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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.
311

Caracterização de três populações de Ochlerotatus scapularis (Rondani, 1848) do eixo do Rio de Janeiro-São Paulo, utilizando marcadores genéticos e morfológicos. / Characterization of three populations of Ochlerotatus scapularis (Rondani, 1848) of the Rio de Janeiro-Sao Paulo, using morphological and genetic markers.

Petersen, Vivian Aparecida Ramos 14 December 2012 (has links)
Amostras populacionais de Oc. scapularis foram coletadas nos municípios de Tremembé-SP (TRE), São Paulo-SP (SPA) e Itaboraí-RJ (ITA). Foram empregados como marcadores biológicos: o gene mitocondrial Citocromo Oxidase Subunidade-1 (COI), geometria alar e análise da genitália masculina. Tais marcadores são tradicionalmente reconhecidos pelo poder discriminante em estudos desta natureza. As populações ITA, TRE e SPA mostraram-se distintas quanto à forma alar, sugerindo baixo fluxo gênico entre elas. Foi verificado dimorfismo sexual em relação ao tamanho isométrico, à forma alar e ao grau de diferenciação populacional. A população de ITA apresentou menor tamanho dos centróides que as demais populações estudadas. Foi verificado amplo polimorfismo genético, tendo sido detectados 51 haplótipos de COI e apenas 11 compartilhados entre as populações ITA, TRE e SPA. Quando comparados com as populações de estudo anteriormente realizado por Devicari, 2010 encontramos um padrão parecido. Analisando conjuntamente os presentes dados com aqueles obtidos por Devicari, 2010, computamos 52 haplótipos sendo apenas alguns compartilhados. Os valores do índice de diferenciação genética <font face=\"Symbol\">Fst observados foram moderados somente entre SPA e ITA, nas demais populações estudadas a diferenciação foi baixa, a diferenciação observada foi compatível com a hipótese de distanciamento geográfico das populações coletadas. Analisando cada marcador biológico, concluímos que as populações estudadas não se tratam de complexo de espécies. Ainda não descartamos a existência de complexo dentro de Oc. scapularis, porém, para definitiva resposta a essa questão serão necessários mais estudos envolvendo populações de outras regiões. / Samples of Oc. scapularis were collected in the municipalities of Tremembé-SP (TRE), São Paulo-SP (SPA) and Itaboraí-RJ (ITA). We used the following biological markers: mitochondrial cytochrome oxidase subunit-1 gene (COI), wing geometry and shape of male genitalia. These markers are traditionally known by its discriminating power in studies of this nature. ITA, SPA and TRE populations, showed distinct wing shape, suggesting low gene flow. We observed sexual dimorphism concerning the isometric size, wing shape and the degree of populational differentiation. ITA sample exhibited the lowest centroid sizes. We found high genetic polymorphism in all populational samples, being 51 COI haplotypes. Out of them, only 11 haplotypes were noted to be shared between at least two or three populations. When comparing our results with those of a previous survey conducted by Devicari (2010), we found a quite similar pattern of hign polymorfism. In total, both studies comprised 52 haplotypes. The <font face=\"Symbol\">Fst index of genetic differentiation values were considered \"moderate\" between ITA and SPA and \"low\" in the other comparisons. Present results are consistent with the hypothesis that populations are subjected to isolation by geographical distance. Analyzing together each biologcal marker, we conclude that populations studied do not consist a species complex. We do not rule out the possible occurence of a complex in Oc. scapularis, however, a definitive answer to this question will require further studies and sampling of populations from elsewhere.
312

Repercussões morfológicas dos efeitos da subnutrição protéica pré e pós-natal e da renutrição pós-natal sobre a mucosa palatina de ratos Wistar na fase púbere: avaliações morfométricas e da expressão do IGF-I e IGF-IR e da insulina e seu receptor / Morphologic repercussions of the protein malnutrition pre and postnatal and postnatal refeeding on the palatal mucosa of Wistar rats in the pubescent phase: structural evaluations and the expressions of the IGF-I and IGF-IR, Insulin and your receptor

Vono, Diana de Oliveira 17 February 2012 (has links)
Atualmente reagrupou-se sob o nome de subnutrição calórico-protéica uma série de afecções de carência antigamente descritas com diversos nomes e que tinham uma etiologia comum, a insuficiência alimentar, acarretando, ao mesmo tempo um emagrecimento e um esgotamento progressivo do estoque de proteínas do organismo. A partir de alterações na quantidade e qualidades dos alimentos ingeridos, o organismo busca regular seu metabolismo visando atingir a homeostase, na qual os hormônios desempenham papel fundamental. Dessa maneira, a desnutrição protéica e a secreção de insulina foram aqui correlacionados na avaliação morfológica e funcional do epitélio oral, representando, respectivamente, grave alteração nutricional (à semelhança da que acomete a população, especialmente, de países subdesenvolvidos e em desenvolvimento) e resposta produzida pela alteração do metabolismo energético das células. Os fatores de crescimento insulino-símile tipos 1 e 2 (IGF-I e IGF-II) são os principais fatores endócrinos determinantes do crescimento fetal. A maioria das ações conhecidas do IGF-I é mediada via um receptor tirosina-quinase, conhecido como IGF-IR. Recentemente, a insensibilidade ao IGF-I foi identificada como uma das causas de retardo de crescimento sem recuperação espontânea do desenvolvimento na vida pós-natal. Sendo assim, o presente trabalho tem o objetivo de estudar, através de métodos morfométricos, na mucosa palatina de ratos Wistar na fase púbere submetidos à desnutrição protéica pré e pós-natal e a renutrição pós-natal, o padrão celular e o componente colágeno da lâmina própria, bem como a expressão do IGF-I, do IGF-IR e da insulina e seu receptor, no intuito de encontrar possível correspondência entre as alterações metabólicas e morfofuncionais, decorrentes da depleção protéica. Para tanto, foram formados os seguintes grupos experimentais constituídos por animais heterogênicos (n=3) de acordo com a ração oferecida, protéica ou hipoprotéica: nutridos (N) e desnutridos (D) com 60 dias de idade, por ser essa a fase do final do período púbere, e renutridos (R), formado por animais do grupo D que, a partir do 21º dia (época do desmame) foram submetidos à ração protéica até atingirem 60 dias de idade. Os espécimes foram processados rotineiramente para microscopia de luz (HE, Azo-carmin e Pircro-sírius) e para imunohistoquímica (IGF-I, IGF-IR e insulina e seu receptor) e os dados morfoquantitativos analisados estatisticamente. Os resultados demonstraram que os parâmetros metabólicos tais como: alimentar, massa corporal, excreção de fezes, urina e ingestão de água, diferiram em todos os grupos semana após semana (S1&#8800;S2&#8800;S3&#8800;S4&#8800;S5&#8800;S6). A densidade de células epiteliais fora constatada pelo método de coloração H.E. e imunomarcadas com insulina e IGF-I e seus respectivos receptores. A subnutrição determinou um aumento significativo de células reativas a insulina (I) e seu receptor (IR) em relação ao grupo renutrido e nutrido (I: S &#8800;R; p<0.05) e (IR: S&#8800;N; S&#8800;R; p<0.05). O grupo R não obeteve aumento significativo de células imunomarcadas, assim, diferiu significativamente em relação ao grupo N para os hormônios IGF-I e seu receptor IGF-IR (R&#8800;N;p<0.05). O número de células da mucosa palatina modifica-se pouco na fase púbere e o seu desenvolvimento normal é sensível à depleção protéica, de modo que o tecido não é capaz de responder ao restabelecimento protéico. / Currently it has been grouped and named protein-caloric under nutrition a series of deficiency described in the past under several denominations with similar etiology, the food deficiency which leads simultaneously to a weight loss and progressive decrease of protein storage in the body. From the changes in the quantity and quality of ingested food, the organism tries to regulate its metabolism in order to homeostasis, in which the hormones play a fundamental role. This way, the protein under nutrition and the insulin secretion were here correlated in the morphological and functional evaluation of the oral epithelium representing high nutritional change (similarly to one which affect people specially from under developed countries) and response produced by changes in the energetic metabolism of the cells respectively. The grown factors insuline-símile type 1 and 2 (IGF-I and IGF-II) are the principal endocrine factors which determine the fetal growth. Many known actions of the IGF-I are mediated via tyrosine-kinase receptor known as IGF-IR. Recently, the insensibility to IGF-I was identified as one of the reason for the regrowth without abrupt recovery of the development in the post-natal life. Therefore, the present work aims to study, the cellular standard and the collagen of lamina propria, as well as the expression of the IGF-I, of the IGF-IR and the insulin and its receptor, using morphometric methods in the palatine mucosa of wistar rats in the pubertal phase subject to protein under nutrition pre and post natal and post-natal re-feeding with the objective of finding possible association between metabolic and morph functional changes coming from protein depletion. For this purpose, the following experimental groups were formed: heterogenic animals (n=3) according to the diet offered protein or hyperprotein diet: nourished (N) and undernourished (D) with 60 days of age (finish of pubertal phase), and re-nourished (R), formed by animals of D group that, from the 21st day (weaning day) were subject to protein diet up to 60 days of age. The specimens were processed routinely for light microscopy (HE, Azo-carmin and Pircro-sírius) and for immunohistochemistry (IGF-I, IGF-IR and insulin and its receptor) and the morph quantitative data statistically analyzed. The results demonstrate that the metabolic parameters such as: food, body mass, feces excretion, urine and water ingestion differ in all groups weekly (S1&#8800;S2&#8800;S3&#8800;S4&#8800;S5&#8800;S6). The density of epithelial was observed by HE method and immune-marked with insulin and IGF-I and their respective receptors. The under nutrition determined a significant increase of the cells reacting to insulin (I) and its receptor (IR) in relation to re-nourished and nourished groups (I: S &#8800;R; p<0.05) and (IR: S&#8800;N; S&#8800;R; p<0.05). No significant increase of immune-marked cells was observed in the R group, thus, differing significantly when comparing to N group for the hormones IGF-I and its receptor IGF-IR (R&#8800;N;p<0.05). The number of palatine mucosal cells has changed little in the pubertal phase and its normal development is sensitive to protein depletion, so the tissue cannot respond to the protein replacement.
313

Ecologia de foraminíferos bentônicos das regiões da Passagem do Drake e Ilha de Marambio, Península Antártica / Ecology of benthic foraminifera from regions of Drake Passage and Marambio Island, Antarctic Peninsula

Passos, Camila Cunha 01 August 2019 (has links)
A região da Península Antártica (PA) é importante para a circulação oceânica e o equilíbrio da temperatura global, além de ser detentora de grandes reservatórios de água doce e reservas de hidrocarbonetos e de hidrato de gás. Organismos bentônicos desses locais, como os foraminíferos, respondem de forma rápida a variações ambientais e são bastante utilizados em estudos de monitoramento mais precisos. Neste trabalho foram analisadas associações de foraminíferos em relação a parâmetros granulométricos e geoquímicos (elementos maiores e traço) de regiões ricas em hidrato de gás, situadas na PA. Para tal objetivo foram analisados sedimentos superficiais e subsuperficiais de: 1) região costeira (profundidade < 11 m) da Ilha de Marambio (IM), Mar de Weddell e 2) Passagem de Drake (PD). Na PD foram coletados 5 testemunhos (8 cm de comprimento) a 480 m de profundidade (D1) e 2 testemunhos (20 cm de comprimento) de 3800 m de profundidade (D2). Os valores de densidade e diversidade de foraminíferos encontrados aqui raramente são descritos na literatura para a região antártica. Contatou-se que as associações de foraminíferos da região da PA são constituídas por diversas espécies monotalâmicas e aglutinantes. A análise de agrupamento evidenciou associações com diferentes atributos ecológicos. Nas biocenoses da IM observou-se predominância de foraminíferos monotalâmicos de carapaça orgânica ou predominantemente orgânica (Psammosphaga magnetica e allogromiídeos), que apresentaram alta densidade e diversidade em sedimentos lamosos, ricos em nutrientes e valores elevados de oxigênio dissolvido. Já as biocenoses da região D1 apresentaram dominância de foraminíferos calcários, em particular de Epistominella exigua, indicadora de ambiente rico em fitodetritos. Nas tanatocenoses foram observadas predomínio de espécies aglutinantes como Deuterammina grisea e Cribrostomoides jeffreysii, com valores de densidade e riqueza aumentando da base ao topo em todos os testemunhos. Nos testemunhos da área D2, tanto na bio quanto a tanatocenose houve dominância de espécies típicas de ambiente hipóxico e rico em matéria orgânica (e.g., Adercotryma glomeratum e Spiroplectammina biformis) e baixos valores de densidade e riqueza. A morfometria das carapaças da Passagem de Drake (D1 e D2) apontou aumento significativo de A. glomeratum com a profundidade, provavelmente relacionado a adaptações a regiões profundas e a estabilidade ambiental. A Análise de Componentes Principais revelou que oxigênio dissolvido do sedimento, granulometria, porcentagem de CaCO3, concentração de potássio (D1), bem como concentrações de elementos maiores e traços (D2) foram as principais variáveis que influenciaram a distribuição das espécies. Não foi possível identificar alterações nas associações e em relação aos padrões ecológicos, devido às emanações de hidrato de gás. Assim, ressalta-se a necessidade da realização de mais estudos, como análises morfológicas e químicas das carapaças dos foraminíferos, principalmente em espécies aglutinantes, ainda mais em regiões como a PA, reconhecidamente mais sensível as mudanças climáticas e de enorme importância para o equilíbrio do clima da Terra / The Antarctic Peninsula (PA) region is essential for ocean circulation and global temperature equilibrium, as well as having large freshwater reservoirs, hydrocarbon and gas hydrate reserves. Benthic organisms from these locations, such as foraminifera, respond rapidly to environmental variations and are widely used in more accurate monitoring studies. In this work, foraminifera associations were analyzed concerning granulometric and geochemical parameters (major and trace elements) of regions rich in gas hydrate, located at AP. For this purpose, surface and subsurface sediments were analyzed from 1) coastal region (depth <11 m) of Marambio Island (IM), Weddell Sea and 2) Drake Passage (PD). In PD five cores (8 cm long) were collected at 480 m depth (D1) and two cores (20 cm long) at 3800 m depth (D2). Foraminifera density and diversity values found here are rarely described in the literature for the Antarctic region. The results of foraminifera associations in the PA region are composed of several monothalamic and agglutinant species. Cluster analysis showed associations with different ecological attributes. In MI biocenosis there was a predominance of monothalamic foraminifera of organic or predominantly organic tests (Psammosphaga magnetica and allogromiidae), with high density and diversity in muddy sediments, rich in nutrients and high values of dissolved oxygen. On the other hand, the biocenosis of the D1 region was dominated with calcareous foraminifera, in particular, Epistominella exigua, indicating an environment rich in organic matter. In the thanatocoenosis, agglutinating species such as Deuterammina. grisea, and Cribrostomoides jeffreysii predominated, with density and richness increasing from bottom to top in all cores. In the D2 area, both in bio as well as in thanatocoenosis, there was a dominance of typical species of hypoxic environments and rich in organic matter (e.g., Adercotryma glomeratum and Spiroplectammina biformis), and low density and richness values. The morphometry from DP (D1 and D2) showed a significant increase in size of A. glomeratum with depth, probably related to deepsea adaptations and environmental stability. Principal Component Analysis revealed that dissolved oxygen in sediment, granulometry, CaCO3 percentage, potassium concentration (D1) as well as major and trace elements concentrations (D2) were the main variables that influenced species distribution. It was not possible to identify changes in organisms and the relation to ecological standards due to gas hydrate. Thus, further studies are necessary, such as morphological and chemical analysis of foraminifera tests, especially in agglutinating species, even more so in regions such as PA, which are known to be more sensitive to climate change and of great importance to the Earth\'s climate balance
314

Group comparison of diffusion fractional anisotropy using self-made brain template of Taiwan adolescents¡GApplication on attention deficit hyperactivity disorder

Guo, Sz-Han 29 December 2011 (has links)
Attention deficit/hyperactivity disorder (ADHD) is a common disease with a worldwide prevalence of 5% on preschool children. It has been reported that ADHD patients have volume variant in partial brain regions. Futhermore, functional magnetic resonance imaging have also been used to detect function variant possibility in particular brain regions. In the last decade, some researchers used diffusion MR imaging to investigate the abnormality of neural fibers in disease involved with central nervous system. In general, the diffusion anisotropy of white matter in both ADHD patients and healthy subjects can be estimated seperately to undergo inter-subject comparison. While previous studies often used the popular ICBM brain template (MNI152), this study applied a self-made template of Taiwan adolescents as the common space of image normailization. In this work, group comparison of diffusion fractional anisotropy was performing by using two methods, TBSS and VBM. Both manners found a decreased FA in white matter of ADHD subjects compared with normal control group. However, regions detected by different methods showed low reproducibility. The areas of significant difference include inferior longitudinal fasciculus¡Binternal capsule¡Bexternal capsule¡Bsuperior longitudinal fasciculus¡Boptic radiation¡Bsuperior frontal¡Bsuperior region of corona radiata¡Bcorticospinal tract¡Bposterior region of corona radiata / superior longitudinal fasciculus¡Bsuperior fronto-occipital fasciculus¡Banterior region of corona radiata¡Bgenu of corpus callosum nerve fibers.
315

Investigation on white-matter abnormalities in attention deficit hyperactivity disorder using diffusion tensor imaging

Huang, Sheng-po 22 October 2009 (has links)
Attention deficit hyperactivity disorder (ADHD) is a neurobehavior developmental disorder that affects around 7.5% of Taiwan children. With the use of magnetic resonance imaging , many results have been reported that ADHD patients have volume atrophy in gray matter and dysfunction in couples of cortical regions. In recent years, diffusion MR imaging with diffusion-sensitizing gradients has been used to investigate the abnormality of neural fibers in disease involved with central nervous system. In this study, the anisotropy of white matter in both ADHD patients and age-matched healthy subjects was estimated using diffusion tensor imaging to undergo inter-subject comparison. In this work, a significant decrease (FWE-corrected p-value <0.05) of FA values has been found in white matter of adolescents diagnosed as ADHD patients, compared with normal controls group. The areas that confirmed by two different algorithms of inter-subject comparison are mainly diffused on white matter region, including middle cerebellar peduncle, left inferior longitudinal fasciculus, internal capsule, left optic radiation, external capsule, splenium of the corpus callosum, superior longitudinal fasciculus, superior frontal and parietal-occipital nerve fibers.
316

Ontogeny and Littoral Structure of Lakes Created on Phosphate Mined Lands of Central Florida

Mitraki, Chrysoula 01 January 2012 (has links)
Created lakes are an end product of phosphate mining in Florida. Beginning in 1975, Florida reclamation rules set criteria for phosphate created lakes aiming to approximate the structure of natural lakes, and emphasizing extensive littoral zones with both emergent and submersed vegetation. Lake development relative to lake age and design were examined for 22 phosphate lakes representing a 40-year age trajectory, utilizing water quality and benthic invertebrate communities from littoral and deep-water locations (Chapter 1). The relative importance of morphometry and lake age in the development of littoral plant communities was examined using multiple vegetation surveys throughout the year, in a separate investigation of 39 littoral locations from 13 lakes reflecting age and morphometry gradients (Chapter 2). The same littoral locations were used to investigate benthic community composition in relation to emergent and submersed plant habitats (depth of 0.5 m and 1.5 m respectively), water quality, sediment characteristics, morphometry and lake age (Chapter 3). Phosphate lakes >5.5m deep are warm monomictic water bodies, stratifying from April to October/November, and developing thermoclines at approximately 4 m. Shallow lakes (<5.5 m deep) are polymictic. Phosphate lakes become eutrophic or hypertrophic immediately after creation and remain so through time. Unlike reservoirs, they do not go through a trophic surge, which is an initial period of great productivity that declines as sediment nutrient storage is exhausted. Among the 22 sampled lakes, epilimnetic physical and chemical water quality variables (Secchi depth, chlorophyll a, turbidity, pH) did not differ along the age trajectory. Only specific conductance declined significantly, 10-20 years after lake creation, most probably due to bank stabilization. All water quality variables were within the range of natural lakes in the region, and were most similar to urban rather than suburban or rural natural lakes. Benthic invertebrate abundance (total, Chironomidae, Oligochaeta, invertebrates other than Chironomidae and Oligochaeta) and taxa richness displayed great variability with lake age and did not differ among decadal lake groups at any depths examined (1 m, deepest point). Invertebrate abundance did not differ between littoral and deep habitats, except for lakes >10 years old, where littoral abundance was greater than deep-water abundace, suggesting faster colonization of the littoral zone. Littoral taxa richness was greater than richness in deep-water, which was attributed to taxa other than Chironomidae and Oligochaeta. Deep-water and most littoral habitats were dominated by Chironomidae, whereas Oligochaeta were occasionally dominant in the littoral zone. Dissolved oxygen was the variable explaining most variance of both littoral abundance and richness. Littoral macrophyte communities in phosphate lakes differed from natural Florida lakes. Although most phosphate lakes developed emergent littoral zones, submersed vegetation was absent, with few exceptions of the non-indigenous Hydrilla verticillata. Plants clustered in groups reflecting their hydrological designations. Frequently encountered plants classified either in the obligate wetland plant group, characterized by Typha, and inhabiting mostly intermediate-age lakes or the facultative wetland plant group, characterized by Panicum repens. Most plants in the latter group were bimodally distributed in youngest and oldest lakes, whereas few plants were ubiquitous. Littoral plant community composition was determined by both lake morphology and age, but the relative influence of these two components was not clear. Littoral plant composition was a good predictor of lake development. Morphometric (slope) and sediment characteristics (organic content, particle size) did not differ between the two littoral depths examined (0.5 m and 1.5 m). Slope correlated moderately but significantly with lake age, and organic content was low in all samples. Total littoral benthic invertebrate abundance and its major component Chironomidae, started from low values at newly created lakes and remained low or increased unpredictably with time. Total, Chironomidae, Oligochaeta and Gastropoda abundances did not differ between the depths of 0.5 m and 1.5 m, whereas taxa richness and the abundance of invertebrates other than Chironomidae, Oligochaeta, and Gastropoda was greater at the shallower depth (0.5 m).The relative effect of lake morphology versus age on benthic invertebrate composition was not clear. Total and Chironomidae abundance increased with lake age at 0.5 m, and bank slope at 1.5 m. Both littoral invertebrate abundance and richness in phosphate lakes were lower than in a natural, mesotrophic, macrophyte-dominated lake in the region, characterized by great Oligochaeta densities.
317

Predictions Within and Across Aquatic Systems using Statistical Methods and Models / Prediktioner inom och mellan akvatiska system med statistiska metoder och modeller

Dimberg, Peter H. January 2015 (has links)
Aquatic ecosystems are an essential source for life and, in many regions, are exploited to a degree which deteriorates their ecological status. Today, more than 50 % of the European lakes suffer from an ecological status which is unsatisfactory. Many of these lakes require abatement actions to improve their status, and mathematical models have a great potential to predict and evaluate different abatement actions and their outcome. Several statistical methods and models exist which can be used for these purposes; however, many of the models are not constructed using a sufficient amount or quality of data, are too complex to be used by most managers, or are too site specific. Therefore, the main aim of this thesis was to present different statistical methods and models which are easy to use by managers, are general, and provide insights for the development of similar methods and models. To reach the main aim of the thesis several different statistical and modelling procedures were investigated and applied, such as genetic programming (GP), multiple regression, Markov Chains, and finally, well-used criteria for the r2 and p-value for the development of a method to determine temporal-trends. The statistical methods and models were mainly based on the variables chlorophyll-a (chl-a) and total phosphorus (TP) concentrations, but some methods and models can be directly transferred to other variables. The main findings in this thesis were that multiple regressions overcome the performance of GP to predict summer chl-a concentrations and that multiple regressions can be used to generally describe the chl-a seasonality with TP summer concentrations and the latitude as independent variables. Also, it is possible to calculate probabilities, using Markov Chains, of exceeding certain chl-a concentrations in future months. Results showed that deep water concentrations were in general closely related to the surface water concentrations along with morphometric parameters; these independent variables can therefore be used in mass-balance models to estimate the mass in deep waters. A new statistical method was derived and applied to confirm whether variables have changed over time or not for cases where other traditional methods have failed. Finally, it is concluded that the statistical methods and models developed in this thesis will increase the understanding for predictions within and across aquatic systems.
318

MORPHOMETRIC ANALYSIS OF THE SHEEP THORACOLUMBAR SPINE USING COMPUTED TOMOGRAPHY AND A COMPARISON WITH THE HUMAN CORRELATE

Mageed, Mahmoud 20 November 2014 (has links) (PDF)
Sheep are commonly used as animal model for in vivo testing of new spinal implants as well as surgical procedures. Therefore, extensive knowledge of the precise morphometry and biomechanics features of sheep spine is crucial for experimental design and interpretation of results obtained in these trials. Little is known about the sheep spine. Therefore, the current study, which comprises of two parts, aimed to gain more knowledge concerning the morphometry of sheep thoracolumbar spine. The first part aimed to document the morphometry of the sheep thoracolumbar vertebrae and to assess the feasibility of using sheep lumbar vertebrae as a model for human spine researches based on morphometric comparison. For this reason, computed tomographic (CT) scanning was carried out in five clinically healthy female Merino sheep (2 years, 62 ± 5.3 kg) under general anaesthesia. CT images were reformatted with 1-mm slice thickness from T2 through L6. The CT images were reformatted in transverse and sagittal planes using multiplaner reconstruction algorithm. Subsequently, CT images were transferred to a workstation and reviewed with dedicated software for measuring the dimensions of the vertebral bodies, spinal canal, intervertebral disc, and pedicles. Based on the generated morphometric data of the sheep lumbar vertebrae, four spinal indices and Pavlov’s ratio were calculated as well as the volume of the vertebral bodies. The spinal indices were concavity index, endplate index, spinal canal index and pedicle index. For measuring vertebral body volume, the transverse CT data were reformatted in 5-mm slice thickness and imported in dedicated software. Thereafter, the four spinal indices and the volume were compared to human published data. The parameter was defined comparable if the ratio sheep/human of each individual vertebra showed variation less than 20%. The second part of the current work aimed to provide quantitative morphometric data of the thoracolumbar dural sac and describe the anatomical relationship between the dural sac and its surrounding osseous structures of the spine. To achieve these aims, computed assisted myelography was carried out in five adult female blackhead sheep (2.0 ± 0.4 years, 80.6 ± 28.7 kg) under general anaesthesia. Transverse images were acquired with 2-mm slice thickness from T1 to L6. Sagittal and transverse diameters and cross-sectional area of the dural sac and the spinal canal were measured on CT images. To determine the anatomical relationship between the dural sac and osseous structures of spinal canal, the pedicle-dural sac distance and available space for dural sac were calculated. The morphometric data showed that the sheep thoracolumbar vertebral bodies and the spinal canal were wider than they were deep, most obviously in the lumbar vertebrae. The intervertebral discs were as much as 57.4% thicker in the lumbar than in the thoracic spine. The pedicles were higher and longer than they were wide over the entire thoracolumbar spine. Compared to humans, sheep lumbar vertebral body volumes were 48.6% smaller. The comparison of absolute values between both species revealed that sheep had smaller, longer and narrower vertebral bodies, thinner intervertebral discs, narrower spinal canal and narrower, higher pedicles. The comparison of the spinal indices showed a good comparability to human in terms of the vertebral endplate and spinal canal. The results of the second parts showed that the dural sac area covered 45.9% and 49.0% of the thoracic and lumbar vertebral canal area, respectively, and it is significantly (positive) correlated with the transverse diameter as well as area of the vertebral canal. The pedicledural sac distance in the lumbar vertebrae was up to 15.8% larger than in the thoracic ones. The clinical relevance of the current study, the sheep lumbar spine has good comparability to that of humans in terms of the vertebral endplate regions and spinal canal, suggesting that a sheep spinal model would be appropriate for studying artificial intervertebral discs, implantation of intervertebral fusion, etc. With regard to sheep pedicles, can be used as a model for spinal implant conditioned by adaptation of implant size to sheep pedicel dimensions. The lumbar vertebral canal shows more space for the dural sac, which seems to be safer for testing fixation spinal implants. / Schafe werden häufig als Tiermodell für In-vivo-Versuche verwendet, um neue Wirbelsäulenimplantate sowie chirurgische Prozeduren zu testen. Daher ist die umfassende Kenntnis der präzisen Morphometrie und der biomechanischen Merkmale der Schafwirbelsäule entscheidend für das experimentelle Design und die Interpretation der Ergebnisse in den Studien. Es sind wenige Daten über die Schafwirbelsäule bekannt. Auf Grund dessen zielt die aktuelle Studie darauf ab, mehr Wissen über die Morphometrie der thorakolumbalen Wirbelsäule von Schafen zu gewinnen. Der erste Teil dieser Studie soll die Morphometrie der Brust- und Lendenwirbelsäule dokumentieren. Das Ziel besteht darin, die Verwendung von Schaflendenwirbeln als Modell für die menschliche Wirbelsäule im morphometrischen Vergleich beurteilen zu können. Aus diesem Grund wurden Computertomographische Untersuchungen (CT) von fünf klinisch gesunden weiblichen Merino-Schafen (2 Jahre, 62 kg ± 5,3 kg) unter Allgemeinanästhesie durchgeführt. Die CT-Bilder wurden mit einer Schichtdicken von 1 mm aus T2 bis L6 gewonnen. Anschließend wurden die CT-Bilder in der transversalen und sagittalen Ebene multiplanar reformatiert. Danach wurden Messungen und Bewertungen mit einer geeigneten Software an den Wirbelkörpern, Wirbelkanälen, Bandscheiben und Pedikeln durchgeführt. Basierend auf den erzeugten morphometrischen Daten der Schaflendenwirbel wurden vier Wirbelsäulen-Indizes und Pavlov’s-ratio sowie das Volumen der Wirbelkörper berechnet. Die Wirbelsäulen-Indizes stellten den Konkavitäts-, Endplatten-, Spinalkanal- und Pedikel-Index dar. Für die Messung des Volumens von Wirbelkörpern wurden die transversalen CT-Daten in 5 mm Schichtdicke formatiert und in geeignete Software eingefügt. Danach wurden die vier Indizes-Wirbelsäulen und das Volumen der Lendenwirbelkörper mit den veröffentlichten Daten von menschlichen Wirbeln verglichen. Sie wurden als „vergleichbar“ definiert, wenn das Verhältnis Schaf-Mensch jedes einzelnen Wirbels Variationen von weniger als 20 % aufwies. Der zweite Teil der vorliegenden Arbeit hat zum Ziel, quantitative morphometrische Daten des thorakolumbalen Duralsacks zu ermitteln. Weiterhin sollen die anatomischen Beziehungen zwischen dem Duralsack und seinen umliegenden knöchernen Strukturen der Wirbelsäule beschrieben werden. Dazu wurden CT-Myelographien an fünf erwachsenen weiblichen Schwarzkopfschafen (2 Jahre ± 0,4 Jahre, 80,6 kg ± 28,7 kg) unter Allgemeinanästhesie durchgeführt. Transversale CT-Bilder wurden mit 2 mm Schichtdicke von T1 bis L6 gemessen. Sagittal- und Transversal-Durchmesser sowie die Querschnittsfläche von Duralsack und Wirbelkanal wurden auf CT-Bildern gemessen. Um die anatomische Beziehung zwischen dem Duralsack und den knöchernen Strukturen des Wirbelkanals zu ermitteln, wurden der Pedikel-Duralsack-Abstand und das Platzangebot für den Duralsack berechnet. Die Wirbelkörper und der Wirbelkanal der ovinen thorakolumbalen Wirbelsäule sind breiter als tief, vor allem im Bereich der Lendenwirbel. Die Bandscheiben sind in der Lendenwirbelsäule 57,4 % dicker als in der Brustwirbelsäule. Die Pedikel der Brust- und Lendenwirbelsäule waren höher und länger als breit. Im Vergleich zum Menschen ist das Volumen von Schaflendenwirbelkörpern 48,6 % kleiner. Der Vergleich der absoluten Werte zwischen den beiden Spezies ergab, dass Schafe kleinere, längere und schmalere Wirbelkörper, dünnere Bandscheiben, einen schmaleren Spinalkanal und schmalere, höhere Pedikel besitzen. Der Vergleich der Wirbelsäulen-Indizes zeigte eine gute Vergleichbarkeit mit menschlichen Wirbelendplatten und Wirbelkanälen. Im zweiten Teil der Studie konnte festgestellt werden, dass die Duralsackfläche 45,9 % des Brustwirbelkanals und 49,0 % des Lendenwirbelkanals einnimmt. Die Duralsackfläche korreliert deutlich positiv mit dem Querdurchmesser und der Fläche des Wirbelkanals. Der Pedikel-Duralsack-Abstand in der Lendenwirbelsäule war bis zu 15,8 % größer als in der Brustwirbelsäule.
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Morphometrische Untersuchung des Wachstums beim Alpaka (Vicugna pacos) von der Geburt bis zu einem Alter von 36 Monaten / Morphometric evaluation of the growth of Alpacas (Vicugna pacos) from birth to 36 months of age

Grund, Sarah 03 June 2014 (has links) (PDF)
Außerhalb ihrer ursprünglichen Heimat in Südamerika steigt die Anzahl der Alpakas stetig an. Die Tiere erfreuen sich auch in Deutschland einer großen Beliebtheit. Aktuellen Schätzungen zufolge leben in Deutschland circa 10.000 Alpakas. Siewerden zur Wollgewinnung, sowie als Begleit- und Therapietiere in kleinen Hobbyhaltungen oder in Beständen mit einer Herdengröße von bis zu 150 Tieren gehalten. Damit verbunden werden auch zunehmende Ansprüche an die Qualität der tierärztlichen Betreuung dieser Neuweltkameliden gestellt. Die Beurteilung des Wachstums und der Entwicklung junger Alpakas bildet dabei, genauso wie im Rahmen der Zucht, eine wichtige Grundlage. Derzeit existieren nur unzureichende Informationen über den Wachstumsverlauf beim Alpaka. Bisher dienten proportional angepasste Daten vom Lama zur Orientierung. Das Ziel dieser Arbeit ist die auf morphometrischen Daten basierende Beschreibung der physiologischen Entwicklung des Skelettes und des Körpergewichtes beim Alpaka in den ersten 36 Lebensmonaten. Weiterhin soll untersucht werden, welche Faktoren Einfluss auf das Wachstum junger Alpakas haben. Die Bestimmung einer Gleichung zur Berechnung des Körpergewichtes stellt einen weiteren Schwerpunkt der Arbeit dar. Über einen Zeitraum von 12 Monaten wurden 162 Alpakas im Alter von wenigen Tagen bis zu 36 Monaten vermessen. In einem zweiwöchentlichen Rhythmus wurden 9 verschiedene Parameter bei jedem Tier erfasst: Gewicht, Widerristhöhe, Hüfthöhe, Rückenlänge, Rumpflänge, Tuberculum majus-Olecranon-Distanz (TOD), Basis patellae-Tuber ischiadicum-Distanz (BTD), Thoraxumfang und Body Condition Score. Mit Hilfe von speziell angefertigten Messschiebern, einer digitalen Waage und einem flexiblen Maßband erfolgte die Datenerhebung am stehenden Tier. Das Wachstum beeinflussende Faktoren wurden mittels Allgemeiner Untersuchung der Tiere, stichprobenartigen Kotprobenuntersuchungen, Futtermittelanalysen und vom Halter ausgefüllten Fragebögen erfasst. Die erhobenen Messwerte wurden unter Verwendung der nichtparametrischen Regression LOESS (locally weighted scatterplot smoothing) zur Erstellung von Wachstumskurven genutzt, die den durchschnittlichen Wachstumsverlauf des Körpergewichtes, sowie verschiedener Körpermaße von bis zu 36 Monate alten Alpakas darstellen. Sie ermöglichen die Beurteilung der körperlichen Entwicklung eines Alpakas. Unter Anwendung der LMS-Methode (Schiefe der Verteilung der Messwerte λ [L], Mittelwert M, Standardabweichung S) wurden Perzentilkurven von vier Parametern erstellt, die als Referenzkurven und Richtlinien zur Beurteilung der tierartspezifischen Größe und des Gewichtes genutzt werden können. Wachstumsprognosen und Rückschlüsse auf das Alter eines Alpakas sind mit Hilfe der Perzentilkurven möglich. Sowohl die Wachstumskurven als auch die Perzentilkurven lassen erkennen, dass Alpakas mit 36 Monaten noch nicht ausgewachsen sind. Die Kurven wurden anhand von Messwerten von Alpakas erarbeitet, die unter Bedingungen gehalten wurden, die keinen beziehungsweise einen minimalen Einfluss auf das Wachstum haben. Dies ist anhand der Ergebnisse der parasitologischen Untersuchungen und der Futtermittelanalysen erkennbar. Weitere Auswertungen der Messdaten zeigen, dass keine signifikanten Entwicklungsunterschiede zwischen Hengsten und Stuten beziehungsweise zwischen der Rasse Huacaya und der Rasse Suri bestehen. Ähnlich wie bei anderen Tierarten auch, eignet sich der Thoraxumfang zur zuverlässigen Berechnung des Körpergewichtes besonders gut. Eine große Korrelation besteht auch zwischen der Rumpf- beziehungsweise der Rückenlänge und dem Körpergewicht. Praktische Bedeutung haben die Erkenntnisse dieser Arbeit vor allem für Alpakazüchter und –halter, sowie für Veterinärmediziner. Die Ergebnisse bilden eine wichtige Grundlage für das Fütterungs- und Reproduktionsmanagement beim Alpaka. / The number of alpacas bred outside their natural habitat in South America increases continuously. Alpacas become more and more popular in Germany. According to recent estimates about 10.000 alpacas live in Germany. They are used for wool production, as companion animal and for therapeutic treatments. The alpacas are kept as pets in smaller groups or as livestock in herds of up to 150 animals. Due to the rising number of these camelids in Germany and more intense use, higher demands on the quality of veterinary care of alpacas occur. Knowledge and data on growth and development in young alpacas are essential for an objective health evaluation as well as for breeding management. Currently very limited information is available on growth of alpacas and the data published have been adapted by calculation using measurements performed on llamas. The primary objective of this study was to determine the physiological development of the skeleton and the body weight of alpacas from birth until 36 months of age based on morphometric data. An additional aim was to analyze factors that influence the growth of young alpacas. A third focus of this study was to generate a mathematical formula to calculate the body weight. The measurements were performed on 162 alpacas with an age ranging from the first day of life up to 36 months. For each alpaca nine different parameters were determined every two weeks: body weight, height at withers, height in the hip, thoracic circumference, length of the back, length of the trunk, Greater tubercle-Olecranon-distance (TOD), Base of the patella-Ischial tuber-distance (BTD) and body condition score. All measurements were carried out on standing animals. Three custom designed caliper gauges, a digital balance and a flexible measuring tape were used to obtain the nine parameters. Factors that influence growth were captured by clinical examination, randomized fecal samples, analysis of forage and a questionnaire completed by the breeder. Based on the data collected growth curves were developed using the nonparametric regression LOESS (locally weighted scatterplot smoothing). These curves represent the average growth pattern of body weight and various body measurements of up to 36 months old alpacas. Using theses curves the physical development of this species can be assessed. By applying the LMS-Method (skewness of the measurement distribution λ [L], mean M, coefficient of variation S) percentile curves of four different parameters have been generated. They can serve as reference curves and as guidelines for objective evaluation of species specific size and weight. Using the percentile curves a reliable prediction of growth or conclusions regarding the age of an alpaca are possible. The growth curves as well as the percentile curves show that alpacas are not mature at the age of 36 months. The curves are based upon data from alpacas who were raised under environmental conditions which have no or minimized influence on growth. This is evident in the results of the parasitological examinations and the feed analysis. Further analyses indicate that no significant differences in growth exist between males and females respectively between the two breeds Huacaya and Suri. Like in other species the thoracic circumference is particularly suitable for estimating the body weight. A strong correlation exists between body weight and the length of the trunk as well as the length of the back. The results of this study are of practical significance for alpaca owners, breeders and veterinarians. They provide a sound basis for recommendations in feeding and management of reproduction.
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Morphometrische Analyse der Kieferbezahnung fossiler wie rezenter carcharhinider Selachier / morphometric analysis of jaw teeth of fossil and extant carcharhinid selachiens

Leder, Ronny Maik 04 February 2015 (has links) (PDF)
Die morphologische Variabilität dentaler Strukturen, bei Haien der Familie der Carcharhinidae, ist sowohl innerhalb als auch zwischen den Arten unzureichend erforscht. Ohne Kenntnis der artspezifischen Parameter ist eine genaue taxonomische Klassifizierung von fossilen Haien anhand der Zähne jedoch unmöglich. Die umfassende Analyse der dentalen Strukturen rezenter carcharhinider Haie nach artspezifischen Merkmalen wurde genutzt, um die Ergebnisse auf die nächsten fossilen Verwandten zu übertragen. Besonderes Augenmerk galt darüber hinaus dem morphologischen Vergleich fossiler Zähne westatlantischer und zentralasiatischer Herkunft. Es wurde ein morphometrisches Analyseverfahren entwickelt, dass entgegen bestehender Methoden, gänzlich auf manuelle Datengewinnung verzichtet. Für die neue Methode der automatisierten algorithmischen Morphometrie (AAM) wurden erstmals, anhand von 2340 Einzelzähnen von 112 Individuen aus 41 Arten rezenter Carcharhinidae, die wesentlichen artspezifischen Merkmalskomplexe definiert und in ein Analyseprogramm samt Datenbank übertragen. Die Einzeluntersuchung der einzelnen Spezies nach Gesichtspunkten ontogenetischer, sexueller bzw. mono-/dignather Heterodontie sowie intra- und interspezifischer Varianz der Zahnmorphologie zeigte, dass carcharhinide Haie allein mit Hilfe zahnmorphologischer Merkmale identifiziert werden können und diese Merkmale für systematische Zwecke geeignet sind. Der Erfolg der systematischen Zuordnung steht aber in direkter Abhängigkeit zur Zahnposition und zur betrachteten Spezies. Der Einfluss der Heterodontie auf die taxonomische Aussagekraft ist mitunter enorm, so dass die Eindeutigkeit der taxonomischen Klassifizierung stark begrenzt wird. Es existiert eine enorme Bandbreite an morphologischen Überschneidungen und Durchdringungen, sowohl innerhalb der Arten als auch art- bzw. gattungsübergreifend. Beim Vergleich allein anhand einzelner Zähne, sowohl fossiler als auch rezenter Herkunft, ist es in vielen Fällen nicht feststellbar, ob noch innerartliche Varianz oder bereits artliche Differenz vorliegt. Aus den Erkenntnissen der morphometrischen Analyse und deren Übertragung auf die fossilen Belege, ergab sich die Notwendigkeit, fossile Zähne carcharhinider Haie zukünftig, neben dem bestehenden deskriptiven Verfahren der Taxonomie, zusätzlich funktionsmorphologisch zu beurteilen. Dazu wurden erstmals sechs funktionsmorphologische Gruppen definiert, mit deren Hilfe vor allem ökologische Schlussfolgerungen bei der Bewertung fossiler Zähne möglich sind. / The morphological variability of dental structures within the different species as well as between the species of sharks belonging to the family of the Carcharhinidae is insufficient investigated. Without knowledge of the species specific parameter the precise taxonomic classification based on the teeth morphology of fossil sharks is kind of impossible. The comprehensive analysis of dental structures of extant carcharhinid sharks was used to transfer the results to their next extinct relatives. Special attention was focused on the comparison between fossil teeth of populations with westatlantic and centralasiatic origin. A morphometric analysis program was established, that is in contrast to traditional methods not based on manual data collection. With the new method of automatic algorithmic morphometry (AAM) the essential species specific attribut complexes were defined for the first time by using the morphological data of 2340 single tooth from 112 individuals from 41 species of extant carcharhinid sharks and transfered to an appropriate new analysis program including all datasets in one database. Individual studies for each single species in aspects like ontogenetic, sexual, mono- and dignatic heterodondity as well as intra- and interspecific variance in tooth morphology proved the possibility to identify carcharhinid sharks just by their teeth and that these attributes can be used for systematic purposes. The effectiveness of the systematic classification stands in direct dependence to tooth position and investigated species. The heterodondity influence for the taxonomic significance is quite high and limiting the taxonomic classification. An enormous bandwith in morphological overlapping and interpenetration is existing as well as within the species but also between species respectively across genus. The comparison based on single teeth with both fossil and extant origin, makes it in many cases impossible to differentiate between intraspecific variance and already existing specific difference. From the new insight to morphological differentiation based on the morphometric analysis (AAM) established in this work and the tranfer from this informations to fossil samples the need for different view to fossil teeth of carcharhinid sharks was obvious. Beside the traditional descriptive procedure of taxonomy a method based on functional morphology is need to better reassess fossil carcharhinid shark teeth. Therefor six functional morphological groups where defined for the first time especially for paleoecological conclusions in the assessment of fossil teeth.

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