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Synthesis and Characterization of Arylspiroborates
Sedláčková, Simona ; Jelínek, Ivan (advisor) ; Sobotníková, Jana (referee)
Arylspiroborates have some very interesting properties, which include biological activities and the potential anti-tumor activities. The aim of the thesis was to prepare some complexes using mainly phenolic ligands (catchol, pyrogallol, 3-methoxycatechol, 2,3-dihydroxynaphthalene and 4tertButylcatechol) and their detailed characterization using ESI-QqTOF. With some of these prepared complexes collision experiments were performed and based on the results, the fragmentation mechanisms for these substances were proposed.
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Anthocyanins in plant leaves: protective function and spectroscopic detection
Nikodymová, Michaela ; Albrechtová, Jana (advisor) ; Urban, Otmar (referee)
Plants have to cope with the change in the various environmental factors, the change of these factors means stress for plants. Stress factors can cause damage that lead to inhibition of growth and photosynthesis, resulting in the extreme cases in the death of the whole organism and negatively affect farm yields. Plants have to develop defensive mechanisms, including the accumulation of anthocyanins in leaves. The aim of the present review is to summarize the knowledge about the influence of stress factors on the accumulation of anthocyanins in leaves and about the function of anthocyanins in the protection. Anthocyanins most often act as antioxidants that react with ROS and inactivate them, they can also act as filters against UV radiation and as a protection against herbivores. Further, there are summarized the knowledge about spectral methods of detection of anthocyanins in leaves with emphasis on non-destructive detection methods. Spectral methods allow the analysis of anthocyanins based on the interaction of the leaf and its chemical components with the incident radiation. The most commonly used method is UV-VIS spectrophotometry. In order to study pigment change in leaves during ontogenetic development, non-destructive methods of pigment detection should be used. Suitable method can allow us...
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NMR study of solution dynamics of LnIII complexes of monophosphorus H4dota analogues
Svítok, Adam ; Hermann, Petr (advisor) ; Dračínský, Martin (referee)
Lanthanides have several specific properties which cannot be found for other elements in the periodic table. Among various applications of lanthanides, complexes of LnIII ions are used in medicine, e.g., as contrast agents in MRI, as luminescent probes or as radiopharmaceuticals, where their specific properties are important. These complexes must be kinetically inert to prevent release of highly toxic "free" LnIII ions. This requirement is fulfilled with pre-organized ligands such as analogues of H4dota (1,4,7,10- tetraazacyclododecane-1,4,7,10-tetraacetic acid). Many of important properties of LnIII complexes of H4dota, such as relaxivity, isomerism and fluxionality, depend on the solution dynamics of the complexes. However, the knowledge of this solution dynamics is limited for LnIII complexes of H4dota derivatives with phosphonate or phosphinate pendant arms. Recently, a new dynamical process where phosphonate oxygen atoms interchange through a bidentate phosphonate intermediate ("a phosphonate rotation") has been proposed by DFT calculations but unconfirmed experimentally. To prove the process experimentally, solution dynamics of LnIII complexes of monophosphonate and monophosphinate derivatives of H4dota was investigated. Especially, to examine the "P-rotation", 17 O NMR spectroscopy was used...
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Synthesis and Characterization of Arylspiroborates
Sedláčková, Simona ; Jelínek, Ivan (advisor) ; Sobotníková, Jana (referee)
Arylspiroborates have some very interesting properties, which include biological activities and the potential anti-tumor activities. The aim of the thesis was to prepare some complexes using mainly phenolic ligands (catchol, pyrogallol, 3-methoxycatechol, 2,3-dihydroxynaphthalene and 4tertButylcatechol) and their detailed characterization using ESI-QqTOF. With some of these prepared complexes collision experiments were performed and based on the results, the fragmentation mechanisms for these substances were proposed.
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Anthocyanins in plant leaves: protective function and spectroscopic detection
Nikodymová, Michaela ; Albrechtová, Jana (advisor) ; Urban, Otmar (referee)
Plants have to cope with the change in the various environmental factors, the change of these factors means stress for plants. Stress factors can cause damage that lead to inhibition of growth and photosynthesis, resulting in the extreme cases in the death of the whole organism and negatively affect farm yields. Plants have to develop defensive mechanisms, including the accumulation of anthocyanins in leaves. The aim of the present review is to summarize the knowledge about the influence of stress factors on the accumulation of anthocyanins in leaves and about the function of anthocyanins in the protection. Anthocyanins most often act as antioxidants that react with ROS and inactivate them, they can also act as filters against UV radiation and as a protection against herbivores. Further, there are summarized the knowledge about spectral methods of detection of anthocyanins in leaves with emphasis on non-destructive detection methods. Spectral methods allow the analysis of anthocyanins based on the interaction of the leaf and its chemical components with the incident radiation. The most commonly used method is UV-VIS spectrophotometry. In order to study pigment change in leaves during ontogenetic development, non-destructive methods of pigment detection should be used. Suitable method can allow us...
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Applications of modern spectral tools in financial econometrics
Křehlík, Tomáš ; Baruník, Jozef (advisor) ; Hanousek, Jan (referee) ; Croux, Christopher (referee) ; Wang, Yao (referee)
Spectral tools in econometrics have lately experienced a renewed surge in interest. This dissertation contributes to this literature by providing conceptually different spectral-based methods and their applications to problems of modern economics. In the first part, we take a spectral decomposition of realized volatility and construct a multivariate GARCH style model that we fit by standard quasi-maximum likelihood and generalized autoregressive score procedures. We build our model on a belief that market agents obtain information in various time horizons and therefore form their expectations in various informational horizons. This behavior creates an overall volatility process that is a mixture of spectrum specific processes. We then apply the model to the currency markets, namely GBP, CHF, and EUR. With the help of the model confidence set test we show that the multi-scale model and the generalized autoregressive score based models produce forecasts that are in most cases superior to the competing models. Moreover, we find that most of the information for future volatility comes from the high frequency part of the spectra representing the very short investment horizons. In the second part, we provide a spectral decomposition of a system multivariate connectedness measure based on Diebold and Yilmaz...
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Stochastic equations and numerical solution of pricing option model
Janečka, Adam ; Jablonský, Josef (advisor) ; Pelikán, Jan (referee)
In the present work, we study the topic of stochastic differential equations, their numerical solution and solution of models for pricing of options which follow from stochastic differential equations using the Itô calculus. We present several numerical methods for solving stochastic differential equations. These methods are then implemented in MATLAB and we investigate their properties, especially their convergence characteristics. Furthermore, we formulate two models for pricing of European call options. We solve these models using a variant of the spectral collocation method, again in MATLAB.
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