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Abstract The automation of ab initio simulations is essential in view of performing high-throughput (HT) computational screenings oriented to the discovery of novel materials with desired physical properties. In this work, we propose algorithms and implementations that are relevant to extend this approach beyond density functional theory (DFT), in order to automate many-body perturbation theory (MBPT) calculations. Notably, an algorithm pursuing the goal of an efficient and robust convergence procedure for GW and BSE simulations is provided, together with its implementation in a fully automated framework. This is accompanied by an automatic GW band interpolation scheme based on maximally localized Wannier functions, aiming at a reduction of the computational burden of quasiparticle band structures while preserving high accuracy. The proposed developments are validated on a set of representative semiconductor and metallic systems.

El Cañón de las Hermosas está ubicado en el centro de Colombia, sobre una de las ramificaciones de la Cordillera de los Andes. Allí se concentraron varios de los síntomas más recurrentes en el diagnóstico del conflicto armado en Colombia: pobreza, desigualdad, precariedad y debilidad institucional, control social y territorial de los grupos armados, disputas por rentas ilegales derivadas del cultivo y tráfico de drogas ilícitas, e impactos sobre la territorialidad y el territorio. En un clima completamente adverso, la propia comunidad ha sido capaz de poner en marcha varios mecanismos de resistencia civil para la protección de la población que han sido reconocidos como plataformas eficaces orientadas al diálogo social y la construcción de paz.

La Unión Europea se relaciona con los países del Cercano Oriente y el Norte de África mediante la Política Europea de Vecindad y la Unión por el Mediterráneo. Estos instrumentos deberían ser una herramienta útil en la consecución de cierta estabilidad y en la promoción de la paz en la región. El análisis realizado en este trabajo pretende demostrar que el interés de la UE en cooperar a la estabilización del conflicto árabe israelí se ha mostrado de manera ambigua resultando en unas relaciones entre la UE e Israel muy limitadas. A su vez, se analiza el papel pasivo de la Unión en la resolución del conflicto, obviando su potencial como mediador diplomático y dejando en manos de EE. UU. la promoción de la paz entre Israel y sus vecinos. Recibido: 13 febrero 2023 Aceptado: 2 junio 2023

The conversion of semimetallic suspended graphene (Gr) to a large-gap semiconducting phase is here realized by controlled adsorption of atomic hydrogen (deuterium) on free-standing nanoporous Gr veils. This approach allows to achieve a very clean and neat adsorption, overcoming any spurious influence associated to the presence of substrates. The effects of local rehybridization from sp2 to sp3 chemical bonding are investigated by combining X-ray photoelectron spectroscopy and high-resolution electron energy-loss spectroscopy (HREELS) with ab-initio based modelling. We find that the hydrogen adatoms on the C sites induce a stretching frequency, clearly identified in the vibrational spectra thanks to the use of the D isotope. Overall, the results are compatible with the predicted fingerprints of adsorption on both sides of Gr corresponding to the graphane configuration. Moreover, HREELS of the deuterated samples shows a sizeable opening of the optical band gap, i.e. 3.25 eV, consistent with the modified spectral density observed in the valence band photoemission. The results are in agreement with ab-initio calculations by GW and Bethe–Salpeter equation approaches, predicting a large quasiparticle gap opening and huge exciton binding energy.

Individuals naturally carry bacteria and other microbes as part of their natural flora, with some being opportunistic pathogens. Approximately 30% of the population is known to carry Staphylococcus aureus in their nasal cavity, an organism that causes infections ranging from soft tissue abscesses to toxic shock syndrome. This problem is compounded by the presence of antibiotic-resistant strains such as Methicillin-Resistant Staphylococcus aureus (MRSA). Commensal bacteria present on cadavers pose a risk to those who handle the body. As a Medical School Anatomy laboratory that performs hands-on cadaveric dissection, we wanted to know whether the embalming process is sufficient to kill all commensal bacteria that pose a risk to staff and students. Even if these strains do not cause disease in these individuals, secondary transmission could occur to friends and family, who may be at higher risk of acquiring an infection. Embalming is assumed to eliminate all microbial contamination on the body. However, there are limited studies to confirm this. This study characterises the incidence of antibiotic sensitive and resistant bacteria in cadavers donated for medical teaching and research. We have screened for Methicillin-Resistant Organisms (MRO) and Extended-Spectrum Beta-Lactamase (ESBL) producing bacteria. In this study group of cadavers, approximately 46% (16/35) carry an MRO, while 51% (18/35) carry an ESBL positive organism prior to embalming. By determining the organisms’ presence pre- and post-embalming, we can evaluate the embalming procedure’s effectiveness. Our results show embalming eliminates detectable microbes in about 51% (18/35) of the cadavers. MRO dropped by 75% (16 to 4 positive cadavers), while ESBL organisms went down by almost 95% (from 18 to 1 positive cadaver). There was a further decrease in the number of positive cadavers after storage at 4 °C to 6% (2/32). Thus, although the embalming process does not immediately sterilise all the cadavers, prolonged storage at 4 °C can further reduce the number of viable bacteria.