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Source apportionment of PAH in middle Europe
Lhotka, Radek
The diploma thesis deals with the determination of sources of polycyclic aromatic hydrocarbons (PAH) and the changes in the PAH concentrations during the last 11 years, from 2006 to 2016. The data were sampled at National Atmospheric Observatory in Košetice, a representative station for the Central European Region. Multidimensional statistical methods as Positive Matrix Factorization (PMF), conditional bivariate probability function (CBPF), and Potential Source Contribution Function (PSCF) were used for data analyses. In the first part, the changes in concentrations of the four specific PAH, Benzo(a)pyrene (BaP), Fluoranthene (FLA), the sums of all the PAH (SUMA), and the Toxical Equivalent (TEQ) was studied. The highest concentration of all four specific PAH was detected at the beginning of the studied period. The immission limit for BaP was not exceeded. Statistically significant decreasing trend for BaP, TEQ, and SUMA PAH was identified. Second part of the thesis studied the PAH source apportionment. The study proved that the station was strongly influenced by the local domestic heating on one hand, and long-distance transportation from the west, and specifically from the northwest on the other hand. The influence of long-distance transport has an increasing trend over time, vice-versa for the...
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Challenges to the Weberian state: hybrid state and non-state actors in Iraq
Benhamou, Louis ; Kučera, Tomáš (advisor) ; Bahenský, Vojtěch (referee)
This thesis examines the relationship between the Popular Mobilization Forces and the state in post-conflict Iraq. It critically assesses their link as mutually exploitative and derives back their agency to both actors. The concept of hybridity, to characterise a behaviour that is simultaneously cooperative and competitive, is applied to both terms of the dyad. Overcoming the Western conception of the state, the research offers to consider the Iraq as a post- Weberian system where hybrid state and non-state actors collaborate to offer an alternative political order.
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Molecular mechanisms of bacterial persistence to antibiotics
Jirsová, Anežka ; Lichá, Irena (advisor) ; Branny, Pavel (referee)
The ability to persist is inherent in the vast majority of bacterial species. Persisters represent a small heterogenous fraction of the bacterial population that can tolerate antibiotics. Unlike resistant cells, which are genetically distinct from the rest of the antibiotic-sensitive population, persister cells form a genetically indistinguishable subpopulation. Persisters arise either as a result of stress caused by adverse environmental conditions, or persister subpopulation arise as a result of stochastic induction independent of the presence of stressful conditions. There are various mechanisms by which bacterial cells have been shown to induce a persistent state. Toxin-antitoxin systems and their interaction with stringent response effectors play an important role during the development of persistence. The persistent state is also affected by changes in proton-motive force (PMF) and the fluctuations in the gene expression level of energy generating enzymes of the Krebs cycle (TCA). In this thesis, persister cells are characterized and the current knowledge about the molecular mechanisms leading to the induction of persistence in bacteria is summarized. Key words: bacteria, persistence, antibiotics, stringent response, PMF, TCA
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Source apportionment of PAH in middle Europe
Lhotka, Radek ; Zíková, Naděžda (advisor) ; Mikeš, Ondřej (referee)
The diploma thesis deals with the determination of sources of polycyclic aromatic hydrocarbons (PAH) and the changes in the PAH concentrations during the last 11 years, from 2006 to 2016. The data were sampled at National Atmospheric Observatory in Košetice, a representative station for the Central European Region. Multidimensional statistical methods as Positive Matrix Factorization (PMF), conditional bivariate probability function (CBPF), and Potential Source Contribution Function (PSCF) were used for data analyses. In the first part, the changes in concentrations of the four specific PAH, Benzo(a)pyrene (BaP), Fluoranthene (FLA), the sums of all the PAH (SUMA), and the Toxical Equivalent (TEQ) was studied. The highest concentration of all four specific PAH was detected at the beginning of the studied period. The immission limit for BaP was not exceeded. Statistically significant decreasing trend for BaP, TEQ, and SUMA PAH was identified. Second part of the thesis studied the PAH source apportionment. The study proved that the station was strongly influenced by the local domestic heating on one hand, and long-distance transportation from the west, and specifically from the northwest on the other hand. The influence of long-distance transport has an increasing trend over time, vice-versa for the...
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Study of interactions of organic matter and its components via molecular dynamics
BARVÍKOVÁ, Hana
Humic acids and humates are principal components of humic substances major organic constituents of soil, peat, coal and water around the world. I was involved in research into molecular dynamics simulations of interactions of quartz surfaces with aqueous solutions of ions and small organic molecules representing basic building blocks of larger biomolecules and functional groups of organic matter. We studied interactions of molecules with surfaces for a set of surface charge densities corresponding to the experimentally or environmentally relevant ranges of pH values employing molecular mechanics, molecular dynamics and ab initio techniques. Simulated quartz surfaces covered the range of surface charge densities 0.00, -0.03, -0.06 and -0.12 C-m-2, approximately corresponding to pH values 4.5, 7.5, 9.5 and 11. As model molecules, benzoic acid, phenol, o-salicylic acid and their conjugated bases were chosen. My task was to prepare topologies and parametric models of selected organic matter basic building blocks organic molecules. I focused on studying interactions of these molecules in an aqueous environment with mineral surface quartz. The aim was to process simulation results and analyse conformations of the adsorption complexes and their thermodynamic properties such as interaction energies, free energies and adsorption geometries.
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