Irregular cells

It exhibits solutions in the form of spatially-irregular cells" splitting and merging in a chaotic manner in time. An example of spatio-temporal behavior of a chaotic solution of the Kuramoto-Sivashinsky equation (158) as well as a snapshot of this solution at a particular moment of time are shown in Fig.20. 

Fig. 40. Schematic illustration of the network of irregular cells, with walls parallel to 449, partitioning the superconducting plane of 123-06 9- After Etheridge (1996).

Surfactants are used to control cell development. Both cell size and shape are affected to the extent that, without surfactant additives, large irregular cells may develop or the foam may collapse altogether. The most widely used type of surfactant for rigid-closed cell PU foams is based on silicone copolymers, although organic types, such as sulfonated castor oil and amine esters of fatty acids, are also used. 

In some gelatinous lichens, for example in Leptogium, the hyphae are compacted at the surface of the thallus into a pseudoparenchymatous layer which is only one cell thick. Seen from above, this tissue consists either of isodiametric cells pressed together in an unbroken layer or of loosely organized irregular cells (Fig. 22). 

Peripheral neuronal PG12 cells were treated with silver NPs (15nm, 5 rgmT culture media) for 24 h. After treatment, on examination at low magnification the cells appeared shrunken, with irregular cell borders moreover, the cells showed more reductive activity following exposure to silver NPs than to other nanoparticles, such as Mn particles of 40 nm diameter. The addition of silver NPs (50 pg ml" ) also led to a depletion of dopamine and its metaboUtes dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA). In addition, the treatment of PC12 cells... 

Figure 6.24 Irregular cell geometries that may be treated using the finite voliune method.

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