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Physical modeling is increasingly important for generating insights into intracellular processes. We describe situations in which combined spatial and stochastic aspects of chemical reactions are needed to capture the relevant dynamics of biochemical systems.
Widely used behavioral assays need re-evaluation and validation against their intended use. We focus here on measures of chronic anxiety in mouse models and posit that widely used assays such as the open-field test are performed at the wrong time, for inadequate durations and using inappropriate mouse strains. We propose that behavioral assays be screened for usefulness on the basis of their replicability across laboratories.