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Policy and governance simulation for marine routes
No full textThis thesis presents Policy and Governance (PoGo), a simulation framework designed to evaluate the operational impacts of maritime policy on Arctic shipping. PoGo integrates ship performance models, environmental datasets, and regulatory constraints to simulate and optimize voyages in sea ice and open-water conditions. Using Dijkstra's algorithm and cost functions based on fuel consumption, emissions, and crewing expenses, the system computes optimal routes while dynamically enforcing policy mechanisms such as POLARIS and the Carbon Intensity Indicator (CII). Developed with a multithreaded Python backend and an interactive Godot-based interface, PoGo emphasizes both computational rigor and user accessibility. Users can configure scenarios with custom vessel data, fuel types, and policy parameters, enabling detailed exploration of trade-offs in routing, emissions, and regulatory compliance. A case study to Iqaluit highlights PoGo's capacity to support decision-making through transparent, adaptable, and policy-aware simulation. This work contributes a practical tool for connecting regulatory design with operational realities in Arctic maritime navigation
Profiling NMDA receptor subcellular localization across different brain regions and disease stages in male and female 3xTg-AD mouse model
No full textAlzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by synaptic dysfunction, memory loss, and cognitive decline. N-methyl-D-aspartate receptors (NMDARs) play a critical role in neuronal health, synaptic plasticity, and learning, with distinct functions at synaptic and extrasynaptic sites that respectively promote cell survival or trigger cell death pathways. Their mislocalization could underlie neuronal dysfunction in AD.
The subcellular localization of NMDARs in AD remains poorly understood due to technical limitations. This study investigated the subcellular localization of GluN2A and GluN2B subunits using Airyscan super-resolution microscopy and 3D nearest-neighbor analysis in the CA1 region of the hippocampus and dorsal striatum of 3xTg-AD mice at two ages (2–3 and 9–12 months) and in both sexes.
Our results revealed region-, age-, and sex-dependent NMDAR mislocalization. Compared to controls, early-stage 3xTg-AD mice exhibited greater synaptic GluN2B volume and less synaptic GluN2A localization. In contrast, aged female 3xTg-AD mice showed a higher synaptic GluN2A, whereas aged male 3xTg-AD mice showed increased mislocalization of GluN2A from synaptic to extrasynaptic sites, reflecting disrupted receptor anchoring and trafficking. The dorsal striatum remained relatively stable.
These findings uncover changes in NMDAR localization during AD progression and provide insight into potential therapeutic strategies for neurodegenerative diseases
Impacts of disturbances and moose herbivory on elemental composition and species richness of cryptogams in the eastern boreal forest
No full textDisturbances are crucial components of forest renewal in boreal forests. These events generate canopy openings, thereby altering ecosystem processes such as elemental cycling, and species richness between disturbed and undisturbed forested patches. Through a continuing cycle of forest loss and regeneration, disturbances increase spatial and temporal heterogeneity across landscapes. However, forests in some areas on the island of Newfoundland, Canada are experiencing regenerative suppression caused by high densities of non-native moose. In this study, I analyzed spatial variation of total percent carbon and nitrogen, as well as species richness of lichens and mosses between canopy gaps, gap edges, and adjacent closed canopy forests. I also investigated variability between disturbance type (fire, logged, and insect) to account for site legacy effects. I observed negligible variation in arboreal macrolichen species richness and cryptogam carbon and nitrogen contents between gaps and closed canopy forests but found higher ground macrolichen species richness in gaps. Additionally, I found the highest carbon content and greatest species richness for both groups of macrolichens in fire plots, and highest nitrogen content in logged plots. My findings can help natural resource managers take information on cryptogams into account in during land use planning
"For sale: fishing boat, licences, quotas and gear": investigating the property nature of fishing licence and quotas in Newfoundland and Labrador's commercial fishery through a nomospheric lens
No full textThis thesis investigates the property nature of fishing licences and quotas in Newfoundland and Labrador's commercial fishery through the lens of legal geography and David Delaney's nomospheric framework. The research is guided by two core questions. One, are fishing licences and quotas property in this context? Two, what accounts for the ambiguity and confusion surrounding the property nature of fishing licences and quotas? Using a multiphase sequential research design, the study combines evidence gathered from document analysis, legal case review, and semi-structured interviews with fish harvesters, public servants, lawyers, and other fishing industry stakeholders, to answer these questions by way of three empirical chapters. The first chapter traces the theoretical development of the transformative nomospheric project called rights-based fisheries management (RBFM), highlighting how fisheries economists effectively and over time entangled fishing licences and quotas in the language of property. The second chapter explores how fishing licences and quotas are conceptualized in the nomospheric setting of Newfoundland and Labrador. The chapter introduces three distinct but overlapping spheres - the Legal Sphere, the Administrative Sphere, and the Everyday Sphere - to demonstrate how fishing licences and quotas are differently conceptualized, regulated, and practiced. The significance of the spheres is that they generate systemic ambiguity concerning the legal nature of fishing licences and quotas which leads in turn to nomospheric disturbances. The third chapter focuses on one of the most important of these nomospheric disturbances: Saulnier v. Royal Bank of Canada (2008). The Supreme Court of Canada decision which resolved this nomospheric disturbance found that fishing licences issued by Fisheries and Oceans Canada are sufficiently property-like for the purposes of the federal Bankruptcy and Insolvency Act and applicable provincial personal property security legislation. Despite this landmark decision, these very same fishing licences (and attached quotas) remain non-transferable privileges for the purposes of the federal Fisheries Act and associated Regulations. In addition to offering critical insights into the property nature of fishing licences and quotas in Newfoundland and Labrador, this thesis highlights the need for fish harvesters, their union, and fisheries managers to remain attentive to the contingent nature of these instruments, whose legal status may shift through legislative amendments, judicial decisions, or the introduction of new policy innovations. The thesis also contributes in significant ways to social science scholarship on fishing licences and quotas that has long engaged with, and revealed the effects of, individual transferable quotas (ITQs) on fish harvesters and fish dependent communities. It does so by revealing the complex interplay of ideology, law, policy, and practices in the commercial fishery while urging the importance for critical examination of the use of concepts such property and property rights as they apply to fishing licences and quotas in particular nomospheric settings
Relationships between stroke severity and cortical haemodynamics during hand movement in subacute and chronic stroke survivors
No full textBackground: The challenges of upper limb motor rehabilitation post-stroke validate the need for a thorough understanding of haemodynamic changes in the brain. This pilot study investigated the relationships between cortical haemodynamics and arm motor function in subacute and chronic stroke survivors. Methods: Participants in the subacute and chronic stages of stroke recovery aged 25-76 with upper limb impairment subsequent to first middle cerebral artery stroke were recruited. Haemodynamic responses during a hand-tapping task were measured with fNIRS in the sensorimotor cortex of each brain hemisphere. This study examined peak oxyhaemoglobin (HbO), time-to-peak oxyhaemoglobin, trough deoxyhaemoglobin (HbR), time-to-trough deoxyhaemoglobin concentrations and intraregional channel connectivity in relation to arm impairment scores using pearson's correlations.
Results: Ten participants were recruited, with arm impairment ranging from mild to severe. In the ipsilesional hemisphere, less arm impairment was associated with longer time-to-peak HbO in the primary motor cortex (r = 0.652, p = 0.041), deeper trough of HbR in the premotor and supplementary motor areas (r = -0.678, p = 0.031) and shallower trough HbR in the dorsolateral prefrontal cortex (r = 0.662, p = 0.037). Additionally, asynchronous activation pattern in intraregional channels was seen in five of the ten participants. Conclusion: This study suggests that cortical haemodynamic variables in the ipsilesional hemisphere may be a useful tool that indexes the severity of arm impairment after strok
Timing, geochemistry, and depositional setting of lower Paleozoic alkaline mafic volcanic rocks in the Yukon Territory and adjacent Northwest Territories: Implications for the rift and post-rift evolution of the western Laurentian margin
No full textThe breakup of the supercontinent Rodinia and development of the western Laurentian passive margin are recorded by Neoproterozoic to mid-Paleozoic igneous and sedimentary rock successions in the Canadian Cordillera. These rocks include platformal carbonate and coeval basinal clastic strata that are offset along margin-perpendicular rift-transfer faults and spatially associated with Cryogenian to Late Ordovician alkaline mafic volcanic rocks present along the ancient continental margin from Yukon Territory, Canada to Nevada, USA. This study contributes new field mapping with facies analysis, U-Pb zircon geochronology, fossil dating, and major element, trace element and Nd-Hf radiogenic isotope geochemistry of some of these alkaline mafic igneous rocks to understand the timing of emplacement, the depositional environment during eruptions, the melt sources of rocks, and their relationships to the tectonic development of the western Laurentian margin.
The Dawson fault is a prominent east-west-striking structure in central Yukon that is interpreted herein to have been active as a rift-transfer fault in the late Cambrian. This is supported by new zircon chemical abrasion-isotope dilution-thermal ionization mass spectrometry (CA-ID-TIMS) U-Pb dates from Miaolingian alkaline mafic volcanic rocks concentrated along the Dawson fault, which erupted or were emplaced immediately before the development of a regional sub-Jiangshanian (~ 494 Ma) unconformity and indicate final continental breakup occurred around ca. 501-497 Ma in the northern Canadian Cordillera. Post-rift, Upper Ordovician (453-445 Ma) alkaline mafic volcanic and plutonic rocks occur along a northwest-southeast striking segment of the Dawson fault. New bedrock mapping, geochronological, paleontological, and petrological data from lower Paleozoic rocks exposed near this fault segment indicate that localized Late Ordovician pull-apart basin development and
associated volcanism was potentially associated with dextral strike-slip reactivation of the antecedent Dawson fault.
New bedrock mapping and volcanic facies analysis of Lower Ordovician mafic rocks assigned to the Menzie Creek Formation in central Yukon suggest these deposits represent ancient seamounts that formed in a margin-parallel graben in a post-rift setting along the western Laurentian margin. The Early Ordovician age of the seamount eruptions is based on two samples from the volcanic successions that yielded high-precision CA-ID-TIMS zircon U-Pb dates of ca. 484 Ma (Tremadocian). Menzie Creek Formation volcanic rocks are interlayered with continental slope strata and contain several kilometers of hyaloclastite breccia and pillow basalt with rare sedimentary rocks. Menzie Creek Formation seamounts form a linear array parallel to the Twopete fault, an ancient extensional or strike-slip fault in central Yukon that localized mag-matism along the nascent western Laurentian margin. The whole-rock trace element and Nd-Hf isotope compositions indicate that the volcanic rocks are predominantly alkali basalt with ocean-island-like signatures consistent with the partial melting of subcontinental lithospheric mantle at ~75–100 km depth.
Alkaline igneous rocks from three different areas in southeastern Yukon and adjacent Northwest Territories occur within the Cambrian to Devonian Haywire Formation, Cambrian to Ordovician Broken Skull Formation, and Cambrian to Ordovician Crow Formation. The age of the Broken Skull Formation volcanic rocks is constrained by two high precision U-Pb zircon dates of ca. 494-493 Ma near Brintnell River in western Northwest Territories. Mafic volcanic rocks from the Haywire Formation near Island Lakes, Northwest Territories, are constrained to the Middle Ordovician by conodont microfossils from limestone and gastropod-bearing dolostone interbedded with the volcanic rocks. Crow Formation mafic volcanic rocks and gabbro are ca. 486 Ma from the Camp Creek area in southeast Yukon. Trace element geochemical results from these three areas indicate that the melts formed from the low degree partial melting of an enriched mantle source from > 75 km depth. The whole-rock Nd and Hf isotopic compositions of the mafic rocks yield initial epsilon Nd and Hf values of +2.8 to +4.1 and +4.2 to +9.2, respectively, which are consistent with melting of the subcontinental lithospheric mantle. Alkaline igneous rocks along the northern Cordilleran passive margin coincide with facies belt transitions from shallow-water rocks of the Mackenzie platform to deep-water rocks of the Selwyn basin. Major extensional fault systems that formed during rifting, which accommodated platform-to-basin transitions, were reactivated during passive margin development in the late Cambrian and Middle Ordovician and resulted in low-volume decompressional melts.
Aside from syn-rift, Miaolingian magmatism along the Dawson fault, all of the alkaline mafic igneous rocks investigated during this study erupted after lithospheric breakup during the early development of the Laurentian passive margin. The early to mid-Paleozoic counterclockwise rotation of the Laurentian craton, as indicated by published paleomagnetic studies, likely reactivated rift structures via the transfer of stress to the base of the lithosphere from mantle drag forces. It is proposed in this dissertation that normal and strike-slip fault reactivation caused periodic, post-breakup extension which resulted in small-volume, decompression partial melting of the subcontinental lithospheric mantle along western Laurentia
Influence of organizational attributes on registered nurse contributions to well-child care: a scoping review research practicum
No full textBackground: Well-child care (WCC) is a vital component of preventative care for children within primary care settings. WCC commonly consists of a series of primary care visits that encompass growth and development assessments, health screenings and education, immunizations, care coordination, and anticipatory guidance. Although Registered Nurses (RNs) are well-positioned to deliver WCC, substantial variation exists in how their roles are enacted across primary care practice environments. Ongoing challenges in primary care workforce capacity necessitate a critical analysis of professional contributions to ensure primary care provision is optimized. Current literature offers limited clarity regarding the organizational attributes that influence how, and to what extent, RNs contribute to WCC in primary care settings.
Purpose: As a Master of Nursing student, the objective of this practicum was to develop research competencies aligned with the advanced nursing practice (ANP) role. This was achieved by conducting a scoping review to describe the scope and characteristics of the literature involving organizational attributes that act as barriers or facilitators to RN contributions to WCC in high-income economies. A secondary objective was to engage in knowledge translation (KT) activities to support the dissemination of scoping review findings.
Methods: The scoping review was conducted in accordance with the Joanna Briggs Institute (JBI) scoping review methodology. Data were extracted in alignment with the Nursing Care Organization Framework (NCOF), and the ‘best fit’ framework was utilized to guide data analysis and synthesis. Data reporting adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses Extension for Scoping Review (PRISMA-ScR) approach. A manuscript was prepared for submission to the special edition of BMC Primary Care focusing on the primary care workforce. To facilitate KT, two abstracts were developed and accepted for electronic poster presentations at the Trillium Primary Health Care Research Day 2025 and the Memorial University of Newfoundland Faculty of Nursing 2025 Research Exchange. Findings: Thirteen articles representing a range of high-income countries were included in the scoping review. Findings suggest a close alignment between organizational attributes derived from the NCOF and RN contributions to WCC. Specific findings include clear gaps in the education and training of primary care nurses, structural constraints that inhibit nurse contributions to WCC, and potential opportunities to expand nursing roles beyond core WCC functions.
Conclusions: Future research should focus on identifying how organizational attributes can be leveraged or mitigated to optimize nursing contributions to WCC. Targeted exploration of these aspects will inform strategies that strengthen nursing roles in WCC provision, enhancing the quality of preventative care as evidenced by patient and system-level outcomes, and amplifying primary care workforce capacity
Battery energy storage systems for energy arbitrage: market selection and price forecasting optimization
No full textThe rapid integration of variable renewable energy (VRE) sources into electricity grids has disrupted traditional power market dynamics and created new opportunities for grid-scale battery energy storage system (BESS) ventures. This thesis presents an integrated, data-driven framework for optimizing the investment and operational decision-making processes of battery energy storage system-enabled energy arbitrage (BESS-EA) systems. The first component develops a novel energy arbitrage feasibility (EAF) scoring methodology to evaluate the locational suitability of 29 European electricity markets. Using eight years of hourly wholesale electricity price data (2015–2023) along with regulatory, volatility, and macroeconomic indicators—including electricity supply-origin risk (ESOR), GDP per capita (purchasing power parity), and index of economic freedom (IEF)—the EAF score facilitates standardized, cross-country investment assessment across five investor preference scenarios. Results identify Estonia and Luxembourg as optimal BESS-EA markets across five scenarios.
The second component addresses the critical challenge of electricity price forecasting for bid optimization by introducing a hybrid long short-term memory (LSTM) and exponentially weighted moving average (EWMA) architecture. Trained on Austria's market data, the model achieves a root mean square error (RMSE) of €1.2207/MWhe and incorporates 95% bootstrap confidence intervals for risk quantification. By simultaneously capturing long-term temporal trends and short-term volatility patterns, the model supports robust intraday BESS bid decisions in wholesale and ancillary service markets
Geometric disturbance observer based nonlinear model predictive control and trajectory planning in safe convex corridors for UAVs
No full textThis thesis develops and validates an integrated framework for UAV autonomy in
complex environments, spanning disturbance-resilient control, trajectory planning in
obstacle-dense environments, and a hardware-in-the-loop (HITL) simulation platform
for validating planning and control algorithms.
The thesis consists of three main components. First, a geometric disturbance
observer-based nonlinear model predictive control (NMPC) architecture is presented
for quadrotor trajectory tracking. The framework couples an extended-state extended
Kalman filter formulated on the SO(3) manifold with a disturbance-aware NMPC that
embeds six-degree-of-freedom disturbance estimates as time-varying inputs within the
prediction model, enabling proactive compensation within the receding-horizon optimization.
Second, a time-efficient trajectory planning framework for fixed-wing UAVs
combines greedy corridor generation along bidirectional rapidly-exploring random tree
path with differential-flatness-based convex optimization. The approach constructs a
safe corridor of overlapping convex regions significantly faster than workspace-wide
convex decomposition methods and formulates the complete planning problem as a
single convex quadratic program, guaranteeing collision-free and dynamically feasible
solutions without nonlinear refinement. Third, a comprehensive hardware-in-the-loop
ii
testing framework is developed for the DJI M300 RTK platform, integrating the DJI
Manifold 2-G onboard computer with the flight controller through the DJI Onboard
SDK and Robot Operating System.
Simulation results demonstrate that the geometric disturbance observer-based
NMPC achieves 60% reduction in position root mean square error compared to
baseline NMPC under periodic six-degree-of-freedom disturbances. The proposed
trajectory planning framework achieves a 36% reduction in traversal time with a
17� computational speedup relative to the Graph of Convex Sets (GCS) planner
refined with Kinodynamic Trajectory Optimization (KTO) as the baseline method,
and demonstrating a 99.4% success rate across 1,001 randomized scenarios. The
hardware-in-the-loop simulation framework for the DJI M300 RTK drone successfully
validates the implementations of proportional�integral�derivative (PID), linear
quadratic regulator (LQR), and model predictive control (MPC) algorithms. Together,
these contributions form a complete pipeline for robust UAV control and
planning: from disturbance-resilient NMPC and convex optimization-based trajectory
planning to pre-flight validation on real hardware, providing a foundation for
safer autonomous UAV operations in uncertain and obstacle-dense environments
Identifying diatom indicator species across environmental gradients in Newfoundland peatlands
No full textPeatlands, both bogs and fens, are organic wetlands that provide a myriad of ecosystem services. To support proper stewardship of peatlands, a more thorough understanding of spatial variability across them is required. To address this, we investigated the abiotic drivers of surface diatom assemblage composition across Newfoundland peatlands. We collected samples from 26 peatlands representing all 9 Newfoundland ecoregions. At each peatland, a surface peat sample was harvested from each representative microhabitat (e.g., hummocks, hollows, pools), for a total of 78 samples, to account for variability in abiotic conditions. We found 10 significant indicator species (p < 0.1), representing four clusters of environmental conditions. Our findings suggest that common indicator species are ubiquitous across certain clusters of environmental conditions within Newfoundland peatlands, and that these species are reflective of those conditions. Indicator species identified via this research can be used as a biomonitoring tool to track abiotic conditions in peatlands across spatial and temporal scales. Results will be used as a calibration set for paleoecological reconstruction and will facilitate identification and conservation of Newfoundland’s peatlands as effective carbon sinks and reservoirs of biodiversity