Graduate Theses & Dissertations

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Forensic Epistemology
Forensic epistemology is the study of knowledge as it relates to forensic science and can be broken into four sources; intuitive, authoritative, logical and empirical. In a four-phase research approach, I explored reasoning skills (logical knowledge) used by crime scene experts and methods (empirical knowledge) for forensic case-specific experimentation. First, the reasoning skills of crime scene investigators (CSI) and bloodstain pattern analysts (BPA) were tested, correlated to demographics and reasoning categories were compared. Practitioner’s with graduate level education performed better on the reasoning test, however, significant differences were not found between test scores and years of experience. Similarly, there was no difference between test scores and employment status (specifically, police or civilian employees), for the CSI group nor within the BPA group. This information suggests that level of education plays the most important role in the development and use of reasoning skills, whereas experience and employment status are not as influential. Second, I investigate potential strategies in selecting data types for case-specific experimentation in pattern-interpretation disciplines within forensic science. I also examined the epistemic status of practitioner case experimentation in forensic science. Practitioners were more confident in a mixed-method approach when conducting case-specific experimentation. In addition, there is a knowledge gap in experimental design for some forensic practitioners. Third, is a reprint of the introductory section of my published book entitled The Scientific Method in Forensic Science: A Canadian Handbook that abridges knowledge gained from this dissertation with further evidence-based literature review and experiential examples. This phase summarizes the scientific method in forensic science and provides guidance for forensic science students and practitioners. The final phase merges the findings from the primary studies with a literature review; offering scientific evidence supporting suggested research and pedagogic strategies that can help increase the epistemic status of forensic science. Author Keywords: case-specific research, epistemology, forensic science, hypothetico-deductive reasoning, logic, research models
Range dynamics of two closely related felids
Species ranges are changing and the rate at which the climate is warming is faster than anything previously seen in the past, consequently species will need to adapt quickly, track the climate or perish. Cold adapted terrestrial species are the most vulnerable, because they are limited by the availability of land at the cold edge of their range. This means that many alpine, boreal and polar species essentially have nowhere to go as the climate warms. Habitat generalists are widely distributed across the globe and are highly adaptable to anthropogenic change. Our future biodiversity may only consist of several habitat generalists. The Canada lynx (Lynx canadensis) is a boreal species that has limited range expansion potential at the cold end of its range and its range has already contracted by 40%. The lynx has nowhere to go as climate warming progresses in this current century. Therefore, understanding the causes of its range contraction could enlighten us on conservation and management strategies that we might undertake as climate warms. My analyses indicated that the Canada lynx seems to have tracked the habitat that it is adapted to in more northern homogenous boreal forests and the bobcat (Lynx rufus), a habitat generalist, has simply replaced it in the south. Author Keywords: Anthropogenic Change, Competition, Connectivity, Lynx canadensis, Lynx rufus, Range change
White-Tailed Fear
The primary method used to maintain white-tailed deer (Odocoileus virginianus) populations at densities that are ecologically, economically, socially, and culturally sustainable is hunter harvest. This method considers only the removal of animals from the population (the direct effect) and does not conventionally consider the costs imposed on deer as they adopt hunter avoidance strategies (the risk effect). The impact of risk effects on prey can exceed that of direct effects and there is interest in applying this concept to wildlife management. Deer are potential candidates as they have demonstrated behavioural responses to hunters. I explored the potential of such a management practice by quantifying how human decisions around hunting create a landscape of fear for deer and how deer alter their space use and behaviour in response. I used a social survey to explore the attitudes of rural landowners in southern and eastern Ontario towards deer and deer hunting to understand why landowners limited hunting on their property. I used GPS tracking devices to quantify habitat selection by hunters and hunting dogs (Canis familiaris) to better understand the distribution of hunting effort across the landscape. I used GPS collars to quantify the habitat selection of deer as they responded to this hunting pressure. I used trail cameras to quantify a fine-scale behavioural response, vigilance, by deer in areas with and without hunting. Human actions created a highly heterogeneous landscape of fear for deer. Landowner decisions excluded hunters from over half of the rural and exurban landscape in southern and eastern Ontario, a pattern predicted by landowner hunting participation and not landcover composition. Hunter decisions on whether to hunt with or without dogs resulted in dramatically different distributions of hunting effort across the landscape. Deer showed a high degree of behavioural plasticity and, rather than adopting uniform hunter avoidance strategies, tailored their response to the local conditions. The incorporation of risk effects into white-tailed deer management is feasible and could be done by capitalizing on a better understanding of deer behaviour to improve current management practices or by designing targeted hunting practices to elicit a landscape of fear with specific management objectives. Author Keywords: Brownian bridge movement models, hunting, landscape of fear, resource utilization functions, risk effects, white-tailed deer
Novel Aliphatic Amides from Vegetable Oils as Bio-Based Phase Change Materials
Energy storage efficiency and sustainability require advanced technologies and novel materials. Recently, bio-based phase change materials (PCMs) have received significant attention for thermal energy storage (TES) uses. Vegetable oils are versatile renewable feedstocks that are well suited for the development of sustainable, functional PCMs. PCMs derived from vegetable oil, which compares favorably with paraffin waxes, the industry standard, are currently available. However, their melting points are typically below 80 °C preventing their wider integration in TES applications, particularly those requiring higher temperatures. The present work manipulated the structural building blocks of fatty acids to advantageously affect the intermolecular forces and increase the properties relevant to TES. The polar amide functional group was incorporated into fatty moieties to take advantage of the strong hydrogen bonds that it forms to increase intermolecular attractions and hence increase the phase change temperature and enthalpy as well as to improve thermal stability and thermal conductivity. A series of carefully designed lipid-derived monoamides and four series of lipid-derived diamides were synthesized via benign and simple amidation reactions. The purity of the amides and the intermolecular hydrogen bond strength were assessed using 1H NMR and FTIR. The properties relevant to TES such as thermal transition, crystal structure and polymorphism, thermal stability and thermal conductivity were measured using DSC, XRD, TGA and a thermal conductivity analyzer, respectively. The complex roles of the PCM’s constituting molecular building blocks in the phase behavior were elucidated and correlations between structure, processing conditions and macroscopic physicochemical properties, never before elucidated, were assembled in predictive relationships, drawing a unified picture of the rules that generally govern the phase behavior of lipid-derived PCMs. Practically, the prepared amides demonstrated desirable TES properties with substantial performance improvement over current bio-based PCMs. They presented increased phase change temperatures (79 - 159 °C), enthalpies of fusion (155 - 220 J/g) and thermal stability (234 - 353 °C). More importantly, the predictive structure-function relationships established in this work will allow the straightforward engineering of lipid-derived amide PCM architectures with judicious selection of molecular building blocks to extend the range of organic PCMs and deliver thermal properties desirable for TES applications. Author Keywords: LATENT HEAT THERMAL ENERGY STORAGE, LIPID-DERIVED AMIDES, PHASE CHANGE MATERIALS, RENEWABLE, SOLID LIQUID AMIDE PCMS, THERMAL PROPERTIES
Icelandic Dust Entrainment, Emission & Deposition
Extremely active dust sources within selected areas of Iceland that are comprised of particles supplied from both glacio-fluvial outwash systems and volcanic eruptions (Bullard et al., 2016; Gassó et al., 2018). The supply of sediments, sparsity of vegetation, high frequency of surface winds, and lack of adequate gravel pavement to reduce sand drifting are believed to influence the duration, frequency, and magnitude of these dust events in Iceland. Apart from recent collaborative efforts to measure and model dust entrainment, emission and deposition (Prospero et al., 2012; Zwaaftink et al., 2017), several underlying physical mechanisms that are unique to cold, humid climates and the geology of Iceland are not well understood. This study specifically aims to assess and understand the physics of Icelandic dust entrainment and deposition with an emphasis on the influence of climate and the physical characteristics of the particles. A series of laboratory experiments of different configurations were carried out on several sediments collected from some of the most emissive sources in Iceland in order to understand these dust processes. The results from this study show that the increasing particle sphericity is associated with progressively smaller particle size; and an abundance of amorphous glass increases the surface area and roughness of the particles, which contributes to high porosity that alters the particle skeletal density. The particle features and climate are interlinked with the entrainment and deposition rates. For instance, coarse sediments emit higher PM concentrations than sediments containing more clay. The strong wind shear at the bed surface acts to disperse many of the tiny particle aggregates and coated liquid droplets contained within a splash structure created by the impact of a single water droplet. The deposition of suspended dust particulates is dependent on the particle characteristics and relative humidity. The retreat of glaciers and ice-cap masses in Iceland are expected to expose new dust particulate sources as the global mean temperature continues to rise (Cannone et al., 2008; Radic and Hock, 2011). Therefore, the influence of the particle characteristics and climate on the dust entrainment, emission and de- position must be accounted for in the parameterization of dust dispersion models related to suspended volcaniclastic particles. Author Keywords: High latitude cold climate environments, Icelandic dust particle characteristics, Laser Doppler anemometer, Rain droplet impact, Settling velocity, Wind tunnel
Assessing Measured and Perceived Risks to Drinking Water Sources
Microcontaminants originating from wastewater effluent and run-off from agricultural lands may be present in the sources of drinking water for rural and Indigenous communities in mixed-use watersheds. In this study, a convergent parallel mixed-methods design was applied to assess measured and perceived risks of contamination in the sources of drinking water for two communities; the Six Nations of the Grand River community in Ontario and the community of Soufriere in St. Lucia, West Indies. The overall goal of the project was to assess how measured and perceived risks of exposure to chemical and biological contaminants in drinking water sources could inform water management strategies for the communities. Quantitative data obtained from the analysis of water samples collected indicated that the highest levels and occurrence of fecal bacteria were found in the Soufriere watershed while the highest concentrations and occurrence of pesticides were found in the Grand River watershed. In the Grand River watershed, conventional treatment of water followed by activated carbon filtration and UV disinfection removed fecal bacteria and also removed many chemical microcontaminants with efficiencies as high as 98%. Data from both watersheds indicated that there was a strong positive correlation between the levels of caffeine and sucralose (i.e. indicators of wastewater contamination) in water samples and the levels of either Total Coliforms or fecal bacteria of human origin. Human health risk assessments of individual pesticides and pesticide mixtures performed by applying a hazard quotient (HQ) and hazard index (HI) model, respectively indicated that there were no apparent risks to human health from those microcontaminants. Qualitative data obtained from face-to-face interviews with water managers and health professionals working in the two communities, which were collected and analysed concurrently but independently, illustrated that there were cross-cultural similarities and differences in factors influencing the perceptions of risks associated with the sources of drinking water. These perceptions of risks were mainly influenced by factors such as heuristics or informal and informal reasoning, cognitive-affective factors, social-political institutions and cultural factors. These factors may have also influenced water managers and health professionals, as they often recommended more “soft” strategies for managing water resources in the communities. Key words: pesticides, fecal bacteria, microcontaminants, POCIS, measured risks, perceived risks, water management, First Nations, Grand River, Soufriere, St. Lucia Author Keywords: fecal bacteria, measured risks, microcontaminants, perceived risks, POCIS, water management
Reconnecting the Heart and Spirit
This research explores key themes emerging from the question of the meaning Anishinaabe individuals attach to utilizing traditional practices and ceremonies to address their own trauma. The contributors share their stories, which are deeply rooted in relationships. The methodology of this research is also rooted within an Indigenous paradigm; storytelling is a core feature of relationships and knowledge transmission through its ability to weave together and across generations. Indigenous cultures have had a long history of both verbal and visual storytelling, in the forms of pictographs and petroglyphs, wampum belts, bead and quill work, and so on. While stories are often entertaining, they are at their core, the most human of activities. Anishinaabe approaches to ceremony, spirit and the sacred are woven into the language, attitudes and practices that people still engage in, despite the depredations of colonization. The findings of this research explore how identity, found through love, caring, self-awareness, and the (re)claiming of wellness and wholeness, permeates the stories of healing and is rooted in ceremonies. This is relationship with self and self-in-relation to all things: niwiikaniginaa. Land-as-home, culture, family, and love ground people in their sense of self and wellness. Language and thought emerge from the land, the source of well-being or mino bimaadsiwin in the most profound ways. It is through home – land, family, culture, spiritual connection – that healing occurs in ways that cannot be found in clinical systems. Author Keywords: Colonization, First Nations, Healing, Identity, Storytelling, Trauma
Population Dynamics of Eastern Coyotes in Southeastern Ontario
The ability of animal populations to compensate for harvest mortality provides the basis for sustainable harvesting. Coyote populations are resilient to exploitation, but the underlying mechanisms of compensation and how they inter-relate are not fully understood. Moreover, deficiencies in the quality and quantity of information about eastern coyotes preclude effective management. I combined field work, laboratory work, and genetic profiling to investigate the population dynamics of eastern coyotes in southeastern Ontario. Specifically, I conducted research on coyotes during 2010–2013 in Prince Edward County where coyote hunting and trapping seasons were open all year. First, I investigated their social status dynamics and space-use patterns. Transients exhibited extensive space-use relative to residents, potentially encountering vacant territories and/or breeding positions, and some transients became residents, potentially filling vacant territories and/or breeding positions. Accordingly, the study population demonstrated the potential to compensate for harvest mortality via source-sink dynamics and/or buffering reproductive capacity. Second, I investigated their survival and cause-specific mortality. Residents exhibited greater survival than transients, probably partly because of the benefits of holding a territory, and transients seemingly exhibited greater vulnerability to harvest than residents, probably partly because their movements exposed them to greater cumulative mortality risks over time. Accordingly, harvest mortality disproportionately impacted the non-reproductive segment of the study population and thus may have failed to substantially limit reproduction, and thus recruitment. Third, I investigated their reproduction and breeding histories. Females in the study population exhibited age-specific reproductive rates and litter sizes generally typical of those in exploited coyote populations. Accordingly, increased reproductive rates and increased litter sizes may have offset losses due to harvest mortality. There was at least some breeder turnover in the study population due to harvest mortality, but many breeders survived to reproduce for multiple years and those that died were quickly replaced. My findings have important management implications for eastern coyotes and contribute significantly to better understanding of their resilience to harvest. Indiscriminate killing of coyotes through liberal harvest is unlikely to be effective in reducing their abundance. Management strategies should consider non-lethal alternatives and/or targeted lethal control for dealing with problem coyotes. Author Keywords: Canis latrans var., eastern coyotes, population dynamics, Prince Edward County, southeastern Ontario
collaborative ecotoxicological risk assessment of in-place pollutants in Owen Sound Bay, Lake Huron within the Saugeen Ojibway Nation Territory
Owen Sound Bay, which is located within the traditional territory of the Saugeen Ojibway Nation (SON), is contaminated as a result of historical industrial and shipping activity. Gross contamination of the sediments in the inner part of the Bay (i.e., Owen Sound Harbour) includes high concentrations of polycyclic aromatic hydrocarbons (PAHs) and other organic compounds, as well as metals that may pose a risk to the SON fishery for lake whitefish (Coregonus clupeaformis). However, evaluating the environmental risks posed by contaminated sediments is a challenge, as these risks are dependent upon several factors and require multiple lines of evidence. Including Indigenous communities in environmental risk assessment and the management of those risks is vital for sustaining ecosystem integrity, as well as respecting Treaty Rights. In this study, a risk assessment framework was developed that included several risk assessment tools used in Western science and also encompassed the concerns and values of the SON, including the application of SON-ecological knowledge. Methods for risk evaluation included gathering lines of evidence though community workshops, as well as field sampling in the Bay to determine the concentrations of PAHs and other organic contaminants in sediments and in the water column. Laboratory studies of toxicity to early life stages of lake whitefish and Japanese medaka (Oryzias latipes) and sediment disturbance simulations to evaluate biological responses in juvenile lake whitefish were also completed as lines of evidence. The results indicate that leaving the harbour “as is” without a thorough analysis of remediation options fails to address the concerns of the people within the SON communities. Overall, this research demonstrated a successful process for developing a collaborative risk assessment framework that recognizes the sovereignty of Indigenous peoples and promotes Nation-to-Nation decision making. Author Keywords: biomarkers, Coregonus clupeaformis, Indigenous knowledge, polycyclic aromatic hydrocarbons, risk assessment, source tracking
Biogeography of Carabidae (Coleoptera) in the Boreal forest
Basic biogeographic information is lacking for many species, such as where species are found, and how they dispersed there. Using ground beetles collected during 2008-2015 from across northern Ontario and Akimiski Island, Nunavut, I present new information on ground beetle distribution in this eastern Nearctic boreal forest, including 2 first Canadian records, 9 first provincial and 48 first territorial records, as well as 74 new records that extend the known range of many large and common ground beetles several hundred kilometres. I used these distributions to redress the knowledge gap that includes fundamental distribution data, i.e. the Wallacean shortfall, and to inform later chapters in my thesis.In Chapter 3, I examine the range expansion pattern of Carabus granulatus, a non-native species, as it spread across northeastern North America and I provide a new range record. Northern Ontario is already under threat from non-native species entering the region and it is important to conduct studies in the region before more disturbance associated with development occurs. In Chapter 4, I examine the hypothesis that northern Ontario effectively acts as a climate plateau for poikilotherms, using the predictions from Bergmann's rule as my metric. The body length of ground beetles does not appear to change over the small temperature gradient that exists across northern Ontario latitudes, supporting the climate plateau hypothesis. In Chapter 5, I test hypotheses about dispersal mechanisms that contributed to post glacial re-establishment of ground beetles using predictions of geographic distribution patterns as metrics. I found that ground beetles were likely carried downstream by rivers which aided their dispersal northward from southern refugia. I infer from the current geographic distributions that flightless ground beetle species are still expanding their range in this boreal region. Finally, I argue that there is an urgent need for more basic research on species distributions while it is still possible in regions like northern Ontario, before increased industrial and agricultural development, and expanding resource extraction projects obliterate evidence of historic ecological processes. Author Keywords: Boreal forest, Carabidae, Coleoptera, Passive dispersal, Post-glacial distribution, Range extension
Untitled (dissertation 4.2)
Untitled (dissertation 4.2) offers a performative take on the political implications of digital archives. I argue that technological developments and their increasing ubiquity has not resulted in more reliable archives; it has facilitated the exacerbation of what Jacques Derrida calls mal d’archive—or archive fever—which refers to the institutionally supported passion to preserve that is perpetually threatened by the inevitably of loss. A performative perspective, specifically derived from the work of contemporary performance theorists and artists, affords a contemporary archival practice that not only accepts, but is informed by mal d’archive because it shifts the focus from what is preserved to how it has become and continues to be preservable through archival acts. This is important in our contemporary moment because the ubiquity of digital technologies has exacerbated the symptoms of mal d’archive: a rapid increase in both the formal and informal production of preservable content, and consequently, as Derrida reminds us, archival violence. Untitled (dissertation 4.2) also includes a performative engagement with mal d’archive through two interludes. The first interlude features what I am calling “glitch-utterances,” which refers to the visual representations of technological mishaps. The documents in the second interlude—an iteration of the exhibition catalogue that resulted from my 2020 artist residency at the Art Gallery of Peterborough—engage with the productive function of the archive because they performatively constitute the exhibition as having happened regardless of whether or not it actually occurred, which, significantly, it did not. I conclude Untitled (dissertation 4.2) with a look at the ecological impact of digital archives—perhaps an “ecological fever.” It is not my intention to offer a solution for this “ecological fever,” nor address its full impact. My aim is to conclude this dissertation with a supplement of sorts: a look at the ecological impact of digital archives because I feel it is irresponsible not to given their increasing ubiquity. With this in mind, the glitch-utterances featured in both interludes can perform an important role in calling attention to the technological materialities and computational processes that are rendered invisible by Big Tech companies via metaphors—the ethereal Cloud metaphor, for example. These glitch-utterances point to the very material substrates that support the virtual, and can thus act as an important reminder of the ecological consequences of digital archives, which, like archival practices, are tied to institutional agendas. Author Keywords: Archive , Curation , Digital Archive, Documentation, Multimedia performance, Performativity
Composition and Transformation of Dissolved Organic Matter in Hudson Bay, Canada
The Hudson Bay region is a sensitive environment, where anthropogenic (e.g., dams, diversions, and/or reservoirs) impacts have increased in recent decades, potentially influencing the functioning of the ecosystem. Dissolved organic matter (DOM) entering Hudson Bay comes from both terrestrial (allochthonous) and aquatic (autochthonous) sources. The chemical composition of DOM is important, as it controls carbon biogeochemistry, nutrient cycling, and heat exchange. In rivers, estuaries, and oceans, photochemical processes and microbial degradation play a significant role in the chemical composition of DOM. Yet, our knowledge is scarce into how photochemical and microbial processes effect DOM composition specifically in Arctic aquatic systems making it difficult to predict how the carbon cycle will respond to a changing environment. This Ph.D. thesis addresses: (1) the composition of photochemically altered autochthonous and allochthonous DOM; (2) the photochemical transformations of DOM in surface waters of Hudson Bay; and (3) the microbial transformations of DOM in Hudson Bay surface waters. Using multiple analytical techniques, this work demonstrated that photochemical and microbial effects were different for light absorbing DOM compounds and ionisable DOM analyzed by Fourier transform-ion cyclotron-resonance-mass spectrometry (FT-ICR-MS). Based on FT-ICR-MS analysis, microbial processes had a greater impact on the molecular composition of allochthonous DOM originating from riverine sources and estuary whereas photochemical processes were the dominant mechanism for degradation of autochthonous DOM in Hudson Bay. Photochemical processes significantly decreased colored dissolved organic matter (CDOM) and fluorescence dissolved organic matter (FDOM) loss whereas microbial degradation was minimal in Hudson Bay river, estuary, and coastal waters. The results of this thesis highlight the importance of photochemical and microbial alteration of DOM in Arctic regions, two processes that are expected to be enhanced under climate change conditions. Author Keywords: Carbon cycle, Field flow fractionation, Microbial transformation, Optical properties, Photochemical degradation

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Graduate student theses produced at Trent University. You may also browse theses and dissertations by year, program, or author.

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