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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.
141

Pojem evoluce a jeho vnímání u žáků základních a středních škol / Term of evolution and its understanding by students of secondary schools and high schools.

Müllerová, Lucie January 2012 (has links)
The term of evolution and its understanding by students of secondary schools and high schools This Master's thesis deals with the conception of evolutionary topic in schools and textbooks. It introduces education systems and curricular documents of England, Scotland and the Czech Republic. Based on this information an analysis of biology textbooks was made, which was focused on the theme of evolution. The research included 62 textbooks distributed by 27 different publishers. Comparative SWOT analysis of these textbooks has shown that the concept of biology in general is presented differently, what is also reflected in the interpretation of the studies of evolution. The questionnaire research based on those findings was done in the Czech Republic. It is focused on secondary school and high school pupil's knowledge and their personal opinions about this topic. 586 pupils took part in this research. It was found that in the context of evolutionary processes the pupils have problems to use commonly known biological, or evolutionary terms (e.g. adaptation, evolution of the organisms). On the other hand some pupils can easily define some more complicated evolutionary topics such as Neo-Darwinism. Pupils have quite various personal opinions on the issue of the evolution. Some of them are not interested in...
142

Studium a srovnávání hlavních typů evolučních algoritmů / Study and comparison of main kinds of evolutionary algorithms

Štefan, Martin January 2012 (has links)
Evolutionary algorithms belongs among the youngest and the most progressive methods of solving difficult optimization tasks. They received huge popularity mainly due to good experimental results in optimization, a simplicity of the implementation and a high modularity, which is an ability to be modified for different problems. Among the most frequently used Evolutionary algorithms belongs Genetic Algorithm, Differential Evolution and Evolutionary Strategy. It is able to apply these algorithms and theirs variants to both continuous, discrete and mixed optimization tasks. A subject of this theses is to compare three main types of algorithms on the catalyst optimization task with mixed variables, linear constraints and experimentally evaluated fitness function.
143

Evoluce genomu bakteriálních symbiontů vši \kur{Polyplax serrata} (Phthiraptera, Anoplura)

ŘÍHOVÁ, Jana January 2017 (has links)
Blood-sucking louse Polyplax serrata harbor two phylogenetically distinct symbiotic bacteria from the orders Legionellales (Gammaproteobacteria) and Neisseriales (Betaproteobacteria). Based on rigorous phylogenetic analyses, the first bacteria was confirmed as member of genus Legionella, and the name Candidatus Legionella polyplacis, sp. n. was proposed. Vertical transgeneration transmission was proved by visualisation of the symbiont in host tissues. Improved genome of latter symbiont is considerably larger and possesses more metabolic functions. In the genome, I found horizontally transferred operon, which encode synthesis of enzymes involved in urea cleavage.
144

Reverze pohlaví u ještěra s genotypově určeným pohlavím (Squamata: Acrodonta: Pogona vitticeps) / Sex reversion in the lizard with genotypic sex determination (Squamata: Acrodonta: Pogona vitticeps)

Ehl, Jan January 2015 (has links)
Sex determination among reptiles is a very variable matter across it's taxa. We meet there temperature sex determination and genotypic sex determination with many independent transitions between them. It is a group suitable to study evolution of sex determination, sex chromosomes and sex determination genes. Rare cases of sex reversal caused by extreme incubation temperature or exogenous hormones have been reported in recent years. In case of Acrodont lizard, Pogona vitticeps, was reported sex reversal caused by high incubation temperatures. Our purpose was to repeat the experiment, mainly due to insufficient conclusiveness of used methods. We wanted to expand the experiment by hormonal reversal, studying persistence of sex reversal to maturity and fertility of reversed individuals. We managed successfully to demonstrate sex reversal in both treatments by histological examination. Individuals with discordant phenotypic and genotypic sex were breed till one year of life, which demonstrate persistence of reversal. Our outcomes are concordant with most recent work on this species and show full functional phenomenon of sex reversal with reptiles, which studying could contribute to our understanding of evolution of sex determination.
145

Molekulární evoluce meiózy u diploidů a tetraploidů druhu Arabidopsis arenosa / Molecular evolution of meiosis in diploids and tetraploids of Arabidopsis arenosa

Holcová, Magdalena January 2017 (has links)
Meiosis is functionally conserved across eukaryotes, thus not expected to vary considerably among different species, and even less so among lineages within a species. However, recent studies showed that this is not necessarily the case in Arabidopsis arenosa. Genome scanning identified an excess differentiation in meiosis genes between A. arenosa diploids and tetraploids, interpreted as meiosis adaptation to the whole genome duplication in tetraploids and differentiation was also found between two diploid lineages. Thus, I present a population-based analysis of positive selection acting on meiosis proteins across multiple lineages of A. arenosa. I showed that meiosis proteins were under positive selection in all diploid lineages, mainly in the Pannonian and South-eastern Carpathian lineage. The evidence for positive selection in diploid lineages suggested differential pathways of meiosis adaptations in the species, probably reflecting the necessity to adapt to local environments, among all to temperature. The highest enrichment of amino acid substitutions (AASs) under positive selection was identified in tetraploids, in consistence with previous genome-scan results. As several interacting meiosis proteins were under positive selection in the same A. arenosa lineage, I hypothesize that the close...
146

Vývoj a dynamika palatální a faryngeální dentice u jesetera malého / Development and dynamics of the palatal and pharyngeal dentition in sterlet

Novotná, Štěpánka January 2021 (has links)
Dentition is a key vertebrate innovation showing not only great morphological diversity, but also different maintenance or replacement of functional teeth. Most extant vertebrates replace their dentition through addition of new teeth from deeply invaginated epithelium, i.e. the successional dental lamina, due to presence of dental stem cells. However, in some early branching lineages of ray-finned fishes (Actinopterygii), new tooth germs arise from the adjacent superficial epithelium without the presence of the successional dental lamina. Whether the two types of dental development in vertebrates are equivalent and whether comparable dental stem cells play role in tooth replacement is currently not satisfactorily evaluated. This Master thesis aims at describing the development of palatal and pharyngeal dentition of a member of an early branching lineage of ray-finned fishes, the sterlet sturgeon (Acipenser ruthenus). The sterlet dentition is fairly dynamic. The teeth are replaced without the successional dental lamina, however, this replacement shows characteristics similar to those described in vertebrates with the successional dental lamina. A marker of dental stem/progenitor cells, Sox2, is localized in the outer dental epithelium of the predecessor tooth in the vicinity of the adjacent taste...
147

Evoluční návrh využívající gramatickou evoluci / Evolutionary Design Using Grammatical Evolution

Repík, Tomáš January 2017 (has links)
p, li { white-space: pre-wrap; } Evoluce v přírodě slouží jako zdroj inspirace pro tuto práci . Základní myšlenkou je využití generativní síly gramatik v kombinaci s evolučním přístupem . Nabyté znalosti jsou aplikovány na hledání strategií chování v rozmanitých prostředích . Stromy chování jsou modelem , který bývá běžně použit na řízení rozhodování různých umělých inteligencí . Tato práce se zabývá hledáním stromů chování , které budou řídit jedince řešící nasledující dva problémy : upravenou verzi problému cesty koněm šachovnicí a hraní hry Pirátské kostky . Při hledání strategie hráče kostek , byla použita konkurenční koevoluce . Důvodem je obtížnost návrhu spravedlivé fitness funkce hodnotící výkony hráčů .
148

Využití SAT solverů v úloze optimalizace kombinačních obvodů / Application of SAT Solvers in Circuit Optimization Problem

Minařík, Vojtěch January 2019 (has links)
This thesis is focused on the task of application of SAT problem and it's modifications in area of evolution logic circuit development. This task is supposed to increase speed of evaluating candidate circuits by fitness function in cases where simulation usage fails. Usage of SAT and #SAT problems make evolution of complex circuits with high input number significantly faster. Implemented solution is based on #SAT problem. Two applications were implemented. They differ by the approach to checking outputs of circuit for wrong values. Time complexity of implemented algorithm depends on logical complexity of circuit, because it uses logical formulas and it's satisfiability to evaluate logic circuits.
149

Algoritmické obchodování na burze s využitím genetických algoritmů / Algorithmic Trading Using Genetic Algorithms

Červíček, Karel January 2019 (has links)
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Helvetica} Automatization is higly used in stock traiding. The thesis try to exploid optimalization principles and machine learning. Developed and tested stock traiding system proces financial time series and generate optimal strategy
150

Nové techniky návrhu celulárních automatů / New Cellular Automata Design Techniques

Baláž, Martin January 2013 (has links)
The aim of this master thesis is to introduce a new technique for the design of cellular automata which will provide a better possibilities for the implementation and solving given problems in an environment of non-uniform automata. In this work, the theoretical foundations of cellular automata have been summarized and the possibilities of their design were examined using two evolutionary principles that have commonly been used - genetic algorithm and cellular programming. Two principally different issues were selected on which the possibilities and capabilities of these techniques were proven: the synchronization problem and the system of implementation of logic gates in an environment of cellular automata. Based on a review of the implementation properties and the initial results of usage of these methods a new design method for cellular automata was created - cellular evolution. The cellular evolution with its method of "prediction of the future state of surrounding cells" provides new possibilities in the design of cellular automata since it operates with structured genes which allow the gene to be active for a variety of cellular surroundings. In the conclusion of this work, all three methods were compared on two selected problems and their abilities were summarized in a detailed overview.

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