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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Intraindividuální komparace vybraných koordinačních ukazatelů bruslařského kroku na ledě a při in-line / Intraindividual comparison of selected indicators of coordinating steps on the skating step and on the in-line step

Hospůdka, Jakub January 2010 (has links)
4 Summary: Title: Intraindividual comparison of selected indicators of coordinating steps on the ice skating and in-line. Objective: Assessment of coordination relationship rate of the skating forward during ice hockey and inline skating. Methods: Surface electromyography combinated with kinematography analysis used synchronized video recording. Results: Kinesiological content of movement during ice skating and inline skating is not the same. The general stereotype of the skating step is significantly different from the walking stereotype. Key words: human locomotion, sport locomotion, phylogeny, ontogeny, surface electromyography, ice hockey skating, inline skating.
12

Morfogeneze orálního skeletu mihule ve vztahu k evoluci čelistí / Morfogeneze orálního skeletu mihule ve vztahu k evoluci čelistí

Romášek, Marek January 2012 (has links)
4 Neural crest-derived cellular cartilage is one of the defining characteristics of vertebrates. Elaboration of this tissue and its patterning allowed the evolution of jaws in the gnathostome lineage. Together these hallmarks helped jawed vertebrates become one of the dominant taxons in the animal kingdom. Lampreys, as basal jawless vertebrates, lie at a unique phylogenetic position that makes them ideal organisms for the study of evolution of vertebrate/gnathostome novelties. Larval lampreys possess a special oral skeleton composed of a tissue related to cartilage, termed mucocartilage. Despite considerable attention that has been paid to the evolutionary significance of mucocartilage, it is not yet clear, how this unique feature arises in development and to what extent it is homologous to gnathostome jaws. In this study, the development of oro-pharyngeal region was analyzed in the sea lamprey Petromyzon marinus. SEM imaging revealed shaping and topographic relationships of embryonic tissues, detailed plastic histology coupled with expression analyses of several molecular markers were used to describe origin, histogenesis and morphogenesis of mucocartilage. Furthermore, genetic regulation of the tissue was investigated in order to identify its unique or shared features. Mucocartilage is seen to...
13

Ontogenetický vývoj eokrinoidních ostnokožců kambria barrandienské oblasti / Ontogenetic development of Cambrian eocrinoid echinoderms of the Barrandian area

Nohejlová, Martina January 2013 (has links)
This diploma thesis presents the first study focused on the ontogenetic development of eocrinoid echinoderms in the Czech Republic. Parsley's work (2012) on ontogeny of the genus Gogia from south China is the model study. The aim of this thesis is a comparable study of ontogeny of eocrinoid echinoderms from Cambrian of the Barrandian area. Akadocrinus jani Prokop, 1962 was studied. Using detailed morphological description and measurement of various parameters, three different ontogenetic stages have been established: juvenile ontogenetic stage, mature ontogenetic stage and gerontic ontogenetic stage. Thecal height is the deciding factor for the determination of the specific ontogenetic stage. Further, during ontogeny of this species some trends in changes in the size of body parts are observed (e.g., changes in the diameter of thecal plates). In-depth study of morphological details showed that the originally distinguished two species, Akadocrinus jani Prokop, 1962 and Akadocrinus nuncius Prokop, 1962, represent one species only. Keywords: eocrinoid echinoderms, Akadocrinus jani, ontogeny.
14

Vliv teploty vody a intenzity světla na raný vývoj sumečka afrického v komerčním chovu

PROKEŠOVÁ, Markéta January 2016 (has links)
The successful production of quality early fish stages is crucial for artificial rearing fish species. Nevertheless, it is quite a problematic process, because fish as poikilothermic organisms are highly sensitive to various environmental conditions. Moreover, both fish embryos and larvae are more affected by biotic and abiotic factors (such as predation, stocking density, temperature, light, pH, salinity, oxygen saturation, feeding availability, or their interactions) than older juveniles or adults. Most fish processes such as reproduction, metabolism, survival, development and growth can be considerably (positively, negatively or not) influenced by these conditions. Therefore, it is important to understand their impacts on fish stages during embryonic, larval, juvenile, adult, and eventually the senescent period. Then, following the application of new knowledge to the practise, especially species- and age-specific optimal conditions, should result in higher survival, better growth rate, well developed fish without deformities and lower cannibalism. The objectives of the present thesis were to assess the effect of water temperature and light intensity on the early development (embryonic and larval period) of African sharptooth catfish as a perspective fish species for freshwater intensive aquaculture. Due to its great characteristics (for instance fast growth, ability to breathe atmospheric air, rearing at high stocking density) this species can meaningfully contribute to the global aquaculture production which is expected to rise in the coming years. However, there are still some difficulties in the early rearing African sharptooth catfish regarding the cannibalism, feeding, survival and necessity of detailed information about the effects of some abiotic factors and their interactions.
15

Změny látkového složení listoví smrku během jejich ontogense

Vitamvásová, Dagmar January 2000 (has links)
No description available.
16

Diferenciace totipotentních zárodečných buněk u larev ptačích schistosom / Differentiation of totipotent germinal cells in larvae of bird schistosomes

Peštová, Jitka January 2015 (has links)
This thesis aims to explore the larval development of a bird fluke Trichobilharzia regenti in its intermediate hosts, as well as the processes of differentiation of its embryonal cells and the differentiation between sporocystogenesis and cercariogenesis in sporocysts, with the ultimate goal to find out whether it is possible to find multiple generations of daughter sporocysts throughout the development of avian schistosomes in the intermediate hosts, just like in the case of human schistosomes of genus Schistosoma. Five developmental stages of daughter sporocysts, and ten developmental stages of cercariae have been defined. The first developmental stage in both larvae is the germinal cell. It divides and gives rise to a cell agregate. Afterwards an envelope (primitive epithelium) is formed around the embryo and subsequently, the embryo elongates. At this stage, the development of the two larvae undergoes different pathways. We can distinguish daughter sporocyst from cercaria in the phase, when the tegument is completed. The daughter sporocyst acquires characteristic vermiform appearance, and its body cavity contains plenty of germinal cells. For cercariae with an developed tegument, presence of the penetration glands is characteristic. Key words: Trichobilharzia regenti, germinal cells, mother...
17

Koordinační schopnosti žáků na 2. stupni základní školy / Coordination abilities of students of second grade elementary school

Číhalová, Tereza January 2017 (has links)
Name of thesis: Coordination abilities of students of second grade elementary school Author: Tereza Číhalová Tutor: PaedDr. Jana Hájková Department: department of physical education and sport Comparing the level of coordination abilities of children from sports classes and unsportsmanlike classes of second grade elementary school. Thesis in the theoretical part will deal with the motor abilities, the coordination abilities and ontogenesis. In the research part of the work will be focused on testing students' sports focused on athletics and unsportsmanlike classes of secondary school and post-processing and evaluation of results. Methodology: data collection, guided interview, comparison Conclusion: Finding a suitable test profile and preparing the necessary means for the measurement of target groups. Evaluation of results and processing them into charts and graphs. A group of athletes achieved better results than physically inactive students. Group of athletes achieved a slightly above-average overall results, the group of inactive students achieved a slightly below- average. Within a group, not a big difference between boys and girls. In tests, the best for both groups is Sprint according to a rhythm. In this test was the smallest difference in the results between the groups. The test, where was...
18

Mechanismy mateřské synchronizace fetálních cirkadiánních hodin / Mechanisms of maternal entrainment of the fetal circadian clock

Černá, Barbora January 2017 (has links)
Our body is influenced by many cyclical changes in the environment, such as day and night or seasons. To predict these changes and react to them in time, the organism is equipped with inner clock, which rhythmically influences many physiological processes, such as sleep or metabolic rhythms. Disrupting our inner rhythms at molecular and behavioral levels contributes to many serious disorders. It is necessary that all mechanisms of the inner circadian clock are developed and set up properly. Circadian clocks are set up by the mother, who passes rhythmical information about day and night cycle on to her embryo. Though a great attention is devoted to revealing the nature of this synchronization between the mother and her pup, the mechanisms of this process have not been fully understood yet. The aim of this thesis is to contribute to actual understanding of this synchronization. Experiments, performed in this thesis, relate to studying the ability of maternal signals to synchronize embryos with the environment. Feeding and light regime of pregnant rats was manipulated and the effect of these changes on the neuronal activity within the suprachiasmatic nuclei of 19-day embryos was analyzed.
19

Vývoj vojenského chování a jeho polyethismus u termitů / Ontogeny of soldier behaviour and its polyethism in termites

Homolka, Petr January 2015 (has links)
The presence of soldier caste is an important synapomorphy of group Isoptera. The adaptation of this caste to defense tasks is more than obvious and some of their morphological or even behavioral adaptations can be quite impressive. The polyethism in termites is relatively well known inbetween rather worker caste. If there are such a studies pointing at polyethism in soldiers, they are connected with soldier polymorphism. The morphological differences are of course important stimulus to role separation. The goal of this thesis was to examine the polyethism in the species of the termite with monomorphic soldiers - Prorhinotermes simplex. I did behavioral experiments with it in enclosed arenas, recorded on specific days. The data shows, that there are differences inbetween individuals and it would be benefical to invest further time to subsequent studies. The thesis bring out new point of view to defensive behaviour of termites and suggests, that even termite species without polymorphic species may have soldiers with different tasks. Besides I managed to map ontogeny of soldier behaviour in the first two weeks after moulting from presoldier instar. Key words: Isoptera, polyethism, soldiers, ontogeny, defensive behaviour Powered by TCPDF (www.tcpdf.org)
20

Ontogeneze vybraných taxonů trilobitů a agnostoidů ze středního kambria barrandienské oblasti / Ontogeny of selected taxa of middle Cambrian trilobites and agnostoids of the Barrandian area

Laibl, Lukáš January 2017 (has links)
This thesis deals with the ontogeny of trilobites and agnostids from the Cambrian of the Skryje-Týřovice and Příbram-Jince basins (Barrandian area, Bohemian Massif). Thesis is presented as a compilation of four papers that were published in scientific peer-reviewed journals. The introduction of the thesis serves as a general overview of the trilobite post- embryonic development and connects all published papers together. All four papers presented here are focussed on modern description of the post-embryonic development of Sao hirsuta, Ptychopariida sp. A, Ptychopariida sp. B, Ptychopariida sp. C, Ellipsocephalus hoffi, Ellipsocephalus polytomus, Hydrocephalus carens and Ecca- paradoxides pusillus. In addition, a discussion about the life-history strategies of early developmental trilobite stages is presented. It has been suggested that Sao hirsuta and Ptychopariida sp. A had benthic protaspides and that the early ontogenetic stages of Ptychopariida sp. B, Eccaparadoxides pusillus and Hydrocephalus carens were likely lecithortophic. Consequently, it has been documented that species with benthic protaspides show a strongly restricted geographic distribution and that lecithotrophic taxa seem to be associated with higher latitude areas. The developmental patterns of Ellipsocephalus hoffi and...

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