From June to August in 2004 and 2005, we conducted the studies on spontaneous vocalization development of greater horseshoe bat, Rhinolophus ferrumequinum, in Zhi’an Village (Jilin province, Northeast China). In contrast to adult bats, infant bats of the greater horseshoe bat emitted calls characterized by multiharmonics and variable harmonic patterns. With the physical growth of infants, the dominant frequency, pulse duration and frequency of each harmonic of spontaneous calls increased, the number of harmonics decreased from 5–8 to 1–2 and dominant harmonic switched from first to the second with peak frequency increasing. Vocalizations of infant bats of the greater horseshoe bat could be categorized to those serving as precursors of echolocation sounds and those serving as isolation calls used to attract their mothers. According to observation on mother-infant reunion, the female adult bats only suckled their own babies, but not other pups in the same colony. And the mother recognized their own infants through both odor and vocal cues indicating that the isolation calls emitted by infant bats played an important role in mother-infant communication.
Vocalizations of the plaintive cuckoo (Cacomantis merulinus) and brush cuckoo (C. variolosus) were compared. Six major sound types were identified in the plaintive cuckoo, and four in the brush cuckoo. On the basis of song similarity as assessed by sonogram qualitatively and quantitatively, the grey-bellied cuckoo (C. passerinus) was considered conspecific with C. merulinus and the rusty-breasted cuckoo C. sepulcralis was considered conspecific with C. variolosus. The song similarities between C. merulinus and C. variolosus were considered homologous and derived from common ancestry.
The paper reported vocalizations of endemic Tibetan Plateau steppe sparrow, red- necked snow finch (Pyrgilauda ruficollis) by using SAS-Lab Pro. The subject similarity contrast and multivariate contrast were used to study the complexity and stability of sounds. The results indicated that songs of P. ruficollis were highly complicated with varied song types, song phrases, song syllable and combination of them. One song syllable shared by snow finches (Montifringilla nivalis henrici, M. adamsi, P. ruficollis and P. blanfordi) was selected as indicator to compare the taxonomic relationship among them. The similarity contrast and cluster analysis through SPSS were conducted to construct the similarity tree based on this shared syllable’s acoustic parameters including the highest frequency (HF), the lowest frequency (LF), the main frequency (MPF) and duration (DUR). The results revealed that the syllable similarities are accordant with taxonomic status suggested in previous studies based on morphologic, ecological and molecular analysis methods. The syllable shared by these snow finches were presumed to be homologous and derived from a common ancestry. Further studies on songs encoding phylogenetic signal of snow finches are needed.
The Muslim population´s growth rate in Southern Africa has been pretty slow, even though they have been in this part of the African continent for more than a century. With the passage of time, they adapted to the changing socio-political and economic circumstances and saw themselves as an integral part of the populations in this region. As the Muslims were gradually becoming economically mobile, they set up various structures such as mosques and welfare organizations that would serve the interest of their communities and thus achieve their communal goals. Some of them realized the role of the media as one of the most effective instruments to assist in their cause and these groups then established newpapers and radio stations in different parts of the region. In the latter part of the 20th century a fair number of the media have emerged and contributed towards the debates that have taken and are still taking place within in Southern Africa´s civil societies.
V práci je prezentovaná problematika tvorby vol'ných radikálov kyslíka, ich elektrónovej štruktúry, vlastností a metódy detekcie. Pozornosť je venovaná poškodzujúcemu účinku vol'ných radikálov na nukleové kyseliny, proteíny a biologické membrány., The article is dealing with the topic of oxygen-containing free radicals, their electronic structure, properties and methods of detection. Attention is paid to chemical and biochemical aspects of these free radicals, i.e., the sources of their generation, the metal-mediated formation of the reactive species and the damage to lipids, proteins and nucleic acids initiated by them., Klaudia Jomová, Ľubomír Zelenický, Vlasta Brezová, Marián Valko., and Obsahuje bibliografii
It is well known that antagonists of N-type voltage-gated calcium channels inhibit the evoked quan tal release of acetylcholine in amphibian neuromuscular synapses. This, however, does not exclude the functional expression of other types of voltage-gated calcium channels in these nerve terminals. Using immunocytochemistry, we detected the expression of the α1A subunit of P/Q-type calcium channels (that is otherwise typical of mammalian motor nerve endings) in the frog neuromuscular junction. In addition, we demonstrated that the P/Q-type channel blocker ω-agatoxin IVA (20 nM) reduced the action potential- induced calcium transient and significantly decreased both spontaneous and evoked mediator release. Our data indicates the functional expression of P/Q-type calcium channels in the frog motor nerve ending which participate in acetylcholine release., L. F. Nurullin ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The vagal motor fibers innervating the esophageal striated muscle are essential for esophageal motility including swallowing and vomiting. However, it is unknown which subtypes of voltagegated sodium channels (NaV1s) regulate action potential conduction in these efferent nerve fibers. The information on the NaV1s subtypes is necessary for understanding their potential side effects on upper gut, as novel inhibitors of NaV1s are developed for treatment of pain. We used isolated superfused (35 °C) vagally-innervated mouse esophagus striated muscle preparation (mucosa removed) to measure isometric contractions of circular striated muscle evoked by electrical stimulation of the vagus nerve. NaV1 inhibitors were applied to the de-sheathed segment of the vagus nerve. Tetrodotoxin (TTX) applied to the vagus nerve completely abolished electrically evoked contractions. The selective NaV1.7 inhibitor PF-05089771 alone partially inhibited contractions and caused a >3-fold rightward shift in the TTX concentration-inhibition curve. The NaV1.1, NaV1.2 and NaV1.3 group inhibitor ICA-121431 failed to inhibit contractions, or to alter TTX concentration-inhibition curves in the absence or in the presence of PF-05089771. RT-PCR indicated lack of NaV1.4 expression in nucleus ambiguus and dorsal motor nucleus of the vagus nerve, which contain motor and preganglionic neurons projecting to the esophagus. We conclude that the action potential conduction in the vagal motor fibers to the esophageal striated muscle in the mouse is mediated by TTX-sensitive voltage gated sodium channels including NaV1.7 and most probably NaV1.6. The role of NaV1.6 is supported by ruling out other TTX-sensitive NaV1s (NaV1.1-1.4) in the NaV1.7-independent conduction.
The aim of the following study is to analyze Voltaire’s biography about Charles XII as an early part of Voltaire’s historiographical work and also to analyze the ideas of the Enlightenment the author used. The study also tries to answer the question which lesson a reader should get and which interpretations should be on the other hand avoided., Martin Liška., and Obsahuje bibliografické odkazy
Using a microelectrode with carbon filaments and the voltammctric technique, changes evoked in the catechol oxidation current (CA.OC) and multiple unit activity (MUA) by microinjection of 3-5 ¿ri 03 mol.I'1 KC1 were studied in the reticular formation (RF) of the medulla oblongata of anaesthetized rats; the effect of KC1 stimulation of the RF and corpus striatum (S) on the CA.OC in these structures was compared. The microinjection of KC1 in the vicinity of the working electrode in the RF caused depression of MUA which began 2-3 s after administration, persisted for up to 6 min after and then diminished, reaching control values within 9 min. The voltammctric signal was first recorded in the 1st min after microinjection, when there was an evident decrease in the CA.OC value (59 % of the control value); this effect reached its maximum 7 min after administration (a mean drop to 23 % of the control), while at the end of the experiment (i.e. after 24 min) CA.OC values had risen to 45-80 % of the control value. The response in the S had a biphasic character, however. Immediately after the microinjection (1st min), the mean CA.OC value rose to 626 % of the control, while in the second phase (3-10 min) it was seen to fall below the control values (means 21-63 % of the control). The differences in the changes evoked by K+ depolarization in the concentration of catecholamines in the RF and S microenvironment are discussed from the aspect of the existence of different pools of the transmitter and
other regional differences. The possibility of a relationship between considered.