908 resultados para Damage identification in structures


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Since its identification in the 1990s, the RNA interference (RNAi) pathway has proven extremely useful in elucidating the function of proteins in the context of cells and even whole organisms. In particular, this sequence-specific and powerful loss-of-function approach has greatly simplified the study of the role of host cell factors implicated in the life cycle of viruses. Here, we detail the RNAi method we have developed and used to specifically knock down the expression of ezrin, an actin binding protein that was identified by yeast two-hybrid screening to interact with the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) spike (S) protein. This method was used to study the role of ezrin, specifically during the entry stage of SARS-CoV infection.

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A proteção das Infraestruturas Críticas tornou-se numa questão essencial no sistema internacional e nos Estados. Mais recentemente, Portugal começou a acompanhar esta tendência. Neste debate, torna-se de crucial importância, a identificação das infraestruturas que devem ser consideradas como críticas. Esta identificação terá como principal objetivo a redução das suas vulnerabilidades e a eficiência no emprego de recursos para a proteção das mesmas. Mas que critérios e indicadores, em cada setor/subsetor, possibilitam uma adequada metodologia para a identificação e caraterização das Infraestruturas Críticas em Portugal? Com vista a responder a esta problemática será analisada a metodologia adotada por Portugal, bem como as componentes da metodologia de identificação e caraterização de Infraestruturas Críticas utilizadas em países e organizações de referência. Esta investigação tem como objetivo geral identificar de áreas de melhoria na metodologia adotada pela Autoridade Nacional de Proteção Civil e, com base na análise da metodologia usada em organizações e países de referência, contribuir para a identificação e caraterização das IC em Portugal. Conclui-se que a Identificação e Caraterização de Infraestruturas Críticas nacionais deve ser aplicada na primeira fase do processo de elaboração do Programa Nacional de Proteção de Infraestruturas Críticas, apresentando, simultaneamente, uma definição de Infraestrutura Crítica, através de possíveis agrupamentos em setores, critérios e indicadores a adotar. Abstract: Critical infrastructure protection has become a key issue for states in the international system. Recently, Portugal has joined this trend. In this debate, the identification of structures to be considered critical infrastructure becomes crucial. This process of identification should have as key purpose the reduction of these infrastructures, and an efficient use of resources in protecting them. However, which criteria and indicators, for each sector/ sub-sector, allow for an adequate methodology for identifying and characterizing critical infrastructures in Portugal? In order to answer this, this research will analyse the methodology adopted by the National Civil Protection Authority, as well as some methodology components for identifying and characterizing critical infrastructure used by reference countries and organizations. The main purpose of this research is thus to contribute to the development of a methodology to be used in Portugal, through the development of criteria and indicators that prove adequate to identifying and characterizing Portuguese critical infrastructure. It concludes that the identification and characterization of national critical infrastructures should be applied in the first phase of elaborating a national program for the protection of critical infrastructures, while simultaneously presenting a definition of critical infrastructure, through possible grouping in sectors, criteria and indicators to adopt.

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The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective

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In exploring the role of social influences in the development of the self, the current study evaluated whether young adults use social comparisons in developing their hoped-for possible selves and, if so, whether their developmental process correlates with self-regulatory processes and positive mental health outcomes. The current study found the following: (1) the domains of hoped-for possible selves among young adults were related to the gender of the social comparison target, (2) the direction of young adults’ social comparison processes (upward or downward) did not significantly influence self-regulatory processes (self-efficacy and outcome expectancy) toward achieving their hoped-for possible selves, (3) strong masculine gender identification related to greater outcome expectancy, while strong feminine gender identification related to both greater self-efficacy and outcome expectancy, and (4) self-efficacy related to less state anxiety, trait anxiety, and depression, while outcome expectancy related only to less trait anxiety. Males and females were found to use traditional gender role identification in forming their hoped-for possible selves.

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Thesis (Master, Biomedical & Molecular Sciences) -- Queen's University, 2016-08-23 15:03:30.807

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The application of 3D grain-based modelling techniques is investigated in both small and large scale 3DEC models, in order to simulate brittle fracture processes in low-porosity crystalline rock. Mesh dependency in 3D grain-based models (GBMs) is examined through a number of cases to compare Voronoi and tetrahedral grain assemblages. Various methods are used in the generation of tessellations, each with a number of issues and advantages. A number of comparative UCS test simulations capture the distinct failure mechanisms, strength profiles, and progressive damage development using various Voronoi and tetrahedral GBMs. Relative calibration requirements are outlined to generate similar macro-strength and damage profiles for all the models. The results confirmed a number of inherent model behaviors that arise due to mesh dependency. In Voronoi models, inherent tensile failure mechanisms are produced by internal wedging and rotation of Voronoi grains. This results in a combined dependence on frictional and cohesive strength. In tetrahedral models, increased kinematic freedom of grains and an abundance of straight, connected failure pathways causes a preference for shear failure. This results in an inability to develop significant normal stresses causing cohesional strength dependence. In general, Voronoi models require high relative contact tensile strength values, with lower contact stiffness and contact cohesional strength compared to tetrahedral tessellations. Upscaling of 3D GBMs is investigated for both Voronoi and tetrahedral tessellations using a case study from the AECL’s Mine-by-Experiment at the Underground Research Laboratory. An upscaled tetrahedral model was able to reasonably simulate damage development in the roof forming a notch geometry by adjusting the cohesive strength. An upscaled Voronoi model underestimated the damage development in the roof and floor, and overestimated the damage in the side-walls. This was attributed to the discretization resolution limitations.

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Ricerche nel campo del danno renale acuto e frazioni urinarie escrete. La prima parte verte sull’analisi dei dati provenienti da una casistica di cani con leptospirosi, sono stati confrontati due gruppi di cani, il primo con AKI da leptospirosi e l’altro con AKI per eziologie differenti. In queste due popolazioni di pazienti abbiamo valutato alcuni analiti sierici ed urinari come ad esempio l’escrezione elettrolitica frazionata e biomarker di AKI come NGAL. I cani con leptospirosi, hanno mostrato maggiore kaliuresi e più grave glicosuria rispetto a quelli non affetti da leptospirosi, così come erano più frequentemente glicosurici rispetto agli altri. Questi dati sono in analogia con quanto è riportato nell’uomo e dimostrano un pattern di danno tubulare tipico in corso di questa malattia se paragonato appunto ad altre cause di danno tubulare acuto e AKI La seconda parte riguarda la valutazione della funzionalità renale e del danno renale acuto in cani affetti da insufficienza valvolare mitralica. E’ stata incentrata sul danno renale in corso di cardiopatie e per questa ragione abbiamo pensato di valutare esclusivamente pazienti con MVD per varie ragioni: poiché sono pazienti che si presentano frequentemente nella pratica clinica; la malattia è tipicamente cronica e il paziente rimane stabile a lungo con un andamento progressivo della malattia; questi pazienti possono presentare frequenti episodi di AKI legati allo scompenso cardiaco e/o alla terapia con diuretico 3/o ace-i che questi animali ricevono. Abbiamo valutato prospetticamente l'impatto della terapia orale con furosemide sulla chimica urinaria, nei cani con malattia della valvola mitrale mixomatosa. Tali differenze sono state attribuite all'effetto della terapia con furosemide sugli elettroliti renali. La chimica urinaria è utile per stimare la risposta diuretica nei cani con malattie cardiache. I dati suggeriscono differenze significative tra i diversi stadi ACVIM con particolare riferimento all’escrezione elettrolitica di Sodio, Potassio e Cloro.

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Spiking Neural Networks (SNNs) are bio-inspired Artificial Neural Networks (ANNs) utilizing discrete spiking signals, akin to neuron communication in the brain, making them ideal for real-time and energy-efficient Cyber-Physical Systems (CPSs). This thesis explores their potential in Structural Health Monitoring (SHM), leveraging low-cost MEMS accelerometers for early damage detection in motorway bridges. The study focuses on Long Short-Term SNNs (LSNNs), although their complex learning processes pose challenges. Comparing LSNNs with other ANN models and training algorithms for SHM, findings indicate LSNNs' effectiveness in damage identification, comparable to ANNs trained using traditional methods. Additionally, an optimized embedded LSNN implementation demonstrates a 54% reduction in execution time, but with longer pre-processing due to spike-based encoding. Furthermore, SNNs are applied in UAV obstacle avoidance, trained directly using a Reinforcement Learning (RL) algorithm with event-based input from a Dynamic Vision Sensor (DVS). Performance evaluation against Convolutional Neural Networks (CNNs) highlights SNNs' superior energy efficiency, showing a 6x decrease in energy consumption. The study also investigates embedded SNN implementations' latency and throughput in real-world deployments, emphasizing their potential for energy-efficient monitoring systems. This research contributes to advancing SHM and UAV obstacle avoidance through SNNs' efficient information processing and decision-making capabilities within CPS domains.

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Tomatoes are one of the most important vegetable crops grown in Brazil and are among the crops that have one of the highest post-harvest losses indexes in the country. The present work aimed at evaluating impact damage observed in packing lines of fresh tomatoes as well as to determine, under laboratory conditions, quality alterations of tomato fruits submitted to impact damage in different surface types. Critical points evaluation was accomplished using an instrumented sphere. Critical transference points found showed variations in acceleration levels from 30 to 129 G (m s-2). Tests carried out under laboratory conditions showed that padded surfaces reduced up to 31% impact damage. Incidence of severe internal physical damage was evaluated by a subjective scale and increased by 79% on hard surfaces for the highest fall drop. On the other hand, it was observed an effective reduction in physical damage on fruits when padded surfaces were used. When a 10-cm drop was performed, the maximum reduction measured was 10% for hard surfaces and 5% for previously padded surfaces. For quality parameters, it was observed for high drops on hard surfaces, highest values for weight loss, total acidity, lower values for vitamin C and Soluble Solids.

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Este artigo de revisão sistemática tem por objetivo citar os métodos de identificação humana por meio da radiologia, utilizados em odontologia legal. Para isso, realizou-se revisão de literatura com 19 trabalhos selecionados dentre 45 encontrados, após aplicação de critérios de inclusão. Há diversas técnicas radiológicas que podem ser utilizadas para auxiliar na identificação humana, tanto individual como geral, incluindo a determinação do gênero, do grupo étnico e, principalmente, da idade. A análise de radiografias e tomografias ante-mortem e post-mortem tornou-se uma ferramenta fundamental nos processos de identificação em odontologia legal, principalmente com o refinamento das técnicas adquiridas com o avanço da própria radio-logia e com a incorporação da informática. Conclui-se que a partir do conhecimento adequado dos métodos disponíveis, o profissional em odontologia legal pode optar pelo método que melhor preencha as características necessárias para o sucesso da identificação, tendo cuidado na aplicação correta da técnica e na interpretação precisa das informações obtidas.

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A cor é um atributo perceptual que nos permite identificar e localizar padrões ambientais de mesmo brilho e constitui uma dimensão adicional na identificação de objetos, além da detecção de inúmeros outros atributos dos objetos em sua relação com a cena visual, como luminância, contraste, forma, movimento, textura, profundidade. Decorre daí a sua importância fundamental nas atividades desempenhadas pelos animais e pelos seres humanos em sua interação com o ambiente. A psicofísica visual preocupa-se com o estudo quantitativo da relação entre eventos físicos de estimulação sensorial e a resposta comportamental resultante desta estimulação, fornecendo dessa maneira meios de avaliar aspectos da visão humana, como a visão de cores. Este artigo tem o objetivo de mostrar diversas técnicas eficientes na avaliação da visão cromática humana através de métodos psicofísicos adaptativos.

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Background: Leprosy is a chronic granulomatous infectious disease and is still endemic in many parts of the world. It causes disabilities which are the consequence of nerve damage. This damage is in most cases the result of immunological reactions. Objectives: To investigate the differences between a type 1 leprosy (reversal) reaction and relapse on using histopathology. Methods: The histopathological changes in 167 biopsies from 66 leprosy patients were studied. The patients were selected when their sequential biopsies demonstrated either different patterns or maintained the same pattern of granulomatous reaction over more than two years during or after the treatment of leprosy. Results: In 57 of the patients studied, a reactivation was seen which coincided with a decrease in the bacteriological index (BI), suggesting that this reactivation (reversal reaction or type 1 leprosy reaction) coincides with an effective capacity for bacteriological clearance. In nine patients, an increase of the bacteriologic index (IB) or persistence of solid bacilli occurred during the reactivation, indicating proliferative activity, suggestive of a relapse. The histopathological aspects of the granulomas were similar in both groups. Conclusion: Bacterioscopy provided the only means to differentiate a reversal reaction from a relapse in patients with granulomatous reactivation. The type 1 leprosy reaction may be considered as a part effective immune reconstitution (reversal, upgrading reaction) or as a mere hypersensitivity reaction (downgrading reaction) in a relapse.

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A new species of land planarian from Colombia, Gigantea maupoi sp. nov., is described herein. The penis papilla of the new species is provided with numerous accessory genital organs, or mgo. These mgo are of a unique morphology, consisting of a very strong barrel-shaped circular muscle coat and an underlying longitudinal one, both derived from the subepithelial musculature of the penis papilla. The central mass of each mgo contains secretions and 8-15 canalicula that open to the male atrium on the central region of the organ. Differences in structures constituting the mgo and details of the muscular systems and of the reproductive organs among the 11 Gigantea species from literature and from type material of G. bistriata (Hyman, 1962), G. chiriquii (Hyman, 1962), and G. sandersoni (Prudhoe, 1949) reexamined here show that the genus is heterogeneous.

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In the first paper of this paper (Part I), conditions were presented for the gas cleaning technological route for environomic optimisation of a cogeneration system based in a thermal cycle with municipal solid waste incineration. In this second part, an environomic analysis is presented of a cogeneration system comprising a combined cycle composed of a gas cycle burning natural gas with a heat recovery steam generator with no supplementary burning and a steam cycle burning municipal solid wastes (MSW) to which will be added a pure back pressure steam turbine (another one) of pure condensation. This analysis aims to select, concerning some scenarios, the best atmospheric pollutant emission control routes (rc) according to the investment cost minimisation, operation and social damage criteria. In this study, a comparison is also performed with the results obtained in the Case Study presented in Part I. (c) 2007 Elsevier Ltd. All rights reserved.

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In this study, twenty hydroxylated and acetoxylated 3-phenylcoumarin derivatives were evaluated as inhibitors of immune complex-stimulated neutrophil oxidative metabolism and possible modulators of the inflammatory tissue damage found in type III hypersensitivity reactions. By using lucigenin- and luminol-enhanced chemiluminescence assays (CL-luc and CL-lum, respectively), we found that the 6,7-dihydroxylated and 6,7-diacetoxylated 3-phenylcoumarin derivatives were the most effective inhibitors. Different structural features of the other compounds determined CL-luc and/or CL-lum inhibition. The 2D-QSAR analysis suggested the importance of hydrophobic contributions to explain these effects. In addition, a statistically significant 3D-QSAR model built applying GRIND descriptors allowed us to propose a virtual receptor site considering pharmacophoric regions and mutual distances. Furthermore, the 3-phenylcoumarins studied were not toxic to neutrophils under the assessed conditions. (C) 2007 Elsevier Masson SAS. All rights reserved.