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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO s.el-BORGI school of Mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMs)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMs) dispersion phase velocity

Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern saudi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mansour H.Al-Hashim Abdelbaset s.el-sorogy Meshal Wadani Department of Geology and Geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation comprises a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red sea, northwestern saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analyses were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analysis reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenesis and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in sr and Ca levels and increase in Mg,Na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenesis Geochemistry saudi Arabia

Large magnetocaloric effect and magnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： M.Lassri M.sajieddine A.elouafi A.el Hachmi s.el Ouahbi R.Moubah Laboratory of Energy and Materials Engineering (LGEM) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-school of Industrial Management (EMINEs) Mohammed Ⅵ Polytechnic University National school of Applied sciences (ENsA) University of Sultan Moulay Slimane Laboratory of Mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on Matter and Instrumentation (LRMI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced Materials and Thermic (LPMAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPs）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔsM),was determined by em ploying the thermodynam ic Maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔsMand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： X-ray photoelectron spectroscopy Cryogenic magnetic refrigeration Magnetic properties Magnetocaloric effect Rare earths

Genetic Variability and Phenotypic Correlations study among Grain Quality Traits and Mineral elements Concentrations in Colored and Non-Colored Rice (Oryza sativa L.)

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1733-1748页

作者： Adel A.Rezk Mohamed M.el-Malky Heba I.Mohamed Hossam s.el-Beltagi Agricultural Biotechnology Department College of Agricultural and Food ScienceKing Faisal UniversityAl-Ahsa31982Saudi Arabia Plant Pathology Research Institute Agriculture Research CenterGiza12619Egypt Rice Research and Training Center Field Crop Research InstituteAgriculture Research Center33717Egypt Biological and Geological sciences Department Faculty of EducationAin Shams UniversityCairo11511Egypt Biochemistry Department Faculty of AgricultureCairo UniversityGiza12613Egypt

Twenty-four rice genotypes were examined to assess genetic variability,heritability,and correlations for seven-grain quality traits,eight nutritional elements,and *** revealed signiﬁcant differences for the quality traits *** every trait under study,the phenotypic coefﬁcient of variation was higher than the correspon-dence genotypic coefﬁcient of *** in a broad sense varied from 29.75%for grain length to 98.31%for the elongation *** percentage recovery had a highly signiﬁcant positive correlation with milling and head rice ***,milling percentage had a highly positive correlation with head rice *** amylose percentage,all the genotypes belonged to low amylose except the Hassawi-1 variety,which had intermediate amylose *** nutrition contents of magnesium(Mg),sodium(Na),potas-sium(K),calcium(Ca),copper(Cu),manganese(Mn),zinc(Zn),iron(Fe),or protein percentage gave different variations for 24 rice genotypes under all the nutritional *** the 24 genotypes,ten rice genotypes–HighNutrient-1,HighNutrient-2,HighNutrient-9,HighNutrient-8,HighNutrient-3,Hassawi-2,HighNutrient-7,HighNutrient-6,Hassawi-1,and HighNutrient-4–had the highest heist value for all nutritional and protein con-tents,and could be used as a donor to improving new *** was a positive and signiﬁcant correlation between magnesium Mg,K,Zn and ***,K had a positive correlation with zinc Zn,Fe,and protein *** analysis was divided into two groups:theﬁrst group included all genotypes rich in nutri-ents,while the remaining genotypes with low nutritional content were included in the second group.

关键词： Amylose cluster analysis genotypes grain quality mineral nutrition rice

Intravesical instillation of platelet-rich plasma for treatment of interstitial cystitis/bladder pain syndrome:A pilot study

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Current Urology 2024年第1期18卷 49-54页

作者： Ahmed s.el Hefnawy Mohamed Attya Ahmed Hasan Esam el sawy Mohamed Abdel-Razik Nasr el-Tabey Mansoura Urology and Nephrology Center Faculty of MedicineMansoura UniversityMansouraEgypt

Objective:The aim of this study was to evaluate the feasibility of intravesical instillation of platelet-rich plasma(PRP)to treat interstitial cystitis/bladder pain syndrome(IC/BPs).Materials and methods:Twenty PRP samples were tested in vitro for stability after exposure to urine samples with different pH.A pilot study involving 21 female patients with IC/BPs was conducted,and 6 weekly doses of autologous PRP(50 mL)were *** were followed up at the 2nd,4th,8th,and 12th weeks after terminating *** primary endpoint was the visual analog scale(VAs)for pain,and the secondary endpoints included the IC symptom index,IC problem index of the O'Leary-sant questionnaire and global response assessment,urine culture,and *** was defined as a reduction in VAs by 30%or more compared with basal level,and adverse events were ***:The mean±sD of VAs was significantly reduced compared with basal level(4.4±2.6 vs.8.8±1.1,respectively,p=0.001).Meanwhile,80%of cases were considered successful,with a 50.1%reduction in the mean score compared with the basal *** mean±sD of IC symptom index and IC problem index significantly improved compared with the basal *** response assessment was markedly,moderately,and slightly improved in 2(10%),10(50%),and 5(25%)patients,respectively,and showed no change in 3(15%).Three patients had positive urine cultures at follow-up,but 1 withdrew after 2 sessions because of a lack of ***:Repeated intravesical instillation of PRP could be considered an effective and safe approach for treating IC/BPs.

关键词： Bladder pain syndrome Interstitial cystitis Platelet-rich plasma

Large magnetocaloric effect and magnetic properties of EuRhO_(3)

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Journal of Rare Earths 2024年第9期42卷 1724-1729,I0004页

作者： M.Lassri M.sajieddine A.elouafi A.el Hachmi s.el Ouahbi R.Moubah Laboratory of Energy and Materials Engineering(LGEM) University of Sultan Moulay SlimaneFaculty of Science and Technology(FST)BP 52323000Béni-MellalMorocco Institute of Applied Physics(IAP)-school of Industrial Management(EMINEs) Mohammed Ⅵ Polytechnic UniversityHay Moulay RachidLot 6603150Ben GuerirMorocco National school of Applied sciences(ENsA) University of Sultan Moulay SlimaneBP 7725000KhouribgaMorocco Laboratory of Mechanics Production and Industrial Engineering(LMPGI)Higher School of Technology of Casablanca(ESTC)University of Hassan Ⅱ CasablancaCasablancaMorocco Laboratory of Radiation on Matter and Instrumentation(LRMI) Faculty of Science and Technology(FST)SettatHassan Ⅰ UniversitySettatMorocco Laboatory of Physics of Advanced Materials and Thermic(LPMAT) Faculty of Science Ain Chock(FSAC)University of Hassan Ⅱ CasablancaCasablancaMorocco

We report on the structural,magnetic,and magnetocaloric properties of EuRhO_(3) *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy(XPs).It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***_(3) powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature(T_(N)=2.9 K).Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/(T-θ_(W))) for T>T_(N),yields θ_(W)=-3.1 K and effective magne tic moment μ_(ff)^(exp),which is close to the theoretical value μ_(eff)^(theo).The magnetic entropy change(-Δ_(sM)),was determined by em ploying the thermodynam ic Maxwell's *** μ_0H=5 T and near T_(N),Δs_(M)^(Max) and relative cooling power(RCP) exhibit large values of 33.7 J/(kg·K) and 238 J/kg,*** large magnitude of-Δ_(sM) and RCP show that the EuRhO_(3) compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： X-ray photoelectron spectroscopy Cryogenic magnetic refrigeration Magnetic properties Magnetocaloric effect Rare earths

suitability of sDN and MEC to facilitate digital twin communication over LTE-A

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Digital Communications and Networks 2024年第2期10卷 347-354页

作者： Hikmat Adhami mohammad Alja’afreh Mohamed Hoda Jiaqi Zhao Yong Zhou Abdulmotaleb el saddik Mohamed bin Zayed University of Artificial Intelligence Masdar CityAbu DhabiUnited Arab Emirates school of Computer science and Technology China University of Mining and TechnologyXuzhou221116China school of electrical Engineering and Computer science University of OttawaOttawaONK1N 6N5Canada

Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control *** will require ultra-low latency and ultra-high reliability to evolve the mobile experience into the era of Digital Twin and Tactile *** the 5th generation of mobile networks is not yet widely deployed,Long-Term Evolution(LTE-A)latency remains much higher than the 1 ms requirement for the Tactile Internet and therefore the Digital *** work investigates an interesting solution based on the incorporation of software-defined networking(sDN)and Multi-access Mobile Edge Computing(MEC)technologies in an LTE-A network,to deliver future multimedia applications over the Tactile Internet while overcoming the Qos *** network scenarios were designed and simulated using Riverbed modeler and the performance was evaluated using several time-related Key Performance Indicators(KPIs)such as throughput,End-2-End(E2E)delay,and *** best scenario possible is clearly the one integrating MEC and sDN approaches,where the overall delay,jitter,and throughput for haptics-attained 2 ms,0.01 ms,and 1000 packets per *** results obtained give clear evidence that the integration of,both sDN and MEC,in LTE-A indicates performance improvement,and fulfills the standard requirements in terms of the above KPIs,for realizing a Digital Twin/Tactile Internet-based system.

关键词： LTE-A 5G Digital twin Tactile Internet KPIs sDN MEC NFV Haptic

Thermodynamic Performance Analysis of Geothermal Power Plant Based on Organic Rankine Cycle (ORC) Using Mixture of Pure Working Fluids

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Energy Engineering 2024年第8期121卷 2023-2038页

作者： Abdul sattar Laghari mohammad Waqas Chandio Laveet Kumar Mamdouh el Haj Assad Department of Mechanical Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of Mechanical and Industrial Engineering College of EngineeringQatar UniversityDoha00000Qatar sustainable&Renewable Energy Engineering Department University of SharjahSharjah00000United Arab Emirates

The selection of working fluid significantly impacts the geothermal ORC’s *** a mixture as a working fluid is a strategy to improve the output of geothermal *** the current study,modelling and thermodynamic analysis of ORC,using geothermal as a heat source,is carried out at fixed operating *** model is simulated in the Engineering Equation solver(EEs).An environment-friendly mixture of fluids,i.e.,R245fa/R600a,with a suitable mole fraction,is used as the operating *** mixture provided the most convenient results compared to the pure working fluid under fixed operating *** impact of varying the evaporator pressure on the performance parameters,including energy efficiency,exergy efficiency and net power output is *** system provided the optimal performance once the evaporator pressure reached the maximum *** efficiencies:Energy and Exergy,and Net Power output of the system are 16.62%,64.08%and 2199 kW for the basic cycle and 20.72%,67.76%and 2326 kW respectively for the regenerative cycle.

关键词： Organic rankine cycle internal heat exchanger moderate-temperature geothermal source mixture of the fluid exergy

Gut microbiota predicts the diagnosis of ulcerative colitis in saudi children

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World Journal of Clinical Pediatrics 2024年第1期13卷 118-124页

作者： mohammad el Mouzan Ahmed Al sarkhy Asaad Assiri Department of Pediatrics Gastroenterology UnitKing Saud UniversityRiyadh 11461Saudi Arabia

BACKGROUND Ulcerative colitis(UC)is an immune-mediated chronic inflammatory condition with a worldwide *** the etiology of this disease is still unknown,the understanding of the role of the microbiota is becoming increasingly *** To investigate the predictive power of the gut microbiota for the diagnosis of UC in a cohort of newly diagnosed treatment-naïve saudi children with *** The study population included 20 children with a confirmed diagnosis of UC and 20 healthy *** DNA was extracted and sequenced,and shotgun metagenomic analysis was performed for bacteria and *** and bioinformatics demonstrated significant dysbiosis in the form of reduced alpha diversity,beta diversity,and significant difference of abundance of taxa between children with UC and control *** receiver operating characteristic curve,a probability curve,was used to determine the difference between the UC and control *** area under the curve(AUC)represents the degree of separability between the UC group and the control *** AUC was calculated for all identified bacterial species and for bacterial species identified by the random forest classification algorithm as important potential biomarkers of UC.A similar method of AUC calculation for all bacteriophages and important species was *** The median age and range were 14(0.5-21)and 12.9(6.8-16.3)years for children with UC and controls,respectively,and 40%and 35%were male for children with UC and controls,*** AUC for all identified bacterial species was 89.5%.However,when using the bacterial species identified as important by random forest classification algorithm analysis, the accuracy increased to 97.6%. similarly, the AUC for all theidentified bacteriophages was 87.4%, but this value increased to 94.5% when the important bacteriophagebiomarkers were *** very high to excellent AUCs of fecal bacterial and viral species sugge

关键词： Ulcerative colitis Microbiota Area under the curve Children saudi Arabia