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Study of factors influencing the function of MntH, membrane transport protein of E. coli
Jurková, Ingrid ; Urbánková, Eva (advisor) ; Krůšek, Jan (referee)
MntH belongs to the Nramp family of transport proteins, and plays an important role not only in homeostasis of iron and manganese, but also in bacterial defence against the immunity response of an infected host cell. MntH co-transports divalent metal ions into the cell together with protons with a stoichiometry dependent on the membrane potential and extracellular pH. Using the redistribution potential dye diS-C3(3), we measured the effects of MNTH expression and MntH-mediated metal transport on the cell membrane potential and intracellular pH. Cells expressing MNTH were found to be hyperpolarised and their membrane potential was depolarised upon the addition of metal ions. In the theoretical part of our work, we explored general four-, six-, and eight-state carrier models that were modified by introducing the voltage dependence of all rate constants. Using mathematical modelling, we simulated the effect of various model parameters (including membrane potential, substrate concentration, and carrier or substrate charge) on substrate influx. We observed some of the transport characteristics described for MntH proteins such as variable symport stoichiometry that is influenced by the membrane potential and pH. However, for a more detailed simulation of the eight-state carrier model, more information about...
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Principles of trading on betting exchanges
Karásek, Michal ; Málek, Jiří (advisor) ; Moravec, Lukáš (referee)
Unlike traditional stock exchanges, where bonds, shares and financial derivatives are traded, on the betting exchanges there are traded probabilistic estimates of the results of sporting or social events. The market price of bets, namely the market implied probability is influenced by estimate of the outcome. The specificity of betting exchanges is also a short period to maturity of contracts, and the possibility to trade with the estimated result of one real world event in several sub-markets simultaneously. In theoretical analysis, we have defined the bet, the underlying asset, and the binary betting contract, which is traded on betting exchanges. We have described some practical aspects of trading. Properties of the probabilistic contracts are demonstrated on several examples. Finally, we constructed the mathematical model of a tennis match, which is based on a binomial valuation model. This allows us to compare the market price of a contract with the price recommended by the model.
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Raymond Queneau and his novel Blue Flowers. Translation of one type of French experimental prose
Sauerová, Klaudia ; Belisová, Šárka (advisor) ; Šotolová, Jovanka (referee)
Raymond Queneau's novel s ha ve been translated in to Czech since the 60's of the 20th century. This work focuses on two of hi s novels, typical of their experimentalism: Zazie in the Metro and The Blue Flowers. A stylistic analysis of the original text showed different aspects of Queneau's poetics and also difficulties faced by a translator. Unusually rich means of expression, such as puns and neologisms at the lexical level, changing of stylistic layers or new French - handwriting created by the author to draw nearer spoken and written language, intertextuality and mathematical structures incorporated into the composition of the novel s are typ i cal features of Queneau' s work. We examined possibilities of Czech while translating Queneau's language experiments by comparing translations of two Queneau's novels, do ne by two different translators. Our work concentrates mainly on problems with translating puns, neologisms, phraseology, and new French. Jiri Pelikan 's trans lati on of the novel The Blue Flowers proved that in spite of some divergences between the original and the target text (archaization of verba dicendi, compensation), it is, on the whole, possible to keep to the author' s complex poetics, and to create, within the given scope, a work of translation that can compare with the original. The...
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Edukometrie - Item response theory
Voňková, Hana
Title: Measurement of Education - Item Response Theory Author: Hana Křížovská Department: Department of Probability and Mathematical Statistics Supervisor: Prof. Ing. František Fabian, CSc. Supervisors' e-mail address: he has not Abstract If we want to study abilities of certain pupils or other people in a given area, we can give them a didactial test, which would consist of items testing the abilities in question. The goal is then to determine the qualities of the people (ability parameter) and the relative difficulty of the questions (parameters of the questions) on the basis of the answers. Further we estimate how would a pupil, who have passed just one part of the test (assuming we have the item parameters of the whole test), would perform in the rest of the test. This is the research area of the Item Reponse Theory (IRT). In the introductory section the reasons are given for why we should use the IRT rather than the classical test theory for evaluating didactical test results, althought it's not regulary done in our country. The dichotomous Rasch model, which is one of the main IRT models, is described in detail. First the model is derived and then its main features presented. For the case of Rasch models we also demonstrate the most used methods of estimation of the ability and difficulty parameters....
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Tracking of axonal bundles in diffusion MRI brain images
Piskořová, Zuzana ; Vojtíšek, Lubomír (referee) ; Labounek, René (advisor)
The aim of this thesis is to design tracking algorithm which will be able to track white matter bundles in diffusion MRI data, this problem is called tractography. Tractography is feasible because specific profile of diffusion appears in white matter. The introduction to the topic includes summary of methods for estimation of diffusion profile and basic tracking algorithms. In this work diffusion tensor model (DTI) was used for estimation of diffusion profile. Based on the DTI, vector field characterizing direction of diffusion for every voxel was created. Combining vector field with seedpoint, we achieved task solvable by Euler or Runge-Kutta method. Termination criteria were established for maximum curvature of trajectory and minimum value of fractional anisotropy (FA). Algorithm was tested on mathematical and tractographical phantom before it was used on real biological data. The results of tracking on phantoms proved the funcionality of the algorithm. Expected error appeared in areas of crossing fibers, it is related to DTI model limitations. To solve problematic fibers characterized by seedpoint near the border of the fiber, FA-weighted trilinear interpolation was designed. Implementation of this algorithm, however, did not cause better results. The results of tracking on the real data were controversial. Tracking was performed on 5 healthy subjects and 4 anatomicaly specific tracts. The results were compared with tractographic atlas.
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Absoption in mathematics and orientation towards mathematics
Kmínková, Eliška ; Rendl, Miroslav (referee) ; Pavelková, Isabella (advisor)
In the beginning of my dissertation me and my supervisor set out several objectives. We concerned ourselves on incentives factores acting prejudice in favour of mathematics and incite orientations for mathematics as well. Various kinds of interests (individual, situational, actual, special-interest), achievement motivation, flow experience and perceived capability for mathematics. We prepared two various lessons of mathematics for the students in graduation class of gymnasium - the first one conventional, the second one experimental, alternative method. We concerned ourselves in students' preferences - which classwork is convenient to successful 1 sudents in mathematics and which one to students which go badly in maths. Next objectiv was observing the group of students "orientated on mathematis", preparing themselves for leaving examination in mathematics and preparing themselves for study in faculties where is this subject is one of the major. What influences the love for mathematics? Situation interest - we took of both from lessons comparison by the students and of their flow experience during lessons. Students' flow experience was almost similar in both lessons, though a little bit better flow experience had students in conventional lesson. The students has been enquired which kind of lesson was better...
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Stochastic models for genetic analysis
Selementová, Martina ; Zichová, Jitka (referee) ; Kulich, Michal (advisor)
Nazev prace: Slochasticke niodcly pro geneliekou analyzu Autor: MartinaSelementova Katedra: Katedra pravdepodobnosti a matematicke statistiky Vedouci bakalafske prace: Mgr. Michal Kulich, PhD, e-mail vedouciho: kuliclX^karlin.mff.cuni.cz Abstrakt: V pfedlozene praci studujerne elementarni stochasticke melody pro modelovani genetickych populaci. Nejprve uvadime zakladni pojmy obecne gcnetiky pro snadnejsi oricntaci v textu. V naslcdujicich kapitolach se zabyvame dynamikou vyvoje populace a zakladnimi problemy vyberu v populaci. lllavnim tcmatem je nahodne kfizeni v populaci, ktcre dale aplikujeme na pohlavne va/ane geny, letraploidy. autosterilizacni geny a na pfi'pad dvou lokusu. Ve druhe casti se xabyvame problemy vybcru: zamC'fili jsme se pf-edevsim na vyber xalozeny na gcnolypu aplikovany na pohlavi a pohlavne vazane geny a dale na lamiliarni vyber a konkretnf pn'klad Rh faktoru. Klicova slova: nahodne kfizeni, vyber Title: Stochastic Models for Genetic Analysis Author: Martina Selementova Department: Department oi'Probability and Mathematical Statistics Supervisor: Mgr. Michal Kulich, PhD. Supervisor's e-mail adress: kulich(«)karlin.mff.cuni.cz Abstract: In the presented work we study elementary stochastic methods for modeling genetic populations. First we show some basic notion of general genetics for...
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Rezonanční frekvence generátorů syntetizovaných proudů
Kordík, Jozef ; Trávníček, Zdeněk ; Šafařík, P.
This contribution focuses on axisymmetric synthetic jet actuators from the theoretical point of view. In order to evaluate their resonance frequencies, four mathematical models were derived. The results were compared with experimental data, and analyzed. With respect to the theoretical and experimental results, the applicability and limits of the models were discussed. The results illustratively prove correctness of the previous derivation based on transformation of mechanical energy.
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Cardiovascular involvement in patients with Fabry disease
Jirák, Daniel ; Hájek, Milan (advisor) ; Vymazal, Josef (referee) ; Žižka, Jan (referee)
The evaluation of clinical magnetic resonance (MR) images is influenced by errors (subjective evaluation, noise, etc.). It is possible to eliminate these errors by using certain mathematical and statistical methods. One of these methods is texture analysis (TA), which can describe images quantitatively by computed texture parameters. The aim of this thesis was to analyze MR images of various subjects (phantoms, apples, calf muscles, livers) by TA and to evaluate its possible use in clinical practice. The main tasks of the thesis were: 1) to develop a new phantom suitable for TA and MR imaging that is biochemically and mechanically stable 2) to optimize an algorithm for TA parameter selection and classification 3) to apply TA in evaluating MR images. The first methodical part of the thesis deals with the optimization of texture parameter selection and texture classification. For this purpose a new type of phantom was developed. This PSAG phantom, with a nodular structure from polystyrene spheres (PS) placed into agar (AG), is suitable for MR imaging and for TA because it produces a strong MR signal and because its T1 and T2 relaxation times are in the range of biological tissue and can be easily modified by employing various densities of PS spheres or by the addition of a contrast agent. Measurements of PSAG...
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