Diurnal variation of gas exchange, chlorophyll (Chl) fluorescence, and xanthophyll cycle components of three maize (Zea mays L.) hybrids released in different years, i.e. Baimaya (1950s), Zhongdan2 (1970s), and Nongda108 (1990s), were compared. On cloudless days, the newer hybrids always had higher net photosynthetic rate (PN), especially at noon, than the older ones. At noon, all the hybrids decreased their maximal yield of photosystem 2 (PS2) photochemistry (Fv/Fm) and actual quantum yield of PS2 (ΦPS2), the newer ones always showing higher values. Generally, the newer hybrids displayed higher photochemical quenching of Chl (qP) and lower non-photochemical quenching (NPQ). The interhybrid differences in PN may be owing to their differential photochemical efficiency. A midday depression in P N occurred in all hybrids, which might be caused by serious photoinhibition or by decreased stomatal conductance. However, midday depression in PN was more obvious in the older hybrids, especially when leaves were senescent. The higher de-epoxidation state of the xanthophylls was noted in older hybrids, which was confirmed by their larger NPQ. The newer maize hybrids did not need a strong de-epoxidation state since they had a better photosynthetic quantum conversion rate and a lower NPQ. and L. Ding ... [et al.].
Two hundred and seventeen captive great apes (150 chimpanzees, Pan troglodytes; 14 bonobos, Pan paniscus; 53 western gorillas, Gorilla gorilla) and 20 personnel from thirteen European zoos and two African sanctuaries were sampled and examined in order to determine the occurrence of Enterocytozoon bieneusi and species of Encephalitozoon in faecal specimens and to compare the epidemiological situation between zoos and sanctuaries. Microsporidia were detected at all sampling sites. Sequence analyses of ITS amplicons generated by using microsporidia-specific primers determined the presence of microsporidia in 87 samples including 13 humans; since two cases of simultaneous occurrence of Encephalitozoon cuniculi and Enterocytozoon bieneusi were identified, 89 full-length ITS sequences were obtained, namely 78 Encephalitozoon cuniculi genotype I, five E. cuniculi genotype II, two E. hellem 1A and four Enterocytozoon bieneusi. No Encephalitozoon intestinalis-positive samples were identified. This is the first report of Encephalitozoon species and Enterocytozoon bieneusi genotypes in captive great apes kept under various conditions and the first record of natural infection with E. hellem in great apes. A comparison of zoos and sanctuaries showed a significantly higher prevalence of microsporidia in sanctuaries (P<0.001), raising a question about the factors affecting the occurrence of microsporidia in epidemiologically and sanitarily comparable types of facilities.
Předkládaný článek přináší stručný průřez problematiky studia taxonomie štírů rodu Euscorpius. Evropským štírům byla věnována pozornost již od poloviny 18. století. Po bezmála 250 letech zkoumání se tento rod stále nedočkal vyřešení otázky své komplikované taxonomie. Zdá se ovšem, že současné studie kombinující morfologické, genetické a cytogenetické znaky mohou být klíčem pro odhalení skutečné druhové diverzity., This article briefly summarizes the last two and a half centuries of taxonomic research into the European genus of scorpions commonly known as small wood scorpions (Euscorpius). Despite the fact that taxonomists have been focusing on this genus since the mid-18th century, their taxonomy is not yet sufficiently resolved. However, present studies seem to be on the right track, and looking into a combination of morphological, genetic and cytogenetic features may hold the key to revealing the true diversity of the species., and Jana Plíšková.
In some economic or social division problems, we may encounter uncertainty of claims, that is, a certain amount of estate has to be divided among some claimants who have individual claims on the estate, and the corresponding claim of each claimant can vary within a closed interval or fuzzy interval. In this paper, we classify the division problems under uncertainty of claims into three subclasses and present several division schemes from the perspective of axiomatizations, which are consistent with the classical bankruptcy rules in particular cases. When claims of claimants have fuzzy interval uncertainty, we settle such type of division problems by turning them into division problems under interval uncertainty.
Periodická tabulka prvků má dlouhou historii, která je současně cestou předchemického a chemického bádání. Byla to cesta, jejímž cílem bylo vnést řád do světa hmoty. Zformování pojmu "chemický prvek" a následně atomové teorie vedlo k moderni chemii. Bylo jen otázkou času, kdy se podaří vnést systém do narůstajícího počtu známých prvků, až nakonec periodický zákon zformuloval Mendělejev. Dnes je otázkou nejen pokračování periodické tabulky a hledání případných "ostrovů stability", ale samozřejmě i naprosto zásadní problém - končí tabulka někde? and Vladimír Karpenko.
Pokles kyselé atmosférické depozice od 90. let minulého století a rovněž postupné oteplování klimatu bylo prokazatelně doloženo i pro horské ekosystémy v nejvyšších slovenských pohořích. Výzkumy epigeické aktivity mnohonožek (Diplopoda) v letech 1992-1993, 1997-1998, 2007-2008 a pokračující sledování v současnosti svědčí o rozmanitosti společenstev těchto půdních bezobratlých včetně přítomnosti řady karpatských endemitů v závislosti na odlišném geologickém podloží (žula a vápenec) a typu vegetace. Pozorovaný ústup chladnomilných endemitů i nárůst podílu eurytopních adaptabilních druhů lze dávat do souvislosti s probíhajícími změnami v chemismu půd i změnami klimatu., The decline of acid deposition since the 1990s, together with subsequent climate warming, was confirmed also for mountain ecosystems in the highest Slovak mountains. The study of epigeic activity of millipedes (Diplopoda) in the periods 1992-93, 1997-98 and 2007-08, and continuing recent research refer to the high diversity of their communities including the presence of Carpathian endemic species on different geological bedrocks (granite and limestone) as well as different vegetation covers. The observed decline of cold tolerant endemics and the increasing portion of eurytopic species may be connected with changes in soil chemistry as well as with climate changes., and Karel Tajovský.