TOI-431/HIP 26013: a super-Earth and a sub-Neptune transiting a bright, early K dwarf, with a third RV planet

Stars and planetary system

TOI-431/HIP 26013: A super-Earth and a sub-Neptune transiting a bright, early K dwarf, with a third RV planet

We present the bright (Vmag = 9.12), multiplanet system TOI-431, characterized with photometry and radial velocities (RVs). We estimate the stellar rotation period to be 30.5 ± 0.7 d using archival photometry and RVs. Transiting Exoplanet Survey Satellite (TESS) objects of Interest (TOI)-431 b is a super-Earth with a period of 0.49 d, a radius of 1.28 ± 0.04 R, a mass of 3.07 ± 0.35 M, and a density of 8.0 ± 1.0 g cm-3; TOI-431 d is a sub-Neptune with a period of 12.46 d, a radius of 3.29 ± 0.09 R, a mass of 9.90+1.53-1.49 M, and a density of 1.36 ± 0.25 g cm-3. We find a third planet, TOI-431 c, in the High Accuracy Radial velocity Planet Searcher RV data, but it is not seen to transit in the TESS light curves. It has an Msin i of 2.83+0.41-0.34 M, and a period of 4.85 d. TOI-431 d likely has an extended atmosphere and is one of the most well-suited TESS discoveries for atmospheric characterization, while the super-Earth TOI-431 b may be a stripped core. These planets straddle the radius gap, presenting an interesting case-study for atmospheric evolution, and TOI-431 b is a prime TESS discovery for the study of rocky planet phase curves

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

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