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This thesis is focused on studying the population dynamics of a predator-prey system in a patchy environment, taking anti-predation responses into consideration. Firstly, we conduct mathematical analysis on the equilibrium solutions of the system. Using techniques from calculus we show that particular steady state solutions exist when the parameters of the system meet certain criteria. We then show that a further set of conditions leads to the local stability of these solutions. The second step is to extend the existing mathematical analysis by way of numerical simulations. We use octave to confirm the previous results, as well as to show that more complicated dynamics can exist, such as stable oscillations. We consider more complex and meaningful functions for nonlinear dispersal between patches and nonlinear predation, and show that the proposed model exhibits behaviours we expect to see in a population model.

Author Keywords: Anti-predation response, Asymptotic stability, Dispersal, Patch model, Population dynamics, Predator-prey

AbstractOral Language and the Approximate Number System – A Preliminary Study Janice Shewen The approximate number system (ANS) involves the processing of rudimentary quantity and is thought to be an innate developmental building block for mathematics and its sister construct, the symbolic system. The conventional belief is that the ANS is language independent; however, this notion is questioned and explored in the current study, which represents a preliminary investigation into the concurrent and longitudinal relations between different aspects of oral language and the ANS in 4-year-old children and one year later when they were 5. A sample of 26 children (13 boys;13 girls) with average intelligence completed standardized measures of oral language and verbal memory, and a computerized quantity discrimination task that required children to accurately discern between two visually presented quantities. Correlational analysis showed concurrent and longitudinal relations between different aspects of language and quantity discrimination. This suggests that different aspects of language predict quantity discrimination over a one-year period and challenge the current and accepted theory that the ANS is a language independent system. The findings also have implications for early childhood education – avenues to strengthen a child's ANS via targeted oral language instruction, curricula, and subsequent provision of experiences. The findings also support early oral language screening to monitor or provide opportunities for improving quantity approximation skills. This early intervention could impact later symbolic processing and mathematic success. Keywords: Non-symbolic system, approximate number system, quantity discrimination, symbolic system, oral language, morphology, syntax, semantics, relational concepts.

Author Keywords: Approximate Number System, Non-symbolic system, oral language, quantity discrimination, symbolic system

Coherent anti-Stokes Raman scattering (CARS) microscopy is a label-free chemical imaging modality that uses CARS as a contrast mechanism to spatially resolve materials based on their molecular vibrational spectra. Due to the presence of a non resonant background that obfuscates the chemical information contained in CARS spectra, CARS images suffer from poor contrast and cannot be readily used for quantitative chemical analysis. Over the past two decades, spectral retrieval methods have been developed to obtain Raman-like spectra from CARS spectra. These methods promise to improve image contrast and enable reliable quantitative analysis. In this work I systematically evaluate a selection of the forefront spectral retrieval methods, including both analytical and machine learning approaches, to determine how well they perform at the task of non resonant background removal. The more recent machine learning methods demonstrate remarkable performance on spectra resembling the training dataset but are not as suitable as the analytical methods in general. The analytical methods based on the discrete Hilbert transform thus remain preferable due to their ease-of-use and general applicability.

Author Keywords: chemical imaging, coherent anti-stokes raman scattering, kramers-kronig analysis, machine learning, non-resonant background, spectral phase retrieval

This thesis employs zooarchaeological, taphonomic, and spatial analysis to reconstruct subsistence behaviors of Middle Paleolithic Neanderthals using layer V of Abric del Pastor as a case study. Located in Alcoy, Alicante, Spain, Abric del Pastor is a cave shelter with occupation layers dated from MIS 5 through 3. The faunal assemblage is examined on two time scales: i) a longer time frame focused on large scale human occupation and use and ii) another, shorter time frame in an attempt to distinguish possible shorter anthropogenic events. The layer V assemblage is comprised of at least two occupation events, Occupation A and Occupation B. These are two relatively well-preserved anthropogenic accumulations dominated by medium sized taxa. In these occupations, the carcasses were likely transported from a separate kill site to the cave shelter to be processed and consumed. The taxonomic and taphonomic patterns uncovered in these occupation events are similar suggesting consistent behavioral patterns throughout Layer V. Ultimately, the faunal assemblage is typical of other MIS 5-3 rock shelters in the Iberian Peninsula. By examining the subsistence practices of layer V, dated to MIS 4, this work aims to fill a gap in the MIS 4 Iberian Peninsula literature and add to the conversation on how early hominins adapted to the changing climate.

Author Keywords: Abric del Pastor, Iberian Peninsula, Middle Paleolithic, Palimpsest, Time Perspectivism, Zooarchaeology

A key knowledge gap in aeolian transport research concerns the adjustment of saltation processes to the extreme conditions found within high-latitude regions. A series of wind tunnel experiments were carried out under full climate control and over a wide range in humidity. Particle entrainment and transport within shearing flows of varied wind speed were monitored over beds of varied temperature, and ice content to determine their affect on 1) particle trajectory, 2) saltation cloud height, 3) particle velocity, 4) surface erosivity, 5) mass transport rate and 6) vertical dust flux. Particles were found to have higher velocities over cold beds than dry beds. With a 3% increase in bed moisture content, a significant increase in particle velocity was measured. Fewer particles are ejected from a bed with moisture than a dry bed. The mass transport rate was measured to be 23% higher at -10 degrees Celsius compared to 30 degrees Celsius.

Author Keywords: Aeolian processes

Previous researchers have linked lower levels of stress and greater ability to mobilize energy toward a goal (self-motivation); confidence in their ability to complete/achieve a particular task or goal (self-efficacy), and ability to willfully control their thoughts, emotions and behaviour (self-control) to regular physical activity (PA). In an effort to provide further insight into the processes underlying regular PA researches have begun to explore the interplay among stress and multiple self-regulatory variables when predicting level of PA (i.e., intensity and duration). In line with this integrated approach the present study aimed to examine the interplay among self-motivation, self-efficacy, and self-control when predicting daily PA. The study was a correlational design with cross-sectional data on trait self-motivation and self-efficacy collected at baseline, and longitudinal data collected on stress, PA, state self-control, self-motivation and self-efficacy over a 2 day period. The results from the regression model (n = 418) revealed a negative indirect effect of stress on participants level of PA through its negative relationship with state multifactor self-regulation. This mediation effect appeared to be moderated by trait SE and SM. In conclusion, these results support the notion of a stress related depletion effect acting on individuals state self-regulatory resources which was associated with lower levels of PA (i.e. intensity and duration). However, the negative effect of stress appeared to be buffered by high levels of trait SE and SM.

Author Keywords: exercise, physical activity, self-control, self-efficacy, self-motivation, self-regulation

Lake whitefish (Coregonus clupeaformis) are ecologically, economically, and culturally significant across their range, yet little is documented about the species' spawning behaviour. Recruitment of lake whitefish has dramatically declined over the past two decades across many regions of the Laurentian Great Lakes, most notably in lakes Huron and Michigan, prompting research efforts to fill critical knowledge gaps in the life history of this species. Understanding the reproductive ecology of lake whitefish, including documenting aspects of spawning behaviour, may reveal clues about factors contributing to the declines. This study used fine-scale acoustic telemetry to characterize sex-specific movement patterns and habitat associations of lake whitefish during the spawning season. A VEMCO Positioning System (VPS) was deployed at an active spawning shoal in Georgian Bay (Lake Huron), with guidance provided by Saugeen Ojibway Nation members with local ecological knowledge about the shoal and the lake whitefish population. In the fall of 2020, 50 lake whitefish were captured and tagged at the spawning shoal; 28 of those fish were observed the following spawning season in 2021. A clear increase and decrease was observed in the presence of individuals in the study area over the spawning period. Both sexes moved into shallower waters at night and deeper waters during the day at rates of 0.162 m/h and 0.08 m/h, respectively. Decreased rates of movement and horizontal distance travelled were detected during the day leading up to a peak activity phase where 22 fish were present. At night during this peak activity phase, males moved 30.0% faster on average than females (0.204 ± 0.13 and 0.143 ± 0.10 m/s, respectively). This study provided a unique opportunity to work with local First Nations to understand lake whitefish spawning behaviour, providing insights into the reproductive ecology of a population undergoing concerning declines in recruitment and abundance.

Author Keywords: Coregonine restoration, Coregonus clupeaformis, Fine-scale acoustic telemetry, GLATOS, Spawning habitat, Two-Eyed Seeing

Naphthenic acids are a major contaminant of concern and a focus of much research around remediation of oil sand process affected waters, OSPW. Using activated carbon adsorbents are an attractive option given their low cost of fabrication and implementation. A deeper evaluation of the effect naphthenic acid structural differences have on uptake affinity is warranted. In this thesis an in-depth exploration of naphthenic acid adsorption onto activated carbon is provided including many more model naphthenic acid species than what have been assessed previously in adsorption studies. Both adsorption kinetics and isotherms at the relevant alkaline pH of OSPW using several different carbon adsorbents with pH buffering to simulate the behaviour of real OSPW were evaluated. Given the time sensitive application of most adsorbents towards treating contaminated waters such as OSPW, achieving fast adsorption rates for model naphthenic acids is an important goal worth considering. Textural properties of activated carbon most conducive for fast adsorption kinetics were assessed using several candidate model species. Clear evidence is presented, demonstrating the influence of both the pore size distribution and particle size of porous adsorbents on uptake rates of naphthenic acids, demonstrating that careful optimization of these adsorbent properties can result in adequate uptake rates. Adsorption isotherms were used to assess model naphthenic acid affinity towards activated carbon. Uptake for the model naphthenic acids varied considerably regardless of the activated carbon used, ranging from 350 mg g-1 to near zero highlighting recalcitrant species. The equilibrium data was explored to identify important structural features of these species and key physiochemical properties that influence adsorption. It was demonstrated that certain naphthenic acids are resistant to adsorption when hydrophobic adsorbents are used. Adsorption isotherm modelling helped explore interactions occurring at the interface between naphthenic acids and adsorbent surfaces. Naphthenic acid hydrophobicity was identified as an importance physiochemical property for achieving high adsorption capacities onto activated carbon. Evidence is also presented that indicates favorable hydrogen bonding between naphthenic acids and surface site hydroxyl groups, demonstrating the importance of adsorbent surface functionality for naphthenic acid uptake. The adsorption mechanism was further explored through use of a thermodynamic analysis of the model naphthenic acid system using activated carbon. Standard state enthalpy and isosteric enthalpy of adsorption values were used to further support the proposed mechanisms occurring between model species and activated carbons. This research highlights the challenges associated with removing naphthenic acids from OSPW through adsorption and identifies how adsorbent surface chemistry modification will need to be used to increase the removal efficiency of recalcitrant naphthenic acid species when using activated carbon.

Author Keywords: Activated Carbon, Isotherms, Kinetics, Modelling, Naphthenic Acids, Thermodynamics

This thesis comprises two parts:Part I describes a method to improve the accuracy with which the polarization state of light can be characterized by the rotating quarter-wave plate technique. Through detailed analysis, verified by experiment, we determine the positions of the optic axes of the retarder and linear polarizer, and the wave plate retardance, to better than 1° for typical signal-to-noise ratios. Accurate determination of the Stokes parameters can be achieved using this technique to determine the precise retardance at each of the wavelengths of interest. In Part II, a theoretical analysis of the Fabry-Perot interferometer and its application to quantitative absorption spectroscopy is presented. Specifically the effects of broadening due to non-monochromatic light sources and examples of non-ideal etalon surfaces on the visibility of absorption features are investigated. The potential of this type of spectrometer for ethanol detection in a portable breath analysis application is discussed.

Author Keywords: ABSORPTION SPECTROSCOPY, CALIBRATION, FABRY-PEROT INTERFEROMETER, OPTICS, POLARIMETRY

The Great Lakes represent nearly a fifth of the global freshwater surface supply, and support culturally, economically, and ecologically important fish species such as Walleye (Sander vitreus). With water temperatures projected to rise by several degrees in the coming century, understanding the energetic impacts on fishes is crucial for effective habitat and fisheries management. I measured the swimming performance, accelerometer-based activity, and metabolism of walleye in relation to body size, sex, and water temperature to assess potential responses to climate variability. Both acceleration and swim speed predicted metabolic rate with reasonable accuracy. Temperature had a positive effect on oxygen consumption whereas body mass had a negative effect. Critical swimming speed increased with temperature, and tailbeat frequency had positive relationships with swim speed and acceleration. My laboratory-based calibrations should enable remote field monitoring of energy use of walleye (via accelerometers) and help conserve an important species through bioenergetic modelling.

Author Keywords: accelerometry, bioenergetics, climate change, metabolism, respirometry, walleye