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Communications in Theoretical Physics 2005年第5X期44卷 891-896页

作者： g.r. Boroun Physics Department Razi University Kermanshah 67149 Iran

An approximate analytical form of the gluon distribution function from the derivative F2 proton structure function data at low-x assuming the regge-like behavior of the gluon distribution function at this limit is presented. In this method, we calculate λ and C parameters for each low-x value at several Q^2 values using the scaling violation of the F2 proton structure function. For low-x, A is found to be independent of x within the experimental accuracy. We make use of the leading order Altarelli-Parisi （A-P） evolution equations in our analysis. To test the validity of our new determined gluon distribution functions, we compare them with the QCD parton distribution functions at low-x region.

关键词： regge-like behavior DgLAP equation for gluon low x

Analysis of the Longitudinal Structure Function F_L from the Non-linear regge gluon Density Behavior at Low-x

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Chinese Physics Letters 2015年第11期32卷 18-21页

作者： BOrOUN g.r. rEZAEI B. Physics Department Razi University

The longitudinal structure function with shadowing correction according to the nonlinear effects of the gluon density behavior at low x is considered. The solution of the g.r.MQ evolution equation for the gluon density shows that the FL^g（x, Q2） behavior can be tamed by the singularity at low x values. Comparing our results with H1 data at r=4 geV-1 shows that at very low x this behavior is completely tamed by taking shadowing correction into account.

关键词： Analysis of the Longitudinal Structure Function F_L from the Non-linear regge gluon Density Behavior at Low-x

Calculation of the Longitudinal Structure Function from regge-Like Behaviour of the gluon Distribution Function in Leading Order Approximation at Low x

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Chinese Physics Letters 2007年第5期24卷 1187-1190页

作者： g.r. Boroun B. rezaie Department of Physics Razi University Kermanshah 67149 Iran

We present the calculations of FL longitudinal structure functions from DgLAP evolution equation in leading order （LO） at low-x, assuming the regge-like behaviour of gluon distribution at this limit. The calculated results are compared with the H1 data and QCD fit. It is shown that the obtained results are very close to the mentioned methods. The proposed simple analytical relation for EL provides a t-evolution equation for the determination of the longitudinal structure function at low-x. All the results can consistently be described within the framework of perturbative QCD, which essentially shows increases as x decreases.

关键词： PrOTON

Longitudinal Structure Function FL from Charm Structure Function F2^c

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Communications in Theoretical Physics 2013年第4期59卷 462-466页

作者： B. rezaei g.r. Boroun Physics Department Razi University

We predict the effect of the charm structure function on the longitudinal structure function at small x. In NLO analysis we find that the hard Pomeron behavior gives a good description of FL and Fk^c （k = 2, L） at small x values. We conclude that a direct relation between FL∝ F2^c would provide useful information on how to measure longitudinal structure function at high 0,2 values. Having checked that this model gives a good description of the data, when compared with other models.

关键词： charm structure function gluon distribution quantum chromodynamics small-x

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam M.r.groh Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton g.r.Wayne Moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Computational Identification of mirNAs and Their Target genes from Expressed Sequence Tags of Tea(Camellia sinensis)

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genomics, Proteomics & Bioinformatics 2010年第2期8卷 113-121页

作者： g.r. Prabu A.K.A. Mandal UPASI Tea research Foundation Department of Biotechnology Karpagam University Plant Biotechnology Division School of Bio Sciences and Technology (SBST)VIT University

MicrorNAs （mirNAs） are a newly identified class of small non-protein-coding post-transcriptional regulatory rNA in both plants and animals. The use of computational homology based search for expressed sequence tags （ESTs） with the Ambros empirical formula and other structural feature criteria filter is a suitable combination towards the discovery and isolation of conserved mirNAs from tea and other plant species whose genomes are not yet sequenced. In the present study, we blasted the database of tea （Camellia sinensis） ESTs to search for potential mirNAs, using previously known plant mirNAs. For the first time, four candidate mirNAs from four families were identified in tea. Using the newly identified mirNA sequences, a total of 30 potential target genes were identified for 11 mirNA families; 6 of these predicted target genes encode transcription factors （20%）, 16 target genes appear to play roles in diverse physiological processes （53%） and 8 target genes have hypothetical or unknown functions （27%）. These findings considerably broaden the scope of understanding the functions of mirNA in tea.

关键词： Camellia sinensis EST mirNA tea

Study on thermal stability of poled non-linear optical polymers

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Chinese Journal of Chemistry 1996年第5期14卷 472-480页

作者： Mhlmann g.r. vanderVorst C.P.J.M. AKZO NOBEL research Laboratories Arnhem P.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe Netherlands

A log.r.thmic expression is proposed to describe relaxation of the polar order in side chain polymers, together with a new way of plotting temperature dependent relaxation data. This results in a straight line extending even below the glass transition temperature in the case of poled nonlinear optics (NLO) side chain polymers. A simple procedure to determine the rotational diffusion constant D-r is given and D-r values of several polymer systems have been evaluated and compared with each other. It appears that, starting from the conventional and well known poled polymer system currently applied, a further lowering of D-r by about 3 orders of magnitude is necessary in order to reach an acceptable orientational stability or lifetime of poled polymers for practical applications. Attempts have been made to introduce electron push-pull substituents into high thermostable molecular frameworks and results of preliminary measurements are reported.

关键词： thermal stability poled polymer film organic nonlinear optical materials

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction trigg.r.ng,and the post-failure large deformation behaviour is essential for designing.r.silient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A stagg.r.d discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction trigg.r.ng and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

NMr double resonance study of azide binding to cytochrome c

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Chinese Journal of Chemistry 1992年第1期10卷 40-44页

作者： CONCAr D. MOOrE g.r. WILLIAMS r.J.P. Inorganic Chemistry Laboratory University of OxfordUK

Equilibrium constants for the binding of azide to ferri-cytochrome c at temperature range of 305—325 K were determined at pH=7 by using ~1H double resonance *** values(⊿H^o=-34.5 kJ/mol,⊿S^o=-100 J/mol)were obtained from van't Hoff's relation and were compared with those for azide binding to other ferric *** reason of lower affinity of cytochrome c for azide was discussed.

关键词： NMr double resonance study of azide binding to cytochrome c