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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]

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The contents of colouring substances in different cultivated varieties of barley (Hordeum vulgare L.) were recorded qualitatively and quantitatively to identify which substances contribute to their colour. HPLC was used to quantify the 3-O-glucosides of the anthocyanidins malvidin, peonidin, pelargonidin, cyanidin and delphinidin. Of the varieties examined, only the ancient spring barley variety 'Weihenstephaner Schwarze Nackte' contained anthocyanins, with delphinidin-3-glucoside accounting for the largest proportion. In addition, another substance was detected, which is most likely also an anthocyanin. The total anthocyanin content was at the upper end of the values previously known from black varieties. MALDI-TOF mass spectrometry was used to try to shed more light on the structure of the dark pigments in the outer layers of the black barley grains. The results suggest that the dark substance is a heterooligomer of different, partly phenolic substances. Specifically, the repeated occurrence of a 180 Da monomer could be detected. Since plant melanins are usually synthesised from the phenolic acids found in the plant, this substance could be caffeic acid and would thus be similar to allomelanin from oats (Avena sativa L.), which is a homooligomer of p-coumaric acid. The development of anthocyanins during malting were recorded photometrically. A clear decrease in the total anthocyanin content could be observed, however, clear weaknesses of the method used to date became apparent. [ABSTRACT FROM AUTHOR]

Purpose: There has been a renewed interest in the repair of the torn anterior cruciate ligament (ACL). Purpose of this study was to evaluate the functional outcome of arthroscopic ACL repair with additional suture augmentation (SA), hypothesizing that isolated ACL ruptures would yield superior patient-reported outcome measures (PROMs) compared to those with concomitant meniscal and/or ligamentous injuries. Methods: This is a retrospective analysis of 93 consecutive patients (67 female, median age 42 years) who underwent arthroscopic ACL repair with SA between January 2017 and March 2019 for an acute traumatic ACL tear confirmed by magnetic resonance imaging (MRI). Patients with pre- or intraoperative mid-substance or distal ACL tears and/or poor tissue quality of the ACL remnant were not considered for ACL repair but were scheduled for an ACL reconstruction with a tendon autograft. In patients who underwent ACL repair with SA, the SA construct was proximally stabilized with a flip-button and distally with a suture anchor. Surgery was preferably performed on the day of injury and all surgeries were performed by the same surgeon. Postoperative rehabilitation included partial weight-bearing (20 kg) for 6 weeks and immobilization in a brace limited at 90-degrees of knee flexion for 4 weeks. Patient-reported outcome measures (PROMs) were determined using International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm Score (LS), Tegner Activity Score (TS) and Forgotten Joint Score (FJS). Knee-laxity was assessed using the KT-1000 arthrometer (Med Metrics Corp. Inc., San Diego, USA). Results: Nine patients underwent revision surgery for a traumatic re-tear (four patients) and chronic instability (five patients) and were excluded from further functional analysis. Functional results of 77 patients (54 female) with a median age of 44 years (IQR 33–51) on the day of surgery were available for follow-up after a median time of 35 months (IQR 33–44). Concomitant injuries were observed in 66 Patients (86%), meniscal injuries in 43 patients (55%) and ligamentous injuries in 50 patients (65%). Median interval from injury to surgery was 1 day (IQR 0–1) with 81% (62/77) of patients being treated within 24 h of injury. The median IKDC was 92 (IQR 86–99), the median LS was 95 (IQR 86–100), the median pre-traumatic TS was 7 (IQR 6–7), the median post-traumatic TS was 6 (IQR 5–7) with a non-significant median difference (TSDiff) of 0 (IQR 0–1). The median FJS was 95 (IQR 78–98). KT-1000 measurements were available in 34 of 77 patients with a median postoperative laxity compared to the uninjured side of 1 mm (IQR 0–2). Interval from injury to surgery, patients' age, body mass index (BMI), knee laxity and concomitant ligamentous or meniscal injuries had no statistically significant impact on postoperative PROMs (n.s.). Conclusion: Following arthroscopic ACL repair with SA good-to-excellent functional results were observed. However, a failure rate of 10% cannot be neglected and warrants further attention. Concomitant injuries to the meniscus and/or collateral ligaments do not seem to be associated with inferior PROMs. Level of evidence: Level IV. [ABSTRACT FROM AUTHOR]