9 research outputs found

    Local-scale post-event assessments with GPS and UAV-based quick-response surveys:A pilot case from the Emilia-Romagna (Italy) coast

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    Coastal communities and assets are exposed to flooding and erosion hazards due to extreme storm events, which may increase in intensity due to climatological factors in the incoming future. Coastal managers are tasked with developing risk-management plans mitigating risk during all phases of the disaster cycle. This necessitates rapid, time-efficient post-event beach surveys that collect physical data in the immediate aftermath of an event. Additionally, the inclusion of local stakeholders in the assessment process via personal interviews captures the social dimension of the impact of the event. In this study, a local protocol for post-event assessment, the quick-response protocol, was tested on a pilot site on the Emilia-Romagna (Italy) coast in the aftermath of an extreme meteorological event that occurred in February 2015. Physical data were collected using both real-time kinematic Geographical Positions Systems and unmanned aerial vehicle platforms. Local stakeholders were interviewed by collecting qualitative information on their experiences before, during, and after the event. Data comparisons between local and regional surveys of this event highlighted higher data resolution and accuracy at the local level, enabling improved risk assessment for future events of this magnitude. The local survey methodology, although improvable from different technical aspects, can be readily integrated into regional surveys for improved data resolution and accuracy of storm impact assessments on the regional scale to better inform coastal risk managers during mitigation planning

    Vegetation effects on coastal foredune initiation: Wind tunnel experiments and field validation for three dune-building plants

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    As the land-sea interface, foredunes buffer upland habitats with plants acting as ecosystem engineers shaping topography, and thereby affecting storm response and recovery. However, many ecogeomorphic feedbacks in coastal foredune formation and recovery remain uncertain in this dynamic environment. We carried out a series of wind tunnel experiments testing how the morphology, density, and configuration of three foredune pioneer dune building plant species influence the most basic stage of dune initiation — nebkha formation around individual plants. We established monocultures of native Ammophila breviligulata and Panicum amarum and invasive Carex kobomugi in 1 m × 1 m planter boxes of sand to simulate approximate natural and managed densities and planting configurations on the US Mid-Atlantic coast. We subjected each box to constant 8.25 m/s wind for 30 min in a moveable-bed unilateral-flow wind tunnel with an unvegetated upwind sand bed. We quantified resulting topography with sub-millimeter precision and related it to plant morphology, density, and configuration. Plant morphology, density, and configuration all influenced the resulting topography. Larger plants produced larger nebkha with greater relief, height, and sand volume. However, nebkha area, height, and planform shape varied among species, and taller plants did not necessarily produce taller nebkha. The erect grasses, Ammophila and Panicum, produced more elongated, high-relief nebkha compared to the low-lying Carex, which produced lower and more symmetrical equant nebkha. A staggered planting configuration produced greater net sediment accumulation than non-staggered. We validated these results against high-resolution field topographies of foredune nebkha and found strong agreement between the datasets. Our results provide species-specific parameters useful in designing foredune plantings and beach management and can be used to parameterize vegetation in models of foredune evolution associated with different plant species. By first understanding the underlying ecogeomorphic feedbacks involved in nebkha formation, we can more effectively scale up to forecast coastal foredune evolution and recovery

    HBV Life Cycle: Entry and Morphogenesis

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    Hepatitis B virus (HBV) is a major cause of liver disease. HBV primarily infects hepatocytes by a still poorly understood mechanism. After an endocytotic process, the nucleocapsids are released into the cytoplasm and the relaxed circular rcDNA genome is transported towards the nucleus where it is converted into covalently closed circular cccDNA. Replication of the viral genome occurs via an RNA pregenome (pgRNA) that binds to HBV polymerase (P). P initiates pgRNA encapsidation and reverse transcription inside the capsid. Matured, rcDNA containing nucleocapsids can re-deliver the RC-DNA to the nucleus, or be secreted via interaction with the envelope proteins as progeny virions

    Pro-apoptotic and antiproliferative activity of human KCNRG, a putative tumor suppressor in 13q14 region

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    Deletion of 13q14.3 and a candidate gene KCNRG (potassium channel regulating gene) is the most frequent chromosomal abnormality in B-cell chronic lymphocytic leukemia and is a common finding in multiple myeloma (MM). KCNRG protein may interfere with the normal assembly of the K+ channel proteins causing the suppression of Kv currents. We aimed to examine possible role of KCNRG haploinsufficiency in chronic lymphocytic leukemia (CLL) and MM cells. We performed detailed genomic analysis of the KCNRG locus; studied effects of the stable overexpression of KCNRG isoforms in RPMI-8226, HL-60, and LnCaP cells; and evaluated relative expression of its transcripts in various human lymphomas. Three MM cell lines and 35 CLL PBL samples were screened for KCNRG mutations. KCNRG exerts growth suppressive and pro-apoptotic effects in HL-60, LnCaP, and RPMI-8226 cells. Direct sequencing of KCNRG exons revealed point mutation delT in RPMI-8226 cell line. Levels of major isoform of KCNRG mRNA are lower in DLBL lymphomas compared to normal PBL samples, while levels of its minor mRNA are decreased across the broad range of the lymphoma types. The haploinsufficiency of KCNRG might be relevant to the progression of CLL and MM at least in a subset of patients

    Quantifying Estuarine Hydrometeorological Coastal Hazards Using a Combined Field Observation and Modeling Approach

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    Coastal development and its associated site management have rapidly expanded to estuarine environments while continuing to increase worldwide. With the growth of coastal management projects, field observations are required to understand how anthropogenic construction, coastal defense, environmental restoration, and conservation areas will react to the typical, extreme, and long-term conditions at the proposed sites. To address these unknowns, we present a multi-faceted coastal risk assessment of a unique, recently nourished estuarine beach near the mouth of the Delaware Bay Estuary by merging rapid-response remote sensing platforms, hydrodynamic models, and publically available monitoring datasets. Specifically, hydrometeorological events from 2015 to 2019 were the focus of peak-over-threshold statistics, event type definition, and clustered event interval determination. The 95th percentile thresholds were determined to be the following: 0.84 m for the significant wave height, 13.5 m/s for the 10-m elevation wind speed, and 0.4 m for the total water level residuals. Tropical and extra-tropical cyclones, light gales, or cold and stationary fronts proved to be the meteorological causes of the sediment mobility, inducing the hydrodynamics at the site. Using these event types and exceedance instances, clustered meteorological events were defined as having an interval greater than twelve hours but less than five days to be considered clustered. Clustered events were observed to cause greater volumetric change than individual events, and are currently underrepresented in coastal risk planning and response in the region. Coastal monitoring field measurements should consider clustered events when conducting post-hazardous or erosional event response surveys. This work highlights the importance of clustered hydrometeorological events causing estuarine coastal risk, and how to quantify these effects through combined field observations and modeling approaches
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