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Variations of atmospheric CO 2 during the Pleistocene ice-ages have been associated with changes in the drawdown of carbon into the deep-sea. Modelling studies suggest that about one third of the glacial carbon drawdown may not be associated to the deep ocean, but to the thermocline or intermediate ocean. However, the carbon storage capacity of thermocline waters is still poorly constrained. Here we present paired 230 Th/U and 14 C measurements on scleractinian cold-water corals retrieved from ~ 450 m water depth off the Maldives in the Indian Ocean. Based on these measurements we calculate ∆ 14 C, ∆∆ 14 C and Benthic-Atmosphere (B atm ) ages in order to understand the ventilation dynamics of the equatorial Indian Ocean thermocline during the Last Glacial Maximum (LGM). Our results demonstrate a radiocarbon depleted thermocline as low as -250 to -345‰ (∆∆ 14 C), corresponding to ~ 500–2100 years (B atm ) old waters at the LGM compared to ~ 380 years today. More broadly, we show that thermocline ventilation ages are one order of magnitude more variable than previously thought. Such a radiocarbon depleted thermocline can at least partly be explained by variable abyssal upwelling of deep-water masses with elevated respired carbon concentrations. Our results therefore have implications for radiocarbon-only based age models and imply that upper thermocline waters as shallow as 400 m depth can also contribute to some of the glacial carbon drawdown.

Sedimentological, paleontological, and geochemical data from core XK-1 on the Xisha Islands have allowed for a detailed documentation of the early carbonate development around the Oligocene-Miocene transition in the northern South China Sea (SCS). The deposits within the fore reef, reef, lagoon environments occurred before 23 Ma, the exposure horizon occurred around 23 Ma, and the sediments within the open lagoon setting dominated after 23 Ma. This evolution indicates a sedimentological response to water depth change, which is the combined result of eustatic sea-level fluctuations and tectonic subsidence. The tectonic subsidence during the latest Oligocene and Early Miocene (especially this period) was responsible for the obvious deepening trend. What's more, substantial physical erosion caused an increased amount of terrigenous input into the Xisha Islands area, with detrimental effects on carbonate development after the Oligocene-Miocene boundary. Over the entire South China Sea, the early carbonate systems along the northern and southern margins displayed specific evolution patterns. After comparing these patterns, we found a close relationship between the carbonate initiation and the subduction of the proto-SCS and the opening of the modern SCS. Therefore, it has been demonstrated that sea level and local tectonics as well as paleoclimatic conditions were the main controlling factors in shaping the onset of carbonate sedimentation in the SCS.

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The European research vessel fleet plays a vital role in supporting scientific research and development not just in Europe but also across the globe. This document explores how the fleet has developed since the publication of the European Marine Board Position Paper 10 (EMB PP 10) "European Ocean Research Fleets – Towards a Common Strategy and Enhanced Use" (Binot et al., 2007). It looks at the current fleet and its equipment and capabilities (Chapter 2), the deep sea (Chapter 3) and Polar regions (Chapter 4) as study areas of ever- increasing importance for science and for the vessels that explore them, the role that research vessels play in the wider ocean observing landscape (Chapter 5), the importance of training personnel for research vessels (Chapter 6), and considers management of the European research vessel fleet (Chapter 7). This Position Paper considers what has changed since 2007, what the status is in 2019, and future directions for the European fleet, with a 10-year horizon to 2030. This Position Paper finds that the current European research vessel fleet is highly capable, and is able to provide excellent support to European marine science and wider scientific research and can lead on the world stage. However, with a typical life expectancy of a research vessel of 30 years, the fleet is ageing and urgently requires further investment and reinvestment to continue to be as efficient and capable as the scientific community expects and requires. The capabilities of the fleet have increased considerably since 2007, and vessels have kept up with fast-paced technological developments. The demand for complex and highly capable vessels will continue, and research vessel designs and the fleet as a whole will need to keep pace in order to remain fit-for-purpose and continue to be a key player globally. There is huge diversity in vessel types and designs in terms of capabilities and equipment, management structures and processes, and training possibilities. While

The European research vessel fleet plays a vital role in supporting scientific research and development not just in Europe but also across the globe. This document explores how the fleet has developed since the publication of the European Marine Board Position Paper 10 (EMB PP 10) "European Ocean Research Fleets – Towards a Common Strategy and Enhanced Use" (Binot et al., 2007). It looks at the current fleet and its equipment and capabilities (Chapter 2), the deep sea (Chapter 3) and Polar regions (Chapter 4) as study areas of ever- increasing importance for science and for the vessels that explore them, the role that research vessels play in the wider ocean observing landscape (Chapter 5), the importance of training personnel for research vessels (Chapter 6), and considers management of the European research vessel fleet (Chapter 7). This Position Paper considers what has changed since 2007, what the status is in 2019, and future directions for the European fleet, with a 10-year horizon to 2030. This Position Paper finds that the current European research vessel fleet is highly capable, and is able to provide excellent support to European marine science and wider scientific research and can lead on the world stage. However, with a typical life expectancy of a research vessel of 30 years, the fleet is ageing and urgently requires further investment and reinvestment to continue to be as efficient and capable as the scientific community expects and requires. The capabilities of the fleet have increased considerably since 2007, and vessels have kept up with fast-paced technological developments. The demand for complex and highly capable vessels will continue, and research vessel designs and the fleet as a whole will need to keep pace in order to remain fit-for-purpose and continue to be a key player globally. There is huge diversity in vessel types and designs in terms of capabilities and equipment, management structures and processes, and training possibilities. While

Miocene carbonates of the Eratosthenes Seamount, located offshore from Cyprus in the Eastern Mediterranean (ODP Leg 160, Site 966), have been re-analysed. The use of SEDEX sequential extraction to evaluate the nutrient concentrations and of CT-Scan for the identification of large benthic foraminifera has resulted in a more detailed palaeoenvironmental reconstruction and an improved stratigraphic framework. Three intervals are recognised in the succession and are attributed to the lower, middle and upper Miocene, respectively. The lower Miocene interval is dominated by large benthic foraminifera and echinoids. This association colonized the top of the seamount following its uplift from deep-water to the photic zone. The middle Miocene interval is characterised by rhodoliths and corals at its base and near the top, whereas seagrass/seaweed assemblages (with epiphytic foraminifera and hooked coralline-algal crusts) dominate its central part. The upper Miocene is represented by coral reef facies near its base and lagoonal facies toward its top. The succession was deposited in an oligotrophic environment and exhibits a general shallowing-upward trend that was mainly controlled by tectonic activity related to the northward subduction of the African plate. The succession of the Eratosthenes Seamount is characterised by a diverse large benthic foraminifera assemblage in its lower part and by corals in its uppermost part, whereas corallines characterise the central interval. This trend is common in Miocene Mediterranean carbonates and its occurrence on an isolated seamount confirms its connection with the general evolution of the basin. The decline of miogypsinids and lepidocyclinids after the early Miocene is notable because the Eratosthenes Seamount was geographically close to the Indo-Pacific Ocean where both groups also thrived during the middle Miocene. This decline was probably caused by the early Miocene closure of the deep-water connection between the Indo-Pacific an

The authors regret the mistake in the drawing of the delta drift architecture in figure 11. The authors would like to apologise for any inconvenience caused. [Figure presented]

Large benthic foraminifera are important components of tropical shallow water carbonates. Their structure, developed to host algal symbionts, can be extremely elaborate and presents stratigraphically-significant evolutionary patterns. Therefore their distribution is important in biostratigraphy, especially in the Indo-Pacific area. To provide a reliable age model for two intervals of IODP Hole U1468A from the Maldives Inner-Sea, large benthic foraminifera have been studied with computed tomography. This technique provided 3D models ideal for biometric-based identifications, allowing the upper interval to be placed in the late middle-Miocene and the lower interval in the late Oligocene.

Contains fulltext : 169910.pdf (publisher's version ) (Closed access), Unexplained global developmental delay and epilepsy in childhood pose a major socioeconomic burden. Progress in defining the molecular bases does not often translate into effective treatment. Notable exceptions include certain inborn errors of metabolism amenable to dietary intervention. CAD encodes a multifunctional enzyme involved in de novo pyrimidine biosynthesis. Alternatively, pyrimidines can be recycled from uridine. Exome sequencing in three families identified biallelic CAD mutations in four children with global developmental delay, epileptic encephalopathy, and anaemia with anisopoikilocytosis. Two died aged 4 and 5 years after a neurodegenerative disease course. Supplementation of the two surviving children with oral uridine led to immediate cessation of seizures in both. A 4-year-old female, previously in a minimally conscious state, began to communicate and walk with assistance after 9 weeks of treatment. A 3-year-old female likewise showed developmental progress. Blood smears normalized and anaemia resolved. We establish CAD as a gene confidently implicated in this neurometabolic disorder, characterized by co-occurrence of global developmental delay, dyserythropoietic anaemia and seizures. While the natural disease course can be lethal in early childhood, our findings support the efficacy of uridine supplementation, rendering CAD deficiency a treatable neurometabolic disorder and therefore a potential condition for future (genetic) newborn screening.