The article explains why it is necessary to deal with a mechanical stress in thin film coatings especially in multilayer systems. The published model’s properties are overviewed and a new alternative model of mechanical stress in multilayer is proposed. Both models are compared including the discussion of their advantages for utilization in different situations. and V článku jsou uvedeny důvody, proč je významné se zabývat mechanickým napětím tenkých vrstev, zejména systémem více vrstev. Shrnuje vlastnosti modelu uvedeného v literatuře a podává odvození alternativního popisu jednotlivých vrstev. Jsou porovnány oba přístupy a uvedeny výhody jejich použití v různých případech.
The eggs of most dactylogyrid and diplectanid monogeneans that infect Acanthopagrus australis are tetrahedral. The adults of larger species deposit more eggs per worm on average in 24h in vitro: Lamellodiscus major (31.7 eggs) = Allomurray-trema rohustum (31.6 eggs) > Haliotrema spariensis (9.6 eggs) > Lamellodiscus squamosus (3.2 eggs). The eggs of L. squamosus (55.9 pm) and H. spariensis (56.4 pm) are smaller than those of L. major (66.1 pm) and A. robustum (63 pm). These eggs are normally shed into the water column. On the other hand, the eggs of Lamellodiscus acanthopagri are a modified T-shape (97.6 pm) and are attached to the gills by a sclerotised, thom-like filament. 1’he parasite can auto-infect the host, but has a low fecundity (0.05 eggs), possibly to prevent lethal parasite burdens.