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Evolutionary and developmental aspects of dentition of squamate reptiles
Zahradníček, Oldřich ; Horáček, Ivan (advisor) ; Míšek, Ivan (referee) ; Peterková, Renata (referee)
EVOLUTIONARY AND DEVELOPMENTAL ASPECTS OF DENTITION OF SQUAMATE REPTILES Summary of the PhD. thesis Dentition and its evolutionary modifications played important roles during the radiation of reptiles. It is generally accepted that a plesiomorphic state for reptiles is represented by homodont, polyphyodont dentition with conical or cylindroconical teeth. However, in contrast to mammalian dentition which is the object of intensive research, reptilian dentition is studied only rarely. I therefore focused on developmental and evolutionary aspects of squamate dentition and used histological, immunohistochemical and in situ hybridization methods, computerised tomography, rentgenography and scanning electron microskopy. The goals of this work were as following: (a) to choose the model taxa representing squamate lineages relevant from a phylogenetic position as well as possessing dissimilar types of dental adaptations; (b) to evaluate using of these taxa as model species; (c) in these taxa describe basic odontogenic features. As a species with generalized dentition gecko Paroedura picta was chosen, the up coming reptilian model species with features also present in a wide spectrum of other lizards. I focused mainly on the developmental differences between teeth of the null and functional generations, development...
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The key to determining the boid snakes of the subfamily Erycinae for the needs of the ČIŽP.
ŽÍDEK, Jakub
Snakes of the subfamily Erycinae belong to family Boidae. Erycinae are spread to the North America, North Africa and Asia. Due to their attractive appearance and small size are interesting business article. Every species of this subfamily is subject of CITES agreement. This work contains collected data from imports of subfamily Erycinae to the Czech Republic and EU and contains data from trade websites ifauna.cz and terraristik.com. Finally comprehensive key was made for all 15 species of subfamily Erycinae which was verified by inexpert public and all deficits were corrected.
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Key to boiinae snakes for The Czech Environmental Inspectorate.
VÖRÖS, Jan
Species of Boinae are of a great interest among breeders, wheter it?s due to their size, attractive colour patters or the way they hunt their prey. However, some species are endemic, threatened by the habitat loss or other causes and therefore they are subject to the CITES or they are placed on the IUCN Red List. In the last 20 years there have been numerous changes in the taxonomy of all families. New species were discovered, many were also lifted from the level of subspecies to the species level. This work focuses on 34 species of the subfamily Boinae, summarizes the hitherto published data and determination characters. It also contains data collected from web advertising sites iFauna and Terraristik, which is used to form images of the species traded in the Czech Reublic respectively neighboring Germany. Finaly the work includes a comprehensive key to all 34 snakes species complemented by illustrations.
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Active contour models in medical image segmentation
Nagy, Ivan ; Szabó, Z.
Active contour models are very suitable to image segmentation. A contour is a set of point which has an energy function. This energy function comes from both internal and external sources. This paper includes internal and external energy definition and a Matlab implementation of active contours.
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