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Toxicity of nanotextiles as respirators waste to Daphnia Magna
Slaný, Jan ; Roupcová, Petra ; Pavlovský, Jiří ; Klouda, Karel
In recent years, the prevalence of nanotubes has increased due to the covid-19 disease situation worldwide. Nanotextiles are used in the form of face masks and respirators, which are a source of environmental pollution by nanoparticles. The aim of this paper is to perform ecotoxicological tests according to European standards and Czech legislation. First, non-woven fabrics are briefly described and a small planktonic crustacean (Daphnia magna S.) is introduced. The second part focuses on the experiments themselves and their results. In all cases, the nanotextiles tested did not have a toxic effect on the organisms, but a reaction could be observed. Further tests will be carried out to explain and clarify the effects.
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Palaeoecology of selected localities of the Whetstone Horizon
Libertín, Milan ; Kvaček, Jiří (advisor) ; Teodoridis, Vasilis (referee) ; Cleal, Christopher J. (referee)
Palaeoecology of selected localities of the Whetstone Horizon In frames of the present thesis taphonomical and paleoecological processed were described in selected localities of whetstone horizon. Fossil plant assemblage known from the locality Štilec represents plant community buried in situ by volcanic ash after volcanic explosion (Pennsylvanian, Bolsov). Plant community exhibits relatively low diversity assemblage of herbaceous and subarborescent plants. This unique taphocoenose was interpreted as pioneer assemblage growing in partly drained lake. In the locality Ovčín the peat bog of Lower Radnice Seam was buried during the same volcanic eruption by volcanic ash. Up to now 5 excavations were recovered of the area of seats over 150 m 2 on two sites which are approximately 40 m distant from each other. In this area 27 morphotaxa of fossil plant was recorded. They represent 20 whole plants. Fossil plant remains represent fossil plant assemblage dominated by lycopod plants of planar (rheotrophic) swamp situated in narrow palaeovalley with active fluvial system. Second part of the thesis is focused on systematic descriptions of fossil plant taxa from localities of the Whetstone horizon. A monotypic genus Huttonia and species Huttonia spicata from Class Sphenopsids was emended. Further there were described...
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Cello Concertos by Josef Antonín Gurecky
Hamouz, Petr ; Maňourová, Lucie (advisor) ; Kapsa, Václav (referee)
The subject of concerts for cello composed by Josef Antonín Gurecký represents much unknown - for instance, circumstances under which the seven cello concerts were created (order, dedication), reasons to file and keep them in the archive of Wiesentheid, or dates of their creation; reasons for Gurecký's trips to Germany, and namely Dresden (where the Sonata for violin and a violin concert with a difficult violin part, probably dedicated to Johann Georg Pisendel, have been retained), and Wisentheid (cello concerts). I concentrate on all these issues in different chapters of my thesis in the extent which is proportional to the material found about Josef Antonín Gurecký. The material, however, do not seem to be numerous at this moment. The main focus (or focuses) of my thesis lies in the work with concert manuscripts, their processing and transcription into the contemporary notation, potential corrections of mistakes in manuscripts, and all issues that may contribute to using of this reprocessed music for the present concert performance.
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New Electrolytes for Modern Electrochemical Applications
Reiter, Jakub ; Mička, Zdeněk (advisor) ; Opekar, František (referee) ; Vlček, Antonín (referee)
1. Introduction Electrochemical and mechanical properties of polymer gel electrolýes have been intensively investigated since the introduction ofthe 1" generation of solid polyrrner electrolýes by M.Armand [1]. Their electrochemical application includes secondary lithium batteries, supercapacitors, chemical sensors and electrochromic devices. Wide application of the gel polyrner electrolytes is allowed due to the hrgher ionic conductivity compared with solid polyrner electrolýes and due to the higher safety properties in comparison with common liquid electrolytes. Organic methacrylate-based polymers are perspective materials for their low toxicity both of monomer and polymer forrn, when methyl methacrylate (MMA) is widely used in the dental praxis. Poly(methyl methacrylate) PMMA was used in electrochemistry for the frst time by Iijíma [2] and than either pure or in different polymer modifications including varlous copolymers [3, 4]. Aprotic solvents like sulpholane, organic carbonates, N,N- dimethylformamide, and formamide are usually incorporated in the polymer structure to form ternary electrolýe polymer-solvent-salt. PMMA polymer gel electrolytes with embedded particles of nanosized TiO2 [5], carbon [6] or proton-conductive membranes with different organic acids t7l oÍ orthophosphoric acid [8] were...
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Explanation and risk assessment of alien woody plants invasion in Central Europe by historical and ecological factors
Křivánek, Martin ; Pyšek, Petr (advisor) ; Prach, Karel (referee) ; Richardson, David M. (referee)
Conclusions The studies presented focus on the historical and ecological traits corresponding with the successful invasion process of alien woody plants in Central Europe. In regard to invasion biology, woody plant species are among the most problematic plant life forms and constitute a high proportion of the World's worst invasive species. The irreversible changes in ecosystems often caused by invasion of these species constitute one good reason for study. The second is the large amount of data available, especially on human influence and activity (such as the intensity of planting, residence time). The reason for studying alien woody species is also reflected in their ambivalence: on the one hand, the group is represented by the most serious invasive species, while on the other hand, there is still strong pressure to plant these species for timber, food and ornamental purposes. The native woody flora of the Czech Republic contains about 280 species. The exact number of alien woody species in not known. Based on different approaches and datasets, it has been estimated to be in the order of 4,300 species. Exact data is available for a representative sample of frequently-planted alien woody species that contains 1,691 species. An estimated 128 alien species have escaped from cultivation, of which about 17...
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Programmes of monitoring of bird occurrence and abundance as a source of ecological data
Mourková, Jindra ; Fuchs, Roman (advisor) ; Reif, Jiří (referee) ; Bejček, Vladimír (referee)
5 regionálních atlasech (Flousek & Gramsz 1999, Hromádko et al. 2005), umožňuje lépe zachytit proměnlivost výskytu a početnosti ptáků, která je daná mozaikovitostí studovaného území. Kromě údajů o prokázanosti hnízdění v jednotlivých kvadrátech síťových map přináší také odhad početnosti v celém území CHKO, charakteristiku výskytu a prostředí využívaného druhem na daném území a údaje o hnízdních hustotách v různých typech prostředí. Kvantitativní mapy pro jednotlivé druhy nejsou bohužel dosud zpracovány. SUMMARY OF THE THESIS In the thesis, regional data on bird communities were studied in terms of species richness and occurrence of bird species in dependence on habitat and, in case of wintering birds, also on climatic conditions. The regional grid atlas of Prague (Fuchs et al. 2002), records from Wintering waterbird census in Central Bohemia, own data on the breeding population of the Mute Swan in the Třeboň region and data from individual marking of Mute Swans provided by the Bird Ringing Centre of the National Museum were used as the sources of data on the occurrence and abundance of bird species. The thesis also includes a part of the text of the prepared Atlas of breeding distribution of birds in the Třeboň region. The first contribution (Mourková J., Fuchs R., Sedláček O., Janovský Z., Exnerová A.,...
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Characterization of electrophoretic separation systems,utilization of system peaks for determination of surfactant properties and optimalization of complex separation systems by the LFER model
Lokajová, Jana ; Tesařová, Eva (advisor) ; Coufal, Pavel (referee) ; Ševčík, Juraj (referee)
Conclusions o We have developď new method for CMC determination that is based on the measurementsof sysrem peaks eigenmobilities in capiiluy "t*o"oo"r*tr. The proposed method is moreprecise and eliminates specific systematic errors .o.*'n* when using some s*ndaťdmethods. The proposed method has U".n opti*i""a "o^ia,sysrcm peaks. ..Ý9 .r4. uE'tl UP.lmzeo considering intensities (amplitudes) of o The implementation of mice description ", ",".o".#'ÍÍ.',11Tffi :: jlTl.Ti#'ff ffiTr,"JT::,l:systems. Simulation prognrms curÍently allow user. to cď"ulate system eigenmobilities andeven to optimize the micellar separation systen. We h;\ *:ffi J:ffi.;: oÍ extended simulation o.o,*,",.u".il.;:T"T1'ffi ' ffill: We have clarified the mobi strength, which "uu,", .pri..ll,l?.jln.fi.r::ř""".J:"# peak due to the BGES ionic additional peak has "oo.a,.o in the electrophe.oror, ,oo**"r' As a consequence an :::::::::'*":u.'*..in.*oo.". identifi cation ", i"*,,.,"'ť"i:TT. *i:ajff:oeen possible using rhe set of different derecrion waveilil:" capirrary zone electrophoresis has been used to revear a structure and charge of nanoparticresin the recentry synthesized bulky porymer micelres ,n-'ltt".*, pH regions and to t3 characterize the effect of the PvP fraction added to PS.PMA on the final structure. ouÍ results have confirmed that...
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Modulation of body fat content by targeting the lipid metabolism of adipose tissue
Šponarová, Jana ; Kopecký, Jan (advisor) ; Konvalinka, Jan (referee) ; Drahota, Zdeněk (referee)
CONCLUSIONS 1. Induction of obesiý resistance in mice by transgenic expression of UCP1 in white fat can be explained by a metabolic switch ínadipocýes, due to depressíon oť celluiar energy charge, in situ activaÍion of AMPK, down- regulation ofadipogenic genes and increase in lipid oxidation. 2. AMPK cascade is involved in the fat depot-specific metabolic responses in various fat depots to starvation. Activation of the cascade occurred in epididymal but not in subcutaneous fat in mice. The activation of AMPK in adipocytes might represent an important mechanism by which body fat stores are regulated and may contributes to regional differences in the metabolic properties ofadipose tissue depots. Dietary EPA and DHA reduce development of obesity induced in mice by high fat diets, in part due to counteracting increase in tissue cellularity, particularly in epididymal íat.Low EPA/DHA ratio potentiates the anti- adipogenic efíect. Dietary EPA and DHA induce a metabolic shift in white adipose tissue by up-regulating genes for mitochondrial proteins, including their regulatory genes PGCIa and NRF-I, and increase B-oxidation while depressing lipogenesis, preferentially in the epididymal fat in the abdomen. 3. 4. J. 21
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Dental and Oropharyngeal Morphogenesis: Germ-layer Stability, Homology and Evolution.
Soukup, Vladimír ; Černý, Robert (advisor) ; Krylov, Vladimír (referee) ; Matalová, Eva (referee)
The vertebrate oropharyngeal cavity is a complex organ system housing food intake apparatus that is composed of hard- structured elements, the teeth. This apparatus is built upon mutual interactions between the epithelium and the underlying mesenchyme, which, however, take place only after the establishment of boundaries between the ectoderm and endoderm within this epithelium. Although possibly stereotypically positioned within the mandibular arch, our comparative morphogenetic survey identified that boundaries between ectoderm and endoderm are a result of different development in different vertebrate clades due to formative and constraining events taking place at early embryonic period. Dissimilar morphodynamics of ectoderm and endoderm are subsequently mirrored in the epithelial derivation of respective teeth in such a way that, e.g. in the Mexican axolotl, the oral teeth eventually display ectodermal, endodermal and ecto- endodermal derivation. Moreover, the ecto- endodermal boundary could have a tooth- inductive role, ...
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New findings in Taxonomy and Chemistry of the Genus Lepraria Stereocaulaceae, Lichen-forming fungi)
Slavíková, Štěpánka ; Liška, Jiří (advisor) ; Bérešová, Anna (referee) ; Sipman, Harrie J.M (referee)
I 3. SulruRny oF THEMArNREsuLTsoF THETHEsts The submittedthesis includes seven papers discussing new findings in morphology, chemistry,eco|ogyanddistributionofthegenusLepnia andsomeother|ichens.HereinaÍter themainÍesu|tscomingoutofthesepapersaÍelisted. í. During own chemotaxonomicresearch oÍ the genus Leprarla, severaI species newforthesciencehavebeendescribed_ LeprariacelaÍaS|aviková,L. granulataS|aviková. L.humida S|avíková& orange, and L. ťoensberyianaBayerová& Kukwa (Bayerováet a|. 2005,Slaviková-Bayerová& Fehrer2007,S|avíková-Bayerová& orange2006).Furthermore, othertaxaprovisionallynamedLepnria sp. BG, L. sp. G, and L. sp. H havebeen introduced, whose taxonomicstatusis not yet entirelyclear.In addition,therehas been founda taxon Leprariasp.,whichis chemica||ysimilarto the speciesL. atlanticaorange,difíeringhowever in morphology(S|avíková-Bayerová2006).The taxon is either a yet undescribedspecies or an extremeform of L. atlantica.The examinalionof more materialto clarifythe identity of thesetaxawillbe required. 2. ln the species L. atlantica,L. celata,L. jackii, L. granulata,L. humida,L. sylvicolaOrange, andL. ťoensbe4giana,the presence of hyphae gÍowingoften into cracks and cavities oÍthesubstratumWith the tendencyto penetrateit was found out (s|avíková.Bayerová & FehÍeÍ2007, S|aviková.Bayerová& orange...
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