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Speciation rate
Leščinskij, Artem ; Storch, David (advisor) ; Macháč, Antonín (referee)
Speciation rate is a frequency at which an original species splits into two species per unit of time. Since this rate cannot be directly determined, it must be inferred from the fossil record or a reconstructed phylogeny using appropriate diversification model or nodes and branches of a phylogenetic tree. The homogeneous birth-death process is the basic method upon which other models, such as time-dependent or density-dependent models, are based. Non-model methods such as DR statistics, node-density metrics or inverstion length of terminal branches, are methods depend on reconstructed phylogenetic trees. More complex methods include MEDUSA, BAMM, CLaDS, MTBD, or trait-dependant models. Protracted-speciation models are biologically more plausible and describe speciation as a gradual process. These methods can detect more complex diversification regimes. Tip rate determines expected species-specific rate of speciation and is less dependent on the rates of extinction and diversification; rather, it corresponds to the rate of speciation. Model identifiability is a fundamental problem limiting the estimation of the speciation rate, but this limitation can be partially overcome by new techniques such as pulled rates. Keywords: speciation rate, phylogeny, diversification, evolution, model
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Interdependence obchodních vztahů mezi Austrálií a Čínou
Kluchová, Monika
The area of interest of this diploma thesis is the interdependence of trade relations between Australia and China. The diploma thesis is divided into a theoretical and a practical part. The heoretical part of the thesis consists of two main parts. The first part deals with the topic of the world economy and the tendencies that constantly affect it. The second part discusses foreign trade, its basic forms, development and selected theories of foreign trade. At first, the practical part deals with a brief assessment of the development of the economy and foreign trade of Australia and China. Subsequently, an analysis of trade relations between Australia and China, especially in the years 1995-2021, is made. Then, the degree of trade dependence of these relationships is evaluated. This thesis will also point to the development of territorial and commodity specialization or diversification of both countries. The last part of the thesis discusses the development of the position of the European Union as a trading partner of Australia.
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Ekonomické hodnotenie činnosti malej rodinnej farmy a návrh ďalšieho rozvoja
Matejovič, Branislav
Matejovič, B., Economic evaluation of the activity of a small family farm and a proposal for further development. Thesis. Brno 2023 The content of the thesis is to describe and evaluate the economic situation of the small family farm Cornland s.r.o. and process a proposal for the further development of its activity. In the literary research, an overview of the current situation, political strategies, the importance and specifics of small family farms and the importance of strategic management and strategic decision-making are summarized. The part of the own work summarizes the characteristics of the company Cornland S.r.o., the analysis of the company's management, the structure and development of the company's assets, the development of the economic result, the structure of costs and revenues. On the basis of the previous analyses, a SWOT analysis was made, strategies were proposed and a draft of measures for the strategic development of the company was drawn up. In the end, the main results were summarized
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Evolution of Host Specialisation, Phylogeography and Taxonomic Revision of Xenidae (Strepsitera)
Benda, Daniel ; Straka, Jakub (advisor) ; Malenovský, Igor (referee) ; Cook, Jerry L. (referee)
Twisted-winged parasites (Strepsiptera: Xenidae) are an excellent group for studying the specialisation of parasites on hosts. Their parasitic lifestyle led to the evolution of numerous morphological, behavioural, physiological, and reproductive adaptations. Moreover, many complex adaptive traits of Strepsiptera have no parallel in other organisms. In contrast, little attention has been paid to the study of strepsipteran molecular phylogeny, phylogeography, species delimitation, and their implications for taxonomic classification. Using the methods of molecular phylogeny, we created the first dated phylogenetic study of the family Xenidae. By investigating historical biogeography and ancestral host groups, we indicate that multiple lineages were exchanged between the New World and the Old World + Australia until Antarctica became completely frozen over. During the late Paleogene and Neogene periods, several lineages spread from the Afrotropics to other Old World regions and Australia. The original hosts of Xenidae were most likely social wasps, and the subsequent host switch from social to solitary wasps was secondary and probably occurred only once. The parallel host switch from solitary wasps to digger wasps (Sphecidae) occurred independently in the New and Old World. The biogeography and...
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Comprehensive analysis of putrescine metabolism in A thaliana using GWAS, genetic risk score, metabolic modelling and data mining
Schwarzerová, Jana ; Bartoň, Vojtěch ; Walther, Dirk ; Weckwerth, Wolfram
Polyamines are known to be functionally involvedin plant responses to stress conditions. Despite a large amount ofphysiological and genetic data, the mode of action of polyamines,especially putrescine, at the molecular level still remains unclear.An increasing number of studies point to a role of putrescine instress defense of plants due to influencing the formation of reactiveoxygen species (ROS) in cellular stress conditions. Moreover,putrescine has been found to modulate abscisic acid (ABA)biosynthesis at the transcriptional level in response to lowtemperature, revealing a novel mode of action of polyamines asregulators of hormone biosynthesis. This study presents a newholistic approach towards the analysis of putrescine metabolismusing genome-wide association studies and the calculation ofgenetic risk scores extended by Boolean analysis in metabolitesnetwork as well as data mining from available databases andliterature. It can lead to a better understanding of biologicalprocesses involved in adaptation of plants to environmentalchanges.
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The investment portfolio and its creation
Čermák, Jan ; Luňáček, Jiří (referee) ; Dohnal, Mirko (advisor)
The subject of the diploma thesis is the proposal of a sector-diversified investment portfolio of American value stocks for the use of an ETF fund. The thesis consists of three parts. In the first part, the necessary theoretical background is explained, on the basis of which the criteria for the selection of stock titles are determined. In the following part the fundamental analysis of selected stock titles is presented. The conclusion of the work is the proposal of a stock portfolio based on an investment recommendation and determination of the percentage representation of individual stock titles.
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Portfolio diversification
ČERNÝ, Oldřich
The work deals with the diversification of the stock portfolio. Diversification is the di-vision of the portfolio into different investment instruments, into companies from different fields in different countries. The data was drawn from https://finance.yahoo.com. The companies on the market we-re selected using stock screening, according to several recommended criteria (price / profit ratio, price / book ratio, current ratio, debt to equity, market capitalization, region). Screener selected 26 companies, from which the final 10 companies were selected. For selected compa-nies, data for the last 5 years were downloaded from the monthly closing prices of shares from 1 March 2016 to 1 March 2021. First, the monthly and annual returns and risk of individual shares were calculated. Subsequently, the monthly return on the portfolio was calculated with a weight of 10% for each action. To calculate the risk of the portfolio portfolio, it was necessary to calculate the covariance and the correlation coefficient. Finally, the MS Excel solver was used, which looks for the minimum and maximum value. When using this add-on, it was necessary to specify restrictive calculation criteria. The sum of the weights of individual shares must be equal to 100%, it must be positive and calculated with the minimum risk at the given return, or the highest return with the given risk. The solver determines the portfolio with the lowest risk and the highest return, which will form the upper and lower limit of the allowable portfolios. The researcher also counts on 15 portfolios with the maximum return and the given risk. The risk was calculated from the lower limit to the upper one by one percent. The investor decides for each portfolio that meets his risk and return requirements. Whether he prefers a high return with a given level of risk, or a low risk with a given rate of return.
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Portfolio diversification
KOVANDOVÁ, Klára
This bachelor's thesis follows up the impact diversification on return and risk of investment portfolio of securities. The main goal of this thesis is assessing portfolios using the Markowitz Portfolio model. Ten companies operating in various market segments and traded on the New York Stock Exchange were selected for assessment. Ten randomly chosen companies traded on New York Stock Exchange were analysed during their operating period from January 1, 2015 to December 31, 2019. The main factors that lead to the determination of optimal portfolio were identified. At first, the historical rates of return and historical values of risk of individual companies were calculated. Furthermore, the values of covariance, correlation and return, and portfolio level of risk were determined. The highest value of risk was 8.24% with a value of return value 2.21% p.m. The lowest value of portfolio risk was 2.79% with a value of return 0.90% p.m. Finally, the efficient frontier was determined. It shows all the optimal portfolios that would offer the highest expected rate of return for a given level of risk or the lowest risk for a given level of expected return.
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Investing in Commodities through Futures Contracts
Králík, Patrik ; Bílek, Michael (referee) ; Rejnuš, Oldřich (advisor)
The diploma thesis focuses on the analysis and comparison of selected commodities in order to create an investment recommendation to diversify the hedge fund's equity portfolio. The theoretical part deals with issues related to the investment portfolio, commodities, trading through futures contracts and explains the applied analytical methods. In the practical part, commodities are first selected, which are then analyzed by selected methods and finally compared by a comparative method. The last part of the work contains, based on the results, a proposal to expand the investment portfolio and the process of making investments through commodity futures contracts.
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