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Objective The aim was to assess the value of magnetic resonance cholangiopancreatography (MRCP) before endoscopic retrograde cholangiopancreatography (ERCP) in ultrasonographically and laboratory diagnosed obstructive jaundice. Background Obstructive jaundice is highly prevalent in Egypt, resulting in high morbidity, with increasing cost-burden. Numerous investigations are proposed for diagnosis of obstructive jaundice, such as ERCP and MRCP, with high sensitivity and specificity among other investigations, for diagnosing the cause of obstructive jaundice. However, ERCP is considered an invasive method that must be preserved as a life boat for therapy. Patients and methods A prospective randomized controlled study was conducted at General Surgery Department, Menoufia University Hospital, on 60 patients divided to two groups. First group patients underwent MRCP (30 patients) before ERCP, and the second group patients underwent ERCP only (30 patients). Results In the first group (MRCP±ERCP), scheduled ERCP was canceled in 10 patients of 30 patients (33.3%) owing to negative MRCP detection for stone or tumor. ERCP was done for 20 patients of 30 patients (66.6%), with successful intervention (94.7%) either in extraction of stone (in case of small stones) or stent placement (in large stones or tumors). In the second group, ERCP directly was done for 30 patients. Unnecessary ERCP was done for nine (30%) cases. Success intervention rate for ERCP in detection of stone or malignancy was 90.4%. This study showed a peak increase in accuracy, sensitivity, and specificity after addition of MRCP before ERCP in the diagnosis the cause of obstructive jaundice. Conclusion This study showed that MRCP before ERCP is very beneficial, decreases considerably the number of unnecessary ERCP, and decreases postoperative complications of ERCP. [ABSTRACT FROM AUTHOR]

The full thermodynamic study of the absorption refrigeration units requires the knowledge of the thermodynamic properties of the used mixture. The present work deals with the mathematical modeling of the thermodynamic properties of ammonia- water mixtures using various models. The presented model covers high vapor- liquid equilibrium pressures up to 110 bar and temperatures from 230 to 600 K. Furthermore, the calculation of the thermodynamic properties of the ammonia-water mixtures and their pure components was carried out. The obtained results were compared with results given in the literature. This shows a good concordance. [ABSTRACT FROM AUTHOR]

Background: Omentin-1 (intelectin-1) “a new adipokine described in 2003,” acts centrally to modulate the insulin resistance, body weight, and inflammation. However, its role in the liver pathogenesis and in the metabolic consequences of the liver disorders is not fully elucidated. Aim and objectives: the aim of the study was to assess the relation of serum omentin1 with fatty liver in obese and non-obese Subjects and methods: This was a comparative case control study was conducted at Ain Shams university hospital. Patients were divided in to two group: Group1: 40 patient 20 patient with fatty liver 10 of them obese and 10 non-obese compared with 20 not have fatty live 10obese and 10 non-obese, group 2. The duration of the study ranges from 6-12 months. Results: There was statistically significant difference between the four studied subgroups as regard Omentin1 and Apelin. There was statistically significant difference between group A and group B in obese as regard Omentin1 and Apelin. Conclusion: Omentin-1 might be considered as a protective factor in the evaluation of occurrence of NAFLD, especially in central obese patients. Thus, the measurement of these novel adipokines may contribute to the evaluation of NAFLD occurrence. [ABSTRACT FROM AUTHOR]

In this study, we investigate the chaotic behavior of fluid particles in three-dimensional open geometries and their effects on the amelioration of miscible fluids mixing, thermal homogenization and thermal performances by using a computational fluid dynamics (CFD) method. Three geometry configurations (straight channel, serpentine-2D channel and chaotic geometry channel serpentine-3D) are considered. The dispersion phenomena are characterized through the presentation of the Poincare sections and the mixing quality is quantified by calculating the mixing degree in cross section for several Reynolds numbers ranging from 5 to 200. This study reveals that height capacities in terms of mixing and heat performances are obtained by the chaotic geometry where the level mixing is superior to 0.95 for Reynolds equal to 200. In addition, the heat transfer in the S-3D is highly improved where the mean Nusselt number is 13 times bigger than that calculated in the straight channel. [ABSTRACT FROM AUTHOR]

This paper presents a study on energy performance of an earth air heat exchanger (EAHE) for buildings in Maghreb climatic context (Oran, Bechar and Adrar cities in Algeria). In order to check the influence of the material, two air conducts (one of galvanized sheet metal and the other in polyvinyl chloride–PVC) are considered under the same geometric conditions (a 20 m conduct length, 120 mm diameter and 2 m burial depth). They are used separately for the ventilation in simple current flow of two adjoining rooms constituting a test cell located at the university campus IGCMO-USTOMB (Oran, Algeria). An experimental device has been set up to measure the temperature at different points (air inlet/outlet air duct). Measurements were run in August 2015, and the monitoring of both exchangers allowed us to evaluate their cooling performance: 35.41% for the Zinc pipe and 58.42% for the PVC pipe. Experimental results were compared to those obtained from the simulation (under the Trnsys 16) and a fair similarity is obtained. In order to optimize the energy performance of the exchanger (EAHE), numerical simulations are carried out by varying different parameters: climate, burial depth, length and diameter of the duct. Other simulations have shown that the energy supplied by the cooling exchanger (EAHE) is more significant in the south of the country (Adrar and Bechar) than in the north (Oran). [ABSTRACT FROM AUTHOR]

Solar radiation is a renewable non polluting energy source which can be used in buildings through various systems technologies. Thermal radiation, absorbed or transmitted by the walls and windows, creates a solar gain which has a direct impact on the thermal behavior in the building. Most existing thermal models neglect the effect of the evolution of the sun patch position on the heating floor which can have a great impact on the indoor thermal comfort. In this paper, we present numerical model to calculate the transient sun patch position and its influence on the heating floor model in order to evaluate its impact on the heating floor operating conditions and on the indoor air temperature, which has a great influence on thermal comfort under the climatic conditions of Oran city in Algeria. The sun patch is calculated using Ray Tracing model as proposed in FLUENT whereas the room and the heating floor are modelled with TRNSYS software. Using literature data, the two proposed models (sun patch model and heating floor model) are validated and used to simulate the cases with different geographic locations and different window orientations, surfaces, and positions. Our results suggest that the displacement of the sun patch on the heating floor lead to a superheating of the irradiated zone and it affects the indoor air temperature and thermal comfort too. [ABSTRACT FROM AUTHOR]

This paper presents experimental and numerical studies of drop tests of corrugated cardboard packaging containing different foam cushions. An efficient homogenization model for the corrugated card- board has been developed. In our homogenized model, the corrugated cardboard is represented by a 2D plate. Instead of using a local constitutive law (relating the strains to the stresses) at each material point, the homogenization gives the global rigidities (relating the generalized strains to the resultant forces) for the equivalent homogeneous plate. This model was implemented into the FE software ABAQUS. The foam behaviour was experimentally determined and modelled using a crushable foam model of ABAQUS. The packages are tested in free fall from a given height on a rigid floor. The deceleration of the packed product was recorded using a triarial accelerometer. The numerical results obtained using the FE simulation with the homogenized model agree well with the experimental results. We have also shown that the contribution of the corrugated cardboard box to the shock response could not be neglected in the design of cushioning package. [ABSTRACT FROM AUTHOR]

• Novel comparative numerical study of non-Newtonian fluid mixing has been performed using efficient chaotic micromixers. • The TLCCM micromixer has shown its dominance due to its complex structure which generates more intense secondary flows compared to other micromixers. • High mixing index has been obtained using TLCCM micromixer, which exceeds 0.96 for all values of Reynolds number and power-law index. • The TLCCM micromixer has shown the lower pressure drops (Po/MI) compared to other considered micromixers. • Very low values of mixing energy cost (MEC) have been obtained using TLCCM micromixer. High-performances micromixers are widely used in various industrial applications. Mixing in the laminar regime and at low Reynolds numbers is of major importance in some processes. Implementing the physical phenomenon of chaotic advection to improve the mixing efficiency is a well-established technique, therefore, the secondary flows resulting from this technique are very intense and act at the microscopic level on homogenization. This study aims to compare different configurations of passive micromixers. The four examined micromixers are: Two-Layer Crossing Channels Micromixer (TLCCM), Semicircular Serpentine Micromixer (SCSM-90), Curved micromixer with Grooves (CG), and C-Shape micromixer. All micromixer geometries have the same hydraulic diameter and the equivalent unfolded length. The numerical simulations have been carried out at low Reynolds numbers using the CFD Fluent code to solve the 3D momentum equations, the continuity equation, and the species transport equation. The employed non-Newtonian shear-thinning fluids are the CMC solutions which are modeled by the power-law model with power-law index range from 0.73 to 1 and the generalized Reynolds number varies between 0.1 and 50. The mixing efficiency has been evaluated by calculating the mixing index (MI) based on the standard deviation of the mass fraction in different cross-sections. To examine the obtained results, the mass fraction distributions, the velocity profiles, and the mixing energy cost (MEC) have been presented. The results show that the TLCCM micromixer has a high mixing index which exceeds 0.96 for all the generalized Reynolds number values and the considered power-law index, it also has a lower mixing energy cost compared to other studied micromixers. [Display omitted] [ABSTRACT FROM AUTHOR]