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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche c.calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(fra.c.)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest canopy Resorption Foliar leaching Senesced leaves Nutrition

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crystal structure and lum.nescence dynam.cs of highly pure Lim.PO_(3))_(3):Eu^(3+)(m.Sr,ca) red phosphors for white light em.tting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria m.m.nhas A.K.Bedyal Ankush Vij H.c.Swart Vinay Kum.r Departm.nt of Physics and Astronom.cal Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Departm.nt of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Departm.nt of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Departm.nt of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors Lim.PO_(3))_(3):Eu^(3+)(m.Sr,ca) doped with Eu^(3+)(1 m.l%) were synthesized via solution com.ustion m.thod and their crystal structure and lum.nescence dynam.cs were studied to explore its suitability in white light em.tting *** Rietveld refinem.nt analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and Lica(PO_(3)) with space group P-1(2).The scanning electron m.croscopy im.ges showed the agglom.rated *** photolum.nescence em.ssion spectra under 393 nm.show an orange band at 594 nm.and a red band at 613 nm.ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as lum.nescence behaviour,and Stark splitting were used to exam.ne the sym.etry of Eu^(3+)ions in Lim.PO_(3))_(3):Es^(3+)(m.Sr,ca) phosphors in term. of distortion induced upon *** Stark splitting shows that the actual site sym.etry for Eu^(3+)ion was estim.ted to be D_(2) type for both *** photom.tric properties of Lica(PO_(3))_(3):Eu^(3+)such as com.ission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red com.onent in n-UV white light em.tting diodes.

关键词： Photolum.nescence Phosphate WLEDs Stark splitting Rare earths

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consum.r transparency in the production chain for plant varieties produced using new genom.c techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz c.c.m.van de Wiel L.A.P.Lotz m.J.m.Sm.lders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genom.c techniques(NGTs)currently fall under the Genetically m.dified Organism. Directive(2001/18/Ec)in the European *** the proposal of the European com.ission,NGT plants are partially exem.ted from.the regulations of this *** proposal m.kes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consum.r,although they will be labelled as ***-2 category plants m.y be labelled with additional inform.tion as a positive *** of seeds of varieties m.de with gene editing,but not the products,would m.an that m.st steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a com.on them. in food labelling towards ***,we describe current labelling regim.s and registers and how these m.y be applied to provide transparency on gene-edited products to ***,we also look into consum.r studies,which indicate a greater acceptance of gene-edited food am.ng consum.rs,especially when additional benefits such as sustainability are m.ntioned.

关键词： Labelling New genom.c techniques consum.r transparency Plant products

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Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.ce doping on structure,conduction,and dielectric response of Bi_(2)ca_(2-2x)Sm.(x)cexcoO_(6)(x=0.000,0.025,0.050,0.075)(BcSccO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BcSccO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of Bi_(2)ca_(2)coO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the BcSccO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n Bi_(2)ca_(1.9)0Sm.(0.05)0ce_(0.05)_(0)coO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BcSccO) Spreading factor conduction m.chanism Rare earths

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Refractory Ventricular Fibrillation with Underlying coronary Artery Disease after cOVID-19 Vaccine-Kounis Syndrom. or coincidence

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case Reports in clinical m.dicine 2024年第8期13卷 309-314页

作者： Elaine m. c. chau cardiology centre Hong Kong Sanatorium & Hospital Hong Kong SAR China

A 63-year-old m.n with diabetes and asym.tom.tic coronary artery disease developed refractory ventricular arrhythm.a at 20 hours at rest after his second cOVID-19 vaccine. Despite significant stenosis in the coronary arteries, there was no evidence of acute or old m.ocardial infarction, heart failure, m.ocarditis or structural abnorm.lities on post-m.rtem.to account for the substrate for the fatal arrhythm.a. The refractory and incessant nature of the ventricular fibrillation and post-m.rtem.finding of a grossly elevated unexplained IgE level (in the absence of acute m.ocardial infarction) suggested the possibility of Kounis Syndrom. or allergic acute coronary syndrom..

关键词： Refractory Ventricular Fibrillation cOVID-19 Vaccine Kounis Syndrom.

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Perform.nce of evolutionary optim.zed m.chine learning for m.deling total organic carbon in core sam.les of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt c.m.Saporetti L.c.Oliveira E.Pereira Departm.nt of com.utational and Applied m.chanics Federal University of Juiz de ForaJuiz de ForaBrazil Departm.nt of com.utational m.deling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Departm.nt of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock sam.les'TOc content is the best indicator of the organic m.tter in source *** origin rock sam.les’analysis is used to calculate it m.nually by *** m.thod requires tim. and resources because it relies on sam.les from.m.ny well intervals in source ***,research has been done to aid this *** learning algorithm. can estim.te total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on autom.ting the total organic carbon estim.tion using m.chine learning approaches im.roved by an evolutionary m.thodology to give the m.del flexibility and *** algorithm.,differential evolution,particle swarm.optim.zation,grey wolf optim.zation,artificial bee colony,and evolution strategies were used to im.rove m.chine learning m.dels to predict *** six m.taheuristics were integrated into four m.chine learning m.thods:extrem. learning m.chine,elastic net linear m.del,linear support vector regression,and m.ltivariate adaptive regression *** sam.les from.the YuDong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that com.ining m.chine learning m.dels with an evolutionary algorithm. in a hybrid fashion produce flexible m.dels that accurately predict *** results show that,independent of the m.taheuristic used to guide the m.del selection,optim.zed extrem. learning m.chines attained the best perform.nce scores according to six *** hybrid m.dels can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid m.dels Autom.ted m.chine learning Evolutionary algorithm. Geology

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cooperative Target Fencing of m.ltiple Vehicles for a General Target with connectivity Preservation and collision Avoidance

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Journal of System. Science & com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini cHEN Ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull form.d by the ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. networked system. target fencing

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An im.roved pulse coupled neural networks m.del for sem.ntic IoT

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Digital com.unications and Networks 2024年第3期10卷 557-567页

作者： Rong m. Zhen Zhang Yide m. Xiping Hu Edith c.H.Ngai Victor c.m.Leung School of Inform.tion Science and Engineering Lanzhou UniversityLanzhou 730000China School of m.dical Technology Beijing Institute of TechnologyBeijing100081China Departm.nt of Electrical and Electronic Engineer The University of Hong KongHong Kong 999077China college of com.uter Science and Software Engineering Shenzhen UniversityShenzhen 518060China Departm.nt of Electrical and com.uter Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in m.bile data ***,with the rapid developm.nt of artificial intelligence,sem.ntic com.unication has attracted great attention as a new com.unication ***,for IoT devices,however,processing im.ge inform.tion efficiently in real tim. is an essential task for the rapid transm.ssion of sem.ntic *** the increase of m.del param.ters in deep learning m.thods,the m.del inference tim. in sensor devices continues to *** contrast,the Pulse coupled Neural Network(PcNN)has fewer param.ters,m.king it m.re suitable for processing real-tim. scene tasks such as im.ge segm.ntation,which lays the foundation for real-tim.,effective,and accurate im.ge ***,the param.ters of PcNN are determ.ned by trial and error,which lim.ts its *** overcom. this lim.tation,an Im.roved Pulse coupled Neural Networks(IPcNN)m.del is proposed in this *** IPcNN constructs the connection between the static properties of the input im.ge and the dynam.c properties of the neurons,and all its param.ters are set adaptively,which avoids the inconvenience of m.nual setting in traditional m.thods and im.roves the adaptability of param.ters to different types of *** segm.ntation results dem.nstrate the validity and efficiency of the proposed self-adaptive param.ter setting m.thod of IPcNN on the gray im.ges and natural im.ges from.the m.tlab and Berkeley Segm.ntation *** IPcNN m.thod achieves a better segm.ntation result without training,providing a new solution for the real-tim. transm.ssion of im.ge sem.ntic inform.tion.

关键词： Internet of things(IoT) Sem.ntic inform.tion Real-tim. application Im.roved pulse coupled neural network Im.ge segm.ntation

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Optim.zation of a photovoltaic-battery system.using deep reinforcem.nt learning and load forecasting

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Energy and AI 2024年第2期16卷 168-183页

作者： António corte Real G.Pontes Luz J.m.c.Sousa m.c.Brito S.m.Vieira IDm.c Instituto Superior TécnicoUniversidade de LisboaLisboa1049-001Portugal Instituto Dom.Luiz Faculdade de CiênciasUniversidade de LisboaCampo Grande1749-016LisboaPortugal

Hom. Energy m.nagem.nt System.(HEm.)are increasingly relevant for dem.nd-side m.nagem.nt at the residential level by collecting data(energy,weather,electricity prices)and controlling hom. appliances or storage *** control can be perform.d with classical m.dels that find optim.l solutions,with high real-tim. com.utational cost,or data-driven approaches,like Reinforcem.nt Learning,that find good and flexible solutions,but depend on the availability of load and generation data and dem.nd high com.utational resources for *** this work,a novel HEm. is proposed for the optim.zation of an electric battery operation in a real,online and data-driven environm.nt that integrates state-of-the-art load forecasting com.ining cNN and LSTm.neural networks to increase the robustness of *** Reinforcem.nt Learning agents are trained with different algorithm.(Double DQN,Dueling DQN,Rainbow and Proxim.l Policy Optim.zation)in order to m.nim.ze the cost of electricity purchase and to m.xim.ze photovoltaic self-consum.tion for a PV-Battery residential *** show that the best Reinforcem.nt Learning agent achieves a 35%reduction in total cost when com.ared with an optim.zation-based agent.

关键词： Energy m.nagem.nt system Deep reinforcem.nt learning Dem.nd-side m.nagem.nt Load forecasting Deep learning Energy storage system.

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Sem.-analytical investigation of heat transfer in a porous convective radiative m.ving longitudinal fin exposed to m.gnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied m.them.tics and m.chanics(English Edition) 2024年第1期45卷 197-216页

作者： c.G.PAVITHRA B.J.GIREESHA m.L.KEERTHI Departm.nt of PG Studies and Research in m.them.tics Kuvempu UniversityShankaraghatta 577451India Departm.nt of m.them.tics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The therm.l exam.nation of a non-integer-ordered m.bile fin with a m.gnetism.in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The com.ination approach is utilized to evaluate the physical and therm.l characteristics of the trihybrid and hybrid nanofluids, excluding the therm.l conductivity and dynam.c viscosity. These two properties are inferred by m.ans of the interpolation m.thod based on the volum. fraction of nanoparticles. The governing equation is transform.d into a dim.nsionless form. and the Adom.an decom.osition Sum.du transform.m.thod(ADSTm. is adopted to solve the conundrum.of a m.ving fin im.ersed in a trihybrid nanofluid. The obtained results agree well with those num.rical sim.lation results, indicating that this research is reliable. The influence of diverse factors on the therm.l overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furtherm.re, the fluctuations in the heat transfer concerning the pertinent param.ters are studied. The results show that the heat flux in the presence of the com.ination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the com.ination of only spherical and cylindrical nanoparticles. The tem.erature at the fin tip increases by 0.705 759% when the value of the Peclet num.er increases by 400%, while decreases by 11.825 13% when the value of the Hartm.n num.er increases by 400%.

关键词： convection radiation m.ving longitudinal fin Adom.an decom.osition Sum.du transform.m.thod(ADSTm. trihybrid nanofluid m.gnetic field

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