algorithm, namely the Black Widow Optimization (BWO) algorithm, as a means to address feature selection (FS) challenges. The SVM, renowned for its robustness and ability in addressing complex classification dilemmas, was strategically amalgamated with the binary form of BWO. Additionally, this study delves into the integration of a recently formulated K-Nearest Neighbor (KNN) algorithm with BWO, utilizing an innovative set of classification metrics. The empirical evaluation of the proposed methodologies was conducted through two distinct experimental sets. The inaugural set of experiments was dedicated to the comparative ii analysis of the binary BWO with SVM (BBWO-SVM) against its counterpart, the binary BWO with KNN (BBWO-KNN). The subsequent set of experiments aimed to place the performance of BBWO-SVM and BBWO-KNN against six globally renowned metaheuristic algorithms. Both experimental sets utilized a comprehensive array of metrics, encompassing the number of features selected, accuracy, recall, precision, and the F1-Score, as the basis for performance comparison. The datasets employed for these experiments comprised 28 public datasets of varying magnitudes, as sourced from the UCI repository. The findings gleaned from the experimental analysis attest to the superior performance of BBWO-SVM, as it transcended the traditional algorithms and manifested exceptional prowess in enhancing classification performance across an array of benchmark datasets. The empirical evidence further substantiates the potential of BBWO-SVM as a versatile tool applicable across diverse domains, inclusive of healthcare, finance, and cybersecurity
Anoxia and Re-oxygenation at Colder Temperatures in Goldfish (Carassius auratus): Effects on Oxidative Stress and Metabolites
No full textUnder the ice of ponds and lakes, goldfish (Carassius auratus) can survive weeks of anoxia at low temperatures by conserving ATP and by reducing their metabolic rate and relying on liver glycogen stores to meet their ATP demands using glycolysis. The following period of re-oxygenation is also known to be damaging in most vertebrates because it can lead to the generation of reactive oxygen species (ROS) that can cause oxidative damage to lipids, proteins and nucleic acids. Anoxia tolerant vertebrates such as the goldfish and crucian carp (Carassius carassius) accumulate reduced molecules with anoxia, overwhelming the electron transport system, producing ROS, and thus oxidative stress during re-oxygenation. Primary antioxidant defenses and pathways regulating ROS production are thought to minimize oxidative stress. In natural, temperate environments, fishes normally experience anoxia and re-oxygenation at colder temperatures. Yet relatively few studies have directly addressed how important cold-water temperatures are in limiting oxidative damage to goldfish during anoxia and re-oxygenation. In this study, the effects of cold-water acclimation (4°C) on the physiological responses of goldfish to anoxia and re-oxygenation were studied. Goldfish were acclimated to 4 °C or 14°C for 3 months, followed by 96 h or 24 h of anoxia exposure and a 12 h period of re-oxygenation. Tissues (liver, muscle, blood) were collected for analysis of antioxidant enzyme activities, oxidative damage, glycogen stores, and metabolites. Temperature acclimation resulted in 1.5-fold greater superoxide dismutase (SOD) activity and 2.2-fold lower glutathione peroxidase (GPx) activity in the normoxic liver at 4°C. Anoxia exposure resulted in no oxidative damage or changes in antioxidant enzyme activity in the liver or muscle at either temperature. Notably, liver glycogen did not significantly decrease during anoxia at 4°C, but a 70% decrease in liver glycogen was observed following 24 h of anoxia at 14°C and sustained through 12 h of re-oxygenation. Both blood glucose and lactate were elevated following anoxia at both temperatures, consistent with a greater reliance on anaerobic glycolysis. Significant anoxic ethanol accumulation occurred in the blood, which took longer to eliminate at 4°C during subsequent re-oxygenation. These findings support the hypothesis that reduced metabolic rates at cold temperatures reduce energy demands and the accumulation of anaerobic metabolites. In conclusion, oxidative stress in goldfish during re-oxygenation is prevented by mechanisms that do not involve changes in antioxidant enzyme activity, but recovery from anoxia is faster at colder temperatures. The robustness of goldfish to periods of anoxia and re-oxygenation, especially at colder, more environmentally relevant temperatures, represent adaptations that have allowed them to occupy niches that are unsuitable for other freshwater fishes
Lactate\u27s Role in Appetite Suppression
No full textOnce considered metabolic waste produced during exercise, lactate is now known to have diverse roles in biology. Muscle-derived lactate can travel through the bloodstream and be taken up by other tissues and i) oxidized, ii) converted to glucose via gluconeogenesis, or iii) bind to its receptor to trigger molecular signaling cascades. Lactate has been described as a “myokine” capable of inter-organ crosstalk and compelling evidence demonstrates lactate’s role as a signalling molecule in pathways related to the regulation of appetite. The purpose of this dissertation was to further elucidate lactate’s role in appetite regulation using series of studies aimed at manipulating lactate concentrations while attempting to minimize other extraneous factors that could influence appetite regulation. The main findings of this dissertation include: 1) oral sodium lactate ingestion does not increase blood lactate concentrations and is not an effective way to assess lactate’s effects on metabolism (Study #1); 2) using human studies with exercise intensity or a different exercise modality (resistance training) demonstrated exercise-induced lactate accumulation coincides with reductions in acylated ghrelin (Studies #2 & #3); 3) using a systematic review of all available work on exercise-induced lactate accumulation and post-exercise acylated ghrelin concentrations, statistical synthesis demonstrates an association between lactate and the acylated ghrelin (Study #4); 4) blood lactate accumulation following exercise does not alter the appetite regulating neuropeptides (or that peripheral blood samples do not reflect the central concentrations) (study #5); and finally 5) lactate accumulation due to exercise, injection, or oxamate administration (lactate dehydrogenase inhibitor) in a mouse-model does not alter the signaling cascades involved in appetite regulation. Overall, the results of this dissertation have improved our understanding of lactate’s role in appetite regulation and will guide future research necessary to fully elucidate the involvement of lactate in appetite-regulation
Fully Alive: Tending to the Soul in Turbulent Times
Get PDFReview of Fully Alive: Tending to the Soul in Turbulent Times by Elizabeth Oldfield (Grand Rapids, MI: Brazos Press, 2024
Watercolours from The Garbage Poems
Get PDFCover art by April White. Watercolours adapted from The Garbage Poems
This did not have to happen
Get PDFAn elegiac poem on the cost to the planet and to all life on earth of the manufacture, use, and disposal of plastic products
Requiem for a Gull: Two Poems
Get PDFA seabird’s death is mourned through “Requiem for a Gull” by Joanna Streetly, while Dip & Skim exlores the omnipresent nature of waste
It’s Time for a Change: A Proposal to Abolish Solitary Confinement From Canadian Prisons
Get PDFDespite Canada’s reputation for being a leader in human rights, its treatment of prisoners requires a closer examination. In particular, prisoner and human rights advocates have widely criticized the use of solitary confinement in Canadian federal and provincial prisons as a form of torture. Solitary confinement imposes excruciating and demeaning conditions on prisoners, jeopardizing their mental and physical welfare. Following court decisions deeming solitary confinement unconstitutional, the federal government replaced the formal use of solitary confinement with structured intervention units. However, these units continue to be a reformulated version of the original practice, sustaining the torturous conditions subjected to inmates. Implications of current practices include a negative impact on inmates\u27 general well-being and a violation of prisoners’ rights under the Canadian Charter of Rights and Freedoms and international law via the Nelson Mandela Rules. This policy proposal calls for the end of solitary confinement and structured intervention units in all Canadian prisons. While there are some challenges to doing so, benefits to ending the practice include reduced correctional costs, enhanced safety for the general prison population, and increased reintegration success
Fallow Fields or Fertile Ground: Analysing Food Governance in a Changing World
No full textOur food systems are failing us. In particular, industrial food systems fail to deliver healthy, adequate food to billions of people (FAO et al. 2019; FAO et al. 2024) and have led to increased instances of mental health crises for farmers (Jones-Bitton 2019; Younker & Radunovich 2021). In addition, industrial food systems contribute to the devastating impacts of a warming climate (IPCC 2021), biodiversity loss (WWF 2021), and soil erosion (Wise 2019; Badreldin and Lobb 2023) worldwide. Yet, little structural change has occurred in the way agriculture is governed and the problems created by industrial agriculture are becoming increasingly entrenched. Given this context, the research in this dissertation asks:
Why, in an era of converging crises, has agricultural policy remained largely unchanged and supportive of industrial agriculture practices?
The research included in this dissertation is underpinned by current academic literature that constructs my understanding of food systems challenges and changes in global governance over the past decades (Chapter 2). Presented as three research papers (Chapters 4, 5, and 6), each chapter focuses on a unique aspect of governance and is enabled by the different methods laid out in Chapter 3. Chapter 4 lays out the methods and methodology used for the three research papers (Ch. 4, 5, and 6) included in this dissertation. Chapter 4 focuses on actor arrangements and power in Canadian federal agricultural policy while Chapter 5 focuses on how different food systems actors experience multistakeholder governance arrangements. Different examples of how place-based, rights-centred governance arrangements can offer a more equitable outlook for food systems are assessed in chapter 6. The concluding chapter (7) provides a set of tools and strategies to help bridge the gap between the findings of Chapters 4 and 5 with the examples of transition in Chapter 6