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31822. Three species of Calydiscoides (Monogenea: Diplectanidae) from five Lethrinus spp. (Lethrinidae: Perciformes) off New Caledonia, with a description of Calydiscoides terpsichore sp. n.
- Creator:
- Rascalou, Guilhem and Justine, Jean-Lou
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenea, Diplectanidae, Calydiscoides difficilis, Calydiscoides duplicostatus, Calydiscoides terpsichore, Lethrinus, host specificity, and South Pacific
- Language:
- English
- Description:
- Numerous specimens of Calydiscoides spp. from Lethrinus nebulosus and L. harak, and fewer specimens from L. lentjan, L. ravus and L. obsoletus, collected off New Caledonia, South Pacific, were examined. Three species of Calydiscoides were recognized. Calydiscoides difficilis (Yamaguti, 1953) Young, 1969 was generally the most abundant species on the five hosts. Specimens of C. difficilis were measured and compared to the type specimens (from Indonesia) and museum vouchers (from Australia and the Arabian Gulf). The morphology of the massive male copulatory organ and of haptoral sclerotized parts was similar, but specimens from the same host and from different hosts showed wide morphometric variations; it is concluded that C. difficilis has a high degree of variability, although the possibility of a species complex remains. Calydiscoides duplicostatus (Yamaguti, 1953) Young, 1969 was found on L. nebulosus, L. harak and L. lentjan; specimens were homogeneous in the three hosts and similar to the type specimens. Calydiscoides terpsichore sp. n. is described from L. nebulosus (type host) and L. harak and was uncommon in both fish. The new species, a member of the 'australis group', is characterized by its Y-shaped male copulatory organ, with the left branch bearing a trifurcated secondary branch. Lethrinus nebulosus and L. harak shared the 3 species of Calydiscoides studied here, a fact probably related with their close phylogenetic relationships. Among the 15 species of Lethrinus present in New Caledonia, 11 were examined and 9 species harboured 1-3 species of Calydiscoides each. Only 7 species of Calydiscoides were found, due to their stenoxenous specificity. Each species of Calydiscoides has 1 to 5 hosts.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31823. Three species of Magnibursatus Naidenova, 1969 (Digenea: Derogenidae) from Atlantic and Black Sea marine teleosts
- Creator:
- Kostadinova, Aneta, Power, Anne Marie, Fernández, Mercedes, Balbuena, Juan Antonio, Raga, Juan Antonio, and Gibson, David I.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Digenea, Magnibursatus, key to species, and marine fish
- Language:
- English
- Description:
- Three species of Magnibursatus Naidenova, 1969 are described from marine teleosts: M. skrjabini (Vlasenko, 1931), the type species of the genus, from the gobiid Zosterisessor ophiocephalus on the Bulgarian Black Sea coast; M. bartolii sp. n. from the sparid Boops boops off the Atlantic coast of Spain; and M. minutus sp. n. from the gobiid Neogobius eurycephalus on the Bulgarian Black Sea coast. M. bartolii differs from all other Magnibursatus species in its larger sinus-sac (length >250 µm, width >150 µm) and the more posterior location of testes. This species is also unusual in that it occurs in the branchial chamber and on the gills of its host. M. minutus is distinguished by the distinctly smaller dimensions of the body (length <1000 µm, width <200 µm), organs and eggs. These species are also distinguished from both M. caudofilamentosa (Reimer, 1971) and Tyrrhenia blennii Paggi et Orecchia, 1975. A key to the species of Magnibursatus is presented.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31824. Three substrate binding sites on spinach ferredoxin:NADP+ oxidoreductase. Studies with selectively acting inhibitors
- Creator:
- Bojko, M. and Więckowski, S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- apoferredoxin, cytochrome c, diaphorase activity, dibromothymoquinone, ferredoxin, and phenylmercuric acetate
- Language:
- Multiple languages
- Description:
- The effects of phenylmercuric acetate (PMA) and apoferredoxin (apoFd) on the diaphorase activity of spinach ferredoxin:NADP+ oxidoreductase (FNR) in the presence of dibromothymoquinone (DBMIB) or cytochrome c (Cyt c) were studied. PMA inhibited effectively (I50 = < 5 μM) ferredoxin-dependent Cyt c reduction but did not affect evidently the enzyme activity in the presence of DBMIB as an electron acceptor. ApoFd caused also inhibition of Cyt c reduction but slightly stimulated, like ferredoxin, DBMIB reduction. We confirm a hypothesis according to which three binding sites for substrates [NADP(H), Fd-Cyt c, quinone/dichlorophenol indophenol] occur within the molecule of isolated FNR. and M. Bojko, S. Więckowski.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31825. Three-dimensional electrogram in spherical coordinates: application to ischemia analysis
- Creator:
- Oto Janoušek, Kolářová, J., Marie Nováková, and Ivo Provazník
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ischemie, ischemia, three dimensional electrogram, vectorcardiogram, spatiocardiogram, vectorcardiography parameters, myocardial ischemia, 14, and 612
- Language:
- English
- Description:
- Three-dimensional electrogram was used for analysis of ischemia manifestation in isolated hearts. Three parameters based on spherical coordination system were used in this study - amplitude of electrical heart vector, its azimuth and elevation. The parameters were presented as a trend. This approach reflected ischemic changes in a manner which can be easily observed and evaluated. Ischemia was analysed in seven isolated hearts of New Zealand white rabbits. It was found that (a) ischemia changes heart electric vector, (b) ischemic preconditioning has a protective effect, and (c) both of these findings can be clearly observed by the proposed method., O. Janoušek ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31826. Three-dimensional flow of an Oldroyd-B fluid over a bidirectional stretching surface with prescribed surface temperature and prescribed surface heat flux
- Creator:
- Hayat, Tasawar, Shehzad, Sabir Ali, Al-Mezel, Saleh, and Alsaedi, Ahmed
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- three-dimensional flow, Oldroyd-B fluid, bidirectional stretching surface, and heat source/sink
- Language:
- Slovak
- Description:
- This paper concentrates on the mathematical modelling for three-dimensional flow of an incompressible Oldroyd-B fluid over a bidirectional stretching surface. Mathematical formulation incorporates the effect of internal heat source/sink. Two cases of heat transfer namely the prescribed surface temperature (PST) and prescribed surface heat flux (PHF) are considered. Computations for the governing nonlinear flow are presented using homotopy analysis method. Comparison of the present analysis is shown with the previous limiting result. The obtained results are discussed by plots of interesting parameters for both PST and PHF cases. We examine that an increase in Prandtl number leads to a reduction in PST and PHF. It is noted that both PST and PHF are increased with an increase in source parameter. Further we have seen that the temperature is an increasing function of ratio parameter.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31827. Thulium-doped fibers and fiber-optic components for fiber lasers at around 2 µm
- Creator:
- Peterka, Pavel, Honzátko, Pavel, Kašík, Ivan, Podrazký, Ondřej, Todorov, Filip, Cajzl, Jakub, Koška, Pavel, Baravets, Yauhen, Aubrecht, Jan, and Mrázek, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fiber lasers, thulium, cladding pumping, vláknové lasery, holmium, and čerpání přes plášť (cladding pumping)
- Language:
- Czech
- Description:
- Fiber lasers are the youngest and most rapidly developing branch of lasers. Golden era of fiber lasers started only in early 2000’s and followed success of fiber amplifiers in telecommunications in nineties. Nowadays, the ytterbium fiber lasers at around 1 μm are the most powerful lasers available, reaching 100 kW of average output power. The 2 μm class fiber based on thulium-doped fibers are getting increasing importance thanks to better eye-safety, relaxed non-linear limits, more efficient processing of various materials, e.g., plastics, and high slope efficiency of up to 70 %. In the paper we review our recent progress in research of novel host materials for enhancements of fluorescence properties of thulium-doped fibers and new fiber-optic components and their applications in monolithic thulium-doped fiber laser. Results of coherent combination of thulium-doped fiber lasers are also presented. and Vláknové lasery patří mezi nejmladší a nejrychleji se rozvíjející typy laserů. Zlatá éra vláknových laserů začala teprve na začátku nového tisíciletí a navazuje na úspěch vláknových zesilovačů v telekomunikacích v devadesátých letech. Ytterbiem dopované vláknové lasery na vlnových délkách v okolí 1 μm jsou v současnosti vůbec nejvýkonnějšími dostupnými lasery, dosahují až 100kW průměrného výstupního výkonu. Vláknové lasery na 2 μm založené na thuliem dopovaných optických vláknech získávají nyní na významu díky menšímu riziku poškození zraku, menším omezením kvůli nelinearitám, vysoké účinnosti dosahující až 70 % a efektivnějšímu opracovávání některých materiálů, např. plastů. V příspěvku shrnujeme některé naše nedávné výsledky v oblasti výzkumu nových typů materiálů pro zlepšení fluorescenčních vlastností thuliem dopovaných vláken, nových typů vláknových optických součástek a jejich použití v monolitickém vláknovém laseru. Popisujeme rovněž výsledky výzkumu koherentního kombinování thuliem dopovaných vláknových laserů.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31828. Thylakoid membrane protein kinase activity as a signal transduction pathway in chloroplasts
- Creator:
- Misra, A. N. and Biswal, A. K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- D1 protein, evolution, gene expression, light-harvesting complex 2, phosphorylation, and photosystems
- Language:
- Multiple languages
- Description:
- In plants external stimuli are perceived through a cascade of signals and signal transduction pathways. Protein phosphorylation and de-phosphorylation is one of the most important transduction paths for the perception of signals in plants. The highest concentrations of plant phospho-proteins are located in chloroplasts. This facilitates the protection of thylakoid membranes from stress-induced damage and augments adaptive strategies in plants. In this review, the protein kinases associated with phosphorylation of thylakoid membrane protein, and the adaptive changes in thylakoid membrane architecture and developmental cues are given. The presence of membrane bound kinases in thylakoid membranes have evolutionary implications for the signal transduction pathways and the photosynthetic gene expression for thylakoid membrane protein dynamics. and A. N. Misra, A. K. Biswal.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31829. Thylakoid membranes fragmentation by means of different detergents during leaf ontogeny
- Creator:
- Wilhelmová, N.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Ability of detergents digitonin (Dg), Triton X-IOO (TX), sodium dodecylsulphate (SDS), cetylpyridinium chloride (CPC), and Zwittergents 3-12 (Z-12), 3-14 (Z-14), and 3-16 (Z-16) to fragment unstacked thylakoid membranes was tested in French beán (Phaseolus vulgaris L.) leaves differing in age. The power of selected detergents to initiate fragmentation did not differ with different Chemical structure and molecular size of detergents, but it was controlled more probably by their molecular charge and shape. Unfavourable was the presence of positive charge and the absence of alkyl chain in detergent molecule. Membrane fragments obtained after the action of individual detergents on agranal thylakoids were separated on a Percoll gradient. Separated fractions were characterized by their chlorophyll (Chl) content, Chl a/b and Chl/protein ratios, position of absorption maximum (A^gx) i” spectral region and ratios of intensities of fluorescence emission bands. Since separation of no Chl-protein was achieved, no priority of detergent binding to any membrane component occurred under the conditions ušed. Fractions of similar density, products of the action of low concentrations of different detergents on the chloroplasts from leaves of the same age, differed in their characteristics. Low concentrations of detergents fragmented agranal membranes in a pattem which changed during leaf ontogeny. Only Z-16 had an increased capacity to extract proteins from membrane; this was probably promoted by the presence of 16-C alkyl chain.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31830. Thymus lipids in continuously irradiated rats
- Creator:
- Ahlers, I., Ahlersová, E., Toropila, M., and Ďatelinka, I.
- Type:
- article, model:article, and TEXT
- Subject:
- rats, continuous irradiation, and thymus lipids
- Language:
- English
- Description:
- Male Wistar rats were irradiated continuously with a daily dose of 0.19 Gy (120 days), 037 Gy (90 days) and 0.96 Gy (35 days) of gamma rays. An other group of rats was irradiated continuously with graded doses of gamma rays, up to total exposures ranging from 3.83-19.15 Gy. Depending on both the daily dose and total exposure, there was a decrease in phospholipid content in the thymus which correlated well with thymus weight changes. The decrease in triacylglycerol content was a less reliable sign of radiation damage. The phospholipid content reflecting the patterns of organ cellularity is a valuable indicator of the extent as well as recovery from radiation - induced injury to the thymus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public