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Since the 1990s the Mekong River delta has suffered a large decline in sediment supply causing coastal erosion, following catchment disturbance through hydropower dam construction and sand extraction. However, our new geological reconstruction of 2500-years of delta shoreline changes show that serious coastal erosion actually started much earlier. Data shows the sandy coast bounding river mouths accreted consistently at a rate of +2 to +4 km 2 /year. In contrast, we identified a variable accretion rate of the muddy deltaic protrusion at Camau; it was < +1 km 2 /year before 1400 years ago but increased drastically around 600 years ago, forming the entire Camau Peninsula. This high level of mud supply had sharply declined by the early 20th century after a vast canal network was built on the delta. Since then the Peninsula has been eroding, promoted by the conjunction of mud sequestration in the delta plain driven by expansion of rice cultivation, and hysteresis of long-term muddy sedimentation that left the protrusion exposed to wave erosion. Natural mitigation would require substantial increases in sediment supply well above the pre-1990s levels.

The African Middle Stone Age (MSA, typically considered to span ca. 300–30 thousand years ago [ka]), represents our species’ first and longest lasting cultural phase. Although the MSA to Later Stone Age (LSA) transition is known to have had a degree of spatial and temporal variability, recent studies have implied that in some regions, the MSA persisted well beyond 30 ka. Here we report two new sites in Senegal that date the end of the MSA to around 11 ka, the youngest yet documented MSA in Africa. This shows that this cultural phase persisted into the Holocene. These results highlight significant spatial and temporal cultural variability in the African Late Pleistocene, consistent with genomic and palaeoanthropological hypotheses that significant, long-standing inter-group cultural differences shaped the later stages of human evolution in Africa.

Younger Dryas flood tracked Our current concepts of abrupt climate change are strongly influenced by compelling palaeoclimate evidence for events like the Younger Dryas, in which massive changes in climate occurred essentially instantaneously. It is generally thought that an injection of freshwater from the retreating Laurentide Ice Sheet altered the Atlantic Meridional Overturning Circulation and triggered the Younger Dryas, but convincing geological evidence to support this theory has, to date, proven elusive. Now Julian Murton and colleagues at last identify a major flood event that is chronologically consistent with the Younger Dryas. Gravels found above an erosion surface in north-west Canada are consistent with the major flood path running through the Mackenzie River into the Arctic Ocean, rather than south along the Mississippi River or east through the Great Lakes. Our current concepts of abrupt climate change are influenced by palaeoclimate evidence for events such as the Younger Dryas cold interval, in which massive climate changes occurred essentially instantaneously. It is thought that an injection of fresh water from the retreating Laurentide Ice Sheet altered the Atlantic meridional overturning circulation and triggered the Younger Dryas, but convincing geological evidence has been elusive. Here, a major flood event that is chronologically consistent with the Younger Dryas has been identified—through the MacKenzie River into the Arctic Ocean. The melting Laurentide Ice Sheet discharged thousands of cubic kilometres of fresh water each year into surrounding oceans, at times suppressing the Atlantic meridional overturning circulation and triggering abrupt climate change 1 , 2 , 3 , 4 . Understanding the physical mechanisms leading to events such as the Younger Dryas cold interval requires identification of the paths and timing of the freshwater discharges. Although Broecker et al. hypothesized in 1989 that an outburst from glacial Lake Agassiz triggered the Younger Dryas 1 , specific evidence has so far proved elusive, leading Broecker to conclude in 2006 that “our inability to identify the path taken by the flood is disconcerting” 2 . Here we identify the missing flood path—evident from gravels and a regional erosion surface—running through the Mackenzie River system in the Canadian Arctic Coastal Plain. Our modelling of the isostatically adjusted surface in the upstream Fort McMurray region, and a slight revision of the ice margin at this time, allows Lake Agassiz to spill into the Mackenzie drainage basin. From optically stimulated luminescence dating we have determined the approximate age of this Mackenzie River flood into the Arctic Ocean to be shortly after 13,000 years ago, near the start of the Younger Dryas. We attribute to this flood a boulder terrace near Fort McMurray with calibrated radiocarbon dates of over 11,500 years ago. A large flood into the Arctic Ocean at the start of the Younger Dryas leads us to reject the widespread view that Agassiz overflow at this time was solely eastward into the North Atlantic Ocean.

A portfolio can be viewed as the collection of the businesses, policies and practices of constituent companies. We measure investors’ Ownership of this collection. Ownership metrics aggregate an assortment of company specific Environmental, Social and Governance (ESG) characteristics to the portfolio level, and they can inform investment and engagement decisions. Relative to a benchmark, investor Ownership is active and satisfies a zero-sum property, which underscores the distinction between Ownership and impact. Ownership of ESG characteristics may be interpreted as ascribing ethical responsibility, but that conclusion and any decisions that result from it belong to the investor.

Middle Stone Age (MSA) technologies first appear in the archaeological records of northern, eastern and southern Africa during the Middle Pleistocene epoch. The absence of MSA sites from West Africa limits evaluation of shared behaviours across the continent during the late Middle Pleistocene and the diversity of subsequent regionalized trajectories. Here we present evidence for the late Middle Pleistocene MSA occupation of the West African littoral at Bargny, Senegal, dating to 150 thousand years ago. Palaeoecological evidence suggests that Bargny was a hydrological refugium during the MSA occupation, supporting estuarine conditions during Middle Pleistocene arid phases. The stone tool technology at Bargny presents characteristics widely shared across Africa in the late Middle Pleistocene but which remain uniquely stable in West Africa to the onset of the Holocene. We explore how the persistent habitability of West African environments, including mangroves, contributes to distinctly West African trajectories of behavioural stability. The late Middle Pleistocene site of Bargny, Senegal, documents stone tool trends seen across contemporary sites in Africa but which, in West Africa, remain uniquely stable into the Holocene. Palaeoenvironmental data suggest that persistently stable environments in West Africa through the Late Pleistocene, including estuarine refugia, may have supported consistent behavioural responses.

An event stratigraphy of dune stability/instability phases has been reconstructed, using 22 radiocarbon and 13 luminescence dates, for six dunefields along the north coast of Northern Ireland. There is no evidence for dune development prior to ċ. 7000 cal. years BP, during the early-Holocene rapid rise in RSL, and only limited evidence for sand accumulation in association with the RSL maximum. Dunefield dates correspond to either the subsequent regressive phase or, later, the gradual transgressive phase of RSL history in the mid-and late Holocene. At these times accommodation space for dune development and sediment supply were maximized. Episodes of climatic deterioration, particularly at 3100–2400 cal. years BP and 650–50 cal. years BP (the‘Little Ice Age’) were marked by widespread dune instability. A similar coincidence in timing has been recorded for dune systems elsewhere in northwestern Europe and is generally attributed to an increased frequency of storms and storm surges associated with the climatic downturns. However, between-site inconsistencies in the event stratigraphy suggest that site-specific factors (e.g., sediment availability) had a modulating influence on dune regional controls.

The article reports an experimental study of the metal uptake properties of poly(1-methylpyrrol-2-ylsquaraine) particles, in the context of 51 elemental metal complexes. Vagaries of the experimental results meant that the final analysis took place for 43 of these metals. After an initial descriptive analysis, an Analysis of Variance model was fitted. This revealed that several factors, some intrinsic to the metals themselves, others relating to the experimental conditions, have an important influence on the adsorption characteristics of the poly(1-methylpyrrol-2-ylsquaraine) particles. Of these, the most important is the ratio of the number of moles of the metal to the number of moles of the adsorbent particles. X-ray mapping of the poly(1-methylpyrrol-2-ylsquaraine) particles treated with contrast agent revealed that, although adsorption was all throughout the particles, the majority of the agent was adsorbed within 10–15% (diameter distance) of the surface of the particles.

Inland dunefields found in Breckland, East Anglia, UK, have previously been correlated with the widespread late-Devensian coversands of the region and a seventeenth-century‘sandflood’ which is known to have inundated the village of Santon Downham. A programme of optically stimulated luminescence and radiocarbon dating undertaken on the dunes at Wangford Warren and Santon Downham reveals that episodic aeolian activity has taken place during the last 7000 years. Five sand depositional phases on Breckland dunes are identified: c. 6500, c. 1600-1100, c. 500, c. 400-335 and c. 200-30 years before present. Between c. 2120 and 1840 years ago and within the period 1100-300 years ago quiescent periods allowed the development of fen peat and soils. Local controlling factors on aeolian activity in Breckland appear to be related to anthropogenic activities and livestock (sheep and rabbits) reducing vegetation cover, and decreased precipitation and sea levels which led to lowering of water tables. Breckland aeolian activity, when compared to the national and subcontinental Holocene aeolian activity record, shows a high level of concordance. The underlying forcing factor for late-Holocene dune activity in the UK and elsewhere in Europe appears to be climatic instability in the North Atlantic, associated with both the‘Little Ice Age’ and previous similar events which led to increased storminess, climatic variability and lower temperatures.

Fetal structural anomalies, which are detected by ultrasonography, have a range of genetic causes, including chromosomal aneuploidy, copy number variations (CNVs; which are detectable by chromosomal microarrays), and pathogenic sequence variants in developmental genes. Testing for aneuploidy and CNVs is routine during the investigation of fetal structural anomalies, but there is little information on the clinical usefulness of genome-wide next-generation sequencing in the prenatal setting. We therefore aimed to evaluate the proportion of fetuses with structural abnormalities that had identifiable variants in genes associated with developmental disorders when assessed with whole-exome sequencing (WES). In this prospective cohort study, two groups in Birmingham and London recruited patients from 34 fetal medicine units in England and Scotland. We used whole-exome sequencing (WES) to evaluate the presence of genetic variants in developmental disorder genes (diagnostic genetic variants) in a cohort of fetuses with structural anomalies and samples from their parents, after exclusion of aneuploidy and large CNVs. Women were eligible for inclusion if they were undergoing invasive testing for identified nuchal translucency or structural anomalies in their fetus, as detected by ultrasound after 11 weeks of gestation. The partners of these women also had to consent to participate. Sequencing results were interpreted with a targeted virtual gene panel for developmental disorders that comprised 1628 genes. Genetic results related to fetal structural anomaly phenotypes were then validated and reported postnatally. The primary endpoint, which was assessed in all fetuses, was the detection of diagnostic genetic variants considered to have caused the fetal developmental anomaly. The cohort was recruited between Oct 22, 2014, and June 29, 2017, and clinical data were collected until March 31, 2018. After exclusion of fetuses with aneuploidy and CNVs, 610 fetuses with structural anomalies and 1202 matched parental samples (analysed as 596 fetus-parental trios, including two sets of twins, and 14 fetus-parent dyads) were analysed by WES. After bioinformatic filtering and prioritisation according to allele frequency and effect on protein and inheritance pattern, 321 genetic variants (representing 255 potential diagnoses) were selected as potentially pathogenic genetic variants (diagnostic genetic variants), and these variants were reviewed by a multidisciplinary clinical review panel. A diagnostic genetic variant was identified in 52 (8·5%; 95% CI 6·4–11·0) of 610 fetuses assessed and an additional 24 (3·9%) fetuses had a variant of uncertain significance that had potential clinical usefulness. Detection of diagnostic genetic variants enabled us to distinguish between syndromic and non-syndromic fetal anomalies (eg, congenital heart disease only vs a syndrome with congenital heart disease and learning disability). Diagnostic genetic variants were present in 22 (15·4%) of 143 fetuses with multisystem anomalies (ie, more than one fetal structural anomaly), nine (11·1%) of 81 fetuses with cardiac anomalies, and ten (15·4%) of 65 fetuses with skeletal anomalies; these phenotypes were most commonly associated with diagnostic variants. However, diagnostic genetic variants were least common in fetuses with isolated increased nuchal translucency (≥4·0 mm) in the first trimester (in three [3·2%] of 93 fetuses). WES facilitates genetic diagnosis of fetal structural anomalies, which enables more accurate predictions of fetal prognosis and risk of recurrence in future pregnancies. However, the overall detection of diagnostic genetic variants in a prospectively ascertained cohort with a broad range of fetal structural anomalies is lower than that suggested by previous smaller-scale studies of fewer phenotypes. WES improved the identification of genetic disorders in fetuses with structural abnormalities; however, before clinical implementation, careful consideration should be given to case selection to maximise clinical usefulness. UK Department of Health and Social Care and The Wellcome Trust.

The greatest concentration of pans in southern Africa occurs in the western Free State province, South Africa. A feature of many Free State pans is their fringing lunettes, located on the southern and south-eastern margins. Lunette dunes associated with pans in the neighbouring and presently drier Kalahari region show depositional ages, determined by optically stimulated luminescence (OSL) dating, primarily in the Holocene. However, to date, the precise timing of Free State lunette accumulation has not been investigated. The morphology, sedimentology and age of lunettes at five pan sites in the western Free State panfield are reported here. The lunettes form distinct topographic features, with heights up to 5 m above the pan floor, and all have been dissected by gully erosion. Sediment in the sand size class dominates in the lunettes, often overlying clay-rich basal or pan floor sediments. The intra- and intersite data consistency of 46 OSL ages is interpreted as reflecting regional causal factors responsible for lunette accretion, with phases of lunette building at 12—10 ka, 5.5—3 ka, 2—1 ka and 0.3—0.07 ka ago. These are in good agreement with the findings from pan-fringing lunettes in the southwest Kalahari and consistent with established records of palaeocirculation and wind direction over central southern Africa during the late Pleistocene. Lunettes in the western Free State are currently not in a major accretion phase. They are subject to degradation by localized fluvial erosion, with sediment being recycled into the pans.