We have measured the time resolved Stokes shift of the probe molecule quinoxaline in glass-forming solvents of different polarities under the condition of geometrical confinement, for which this solvation dynamics technique is particularly suitable. While solvation probes the local dielectric relaxation in polar liquids, it is associated with the local mechanical responses in non-polar systems. The effect of porous glasses on the relaxations of supercooled liquids is strongly dependent on the surface chemistry and can be rationalized on the basis of the cooperativity concept. We also present evidence for the heterogeneous nature of relaxation dynamics in nano-confined liquids. In a further experiment, in which the chromophores are selectively positioned at the liquid/solid interface, we observe that the relaxation in the immediate vicinity of the glass surface can be qualitatively similar to the bulk behaviour. †

It is shown how optimal Lévy flight searching patterns for the location of sparsely and randomly distributed targets can emerge from conspecific avoidance (i.e. behaviour designed to avoid locations previously traversed by individuals of the same species).

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The effects of inhomogeneities of the drive field H, and of the in-plane anisotropy on the generation of vertical Bloch line pairs in the stripe domain wall were investigated numerically. It was found that the inhomogeneity of H, does not cause the generation of vertical Bloch line pairs in the linear range of wall motion (i.e. H, < HzcriJ. In the case of the inhomogeneity of the in-plane anisotropy, however, the generation of vertical Bloch lines appears also for H, < H,,,,,,provided that such an inhomogeneity is sufficiently large.