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Nigel J Burroughs

Publications and source records attributed to Nigel J Burroughs.

2 recordsLinked to original sources

Automated Acanthamoeba polyphaga detection and computation of Salmonella typhimurium concentration in spatio-temporal images

Interactions between bacteria and protozoa is an increasing area of interest, however there are a few systems that allow extensive observation of the interactions. We examined a surface system consisting of non nutrient agar with a uniform bacterial lawn that extended over the agar surface, and a spatially localised central population of amoebae. The amoeba fed on bacteria and migrated over the plate. Automated image analysis techniques were used to locate and count amoebae, cysts and bacteria coverage in a series of spatial images. Most algorithms were based on intensity thresholding, or a modification of this idea with probabilistic models. Our strategy was two tiered, we performed an automated analysis for object classification and bacteria counting followed by user intervention/reclassification using custom written Graphical User Interfaces.

q-bio.QM

Close contact fluctuations: the seeding of signalling domains in the immunological synapse

We analyse the size and density of thermally induced regions of close contact in cell:cell contact interfaces within a harmonic potential approximation, estimating these regions to be below one-tenth of a micron across. Our calculations indicate that as the distance between the close contact threshold depth and the mean membrane-membrane separation increases, the density of close contact patches decreases exponentially while there is only a minimal variation in their mean size. The technique developed can be used to calculate the probability of first crossing in reflection symmetry violating systems.

physics.bio-ph