Synthetic spectra of H Balmer and HeI absorption lines. I: Stellar library

We present a grid of synthetic profiles of stellar H Balmer and HeI lines at optical wavelengths with a sampling of 0.3 A. The grid spans a range of effective temperature 4000 K < Teff < 50000 K, and gravity 0.0 < log g < 5.0 at solar metallicity. For Teff > 25000 K, NLTE stellar atmosphere models are computed using the code TLUSTY (Hubeny 1988). For cooler stars, Kurucz (1993) LTE models are used to compute thesynthetic spectra. The grid includes the profiles of the high-order hydrogen Balmer series and HeI lines for effective temperatures and gravities that have not been previously synthesized. The behavior of H8 to H13 and HeI 3819 with effective temperature and gravity is very similar to that of the lower terms of the series (e.g. Hb) and the other HeI lines at longer wavelengths; therefore, they are suited for the determination of the atmospheric parameters of stars. These lines are potentially important to make predictions for these stellar absorption features in galaxies with active star formation. Evolutionary synthesis models of these lines for starburst and post-starburst galaxies are presented in a companion paper. The full set of the synthetic stellar spectra is available for retrieval at our website http://www.iaa.es/ae/e2.html and http://www.stsci.edu/science/starburst/ or on request from the authors at [email protected]: To be published in ApJS. 28 pages and 12 figure

Isolamento e identificação de microrganismos endofíticos de mudas de Eucalyptus benthamii para biocontrole de doenças de viveiros.

EVINCI. Resumo

Non-LTE Models and Theoretical Spectra of Accretion Disks in Active Galactic Nuclei

We present self-consistent models of the vertical structure and emergent spectrum of AGN accretion disks. The central object is assumed to be a supermassive Kerr black hole. We demonstrate that NLTE effects and the effects of a self-consistent vertical structure of a disk play a very important role in determining the emergent radiation, and therefore should be taken into account. In particular, NLTE models exhibit a largely diminished H I Lyman discontinuity when compared to LTE models, and the He II discontinuity appears strongly in emission for NLTE models. Consequently, the number of ionizing photons in the He II Lyman continuum predicted by NLTE disk models is by 1 - 2 orders of magnitude higher than that following from the black-body approximation. This prediction has important implications for ionization models of AGN broad line regions, and for models of the intergalactic radiation field and the ionization of helium in the intergalactic medium.Comment: 11 pages; 2 postscript figures; LaTeX, AASPP4 macro; to appear in the Astrophysical Journal (Letters

Re-embedding a 1-Plane Graph into a Straight-line Drawing in Linear Time

Thomassen characterized some 1-plane embedding as the forbidden configuration such that a given 1-plane embedding of a graph is drawable in straight-lines if and only if it does not contain the configuration [C. Thomassen, Rectilinear drawings of graphs, J. Graph Theory, 10(3), 335-341, 1988]. In this paper, we characterize some 1-plane embedding as the forbidden configuration such that a given 1-plane embedding of a graph can be re-embedded into a straight-line drawable 1-plane embedding of the same graph if and only if it does not contain the configuration. Re-embedding of a 1-plane embedding preserves the same set of pairs of crossing edges. We give a linear-time algorithm for finding a straight-line drawable 1-plane re-embedding or the forbidden configuration.Comment: Appears in the Proceedings of the 24th International Symposium on Graph Drawing and Network Visualization (GD 2016). This is an extended abstract. For a full version of this paper, see Hong S-H, Nagamochi H.: Re-embedding a 1-Plane Graph into a Straight-line Drawing in Linear Time, Technical Report TR 2016-002, Department of Applied Mathematics and Physics, Kyoto University (2016

Fungos em acículas da serapilheira de Pinus taeda L. em povoamentos com diferentes idades.

A ação fúngica na decomposição e mineralização da serapilheira em florestas permite a ciclagem de nutrientes, sua produtividade e sustentabilidade. Este estudo avaliou a diversidade dos fungos presentes durante a decomposição de acículas de Pinus taeda sob povoamentos com 6, 10, 14, 17 e 29 anos de idade, em Três Barras, SC, Brasil. Acículas recém-caídas foram coletadas em abril/2006, fragmentadas, submetidas a lavagens sucessivas em água destilada estéril e implantadas em placas de Petri contendo meio BDA mais ácido láctico. Os fungos encontrados pertencem aos gêneros: Aureobasidium, Candida, Cladosporium, Exophiala, Fusarium, Penicillium, Pestalotia, Rhizoctonia, Rhizopus, Trichoderma e Tubercularia. Os gêneros Pestalotia, Trichoderma e Penicillium foram os mais freqüentes. A diversidade fúngica foi maior nos plantios mais velhos e deve garantir o retorno dos nutrientes e a sustentabilidade em rotações mais longas de pínus

Fungos endofíticos em folhas de Erva-mate (Ilex paraguariensis A. St.-Hill.).

Este estudo teve como objetivo analisar o efeito da idade de folhas de erva-mate, colhidas em ervas cultivadas e nativas, sobre a população de fungos endofíticos. Como resultado verificou-se que ocorre uma maior diversidade de fungos endofíticos em folhas adultas de erva-mate do que em folhas jovens. A diversidade foi maior nas plantas nativas, com uma microbiota mais abundante, decorrente de um ambiente sombreado e úmido, mais propício para o seu desenvolvimento, diferente de um agroecossistema. Plantas de erva-mate nativa apresentaram fungos endofíticos de gêneros com potencial de biocontrole que deveriam ser testados quanto à capacidade de induzir proteção contra pragas e doenças.Notas técnicas

Seleção in vitro de fungos endofíticos para o controle biológico de Botrytis cinera em Eucalyptus benthamii.

O Eucalyptus benthamii é uma das principais espécies de eucalipto plantadas na região Sul do Brasil, por sua resistência a geadas e por seu uso na produção florestal de madeira para fins energéticos. Na produção de mudas, uma das principais doenças ocorrentes em viveiros é o mofo-cinzento, causado pelo fungo Botrytis cinerea. Uma das alternativas para o controle dessa doença é o controle biológico com fungos endofíticos, os quais podem competir com os patógenos foliares de mudas de eucalipto. O objetivo deste trabalho foi isolar os fungos endofíticos provenientes de mudas de E. benthamii, identificá-los e selecioná-los para o controle de B. cinerea. Eles foram isolados do interior de tecidos vegetais desinfectados, identificados de acordo com critérios macro e micromorfológicos e classificados a partir de testes de controle biológico in vitro. Os resultados evidenciaram o potencial antagonista dos fungos Aspergillus sp., Penicillium sp. e Trichoderma sp. Nenhum desses fungos causou lesões em mudas de E. benthamii

Flexible Power Modeling of LTE Base Stations

With the explosion of wireless communications in number of users and data rates, the reduction of network power consumption becomes more and more critical. This is especially true for base stations which represent a dominant share of the total power in cellular networks. In order to study power reduction techniques, a convenient power model is required, providing estimates of the power consumption in different scenarios. This paper proposes such a model, accurate but simple to use. It evaluates the base station power consumption for different types of cells supporting the 3GPP LTE standard. It is flexible enough to enable comparisons between state-of-the-art and advanced configurations, and an easy adaptation to various scenarios. The model is based on a combination of base station components and sub-components as well as power scaling rules as functions of the main system parameters

Radiative Transfer in Obliquely Illuminated Accretion Disks

The illumination of an accretion disk around a black hole or neutron star by the central compact object or the disk itself often determines its spectrum, stability, and dynamics. The transport of radiation within the disk is in general a multi-dimensional, non-axisymmetric problem, which is challenging to solve. Here, I present a method of decomposing the radiative transfer equation that describes absorption, emission, and Compton scattering in an obliquely illuminated disk into a set of four one-dimensional transfer equations. I show that the exact calculation of the ionization balance and radiation heating of the accretion disk requires the solution of only one of the one-dimensional equations, which can be solved using existing numerical methods. I present a variant of the Feautrier method for solving the full set of equations, which accounts for the fact that the scattering kernels in the individual transfer equations are not forward-backward symmetric. I then apply this method in calculating the albedo of a cold, geometrically thin accretion disk.Comment: 16 pages, 3 figures; to appear in The Astrophysical Journa

Nucleon-nucleon elastic scattering analysis to 2.5 GeV

A partial-wave analysis of NN elastic scattering data has been completed. This analysis covers an expanded energy range, from threshold to a laboratory kinetic energy of 2.5 GeV, in order to include recent elastic pp scattering data from the EDDA collaboration. The results of both single-energy and energy-dependent analyses are described.Comment: 23 pages of text. Postscript files for the figures are available from ftp://clsaid.phys.vt.edu/pub/said/n