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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.
21

Vektory, šíření a genetická variabilita patogenu račího moru v oblastech, kam byl zavlečen / The crayfish plague pathogen Aphanomyces astaci in its introduced ranges: vectors, introduction pathways, genetic variation and host-pathogen interactions

Mrugała, Agata January 2016 (has links)
- ABSTRACT - The crayfish plague pathogen, Aphanomyces astaci, is responsible for substantial declines and local extinctions of native European crayfish populations. As a consequence, the pathogen is now listed among 100 world's worst invasive alien species. The spread of A. astaci is greatly facilitated by its natural hosts, North American crayfish, that thanks to a long co-evolutionary history with the crayfish plague pathogen evolved efficient defence mechanisms. In contrast, European, Australian and Asian crayfish species are highly susceptible to this disease agent. However, progress of A. astaci infection in native European crayfish was observed to differ between distinct pathogen strains, indicating variability in their virulence. Indeed, we demonstrated a relationship between patterns in crayfish immune response and A. astaci virulence in an experimental infection involving the European noble crayfish and three differently virulent crayfish plague strains. The European continent is currently inhabited by at least eight North American crayfish species. The carrier status was confirmed in six of them, including also Orconectes cf. virilis occurring in the Netherlands and the UK. In this country, we detected Aphanomyces astaci presence in some populations of the non-indigenous crayfish species as well...
22

Experimentální vyhodnocení role biotických interakcí při stanovování zásobníku druhů společenstev / Experimental assessment of the role of biotic interactions in community species pool delimitation

ŠVAMBERKOVÁ, Eva January 2015 (has links)
Seed addition experiment was conducted on the moisture gradient with aim to demonstrate that many species not accounted by current measures of species pools in a site should be included because they are in fact able to establish successfully if biotic filter is removed. Transplant experiment was established to compare the sensitivity of seedling recruitment and survival of transplants in the field. Recruitment of seedlings in field was observed and compared with germination of seeds under different chilling treatments in laboratory.
23

Tvarosloví a slovní druhy v českých gramatikách francouzštiny / Flexional morphology and Parts of speech classification in Czech grammars of French

PEROUTKOVÁ, Jitka January 2010 (has links)
This work is divided into three major parts. The first one deals with parts of speech themselves {--} with what they are, with the criteria for sorting them and finally it presents the history of linguistic theories, related to the parts of speech. The second one presents the progress and results of bibliographic searches, during which we were looking for czech grammar books, dealing with French. The third part presents the actual analysis of manuals, that were found, focusing on the classification of the parts of speech.
24

Právní úprava ochrany volně žijících druhů ptáků / Legal regulation of protection of wild bird species

Kubešová, Jana January 2021 (has links)
Legal regulation of protection of wild bird species Abstract This thesis deals with legal regulation of protection of wild bird species at the international, European and Czech level. The aim of the thesis was to provide an overview of legal regulation of protection of wild bird species, and to evaluate whether this legal regulation is an effective means of achieving objectives which led to its adoption. The thesis consists of an introduction, three main parts and a conclusion. The first part of the thesis describes protection of birds in international law. In this part of the thesis there are first introduced international organizations important for protection of birds, in particular International Union for Conservation of Nature and BirdLife International, and then in the author's opinion the most relevant international conventions to protection of birds, namely the Ramsar Convention, the Bonn Convention, the Bern Convention and the Convention on Biological Diversity. The following second part of the thesis focuses on protection of birds in European law. In this part of the thesis legal regulation of protection of wild bird species in Directive 2009/147/EC (the Birds Directive) is described in detail including the related case law of Court of Justice of the European Union. The author pays attention...
25

Statistická analýza katalogů přirozené a indukované seismicity / Statistical analysis of natural and induced seismicity catalogues

Mazanec, Martin January 2017 (has links)
The main goal of this thesis is to analyze the statistical properties of seismic catalogues of natural and induced seismicity, identify similarities and differences. We compare statistical temporal and magnitude information contained in different types of earthquake catalogues. Six seismostatistical criteria used for identification of natural swarms and mainshock- aftershock earthquake sequences are applied to 10 different catalogues of natural and induced seismicity. We did not find a method to reliably distinguish between natural and induced seismicity based only on temporal and magnitude information contained in catalogues. We show that induced seismicity catalogues are similar to natural earthquake swarms. We report how the set of 6 criteria presented here can be used for distinguishing between mainshock-aftershock sequences and swarm seismicity. We also show that none of the tested criteria can be used independently for distinguishing between different types of seismicity.
26

Rozlišení různých druhů vajec pomocí hmotnostní spektrometrie / Differentiation of different types of eggs by mass spectrometry

Švárová, Markéta January 2021 (has links)
The aim of the diploma thesis was to distinguish bird species based on the expected different protein composition of eggs and their individual components using mass spectrometry. The obtained results could be possibly used to identify the animal origin of egg materials used in works of art. For the research, components of the eggs (yolk, egg white and their mixture) of nine available bird species were collected and dried - pheasant (Phasianus colchicus), domestic goose (Anser anser domesticus), domestic duck (Anas platyrhynchos domesticus), muscovy duck (Cairina moschata), chicken (Gallus gallus f. domestica) - four different specimens, Japanese quail (Coturnix japonica), pampas rhea (Rhea americana), red ore (Alectoris rufa), speckled guinea fowl (Numida meleagris). The samples were digested by the enzyme trypsin and prepared using ZIP-TIP for the next measurements by MALDI-TOF (Matrix-Assisted Laser Desorption / Ionization - Time of Flight) mass spectrometry. The obtained data were evaluated by Principal Component Analysis (PCA). The used method showed that the most bird species can be distinguished by yolks (with an approximately 95% success rate) and more than half of the species by egg white proteins (success rate 83%) and by the egg white and yolk mixtures (success rate 80%). Two samples of...
27

Objasnění druhových hranic v sekci Restricti rodu Aspergillus na základě multigenové fylogeneze a analýzy fenotypu / Species limits within Aspergillus section Restricti inferred from multiple gene phylogenies and phenotype analysis

Sklenář, František January 2016 (has links)
Section Restricti is one of the last sections of the genus Aspergillus that hasn't been revised in the modern taxonomic era. All species are osmophilic, have simple morphology and they are mainly important because of the food, feed and seed spoilage, some of them also have negative influence to the indoor air. The section consists of seven species according to the last taxonomic revision from 2008 based only on molecular data. It currently consists of six asexual and one homothalic species. 126 isolates from the section coming from four continents were studied in this thesis, including ex-type strains. Revision of the section was carried out combining molecular phylogenetic analysis and conventional taxonomic methods. Modern methods of species delimitation based on multispecies coalescent model were used for the phylogenetic reconstruction. From the conventional methods analysis of morphology (macro- and micromorphology including scanning electron microscopy) and physiology (ability of growing in osmotic gradient and several different temperatures) was performed. Apart from the seven known species, eight new undescribed species were discovered. Majority of the new species belongs to the Aspergillus penicillioides species complex. Key words: Aspergillus restrictus, osmophilic fungi, species...
28

Změny lesní vegetace Šumavy a jejího podhůří během druhé poloviny 20. století / Forest vegetation changes in the Bohemian Forest during the second half of 20th century

Prach, Jindřich January 2012 (has links)
Long-term forest vegetation changes were studied in the Bohemian Forest and its foothills. New vegetation relevés were taken at sites of typological plots established by forest engineers between 1955 and 1980. Data from 158 semi-permanent plots were analysed using modern statistical methods. The data show significant changes and homogenization of the vegetation. Ellenberg indicator values indicate eutrofication. Repeated measurements of soil pH suggest acidification, but the interpretation of these data is complicated by methodological problems. The forests under study exhibit high spatial variability. No main prevailing trend in vegetation changes was found. The changes are considered to be related to sulphur and nitrogen deposition and forest management. The influence of increasing age of forest stands seems to be unimportant. Discussed are not only vegetation changes and their possible causes but also the possibilities and limitations of using such old forestry data in botanical and ecological studies.
29

Početnost nepůvodních druhů vrubozobých ptáků v Evropě / Numbers of non-native waterfowl species in Europe

Hodková, Veronika January 2012 (has links)
The Thesis is treating the spreading of non-native waterfowl species into new ecosystems and factors, which influence that process. The impact of selected eco-geographic characteristics on the species diversity and on the numbers of non-native waterfowl individuals was analyzed on the results of the International Waterbird Census. Further, the influence of those characteristics on the numbers and population trends of selected 11 species of the Anatidae family in 17 European countries was assessed. The highest non-native waterfowl species diversity was recorded in countries of the Atlantic coast, i.e. France, Germany, the Netherlands, Belgium and also Switzerland. The main positive influence on their numbers makes the density of population and species diversity of wintering waterfowl. As to the number of non-native species individuals the main impact is produced by both, species diversity and the given latitude, too. It means that the largest number of individual exist in northern countries - Great Britain, Sweden, Germany and the Netherlands. Similar main influences have been traced with the family Anatidae, too, which have received special attention in the analysis, as it shows the highest number of non- native species. As to the main eco-geographic characteristics, having impact on the growth or...
30

Hledání struktury vět přirozeného jazyka pomocí částečně řízených metod / Discovering the structure of natural language sentences by semi-supervised methods

Rosa, Rudolf January 2018 (has links)
Discovering the structure of natural language sentences by semi-supervised methods Rudolf Rosa In this thesis, we focus on the problem of automatically syntactically ana- lyzing a language for which there is no syntactically annotated training data. We explore several methods for cross-lingual transfer of syntactic as well as morphological annotation, ultimately based on utilization of bilingual or multi- lingual sentence-aligned corpora and machine translation approaches. We pay particular attention to automatic estimation of the appropriateness of a source language for the analysis of a given target language, devising a novel measure based on the similarity of part-of-speech sequences frequent in the languages. The effectiveness of the presented methods has been confirmed by experiments conducted both by us as well as independently by other respectable researchers. 1

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