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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.
11

A quantitative assessment of infraorbital morphology in Homo: testing for character independence and evolutionary significance in the human midface

Maddux, Scott David 01 January 2011 (has links)
Features of the infraorbital region, such as infraorbital surface topography, infraorbital surface orientation, and curvature of the zygomaticoalveolar crest, have long played a prominent role in phylogenetic analyses of Homo. However, there is currently considerable debate regarding the phylogenetic reliability of infraorbital characters, as numerous researchers have questioned the degree to which these features are morphologically independent of one another and facial size. These questions largely stem from methodological limitations for accurately quantifying the curvilinear morphology of the infraorbital surface and zygomaticoalveolar crest, which have significantly impeded the ability to discern patterns of infraorbital integration and allometry. In this study, infraorbital surface and zygomaticoalveolar crest morphology are precisely assessed, through geometric morphometric methodologies well-suited for quantifying complex curvilinear structures, in a large sample of fossil (n = 71) and recent Homo (n = 303). Once quantified, measures of infraorbital surface topography, infraorbital surface orientation and zygomaticoalveolar crest curvature are further evaluated for intercorrelation and allometry in order to more fully evaluate the morphological independence of commonly cited infraorbital characters. The results of this study indicate that most aspects of infraorbital surface topography, infraorbital surface orientation and zygomaticoalveolar crest curvature are significantly correlated with facial size across Homo. Moreover, certain aspects of infraorbital shape, such the degree of infraorbital surface depression and the overall curvature of the zygomaticoalveolar crest, appear to show additional, size-independent, intercorrelations, suggesting they form a singular "infraorbital complex." In light of these results, the use of infraorbital characters as separate independent characters in phylogenetic assessments of Homo is called into question, while the importance of facial size in human craniofacial evolution is further highlighted.
12

Serbentiniai amarai (Hemiptera, Sternorryncha: Pemphigidae, Aphididae) Lietuvoje / Currant aphids (hemiptera, sternorryncha: pemphigidae, aphididae) in lithuania

Bašilova, Jekaterina 08 September 2009 (has links)
Šio darbo tikslas yra tirti Lietuvos serbentinių amarų biologiją, įvairovę ir sistematiką. Lietuvoje registruota 14 serbentinių amarų rūšių (Rakauskas, Rupais, Juronis, 1992). Amarai tyrimams buvo rinkti 2003-2005 metais Vilniaus ir Kretingos rajonuose bei Kuršių nerijoje. Be to, panaudota medžiaga, saugoma Vilniaus Universiteto Zoologijos katedros kolekcijoje. 2003-2005 metais Lietuvoje buvo rasta 10 serbentinių amarų rūšių, registruotos naujos Cryptomyzus alboapicalis radimvietės mūsų šalyje, ir rastos tris Lietuvai naujos amarų rūšys: Aphis lamiorum, Cryptomyzus ulmeri ir Hyperomyzus lampsanae. Vilniaus Universiteto Zoologijos katedros kolekcijoje rasta 13 serbentinių amarų rūšių. Patikrinus kolekcinę medžiagą, pirmą kartą Lietuvoje rasti Eriosoma grossulariae rūšies amarai. Nustatytos naujos Cryptomyzus korschelti, Hyperomyzus pallidus ir Nasonovia ribisnigri radimvietės. Pirmą kartą Lietuvoje registruotas Cryptomyzus stachydis nuo Stachys silvatica ir Galeopsis sp.. Cryptomyzus galeopsidis ir Cryptomyzus maudamanti yra morfologiškai labai panašios rūšys, kartais jas sunku teisingai apibūdinti. Per tyrimų laikotarpį Cryptomyzus maudamanti rūšies amarų Lietuvoje nerasta. Kanoninės diskriminantinės funkcijos, pateiktos apibūdinimo raktuose (Guldemond 1991a; Heie 1994), negali patikimai atskirti C. galeopsidis ir C. maudamanti (17 ir 18 lentelės). Naudojant Čekijos Mokslų Akademijos Entomologijos Instituto kolekcinę medžiagą buvo atlikta diskriminantinė analizė ir gauta... [toliau žr. visą tekstą] / The aim of this study was to learn about the biology and diversity of currant aphids in Lithuania. 14 currant aphid species have been recorded in Lithuania (Rakauskas, Rupais, Juronis, 1992). For this study aphids were collected in Vilnius and Kretinga districts and on Curonian spit in 2003-2005. Currant aphid collection stored at the Department of Zoology, Vilnius University, was also analyzed. In 2003-2005 10 species of currant aphids were found in Lithuania, new collection sites of Cryptomyzus alboapicalis were detected and three new to Lithuania aphid species: Aphis lamiorum, Hyperomyzus lampsanae and Cryptomyzus ulmeri were found. 13 currant aphid species are stored at the collection of Department of Zoology, Vilnius University. Eriosoma grossularia was found after checking the collection material with a new Daniellson’s identification key to genus Eriosoma. More collection sites of Hyperomyzus pallidus, Cryptomyzus korschelti and Nasonovia ribisnigri were detected. Cryptomyzus stachydis from Stachys silvatica and Galeopsis sp. was registered in Lithuania for the first time. Cryptomyzus maudamanti and Cryptomyzus galeopsidis are two morphologically very similar species, and in some cases it is difficult to identify them correctly. Cryptomyzus maudamanti was not found in Lithuania during this study period. Canonical discriminant function offered in the identification keys (Guldemond 1991a; Heie 1994) proved to be not reliable to discriminate between C. galeopsidis and C... [to full text]
13

Analysis of sexual dimorphism in human eye orbits using computed tomography

Lidstone, Laura J. 09 September 2011 (has links)
A plethora of anthropological studies have been undertaken on the skull, including many analyses of sexual dimorphism. Sexual dimorphism reflected in the eye orbits has not always demonstrated consistent or reliable results. However, recent studies (Pretorius, Steyn, & Scholtz, 2006; Ji et al., 2010) suggest some positive results utilizing geometric morphometrics to predict sex. Utilizing 97 post-mortem CT (computed tomography) scans, established morphological and metric techniques for sex determination were assessed from 3D rendered models of the crania. In addition, landmark data were collected on the orbital margin to evaluate the accuracy of sex determination using geometric morphometric techniques. Traditional methods demonstrated poor levels of accuracy for prediction of sex, however, utilizing generalised procrustes analysis and discriminant function analysis on 3D landmark data resulted in 94.95% overall accuracy. Application of recent methodological advances, including geometric morphometrics, should continue to be developed as it increases the ability to assess sexual dimorphism which will allow for greater identification of unknown remains.
14

Analysis of sexual dimorphism in human eye orbits using computed tomography

Lidstone, Laura J. 09 September 2011 (has links)
A plethora of anthropological studies have been undertaken on the skull, including many analyses of sexual dimorphism. Sexual dimorphism reflected in the eye orbits has not always demonstrated consistent or reliable results. However, recent studies (Pretorius, Steyn, & Scholtz, 2006; Ji et al., 2010) suggest some positive results utilizing geometric morphometrics to predict sex. Utilizing 97 post-mortem CT (computed tomography) scans, established morphological and metric techniques for sex determination were assessed from 3D rendered models of the crania. In addition, landmark data were collected on the orbital margin to evaluate the accuracy of sex determination using geometric morphometric techniques. Traditional methods demonstrated poor levels of accuracy for prediction of sex, however, utilizing generalised procrustes analysis and discriminant function analysis on 3D landmark data resulted in 94.95% overall accuracy. Application of recent methodological advances, including geometric morphometrics, should continue to be developed as it increases the ability to assess sexual dimorphism which will allow for greater identification of unknown remains.
15

Morphometric characteristisaiton of landform from DEMs

Wang, Daming, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2008 (has links)
Digital Elevation Models (DEMs) are fundamental datasets for environmental modelling. They provide the basic data from which terrain indices that represent or influence environmental phenomena are derived, for example slope gradient and hydrological contributing area, and also the source from which specific morphometric features are quantified and characterised, for example mountains and drainage basins. This thesis focuses on the latter, with the aim being to develop an algorithm to characterise the landscape in terms of five morphometric features (peaks, passes, pits, ridges and valleys) and to assess its validity and effectiveness for characterising landform from DEMs. The research in this thesis is divided into two parts. First, an algorithm of morphometric characterisation of landform from OEMs is developed based on a locally fitted quadratic surface and its positional relationship with the analysis window. Five requirements are taken into account within the algorithm: (1) the ideal cases of different morphometric features are simply and clearly defined; (2) the output is spatially continuous to reflect the inherent fuzziness of landform features; (3) the output is easily combined into a multi-scale index across a range of operational scales; (4) the standard general morphometric parameters can be easily quantified due to the easy calculation of first and second order derivatives from the quadratic surface; and (5) the algorithm is applicable to the different data structures used to represent DEMs. An additional benefit of the quadratic surface is the derivation of the R?? goodness-of-fit statistic, which allows both an assessment of the reliability of the results and the complexity of the terrain. Of the five morphometric features identified using the algorithm, valleys are perhaps the most commonly used. Therefore the second part of this thesis is a more detailed comparison between the Multi-Scale Valleyness (MSV) and three existing algorithms (D8, D∞ and MrVBF). D8 and D∞ are global flow accumulation algorithms, and perform well when characterising valley centre lines. However, they do not identify the valley areas themselves, although this is to be expected given their formulation. MrVBF focuses on characterising valley bottoms and so performs well when characterising valleys in broad and topographically flat areas. It does not identify valleys in the steeper upland parts of a catchment, although this too is something to be expected given its formulation. MSV directly characterises valley areas from a geomorphometric point of view, and performs well for both upland and lowland catchments, irrespective of their width. Overall, the results show that the single- and multi-scale terrain indices developed in this research perform well when characterising the five morphometric features. The approach has considerable potential for use in environmental modelling and terrain analysis.
16

Morphometric analysis of prenatally exposed children to anticonvulsant drugs

Doumit, Carmen 28 September 2016 (has links)
OBJECTIVE: To evaluate the morphometric effect of prenatal exposure to phenytoin, phenobarbital and carbamazepine on the shape of the maxilla the posterior and overall cranial base. MATERIAL AND METHODS: Sample selection: This study is a retrospective analyses of lateral cephalograms of 67 (Phenobarbital =21, Phenytoin=21, Carbamazepine=25) children age 6 to 16 who had been exposed prenatally to one of these drugs and compared to a control group of 44 unexposed children of the same age. Cephalometric films were digitized and anatomical landmarks identified by a single investigator. Landmarks were chosen to outline the maxilla, the posterior and overall cranial base. Morphometric analysis including Procrustes superimposition was used to compare the exposed children to the control group. Principal components analysis (PCA) and MANOVA tests were performed to determine the differences between the two groups. RESULTS: The superimposed average showed a significant difference between the two groups. In the exposed group, the anterior cranial base was vertically shorter. Glabella was more inferior and anterior relative to nasion, and the nasal tip was more superior and posterior. Orbitale was more inferior and posterior, suggesting a more posterior articulation with maxilla. The posterior cranial base was vertically taller and sagittally shorter. Also in the exposed group, the maxilla was vertically shorter. CONCLUSION: These results demonstrate a shorter, retrusive maxilla that articulates more posteriorly with a shorter anterior cranial base, confirming the midface hypoplasia of traditional anticonvulsant facies.
17

Systematické a ekologické studium netřesku Kindingerova (\kur{Sempervivum kindingeri} Adamović) / Systematics and ecology of Kindingers houseleek (\kur{Sempervivum kindingeri} Adamović)

HORNÁT, Milan January 2014 (has links)
There are many unanswered questions in the genus Sempervivum (Crassulaceae family). One of them is Sempervivum kindingeri from Macedonia. This species has not been revised yet since then he was found and described. In the last few years were published new floristic reports from the territory of Macedonia and Serbia and these reports indicate that discovered species belong to Sempervivum kindingeri. During 2012 and 2013 were some of the localities revised successfully and the live plants for research were collected there. Collected plants have been cultivated in comparative culture and afterwards they were used for morphometrical and karyological analysis. It was found that trichomes on the upper side of the leaf is the most important feature which allows to determine the species identity. Based on the obtained data it was found that plants descended from the high mountains of Macedonia and Serbia are probably a different taxon from S. kindingeri plants grown in culture.
18

Avaliação morfométrica e densitométrica dos fêmures de cordeiros Ile de France tratados com rações contendo silagem de milho ou cana-de-açúcar em dois níveis de concentrado

Veiga, Camila Anália de Castro [UNESP] 03 November 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-03Bitstream added on 2014-06-13T20:11:25Z : No. of bitstreams: 1 veiga_cac_me_jabo.pdf: 496208 bytes, checksum: fa8c791e09bae0f4ca9438b1bec550e1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram utilizados 20 cordeiros Ile de France machos não castrados, desmamados aos 15 kg de peso corporal, distribuídos em quatro tratamentos, sendo utilizados cinco animais por tratamento. As constituições das rações utilizadas nos tratamentos corresponderam a: T1 – ração com 60% de volumoso (silagem de milho) + 40% de concentrado; T2 – ração com 60% de volumoso (cana-de-açúcar) + 40% de concentrado; T3 – ração com 40% de volumoso (silagem de milho) + 60% de concentrado e T4 – ração com 40% de volumoso (cana-de-açúcar) + 60% de concentrado. Para a avaliação morfométrica, foi realizada a pesagem dos fêmures e avaliado o comprimento, o perímetro da epífise proximal e distal, bem como o da diáfise dos fêmures, o cálculo do índice de Seedor e a densidade mineral óssea dos respectivos tratamentos. Pode-se verificar no decorreer do período experimental que não ocorreram diferenças significativas nas avaliações morfométricas e densitométricas dos fêmures dos cordeiros dos diferentes tratamentos, com exceção da densidade da diáfise, que foi significativamente (p<0.05) maior no tratamento três (T3) em relação ao tratamento dois (T2) / We used 20 lambs Ile de France, intact males, weaned at 15 kg body weight, distributed in four treatments being used five animals per treatment. The constitutions of the diets used in treatments were as follows: T1 - feed containing 60% forage (corn silage) + 40% concentrate, T2 - feed containing 60% forage (sugar cane) + 40% concentrate; T3 - feed containing 40% forage (corn silage) + 60% concentrate and T4 - feed containing 40% forage (cane sugar) + 60% concentrate. For morphometric evaluation, were weighed and measured the femur length, the perimeter of the proximal and distal epiphysis and the diaphysis of the femur, the calculation of the index Seedor and bone mineral density of the respectives treatments. It can be verified during the experimental period there were no significant differences in morphometric and densitometric evaluations of the femurs of lambs of different treatments, except the density of the diaphysis, which was significantly (p <0.05) higher in treatment three (T3) in the treatment two (T2)
19

Diagnóstico ambiental da bacia hidrográfica do ribeirão Pederneiras – Pederneiras/SP / Environmental diagnosis of the hydrographic basin of Pederneiras stream - Pederneiras / SP

Garcia, Yara Manfrin [UNESP] 13 April 2017 (has links)
Submitted by Yara Manfrin Garcia null (yaramanfrin@hotmail.com) on 2017-06-09T02:46:12Z No. of bitstreams: 1 Tese_YaraGarcia_Final.pdf: 36120123 bytes, checksum: 80b84d2ec8ab20a742306e3dc7d42a28 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-06-13T14:00:42Z (GMT) No. of bitstreams: 1 garcia_ym_dr_bot.pdf: 36120123 bytes, checksum: 80b84d2ec8ab20a742306e3dc7d42a28 (MD5) / Made available in DSpace on 2017-06-13T14:00:42Z (GMT). No. of bitstreams: 1 garcia_ym_dr_bot.pdf: 36120123 bytes, checksum: 80b84d2ec8ab20a742306e3dc7d42a28 (MD5) Previous issue date: 2017-04-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O diagnóstico ambiental é a interpretação da situação ambiental com base na interação e dinâmica dos componentes relacionados ao meio físico. Constitui uma etapa fundamental no processo de gestão ambiental já que possibilita identificar os problemas e propor soluções sendo considerado assim, uma forma de planejamento ambiental. Nesse sentido, esta pesquisa teve como objetivo realizar o diagnóstico ambiental do meio físico da bacia hidrográfica do ribeirão Pederneiras, localizada nos municípios de Agudos e Pederneiras, no estado de São Paulo. Os procedimentos metodológicos foram baseados na estruturação de um banco de dados digital em ambiente de Sistema de Informação Geográfica visando à elaboração, atualização, interação e confecção dos mapas. A bacia hidrográfica do ribeirão Pederneiras possui uma área de 14918,28 ha e perímetro de 67,46 km, sendo considerada de 4ª ordem, com formato oblonga que indica baixa tendência a enchentes e baixa declividade. Com base nos resultados pode-se afirmar que a área é praticamente agrícola, dentre as doze classes de uso e ocupação do solo, a canade- açúcar é a cultura predominante com 6286,22 ha, seguido pelo reflorestamento com 5605,56 ha e, mesmo assim, merece destaque a área urbana que é de 1117,67 ha. Quanto as Áreas de Preservação Permanente, estas vêm sendo ocupadas inadequadamente e tem causado diversos problemas ambientais como, por exemplo, enchentes, assoreamentos e poluição dos cursos d’água, impermeabilização do solo, entre outros. Desta forma, com base nos resultados expostos, conclui-se a necessidade de medidas minimizadoras de problemas ambientais para a área urbana e rural e que tenham como base planos de ações e de controle desenvolvidos para nortear a aplicabilidade e fiscalização nessas áreas. Pretende-se que esse diagnóstico ambiental possa subsidiar o planejamento desta bacia hidrográfica pelo poder público e órgãos gestores. / Environmental diagnosis is the interpretation of the environmental situation based on the interaction and dynamics of the components related to the physical environment. Is a fundamental step in the process of environmental management since it makes possible to identify the problems and propose solutions being considered, therefore, a form of environmental planning. In this sense, this research aimed to carry out the environmental diagnosis of the physical environment of the Pederneiras hydrographic basin, located in Agudos and Pederneiras towns, in São Paulo State. The methodological procedures were based on the structuring of a digital database in a Geographic Information System Environment, aiming the elaboration, updating, interaction and preparation of the maps. The hydrographic basin area of the Pederneiras stream has an area of 14918,28 ha and a perimeter of 67,46 km, being considered of 4th order, with oblong format indicating low tendency to floods and low slope. Based on the results, it can be stated that the area is practically agricultural, among the twelve classes of land use and occupation, sugar cane is the predominant crop, with 6286,22 ha, followed by reforestation with 5605,56 ha and, even so, it is worth mentioning the urban area that is 1117, 67 ha. As for Permanent Preservation Areas, these have been inadequately occupied and this has caused several environmental problems, such as flooding, silting and pollution of watercourses, soil sealing, among others. In this way, based on the results presented, it is concluded that there is a need for minimizing environmental problems for the urban and rural areas and based on action and control plans developed to guide the applicability and supervision in these areas. it is intended that this environmental diagnosis can subsidize this hydrographic basin planning, by the public power and management organs. / CNPq: 140300/2014-7
20

Alterações neuropsicológicas e de morfometria cerebral de indivíduos com dislexia / Neuropsychological and brain morphometric changes of individuals with dyslexia

Lívia Ignacio de Freitas 23 October 2014 (has links)
A dislexia é um transtorno específico de leitura que consiste em um rendimento na leitura e na escrita inferior ao esperado para a idade cronológica, para nível de escolaridade e para o nível de inteligência, sendo a eficiência intelectual adequada (QI 80). Os principais comprometimentos envolvem habilidades de competências linguísticas como dificuldade de consciência fonológica, memória fonológica, discriminação e nomeação. Estudos apontam relação entre as dificuldades na leitura e na escrita e fatores neurobiológicos. O objetivo deste projeto foi investigar se existem diferenças entre morfometria cerebral através de segmentação automática para análise de espessura e volume e diferenças entre o desempenho cognitivo em testes neuropsicológicos do grupo de indivíduos com dislexia comparados com um grupo controle pareado. Foi realizado um estudo prospectivo no qual participaram 30 crianças, sendo 15 indivíduos com dislexia e 15 controles pareados por idade e por sexo. Foram avaliadas habilidades cognitivas tais como: eficiência intelectual, funções de atenção, habilidade visuoconstrutivas e habilidades de linguagem oral e escrita. A morfometria cerebral foi baseada em sequência T1 volumétrica de ressonância magnética e segmentação automática com medida da espessura e volume utilizando o pacote de software FreeSurfer. Na avaliação neuropsicológica, as habilidades que se mostraram mais prejudicadas foram aspectos da memória e da linguagem oral e escrita, tais como rebaixamento de span de memória operacional fonológica e dificuldade de fluência verbal, de associação e integração de ideias, de definição/conceitos, de nomeação e principalmente de consciência fonológica, de leitura e de escrita. As análises de neuroimagem sugerem alterações estruturais no cérebro do grupo clínico com redução no volume de substância cinzenta em regiões corticais, tais como lobo temporal inferior esquerdo e lobo temporal médio direito, e redução no volume de substância branca de ambos os hemisférios. Não foram identificadas alterações significativas na espessura. As alterações estruturais observadas através das técnicas de imagem podem estar relacionadas às funções cognitivas que se mostraram afetadas. / Dyslexia is a specific reading disorder that consists of a performance in reading and writing lower than expected for chronological age, educational level and for the level of intelligence, with an adequate intellectual efficiency (IQ 80 ). The main commitments involve abilities of language skills as difficulty in phonological awareness, phonological memory, discrimination and naming. Studies show link between difficulties in reading and writing and neurobiological factors. The objective of this project was to investigate whether differences in brain morphometry using automatic segmentation for the analysis of thickness and volume differences between cognitive performance on neuropsychological tests of the group of individuals with dyslexia compared with a control group. This is a prospective study in which 30 children participated, with 15 individuals with dyslexia and 15 controls matched by age and sex. Cognitive skills were evaluated as such: Intellectual efficiency, attention skill, visuo- constructive abilities and skills of oral and written language. Brain morphometry was based on sequence T1 volumetric MRI automatic segmentation and measurement of the thickness and volume using FreeSurfer software package. Neuropsychological skills that were more impaired were aspects of memory and oral and written language, such as flattening of phonological working memory span and difficulty in verbal fluency, association and integration of ideas, definitions / concepts, appointment and especially phonological awareness, reading and writing. Neuroimaging studies suggest structural changes in the brain with clinical group reduction in gray matter volume in cortical regions such as the left inferior temporal lobe and right middle temporal lobe, and a reduction in the volume of white matter of both hemispheres. No significant changes were identified in thickness. Structural changes observed through imaging techniques may be related to cognitive functions that have proven affected.

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