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The Holocene Climate Optimum turned the Gobi Desert from a mainly grassland habitat into a mosaic landscape composed of dune-fields, wetlands and high elevation forests (Janz 2012, 2016; Janz et al. 2017). The populations that inhabited the region at the time adapted by adopting new settlement patterns and tools, which might have allowed them to better exploit a new wide range of resources (Janz 2012, 2016; Janz et al. 2017). This thesis investigates the emergence of ground stone tool technology in the Gobi Desert and its connection with wild plant use by foragers at the time. Twenty-one implements were studied through experimental, use-wear and residue analysis. The results reveal that the tools were used to process several categories of wild plants. By conducting this investigation in legacy collections, this study also proved that archaeological micro-botanical evidence can be recovered from such materials and that their contamination can be assessed through specific protocols.

Author Keywords: Gobi Desert;, Ground Stone Tools;, Macro-lithics;, Mongolia;, Neolithic;, Northeast Asia;

In Ontario, farmers commonly use a MZ (Maize (Zea mays L.))-SB (Soybean (Glycine max))/WW (Winter wheat (Triticum aestivum)) – CC (mixed cover crop) rotation to maximize economic benefits. This study aimed to investigate the short-term impacts of the crop rotation phases and their associated management practices in this diversified cash crop rotation on soil health and the abundance of nitrogen (N)-cycling soil microbial communities (SMCs). Additionally, the abundance of N-cycling SMCs and plant-available N in both surface (0-5 cm) and rooting zone (5-15 cm) depths were characterized in tile-drained (TD) and non-TD fields. In the present study, soils collected under the CC phase had the highest labile carbon levels (10-17% higher) and water-stable aggregates (35-50% higher) compared to the other two crop phases. Lower nitrifying (amoA) gene abundances and soil NO3--N levels were observed in the CC phase compared to the MZ and SB-WW phases, suggesting a potential for decreased nitrification in the CC phase. The presence of SB potentially influenced the soil N concentration in the subsequent WW phase likely due to the release of symbiotically fixed N in the SB-WW phase. Further, higher amoA abundances and NO3--N in the SB-WW phase imply a potential for increased nitrification in the SB-WW phase. Additionally, higher amoA/nosZI and nirS+nirK/nosZI ratios were observed in the MZ phase than in SB-WW and CC phases, suggesting a potential capacity for increased N2O emissions from the reactions mediated by N-cycling SMCs in soils planted to MZ during fall sampling days. In the TD and NTD field study, higher NO3--N levels were observed in TD-SB-WW fields at 5-15 cm vs. 0-5 cm depths, which was possibly facilitated by tile drainage. The TD-CC fields displayed higher nosZI gene abundances and lower nirS+nirK/nosZI abundance ratios, suggesting a greater potential capacity for decreased N2O emissions in soils planted to CCs during the spring sampling days. When examining changes in plant available N by soil depth, reduced downward movement of NO3- through shallow soil depths (0-15 cm depth) was observed in the CC phase compared to cash crops. This short-term study highlights the potential contribution of the CC phase, particularly within TD agricultural fields, for improving soil health and reducing potential N2O emissions. Together, these results suggest that management-associated differences in crop rotation phases have temporary effects on soil health and the abundance of SMCs. Future studies linking N-cycling SMC's potential activity and field-scale N2O fluxes will provide a better insight into the longer-term sustainability of Ontario's cash crop management systems.

Author Keywords: denitrification, maize-soybean-winter wheat- cover crop rotation, nitrification, soil depth, Sustainable agriculture, tile-drainage

In an effort to improve upon existing analytical methods, electrochemical sensors offer portable, cost-effective alternatives to traditional lab-based techniques. Recent advances in supramolecular chemistry offer a unique alternative to achieve high selectivity while also benefitting from facile scaling for mass production. Thus, by incorporating host-guest chemistry with electrochemical sensors, the development of simple and selective sensors is possible. To that extent, novel hosts and electroactive ion pairs were investigated for their ability to transduce an electrochemical signal representative of host-guest complexation. Results demonstrated that the upper rim modifications of resorcinarene hosts attenuated their affinity for electroactive probes whilst maintaining structural integrity upon extended cycling. Further work revealed that guests may be directly quantified via their complexation with electroactive hosts. The sensing method was further validated by quantification of surfactant pollutants in the Otonabee River. Through a fundamental understanding of the electrochemical behaviour of host-guest systems a general sensing platform can be developed, where hosts are interchangeable for specificity towards any desired analyte. Therefore, moving away from expensive lab-based methods and significantly reducing the barriers for biological or environmental monitoring.

Author Keywords: Electrochemistry, Ferrocene, Host-Guest, Resorcinarenes, Supramolecular Chemistry, Surfactants

The detection of ciguatoxins (CTXs) in biological samples is challenging due to their low concentrations, the presence of various congeners, and the absence of standardized methods. This study uses high resolution mass spectrometry (HRMS) with P-CTX-3B as a reference standard. The protonated molecules ([M+H]+) were most prevalent, especially when acetonitrile/water was utilized, providing enhanced sensitivity. Optimized collision energies of 15 eV for protonated molecules and flow rates of 10 µl/min enhance sensitivity and peak intensities, respectively. Acetonitrile/water (ACN/H2O) is recommended as the primary solvent for HRMS method, an aspect underexplored in existing literature. The detection of CTX-3B in fish tissue samples proved to be challenging, caused by variations in ion peak intensities and matrix effects, requiring a deeper exploration of the impact of complex matrices on CTX detection. The study emphasizes the need for a reliable internal standard to mitigate these effects and highlights the ongoing challenge of developing a rapid, simple, and sensitive detection method. The study's specific focus on the P-CTX-3B analogue significantly contributes to methodology development for this congener, serving as a foundational step in understanding and detecting CTX. Despite notable progress, the study acknowledges the absence of an ideal assay, outlining key challenges for future research on ciguatera analysis. It underscores the continuous necessity for method reevaluation, testing, and the broader goal of establishing a more clarified and rugged method for the identification of CTX in fish.

Author Keywords: Analytical Chemistry, Ciguatera Fish Poisoning, Ciguatoxin, High-Resolution Mass Spectrometry, Optimization, P-CTX-3B

Molecular and genomic tools provide a deeper understanding of the ecology and evolution of species and their capacity to adapt to changing selective pressures, where diversity is presumedly linked to higher fitness and evolutionary potential. Molecular tools can also illustrate how historical processes affect contemporary genetic variation to predict how current population trends may influence future genetic diversity. Genomic investigations increasingly extend beyond variation within host genomes to include diversity of their associated microbiomes, recognized to influence host/environment interactions and adaptation. Muskoxen (Ovibos moschatus) are iconic, Arctic herbivores of ecological, economic, and cultural significance. Demographically, most mainland muskox populations have remained stable or grown over the last century, yet the biggest herds, found on Victoria and Banks Islands (Nunavut and the Northwest Territories, Canada) have experienced recent and drastic population declines. These Arctic island population declines have been associated with warming trends leading to shifting ranges of forage biodiversity, and pathogen expansions directly associated with increased mortality. Genomic investigations have the potential to enhance understanding of these contrasting trends and the adaptive capacities of muskox to cope with rapid ecological change. In this thesis, I assess genetic, genomic, microbiome and diet diversity to better understand the ecology, and evolution of muskoxen. I found extremely low levels of genetic variation associated with population bottlenecks coinciding with major glaciation events and contemporarily low levels of gene flow among populations. Whole genome analyses identified signatures of selection between muskox populations, providing a genetic basis for the divergence of two previously proposed muskox subspecies. Significant differences in diversity, effective population size and inbreeding among subspecies suggests animals from Arctic islands and Greenland are more vulnerable to environmental change. Molecular investigations of diet and microbiome diversity reflected unique capacities of muskoxen to survive on high-fiber forage and exploit shifts in Arctic vegetation that may include continued shrubification. Overall, these data provide insight into the complex relationship between genetic diversity and changing environments, setting a foundation for expanded future investigations of muskox seeking to promote the future viability of this species.

Author Keywords: Genetic Diversity, Genome Assembly, Metabarcoding, Microsatellites, Muskox, Persistence

Cytokinins (CKs) are adenine derivative molecules that are present in all kingdoms of life. CKs are known to have a role in cell growth and development in plants. However, the role of CKs in vertebrate systems is not well understood. Frog virus 3 (FV3) is a type species of the Iridioviridae family, genus Ranavirus. FV3 is a major contributor to the amphibian population decline in North America. In this study, we demonstrate that concurrent and pretreatment of 20 µM of either N6-isopentyldenine (iP), N6-ispoentyladenosine (iPR), N6-furfurladenine/kinetin, and N6-furfurladenosine/kinetin riboside (KR) decreased FV3 replication. To understand the mechanism of inhibition, we assessed morphological changes in host cell nuclei to assess the effect of CKs on infected nuclei. Our results show that infection with FV3 and 20µM treatment of iP or iPR reduced nuclei size. These results are the first to reveal insight into the potential mechanism in which FV3 replication is inhibited by iP and iPR.  

Author Keywords: cytokinins, frog virus 3

An athlete's psychological response to a sports-related concussion may influence thesuccess of recovery and return to play. This exploratory study explored how athletes psychologically respond to concussion, using Acceptance and Commitment Therapy to examine the role of psychological flexibility in recovery and return to play. Thirty athletes who experienced a concussion in the past three months completed online surveys measuring symptom severity, sport confidence, psychological strain, anxiety, depression, and psychological flexibility. Depression significantly predicted symptom severity (β = .615, p = .015). Psychological flexibility improved from pre- to post-return to play (p = 0.032, d = 0.45) and was correlated with greater confidence (pre: r = –0.451; post: r = – 0.577) and lower psychological strain (r = 0.471). These findings suggest that increasing psychological flexibility may enhance recovery by reducing distress and building confidence. Return-to-play protocols should include psychological recovery measures.

Author Keywords: Concussion, Injury Recovery, Psychological Flexibility, Return to Play

This thesis investigates the tensions, gaps and opportunities presented by outdoor play-based learning. Written by a founder of the Forest School concept in Canada, this exploration revolves around two research questions: How can we (re)conceptualize outdoor play-based learning in formal education for children aged 0-8, and how can we integrate and reinvigorate both pedagogical theory and practice to support educators in embedding outdoor playful learning practices?

The research methodology applies autobiographical experience and conceptual frameworks to historical and current pedagogical theory, in an anti-oppressive and feminist research orientation that challenges received notions of what "counts" as knowledge (Brown & Strega, 2005, p. 6) – much in the same way that play challenges truisms about what constitutes education.

Key findings include situating outdoor play-based learning within the theoretical landscape, understanding outdoor play-based learning as an emerging current of environmental education, defining a set of core principles for outdoor play-based learning, and re-examining the role of the educator.

Author Keywords: Early Learning, Pedagogy, Play, Play-Based Learning, Playful Pedagogies, Risky Play

Estimation of population abundance from samples has inherent practical challenges. Moreover, analytical methods to estimate abundance may vary in statistical assumptions and prediction uncertainties. I evaluated the performance of design-based and model-based methods to estimate Canada geese (Branta canadensis) abundance based on aerial fixed-width transect surveys in the Hudson Bay Lowlands, Canada. I evaluated Empirical Bayesian Kriging (EBK), areal interpolation and a ratio estimator on the basis of accuracy and precision using spatial point simulations. Untransformed EBK was the most accurate and precise, due in part, to its inherent handling of nonstationary distributions. The ratio estimator followed the same trends as EBK and, in some cases, had higher precision. Consideration of alternative analytical methods and their strengths and weaknesses is an important step in generating reliable information for population monitoring. Geostatistical approaches such as EBK have the benefit of providing spatially explicit mapping of abundance and reliable population estimates.

Author Keywords: Areal interpolation, Design-based inference, Empirical Bayesian Kriging, Geostatistics, Model-based inference, Ratio estimator

Nikawiy narratives including Mother to daughter, nation to nation, spirit and intent, and Treaty Enforcement are based on nikawiy (my mother's) teachings that I interpret as my inherent role as Nehiyaw iskwew (Cree woman) specifically for governance and numbered Treaty Enforcement. My methodology 1is also based on nikawiy's Circle of Life, Pimatisiwin, Calendar (Poitras, 1996) curriculum that is related and included in the "universe is listening to me" paskwaw moostoos Treaty Law School (Poitras, 2016). We are from the Peepeekisis Cree Nation in what is now known as Saskatchewan. My mother osawastimahkoop iskwew is originally from Onion Lake on what is now the border between Alberta and Saskatchewan. Peepeekisis is in Treaty Four territory and Onion Lake is in Treaty Six territory.Is there a 'gap' for the role of Indian women and Nehiyawak Iskwew in the numbered Indian Treaty negotiations and generally in leadership? 2Though such a 'gap' may be said to be relatively common knowledge perhaps from the time of the treaty negotiations, a comprehensive and chronological review has yet to be produced that may address this. Treaty Four was entered into in 1874 and Treaty Six was entered into in 1876. Before this and in historical accounts, this gap may also be apparent and indicative of European/settler ethnocentrism based on white male research and documentation of this history.3 The colonial disruption of the Indian Residential School, in particular, would have also impacted oral transmission of any history including the role of women in the treaty negotiations that might also denote a role in governance and leadership. In a contemporary context now, the question for this role is the search for inherent foundations that may be identified as the base to contemporary governance and leadership frameworks for Nehiyaw Iskwewak (Cree women) in Treaty Four and Treaty Six.

1 Protocol has been offered to nikawiy to request her interpretation of "methodology' meaning.2 I could not find any written historical accounts for the role of Cree women during numbered Treaty negotiations. I know that, in general, there are few sources for Indian women in leadership, and particularly for any historical accounts of Indian women leadership. In Treaty Four and Treaty Six, there are no written accounts of Nehiyaw iskwew (Cree women) involvement in these treaty negotiations. The signatories to these treaties are documented as Nehiyaw napew (Cree men) only. Historical accounts document what Cree men leaders/Chiefs may have stated at this time. 3 A reason for the lack of any Cree women documentation in historical accounts of numbered Treaty negotiations is that there could be a lack of understanding for the role of Cree women by the European men who wrote these accounts. Generally, Europeans were coming from white patriarchal societies where women did not commonly have leadership roles.

Author Keywords: Calendar of Life, Cree