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Development of renewable energy infrastructure requires critical raw materials, such as the rare earth elements (REEs, including scandium) and niobium, and is driving expansion and diversification in their supply chains. Although alternative sources are being explored, the majority of the world’s resources of these elements are found in alkaline-silicate rocks and carbonatites. These magmatic systems also represent major sources of fluorine and phosphorus. Exploration models for critical raw materials are comparatively less well developed than those for major and precious metals, such as iron, copper, and gold, where most of the mineral exploration industry continues to focus. The diversity of lithologic relationships and a complex nomenclature for many alkaline rock types represent further barriers to the exploration and exploitation of REE-high field strength element (HFSE) resources that will facilitate the green revolution. We used a global review of maps, cross sections, and geophysical, geochemical, and petrological observations from alkaline systems to inform our description of the alkaline-silicate REE + HFSE mineral system from continental scale (1,000s km) down to deposit scale (~1 km lateral). Continental-scale targeting criteria include a geodynamic trigger for low-degree mantle melting at high pressure and a mantle source enriched in REEs, volatile elements, and alkalies. At the province and district scales, targeting criteria relate to magmatic-system longevity and the conditions required for extensive fractional crystallization and the residual enrichment of the REEs and HFSEs. A compilation of maps and geophysical data were used to construct an interactive 3-D geologic model (25-km cube) that places mineralization within a depth and horizontal reference frame. It shows typical lithologic relationships surrounding orthomagmatic REE-Nb-Ta-Zr-Hf mineralization in layered agpaitic syenites, roof zone REE-Nb-Ta mineralization, and mineralization of REE-Nb

‘In the mid-1930s, Walter Benjamin posed the question of the relation of art to the dominant representational technology of his time: photography and film. To return to the artwork essay today in the spirit in which it was written is to ask the same question in respect of the hegemonic representational technology of our own time: the digital. Benjamin found that the medium of photography and film had dissolved the auratic quality of art. Digital technology has dissolved the very category of ‘medium’ itself.’ Walter Benjamin’s essay of cultural criticism ‘The Work of Art in the Age of Mechanical Reproduction’ has become a ‘classic’ text, one which resonated through the twentieth century and beyond. In this succinct and pointed new essay, the artist and writer Victor Burgin rereads Benjamin’s 1935 text, to elaborate a new argument contending that the camera today is profoundly imbricated in that which is not visible., https://www.librarystack.org/returning-to-benjamin/?ref=unknown

BACKGROUND Endoscopic treatment of pancreatic necrosis can be challenging and time-consuming because sticky necrotic debris is sometimes difficult to remove. The over-the-scope-grasper, a new tool that has recently become available for this purpose, might also be useful for other indications. However, clinical data on the efficacy and safety of this new device are lacking. AIM To evaluate the technical success and safety of the device in a multicenter setting. METHODS The over-the-scope-grasper was used in nine selected endoscopic centers between November 2020 and October 2021 for appropriate indications. Overall, 56 procedures were included in the study. We retrospectively evaluated procedural parameters of all endoscopic interventions using a predefined questionnaire, with special respect to technical success, indications, duration of intervention, type of sedation, and complications. In the case of pancreatic necrosectomy, the access route, stent type, number of necrosis pieces removed, and clinical handling were also recorded. RESULTS A total of 56 procedures were performed, with an overall technical success rate of 98%. Most of the procedures were endoscopic pancreatic necrosectomies (33 transgastric, 4 transduodenal). In 70% of the procedures, access to the necrotic cavity was established with a lumen apposing metal stent. The technical success of pancreatic necrosectomy was 97%, with a mean of 8 pieces (range, 2-25 pieces) of necrosis removed in a mean procedure time of 59 min (range, 15-120 min). In addition, the device has been used to remove blood clots (n = 6), to clear insufficiency cavities before endoluminal vacuum therapy (n = 5), and to remove foreign bodies from the upper gastrointestinal tract (n = 8). In these cases, the technical success rate was 100%. No moderate or severe/fatal complications were reported in any of the 56 procedures. CONCLUSION These first multicenter data demonstrate that the over-the-scope-grasper is a promising device for en