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Measurement of nanoparticles in 3D printing using FFF/FDM technology
Klouda, Karel ; Kubátová, Hana ; Nechvátal, Marek ; Bátrlová, Kateřina ; Roupcová, Petra
For additive manufacturing, where the material is prepared by depositing thin layers, the simplified term 3D printing is used. This process releases volatile organic compounds and ultrafine particles into the air. A number of measurements have been published on this topic for a given type of printer with a specific type of thermoplastic. The procedure for the measurement of nanoparticle concentrations (10-700 nm) and their mean diameters can be called "field" because it was carried out in a real environment with mass deployment of FFF/FDM 3D printing, with the measuring equipment moving between printers in different areas and activities: in the production of parts to be assembled in the printers; in the production of components for shields during the lockout associated with the covid-19 pandemic; in the creative workshops and laboratories of Průsa Research. The aim of these measurements in real situations was to find measures to reduce the concentration of nanoparticles. The evaluation of the results was carried out in accordance with ISO/TR 27 628 and provided for the design of technological and organisational measures to reduce the concentrations.
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Johann Georg de Hamilton. Life and Work.
Ourodová, Ludmila ; Prahl, Roman (advisor) ; Adamcová, Kateřina (referee) ; Jandlová Sošková, Martina (referee)
The content of this dissertation is the life and œuvre of Johann Georg de Hamilton, a relatively obscure painter of hunts, portraits of horses, hunting still-lifes and hunting scenes. Johann Georg de Hamilton (1672-1737), a painter belonging to a famous Scottish family, was influenced in his creative work considerably by the 17th -century Flemish painters of still-lifes and hunting scenes. He was active predominantly in Vienna and in South Bohemia, in service of Adam František, Prince of Schwarzenberg, as well as Karl VI of House Habsburg. He created hunting-themed paintings and portraits of horses to members of both the secular and the ecclesiastic aristocracy of the lands of the Austrian Empire, such as the Houses of Liechtenstein, Serényi, Althan and others. This dissertation is the very first attempt at a monographic analysis of the life and œuvre of this painter. In addition to new bibliographic data, it offers an in-depth insight into the relationship between the person who commissioned his work, Adam František, Prince of Schwarzenberg, and the painter Johann Georg de Hamilton on the basis of extant correspondence, and also attempts to present the painter's œuvre in a cultural-historical and artistic context. The dissertation mentions the first exhibition of a collection of Hamilton's work,...
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Diagnostics of lexical and semantic level of language in preschool age
Malechová, Veronika ; Šulová, Lenka (advisor) ; Morávková Krejčová, Lenka (referee)
This theses deals with diagnostic of speech development of pre-school children. Its focus is on lexical-semantic language level. The goal of my work is to trace and map diagnostic possibilities in the lexical- semantic area of of pre-school children and to introduce the international PPVT test , considering its adaptation into czech language environment. Theses consists of two parts - the theoretical and empiric. Theoretical part is concern with the most important theories and personalities in the speech development and the process of experiencing language, characteristics of pre-school period, ontogenesis of speech and the ways to evaluate vocabulary and semantics in Czech and overseas. The empiric part examines the usages of PPVT in czech environment. The survey was realised by quantitative research, using datas from 236 tested individuals. The PPVT was adapted into czech language and given to preschool children, whose results were compared with the results of american children. The outcomes of the empiric part could be a solution for future research in the area, with the purpose of adapting a testing- language instrument into czech language and widening the limited possibilities in the field of language and speech development evaluation. Keywords: ontogenesis of speech, pre-school period,...
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Study of physiological functions of betaine homocysteine S-methyltransferase and betaine homocysteine S-methyltransferase 2
Mládková, Jana ; Jiráček, Jiří (advisor) ; Šulc, Miroslav (referee) ; Kožich, Viktor (referee)
Betaine homocysteine S-methyltransferase (BHMT) and betaine homocysteine S-methyltransferase 2 (BHMT-2) are mammalian cytosolic metalloenzymes. They both participate in the metabolism of homocysteine (Hcy), specifically Hcy remethylation, mainly in liver and kidney cells. BHMT catalyzes the transfer of a methyl group from betaine to L-Hcy, yielding L-methionine and dimethylglycine (DMG). BHMT-2 catalyzes the transfer of a methyl group from S-methylmethionine (SMM) to L-Hcy as well, yielding two molecules of L-methionine. Disorders in Hcy metabolism could lead to the so called hyper- homocysteinemia and homocystinuria, which can be connected with several pathological conditions. BHMT is already relatively well characterized enzyme. Its crystal structure and reaction mechanism have been described and a series of BHMT inhibitors have been prepared. The specific inhibitors enabled further in vivo studies and, recently, Bhmt-/- mice model has been successfully developed. In contrast, the research of BHMT-2 is still at the beginning and physiological functions of the enzyme are unknown so far. The reason is that BHMT-2 is a highly unstable enzyme and also there is a lack of selective BHMT-2 inhibitors. BHMT and BHMT-2 are very similar enzymes which have 73% amino acid identity. This thesis provides new...
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Palaeoecology of selected localities of the Whetstone Horizon
Libertín, Milan ; Kvaček, Jiří (advisor) ; Teodoridis, Vasilis (referee) ; Cleal, Christopher J. (referee)
Palaeoecology of selected localities of the Whetstone Horizon In frames of the present thesis taphonomical and paleoecological processed were described in selected localities of whetstone horizon. Fossil plant assemblage known from the locality Štilec represents plant community buried in situ by volcanic ash after volcanic explosion (Pennsylvanian, Bolsov). Plant community exhibits relatively low diversity assemblage of herbaceous and subarborescent plants. This unique taphocoenose was interpreted as pioneer assemblage growing in partly drained lake. In the locality Ovčín the peat bog of Lower Radnice Seam was buried during the same volcanic eruption by volcanic ash. Up to now 5 excavations were recovered of the area of seats over 150 m 2 on two sites which are approximately 40 m distant from each other. In this area 27 morphotaxa of fossil plant was recorded. They represent 20 whole plants. Fossil plant remains represent fossil plant assemblage dominated by lycopod plants of planar (rheotrophic) swamp situated in narrow palaeovalley with active fluvial system. Second part of the thesis is focused on systematic descriptions of fossil plant taxa from localities of the Whetstone horizon. A monotypic genus Huttonia and species Huttonia spicata from Class Sphenopsids was emended. Further there were described...
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Effect of Amino Acids Derivatives And Ceramides on Skin Barrier Function
Janůšová, Barbora ; Vávrová, Kateřina (advisor) ; Balgavý, Pavol (referee) ; Rabišková, Miloslava (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of inorganic and organic chemistry Candidate: Mgr. Barbora Janůšová Supervisor: doc. PharmDr. Kateřina Vávrová, Ph.D. Title of Doctoral Thesis: Effect of amino acids derivatives and ceramides on skin barrier function The main goal of my thesis was to contribute to the understanding of behavior of the ceramides and skin barrier function modulators based on amino acids derivatives, as well as to elucidate the relationship between their structure and activity. Transdermal permeation enhancers are compounds that temporarily decrease skin barrier properties to promote drug flux. In the first part of my thesis, enhancers with amino acids (proline, sarcosine, alanine, β-alanine, and glycine) attached to hydrophobic chain(s) via a biodegradable ester link were investigated. The double-chain lipid-like substances displayed no enhancing effect, whereas single-chain substances significantly increased skin permeability. The most active enhancer - proline derivative L-Pro2 reached enhancement ratios of up to 40 at 1% concentration, which is higher than that of the well-established and standard enhancers Azone, DDAIP, DDAK, and Transkarbam 12. No stereoselectivity was observed. L-Pro2 acted synergistically with propylene glycol and...
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Effects of chemopreventive compounds on cytochrome P450s
Křížková, Jitka ; Hodek, Petr (advisor) ; Helia, Otto (referee) ; Václavíková, Radka (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Science Department of Biochemistry Effects of chemopreventive compounds on cytochrome P450s Summary of Ph.D. Thesis RNDr. Jitka Křížková Supervisor: prof. RNDr. Petr Hodek, CSc. Prague 2010 Introduction 1 Introduction According to the World Health Organization statistics, cancer is one of the leading causes of death in the human population worldwide for more than 50 years. Moreover, colorectal and gastrointestinal tract cancers are one of the main types of cancer leading to overall cancer mortality. Prevention consisting in a healthy lifestyle and a natural diet is suggested to be one of the main approaches to reduce cancer risk. In recent years, the consumption and use of dietary supplements containing concentrated chemopreventive phytochemicals increased dramatically. Flavonoids, as the most popular representatives of chemopreventive compounds, present in foods (fruits, vegetables, herbs, beverages) and dietary supplements have the potential to modulate the activity of xenobiotic-metabolizing enzymes [Hodek et al., 2002]. Among proteins interacting with flavonoids, cytochrome P450s (CYPs), monooxygenases metabolizing xenobiotics (e.g. drugs, carcinogens), play the most prominent role. The two members of CYP1A subfamily, CYP1A1 and CYP1A2, are involved in the...
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Work of architect Jakob Gartner in the territory of Austria-Hungary
Halusková, Tereza ; Biegel, Richard (advisor) ; Prahl, Roman (referee)
(in English): The subject of this thesis is the work of a Jewish architect Jakob Gartner (1860 - 1921) in the fields of sacral and mundane architecture. The paper is limited to structures build on the territory of Austria-Hungary. The beginning of the thesis is dedicated to the emerging emancipation of Jews and their influence on the whole society. Right after is the introduction to the theoretical discussion about the style and form, which were preceding the newly created architecture. After this introduction, the paper is pursuing the person of the architect Jakob Gartner himself. The key part of the thesis presents constructed and only planned synagogues across the countries. In the end the focus dedicated to constructed, mostly Viennese, mundane buildings and constructions like a maternity hospital, villa and a larger number of apartment buildings. The final part of the paper is a complete list of the work of Jakob Gartner, which includes as well the buildings built in the regions of Moravia and Silesia.
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Analysis of factors affecting human preferences and thus effort given to the conservation of animal species
Lišková, Silvie ; Frynta, Daniel (advisor) ; Komárek, Stanislav (referee) ; Sedláček, František (referee)
Recently, it was reported that humans treat animals that they perceive as aesthetically attractive unequally to the "ugly" ones, turning more attention to them and setting more conservation programs for their protection. The aim of this thesis was to investigate the issue focusing around animal beauty in more detail by examining human preferences towards one of the most popular animal taxon, the birds. In three subsequent studies, we assessed human preferences towards selected bird species: all members of the order of parrots, randomly selected representatives of all non- passerine bird families, and all members of the vividly colored passerine family Pittidae. The first study revealed that the preferred parrots were kept in zoos in higher numbers, regardless of their conservation priority (IUCN status). We discussed possible consequences of this finding and the benefits that may arise in the light of animal conservation if this bias in species preferences was to be considered by conservation specialists. We also found that people preferred long-tailed parrots possessing blue and yellow colors over green ones, which were probably perceived as dull and uninteresting as the majority of the parrots are fully or partially green. In the next two studies, we found that shape, pattern, and overall...
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Development and Application of High Performance Separation Methods in Connective Tissue Analysis
Braun, Martin ; Štulík, Karel (advisor) ; Pacáková, Věra (referee) ; Samcová, Eva (referee)
24 Annotation: This work is concerned with the development and application of high performance separation methods suitable for determination of clinically considerable fragments of collagen and elastin as the most important proteins of connective tissues. For their analyses, various chromatographic and electrophoretic methods have been used, including high performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MEKC). This work has aimed at optimization of the developed and modified analytical separation procedures and methods and their utilization for determination of clinically important markers of connective tissue degradation. The key validation parameters of the analytical methods used in this work were evaluated too, which enabled their comparison with other approaches. One of the most important results of this work is thus high sensitivity, precision, repeatability and robustness of the methods which was found in a number of biological sample types. Successful was also very good HPLC separation of the analyzed cross-links in both collagen and elastin tissues. High performance methods are described which have been suggested and optimized for separation and quantitative determination of pentosidine, pyridinolines and...
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