Abstract: An autonomous machine arranged to provide an observable measure of the mechanical energy dissipated by the machine relative to that stored by the machine, so that the decision making of the machine's control system can be based on a real energetic stress of the machine. The autonomous machine has a control system with predictive models for the internal and external environments. Both predictive models are based on the same set of information representing a common energetic basis of the machine. The set of information includes: (i) a plurality of reciprocal signals indicative of the machine's direct interactions, and (ii) a plurality of non-reciprocal signals indicative of information that is available to the machine without requiring it to expend energy. The plurality of non-reciprocal signals includes emulated signals where needed to ensure that the predictive models for the internal and external environments are based on an equivalent set of parameters.

Abstract: An antibacterial peptide obtainable from a S. mitis and S. oralis; or a variant thereof, or a fragment of any of these, for use as an antibacterial agent. Specific peptides have been identified. These peptides are secreted by strains of S. mitis or S. oralis. They are active against inter alia gram negative bacteria and Staphylococcal spp. The peptides may be isolated for use or the S. mitis or S. oralis may be used in a probiotic therapy.