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Forks for handling logs
Seďa, Marek ; Juřík, Josef (referee) ; Škopán, Miroslav (advisor)
This master’s thesis with product design forks for handling logs as attachments for tractors Zetor Forterra the specified load capacity 1200 kg. The work is mainly focused on the design frame and fork clamps, the necessary calculations and ultimately strength check of designed structures. The work is also addressed in detail the linear hydraulic motor used for the rotational movement of the jaws, including the calculation of fork. Then there are the design calculations and stress analysis of journals. It also checked the stability of the machine. Stress analysis is performed for different load conditions and the jaw frame finite elements. As another part is making all the drawings.
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Morfogeneze orálního skeletu mihule ve vztahu k evoluci čelistí
Romášek, Marek ; Černý, Robert (advisor) ; Jandzík, Dávid (referee)
4 Neural crest-derived cellular cartilage is one of the defining characteristics of vertebrates. Elaboration of this tissue and its patterning allowed the evolution of jaws in the gnathostome lineage. Together these hallmarks helped jawed vertebrates become one of the dominant taxons in the animal kingdom. Lampreys, as basal jawless vertebrates, lie at a unique phylogenetic position that makes them ideal organisms for the study of evolution of vertebrate/gnathostome novelties. Larval lampreys possess a special oral skeleton composed of a tissue related to cartilage, termed mucocartilage. Despite considerable attention that has been paid to the evolutionary significance of mucocartilage, it is not yet clear, how this unique feature arises in development and to what extent it is homologous to gnathostome jaws. In this study, the development of oro-pharyngeal region was analyzed in the sea lamprey Petromyzon marinus. SEM imaging revealed shaping and topographic relationships of embryonic tissues, detailed plastic histology coupled with expression analyses of several molecular markers were used to describe origin, histogenesis and morphogenesis of mucocartilage. Furthermore, genetic regulation of the tissue was investigated in order to identify its unique or shared features. Mucocartilage is seen to...
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Cephalopod jaws from the Bohemian Cretaceous Basin - taxonomy and stratigraphic implications
Kozlová, Zuzana ; Košťák, Martin (advisor) ; Vašíček, Zdeněk (referee)
This work is focused on systematic research of cephalopod jaws from the Late Cretaceous. Samples of 147 newly recorded nautiloid rhyncholites from the Bohemian Cretacoeus Basin and one new ammonite rhyncholite from Řepov village were systematically analyzed. The new collection of lower ammonite jaws (aptychi) consists of 32 specimens. Nautiloid rhyncholites from localities Turkaňk, Úpohlavy, and Dreisen were determined as Nautilorhynchus simplex. Conchorhynchs from locality Vinary u Vysokého Mýta belong to the species Conchorhynchus cretaceous, which is associated with the commonmost species Eutrephoceras sublaevigatum. Ammonite rhyncholite is left in the open nomenclature due to its uncertain systematic position and it is not assigned to any ammonite species. Records of aptychi from the locality of Úpohlavy and Pecínov represent mainly species of heteromorphic ammonites - baculitids (Baculites, Sciponoceras). The total diversity of species from both localities reaches 20 ammonite species. The two jaw morphotypes (2 species of aptychi) are reported from the Bohemian Cretaceous Basin for the first time herein. Of the high importance, it is a record of ammonite Prionocyclus germari from Úpohlavy with associated lower jaws in situ within the body chamber. Aptychus of this taxon has never been...
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Morfogeneze orálního skeletu mihule ve vztahu k evoluci čelistí
Romášek, Marek ; Černý, Robert (advisor) ; Jandzík, Dávid (referee)
4 Neural crest-derived cellular cartilage is one of the defining characteristics of vertebrates. Elaboration of this tissue and its patterning allowed the evolution of jaws in the gnathostome lineage. Together these hallmarks helped jawed vertebrates become one of the dominant taxons in the animal kingdom. Lampreys, as basal jawless vertebrates, lie at a unique phylogenetic position that makes them ideal organisms for the study of evolution of vertebrate/gnathostome novelties. Larval lampreys possess a special oral skeleton composed of a tissue related to cartilage, termed mucocartilage. Despite considerable attention that has been paid to the evolutionary significance of mucocartilage, it is not yet clear, how this unique feature arises in development and to what extent it is homologous to gnathostome jaws. In this study, the development of oro-pharyngeal region was analyzed in the sea lamprey Petromyzon marinus. SEM imaging revealed shaping and topographic relationships of embryonic tissues, detailed plastic histology coupled with expression analyses of several molecular markers were used to describe origin, histogenesis and morphogenesis of mucocartilage. Furthermore, genetic regulation of the tissue was investigated in order to identify its unique or shared features. Mucocartilage is seen to...
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Forks for handling logs
Seďa, Marek ; Juřík, Josef (referee) ; Škopán, Miroslav (advisor)
This master’s thesis with product design forks for handling logs as attachments for tractors Zetor Forterra the specified load capacity 1200 kg. The work is mainly focused on the design frame and fork clamps, the necessary calculations and ultimately strength check of designed structures. The work is also addressed in detail the linear hydraulic motor used for the rotational movement of the jaws, including the calculation of fork. Then there are the design calculations and stress analysis of journals. It also checked the stability of the machine. Stress analysis is performed for different load conditions and the jaw frame finite elements. As another part is making all the drawings.
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Branchiobdellidan population on alien species of crayfish in the Czech Republic
LOŽEK, Filip
The thesis summarizes the current knowledge about the class Branchiobdellae including their anatomy, ecology and geographic distribution with respect to the presence of introduced species in Europe. Using samples of Branchiobdellidan obtained from two introduced species of crayfish caught in a pond near Čáslavice u Moravských Budějovic (signal crayfish, Pacifastacus leniusculus) and in Černíský stream (eastern crayfish, Orconectes limosus), two out of seven European species of Branchiobdellidan were identified, namely B. parasita with 100% presence in the eastern crayfish and 58.7% presence in the signal crayfish, and B. pentodonta with 41.3% presence. Based on data collected from the caught crayfish and samples of Branchiobdellidan, the individual weight of eastern crayfish was proved to influence the quantity and biomass of Branchiobdellidan on the body of crayfish (p<0.001), i.e. increased quantity and biomass of Branchiobdellidan was found on more robust specimens of crayfish, however the effect of gender was not statistically significant. With respect to the signal crayfish, a significant difference was observed in the quantity and biomass of Branchiobdellidan depending on the weight of the crayfish (p<0.001), and the influence of the gender of the crayfish was detected (p<0.001), i.e. the quantity and biomass of Branchiobdellidan was higher on the surface of male specimens of crayfish. The presence of eggs in some female signal crayfish had no significant effect on the quantity and biomass of Branchiobdellidan (p=0.052), however in combination with the weight, the influence of the presence or absence of eggs was proved (p=0.011), more robust females showed increased quantity and biomass of Branchiobdellidan.
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