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Imaging of fluorescence emission signals from healthy and infected leaf tissues
BENEDIKTYOVÁ, Zuzana
Auto-fluorescence emission of plant tissues can be a powerful reporter on plant biochemistry and physiology since it originates in substances inherent to primary or secondary metabolism. Plant bodies contain a plethora of intrinsic fluorescent compounds emitting practically all wavelengths of visible light. Moreover, the spectrum of fluorescent reporter signals was recently extended by a variety of fluorescent proteins that provide a new tool to mark whole cells or sub-cellular structures, study protein localization and monitor gene expression and molecule interactions. The imaging of such fluorescence signals reveals a possibility to acquire the information from as many as millions of points simultaneously, in vivo and in a non-invasive way thereby preserving integrity of cells and whole organisms. Imaging is particularly suited to visualize heterogeneity such as a localized immune response to invading pathogens. It can be applied both at macro- as well as micro-scales in two and three dimensions. The recent advancement in microscopy, the multi-photon microscopy, has made possible to monitor fluorescence signals, such as NAD(P)H fluorescence from intact leaf interior, that have been hidden to single-photon techniques.
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Evaluation of elastic parameters for models of isolated cells
Krbálek, Jaroslav ; Fuis, Vladimír (referee) ; Burša, Jiří (advisor)
This diploma thesis focuses on computational modeling of the cell mechanical tests. The goal of this thesis is to build a cell model and to simulate compression test on this model. If necessary, the model should be adjusted so the model reflects real cell behavior. It was created the cell model reflecting cytoplasm, nucleus, membrane and cell cytoskeleton. Cytoskeleton was modeled as tensegrity structure. After this, the pressure test was simulated on this model. The behavior of the cell model and real cell was compared using the stress force. The stress force - cell deformation curve was markedly different for the cell model and the real cell. For this reason, the cytoplasm material model was adjusted. The difference between the curves was acceptable after this modification. It was found during computations that the cytoskeleton model influence on the cell load is minimal. These results does not reflects real cell behavior, which means that the model is considered inadequate for performing stress load simulation.
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Propagation of inclined cracks to the interface of ceramic laminates
Novotná, Lenka ; Trunec, Martin (referee) ; Chlup, Zdeněk (advisor)
Composite materials with laminated structure provide advantages which are utilised during component design. Low density, temperature and chemical stability are the profitable properties predetermining application of ceramic laminates. The main obstacle for wide spread of ceramic materials is their inherent brittleness. Therefore, in this thesis, the crack propagation in ceramics laminates has been extensively studied. Laminated structures with various volume fractions of components (alumina and zirconia) were prepared by electrophoretic deposition. Evaluation of crack propagation through the interface and determination of basic mechanical properties was conducted on the basis of extensive literature search. Crack deflection originated in both presence of internal stresses and differences in elastic modulus during the crack interface passing was monitored. A special type of specimen geometry was employed with the aim to set arbitrary angle between crack and interface. It was experimentally found that the degree of crack deflection is dependent on entering angle and volume fraction of components. Higher crack deflection was already found in the bulk of the test piece comparing to the test piece surface. The 3D fracture surface reconstruction generated using laser confocal microscopy was used in this detailed crack propagation study. Further basic elastic and strength characteristics of laminates were determined and compared to those obtained from monolithic materials. The validity of the mix rule for elastic characteristics was confirmed by comparing of elastics modulus. The most reliable method for elastic modulus determination was marked the dynamic resonance method due to low scatter and consistency in measurement. The flexural strength of all laminates tends to be close to the flexural strength of the weakest component. Therefore the mix rule is not applicable for flexural strength estimation on the contrary of elastic characteristics. The change of component volume fraction leads only to change of flexural strength scatter. Thanks to gained knowledge about crack propagation and basic characteristic determination will be possible to design ceramic laminates more efficiently for given needs of application.
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Numeric simulation welding of the turbine vane and rotor
Dohnal, Ivo ; Slováček, Marek (referee) ; Daněk, Ladislav (advisor)
Numeric simulation welding of the turbine vane and rotor - master’s thesis is ordered by the Siemens Industrial Turbomachinery ltd. company. Simulation welding is done in program SYSWELD. Used welding materials are X22CrMoV12-1 (turbine vane), 30CrMoNiV5-11 (rotor), TOPCORE 838 B (additional material). These are temperature-resistant and fire-resistant welding materials. The SYSWELD program works on the principle of finite elements method. By SYSWELD is done the evaluation of temperature and stress fields and material structure after welding. Here is a part , which deals with computations of welding crevices.
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Dynamism and Codification
Šipková, Milena
The author attempts a typology of the language variants. She stresses that as far as codification is concerned, apart from the langue changes of the social and territorial character especially the processes of structural character are important; within them it is necessary to distinguish especially the progressive phenomena.
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Studium transportu iontů přes modelové fosfolipidové membrány
Navrátil, Tomáš ; Šestáková, Ivana ; Mareček, Vladimír
Synthetically prepared model phospholipid bilayers (PLBs) in the form of black membranes, vesicles or supported membranes, with incorporated ionophores or real ion channels (i.e., artificially synthesized or gained from real living cells, e.g. protoplasts) are promising for study and simulations of transporting processes across the real cell membranes and the membranes surrounding sub-cellular structures. The electrochemical methods were found to be very suitable and sensitive enough for characterization of such processes.
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Computational modelling of noise inside cabin of aircraft VUT 100 Cobra
Prnka, Jiří ; Houfek, Lubomír (referee) ; Švancara, Pavel (advisor)
This master’s thesis deals with the computational simulation of low-frequency noise inside the cabin of small commercial airplane VUT 100 Cobra. For this low-frequncy range deterministic methods: Final Element Method (FEM) and Boundary Element Method (BEM) are used for simulation of the dynamic behaviour of the object. FEM has been used to compute eigenmodes and eigenfrequences of the structure of the aeroplane cabin and of the acoustic space inside cabin. Then response to harmonic excitation of engine represented by unit forces in place of contact has been computed. Obtained velocities on the surface of the cabin are then used as the basis for the noise calculation inside the cabin using BEM. After that effect of some construction modifications on sound level inside cabin are evaluated by computational modelling.
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Phase-correlation based image registration
Druckmüllerová, Hana ; Martišek, Dalibor (referee) ; Procházková, Jana (advisor)
Tato práce se zabývá použitím fázové korelace k určení vzájemné rotace, změny měřítka a posunu mezi digitálními obrazy. Fázová korelace je založena na Fourierově transformaci, proto je popsána Fourierova transformace funkcí definovaných na R^2 i diskrétní Fourierova transformace funkcí definovaných na konečném počtu bodů {0, 1, ... , N-1}^2, kde N je přirozené číslo. Dále je pozornost věnována modifikacím fázové korelace, díky nimž metoda umožňuje nalezení parametrů podobnostní transformace i mezi obrazy, které mají vysoký dynamický rozsah a slabě patrné struktury, obsahují aditivní nebo impulzní šum a jsou pořízeny pomocí různých snímačů a optických soustav. Obsahem práce jsou i modifikace metody pro snímky sluneční koróny pořízené během úplných zatmění Slunce, což patří mezi nejobtížnější úlohy registrace obrazů.
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Controled crystallisation of aluminium alloys castings poured in shell moulds
Mašková, Lenka ; Střítecký, František (referee) ; Roučka, Jaromír (advisor)
The aim of this thesis is to verify a possibility of controlling the crystallisation of aluminium alloys poured in shell moulds in order to achieve directional solidification. For this purpose, new cooling plant has been designed and fabricated. Several sample castings were produced under different initial conditions. Based on the evaluation of measured temperatures, a numerical simulation of heat transfer was created using the ProCAST software. Finally, the sample castings were sectioned into specimens that were, subsequently, metallographically polished and the evaluation of their structure with respect to the amount and types of defects was performed.
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