Modelling the effects of sand extraction, on sediment transport due to tides, on the Kwinte Bank

In recent years, the exploitation of marine aggregates is increasing. As an example, on the Belgian continental shelf, one particular sandbank (the Kwinte Bank) is exploited extensively; this has led to the creation of a 5 m deep depression along its central part. In the present contribution, the influence of these bathymetric changes, on erosion and sedimentation patterns are studied, using numerical modelling, in order to obtain an initial impression of the effect of such intense sand extraction on the stability of the sandbank. Different numerical models are utilised. Twodimensional and three-dimensional hydrodynamic models have been used to derive currents, whilst third generation wave models have been used to simulate the waves. Two different models are presented, which calculate the total load sediment transport as a function of the local currents and waves. These models have been used to investigate the erosional and depositional patterns. The use of two different sediment transport models has some advantages, since the results of sediment transport models are still subject to some important uncertainties. The hydrodynamic model results are validated using ADCP current data, confirming the good performance of the models. Likewise the wave models provide good results, comparing their results with data from a buoy. The sediment transport model results were compared to the residual transport patterns, derived from the asymmetry of dunes. The results obtained seem to be in general agreement with these observations. The numerical models are used to simulate the response of the sediment transport to extensive sand extraction from the sandbank. One ‘worst-case’ scenario and two more realistic scenarios were simulated, whilst the effect of these bathymetric changes on sediment transport was studied. The results show that the intense sand extraction does not seem to influence extensively the stability of the sandbank, but that, as a consequence, there is less erosion and deposition. The model results show, for all of the scenarios, a small amount of deposition on the top of the sandbank; this could be an indication of a regeneration mechanism. A trench, created perpendicular to the crest of the sandbank, could be slowly refilled again. The time-scale of this regeneration and the influence of storms remain uncertain. Although the main emphasis of the paper relates to tidal forcing, a brief discussion is included on the influence of wave action, on sediment transport

Manipulating word awareness dissociates feed-forward from feedback models of language-perception interactions

Previous studies suggest that linguistic material can modulate visual perception, but it is unclear at which level of processing these interactions occur. Here we aim to dissociate between two competing models of language–perception interactions: a feed-forward and a feedback model. We capitalized on the fact that the models make different predictions on the role of feedback. We presented unmasked (aware) or masked (unaware) words implying motion (e.g. “rise,” “fall”), directly preceding an upward or downward visual motion stimulus. Crucially, masking leaves intact feed-forward information processing from low- to high-level regions, whereas it abolishes subsequent feedback. Under this condition, participants remained faster and more accurate when the direction implied by the motion word was congruent with the direction of the visual motion stimulus. This suggests that language–perception interactions are driven by the feed-forward convergence of linguistic and perceptual information at higher-level conceptual and decision stages

A large synoptic dataset of coastal in situ observations

Since the beginning of 2004 MUMM has performed a series of moorings in the Belgian Coastal Zone with a tripod or benthic lander, equipped with a series of oceanographic sensors. Current meters such as an Acous1c Doppler Profiler (ADP) and an Acoustic Doppler Velocimeter (ADV), a CT-­sensor capable of measuring temperature and salinity, op1cal (OBS) and acous1c backsca\er sensors (ADP and ADV) to measure suspended sediment concentra1on, a LISST 100 suspended par1cle sizer, a passive Cetacean monitoring device (C-­PoD) and a passive sampling device for chemical monitoring have ever since been moored for more than 1750 days. From autumn 2009 a permanent coastal observatory has been installed at MOW1, located to the west of the entrance to the Zeebrugge harbor. Other mooring sites include more offshore loca1ons, such as the Kwintebank, Gootebank, MOW0 and the offshore windmill farms and a very nearshore loca1on (Blankenberge)

The MELFO-Study:Prospective, Randomized, Clinical Trial for the Evaluation of a Stage-adjusted Reduced Follow-up Schedule in Cutaneous Melanoma Patients-Results after 1 Year

Guidelines for evidence-based follow-up in melanoma patients are not available. This study examined whether a reduced follow-up schedule affects: patient-reported outcome measures, detection of recurrences, and follow-up costs.This multicenter trial included 180 patients treated for AJCC stage IB-II cutaneous melanoma, who were randomized in a conventional follow-up schedule group (CSG, 4 visits first year, n = 93) or experimental follow-up schedule group (ESG, 1-3 visits first year, n = 87). Patients completed the State-Trait Anxiety Inventory, cancer worry scale, impact of events scale, and a health-related quality of life questionnaire (HRQoL, RAND-36). Physicians registered clinicopathologic features and the number of outpatient clinic visits.Sociodemographic and illness-related characteristics were equal in both groups. After 1-year follow-up, the ESG reported significantly less cancer-related stress response symptoms than the CSG (p = 0.01), and comparable anxiety, mental HRQoL, and cancer-related worry. Mean cancer-related worry and stress response symptoms decreased over time (p &lt;0.001), whereas mental HRQoL increased over time (p &lt;0.001) in all melanoma patients. Recurrence rate was 9 % in both groups, mostly patient-detected and not physician-detected (CSG 63 %, ESG 43 %, p = 0.45). Hospital costs of 1-year follow-up were reduced by 45 % in the ESG compared to the CSG.This study shows that the stage-adjusted, reduced follow-up schedule did not negatively affect melanoma patients' mental well-being and the detection of recurrences compared with conventional follow-up as dictated by the Dutch guideline, at 1 year after diagnosis. Additionally, reduced follow-up was associated with significant hospital cost reduction.</p

Detection of Melanoma Nodal Metastases; Differences in Detection Between Elderly and Younger Patients Do Not Affect Survival

Background. Melanoma lymph nodes metastases may be detected by patients or by physicians. Understanding the outcomes of self-detection or physician detection is essential for the design of follow-up studies. We evaluated the role of the method of detection in nodal disease in the prognosis of melanoma patients who underwent therapeutic lymph node dissection (TLND). Materials and Methods. All melanoma patients with palpable lymph nodes were included in a prospective database (n = 98), and the method of detection was recorded. Detection of lymph node metastases compared with pathological findings in the TLND was assessed by multivariate logistic regression. Disease-free survival (DFS) and disease-specific survival (DSS) were assessed by univariate and multivariate Cox proportional hazard analysis. Results. Nodal metastases were detected by physicians in 45% and by patients in 55% (P <0.001). Age was significantly associated with method of detection. Patients 60 years (odds ratio [OR] 0.3; P = 0.007). However, this was not associated with prognostic findings in TLND, number of positive nodes, tumor size, or extranodal spread. Method of detection or age at the time of nodal metastases was not significantly associated with 2-year DFS or DSS. Conclusions. 45% of all lymph node metastases in stage I-II melanoma patients are physician detected. Younger patients detect their own lymph node metastases significantly more often than elderly patients. However, neither the method of detection nor age correlates with DSS. More frequent follow-up would not alter DFS and DSS significantly

The MELFO Study:A Multicenter, Prospective, Randomized Clinical Trial on the Effects of a Reduced Stage-Adjusted Follow-Up Schedule on Cutaneous Melanoma IB-IIC Patients-Results After 3 Years

Background This study compares well-being, recurrences, and deaths of early-stage cutaneous melanoma patients in follow-up, as recommended in the Dutch guideline, with that of patients in a stage-adjusted reduced follow-up schedule, 3 years after diagnosis, as well as costs. Methods Overall, 180 eligible pathological American Joint Committee on Cancer (AJCC) stage IB-IIC, sentinel node staged, melanoma patients (response rate = 87%, 48% male, median age 57 years), randomized into a conventional (CSG, n = 93) or experimental (ESG, n = 87) follow-up schedule group, completed patient-reported outcome measures (PROMs) at diagnosis (T1): State-Trait Anxiety Inventory-State version (STAI-S), Cancer Worry Scale (CWS), Impact of Event Scale (IES), and RAND-36 (Mental and Physical Component scales [PCS/MCS]). Three years later (T3), 110 patients (CSG, n = 56; ESG, n = 54) completed PROMs, while 42 declined (23%). Results Repeated measures analyses of variance (ANOVAs) showed a significant group effect on the IES (p = 0.001) in favor of the ESG, and on the RAND-36 PCS (p = 0.02) favoring the CSG. Mean IES and CWS scores decreased significantly over time, while those on the RAND-36 MCS and PCS increased. Effect sizes were small. Twenty-five patients developed a recurrence or second primary melanoma, of whom 13 patients died within 3 years. Cox proportional hazards models showed no differences between groups in recurrence-free survival (hazard ratio [HR] 0.71 [0.32-1.58]; p = 0.400) and disease-free survival (HR 1.24 [0.42-3.71]; p = 0.690). Costs per patient after 3 years (computed for 77.3% of patients) were 39% lower in the ESG. Conclusion These results seemingly support the notion that a stage-adjusted reduced follow-up schedule forms an appropriate, safe, and cost-effective alternative for pathological AJCC stage IB-IIC melanoma patients to the follow-up regimen as advised in the current melanoma guideline

Non-adherence to consensus guidelines on preoperative imaging in surgery for primary hyperparathyroidism

Objective: The aim of this study was to determine the adherence to consensus guidelines on preoperative imaging of patients with primary hyperparathyroidism (pHPT) in real local practice. Methods: This was a retrospective multicenter cohort study of 411 patients undergoing parathyroidectomy for pHPT from 2007 to 2017 in three referral centers. Results: In 286/411 patients (69%) the preoperative imaging workup adhered to guidelines (utilizing ultrasound and parathyroid scintigraphy). In patients in whom guidelines were followed 63% were discharged within one day versus 37% in whom guidelines were not followed (P< .0005). The use of a bimodality imaging workup, starting with ultrasound and parathyroid scintigraphy followed by imaging upscaling aiming for anatomical and functional concordance, was a predictor for the performance of a minimally invasive parathyroidectomy (OR 4.098, 95% CI 2.296-7.315,P< .0005). Conclusion: The level of compliance to preoperative imaging guidelines is suboptimal in this population. Patients in whom adherence was achieved showed a shorter length of stay. More education of physicians is required regarding the appropriate preoperative imaging workup in pHPT