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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

Development, Evaluation and Refinement of a Body Mass Index Formula for Large Breed Canine Patients

Lodato, Dena Lynn 11 May 2013 (has links)
The current method of quantifying obesity in the veterinary patient is the subjective body condition score; however, scant research has focused on the development of an objective measurement. The present two part study evaluates the ability to create and refine an objective body mass index (BMI) formula for the large breed canine patient. In the first part of this study, seven morphometric measurements were obtained from seventy large breed dogs allowing the creation of five BMI formulas. In the second part of this study, computed tomography images were obtained from twenty-two dogs and the total percent body fat (TBF) was calculated. Results from the five formulas were compared to the calculated TBF to evaluate their accuracy. A final BMI formula was developed that has a very strong correlation with the TBF, and provides an objective measurement of obesity in the large breed canine patient.
2

A Comparative Study Between Genotypes and Ages of Eyes Using Morphometric Measures of Retinal Pigment Epithelial Cells

Folarinde, Micheal Shola 11 December 2012 (has links)
Aged-related macular degeneration (AMD) is a common eye condition among people older than 65 years and is a leading cause of vision loss. It gradually destroys the macula, the part of the eye that provides sharp, central vision needed for seeing objects clearly. This study aims to test the hypothesis that the morphology of retina pigment epithelium, a key site of AMD pathology, can reflect the various stresses aging and AMD progression impose. We first identify and separate the young and old age group for mouse eyes. Then we classify, the mouse eyes using two genotypes (C57BL/6L, RD10), and two age group (young, old).We show that without dimensional reduction, the cell area and shape measures do not provide good classification of the mouse eyes. But with the dimension reduction at the eye level, the cell area and shape measures provide excellent classification for mouse genotype and age.
3

A morphometric analysis of parturition scarring on the human pelvic bone

Decrausaz, Sarah-Louise 04 June 2014 (has links)
Osteological studies have identified scarring on the bone surface of the human pelvic bone as evidence of childbirth, termed parturition scarring. It remains unknown whether a single or multiple births cause parturition scarring. Such scarring has also been found on male pelvic bones. This study examines parturition scarring within the broader morphometric and musculoskeletal context of the pelves of both sexes. This project investigates the influence of body size (stature and body mass) and pelvic size (individual pelvic measurements and pelvic canal size) and shape (pelvic canal shape) on the presence of parturition scarring on the pelvic bones of females and males. Two skeletal collections of known-age and sex were chosen for this project on the basis of access to parity (childbirth) records: the Maxwell Museum Documented Skeletal Collection and the Christ Church, Spitalfields collection. The dimensions of articulated and disarticulated pelves, femoral measurements and scores for six types of parturition scarring were recorded for all individuals (n=292). Skeletal proxies for body mass and stature were calculated for all individuals. Univariate, bivariate and multivariate statistical analyses were used to identify significant differences in parturition scarring between sexes, correlation between body size variables, parity status, pelvic canal size and pelvic canal shape (as represented by principal components analysis) and parturition scarring. Parity status and pelvic canal shape do not associate with parturition scarring. Pubic tubercle variables associated variously with femoral head diameter and pelvic canal size in females or males only. Dorsal pitting correlates weakly with four pelvic dimensions in females. The results of this study suggest that the term parturition scarring should be revised to reflect its non-connection with parity status and that future investigations should examine musculoskeletal interactions based on body and pelvic size variation that affect the presence of such scarring in males. / Graduate / 0327 / 0287 / decrausa@uvic.ca
4

A morphometric analysis of parturition scarring on the human pelvic bone

Decrausaz, Sarah-Louise 04 June 2014 (has links)
Osteological studies have identified scarring on the bone surface of the human pelvic bone as evidence of childbirth, termed parturition scarring. It remains unknown whether a single or multiple births cause parturition scarring. Such scarring has also been found on male pelvic bones. This study examines parturition scarring within the broader morphometric and musculoskeletal context of the pelves of both sexes. This project investigates the influence of body size (stature and body mass) and pelvic size (individual pelvic measurements and pelvic canal size) and shape (pelvic canal shape) on the presence of parturition scarring on the pelvic bones of females and males. Two skeletal collections of known-age and sex were chosen for this project on the basis of access to parity (childbirth) records: the Maxwell Museum Documented Skeletal Collection and the Christ Church, Spitalfields collection. The dimensions of articulated and disarticulated pelves, femoral measurements and scores for six types of parturition scarring were recorded for all individuals (n=292). Skeletal proxies for body mass and stature were calculated for all individuals. Univariate, bivariate and multivariate statistical analyses were used to identify significant differences in parturition scarring between sexes, correlation between body size variables, parity status, pelvic canal size and pelvic canal shape (as represented by principal components analysis) and parturition scarring. Parity status and pelvic canal shape do not associate with parturition scarring. Pubic tubercle variables associated variously with femoral head diameter and pelvic canal size in females or males only. Dorsal pitting correlates weakly with four pelvic dimensions in females. The results of this study suggest that the term ‘parturition scarring’ should be revised to reflect its non-connection with parity status and that future investigations should examine musculoskeletal interactions based on body and pelvic size variation that affect the presence of such scarring in males. / Graduate / 0327 / 0287 / decrausa@uvic.ca
5

Morphometric Analysis of Gypsum Rillenkarren

Czok, Richard 04 1900 (has links)
Cross-section profiles of gypsum rillenkarren, obtained from a quarry near Gypsumville Manitoba, reveals a series of recently developed features. Statistical analysis of crest rillenkarren indicates a high degree of variability in the shape and size of the rills. In addition, abnormal differences between upper and lower rills can not be explained, but it is believed that the surrounding area may affect rill development. Comparing this study to previous rillenkarren studies, we find that rills from the quarry are undersized. This is due to many factors, chief of which may be the climatic conditions of central Manitoba and the relatively young age of the gypsum outcrops. / Thesis / Candidate in Philosophy
6

DXA vertebral morphometry studies in osteoporotic and healthy postmenopausal women

Rea, Jacqueline Ann January 1999 (has links)
No description available.
7

Análise morfométrica e variabilidade morfológica em populações de Syngonanthus nitens (Bong.) Ruhland (Eriocaulaceae) / Morfometric analysis and morphological variability in populations of Syngonanthus nitens (Bong.) Ruhland (Eriocaulaceae)

Watanabe, Mauricio Takashi Coutinho 02 October 2009 (has links)
Syngonanthus nitens (Bong.) Ruhland, espécie popularmente conhecida como capim-dourado, possui ampla distribuição no território brasileiro e apresenta um artesanato cujo interesse é voltado para seus escapos, caracteristicamente dourados. A identidade deste táxon é questionada, uma vez que são identificadas, como pertencentes à mesma espécie, plantas com padrões morfológicos muito distintos, tanto entre populações de diferentes partes do país, como entre populações simpátricas do Jalapão. Para investigar esta questão, foram analisados 23 caracteres morfológicos em 16 populações coletadas. As análises visavam avaliar a variabilidade morfológica dos espécimes no Parque Estadual do Jalapão, em Goiás e na Cadeia do Espinhaço. Para as análises morfométricas foram utilizadas técnicas de análise de agrupamento (UPGMA) e de ordenação (PCA e DF). Os resultados obtidos avaliando-se somente as populações coletadas no Jalapão evidenciaram a formação de dois grupos bem distintos, cuja separação foi fortemente influenciada pelo fator tamanho. Nas análises subsequentes, principalmente as que envolveram quase todas as populações coletadas, foram observadas continuidades e sobreposições entre estas, sem formação de grupos evidentes ou com alguma relação com a distribuição geográfica. Os caracteres não-florais mostraram-se mais informativos que os florais embora ambos tenham apresentando boa resolução. Devido aos resultados obtidos, às análises de materiais herborizados e à pesquisa literária específica, foi possível reconhecer para este complexo somente a espécie S. nitens, sem considerações infra-específicas. / Syngonanthus nitens (Bong.) Ruhland (common name \"Golden Grass\") is a widespread distributed species in Brazil. The handcrafts are made from scape of S. nitens, which are bright and gold in color. The identity of this taxon has been questionable, since plants with very different morphological patterns are identified as belonging to the same species. These individuals can occur in different populations, from distant parts of the country, and within sympatric populations, especially in Jalapão. In order to investigate this taxonomic problem, we analyzed 23 morphological characters in 16 populations. The analyses aimed to assess the morphological variability of the specimens in the Jalapão region (Central Brazil), in Goiás state and in the Range of Espinhaço. For morphometric analyses, we used cluster analysis (Unweighted Pair Group Method with Arithmetic Mean - UPGMA) and ordination (Principal Component Analysis - PCA and Discriminant Function - DF). When only individuals collected in Jalapão were evaluated, the results showed two very different groups, which where separated by size factor. In subsequent analyses, principally those involving almost all populations collected, we observed continuity and overlap between the morphological patterns. We did not identify isolated groups or any obvious correlation with geographical distribution. Although all characters had been informative to classify the individuals in their populations of origin, the non-floral characters were more informative than the flower traits. These results, together with the analyses of herbarium material and the specific literature, allowed to recognize this complex as the only one species, S. nitens, without infra-specific delimitations.
8

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

Freitas, Lívia Ignacio de 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.
9

Número total de neurônios no gânglio mesentérico caudal de cães domésticos nas diferentes fases do desenvolvimento. Qual o papel da idade na população total e no tamanho dos neurônios? / Total number of neurons in the dog´s caudal mesenteric ganglion in different phases of aging. What is the role of aging in the total number and size of neurons?

Gagliardo, Karina Martinez 23 December 2003 (has links)
O envelhecimento é caracterizado por um progressivo declínio na função neuronal envolvendo tanto o sistema nervoso central como o periférico. O aumento da idade é verificado por alterações no número e no tamanho dos neurônios. Contudo, estes dados são controversos e pouco conhecidos nos gânglios periféricos. Desta forma, o presente estudo teve como objetivo estudar o gânglio mesentérico caudal (GMC) de cães em dois períodos distintos do desenvolvimento (maturação e envelhecimento) a procura de alterações microestruturais no gânglio e alterações quantitativas e morfométricas nos neurônios presentes neste. A importância do GMC está ligada à inervação simpática do intestino grosso, esfíncter anal interno e parcialmente do aparelho urogenital. Para o estudo foram utilizados nove cães domésticos, sem raça definida e machos, provenientes do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo. Estes animais foram divididos em três grupos etários com idades bem definidas (1-2 meses, 1-3 anos e 5-10 anos). Os gânglios foram processados para o estudo da microscopia de luz e as análises morfométrica e estereológica foram, respectivamente, realizadas utilizando o software de análise morfométrica KS 400 ZEISS® e o método estereológico do disector físico. O aumento da idade foi caracterizado por uma maior quantidade de tecido não neuronal entre os neurônios e um aumento no volume do gânglio. O tamanho dos neurônios, expresso pela sua área seccional, também aumentou com a progressão da idade, encontrando nos animais mais velhos a presença de grânulos de lipofucsina no interior destes. A relação núcleo-citoplasma dos neurônios do GMC tende a diminuir com o envelhecimento. Quanto às alterações quantitativas, o número total de neurônios no GMC aumenta com a idade em cães adultos e senis, diferentemente da densidade neuronal (neurônios/mm3) que diminui com a progressão da idade. Através do peso corpóreo do cão foi possível predizer os valores das diferentes variáveis estereológicas verificadas neste trabalho, sendo os valores obtidos muito próximos aos reais. / The aging is characterized by a progressive decline of neuronal function that involves both the central and the peripheral nervous system. Aging process is accompanied by changes in the number and size of neurons. However, these data are controversial and poorly known in the peripheral ganglia. In this way, the present investigation aimed to study the dog\'s caudal mesenteric ganglion (CMG) in different phases of aging, looking for qualitative, quantitative and morphometric alterations in these neurons. The importance of the CMG is associated with the innervation of the lower large intestine, internal anal sphincter and partially the urogenital system. To the study, was used nine males, mongrel, domestic dogs from the Veterinary Hospital of the Veterinary and Zoöthecny College of the São Paulo University. They were divided into three different well defined aged groups (1-2 months old; 1-3 years old; 5-10 years old). The ganglia were processed for the light microscopy study. The morphometric and stereological analyses were, respectively, done using morphometric analyses software KS 400 Zeiss® and the stereological physical disector method. The increase of age was caractherized by a major amount of the non-neuronal tissue between the neurons and a increase of ganglion volume. The size of the neurons, represented by their sectional area, also increased with the age, being frequent, the presence of lipofucsin granules in old animals. The nucleus-citoplasmic relation of neurons of the CMG tend to decrease with the age. Referring to the quantitative changes, the total number of neurons in the CMG increased by aging in adults and elder dogs, differently of the neuronal density (neurons/mm3) which decreased with the aging. Through the body weight of the dog, it was possible to predict the values of the different stereological variables represented in this paper, where, the obtained values were close to the normal rates.
10

Aquisição e processamento de dados morfométricos derivados do modelo digital de elevação SRTM / Acquisition and processing of morphometric parameters derivatives from SRTM model

Steiner, Samar dos Santos 20 July 2007 (has links)
Os dados de SRTM são distribuídos com resolução espacial de 1arcsec (aprox. 30m) para áreas dentro dos EUA e de 3arcsec (aprox. 90m) para o resto do mundo. A resolução de 90m pode ser considerada apropriada para a análise em escalas pequenas e médias, mas é demasiadamente grosseira para trabalhos em detalhe. Uma alternativa para esta questão é a reamostragem do modelo SRTM; o processo não aumenta o nível de detalhe do modelo digital de elevação (MDE) original, mas conduz a uma superfície em que há uma maior coerência angular (isto é, declividade, orientação) entre pixels vizinhos, característica esta importante por se tratar da análise de terreno. O objetivo deste trabalho é mostrar como o ajuste apropriado do variograma e de parâmetros de krigagem (efeito da pepita e da distância máxima) podem ser utilizados nos valores que são empregados na interpolação visando obter resultados de qualidade na reamostragem de dados de SRTM de 3arcsec para 1arcsec. A análise morfométrica é utilizada como uma ferramenta auxiliar em estudos geológicos. O avanço dos sistemas de informação geográfica (SIG) e a disponibilidade de MDE\'s globais trouxeram maior agilidade e confiabilidade na avaliação dos parâmetros associados à superfície topográfica. Este trabalho faz uma comparação entre dois pacotes SIG mais utilizados na produção e Processamento de dados morfométricos, o projeto livre GRASS-GIS, e o software proprietário ESRI ArcGISTM. Foram analisados os parâmetros morfométricos como declividade, orientação de vertentes, rugosidade de terreno e superfícies de isobase. Os dados da elevação de SRTM 3arcsec foram reamostrados para 1arcsec e são utilizados como base para derivação dos parâmetros morfométricos. Os mapas de declividade e de orientação de vertentes produzidos pelo GRASS-GIS e pelo ArcGIS são equivalentes. O mapa de isobase mostrou diferenças significativas. As características principais podem ser identificadas em ambos os produtos, porém o mapa GRASS apresenta formas mais suaves e contornos mais naturais, enquanto o mapa gerado pelo ArcGIS mostra uma superfície com ruídos e diversas quebras bruscas. Este problema pode ser devido às diferenças de métodos de interpolação e à distribuição espacial dos dados, aglomerados ao longo das linhas de drenagem. No GRASS, a rugosidade de terreno pode ser facilmente calculada, enquanto no ArcGIS o usuário deve executar diversas operações. Ao contrário dos mapas de isobase, os mapas de rugosidade produzidos por ambos os software são muito similares, em função da provável distribuição regular dos pontos usados na interpolação. Se considerarmos todos os fatores que intervêm na qualidade dos produtos gerados como variograma, parâmetros de krigagem, a resolução do DEM, o valor de acumulação do fluxo e o método de interpolação, os mapas morfométricos produzidos serão equivalentes a um mapa interpretado manualmente por um especialista. / SRTM data is distributed at horizontal resolution of 1arcsec (aprox. 30m) for areas within the USA and at 3arcsec (aprox. 90m) resolution for the rest of the world. A 90m resolution can be considered suitable for small or medium-scale analysis, but it is too coarse for more detailed purposes. One alternative is to interpolate the SRTM data at a finer resolution; it won?t increase the level of detail of the original DEM, but it will lead to a surface where you find coherence of angular properties (i.e., slope, aspect) between neighbouring pixels, being this an important characteristic when dealing with terrain analysis. This work intends to show how the proper adjustment of variogram and kriging parameters -named the nugget effect and the maximum distance within which values are used in interpolation - can be set to achieve quality results on resampling SRTM data from 3arcsec to 1arcsec. Morphometric analysis is being used as an auxiliary tool in geological studies. Improvement of Geographic Information System (GIS) and availability of near-global digital elevation models (DEMs), have brought fastness and reliability in the assessment of parameters associated with the topographic surface. This work intends to make a comparison between two widely used GIS packages regarding production and manipulation of morphometric data, the Open-Source project GRASS-GIS and the proprietary ESRI ArcGISTM. The morphometric parameters Slope, Aspect, Surface Roughness and Isobase Surface were analyzed. SRTM 3arcsec elevation data was resampled to 1arcsec and used as base for deriving morphometric parameters. Slope and Aspect maps produced by GRASS-GIS and ArcGIS are equivalent. Isobase maps showed significant differences and the main features can be identified in both products. GRASS surface presents smoother forms and contours, while ArcGIS created a surface with noise and several step-like features. This problem can be due to differences of interpolation methods and the spatial distribution of data points, clustered along the stream lines. In GRASS, surface roughness can be easily calculated using a shell script, while in ArcGIS, the user must perform several operations. Unlike the isobase surface maps, roughness maps produced by both software are very similar, as a consequence of the regular distribution of data points used for interpolation. If all factors that intervene in the quality of generated products such as variograma and kriging parameters, DEM resolution, flow accumulation threshold and interpolation method were considered, produced morphometric maps will be equivalent to a map manually interpreted by an expert.

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