21 research outputs found

    A gravitationally lensed quasar discovered in OGLE

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    Indexación: Scopus; Web of Science.We report the discovery of a new gravitationally lensed quasar (double) from the Optical Gravitational Lensing Experiment (OGLE) identified inside the ~670deg2 area encompassing the Magellanic Clouds. The source was selected as one of ~60 'red W1-W2' mid-infrared objects from WISE and having a significant amount of variability in OGLE for both two (or more) nearby sources. This is the first detection of a gravitational lens, where the discovery is made 'the other way around', meaning we first measured the time delay between the two lensed quasar images of -132 < tAB < -76 d (90 per cent CL), with the median tAB ~-102 d (in the observer frame), and where the fainter image B lags image A. The system consists of the two quasar images separated by 1.5 arcsec on the sky, with I ~20.0mag and I ~19.6mag, respectively, and a lensing galaxy that becomes detectable as I ~21.5 mag source, 1.0 arcsec from image A, after subtracting the two lensed images. Both quasar images show clear AGN broad emission lines at z=2.16 in the New Technology Telescope spectra. The spectral energy distribution (SED) fitting with the fixed source redshift provided the estimate of the lensing galaxy redshift of z ~0.9 ± 0.2 (90 per cent CL), while its type is more likely to be elliptical (the SED-inferred and lens-model stellar mass is more likely present in ellipticals) than spiral (preferred redshift by the lens model). © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.https://academic.oup.com/mnras/article/476/1/663/483368

    Experimental progress in positronium laser physics

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    Gene silencing: concepts, applications, and perspectives in woody plants

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    The invasive flea beetle Luperomorpha xanthodera (Coleoptera: Chrysomelidae: Alticinae), potentially noxious to ornamental plants - first record in Poland

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    A specimen of a flea beetle collected by plant sweeping from an experimental plot of oregano in Warsaw showed characteristics of the invasive species Luperomorpha xanthodera. This beetle, originating from Far East, appeared in Europe at the beginning of this century and seems to extend its range continuously. So far, it has been noted from England, Italy, France, The Netherlands, Germany, Austria and Hungary but not from Poland. Being polyphagous, adult flea beetles of this species may appear in numbers on flowers of various ornamental plants causing considerable damage

    Gender Classification in Human Gait Using Support Vector Machine

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    Abstract. We describe an automated system that classifies gender by utilising a set of human gait data. The gender classification system consists of three stages: i) detection and extraction of the moving human body and its contour from im-age sequences; ii) extraction of human gait signature by the joint angles and body points; and iii) motion analysis and feature extraction for classifying gen-der in the gait patterns. A sequential set of 2D stick figures is used to represent the gait signature that is primitive data for the feature generation based on mo-tion parameters. Then, an SVM classifier is used to classify gender in the gait patterns. In experiments, higher gender classification performances, which are 96 % for 100 subjects, have been achieved on a considerably larger database.

    Efeitos da poluição por petróleo na estrutura da folha de Podocarpus lambertii Klotzsch ex Endl., Podocarpaceae Effects of oil pollution on leaf structure of Podocarpus lambertii Klotzsch ex Endl., Podocarpaceae

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    Podocarpus lambertii, popularmente conhecida como pinheiro-bravo é uma Podocarpaceae típica da região Sul do Brasil, família que se distingue de outras coníferas por possuir uma estrutura de suporte para o óvulo denominada "epimatium". O presente estudo teve como objetivo investigar, por meio de parâmetros morfológicos e anatômicos, os efeitos da poluição por petróleo na estrutura das folhas de Podocarpus lambertii Klotzsch ex Endl. (Podocarpaceae), popularmente conhecida por pinheiro-bravo. As folhas foram coletadas no município de Araucária, Paraná, Brasil, na Refinaria de petróleo Presidente Getúlio Vargas (REPAR) um ano após exposição à poluição provocada pelo derramamento de petróleo. Esta espécie foi selecionada, porque além de ser nativa, apresentou um comportamento diferenciado dentre as demais diante da poluição. Folhas de nove indivíduos (seis expostos ao petróleo e três controle) foram coletadas. Foram avaliadas em microscopia fotônica as dimensões foliares (comprimento, largura e área foliar), a espessura dos tecidos e a densidade estomática. Os dados obtidos foram analisados estatisticamente. Nos indivíduos expostos à poluição, a superfície foliar foi menor, a densidade estomática e espessura dos tecidos foliares foram maiores quando comparados aos indivíduos controle. Os resultados obtidos permitem concluir que P. lambertti reagiu quando de sua exposição à poluição por petróleo.<br>Podocarpus lambertii, locally known as "pinheiro-bravo", is a typical Podocarpaceae from Southern Brazil. This family is the most diverse of conifers; it has a distinguishing characteristic, namely the presence of an ovule support structure, called an epimatium. The aim of this study was to investigate the effect of oil pollution on the leaf structure of P. lambertii through morphology and anatomy. Leaves were collected in Araucária Municipality, Paraná, Brazil, at the Presidente Getúlio Vargas Petroleum Refinery one year after they had been exposed to pollution by an oil spill. This species was studied because besides being a native species, it behaved differently from the other species when faced with pollution. Nine individuals were selected (six exposed to pollution and three controls). We analyzed the leaf surface (length, width and leaf area), tissue thickness and stomatal density using light microscopy. The data were statistically analyzed. Leaf anatomy was rather variable. The individuals that were exposed to pollution had smaller leaf surfaces, while stomatal density and thickness of leaf tissues were greater when compared to the control
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