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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.
1

Dynamics of the soil redox conditions under different sequences of crop rotation

Novotná, Zuzana January 2001 (has links)
No description available.
2

Ztráty na výnosu a kvalitě u řepky a slunečnice při mechanickém poškození porostu

Ondrušová, Veronika January 2007 (has links)
No description available.
3

Optimalizace technologického procesu na obráběcím centru / Optimization of a technological process at the machining center

Šnejdar, Martin January 2016 (has links)
Objective of this work is optimization of a technological process at the machining center. The process of optimization concerns cost reduction and fabrication time reduction with automatization of fabrication by reducing the number of machine stoppings. It is achieved by introduction of an automatic measuring system of dimensional characteristics with system RENISHAW integrated at the machine. The objective is to achieve most elevated level of machine autonomy also by reducing the costs and fabrication time.
4

Interakce alkaloidů s přechodnými kovy II. / Interactions of alkaloids with transition metals II.

Šilhová, Markéta January 2019 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Botany Consultant: Ing. Kateřina Macáková, Ph. D. Student: Markéta Šilhová Title of Thesis: Interactions of alkaloids with transition metals II. Copper is an important component of the human body. It is involved in the right functioning of organ systems and is also a part of many important body enzymes. It is necessary to maintain a balanced amount of copper in the body in order to avoid excess or deficiency, which can lead to various diseases. The aim of this diploma thesis was to determine the copper chelating and copper reducing effects of isoquinoline alkaloids berberine chloride, canadine, corydaline, sculerine, sinactine, stylopine, tetrahydropalmatine, allocryptopine, protopine, corycavamine and cryptopine. In experimental measurements the determination of chelation of copper ions with hemytoxyline and the determination of chelation and reduction of copper ions using disodium salt of bathocuproindisulfonic acid was performed. The highest reducing activity was exhibited by scoulerine, whose structure in comparison with other alkaloids contains hydroxyl groups and which has been exhibited in the past to inhibit the growth of tumour cell. The lowest reducing activity was measured for protopine alkaloids and...
5

Interakce alkaloidů s přechodnými kovy I. / Interactions of alkaloids with transition metals I.

Rzepecká, Radka January 2019 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Radka Rzepecká Supervisor: Ing. Kateřina Macáková, Ph.D. Title of Thesis: Interactions of alkaloids with transition metals I. Copper is one of the essential trace elements that are necessary for the proper functioning of the organism. Copper is a significant component of many enzymes that affect various metabolic processes in the human body. It is important that the level of copper in the body is regulated because its deficit or excess lead to a variety of pathological conditions. Alkaloids are secondary plant metabolites that are distinguished by numerous biological activities. In this thesis the copper-chelating and copper-reducing activity of eleven isoquinoline alkaloids was measured: boldine, isocorydine, (+)-bulbocapnine, (+)-corydine, glaucine, (-)-sinoacutine, (-)-californidine, (-)-escholtzine, platycerine, (-)-fumaricine, and (+)- parfumine. Alkaloid activity was measured at four (patho) physiological pH values by a verified spectrophotometric method using two indicators: bathocuproinedisulfonic acid disodium salt and hematoxylin. Based on the results, structure-effect relationships were derived. The results show that none of the tested substances was able to chelate copper ions. In...
6

Generalizace vodních toků metodou částečné prostorové redukce / Simplification of rivers based on the spatial reduction method

Mazur, Dominik January 2020 (has links)
This master thesis is focused on cartography generalization of a rivers using collapse and partial collapse method with the usage of straight skeleton data structure. The proposed method was designed for large scale maps in geographical view and for medium scale maps in cartographic view (till 1 : 100 000). The thesis is focusing on width of a river as stand alone criteria for generalization decision. The presented solution represents set of a criteria which decides on generalization of a river. The presented thesis also solves problematic situations that exist on a river such as islands, junctions, shoulders or bifurcation. The thesis also includes proposed generalization algorithm which is using straight skeleton data structure. The algorithm is implemented in C++ programming language in Microsoft Visual Studio IDE. The algorithm uses external libraries Qt and CGAL (Computational Geometry Algorithms Library) for functioning. Algorithm results are saved in ESRI geodatabase with the usage of Python 2.7 programming language and external library ArcPy. Water areas from ZABAGED were chosen as appropriate data for testing. Achieved results of generalization are presented on test data for various scales and they are compared with base maps of Czech Republic. Keywords: digital cartography, cartography...
7

Interakce alkaloidů s přechodnými kovy IV. / Interactions of alkaloids with transition metals IV.

Loskotová, Lenka January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Bc. Lenka Loskotová Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Title of Thesis: Interactions of alkaloids with transition metals IV. Copper is a biogenic trace element that participates in the proper function of an organism. It is part of a number of enzymes and participates in metabolic processes in the human body. The level of copper in the organism should be regulated to avoid its excess or deficit, as pathologies could occur. Alkaloids are natural nitrogenous substances of alkaline nature. We find many biological activities in them. The aim of this thesis was to measure copper-chelating and copper- reducing activity of isoquinoline alkaloids: corypalmine, thalictricavine, 8-oxoberberine, fumarilin, norisocorydine and laurotetanine. Alkaloid activity was measured at different pH environments (4.5; 5.5; 6.8 and 7.5) and in the DMSO environment by a spectrophotometric method using hematoxyline and acid disodium salt bathocuproindisulfonic. Based on the results, structure-effect relationships were derived. In experimental measurement, it was found that none of us tested alkaloids showed chelating activity. Reduction activity has been demonstrated in all test substances. The lowest activity...
8

Interakce alkaloidů s přechodnými kovy III. / Interactions of alkaloids with transition metals III.

Cymbál, Martin January 2020 (has links)
Charles University Pharmaceutical Faculty in Hradec Králové Department of Pharmaceutical Botany Candidate: Bc. Martin Cymbál, DiS. Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Diploma thesis 2019/2020: Interactions of alkaloids with transition metals III., pp. 86. Copper is one of the important trace elements in the body. It regulates various enzymatic pathways. This work monitors the chelating and reducing activity of isochinoline alkaloids of the family Amaryllidaceae. The alkaloids of Amaryllidaceae have a large number of effects such as analgesic, narcotic, antiarrhythmic, antihypertensive, bronchodilatory, chemotherapeutic, antiparasitic, uteretonic, locally anesthetic, mydriatic and many other significant effects. An important representative is galanthamine hydrobromide, which is therapeutically used and is an inhibitor of acetylcholinesterase. Galanthamine type alkaloids (galanthamine, galanthamine hydrobromide, chlidanthine), lycorine type (lycorine, galanthine), haemanthamine type (haemanthnamine, vittatine) and montanine type (montanine) were studied. The methodology of the work was to determine the chelating and reducing activity with the use of the hematoxylin indicator and bathocuproindisulfonic acid, at different pH or in dimethylsulfoxide. Of the alkaloids studied, galanthamine and...
9

Interakce chalkonů s přechodnými kovy I. / Interaction of chalcones with transition metals I.

Faberová, Jana January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidat: Jana Faberová Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Title of Thesis: Interaction of chalcones with transition metals I. Iron is a biogenic metal element with unpaired d-electrons that plays a key role in the survival of unicellular organisms, plants and mammals. The electron shell of the iron atom is able to easily bind and release electrons and thus contribute to the proper function of the organism. Iron is necessary to ensure the transport of respiratory gases, cell differentiation and the functioning of some specific enzymes. However, despite the clearly positive effect of iron on human health, inappropriately low or high level of iron in the body can cause the development many diseases. Chalcones are plant polyphenols belonging to the family of flavonoids, secondary metabolites of plants. The term chalcone generally refers to a chemical structure with an ,-unsaturated ketone system based on 1,3-diphenylprop-2-en-1-on. These substances have a wide spectrum of biological activities and in the right amount can be good for human health. The aim of this diploma thesis was to monitor the iron-chelating and iron-reducting activity of selected chalcones: isoliquiritigenin, licochalcon A,...
10

Interakce chalkonů s přechodnými kovy II. / Interaction of chalcones with transition metals II.

Šulcová, Martina January 2021 (has links)
Charles University in Prague Faculty of Phramacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Martina Šulcová Supervisor: Assoc. Prof. Ing. Kateřina Macáková, Ph.D. Title of the diploma thesis: Interaction of chalcones with transition metals II. Copper is one of the essencial elements in human body which is involved in the functioning of many enzymes and metabolic pathways. Although it appears in trace amounts in the body, its functions are irreplaceable. However, the ion level must be kept in balance by the various mechanisms of the body. If there is an excess or deficiency of copper in the body, this condition can lead to the development of health issues. Chalcones are substances belonging to the group of flavonoids. Their polyphenolic structure does not have a closed ring C. Studies describe their anticancer, anti-inflammatory, antiviral, antidiabetic, antibacterial, antioxidant, immunosuppressive and other properties. Chosen substances in the group of dihydrochalcones (naringin dihydrochalcone, neohesperidin dihydrochalcone, phloretin, phlorizin) and chalcones (isoliquiritigenin, licochalcone A) were tested for their chelation and reduction activity of the copper ions in this diploma thesis. The activity was measured at different pH environments (7.5; 6.8; 5.5 and 4.5) and...

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