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Host-parazite coevolution in aquatic environments
Hubová, Jana ; Petrusek, Adam (advisor) ; Votýpka, Jan (referee)
Antagonistic coevolution is a major driving force in the evolution of host and parasite. Parasites create on their host a time delay, negative frequency-dependent selection, which leads to oscillations in both genotypes of antagonists, as suggested by the Red Queen hypothesis derived for coevolution of host and parasite. The most commonly used systems for the study of host-parasite coevolution in an aquatic environment are (thanks to their features): diatom Asterionella and chytrid Zygorhizidium, aquatic snail Potamopyrgus and trematods Microphallus, water fleas Daphnia and their microparasites. Coevolution between host and parasite causes a number of phenomena, such as maintenance of genetic polymorphism, temporal oscillations of genotype frequencies, the persistence of sexual reproduction, parasite local and host adaptations. This thesis summarizes the current knowledge on the coevolution of the above-mentioned three host-parasite systems in the aquatic environment. Key words: Red Queen hypothesis, host-parasite coevolution, negative frequency-dependent selection, aquatic environments, Asterionella formosa, Potamopyrgus antipodarum, Daphnia.
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Practical teaching of scuba diving
Ďurík, Milan ; Fiala, Miloš (advisor) ; Bažant, Filip (referee)
Title: Practical teaching of scuba diving. Objectives: On the basis of the findings from the literature, information resources and consultation, establish a list of key skills taught in the practical teaching of the first scuba diving qualification level. Then select skills practiced in protected water environment and make the exercise sheets for them. Exercise sheets will include the skills, which correct acquisition should lead to passing the final examinations of this qualification. Methods: In this bachelor thesis was data obtained by examining expert documents and observation and interview methods. Basic information were obtained from documents dealing with the practical teaching of scuba diving. These information were then expanded by observation of teaching and interviews with experts on scuba diving training. Results: List of skills for practical part of the first scuba diving qualification leveland exercise sheets for these skills used for the needs of instructors and trainees. Key words: scuba diving, practical teaching, skills, exercise sheets.
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Study of 137Cs, 90Sr and 3H behaviour in hydrosphere in vicinity of Nuclear Power Plant Temelin
Ivanovová, Diana
The thesis focuses on an analysis of the results of long-term monitoring of the concentrations of 137 Cs, 90 Sr and 3 H in hydrosphere in the vicinity of Temelín Nuclear Power Plant. The monitoring was carried out during the period 1990-2008 subsequently in several projects, which include Research of impacts of Temelín Nuclear Power Plant on hydrosphere and other components of the environment (National project no. N 03-331-867), Research on impacts of nuclear facilities on the environment (VaV/510/1/96), Strategy and methodology of integrated studies of long-term trends in landscape development in close and wide vicinity of Temelín Nuclear Power Plant (VaV/640/8/03), Programme on monitoring and assessment of impacts of Temelín Nuclear Power Plant on the environment, and Monitoring for Czech Power Works, a.s., Nuclear Power Plant. The thesis was carried out in T. G. Masaryk Water Research Institute, public research institution. The radionuclides were monitored in surface water, river sediments, aquatic flora and fish species. The main objective of the thesis was to analyse and integrate all of the knowledge on concentrations and behaviour of these radionuclides, which originate mainly from residual contamination, in order to assess the impacts of Temelín Nuclear Power Plant (Temelín plant) on...
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Inter- and intraspecific variability in Vicia faba L. and Zea mays L. response to water deficit
Fridrichová, Lenka ; Holá, Dana (advisor) ; Zelenková, Sylva (referee)
This work monitors the response of plants to water deficit and subsequent restoration of water availability with the aim to expand our knowledge about plant behaviour during and after drought stress from the perspective of two plant species with a different type of photosynthesis. A particular attention was paid to the intraspecific differences and their possible changes during stress and post-stress periods. The plant response was monitored as the changes of selected photosynthetic, morphological and developmental characteristics caused by the cessation of watering for six days followed by a six-day period of renewed optimal water supply. The experiments were carried out on plants with different types of photosynthesis - C3 plant Vicia faba L and C4 plant Zea mays L.; for both plant species, three varieties / genotypes were monitored. The response of both plant species to insufficient water supply differed by the extent of changes in relative water content (RWC), chlorophyll fluorescence parameters, the dry mass of individual leaves (developed during the stress period), the ratio between the aboveground dry mass and dry mass of roots. In drought-stressed plants, downward trend in RWC was observed, as well as the increase of the minimum yield of chlorophyll fluorescence in dark-adapted leaves (F ),...
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Monitoring of oxidative stability of products from shell fruits
Krňávková, Martina ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The diploma thesis deals with the monitoring of oxidative stability of products, oils and butter, from nut fruits. The theoretical part concentrates on the topic of nut fruits, their properties, compositions which are closely related to the effects on the human health and the possibilities of technological processing. The lipid storage process, especially the most frequently occurring autooxidation reactions are described, followed by experimental part of the thesis. The changes in coconut, walnut, peanut oils and peanut butter samples are monitored during storage at 4 ° C and 20 ° C by determining the acid value, the peroxide value and the fatty acid composition by the GC-FID method. The lowest oxidation stability showed walnut oil due to the highest content of unstable polyunsaturated fatty acids – up to 88,7 %. During storage at 20 ° C there was a statistically significant increase in the content of primary oxidation products, determined as peroxide value PV = 2,55 ± 0,12 µgROOHg-1. An increase was also observed in samples of peanut butter, but it was mainly due to higher water activity, which is important for chemical reactions. The durability of this product after opening mentioned on the product label correlates with their low stability
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Složení a struktura plazmově stříkaných prášků chromové ocele
Schneeweiss, O. ; Voleník, Karel ; Kolman, Blahoslav Jan
Chromium steel powder (13% Cr) was sprayed by a water stabilized plasma gun. The changes of composition and structure occurring during two plasma spraying stages were studied. To characterize the main features of the first (in-flight) stage product, the molten powder particles flying in the plasma stream were trapped and quenched in liquid nitrogen. At the second stage, the particles were allowed to hit a solid substrate and to form a coating. The composition of the feedstock powder and the samples resulting from both plasma spraying stages were determined by chemical methods and X-ray microanalysis. Significant Cr-depletion was due mainly to selective oxidation of chromium at the in-flight stage. At the second stage, the composition changes were less important. Some details of the structure, in particular the distribution of Cr-atoms in the nearest neighbourhood of a Fe-atom, were assessed employing the results of Mössbauer spectroscopy.
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The Influence of eco-toxicological factors on spermatogenesis, morphology and function of mammalian sperm
Vašinová, Jitka ; Pěknicová, Jana (referee) ; Hortová, Kateřina (advisor)
An increasing infertility due to pathological changes on sperm has become a serious issue. A rising concentration of fluorides in the environment could be a potentially negative factor affecting the male fertility. Eco-toxicological effect of fluorides can be enhanced in the present of aluminium ions by forming fluoro-metallic complexes, analogues of phosphate groups that interfere with the activity of G-proteins and P-type ATPases, which are part of several signalling pathways during sperm maturation. The aim of this thesis was monitoring the effect of fluorides on mouse sperm capacitation in vitro, analysis of the effect of fluorides on male reproductive organ and on the level of mouse spermatogenesis. Fluorides were administered to mice through table water at the concentrations of 0, 1, 10, 100 ppm and at the same time we monitored their synergic action with aluminium at 10 ppm dose. The level of tyrosine phosphorylation in the sperm head was the main marker for successful capacitation in vitro. The results show that an oversized load of ions, to which mice were exposed, affected negatively spermatogenesis and ability of sperm to capacitate in vitro. Besides that, a multigenerational study in mice demonstrated that even low concentrations of aluminium fluorides can have a negative effect on...
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Unsegmented speech retrieval
Češka, Pavel ; Peterek, Nino (referee) ; Pecina, Pavel (advisor)
In this work I search through interviews of Czech witnesses of the holocaust from the MALACH project to find relevant parts of these testimonies. Audio records of these interviews are automatically recognized by a system for an automatic speech recognition. Automatically recognized texts are then lemmatized and tagged. In this work I present a script which generates parametrizable collections of documents from these preprocessed texts. The task of unsegmented speech retrieval is then reformulated to a task of information retrieval in this collections of documents. In this work, I describe many experiments which examine the influence of different retrieval techniques on retrieval results on this data collection. Mainly, I study an influence of a morphological normalization (lemmatization), different types of IR systems (TF-IDF model, Okapi model and Indri model), blind relevance feedback, stopword list based on frequencies of terms and part-of-speech categories. I also place emphasis on various values of length and overlap parameters of generated documents. The results of these experiments are verified on test data. Audio records, outputs from automatic speech recognition system and topics for information retrieval are not part of this work due to legal grounds.
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Preparatory training of swimming with mentally handicapped children
Krausová, Dana ; Čechovská, Irena (advisor) ; Peslová, Eva (referee)
Subject matter: Preparatory training of swimming with mentally handicapped children Objectives: The main goal of this research work is to outline and to check suitable didactic methods during preparatory swimming training lessons with mentally handicapped children. The analysis of specialized literature and the realization of experimental education make definding of informations and analysing of practical experience through the recommending-form for practical use possible. Method: The research work will observe abilities and swimming skills of mentally handicapped children during preparatory swimming classes. Method of qualitative, direct and participating observation will be used. Data will be collected in form of social survey with parents, casuistry and interviews with experimentee. At the same time further data will be gained with help of questionnaires for pedagogical workers. We will also use a method of evaluation, practical testing and scaling. Results: The research worked has proved that it always depends on the character, extent of handicap and on momentary mental condition of the individual. Preparatory swimming training with mentally handicapped children is time consuming and can take several years. The most important steps during preparatory swimming classes are adaptation to water, learning...
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Assessment of ecomorphological state and land use of Bylanka and Chotýšský brook flood plains
Slavíková, Pavlína ; Matoušková, Milada (referee) ; Lipský, Zdeněk (advisor)
This diploma thesis is dealing with geoecological assessment of water courses in the Bylanka catchment. The model area is situated in the Central Bohemia in the district Kolín. The catchment has a character of flat hilly country with the highest altitudes over 400 m. Most of the area is used as fields, forests cover only 9 % of the territory. Bylanka (8,4 km) and its longest affluent Chotýšský brook (10,6 km) were chosen as model water courses. The geoecological assessment is composed of three different methods. Ecomorfological assessment (Matoušková, 2003) was used for water courses evaluation. This method divides the stream and its surroundings into 4 ecomorfological zones: stream channel, vegetation belt, flood plain and water basin. The final ecomorfological state is better in the case of Bylanka because this stream is less anthropogenic transformed due to deeper erosive incision in the Permian-Carboniferous formations where human couldn't change the stream flow. Proliferation of bank and riparian vegetation is the second method of water courses and its surroundings evaluation. White willow (Salix alba), black poplar (Populus nigra), aspen tree (Populus tremula) and common alder (Alnus glutinosa) are the most frequently occurring wood species. Land use changes in the flood plain of Bylanka and...
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