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Open Journal of Nephrology 2024年第2期14卷 275-293页

作者： Rihab Dkhissi Nada el Kadiri Tarik Bouattar Loubna Benamar Naima Ouzeddoun Department of Nephrology-Dialysis-Renal Transplantation IbnSina Hospital Mohammed V University Rabat Morocco

Introduction: Autosomal dominant polycystic kidney disease (ADPKD) is a common, multisystemic, and progressive hereditary disease. It accounts for 6 to 8% of incident cases of end-stage chronic renal disease (ESRD) in developed countries. The aim of this study is to describe the predictive factors for the development of end-stage chronic kidney disease (CKD) in the course of this disease. Material and Methods: This is a retrospective, descriptive, and analytical study including 300 cases of ADPKD collected at the Nephrology Department of Ibn-Sina Hospital in Rabat over a period of 30 years (1993 to 2023). Included in the study are all patients with ADPKD meeting the ultrasound diagnostic criteria. The analysis focused on demographic, clinical, paraclinical, evolutionary data, as well as prognostic factors associated with renal function deterioration. Results: The mean age of patients at diagnosis is 51.53 +/− 17 years [16 - 93] with a male predominance. The median serum creatinine at diagnosis is 15.5 mg/l [10 - 34]. 21% of patients had ESRD (eGFR 300 mg/24h (21%). The most common cystic complication is hemorrhage (12.3%). 21.3% of patients had hepatorenal polycystic disease. In adjusted analysis, the predictive risk factors for the occurrence of ESRD were smoking (p = 0.019), anemia (p Conclusion: ADPKD can progress insidiously to ESRD. Identification and early treatment of predictive factors for poor renal prognosis could contribute to a better outcome for this disease.

关键词： ADPKD ESRD Factors of Poor Renal Prognosis Renal and Extra-Renal Manifestations

An Efficient Hybrid Model for Arabic Text Recognition

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Computers, Materials & Continua 2023年第2期74卷 2871-2888页

作者： Hicham Lamtougui Hicham el Moubtahij hassan Fouadi Khalid Satori LIIAN Laboratory Faculty of Sciences Dhar-MahrazFez30000Morocco Modeling Systems and Technologies of Information TeamUniversity of Ibn ZohrAgadir

In recent years,Deep Learning models have become indispensable in several fields such as computer vision,automatic object recognition,and automatic natural language *** implementation of a robust and efficient handwritten text recognition system remains a challenge for the research community in this field,especially for the Arabic language,which,compared to other languages,has a dearth of published *** this work,we presented an efficient and new system for offline Arabic handwritten text *** new approach is based on the combination of a Convolutional Neural Network(CNN)and a Bidirectional Long-Term Memory(BLSTM)followed by a Connectionist Temporal Classification layer(CTC).Moreover,during the training phase of the model,we introduce an algorithm of data augmentation to increase the quality of *** proposed approach can recognize Arabic handwritten texts without the need to segment the characters,thus overcoming several problems related to this *** train and test(evaluate)our approach,we used two Arabic handwritten text recognition databases,which are IFN/ENIT and *** Experimental results show that our new approach,compared to other methods in the literature,gives better results.

关键词： Deep learning arabic handwritten text recognition convolutional neural network(CNN) bidirectional long-term memory(BLSTM) connectionist temporal classification(CTC)

On the gradient tracking problem for a bilinear reaction–diffusion equation excited by distributed bounded controls

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Journal of Control and Decision 2023年第3期10卷 365-373页

作者： el hassan Zerrik Abderrahman Ait Aadi Mohamed Ouhafsaa MACS Laboratory Faculty of SciencesMoulay Ismail UniversityMeknesMorocco Department of Sciences Ecole Normale SupérieureMoulay Ismail UniversityMeknesMorocco

This paper addresses a gradient tracking problem of a bilinear reaction–diffusion equation evolvingin a spatial domainΩ ⊂ Rn, n ≤ 3. Such an equation is excited with distributed and boundedcontrols. The problem is formulated by the minimisation of a functional constituted of the deviationbetween the desired gradient and the current one all over a time interval and the energyterm. Then we prove the existence of an optimal control that we characterise by an optimalitysystem. Moreover, we discuss two sets of particular controls: the set of time dependent controlsand the space dependent ones. A computational approach and illustrative simulations are alsogiven.

关键词： Infinite dimensional systems bilinear systems reaction–diffusion equation controllability optimal control

Numerical Modeling and Technico-Economic Analysis of a Hybrid Energy Production System for Self-Consumption: Case of Rural Area in the Comoros

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Journal of Power and Energy Engineering 2024年第5期12卷 24-59页

作者： Fahad Maoulida Mohamed Aboudou Kassim Rabah Djedjig Ahmed Ihlal Mohammed el Ganaoui LERMAB Laboratory of Studies and Research on Wood Material IUT of Longwy University of Lorraine Cosnes-et-Romain Longwy France LEMA Energy and Applied Mechanics Laboratory Faculty of Sciences and Techniques University of Comoros Moroni Comoros IREMIS Institute University of Mayotte Mayotte France LMER Laboratory of Materials and Renewable Faculty of Sciences University Ibn Zohr BP Agadir Morocco

This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW photovoltaic solar panels, a converter, and storage batteries as the proposed sources. The main objective of this study is to conduct a detailed analysis and optimization of a hybrid diesel and renewable energy system to meet the electricity demand of a remote area village of 800 to 1500 inhabitants located in the north of Ngazidja Island in Comoros. The study uses the Hybrid Optimization Model for electric Renewable (HOMER) Pro to conduct simulations and optimize the analysis using meteorological data from Comoros. The results show that hybrid combination is more profitable in terms of margin on economic cost with a less expensive investment. With a diesel cost of $1/L, an average wind speed of 5.09 m/s and a solar irradiation value of 6.14 kWh/m2/day, the system works well with a proportion of renewable energy production of 99.44% with an emission quantity of 1311.407 kg/year. 99.2% of the production comes from renewable sources with an estimated energy surplus of 2,125,344 kWh/year with the cost of electricity (COE) estimated at $0.18/kWh, presenting a cost-effective alternative compared to current market rates. These results present better optimization of the used hybrid energy system, satisfying energy demand and reducing the environmental impact.

关键词： Hybrid System Rural Area electrification Comoros Techno-Economic Analysis PV-Wind-Diesel-Battery Meteorological Data HOMER Energy Pro

Particle Swarm Optimization-Based Hyperparameters Tuning of Machine Learning Models for Big COVID-19 Data Analysis

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Journal of Computer and Communications 2024年第3期12卷 160-183页

作者： Hend S. Salem Mohamed A. Mead Ghada S. el-Taweel Department of Computer Sciences Suez Canal University Ismailia Egypt

Analyzing big data, especially medical data, helps to provide good health care to patients and face the risks of death. The COVID-19 pandemic has had a significant impact on public health worldwide, emphasizing the need for effective risk prediction models. Machine learning (ML) techniques have shown promise in analyzing complex data patterns and predicting disease outcomes. The accuracy of these techniques is greatly affected by changing their parameters. Hyperparameter optimization plays a crucial role in improving model performance. In this work, the Particle Swarm Optimization (PSO) algorithm was used to effectively search the hyperparameter space and improve the predictive power of the machine learning models by identifying the optimal hyperparameters that can provide the highest accuracy. A dataset with a variety of clinical and epidemiological characteristics linked to COVID-19 cases was used in this study. Various machine learning models, including Random Forests, Decision Trees, Support Vector Machines, and Neural Networks, were utilized to capture the complex relationships present in the data. To evaluate the predictive performance of the models, the accuracy metric was employed. The experimental findings showed that the suggested method of estimating COVID-19 risk is effective. When compared to baseline models, the optimized machine learning models performed better and produced better results.

关键词： Big COVID-19 Data Machine Learning Hyperparameter Optimization Particle Swarm Optimization Computational Intelligence

Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763页

作者： Laura Khudaysh Inas A.Ahmed Syeda Rabia Ejaz Sajjad Ahmad Khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.el-Bahy Department of Physics Faculty of ScienceJazan University Department of Chemistry Faculty of ScienceKing Khalid University Department of Physics The Government Sadiq College Women University Institute of Physics Khwaja Fareed University of Engineering and Information Technology Department of Chemistry College of ScienceTaif University Centre of Excellence in Solid State Physics University of the Punjab Department of Physics Government College Department of Chemistry Faculty of ScienceAl-Azhar University

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co0.6Sr0.4CexFe2-xO4. Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

Graphite Carbone Structure

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Crystal Structure Theory and Applications 2024年第1期12卷 1-10页

作者： Lahbib Abbas Lahcen Bih Khalid Yamni Abderrahim elyahyaouy Abdelmalik el Attaoui Zahra Ramzi Materials Membranes and Nanotechnology Laboratory Faculty of Science and Technology Moulay Ismail University Errachidia Morocco Engineering Sciences and Professions Laboratory National School of Arts and Crafts Moulay Ismail University Meknes Morocco Materials Membranes and Nanotechnology Laboratory Chemistry Department Faculty of Sciences Moulay Ismail Univer-sity Meknes Morocco Physics Department Faculty of Sciences Ibn Tofail University Kenitra Morocco Laboratory of Molecular Chemistry Materials and Environment (LCM2E) Multidisciplinary Faculty of Nador Mohamed 1st University Nador Morocco Laboratory of SCiMATOP Chemistry Department Faculty of Sciences Semlalia Cadi Ayyad University Marrakech Morocco

Carbon graphite is a crystalline form of carbon consisting of layers of hexagonal carbon atoms arranged in a two-dimensional “graphene” structure. Graphene layers are stacked on top of each other, forming a three-dimensional structure with a high degree of anisotropy. The carbon atoms within each layer are linked together by strong covalent bonds, creating a strong, stable lattice structure. However, the layers themselves are held together by weak van der Waals forces, enabling them to slide easily over each other. The properties of carbon graphite are highly dependent on the orientation and alignment of the graphene layers. When the layers are aligned parallel to each other, the material exhibits high strength and stiffness along the alignment direction, but is weaker and more flexible in other directions. Carbon graphite is used in a variety of applications where high strength, rigidity and electrical conductivity are required. Some common applications include electrical contacts, electric motor brushes, and as a structural material in aerospace and defense applications. The aim of our work is to describe the structure of graphite, its physical and chemical properties and its applications.

关键词： Graphite Graphene Hexagonal Structure Hardness Rigidity electrical Con-ductivity

Determination of Latent Heats of Vaporization and Fusion

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Advances in Chemical Engineering and Science 2024年第3期14卷 113-124页

作者： Lahbib Abbas Lahcen Bih Khalid Yamni Abderrahim elyahyaouy Abdelmalik el Attaoui Zahra Ramzi Chemistry Department Faculty of Science and Technology Moulay Ismail University Meknes Er-Rachidia Morocco Engineering Sciences and Professions Laboratory National School of Arts and Crafts Moulay Ismail University Meknes Meknes Morocco Materials Membranes and Nanotechnology Chemistry Department Faculty of Sciences Moulay Ismail University Meknes Zitoune Mekns Morocco Physics Department Faculty of Sciences Ibn Tofail University Kenitra Morocco Laboratory of Molecular Chemistry Materials and Environment (LCM2E) Multidisciplinary Faculty of Nador Mohamed 1st University Oujda Nador Morocco Laboratory of SCiMATOP Chemistry Department Faculty of Sciences Semlalia Cadi Ayyad University Marrakech Morocco

Water is the most abundant liquid on the surface of the earth. It is a liquid whose properties are quite surprising, both as a pure liquid and as a solvent. Water is a very cohesive liquid: its melting and vaporization temperatures are very high for a liquid that is neither ionic nor metallic, and whose molar mass is low. Thus, water remains liquid at atmospheric pressure up to 100C while similar molecules such as H2S, H2Se, H2Te for example would give a vaporization temperature close to 80C. This cohesion is in fact ensured by hydrogen bonds between water molecules. This type of bonds between neighboring molecules, hydrogen bonds, is quite often found in chemistry [1] [2]. Any change in the state of aggregation of a substance occurs with the absorption or release of a certain amount of latent heat of transformation. Latent heat of fusion, vaporization or sublimation is the ratio of the energy supplied as heat to the mass of the substance that is melted, vaporized or sublimated. As a result of the reversibility of the processes, the fusion heat is equal to the heat released in the reverse process: crystallization and solidification heat. And likewise the heat of vaporization is equal to the heat of condensation. This equality of heat is often used to determine experimentally either of these quantities. There are two main measurement methods: 1) Direct measurement using the calorimeter, 2) Indirect measure based on the use of the VantHoff relationship. The objective of this work is to measure the latent heat of water vaporization and verify the compatibility of the experimental values with the values given by the tables using the indirect method.

关键词： Latent Heat of Vaporization Latent Heat of Fusion Calorimetry Relationship of Vant’Hoff

A Typical Case of Classic Potter’s Syndrome: A Case Report

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Open Journal of Pediatrics 2024年第3期14卷 482-487页

作者： Mohamed el Kerim Mahy Mohammed Ech-Chebab Anass Ayyad Sahar Messaoudi Rim Amrani Pediatrics/Residency Mohammed VI University Hospital Oujda Morocco Department of Neonatology and Neonatalintensive Care Unit Mohammed VI University Hospital Medical School University Mohammed 1st Oujda Morocco The Maternal-Child & Mental Health Research Laboratory Oujda Morocco

Potter syndrome is a rare congenital malformation that primarily affects male fetuses;it is characterized by pulmonary hypoplasia, skeletal malformation, and kidney abnormalities. The pressure of the uterine wall due to oligohydramnios leads to an unusual facial appearance, abnormal limbs in abnormal positions, or contractures. The fetus generally dies soon after birth due to respiratory insufficiency. The baby was a live preterm male, born to a 30-year-old multigravida, out of a non-consanguineous marriage via cesarean section. There was no liquor at the time of delivery. The baby did not cry immediately after birth and required resuscitation, followed by mechanical ventilation. Multiple congenital anomalies suggestive of Potter’s syndrome were noted including facial features, flattened nose, low protruding ear, retrognathism, and epicanthal folds with unilateral atresia of the choana. Chest X-ray showed small volume lung fields suggestive of pulmonary hypoplasia, and we had on ultrasonography bilateral polycystic kidney disease on ultrasonography. At 42 hours of life, the baby developed tachypnea and severe chest retractions and died due to respiratory insufficiency. Our case highlights the importance of regular prenatal checks and examinations in each pregnancy, which helps to collect suspected cases and improve knowledge of this syndrome for better management.

关键词： Potter Syndrome Pulmonary Hypoplasia Potter’s Facies Polycystic Kidney Oligohydramnios

Systematic Method for Constructing Lewis Representations

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Open Journal of Inorganic Chemistry 2024年第1期14卷 1-18页

作者： Lahbib Abbas Lahcen Bih Khalid Yamni Abderrahim elyahyaouy Abdelmalik el Attaoui Zahra Ramzi Materials Membranes and Nanotechnology Faculty of Science and Technology Moulay Ismail University Meknes Er-Rachidia Morocco Engineering Sciences and Professions Laboratory National School of Arts and Crafts Moulay Ismail University Meknes Meknes Morocco Materials Membranes and Nanotechnology Chemistry Department Faculty of Sciences Moulay Ismail University Meknes Meknes Morocco Physics Department Faculty of Sciences Ibn Tofail University Kenitra Morocco Laboratory of Molecular Chemistry Materials and Environment (LCM2E) Multidisciplinary Faculty of Nador Mohamed 1st University Oujda Nador Morocco Laboratory of SCiMATOP Chemistry Department Faculty of Sciences Semlalia Cadi Ayyad University Marrakech Morocco

The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods.

关键词： Systematic Method Lewis Representation Chemical Bond Formal Charge Oxidation Number