9 research outputs found
Texture and chemistry of pyrite from the Waihi epithermal system, Hauraki Goldfield, New Zealand
The Waihi epithermal system is a low sulfidation epithermal system that hosts one of the largest epithermal Au-Ag deposits in the Southern Hemisphere. Various sulfide minerals are present within the system, including pyrite (FeS2), one of the most abundant sulfide minerals on Earth. Pyrite is an archive for hydrothermal fluid chemistry due to its crystal structure enabling incorporation of other elements such as Co, Ni, Se, As, Te. The presence or absence of these elements reflects the changes in the hydrothermal fluid chemistry throughout the growth of the grain. The textural variations in the grains indicates changes in growth conditions for each grain at the time of formation. The chemistry of each different zone, coupled with stages of growth, indicates the chemical influences on the pyrite in the Waihi system at that time.
The use of petrographic, EPMA and LA-ICPMS analyses demonstrates distinctive textural zones within pyrite grains, varying in chemistry and appearance. Some zones contain elevated concentrations of Au and Ag, and varying concentrations of Cu, Pb or Zn. The textural observations indicate pyrite growth was interrupted by periods of dissolution before the grain continued growing. Most grains begin growth with high trace element concentrations. The lowest concentrations of trace elements occur in the outer growth phase. Inclusions are rich in Pb, Ca, Se, Zn, Au and Ni, and cause the âdirtyâ texture observed in grains. The distinctive textural features are attributed to the varying concentrations in Au, As, Cu, Zn, Ag and Te.
This research showcases the dynamics of hydrothermal fluid flow at Waihi, revealing that the gold-forming hydrothermal system at Waihi are more complex than initially thought. There is both evidence for periods of low gold pyrite growth, and periods of high pyrite growth
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Screening of healthcare workers for SARS-CoV-2 highlights the role of asymptomatic carriage in COVID-19 transmission
Funder: Addenbrooke's Charitable Trust, Cambridge University Hospitals; FundRef: http://dx.doi.org/10.13039/501100002927Significant differences exist in the availability of healthcare worker (HCW) SARS-CoV-2 testing between countries, and existing programmes focus on screening symptomatic rather than asymptomatic staff. Over a 3 week period (April 2020), 1032 asymptomatic HCWs were screened for SARS-CoV-2 in a large UK teaching hospital. Symptomatic staff and symptomatic household contacts were additionally tested. Real-time RT-PCR was used to detect viral RNA from a throat+nose self-swab. 3% of HCWs in the asymptomatic screening group tested positive for SARS-CoV-2. 17/30 (57%) were truly asymptomatic/pauci-symptomatic. 12/30 (40%) had experienced symptoms compatible with coronavirus disease 2019 (COVID-19)>7 days prior to testing, most self-isolating, returning well. Clusters of HCW infection were discovered on two independent wards. Viral genome sequencing showed that the majority of HCWs had the dominant lineage Bâ1. Our data demonstrates the utility of comprehensive screening of HCWs with minimal or no symptoms. This approach will be critical for protecting patients and hospital staff
Stakeholdersâ perspectives on clinical trial acceptability and approach to consent within a limited timeframe: a mixed methods study
Objectives The Bronchiolitis Endotracheal Surfactant Study (BESS) is a randomised controlled trial to determine the efficacy of endo-tracheal surfactant therapy for critically ill infants with bronchiolitis. To explore acceptability of BESS, including approach to consent within a limited time frame, we explored parent and staff experiences of trial involvement in the first two bronchiolitis seasons to inform subsequent trial conduct.Design A mixed-method embedded study involving a site staff survey, questionnaires and interviews with parents approached about BESS.Setting Fourteen UK paediatric intensive care units.Participants Of the 179 parents of children approached to take part in BESS, 75 parents (of 69 children) took part in the embedded study. Of these, 55/69 (78%) completed a questionnaire, and 15/69 (21%) were interviewed. Thirty-eight staff completed a questionnaire.Results Parents and staff found the trial acceptable. All constructs of the Adapted Theoretical Framework of Acceptability were met. Parents viewed surfactant as being low risk and hoped their childâs participation would help others in the future. Although parents supported research without prior consent in studies of time critical interventions, they believed there was sufficient time to consider this trial. Parents recommended that prospective informed consent should continue to be sought for BESS. Many felt that the time between the consent process and intervention being administered took too long and should be âstreamlinedâ to avoid delays in administration of trial interventions. Staff described how the training and trial processes worked well, yet patients were missed due to lack of staff to deliver the intervention, particularly at weekends.Conclusion Parents and staff supported BESS trial and highlighted aspects of the protocol, which should be refined, including a streamlined informed consent process. Findings will be useful to inform proportionate approaches to consent in future paediatric trials where there is a short timeframe for consent discussions.Trial registration number ISRCTN11746266
Abstracts of the 3rd Annual Graduate Entry Research in Medicine Conference
This book contains the abstracts of the papers presented at The 3rd Annual Graduate Entry Research in Medicine Conference (GERMCON 2020) Organized by Warwick Medical School, University of Warwick in collaboration with Swansea University Medical School, Swansea University, Wales, UK held on 12â18 October 2020. This was especially important for Graduate Entry Medical (GEM) students, who have less opportunity and time to engage in research due to their accelerated medical degree.
Conference Title: 3rd Annual Graduate Entry Research in Medicine ConferenceConference Acronym: GERMCON 2020Conference Date: 12â18 October 2020Conference Location:Â Online (Virtual Mode)Conference Organizer: Warwick Medical School, University of Warwick, UKCo-organizer: Swansea University Medical School, Swansea University, Wales, UK
Other Abstract Book of GERMCON: Abstracts of the 4th Annual Graduate Entry Research in Medicine Conferenc