380 research outputs found
Charting the Pandemic with Data Modelling — with Caroline Colijn
No full textSFU Mathematics professor Caroline Colijn joins host Am Johal to talk about the role of data modelling in the response to COVID-19. Caroline holds the Canada 150 Research Chair in Mathematics for Infection, Evolution and Public Health, and works at the intersection of mathematics and public health, with a particular focus on the spread and evolution of infectious diseases.She has been working alongside colleagues since the beginning of the pandemic, using data to mathematically model the trajectory of COVID-19 and to inform public policy. In this interview, she gives a brief overview of how we\u27ve arrived at this point in the pandemic here in BC. They discuss the potential benefits of prioritizing high-contact workers in the rollout of vaccines, variants of concern in BC, and what data tells us about COVID-19 spread in the weeks and months to come
The de Broglie-Bohm Causal Interpretation of Quantum Mechanics and its Application to some Simple Systems
No full textThe de Broglie-Bohm causal interpretation of quantum mechanics is discussed, and applied to the hydrogen atom in several contexts. Prominent critiques of the causal program are noted and responses are given; it is argued that the de Broglie-Bohm theory is of notable interest to physics. Using the causal theory, electron trajectories are found for the conventional Schrodinger, Pauli and Dirac hydrogen eigenstates. In the Schrodinger case, an additional term is used to account for the spin; this term was not present in the original formulation of the theory but is necessary for the theory to be embedded in a relativistic formulation. In the Schrodinger, Pauli and Dirac cases, the eigenstate trajectories are shown to be circular, with electron motion revolving around the z-axis. Electron trajectories are also found for the 1s-2p 0 transition problem under the Schrodinger equation; it is shown that the transition can be characterized by a comparison of the trajectory to the relevant eigenstate trajectories. The structures of the computed trajectories are relevant to the question of the possible evolution of a quantum distribution towards the standard distribution (quantum equilibrium); this process is known as quantum relaxation. The transition problem is generalized to include all possible transitions in hydrogen stimulated by semi-classical radiation, and all of the trajectories found are examined in light of their implications for the evolution of the distribution to the distribution. Several promising avenues for future research are discussed
Modelling and genomic analysis of competition and diversity in Mycobacterium tuberculosis
No full textNumerous studies have identified tuberculosis patients in whom more than one distinct strain of Mycobacterium tuberculosis (M. tuberculosis) is present. The diversity of M. tuberculosis can have dramatic effects on disease dynamics. This thesis focuses on the study of diversity of M. tuberculosis and competition between its strains by analysing mathematical models and applying statistical techniques to clinical, genetic and epidemiological data.
Mathematical models of M. tuberculosis, both in-vitro and within host are developed and analysed. Single strain models are analysed and then extended to incorporate the interaction of two or more M. tuberculosis strains. We find that during active disease, competition between strains is not as severe as during latency. Analysis of the within host models using approaches from data science identify key model parameters that affect the outcome of infection. These models are further explored using virtual experiments to answer questions such as how does re-infection affect disease progression?
Evolutionary tools, especially phylogenetic trees, are increasingly being used to study short-term variation in M. tuberculosis. Some regions of a genome sequence may be disruptive in a phylogenetic framework. We propose a phylogeny-based method to detect phylogenetically disruptive sites along a multiple sequence alignment and illustrate the effect excluding these sites has on onward inference of the phylogeny.
In many Western countries tuberculosis (TB) incidence is low and largely shaped by immigrant populations originating from high-burden countries. We combine whole genome sequence data, times of arrival in Norway and case presentation times to estimate the time of transmission for individual patients. We focus on genomic clusters of patients originally from the horn of Africa. We find that there is strong evidence of ongoing TB transmission in Norway within these populations. These results show how genomic and epidemiological data can be combined to provide useful information for public health.Open Acces
Age-related Macular Degeneration: Genetic Epidemiologic findings from large European studies
No full textCharting a future for emerging infectious disease modelling in Canada
No full textThis paper arose out of a workshop at the Banff International Research Station (BIRS) held from January 19–22, 2023 entitled “Charting a Future for Emerging Infectious Disease Modelling in Canada”, led by Mark Lewis, Patrick Brown, Christopher Cotton, Caroline Colijn, Kumar Murty and Nick Ogden. We thank the new BIRS-Now program for providing the resources and inspiring environment that made it possible to build the shared vision that formed the basis for the paper.We propose an independent institute of emerging infectious disease modellers and policy experts, with an academic core, capable of renewing itself as needed. This institute will combine science and knowledge translation to inform decision-makers at all levels of government and ensure the highest level of preparedness (and readiness) for the next public health emergency. The Public Health Modelling Institute will provide cost-effective, science-based modelling for public policymakers in an easily visualizable, integrated framework, which can respond in an agile manner to changing needs, questions, and data. To be effective, the Institute must link to modelling groups within government, who are best able to pose questions and convey results for use by public policymakers.FacultyUnreviewe
Metrics on phylogenetic tree shapes
No full textNon UBCUnreviewedAuthor affiliation: Imperial College LondonFacult
Influence of strain rate on deformation behaviour, austenite structure and kinetics of the [gamma/alpha] transformation of steels : final report
No full textInfluence of strain rate on deformation behaviour, austenite structure and kinetics of the [gamma/alpha] transformation of steels : final report
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