11 research outputs found

    Reef island evolution in a turbid-water coral reef province of the Indo-Pacific

    Get PDF
    Coral reef islands are vulnerable landforms to environmental change. Constructed of largely unconsolidated reef-derived sediments, they are highly sensitive to variations in metocean boundary conditions, raising global concern about their future resilience and stability in the face of increased natural hazards, sea-level rise and anthropogenic climate change. This study examines the evolution of an inshore turbid reef island from the southern Pilbara region of Western Australia (Indo-Pacific) using detailed analyses of island chronostratigraphy (composition, texture) and geochronology (21 in-situ radiometric dates) from Eva Island. Downcore, composition of island-grade (reef-derived) sediments were homogenous, dominated by molluscan (37%–42%) and coral (32%–37%) constituents. The 14C radiometric dating of island sediments, beachrock and coral microatolls identified five stages of island formation across changing sea-level regimes over the mid to late Holocene: (1) limestone platform accretion at ca 6,000 cal yr BP, coinciding with reef decline or ‘give-up’ on neighbouring Exmouth Gulf reefs; (2) sand cay (i.e. core) initiation and vertical aggregation at ca 5,000 cal yr BP during the point of sea-level regression to current levels; (3) major accretion and lateral progradation of the island between 3,500 cal yr BP and 2,500 cal yr BP including the modification of island shorelines through alongshore reworking of sediment; (4) lateral accretion and minor expansion to the north and formation of beachrock pavement between 2,500 and 650 cal yr BP; and (5) planform adjustment (erosion of the north-west island) and backstepping under stabilised sea levels over the past 650 years. While this model is comparative to studies on island formation following incremental sea-level fall following the mid-Holocene highstand, it demonstrates active landform readjustment under stabilised sea levels over the past 2,000 years, probably the influence of local-scale metocean boundary conditions within climate windows across the mid to late Holocene period (i.e. independent of sea-level fluctuations). Importantly, while sediment production rates are predicted to be lower in turbid-water reef systems than clear water, Eva Island shows no change in carbonate producers (i.e. proportion of mollusc and coral) over the course of island building, indicating the carbonate factory has not experienced significant adjustments in reef ecology, but has remained stable despite low water quality

    Predator management for breeding waders: a review of current evidence and priority knowledge gaps

    Get PDF
    Rapid declines in breeding wader populations across the world have prompted the development of a series of conservation tools, many of which are designed to influence productivity. Across western Europe, efforts to reverse population declines are typically limited by high levels of nest and chick predation, and managing this predator impact has been a major research focus in the last two decades. A workshop held at the 2019 International Wader Study Group conference aimed to synthesise current understanding of predator management tools and to use expert knowledge to identify and prioritise important knowledge gaps in this area. Here we review the four predator management tools that were described (predator diversion, exclusion, lethal control and headstarting), together with insights into the potential responses of mammalian predators to these management tools. The expert assessment of important areas for future work highlighted the need to: (1) increase our knowledge of predators and their responses to management interventions; (2) ensure our science connects to policy, practitioners and members of the public; and (3) establish clear and consistent goals for the future of breeding wader populations to inform the development and deployment of these management tools

    Interventions to Promote Healthy Eating, Physical Activity and Smoking in Low-Income Groups: a Systematic Review with Meta-Analysis of Behavior Change Techniques and Delivery/Context

    Get PDF
    Purpose Healthy eating, physical activity and smoking interventions for low-income groups may have small, positive effects. Identifying effective intervention components could guide intervention development. This study investigated which content and delivery components of interventions were associated with increased healthy behavior in randomised controlled trials (RCTs) for low-income adults. Method Data from a review showing intervention effects in 35 RCTs containing 45 interventions with 17,000 participants were analysed to assess associations with behavior change techniques (BCTs) and delivery/context components from the template for intervention description and replication (TIDieR) checklist. The associations of 46 BCTs and 14 delivery/context components with behavior change (measures of healthy eating, physical activity and smoking cessation) were examined using random effects subgroup meta-analyses. Synergistic effects of components were examined using classification and regression trees (meta-CART) analyses based on both fixed and random effects assumptions. Results For healthy eating, self-monitoring, delivery through personal contact, and targeting multiple behaviors were associated with increased effectiveness. Providing feedback, information about emotional consequences, or using prompts and cues were associated with reduced effectiveness. In synergistic analyses, interventions were most effective without feedback, or with selfmonitoring excluding feedback. More effective physical activity interventions included behavioral practice/rehearsal or instruction, focussed solely on physical activity or took place in home/community settings. Information about antecedents was associated with reduced effectiveness. In synergistic analyses, interventions were most effective in home/community settings with instruction. No associations were identified for smoking. Conclusion This study identified BCTs and delivery/context components, individually and synergistically, linked to increased and reduced effectiveness of healthy eating and physical activity interventions. The identified components should be subject to further experimental study to help inform the development effective behavior change interventions for low-income groups to reduce health inequalities

    HARMONI at ELT: project status and instrument overview

    Get PDF

    Depositional history and archaeology of the central Lake Mungo lunette, Willandra Lakes, southeast Australia

    No full text
    Lake Mungo, presently a dry lake in the semi-arid zone of southeastern Australia, preserves a unique record of human settlement and past environmental change within the transverse lunette that built up on its downwind margin. The lunette is \u3e30 km long and the variable morphology along its length suggests spatial variability in deposition over time. Consequently this presents differential potential for the preservation of past activity traces of different ages along the lunette. Earlier work at Lake Mungo focused primarily on the southern section of the lunette, where two ritual burials of considerable antiquity were found. Here we describe the depositional history of the central section of the Lake Mungo lunette, together with the first single grain optically stimulated luminescence (OSL) chronology of the full stratigraphic sequence and of three hearths. We thereby lay the foundation for systematic investigation of the distribution of archaeological traces through the sedimentary record. The older depositional units (Lower and Upper Mungo) were deposited ca. 50–40 ka and ∌34 ka respectively, and are substantially thinner in the central section of the lunette compared with the south. By contrast, the overlying unit of interbedded sands and clayey sands (Arumpo–Zanci units), deposited ca. 25–14 ka, is markedly thicker and dominates the stratigraphic sequence in the central portion of the lunette. Although the sequence broadly reflects previous models of the lunette\u27s depositional history and changing hydrological conditions, our results indicate spatially variable deposition of sediments, possibly as a result of changes in prevailing wind regimes. Archaeological traces are exposed in all stratigraphic units deposited after ca. 50 ka, including sediments deposited after the final lake drying ca. 15 ka, indicating human occupation of the area under a range of palaeoenvironmental conditions. Dating and stratigraphical examination of individual hearth features demonstrates that even within individual stratigraphic units, human occupation persisted under variable conditions. Mid-Holocene occupation of the area following the final lake retreat took place during a period of relatively humid climate

    Fragment-Based Discovery of Allosteric Inhibitors of SH2 Domain-Containing Protein Tyrosine Phosphatase‑2 (SHP2)

    No full text
    The ubiquitously expressed protein tyrosine phosphatase SHP2 is required for signaling downstream of receptor tyrosine kinases (RTKs) and plays a role in regulating many cellular processes. Genetic knockdown and pharmacological inhibition of SHP2 suppresses RAS/MAPK signaling and inhibit the proliferation of RTK-driven cancer cell lines. Here, we describe the first reported fragment-to-lead campaign against SHP2, where X-ray crystallography and biophysical techniques were used to identify fragments binding to multiple sites on SHP2. Structure-guided optimization, including several computational methods, led to the discovery of two structurally distinct series of SHP2 inhibitors binding to the previously reported allosteric tunnel binding site (Tunnel Site). One of these series was advanced to a low-nanomolar lead that inhibited tumor growth when dosed orally to mice bearing HCC827 xenografts. Furthermore, a third series of SHP2 inhibitors was discovered binding to a previously unreported site, lying at the interface of the C-terminal SH2 and catalytic domains

    Fragment-Based Discovery of Allosteric Inhibitors of SH2 Domain-Containing Protein Tyrosine Phosphatase‑2 (SHP2)

    No full text
    The ubiquitously expressed protein tyrosine phosphatase SHP2 is required for signaling downstream of receptor tyrosine kinases (RTKs) and plays a role in regulating many cellular processes. Genetic knockdown and pharmacological inhibition of SHP2 suppresses RAS/MAPK signaling and inhibit the proliferation of RTK-driven cancer cell lines. Here, we describe the first reported fragment-to-lead campaign against SHP2, where X-ray crystallography and biophysical techniques were used to identify fragments binding to multiple sites on SHP2. Structure-guided optimization, including several computational methods, led to the discovery of two structurally distinct series of SHP2 inhibitors binding to the previously reported allosteric tunnel binding site (Tunnel Site). One of these series was advanced to a low-nanomolar lead that inhibited tumor growth when dosed orally to mice bearing HCC827 xenografts. Furthermore, a third series of SHP2 inhibitors was discovered binding to a previously unreported site, lying at the interface of the C-terminal SH2 and catalytic domains
    corecore