Nickel and platinum group metal nanoparticle production by <i>Desulfovibrio alaskensis</i> G20

Desulfovibrio alaskensis G20 is an anaerobic sulfate reducing bacteria. While Desulfovibrio species have previously been shown to reduce palladium and platinum to the zero-state, forming nanoparticles in the process; there have been no reports that D. alaskensis is able to form these nanoparticles. Metal nanoparticles have properties that make them ideal for use in many industrial and medical applications, such as their size and shape giving them higher catalytic activity than the bulk form of the same metal. Nanoparticles of the platinum group metals in particular are highly sought after for their catalytic ability and herein we report the formation of both palladium and platinum nanoparticles by D. alaskensis and the biotransformation of solvated nickel ions to nanoparticle form

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

First Principles Study of the Stability and Diffusion Mechanism of a Carbon Vacancy in the Vicinity of a SiO2/4H‐SiC Interface

We have studied the carbon vacancy in bulk 4H‐SiC and in the vicinity of an SiO /(0001)‐4H‐SiC interface using density functional theory. We find that migration is hindered in the immediate vicinity of the interface, with the energy barrier for diffusion being approximately 15% greater than the same defect in bulk 4H‐SiC. In this paper we show the increased barrier is a consequence of the stabilisation of the vacancy in the immediate interface due to a combination of strengthened reconstructions and interfacial relaxation, coupled with a destabilisation of the transition state structure

Surface-state dependent optical properties of OH-, F-, and H-terminated 4H-SiC quantum dots

Density functional calculations are performed for OH-, F- and H-terminated 4H-SiC 10–20 Å diameter clusters to investigate the effect of surface species upon the optical absorption properties. H-termination results in a pronounced size-dependent quantum-confinement in the absorption, whereas F- and OH-terminations exhibit much reduced size dependent absorption due to surface states. Our findings are in good agreement with recent experimental studies, and are able to explain the little explored dual-feature photoluminescence spectra of SiC quantum dots. We propose that along with controlling the size, suitable surface termination is the key for optimizing optical properties of 4H-SiC quantum structures, such as might be exploited in optoelectronics, photovoltaics and biological applications

Assignment of 13C hyperfine interactions in the P1-center in diamond

Diamond is an attractive material due to its extreme physical properties, and has recently found a key role in the developing field of quantum bits based upon long spin coherence times at room temperature. In both natural and synthetic diamond, nitrogen is probably the dominant impurity, with the simplest configuration being substitution of a host carbon atom, which has a single unpaired electron. This defect, seen as the P1 paramagnetic resonance center, has been the subject of detailed experimental investigation, revealing the extensive interaction of the electron spin with nearby 13C nuclei. The interaction between the electron and nuclear spins is not only of importance in determining defect structure, but is of technological importance, such as in the main decoherence mechanism for NV centers, so understanding the coupling between 13C and the electron spin is of critical importance. In this paper we assess the assignment of hyperfine interactions to the various carbon sites in the vicinity of the nitrogen atom. We show that although the experimentally derived model is correct in the main, the best fit to the calculated data requires reassignment of at least one of the carbon sites