Abandoned military training ranges are important biodiversity refuges in the modern landscape. We surveyed 41 such areas across the Czech Republic in order to establish butterfly diversity and abundances. We found exceptionally high species richness, including many nationally-threatened rarities like Phengaris arion, Polyommatus dorylas and Zygaena punctum. We conclude that the high conservational value of these areas was maintained by the former army activities, which encouraged high habitat heterogeneity. and Pavel Vrba a kol.
Rozsáhlý materiál bráněnek (Stratiomyidae, Diptera) byl studován z různých částí orientální oblasti včetně chráněných území (národních parků a rezervací). V letech 1994–2012 bylo popsáno více než 60 nových druhů a mnoho dalších druhů revidováno na základě typových jedinců uložených v různých světových sbírkách. Probíhal také sběr larev bráněnek a jejich odchov v laboratorních podmínkách. Jejich ústní ústrojí a povrchové struktury byly studovány s ohledem na jejich potravní specializaci., Extensive material of soldier flies (Stratiomyidae) was examined from different parts of the Oriental region including protected areas (Nature Parks and Reserves). During the 1994–2013 period more than 60 oriental species were described and many further species were revised on the basis of type specimens deposited in various world collections. In addition to the study of adults, mainly phytosaprophagous larvae were collected and reared under laboratory conditions. Their mouthparts and surface structures were examined with regard to their food preference., and Rudolf Rozkošný.
Tropical rainforest can be divided into several altitude levels, which vary in light conditions and also in the nature of their flora and fauna. In terms of the occurrence of typical groups of butterflies, we can define these levels by their height range and typical butterfly groups that form mimetic (unilateral and reciprocal) protective complexes there, even though numerous other species also live there which do not belong to these complexes. This issue is described based on the example of lowland tropical forests in South and Central America. and George O. Krizek.
Rhythmic daily changes in the Na,K-ATPase activity have been previously described for rat kidney cortex, showing two peaks: at 0900 h and 2100 h, and two valleys: at 1500 h and 0100 h - 0300 h. The oscillations in Na,K-ATPase activity are produced by an inhibitor, which binds the enzyme and is present in the rat blood plasma at valley times and absent or at very low concentrations at peak times. Since it has been demonstrated that active Na+ extrusion from the cells of several tissues depends not only on the Na,K-ATPase but also on the ouabain-insensitive Na-ATPase, we studied the activity of this latter enzyme of several rat tissues, i.e., kidney cortex, small intestine, liver, heart and red blood cells along the day. None of these tissues showed any variation of their Na-ATPase activity along the day. Preincubation of kidney cortex homogenates obtained at 0900 h, with blood plasma drawn at 0900 h and 1500 h, did not modify the Na-ATPase activity. Our results indicate that the Na-ATPase activity does not oscillate along the day. These results are in agreement with the idea that the Na-ATPase could partially compensate the Na+ transport affected by oscillations of the Na,K-ATPase activity., A. Reyes ... [et al.]., and Obsahuje seznam literatury
Calmodulin (CaM) is a highly conserved calcium sensor protein associated with chilling tolerance in living organisms. It has four EF-hand domains for binding of four Ca2+, two of them located in the N-terminus, and the other two in the C-terminus. A notothenioid CaM gene fragment (CaMm), which only codes for N-terminus of CaM (with two EF-hand domains), was introduced into Nicotiana benthamiana. Effects of its overexpression on chilling tolerance in plants were explored. During 4◦C or 0◦C chilling treatment, both CaMm and CaM transgenic plants showed higher PSII maximum quantum yield, actual quantum yield, and soluble protein content, lower electrolyte leakage and malondialdehyde content than that of the control. The changes in these physiological indices were comparable between the CaMm and CaM transgenic plants during the treatments. These results indicate that the N-terminus of calmodulin is likely the key functional domain involved in the adaptive response to cold stress., T. J. Zhang, L. J. Pan, Q. Huang, L. H. Zhu, N. Yang, C. L. Peng, L. B. Chen., and Obsahuje seznam literatury
Drought impacts severely crop photosynthesis and productivity. Development of transgenic rice overexpressing maize phosphoenolpyruvate carboxylase (PEPC) is a promising strategy for improving crop production under drought stress. However, the molecular mechanisms of protection from PEPC are not yet clear. The objective of this study was: first, to characterize the response of individual photosynthetic components to drought stress; second, to study the physiological and molecular mechanisms underlying the drought tolerance of transgenic rice (cv. Kitaake) over-expressing maize PEPC. Our results showed that PEPC overexpressing improved the ability of transgenic rice to conserve water and pigments during drying as compared to wild type. Despite the fact that drought induced reactive oxygen species and damaged photosystems (especially, PSI) in both lines, higher intercellular CO2 concentration protected the photosynthetic complexes, peptides, and also ultrastructure of thylakoid membranes against the oxidative damage in transgenic rice. In conclusion, although photosynthetic apparatus suffered an inevitable and asymmetric impairment during drought conditions, PEPC effectively alleviated the oxidative damage on photosystems and enhanced the drought tolerance by increasing intercellular CO2 concentration. Our investigation provided critical clues for exploring the feasibility of using C4 photosynthesis to increase the yield of rice under the aggravated global warming., W. J. Shen, G. X. Chen, J. G. Xu, Y. Jiang, L. Liu, Z. P. Gao, J. Ma, X. Chen, T. H. Chen, and C. F. Lv., and Obsahuje seznam literatury