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The subduction zones in the SW Pacific Ocean are some of the most dynamic plate boundaries on Earth with changes in subduction polarity and subduction initiation processes. The New Hebrides island arc formed some 10 million years ago after the Melanesian island arc was abandoned due to the cessation of subduction of the Pacific Plate after collision of oceanic plateaus with the island arc. Parts of the Melanesian island arc occur within the New Hebrides island arc and we show that Miocene volcanic rocks exposed on Malekula island in the New Hebrides island arc consist of island arc tholeiites to alkaline basalts with variable slab contribution. The lava erupted between 22.5 and 16.3 Ma, similar to the Wainimala Group lavas on Fiji representing the eastern portion of the Melanesian island arc. Partial melts from subducted sediments affected a Pacific MORB‐type mantle, but we do not find evidence for a slab component derived from the Ontong Java Plateau or for assimilation of continental crust. Thus, no Miocene subduction of the Ontong Java Plateau occurred beneath Malekula and the basement of the island probably does not consist of continental crust rifted from Australia. The Malekula lava succession resembles that of other portions of the Miocene Melanesian island arc between New Britain and Fiji, indicating continuous subduction of the Pacific plate along this arc. Plain Language Summary: The subduction processes in the SW Pacific Ocean changed polarity some 10 million years ago and little is known about the Melanesian island arc that was active before this time. Volcanic rocks of this Melanesian island arc occur on Malekula island in Vanuatu and these have typical compositions of subduction‐related magmas. The lava erupted between 22.5 and 16.3 Ma, similar to lavas on Fiji representing the eastern portion of the Melanesian island arc. There is no chemical or isotopic evidence for subduction of the Ontong Java Plateau or for assimilation of continental crust. Thus, the basement of the island probably does not consist of continental crust rifted from Australia, which was suggested for the neighboring island. Key Points: Variable lavas formed between 22 and 16 Ma in the Melanesian island arc, probably as small eruptions in an extensional basinMagmas reflect mixing of Pacific‐type mantle with melt from subducted pelagic sediment, but no assimilation of continental crustMalekula lava resemble other magmatic rocks of the Melanesian island arc and isotopes do not show subduction of Ontong Java Plateau material [ABSTRACT FROM AUTHOR]

Although a growing number of nurse practitioners (NPs) are practicing in orthopaedics, little is known about the workforce. The aim of this study was to estimate the size of the orthopaedic NP workforce, compare it with the workforce of primary care NPs, and investigate the interaction effect specialty NP practice and physician relationships have on NP role perception. We selected licensed, practicing orthopaedic and primary care NPs from the 2018 National Sample Survey of Registered Nurses and compared demographics, education, experience, functional autonomy, and job outcomes. Nationally, 2,796 NPs described their specialty as orthopaedics. Compared with primary care NPs, they spent 27% more time on care coordination, were half as likely to have their own patient panel, and were most likely to say that their NP education was fully utilized when in a collaborative relationship with physicians. Differences between orthopaedic and primary care NPs may call for reform of Consensus Model that currently places specialty practice outside its regulatory network., Competing Interests: Neither author has financial, commercial, legal, or professional conflicts of interest that may have influenced this research., (Copyright © 2024 by National Association of Orthopaedic Nurses.)

The southeastern part of New Caledonia main island (Grande Terre) is the location of a large ophiolitic formation that hosts several hyperalkaline springs discharging high pH (∼11) and warm (<40°C) fluids enriched in methane (CH 4 ) and hydrogen (H 2 ). These waters are produced by the serpentinization of the ultrabasic rock formations. Molecular surveys had previously revealed the prokaryotic diversity of some of these New Caledonian springs, especially from the submarine chimneys of Prony Bay hydrothermal field. Here we investigate the microbial community of hyperalkaline waters from on-land springs and their relationships with elevated concentrations of dissolved H 2 (21.1-721.3 μmol/L) and CH 4 (153.0-376.6 μmol/L). 16S rRNA gene analyses (metabarcoding and qPCR) provided evidence of abundant and diverse prokaryotic communities inhabiting hyperalkaline fluids at all the collected springs. The abundance of prokaryotes was positively correlated to the H 2 /CH 4 ratio. Prokaryotes consisted mainly of bacteria that use H 2 as an energy source, such as microaerophilic Hydrogenophaga / Serpentinimonas (detected in all sources on land) or anaerobic sulfate-reducing Desulfonatronum , which were exclusively found in the most reducing (E h ref H 2 ∼ -700 mV) and the most H 2 -enriched waters discharging at the intertidal spring of the Bain des Japonais. The relative abundance of a specific group of uncultured Methanosarcinales that thrive in serpentinization-driven ecosystems emitting H 2 , considered potential H 2 -consuming methanogens, was positively correlated with CH 4 concentrations, and negatively correlated to the relative abundance of methylotrophic Gammaproteobacteria. Firmicutes were also numerous in hyperalkaline waters, and their relative abundance (e.g., Gracilibacter or Dethiobacter ) was proportional to the dissolved H 2 concentrations, but their role in the H 2 budget remains to be assessed. The prokaryotic communities thriving in New Caledonia hyperalkaline waters are similar to those found in other serpentinite-hosted high-pH waters worldwide, such as Lost City (North Atlantic) and The Cedars (California)., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Quéméneur, Mei, Monnin, Postec, Guasco, Jeanpert, Maurizot, Pelletier and Erauso.)

A new approach to the synthesis of the (-)-205B alkaloid is described in this paper. This work is characterised by the development of an efficient chirality transfer through a silyl tethered intramolecular alkylation reaction, an unprecedented tandem highly selective iridium catalyzed partial reduction of lactam coupled with an acid promoted aza-Prins reaction, and an almost complete stereochemical control in Shenvi's radical hydrogen atom transfer on an exocyclic methylene. The second part of this work demonstrates the positive allosteric behavior of this natural alkaloid toward α7 nAChRs, in contrast to the reported inhibitory effect of the unnatural enantiomer.

Hypertriglyceridemia is a well-established cause of acute pancreatitis. Initial treatment for hypertriglyceridemia-induced pancreatitis has consisted of supportive measures; however, triglyceride levels can remain high, causing prolonged organ failure and sepsis. Plasmapheresis has been proposed as a treatment option to effectively reduce triglyceride levels. We present a patient case of hypertriglyceridemia-induced pancreatitis that was treated with standard acute pancreatitis interventions along with plasmapheresis, after which triglyceride levels reduced significantly. Further research is necessary to determine the clinical benefits of plasmapheresis in treating this type of pancreatitis., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

An anaerobic, hydrogenotrophic methane-producing archaeon was isolated from an alkaline thermal spring (42 °C, pH 9.0) in New Caledonia. This methanogen, designated strain CAN T , is alkaliphilic, thermotolerant, with Gram-positive staining non-motile cells. Strain CAN T grows autotrophically using hydrogen exclusively as an energy source and carbon dioxide as the sole carbon source (without the requirement of yeast extract or other organic compounds). It grows at 20-45 °C (optimum, 45 °C) and pH 7.3-9.7 (optimum, pH 9.0). NaCl is not required for growth (optimum 0 %) but is tolerated up to 1.5 %. It resists novobiocin, streptomycin and vancomycin but is inhibited by ampicillin and penicillin, among other antibiotics. The genome consists of a circular chromosome (2.2 Mb) containing 2126 predicted protein-encoding genes with a G+C content of 36.4 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain CAN T is a member of the genus Methanobacterium , most closely related to the alkaliphilic Methanobacterium alcaliphilum WeN4 T with 98.5 % 16S rRNA gene sequence identity. The genomes of strain CAN T and M. alcaliphilum DSM 3459, sequenced in this study, share 71.6 % average nucleotide identity and 14.0 % digital DNA-DNA hybridization. Therefore, phylogenetic and physiological results indicate that strain CAN T represents a novel species, for which the name Methanobacterium alkalithermotolerans sp. nov. is proposed, and strain CAN T (=DSM 102889 T = JCM 31304 T ) is assigned as the type strain.