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Studium magnetismu hranic zrn z prvních principů
Čák, Miroslav ; Šob, Mojmír ; Hafner, J.
Grain boundaries (GBs) represent an important class of two-dimensional extended defects in materials. Segregation of impurity atoms is responsible for a degradation of mechanical properties. Recently, it was found that application of magnetic annealing leads to decreasing concentration of impurities at GBs in Fe-0.8%Sn alloy and improves its ductility To understand the mechanism of this process it is necessary to study magnetism of clean GBs as well as of GBs with segregants at the microscopic (ab initio) level. In the present work, we investigate the Sigma5(310) GB in iron.
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Study of preparation of ceramic membranes
Matějková, Michaela ; Částková, Klára (referee) ; Bartoníčková, Eva (advisor)
In this bachelor thesis the literature retrieval concerning the preparation of ceramic membranes suitable for power applications (membrane reactors, fuel cells) and materials suitable for their preparation, was summarised. Based on that literature retrieval the glycine-nitrate syntheses of selected ceramic materials were performed. As starting material was chosen zirconate structure (Zr-Ba-O), which was doped by cerium, iron, aluminium and manganese ions. The resulting powders were further processed to solid membranes by unaxial pressing and sintering (density of sintered bodies about 93 % t. d.). Then the influence of dopants on the properties of the powders and ceramic membranes were studied. The evaluation of properties (as phase composition, powders morphology and microstructure of ceramic bodies) was performed by x-ray analysis, scanning electron microscopy, a specific surface analysis and simultaneous thermal analysis.
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Nízkocyklová únava tvárné litiny s 2,8 % niklu
Tesařová, H. ; Petrenec, Martin ; Pacal, B. ; Musilová, I.
Cast ductile iron with the ferritic matrix alloying with 2.8% Ni was subjected to cycling with constant strain amplitudes and the cyclic stress-strain response and fatigue life were studied experimentally. The original microstructure is documented using light microscope. Fracture surface was studied using scanning electron microscopy. Manson-Coffin and Basquin laws can reasonably approximate the fatigue life data. Fatigue crack initiation from shrinkage cavity is documented.
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The study of genetic changes of children patients suffering from the acute lymphoblastic leukemia (ALL) using mFISH / mBAND and micro-arrays.
Bártů, Linda ; Zemanová, Zuzana (advisor) ; Březinová, Jana (referee)
Acute lymphoblastic leukemia is the most common malignancy in children. The most important examination at the time of diagnosis includes karyotype of leukemic cells which divides patients into prognostic groups according to cytogenetic finding. In up to 90 % of patients the chromosomal aberrations with well known clinical significance are designated. One of cytogenetic type is high hyperdiploid ALL (51-68 chromosomes) associated with favorable prognosis. Nevertheless, relapses of the disease occur even in these children. One possible reason why this happens could be an increased genomic instability of leukemic cells that causes cryptic structural rearrangements. In a retrospective study, we examined a total of 232 children with newly diagnosed B-ALL using conventional cytogenetic analyses and interphase fluorescence in situ hybridization (I-FISH) with a panel of DNA probes (Abbott Vysis) in order to detect heteroploid cells. In patients with suspect cryptic structural chromosome aberrations, we analyzed the karyotypes in detail by multicolor FISH and multicolor banding (mFISH/mBAND; MetaSystems). The extent of aberrations was determined by comparative genomic hybridization on BAC arrays (array CGH; BlueGnome). Cell clones with high hyperdiploid karyotype were detected in a total of 102 children (44 %). In...
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Study of biofilm Pseudomonas aeruginosa and introduction of new method for antibiotics susceptibility
Mošničková, Markéta ; Melter, Oto (advisor) ; Chrenková, Vanda (referee)
Biofilm is a complex structure produced by bacterial cells which contain highly hydratated filamentous exopolysacharides. Biofilm exists everywhere in our surroundings or nature. It creates for instance a sticky viscous structure covering the surface of stones or other solid objects underwater. The technology of sewage cleaning remediation is essentially dependent on the presence and function of biofilm producing bacteria. Adhered biofilm in medicine has usually negative consequences for patient health, hence, reduction of its role is a goal of researches in the field. Here biofilm first of all adheres and colonizes catheters or artificial joints or other implants and is a source of a chronic infection which limits the healing process or normal function of the implants. In cytic fibrosis patient biofilm production is also responsible for the fact that acute infection caused by P. aeruginosa could change within a few months in chronic infection when mucoid strain could be cultivated from the patient. In my bachelor thesis I have analyzed clinical material and bacterial isolate of P. aeruginosa of a cystic fibrosis patient which dissociated into mucoid and smooth phenotype using light-, electron- and immunofluorescence microscopy. I have applied an original method using resuspended bacterial culture in solid...
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Studium rovnováhy mezi klesajícími kapkami železa a roztavenými silikáty v magmatických oceánech
Ulvrová, Martina ; Velímský, Jakub (advisor) ; Šrámek, Ondřej (referee)
During the Earth's accretion process deep magma oceans were episodically formed. Differentiation of iron took place within the melted zone and small droplets of iron were sinking to the base of the magma ocean due to the density contrast. In the present work we study the process of equilibration between dispersed metal droplets and surrounding silicates that proceeds by the advection transport and diffusion at the rim. We allow for steady state ow of a spherical liquid blob falling in a host liquid and establish the numerical code in axisymmetric spherical coordinates computing the chemical evolution of such heterogeneous system. We focus on determining the time scales of equilibration for which we propose an analytical model based on the boundary layer analysis. The obtained characteristic times are especially for low silicate viscosities very short that supports the idea that the drops attained equilibrium while sinking.
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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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The role of nurses to reduce patients suffering
DAŇKOVÁ, Patricie
The bachelor thesis deals with participation of a nurse in relief of patient suffering.The present state of the issues of nursing care of a suffering patient is a part of the text. The research part of the thesis was based on qualitative research, where the techniques of nonstandardized interview and observation of patients and nurses in Kutna Hora Hospital were applied. The aim of the work was to find out how a nurse participates in suffering relief in patients, to examine the techniques a nurse applies to relief of suffering, to learn how a patient perceives a nurse in relieving his/her suffering. The research has shown the spheres where patients often suffer, where and how the approach of nurses may beimproved.The thesis wanted to find the weak points in providing nursing care to the suffering, to map whether nurses are active in their work, have humane approach and provide quality care.The thesis will be made available to the Hospital management, it may be a complementary source of information for those who study these issues and the research results may serve as educational material for nurses working not only at the aftercare wards but also at acute care beds as suffering occurs in patients of all the clinical fields. Nurses may only participate in suffering relief efficiently if they know it and pay due attention to it.
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STUDY OF POTENTIAL PHARMACOLOGICAL PROTECTION OF CARDIAC CELLS AGAINST OXIDATIVE STRESS AND ANTRACYCLINE ANTICANCER DRUGS
Jansová, Hana ; Šimůnek, Tomáš (advisor) ; Hrdina, Radomír (referee) ; Jun, Daniel (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF BIOCHEMICAL SCIENCES Candidate: Mgr. Hana Jansová Supervisor: Doc. PharmDr. Tomáš Šimůnek, Ph.D. Title of Doctoral Thesis: STUDY OF POTENTIAL PHARMACOLOGICAL PROTECTION OF CARDIAC CELLS AGAINST OXIDATIVE STRESS AND ANTRACYCLINE ANTICANCER DRUGS Development of cardiovascular disorders is associated with various risk factors and oxidative stress plays an important role in many of them. Iron-catalysed production of highly toxic and reactive hydroxyl radicals may contribute to oxidative stress. Chelation of free iron seems to be a promising strategy to prevent the propagation of oxidative stress. However, the use of classic iron chelators in pathological conditions without iron overload is associated with the risk of toxicity due to the iron depletion. Hence, this study deals with cardioprotective properties of iron chelators as well as prochelators derived from them. We focused on prochelators with almost no affinity for iron ions until they are activated under disease-specific oxidative stress conditions. For a long time, it has been assumed that oxidative stress is also the main denominator in an anthracycline-induced cardiotoxicity. However, the previous studies suggested alternative mechanism(s). Therefore in the...
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