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Statistical Theory and Related Fields 2019年第1期3卷 48-58页

作者： S.A.Komolafe T.o.obilade i.o.ayodeji A.R.Babalola Department of Mathematics Obafemi Awolowo UniversityIle-Ife 220005Nigeria

With a view to providing a tool to accurately model time series processes which may be corrupted with errors such as measurement,round-off and data aggregation,this study developedan integrated moving average(iMA)model with a transition matrix for the errors resulting ina convex combination of two ARMA *** on interest rates in the United States andNigeria were used to demonstrate the application of the formulated *** tools such asthe autocovariance function,maximum likelihood method,Newton–Raphson iterative methodand Kolmogorov–Smirnov test statistic were employed to examine and fit the formulated specification to *** results showed that the proposed model provided a generalisation and amore flexible specification than the existing models of AR error and ARMA error in fitting timeseries processes in the presence of errors.

关键词： Structural relationship measurement error correlated errors autocovariance function

Creation of an oxygen-enriched environment during synthesis as an effective way to improve luminescent properties of Y_(2)o_(3):Eu^(3+)

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Journal of Rare Earths 2025年第1期43卷 21-29,I0001页

作者： Aleksandr A.Nashivochnikov Anton i.Kostyukov Mariana i.Rakhmanova Lidiya S.Kibis Svetlana V.Cherepanova Evgenii A.Suprun Novosibirsk State University Pirogova Str.2630090NovosibirskRussia Boreskov institute of Catalysis SB RAS 5 Lavrentiev Ave630090NovosibirskRussia Nikolaev institute of inorganic Chemistry SB RAS 3 Lavrentiev Ave630090NovosibirskRussia

The growing demand for luminescent nanomaterials intended for various applications increases the necessity to develop and improve approaches to the creation of highly efficient nanosized *** current study,an approach to enhancing the efficiency of red luminescence of monoclinic Y_(2)o_(3):Eu^(3+)with the particle size of~20 nm by creating the oxygen-enriched environment during the gas-phase synthesis was *** investigate the effect of oxygen amount during the synthesis on characteristics of the phosphor,a series of nano structured Y_(2)o_(3):Eu^(3+)with the addition of 0-40 vol%o_(2) to the main buffer gas Ar was synthesized by laser *** is shown that the amount of added o_(2) exerts virtually no effect on the phase composition and particle size,but significantly improves the luminescent characteristics of Y_(2)o_(3):Eu^(3+).Thus,the addition of 30 vol%o_(2) leads to virtually a 20-fold growth in the photoluminescence(PL)intensity caused by ^(5)D_(0)→^(7)F_(0-4) transitions in Eu^(3+)and an increase in the absolute PL quantum yield from 3%to 53%(λex=395 nm)compared to the sample synthesized without o_(2).The addition of oxygen also improves the emission color coordinates from(0.571,0.320)to(0.630,0.322)due to the removal of a considerable fraction of oxygen *** synthesized nanopowders are shown to be highly stable:upon storage under ambient conditions for two *** yield(QY)of the samples decreases by less than 2%.it is expected that the key features underlying the proposed approach will be useful for various methods used to synthesize oxide nanophosphors.

关键词： Photoluminescence Quantum yield Laservaporization Y_(2)0_(3):Eu^(3+) Monoclinic Y_(2)0_(3) Rareearths

Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based Medical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i Međo ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča institute of Nuclear Sci-ences-National institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： H.HoSSEiNi o.BALiLASHAKi Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. it is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. in addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： cylindrical cavity o353.4 point source porous medium stress concentration wave-field transformation

Blood biomarkers of Alzheimer’s disease:important considerations for use in clinical practice

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Neural Regeneration Research 2025年第1期20卷 205-206页

作者： Sarah Fullam Sean o’Dowd Antoinette o’Connor Department of Neurology Tallaght University HospitalDublinIreland Academic Unit of Neurology Trinity College DublinIreland

introduction:Fluid and positron emission tomography(PET)biomarkers that enable the detection of the hallmark proteins of Alzheimer’s disease(AD)(amyloid and tau)have revolutionized our approach to the diagnosis of *** evolution of AD diagnostic criteria to include biological characterization(Alzheimer’s Association Working Group,2023)provides an appropriate framework to reduce levels of clinico-pathologic mismatch and improve in-vivo diagnostic *** the therapeutic landscape for neurodegenerative disease evolves,it is increasingly incumbent on clinicians to provide timely,and pathologically precise diagnoses for ***,the expensive and invasive nature of these tests limits their scalability.

关键词： Blood Alzheimer diagnosis

insights into transferal to fractal space modeling:delayed forced Helmholtz-Duffing oscillator with the non-perturbative approach

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Communications in Theoretical Physics 2025年第1期77卷 11-22页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The damped Helmholtz-Duffing oscillator is a topic of great interest in many different fields of study due to its complex *** transitioning from conventional continuous differential equations to their fractal counterparts,one gains insights into the system's response under new mathematical *** paper presents a novel method for converting standard continuous differential equations into their fractal *** conversion occurs after the nonlinear system is transformed into its linear *** analyses show that there are several resonance sites in the fractal system,which differ from the one resonance point found in the continuous *** important finding is that the fractal system loses some of its stabilizing power when decaying behavior is transformed into a diffuse ***,a decrease in the fractal order in resonance settings shows a stabilizing impact,highlighting the dynamics'complexity inside fractal *** endeavor to convert to fractals is a revolutionary technique that is being employed for the first time.

关键词： nonlinear oscillations Helmholtz-Duffing oscillator forced with delay effect non-perturbative methodology stability outlines new perspectives on transferal to fractal space modeling

Modeling net-charge fluctuations in heavy-ion collisions at the LHC

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Chinese Physics C 2025年第1期49卷 281-289页

作者： G.o.Ambaryan A.S.Chernyshov G.Kh.Eyyubova V.L.Korotkikh i.P.Lokhtin S.V.Petrushanko A.M.Snigirev E.E.Zabrodin Physics Department Lomonosov Moscow State UniversityRU-119991 MoscowRussia Skobeltsyn institute of Nuclear Physics Lomonosov Moscow State UniversityRU-119991 MoscowRussia Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear ResearchRU-141980 DubnaRussia Department of Physics University of OsloN-0316 OsloNorway

Analysis of Pb+Pb data for net-charge fluctuations at LHC energies using the HYDJET++model is *** strongly intensive quantities D and Σ were used to remove the effects related to system volume *** employed two versions of HYDJET++for the *** first one is the standard or default version,whereas the second one is a modification that takes into account explicit event-by-event conservation of the electric net-charge of produced *** inclusion of the canonical net-charge conservation in the model allows for better description of the experimental data obtained by the ALiCE and CMS Collaborations.A comparison with calculations from other models is also presented.

关键词： relativistic heavy-ion collisions net-charge fluctuations strongly intensive variables canonical charge conservation

Vegetation dynamics at the southern edge of the Siberian mountain taiga

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Journal of Mountain Science 2025年第2期22卷 451-465页

作者： iM Sergei T KHARUK Viacheslav i PETRoV il'ya A SHUSHPANoV Alexander S DViNSKAYA Maria L oNDAR Sergei o V.N.Sukachev institute of Forest Krasnoyarsk Science Centre of the Siberian Branch of Russian Academy of ScienceKrasnoyarsk 660036Russia institute of Ecology and Geography Institute of Space and Information TechnologiesSiberian Federal UniversityKrasnoyarsk 660041Russia Laboratory of Biodiversity and Ecology Tomsk State UniversityTomsk 634050Russia institute of Space Research and High Technologies Reshetnev Siberian State University of Science and TechnologyKrasnoyarsk 660014Russia Department of Biology and Ecology Tuvan State UniversityKyzyl 667000Russia

The growth,survival,and mortality of conifer species in response to the hydrothermal regime have received considerable *** is expected that the highest sensitivity of trees to the warming-drying climate will occur mainly at the edges of the species *** focused on the responses to climate change of the drought-resistant larch(Larix sibirica)and the moisture-sensitive Siberian pine(Pinus sibirica)along the elevation gradient in the Tannu-ola Ridge,the southern margin where those two species coexist in Siberia by using satellite data(MoDiS,Landsat,and microwave),the indexes of gross(GPP)and net(NPP)primary productivity,and tree radial growth index(Gi).We found that since the warming restart in the 2000s,the area of larch-dominated forests increased by~150%while the area of pine-dominated forests decreased by~10%.The Siberian pine has retreated at low elevations(increased its area at higher *** contrast,the area of larch stands increased in both the uphill and downhill ***(Betula spp.)also increased its area at low elevations(about+120%).Since 2001,the forested area increased by~5%.A shrubification,i.e.,an increase in the area of shrubs,was observed at high *** uphill rate of timberline and shrubline migration was about 0.3 m/*** the 2000s,vegetation NPP has increased by 13%.A notable correlation between NPP and the Gi of larch and pine was found(r=0.5-0.7).At lower elevations,NPP positively correlated with precipitation and soil moisture,while air temperature and VPD(vapor pressure deficit)increase inhibited *** high elevations,the effects of these variables on productivity *** continuous decline of the Siberian pine forest indicates an inevitable retreat of this species at low elevations and its replacement by larch and birch.

关键词： Trees range changes Mountain taiga Siberian larch Siberian pine Timberline Shrubification Tree uphill migration Forest population dynamics Ecological resilience Habitat suitability

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

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher J.o’Connell Matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBi)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBis are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic