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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.
161

Aplicação da microtomografia computadorizada para a análise morfométrica bi e tridimensional na avaliação da perda óssea experimental em ratos / Use of micro-computed tomography in two and three-dimensional morphometric analyses for experimental bone loss evaluation in rats

Patricia Garani Fernandes 04 June 2014 (has links)
Introdução: A histomorfometria do osso é um dos métodos padronizados que pode ser utilizado para quantificar a microestrutura do osso trabecular. Existem muitos meios de acesso para conseguir a visualização dos defeitos ósseos no caso de um acometimento de doença periodontal, por exemplo. A extensão e morfologia da perda óssea alveolar podem ser acessadas e examinadas após confecção de retalhos mucoperiosteais em cirurgias periodontais ou através de exames radiográficos. A partir de então, a tecnologia da micro- CT tornou-se padrão ouro para avaliação da arquitetura 3D do osso trabecular; exibindo como uma de suas principais vantagens sua habilidade em proporcionar resultados quantitativos com pouco ou nenhum preparo da amostra e sem a sua destruição. Metodologia: Foram utilizados 40 ratos machos: ratos normotensos (WK) e espontaneamente hipertensos (SHR) foram divididos em grupos com doença periodontal induzida por ligaduras (DP), e grupos controle, em que a DP não foi induzida (C). Cada um desses quatro grupos foram divididos em 2 subgrupos, de acordo com o período de eutanásia, que foi realizada no 10° e no 21° dia do experimento, desse modo cada grupo teve um n=5. Os animais do grupo DP receberam ligadura com fio de algodão ao redor do primeiro molar inferior. Após a eutanásia todas as hemimandíbulas dos animais tiveram seu tecido mole removido através de processos químico e biológico a fim de proporcionar uma peça histológica preparada adequadamente para ser escaneada no microtomógrafo. Para realização da análise microtomográfica foi utilizado um aparelho modelo 1172 da fabricante SkyScan®. As amostras foram verificadas nos três planos espaciais através dos softwares CTAN®, DATA VIEWER® e CTVOX® que também foram utilizados para a visualização tridimensional, análise qualitativa e quantitativa da anatomia externa e interna do osso alveolar. Resultados: Os resultados das medidas lineares foram aqueles extraídos de uma imagem bidimensional de uma fatia única escolhida por ser a mais representativa para detectar a perda óssea alveolar. Para a quantificação dos parâmetros volumétricos foi realizada a avaliação em dois pontos distintos: a área da região de furca do M1 mandibular e a área da região interproximal entre M1 e M2 da mandíbula. De todos os parâmetros avaliados e analisados os mais representativos para detectar a perda óssea alveolar neste modelo de estudo foram: Furca e JCE-COV (junção cemento-esmalte crista óssea vestibular) em 2D (medidas lineares) e a relação entre a superfície óssea e o volume ósseo; relação entre o volume ósseo e o volume total; porosidade e densidade mineral óssea nos parâmetros em 3D (medidas volumétricas). Conclusão: A metodologia empregada mostrou ser eficiente para a caracterização da perda óssea alveolar nos grupos controle e doença periodontal. A região escolhida e o método de análise tem influência no resultado. Assim medidas lineares e medidas volumétricas de uma mesma amostra podem apresentar porcentagens diferentes em relação à perda óssea. / Introduction: The histomorphometry of bone is one of the standard methods that can be used to quantify the microstructure of the trabecular bone. There are many ways to get access to the visualization of bone defects in the case of onset of periodontal disease, for example. The extent and morphology of alveolar bone loss may be accessed and examined after making mucoperiosteais flaps in periodontal or through radiographic examinations surgeries. Since then, the technology of micro - CT has become the gold standard for evaluation of the 3D architecture of trabecular bone; showing as one of its main advantages its ability to provide quantitative results without destruction and with little or no sample preparation. Methodos: Normotensive rats (WK) and spontaneously hypertensive (SHR) were divided into groups of ligature-induced periodontal disease (PD), and control groups (C), where PD is not induced. 40 rats were used and each of these four groups were divided into 2 subgroups according to the time of euthanasia , which was held on the 10th and 21st day of the experiment , thus each group had an n = 5 . The animals in the PD group received ligature with cotton thread around the first molar. After euthanasia, all animals had their mandibles soft tissue removed through chemical and biological processes to provide a suitably prepared for micro-ct analysis. In order to perform the micro-CT analysis, a model 1172 device manufacturer of SkyScan® was used. The samples were observed in the three spatial planes through the CTAN®, DATA VIEWER® and CTVOX® softwares which were also used for threedimensional visualization, qualitative and quantitative analysis of the external and internal anatomy of the alveolar bone. Results: The results of linear measurements were those extracted from a twodimensional image of a single slice chosen for being the most representative for detecting bone loss. For quantification of the volumetric parameters were assessed at two different points: the area of the furcation region of the mandibular M1 and interproximal area of the region between M1 and M2 of the jaw. Of all the most representative in detecting alveolar bone loss in this model of study parameters were evaluated and analyzed : Furcation and cementum-enamel junction to the buccal bone crest = 2D (linear measurements) and the relationship between the bone surface and bone volume ; ratio of bone volume to the total volume ; porosity and bone mineral density in 3D parameters ( volumetric measurements). Conclusion: The methodology was efficient for the characterization of alveolar bone loss in the periodontal disease groups. The region chosen and method of analysis have affected the outcome. Thus, linear and volumetric measurements of the same sample may have different percentages in relation to bone loss.
162

Dynamique de mise en place des avalanches de débris sur les flancs aériens des volcans insulaires : le cas de La Réunion / Transport dynamic of the volcanic debris avalanches : La Reunion Island

Perinotto, Hélène 11 December 2014 (has links)
Les avalanches de débris, qui résultent du démantèlement des flancs des édifices volcaniques et montagneux, sont des écoulements granulaires rapides et dangereux dont le monteur est la gravité et qui présentent des distances de transport extrêmement importantes. La dynamique de leur mise en place et leurs mécanismes de transport permettant cette très grande mobilité sont des phénomènes qui demeurent encore mal compris. De nombreux modèles existent pour expliquer la grande mobilité des avalanches de débris et incluent des processus basés sur la lubrification ou la fluidification de la masse granulaire mais également sur le phénomène de désintégration dynamique des éléments. Cependant la grande majorité des modèles proposés souffre du manque d’observations de terrain et de quantification de l’évolution des matériaux au cours de leur transport au sein de la masse granulaire. Afin d’identifier les principaux mécanismes de transport des avalanches de débris, nous proposons dans ce travail une étude de terrain détaillée de dépôts d’avalanches de débris volcaniques qui résultent du démantèlement d’un volcan bouclier océanique, le Piton des Neiges (île de La Réunion, océan Indien). L’approche est couplée à un examen morphométrique (dimension fractale et circularité), exoscopique et granulométrique des particules présentes dans les dépôts. Elle est complétée par l’examen de la fabrique des dépôts basée sur l’anisotropie de la susceptibilité magnétique (ASM). Les données obtenues nous permettent de mettre en évidence une évolution de la dynamique de transport et de mise en place des dépôts d’avalanches de débris depuis les zones sources jusqu’aux domaines de dépôt distaux. On montre également que la désintégration dynamique et le gonflement dispersif qui l’accompagne opèrent tout au long du transport et à toutes les échelles au-dessus d’une limite inférieure de broyage à 500 μm. En dessous de cette limite, la réduction granulométrique résulte uniquement de processus d’attrition par friction entre les particules. La grande mobilité des avalanches de débris pourrait ainsi être expliquée par l’effet combiné de la libération d’énergie élastique par la désintégration dynamique des particules > 500μm et par une réduction de la friction interne à la matrice liée aux interactions dispersives des particules fines (< 500 μm). L’ensemble des données permettent également de préciser les directions de transport et l’ampleur des avalanches de débris liées aux déstabilisations du massif du Piton des Neiges. / Debris avalanches, resulting from flank collapses that shape volcanic and mountainous edifices are rapidand dangerous gravity-driven granular flows that travel long run out distances. The dynamic and the transport mechanisms behind this high mobility remain poorly understood. The numerous models proposed to explain this high mobility include processes based on lubrication or fluidisation of the granular mass of the flow body, but also the dynamic disintegration of the transported particles. To date,all these proposed mechanisms lack observational support and quantification of the state of the particles of the granular mass during the transport. To identify the main transport mechanisms, we propose here detailed field studies of volcanic debris avalanches deposits resulting of flank-collapse events on an oceanic shield volcano, the Piton des Neiges (La Réunion Island, Indian Ocean). This study has been combined with morphometric (fractal dimension and circularity), exoscopic and grain-size analyses. Moreover, the fabric of the deposits has been investigated by with the characteristics of the anisotropy of the magnetic susceptibility (ASM). From these data we highlight a proximal to distal evolution of the debris avalanches transport and emplacement dynamics. We demonstrate that syn-transport dynamic disintegration continuously operates with the distance from the source down to a grinding limit of 500μm. Below this limit, the particle size reduction exclusively results from the attrition of the particles by frictional interactions. Thus, the exceptional mobility of debris avalanches may be explained by thecombined effect of elastic energy release during the dynamic disintegration of the larger clasts (> 500μm) and frictional reduction within the matrix due to the dispersive interactions between the finer particles (< 500 μm). All these data also allow to specify the transport direction and the approximate size of the debris avalanches related to the Piton des Neiges destabilisations.
163

Biosystematic studies in the family Cyperaceae / Biosystematic studies in the family Cyperaceae

KOŠNAR, Jan January 2013 (has links)
The thesis was focused on the microevolutionary mechanisms that contribute to morphological diversity in selected members of the sedge family (Cyperaceae). Natural hybridization, evidenced from both morphological characters and molecular markers, was revealed to be a potentially important source of diversification in the tropical spikerushes of Eleocharis subgenus Limnochloa. High levels of phenotypic plasticity of clonal growth but rare genetic (ecotypic) differentiation among contrasting morphotypes were found in the polymorphic species Carex nigra, which implied that taxonomic splitting of the species was unreasonable.
164

RELAÇÕES MORFOMÉTRICAS E POTENCIAL DE MANEJO DE Maclura tinctoria (L.) D. Don Ex. Steud EM FORMAÇÕES SECUNDÁRIAS NO NOROESTE DO RIO GRANDE DO SUL / MORPHOMETRIC RELATIONS AND MANAGEMENT POTENCIAL OF Maclura tinctoria (L.) D. Don ex. Steud IN SECONDARY FORMATIONS IN NORTHWEST RIO GRANDE DO SUL

Lanzarin, Karina 25 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to characterize Maclura tinctoria individuals in anthropic secondary formations, as their growth aspects in diameter and basal area, their morphometric relationships, spatial distribution and crown regularity. Also analyzing the behavior of individuals with more than one trunk, called multitrunks, and establish regression models to estimate basal area increment, crown diameter and height. For this, they were measured in two distinct areas in Porto Mauá, RS, diameter at breast height, total height, crown diameter and punctual density of each individual (using Bitterlich method). The morphometric indices were calculated based on data obtained from the field. The regularity of the crown was obtained by the coefficient of variation of the crown rays. For spatial analysis was calculated K Ripley function. The annual periodic increment in diameter (IPAd) and basal area (IPAg) were obtained by analysis of growth rings. In order to verify if these variables influence increments, Pearson correlation analysis was performed. It was developed mathematical equations, the stepwise method to estimate the increment in basal area, crown diameter and total height. The tendency of multitrunks individuals in relation to the single-stem for all variables was verified using analysis of covariance. The multitrunks trees in general show a similar tendency to the trees with a single stem. The studied species have moderate growth to fast, presenting therefore great potential for management. The spatial distribution indicated groupings to a higher range to 15 meters. Morphometric indices varied widely, demonstrating the plasticity of the species. As the variation in crown rays was extensive, featuring its irregularity. The morphometric variables, did not exert significant influence on the increment in diameter of Maclura tinctoria individuals. This indicates that the growth in diameter is statistically the same regardless of tree form. However, the degree of slenderness and comprehensiveness index correlated with the periodic increment in basal area. It was possible to define equations with good settings for height, crown diameter and increment in basal area of the species. All the elaborate equations had dbh as dependent variable, indicating the strong correlation of this variable with the other characteristics of trees Maclura tinctoria. / O objetivo do presente trabalho foi caracterizar indivíduos de Maclura tinctoria em formações secundárias antropizadas, quanto a seus aspectos de crescimento em diâmetro e área basal, suas relações morfométricas, distribuição espacial e regularidade da copa. Além de analisar o comportamento de indivíduos com mais de um fuste, denominados multitroncos, e ainda elaborar modelos de regressão para estimar o crescimento em área basal, diâmetro de copa e altura. Para isso, foram medidos, em duas áreas distintas em Porto Mauá, RS, o diâmetro à altura do peito, altura total, diâmetro de copa e densidade pontual (pelo método de Bitterlich) de cada indivíduo. Os índices morfométricos foram calculados com base nos dados obtidos à campo. A regularidade da copa foi obtida através do coeficiente de variação dos raios de copa. Para análise espacial calculou-se a função K de Ripley. O incremento periódico anual em diâmetro (IPAd) e em área basal (IPAg) foram obtidos por análise dos anéis de crescimento. A fim de verificar que variáveis influenciam nestes incrementos, foi realizada análise de correlação de Pearson. Elaborou-se equações matemáticas, pelo método stepwise, para estimar o incremento em área basal, diâmetro de copa e altura total. A tendência dos indivíduos multitroncos em relação aos com fuste único para todas as variáveis foi verificada utilizando análise de covariância. As árvores multitroncos no geral demonstram tendência semelhante às árvores com fuste único. A espécie estudada possui crescimento moderado à rápido, apresentando, portanto, grande potencial para manejo. A distribuição espacial indicou agrupamentos para uma escala superior a 15 metros. Os índices morfométricos variaram amplamente, demonstrando a plasticidade da espécie. Assim como a variação nos raios de copa foi ampla, caracterizando sua irregularidade. As variáveis morfométricas, não exerceram influência significativa no incremento em diâmetro dos indivíduos de Maclura tinctoria. O que indica que o crescimento em diâmetro é estatisticamente o mesmo, independente da forma da árvore. Contudo, o grau de esbeltez e índice de abrangência apresentaram correlação com o incremento periódico em área basal. Foi possível definir equações com bons ajustes para a altura, diâmetro de copa e incremento em área basal da espécie. Todas as equações elaboradas tiveram como variável dependente o DAP, indicando a forte correlação desta variável com as demais características das árvores de Maclura tinctoria.
165

Morfometria e qualidade da água em microbacias do município de Guaçuí-ES

Gomes, João Batista de Oliveira 28 February 2012 (has links)
Made available in DSpace on 2016-12-23T14:37:28Z (GMT). No. of bitstreams: 1 Joao Batista de Oliveira Gomes.pdf: 1678687 bytes, checksum: 22733271d2132b74b590d748fa1086ac (MD5) Previous issue date: 2012-02-28 / No cenário mundial, a água passou a se tornar progressivamente um recurso disputado, tanto pela sua disponibilidade quantitativa, quanto qualitativa, para os mais diferentes usos. O acesso à água de boa qualidade deve ser garantido a todos os habitantes do planeta como direito básico de todos os seres vivos. O objetivo do estudo foi avaliar a morfometria e a qualidade da água superficial em microbacias no município de Guaçuí, localizado no sul do Estado do Espírito Santo, na Região da Serra do Caparaó. Foram selecionadas 10 microbacias da bacia do Ribeirão de São Tiago. Para o mapeamento e análise morfométrica das microbacias, foram utilizadas Ferramentas de Sistema de Informações Geográficas (SIGs). Para validação dos mapas usou-se a medida Kappa. Avaliaram-se 16 parâmetros físico, químicos e biológicos para determinar a qualidade da água e compará-los com os limites permitidos pela legislação. As coletas aconteceram entre os meses de setembro/2010 a agosto/2011 nos períodos de chuva e estiagem. A análise morfométrica mostrou que a bacia não está sujeita a enchentes e que sua declividade influencia na qualidade da água. As amostras analisadas mostraram que os parâmetros Sólidos Suspensos nas bacias com área agrícola, pastagens, café, frutas e hortaliças (AG), 10% apresentam uso moderado de uso e Turbidez, nas bacias de uso misto, agricultura e vegetação nativa (MC) apresentam 20% com uso inadequado para a agricultura. Nas bacias mistas (MC), período das chuvas, os níveis de potássio ficaram acima do recomendado para agricultura. As análises mostraram que o parâmetro coliforme termotolerante está fora dos limites recomendados pelo Ministério da Saúde para consumo humano / Globally, the water has become an increasingly contested resource, both for its availability quantitative and qualitative, for the most different uses. Access to good water quality must be guaranteed to all inhabitants of the planet as a basic right of all living beings. The aim of this study was to evaluate the morphology and surface water quality in watersheds in the county Guaçuí, located in the southern state of Espírito Santo, in the region of Serra do Caparaó. It Was selected 10 watersheds of the basin of the Ribeirão São Tiago. For mapping and morphometric analysis of micro, tools were used Geographic Information System (GIS). For validation of the maps used to measure Kappa. Sixteen parameters were evaluated physical, chemical and biological agents to determine the water quality and compare them to the extent permitted by law. Sampling took place between the months of the September/2010 to august/2011 during the rainy and dry seasons. The morphometric analysis showed that the basin is not subject to flooding and that its slope influences on water quality. The samples showed that the parameters suspended solids in the basins to cropland, pasture, coffee, fruits and vegetables (AG), 10% has moderate use of use and Turbidity in the basin mixed-use, agriculture and native vegetation (MC) are 20% with inappropriate use for agriculture. Basins mixed (MC), the rainy season, potassium levels were above the recommended level for agriculture. Analyzes showed that thermotolerant coliform parameter is outside the limits recommended by the Ministry of Health for human consumption
166

Análise Morfométrica de Staphylococcus aureus Meticilina Resistentes Cultivados em Diferentes Concentrações de Cloreto de Sódio e Oxacilina / Morphometric Analysis of Methicillin Resistant Staphylococcus aureus Grow in Different Concentrations of Sodium Chloride and Oxacilin

OLIVEIRA, Ana Cláudia Alves de 15 April 2010 (has links)
Made available in DSpace on 2014-07-29T15:30:34Z (GMT). No. of bitstreams: 1 AnaClaudiaOliveira.pdf: 1839747 bytes, checksum: 682694e3fdf66bf0d190f094c4aaa106 (MD5) Previous issue date: 2010-04-15 / Methicillin-resistant Staphylococcus aureus (MRSA) has been one of the most prevalent microorganisms that cause hospitals infections worldwide. Several studies show that this microorganism is often found colonizing health professionals. MRSA can cause skin infections from the severe pneumonia, with high resistance to different antimicrobial agents. This study aimed to evaluate morphometric changes in MRSA isolated from the saliva of health professionals, through the use of different concentrations of oxacillin and sodium chloride. The identification of morphological changes was assessed by growing the isolates in the following concentrations of Sodium Chloride and oxacillin: 2&#956;g, 4&#956;g and 6&#956;g and 2%, 4%, 6% and 7.5% and using the means of computerized morphometry. This technique was tested by microscopic computed by employing the software Image J 1.38 (HIH USA). Statistical analysis was performed using the Sigma Stat, version 2.03, and the differences between the groups were compared using the nonparametric Kruskal-Wallis (p <0.05). The 20 MRSA analyzed showed no alterations. The present study showed that Sodium Chloride and oxacilin at concentrations did not alter the development and morphology of MRSA. / Staphylococcus aureus meticilina resistentes (MRSA) têm sido um dos microorganismos causadores de infecções mais prevalentes nos hospitais em todo mundo. Vários estudos demonstram que estes germes são frequentêmente encontrados colonizando profissionais de saúde. MRSA podem causar desde infecções cutâneas a pneumonias graves, apresentando um perfil multirresistente frente aos antimicrobianos. Este estudo teve como objetivo avaliar alterações morfométricas em MRSA isolados da saliva de profissionais de saúde, mediante o emprego de diferentes concentrações de cloreto de sódio e oxacilina. A identificação de alterações morfológicas foi avaliada por meio do cultivo dos isolados nas seguintes concentrações de Cloreto de Sódio e oxacilina: 2&#956;g, 4&#956;g e 6&#956;g e 2%, 4%, 6% e 7,5% e da utilização da técnica de morfometria computadorizada, mediante o emprego do software Image J 1.38 (HIH USA). A análise estatística foi realizada empregando o programa Sigma Stat, versão 2.03, e as diferenças entre os grupos foram comparadas usando o teste não paramétrico de Kruskal-Wallis, (p<0,05). Os 20 MRSA analisados não apresentaram alterações morfológicas. O presente estudo observou que o Cloreto de Sódio e a oxacilina nas concentrações testadas não alteram o desenvolvimento e a morfologia dos MRSA.
167

Towards a combined statistical shape and musculoskeletal modeling framework for pediatric shoulder joint / Vers un framework combinant la modélisation statistique de forme et la modélisation musculosquelettique pour l’articulation de l’épaule pédiatrique

Salhi, Asma 21 June 2019 (has links)
La paralysie obstétricale du plexus brachial (POPB) est une paralysie du membre supérieur qui survient à la naissance et peut entraîner une déformation de l'articulation et un fonctionnement anormal de l'épaule. Bien que le traitement de la POPB tente de restaurer la fonction de l'épaule, la pathomécanique sous-jacente n'est pas encore clairement comprise. Les modèles computationnels sont efficaces pour fournir de telles informations, mais il n'existe aucun modèle d'articulation de l'épaule pédiatrique pour comprendre la POPB. Ainsi, ce travail de recherche a pour but de construire un framework combinant les avancées dans les domaines de la modélisation statistique de forme (MSF) et de la modélisation musculo-squelettique multi-corps (MCM). Due à l’insuffisance des données dans la cohorte pédiatrique, ce cadre a été mis en place pour l'articulation de l'épaule adulte. Pour cela, la précision de la MSF a été illustrée en prédisant 1) la forme de l'omoplate pré-morbide, et 2) les régions d'insertion musculaire sur l'omoplate et l'humérus. Cette méthode a ensuite été intégrée aux modèles MCM pour l'épaule adulte pour souligner l’importance des modèles spécifique-patient pour l’usage clinique. Pour le second objectif de cette thèse, j'ai développé un modèle MCM pédiatrique du complexe articulaire de l'épaule en utilisant le logiciel OpenSim. Grâce aux approches de cinématique et dynamique inverse, le modèle a permis de déterminer les différences de dynamique articulaires entre le côté sain et le côté pathologique. Les travaux futurs seront axés sur l’extension du travail réalisé pour la population pédiatrique afin de comprendre la pathomécanique de POPB. / Obstetrician Brachial Plexus Palsy (OBPP) is a common birth injury in children leading to shoulder joint deformity and abnormal function. While the management of OBPP disorder focuses on restoring the shoulder joint function, the underlying pathomechanics is not clearly understood yet. Computational models are effective to provide such insights, however, there is no pediatric shoulder joint model to understand the OBPP disorder. Thus, the global aim of this research work was to build a computational framework combining the advances in statistical shape modeling (SSM) and multi-body musculoskeletal modeling (MSKM) domains. Due to a lack of sufficient data in the pediatric cohort, I first developed the framework for adult shoulder joint. For this, I illustrated the accuracy of SSM in predicting 1) missing part of the scapula, and 2) muscle insertion regions on scapula and humerus bones. This method was then integrated with adult shoulder MSKMs to show the differences between generic and subject specific constructs. For the second aim of this thesis, I developed a pediatric MSKM of the shoulder joint complex using OpenSim software. Pediatric MSKM represented scapulothoracic, sternoclavicular, acromioclavicular, and glenohumeral joints with 13 degrees of freedom, and actuated by 52 musculotendon actuators representing 14 shoulder muscles. Using inverse kinematics and inverse dynamics approaches, the model was used to determine the differences in joint kinematics, and joint dynamics between healthy and unhealthy side of a single OBPP subject. Future work is focused on completing the framework on pediatric population and understanding the pathomechanics of OBPP.
168

Možnosti ERT a GPR pro analýzu polygonálních kryogenních struktur / Using ERT and GPR in polygonal patterned ground analysis

Široký, Jakub January 2014 (has links)
Polygonal cryogenic structures cannot be investigated with conventional methods as they could be harmed during measurement. A real3D GPR and ERT non-destructive surveys were used to examine and prove applicability for topsoil covered ice-wedge pseudomorphs and coarse-grained sorted polygons (patterned ground). A list of processing tools and algorithm suitable for such environments was created and tested. The benefits of 3D measurements are illustrated on horizontal slices and pseudo3D visualisation of 3D Cube. Basic morphometry characteristics of both forms were collected. Abilities of geophysical imaging for advanced shape characterisations are discussed, too. The low-frequency measurements gave better results at both sites. Pseudomorphs, 2 wide and up to 6,5 long, were found penetrating depth bigger than 3,5 . Sorted polygons, 2,5 wide in diameter, were depicted locked by stony ring of width around 1 . Sorting depth extends up to 0,54 depth for sure, perhaps more.
169

Charcoal Kiln Detection from LiDAR-derived Digital Elevation Models Combining Morphometric Classification and Image Processing Techniques

Zutautas, Vaidutis January 2017 (has links)
This paper describes a unique method for the semi-automatic detection of historic charcoal production sites in LiDAR-derived digital elevation models. Intensified iron production in the early 17th century has remarkably influenced ways of how the land in Sweden was managed. Today, the abundance of charcoal kilns embedded in the landscape survives as cultural heritage monuments that testify about the scale forest management for charcoal production has contributed to the uprising iron manufacturing industry. An arbitrary selected study area (54 km2) south west of Gävle city served as an ideal testing ground, which is known to consist of already registered as well as unsurveyed charcoal kiln sites. The proposed approach encompasses combined morphometric classification methods being subjected to analytical image processing, where an image that represents refined terrain morphology was segmented and further followed by Hough Circle transfer function applied in seeking to detect circular shapes that represent charcoal kilns. Sites that have been identified manually and using the proposed method were only verified within an additionally established smaller validation area (6 km2). The resulting outcome accuracy was measured by calculating harmonic mean of precision and recall (F1-Score). Along with indication of previously undiscovered site locations, the proposed method showed relatively high score in recognising already registered sites after post-processing filtering. In spite of required continual fine-tuning, the described method can considerably facilitate mapping and overall management of cultural resources.
170

Étude des réseaux neuronaux et des mécanismes cognitifs impliqués dans les déficiences intellectuelles liées au chromosome X / Study of neuronal networks and cognitive mecanisms involved in X linked intellectual disability

Curie, Aurore 08 April 2011 (has links)
Grâce aux progrès de la génétique moléculaire qui ont permis d’identifier de nouveaux gènes de déficience intellectuelle liée à l’X, il nous a été possible de travailler sur des groupes homogènes de malades présentant une mutation dans le même gène. Nous avons d’une part, pu mettre en évidence un dysfonctionnement du circuit cérébello-thalamo-préfrontal grâce à une étude en IRM morphométrique réalisée chez des patients ayant une mutation dans le gène Rab-GDI. D’autre part, nous avons identifié un phénotype tout à fait spécifique lié aux mutations du gène ARX, tant clinique que neuropsychologique, et cinématique, associant une atteinte très particulière de la motricité distale des membres supérieurs et du langage. La préhension des patients est pathognomonique, avec une préférence pour la pince pouce-majeur, une difficulté accrue pour l’utilisation du bord cubital de la main, et un trouble de la pronosupination. Sur le plan neuroanatomique, il existe une diminution de volume des noyaux gris centraux et des épaisseurs corticales des régions contrôlant la motricité, bien corrélées au paramètres de cinématique. Enfin, nous avons exploré les stratégies de raisonnement des patients déficients intellectuels atteints du syndrome de l’X fragile, d’une mutation du gène ARX ou de trisomie 21 en élaborant un paradigme de raisonnement visuel analogique issu des matrices de Raven. Nous en avons établi la trajectoire développementale. Les stratégies utilisées par les patients (étude en eyetracking) sont différentes de celles des contrôles y compris de même âge mental, avec un défaut d’inhibition majeur, encore plus franc chez les patients X fragiles que ceux porteurs de trisomie 21 / Thanks to progress in molecular genetics, that allowed identification of new genes responsible for X linked intellectual disability, we studied on homogeneous groups of patients presenting with a mutation in one or the other gene. In the first section, we showed dysfunction of cerebello-thalamo-prefrontal networks, thanks to morphological MRI study performed on patients with a mutation in the Rab-GDI gene. In the second section, we highlighted a very specific phenotype related to ARX gene mutations, clinically, neuropsychologically, and kinematically, with a very peculiar impairment of upper limbs distal motricity, and language disorder. Patients hand-grip is pathognomonic, with a preference for the middle finger instead of the index for the grip of object, major impairment of fourth finger use, and lack of pronation movements. Neuroimaging study showed decreased volume of basal ganglia, and cortical thickness of motor regions, well correlated to kinematic parameters. In the third section, we explored reasoning strategies in three groups of patients with intellectual deficiency: fragile X, ARX mutated and Down syndrome patients and controls (both chronological and mental age-matched subjects). We notably elaborated a visual analogical reasoning paradigm, inspired from Raven’s matrices. We established a developmental trajectory of this paradigm. The strategy used by patients (eyetracking study) was different from the one used by controls, with a huge lack of inhibition, even greater for fragile X patients than for Down syndrome patients

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