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Susceptibility of pine stands to bark stripping by chacma baboons Papio ursinus in the Eastern Highlands of Zimbabwe

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current Zoology 2009年第6期55卷 389-395页

作者： c.a.t.katsvanga L.JIMU J.F.MUPANGWA D.ZINNER Department of Environmental Science Bindura University of Science Education Faculty of Agriculture Umutara Polytechnic Department of cognitive Ethology German Primate Center(DPZ)

the aim of this study was to determine the susceptibility, intensity and distribution of pine trees to bark stripping by chacma baboons Papio ursinus in three plantations in the Eastern Highlands of Zimbabwe. the number of plots/ha, stripped trees/ plot and stripped trees/ha was recorded during the pre-rainy, rainy and post-rainy seasons from August 2006 to May 2007. During data collection, altitude, aspect, season and other site predictor variables （e. g., roads and fire traces, water points, indigenous vegetation conservation areas, crop felds, human settlements, wattle scrubs, rocky areas, open grasslands, earlier stripped sites and roost sites） were recorded for each plot in association with selected predictor variables within plantation estates. Data on the number of stripped plots/ha, stripped trees/plot and stripped trees/ha were analysed as dependent variables using the Generalised Linear Model （GLM） through SPSS version 15 （2006） to determine which predictor variables were significantly related to bark stripping. Differences between means were tested using Bonferroni tests with a 5 % level of significance. Our findings show that bark stripping of pine trees by baboons occurred at all altitudes and aspects. Overall, the number of bark stripped trees/ha did not significandy vary by season. the number of bark stripped plots/ha was lower during the pre-rainy season than the rainy season, whereas the number of bark stripped trees/plot was higher during the pre-rainy than the rainy season. Bark stripping of pines occurred more often in the vicinities of areas with abundant food and water

关键词： chaema baboons Papio ursinus Altitude Aspect Bark stripped plots Predictor variables Seasonality

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津巴布韦奇马尼马尼人工松林中狒狒分布型和结群大小与树木剥皮的关系(英文)

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动物学报 2007年第5期53卷 777-782页

作者： D.GWENZI c.a.t.katsvanga G.t.NGORIMA J.F.MUPANGWA S.VALINtINE Department of Environmental Sciences Bindura University of Science Education Department of Agriculture Bindura University of Science Education Border timbers Limited Aberdeen Road

本研究调查了人工松林中狒狒结群大小和家区面积与树木剥皮率的关系。于2003年9月至2004年8月间每月对每个狒狒结群进行5天观察,采用足迹计数法统计狒狒结群大小,对不同结群狒狒家区内具有新旧剥皮的树木数进行统计,以方差分析和回归分... 详细信息

本研究调查了人工松林中狒狒结群大小和家区面积与树木剥皮率的关系。于2003年9月至2004年8月间每月对每个狒狒结群进行5天观察,采用足迹计数法统计狒狒结群大小,对不同结群狒狒家区内具有新旧剥皮的树木数进行统计,以方差分析和回归分析狒狒结群大小和家区面积与树木剥皮之间的关系。结果表明:定居和访问松林的狒狒结群分布型不受结群和家区大小的影响而与季节有关。树木剥皮与狒狒结群大小和家区面积均无相关性,特别是雨季更是如此,揭示狒狒对树木剥皮不是对食物和水源短缺的反应。树木剥皮具有很大的月份间变异,与狒狒群定居和访问利用松林亦无相关。树木剥皮率与狒狒结群大小的关系说明树木剥皮是由于狒狒结群中少数个体的偶然剥皮行为造成的。

关键词：树木剥皮家区人工林定居性结群人工林访问性结群结群大小

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Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen ZHAO Zhenli cHEN c.t.MUtASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

the stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. the oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. the effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. the growth rates of two most unstable modes when δ t equal, and δ = δ*/h*, where δ*and h*are the Stokes-layer thickness and the half height of the channel, respectively. However, their vorticities are different. the vorticity of the most unstable mode is symmetric, while the other is asymmetric. the Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ tabilizing effect when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. the effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. the energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. the effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

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Near resonance vibration isolation on a levered-dual response(LEDAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： t.I.tOLUWALOJU c.K.tHEIN D.HALIM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

the levered-dual response(LEDAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu t.W.Huang K.Jiang c.N.Wu H.Peng P.c.hen R.Li H.B.Zhuo c.t.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

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HI in High Gas-phase Metallicity Dwarf Galaxy WISEA J230615.06+143927.9

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Research in Astronomy and Astrophysics 2024年第1期24卷 292-299页

作者： Yan Guo c.Sengupta t.c.Scott P.Lagos Y.Luo Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China Institute of Astrophysics and Space Sciences(IA Porto) Rua das Estrelas4150-762PortoPortugal

We present resolved Giant Metrewave Radio telescope H I observations of the high gas-phase metallicity dwarf galaxy WISEA J230615.06+143927.9(z = 0.005)(hereafter J2306) and investigate whether it could be a tidal Dwarf Galaxy(tDG) candidate. tDGs are observed to have higher metallicities than normal dwarfs. J2306 has an unusual combination of a blue g-r color of 0.23 mag, irregular optical morphology and high-metallicity(12 +log(O/H) = 8.68 ± 0.14), making it an interesting galaxy to study in more detail. We find J2306 to be an H I rich galaxy with a large extended, unperturbed rotating H I disk. Using our H I data we estimated its dynamical mass and found the galaxy to be dark matter(DM) dominated within its H I radius. the quantity of DM, inferred from its dynamical mass, appears to rule out J2306 as an evolved tDG. A wide area environment search reveals J2306 to be isolated from any larger galaxies which could have been the source of its high gas metallicity. Additionally, the H I morphology and kinematics of the galaxy show no indication of a recent merger to explain the *** detailed optical spectroscopic observations of J2306 might provide an answer to how a seemingly ordinary irregular dwarf galaxy achieved such a high level of metal enrichment.

关键词： galaxies:abundances galaxies:dwarf galaxies:irregular radio lines:galaxies radio lines:ISM

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Radiative decays D*(s)→ D(s)γ in covariant confined quark model

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chinese Physics c 2024年第2期48卷 45-56页

作者： c.t.tran M.A.Ivanov P.Santorelli Q.c.Vo Department of Physics HCMC University of Technology and EducationVo Van Ngan 1700000 Ho Chi Minh CityVietnam Bogoliubov Laboratory of theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia Dipartimento di Fisica"E.Pancini" Universitàdi Napoli Federico ⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto Nazionale di Fisica Nucleare Sezione di Napoli80126 NapoliItaly University of Science 700000 Ho Chi Minh CityVietnam

Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢ*** radiative couplings gD*Dγencoding nonperturbative QcD effects are calculated in the framework of the covariant confined quark model developed by *** compare our results with other theoretical studies and experimental *** couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).the most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QcD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QcD sum rules.

关键词： covariant quark model radiative decay charmed meson

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Decision and coordination of an E-commerce Supply chain considering Returns and Network Externalities

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 552-575页

作者： Liang Shen Fei Lin Yuyan Wang Luping Ding t.c.E.cheng Dexia Wang School of Public Finance and taxation Shandong University of Finance and Economicsjinan 250014China bschool of Management Science and Engineering Shandong University of Finance and EconomicsJinan 250014China PolyU Business School The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China

considering the large number of returns in online sales and the network externalities of e-platforms,we develop a decentralized model and a centralized model to explore the impacts of returns and network externalities on e-commerce supply chain(EcSc)*** show that in the decentralized model,the service level,price,market demand,and EcSc members’profits increase with the network externality ***,the service level and price increase,while the market demand and EcSc members’profits decrease with the product return *** centralized model is the optimal operating mode when it is properly *** design the“commission and return cost-sharing”contract to optimize EcSc,in which the proportion of the e-platform’s sharing of the return handling cost is exactly equal to the proportion of the system profit after *** on the decentralized model,we develop two extended models in which we endogenize the impacts of the service level and return rate on the network externality *** comparisons between the extended and decentralized models,we show that high-quality service can improve EcSc’s profitability,while a high return rate hurts its economic performance.

关键词： E-commerce supply chain coordination mechanism network externalities return products

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Finite barrier bound state

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Light(Science & Applications) 2024年第4期13卷 664-671页

作者： tao Liu Kai Bai Yicheng Zhang Duanduan Wan Yun Lai c.t.chan Meng Xiao Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and technology Wuhan University430072 WuhanChina. National Laboratory of Solid State Microstructures School of Physicsand Collaborative Innovation Center of Advanced MicrostructuresNanjing University210093 NanjingChina. Department of Physics The Hong Kong University of Science and TechnologyClear Water BayKowloon999077Hong KongChina. Wuhan Institute of Quantum technology 430206 WuhanChina

A boundary mode localized on one side of a finite-size lattice can tunnel to the opposite side which results in unwanted *** wisdom tells that the tunneling probability decays exponentially with the size of the system which thus requires many lattice sites before eventually becoming negligibly *** we show that the tunneling probability for some boundary modes can apparently vanish at specific ***,similar to bound states in the continuum,a boundary mode can be completely trapped within very few lattice sites where the bulk bandgap is not even *** intriguingly,the number of trapped states equals the number of lattice sites along the normal direction of the *** provide two configurations and validate the existence of this peculiar finite barrier-bound state experimentally in a dielectric photonic crystal at microwave *** work offers extreme flexibility in tuning the coupling between localized states and channels as well as a new mechanism that facilitates unprecedented manipulation of light.

关键词： boundary state eventually

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thermoluminescence characterization of natural and synthetic irradiated ce-monazites

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Journal of Rare Earths 2024年第4期42卷 643-650页

作者： V.correcher c.Boronat J.Garcia-Guinea J.F.Benavente t.Rivera-Montalvo cIEMAt Av.Complutense 4028040MadridSpain MNcN-cSIc J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

the thermoluminescence(tL)emission of synthetic and natural ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each tL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic cePO_(4):Nd_(0.20),La_(0.25)).the main differences appreciated in these complex tL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).the behavior of the dose response in the range of 1-8 Gy is similar for both samples;the tL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,ce3+?ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODcs or NBOHcs).

关键词： thermoluminescence Kineticparameters Phosphate ce-monazite Defects Rare earths

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