968 resultados para PROGRESSIVE DAMAGE ANALYSIS


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Dissertação de mestrado em Structural Analysis of Monuments and Historical Constructions

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Dissertação de mestrado em Structural Analysis of Monuments and Historical Constructions

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OBJECTIVE: To study the quantitative changes in intramyocardial blood vessels in rats in whom nitric oxide synthesis was inhibited. METHODS: Four groups of 10 rats were studied: control (C25 and C40) and L-NAME (L25 and L40). The animals L25 and L40 received L-NAME in the dosage of 50mg/kg/day for 25 and 40 days, respectively. On days 26 and 41 the animals in groups 25 and 40 were sacrificed. Analysis of the myocardium was performed using light microscopy and stereology. RESULTS: Arterial blood pressure and heart weight increased 74.5 and 57.8% after 25 days and 90.2 and 34.6% after 40 days, respectively. Comparing the L-NAME rats with the respective controls revealed that vessel volume density decreased 31.3% after 40 days, and the vessel length-density decreased 53.5% after 25 days and 25.7% after 40 days. The mean cross-sectional area of the vessels showed an important reduction of 154.6% after 25 days. The intramyocardial vessels decreased significantly in length- density in the L-NAME animals. The mean cross-sectional area of the vessels, which normally increases during heart growth between 25 and 40 days, showed a precocious increase by the 25th day in the L-NAME rats. This suggests an increase of the size of the heart, including blood vessels. CONCLUSION: The inhibition of the NO synthesis provokes rarefaction in the intramyocardial vessels that progresses with the time of administration of L-NAME.

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Abordar la infancia desde el enfoque de derechos (ED) implica una lectura de los derechos de los cuales los niños, niñas y adolescentes (NNA) son titulares y de las acciones estatales que se implementan para viabilizar el ejercicio concreto de ellos. Esta perspectiva exige comprender los contenidos de las políticas púb,el grado de participación que se les asigna y los sentidos que ellas toman en términos de progresividad de los derechos. Los cambios de concepción de la infancia desde la Convención Internacional de los Derechos del Niño (CIDN) y los cambios legislativos interpelan al Estado y la sociedad a modificar la visión hegemónica. Nuestra hipótesis gira alrededor de las siguientes considerac.: se han producido algunas modificaciones en las políticas y acciones estatales, aún no se dan las transformaciones necesarias de las lógicas institucionales y de los operadores que estimulen la participación de NNA en el ámbito escolar. Esto se visualiza en la ausencia de análisis cuali de los contenidos de las acc. y la falta de ftes estadísticas específicas, que muestren la orientac.de los contenidos en los principios de la protecc.integral. Estos presupuestos plantean interrogantes que delimitan el problema de investigación: ¿cómo se construye y reconstruye el ejercicio de la ciudadanía a través de la participación de los NNA, en su paso por la escuela, y cuáles son las lógicas institucionales que habilitan u obstaculizan ese ejercicio? Y ¿cuáles son los recursos institucionales que permitan que los programas y acciones redunden en el ejercicio efectivo de los derechos?.Obj.gral: Describir, analizar e interpretar la progresividad en el ejercicio de los derechos de participación e informacióin que tienen los adolescentes en escuelas secundarias de la cd de Cba, durante 2005 / 2010, para promover espacios públicos de construcción de ciudadanía. Se analizarán tres escuelas de Córdoba, escuela pública provincial, púb. nacional y privada. Obj. Espec.: Analizar las prácticas participativas formales e informales en las escuelas seleccionadas.- Aplicar indicadores cuanti y cualitativos del “Sistema de Indicadores para los derechos de la Infancia” Describir y analizar los recursos materiales y humanos. Elaborar y proponer procedim. para la confec. de registros de datos estadísticos - Elaborar y proponer lineamientos para la elaborac.e implementac.de acciones. Diseñar herramientas de difusión sobre los ds de participación e información.Esta investigac. es de carácter descriptivo e interpretativo, analizará diferentes ftes de informac.con técnicas cuanti y cualitativas, durante período la promulgación de la Ley 26061/05 y la adhesión prov. 9396/07. Se tomarán del Sistema de Indicadores, el derecho a la educación, el tema transversal “Acceso a la información y participación”, y las categorías de análisis “Recepción del Derecho y Capacidades estatales”. Se trabajaran indicadores cuanti y señales de progreso (cualitativos): estructurales, proceso y resultados. Serán analizados los Programas implementados durante el período de estudio. Estrategias cuali observac. participante, entrevistas, grupos focales, talleres de sensibilización, etc .Otras ftes de info: doc. institucionales, registros, evaluac, contenidos de programas y campañas y de difusión, prensa escrita, legislaciones, etc. La info se analizará a través Programa Atlas Ti, y del análisis estadístico. Algunos resultados esperados: Evaluac.y ajuste del Sistema de indicadores, la sensibilizac. desde el EF de autorid. escol. para la formulac. de planes y programas para el monitoreo adecuado de los mismos y para la rendic. de ctas de su gestión. Estimular la participac. de NNA en la escuela. Realizac.de documental. Brindar herramientas al Edo para superv de la aplicación progresiva del ejercicio de los derechos de participación e información de NNA Promov la continua evaluac. de los programas y acc.desde el ED para estimular el reconoc. de la nec.de ajuste de la política. The issue of children from the rights focus implies a reading of the rights in which children and adolescents are the holders and the state actions that are implemented to enable the exercise of them. This perspective requires understanding the contents of the public policies, the participation level that is assigned, and the senses that they take in terms of rights progressivity of. The conception changes about children since the International Convention on the Rights of the Child and legislative changes challenge to the State and society to modify hegemony vision. Our hypothesis revolves around the following considerations: there have been some public policies and state actions changes, but they not turn out, yet, transformations in logical institutional and actors whose are encourages children participation in school. This could be reflects in the absence of qualitative analysis in the actions contents and the lack of sources specific statistics, that will be showing the control of the principal contents of integral protection. These, raise the questions that delimit our problem research: how is built citizenship exercise through children and adolescent’s participation in the school, and what are the institutional logical that empowers or turns difficult that exercise? And What are the institutional resources that make possible the effective exercise of the rights, through different programs and actions?. General Objective: To describe, analyze and interpret exercise progressivity participation and information rights that have the adolescents in secondary schools in Córdoba City during 2005 / 2010, in order to promote public spaces for the construction of citizenship. It will analyze three schools in Cordoba, provincial public school, national public school and private school. . Obj. Specifics: To analyze the formal and informal participative practices in the schools selected. - To apply quantitative and qualitative indicators of the “Indicators System for Infa

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The main objective of this thesis on flooding was to produce a detailed report on flooding with specific reference to the Clare River catchment. Past flooding in the Clare River catchment was assessed with specific reference to the November 2009 flood event. A Geographic Information System was used to produce a graphical representation of the spatial distribution of the November 2009 flood. Flood risk is prominent within the Clare River catchment especially in the region of Claregalway. The recent flooding events of November 2009 produced significant fluvial flooding from the Clare River. This resulted in considerable flood damage to property. There were also hidden costs such as the economic impact of the closing of the N17 until floodwater subsided. Land use and channel conditions are traditional factors that have long been recognised for their effect on flooding processes. These factors were examined in the context of the Clare River catchment to determine if they had any significant effect on flood flows. Climate change has become recognised as a factor that may produce more significant and frequent flood events in the future. Many experts feel that climate change will result in an increase in the intensity and duration of rainfall in western Ireland. This would have significant implications for the Clare River catchment, which is already vulnerable to flooding. Flood estimation techniques are a key aspect in understanding and preparing for flood events. This study uses methods based on the statistical analysis of recorded data and methods based on a design rainstorm and rainfall-runoff model to estimate flood flows. These provide a mathematical basis to evaluate the impacts of various factors on flooding and also to generate practical design floods, which can be used in the design of flood relief measures. The final element of the thesis includes the author’s recommendations on how flood risk management techniques can reduce existing flood risk in the Clare River catchment. Future implications to flood risk due to factors such as climate change and poor planning practices are also considered.

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Estudi elaborat a partir d’una estada a l’ Imperial College London, entre juliol i novembre de 2006. En aquest treball s’ha investigat la geometria més apropiada per a la caracterització de la tenacitat a fractura intralaminar de materials compòsits laminats amb teixit. L’objectiu és assegurar la propagació de l’esquerda sense que la proveta falli abans per cap altre mecanisme de dany per tal de permetre la caracterització experimental de la tenacitat a fractura intralaminar de materials compòsits laminats amb teixit. Amb aquesta fi, s’ha dut a terme l’anàlisi paramètrica de diferents tipus de provetes mitjançant el mètode dels elements finits (FE) combinat amb la virtual crack closure technique (VCCT). Les geometries de les provetes analitzades corresponen a la proveta de l’assaig compact tension (CT) i diferents variacions com la extended compact tension (ECT), la proveta widened compact tension (WCT), tapered compact tension (TCT) i doubly-tapered compact tension (2TCT). Com a resultat d’aquestes anàlisis s’han derivat diferents conclusions per obtenir la geometria de proveta més apropiada per a la caracterització de la tenacitat a fractura intralaminar de materials compòsits laminats amb teixit. A més, també s’han dut a terme una sèrie d’assaigs experimentals per tal de validar els resultats de les anàlisis paramètriques. La concordança trobada entre els resultats numèrics i experimentals és bona tot i la presència d’efectes no previstos durant els assaigs experimentals.

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Purpose: To investigate the accuracy of 4 clinical instruments in the detection of glaucomatous damage. Methods: 102 eyes of 55 test subjects (Age mean = 66.5yrs, range = [39; 89]) underwent Heidelberg Retinal Tomography (HRTIII), (disc area<2.43); and standard automated perimetry (SAP) using Octopus (Dynamic); Pulsar (TOP); and Moorfields Motion Displacement Test (MDT) (ESTA strategy). Eyes were separated into three groups 1) Healthy (H): IOP<21mmHg and healthy discs (clinical examination), 39 subjects, 78 eyes; 2) Glaucoma suspect (GS): Suspicious discs (clinical examination), 12 subjects, 15 eyes; 3) Glaucoma (G): progressive structural or functional loss, 14 subjects, 20 eyes. Clinical diagnostic precision was examined using the cut-off associated with the p<5% normative limit of MD (Octopus/Pulsar), PTD (MDT) and MRA (HRT) analysis. The sensitivity, specificity and accuracy were calculated for each instrument. Results: See table Conclusions: Despite the advantage of defining glaucoma suspects using clinical optic disc examination, the HRT did not yield significantly higher accuracy than functional measures. HRT, MDT and Octopus SAP yielded higher accuracy than Pulsar perimetry, although results did not reach statistical significance. Further studies are required to investigate the structure-function correlations between these instruments.

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Studies evaluating the mechanical behavior of the trabecular microstructure play an important role in our understanding of pathologies such as osteoporosis, and in increasing our understanding of bone fracture and bone adaptation. Understanding of such behavior in bone is important for predicting and providing early treatment of fractures. The objective of this study is to present a numerical model for studying the initiation and accumulation of trabecular bone microdamage in both the pre- and post-yield regions. A sub-region of human vertebral trabecular bone was analyzed using a uniformly loaded anatomically accurate microstructural three-dimensional finite element model. The evolution of trabecular bone microdamage was governed using a non-linear, modulus reduction, perfect damage approach derived from a generalized plasticity stress-strain law. The model introduced in this paper establishes a history of microdamage evolution in both the pre- and post-yield regions

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Hemorrhage and resuscitation (H/R) leads to phosphorylation of mitogen-activated stress kinases, an event that is associated with organ damage. Recently, a specific, cell-penetrating, protease-resistant inhibitory peptide of the mitogen-activated protein kinase c-JUN N-terminal kinase (JNK) was developed (D-JNKI-1). Here, using this peptide, we tested if inhibition of JNK protects against organ damage after H/R. Male Sprague-Dawley rats were treated with D-JNKI-1 (11 mg/kg, i.p.) or vehicle. Thirty minutes later, rats were hemorrhaged for 1 h to a MAP of 30 to 35 mmHg and then resuscitated with 60% of the shed blood and twice the shed blood volume as Ringer lactate. Tissues were harvested 2 h later. ANOVA with Tukey post hoc analysis or Kruskal-Wallis ANOVA on ranks, P < 0.05, was considered significant. c-JUN N-terminal kinase inhibition decreased serum alanine aminotransferase activity as a marker of liver injury by 70%, serum creatine kinase activity by 67%, and serum lactate dehydrogenase activity by 60% as compared with vehicle treatment. The histological tissue damage observed was blunted after D-JNKI-1 pretreatment both for necrotic and apoptotic cell death. Hepatic leukocyte infiltration and serum IL-6 levels were largely diminished after D-JNKI-1 pretreatment. The extent of oxidative stress as evaluated by immunohistochemical detection of 4-hydroxynonenal was largely abrogated after JNK inhibition. After JNK inhibition, activation of cJUN after H/R was also reduced. Hemorrhage and resuscitation induces a systemic inflammatory response and leads to end-organ damage. These changes are mediated, at least in part, by JNK. Therefore, JNK inhibition deserves further evaluation as a potential treatment option in patients after resuscitated blood loss.

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Reticulitermes santonensis is a subterranean termite that invades urban areas in France and elsewhere where it causes damage to human-built structures. We investigated the breeding system, colony and population genetic structure, and mode of dispersal of two French populations of R. santonensis. Termite workers were sampled from 43 and 31 collection points, respectively, from a natural population in west-central France (in and around the island of Oleron) and an urban population (Paris). Ten to 20 workers per collection point were genotyped at nine variable microsatellite loci to determine colony identity and to infer colony breeding structure. There was a total of 26 colonies, some of which were spatially expansive, extending up to 320 linear metres. Altogether, the analysis of genotype distribution, F-statistics and relatedness coefficients suggested that all colonies were extended families headed by numerous neotenics (nonwinged precocious reproductives) probably descended from pairs of primary (winged) reproductives. Isolation by distance among collection points within two large colonies from both populations suggested spatially separated reproductive centres with restricted movement of workers and neotenics. There was a moderate level of genetic differentiation (F(ST) = 0.10) between the Oleron and Paris populations, and the number of alleles was significantly higher in Oleron than in Paris, as expected if the Paris population went through bottlenecks when it was introduced from western France. We hypothesize that the diverse and flexible breeding systems found in subterranean termites pre-adapt them to invade new or marginal habitats. Considering that R. santonensis may be an introduced population of the North American species R. flavipes, a breeding system consisting primarily of extended family colonies containing many neotenic reproductives may facilitate human-mediated spread and establishment of R. santonensis in urban areas with harsh climates.

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Rapidly progressive glomerulonephritis (RPG) is a rare clinical syndrome characterized by kidney damage that can lead to irreversible kidney failure. RPG can be caused by primary glomerular disease or can be part of a systemic autoimmune disorder. All RPG have a similar pathophysiology (proliferation of cells in Bowman's capsule and formation of crescents) and clinical evolution (rapidly progressive kidney failure with proteinuria and an active urine sediment). Immunosuppressive therapy and sometimes plasma exchanges are required. Overall- and kidney survival are closely linked to the blood creatinine level at presentation, the percentage of damaged glomeruli, and to the underlying cause. RPG is therefore a diagnostic and therapeutic emergency that needs quick referral to a nephrologist.

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Elderly individuals display a rapid age-related increase in intraindividual variability (IIV) of their performances. This phenomenon could reflect subtle changes in frontal lobe integrity. However, structural studies in this field are still missing. To address this issue, we computed an IIV index for a simple reaction time (RT) task and performed magnetic resonance imaging (MRI) including voxel based morphometry (VBM) and the tract based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) in 61 adults aged from 22 to 88 years. The age-related IIV increase was associated with decreased fractional anisotropy (FA) as well as increased radial (RD) and mean (MD) diffusion in the main white matter (WM) fiber tracts. In contrast, axial diffusion (AD) and grey matter (GM) densities did not show any significant correlation with IIV. In multivariate models, only FA has an age-independent effect on IIV. These results revealed that WM but not GM changes partly mediated the age-related increase of IIV. They also revealed that the association between WM and IIV could not be only attributed to the damage of frontal lobe circuits but concerned the majority of interhemispheric and intrahemispheric corticocortical connections.

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Integrative and conjugative elements (ICE) are in some ways parasitic mobile DNA that propagate vertically through replication with the bacterial host chromosome but at low frequencies can excise and invade new recipient cells through conjugation and reintegration (horizontal propagation). The factors that contribute to successful horizontal propagation are not very well understood. Here, we study the influence of host cell life history on the initiation of transfer of a model ICE named ICEclc in bacteria of the genus Pseudomonas. We use time-lapse microscopy of growing and stationary-phase microcolonies of ICEclc bearing cells in combination with physiological staining and gene reporter analysis in stationary-phase suspended cells. We provide evidence that cell age and cell lineage are unlikely to play a role in the decision to initiate the ICEclc transfer program. In contrast, cells activating ICEclc show more often increased levels of reactive oxygen species and membrane damage than nonactivating cells, suggesting that some form of biochemical damage may make cells more prone to ICEclc induction. Finally, we find that ICEclc active cells appear spatially at random in a microcolony, which may have been a selective advantage for maximizing ICEclc horizontal transmission to new recipient species.

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The hypothalamic damage induced by neonatal treatment with monosodium l-glutamate (MSG) induces several metabolic abnormalities, resulting in a rat hyperleptinemic-hyperadipose phenotype. This study was conducted to explore the impact of the neonatal MSG treatment, in the adult (120 days old) female rat on: (a) the in vivo and in vitro mineralocorticoid responses to ACTH and angiotensin II (AII); (b) the effect of leptin on ACTH- and AII-stimulated mineralocorticoid secretions by isolated corticoadrenal cells; and (c) abdominal adiposity characteristics. Our data indicate that, compared with age-matched controls, MSG rats displayed: (1) enhanced and reduced mineralocorticoid responses to ACTH and AII treatments, respectively, effects observed in both in vivo and in vitro conditions; (2) adrenal refractoriness to the inhibitory effect of exogenous leptin on ACTH-stimulated aldosterone output by isolated adrenocortical cells; and (3) distorted omental adiposity morphology and function. This study supports that the adult hyperleptinemic MSG female rat is characterized by enhanced ACTH-driven mineralocorticoid function, impaired adrenal leptin sensitivity, and disrupted abdominal adiposity function. MSG rats could counteract undesirable effects of glucocorticoid excess, by developing a reduced AII-driven mineralocorticoid function. Thus, chronic hyperleptinemia could play a protective role against ACTH-mediated allostatic loads in the adrenal leptin resistant, MSG female rat phenotype.

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Laser desorption ionisation mass spectrometry (LDI-MS) has demonstrated to be an excellent analytical method for the forensic analysis of inks on a questioned document. The ink can be analysed directly on its substrate (paper) and hence offers a fast method of analysis as sample preparation is kept to a minimum and more importantly, damage to the document is minimised. LDI-MS has also previously been reported to provide a high power of discrimination in the statistical comparison of ink samples and has the potential to be introduced as part of routine ink analysis. This paper looks into the methodology further and evaluates statistically the reproducibility and the influence of paper on black gel pen ink LDI-MS spectra; by comparing spectra of three different black gel pen inks on three different paper substrates. Although generally minimal, the influences of sample homogeneity and paper type were found to be sample dependent. This should be taken into account to avoid the risk of false differentiation of black gel pen ink samples. Other statistical approaches such as principal component analysis (PCA) proved to be a good alternative to correlation coefficients for the comparison of whole mass spectra.