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Reconstruction method in <i>F(G)</i>Gravity: stability study and Inflationary survey

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journal of modern Physics 2021年第6期12卷 781-797页

作者： C. A&iuml namon m. j. s. houndjo A. A. L. Ayivi m. G. Ganiou A. Kanfon Institut de mathématiques et de sciences Physiques (ImsP) Porto-Novo Bénin Faculté des sciences et Techniques de Natitingou Natitingou Bénin Département de Physique Université d’Abomey-Calavi Calavi Bénin

The present paper is devoted to reconstruction and cosmological study in modified F(G) theory of gravity. Our reconstruction scheme is based on Friedmann metric induced equations in modified F(G) theory by supposing a... 详细信息

The present paper is devoted to reconstruction and cosmological study in modified m>F(G)m> theory of gravity. Our reconstruction scheme is based on Friedmann metric induced equations in modified m style="white-space:normal;">F(G)m> theory by supposing a power law form for the scale factor of Friedmann metric. Firstly, we deal with the stability study, the obtained model. This survey reveals that for appropriated choice of the reconstructed model parameter, this model is stable under two cosmological evolutions namely the de sitter and the power law evolutions symbolized by the appropriated scale factor. secondly, we investigate the inflationary survey by fitting the model with the inflation observables. These observables are determined and their comparison with Planck’s results leads to a special inflationary m style="white-space:normal;">F(G)m> model. We prove that this model especially obtained for radiation domination evolution develops an instability, so can fall to ordinary matter domination era or dark energy domination era. This is the key of graceful exit from inflation.

关键词： modified Gravity Inflation stability Gauss-Bonnet

Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

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Neural Regeneration Research 2025年第10期20卷 2913-2914页

作者： William j.Flerlage mark L.Dell’Acqua Brian m.Cox Fereshteh s.Nugent Uniformed services University of the Health sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

Brain-penetrating neurotrophic factor mimetics: HER-096 as a disease-modifying therapy for Parkinson’s disease

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira m.Holmström Henri j.Huttunen Herantis Pharma Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying *** for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatment therapeutic

sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi sun shiqian shen Robert j.Thomas m.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Use of silica nanopowder to accelerate CO_2 sorption by Ca(OH)_2

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Particuology 2013年第4期11卷 448-453页

作者： m.A.s.Quintanilla j.m.Valverde Faculty of Physics University of SevilleAvenida Reina Mercedes s/n

Promising technologies have recently emerged to capture CO2 from postcombustion flue gas and to enhance the production of hydrogen from natural gas by steam-methane reforming, on the basis of sorp- tion of CO2 by Ca-based powders. The rate of CO2 sorption on Ca-based powders is limited by both carbonation kinetics and transport of CO2 to unreacted sorption sites. Ca-based powders may exhibit cohesive aggregation, thus hindering gas-solids contact efficiency. In our work, we tested the sorption rate of powder samples prepared by dry mixing of a cohesive Ca（OH）2 powder with a silica nanopowder used as additive. The silica nanopowder serves to improve the dispersibility of Ca（OH）2. Consequently, when a CO2 enriched gas and the modified sorbent are brought into contact, the rate of CO2 sorption is enhanced in the initial fast phase of interest for practical applications.

关键词： FluidizationFine powdersCO2 sorptionNanoparticles

Cross-focusing of two chirped Gaussian laser beams and THz wave generation in plasmas of multi-ion species under a weakly relativistic and ponderomotive regime

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Plasma science and Technology 2022年第10期24卷 1-11页

作者： m R jAFARI mILANI s REZAEI m j jAFARI Photonics and Quantum Technologies Research school Nuclear Science and Technology Research InstituteTehran 14665-678Iran Plasma and Fusion Research school Nuclear Science and Technology Research InstituteTehran 14399-51113Iran

The generation of terahertz(THz)waves via the beating of two high-intensity chirped Gaussian lasers in a multi-ion-species plasma is numerically studied by taking into account the weak relativistic and ponderomotive regime of *** coupled differential equations for beamwidth parameters are extracted by introducing the dielectric function of such plasma and using WKB and paraxial ray *** amplitude of THz radiation at beat frequency resulting from the nonlinear current density induced by the beat ponderomotive force of the cross-focusing of beams was *** impacts of the chirp frequency parameter,initial laser intensity and initial ionic species density(specifically,the presence of singly and doubly charged ions)in the plasma on THz generation were *** numerical results reveal that THz radiation generation strongly depends on the chirp frequency parameter.A specific range of chirp frequencies exists for self-focusing as well as THz generation with a'turning point',where the THz emission reaches its maximum *** results show that the strength of self-focusing and consequently the generated THz radiation are reduced by increasing the density of doubly charged ionic species in the plasma due to the suppression of the nonlinear effects.

关键词： laser–plasma interaction THz generation chirped Gaussian laser beams

solution of shallow-water equations using least-squares finite-element method

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Acta mechanica sinica 2008年第5期24卷 523-532页

作者： s.j. Liang j,-H, Tang m.-s. Wu Department of marine Environmental Informatics National Taiwan Ocean UniversityKeelung 20224 Taiwan China Department of Bioenvironmental Engineering Chung-Yuan Christian University Chung-Li 32023 Taiwan China Department of Geographic Information systems Feng Chia University Taichung 40724 Taiwan China

A least-squares finite-element method （LsFEm） for the non-conservative shallow-water equations is presented. The model is capable of handling complex topography, steady and unsteady flows, subcritical and supercritical flows, and flows with smooth and sharp gradient changes. Advantages of the model include：（1） sources terms, such as the bottom slope, surface stresses and bed frictions, can be treated easily without any special treatment; （2） upwind scheme is no needed; （3） a single approximating space can be used for all variables, and its choice of approximating space is not subject to the Ladyzhenskaya-Babuska-Brezzi （LBB） condition; and （4） the resulting system of equations is symmetric and positive-definite （sPD） which can be solved efficiently with the preconditioned conjugate gradient method. The model is verified with flow over a bump, tide induced flow, and dam-break. Computed results are compared with analytic solutions or other numerical results, and show the model is conservative and accurate. The model is then used to simulate flow past a circular cylinder. Important flow charac-teristics, such as variation of water surface around the cylinder and vortex shedding behind the cylinder are investigated. Computed results compare well with experiment data and other numerical results.

关键词： Least-square finite-element method,shallow-water equations Dam-break Vortex shedding

Health risk of whole body vibration in mining trucks during various operational conditions

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journal of Central south University 2017年第8期24卷 1808-1816页

作者： Rahimdel m.j mirzaei m sattarvand j Hoseinie s.H Department of mining Engineering Sahand University of TechnologyTabriz ***Iran Department of mechanical Engineering Sahand University of TechnologyTabriz ***Iran Department of mining Engineering Isfahan University of TechnologyIsfahan ***Iran

mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the IsO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(Rms) of vertical vibrations. However, the effect of the payload is not considerable on the Rms. moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.

关键词： mining trucks operational conditions health risk whole body vibration

Particle size Distribution and Characterization of High siliceous and microporous materials

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journal of materials science & Technology 2005年第4期21卷 563-570页

作者： s.KDurrani j.Akhtar m.Ahmad m.j.moughal Nuclear materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamabad PakistanNuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamabad PakistanNuclear Physics Divisions Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamaad PakistanNuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore. Islamabad. Pakistan

Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate （sAPO） microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer （PsA） and scanning electron microscope （sEm）. The PsA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. student t-test and variance ratio test （F-test） methods were performed for the significance of results by the analysis of variance （ANONA） and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett ＆ Teller （BET） volumetric technique and v-αs plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials.

关键词： synthesis High siliceous zeolites microporous materials Particle size distribution micropore volume sEm