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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

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

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

Cracking in orthotropic half-plane with a functionally graded coating under anti-plane loading

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Acta m.chanica Solida Sinica 2015年第2期28卷 210-220页

作者： m. m. m.nfared m. Ayatollahi Faculty of Engineering University of Zanjan

This investigation evaluates, by the dislocation m.thod, the dynam.c stress intensity factors of cracked orthotropic half-plane and functionally graded m.terial coating of a coating- substrate m.terial due to the action of anti-plane traction on the crack surfaces. First, by using the com.lex Fourier transform. the dislocation problem.can be solved and the stress fields are obtained with Cauchy singularity at the location of dislocation. The dislocation solution is utilized to derive integral equations for m.ltiple interacting cracks in the orthotropic half-plane with functionally graded orthotropic coating. Several exam.les are solved and dynam.c stress intensity factors are obtained.

关键词： orthotropic half-plane m.ltiple cracks functionally graded coating

Transport m.chanism.in chem.cally reactive hybrid nanofluid flow containing gyrotactic m.cro-organism. over a curved oscillatory surface

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.Im.AN T.ASGHAR Z.ABBAS Departm.nt of m.them.tics Division of Science and TechnologyUniversity of Education Departm.nt of m.them.tics The Islamia University of Bahawalpur

This paper exam.nes the transport analysis, including both heat transfer and m.ss transfer, in hybrid nanofluid flow containing gyrotactic m.croorganism. towards a curved oscillatory surface. The influence of m.gnetic fields is also inspected in term. of their physical characteristics. To depict the phenom.na of transport, m.dified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and hom.geneous chem.cal reactions are also incorporated. Utilizing a curvilinear coordinate system. the flow problem.is form.lated as partial differential equations(PDEs)for m.m.ntum. concentration, m.croorganism.field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the hom.topy analysis m.thod(HAm..The effects of significant flow param.ters on the pressure and m.croorganism.fields, velocity, oscillation velocity, concentration, and tem.erature distributions are shown via graphs. Furtherm.re, the variations in skin friction, m.ss transfer rate, heat transfer rate, and local m.tile num.er due to different involved param.ters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and tem.erature fields are enhanced as the values of the solid volum. fraction variables *** is also verified that the concentration rate field decreases as the values of the hom.geneous reaction strength param.ter and the radius of curvature param.ter increase, and it increases with the Schm.dt num.er and the heterogeneous reaction strength *** outcom.s show a favorable response of the m.tile num.er to advanced values of the Peclet num.er, the Schm.dt num.er, the m.croorganism.difference param.ter, and the bio-convective Lewis num.er.

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Brain-penetrating neurotrophic factor m.m.tics: HER-096 as a disease-m.difying therapy for Parkinson’s disease

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira m.Holm.tröm.Henri J.Huttunen Herantis Pharm. Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A m.jor unm.t need in the field of central nervous system.diseases is disease-m.difying *** for decades there have been various sym.tom.tic treatm.nts available to alleviate the sym.tom. of the disease,disease-m.dification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatm.nt therapeutic

Dye-sensitized solar cells based on Cr-doped TiO2 nanotube photoanodes

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Rare m.tals 2017年第11期36卷 865-871页

作者： m. m. m.m.ni Departm.nt of Chem.stry Isfahan University of TechnologyIsfahan 84156-83111 Iran

The effect of chrom.um.doping on the photo- voltaic efficiency of dye-sensitized solar cells （DSSCs） with anodized TiO2 nanotubes followed by an annealing process was investigated. Cr-doped TiO2 nanotubes （CrTNs） with different am.unts of chrom.um.were obtained by anodizing of titanium.foils in a single-step process using potassium.chro- m.te as the chrom.um.source. Film.features were investigated by scanning electron m.croscopy （SEm., X-ray diffraction （XRD）, energy-dispersive X-ray spectroscopy （EDX）, and ultraviolet-visible （UV-Vis） spectroscopy. It is clearly seen that highly ordered TiO2 nanotubes are form.d in an anodizing solution free of potassium.chrom.te, and with a gradual increase in the potassium.chrom.te concentration, these nanotube structures change to nanoporous and com.act film. without porosity. The photovoltaic efficiencies of fabricated DSSCs were characterized by a solar cell m.asurem.nt sys- tem.via the photocurrent-voltage （l-V） curves. It is found that the photovoltaic efficiency of DSSCs with CrTNsl sam.le is im.roved by m.re than three tim.s com.ared to that of DSSCs with undoped TNs. The energy conversion efficiency increases from.1.05 % to 3.89 % by doping of chrom.um.

关键词： Dye-sensitized solar cell Photoanodes Nanotubes Anodization

Arctic sea-ice extent: No record m.nim.m.in 2023 or recent years

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Atm.spheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen Environm.ntal and Rem.te Sensing Center BergenNorway

Arctic sea-ice extent reaches its m.nim.m.each year in Septem.er. On 11 Septem.er 2023 the m.nim.m.was 4.969 m.llion square kilom.ters(***^(2)). This was not a record low, which occurred in 2012, when the m.nim.m.was 4.175 ***^(2), 0.794 ***^(2) less than the m.nim.m.in 2023. However, the ice extent had decreased by 0.432 ***^(2) com.ared with 2022. Nevertheless, the sum.er m.lting in 2023 was rem.rkably less than expected when considering the strong heat waves in the atm.sphere and ocean, with record tem.eratures set around the world. In general, there is a high correlation between the long-term.decrease in sea-ice extent and the increasing CO_(2) in the atm.sphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in Septem.er, while the rem.inder is caused by natural variability.

关键词： Sea ice Arctic m.nim.m.ice Clim.te