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Interacting tachyonic scalar field

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Communications in Theoretical Physics 2021年第2期73卷 102-107页

作者： A Kundu s d Pathak V K Ojha department of Physies Lovely Professional UniversityPhagwaraPunjab144411India school of sciences SAGE University BhopalMadhya Pradesh462022India

We discuss the coupling between dark energy and matter by considering a homogeneous tachyonic scalar field as a candidate for dark *** obtained the functional form of scale factor by assuming that the coupling strength depends linearly on the Hubble parameter and energy *** also estimated the cosmic age of the Universe for different values of coupling constant.

关键词： dark energy dark matter scalar field achyonic scalar field

Optical theorem,crossing property,and derivative dispersion relations:implications on the asymptotic behavior of σ_(tot)(s) and ρ(s)

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Chinese Physics C 2022年第8期46卷 72-90页

作者： s.d.Campos V.A.Okorokov Applied Mathematics Laboratory-CCTs/dFQM Federal University of São CarlosSorocaba CEP 18052-780Brazil Moscow Engineering Physics Institute National Research Nuclear University MEPhI115409 MoscowRussia

In this paper,we present some results on the behavior of the total cross section and p-parameter at asymptotic energies in proton-proton(pp) and antiproton-proton(pp) ***,we consider three of the main theoretical results in high energy physics:the crossing property,derivative dispersion relation,and optical *** use of such machinery facilitates the derivation of analytic formulas for a wide set of the measured global scattering parameters and some important relations between *** suggested parameterizations approximate the energy dependence for the total cross section and ρ-parameter for pp and pp with a statistically acceptable quality in the multi-TeV ***,the qualitative description is obtained for important interrelations,namely difference,sum,and ratio of the antiparticle-particle and particle-particle total cross *** the reduced number of experimental data for the total cross section and p-parameter at the TeV-scale,which complicates any prediction for the beginning of the asymptotic domain,the fitting procedures indicates that asymptotia occur in the energy range 25.5-130 ***,in the asymptotic regime,we obtain α_(P)=1.A detailed quantitative study of the energy behavior of the measured scattering parameters and their combinations in the ultra-high energy domain indicates that the scenario with the generalized formulation of the Pomeranchuk theorem is more favorable with respect to the original formulation of this theorem.

关键词： optical theorem derivative dispersion relations asymptotic behavior Pomeranchuk theorem

The sharma-Tasso-Olver-Burgers equation:its conservation laws and kink solitons

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Communications in Theoretical Physics 2022年第2期74卷 1-8页

作者： K Hosseini A Akbulut d Baleanu s salahshour department of Mathematics Near East University TRNCMersin 10Turkey department of Mathematics-Computer Art-Science FacultyEskisehir Osmangazi UniversityEskisehirTurkey department of Mathematics Faculty of Arts and SciencesCankaya UniversityAnkara 06530Turkey Institute of space sciences Magurele-BucharestRomania Faculty of Engineering and Natural sciences Bahcesehir UniversityIstanbulTurkey

The present paper deals with the sharma-Tasso-Olver-Burgers equation(sTOBE)and its conservation laws and kink *** precisely,the formal Lagrangian,Lie symmetries,and adjoint equations of the sTOBE are firstly constructed to retrieve its conservation *** solitons of the sTOBE are then extracted through adopting a series of newly well-designed approaches such as Kudryashov and exponential *** graphs in 2 and 3d postures are formally portrayed to reveal the dynamical features of kink *** to the authors’knowledge,the outcomes of the current investigation are new and have been listed for the first time.

关键词： sharma-Tasso-Olver-Burgers equation conservation laws Kudryashov and exponential methods kink solitons dynamical features

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 574-586页

作者： Olivier Kerdiles Méryl-Farelle Oye Mintsa Mi-mba Katherine Coulombe Cyntia Tremblay VincentÉmond Martine saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon Facultéde pharmacie UniversitéLaval1050 Avenue de la MédecineQuebecQCCanada Axe Neuroscience Centre de recherche du CHU de Québec-UniversitéLaval(Pavillon CHUL)2705 Boulevard LaurierQuebecQCCanada Institute of Nutrition and Functional Foods QuebecQCCanada Optinutribrain International Associated Laboratory(NutriNeuro FranceINAFCanada)QuebecQCCanada Axe Endocrinologie et Néphrologie Centre de recherche du CHU de Québec-UniversitéLavalQuebecQCCanada département de Médecine Facultéde MédecineUniversitéLavalQuebecQCCanada département de Psychiatrie et Neurosciences Facultéde MédecineQuebecQCCanada

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after *** that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic ***,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal *** weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 *** this period,the animals had access to a running wheel,which they could use or *** acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars ***,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned *** to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal dOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned *** present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

关键词： 6-hydroxydopamine dopamine dopamine transporter exercise neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3

Charge self-trapping in two strand biomolecules:Adiabatic polaron approach

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Chinese Physics B 2023年第1期32卷 253-263页

作者： d Chevizovich s Zdravković A V Chizhov Z Ivić University of Belgrade Vinča Institute of Nuclear SciencesP.O.Box 522Belgrade 11001Serbia Joint Institute for Nuclear Research Laboratory for Radiation BiologyDubna 141980Russia dubna state University Dubna 141980Russia department of Physics University of CreteP.O.Box 2208Heraklion 71003Greece National University of science and Technology MIsis Leninsky prosp.4Moscow 119049Russia

We investigate the properties of the excess charge(electron, hole) introduced into a two-strand biomolecule. We consider the possibility that the stable soliton excitation can be formed due to interaction of excess charge with the phonon subsystem. The influence of overlap of the molecular orbitals between adjacent structure elements of the macromolecular chain on the soliton properties is discussed. special attention is paid to the influence of the overlapping of the molecular orbitals between structure elements placed on the different chains. Using the literature values of the basic energy parameters of the two-chain biomolecular structures, possible types of soliton solutions are discussed.

关键词： charge self-trapping adiabatic polaron soliton two-stranded biomolecules

Polyethylene glycol fusion repair of severed sciatic nerves accelerates recovery of nociceptive sensory perceptions in male and female rats of different strains

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Neural Regeneration Research 2025年第9期20卷 2667-2681页

作者： Liwen Zhou Karthik Venkudusamy Emily A.Hibbard Yessenia Montoya Alexa Olivarez Cathy Z.Yang Adelaide Leung Varun Gokhale Guhan Periyasamy Zeal Pathak dale R.sengelaub George d.Bittner department of Neuroscience University of TexasAustinTXUSA Program in Neuroscience Indiana UniversityBloomingtonINUSA department of Molecular Biosciences University of TexasAustinTXUSA

successful polyethylene glycol fusion(PEG-fusion)of severed axons following peripheral nerve injuries for PEG-fused axons has been reported to:(1)rapidly restore electrophysiological continuity;(2)prevent distal Wallerian degeneration and maintain their myelin sheaths;(3)promote primarily motor,voluntary behavioral recoveries as assessed by the sciatic Functional Index;and,(4)rapidly produce correct and incorrect connections in many possible combinations that produce rapid and extensive recovery of functional peripheral nervous system/central nervous system connections and reflex(e.g.,toe twitch)or voluntary *** preceding companion paper describes sensory terminal field reo rganization following PEG-fusion repair of sciatic nerve transections or ablations;howeve r,sensory behavioral recovery has not been explicitly explored following PEG-fusion *** the current study,we confirmed the success of PEG-fusion surgeries according to criteria(1-3)above and more extensively investigated whether PEG-fusion enhanced mechanical nociceptive recovery following sciatic transection in male and female outbred sprague-dawley and inbred Lewis *** nociceptive responses were assessed by measuring withdrawal thresholds using von Frey filaments on the dorsal and midplantar regions of the *** von Frey filament tests were a more reliable method than plantar von Frey filament tests to assess mechanical nociceptive sensitivity following sciatic nerve *** withdrawal thresholds of the sciatic-mediated lateral dorsal region differed significantly across strain but not *** thresholds did not change significantly from baseline in chronic Unoperated and sham-operated *** sciatic transection,all rats exhibited severe hyposensitivity to stimuli at the lateral dorsal region of the hindpaw ipsilateral to the ***,PEG-fused rats exhibited significantly earlier return to baseline withdrawal thresholds than Negative

关键词： autophagia axotomy collateral sprouting neuropathic pain peripheral nerve repair polyethylene glycol fusion(PEG-fusion) saphenous nerve sensory neurons sex and strain Wallerian degeneration

Effects of bottom shear stresses on the wave-induced dynamic response in a porous seabed:PORO-WssI (shear) model

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Acta Mechanica sinica 2011年第6期27卷 898-910页

作者： J.Ye d.-s.Jeng division of Civil Engineering University of Dundee Center for Marine Geotechnical Engineering State Key Laboratory of Ocean EngineeringShanghai Jiao Tong University

When ocean waves propagate over the sea floor,dynamic wave pressures and bottom shear stresses exert on the surface of *** bottom shear stresses provide a horizontal loading in the wave-seabed interaction system,while dynamic wave pressures provide a vertical loading in the ***,the bottom shear stresses have been ignored in most previous studies in the *** this study,the effects of the bottom shear stresses on the dynamic response in a seabed of finite thickness under wave loading will be examined,based on Biot＇s dynamic poro-elastic *** the model,an ＂u-p＂ approximation will be adopted instead of quasi-static model that have been used in most previous *** results indicate that the bottom shear stresses has certain influences on the wave-induced seabed dynamic ***,wave and soil characteristics have considerable influences on the relative difference of seabed response between the previous model（without shear stresses） and the present model（with shear stresses）.As shown in the parametric study,the relative differences between two models could up to 10% of p0,depending on the amplitude of bottom shear stresses.

关键词： Bottom shear stresses Wave-induced dynamicresponse Porous seabed - "u-p" approximation - Biot's the-ory

Finite deformation analysis of crack tip fields in plastically compressible hardening–softening–hardening solids

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Acta Mechanica sinica 2017年第1期33卷 148-158页

作者： d.Khan s.singh A.Needleman Mechanical Engineering department Indian Institute of Technology Banaras Hindu University department of Materials science & Engineering Texas A&M University College Station

Crack tip fields are calculated under plane strain small scale yielding conditions. The material is characterized by a finite strain elastic-viscoplastic constitutive relation with various hardening-softening-hardening hardness functions. Both plastically compressible and plastically incompressible solids are considered. displacements corresponding to the isotropic linear elastic mode I crack field are prescribed on a remote boundary. The initial crack is taken to be a semi-circular notch and symmetry about the crack plane is imposed. Plastic compressibility is found to give an increased crack opening displacement for a given value of the applied loading. The plastic zone size and shape are found to depend on the plastic compressibility, but not much on whether material softening occurs near the crack tip. On the other hand, the near crack tip stress and deformation fields depend sensitively on whether or not material softening occurs. The combination of plastic compressibility and softening (or softening-hardening) has a particularly strong effect on the near crack tip stress and deformation fields.

关键词： Plasticity Crack tip fields Fracture Compressible solids Material softening

Notch severity Effect on Hydrogen Embrittlement of Type 4340 steel

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Journal of Materials science & Technology 1996年第1期12卷 51-56页

作者： Liu, s Zhu, ZY Ke, W Hardie, d UNIV NEWCAsTLE UPON TYNE DEPT MECH MAT & MFG ENGNNEWCASTLE TYNE TE1 7RUTYNE & WEARENGLAND

Hydrogen embrittlement of Type 4340 steel has been investigated by straining round-notched specimens in 10(5) Pa hydrogen atmosphere at a constent cross-head spead of 1.4x10(-4) mm/s. The circumferentially notched specimens exhibited a significant embrittlement when their mechanical behaviour in hydrogen was compared with that in air. Although the effect of notch depth on fracture strength in air is negligible, an increase in the depth of notch increase susceptibility to embrittlement when testing in gaseous hydrogen. However, analysis of the effects is complicated by the facts that (i) the specimens show some degree of notch severity even when strained in air and (ii) the behaviour is complicated by the localised plastic deformation that may occur for relatively shallow notches. such effects are eliminated at high stress concentration factors, so there is a systematic loss in fracture stress in hydrogen as the notch sensitivity increases from K-t=2.6 to 5.7 (where a 87% reduction of fracture stress occurs) but a relatively stable value is then reached even for very severe notching by fatigue pre-cracking. Whether or not the effect is due to increasing concentration of hydrogen in the triaxial stress region ahead of the notch, there is no doubt that increasing the stress concentration makes hydrogen more effective as an embrittlement agent.

关键词： Carbon steel