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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.
41

Alopatrická evoluce u kaloňů rodu Rousettus: od populační a krajinné genetiky k fylogeografii / Allopatric evolution in rousettine fruit bats: from population and landscape genetics to phylogeography

Stříbná, Tereza January 2018 (has links)
Population structure, biogeography and phylogenetic relationships of the fruit bat genus Rousettus have been studied in Africa and adjacent regions. The current population patterns of rousettine fruit bats in the Old World are influenced by several environmental attributes, namely the topography, climate and land cover. These variables are mirrored in fruit bat plesiomorphies related to the ecological niche of tropical flying frugivore, as well as apomorphies of rousettines including echolocation ability, roosting in caves and dispersal capacity in open landscapes with discontinuous tree cover. Phylogenetic relationships among species and subspecies of the genus have been indicated and confronted with the existing colonization scenarios. Insular populations (including habitat islands within desert oases) show frequent genetic differentiation from their mainland relatives suggesting successful founder events after traversing stretches of unsuitable habitats. Genetic differentiation evolving in less distant islands suggests involving behavioural mechanisms maintaining cohesion of isolated demes as site fidelity and natal habitat-biased dispersal. In sub-Saharan mainland Africa within the large range reaching from the southern border of Sahara to Cape Peninsula, Rousettus populations share a...
42

Ochranářská genetika vlka obecného a levharta sněžného: vliv krajiny na mikroevoluci populační struktury / Conservation genetics of grey wolf and snow leopard: effect of landscape attributes to the population structure

Benešová, Markéta January 2018 (has links)
Landscape genetic approaches allow to study effects of landscape to population microevolution. Landscape can influence gene flow even in large carnivores with good dispersal ability. Understanding the influence of landscape to the gene flow between populations is crucial for species conservation, especially in the species with low population densities. Aim of the study was to describe genetic structure of the grey wolf (Canis lupus) and snow leopard (Panthera uncia) in selected areas and to determine the influence of the landscape features on observed structure. Non-invasive genetic samples of snow leopard from Nepal were analysed, as well as invasive and non-invasive samples of grey wolf from Central Europe. Population structure was determined a posteriori using Bayesian clustering approaches that integrate genetic and geographical data, and compared to landscape connectivity models. Population structure of snow leopards is mostly influenced by human presence and presence of frequented roads, which represent a substantial dispersal barrier. Habitat suitable for this species is greatly restricted by altitude, however, during dispersal they are able to overcome areas with higher elevation than what is optimal for them. Pronounced genetic difference was found between central European and Carpathian...
43

Alopatrická evoluce u kaloňů rodu Rousettus: od populační a krajinné genetiky k fylogeografii / Allopatric evolution in rousettine fruit bats: from population and landscape genetics to phylogeography

Stříbná, Tereza January 2018 (has links)
Population structure, biogeography and phylogenetic relationships of the fruit bat genus Rousettus have been studied in Africa and adjacent regions. The current population patterns of rousettine fruit bats in the Old World are influenced by several environmental attributes, namely the topography, climate and land cover. These variables are mirrored in fruit bat plesiomorphies related to the ecological niche of tropical flying frugivore, as well as apomorphies of rousettines including echolocation ability, roosting in caves and dispersal capacity in open landscapes with discontinuous tree cover. Phylogenetic relationships among species and subspecies of the genus have been indicated and confronted with the existing colonization scenarios. Insular populations (including habitat islands within desert oases) show frequent genetic differentiation from their mainland relatives suggesting successful founder events after traversing stretches of unsuitable habitats. Genetic differentiation evolving in less distant islands suggests involving behavioural mechanisms maintaining cohesion of isolated demes as site fidelity and natal habitat-biased dispersal. In sub-Saharan mainland Africa within the large range reaching from the southern border of Sahara to Cape Peninsula, Rousettus populations share a...
44

Y chromosomální charakteristika současné vesnické populace na Klatovsku / Y Chromosomal Characteristics of the Modern Rural Population in Klatovy Region

Doležalová, Veronika January 2015 (has links)
Usage of genetic markers in non-recombining part of chromosome Y has been shown as a eligible tool for a study of history, diversity and migration of population. Applicable markers of chromosome Y are SNP and STR polymorphisms. There were collected 53 unique samples of DNA as a object of this work from unrelated origin males from 9 villages around Klatovy. Samples have been analyzed and its values have been determined by using the 17 STR markers by AmpFLSTR® Yfiler® Direct Kit. In total I have observed 7 different haplogroups. I have resulted samples from villages around Klatovy and they were analyzed by AMOVA. I have compared samples with the surrounding populations in neighborly Federal Republic of Germany, Austria, Central and South Bohemia. There were no significant differences founded in the genetic profile of this population to the surrounding populations.
45

Forenzní analýza biologických stop a její využití ve výuce na SŠ / Forensic Analysis of Biological Traces and its Use in High-school Education

Hrubá, Barbora January 2016 (has links)
This master thesis deals with forensic genetics. Primarily is forensic genetics put into the historical context. Then, there is described a biological material and the possibility of detecting biological traces. Further work is focused on the analysis of DNA, while there are elaborated in detail the techniques used as nucleic acid isolation, quantification of DNA, as well as types of polymerase chain reaction (PCR). Also the thesis deals with methods of obtaining DNA profiles - electrophoresis and sequencing and their variants. Finally, the thesis concern the issues of interpretation of forensic genetic data. Forensic biological exercises for high school students are processed in the didactic part. It has been tested in practice in biological seminars at Jiráskovo gymnázium in Náchod. Key words Forensic genetics, biological traces, didactics of biology
46

Forenzní analýza biologických stop a její využití ve výuce na SŠ / Forensic Analysis of Biological Traces and its Use in High-school Education

Hrubá, Barbora January 2017 (has links)
This master thesis deals with forensic genetics. Primarily is forensic genetics put into the historical context. Then, there is described a biological material and the possibility of detecting biological traces. Further work is focused on the analysis of DNA, while there are elaborated in detail the techniques used as nucleic acid isolation, quantification of DNA, as well as types of polymerase chain reaction (PCR). Also the thesis deals with methods of obtaining DNA profiles - electrophoresis and sequencing and their variants. Finally, the thesis concern the issues of interpretation of forensic genetic data. Forensic biological exercises for high school students are processed in the didactic part. It has been tested in practice in biological seminars at Jiráskovo gymnázium in Náchod. Key words Forensic genetics, biological traces, didactics of biology
47

Genetická struktura mediteránních populací kaloně Rousettus aegyptiacus / Genetická struktura mediteránních populací kaloně Rousettus aegyptiacus

Marešová, Tereza January 2012 (has links)
5 Abstract The genus Rousettus represents the only fruit bat genus distributed both in Asia and Africa reaching northern distributional limits of the Pteropodidae family. This unusual distribution pattern is related to the ability of echolocation, subsequent cave dwelling and probably other thermoregulatory and behavioural adaptations to relatively cold and dry climate. Methods for identification of genetically discrete populations were used in the presented study to acquire better comprehension of historical ways of colonization along with current dispersal and migratory patterns of the Egyptian fruit bat (Rousettus aegyptiacus) in the Mediterranean basin and adjacent range patches. Modern approaches to population and landscape genetics were applied on a dataset comprising 553 individuals from 72 localities using 20 nuclear microsatellites. Our results revealed a significant genetic distance of East African individuals and certain substructure in the northern part of the range. Cypriot population is clearly separated, and - for higher K - the isolation of colonies from Egyptian oases is highly supported. Genetic proximity of south Arabian and Sinai populations contradict current taxonomy of the species. Our findings highlight the role of seas and deserts as barriers restricting gene flow and the evolution...
48

Populační struktura afrických populací hodnocená pomocí Alu inzercí. / Population Structure of African Populations Inferred from Alu Insertions.

Fajkošová, Zuzana January 2012 (has links)
The population genetic study was carried out on 188 unrelated individuals from 5 populations of the Sahel. Relationships of nomadic Fulani to sedentary populations of different linguistic backgrounds and geographic origins were inferred from 16 polymorphic Alu insertions. Bayesian clustering approaches could be applied due to biallelic multilocus nature of the data. Fulani were shown to be divergent from neighbouring sedentary populations (Kassena and Mossi) and similar to Somali of East Africa. In context of already published genetic data, these results could be interpreted as Saharan origin of Fulani diaspora that was caused by Sahara drying out around 6 000 BP. After this initial migration of nomads to West Africa, a primarily female gene flow (integration of females) must have influenced the Fulani population. In contrast to Fulani, Songhai have shown a signal of recent admixture in concordance with historical and linguistic assumptions. KEY WORDS Alu insertions, Fulani, population genetics, Sahel
49

Pojetí vědy ve vybraných románech Simona Mawera / Conception of Science in the Selected Works by Simon Mawer

Miháliková, Veronika January 2016 (has links)
The aim of this thesis is to explore Simon Mawer's approach to science and to compare the roles of science in his novels Mendel's Dwarf and The Girl Who Fell from the Sky. The description of author's life and its influence on his work with emphasis on the scientific aspects is provided and his opinion on the relationship between science and literature given. The difference between fiction with aspects of science and science fiction is explained and other authors who deal with science in their fiction are exemplified. As Mendel's Dwarf employs genetics and eugenics and The Girl Who Fell from the Sky nuclear physics, the brief development of these scientific fields is described.
50

Factors influencing butterfly diversity of the species-rich Submediterranean region

BARTOŇOVÁ, Alena January 2019 (has links)
This thesis focuses on the history, current state, and conservation of butterfly diversity in the Submediterranean grasslands and Palaearctic steppes. The thesis is introduced with the summary of Cenozoic history of the steppe biome in Eurasia. Then it consists of three studies. The first study describes butterfly communities and microhabitat selection of a steppe specialist butterfly Proterebia afra in two relic grassland areas in the Balkans. Based on genetic markers and samples covering the whole distribution ranges, the second and third studies assess the phylogeography of two steppe butterflies, P. afra and Pseudophilotes bavius, distributed in the Irano-Anatolian region, the Balkans, as well as the northern Palaearctic steppes.

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