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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

New geophysical parameters for understanding the evolution of the St. Elias Orogen, southern Alaska

Worthington, Lindsay Lowe 25 February 2013 (has links)
The St. Elias Orogen is the result of oblique collision and flat-slab subduction in the Gulf of Alaska between North America (NA) and the Yakutat microplate (YAK). Extensive glaciation and a complex tectonic environment make this region a unique case study in which to examine the details of terrane accretion and the possible coupled influence of climate and tectonic drivers on the structural and topographic evolution of an orogenic wedge. The dataset for this project includes: 3 multi-channel seismic reflection surveys (~4000 km total seismic reflection data) and a ~450 km-long wide-angle seismic refraction profile. Reflection seismic profiles across the offshore YAK-NA deformation front, provide constraints for quantifying Pleistocene deformation recorded in the glaciomarine Yakataga formation. Growth strata and kinematic fold analysis allow comparison of relative timing of fault activity, which reveals temporal and spatial shifting of deformation within the margin towards the onshore eastern corner of the orogen. This information is important not only for the development of regional tectonic models, but also for understanding how climatic shifts may have affected the evolution of margin architecture during Pleistocene glacial-interglacial periods. Joint tomographic inversion of coincident reflection and refraction profiles constrains YAK crustal velocity and thickness. The offshore YAK crust ranges in thickness from 15 to 35 km, considerably thicker than normal oceanic crust. The crustal thickness and velocity structure support an oceanic plateau origin for the YAK microplate. Crustal velocity and structure are continuous across the YAK shelf except for a regional dip of the top of YAK crust of ~3° to the west. Moho arrivals across the profile do not mimic the dipping trajectory of the basement, indicating that the offshore YAK crust is doorstop-shaped, thinning in the convergence direction. This geometry leads to the following implications for the YAK-NA collision: first, uplift and deformation have intensified through time as successively thicker, more buoyant YAK crust attempts to subduct; second, current topography, exhumation and deformation patterns are partially controlled by underlying crustal geometry of converging YAK crust. / text
2

Mapping the Rivera and Cocos subduction zone

Suhardja, Sandy Kurniawan 11 March 2014 (has links)
The crust and upper mantle seismic structure beneath southwestern Mexico was investigated using several techniques including teleseismic tomography using 3D raytracing, a joint tomographic inversion of teleseismic and regional data that included relocation of regional seismicity, and a P to S converted wave study. The data used in these studies came from a broadband seismic deployment called MARS. The seismic deployment lasted 1.5 years from January 2006 to June 2007 and the stations covered much of Jalisco and Colima states as well as the western part of Michoacan states. At depth less than 50 km, P-wave receiver function images show a clear dipping slow velocity anomaly above a fast velocity layer. The slow anomaly convertor seen in receiver functions is directly above a fast dipping seismic anomaly seen in regional tomography results. The slow velocity with high Vp/Vs ratio is interpreted as a high pore fluid pressure zone within the upper layer of subducting oceanic crust. Regional seismicity was located using the double difference technique and then relocated in a tomography inversion. The seismicity is located very close to the slow dipping boundary to depths of 30-35 km and thus along the plate interface between the subducted and overlying plate. Deeper events are below the slow layer and thus are intraplate. Receiver function results also show a weaker continental Moho signal above the dipping slab that I interpret as a region of mantle serpentinization in the mantle wedge. Inland of the subduction zone, a clear Moho is observed with a maximum thickness of near 42 km although it thins to near 36 km depth towards the north approaching the Tepic-Zacoalco Rift. Using H-K analysis to examine Vp/Vs ratios in the crust, I find a band of very high Vp/Vs along the Jalisco Volcanic lineament as well as beneath the Michoacan-Guanajuato volcanic field. These observations suggest the continental crust is warm and possibly partially molten over broad areas associated with these two magmatic regions and not just locally beneath the volcanoes. I also found seismicity associated with the Jalisco Volcanic Lineament but it was trenchward of the volcanoes. This may indicate extension in this region is part of the explanation for this magmatic activity. At depths below 100 km, the tomography results show clear fast anomalies, about 0.3 km/s faster than the reference model, dipping to the northeast that I interpret as the subducting Rivera and Cocos plates. Tomography models show that the Rivera slab is dipping much steeper than the Cocos plate at depth. Below 150 km depth, the Rivera plate shows an almost vertical dip supporting the interpretation that the slab has steepened through time beneath Jalisco leading to a coastward migration of young volcanism with mixed geochemical signatures. The location of the young volcanism of the Jalisco Volcanic Lineament is just at the edge of the steeply dipping slab seen in the tomography. The magmatism is thus likely a nascent arc. The models also display evidence of a gap between the Rivera and Cocos plates that increases in width with depth marking the boundary between the two plates. The gap lies just to the west of Colima graben and allows asthenosphere to rise above the plates feeding Colima volcano. Another interesting finding from this study is a possibility of a slab tear along the western edge of the Cocos plate at a depth of about 50 km extending 60 km horizontally. The tear is coincident with a lack of seismicity in this region although there are events below and above the tear. / text
3

Microplate Kinematics, Intraplate Deformation and Sea Level Rise in Europe

Buble, Goran January 2012 (has links)
The rapid development of space geodesy over the last two decades has had a profound effect on geologic studies by allowing measurements of crustal motion with sub-millimeter per year precision. The focus of this work is to better understand microplate kinematics, intraplate deformation and sea level rise in Europe by use of Global Positioning System (GPS) measurements of crustal deformation. This is accomplished in three separate studies. The first study focuses on crustal motion and sea level rise along the eastern margin of Adria. We use data from tide gauge and continuous GPS (CGPS) stations. We develop a new method to separate common-mode relative sea level from spatially variable signals. From tide gauge data, we find uniform relative sea level rise along the coast that is 2-4 times lower than the estimates for global average sea level rise. In constrast, vertical motion of coastal rocks determined by CGPS varies appreciably from an average of -1.7 ± 0.4 mm/yr in the southern Adria to 0.0 ± 0.4 mm/yr in northern Adria. The most enigmnatical result of this study is that the combination of tide gauge and CGPS data shows that absolute sea level varies in such a way that relative sea level remains constant. The second study focuses on diffuse intraplate deformation of western Eurasia measured by CGPS. We find that our preferred model involves four subplates, separated by the Pyrenees, Rhine Graben, and Trans European Suture Zone, and yields residual velocities indistinguishable from random samples. We interpret the intraplate dormation as the surface manifestation of downwelling mantle lithosphere. The final component of this work is a study of the Northern and Southern Adria microplates' internal stability and tectonic motion. Results show that both Adria microplates are kinematically distinct from one another and from the slowly converging Eurasia and Nubia plates, with implications for the dynamics of the Nubia-Eurasia plate boundary zone. We also find that internal strain within the Adria microplates is statistically insignificant. We estimate appreciable fault slip rates around the periphery of Adria, with implications for slip rates and seismic hazards associated with circum-Adria fault zones.
4

Late Neogene Uplift of the Fairweather Ground on the Basis of Bathymetric and Seismic Data from the Gulf of Alaska

Guarisco, Peter David, IV 16 May 2008 (has links)
Pliocene to Pleistocene glacial-marine deposits adjacent to the Fairweather Ground basement in the Gulf of Alaska are the focus for seismic interpretation using public domain seismic reflection data. The late Tertiary and early Quaternary sections of the Yakataga Formation record a glacial/ interglacial climate change sequence with increasing rates of sedimentation (175 meters per million years to 4000 meters per million years). The foreland basin sediment load is deposited onto the Yakutat block, a microplate that takes up the strike-slip to convergent movement with respect to North America and Pacific plates. Tectonic activity during the last 5 million years has resulted in Eocene rock exposed at the sea floor. High resolution bathymetry data adjacent to the Yakutat microplate is utilized to 1) observe the results of deformation from Pacific plate loading on the Yakutat microplate and 2) interpret the Transition fault as an active thrust to oblique thrust fault.
5

Bio-essais anti-adhésion sur bactéries marines pour le criblage de molécules et de revêtements antifouling / Anti-adhesion bioassay ofmarine bacteria for screening molecules and antifouling coating

Camps, Mercedes 24 June 2011 (has links)
Tout support immergé dans l’eau est rapidement colonisé par de nombreux organismes micro- et macroscopiques. Ce phénomène séquentiel et complexe appelé biofouling est à l’origine de nombreux préjudices économiques et écologiques, notamment dans le milieu marin. L’interdiction récente de certaines substances toxiques, utilisées comme biocides dans les revêtements antifouling des coques de bateaux notamment, a relancé l’intérêt de rechercher de nouvelles molécules antifouling respectueuses de l’environnement. L’objectif de cette thèse a été de développer et d’amorcer l’étude de la représentativité d’un bio-essai permettant d’évaluer le potentiel antifouling de molécules et de revêtements sur des « biofilms » mono et plurispécifiques in vitro en microplaques grâce à l’utilisation de fluorochromes. Le choix a été fait de se focaliser sur le biofilm primaire car il est envisagé que l’élimination ou la limitation de ce dernier réduisent le biofouling. Cinq souches de bactéries marines pionnières, isolées de la Rade de Toulon et en Bretagne, ont été utilisées afin de comparer l’efficacité anti-adhésion de molécules commerciales et naturelles. Deux dérivés de synthèse de substances naturelles marines (TFA E et Z) ont présenté une activité significative associée à une absence de toxicité sur bactéries, suggérant ainsi un mode d’action anti-adhésion spécifique. En outre, les différences de sensibilité entre souches ont confirmée l’importance de réaliser le bio-essai avec un panel diversifié de bactéries.Afin de voir si les données obtenues en laboratoire reflétaient ce qui se produit dans le milieu naturel, une comparaison entre les résultats du bio-essai en microplaque appliqué à six revêtements et les biofilms qui ont colonisés ces mêmes peintures immergées un mois dans la Rade de Toulon (analysés par cytométrie de flux, microscopie et PCR-DGGE), a été effectuée. Les analyses quantitatives ont suggéré une cohérence entre les deux approches même si l’absence de revêtement d’efficacité intermédiaire et le nombre de systèmes testés limite la portée de nos conclusions / Any surface immersed in water is rapidly colonized by a lot of micro-and macroscopic organisms. Sequential and complex phenomenon known as biofouling, lead to major economic and ecological damages, particularly in the marine environment. The recent ban of toxic substances used as biocides in antifouling coatings for ship hulls notably, has relaunched searching for new molecules antifouling environmentally friendly. The objective of this thesis was to develop and initiate the study of the representativeness of a bioassay allow to assess the potential of molecules and antifouling coatings on "biofilms" mono and multi-species microplate using of fluorochromes. It was decided to focus on the primary biofilm because it is possible that the elimination or limitation of the latter reduce biofouling. Five strains of marine bacteria pioneers, isolated from the Bay of Toulon and Brittany, were used to compare the effectiveness of a settlement of commercial and natural molecules. Two derivatives of natural substances Marine (TFA E and Z) showed significant activity associated with a lack of toxicity in bacteria, suggesting a specific anti-adhesion mechanism. In addition, differences in sensitivity between strains have confirmed the importance of making the bioassay with a various bacteria. To see if the data obtained in the laboratory showed what happens in the natural environment, a comparison between the results of the bioassay in microplate applied to six coatings and biofilms isolated on the same paint immersed for a month in the Bay of Toulon (analyzed by flow cytometry, microscopy and PCR-DGGE) was performed. Quantitative analysis suggested a correlation in between approaches although the absence of effectiency intermediate coating and the number of tested systems limit our conclusions
6

Doseamento microbiológico de vancomicina - desenvolvimento e validação de método empregando leitura cinética em microplacas / Microbiological assay of vancomycin - development and validation method using kinetic reading microplate

Botelho, Túlia de Souza 28 January 2011 (has links)
O ensaio turbidimétrico tem como princípio a redução da densidade óptica em suspensões microbianas, decorrente o incremento na concentração do antibiótico. No ensaio convencional trabalha-se com tubos de ensaio que demandam longo tempo para visualização da resposta. Assim, o método empregando microplacas com leitura cinética para a dosagem de antibióticos é de interesse considerável, uma vez que possibilita reduzir quantidade de material e tempo de análise necessários e permite o ensaio de grande número de amostras simultaneamente, com leitura e cálculo automatizado. O objetivo deste trabalho é desenvolver o método de doseamento microbiológico de vancomicina empregando microplacas e modo de leitura cinético, assim como validar o método desenvolvido, através da avaliação dos parâmetros de especificidade e seletividade, linearidade, faixa ou intervalo linear, exatidão e precisão. Adicionalmente foi contemplado desenvolvimento paralelo entre o método convencional e o cinético, de forma a permitir respaldo positivo quanto à validação. Sendo assim, através do estudo dos parâmetros de validação do método cinético, trabalhou-se em condições estabelecidas abrangendo curva-padrão de vancomicina com concentrações entre 0,6 e 1,0 µg/mL, e emprego de meio de cultura caldo de caseína-soja inoculado com Bacillus subtilis (ATCC 6633) na proporção de 5%. Foram obtidos resultados satisfatórios em 5 horas de incubação. Conclui-se que o ensaio em microplacas permite avaliar, com vantagens, a atividade do antibiótico frente ao microrganismo-teste, permitindo facilidade operacional e maior rapidez na obtenção dos resultados. / The principle of the turbidimetric assay is to reduce the optical density of microbial suspensions, due to the increase in the concentration of antibiotic. In the conventional test works with tubes that require long time to display the answer. Thus, the method using microplates with kinetic reading for the dosage of antibiotics is of considerable interest, since it allows possible to reduce the amount of material and analysis time required and allows for testing of large numbers of samples simultaneously, with automated reading and calculating. The aim of this work is to develop the method of microbiological assay of vancomycin using microplates and kinetic reading mode, and to validate the method developed by evaluating the parameters of specificity and selectivity, linearity, linear range, accuracy and precision. Also included was the parallel development between the conventional method and the kinetic, to enable positive support for the validation. Thus, by studying the validation parameters of the kinetic method, worked under conditions laid down covering vancomycin standard curve with concentrations between 0.6 and 1.0 mg / mL, and soybean-casein broth inoculated with 5% of Bacillus subtilis (ATCC 6633). Satisfactory results were obtained with 5 hours incubation. In conclusion, the microplate assay allows to evaluate, with advantages, the activity of the antibiotic against the microorganism, allowing greater operational ease and rapidity of obtaining results.
7

Avaliação de microplacas de titânio em fraturas de tibiotarso em pombos domésticos (Colimba livia)

Gouvea, Aline Silva January 2010 (has links)
Entre os problemas cirúrgicos das aves, as fraturas são os de maior prevalência. Em virtude das variações no tamanho, peso, anatomia óssea peculiar, alta incidência de fraturas complicadas e às diferentes demandas funcionais entre espécies e indivíduos, não foi possível estabelecer ainda um método ideal de osteossíntese para os ossos longos das aves. Por isso, diversos estudos têm sido realizados buscando um método adequado para as diferentes necessidades desses animais. Microplacas de titânio comumente utilizadas em cirurgias maxilofaciais de humanos foram empregadas recentemente na osteossíntese de aves, porém com poucos resultados disponíveis. O objetivo do presente estudo foi avaliar a utilização das microplacas de titânio no tratamento de fraturas experimentais de tibiotarso em pombos domésticos (Columba livia). Foram utilizadas 30 aves, adultas, machos e fêmeas, com 7 meses de idade, pesando entre 400 a 500 gramas, oriundas do Biotério Central da Universidade Federal de Santa Catarina (UFSC). Os animais foram separados aleatoriamente em 3 grupos de dez animais, sendo que no grupo 1 foi utilizado uma microplaca de titânio com 6 furos e espaçador central, no grupo 2 com 8 furos sem espaçador central e no grupo 3 com 8 furos com espaçador central. Após avaliação clínica, as aves foram submetidas a osteotomia médio-diafisária no tibiotarso direito para colocação das diferentes configurações de microplaca de titânio, sendo fixadas com microparafusos de titânio com 7mm de comprimento. Os animais foram avaliados clinica e radiograficamente até os 90 dias de pós-operatório. Após esse período, foi realizada eutanásia em 2 animais de cada grupo. Em todos animais foi observado a consolidação óssea, no grupo 1 o tempo médio e o desvio padrão foram 32,9±9,9; no grupo 2 30,8±6,7 e no grupo 3 26,6±6,4 dias, não havendo diferença estatística entre os grupos. O envergamento do implante foi a complicação mais frequente. A configuração da microplaca resultou em diferença estatística significativa em relação a deambulação e ao grau de envergamento nos diferentes grupos. Sendo que no grupo 3 houve maior precocidade no apoio do membro e menor grau de envergamento em relação aos outros grupos. Histologicamente foi verificado formação de calo ósseo em todos animais e presença de tecido ósseo ao redor da microplaca e microparafusos. Apesar das complicações observadas as microplacas de titânio são uma opção para osteossíntese de tibiotarso em aves de médio porte. / Among the surgical problems in birds, the fractures are the most prevalent. Due to variations in size, weight, peculiar bone anatomy, high incidence of complicated fractures and the functional demands of different species and individuals, is not possible yet to establish an ideal method for osteosynthesis of long bones in birds. Therefore, several studies have been conducted looking for a suitable method for the different needs of these animals. Titanium microplates commonly used in human maxillofacial surgery have been recently employed in osteosynthesis of birds, but with few results available. The aim of this study was to evaluate the use of titanium microplates in the treatment of tibiotarsus fractures in pigeons (Columba livia) 30 birds were used, adult males and females, with 7 months old, weighing from 400 to 500 that came from the Animal Center Facility of the Federal University of Santa Catarina (UFSC). The animals were divided into 3 groups with ten animals each. In group 1 a titanium microplate with 6 holes and a central spacer were used; in group 2 a titanium microplate with 8 holes without a spacer in the center; in group 3 a titanium microplate with 8 holes with central spacer. After clinical evaluation, the birds were submitted to mid-diaphyseal osteotomy in the right bone for placement of different configurations of the titanium plate, and fixed with titanium microscrews 7mm long. The animals were evaluated clinically and radiographically until 90 days postoperatively. After this period, euthanasia was performed in 2 animals from each group. In all animals was observed bone healing and in group 1 the mean and standard deviation were 32.9 ± 9.9, in group 2 30.8 ± 6.7 in group 3 26.6 ± 6.4 days, not having statistical difference in healing time between groups. The bending of the implant was the most common complication. The configuration of the plate resulted in a statistically significant difference in relation to walking and the degree of bending in different groups. Moreover, in group 3 there was higher precocity in the member suppor and a lower degree of bending in relation to other groups. Histologically it was verified the formation of the callus in all animals and the presence of bone tissue around the plate and microscrews. Despite the complications of titanium microplates, they are an option for osteosynthesis of tibiotarsus in birds of medium size.
8

Avaliação de microplacas de titânio em fraturas de tibiotarso em pombos domésticos (Colimba livia)

Gouvea, Aline Silva January 2010 (has links)
Entre os problemas cirúrgicos das aves, as fraturas são os de maior prevalência. Em virtude das variações no tamanho, peso, anatomia óssea peculiar, alta incidência de fraturas complicadas e às diferentes demandas funcionais entre espécies e indivíduos, não foi possível estabelecer ainda um método ideal de osteossíntese para os ossos longos das aves. Por isso, diversos estudos têm sido realizados buscando um método adequado para as diferentes necessidades desses animais. Microplacas de titânio comumente utilizadas em cirurgias maxilofaciais de humanos foram empregadas recentemente na osteossíntese de aves, porém com poucos resultados disponíveis. O objetivo do presente estudo foi avaliar a utilização das microplacas de titânio no tratamento de fraturas experimentais de tibiotarso em pombos domésticos (Columba livia). Foram utilizadas 30 aves, adultas, machos e fêmeas, com 7 meses de idade, pesando entre 400 a 500 gramas, oriundas do Biotério Central da Universidade Federal de Santa Catarina (UFSC). Os animais foram separados aleatoriamente em 3 grupos de dez animais, sendo que no grupo 1 foi utilizado uma microplaca de titânio com 6 furos e espaçador central, no grupo 2 com 8 furos sem espaçador central e no grupo 3 com 8 furos com espaçador central. Após avaliação clínica, as aves foram submetidas a osteotomia médio-diafisária no tibiotarso direito para colocação das diferentes configurações de microplaca de titânio, sendo fixadas com microparafusos de titânio com 7mm de comprimento. Os animais foram avaliados clinica e radiograficamente até os 90 dias de pós-operatório. Após esse período, foi realizada eutanásia em 2 animais de cada grupo. Em todos animais foi observado a consolidação óssea, no grupo 1 o tempo médio e o desvio padrão foram 32,9±9,9; no grupo 2 30,8±6,7 e no grupo 3 26,6±6,4 dias, não havendo diferença estatística entre os grupos. O envergamento do implante foi a complicação mais frequente. A configuração da microplaca resultou em diferença estatística significativa em relação a deambulação e ao grau de envergamento nos diferentes grupos. Sendo que no grupo 3 houve maior precocidade no apoio do membro e menor grau de envergamento em relação aos outros grupos. Histologicamente foi verificado formação de calo ósseo em todos animais e presença de tecido ósseo ao redor da microplaca e microparafusos. Apesar das complicações observadas as microplacas de titânio são uma opção para osteossíntese de tibiotarso em aves de médio porte. / Among the surgical problems in birds, the fractures are the most prevalent. Due to variations in size, weight, peculiar bone anatomy, high incidence of complicated fractures and the functional demands of different species and individuals, is not possible yet to establish an ideal method for osteosynthesis of long bones in birds. Therefore, several studies have been conducted looking for a suitable method for the different needs of these animals. Titanium microplates commonly used in human maxillofacial surgery have been recently employed in osteosynthesis of birds, but with few results available. The aim of this study was to evaluate the use of titanium microplates in the treatment of tibiotarsus fractures in pigeons (Columba livia) 30 birds were used, adult males and females, with 7 months old, weighing from 400 to 500 that came from the Animal Center Facility of the Federal University of Santa Catarina (UFSC). The animals were divided into 3 groups with ten animals each. In group 1 a titanium microplate with 6 holes and a central spacer were used; in group 2 a titanium microplate with 8 holes without a spacer in the center; in group 3 a titanium microplate with 8 holes with central spacer. After clinical evaluation, the birds were submitted to mid-diaphyseal osteotomy in the right bone for placement of different configurations of the titanium plate, and fixed with titanium microscrews 7mm long. The animals were evaluated clinically and radiographically until 90 days postoperatively. After this period, euthanasia was performed in 2 animals from each group. In all animals was observed bone healing and in group 1 the mean and standard deviation were 32.9 ± 9.9, in group 2 30.8 ± 6.7 in group 3 26.6 ± 6.4 days, not having statistical difference in healing time between groups. The bending of the implant was the most common complication. The configuration of the plate resulted in a statistically significant difference in relation to walking and the degree of bending in different groups. Moreover, in group 3 there was higher precocity in the member suppor and a lower degree of bending in relation to other groups. Histologically it was verified the formation of the callus in all animals and the presence of bone tissue around the plate and microscrews. Despite the complications of titanium microplates, they are an option for osteosynthesis of tibiotarsus in birds of medium size.
9

Avaliação de microplacas de titânio em fraturas de tibiotarso em pombos domésticos (Colimba livia)

Gouvea, Aline Silva January 2010 (has links)
Entre os problemas cirúrgicos das aves, as fraturas são os de maior prevalência. Em virtude das variações no tamanho, peso, anatomia óssea peculiar, alta incidência de fraturas complicadas e às diferentes demandas funcionais entre espécies e indivíduos, não foi possível estabelecer ainda um método ideal de osteossíntese para os ossos longos das aves. Por isso, diversos estudos têm sido realizados buscando um método adequado para as diferentes necessidades desses animais. Microplacas de titânio comumente utilizadas em cirurgias maxilofaciais de humanos foram empregadas recentemente na osteossíntese de aves, porém com poucos resultados disponíveis. O objetivo do presente estudo foi avaliar a utilização das microplacas de titânio no tratamento de fraturas experimentais de tibiotarso em pombos domésticos (Columba livia). Foram utilizadas 30 aves, adultas, machos e fêmeas, com 7 meses de idade, pesando entre 400 a 500 gramas, oriundas do Biotério Central da Universidade Federal de Santa Catarina (UFSC). Os animais foram separados aleatoriamente em 3 grupos de dez animais, sendo que no grupo 1 foi utilizado uma microplaca de titânio com 6 furos e espaçador central, no grupo 2 com 8 furos sem espaçador central e no grupo 3 com 8 furos com espaçador central. Após avaliação clínica, as aves foram submetidas a osteotomia médio-diafisária no tibiotarso direito para colocação das diferentes configurações de microplaca de titânio, sendo fixadas com microparafusos de titânio com 7mm de comprimento. Os animais foram avaliados clinica e radiograficamente até os 90 dias de pós-operatório. Após esse período, foi realizada eutanásia em 2 animais de cada grupo. Em todos animais foi observado a consolidação óssea, no grupo 1 o tempo médio e o desvio padrão foram 32,9±9,9; no grupo 2 30,8±6,7 e no grupo 3 26,6±6,4 dias, não havendo diferença estatística entre os grupos. O envergamento do implante foi a complicação mais frequente. A configuração da microplaca resultou em diferença estatística significativa em relação a deambulação e ao grau de envergamento nos diferentes grupos. Sendo que no grupo 3 houve maior precocidade no apoio do membro e menor grau de envergamento em relação aos outros grupos. Histologicamente foi verificado formação de calo ósseo em todos animais e presença de tecido ósseo ao redor da microplaca e microparafusos. Apesar das complicações observadas as microplacas de titânio são uma opção para osteossíntese de tibiotarso em aves de médio porte. / Among the surgical problems in birds, the fractures are the most prevalent. Due to variations in size, weight, peculiar bone anatomy, high incidence of complicated fractures and the functional demands of different species and individuals, is not possible yet to establish an ideal method for osteosynthesis of long bones in birds. Therefore, several studies have been conducted looking for a suitable method for the different needs of these animals. Titanium microplates commonly used in human maxillofacial surgery have been recently employed in osteosynthesis of birds, but with few results available. The aim of this study was to evaluate the use of titanium microplates in the treatment of tibiotarsus fractures in pigeons (Columba livia) 30 birds were used, adult males and females, with 7 months old, weighing from 400 to 500 that came from the Animal Center Facility of the Federal University of Santa Catarina (UFSC). The animals were divided into 3 groups with ten animals each. In group 1 a titanium microplate with 6 holes and a central spacer were used; in group 2 a titanium microplate with 8 holes without a spacer in the center; in group 3 a titanium microplate with 8 holes with central spacer. After clinical evaluation, the birds were submitted to mid-diaphyseal osteotomy in the right bone for placement of different configurations of the titanium plate, and fixed with titanium microscrews 7mm long. The animals were evaluated clinically and radiographically until 90 days postoperatively. After this period, euthanasia was performed in 2 animals from each group. In all animals was observed bone healing and in group 1 the mean and standard deviation were 32.9 ± 9.9, in group 2 30.8 ± 6.7 in group 3 26.6 ± 6.4 days, not having statistical difference in healing time between groups. The bending of the implant was the most common complication. The configuration of the plate resulted in a statistically significant difference in relation to walking and the degree of bending in different groups. Moreover, in group 3 there was higher precocity in the member suppor and a lower degree of bending in relation to other groups. Histologically it was verified the formation of the callus in all animals and the presence of bone tissue around the plate and microscrews. Despite the complications of titanium microplates, they are an option for osteosynthesis of tibiotarsus in birds of medium size.
10

Avaliação in vitro da atividade antibacteriana de extratos de Byrsonima ssp E Alchornea ssp: estudo comparativo entre as técnicas de diluição em tubos e microplacas

Moraes, Helen Pimenta de [UNESP] 28 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-28Bitstream added on 2014-06-13T20:19:00Z : No. of bitstreams: 1 moraes_hp_me_arafcf.pdf: 1421590 bytes, checksum: 13ffb8dfe23f8d17e358dcedf26cd6c1 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O Brasil apresenta uma grande diversidade de plantas medicinais, cuja utilização pela população vem aumentando cada vez mais. Byrsonima (Malpighiaceae) e Alchornea (Euphorbiaceae) que são plantas do Bioma-Cerrado do estado de São Paulo apresentam compostos com grande potencial de atividade biológica, sendo entretanto, pouco estudadas. A atividade antimicrobiana é uma etapa de extrema importância na caracterização biológica de produtos naturais com potencial farmacológico. Nossos objetivos foram investigar a atividade antibacteriana de extratos metanólicos e clorofórmicos de Byrsonima spp. e Alchornea spp empregando as técnicas de diluição em tubos e em microplacas com leitura espectrofotométrica e visual utilizando resazurina como revelador. Foram utilizadas as bactérias: Escherechia coli, Staphylococcus aureus, Yersinia enterocolitica e Aeromonas hydrophila. Nos ensaios em microplacas e em tubos foi determinada a concentração inibitória mínima (CIM) dos extratos vegetais testados à concentração de 1000æg/mL a 31,25æg/mL. Objetivou-se também comparar a eficácia das metodologias empregadas. Nosso estudo demonstrou maior atividade antibacteriana dos extratos metanólicos tanto de Byrsonima quanto de Alchornea, ressaltando os dados obtidos com B. crassa (MeOH) e B. basiloba (MeOH) que apresentaram acentuada atividade antibacteriana frente aos diferentes microrganismos testados. As metodologias empregadas foram eficazes para essa finalidade sendo as de diluição em microplacas mais vantajosas, pelo emprego de pequenos volumes principalmente os de extratos vegetais que são obtidos em pequenas quantidades. Dentre os dois métodos de microdiluição, a que empregava leitura espectrofotométrica apresentou-se mais sensível, porém a de leitura visual mostrou-se mais prática na leitura final e na interpretação dos resultados. / Brazil presents a great diversity of medicinal plants, whose use by people increases more and more. Byrsonima (Malpighiaceae) and Alchornea (Euphorbiaceae) are plants of Bioma-Cerrado of the state of São Paulo and present composites with great potential of biological activity, but, however, they are little studied. The antimicrobial activity is a stage of extreme importance in the biological characterization of natural products with pharmacological potential. Our objectives were to investigate the antibacterial activity of methanolic and chlorophormic extracts of Byrsonima spp and Alchornea spp using the techniques of dilution in tubes and in microplates with spectrophotometric and visual readings using resazurin. Escherichia coli, Staphylococcus aureus, Yersinia enterocolitica and Aeromonas hydrophila were tested. In the microplate and tubes assays, the minimum innhibitory concentration (MIC) of plant extracts were tested in concentrations between 1000æg/mL and 31.25æg/mL. It was also compared the effectiveness of the methodologies employed. Our study demonstrated greater antibacterial activity of methanolic extracts of both Byrsonima and Alchornea, standing out the data obtained for B. crassa (MeOH) and B. basiloba (MeOH), which presented accented antibacterial activity against the different tested microrganisms. The methodologies employed were efficient for this purpose and the microplate dilution assay is more advantageous, for the fact it uses smaller volumes, mainly for those vegetal extracts that normally are obtained in small amounts. Amongst the two methods of microdilution, the one that used spectrophotometric reading proved to be more sensitive, however, the visual reading procedure was shown to be more practical in the final reading and interpretation of the results.

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