Das bei der Sanierung von großen segmentalen Knochendefekten bestehende Risiko einer fremdkörperassoziierten Infektion soll durch die Integration eines Wirkstofffreisetzungssystems in ein bestehendes textiles Knochenimplantat gemindert werden. Durch Immobilisierung des Wirkstoffs in eine degradierbare Polymermatrix wird eine zeitlich verzögerte Freisetzung bewirkt. Als Wirkstofffreisetzungssystem wird die Kombination von Polylactid (PLA) bzw. Poly(Lactid-co-Glycolid) (PLGA) als Matrixpolymer mit dem Antibiotikum Gentamicin als Wirkstoff untersucht, welches durch Beschichtung der textilen Scaffolds mittels Dip-Coating eingebracht werden soll. Es stehen die drei Beschichtungsmethoden „Suspension“, „Emulsion“ und „Schichtaufbau“ zur Auswahl, die jeweils über eigene Parameter zur Beeinflussung des Freisetzungsprofils verfügen. Die Methode „Suspension“ und die damit verbundenen Einflussfaktoren Korngröße, Korngrößenverteilung sowie Masseanteil des Antibiotikums und Schichtdicke der aufgetragenen Polymerschicht wurde als die günstigste herausgearbeitet. Im Teil II dieser Arbeit wird diese soweit optimiert, dass nahezu über den gesamten geforderten Zeitraum die festgelegte notwendige Dosierung aufrechterhalten werden kann. Erste in vitro Versuche weisen auf eine gute Zellverträglichkeit sowie eine ausreichende mikrobielle Wirksamkeit hin. / To reduce the risk of infection in the treatment of long bone defects, a novel embroidered bone implant is to be provided with an antibiotic drug delivery system. Prolonged and controlled drug release can be achieved by coating the thread material with antibiotics incorporated in a degradable polymer matrix. The chosen drug delivery system is composed of polylactide acid (PLA) or poly(lactide-co-glycolide) acid (PLGA) as matrix polymer and the antibiotic gentamicin. It is integrated into the textile structure by dip-coating providing the three different methods suspension, emulsion and layered. Each method bears its appropriate parameters to influence the releasing profile. The suspension-method and its parameters grain size and grain size distribution as well as mass fraction of the antibiotic and the coating thickness could be proved as the most feasible. In part II of this essay the chosen coating set-up gets optimized so that a drug release nearly along the whole required term can be achieved. Preliminary in vitro studies show a good cell tolerance besides a sufficient microbial efficacy.

Seismic methods have been used in sedimentary environment for almost 80 years. During that time, exploration geophysicists have developed a number of techniques to handle specific aspects of working in sedimentary areas. This is not the case for studies in the hardrock environment, where significantly less time and money have been invested on seismic investigations. Therefore, there is still a need to develop the right techniques appropriate for working in hardrock environments. The research presented here, covers aspects of acquisition, processing and interpretation in hardrock environments. A cost-effective alternative for two-dimensional data acquisition is presented. Acquisition parameters are also discussed and recommendations for future work are given. The main effort of this thesis, however, was to find appropriate processing methods to address some of the different problems present in datasets acquired in the hardrock environment. Comparison of two computer programs for first arrival seismic tomography was performed in order to find the most suitable one for processing crooked line geometries. Three-dimensional pre-stack depth migration was also tested to find a detailed near-surface image. A processing method geared to enhance the signal-to-noise ratio was applied to the dataset with the lowest signal amplitudes to improve the quality of the stack. Finally, cross-dip analysis and corrections were performed on two of the three datasets included in this thesis. Cross-dip analysis was also applied as an interpretation tool to provide the information needed for estimation of the true dip of some of the reflectors related to geological structures. The results presented in this thesis indicate that cross-dip analysis and corrections are one of the most powerful tools for processing and interpretation in the presence of complex geology. Therefore, it is recommended to include this method as a standard step in the processing and interpretation sequence of data acquired in hardrock environments.

The study of deformation zones is of great geological interest since these zones can separate rocks with different characteristics. The geometry of these structures with depth is important for interpreting the geological history of an area. Paper I to III present 2D reflection seismic data over deformation zones targeting structures in the upper 3-4 km of the crust. These seismic profiles were acquired with a crooked-line recording geometry. 2D seismic processing assumes a straight recording geometry. Most seismic processing tools were developed for sub-horizontally layered structures. However, in the crystalline rocks in Scandinavia more complex structures with contrasting dip directions and folding are common. The crooked-line recording geometries have the benefit of sampling a 3D volume. This broader sampling can be used to gain knowledge about the true geometry of subsurface structures. Correlation with geological maps and other geophysical data along with seismic data modeling can be used to differentiate reflections from faults or fracture zones from other reflectivity, e.g. mafic bodies. Fault and fracture zones may have a large impedance contrast to surrounding rocks, while ductile shear zones usually do not. The ductile shear zones can instead be interpreted based on differing reflectivity patterns between domains and correlations with geology or magnetic maps. Paper IV presents 3D reflection seismic data from a quick-clay landslide site in southern Sweden. The area is located in a deformation zone and structures in unconsolidated sediments may have been influenced by faults in the bedrock. The main target layer is located at only 20 m depth, but good surface conditions during acquisition and careful processing enabled a clear seismic image of this shallow layer to be obtained.The research presented in this thesis provides increased knowledge about subsurface structures in four geologically important areas. The unconventional processing methods used are recommended to future researchers working with data from crooked-line recording geometries in crystalline environments. The imaging of shallow structures at the quick-clay landslide site shows that the 3D reflection seismic method can be used as a complement to other geophysical measurements for shallow landslide site investigations.

Transparent conducting oxide (TCOs) thin films, including non-stoichiometric tin doped indium oxide (ITO) and aluminium doped zinc oxide (AZO), have found considerable applications in various displays, solar cells, and electrochromic devices, due to their unique combination of high electrical conductivity and optical transparency. TCO thin films are normally fabricated by sputtering, thermal vapour deposition and sol-gel method. Among them, sol-gel processing, which was employed in this project, is no doubt the simplest and cheapest processing method, The main objectives of this project were to produce indium tin oxides (ITO) and zinc aluminium oxides (AZO) nanoparticles with controlled particle size and morphology and to fabricate TCO thin films with high optical transmittance and electrical conductivity. In this research, hydrothermal method was used to synthesise ITO and AZO nanoparticles. Tin oxides, zinc oxides, ITO and AZO particles with the particle size ranging from 10 nm to several micrometers and different morphologies were synthesised through controlling the starting salts, alkaline solvents and hydrothermal treatment conditions. ITO and AZO thin films were fabricated via sol-gel technique through dip coating method. The effects of the starting salts, alkaline solvents, surfactant additives and coating and calcination conditions on the formation of thin films were investigated. XRD, TEM, FEG-SEM, DSC-TGA, UV-Vis spectrometer and four-point probe resistance meter were used to characterise the crystallinity, particle size, morphology, optical transmittance and sheet resistance of the particles and thin films. Crack-free thin films with high optical transmittance (>80% at 550 nm) and low sheet resistances (2.11 kΩ for ITO and 26.4 kΩ for AZO) were obtained in optimised processing conditions.

Made available in DSpace on 2017-07-21T14:19:27Z (GMT). No. of bitstreams: 1 Elvis Canteri.pdf: 1285842 bytes, checksum: f2c5d9e754ae68692d585d59818e0e5f (MD5) Previous issue date: 2015-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nitrogen (N) is a nutrient that is directly related to the plants development and proper nitrogen fertilization can provide harvest in less time and increase productivity. The N have been handled incorrectly and often non-satisfactory supplied to the land. Proper management depends on constant monitoring of nutritional status that can be accomplished by predicting the leaf nitrogen content. This work aims to evaluate digital image processing algorithms, in order to establish a valid method to estimate the nutritional stress of N (nitrogen) on maize, and the feasibility of its implementation on mobile devices using photos sampled in the field under natural lighting environment. It was found that the thresholding process should use the HSV factor, more suitable under natural light if the sampling in the field was conducted between 11:15 am and 14:55. Among the algorithms we highlight the results of the DGCI (Dark Green Color Index) obtained from factor HSV (Hue, Saturation, Vibration), with significant correlation to leaf analysis of corn (R² = 0.92) and the adoption of NDVI (Normalized Difference Vegetation Index) obtained from the RGB histogram (Red, Green, Blue). This is the same method studied considering the FieldScout CM 1000 and GreenSeeker chlorophyll meters used in this research. No significant correlation among the readings was found when considering values from chlorophyll meters obtained in any moment of the day or from different light conditions. However, there is a positive correlation among the FieldScout CM 1000 and GreenSeeker, corresponding to sampling among 11h16m and 14h32m (R² = 0.75) and among 12h15m and 14h53m (R² = 0.92), as well is possible to estimate the IRC of maize based on the DGCI to V5 to V7 phenological stages directly at crop field using a mobile device. / O nitrogênio (N) é um nutriente que é diretamente relacionado ao desenvolvimento das plantas e a adubação nitrogenada adequada pode proporcionar a colheita em menor tempo e com aumento na produtividade. O N vêm sendo manejado incorretamente e frequentemente suprido de modo insatisfatório pelo solo. O manejo adequado depende do monitoramento constante do estado nutricional que pode ser realizado estimando-se o teor de N foliar. O objetivo principal deste trabalho visa qualificar a utilização de algoritmos de processamento digital de imagens, com a finalidade de estabelecer um método válido para estimar o estresse nutricional de N (nitrogênio) da cultura do milho, bem como a viabilidade de sua implementação em dispositivos móveis, utilizando fotos amostradas em ambiente de campo sob iluminação natural. Constatou-se que o processo de limiarização deve ter base no fator HSV, mais adequado sob iluminação natural se considerarmos a amostragem em ambiente de campo, compreendido entre as 11h15min e 14h55min. Dentre os algoritmos destacam-se os resultados do DGCI (Dark Green Color Index) obtido do fator HSV (Hue, Saturation, Vibration), com significativa correlação para análise foliar do milho (R²=0,92) e a adoção do NDVI (Normalized Difference Vegetation Index) obtido a partir do histograma RGB (Red, Green, Blue), sendo o mesmo método investigado com o uso dos clorofilômetros FieldScout CM 1000 e GreenSeeker, Não há correlação significativa entre as leituras efetuadas pelos clorofilômetros se forem consideradas leituras em qualquer momento do dia e sob diversas condições de luminosidade. Porém, há correlação positiva das leituras dos clorofilômetros FieldScout CM 1000 e GreenSeeker, correspondendo a amostragem entre as 11h16m e 14h32m (R²=0,75) e entre as 12h15m e 14h53m (R²=0,92), bem como torna-se possível estimar o IRC da cultura do milho com base no DGCI para o estádio fenológico V5 a V7 em ambiente de campo utilizando um dispositivo móvel.

Made available in DSpace on 2017-07-21T14:19:28Z (GMT). No. of bitstreams: 1 Teruo Matos.pdf: 2738201 bytes, checksum: 54ed354d6ee1a18f2c735e38746cafc8 (MD5) Previous issue date: 2016-09-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The study of roots is used to monitor and optimize the uptake of water and nutrients. The evaluation of the plant root system by traditional methods is slow, exhaustive, complex and in many cases does not provide the required accuracy. This research aimed to develop a computational method to assist in the assessing of the average diameter and length of root maize. It was developed using Java programming language, JavaCV interface, and OpenCV library, subsequently its accuracy was compared to the traditional methods and the macro IJ_Rhizo accuracy, for measuring the average diameter and length of roots. The tests were performed using images of maize roots with 300 dpi and using images of nylon threads with resolutions of 300 dpi and 600 dpi. The method validation was performed using nylon thread samples with known lengths and diameters. For length measurements, the proposed method obtained coefficients of variation from 0.05% to 3.80% and 0.06% to 9,27%, with 300 dpi and 600 dpi images, respectively. For diameter measurements, the proposed method obtained coefficients of variation from 0.23% to 77.49% and 0.54% to 96,61%, with 300 dpi and 600 dpi images, respectively. The proposed method obtained coefficients of variation lower than traditional methods for length and diameter measurements, and the macro IJ_Rhizo in more than 95% of test cases. Thus, the presented method is shown to be the most appropriate, and with greater accuracy for measurement of average diameter and length of root, among the assessed methods. / O estudo de raízes é usado para monitorar e otimizar a utilização de água e nutrientes pelas plantas. A avaliação do sistema radicular de plantas por meio dos métodos tradicionais é demorada, exaustiva, complexa e, em muitos casos, não fornece a acurácia necessária. Este trabalho teve como objetivo desenvolver um método computacional que auxiliasse na avaliação do diâmetro médio e comprimento radicular da cultura de milho. Ele foi desenvolvido utilizando a linguagem de programação Java, a interface JavaCV, e a biblioteca OpenCV, posteriormente a acurácia dele foi comparado a dos métodos tradicionais e a da macro IJ_Rhizo, para medição do comprimento e do diâmetro médio de raízes. Os testes foram realizados utilizando imagens de raízes de milho com 300 dpi e imagens de fios de náilon com 300 dpi e 600 dpi. A validação do método foi realizada utilizando amostras de fios de náilon com comprimento e diâmetros conhecidos. Para as medidas de comprimento, o método proposto obteve coeficientes de variação de 0,05% a 3,80% e de 0,06% a 9,27%, com imagens de 300 dpi e 600 dpi, respectivamente. Para as medidas de diâmetro, o método proposto obteve coeficientes de variação de 0,23% a 77,49% e de 0,54% a 96,61% , com imagens de 300 e 600 dpi, respectivamente. O método proposto obteve coeficientes de variação inferiores aos métodos tradicionais para a medição do comprimento e do diâmetro, e a macro IJ_Rhizo em mais de 95% dos casos de teste. Assim, o método apresentado mostra-se o mais adequado e o com maior acurácia para a medição do comprimento e diâmetro radicular médio dentre os métodos avaliados.

Submitted by Fabiano Malheiro (fabianomalheiro22@hotmail.com) on 2019-02-01T12:26:25Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Revestimentos biomiméticos para superfícies de titânio em aplicações biomédicas.pdf: 8421154 bytes, checksum: 3579eb98998151e0dbd81f5e4fb61cec (MD5) / Made available in DSpace on 2019-02-01T12:26:25Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Revestimentos biomiméticos para superfícies de titânio em aplicações biomédicas.pdf: 8421154 bytes, checksum: 3579eb98998151e0dbd81f5e4fb61cec (MD5) Previous issue date: 2017-08-09 / Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS / A osteointegração produto de próteses ósseas de titânio, continua sendo um ponto crítico e problemático recorrente no processo de reabilitação. Esforços para aperfeiçoar a resposta na interface "superfície-célula" dos implanto-materiais, têm sido direcionados para melhorar as propriedades físico-químicas das superfícies e induzir a adesão, proliferação, diferenciação ou apoptose celular. Revestimentos biomiméticos com superfícies sensíveis em titânio representam alternativas com resultados promissores para a resposta celular promovendo a formação de uma conexão funcional entre a superfície do material e o tecido ósseo. Para abordar esse tema foram realizados uma revisão sistemática relacionado ao tema e um estudo laboratorial para determinar as características de revestimentos de superfície biomiméticas (biomoléculas) em titânio e respostas celulares em relação à. No primeiro artigo foi realizada uma revisão sistemática para to avaliar a resposta celular produzida pelo tratamento de superfícies de titânio mediante o uso da técnica de polarização catódica.Treze estudos foram cumpriram com os critérios de inclusão e foram incluídos na revisão. Os resultados in vitro e in vivo relataram que o uso de polarização catódica promoveu superfícies com hidride e deposição efetiva e adesão das biomoléculas revestidas. O método eletroquímico, promoveu maior ou comparável viabilidade celular, proliferação, adesão, diferenciação ou crescimento ósseo. Para os artigos 2 e 3, foram desenvolvidos revestimentos de superfícies biomiméticas pelas técnicas de sol-gel dip-coating e polarização eletroquímica com diferentes configurações de superfícies estimulo responsivas multicamada e combinação de biomoléculas em titânio. O desenvolvimento das superfícies foi realizado e as amostras foram caracterizadas mediante microscopia de Força Atômica, Análise de Raios X de Energia Dispersa e citotoxicidade. A análise estatística foi descritiva e analítica (Stata 11.0). Os resultados foram submetidos a análise de variância ANOVA e/ou teste de Kruskall Wallis com nível de significância de 5% (p ≤ 0.05). No artigo 2, os resultados demonstraram que o grupo de superfícies modificadas com TiO2: Li+ (15%): Zr (15%)/PEG mediante o método sol-gel dip coating, promoveu maior crescimento celular (p>0,05) comparado ao resto dos grupos experimentais. No artigo 3, os resultados demonstraram que o grupo de superfícies modificadas com Indium tin oxide (In2O5Sn) mediante o método sol-gel dip coating, promoveu alto crescimento celular comparável estatisticamente ao grupo controle (p>0,05) e que o grupo que usou a técnica de polarização catódica promoveu crescimento celular. A polarização catódica promove alta viabilidade celular. In vitro, a técnica sol-gel e de polarização eletroquímica modificaram as superfícies de titânio. Entre as biomoléculas ativas, In2O5Sn e TiO2: Li+(15%):Zr(15%)/PEG aumentaram a viabilidade celular. / Osseointegration product of titanium bone prostheses continues to be a recurring and problematic point in the rehabilitation process. Efforts to improve the response in the interface "surface-cell" of implant-materials have been address to enhance physicochemical properties of the surfaces and induce cellular adhesion, proliferation, differentiation or apoptosis. Biomimetic coatings with titanium sensitive surfaces represent alternatives with promising results for the cellular response to osseointegration and can stimulate positive biological responses, promoting the formation of a functional connection between the surface of the material and the bone tissue, producing sufficient stimuli in the vascularization for the performance of tissue metabolic changes. To address this theme, a systematic review on the subject and a laboratory study were carried out to determine the characteristics of titanium biomimetic surface coatings (biomolecules) and the cellular responses. In the first article, a systematic review was carried out to evaluate the cellular response produced by the treatment of titanium surfaces using the cathodic polarization technique. Thirteen studies accomplished the inclusion criteria and were included in the review. In vitro and in vivo results reported that the use of cathodic polarization promoted surfaces with hydride and effective deposition and adhesion of the coated biomolecules. The electrochemical method promoted higher or comparable cellular viability, proliferation, adhesion, differentiation or bone growth than the group’s control. For articles 2 and 3, biomimetic surface coatings were developed by integrated dipcoating sol-gel techniques and electrochemical polarization with different configurations of multilayer responsive stimulus surfaces and combination of biomolecules in titanium. Surface development was performed and Atomic Force Microscopy, Dispersed Energy X-ray Analysis and cytotoxicity, characterized the samples. The statistical analysis was descriptive and analytical (Stata 11.0). The results were submitted to the analysis of variance ANOVA and/or Kruskal Wallis test to determine possible differences between the groups with a significance level of 5% (p ≤ 0.05). In article 2, the results showed that the group of modified surfaces with TiO2: Li + (15%): Zr (15%)/ PEG by the sol-gel dipcoating method, promoted higher cell growth (p> 0.05) than the rest of the experimental groups. In article 3, the results showed that the group of surfaces modified with Indium tin oxide (In2O5Sn) by the solgel dip coating method promoted high cell growth statistically comparable to the control group (p> 0.05) and the group that used the cathodic polarization technique promoted cell growth. Cathodic polarization promotes high cell viability and bone growth. In vitro, the sol-gel dip coating technique and electrochemical polarization modified titanium surfaces. Among the active biomolecules, In2O5Sn and TiO2: Li+ (15%): Zr (15%) / PEG increased cell viability.

No description available.

<p>Seismic methods have been used in sedimentary environment for almost 80 years. During that time, exploration geophysicists have developed a number of techniques to handle specific aspects of working in sedimentary areas. This is not the case for studies in the hardrock environment, where significantly less time and money have been invested on seismic investigations. Therefore, there is still a need to develop the right techniques appropriate for working in hardrock environments. The research presented here, covers aspects of acquisition, processing and interpretation in hardrock environments. A cost-effective alternative for two-dimensional data acquisition is presented. Acquisition parameters are also discussed and recommendations for future work are given. The main effort of this thesis, however, was to find appropriate processing methods to address some of the different problems present in datasets acquired in the hardrock environment. Comparison of two computer programs for first arrival seismic tomography was performed in order to find the most suitable one for processing crooked line geometries. Three-dimensional pre-stack depth migration was also tested to find a detailed near-surface image. A processing method geared to enhance the signal-to-noise ratio was applied to the dataset with the lowest signal amplitudes to improve the quality of the stack. Finally, cross-dip analysis and corrections were performed on two of the three datasets included in this thesis. Cross-dip analysis was also applied as an interpretation tool to provide the information needed for estimation of the true dip of some of the reflectors related to geological structures. The results presented in this thesis indicate that cross-dip analysis and corrections are one of the most powerful tools for processing and interpretation in the presence of complex geology. Therefore, it is recommended to include this method as a standard step in the processing and interpretation sequence of data acquired in hardrock environments. </p>

The objective of this study is to develop a robust portable nano-calorimeter sensor for detection of energetic materials, primarily explosives, combustible materials and propellants. A micro-cantilever sensor array is actuated thermally using bi-morph structure consisting of gold (Au: 400 nm) and silicon nitride (Si3N4: 600 nm) thin film layers of sub-micron thickness. An array of micro-heaters is integrated with the microcantilevers at their base. On electrically activating the micro-heaters at different actuation currents the microcantilevers undergo thermo-mechanical deformation, due to differential coefficient of thermal expansion. This deformation is tracked by monitoring the reflected ray from a laser illuminating the individual microcantilevers (i.e., using the optical lever principle). In the presence of explosive vapors, the change in bending response of microcantilever is affected by the induced thermal stresses arising from temperature changes due to adsorption and combustion reactions (catalyzed by the gold surface). A parametric study was performed for investigating the optimum values by varying the thickness and length in parallel with the heater power since the sensor sensitivity is enhanced by the optimum geometry as well as operating conditions for the sensor (e.g., temperature distribution within the microcantilever, power supply, concentration of the analyte, etc.). Also, for the geometry present in this study the nano-coatings of high thermal conductivity materials (e.g., Carbon Nanotubes: CNTs) over the microcantilever surface enables maximizing the thermally induced stress, which results in the enhancement of sensor sensitivity. For this purpose, CNTs are synthesized by post-growth method over the metal (e.g., Palladium Chloride: PdCl2) catalyst arrays pre-deposited by Dip-Pen Nanolithography (DPN) technique. The threshold current for differential actuation of the microcantilevers is correlated with the catalytic activity of a particular explosive (combustible vapor) over the metal (Au) catalysts and the corresponding vapor pressure. Numerical modeling is also explored to study the variation of temperature, species concentration and deflection of individual microcantilevers as a function of actuation current. Joule-heating in the resistive heating elements was coupled with the gaseous combustion at the heated surface to obtain the temperature profile and therefore the deflection of a microcantilever by calculating the thermally induced stress and strain relationship. The sensitivity of the threshold current of the sensor that is used for the specific detection and identification of individual explosives samples - is predicted to depend on the chemical kinetics and the vapor pressure. The simulation results showed similar trends with the experimental results for monitoring the bending response of the microcantilever sensors to explosive vapors (e.g., Acetone and 2-Propanol) as a function of the actuation current.