26734 research outputs found
Sort by
Association between the Clinical and Economic Outcomes and Specialist Payment Model in the Care of Patients with Heart Failure in Alberta, Canada
No full textObjective: Heart failure (HF) affects approximately 2% of adults in Alberta. Most HF care is delivered by either primary care practitioners, internal medicine physicians, or cardiologists. Payment model design for these physicians may impact decision-making with respect to resource utilization and, hence overall healthcare costs in the care of HF patients. Our study focuses on physician payment models for internists and cardiologists in the context of an HF population. Prior analyses have shown that fee-for-service (FFS) cardiologists and internists perform two to three times more tests than salaried cardiologists and internists. It is not clear that this increased utilization has a favourable impact on clinical outcomes. This thesis is presented in two parts. First, a systematic review comprehensively summarizes the existing literature on cardiology payment models and the association with clinical outcomes. Second, an Alberta-based retrospective comparison of five-year healthcare utilization, clinical and cost outcomes between HF patients seen by FFS and salaried cardiologists and internists is presented. Methods: The systematic review searched the literature from database inception to August 2025 for articles relevant to cardiologists' payment models and reported clinical and cost outcomes. 4,156 publications were found, of which 87 were included for full-text review. A total of 6 publications met the inclusion criteria for final analysis. The title and abstracts were screened independently by three reviewers, followed by the full text by two reviewers, and the systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A narrative approach was followed to report the overall outcomes due to missing data, differences in patient population, healthcare setting, measures of endpoints, cardiac testing, and procedures. In the retrospective population-based cohort study, newly referred adult HF patients seen by cardiologists or internists between 2014 and 2018 were identified using new consult codes from physician claims and International Classification of Diseases, 9th and 10th revision codes from administrative data, then followed for five years from the index visit. Propensity score matching balanced baseline characteristics between the FFS versus the Salaried group. Healthcare utilization including cardiac tests, subsequent follow-up visits, and clinical outcomes such as hospitalizations due to HF, emergency department visits due to HF, and all-cause mortality were compared. Direct healthcare costs were estimated using a gross-costing approach and adjusted for 2024-year inflation. Subgroup and sensitivity analyses were performed. Conclusion: For the care of HF patients in Alberta, patients with HF seen by FFS specialists consistently received higher rates of cardiac testing, resulting in significantly higher testing costs and higher overall per-patient costs over five years, without corresponding improvements in patient outcomes. No statistical difference in all-cause mortality was observed between patients cared for by FFS and salaried specialists. Thus, a salary-based payment model for cardiologists and internists may improve health system value through a structuring payment incentive to control health system costs without any apparent adverse effect on key HF patient outcomes
Overground robotic walker use in the home and community: a six-month prospective cohort study
No full textAbstract Background Outcomes following long-term use of overground robotic walkers have not been studied, even though children with mobility impairments are using these devices for extended periods. We aimed to evaluate the impacts of six months of overground robotic walker use in the home and community. Methods An observational cohort study was conducted with a volunteer sample of 171 participants with mobility impairments who privately obtained an overground robotic walker. Participant-initiated overground robotic walker use in the home and community was evaluated over six-months. The primary outcome of functional ability was assessed by parent report using the Gillette Functional Assessment Questionnaire (FAQ). Secondary outcome measures were parent-reported physical activity, positive affect, sleep disturbance, and bowel movement frequency. Questionnaires were sent digitally at baseline (when users received device use training), and then 1-Month, 3-Months and 6-Months later. The device tracked monthly usage, specifically number of steps, minutes of use, average cadence (steps/minute), and the number of times the device was used. Results Median participant age was 6 years (range 1 to 24), 42.1% were female, 70.8% had a diagnosis of cerebral palsy, and most were not independently ambulatory (97.3% of participants who reported function). Adjusted cumulative link mixed models demonstrated a significant main effect of time for FAQ scores, with increased log odds of a higher FAQ score at each time point (ß=0.86, 95% CI [0.25, 1.46], p = 0.006). The median FAQ score increased from 1 at baseline to 2 at subsequent time points. Adjusted repeated measures linear mixed-effects models demonstrated significant main effects of time for secondary outcomes, with improvements in physical activity scores (ß=0.96, 95% CI [0.21, 1.71], p = 0.012), sleep disturbance scores (ß=-0.82, 95% CI [-1.61, -0.04], p = 0.040), average cadence (steps/minute) (ß=1.86, 95% CI [0.61, 3.11], p = 0.004), and also decreases in the number of times the device was used per month (ß=-0.95, 95% CI [-1.63, -0.26], p = 0.007). Device usage time and total steps per month did not significantly change over time. Conclusions Six months of overground robotic walker use resulted in modest, statistically significant improvements in functional ability and secondary outcomes linked to physical inactivity. Device usage time was consistent over time, suggesting feasibility of long-term home and community use
Interfacial Dynamics of Drops from Emulsions to In-situ Formed Soft Particles
No full textMultiphase systems are ubiquitous in natural and engineered processes, where interactions between distinct fluid phases govern stability, transport, and dynamic behavior. In such systems, interfaces play a key role, governing capillary forces, interfacial stresses, and mass transfer processes that ultimately determine system performance. While the mechanics of simple fluid interfaces are well understood, many practical applications involve complex fluids whose interfacial and bulk properties evolve in time due to chemical reactions or physical transformations. Understanding how these evolving properties influence interfacial dynamics remains a significant challenge. This thesis investigates how in situ colloidal particle formation and time-dependent internal phase evolution affect the behavior of oil-water interfaces under both static and dynamic conditions. The work focuses on reactive emulsion systems in which microemulsion formation and sol–gel chemistry enable the generation of surface-active colloidal structures directly at oil–water interfaces or within dispersed droplets. These systems provide a controlled platform to examine the coupling between interfacial material formation, evolving rheology, and macroscopic flow behavior. At static oil–water interfaces, in situ particle generation leads to the formation of interfacial assemblies that modify interfacial properties and introduce mechanical resistance to deformation. Under dynamic conditions, internal phase evolution and particle formation significantly alter filament thinning and pinch-off dynamics, resulting in slower thinning rates and increased filament stability compared to systems with liquid internal phases. During droplet impact, spreading, and evaporation on solid surfaces, internal phase transformations suppress spreading, reduce evaporation rates, and produce distinct final deposition morphologies characterized by heterogeneous and mechanically constrained deposits. This thesis establishes direct links between interfacial material formation, internal phase transitions, and dynamic interfacial behavior. The findings provide physical insight into how reactive emulsions can be used to engineer adaptive interfaces and offer strategies for controlling interfacial mechanics and deposition outcomes in applications such as coating, printing, enhanced oil recovery, and controlled material delivery
Towards High Quality, Dynamic and Faster 3D Gaussian Splatting for Streaming
No full text3D Gaussian Splatting (3DGS) has recently emerged as a powerful technique for novel-view synthesis, offering substantial advantages over Neural Radiance Fields (NeRF) in training efficiency, rendering speed, and memory consumption. However, real-time streaming of 3DGS over commercial networks remains challenging due to long training times, large data volumes, high bit-rate requirements, and computationally intensive rendering. This thesis proposes a framework and methods to address these challenges. First, to reduce training time while improving reconstruction quality, we introduce a coarse-to-fine progressive training strategy for high-resolution 3DGS. This approach improves reconstruction accuracy by an average of 5.70\% in PSNR, 4.86\% in SSIM, and 13.6\% in LPIPS, while achieving an average training speed-up of 3.23x ( 223\% acceleration). Second, to enable efficient transmission over commercial networks, we present a lightweight compression framework for dynamic 3DGS sequences. The framework organizes frames into a Group-of-Pictures (GOP) structure with reference and predictive frames, significantly reducing data size while preserving visual fidelity and rendering efficiency. The proposed method achieves approximately a 97\% reduction in data size compared to standard 3DGS, making real-time streaming feasible. Finally, to accelerate 3DGS rendering, we develop a layered algorithm guided by saliency maps and Fisher information, allowing independent layers of scene rendering on GPU. This method reduces rendering time by up to 71\% while maintaining high visual quality. In summary, this thesis addresses the key limitations of 3D Gaussian Splatting that hinder its streaming. By accelerating training, significantly reducing data size, and enabling faster rendering through layered processing, the proposed methods collectively make 3DGS more practical for real-world applications
Unsettling the City: Canadian Animators and Their Interpretations of the Urbanscape
No full textThe purpose of this research was to uncover independent Canadian animators’ interpretations of urbanscapes, as displayed in their films and in their own words. Through a series of interviews that were conducted with 10 independent filmmakers, this thesis provides insight into contemporary Canadian animators' artistic identity, material animation processes, and representations of urban environments. The body of this thesis is organized into three chapters: the Art, the Artist, and the City. In Chapter 1, “The Art,” the artists’ experiences and understandings of materials, skills, and processes are explored. Broader perceptions of the animation medium are also discussed, for example, the role of play in the creative process, how animation is distinguished from other forms of film, and animation’s relationship to dreaming. In the second chapter, “The Artist,” the animator’s role is explored. In their own words, the artists situate themselves and their artworks in broader society, sharing how they perceive their purpose in communities, their motivations and inspirations, and the relationship that is formed between themselves as artists and their audiences. This chapter also locates the animator inside a long tradition of avant-garde artists and documents the artists’ reactions to Roland Barthes’ theory of “death of the author.” Finally, in Chapter 3, “The City,” the artists share their opinions on urban life, the ways they conceptualize urban environments, how they are shaped by the cities they live in and, most importantly, how they in turn shape and interpret those cities in their creative works. This thesis argues that contemporary independent animators both intentionally and unintentionally interpret the city through their creative practices, inadvertently creating spaces where the status quo in our modern urban lives can be questioned and reframed
Performance of Floating Biofiltration in Methane Oxidation
No full textWaste lagoons in the livestock industry are significant sources of methane (CH₄), a potent greenhouse gas that contributes substantially to climate change. Biofiltration, which relies on microbial oxidation, has emerged as a sustainable and effective method for mitigating methane emissions. This study introduces a novel floating biofiltration system designed to enhance methane removal directly from the surface of waste lagoons using integrated compost- and plant-based floating biofilters. Four biofilter configurations were evaluated over a four-month period: compost-only, plant-only (using cattail Typha spp.), and two mixed compost–plant systems. The performance of these setups was assessed by monitoring oxidation efficiency, microbial population dynamics, nutrient availability, moisture content, and the maximum methane oxidation rate (Vₘₐₓ). The mixed compost–plant configurations achieved the highest methane removal efficiency, reaching up to around 70% and the highest Vₘₐₓ of 3.1–3.9 μmol CH₄ g⁻¹ h⁻¹ under the middle condition. These setups also showed a notable increase in methanotroph populations, with Type I in compost reaching 32.8% after four months and Type II near roots peaking at 19.4% after two months. In comparison, the compost-only system reached a removal efficiency of around 60% with a Vₘₐₓ of 2.3 μmol CH₄ g⁻¹ h⁻¹ and Type I abundance increasing steadily from 3.5% to 32.8%, while the plant-only setup achieved a removal efficiency of around 50% and a Vₘₐₓ of 1.9 μmol CH₄ g⁻¹ h⁻¹, with Type II abundance declining from 19.4% at two months to 8–11% during dormancy. The vegetation helped maintain favorable moisture conditions and released root exudates that stimulated microbial activity. However, this beneficial effect declined during plant dormancy, highlighting a key limitation for year-round applications. Moreover, the linear relationship between surface methane concentration and methane flux in these systems was confirmed, consistent with previous studies conducted in other methane-oxidizing systems. These findings demonstrate that incorporating cattail into floating biofilters can significantly improve methane mitigation from waste lagoons. While the mixed biofilter design shows strong potential for scalable, nature-based methane reduction strategies, its seasonal variability warrants further optimization for consistent year-round performance in livestock waste management systems
Investigating Systemic Microbiota-Specific T Cells Using the Lymphocytic Choriomeningitis Virus Infection Model
No full textIt has been well-established that the intestinal microbiota has significant influence over the development and regulation of not only mucosal, but systemic immunity. Of particular importance is microbiota influence on the adaptive immune system, epitomized by the manipulation of the T cell compartment and its cell subset composition. Through complex and context-dependent mechanisms, the intestinal microbiota has been shown to influence effector cell responses against various pathogens while also establishing carefully regulated immune responses towards commensal bacteria. How exactly microbiota control the balance of pro-inflammatory and regulatory cellular immunity and its translation to anti-viral immunity is not well understood. To investigate the contribution of intestinal colonization to systemic anti-viral T cell immunity, this thesis examines germ-free and gnotobiotic mice colonized with precisely defined microbiotas using the Lymphocytic Choriomeningitis Virus (LCMV) infection model, and further explores how the specific antigenicity of gut commensals can influence T cell repertoire and function. Firstly, I demonstrated that gnotobiotic colonization improved the efficiency of T cell immunity, generating robust virus-specific responses from a T cell pool of limited activation. Secondly, using a commensal Escherichia coli colonization model I found that the presence of a single antigen within the microbiota can significantly alter T cell differentiation pathways, generating microbiota-specific regulatory T cells capable of suppressing systemic anti-viral immunity in a dose-dependent manner. This magnitude of this regulatory phenotype was further dependent on the complexity of microbial colonization, suggesting commensal-derived products reprogram T cells prior to viral infection. Altogether, the data in this thesis connects the intestinal microbiota to systemic T cell immunity through previously unknown mechanisms of antigen-specific regulation of anti-viral responses
Attitudes linguistiques des apprenants de français L2 de l’Université de Calgary
No full textS’inscrivant dans le champ de la sociolinguistique, cette recherche examine l’influence des attitudes linguistiques sur l’apprentissage du français langue seconde dans un contexte minoritaire. En s’appuyant sur les théories des représentations sociales développées notamment par Serge Moscovici et Jean-Claude Abric, l’étude analyse la manière dont les perceptions sociales du français influencent la motivation, l’engagement et la satisfaction des apprenants. Trois questions de recherche structurent cette enquête : (1) les attitudes linguistiques ont-elles une incidence sur l’apprentissage des langues ? (2) le français est-il perçu positivement ou négativement par les Calgariens ? et (3) la perception sociale d’une langue influence-t-elle la motivation des apprenants ? Les données analysées proviennent d’un questionnaire administré à des étudiants de premier cycle inscrits à des cours de français à l’Université de Calgary. L’analyse qualitative met en évidence plusieurs thèmes clés liés aux attitudes linguistiques, notamment le rôle des croyances sociétales, des stéréotypes, du stress, de la pression sociale et du contexte régional dans l’expérience d’apprentissage. Les résultats montrent que des attitudes positives envers le français favorisent la motivation, le plaisir d’apprendre et l’engagement à long terme, tandis que des perceptions négatives ou instrumentales peuvent entraîner un désengagement ou une frustration. L’étude souligne également l’importance des pratiques pédagogiques variées, du sentiment d’appartenance culturelle et de la valorisation des bénéfices pratiques et culturels du bilinguisme. En conclusion, cette recherche met en lumière le rôle central des attitudes linguistiques dans l’apprentissage du français et contribue à une meilleure compréhension des dynamiques sociolinguistiques qui façonnent l’enseignement et l’apprentissage des langues en contexte universitaire canadien
The Perceived Value of Open Educational Resources (OER) by Francophone Linguistic Minority Students in a Post-Secondary Educational (PSE) Setting
No full textIn most Canadian provinces, Francophone students are linguistic minority. French language academic resources are often more expensive, difficult to locate, and sometimes not available at all for niche subject areas. This often results in barriers to access learning materials. The unequal access to learning materials is an issue of equity and can potentially impact student success. The development and dissemination of French language open learning materials may assist in addressing this inequity. Open educational resources (OER) are open learning materials that are typically free and easy to access. The purpose of this qualitative research with case study methodology was to capture the experiences of Francophone students using French language OER in their courses or during their post-secondary education, and to thematically analyse these findings to better understand the benefits and challenges of using French language open learning materials. In this study I used semi-structured interviews with eight Francophone students to discuss their experience with French language OER. The eight individual interviews revealed some unique experiences among the participants as well as several recurring themes. A range of broad themes were developed from the data collected in the process of these interviews. These themes ranged from comments on the general characteristics of OER such as appreciating that OER were free and easy to access, criticisms about the lack of available French language OER and the poor quality of French, as well as emotional responses to the use of French language OER. Some participants also mentioned that they felt a sense of belonging with the larger global Francophone community by using French language OER
Strengthening public health political science: Utilizing policy process theory to examine fluoridation policy readoption in Calgary, Canada
No full textDespite the role of public policy in achieving a broader version of public health, there has been limited success in collaborative government decision making to improve the quality and equitable distribution of the social determinants of health in Canada. This is, in part, due to several challenges relating to Canada’s decentralized government structure, which reinforces a narrow version of public health. In this context, EIPH is promoted as a solution, yet there is a tendency for such models to inadequately account for or consider the complex processes of public health policymaking. To better account for complexity, there is value in considering tools, methods and insights from political science and public policy scholarship. In this dissertation, I use policy process theory to better understand public health policymaking, including the role of scientific evidence, via three conceptually linked research components: (1) a scoping review on the application of policy diffusion theory to public health policy; and a case study informed by the Multiple Stream Framework that examined (2) the readoption of community water fluoridation policy in Calgary, Alberta; and (3) how the interplay between uncertainty, ambiguity, and framing shaped scientific evidence use in that decision. Taken together, my results illustrate how traditional EIPH approaches risk obscuring the politics of scientific evidence use and production in uncertain and ambiguous public health policy arenas. Specifically, several different (and sometimes interacting) policy diffusion mechanisms can either facilitate or discourage the spread of public health policies between governments, with scientific evidence playing a limited role (Chapter 3). In addition, in my case study of fluoridation readoption in Calgary, scientific evidence did play a prominent role but its use and production were influenced by the alignment of local problem attention, the gradual acceptance of fluoridation as a solution through persuasive framing, and a receptive local political environment (Chapters 4 and 5). Overall, this dissertation demonstrates the value of examining contentious, ambiguous and uncertain public health policies such as fluoridation, via a public health political science approach, to better contextualize scientific evidence use and EIPH in the pursuit of improving the public’s health