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The nematodeCaenorhabditis elegansis a widely used model organism for neuroscience. Although its nervous system has been fully reconstructed, the physiological bases of single-neuron functioning are still poorly explored. Recently, many efforts have been dedicated to measuring signals fromC.elegansneurons, revealing a rich repertoire of dynamics, including bistable responses, graded responses, and action potentials. Still, biophysical models able to reproduce such a broad range of electrical responses lack. Realistic electrophysiological descriptions started to be developed only recently, merging gene expression data with electrophysiological recordings, but with a large variety of cells yet to be modeled. In this work, we contribute to filling this gap by providing biophysically accurate models of six classes ofC.elegansneurons, the AIY, RIM, and AVA interneurons, and the VA, VB, and VD motor neurons. We test our models by comparing computational and experimental time series and simulate knockout neurons, to identify the biophysical mechanisms at the basis of inter and motor neuron functioning. Our models represent a step forward toward the modeling ofC.elegansneuronal networks and virtual experiments on the nematode nervous system. 

Dual voltage-calcium fluorescence optical recordings are increasingly appealing to characterize complex spa-tiotemporal cardiac dynamics within ex-vivo whole-heart ex-perimental preparations. Synchrony among voltage and calcium signals allows us to unveil novel multi-scale and multi-physics couplings at the ventricular scale and quantify features that define the intrinsic nonlinearities of the observed phenom-ena. Within such a complex scenario, we propose a rigorous methodological analysis comparing and contrasting multiple cardiac alternans onset and evolution indicators for rabbit pacing-down restitution protocols. We introduce a novel integral index quantified upon voltage and calcium signals, validated against well-accepted post-processing analyses, and generalized in terms of statistical restitution curves obtained under four different thermal states. Our study suggests that such a novel indicator can further advance our predictability on alternans onset, linking the concurrent evolution to an innovative quan-tification of the characteristic length obtained for both voltage and calcium at different thermal states.