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Estimation of radiative capture^(13)b(n,γ0+1)^(14)b reaction rate in the modified potential cluster model

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Chinese Physics C 2023年第10期47卷 130-142页

作者： A.s.Tkachenko N.A.burkova b.M.Yeleusheva s.b.dubovichenko Fesenkov Astrophysical Institute 050020AlmatyKazakhstan al-Farabi Kazakh National University 050040AlmatyKazakhstan

We discuss current attempts to employ the modified potential cluster model to describe the available experimental data on the^(13)b(n,γ0+1)^(14)b total *** estimated results of the M1 and E1 transitions from the n^(13)b scattering states to the ground and first excited states of^(14)b are *** 1st resonance at Ex=1.275 MeV(1+)is revealed in both the cross-section and reaction *** the variation in the asymptotic constant,a thermal cross-section interval of 5.1-8.9 mb is *** on the theoretical total cross-sections at energies of 0.01 eV to 5 MeV,we calculate the reaction rate in the temperature range of 0.01 to *** ignition T9 values of the^(13)b(n,γ0+1)^(14)b reaction depending on a neutron number density n_(n)of~10^(22)cm^(−3)are *** radiative neutron capture reaction rates on the boron^(10-13)b and carbon^(12-14)Сisotopes are compared.

关键词： radiative neutron capture ^(14)b nucleus total cross-sections reaction rate potential cluster model r-process

Astrophysical s-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： s.b.dubovichenko A.s.Tkachenko R.Ya.Kezerashvili N.A.burkova b.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate school and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)s_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 *** calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances is elucidated.A comparison of our calculation for the s-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances in reference to the CNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle

Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato socodato João b.Relvas Institute of Research and Innovation in Health(i3s)and Institute for Molecular and Cell biology(IbMC) University of PortoPortoPortugal Department of biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNs)and the immune *** exploration is particularly significant in understanding microglia,the CNs’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-borràs Marta balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase b receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated Trkb/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorb

Nonsmooth semi-Infinite Minmax Programming Involving Generalized(Φ, ρ)-Invexity

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Journal of systems science & Complexity 2015年第4期28卷 857-875页

作者： UPADHYAY b b MIsHRA s K Department of basic sciences & Humanities National Institute of Technology

This paper introduces some new generalizations of the concept of （~, p）-invexity for non- differentiable locally Lipschitz functions using the tools of Clarke subdifferential. These functions are used to derive the necessary and sufficient optimality conditions for a class of nonsmooth semi-infinite minmax programming problems, where set of restrictions are indexed in a compact set. Utilizing the sufficient optimality conditions, the authors formulate three types of dual models and establish weak and strong duality results. The results of the paper extend and unify naturally some earlier results from the literature.

关键词： Duality, generalized invexity locally Lipschitz functions, minmax programming, semi-infinite programming.

A comprehensive approach to an equation of state for hard spheres and Lennard Jones fluids

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Chinese Physics b 2011年第8期20卷 271-278页

作者： s.b.Khasare 90 New Jagruti Colony Katol Road NagpurIndia

We present a simple method of obtaining various equations of state for hard sphere fluid in a simple unifying way. We will guess equations of state by using suitable axiomatic functional forms （n = 1, 2, 3, 4, 5） for surface tension sn （r）, r≥ d/2 with intermolecular separation r as a variable, where m is an arbitrary real number （pole）. Among the equations of state obtained in this way are Percus-Yevick, scaled particle theory and Carnahan-starling equations of state. In addition, we have found a simple equation of state for the hard sphere fluid in the region that represents the simulation data accurately. It is found that for both hard sphere fluids as well as Lennard-Jones fluids, with m = 3/4 the derived equation of state （EOs） gives results which are in good agreement with computer simulation results. Furthermore, this equation of state gives the Percus-Yevick （pressure） EOs for the m = 0, the Carnahan-starling EOs for rn = 4/5, while for the value of m = 1 it corresponds to a scaled particle theory EOs.

关键词： equation of state Lennard-Jones potential hard-sphere potential computer algebra,computer simulation

Thermodynamic study of fluid in terms of equation of state containing physical parameters

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Chinese Physics b 2015年第1期24卷 382-387页

作者： s.b.Khasare Department of Physics science College Congress Nagar Nagpur Maharashtra State India

We introduce a simple condition for one mole fluid by considering the thermodynamics of molecules pointing towards the effective potential for the cluster. Efforts are made to estimate new physical parameter f in liquid state using the equation of state containing only two physical parameters such as the hard sphere diameter and binding energy. The temperature dependence of the structural properties and the thermodynamic behavior of the clusters are studied. Computations based on f predict the variation of numbers of particles at the contact point of the molecular cavity（radial distribution function）.From the thermodynamic profile of the fluid, the model results are discussed in terms of the cavity due to the closed surface along with suitable energy. The present calculation is based upon the sample thermodynamic data for n-hexanol, such as the ultrasonic wave, density, volume expansion coefficient, and ratio of specific heat in the liquid state, and it is consistent with the thermodynamic relations containing physical parameters such as size and energy. since the data is restricted to n-hexanol, we avoid giving the physical meaning of f, which is the key parameter studied in the present work.

关键词： equations of state Lenard–Jones potential hard-sphere potential

Negative refractions by triangular lattice sonic crystals in partial band gaps

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Chinese Physics b 2015年第4期24卷 310-321页

作者： s.Alagoz b.b.Alagoz A.sahin s.Nur Department of Physics Inonu University Department of Electrical and Electronics Engineering Inonu University Vocational school of Health services Medical Imaging Techniques Inonu University

This study numerically demonstrates the effects of partial band gaps on the negative refraction properties of sonic crystal. The partial band gap appearing at the second band edge leads to the efficient transmissions of scattered wave envelopes in the transverse directions inside triangular lattice sonic crystal, and therefore enhances the refraction property of sonic crystal. Numerical simulation results indicate a diagonal guidance of coupled scattered wave envelopes inside crystal structure at the partial band gap frequencies and then output waves are restored in the vicinity of the output interface of sonic crystal by combining phase coherent scattered waves according to Huygens＇ principles. This mechanism leads to two operations for wavefront engineering： one is spatial wavefront shifting operation and the other is convex-concave wavefront inversion operation. The effects of this mechanism on the negative refraction and wave focalization are investigated by using the finite difference time domain （FDTD） simulations. This study contributes to a better understanding of negative refraction and wave focusing mechanisms at the band edge frequencies, and shows the applications of the slab comer beam splitting and sC-air multilayer acoustic system.

关键词： sonic crystal negative refraction wave focusing partial band gap

Perturbation and variational approach for the equation of state for hard-sphere and Lennard-Jones fluids

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Chinese Physics b 2012年第4期21卷 383-395页

作者： s. b. Khasare Department of Physics Science College Congress Nagar Nagpur India

The present work uses the concept of a scaled particle along with the perturbation and variation approach, to develop an equation of state （EOs） for a mixture of hard sphere （Hs）, Lennar-Jones （L J） fluids. A suitable flexible functional form for the radial distribution function G（R） is assumed for the mixture, with R as a variable. The function G（R） has an arbitrary parameter m and a different equation of state can be obtained with a suitable choice of m. For m = 0.75 and m = 0.83 results are close to molecular dynamics （MD） result for pure Hs and LJ fluid respectively.

关键词： equation of state Lennard-Jones potential hard-sphere potential liquid mixture com- puter simulation