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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

The implications of small size in Teleost fish, with special reference to the Gobioidei

Harrison, I. J. January 1987 (has links)
No description available.
2

Morphometry of human lung with physiological correlations

McLean, Alexander January 1987 (has links)
Resected lobes from patients having pre-operative pulmonary function tests were fixed by inflation with formal saline and cut into 1cm parasagittal slices. Randomly selected tissue, from the lateral two slices, was plastic embedded and sections prepared for microscopic analysis. A semi-automatic image analysis system was used to quantitate bronchiolar calibre and shape and peribronchiolar attachment number, inter-alveolar attachment distance and the amount of macroscopic emphysema. An automatic image analyser (IBAS2) was used to measure alveolar surface area per-unit volume (AWUV). Measured bronchiolar calibre (minimum diameter and measured lumen area) was not related to patient height, lung volume, pulmonary function or other morphometric variables. AWUV, mean inter-alveolar attachment distance, theoretical lumen area and bronchiolar shape were independent of patient size and lung volume, but were inter-related. A combination of low AWUV and loss of attachments profoundly affected bronchiolar shape. However, AWUV and alveolar attachment loss were not always in proportion and demonstrated different functional effects: AWUV affects carbon monoxide transfer factor whereas attachments affect the slope of phase III and forced expiratory volume with bronchiolar shape affecting closing volume. Macroscopic emphysema did not accurately reflect the extent of alveolar wall loss as identified by AWUV and showed poor correlations with pulmonary function tests. Computerised axial tomography (CT scan) exhibited a strong correlation with AWUV and can be used to assess lung density in life.
3

Gray matter volume differences of adult migraine patients using voxel-based morphometry

Escobar, Andrea 08 April 2016 (has links)
BACKGROUND: Migraine is a primary headache disorder that has a high prevalence and burden of disease throughout the world. Migraine symptoms include throbbing head pain, nausea, hypersensitivity to light, sound, and smell, and autonomic, cognitive, emotional, and motor disturbances. About a third of migraineurs have aura symptoms which are transient neurological symptoms with gradual onset before the migraine attack, visual disturbances, sensory loss, and/or communication impairment. The trigeminovascular system, central descending modulation, and brainstem descending modulation have been implicated in the pathophysiology of migraine. However, the exact neurovascular mechanism for migraine has not been determined. Several imaging techniques have been used to find structural and functional brain changes in migraineurs. OBJECTIVE: In order to further existing knowledge of migraine pathophysiology, structural brain differences were investigated using imaging between migraineurs and healthy individuals and differences within migraineurs. METHODS: Thirty-two patients with migraine (25 females) and 32 healthy control subjects (25 females) age-, ethnicity-, and gender-matched participated in our study. Magnetic resonance imaging (MRI) scans were collected from each participant. Then, voxel-based morphometry (VBM) was utilized to find any gray matter (GM) volume differences between migraine patients and controls. Also, VBM was performed in specific regions-of-interest (ROIs) to compare 11 migraine patients with aura (MA) and 11 migraine patients without aura (MO). RESULTS: A significant increase in regional gray matter volume difference was observed for migraine patients compared to control subjects in the intracalcarine gyrus of the visual cortex (corrected, p<0.05). In the VBM analysis of ROIs, the similarities between the MO and MA subjects included increases in the anterior cingulate cortex (ACC), hippocampus, insula, and intracalcarine cortex, along with decreases in the ACC and insula (uncorrected, p<0.05). MO subjects had decreases in the amygdala, hippocampus, intracalcarine cortex, and thalamus, but not in the MA subjects (uncorrected, p<0.05). The MA patients had increases in the amygdala and thalamus, but not in the MO patients (uncorrected, p<0.05). DISCUSSION: It can be concluded that the visual cortex is involved in the migraine mechanism since a large increase in GM volume difference was found in migraine, MO, and MA cohorts, as well as results from previous studies. Numerous GM volume changes in MO and MA cohorts reinforce evidence that particular brain regions are a part of migraine pathophysiology, but there were some regions that do not. Further research using imaging analysis and with larger study populations should be conducted to enhance our understanding of the migraine mechanism and differences that arise between migraine groups, so that diagnosis and treatment administration can be improved.
4

Morfometria da bacia hidrográfica do rio Bobo no Estado de Nariño, Colômbia /

Benavides Mora, Victória. January 2008 (has links)
Orientadora: Teresa Cristina Tarlé Pissara / Banca: Jairo Augusto Campos de Araújo / Banca: Sérgio Campos / Resumo: O objetivo deste trabalho foi caracterizar morfometricamente a bacia hidrográfica do rio Bobo, Estado de Nariño, Colômbia. A partir de cartas topográficas da área, na escala 1:25.000, foi gerado um mapa base da rede de drenagem e dos limites das microbacias de 2a ordem de magnitude. As características morfométricas dimensionais, do padrão da rede de drenagem e do relevo foram determinadas para o estudo do comportamento hidrológico da bacia. A bacia hidrográfica do Rio Bobo apresenta extensão superficial de 224,97 km2 e perímetro de 71,31km, sendo considerada de 6a ordem de magnitude. Ela é formada por 176 canais de 2a, 34 de 3a, 9 de 4a e 3 de 5a ordem de magnitude. Apresenta densidade de drenagem média de 3,71 km/km², que reflete a alta densidade, com conformação bastante forte e dissecada. A região caracteriza-se por apresentar um padrão de uso típico das zonas andinas, com bosque nativo e predomínio de culturas temporárias de batata e hortaliças tradicionais. / Abstract: The objective of this work was to realize the morphometric characterization of the Bobo river watershed, Nariño State, Colombia. From topographical maps, scale 1:25.000, was created a map using as database the drainage net and the limit of each 2nd order microbasin. The dimensional, drainage net and relief morphometric parameters were evaluated for a previous hydrological study. The drainage area was 224.97 km2 and 71.31 km of perimeter. The Bobo river watershed is considered as 6th order of magnitude, and has 176 drainage channel of 2sd order of magnitude; 34 drainage channel of 3rd order of magnitude; 9 drainage channel of 4th order of magnitude; 3 drainage channel of 5th order of magnitude. The average drainage density is 3.71km/km², which reflect the high density, with a string and dissecated geological formation. The area shows an andine land use, with native vegetation and productive system with potato. / Mestre
5

Alterações testiculaes no diabetes aloxânico no rato: estudo morfométrico e ultraestrutural dos túbulos seminíferos

Trindade, Amélia Arcângela Teixeira [UNESP] 07 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-07Bitstream added on 2014-06-13T18:40:27Z : No. of bitstreams: 1 trindade_aat_dr_botfm.pdf: 5590316 bytes, checksum: fb69498bced2d623453a9f1aec19253e (MD5) / Universidade Estadual Paulista (UNESP) / Este estudo foi realizado com o objetivo de avaliar, no longo prazo, os parâmetros morfométricos e ultraestruturais dos tubulos seminíferos dos testículos de ratos diabéticos aloxânicos. 60 ratos Wistar, machos, pesando de 250 a 280 gramas foram divididos em 2 grupos experimentais: N ou grupo normal, constituído de 30 animais sadios, nãodaibéticos; D ou grupo diabético, constituído de 30 animais diabéticos sem qualquer tratamento da doença. Cada grupo experimental foi posteriormente dividido, por sorteio, em 3 subgrupos de ratos, com 10 animais cada um, para serem avaliados e sacrificados com 1, 6 e 12 meses de seguimento. O diabetes experimental foi induzido pela administração endovenosa de aloxana 2%, na dose de 42 mg/kg de peso corporal. Somente animais com sinais clínicos evidentes de diabetes grave e com glicemia >250 mg/dl e glicose urinária > 3000 mg/dl foram utilizados neste experimento. Com 1, 6 e 12 meses de seguimento o peso corporal, a ingestão hídrica, a ingestão alimentar, a diurese e os níveis de glicose sanguínea foram avaliados em todos os animais. Com 1 e 6 meses de seguimento também foram analisados os níveis de insulina plasmática, hemoglobina glicosilada (HbA1C) e de testosterona sérica Após os sacrifício dos animais, ambos os testículos foram removidos, sendo o testículo esquerdo preparado para a microscopia ótica e o direito para a microscopia eletrônica. As medidas morfométricas à M.O. e M.E. foram realizadas por análise digital de imagens utilizando o software Quin Lite 2.5 - LEICA . A ultraestrutura dos túbulos seminíferos foi analisada ao microscópio de transmissão PHILIPS, pela análise descritiva comparativa. Neste experimento foram analisados os seguintes parâmetros: a) área total dos túbulos seminíferos; b) espessura do epitélio tubular; c) área do lúmen tubular; d) espessura do epitélio germinativo; e) porcentagem... / This study was conducted to evaluate, in the long term, ultrastructural and morphometric parameters of seminiferous tubules of the testis of diabetic rats alloxan. 60 male Wistar rats weighing 250-280 grams were divided into two groups: group N or normal, consisting of 30 healthy animals, non-daibetics; D or diabetic group, consisting of 30 diabetic animals without in treatment. Each experimental group was then divided in three subgroups of rats with 10 animals each to be evaluated and sacrificed at 1, 6 and 12 months of follow-up. Experimental diabetes was induced by intravenous administration of alloxan 2% at a dose of 42 mg / kg body weight. Only animals with obvious signs of severe diabetes and blood glucose> 250 mg / dl and urine glucose> 3000 mg / dl were used in this experiment. At 1, 6 and 12 months of follow-up body weight, water intake, food intake, diuresis and blood glucose levels were evaluated in all animals. At 1 and 6 months of follow-up were also analyzed the levels of plasma insulin, glycosylated hemoglobin (HbA1C) and serum testosterone after the animal sacrifice, both testis were removed, the left was prepared for light microscopy and the right to the electron microscopy. Morphometric measures at M.Ö. and ME were performed by using digital image analysis software Quin Lite 2.5 - LEICA. The ultrastructure of the seminiferous tubules was analyzed by transmission microscope PHILIPS, by comparative descriptive analysis. In this experiment we analyzed the following parameters: a) total area of seminiferous tubules, b) epithelium area, c) lumen area, d) thickness of the germinal epithelium, e) percentage of tubular lumen or proportion of lumen area in relation to the total area, f) percentage of epithelium or proportion of epithelium area in relation to the total area; g) number of tubules per mm2. The results of clinical and laboratory parameters... (Complete abstract click electronic access below)
6

A Study of Plankton Dilution in Source Streams Compared with that of Lake Dallas Proper

Evans, Archibald A. 08 1900 (has links)
This study was a comparative study of Plankton of Lake Dallas and the three main source streams. Based on the analysis of data, which was presented relative to the organisms taken from the lake and from the source streams, the results obtained are discussed, the Plankton seem to be largely autogenetic in Lake Dallas, the source streams Elm Fork and Clear Creek form a dilution process.
7

Alzheimer's disease heterogeneity assessment using high dimensional clustering techniques

Poulakis, Konstantinos January 2016 (has links)
This thesis sets out to investigate the Alzheimer's disease (AD) heterogeneity in an unsupervised framework. Different subtypes of AD were identified in the past from a number of studies. The major objective of the thesis is to apply clustering methods that are specialized in coping with high dimensional data sets, in a sample of AD patients. The evaluation of these clustering methods and the interpretation of the clustered groups from a statistical and a medical point of view, are some of the additional objectives. The data consist of 271 MRI images of AD patients from the AddNeuroMed and the ADNI cohorts. The raw MRI's have been preprocessed with the software Freesurfer and 82 cortical and subcortical volumes have been extracted for the needs of the analysis. The effect of different strategies in the initialization of a modified Gaussian Mixed Model (GMM) (Bouveyron et al, 2007) has been studied. Additionally, the GMM and a Bayesian clustering method proposed by Nia (2009) have been compared with respect to their performances in various distance based evaluation criteria. The later method resulted in the most compact and isolated clusters. The optimal numbers of clusters was evaluated with the Hopkins statistic and 6 clusters were decided while 2 observations formed an outlier cluster. Different patterns of atrophy were discovered in the 6 clusters. One cluster presented atrophy in the medial temporal area only (n=37,~13.65%). Another cluster resented atrophy in the lateral and medial temporal lobe and parts of the parietal lobe (n=39,~14.4%). A third cluster presented atrophy in temporoparietal areas but also in the frontal lobe (n=74,~27.3%). The remaining three clusters presented diffuse atrophy in nearly all the association cortices with some variation in the patterns (n1=40,~14.7%,n2=58,~21.4,n3=21,7.7%). The 6 subtypes also differed in their demographical, clinical and pathological features.
8

Mechanisms and consequences of nutritional depletion in early lung cancer

Jagoe, Robert Thomas January 2000 (has links)
No description available.
9

Morfometría de especies de Aphididae (Hemiptera) procedentes de Cieneguilla (Lima-Perú)

Torres Carrasco, Sara Virginia Olinda January 2015 (has links)
Se estudiaron dos poblaciones diferentes de áfidos en el distrito de Cieneguilla específicamente para la zona de Sierra Morena y Villa Toledo con un total de 282 ejemplares de áfidos: 13 alados, 254 ápteros y 15 ninfas. Reportando 11 nuevas especies de áfidos dentro de 12 hospederos de importancia agrícola, medicinal y económica. Estas especies fueron: Aphis craccivora (Koch, 1854), Aphis fabae (Scopoli, 1763), Aphis gossypii (Glover, 1877), Aphis spiraecola (Patch, 1914), Brachycaudus helichrysi (Kaltenbach, 1843), Macrosiphoniella sanborni (Gillette, 1908), Macrosiphum euphorbiae (Thomas, 1878), Myzus hemerocallis (Takahashi, 1921), Rhopalosiphum maidis (Fitch, 1856), Rhopalosiphum padi (Linnaeus, 1758), Toxoptera aurantii (Boyer de Fonscolombe, 1841) para la zona de Sierra Morena y Aphis craccivora (Koch, 1854), Aphis gossypii (Glover, 1877), Aphis spiraecola (Patch, 1914), Brachycaudus helichrysi (Kaltenbach, 1843), Myzus hemerocallis (Takahashi, 1921) para la zona de Villa Toledo. Por primera vez se realizaron mediciones indicando 13 variables diferentes encontrando a Macrosiphum euphorbiae (Thomas, 1878) como la especie que presenta mayor tamaño y Rhopalosiphum maidis (Fitch, 1856) la especie más pequeña. Two different populations of aphids were studied in the distric of Cieneguilla, especially in the area of Sierra Morena and Villa Toledo; this lead to a total of 282 of aphids: 13 winged 254 wingless and 15 nymphs. 11 new aphid species were reported within 12 hosts of agricultural, medical and economic importance. These species were: Aphis craccivora (Koch, 1854), Aphis fabae (Scopoli, 1763), Aphis gossypii (Glover, 1877), Aphis spiraecola (Patch, 1914), Brachycaudus helichrysi (Kaltenbach, 1843), Macrosiphoniella sanborni (Gillette, 1908 ), Macrosiphum euphorbiae (Thomas, 1878), Myzus hemerocallis (Takahashi, 1921), Rhopalosiphum maidis (Fitch, 1856), Rhopalosiphum padi (Linnaeus, 1758), Toxoptera aurantii (Boyer de Fonscolombe, 1841) for the area of Sierra Morena and Aphis craccivora (Koch, 1854), Aphis gossypii (Glover, 1877), Aphis spiraecola (Patch, 1914), Brachycaudus helichrysi (Kaltenbach, 1843), Myzus hemerocallis (Takahashi, 1921) for the area of Villa Toledo. Measurements were conducted for the first time where 13 different variables were stated and a Macrosiphum euphorbiae (Thomas, 1878) was found as the largest specie and Rhopalosiphum maidis (Fitch, 1856) as the smallest.
10

Estudo exploratório sobre biometria e estimativa de peso vivo de jumentos da raça Pêga / Exploratory study on biometrics and body weight estimation of Pêga breed donkeys

Moreira, Camilla Garcia 17 November 2016 (has links)
O jumento Pêga é uma raça nacional criada principalmente para a produção de muares marchadores, e possui valor econômico em todo território nacional. Com o objetivo de avaliar as medidas e índices morfométricos, eficácia de métodos de estimativa de peso vivo, bem como desenvolver uma fita de pesagem para jumentos da raça Pêga, foram utilizados 47 animais, 22 jumentas adultas e 25 jumentos em crescimento de ambos os sexos. As medidas morfométricas (peso fita; altura cernelha e garupa; distância codilho-solo; comprimento do corpo, cabeça, pescoço, espádua, dorso-lombo, garupa, antebraço e canela; perímetro torácico, de antebraço, canela e joelho; largura de cabeça, peito e anca) foram realizadas mensalmente com os animais posicionados em estação forçada em piso de concreto sem irregularidades ou inclinações. Após as mensurações, índices morfométricos foram calculados: índice dáctilo-torácico (IDT), de carga de canela (ICC), de conformação (ICF) e peso vivo verdadeiro (PVV). Para os jumentos em crescimento, equações lineares e não lineares descritas na literatura foram utilizadas para verificar sua aplicabilidade na fase de vida e espécie e desenvolveu-se uma equação para predição de peso com base na medida do perímetro torácico. Foi observado efeito do tempo de avaliação (P&lt;0,001) e não houve efeito de sexo (P&gt;0,05) para as medidas e índices morfométricos dos jumentos em crescimento. Os jumentos nascem com cerca de 14,86% do peso e 67,77% da altura das mães e aos seis meses atingem cerca de 40,37% do peso e 84,45% da altura. De acordo com a avaliação dos índices morfométricos, os jumentos adultos e em crescimento da raça Pêga são classificados como adaptados tanto à atividade de sela como tração, e que possuem maior capacidade de carga em relação aos equinos. Ao se comparar os métodos de pesagem, observou-se diferença (P&lt;0,001) entre os pesos da balança eletrônica e fita de pesagem comercial para equinos, sendo que a fita subestima o peso dos animais em crescimento, sendo necessário correção deste em 1,76%. As equações não lineares e as lineares encontradas na literatura, elaboradas para equinos e outras raças de jumentos não se adequam aos animais da raça Pêga do nascimento aos seis meses de idade, portanto sugere-se a utilização da equação desenvolvida no presente estudo (PV(kg)= -156,43+2,5178*PT), que apresenta coeficiente de determinação (R2) de 0,9638 com o peso vivo dos animais em crescimento. A partir da equação desenvolvida no presente estudo pode ser possível a elaboração de uma fita métrica para pesagem dos jumentos da raça Pêga em crescimento, o que tornaria o acompanhamento do crescimento dos animais mais prático e confiável. / The Pêga donkey is a national breed created mainly for the mules production, and has economic value throughout the national territory. In order to evaluate the measures and morphometric indexes, efficacy of live weight estimation methods, as well as to develop a weighing tape for Pêga donkeys, 47 animals were used, 22 adult donkeys and 25 growing donkeys of both sexes. The morphometric measures (weight tape, withers heigh, croup height, ground-to-ground distance, body length, head length, neck length, shoulder bone length, back-loin length, croup length, forearm length, shin length, thoracic perimeter, forearm perimeter, cinnamon perimeter, knee perimeter, head width, chest width and hip width) were performed monthly with the animals positioned at a forced station on a concrete floor without irregularities or slopes. After the measurements, morphometric indexes were calculated: dactyl-thoracic index (DTI), weigh in cannon index (WCI), conformation index (CI) and true live weight (TLW). For growing donkeys, linear and non-linear equations described in the literature were used to verify their applicability in the life stage and species, and an equation for weight prediction was developed based on the measurement of the thoracic perimeter. The effect of the evaluation time (P&lt;0.001) was observed and there was no effect of sex (P&gt;0.05) on morphometric measures and indexes of growing donkeys. The donkeys are born with about 14.86% of the weight and 67.77% of the height of the mothers and at six months they reach about 40.37% of the weight and 84.45% of the height. According to the evaluation of the morphometric indexes, adult and growing Pêga donkeys are classified as adapted to both saddle and traction activities, and have a higher carrying capacity in relation to equines. When comparing the weighing methods, we observed a difference (P&lt;0.001) between the weights of the electronic scale and commercial weighing tape for equines, and the tape underestimates the weight of the growing animals, which needs to be corrected in 1, 76%. The nonlinear and linear equations found in the literature, elaborated for equines and other donkey races, are not suitable for the Pêga breed from birth to six months of age, so it is suggested to use the equation developed in the present study (PV Kg) = -156.43 + 2.5178 * PT), which presents coefficient of determination (R2) of 0.9638 with live weight of growing animals. From the equation developed in the present study it may be possible to create a measuring tape for weighing the growing Pêga donkeys, which would make monitoring the growth of the animals more practical and reliable.

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