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Cellular networks may be found in a variety of natural contexts, from soap foams to biological tissues to grain boundaries in a polycrystal, and the characterization of these structures is therefore a subject of interest to a range of disciplines. An approach to describe the topology of a cellular network in two and three dimensions is presented. This allows for the quantification of a variety of features of the cellular network, including a quantification of topological disorder and a robust measure of the statistical similarity or difference of a set of structures. The results of this analysis are presented for numerous simulated systems including the Poisson-Voronoi and the steady-state grain growth structures in two and three dimensions.

Nanoindentation has become ubiquitous for the measurement of mechanical properties at ever-decreasing scales of interest, including some studies that have explored the atomic-level origins of plasticity in perfect crystals. With substantial guidance from atomistic simulations, the onset of plasticity during nanoindentation is now widely believed to be associated with homogeneous dislocation nucleation. However, to date there has been no compelling quantitative experimental support for the atomic-scale mechanisms predicted by atomistic simulations. Our purpose here is to significantly advance the quantitative potential of nanoindentation experiments for the study of dislocation nucleation. This is accomplished through the development and application of high-temperature nanoindentation testing, and the introduction of statistical methods to quantitatively evaluate data. The combined use of these techniques suggests an unexpected picture of incipient plasticity that involves heterogeneous nucleation sites, and which has not been anticipated by atomistic simulations.

The paper considers the status of the wrongful life action particularly in the light of the recent acceptance of such actions in continental Europe. It is considered that the hurdle of causation is still not adequately overcome in these cases and, in a search for an answer to the difficulty, the author re-examines the Canadian case of Cherry v Borsman. This case was originally thought of as one of wrongful life associated with a negligently performed abortion and the paper attempts to overcome the problems of causation by comparing and contrasting the roles of the genetic counsellor and the abortionist. While the attempt is by no means wholly successful, it also serves to draw attention to some significant differences between wrongful life actions based on physical and mental disability in the neonate.