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During several monitoring campaigns in the Scheldt estuary, ADCP’s (acoustic Doppler current profilers) are deployed to measure the water velocities and discharges. The acoustical backscatter intensity of the ADCP’s are commonly used to estimate the suspended sediment load. When the measurement platform with down-looking ADCP is kept stationary, the bottom tracking measurement principle can be used to detect and estimate the bed load transport. However, the measurements of the bottom tracking is experimental. To assess the uncertainty of these measurements, a flume (W = 1.2 m, L = 25 m and H < 1m) was built to create controlled flow conditions, several bed materials are used. As a reference measurement of the total bottom transport, a weigh cell was constructed at the end of the flume.ADCP's (different types) are installed above the sand bed. Measurements of bed load transport velocity from the bottom tracking feature are performed. Different settings of the instruments are tested and compared, together with a range of flow regimes. Also optical measuring techniques (camera’s, turbidity sensor) are used, both down-looking and side-looking. The side-looking cameras are installed to map the depth (and also velocity) of the mobile layer above the bed. Down-looking cameras are installed to look in a restricted view area to follow the individual sediment grains in the bottom-top layer. Combining, the pictures with PIV or PTV algorithms, the velocity of the individual sediment grains can be detected. The different measurement techniques are compared.

Within the framework of the cross-border Flemish-Dutch research program, Agenda for the Future (Agenda voor de Toekomst), field measurements were collected and calibrated at a number of strategic locations along the Schelde. This report describes a April and May 2016 field campaign to measure hydrodynamics and sediment transport near the sill of Hansweert (Drempel van Hansweert).Four up-looking ADCPs were placed on the bed and left to measure currents and acoustic backscatter over a period of one month. Due to the dynamic nature of the location, all four ADCPs were buried in sand by the end of the campaign, but were able to collect between 5 and 28 days of data. In order to estimate sediment transport rates using the acoustic backscatter of the ADCPs, two 6-hour calibration campaigns were conducted on May 9th and 10th, respectively. During the calibration, currents, suspended sediment concentration, sediment transport, and grain size were measured using an ADCP, LISST, two Delft bottles, and by collecting water and sediment samples for lab analysis. One of the ADCPs was already covered with sand at the time of the calibration campaign, but the other three ADCPs were calibrated to produce a time series of currents and sediment transport.This report presents the measurement techniques, calibration methods, and summary of results (including ambient conditions). Accompanying this report are time series of hydrodynamic and sediment transport measurements from the four bed-mounted ADCPs. The results from this campaign (and others) are being used to calibrate and validate numerical models, the results of which will be described in a later report.

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). 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.

Due to the complex nature of mud consolidation within harbours, a robust and accurate guideline to evaluate the nautical depth is still under debate. Besides, alternative dredging techniques (e.g. mud conditioning/fluidising) have proven to be an applicable method to reduce dredging costs in a number of harbours. Yet, before one can define new criteria for nautical depth or implement new dredging techniques, a deeper understanding of the temporal evolution of rheological, mechanical and biological characteristics of mud is needed. In this study, we aim to improve the understanding of the rheological properties of consolidating mud by comparing the consolidation process of mud from 5 different locations namely the harbours of Zeebrugge (ZB) and Deurganckdok (DG) in Belgium, the harbours of Rotterdam (RO) and Ijmuiden (IJ) in the Netherlands and the Emden (EM) harbour in Germany. The main objectives of this project are to examine the effect of the consolidation process on the mechanical, rheological and biological characteristics of mud as well as to explain the differences in consolidation processes between muds from different origins.This sub-report describes the properties of different mud types used for the experiments as well as the experimental setup. The experimental setup includes a detailed description of the governing parameters, experimental design and measurement techniques conducted on two different consolidation columns, small and large.

In an initial study it was shown that (without hormonal influences) middle-aged (premenopausal) women show a smaller frequency and intensity range and a lower fundamental frequency of the voice compared to young women. To investigate the impact of menopause on voice and nasal resonance a cross-sectional non-randomized study design was used. Vocal characteristics and nasal resonance in premenopausal and postmenopausal women without hormone therapy (HT) were compared. Postmenopausal women without HT showed a significantly lower speaking fundamental frequency (SFF) and were able to phonate lower compared to postmenopausal women with HT. The mean difference in SFF was 14 Hz. HT can also counteract the menopausal changes in SFF. The lower SFF did not result in vocal complaints. Further research about the impact of menopause and HT on voice should concentrate on elite professional voice users.

The Sediment Test Tank (STT) has been built on the terrain of Flanders Hydraulic Research (FHR) to host in-situ sediment for sediment studies. After delivery (16/04/2009) of 50 m³ of sediment from the harbour of Zeebrugge at a density of 1.14 m³/s, sedimentation and consolidation created vertical differences in the sediment in the STT. The measurements started on 21/04/2009. This report deals with the measurements until 26/05/2010.A whole range of parameters have been measured over time and depth to monitor the sediment characteristics as much as possible. Some parameters are measured in situ in the tank, e.g. measurements by the YSI-multiparameter probe and pore pressure measured by piezometric tubes. Other parameters are measured on undisturbed samples, e.g. density, rheological parameters and thermo-gravimetric analysis. This report gives the findings of the measurements and recommendations for further measurement campaigns in the STT.

The dimensional analysis technique was applied in order to determine possible relationships between the measured parameters in the STT and to identify possible inconsistencies in the measurements.The present dimensional analysis focuses only in the sedimentation and consolidation processes.Relationships between parameters could be used to identify inconsistencies for measured pore pressure, effective stresses and density values. Recommendations are suggested for sampling points and measuring methods.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by biased Th2 inflammation and CRS without nasal polyps (CRSsNP) by a Th1 immune response. Colonization by Staphylococcus aureus is increased in CRSwNP. We aimed to determine macrophage phenotypes in nasal mucosa of CRSwNP and CRSsNP and to examine phagocytosis of S. aureus in these pathologies.Macrophage phenotyping was performed by immunohistochemical staining on nasal mucosa sections from 28 patients; in addition flow cytometry analysis was performed. Tissue homogenate protein levels of IFN-γ, IL-5, IL-6, IL-1β, TGF-β, eosinophil cationic protein (ECP) and total IgE were analyzed and correlated with macrophage subtypes. Phagocytosis of S. aureus was analyzed by flow cytometry. Survival of S. aureus in Thp1 cells in the presence of polarizing cytokines was studied in vitro. By immunohistochemical analysis more M2 macrophages were present in CRSwNP than in CRSsNP. This also was positively correlated with increased levels of IL-5, ECP and locally produced IgE and decreased levels of IL-6, IL-1β and IFN-γ. FACS analysis of dissociated nasal tissue confirmed the presence of increased numbers of M2 macrophages (CD206(+) HLADR(+) CD14(+) CD11c(+) CD20(-) ) in CRSwNP as compared to controls, while the number of M1 macrophages (CD206(-) HLADR(+) CD14(+) CD11c(int) CD16(-) CD20(-) ) was not different. Phagocytosis of S. aureus by human tissue derived macrophages was reduced in CRSwNP as compared to macrophages from the control inferior turbinates. Decreased phagocytosis of S. aureus and an M2 activation phenotype in CRSwNP could potentially contribute to persistence of chronic inflammation in CRSwNP.