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Crystallization kinetics of PP impact copolymers
Krajčik, Ladislav ; Poláček, Petr (referee) ; Bálková, Radka (advisor)
In this bachelor thesis, the kinetics of crystallization was studied for three PP copolymers with ethylene-propylene rubber after multiple extrusion. The crystallization rate was determined from the diameter growth of spherulites with time. The growth was observed in-situ by polarizing optical microscope (POM). Isothermal melt-crystallization was investigated at three temperatures (135, 140 and 150 °C). The crystallization rate decreased with temperature for all samples and varied among particular samples the most likely due to the different structure (different polymerization technology). The third extrusion has not affected the crystallization rate compared with the first one. The ? and ß structure of PP was distinguished with help of the first order retardation plate together with determination of the types of spherulites. The lamellar thickening near the border of melt was observed for all samples that crystallized at 135 °C for a long time.
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Genetická a morfologická variabilita skupiny \kur{Melampyrum nemorosum}
DRAHNÍK, Petr
Melampyrum nemorosum agg. is very complicated group of hemiparasitic plants. According to the traditional concept, 15 species is distinguished. Recent molecular analyses show a need of critical taxonomic revision of group and a potential importance of ancient hybridization. Analysis of 3 regions of cpDNA (trnTUGU-trnLUAA, psbA-trnHGUG, rpl32-trnLUAG) and 2 regions of nuclear DNA (Agt1 and At103) reveals well supported lineage with limited geographical distribution. Morphology and genome size of genetically supported lineages were compared.
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Genetická a morfologická variabilita skupiny \kur{Melampyrum nemorosum}
DRAHNÍK, Petr
Melampyrum nemorosum agg. is very complicated group of hemiparasitic plants. According to the traditional concept, 15 species is distinguished. Recent molecular analyses show a need of critical taxonomic revision of group and a potential importance of ancient hybridization. Analysis of 3 regions of cpDNA (trnTUGU-trnLUAA, psbA-trnHGUG, rpl32-trnLUAG) and 2 regions of nuclear DNA (Agt1 and At103) reveals well supported lineage with limited geographical distribution. Morphology and genome size of genetically supported lineages were compared.
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Variability of Ephemeroptera of family Baetidae (Insecta, Ephemeroptera, Baetidae)
KOLLROSS, Jan
This thesis deals with a variability of the Baetis fuscatus species-group (Ephemeroptera: Baetidae). This study contains three main topics: The first one is distinguishing between two highly similar species, Baetis scambus and Baetis fuscatus based on morfological structures, specifically their mouthparts - labial palps. To analyze the shape of the labial palps, I applied a computerized outline analysis. Second topic is focused on the validity of Baetis beskidensis as a distinct species based on the morphology and DNA sequences (obtained for the topotypical material for the first time). And finally, I also investigated some samples from Corsica in attempt to discover new species of the Baetis fuscatus species-group. I found that most probably it is not possible to distinguish between Baetis scambus and Baetis fuscatus based on the shape of their labial palps. Baetis beskidensis is morfologically different, but genetically not distinctly separated from other representatives of the Baetis fuscatus species-group. I didn´t discover any distinct morphological differences in specimens from Corsica, pointing to the possible existence of new species.
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Pragmatic lemmatizer of Czech language
Vacek, Matěj ; Strossa, Petr (advisor) ; Kliegr, Tomáš (referee)
This thesis is focused on lemmatizing of nouns and adjectives. It is based on morphology of Czech language. The goal is to create a lemmatizer which can stem words with success rate 90% (at least). At the same time the lemmatizer should be very easy, it should consist as little rules as possible. Lemmatizer will be created to work with real estate adverts, especially houses for sale. In this thesis there will be made an analysis of specific characters of this area. Lemmatizer will be created according to results of this analysis. Lemmatizer was written in Java. Only three types of rules were used and generally the lemmatizer created correct stems in 96.4% of all words.
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Differences in lymphocyte morfology of children and adults
ZMEŠKALOVÁ, Dagmar
Lymphocytes belong among white blood cells and they are involved in the body defense reactions. With other cells they create the human immunity system. In blood counts they are included in the differential leukocyte budget. Morphology of lymphocytes is evaluated in the microscope. The evaluation of morphology is an important aspect in distinguishing a normal state from a state that is caused by infection or hematological diagnosis. In this dissertation I will be dealing with the percentage of lymphocytes in the peripheral blood from birth to adulthood, measuring cell size and morphology evaluation of four types of cells: normal lymphocytes, atypical small lymphocytes which resemble "hematogones" , atypical large reactive lymphocytes with nucleus changes and esp. in the cytoplasm and and large granular lymphocytes (ie. LGL). On each lymphocyte I also used special staining for visualisation of the nucleoli for evaluation of three types of them - ringed, large and micronucleoli and number of nucleoli in cells. The purpose of this work is a microscopic comparison of the number of lymphocytes, their size, type and type of nucleus as it varies depending at the age from birth to adulthood.
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The morphology of penis and baculum in selected genera of African rodents
HORÁKOVÁ, Sylvie
This master thesis consists of two main parts. The first of them represents a compilation of information and facts about baculum, specifically about its presence, function and evolution in mammals. Further I focused on biological characters of five genera of African muroid rodents (Acomys, Aethomys, Gerbilliscus, Saccostomus, Stenocephalemys), which were analyzed in detail in the second part of my thesis in respect of their penial and bacular morphology.
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Czech as a foreign language. Modified linguistic description of the selected grammatical categories of Czech
KUTLÁKOVÁ, Michala
The goal of this dissertation is to propose and develop theoretical linguistic basis for the branch of Czech as a foreign language. Specifically, it deals with the complex linguistic description of Czech grammar in the function of a foreign language, which would introduce a theoretical solution for the processing of didactic grammars of Czech for foreigners. This description is supposed to provide such a range of linguistic information, which depending on the purpose, enables the variable processing of language structures and simultaneously clarifying the relationships and connections between them. Above mentioned linguistic description of Czech as a foreign language is focused on a specific group of non-native speakers, in our case, a group of non-native speakers, whose mother tongue is German. As it is a model process of description in this dissertation, the attention is only paid to the selected grammatical categories of Czech, namely the grammatical category of the genitive of substantives and verbal aspect. The issue of the description of the grammar of a natural language is initially discussed in general terms, in the part where we define the types of grammars that are relevant to our work. Subsequently we characterize both languages, i.e. Czech and German, in the terms of their differentiation, stratification and typological point of view. The particular linguistic description and its model application, which is the core of this work, is called a modified linguistic description with the reference to Dolník J. (1993). This description is based on five sources. These are the theoretical works of leading Czech and Slovak linguists, dealing with the issue of natural language and works describing Czech grammar. Further starting points for the proposed comprehensive description of Czech grammar is to define particular reference levels according to SERR for Czech as a foreign language, a research unit focused on the target group of non-native speakers and their perception of the difficulties of Czech grammatical phenomena, and last but not least, the research probe carried out in the particular corpora of the Czech National Corpus.
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Polyphasic approach to the taxonomy of selected cyanobacteria
MAREŠ, Jan
The modern taxonomic revision of cyanobacteria is a work in progress, with both theoretical and practical challenges to be addressed. This thesis investigated selected terrestrial cyanobacterial taxa using a polyphasic approach, based on molecular phylogenetic analysis and accompanied by phenotypic characterization and nomenclatural treatment. Diverse methodological approaches were used including optical and transmission electron microscopy, molecular analysis (DNA sequencing) of cyanobacterial strains, single cells and filaments, and phylogenetic analysis of multiple genomic loci. This study provided systematic revisions of individual cyanobacterial genera and the entire phylum, and suggestions for future study projects.
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