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High-resolution modeling and evaluation of ozone air quality of Osaka using MM5-CMAQ system 被引量:7
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作者 SHRESTHA Kundan Lal KONDO Akira +1 位作者 KAGA Akikazu INOUE Yoshio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期782-789,共8页
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with com... High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with complex terrain and land-use. This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka, Japan. The 1-km and 3-kin grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region. High-resolution Grid Point Value-Mesoscale Model (GPV-MSM) data were used after suitable validation. The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone. Daily maxima of ozone were found better simulated by the 1-krn grid domain than the coarser 9-km and 3-km domains, with the maximum improvement in the mean absolute gross error about 3 ppbv. In addition, 1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation. These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region, such as the Osaka region, which has complex terrain and land-use. 展开更多
关键词 air quality model evaluation OZONE Community Multiscale Air Quality MM5 statistical analysis
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A High-Resolution Modeling Strategy to Assess Impacts of Climate Change for Mesoamerica and the Caribbean
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作者 Robert Oglesby Clinton Rowe +12 位作者 Alfred Grunwaldt Ines Ferreira Franklyn Ruiz Jayaka Campbell Luis Alvarado Francisco Argenal Berta Olmedo Alejandro del Castillo Pilar Lopez Edwards Matos Yosef Nava Carlos Perez Joel Perez 《American Journal of Climate Change》 2016年第2期202-228,共27页
Mesoamerica and the Caribbean are low-latitude regions at risk for the effects of climate change. Global climate models provide large-scale assessment of climate drivers, but, at a horizontal resolution of 100 km, can... Mesoamerica and the Caribbean are low-latitude regions at risk for the effects of climate change. Global climate models provide large-scale assessment of climate drivers, but, at a horizontal resolution of 100 km, cannot resolve the effects of topography and land use as they impact the local temperature and precipitation that are keys to climate impacts. We developed a robust dynamical downscaling strategy that used the WRF regional climate model to downscale at 4 - 12 km resolution GCM results. Model verification demonstrates the need for such resolution of topography in order to properly simulate temperatures. Precipitation is more difficult to evaluate, being highly variable in time and space. Overall, a 36 km resolution is inadequate;12 km appears reasonable, especially in regions of low topography, but the 4 km resolution provides the best match with observations. This represents a tradeoff between model resolution and the computational effort needed to make simulations. A key goal is to provide climate change specialists in each country with the information they need to evaluate possible future climate change impacts. 展开更多
关键词 Regional Climate models Dynamical Downscaling Strategy Mesoamerica and Caribbean Climate Change
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Advancing high-resolution modeling to unravel the interplay between extreme weather events and air pollution under global warming
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作者 Yang Gao Xiuwen Guo +4 位作者 Wenbin Kou Xiaojie Guo Shaoqing Zhang Huiwang Gao Deliang Chen 《Frontiers of Environmental Science & Engineering》 2025年第7期205-212,共8页
Under global warming,extreme weather events and air pollution are becoming increasingly critical challenges.Both pose serious risks to human health,economies,and societal stability,and their complex interactions can f... Under global warming,extreme weather events and air pollution are becoming increasingly critical challenges.Both pose serious risks to human health,economies,and societal stability,and their complex interactions can further amplify these impacts.Numerical models are essential tools for studying these phenomena;however,traditional low-resolution Earth system models often fail to accurately capture the dynamics of extreme weather and air pollution.This limitation hinders our mechanistic understanding,reduces the reliability of future projections,and constrains the development of effective adaptation strategies.Dynamical downscaling—an approach that uses highresolution regional models nested within global models—offers a partial solution.However,this method inherits biases from the parent global models and often fails to adequately represent multi-scale and cross-sphere interactions involving the atmosphere,land,and oceans.These shortcomings underscore the growing need for developing and applying high-resolution Earth system models that can more comprehensively and accurately depict land-sea-atmosphere interactions,including heat and material exchanges and their spatial heterogeneity.This article explores the current challenges,recent advances,and future opportunities in understanding the interplay between extreme weather events and air pollution,with a focus on the critical role of high-resolution modeling. 展开更多
关键词 high-resolution modeling Extreme weather events Air pollution Multiscale and multi-sphere interactions
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High-resolution modeling of modern global continental silicate weathering fluxes within the GEOCLIM model framework:Spatial patterns and controlling factors
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作者 Xiangtong HUANG Yuhua CUI +5 位作者 Yu LIU Fangbing LI Yulong GUO Kai DENG Chao LI Shouye YANG 《Science China Earth Sciences》 2025年第8期2697-2710,共14页
Continental silicate weathering acts as a crucial negative feedback mechanism for removing atmospheric CO_(2) and maintaining Earth's long-term climate stability.However,quantifying continental silicate weathering... Continental silicate weathering acts as a crucial negative feedback mechanism for removing atmospheric CO_(2) and maintaining Earth's long-term climate stability.However,quantifying continental silicate weathering rates and fluxes continues to pose a fundamental challenge in Earth system science.This study utilizes the GEOCLIM carbon cycle model,which integrates modern high-resolution(0.1°×0.1°)datasets on surface temperature,runoff,topography,and lithology to model the spatial distribution of global silicate weathering fluxes.Results indicate a strong correlation between modeled basin-scale outputs and hydrological observations,with weathering rates falling within consistent error margins.Silicate weathering fluxes exhibit distinct latitudinal patterns,with the highest values concentrated within 30°of the equator,accounting for 76.9%of the global total.Continental contributions differ significantly,with Asian river basins representing 36.9%of global fluxes,primarily from Southeast Asia(17.4%),South Asia(8.2%),and East Asia(6.6%).They are followed by South America(29.2%)and Africa(21.7%).Tectonically active regions contribute 21.9%of global silicate weathering,while stable regions account for 72.6%.Multivariate regression analyses using RF and XGBoost machine learning algorithms identify runoff as the primary controlling factor of weathering on a global scale.Weathering in stable regions is jointly regulated by runoff and erosion rates,whereas temperature is the prevailing factor in tectonically active zones.The GEOCLIM model offers a robust framework for quantifying continental weathering processes.Future studies should incorporate organic carbon oxidation,burial,and sulfide oxidation dynamics to clarify carbon cycle interactions and reveal climate-dependent mechanisms for weathering responses and feedback. 展开更多
关键词 Silicate weathering GEOCLIM model River basins Weathering fluxes Carbon cycle
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HUANNet: A High-Resolution Unified Attention Network for Accurate Counting
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作者 Haixia Wang Huan Zhang +2 位作者 Xiuling Wang Xule Xin Zhiguo Zhang 《Computers, Materials & Continua》 2026年第1期1722-1741,共20页
Accurately counting dense objects in complex and diverse backgrounds is a significant challenge in computer vision,with applications ranging from crowd counting to various other object counting tasks.To address this,w... Accurately counting dense objects in complex and diverse backgrounds is a significant challenge in computer vision,with applications ranging from crowd counting to various other object counting tasks.To address this,we propose HUANNet(High-Resolution Unified Attention Network),a convolutional neural network designed to capture both local features and rich semantic information through a high-resolution representation learning framework,while optimizing computational distribution across parallel branches.HUANNet introduces three core modules:the High-Resolution Attention Module(HRAM),which enhances feature extraction by optimizing multiresolution feature fusion;the Unified Multi-Scale Attention Module(UMAM),which integrates spatial,channel,and convolutional kernel information through an attention mechanism applied across multiple levels of the network;and the Grid-Assisted Point Matching Module(GPMM),which stabilizes and improves point-to-point matching by leveraging grid-based mechanisms.Extensive experiments show that HUANNet achieves competitive results on the ShanghaiTech Part A/B crowd counting datasets and sets new state-of-the-art performance on dense object counting datasets such as CARPK and XRAY-IECCD,demonstrating the effectiveness and versatility of HUANNet. 展开更多
关键词 Accurate counting high-resolution representations point-to-point matching
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Integrating high-resolution mass spectrometry and transcriptomics to explore the therapeutic mechanism of Sanhuang Oil in diabetic foot
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作者 Ping Sun Yu-Feng Zhang +4 位作者 Shuang Li Wei Zhang Peng-Fei Zhao Chen-Xia Li Chen-Ning Zhang 《Traditional Medicine Research》 2026年第1期19-38,共20页
Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-... Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-inflammatory,and immunomodulatory activities.However,its active constituents and mechanisms of action against diabetic foot remain to be elucidated.Methods:In this study,the chemical constituents of Sanhuang Oil were identified using UPLC-QE-Orbitrap-MS.Subsequently,the mechanism by which Sanhuang Oil promotes diabetic foot ulcer healing was predicted by integrating network pharmacology and molecular docking.Additionally,diabetic mouse model was established in ICR mice using a combination of a high-fat diet(HFD)and streptozotocin(STZ)chemical induction.A full-thickness skin defect was created on the dorsum of the mice.Wound healing and the healing rate were observed following Sanhuang Oil intervention.The mechanism underlying Sanhuang Oil’s promotion of diabetic ulcer healing was further investigated using transcriptomics and histopathological examination(H&E staining).Results:A total of 97 active ingredients were identified from Sanhuang Oil.Network pharmacology analysis predicted 543 common targets,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis identified 203 relevant pathways.Molecular docking further confirmed high binding affinity(binding energy≤−5.0 kcal/mol)between specific active components in Sanhuang Oil(e.g.,coptisine,phellodendrine,baicalein)and key targets associated with diabetic foot ulcers(e.g.,EGFR,AKT1,STAT3).In vivo experimental results demonstrated that the wound healing rate was significantly higher in Sanhuang Oil-treated groups compared to the model group(P<0.001).HE staining revealed that the high-dose Sanhuang Oil group exhibited more pronounced epithelial tissue coverage over the wound,reduced inflammatory cell infiltration,and increased collagen deposition and fibroblast proliferation.transcriptomic analysis identified Pdk4,Ttn,Csrp3,Actn2,Myoz2,Tnnc2,Myod1,Myog,Myot,and Myf6 as key regulatory proteins involved in promoting wound healing.Conclusion:Sanhuang Oil promotes wound healing in diabetic ulcer mice,potentially by mitigating inflammation and regulating key targets such as Pdk4 to enhance fibroblast function.These findings provide novel insights into the multi-target,multi-pathway mechanism of Sanhuang Oil for treating diabetic foot ulcers. 展开更多
关键词 Sanhuang Oil diabetic foot high-resolution mass spectrometry molecular network analysis mechanism of action
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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC_(1)-LSC_(2)),4 mid-term cycles(MSC_(1)-MSC4)and 7 short-term cycles(SSC_(1)-SSC7).The long-and mid-term cycles correspond to members T_(1)and T_(2)and layers T_(1)-1,T_(1-2),T_(2-1),and T_(2)-2,respectively.Long-term cycles are dominated by C_(1);mid-term cycles are dominated by C_(1)and C_(2),followed by A2;and short-term cycles are dominated by C_(1),C_(2),A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC_(1)-MSC_(2)stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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UAV-to-Ground Channel Modeling:(Quasi-)Closed-Form Channel Statistics and Manual Parameter Estimation
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作者 Zeng Linzhou Liao Xuewen +3 位作者 Xie Wenwu Ma Zhangfeng Xiong Baiping Jiang Hao 《China Communications》 2026年第1期47-66,共20页
(Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbi... (Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbitrary-elevation one-cylinder model.The derived results include a closed-form expression for the space-time correlation function and some quasi-closed-form ones for the space-Doppler power spectrum density,the level crossing rate,and the average fading duration,which are shown to be the generalizations of those previously obtained from the two-dimensional(2-D)one-ring model and the 3-D low-elevation one-cylinder model for terrestrial mobile-to-mobile channels.The close agreements between the theoretical results and the simulations as well as the measurements validate the utility of the derived channel statistics.Based on the derived expressions,the impacts of some parameters on the channel characteristics are investigated in an effective,efficient,and explicable way,which leads to a general guideline on the manual parameter estimation from the measurement description. 展开更多
关键词 channel characteristics geometry-based stochastic model manual parameter estimation UAV channel modeling
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A peridynamics modeling approach for pre-cracked rock cracking processes under impact by integrating Drucker-Prager plasticity model and efficient contact model
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作者 Jingzhi Tu Nengxiong Xu Gang Mei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期179-195,共17页
In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical propert... In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical properties of rocks,the cracking processes of pre-cracked rocks have been extensively studied using numerical modeling methods.The peridynamics(PD)exhibits advantages over other numerical methods due to the absence of the requirements for remeshing and external crack growth criterion.However,for modeling pre-cracked rock cracking processes under impact,current PD implementations lack generally applicable rock constitutive models and impact contact models,which leads to difficulties in determining rock material parameters and efficiently calculating impact loads.This paper proposes a non-ordinary state-based peridynamics(NOSBPD)modeling method integrating the Drucker-Prager(DP)plasticity model and an efficient contact model to address the above problems.In the proposed method,the Drucker-Prager plasticity model is integrated into the NOSBPD,thereby equipping NOSBPD with the capability to accurately characterize the nonlinear stress-strain relationship inherent in rocks.An efficient contact model between particles and meshes is designed to calculate the impact loads,which is essentially a coupling method of PD with the finite element method(FEM).The effectiveness of the proposed NOSBPD modeling method is verified by comparison with other numerical methods and experiments.Experimental results indicate that the proposed method can effectively and accurately predict the 3D cracking processes of pre-cracked cracks under impact loading,and the maximum principal stress is the key driver behind wing crack formation in pre-cracked rocks. 展开更多
关键词 Pre-cracked rocks Cracking processes Non-ordinary state-based peridynamics (NOSBPD) Drucker-Prager plasticity model Efficient contact model
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Constitutive modeling of solvent plasticization and physical aging in glassy polymers
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作者 Xu CAO Kerong WU +1 位作者 Ji LIN Rui XIAO 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期535-554,共20页
Glassy polymers are widely used in biomedical applications in a solvent environment,yet their long-term performance is governed by the competing effects of physical aging and solvent-induced plasticization.Here,we dev... Glassy polymers are widely used in biomedical applications in a solvent environment,yet their long-term performance is governed by the competing effects of physical aging and solvent-induced plasticization.Here,we develop a constitutive model that explicitly couples the solvent concentration,structural relaxation,and mechanical response.This framework is built on a multiplicative decomposition of deformation and an Eyring-type flow rule,with structural evolution described by an effective temperature.A generalized shift factor is introduced to quantify how the solvent concentration and effective temperature jointly affect the relaxation time,thereby integrating physical aging and plasticization.The model is subsequently applied to methacrylate(MA)-based copolymer networks immersed in phosphate-buffered saline for up to nine months.Simulations accurately capture key experimental features,including the strong softening of highly swellable networks,the partial recovery due to aging,and the mitigating role of hydrophobic crosslinking in reducing solvent uptake.While the current single-mode description cannot reproduce the full relaxation spectrum,it establishes an efficient framework for predicting the long-term mechanical performance under coupled environmental and mechanical loading.This study provides a constitutive description of solvent-swollen glassy polymers,offering mechanistic insight into the interplay between plasticization and aging.Beyond biomedical MA networks,this framework establishes a foundation for predicting the long-term performance of polymer glasses under coupled aqueous environmental and mechanical loading. 展开更多
关键词 glassy polymer SWELLING physical aging constitutive model
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Predicting cerebral acetylcholine dynamics with huperzine A pharmacokinetics in blood via mPBPK-PD modeling
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作者 Jiaying Wang Yangfan Zhang +7 位作者 Haoqian Wu Siqi Yu Xiaoying Cai Youying Zhang Jian Chen Zixing Chen Xiao Zheng Haiping Hao 《Chinese Journal of Natural Medicines》 2026年第3期349-364,共16页
Huperzine A(HupA) is a highly selective, reversible acetylcholinesterase(AChE) inhibitor that exhibits neuroprotective effects and is clinically used to manage benign memory decline.However, the specific relationship ... Huperzine A(HupA) is a highly selective, reversible acetylcholinesterase(AChE) inhibitor that exhibits neuroprotective effects and is clinically used to manage benign memory decline.However, the specific relationship between the pharmacokinetic(PK) profile of HupA and cerebral acetylcholine(ACh) dynamics remains poorly characterized. Here, we characterize the PK-pharmacodynamic(PD) properties of HupA in rats under both physiological and pathological conditions. Following a single intramuscular injection, HupA exhibits a short halflife but rapid brain penetration, while multiple dosing significantly enhances its brain exposure. In a middle cerebral artery occlusion(MCAO) rat model, HupA demonstrates increased brain distribution. Furthermore, HupA elevates ACh concentrations across multiple brain regions, concurrently modulating several monoamine neurotransmitters. Using a minimal physiologically based pharmacokinetic-pharmacodynamic(mPBPK-PD) modeling approach,cerebral ACh dynamics were accurately predicted based on the pharmacokinetics of HupA in systemic circulation. The developed mPBPK-PD model exhibits robust predictive performance and holds potential for guiding the optimization of clinical dosing regimens and improving the therapeutic efficacy of HupA. 展开更多
关键词 Huperzine A ACETYLCHOLINESTERASE NEUROPROTECTION ACETYLCHOLINE Ischemic stroke mPBPK-PD MCAO model
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Modeling Pruning as a Phase Transition:A Thermodynamic Analysis of Neural Activations
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作者 Rayeesa Mehmood Sergei Koltcov +1 位作者 Anton Surkov Vera Ignatenko 《Computers, Materials & Continua》 2026年第3期2304-2327,共24页
Activation pruning reduces neural network complexity by eliminating low-importance neuron activations,yet identifying the critical pruning threshold—beyond which accuracy rapidly deteriorates—remains computationally... Activation pruning reduces neural network complexity by eliminating low-importance neuron activations,yet identifying the critical pruning threshold—beyond which accuracy rapidly deteriorates—remains computationally expensive and typically requires exhaustive search.We introduce a thermodynamics-inspired framework that treats activation distributions as energy-filtered physical systems and employs the free energy of activations as a principled evaluation metric.Phase-transition-like phenomena in the free-energy profile—such as extrema,inflection points,and curvature changes—yield reliable estimates of the critical pruning threshold,providing a theoretically grounded means of predicting sharp accuracy degradation.To further enhance efficiency,we propose a renormalized free energy technique that approximates full-evaluation free energy using only the activation distribution of the unpruned network.This eliminates repeated forward passes,dramatically reducing computational overhead and achieving speedups of up to 550×for MLPs.Extensive experiments across diverse vision architectures(MLP,CNN,ResNet,MobileNet,Vision Transformer)and text models(LSTM,BERT,ELECTRA,T5,GPT-2)on multiple datasets validate the generality,robustness,and computational efficiency of our approach.Overall,this work establishes a theoretically grounded and practically effective framework for activation pruning,bridging the gap between analytical understanding and efficient deployment of sparse neural networks. 展开更多
关键词 THERMODYNAMICS activation pruning model compression SPARSITY free energy RENORMALIZATION
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Photometric modeling of ejecta for evaluating defensive Kinetic impacts on asteroids
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作者 XiaoYu Sun ZhiJun Song +4 位作者 XiaoTao Guo XiaoJing Zhang Yuri Skorov Yang Yu He Zhang 《Earth and Planetary Physics》 2026年第1期205-221,共17页
Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evo... Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evolution,and image synthesis to compare directly with HST,LICIACube,ground-based and Lucy observations of the DART impact.Decomposing ejecta into(1)a highvelocity(~1600 m/s)plume exhibiting Na/K resonance,(2)a low-velocity(~1 m/s)conical component shaped by binary gravity and solar radiation pressure,and(3)meter-scale boulders,we quantify each component’s mass and momentum.Fitting photometric decay curves and morphological evolution yields size-velocity distributions and,via scaling laws,estimates of Dimorphos’bulk density,cratering parameters,and cohesive strength that agree with dynamical constraints.Photometric ejecta modeling therefore provides a robust route to constrain momentum enhancement and target properties,improving predictive capability for kinetic-deflection missions. 展开更多
关键词 Kinetic impact DART mission ejecta dynamics photometric modeling
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Modeling eccentric growth explicitly to investigate intra-annual drivers of xylem cell production using xylogenetic data
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作者 Lucie Nina Barbier Marc-Andre Lemay +2 位作者 Etienne Boucher Sergio Rossi Fabio Gennaretti 《Forest Ecosystems》 2026年第1期254-264,共11页
Xylogenesis,the process through which wood cells are formed,results in the long-term storage of carbon in woody biomass,making it a key component of the global carbon cycle.Understanding how environmental drivers infl... Xylogenesis,the process through which wood cells are formed,results in the long-term storage of carbon in woody biomass,making it a key component of the global carbon cycle.Understanding how environmental drivers influence xylogenesis during the growing season is therefore of great interest.However,studying shortterm drivers of wood production using xylogenetic data is complicated by the usual sampling scheme and the influence of eccentric growth,i.e.,heterogeneous growth around the stem.In this study,we improve xylogenesis research by introducing a statistical approach that explicitly considers seasonal phenology,short-term growth rates,and growth eccentricity.To this end,we developed Bayesian models of xylogenesis and compared them with a conventional method based on the use of Gompertz functions.Our results show that eccentricity generated high temporal autocorrelation between successive samples,and that explicitly taking it into account improved both the representativeness of phenology and intra-ring variability.We observed consistent short-term patterns in the model residuals,suggesting the influence of an unaccounted-for environmental variable on cell production.The proposed models offer several advantages over traditional methods,including robust confidence intervals around predictions,consistency with phenology,and reduced sensitivity to extreme observations at the end of the growing season,often linked to eccentric growth.These models also provide a benchmark for mechanistic testing of short-term drivers of wood formation. 展开更多
关键词 XYLOGENESIS Cell production Sampling biases Bayesian model Gompertz function
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Glacial geomorphology and palaeoglacial modeling of Mount Kandil(South of the Lesser Caucasus,Eastern Türkiye)
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作者 ÖZTÜRK Yahya ZORER Halil 《Journal of Mountain Science》 2026年第1期1-28,共28页
Mount Kandil is situated in the eastern sector of the EAHP(Eastern Anatolian High Plateau),to the south of the Lesser Caucasus.The mountain lies at the westernmost end of the Aras Mountains,which extends approximately... Mount Kandil is situated in the eastern sector of the EAHP(Eastern Anatolian High Plateau),to the south of the Lesser Caucasus.The mountain lies at the westernmost end of the Aras Mountains,which extends approximately 80 km along a NW-SE axis.With a summit reaching~3214 m(a.s.l.),Mount Kandil is a stratovolcano that,like many other peaks within the EAHP and the Lesser Caucasus,experienced significant environmental changes during Late Pleistocene.Among these,glacial processes stand out as the most profound,having distinctly shaped the mountains geomorphic landscape.This study presents,for the first time,a comprehensive analysis of the glacial morphology of Mount Kandil based on multiple datasets.Field-based morphological observations indicate that an area of approximately 32.62 km^(2)has been sculpted by glacial activity.Within six glaciated regions on Mount Kandil,25 cirques and 6 glacial valleys have been identified.In addition,moraines in various locations exhibit characteristic morphologies.Furthermore,valley glaciers are inferred to have descended to altitudes as low as~2000 m.The paleoequilibrium line(p ELA)was estimated to use AABR method within GIS,yielding a mean pELA of~2730 m.Ice thickness modelling indicates that the thickness of glaciers in the Kandil Mountain valleys reaches up to~350 m.Due to its orographic extension,Mount Kandil is exposed to humid northwest winds and receives substantial frontal precipitation(~686 mm annually).The compiled geomorphic,cartographic and morphometric parameters suggest that the glaciation dynamics of Mount Kandil—situated between the Southeastern Taurus and the Lesser Caucasus—closely resemble those observed in the Lesser Caucasus.This indicates that glaciation was primarily governed by northern atmospheric systems with additional influences from southerly or westerly winds.The integrated data also underscores the role of multiple atmospheric systems in controlling the glaciation regime around the Lesser Caucasus.Additionally,findings on regional pELA question the common belief that pELA increases eastward in EAHP. 展开更多
关键词 Glacial geomorphology Palaeoglacier modeling Palaeo Ice Mount Kandil Lesser Caucasus
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Time-dependent behavior of deep roadway surrounding rock considering damage induced by excavation and mining disturbances:Experiments,modeling,and simulation
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作者 Qingzhe Cui Rongbin Hou +4 位作者 Zhenhua Li Feng Du Xu Chen Boyang Zhang Lielie Li 《International Journal of Mining Science and Technology》 2026年第2期439-456,共18页
In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicti... In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicting long-term roadway stability,necessitating the development of a reliable constitutive creep model and numerical simulation approach.In this study,creep experiments were conducted on pre-damaged rock with varying initial damage levels to investigate the time-dependent mechanical properties.Based on the experimental results,an accelerated-creep criterion was proposed,and an elastic-viscoplastic creep damage model(EVPCD)was established that simultaneously considers the effects of time-dependent damage and instantaneous damage caused by stress disturbances on rock creep behavior.Subsequently,the effectiveness of the proposed creep model was verified using experimental data,and the secondary development of the EVPCD model was completed based on the FLAC3D platform.Following this,a long-term stability analysis method of deep surrounding rock that accounts for excavation-and mining-induced disturbances was proposed.Using the main roadway of Xutuan Coal Mine as a case study,numerical simulations were carried out to investigate the time-dependent deformation and failure characteristics of the surrounding rock following excavation and mining disturbance.Combined with on-site monitoring of the surrounding rock damage areas,the results indicate that the EVPCD outperforms the CVISC and Nishihara models in predicting the time-dependent behavior of deep surrounding rock. 展开更多
关键词 Initial damage Time-dependent damage Creep model Numerical implementation Damage evolution
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Deformation characteristics of unsaturated slope during post-rainfall earthquake:Insights from centrifuge and numerical modeling
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作者 Jiawei Xu Kun Fang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期380-397,共18页
Slopes are likely to fail in areas with frequent rainfall and earthquakes.The deformation characteristics of unsaturated slopes subjected to post-rainfall earthquakes are investigated using centrifuge model tests and ... Slopes are likely to fail in areas with frequent rainfall and earthquakes.The deformation characteristics of unsaturated slopes subjected to post-rainfall earthquakes are investigated using centrifuge model tests and finite element analyses.Three tests of the slope deformation under earthquake and post-rainfall earthquakes are first studied using image analysis techniques.Then,based on an elastoplastic constitutive model,numerical simulations are carried out using the finite element method and compared with the centrifuge test results.Finally,a parametric study is performed to clarify the effects of antecedent rainfall on earthquake-induced slope deformation.The results show that slope deformation caused by post-rainfall earthquakes differs from that caused by earthquakes without antecedent rainfall.The seepage flow and soil strength of the slope are affected by previous rainfall conditions,such as intensity and duration,which directly influence the slope deformation caused by the subsequent earthquake.Soil displacement and strain become greater and the slip surface is more noticeable during the post-rainfall earthquake of higher intensity.In addition,the time interval between the rainfall and the earthquake has a considerable impact on the detailed characteristics of the slope deformation,and the significant deformation occurs at the time of lowest soil strength when seepage flow reaches the lower part of the slope.Moreover,the repeated intermittent rainfall greatly affects the subsequent earthquake-induced slope deformation,the main characteristics of which are closely related to the changes in saturation and strength of the slope.However,with the prolonged time gap between each round of rainfall,the earthquake-induced slope deformation becomes insignificant. 展开更多
关键词 SLOPE Deformation Post-rainfall earthquake Centrifuge model test Finite element analysis
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Inner Ear Organoids:A Hydrogel-Based Platform for Drug Screening and Deafness Modeling
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作者 Yuyu Cao Xiaotao Liu +1 位作者 Renjie Chai Zuhong He 《Neuroscience Bulletin》 2026年第1期221-232,共12页
This review highlights advances in inner ear organoids(IEOs)as a novel platform for drug screening and disease modeling,particularly for hearing loss.IEOs,derived from embryonic stem cells,induced pluripotent stem cel... This review highlights advances in inner ear organoids(IEOs)as a novel platform for drug screening and disease modeling,particularly for hearing loss.IEOs,derived from embryonic stem cells,induced pluripotent stem cells,or tissue-specific progenitors,provide a physiologically relevant alternative to traditional animal models.Significant progress has been made in utilizing various cell sources,extracellular matrix materials such as Matrigel and hydrogels,and methods for controlling microenvironments through biochemical and biophysical signals.Applications of IEOs in drug screening,disease modeling,and personalized medicine enable exploration of hearing loss mechanisms and therapeutic testing.However,challenges remain,including the incomplete maturation of cochlear cells and difficulty replicating in vivo environments.Future research should focus on optimizing IEO generation,incorporating microfluidic technologies,and advancing high-throughput screening to enhance drug discovery and clinical translation. 展开更多
关键词 Inner ear organoids HYDROGEL Drug screening Hearing loss Disease modeling
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Modeling Hepatitis B and Alcohol Effects on Liver Cirrhosis Progression
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作者 Zia Ur Rahman Nigar Ali +4 位作者 Dragan Pamucar Imtiaz Ahmad Haci Mehmet Baskonus Naseer Ul Haq Zeeshan Ali 《Computer Modeling in Engineering & Sciences》 2026年第1期954-988,共35页
Hepatitis B Virus(HBV)infection and heavy alcohol consumption are the two primary pathogenic causes of liver cirrhosis.In this paper,we proposed a deterministic mathematical model and a logistic equation to investigat... Hepatitis B Virus(HBV)infection and heavy alcohol consumption are the two primary pathogenic causes of liver cirrhosis.In this paper,we proposed a deterministic mathematical model and a logistic equation to investigate the dynamics of liver cirrhosis progression as well as to explain the implications of variations in alcohol consumption on chronic hepatitis B patients,respectively.The intricate interactions between liver cirrhosis,recovery,and treatment dynamics are captured by the model.This study aims to show that alcohol consumption by Hepatitis B-infected individuals accelerates liver cirrhosis progression while treatment of acutely infected individuals reduces it.We proved that a unique solution of the proposed model exists,which is positive and bounded.Using the next-generation matrix approach,two basic reproductive numbers R_(A_(0))and R_(A_(max))are calculated to identify future recurrence.The equilibrium points are calculated,and both equilibria are proved locally and globally asymptotically stable when R_(0)is below and above one,respectively.It is shown that bifurcation exists at R_(0)=1 and a detailed proof for forward bifurcation is given.Furthermore,we performed the sensitivity analysis of the model parameters on R_(0).For the confirmation of analytical work,we performed numerical simulations,and the results indicate that the treatment and the inhibitory effects reduce the risk of developing liver cirrhosis in individuals,while heavy alcohol consumption accelerates markedly the liver cirrhosis progression in patients with chronic hepatitis B. 展开更多
关键词 Liver cirrhosis deterministic model saturated incidence rate STABILITY forward bifurcation
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