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We modelled ground deformation at Soufrière Hills Volcano (SHV), using data collected by the Montserrat Volcano Observatory from 2010–2019. We investigate the combined use of Electronic Distance Measuring (EDM) and Global Positioning System (GPS) to distinguish shallow from mid-crustal magmatic processes and their surface deformation profiles. Our results suggest that the EDM network responds predominantly to changes in the shallow magmatic system, whereas GPS records variation at mid-crustal levels. In addition, we show that the behaviour of the EDM network, and of the GPS site HERM, can be explained by underpressurisation in a shallow dyke conduit orientated NNW–SSE, while the mid-crustal system was still undergoing pressurisation. The modelled dyke may be responding to magma cooling and contraction associated with a previous intrusion. We find that geodetic monitoring coverage of multiple flanks within 1 km of the vent can improve our understanding of shallow magmatic system processes with asymmetric deformation fields.

Abstract Despite international efforts to limit worker exposure to coal dust, it continues to impact the health of thousands of miners across Europe. Airborne coal dust has been studied to improve risk models and its control to protect workers. Particle size distribution analyses shows that using spraying systems to suppress airborne dusts can reduce particulate matter concentrations and that coals with higher ash yields produce finer dust. There are marked chemical differences between parent coals and relatively coarse deposited dusts (up to 500 µm, DD500). Enrichments in Ca, K, Ba, Se, Pb, Cr, Mo, Ni and especially As, Sn, Cu, Zn and Sb in the finest respirable dust fractions could originate from: (i) mechanical machinery wear; (ii) variations in coal mineralogy; (iii) coal fly ash used in shotcrete, and carbonates used to reduce the risk of explosions. Unusual enrichments in Ca in mine dusts are attributed to the use of such concrete, and elevated K to raised levels of phyllosilicate mineral matter. Sulphur concentrations are higher in the parent coal than in the DD500, probably due to relatively lower levels of organic matter. Mass concentrations of all elements observed in this study remained below occupational exposure limits.

The use of educational technologies in schools is being reshaped by a new kind of intermediary organization that brokers relations between schools, academia, governance, and industry. In this article we define and examine 'edtech brokers' as organizations that operate between the edtech industry, public schools, research centers and governments, guiding schools in the procurement and pedagogical use of edtech. Edtech brokers have remained mostly unexplored despite their potential to redraw the boundaries between public education and the global edtech market. We claim that edtech brokers have become increasingly relevant in the past years, embedding new types of professionalities into education, and taking an active role in co-creating and updating schools' digital infrastructures, the evidence-making mechanisms around edtech, and the pedagogical practices around edtech. The article proposes three distinct categories of edtech brokers -- ambassador, search engine, and data brokers -- and explores their practices of mediation. By doing so, we outline the potential effects that brokers can have on schools and edtech markets, and we disentangle their specific imaginaries of the future of education they promote, often aligned with wider policy desires for reform.