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Cognitive impairments, such as memory loss, are a frequent and devastating co-morbidity associated with epilepsy. The neurobiological mechanisms through which recurrent seizures induce cognitive impairments are not well understood. New neurons born after seizures develop abnormal morphological and functional characteristics that promote network hyperexcitability and hippocampal dysfunction. Previously, we found that kindling dramatically increases the rate of neurogenesis at early stages of seizure development, followed by a long-term suppression at later stages. These changes in the rate of cell proliferation coincides with aberrant modifications in the migration, excitability, and functional integration of these new neurons. It has been suggested that the long-term consequences of seizure-induced neurogenesis contributes to the development of cognitive impairment seen in chronic epilepsy. However, direct experimental evidence has been limited. The present series of experiments sough to determine if blocking aberrant seizure-induced neurogenesis can reduce cognitive deficits associated with chronic epilepsy. Our findings suggest that chronic seizures impair the ability of rats to differentiate between similar contexts. In addition, blocking aberrant seizure-induced neurogenesis through treatment with the cytotoxic agent temozolomide was capable of preventing some of the deficits in context discrimination learning when neurogenesis levels were reduced to non-epileptic control levels. This research provides further support of targeting aberrant neurogenesis as a novel treatment to restore cognitive functioning in individuals living with epilepsy.

Author Keywords: Amygdala kindling, Dentate gyrus, Hippocampus, Neurogenesis, Pattern separation, Seizures

Three experiments examined whether semantics is activated automatically by testing whether Arabic digits (e.g., 4), number words (e.g., four), and non-number words (e.g., rat) activate semantics in the absence of central attention within the Psychological Refractory Period (PRP) paradigm. In all three experiments, subjects performed colour discriminations as Task 1. In Task 2, subjects performed magnitude comparisons on digits (Experiment 1) and number words (Experiment 2) and size comparisons on animal words (Experiment 3). Task overlap was controlled by varying stimulus onset asynchrony (SOA). A distance effect arose in Task 2 and yielded underadditive effects with decreasing SOA for both digits and number words, consistent with these notations activating semantics in the absence of central attention, or automatically. A distance effect also arose for animal words, but it was additive with SOA, inconsistent with non-number words activating semantics automatically.

Author Keywords: Automaticity, Central attention, Dual-task, Numerical cognition, Semantics, Word recognition

Rising populations of Lesser Snow and Ross' geese (hereafter collectively referred to as light geese) breeding in the North American Arctic have caused significant environmental change that may be affecting some populations of nesting shorebirds, which in contrast to geese, have declined dramatically. In this thesis I examine the indirect effects of light geese on sympatric-nesting shorebirds. I first conduct a literature review of the effects of light geese on northern wildlife and outline multiple mechanisms in which geese may affect shorebirds in particular. Using bird survey data collected in plots situated across the Canadian Arctic from 1999 to 2016, I then identify spatial effects of light goose colonies on shorebird, passerine, and generalist predator densities. The densities of cover- nesting shorebirds and passerines were depressed near goose colonies while the densities of open-nesting shorebirds were less so. Next, using habitat data collected at random sites and shorebird nest sites situated at increasing distances from a goose colony on Southampton Island, Nunavut, I outline the effects of geese on shorebird nest site selection. I found that the availability of sedge meadow and amount of lateral concealment increased as a function of distance from goose colony; cover-nesting shorebirds selecting nest sites with less concealment and sedge meadow near the colony. Then, to characterize spatial effects of light geese on predators and risk of predation I used time-lapse cameras and artificial shorebird nests placed at increasing distances from the goose colony. Activity indices of gulls, jaegers, and foxes were all negatively correlated with distance from the goose colony while the reverse was true for artificial nest survival probability. Finally, I relate changes in ground cover to goose use and link these changes to variation in invertebrate communities. I then use DNA metabarcoding to characterize the diet of six shorebird species across study sites and identify inter-site variation in the biomass of dominant shorebird prey items. Prey item biomass was elevated at the two study sites near the goose colony potentially indicating an enhancing effect of goose fecal deposition. Overall, I show that light geese interact with shorebirds in multiple ways and negatively affect their habitat availability, nest site selection, and risk of predation, effects that likely outweigh the positive effects of enhanced prey availability.

Dissolved organic matter (DOM) in oceans provides nutrients and ultraviolet radiation protection to microbes. Some DOM compounds can chelate with metals, including copper, controlling their transport and bioavailability in marine systems. As copper functions as both a nutrient and toxicant, studies into the chemical structures of Cu-ligands is important, however currently limited. In this thesis, the chemical composition of total and Cu-binding DOM is investigated using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in the Canadian Arctic and North Pacific. Chapter 2 reveals chemical differences in DOM composition between the southern and northern Canada Basin, revealing the influence of terrestrial and biological sources. Chapter 3 shows the uniqueness of Cu-binding ligands found in the Canadian Arctic and North Pacific Ocean. Studying the composition of DOM gives insight into the chemical diversity of marine DOM, helping to predict the effects of a changing climate on marine ecosystems.

Author Keywords: biological, dissolved organic matter, fluorescence, immobilized metal-ion affinity chromatography, mass spectrometry, terrestrial

This study provides important perspectives and guidance for educators in Ontario to assist in integrating Indigenous content into public education programs – both in schools and other community educational settings. It explores how Indigenous worldviews provide unique insights for holistic education and learning how to live sustainably in place. The study also focuses on approaches to education, comparing Eurocentric and Indigenous philosophies and pedagogies, as indicators of differing value systems. Through a combination of literature review and personal interviews with eleven influential Indigenous and non-Indigenous educators in the Peterborough area, the study explores the potential for Indigenous perspectives to enhance the wellbeing and personal learning journey of all students, regardless of their backgrounds. The research concludes with recommendations for educators on how to begin integrating Indigenous Knowledge throughout programming in appropriate, respectful ways that celebrate diversity, develop positive relationships and build healthier, more sustainable communities.

Author Keywords: Education, Environment, Indigenous Knowledge, Pedagogy, Reconciliation, Worldviews

This study explored teacher infusion of Indigenous curriculum content through interviews with ten non-Indigenous teachers of social studies and history. The interviews centered on teacher perceptions of preparedness to implement Ontario's recent TRC curriculum revisions, which include more about the contributions, histories, cultures, and perspectives of Indigenous peoples. A brief analysis of Ontario's First Nation, Métis, and Inuit Education Policy Framework is included, alongside critiques of the Eurocentrism at the heart of education systems. The interviews revealed that many of the teachers were committed to Indigenous education and learning more, but they felt unprepared and lacked resources to teach Indigenous curriculum content with confidence. This study highlighted the critical role of settler teachers in Indigenous education and the importance of teachers undertaking settler unsettling in order to be effective and appropriate in Indigenous curriculum delivery. Individual changes must occur alongside educational system decolonization with a particular focus on teacher preparation.

Author Keywords: cognitive imperialism, Indigenous Education, Ontario, settler educator, settler unsettling, TRC curriculum

Deep Neural Networks (DNNs) have reached human-level performance in numerous tasks in the domain of computer vision. DNNs are efficient for both classification and the more complex task of image segmentation. These networks are typically trained on thousands of images, which are often hand-labelled by domain experts. This bottleneck creates a promising research area: training accurate segmentation networks with fewer labelled samples.

This thesis explores effective methods for learning deep representations from unlabelled images. We train a Restorative Autoencoder Network (RAN) to denoise synthetically corrupted images. The weights of the RAN are then fine-tuned on a labelled dataset from the same domain for image segmentation.

We use three different segmentation datasets to evaluate our methods. In our experiments, we demonstrate that through our methods, only a fraction of data is required to achieve the same accuracy as a network trained with a large labelled dataset.

Author Keywords: deep learning, image segmentation, representation learning, transfer learning

The risks and benefits of sexting within an intimate relationship were explored. The present study focused on sexual gratification, relationship benefits, and sexual communication as benefits and risky sexual behaviour, unethical forwarding, and infidelity as risks. A cross-sectional online survey of both undergraduate students and a community sample was used. Results indicated that sexual gratification, relationship benefits (sexual and relationship satisfaction, relationship quality, and commitment), and sexual communication are related to sexting. It appears that risky sexual behaviour is not associated with sexting, instead those who sext frequently engage in more safer sex behaviours than those who sext infrequently. Unethical forwarding does not appear to happen very often in the context of intimate relationships. Lastly, the current research indicates that some participants are sexting secondary partners, and many consider sexting secondary partners infidelity. These results show that there are both risks and benefits of sexting, which can be used to develop sext education and therapeutic programs.

Author Keywords: infidelity, relationship benefits, Sexting, sexual behaviour, sexual communication, sexual gratification

Stone axes and adzes first appeared in the eastern Gobi Desert at 8.0 cal BP and were incorporated into the technological package. At the same time, changes in local ecological conditions reflect a transition from continuous grass/shrub-steppe across the Mongolian Plateau to the development of dispersed patches of dune-field wetland oases and high-elevation forests. This thesis focuses on exploring the adoption and function of axes and adzes in the eastern Gobi Desert and their relationship to the development of these new forested ecologies. Using an experimental and use-wear approach, I analyze 29 axes and adzes from four sites in the eastern Gobi Desert of Mongolia and Inner Mongolia. Results indicate that axes and adzes were primarily used for woodworking but include other activities. Furthermore, the adoption and manufacture of axes and adzes represent an increasing investment in producing formal technologies as resources within these new diverse ecological patches were intensively utilized.

Author Keywords: Adaptation, Axes and Adzes, Eastern Gobi Desert, Neolithic, Technological Intensification, Use-Wear

The use of threats to feelings of intimacy and belonging, also known as

relational aggression, has been previously explained using attachment representations

and attributions in childhood. However, the combined role of attachment

representations and attributions in explaining relational aggression in adult peer and

romantic relationships has been unexplored. This study tested the associations

between attachment, attributions, and relational aggression with a specific focus on the

mediating role of attributions. A final sample of 258 undergraduate university

students completed self-report surveys and vignettes to measure the variables of

interest. Results suggested that attachment predicted relational aggression but, with

one exception, attributions did not explain unique variance in relational aggression

after controlling for attachment. Interestingly, hostile attributions mediated the

relationship between dismissing attachment to romantic partners and romantic

relational aggression. Therefore, individuals' attachment representations directly

influenced their levels of relational aggression in relationships regardless of their

attributions.

Author Keywords: Adulthood, Attachment, Attributions, Mediation, Relational Aggression