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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： sisira Ediriweera Champika Bandara Tithira Lakkana shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.singhakumara Xiangcheng Mi I.A.U.N.Gunatilleke C.v.s.Gunatilleke Mark sAshton Department of science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest school Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental science University of Sri JayewardenepuraNugegodaSri Lanka state Key Laboratory of vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats shorea spp. southeast Asia sri Lanka Tropical rain forest Wood specific gravity

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Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCs Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alexey v.Kuzmin Maxim A.Faraonov Evgenii N.Ivanov salavat s.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri v.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAs 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of solid-state Physics RAs 142432 Chernogolovka Research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov Institute of solution Chemistry of the Russian Academy of sciences 153045 Ivanovo Institute for Advanced Research in Chemical sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

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Liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： sANDRO C.OLIvEIRA MARIA s.sOAREs BÁRBARA v.GONÇALvEs ANDREIA C.M.RODRIGUEs AMADEU M.v.M.sOAREs RITA G.sOBRAL NUNO F.sANTOs JAN NEDOMA PEDRO L.ALMEIDA CARLOs MARQUEs CICECO-Aveiro Institute of Materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3N Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CEsAM-Centre for Environmental and Marine studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3N-CENIMAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized *** is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we developed optical immunosensors for the selective detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal molecules by using DMOAP during *** presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关键词： crystal alignment analysis

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Wormhole solutions under the effect of dark matter in f(R,L_(m))gravity

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Communications in Theoretical Physics 2024年第5期76卷 102-113页

作者： Lakhan v Jaybhaye Moreshwar Tayde PK sahoo Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In the background of f(R,L_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo *** current study aims to accomplish these goals by examining various dark matter profiles including universal rotation curves(URC),Navarro-Frenk-White(NFW)model-Ⅰ,and NFW model-Ⅱinside two distinct f(R,L_(m))gravity *** to the f(R,L_(m))=R/2+L^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting the wormhole geometries with appropriate choice of free *** addition,to examine DM profiles under the f(R,L_(m))=R/2+(1+λR)L_(m) model,we consider a specific shape ***,we observed that the derived solution from both two models violates the null energy constraints,confirming that the DM supports wormholes to maintain in the galactic halo.

关键词： f(R L_(m))gravity wormhole dark matter(some figures may appear in colour only in the online journal)

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Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOv Ekaterina v.LEBEDEvA Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： volcanic lakes Echolocation survey volcanism Gashydrotherms Kamchatka Kuril Islands

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Electrostatic Interaction-directed Construction of Hierarchical Nanostructured Carbon Composite with Dual Electrical Conductive Networks for Zinc-ion Hybrid Capacitors with Ultrastability

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Energy & Environmental Materials 2024年第1期7卷 188-196页

作者： Changyu Leng Zongbin Zhao Xuzhen Wang Yuliya v.Fedoseeva Lyubov G.Bulusheva Alexander v.Okotrub Jian Xiao Jieshan Qiu state Key Lab of Fine Chemicals School of Chemical Engineering Liaoning Key Lab for Energy Materials and Chemical Engineering Dalian University of Technology Nikolaev Institute of Inorganic Chemistry Siberian Branch of the Russian Academy of Sciences College of Chemical Engineering Beijing University of Chemical Technology

Metal-organic framework(MOF)-derived carbon composites have been considered as the promising materials for energy ***,the construction of MOF-based composites with highly controllable mode via the liquid-liquid synthesis method has a great challenge because of the simultaneous heterogeneous nucleation on substrates and the self-nucleation of individual MOF nanocrystals in the liquid phase.

关键词： carbon composite electrostatic interaction metal–organic framework coating self-assembly zinc-ion hybrid capacitor

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Investigation of crack segmentation and fast evaluation of crack propagation, based on deep learning

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Frontiers of structural and Civil Engineering 2024年第4期18卷 516-535页

作者： Than v.TRAN H.NGUYEN-XUAN Xiaoying ZHUANG Institute of Photonics Leibniz University HannoverHannover 30167Germany CIRTech Institute HUTECH UniversityHo Chi Minh City 700000Vietnam College of Civil Engineering Tongji UniversityShanghai 200092China

Identifying crack and predicting crack propagation are critical processes for the risk assessment of engineering *** traditional approaches to crack modeling are faced with issues of high computational costs and excessive computing *** address this issue,we explore the potential of deep learning(DL)to increase the efficiency of crack detection and forecasting crack ***,there is no single algorithm that can fit all data sets well or can apply in all cases since specific tasks *** the paper,we present DL models for identifying cracks,especially on concrete surface images,and for predicting crack ***,segNet and U-Net networks are used to identify concrete *** gradient descent(sGD)and adaptive moment estimation(Adam)algorithms are applied to minimize loss function during ***,time series algorithms including gated recurrent unit(GRU)and long short-term memory(LsTM)are used to predict crack *** experimental findings indicate that the U-Net is more robust and efficient than the segNet for identifying crack segmentation and achieves the most outstanding *** evaluation of crack propagation,GRU and LsTM are used as DL models and results show good agreement with the experimental data.

关键词： deep learning crack segmentation crack propagation encoder−decoder recurrent neural network

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Energy-efficient joint UAv secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

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Defence Technology（防务技术） 2024年第1期31卷 537-543页

作者： Huang Hailong Mohsen Eskandari Andrey v.savkin Wei Ni The Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHong KongChina school of Electrical Engineering and Telecommunications University of New South WalesSydney2052Australia Data61 CSIROAustralia

We consider a scenario where an unmanned aerial vehicle(UAv),a typical unmanned aerial system(UAs),transmits confidential data to a moving ground target in the presence of multiple *** friendly reconfigurable intelligent surfaces(RIss) help to secure the UAv-target communication and improve the energy efficiency of the *** formulate an optimization problem to minimize the energy consumption of the UAv,subject to the mobility constraint of the UAv and that the achievable secrecy rate at the target is over a given *** present an online planning method following the framework of model predictive control(MPC) to jointly optimize the motion of the UAv and the configurations of the *** effectiveness of the proposed method is validated via computer simulations.

关键词： Unmanned aerial systems(UAss) Unmanned aerial vehicle(UAv) Communication security Eaves-dropping Reconfigurable intelligent surfaces(RIs) Autonomous navigation and placement Path planning Model predictive control

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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

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CoopAI-Route: DRL Empowered Multi-Agent Cooperative system for Efficient Qos-Aware Routing for Network slicing in Multi-Domain sDN

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Computer Modeling in Engineering & sciences 2024年第9期140卷 2449-2486页

作者： Meignanamoorthi Dhandapani v.vetriselvi R.Aishwarya College of Engineering Guindy Anna UniversityChennai600025India

The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global *** slicing is crucial in delivering services for different,demanding vertical applications in this ***-generation applications have time-sensitive requirements and depend on the most efficient routing path to ensure packets reach their intended ***,the existing IP(Internet Protocol)over a multi-domain network faces challenges in enforcing network slicing due to minimal collaboration and information sharing among network *** inter-domain routing methods,like Border Gateway Protocol(BGP),cannot make routing decisions based on performance,which frequently results in traffic flowing across congested paths that are never *** address these issues,we propose CoopAI-Route,a multi-agent cooperative deep reinforcement learning(DRL)system utilizing hierarchical software-defined networks(sDN).This framework enforces network slicing in multi-domain networks and cooperative communication with various administrators to find performance-based routes in intra-and ***-Route employs the Distributed Global Topology(DGT)algorithm to define inter-domain Quality of service(Qos)***-Route uses a DRL agent with a message-passing multi-agent Twin-Delayed Deep Deterministic Policy Gradient method to ensure optimal end-to-end routes adapted to the specific requirements of network slicing *** evaluation demonstrates CoopAI-Route’s commendable performance in scalability,link failure handling,and adaptability to evolving topologies compared to state-of-the-art methods.

关键词： 6G multi-domain multi-agent routing DRL sDN

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