The concept of a Dirichlet tessellation has been extended to that of a 'finite body' tessellation to provide a more meaningful description of the spatial distribution of non-spherical secondary phase bodies on two-dimensional sections. A finite body tessellation consists of a network of cells constructed from the interfaces of each individual secondary phase body such that every point within a cell is closer to the corresponding body than to any other. Spatial distribution related cell characteristics derived from Dirichlet tessellations have been extended to finite body tessellations. Quantitative comparisons between the two methods indicate that finite body tessellation measurements are more physically representative as well as more sensitive to local distribution characteristics of secondary phases. To reflect the potential application of finite body tessellations, a methodology is described for analysing the effects of particle distribution and morphology on short crack behaviour in particulate reinforced metal matrix composites.

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The physiological alterations as well as the growth were evaluated in seedlings of two liana species, Cuspidaria sceptrum and Fridericia florida, which were transferred from shade to full sunlight conditions. We cultivated one group of seedlings under full sunlight, the second group under natural shade beneath canopy, and the third group was transferred from shade to full sunlight. Reductions on the potential quantum yield of PSII (Fv/Fm) during predawn was detected under full sunlight, but these responses were more pronounced when the plants were transferred from shade to full sunlight. C. cuspidaria lost all leaves developed under shade a few days after transfer. However, at 60 d after transfer, new leaves were already developed and their Fv/Fm values were similar to full sunlight plants. F. florida was able to maintain its leaves after transfer and exhibited gradual recovery of Fv/Fm over time. The initial photoinhibition influenced growth responses of these liana species, in spite of their heliophyte character as adult plants.

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