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Coastal cities are grappling with how to shift their approach in designing the built environment to respond to global warming and sea level rise. With the potential increase of sea level rise by 1 metre by the year 2100, and climate change projecting more intense and frequent storms to British Columbia’s coasts, Vancouver will need to consider more resilient approaches to address flood risk along its shores. One area that will be exposed to flood risks includes the False Creek Flats, a historic tidal flat converted to rail and industrial hub in the core of the city, and on the cusp of transforming into the city’s next employment hub. At present, it is indiscernible that the False Creek Flats at one time was a historic tidal flat with a rich ecology supporting a variety of plants and wildlife, providing food and sustenance to the Indigenous people whose traditional territory included this land. The emergence of the rail and industry erased this history, the connection to the water, and the dynamic coastal processes that shaped the landscape. With the False Creek Flats undergoing a significant transformation over the next number of years, there is a window of opportunity to reconnect False Creek Flats to the coastal landscape, while also making room for flood waters and shifting perspectives on how we live with and build with water. This practicum seeks to develop a resilient design approach for False Creek Flats through three lenses: robustness, ensuring people are safe; adaptive, making room for the water; and transformative, shifting perspectives through design interventions. Leveraging the opportunity to make False Creek Flats resilient to climate change and flooding will benefit Vancouver by creating opportunities to shift public perspectives on how the city should adapt to sea level rise and climate change, while also bolstering public policy that will make the city and its residents more adaptive and resilient to change.

The Lake Sturgeon (Acipenser fulvescens) continues to grow throughout life, though the process by which muscle stem cells, called satellite cells (SCs) contribute to formation of fibers in the myotome is largely unknown in this endangered fish. Since muscle function and growth are critical to survival, it is important to understand the functional basis of fiber growth, and how SCs provide daughter cells that fuse into fibers in myotome development and regeneration. The hypotheses are that during aging: the cell cycle of SCs lengthens, the ratio of SCs to myonuclei decreases, and myonuclear domain increases. This experiment used the single fiber model and a pulse-chase design in which exposure to bromodeoxyuridine (BrdU) labeled S-phase for the first 2 hr in culture. Myofibers were isolated from 20-40 fish per age (1-6 months post-hatch). After fiber culture for 24 hours, fibers were fixed and stained for BrdU or Pax7 (expressed by myogenic stem cells) with colour detection. The number of Pax7- or BrdU-positive nuclei and the total number nuclei associated were counted per fiber in 8-20 fibers per dish. Results showed a significant change in the ratio of Pax7+ SCs to myonuclei as the fish age (p < 0.05) with an apparent decrease in cell cycle duration with increasing age (p < 0.05). This investigation adds to our understanding of SC contributions to myofiber growth in the developing Lake Sturgeon and results will be a new foundation for future research on the role of environmental influences on muscle in Lake Sturgeon.

Polyvinyl acetate and other polyvinyl esters, and their copolymers are used in coatings, adhesives and plastics, and hence fundamental understanding of the mechanisms and polymerization kinetics is vital for process development, and production of existing and new polymer grades in an effective and safe manner. The propagation kinetics of radical homopolymerization (bulk) of vinyl acetate (VAc), vinyl pivalate (VPi) and vinyl benzoate (VBz) was studied using Pulsed-Laser Polymerization coupled with Size Exclusion Chromatography (PLP-SEC) at laser pulse repetition rate (prr) between 2 and 500 Hz, and the temperature range of 25 - 90 °C. The propagation rate coefficient, kp, determined for VAc and VPi increases significantly with prr (20 % between 200 and 500 Hz prr), with the kp value for VPi ~50 % higher than that of VAc. This significant increase in kp with prr has been explained by the head-to-head addition defects that occur during vinyl ester polymerizations. For VBz, no kp value was reported due to lack of PLP-structure, likely due to resonance stabilization of the radical. Solution polymerization of VAc and VPi was also studied by PLP-SEC using ethyl acetate (EAc) and heptane (50 % by volume) at 50 °C, with the kp values having no substantial solvent effect. The polymerization kinetics of these vinyl ester monomers were also investigated using small-scale batch polymerization at 60 °C both in bulk and in solution (using EAc). The monomer conversion profiles obtained showed the same pattern in both bulk and solution, with the rate of conversion faster for VAc than VBz, and VPi even faster, trends consistent with the kp values determined using PLP-SEC. Kinetic models were implemented in the Predici software package, and are shown to fit the experimental batch polymerization data reasonably well.

Background: There is impaired neurotrophic growth factor signaling, AMP-activated protein kinase (AMPK) activity and mitochondrial function in dorsal root ganglia (DRG) of animal models of type 1 and type 2 diabetes exhibiting diabetic sensorimotor polyneuropathy (DSPN). We hypothesized that loss of direct insulin or insulin-like growth factor 1 (IGF-1) signaling in diabetes drives depression of AMPK activity and mitochondrial function, both contributing to development of DSPN. Methods: Age-matched control Sprague-Dawley rats and streptozotocin (STZ)-induced type 1 diabetic rats with/without IGF-1 therapy or insulin implants were used for in vivo studies. For in vitro studies, adult DRG neurons derived from control or STZ-diabetic rats were cultured under defined conditions and treated with/without IGF-1 or insulin. Activators or inhibitors targeting components of the insulin/IGF-1 signaling pathways were used to unravel the mechanism of insulin/IGF-1 action in DRG neurons. Results: Insulin increased Akt phosphorylation and neurite outgrowth, and augmented mitochondrial function in DRG cultures derived from control or type 1 diabetic rats. In STZ-diabetic rats insulin implants reversed thermal sensitivity, increased dermal nerve density and restored the expression/activity of respiratory chain proteins in DRG. Decreased expression of mRNAs for IGF-1, AMPKα2 and ATP5a1 (subunit of ATPase) occurred in DRG of diabetic vs. control rats. IGF-1 up-regulated mRNA levels of these genes in cultured DRG neurons from control or diabetic rats. IGF-1 elevation of mitochondrial function, mtDNA and neurite outgrowth was suppressed by inhibition of AMPK (via siRNA). IGF-1 therapy in diabetic rats reversed thermal hypoalgesia, raised corneal nerve density and prevented tricarboxylic acid (TCA) pathway metabolite build-up in the sciatic nerve. Endogenous IGF-1 gene expression in neurons of the DRG was suppressed by hyperglycemia and rescued by treatment with IGF-1 or the aldose reductase inhibitor, sorbinil. Transcription factors NFAT1 and CEBP-β bound to the IGF-1 promoter in DRG tissue at higher levels in control vs diabetic rats. Inhibition of endogenous IGF-1 down-regulated Akt S473 phosphorylation and background neurite outgrowth in cultured DRG neurons. Conclusions: Insulin/IGF-1 therapy elevates mitochondrial function via AMPK to drive axonal repair in DSPN. Downregulation of endogenous IGF-1 in DRG neurons in diabetes may contribute to the pathogenesis of DSPN.

The educational needs of adolescent girls have never really been met by schools leading to a variety of social, emotional and aspirational problems for girls and women alike. In this speculative inquiry I have explored the work of care ethicists, imaginative educators, critical theorists and groups outside of schools to develop a new framework for educating girls based upon the needs that I have identified as critical and unmet for far too many girls. I have surmised that girls’ needs for belonging, identity, competency and caring spirit could be better met and could lead to voice, agency and freedom for girls if schools were to implement the ideas contained in my critical framework.

Time course changes in oxylipin profiles among healthy, young individuals consuming high doses of alpha-linolenic acid (ALA) and docosahexaenoic acid (DHA) remain to be determined. Differences in lipid metabolism suggest the importance of separating sexes when investigating the effect of omega-3 supplementation on the oxylipin profile. Individuals (n=12) participated in a double-blind randomized cross-over trial where ALA oil (4g/day ALA) and DHA oil (4g/day DHA) were consumed for four weeks. Oxylipins from plasma, serum, and supplemental oils were analyzed. Females responded more immediately than males to DHA oil treatment and had higher levels of several DHA derived oxylipins, while ALA oil had a minimal effect on oxylipin production. Several oxylipins were elevated in serum when compared to plasma. Further, oxylipins were present in both supplemental oils. These results can be used to further explore oxylipin profiles in males and females and to help explain the impact of omega-3 supplementation.

The Pseudoflow algorithm is used to outline the ultimate pit limit by finding the maximum net value of the blocks extracted, while respecting precedences for their extraction. It works by modelling the blocks as a direct graph network and solving the minimum cut problem. Outlining the ultimate pit limit allows mine practitioners to design and plan an open pit operation. This guide provides a framework for running Pseudoflow in python along with a brief description of the method and a copper deposit application to exemplify its use.

This thesis investigates novel ways of using wide area synchrophasor measurements for implementing response-based emergency control operations. Two synchrophasor measurement based Remedial Action Schemes (RASs), one to prevent cascaded tripping of transmission lines due to overloading when a major tie-line exporting power is tripped and the other to prevent uncontrolled islanding and blackouts due to transient instability, were developed. The RAS proposed for overload prevention in Manitoba Hydro grid acts to quickly reduce the power delivered from HVdc converters during the tripping of tie-lines exporting power to USA. The second RAS performs controlled islanding to prevent transient instability.