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World Journal of Gastroenterology 2014年第25期20卷 8292-8297页

作者： Raja GR Edula Kamran Qureshi hicham Khallafi Department of Medicine Division of Gastroenterology and HepatologyRutgers New Jersey Medical SchoolNewarkNJ 07103United States Department of Hepatology Florida Hospital Transplant CenterOrlando FL 32804United States

Bleeding from gastro-esophageal varices can often present as the first decompensating event in patients with cirrhosis. This can be a potentially life threatening event associated with a 15%-20% early mortality. We present a rare case of new onset ascites due to intra-abdominal hemorrhage from ruptured mesenteric varices; in a 37 years old male with newly diagnosed nonalcoholic steatohepatitis induced cirrhosis as the first decompensating event. The patient was successfully resuscitated with emergent evacuation of ascites for diagnosis, identification and control of bleeding mesenteric varices and eventually orthotopic liver transplantation with successful outcome. Various clinical presentations, available treatment options and outcomes of ectopic variceal bleeding are discussed in this report.

关键词： Cirrhosis Nonalcoholic steatohepatitis Ectopic var

Condensation Heat Transfer in Horizontal Non-Circular Microchannels

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Energy and Power Engineering 2013年第9期5卷 577-586页

作者： hicham El Mghari Mohamed Asbik Hasna Louahlia-Gualous LP2MS URAC08Universite Moulay IsmailFaculte des SciencesMeknesMaroc LUSAC Universite de Caen Basse NormandieSaint LoFrance

This investigation contributes to a better understanding of condensation heat transfer in horizontal non-circular microchannels. For this purpose, the conservation equations of mass, momentum and energy have been numerically solved in both phases (liquid and vapor), and all the more, so the film thickness analytical expression has been established. Numerical results relative to variations of the meniscus curvature radius, the condensate film thickness, the condensation length and heat transfer coefficients, are analyzed in terms of the influencing physical and geometrical quantities. The effect of the microchannel shapes on the average Nusselt number is highlighted by studying condensation of steam insquare, rectangular and equilateral triangular microchannels with the same hydraulic diameter of 250 μm.

关键词： Condensation Microchannel Numerical Simulation Capillary Regime Heat Transfer

Forest Cover Monitoring and Change Detection in Nfifikh Forest (Morocco)

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Journal of Geographic Information System 2018年第2期10卷 219-233页

作者： Loubna Khalile Hassan Rhinane Abdelhadi Kaoukaya hicham Lahlaoi Faculté des Sciences Aï n Chock Université Hassan II-Casablanca Casablanca Morocco

Peri-urban forests are subject to different dynamics due to several factors. Nfifikh forest is a man-made space, located in suburban of Mohammedia City, belonging to Casablanca, Settat Region, and geographically between Casablanca, the economic and business Capital of Morocco and Rabat, the national political capital. Over the past three decades, it has experienced several significant degradations. The aim of this study is to evaluate and quantify the deforestation within the study area using a forest cover change detection of various vegetation indices and subpixel classification to pick out high density plots with Landsat images TM, ETM+ and OLI. Remote sensing is used to highlight the changes caused through Space-Time. This monitoring might help managers to generate forest management plans and to moderate the speed of deforestation and degradation. The results show a significant change in vegetation cover detected between 1987 and 2015. The Density increased in 2001 while it decreased considerably in 2015.

关键词： Subpixel Vegetation Indices Change Detection Monitoring Nfifikh Forest

Very Compact Bandstop Filters Based on Miniaturized Complementary Metamaterial Resonators

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Wireless Engineering and Technology 2013年第2期4卷 101-104页

作者： hicham Lalj Hafid Griguer M’hamed Drissi European University of Bretagne National Institute of Applied Science of Rennes Institute of Electronic and Telecommunication of Rennes Rennes France European University of Bretagne National Institute of Applied Science of Rennes Institute of Electronic and Telecommunication of Rennes Rennes France Moroccan School of Engineering Science of Rabat Rabat Morocco

In this paper, a design of very compact microstrip bandstop filters based on complementary split ring resonators (CSRRs) is proposed. Two techniques of metamaterial miniaturization are used to optimize the physical and electrical size of the CSRR. The bandstop filter is produced by an array of miniaturized loaded CSRRs etched on the center line of a microstrip. The size of the proposed filter, is as small as 0.58 cm2, and its electrical length is very small with only 0.08 λ0), compared to a conventional bandstop filter, a miniaturization of a factor 5 while the bandstop performance is maintained. A very good agreement obtained between the measurement and the simulation results.

关键词： Metamaterials Bandstop Filter Complementary Split Ring Resonators (CSRRs)

Embedded Dual band Cylindrical Dielectric Resonator Antenna

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International Journal of Communications, Network and System Sciences 2011年第10期4卷 656-661页

作者： Ahmed Benomar Noureddine Boukli Hacene hicham Megnafi Patrick Vaudon 不详

A compact dual band antenna made of high dielectric constant substrate is studied. Embedding a higher dielectric cylindrical inside the substrate host cylindrical enhances the dual band behaviour. The first part displays the characteristics of single CRDA as return loss, bandwidth and radiation pattern, then, the second part describes the aim of using an antenna, composed by the arrangement of two cylindrical resonators in which the smallest is inserted in the largest, to lead dual-frequency behaviour, and achieve a dual-band antenna. The proposed antennas are investigated using Finite Element Method (FEM), the impedance matching dual band definition and covers the Ultra High Frequency band (UHF).

关键词： Dual Band Antenna Bandwidth Return Loss UHF DCS

Processes for the Clarification of the Crude Oil of Baobab Seeds Extracted by Pressing on Activated Carbon Elaborated from the Capsules of the Fruit (Adansonia digitata L.)

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Advances in Chemical Engineering and Science 2023年第2期13卷 105-118页

作者： Edouard Mbarick Ndiaye Alioune Sow Kalidou Ba Mouhamed Ndoye Yousra El Idrissi Seyni Ndiaye Hamza El Moudden Papa Guedel Faye hicham Harhar Nicolas Ayessou Mohamed Tabyaoui Mady Cisse Laboratory of Water Energy Environment and Industrial Processes (LE3PI) ESP-UCAD ESP-UCAD Cheikh Anta Diop University Dakar Senegal Laboratory of Materials Nanotechnology and Environment Faculty of Sciences-Rabat Mohammed V University of Rabat Rabat Morocco Laboratory of Biological Agronomic Food Sciences and Modeling of Complex Systems (LABAAM) UFR of Agronomic Scienc-es Aquaculture and Food Technologies (S2ATA) Gaston Berger University of Saint-Louis Saint-Louis Senegal Higher School of Technology of El Kelaa of The Sraghna Cadi Ayyad University Marrakech Morocco

The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39a for the initial crude oil to 128.53d for the oil treated with 3% activated carbon versus 187.59a for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99b). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67b against 79.04a for the oil filtered with 3% activated carbon, 86.33a fo

关键词： Activated Carbon Baobab Oil Clarification Filtration Process

Gastric leaks post sleeve gastrectomy:Review of its prevention and management

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World Journal of Gastroenterology 2014年第38期20卷 13904-13910页

作者： Antoine Abou Rached Melkart Basile hicham El Masri Department of Internal Medicine Gastroenterology DivisionLebanese University Department of General Surgery Lebanese University

Gastric sleeve gastrectomy has become a frequent bariatric procedure. Its apparent simplicity hides a number of serious,sometimes fatal,complications. This is more important in the absence of an internationally adopted algorithm for the management of the leaks complicating this operation. The debates exist even regarding the definition of a leak,with several classification systems that can be used to predict the cause of the leak,and also to determine the treatment plan. Causes of leak are classified as mechanical,technical and ischemic causes. After defining the possible causes,authors went into suggesting a number of preventive measures to decrease the leak rate,including gentle handling of tissues,staple line reinforcement,larger bougie size and routine use of methylene blue test per operatively. In our review,we noticed that the most important clinical sign or symptom in patients with gastric leaks are fever and tachycardia,which mandate the use of an abdominal computed tomography,associated with an upper gastrointrstinal series and/or gastroscopy if no leak was detected. After diagnosis,the management of leak depends mainly on the clinical condition of the patient and the onset time of leak. It varies between prompt surgical intervention in unstable patients and conservative management in stable ones in whom leaks present lately. The management options include also endoscopic interventions with closure techniques or more commonly exclusion techniques with an endoprosthesis. The aim of this review was to highlight the causes and thus the prevention modalities and find a standardized algorithm to deal with gastric leaks post sleeve gastrectomy.

关键词： Gastrectomy Bariatric surgery Obesity Anas-tomotic

Analysis of the Silting Rate in the “Hachef” Dam Situated in Northern Morocco in the Context of Global Change

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Journal of Geographic Information System 2020年第2期12卷 112-124页

作者： Abderrahim El Boukhari Mohamed Chikhaoui hicham Mharzi-Alaoui Mustapha Naimi Center for Doctoral Studies IAV Hassan II Rabat Morocco Department of Natural Resources & Environment IAV Hassan II Rabat Morocco National Center for Climatic and Forest Risk Management Rabat Morocco

The Moroccan annual dam silting corresponds to a loss in storage capacity of the reservoirs of about 75 million m3 per year. Land use metamorphosis and the ongoing climate changes are likely to accelerate the process of soil degradation and erosion. In this delicate context, Morocco will have to provide appropriate responses in terms of adaptation and remediation strategies to the degradation of soil and water resources. The objectives of this paper are to characterize the Specific Degradation (SD) of the Tangier basin through the study of the silting of the watershed located upstream the Hachef dam and to analyze the silting rate of the Hachef dam according to the variability of precipitations and the dynamics of the vegetation convent. The adopted approach is based on the analysis of the bathymetric surveys of the Hachef Dam to characterize the SD and the analysis of the silting rate based on the characterization of the spatial and temporal variability of the two key factors of water erosion. The results of processing the bathymetric surveys over a 19-year analysis period (1995-2014) show an annual average total silting of about 11.46 Mm3 and a corresponding SD of about 36.7 t⋅ha−1⋅yr−1. This study shows the significant influence of the spatial and temporal variability of precipitation and vegetation cover on the silting dynamics of dams.

关键词： Dam Silting Spatial and Temporal Variability Hachef Dam Morocco

Opto-Structural Properties of Silicon Nitride Thin Films Deposited by ECR-PECVD

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World Journal of Condensed Matter Physics 2016年第1期6卷 7-16页

作者： hicham Charifi Abdelilah Slaoui Jean Paul Stoquert Hassan Chaib Abdelkrim Hannour Laboratory of Condensed Matter Physics and Nanomaterials for Renewable Energy University Ibn Zohr Agadir Morocco ICube CNRS-Université de Strasbourg Strasbourg France Research Group Materials and Energy Polydisciplinary Faculty Ibn Zohr University Ouarzazate Morocco

Amorphous hydrogenated silicon nitride thin films a-SiNx:H (abbreviated later by SiNx) were deposited by Electron Cyclotron Resonance plasma enhanced chemical vapor deposition method (ECR-PECVD). By changing ratio of gas flow (R = NH3/SiH4) in the reactor chamber different stoichiometric layers x = [N]/[Si] ([N] and [Si] atomic concentrations) are successfully deposited. Part of the obtained films has subsequently undergone rapid thermal annealing RTA (800°C/1 s) using halogen lamps. Optical and structural characterizations are then achieved by spectroscopic ellipsometry (SE), ion beam analysis and infrared absorption techniques. The SE measurements show that the tuning character of their refractive index n(λ) with stoichiometry x and their non-absorption properties in the range of 250 - 850 nm expect for Si-rich SiNx films in the ultraviolet UV range. The stoichiometry x and its depth profile are determined by Rutherford backscattering spectrometry (RBS) while the hydrogen profile (atomic concentration) is determined by Elastic Recoil Detection Analysis (ERDA). Vibrational characteristics of the Si-N, Si-H and N-H chemical bonds in the silicon nitride matrix are investigated by infrared absorption. An atomic hydrogen fraction ranging from 12% to 22% uniformly distributed as evaluated by ERDA is depending inversely on the stoichiometry x ranging from 0.34 to 1.46 as evaluated by RBS for the studied SiNx films. The hydrogen loss after RTA process and its out-diffusion depend strongly on the chemical structure of the films and less on the initial hydrogen concentration. A large hydrogen loss was noted for non-thermally stable Si-rich SiNx films. Rich nitrogen films are less sensitive to rapid thermal process.

关键词： ECR-PECVD Silicon Nitride

Potential Erosion Risk Calculation Using Remote Sensing and GIS in Oued El Maleh Watershed, Morocco

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Journal of Geographic Information System 2015年第2期7卷 128-139页

作者： hicham Lahlaoi Hassan Rhinane Atika Hilali Said Lahssini Loubna Khalile Geosciences Laboratory Faculty of Sciences Ain Chock Hassan II University Casablanca Morocco National School of Forestry Engineering Salé Morocco

Oued El Maleh watershed is considered the largest ocean basin of the Chaouia-Ouardigha region in Morocco. Severe flooding occurred in 1996, 2001 and 2002 in the watershed. Thus, significant economic and human damage has been caused. The floods of Mohammedia city, located in the outlet of the watershed, were due to the silting of the Oued El Maleh dam which has lost its ability to retain water. This work, therefore, aims to assess soil losses by water erosion in the Oued El Maleh watershed through modeling main factors involved in water erosion. The methodology used is based on the use of the universal soil loss equation (USLE). The model includes the following factors: soil erodibility, the inclination of slopes, the rainfall erosivity, vegetation cover and erosion control practices. The aggressiveness of rainfall was calculated for a number of stations bordering the study area and interpolated across the watershed using geostatistical model. Soil erodibility was extracted from soil map and soil survey. The effect of topography was approached by combining the degree of slope and slope length using a digital elevation model (ASTER) and ArcHydrology extension (ArcGIS). The vegetation cover was derived from Landsat image ETM through the supervised classification method. The index of erosion control practices was approached by field visits. All factors have been measured and integrated into a geographic information system which enabled us to spatialize the degree of sediment production at the watershed scale in a synthetic map. The annual soil loss is 8.21 t/ha/yr and the soil loss classification shows that surfaces affected by high erosion are equivalent to 10% of the watershed. Furthermore, this map is available to support land managers policy makers in the process of decision making related to soil conservation, infrastructure and citizens’ property protection.

关键词： Watershed Oued El Maleh Erosion USLE Geographic Information System