Digital Commons Network^™

The Developmental Importance Of Napping In Preschool Children, Adam T. Newton

Electronic Thesis and Dissertation Repository

Most children cease napping between 2- and 5-years-old. Little is known about the predictors or outcomes related to this cessation, or the interrelation of different components of nap behavior. Four empirical studies were conducted to investigate the developmental importance of napping among preschool children.

Studies 1 and 2 used a large, longitudinal sample of Canadian children to investigate the predictors (Study 1) and outcomes (Study 2) related to early nap cessation. Early nap cessation was defined as stopping daytime sleep before three years old. In Study 1, parents reported on their own, child, and family functioning at two timepoints (0-1 …

Motor Vehicle Collisions In London, Ontario: Estimating The Influence Of The Built Environment And Children’S Potential Exposure, David Lui

Electronic Thesis and Dissertation Repository

Motor vehicle collisions are the leading cause of death for children and youth worldwide. To effectively target interventions to improve child safety, it is necessary to identify where motor vehicle collisions occur most often and what factors make these areas more hazardous. Study #1 maps collisions in London, Ontario (2010-2019) and identifies hotspots using a network kernel density estimation method within a GIS. Logistic regression analysis revealed that bike lanes were negatively associated with hotspots, while sidewalks were positively associated. Study #2 estimated children’s risk of being exposed to a motor vehicle collision while commuting to and from school, by …

Oral Anticoagulant Decreases Stroke Recurrence In Patients With Atrial Fibrillation Detected After Stroke, Jin Yi Hsu, Peter Pin Sung Liu, Luciano A. Sposato, Huei Kai Huang, An Bang Liu, Edward Chia Cheng Lai, Swu Jane Lin, Cheng Yang Hsieh, Ching Hui Loh

Neuroscience Institute Publications

Background: Atrial fibrillation detected after stroke (AFDAS) has a lower risk of ischemic stroke recurrence than known atrial fibrillation (KAF). While the benefit of oral anticoagulants (OAC) for preventing ischemic stroke recurrence in KAF is well established, their role in patients with AFDAS is more controversial. This study aimed to evaluate the association between OAC use and the risk of recurrent ischemic stroke in patients with AFDAS in a real-world setting. Methods: This nationwide retrospective cohort study was conducted using the Taiwan National Health Insurance Research Database. Patients hospitalized with a first-ever ischemic stroke and AFDAS confirmed within 30 days …

Patterns And Trends Among Physicians-In-Training Named In Civil Legal Cases: A Retrospective Analysis Of Canadian Medical Protective Association Data From 1993 To 2017, Allan Mcdougall, Cathy Zhang, Qian Yang, Taryn Taylor, Heather K. Neilson, Janet Nuth, Ellen Tsai, Shirley Lee, Guylaine Lefebvre, Lisa A. Calder

Obstetrics & Gynaecology Publications

BACKGROUND: Medico-legal data show opportunities to improve safe medical care; little is published on the experience of physicians-in-training with medical malpractice. The purpose of this study was to examine closed civil legal cases involving physicians-in-training over time and provide novel insights on case and physicians characteristics. METHODS: We conducted a retrospective descriptive study of closed civil legal cases at the Canadian Medical Protective Association (CMPA), a mutual medico-legal defence organization for more than 105 000 physicians, representing an estimated 95% of physicians in Canada. Eligible cases involved at least 1 physician-in-training and were closed between 1993 and 2017 (for time …

Social Determinants Of Stroke Hospitalization And Mortality In United States’ Counties, Randhir Sagar Yadav, Durgesh Chaudhary, Venkatesh Avula, Shima Shahjouei, Mahmoud Reza Azarpazhooh, Vida Abedi, Jiang Li, Ramin Zand

Neuroscience Institute Publications

(1) Background: Stroke incidence and outcomes are influenced by socioeconomic status. There is a paucity of reported population-level studies regarding these determinants. The goal of this ecological analysis was to determine the county-level associations of social determinants of stroke hospitalization and death rates in the United States. (2) Methods: Publicly available data as of 9 April 2021, for the socioeconomic factors and outcomes, was extracted from the Centers for Disease Control and Prevention. The outcomes of interest were “all stroke hospitalization rates per 1000 Medicare beneficiaries” (SHR) and “all stroke death rates per 100,000 population” (SDR). We used a multivariate …

The Analysis Of Mark-Recapture Data With Individual Heterogeneity Via The H-Likelihood, Han-Na Kim

Electronic Thesis and Dissertation Repository

Mark-recapture methods play a key role in ecological studies monitoring wild animal populations. One consideration in analyzing mark-recapture data is individual variation in the detection rate. Classical methods for modelling heterogeneity require numerical integration and may be computationally intensive. This thesis presents a novel approach based on the h-likelihood to remedy such difficulties by avoiding numerical integration.

First, I present the h-likelihood approach for fitting the fundamental model describing individual heterogeneity in mark-recapture studies. The conditional likelihood approach allows the model to be regarded as a generalized linear mixed model (GLMM). I construct the h-likelihood for the model in the …

Using Conservation Genetics To Inform Reintroduction Of The Endangered Mottled Duskywing (Erynnis Martialis), Shayla Kroeze

Electronic Thesis and Dissertation Repository

Habitat loss and climate change have caused declines in species diversity and abundance globally, including in butterflies which are important components of many ecosystems. Reintroductions are increasingly used to reverse diversity loss but are most effective when informed using genetics. I developed 24 microsatellites and characterized genetic structure and diversity of the endangered Mottled Duskywing (Erynnis martialis) in Ontario and neighbouring provinces and states. These were used to inform a planned reintroduction in Ontario. Populations had moderate levels of genetic diversity, however all but the largest populations may be subject to appreciable levels of genetic drift. Populations more …

The Effect Of Interprofessional Conflict Resolution On Interprofessional Collaborative Practice Among Health Care Provider Teams In Hospitals, Sibylle Ugirase

Electronic Thesis and Dissertation Repository

Client needs and their complexities have increased, challenging multiple professionals to work together within health systems to reach better patient outcomes. Addressing this challenge requires interprofessional collaboration, which, while essential, may also breed conflict given that individuals from various health care disciplines each bring their unique perspectives into teamwork. While some degree of disagreement is expected, team members must be able to resolve conflicts to ensure effective patient care. However, limited information was available that described and clearly defined interprofessional conflict resolution as a concept.

The aim of this study was threefold. This study began with a concept analysis of …

The Incidence Of Psychotic Disorders And Area-Level Marginalization In Ontario, Canada: A Population-Based Retrospective Cohort Study, Martin Rotenberg, Andrew Tuck, Kelly K. Anderson, Kwame Mckenzie

Paediatrics Publications

Background: There is limited Canadian evidence on the impact of socio-environmental factors on psychosis risk. We sought to examine the relationship between area-level indicators of marginalization and the incidence of psychotic disorders in Ontario. Methods: We conducted a retrospective cohort study of all people aged 14 to 40 years living in Ontario in 1999 using health administrative data and identified incident cases of psychotic disorders over a 10-year follow-up period. Age-standardized incidence rates were estimated for census metropolitan areas (CMAs). Poisson regression models adjusting for age and sex were used to calculate incidence rate ratios (IRRs) based on CMA and …

Teaching Note On Indigenous Peoples And The Land, Marek Brooking

2022 Cohort

During my Head & Head Fellowship journey, I was tasked with creating a Teaching Note on the legal aspects of Indigenous land, which primarily discusses how centuries of colonialism has influenced the way that Indigenous land is treated in Canada and by extension what could be done to reconcile with these past injustices. This presentation shall not only touch upon the project itself, but also many other aspects of my journey that had to be addressed when discussing an issue that is often overlooked in modern Canadian society. For example, the concept of respect, responsibility, and relevance when discussing an …

Fear Of The Human "Super-Predator" In African Mammals, Nikita R. Frizzelle

Electronic Thesis and Dissertation Repository

Humans’ exploitive killing of virtually every mammal species globally may result in a perception of humans as feared, ultra-lethal predators. In Africa, mammals are central to the continent’s tourism industry; however, it is largely unknown whether African mammals fear the presence of tourists. Firstly, I aimed to review how the presence of humans on the landscape affects African mammal behaviour. Of 31 studies, most authors reported that humans alter mammal behaviour in a manner that may negatively impact survival. To test if a fear of humans can pervade communities, I simulated the presence of humans, hunting, lions, and birds using …

Investigating Social Dynamics Using Automated Radiotracking Of Winter Flocks Of Black-Capped Chickadees (Poecile Atricapillus), Christopher J. Course

Electronic Thesis and Dissertation Repository

The major forces that govern social groups, namely fission-fusion dynamics, cohesion and maintenance, are nearly ubiquitous across animal groups. The field of animal collective behaviour has recently been married with automated radiotracking producing a ‘re-wilding’ of field research into sociality. The combination of this with Social Network Analysis has led to discoveries such as population wide information transfer and the flexibility of animal groups to change social connectivity based on environmental context. However, these networks are constructed, and do not include the dynamic environmental, spatio-temporal, and social contexts which directly affect sociality. I conducted the first automated radiotracking study I …

Inter-Disciplinary Characterization Of Streambed Heterogeneity And Its Influence On Groundwater-Stream Water Interactions, Kyle Robinson

Electronic Thesis and Dissertation Repository

It is well recognized that groundwater-surface water interactions influence the quantity and quality of various hydrogeological systems (rivers, lakes, streams). Groundwater-stream systems are an important investigative area for understanding fate and transport of nutrients and chemicals within the stream. While traditional methodologies are established to provide measurement and mapping of the spatial distribution of groundwater-stream interactions and exchange fluxes across a streambed, many can be invasive, labour intensive and suffer from low sampling density. The complexity in such systems is due largely to the heterogeneous nature both spatially and temporally. Given the strong control by streambed lithology on groundwater-surface water …

Extreme Heat And Paediatric Emergency Department Visits In Southwestern Ontario, Piotr Wilk, Anna Gunz, Alana Maltby, Tharsha Ravichakaravarthy, Kristin K. Clemens, Éric Lavigne, Rodrick Lim, Ana Maria Vicedo-Cabrera

Paediatrics Publications

Objective: The risk of adverse health events is expected to increase with hotter temperatures, particularly among the most vulnerable groups such as elderly persons and children. The objective of this study was to assess the association between extreme heat and daily emergency department visits among children (0 to 17 years) in Southwestern Ontario. Methods: We examined the average maximum temperature, relative humidity, and daily paediatric emergency department visits in June through August of 2002 to 2019. We reviewed emergency department visits from two academic hospitals. Daily meteorological data from the local weather station were obtained from Environment and Climate Change …

Incidence Of Cancer And Stage At Diagnosis Among People With Recent-Onset Psychotic Disorders, Jared C. Wootten

Electronic Thesis and Dissertation Repository

Evidence on cancer incidence in people with psychotic disorders, compared to the general population, is equivocal, although those with psychotic disorders so have more advanced stage of cancer at the time of diagnosis. The objective of this thesis was to compare cancer incidence and stage at diagnosis for people with psychotic disorders, relative to the general population. Our systematic review did not observe a significant difference in overall cancer incidence among people diagnosed with psychotic disorders (RR = 1.08, 95% CI: 1.00 to 1.16), however people with psychotic disorders were more likely to be present with advanced stage cancer at …

Describing Functional Brain Connectivity's Role In The Relationship Of Multimodal Interventions To Improve Cognitive And Physical Function In Vulnerable (Frailty & Mild Cognitive Impairment) Older Adults., Nicholas (Nick) W. Bray

Electronic Thesis and Dissertation Repository

Aging is associated with declining cognitive and physical function. The decline accelerates in older adults diagnosed with mild cognitive impairment (MCI), a pre-dementia state, and frailty, a state of decreased physiological reserve. Previous work shows that frailty modifies the relationship between dementia pathology and clinical symptoms. Functional brain network connectivity (FBNC) refers to brain areas that are anatomically separate but temporally related in their neural signaling; it is believed to enable the completion of complex cognitive and physical functions. FBNC is considered a sensitive biomarker for monitoring the progression of dementia syndromes and investigating the efficacy of interventional strategies. Therefore, …

Uganda As A Role Model For Pandemic Containment In Africa, Ahmed M. Sarki, Alex Ezeh, Saverio Stranges

Epidemiology and Biostatistics Publications

No abstract provided.

Maternal And Neonatal Mortality Associated With Caesarean Section, Areej A. Hezam

Electronic Thesis and Dissertation Repository

Universal access to safe caesarean section is vital. The objective of this thesis was to quantify the risks of maternal and neonatal mortality, and causes of caesarean-related deaths.

Our initial systematic overview of pre-existing meta-analyses found no interventions that significantly reduced the risk of all-cause maternal or neonatal mortality. However, many interventions have been understudied.

Our systematic review and meta-analysis of 196 studies identified that the risk of perioperative maternal mortality has decreased over time and according to country development index, and the risk of perioperative neonatal mortality has fluctuated. We also found that the proportion of reported causes of …

Area-Level Variation In Children’S Unmet Need For Community-Based Mental Health Services: Findings From The 2014 Ontario Child Health Study, Laura Duncan, Katholiki Georgiades, Graham J. Reid, Jinette Comeau, Stephen Birch, Li Wang, Michael H. Boyle

Paediatrics Publications

There is limited empirical evidence documenting the magnitude and correlates of area-level variability in unmet need for children’s mental health services. Research is needed that identifies area-level characteristics that can inform strategies for reducing unmet need in the population. The study purpose is to: (1) estimate area-level variation in children’s unmet need for mental health services (using Service Areas as defined by the Ontario Ministry of Children and Youth Services), and (2) identify area-level service arrangements, and geographic and population characteristics associated with unmet need. Using individual-level general population data, area-level government administrative data and Census data from Ontario, Canada, …

After-Hours Incentives And Emergency Department Visits: Evidence From Ontario Forthcoming At Canadian Public Policy, Rose Anne Devlin, Koffi Ahoto Kpelitse, Lihua Li, Nirav Mehta, Sisira Sarma

Epidemiology and Biostatistics Publications

No abstract provided.

Tracing Nutrient Sources To Lipid Production In Birds And Insects Using Stable Isotope (Δ13c, Δ2h) Tracers: Implications For Nutritional Physiology Of Migratory Species, Libesha Anparasan

Electronic Thesis and Dissertation Repository

Using stable isotope measurements of inert tissues to determine origins and migratory patterns is well established. However, isotopically determining nutritional origins of lipids, the primary fuel of migration, has not been attempted. I explored isotopic links between diet and stored lipids in captive White-throated Sparrows (Zonotrichia albicollis) and true armyworm moths (Mythimna unipuncta) using δ¹³C and δ²H measurements. Isotopic discrimination between body lipids and diet was established as linear calibration functions. Isotopic uptake following a diet switch in moths was used to trace lipid accumulation over time. Isotopic correlations between breath metabolic …

Exploring The Estimability Of Mark-Recapture Models With Individual, Time-Varying Covariates Using The Scaled Logit Link Function, Jiaqi Mu

Electronic Thesis and Dissertation Repository

Mark-recapture studies are often used to estimate the survival of individuals in a population and identify factors that affect survival in order to understand how the population might be affected by changing conditions. Factors that vary between individuals and over time, like body mass, present a challenge because they can only be observed when an individual is captured. Several models have been proposed to deal with the missing-covariate problem and commonly impose a logit link function which implies that the survival probability varies between 0 and 1. In this thesis I explore the estimability of four possible models when survival …

A Comparative Analysis Of The Restaurant Consumer Food Environment In Rochester (Ny, Usa) And London (On, Canada): Assessing Children’S Menus By Neighbourhood Socio-Economic Characteristics, Catherine Dubreck, Richard C. Sadler, Godwin Arku, Jamie A. Seabrook, Jason A. Gilliland

Human Environments Analysis Lab (HEAL)

Objective:To assess restaurant children’s menus for content and nutritional quality; and to investigate the relationship between the restaurant consumer food environment for children and neighbourhood-level socio-economic characteristics within and between one Canadian city and one US city. Design: Cross-sectional observational study. Setting: London, ON, Canada and Rochester, NY, USA. Participants: Restaurant children’s menus were assessed, scored and compared using the Children’s Menu Assessment tool. We quantified neighbourhood accessibility to restaurants by calculating 800 m road-network buffers around the centroid of each city census block and created a new Neighbourhood Restaurant Quality Index for Children (NRQI-C) comprising the sum of …

Involuntary Hospitalization Among Young People With Early Psychosis: A Population-Based Study Using Health Administrative Data., Rebecca Rodrigues, Arlene G Macdougall, Guangyong Zou, Michael Lebenbaum, Paul Kurdyak, Lihua Li, Salimah Z Shariff, Kelly K Anderson

Epidemiology and Biostatistics Publications

OBJECTIVE: Early psychosis is an important window for establishing long-term trajectories. Involuntary hospitalization during this period may impact subsequent service engagement in people with newly diagnosed psychotic disorder. However, population-based studies of involuntary hospitalization in early psychosis are lacking. We sought to estimate the proportion of people aged 16 to 35 years with early psychosis in Ontario who are hospitalized involuntarily at first admission, and to identify the associated risk factors and outcomes.

METHODS: Using linked population-based health administrative data, we identified incident cases of non-affective psychosis over a five-year period (2009-2013) and followed cases for two years to ascertain …

The Impact Of The Diabetes Management Incentive On Diabetes-Related Services, Hospitalizations, And Mortality Risk In Ontario, Thaksha Thavam

Electronic Thesis and Dissertation Repository

Effective diabetes management provided in primary care has the potential to reduce hospitalizations and mortality. To improve diabetes management, a Diabetes Management Incentive (DMI) was introduced by the Ontario government for family physicians practicing in patient enrolment models. This thesis has three main objectives: 1) review the literature on the association between financial incentives for diabetes care and diabetes-related hospitalizations and mortality; 2) and 3) examine the impact of DMI on: diabetes-related services, diabetes-related hospitalizations, diabetes-related hospitalization costs, and mortality risk in Ontario. A review of the literature on the incentives revealed inconsistent findings. The impact of DMI was assessed …

Incorporating Temperature And Precipitation Extremes Into Process-Based Models Of African Lepidoptera Changes The Predicted Distribution Under Climate Change, Madeleine G. Barton, John S. Terblanche, Brent J. Sinclair

Biology Publications

Terrestrial insects are responding to ongoing climate change. While these responses have been primarily linked to rising temperatures, insects are sensitive to desiccation, and the impacts of altered precipitation regimes remain relatively unexplored. Here, we develop a mechanistic model of survival and performance responses to both temperature and desiccation stress, focussing on Lepidoptera in Africa, where a general understanding of such responses to climate change is urgently required. We run the model with climate data from general circulation models at daily time intervals under current (2011–2015) and projected future (2046–2050) climate scenarios. We first simulate four hypothetical, but typical, Lepidoptera …

Stable Isotopic Characterization Of A Coastal Floodplain Forest Community: A Case Study For Isotopic Reconstruction Of Mesozoic Vertebrate Assemblages, Thomas M. Cullen, Fred Longstaffe, Ulrich G. Wortmann, Mark B. Goodwin, Li Huang, David C. Evans

Earth Sciences Publications

Stable isotopes are powerful tools for elucidating ecological trends in extant vertebrate communities, though their application to Mesozoic ecosystems is complicated by a lack of extant isotope data from comparable environments/ecosystems (e.g. coastal floodplain forest environments, lacking significant C₄ plant components). We sampled 20 taxa across a broad phylogenetic, body size, and physiological scope from the Atchafalaya River Basin of Louisiana as an environmental analogue to the Late Cretaceous coastal floodplains of North America. Samples were analysed for stable carbon, oxygen and nitrogen isotope compositions from bioapatite and keratin tissues to test the degree of ecological resolution that can …

Effects Of Water Temperature, Rearing Temperature And Population On Swimming Performance And Temperature Preference In Atlantic Salmon (Salmo Salar), Nicole Zathey

Electronic Thesis and Dissertation Repository

Understanding how animals respond to environmental temperatures is important for the survival and reintroduction of species. My objectives were to determine how swim performance responds across water temperatures, and how rearing temperature or population would affect this performance and temperature preference. Juvenile Atlantic salmon (Salmo salar) from two populations that are currently used for stocking in Lake Ontario (LaHave, Sebago) were reared at two temperatures (11°C, 19°C). I measured critical swim speed and burst swim speed across eight water temperatures (11 – 25°C). Water temperature had no effect on burst speed, while critical swim speed increased with increased …

Statistical Modeling Of Co2 Flux Data, Fang He

Electronic Thesis and Dissertation Repository

Carbon dioxide (CO2) flux is important for agriculture and carbon cycle studies. Only a small proportion of the land is currently covered by proper equipment to directly collect CO2 flux data. The CO2 flux data has an obvious annual cycle with the phase changing from year to year. How to build a model to estimate the annual effect and seasonal dynamics is a challenging task. With the help of the Moderate Resolution Imaging Spectroradiometer (MODIS) which is carried by NASA satellites, corresponding data, such as normalized difference vegetation index (NDVI), is freely available from NASA. Our goals are modeling the …

Canadian Urological Association Guideline On The Care Of The Normal Foreskin And Neonatal Circumcision In Canadian Infants (Full Version), Sumit Dave, Kourosh Afshar, Luis H. Braga, Peter Anderson

Paediatrics Publications

No abstract provided.