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Adaptive Multi-Frame and Density Aware Fusion for 3D Reconstruction Using a Movable Stereo Sensor
No full textDepth perception is essential for robotic and spatial intelligence, yet conventional stereo systems are constrained by fixed baselines and static calibration. This research develops a movable stereo camera system that mimics the human eye through mechanical actuation and selective online calibration, enabling a broader and more adaptive field of view for dense three-dimensional reconstruction. A spectral-entropy based motion detection mechanism monitors overlap between consecutive frames and triggers recalibration only when required, reducing redundant computation while maintaining geometric accuracy. The system increases spatial coverage by up to 39% compared to fixed-baseline stereo and achieves precision within 5% error in static regions and 7 percent in extendedmovable ranges, comparable to commercial Intel RealSense sensors. Building on this hardware foundation, the research introduces a multi-frame 3D detection framework that integrates spatial and temporal reasoning through two modules applied sequentially: the Adaptive Density-based Region Voting (ADRV) mechanism for spatial adaptation, followed by the Probability-Based Proposal Feature Fusion (PPFF) module for temporal integration. ADRV adaptively re-weights local features based on point-density distributions to address sparsity in point clouds, while PPFF fuses object proposals across frames using probabilistic gating and attention-based weighting. Together, these modules enhance intra-frame representation and inter-frame consistency, strengthening detection robustness under motion and occlusion. Experiments on a custom movable-stereo indoor dataset and on public benchmarks such as ScanNet show that integrating ADRV and PPFF improves geometric completeness and increases 3D detection accuracy by up to 13.4%, 7%, and 2.9% mean average precision for baseline detectors including VoteNet, GroupFree3D, and V-DETR, respectively. Qualitative results demonstrate improved reconstruction of thin structures and spatial coherence across sequential frames. In summary, this thesis establishes a cohesive pipeline linking adaptive hardware sensing with density-aware multi-frame fusion. The approach provides a foundation for self-calibrating and learning-enhanced 3D perception, advancing the scalability of stereo vision for robotic mapping, inspection, and autonomous navigation in dynamic environments
Daily Parenting in Families of Adolescents with Fetal Alcohol Spectrum Disorder
No full textThere is a dearth of research examining the parenting characteristics and practices of caregivers of children and adolescents with fetal alcohol spectrum disorder (FASD). To meaningfully support these caregivers, it is essential to understand the factors that promote positive caregiver-child interactions in daily life. Despite growing awareness of the complex emotional, behavioural, and social challenges associated with parenting a child with FASD, relatively little is known about how parenting behaviours unfold in everyday contexts or how caregiver and child characteristics interact to shape these. Much of the existing literature focuses on child-level difficulties, with less attention paid to the caregiving environment or the strengths and adaptive strategies employed by families. This dissertation addresses these gaps by exploring both broader patterns and day-to-day variability in parenting behaviours among caregivers of adolescents with FASD. The first objective was to compare parenting dimensions (acceptance, psychological control, and behavioural/firm control) and their associations with caregiver well-being and adolescent functioning in caregivers of adolescents with and without FASD. Cross-sectional data from caregivers of adolescents with FASD (N = 37) and without FASD (N = 25) indicated that caregivers in the FASD group reported higher stress, anxiety, and depressive symptoms, as well as greater adolescent internalizing, externalizing, and sleep problems. Caregivers of adolescents with FASD also reported greater use of psychologically controlling (r = −.28, small effect) and firm parenting (r = .33, medium effect), whereas levels of acceptance did not differ between groups. The second objective examined daily variability in autonomy-supportive and psychologically controlling parenting behaviours in caregivers of adolescents with FASD using a 14-day daily diary design. Data from 20 caregivers revealed substantial within-person variability in parenting behaviours. On days when caregivers perceived more child conduct problems or hyperactivity, they reported less autonomy support and greater psychological control. Caregiver mood was also associated with parenting, such that positive mood was linked to greater autonomy support and negative mood to increased psychological control. Together, these findings highlight the dynamic, transactional nature of caregiving in families affected by FASD and identify important targets for family-based intervention
The Effect of Discrete In-Situ Consolidation on the Micro- and Macro-Structure of Additively Manufactured Continuous Fiber-Reinforced Thermoplastic Composites
No full textAdditive manufacturing of continuous carbon fiber-reinforced thermoplastics using fused filament fabrication (FFF) presents new opportunities for optimizing the design of thin shell structures, such as antenna reflectors and deployable booms for spacecraft. Despite these advantages, uptake of FFF has been hampered by poor mechanical properties brought on by poor consolidation. Discrete in-situ consolidation (DISC) of thermoplastic composites, a process by which a flat-bottomed heated tool applies localized heat and pressure along the length of each bead after deposition, is a promising strategy for improving the properties of parts made by FFF. However, the morphological changes at the micro- and macro-structural level induced by DISC are not well understood, limiting the accuracy of models used to predict the mechanical and thermomechanical behaviors of parts. Here, the effect of DISC processing parameters on individual beads is explored; DISC is found to cause significant bead spreading and thinning, as well as inducing a repeatable convex warpage in each individual bead, a phenomenon unique to this process. Through mechanical testing and microscopy, the effectiveness of DISC as an in-situ method for improving material quality is confirmed, with samples measured on average to have a void content of 0.016%. Specimens consolidated with DISC achieve tensile stiffness, tensile strength, and interlaminar shear strength on par with established conventional composite processing techniques i.e., compression molding. The changes in filament fiber morphology during DISC are explored with micro computed tomography and finite element modeling, revealing that uneven fiber packing in the filament cross-section after DISC is the cause of bead warpage. Finally, mechanical and thermomechanical models were developed, with the thermomechanical model incorporating the bead-level warpage observed. When applied to beads arranged in quasi-weave patterns, these models accurately predicted the mechanical response to tensile loading within 12% of experimental results. While the thermomechanical model was not as accurate in its predictions, the effect of processing effects was demonstrated to be vital to thermal warpage behavior. This work demonstrates that DISC performs well and resolves some of the shortcomings of FFF, and lays the groundwork for its use in designing and manufacturing load-bearing parts
Angiotensin II Receptor Type 1 Autoantibodies in Patients with Primary Aldosteronism
No full textIntroduction: Primary aldosteronism (PA) is a common cause of hypertension and is characterized by renin-independent aldosterone secretion. Determination of PA subtype (i.e., unilateral vs. bilateral) is clinically important to inform treatment. Immune mechanisms may have a role in the pathogenesis of PA. The aims of this study were to investigate the prevalence of AT1 autoantibodies in patients with PA, to explore whether they are differentially associated with the two main subtypes, and to determine if the presence of autoantibodies varies according to disease duration. Methods: We conducted a cross-sectional study of patients with PA who were referred through the regional Endocrine Clinic in Calgary, Alberta, Canada for adrenal vein sampling (AVS) from April 2023 to July 2024. We also included healthy controls (n=50). Patients and healthy controls had AT1 autoantibody titres measured. AT1 autoantibodies were defined as positive when >17 U/mL and negative if ≤17 U/mL. AVS was used as a standard to determine PA subtype. For the analysis, we estimated the prevalence of AT1 autoantibodies in patients with PA who were referred for AVS. Using multivariable logistic regression, we determined whether AT1 autoantibodies were independently associated with the subtype of PA, after adjusting for other major clinical predictors. And, we examined for whether the presence of AT1 autoantibodies was independently associated with duration of disease. Results: 105 patients with PA (mean age, 53.1 years; 45.7% male), and 50 healthy controls (mean age, 47.4 years; 50.0% male) were included. Positive AT1 autoantibodies were present in 23.0% (24) of patients with PA compared to 10.0% (5) of people who were healthy, and this difference bordered on statistical significance (p=0.055). Ninety-nine patients with successful AVS were included to examine if the AT1 autoantibodies predict the subtype of PA. Higher AT1 autoantibody levels were independently associated with lateralization, indicating unilateral PA (OR, 1.05; 95% CI, 1.00-1.11; p=0.047), after adjusting for other major clinical predictors. No correlation was found between AT1 autoantibodies and duration of disease. Discussion: In this study AT1 autoantibodies were found to be present in 23% of people with PA compared to 10% in the general population. AT1 autoantibodies were also found to be associated with lateralizing disease, but not disease duration. Overall, AT1 autoantibodies are common in patients with PA and may be helpful for stratifying patients according to PA subtype
Impaired systemic antibody response against gut microbiota pathobionts in critical illness and susceptibility to nosocomial infections
No full textAbstract Background Critically ill patients in intensive care units (ICUs) experience high rates of hospital-acquired (nosocomial) infections, commonly caused by translocation and dissemination of pathogenic microorganisms that colonize the intestinal tract (pathobionts). Multiple immune barriers protect the host against commensal and pathogenic colonizers, including a repertoire of circulating anti-commensal antibodies. The integrity of this systemic antibody-mediated defense system, its relationship with gut microbiota dysbiosis, and its impact on nosocomial infections in the ICU have not been explored. Results We performed a longitudinal cohort study of 46 critically ill patients at day 1 and day 3 of their ICU admission compared to 28 healthy volunteer controls. Circulating IgM, IgG, and IgA responses against 10 common gut and extra-intestinal pathobionts were quantified by flow cytometry, together with high-dimensional analyses of circulating B cell populations, fecal microbiota composition, and clinical outcomes. We observed reduced plasma IgM and IgG reactivity against intestinal pathobionts such as Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis in ICU patients compared to healthy volunteers. Reduced gut pathobiont antibody responses in ICU patients was associated with B cell lymphopenia, and patients with gut microbiota dysbiosis had reduced levels of natural antibody producing B1-like B cells. Reduced IgG and IgM reactivity against gut Gram-negative pathobionts was associated with an increased risk of nosocomial infection or death. Conclusions These findings indicate that the systemic antibody barrier against microbiota pathobionts is compromised in critical illness and associated with increased risk of nosocomial infections
All providers Better Communication Skills (ABCs) program: protocol for a randomized controlled trial assessing communication training effectiveness with interprofessional clinicians
No full textAbstract Background High-quality person-centred communication for those living with serious illness benefits patients, families, and health care professionals (HCPs). However, research suggests that HCPs often find it challenging to engage in these discussions. The purpose of this study is to assess the effectiveness of the ‘All providers Better Communication Skills’ (ABCs), an online blended learning program delivered over three months. The ABCs program seeks to complement existing programs by adopting an interprofessional and person-centred educational philosophy, teaching core communication skills that can be utilized by any clinician across many conversations and healthcare settings, and investigating outcomes focused on clinician’s skill acquisition and behavior change. Methods We will conduct a Canada-wide prospective stepped-wedge randomized controlled trial with interprofessional HCPs. All participants will receive the intervention, however, there will be a delay in the intervention for those randomly assigned to the control group. Our study will measure change in pre and post intervention scores for all participants. The primary outcome consists of external expert rater assessments of participants’ video-recorded Standardized Patient (SP) encounters using the validated Assessment of Clinical Encounters – Communication Tool. Secondary outcomes include: participant self-assessments on self-efficacy using the validated Self-Efficacy-12 measure, as well as competence using the Patient and Family-Centered Communication subscale from the validated End-of-Life Professional Caregiver Survey; and SP ratings using the validated Questionnaire on the Quality of Physician-Patient Interaction and Feeling Heard and Understood measures. Learning experience and perceived usability of the program will also be assessed through the validated Blended Learning Usability Evaluation – Questionnaire and semi-structured interviews following program completion. Discussion This study is a national trial evaluating the effectiveness of a communication program for interprofessional HCPs. This research will generate evidence on ways of improving conversations about serious illness. With improved communication skills, clinicians can better support patients and families in their illness understanding, deliver care that better aligns with their patients’ goals and values, improve care-related outcomes and experiences, and optimize healthcare resources – all of which can support health system strengthening. Trial registration https://clinicaltrials.gov/study/NCT06606470
Clinical Trial Eligibility in Atopic Dermatitis: Data from a Large Real-World International Cohort
No full textAbstract Introduction Randomized clinical trials (RCTs) in atopic dermatitis (AD) often exclude older adults and patients with comorbidities, limiting the generalizability of trial findings to real-world populations. Despite the growing use of biologics and Janus kinase inhibitors (JAKis) in clinical practice, the extent to which real-world patients meet RCT eligibility criteria and their associated safety outcomes remains unclear. Methods We conducted a retrospective analysis of a large, multicenter international cohort of adolescents and adults with AD treated with biologics (dupilumab, tralokinumab) or systemic JAKis (abrocitinib, baricitinib, upadacitinib) between October 2017 and March 2023 across 16 dermatology centers. Eligibility was defined according to commonly applied RCT criteria. Patients meeting ≥ 1 exclusion criterion were classified as ineligible. Demographic, clinical, and safety outcomes were analyzed. Results Among 2154 patients, 514 (23.9%) were ineligible. The most frequent reasons were Eczema Area and Severity Index (EASI) < 16 (67.9%), age ≥ 75 years (21.8%), and cardiovascular disease (13.0%). Ineligibility patterns differed across treatments: patients receiving JAKis were most often ineligible because of EASI < 16 (92.8%), whereas ineligibility among biologic users more commonly reflected also age or cardiovascular comorbidity. Ineligible patients were older, had more non-atopic comorbidities, and had lower measured baseline disease activity. Safety profiles were generally favorable. Among biologic-treated patients, adverse event rates were similar between eligible and ineligible groups. In the JAKi cohort, overall adverse events were more frequent in ineligible patients (52.9% vs. 42.6%; p = 0.051), with acneiform eruption and lipid abnormalities emerging as the most distinct differences. No unexpected safety signals were identified in either treatment group. Conclusion Nearly one-quarter of real-world patients with AD would not have met eligibility criteria for pivotal RCTs, yet both biologics and JAK inhibitors demonstrated acceptable safety profiles in these populations. While adverse events were more frequent among ineligible patients receiving JAKis, findings require further investigation to determine their clinical relevance, particularly regarding long-term cardiovascular outcomes
Persistence, switching, and healthcare use after initiating calcitonin gene-related peptide inhibitors: a real-world assessment
No full textAbstract Background Migraine is a prevalent and disabling condition affecting one billion people worldwide. calcitonin gene-related peptide (CGRP) inhibitors have transformed migraine management. We describe real-world trends in CGRP inhibitor treatment, switching, discontinuation, and migraine-related health care use (including emergency department, ED, and ambulatory care visits). Methods We used the Merative™ MarketScan® Research data, providing data on inpatient and outpatient healthcare use and drug dispensation from a large sample of individuals with employer-sponsored health insurance in the United States. We identified adults using CGRP inhibitors (comprising both monoclonal antibodies, mAbs, and small-molecule CGRP receptor antagonists, gepants) as preventive treatment for migraine between May 2018 and December 2022. We evaluated treatment patterns, including switching between CGRP agents or other prophylactic migraine treatments, and therapy discontinuation. Healthcare and migraine-related medication use were compared one year pre- and post-CGRP inhibitor initiation. Migraine-related medications included preventive migraine-specific treatments (e.g., onabotulinumtoxinA), non-specific preventives (e.g., antidepressants), and acute treatments—both migraine-specific (e.g., triptans) and non-specific (e.g., opioids). Results We studied 148,100 adults with at least one CGRP inhibitor dispensation. CGRP inhibitor use increased over time, with newer agents being more commonly dispensed in recent years. Within the first year, 10.3% of individuals switched between CGRP inhibitors, and an additional 13.5% discontinued their first CGRP inhibitor without switching to another. Post-initiation, there was a 4.5% reduction in migraine-related medication use (95% confidence interval, CI: -4.9% to -4.0%, and 12.8% reduction in healthcare use (95% CI: -13.2% to -12.3%). Conclusions CGRP inhibitors are increasingly used over time. About 10% switch between CGRP agents within the first year of initiation. There was reduction in other migraine-related medications and healthcare visits following CGRP initiation. Trial registration N/A
Investigating the Role of Glucagon-Like Peptide-1 in the Regulation of Spermatogenesis in Adult Danio rerio (Zebrafish)
No full textGlucagon-like peptide-1 (GLP-1) is a product of post-translational modification to the proglucagon peptide produced by the enteroendocrine L-cells and the central nervous system. There is evidence that GLP-1 has broad physiological functions, including glucose-dependent stimulation of insulin secretion, reduction of gastric emptying and food intake, as well as having cardio- and neuroprotective effects. GLP-1 has also been shown to reduce the inflammatory response and apoptosis, and to be involved in the control of learning, memory, and reward behaviour. Currently, GLP-1 receptor agonists are in clinical use for the treatment of type 2 diabetes, obesity, and neurodegenerative disorders. More recently, studies have shown evidence for expression of the GLP-1 receptor in human and rodent testes, specifically within Leydig cells. However, no information is available on the direct action of GLP-1 on spermatogenesis. Using an ex vivo testis tissue culture system unique to zebrafish, we were able to study the direct effect of GLP-1 on spermatogenesis. Our results provide novel evidence for the presence of GLP-1 receptor and proglucagon, a GLP-1 precursor, within zebrafish testis tissue. Direct action of GLP-1 was tested on basal and LH (hCG)-induced spermatogenesis from spermatogonia stem cells to spermatozoa. Treatment with increasing concentrations of GLP-1 did not alter the basal and hCG-induced spermatogenesis in the zebrafish testis. These ex vivo findings in a zebrafish model contribute supportive evidence consistent with the current absence of reported testicular safety issues associated with therapeutic use of GLP-1 agonists in males
Day-of-surgery quality gaps in glycemic management: a retrospective cohort study
No full textAbstract Background Perioperative hyperglycemia is associated with worse patient outcomes. Characterizing quality gaps in day-of-surgery glucose management can guide quality improvement teams to address this risk factor for infection, readmission, and death. Methods This retrospective cohort study used administrative and electronic health record data to describe process, outcome, and balancing measures of day-of-surgery glycemic management for adult patients with and without diabetes undergoing surgery at 6 hospitals in Alberta, Canada between 2019 and 2024. Participants were stratified by diabetes, prediabetes, no diabetes and unknown diabetes status. We report the association between hyperglycemia (blood glucose ≥ 10.0 mmol.L−1) and length of stay, admission to ICU, and 30-day readmissions as an exploratory analysis. Results There were 12,275 eligible procedures including 3,164 procedures performed on patients with diabetes (25.8%). Of patients with diabetes, 85.4% (n = 2,703) had at least one glucose measurement on the day of surgery and 37.1% (n = 1,004) had hyperglycemia. About half of patients with diabetes and hyperglycemia received insulin (51.4%, n = 516). More than 10% of patients with prediabetes, no diabetes, and unknown diabetes status had hyperglycemia and less than 20% received insulin. Patients with hyperglycemia on the day of surgery had longer length of stay (4.49 days; 95% CI 4.70 to 5.18 days; p < 0.0001), postoperative ICU admission (aOR 5.37; 95% CI 4.45–6.49; p < 0.001) and odds of 30-day readmission (aOR 2.19; 95% CI 1.89–2.54; p < 0.0001). Conclusions There were important quality gaps in glucose measurement and hyperglycemia treatment for patients with diabetes. Hyperglycemia was common and clinically significant among patients without diabetes. Future work to understand the prevalence of hyperglycemia in patients without diabetes and to address quality gaps in day-of-surgery glucose measurement are needed