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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Studium karbonatace alkalicky aktivovaných systémů / Study of carbonatation in alkali activated systems

Suchý, Rostislav January 2016 (has links)
The carbonation of the building materials based on the ordinary Portland cement is relatively well-known and extensively studied phenomenon. Conversely mechanism, reaction products and factors affecting the carbonation of the alkali activated materials are still not sufficiently clarified. In this work, the progression of the carbonation of the alkali activated materials under different conditions was investigated. The reaction products and the microstructural changes were determined by XRD respectively SEM-EDX analysis. The corrosive conditions due to the decreasing of the pH of the binders by the carbonation were observed by XPS analysis of the steel fibers. The carbonation of the alkali activated samples was compared with the reference samples based on the Portland composite cement. Besides these analyzes, the mechanical properties of the binders were monitored.
22

Studium mechanismu působení přísad redukující smrštění v alkalicky aktivovaných materiálech / On the mechanisms of shrinkage reducing admixtures in alkali activated materials

Komosná, Kateřina January 2017 (has links)
This thesis is focused on the principles of behavior of shrinkage reducing agents (SRA) in alkali-activated materials based on blast furnace slag. The main focus of this work is selecting the most suitable admixture based on experiments, by which will be achieved through minimal shrinkage and will have negative effect on the properties of alkali-activated blast furnace slag at the same time. In experimental section of this work, the surface tension as individual additives as their mixtures with pore solution were measured primarily. Then the testing samples composed of blast furnace slag, water glass and addition of SRA were prepared. Of these samples was measured shrinkage and weight loss. Moreover, their mechanical properties such as flexural and compressive strength were monitored. Next, the beginning and the end of solidification was studied using the Vicat device and last but not least workability. The hydration process of alkali-activated materials with SRA was measured calorimetrically. Finally the microstructure in prepared samples was observed using scanning electron microscopy (SEM-EDS) and the total porosity was determined by mercury porosimeter.
23

Kineziologická analýza vybraných technik v zápase řecko-římském / Kinesiological analysis of selected techniques in greco-romain wrestling

Žižka, Jan January 2017 (has links)
Title: Kinesiological analysis of selected techniques in greco-romain wrestling Objective: The aim of this Thesis is to measure the extent to which various muscles are involved during the practice of the wrestling technique body lock, lift and suplex. It also considers the order in which the muscles are involved. The research applies surface electromyography. Methods: The theoretical part of this Thesis is predominantly based on the method of analysis and synthesis of the specialized literature. In the practical part, the surface electromyography was used to measure which muscles are involved in the body lock, lift and suplex. Subsequently, the difference of the motion performance of the four probands was evaluated. Furthermore, the timing of muscle activation was monitored. Results: The evaluation of the result showed that musculus rectus femoris is the most involved in the movement and the least musculus obliquus externus abdominis. In addition, it was found that m. Obliquus externus abdominis is involved first, while the last one is involved with m. Biceps femoris. Key words: Wrestling, electromyography, quality of movement, muscle activation
24

Vliv aktivace žírných buněk na organizaci mikrotubulů / The effect of the mast cell activation on the microtubule organisation

Hájková, Zuzana January 2011 (has links)
The activation of bone marrow-derived mast cells (BMMCs) induces a number of cell processes such as degranulation, proliferation and cytoskeleton rearrangements. Although microtubules are important in these processes, molecular mechanisms that control changes in microtubule organisation during cell activation are unknown. Activation of BMMCs can be achieved in several ways. Under physiological conditions, the aggregation of IgE receptors (FcRI) on the surface of BMMCs leads to the initiation of specific signaling pathways. Cells can be also activated nonspecifically by a tyrosine phosphatase inhibitor pervanadate, or by thapsigargin that inhibits Ca2+ ATPase pumps located on the endoplasmic reticulum. In this diploma thesis it was found out that rapid morphological changes can be monitored when BMMC are immobilised on the fibronectin before their activation. It was proved that specific and nonspecific activation events lead to microtubule reorganization, as well as to generation of a large number of microtubule-dependent protrusions. In the course of FcRI aggregation, generation of microtubule protrusions depends on the activity of Src family protein tyrosine kinases and on the intracellular Ca2+ concentration. STIM1, an endoplasmic reticulum Ca2+ sensor, which participates in the activation of...
25

Regulační mechanizmy reorganizace mikrotubulů v aktivovaných žírných buňkách / Regulatory mechanisms of microtubule reorganization in activated mast cells

Rubíková, Zuzana January 2017 (has links)
Microtubules (MTs) are highly dynamic structures essential for the spatio-temporal intracellular organization and transport, signal propagation, cell differentiation, motility and division. To perform these roles, MTs create arrangements capable of fast and precise adaptation to various signals. MTs are under the control of many factors regulating MT nucleation, stability and dynamics. Bone marrow-derived mast cells (BMMCs) are important immune system cells, which can cause serious diseases if their functions are deregulated. Although MT reorganization during BMMC activation is well established, the molecular mechanisms that control their remodelling are largely unknown. In the presented thesis we functionally characterised GIT1/βPIX signalling proteins, PAK1 kinase, and Ca2+ signalling in the regulation of MT nucleation in BMMCs and other cell types. We also elucidated the function of miltefosine (hexadecylphosphocholine), a promising candidate for the treatment of mast cell-driven diseases. We found that GIT1/βPIX signalling proteins are γ-tubulin-interacting proteins associating with centrosomes in BMMCs. MT nucleation is positively regulated by GIT1 and Ca2+ , whereas βPIX is a negative regulator of MT nucleation in BMMCs. Cytosolic Ca2+ affects γ-tubulin properties and stimulates the...
26

Dřevokompozity s alkalicky aktivovanou popílkovou matricí / Alkali Activated Fly Ash Composites with Wooden Filler

Brýdl, David January 2012 (has links)
This thesis examines the possibility of creating composite mainly from waste materials. The matrix of this composite was prepared from fly ash type F, which was activated by sodium water glass. Wood chips were used as a filler. This thesis includes theoretical and experimental parts. The theoretical part deals with the most important issues of wood composites with an inorganic matrix as well as basic components of investigated composite, ie alkaline activated fly ash and wood. In the experimental part, the fly ash pastes were prepared, from which the most suitable mixture was chosen for the composite preparation. Properties of wood composite with alkali activated fly ash matrix were investigated depending on the dose of wood chips.
27

Molekulární mechanismy polymodální regulace TRPA1 receptoru / Molecular mechanisms of polymodal regulation of TRPA1 receptor

Sinica, Viktor January 2021 (has links)
The TRPA1 channel is a universal, nociception-mediating cellular sensor activated by various environmental irritants, potentially harmful physical modalities and endogenous mediators of pathophysiological processes. The polymodality of TRPA1 channel allows the activation stimuli to further enhance or suppress each other's effect. While this modulation effect has its physiological importance in promoting the protective cellular and behavioral mechanisms, it may result into the unpleasant pain-related effects accompanying the chronical pain caused by aberrant TRPA1 channel activity. In order to effectively and selectively target the synergic properties of TRPA1 modulators, while preserving the sensitivity to the environmental threads, the knowledge of the mechanisms of polymodal regulation at the molecular level are required. This doctoral thesis aims at the elucidation of three main mechanisms of TRPA1 regulation: 1) the regulation via intracellular signaling cascades and phosphorylation, 2) the interaction with membrane phospholipids and 3) the temperature-driven gating. The results presented in the thesis show that the effects of the inflammatory mediator bradykinin are decreased by the low-frequency high-induction electromagnetic field used in magnetotherapy. We have identified a residue S602...
28

Identifikace nového mechanismu regulace Lck zprostředkovanou její C-terminální sekvencí / Identification of a new mechanism of Lck regulation via its C-terminal sequence

Valečka, Jan January 2014 (has links)
T-cell activation is a complex process crucial for a proper function of immune system. It has been extensively studied and its main features are well understood. However, some of the events involved in T-cell signalling are still unclear. After T-cell receptor stimulation, Src-family kinase Lck drives the initiation of signalling by tyrosine phosphorylation. Phosphorylation of several downstream targets is dependent on the redistribution of Lck to the different compartment of the plasma membrane, called lipid rafts. In lipid rafts, active Lck is juxtaposed and activates raft-resident substrates which then trigger downstream signalling. The critical in this process is the mechanism of Lck translocation to lipid rafts which has not been studied so far and represents the topic of great academic and clinical interests. Previously, we identified the adaptor protein RACK1 as a candidate protein mediating the redistribution of Lck to lipid rafts by linking it to the microtubular network. In this thesis, we analysed the structural features and functional role of RACK1 in its interaction with Lck. We show here, using the SYF cell lines expressing the wild type and various mutated forms of Lck, that intact SH3 or SH2 domains of Lck are required for an effective RACK1-Lck complex formation. We also documented...
29

Potravinová alergie na proteiny pšeničné mouky / Food allergy to wheat flour proteins

Šotkovský, Petr January 2013 (has links)
THESIS SUMMARY Food allergy is one of the frequent disorders and its incidence in paediatric as well as adult population is continuously rising, having doubled in the last two decades. Although wheat belongs to major food allergens and is a staple food in most diets, we have only little knowledge of wheat proteins causing IgE mediated hypersensitivity reaction. Diagnostic approaches of food allergy to wheat have a high sensitivity, but low specificity. Poor predictability and specificity may be associated with the insufficient purity of wheat extracts used in sIgE assays or with the lack of major allergens in these extracts. In the first step, we characterized 19 potential allergens recognised by IgE Abs of allergic patients, using proteomic techniques (1-DE, 2-DE, MALDI-TOF, QTOF and LCQDECA nLC-MS/MS ion trap technique). We identified these IgE-binding molecules such as: α-amylase inhibitors, β-amylase, profilin, serpin, β-D-glucan exohydrolase and 27K protein. To quantify sIgE in patient's sera we developed ELISA using the whole wheat extract and two commercially available α-amylase inhibitors. Second, we developed a procedure that allows isolation of wheat allergens from natural sources using Rotofor cell and HPLC. Twenty-seven potential wheat allergens have been successfully identified; of these, the...
30

Controlling vývojových nákladů / Controlling of Development Costs

Voborníková, Hana January 2012 (has links)
The thesis deals with the theme of controlling of development costs in the company Škoda Auto. The work is divided into two main parts. The beginning of this work is focused on theoretical determination of definition of controlling, basic structure, reporting, then issue of cost management and activation of intangible assets is defined. The practical part of the thesis describes the company Škoda Auto and the location of controlling department inside the company. At the end of the work there are analysis of the development cost, conditions for activating and proposal for optimizing methodology to activate the development cost.

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