728 research outputs found

    Towards a Generic Trace for Rule Based Constraint Reasoning

    Get PDF
    CHR is a very versatile programming language that allows programmers to declaratively specify constraint solvers. An important part of the development of such solvers is in their testing and debugging phases. Current CHR implementations support those phases by offering tracing facilities with limited information. In this report, we propose a new trace for CHR which contains enough information to analyze any aspects of \CHRv\ execution at some useful abstract level, common to several implementations. %a large family of rule based solvers. This approach is based on the idea of generic trace. Such a trace is formally defined as an extension of the ωr∨\omega_r^\lor semantics of CHR. We show that it can be derived form the SWI Prolog CHR trace

    Design e ergonomia: aspectos tecnológicos

    Get PDF
    Nesta coletânea são apresentadas diferentes questões, métodos de abordagem e demandas para a aplicação da Ergonomia no Design. A evolução tecnológica observada nas últimas décadas proporcionou inúmeros benefícios para o aumento na qualidade de vida das pessoas, mas também resultou em vários problemas de interface tecnológica, os quais geram constrangimentos, acidentes, e frustração aos consumidores. Tais questões são analisadas no livro, no qual se destacam temas de grande atualidade, como por exemplo: o uso de equipamentos médico-hospitalares por indivíduos obesos e de cadeiras de rodas por indivíduos idosos; as avaliações ergonômicas de espaços e equipamentos escolares; as dificuldades de leitura em rótulos e bulas de embalagens; o uso de colete de proteção nas atividades policiais, de calçados femininos com salto alto ou da poltrona do motorista de ônibus urbano, entre outros. Os artigos relatam pesquisas desenvolvidas no Programa de Pós-graduação em Design da UNESP, Campus Bauru, e ressaltam a importância da aplicação da ergonomia no design de produtos e sistemas, com a finalidade de se desenvolver tecnologias para melhorar a qualidade de vida humana

    N-acetylcysteine attenuates the progression of chronic renal failure

    Get PDF
    N-acetylcysteine attenuates the progression of chronic renal failure.BackgroundLipid peroxidation impairs renal function. Aldosterone contributes to renal injury in the remnant kidney model. This study aimed to determine the effects of the antioxidant N-acetylcysteine (NAC) on renal function and aldosterone levels in chronic renal failure.MethodsAdult male Wistar rats were submitted to 5/6 nephrectomy or laparotomy (sham-operated) and received NAC (600 mg/L in drinking water, initiated on postoperative day 7 or 60), spironolactone (1.5 g/kg of diet initiated on postoperative day 7), the NAC-spironolactone combination or no treatment. Clearance studies were performed on postoperative days 21, 60, and 120.ResultsMean daily NAC and spironolactone ingestion was comparable among the treated groups. Mean weight gain was higher in NAC-treated rats than in untreated rats. A significant decrease in urinary thiobarbituric acid reactive substances (TBARS) concentrations, a lipid peroxidation marker, was observed in NAC-treated rats. By day 120, glomerular filtration rate (GFR), which dropped dramatically in untreated rats, was stable (albeit below normal) in NAC-treated rats, which also presented lower proteinuria, glomerulosclerosis index, and blood pressure, together with attenuated cardiac and adrenal hypertrophy. These beneficial effects, observed even when NAC was initiated on postnephrectomy day 60, were accompanied by a significant reduction in plasma aldosterone and urinary sodium/potassium ratio. The NAC-spironolactone combination lowered blood pressure and improved GFR protection.ConclusionThe NAC-spironolactone combination improves renal function more than does NAC alone. In the remnant kidney model, early or late NAC administration has a protective effect attributable to decreased plasma aldosterone and lower levels of lipid peroxidation

    Fiber Post Etching with Hydrogen Peroxide: Effect of Concentration and Application Time

    Get PDF
    AbstractIntroductionEtching is necessary to expose the fibers and enable both mechanical and chemical bonding of the resin core to the fiber post. This study evaluated the effect of concentration and application time of hydrogen peroxide on the surface topography and bond strength of glass fiber posts to resin cores.MethodsFiber posts were etched with 24% or 50% hydrogen peroxide for 1, 5, or 10 min (n = 10). Posts without any treatment were used as a control. After etching, the posts were silanated and adhesive resin was applied. The posts were positioned into a mold to allow a self-cured resin core to be inserted. The post/resin assembly was serially sectioned into five beams that were subjected to a tensile bond strength test. Data were subjected to two-way ANOVA and Tukey test (α = 0.05). The surface topography was analyzed using scanning electronic microscopy.ResultsNon-etched post presents a relatively smooth surface without fiber exposure. Application of hydrogen peroxide increased the surface roughness and exposed the fibers. All experimental conditions yielded similar bond strength values that were higher than those obtained in the control group.ConclusionBoth 24% and 50% hydrogen peroxide exposure increased the bond strength of resin to the posts, irrespective of the application time

    Design and evaluation of a natural interface for remote operation of underwater roter

    Get PDF
    Nowadays, an increasing need of intervention robotic systems can be observed in all kind of hazardous environments. In all these intervention systems, the human expert continues playing a central role from the decision making point of view. For instance, in underwater domains, when manipulation capabilities are required, only Remote Operated Vehicles, commercially available, can be used, normally using master-slave architectures and relaying all the responsibility in the pilot. Thus, the role played by human- machine interfaces represents a crucial point in current intervention systems. This paper presents a User Interface Abstraction Layer and introduces a new procedure to control an underwater robot vehicle by using a new intuitive and immersive interface, which will show to the user only the most relevant information about the current mission. Finally, some experiments have been carried out to compare a traditional setup and the new procedure, demonstrating reliability and feasibility of our approach.This research was partly supported by Spanish Ministry of Research and Innovation DPI2011-27977-C03 (TRITON Project)

    A natural interface for remote operation of underwater robots

    Get PDF
    Nowadays, an increasing need of intervention robotic systems can be observed in all kind of hazardous environments. In all these intervention systems, the human expert continues playing a central role from the decision-making point of view. For instance, in underwater domains, when manipulation capabilities are required, only Remote Operated Vehicles, commercially available, can be used, normally using master-slave architectures and relaying all the responsibility in the pilot. Thus, the role played by human- machine interfaces represents a crucial point in current intervention systems. This paper presents a User Interface Abstraction Layer and introduces a new procedure to control an underwater robot vehicle by using a new intuitive and immersive interface, which will show to the user only the most relevant information about the current mission. We conducted an experiment and found that the highest user preference and performance was in the immersive condition with joystick navigation.This research was partly supported by Spanish Ministry of Research and Innovation DPI2011-27977-C03 (TRITON Project)

    Seismic characterization of fluid migration and Pockmarks in the Estremadura Spur, West Iberian Margin, Portugal

    Get PDF
    Recently a field with more than 70 pockmarks was discovered in the NW region of the Estremadura Spur outer shelf (West Iberian margin), a trapezoidal promontory elongated in an east-west direction, between Cabo Carvoeiro and Cabo da Roca, extending until the Tore seamount. Pockmarks are the seabed culminations of fluid migration through the sedimentary column and their characteristic seabed morphologies correspond to cone-shaped circular or elliptical depressions. These features and the associated fluid escape process are the main objectives of this work. Here we characterize these structures to understand their structural and stratigraphic control based on: 1) Seismic processing and interpretation of the high resolution 2D single-channel sparker seismic dataset, 2) Bathymetric and Backscatter interpretation and 3) ROV direct observation of the seafloor. The analysis of the seismic profiles allowed the identification of six seismic units, disturbed by the migration and accumulation of fluids. The Estremadura Spur outer shelf has been affected by several episodes of fluid migration and fluid escape during the Pliocene-Quaternary that are expressed by a vast number of seabed and buried pockmarks. At present, the pockmarks are mainly inactive, as the seabed pockmarks are covered by recent sediments. The stacking of various pockmarks suggests a cyclical fluid flow activity that can possibly be the result of the eustatic sea level variations and the subsequent changes of the hydrostatic pressure. The origin of the seep fluids is still under debate but considering the low-sedimentation rate of the area and the low productivity a deep source for the fluids is most probable, possibly related with the Jurassic hydrocarbon system. It was concluded that the migration of fluids to the seabed occurred over the Pliocene-Quaternary in several episodes, as indicated by the buried pockmarks at different depths. Acknowledgements: This work was carried out in the framework of the PES project - Pockmarks and fluid seepage in the Estremadura Spur: implications for regional geology, biology, and petroleum systems (PTDC/GEOFIQ/5162/2014) financed by the Portuguese Foundation for Science and Technology (FCT). The seismic dataset was acquired within the PACEMAKER project funded by the European Research Council (ERC) under the European Union’s Seventh Framework Program (FP7/2007-2013) ERC agreement (226600). The Instituto Portugues do Mar e da Atmosfera acknowledges support by Landmark Graphics (SeisWorks) via the Landmark University Grant Program. We thank the Estrutura de Missão para a Extensão da Plataforma Continental (EMEPC) for allowing me to have access and use the data collected in the Estremadura Spur during the EMEPC/PEPC/LUSO/2015 cruise and the ROV Luso team. We also thank Prof. Dr. Luis Matias (FCUL & IDL) for the help with SPW and processing steps

    Qualidade ovocitária de tambaqui (Colossoma macropomum) ao longo da estação reprodutiva

    Get PDF
    The study aimed to analyze the Colossoma macropomum reproductive behavior and quality of the female gametes throughout the reproductive season. The experiment was carried out in Pimenta Bueno - Rondônia State (Northern Brazil) during the reproductive season (2010-2011) using 36 females. Each sampling was performed on a 15 ± 5 days interval. Female gametes were collected by stripping and the following analyses were performed: weight of oocytes released (g); productivity index, fertilization and hatching rate. During the sampling period was verified effect (p < 0.05) of collecting time into the season for oocytes weight, productivity index and fertilization rate. Although the period 3 (December) did not differ significantly from other periods, it showed better parameters for the quality of C. macropomum oocytes.O estudo foi conduzido com o objetivo de analisar o comportamento reprodutivo da espécie Colossoma macropomum, quanto à qualidade de seus gametas femininos ao longo da estação reprodutiva. O experimento foi executado em Pimenta Bueno-Rondônia durante a estação reprodutiva do C. macropomum. Utilizaram 36 fêmeas durante a estação de 2010-2011. Cada coleta apresentou um intervalo de 15±5 dias. Através da extrusão foram coletados os gametas femininos e realizadas as seguintes análises ao longo da estação: peso de oócitos liberados (g); índice de produtividade; taxa de fertilização e eclosão. Durante a estação 2010-2011 foi verificado efeito (p < 0,05) de período (coleta) dentro da estação para peso de oócitos, índice de produtividade e taxa de fertilização. Apesar do período 3 (coleta – mês de dezembro) não ter diferenciado significativamente de alguns períodos, foi o que apresentou os melhores parâmetros estabelecidos para a qualidade dos oócitos de C. macropomum
    • …
    corecore