Study of poly(dA)-poly(dT) DNA molecule electronic structure, by analysing its density of states (DOS), had been conducted. This research employed Green’s function method as tool to determine electron DOS of the DNA numerically. Electric field that was applied along z-axis is used as perturbation to modify electron hopping constant between sites in the molecule. In order to include electric field in the calculation, Miller-Abraham formula was used. Medium interaction with backbone molecules was considered as well within the calculation in the form of backbone disorder. By increasing electric field, the band in electron DOS spectrum appeared to become narrower and several states experience the decrement of DOS.

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Animal locomotion employs different periodic patterns known as animal gaits. In 1993 Collins and Stewart achieved the characterization in quadrupeds and bipeds by using permutation symmetries groups which impose constrains in the locomotion centre called Central Generator Pattern (CGP) in the animal brain. They modelled the CGP by coupling four non linear oscillators and with the only change in the coupling it is possible to reproduce all the gaits. In this work we propose to use coupled chaotic oscillators synchronized with the Pyragas method not only to characterize the CGP symmetries but also evaluate the time serie behaviour when the foot is in contact with the ground for futures robotic applications.

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