420 research outputs found

    Continental-scale surface reflectance product from CBERS-4 MUX data: Assessment of atmospheric correction method using coincident Landsat observations

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    A practical atmospheric correction algorithm, called Coupled Moderate Products for Atmospheric Correction (CMPAC), was developed and implemented for the Multispectral Camera (MUX) on-board the China-Brazil Earth Resources Satellite (CBERS-4). This algorithm uses a scene-based processing and sliding window technique to derive MUX surface reflectance (SR) at continental scale. Unlike other optical sensors, MUX instrument imposes constraints for atmospheric correction due to the absence of spectral bands for aerosol estimation from imagery itself. To overcome this limitation, the proposed algorithm performs a further processing of atmospheric products from Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) sensors as input parameters for radiative transfer calculations. The success of CMPAC algorithm was fully assessed and confirmed by comparison of MUX SR data with the Landsat-8 OLI Level-2 and Aerosol Robotic Network (AERONET)-derived SR products. The spectral adjustment was performed to compensate for the differences of relative spectral response between MUX and OLI sensors. The results show that MUX SR values are fairly similar to operational Landsat-8 SR products (mean difference \u3c 0.0062, expressed in reflectance). There is a slight underestimation of MUX SR compared to OLI product (except the NIR band), but the error metrics are typically low and scattered points are around the line 1:1. These results suggest the potential of combining these datasets (MUX and OLI) for quantitative studies. Further, the robust agreement of MUX and AERONET-derived SR values emphasizes the quality of moderate atmospheric products as input parameters in this application, with root-mean-square deviation lower than 0.0047. These findings confirm that (i) CMPAC is a suitable tool for estimating surface reflectance of CBERS MUX data, and (ii) ancillary products support the application of atmospheric correction by filling the gap of atmospheric information. The uncertainties of atmospheric products, negligence of the bidirectional effects, and two aerosol models were also identified as a limitation. Finally, this study presents a framework basis for atmospheric correction of CBERS-4 MUX images. The utility of CBERS data comes from its use, and this new product enables the quantitative remote sensing for land monitoring and environmental assessment at 20 m spatial resolution

    Evaluation of the matrix of plaster with incorporation of rubber of tires for use in construction

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    [EN] The use of gypsum in the Brazilian construction industry has been growing steadily in recent years, when the drywall system started to be used in the internal seals of all types of buildings. The new use this should be added the traditional use of gypsum as coating material applied directly on walls and ceilings and as casting material. Given the above, this paper studies some physical characteristics of gypsum composites produced with the addition of tire rubber residues. The experimental program included the completion of the following tests: mass density in plastic and hardened state, tensile strength in bending, compressive strength, tensile strength in bending, ultrasound and scanning electron microscopy (SEM). The incorporation of crumb rubber content was 5% and 10% relative to the mass of gypsum. Two different tire rubber particle sizes were used: a thin called (#0.075 mm) and thick (# 2.38 mm). The results provide a reduction in the bulk density value. It was found that the adhesion of the rubber particles in the gypsum matrix does not present satisfactory results in coarse. This adhesion deficiency, found in SEM testing, was responsible for the lower flexural strength, tensile strength in bending and compression in plaster composites with coarse when compared to the results of composites with fine grain. With respect to ultrasound testing, it was found that the rubber delays sound propagation time. Lastly, the technical feasibility of the study was tested by means of test specimens, which proved to be efficient.[PT] O uso do gesso na construção civil brasileira vem crescendo continuamente nos Ășltimos anos, quando o sistema drywall passou a ser utilizado nas vedaçÔes internas de todos os tipos de edificaçÔes. A essa utilização nova somam-se os usos tradicionais do gesso como material de revestimento e como material de fundição. Diante do exposto, este trabalho estuda algumas caracterĂ­sticas fĂ­sicas de compĂłsitos de gesso produzidos com a incorporação de resĂ­duos de borracha de pneus. No programa experimental foram realizados os seguintes ensaios: densidade de massa no estado plĂĄstico e endurecido, resistĂȘncia Ă  ruptura na flexĂŁo, resistĂȘncia Ă  compressĂŁo, resistĂȘncia Ă  tração na flexĂŁo, ultrassom e microscopia eletrĂŽnica de varredura (MEV). O teor de incorporação da borracha de pneus foi de 5% e 10% em relação Ă  massa de gesso. Duas diferentes granulometrias de borracha foram utilizadas: a denominada fina (#0,075 mm) e a grossa (#2,38 mm). Os resultados proporcionaram uma redução no valor da densidade de massa. Identificou-se que a aderĂȘncia das partĂ­culas de borracha na matriz de gesso nĂŁo apresenta resultados satisfatĂłrios na granulometria grossa. Esta deficiĂȘncia de aderĂȘncia, constatada na MEV, foi responsĂĄvel pela menor resistĂȘncia Ă  flexĂŁo, Ă  tração na flexĂŁo e Ă  compressĂŁo nos compĂłsitos com a granulometria grossa, quando comparados aos resultados dos compĂłsitos com a granulometria fina. Com relação aos ensaios de ultrassom, constatou-se que a borracha retarda o tempo de propagação do som. Por fim, a viabilidade tĂ©cnica do estudo foi testada por meio de corpos de prova, onde se mostrou ser eficiente.À agĂȘncia de fomento FAPESP – Fundação de Amparo Ă  Pesquisa do Estado de SĂŁo Paulo, pelo auxĂ­lio financeiro.Pinto, N.; Fioriti, C.; Paya Bernabeu, JJ.; Akasaki, JL. (2016). Avaliação de matriz de gesso com incorporação de borracha de pneus para utilização na construção civil. Revista TecnolĂłgica. 25(1):103-117. https://doi.org/10.4025/revtecnol.v25i1.29894S10311725

    C7a, a Biphosphinic Cyclopalladated Compound, Efficiently Controls the Development of a Patient-Derived Xenograft Model of Adult T Cell Leukemia/Lymphoma

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    Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive disease that occurs in individuals infected with the human T lymphotropic virus type 1 (HTLV-1). Patients with aggressive ATLL have a poor prognosis because the leukemic cells are resistant to conventional chemotherapy. We have investigated the therapeutic efficacy of a biphosphinic cyclopalladated complex {Pd2 [S(−)C2, N-dmpa]2 (ÎŒ-dppe)Cl2}, termed C7a, in a patient-derived xenograft model of ATLL, and investigated the mechanism of C7a action in HTLV-1-positive and negative transformed T cell lines in vitro. In vivo survival studies in immunocompromised mice inoculated with human RV-ATL cells and intraperitoneally treated with C7a led to significantly increased survival of the treated mice. We investigated the mechanism of C7a activity in vitro and found that it induced mitochondrial release of cytochrome c, caspase activation, nuclear condensation and DNA degradation. These results suggest that C7a triggers apoptotic cell death in both HTLV-1 infected and uninfected human transformed T-cell lines. Significantly, C7a was not cytotoxic to peripheral blood mononuclear cells (PBMC) from healthy donors and HTLV-1-infected individuals. C7a inhibited more than 60% of the ex vivo spontaneous proliferation of PBMC from HTLV-1-infected individuals. These results support a potential therapeutic role for C7a in both ATLL and HTLV-1-negative T-cell lymphomas

    Photoinduced antibacterial activity of the essential oils from Eugenia brasiliensis lam and Piper mosenii C. DC. by blue led light

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    The objective of this work was to evaluate the phytochemical composition and the antibacterial and antibiotic-modulating activities of the essential oils of Eugenia brasiliensis Lam (OEEb) and Piper mosenii C. DC (OEPm) singly or in association with blue LED (Light-emitting diode) light. The antibacterial and antibiotic-modulatory activities of the essential oils on the activity of aminoglycosides were evaluated to determine the minimum inhibitory concentration (MIC, \u3bcg/mL) in the presence or absence of exposure to blue LED light. The chemical analysis showed \u3b1-pinene and bicyclogermacrene as major constituents of OEPm, whereas \u3b1-muurolol was the main compound of OEEb. Both OEEb and OEPm showed MIC 65 512 \u3bcg/mL against the strains under study. However, the association of these oils with the blue LED light enhanced the action of the aminoglycosides amikacin and gentamicin. In conclusion, the association of aminoglycosides with the blue LED light and essential oils was effective against resistant bacteria

    High Altitude test of RPCs for the ARGO-YBJ experiment

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    A 50 m**2 RPC carpet was operated at the YangBaJing Cosmic Ray Laboratory (Tibet) located 4300 m a.s.l. The performance of RPCs in detecting Extensive Air Showers was studied. Efficiency and time resolution measurements at the pressure and temperature conditions typical of high mountain laboratories, are reported.Comment: 16 pages, 10 figures, submitted to Nucl. Instr. Met

    Networking and Participatory Research Promoting Quality of Life and Well-Being in Portuguese-Speaking African Countries

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    Spread across the planet each human being, individually or in community, aspires for well-being and quality of life, according to the ideal of each one. However, we all believe that there are always ways to live better. For many people the measurement of a better life translates into the guarantee of social rights, the right to basic services, good land, seed and sufficient nutritious food for their community members. The Mechanism to Facilitate the Participation of Universities in the Food and Nutrition Security Council of the Community of Portuguese Speaking Countries is a cooperative academic network fomented by the Community of Portuguese Speaking Countries (CPLP) with support from the Food and Agriculture Organization of the United Nations. This mechanism works with teaching, research and extension in the CPLP Food and Nutrition Security Strategy. The pillars of CPLP Strategy are the strengthening of the governance of public policies on Food and Nutrition Security at all levels of government, social protection based on guaranteeing access to food and family farming with a strategy to increase the availability of good quality food, promoting social and environmental sustainability. CPLP University Mechanism has provided training processes for technicians who work in public policies for Food and Nutrition Security and has contributed to the strengthening of postgraduate programs in Portuguese-speaking African countries. As consequence, it has favored participatory research and mixed methods as a theoretical methodological approach. Therefore, it seeks to focus on the territories of Food and Nutrition Security practices to transform reality, as recommended by CPLP Strategy, however, with the autonomous assumptions of the collaborative network. This chapter presents how local researchers perceive the results of a process of inducing an academic network to transform the local reality and promote Food and Nutrition Security in the context of the CPLP

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

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    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio
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