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14712. Chaetotaxy applied to Norwegian Gyrodactylus salaris Malmberg, 1957 (Monogenea) clades and related species from salmonids
- Creator:
- Bakke, Tor A., Nilsen, Kariann B., and Shinn, Andrew P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Gyrodactylus salaris, parasite, salmonids, taxonomy, and chaetotaxy
- Language:
- English
- Description:
- Gyrodactylus salaris Malmberg, 1957 is a major pathogen of wild Salmo salar L. parr populations in Norway, and its delimitation from non-pathogenic species is important. The present study was undertaken to test the power of chaetotaxy to differentiate between three populations belonging to both the same and different clades (as stated by mtDNA) of G. salaris, in addition to three different species of gyrodactylids (G. salaris, G. thymalli and G. caledoniensis). The gyrodactylids were processed for chaetotaxy in situ and a maximum of 50 specimens per collection site were used to construct a generalised map over the sensilla. The sensilla were found in all populations to be symmetrically distributed around the median longitudinal axis, according to a formula of 7 dorsal (34 sensilla) and 8 ventral (44 sensilla) clusters on each side of the median line. The three Norwegian populations of G. salaris were found identical, as were the population of G. thymalli. The specimens of G. caledoniensis from Scotland, however, were found to differ from the Norwegian species G. salaris and G. thymalli by the position of one sensillum in two of the clusters. A comparison of the sensillum pattern of laboratory maintained G. salaris (River Lierelva) with results obtained ten years earlier, questions the temporal stability of the chaetotaxy pattern. The present results indicate that chaetotaxy can be used to discriminate between certain Gyrodactylus spp. but not generally.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14713. Chaetotaxy of the monogeneans Macrogyrodactylus clarii and M. congolensis from the gills and skin of the catfish Clarias gariepinus in Egypt, with a note on argentophilic elements in the nervous system
- Creator:
- El-Naggar, Mohammed M., Arafa, Safaa Z., El-Abbassy, Sameer A., and Kearn, Graham C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenea, Macrogyrodactylus clarii, Macrogyrodactylus congolensis, surface sensilla, nervous system, chaetotaxy, and Clarias gariepinus
- Language:
- English
- Description:
- A comparison has been made between the chaetotaxy of the gyrodactylid monogeneans Macrogyrodactylus clarii Gussev, 1961 and M. congolensis (Prudhoe, 1957) Yamaguti, 1963 from the gills and skin, respectively, of the catfish Clarias gariepinus (Burchell) from the river Nile in Egypt. Bilaterally arranged argentophilic structures on the surface of these parasites are presumed to be sensilla and are more abundant in M. clarii than in M. congolensis especially on the ventral surface (124 vs. 66). In both species these sensilla are concentrated on the head lobes and in the pharyngeal region, but there are features of the sensilla patterns that can be used to distinguish the two species. Comparison is made with sensilla patterns of other gyrodactylids. A system of cells and dendritic processes, most probably part of the nervous system, also has an affinity for silver in the two species. There are no previous records of extensive argentophilic elements in the nervous systems of monogeneans.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14714. Chain correlation between variables of gas exchange and yield potential in different winter wheat cultivars
- Creator:
- Jiang, G. M., Hao, N. B., Bai, K. Z., Zhang, Q. D., Sun, J. Z., Guo, R. J., Ge, Q. Y., and Kuang, T. Y.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- apparent quantum yield of CO2 fixation, compensation irradiance, cultivars with high and low yield potentials, dark respiration, flag leaf, net photosynthetic rate, stomatal conductance, transpiration, and water use efficiency
- Language:
- Multiple languages
- Description:
- Variables of gas exchange of flag leaves and grain yield potentials of five representative winter wheat (Triticum aestivum L.) cultivars varied greatly across different development stages under the same management and irrigation. The cultivars with high yield potential had higher net photosynthetic rate (PN), PPFD (photosynthetic photon flux density) saturated photosynthetic rate (Psat), stomatal conductance (gs), and maximum apparent quantum yield of CO2 fixation (Φm,app) than those with low grain yield, but their dark respiration rate (RD) and compensation irradiance (Ic) were remarkably lower. Compared with overall increase of yield potential of 71 % from low yield cultivars to high yield ones, PN, Psat, Φm,app, and gs were 13, 19, 57, and 32 % higher, respectively; but RD and Ic decreased by 19 and 76 %, respectively. Such difference was evidently large during anthesis stage (e.g., PN by 33 %), which indicated that this period could be the best for assisting further selection for better cultivars. However, transpiration rate (E) and water use efficiency (WUE) differed only little. At different development stages, especially at anthesis, PN and Psat were positively correlated with Φm,app, gs, and yield potential, and negatively correlated with RD and Ic. Thus the high-yield-potential winter wheat cultivars possess many better characters in photosynthesis and associated parameters than the low-yield cultivars. and G. M. Jiang ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14715. Chalíl as-Sakákíní a jeho postoj k sionizmu pred rokom 1914
- Creator:
- Beška, Emanuel
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14716. Chalíl Džibrán: Písek a pěna
- Creator:
- Pantůček, Svetozár
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14717. Challenge of human factor influence for car safety
- Creator:
- Novák, Mirko and Votruba, Zdeněk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- interaction between driver and artificial system, reliability, transportation systems, training, EEG, and prediction diagnostics
- Language:
- English
- Description:
- Human society needs still more intensive exploitation of all kinds of transportation facilities. This need has already lasted for several decades and will be much more imperative in future. Mobility is one of the basic requirements for survival, besides the energy and food resources, health care and security. The requirements on transportation systems concern not only the quantitative and qualitative aspects of transportation activities, but still more also the aspects of their reliability and safety. This concerns not only the transported subjects or goods but also the environment. The losses caused by failures of transportation activities reach even now a very high level and if not limited by systematic research and preventive activity, they will reach quite a tremendous level soon. However, practically all the conternporary transportation vehicles, trains, ships and planes and also all the transportation systems need, for their proper operation, the interaction with human beings, which drive them, controls them or uses them and maintains them. In spite of the fact that significant progress was made in recent years as concerns the transportation systems automation, the fully automatic transportation systam in use is still foreseen in the considerably far future. Analyzing the reliability and safety of transportation, one finds that the activity of a human being is the weakest point. The technical reliability of almost all transportation tools has improved quite a lot in the past years; however, the human subject interacting with them has not changed too much, as for his/her reliability and safety of the respective necessary interaction. Therefore there is a vital necessity to improve it and the possibilities how to implement it will stay more and more in the focus of our interest. In this paper an overview of the related problems is made, the challenges for further research and development in this area are discussed and the outline of a vision, with respect to human interaction reliability, of optimized transportation systems is presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14718. Challenges and problems of neuroeconomics: several tasks for social scientists
- Creator:
- Müller, Michal
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- decision-making, methodology, neuroeconomics, philosophy of economics, philosophy of science, filosofie ekonomie, filosofie vědy, metodologie, neuroekonomie, and rozhodování
- Language:
- Czech
- Description:
- Neuroscience is a fascinating discipline – its dynamic progress has led to the emergence of new interdisciplinary research programmes with great potential. One of these research areas is neuroeconomics. As will be shown in this article, this discipline, which is diffi cult to clearly characterize and defi ne, is faced with many problems. Th is paper argues that social scientists should be interested in the problems and tendencies in social neuroscience for several reasons. Neuroeconomics, and other disciplines inspired by neuroscience, will compete with their parent disciplines in many fi elds of interest. On one hand it will be necessary for scientists to defi ne and defend the irreplaceable roles of their disciplines, but also critically evaluate the potential of new approaches on the other. In the context of this discussion, which reopens questions about the scientifi c status of economics and its roles, this paper introduces the main problems related to neuroeconomics. Th is paper concludes that these problems represent a wide domain for social scientists and methodologists of science. and Neurověda je fascinující disciplínou – její dynamický rozvoj podněcuje vznik nových interdisciplinárních výzkumných programů s velkým potenciálem. Jednou takovou oblastí je i neuroekonomie. Jak se ukáže v článku, tato disciplína, kterou je obtížné jednoznačně vymezit a určit její defi nici, se potýká se spoustou problémů. Článek y jj fi argumentuje, že by se společenští vědci měli těmito problémy a tendencemi v sociální neurovědě zabývat, a to hned z několika důvodů. Neuroekonomie, a také další neurovědou inspirované disciplíny, budou svým mateřským oborům konkurovat v mnoha oblastech, přičemž bude nezbytné, aby vědci byli schopni na jedné straně defi novat a obhájit nezastupitelné role svých disciplín, na straně druhé kriticky vyhodnocovat potenciál nových přístupů. V kontextu této diskuze, která znovu otevírá otázky ohledně vědeckého statusu ekonomie a jejích rolí, článek vymezuje základní problémy, s nimiž se neuroekonomie potýká. Práce dospívá k závěru, že tyto problémy představují široké pole působnosti pro společenské vědce a metodology vědy.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14719. Challenges of microsatellite development in Lepidoptera: Euphydryas aurinia (Nymphalidae) as a case study
- Creator:
- Sinama, Melthide, Dubut, Vincent, Costedoat, Caroline, Gilles, André, Junker, Marius, Malausa, Thibaut, Martin, Jean-François, Nève, Gabriel, Pech, Nicolas, Schmitt, Thomas, Zimmermann, Marie, and Meglécz, Emese
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Lepidoptera, microsatellite, null allele, 454 sequencing, QDD, Euphydryas aurinia, 2, and 59
- Language:
- English
- Description:
- Currently it remains difficult to obtain robust microsatellite markers for Lepidoptera. In an attempt to overcome the problems associated with developing microsatellite markers for this insect order we combined (i) biotin-enrichment protocol, (ii) next generation pyrosequencing (through 454 GS-FLX Titanium technology) and (iii) the use of individuals collected from eight geographically distant European populations representing three subspecies of Euphydryas aurinia. Out of 96 stringently designed primer pairs, 12 polymorphic microsatellite loci amplified without obvious evidence of null alleles in eight individuals from different subspecies. Between five and seven of these loci showed full within population applicability and three revealed to be robust and transferable between populations and sub-species, providing a first step towards the development of a valuable and robust tool for studying conservation issues and evolution in E. aurinia populations. Nevertheless, as in most studies dealing with Lepidoptera microsatellites, null alleles were detected in most of the developed markers. Our results emphasize the need for further research in order to better understand the complex evolution and organization of Lepidopteran genomes. and Melthide Sinama, Vincent Dubut, Caroline Costedoat, André Gilles, Marius Junker, Thibaut Malausa, Jean-François Martin, Gabriel Nève, Nicolas Pech, Thomas Schmitt, Marie Zimmermann, Emese Meglécz.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14720. Challenges to the theories of B stars circumstellar environment
- Creator:
- Krtička, J., Korčáková, D., and Kubát, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- stars: winds, stars: outflows, stars: mass-loss, stars: early-type, hydrodynamics, and instabilities
- Language:
- Czech
- Description:
- We review recent developments in the field of B stars circumstellar environment modelling and discuss future improvements which are necessary to obtain more realistic models of the circumstellar environment of B stars.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public