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Digital processing of plant genomes
Jugas, Robin ; Škutková, Helena (referee) ; Sedlář, Karel (advisor)
This work continues in development of DNA numerical representation’s field in the recent years. The aim of this bachelor thesis is to work out an overview of numerical representations of DNA sequences and to describe the differences and properties of nuclear and mitochondrial genetic code focused on plants. Final objective is analysis of usability these signal’s representations for classification of organisms. The theoretical part is focused on description of biological facts, overview of conversion methods of DNA sequences into signals, the methods of organisms classification and the DTW algorithm. The practical part contain the created GUI application for organism classification based on numerical sequences and the analysis of usability these numerical representations for classification. The outputs of cluster analysis of numerical sequences are compared with the phylogenetic tree.
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Methods for fast sequence comparison and identification in metagenomic data
Kupková, Kristýna ; Škutková, Helena (referee) ; Sedlář, Karel (advisor)
Předmětem této práce je vytvoření metody sloužící k identifikaci organismů z metagenomických dat. Doposud k tomuto účelu spolehlivě dostačovaly metody založené na zarovnání sekvencí s referenční databází. Množství dat ovšem s rozvojem sekvenačních technik rapidně roste a tyto metody se tak stávají díky své výpočetní náročnosti nevhodnými. V této diplomové práci je popsán postup nové techniky, která umožňuje klasifikaci metagenomických dat bez nutnosti zarovnání. Metoda spočívá v převedení sekvenovaných úseků na genomické signály ve formě fázových reprezentací, ze kterých jsou následně extrahovány vektory příznaků. Těmito příznaky jsou tři Hjorthovy deskriptory. Ty jsou dále vystaveny metodě maximalizace věrohodnosti směsi Gaussovských rozložení, která umožňuje spolehlivé roztřídění fragmentů podle jejich příslušnosti k organismu.
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Character-based methods for DNA barcoding
Kalianková, Kateřina ; Sedlář, Karel (referee) ; Maděránková, Denisa (advisor)
This work deals with character-based DNA barcoding. DNA barcoding and character-based DNA barcoding methods are described in the introduction. Another part contains information of method CAOS (Characteristic Attributes Organization), method BLOG (Barcoding with LOGic) and method BLAST. Programs are described in the practical part. The end contains results.
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Numerical methods for classification of metagenomic data
Vaněčková, Tereza ; Sedlář, Karel (referee) ; Škutková, Helena (advisor)
This thesis deals with metagenomics and numerical methods for classification of metagenomic data. Review of alignment-free methods based on nucleotide word frequency is provided as they appear to be effective for processing of metagenomic sequence reads produced by next-generation sequencing technologies. To evaluate these methods, selected features based on k-mer analysis were tested on simulated dataset of metagenomic sequence reads. Then the data in original data space were enrolled for hierarchical clustering and PCA processed data were clustered by K-means algorithm. Analysis was performed for different lengths of nucleotide words and evaluated in terms of classification accuracy.
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Signal processing based methods for genome assembly refinement
Jugas, Robin ; Provazník, Ivo (referee) ; Sedlář, Karel (advisor)
The diploma thesis deals with sequencing methods and genome assembly methods including usage of numerical representations. The theoretical part of thesis describes the history of DNA research, generations of sequencing methods, the assembly methods themselves and definiton of numerical representations. Numerical represenatations serve to convert character form of DNA to numerical form and so allow to use digital signal processing methods. There is an algorithm for genome assembly using numerical represenatation proposed in thesis, which is later tested at sequence data.
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Bootstrap methods in phylogenetics
Sedlář, Karel ; Vohánka,, Jaroslav (referee) ; Škutková, Helena (advisor)
In recent decades, phylogenetic reconstruction has noted great development. It was achieved by using newly acquired molecular characteristics and processing that it began to be taken as an objective science. Rapid development showed that it is necessary to evaluate the results because new techniques provided phylograms from unreliable data. For these purposes, statistical sampling methods have been applied to the phylogeny, of which bootstrapping began later to dominate. However, it also has limitations, which should be considered during interpreting the results it provided to us. This work demonstrates by combining the principles of bootstrapping and consensus trees we can obtain phylograms with better properties than those of conventional phylograms.
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Character-based methods for DNA barcoding
Kalianková, Kateřina ; Sedlář, Karel (referee) ; Maděránková, Denisa (advisor)
This work deals with character-based DNA barcoding. DNA barcoding and character-based DNA barcoding methods are described in the introduction. Another part contains information of method CAOS (Characteristic Attributes Organization) and method BLOG (Barcoding with LOGic). Programs are described in the practical part. The end contains results.
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The use of genomic signal compression for classification and identification of organisms
Sedlář, Karel ; Vítek, Martin (referee) ; Škutková, Helena (advisor)
Modern classification of organisms is performed on molecular data. These methods rely on multiple alignment of sequences of characters which make them computationally demanding. Only small parts of genomes can be compared in reasonable time. In this paper, the novel algorithm based on conversion of the whole genome sequences to cumulative phase signals is presented. Dyadic wavelet transform is used for lossy compression of signals by redundant frequency bands elimination. Signal classification is then performed as a cluster analysis using Euclidian metrics where multiple alignment is replaced by dynamic time warping.
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