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Climate change is resulting in ongoing temperature warming and increased frequencies of heatwaves. In aquatic ecosystems, temperature not only affects the distribution and abundance of phytoplankton, but warming may also be reducing the quantities of key nutrients produced by these important primary producers. However, thus far most research in this field has examined the effects of warming temperatures on nutrient production in individual species of phytoplankton. To characterize how warming affects phytoplankton-based nutrients at the community scale, we subjected naturally occurring phytoplankton assemblages to three temperature treatments (ambient, warming, heat wave) in a seven-week laboratory experiment. We used community-wide fatty acid composition and stoichiometric indicators (C:N, C:P and N:P ratios) as our measures of phytoplankton nutritional quality. By the end of the experiment, there was no effect of temperature on phytoplankton community composition. Phytoplankton communities from the heatwave treatment had decreased concentrations of C, N and P, but neither the heatwave nor warming affected community-wide C:N, C:P and N:P ratios. Both warming and the heatwave reduced phytoplankton polyunsaturated fatty acid (PUFA) content, but as the heatwave subsided, PUFA quantities in this treatment approached those found in the ambient temperature treatment. We then fed warmed phytoplankton communities to naturally-collected zooplankton assemblages and found that the PUFA composition of the zooplankton communities closely reflected that of their food source. Our results suggest that 1) temperature warming has negative effects on phytoplankton community nutritional quality, 2) these responses are not caused by broad-scale shifts in phytoplankton taxonomy, and 3) phytoplankton PUFA levels appear to closely track water temperature. Furthermore, we provide evidence that zooplankton communities experience indirect effects of temperature warming through nutritional shifts in their phytoplankton resource. Overall, this study improves our understanding of the types of phytoplankton nutrients that are affected by warming, how quickly these nutrients can respond to temperature change, and the down-stream effects of phytoplankton-based nutrients on zooplankton consumers.

On the Avalon Peninsula of Newfoundland, fairies are no longer feared and avoided (Reiti, 1991; Narvaez, 1991), but are something people have commodified and are marketing and selling. This thesis includes some of these examples: Tina White’s guided tours the Fairy Door Tours and Fairy Lore Walkabout, the Faerie Garden and Fairy Nights at the Cupids Legacy Centre, described by Claudine Garland and Peter Laracy, and the written representation by local writers Dennis Flynn and Dale Jarvis, and local publisher Marnie Parsons who owns and operates the Running the Goat: Books and Broadsides publishing company in Tors Cove. Applying the theoretical concepts of play (Masters, 2008; Eicher-Catt, 2016; Lambrow, 2020), assemblage (Santino, 1986), enchantment/re-enchantment (Magliocco, 2018; Saler, 2003, 2004), and escapism (Heilman, 1975; Young, 1976; Usherwood and Toyne, 2002), to the theoretical framework of commodification, I show how locals are adapting “our” fairy traditions and using the interest sparked by the popular culture representation of fairies to teach audiences about different aspects of Newfoundland culture, such as storytelling traditions, as well as Newfoundland values, like respect for nature and for other people. I also show how the visual representation of fairies has been more sanitized than the written form. Finally, I show how locals, both proprietors and consumers, are using these examples to create and foster a sense of local identity.

A Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Petroleum Systems Engineering, University of Regina. xviii, 139 p. During the primary stage, the in-situ generated foamy oil has been found to be responsible for an unexpected high recovery factor, a remarkably low gas-oil ratio (GOR), and a higher-than-expected well production rate. Such a phenomenon can also be artificially induced by injecting alkane solvents (e.g., methane and propane) or CO2 to a heavy oil reservoir; however, the gas exsolution of foamy oil is not yet well understood due mainly to the complicated physical processes. On the other hand, the associated emulsifications resulted from the in-situ generated surfactant(s) during alkaline flooding in a heavy oil reservoir lead to an increase in oil recovery, though no theoretical models have been made available to quantify such physical phenomena at high pressures and elevated temperatures. Physically, both gas exsolution and emulsification are closely associated with the nonequilibrium phase behaviour. Therefore, it is of fundamental and pragmatic importance to accurately quantify the nonequilibrium phase behaviour of the alkane solvent(s)-CO2/alkaline water-heavy oil systems under reservoir conditions. A novel and pragmatic technique has been developed and validated to quantify gas exsolution of alkane solvent(s)-CO2-heavy oil systems under nonequilibrium conditions. Experimentally, constant composition expansion (CCE) tests of alkane solvent(s)-CO2- heavy oil systems are conducted with a visualized PVT cell. Theoretically, a mathematical model which integrates the Peng-Robinson equation of state (PR EOS), Fick’s second law, and nonequilibrium boundary conditions has been developed. It is found that the rising of experiment temperature and pressure has negative effects on diffusion coefficient during gas exsolution processes. At a higher temperature, a larger CO2 diffusion coefficient is observed, whereas, for alkane solvents (i.e., CH4 and C3H8), a lower diffusion coefficient is attained. Also, experimental and theoretical techniques have been developed to quantify the emulsion behaviour of alkaline water-heavy oil systems at high pressures and elevated temperatures. Experimentally, oil in water (O/W) emulsions with different settling times were prepared in order to track the continuous water content distribution along time. Theoretically, two groups of population balance equations (PBEs) were applied to quantify the phase behaviour during the emulsion destabilization. By applying the emulsion inversion point (EIP) as the boundary condition, the newly developed model is able to reproduce the dynamic water content distribution in the dual-emulsion systems. Due to the corresponding changes of oil viscosity and interfacial tension (IFT), either an increase in temperature or a decrease in pressure leads to a smaller EIP and higher coalescence efficiency. As a weak alkali, Na2CO3 facilitates the stabilization of the emulsion and inhibits the influence of higher temperatures, while NaOH solution-heavy oil systems achieve emulsion inversion more easily. Student yes

Drosophila transcription factor (TF) function is phenotypically nonspecific. Phenotypic nonspecificity is defined as one phenotype being induced or rescued by multiple TFs. To explain this unexpected result, a hypothetical world of limited specificity is explored where all TFs have unique random distributions along the genome due to low information content of DNA sequence recognition and somewhat promiscuous cooperative interactions with other TFs. Transcription is an emergent property of these two conditions. From this model, explicit predictions are made. First, many more cases of TF nonspecificity are expected when examined. Second, the genetic analysis of regulatory sequences should uncover cis-element bypass and, third, genetic analysis of TF function should generally uncover differential pleiotropy. In addition, limited specificity provides evolutionary opportunity and explains the inefficiency of expression analysis in identifying genes required for biological processes.

Poster presented at SETAC Europe's 33rd Annual Meeting held in Dublin Ireland..

Newly developed Neural Network Potentials (NNPs) like ANI are powerful tools to describe these systems with a high level of accuracy but with a modest computational cost. Because they use short-range cutoffs (e.g., 5 Å), interactions outside this range are not described correctly. Significantly, London dispersion is a fundamental intermolecular force that extends beyond 5 Å, so it is neglected by current NNPs. The dispersion interaction in a chemical system can be estimated as the sum of pairwise atomic interactions with 6th, 8th, and 10th order terms (i.e., C₆, C₈, and C₁₀). The exchange hole dipole moment (XDM) model provides an accurate ab initio method for calculating these coefficients. However, a computationally intensive Density-Functional Theory (DFT) calculation is required to calculate these coefficients, so they cannot be used practically with NNPs. In this thesis, we developed a neural network to calculate these dispersion coefficients of atoms without the DFT calculation, providing an NNP that describes dispersion rigorously while maintaining the computational efficiency of NNPs. This new NNP is trained to reproduce PBE0/aug-cc-pVTZ with an XDM dispersion correction. This method was validated by comparison to high-level ab initio calculations from the DES15K test set. This method predicted intermolecular interaction energies of neutral molecules with a mean absolute error of 1.1 kcal/mol and a coefficient of determination of 0.91, demonstrating that this method has comparable accuracy to the QM method with a dramatically reduced computational cost.

Direct compounded compression molded carbon fibre long fibre thermoplastic (LFT-D) combines the high strength and stiffness of carbon fibre with a mass production manufacturing process intended to maximize fibre length. However, this process is more commonly used in industry with glass fibre. Extensive characterization of mechanical properties, spanning fundamental tensile tests to impact characterization of standard specimens and a complex automotive component, was completed to understand the strengths and deficiencies of this novel material formulation for engineering applications: fundamental uniaxial tension (quasi-static and intermediate strain rate) and three-point bending tests, tensile stress-life fatigue characterization, ISO 6603-2 instrumented impact of standard specimens, and quasi-static/low velocity impact loading of an automotive seating component. These studies provide the data necessary to advance commercial adoption of direct compounded long carbon fibre thermoplastic. Uniaxial tension and three-point bending characterization of 9% to 25% weight fraction compression molded carbon fibre LFT-D polyamide-6 was completed with orientations of 0°, ±45°, and 90°. A novel finding that has importance for process modelling was that uniaxial tension and flexural properties were higher in the +45° direction compared to –45° (tensile modulus: 20%, strength: 10%, flexural modulus: 8%). Correspondingly, engineering strain at failure for uniaxial tensile tests was 18% lower in the +45° direction. These observations are hypothesized to be the result of fibre orientation asymmetry in the compression molding charge due to the screw of the compounder. Tensile fatigue characterization was carried out for 40% (by weight) carbon fiber/polyamide 66 LFT-D composites. This characterization yielded fatigue stress-life curves (23 °C, dry as molded, R = 0.1, 3 Hz) for 0°, 45°, and 90° orientations with respect to flow. Peak stresses at which the samples achieved 1E6 cycles were 105 MPa for samples oriented in the flow direction, 72 MPa for samples oriented 45° to the flow direction, and 53 MPa for samples oriented 90° to flow. Poorly dispersed fibre with little to no wet-out were identified by SEM at the fracture surfaces for those specimens with fatigue properties near the stress-life lower bound. Further development of the direct compounding process is needed for carbon fibre. Direct/in-line compounded PA6/CF long fibre thermoplastic was also characterized under low velocity impact consistent with ISO standard 6603-2. Additionally, a quasi-static variant of the ISO method was employed to assess rate sensitivity. At quasi-static loading rates, flow region specimens were notably more brittle considering the force-deflection response. However, the energy absorption did not differ significantly between charge and flow region specimens. In terms of rate sensitivity, puncture energy under low velocity impact decreased by 18% on average with respect to quasi-static loading. Tensile specimens were extracted from an automotive seatback structure compression molded from PA66/CF. Additionally, quasi-static and low velocity impact loading of seatback components was completed. Under low velocity impact loading a local force maxima was observed for seatbacks produced with a longitudinal charge orientation. No local maxima were consistently observed for transverse charge seatbacks. In terms of rate effects: initial stiffness was 550% higher for low velocity impact with respect to quasi-static loading. Digital image correlation identified localized deformation at the hemispherical indenter for low-velocity impact indicating an inertial component to the rate sensitivity. Catastrophic failure occurred at larger deflections for low velocity impact (36% increase for longitudinal charge placement, 24% for transverse). A study of specimen size effect for quasi-static uniaxial tension puncture test was completed for compression molded direct compounded carbon fibre LFT. No significant size effects were observed for the elastic modulus or tensile strength obtained from tensile specimens with four different gauge lengths (6.25 mm to 57 mm). The failure strain decreased by 27.5% and 29.9%, respectively, across the gauge length range for the 0°/90° directions. This material was also characterized at intermediate strain rates (10 s–1 to 100 s–1) through uniaxial tension tests on a novel apparatus and ISO 6603-2 puncture tests. Intermediate strain rate tensile tests showed little to no strain rate sensitivity for the 0° and 90° directions. However, initial stiffness was approximately 50% higher for ISO 6603-2 impact tests compared to quasi-static puncture tests.

Thyroid hormones are important regulators of development and metabolism in animals. Their function via genomic and non-genomic actions is well-established in vertebrate species but remains largely elusive among invertebrates. Previous work suggests that thyroid hormones, principally 3,5,3',5'-Tetraiodo-L-thyronine (T4), regulate development to metamorphosis in sea urchins. Here we show that thyroid hormones, including T4, 3,5,3'-triiodo-l-thyronine (T3), and 3,5-Diiodothyronine (T2) accelerate initiation of skeletogenesis in sea urchin gastrulae and pluteus larvae of the sea urchin

ABSTRACT Hybridization between closely related species can generate genetic and phenotypic variation, providing valuable biological material to assess the physiological impact of the structural or functional variability of different organs. In the present study, we examined growth rates of various organs and whole body in brook char, Arctic char and their reciprocal hybrids over a period of 281 days. Parental species achieved significantly higher body mass than their hybrids. Hybridization significantly reduced the relative size of the heart, liver and spleen. The relative size of pyloric caeca did not differ among the four groups. The observed lower growth performance of the hybrids compared to parental species strongly suggests that divergence in the relative size of digestive organs, liver and heart partly dictate growth capacity. Our results also suggest that the increased variability achieved through hybridization may prove useful in a genetic selection program. Summary: This research provides a comprehensive overview of the phenotypic modifications in growth trajectories of body size and internal organs following interspecific hybridization in chars.

The cave deposits of the Lower Permian Richards Spur locality in Oklahoma, USA, have produced an incredible number of terrestrial tetrapod taxa, many of which are currently only known from this locality. One of the many recent taxa to be described from the locality was the small lanthanosuchoid parareptile