Maternal care within the treehopper subfamily Centrotinae has been considered a rare trait. We present observations on maternal care and nymphal behaviour made in 16 rain forest plots in Peninsular Malaysia and Sabah, Borneo, from 1996 to 1998. Females of 11 Centrotinae morphospecies from the tribes Centrocharesini (Centrochares Stål), Gargarini (Ebhul Distant), and Hypsaucheniini (Gigantorhabdus Schmidt, Hybandoides Distant, Pyrgauchenia Breddin, Pyrgonota Stål) produced egg clutches and guarded them. Maternal care was restricted to egg-guarding in all species. Pyrgonota ?bulbosa Buckton eggs hatched successively over a couple of days and females deserted their clutches when most, but not all, 1st instar nymphs had hatched. Nymphs of egg-guarding species lived gregariously and/or by subaggregating, as did some non-guarding species. Leptobelus dama Germar, Gargara semibrunnea Funkhouser, and two Tricentrus Stål spp. were solitary as nymphs and adults.
Extracts of Helleborus roots were traditionally used in the Balkan area for their analgesic action. We report that the pure natural product MCS-18 isolated from this source is a potent, specific and reversible antagonist of the capsaicin receptor, TRPV1, expressed in rat dorsal root ganglion (DRG) neurons. TRPV1 is a nonselective cation channel expressed in a subset of cutaneous and visceral sensory nerve endings and activated by noxious heat, acidity and fatty acid metabolites of arachidonic acid, with a decisive role in inflammatory heat hyperalgesia. MCS-18 inhibited the increase in intracellular calcium concentration evoked in DRG neurons by capsaicin (300 nM) and low pH (5.5) but not by heat (43 ºC). The substance had no effect on the responses mediated by acid-sensing ion channels (ASICs) or the irritant receptor TRPA1. Whole-cell patch-clamp was used to confirm the inhibition of capsaicin-induced currents by MCS-18 which was dose-dependent. The mechanism of inhibition does not require an intact cell, as capsaicin-induced currents were also inhibited in the excised outside-out configuration. The antagonism of the capsaicin and proton action on native TRPV1 by MCS-18 may be of interest for pain therapy., C. Neacsu ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Fossil continental molluscs have not hitherto been regarded as reliable paleoenvironmental indicators. Little was known about their ecological requirements or their position in characteristic biomes of the Quaternary climatic cycle, for instance in the loess steppe. Only recent analyses of their assemblages in a broad environmental context have shown that they are indicative of a number of important environmental phenomena in the same way as pollen grains or vertebrate remains. and Vojen Ložek.
Fossil molluscan successions from ca 450 sites provide evidence of the paleo-environmental history of the Czech Republic and Slovakia during the Quaternary. They not only reflect the Quaternary cycle of warm and cold phases but also a number of various events, such as the impact of the cold oscillation at 8,2 ky BP or the detailed reconstruction in time and space of the habitat patchwork in areas where other fossils are sparse or absent, particularly in karstlands, in the full scale of elevations. and Vojen Ložek.
Wormlion larvae are found in substrates consisting of fine sand or powder, implying that they may be able to distinguish between different substrates according to particle size. To estimate the effects of particle size on wormlions, the pit-building decision of the larvae of the wormlion Vermileo vermileo was observed in four substrates consisting of different sand fractions. Wormlion larvae prefer the finest sand fraction with particle size <= 230 µm. When wormlions (Vermileo vermileo) and antlions (Euroleon nostras) are placed in the same container with two different substrates, interspecific predation does not occur. In two-substrate choice tests larvae of the two species show opposite preferences for two substrates offered. While wormlion larvae readily build pits in the finest sand fraction (<= 230 µm), antlion larvae prefer coarser sand (with particle size 230-540 µm). Wormlion preference for the finest sands and powders, and antlion preference for sands of medium particle size was confirmed by field observations. Sand particle size affects the spatial distribution of sand-dwelling insect larvae and thus may reduce conflicts between heterospecifics.
The lateral saturated hydraulic conductivity, Ks,l, is the soil property that mostly governs subsurface flow in
hillslopes. Determinations of Ks,l at the hillslope scale are expected to yield valuable information for interpreting and
modeling hydrological processes since soil heterogeneities are functionally averaged in this case. However, these data
are rare since the experiments are quite difficult and costly. In this investigation, that was carried out in Sardinia (Italy),
large-scale determinations of Ks,l were done in two adjacent hillslopes covered by a Mediterranean maquis and grass, respectively,
with the following objectives: i) to evaluate the effect of land use change on Ks,l, and ii) to compare estimates
of Ks,l obtained under natural and artificial rainfall conditions. Higher Ks,l values were obtained under the maquis than in
the grassed soil since the soil macropore network was better connected in the maquis soil. The lateral conductivity increased
sharply close to the soil surface. The sharp increase of Ks,l started at a larger depth for the maquis soil than the
grassed one. The Ks,l values estimated during artificial rainfall experiments agreed with those obtained during the natural
rainfall periods. For the grassed site, it was possible to detect a stabilization of Ks,l in the upper soil layer, suggesting that
flow transport capacity of the soil pore system did not increase indefinitely. This study highlighted the importance of the
experimental determination of Ks,l at the hillslope scale for subsurface modeling, and also as a benchmark for developing
appropriate sampling methodologies based on near-point estimation of Ks,l.
Suburbanization - threat or solution. Suburbanization, which is the dominant form of metropolitan growth in postsocialist cities, offers wider variety of housing options, yet at the same time it is a major threat to sustainable developments. The spatially scattered and fragmented pattern of development calls for the implementation of urban growth management policies and instruments.
Text prináša prehľad aktuálnych a nových poznatkov súvisiacich s problematikou zvládania stresu. Približuje najnovšie prístupy k definovaniu konceptu zvládania stresu, ktoré zdôrazňujú úlohu regulácie a emócií v procese zvládania. Zaoberá sa tiež aktuálnymi usmerneniami kategorizácie a sumarizácie najviac rozšírených a používaných dimenzií zvládacích stratégií. V závere popisuje a predstavuje tri najaktuálnejšie trendy v prístupe a výskume zvládania stresu, ktoré sa postupne objavujú aj v slovenských výskumoch., The article provides an overview of actual and new knowledge related to the issue of coping. The text brings the latest definition of coping, which highlights the role of regulation and emotions in the coping process. The author deals with current guidelines to categorize and summarize the most widely used coping strategies. In conclusion the author describes three trends in coping research., Monika Vavricová., and Obsahuje seznam literatury