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The Study of Dynamic Behaviour and Interactions During the Temperature-Induced Phase Separation in Polymer Solutions
Kouřilová, Hana ; Hanyková, Lenka (advisor) ; Štěpánková, Helena (referee) ; Dušková - Smrčková, Miroslava (referee)
Title: The Study of Dynamic Behaviour and Interactions During the Tempera- ture-Induced Phase Separation in Polymer Solutions Author: Hana Kouřilová Department / Institute: Charles University in Prague, Faculty of Mathemat- ics and Physics, Department of Macromolecular Physics Supervisor of the doctoral thesis: doc. RNDr. Lenka Hanyková, Dr. Abstract: 1 H and 13 C high-resolution NMR spectroscopies were used for the phase separation investigation in three types of polymer solutions: i) poly(N -isopropylmethacrylamide)/D2O/ethanol with or without negatively charged comonomer sodium methacrylate, ii) random copolymers poly(N -isopro- pylmethacrylamide-co-acrylamide) in D2O, D2O/ethanol and D2O/acetone and iii) D2O solutions of polymer mixtures poly(N -isopropylmethacrylamide)/poly(N - vinylcaprolactam). For i) cononsolvency effect and influence of temperature on the phase separation was studied. Differences between mesoglobules formed as a consequence of cononsolvency effect and of temperature were found. While inside the cononsolvency-induced mesoglobules no bound ethanol molecules were detect- ed, in the mesoglobules formed by the effect of temperature ethanol molecules were present. The charge introduced into the polymer chains strenghtens polymer- solvent interactions. For ii) mesoglobules were found to be...
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Study of Cobaltites and Manganites by NMR and EXAFS
Procházka, Vít ; Štěpánková, Helena (advisor) ; Novák, Pavel (referee) ; Figiel, Henryk (referee)
This Thesis is devoted to a study of physical properties of manganites and cobaltites with perovskite structure. Combination of macroscopic (magnetization measurements and X-ray powder diraction) and microscopic (NMR and EXAFS) methods was applied in order to get a complex and detailed view on the charge and magnetic ordering of transition metals ions in the LaMn1xCoxO3 solid solutions. The Thesis presents new results which were published in international journals. The main result is the determination of details of Mn and Co local environments and the spin arrangement of their individual oxidation states in the ferrimagnetic structure of the compounds studied.
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The impact of working memory training on fluid intelligence in young-old adults
Štěpánková, Hana ; Niederlová, Markéta (advisor) ; Holmerová, Iva (referee) ; Smolík, Filip (referee)
Description and explanation of a natural decline of cognitive functions during ontogenetic aging laid in a century of its history grounds for various experiments trying to find wals to slow down or revoke theis process of decline. One of the cognitive domains that has been gaining ever stronger attention among neuroscientists is working memory, which is interconnected with other functions, especially with attention, executive function and fluid intelligence. So far, there has not been reached a consensus regarding a model of working memory. Nevertheless, there are many efforts to describe it, to explain its role within cognitive processes, and to enhance performance. They resulted in various complex and also specialized interventions that are used also in studies focused on older persons. This study adds to the body of literature on transfer effects of working memory training in young-old persons (age 65-75 years; N=65). It is a randomized controlled study with 2 intervened and 1 passive control groups. The goal was to find about an effect of different numbers of training lessons (10 or 20 in 5 weeks) with a computer-based adaptive visually presented verbal n-back, on latent variables of working memory and fluid intelligence. The results showed an ability of older people to significantly improve their...
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MR spectroscopy in patients with diabetes mellitus
Šedivý, Petr ; Štěpánková, Helena (advisor) ; Roztočil, Karel (referee)
This thesis deals with in vivo MR spectroscopy. Measurements in this thesis were performed on whole-body MR tomograph at the Institute for Clinical and Experimental Medicine in Prague. The objective of the thesis was to study differences in the biochemical processes and energy metabolism in the muscle tissue under physical workload between the groups of healthy subjects and patients with type 1 diabetes mellitus (DM1). We used phosphorous spectroscopy in combination with ergometer. The thesis is divided into five chapters. The first chapter describes theoretical introduction to in vivo 1 H and 31 P MR spectroscopy and muscle metabolism, the second chapter deals with the description of the experimental equipment and measurement, results of the thesis are reported in the third chapter and the fourth chapter is a discussion of results. Main result of this work is summarized in conclusion; we found differences between the metabolism of patients with DM1 and healthy volunteers.
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Cognitive functions training in elderly
Štěpánková, Hana ; Šípek, Jiří (advisor) ; Loneková, Katarína (referee)
This thesis is about cognitive training in older age. It connects the questions of aging and cognitive functions. Theoretical part deals with present state of knowledge, with focus on healthy population mainly, i.e. without cognitive impairment. The practical part is a research of memory training program effectiveness in cognitively intact elderly. Memory training is a popular name for interventions aimed at training of cognitive functions and activation of seniors; the last part is a brief methodological manual for memory trainers.
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Spin-lattice and spin-spin NMR relaxation of 1H nuclei in deuterated etanol and butanol doped by TEMPO radical
Matoušek, Jan ; Englich, Jiří (advisor) ; Štěpánková, Helena (referee)
The thesis deals with study of deuterated ethanol and butanol (ethyl-D5 alcohol, butyl-D9 alcohol) with a small amount (0 to 1.5% weight) of dissolved stable free radical TEMPO by methods of NMR. This system is used in polarized targets for high energy experiments. The linear dependence of spin-lattice and spin-spin relaxation rate of hydrogen nuclei from OH group of an alcohol on the radical concentration and dependence of the relaxation rates decreasing with temperature (in range from 250 to 298K) were obtained. The T1/T2 ratio from 1.3 to 2.0 was calculated. This was interpreted as an effect of a contact interaction via hydrogen bond between alcohol and radical molecules. The linear dependence of the resonance frequency of hydrogen nuclei from OH group on the radical concentration was obtained. The slope of the dependence line didn't change with temperature. Using this dependence the hyperfine constant of the interaction between hydrogen nucleus and the free electron of the radical was estimated approximately 8·10-28 J. It was found out that the lifetime of the hydrogen bonds between alcohol and radical molecules are about 10-11 s or longer.
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Theory of cleavages and development of Party System. Comparison of Czech Republic, Slovakia and Poland
Štěpánková, Helena ; Novák, Miroslav (advisor) ; Mlejnek, Josef (referee)
This diploma thesis deals with a development of the socioeconomic cleavage in the party systems of the Czech Republic, Slovakia and Poland in 2006 - 2012. At the beginning the theory of cleavages by S. Rokkan and S. M. Lipset and the enlargement to post-communist countries of Klaus von Beyme, are presented. There are also mentioned concepts of other authors. The thesis tries to answer a few questions. Firstly, what form did this line have in the monitored period (transformation line vs. classical socioeconomic line). Secondly, how big was an impact on the political right-left orientation of the political parties, and thirdly, how significant was this line for the party-political system of selected countries in this period. There is also a brief development of the party system after 1989 as well as the ideological profiles of parliamentary parties given in each chapter focused on particular country. One part of it deals also with the economic and social climate in the monitored period. Then the work is based mainly on the analysis of party's agenda, with an emphasis on the socioeconomic line.
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