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Assessing the population genetic structure of the endangered Cucumber tree (Magnolia acuminata) in southwestern Ontario using nuclear and chloroplast genetic markers.

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Creator (cre): Budd, Cara Emily, Thesis advisor (ths): Freeland, Joanna R, Degree committee member (dgc): Dorken, Marcel, Degree committee member (dgc): Crins, Bill, Degree granting institution (dgg): Trent University
Abstract:

Magnolia acuminata (Cucumber tree) is the only native Magnolia in Canada, where it is both federally and provincially listed as endangered.Magnolia acuminata in Canada can be found inhabiting pockets of Carolinian forest within Norfolk and Niagara regions of southwestern Ontario. Using a combination of nuclear and chloroplast markers, this study assessed the genetic diversity and differentiation of M. acuminata in Canada, compared to samples from the core distribution of this species across the United States. Analyses revealed evidence of barriers to dispersal and gene flow among Ontario populations, although genetic diversity remains high and is in fact comparable to levels of diversity estimated across the much broader range of M. acuminata in the USA. When examining temporal differences in genetic diversity, our study found that seedlings were far fewer than mature trees in Ontario, and in one site in particular, diversity was lower in seedlings than that of the adult trees. This study raises concern regarding the future viability of M. acuminata in Ontario, and conservation managers should factor in the need to maintain genetic diversity in young trees for the long-term sustainability of M. acuminata in Ontario.

Author Keywords: conservation genetics, cpDNA, forest fragmentation, Magnolia acuminata, microsatellites, population genetic structure

2014

Abject Utopianism and Psychic Space: An Exploration of a Psychological Progress Toward Utopia in the Work of Samuel R. Delany and Julia Kristeva

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Creator (cre): Ellis, Cameron Alexander James, Thesis advisor (ths): Hollinger, Veronica, Degree committee member (dgc): Eddy, Charmaine, Degree committee member (dgc): Panagia, Davide, Degree committee member (dgc): Stavro, Elaine, Degree committee member (dgc): Pero, Allan, Degree granting institution (dgg): Trent University
Abstract:

This dissertation utilizes the psychoanalytic theories of French psychoanalyst Julia Kristeva as a lens through which to read the novels of American author Samuel R. Delany. I argue that concepts proper to Kristeva's work--namely abjection and/or the abject--can provide a way to think what it might mean to be utopian in the 21st century. Delany's novels are received historically, which is to say his work speaks from a certain historical and cultural viewpoint that is not that of today; however, I claim that his novels are exceptional for their attempts to portray other ways of being in the world. Delany's novels, though, contain bodies, psychologies, and sexualities that are considered abject with respect to contemporary morality. Nonetheless, this dissertation argues that such manifestations of abject lived experience provide the groundwork for the possibility of thinking utopianism differently today. Throughout, what I am working toward is a notion that I call Abject Utopianism: Rather than direct attention toward those sites that closely, yet imperfectly, approximate the ideal, one should commit one's attention to those sights that others avoid, abscond, or turn their nose up at in disgust, for those are the sites of hope for a better world today.

Author Keywords: Abject, Delany, Kristeva, Literary Criticism, Psychoanalysis, Utopia

2014

The Commonality of Enemies: Carlism and anarchism in modern Spain, 1868-1937

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Creator (cre): Martin, Steven Henry, Thesis advisor (ths): Cazorla-Sanchez, Antonio, Degree committee member (dgc): Andriewsky, Olga, Degree committee member (dgc): Kay, Carolyn, Degree committee member (dgc): Shubert, Adrian, Degree granting institution (dgg): Trent University
Abstract:

Carlism and anarchism were revolutionary social movements that acquired significant popular support during the most intensive period of modernization in Spain (mid 19th to mid 20th centuries). It was noted but not well explored by contemporaries and historians that these enemies were similar in their hostility towards modernization and in their intense idealism. This thesis compares the two movements in order to determine the nature of their commonality and what this suggests about ideological enemies. A range of sources were consulted, including scholarship on modern Spain, biographical information on individuals who converted from Carlism to anarchism and contemporary print media. It was concluded that they were produced by the same destabilizing processes of disentailment and industrialization, which drew the working classes towards proposals that would have otherwise seemed implausibly utopian. The thesis further suggests that they were uniquely idealistic, in that they put moral integrity before the success of their cause.

Author Keywords: anarchism, Carlism, enemy other, modernization, Modern Spain, social movements

2014

TESTING THE ROLE OF BIMODAL CELLS IN NEAR-HAND EFFECTS: AN rTMS STUDY

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Creator (cre): Beben, Karolina, Thesis advisor (ths): Brown, Liana E, Degree committee member (dgc): Lehmann, Hugo, Degree committee member (dgc): Henriques, Denise Y. P, Degree granting institution (dgg): Trent University
Abstract:

We investigated whether hand-proximity effects arise from the recruitment of visual-tactile bimodal cells. In Experiment 1, we executed right-hand open-loop reaching movements to targets, presented either near or far from the resting left-hand, and after applying repetitive transcranial magnetic stimulation (rTMS) to suppress neuronal activity in the PMd and AIP, in Experiment 2. Results from Experiment 1, indicated that near-hand targets improved accuracy and reduced variability. In Experiment 2, suppressing PMd showed similar near-hand effects as above. In contrast, applying rTMS to AIP disrupted the representation of target location, indicating less accuracy and greater error. Near-hand proximity effects possibly arise from the recruitment of visual-tactile bimodal cells within the human AIP.

Author Keywords: anterior intraparietal sulcus, peripersonal space, repetitive transcranial magnetic stimulation (rTMS), , rTMS, anterior intraparietal sulcus, AIP., visual-tactile bimodal neurons

2015

Nymphs, Satyrs and Impotent Old Men

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Creator (cre): Shore, Deborah Ann, Thesis advisor (ths): Siena, Kevin P, Degree committee member (dgc): Andrew, Donna T, Degree committee member (dgc): Hurl-Eamon, Jennine, Degree committee member (dgc): Miron, Janet, Degree granting institution (dgg): Trent University
Abstract:

British pornographic texts arguing the texts were part of a wider cultural discourse on luxury, criticising the upper echelons of society for their decadent and vice-ridden lifestyles. Pornographic texts consistently portray the elites of Britain as partaking in sexual deviances including lesbianism, sex with dolls, dildos and household objects. The portrayals could be dismissed as tales fabricated for the titillation of the reading audience except that medical texts of the period diagnose the diseases of nymphomania and satyriasis, the rough equivalent of modern sexual addiction, as primarily affecting those of the upper class. Lifestyle was the key to diagnosis; luxurious living was thought to weaken the elite body rendering it vulnerable to excess sexual passions. Therefore, the hyper-sexual elite in pornographic texts reflected the contemporary cultural understandings of lifestyle and physiology.

Author Keywords: Britain, culture, eighteenth century, nymphomania, pornography, sexuality

2014

Childhood diet and feeding practices at Apollonia: Evidence from deciduous dental pathology and stable isotope analysis.

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Creator (cre): Schmidt, Jodi Lee, Thesis advisor (ths): Keenleyside, Anne, Degree committee member (dgc): Williams, Jocelyn, Degree committee member (dgc): Conolly, James, Degree committee member (dgc): Garvie-Lok, Sandra, Degree granting institution (dgg): Trent University
Abstract:

This study analyses deciduous dental pathology and stable carbon and nitrogen isotopes to investigate the relationship between dietary composition, feeding practices, and oral health in a subadult skeletal sample from the Greek colonial site of Apollonia Pontica, Bulgaria (5th to 3rd century BC). Stable isotope analysis of 74 bone collagen samples indicates that weaning began between the ages of 6 months and 1 year, and was complete by the age of 4. The stable isotope data are consistent with a diet of primarily terrestrial C3 resources. The deciduous dentitions of 85 individuals aged between 8.5 months and 10.5 years were examined for evidence of a number of pathological conditions. The presence of dental caries, calculus, occlusal tooth wear and an abscess indicate that foods introduced early in life affected the oral health of these individuals. Overall, the deciduous dental data correlate well with the stable isotope data and ancient textual sources regarding infant and childhood dietary composition and feeding practices.

Author Keywords: breastfeeding, deciduous dentition, dental pathology, stable carbon and nitrogen isotopes, weaning

2014

Selection on functional genes across a flying squirrel (genus Glaucomys) hybrid zone

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Creator (cre): Lalor, Jillian L., Thesis advisor (ths): Bowman, Jeff, Thesis advisor (ths): Wilson, Paul J, Degree committee member (dgc): Schulte-Hostedde, Albrecht, Degree committee member (dgc): Murray, Dennis, Degree granting institution (dgg): Trent University
Abstract:

While hybridization between distinct taxa can have undesirable implications, it can also result in increased genetic variability and potentially, the exchange of adaptive genes or traits. Adaptive variation acquired through introgressive hybridization may be particularly advantageous for species facing rapid environmental change. I investigated a novel, climate change-induced hybrid zone between two flying squirrel species: the southern (Glaucomys volans) and northern (G. sabrinus) flying squirrel. I was interested in the occurrence of hybridization and introgression, the type of selective pressures maintaining the hybrid zone and the potential for adaptive introgression. I found relatively low hybridization and introgression frequencies (1.7% and 2.9% of the population, respectively) and no evidence of selection on hybrids or backcrosses in particular environments. I conclude that the data are more consistent with a hybrid zone maintained by endogenous (environment-independent) selection. I tested for adaptive introgression using two functional genes: IGF-1 and CLOCK. I documented intermediate functional allele frequencies in backcrosses compared to parental populations, suggesting the alleles do not confer fitness advantages in backcrosses. Despite lack of evidence for current adaptive introgression, genetic admixture between G. volans and G. sabrinus may provide adaptive potential should these species face more rapid or drastic environmental change in the future.

Author Keywords: adaptive introgression, flying squirrel, Glaucomys sabrinus, Glaucomys volans, hybridization, introgression

2014

MOVEMENT PARAMETERS AND SPACE USE FOR THE SOUTHERN HUDSON BAY POLAR BEAR SUBPOPULATION IN THE FACE OF A CHANGING CLIMATE

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Creator (cre): Middel, Kevin Robert, Thesis advisor (ths): Obbard, Martyn E, Degree committee member (dgc): Pond, Bruce A, Degree committee member (dgc): Schaefer, James A, Degree granting institution (dgg): Trent University
Abstract:

Changes to the Arctic and sub-Arctic climate are becoming increasingly evident as it warms faster than other areas of the globe, supporting evidence that predictions of future warming will be amplified due to positive feedback mechanisms. The Southern Hudson Bay polar bear (Ursus maritimus) subpopulation is one of the most southerly subpopulations in the world, putting it at increased risk due to effects of climate change. Whereas many other subpopulations have been the subject of intense research and monitoring, little research has been completed detailing the movement behaviour and space use of bears within Southern Hudson Bay. I used detailed movement data collected on female polar bears to establish a baseline of movement information for this subpopulation to which future work can be compared and effects of climate change can be assessed I evaluated the use of core areas during critical periods of the year (breeding and ice breakup) and evaluated common space use as a means of assessing site fidelity during the breeding season. Movement rates and home range sizes were comparable to those of the neighbouring Western Hudson Bay subpopulation. I also found evidence of increased occurrences of long distance, late fall movements along the coast to the northwest, presumably to gain earlier access to first ice. Though space use analysis did not reveal evidence of site fidelity to specific breeding areas in Hudson Bay, I found that core use areas are at risk of substantially shortened ice duration (x¯ =76 days shorter) using projected ice data based on the high emissions A2 climate change scenario.

Author Keywords: climate change, Hudson Bay, movement, polar bear, sea ice, utilization distribution

2014

Habitat use and community structure of grassland birds in southern Ontario agro-ecosystems.

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Creator (cre): McGuire, Sarah Lauren, Thesis advisor (ths): Nocera, Joe J., Degree committee member (dgc): Schaefer, Jim, Degree committee member (dgc): Burke, Dawn, Degree granting institution (dgg): Trent University
Abstract:

Most grassland bird populations are in decline, so it is becoming increasingly important to understand how they use agricultural field types and form their communities. I performed point counts in cultural meadow, intensive agriculture, and non-intensive agriculture areas in 2011 and 2012. Generalized linear models were used to determine the habitat relationships of six focal species. I found that non-intensive agriculture was used most often and intensive agriculture was often avoided, but there were exceptions which indicate habitat use can be species-specific. I determined in which habitats competition was likely occurring and which species pairs were competing in 2011. In 2012, I experimentally tested these relationships by introducing artificial competitors onto sites. By comparing presence-absence data from 2011 to 2012, I found evidence of habitat-mediated interspecific and conspecific attraction involving Bobolink and Grasshopper Sparrow. This research contributes to the current understanding of grassland bird community ecology and conservation.

Author Keywords: agriculture, BACI, community ecology, habitat use, species at risk, species interactions

2014

Anthropogenic particles and microplastics in headwater lake catchments in Muskoka-Haliburton, Canada

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Creator (cre): Welsh, Brittany, Thesis advisor (ths): Aherne, Julian, Degree granting institution (dgg): Trent University
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Microplastics, plastic particles less than 5 mm in diameter, are ubiquitous in the environment. This study estimated the abundance of microplastics (MP) in atmospheric deposition from four background monitoring stations in Muskoka-Haliburton, south-central Ontario, Canada and quantified the fate of microplastics to three background headwater lake catchments in Muskoka-Haliburton. Microplastics were observed across all sample media with polyethylene terephthalate and polyamide being predominant. The average atmospheric deposition of anthropogenic particles was 57 particles/m2/day with a plastic deposition rate of 7 MP/m2/day. Atmospheric deposition represented the highest daily microplastic flux rate to the three headwater lake catchments compared, 1.5 to 4 times greater than the flux rate for the inflow streams suggesting that atmospheric deposition can account for all the inflowing microplastics. A large fraction of the microplastics from atmospheric deposition (41 – 73%) were retained in the terrestrial catchment and there was a high retention of microplastics in each of the study lakes (1.44 – 7.39 million MP/day; 30 – 45%) suggesting that a large fraction of the terrestrial catchment export is retained by the lakes and that lakes are a reservoir for microplastics.

Author Keywords: Atmospheric deposition, Microplastics, Ontario, Plastic pollution, Sinks, Sources

2022