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Communications in Theoretical Physics 2018年第3期69卷 241-256页

作者： i.A.Assi A.d.Alhaidari h.Bahlouli department of Physics and Physical Oceanography Memorial University of Newfoundland St. John's NL A1B3XT Canada Saudi Center for Theoretical Physics P.O. Box 32741 Jeddah 21438 Saudi Arabia Physics department King Fahd University of Petroleum & Minerals Dhahran 31261 Saudi Arabia

The aim of this work is to find exact solutions of the dirac equation in(1+1) space-time beyond the already known *** consider exact spin(and pseudo-spin) symmetric dirac equations where the scalar potential is equal to plus(and minus) the vector *** also include pseudo-scalar potentials in the *** spinor wavefunction is written as a bounded sum in a complete set of square integrable basis,which is chosen such that the matrix representation of the dirac wave operator is tridiagonal and *** makes the matrix wave equation a symmetric three-term recursion relation for the expansion coefficients of the *** solve the recursion relation exactly in terms of orthogonal polynomials and obtain the state functions and corresponding relativistic energy spectrum and phase shift.

关键词： dirac equation spin and pseudo-spin tridiagonal representations recursion relation orthogonal polynomials

Recoil polarimetry in meson photoproduction at MAMi

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Chinese Physics C 2009年第12期33卷 1373-1376页

作者： M.h. Sikora d.i. Glazier d.P. Watts University of Edinburgh King’s Buildings Edinburgh EH9 3JZ United Kingdom

The nucleon excitation spectrum remains poorly known, with the masses, widths, EM couplings and even existence of many states not well established. A program of experiments using meson photoproduction off the nucleon is being carried out to improve this situation. A new large acceptance recoil polarimeter has been developed by the Edinburgh group for use in such reactions with the Crystal Ball at MAMi. This work summarizes the procedure used to measure recoil polarization with the new device and presents some preliminary results for the double polarization observable Cx in the reaction γp→pπ, compared to the current partial wave analysis.

关键词： polarimeter meson photoproduction polarization observable recoil

Electron-phonon coupling and spin fluctuations in the ising superconductor NbSe_(2)

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npj Computational Materials 2023年第1期9卷 1686-1694页

作者： S.das h.Paudyal E.R.Margine d.F.Agterberg i.i.Mazin department of Physics and Astronomy George Mason UniversityFairfaxVA 22030USA Quantum Science and Engineering Center George Mason UniversityFairfaxVA 22030USA department of Physics Applied Physicsand AstronomyBinghamton University-SUNYBinghamtonNY 13902USA department of Physics University of WisconsinMilwaukeeWI 53201USA

ising superconductivity,observed in NbSe2 and similar materials,has generated tremendous ***,attention was called to the possible role that spin fluctuations(SF)play in this phenomenon,in addition to the dominant electron–phonon coupling(EPC);the possibility of a predominantly triplet state was discussed and led to a conjecture of viable singlet–triplet Leggett ***,these hypotheses have not been put to a quantitative *** this paper,we report first principle calculations of the EPC and also estimate coupling with SF,including full momentum *** find that:(1)EPC is strongly anisotropic,largely coming from the K-K0 scattering,and therefore excludes triplet symmetry even as an excited state;(2)superconductivity is substantially weakened by SF,but anisotropy remains as above;and,(3)we do find the possibility of a Leggett mode,not in a singlet–triplet but in an s_(++)–s_(±)channel.

关键词： coupling phonon superconductivity

Thermoluminescence Responses of Photon and Electron irradiated Ge- and Al-doped SiO_(2) Optical Fibres

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Chinese Physics Letters 2012年第2期29卷 208-210页

作者： h.Wagiran i.hossain d.Bradley A.N.h.Yaakob T.Ramli department of Physics Universiti Teknologi Malaysia81310 SkudaiJohor Darul TakzimMalaysia department of Physics University of SurreyGuildfordGU27XHUK

We carry out a comparison of the thermoluminescence (TL) response of photon and electron irradiated Ge- and Al-doped SiO_(2) optical fibres,as well as cross-comparison with that of *** is made with 6 MeV electrons and 6 MV photons,for doses ranging from 0.2 Gy to *** commercially available Al- and Gedoped optical fibres produce a linear dose-TL *** TL yield for both of the doped fibres and also for TLd-100 is greater for electron irradiation than for photon *** TL yield of the Al-doped fibres is a small fraction of that of Ge-doped fibres (by a factor of 25),the Ge-doped fibres offering a response of 59%o of that of TLd-100.

关键词： irradiation Electron irradiated

does mesenchymal stem cell’s secretome affect spinal sensory circuits?implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri h.Juárez Adalberto Merighi department of Veterinary Sciences University of TurinGrugliascoTOItaly department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Machine Learning-Based Predictions on the Self-heating Characteristics of Nanocomposites with hybrid Fillers

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Computers, Materials & Continua 2022年第6期71卷 4487-4502页

作者： Taegeon Kil d.i.Jang h.N.Yoon Beomjoo Yang department of Civil and Environmental Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon34141Korea School of Civil Engineering Chungbuk National UniversityCheongju28644Korea

A machine learning-based prediction of the self-heating characteristics and the negative temperature coefficient(NTC)effect detection of nanocomposites incorporating carbon nanotube(CNT)and carbon fiber(CF)is *** CNT content was fixed at 4.0 wt.%,and CFs having three different lengths(0.1,3 and 6 mm)at dosage of 1.0 wt.%were added to fabricate the *** self-heating properties of the specimens were evaluated via self-heating *** on the experiment results,two types of artificial neural network(ANN)models were constructed to predict the surface temperature and electrical resistance,and to detect a severe NTC *** present predictions were compared with experimental values to verify the applicability of the proposed ANN *** ANN model for data prediction was able to predict the surface temperature and electrical resistance closely,with corresponding R-squared value of 0.91 and 0.97,*** ANN model for data detection could detect the severe NTC effect occurred in the nanocomposites under the self-heating condition,as evidenced by the accuracy and sensitivity values exceeding 0.7 in all criteria.

关键词： Machine learning nanocomposites carbon fillers self-heating negative temperature coefficient

CORROSiON ANd MEChANiCAL PROPERTiES OF Ti_3Al-Nb-Mo COMPOSiTES FOR BiO-ANd ENViRONMENTAL MATERiALS PREMREd BY SELF-PROMGATiNG hiGh TEMPERATURE REACTiON

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 149-153页

作者： Y.Choi N.i.Baik h.d.Cho S.i.hong department of Metallurgical and Materials Engineering Sunmoon University#100 Kalsan-RiTangjeoung-MyunAsanChungnam336-840Korea department of Environmental Engineering Sunmoon University#100 Kalsan-RiTangjeoung-MyunAsanChungnam336-840Korea department of Metallurgical Engineering Chungnam National UniversityDaejeon305-764Korea Manuscript received 31 July 2001

Ti3 AL-Nb-Mo composites were prepared by ShS using initial powder mixtures of Ti-Al-Nb-Mo and their corrosion and mechanical properties were studied to develop bioand environmental materials. The composites reached 99.8% of theoretical density after the direct consolidation. The composites shows equiaxed primary a2 in a matrix of fine secondary a2 plates and ordered 82 (Bo) forming a basket weave structure. The strain rate sensitivity (m = dlnσ/dlne) at 2% strain is 0.008. Corrosion potential and corrosion rate of the composites formed by ShS were -151. 5m VShE and 5. 72× 10^(-8)A/cm2 for Ti3 Al-10Nb-1. 5Mo and - 138.4m VShE and 4. 12×10^(-8)cm2 for Ti3 Al-12Nb-1.5Mo in a 50% NaOh-10%FeCi3 solution, respectively. Corrosion resistance decreased with niobium content in the composites and chloride content in the aqueous solution. Selective corrosion of a2 phase in a matrix occurred in the corrosion environment which suggests that the corrosion potential and rate changes are related to the niobium content and Q2 phase in a matrix.

关键词： Ti3 Al alloy corrosion strength ShS

Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

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Neural Regeneration Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen department of Radiology University of MichiganAnn ArborMIUSA department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia department of health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Foundation Research Center of Excellence University of MichiganAnn ArborMIUSA department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging *** and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory *** mechanisms which underpin the integration of these multisensory signals are the principal topic of the present *** multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older *** emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

关键词： aging balance encephalography functional magnetic resonance imaging gait multisensory integration Parkinson’s disease positron emission tomography somatosensory vestibular visual

Self-phase modulation via similariton solutions of the perturbed NLSE Modulation instability and induced self-steepening

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Communications in Theoretical Physics 2022年第8期74卷 41-50页

作者： h i Abdel-Gawad department of Mathematics Faculty of Science Cairo University Egypt

The perturbed nonlinear Schrodinger equation(PNLSE)describes the pulse propagation in optical fibers,which results from the interaction of the higher-order dispersion effect,self-steepening(SS)and self-phase modulation(SPM).The challenge between these aforementioned phenomena may lead to a dominant one among *** is worth noticing that the study of modulation instability(Mi)leads to the inspection of dominant phenomena(dPh).indeed,the Mi triggers when the coefficient of dPh exceeds a critical value and it may occur that the interaction leads to wave *** PNLSE is currently studied in the literature,mainly on finding traveling wave ***,we are concerned with analyzing the similarity solutions of the *** exact solutions are obtained via introducing similarity transformations and by using the extended unified *** solutions are evaluated numerically and they are shown *** is observed that the intensity of the pulses exhibits self steepening which progresses to shock soliton in ultrashort time(or near t=0).Also,it is found that the real part of the solution exhibits self-phase modulation in *** study of(Mi)determines the critical value for the coefficients of SS,SPM,or high dispersivity to occur.

关键词： Perturbed NLSE steepening self–phase modulation extended unified method

Unsteady time-dependent incompressible Newtonian fluid flow between two parallel plates by homotopy analysis method(hAM),homotopy perturbation method(hPM)and collocation method(CM)

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Propulsion and Power Research 2018年第3期7卷 247-256页

作者： M.R.Shirkhani h.A.hoshyar i.Rahimipetroudi h.Akhavan d.d.Ganji department of Mechanical Engineering Sari BranchIslamic Azad UniversitySariIran Young Researchers Club Sari BranchIslamic Azad UniversitySariIran department of Mechanical Engineering Ghaemshahr BranchIslamic Azad UniversityGhaemshahrIran

Analytical and numerical analyses have performed to study the problem of the flow of incompressible Newtonian fluid between two parallel plates approaching or receding from each other *** Navier–Stokes equations have been transformed into an ordinary differential equation using a similarity *** powerful analytical methods called collocation method(CM),the homotopy perturbation method(hPM),and the homotopy analysis method(hAM)have been used to solve nonlinear differential *** has been attempted to show the capabilities and wide-range applications of the proposed methods in comparison with a type of numerical analysis as fourth-order Runge–Kutta numerical method in solving this ***,velocity fields have been computed and shown graphically for various values of physical *** objective of the present work is to investigate the effect of Reynolds number and suction or injection characteristic parameter on the velocity field.

关键词： homotopy analysis method(hAM) Collocation method(CM) homotopy perturbation method(hPM) Parallel porous plates Unsteady flow