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Autophagy is the process by which damaged regions of the cytoplasm and intracellular pathogens are degraded. This mechanism often serves an adaptive role in cells, enhancing their survival. It plays a direct or indirect role in the development of various pathological conditions within the body. This phenomenon is common in various malignant diseases, where autophagy is associated with the resistance of transformed cells to chemotherapy. Conversely, abnormal activation of autophagy can trigger cell death, a process often seen in neurodegenerative conditions. Given that dysregulation of autophagy is associated with the progression of numerous pathological conditions, this is of significant interest to the developers of drugs that can effectively modulate autophagy for both basic research and clinical applications. Here, we provide a brief description of the mechanism of macroautophagy, the most prevalent form of autophagy identified in humans. We also discuss the clinical potential of drugs that can modulate autophagy, highlighting their use in combating diseases associated with direct or indirect dysregulation of this essential process. [ABSTRACT FROM AUTHOR]

Empirical data regarding payments to participants in research is limited. This lack of information constrains our understanding of the effectiveness of payments to achieve scientific goals with respect to recruitment, retention, and inclusion. We conducted a content analysis of consent forms and protocols available on clinicaltrials.gov to determine what information researchers provide regarding payment. We extracted data from HIV (n = 101) and NIMH-funded studies (n = 65) listed on clinicaltrials.gov that had publicly posted a consent form. Using a manifest content analysis approach, we then coded the language regarding payment from the consent document and, where available, protocol for purpose and method of the payment. Although not part of our original planned analysis, the tax-related information that emerged from our content analysis of the consent form language provided additional insights into researcher payment practices. Accordingly, we also recorded whether the payment section mentioned social security numbers (or other tax identification number) in connection with payments and whether it made any statements regarding the Internal Revenue Service or the tax status of payments. We found studies commonly offered payment, but did not distinguish between the purposes for which payment may be offered (i.e., compensation, reimbursement, incentive, or appreciation). We also found studies that excluded some participants from receiving payment or treated them differently from other participants in the study. Differential treatment was typically linked to US tax laws and other legal requirements. A number of US studies also discussed the need to collect Social Security numbers and income reporting based on US tax laws. Collectively, these practices disadvantage some participants and may interfere with efforts to conduct more inclusive research. [ABSTRACT FROM AUTHOR]

The discovery of new compounds with pharmacological properties is usually a lengthy, laborious and expensive process. Thus, there is increasing interest in developing workflows that allow for the rapid synthesis and evaluation of libraries of compounds with the aim of identifying leads for further drug development. Herein, we apply combinatorial synthesis to build a library of 90 iridium(III) complexes (81 of which are new) over two synthesise‐and‐test cycles, with the aim of identifying potential agents for photodynamic therapy. We demonstrate the power of this approach by identifying highly active complexes that are well‐tolerated in the dark but display very low nM phototoxicity against cancer cells. To build a detailed structure–activity relationship for this class of compounds we have used density functional theory (DFT) calculations to determine some key electronic parameters and study correlations with the experimental data. Finally, we present an optimised semi‐automated synthesise‐and‐test protocol to obtain multiplex data within 72 hours. [ABSTRACT FROM AUTHOR]

The discovery of new compounds with pharmacological properties is usually a lengthy, laborious and expensive process. Thus, there is increasing interest in developing workflows that allow for the rapid synthesis and evaluation of libraries of compounds with the aim of identifying leads for further drug development. Herein, we apply combinatorial synthesis to build a library of 90 iridium(III) complexes (81 of which are new) over two synthesise‐and‐test cycles, with the aim of identifying potential agents for photodynamic therapy. We demonstrate the power of this approach by identifying highly active complexes that are well‐tolerated in the dark but display very low nM phototoxicity against cancer cells. To build a detailed structure–activity relationship for this class of compounds we have used density functional theory (DFT) calculations to determine some key electronic parameters and study correlations with the experimental data. Finally, we present an optimised semi‐automated synthesise‐and‐test protocol to obtain multiplex data within 72 hours. [ABSTRACT FROM AUTHOR]

Atolls islands are biogenic landforms that are intrinsically capable of adjusting their size, position, and elevation to changing sea levels. The vulnerability of atoll islands to sea level rise is not intrinsically due to their low elevation but primarily due to the loss of their island building capacity. The geophysical processes that control atoll island accretion are being impacted on global and local scales. Protecting and restoring the natural geophysical processes of atoll island accretion through local conservation actions is key to unlocking nature-based opportunities for enhancing atoll resilience to global change. Atoll islands are often perceived as inevitably lost due to rising sea levels. However, unlike other islands, atoll islands are dynamic landforms that have evolved, at least historically, to vertically accrete at a pace commensurate with changing sea levels. Rather than atoll islands' low elevation per se , the impairment of natural accretion processes is jeopardising their persistence. While global marine impacts are deteriorating coral reefs, local impacts also significantly affect accretion, together potentially tipping the scales toward atoll island erosion. Maintaining atoll island accretion requires intact sediment generation on coral reefs, unobstructed sediment transport from reef to island, and available vegetated deposition sites on the island. Ensuring the persistence of atoll islands must include global greenhouse gas emission reduction and local restoration of accretion processes. [ABSTRACT FROM AUTHOR]

Matheen, N. and Kench, P.S., 2024. Morphological response of coral reef islands to the 2019 extreme positive Indian Ocean Dipole event. Journal of Coastal Research, 40(2), 246–256. Charlotte (North Carolina), ISSN 0749-0208. The influence of the Indian Ocean Dipole (IOD) on winds, waves, and water levels has been studied in considerable detail, but the effect of these anomalous IOD-induced metocean conditions on coastal zones has so far received limited attention. This study analyses the impact of IOD events on the morphological response of coral reef islands by undertaking a case study of five islands in the Maldivian archipelago during the 2019 extreme positive IOD (pIOD) event. A 6-year dataset of shorelines before, during, and after the pIOD event was analysed to establish the magnitude of year-on-year variability and seasonal oscillation trends in the shorelines and thereby identify variability induced by the pIOD event. The results indicate a departure in the shorelines beyond the magnitude of the year-on-year variability during the mature phase of the pIOD event (September–November 2019) and a substantial change in the morphodynamics of the shoreline in the months immediately following the end of the pIOD event (November 2019–April 2020). It was identified that the anomalous metocean conditions during the pIOD event caused a change in the seasonally oscillating shoreline buffer around the island, with potential implications on medium-term island change and overall stability for the vegetated island core. The results showed that it took up to 2 years after the end of the pIOD event for the shorelines to return to their pre-pIOD state. [ABSTRACT FROM AUTHOR]

• A deep learning-based framework is proposed to investigate defect-induced fatigue scatter. • X-ray tomography of surface morphology is regenerated using SliceGAN architecture for the first time. • Reveal the influence of microscale surface defect on stress concentration and fatigue scatter. • Identify fatigue lifetime indicator with correlation analysis. • Develop probabilistic stress-life curve to reduce uncertainty in fatigue design. The layer-based deposition mechanism during electron beam powder bed fusion (PBF-EB) inevitably induces significant surface irregularities, which often act as stress concentrators under cyclic fatigue load, resulting in early fatigue failure and scattered lifetime. Reliable design of additively manufactured metallic lattice structures necessitates a comprehensive understanding of the fatigue behaviour of micro-sized structural parts, typically obtained through expensive and time-consuming full-scale fatigue testing. This study proposed a deep learning-based framework to predict defect-induced fatigue scatter in micro-sized as-built titanium parts produced with PBF-EB technique. The surface morphology synthesized by generative adversarial networks (GANs) was incorporated with finite element modelling to investigate defect-induced stress concentrations. A fatigue damage model, based on continuum damage mechanics and theory of critical distances, was developed to predict fatigue lifetime. The synthesized morphology showed good agreement with experimental results in roughness evaluation. Using the proposed framework, the fatigue scatter was successfully reproduced, and a probabilistic lifetime design curve was developed accordingly to facilitate reliable and cost-effective fatigue design. The primary contributions of this study are the first-time application of a GAN architecture for synthesizing realistic morphology of micro-sized as-built PBF-EB Ti6Al4V parts with significant surface irregularities, and the investigation of defect-induced fatigue scatter using synthetic morphology and numerical methods. The results provide new insights into the effects of surface irregularity on stress concentration and scattering of lifetime in micro-sized as-built titanium parts. [Display omitted] [ABSTRACT FROM AUTHOR]

Modelling the impact of a material's mesostructure on device level performance typically requires access to 3D image data containing all the relevant information to define the geometry of the simulation domain. This image data must include sufficient contrast between phases, be of high enough resolution to capture the key details, but also have a large enough 3D field‐of‐view to be representative of the material in general. It is rarely possible to obtain data with all of these properties from a single imaging technique. In this paper, we present a method for combining information from pairs of distinct but complementary imaging techniques in order to accurately reconstruct the desired multi‐phase, high‐resolution, representative, 3D images. Specifically, the deep convolutional generative adversarial networks to implement super‐resolution, style‐transfer and dimensionality expansion. It is believed that this data‐driven approach is superior to previously reported statistical material reconstruction methods, both in terms of its fidelity and ease of use. Furthermore, much of the data required to train this algorithm already exists in the literature, waiting to be combined. As such, our open‐source code could precipitate a step change in the materials sciences by generating the desired high quality image volumes necessary to simulate behaviour at the mesoscale. [ABSTRACT FROM AUTHOR]

The fifth edition of the WHO Classification of Tumours of the Urinary and Male Genital Systems encompasses several updates to the classification and diagnosis of prostatic carcinoma as well as incorporating advancements in the assessment of its prognosis, including recent grading modifications. Some of the salient aspects include: (1) recognition that prostatic intraepithelial neoplasia (PIN)‐like carcinoma is not synonymous with a pattern of ductal carcinoma, but better classified as a subtype of acinar adenocarcinoma; (2) a specific section on treatment‐related neuroendocrine prostatic carcinoma in view of the tight correlation between androgen deprivation therapy and the development of prostatic carcinoma with neuroendocrine morphology, and the emerging data on lineage plasticity; (3) a terminology change of basal cell carcinoma to "adenoid cystic (basal cell) cell carcinoma" given the presence of an underlying MYB::NFIB gene fusion in many cases; (4) discussion of the current issues in the grading of acinar adenocarcinoma and the prognostic significance of cribriform growth patterns; and (5) more detailed coverage of intraductal carcinoma of prostate (IDC‐P) reflecting our increased knowledge of this entity, while recommending the descriptive term atypical intraductal proliferation (AIP) for lesions falling short of IDC‐P but containing more atypia than typically seen in high‐grade prostatic intraepithelial neoplasia (HGPIN). Lesions previously regarded as cribriform patterns of HGPIN are now included in the AIP category. This review discusses these developments, summarising the existing literature, as well as the emerging morphological and molecular data that underpins the classification and prognostication of prostatic carcinoma. [ABSTRACT FROM AUTHOR]

The efficacy of many drugs can be limited by undesirable properties, such as poor aqueous solubility, low bioavailability, and "off‐target" interactions. To combat this, various drug carriers have been investigated to enhance the pharmacological profile of therapeutic agents. In this work, we demonstrate the use of mechanical protection to "cage" a DNA‐targeting metallodrug within a photodegradable rotaxane. More specifically, we report the synthesis of rotaxanes incorporating as a stoppering unit a known G‐quadruplex DNA binder, namely a PtII‐salphen complex. This compound cannot interact with DNA when it is part of the mechanically interlocked assembly. The second rotaxane stopper can be cleaved by either light or an esterase, releasing the PtII‐salphen complex. This system shows enhanced cell permeability and limited cytotoxicity within osteosarcoma cells compared to the free drug. Light activation leads to a dramatic increase in cytotoxicity, arising from the translocation of PtII‐salphen to the nucleus and its binding to DNA. [ABSTRACT FROM AUTHOR]

The efficacy of many drugs can be limited by undesirable properties, such as poor aqueous solubility, low bioavailability, and "off‐target" interactions. To combat this, various drug carriers have been investigated to enhance the pharmacological profile of therapeutic agents. In this work, we demonstrate the use of mechanical protection to "cage" a DNA‐targeting metallodrug within a photodegradable rotaxane. More specifically, we report the synthesis of rotaxanes incorporating as a stoppering unit a known G‐quadruplex DNA binder, namely a PtII‐salphen complex. This compound cannot interact with DNA when it is part of the mechanically interlocked assembly. The second rotaxane stopper can be cleaved by either light or an esterase, releasing the PtII‐salphen complex. This system shows enhanced cell permeability and limited cytotoxicity within osteosarcoma cells compared to the free drug. Light activation leads to a dramatic increase in cytotoxicity, arising from the translocation of PtII‐salphen to the nucleus and its binding to DNA. [ABSTRACT FROM AUTHOR]

The efficacy of many drugs can be limited by undesirable properties, such as poor aqueous solubility, low bioavailability, and “off‐target” interactions. To combat this, various drug carriers have been investigated to enhance the pharmacological profile of therapeutic agents. In this work, we demonstrate the use of mechanical protection to “cage” a DNA‐targeting metallodrug within a photodegradable rotaxane. More specifically, we report the synthesis of rotaxanes incorporating as a stoppering unit a known G‐quadruplex DNA binder, namely a PtII‐salphen complex. This compound cannot interact with DNA when it is part of the mechanically interlocked assembly. The second rotaxane stopper can be cleaved by either light or an esterase, releasing the PtII‐salphen complex. This system shows enhanced cell permeability and limited cytotoxicity within osteosarcoma cells compared to the free drug. Light activation leads to a dramatic increase in cytotoxicity, arising from the translocation of PtII‐salphen to the nucleus and its binding to DNA. [ABSTRACT FROM AUTHOR]

The ongoing development of Jeh Island in the Marshall Islands was investigated using aerial photographs, high‐resolution satellite imagery, and radiometric dating of island sediments. Remote sensing observations show the present‐day island of Jeh is the product of two or more smaller islands merging together between 1943 and 2006 which are continuing to expand despite local sea‐level rise (SLR). Remote sensing observations show modern island development involving a complex multistage merging of smaller islands on a linear atoll rim. Radiometric ages of sediments demonstrate that island development is occurring through the active generation and delivery of modern sediments. Results highlight that at sites where sediment production regimes are in a healthy state, island building under conditions of SLR is possible. The findings have implications for interpreting island evolution from morphostratigraphic studies and understanding future island behavior with further SLR. Plain Language Summary: Atoll islands are low‐lying deposits of reef‐derived sediments deposited in the last ~5,000 yr. Surprisingly, many atoll islands have grown in planform size since the mid‐20th century, despite local sea‐level rise. This recent island growth suggests that islands are sourcing sediment, whether relict material or new, freshly produced reef material. Remote imagery from 1943 and 2006 shows the island of Jeh in the Marshall Islands has grown through the merger of at least two islands and the continued expansion of the island. By radiocarbon dating material from parts of the island observed to have been deposited since 1943, we are able to show that modern, reef sediments are actively driving island growth. These findings show that islands are able to grow under present‐day conditions by accumulating sediment produced on the surrounding reef. Key Points: Island merging and expansion were observed over the last 70 yr using remote imageryRadiocarbon dating of recent deposits indicates island growth is driven by the generation of modern sedimentIsland formation and change were observed over both rising and falling sea level [ABSTRACT FROM AUTHOR]

This study identifies factors associated with freshmen retention rates at a mid‐size private university. A key finding from our analysis is that roommates' academic efforts, residing on an honours floor and membership in co‐curricular groups increase retention. We also confirm many standard results in the literature regarding the impact on retention rates, such as student motivation and ability, and financial aid. We show that a timely housing application, closer proximity to home, a higher number of schools on a student's Free Application for Federal Student Aid and peer effects impact freshman retention. Our results suggest that a more sophisticated dormroom assignment algorithm matching students' abilities and interests could be considered to increase freshman retention rates among private institutions. [ABSTRACT FROM AUTHOR]

Sea-level rise and increased storminess are expected to destabilize low-lying reef islands formed on coral reef platforms, and increased flooding is expected to render them uninhabitable within the coming decades. Such projections are founded on the assumption that islands are geologically static landforms that will simply drown as sea-level rises. Here, we present evidence from physical model experiments of a reef island that demonstrates islands have the capability to morphodynamically respond to rising sea level through island accretion. Challenging outputs from existing models based on the assumption that islands are geomorphologically inert, results demonstrate that islands not only move laterally on reef platforms, but overwash processes provide a mechanism to build and maintain the freeboard of islands above sea level. Implications of island building are profound, as it will offset existing scenarios of dramatic increases in island flooding. Future predictive models must include the morphodynamic behavior of islands to better resolve flood impacts and future island vulnerability. [ABSTRACT FROM AUTHOR]

A new storm model of reef island formation is presented for Tutaga island, Funafuti atoll, Tuvalu, based on detailed observations and radiometric dating of large coral blocks (>2 m diameter) deposited in a dense array across the reef flat and which compose the island fabric. Dating of coral blocks indicates that island formation was nonlinear and characterized by a mixed age structure resulting from episodic deposition of spatially dispersed fields of coral heads and boulders associated with four discrete storm phases over the past 1100 yr. Island accumulation occurred 750-300 yr ago at current sea level across a sea level-constrained reef flat. Results highlight a critical relationship between coral growth and temporal lag between the storms necessary to generate blocks for island building. Results also indicate that island deposits are promising archives for unraveling paleo-storm frequencies at mid-ocean locations. [ABSTRACT FROM AUTHOR]

ABSTRACT Beetham, E.; Kench, P.S., and Popinet, S., 2018. Model skill and sensitivity for simulating wave processes on coral reefs using a shock-capturing Green-Naghdi solver. Wave-flume data from published benchmark experiments were used to extensively evaluate numerical model skill and sensitivity for applying a shock-capturing Green-Naghdi (GN) model to simulate nonlinear wave-transformation processes on complex coral reefs. Boussinesq-type models that utilise nonlinear shallow-water equations (NSWEs) to represent wave breaking and dissipation hold significant potential for understanding coastal hazards associated with global environmental change and sea-level rise. These fully nonlinear phase-resolving models typically require a threshold condition to switch from dispersive equations to shock-capturing NSWEs in areas of active wave breaking. However, limited information exists regarding how this splitting approach influences the behaviour of different surf-zone processes that contribute to wave runup and inundation on reef environments. This paper presents a comprehensive analysis of model sensitivity to explore how input parameters that control wave breaking and dissipation influence the behaviour of sea-swell waves, infragravity waves, wave setup, runup, and solitary waves on coral reefs. Results show that each wave process exhibits unique sensitivity to the free-surface slope threshold (B) that is used to represent areas of active wave breaking by locally switching from the weakly dispersive GN equations to the shock-capturing NSWEs. Accurate representation of all wave processes, however, can be achieved if the wave-face steepens to at least 35° (B ≥ 0.7) before breaking is initiated. Results from this research support and encourage the use of nonlinear phase-resolving wave models as tools for academic research, coastal management, coastal engineering, and hazard forecasting on atoll and fringing reef environments. [ABSTRACT FROM AUTHOR]

ABSTRACT Kench, P.S.; Ryan, E.J.; Owen, S.; Bell, R.; Lawrence, J.; Glavovic, B.; Blackett, P.; Becker, J.; Schneider, P.; Allis, M.; Dickson, M., and Rennie, H.G. 2018. Co-creating resilience solutions to coastal hazards through an interdisciplinary research project in New Zealand, In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1496–1500. Coconut Creek (Florida), ISSN 0749-0208. Coastal communities ‘living at the edge’ face intensification and acceleration of coastal hazard risk in the face of climate change. Communities will need to be adaptive in reducing these risks now and over long timeframes. Developing coastal hazard adaptation pathways requires co-production of interdisciplinary knowledge between scientists, policy makers and communities. However, there remains little guidance and limited dialogue about the research practices and frameworks that underpin co-created research. In a first for New Zealand, a co-created research programme is underway titled ‘Living at the Edge’ that aims to improve the resilience of coastal communities to coastal hazards. This paper provides novel insights into the complexities underpinning the formative stages of co-created research, drawing on practical experience from the Living at the Edge project. We explore the enablers and shapers that led to co-created shifts in the research project objectives and framework. Notions of integration, trust, and flexibility are three fundamental aspects that influenced the early stages of co-creation. The importance of bridging interactions with actors early on in co-created projects is exemplified. [ABSTRACT FROM AUTHOR]

Kench, P.S.; Ryan, E.J.; Owen, S.; Bell, R.; Lawrence, J.; Glavovic, B.; Blackett, P.; Becker, J.; Schneider, P.; Allis, M.; Dickson, M., and Rennie, H.G. 2018. Co-creating resilience solutions to coastal hazards through an interdisciplinary research project in New Zealand, In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1496–1500. Coconut Creek (Florida), ISSN 0749-0208. Coastal communities 'living at the edge' face intensification and acceleration of coastal hazard risk in the face of climate change. Communities will need to be adaptive in reducing these risks now and over long timeframes. Developing coastal hazard adaptation pathways requires co-production of interdisciplinary knowledge between scientists, policy makers and communities. However, there remains little guidance and limited dialogue about the research practices and frameworks that underpin co-created research. In a first for New Zealand, a co-created research programme is underway titled 'Living at the Edge' that aims to improve the resilience of coastal communities to coastal hazards. This paper provides novel insights into the complexities underpinning the formative stages of co-created research, drawing on practical experience from the Living at the Edge project. We explore the enablers and shapers that led to co-created shifts in the research project objectives and framework. Notions of integration, trust, and flexibility are three fundamental aspects that influenced the early stages of co-creation. The importance of bridging interactions with actors early on in co-created projects is exemplified. [ABSTRACT FROM AUTHOR]

Coral reef islands are amongst the most vulnerable environments to sea‐level rise (SLR). Recent physical and numerical modeling studies have demonstrated that overwash processes may enable reef islands to keep up with SLR through island accretion. Sediment supply to these islands from the surrounding reef system is critical in understanding their morphodynamic adjustments, but is poorly constrained due to insufficient knowledge about sediment delivery rates. This paper provides the first estimation of sediment delivery rates to coral reef islands. Analysis of topographic and geochronological data from 28 coral reef islands indicates an average rate of sediment delivery of c. 0.1 m3 m−1 yr−1, but with substantial inter‐island variability. Comparison with carbonate sediment production rates from census‐based studies suggests that this represents one quarter of the amount of sediment produced on the reef platform. Results of this study are useful in future modeling studies for predicting morphodynamic adjustments of coral reef islands to SLR. Plain Language Summary: Low‐lying coral reef islands are under threat of sea‐level rise (SLR). However, when these islands are flooded, ocean waves can bring in sediment that can increase the island elevation. This would enable coral reef islands to better withstand flooding in the future. Knowing how much sediment is brought in will help in our understanding of future changes to these islands due to SLR. In this paper, we use data from 28 Indo‐Pacific coral reef islands to compute sediment supply to the islands. We find that on average 0.1 m3 of sediment (roughly 100 kg) is delivered each year for every meter of island shoreline. We further suggest that this implies that only one quarter of the sediments produced by the coral reef system is delivered to the island shoreline. Most of the sediment produced remains on the reef flat or is exported to the ocean or the lagoon. Our results will help future studies to predict more accurately how coral reef islands will adjust to SLR. Key Points: We provide the first estimates of carbonate sediment delivery rates to 28 coral reef islands using all data available from the literatureSediment delivery to the reef islands occurs at a rate of c. 0.1 m3 m−1 yr−1, but with substantial inter‐island variabilityWhere island building has been continuous through island history, long‐term delivery rates provide valuable estimates for contemporary rates [ABSTRACT FROM AUTHOR]

Understanding how and why the world’s coastlines are changing is a pressing international concern in a context of rising sea levels, increased climatic variability and intensifying coastal development. Medium to long-term records of coastal change are rare worldwide and often limited to individual beach compartments. This study presents a 70-year (1940–2010) aerial imagery record to compare decadal changes in shoreline position across four high-energy west coast beaches near Auckland, New Zealand/Aotearoa: Whatipu, Karekare, Piha and Te Henga (Bethells). The common exposure of these adjacent mesotidal beaches to changing wind and wave conditions might, if they present the dominant controls on shoreline position, be expected to produce synchronous change. Whatipu (935 m), Piha (32 m) and Te Henga (52 m) showed net overall progradation for the study period, while Karekare retreated slightly (−4.1 m). All except Whatipu underwent periods of beachwide erosion. Shoreline change was not coherent between beaches, despite similar exposure to variations in wind, wave and sea level. Variable sediment supply from northward littoral drift is implicated as the primary control on decadal-scale shoreline change for these beaches, highlighting the importance of local context in influencing shoreline response to changing environmental conditions. [ABSTRACT FROM PUBLISHER]

Encrusting marine calcifying organisms, including coralline algae, bryozoans, calcareous worms, foraminifera and oysters, contribute to the geological development of reefs by precipitating calcium carbonate that binds detrital sediment and coral framework, and may produce new sediment after their death. However, it is difficult to quantify the relative importance of encrusting communities within contemporary reef carbonate production budgets because of a lack of regional datasets of either encrusting calcification or diversity, and the factors that control their settlement and growth. Here, we report rates of encrusting carbonate production for the Maldives in the Indian Ocean, determined by deploying artificial settlement substrates in shallow-water reef sites for 13 months. Eight taxonomic groups are identified with high average rates of net calcification (mean = 0.056 ± 0.02 g cm − 2 yr − 1 ). Encrusting communities vary between exposed (upwards-facing) and cryptic (downwards-facing) reef habitats ( p < 0.05), driving inter-habitat differences in carbonate production rates (median cryptic = 0.066 g cm − 2 yr − 1 ; median exposed = 0.042 g cm − 2 yr − 1 ). These changes are a function of differences in light availability, grazing pressure, and wave exposure reflecting reversing monsoon conditions. Non-geniculate coralline algae are the dominant encrusting group (~ 50% cover) and major contributors to net calcification. The rapid expansion of coralline algae on post-mortem coral frameworks following the 2016 mass bleaching event in the Maldives has important implications for short-term carbonate cycling and reef budgetary states (pre-bleaching encrusting production = 0.24 kg m − 2 yr − 1 ; post-bleaching = 0.40 kg m − 2 yr − 1 ). Our findings suggest that encrusting communities add meaningful quantities of carbonate to reefs, and that their increased expression following declines in coral health could offset negative budgets on reefs where bioerosion rates are low, and aid future reef recovery by facilitating coral settlement. [ABSTRACT FROM AUTHOR]

Measurements of wave transformation, beachface cobble transport and shoreline morphology change were undertaken over a 14 month period at Fatato Island, a cobble and sand ‘motu’ on the southeast rim of Funafuti Atoll, Tuvalu. Results document significant cobble transport and beach profile change on Fatato during a year in the absence of any significant high energy wave events. Changes in beachface volume were measured on 11 across-shore beach profiles, and show marked variations of + 7.1 and − 7.01 m 3 between profiles and between survey periods. Net volumetric beachface change over the 14 month experiment was approximately zero, indicating a balance between erosion and deposition and net conservation of sediment volume on the ocean shoreline. Cobble movement was measured using Passive Integrated Transponder (PIT) tags inserted in 300 randomly selected clasts (mean b-axis = 75 mm) on the mid-beachface. Tagged particles were re-surveyed after 6 and 14 months, achieving 76% recovery, and identify large excursions of clasts on the beachface and dominant southwest alongshore transport, with an average net movement of 68 m after 14 months. A simple agent based probabilistic model was developed to simulate cobble movement and explore the coupling between hydrodynamic and shoreline processes. Model simulations reveal: predominant south-westerly cobble transport is driven by mean wave conditions associated with easterly trade winds, and; long-period swell events that approach the reef from the south drive episodic north-easterly transport reversals and significant onshore transport that can strand particles on the upper beach. Results present the first observations of morphodynamic behaviour of an atoll motu and highlight the highly dynamic nature of motu shorelines under mean energy conditions. Such results challenge conventional perspectives that motu are storm adjusted landforms that require extreme events to stimulate geomorphic change and inform future projections of island change. [ABSTRACT FROM AUTHOR]

Parrotfish play a key functional role on coral reefs as external bioerosion agents and produce large quantities of carbonate sediment as a by-product of grazing on reef surfaces. Parrotfish are therefore an important potential source of sediment for island construction and maintenance within atoll reef environments, particularly under future scenarios of sea level rise and island morphological change. Here, we present the first field-based estimates of excavating parrotfish erosion ( Chlorurus sordidus and Chlorurus strongylocephalus ) within the Indian Ocean and quantify the contribution of parrotfish to the carbonate and sediment budgets of an atoll interior reef platform in the Maldives. We note that parrotfish erosion rates are high (6.3 kg m − 2 y − 1 ), generating large amounts of new coral-based sediment (2.6 kg m − 2 y − 1 ) that has a comparable grain size distribution to island deposits. Mean erosion rates by individual C. strongylocephalus (405 kg individual y − 1 ) were higher than C. sordidus (55 kg individual y − 1 ), but their contribution to erosion per unit area of reef was less due to a lower relative biomass ( C. strongylocephalus : 1.3 kg m − 2 y − 1 ; C. sordidus : 5.0 kg m − 2 y − 1 ). Parrotfish also facilitate sediment export from reefs (0.7 kg m − 2 y − 1 ), which contributes extensively to the development of the sand talus on the fore-reef slope and to the evolution of the wider atoll basin. Our results provide strong evidence that parrotfish erosion (and sediment generation) underpins island morphology on Maldivian reefs and highlight the importance of larger parrotfish as producers of island-grade sediment. Ecological processes must therefore be considered within future coastal management strategies for enhancing island stability. [ABSTRACT FROM AUTHOR]

Using coarse-scale approaches, existing national assessments of vulnerability and adaptation highlight physical land instability as a major threat to atoll island nationhood. However, such evaluations are bereft of detailed, ground-truthed analyses of the physical impacts of climatic change on reef islands, treating islands as homogenous in both biophysical and social characteristics. The distinct geomorphic context of two proximate reef islands (Jeh and Jabat) in the Marshall Islands was examined through conventional land survey techniques. A template documenting the nuances in island topography was used to evaluate simple inundation scenarios, reflecting current and future sea-level changes under storm surge conditions. The variations in local scale community exposure to inundation were discernible. The study highlights the importance of treating coarse-scale assessments with caution and underscores the need for continued commitment to resolving variations in community experiences to environmental change. Notions of risk and exposure are complex and embedded in both the biophysical and social contexts of each island community. Despite a number of targeted urban vulnerability studies in the Pacific there remains a need for efforts to document localised differences in experience to better inform contemporary adaptation efforts. [ABSTRACT FROM AUTHOR]

Liang, Y.; Kench, P.S., Ford, M.R., and East, H.K., 2016. Reef sediment supply and island building in the South Maldives. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 587-591. Coconut Creek (Florida), ISSN 0749-0208. Reef islands are small, low-lying islands composed mainly of bioclastic sands and gravels from the late Holocene. These islands, which support around 700,000 people, are vulnerable to potential threats including land submergence and shoreline erosion. Thus, the sediment supply of the surrounding coral reef is an important consideration for coastal maintenance but there is little research on the link between reef productivity and island building. This paper presents an examination of reef and island beach sediments (material and composition), as well as the eco-geomorphic zones of the contemporary reef. Two islands in Huvadhu Atoll of the Republic of Maldives were used in this investigation. Surficial sediment samples were collected from each reef zone, toe of beach, and beach berm for each island. Benthic surveys for each reef platform and aerial photo analyses were used to determine reef ecology and to constrain the eco-geomorphic zones on the reef. Prevalent organisms on both reefs were coral, crustose coralline algae, and Halimeda sp., while other sediment producers (molluscs and foraminifera) were less represented or absent. However, sediment samples taken from the reef flat show that all constituents are present, similarly to sand samples from the island beaches. The reef and beach sediments had similar compositions, suggesting that the island is still connected to the surrounding reef. This research provides insights into how these reef islands are maintained by the surrounding reef, which has implications for future island building and resilience to climate change. [ABSTRACT FROM AUTHOR]

Storms are important drivers of geomorphic change within atoll settings, causing rapid island erosion while also initiating island building through the generation of vast quantities of reef-derived sediment. Due to the combined effects of storms and sea-level rise, reef islands are thought to be on an erosional trajectory. Jaluit Atoll in the Marshall Islands was struck by Typhoon Ophelia in A.D. 1958, causing significant geomorphic change to reef islands. Using aerial photographs as well as recent satellite imagery we track the impacts of the typhoon and the multidecadal recovery of islands. Ophelia caused a significant reduction in total land area of Jaluit Atoll, from 9.95 km² to 9.45 km² (-5.1%), with islands on the northeast rim collectively reducing in size from 4.72 km² to 4.14 km² (-12.2%). Between 1976 and 2006, 73 of 87 islands increased in size, with the total landmass exceeding the pre-typhoon area (10.25 km²). However, we observe considerable spatiotemporal variability of impacts and relaxation following the typhoon. Results indicate that despite significant typhoon-driven erosion and a relaxation period coincident with local sea-level rise, islands have persisted and grown. [ABSTRACT FROM AUTHOR]

Reef islands are unique landforms composed entirely of sediment produced on the surrounding coral reefs. Despite the fundamental importance of these ecological-sedimentary links for island development and future maintenance, reef island sediment production regimes remain poorly quantified. Using census and sedimentary data from Vakkaru island (Maldives), a sand-dominated atoll interior island, we quantify the major sediment-generating habitats, the abundance of sediment producers in these habitats, and the rates and size fractions of sediment generated by different taxa. The estimated annual sediment production is 685,000 kg (or 370 m³), ~75% of which is produced on the narrow outer reef flat, despite composing only 21% of the total platform area. Approximately 65% of the platform acts solely as a sediment sink. Census data identify parrot- fish as the major sediment producers, generating >85% of the 5.7 kg m-2 of new sand-grade sediment produced on the outer reef flat each year. Halimeda (macroalgae) produce a further 10%, most as gravelgrade material. Comparisons between production estimates and sedimentary data indicate that reef ecology and island sedimentology are tightly linked; reef flat and lagoon sediments are dominated by coral and Halimeda, although fine- to medium-grained coral sand is the dominant (~59%) island constituent. The generation of sediment suitable for maintaining this reef island is thus critically dependent on a narrow zone of high-productivity reef, but most especially on the maintenance of healthy parrotfish populations that can convert reef framework to sand-grade sediment. [ABSTRACT FROM AUTHOR]

The geological stability and existence of low-lying atoll nations is threatened by sea-level rise and climate change. Funafuti Atoll, in the tropical Pacific Ocean, has experienced some of the highest rates of sea-level rise (~5.1 ± 0.7 mm/yr), totaling ~0.30 ± 0.04 m over the past 60 yr. We analyzed six time slices of shoreline position over the past 118 yr at 29 islands of Funafuti Atoll to determine their physical response to recent sea-level rise. Despite the magnitude of this rise, no islands have been lost, the majority have enlarged, and there has been a 7.3% increase in net island area over the past century (A.D. 1897-2013). There is no evidence of heightened erosion over the past half-century as sea-level rise accelerated. Reef islands in Funafuti continually adjust their size, shape, and position in response to variations in boundary conditions, including storms, sediment supply, as well as sea level. Results suggest a more optimistic prognosis for the habitability of atoll nations and demonstrate the importance of resolving recent rates and styles of island change to inform adaptation strategies. [ABSTRACT FROM AUTHOR]

Coral reef islands provide the only pedestals of human habitation in mid-ocean atoll archipelagoes. Understanding the environmental controls on island formation is critical for evaluating the future response of islands to environmental change and sea-level rise. This study examines the evolution of lagoonal reef islands in Huvadhoo atoll, southern Maldives. Using extensive ground penetrating radar (GPR) imaging of island sediment structure, combined with comprehensive analysis of island morphology, sedimentology, and 49 radiometric dates, detailed reconstructions of the evolution of two lagoonal islands is presented. A four-stage model shows a complex history of island formation across various stages of sea-level change during the late-Holocene: 1) lagoon infill occurring from ~3000–2000 years ago during a period of sea-level fall from the mid-Holocene highstand; 2) emergence of the island core through vertical aggradation during the latter stages of sea-level fall between ~2000 and 1500 yBP; 3) rapid lateral expansion of the islands between 1500 and 500 yBP coincident with the availability of sand-size sediments and during a period of sea-level oscillation; and, 4) subsequent minor expansion and modification of island shorelines through alongshore reworking of island sediments over the past 500 years. Results provide evidence of marked differences in the timing and mode of island formation within Huvadhoo atoll. Significantly, the formation of the lagoonal islands post-dates the formation of islands on the atoll rim by 1000–2000 years. Furthermore, the formation of sand islands over infilled shallow lagoons contrasts the formation of most atoll rim islands through the sequential deposition of storm-generated rubble deposited directly across reef surfaces that have reached their vertical growth limit. Results of lagoonal island formation in the southern Maldives provide comparative data for the northern Maldives. While the sequence of island formation follows the faro infill model identified in the northern archipelago, lagoonal islands in the south appear to have formed 2000 years after those in the north. This difference is likely to reflect lagged reef growth response from deeper foundations in the southern archipelago. [ABSTRACT FROM AUTHOR]

The impact of global environmental change on coral reef islands is uncertain, with few studies having resolved the critical controls on island formation and change. Based on detailed, topographic surveys, sediment analysis and radiometric dating, we present a multi-phase model of the formation of two reef islands in Jaluit atoll, Republic of the Marshall Islands. The initial phase of island building occurred 1300 years ago, later than elsewhere in the Marshall Islands and during a period of relative sea level fall from the mid-Holocene sea level highstand. Initial accumulation occurred as a consequence of relative emergence of the reef flat that forced a transition in reef flat ecology and dominant foraminifera sediment producers that contributed to island building. Distinctive sets of progradational ridges and their coarse sediment character provide evidence for the importance of extreme wave events in island expansion from an initial core. Expansion occurred in two principle phases, 650–350 years ago and 200 years ago to the present, each coincident with known phases of increased storminess in the central Pacific. Results highlight the complexity of island formation and show that future change will depend not only on sea level but storm processes that have been a major influence on island development over the past 650 years. Anticipated reduction in cyclogenesis in the southern Marshall Islands region suggests a near-future period of geomorphic stasis of the islands of Jaluit. An increase in cyclogenesis in the central Pacific and higher latitudes may enhance opportunities for storm-driven island accumulation events over the next century where coral growth is able to be maintained. • Island formation in Jaluit atoll occurred over the past 1300 years, during relative sea level fall and subsequent stability. • Cyclonic events were critical in the episodic expansion of islands over the past 700 years. • Relative sea-level fall forced changes in reef ecology and sediment production and transport regimes for island accumulation. • Formation of islands in Jaluit atoll lagged other parts of the archipelago and post-date habitation of the Marshall Islands. • Reduced storm dynamics in the tropical western north Pacific suggests a future period of island geomorphic stasis. [ABSTRACT FROM AUTHOR]

Recently developed Long (≥100 cm) axial field of view (AFOV) PET/CT scanners are capable of producing images with higher signal‐to‐noise ratio, or performing faster whole‐body acquisitions, or scanning with lower radiation dose to the patient, compared with conventional PET/CT scanners. These benefits, which arise due to their substantially higher, by more than an order of magnitude, geometric efficiency, have been well described in the recent literature. The introduction of Long AFOV PET/CT technology into the clinic also has important implications for the design and workflow of PET/CT facilities and their effects on radiation exposure to staff and patients. Maximising the considerable benefits of this technology requires a thorough understanding of the relationships between these factors to optimise workflows while appropriately managing radiation exposure. This article reviews current knowledge on PET/CT facility design, workflows and their effects on radiation exposure, identifies gaps in the literature and discusses the challenges that need to be considered with the introduction of Long AFOV PET/CT into the clinic. [ABSTRACT FROM AUTHOR]

Alcohol consumption is a major cause of cirrhosis and hepatocellular carcinoma (HCC). The prevalence of alcohol‐associated hepatocellular carcinoma (aHCC) varies worldwide but is highest in Eastern Europe. Alcohol is the second fastest‐growing cause of age‐standardized liver cancer mortality with tumors more often diagnosed outside surveillance protocols and at a more advanced stage. Risk factors for aHCC include greater amounts of alcohol consumption, sex, and certain genetic polymorphisms. Smoking, concomitant liver disease, obesity, and diabetes act synergistically in increasing the risk of HCC in alcohol‐associated liver disease. Alcohol‐related hepatocarcinogenesis results from the complex interactions of several mechanistic pathways. Although not completely understood, underlying mechanisms include acetaldehyde‐related hepatotoxicity, oxidative stress, activation of the innate immune system, and alterations of the host microbiome. [ABSTRACT FROM AUTHOR]

This study examines the clinical impact of E6AP and PML expression on prostate cancer progression. We identify an expression profile of high E6AP and low PML in human prostate cancer as a strong independent predictor of increased risk of biochemical recurrence, clinical recurrence and prostate cancer-specific death, independent of traditional clinicopathologic factors predicting recurrence.Background The promyelocytic leukemia (PML) tumor suppressor plays an important role in the response to a variety of cellular stressors and its expression is downregulated or lost in a range of human tumors. We have previously shown that the E3 ligase E6-associated protein (E6AP) is an important regulator of PML protein stability but the relationship and clinical impact of PML and E6AP expression in prostatic carcinoma is unknown. Methods E6AP and PML expression was assessed in tissue microarrays from a phase I discovery cohort of 170 patients treated by radical prostatectomy for localized prostate cancer (PC). Correlation analysis was carried out between PML and E6AP expression and clinicopathological variates including PSA as a surrogate of disease recurrence. The results were confirmed in a phase II validation cohort of 318 patients with associated clinical recurrence and survival data. Results Survival analysis of the phase I cohort revealed that patients whose tumors showed reduced PML and high E6AP expression had reduced time to PSA relapse (P = 0.012). This was confirmed in the phase II validation cohort where the expression profile of high E6AP/low PML was significantly associated with reduced time to PSA relapse (P < 0.001), clinical relapse (P = 0.016) and PC-specific death (P = 0.014). In multivariate analysis, this expression profile was an independent prognostic indicator of PSA relapse and clinical relapse independent of clinicopathologic factors predicting recurrence. Conclusion This study identifies E6AP and PML as potential prognostic markers in localized prostate carcinoma and supports a role for E6AP in driving the downregulation or loss of PML expression in prostate carcinomas. [ABSTRACT FROM AUTHOR]

The evolution, sedimentary structure and morphodynamics of Tepuka Island, a leeward vegetated sand cay on Funafuti atoll, Tuvalu, was examined based on morphostratigraphic analysis and radiometrically dated island sediments. Tepuka Island formed rapidly on the leeward reef platform between 1100 and 500 cal years BP and presents the first evidence of island formation at current sea level, postdating the Holocene highstand. The island is predominantly composed of foraminifera, coralline algae and coral sands derived from the surrounding reef flat. Morphostratigraphic analysis suggests that the island formed as a central core and prograded rapidly through incremental accumulation. Results indicate that the vegetated core of Tepuka has been stable since formation but the island margins have been morphologically dynamic. Over the past century the island has reduced in net area by approximately 23%. Substantial planform changes have been documented, which have occurred through differential erosion of the shoreline in two phases: lagoon shoreline erosion from 1897 to 1984 and; ocean shoreline coupled with extension of the terminal ends of islands from 1984 to 2011. Collectively, these changes have caused a lengthening and clockwise rotation of the island on the reef platform. The investigation highlights significant differences in the geomorphology, sediment composition, timeframe of formation and post-formation island dynamics compared with the storm deposited and comparatively stable motu on the exposed eastern atoll rim. [ABSTRACT FROM AUTHOR]

Sediment dynamics are an important control on the morphology and development of reef systems by actively removing and redistributing excess detrital sediment. This study presents quantitative data from direct point measurements of sediment transport on the platform surface and fore-reef slope of Vabbinfaru reef, North Malé Atoll, Maldives. A suite of sediment traps were used to construct actual rates of platform sediment fluxes and off-reef export over different spatial and temporal (seasonal) scales to establish key sediment transport pathways. Findings showed that high sediment fluxes occur on Vabbinfaru platform in the absence of major storm activity (up to 1905 g m-1 d-1), with 95% of annual transport occurring during the southwest monsoon as a result of increased wave energy. Climate-driven changes in the platform process regime caused a reversal of net sediment transport pathways between each monsoon season. Off-reef export rates were high, reaching a maximum of 12.58 kg m-1 y-1 for gravel and 407 g m-1 d-1 for sand-sized sediment. An estimated 127,120 kg is exported from the platform annually equating to a significant loss from the reef sediment budget and contributing to the long-term geomorphic development of the fore-reef slope and atoll basin. Detrital sediment reservoirs on Vabbinfaru are not purely depositional carbonate sinks, but rather temporary stores that are important in the transfer of sediment between reef zones. [ABSTRACT FROM AUTHOR]

Abstract: In 1905, a devastating typhoon hit Nadikdik Atoll (5°54′ N and 172°09′ E) in the southern Marshall Islands. Evidence suggests that large sections of reef islands on Nadikdik were overwashed and destroyed. Comparison of aerial photographs taken in 1945 and modern satellite imagery provides a unique record of the geomorphic adjustment of islands after the typhoon. Between 1945 and 2010 the vegetated area of islands on Nadikdik grew from 0.74 to 0.90km2. Observed changes to Nadikdik reef islands manifested through a range of styles and were largely accretionary. Of note, the formation of a new island was tracked from an embryonic deposit to a fully vegetated and stable island over a 61year period. Similarly, a number of previously discrete islands have agglomerated and formed a single larger island. These changes were rapid and indicate that reef island formation can occur quickly. Evidence suggests that despite the typhoon occurring over a century ago the geomorphic adjustment of islands is still on-going. [Copyright &y& Elsevier]

Abstract: This study examined coral reef platform wave processes and shoreline dynamics over short timescales. Wave energy gradients and shoreline change were measured over a 3-week period on Vabbinfaru platform, North Malé Atoll, Maldives, during the westerly monsoon in June 2010. Wave processes were measured using nine pressure sensors recording near continuous data for 19days around the reef and shoreline of a small circular sand cay. Toe of beach position was surveyed before, during and after the deployment to map changes in shoreline configuration. Results show that wave height and direction on the windward reef are closely controlled by local wind activity inside the atoll lagoon. Wave transformation across the platform was found to exhibit strong tidal modulation and results in distinct cross-reef energy zonation. Results are presented by comparing two contrasting boundary wind conditions: the first 2weeks characterised by moderate southwest winds, and the third week characterised by stronger northwest winds. Wave data was interpolated to platform scale and used to show spatial variations in energy exposure during the different boundary conditions. Under southwest winds, greatest wave energy was present on the western and leeward (eastern) reefs, driving an energy gradient towards the sheltered northern and southern shorelines. A net 4.5% increase in beach area was measured during this period. During stronger northwest winds, higher wave energy impacted the reef and was concentrated on the western reef, northern reef and northwest shoreline. An energy gradient formed around the island towards a low energy zone located at the southeast shoreline. Significant shoreline change occurred during this period with the toe of beach retreating landward by more than 10m on the northwest, northeast and southwest of Vabbinfaru Island. Beach area was reduced by 3761m2 (17%) as the shoreline was forced to adjust in response to a new hydrodynamic regime. Results show that the coral reef platform is able to modify and filter the incident wave climate, resulting in marked spatial differences in wave spectra. Spatial differences in wave energy are sensitive to local wind activity, resulting in rapid alteration in wave energy distribution around the platform. Results highlight that reef island shorelines are morphologically sensitive to short-term changes in boundary wind and wave conditions. Wave energy gradients driven by local wind activity have the potential to drive alongshore fluxes of sediment around island shorelines. Therefore, changes to the process regime can result in disequilibrium of the shoreline, forcing rapid adjustment of island sediment. [Copyright &y& Elsevier]

Faro are annular reefs, with reef flats near sea level and lagoons of variable depth, characteristic of both the perimeter and lagoons of Maldivian (Indian Ocean) atolls. Their geo- morphic development remains largely unknown, but where faro lagoons (termed velu in Maldivian) have infilled and support reef islands, these provide precious habitable land. Understanding the timing and modes of velu infilling is thus directly relevant to questions about reef island development and vulnerability. Here we use a chronostratigraphic data set obtained from a range of atoll-interior faro with partially to fully filled velu (including those with reef islands) from Baa (South Maalhosmadulu) Atoll, Maldives, to determine time scales and modes of velu infilling, and to identify the temporal and spatial thresholds that control reef island formation. Our data suggest a systematic relationship between faro size, velu infilling, and island development. These relationships likely vary between atolls as a function of atoll lagoon depth, but in Baa Atoll, our data set indicates the following faro-size relationships exist: (1) faros <~0.5 km² have velu that were completely infilled by ca. 3000 calibrated years B.P. (cal yr B.P.) with islands having established on these deposits by ca. 2.5 cal kyr B.P.; (2) faros >0.5 km² but <~1.25 km² have velu in late stages of infill, may support unvegetated sand cays and, given sufficient sand supply, may evolve into larger, more permanent islands; and (3) faros >~1.25 km² have unfilled (deeper) velu which might only infill over long time scales and which are thus unlikely to support new island initiation. These new observations, when combined with previously published data on Maldivian reef island development, suggest that while the velu of the largest faro are unlikely to fill over the next few centuries (at least), other faro with near-infilled velu may provide important foci for future reef-island building, even under present highstand (and slightly rising) sea levels. [ABSTRACT FROM AUTHOR]

This project was designed to harmonise the Royal College of Pathologists, College of American Pathologists and Royal College of Pathologists of Australasia datasets, checklists and structured reporting protocols for examination of radical prostatectomy specimens, with the aim of producing a common, internationally agreed, evidence-based dataset for prostate cancer reporting. The International Collaboration on Cancer Reporting prostate cancer expert review panel analysed the three existing datasets, identifying concordant items and classified these data elements as 'required' (mandatory) or 'recommended' (non-mandatory), on the basis of the published literature up to August 2011. Required elements were defined as those that have agreed evidentiary support at NHMRC level III-2 or above. Consensus response values were formulated for each item. Twelve concordant pathology data elements were identified, and, on review, all but one were included as required elements for tumour staging, grading, or prediction of prognosis. There was minor discordance between the three existing datasets for another eight items, with two of these being added to the required data set. Another 11 elements with a lesser level of evidentiary support were included in the recommended dataset. This process was found to be an efficient method for producing an evidence-based dataset for prostate cancer. Such internationally agreed datasets should facilitate meaningful comparison of benchmarking data, epidemiological studies, and clinical trials. [ABSTRACT FROM AUTHOR]

The Laurentide ice sheet was the largest late Pleistocene ice mass and the largest contributor to Holocene pre-industrial sea-level rise. While glaciological dates suggest final ice sheet melting between 8 and 6 ka, inversion of sea-level data indicates deglaciation at ca. 7 ka. Here, we present new chronostratigraphic constraints on Laurentide ice sheet disappearance based on Holocene relative sea-level observations from the tectonically stable north coast of Java, Indonesia. Age-elevation data from the flat upper surfaces of 13 fossil intertidal corals (i.e., microatolls) indicate that the Java Sea experienced a relative sea level of 1.3 ± 0.7 m above present between 6.9 and 5.3 ka. To determine uncaptured relative sea-level trends within the observational uncertainties of this apparently constant highstand, we analyzed the internal structure of three sliced microatolls from the same site to produce a high-resolution data set. These data were used to statistically model relative sea-level rates and trends. Employing the data with the model provided evidence for a short-lived rise of relative sea level from 1.0 ± 0.3 m above present at 6.7 ± 0.1 ka to 1.9 ± 0.3 m above present at 6.4 ± 0.1 ka. The end of this rise likely represents the last input of meltwater from the vast Laurentide ice sheet, which, consequently, collapsed at least 400 yr later than assumed by some widely used models of glacial isostatic adjustment. Incorporating these new results into such predictive models will help to better understand the geographical variability of future sea-level rise as a result of global warming. [ABSTRACT FROM AUTHOR]

Abstract: Skeletal extension, density and calcification rate of 12 scleractinian coral species comprising 7 morphological groups were examined on the reef crest of Vabbinfaru platform, Maldives. Growth rates of coral specimens were measured over the period of February 2010–March 2011 using alizarin staining and direct measurements. Skeletal extension rate was highly variable between coral species. Colony morphology was a major control on the skeletal extension and calcification of coral specimens. Growth rates of Acropora and Porites corals were comparable to existing data recorded for Caribbean and Indo-Pacific reef provinces. Skeletal density was less variable between species and was typically consistent among morphological groups. Findings represent the first estimates of coral growth in the central Indian Ocean region and add to the limited growth studies available that have examined a broad range of coral growth morphologies in other reef-building regions. [Copyright &y& Elsevier]

Abstract: An analytical model was constructed to simulate the refraction of waves on coral reef platforms comprising an idealised bathymetry of uniform depth and vertical reef faces. Model simulations were conducted to investigate the influence of key parameters such as reef shape and depth as well as wave period on the propagation behaviour of incident waves. Results of the refraction analysis demonstrate that different reef shapes produce characteristic patterns of wave convergence on reef surfaces. The location and stability of focal zones and hence wave convergence is largely controlled by the shape of platforms. Platform configuration further controls the distribution of wave energy across platform surfaces and determines the influence of incident wave forcing on different reef sections. Results have significant implications for sedimentation processes and hence the formation and stability of islands on reef platforms. Wave propagation patterns define sediment transport vectors and subsequently control the transport and deposition of different sized material. Platforms which promote marked wave convergence behaviour, such as elliptical and circular reefs, are more likely to retain sediment on reef surfaces, whereas narrow linear structures have a higher potential for the off-reef evacuation of sediment over leeward reef margins and the subsequent infill of deeper lagoonal areas. The study provides a physical basis for future investigations of reef hydrodynamics and platform sedimentation processes. [Copyright &y& Elsevier]

Waves are an important process responsible for the initiation and subsequent development of intertidal shore platforms. However, few field studies to date have described wave processes on shore platforms. A field experiment was conducted using an across-shore array of wave gauges, including a directional sensor, on a near-horizontal platform at Mahia Peninsula, North Island, New Zealand. Results show that the platform is very efficient in filtering wave energy at gravity wave frequencies (>0.05 Hz), with 40-80% reduction in wave height measured across the 140 m wide platform. By contrast, infragravity waves are present on the platform and increase in magnitude towards the cliff toe. Directional wave analysis indicates that wave reflection is mainly restricted to infragravity wave frequencies, demonstrating the differences in gravity and infragravity wave behaviour on the platform studied. Results indicate that, under fair weather conditions, the role of waves as an agent of cliff toe erosion is likely to be limited at present, although they are probably important for removing sediments accumulated at the cliff toe. The observed increase in infragravity wave energy towards the cliff toe implies that these long-period waves may be important geomorphic agents on shore platforms. [ABSTRACT FROM AUTHOR]

The generation and composition of carbonate sediment within tropical carbonate settings is controlled by the skeletal production of CaCO3 in conjunction with physical, biological and chemical processes which act to break down and disperse skeletal remains. Using the results of detailed tumbling barrel experiments, this paper discusses the role the physical durability of common constituents of reef sediment plays in the composition of coral reef deposits. The durability of the skeletal remains of six reef sediment constituents was determined experimentally using tumbling barrels. Results indicate that constituent durability varies considerably amongst common reef sediment constituents. Calcareous algae Halimeda was the least durable constituent tested, followed by larger benthic foraminifera Baculogypsina sphaerulata and Marginopora vertebralis and the pelecypod Fragum fragum. Two species of branching coral ( Acropora sarmentosa and Acropora nasuta) were found to be the most resistant to physical destruction. These findings provide increased power to interpret reef and island deposits and the potential role skeletal durability plays in the retention of constituent skeletons within coral reef associated sedimentary systems. [ABSTRACT FROM AUTHOR]