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3D crustal density modeling of Egypt using GOCE satellite gravity data and seismic integration

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Earthquake Science 2025年第2期38卷 110-125页

作者： Moataz sayed mohamed Sobh Salah Saleh Amal Othman ahmed Elmahmoudi National Research Institute of Astronomy and Geophysics (NRIAG) Helwan 11421 Cairo Egypt Leibniz Institute for Applied Geophysics Hannover 30655 Germany Geology Department Faculty of Science Mansoura University Mansoura 35516 Egypt

A 3D crustal model was constructed using a combination of cutting-edge techniques, which were integrated to provide a density model for Egypt and address the sporadic distribution of seismic data. These techniques include obtaining gravity data from the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE), creating seismic profiles, analyzing the receiver functions of seismic data, obtaining information from boreholes, and providing geological interpretations. GOCE satellite gravity data were processed to construct a preliminary model based on nonlinear inversions of the data. A regional crustal thickness model was developed using receiver functions, seismic refraction profiles, and geological insights. The inverted model was validated using borehole data and compared with seismic estimates. The model exhibited strong consistency and revealed a correlation between crustal thickness, geology, and tectonics of Egypt. It showed that the shallowest depths of the Moho are located in the north along the Mediterranean Sea and in the eastern part along the Red Sea, reflecting an oceanic plate with a thin, high-density crust. The deepest Moho depths are located in the southwestern part of Egypt, Red Sea coastal mountains, and Sinai Peninsula. The obtained 3D model of crustal thickness provided finely detailed Moho depth estimates that aligned closely with geology and tectonic characteristics of Egypt, contributing valuable insights into the subsurface structure and tectonic processes of region.

关键词： GOCE satellite gravity Moho depth crustal modeling gravity inversion

Role of Right Ventricular-Pulmonary Arterial Coupling Measured by Echocardiography in Predicting Right Ventricular Dysfunction after Cardiac Surgery

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World Journal of Cardiovascular Surgery 2025年第1期15卷 1-11页

作者： Ismail Nasr El-Sokkary Esam ahmed Khalil Mohammed Fawzy Eltaweel ahmed Alherazi Mohammed Samy Bahaa Abdelgawad Elkhonezy mohamed El sayed Moussa mohamed ahmed Mosaad Zaki Ibrahim Abdel Fattah Yassin mohamed Kamal Rehan Department of Cardiothoracic Surgery Faculty of Medicine Al-Azhar University Cairo Egypt Department of Cardiology Al-Azhar University Faculty of Medicine Cairo Egypt Department of Cardiothoracic Surgery Faculty of Medicine Menoufia University Shibin El Kom Egypt Department of Cardiothoracic Surgery Faculty of Medicine Alexandria University Alexandria Egypt Department of Internal Medicine Faculty of Medicine Beni Suef University Cairo Egypt

Background: The tricuspid annular plane systolic excursion (TAPSE) and pulmonary artery systolic pressure (PASP) is an indirect estimate of right ventricular-pulmonary arterial (RV-PA) coupling that has been shown to correlate with invasive measures. We aimed to assess the ability of the tricuspid annular plane systolic excursion/pulmonary systolic pressure ratio (TAPSE/PASP) as a measure for RV-PA coupling to predict the development of RV dysfunction after cardiac surgery. Methods: This prospective study was conducted on 100 patients with ischemic heart disease and undergoing cardiac surgery (coronary artery bypass graft (CABG)) with normal preoperative right ventricular function, classified according to RV function outcomes into 2 groups: Normal RV group (65 patients) and RV dysfunction group (35 patients). All cases underwent per and postoperative transthoracic echocardiography. Results: By using receiver operating characteristic curve analysis, pre-operative TAPSE/PASP ratio could significantly predict the RV dysfunction (P 0.58, with AUC of 94%, 88.6% sensitivity, and 89.2% specificity. Post-operative TAPSE/PASP Ratio could significantly predict the RV dysfunction (P 0.39, with AUC of 84%, 100% sensitivity, and 76.9% specificity. Pre-operative TAPSE/PASP ratio could significantly predict mortality (P Conclusion: The TAPSE/PASP ratio is an excellent tool for CABG patients for its ability to detect and predict the development of RV dysfunction after cardiac surgery, along with the prediction of mortality in post-operative CABG patients.

关键词： Right Ventricular Pulmonary Arterial Coupling Echocardiography Cardiac Surgery

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid ahmed Tadjer Abdelhakim Idir Kong Fah Tee mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Effects of rare-earth Pr3+-Dy3+ doping on structural,magnetic,optical and dielectric properties of Zn2Y hexaferrite

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Journal of Rare Earths 2025年第2期43卷 329-336页

作者： Ibrahim Mohammed mohamed E.El sayed Ali Shawabkeh Mohammad N.Murshed Ibtehaj F.Alshdoukhi Zeinhom M.El-Bahy J.Mohammed A.K.Srivastava Department of Physics Lovely Professional University Department of Science Technology Waziri Umaru Federal Polytechnic Birnin Kebbi Physics Department Faculty of Science and ArtsKing Khalid University College of Engineering and Technology American University of the Middle East Department of Basic Sciences College of Science and Health ProfessionsKing Saud Bin Abdulaziz University for Health ScienceKing Abdullah International Medical Research Center Department of Chemistry Faculty of ScienceAl-Azhar University Department of Physics Faculty of ScienceFederal University Dutse

This study was conducted to investigate the properties of Pr3+-Dy3+doped Zn2Y-type hexaferrite for potential technological applications.X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FTIR） and field-emission scanning electron microscopy（FESEM） were used to analyze structural *** crystallite size in the synthesized samples varies between 57.54 and 68.57 *** vibrational bands at 400 and 600 cm-1,common to all hexaferrites,were confirmed through *** FESEM analysis reveals an agglomeration of magnetic grains and a decrease in the average grain size from 1.24 to1.06 μ*** M-H loops show that,with x values of 0.0,0.1,and 0.2,the saturation magnetization is determined to be 34.76,34.23,and 32.52 emu/g,*** corresponding coercivity values are21.24,30.39,and 33.99 ***-visible spectroscopy using Tauc theory reveals an increase in the optical band gap from 2.32 to 2.50 eV,indicating a tunable energy band structure by incorporating Pr3+-Dy3+*** dielectric constant increases,whereas AC conductivity decreases with increased Pr3+-Dy3+*** obtained results suggest the potential suitability of these materials for various technological applications.

关键词： Dielectric constant Magnetic hysteresis Optical band gap Pr3+-Dy3+ Rare earths Zn2Y-type hexaferrite

Atezolizumab and bevacizumab combination in advanced hepatocellular carcinoma patients:The imperative for safety assessment studies

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World Journal of Clinical Cases 2025年第9期13卷 56-59页

作者： Mina Tharwat ahmed Tawheed mohamed El-Kassas Department of Tropical Medicine and Gastroenterology Faculty of MedicineAswan UniversityAswan 81528Egypt Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt

Hepatocellular carcinoma(HCC)is the most prevalent cancer of the hepatobiliary tract and the third leading cause of cancer-related mortality *** and bevacizumab combination is currently considered among the frontline treatment modalities for advanced unresectable *** studies examining this combination were focused on evaluating its *** numerous case reports documenting some side effects,there is a limited number of large-scale studies assessing these side *** this article,we comment on the case report by Park et al published recently,reporting a fatal intra-tumoral hemorrhage in a patient with HCC who received systemic therapy in the form of the combination of atezolizumab and bevacizumab.

关键词： Hepatocellular carcinoma Atezolizumab Bevacizumab Hemorrhage Side effects

Unexpected Diagnosis of an Intraoperative Riedel’s Thyroiditis and Analysis of Current Data

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International Journal of Otolaryngology and Head & Neck Surgery 2025年第1期14卷 68-75页

作者： Abdallah Witti Adou Kamil ahmed Kamil Filsan Absieh Bouh Nour Houmed mohamed Daoud Ali mohamed Mahyoub Abdallah Mahyoub Awaleh ahmed Awaleh Centre Mdico-Chirurgical de La Police Djibouti Djibouti Hpital Cheikho de Balbala Djibouti Djibouti

Background: Riedel’s thyroiditis is a rare form of chronic inflammatory disease affecting the thyroid gland. It is characterised by the replacement of the thyroid parenchyma by fibrous tissue. It also affects the adjacent vital structures. Due to its characteristic presentations, Riedel’s thyroiditis may not be immediately diagnosed. Objectives: Through this clinical case, we aimed to describe the pathology and clinical characteristics of Riedel’s thyroiditis and the diagnostic, therapeutic, and progressive modalities. Methods: A 62-year-old woman with no particular pathological history is consulted at the outpatient clinic for anterior cervical swelling that has been present for more than 5 years and is associated with respiratory discomfort and dysphagia to solids. Clinical examination, ultrasound, lab tests and injected cervical computed tomography (CT) were performed. These tests were completed with pathological examination. Results: General conditions were normal. Anterior cervical swelling, marked on the right, of hard consistency, causing cervical shielding with healthy surrounding skin, was observed at the examination. A compressive goitre was first suspected. Thyroid tests showed hypothyroidism. The CT revealed a hypodense goitre with micro-calcifications developed at the expense of the right lobe and exerting a mass effect on the trachea and oesophagus. Aspiration thyroid was not conclusive given the suspicion of the malignant nature of the goitre, and the decision to perform a right loboisthmectomy was taken. Pathological examination of the biopsy showed atrophy of the thyroid parenchyma with dense septal fibrosis punctuated by lymphocytes and extending throughout the tissue associated with inflammation—an appearance in favour of Riedel’s thyroiditis. The patient was treated with Levothyroxine and corticoids. Conclusions: This case points out the challenges in diagnosing Riedel’s Thyroiditis and the complexity of the pathology that requires a rigorous dia

关键词： Riedel’s Thyroiditis Diagnostic Challenges Hypothyroidism Compressive Symptoms Anapathology Djibouti

Experimental and parametrical investigation of pre-stressed ultrahigh-performance fiberreinforced concrete railway sleepers

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Frontiers of Structural and Civil Engineering 2023年第3期17卷 411-428页

作者： sayed ahmed Hossam ATEF mohamed HUSAIN Department of Structural Engineering Faculty of EngineeringZagazig UniversityZagazig 44519Egypt Track Work Department National Authority for TunnelsCairo 11522Egypt

In this study,ultrahigh-performance fiber-reinforced concrete(UHPFRC)used in a type B70 concrete sleeper is investigated experimentally and *** main parameters investigated are the steel fiber volume fractions(0%,0.5%,1%,and 1.5%).Under European standards,35 UHPFRC sleepers are subjected to static bending tests at the center and rail seat sections,and the screw on the fastening system is pulled *** first cracking load,failure load,failure mode,crack propagation,load–deflection curve,load–crack width,and failure load from these tests are measured and compared with those of a control sleeper manufactured using normal concrete *** accuracy of the parametric study is verified ***,the results of the study are applied to UHPFRC sleepers with different concrete volumes to investigate the effects of the properties of UHPFRC on their *** and parametric study results show that the behavior of UHPFRC sleepers improves significantly when the amount of steel fiber in the mix is *** manufactured using UHPFRC with a steel fiber volume fraction of 1%and a concrete volume less than 25%that of standard sleeper B70 can be used under the same loads and requirements,which contributes positively to the cost and surrounding environment.

关键词： pre-stressed concrete sleeper ultrahigh performance fiber-reinforced concrete pull-out test static bending test steel fiber aspect ratio volume fraction

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Evaluation of the Effectiveness of Traditional and Nano Materials Used in Consolidation of Sandstone Used in Ramesses III Temple, Karnak, Egypt

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Journal of Minerals and Materials Characterization and Engineering 2025年第1期13卷 18-30页

作者： Essam H. mohamed Zeinab Mahmoud ahmed Mahmoud L. Abd El-Latif Department of Archaeological Conservation Faculty of Archaeology South Valley University Qena Egypt Department of Conservation Faculty of Archaeology South Valley University Qena Egypt Housing and Building Research Center Giza Egypt

This experimental study assesses the effectiveness of traditional and nano-materials in enhancing the physical and mechanical properties of deteriorated sandstone from Ramesses III Temple, Karnak, Luxor, Egypt. Treatments included Nano Estel (5%), Paraloid B-72 (3%), Paraloid B-72/Nano Estel (3%/5%), and ethyl silicates. Treated samples underwent Scanning Electron Microscopy (SEM) and physical/mechanical testing. Results show that Paraloid B-72/Nano Estel (3%/5%) yielded optimal consolidation, significantly improving sandstone’s physical and mechanical properties.

关键词： Ramesses III Temple Deteriorated Sandstone Consolidation Treatments Nano Material Physical and Mechanical Properties

SYNTHESIS,CHARACTERIZATION AND ENHANCED ELECTRICAL PROPERTIES OF CTAB-DIRECTED POLYANILINE NANOPARTICLES

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Chinese Journal of Polymer Science 2011年第2期29卷 181-190页

作者： Lal said Jan mohamed ahmed Siddig Department of Physics Postgraduate College Mardan23200Khyber PakhtunkhwaPakistan School of Physics and Applied Physics Faculty of Science and TechnologyEL Neelain UniversityKhartoumSudan

Inverse microemulsion system of cetyltrimethylammonium bromide（CTAB） molecules is utilized for virtually monodispersed and controlled growth of HCl polyaniline（PANI） nanoparticles at room temperature（ca.300 K）.The templated electroconductive polymer reveals lamellar crystalline structure under X-ray diffraction signifying marked sub-chain alignment of the polymerized *** nanostructured polymer has spherically symmetric morphology in a size range of 2.0 nm to 6.0 nm under electron microscope *** permeation chromatography gives polydispersity index of 1.02 for nanostructured polymer in agreement with the size monodispersity transpired by electron *** *** conductivityσ_（dc） of PANI at room temperature is 10.11 S/cm whereas the variation of conductivity with temperature in the range 227-303 *** that the conducting mechanism can be considered as three-dimensional variable-range-hopping（3D-VRH）.UV-Vis spectrum indicates two broad absorption bands due to polaron formation that contributes to enhanced electrical conductivity of the *** fundamental absorption edge in the polymer is formed by direct allowed transitions to the extent that the optical band gap value was found to be 2.35 *** crystalline nanostructure and homogeneous doping attained in the cationic template of amphiphile are argued as contributing factors to the enhanced conductivity of the polymer.

关键词： Polyaniline Nanostructured Band gap energy Electrical conductivity