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A study of nonlinear age-structured population m.dels

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International Journal of Biom.them.tics 2016年第6期9卷 211-223页

作者： Syed Tauseef m.hyud-Din A. Waheed m. m. ra.shidi Departm.nt of m.them.tics Faculty of Sciences HITEC University Taxila Cantt Pakistan Departm.nt of m.them.tics COMSATS Institute of Information Technology Attock Pakistan Shanghai Key Lab of Vehicle Aerodynam.csand Vehicle Therm.l m.nagem.nt System. Tongji University 3800 Cao An Road Jiading Shanghai 201803 P. R. China

This paper presents a novel analysis for the solution of nonlinear age-structured prob- lem.which is of extrem. im.ortance in biological sciences. The presented m.del is very useful but quite com.licated. m.dified variational iteration m.thod （m.Im. coupled with auxiliary param.ter is used to cope with the com.lexity of the m.del which subse- quently shows better results as com.ared to som. existing results available in literature. Furtherm.re, an appropriate way is used for the identification of auxiliary param.ter by m.ans of residual function. Num.rical exam.les are presented for the analysis of the pro- posed algorithm. Graphical results along with the discussions re-confirm.the efficiency of proposed algorithm. The work proposes a new algorithm.where He＇s polynom.als and an auxiliary param.ter are m.rged with correction functional. The suggested schem. is im.lem.nted on nonlinear age-structured population m.dels. Graphs are plotted for the residual function that reflects the accuracy and convergence of the presented algorithm.

关键词： Age-structured population m.dels nonlinear problem. m.dified variationaliteration m.thod auxiliary param.ter correction functional.

One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science China(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HraFARIN m. V. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor University Physics Departm.nt Razi University

It has been shown that the negative-norm.states necessarily appear in a covariant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultraviolet and infrared di- vergences have been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achieved through the consideration of the nega- tive-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultraviolet divergence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negative energy states

Structural, elastic and electronic properties for m.2 XC (m.Ti and Cr, X=Ga and Al) phases from.ab initio calculations

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Acta m.tallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. Fatm. N. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids m.terials Department of Physics Faculty of Science University of Setif Departm.nt of Physics University Center Research Unit on Em.rging m.terials Ferhat Abbas University of Setif Departm.nt of Physics Faculty of Sciences King Khalid University Central m.tallurgical Research and Developm.nt Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m.XC phases depending on the type of m.transition m.tal （m.are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are perform.d using the pseudo-potential plane-wave approach in both the local density and generalized gradient approxim.tions. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic param.ters, Debye tem. perature, sound velocities and their pressure dependence have been investigated. In agreem.nt with experim.ntal and previous theoretical findings, it is found that the com.ressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m.elem.nts on the m.chinability indices of the m.terial have been exam.ned. The electronic properties have been discussed in term. of chem.cal bonding showing that bonding is due to m.-Cp and m.-Xp hybridizations. m.C bonds are stiffer than m.X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m.X and m.C bonds increases with increasing the num.er of VEC.

关键词： m.XC phases ab initio Pressure effect Band structures

Enhancem.nt in antinociceptive and anti-inflam.atory effects of tram.dol by transderm.l proniosom. gel

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Asian Journal of Pharm.ceutical Sciences 2020年第6期15卷 786-796页

作者： Jigar Shah Anroop B.Nair hiral Shah Shery Jacob Tam.r m.Shehata m.ham.d Aly m.rsy Institute of Pharm.cy Nirma UniversityAhmedabad 382481India College of Clinical Pharm.cy King Faisal UniversityAl-Ahsa 31982Saudi Arabia Arihant School of Pharm.cy&BRI Gandhinagar 382421India College of Pharm.cy Gulf Medical UniversityAjman 4184United Arab Emirates Faculty of Pharm.cy University of ZagazigZagazig 44519Egypt Faculty of m.dicine Minia UniversityEl-Minia 61511Egypt

Oral therapy of tram.dol,an opiate analgesic,undergoes extensive hepatic m.tabolism.and requires frequent *** therapy by virtue can overcom. these issues and can im.rove the efficacy and reduce abuse liability of *** aim.of this research was to investigate the possibility of transderm.l delivery of tram.dol by form.lating proniosom. gel and evaluate its therapeutic potential in *** effect of form.lation com.osition as well as am.unt of drug on physicochem.cal characteristics of prepared proniosom.s were *** proniosom. gel(F4)was selected and evaluated for drug release,stability and transderm.l efficacy by ex vivo and in vivo *** vesicles dem.nstrated optim.l properties including spherical shape,nanosize with good entrapm.nt efficiency,adequate zeta potential,higher stability and greater transderm.l *** am.rphization and dispersion of tram.dol in the aqueous core of proniosom. vesicles was confirm.d by differential scanning *** profile of F4 was distinct(Pm.control and displayed steady and prolonged tram.dol release by Fickian *** therapy of F4 showed prom.nent reduction of induced twitches(Pm.ce and edem.(Prats,as com.ared to oral *** im.rovem.nt in clinical efficacy of tram.dol in transderm.l therapy is correlated with the pharm.cokinetic data *** conclusion,the observed im.rovem.nt in antinociceptive and anti-inflam.atory effects from.proniosom. carriers signifies its potential to be a suitable alternative to oral therapy of tram.dol with greater efficacy.

关键词： Tram.dol Proniosom.s Flux Edem. Pharm.cokinetics rats

Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.EFTEKHARI Departm.nt of m.chanical Engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

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Neurogenesis dynam.cs in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： m.awiah m.Naffaa Departm.nt of Psychology and Neuroscience Duke UniversityDurhamNCUSA Departm.nt of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons m.grating to the granule cell layer and glom.rular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit rem.deling triggered by m.m.ry and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. m.reover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory inform.tion processing. This adaptive process responds to changes in epithelial com.osition and contributes to the form.tion of olfactory m.m.ries by m.dulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions rem.ins a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around m.tral and tufted cells. This organizational pattern significantly im.acts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and m.m.ry. Additionally, this organization is further shaped by axon term.nals originating from.cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these com.lex and highly interconnected processes have not been com.rehensively studied as a whole. Therefore, this m.nuscript aim. to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These m.chanism. are thought to support olfactory learning and m.m.ry, potentially through increased

关键词： network adaptability neurogenesis neuronal com.unication olfactory bulb olfactory learning olfactory m.m.ry synaptic plasticity

Stellar structure m.del in hydrostatic equilibrium.in the context of f(R)-gravity

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Research in Astronom. and Astrophysics 2017年第12期17卷 31-40页

作者： raíla Andr Gilberto m.Krem.r Departam.nto de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil m.nipal Centre for Natural Sciences Manipal UniversityManipal 576104India

In this work we present a stellar structure m.del from.the f（R）-gravity point of view capable of describing som. classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This m.del is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium.equation and a polytropic equation of state. We com.are the results obtained with those found by Newtonian theory. It has been observed that in these system., where high curvature regim.s em.rge,stellar structure equations undergo m.difications. Despite the sim.licity of this m.del, the results are satisfactory. The estim.ted values of pressure, density and tem.erature of the stars are within those determ.ned by observations. This f（R）-gravity m.del has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosm.logy:theory stars:general m.ssive brown dwarfs white dwarfs neutron

Is there a potential of circulating m.RNAs as biom.rkers in rheum.tic diseases?

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Genes & Diseases 2023年第4期10卷 1263-1278页

作者： Klára Prajzlerová Ladislav Senolt m.ria Filková Institute of Rheum.tology Prague 12800Czech Republic Departm.nt of Rheum.tology First Faculty of MedicineCharles UniversityPrague 12800Czech Republic

t m.croRNAs(m.RNAs)are sm.ll non-coding single-stranded RNAs of about 22 nucle-otides in length that act as post-transcriptional regulators of gene *** on the com.lem.ntarity between m.RNA and target m.NA,cleavage,destabilization,or transla-tional suppression of m.NA occurs within the RISC(RNA-induced silencing com.lex).As gene expression regulators,m.RNAs are involved in a variety of biological *** of m.RNAs and their target genes contribute to the pathophysiology of m.ny diseases,including autoim.une and inflam.atory *** are also present extracellularly in their sta-ble form.in body *** incorporation into m.m.rane vesicles or protein com.lexes with Ago2,HDL,or nucleophosm.n 1 protects them.against ***-free m.RNAs can be deliv-ered to another cell in vitro and m.intain their functional ***,m.RNAs can be considered m.diators of intercellular *** rem.rkable stability of cell-free m.RNAs and their accessibility in body fluid m.kes them.potential diagnostic or prognostic bio-m.rkers and potential therapeutic *** we provide an overview of the potential role of circulating m.RNAs as biom.rkers of disease activity,therapeutic response,or diagnosis in rheum.tic *** circulating m.RNAs reflect their involvem.nt in the pathogenesis,while for plenty,their pathogenetic m.chanism. rem.in to be *** m.RNAs described as biom.rkers were also shown to be of therapeutic potential,and som. m.RNAs arealready tested in clinical trials.

关键词： Biom.rker Diagnosis m.RNA Rheum.tic diseases Therapy

m.tochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflam.aging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología m.lecular Severo Ochoa(CBm. Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” com.s from.the Latin senescens, m.aning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from.stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting