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Journal of Control and Decision 2023年第4期10卷 538-546页

作者： k.Ramkumar k.Ravikumar e.M.elsayed Department of Mathematics with CA PSG College of Arts&ScienceCoimbatoreIndia Department of Mathematics PSG College of Arts&ScienceCoimbatoreIndia Department of Mathematics Faculty of ScienceKing Abdulaziz UniversityJeddahSaudi Arabia Department of Mathematics Faculty of ScienceMansoura UniversityMansouraEgypt

In this work,the optimal control for a class of Hilfer fractional stochastic integrodifferential systems driven by Rosenblatt process and Poisson jumps has been discussed in infinite dimensional space involving the Hilfer fractional ***,we study the existence and uniqueness of mild solution results are proved by the virtue of fractional calculus,successive approximation method and stochastic analysis ***,the optimal control of the proposed problem is presented by using Balder’s ***,an example is demonstrated to illustrate the obtained theoretical results.

关键词： Hilfer fractional derivative stochastic integrodifferential systems Rosenblatt process Poisson jumps successive approximation optimal control

enhanced dielectric performance of Dy-substituted YMn2O5 for high-frequency applications

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Progress in Natural Science:Materials International 2021年第5期31卷 762-771页

作者： H.Chouaibi k.khirouni e.Dhahri Laboratoire de Physique Appliquée Faculté des Sciences Université de Sfax Laboratoire de Physique des Matériaux et des Nanomatériaux Appliquée à l'environnement Faculté des Sciences de Gabès Cité Erriadh Université de Gabès

The dielectric performances as well as the effects of Dy3+ions content at A sites of YMn2O5（YMO） [x=0（YDM0）and x=0.4(YDM0.4)] polycrystalline samples were *** compounds were synthesized via sol-gel method.X-Ray diffraction and Raman measurements proved the high quality of the compounds that crystallized in an orthorhombic structure with the Pbam space ***,impedance spectroscopy and electrical modulus studies revealed that both samples exhibited a non-Debye's type of *** decrease of impedance for YDM0.4compared to the pure YDM0,may be attributed to the decrease in charge transfer *** the fit of impedance spectra,they confirmed that both compounds were simultaneously capacitive and ***,the activation energies obtained from Modulus and complex impedance were proven to be neighboring,suggesting that the relaxation process refers to electron *** each compound,the evolution of ε'and tan & with temperature indicated a clearer relaxor behavior,namely the existence of two *** first one detected at low temperature is related to the charge carriers hopping between Mn3+and Mn4+and the second at high temperature is associated with oxygen *** reduced hopping rate with Dy3+substitution for Y3+ions at A sites is responsible for the decrease in dielectric constant and dielectric *** significant findings demonstrate that these materials can be invested in a fruitful use in UV photo-detector and power applications in high frequency as microwave,millimeter wave signal processing,for civilian,military and space applications.

关键词： Multiferroic Relaxation phenomenon High dielectric constant Relaxor behavior

Inflammasome links traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1644-1664页

作者： Gabriela Seplovich Yazan Bouchi Juan Pablo de Rivero Vaccari Jennifer C.Munoz Pareja Andrew Reisner Laura Blackwell Yehia Mechref kevin k.Wang J.Adrian Tyndall Binu Tharakan Firas kobeissy Department of Surgery Morehouse School of MedicineAtlantaGAUSA Department of Neurobiology Center for NeurotraumaMultiomics&Biomarkers(CNMB)Neuroscience InstituteMorehouse School of MedicineAtlantaGAUSA Department of Neurological Surgery and the Miami Project to Cure Paralysis University of Miami Miller School of MedicineMiamiFLUSA Division of Pediatric Critical Care Department of PediatricsUniversity of Miami Miller School of MedicineMiamiFLUSA Department of Pediatrics Emory UniversityAtlantaGAUSA Department of Neurosurgery Children’s Healthcare of AtlantaAtlantaGAUSA Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTXUSA Morehouse School of Medicine AtlantaGAUSA

Traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease are three distinct neurological disorders that share common pathophysiological mechanisms involving neuroinflammation. One sequela of neuroinflammation includes the pathologic hyperphosphorylation of tau protein, an endogenous microtubule-associated protein that protects the integrity of neuronal cytoskeletons. Tau hyperphosphorylation results in protein misfolding and subsequent accumulation of tau tangles forming neurotoxic aggregates. These misfolded proteins are characteristic of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease and can lead to downstream neuroinflammatory processes, including assembly and activation of the inflammasome complex. Inflammasomes refer to a family of multimeric protein units that, upon activation, release a cascade of signaling molecules resulting in caspase-induced cell death and inflammation mediated by the release of interleukin-1β cytokine. One specific inflammasome, the NOD-like receptor protein 3, has been proposed to be a key regulator of tau phosphorylation where it has been shown that prolonged NOD-like receptor protein 3 activation acts as a causal factor in pathological tau accumulation and spreading. This review begins by describing the epidemiology and pathophysiology of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease. Next, we highlight neuroinflammation as an overriding theme and discuss the role of the NOD-like receptor protein 3 inflammasome in the formation of tau deposits and how such tauopathic entities spread throughout the brain. We then propose a novel framework linking traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease as inflammasomedependent pathologies that exist along a temporal continuum. Finally, we discuss potential therapeutic targets that may intercept this pathway and ultimately minimize long-term neurological decline.

关键词： Alzheimer's disease caspase-1 chronic traumatic encephalopathy inflammasomes neurodegeneration neuroinflammation NLRP1 NLRP3 pyroptosis tauopathy traumatic brain injury

FRee TRANSVeRSe VIBRATIONS OF A DOUBLe-WALLeD CARBON NANOTUBe:GRADIeNT AND INTeRNAL INeRTIA eFFeCTS

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Acta Mechanica Solida Sinica 2014年第4期27卷 345-352页

作者： k.Y.Xu k.A.Alnefaie N.H.Abu-Hamdeh k.H.Almitani e.C.Aifantis Department of Mechanics Shanghai University Department of Mechanical engineering King Abdulaziz University Jeddah 21589 Saudi Arabia Lab of Mechanics and Materials Polytechnic School Aristotle University Thessaloniki 54124 Greece

This is a modest contribution on higher-order continuum theory for predicting size effects in small-scale objects. It relates to a preceding article of the journal by the same authors（AMSS, 2013, 26： 9-20） which considered the longitudinal dynamical analysis of a gradient elastic fiber but, in addition to an internal length, an internal time parameter is also introduced to model delay/acceleration effects associated with the underlying microstructure. In particular, the free transverse vibration of a double-walled carbon nanotube（DWNT） is studied by employing gradient elasticity with internal inertia. The inner and outer carbon nanotubes are modeled as two individual elastic beams interacting with each other through van der Waals（vdW） forces. General explicit expressions are derived for the natural frequencies and the associated inner-to-outer tube amplitude ratios for the case of simply supported DWNTs. The effects of internal length（or scale）and internal time（or inertia） on the vibration behavior are evaluated. The results indicate that the internal length and time parameters of the adopted strain gradient-internal inertia generalized elasticity model have little influence on the lower order coaxial and noncoaxial vibration modes,but a significant one on the higher order modes.

关键词： carbon nanotubes gradient elasticity internal inertia vibration behavior

Prediction of particle size and layer-thickness distributions in a continuous horizontal fluidized-bed coating process

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Particuology 2020年第3期18卷 1-12页

作者： P.Bachmann k.Chen A.Buck e.Tsotsas Thermal Process engineering Otto-von-Guericke UniversityUniversit(a)tsplatz 2Magdeburg D-39106Germany Institute of Particle Technology Friedrich-Alexander University Erlangen-NurembergCauerstr.4Erlangen D-91058Germany

To predict the particle size and layer-thickness distributions(LTDs)in a continuously operated horizontal fluidized-bed granulation process,two alternative models were considered.A one-dimensional two-zone model was proposed,which describes with population-balance equations the particle growth in a spraying zone that is separated from the drying *** residence-time distribution(RTD)was calculated from a literature correlation and was coupled with a population-balance model via a tank-in-series model with reflux.A two-dimensional,one-zone population-balance model,which was based directly on the RTD and the feed particle-size distribution(PSD)was also *** experiments were conducted and analyzed microscopically and with a camera optical device to determine the sample *** over the particle population were derived from the PSDs and were analyzed directly by *** compare the simulated data with the experimentally determined distributions,the PSDs were converted to *** good agreement shows that both methods are suitable to determine the PSD from an RTD of an arbitrary granulation process in a horizontal fluidized *** appears necessary with regards to the LTD spread.

关键词： Fluidized bed Continuous process Coating,Residence-time distribution Particle-size distribution Layer-thickness distribution

Zinc-oxide/PDMS-clad tapered fiber saturable absorber for passively mode-locked erbium-doped fiber laser

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Chinese Physics B 2021年第5期30卷 384-389页

作者： F D Muhammad S A S Husin e k Ng k Y Lau C A C Abdullah M A Mahdi Department of Physics Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Wireless and Photonics Networks Research Centre Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of electronics and Nanoengineering Tietotie 3Aalto University02150 EspooFinland

We propose and demonstrate a passively mode-locked erbium-doped fiber laser(eDFL)based on zinc-oxide/polydimethylsiloxane(ZnO/PDMS)saturable absorber(SA)that evanescently interacts with the light on a tapered *** ZnO/PDMS composite is coated on the whole surface of the tapered fiber to guarantee the maximum efficiency of the SA device,with a measured insertion loss of 0.87 dB and a modulation depth of 6.4%.The proposed laser can generate soliton mode-locking operation at a threshold power of 33.07 *** generated output pulse yields a repetition rate and pulse width of 9.77 MHz and 1.03 ps,*** results indicate that the proposed ZnO/PDMS-clad tapered fiber could be useful as an efficient,compatible,and low-cost SA device for ultrafast laser applications.

关键词： zinc-oxide saturable absorber tapered fiber mode-locked fiber laser

DYNAMIC ANALYSIS OF A GRADIeNT eLASTIC POLYMeRIC FIBeR

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Acta Mechanica Solida Sinica 2013年第1期26卷 9-20页

作者： k.Y.Xu k.A.Alnefaie N.H.Abu-Hamdeh k.H.Almitani e.C.Aifantis Department of Mechanics Shanghai University Department of Mechanical engineering King Abdulaziz University Lab of Mechanics and Materials Polytechnic SchoolAristotle University

A dynamic analysis of an elastic gradient-dependent polymeric fiber subjected to a periodic excitation is considered. A nonlinear gradient elasticity constitutive equation with strain- dependent gradient coefficients is first derived and the dispersive wave propagation properties for its linearized counterpart are briefly discussed. For the linearized problem a variational formulation is also developed to obtain related boundary conditions of both classical （standard） and non-classical （gradient） type. Analytical solutions in the form of Fourier series for the fiber＇s displacement and strain fields are provided. The solutions depend on a dimensionless scale parameter （the diameter to length radio d = D/L） and, therefore, size effects are captured.

关键词： gradient elasticity polymeric fibers periodic excitations size effects

Subacute ruminal acidosis in dairy herds:Microbiological and nutritional causes,consequences,and prevention strategies

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Animal Nutrition 2022年第3期10卷 148-155页

作者： Mawda e.elmhadi Darien k.Ali Mawahib k.khogali Hongrong Wang Laboratory of Metabolic Manipulation of Herbivorous Animal Nutrition College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China Department of Veterinary Preventive Medicine and Public Health Faculty of Veterinary MedicineUniversity of KhartoumKhartoum NorthSudan College of Animal Science and Technology Yangzhou UniversityYangzhou225009China

Dairy cattle are frequently fed high-concentrate(HC)diets in modern intensive feeding systems,especially in the transition *** this period,cows face many alterations that include hormonal changes and shifting to a lactating *** to a HC diet that may disrupt the ruminal microbiota balance can lead to subacute ruminal acidosis(SARA).Moreover,the main factor shaping the rumen microbiota is dietary composition,especially the ratio of starch to fibrous *** highly fermentable carbohydrate diets after adaptation to forage diets leads to a rumen fermentation rate that exceeds rumen absorption and buffering rates,resulting in a reduction in ruminal *** a result of Gram-negative bacterial cell lysis,an increase in harmful ruminal bacterial metabolites,including lipopolysaccharide,lactic acid,and histamine,is *** interactions between the host immune system and the ruminal microbiota play an essential role in many physiological processes and the development of the *** in DNA sequencing and bioinformatics platforms provides new opportunities to investigate the composition of ruminal microbes and yields unique advances in understanding ecology of the *** ruminal acidosis is linked with a change in the ruminal microbiota structure and richness and with other metabolic disorders;such as rumenitis,milk fat depression,laminitis,and liver ***,this review aims to explore a better understanding of the crosstalk between diet and microbiota in the prevalence of rumen acidosis and its consequences,which is crucial for control strategies such as feeding management,and supplementation with thiamine,prebiotics,and probiotics.

关键词： Subacute ruminal acidosis High-concentrate diet Microbial diversity Inflammatory and immune response Prevention

Approximate Bound States Solution of the Hellmann Potential

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Communications in Theoretical Physics 2013年第7期60卷 1-8页

作者： M. Hamzavi k.e. Thylwe and A.A. Rajabi Department of Science and engineering Abhar Branch Islamic Azad University kTH-Mechanics Royal Institute of Technology Physics Department Shahrood University of Technology

The Hellmann potential, which is a superposition of an attractive Coulomb potential -air and a Yutmwa potential b e-δr /r , is often used to compute bound-state normalizations and energy levels of neutral atoms. By using the generalized parametric Nikiforov-Uvarov （NU） method, we have obtained the approximate analytical solutions of the radial Schr6dinger equation （Se） for the Hellmann potential. The energy eigenvalues and corresponding eigenfunctions are calculated in closed forms. Some numerical results are presented, which show good agreement with a numerical amplitude phase method and also those previously obtained by other methods. As a particular case, we find the energy levels of the pure Coulomb potential.

关键词： Schrodinger equation Hellmann potential Nikiforov-Uvarov method

Higher-Order Corrections to earth's Ionosphere Shocks

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Communications in Theoretical Physics 2017年第1期67卷 90-96页

作者： H.G.Abdelwahed e.k.el-Shewy Plasma Technology and Material Science Unit(PTMSU) Physics DepartmentCollege of Science and Humanitarian StudiesPrince Sattam bin Abdulaziz UniversityAlkharjKSA Theoretical Physics Group Physics DepartmentFaculty of ScienceMansoura UniversityMansouraEgypt

Nonlinear shock wave structures in unmagnetized collisionless viscous plasmas composed fluid of positive(negative) ions and nonthermally electron distribution are examined. For ion shock formation, a reductive perturbation technique applied to derive Burgers equation for lowest-order potential. As the shock amplitude decreasing or enlarging,its steepness and velocity deviate from Burger equation. Burgers type equation with higher order dissipation must be obtained to avoid this deviation. Solution for the compined two equations has been derived using renormalization analysis. effects of higher-order, positive- negative mass ratio Q, electron nonthermal parameter δ and kinematic viscosities coefficient of positive(negative) ions η1 and η2 on the electrostatic shocks in earth's ionosphere are also argued.

关键词： nonthermal electrons ion shock waves Burgers equation Burger type equation renormalization method higher-order dissipation