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Differentiation in the polyploid complex Libanotis pyrenaica (Apiaceae)
Přívozníková, Hana ; Chrtek, Jindřich (advisor) ; Vít, Petr (referee)
Polyploidization belong to principal evolutionary mechanisms in plants. Although it is rather rare in the family Apiaceae, there are several interesting polyploid complexes here. The present study deals with Libanotis pyrenaica, species three previously reported ploidy levels, namely diploid (2n = 2x = 22), tetraploid (2n = 4 x = 44) and most likely very rare triploid (2n = 3x = 33). The present study aims at geographical pattern of ploidal diversity in central Europe, genetic variation and selected biological features of this species. Flow cytometru, analysis of two chloroplast DNA markers (trnF-trnL and cp018-cp020), morphometrics and in vitro germination experiments were used. The tetraploid cytotype occurs throughout the studied area; in the Czech Republic it was found in the České středohoří Mts., southern Bohemia and Moravia, in Slovakia it especially in the Carpathian mountains in western and central parts of the country and in the Pieniny Mts. in the northeast. Tetraploid cytotype occurs mainly in central-east Europe; in the Czech Republic it is common in the lowlands along the river of Labe and locally in Moravia; in Slovakia it was found along the river of Váh, in the Slovenské rudohorie Mts. and in the Belanské Tatry Mts. A mixed-ploidy population (2x, 4x) was discovered in southern...
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Development of fluvial lakes in the Lužnice River floodplain
Hastíková, Petra ; Šobr, Miroslav (advisor) ; Havlíková, Petra (referee)
The object of the thesis is to evaluate the development of several chosen fluvial lakes in the basin of the river Lužnice, mainly in the section between the border with Austria and Suchdol nad Lužnicí. The river Lužnice in this particular section represents low intensity of modification. Many fluvial lakes are situated there and the river is meandering remarkably in the area. The first part of the thesis deals with the characteristics of the natural conditions in the basin of Lužnice and the defined floodplain and the problematics of lakes and their determination. The main part of the thesis focuses on the evaluation of the flow development and fluvial lakes of the Lužnice floodplain based on the data of a aerosnapshoting. Because of the gradual decease of the meanders and straightening of the flows, it is possible to claim that the river has been considerably shortened with the passing time. In the thesis, 34 chosen fluvial lakes, that were measured morphometrically and batymetrically, were studied in detail.
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The morphology of avalanche paths
Krause, David ; Křížek, Marek (advisor) ; Treml, Václav (referee)
An avalanche path is a landform, that is being modeled by surface snow avalanches, debris flows and other slope processes. It consists of starting zone, track and runout zone. The submitted bachelor thesis is concerned with the characteristics of avalanche paths used in literature and generates their classification. The morphometric GIS analysis is performed in the Eastern High Sudetes. The measured vlaues of 16 avalanche paths from 6 sites are statistically processed and compared. The Sudetic paths are shorter but they have similar slope in comparison with paths in alpine environment. The spatial distribution of avalanche paths is bound to lee parts of the anemo-orographic systems. The aspect is predominantly southeastern, the slope is between 20 and 30ř and the length is usually between 200 and 400 m. The path lenght depends inversely on the slope of the starting zone. There is also a relation between the avalanche path morphology and the area of alpine tundra on the etchplain above the timberline, from where the snow is being blowed to the starting zones. Key words: snow avalanche, morphometry, Eastern High Sudetes, Altvatergebirge, Glatzer Schneeberg
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Phylogeography and population structure of two loach species (Teleostei: Nemacheilidae) in Southeast Asia
Dvořák, Tomáš ; Bohlen, Jörg (advisor) ; Říčan, Oldřich (referee)
The freshwater fish species Schistura robertsi and Paracanthocobitis zonalternans belong to the family Nemacheilidae, which is distributed across whole Eurasia and with one species in northeast Africa. P. zonalternans occurs in lowland habitats through western Southeast Asia from Central Myanmar until northern Malaysia. The distribution area is of biogeographic interest, because it crosses several known biogeographic barriers, namely the border between Indian and Indochinese freshwater fauna along the Salween River, the Isthmus of Kra, the Krabi - Surat Thani line and the Kangar - Pattani line. In the present study, around 250 specimens of P. zonalternans from 62 localities across the whole distribution area were investigated using genetic (nuclear and mitochondrial sequences), morphologic and geologic data. The genetic data reveal the existence of seven major clades within the analysed material, each of them with a distinct geographic distribution area and only few cases of overlap, but with occurrence of some cases of secondary contact. Divergence time estimations suggested that P. zonalternans is about 18 my old, and a biogeographic analysis located the region of origin in the Tenasserim region (nowadays southern Myanmar). The global sea level fluctuations seem to have had a strong impact on the...
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Population structure, migration and dynamics in Africa and Arabia
Čížková, Martina ; Černý, Viktor (advisor) ; Frynta, Daniel (referee) ; Zrzavý, Jan (referee)
In addition to the interaction of evolutionary forces, the population history of the African Sahel and Arabia has been influenced by the spread of Neolithic cultural innovations. The reflection of these processes today is a very complex structured diversity of the current populations, which is presented here through the analysis of several genetic markers. The aim is to provide a comprehensive view of the history of demographic processes in the Sahel and Arabia, by combining genetic, linguistic, subsistence and geographical data obtained from local populations. A study of a large dataset of mtDNA sequences showed that Arabia was a major crossroads in gene flow, and although it was colonized by anatomically modern humans from East Africa, today's differentiation from Africa is greater than the differentiation between local populations in these regions. Even the Sahel was an important biocorridor in the past. Today, we encounter populations of various subsistence strategies (nomadic pastoralists and settled farmers), between which gene flow has been severely restricted. A comparison of uniparently inherited loci in both groups points to different migratory activity in the eastern and western parts of the Sahel. Analyzes of Alu elements, which indicated the inclination of West African herders (Fulbs)...
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Experimental model of the ventral spinal cord lesion in rats.
Štěpánková, Kateřina ; Machová Urdzíková, Lucia (advisor) ; Martončíková, Marcela (referee)
A spinal cord injury (SCI) is a damage to the spinal cord that causes permanent or temporary changes in motor and sensory functions. In humans, the traumatic impact to spinal cord is mostly directed from the ventral part of the spinal column, even though SCI models are principally directed from the dorsal part of the spinal column due to easier surgery. The aim of the work described in this thesis was to develop clinically more relevant, easily reproducible and relatively inexpensive model of the ventral spinal cord lesion in rats which replicates SCI in humans as closely as possible by its pathology, completeness, level and regeneration. For the surgery we used a modification of a balloon- compression technique. The balloon of the 2F embolectomy Fogarty's catheter was placed to the anterior epidural space via laminectomy at the level of T10 and when the final position of the catheter was achieved at the spinal level T8 in front of the anterior median fissure, a balloon was rapidly inflated with 10 μl or 15 μl of water for 5 minutes. Other two groups - laminectomy only and ventral placement of the catheter without inflation were used as controls. The motor functions were evaluated by the BBB test and ladder walking test. In BBB test we observed significantly impaired motor functions in the 15 μl...
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Structural Patterns of Cognitive Deficits in MR Imaging.
Buksakowska, Irena ; Hořínek, Daniel (advisor) ; Rulseh, Aaron (referee) ; Dušek, Petr (referee)
Structural and diffusion imaging patterns that can be evaluated using MRI in patients with cognitive deficits are the central theme of the proposed work. First, the clinical and neuroimaging background of dementias has been reviewed in a broader context, with a special focus on Alzheimer's disease (AD) and differential diagnoses. The second part of this thesis contains four consecutive experimental studies. The primary objective of the first two studies was to obtain structural and microstructural information on the neurodegenerative processes characteristic for AD on global and regional levels. For this purpose, several complementary approaches were used and the focus was shifted from grey to white matter (GM/WM). The following two studies focused on the differential context of WM microstructural alterations in normal pressure hydrocephalus (NPH) and distinctive patterns of WM disintegrity in temporal lobe epilepsy (TLE). The most important conclusion of our studies is that structural and diffusion imaging proved to be useful in identifying regionally specific and disproportionate loss of brain volume and microstructure in several pathological processes underlying cognitive deterioration. The use of distinctive morphometric methods yielded complementary information on AD-related atrophy patterns,...
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The analysis of geomorphological pronunciation of neotectonics on Cordillera Blanca faults
Burkytová, Šárka ; Vilímek, Vít (advisor) ; Klimeš, Jan (referee)
The study deals with analysis of of geomorphological pronunciation of neotectonics along the based on fault slope in the South American Cordillera Blanca range. It contains research about physical-geographycal characteristic of the mountain range with the focus on geology, geomorphology and the theoretical concept of forms on fault slopes and neotectonic acitivity. In the practical part of the thesis, the selected area of the mountain range was mapped using Google Earth imagery. On the base of created map the forms associated with the active tectonic uplift of the Cordillera Blanca were analyzed and invented. Then the longitudinal profiles of rivers that flow across the fault zone were created and analyzed from the digital terrain model. The block structure of the mountain range was analyzed too. Keywords Cordillera Blanca, geomorphology, morphometry, neotectonics, Peru
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Biologická a molekulární charakteristika Cryptosporidium suis-like
VLNATÁ, Gabriela
Cryptosporidium parvum VF383, more commonly known as Cryptosporidium suis-like, has been reported in humans, domesticated ruminants, and wild rats worldwide and described under several names including Cryptosporidium suis-like, based on its close phylogenetic relationship to C. suis. Unlike C. suis, however, it has never been detected in pigs. In the present work, Cryptosporidium suis-like originating from wild brown rats was not infectious for piglets or calves but was infectious for laboratory brown rats, BALB/c mice, and Mongolian gerbils. The prepatent period was 4-5 days for all rodents. The patent period was longer for rats (>30 days) than other rodents (<20 days). None of the rodents developed clinical signs of infection. In all rodents, life cycle stages were detected in the colon by histology and electron microscopy. Oocysts were morphometrically similar to those of C. parvum and smaller than those of C. suis, measuring 5.20 × 4.94 m. Phylogenetic analyses of SSU, actin, and HSP70 gene sequences revealed Cryptosporidium suis-like to be genetically distinct from, C. suis, and other described species of Cryptosporidium. Morphological, genetic, and biological data support the establishment of Cryptosporidium suis-like as a new species, and we propose the name Cryptosporidium occultus sp. n.
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Phylogeography and population structure of two loach species (Teleostei: Nemacheilidae) in Southeast Asia
Dvořák, Tomáš ; Bohlen, Jörg (advisor) ; Říčan, Oldřich (referee)
The freshwater fish species Schistura robertsi and Paracanthocobitis zonalternans belong to the family Nemacheilidae, which is distributed across whole Eurasia and with one species in northeast Africa. P. zonalternans occurs in lowland habitats through western Southeast Asia from Central Myanmar until northern Malaysia. The distribution area is of biogeographic interest, because it crosses several known biogeographic barriers, namely the border between Indian and Indochinese freshwater fauna along the Salween River, the Isthmus of Kra, the Krabi - Surat Thani line and the Kangar - Pattani line. In the present study, around 250 specimens of P. zonalternans from 62 localities across the whole distribution area were investigated using genetic (nuclear and mitochondrial sequences), morphologic and geologic data. The genetic data reveal the existence of seven major clades within the analysed material, each of them with a distinct geographic distribution area and only few cases of overlap, but with occurrence of some cases of secondary contact. Divergence time estimations suggested that P. zonalternans is about 18 my old, and a biogeographic analysis located the region of origin in the Tenasserim region (nowadays southern Myanmar). The global sea level fluctuations seem to have had a strong impact on the...
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