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

Epidemiology and Biostatistics Publications

No abstract provided.

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.

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 …

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 …

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 …

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 …

Solving The Woolly Mammoth Conundrum: Amino Acid 15n-Enrichment Suggests A Distinct Forage Or Habitat, Rachel Schwartz-Narbonne, Fred J. Longstaffe, Jessica Z. Metcalfe, Grant Zazula

Earth Sciences Publications

Understanding woolly mammoth ecology is key to understanding Pleistocene community dynamics and evaluating the roles of human hunting and climate change in late Quaternary megafaunal extinctions. Previous isotopic studies of mammoths’ diet and physiology have been hampered by the ‘mammoth conundrum’: woolly mammoths have anomalously high collagen δ¹⁵N values, which are more similar to coeval carnivores than herbivores, and which could imply a distinct diet and (or) habitat, or a physiological adaptation. We analyzed individual amino acids from collagen of adult woolly mammoths and coeval species, and discovered greater  ¹⁵N enrichment in source amino acids of woolly …

Joint Outcome Modeling Using Shared Frailties With Application To Temporal Streamflow Data, Lihua Li

Electronic Thesis and Dissertation Repository

Recently there has been tremendous interest in the development of tools for joint analysis of longitudinal data and time-to-event data. This has gained emphasis particularly in clinical studies, where longitudinal measurements on a response may be recorded along with a time-to-event outcome. Joint analysis of multiple outcomes beyond longitudinal and survival have also been considered, for example, joint analysis of a variety of generalized linear models including continuous and count data, or continuous and binomial data. With joint analysis of multiple outcomes, the interest may be analysis of one outcome conditional on the others, or, more typically, analysis of all …