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STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
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Parallel single-cell analysis of active caspase-3/7 in apoptotic and non-apoptotic cells
Ledvina, Vojtěch ; Klepárník, Karel
Caspases are proteases that play key role in the process of apoptosis, the programmed\ncell death. Among them, caspase-3 and -7 are main executioner caspases that cleave\nmany vital proteins during apoptosis and after their widespread activation, the process\ncannot be reversed. To analyze caspase-3/7 activation within single cells, a miniaturized\ndevice for parallel analysis of eight samples was developed. The assay is based on the\nmodified luciferin-firefly luciferase bioluminescence (BL) system. Individual\nsuspended cells were collected and transferred into detection microvials using a\nmicromanipulator. The bioluminescence was detected using a photon counting head\nwith cooled photcathode. The LOD suitable for detection of active caspase-3/7 in both\napoptotic and non-apoptotic cells was reached.
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The Tax Assignation and Theater
Gerneš, David ; POKORNÝ, Jiří (advisor) ; VÁVROVÁ, Hana (referee)
Bachelor thesis aims based on an analysis support system theaters in the Czech Republic, the analysis of the tax system in the Czech Republic and analysis of tax assignations in the Slovak Republic, to investigate whether for the Czech theater network, this measure was beneficial and whether it would be worth it to deal with its introduction into practice. The thesis also examines the impact of the introduction of the assignation of income tax on Czech public budgets and polls. Within the survey sent to 120 respondents who were asked about their relationship to culture and whether they would be introducing a possibility for assignations and what area non-profit sector would contribute. On the basis of these steps is then designed a system of assignations suitable for Czech Republic.
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Cut Languages in Rational Bases
Šíma, Jiří ; Savický, Petr
We introduce a so-called cut language which contains the representations of numbers in a rational base that are less than a given threshold. The cut languages can be used to refine the analysis of neural net models between integer and rational weights. We prove a necessary and sufficient condition when a cut language is regular, which is based on the concept of a quasi-periodic power series. We show that any cut language with a rational threshold is context-sensitive while examples of non-context-free cut languages are presented.
Fulltext: content.csg -  PDF
Plný tet: v1236-16 - PDF
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Natural houses in gardens
Formánková, Kristýna ; Kunt, Miroslav (advisor)
Thesis discusses natural houses which are supposed to be part of our lives in the future. These houses may be for someone and they might prefer smarter building with non-recyclable materials when choosing a new housing. But it is necessary to think about our future and sustainable development. We also need to tell ourselves what is really a priority for our planet. There comes a time when they will prefer building materials which can be used somehow after some time or be recycled. This is related to the design of the garden. It is designed to fulfil an ornamental, economic and social function. The garden is an integral part of each house, therefore it is important for each element used to be creating the garden as a linked harmonious whole. The study deals with the concept of a natural houses home in accordance with the maximum use of the garden.
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Population genetic analysis of Old Kladruber horse
Vostrá Vydrová, Hana ; Majzlík, Ivan (advisor) ; Karel, Karel (referee)
The Old Kladruber horse, along with the Lipizzaner horse, Andalusian horse and Lusitano horse, is of the original Italo-Spanish type. The Old Kladruber horse is kept in two colour varieties (grey and black). Because the population is closed, there is a concern about the loss of genetic variation. The genetic diversity and population structure were analysed in the Old Kladruber horse breed based on the pedigree information of animals that were registered in the Studbook to identify factors that may have affected the genetic variability of the breed. Pedigree records collected from 1729 to 2013 contained information on 7971 animals that were used in the analyses. The pedigree depth was up to 33 generations, with an average of 15.1 complete generations. The effective number of founders and ancestors contributing to the current genetic pool was 92.69 and 17.16, respectively. The average values of the inbreeding coefficient were as follows: 13% (with a maximum value of 29%) for the reference population (individuals that can currently take part in reproduction, n=612), 11% for the grey variety (with a maximum value of 25%) and 15% for the black variety (with a maximum value of 29%). The proportion of inbred animals was high (99%). The average rate of inbreeding in the reference population was 1%: 0.8% for the grey variety and 1.1% for the black variety, and the respective estimates of the effective population sizes were 52 for the reference population, 62 for the grey variety and 45 for the black variety. The estimated percentage of genetic diversity lost due to non-random mating within subpopulations and the reference population was 1.0, 1.0 and 1.2%, respectively. The total loss of genetic diversity in the reference population, in the grey variety and in the black variety was 11%, 13% and 17%, respectively.
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Non-invasive methods for sex and steroid homones determination in gibbons of the genus Nomascus
Bolechová, Petra ; Bartoš, Luděk (advisor) ; Pavel, Pavel (referee)
The gibbon primates of the family Nomascus are classified as critically endangered species, and, to date, basic understanding and information about their biology is missing. With regard to the status of these animals in the wild and captive populations in zoos, being familiar with their reproduction, may improve captive breeding programs. Data collection in this study was to be carried out by the practical use of non-invasive methods (polymerase chain reaction for DNA extraction and enzyme immunoassays), using faecal samples for analysis. The first method, polymerase chain reaction, was used for sex determination in juveniles, because of their coat colour and visual similarity of secondary sex characteristic in both sexes; it is not possible to determinate sex without handling the animal. Another main purpose of this study is to try and answer the hypothesis regarding the ovarian cycle of females, factors influencing their hormone concentration and also the onset of sexual maturity in females and the timing of their fur colour change. Hypotheses were checked by monitoring the concentration of progesterone and oestrogen faecal metabolites and by evaluation of the composition of breeding groups of gibbons with the ZOO influence. During a four year period (from 2010 till 2014), there were a total of 51 animals analysed from 16 different zoos with a faecal sample count totalling 1618 samples. The results confirmed the use of noninvasive methods for sex determination, and thus ensuring the maximum welfare standards. Endocrinological analysis confirmed the hypothesis of the influence of the environment (ZOO) to the hormone concentrations and female´s pregnancy effect in conjunction with her age on the final results of the male - father hormone concentrations. The initial information in this study is the confirmation of the onset of ovarian cycle in young females without connection to their fur colour change and a significant factor of a mother´s impact and her territoriality. This study is the first to present a long term monitoring of ovarian cycles in females and hormone concentrations of other individuals, both male and female, and from various age groups. The results allow us to understand the possible impact of zoo environments on the reproductive status of these gibbons and contribute to the general improvement of breeding management.
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Corrosion behavior of plasma coatings CuAl10 and CuAl50 on magnesium alloy AZ 91
Kubatík, Tomáš František ; Stoulil, J. ; Stehlíková, K. ; Slepička, P. ; Janata, Marek
The most common magnesium alloy AZ 91 is widely used as a structural material, but its use is limited at higher temperatures and high humidity. Plasma spraying is a technology that allows to prepare protective metallic and non-metallic coatings on a wide variety of substrates including magnesium and its alloys. In this study, CuAl10 and CuAl50 were plasma sprayed on magnesium alloy AZ 91 with the aim to study corrosion resistance of the plasma sprayed coatings. The corrosion resistance of layers was evaluated by the method of electrochemical potentiodynamic measurement as well as long-term corrosion tests in a condensation chamber with 0.5 mol\nNaCl at the temperature of 35 °C for 1344 hours. Layers with 1, 2, 5 passes and passes of CuAl10 with the thickness ranging from 75 to 716 mm and CuAl50 with the thickness ranging from 64 to 566 mm were prepared. The increased corrosion velocity was observed in the case of thin layers of 2 and 5 passes due to the development of a galvanic corrosion couple. The CuAl10 layer prepared with ten passes has an outstanding corrosion resistance.
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Stability and convergence of numerical computations
Sehnalová, Pavla ; Dalík, Josef (referee) ; Horová, Ivana (referee) ; Kunovský, Jiří (advisor)
Tato disertační práce se zabývá analýzou stability a konvergence klasických numerických metod pro řešení obyčejných diferenciálních rovnic. Jsou představeny klasické jednokrokové metody, jako je Eulerova metoda, Runge-Kuttovy metody a nepříliš známá, ale rychlá a přesná metoda Taylorovy řady. V práci uvažujeme zobecnění jednokrokových metod do vícekrokových metod, jako jsou Adamsovy metody, a jejich implementaci ve dvojicích prediktor-korektor. Dále uvádíme generalizaci do vícekrokových metod vyšších derivací, jako jsou např. Obreshkovovy metody. Dvojice prediktor-korektor jsou často implementovány v kombinacích modů, v práci uvažujeme tzv. módy PEC a PECE. Hlavním cílem a přínosem této práce je nová metoda čtvrtého řádu, která se skládá z dvoukrokového prediktoru a jednokrokového korektoru, jejichž formule využívají druhých derivací. V práci je diskutována Nordsieckova reprezentace, algoritmus pro výběr proměnlivého integračního kroku nebo odhad lokálních a globálních chyb. Navržený přístup je vhodně upraven pro použití proměnlivého integračního kroku s přístupe vyšších derivací. Uvádíme srovnání s klasickými metodami a provedené experimenty pro lineární a nelineární problémy.
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Extensions to Probabilistic Linear Discriminant Analysis for Speaker Recognition
Plchot, Oldřich ; Fousek, Petr (referee) ; McCree,, Alan (referee) ; Burget, Lukáš (advisor)
Tato práce se zabývá pravděpodobnostními modely pro automatické rozpoznávání řečníka. Podrobně analyzuje zejména pravděpodobnostní lineární diskriminační analýzu (PLDA), která modeluje nízkodimenzionální reprezentace promluv ve formě \acronym{i--vektorů}. Práce navrhuje dvě rozšíření v současnosti požívaného PLDA modelu. Nově navržený PLDA model s plným posteriorním rozložením modeluje neurčitost při generování i--vektorů. Práce také navrhuje nový diskriminativní přístup k trénování systému pro verifikaci řečníka, který je založený na PLDA. Pokud srovnáváme původní PLDA s modelem rozšířeným o modelování neurčitosti i--vektorů, výsledky dosažené s rozšířeným modelem dosahují až 20% relativního zlepšení při testech s krátkými nahrávkami. Pro delší testovací segmenty (více než jedna minuta) je zisk v přesnosti menší, nicméně přesnost nového modelu není nikdy menší než přesnost výchozího systému. Trénovací data jsou ale obvykle dostupná ve formě dostatečně dlouhých segmentů, proto v těchto případech použití nového modelu neposkytuje žádné výhody při trénování. Při trénování může být použit původní PLDA model a jeho rozšířená verze může být využita pro získání skóre v případě, kdy se bude provádět testování na krátkých segmentech řeči. Diskriminativní model je založen na klasifikaci dvojic i--vektorů do dvou tříd představujících oprávněný a neoprávněný soud (target a non-target trial). Funkcionální forma pro získání skóre pro každý pár je odvozena z PLDA a trénování je založeno na logistické regresi, která minimalizuje vzájemnou entropii mezi správným označením všech soudů a pravděpodobnostním označením soudů, které navrhuje systém. Výsledky dosažené s diskriminativně trénovaným klasifikátorem jsou podobné výsledkům generativního PLDA, ale diskriminativní systém prokazuje schopnost produkovat lépe kalibrované skóre. Tato schopnost vede k lepší skutečné přesnosti na neviděné evaluační sadě, což je důležitá vlastnost pro reálné použití.
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