The geology and geophysics of Kuiper Belt object (486958) Arrokoth

The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, are primitive objects preserving information about Solar System formation. The New Horizons spacecraft flew past one of these objects, the 36 km long contact binary (486958) Arrokoth (2014 MU69), in January 2019. Images from the flyby show that Arrokoth has no detectable rings, and no satellites (larger than 180 meters diameter) within a radius of 8000 km, and has a lightly-cratered smooth surface with complex geological features, unlike those on previously visited Solar System bodies. The density of impact craters indicates the surface dates from the formation of the Solar System. The two lobes of the contact binary have closely aligned poles and equators, constraining their accretion mechanism

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

An extremely metal-deficient globular cluster in the Andromeda Galaxy

Contains fulltext : 226695.pdf (publisher's version ) (Closed access) Contains fulltext : 226695pre.pdf (Author’s version preprint ) (Closed access

Spectroscopy of globular clusters

New observations of globular clusters in NGC 147 and NGC 6822 were obtained with the HIRES spectrograph on the Keck I telescope on 5 Oct 2015 and 25 Sep 2016. We also include older HIRES observations of four GCs in M33. The spectra are the same as those used by Larsen et al. (2002AJ....124.2615L). In addition to the HIRES observations, we include our previously published VLT/UVES spectra of GCs in the Fornax and WLM galaxies (Larsen et al. 2012A&A...546A..53L, 2014A&A...565A..98L) and we refer to our previous papers for details on the observational strategy and data reduction. These tables contain the individual abundance measurements for each cluster

Spectroscopy of globular clusters

Item does not contain fulltextNew observations of globular clusters in NGC 147 and NGC 6822 were obtained with the HIRES spectrograph on the Keck I telescope on 5 Oct 2015 and 25 Sep 2016. We also include older HIRES observations of four GCs in M33. The spectra are the same as those used by Larsen et al. (2002AJ....124.2615L). In addition to the HIRES observations, we include our previously published VLT/UVES spectra of GCs in the Fornax and WLM galaxies (Larsen et al. 2012A&A...546A..53L, 2014A&A...565A..98L) and we refer to our previous papers for details on the observational strategy and data reduction. These tables contain the individual abundance measurements for each cluster.nul

Globular clusters in the Dwarf Spiral Galaxy NGC 2403

Contains fulltext : 219286.pdf (publisher's version ) (Open Access