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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.
1

Revize taxonomie loskutáků rodu Gracula v oblasti Sumatry a přilehlých ostrovů. / Taxonomic revision of the genus Gracula in the Island of Sumatra and the southwest located islands

Švejcarová, Tereza January 2017 (has links)
Hill Mynas Gracula have a wide distribution range covering all of Southeast Asia. They became a popular cage bird due to their ability to mimic human speech. Massive demand had a tragic impact on the wild populations of Hill Mynas throughout their range. Since the first description of the species there have been significant discrepancies in the classification. Continuous pressure on the wild populations caused an urgent need of conservation attention in many places, which was hindered by taxonomical uncertainties. Decades of specialists disagreements caused crossbreeding of mynas from different areas and thus disappearance of their typical characteristics. The only possible way for taxonomic revision has become a field research. This research was focused on the taxonomic revision of the Common Hill Myna Gracula religiosa in Sumatra and its nearby islands, where the highest diversity of the genus taxa occurs. The aim was to evaluate the current situation of the wild populations and to collect the largest possible set of morphometric information. The analyses uncovered that studied taxa are all clearly distinguishable. Taxon miotera from the island of Simeulue, oftenly overlooked in literature, showed the largest differences as well as taxon robusta from Nias. If taxon robusta is recognised a full species, miotera should be upgraded to a species level as well. Mynas from the additional two locations show differences too and are both clearly distinguishable from the others. The differences dont show such significance to treat these taxa as species without further combination of morphometry and genetics. A surviving population of the Nias Hill Myna Gracula (r.) robusta, last recorded by scientists in 1939 was found during this research as well as acoustic evidence of taxon miotera from Simeulue which was also identified as possibly extinct.
2

Vývoj patra u pacientů s orofaciálními rozštěpy po primární sutuře rtu / Development of maxilla in patients with orofacial clefts after the primary cheiloplasty.

Hoffmannová, Eva January 2013 (has links)
The present study is concerned with development of maxilla, or moreprecisely palate,in course of first year of life in patients with unilateral cleft lip and palate (UCLP), before and after cheiloplasty. The metodology has it's center in processing of dental plaster casts of UCLP patients via classical and geometric morphometry. All the patients have been operated following same protocol in the neonatal period. The operation was conducted by the same surgeon Jiří Borský, M.D. in the teaching hospital Motol in Prague. In the trackedThe results suggest that the variability of shape was larger in cUCLP patients than in UCLP+M patients. Statistically significant differences in the palate shape were observed in both age categories within both defect categories. The variability of form (size and shape) was followed within each defect category and statistically significant differences between both age category was proven. In the light of average changes intha palate morphology, we tracked both anterior and posterior growth of both segments with increasing age in both defect categories. More distinctive aproximation of both segments, due to the pressure after the cheiloplasty and growth of both segments, was observed in cUCLP patients. Essencial influence of increasing gravity of the defect on changes...
3

Vývoj oronasální oblasti u dětí ve věku od 7 do 17 let: longitudinální studie / Development of the oronasal facial region in children aged 7-17 years: longitudinal study

Jungvirtová, Tereza January 2019 (has links)
This thesis is based on longitudinal monitoring of developmental changes of the oronasal region in a group of children from 7 to 17 years. Growth and shape changes, variability and sex dimorphism were monitored using 492 3D facial models of 40 boys and 47 girls. These models were obtained by yearly scanning children aged 7 to 12 years and 12 to 17 years. The Vectra 3D optical scanner was used to obtain the models and data were evaluated using classical and geometric morphometry methods (T-test, DCA, Per vertex T-test and Principal component analysis). The results of the analyses were visualized using superprojection color maps of average faces and significance maps that show statistically significant regions of oronasal region changes. During the period under review, the growth of the oronasal region is evident in both girls and boys. The most intense growth occurred in the area of the nasal spine in both sexes, so there was a lengthening of the nose. Overall, the oronasal region extended and expanded to acquire a more convex shape. Growth intensity increased in girls from 10 years and in boys from 11 years. Sexual dimorphism was pronounced up to 11 years, between 12 and 13 the differences were not as pronounced as in the previous age categories, and these changes began to increase again from 14...
4

Dimension Reduction Techniques in Morhpometrics / Dimension Reduction Techniques in Morhpometrics

Kratochvíl, Jakub January 2011 (has links)
This thesis centers around dimensionality reduction and its usage on landmark-type data which are often used in anthropology and morphometrics. In particular we focus on non-linear dimensionality reduction methods - locally linear embedding and multidimensional scaling. We introduce a new approach to dimensionality reduction called multipass dimensionality reduction and show that improves the quality of classification as well as requiring less dimensions for successful classification than the traditional singlepass methods.
5

Vývoj vybraných fluviálních jezer v nivě Lužnice / Development of fluvial lakes in the Lužnice River floodplain

Hastíková, Petra January 2012 (has links)
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.
6

Individuální růst a variabilita časných preimaginálních stádií vodní ploštice bodule obecné (Ilyocoris cimicoides) (Heteroptera: Nepomorpha: Naucoridae) / Individual growth and variability of early development stage of creeping water bug Ilyocoris cimicoides (Heteroptera: Nepomorpha:Naucoridae)

PILAŘOVÁ, Simona January 2014 (has links)
This thesis investigates an influence of environmental variables (temperature and food availability) on development and growth of the first three nymphal stages of Ilyocoris cimicoides Linnaeus, 1758 Individuals were housed individually in experimental cages from eklosis into adulthood. Experiments were carried out in a combination of four different temperatures (17 ?, 19 ?, 22 ? and 25 ? C) and two different modes of food availability (full-fed every day, red-fed every other day) (in eight treatments). The temperature significantly influenced the length of nymphal development. According to our expectation, shortest development was achieved in individuals reared at 25° C. Development period was prolonged by decreasing temperatures. Unpredictably, the nymphs of the 3rd instar had longest development at the lowest temperatures (17 ? C) whereas nymphal development of the 1st and 2nd instars ran faster Both, the lowest- (17 ? C) as well as the highest used temperature (25 ? C) are probably very close to the temperature limits, that corresponds to the limits of postembryonic development. The optimum temperature for development was 22 ? C. Furthermore, it has been found that food availability should also significantly affect growth and development. Surprisingly, less mortality was observed in individuals reared in reduced feeding treatment, except the only case - nymphs reared in low temperature (19 ? C), where higher mortality was found in individuals reared at the same food availability.
7

Morfometrická analýza dvou druhů Ameiurus melas a Ameiurus nebulosus, (Teleostei:Ictaluridae) vyskytujících se na území České republiky / Morphometric analysis of two species Ameiurus melas and Ameiurus nebulosus, (Teleostei: Ictaluridae) occurred on territory of Czech republic

PÍCHA, Roman January 2010 (has links)
North American freshwater catfishes (Ictaluridae) is family of freshwater catfishes and includes 7 genera and 48 species. Original habitat of those family is Northern and Central America, but some species were to be introduced to the other regions inclusive Europe. In Czech Republic was recorded occurrence of two species of genus Ameiurus. Brown bullhead (Ameiurus nebulosus) imported by J. Šusta in 1890, and black bullhead (Ameiurus melas), which was imported in 2003 as an admixture to load of Common carp stocking material from Croatia. Distribution of these species is restricted on a small areas in the Elbe river basin and Třeboň pond system in Southern Bohemia. These species are very similar and their resolution is possible only on the basis morphometrics and anatomical diversity (number of fin rays, serration of spine on pectoral fin). Therefore was necessary carry out detailed measuring of both species with the aim of find out appropriate next differences. We measured 63 measurements by digital slide gauge and next we quantified number of fin rays. Totaly was processed 90 black bullheads and 52 brown bullheads.
8

Původ a biologická afinita údajné gravettienské mandibuly Předmostí 30 ze sbírek Moravského zemského muzea. / Origin and Biological Affinity of the Alleged Gravettian Mandible Předmostí 30.

Drahošová, Michala January 2015 (has links)
Dissertation solves the problem of the origin of the mandible from collection of Moravian Museum in Brno. Publications of authors working in the location Předmostí u Přerova since the year 1884 have been used to achieve this goal. Simultaneously records in the incremental books of MZM in Brno have been researched, unfortunately without success. Therefore research of the biological affinity of the mandible P30 with others gravettiens discovery has been accepted as well as variability of recent humans. For study we used methods of geometric morphometrics, which allows us better clarify shape discrepancies in comparison with standard analytic methods. Comparison of shape variability of the mandible we used 91 cranial CT exposures of the recent Czech population. We placed 42 landmarks to segmented 3D models of the mandible and we made a PCA analysis. To extend the argument for justifiability to incorporate studied sample among discoveries from Předmostí u Přerova we created file of linear proportions of the tooth crown based on available publications and our own measuring. Morphological study, shape analysis of the mandible and dimension of the teeth leads us to results that the mandible P30 in our study can really belong to the Gravettien Age. Key words: Mandible, Molars, Předmostí u Přerova,...
9

Variabilita křídelní žilnatiny vážek (Insecta: Odonata) - geometricko-morfometrická studie / Variation in dragonfly wing venation with application of geometric morphometrics (Insecta: Odonata)

Přibylová, Petra January 2015 (has links)
The pattern of wing venation in dragonflies (Odonata) bears a set of characters commonly used in systematics. The aim of this thesis is to identify the wing venation variability of dragonflies by various methods of geometric morphometric. The wing venation variability was examined on the level of suborder, family, species and also in respect to dimorphism through the principal component analysis (PCA), redundancy analysis (RDA) and centroid size. Data set consisting of images of 46 dragonfly species, belonging to 43 genera and 24 families was obtained from institutional entomological collections. The research carried out that Zygoptera have a large variety of wing contours. The wing venation variability of Epiprocta is shown primarily in the costa and node area. Between sexes there is no noticeable difference in shape or structure of the wing. The ratio between wing length and width and the pterostigma shape is dependent on dragonfly body size. Key words: Odonatoptera, Odonata, Epiprocta, Zygoptera, wing venation, variability, geometric morphometrics
10

Ontogeneze vybraných taxonů trilobitů a agnostoidů ze středního kambria barrandienské oblasti / Ontogeny of selected taxa of middle Cambrian trilobites and agnostoids of the Barrandian area

Laibl, Lukáš January 2017 (has links)
This thesis deals with the ontogeny of trilobites and agnostids from the Cambrian of the Skryje-Týřovice and Příbram-Jince basins (Barrandian area, Bohemian Massif). Thesis is presented as a compilation of four papers that were published in scientific peer-reviewed journals. The introduction of the thesis serves as a general overview of the trilobite post- embryonic development and connects all published papers together. All four papers presented here are focussed on modern description of the post-embryonic development of Sao hirsuta, Ptychopariida sp. A, Ptychopariida sp. B, Ptychopariida sp. C, Ellipsocephalus hoffi, Ellipsocephalus polytomus, Hydrocephalus carens and Ecca- paradoxides pusillus. In addition, a discussion about the life-history strategies of early developmental trilobite stages is presented. It has been suggested that Sao hirsuta and Ptychopariida sp. A had benthic protaspides and that the early ontogenetic stages of Ptychopariida sp. B, Eccaparadoxides pusillus and Hydrocephalus carens were likely lecithortophic. Consequently, it has been documented that species with benthic protaspides show a strongly restricted geographic distribution and that lecithotrophic taxa seem to be associated with higher latitude areas. The developmental patterns of Ellipsocephalus hoffi and...

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