James P. Williams

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In HIV-1 infection, a population of latently infected cells facilitates viral persistence despite antiretroviral therapy (ART). With the aim of identifying individuals in whom ART might induce a period of viraemic control on stopping therapy, we hypothesised that quantification of the pool of latently infected cells in primary HIV-1 infection (PHI) would(More)
We present a novel feature-based non-rigid image registration algorithm using a small number of automatically extracted points and their associated local salient region features. Our automatic registration is a hybrid approach co-optimizing point-based and image-based terms. Motivated by the paradigm of the TPS-RPM algorithm [6], we develop the RHDM (Robust(More)
Droplet Digital PCR (ddPCR) represents a new and alternative platform to conventional quantitative-PCR (qPCR) for the quantitation of DNA templates. However, the proposed improvement in sensitivity and reproducibility offered by ddPCR is not yet fully proven, partly because the delineation between positive and negative responses is not always clear. Data(More)
Methods for the analysis of images of the same scene taken under three different lighting conditions are illustrated. A technique that separates the effects of geometry and surface coloration/texture in this " tri-luminal " environment is developed and experimental results are shown. Exploiting this technique to isolate geometric information, two methods(More)
We examine the use of three techniques, graph cuts, isoperi-metric minimization and random-walk partitioning for the interactive seg-mentation of cardiovascular medical images. These methods can often be used effectively without heavy reliance on learned or explicitly encoded priors. We illustrate, through the use of a toy problem, the basic difference in(More)
This paper shows how to construct a rational Bezier model of a swept surface that interpolates N frames (i.e., N position/orientation pairs) of a fixed rational space curve c(s) and maintains the shape of the curve at all intermediate points of the sweep. Thus, the surface models an exact sweep of the curve, consistent with the given data. The primary(More)
Treatment of HIV-1 infection with antiretroviral therapy (ART) in the weeks following transmission may induce a state of 'post-treatment control' (PTC) in some patients, in whom viraemia remains undetectable when ART is stopped. Explaining PTC could help our understanding of the processes that maintain viral persistence. Here we show that immunological(More)