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Karyotypic evolution in eye-lid geckos (Squamata: Eublepharidae), a group with different modes of sex-determination
Pokorná, Martina
Chromosome rearrangements represent one of the most striking phenomena related to speciation. Nevertheless, their importance for other evolutionary processes is not well understood yet. Within some groups we observe even variability in the presence or absence of differentiated sex chromosomes. Such variability has a crucial role for our comprehension of general principles regarding the evolution of sex determining mechanisms. From this point, the family Eublepharidae is a very interesting model group as it includes species with both genetic sex determination and temperature-dependent sex determination. The investigation of the karyotype composition as well as of the structure and homology of sex chromosomes within such taxa could bring valuable information on the general evolutionary processes leading to the differentiation of karyotypes and sex chromosomes. In this work the description of karyotypes in several selected species of the family Eublapharidae was done by available cytogenetic techniques. I have examined following species: Coleonyx brevis, C. elegans, C. mitratus, C. variegatus, Eublepharis angramainyu, E. macularius, Goniurosaurus araneus, G. lichtenfelderi,G. luii, G. splendens, Hemitheconyx caudicinctus, Holodactylus africanus. It was found that the karyotypic differentiation among...
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Zařazení barevné pšenice Skorpion do krmné dávky brojlerů
Pokorná, Martina
The effect of the feeding of blue-coloured wheat Skorpion on the carcass performance and antioxidant activity of broiler chickens was studied. Crafted feed mixture was used to fed male chicken hybrid Ross 308. Before the start of the experiment we have divided the broiler chickens to a weight-balanced groups. Each week was weighting individual animals. All of the data, and the changes was recorded. At the end of experiment we reviewed influence of colored wheat on the parameters of broiler chickens, especially the mass increases, feed conversion and slaughter yield. As a control sample of wheat was elected common variety with red grains - Vánek. Feeding with Skorpion wheat has not been proven, in the statistical processing, any influence on additions, feed conversion and even slaughter yield. On the contrary, the assessment showed the improvement of antioxidant capacity of wheat variety Skorpion.
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Analysis of sex chromosomes and gene clusters in selected mygalomorph and araneomorph spiders
Pappová, Michaela ; Král, Jiří (advisor) ; Johnson Pokorná, Martina (referee)
1 Abstract: The diploma thesis focuses on study of sex chromosomes evolution and repetitive organized genes of chosen mygalomorph and araneomorph spiders. Spiders are characterized by complexicity of sex chromosome systems, their karyotypes contain multiple sex chromosomes X. Besides multiple X chromosomes they also contain a pair or two pairs of nondiferentiated sex chromosomes X and Y. The used methods include methods of classical cytogenetics (preparation of chromosome slides, C-banding) and methods of molecular cytogenetics (fluorescent in situ hybridization and comparative genome hybridization). Complex sex systems were discovered in the studied Theraphosidae spiders. In Theraphosidae spiders Atropothele socotrana and Poecilotheria vittata neo-sex chromosomes were found. Analysis of molecular differentiation of sex chromosomes suggests low differentiation of Y chromosome in neo-sex chromosomes and pair of nondifferentiated sex chromosomes XY. In haplogyne spider Kukulcania aff. hibernalis (X1X2Y), the Y chromosome was significantly differentiated, male specific signal covered the whole chromosome. Detection of 18S rDNA showed that karyotypes of majority of analysed Theraphosidae spiders and haplogyne spiders contain low number (1 or 2) of nucleolar organizing regions localized terminally, which...
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Probiotics for children's nutrition
Pokorná, Martina ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
This Diploma thesis deals with probiotic bacterias for children nutrition. It proposes a probiotic food supplement with a probiotic blend composed of a strain of the genus Lactobacillus and of the genus Bifidobacterium, which would be most suitable for infant consumers. The theoretical part is focused on probiotics, constitution of the children´s ganstrointestinal tract and screening of probiotic and gelatine supplements which are already sold on the market. In the experimental part, probiotic bacteria were subjected to model digestion, whereby mixtures of strains having the lowest reduction in viability after digestion were blend based on the results. The blend of Bifidobacterium breve CCM 7825T, Bifidobacterium longum CCM 4990 and Lactobacillus casei CCM 4798 was chosen as the most suitable blend of the lowest viability reduction. PCR in real time was demonstrated the presence of all strains added to the blend after model digestion. Finally, from the data was suggested a more comprehensive probiotic food supplement in the form of an alginate-agar gummy-bear for children over three years of age. The probiotic food supplement was subjected to sensory analysis too. The proposed probiotic food supplement also contained Chlorella and Spirulina active compounds and higher content of omega 3 and 6 fatty acids in hemp oil.
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Business process modeling in a context of customer communication
Pokorná, Martina ; Šisler, Vít (advisor) ; Slussareff, Michaela (referee)
(in English): The basis of this diploma thesis is to describe business process modelling and its current use in IT companies. The subject is to determine if respondents use process modelling in their companies or if they find it unsuitable. In the theoretical part, modelling in the context of information science, new media, and some models of communication are briefly presented. An important part of the theory is focused on the chapter of cognitive modelling, as a basic approach for creating process models. It follows an introduction of process modelling and a current market overview in this industry. The practical part maps the use of modelling in companies. Methodology is presented as first followed by data analysis. The research uses questionnaire survey for data collection, for qualitative data processing applies the grounded theory. Finally, the thesis evaluates the current state of modelling on the Czech market and defines the strengths and weaknesses of the process modelling.
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Comparison of the rate of evolution in genes located on reptile sex chromosomes and autosomes
Kuldanová, Kateřina ; Johnson Pokorná, Martina (advisor) ; Reifová, Radka (referee)
According to the "faster-X effect", X-linked genes and Z-linked genes evolve more quickly than autosomal genes. This theory is one of the currently intensively studied topics in evolutionary research. However, performing high quality tests is difficult because the results are influenced by several factors - the effective size of the population of the gonosome, sexual selection, the dependency of mutation rate and selection on sex, and the mechanism of dosage compensation. Conservation of genes and possible differences between rates of evolution of autosomes also play a role and not all studies take this fact into account. This study shows some of the difficulties of paired comparisons of dN/dS ratios traditionally used to test faster-X or faster-Z effects and introduces the basis of a new method of comparison of the rate of evolution (CREC) based on relative genetic distances between three species. The CREC method reduces the influence of conservation of genes on results and is more applicable for testing faster-X or faster Z effects in such species where two species without homologic gonosomes can be found for comparison. In means of the development of this method, the faster-Z effect was tested on a dataset of 9 autosomal and 13 Z-linked genes in the six-striped long-tailed lizard (Takydromus...
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Neo-sex chromosomes and their evolutionary significance
Košátko, Prokop ; Král, Jiří (advisor) ; Johnson Pokorná, Martina (referee)
Neo-sex chromosomes arise due to rearrangements between ancestral gonosomes and autosomes. Neo-sex chromosomes are valuable systems for the study of sex chromosome evolution. It is possible to use them for analysis of processes driving the formation of differentiated sex chromosomes, especially suppression of recombinations and alosome degeneration. The most important rearrangements forming neo-sex chromosomes are Robertsonian and reciprocal translocations. Speciation events are important consequences of birth of neo-sex chromosomes. The presented study is focused on the evolution of neo-sex chromosomes in drosophilids, muntjacs, and monotremes. Neo-sex chromosomes emerged in many Drosophila species. The genome of D. albomicans carries the youngest known neo-sex chromosome system, which arised only one hundred thousand years ago. Information from research into Drosophila neo-sex chromosomes underlines the importance of Muller's ratchet and background selection at the beginning of sex chromosome differentiation and hitchhiking and deleterious mutations at the end of this process. Genomes of muntjacs carry young and fast evolving neo-sex chromosomes. In several muntjac species, neo-sex chromosomes form a considerable part of the genome. The neo-sex chromosome systems of monotremes consist of many...
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Use of cytogenetical methods in taxonomy of Arachnida (Arachnida)
Alaverdyan, Argam ; Šťáhlavský, František (advisor) ; Johnson Pokorná, Martina (referee)
This bachelor thesis deals with the use of cytogenetic methods in taxonomy of Arachnida. To understand this matter, we need to analyse available information about inter and intraspecific karyotype variability of individual orders. At the beginning of the thesis there is a description of cytogenetic methods used with Arachnida.They are used to gather the karyotype's fundamental information, such as the diploid number of chromosomes, chromosome morfology and possible occurence of sex chromosomes. Main part of the thesis is focused on describing karyotypes of selected orders (Amblypygi, Palpigradi, Pseudoscorpiones, Scorpions, Opiliones and Araneae) and considering the convenience of use of cytogenetic methods for their taxonomy based on these information. The thesis includes current number of described genera (species) of the orders, as well as a number of cytogenetically analyzed genera (species) for comparison.
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