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Surgical Treatment of Giant Cavernous Hepatic Haemangiomas  [PDF]
Ibrahim Abdelkader Salama, Mohammed Hussein Abdullah, Mohammed Houseni
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.38081
Abstract: Background: Haemangiomas are the most common benign liver tumors. Treatment is indicated for symptomatic tumors, rapid increase in size, rupture or doubt in diagnosis. Objective: Evaluation the efficacy of surgical treatment of giant cavernous hepatic haemangioma in tertiary hepatobiliary center. Patients and Methods: Retrospective study of 34 patients with giant hepatic haemangioma operated upon. The diagnosis was proved preoperatively in 27 patients and confirmed by histopathology postoperatively in all patients. The indication of surgery was abdominal pain with large sizes tumors, rapid growth, and spontaneous rupture with haemoperitoneum. Surgical treatment either liver resection or living liver transplantation. Results: 23 cases (67.6%) were females & 11 cases (32.4%) were males, median age 38.8 years. Haemangiomas located in right lobe in 19 patients (55.9%), left lobe in 12 patients (35.4%) in both lobe in 2 patients (5.8%), scattered all over both lobe in one patient (2.9%), solitary in 27 cases (79.4%) and multiple in 7 patients (20.6%). The diameter was 8 - 27 cm, mean 18.6 cm in diameter. 33 patients had liver resection (29 elective resection and 4 emergent resection for rupture). One patient had haemangioma irresectable; the living liver transplant was performed. No mortality during 18 months follow up and complication occurred in 8 patients out of 34 patients. Conclusion: Hepatic resection is an effective treatment option for giant cavernous hepatic haemangioma, in selected patient living related liver transplantation may be the only therapeutic option.
Interference Mitigation MAC Protocol for Cognitive Radio Networks  [PDF]
Nasir Faruk, Maaruf Ali, Mohammed Ibrahim Gumel
Wireless Engineering and Technology (WET) , 2012, DOI: 10.4236/wet.2012.32010
Abstract: The growing demand for wireless services coupled with the limited availability of suitable electromagnetic spectrum is increasing the need for more efficient RF spectrum utilization. Spectrum allocated to TV operators can potentially be shared by wireless data services, either when the primary service is switched off or by exploiting spatial reuse opportunities. This paper describes a dynamic spectrum access scheme for use in the TV bands which uses cognitive radio techniques to determine the spectrum availability. The approach allows secondary users (SU) to operate in the presence of the primary users (PU) and the OPNET simulation and modelling software has been used to model the performance of the scheme. An analysis of the results shows that the proposed scheme protects the primary users from harmful interference from the secondary users. In comparison with the 802.11 MAC protocol, the scheme improves spectrum utilization by about 27% while limiting the interference imposed on the primary receiver.
A Water-Saving Technique Using Embedded System  [PDF]
Ibrahim Mohammed Bader, Adel Hammad Abusitta
Applied Mathematics (AM) , 2013, DOI: 10.4236/am.2013.41021
Abstract:

A method for water-saving is presented in this paper. The proposed method is based on an electro mechanical approach and embedded system that is described mathematically. It describes a solution for water-saving in buildings by giving the ability to ensure that treasurer of water will never be empty before the maximum time T that the owner gives to the treasurer when it is filled with water. The rate of water pumped is altered based on water consumed at tr. Where tr is a random number generated by system. Simulation results in the last section shows that the method can save the water with different maximum time decided by the owner.

Aqueous-Phase Sorption Behaviors of Cs+, Co2+, Sr2+ and Cd2+ions on some Composite Ion Exchangers  [PDF]
Ibrahim Mohammed El-Naggar, Gehan Mohammed Ibrahim, Eman Ahmed El-Kady
Advances in Chemical Engineering and Science (ACES) , 2012, DOI: 10.4236/aces.2012.21021
Abstract: A two new hybrid “organic-inorganic” composite ion exchangers (SAM and FAM), was synthesized by the combination of inorganic ion exchanger tin (IV) silicate and tin (IV) antimonate respectively with organic polymer polyacrylamide (PAm). The sorption isotherms for Cs+, Co2+, Sr2+ and Cd2+ ions on composite ion exchanger were investigated in the range (0.0005 - 0.01M) at different reaction temperature (30℃, 45℃ and 60℃ ± 1℃). The sorption data were subjected to different sorption isotherms and the results verified that Langmuir isotherm is the best model to be applied, and the monolayer sorption capacity were calculated and was found to increase as the reaction temperature increases.
Advances in Genomic DNA Methylation Analysis
Mohammed A. Ibrahim
Biotechnology , 2010,
Abstract: Genomic DNA methylation is one of three epigenomic mechanisms controlling DNA expression. It is involved in various aspects of development and other biological phenomena of eukaryotic organisms. Several experimental approaches have been worked out to analyze DNA methylation. The main methodologies may be broadly classified into two categories, Polymerase Chain Reaction (PCR) based and non-PCR based methylation methods. PCR techniques are more powerful and reliable in analysis of genomic DNA methylation profiles. Three main processes are required in the PCR based analysis, detection of methylated cytosine and this is be done by methylation-sensitive enzymes or sodium bisulphite treatment, then followed by PCR amplification and sequencing. The present methods have their drawbacks, advantages and potential applications. Currently DNA methylation profiles of genomes are analyzed by sophisticated integrated technologies. The aim of present study is to review the early and up to date methods which have been invented for analysis of genomic DNA methylation.
Radiation Effects on Mass Transfer Flow through a Highly Porous Medium with Heat Generation and Chemical Reaction
S. Mohammed Ibrahim
ISRN Computational Mathematics , 2013, DOI: 10.1155/2013/765408
Abstract:
Effects of Mass Transfer, Radiation, Joule Heating, and Viscous Dissipation on Steady MHD Marangoni Convection Flow over a Flat Surface with Suction and Injection
S. Mohammed Ibrahim
International Journal of Engineering Mathematics , 2013, DOI: 10.1155/2013/903818
Abstract: The combined effects of radiation and mass transfer on a steady MHD two-dimensional Marangoni convection flow over a flat surface in presence of Joule heating and viscous dissipation under influence of suction and injection is studied numerically. The general governing partial differential equations are transformed into a set of nonlinear ordinary differential equations by using unique similarity transformation. Numerical solutions of the similarity equations are obtained using the Runge-Kutta method along with shooting technique. The effects of governing parameters on velocity, temperature, and concentration as well as interface velocity, the surface temperature gradient, and the surface concentration gradient were presented in graphical and tabular forms. Comparisons with previously published work are performed and the results are found to be in excellent agreement. 1. Introduction In recent years, many researchers have investigated the Marangoni convection and applied such convection to their problems. This is mainly because it is important in crystal growth melts and greatly influences other industrial processes. Nishino and Kawamura [1] stated that Marangoni convection negatively affects the quality of silicon crystals for semiconductors and the convection also occurs in heat pipe for heat radiation devices of personal computers. The surface tension gradient variations along the interface may induce the Marangoni convection. In particular, the surface tension gradients that are responsible for Marangoni convection can be due to gradients of temperature (thermal convection) and/or concentration (solutal convection). A lot of analyses in Marangoni convection have been discovered in various geometries and conditions. Some of experimental works linked to Marangoni convection were discussed in several papers by Arafune and Hirata [2], Arafune et al. [3], Galazka and Wilke [4], Neumann et al. [5], Arendt and Eggers [6], Xu et al. [7], and Christopher and Wang [8]. On the other hand, the study of Magnetohydrodynamics (MHD) is important in the heat and mass transport process. The study of heat transfer is integral part of natural convection flow and belongs to the class of problems in boundary layer theory. The quality of heat transferred is highly dependent upon the fluid motion within the boundary layer. A large number of physical phenomena involve natural convection that was studied by Jaluria [9], which are enhanced and driven by internal heat generation. In such flows the buoyancy force is incremented due to heat generation resulting in modification
Effects of Chemical Reaction on Dissipative Radiative MHD Flow through a Porous Medium over a Nonisothermal Stretching Sheet
S. Mohammed Ibrahim
Journal of Industrial Mathematics , 2014, DOI: 10.1155/2014/243148
Abstract: The steady two-dimensional radiative MHD boundary layer flow of an incompressible, viscous, electrically conducting fluid caused by a nonisothermal linearly stretching sheet placed at the bottom of fluid saturated porous medium in the presence of viscous dissipation and chemical reaction is studied. The governing system of partial differential equations is converted to ordinary differential equations by using the similarity transformations, which are then solved by shooting method. The dimensionless velocity, temperature, and concentration are computed for different thermophysical parameters, namely, the magnetic parameter, permeability parameter, radiation parameter, wall temperature parameter, Prandtl number, Eckert number, Schmidt number, and chemical reaction. 1. Introduction The fluid flows with chemical reaction have attracted the attention of engineers and scientists in the recent times. Such flows have key importance in many processes including drying evaporation at the surface of a water body, energy transfer in a wet cooling tower, flow in a desert cooler, generating electric power, food processing, groves of fruit trees, and crops damage because of freezing. There is always a molecular diffusion of species in the presence of chemical reaction within or at the boundary during several practical diffusive operations. There are two types of reactions, namely, homogeneous and heterogeneous. A homogeneous reaction takes place uniformly in the entire given phase whereas a heterogeneous reaction exists in a restricted region or within the boundary of a phase. The smog formation is an important example representing a first-order homogeneous chemical reaction. Several researchers in view of such facts are engaged in the discussion of flows with chemical reactions. For-instance Seddeek and Almushigeh [1] investigated the effects of radiation and variable viscosity on MHD free convective flow and mass transfer over a stretching sheet with chemical reaction. Kandasamy et al. [2] presented group analysis for Soret and Dufour effects on free convective heat and mass transfer with thermophoresis and chemical reaction over a porous stretching surface in the presence of heat source/sink. Pal and Talukdar [3] presented the combined effects of Joule heating and chemical reaction on unsteady magnetohydrodynamic mixed convection with viscous dissipation over a vertical plate in the presence of porous media and thermal radiation. Joneidi et al. [4] presented analytical treatment of MHD free convection flow over a stretching sheet with chemical reaction. Anjalidevi
Radiation Effects on Mass Transfer Flow through a Highly Porous Medium with Heat Generation and Chemical Reaction
S. Mohammed Ibrahim
ISRN Computational Mathematics , 2013, DOI: 10.1155/2013/765408
Abstract: The present paper is concerned to analyze the influence of the unsteady free convection flow of a viscous incompressible fluid through a porous medium with high porosity bounded by a vertical infinite moving plate in the presence of thermal radiation, heat generation, and chemical reaction. The fluid is considered to be gray, absorbing, and emitting but nonscattering medium, and Rosseland approximation is considered to describe the radiative heat flux in the energy equation. The dimensionless governing equations for this investigation are solved analytically using perturbation technique. The effects of various governing parameters on the velocity, temperature, concentration, skin-friction coefficient, Nusselt number and Sherwood number are shown in figures and tables and analyzed in detail. 1. Introduction Transport of momentum and energy in fluid-saturated porous media with low porosities are commonly described by Darcy’s model for conservation of momentum and by an energy equation based on the velocity field found from this model by Kaviany [1]. In contrast to rocks, soil, sand, and other media that do fall in this category, certain porous materials, such as foam metals and fibrous media, usually have high porosity. Vajravelu [2] examined the steady flow of heat transfer in a porous medium with high porosity. Raptis [3] studied mathematically the case of time varying two-dimensional natural convection heat transfer of an incompressible electrically conducting viscous fluid through a high porous medium bounded by an infinite vertical porous plate. Hong et al. [4], Chen and Lin [5], and Jaiswal and Soundalgekar [6] studied the natural convection in a porous medium with high porosity. Hiremath and Patil [7] studied the effect of free convection currents on the oscillatory flow of the polar fluid through a porous medium, which is bounded by the vertical plane surface with constant temperature. Many processes in engineering areas occur in high temperature and consequently the radiation plays a significant role. Chandrasekhara and Nagaraju [8] examined the composite heat transfer in a variable porosity medium bounded by an infinite vertical flat plate in the presence of radiation. Yih [9] studied the radiation effects on natural convection over a cylinder embedded in porous media. Mohammadein and El-Amin [10] considered the thermal radiation effects on power law fluids over a horizontal plate embedded in a porous medium. Raptis [11] studied the heat transfer in a porous medium with high porosity in the presence of radiation. Raptis and Perdikis [12] studied
Laparoscopic Rectopexy; Is It Useful for Persistent Rectal Prolapse in Children?  [PDF]
Medhat M. Ibrahim, Mohammed Abd El Razik, Ahmed M. Abdelkader
Surgical Science (SS) , 2014, DOI: 10.4236/ss.2014.53023
Abstract:

Introduction: Rectal prolapse is a relatively common, usually self-limiting illness in children. Peak incidence is between 1 and 3 years. The intervention is required for the persistent rectal prolapse (PRP). Only scanty experience is available with laparoscopic rectopexy in children. There is no available work using both mesh and suture laparoscopic rectopexy in literature. This work is unique that it presents our clinical experience with both mesh and suture laparoscopic rectopexy in children. This is a prospective clinical study for the outcome of laparoscopic rectopexy (LRP) by both mesh and suture technique in children with persistent rectal prolapse (PRP). Materials and Methods: Fourteen cases of PRP were managed with LRP from February 2008 to August 2012. Results: Of the 14 children, 10 (71.42%) were males and 4 (28.57%) were females. Male to female ratio was 2:1. The mean age of presentation was 5 years (range 3 - 8 years). The presenting complaints were mass descending per rectum along with bleeding per rectum lasting from 1 to 3 years. All had rectal prolapse of 5 - 7 cm in length. 12 out of 14 children had recurrence even after sclerotherapy before referral to laparoscopic rectpexy. The mean duration of surgery was 30 minutes (range 20 - 60 minutes). No intraoperative complications were reported;

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