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Aims: There is considerable controversy regarding optimal management of patients with paraesophageal hiatus hernia (pHH). This survey aims at identifying recommended strategies for work-up, surgical therapy, and postoperative follow-up using Delphi methodology. Methods: We conducted a 2-round, 33-question, web-based Delphi survey on perioperative management (preoperative work-up, surgical procedure and follow-up) of non-revisional, elective pHH among European surgeons with expertise in upper-GI. Responses were graded on a 5-point Likert scale and analyzed using descriptive statistics. Items from the questionnaire were defined as “recommended” or “discouraged” if positive or negative concordance among participants was > 75%. Items with lower concordance levels were labelled “acceptable” (neither recommended nor discouraged). Results: Seventy-two surgeons with a median (IQR) experience of 23 (14–30) years from 17 European countries participated (response rate 60%). The annual median (IQR) individual and institutional caseload was 25 (15–36) and 40 (28–60) pHH-surgeries, respectively. After Delphi round 2, “recommended” strategies were defined for preoperative work-up (endoscopy), indication for surgery (typical symptoms and/or chronic anemia), surgical dissection (hernia sac dissection and resection, preservation of the vagal nerves, crural fascia and pleura, resection of retrocardial lipoma) and reconstruction (posterior crurorrhaphy with single stitches, lower esophageal sphincter augmentation (Nissen or Toupet), and postoperative follow-up (contrast radiography). In addition, we identified “discouraged” strategies for preoperative work-up (endosonography), and surgical reconstruction (crurorrhaphy with running sutures, tension-free hiatus repair with mesh only). In contrast, many items from the questionnaire including most details of mesh augmentation (indication, material, shape, placement, and fixation technique) were “acceptable”. Conclusions: This multinatio

The ages of sedimentation and copper-silver mineralisation in the late Meso- to Neoproterozoic Kalahari Copperbelt, an economically significant copper province, have previously been poorly constrained within a c.600 m.y. period that spans the Neoproterozoic from the assembly and breakup of Rodinia to the assembly of Gondwana. Rhenium-osmium geochronology of molybdenite and copper sulphide minerals and U-Th-Pb laser ablation split-stream inductively coupled plasma-mass spectrometry (LASS ICP-MS) analysis of xenotime grains are utilised to provide absolute and relative age data on the host rocks and mineralising events within the Ghanzi Ridge region of the Kalahari Copperbelt. The data reveal a prolonged history of events, which is partially comparable with depositional and mineralising events in the neighbouring Central African Copperbelt. Together, the earliest Neoproterozoic Re-Os molybdenite and U-Th-Pb xenotime ages provide both a minimum depositional age constraint for the lowermost D’Kar Formation and clear evidence that diagenetic hydrothermal mineralising events took place within the Ghanzi basin. The latest Neoproterozoic to Cambrian Re-Os and U-Th-Pb ages indicate that hydrothermal copper-silver mineralising events occurred during the Pan-African (ca. 600–480 Ma) fold-thrust evolution of the Ghanzi-Chobe zone and were broadly synchronous with widespread epigenetic hydrothermal copper-cobalt mineralising events in the adjacent Central African Copperbelt., The ages of sedimentation and copper-silver mineralisation in the late Meso- to Neoproterozoic Kalahari Copperbelt, an economically significant copper province, have previously been poorly constrained within a c.600 m.y. period that spans the Neoproterozoic from the assembly and breakup of Rodinia to the assembly of Gondwana. Rhenium-osmium geochronology of molybdenite and copper sulphide minerals and U-Th-Pb laser ablation split-stream inductively coupled plasma-mass spectrometry (LASS ICP-MS) analysis of xenotime grains are utilised to provide absolute and relative age data on the host rocks and mineralising events within the Ghanzi Ridge region of the Kalahari Copperbelt. The data reveal a prolonged history of events, which is partially comparable with depositional and mineralising events in the neighbouring Central African Copperbelt. Together, the earliest Neoproterozoic Re-Os molybdenite and U-Th-Pb xenotime ages provide both a minimum depositional age constraint for the lowermost D’Kar Formation and clear evidence that diagenetic hydrothermal mineralising events took place within the Ghanzi basin. The latest Neoproterozoic to Cambrian Re-Os and U-Th-Pb ages indicate that hydrothermal copper-silver mineralising events occurred during the Pan-African (ca. 600–480 Ma) fold-thrust evolution of the Ghanzi-Chobe zone and were broadly synchronous with widespread epigenetic hydrothermal copper-cobalt mineralising events in the adjacent Central African Copperbelt.

The temporal coincidence between the Late Permian mass extinction (LPME) and the emplacement of Siberian Trap basalts suggests a causal link between the two events. Here, we discuss stratigraphic changes of organic and inorganic (including isotopic) geochemical properties of marine sediments across the Permian–Triassic boundary (PTB) in the Hovea-3 core, Western Australia, a key PTB section in the southern Neo-Tethys ocean. These data are compared with published data from the Meishan section, southern China, and from the Opal Creek section in western Canada, providing a view of Tethys and Panthalassa changes at the PTB. Trace metal and N-isotopic data, together with organic matter properties suggest that anoxic conditions were established prior to the LPME, intensified close to the LPME, and continued with photic-zone euxinia into the Early Triassic. For the Hovea-3 section, Re-Os ages confirm Changhsingian (253.5 ± 1.4 Ma) deposition of the dated interval sampled immediately below the stratigraphic level characterized by major lithological and isotopic changes. Evaluation of Re-Os, N, and Hg elemental and isotopic data for Hovea-3 suggests that anoxic conditions in the latest Permian were generally unrelated to direct magmatic contributions. A major increase in the initial Os isotopic ratio of Lower Triassic shales suggest an ~8× increase in the Early Triassic continental runoff, based on moderately conservative assumptions for end-members contributing Os to the Permian–Triassic ocean. Comparison to other PTB sections confirms a global signal of increasing Re/Os ratios in the Late Permian, and major and long-lived changes in the isotopic composition of the post-extinction ocean. A distinct peak in Hg concentrations carrying a volcanic isotopic signature, also identified in other PTB sections, likely represents a major pulse of Siberian Trap volcanism. This Hg peak in the Hovea-3 section, however, is detected above the stratigraphic level containing multiple other w