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Trade-off between egg size and number at the level of bird families
Špaldoňová, Alexandra ; Hořák, David (advisor) ; Reif, Jiří (referee)
Trade-off between offspring size and number belongs to the most discussed concepts in the life history theory. The aim of this study was to elucidate the relationship between egg size, clutch size and female body mass at the family level in bird's and to examine whether there is the relationship between offspring size and number and life history traits specific for particular bird families. From published sources, I collected data about 5.073 species belong in 146 families. Most species of birds lay smaller clutches, on average three eggs. In 112 families from 130 tested eggs size was positively correlated with female body mass. There is evidence that egg size and clutch size are inversely related in 83 families from 130 tested but only for 34 families was significant. The relationship exists independently of female body mass across bird families and this suggests a trade-off between these traits. The relationship between the strength and shape of egg size-number correlations and life history characteristics of bird families was not frequent. According to results, the strength of correlation seems to be related to development mode and diet type. The negative egg size-number correlation is stronger when incubation period and fledging time is longer and in birds with longer lifespan. The...
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Role of heat shock proteins in the pathogenesis of leukaemia
Kopřivová, Olga ; Hromadníková, Ilona (advisor) ; Černá, Marie (referee)
(Abstract) Some of heat shock proteins (Hsp), for example the inducible form Hsp70, are expressed on the surface of tumour cells. High Hsp expression is reflected in tumour cell features, such as ability to progression, to metastasize and resistance to apoptosis. The question is whether Hsp gene expression correlates with surface expression. The aim of this master thesis is to compare surface and gene expression of Hsp70 and observe the gene expression of some other Hsp proteins (Hsp27, Hsp60, Hsp90 and HspBP1) in leukaemia. The research was carried out on cell lines obtained from leukaemic blasts of patients with acute myeloid leukaemia: UoC-M1, HL-60, OCI/AML3, THP-1, HU-3 and TF-1 that had been cultivated in vitro. Hsp70 surface expression was detected using flow cytometry, and gene expression of each Hsp was studied using real-time RT-PCR. It was found out that high surface expression of Hsp70 did not correlate with gene expression in consequence of negative feedback applied in Hsp expression regulation. Hsp27 gene expression was increased compared to negative (healthy) control on all tumour cell lines, with the highest increase on the THP-1 line. Hsp60 gene expression was increased compared to negative (healthy) control on all tumour cell lines and there were not remarkable differences in...
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Phytoplankton of the Tatra lakes: factors influencing taxonomic composition and biomass
Červenková, Lenka ; Nedbalová, Linda (advisor) ; Štefková, Elena (referee)
The aim of this diploma thesis was to describe species composition and biomass of phytoplankton in the Tatra Mountains lakes (Slovakia, Poland) and environmental factors influencing them. The surface layer of 89 lakes was sampled in September 2004. Flagellates from Chrysophyta, Dinophyta and Cryptophyta most frequently dominated the phytoplankton biomass. Lake in the same valley usually differed in their dominant taxonomic group as a result of different lake morphometry, catchment type and detailed geological structure. Based on the level of phytoplankton biovolume, the majority of lakes were ultraoligotrophic and oligotrophic, however, mesotrophic and even eutrophic conditions were recorded in some forest and meadow lakes. An allometric relationship between phytoplankton biomass and chlorophyll a was revealed. Specific chlorophyll content did not differ among taxonomic groups. Altogether 233 species were determined, the most diverse group were Chlorophyta. Species richness of lake was 3-46 and it was negatively correlated with altitude and positively correlated with lake area. The majority of species were rare both in term of biomass and number of lakes occupied by a particular species. Average local species biomass was positively correlated with regional distribution. The similarity of species...
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Symbolické reprezentace kompaktních prostorů
Kazda, Alexandr
Title: Symbolic representations of compact spaces Author: Alexandr Kazda Department: Department of Algebra Supervisor: Prof. RNDr. Petr Kůrka, CSc. Supervisor's e-mail address: kurka@cts.cuni.cz Abstract: The thesis concerns itself with Möbius number systems. These systems represent points using sequences of Möbius transformations. We are mainly inter- ested in representing the unit circle (which is equivalent to representing R ∪ {∞}). The main aim of the thesis is to improve already known tools for proving that a given subshift-iterative system pair is in fact a Möbius number system. We also study the existence problem: How to describe iterative systems resp. subshifts for which there exists a subshift resp. iterative system such that the resulting pair forms a Möbius number system. While we were unable to provide a complete answer to this question, we present both positive and negative partial results. As Möbius number systems are also subshifts, we can ask when a given Möbius number system is sofic. We give this problem a short treatment at the end of our thesis. Keywords: Möbius transformation, numeral system, subshift
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Zeemanův jev v polovodičových kvantových strukturách
Stráský, Josef ; Grill, Roman (advisor) ; Výborný, Karel (referee)
This theoretical thesis presents detailed study of negatively charged excitons - trions - confined in single quantum well in presence of perpendicular magnetic field. Complex valence band of GaAs/GaAlAs compound is described within Luttinger Hamiltonian framework. Singlet and triplet states of negative trion are introduced. Advanced theoretical analysis of Zeeman effect for different states of trion is performed. Landau gauge of magnetic field and unusual wavefunctions basis is chosen and its accuracy is tested. Evolution of ground state energy and photoluminescence spectra with magnetic field is evaluated for different values of Landé g-factors. Probability of occurrence of electrons with respect to the hole position and their spatial correlation function are investigated.
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Constraint satisfaction for inductive logic programming
Chovanec, Andrej ; Barták, Roman (advisor) ; Železný, Filip (referee)
Inductive logic programming is a discipline investigating invention of clausal theories from observed examples such that for given evidence and background knowledge we are finding a hypothesis covering all positive examples and excluding all negative ones. In this thesis we extend an existing work on template consistency to general consistency. We present a three-phase algorithm DeMeR decomposing the original problem into smaller subtasks, merging all subsolutions together yielding a complete solution and finally refining the result in order to get a compact final hypothesis. Furthermore, we focus on a method how each individual subtask is solved and we introduce a generate-and-test method based on the probabilistic history-driven approach for this purpose. We analyze each stage of the proposed algorithms and demonstrate its impact on a runtime and a hypothesis structure. In particular, we show that the first phase of the algorithm concentrates on solving the problem quickly at the cost of longer solutions whereas the other phases refine these solutions into an admissible form. Finally, we prove that our technique outperforms other algorithms by comparing its results for identifying common structures in random graphs to existing systems.
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Jak velikost habitatu ovlivňuje společenstvo koprofilního hmyzu?
ZÍTEK, Tomáš
The effect of dung pat size on structure of dung inhabiting insect community was studied in Central Europe. Specifically all insect inhabiting the dung pat was targeted including both beetle and fly families. Abundance and species richness were positively correlated with increasing habitat volume. Density was negatively correlated with habitat size which represents low density refugee effect. Temporally co-occurring species which utilize the resource in similar way were separated by preferences for different habitat volumes.
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Effective corporate income tax rates of selected companies
Hladká, Jana ; Kubátová, Květa (advisor) ; Čuříková, Hana (referee)
This thesis analyzes an impact of a company size to its effective tax rate. Back looking microeconomics principle is used for the analysis. A dependence of the effective tax rate and company size measured by the employee headcount is verified for the segment NACE 23 in the Czech Republic for the period 2003 -- 2012 in the thesis. The dependency is proved by a negative correlation between the effective tax rate and the company size. The thesis contains also the analysis of historical development of relevant sections of the Czech Income Taxes Act. An impact of particular items adjusting accounting profit or loss to the tax base is analyzed through an alternation coefficient. The alternation coefficient is calculated on the accounting/tax items of the particular company operating in segment NACE 23.
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Does European Union and national regional policy correlate with a decrease in unemployment rate in Romania?
Gorda, Diana ; Ševčíková, Michaela (advisor) ; Prokop, Jaromír (referee)
The bachelor thesis aims at answering the question if the regional and European Union Cohesion policy correlates with a decrease in unemployment rate in Romania. The thesis starts the analysis with a controversial theoretical background, including the convergence and divergence views and the related economic theories, as Solow and AK models. The study proceeds to a short description of the Cohesion Policy, its funds and targeted aims. The bachelor thesis then analyses the challenges of the Romanian labor market, the reasons that bring to a non-competitive labor environment, and further on focuses on the vulnerable groups of population most affected by unemployment. At the same time, at this section the paper provides a final distinction between two time horizons: before joining and after joining the European Union. The last part of the research is composed of an empirical work concerning Cohesion policy funding and the effectiveness on a macroeconomic indicator, as unemployment. The correlation between unemployment rate and Cohesion Policy is found to be negative, as expected from the theoretical background.
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Assessment of hedge fund replication strategies
Kollár, Martin ; Dědek, Oldřich (advisor) ; Derviz, Alexis (referee)
Hedge funds are investment vehicles that provide solid risk-adjusted performance in various stages of market cycle and that are not strongly correlated to the markets they transact in. The profits from hedge funds were for a long time available only to high net-worth individuals or institutional investors, who could bear the possible negative effects of a serious downturn of the fund. The recent development in the hedge fund industry however leans toward the exploitation of hedge fund returns by a wider range of investors. Many hedge fund databases and investment banks have thus created different hedge fund indices and hedge fund clones that would replicate the exposures of hedge funds with smaller fees and smaller investment requirements. Our analysis showed that the development of such products has advanced into more promising stages, when new approaches are used to better replicate the hedge fund returns. Powered by TCPDF (www.tcpdf.org)
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