The colon-pile

Alexei Vazquez

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arXiv · 2003.03232

The colon-pile

Alexei Vazquez

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Abstract

Bacteria populate the colon where they replicate and migrate in response to nutrient availability. Here I model the colon bacterial population as a sandpile model, the colon-pile. Sand addition mimics bacterial replication and grains toppling represents bacterial migration coupled to high population density. The numerical simulations reveal a behaviour similar to non-conservative sandpile models, approaching a critical state with system wide avalanches when the death rate becomes negligible. The critical exponents estimation indicates that the colon-pile belongs to a new universality class. This work suggest that the colon microbiome is in a self-organised critical state, where small perturbations can trigger large scale rearrangements, covering an area comparable to the system size and characterised by a 1/f noise spectra

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Alexei Vazquez. 2020-03-06. The colon-pile. https://arxiv.org/abs/2003.03232

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