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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.
111

Morfologie a evoluce vybraných skupin Palaeodictyopterida (Insecta: Palaeoptera) / Morphology and evolution of selected groups of Palaeodictyopterida (Insecta: Palaeoptera)

Pecharová, Martina January 2017 (has links)
Palaeodictyopterida is remarkable insect superorder, which formed a significant part of the diversity of upper Palaeozoic insects, but disappeared by the end of the Permian. The main synapomorphy of the superorder is the piercing-sucking mouthparts in the form of a rostrum consisting of five styles. This rostrum was probably used to pierce on plant tissue and for the juice sucking. The same type of mouthparts shared by adults was present also in larvae of Palaeodictyopterida. The external copulatory organs of the superorder members was also showed some morphological interests. The male genitalia consist of a pair of gonostyli and two penial lobes, similarly to the genitalia of recent Ephemeroptera. The female genitalia of Palaeodictyopterida are developed in a form of the ovipositor that can be compared with the endophytic ovipositor of some recent Odonata. This morphological features support placement of Palaeodictyopterida as sister group of Odonatoptera + Panephemeroptera. The main aim of the work was to describe new representatives of the order Megasecoptera, the second largest group of Palaeodictyopterida. Wing venation of Megasecoptera exhibits a reduction of the longitudinal and transverse veins in comparison with the order Palaeodictyoptera. Other body structures were examined mainly in the...
112

Co stojí za evoluční explozí diverzity terestrických vodomilů? / Understanding the biodiversity boom in terrestrial hydrophilid beetles

Arriaga Varela, Emmanuel January 2019 (has links)
The research contained in this thesis explores the phylogenetic systematics, taxonomy, evolution and biogeography of tribe Megasternini (Coleoptera: Hydrophilidae: Sphaeridiinae). Megasternines are an oustandingly diverse group of terrestrial water scavenger beetles with almost 600 described species and probably up to 1,000 species in total. Its species can be found in a wide array of habitats with abundant decaying material like humid leaf litter, dung, rotten cacti, beach wrack, flowers, etc. The specific and ecological diversity as well as their global distribution makes Megasternini an interesting model group for the understanding of processes underlying the diversification, biogeography and evolution of beetles. The scientific part of the thesis contains seven papers: three published, one accepted, one submitted and two manuscripts. Chapters 1-4 are focused on the taxonomy of selected groups. These chapters aim to cover a variety of cases in terms of biogeography (the Greater Antilles, northern Neotropics, Africa and Southeast Asia), ecology (species associated with leaf litter, dung, flower and rotten cacti) and different taxonomic scenarios. One new extant genus and eight new extant species are described in these chapters. Chapter 5 is a revision of all known hydrophilid fossils from Baltic...
113

Role auxinu u streptofytních řas / The role of auxin in streptophyte algae

Schmidt, Vojtěch January 2021 (has links)
The phytohormone auxin is an important morphogen with an essential role in the development of land plants, where mechanisms of its action are well described. However, its role in green algae is poorly understood. Land plants are part of the phylum Streptophyta together with six closely related groups of predominantly freshwater green algae (charophytes). So far, the knowledge about the evolutionary origins of auxin action mechanism is mainly based on genomic information, and much less on experimental findings. In this work, the presence of auxin, its precursor, and catabolism products were shown in representative species of charophytes with varying levels measured compounds both produced endogenously and into the culture media. Thus, we gained a comprehensive insight into the possible strategies of auxin homeostasis across the non-land plant streptophytes. Also, an effect of exogenous auxin on the cell morphology and culture growth of the desmid Closterium was investigated. Image analysis of IAA-treated cells revealed a rather pleiotropic effect on cell morphology. The culture growth was inhibited by IAA. Additionally, IAA induced malformations in cell shape, and the extent of this phenomenon across individual cultures was dependent on the culture growth status. Lastly, we optimized the method of...
114

Syntéza feroelektrických a dielektrických keramických kompozitních materiálů / Synthesis of ferroelectric and dielectric ceramic composite materials

Čípová, Eva January 2013 (has links)
The topic of the thesis is preparation of ferroelectric and dielectric composite materials, particularly the work deals with the preparation of barium strontium titanate. In the theoretical part the possibilities of BST synthesis and its processing are described. The experimental part deals with precipitation synthesis of barium strontium titanate. Prepared powders were characterized in terms of morphology and phase composition. Further, pressureless sintering and hot isostatic pressing (HIP) were used for preparation of dense ceramics. Pure BST powders, that were formed and sintered, were prepared by sol-gel precipitation synthesis. The highest density was reached by slow sintering cycle (slow increase of temperature and delay during sintering) and sintering by HIP.
115

Tvařitelnost tenkých ocelových plechů s povrchovou úpravou eloxovaného hliníku / Formability of Thin Steel Sheets Coated with Anodized Aluminum

Hušek, Martin January 2012 (has links)
Thesis deals with the design of the technological process of anodic oxidation (creating elox coating) on aluminium film in the system steel-aluminium-elox, with the findings of characteristics of this system, comparing with the contemporary knowledge and practical utilization of this system in practice. My thesis in the teoretical part describes creating of anodic oxidation (elox coating) and the process of bending and stretching the sheet. Theoretical aspects of interaction among elox finish, process of bendings and process of stretching are implemented in the experimental part and they are supported by identified knowledge and results. The practical part is focused on improving adhesion, designing and constructing a multifunctional bending product for testing resistance of the finish applied on a tested product. Under the terms of determination distributing deformation and tension in bended coated plate, this plate is tested by statistic analysis with the help of the Finit Element Method (FEM) in the programme ANSYS. The experimental part compares discovered results of each experiment in the system steel – aluminium – elox with the results of aluminium plates with elox finish, stainless plates and steel plates with aluzinc.
116

Ptačí schistosomy a cerkáriová dermatitida v České republice: rozšíření, druhová diverzita a faktory ovlivňující jejich výskyt / Avian schistosomes and cercarial dermatitis in Czech Republic: distribution, diverzity and factors influencing their occurrence

Pokrupová, Zuzana January 2021 (has links)
Cercarial dermatitis (CD) is manifested as a strong itchy rash that usually occurs after bathing in the natural water bodies where it makes recreation uncomfortable. As a consequence, the natural swimming areas and be closed because of inconvenient water quality, what subsequently leads to the financial losses. The infection can also affect people working in the natural water bodies as lifeguards (at the natural swimming areas), people monitoring water organisms or water quality etc.). Nowadays, CD in Czech Republic occurs more frequently than in the past. For this reason, the topic of avian schistosomes and CD is very attractive not only for scientists, but newly also for employees of hygienic stations and health institutes. Based on the Act No. 258/2000 Coll. on protection of public health and related executive Decree No. 238/2011 Coll. approved this year their duty will be regular monitoring of official natural swimming areas for causative agents of CD. For the comprehensive overview about the occurrence of the avian schistosomes and CD, up to now, at the localities in the Czech Republic the specialized overview map with the marked catches of avian schistosomes and CD was created in the program ArcGIS Online. This map was made with use the records obtained from the scientific articles, final...
117

Výuka gramatiky ruského jazyka v českých učebních souborech pro úroveň B1 v porovnání s požadavky Standardu pro výuku ruštiny jako cizího jazyka / Teaching grammar of Russian language in Czech learning resources for level B1 compared to the requirements of the Standard for teaching Russian as a foreign language

Mrázková, Andrea January 2021 (has links)
This diploma thesis deals with the grammar curriculum of Russian language in the Czech teaching resources for B1 level and compares it with the requirements of the Standard for teaching Russian as a foreign language. The theoretical part of the thesis defines terms related to grammar; it describes and compares Czech and Russian curriculum documents and concerns with the Russian grammar teaching in the communicative approach. The last chapter of this part discusses the role of a teaching resource in the teaching process, the selection of such a resource and the description of individual resources for B1 level. The practical part presents the results of the content analysis of the teaching resources with respect to their minimum required grammar, which is first described individually for each resource and then compared with the requirements of the Standard for teaching Russian as a foreign language. Afterwards, the results are clearly summarized. KEY WORDS: minimum required grammar, morphology, syntax, teaching grammar, positive transfer, negative transfer, analysis
118

Bionika v architektuře (strom jako inspirační zdroj) / Bionics in architecture (tree as the source of inspiration)

Šáchová, Irena Unknown Date (has links)
The work deals with nature prefigurations, which can be used in architecture. The first part is concerned with the bionics in architecture in general. There are introduced all available pieces of knowledge falling within this branch. The second part is focused on the nature prefiguration – tree. The tree was analyzed from different points of view. Suitable principles, which were found, were transformed to the field of architecture. On the basis of children's drawings the changing approach to “tree as a home” during adolescence was charted. The work can serve as a comprehensive supporting document for study of bionics for students of architecture and architects and also for the general public. The work should point out that nature is our great standard for any activity.
119

Role metabolismu nukleotidů při vývoji kolonií Saccharomyces cerevisiae / Nucleotide metabolism in the development of Saccharomyces cerevisiae colony

Dvořáková, Markéta January 2014 (has links)
Yeasts are unicellular microorganisms which are able to form colonies. The morphology of colonies is characteristic for the strain and differs according to particular growth conditions. Saccharomyces cerevisiae colonies are able to produce volatile ammonia which functions as a signalling molecule alarming nutrient depletion (PALKOVÁ et al. 1997). Changes in gene expression, metabolism and ammonia production occur during the development of giant S. cerevisiae colonies. Genes with changes in expression have been identified to be involved in ammonia transport, amino acid metabolism and also in nucleotide metabolism. Genes, whose deletion may affect the induction of ammonia production have been described (ČÁP et al., 2010), (VÁCHOVÁ a PALKOVÁ 2005), (PALKOVÁ et al. 2002). This work is focused on studying of an impact of deletions of selected genes involved in nucleotide metabolism, as well as of changes in extracellular concentrations of different bases on growth, morphology, ammonia production, cell morphology and differentiation of giant S. cerevisiae colonies. S. cerevisiae strains producing Gfp-tagged proteins (Ade4p-Gfp, Adk1p-Gfp, Urk1p-Gfp, Fcy2p-Gfp, Fur4p-Gfp, Fcy22p-Gfp) have been constructed and analyzed. Development of S. cerevisiae giant colonies with deletions of selected genes (ADE5,7,...
120

Možnosti pojetí výuky morfologie listů na 2. stupni ZŠ / Options of Approach to Teaching of Morphology of Leaf at Lower Secondary School

Němečková, Linda January 2015 (has links)
1 ABSTRACT The thesis deals with the options of approach to teaching leaf morphology at lower secondary schools from both theoretical and emprical point of view. The empirical part is then verified on-site within the teaching process. The theoretical part is dedicated to the topic of leaf and particular aspects of the teaching process. The empirical part at first attempts to conduct a survey of the methods and organization forms of teaching applied at particular lower secondary schools within the teaching of leaf morfology. Afterwards, it analyses selected textbooks used for teaching biology. Next part describes suggested methods and organization forms of teaching applied less frequently during the education. The second goal of the thesis is to put in practice the methods and organization forms of teaching within an educational experiment. Afterwards, a didactic test is used at representative schools to verify the efficiency. At the end of the thesis, the results of the following are presented: the observation of teaching leaf morphology, the analysis of the biology textbooks content, and the didactic test. The results of the didactic test demonstrate the extent to which the skills and knowledge of the students are effected by the methods and organization forms of teaching applied within the educational...

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