Body size is one of the most investigated traits in studies of sexual selection in fruit flies of the genus Drosophila. In D. melanogaster, size has often been correlated with male mating success, i.e. larger males were more successful in achieving copulations both in laboratory and field conditions. In the present paper, we investigated if male body size is a sexually selected trait in competitive conditions, when full-sibs that developed at two different temperatures (18 and 25°C) competed for females. Males developed at a lower temperature were significantly larger than those reared at a higher temperature, but they were not more successful in mating. We conclude that when body size is significantly induced by temperature variability, it is not correlated with male mating success., Sofija Pavkovic-Lučic, Vladimir Kekic., and Obsahuje seznam literatury
F.xcept other functions, surface saccharide residues on trematode larvae are supposed either to be the targets of the intermediate (molluscan) and final host immune systems, or to represent candidates for molecular mimicry. Therefore, changes in surface saccharide patterns during the development of the avian schistosome Trichobilharzia szidati were characterized. Whole parasite larval stages and their tissue sections were examined using FITC-conjugated lectins. Marked surface differences were found among larval stages (miracidia, mother sporocysts, daughter sporocysts, cercariae, schistosomula). Staining by some lectins reflected known ultrastructural changes of the outer tegument. Reaction of lectins with cercarial embryos was almost negative. In case of other developmental stages, binding of at least one member from each carbohydrate-specificity group of lectins (Man/Glc-, GIcNAc-, Gal/GalNAc- and Fuc-specific) occurred. One exception is represented by mother and daughter sporocysts which practically failed to react with Fuc-specific lectins. Besides other lectins which recognized larval surfaces, a-L-fucose-specific lectins (LTA, UEA-I) and (GlcNAcfll —>4)„-spccific WGA bound very strong to certain stages. The comparison of mature intrasporocystic cercariae with those emerged from snails brought the indication that some snail glycosylated molecules adhere to the surface of schistosome larvae or that emerged cercariae express some new carbohydrate epitopes under changed environmental conditions. The result partially supports the theory of parasite mimicry/masking strategies and immune evasion in the host.
Rozložená titulní stránka., Obálkový název: Devětsil : the Czech avant-garde art architecture and design of the 1920s and 30s, and Obálkový název: Devětsil : Czech avant-garde art, architecture and design of the 1920s and 30s
Neurotrophins are present in the gastrointestinal tract where they participate in the survival and growth of enteric neurons, augmentation of enteric circuits, elevation of colonic myoelectrical activity and also in different aspects of colitis. Previous studies largely focused on the role of neural and mucosal neurotrophins in gut inflammation. The expression of neurotrophins in colonic smooth muscle cells (SMCs) and the interactions of this potential source with colitis has not been studied in the gut. The expression of NGF, BDNF, NT-3 and NT-4 in SMCs from longitudinal and circular muscle layers of rat colon from normal and dextran sodium sulphate (DSS)-induced colitis rats was measured by ELISA. NGF, BDNF, NT-3 and NT-4 are
differentially expressed in both longitudinal and circular SMCs, where the expressions of BDNF and NT-4 proteins were greater in SMCs from the longitudinal muscle layer than from the circular muscle layer, while NGF protein expression was greater in circular SMCs and NT-3 expression was equal in cells from both muscle layers. Induction of colitis with DSS significantly alters neurotrophins expression pattern in colonic SMCs. NGF levels upregulated in circular SMCs. BDNF level was increased in DSS-induced colitis in longitudinal SMCs. NGF, NT-3 and NT-4 levels were downregulated in longitudinal SMCs of DSS-induced colitis rats' colon. Disturbances of neurotrophins
expression in SMCs resulted from colitis might account for the structural and functional changes in inflammatory bowel disease (IBD) such as loss of innervation and characteristic hypercontractility of longitudinal muscle in IBD.
The theory of elasticity is a very important discipline which has a lot of applications in science and engineering. In this paper we are interested in elastic materials with different properties between interfaces implicated the discontinuous coefficients in the governing elasticity equations. The main aim is to develop a practical numerical scheme for modeling the behaviour of a simplified piecewise homogeneous medium subjected to an external action in 2D domains. Therefore, the discontinuous Galerkin method is used for the simulation of elastic waves in such elastic materials. The special attention is also paid to treatment of boundary and interface conditions. For the treatment of the time dependency the implicit Euler method is employed. Moreover, the limiting procedure is incorporated in the resulting numerical scheme in order to overcome nonphysical spurious overshoots and undershoots in the vicinity of discontinuities in discrete solutions. Finally, we present computational results for two-component material, representing a planar elastic body subjected to a mechanical hit or mechanical loading.