A normally off nitride-based transistor may include a source electrode and a drain electrode, a channel layer serving as a charge transfer path between the source electrode and the drain electrode, and a gate electrode that controls charge transfer of the channel layer. The collector captures exhaust particles in exhaust gas. A reference vector specifying a plurality of features associated with the reference point-of-interest is retrieved. The storage unit stores a second audio digital signal. The stabilizer composition is particularly suitable for stabilizing thermoplastic polyurethane with respect to light, oxygen, and heat.