Evidence for a Phosphorylated Form of Calmodulin in Chicken Brain and Muscle

Phosphocalmodulin (PCaM) was identified after analysis of calmodulin (CaM) preparations by two-dimensional gel electrophoresis by using a modified ampholyte system to resolve very acidic proteins. The analysis of CaM prepared by the conventional procedure based upon its heat resistance and acidity as well as the analysis of whole urea extracts from brain showed that PCaM was a major component in this tissue. PCaM was 1 pH unit more acidic than CaM, and its electrophoretic mobility, unlike CaM, was not changed by either calcium or ethylene glycol-bis(β-aminoethyl ether)-N,N-tetraacetic acid. In urea extracts of brain prepared in buffers containing phosphate and sodium fluoride, PCaM was as prominent as CaM; it was partially converted into CaM after elution from the gel and reelectrophoresis. Amino acid analysis of PCaM and CaM purified by two-dimensional gel electrophoresis showed the same composition for the two proteins, including their trimethyllysine content. Incorporation of (^32)P occurred exclusively into the acidic variant when brain slices were incubated with (H_3)(^32(PO_4)); amino acid analysis showed that the phosphate was bound to serine residues. CaM was found also to be phosphorylated in vitro by a phosphorylase kinase preparation from skeletal muscle

Analysis of multibeam echo sounding data on bed forms near the Walsoorden sandbar, a first phase in the subtidal habitat classification for the Western Scheldt

River morphodynamics and sediment transportRiver morphology and morphodynamic

Sediment transport in the Schelde-estuary: a comparison between measurements, transport formula and numerical models

ABSTRACT The Schelde-estuary serves different estuarine functions and therefore faces managers with multiple challenges: increasing tidal propagation vs. safety against flooding; sedimentation in the navigation channel vs. port accessability; changing dynamics vs. ecology. Within the Flemish-Dutch Long Term Vision for the Schelde-estuary, a 4 year (2014)(2015)(2016)(2017) research programme was defined, in which 8 topics will be dealt with (e.g. tidal penetration, risk for regime shift, sediment strategies, valueing ecology). Two fundamental tools will be crucial in answering the different questions towards the future management of the estuary: expertise/system understanding and numerical models. At this moment (first year), several projects are ongoing trying to increase the system understanding and improving the state-of-the-art numerical models. Where the numerical models reproduce the hydrodynamics reasonably well, sediment transport and the resulting morphological changes is still a big challenge. Therefore an extensive monitoring campaign was performed in 2014, during which both hydrodynamic and sediment transport measurement were performed in the Schelde-estuary. At more than 10 locations, from the up-estuarine part (Boven-Zeeschelde) to the mouth area (Vlakte van de Raan), measurements were executed over a full tidal cycle (13h). Currents were measured using ADCP, while sediment transport was measured using both direct (Delft Bottle and pump samples) and indirect (OBS, ABS) techniques. This extensive dataset allows an in-depth analysis of the sediment transport processes occuring in the estuary. A comparison will be made with several transport formula (e.g. Bagnold, Engelund-Hansen, Van Rijn, ...). The data will also be used to validate the existing numerical models, allowing a better assesment of the possibilities and limitations of the present numerical models. KEY WORDS Sediment transport, measurements, numerical modelling, estuary THE SCHELDE-ESTUARY The Schelde-estuary is a macro-tidal estuary with a length of 180 km in Flanders and the southern part of the Netherlands The estuary is characterised by semi-diurnal tides, causing ebb and flood currents with important sediment transports of both cohesive as non-cohesive sediments. The Schelde-estuary serves different estuarine functions and therefore faces managers with multiple challenges: increasing tidal propagation vs. safety against flooding; sedimentation in the navigation channel vs. port accessability; changing dynamics vs. ecology. Within the Flemish-Dutch Long Term Vision for the Schelde-estuary, a 4 year (2014-2017) research programme was defined, in which 8 topics will be dealt with (e.g. tidal penetration, risk for regime shift, sediment strategies, valueing ecology). METHODOLOGY In order to supply managers with adequate answers, research tools (both expertise/system understanding and numerical model

2D modeling of tidal wave propagation through a large vegetated marsh

Water Qualit

A Sand Transport Model for the Scheldt Estuary: The 3D Scaldis Sand Model

A sand transport model for the Scheldt estuary, located in the Netherlands and Belgium, based on the hydrodynamic 3D Scaldis model is presented in this paper. The objective is to model only non-cohesive sediment transport. The model is validated using field measurements performed with a Delft bottle at different locations along the estuary. Asymmetry of the cross sectionally averaged flow velocity is used to understand the results of the sand model in terms of net sand transport direction

HISTORICAL EVOLOTION OF MUD DEPOSITION AND EROSION IN INTERTIDAL AREAS OF THE SCHELDT ESTUARY (BELGIUM AND SW NETHERLANDS)

ABSTRACT The mud dynamics in an estuary are recognized as an important element of estuarine functioning, because increasing suspended sediment concentrations may be both harmful for ecological functions (e.g., biomass production by phytoplankton) and deteriorative for human functions (e.g., by siltation of shipping channels). Considering the potential risk of increase in suspended sediment concentration in the Schelde estuary, this study aims to quantify the mud deposition/erosion in different time periods since 1930 to present, different intertidal ecotope types, and different zones along the Schelde estuary, including the Westerschelde and Zeeschelde. We analyzed the height change, volume change, eroded or deposited mud mass, and the overall mud balance. Our results suggested that net mud deposition occurred in intertidal areas in both the Westerschelde and Zeeschelde in almost all time periods. The mud deposition in stable marshes plays an important role. A large amount of mud deposition is also observed in stable intertidal flats and areas that shifted from intertidal flat to marshes or from subtidal zone to intertidal flat. Over 90% of mud erosion is observed in areas that shifted from intertidal flat to subtidal zone. Mud erosion is also observed in areas that shifted from marsh to intertidal flat

A 2Dh Hydrodynamic Model of the Scheldt Estuary in 1955 to Assess the Ecological Past of the Estuary

Water Qualit

Sediment transport modelling (TELEMAC-3D + GAIA) case study: sand disposals in the Western Scheldt

Hydrodynamic

Validation of a 2-dimensional hydrodynamic model within a study to propose the optimal disposal strategy in the Western Scheldt

In order to work out a disposal strategy along sandbars in the Western Scheldt, Flanders Hydraulics Research conducted research combining field measurements and 2D high resolution numerical modelling. The Delft3D software was used for this. For the calibration of the numerical model, a lot of information and experience from previous modelling studies was available. In a first phase, the water levels in the model were calibrated by applying a space varying Manning bed roughness coefficient: in this way the propagation of the tidal wave between the different measurement stations could be adapted in the model. In a second phase, the focus of the calibration was on the flow velocities. The horizontal viscosity was used for this as the main parameter. For the intertidal area, the maps of ecotopes were used to calibrate the flow velocity. A depth depending bed roughness as well as the critical velocity between high and low dynamic intertidal areas were used for the calibration. Combining the in situ measurements, the calibrated numerical models and the experience from 2 in situ disposal tests, the engineers of Flanders Hydraulics Research succeeded in working out an optimal disposal strategy