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Quantitative description of textures in volcanic rocks: Case study of trachybasalt from Dubičná
Ditterová, Hana ; Dolejš, David (advisor) ; Rapprich, Vladislav (referee)
- iii - ENGLISH ABSTRACT Quantitative description of textures, in particular, the distribution of grain sizes, is becoming a powerful tool for interpreting kinetic processes that govern crystallization of igneous rocks. Variation in grain size are frequently represented by logarithm of population density vs. linear crystal size, where the majority of igneous rocks forms a linear trend. Its slope provides an estimate of characteristic grain size, or growth rate and crystallization time, whereas the intercept provides the nucleation density. The log-linear trend is predicted to result from kinetic nucleation and growth processes only, whereas its modifications such as kinks or curvature are due to mechanical separation or accumulation of crystals, magma mixing or Ostwald ripening (coarsening) in the presence of melt. In order to investigate the true, three-dimensional crystal size distribution, the raw two-dimensional data acquired from thin sections or rock slabs must be processed by various stereological methods. We illustrate application of quantitative textural measurements to distribution and origin of clinopyroxene crystals in a trachybasaltic lava flow from Dubičná near Úštěk. This effusion belongs to Cenozoic volcanic products in the Bohemian Massif, specifically to its main Eocene-Miocene stage in...
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Characterization of recombinant fragment of an antibody against CD3 marker.
Písačková, Jana ; Maloy Řezáčová, Pavlína (advisor) ; Obšil, Tomáš (referee)
Monoclonal antibody MEM-57 recognizes CD3 antigen expressed on peripheral blood T-lymphocytes. CD3 surface glycoprotein complex associates with T-cell receptor and is responsible for the transduction of activation signal. Antibody MEM-57 has, therefore, a large diagnostic and therapeutic potential. It could be used in autoimmune diseases diagnostics, for classification of T-cell leukemias and, as an immunosuppressant, in transplantation. The most promising therapeutic use of MEM-57 antibody would be the construction of a "Bispecific T-cell Engager" (BiTE) antibody format with potential application in cancer therapy. In this format, single-chain variable fragment (scFv) of MEM-57 would be fused with an anti-tumor antigen scFv. The thesis is focused on biochemical and biophysical characterization of MEM-57 antibody scFv fragment. Recombinant antibody fragment scFv MEM-57, equipped with the pelB leader sequence, c-myc tag and His5 tag, was produced from a pET22b(+) vector into the periplasmic space of E. coli BL21 (DE3). Two-step purification protocol, employing nickel chelation affinity chromatography and ion-exchange chromatography, was developed to obtain high yield of pure protein. The antigen binding activity of scFv MEM-57 was confirmed by flow cytometry. Structural information on scFv MEM-57...
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Methods of primary influencing steel and steel ingot structures
Stejskal, Marek ; Záděra, Antonín (referee) ; Blažík, Petr (advisor)
This bachelor thesis is focused on the ways of influencing metal structure during it’s solidification in the mold that leads to changes in mechanical properties. In the first part there is explained the principle of metal crystalization, it’s types and mechanisms, there is also described the issue of metal solidification in the mold. In the second part of the thesis there is a general view of methods being used for primal influencing of steel structure. The principles and ways of use for these methods in foundry industry are explained.
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The study of polymorphism and optimization of active pharmaceutical ingredients crystallisation
Novák, David ; Ing.Ladislav Cvak, Ph.D. (referee) ; Ing.Roman Gabriel (advisor)
Active pharmaceutical ingredients (APIs) are frequently delivered to the patient in the solid-state as part of an approved dosage form (tablets, capsules, etc.). Understanding and controlling the solid-state chemistry of APIs is therefore an important aspect of the drug development process. APIs can exist in a variety of distinct solid forms, including polymorphs, solvates, hydrates, co-crystals and amorphous solids. Each form displays unique physicochemical properties that can profoundly influence the bioavailability, manufacturability, stability and other performance characteristics of the drug. Most APIs are purified and isolated by crystallisation from an appropriate solvent during the final step in synthetic process. The main objective of a crystallisation process is to produce crystals with desired properties such as particle size distribution (PSD), shape and purity. All pharmaceutical dosage forms must be produced in uniform units, and good content of uniformity is only possible when the size of the active component is carefully controlled. For on-line control of crystallisations of Quetiapine Fumarate to achieve desired PSD and no changed physicochemical purity was used the Lasentec Focus Beam Reflectance Measurement (FBRM) system.
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Phosphate binders
Kalina, Lukáš ; Ptáček, Petr (referee) ; Šoukal, František (advisor)
The work deals with the preparation and study of polyphosphate composites. Aluminum phosphates provide some unusual properties like high-heat resistance in terms of inorganic binders. The addition of chromium in the form of Cr2O3 or directly the bond with the aluminum-chromium-phosphate can improve the properties of this binder. Highly viscous Al2Cr(H2PO4)9 and Al3Cr(H2PO4)12 binders were prepared by dissolving Al(OH)3 and CrO3 in 85% phosphoric acid, and mixed with Al2O3 and Cr2O3 fillers. The composites were cured in the furnace at 150 °C for 24 h under pressure of 10 MPa. During the annealing at temperatures up to 1 500 °C changes in chemical structure of the cured composites were observed, leading to the understanding of the creation of crystalline phases and their eventual changes. The characterization of binders was mainly based on FT-IR, EDAX, TG-DTA and optical microscopy analyses.
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Plastic materials and their treatment
Kopečný, Aleš ; Zemčík, Oskar (referee) ; Osička, Karel (advisor)
This research the basic empirical knowledge about the processing of plastic materials. The following are analyzes of the nature of plastic materials and analysis of the use of these materials in the engineering industry. This paper deals with the technological methods of processing plastics. Specifically, it is done as a summary of information about the technologies needed for the production of molds for plastics. Key words
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Structural studies of mutant variants haloalkanedehalogenase DhaA106
MALCHER, Pavel
The aim of the thesis was to compare the haloalkane dehalogenase DhaA106 with other studied protein mutant variants. For diffraction analysis, it was necessary to growappropriate crystals of DhaA106 protein. Crystallization experiments were performed by standard sitting drop method. Obtained rod crystals were used for diffraction analysis. During diffraction measurement completeset of 500 diffraction images were obtained, from which the electron density map was formed and the spatial model of the molecular structure of DhaA106 dehalogenase was created. Alternative conformation of amino acids, water molecules, parts of precipitating solution and chloride ion inthe active sitewere subsequently added into the model structure. The final structure of the moleculewas refined and validated. Subsequently, the amino acids pentade in the active site and whole protein structure were analyzed . Values of validation and refining and interatomic distances in the active site were compared with several variants mutant dehalogenase DhaA, as well as the precipitating solutions used for crystallization and diffraction data collection. In the last step of the work interactions of the selected substrate with the protein surface in the vicinity of the tunnel connecting the active site of the surfacewere studied. Mentioned interaction study was based on the principle of combination of the Monte-Carlo methods with protein structure prediction algorithms.
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Structure-modelling studies of the haloalkane dehalogenase LinB
ŘEŽÁBEK, Josef
The main aim of this bachelor thesis was structure-dynamics study of LinB86 mutant variant protein isolated from the soil bacterium Sphingobium japonicum UT26. Standard and advanced protein crystallization techniques, basis of solving protein structures from diffraction data and study of enzyme structure and dynamics with the use of standard SW for molecular modelling were applied.
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