Detailed atmospheric abundance analysis of the optical counterpart of the IR source IRAS 16559-2957

We have undertaken a detailed abundance analysis of the optical counterpart of the IR source IRAS16559-2957 with the aim of confirming its possible post-AGB nature. The star shows solar metallicity and our investigation of a large number of elements including CNO and 12C/13C suggests that this object has experienced the first dredge-up and it is likely still at RGB stage.Comment: 10 pages, 4 figures, 4 tables. To be published by Revista Mexicana de Astronomia y Astrofisica, April 201

Fifteen new species of Sonoma Casey from the eastern United States and a description of the male of Sonoma tolulae (LeConte) (Coleoptera: Staphylinidae: Pselaphinae)

Fifteen new species of faronine pselaphines in the genus Sonoma Casey are described: S. baylessae; S. brasstownensis; S. chouljenkoi; S. cygnus; S. gilae; S. gimmeli; S. holmesi; S. mayori; S. nicholsae; S. parkorum; S. nhunguyeni; S. sokolovi; S. streptophorophallus; S. tishechkini; S. tridens. Male specimens of Sonoma tolulae (LeConte) were collected from the type locality and this species is redescribed. These species bring the total diversity of the genus to 43 species. The genus is divided into four species groups based on characters of the male genitalia. Sonoma corticina Casey was not included in the genus when it was described, thus it cannot be the type species of the genus. We here designate Sonoma tolulae (LeConte) as the type species of the genus Sonoma. A key is provided that will allow discrimination of all eastern species. Life history, habitat, and collection techniques are discussed

Comparison of three collection techniques for capture of Coleoptera, with an emphasis on saproxylic species, in Great Smoky Mountains National Park, USA

Collection methods and/or habitats sampled influence how many and which species are captured during entomological surveys. Here we compare Coleoptera catches among three survey activities, each using a single collection method, at the same study sites in Great Smoky Mountains National Park, USA. Activities included: short-term flight intercept trapping (FITs); sifting/Berlese funneling of leaf litter and extremely decayed downed coarse woody debris; and using emergence chambers containing coarse woody debris of various decay classes. In total, 2472 adult beetle specimens, representing 217 lowest identifiable taxa within 164 genera and 42 families, were collected during the FIT survey. Each survey activity yielded more than 2000 specimens, and a combined total of 413 species was collected. A combination of all surveys yielded the highest species richness when normalized for number of specimens indicating that variation of habitat and/or collection method significantly increases species richness. Of single surveys the FIT survey had the highest absolute species richness (217) and the highest richness when normalized for number of specimens. Species overlap among survey activities was low (Sorensen’s quotient of similarity was 0.20–0.27), which showed that each was about equally dissimilar from all others. Overlap of catch between FITs and emergence chambers was too low to justify substitution of emergence surveys with the FIT survey protocol used when attempting to collect saproxylic Coleoptera

How to enhance crop production and nitrogen fluxes? A result-oriented scheme to evaluate best agri-environmental measures in Veneto Region, Italy

The cost-effectiveness of adopting agri-environmental measures (AEMs) in Europe, which combine agricultural productions with reduced N losses, is debated due to poorly targeted site-specific funding that is allocated regardless of local variability. An integrated DAYCENT model-GIS platform was developed combining pedo-climatic and agricultural systems information. The aim was to evaluate best strategies to improve N fluxes of agro-ecosystems within a perspective of sustainable intensification. Indicators of agronomic efficiency and environmental quality were considered. The results showed that agronomic benefits were observed with a continuous soil cover (conservation agriculture and cover crops), which enhanced nitrogen use efficiency (+17%) and crop yields (+34%), although in some cases these might be overestimated due to modelling limitations. An overall environmental improvement was found with continuous soil cover and long-term change from mineral to organic inputs (NLeach 45 Mg ha 121), which were effective in the sandy soils of western and eastern Veneto with low SOM, improving the soil-water balance and nutrients availability over time. Results suggest that AEM subsidies should be allocated at a site-specific level that includes pedo-climatic variability, following a result-oriented approach

The Momentum Amplituhedron

In this paper we define a new object, the momentum amplituhedron, which is the long sought-after positive geometry for tree-level scattering amplitudes in N = 4 super Yang-Mills theory in spinor helicity space. Inspired by the construction of the ordinary amplituhedron, we introduce bosonized spinor helicity variables to represent our external kinematical data, and restrict them to a particular positive region. The momentum amplituhedron M n,k is then the image of the positive Grassmannian via a map determined by such kinematics. The scattering amplitudes are extracted from the canonical form with logarithmic singularities on the boundaries of this geometry.Peer reviewedFinal Published versio

Modified Debye-Huckel Electron Shielding and Penetration Factor

Screened potential, modified by non standard electron cloud distributions responsible for the shielding effect on fusion of reacting nuclei in astrophysical plasmas, is derived. The case of clouds with depleted tails in space coordinates is discussed. The modified screened potential is obtained both from statistical mechanics arguments based on fluctuations of the inverse of the Debye-Huckel radius and from the solution of a Bernoulli equation used in generalized statistical mechanics. Plots and tables useful in evaluating penetration probability at any energy are provided.Comment: 9 pages, 3 figures, 3 table