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Use of capillary electrophoresis with UV photometric and electrospray ionization mass spectrometric detection for the study of interaction of compounds
Konášová, Renáta ; Jaklová Dytrtová, Jana (advisor) ; Mikšík, Ivan (referee) ; Tůma, Petr (referee)
Capillary electrophoresis (CE) is highly efficient separation method based on the different migration velocity of ions in liquid media in electric field. It is commonly used in analytical laboratories and due to the different separation principle it is applied as a complementary method to the chromatographic methods (HPLC and UHPLC). Beside the applicability of CE for quantitative/qualitative analysis, the method can be used also for physico-chemical characterization of compounds (e.g. determination of acid dissociation constants of weak electrolytes or stability constants of complexes). This work is focused on the applicability of CE methods for determination of physico- chemical characteristic of compounds (acid dissociation constants of triazole fungicides and stability constants of dibenzo-18-crown-6, benzo-18-crown-6 and 18-crown-6 ether complexes with metal ions in hydro-organic solvent mixtures) and on the possibility to use affinity CE (ACE) with electrospray ionization-mass spectrometric detection (ACE- ESI/MS) for the study of non-covalent interactions of compounds. For the online hyphenation of CE and ESI/MS, two highly sensitive CE-ESI/MS interfaces were tested: i) porous tip and ii) nano-sheath liquid flow. The ability of the CE-ESI/MS interfaces to effectively decouple spray and...
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Analysis of biologically active compounds using high performance separation methods
Adamusová, Hana ; Bosáková, Zuzana (advisor) ; Jelínek, Ivan (referee) ; Tůma, Petr (referee)
In the first part of this doctoral thesis, a new analytical HPLC-MS/MS method for monitoring of concentration changes of 17β-estradiol (βE2) during in vitro mouse sperm capacitation was developed. Capacitation was performed for three initial concentrations of βE2 (200, 20 and 2 μg/L). For all the concentrations a similar trend for the total unbound βE2 was observed. In general, the βE2 concentration decreased to reach its minimum and then increased again. The position of the minimum differed for the individual tested βE2 concentrations. Experimentally obtained results were subjected to the kinetic analysis. The curves fitted through the experimentally determined points displayed an autocatalytic character. For the agreement between the curves obtained by fitting through the experimental points and the theoretical calculated curves, it is necessary to assume that the first step is adsorption of βE2 onto the surface of the sperm controlled by Langmuir isotherm. The kinetic study was also used to study the effects of fluorides and aluminium fluoride complexes on the capacitation of mouse sperm. The experimental points were in very good agreement with the shape of the theoretical curves and this fact verifies the mechanism of the mouse sperm capacitation kinetics. In the second part of this work, two...
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Cloud database for soil information
Andreeva, Olga ; Nečaský, Martin (advisor) ; Tůma, Petr (referee)
Title: Cloud database for soil information Author: Olga Andreeva Department: Department of Software Engineering Supervisor: doc. Mgr. Martin Nečaský, Ph.D., Department of Software Engi- neering Abstract: The mere presence of scientific data is not enough. Reliable storage and ease of publication critically contribute to the data's usefulness. The Africa Soil Information Service's mission is to describe and understand Africa's soil and landscape resources. To ensure its accomplishment the introduc- tion of modern information technologies is essential - they provide the necessary means to safely store, easily share and analyse the information collected from soil samples and drone imagery. In the presented work we develop a system that will tackle one part of the problem - how to store the information extracted from soil samples. The current method that is employed by scientists consists of making a record on paper by hand in one of the books in the laboratory's storage room. Such system, of course, does not allow to easily share the data, it is prone to damages (e.g. in case of _re) and leaves little room for analysis (especially using methods from machine learning, which require a large set of digital data). By contrast our system, developed in the form of a web application, stores soil information in the...
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Application of Mass Spectrometry for Analysis of Biologically Active and Clinically Significant Compounds.
Štícha, Martin ; Jelínek, Ivan (advisor) ; Smrček, Stanislav (referee) ; Tůma, Petr (referee)
- 8 - ABSTRACT (EN) The thesis is submitted as a commented set of reviewed publications documenting and depicting the possibilities of mass spectrometry in the field of chemical, biological and pharmaceutical research; namely for the purposes of structure elucidation of selected organometallic complexes, analyses of drugs and their metabolites, monitoring of important biological markers. In course of experimental work, the following objectives were studied and solved: Proposal and realization of micro-scale preparation of selected rhenium complexes with aromatic ligands, utilizing tetrabutyammonium tetrachlorooxorhenate as a starting material; preparation and structure characterization of oxorhenium(V) complexes with 1,2-dihydroxybenzene, 1,2,3-trihydroxybenzene, and 2,3- dihydroxynaphtalene as ligands by means of ESI/MS, APPI/MS and LDI-MS; ESI/MS and UV/Vis study of kinetic behavior of complexes arising from the reaction of tetrabutylamonnium tetrachlooxorhenate with pyrogallol and catechol as ligands. Special aim was devoted to the study of subsequent chemical transformation of primarily formed Re(V) complexes; structure characterization of selected ferrocene complexes with copper, gold and silver by means of ESI/MS. Proposal of methodology of structure characterization and quantification of the...
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Analysis of vernix caseosa lipids by chromatografic methods and mass spectrometry
Míková, Radka ; Cvačka, Josef (advisor) ; Jelínek, Ivan (referee) ; Tůma, Petr (referee)
(EN) Vernix caseosa is a white creamy substance that covers the skin of a newborn. It is produced during the third trimester by the skin of the baby and remains there until the age of one or even two weeks. It is uniquely human. In utero, vernix protects the skin from maceration, during the birth it serves as a lubricant and after the delivery it protects the baby against infection and regulates the temperature. As vernix is produced in third trimester, prematurely born infants lack it and this may lead to, among other things, suffering from desiccation and therefore heat loss. It is important to study it thoroughly and to find a suitable substitute of vernix for the preterm infants. Vernix consists of lipids, proteins and 80 % water. This project is aimed at the lipids. Vernix is composed of 10 % of lipids. Basic analytical methods of pocessing vernix were searched. The methods of isolation, separation and transesterification have been optimized for the lipids. For separation, thin-layer chromatography has been chosen. The method of the lipid analysis of intact molecules by MALDI-TOF MS has been optimized for these lipids. The results were confirmed using fragmentation spectra and transesterification. Esterified lipids were measured by gas chromatography coupled with mass spectrometry detection....
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Use of liquid chromatography in pharmaceutical analysis and preparation of monolithic stationary phases for thin-layer chromatography
Vojta, Jiří ; Coufal, Pavel (advisor) ; Tůma, Petr (referee) ; Jelínek, Ivan (referee)
(EN) In the first part of this work, analytical methods for determination of impurities of active pharmaceutical ingredients (API) in combined pharmaceutical dosage forms were developed and validated. Development of the methods covered both the optimization of sample preparation procedure and chromatographic conditions. The methods were validated according to International Conference on Harmonization guideline and both of them were confirmed to be able to analyze stability samples. Impurities in paracetamol, codeine phosphate hemihydrate and pitophenone hydrochloride in the presence of fourth API fenpiverinium bromide were separated by using ion-pair reversed phase chromatography with gradient elution. Symmetry C18, 250 x 4,6 mm, 5 µm heated to 35 řC was used as a separation column. A diode array detector was used. The detection wavelengths were set as follows: 220 nm for paracetamol impurity K, 245 nm for paracetamol and its other impurities and 285 nm for codeine, pitophenone and their impurities. Impurities in valsartan, amlodipine besylate and hydrochlorothiazide were separated by reversed phase UHPLC method with gradient elution. Chromatographic column Zorbax Eclipse C8 RRHD, 100 x 3,0 mm, 1,8 µm heated to 30 řC and spectrophotometric detection were used. The detection wavelengths were set as...
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Application of Software Components in Operating System Design
Děcký, Martin ; Tůma, Petr (advisor) ; Döbel, Björn (referee) ; Sojka, Michal (referee)
This thesis describes the primary goal of the HelenOS microkernel multiserver operating system. The primary goal of the HelenOS project is to create a comprehensive research and development platform in the domain of general-purpose operating systems that would support state-of-the-art approaches and methods (such as verification of correctness) while at the same time focusing on practical relevance. The text of the thesis describes what specific means in terms of design (based on software components), implementation, development process and verification are used to achieve the primary goal. The thesis also evaluates the current state of HelenOS. Powered by TCPDF (www.tcpdf.org)
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Run-time performance testing in Java
Kotrč, Jaroslav ; Horký, Vojtěch (advisor) ; Tůma, Petr (referee)
This work focuses on relative comparisons of individual method's performance. It is based on Stochastic Performance Logic, which allows to express, for example, that one method runs at most two times longer than another method. These results are more portable than absolute values. It extends standard unit tests with performance assumptions, which are evaluated during actual run-time of a released application. Dynamically added and removed instrumentation is used for automatic modification of the production code. Instrumentation part uses DiSL framework to be able to seamlessly measure even Java system classes. Methods are measured sequentially, the number of concurrently measured methods is dynamically changed and the measurement code is removed as soon as required data are obtained. The results show that this approach may bring appreciably lower overhead peaks than measuring all methods at once. The prototype was compared with JMH tool and the results show that it is able to accurately measure methods running longer than 1 ms. Powered by TCPDF (www.tcpdf.org)
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Garbage Collection in Software Performance Engineering
Libič, Peter ; Tůma, Petr (advisor) ; Murphy, John (referee) ; Noorshams, Qais (referee)
Title Garbage Collection in Software Performance Engineering Author Peter Libič peter.libic@d3s.mff.cuni.cz Advisor doc. Ing. Petr Tůma, Dr. petr.tuma@d3s.mff.cuni.cz Department Department of Distributed and Dependable Systems Faculty of Mathematics and Physics Charles University Malostranské nám. 25, 118 00 Prague, Czech Republic Abstract The increasing popularity of languages with automatic memory management makes the garbage collector (GC) performance key to effective application execution. Unfortunately, performance behavior of contemporary GC is not well understood by the application developers and often ignored by the per- formance model designers. In this thesis, we (1) evaluate nature of GC overhead with respect to its effect on accuracy of performance models. We assess the possibility to model GC overhead as a black-box and identify workload characteristics that contribute to GC performance. Then we (2) design an analytical model of one-generation collector and a simulation model of both one-generation and two-generation collectors. These models rely on application characteristics. We evaluate the accuracy of such models and perform an analysis of their sensitivity to the inputs. Using the model we expose the gap between under- standing the GC overhead based on knowing the algorithm...
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HelenOS VFS-FUSE connector
Bouška, Zdeněk ; Děcký, Martin (advisor) ; Tůma, Petr (referee)
This master thesis deals with the implementation of a connector between FUSE file system drivers and HelenOS native VFS interface. The thesis first describes the way of finding the best solution and the potential possibilities. The low level layer solution is described as the best one. Further the thesis describes the real implementation of the connector. As the implementation of the connector was successful the thesis then describes in detail the parts of the fully functional solution in real-life HelenOS system. With this solution in place almost no changes are necessary to be done neither in FUSE nor in Helenos VFS. The connector implementation is demonstrated on two real-life FUSE file systems exFAT and NTFS which were ported to HelenOS. Powered by TCPDF (www.tcpdf.org)
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