One of the best documented effects of climate change on biodiversity are shifts in phenology. However, long-term data quantifying and projecting the expected changes in phenology associated with climate warming are limited to a few well-recorded areas in the world. In the absence of temporal recording, an alternative approach is to determine the phenological response of species along marked gradients in climate or along latitudinal or altitudinal transects (space-for-time substitution). We studied the phenology (timing and duration of the flight period) of butterflies in 2006 along an altitudinal gradient (900-1680 m; estimated temperature lapse rate = -6.6°C/km) in the Serranía de Cuenca (central Spain) at the assemblage and individual species levels. Timing of the flight period was later for assemblages at high than at low altitudes. A similar trend of an increasing delay in the flight period with altitude was recorded for some individual species. However, there were also some exceptions to this pattern regardless of the number of sites and the altitudinal ranges of the species, suggesting possible local adaptation to regional climate. The duration of the flight period was shorter at high altitudes for assemblages, but this trend was not mirrored in the response of individual species. The results partly support substituting space-for-time when assessing the potential effect of climate change on phenophases such as the timing of the flight period, but we recommend extreme caution in extrapolating the results in the absence of information on how the responses of populations differ. and Juan Ignacio De Arce Crespo, David Gutiérrez.
On the basis of solid-state aluminium-27 nuclear magnetic resonance measurements a new organo-aluminium complex in coal substance was discovered in the solid extracts obtained both from the Ostrava-Karviná bituminous coal and the North Bohemian Basin brown coal. In the 27 Al MAS NMR spectra it was found that the significant chemical shift at 13.6-14.6 ppm corresponds with that obtained for the aluminium hexaphenoxide complex (14.2 ppm). Therefore, organo-aluminium complex with hexa-coordination to oxygen is present in coal substance., Pavel Straka., and Obsahuje bibliografické odkazy
The Association for Youth, Science and Technology is a non-governmental, non-profit organization of children and youth. AMAVET brings together 3500 registered active members working in various scientific disciplines. AMAVET plays an important role in conjuction with schools and school institutions, in forming the mindset of young people through informal education, which is becoming a valuable part of a whole life education. The Committee of AMAVET has chosen the ten best student projects on May 6-7, 2008 at the Academy of Sciences of the Czech Republic. and Gabriela Adámková.
V ČR a Polsku se v posledním období významným zahraničněpolitickým i vnitropolitickým tématem stal záměr vlády USA umístit v těchto zemích některé komponenty budovaného amerického systému obrany proti mezikontinentálním balistickým střelám, který by podle deklarovaného záměru měl chránit kontinentální území Spojených států před případným útokem prostřednictvím menšího počtu raket dlouhého doletu z tzv. „ničemných států“ (rogue states), jak je označuje americká administrativa. Vlády ČR a Polska byly v tomto směru nedávno oficiálně americkou stranou požádány diplomatickou nótou o jednání v této záležitosti. V případě Polska by se mělo jednat o odpalovací zařízení raket určených k ničení mezikontinentálních balistických střel, na českém území by pak měl být dislokován radar, jehož prostřednictvím protiraketový systém vyhledává nepřátelské střely a navádí na ně své rakety. Probíhající diskuse jak uvnitř obou oslovených středoevropských států, tak i na mezinárodním foru zřetelně ukazují, že jak konkrétní plán umístit základny antibalistické obrany v ČR a Polsku, tak zejména samotný záměr budovat byť i jen omezený systém strategické obrany tohoto druhu, představuje závažnou, značně citlivou a kontroverzní otázku s globálním dosahem. Pochopitelný a průběžně sílící zájem o věc projevují také obyvatelé obou zemí. A právě postojům české a polské veřejnosti k celému projektu, jejich aktuálnímu stavu a také možnému dalšímu vývoji se bude věnovat tento text., The text focuses on public opinion in Czech Republic and Poland relating to the plan of U.S. government to locate some parts of U.S. national missile defence in these countries. It describes and compares main shifts of developments of public attitudes in both countries to the project as well as to eventual referendum in this matter within the period up to the first half of 2007. The text shows main demographical, societal and political differences in both countries and discusses reasons and motives behind particular attitudes of Czech and Polish citizens., Jan Červenka., and Seznam literatury
In laboratory experiments, conspecific excretions and ammonia solutions evoked avoidance reactions in tadpoles of three anuran species, Bufo bufo, Rana temporaria, and Rana arvalis . A differential sensitivity of ammonia chemoreception was determined for two anuran species. For Bufo bufo tadpoles, these characteristics at ammonia backgr ound concentration of 0.2 mg/l lied in the range 150 % < dI/I < 500 %, and for background of 0.4 mg/l the value lied in th e range 400 % < dI/I < 500 %. For Rana temporaria tadpoles, differential threshold against ammonia background concentration of 0. 15 mg/l was close to 200 % and against background ammonia concentration of 1.1 mg/l was close to 100 %. These results suggest that such sensitivity of both anurans is sufficient for using ammonia in intra- and interspecies communication., Y. B. Manteifel, E. I. Kiseleva., and Obsahuje bibliografii a bibliografické odkazy
Metabotropic glutamate receptors (mGluRs) represent a potential therapeutic target. Possible anticonvulsant action of AMN 082, an agonist of mGluR7 subtype, was studied in immature rats using pentylenetetrazol (PTZ)-induced seizures as a model. Five age groups of rats (7-, 12-, 18-, 25-day-old and adult animals) were pretreated with AMN 082 in doses of 0.5, 1, 2, and 5 mg/kg i.p. and 30 min later PTZ was administered (100 mg/kg s.c.). Controls received saline instead of the agonist. AMN 082 did not exhibit clear anticonvulsant action with the exception of suppression of the tonic phase of generalized tonic-clonic seizures (GTCS) in 12-day-old rats. Shorter latencies of GTCS after AMN 082 pretreatment indicate a proconvulsant action. Involuntary movements (mostly tremor) appeared after AMN 082 before PTZ administration, therefore we performed another experimental series with AMN 082 only (1, 2, 5, and 10 mg/kg i.p.). During 60-min observation period tremor appeared in all age groups; sensitivity to this action decreased with age from the 2 mg/kg dose in 7- and 12-day-old rats to the 10 mg/kg dose in adult rats. Mixed anti- and proconvulsant actions of AMN 082 together with unwanted motor effects makes clinical use of this drug highly improbable., Pavel Mareš., and Obsahuje bibliografii a bibliografické odkazy
The object of the research was to investigate the spectral properties of Rayleigh-type surface waves, generated by shot-hole explosions during seismic refraction experiments which were carried out in the area of the Bohemian Massif and West Carpathians. The records of displacement amplitudes were spectrally analyzed and prevailing frequency fp, relative Δfr and absolute widths of the spectra Δfa were chosen as essential parameters. Whilst the prevailing frequencies were recorded within the interval f ÷ 0.80 - 3.70 Hz at the site of the observations, situated on the territory of the Bohemian Massif, the respecti ve frequency range f ÷ 0.80 - 2.6 Hz was found in the West Carpathians. Some functional dependences of the spectral amplitude parameters on epicentral distance were observed and regularities of their decrease were defined. Moreover, the influence of local seismogeological conditions at the shot point as well as at the site of observation occurred., Karel Holub., and Obsahuje bibliografické odkazy