KELT-21b: A Hot Jupiter Transiting The Rapidly Rotating Metal-Poor Late-A Primary Of A Likely Hierarchical Triple System

We present the discovery of KELT-21b, a hot Jupiter transiting the V = 10.5 A8V star HD 332124. The planet has an orbital period of P = 3.6127647 ± 0.0000033 days and a radius of 1.586 (+0.039)/(-0.040) RJ. We set an upper limit on the planetary mass of MP \u3c 3.91 MJ at 3σ confidence. We confirmed the planetary nature of the transiting companion using this mass limit and Doppler tomographic observations to verify that the companion transits HD 332124. These data also demonstrate that the planetary orbit is well-aligned with the stellar spin, with a sky-projected spin–orbit misalignment of λ = -5.6(+1.7o)/(-1.9). The star has Teff = 7598 (+81)/(-84) K, M* = 1.458 (+0.029)/(-0.028) M⊙, R* = 1.638 ± 0.034 R⊙, and v sin I* = 146 km s⁻¹, the highest projected rotation velocity of any star known to host a transiting hot Jupiter. The star also appears to be somewhat metal poor and α-enhanced, with [Fe/H] = -0.405 (+0.032)/(-0.033) and [α/Fe] = 0.145 ± 0.053; these abundances are unusual, but not extraordinary, for a young star with thin-disk kinematics like KELT-21. High-resolution imaging observations revealed the presence of a pair of stellar companions to KELT-21, located at a separation of 1farcs2 and with a combined contrast of ΔKS = 6.39 ± 0.06 with respect to the primary. Although these companions are most likely physically associated with KELT-21, we cannot confirm this with our current data. If associated, the candidate companions KELT-21 B and C would each have masses of ∼0.12 M⊙, a projected mutual separation of ∼20 au, and a projected separation of ∼500 au from KELT-21. KELT-21b may be one of only a handful of known transiting planets in hierarchical triple stellar systems

Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

Contains fulltext : 172380.pdf (publisher's version ) (Open Access

Benchmarking computational methods to calculate the octanol/water partition coefficients of a diverse set of organic molecules

In the discovery process of new drugs and the development of novel therapies in medicine, computational modeling is a complementary tool for the design of new molecules by predicting for example their solubility in different solvents. Here, we benchmarked several computational methods to calculate the partition coefficients of a diverse set of 161 organic molecules with experimental logP values obtained from the literature. In general, density functional theory methods yielded the best correlations and lower average deviations. Although results are obtained faster with semiempirical and molecular mechanics methodologies, these methods yielded higher average deviations and lower correlation coefficients than hybrid density functional theory methods. We recommend the use of an empirical formula to correct the calculated values with each methodology tested

A Critical Plot Twist: Changing Characters and Foreshadowing the Future of Organizational Storytelling

This review explores the evolution of scholarly research about organizational storytelling over the past 40 years in a sample of 165 papers published between 1975 and 2015. The authors contend that organizational storytelling has established a conventional foothold beside the dominant, scientific narrative of organization studies. Meanwhile, the voice of critical storytelling in organizations has emerged, confirming (and extending) five organizational storytelling themes identified by Rhodes and Brown: sensemaking (and subverting); communicating (and manipulating); change, learning (and challenge); power (and dissent); and identity and identification (and alienation). This review reveals the growing influence of critical management studies, emphasizing the role stories play in disrupting conventional narratives, enriching understanding of present and future storytelling in organizations, and of organizations in general

Hot super-Earths stripped by their host stars.

Simulations predict that hot super-Earth sized exoplanets can have their envelopes stripped by photoevaporation, which would present itself as a lack of these exoplanets. However, this absence in the exoplanet population has escaped a firm detection. Here we demonstrate, using asteroseismology on a sample of exoplanets and exoplanet candidates observed during the Kepler mission that, while there is an abundance of super-Earth sized exoplanets with low incident fluxes, none are found with high incident fluxes. We do not find any exoplanets with radii between 2.2 and 3.8 Earth radii with incident flux above 650 times the incident flux on Earth. This gap in the population of exoplanets is explained by evaporation of volatile elements and thus supports the predictions. The confirmation of a hot-super-Earth desert caused by evaporation will add an important constraint on simulations of planetary systems, since they must be able to reproduce the dearth of close-in super-Earths.peerReviewe