National Repository of Grey Literature 7,556 records found  beginprevious7547 - 7556  jump to record: Search took 0.42 seconds. 

Modern multiple sclerosis treatment
Brázová, Květa ; Herink, Josef (advisor) ; Jílek, Petr (referee)
Diplomka thesis as concerned with the various symptoms of multiple sclerosis (RS). An investigative techniques used to diagnose MS are also described. These ones include basic clinical examination, examination of the eye background, lumbar puncture, magnetic resonance imaging and examination of the evoked potentials. There are following types of MS : Relapsing remitting, relapsing - progressive, primary- progressive, and secondary- chronic- progressive. The largest part of thesis discusses the current treatment of RS The treatment of acute attacks and of all types of this disease is described. The special interest to the mechanism of action and side- effects of these drugs is given. Finally the treatment of particular symptoms of MS is described An essential part of treatment of this disease belongs to the rehabilitation for improving and reconstruction of impaired movement and its function.

Impedance Measurement of Lead-acid Accumulator
Abraham, Pavel ; Dostál, Zdeněk (referee) ; Jareš, Petr (referee) ; Bača, Petr (advisor)
This dissertation deals with impedance measurements of lead-acid accumulator. Main aim was to study recent problems of impedance measurements of lead-acid accumulator and most importantly to extend difference method and also to interpret its results. The original DC difference method was developed earlier at our Power Sources Laboratory of Department of Electrical and Electronic Technology. The DC difference method and also the new AC difference method are both non-destructive, which means that experimental data can be obtained in situ. New method provides more accurate set of information because of its wide frequency range nature. Electrodes of lead-acid accumulator were analysed with special attention to collector / active mass double layer and to active mass itself. Various states and operation regimes were investigated. Obtained data contributed to better understanding of involved degradation mechanisms. Main aim of other experiment was to observe and interpret corrosion rates of electrode collector composed of various lead alloys. Last but not least charge and discharge regimes e.g. 100% deep of discharge regime, partial state of charge (PSoC) regime and pulse charge regime were analysed. BioLogic VSP was the device used for almost all experimental measurements. It takes a lot of effort to optimise VSP operation regime. Best operation regime of VSP for the difference method was suggested too.

Study of Alfven Eigenmodes in Tokamak COMPASS
Markovič, Tomáš ; Stöckel, Jan ; Seidl, Jakub ; Melnikov, A. ; Medvedev, S.
Having both MHD and kinetic character plasma Alfven eigenmodes are signicant not only on the eld basic plasma research, but also on the eld of magnetic connement fusion. An introduction to basic physical principles of Alfven eigenmodes under MHD approximation is provided. Presented results of recent experiments on COMPASS suggest occurrence of toroidal Alfven eigenmodes in this tokamak, which is further supported by preliminary linear MHD code simulations, althought more studies will have to be conducted in the future to further investigate presented modes therein.

Methods for Elemental Speciation of Arsenic Compounds.
Navrátilová, Jana ; Jarošová, Alžběta (referee) ; Golian,, Jozef (referee) ; Šimko, Peter (advisor)
Speciační analýza arsenu v různých matricích s využitím HPLC/ICPMS byla předmětem této práce. Toxicita arsenu závisí na oxidačním stavu a formě, ve které je přítomen. Znalost zastoupení specií arsenu je nutná k hodnocení toxicity a biodostupnosti. Obecně, anorganické specie jsou více toxické než organické. V práci byla studována degradace arsenocukrů v mořských řasách za simulovaných přirodních podmínek. Původní arsenocukry byly transformovány na arseničnan a kyselinu dimethylarseničnou. Arsen vstupuje do rostlin z půdy a vody a následně může vstoupit do potravního řetězce. S ohledem na tuto skutečnost byla speciační analýza provedena u vybraných vzorcích rýže, zakoupených v české obchodní síti. Stanovený celkový obsah arsenu se pohyboval v rozmezí 36.06 µg/kg - 218.11 µg/kg a hlavními speciemi byla kyselina dimethylarseničná a anorganický arsen (54-78%). Mořské ryby a tuky obsahují významnou část arsenu ve formě zvané arsenolipidy. Část práce byla zaměřena na analýzu arsenolipidů u máslové ryby (Lepidocybium flavobrunnrum) s celkovým obsahem arsenu 1.8 mg/kg a 22% celkového arsenu bylo vyextrahováno pomocí hexanu, což potvrzuje lipofilni charakter těchto sloučenin. Hlavní specií stanovenou ve vodném extraktu byl arsenobetain, představující 89%.

Accumulation and biotransformation of nitramines in plant tissue
Šídlová, Petra ; Skálová, Lenka (advisor) ; Szotáková, Barbora (referee)
Explosives are toxic, recalcitrant to degradation and contaminate large areas of land and ground water. Remediation of these xenobiotics is difficult and an enormous logistical task. Phytoremediation is a technique that offers an environment friendly, low-cost alternative to current remediation techniques. However this approach is hindered by the low metabolic abilities of plants towards these xenobiotic compounds and the phytotoxicity of these compounds. The fate of the explosives RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) on exposure to plant was investigated in hydroponic system of sunflower (Heliantus annuus L.) and hemp (Cannabis sativa L.) approximately for more than 10 days. Exposure levels were: 10mg/l and 50mg/l RDX, respectively HMX for sunflower; 25mg/l and 50mg/l RDX , 5mg/l and 50mg/l HMX for hemp. Their ecotoxicites were characterized by the test based on the inhibition of elongation of primary roots 3days-old mustard and hemp seedlings. Extracts of plants were analyzed by HPLC (liquid chromatography). These study showed that RDX and HMX was taken up by both plant species. The accumulation of these nitramines was observed more in the roots than in the aerial parts of the plants, except for RDX in hemp, where the...

Pěvecký formant: Předběžné výsledky vyhodnocení snímků z magnetické rezonance a akustických záznamů při fonaci zpěváků
Švec, J. ; Herbst, C. ; Havlík, R. ; Horáček, Jaromír ; Krupa, P. ; Lejska, M. ; Miller, D.G.
Singerś formant is a desirable quality in operatic singing. This study investigates the strategies of two male operatic singers used for achieving the singerś formant. The subjects were asked to produce voice both in naïve and operatic singing quality at the same fundamental frequency for two different vowels [a] and [e]. Changes in the shape of the vocal tract were investigated using magnetic resonance imaging (MRI), and differences in acoustic voice quality were analyzed using sound spectrography. In operatic voice quality the MR images revealed a) lowered larynx, b) raised soft palate, c) flattened tongue and d)straightened spine. Clustering and lowering the formant frequencies was seen in the spectrograms but the strategy was different for the two vowels and the two singers. The data suggest that different anatomical dispositions in singers lead to different strategies for optimizing the voice quality.

Importance of imaging methods in neurology
Drábová, Zuzana ; Lisý, Jiří (referee) ; Kynčl, Martin (advisor)
The nervous sytem is one of the most important organ system of the human body. All the functions of the body are regulated and controlled by the nervous system, which consist of two main divisions: 1. the cerebrospinal nervous system - systema nervosum centrale 2. the peripheral nervous system - systema nervosus periphericum. Neurology is very large branch and that's also the reason why there are use many of the imaging methods which help the neurologists first in the diagnostic. In dissertation I deal with the importance such methods like are e.g. magnetic resosnance imaging (MRI) , computer tomography (CT), digital substraction angiograpgy (DSA) and the other. There will be described a progress of investigation and especially the importance and applying the technology to the neurology. Analysis the role of the radiologic technician in neurology is the separate chapter, where I try to sum up the way of applying the radiologic technician in so-called auxiliary neurological investigations. Powered by TCPDF (www.tcpdf.org)

Magnetism in transition metal oxides
Burianová, Simona ; Kalbáčová Vejpravová, Jana (advisor) ; Svoboda, Pavel (referee)
The CoFe2O4 nanocrystals are highly attractive due to their magnetic properties - large coercivity (up to 2 T at low temperatures) with moderate saturation magnetization (80 A.m2.kg-1), remarkable chemical stability and mechanical hardness. Upon RE doping, a significant change of the properties is expected. This thesis is focused on investigation of Co1-LaxFe2O4, x = 0.05 - 0.5 and CoLaxFe2-x O4 x = 0.05 - 0.2 nanoparticles prepared by sol-gel and microemulsion method, respectively, with varying particle size according to the final heat treatment. In the former case, the particles were embedded in amorphous SiO2 matrix, while in the latter case, the samples were matrix-free. The samples were characterized using X-ray diffraction and Mössbauer spectroscopy. Measurements of the temperature dependence of the ZFC-FC magnetization revealed that the blocking temperature is above the room temperature. The values of coercivity and saturation magnetization strongly depend on particles size determined by method of preparation. The higher coercivity values of about 2 T at 10 K show the samples prepared by the sol-gel method. The obtained results are discussed in the context of preparation method, particle size and level of La doping.

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.

Enzyme hydrolyses of wheat gluten for the gluten free application
Svobodová, Dominika ; Vránová, Dana (referee) ; Ing.Silvia Mošovská,Ph.D. (advisor)
Celiac disease is attributable to autoimmune diseases, where treatment is based on absolute respect for gluten-free diet. As the gluten used widely in all areas of food production, strict adherence to a gluten-free diet really can be difficult for people with celiac disease. Products suitable also for those suffering from the disease are usually expensive. Finally, patients that undergo exclusively on a gluten-free diet are robbing the important nutritional components. Therefore, interest in this type of products innovation enhance as to the nutritional, technological, as well as organoleptic properties. The aim of this final thesis was to draw up literature review of the celiac disease and gluten allergen, or his particular part of gliadin. In the experimental part, attention was focused on the first hydrolytic cleavage of starch, the substrate was sterilized wheat flour and water, where is incorporated spiral just gluten. The best ability of degrading the starch grains, the combination of enzymes and MT3K and GLUAMK concentration of 0, 1% over 4 hours of action, as indicated by a reduction in the starch content of the original amount of 72,65 % at a concentration of 29,00 %. The next item of work distribution used different proteases, to reduce the amount of gliadin to below 20 ppm per kilogram of final product. Low levels investigated allergen (10,79 ppm/kg) recorded by the enzyme combination exoprotease Flavourzyme (0,1 %) and endoprotease Neutral Protease (0,1 %) at 7 hours hydrolytic action. The conclusion of the thesis was prepared several alternatives gluten-free breads and through sensory evaluation assessed the characteristics of color, aroma and taste to predict the location of the products on the commercial market.