Srážky s velkými savci způsobují škody na vozidle a často i zranění posádky. V rámci České republiky jsme s využitím statistického modelu identifikovali místa, kde opakovaně k těmto kolizím dochází. Hlavním cílem studie však bylo vyhodnotit mortalitu drobných obratlovců na těchto úsecích, která není nikde evidována. Zjistili jsme, že úmrtnost drobných obratlovců souvisí především s typem biotopu. Nejvíce kadaverů bylo nalezeno na rozhraní lesa a pole, přestože zde byla ze sledovaných úseků nejnižší intenzita dopravy., Collisions with large mammals cause damage to the vehicles and frequent injuries to the occupants. By using a statistical model we identified clusters of traffic accidents with animals on the Czech road network. However, the main aim of our study was field monitoring of the mortality of small vertebrates, which are usually not mentioned in police databases. The major parameter that influences the mortality of small vertebrates was the type of habitat in the surrounding area. Most carcasses were found in the ecotone (field – forest), despite the lowest traffic intensity recorded there., and Tomáš Bartonička ... [et al.].
Steroid hormone 20-hydroxyecdysone and the sesquiterpenoid juvenile hormone are the main regulators of insect development; however, it is unclear how they interact in the regulation of metamorphic events. Using the silkworm, Bombyx mori, we show that the juvenile hormone analogue fenoxycarb affects the cascade of ecdysone regulated genes that control the programmed cell death in the larval midgut. Morphological changes that occur during cell death were investigated by studying cross-sections of the midgut stained with hematoxylin and eosin. Apoptosis-specific DNA fragmentation was detected using TUNEL assay. Expression patterns of genes ATG8 and ATG12, which were used as indicators of autophagy, and genes of the ecdysone-regulated gene cascade were examined using real-time quantitative polymerase chain reaction. Fenoxycarb application on day 0 of the 5th larval instar extended the feeding period and postponed programmed cell death in mature larval midgut. This effect was probably due to a delay in ecdysone secretion and associated changes in gene expression were mostly not a direct response to the fenoxycarb. However, differences in the gene expression patterns in the control and fenoxycarb treated insects during the prepupal and early pupal stages indicated that fenoxycarb may also exert a more direct effect on some genes of the ecdysone regulated gene cascade., Ebru Goncu, Ramazan Uranli, Osman Parlak., and Obsahuje bibliografii
In the epiphytic tillandsioids, Guzmania monostachia, Werauhia sanguinolenta, and Guzmania lingulata (Bromeliaceae), juvenile plants exhibit an atmospheric habit, whereas in adult plants the leaf bases overlap and form water-holding tanks. CO2 gas-exchange measurements of the whole, intact plants and δ13C values of mature leaves demonstrated that C3 photosynthesis was the principal pathway of CO2 assimilation in juveniles and adults of all three species. Nonetheless, irrespective of plant size, all three species were able to display features of facultative CAM when exposed to drought stress. The capacity for CAM was the greatest in G. monostachia, allowing drought-stressed juvenile and adult plants to exhibit net CO2 uptake at night. CAM expression was markedly lower in W. sanguinolenta, and minimal in G. lingulata. In both species, low-level CAM merely sufficed to reduce nocturnal respiratory net loss of CO2. δ13C values were generally less negative in juveniles than in adult plants, probably indicating increased diffusional limitation of CO2 uptake in juveniles., J. D. Beltrán ... [et al. ]., and Obsahuje bibliografii