11 research outputs found

    Olivine major and trace element compositions coupled with spinel chemistry to unravel the magmatic systems feeding monogenetic basaltic volcanoes

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    Monogenetic basaltic volcanic systems, despite their considerable smaller size and shorter lifetime compared to polygenetic volcanoes, can have complex pre-eruptive histories and composite volcanic facies architectures. Their source-to-surface investigation is essential for our better understanding of monogenetic volcanism and requires high-resolution mineral-scale analyses. In this study, we focus on diversely zoned olivine crystals and their spinel inclusions from alkaline basaltic volcanics that are the result of mixing of numerous magmas, crystals and fragments of various origins. The Fekete-hegy volcanic complex is one of the largest and most composite eruptive centers in the intracontinental monogenetic Bakony‚ÄďBalaton Highland Volcanic Field (western Pannonian Basin, Eastern Central Europe). It is a compound multi-vent system built up by multiple eruption episodes: initial maar-forming phreatomagmatic eruptions were followed by massive lava flows and magmatic explosive activity. We performed stratigraphically controlled sampling in order to reveal the history of the successively erupted magma batches represented by the distinct eruptive units, as well as to discover the petrogenetic processes that controlled the evolution of the magmatic system. The juvenile pyroclasts of the phreatomagmatic eruption products (unit 1) contain a remarkably diverse mineral assemblage including five different olivine types and three distinct spinel groups. In addition, they comprise various xenoliths. Based on detailed textural investigations combined with in situ electron microprobe analyses, high-resolution laser ablation ICP-MS trace element mapping and single spot measurements on the variably zoned olivines of unit 1 samples, eight distinct environments are inferred to have been involved in their formation. Four of these environments account for the significant compositional variation of the olivine-hosted spinel inclusions. A complex set of open- and closed-system petrogenetic processes operated during the evolution of the magmatic system: magma stalling, accumulation, storage, fractionation, mixing, replenishments, cumulate remobilization, incorporation of foreign fragments and crystals from the wall rocks. All these diverse environments and processes resulted in the mixed character of the erupted magmas during the initial phreatomagmatic eruptive phase. In contrast, the uniform petrological features and the small variations shown by the olivines and spinels from unit 2‚Äź‚Äď3 indicate that the later magmatic explosive ‚Äď effusive phase was preceded by a considerable change in the magmatic system; it experienced a simple evolution through olivine + spinel fractional crystallization without any of the complexities seen during the initial phase. The present study emphasizes the importance of high-resolution mineral-scale textural and chemical investigations to unravel the complexity of the sub-volcanic magmatic systems feeding monogenetic basaltic volcanoes. Compared to the application of whole-rock geochemistry alone, this approach enables a direct and more detailed insight into the architecture and evolution of these systems

    The implications of defining obesity as a disease: a report from the Association for the Study of Obesity 2021 annual conference

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    Unlike various countries and organisations, including the World Health Organisation and the European Parliament, the United Kingdom does not formally recognise obesity as a disease. This report presents the discussion on the potential impact of defining obesity as a disease on the patient, the healthcare system, the economy, and the wider society. A group of speakers from a wide range of disciplines came together to debate the topic bringing their knowledge and expertise from backgrounds in medicine, psychology, economics, and politics as well as the experience of people living with obesity. The aim of their debate was not to decide whether obesity should be classified as a disease but rather to explore what the implications of doing so would be, what the gaps in the available data are, as well as to provide up-to-date information on the topic from experts in the field. There were four topics where speakers presented their viewpoints, each one including a question-and-answer section for debate. The first one focused on the impact that the recognition of obesity could have on people living with obesity regarding the change in their behaviour, either positive and empowering or more stigmatising. During the second one, the impact of defining obesity as a disease on the National Health Service and the wider economy was discussed. The primary outcome was the need for more robust data as the one available does not represent the actual cost of obesity. The third topic was related to the policy implications regarding treatment provision, focusing on the public's power to influence policy. Finally, the last issue discussed, included the implications of public health actions, highlighting the importance of the government's actions and private stakeholders. The speakers agreed that no matter where they stand on this debate, the goal is common: to provide a healthcare system that supports and protects the patients, strategies that protect the economy and broader society, and policies that reduce stigma and promote health equity. Many questions are left to be answered regarding how these goals can be achieved. However, this discussion has set a good foundation providing evidence that can be used by the public, clinicians, and policymakers to make that happen

    The global retinoblastoma outcome study : a prospective, cluster-based analysis of 4064 patients from 149 countries

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    DATA SHARING : The study data will become available online once all analyses are complete.BACKGROUND : Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival. METHODS : We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models. FINDINGS : The cohort included 4064 children from 149 countries. The median age at diagnosis was 23¬∑2 months (IQR 11¬∑0‚Äď36¬∑5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0¬∑8%) of 636 children from high-income countries, 55 (5¬∑4%) of 1027 children from upper-middle-income countries, 342 (19¬∑7%) of 1738 children from lower-middle-income countries, and 196 (42¬∑9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98¬∑8%) of 4064 children. The 3-year survival rate was 99¬∑5% (95% CI 98¬∑8‚Äď100¬∑0) for children from high-income countries, 91¬∑2% (89¬∑5‚Äď93¬∑0) for children from upper-middle-income countries, 80¬∑3% (78¬∑3‚Äď82¬∑3) for children from lower-middle-income countries, and 57¬∑3% (52¬∑1-63¬∑0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16¬∑67; 95% CI 4¬∑76‚Äď50¬∑00), cT4 advanced tumour compared to cT1 (8¬∑98; 4¬∑44‚Äď18¬∑18), and older age at diagnosis in children up to 3 years (1¬∑38 per year; 1¬∑23‚Äď1¬∑56). For children aged 3‚Äď7 years, the mortality risk decreased slightly (p=0¬∑0104 for the change in slope). INTERPRETATION : This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.The Queen Elizabeth Diamond Jubilee Trust and the Wellcome Trust.https://www.thelancet.com/journals/langlo/homeam2023Paediatrics and Child Healt

    Tracking plumbing system dynamics at the Campi Flegrei caldera, Italy: high-resolution trace element mapping of the Astroni crystal cargo

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    The Campi Flegrei caldera (southern Italy) is one of the most hazardous volcanic systems on Earth, having produced >60 eruptions in the past 15 ka. The caldera remains active and its potential for future eruptions is high, posing a danger to the dense population living nearby. Despite this, our understanding of pre-eruptive processes and the architecture of the sub-volcanic system are poorly constrained. Here, we combine established petrological techniques, geothermobarometric evaluation, and high-resolution trace element crystal mapping, to present a multifaceted, coherent reconstruction of the complex pre-eruptive dynamics and eruption timescales of Astroni volcano located in the eastern sector of Campi Flegrei caldera. The Astroni volcano is an important case study for investigating plumbing system processes and dynamics at Campi Flegrei caldera because it produced the most recent (ca. 4 ka ago) Plinian eruption within the caldera (Astroni 6); current long-term forecasting studies postulate that a similar sized event in this location is a probable future scenario. Geothermobarometric results indicate interaction between an evolved, shallow magma chamber, and a less evolved, deeper pocket of magma, in agreement with previous studies focused on the Astroni 6 eruption products. In addition, a range of textural and trace element zoning patterns point to a complex evolution of both magmas prior to their subsequent interaction. High-resolution trace element crystal maps reveal discrete zonations in compatible elements. These zonations, combined with knowledge of K-feldspar growth rates, highlight a recharge event in the shallow plumbing system a few hours to days before the Astroni 6 eruption

    Role of magma mixing in the pre-eruptive dynamics of the Aeolian Islands volcanoes (Southern Tyrrhenian Sea, Italy)

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    We combined literature and experimental data to determine the role of magma mixing in the pre-eruptive dynamics of the Aeolian Islands volcanoes. As a first step, we systematically reviewed the evidence supporting the hypothesis of mixing-triggered eruptions in the Aeolian archipelago, providing textural, chemical, and rheological constraints. The existing data highlighted the significant role of magma mixing in many eruptions within the Aeolian archipelago. Examples include the Upper Pollara and Porri volcano eruptions at Salina, Monte Guardia, and the AD 1230 Monte Pilato eruption at Lipari, as well as the present-day activity at Stromboli. Then, we focused on Vulcano Island, chosen as a case study because it represents one of the volcanoes posing the highest risk in the Aeolian archipelago. At Vulcano Island, we highlighted the role of magma mixing in the AD 1739 and 1888‚Äď90 eruptions. Finally, we investigated mixing-to-eruption timescales for the AD 1739 eruption, performing mixing experiments, and evaluated the progressive decay of the chemical concentration variance with time. Results pointed to mixing-to-eruption timescales of the order of 29 ¬Ī 9 h and magma ascent rates ranging between 3√ó10‚ąí2 and 5√ó10‚ąí2 m s‚ąí1. We finally emphasized that the presented results may have significant implications in the context of volcanic hazard mitigation and planning of emergency activities

    Tracking plumbing system dynamics at the Campi Flegrei caldera, Italy: High-resolution trace element mapping of the Astroni crystal cargo

    No full text
    The Campi Flegrei caldera (southern Italy) is one of the most hazardous volcanic systems on Earth, having produced >60 eruptions in the past 15‚ÄĮka. The caldera remains active and its potential for future eruptions is high, posing a danger to the dense population living nearby. Despite this, our understanding of pre-eruptive processes and the architecture of the sub-volcanic system are poorly constrained. Here, we combine established petrological techniques, geothermobarometric evaluation, and high-resolution trace element crystal mapping, to present a multifaceted, coherent reconstruction of the complex pre-eruptive dynamics and eruption timescales of Astroni volcano located in the eastern sector of Campi Flegrei caldera. The Astroni volcano is an important case study for investigating plumbing system processes and dynamics at Campi Flegrei caldera because it produced the most recent (ca. 4‚ÄĮka ago) Plinian eruption within the caldera (Astroni 6); current long-term forecasting studies postulate that a similar sized event in this location is a probable future scenario

    HLA-DR polymorphism in SARS-CoV-2 infection and susceptibility to symptomatic COVID-19

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    SARS-CoV-2 infection results in different outcomes ranging from asymptomatic infection to mild or severe disease and death. Reasons for this diversity of outcome include differences in challenge dose, age, gender, comorbidity and host genomic variation. Human leukocyte antigen (HLA) polymorphisms may influence immune response and disease outcome. We investigated the association of HLAII alleles with case definition symptomatic COVID-19, virus-specific antibody and T-cell immunity. A total of 1364 UK healthcare workers (HCWs) were recruited during the first UK SARS-CoV-2 wave and analysed longitudinally, encompassing regular PCR screening for infection, symptom reporting, imputation of HLAII genotype and analysis for antibody and T-cell responses to nucleoprotein (N) and spike (S). Of 272 (20%) HCW who seroconverted, the presence of HLA-DRB1*13:02 was associated with a 6·7-fold increased risk of case definition symptomatic COVID-19. In terms of immune responsiveness, HLA-DRB1*15:02 was associated with lower nucleocapsid T-cell responses. There was no association between DRB1 alleles and anti-spike antibody titres after two COVID vaccine doses. However, HLA DRB1*15:01 was associated with increased spike T-cell responses following both first and second dose vaccination. Trial registration: NCT04318314 and ISRCTN15677965

    Grand Challenges in global eye health: a global prioritisation process using Delphi method

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    Background: We undertook a Grand Challenges in Global Eye Health prioritisation exercise to identify the key issues that must be addressed to improve eye health in the context of an ageing population, to eliminate persistent inequities in health-care access, and to mitigate widespread resource limitations. Methods: Drawing on methods used in previous Grand Challenges studies, we used a multi-step recruitment strategy to assemble a diverse panel of individuals from a range of disciplines relevant to global eye health from all regions globally to participate in a three-round, online, Delphi-like, prioritisation process to nominate and rank challenges in global eye health. Through this process, we developed both global and regional priority lists. Findings: Between Sept 1 and Dec 12, 2019, 470 individuals complete round 1 of the process, of whom 336 completed all three rounds (round 2 between Feb 26 and March 18, 2020, and round 3 between April 2 and April 25, 2020) 156 (46%) of 336 were women, 180 (54%) were men. The proportion of participants who worked in each region ranged from 104 (31%) in sub-Saharan Africa to 21 (6%) in central Europe, eastern Europe, and in central Asia. Of 85 unique challenges identified after round 1, 16 challenges were prioritised at the global level; six focused on detection and treatment of conditions (cataract, refractive error, glaucoma, diabetic retinopathy, services for children and screening for early detection), two focused on addressing shortages in human resource capacity, five on other health service and policy factors (including strengthening policies, integration, health information systems, and budget allocation), and three on improving access to care and promoting equity. Interpretation: This list of Grand Challenges serves as a starting point for immediate action by funders to guide investment in research and innovation in eye health. It challenges researchers, clinicians, and policy makers to build collaborations to address specific challenges. Funding: The Queen Elizabeth Diamond Jubilee Trust, Moorfields Eye Charity, National Institute for Health Research Moorfields Biomedical Research Centre, Wellcome Trust, Sightsavers, The Fred Hollows Foundation, The Seva Foundation, British Council for the Prevention of Blindness, and Christian Blind Mission. Translations: For the French, Spanish, Chinese, Portuguese, Arabic and Persian translations of the abstract see Supplementary Materials section.</p
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