REE mineralisation within the Ditrău Alkaline Complex, Romania: Interplay of magmatic and hydrothermal processes

The Ditrău Igneous Complex (north-east Romania) is a tilted Mesozoic alkaline intrusion (~19 km diameter), with enrichments in rare earth elements (REE), niobium, and molybdenum. It has the potential to contribute to a secure and sustainable European REE mining industry, ensuring supply security for these critical metals. The complex comprises a sequence of ultramafic rocks, alkali gabbros, diorites, syenites, nepheline syenites and alkali granites. These units have been significantly modified by sub-solidus interaction with late-stage magmatic fluids and are cut by secondary mafic dykes. The complex was subsequently cut by REE-mineralised carbonate-rich veins. Geochemical and petrological data, including apatite mineral chemistry, from the alkaline igneous rocks, dykes and veins within the Ditrău Complex, have been used to assess the interplay of magmatic processes with late-stage magmatic and hydrothermal fluids, and the effects of these processes on element remobilisation and concentration of critical metals. Only limited critical metal enrichment was achieved by magmatic processes; the REE were preferentially incorporated into titanite and apatite in ultramafic cumulates during primary crystallisation, and were not enriched in evolved magmas. A hydrothermal system developed within the Ditrău Complex magma chamber during the later stages of magmatic crystallisation, causing localised alteration of nepheline syenites by a sodium-rich fluid. Mafic dykes subsequently acted as conduits for late stage, buoyant potassic fluids, which leached REE and HFSE from the surrounding syenitic rocks. These fluids percolated up and accumulated in the roof zone, causing the breakdown of nepheline to K-rich pseudomorphs and the precipitation of hydrothermal minerals such as zircon and pyrochlore within veins. REE mineralisation within the Ditrău Complex is hosted in the latest hydrothermal phase, mineralised carbonate-rich veins, which cross-cut the complex. Monazite is the main REE-bearing phase, it crystallised from a late REE- and carbonate-rich fluid with pH controlled REE deposition

“Working the System”—British American Tobacco's Influence on the European Union Treaty and Its Implications for Policy: An Analysis of Internal Tobacco Industry Documents

Katherine Smith and colleagues investigate the ways in which British American Tobacco influenced the European Union Treaty so that new EU policies advance the interests of major corporations, including those that produce products damaging to health

Session 17 Ecophysiology

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Todas as criaturas do mundo: a arte dos mapas como elemento de orientação geográfica

Vague in the outlines and abounding in figures of real or fabulous creatures, the iconography of medieval maps played a significant role in helping users to recognize lands that were virtually unknown to Christendom. In a world with no reliable latitudes and longitudes, the land contours, inhabitants and even certain elements of fauna and flora could become variables of utmost importance for geographic orientation. Notwithstanding the higher levels of precision achieved in their efforts to represent geographic space, the considerable advancements made in latitude determination, and their continuous pursuit of a practical method for the establishment of longitudes, the cartographers of the Age of Discoveries still went to the trouble of depicting notable elements - whether real or imaginary - to help travelers get their bearings around different regions of the globe. As the presence of Europeans continued to expand and an authentic scientific revolution took place in the 17th century, the lengthy notes and eye¿catching representations of nature and local inhabitants soon lost their utility as points of reference on 17th-century maps to become mere accessories of aesthetic and commercial value. The advent of the 18th century consolidated, once and for all, the transformation of such illustrations into essentially decorative elements with no other relevant role to play in mapmaking. In addition to decreasing in number, the figures became more stylized and moved to the borders of the maps as ornamental motifs. Although they often maintained some sort of relation with the geographic space depicted on the map, the motifs chosen could also constitute a rather independent element. In fact, allegories, compositions with a variety of mythological figures, and historical representations were often used to underscore the power of certain political agents

Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial

Background Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects. Methods FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762. Findings Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months. Interpretation Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function. Funding UK Stroke Association and NIHR Health Technology Assessment Programme

The SARS-CoV-2 Alpha variant was associated with increased clinical severity of COVID-19 in Scotland: A genomics-based retrospective cohort analysis

Objectives The SARS-CoV-2 Alpha variant was associated with increased transmission relative to other variants present at the time of its emergence and several studies have shown an association between Alpha variant infection and increased hospitalisation and 28-day mortality. However, none have addressed the impact on maximum severity of illness in the general population classified by the level of respiratory support required, or death. We aimed to do this. Methods In this retrospective multi-centre clinical cohort sub-study of the COG-UK consortium, 1475 samples from Scottish hospitalised and community cases collected between 1st November 2020 and 30th January 2021 were sequenced. We matched sequence data to clinical outcomes as the Alpha variant became dominant in Scotland and modelled the association between Alpha variant infection and severe disease using a 4-point scale of maximum severity by 28 days: 1. no respiratory support, 2. supplemental oxygen, 3. ventilation and 4. death. Results Our cumulative generalised linear mixed model analyses found evidence (cumulative odds ratio: 1.40, 95% CI: 1.02, 1.93) of a positive association between increased clinical severity and lineage (Alpha variant versus pre-Alpha variants). Conclusions The Alpha variant was associated with more severe clinical disease in the Scottish population than co-circulating lineages

Microstructural evolution of silicate immiscible liquids in ferrobasalts

An experimental study of the microstructural evolution of an immiscible basaltic emulsion shows that the Fe-rich liquid forms homogeneously nucleated droplets dispersed in a continuous Si-rich liquid, together with droplets heterogeneously nucleated on plagioclase, magnetite, and pyroxene. Heterogeneous nucleation is likely promoted by localised compositional heterogeneities around growing crystals. The wetting angle of Fe-rich droplets on both plagioclase and magnetite increases with decreasing temperature. Droplet coarsening occurs by a combination of diffusion-controlled growth and Ostwald ripening, with an insignificant contribution from coalescence. Characteristic microstructures resulting from the interaction of immiscible Fe-rich liquid with crystal grains during crystal growth can potentially be used as an indicator of liquid unmixing in fully crystallised natural samples. In magma bodies < ~ 10 m in size, gravitationally driven segregation of immiscible Fe-rich droplets is unlikely to be significant. © 2019, The Author(s).Natural Environmental Research Council Doctoral Training Programme studentship project (Grant Ref: NE/L002507/1