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The Upper Jurassic sediments,marib-Shabwa Basin,Yemen:Lithofacies aspects and sequence stratigraphic analysis

Energy Geoscience 2024年第1期5卷 342-357页

作者： mohammed Albaroot mohamed m.elhossainy Nabil m.Al-Areeq Emad A.Abdullah Abdelhamid m.Salman Department of Applied Geology Faculty of Science and EducationUniversity of Saba RegionMaribYemen Department of Geology Faculty of ScienceKafrelsheikh UniversityKafrelsheikh33516Egypt Department of Geology and Environment Faculty of Applied SciencesThamar UniversityYemen Department of mineral Developing and Oil&Gas Engineering Academy of EngineeringPeoples’Friendship University of Russia(RUDN University)Moscow117198Russia Department of Geology Faculty of ScienceAssiut UniversityAssiut71516Egypt

The present study is devoted to understanding the evolution of the Upper Jurassic Sab'atayn Formation in the marib-Shabwa Basin,Yemen,through a sequence stratigraphic analysis based on integrating datasets of sedimentology,seismic sections,and well *** Sab'atayn Formation(Tithonian age)is represented by a series of clastic and evaporites that were deposited under fluvio-deltaic to prodeltaic *** is divided into four members including Yah(at the base),upwards to Seen,Alif,and Safir at the *** third-order depositional sequences were determined for the Tithonian succession which were separated by three sequence *** sequences were classified into their systems tracts signifying several sedimentation patterns of progradational,aggradational,and retrogradational parasequence *** first depositional sequence corresponds to the early-middle Tithonian Yah and Seen units that can be classified into lowstand,transgressive,and highstand systems *** second sequence comprises the late Tithonian Alif unit that can be subdivided into transgressive and highstand systems *** sandy deposits of the Alif member(highstand deposits)represent the most productive hydrocarbon reservoir in the *** Upper Jurassic sediments in the study area were resulted from a combination of eustatic and tectonic effects.

关键词： Sequence stratigraphy Sandstone reservoir Well logs Upper Jurassic marib-Shabwa Basin Yemen

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埃及Burullus潟湖沉积生源要素变化:百年来人类活动影响

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沉积学报 2020年第6期38卷 1249-1257页

作者：麻福伟李茂田刘演赵小双陈中原 Alaa Salem Abu ShamaA.m mohamed m.elhossainy 华东师范大学河口海岸学国家重点实验室上海200062 Geological Sciences Department Kafrelsheikh UniversityKafrelsheikh 33516Egypt

Burullus是尼罗河河口高封闭性潟湖,其生源要素主要来源于尼罗河,是研究Aswan大坝建成以来流域变化如何影响河口湖泊环境的最佳区域。研究通过对Burullus潟湖B1岩芯的210Pb测年、粒度、以及TOC、TN、TP、BSi生源要素的测试分析,结合历... 详细信息

Burullus是尼罗河河口高封闭性潟湖,其生源要素主要来源于尼罗河,是研究Aswan大坝建成以来流域变化如何影响河口湖泊环境的最佳区域。研究通过对Burullus潟湖B1岩芯的210Pb测年、粒度、以及TOC、TN、TP、BSi生源要素的测试分析,结合历史资料,试图揭示Aswan建坝前后河口湖泊营养盐的差异变化,以及这些变化对生态环境的影响。结果表明:1)沉积物中TOC、TN和TP含量自下而上总体增加,表明尽管Aswan大坝导致营养盐通量急剧减少,但由于下游人类排放N、P通量大大增加,导致下游湖泊N、P浓度并没减少;且沉积TN/TP均小于16,表明湖泊仍为P限制。2)但BSi和BSi/TOC自下而上总体呈减少趋势,表明Aswan大坝引起的水沙减少导致湖泊中硅藻的生物量及其总初级生产力占比都在减少,潟湖水体生态环境将趋于恶化。

关键词：营养盐人类活动 Aswan大坝 Burullus潟湖

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The impact of alpha-fetoprotein (AFP), child-turcotte-pugh (CTP) score and disease staging on the survival of hepatocellular carcinoma (HCC) patients: a retrospective cohort from single oncology center

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Oncology research 2025年第1期33卷 149-160页

作者： Nasser mulla Yousef Katib Asim m Almughamsi Duaa S Alkhayat mohamed mosaad Samir T Alfotih Rawan Alaofi Department of Internal medicine Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Radiology Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Surgery Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Endemic and Infectious Diseases Suez Canal University Ismailia 41522 Egypt. King Salman bin Abdulaziz medical City Madinah 42311 Saudi Arabia. Prince mohammed Bin Abdulaziz Hospital Madinah 41511 Saudi Arabia.

Background:Hepatocellular carcinoma (HCC) is the most common cause of cancer-related death in Saudi Arabia. Our study aimed to investigate the patterns of HCC and the effect of TNm staging, Alfa-fetoprotein (AFP), and Child-Turcotte Pugh (CTP) on patients' overall survival (OS).methods:A retrospective analysis was conducted on 43 HCC patients at a single oncology center in Saudi Arabia from 2015 to 2020. All patients had to fulfill one of the following criteria: (a) a liver lesion reported as definitive HCC on dynamic imaging and/or (b) a biopsy-confirmed diagnosis.Results:The mean patient age of all HCC cases was 66.8 with a male-to-female ratio of 3.3:1. All patients were stratified into two groups: viral HCC (n = 22, 51%) and non-viral HCC (n = 21, 49%). Among viral-HCC patients, 55% were due to HBV and 45% due to HCV. Cirrhosis was diagnosed in 79% of cases. Age and sex did not significantly statistically differ in OS among viral and non-viral HCC patients (-value > 0.05). About 65% of patients had tumor size >5 cm during the diagnosis, with a significant statistical difference in OS (-value = 0.027). AFP was >400 ng/ml in 45% of the patients. There was a statistically significant difference in the OS in terms of AFP levels (-value = 0.021). A statistically significant difference was also observed between the CTP score and OS (-value = 0.02). CTP class B had the longest survival. BSC was the most common treatment provided to HCC patients followed by sorafenib therapy. There was a significant statistical difference in OS among viral and non-viral HCC patients (-value = 0.008).Conclusions:The most common predictors for OS were the underlying cause of HCC, AFP, and tumor size. Being having non-viral etiology, a tumor size >5 cm, an AFP > 400 ng/mL, and a CTP score class C were all negatively associated with OS.

关键词： Alpha-fetoprotein (AFP) Child-turcotte-pugh Hepatocellular carcinoma Pattern Progression free survival

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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

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Small heat shock protein B8:from cell functions to its involvement in diseases and potential therapeutic applications

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Neural Regeneration Research 2025年第10期20卷 2872-2886页

作者： marta Chierichetti Riccardo Cristofani Valeria Crippa Veronica Ferrari marta Cozzi Elena Casarotto Paola Pramaggiore Laura Cornaggia Guglielmo Patelli Ali mohamed margherita Piccolella mariarita Galbiati Paola Rusmini Barbara Tedesco Angelo Poletti Laboratory of Experimental Biology Dipartimento di Scienze Farmacologiche e Biomolecolari“Rodolfo Paoletti”(DiSFeB)Universitàdegli Studi di MilanoMilanItaly

Heat shock protein family B(small)member 8(HSPB8)is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock ***8 is involved in various cellular mechanisms mainly related to proteotoxic stress response and in other processes such as inflammation,cell division,and ***8 binds misfolded clients to prevent their aggregation by assisting protein refolding or degradation through chaperone-assisted selective *** line with this function,the pro-degradative activity of HSPB8 has been found protective in several neurodegenerative and neuromuscular diseases characterized by protein misfolding and *** cancer,HSPB8 has a dual role being capable of exerting either a pro-or an anti-tumoral activity depending on the pathways and factors expressed by the model of cancer under ***,HSPB8 exerts a protective function in different diseases by modulating the inflammatory response,which characterizes not only neurodegenerative diseases,but also other chronic or acute conditions affecting the nervous system,such as multiple sclerosis and intracerebellar *** note,HSPB8 modulation may represent a therapeutic approach in other neurological conditions that develop as a secondary consequence of other *** is the case of cognitive impairment related to diabetes mellitus,in which HSPB8 exerts a protective activity by assuring mitochondrial *** review aims to summarize the diverse and multiple functions of HSPB8 in different pathological conditions,focusing on the beneficial effects of its ***-based and alternative therapeutic approaches targeting HSPB8 and its regulated pathways will be discussed,emphasizing how new strategies for cell and tissue-specific delivery represent an avenue to advance in disease treatments.

关键词： aggregation autophagy cancer chaperone chaperone-assisted selective autophagy cognitive impairment HSPB8 neuroinflammation neuromuscular diseases therapy

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An unstructured mesh method for numerical simulation of violent sloshing flows

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Journal of Hydrodynamics 2020年第2期32卷 259-266页

作者： Changhong Hu mohamed m.Kamra Research Institute for Applied mechanics Kyushu UniversityFukuokaJapan

An unstructured mesh Reynolds-averaged Navier-Stokes(RANS)solver has been developed for numerical simulation of violent sloshing flows inside a tank with complicated inner *** numerical solver employs the unstructured multi-dimensional tangent hyperbolic interface capturing method(UmTHINC)for free-surface capturing combined with various turbulence *** sloshing motion is numerically modeled using the body-force method which introduces a source term into the momentum equation corresponding to the tank motion *** simulations of the tank sloshing problems are performed for different test cases with various oscillation *** performance of the interface capturing method has been discussed and the effect of turbulence model choice on loading predictions is highlighted by studying several RANS models and analyzing its effect on fluid motion and impact *** simulations of the sloshing inside the tank with a vertical baffle has also been conducted and a discussion is provided on different numerical treatment of the baffle.

关键词： Unstructured mesh RNAS solver UmTHINC scheme violent sloshing flow

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Exploration of structural,optical,and photoluminescent properties of (1-x)NiCo_(2)O_(4)/xPbS nanocomposites for optoelectronic applications

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Chinese Physics B 2022年第6期31卷 663-670页

作者： Zein K Heiba mohamed Bakr mohamed Noura m Farag Ali Badawi Physics Department Faculty of ScienceAin Shams UniversityCairoEgypt Physics Department Faculty of ScienceTaibah UniversityAl-Madina al MunawarahSaudi Arabia Department of Physics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Physics University College of TurabahTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

The(1-x)NiCo_(2)O_(4)/x PbS(0≤x≤0.2)nanocomposite samples are synthesized using the hydrothermal and thermolysis *** different phases developed in the obtained nanocomposite samples are accurately determined using the x-ray diffraction technique equipped with a *** percentage of the formed phases(NiCo_(2)O_(4)(NCO),PbS,PbSO_(4)),structural and microstructure parameters are determined using Rietveld quantitative phase *** transmission electron microscope(TEm)images and Rietveld analysis reveal almost isotropic particle size in the nano range with a very narrow size *** obtained phase percentage of PbS and PbSO4are smaller than nominated values(x)suggesting dissolving of some Pb and S ions into NCO which is then confirmed by the analysis of Fourier-transform infrared(FTIR)spectra of nanocomposite *** absorption spectra are modified upon doping NCO with *** optical band gaps of the nanocomposites increase as the amount of PbS *** effect of alloying on extinction coefficient,refractive index,dielectric constant,optical conductivity,the intensity,and emitted color from the photoluminescence of the nanocomposite samples are also *** refractive index value of NCO and NCO-PbS nanocomposite samples exhibit normal *** photoluminescent measurements reveal that the NCO-PbS nanocomposites can emit a violet *** improvement in the values of the nonlinear optical(NLO)parameters of pristine NCO at high frequencies or the nanocomposite samples at low frequencies,are made them used in NLO photonic devices.

关键词： Co_(2)O_(4)and PbS nanocomposite FTIR optical photoluminescence

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microstructure and mechanical properties of hot extruded 6016 aluminum alloy/graphite composites

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Journal of materials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed m.El-Sayed Seleman mohamed m.Z.Ahmed Sabbah Ataya Department of metallurgical and materials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai metallurgical and materials Research Center of Scientific Excellence (SSmmR-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Department of mechanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 aluminum alloy matrix to fabricate metal/ceramic composites is still a great challenge and various parameters should be considered. In this study, dense AA6016 aluminum alloy/（0-20 wt%） graphite composites have successfully been fabricated by powder metallurgy process. At first, the mixed aluminum and graphite powders were cold compacted at 200 mPa and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceramic phases（free graphite and in-situ formed carbides） on microstructure, physical and mechanical properties of the produced composites were finally investigated. The results show that the fabricated composites have a relative density of over 98%. SEm observations indicate that the graphite has a good dispersion in the alloy matrix even at high graphite content. Hardness of all the produced composites was higher than that of aluminum alloy matrix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultimate tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite composites were determined by high precision second order equations. Both compressive and ultimate tensile strengths have been correlated to microstructure constituents with focusing on the in-situ formed ceramic phases, silicon carbide（SiC） and aluminum carbide（Al4 C3）. The ductile fracture mode of the produced composites became less dominant with increasing free graphite content and in-situ formed carbides. Wear resistance of Al/graphite composites was increased with increasing graphite content. Aluminum/20 wt% graphite composite exhibited superior wear resistance over that of AA6016 aluminum alloy.

关键词： AA6016/graphite composites Hot extrusion In-situ carbides mechanical properties Wear resistance Fracture behavior

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Linearly and Quadratically Separable Classifiers Using Adaptive Approach

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Journal of Computer Science & Technology 2011年第5期26卷 908-918页

作者： mohamed Abdel-Kawy mohamed Ali Soliman Rasha m.Abo-Bakr Department of Computer and Systems Engineering Faculty of EngineeringZagazig UniversityZagazigEgypt Departement of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

This paper presents a fast adaptive iterative algorithm to solve linearly separable classification problems in R *** each iteration,a subset of the sampling data （n-points,where n is the number of features） is adaptively chosen and a hyperplane is constructed such that it separates the chosen n-points at a margin and best classifies the remaining *** classification problem is formulated and the details of the algorithm are ***,the algorithm is extended to solving quadratically separable classification *** basic idea is based on mapping the physical space to another larger one where the problem becomes linearly *** illustrations show that few iteration steps are sufficient for convergence when classes are linearly *** nonlinearly separable data,given a specified maximum number of iteration steps,the algorithm returns the best hyperplane that minimizes the number of misclassified points occurring through these *** with other machine learning algorithms on practical and benchmark datasets are also presented,showing the performance of the proposed algorithm.

关键词： linear classification quadratic classification iterative approach adaptive technique

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Processing of Ceramic Based Nanocomposite Usingα-Al_2O_3 Powder and FeCl_2 Solution as Starting materials

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Journal of materials Science & Technology 2007年第6期23卷 837-842页

作者： mohamed m.EL-Sayed Seleman Department of materials and metallurgical Engineering Faculty of Petroleum and Mining EngineeringPost Code 43721SuezEgypt

Alumina-iron nanocomposite powders were prepared by a two-step process. In the first step, α-Al2O3-FeCl2 powder mixture was formed by mixing α-Al2O3 powders with FeCl2 solution followed by drying. In the second step, the FeCl2 in the dry power mixture was selectively reduced to iron particles. A reduction temperature of 750℃ for 15 min in dry H2 was chosen based on the thermodynamic calculations. The concentration of iron in FeCl2 solution was calculated to be 20 vol. pct in the final composite. Two techniques were used to produce composite bulk materials. The Al2O3 nanocomposite powders were divided to two batches. The first batch of the produced mixture was hot pressed at 1400℃ and 27 mPa for 30 min in a graphite die. To study the effect of oxygen on the Al2O3/Fe interface bonding and mechanical properties of the composite, the second batch was heat treated in air at 700℃ for 20 min to partially oxidize the iron particles before hot pressing. Characterization of the composites was undertaken by conventional density measurements, X-ray diffractometry （XRD）, scanning electron microscopy （SEm）, transmission electron microscopy （TEm） and electron probe micro analysis （EPmA）. The suggested processing route （mixing, reduction and hot pressing） produces ceramic-metal nanocomposite much tougher than the pure Al2O3. The fracture strength of the produced Al2O3/Fe nanocomposite is nearly twice that of the pure Al2O3. The presence of spinel phase, FeAl204, as thick layer around the Fe particles in the Al2O3 matrix has a detrimental effect on interfacial bonding between Fe and AI203 and the fracture properties of the composite.

关键词： Ferrous chloride Reduction Alumina-iron nanocomposite Spinel phase

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