Microscopy of Time Variable Biologic Objects

Předmětem disertační práce je využití transmisního digitálního holografického mikroskopu (DHM) navrženého a zkonstruovaného v Laboratoři optické mikroskopie na ÚFI VUT v Brně pro výzkum dynamiky živých buněk. První část práce se zabývá teoretickým popisem vlastností zobrazení mikroskopu v závislosti na koherenci osvětlení doplněným experimenty s modelovým a reálným biologickým vzorkem. V další části jsou popsány konstrukční změny a inovace mikroskopu a jeho vybavení, které umožnily využívání mikroskopu pro pozorování živých buněk. V~experimentální části byla vypracována metodika přípravy a pozorování živých buněk pro DHM, která byla ověřena při zobrazení dynamiky buněčné apoptózy indukované cytostatikem cis-platinou. Byla zkoumána také dynamika živých buněk při standardních podmínkách a za působení deprivačního stimulu. Pro vyhodnocení kvantitativních změn rozmístění buněčné hmoty během experimentů byla vytvořena metoda zpracování holograficky rekonstruované fáze nazvaná "dynamické fázové diference". Touto metodou byly odhaleny různé vzorce chování rakovinových buněk během specifické reakce v závislosti na typu buněk, stupni jejich malignity a hustotě porostu. Pro kvantitativní analýzu fázového zobrazení z DHM byla navržena vhodná statistická charakteristika a způsob interpretace naměřených dat, které byly úspěšně aplikovány při porovnání vnitrobuněčného pohybu dvou typů rakovinových buněk rodičovské a dceřiné linie. Na základě uvedeného zpracování pozorování byly stanoveny hypotézy o mechanismu reakce nádorových buněk na nepříznivé životní podmínky.The subject of the PhD thesis is the application of a transmission digital holographic microscope (DHM) which was designed and constructed in the Laboratory of optical microscopy at the IPE BUT for the research of live cells dynamics. First part of the work is concerned with theoretical description of the microscope imaging properties dependent on the coherence of illumination. It is supplemented with experiments of imaging of a model and a real biological specimen. The following part describes construction modifications and innovations of the microscope and its equipment that enabled the utilization of the microscope for live cells observations. In the experimental part the methodology of live cells preparation and DHM imaging was worked out. The methodology was verified by the observation of cell dynamics during an apoptosis induced by the cytostaticum cis-platinum. Further experiments examined the dynamics of live cells in standard conditions and during a deprivation stimulus. A novel method of holographically reconstructed phase, named \uva{dynamic phase differences}, was set up to evaluate quantitative changes of cell mass distribution during the experiments. Depending on the degree of malignancy and density of cell outgrowth, various schemes of cancer cells behaviour during a specific reaction were revealed using this method. For the quantitative analysis of the DHM phase imaging, a suitable statistical characteristic and an interpretation of the measured data were proposed. Both of them were successfully applied for the comparison of cell motility of two cell types: parental and progeny cell lines. On the basis of the proposed processing, hypotheses describing the reaction mechanism of tumour cells to stress life conditions were established. In the conclusions we summarize our findings and suggestions for the construction and the applications of a new generation of the transmission DHM.

Solution growth of Ce-Pd-In single crystals: characterization of the heavy-fermion superconductor Ce2PdIn8

Solution growth of single crystals of the recently reported new compound Ce2PdIn8 was investigated. When growing from a stoichiometry in a range 2:1:20 - 2:1:35, single crystals of CeIn3 covered by a thin (~50 um) single-crystalline layer of Ce2PdIn8 were mostly obtained. Using palladium richer compositions the thickness of the Ce2PdIn8 layers were increased, which allowed mechanical extraction of single-phase slabs of the desired compound suitable for a thorough study of magnetism and superconductivity. In some solution growth products also CePd3In6 (LaNi3In6 - type of structure) and traces of phases with the stoichiometry CePd2In7, Ce1.5Pd1.5In7 (determined only by EDX) have been identified. Magnetic measurements of the Ce2PdIn8 single crystals reveal paramagnetic behaviour of the Ce3+ ions with significant magnetocrystalline anisotropy. Above 70 K the magnetic susceptibility follows the Curie-Weiss law with considerably different values of the paramagnetic Curie temperature, for the magnetic field applied along the a- (-90 K) and c-(-50 K) axis. Below the reported critical temperature for superconductivity Tc (0.69 K) the electrical resistivity drops to zero. Comparative measurements of the electrical resistivity, heat capacity and AC susceptibility of several crystals reveal that the superconducting transition is strongly sample-dependent.Comment: submitted (2Nov09) to Intermetallic

White lupin bran and its effects on the growth performance, carcass characteristics and digestibility of nutrients in fattening rabbits

[EN] The purpose of the present study was to evaluate the effects of including white lupin bran (WLB) in a fattening rabbit diet on growth, carcass traits and nutrient digestibility. The C diet (control) based on alfalfa meal, whereas the WLB 5 and WLB 15 diets were based on white lupin bran (crude protein 152 g/kg, neutral detergent fibre 524 g/kg as-fed basis). The WLB 5 diet contained 50 g of white lupin bran/kg instead of 50 g of alfalfa meal/kg, whereas the WLB 15 diet contained 150 g of white lupin bran/kg, 5 g of soybean meal/kg and 10 g of sugar beet pulp/kg instead of 165 g of alfalfa meal/kg. The diets had similar digestible protein/digestible energy ratios. A total of 150 Hyplus rabbits between the ages of 30 to 73 d were randomly allocated into one of 3 groups and fed one of the 3 experimental diets. Additionally, another 30 Hyplus rabbits (10 per dietary treatment) at the age of 30 d were selected to determine coefficients of total tract apparent digestibility (CTTAD) of diets between 63 and 67 d of age. The dietary treatments did not affect the final live weight of rabbits (mean=2969 g). There was a higher feed intake (+30 g/d; P<0.001) in both groups of rabbits fed the WLB 5 and WLB 15 diets compared to rabbits fed the C diet, which led to impaired feed conversion ratios (P<0.001). Sanitary risk index was not affected by dietary treatment. The rabbits fed the WLB 15 diet exhibited a higher drip loss percentage (+0.65%; P<0.001) than the rabbits fed the other diets, as well as a lower dressing-out percentage (by 1.6%; P=0.024). The CTTAD of the lignocellulose fraction (acid detergent fibre) was significantly higher in rabbits fed the WLB 5 and WLB 15 diets than in those fed the C diet. White lupin bran may be used as a dietary fibrous by-product without significant impairment of the nutritive value of the diet. This lupin by-product can be included in diets for fattening rabbits up to 15% as a partial replacement of alfalfa meal.Uhlířová, L.; Volek, Z.; Marounek, M. (2018). White lupin bran and its effects on the growth performance, carcass characteristics and digestibility of nutrients in fattening rabbits. World Rabbit Science. 26(1):1-6. doi:10.4995/wrs.2018.8781SWORD1626

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