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The 2015 VESPA voyage (Volcanic Evolution of South Pacific Arcs) was a seismic and rock dredging expedition to the Loyalty and Three Kings Ridges and South Fiji Basin. In this paper we present 33 40Ar/39Ar, 22 micropaleontological, and two U/Pb ages for igneous and sedimentary rocks from 33 dredge sites in this little‐studied part of the southwest Pacific Ocean. Igneous rocks include basalts, dolerites, basaltic andesites, trachyandesites, and a granite. Successful Ar/Ar dating of altered and/or low‐K basalts was achieved through careful sample selection and processing, detailed petrographic and element mapping of groundmass, and incremental heating experiments on both phenocryst and groundmass separates to interpret the complex spectra produced by samples having multiple K reservoirs. The 40Ar/39Ar ages of most of the sampled lavas, irrespective of composition, are latest Oligocene to earliest Miocene (25–22 Ma); two are Eocene (39–36 Ma). The granite has a U/Pb zircon age of 23.6 ± 0.3 Ma. 40Ar/39Ar lava ages are corroborated by microfossil ages from associated sedimentary rocks. The VESPA lavas are part of a >3,000 km long disrupted belt of Eocene to Miocene subduction‐related volcanic rocks. The belt includes arc rocks in Northland New Zealand, Northland Plateau, Three Kings Ridge, and Loyalty Ridge and, speculatively, D'Entrecasteaux Ridge. This belt is the product of superimposed Eocene and Oligocene‐Miocene remnant volcanic arcs that were stranded along and near the edge of Zealandia while still‐active arc belts migrated east with the Pacific trench. Plain Language Summary: Samples of lava from the seabed between New Zealand and New Caledonia have been dated using atomic clocks and fossils. Most lavas erupted in a big pulse of volcanic activity between 25 and 22 million years ago. They are part of a belt of now‐extinct undersea volcanoes that stretches for more than 3,000 km between New Zealand and the Solomon Islands. These volcanoes were formed by subduction of the Pacific Plate under the Australian Plate. Key Points: A major pulse of 25–22 Ma volcanism is documented on the Loyalty and Three Kings Ridges, southwest Pacific OceanThe ridges are part of a more than 3,000 km long belt of Eocene to Miocene remnant volcanic arcs, stranded along the edge of ZealandiaWith care in sample selection, and petrological work, meaningful Ar/Ar ages can be obtained from altered and/or very low‐K submarine basalts [ABSTRACT FROM AUTHOR]

New age and geochemical data are used to investigate the origin of a ∼670 km-long line of eight seamount volcanoes along the western side of the Norfolk Ridge between New Caledonia and New Zealand. Altered lavas and limestones were dredged from three volcanoes during the 2015 Volcanic Evolution of South Pacific Arcs cruise of N/O l'Atalante, so a total of four, including the northernmost and southernmost, have now been directly sampled and analysed. Dating of lava and volcanic breccia clasts by Ar–Ar methods gives north-to-south ages from these sites of 31.3 ± 0.6, 33 ± 5, 21.5 ± 1.0 and 26.3 ± 0.1 Ma. These ages, along with supporting stratigraphic data on a fifth seamount from IODP borehole U1507, provisionally refute the hypotheses that the seamounts represent a southward-younging, age-progressive, intraplate volcanic chain on the Australian Plate or a subduction-related chain of restricted age range. Geochemically, the upper Eocene to lower Miocene lavas have alkaline and subalkaline basaltic compositions, and some could be shoshonitic. The location of the volcanoes along the western side of the Norfolk Ridge suggests an origin related to late Eocene and early Miocene melting near an intracontinental lithosphere–asthenosphere step. Involvement of a deep slab in petrogenesis is also possible. Eight seamounts form a line along the Norfolk Ridge. Dating and geochemistry indicate the seamount line is not a hotspot track. A rift-related origin, possibly with influence by subduction, is proposed. [ABSTRACT FROM AUTHOR]

Background: British Association of Urological Surgeons (BAUS) published updated guidance on the Enhanced Recovery Programme (ERP) in December 2015 to include avoidance of routine catheterisation and drain insertion in minimally invasive nephrectomy. We changed our practice to ‘catheter-free’ nephrectomy and present a retrospective comparative study of the outcomes in support of this guideline. Aim: The aim of this article is to assess any difference in length of stay (LOS), complications and readmission rates between patients who had catheter-free nephrectomy compared to those who had a catheter inserted as routine peri-operatively. Method: Catheter-free nephrectomy was implemented in May 2014. A retrospective comparative case note review was performed for all eligible patients from January 2013 until May 2015. All partial and radical nephrectomies (laparoscopic or robotic) were included, regardless of pathology. Results: Ninety-two patients were included. Of these, 45 patients had a routine catheter inserted peri-operatively (17 partial, 8 simple, 20 radical), and 47 patients had a catheter-free nephrectomy (22 partial, 2 simple, 23 radical). Mean age difference between groups was non-significant (61.0 vs 60.3 years, p = 0.82). LOS was longer in the catheter group compared to catheter-free group (mean 3.85 vs 2.53 days, median 3 vs 2 days, respectively, p = 0.029). There were 13 complications in the catheter group, two of which were complicated urinary tract infections, causing one readmission. In the catheter-free group there were six postoperative complications and no readmissions; three patients went into acute urinary retention requiring either short-term intermittent self-catheterisation or ‘in/out’ catheterisation. None of these patients were discharged with a catheter. Conclusion: Nephrectomy without routine insertion of a catheter appears to be safe and was associated with a shorter hospital stay and no increase in complications, hence supporting the updated ERP guideline published by BAUS. [ABSTRACT FROM AUTHOR]

New Zealand's isolated position in the Southwest Pacific and the quality of its marine and terrestrial sedimentary record make it a valuable source of information for studies of global climate change. A section at Bryce Burn in Southland, South island, provides a record of middle Miocene global cooling associated with buildup of an extensive semi-permanent ice sheet on antarctica. The section yielded δ18 O, δ13C, lithological, clay mineral, foraminiferal, and pollen data that have been linked to a high-resolution age model based on magnetostratigraphy and foraminiferal dating. The sequence exhibits evidence for a δ18 O c. 0.6‰ positive baseline shift consistent with the age and magnitude of the E3/ Mi3 isotope excursion around 13.9 Ma, carbon maxima 4-6 δ13C C excursions, probable orbitally controlled changes in clay mineralogy, and short-term changes in terrestrial vegetation. This is the first time these stable isotopic events have been recognised in outcrop sequences in New Zealand. There appears to be no clear, long-term shift in the data associated with middle Miocene oceanic cooling, apart from the stable isotope evidence, though Milankovitch-scale, short-term fluctuations are present. [ABSTRACT FROM AUTHOR]

Summary: Elective pelvic lymphadenectomy is one of the enduring controversies in the management of Stage III melanoma of the groin. It can provide valuable staging information but concerns remain over the possibility of increased morbidity without the benefit of increased survival. Endoscopic lymphadenectomy of the pelvic nodes is an established procedure in the management of urological and gynaecological malignancy but is relatively novel in the management of metastatic melanoma. An endoscopic approach reduces the risks suggested to be associated with the open procedure while still providing the clinician with the benefit of improved staging information. The authors present their experience of a combined procedure in a series of eight patients undertaken between January 2005 and May 2006 at the Exeter Melanoma Unit. One patient was discovered to harbour occult pelvic nodal metastases, despite a negative pre-operative CT scan. While no complications were directly attributable to the endoscopic procedure, the only major complication was post-operative lymphoedema which occurred in one case. The authors'' experience suggests a combined procedure is both feasible and safe in the Plastic Surgery Department setting for the management of Stage III melanoma of the groin. This is the first documented UK experience of this technique. [Copyright &y& Elsevier]