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- ItemDonor-stabilised fluorido cations of groups 15 and 16(Lethbridge, Alta. : University of Lethbridge, Dept. of Chemistry and Biochemistry, 2025) O'Donnell, Felix; University of Lethbridge. Faculty of Arts and Science; Gerken, MichaelThe fluoride-ion donor properties of the strong Lewis-acids SbF5 and AsF5 were investigated. In the presence of the bidentate nitrogen base 1,10-phenanthroline (phen) SbF5 and AsF5 were found to autoionise generating [PnF4(phen)][PnF6] (Pn = As or Sb) salts; this is the first time that SbF5 has demonstrated the ability to act as a fluoride-ion donor. In the presence of the more flexible nitrogen base 2,2′-bipyridine (bipy), SbF5 was again found to autoionise yielding [SbF4(bipy)][SbF6], whereas AsF5 forms the neutral adduct (AsF5)2·bipy. In the presence of the tridentate base 2,2′:6′,2′′-terpyridine (terpy) SbF5 autoionises to form [SbF4(terpy)][SbF6]; the [SbF4(terpy)]+ cation is the first structurally characterised fluorido Sb(V) complex with a coordination number of seven and adopts a heavily distorted pentagonal bipyramidal geometry. The structure and bonding in these unique systems was studied using a combination of spectroscopic, crystallographic and computational techniques. The [SF3]+ cation forms 1:1 adducts with pyridine and 4-dimethylaminopyridine (DMAP) which adopt different structures. Whereas pyridine coordinates in the axial position of the seesaw-geometry, DMAP is located in the equatorial position. The latter structure leads to facile dismutation to the [SF2(dmap)2]2+ cation and SF4, while [SF3(py)]+ is stable towards dismutation. Further dismutation afforded the square-pyramidal [SF(dmap)4]3+ cation. Attempts to form adducts of [SF3]+ cation with triphenylphosphine oxide, resulted in deoxofluorination.
- ItemDemocratic legitimacy through the lens of national identity: the Basque Country and Spain(Lethbridge, Alta. : University of Lethbridge, Dept. of Political Science, 2025) Ayotte, Francis; University of Lethbridge. Faculty of Arts and Science; Kerr, StephanieIn the decades emerging after the creation of the liberal multicultural thesis in the 1990s, it has become increasingly apparent that various obstacles have greatly obstructed the development of pluralist and multicultural policies with Western liberal democratic states. Such policies have largely stagnated or regressed, and there has been a noticeable reemergence of majority nationalism and what has been termed ‘majority backlash.’ On the other side, these issues have only increased the sense of illegitimacy of these states from the perspective of minority communities, especially national minorities in multinational states. This thesis utilizes poststructural and agonistic democracy theories to consider and theorize how liberalism’s insistence on impartiality and rationality makes it struggle to account for tensions which emerge symbolically around identity, primarily in this case, national identity. This thesis highlights how these tensions around identity manifest in the real world by conducting a discourse analysis on two distinct national groups within one nation-state – Spain and the minority Basque nation. Examining diverging narratives regarding the constitution of the demos and the characteristics assigned to it during this period underscores the problematic assertion of universality in liberal democratic theory by first outlining the significance of the symbolic dimension of democratic representation and legitimacy. It is thus argued that the role of majority nationalism in liberal democracies cannot be sidestepped or ignored in multicultural and pluralist theories of democracy due to its foundational role in legitimating liberal democratic order.
- ItemBehavior analysis of catching using 3D pose estimation(Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, 2025) Mazrouei, AmirHossein; University of Lethbridge. Faculty of Arts and Science; Whishaw, Ian; Mohagerani, M. H.Catching, a complex and fundamental prehension task, is crucial for daily life yet remains understudied despite its implications for robotics, rehabilitation, and neuroprosthetics. This thesis investigates the intricate sensorimotor coordination involved in human catching, building upon theories like the Dual Visuomotor Channel (DVC) and Multiple Motor Channel (MMC) to understand how the brain orchestrates dynamic hand movements. Ten right-handed participants engaged in externally thrown, self-thrown, and visually guided "pretend" catches using four ball sizes. Behavior was recorded with three GoPro cameras, and 3D pose estimation was performed via FreeMocap (Matthis & Cherian, 2022), leveraging MediaPipe (Zhang et al., 2020) for 2D analysis and triangulation for 3D reconstruction. Three primary kinematic metrics were quantified: 1) Euclidean distance between the thumb tip and other fingertips (opposable distance); 2) Perpendicular distance from each fingertip to the palm plane (prehensile distance); and 3) The hand's rotation angle in the X-Z plane, derived from the palm's normal vector. Results revealed Maximum Pregrasp Aperture (MPA) scaled linearly with ball diameter, indicating anticipatory hand shaping. Distinct grasping strategies emerged for different ball sizes: larger balls elicited "precision catches" characterized by significant finger splay and thumb-pinky opposition, while smaller balls often resulted in "power catches" with minimal thumb involvement and greater finger flexion into the palm. Self-catches further highlighted the interplay of anticipatory and feedback control. These findings enhance understanding of human prehension, providing quantitative data valuable for advancing motor control models, developing adaptive robotic systems, and improving human-machine interfaces.
- ItemBecoming neoliberal: myths, memory and subjectivity in Los 80(Lethbridge, Alta. : University of Lethbridge, Dept. of Sociology, 2025) Fruhbrodt, Ingrid O.; University of Lethbridge. Faculty of Arts and Science; Mair, KimberlyThis thesis examines the Chilean television series Los 80 as a cultural text that negotiates the tensions of neoliberal subjectivity in Chile. Through critical discourse analysis, and a variety of qualitative approaches appropriate to the study of multimodal texts, this thesis identifies and analyzes three cultural myths articulated in the series and investigates their part in reinforcing or disrupting neoliberal values. By evaluating the interplay of material culture, dialogue and imagery, I argue that Los 80 functions as both a reflection and a critique of the enduring neoliberal framework installed during the dictatorship. I explore the ways in which nostalgia and material culture intersect to naturalize or challenge these ideologies. This work contributes to the broader ongoing discussions between memory, images and identity, which shape the collective understanding of Chile’s present, past and future through popular culture.
- ItemQuantifying vegetation structure and fire fuels in montane pine forests impacted by mountain pine beetle using remotely piloted aircraft system multi-spectral, photogrammetric and lidar technologies(Lethbridge, Alta. : University of Lethbridge, Dept. of Geography and Environment, 2025) Parsian, Saeid; University of Lethbridge. Faculty of Arts and Science; Chasmer, Laura; Hopkinson, ChristopherJasper National Park, one of the oldest Canadian national parks, has a long history of fire suppression. This has increased the homogeneity of mature pine forests within the park over time, and in recent years has been severely affected by mountain pine beetle (Dendroctonus ponderosae) outbreak. Tree mortality associated with Mountain Pine Beetle (MPB), dry fuels, and the potential for fire in the Athabasca and Miette Valleys is of significant concern to the park. Measuring forest fire fuels in the field is difficult and time-consuming, and field plots do not measure all the spatial variability of fuel distribution (though field measurements are effective for measuring surface organic layers (e.g., duff layers), which are difficult to measure using remote sensing or other techniques). Remote sensing platforms, such as remotely piloted aircraft systems (RPAS), can be used to quantify 3D structures and fuels, however, RPAS platforms and sensors have not been fully explored as a tool for identifying fuels in MPB-affected stands. Therefore, the objectives of this thesis are to: 1) quantify and compare fuel attributes using RPAS-photogrammetric, lidar point clouds and 2D multispectral imagery; and 2) examine the distribution of fire fuels based on the proportion of proportion of tree mortality, likely associated with MPB outbreak phases. To answer these objectives, geographic object-based image analysis (GEOBIA) was employed to identify vegetation species, MPB phases and map coarse woody debris. Then, 3D fuel attributes were quantified using RPAS-photogrammetric and -lidar point clouds (a single wavelength collected using the Zenmuse L1 sensor (as a comparison). The results indicated that GEOBIA effectively identified tree species and achieved an overall accuracy of approximately 90% compared to field-based validation. Photogrammetric point clouds were accurate for quantifying tree structures, including tree height (R2= 0.96, Root Mean Square Error (RMSE)= 1.22 m, Normal Root Mean Square Error (NRMSE)= 6% and Bias=-0.34 m). Crown base height estimated using a novel region-based approach was also identified when compared with field-based validation (R2= 0.76, RMSE= 2.29 m, NRMSE=17%, Bias= 0.73 m). RPAS-lidar point clouds demonstrate higher accuracy in measuring tree height (R2= 0.99, RMSE= 0.59 m, NRMSE=3% and Bias= -0.23) and crown base height (R2= 0.91, RMSE= 1.32 m, NRMSE= 8% and Bias= 0.16 m) compared with measured, illustrating the value of using lidar, especially in dense canopies. RPAS point clouds demonstrated moderate accuracy for estimating crown fuel load (R2 = 0.38, RMSE = 1.92 kg. tree-1, NRMSE=16% and Bias= 0.30 kg. tree-1) Lastly, fuel distribution was assessed by comparing foliage volume and canopy fuel load and bulk density across 16 plots, and a downward shift was observed in canopy fuels over the progression of MPB outbreaks from green to gray phases. Unaffected plots (e.g., plot 15 (V = 2600 m3) had greater foliage volume and canopy fuel load than affected plots (e.g., plot 11 (V = 515 m3)).