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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.
61

Morfologická plasticita chrpy luční \kur{(Centaurea jacea L.).} / Morphologic plasticity of \kur{Centaurea jacea.}

KARÁSEK, Jakub January 2010 (has links)
Morphological plasticity of brown knapweed (Centaurea jacea L.) was examined. South bohemian populations of subsp. jacea were compared to plasticity in larger area. The plasticity of local population overlaps with both subspecies. The correlation between abiotical factors and determination characteristics were found. Molecular survey using ISSR method shows no difference between subspecies. The final resolution of subspecies existence will be questioned in following study.
62

Morfologicko-genetická studie populací mořského plže \kur{Hexaplex trunculus} ze Středozemního moře / Morphologic-genetic study of populations of salt-water gastropod \kur{Hexaplex trunculus} from Mediterranean sea

MACÍK, Jiří January 2011 (has links)
Variability in genes and shell shape of salt water gastropod Hexaplex trunculus (Linné, 1758) was compared among the samples from three Croatian coastline localities, four localities on Greek island Lefkada and two localities from south France coastline in total number of 464 specimens. Genetical criteria were not found for separating individual populations. No variability were found in 683 bp long fragment of gene for michondrial cytochrome c oxidase subunit one (COI). Differences among populations were not significant, even in conection of my data with the data of recent portuguese study (sequences from GenBank). Differences among populations were found by the geometric morphometric method. Based on these results, morphotypes for certain habitats were determined. During the study, high level of tributyltin (TBT) pollution in the Mediterranean sea causing sexual malformation called imposex phenomenon, was proved in this species of gastropod.
63

Systematika a proměnlivost zdravínku jarního Odontites vernus (Bellardi) Dumort. v České republice / Systematics and variation of Red Bartsia, Odontites vernus (Bellardi) Dumort. in the Czech Republic

BAĎUROVÁ, Tereza January 2012 (has links)
The Master's thesis studied the Odontites vernus group in the Czech Republic. The group was presented by two different taxa based on the seasonal types and the ploidy levels: an early flowering tetraploid Odontites vernus subsp. vernus (2n = 4x = 40) and a late-flowering diploid Odontites vernus subsp. serotinus (2n = 2x = 18). Plants from 33 populations were sampled for measuring the ploidy level and 27 morphological characters for morphological analysis. Two ploidy levels were confirmed in the Czech Republic and a new late flowering tetraploid taxon (2n = 4x = 40) was found. The three taxa were separated from each other based on the seasonal variation, ploidy level, morphology and ecology.
64

Genetická variabilita v populacích chrastice rákosovité (Phalaris arundinacea L). / Genetic variation in populations of reed canarygrass, \kur{Phalaris arundinacea} L.

KÁVOVÁ, Tereza January 2013 (has links)
The spread of invasive plant species in natural habitats has become a worldwide problem with negative environmental and economic impacts. An increasing number of invasive organisms are responsible for adverse environmental and economic impacts worldwide, including species extinction, crop failures, reduced water supply, and damage to industrial infrastructures (KERCHER et al., 2007). Phalaris arundinacea L. is widespread throughout the world, except Antarctica and Greenland. Center of diversity of this genus is in the Mediterranean. Members of the genus Phalaris occurs in moist habitats from lower to alpine altitudes (ANDERSON, 1997). Phalaris has a plethora of uses. Its most frequent use is as the root wastewater treatment plants. Phalaris grown as feed for livestock and is also used as an ornamental grass. Phalaris have recently received a lot of attention as a new biomass source for the production of renewable energy in USA. In recent years there has been a massive spread of P. arundinacea across North America (currently occurs in 43 states) and Canada (ZEDLER & KERCHER, 2004). Phalaris represents a significant threat to its original wetland vegetation and is classified as a harmful agens in nine state of U.S. states (LAVERGNE & MOLOFSKY, 2004). It is believed that these aggressive population have European origin.
65

Genetická variabilita a fylogeografie mšice zhoubné \kur{Diuraphis noxia} (Aphididae) / Genetic variability and phylogeography of Russian wheat aphid, \kur{Diuraphis noxia} (Aphididae)

SATTRANOVÁ, Anna January 2013 (has links)
Genetic analysis of 433 samples of serious crop pest aphid Diuraphis noxia was conducted with the use of 8 microsatellites loci. Statistical analysis revealed sexual reproduction of D. noxia in temperate regions. The linkage disequilibrium was detected because of the excess of heterozygotes. These results support the theory of RNDr. Starý about the invasion of D. noxia to American continent via states of North Africa, Spain and France.
66

Variabilita provedení atletických disciplín staršího žactva / Technique variability of athletic discipline old school athletes

Hykeš, Radek January 2017 (has links)
Title Technique variability of athletic discipline old school athletes Objectives The aim of the work was to find out how and to what extent the technical variability of the athletic disciplines in the category of the older stage in the execution from the place or from the short start, compared to the whole acceleration version, thus at a higher speed. Methods The thesis was conceived as a theoretical-empirical survey where quantitative and qualitative assessment of the level of fitness and technical readiness of probands was used Results The best rating, and hence the high level of variability, has tested No. 5, which has reached 0.71, pointing to excellent discipline technique even at higher speeds. This is followed by Test No. 4, which has reached 0.40. Testing shows that these two tests are at the same time the best in motor tests where they achieve above-average results, so we can state that the one who is at a higher level of fitness is better able to handle athletic disciplines and adds more speed. The test value 6 also reached the value of 0.20, which also means better technical performance at higher speed. The other tests were always worse in the higher-speed version, worst-tested 3, which deteriorated by 0.72. The other tests worsened by about 0.5. Key words Athletics, older school,...
67

Taxonomická studie okruhu terčovníku Physconia muscigena / A taxonomic study of Physconia muscigena group

Starosta, Jakub January 2016 (has links)
The principal goal of my study was to find if ecologically and chemically different populations of lichens in the Physconia muscigena (Ach.) Poelt group belong to several species or a single one. This study focused on the molecular and chemical investigations of mostly European and Canadian populations. I use sequence data from three genes (ITS rDNA, mtSSU rDNA and TEF1) for the reconstruction of phylogenetic trees. I investigate phylogenetic relationships among the closely related species P. muscigena, P. bayeri, P. rossica, and P. isidiomuscigena. Also, I wanted to detect any possible geographical or ecological trends among chemotypes and haplotypes. As an additional goal I checked the recent localities of P. muscigena in the Czech Republic for valorising its conservation status. Results show that: (1) sequenced data of ITS rDNA and TEF1 show high intraspecific variability in P. muscigena samples. This genetic variability does not correlate neither with geographical distribution nor thallus chemistry; (2) P. bayeri is synonymous with P. muscigena; (3) some samples P. muscigena contain new undetermined secondary metabolite, (4) Physconia muscigena has only three recent localities in Czech Republic. Key words: Physconia muscigena, Physconia bayeri, infraspecific variability, taxonomy, TEF1, ITS...
68

Genetická variabilita rodu Alburnoides v Ázerbájdžánu / Genetic variability of the genus Alburnoides in Azerbaijan

Omelchenko, Dmytro January 2016 (has links)
The Caucasus region is characterized by high rate of endemism and taxa richness of fishes. Azerbaijan is a country situated on the border between Europe and Asia with rivers flowing in the Caspian Sea. Natural environment of this country is represented by various habitats with diverse ichthyofauna. This region is very attractive for biogeographical studies because it lays on the border of two different ecoregions. Even on the modern stage of scientific cognition, there is still lack of data about freshwater fishes from that region. Spirlins or rifle-minnows (Alburnoides Jeitteles, 1861, Actinopterygii, Cyprinidae) is a genus of small freshwater fishes and it has been chosen as a focus of this thesis because of numerous reports of new species from surrounding countries. The presented thesis is one of the seldom molecular studies trying to reveal the taxonomical situation within the genus Alburnoides, describe the phylogenetic relationships between geographically isolated populations, and provide biogeographical implications for fishes in the Caspian Sea river basins. Both mitochondrial (cytochrome b, cytochrome oxidase subunit I) and nuclear (RAG1, rhodopsin) markers were used in the study and the Maximum Likelihood, Maximum Parsimony and Bayesian phylogenetic analyses were performed. Further, the...
69

Variabilita pohřební výbavy ženských hrobů ve středním laténu na území Čech / Variability of grave goods in female burials in the middle La Téne period in Bohemia

Pršalová, Tereza January 2015 (has links)
Presented diploma thesis is devoted to the analysis of the female graves of the La Tène period in Bohemia, more particularly it relates to quantity, material and placement of every objects of the grave goods. Observed variability indicates time, regional and in some mesure social differences which influenced the composition of the grave set. Within the comparison, the graves from Moravia, Slovakia and Austria have been also taken into consideration.
70

Vliv rychlosti chůze u pacientů s periferní vestibulární lézí na schopnost udržení přímého směru chůze / The effect of locomotion speed on linear path integration performance in patients with peripheral vestibulopathy

Petříčková, Kristina January 2017 (has links)
DIPLOMOVÁ PRÁCE 2017 Kristina Petříčková Abstract This diploma thesis is focused on the effect of peripheral vestibular dysfunction and locomotion speed on the ability to walk a straight path. Nineteen patients with chronic peripheral vestibular dysfunction and twenty healthy volunteers participated in this study. The angle deviation from 10 meters long straight path while walking with eyes closed was measured, using three locomotion speeds: slow, preferred and fast walking. Tandem gait with eyes opened and closed was also tested for maximum of 15 steps. There was no statistical difference between group of patients and the control group in any of the tested gait speeds. Within both groups, there was a significant difference between deviations in different gait speeds, specifically between slow and preferred speed and between slow and fast speed. There was a statistical difference in tandem gait between patients and controls when walking with eyes closed. It has been shown that locomotion speed effects magnitude of deviation in path integration task. However, slow walking with eyes closed did not quantitatively differ in chronic compensated patients and healthy subjects. Tandem gait has been proven to be more sensitive with overall obvious difference, although in individual tandem gait testing it is...

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