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Optické čerpání atomů rubidia pomocí Ti:Sa laseru
Buchta, Z. ; Rychnovský, J. ; Bartušek, Karel ; Lazar, Josef
The rapidly growing interest in production of hyperpolarized noble gasses (HpG), predominantly 3He and l29Xe for Nuclear Magnetic Resonance (NMR) experiments is driven by potentially attractive medical applications. Neither helium nor xenon is normally present in the body, so the experiments do not suffer from unwanted background signals. Among the potential medicine applications, the opportunity to image organs with low water content and/or with air spaces, such as colon or lungs, has raised a considerable interest. Current conventional imaging techniques cannot provide good images of these hollow spaces. These applications show that HpG may become a useful tool for non-invasive investigation of human lung ventilation, giving access to static imaging during breathhold, dynamics of inspiration/expiration, and functional imaging. This paper describe the way of optical pumping of Rb vapour by Ti:Sa laser which is necessary for attainment hyperpolarized state of 129Xe
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Role of proteins of Bcl family on oncogyneacology
Lidová, Lenka ; Svoboda, Petr (referee) ; Švandová, Ivana (advisor)
The Bcl-2 protein family consists of about 20 homologues important for stimulation and inhibition of apoptosis. The ratio between pro- and antiapoptotic regulators predetermines fate of the cells. Apoptosis is a physiological form of cell death which plays an important role in tissue development and maintenance of tissue homeostasis. By the apoptotic way are eliminated redundant cells and cells which can damage the organism. Cells undergo apoptosis through two major apoptotic pathways - the extrinsic or the intrinsic apoptotic pathway. Apoptotic cells are characterised by specific changes - nuclear, plasma membrane, mitochondrial etc. The contents of dead cells are packaged into apoptotic bodies. These are then recognized by macrophages and cleared by phagocytosis. Dysregulation of apoptosis may lead to many malignant, autoimmune or degenerative diseases and some developmental defect. Understanding the mechanisms of apoptosis can be an important part of the diagnostics and therapy in oncology.
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Preparation of 6-Aryl- and 6-Heteroarylpurines by [2+2+2]-Cyclotrimerizations
Turek, Pavel
Preparation of 6-Aryl- and 6-Heteroarylpurines by [2+2+2]- Cyclotrimerizations Mgr. Pavel Turek Dept. of Organic and Nuclear Chemistry, Faculty of Science, Charles University Prague 2009 The aim of my project was to synthesize new potentially biologically active arylpurines by transition metal catalyzed or mediated [2+2+2]-cyclotrimerization reactions. This approach should enable to assemble various structural motives attached to the purine skeleton. The main targets were 6-arylpurines. 6-Arylpurine derivatives have diverse types of a biological activity: some substituted 6-arylpurine bases are antagonists of corticotropin-releasing hormone or possess antimycobacterial and antibacterial activity, while 6-arylpurine ribonucleosides are potent cytostatics. These facts explain, why it is worth being interested in synthesis of this class of compounds. Until now 6-arylpurines have been mostly prepared by cross-coupling reactions of 6- halopurines with various organometallic compounds, but this approach is limited by factors like availability, reactivity and stability of the corresponding arylmetals. The synthetic strategy used in my project was based on a transition metal catalyzed or mediated cyclotrimerization of alkynes. Generally, these methods enable to assemble aromatic and heteroaromatic compounds from...
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Reactions of Alkenes Iniciated by Transition Metals Alkyls and Hydrides
Nečas, David
Reactions of Alkenes Iniciated by Transition Metals Alkyls and Hydrides David Nečas Department of Organic and Nuclear Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 40 Prague 2, Czech Republic. Keywords: C-C bond cleavage, C-C bond formation, Nickel, catalysis The C-C bond activation (cleavage) as well as the C-C bond formation under mild and simple reaction conditions are intensively sought after processes. In the course of this thesis new nickel based catalytic system was found suitable for formation of C-C bonds (cyclization of α,ω-dienes) and for cleavage of unactivated C-C bonds in allyl malonates and related compounds. Mechanistic and structural aspects of these reactions are also discussed as well as a relation of C-C bond formation (cyclization) to the C-C bond cleavage (deallylation). This work was supported by FRVŠ No. 42-202755, MŠMT No. 1M0508 Centre for New Antivirals and Antineoplastics, MŠMT No. LC 06070 Center for Structural and Synthetic Application of Transition Metal Complexes and is a part of the Research Project MSM0021620857.
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Nuclear arms control, regulation and nuclear disarmament
Bříza, Vlastislav ; Ondřej, Jan (advisor) ; Šturma, Pavel (referee) ; Kozák, Kryštof (referee)
The dissertation concludes with the main points of the research and analyses in the above mentioned four pillars and also assesses the status of the efforts for nuclear arms control and nuclear disarmament in its whole history. However, the overall picture is a mixture of successes and failures and suggests that the only way to reach nuclear disarmament in a long way through step-by-step process that would also lead to reaching higher level of world peace and stability. However, even the idea of the world without nuclear weapons has its drawbacks as the dissertation tries to show. Especially with respect to change in the US administration in the early 2009 and its approach to nuclear disarmament, there also still remain many unanswered questions that are left for further research.
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Carbocyclic analogues of nucleosides containing substituted bicyclic systems.
Šála, Michal ; Hřebabecký, Hubert (advisor) ; Černý, Miloslav (referee) ; Moravcová, Jitka (referee)
Charles University in Prague Faculty of Science Department of Organic and Nuclear Chemistry Carbocyclic analogues of nucleosides containing substituted bicyclic systems Michal Šála Ph.D. Thesis Abstract Prague 2010 Introduction Nucleoside and nucleotide analogues are of fundamental importance for all organisms. Therefore, nucleoside analogues are interesting target for drug discovery and development, mainly as potential antiviral and antitumor agents. A crucial disadvantage of natural nucleosides analogues is cleavage of the N-glycosidic bond by phosphorylases. Modification which increases resistance against enzymatic degradation is substitution of the sugar moiety furanose ring by a hydrocarbon ring. Many of such modified analogues - carbocyclic nucleosides1 - exhibit interesting antiviral activity. Several analogues containing conformationally locked bicyclic systems were also synthesized. Well known are carbocylic nucleosides with a fused cyclopropane moiety2 (bicyclo[3.1.0]hexane). Recently, novel conformationally locked carbocyclic nucleosides based on 2-oxabicyclo[2.2.1]heptane ring system were described3 (as precursors for carbocyclic locked nucleic acids). This thesis concerns the synthesis of biologically active compounds related to the carbocyclic nucleoside analogues. First part of the work is...
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Analysis of the ethical aspects of the crisis communication
Tsaruk, Khrystyna ; Antušák, Emil (advisor) ; Kopecký, Zdeněk (referee)
Analysis of the ethical aspects of the crisis communication abstract - The main goals of this Bachelor Degree Thesis are: 1) Analyze the essence of the crisis communication. 2) Analyze the ethical aspects of the crisis communication. 3) Analyze the crucial negative impact of the unethical behavior through the example of Chernobyl NPP accident. The first chapter is the theoretical part that is focused on defining the concepts directly related to the topic of the Thesis, creating an overview of the crisis communication as an important part of crisis management and as a powerful instrument in dealing with crisis situations. The second chapter deals primarily with the ethical side of the crisis communication. It provides a number of examples showing the connection between ethics and crisis communication. This part emphasizes the importance of the ethical thinking and behavior in the moments when disaster occurs in order to eliminate the negative impact upon the population, economy, and environment. The third chapter is the practical part that is focused on the description of the ethical aspects of crisis communication through the example of Chernobyl Nuclear Power Plant accident. In the end of this Thesis, there is a summary of all pieces of knowledge about the ethical aspects of the crisis communication and the Corporate Social Responsibility.
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Elektroslabé procesy v rámci efektivní polní teorie
Soukup, Petr ; Kampf, Karol (advisor) ; Kolesár, Marián (referee)
Title: Electroweak processes in the framework of effective field theory Author: Petr Soukup Department: Institute of Particle and Nuclear Physics Supervisor: RNDr. Karol Kampf, Ph.D. Supervisor's e-mail address: kampf@troja.mff.cuni.cz Abstract: In this thesis, we study electroweak processes within the framework of ef- fective field theory employing the approach of effective Lagrangians. We mainly focus on the decay process H → γγ. A complete set of SU(2) × U(1) invariant dimension- six operators is utilized. We present a brief introduction to GWS Standard model and dimension-six effective operators. One-loop Standard model contribution to the process of H → γγ is then evaluated, followed by calculation of tree-level and one-loop level dimension-six operators contribution to the same process. We then present a brief ge- neral summary of renormalization procedure in quantum field theory. Renormalization of performed calculations is implemented, and possible issues that may arise during renormalization of such non-renormalizable theory are also discussed. In the end, we discuss the obtained results, mainly the dependence of H → γγ decay rate on effective theory's free parameters and the scale of the new physics Λ. Focus is made on possible deviations from Standard model results. The results are plotted in charts....
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