An example device in accordance with an aspect of the present disclosure includes a first module, a second module, and a third module. The first module is coupled to an element whose status is to be determined, and the first module is to receive an input current that increases over time. The second module is to perform a temporal derivative of a voltage across the element. The third module is to provide an output signal based on a current behavior of the element, according to a change in voltage as a function of a change in current.