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convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen P.Nutman clark r.l.Friend Vickie c.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;rollinson,2007;van de löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,Pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with Phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing Plate tectonics Suprasubduction crustal evolution

crABP1-mediated non-canonical retinoic acid signaling in motor neurons and neural stem cells

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Neural regeneration research 2024年第6期19卷 1169-1170页

作者： li-na Wei Department of Pharmacology University of Minnesota Medical SchoolMinneapolisMNUSA

retinoic acid(rA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(corcoran et al.,2002).The effects of rA are mediated by two very distinct pathways;the first is manifested in the nucleus by binding to a large family of nuclear rA receptors(rArs)to regulate proper expression of rAtargeted genes.

关键词： canonical spectrum critical

Public transport inclusion and active aging: A systematic review on elderly mobility

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 312-347页

作者： na Zhang Qi Yang School of Humanities Chang'an UniversityXi'an 710064China School of Transportation Engineering Chang'an UniversityXi'an 710064China School of Economics and Management Chang'an UniversityXi'an 710064China

Global aging has brought attention to addressing the elderly mobility dilemma,and a commitment to address inclusive transport in *** inclusion for older adults aims at establishing an age-friendly transport *** a direct policy goal and promoting active aging as an indirect social goal,to help older populations gain access to transport and social *** on the analysis of scientific knowledge mapping over the past 30 years,this study visualizes the hotspots and trends in elderly mobility *** a qualitative analysis of 138 papers,this paper reviews the theoretical foundations for transport inclusion and three themes of elderly mobility research,proposes a framework for public transport(PT)inclusion research as well as future research *** study suggests that transport inclusion can help enhance elderly health,social participation,and subjective *** can improve their travel opportunities for active aging in four ways:opportunity accessibility,physical accessibility,age-friendly informationalization,and cost *** research should pay attention to examining the mechanism of perceived transport inclusion on active aging,expanding the multilevel research space of the capability approach(cA),and exploring the subjectiveobjective integrated research model for PT *** research contributes to the overall knowledge of the theoretical and empirical researches on PT inclusion for the elderly and promotes the integrated application of interdisciplinary knowledge in the field.

关键词： Transportation engineering Elderly mobility Transport-related social exclusion Transport inclusion Active aging

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

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Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： Si-na Wei Zhao-Qing Feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the lanzhou quantum molecular dynamics transport model(***). Using the ***, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the *** are able to describe the experimental data of STAr collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich ***, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision collective flow Pion production Symmetry energy relativistic mean field

Partial linear Model Averaging Prediction for longitudinal Data

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Journal of Systems Science & complexity 2024年第2期37卷 863-885页

作者： lI na FEI Yu ZHANG Xinyu Faculty of Science Kunming University of Science and TechnologyKunming 650500China School of Statistics and Mathematics Yunnan University of Finance and EconomicsKunming 650221China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

Prediction plays an important role in data *** averaging method generally provides better prediction than using any of its *** though model averaging has been extensively investigated under independent errors,few authors have considered model averaging for semiparametric models with correlated *** this paper,the authors offer an optimal model averaging method to improve the prediction in partially linear model for longitudinal *** model averaging weights are obtained by minimizing criterion,which is an unbiased estimator of the expected in-sample squared error loss plus a *** properties,including asymptotic optimality and consistency of averaging weights,are established under two scenarios:(i)All candidate models are misspecified;(ii)correct models are available in the candidate *** studies and an empirical example show that the promise of the proposed procedure over other competitive methods.

关键词： Asymptotic optimality longitudinal data model averaging estimator partially linear model prediction

A review on nanomaterial-based Strategies for Manipulating Tumor Microenvironment to Enhance chemodynamic Therapy

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chemical research in chinese Universities 2024年第2期40卷 202-212页

作者： cAO Mengyu XING Xiner SHEN Xiaotong OUYANG Jin na na Key laboratory of radiopharmaceuticals Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing100875P.R.China Department of chemistry College of Arts and SciencesBeijing Normal University at ZhuhaiZhuhai519087P.R.China State Key laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430074P.R.China

cancer is a leading cause of death worldwide,and a series of strategies has been reported for tumor-specific ***,chemodynamic therapy(cDT)has become a research hotspot for antitumor treatment due to its advantages of high specificity,endogenous stimulation,and high ***,the therapeutic effects of cDT are normally limited in the complex tumor microenvironment(TME),such as insufficient acidity,tumor hypoxia,low hydrogen peroxide(H2O2),and high glutathione(GSH).consequently,different kinds of multifunctional nanomaterials have been designed to manipulate TME conditions,which provided more opportunities to improve the efficiency of *** review focuses on nanomaterial-based strategies for enhancing cDT through manipulating *** cDT enhancements,this review would provide a reference for the future development of efficient cDT nanomaterials.

关键词： chemodynamic therapy Tumor microenvironment nanomaterial Manipulating strategy Fenton/Fenton-like reaction

A head-mounted photoacoustic fiberscope for hemodynamic imaging in mobile mice

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light(Science & Applications) 2024年第6期13卷 1012-1014页

作者： Xiaoyan Zheng Shuai na national Biomedical Imaging center College of Future TechnologyPeking UniversityBeijing100871China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing100871China

A miniaturized photoacoustic fiberscope has been developed, featuring a lateral resolution of 9 microns and a lightweight design at 4.5 grams. Engineered to capture hemodynamic processes at single-blood-vessel resolution at a rate of 0.2 Hz, this device represents an advancement in head-mounted tools for exploring intricate brain activities in mobile animals.

关键词： fiber mobile Engine

Effect of radiative loss mechanisms on FIr thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.l Silva l.A.O.Nunes S.M.lima l.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIr)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIr parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt rare earths

Microstructure and room temperature fracture toughness of Nb-Si-based alloys with Sr addition

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rare Metals 2024年第8期43卷 3904-3912页

作者： Yong-lin Huang li-na Jia Bin Kong Yue-ling Guo na Wang School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Nb-Si-based alloys show great potential to surpass the widely used Ni-based *** element Sr is widely applied in aluminum and magnesium alloys,but reports about the effects of Sr on Nb-Si-based alloys are quite ***,Nb-Si-based alloys with nominal compositions of Nb-15Si-24Ti-4cr-2Al-2Hf-0/0.05/0.15Sr(at%)were prepared by directional solidification and heat *** microstructural characterization and room temperature fracture toughness of Nb-Si-based alloy were systematically *** show that all these alloys consist of Nb_5Si_3 phase embedded within Nb solid solution(Nb_(ss)) *** Nb_(5)Si_(3) phase becomes refined and more discontinuous after adding minor *** for the fracture toughness,0.05 at% and 0.15 at% Sr additions do not cause significant *** discontinuous and refining mechanism of Sr element was studied,and the analysis of toughness decreasing with Sr addition reveals that the size of Nb_(ss) phase plays a crucial role in determining the fracture toughness.

关键词： Nb-Si alloy refinement Discontinuous Fracture toughness Nb_(ss)