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10262. Unusual social calls of Nathusius´ pipistrelle (Vespertilionidae, Chiroptera) recorded outside the mating season
- Creator:
- Jahelková, Helena
- Type:
- article and TEXT
- Subject:
- Pipistrellus nathusii, vocalization, and modified calls
- Language:
- English
- Description:
- The advertisement calls of Nathusius’ pipistrelle (Pipistrellus nathusii) show an unified structure: three main motifs which can be supplemented with additional two motifs especially during mating season. In May and June, a continuous social vocalization of quite unusual structure and composition was recorded apart from these standard calls. Most of these calls were designed in a long “wavy line” pattern with the peak frequency of 14–36 kHz, and were accompanied by standard or modified echolocation calls. In one case we succeeded to supplement the acoustic records with a complete record of behavioural details: two bats slowly flew and followed one another in a circular path in front of the roost, where they repeatedly performed false landings, and during approaching one of them emitted the unusual social calls. This behaviour lasted for about 40% of the whole-night activity. The possible meaning is discussed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
10263. Unwanted Silesia: Czech ''Silesian Identity'' in postwar Czechoslovakia (1945-1969)
- Creator:
- Knapík, Jiří and Jirásek, Zdeněk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- historiography, North Moravian region, Silesia, and Petr Bezruč
- Language:
- English
- Description:
- The Czech ''Silesian identity'', obvious throughout the twentieth century, was based on a mixture of strong regional, even local, patriotism, which was determined by historical developments. This patriotism developed on the ethnically mixed territory of Czech Silesia (formerly Austrian Silesia). After the Second World War, this phenomenon was quickly revived, but unlike in the pre-war period, it took a clearly Czech national form. The territorial factor, by contrast, receded into the background. Behind this activity and new interpretation stood intellectual circles and institutions in Opava, some leading fi gures from Ostrava, and the Silesian Cultural Institute in Prague. In addition to cultural-educational activity, their efforts were concentratedon claiming some border areas of Polish and German Silesia as being historically Czech, and also on ensuring the distinctive administrative status of the territory of Silesia in Czechoslovakia, the seed of which they saw in the Ostrava branch of the Moravian National Committee (Zemský národní výbor) in Brno. During the Communist regime, according to the authors, the top state authorities showed an intentional lack of interest in the problems of Silesia when solving related economic and other questions. A consequence of this was a ''silencing of the offi cial sources'' about Silesia. In the 1950s, the ''Silesian-ness'' was condemned as a form of ''bourgeois nationalism'' and was identifi ed with the period of Czech-Polish national friction in the region. From the administrative point of view, Silesia was dissolved in the Ostrava area, later in the North Moravian Region, and was recalled practically only by artistic expressions of an ''Old Silesian-ness'', such as folklore and museum exhibitions. Silesian organizations and societies were, with few exceptions, dissolved or renamed and the newly established Silesian Research Institute in Opava had to orient its historical research chiefl y to the labour movement. The works of the poet Petr Bezruč (born Vladimír Vašek, 1867-1958) and his collection of verses, Slezské písně (Silesian Songs), presented a problem because of their questionable depiction of Silesian identity, and the publication of the complete collection led to disputes in cultural policy. The Ostrava-based arts and politics periodical Červený květ (Red Flower), which repeatedly included debates about regionalism, began to be published in the mid-1950s. At the end of the decade, however, the Communist Party launched a campaign against parochialism (lokálpatriotismus), which was refl ected also in the condemnation of publications seeking to exonerate the poems and ideas of Óndra Łysohorsky (born Ervín Goj, 1905-1989), who during the war promoted the theory of a ''Lach nation.'' In the 1960s, the local authorities and fi gures of Opava again began to emphasize the role of their town as a regional centre. During the Prague Spring of 1968, there were calls for the restoration of Silesian self-government, but that remained more or less limited to the Opava region, and consequently some ''Silesian'' cultural initiatives from this period were of greater importance.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10264. Update on the role of spinal cord TRPV1 receptors in pain modulation
- Creator:
- Spicarova, D., Nerandzic, V., and Jiří Paleček
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, mícha, spinal cord, hyperalgesia, capsaicin, TRPV1, 14, and 612
- Language:
- English
- Description:
- The structure, expression and function of the transient receptor potential vanilloid 1 (TRPV1) receptor were intensively studied since the cloning in 1997 and TRPV1 receptors are now considered to act as transducers and molecular integrators of nociceptive stimuli in the periphery. In contrast, spinal TRPV1 receptors were studied less extensively and their role in pain modulation is still not fully understood. This short review is a follow up on our previous summary in this area ( Spicarova and Palecek 2008). The aim was to review preferentially the most recent findings concerning the role of the spinal TRPV1 receptors, published within the last five years. The update is given on the expression and function of the spinal TRPV1 receptors, their activation by endogenous agonists, interaction between the endocannabinoid and endovanillod system and possible role of the spinal TRPV1 receptors in pathological pain states. There is now mounting evidence that TRPV1 receptors may be an important element in modulation of nociceptive information at the spinal cord level and represent an interesting target for analgesic therapy., D. Spicarova, V. Nerandzic, J. Palecek., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10265. Uplatnění polarografie ve fyzikálněchemickém výzkumu
- Creator:
- Pospíšil, Lubomír
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Heyrovský, Jaroslav, 1890-1967, 20. století, polarografie, fyzici, chemici, physicists, chemists, Česko, Czechia, čeští fyzici, čeští chemici, 10, and 544
- Language:
- Czech and English
- Description:
- Polarografická metoda umožňuje studium řady fyzikálněchemických problémů. Jsou uvedeny příklady z oblasti výzkumu struktury fázového rozhraní elektroda/roztok, adsorpce na povrchu elektrody, elektrochemického fotoefektu, fázových přechodů povrchových filmů, přenosu elektronu na molekulární vzdálenosti a oscilačních elektrochemických systémů., Polarography is a suitable method for solving numerous problems of physical chemistry. Examples from the following fields are given: structure of electrode/solution interfaces, adsorption on electrode surface, electrochemical photo-effect, phase transition of surface films, electron transfer over molecular distances, and electrochemical oscillating systems., Lubomír Pospíšil., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10266. Upper airway dilator muscle weakness following intermittent and sustained hypoxia in the rat: effects of a superoxide scavenger
- Creator:
- Skelly, J. R., Rowan, S. C., Jones, J. F. X., and O´Halloran, K. D.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, antioxidants, fatigue, hypoxia/re-oxygenation, intermittent hypoxia, superoxide scavenger, obstructive sleep apnoea syndrome, upper airway muscles, 14, and 612
- Language:
- English
- Description:
- Obstructive sleep apnoea syndrome (OSAS) is a common disorder associated with upper airway muscle dysfunction. Agents that improve respiratory muscle performance may have considerable therapeutic value. We examined the effects of acute exposure to sustained and intermittent hypoxia on rat pharyngeal dilator muscle function. Additionally, we sought to test the efficacy of antioxidant treatment in ameliorating or preventing hypoxia-related muscle dysfunction. Isometric contractile and endurance properties of isolated rat sternohyoid muscle bundles were examined at 35 °C in vitro. Muscle bundles were exposed to one of four gas treatments: hyperoxia (control), sustained hypoxia (SH), intermittent hypoxia (IH) or hypoxia/reoxygenation (HR), in the absence or presence of the superoxide scavenger – Tempol (10 mM). Stress-frequency relationship was determined in response to electrical stimulation (10-100 Hz in increments of 10-20 Hz, train duration: 300 ms). Muscle performance was also assessed during repetitive muscle stimulation (40 Hz, 300 ms every 2 s for 2.5 min). Compared to control, IH and HR treatments significantly decreased sternohyoid muscle force. The negative inotropic effect of the two gas protocols was similar, but both were of lesser magnitude than the effects of SH. SH, but not IH and HR, increased muscle fatigue. Tempol significantly increased sensitivity to stimulation in all muscle preparations and caused a leftward shift in the stressfrequency relationship of IH and SH treated muscles. Tempol did not ameliorate sternohyoid muscle fatigue during SH. We conclude that Tempol increases upper airway muscle sensitivity to stimulation but only modestly ameliorates respiratory muscle weakness during intermittent and sustained hypoxic conditions in vitro. Respiratory muscle fatigue during sustained hypoxia appears unrelated to oxidative stress., J. R. Skelly, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10267. Upper bounds on the node numbers of hidden layers in MLPs
- Creator:
- Liu, Jiang, Ni, Feng, Du, Mingjun, Zhang, Xuyang, Que, Zhongli, and Song, Shihang
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- feedforward neural network, hidden node, multilayer perceptron (MLP), and upper bound
- Language:
- English
- Description:
- It is one of the fundamental and challenging problems to determine the node numbers of hidden layers in neural networks. Various efforts have been made to study the relations between the approximation ability and the number of hidden nodes of some specific neural networks, such as single-hidden-layer and two-hiddenlayer feedforward neural networks with specific or conditional activation functions. However, for arbitrary feedforward neural networks, there are few theoretical results on such issues. This paper gives an upper bound on the node number of each hidden layer for the most general feedforward neural networks called multilayer perceptrons (MLP), from an algebraic point of view. First, we put forward the method of expansion linear spaces to investigate the algebraic structure and properties of the outputs of MLPs. Then it is proved that given k distinct training samples, for any MLP with k nodes in each hidden layer, if a certain optimization problem has solutions, the approximation error keeps invariant with adding nodes to hidden layers. Furthermore, it is shown that for any MLP whose activation function for the output layer is bounded on R, at most k hidden nodes in each hidden layer are needed to learn k training samples.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10268. Upregulation of genes involved in cardiac metabolism enhances myocardial resistance to ischemia / reperfusion in the rat heart
- Creator:
- Ravingerová, T., Slávka Čarnická, Ledvényiová, V., Barlaka, E., Galatou, E., Chytilová, A., Mandíková, P., Nemčeková, M., Adriana Adameová, František Kolář, and Lazou, A.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, apoptóza, apoptosis, myocardial ischemia, delayed preconditioning, RRAR activation, metabolic genes, WY-14643, 14, and 612
- Language:
- English
- Description:
- Genes encoding enzymes involved in fatty acids (FA) and glucose oxidation are transcriptionally regulated by peroxisome proliferator-activated receptors (PPAR), members of the nuclear receptor superfamily. Under conditions associated with O 2 deficiency, PPAR-α modulates substrate switch (between FA and glucose) aimed at the adequate energy production to maintain basic cardiac function. Both, positive and negative effects of PPAR-α activation on myoc ardial ischemia/reperfusion (I/R) injury have been reported. Moreover, the role of PPAR-mediated metabolic shifts in cardioprotective mechanisms of preconditioning (PC) is relatively less investigated. We explored the effects of PPAR-α upregulation mimicking a delayed “second window” of PC on I/R injury in the rat heart and potential downstream mechanisms involved. Pretreatment of rats with PPAR-α agonist WY-14643 (WY, 1 mg/kg, i.p.) 24 h prior to I/R reduced post-ischemic stunning, arrhythmias and the extent of lethal injury (infarct size) and ap optosis (caspase-3 expression) in isolated hearts exposed to 30-min global ischemia and 2-h reperfusion. Protection was associated with remarkably increased expression of PPAR- α target genes promoting FA utilization (medium-chain acyl-CoA de hydrogenase, pyruvate dehydrogenase kinase-4 and carnitine palmitoyltransferase I) and reduced expression of glucose transporter GLUT-4 responsible for glucose transport and metabolism. In addition, enhanced Akt phosphorylation and protein levels of eNOS, in conjunction with blunting of cardioprotection by NOS inhibitor L-NAME, were observed in the WY-treated hearts. Conclusions: upregulation of PPAR-α target metabolic genes involved in FA oxidation may underlie a delayed phase PC-like protection in the rat heart. Potential non-genomic effects of PPAR-α-mediated cardioprotection may involve activation of prosurvival PI3K/Akt pathway and its downstream targets such as eNOS and subsequently reduced apoptosis., T. Ravingerová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10269. Uptake, reflux, and excretion of bromosulfophthalein in ischaemia-reperfusion injury of rat liver
- Creator:
- Kukan, M., Bezek, Š., and Trnovec, T.
- Type:
- article, model:article, and TEXT
- Subject:
- ischaemia, reperfusion, liver, and bromosulfophthalein uptake, reflux, excretion
- Language:
- English
- Description:
- The uptake, reflux and excretion of bromosulfophthalein (BSP) were studied on a model of total warm ischaemia for 30 min (group 1) or 60 min (group 2) followed by reperfusion for 45 min in the isolated perfused rat liver of unfasting rats. In group 1, the BSP hepatic uptake was comparable to control livers (30 s ischaemia plus 45 min reperfusion), but was significantly reduced in group 2. The reflux of BSP from liver to perfusate in group 1 and group 2 resulted in the appearance of secondary concentration time peaks of BSP in the reservoir perfusate. This result suggests that ischaemia-reperfusion induced a qualitative change in BSP pharmacokinetics. Excretion of the dye into bile was significantly impaired in group 2 only. The leakage of lactate dehydrogenase into the perfusate was increased moderately in both group 1 and group 2 in comparison to the controls, suggesting a low degree of liver parenchymal injury. In conclusion, the results of this investigation showed that BSP pharmacokinetics were not only undergoing quantitative changes but also a qualitative change in the model of ischaemia-reperfusion injury of the liver obtained from fed rats and may thus serve as a highly sensitive indicator of liver viability.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10270. Úřad moravského zemského hejtmana za posledních Lucemburků (1411-1423)
- Creator:
- Svoboda, Josef
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- moravian land captain, margravate of Moravia, 15th century, and Hussitism in Moravia
- Language:
- Czech, English, and German
- Description:
- This study deals with the changes in position of the office of moravian land captain during the reign of last members of house Luxemburg in Moravia, since the ascension of king Venceslaus IV. in the year 1411, over the reign of Sigismund of Hungary, to the granting of Moravian margravate to Albrecht V. of Habsburg in october 1423. The author corrects some deficiencies of existing literature and specifies the chronology of holders of this office. Based on the analysisi of sources are also reconstructed purviews and areas, in which the land captain could intervene and their changes in time of hussite wars and reign of different margraves. This work also captures the way of appointment and deposition of land captains by the ruler and different strategies and attempts to alternate arrangement of administration of Moravian margravate by Sigismund of Hungary, when he tried to sideline this office, which became more and more dependent on the forming high nobility estate.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public