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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.
121

Sebemodifikující se programy v kartézském genetickém programování / Self-Modifying Programs in Cartesian Genetic Programming

Minařík, Miloš January 2010 (has links)
During the last years cartesian genetic programming proved to be a very perspective area of the evolutionary computing. However it has its limitations, which make its use in area of large and generic problems impossible. These limitations can be eliminated using the recent method allowing self-modification of programs in cartesian genetic programming. The purpose of this thesis is to review the development in this area done so far. Next objective is to design own solutions for solving various problems that are hardly solvable using the ordinary cartesian genetic programming. One of the problems to be considered is generating the terms of various Taylor series. Due to the fact that the solution to this problem requires generalisation, the goal is to prove that the self-modifying cartesian genetic programming scores better than classic one for this problem. Another discussed problem is using the self-modifying genetic programming for developing arbitrarily large sorting networks. In this case, the objective is to prove that self-modification brings new features to the cartesian genetic programming allowing the development of arbitrarily sized designs.
122

Evoluce karyotypů a určování pohlaví u leguánů (Squamata: Pleurodonta) / Evolution of karyotype and sex determination in iguanas (Squamata: Pleurodonta)

Altmanová, Marie January 2013 (has links)
Squamate reptiles in general possess an unusual variability in karyotype and sex determining mechanisms. However, in these two aspects, iguanas (Pleurodonts) are considered as a relatively conservative group of lizards. So far only genotypic sex determination with male heterogamety has been detected in this lineage. However, the sex chromosomes have not been revealed in many species by classical cytogenetics, probably due to their homomorphy. Significant variability in karyotype was observed only in the species-rich genera Anolis, Sceloporus and Liolaemus. The aim of this thesis was to investigate the genome of available species from the main iguanid lineages using classical and molecular cytogenetic methods. As well as finding the karyotype characteristics, which may represent synapomorphies of main iguanid lineages, the other aim was to try to identify sex chromosomes. This study confirmed previously published karyotypes of 13 species and established new descriptions of karyotype for eight species. The chromosomes of all studied specimens were examined by methods of classical and molecular cytogenetics, 21 species covering eight iguanid families were analysed in this thesis. The majority of studied species shared the apparently ancestral karyotype of the group, with diploid chromosome number...
123

Molekulárně-cytogenetická analýza adaptivní radiace gekonů rodu Paroedura (Squamata:Gekkota) / Molecular cztogenetic analysis of adaptive radiation in the gecko genus Paroedura (Squamata:Gekkota)

Koubová, Martina January 2013 (has links)
Paroedura genus includes 17 described species endemic to Madagascar and the Comoros Islands, where they went through a significant adaptive radiation. The genus Paroedura is monophyletic and well supported hypothesis on phylogenetic relationships among its species was published. Species vary considerably in body size and morphology and in preferences for habitat, some species live in sympatry. The genus Paroedura belongs to cytogenetically poorly studied family Gekkonidae which exhibits high variability in modes of sex determination and in comparison with basal gecko lineages, also considerable variability in the chromosome number and morphology. Karyotypes of only two species of the genus (P. picta, P. sp.) have been published. The aim of my thesis was to describe karyotypes of both sexes in all available species of the genus using conventional and molecular cytogenetic methods, to perform the phylogenetic analysis of karyotype evolution and chromosomal rearrangements in the genus, to assess the role of these rearrangements in the speciation of the genus and to detect sex chromosomes. I acquired karyotypes of both sexes in nine species representing the most of major phylogenetic lineages of the genus. According to the results, species can be divided into three groups according to diploid...
124

Mutační a substituční tempo u sexuálních a klonáních forem: možný klíč k vysvětlení persistence sexu u modelové skupiny sekavců? / Mutation and substitution rates in sexual and asexual forms: a clue to the persistence of sex in a model group of Cobitis?

Röslein, Jan January 2016 (has links)
TITLE: Mutation and substitution rates in sexual and asexual forms: a clue to the persistence of sex in a model group of Cobitis? AUTOR: Jan Röslein DEPARTMENT: Ústav živočišné fyziologie a genetiky AVČR, v.v.i. SUPERVISOR: Mgr. Karel Janko, Ph.D. ABSTRACT: Subject of this thesis is to test several hypotheses about the evolution of asexual reproduction in model group of fish family Cobitis and its mutual competition among sexual and asexual forms, which touches one of the oldest unresolved issues of biology. Specifically, the work deals with the accumulation of non-synonymous mutations, which accelerated accumulation in the genome of clonal lineages theoretically leads to increased extinction compared with sexually reproducing populations (so-called. The theory of Muller's ratchet and Kondrashov's hatchet). This thesis is based on a normalized cDNA sequencing data from oocytes and liver tissue, which has served as a base matrix (generated based on non-normalized cDNA data) for transcriptome sequencing (RNAseq). Consequently, the RNAseq data have served as validation for acquired polymorphisms, detection of differential expression of allele- specific expression (ASE) hybrid biotypes. This diploma thesis balances among the edges of vast spectrum of hypotheses regarding the evolution of the genus hybrid...
125

Usměrněná evoluce myšího polyomaviru / Directed evolution of mouse polyomavirus

Váňová, Jana January 2016 (has links)
The method of directed evolution represents a new approach to generate proteins with new or altered properties. The principle of directed evolution is random mutagenesis of the coding sequence for a protein of our interest followed by selection of generated mutants for the desired property. The aim of this pilot study was to investigate the possibility of utilization of directed evolution for alteration of mouse polyomavirus original tropism and virus retargeting to a model prostate cancer cell line. To generate randomly mutated gene encoding the major capsid protein of mouse polyomavirus, which is responsible for the interaction of the virus with cellular receptor for viral cell entry, error-prone PCR and DNA shuffling methods were used. Production of viruses composed of mutant major capsid protein was ensured by Cre/loxP site-specific recombination. The thesis also dealt with the design and characterization of the system for viral mutant selection. It was found that the prostate cancer cell lines markedly vary in their ability to bind and internalize particles derived from mouse polyomavirus. This knowledge can be used for the preparation of virus-like particles for prostate cancer diagnostics in the future. The study demonstrated that the method of directed evolution can be used for production...
126

Analýza tématu vznik a vývoj lidského druhu v učebnicích a pracovních sešitech pro ZŠ / Analysis of the topic Human Origin and Evolution in the Textbooks and the Workbooks for Elementary School

Hoffmannová, Valérie January 2020 (has links)
(AJ) The main aim of this diploma thesis is to analyze the learning tasks related to the topic of the origin and development of the human species in textbooks and workbooks for the second grade of primary school. Textbooks and workbooks of biology and history were selected for analysis. The learning tasks were categorized into individual categories of Tollinger taxonomy and Bloom's original taxonomy. The results of this classification were used to compare older and newer editions of selected textbooks and workbooks. I also found out the difficulty of tasks in each publications. This analysis revealed that teaching tasks from lower taxonomic categories (for both taxonomies), which do not high demands of cognitive operations, are more represented. Furthermore, this work deals how extent the topic in individual publications. Further analyzes revealed that teaching tasks of the origin and development of human species are more represented in the textbooks and workbooks of history. The results of this work could help teachers to find way in the offer of available textbooks and workbooks and help select a suitable publication to teach the topic of the origin and development of the human species. Key words: analysis, biology, Bloom's taxonomy, history, human evolution, Tollinger's taxonomy, textbooks, workbook
127

Karyotypová evoluce u vybraných čeledí entelegynních pavouků / Karyotype evolution of selected families of entelegyne spiders

Kotz, Matěj January 2020 (has links)
The Araneoidea superfamily is a diverse clade of spiders with a great species diversity. The whole superfamily displays considerable conservativeness of observed karyotypes. Most likely ancestral karyotype in males is 24 acrocentric chromosomes with X1X2 sex determination system. The goal of this study is to explore the karyotype diversity of two araneoid families - Araneidae and Mimetidae. The majority of studied species exhibit the ancestral karyotype. In some species of the aformentioned families was observed sudden increase in chromosome numbers, up to 2n♂ = 52 in Araneidae and up to 2n♂ = 57 in Mimetidae. The latter number is the highest chromosome count observed in Entelegynae so far. Increase in 2n goes hand in hand with increase in sex chromosome numbers, leading up to X1X2X3X40 system in Araneidae and up to X1X2X3X4X5X6X70 in Mimetidae. I suggest polyploidy as a possible mechanism of the increase. To test this hypothesis, I measured the size of the genome using flow cytometry and used fluorescence in situ hybridization for the detection of 18S rRNA and 5S rRNA genes. For one species, probe for U2 snRNA gene was also optimized as part of this thesis. In many species studied, these techniques were used for the first time ever. In the case of the family Mimetidae, the largest genomes in...
128

Modulace interakcí interleukinů a jejich receptorů / Modulation of interactions between interleukins and their receptors

Nepokojová, Tereza January 2020 (has links)
Scaffolds are proteins with high conformational stability, allowing us to implement multiple mutations into specific parts of the protein. Even with these mutations, the structural integrity of the protein is maintained as well as its physical-chemical properties. These mutations give the specific scaffold new properties. In most cases it is the binding specificity towards previously chosen target. The biggest advantages of scaffolds are their small size, stability, low-cost manufacturing, and easiness of preparation. Scaffold utilized in this thesis is unique for having two binging surfaces designed on which it can be mutated. Each of those two surfaces can be separately mutated to develop a binging site for two different proteins. In our case these mutations led to binding two nonidentical receptors of a human cytokine. Mutations are made with a use of yeast display, one of the methods of directed evolution. The main focus of this thesis is changing an expression system of the binding proteins from the yeast system to a bacterial one, their production and purification followed by characterization of those binding proteins using biophysical methods. These methods were used to evaluate structural and thermal stability, and binding affinity to both receptors of the beforementioned binding proteins....
129

Analýza vědomostí žáků základních a středních škol a interpretace evoluční biologie učiteli v České republice, Anglii a Skotsku / Analysis of Secondary School Pupils' Knowledge and the Interpretation of Evolutionary Biology by Teachers in the Czech Republic, England and Scotland

Hlaváčová, Lucie January 2016 (has links)
An evolution is considered the single greatest unifying theory in biology. Therefore, evolution is a crucial topic from the perspective of didactics of biology because it reaches contemporary paradigm of science education. These doctoral thesis deals with the educative aspects in the field of evolutionary biology. Given the fact that educational content and understanding of causal patterns in science may be influenced by the sociocultural background, the whole research is carried out in comparison with Great Britain. The main aim of the thesis is carried out three successive analyzes. First, the occurrence and the content of definitions of evolutionary terms in Czech and British science or biology textbooks have been compared (16 Czech and 16 British textbooks). Data were evaluated using content analysis and hierarchical cluster analysis. Subsequently, a comparison of teaching evolution has been made using a questionnaire survey (350 Czech and 122 British teachers) and interviews (10 Czech and 7 British teachers). Finally, a comparison of the Czech and British pupils' knowledge and opinions on specific evolutionary topics were obtained via a questionnaire (964 Czech and 97 British pupils). Statistically significant differences between Czech and British respondents were verified by Chi-square test...
130

Definice náboženství z hlediska sémiotiky Ch. S. Pierce / The definition of religion from the point of view of Ch. S. Pierce's Semiotics

Bromková, Petra January 2016 (has links)
The work is focused on delimiting the basic problematic of definition of religion in terms of Charles Sanders Peirce's semiotics. Its objective is througt selected Peirce's texts to interpret Peirce's philosophy of religion, which consists of concept of religion closely connected with Peirce's metaphysics, phaneroscopy, semiotics and agapism. It focuses primarily on Peirce's theory of evolution, the idea of God, the pragmatic way of inference through which one can come to the idea of God, and the relationship between religion and science. I conclude through the interpretation of Ch. S. Peirce's texts that the precise definition of religion can not be pursued in his theory. Even so, the semiotic conception of religion brings a new perspective: the religion could be based on the same principles that govern the science. It can also be understood as a community of people continually striving for truth. This community of people searches in its investigation for answers to the questions about theological ideals. The precondition of faith of individual members of religious communities is an experience of God, who is a perfect and the most general sign and together growth and semiosis in the universe, which people interpret. A believer comes to the worship of God through Musement, a special purposeless...

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