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Methods for distinguishing fossil and recent organic matter in post mining soils
Vindušková, Olga ; Frouz, Jan (advisor) ; Jehlička, Jan (referee)
Soil organic matter (SOM) has many important effects on soil and ecosystem quality. Soils developing on post-mining sites are characteristic of low recent SOM, but can contain reasonable amounts of fossil SOM originating from coal, kerogen or other fossil component of the overburden. With time, as vegetation develops, SOM accumulates and improves overall quality of post-mining soils. To assess soil quality development and quantify sequestered carbon, a reliable method for distinguishing recent and fossil SOM is needed. The relative amounts of recent and fossil carbon can be successfully quantified by the radiocarbon method, but due to it's high cost, it's common application is unlikely. The aim of this study was to (1) quantify the amount and variability of fossil SOM in post-mining soils near Sokolov, (2) compare different other SOM quantification methods to this reference, (3) test the potential of near infrared spectroscopy for recent and fossil carbon quantification. Fossil carbon accounts for 13 to 99 % of total organic carbon in studied soils, which is equivalent to 2 - 6% carbon content. Subtracting the carbon content of a deeper horizon (50 cm) from the content of A horizon provides a good estimate of recent carbon. This can be applied to carbon contents from dry combustion, wet dichromate...
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Raman spectrometry of pigments of cyanobacteria, algae and lichens in the astrobiology context
Kovács, Michal ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
This work deals with the possibility of Raman spectroscopical identification of selected biomarkers of extremophile species. It focuses mainly on selected cyanobacteria, algae and lichens with an emphasis on the ability to detect carotenoids. These pigments exhibit three characteristic bands of Raman spectra which represent stretching vibrations C=C; C-C and bending vibration C-CH3 in molecules of carotenoids. Raman spectra were measured not only by laboratory microspectrometers (λ - 514 nm and 532 nm), but also by portable and handheld spectrometers (λ - 532 nm, 785 nm and 700 - 1100 nm). In the case of cyanobacteria, the spectroscopical analysis was performed also on the fractions obtained by high performance liquid chromatography (HPLC). This work critically evaluates the possibilities of Raman spectroscopy to identify the carotenoids of cyanobacteria, algae and lichens. Besides the signal of carotenoids, interpretation of other bands in the Raman spectra corresponding to the presence of other biomarkers is given here for selected samples. The obtained Raman spectra of carotenoids should be interpreted with great caution, because of the ifluence of several factors, which potentially cause unsystematic shifts in the positions of Raman bands (carotenoids bond in biological tissue, interactions with...
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Oxalates in rocks and plants
Novotná, Julie ; Jehlička, Jan (advisor) ; Hruška, Jakub (referee)
SUMMARY: The presence of oxalates is widespread not only as kidney stones, but in whole nature. It is well known that oxalates are products of some plants, fungi and lichens. The accumulates of calcium oxalates are increased in: sorrel, rhubarb, spinach, soya, dieffenbachia, etc. Oxalates serve many important functions in plants such as calcium regulation, protection from herbivory and metal detoxification. Aluminum detoxification is ability of plants, which is critical factor for crop production. Breeding of commercially viable low oxalate cultivars or genetic manipulation with crops should deal to enhance of nutritional quality and enhance of agricultural production too. The presentation of oxalates in rocks is well representing by calcium oxalate minerals, whewellite and weddellite. Minerals occur in sediments into precipitated forms within concretions and hydrothermal veins or dispersed form into modern sediments, e.g. peats. Oxalates are biologic products, therefore they can indicate biological activities, so oxalates should be sought for researching on cosmic objects. The observation of oxalates on Earth and interpretation of the Raman spectra is necessary in these types of study.
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Use of handheld Raman spectrometers for identification of secondary minerals in situ
Kdýr, Šimon ; Jehlička, Jan (advisor) ; Culka, Adam (referee)
Summary: The sulfates are secondary minerals, that are occurring in the different terrestrial conditions. Their study is useful for understanding of the processes, that are leading to occurence the acid mine drainage. Next sphere of research is out of our globe (it means Mars). The Raman spectroscopy is nondestructive analytical method, that it is advantage of this method. It has occured great development on the field of miniaturisation in a few last years. It is opportunity for aplication out of laboratory and it is possible to make a study in field conditions. At the introduction, this work is occupied with instrumentations, advantages and disadvantages of the use mobile Raman spectrometers. You find there summarises publications, that are occupied with mineralogy, origin of sulfates and opportunities of application mobile Raman spectrometers for their study. At the end of the recherche, it shows some particular localities, where it could be applicable for study sulfates by Raman spectroscopy and where mobile Raman spectrometers were used for identification of sulfate minerals.
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Raman spectrometry of carotenoids of selected microorganisms
Novotná, Julie ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
In this thesis Raman spectroscopy is evaluated as a tool of identification and discrimination of carotenoids from microbial biomass. Microorganisms, halophilic or nonhalophilic, belong to Cyanobacteria, Proteobacteria, Chlorophyta, Rhodophyta and to others. Biomass was cultiveted under laboratory conditions and yielded varied colours. Raman spectra were recorded succesfully from lyophilized biomass by excitation wavelenth 514.5 nm (dispersive Raman microspectrometr) and 1064 nm (FT Raman spectrometer). Results were compared with Raman spectroscopic data from pigment extracts. Spectra of carotenoids are characterized by the main Raman bands υ1, υ2 a υ3 due to C=C stretching, C-C stretching and C-CH3 deformation. HPLC/UV-VIS allows effective pigment separation from extracts and detection of separated pigments by UV-VIS analyzator. Assessment of Raman analysis and its potential to detect microbial carotenoids are discused. Sarcinaxantin is an unusual carotenoid identified together with more common β - carotene. Raman spectroscopic results obtained on carotenoids recorded from colonies which accumulated more than one carotenoid need to be interpreted carefully. Powered by TCPDF (www.tcpdf.org)
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Spatial cognition of users of spoken Czech and Czech Sign Language: How cross-linguistic diversity affects non-linguistic thought
Jehlička, Jakub ; Chromý, Jan (advisor) ; Smolík, Filip (referee)
The thesis focuses on how different languages influence spatial cognition of their speakers, i. e., whether and how the differences in spatial language (linguistic representation of perspective, location, spatial scenes etc.) affect the non-linguistic spatial reasoning (orientation, spatial memory etc.). This issue has for a long time been a part of the studies of the relation between language and thouhgt under the flag of so called Sapir-Whorf hypothesis/Hypothesis of linguistic relativity. In the first half of the theoretical part of the thesis, I attempt to summarize the history of the concept of linguistic relativity since 1950s and to revise some critical claims about linguistic relativity by re-reading Whorf's works (chapter 2). The second half of the theoretical part (chapter 3) focuses in particular on the research of the interrelations between spatial thought and language. In section 3.1, I make a brief note on the notion of space in terms of cognitive linguistics. Section 3.2 provides an selective overview of the previous research of the crosslinguic spatial-cognitive diversity. Sections 3.3 and 3.4 connect the theoretical and the empirical part of the thesis. The research itself is presented in the chapter 4. It experimentally tests the hypothesis, that the language-specific...
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Current exobiology missions to Mars. Importance for geoscience and search of Life beyond Earth
Ovcharenko, Vladyslav ; Jehlička, Jan (advisor) ; Culka, Adam (referee)
The relevance of the topic of the bachelor's thesis "Current exobiology missions to Mars" is associated with the awareness of the similarity of some conditions and processes on Earth and Mars. Compared to other planets of the Solar system, Mars is somehow relatively close to our planet in major characteristics: the inclination of the equatorial plane, relief, the length of the day, some atmospheric processes, temperature conditions, etc. Having studied the processes taking place there now, we can better deal with the past and predict the future evolution not only of Mars, but also of Earth. The aim of this work is to overview the current exobiological missions of NASA and ESA to Mars and the assessment of the importance of the information received for earth sciences and search of life beyond the Earth. The subject of Exobiology consists in studies of potential origin, evolution, spread of life on other planets of the universe. Exobiology includes search for habitable environments both in the Solar system and beyond, detecting biomarkers, search of evidence of prebiotic chemistry, and research on potential possibilities of life in terms of adapting to extreme conditions in space. Based on the foregoing, we can state that the exploration of Mars opens up grandiose prospects for science and technology...
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Reflexive alternation in language processing by persons with aphasia
Suchý, Daniel ; Láznička, Michal (advisor) ; Jehlička, Jakub (referee)
The goal of this thesis is to design an experiment that researches how frequency of use and grammatical structure affect sentence comprehension in speakers with aphasia. An additional objective is to verify this design in an experiment on healthy speakers. Introduction to the topic of aphasia is pro- vided from a linguistic perspective, followed by a description of usage-based approach to aphasiology, which will be utilised in the practical part of this the- sis. The practical part of the thesis consists of a corpus-based research on the use of reflexive constructions in Czech, followed by an experiment that tests comprehension of such sentences in healthy speakers. Using corpus data, a set of experimental items that can be used to test the comprehension of reflexive sentences was created. The experiment verified that the healthy participants evaluate the grammaticality of these sentences as expected in the vast majority of cases. The results of the experiment show a weak effect of sentence struc- ture and no effect of frequency of use and verb lemma on comprehension. This indicates that healthy speakers find these sentences easy to process and that the design is valid. Based on these results, a design of an experiment that tests reflexive sentence comprehension in Czech speakers with aphasia is proposed. 1
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Gesture and eventuality: a cross-linguistic study
Jehlička, Jakub ; Fulka, Josef (advisor) ; Janda, Laura Alexis (referee) ; Hinnell, Jennifer (referee)
Mluvčí typologicky odlišných jazyků volí různé strategie při popisu stejné události v závislosti na dostupných jazykově-specifických gramatických prostředcích. Tyto strategie se projevují např. různými způsoby konceptualizace událostních rámců bě- hem jazykového vyjádření, ale v nejazykové kognici. Jedním z jevů, které byly v této souvislosti zaznemány, jsou jazykově specifické způsoby gestikulace doprovázející mluvené popisy událostí, které reflektují (či manifestují) tělesně ukotvená konceptuál- ní schémata, na nichž naše vnímání událostí stojí. Tématem této práce je multimodální konstruování (construal) událostí v češtině a v angličtině. Konkrétně se práce zaměřuje na spojitosti mezi formálními rysy gest (způsob pohybu a jeho zakončení) a sémantické rysy, které konstituují tzv. aspektuální kontury událostí (konstruování časového a kvalitativního průběhu události). První část prezentovaného výzkumu tvoří analýza materiálu z českého a anglického multimodální korpusu. Oba použité korpusy obsahují nahrávky spontánních pro- jevů v interakcích zachycených během pracovních jednání v akademickém prostředí. Kvantitativní analýzy (metoda tzv. klasifikačních stromů a náhodných lesů) ukázala, že a) v angličtině je významným prediktorem výskytu gest s rysem ukončenosti aktion- sartová kategorie achievement...
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