3 research outputs found

    An ancient reservoir of volatiles in the Moon sampled by lunar meteorite Northwest Africa 10989

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    Northwest Africa (NWA) 10989 is a recently found lunar meteorite we used to elucidate the history of volatiles (H and Cl) in the Moon through analysis of its phosphates. The petrology, bulk geochemistry and mineralogy of NWA 10989 are consistent with it being a lunar meteorite with intermediate-iron bulk composition, composed of 40% of mare basaltic material and ~ 60% non-mare material, but with no obvious KREEP-rich basaltic components. It is probable that the source region for this meteorite resides near a mare–highlands boundary, possibly on the farside of the Moon. Analyses of chlorine and hydrogen abundances and isotopic composition in apatite and merrillite grains from NWA 10989 indicate sampling of at least two distinct reservoirs of volatiles, one being similar to those for known mare basalts from the Apollo collections, while the other potentially represents a yet unrecognized reservoir. In situ Th-U-Pb dating of phosphates reveal two distinct age clusters with one ranging from 3.98 ± 0.04 to 4.20 ± 0.02 Ga, similar to the ages of cryptomare material, and the other ranging from 3.32 ± 0.01 to 3.96 ± 0.03 Ga, closer to the ages of mare basalts known from the Apollo collections. This lunar breccia features mixing of material, among which a basaltic D-poor volatile reservoir which doesn’t appear to have been recorded by Apollo samples

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

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    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
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