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Surface-enhanced resonance Raman scattering of Zn(II) porphyrins in systems with aggregated and non-aggregated Ag nanoparticles
Spáčil, Dušan ; Vlčková, Blanka (advisor) ; Procházka, Marek (referee)
In this diploma thesis, SERRS(Surface - enhanced resonance Raman Scattering) and SERS (Surface - enhanced Raman Scattering), surface of plasmon extinction spectra and TEM images of systems with tetracationic zinc porphyrin ZnTMPyP and silver nanoparticles (Ag NPs) were studied and interpreted. The systems with isolated nanoparticles and the systems with compact aggregates were investigated. The systems with isolated nanoparticles were prepared by addition of ZnTMPyP to hydrosol of Ag NPs. NaCl was added to this system and so compact aggregates were prepared. SERRS and SERS spectra of ZnTMPyP were studied at excitation wavelengths λexc= 441.6 nm a 532 nm. Firstly, stationary systems and secondly dynamic development of hydrosol Ag NPs → Ag NPs/ ZnTMPyP → Ag NPs/ ZnTMPyP/ NaCl systems for 680 s was investigated. Time evolution of SERRS and SERS spectra were analyzed by factor analysis (FA) and time evolution of spectra extinction plasmon were measured. FA showed a strong increase of the signal of ZnTMPyP after the addition of NaCl, i.e. after conversion of isolated nanoparticles to compact aggregates. In these systems with high concentration of ZnTMPyP the increase of signal was succeeded by its decreased. With help of FA the limit of SERRS spectral detection (λexc= 441,6 nm) and limit of SERS spectral...
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Coagulation of organic matter produced by phytoplankton
Načeradská, Jana ; Pivokonský, Martin (advisor) ; Benešová, Libuše (referee) ; Janda, Václav (referee)
This dissertation thesis focuses on the removability of algal organic matter (AOM) by coagulation during water treatment and also on the influence of AOM on the coagulation of other substances present in source water. Special emphasis is put on the description of coagulation mechanisms. The effectiveness of AOM removal by coagulation was investigated by coagulation tests performed with optimized doses of coagulants (aluminium or ferric sulphate) under different pH values. Peptides and proteins contained in cellular organic matter of cyanobacterium Microcystis aeruginosa were used in the experiments since they have been previously reported to disturb the coagulation process. Moreover, peptides and proteins underwent coagulation experiments together with kaolin particles, representing clay particles in turbid waters, in both the presence and absence of coagulants to investigate the effect of AOM on the coagulation of turbid waters. To enable the description of coagulation mechanisms, AOM were characterised in terms of charge, functional groups, molecular weight and ability to form dissolved complexes with coagulant metals. The experimental results demonstrated that the removability of peptides and proteins is greatly dependent on pH value and on the properties of the involved particles or molecules....
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Aggregation of bull seminal plasma protein
Boháček, Hanuš ; Liberda, Jiří (advisor) ; Hýsková, Veronika (referee)
Mammalian fertilization is a sequence of unique and fascinating events, during which seminal proteins are of crucial role. In case of bull (Bos taurus), proteins of seminal plasma (BSP), especially its major component PDC-109, are known to be in aggregated forms, but little is known about mechanism of forming aggregates and their biological function. In present thesis we discovered some interesting properties of PDC-109 and BSP proteins. We found that concentration of these proteins influences their aggregation state significantly, which can be of great biological importance. Separation of seminal proteins by size exclusion chromatography revealed three main fractions denoted I, II and III, with apparent molecular weights of Mr > 150 000, Mr = 30 000 and Mr = 13 000, respectively. In case of PDC-109, molecular weights of theese fractions were retained even after purification procedure, which implies very stable interactions in forming of aggregates. In addition, there was a difference in distribution of PDC-109 glycoforms among fractions, which can be related to the fact, that theese fractions have different sperm membrane binding patterns as we determined by fluorescence microscopy. However, further experiments are needed for better understanding this issue.
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Simulace agregačního chování
Tomek, Jakub ; Brom, Cyril (advisor) ; Holan, Tomáš (referee)
Many breeds of cockroaches living in nature form aggregations. In this the- sis, we are looking for evolutionary advantages provided by the aggregation behavior. Because of the difficulty of testing evolutionary hypotheses on real cockroaches, we decided to use a multi-agent simulation instead. We present several models which test certain hypotheses coming from various areas of cock- roach life. Hypotheses on protection against predators, effective use of food from corpses of other cockroaches have been confirmed. Also, we provide an explana- tion of cannibalism among cockroaches. On the other hand, certain hypotheses were rejected, for example, the hypothesis concerning effective use of feces of other cockroaches. Our results may be used in further research on cockroach behavior. Furthermore, since aggregation as a general process appears in other areas of natural sciences, it is possible to use our results in them as well. 1
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Collective Evaluation of quality of movie and serial production on Czech-Slovak Movie Database on http: www.csfd.cz
Vychytil, Václav ; Švelch, Jaroslav (advisor) ; Bednařík, Petr (referee)
Diploma thesis is entitled, "Collective Evaluation of Quality of Movie and Serial Production of Czech-Slovak Movie Database on http://www.csfd.cz". The main focus of this thesis is on the aggregated evaluation study of quality of movies in several internet movie databases, primarily in CSFD and IMDb. The study also defines these internet databases in the context of social discourse, briefly informs about the history of these databases, and introduces the reader into their functioning. Additionally concerning the quality of movies, databases represent the main authority, and sorting of the movies according to their 'colour' in CSFD is considered a form of agenda-setting. This study discusses the issues of quality, through analysis in an attempt to determine the quality of movies on the database. Much of the thesis discussion revolves around the author's research, which was carried out from September 2011 till the end of March 2012. Unfortunately, because of the extent of diploma thesis and the methodology used in the research, it was not possible to analyze serial production in more detail.
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The assesment of trombocyte function by optical and impendance agregometry
Malíková, Lenka ; Stiborová, Marie (advisor) ; Poljaková, Jitka (referee)
Introduction: Platelets have an important role in the process of haemostasis in which they form blood clot generation. In some cases it is necessary to suppress activity of platelets by antiplatelet drugs to prevent life threatening states. Acetylsalicylic acid (ASA) and clopidogrel can influence the mechanism of primary haemostasis by inhibition of platelet function. This process has to be controlled. Clopidogrel is used for prevention of thrombotic states. The active form of clopidogrel is formed by cytochrome P450 3A4. Clopidogrel binds to the receptor P2Y12 instead of ADP, so platelets cannot be activated. The effect of clopidogrel is very variable. It is known that there is unresponsiveness to clopidogrel in 5-30 % patients. Acetylsalicylic acid acetylates cyclooxygenase and blocks the conversion of arachidonic acid to tromboxan A2, so platelets cannot be activated. ASA treatment is effective, but in some patients can appear so called aspirin resistance (AR). Possible unresponsiveness to the therapy is the reason why it is suitable to monitor antiplatelet therapy, which may be provided by various methods. Thesis target: To detect normal range in measurement of healthy control group, evaluate efficiency of clopidogrel and ASA and to determine which method (LTA - Light Transmission Aggregometry...
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Coagulation of organic matter produced by phytoplankton
Načeradská, Jana
This dissertation thesis focuses on the removability of algal organic matter (AOM) by coagulation during water treatment and also on the influence of AOM on the coagulation of other substances present in source water. Special emphasis is put on the description of coagulation mechanisms. The effectiveness of AOM removal by coagulation was investigated by coagulation tests performed with optimized doses of coagulants (aluminium or ferric sulphate) under different pH values. Peptides and proteins contained in cellular organic matter of cyanobacterium Microcystis aeruginosa were used in the experiments since they have been previously reported to disturb the coagulation process. Moreover, peptides and proteins underwent coagulation experiments together with kaolin particles, representing clay particles in turbid waters, in both the presence and absence of coagulants to investigate the effect of AOM on the coagulation of turbid waters. To enable the description of coagulation mechanisms, AOM were characterised in terms of charge, functional groups, molecular weight and ability to form dissolved complexes with coagulant metals. The experimental results demonstrated that the removability of peptides and proteins is greatly dependent on pH value and on the properties of the involved particles or molecules....
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Nanoparticles formed by complexes of copolymers with low-molar-mass compounds
Vojtová, Jana
This thesis is focused on mixed systems of various copolymers (double hydrophilic block and gradient polyelectrolytes, hydrophobic graft copolymers) and low-molar-mass compounds (sodium dodecyl sulfate as a representative of a ionic surfactant or superparamagnetic iron oxides in the form of nanocrystals). The electrostatic and hydrophobic interactions in the studied systems in aqueous solutions leading to aggregation behavior and to the formation of co-assembled nanoparticles were investigated by combination of scattering and microscopy techniques, including light, X-ray and neutron scattering, electron microscopy and atomic force microscopy. Powered by TCPDF (www.tcpdf.org)
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Prediction of the Effect of Mutation on Protein Solubility
Velecký, Jan ; Martínek, Tomáš (referee) ; Hon, Jiří (advisor)
The goal of the thesis is to create a predictor of the effect of a mutation on protein solubility given its initial 3D structure. Protein solubility prediction is a bioinformatics problem which is still considered unsolved. Especially a prediction using a 3D structure has not gained much attention yet. A relevant knowledge about proteins, protein solubility and existing predictors is included in the text. The principle of the designed predictor is inspired by the Surface Patches article and therefore it also aims to validate the results achieved by its authors. The designed tool uses changes of positive regions of the electric potential above the protein's surface to make a prediction. The tool has been successfully implemented and series of computationally expensive experiments have been performed. It was shown that the electric potential, hence the predictor itself too, can be successfully used just for a limited set of proteins. On top of that, the method used in the article correlates with a much simpler variable - the protein's net charge.
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The role of proteostatic mechanisms in neurodegenerative diseases
Zezulová, Kristýna ; Vodička, Petr (advisor) ; Marková, Vendula (referee)
Protein homeostasis (proteostasis) plays an important role in maintaining normal cell function and viability. Neurons are particularly vulnerable to proteostasis dysregulation, resulting in damage, dysfunction, and neuronal death, as manifested in many neurodegenerative diseases. One of them is Huntington disease, hereditary neurodegeneration with autosomal dominant inheritance. Expansion of the CAG repeats in the huntingtin gene is translated into an abnormally long glutamine chain in huntingtin protein, leading to disruption of neuronal proteostasis. The primary affected area of the brain is the striatum of the basal ganglia. Disease is progressive, the onset of symptoms usually occurs in adulthood, and after many years leads to the death of the patient. Despite intensive research, disease pathology is still not fully understood, treatment is still only symptomatic and new studies, together with a deeper understanding, also raise many new questions. Through the complexity of the issue, the study of proteostasis in neurodegeneration can bring not only possible implications for therapy, but also could go deeper into the understanding of stress, memory or aging processes.
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