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Exogenous nitrogen input skews estimates of microbial nitrogen use efficiency by ecoenzymatic stoichiometry

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Ecological Processes 2023年 625-631页

Background Ecoenzymatic stoichiometry models（EEST） are often used to evaluate microbial nutrient use efficiency,but the validity of these models under exogenous nitrogen（N） input has never been clarified. Here, we investigated the effects of long-term N addition（as urea） on microbial N use efficiency（NUE）, compared EEST and18O-labeling methods for determining NUE, and evaluated EEST's theoretical assumption that the ratios of standard ecoenzymatic activities balance resource availability with microbial *** We found that NUE estimated by EEST ranged from 0.94 to 0.98. In contrast, estimates of NUE by the18O-labeling method ranged from 0.07 to 0.30. The large differences in NUE values estimated by the two methods may be because the sum of β-N-acetylglucosaminidase and leucine aminopeptidase activities in the EEST model was not limited to microbial N acquisition under exogenous N inputs, resulting in an overestimation of microbial NUE by EEST. In addition, the acquisition of carbon by N-acquiring enzymes also likely interferes with the evaluation of NUE by *** Our results demonstrate that caution must be exercised when using EEST to evaluate NUE under exogenous N inputs that may skew standard enzyme assays.

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Trade-off between microbial carbon use efficiency and specific nutrient-acquiring extracellular enzyme activities under reduced oxygen

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Soil Ecology letters 2023年第2期5卷 43-53页

作者： Ji Chen Irene Cordero daryl l.moorhead Jennifer K.Rowntree lorae T.Simpson Richard D.Bardgett Hayley Craig Department of Agroecology Aarhus University8830 TjeleDenmark Aarhus University Centre for Circular Bioeconomy Aarhus University8830 TjeleDenmark iClIMATE Interdisciplinary Centre for Climate Change Aarhus University4000 RoskildeDenmark Department of Earth and Environmental Sciences The University of ManchesterOxford RoadManchesterM139PTUK Department of Environmental Sciences University of Toledo2801 W.Bancroft St.ToledoOH 43606-3390USA School of Biological and Marine Sciences University of PlymouthDrake CircusPlymouthPL48AAUK Florida Oceanographic Society 890 NE Ocean BlvdStuartFL 34996USA NatureMetrics Occam CourtSurrey Research ParkGuildfordGU27HJUK

Mangroves are one of the most ecologically sensitive ecosystems to global climate change,which have cascading impacts on soil carbon(C),nitrogen(N)and phosphorus(P)***,mangroves are experiencing increasing N and P loadings and reduced oxygen availability due to intensified climate change and human ***,both direct and interactive effects of these perturbations on microbially mediated soil C,N and P cycling are poorly ***,we simultaneously investigated the effects of N and P loadings and reduced oxygen on microbial biomass,microbial respiration,and extracellular enzyme activities(EEAs)in mangrove *** calculated the microbial metabolic quotient(qCO_(2)),which is regarded as a useful inverse metric of microbial C use efficiency(CUE).Our results show that reduced oxygen significantly increases both qCO_(2) and microbial specific EEAs(enzyme activity per unit of microbial biomass)for C-,N-and P-acquisition regardless of N or P ***,we found that qCO_(2) positively correlated with microbial specific EEAs under reduced oxygen,whereas no clear relationship was detected under ambient *** results suggest that reduced oxygen increases microbial specific EEAs at the expense of increasing microbial respiration per unit biomass,indicating higher energy cost per unit enzyme production.

关键词： reduced oxygen extracellular enzyme microbial respiration nutrient acquisition nutrient addition mangrove

长期夜间高温对9个大豆品种营养生长期的影响

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种子 2024年第7期43卷 81-90,96页

作者：舒天楚 daryl Chastain 奥本大学美国阿拉巴马州奥本市36849 密西西比州立大学美国密西西西比州斯通维尔市38776

为探究夜间高温对大豆从播种到花期的生理影响,确定大豆由长期夜间高温产生的表型变异是否由基因型差异引起,对9个大豆品种从播种到花期施加极端夜间高温(EHNT,30℃/30℃,昼/夜),研究此环境对大豆生理指标和营养生长的影响。测量指标包... 详细信息

为探究夜间高温对大豆从播种到花期的生理影响,确定大豆由长期夜间高温产生的表型变异是否由基因型差异引起,对9个大豆品种从播种到花期施加极端夜间高温(EHNT,30℃/30℃,昼/夜),研究此环境对大豆生理指标和营养生长的影响。测量指标包括:光合作用速率、呼吸作用速率、叶绿素含量和荧光分析。结果表明,在高光照强度[1 750μmol/(m^(2)·s)]下的营养生长阶段长期极端夜间高温降低了光合速率、气孔导度、叶绿素含量和PSⅡ效率(Fv/Fm),但不改变呼吸作用速率。从显著降低的这些生理指标中观察到了品种变异。部分品种通过未产生变化的地上部生物量显示出对极端夜间高温的耐受性。在大豆品种S14-15146R和DS25-1中,极端夜间高温耐受性可能与PSⅡ的光化学效率(Fv/Fm)有关。

关键词：夜间高温大豆 Fv/Fm 光合作用营养生长期

A Pooling Method Developed for Use in Convolutional Neural Networks

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 751-770页

作者： Ìsmail Akgül Departmant of Computer Engineering Faculty of Engineering and ArchitectureErzincan Binali Yıldırım UniversityErzincan24002Turkiye

In convolutional neural networks,pooling methods are used to reduce both the size of the data and the number of parameters after the convolution of the *** methods reduce the computational amount of convolutional neural networks,making the neural network more *** pooling,average pooling,and minimum pooling methods are generally used in convolutional neural ***,these pooling methods are not suitable for all datasets used in neural network *** this study,a new pooling approach to the literature is proposed to increase the efficiency and success rates of convolutional neural *** method,which we call MAM(Maximum Average Minimum)pooling,is more interactive than other traditional maximum pooling,average pooling,and minimum pooling methods and reduces data loss by calculating the more appropriate pixel *** proposed MAM pooling method increases the performance of the neural network by calculating the optimal value during the training of convolutional neural *** determine the success accuracy of the proposed MAM pooling method and compare it with other traditional pooling methods,training was carried out on the leNet-5 model using CIFAR-10,CIFAR-100,and MNIST *** to the results obtained,the proposed MAM pooling method performed better than the maximum pooling,average pooling,and minimum pooling methods in all pool sizes on three different datasets.

关键词： Pooling convolutional neural networks deep learning

On the functions of astrocyte-mediated neuronal slow inward currents

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Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs Pál Department of Physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,Parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current

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

Quantum vortices get stretched

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Frontiers of physics 2024年第3期19卷 225-227页

作者： Emanuel A.l.Henn São Carlos Institute of Physics University of São Paulo-PO Box 36913560-970São CarlosBrazil

Since its discovery, superfluidity [1,2] remains one of the most remarkable phenomena in quantum physics. The onset of the quantum regime in liquid helium is visually striking, when the fluid flows without dissipation or detaches from a rotating bucket, remaining still upon soft rotations. The same phenomenon is present in the context of ultracold bosonic quantum gases where, most of the time, superfluidity walks hand-in-hand with the transition to Bose−Einstein condensation [3].

关键词： quantum rotating rotation

Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China Mathematics 2024年第1期67卷 211-236页

作者： Qi lü Bowen Ma School of Mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy

Rogue wave solutions and rogue-breather solutions to the focusing nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 33-41页

作者： Si-Jia Chen Xing lü College of Science Tianjin University of TechnologyTianjin 300384People's Republic of China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044People's Republic of China Beijing laboratory of National Economic Security Early-warning Engineering Beijing Jiaotong UniversityBeijing 100044People's Republic of China

Based on the long wave limit method,the general form of the second-order and third-order rogue wave solutions to the focusing nonlinear Schr?dinger equation are given by introducing some arbitrary *** interaction solutions between the first-order rogue wave and one-breather wave are constructed by taking a long wave limit on the two-breather *** applying the same method to the three-breather solutions,two types of interaction solutions are obtained,namely the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,*** influence of the parameters related to the phase on the interaction phenomena is graphically *** occur among the rogue waves and breather *** the collisions,the shape of them remains *** abundant interaction phenomena in this paper will contribute to a better understanding of the propagation and control of nonlinear waves.

关键词： nonlinear Schrodinger equation rogue wave solutions interaction solutions