143 research outputs found

    Correction: Are current guidelines for sun protection optimal for health? Exploring the evidence

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    Correction for ‘Are current guidelines for sun protection optimal for health? Exploring the evidence’ by Robyn M. Lucas et al., Photochem. Photobiol. Sci., 2018, DOI: 10.1039/c7pp00374a

    Controlling the {111}/{110} Surface Ratio of Cuboidal Ceria Nanoparticles

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    The ability to control size and morphology is crucial in optimizing nanoceria catalytic activity as this is governed by the atomistic arrangement of species and structural features at the surfaces. Here, we show that cuboidal cerium oxide nanoparticles can be obtained via microwave-assisted hydrothermal synthesis in highly alkaline media. HRTEM revealed that the cube edges were truncated by CeO2{110} surfaces and the cube corners by CeO2{111} surfaces. When adjusting synthesis conditions by increasing NaOH concentration, the average particle size increased. Although this was accompanied by an increase of the cube faces, CeO2{100}, the cube edges, CeO2{110}, and cube corners, CeO2{111} remained of constant size. Molecular Dynamics (MD) was used to rationalise this behaviour and revealed that energetically, the corners and edges cannot be atomically sharp, rather they are truncated by {111} and {110} surfaces respectively to stabilise the nanocube; both experiment and simulation agreed a minimum size of ~1.6 nm associated with this truncation. Moreover, HRTEM and MD revealed {111}/{110} faceting of the {110} edges, which balances the surface energy associated with the exposed surfaces, which follows {111}>{110}>{100}, although only the {110} surface facets because of the ease of extracting oxygen from its surface, which follows {111}>{100}>{110}. Finally, MD revealed that the {100} surfaces are ‘liquid-like’ with a surface oxygen mobility 5 orders of magnitude higher than that on the {111} surfaces; this arises from the flexibility of the surface species network that can access many different surface arrangements due to very small energy differences. This finding has implications for understanding the surface chemistry of nanoceria and provides avenues to rationalize the design of catalytically active materials at the nanoscale

    The success of the Montreal Protocol in mitigating interactive effects of stratospheric ozone depletion and climate change on the environment

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    The Montreal Protocol and its Amendments have been highly effective in protecting the stratospheric ozone layer, preventing global increases in solar ultraviolet-B radiation (UV-B; 280-315 nm) at Earth's surface, and reducing global warming. While ongoing and projected changes in UV-B radiation and climate still pose a threat to human health, food security, air and water quality, terrestrial and aquatic ecosystems, and construction materials and fabrics, the Montreal Protocol continues to play a critical role in protecting Earth's inhabitants and ecosystems by addressing many of the United Nations Sustainable Development Goals.Non peer reviewe

    United Nations Environment Programme (UNEP), Questions and Answers about the Effects of Ozone Depletion, UV Radiation, and Climate on Humans and the Environment. Supplement of the 2022 Assessment Report of the UNEP Environmental Effects Assessment Panel

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    This collection of Questions & Answers (Q&As) was prepared by the Environmental Effects Assessment Panel (EEAP) of the Montreal Protocol under the umbrella of the United Nations Environment Programme (UNEP). The document complements EEAP’s Quadrennial Assessment 2022 (https://ozone. unep.org/science/assessment/eeap) and provides interesting and useful information for policymakers, the general public, teachers, and scientists, written in an easy-to-understand language

    Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change: UNEP Environmental Effects Assessment Panel, Update 2020

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    This assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595–828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.PWB was supported by the J.H. Mullahy Endowment for Environmental Biology. TMR was partially supported by the University of Helsinki, Faculty of Biological & Environmental Sciences, and by the Academy of Finland (decision #324555). PJN was supported by the Smithsonian Institution. CEW was supported by NSF DEB 1754267, and NSF DEB 1950170. RGZ was supported by the US Environmental Protection Agency—the views expressed in this article are those of the authors and do not necessarily represent the views or policies of the U.S. Environmental Protection Agency. ATB was supported by the Universidad Nacional Autónoma de México and thanks M. en C. Laura Celis for help with literature searches. SH was supported by the Swedish Environmental Protection Agency and Linnaeus University. MAKJ was supported by Science Foundation Ireland (16-IA-4418). JM-A was supported by the Spanish Ministry of Science, Innovation and Universities and European Regional Development Fund (project PGC2018-093824-B-C42). KM was supported by ETH Zurich. LER was supported by the NIHR Manchester Biomedical Research Centre. SAR was supported by the Australian Research Council and the University of Wollongong’s Global Challenges Program. KCR was supported by NSF grants 1754265 and 1761805. Q-WW gratefully acknowledges fnancial support from the CAS Young Talents Program and National Natural Science Foundation of China (41971148). SY was supported by Australian National Health and Medical Research Council CJ Martin Fellowship. We thank Emma Lesley (Global Challenges Program, University of Wollongong, for assistance with Fig. 1)

    Environmental Effects of Stratospheric Ozone Depletion, UV Radiation, and interactions with Climate Change: 2022 Assessment Report

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    The Montreal Protocol on Substances that Deplete the Ozone Layer was established 35 years ago following the 1985 Vienna Convention for protection of the environment and human health against excessive amounts of harmful ultraviolet-B (UV-B, 280-315 nm) radiation reaching the Earth’s surface due to a reduced UV-B-absorbing ozone layer. The Montreal Protocol, ratified globally by all 198 Parties (countries), controls ca 100 ozone-depleting substances (ODS). These substances have been used in many applications, such as in refrigerants, air conditioners, aerosol propellants, fumigants against pests, fire extinguishers, and foam materials. The Montreal Protocol has phased out nearly 99% of ODS, including ODS with high global warming potentials such as chlorofluorocarbons (CFC), thus serving a dual purpose. However, some of the replacements for ODS also have high global warming potentials, for example, the hydrofluorocarbons (HFCs). Several of these replacements have been added to the substances controlled by the Montreal Protocol. The HFCs are now being phased down under the Kigali Amendment. As of December 2022, 145 countries have signed the Kigali Amendment, exemplifying key additional outcomes of the Montreal Protocol, namely, that of also curbing climate warming and stimulating innovations to increase energy efficiency of cooling equipment used industrially as well as domestically. As the concentrations of ODS decline in the upper atmosphere, the stratospheric ozone layer is projected to recover to pre-1980 levels by the middle of the 21st century, assuming full compliance with the control measures of the Montreal Protocol. However, in the coming decades, the ozone layer will be increasingly influenced by emissions of greenhouse gases and ensuing global warming. These trends are highly likely to modify the amount of UV radiation reaching the Earth\u27s surface with implications for the effects on ecosystems and human health. Against this background, four Panels of experts were established in 1988 to support and advise the Parties to the Montreal Protocol with up-to-date information to facilitate decisions for protecting the stratospheric ozone layer. In 1990 the four Panels were consolidated into three, the Scientific Assessment Panel, the Environmental Effects Assessment Panel, and the Technology and Economic Assessment Panel. Every four years, each of the Panels provides their Quadrennial Assessments as well as a Synthesis Report that summarises the key findings of all the Panels. In the in-between years leading up to the quadrennial, the Panels continue to inform the Parties to the Montreal Protocol of new scientific information

    Multitrait genetic association analysis identifies 50 new risk loci for gastro-oesophageal reflux, seven new loci for Barrett’s oesophagus and provides insights into clinical heterogeneity in reflux diagnosis

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    Objective: Gastro-oesophageal reflux disease (GERD) has heterogeneous aetiology primarily attributable to its symptom-based definitions. GERD genome-wide association studies (GWASs) have shown strong genetic overlaps with established risk factors such as obesity and depression. We hypothesised that the shared genetic architecture between GERD and these risk factors can be leveraged to (1) identify new GERD and Barrett's oesophagus (BE) risk loci and (2) explore potentially heterogeneous pathways leading to GERD and oesophageal complications. Design: We applied multitrait GWAS models combining GERD (78 707 cases; 288 734 controls) and genetically correlated traits including education attainment, depression and body mass index. We also used multitrait analysis to identify BE risk loci. Top hits were replicated in 23andMe (462 753 GERD cases, 24 099 BE cases, 1 484 025 controls). We additionally dissected the GERD loci into obesity-driven and depression-driven subgroups. These subgroups were investigated to determine how they relate to tissue-specific gene expression and to risk of serious oesophageal disease (BE and/or oesophageal adenocarcinoma, EA). Results: We identified 88 loci associated with GERD, with 59 replicating in 23andMe after multiple testing corrections. Our BE analysis identified seven novel loci. Additionally we showed that only the obesity-driven GERD loci (but not the depression-driven loci) were associated with genes enriched in oesophageal tissues and successfully predicted BE/EA. Conclusion: Our multitrait model identified many novel risk loci for GERD and BE. We present strong evidence for a genetic underpinning of disease heterogeneity in GERD and show that GERD loci associated with depressive symptoms are not strong predictors of BE/EA relative to obesity-driven GERD loci

    Vitamin D Supplementation to Prevent Acute Respiratory Tract Infections: Systematic Review and Meta-Analysis Of Individual Participant Data

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    OBJECTIVES To assess the overall effect of vitamin D supplementation on risk of acute respiratory tract infection, and to identify factors modifying this effect. DESIGN Systematic review and meta-analysis of individual participant data (IPD) from randomised controlled trials. DATA SOURCES Medline, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, ClinicalTrials.gov, and the International Standard Randomised Controlled Trials Number registry from inception to December 2015. ELIGIBILITY CRITERIA FOR STUDY SELECTION Randomised, double blind, placebo controlled trials of supplementation with vitamin D3 or vitamin D2 of any duration were eligible for inclusion if they had been approved by a research ethics committee and if data on incidence of acute respiratory tract infection were collected prospectively and prespecified as an efficacy outcome. RESULTS 25 eligible randomised controlled trials (total 11 321 participants, aged 0 to 95 years) were identified. IPD were obtained for 10 933 (96.6%) participants. Vitamin D supplementation reduced the risk of acute respiratory tract infection among all participants (adjusted odds ratio 0.88, 95% confidence interval 0.81 to 0.96; P for heterogeneity \u3c0.001). In subgroup analysis, protective effects were seen in those receiving daily or weekly vitamin D without additional bolus doses (adjusted odds ratio 0.81, 0.72 to 0.91) but not in those receiving one or more bolus doses (adjusted odds ratio 0.97, 0.86 to 1.10; P for interaction=0.05). Among those receiving daily or weekly vitamin D, protective effects were stronger in those with baseline 25-hydroxyvitamin D levels \u3c25 nmol/L (adjusted odds ratio 0.30, 0.17 to 0.53) than in those with baseline 25-hydroxyvitamin D levels ≥25 nmol/L (adjusted odds ratio 0.75, 0.60 to 0.95; P for interaction=0.006). Vitamin D did not influence the proportion of participants experiencing at least one serious adverse event (adjusted odds ratio 0.98, 0.80 to 1.20, P=0.83). The body of evidence contributing to these analyses was assessed as being of high quality. CONCLUSIONS Vitamin D supplementation was safe and it protected against acute respiratory tract infection overall. Patients who were very vitamin D deficient and those not receiving bolus doses experienced the most benefit
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