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Antwerpen, Belgium
Antwerpen, Belgium

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Latif A.,Hashmat Medical and Dental College HMDC | Farhan M.A.,IMDC | Waliullah K.,IMDC
Medical Forum Monthly | Year: 2014

Objective: To study the presentation of varicose veins of lower limbs, treatment in our patients; and to see the causes of recurrent varicose veins at Islam Medical College, Sialkot, Pakistan. Study Design: Observational and descriptive study. Place and Duration of Study: This study was carried out at the Department of Surgery, Combined Military Hospital, Sialkot; from June 2007 to August 201 O.Department of Surgery, & Islam Teaching Hospital, Sialkot from September 2010 to September 2013. Materials and Methods: Adult patients referred by general practitioners with varicose veins of lower limb were included in the study. Data of sixty seven patients with varicose veins of lower limb was collected from June 2007 to September 2013. Patients were distributed in four groups depending upon the surgical procedures carried out. Full detailed history, examination, and investigations were done. Results of treatment were assessed by regular follow up. Data of only those patients was included who could complete follow up for at least 6 months. Results: Out of 67 patients included in our study, 25 cases were having recurrence; 8(32%) was recurrent cases from pervious surgeries from somewhere else and 17(68%) cases were diagnosed with recurrence after surgery at our hospitals. So, the incidence of recurrence in our cases exclusive remained to be 29%. Failure or recurrence in "Ligation" only was 38.5%, in ligation and reverse stripping was 30.7%, stab avulsions was 44.44% and in patients who underwent ligation, reverse stripping and stab avulsions was 12.5% after follow up of minimum 6 months. The patients are still on followup and the percentages are likely to increase with time as varicosities could be obvious. The anomalous double great saphenous veins, neovascularisation or missed tributaries of great saphenous vein during surgery and deep venous thrombosis before and after surgery were the most observed finding of recurrence. The recurrence of varicose veins was more in leg only as compared to both leg and thigh. Conclusion: Saphenofemoral ligation with below knee stripping and stab avulsions combined has the least frequency of recurrence, while Trendlenberg operation alone has the highest.


Winterwerp J.C.,Deltares | Winterwerp J.C.,Technical University of Delft | Wang Z.B.,Deltares | Wang Z.B.,Technical University of Delft | And 3 more authors.
Ocean Dynamics | Year: 2013

This is Part II of two papers on man-induced regime shifts in small, narrow, and converging estuaries, with focus on the interaction between effective hydraulic drag, fine sediment import, and tidal amplification, induced by river engineering works, e.g., narrowing and deepening. Paper I describes a simple linear analytical model for the tidal movement in narrow, converging estuaries and a conceptual model on the response of tidal rivers to river engineering works. It is argued that such engineering works may set in motion a snowball effect bringing the river into an alternative steady state. Part II analyses the historic development in tidal range in four rivers, e.g., the Elbe, Ems, Loire, and Scheldt, all in northwest Europe; data are available for many decades, up to a century. We use the analytical model derived in Part I, showing that the effective hydraulic drag in the Ems and Loire has decreased considerably over time, as anticipated in Part I. We did not find evidence that the Upper Sea Scheldt is close to its tipping point towards hyperturbid conditions, but risks have been identified. In the Elbe, tidal reflections against the profound step in bed level around Hamburg seem to have affected the tidal evolution in the last decades. It is emphasized that the conceptual picture sketched in these papers is still hypothetical and needs to be validated, for instance through hind-cast modeling of the evolution of these rivers. This will not be an easy task, as historical data for a proper calibration of the models required are scarce. © 2013 Springer-Verlag Berlin Heidelberg.


Tufail S.,S Z Medical College | Fatima A.,LMDC | Niaz K.,IM and DC | Qusoos A.,FM and DC | Murad S.,IMDC
Pakistan Journal of Medical and Health Sciences | Year: 2015

Back ground: Hyperlipidemia is one of the important risk factor to develop coronary artery disease (CAD) leading to main cause of morbidity and mortality due to heart attack and cardiac arrhythmias. Decreased level of plasma HDL-cholesterol independently can cause CAD. Recent studies have proved that walnuts can increase plasma HDL-cholesterol if taken in specific amount per day regularly Place and duration of study: Lahore General Hospital, Lahore from January 2014 to April 2014. Methodology: The baseline values of HDL-cholesterol were measured at day-0 and day-60 by separating other lipoprotein fractions using chemical precipitation with Mg2+, then coupling the products of a cholesterol oxidase reaction. Forty hyperlipidemic patients were selected from Lahore General Hospital for the study. Age of patients ranged from 20 to 65 years. Both gender male and female patients were enrolled. They were advised to discontinue any hypolipidemic medications and foods. Patients suffering from any metabolic disease, renal impairment, liver disease, and already having any cardiac problems were excluded from the research study. Forty patients were divided in two groups, twenty individuals in each group. Group-1 was advised to take 30 grams of walnuts (without shell) per day for the period of eight weeks. Group-II was considered as control group and was advised not to take any dry fruit including walnuts. Results: In twenty hyperlipidemic patients, two months therapy with 30 grams of walnuts per day increase in HDL-cholesterol was 6.3 mg/dl which was significant change when analyzed biostatistically, showing p-value <0.01. Statistical analysis: Mean values with SD and SEM were analysed statistically by using SPSS version 16.1. P-value of <0.001 was considered as significant and p-value of >0.05 was considered as non-significant change. Conclusion: It was concluded that regular intake of specific amount of walnuts without shell can increase good cholesterol (HDL-cholesterol) in male and female patients of age range from 18-65 yrs.


Decrop B.,Ghent University | Sas M.,IMDC | De Mulder T.,Ghent University | Toorman E.,Catholic University of Leuven
Proceedings WODCON XX - Congress and Exhibition: The Art of Dredging | Year: 2013

Dredging using Trailer Suction Hopper Dredgers (TSHD) with overflowing lean mixture can generate turbidity plumes in cases when fine sediment fractions are present in the pumped mixture. In view of the increased attention to environmental impacts of coastal and offshore dredging operations, research in this field is increasing. In this context the effect of turbidity generated by dredging activities plays an important role. The sediments brought in suspension can generate effects ranging from reduced light penetration in the water column over burial of sea bed ecosystems to dispersion of toxic materials attached to contaminated sediments. The dispersion of benthic material can have other impacts including siltation of still water bodies such as bays, docks or harbours. In the research programme of which this work is a part, laboratory experiments, numerical modelling and in situ measurements contribute to improving the knowledge on the behaviour of the near-field negatively buoyant fine sediment plume released from TSHD's. Based on scaled laboratory experiments, the effect of air bubbles and the presence of a schematised ship hull on the plume behaviour is assessed. This paper shows that both factors influence results in a significantly higher position of the plume compared to undisturbed cases and theoretical solutions of plumes in crossflow. Hence, simplified models for the prediction of the environmental impact of dredging plumes should incorporate these effects. © 2013 WODA.


Decrop B.,Ghent University | De Mulder T.,Ghent University | Toorman E.,Catholic University of Leuven | Sas M.,IMDC
Journal of Environmental Engineering (United States) | Year: 2015

Numerical simulations of the sediment-air-water buoyant jet released through the hopper dredgers' overflow shaft have been performed. The release of sediments into the marine environment due to skimming the excess water from the dredging vessel's hopper can lead to increased turbidity and adverse effects on the adjacent environment. Base-case simulations have been validated using in situ field observations. Simulations have been performed using the large-eddy simulation technique, which allows including the effect of large turbulent structures on the sediment dispersion. The complex nature of the flow field poses challenges for numerical simulations, such as the presence of propeller jets and three different phases: water, sediment, and air bubbles. The model has been applied to simulate the effect of a so-called environmental valve, which reduces air inclusion. This valve has been used in the past, but its efficiency as a function of the boundary conditions was never analyzed before. It is shown in this article that this type of valve can be very effective in reducing the generated turbidity, but only under given combinations of dredging speed, sediment concentration, overflow shaft diameter and overflow-stern distance. © 2015 American Society of Civil Engineers.


van Maren D.S.,Deltares | van Maren D.S.,Technical University of Delft | Winterwerp J.C.,Deltares | Winterwerp J.C.,Technical University of Delft | And 5 more authors.
Continental Shelf Research | Year: 2011

A new container dock in the Port of Antwerp, the Deurganckdok, was recently constructed in a location close to the Estuarine Turbidity Maximum (ETM) of the Scheldt River. In order to minimise sedimentation in the new dock, a Current Deflecting Wall (CDW) willbeconstructed. The aim ofthis paper isto assess the effect of the CDW on exchange flows and sediment fluxes. Determining this effect requires (1) understanding and reproduction of the sediment dynamics close to the Deurganckdok, and (2) accurate reproduction of the exchange flows between the dock and the Scheldt, and the effect of the CDW thereon. The sediment dynamics close to the Deurganckdok are dominated by a high concentration suspension (near-bed concentrations around 1 g/l) which is advected along the dock by the tidal currents. The sediment concentration is limited by the supply of sediment rather than the flow velocity. Most sediment will temporarily settle from suspension around slack tide. Hence, flood and ebb sediment concentrations are comparable, although the ebb and flood velocities are asymmetric. The peak sediment concentration occurs at the left or right bank of the Scheldt River, depending on the clockwise and counter-clockwise residual cross-channel currents. Exchange flows between the dock and the Scheldt are mainly a combination of horizontal eddies and salinity-driven flows, with velocities around 0.4 m/s. Most sediment enters the dock in a near-bed horizontal eddy, occurring around HW. The main effect of a CDW is a deflection of this sediment patch towards the river, reducing the sediment influx into the dock. The estimated reduction of siltation by the CDW is 18%. Alternative CDW configurations also reduce sedimentation in the dock, but less than computed with the design CDW. © 2010 Elsevier Ltd.


Waliullah K.,Islam Medical College | Farhan M.A.,IMDC | Latif A.,IMDC | Hamid A.,FMDC
Medical Forum Monthly | Year: 2014

Objective: This study was conducted to see the effect of intranasal splints in preventing post operative nasal synechia in patients who underwent intranasal surgery. Study Design: Observational and descriptive study. Place & duration of study: This study was carried out at the Department of ENT. Islam Teaching Hospital, affiliated to Islam Medical College, Pasrur road, Sialkot, Pakistan: from June 2007 to December 2013. Materials and Methods: Fifty four patients coming to Islam Teaching Hospital Sialkot from September 2012 to December 2013 were selected, lntransal splints were used in all patients after the intransal surgery. Nasal pack was removed on 1st or second post operative day. Intranasal splints were removed on 7th post operative day in the clinic without anesthesia. Follow up was done on 7th post operative day, 2 weeks and then monthly for 3 months. Results: In this study there were 36 cases (66.7 %) were among male patients and 18 cases (33.3 %) were among female patients. The Maximum age of the patients in this study was 45 years and minimum age of the patients was 9 years and mean age was 25.70. There were 2 cases (3.7 %) of septal abscess drainage, 2 cases (3.7 %) of septal hematoma drainage, 8 cases (14.8 %) of Septoplasty, 2 cases (3.7 %) septoplasty and bilateral partial inferior turbinectomy, 6 cases (11.1 %) of septoplasty plus bilateral partial inferior turbinectomy, 4 cases (7.4 %) of septoplasty plus left inferior turbinectomy & septoplasty plus manipulation of fractured nasal bones, 2 cases (3.7 %) of septoplasty plus nasal cauterization, 20 cases (37 %) of septoplasty plus right inferior turbinectomy, 2 cases (3.7 %) of septoplasty plus right inferior turbinectomy plus trimming of right middle turbinate & septoplasty plus right intranasal polypectomy. There were 10 patients (18.5 %) in which the nasal pack was removed on 1st day and 44 patients (81.5 %) in which nasal pack was removed on 2nd day. Conclusion: Intranasal splints made of intravenous fluid bottle soft plastic are well tolerated and they were effective in preventing nasal synechia formation.


Trouw K.,Fides Engineering | Gunst N.,Torgun | Moerkerke G.,Hylas | Schreel J.,Pauwels Consulting | And 3 more authors.
Proceedings of the Coastal Engineering Conference | Year: 2014

The new planned offshore windparks at the Belgian Continental Shelf have to be connected with the Belgian highvoltage electricity network (grid) developed by Elia. A possible way for this connection is the development of an island on which high voltage offshore substations are installed. These substations are connected with the wind farms and can transmit the electricity with a few common cables to land. This paper highlight some benefits and design aspects of this concept, together with design aspects of the cable installation.


Mercelis P.,IMDC | Dufour M.,GDF SUEZ | Gebelin A.A.,Gas Sayago | Gruwez V.,IMDC | And 3 more authors.
Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE | Year: 2014

For an offshore LNG project situated in the estuary of the Rio de la Plata nearby Montevideo, Uruguay, it was required to verify the deterministic design of the protective rubble mound breakwater and the jetty infrastructure with a level three probabilistic design. Therefore, in first instance extreme site conditions were required both in front of and behind the breakwater. To obtain these conditions, the first step is to extrapolate the offshore variables in order to translate them to the breakwater location. All the possible combinations of extreme wind, water level and waves are quantified with a probability of occurrence. A combination of univariate extreme value distributions, copula's and regression is used to describe the multivariate statistical behaviour of the offshore variables. The main variable is the wind velocity, as in the area of concern extreme wave conditions are wind driven. The secondary variable is water level. Wind velocity and water levels are only correlated for some wind directions. For these directions, wind velocity and water level extreme value distributions are linked through a multivariate Gumbel Copula. The wave height at the model boundaries was taken into account by a regression function with the extreme wind velocity at the offshore location and the wave period by a regression function with the wave height. This way 1515 synthetic events were selected and simulated with the spectral wave model SWAN, each of which a frequency of occurrence is calculated for. However, due to refraction and diffraction effects of the approach channel (in the area of concern water depths are limited to about 7 m and the navigation channel has a depth of about 14 m), the port basin and the breakwater itself, the spectral wave model SWAN is not sufficient to accurately calculate the local wave conditions in the entire area of interest. Therefore a non-linear Boussinesq wave model (i.e. Mike 21 BW) was set up in addition, using input from the spectral model at the boundary and including the navigation channel of more than 12 km long. Combining both models, significant wave heights are obtained on both the seaward side and the leeside of the breakwater with corresponding frequencies of occurrence. This approach allows the determination of conditional return periods and generates the site conditions required for a probabilistic level three design of the breakwater and the jetty infrastructure taking for example the joint probabilities between waves and water levels fully into account as needed for overtopping or failure calculations. Copyright © 2014 by ASME.


Trouw K.,Fides Engineering | Zimmermann N.,IMDC | Mathys M.,IMDC | Delgado R.,Flanders Hydraulics Research | Roelvink D.,UNESCO-IHE Institute for Water Education
Proceedings of the Coastal Engineering Conference | Year: 2012

A comparison between two very different numerical models is presented: Delft3D and XBeach. Delft3D (Deltares) calculates non-steady flow and transport phenomena that result from tidal and meteorological forcing. The wave propagation is calculated in the frequency domain. XBeach (Unesco-IHE, Delft University and Deltares) consists of formulations for short wave envelope propagation (time-dependent wave action balance), non-stationary shallow water equations, sediment transport and bed update. The model is able to resolve the time dependent long waves, which are important in the surf zone. A number of simplified cases are defined beforehand taking into account actual features and conditions existing in chosen problem areas. The examination of these simplified cases allows for the identification of driving processes and the assessment of the sensitivity to certain relevant parameters, with the advantage of working in scenarios of limited complexity and without excessive computational load.

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