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Investigation of copper complexes using mass spectrometry
Yassaghi, Ghazaleh ; Roithová, Jana (advisor) ; Jaklová Dytrtová, Jana (referee) ; Polášek, Miroslav (referee)
This dissertation thesis reports the study of several copper complexes and their reactivity in the gas phase. The complexes were analyzed using different methods, namely, electrospray ionization-mass spectrometry (ESI-MS), infrared multiphoton dissociation (IRMPD) spectroscopy and theoretical calculations. In the first part, the complexes of redox-active ligands (catechol, maltol, and phenanthraquinone) with copper were studied under electrospray ionization conditions. [Cu(PQ)2]+ (PQ = 9,10-phenanthraquinone), [Cu(maltol)(maltol-H)]+ and [Cu(maltol)(maltol-H2)]+ were produced by electrospray ionization. The copper complexes were compared with complexes of other metals (Zn, Ag, and Na), and the structures were studied by collision induced dissociation (CID) and IRMPD spectroscopy. The redox process of copper complexes was studied using the C-O stretching mode as a redox marker and using fragmentation experiments. Both the phenanthraquinone and maltol ligands showed redox activity of the studied copper complexes in the gas phase. In the second part, negatively charged complexes of copper with pincer ligand L (L = N,N'-bis[2,6-diisopropylphenyl]-2,6-pyridinedicarboxamide) were investigated to show the effects of different counter-ions. The results showed that electrospray ionization of copper chlorate...
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The effect of meditation on cortisol levels in saliva
Kačerová, Kateřina ; Jaklová Dytrtová, Jana (advisor) ; Šteffl, Michal (referee)
Title: The effect of meditation on cortisol levels in saliva Objectives: The main objective of the research project in this master's thesis was to objectively (based on changes in cortisol levels) and subjectively (by method of questionnaire) study the effect meditation has on stress levels. Methods: The objective method in this work was measuring cortisol in saliva with the help of an established and certified ELISA method on an ELISA reader device. The cortisol level was measured before meditation and after meditation. A method of questionnaire was used to determine the subjective emotions and feelings of the participants before and after meditation. The total surveyed group consisted of 25 healthy men, students of UK FTVS with a valid medical exam, between the ages of 19 - 35. The experimental part and data collection were conducted in two phases. (i) First, it was determined, on ten of the same participants during two consecutive days, which type of meditation (static breathing or dynamic) will be better accepted by the participants and will have a greater effect on lowering cortisol levels. (ii) Then, static breathing meditation was selected (as more effective for the given group), whose effect on lowering cortisol levels was tested on a larger group of participants (15). Results: Cortisol...
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Separation of triazoles from real samples with capillary electrophoresis
Kovač, Ishak ; Jakl, M. ; Šolínová, Veronika ; Jaklová Dytrtová, Jana
The CE has become one of the advantageous tools in fungicides analysis in complex matrices due to its simplicity and separation efficiency. The separation of a group of thee triazole (i.e. penconazole, tebuconazole, and cyproconazole) fungicides was achieved with CD-MEKC with anionic Sg-CD as a selector at pH=4,8. The background electrolyte consisted of TRIS phosphate buffer (50 mmol/L) and 15 mmol/L SDS. The separation was performed on uncoated fused silica capillary with 500/425 mm (total/effective) length under -15 kV separation voltage. Achieved LOD values with this method were: 0,73, 1,88, 0,60, 1,18 (umol/L) for penconazole, tebuconazole, cyproconazole A and B respectively.
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Copper complexes with triazoles
Jaklová Dytrtová, Jana ; Jakl, M.
Triazoles are artificial chemicals used as fungicides as well as for pharmaceutical treatment. However, their reactivity is highly influenced by the presence of other chemicals. Especially, the presence of copper cations changes the reactivity of triazole by theoretically unexpected way. We have studied the interactions of the triazole ring with copper cations to help explain the reactivity of triazoles as a group.
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Tebuconazole and its behaviour in the presence of magnesium
Jakl, M. ; Jaklová Dytrtová, Jana
Tebuconazole is a fungicide frequently used in agriculture. Its possible impact to (non-)target species is influenced by its presence. Moreover, the presence of triazoles in soil has an impact to bioavailability of nutrients. This study brings the information potentially useful in the evaluation of tebuconazole fate in the environment. The studies based on the electrospray gas phase experiments provide an estimation of the tebuconazole ability to create complexes with magnesium.
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Method optimization for simultaneous separation of six triazole fungicides in HPLC
Kovač, Ishak ; Martín Miján, P. ; Del Sol Vega Alegre, M. ; Dejmková, H. ; Jaklová Dytrtová, Jana ; Schwarzová, K.
Triazole pesticides are widely used in agriculture against fungi pathogens. Their application is not restricted on just one member of the group, more importantly, the application is usually carried out in the mixture of two or more triazoles. Hence, this work focuses on simultaneous separation and detection of six triazole fungicides: penconazole, tebuconazole, propiconazole, cyproconazole, fenbuconazole, and difenoconazole. Two different columns were tested with different parameters for isocratic and gradient elution in HPLC with UV detector. On Purospher Reverse Phase-18 column with gradient elution isomers of triazoles cyproconazole and propiconazole were successfully separated. However, on this column, there was an overlap of some triazoles. In contrast, the isocratic elution on Kromasil Eternity-5-PhenylHexyl column showed sufficient separation capabilities. In further research, chiral separation of triazoles will be considered using capillary electrophoresis.
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Posterior chain muscle endurance and arm paddling peak power in amateur female surfers
Kopčilová, Michaela ; Jaklová Dytrtová, Jana (advisor) ; Prokešová, Eva (referee)
Title: Posterior chain muscle endurance and arm paddling peak power in amateur female surfers Objectives: Thesis is dedicated to female surfing, particularly paddling, as this is an undiscovered area of research. Very few studies have been carried out, which would focus on muscle activity in surfing. None of the studies focused on posterior chain or muscle activity of female surfers while paddling. Not only that the level of competitive surfing is increasing rapidly, as it will be part of Olympic Games in Tokyo in 2020, but the recreational surfers are also becoming more literate about surf science and willing to improve their surfing performance by dry land surf specific trainings. Surfing industry represents a worldwide business, where big companies offer sponsorship, which is reasonable motivation for young athletes (M. Mendez-Villanueva & Bishop, 2005). As the number of recreational and competitive female surfers is raising as well, the level of competitive female surfing is increasing (Booth, 2001) and professional female surfers are becoming equal in regards to getting the same amount of prize money in competitions, more research should be dedicated to female surfing. The aim of this thesis was to study association between posterior chain endurance and other variables such as frequency of...
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Voltammetric and Amperometric Determination of Nitrophenols Using Boron-Doped Diamond Film Electrode
Karaová, Jana ; Barek, Jiří (advisor) ; Šelešovská, Renáta (referee) ; Jaklová Dytrtová, Jana (referee)
Presented Ph.D. Thesis is focused on the use of the boron-doped diamond (BDD) electrodes for voltammetric and amperometric determination of selected nitrophenols: 2-nitrophenol (2NP), 4-nitrophenol (4NP), and 2,4-dinitrophenol (2,4DNP). These compounds are listed as "priority pollutants" by United States Environmental Protection Agency (US EPA) due to their negative impact on living organisms and are mainly used in agriculture as plant growth stimulators. BDD electrodes are used for determination of wide range of electrochemically both reducible and oxidisable organic compounds and have become a popular electrode material thanks to its commercial availability and excellent mechanical and electrochemical properties. A differential pulse voltammetric method was developed for the determination of 2NP, 4NP and 2,4DNP at a BDD film electrode using electrochemical reduction and of 4NP and 2,4DNP using electrochemical oxidation. The method was successfully applied for the direct determination of these compounds in drinking and river water in the concentration range from 4×10-7 to 2×10-5 mol.L-1 . To improve the limit of quantification, a preconcentration by solid phase extraction from 100 mL (drinking and river water) and 1000 mL (drinking water) of water samples was used with limit of determination...
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Penconazole and its behaviour in the presence of copper
Jakl, M. ; Jaklová Dytrtová, Jana
Penconazole is a fungicide frequently used in agriculture. Its possible impact to (non-)target species is influenced by its interactions e.g. with copper, typically present in soil as an ion (or in week complexes) or in bodies, as a part of enzymes. This study brings the information potentially useful in the evaluation of penconazole fate in the environment. The studies based on the electrospray gas phase experiments provide an estimate of the penconazole reactivity in copper presence including its possible degradation pathways.
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