electronic theses and dissertations from 2009 - 阿根廷vs墨西哥竞猜

factors impacting the referral to, enrollment in, and completion of cardiac rehabilitation within northwest, ontario

2024-01-01t00:00:00z

factors impacting the referral to, enrollment in, and completion of cardiac rehabilitation within northwest, ontario lamarche, dallon t. northwest ontario has higher rates of cardiac hospitalization compared to southern ontario for reasons not fully understood. however, cardiac rehabilitation (cr), a proven secondary prevention strategy, remains underutilized in northwest ontario. this study therefore aims to evaluate cr utilization and factors that impact access to cr. we also examined how cr may impact cardiac-related rehospitalization in northwest ontario. methods: a retrospective cohort study was selected to analyze patients discharged with a cardiac-related index event at the thunder bay regional health sciences centre (tbrhsc) between july 2014 and december 2017 and subsequently followed until february 2023. binary logistic regression and cox proportional hazards models were used to identify factors influencing cr referral, enrollment, completion, and time to cardiac-related rehospitalization. findings: of the 448 eligible patients, 93.1% were referred to cr, of those only 51.7% enrolled, and of those that enrolled about 41.9% completed the program. the overall completion rate from the 448 eligible patients was therefore 19.9%. enrollment was positively associated with having a partner (or=3.14, p<0.01) and being female (or=2.06, p<0.01) and negatively with drive time (or=0.97, p=0.03). a family history of heart disease was the only factor associated with cr completion (or=2.18, p=0.02). cr completion delayed time to rehospitalization (hr=0.69, p=0.05), with a 31% lower risk of rehospitalization among those completing cr in our unadjusted analysis. however, after adjusting for covariates, this impact became non-significant. conclusion: although referral rates are high due to a systematic process at the tbrhsc, cr enrollment and completion in northwest ontario remain suboptimal. barriers include gender disparities and geographic accessibility. while completing cr appears to reduce cardiac-related rehospitalization, the overall impact on mitigating the cardiovascular disease burden in northwest ontario may be limited due to low cr completion rates. further research is needed to quantify the long-term benefits of cr completion and identify strategies to improve completion rates in this region.

development of an advanced thermal imaging-based human fall detection system

2024-01-01t00:00:00z

development of an advanced thermal imaging-based human fall detection system silver, christopher falls represent a significant risk to the elderly population, often leading to severe injuries or fatalities. automatic fall detection systems (fds) are critical for mitigating these risks; however, existing solutions, despite reporting accuracies in controlled environments, often fail to generalize to real-world conditions. this performance gap stems from limitations in existing datasets, overfitted models, and a lack of standardization. to address these challenges, this thesis presents a comprehensive framework for fall detection, leveraging privacy-preserving thermal imaging to develop deployable, real-world solutions. the research is conducted in three progressive phases. the first phase explores a novel hybrid architecture that combines supervised and unsupervised learning paradigms through a stacking ensemble of 3d convolutional neural networks (3d cnns) and autoencoders (aes). this hybrid approach demonstrates significant performance improvements on constrained datasets, highlighting its potential in scenarios where fully supervised methods fall short. ablation studies validate the architecture’s utility while underscoring the critical need for a more robust dataset to achieve true generalizability. in the second phase, the thesis introduces thermal fall 66 (tf-66), the most diverse and comprehensive thermal fall detection dataset to date. designed to address the limitations identified in phase 1, tf-66 encompasses varied environments, participant demographics, and fall scenarios. accompanied by targeted subsets and flexible data generators, tf-66 serves as a benchmark for meaningful comparisons and standardized evaluations, advancing the field toward real-world applicability. the third phase synthesizes insights from the hybrid approach and tf-66 dataset to refine a supervised 3d cnn model. enhanced with innovative features such as optical flow integration and attention mechanisms, this model achieves state-of-the-art performance on tf-66 and the widely used thermal simulated fall (tsf) dataset. by bridging the gap between lab-optimized systems and real-world demands, this final phase establishes a transformative approach to fall detection, redefining the state of fall detection research, with a focus on generalizable systems that can operate in real-time. the findings provide a clear path for developing accurate, privacy-preserving, and scalable fall detection systems, ultimately aiming to enhance the safety and save lives of seniors worldwide.

wetlands as filters of heavy metals: a study in temperate fens of central ontario

2024-01-01t00:00:00z

wetlands as filters of heavy metals: a study in temperate fens of central ontario koornneef, karen heavy metal concentrations (as, cd, cr, cu, ni, pb, and zn) were investigated in water, peat, and macrophytes across three fens in central ontario in relation to the water parameters and peat properties to elucidate the interactions between plant sequestration and heavy metal concentrations in the overlying water systems. the water parameters monitored include ph, dissolved oxygen, conductivity, total dissolved solids, salinity, nutrients, chlorophyll a, and dissolved organic matter. the peat properties studied included bulk density, volumetric porosity, and humification, and the plant properties studied included root length and the development of root plaques. in addition, all samples were analyzed for heavy metals. the fens were categorized from poor to rich depending on their water chemistry and plant community. surface water samples were collected from the inlet, outlet and midpoint of the fens in the spring, summer, and fall of 2023. porewater samples were collected from the midpoints of the fens using in situ pore water sampling device. in situ pore water sampling devices were deployed in the peat, and the porewater samples were collected from 10, 20 and 30 cm below the peat surface. peat cores were also collected in fall 2023 from the inlet and the midpoints of the fens to analyze the peat properties and heavy metal concentrations at three different depths (10, 20, and 30 cm below the peat surface). additionally, 13 plant species were collected in fall 2023 from the fens' midpoints and divided into upper and lower biomass for heavy metal analysis. [...]

do common over-the-counter antihistamine medications modify thermoregulatory responses during passive heat stress?

2024-01-01t00:00:00z

do common over-the-counter antihistamine medications modify thermoregulatory responses during passive heat stress? newhouse, douglas a. over the coming decade, climate change is expected to increase the duration and intensity of pollen season and contribute to higher atmospheric concentrations of inhaled allergens (corden & millington, 2001; d’amato et al, 2015). this is likely to increase the number of individuals who suffer from respiratory conditions such as allergic rhinitis (ar), worsen their symptoms, and stress healthcare infrastructure (beggs, 2004; kim et al, 2018; ziska & caulfield, 2000; ziska et al, 2019). currently, guidance suggests all antihistamines may increase an individuals’ risk of heat-related illness/injury (hri) during heat stress by suppressing human thermoeffector responses (casa et al, 2015; coco et al, 2016; osha, 2011; o’connor & degroot, 2024; roberts et al, 2023; who, 2011). however, whether over-the-counter (otc) antihistamines for allergy, taken as recommended, alter sudomotor and/or cardiovascular responses during heat stress has not been critically analyzed in humans. this thesis sought to determine whether the oral ingestion of three common otc antihistamines (diphenhydramine, loratadine & desloratadine) would alter sudomotor, cardiovascular, or perceptual responses to heat stress when compared to a placebo pill (sugar). a total of 10 young healthy participants (5m, 5f, 22.6 ± 1.8 yrs, 174 ± 10 cm, 73.6 ± 10.8 kg) completed our double-blind randomized crossover procedure where they consumed either i) 50 mg diphenhydramine ii) 10 mg loratadine iii) 5 mg desloratadine or iv) a sugar pill before being passively heated to a mean body temperature 1.5℃ above baseline. preliminary data suggests that otc antihistamines do not alter local sweat rate of the forearm [mg/cm2/min1 (placebo (pla): 0.411, diphenhydramine (dph): 0.436, loratadine (lor): 0.368, desloratadine (des): 0.432)], skin blood flow [%max (dph: 25.71, lor: 21.81, des: 21.10, pla: 21.27)], heart rate [bpm (dph: 72.25, lor: 78.34, des: 74.86, pla: 74.94)], mean arterial pressure [mm/hg (dph: 81.95, lor: 82.09, des: 82.20, pla: 80.98)], or rate-pressure product [mm/hg (dph: 8604, lor: 9051, des: 9126, pla: 8851)] during passive heating, suggesting they may continue to be a safe option to allergic symptom management during periods of heat exposure. further research aimed at examining different otc antihistamines and/or doses, in other heat-vulnerable groups and types of heat stress is required to wholly conclude the hri risk posed by otc antihistamines.