English

In this study, twenty lake catchments surrounding Iqaluit, Baffin Island, were assessed for trace element concentrations (Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Se, THg, V, Zn) in lake water, catchment soil, lake sediment, and moss (Hylocomium splendens). Additionally, the sources of each trace element were determined through the positive matrix factorization (PMF) model and enrichment factors (only in moss). Geogenic trace elements had the highest median concentrations (Fe>Al>Mn) throughout the study media and across the study catchments. Anthropogenic trace elements had the lowest median concentrations (Pb>As>Cd>THg) across the lake catchments, which were generally several orders of magnitude lower compared to geogenic elements. The PMF model identified trace elements associated with geogenic or anthropogenic sources, i.e., THg (47%), Cd (40%), Zn (34%), and Al (27%) were identified as originating from industrial emission sources deposited onto lakes because they accounted for a large proportion within the model.

Author Keywords: Arctic lake catchments, Biomonitoring, Enrichment factors, Positive matrix factorization model, Trace elements, Water chemistry

The synthesis of biaryls through transition metal catalyzed cross-coupling reactions has been instrumental for synthetic organic chemists. The Hiyama reaction, which features organosilicon derived cross-coupling partners with aryl chlorides, remains relatively underdeveloped compared to other cross-coupling reactions. In this thesis, it is demonstrated that bench stable Palladium N-Heterocyclic Carbene (NHC) precatalysts of the general type [(NHC)Pd(allyl)Cl] are highly active in the Hiyama cross-coupling of activated aryl chlorides with low catalyst loading. Notably, this research demonstrates that catalysts featuring sterically less demanding NHCs display higher activity in this reaction, which contrasts with other cross-coupling reactions. Preliminary mechanistic investigations including in situ reaction monitoring by 19F NMR spectroscopy have uncovered side reactions. These side reactions may explain the low catalytic performance observed with unactivated substrates. These studies could help to further develop this reaction and improve catalytic performance. Additional investigations have also been made into ligand development by altering the electronics of sterically hindered NHC ligands for use in other cross-coupling reactions.

Author Keywords: Catalysis, Cross-coupling, Organic Chemistry, Organometallics, Side Reactions, Synthesis

This study examines the atmospheric (synoptic) controls on snowmelt and snow-free season carbon dioxide (CO2) fluxes at Daring Lake, Northwest Territories. Atmospheric circulation patterns were derived from 500 hPa geopotential height and classified using the self-organizing maps artificial neural network. Snowmelt timing was not found to be influenced by atmospheric circulation patterns or large-scale teleconnection indices, but a shift from meridional to zonal atmospheric circulation marked the transition from pre-melt to melt period. Multiple linear regression identified heating degree days and incoming solar radiation as the most important meteorological predictors of melt length; however, the model would have benefitted from additional variables. Analysis of CO2 (net ecosystem exchange, NEE) during the snow-free season highlighted a strong correlation between NEE and temperature anomalies. Like the snowmelt period, no atmospheric circulation patterns were found to significantly influence NEE; however, these findings prompt further questions regarding snowmelt and CO2 fluxes in the Canadian low Arctic.

Author Keywords: atmospheric circulation, carbon fluxes, net ecosystem exchange, self-organizing maps, snowmelt, synoptic patterns

Animal migrations are ubiquitous and one of the most threatened ecological processes globally. Because of the multifaceted nature of migration – seasonal movements between home ranges – it can be difficult to tease apart the underlying mechanisms influencing this behaviour. It is necessary to understand these mechanisms, not only to deepen our fundamental understanding of migration in animals, but also because migrations in many species are vulnerable to environmental change. In Chapter 2, I first systematically identify the broad proximate drivers of migration and offer generalities across vertebrate taxa. I quantitatively reviewed 45 studies and extracted 132 observations of effect sizes for internal and external proximate drivers that influenced migration propensity. Through this meta-analysis, I found that internal and external drivers had a medium and large effect, respectively, on migration propensity. Predator abundance and predation risk had a large effect on migration propensity, as did individual behaviour. Of the studies that examined genetic divergence between migrant and resident populations, 64% found some genetic divergence between groups. In Chapter 3, I explore the genetic basis for migration and identified genes associated with migration direction from pooled genome-wide scans on a population of 233 migrating female mule deer (Odocoileus hemionus) where I identified genomic regions including FITM1, a gene linked to the formation of lipids, and DPPA3, a gene linked to epigenetic modifications of the maternal line. These results are consistent with the underlying genetic basis for a migratory trait which contributes to the additive genetic variance influencing migratory behaviours and can affect the adaptive potential of a species. Finally, in Chapter 4 I used a pedigree-free quantitative genetic approach to estimate heritability and sources of environmental variation in migration distance, timing, and movement rate of the same population of mule deer. I found low heritability for broad patterns of migration timing, and greater variation in heritability for behaviours during migration, with low heritability for distance and duration and high heritability for movement rate along the route. Insights into the genetic and environmental sources of variation for migration are critical both for the eco-evolutionary dynamics of migration behaviour, and for the conservation of species whose migrations may be vulnerable to environmental change. My thesis reveals that broad patterns of migration are driven largely by environmental effects while within these broad patterns, migration behaviour is driven to a measurable degree by genetic variation.

Author Keywords: heritability, migration, Odocoileus hemionus, reduced representation sequencing, whole genome sequencing

Spatial reasoning and spatial structures are relatively new areas of research in mathematics education. In this study of children exploring spatial conceptions of grid structures, twenty-one children (ages 4-9) were given a series of tasks involving square grids during virtual interviews. As a result of an ideal-type analysis of the qualitative data, a typology of conceptions of grids emerged showing five distinct categories sequenced from very early conceptions of square grids (as a series of isolated cells) to more coordinated structuring (as related and intersecting rows and columns). The five categories - Single Cell Structuring, Partial Unit Building, Whole Figure and Parts-of-Figure Noticing, Composite Unit Structuring and Coordinated Structuring - are described through illustrative examples. Students' gestures, language and diagrams were considered together when constructing the types. Interestingly, the spatial structure of grids was not readily apparent to many students and in fact was found to be complex for students to conceptualize. With minimal research on grids as a spatial structure in the mathematics education research field, there is strong potential for further investigation in this area.

Author Keywords: Grids, Mathematics, Spatial reasoning, Young Children

The study examines the adaptive reuse of historical and heritage industrial sites in Peterborough, Ontario. Industrial-heritage sites face several challenges when being subjected to adaptive reuse. These challenges are largely concerned with the contamination of sites and how industrial buildings and sites can be transformed into reusable sites. The study adopted a qualitative research design and analysis. The study addressed the research gap about nature of adaptive reuse of historic and heritage sites in Peterborough. The study primarily focused on the challenges, best practices, stakeholder initiatives, and the nature of structures in contexts of adaptive reuse in Peterborough. Based on the findings of the study, COVID-19, political will, contamination and the design of heritage and industrial buildings or sites pose a challenge to implementing adaptive reuse practices. These findings provide evidence for policymakers and decision makers on how to apply best practices to adaptive reuse and cultural heritage.

Author Keywords: Adaptive reuse, Cultural, Heritage, Historical, Industrial, Structures

Many species of shorebirds depend on stopover sites to rest and refuel during their long-distance migrations. To determine how shorebirds use migratory stopover sites, we tracked three species of shorebirds at two stopover sites in British Columbia, Canada from 2018-2021 during northward and southward migration using automated telemetry. Western Sandpipers (Calidris mauri) stayed longer at the Fraser River Estuary (4-8 days) compared to Tofino (2-6 days). We assessed habitat use of Sanderlings (Calidris alba), Semipalmated Plovers (Charadrius semipalmatus), and Western Sandpipers between beaches and mudflat at the Tofino stopover site. Time spent at the beach and mudflat habitats varied by species, tidal period, time of day, migration period, and human disturbance. This study shows that different stopover sites, and habitats within stopover sites, offer a unique set of characteristics used by birds exhibiting varying migration strategies, highlighting the importance of conserving a diversity of migration stopover locations and habitats.

Author Keywords: habitat use, human disturbance, length of stay, migration, shorebird, stopover site

ABSTRACT Patients who undergo chemotherapy often complain of a persistent 'brain fog' that can be present up to years after treatment ends. This fog is expressed as marked impairments in areas of learning, memory and mental health. As it stands, researchers have yet to determine the mechanism at fault for these impairments. The present experiment investigates if the neurogenesis that takes place in the subgranular zone of the hippocampus is suppressed as a result of chemotherapy treatment, and results in these impairments. In the following thesis, two models of chemotherapy are used to explore the treatment effects on Long-Evans rats. From here, three behavioural assessments and three measures of immunohistochemical techniques are used to explore the effects of Temozolomide on memory and anxious behaviour. Our findings support the current literature that suggests that Temozolomide suppresses adult hippocampal neurogenesis and results in cognitive and emotional impairments.

Author Keywords: adult hippocampal neurogenesis, Chemotherapy, Chemotherapy-Induced Cognitive Impairment, CICI, Long-Evans rats, Temozolomide

In 1995, Donald Judd's Chinati Foundation held its inaugural symposium titled "Art in the Landscape". During the roundtable discussion, walking artist Hamish Fulton asserted that there are fundamental differences between his art and American Land Art. Drawing on Fulton's assertion, this dissertation argues for the redefinition of British environmental art, conventionally called Land Art after the American tradition. Through the exploration of the work of several contemporary and living British artists, the British School of Aesthetic Chorography is articulated. The practice of aesthetic chorography involves an embodied experience of place, such as walking or gardening, which results in a creative response. This creative response is the place-work of aesthetic chorography and can take a plethora of forms including the attachment of language to place, the creation of an ephemeral marker, an image or a representation or the creation of a printed object which recalls the place in some way. Derived from the unfolding of this place-work, the role of language in art is a theme which is carried through the dissertation. The role of language in childhood, memory and constituting knowledge claims is also explored particularly as this relates to place and to loss and the conservational potential of language with respect to place is theorized in a place theory of language and a recollective theory of place. The conservational element of this work is further developed through the articulation of aesthetic chorography as a parochial tending practice which devotes attention to place as an experienced phenomenon. The persistence of parochial places and vernacular tending practices, however, require conservation. The heritage work of the Common Ground Trust in the UK which seeks to promote the "local distinctiveness" of places is explored and the keeping place is raised as a way of thinking about the engaged and living preservation of vernacular places, particularly in the face of environmental crisis.

Keywords: Aesthetics, Aesthetic Chorography, Art, Common Ground Trust, Concrete Poetry, Conservation, Critical Topography, Environmental Aesthetics, Environmental Ethics, Epistemology, Heritage, Keeping Place, Land Art, Landscape, Language, Lieu de Mémoire, Local, Memory, Monument, Parochial, Place, Place-work, Tending, Vernacular, Walking, Jonathan Bordo, Lionel L. Ferguson, Alec Finlay, Ian Hamilton Finlay, Hamish Fulton, Andy Goldsworthy, Donald Judd, Richard Long, Robert Macfarlane, Brian Nichols, Ferdinand de Saussure, Richard Skelton, Robert Smithson, James Turrell, W.J.T. Mitchell

Author Keywords: Aesthetic Chorography, Critical Topography, Heritage, Keeping Place, Landscape, Place

From the early days of colonization, the use of stereotypes has negatively impacted Indigenous women. One mode of transmitting those stereotypes is through fiction. This thesis examines Indigenous female characters in contemporary crime fiction, written by non-Indigenous Canadian authors, for evidence of stereotype depiction. Two novels were selected for this study, The Last Good Day by Gail Bowen, and Cold Mourning by Brenda Chapman. The books were critically scanned using characterization analysis for evidence the Indigenous female characters were depicted as stereotypical Indian Princess or squaw. Results indicated the characters did possess some traits associated with the stereotypes, but overall, the characters reflected a realistic depiction of Indigenous women. The characters are authentic, relatable Indigenous women in the two books discussed, and are examples of how characters who are Indigenous can be respectfully depicted in Canadian crime fiction.

Author Keywords: Colonization, Crime Fiction, Indigeneity, Indigenous women, Relationships, Stereotypes