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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Biosystematic revision of the Spergularia echinosperma complex

KÚR, Pavel January 2017 (has links)
This thesis is focused on the biosystematic study of the Central-European endemic Spergularia echinosperma. With the combined use of morphometric analyses, genome size measurements and molecular tools, the taxonomic issues associated with this species have been clarified. The existence of S. kurkae, a stable allotetraploid hybrid between diploid S. echinosperma and tetraploid S. rubra, has been proven. Based on several lines of evidence, including distinct morphological separation and frequent occurrence in the absence of the parental species, treating S. kurkae as a separate species is proposed. In addition, two infraspecific taxa within S. echinospermaS. echinosperma subsp. echinosperma and S. echinosperma subsp. albensisdiffering in distributions and ecology have been described. A complete revision of the localities of S. echinosperma, S. kurkae and S. rubra in the Czech Republic is also presented. Furthermore, the development of 16 polymorphic microsatellite loci for S. echinosperma is reported.
12

Systematika a proměnlivost zdravínku jarního Odontites vernus (Bellardi) Dumort. v České republice / Systematics and variation of Red Bartsia, Odontites vernus (Bellardi) Dumort. in the Czech Republic

BAĎUROVÁ, Tereza January 2012 (has links)
The Master's thesis studied the Odontites vernus group in the Czech Republic. The group was presented by two different taxa based on the seasonal types and the ploidy levels: an early flowering tetraploid Odontites vernus subsp. vernus (2n = 4x = 40) and a late-flowering diploid Odontites vernus subsp. serotinus (2n = 2x = 18). Plants from 33 populations were sampled for measuring the ploidy level and 27 morphological characters for morphological analysis. Two ploidy levels were confirmed in the Czech Republic and a new late flowering tetraploid taxon (2n = 4x = 40) was found. The three taxa were separated from each other based on the seasonal variation, ploidy level, morphology and ecology.
13

Průtoková injekční analýza prokainu a sulfamethoxazolu se spektrofotometrickou detekcí / The Flow Injection Analysis of Procaine and Sulfamethoxazole with Spectrophotometric Detection

Baptistová, Adéla January 2016 (has links)
A derivatization reaction, based on a copulation reaction of diazonium salt of an analyte with a reagent (1-aminonaphthalene or NEDA) producing colour, spectrophotometrically detectable product, has been used for determination of two analytes (procain hydrochloride, sulfamethoxazole) containing amino group in the molecule. The conditions of batch spectrophotometric determination were studied. It was found, that the batch determination is applicable only for procain hydrochloride analysis, because sulfamethoxazole gives time-unstable colour product. FIA arrangement was proposed and effects of selected parameters were optimized using two levels factorial design. The calibration dependences were measured for both analysis with both reagents, and subsequently were applied on determination of analytes in medical forms. Key words: diazotization, flow injection analysis, procaine, spectrophotometry, sulfamethoxazole
14

Vnitřní fluorescence bakterií Cupriavidus necator / Intrinsic fluorescence of bacteria Cupriavidus necator

Marková, Kateřina January 2018 (has links)
This thesis focuses on autofluorescence of flavins in gram-negative bacteria Cupriavidus necator H16 and its mutant strain PHB-4. The main methods used were fluorescence microscopy and flow cytometry. To confirm the presence of flavins, excitation and emission spectra of the bacterial suspension were measured, which were compared with flavin standards. In the part of testing cells without stress response, the autofluorescence of bacteria in PBS buffer and cell suspensions stained with fluorescence probe BODIPY 493/503 was measured. The ratio of short fluorescence lifetime to long autofluorescence lifetime, and its dependence on fluorescence probe was compared with previous conditions. Autofluorescence of the supernatant was measured; it was found that the relative amplitude of long lifetime was multiple times higher than in the cell. In the part devoted to the stress response, this thesis was focused on the amount of dissolved oxygen in the production medium and the effect on bacterial autofluorescence. Then differently concentrated hydrogen peroxide was used, the best results were obtained from the concentration of 100 mM in media. For comparison a combination of hydrogen peroxide with ferro-ammonium sulphate was used, but there was no big difference. Sodium azide and antimycin A were selected as substances that directly influence on bacterial respiratory chain. Both compounds affected change in the ratio of the relative amplitudes, but the distribution of these lifetimes and the autofluorescence change over time was affected only by sodium azide.
15

Analýza bakteriálních buněk pomocí průtokové cytometrie a fluorescenční mikroskopie / Analysis of bacrerial cells employing flow cytometry and flurescence microscopy

Müllerová, Lucie January 2016 (has links)
This thesis focuses on fluorescent analysis of viability and PHA content in bacterial cultures, the main methods of investigation were flow cytometry and fluorescent microscopy. In order to determine viability of C. necator H16, several viability probes were tested, nevertheless, only BacLightTM kit and propidium iodide can be used to estimate portion of viable and live bacterial cell in samples. Further, Acridine orange was used to monitor physiological state of bacterial culture and two hydrophobic probes, Nile Red and BODIPY 493/503, were used to investigate PHA content in bacterial cells. Application of BODIPY 493/503 seems to be promising since this probe does not require permeabilization of bacteria cells and it can be used along with propidium iodide. Furthermore, several fluorophores were tested in the microscopic part. In was found that concentrations used in cytometric analyses were too high for microscopic use. Emission from the SYTO9 fluorophore is seen mainly in the green channel but because of the high concentration some emission was visible in the red channel. Cells stained with BODIPY 493/503 had very high fluorescence intensities when the stain concentration was 10 . At the same time, negative amplitudes of fluorescence were measured in both strains of C. necator, but in case of C. necator H16 that amplitude was much more pronounced. In this strain surprising high concentration of BODIPY stain was observed on the surface of PHB granules. Anisotropy of the fluorophore was nearing 0 which is very surprising.
16

Zdroje variability v Sorbus aria agg. / Sources of Sorbus aria agg. variation

Bílá, Jana January 2015 (has links)
The main drivers of microevolution in the genus Sorbus are interspecific hybridisation and polyploidy. The fate of new hybrid and polyploid taxa is determined by their mode of reproduction. Especially apomixis could be very advantageous for these new taxa. The S. aria agg. (subg. Aria) plays an important role within the genus since its members are involved in all hybridisation events and thereby is responsible for the substantial part of variation of the genus. Flow cytometry, molecular markers and multivariate morphological analyses were employed to evaluate the processes generating the variability in the S. aria group. Three ploidy levels were detected among species from subg. Aria in the Czech Republic. All of them could be found in the South Moravia, whereas only tetraploids occur in the Bohemia region. Moreover, most of the Czech taxa (5 out of 7) grow also only in the South Moravia which is therefore considered as a centre of diversity of the genus Sorbus in the Czech Republic. Flow cytometry seed screen revealed 7 modes of reproduction among the individuals from S. aria agg. A wide range of sexual and apomictic types of reproduction including reduced and unreduced gametes was detected. All of the diploid individuals are completely sexual. Among polyploid taxa, most of the species are...
17

Imunofenotyp maligních buněk dětských akutních leukemií a jeho vývoj v průběhu onemocnění / Leukaemia associated immunophenotype in childhood acute leukaemias and its development during the course of disease

Podolská, Tereza January 2020 (has links)
Acute lymphoblastic leukaemia (ALL) is the most frequent childhood malignancy. One of the recent improvements in ALL treatment was the introduction of minimal residual disease (MRD) monitoring that enables risk stratification based treatment adaptation. The same MRD monitoring helps to choose relapse treatment, to guide indication for stem cell transplantation (SCT) and allows for a more personalized management of patients undergoing SCT. One of the main routes of MRD levels detection is characterisation of leukemic blasts using flow cytometry. However, flow cytometry is limited by its mainly manual expertise-based analysis. Such analysis is subjective and clearly insufficient for current complex data. While new computational tools are available for multidimensional flow cytometry data, there is an urgent need to test and adapt them for the use in clinical environment. The goal of this thesis is to detect immunophenotypes associated with leukaemia and their development by leveraging machine-assisted analysis of a set of diagnostic files selected based on information about more than three hundred thousand of multiparameter flow cytometry datasets. Advanced bioinformatic tools will help to detect blast and healthy haematopoietic populations, to derive their immunophenotypes and to identify individual...
18

Vodohospodářské řešení zásobního objemu nádrže Vranov / Water Management Analysis of Storage Capacity of the Vranov Reservoir

Vítková, Lucie January 2020 (has links)
The current persistent drought and changes in the climate system have raised water managers expert questions about how to manage water resources in the future. The manifestation of climate change in hydrological series and their influence on the magnitude of threats to the storage functions of reservoirs are more often investigated. Already today, long-term shortages of storage capacity in reservoirs lead to the introduction of special manipulations on water structures. The aim of the thesis is to perform the analysis of time series, respectively decomposition of hydrological series average annual and monthly discharges. Create extended hydrological bases using synthetic discharge series generators and develop a comprehensive analysis of storage volume without considering losses even with the introduction of losses from the water surface vapor in the UNCE RESERVOIR program. The created discharge series are compared and evaluated on the basis of statistical characteristics and reservoir storages results with the real discharge series. The practical app is conducted on the Vranov reservoir in the Dyje River Basin.
19

Imunofenotypové rozdíly v B lymfocytárních populacích non-memory B lymfocytů u zdravých kontrol a pacientů s imunopatologiemi. / Immunophenotype differences in non-memory B lymphocyte populations in healthy controls and patients with immunopathologies

Polák, Milan January 2014 (has links)
B-lymphocytes are a subset of immune cells that can be distinguished mainly by carrying clonally diversified membrane-bound immunoglobulin specialized to specific antigen recognition. Together with other immunocytes B-lymphocytes play a central role in adaptive immune system which takes part in defense of the host against wide variety of pathogens. Recently the evidence has supported the emerging concept of different B-cell subpopulations to play a direct or indirect role in a pathogenesis of spectrum of disorders. However, so far the knowledge has been limited mainly in the way of how the specific differentiation stages of B-lymphocytes are involved in pathogenesis of diseases and how course of disease, stage, and eventually different treatment can affect B-cell homeostasis. That is the reason for the thesis to be focused on an analysis of B-cell population profile changes in disease, identification of any association present among specific B-cell subpopulations, as well as association between these subpopulations and clinical parameters. Using polychromatic flow cytometry we analyzed frequencies of 11 B-cell subpopulations including stages of transient B-lymphocytes through effector antibody-producing plasma cells. We examined 81 individuals including 22 healthy controls and 59 patients with...
20

Genetická variabilita a evoluční vztahy českých endemických zástupců rodu Dianthus / Genetic diversity and evolutionary history of Czech endemic taxa from the genus Dianthus

Kalůsková, Jana January 2012 (has links)
Abstract This MSc. thesis deals with karyological, genetic and phenotypic variation of selected taxa from the genus Dianthus L. in the Czech Republic and adjacent countries. The evolutionary history of the genus has been shaped by several microevolutionary processes, including interspecific hybridization, genome duplication, and edaphic speciation. These processes led to the origin of a number of phenotypically similar taxa, which are often restricted to a narrow geographic area. One subendemic and three endemic taxa occur in the Czech Republic. These (sub)species were used as model groups to gain insight into microevolutionary processes in small populations and the postglacial development of the genus in Central Europe. The thesis consists of three parts, each addressing different evolutionary phenomenon: Dianthus arenarius subsp. bohemicus is a critically endangered endemic psammophyte currently known from a single population in Central Bohemia. The site is also inhabited by widespread D. carthusianorum. Interspecific hybridization has been suspected on the basis of morphological characters, but this has never been confirmed by any other technique. I exploited differences in the number of chromosomes between both species and, with the aid of DAPI flow cytometry, estimated relative DNA contents of...

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