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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

Landmark Analysis of Musteloid Carnassials Applied to Taxonomic Identification and Examination of Sexual Dimorphism and Regional Morphotypes

Christine, Joel Alvin 15 August 2012 (has links)
Guy Wilson Cave (GWC) in Sullivan County, Tennessee holds many late Pleistocene mammal fossils. Based on visual morphology, several partial mandibles with lower carnassial from GWC appeared to be musteloids. Geometric morphometrics has been successfully used to identify fragmentary fossils, so a landmark based, 2 dimensional technique was applied to identify the GWC musteloids using the lower carnassial. Digital images of several GWC fossils and of extant reference musteloids were combined using morphometric programs tpsDIG1, tpsUtil, and tpsSuper. Statistical data analysis was performed in PASW Statistics. Results successfully separated Mephitis mephitis (striped skunk) from M. macroura (hooded skunk) and Martes americana (American marten) from M. pennanti (fisher). Sex-based and geographical patterns were also found in the data. Sex separated all three species via the lower carnassial. Geographic divisions were found for Mephitis mephitis, Martes americana and M. pennanti populations that hint at interestingly unique biogeographical histories for each taxon.
2

Shape Change and Variation in the Cranial Morphology of Wild Canids (Canis lupus, Canis latrans, Canis rufus) Compared to Domestic Dogs (Canis familiaris) Using Geometric Morphometrics

Schmitt, E., Wallace, S. 01 January 2014 (has links)
Wild canid populations exhibit different anatomical morphologies compared to domesticated dogs in North America. This is particularly important concerning archaeological sites, which may contain early domesticated species, for the proper identification of osteological remains. Previous studies have indicated domestic dogs exhibit a shorter rostrum accompanied by a crowded tooth row; however, none describe the overall complexity of these changes. Consequently, using a landmark-based geometric morphometric analysis, cranial morphological characteristics were examined in North American wild canids: the gray wolf (Canis lupus), coyote (Canis latrans), red wolf (Canis rufus), and the domestic dog (Canis familiaris). The shape and size of the cranium in lateral and ventral views were compared between the three wild species to the group of domesticated dogs. Wild canids clustered separately from the domestic group in all statistical analyses. Results indicate an expansion of the orbital region, a compression of the rostrum, and an overall warping in the shape and orientation of the skull. In domestic species, there is also a downward shift in the frontal portion of the skull accompanied by the braincase assuming a more upward position. This technique successfully depicted how slight changes in isolated areas of the cranium can have an impact on the overall shape and morphology of the skull. We presume these changes in cranial anatomy reflect the recent selective pressures domestic dogs have undergone since diverging from their wild ancestors.
3

Impact of local recurrence on cause-specific death after stereotactic body radiotherapy for early-stage non-small cell lung cancer: dynamic prediction using landmark model / 早期非小細胞肺癌に対する体幹部定位放射線治療後の局所再発が疾患特異死亡に及ぼす影響:ランドマークモデルによる動的予測

Ueki, Kazuhito 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第23785号 / 医博第4831号 / 新制||医||1057(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 伊達 洋至, 教授 中本 裕士, 教授 鈴木 実 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
4

Are landmarks analysis adequate to identify fish assemblages in a subtropical ecosystem? Study of case for the Araçá Bay (São Sebastião, Brazil) / Analises de pontos homólogos são adequadas para identificar assembleias de peixes em um ecossistema subtropical? Estudo de caso para a Baía do Araçá (São Sebastião, Brasil)

Siliprandi, Carolina Correia 08 August 2018 (has links)
This thesis is part of the project \"Biodiversity and functioning of a subtropical coastal ecosystem: a contribution to integrated management\" funded by FAPESP - São Paulo Research Foundation - Process 2011/50317-5. Known as Biota Araçá, this project was performed in order to evaluate the diversity and the functionality of a subtropical tidal flat located at the northern coast of São Paulo State, a high diversity area. Our study, based on landmark analysis of fish body shape and otoliths shape, was conducted at the University of São Paulo in collaboration with researchers from the Institut de Ciències del Mar (Consejo Superior de Investigaciones Cientificas, Barcelona, Spain). The thesis was organized in five chapters. In the first one, we present a historical review about the use of morphology as a tool for the Science. Initially this theme was to supply my curiosity about \"how the shape of organisms contributed to the development of biodiversity studies\". The second chapter shows the dependence of the fish assemblages\' morphological structure according to the samplers utilized. For that, nine fishing gears were used to sample the Araçá fish assemblages and we determined which samplers are more useful to represent the total fish morphological variability of the area. Given the heterogeneity and complexity of habitats of Araçá Bay, we supposed that some habitats have major influence in the morphological diversity. Therefore, the aim of the third chapter was to determine how fish diversity techniques reveal the ichthyofauna of the three main habitats of Araçá Bay: intertidal, inner/outer sublittoral, marginal shallow sublittoral (elected as results of the previous chapter). Here we emphasize the importance of abundance data and morpho-functional approaches to understand fish habitat complexities, and consequently, the ecosystem functioning. Thus, we present the more sensible habitats in case of the Araçá\'s environmental degradation. During the development of our study, one question emerged: \"are sagittae landmarks able to describe the fish assemblage biodiversity as well as are fish body shapes?\" To answer this question, in the fourth chapter, the morphological correspondence between fish body shapes and otolith sagittae shapes were assessed. We investigated 43 species using different shape descriptors, attempting to habit, diet, swimming type, and hearing capabilities. Other specific questions were answered: 1- which method: shape indices, wavelets or landmarks, better discriminate species classification and, 2- which one shows the ecological significance of otoliths? In the last chapter, considerations are presented taking in account our initial question \"Are landmarks analysis adequate to identify fish assemblages in a subtropical ecosystem?\" The conclusion is that the method is a useful tool to describe fish body and otolith shapes as well as to define fish assemblages in highly diverse ecosystems. / Esta tese é parte do projeto \"Biodiversidade e funcionamento de um ecossistema subtropical: uma contribuição ao manejo integrado\" financiado pela FAPESP - Fundação de Amparo a Pesquisa do Estado de São Paulo - Processo 2011/ 50317-5. Conhecido como Biota Araçá, este projeto foi desenvolvido com o objetivo de avaliar a diversidade e a funcionalidade de uma planície de maré subtropical localizada no litoral norte do Estado de São Paulo, uma área de alta diversidade. Nosso estudo, baseado na análise de pontos homólogos relacionados à forma dos corpos de peixes e à forma de otólitos, foi conduzido na Universidade de São Paulo com a colaboração de pesquisadores do Institut de Ciències del Mar (Consejo Superior de Investigaciones Cientificas, Barcelona, Espanha). A tese está organizada em cinco capítulos. No primeiro, apresentamos uma revisão histórica sobre o uso da morfologia como ferramenta para a Ciência. Inicialmente, este tema surgiu a partir da nossa curiosidade sobre \"como a forma dos organismos contribuiu para o desenvolvimento dos estudos de biodiversidade\". O segundo capítulo mostra a dependência da estrutura morfológica das assembléias de peixes de acordo com os amostradores utilizados. Para isso, nove artes de pesca foram empregadas para amostrar as assembléias de peixes do Araçá e, foi analisado quais delas foram mais úteis para representar a variabilidade morfológica total das espécies presentes na área. Dada a heterogeneidade e complexidade dos habitats da Baía do Araçá, supusemos que alguns deles apresentariam maior influência na diversidade morfológica da ictiofauna. Assim, o objetivo do terceiro capítulo foi analisar como as técnicas utilizadas na avaliação da diversidade de peixes revelam esta diversidade nos três principais habitats da Baía do Araçá: entremarés, sublitoral interno/externo, sublitoral marginal raso (eleitos a partir dos resultados obtidos no capítulo anterior). Aqui, enfatizamos a importância dos dados de abundância e de abordagens morfofuncionais para entender as complexidades dos habitats para os peixes e, consequentemente, o funcionamento do ecossistema. Ainda aqui, apresentamos os habitats mais sensíveis no caso de uma degradação ambiental do Araçá. Durante o desenvolvimento do estudo, uma questão emergiu: \"pontos homólogos em sagittae são capazes de descrever a biodiversidade da assembléia de peixes, assim como o são as formas corporais?\" Para responder esta questão, no quarto capítulo, avaliamos a correspondência morfológica entre formas corporais de peixes e formas de otólitos sagittae. Nós investigamos 43 espécies utilizando diferentes descritores de forma, com vistas aos hábitos, dieta, tipo de natação e capacidades auditivas. Outras questões específicas foram respondidas: 1- qual método: índices de forma, wavelets ou landmarks, melhor discriminam as espécies para classificação e, 2- qual deles mostra a significância ecológica dos otólitos? No último capítulo, são apresentadas considerações levando em conta nossa pergunta inicial \"A análise de pontos homólogos é adequada para identificar assembléias de peixes em um ecossistema subtropical?\" A conclusão é que o método é uma ferramenta útil para descrever formas de corpos de peixes e otólitos, bem como definir associações de peixes em ecossistemas altamente diversificados.

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