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Factors determining species diversity and species composition of abandoned fields
Procházka, Tomáš ; Karlík, Petr (referee) ; Münzbergová, Zuzana (advisor)
6 Abstract Factors determining plant species composition and species diversity of former fields in Slavkovský les The secondary succesion is relatively thoroughly examined phenomenon, but quite little is known about wet secondary grasslands developed on the former farmland. There is a large number of abandoned fields in the Slavkovský les protected landscape area, western Bohemia, which occuring on mesic to wet soil. For this study an area surrounding Ovesné Kladruby hamlet was chosen. The aim of this thesis is to explore, which plant species can occur on the former fields and how the species composition and species diversity is effected by environmental and historical factors, such as soil properties, distance from an old grassland and the age of the field. I made 190 phytosociological relevés and noted 215 species of vascular plants. Some rare species were also present, e.g. an orchid Dactylorhiza majalis and state protected species Triglochin palustre. Species composition data were explored using multivariate analyses and species diversity data using linear regression. Species composition was effected mainly by soil properties. The effect of soil nitrogen and phosphorus content was the strongest one. Soil nitrogen content was positively correlated with soil moisture and on such localities mainly wetland...
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The Use of Multichannel Flow Cytometry in Biomedicine and Experimental Biology
Kideryová, Linda ; Smetana, Karel (advisor) ; Elleder, Milan (referee) ; Klíma, Jiří (referee)
Flow-cytometry is a process on which large numbers of single cells are quantitatively and qualitatively analyzed. This method gives information about size, granularity surface or intracellular markers of every single cell in suspension. In modern biology is worthy to perform quick, objective multiparametric analyses of cell phenotype. This project was focused on cells, which analyses are complicated by extreme rareness or lack of clearly identifying specific markers. Analysis of stromal cells of the investigated tumors (histiocytoma and tumor fibroblasts originating in squamous epithelium: basalioma (BCCF) and spinalioma (SCCF) elucidated alteration of gene expression induced by tumor cells. Tumor-derived stromal fibroblasts acquire distinct properties to shape a microenvironment conducive to altering the phenotypic characteristics of normal epithelial cells in vitro. Reproducible, quick and highly sensitive method of detection extremely rare non-haematopoetic cells (EPC, CEC) was established. Numbers of CFU-En correlate neither with circulating endothelial progenitors nor with matured endothelial cells detected by flowcytometry. These colonies are formed in cooperation of CD14 + and CD4+ cells. Numbers of endothelial progenitors and matured endothelial cells are closely related with vessel endothelium...
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Contentious issues of self-defence in Czech case law
Kabát, Robert ; Císařová, Dagmar (referee) ; Vokoun, Rudolf (advisor)
84 SUMMARY Controversial Issues of Necessary Defense in the Judicial Practice The main purpose of the thesis is to analyze necessary defense in Czech criminal law. Author's main focus is determined by the title of the thesis and he mainly concentrates on judicial practice. Nevertheless, substantial part of the thesis comprises comparison with jurisprudence. Only theory deals with some issues, these ones are included too. If it's needed, the author compares neces- sary defense with similar legal institutes in legislation of foreign countries or briefly describes historical evolution of important issues. The thesis is compound of six chapters. Chapter One includes introduction, explains starting points and approaches. First content chapter is chapter Two. It defines basic terminology used in the thesis: circumstances excluding criminal liability (i.e. defenses or excuse de- fenses), circumstances excluding lawlessness (i.e. justification defenses) and necessary defense (i.e. self-defense and defense of person, property or other legal interest protected by criminal law). Chapter Three contains the core of the thesis. It examines basic elements of necessary defenses and problems typically connected with particular elements. According to usual structure of papers on necessary defense, the chapter is...
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Golden nanoparticle in optical tweezers: influence of shape and orientation on optical trapping
Šiler, Martin ; Brzobohatý, Oto ; Chvátal, Lukáš ; Karásek, Vítězslav ; Paták, Aleš ; Pokorná, Zuzana ; Mika, Filip ; Zemánek, Pavel
Noble metal nanoparticles (NPs) have attracted increased attention in recent years due to various applications of resonant collective oscillations of free electrons excited with light (plasmon resonance). In contrast to bulk metal materials, where this plasmon resonance frequency depends only on the free electron number density, the optical response of gold and silver NPs can be tuned over the visible and near-infrared spectral region by the size and shape of the NP. Precise and remote placement and orientation of NPs inside cells or tissue would provide another degree of control for these applications. A single focused laser beam – optical tweezers – represents the most frequently used arrangement which provides threedimensional (3D) contact-less manipulation with dielectric objects or living cells ranging in size from tens of nanometers to tens of micrometers. It was believed that larger metal NPs behave as tiny mirrors that are pushed by the light beam radiative force along the direction of beam propagation, without a chance to be confined. However, recently several groups have reported successful optical trapping of gold and silver particles as large as 250 nm. We\noffer an explanation based on the fact that metal nanoparticles naturally occur in various nonspherical\nshapes, and their optical properties differ significantly due to changes in localized plasmon excitation.
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Optical spectroscopy of magnetic nanostructures
Lišková, Eva
Title: Optical spectroscopyof magnetic nanostructures Author: Eva Liskova Department: Fyzikalni Ostav Univerzity Karlovy Supervisor: Prof. Ing. Stefan Visnovsky, DrSc. Supervisor's e-mail address: visnov@karlov.mff,cuni.cz Abstract: Magnetic oxide nanostructures of La2/3Sri/3Mn03, BixYi.xFe5012 and Fe304 were investigated using magneto-optical reflection spectroscopic ellipsometry in the photon energy range between 1 and 5 eV. The samples were grown using MBE (Molecular Beam Epitaxy) and PLD (Pulsed Laser Deposition). Their spectroscopic studies were focused to the effects of growth conditions, substrate crystallographic orientation as well as those of subsequent heat treatment in oxygen. Thanks to this selective approach, largely eliminating substrate contribution, relevant information on physical properties of the low volume samples was obtained. Note that ordinary structural and magnetic metrologies suffer of reduced sensitivity due to the dominating effect of bulky substrates. The research was motivated by practical applications of the investigated nanostructures in spin electronics, reading high density magnetic disks, in nonreciprocal optoelectronics devices, magneto-optical light modulators, and megnetophotonic crystals. In addition, the physical properties of magnetite present interest for the use...
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Spacetimes with photon rockets
Kolář, Ivan ; Podolský, Jiří (advisor) ; Krtouš, Pavel (referee)
In this work we study exact spacetimes that represent the gravitational field of a localized object accelerating due to an anisotropic emission of photons - pho- ton rocket. First, we describe general properties of the Kinnersley and the Bonnor rocket, which both belong to the family of Robinson-Trautman spacetimes. Sub- sequently, we summarize two main approaches to the study of asymptotically flat spacetimes: the Bondi-Sachs and the Penrose methods, combined and modified by Tafel and Pukas in recent papers. We compare the mass aspect of the Robinson- Trautman spacetime obtained by both methods, and generalize thus the relation found by von der Gönna and Kramer. Next, we calculate the energy-momentum vector, the Bondi rest mass, and the "news tensor for the arbitrarily moving Kin- nersley rocket. By using these results, we naturally define the velocity vector of the rocket with respect to the Minkowski "background spacetime. We conclude with the physical interpretation of the Kinnersley rocket in various reference fra- mes.
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Stochastic Models with Sums Containing a Random Number of Random Variables
Vališ, Pavel ; Dostál, Petr (referee) ; Klebanov, Lev (advisor)
The thesis studies stochastic models with sums of a random number of random variables. It shows examples of such models including utilization in economics. It describes stable and v-stable distributions with conditions of their existence and with some their properties. Analogies of these distributions are introduced for discrete random variables and some properties and examples are given. Possible series representations of such distributions are mentioned. Analogies of the Law of Large Numbers and the Central Limit Theorem for a random number of random variables are also described.
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Licence agreement in the legal systems of the Czech Republic and England and Wales
Johanna, Tomáš ; Žikovská, Petra (advisor) ; Dobřichovský, Tomáš (referee)
The objective of this diploma thesis is to render a comprehensive analysis of licence contracts in two countries - the Czech Republic and England and Wales. The effort to highlight differences between the two scrutinized jurisdictions and related criticism are the most important methods applied in this work and, hopefully, the most recognizable benefits of it. The thesis consists of a short introduction, followed by four descriptive chapters and author's subjective conclusions. The introductory part presents methods of research used throughout the work and implicitly hints what can the reader except when studying this diploma thesis. The first chapter splits into two mutually linked subchapters. The first one defines the very term licence, its etymology and classification. The following subchapter describes general characteristics of intellectual property, a crucial topic to licence contracts and thus indirectly to this thesis. This thesis promises a comparison of two legal systems and the second chapter fulfils this aim. Consisting of two additionally divided subchapters, the author engages in an analysis of the copyright and patent law respectively. Both examined intellectual property rights are looked at via optics of Czech, British and European intellectual property law. After being...
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Slope stability calculations for small dams
Hajda, Jindřich ; Hodák,, Jiří (referee) ; Říha, Jaromír (advisor)
There are approximately 20 000 small dams in the Czech Republic. This number entails many ponds or small flood attenuation reservoirs, which provide protection against floods. We do not know much about the structure and material properties of these earth dikes. Concerning the small dam stability the current technical standard ČSN 75 2410 focuses foremost on the angle of both the upstream and downstream slopes in case of different materials, and the method of the stability assessment in case of a dam height being 6m or more. Most of these earth dikes are still standing in spite not being built according to any technical standards. They do not follow any standards mostly because they were built before the modern technical standards were published. This diploma thesis focuses on assigning the degree of a reserve in the safety factor for studies of 5 homogeneous earth dikes and 3 inhomogeneous earth dikes. The calculation was done using the Plaxis 2D software using to the shear strength reduction method. The Calculation of the safety degree is made for 4 typical load cases.
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EXPERIMENTAL STUDY OF PIB-BASED CVD GRAPHENE TRANSFER EFFICIENCY
Bouša, Milan ; Kalbáč, Martin ; Jirka, Ivan ; Kavan, Ladislav ; Frank, Otakar
The transfer of graphene prepared by Chemical Vapor Deposition (CVD) from metal catalyst to target substrate is an important step in preparing desirable nanoscale structures in various fields of science, and thus searching for fast, cheap and clean method attracts great interest. Investigation of mechanical properties of graphene, which are crucial for applications in flexible electronics, performed on bendable synthetic materials, requires a transfer technique using polymers soluble in aliphatic solvents harmless for target polymer substrates. In this study we explore a dry technique using polydimethylsiloxane (PDMS) as stamping polymer and polyisobutylene (PIB) layer as graphene-support polymer. After the transfer PDMS is peeled off and PIB is dissolved in hexane, hence this method fulfils the above mentioned prerequisite. The effectiveness of this transfer was examined by scanning electron microscopy, optical microscopy and Raman microspectroscopy including micro-mapping, and finally by X-ray photoelectron spectroscopy. With all methods carried out, it was found that this sort of stamp-technique is suitable for a high precision transfer of small grains of CVD graphene onto polymer substrates with large yields and similar purity compared to poly(methylmethacrylate) (PMMA)based transfer methods. However, it introduces substantial quantity of surface discontinuities, and therefore this is not a proper method for large scale applications.
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