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Application of CAD/CAM software for machining
Havran, Lukáš ; Jankových, Róbert (referee) ; Polzer, Aleš (advisor)
The aim of this bachelor thesis is the application of CAD / CAM system in machining. It contains a brief search of the possibilities of programming in CAD / CAM systems. Software that were used in this work were Creo Parametric from PTC and PowerMILL from Autodesk. The practical part of this work is focused on the production of a copy of a physically existing component using selected systems. In this part, attention is paid to the creation of a 3D model together with production of documentation using the Creo program and the creation of the machining program in PowerMILL for the implementation of production at CNC machine. The proposed procedure is verified by graphical simulation. Part of the practical part is also the selection of suitable machinery and tools for the actual production. The conclusion of the work is devoted to the control of the manufactured component.
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Application of CAD/CAM software for machining
Havran, Lukáš ; Jankových, Róbert (referee) ; Polzer, Aleš (advisor)
The aim of this bachelor thesis is the application of CAD / CAM system in machining. It contains a brief search of the possibilities of programming in CAD / CAM systems. Software that were used in this work were Creo Parametric from PTC and PowerMILL from Autodesk. The practical part of this work is focused on the production of a copy of a physically existing component using selected systems. In this part, attention is paid to the creation of a 3D model together with production of documentation using the Creo program and the creation of the machining program in PowerMILL for the implementation of production at CNC machine. The proposed procedure is verified by graphical simulation. Part of the practical part is also the selection of suitable machinery and tools for the actual production. The conclusion of the work is devoted to the control of the manufactured component.
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Study of redox reactions and adsorption of 4-nitrophenyl triazole labeled nucleosides and cresols on boron doped diamond electrodes for development of electroanalytical methods
Vosáhlová, Jana ; Schwarzová, Karolina (advisor) ; Havran, Luděk (referee) ; Navrátil, Tomáš (referee)
In this work, the application of boron-doped diamond electrodes with various surface pre- treatment were tested on selected oxidizable and reducible model compounds, specifically para and ortho cresols and 2'-deoxycytidine and 7-deazaadenosine labeled by 4-nitrophenyl triazole. The aim of the study was the investigation of electrochemical and adsorptive processes with respect to the development of electroanalytical methods of detection of the selected compounds, or utilization of boron-doped diamond electrodes as detectors in liquid-flow systems. Cresols were used as the model oxidizable compound. On O-terminated and polished boron- doped diamond electrodes, cresols provide oxidation signal owing to their oxidation to methylphenoxy radical at comparable potentials as on other carbon-based electrodes used as a reference in this work, i.e., glassy carbon electrode, pyrolytic graphite electrode, and carbon paste electrode. These carbon electrode materials show relatively high propensity to adsorption of reaction products, while such adsorption is minimal on boron-doped diamond. In situ anodic activation allows for a rapid regeneration of boron-doped diamond surface prior to each scan. A differential pulse voltammetric method that was developed with a detection limit of 0.61 mol∙l-1 to 2.97 mol∙l-1...
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Utilization of Catalytic Hydrogen Evolution in Electrochemical Analysis of Nucleic Acids
Fojta, Miroslav ; Daňhel, Aleš ; Špaček, Jan ; Havran, Luděk ; Šebest, Peter ; Orság, Petr ; Pivoňková, Hana ; Vosáhlová, J. ; Schwarzová-Pecková, K.
Catalysis of hydrogen evolution (CHE) at mercury in the presence of proteins was discoverd shortly after the introduction of polarography. In contrast, unmodified nucleic acids have not been reported to produce distinct signals due to the CHE to date. Chemically modified nucleic acids bearing certain extrinsic groups produce analytically useful signals due to hydrogen evloution catalyzed by the respective modifications. These species include (a) transition metal complexes, and (b) non-metal catalytically active organic moieties. In addition, the CHE has been reported to be invoved in guanine reduction process at the mercury-based electrodes.
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A Preliminary Study of Modification of 7-Deazaadenine with a Complex of Osmium Tetroxide with 2,2 '-Bipyridine
Vítová, Lada ; Havran, Luděk ; Fojta, Miroslav ; Šedo, O. ; Zdráhal, Z. ; Vespalec, Radim
Reactivity of a purine nucleic base analogue 7-deazaadenine (A*) in short oligodeoxynucleotide (ODN) towards an osmium tetroxide complex with 2,2'-bipyridine (Os, bipy) was investigated by means of electrochemistry, capillary electrophoresis and MALDI-TOF mass spectrometry. Electrochemical measurement, electrophoretic analyses and mass spectrometric analyses of reaction mixture proved that ODN with an A* residue yields an osmium adduct with properties similar to those exhibited by the well-known adduct of thymine.
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Primer Extension Reaction at the Gold Electrode Surface
Vidláková, Pavlína ; Havran, Luděk ; Fojta, Miroslav
One option of covalent DNA labeling is incorporation of chemically modified nucleotides using corresponding deoxynucleotide triphosphates into DNA molecules using polymerase-catalyzed primer extension. Primer extension is usually performed in solution and then the product is analyzed, often after a suitable separation. In our study we tested the possibility to prepare oligonucleotides with enzymatically incorporated anthraquinone labeled nucleotides using primer extension on templates immobilize at a gold electrode surface.
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Possibility of Using Purine Oxidation Signals for DNA Sequence Analysis
Špaček, Jan ; Cahová, Kateřina ; Havran, Luděk ; Fojta, Miroslav
Signals provided by electrochemical oxidation of single stranding DNA on the surface of pyrolytic graphite electrode, which correspond to the oxidation of adenine and guanine (A and G) are known for over forty years. The mechanism of oxidation of free A and G as well as nucleoside mono-, and triphosphates of these bases is know but the mechanism of oxidation of purines in the DNA still remains unexplained. Ratiometry of A and G signals could be a new tool for DNA sequence analysis, if signals of A and G oxidation obtained from single-stranded DNA adsorbed at the electrode surface are proportional to the number of oxidized As and Gs in studied samples. Our preliminary results suggest that there is a correlation, yet we encountered problems, which yet has to be addressed and explained before this method could be applied for DNA analysis.
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Examples of Using of Electrochemical Detection at Pencil Graphite Electrode with Enzymatic Labeling for Analysis of Nucleotide Sequence
Plucnara, Medard ; Haroniková, Lucia ; Špaček, Jan ; Havran, Luděk ; Horáková, Petra ; Pivoňková, Hana ; Ecsin, E. ; Erdem, A. ; Fojta, Miroslav
Many examples of utilization of enzymatic labeling for DNA sequence analysis has been described in literature so far. Some of them involve hybridization with complementary biotinylated probe, while others use incorporation of biotinylated nucleotides into DNA strand by DNA polymerases. Common approach is then binding of streptavidine-enzyme conjugates to biotin tags and incubation with substrate, which is converted to detectable product. Here, two recent applications using this principle are described for the detection of PCR amplicons and for SNP typing. Both techniques are combined with detection at pencil graphite electrodes.
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Natural and Synthetic Components of Nucleic Acids as Reactive Sites for DNA Modification by Osmium Tetroxide Complexes
Havran, Luděk ; Špaček, Jan ; Rozkosna, Jana ; Fojta, Miroslav
Natural DNA electroactivity find wide use in electrochemical analysis of its interactions and damage. For some applications is useful applied redox active tag to improve specificity of the analysis. One from utilized labels in this field are complexes of osmium tetroxide with nitrogen ligands (Os, L), which produce with DNA electroactive covalent adducts. Prime reaction site for Os, L is C=C double bond in pyrimidine nucleobases. If is 2,2'-bipyridine used as ligand, reaction is specific for single strand DNA. In this contribution will be presented results of electrochemical analysis of Os, bipy adducts with different ODN containing chemically modified purine bases.
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