Light response of the chlorophyll fluorescence parameters and partitioning of absorbed light energy in wild type and npq4 mutant of Arabidopsis thaliana

Photoprotective thermal dissipation of absorbed light energy is measured as non-photochemical quenching (NPQ) of chlorophyll fluorescence during exposure of plants to higher light intensities. We investigated the light response behavior of chlorophyll fluorescence and energy partitioning in PSII of npq4 mutant of Arabidopsis thaliana, which is lacking of PsbS protein, to that of the wild type plants. We found that the PsbS protein appears to function not only in thermal dissipation in light via xanthophyll pigments, but also modified the allocation pattern of excitation energy absorbed in the PSII to PSII photochemistry (P), thermal dissipation in light (DL) and excess excitation (E)

Notes on Leptocampoplex cremastoides (Hymenoptera, lchneumonidae, Campopleginae), a new genus and species to the Finnish fauna

Leptocampoplex cremastoides (Holmgren, 1858) is reported as new to Finland. The taxonomy and the biology of the species is shortly reviewed

Shape of an elastica under growth restricted by friction

We investigate the quasi-static growth of elastic fibers in the presence of dry or viscous friction. An unusual form of destabilization beyond a critical length is described. In order to characterize this phenomenon, a new definition of stability against infinitesimal perturbations over finite time intervals is proposed and a semi-analytical method for the determination of the critical length is developed. The post-critical behavior of the system is studied by using an appropriate numerical scheme based on variational methods. We find post-critical shapes for uniformly distributed as well as for concentrated growth and demonstrate convergence to a figure-8 shape for large lengths when self-crossing is allowed. Comparison with simple physical experiments yields reasonable accuracy of the theoretical predictions