Local AGN Survey (LASr): I. Galaxy sample, infrared colour selection and predictions for AGN within 100 Mpc

To answer major questions on supermassive black hole (SMBH) and galaxy evolution, a complete census of SMBH growth, i.e., active galactic nuclei (AGN), is required. Thanks to all-sky surveys by the Wide-field Infrared Survey Explorer (WISE) and the Spectrum-Roentgen-Gamma (SRG) missions, this task is now feasible in the nearby Universe. We present a new survey, the Local AGN Survey (LASr), with the goal of identifying AGN unbiased against obscuration and determining the intrinsic Compton-thick (CT) fraction. We construct the most complete all-sky galaxy sample within 100 Mpc (90% completeness for log (M*/M⊙) ∼ 9.4), four times deeper than the current reference, the Two Micron All-Sky Survey Redshift Survey (2MRS), which misses ∼20% of known luminous AGN. These 49k galaxies serve as parent sample for LASr, called LASr-GPS. It contains 4.3k already known AGN, ≥82% of these are estimated to have Lnuc(12μm) < 1042.3 erg s−1, i.e., are low-luminosity AGN. As a first method for identifying Seyfert-like AGN, we use WISE-based infrared colours, finding 221 galaxies at Lnuc(12μm) ≥ 1042.3 erg s−1 to host an AGN at 90% reliability. This includes 61 new AGN candidates and implies and optical type 2 fraction of 50–71%. We quantify the efficiency of this technique and estimate the total number of AGN with Lint(2-10  keV) ≥ 1042 erg s−1 in the volume to be 362+145−116 (⁠8.6+3.5−2.8× 10−5 Mpc−3). X-ray brightness estimates indicate the CT fraction to be 40–55% to explain the Swift non-detections of the infrared selected objects. One third of the AGN within 100 Mpc remain to be identified, and we discuss the prospects for the eROSITA all-sky survey to detect them

Variação do número de estômatos e micropêlos em Paspalum vaginatum Sw: em relação às condições abióticas numa marisma do estuário da Lagoa dos Patos, RS-Brasil Variation in the number of stomata and microhairs of Paspalum vaginatum Sw: en relation to abiotic conditions in a breakwater in the Lagoa dos Patos estuary, RS-Brazil

Paspalum vaginatum Sw., gramínea perene, estolonífera, com folhas anfistomáticas e pequenas é característica de pântanos salgados, crescendo em condições estressantes na marisma da lagoa dos Patos, molhe oeste da Barra do Rio Grande, RS. Foram feitas contagens mensais de estômatos e micropêlos nas superfícies adaxial e abaxial das lâminas e relacionadas às características abióticas do ambiente. O número de micropêlos da superfície foliar abaxial variou significativamente e diretamente com a temperatura da água intersticial junto às rizosferas. Estes, porém, não mantiveram correlação com a salinidade intersticial. Os resultados sugerem que a espécie seja uma halófita facultativa. O número de estômatos da superfície abaxial manteve um relacionamento inverso com a pluviosidade. Paspalum vaginatum, apresenta-se como uma espécie com características xeromórficas.<br>Paspalum vaginatum Sw., a perennial, stoloniferous grass with small leaves presenting stomata on both epidermises is characteristic of salt marshes, growing under stressful conditions near the west breakwater of the Rio Grande outlet, Lagoa dos Patos, Rio Grande do Sul, Brazil. Monthly counts of stomata and microhairs on the adaxial and abaxial surfaces were related to the abiotic characteristics of the enviroment. The number of microhairs of the abaxial leaf surface varied significantly and directly with interstitial water temperature close to the rhyzosphere. However, these counts did not correlate with the interstitial salinity. The results suggest that the species is a facultative halophyte. Stomata counts of the abaxial surface showed an inverse relation to precipitation. Paspalum vaginatum appears to be a species with xeromorphic characteristics