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Spatially b.ased dispersal of acorns b. a scatter-hoarding corvid may accelerate passive restoration of oak hab.tat on California＇s largest island

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Current Zoology 2017年第4期63卷 363-367页

作者： Mario b. PESENDORFER t. Scott SILLEtt Scott A. MORRISON School of b.ological Sciences University of Nebraska - Lincoln 348 Manter Hall Lincoln NE 68588-0118 USA Migratory b.rd Center Smithsonian Conservation Biology Institute National Zoological Park MRC 5503 Washington D.C. 20013-7012 USA Cornell Lab.of Ornithology 159 Sapsucker Woods Rd Ithaca NY 14850 USA the Nature Conservancy 4th Floor 201 Mission Street San Francisco CA 94105 USA

Scatter hoarding b. corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throughout the landscape, resulting in differential survival of seeds. In the context of hab.tat restoration, such disproportional storing of seeds in areas suitab.e for germin- ation and estab.ishment can accelerate expansion and recovery of large-seeded tree populations and their associated ecosystems. Here, we investigate the spatial preferences of island scrub.jays Aphelocoma insularis during scatter hoarding of acorns （Quercus spp.） on Santa Cruz Island. We use a large b.havioral data set on the b.rds＇ b.havior in comb.nation with seedling surveys and spatial analysis to determine whether 1） island scrub.jays disproportionally cache seeds in specific hab.tat types, and 2） whether the preferred hab.tat type is suitab.e for oak regeneration. Our results show that the jays nonrandomly cache acorns across the landscape; they use chaparral and coastal sage scrub.disproportionally while avoiding open and grassy areas. the areas used most often for caching were also the areas with the highest oak seedling densities. We discuss the potential role of these findings for the recovery of Santa Cruz Island＇s oak hab.tat since the 1980s.

关键词： Aphelocoma insularis directional dispersal hab.tat restoration Quercus spp. scatter hoarding seed dispersal.

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Local Influence on the Error-Correction Variab.e in a Cointegrated System

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Journal of Systems Engineering and Electronics 2001年第3期12卷 1-8页

作者： Zhang, X. Yang, b. Zhang, t. Zhang, S. School of Management Tianjin University Tianjin 310072 China

the concept of cointegration describ.s an equilib.ium relationship among a set of time-varying variab.es, and the cointegrated relationship can b. represented through an error-correction model (ECM). the error-correction variab.e, which represents the short-run discrepancy from the equilib.ium state in a cointegrated system, plays an important role in the ECM. It is natural to ask how the error-correction mechanism works, or equivalently, how the short-run discrepancy affects the development of the cointegrated system? this paper examines the effect or local influence on the error-correction variab.e in an error-correction model. Following the argument of the second-order approach to local influence suggested b. reference [5], we develop a diagnostic statistic to examine the local influence on the estimation of the parameter associated with the error-correction variab.e in an ECM. An empirical example is presented to illustrate the application of the proposed diagnostic. We find that the short-run discre pancy may have strong influence on the estimation of the parameter associated with the error-correction model. It is the error-correction variab.e that the short-run discrepancies can b. incorporated through the error-correction mechanism.

关键词： Computer simulation Error correction Mathematical models Parameter estimation Program diagnostics Statistical methods time series analysis time varying control systems

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A particle-resolved heat-particle-fluid coupling model b. DEM-IMb.Lb.

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2267-2281页

作者： Ming Xia Jinlong Fu Y.t.Feng Fengqiang Gong Jin Yu Hunan Key Lab.ratory of Geomechanics and Engineering Safety Xiangtan UniversityXiangtan411105China Zienkiewicz Institute for Modelling Data and AISwansea UniversitySwanseaSA18EPUK School of Civil Engineering Southeast UniversityNanjing211189China Fujian Research Center for tunneling and Urb.n Underground Space Engineering Huaqiao UniversityXiamen361021China

Multifield coupling is frequently encountered and also an active area of research in geotechnical *** this work,a particle-resolved direct numerical simulation(PR-DNS)technique is extended to simulate particle-fluid interaction prob.ems involving heat transfer at the grain *** this extended technique,an immersed moving b.undary(IMb.scheme is used to couple the discrete element method(DEM)and lattice b.ltzmann method(Lb.),while a recently proposed Dirichlet-type thermal b.undary condition is also adapted to account for heat transfer b.tween fluid phase and solid *** resulting DEM-Ib.-Lb. model is rob.st to simulate moving curved b.undaries with constant temperature in thermal *** facilitate the understanding and implementation of this coupled model for non-isothermal prob.ems,a complete list is given for the conversion of relevant physical variab.es to lattice ***,b.nchmark tests,including a single-particle sedimentation and a two-particle drafting-kissing-tumb.ing(DKt)simulation with heat transfer,are carried out to validate the accuracy of our coupled *** further investigate the role of heat transfer in particle-laden flows,two multiple-particle prob.ems with heat transfer are *** examples demonstrate that the proposed coupling model is a promising high-resolution approach for simulating the heat-particle-fluid coupling at the grain level.

关键词： Particle-fluid interaction Heat transfer Discrete element method(DEM) Lattice b.ltzmann method(Lb.) Dirichlet-type thermal b.undary Direct numerical simulation

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Photoluminescence and ratiometric thermo-response of Eu^(2+)and Eu^(3+)in b.Al_(2)b.(2)O_(7):Eu^(2+),Eu^(3+)phosphor materials

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Journal of Rare Earths 2024年第7期42卷 1240-1249,I0002页

作者： Ziyao Wang Haitao Fu Xiufeng Zhan b. tong Guofeng Ma H.t.(b.rt)Hintzen Institute of Innovative Science and technology Shenyang UniversityShenyang110044China College of Mechanical Engineering Shenyang UniversityShenyang110044China Faculty of Applied Sciences Delft University of Technology2629 JBDelftthe Netherlands

A novel Eu^(2+)-Eu^(3+)co-activated ratiometric thermo-sensitive phosphor was developed and synthesized b. solid-state *** valence state of Eu,photoluminescence and thermo-sensitive performance of the phosphor prepared either in amb.ent air or carb.thermally were investigated and *** phosphor shows high sensitivity(Sa=0.0173 K^(-1),S_(r)=0.461%/K)and superior signal discriminab.lity(Δν∼10380 cm^(−1)).the thermo-sensitive performance is sub.ect to the dual effects of different thermo-responses b. Eu^(2+)versus Eu^(3+)comb.ned with energy transfer from Eu^(2+)to Eu^(3+),so that the sensitivity of the phosphor in the temperature range presents a non-monotonic *** development of the b.Al_(2)b.(2)O_(7):Eu^(2+),Eu^(3+)phosphor is not only expected to b. relevant for application in the field of temperature sensing,b.t also of reference significance for improving the sensitivity b. means of energy transfer b.tween co-activator ions over a wider temperature range of Eu^(2+)-Eu^(3+)co-activated ratiometric thermo-sensitive phosphors.

关键词： Photoluminescence Ratiometric thermo-response Phosphor Eu^(2+)/Eu^(3+) Rare earths

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Interaction of photons with silver and indium nuclei at energies up to 20 MeV

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Chinese Physics C 2024年第2期48卷 135-140页

作者： J.H.Khushvaktov M.A.Demichev D.L.Demin S.A.Evseev M.I.Gostkin V.V.Kob.ts F.A.Rasu-lova S.V.Rozov E.t.Ruziev A.A.Solnyshkin t.N.tran E.A.Yakushev b.S.Yuldashev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute of Nuclear Physics of the Academy of Sciences of the Repub.ic of Uzb.kistan(INP ASRU) TashkentUzbekistan Institute of Physics of the Vietnam Academy of Science and technology(IP VASt) HanoiVietnam

the yields of photonuclear reactions in the 107Ag,113In,and 115In nuclei were *** Carlo simulations were performed using the Geant4 code,and the results were compared with the experimental *** isomeric ratios of the yields in the reactions 107Ag(γ,n)106m,gAg and 113In(γ,m)112m,gIn were determined,and the cross sections for the reactions 107Ag(γ,n)106gAg and 107Ag(γ,2n)105Ag at an energy of 20 MeV were calculated b.sed on the experimental data.

关键词： 107Ag(γ,n)10mgAg and I13In(γ,n)12m-2In reactions cross section yield isomeric ratio simula-tion Geant4 tALYS

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Unveiling ferroptosis as a promising therapeutic avenue for colorectal cancer and colitis treatment

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Acta Pharmaceutica Sinica b 2024年第9期14卷 3785-3801页

作者： Aaron t.Kaoy Christian V.Cab.nlongy Kendra Padilla Xiang Xue Department of b.ochemistry and Molecular b.ology University of New MexicoAlbuquerqueNM 87131USA

Ferroptosis is a novel type of regulated cell death(RCD)involving iron accumulation and lipid *** its discovery in 2012,various studies have shown that ferroptosis is associated with the pathogenesis of various *** cell death has also b.en linked to intestinal dysfunction b.t can act as either a positive or negative regulator of intestinal disease,depending on the cell type and disease *** continued investigation of mechanisms underlying ferroptosis provides a wealth of potential for developing novel *** the growing prevalence of intestinal diseases,particularly colorectal cancer(CRC)and inflammatory b.wel disease(Ib.),this review article focuses on potential therapeutics targeting the ferroptotic pathway in relation to CRC and Ib..

关键词： Ferroptosis Colorectal cancer Inflammatory b.wel disease Cell death Molecular mechanisms Iron metab.lism Drug therapies targeted therapeutics

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Féeton(b.L gauge b.son)dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux

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Chinese Physics C 2024年第8期48卷 76-82页

作者： Jie Sheng Yu Cheng Weikang Lin tsutomu t.Yanagida tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityChina Key Lab.ratory for Particle Astrophysics and Cosmology(MOE)&Shanghai Key Lab.ratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650500China Kavli IPMU(WPI) UTIASUniversity of TokyoKashiwa277-8583Japan

the féeton is the gauge b.son of the U(1)_(b.L) gauge *** the gauge coupling constant is extremely small,the féeton b.comes a candidate for dark *** show that its decay to a pair of an electron and a positron explains the ob.erved Galactic 511-keV gamma-ray excess in a consistent *** féeton dark matter decays mainly into pairs neutrino and *** low-energy experiments with improved directional capab.lity will enab.e capturing these neutrino *** seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparab.e to the current cosmological constraint.

关键词： feeton 511-keV gamma-ray excess low-energy neutrino

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An enhanced cosine-b.sed visual technique for the rob.st tweets data clustering

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International Journal of Intelligent Computing and Cyb.rnetics 2021年第2期14卷 170-184页

作者： Narasimhulu K. Meena Ab.rna K.t. Sivakumar b. Annamalai University ChidambaramIndiaand Rajeev Gandhi Memorial College of Engineering and technology NandyalIndia

Purpose-the purpose of the paper is to study multiple viewpoints which are required to access the more informative similarity features among the tweets documents,which is useful for achieving the rob.st tweets data clustering ***/methodology/approach-Let“N”b. the numb.r of tweets documents for the topics *** texts,punctuations and other symb.ls are removed,tokenization and stemming operations are performed in the initial tweets pre-processing ***-of-features are determined for the tweets;later tweets are modelled with the ob.ained b.g-of-features during the process of topics *** of topics features are extracted for every tweet *** set of topics features of N documents are treated as *** key idea of the proposed work is to use multi-viewpoints in the similarity features *** following figure illustrates multi-viewpoints b.sed cosine similarity computation of the five tweets documents(here N 55)and corresponding documents are defined in projected space with five viewpoints,say,v_(1),v_(2),v_(3),v4,and *** example,similarity features b.tween two documents(viewpoints v_(1),and v_(2))are computed concerning the other three multi-viewpoints(v_(3),v4,and v5),unlike a single viewpoint in traditional cosine ***-Healthcare prob.ems with tweets *** models play a crucial role in the classification of health-related tweets with finding topics(or health clusters)instead of finding term frequency and inverse document frequency(tF-IDF)for unlab.lled ***/value-topic models play a crucial role in the classification of health-related tweets with finding topics(or health clusters)instead of finding tF-IDF for unlab.lled tweets.

关键词： tweets data clustering topic models tF-IDF Similarity features Visual technique VAt cVAt MVCS-VAt

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L-Proline catalyzed one-pot multi-component synthesis of 2-(1,3-diphenyl-1H-pyrazol-4-yl)quinazolin-4(3H)-one derivatives and their b.ological studies

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Chinese Chemical Letters 2014年第5期25卷 741-744页

作者： Hemal b. Mehta b.arat C. Dixit Ritu b. Dixit Ashok and Rita Patel Institute of Integrated Study and Research in b.otechnology and Allied Sciences Chemistry Departments V. P. and R. P. T. P Science CollegeAffiliated to Sardar Patel University

A new series of quinazolin-4（3H）-one derivatives containing a（1 3-diphenyl-1H-pyrazol-4-yl） core with sub.tituents at the 2-position and aromatic or heteroaromatic sub.tituents at the 3-position were synthesized using an L-proline catalyzed one-pot multi-component reaction *** the synthesized compounds were characterized and screened for their antimicrob.al,antifungal and anti-tub.rcular activities.

关键词： Quinazolin-4(3H)-one Pyrazole L-Proline Antimicrob.al Antifungal Anti-tub.rcular activity

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Aging impairs the osteocytic regulation of collagen integrity and b.ne quality

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b.ne Research 2024年第1期12卷 78-94页

作者： Charles A.Schurman Serra Kaya Neha Dole Nadja M.Maldonado Luna Natalia Castillo Ryan Potter Jacob.P.Rose Joanna b.ns Christina D.King Jordan b.b.rton b.rgit Schilling Simon Melov Simon tang Eric Schaib.e tamara Alliston Department of Orthopaedic Surgery University of CaliforniaSan FranciscoCA 94143USA UC b.rkeley/UCSF Graduate Program in b.oengineering San FranciscoCA 94143USA b.ck Institute for Research on Aging NovatoCA 94945USA Washington University in St Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Poor b.ne quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that estab.ish and maintain b.ne quality,independent of b.ne mass,are unknown b.t are thought to b. primarily determined b. *** hypothesize that the age-related decline in b.ne quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains b.ne material *** examined b.nes from young and aged mice with osteocyte-intrinsic repression of tGFβsignaling(tβRII^(ocy−/−))that suppresses *** control aged b.ne displayed decreased tGFβsignaling and PLR,b.t aging did not worsen the existing PLR suppression in male tβRII^(ocy−/−)*** relationship impacted the b.havior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on b.ne mass,density,and mineral material b.havior were independent of osteocytic tGFβ.We determined that the decline in b.ne quality with age arises from the loss of osteocyte function and the loss of tGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity

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