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Sex-specific genetic structure is a commonly observed pattern among vertebrate species. Facing differential selective pressures, individuals may adopt sex-specific life historical traits that ultimately shape genetic variation among populations. Although differential dispersal dynamics are commonly detected in the literature, few studies have investigated the potential effect of sex-specific functional connectivity on genetic structure. The recent uses of Graph Theory in landscape genetics have demonstrated network capacities to describe complex system behaviors where network topology intuitively represents genetic interaction among sub-units. By implementing a sex-specific network approach, our results suggest that Sex-Specific Graphs (SSG) are sensitive to differential male and female dispersal dynamics of a fisher (Martes pennanti) metapopulation in southern Ontario. Our analyses based on SSG topologies supported the hypothesis of male-biased dispersal. Furthermore, we demonstrated that the effect of the landscape, identified at the population-level, could be partitioned among sex-specific strata. We found that female connectivity was negatively affected by snow depth, while being neutral for males. Our findings underlined the potential of conducting sex-specific analysis by identifying landscape elements that promotes or impedes functional connectivity of wildlife populations, which sometimes remains cryptic when studied at the population level. We propose that SSG approach would be applicable to other vagile species where differential sex-specific processes are expected to occur.

Author Keywords: genetic structure, Landscape Genetics, Martes pennanti, Population Graph, sex-biased dispersal, Sex-Specific Graphs

The epoxides of oligomeric self-metathesized soybean oil (MSBO) and cross-metathesized palm oil (PMTAG) and canola oil (CMTAG) containing terminal double bonds were used to produce nonisocyanate polyurethanes (NIPUs) as well as anhydride, amine and thiol-cured epoxies.

The synthesized NIPUs displayed metal adhesive properties for CMTAG and MSBO with MSBO being favoured probably due to its plasticizing nature as opposed to CMTAG. The relationship was reversed for the anhydride curing reaction where it was found that CMTAG, due to its lower degree of plasticizing content from the reduced dangling chains, produced higher tensile strengths than MSBO. Both MSBO and CMTAG led to fully cured amine and thiol products that were sticky gels, which prevented physical analyzses of their expected solidified products. PMTAG, due to its low number of reactive groups, was not suitable for the synthesis of these polymers.

Author Keywords: Amine-cured epoxy, Anhydride-cured epoxy, Metathesis, Nonisocyanate Polyurethanes, Thiol-cured epoxy

Past research suggests that taking a process oriented approach, setting clear and concrete goals, and using both conscious planning and proactive coping are the best methods to be successful with goal pursuit. Also the literature has found that individuals scoring higher in general resourcefulness tend to be more successful at achieving goals than their less resourceful counterparts. My thesis looked at these goal pursuit behaviours under the lens of resourcefulness using a mixed methods approach. After completing Rosenbaum's self-control scale (1980) assessing general resourcefulness, participants took part in a semi-structured interview asking them about a recent goal they had set and how they dealt with interfering obstacles. The hope was hearing differences about how highly and less resourceful people discuss their goals and setbacks would give a deeper understanding about the characteristics of success. The themes emerging from the interviews were: blame and excuses versus understanding and growth, internal versus external factors, living in the moment versus conscious planning and magical versus realistic thinking. In contrast to low-scoring participants, highly resourceful individuals grew from their setbacks, were internally driven, consciously planned, and thought realistically about their goals. Less resourceful individual, on the other hand blamed outside factors and made excuses, were only motivated externally, didn't plan out their goals and believed their goals would just magically materialize over time. My discussion focuses on the ability to train lower resourceful individuals over longer interventions, and the applications of understanding and using resourcefulness as a lens in future studies.

Author Keywords: Goal, Habits, Quitting, Resourcefulness, Self-Control, Success

Micropollutants are discharged into the aquatic environment with industrial and domestic wastewater and these compounds may cause toxic effects in aquatic organisms. In this study, the toxic effects to fish of micropollutants extracted from ozonated and nonozonated municipal wastewater effluent (MWWE) were measured in order to assess the effectiveness of ozonation in reducing toxicity. Juvenile rainbow trout (Oncorhynchus mykiss) injected with extracts prepared from ozonated MWWE had significantly reduced induction of plasma vitellogenin (VTG), significantly reduced hepatic total glutathione (tGSH) levels and an elevated oxidized-to-total glutathione (GSSG-to-tGSH) ratio. Exposure of Japanese medaka (Oryzias latipes) embryos to extracts prepared from both ozonated and non-ozonated MWWE resulted in elevated developmental toxicity in both treatment groups. These results indicate that wastewater treatment by ozonation reduces the estrogenicity of wastewater, but treatment may induce oxidative stress and embryonic developmental toxicity due to the production of toxic by-products.

Author Keywords: Estrogenicity, Micropollutants, Oxidative stress, Ozonation, Toxic by-products, Wastewater

Despite being an essential nutrient at trace levels, selenium can be devastating to aquatic environments when present in excess. There is no apparent correlation between total aqueous selenium concentrations and observed toxic effects because bioaccumulation varies over several orders of magnitude depending on the chemical species of selenium and the biological species present in the lowest trophic level of the aquatic food chain. Despite being used in toxicity models due to its high bioavailability, free selenomethionine had not been found previously in the environment outside of a biological entity. Here, it is confirmed that selenomethionine is produced during the biological treatment of selenium-contaminated wastewater, and released in the effluent along with other discrete organic selenium species, including selenomethionine oxide.

This identification followed the development of a rigorous preconcentration and cleanup procedure, allowing for the analysis of these organic selenium species in high-ionic strength matrices. A newly optimized anion-exchange chromatographic separation was coupled to inductively-coupled plasma mass spectrometry for the simultaneous quantification of these organic selenium species along with the more ubiquitous selenium oxyanions, selenite and selenate. This separation method was also coupled to electrospray tandem mass spectrometry for structural confirmation of selenomethionine and selenomethionine oxide. High resolution orbitrap mass spectrometry was used to identify another oxidation product of selenomethionine – a cyclic species which was tentatively identified, by coelution, in a selenium-contaminated river water sample. The production and release of selenomethionine, selenomethionine oxide, Se-(methyl) selenocysteine, and methyl selenic acid were observed for various laboratory algal cultures.

Once the presence of free selenomethionine in a water system was confirmed, factors affecting its uptake into algal cultures were examined. The uptake of selenomethionine into Scenedesmus obliquus was noted to be significantly higher under low nitrate conditions, where it was incorporated into selenium-containing proteins more readily than at higher nitrate conditions where other metabolites were produced. With the increasing popularity of biological treatment systems for the remediation of selenium-contaminated waters, these observations, combined with existing knowledge, could be used to make predictions regarding the potential toxicity of selenium in various environmental scenarios.

Author Keywords: bioremediation, electrospray mass spectrometry, inductively-coupled plasma mass spectrometry, selenium, selenoamino acids, selenomethionine

Arctic terrestrial ecosystems have experienced substantial structural and compositional changes in response to warming climate in recent decades, especially the expansion of shrub species in Arctic tundra. Climatic and vegetation changes could feedback to the global climate by changing the carbon balance of Arctic tundra. The objective of this thesis was to investigate the influence of increased shrub coverage on carbon exchange processes between atmosphere and the Arctic tundra ecosystem. In this study a space-for-time substitution was used, referred to as a shrub expansion "chronosequence", with three sites along a natural gradient of deciduous shrub coverage in the Canadian low Arctic. Leaf-level photosynthetic capacity (Amax) of dominating birch shrub Betula glandulosa (Michx.) was significantly higher (P<0.05) at the site where shrubs were more abundant and taller than at the other sites. For all sites, mean Amax in 2014 was significantly lower than in 2013, in part potentially due to differences in precipitation distribution. Bulk soil respiration (RS) rate was significantly higher (P<0.05) at the site with more shrubs compared with the other sites. The differences in RS across sites appeared to be driven by differences in soil physiochemical properties, such as soil nitrogen and soil bulk density rather than soil microclimate factors (e.g. soil temperature, moisture). The three sites were either annual CO2 sources (NEP<0) to the atmosphere or CO2 neutral, with strongest annual CO2 sources (-44.1±7.0 g C m-2) at the site with most shrubs. Overall this study suggests that shrubs tundra carbon balance will change with shrub expansion and that shrub ecosystems in the Arctic currently act as annual carbon sources or neutral to the atmospheric CO2 and further shrub expansion might strengthen the CO2 emissions, causing a positive feedback to the warming climate.

Author Keywords: arctic tundra, carbon exchange, climate change, photosynthetic capacity, shrub expansion, soil respiration

This thesis provides an analysis of the Carnegie Commission's report on the causes and consequences of the Balkan Wars (1912-1913). Shortly after the closing of hostilities, the Carnegie Endowment for International Peace appointed an international Commission of Inquiry to collect evidence of atrocities from the sites of war. The thesis analyzes the arguments expressed in the Commission's report as an example of European and American attitudes towards the Balkans. The concept of Balkanism provides a theoretical framework according to which the Commissioners' views are contextualized within the existing stereotypes of the region. Based on the correspondence available in the archives of the Carnegie Endowment for International Peace, the memoirs and biographies of the various members of the Commission, and the information published in periodicals, this work also examines the justifications for the appointment of the Commission, the circumstances related to the investigation of atrocities and the reaction of Balkan governments to the report.

Keywords: Carnegie Report, Carnegie Commission, Carnegie Endowment for International Peace, Balkan Wars, Balkanism.

Author Keywords: Balkanism, Balkans, Balkan Wars, Carnegie Commission, Carnegie Endowment, Carnegie Report

During the 1970s, ideological divisions caused by divergent interpretations of the American failure in Vietnam permeated the world of foreign policymaking. This led to a concern among the architects of the Reagan administration that foreign policymaking had become incoherent. They attempted to mitigate the effects of this disharmony by re-establishing a workable degree of ideological conformity within the foreign policy bureaucracy. This thesis focuses on the strategy used to improve ideological conformity and its effect on the foreign policy bureaucracy's ability to produce well informed policy. Using case studies of two of Reagan's ambassadors to Central America, it argues that Reagan's strategy created a foreign policy bureaucracy that manufactured uninformed policy. The influence granted to officials who based their recommendations on regional expertise was severely curtailed. This shift produced a subsequent change in diplomatic practice, as foreign service officers adapted to the demand for allegiance to the president's agenda.

Author Keywords: American Foreign Policy, Central America, Ronald Reagan

Environmental variation can affect consumer trait expression and alter ecological and evolutionary dynamics in natural populations. However, although dietary nutrient content can vary by an order of magnitude in natural ecosystems, intra-specific differences in consumer responses to food quality have not been thoroughly investigated. Therefore, the purpose of my dissertation was to examine the influence of dietary nutrition and other environmental factors on consumer phenotypic variation using the freshwater cladoceran Daphnia. I conducted a series of complementary laboratory and field studies where I examined the effects of dietary phosphorus (P) content and additional biological/environmental variables (multi-elemental limitation, genetic variation, and temperature) on daphnid life-history, biochemistry, body elemental composition, and population growth. In general, phenotypic expression within a species varied significantly in response to all experimental variables, but the relative influence of each was highly context dependent. In my first chapter, I found that dietary P content and environmental calcium (Ca) concentrations both altered Daphnia body Ca:P ratios and growth rates of individuals and affected intrinsic rates of increase at the population level. However, food quality appeared to have a much larger effect on trait expression, and body Ca:P ratios were highly sensitive to other forms of dietary nutrient limitation. Next, I documented significant quantitative genetic variation and phenotypic plasticity in daphnid P content, growth, and P use efficiency of field collected animals grown across dietary P gradients. Trait expression was also influenced by genotype X diet interactions suggesting that consumer responses to dietary nutrient limitation can be heritable and may be adaptive in different nutrient environments. Finally, I found that temperature appeared to override food quality effects and decouple P metabolism in natural Daphnia populations, but total biomass production was affected by both dietary P content and temperature, depending on the nutrient content of the lake. Overall, my dissertation shows that consumer responses to nutrient limitation can vary significantly within a species and that changes in trait expression may be modified by other environmental variables. These results should be incorporated into existing stoichiometric models and used to investigate the eco-evolutionary consequences of consumer phenotypic variation in response to nutritional stress.

Author Keywords: ecological stoichiometry, evolution, life-history, nutrient limitation, nutrient metabolism, zooplankton

The flavohemoglobin in Giardia intestinalis (gFlHb) is the only known protozoan member of a protein class typically associated with detoxifying nitric oxide (by oxidation to nitrate) in bacteria and yeast. Mutants of the B10 tyrosine (Y30F) and E11 leucine (L58A), conserved residues thought to influence ligand binding, were expressed and studied using Resonance Raman (RR) spectroscopy. In the wild type protein, RR conducted using a carbon monoxide probe detects two distinct Fe-CO stretches associated with two different active site configurations. In the open configuration, CO does not interact with any polar side chains, while in the closed configuration, CO strongly interacts with one or more distal residues. Analysis of the Y30F mutant provided direct evidence of this tyrosine's role in ligand stabilization, as it had only a single Fe-CO stretching mode. This stretching mode was higher in energy than the open conformer of the wild type, indicating a residual hydrogen bonding interaction, likely provided by the E7 glutamine (Q54). In contrast the L58A mutant had no effect on the configurational nature of the enzyme. This was unexpected, as the side chain of L58 sits atop the heme and is thought to regulate the access of distal residues to the heme-bound ligand. The similar spectroscopic properties of wild type and L58A suggest that any such regulation would involve rapid conformational dynamics within the heme pocket.

Author Keywords: B10 Tyrosine, Catalytic Globin, E11 Leucine, Flavohemoglobin, gFlHb, Giardia intestinalis