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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

Climate change affects birds' reproductive ecology by altering breeding timing, distribution, and habitat suitability. Snowmelt patterns complicate these changes affecting habitat availability and suitability for birds and their arthropod prey. Snow varies as a function of both large-scale climate patterns and local-scale topography. I used elevational gradients as a proxy for local- scale snow impacts, investigating how elevation affects arthropod abundance, and nest placement, initiation, fate, and habitat for Lapland Longspur (Calcarius lapponicus) and Semipalmated Sandpiper (Calidris pusilla) north of Baker Lake, Nunavut. I found and monitored nests over multiple breeding seasons and used pitfall traps and conducted vegetation surveys. Results show that elevation significantly affects arthropod biomass and nest placement, but not nest initiation or success. Both species preferentially nested at lower elevations with higher arthropod biomass. Thus, birds in the central Arctic choose nesting sites at lower elevations with better food availability rather than higher elevations with earlier snowmelt.

Author Keywords: Arctic, arthropod biomass, Lapland Longspur, nest site selection, nest success, Semipalmated Sandpiper

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

Office workers consistently report greater productivity in the workplace when standing compared to sitting (Chambers et al., 2019; MacEwan et al., 2015; Mantzari et al., 2018). In contrast, laboratory studies report inconsistent evidence that posture (sitting vs. standing) affects cognitive performance, usually operationalized as selective attention (Caron et al., 2020; 2022; Rosenbaum et al., 2017; Smith et al., 2019). The present work assessed whether the discrepancy between workplace and laboratory findings is because workplace tasks are more difficult than the tasks used in laboratory research. Three visual search experiments are reported. Search difficulty was increased in Experiments 1 and 2 and posture difficulty was increased in Experiment 3. There was no evidence that posture affected attention in any of the experiments suggesting that the failure to find an effect of posture on attention in previous work was not due to the task difficulty.

Author Keywords: Cognition, Cognitive Resources, Dual Task, Embodied Cognition, Posture, Selective Attention

This thesis aimed to explore students' perspectives on university exams in two studies. Using a phenomenological approach, Study 1 recruited 10 senior undergraduate students to participate in semi-structured interviews. A thematic analysis revealed key themes related to exam purpose, effectiveness, fairness, and emotional responses. These insights informed the development of a sequence model explaining how students form exam perceptions. Study 2 was a concurrent, embedded, correlational mixed-methods case study of sophomore Psychology students' (N = 35) experiences with a case-based take-home exam designed according to motivational design principles. Findings from this study highlight the associations between students' motivation orientation and motivational assessment features and students' positive experiences and perceptions of the exam. This thesis offers an informative framework for instructors aiming to promote student buy-in, while also meeting course learning outcomes and facilitating deeper engagement with assessments.

Author Keywords: alternative assessment, assessment design, learning outcomes, student motivation, university exams

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

Chromophoric dissolved organic matter (CDOM), a chemically diverse family of organic compounds defined by their ability to absorb ultraviolet and visible light, is a critical constituent of numerous environmental systems, including freshwater lakes. Industrial operations in the Athabasca Oil Sands Region (AOSR, Alberta, Canada) are major sources of acidic inorganic gases and organic contaminants to the atmosphere, the subsequent deposition of which posed the potential to alter the composition of natural CDOM within surrounding lake surface-waters. The objective of this thesis was to determine if OS sources measurably impacted CDOM quality within 50 regionally monitored acid sensitive lakes by means of a) altered acid-base chemical processes or b) industrial atmospheric CDOM inputs. Ultraviolet-visible light spectroscopy and excitation emission matrix (EEM) fluorescence spectroscopy were applied to characterize CDOM within regional lake surface-waters to identify the primary sources (e.g., natural, anthropogenic) and process (e.g., acid-base chemistry) influencing chromophoric organic matter quality. These spectroscopic techniques were further used to evaluate industrial CDOM within atmospheric aerosols and deposition to assist with the identification of industrial CDOM within lake waters. Spectroscopic analysis of regional lake surface-water found weak associations between CDOM and acid-base variables, suggesting that acid inputs from OS sources would have limited influence over surface-water chromophoric organic matter. A distinct fluorescent component (i.e., fluorophore) measured within the lake samples (C3) displayed decreasing emission intensity as a function of distance from OS sources and positive correlations with surface-water polycyclic aromatic compounds, implying industrial influence. Spectral similarity between C3 and industrial fluorophores observed from regional aerosol and atmospheric deposition samples further confirmed the lake fluorophore was linked to OS sources. This research suggests that EEM fluorescence spectroscopy could be used as a cost-effective technique to detect industrial pollution within lake surface-waters throughout the AOSR.

Author Keywords: atmospheric brown carbon, atmospheric deposition, atmospheric pollution, dissolved organic matter, fluorescence spectroscopy, lake chemistry