Tracking random walks.

In empirical studies, trajectories of animals or individuals are sampled in space and time. Yet, it is unclear how sampling procedures bias the recorded data. Here, we consider the important case of movements that consist of alternating rests and moves of random durations and study how the estimate of their statistical properties is affected by the way we measure them.

Correction: Synaptic Metaplasticity Underlies Tetanic Potentiation in Lymnaea: A Novel Paradigm.

[This corrects the article DOI: 10.1371/journal.pone.

Synaptic metaplasticity underlies tetanic potentiation in Lymnaea: a novel paradigm.

We present a mathematical model that explains and interprets a novel form of short-term potentiation, which was found to be use-, but not time-dependent, in experiments done on Lymnaea neurons. The high degree of potentiation is explained using a model of synaptic metaplasticity, while the use-dependence (which is critically reliant on the presence of kinase in the experiment) is explained using a model of a stochastic and bistable biological switch.

Fluctuation effects in metapopulation models: percolation and pandemic threshold.

Metapopulation models provide the theoretical framework for describing disease spread between different populations connected by a network. In particular, these models are at the basis of most simulations of pandemic spread. They are usually studied at the mean-field level by neglecting fluctuations.