English

Mixtures of metals occur in surface waters, toxicity of which has drawn world-wide attention due to their crucial role in both ecotoxicology and regulations. The present research was undertaken to study the acute toxicity of binary mixtures of Ni, Cu, Zn, and Cd to the freshwater organism, Daphnia magna. The experimental approach included single and binary metal toxicity tests based on the 48h acute toxicity bioassay of Environment Canada. The acute toxicity of single metals followed the order of Cd > Cu > Zn > Ni. Based on the calculated 48h EC50 value of single metals, a toxic unit (TU) approach was used to combine two metals in a binary mixture, in which 1TU was equal to the 48h EC50 value of a metal in single exposure. The toxicity of binary metal mixtures to D. magna followed the order of Cu-Cd > Cu-Zn > Zn-Cd > Cu-Ni > Zn-Ni > Cd-Ni, which demonstrated three types of toxicity (i.e., less than additive, additive, and greater additive). Predictions from additivity models (including concentration addition (CA) and independent action (IA) models), a generalized linear model (GLM), and a biotic-ligand-like model (BLM-like) were compared to the bioassay results. The CA and the RA models also predicted three types of toxicity of the binary metal mixtures (i.e., less than additive, additive, and greater than additive). However, the CA model mostly overestimated the toxicity of binary mixtures. Predictions from the GLM supported the inclusion of the interaction between two metals in a mixture to predict the toxicity of binary metal mixtures. The binary metal toxicity was also predicted using a BLM-like model based on the calculated concentrations of free ionic forms of the metals, affinity constants, and toxic potency of each metal. In this model, it was hypothesized that the toxicity of metal mixture is the result of competition of metals with Ca2+ at biotic ligands, which can lead to whole-body deficiency of Ca2+ in D. magna. The BLM-like model provided the toxic potency of single metals with the following order, Cu > Cd > Zn > Ni. Although the prediction of the BLM-like model was not in good agreement with the observed toxicity of binary metal mixtures, an overestimation of risk of mixture toxicity was obtained using this model, which could be promising for use in environmental risk assessment.

Author Keywords: biotic ligand model, concentration addition, Daphnia magna, independent action, metal toxicity, modeling

This thesis investigates the similarities and differences between the tropical epicenters of South and Southeast Asia during the Charter State era, 800- 1400 CE. This study can inform scholars about the relationship between "people and place" by examining the ground plans, activities, and people associated with each epicenter. By using the comparative approach and entanglement theory, this study will examine the ancient states of Central and East Java, Dai Viet in North Vietnam, the Cham in Central Vietnam, the Chola of South India, and the Sinhalese of Sri Lanka. The ancient Maya of tropical Belize will be used as a cross-cultural comparator, which would not have had any contact with the other charter states. An extensive literature review and on-site visitations were necessary to provide the background and date to accomplish these goals. The results indicate striking similarities between tropical epicenters across the Charter States that developed out of the entanglements between humans and things. This thesis will help to further our understanding of tropical urbanism and the nature of epicenters in tropical environments.

Author Keywords: Anuradhapura, Caracol, Entanglement, Thang Long, Thanjavur, Urbanism

The goal of this thesis is to explore the role that civic (i.e. state-sponsored)

feasting and drinking played in early polis (pl. poleis), or city-state formation on Crete in

the Early Iron Age to Archaic transition, ca. 700-500 BCE. Using the two recently

excavated civic feasting structures at the site of Azoria as a model for both "inclusive"

and "exclusive" forms of civic feasting, this project compares and contrasts the role that it

played at a number of other sites in central and east Crete. In order to categorize the

structures as either inclusive or exclusive, all forms of published evidence were examined

including the buildings' architecture and the socially valued goods and ceramics found

within the structures. Ultimately, this project demonstrates that in the 8th century BCE,

inclusive feasting rituals and association with the past were used as means of creating and

maintaining a strong group identity, which paved the way for the use of more exclusive

practices in the 7th century BCE, where sub-group identities and alliances were formed

amongst members of the larger group. However, at the sites where there was evidence for

multiple civic feasting venues it appears that by the 7th century BCE, the interplay of both

inclusive and exclusive forms of feasting was crucial to the process of identity formation

for the citizens of these proto-poleis.

Author Keywords: Archaic Crete, Commensality, Feasting, Identity Formation, Polis formation

Distributing contextual fear episodes makes the memory become HPC-independent, meaning increasingly reliant on non-HPC memory structures. It is unclear, however, whether distribution of the conditioning episodes alone is sufficient or whether a combination of distribution and high conditioning saliency is necessary to make the memory become HPC-independent. To resolve this issue, rats were trained using a distributed contextual fear conditioning protocol in which foot-shocks were manipulated to create a low (0.4mA), intermediate (0.7 mA) and high (1.0 mA) saliency condition. This thesis also aimed to determine brain structures supporting the HPC-independent memory by assessing retention-induced c-fos expression in the basolateral- amygdala, perirhinal and anterior cingulate cortices. The results suggest that HPC lesion rats in the high saliency condition displayed similar level of freezing as control rats, indicating "strongly salient" and distributed episodes creates a HPC independent memory. c-fos expression suggests together, an increased context representation in the perirhinal and anterior cingulate cortices and a strengthened fear representation in the basolateral-amygdala supports the HPC-independent memory.

Author Keywords: context fear memory, distributed reinstatements, hippocampus, IEG, rat, saliency

Supercritical water (SCW) exhibits unique properties that differentiates it from its low temperature behaviour. Hydrogen bonding is dramatically reduced, there is no phase boundary between liquid and gaseous states, heat capacity increases, and there is a drastic reduction of the dielectric constant. Efforts are underway for researchers to harness these properties in the applications of power generation and hazardous waste destruction. However, the extreme environment created by the high temperatures, pressures and oxidizing capabilities pose unique challenges in terms of corrosion not present in subcritical water systems. Molecular Dynamics (MD) simulations have been used to obtain mass transport, hydration numbers and the influence on water structure of molecular oxygen, chloride, ammonia and iron (II) cations in corrosion crevices in an iron (II) hydroxide passivation layer. Solvation regimes marking the transitions of solvation based versus charge meditated processes were explored by locating the percolation thresholds of both physically and hydrogen bonded water clusters. A SCW flow through reactor was used to study hydrogen evolution rates over metal oxide surfaces, metal release rates and the kinetics for the oxidation of hydrogen gas by oxygen in SCW. Insights into corrosion phenomena are provided from the MD results as well as the experimental determination of flow reactor water and hydrogen chemistry.

Author Keywords: Flow Studies, Molecular Dynamics, Supercritical Water

This thesis elucidates the role of play and games—the ludic—in Julio Cortázar's novel Hopscotch (1966; translation of Rayuela, 1963) through a range of resonant theories. Literary gameplay dominates the formal, linguistic, affective, reflexive, and thematic dimensions of Hopscotch, which are analyzed through concepts borrowed from play theorist Roger Caillois, among others, and literary theorists including Mikhail Bakhtin and Wolfgang Iser, whose ludic theories of fiction begin to map the field of ludic fiction. The analysis positions Hopscotch as an exemplar of the ludic counter-tradition within the novel, a perennial tendency from Don Quixote to postmodernism and beyond. Hopscotch, like other ludic fictions, enacts a complex convergence of the ludic and the lucid. It provokes active reading over passive consumption, diminishes the hegemonic function of serious mimesis to elevate other forms of gameplay, notably chance, competition, vertigo, and enigma, to dominant positions, and ultimately demonstrates a profound affinity between play and critical consciousness.

Author Keywords: Bakhtin, Cortazar, Iser, Ludic, Novel, Play

While existing models of emotional intelligence (EI) generally recognize the importance of social competencies (SC), there is a tendency in the literature to narrow the focus to competencies that pertain to the self. Given the experiential and perceptual differences between self- vs. other-oriented emotional abilities, this is an important limitation of existing EI models and assessment tools. This thesis explores the psychometric properties of a multidimensional model for SC. Chapter 1 describes the evolution of work on SCs in modern psychology and describes the multidimensional model of SC under review. Chapter 2 replicates this model across a variety of samples and explores the model's construct validity via basic personality and EI constructs. Chapter 3 further explores the predictive validity of the SC measure within a group of project managers and several success and wellness variables. Chapter 4 examines potential applications for the model and suggestions for further research.

Author Keywords: emotional intelligence, project management, social competency, work readiness

This qualitative case study explored the experience of members and associates of

one university history department in order to examine the phenomena of choosing and

working within the history major in the context of current declines in humanities

enrolment. Drawing on interviews with 7 professors, 8 student majors, and 10

professional staff, it analyzed beliefs about how students should choose their majors,

benefits of historical thinking, the current climate of crisis in history, and resources to

support history students. Participants agreed that students should choose a major based on

intrinsic factors and shared a common vision of the meaning and importance of historical

thinking. However, participants experienced tension between these intrinsic values and

extrinsic pressures regarding the humanities crisis and the efficacy of student-support

resources. These results have implications for understanding pressures felt by current

humanities students and for developing new resources to better support history majors.

Author Keywords: case study, choice of major, historical thinking, history department, humanities crisis, student affairs

Seizures induce long-term changes in gene expression in the hippocampus. Experimental evidence has demonstrated a significant effect of epileptic activity on the activity of neurons that participate in complex cognitive and behavioural processes. The present series of experiments involving kindling with subconvulsive doses of PTZ demonstrates a link between seizures and altered immediate early gene expression within the hippocampus and dentate gyrus. In addition, newborn hippocampal neurons were shown to have decreased induction of plasticity-related genes, suggesting deficits in activity-dependent recruitment. These findings may shed light on the mechanisms underlying epileptogenesis and epilepsy-related hippocampal dysfunction in human patients.

Author Keywords: hippocampus, IEGs, kindling, neurogenesis, seizures

Wild populations are notoriously difficult to study due to confounding stochastic variables. This thesis tackles two components of investigating wild populations. The first examines the use of niche modeling to quantify macro-scale predator-prey relationships in canid populations across eastern North America, while the second examines range-wide molecular structure in Canada lynx. The goal of the first chapter is to quantify niche characteristics in a Canis hybrid zone of C. lupus, C. lycaon, and C. latrans to better understand the ecological differentiation of these species, and to assess the impacts of incorporating biotic interactions into species distribution models. The goal of the second chapter is to determine if DNA methylation, an epigenetic marker that modifies the structure of DNA, can be used to differentiate populations, and might be a signature of local adaptation. Our results indicated that canids across the hybrid zone in eastern North America exhibit low levels of genetic and ecological differentiation, and that the importance of biotic interactions are largely lost at large spatial scales. We also identified cryptic structure in methylation patterns in Canada lynx populations, which suggest signatures of local adaptation, and indicate the utility of DNA methylation as a marker for investigating adaptive divergence.

Author Keywords: Ecological Epigenetics, Ecological Genetics, SDM