Bioimaging Seminar, 26th May 2010
Wednesday 26th May, 10:00 – 12:00
Warwick Mathematics Institute
Zeeman Building, Room B3.02
- Thomas Nichols, Department of Statistics & Warwick Manufacturing Group: "Hierarchical Spatial Bayesian Model for Functional MRI"
- Liming Ying, Imperial College London: "Seeing Is Believing: Single Molecule Fluorescence Approaches to Biology"
More information on the Bioimaging Seminar Series can be found here
Thomas Nichols, Department of Statistics & Warwick Manufacturing Group: "Hierarchical Spatial Bayesian Model for Functional MRI"
Psychologists use Functional Magnetic Resonance Imaging (fMRI) to view the brain 'in action', measuring changes in blood flow that identify which regions are used to, for example, remember words, perceive pain or engage emotions. The statistical methodology of these brain mapping studies, however, depends on mass-univariate linear modelling, a rich suite of tools for fitting and making inference on brain image data. I will review the standard mass-univariate analysis methods and highlight their shortcomings, in particular their inability to explicitly model the spatial structure of the fMRI signals. I will present a hierarchical spatial model for multi-subject fMRI analyses, where latent population- and individual-centres fit the focal signals. The model uses priors for identifiability and full posterior sampling to provide inference on a variety of measures of interest unavailable in a mass-univariate framework, including population prevalence of activation and inter-subject spread of activation about population centres. I show evaluations of the model with simulations and demonstrate it with real data. Time permitting, I will also show how this framework generalizes to other settings, including 'spatial meta-analyses' and and lesion modelling in Multiple Sclerosis.
Liming Yin, Imperial College London: "Seeing Is Believing: Single Molecule Fluorescence Approaches to Biology"
Single molecule methods detect, characterise and manipulate single biomolecules, molecular complexes and molecular machines, and have transformed many areas of life sciences over the last 15 years. In this seminar, I will briefly introduce my own work in this exciting research area, focusing on the applications of single molecule FRET in exploring the conformational heterogeneity and dynamics of intramolecular DNA quadruplexes and full-length p53 as well as distinguishing folding mechanism of small fast folding protein. I will also present our latest work on developing a general method to measure the stoichiometry of individual protein oligomers in living bacterial cells by fluorescence photobleaching.