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Polyploid speciation of the genus Anthoxanthum in Europe
Khodlová, Zuzana ; Trávníček, Pavel (advisor) ; Štech, Milan (referee)
Eight of fifteen species in genus Anthoxanthum (Poaceae) can be found in Europe. Five of them are perennials forming A. odoratum complex, the remaining three are annual, more or less mediterranean taxa (A. aristatum, A. ovatum and A. gracile). Within the A. odoratum s. l. complex the following taxa are distinguished: widely spread A. odoratum s. str. (4x; 2n = 20), arcto-alpine A. alpinum (2x a 4x; 2n = 10 and 20), Madeiran endemic species A. maderense (2x; 2n = 10), endemic species of Balkan mountains A. pauciflorum (2x; 2n = 10) and the Iberian peninsula endemic A. amarum (?x; 2n ~ 90). The aim of this thesis is to clearify the unknown evolutionary relationships between the taxa, between the annuals and perennials, diploids and polyploids. The following questions should be answered in this study: 1) What is the origin and distribution of the rediscovered diploid perennial taxon and what is its relationship to the other members of the group; 2) What is the distribution pattern of the perennial taxa of the genus Anthoxanthum in Europe and what is their haplotype differenciation (overall distribution of the taxa and haplotypes and the existence of their sympatric occurence); 3) What evolutionary ties exist among the species and what is the origin of allotetraploid taxon A. odoratum s.str. The...
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Microevolutionary processes and inter-cytotype interactions in mixed-ploidy populations
Trávníček, Pavel ; Suda, Jan (advisor) ; Frajman, Božo (referee) ; Zozomová, Judita (referee)
[Abstract] This thesis is aimed at better understanding of cytotype co-existence in mixed- ploidy populations with an emphasis on a microevolutionary processes behind it. Our past knowledge was based on a few thoroughly investigated model taxa like Chamerion angustifolium and Heuchera grossulariifolia, but some generalizations seem to be premature in the light of new findings. A detailed research of other taxa included in the thesis showed that polyploid complexes can vary dramatically in their ability to cope with the co-existence of cytotypes in mixed-ploidy popu- lations. Whereas mixed-ploidy populations are virtually lacking in some species (an example being Vicia cracca, Paper III.), ploidy-heterogeneous populations are very common in others, maintained by free mating interactions and the absence of reproductive isolation among cytotypes (e.g. Pilosella echioides, Paper II.). The strenght and cumulative effect of various breeding barriers (both pre- or post- zygotic) govern the position of a particular multi-ploidy complex between these two extremes and co-determine the type of cytotype co-existence in its mixed- ploidy populations. Despite the fact that the number of studies revealing cytotype co-existence has been increasing rapidly, evolutionary background and consequences of such co-...
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Watermilfoils (Myriophyllum) in the central Europe
Hrdinová, Magdalena ; Trávníček, Pavel (advisor) ; Prančl, Jan (referee)
Genus Myriophyllum L. (watermilfoil) belongs to one of the most species-rich genera within Haloragaceae (Saxifragales). It includes three invasive species, which are of major concern - European M. spicatum L., North American M. heterophyllum MICHX. and South American M. aquaticum (VELL.) VERDC. All of them occur in Central Europe as well as native M. verticillatum L. and M. alterniflorum DC. lacking more significant invasive growth up to now. It is not only its invasivness that makes genus Myriophyllum so fascinating. It also displays extremely high phenotypic plasticity which is accompanied by determination difficulties. Moreover, recent research indicates that Myriophyllum tends to hybridize producing more invasive hybrids than parental taxa. Such traits pose a formidable challenge to scientists to deal with possible future invasive growth of non-indigenous Myriophyllum species in Central Europe. Therefore, thorough study of factors influencing evolution success of plants should be conducted. One of the key factors seems to be polyploidy. Research into polyploidy offers a new approach to watermilfoil issues. Additionally, according to preparatory study all native Central European Myriophyllum species can be easily distinguished by flow cytometry. That enables to study polyploidy in an...
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Hiking Activities for Children of a Young School Age
Trávníček, Pavel ; Kašpar, Ladislav (advisor) ; Chrzanowská, Babeta (referee)
Dnešní doba nabízí nepřeberné množství služeb, které mají za cíl spokojeného klienta. Volný čas lze trávit tolika způsoby, kolik je jen oblastí lidského zájmu. V mnoha případech se z člověka stává holý konzument, který si neodnáší žádné prožitky. Aktivity v přírodě jsou jednou z alternativ využití volného času. Mezi aktivity v přírodě patří turistika, sporty v přírodě a jiné aktivity, které jsou spjaty s uvědomělým a šetrným využíváním přírodního prostředí. Turistika je cesta, na které se člověk navrací ke své původní hlubší propojenosti s přírodou, a která ho učí nepřestávat vnímat. Turistika je určitý řád hodnot a pocit svobody. Dětská bytost se utváří na základě mnoha podnětů. To co do dítěte vložíme, v něm zůstává celý život. Turistika dětí je jednou z možností výchovy a formování dětské osobnosti a příležitostí, jak vytvořit pro dítě základní představu podoby kvalitně prožitého času. Práce má za cíl podat čtenáři základní přehled o turistice dětí v České republice. Seznamuje čtenáře stručně s historií turistiky na našem území. Přináší současný pohled na organizovanou a neorganizovanou podobu turistiky a rozčleňuje turistiku na jednotlivá turistická odvětví, která rozvádí zpravidla s ohledem na dětského turistu.
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PMD - polarization mode dispersion and its effects on data transport
Trávníček, Pavel ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
My graduation thesis is concerned with the effect of polarization mode dispersion on transmitted signal by optical line. It describes external and internal causes of origination of polarization mode dispersion. On the basis of these effects there is a differential group delay (DGD). It is the time delay in meantime within individual modes. DGD results in a time extension of impulsion and limitation of maximum bit rate. This thesis contains localization methods of part of gossamer filament with increased value of PMD by POTDR method. This method is based on the principium of back dispersion and its modifications SOP a DOP. Very important chapter of this thesis is the measurement of the polarization mode dispersion. There are described methods of PMD measurement. It is the interferometric and polarimetric method and the method of state of polarization. The major part of this thesis is about the reduction of polarization mode dispersion effect. This part is divided into two parts. First part is about the methods of PMD effect reduction and the second one is about the PMD compensation. The discrepancy between these two parts is the reduction way of PMD effect on transmitted channel. The compensation use the compensation components inserted into the transmission path. By PMD reduction methods we can solve the problems from the view of changing of fibre or all cable. For better understanding of polarization mode dispersion effect there are simulated 4 optical lanes of various parameters. The simulation output is the eye diagram which provides the view at results of transmission lane. In the final part there is the evaluation of measured parameters of optical lanes simulated in a laboratory.
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L-DEPP Definition Study for Lunar Lander FINAL REPORT "
Trávníček, Pavel M. ; Štverák, Štěpán ; Hellinger, Petr ; Herčík, David ; Laifr, Jaroslav ; Pavelka, Roman ; Váňa, P. ; Břínek, J. ; Kozáček, Z. ; Rucker, H. ; Sampl, M. ; Auster, U. ; Glassmeier, K. - H. ; Kataria, D. ; Owen, C. J. ; Farrell, W.M. ; MacDowall, R. J. ; Sternovsky, Z. ; Horanyi, M. ; Delory, G.T. ; Turin, P.
A complete set of scientific instrumentation for the L-DEPP dust, plasma and waves package for the ESA Lunar Lander mission has been proposed and fully assessed with respect to the system and scientific requirements derived by ESA and the L-DEPP project team. The preliminary design from the system level down to the individual sensors is presented.
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