Métodos de Manejo para Insetos Vetores de Viroses e Broqueadores de Tomate (lycopersicon Esculentum Miller)

O tomateiro, Lycopersicon esculentum é uma solanácea com benefícios socioeconômicos, porém a implantação de sua cultura é considerada de alto risco, devido à ocorrência de importantes pragas, como insetos vetores de viroses e broqueadores de frutos. Portanto, o objetivo deste estudo foi testar a eficiência do uso de armadilhas de cor amarela para captura e melhor densidade de armadilha/plantas para insetos vetores de viroses; testar a associação de diferentes métodos para broqueadores de frutos, tais como o uso de T. pretiosum; bactéria entomopatogênica (Agree); ensacamento de pencas e Manejo Fitossanitário de Pragas, avaliando a infestação de ovos/lagartas de N. elegantalis e de H. zea, bem como de frutos brocados. O monitoramento foi realizado 2 vezes/semana em 1% da cultura e pulverizações com inseticidas químicos ou biológicos realizadas quando atingisse o nível de controle. Os dados foram submetidos ao teste de normalidade Shapiro-Wilk (P≤0,05) e posteriormente submetidos à comparação pelo teste não paramétrico Mann-Whitney (P≤0,05). O uso de armadilhas de cor amarela para insetos vetores de viroses possibilitou uma redução de 90% do custo de aplicação para as safras 2011 e 2012. A melhor densidade foi de 1 armadilha de cor amarela/60 plantas. Para o manejo dos broqueadores o uso de associações reduziu as infestações, pulverizações e número de frutos brocados que podem estar associadas ao correto manejo do tomateiro que com o emprego dessas técnicas propiciou uma redução de inseticidas químicos. Todas as táticas de associações mostraram ter uma maior eficiência, no manejo dos broqueadores de tomate, quando comparados com o convencional. O monitoramento é a peça fundamental no Manejo Fitossanitário de Pragas, pois através dele se conhece o nível populacional das pragas, além de informar se as táticas de manejo estão sendo efetivas ou não. Palavras-chave: Insetos vetores de viroses. Broqueadores de tomate. Lycopersicon esculentum. Métodos alternativo

Rocas volcánicas de la Patagonia: su comportamiento frente a la RAS

En la Patagonia (Argentina) existen gran cantidad de rocas volcánicas que se utilizan como agregados para hormigón. Muchas son potencialmente reactivas frente a los álcalis por contener vidrio volcánico y otras variedades de sílice lábil. En el presente trabajo se estudiaron rocas basálticas y riolíticas de las Prov. de Río Negro y Chubut. Se identificaron como basaltos Huala y Facundo, riolitas Albistur y Camarones (Chubut) y basaltos Pillahuincó compacto y poroso, Meseta de Somún Curá, Ruca Choroi, Cerro Medina, Ing. Jacobacci, Cabecera del Salado, riolita Bienvenida y traquita El Cain (Río Negro). Se aplicó la norma IRAM 1649 para el análisis petrográfico y el método acelerado de la barra de mortero (IRAM 1674). Se concluyó acerca de su potencial reactividad frente a la RAS y se vincularon las causas del comportamiento deletéreo, correlacionando la petrografía, la expansión en las barras de mortero y la incidencia de la sílice disuelta

How Lyman Alpha Emission Depends On Galaxy Stellar Mass

In this work, we show how the stellar mass (M) of galaxies affects the 3<z<4.6 Ly-alpha equivalent width (EW) distribution. To this end, we design a sample of 629 galaxies in the M range 7.6 < logM/Msun < 10.6 from the 3D-HST/CANDELS survey. We perform spectroscopic observations of this sample using the Michigan/Magellan Fiber System, allowing us to measure Ly-alpha fluxes and use 3D-HST/CANDELS ancillary data. In order to study the Ly-alpha EW distribution dependence on M, we split the whole sample in three stellar mass bins. We find that, in all bins, the distribution is best represented by an exponential profile of the form dN(M)/dEW= A(M)exp(-EW/W0(M))/W0(M). Through a Bayesian analysis, we confirm that lower M galaxies have higher Ly-alpha EWs. We also find that the fraction A of galaxies featuring emission and the e-folding scale W0 of the distribution anti- correlate with M, recovering expressions of the forms A(M)= -0.26(.13) logM/Msun+3.01(1.2) and W0(M)= -15.6(3.5) logM/Msun +166(34). These results are crucial for proper interpretation of Ly-alpha emission trends reported in the literature that may be affected by strong M selection biases.Comment: 4 pages, 5 figure

A Giant Protocluster of Galaxies at Redshift 5.7

Galaxy clusters trace the largest structures of the Universe and provide ideal laboratories for studying galaxy evolution and cosmology. Clusters with extended X-ray emission have been discovered at redshifts up to z ~ 2.5. Meanwhile, there has been growing interest in hunting for protoclusters, the progenitors of clusters, at higher redshifts. It is, however, very challenging to find the largest protoclusters at early times when they start to assemble. Here we report a giant protocluster of galaxies at redshift z = 5.7, when the Universe was only one billion years old. This protocluster occupies a volume of about 35x35x35 cubic co-moving megaparsecs. It is embedded in an even larger overdense region with at least 41 spectroscopically confirmed, luminous Lyman-alpha emitting galaxies (Lyman-alpha Emitters, or LAEs), including several previously reported LAEs. Its LAE density is 6.6 times the average density at z ~ 5.7. It is the only one of its kind in an LAE survey in four square degrees on the sky. Such a large structure is also rarely seen in current cosmological simulations. This protocluster will collapse into a galaxy cluster with a mass of (3.6+/-0.9) x 10^{15} solar masses, comparable to those of the most massive clusters or protoclusters known to date.Comment: Published in Nature Astronomy on Oct 15, 2018 (DOI: 10.1038/s41550-018-0587-9

A MegaCam Survey of Outer Halo Satellites. I. Description of the Survey

We describe a deep, systematic imaging study of satellites in the outer halo of the Milky Way. Our sample consists of 58 stellar overdensities --- i.e., substructures classified as either globular clusters, classical dwarf galaxies, or ultra-faint dwarf galaxies --- that are located at Galactocentric distances of R$_{\rm GC}$ > 25 kpc (outer halo) and out to ~400 kpc. This includes 44 objects for which we have acquired deep, wide-field, $g-$ and $r-$band imaging with the MegaCam mosaic cameras on the 3.6m Canada-France-Hawaii Telescope and the 6.5m Magellan-Clay telescope. These data are supplemented by archival imaging, or published $gr$ photometry, for an additional 14 objects, most of which were discovered recently in the Dark Energy Survey (DES). We describe the scientific motivation for our survey, including sample selection, observing strategy, data reduction pipeline, calibration procedures, and the depth and precision of the photometry. The typical 5$\sigma$ point-source limiting magnitudes for our MegaCam imaging --- which collectively covers an area of ~52 deg$^{2}$ --- are $g_{\rm lim}$ ~25.6 and $r_{\rm lim}$ ~25.3 AB mag. These limits are comparable to those from the coadded DES images and are roughly a half-magnitude deeper than will be reached in a single visit with LSST. Our photometric catalog thus provides the deepest and most uniform photometric database of Milky Way satellites available for the foreseeable future. In other papers in this series, we have used these data to explore the blue straggler populations in these objects, their density distributions, star formation histories, scaling relations and possible foreground structures.Comment: Accepted for publication in Ap

A MegaCam Survey of Outer Halo Satellites. III. Photometric and Structural Parameters

We present structural parameters from a wide-field homogeneous imaging survey of Milky Way satellites carried out with the MegaCam imagers on the 3.6m Canada-France-Hawaii Telescope (CFHT) and 6.5m Magellan-Clay telescope. Our survey targets an unbiased sample of "outer halo" satellites (i.e., substructures having Galactocentric distances greater than 25 kpc) and includes classical dSph galaxies, ultra-faint dwarfs, and remote globular clusters. We combine deep, panoramic $gr$ imaging for 44 satellites and archival $gr$ imaging for 14 additional objects (primarily obtained with the DECam instrument as part of the Dark Energy Survey), to measure photometric and structural parameters for 58 outer halo satellites. This is the largest and most uniform analysis of Milky Way satellites undertaken to date and represents roughly three quarters ($58/81 \simeq$72\%) of all known outer halo satellites. We use a maximum-likelihood method to fit four density laws to each object in our survey: exponential, Plummer, King and Sersic models. We examine systematically the isodensity contour maps and color magnitude diagrams for each of our program objects, present a comparison with previous results, and tabulate our best-fit photometric and structural parameters, including ellipticities, position angles, effective radii, Sersic indices, absolute magnitudes, and surface brightness measurements. We investigate the distribution of outer halo satellites in the size-magnitude diagram, and show that the current sample of outer halo substructures spans a wide range in effective radius, luminosity and surface brightness, with little evidence for a clean separation into star cluster and galaxy populations at the faintest luminosities and surface brightnesses.Comment: Accepted for publication in Ap