24 research outputs found

    Sellafield-derived 14C and 129I in the UK West Coast intertidal environment

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    The Sellafield nuclear fuel reprocessing plant, situated on the west coast of the UK, releases both liquid and airborne discharges of radionuclides to the environment. Liquid discharges from Sellafield have been shown to travel up the west coast of the UK and out of the Irish Sea. The focus of this study was to investigate two long-lived radionuclides, 14C and 129I. 14C has a half-life of 5,730 years and is incorporated into the marine carbon cycle where it is readily bioavailable and thus becomes part of the entire food chain. It has a large impact on human populations as, in a global context, the collective dose from 14C, integrated over 10,000 years, comprises about 25% of the collective dose from the complete nuclear fuel cycle. 129I is of radiological importance as it is highly mobile and has a half-life of 15.7 million years. 95% of global anthropogenic 129I is discharged from Sellafield and AREVA NC (La Hague). Recent studies have been undertaken to understand 14C uptake by biota in the Irish Sea and west coast of Scotland but focussed on offshore samples while this study focussed on the intertidal environment. The principle aims of this research were to improve our understanding of the distribution and geochemical behaviour of long-lived Sellafield-derived radionuclides, 14C and 129I, mainly in the organic carbon reservoir of a range of intertidal sites situated between the Irish Sea and the Firth of Lorne, NW Scotland. Specifically, this research has compared the 14C in seaweeds collected from low tide and high tide areas of the intertidal environment, measured the 14C in a range of intertidal biota and measured the 129I in seawater. The main findings of this research were that both 14C and 129I show approximately exponential decreases in activity in the intertidal environment of the west coast of the UK with increasing distance from the Sellafield site. The halving distance for the dispersion of 14C was found to be between 68 km and 89 km while the halving distance for 129I was 64 km. In addition, there is a higher 14C activity in seaweed inhabiting the area of the intertidal environment near the low water mark when compared with seaweed inhabiting the area at the high water mark. It was also found that when seaweed samples from this study were compared to samples collected from 1988/1989, the 14C activities had decreased, despite the fact that the aqueous discharges are now higher, although a large difference in 14C activities was also observed in seaweed samples collected from the same site at different points in time throughout this study. All samples measured were found to have 14C activities above the UK background value (249 ± 1 Bq kg-1 C) and that the organic fraction of biota had predominantly higher 14C activities than the inorganic fraction. When comparing the 14C activity in biota collected from different sites; at Parton, the site closest to Sellafield, a pattern of decreasing activity was found in the biota as follows; seaweed > starfish > mussels > whelks > crabs > winkles ≈ limpets > sea anemones, whereas at Garlieston, the mid-range site, mussels had the highest activity and all other biota sampled were of similar 14C activities while at Port Appin, the site furthest from Sellafield, there was no discernible difference between 14C activities in biota. Finally, there appeared to be a relationship between diet and 14C activity in biota, with biota with a similar diet having similar 14C activities and similar 14C activities between organisms and their food source

    Considerations on Genre and Gender Conventions in Translating from Old English

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    The Old English poem The Wife's Lament is an extremely conventional and, at the same time, original text. It portrays a female character suffering for the absence of her loved one, through the framework of the so-called 'elegiac' style and a mainly heroic vocabulary. The traditional exile theme is, thus, interwoven with the uncommon motif of love sickness. While this appraisal of the poem is the most widely accepted one, disagreement still remains about the translation of some keywords, strictly related to the exile theme, such as sīþ or wræcsīþ. The aim of this paper is to examine diverging readings and glosses of the above mentioned 'exilic/elegiac' keywords, and to show that an accurate translation should not neglect a thorough appraisal of the text in its complexity and the association with related literary patterns and imagery in other poetic and prose texts

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.

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    BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK

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    Background A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. Methods This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. Findings Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. Interpretation ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials

    Refining the Hallstatt plateau: Short-term 14C variability and small scale offsets in 50 consecutive tree-rings from south west Scotland dendro-dated to 410-460 BC

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    Radiocarbon (14C) wiggle-match dating is a technique with a substantial potential to improve the precision of dating timbers in situations where dendrochronology is not tenable. However, one of the key reasons why obtaining a dendrochronological determination might be difficult is the short-lived nature of timbers on a range of archaeological sites, something that also affects the efficiency of the wiggle-match dating technique. Combined with the potential for high expense that the technique presents, it is paramount that wiggle-match dating research design has a good empirical basis. To this end we dated 50 consecutive, individual rings from a timber that grew during the Hallstatt radiocarbon calibration plateau (ca. 750–400 cal BC) in southwest Scotland. The results indicate that (1) the precision and accuracy of wiggle-match dates carried out on short-lived sequences during the Hallstatt plateau may suffer due to insufficient resolution of the calibration data, (2) sampling time-frames roughly equivalent to the underpinning calibration data are recommended (for the period in question this means decadal blocks), and (3) short-lived sequences are at risk of losing accuracy if the actual past trend of radiocarbon diverges from the mean of the radiocarbon calibration curve
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