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Lifespan Estimates of Solutions to the Tricomi Equation with Memory Terms
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作者 YANG Jie YAO Jiangyan 《应用数学》 北大核心 2026年第2期605-623,共19页
The main purpose of this paper is to investigate the singularities of solutions to the single Tricomi equation with derivative term and combined memory term.In addition,the blow-up of the solution to the weakly couple... The main purpose of this paper is to investigate the singularities of solutions to the single Tricomi equation with derivative term and combined memory term.In addition,the blow-up of the solution to the weakly coupled system with memory term is also considered,where one is a power nonlinear term and the other is a derivative nonlinear term.Upper bound lifespan estimates of solution are obtained in the sub-critical by utilizing the test function method and iteration technique.The innovation of this paper focuses on the lifespan estimates of the solutions,which extends the well-known Strauss and Glassey conjectures. 展开更多
关键词 Tricomi equation Memory term Semilinear weakly coupled system Test function method Iteration method
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Detection of the Oscillation Marks on Casting Slabs Using Magnetic Flux Variation and the Nonexcitation Method
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作者 FENG Kaibin LIU Runcong +3 位作者 LI Silong WU Yunfei NA Xianzhao WANG Xiaodong 《材料导报》 北大核心 2026年第1期149-158,共10页
T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection met... T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection methods face challenges owing to surface oxide scales,and conventional high-precision magnetic sensors are ineffective at high temperatures.To overcome these limitations,a small coil sensor was employed to measure the residual magnetism strength in oscillation traces,using metal magnetic memory and electromagnetic induction methods,which can carry out detection without an external excitation source.Using this technology,the proposed scheme successfully detects defects at high tempe-ratures(up to 670℃)without a cooling device.The key findings include the ability to detect both surface and near-surface defects,such as cracks and oscillation marks,with an enhanced signal-to-noise ratio(SNR)of 7.2 dB after signal processing.The method’s practicality was validated in a steel mill environment,where testing on casting slabs effectively detected defects,providing a foundation for improving industrial quality control.The proposed detection scheme offers a significant advancement in nondestructive testing(NDT)for high-temperature applications,contributing to more efficient and accurate monitoring of ferromagnetic material integrity. 展开更多
关键词 oscillation marks REMANENCE metal magnetic memory near surface defects nondestructive testing(NDT)
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气候变化背景下河南省耕地气候生产潜力时空演变特征分析
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作者 项鑫 马泉来 +3 位作者 孙晓兵 杨延伟 路中 周浩 《水土保持研究》 北大核心 2026年第3期408-418,共11页
[目的]充分挖掘耕地气候生产潜力,为提升区域耕地粮食生产能力提供理论参考。[方法]利用气候、耕地利用等数据,采用Thornthwaite Memorial模型测算耕地气候生产潜力,借助Theil-Sen趋势分析、Mann-Kendall统计检验、变异系数等方法以及... [目的]充分挖掘耕地气候生产潜力,为提升区域耕地粮食生产能力提供理论参考。[方法]利用气候、耕地利用等数据,采用Thornthwaite Memorial模型测算耕地气候生产潜力,借助Theil-Sen趋势分析、Mann-Kendall统计检验、变异系数等方法以及构建的耕地气候生产潜力总量和耕地气候资源利用率等指标,分析了河南省耕地气候生产潜力的时空演变特征。[结果](1)1990—2023年河南省温度和降水均值范围分别为5.57~16.79℃和556.90~1490.31 mm,以10年为期限的均值分别呈现稳步增加和先增加后降低的趋势。(2)1990—2023年河南省耕地气候生产潜力呈现波动增加的趋势,多年均值为12599.93 kg/hm^(2),总体呈现南高北低的特点,且具有显著的空间差异性,以较低波动、中度波动和较高波动为主。(3)1990—2023年耕地气候生产潜力总量呈现波动降低的趋势,年均值为1.43亿t,变异系数为6.60%;耕地和主要粮食作物(小麦、玉米和大豆)的气候资源利用率总体呈现波动增加的趋势,多年均值分别为40.26%,41.84%,41.08%和14.15%,且不同时段的气候资源利用率变化具有较为显著的差异性。(4)河南省耕地气候生产潜力以不显著增加为主,面积占比为72.07%,广泛分布于河南省中部、东部、中北部、中南部等区域;极显著减少面积占比为6.47%,零星分布于各个地市,但多集中分布于城市周边。[结论]河南省耕地气候生产潜力具有较为显著的空间差异特征,因地制宜地合理调控作物布局和通过土壤改良增强其保水保肥能力可进一步挖掘耕地粮食产出能力。 展开更多
关键词 气候要素 耕地气候生产潜力 Thornthwaite Memorial模型 时空变化 河南省
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基于ARIMA-LSTM模型的MSWI过程CO_(2)排放浓度多步预测
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作者 汤健 王子 +2 位作者 夏恒 王天峥 乔俊飞 《北京工业大学学报》 北大核心 2026年第2期175-188,共14页
针对城市固废焚烧(municipal solid waste incineration,MSWI)过程CO_(2)排放兼具线性趋势与非线性波动的复杂动态特性,现有单一预测难以准确拟合的问题,提出基于差分整合移动平均自回归-长短期记忆(autoregressive integrated moving a... 针对城市固废焚烧(municipal solid waste incineration,MSWI)过程CO_(2)排放兼具线性趋势与非线性波动的复杂动态特性,现有单一预测难以准确拟合的问题,提出基于差分整合移动平均自回归-长短期记忆(autoregressive integrated moving average-long short-term memory,ARIMA-LSTM)模型的CO_(2)排放浓度的多步预测方法。首先,采用ARIMA算法构建线性主模型以进行CO_(2)排放浓度预测;然后,以主模型的预测残差为真值,采用LSTM算法构建非线性补偿模型;最后,将主模型和补偿模型的预测值进行组合得到超前多步的预测结果。基于北京某MSWI工厂的真实CO_(2)数据集验证了所构建混合模型的有效性。 展开更多
关键词 城市固废焚烧(municipal solid waste incineration MSWI) CO_(2)排放 多步预测 差分整合移动平均自回归模型 长短期记忆(long short-term memory LSTM)网络 混合模型
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Role of 5-hydroxytryptamine type 3 receptors in aerobic exercise-induced improvement of memory and hippocampal synaptic plasticity
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作者 Xiaoqian He Ziying Lai +6 位作者 Xueyan Wang Jingjing Li Guangbing Duan Junwen Wang Zhao Qin Shuchang Xu Ying Huang 《Neural Regeneration Research》 2026年第8期3641-3649,共9页
Aerobic exercise facilitates synaptic plasticity,thereby improving cognitive functions such as learning and memory.The 5-hydroxytryptamine system has been indicated in these processes.5-Hydroxytryptamine type 3 recept... Aerobic exercise facilitates synaptic plasticity,thereby improving cognitive functions such as learning and memory.The 5-hydroxytryptamine system has been indicated in these processes.5-Hydroxytryptamine type 3 receptors are necessary for exercise-induced hippocampal neurogenesis.Some antipsychotic drugs with 5-hydroxytryptamine type 3 receptor antagonistic properties may impede the amelioration of cognitive impairment and hippocampal plasticity induced by exercise.However,the mechanisms underlying the facilitation of synaptic plasticity by aerobic exercise have not yet been elucidated.In this study,we found that 5-hydroxytryptamine type 3 receptors played an important role in aerobic exercise-mediated improvement of hippocampal-dependent spatial and exploratory memory in mice.While 5-hydroxytryptamine type 3 receptors did not affect baseline neurogenesis in the hippocampal dentate gyrus,5-hydroxytryptamine type 3 receptors were required for aerobic exercise-induced neurogenesis and astrocyte proliferation in this region.In addition,5-hydroxytryptamine type 3 receptors were crucial for maintaining long-term potentiation in the CA1,dentate gyrus,and CA3 regions of the hippocampus.The long-term potentiation changes induced by aerobic exercise in sub-regions of the hippocampus were heterogeneous:5-hydroxytryptamine type 3 receptors were essential for aerobic exercise to enhance long-term potentiation in the CA3,but not the CA1 or dentate gyrus,regions of the hippocampus.Furthermore,aerobic exercise up-regulated 5-hydroxytryptamine type 3 receptor expression and increased brain-derived neurotrophic factor release in the hippocampus in a 5-hydroxytryptamine type 3 receptor-dependent manner.These results suggest that aerobic exercise increases hippocampal dentate gyrus neurogenesis and astrocyte proliferation via the up-regulation of 5-hydroxytryptamine type 3 receptors,leading to more brain-derived neurotrophic factor production and release from these cells,which results in long-term potentiation facilitation in the hippocampal CA3 region and help improve memory.Our findings provide insight into the mechanisms by which physical activity enhances memory and may have implications for improving memory through modulating 5-hydroxytryptamine type 3 receptor. 展开更多
关键词 5-HYDROXYTRYPTAMINE 5-hydroxytryptamine type 3 receptor aerobic exercise brain-derived neurotrophic factor exploratory memory hippocampus long-term potentiation NEUROGENESIS neuroglia proliferation spatial memory
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Synaptic mitochondria in aging and neurodegenerative diseases:Functional decline and vulnerability
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作者 Karina A.Cicali Angie K.Torres Cheril Tapia-Rojas 《Neural Regeneration Research》 2026年第6期2145-2152,共8页
Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A ... Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A crucial factor contributing to this decline is the dysfunction of mitochondria,particularly those located at synapses.Synaptic mitochondria are specialized organelles that produce the energy required for synaptic transmission but are also important for calcium homeostasis at these sites.In contrast,non-synaptic mitochondria primarily involve cellular metabolism and long-term energy supply.Both pools of mitochondria differ in their form,proteome,functionality,and cellular role.The proper functioning of synaptic mitochondria depends on processes such as mitochondrial dynamics,transport,and quality control.However,synaptic mitochondria are particularly vulnerable to age-associated damage,characterized by oxidative stress,impaired energy production,and calcium dysregulation.These changes compromise synaptic transmission,reducing synaptic activity and cognitive decline during aging.In the context of neurodegenerative diseases such as Alzheimer’s,Parkinson’s,and Huntington’s,the decline of synaptic mitochondrial function is even more pronounced.These diseases are marked by pathological protein accumulation,disrupted mitochondrial dynamics,and heightened oxidative stress,accelerating synaptic dysfunction and neuronal loss.Due to their specialized role and location,synaptic mitochondria are among the first organelles to exhibit dysfunction,underscoring their critical role in disease progression.This review delves into the main differences at structural and functional levels between synaptic and non-synaptic mitochondria,emphasizing the vulnerability of synaptic mitochondria to the aging process and neurodegeneration.These approaches highlight the potential of targeting synaptic mitochondria to mitigate age-associated cognitive impairment and synaptic degeneration.This review emphasizes the distinct vulnerabilities of hippocampal synaptic mitochondria,highlighting their essential role in sustaining brain function throughout life and their promise as therapeutic targets for safeguarding the cognitive capacities of people of advanced age. 展开更多
关键词 AGING HIPPOCAMPUS MEMORY MITOCHONDRIA synaptic mitochondria
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Tell Me About Your Hometown
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作者 Ruth Devlin 《空中英语教室(初级版.大家说英语)》 2026年第1期20-22,52,共4页
Your hometown is often a special place.It can be big or small.And it usually has an important place in your life and heart.You may not live there anymore.But you remember it well.Maybe you have warm feelings for your ... Your hometown is often a special place.It can be big or small.And it usually has an important place in your life and heart.You may not live there anymore.But you remember it well.Maybe you have warm feelings for your school,your friends and your neighbors there.You remember special places and fun times.There may be interesting museums or great sports teams in your hometown.You can tell people about them. 展开更多
关键词 HOMETOWN NEIGHBORS FRIENDS special places MUSEUMS memories sports teams school
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The multilayered identity of B cell memory
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作者 Vassilis Glaros Nimmy Francis Taras Kreslavsky 《Cellular & Molecular Immunology》 2026年第2期150-167,共18页
The distinctive feature of the adaptive immune system is its ability to generate immunological memory that can provide defense against subsequent infections.In the case of antibody-mediated immune responses,this memor... The distinctive feature of the adaptive immune system is its ability to generate immunological memory that can provide defense against subsequent infections.In the case of antibody-mediated immune responses,this memory comes in two cellular forms:plasma cells(PCs)and memory B cells(MBCs).PCs protect against reinfection by constitutively producing antibodies.The presence of a diverse pool of MBCs,which can expand and differentiate into PCs in secondary immune responses,is thought to be particularly important for defense against new pathogen variants.Recent studies have shown that the MBC compartment is far more heterogeneous than previously anticipated.This heterogeneity,among other factors,is shaped by their developmental pathway(germinal center(GC)vs non-GC-derived MBCs),the duration and strength of antigenic stimulation,anatomical and microanatomical localization,and the timing of generation in ontogeny.Combinations of these“layers”of MBC identities can define MBCs’properties and their fate in recall responses.Here,we review the mechanisms underlying MBC differentiation,maintenance,and reactivation and explore how the layered identity of MBCs contributes to the functions of these cells. 展开更多
关键词 B cell memory Humoral immune response Tissue-resident memory B cells
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Lignin-derived High-performance Near-infrared Light-responsive Shape Memory Polyurethanes for Biomedical Applications
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作者 Su-Yang Dai Jia-Yue Li +5 位作者 Ling-Chen Mao Dan-Hua Zhou Yu Zhang Zhi-Hua Gana Zhen-Bo Ning Yun-Feng Lu 《Chinese Journal of Polymer Science》 2026年第4期1090-1101,I0016,共13页
Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,whil... Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential. 展开更多
关键词 LIGNIN POLYURETHANE Shape memory polymers NIR light responsive POLYCAPROLACTONE
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Adiponectin as a potential mediator of the pro-cognitive effects of physical exercise on Alzheimer's disease
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作者 Hui-Hui Guo Hai-Ning Ou +5 位作者 Jia-Sui Yu Julia Macedo Rosa Douglas Affonso Formolo Tong Cheng Suk-Yu Yau Hector Wing Hong Tsang 《Neural Regeneration Research》 2026年第1期96-106,共11页
Alzheimer's disease is the primary cause of dementia and imposes a significant socioeconomic burden globally.Physical exercise,as an effective strategy for improving general health,has been largely reported for it... Alzheimer's disease is the primary cause of dementia and imposes a significant socioeconomic burden globally.Physical exercise,as an effective strategy for improving general health,has been largely reported for its effectiveness in slowing neurodegeneration and increasing brain functional plasticity,particularly in aging brains.However,the underlying mechanisms of exercise in cognitive aging remain largely unclear.Adiponectin,a cell-secreted protein hormone,has recently been found to regulate synaptic plasticity and mediate the antidepressant effects of physical exercise.Studies on the neuroprotective effects of adiponectin have revealed potential innovative treatments for Alzheimer's disease.Here,we reviewed the functions of adiponectin and its receptor in the brains of human and animal models of cognitive impairment.We summarized the role of adiponectin in Alzheimer's disease,focusing on its impact on energy metabolism,insulin resistance,and inflammation.We also discuss how exercise increases adiponectin secretion and its potential benefits for learning and memory.Finally,we highlight the latest research on chemical compounds that mimic exerciseenhanced secretion of adiponectin and its receptor in Alzheimer's disease. 展开更多
关键词 adiponectin receptor agonists ADIPONECTIN Alzheimer's disease amyloid-β HIPPOCAMPUS learning and memory physical exercise TAU
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Uniform Attractors for the Kirchhoff Type Suspension Bridge Equation with Nonlinear Damping and Memory Term
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作者 Ling XU Yanni WANG 《Journal of Mathematical Research with Applications》 2026年第1期71-86,共16页
The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and e... The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and existence of uniform attractor under some suitable assumptions on the nonlinear term g(u),the nonlinear damping f(u_(t))and the external force h(x,t).Specifically,the asymptotic compactness of the semigroup is verified by the energy reconstruction method. 展开更多
关键词 uniform attractor Kirchhoff type suspension bridge equation nonlinear damping memory term
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ResghostNet:Boosting GhostNet with Residual Connections and Adaptive-SE Blocks
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作者 Yuang Chen Yong Li +2 位作者 Fang Lin Shuhan Lv Jiaze Jiang 《Computers, Materials & Continua》 2026年第2期1524-1541,共18页
Aiming at the problem of potential information noise introduced during the generation of ghost feature maps in GhostNet,this paper proposes a novel lightweight neural network model called ResghostNet.This model constr... Aiming at the problem of potential information noise introduced during the generation of ghost feature maps in GhostNet,this paper proposes a novel lightweight neural network model called ResghostNet.This model constructs the Resghost Module by combining residual connections and Adaptive-SE Blocks,which enhances the quality of generated feature maps through direct propagation of original input information and selection of important channels before cheap operations.Specifically,ResghostNet introduces residual connections on the basis of the Ghost Module to optimize the information flow,and designs a weight self-attention mechanism combined with SE blocks to enhance feature expression capabilities in cheap operations.Experimental results on the ImageNet dataset show that,compared to GhostNet,ResghostNet achieves higher accuracy while reducing the number of parameters by 52%.Although the computational complexity increases,by optimizing the usage strategy of GPU cachememory,themodel’s inference speed becomes faster.The ResghostNet is optimized in terms of classification accuracy and the number of model parameters,and shows great potential in edge computing devices. 展开更多
关键词 Residual connections adaptive-SE blocks lightweight neural network GPU memory usage
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The intrinsic excitability of and autophagy protein expression levels in dentate gyrus ensembles regulate fear generalization
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作者 Qing Lin Tao Jin +5 位作者 Yang Yang Xutian Hou Ruyan Chen Lan Ma Xing Liu Feifei Wang 《Neural Regeneration Research》 2026年第7期3073-3082,共10页
The overgeneralization of fear is associated with psychiatric disorders and cognitive decline.Recent studies have shown that engram cells in the dorsal dentate gyrus are integrated into functionally heterogeneous ense... The overgeneralization of fear is associated with psychiatric disorders and cognitive decline.Recent studies have shown that engram cells in the dorsal dentate gyrus are integrated into functionally heterogeneous ensembles that are involved in contextual fear memory generalization and discrimination.However,the intracellular signals that promote fear generalization remain to be fully elucidated.In this study,we labeled and manipulated the c-Fos+and Npas4+ensembles in the dorsal dentate gyrus that are activated by contextual fear conditioning using a robust activity marking system.The results showed that increasing the excitability of Fos-dependent robust activity marking by overexpressing NaChBac or decreasing the excitability of Npas4-dependent robust activity marking by overexpressing Kir2.1 promoted fear memory generalization.Furthermore,CRISPR-mediated downregulation of the autophagy-related Atg5 or Atg7 genes in dorsal dentate gyrus neurons inhibited activation of c-Fos,but not Npas4.Knockdown of Atg5 or Atg7 in the Fos-dependent robust activity marking or Npas4-dependent robust activity marking ensemble led to an increase in neuronal excitability and a decrease in spine density in both ensembles.However,Atg7 knockdown in the Fos-dependent robust activity marking ensemble promoted memory generalization,while knockdown of Atg5 or Atg7 in the Npas4-dependent robust activity marking ensemble increased anxiety levels.These results contribute to our understanding of how the varying plasticity of memory engrams is involved in regulating fear memory generalization and anxiety. 展开更多
关键词 ANXIETY ATG7/5 C-FOS dendritic spine dentate gyrus intrinsic excitability memory generalization Npas4
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Optimization of UAV visual tracking based on structure-consistent modeling in complex environments
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作者 Zhang Qijia Qin Danyang Zhang Xiao 《High Technology Letters》 2026年第1期60-72,共13页
This paper investigates the challenges of structural inconsistency,matching accuracy degradation,and trajectory interruptions caused by high-speed motion,frequent occlusions,and appearance variations of unmanned aeria... This paper investigates the challenges of structural inconsistency,matching accuracy degradation,and trajectory interruptions caused by high-speed motion,frequent occlusions,and appearance variations of unmanned aerial vehicle(UAV) targets in low-altitude airspace.A novel UAV visual tracking method is proposed for dynamic structural distortions,with a focus on structural consistency modeling to improve system robustness in complex scenarios.Unlike prior methods such as STARK,which rely on spatio-temporal prediction,and KeepTrack,which emphasize template maintenance,our approach enforces structural-level consistency between historical and current features,thereby addressing UAV-specific issues of rapid maneuvering and environmental complexity.The proposed framework features a structure-aware architecture that incorporates dual complementary mechanisms serving as spatial completion and temporal restoration components.First,a multi-scale structure extraction module with adaptive anchor scheduling is developed to dynamically perceive spatial target shape and generate high-quality proposals.Second,a structural memory module is designed to reconstruct local regions by leveraging high-confidence historical structural representations,thereby maintaining spatiotemporal coherence across frames.Furthermore,a structural verification mechanism coupled with a meta-learning-driven re-identification strategy is introduced to detect abrupt structural distortions and adaptively update templates,significantly improving resilience against disturbances.Overall,the main contributions of this paper can be summarized as follows:(1) introducing structural consistency modeling into UAV visual tracking for the first time;(2) designing a unified framework that combines adaptive proposal generation,full-image matching,and re-identification under structural constraints;and(3) achieving state-of-the-art performance on the anti-UAV benchmark,highlighting the method's practical value in real-world UAV surveillance applications. 展开更多
关键词 adaptive anchor proposal meta updater temporal memory bank UAV tracking
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Effects of Temperature,Loading Frequency,Stress Amplitude,and Stress Ratio on the Low-Cycle Fatigue Behavior of FeMnSiCrNi Shape Memory Alloys
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作者 Bo Xu Beihai Huang +4 位作者 Sen Tang Xiang Xu Huabei Peng Chong Wang Qingyuan Wang 《Acta Mechanica Solida Sinica》 2026年第2期133-151,共19页
FeMnSi-based shape memory alloys(SMAs)have great applied potential to large-scale structures in civil engineering,especially as an aseismic structural material.Low-cycle fatigue performance is one of the most importan... FeMnSi-based shape memory alloys(SMAs)have great applied potential to large-scale structures in civil engineering,especially as an aseismic structural material.Low-cycle fatigue performance is one of the most important properties of FeMnSi-based SMA aseismic materials.However,the low-cycle fatigue behavior of such SMAs,especially the stress-controlled low-cycle fatigue behavior(with ratchetting effect),has not been clearly understood.In this work,the low-cycle fatigue behavior of the FeMnSiCrNi SMAs subjected to stress-controlled cyclic tension–compression loads is investigated,and the effects of temperature,loading frequency,stress amplitude,and stress ratio are addressed.By analyzing the cyclic stress–strain response,fatigue fracture surface morphology,dissipation energy,ratchetting strain,and equivalent damping ratio,the mechanisms behind the temperature-,loading frequency-,stress amplitude-,and stress ratio-dependent low-cycle fatigue behavior are discussed.The results show that the plasticity,martensitic transformation,and/or the ratchetting strain caused by their tension–compression asymmetry are the decisive factors affecting the low-cycle fatigue behavior of FeMnSiCrNi SMAs. 展开更多
关键词 FeMnSiCrNi shape memory alloy Low-cycle fatigue behavior TEMPERATURE Loading frequency Stress amplitude Stress ratio
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Attention-Enhanced ResNet-LSTM Model with Wind-Regime Clustering for Wind Speed Forecasting
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作者 Weiqi Mao Enbo Yu +1 位作者 Guoji Xu Xiaozhen Li 《Computer Modeling in Engineering & Sciences》 2026年第1期781-811,共31页
Accurate wind speed prediction is crucial for stabilizing power grids with high wind energy penetration.This study presents a novel machine learning model that integrates clustering,deep learning,and transfer learning... Accurate wind speed prediction is crucial for stabilizing power grids with high wind energy penetration.This study presents a novel machine learning model that integrates clustering,deep learning,and transfer learning to mitigate accuracy degradation in 24-h forecasting.Initially,an optimized DB-SCAN(Density-Based Spatial Clustering of Applications with Noise)algorithm clusters wind fields based on wind direction,probability density,and spectral features,enhancing physical interpretability and reducing training complexity.Subsequently,a ResNet(Residual Network)extracts multi-scale patterns from decomposed wind signals,while transfer learning adapts the backbone network across clusters,cutting training time by over 90%.Finally,a CBAM(Convolutional Block Attention Module)attention mechanism is employed to prioritize features for LSTM-based prediction.Tested on the 2015 Jena wind speed dataset,the model demonstrates superior accuracy and robustness compared to state-of-the-art baselines.Key innovations include:(a)Physics-informed clustering for interpretable wind regime classification;(b)Transfer learning with deep feature extraction,preserving accuracy while minimizing training time;and(c)On the 2016 Jena wind speed dataset,the model achieves MAPE(Mean Absolute Percentage Error)values of 16.82%and 18.02%for the Weibull-shaped and Gaussian-shaped wind speed clusters,respectively,demonstrating the model’s robust generalization capacity.This framework offers an efficient and effective solution for long-term wind forecasting. 展开更多
关键词 Wind speed prediction residual network transfer learning long short-term memory attention mechanism
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Optimization of 4D Printing Performance of Poly(lactic acid)/Thermoplastic Polyurethane Composites via Orthogonal Design and the Synergistic Effect of Crosslinking Agent-coupling Agent
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作者 Zhen Liu Bo Wang +5 位作者 Shi-Cheng Wei Wei Huang Yu-Jiang Wang Xin-Yang Wang Rui-Dong Shi Zheng-Jie Yang 《Chinese Journal of Polymer Science》 2026年第4期1069-1082,I0015,共15页
This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lacti... This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lactic acid)/thermoplastic polyurethane(PLA/TPU)matrix.Specifically,using a 70 wt%/30 wt%PLA/TPU matrix and an L_(9)(3^(2))orthogonal design,composites were evaluated via morphology,shape memory,mechanical tests,and multi-criteria analysis.Moderate DCP enhanced crosslinking,improving storage modulus and thermal stability,while excessive DCP caused brittleness.Furthermore,MAH-g-PE effectively improved interfacial compatibility,and its synergy with DCP was dosage-dependent.Consequently,Sample 5 achieved optimal performance,exhibiting uniform fracture morphology,a shape fixation rate of98.8%with the fastest recovery,and balanced strength-ductility.Multi-criteria analysis identified elongation at break and recovery time as the top contributing factors,with consistent rankings validated by Spearman analysis(ρ=0.833,p<0.01).In summary,adjusting DCP and MAH-g-PE contents effectively modulates the crosslinking structure and interfacial properties of PLA/TPU composites,providing a viable strategy for developing high-performance,tunable 4D printing materials. 展开更多
关键词 Shape memory Poly(lactic acid) Thermoplastic polyurethane Orthogonal experiment 4D printing
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Lycium barbarum glycopeptide reduces brain damage following ischemic stroke by inhibiting ferroptosis and oxidation
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作者 Wei Zhang Moushen Tang +6 位作者 Yujie Wang Yongxia Huang Zhexiong Yu Lihui Zhu Jian Wang Kwok-Fai So Yiwen Ruan 《Neural Regeneration Research》 2026年第7期2997-3006,共10页
Recent studies have indicated that stroke can lead to neuronal iron overload and lipid peroxidation.Lycium barbarum glycopeptide,which has a low molecular weight and potent antioxidant properties,may mitigate ferropto... Recent studies have indicated that stroke can lead to neuronal iron overload and lipid peroxidation.Lycium barbarum glycopeptide,which has a low molecular weight and potent antioxidant properties,may mitigate ferroptosis in stroke.We hypothesized that Lycium barbarum glycopeptide can effectively mitigate iron overload within ischemic neurons due to its robust antioxidant properties.The aims of this study were to investigate the effects of Lycium barbarum glycopeptide on ferroptotic damage following brain ischemia and explore the underlying mechanisms.A rat model of middle cerebral artery occlusion was established using the intraluminal filament method,and the rats were treated with Lycium barbarum glycopeptide for 7 consecutive days,beginning 24 hours after ischemia.Liproxstatin-1,a ferroptosis inhibitor,and Erastin,a ferroptosis activator,were used as controls.We found that treatment with Lycium barbarum glycopeptide resulted in significant reductions in infarct volume(as detected by triphenyltetrazolium chloride staining staining and magnetic resonance imaging)and neuronal death(as measured by Nissl staining),as well as improvements in sensory and motor functions in rats subjected to middle cerebral artery occlusion.Furthermore,treatment with Lycium barbarum glycopeptide alleviated anxiety and depression-like behaviors and improved memory.Additionally,Lycium barbarum glycopeptide effectively reduced the iron ion content in the ischemic penumbra of the cortex.Moreover,treatment with Lycium barbarum glycopeptide downregulated the expression of ferroptotic and oxidant proteins such as transferrin receptor 1,divalent metal transporter 1,and Acyl-CoA synthetase long-chain family member 4 and upregulated the expression of anti-ferroptotic and antioxidant proteins such as ferroportin 1,solute carrier family 7 member 11,glutathione,and glutathione peroxidase 4.However,these beneficial effects were reversed when ferroptosis was induced with the activator Erastin.Therefore,the positive effects of Lycium barbarum glycopeptide in ischemic stroke are likely mediated through activation of the anti-ferroptotic pathway and the antioxidative System Xc-glutathione-glutathione peroxidase 4 pathway.Overall,our findings highlight the potential use of Lycium barbarum glycopeptide as a neuroprotective agent targeting both ferroptosis and oxidation to decrease ischemic brain damage. 展开更多
关键词 ANTIOXIDATION ANXIETY cerebral ischemic depression inflammation iron overload Lycium barbarum glycopeptide magnetic resonance imaging memory neurological function NEUROPROTECTION
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An Agentic Artificial Intelligence Observer for Predictive Maintenance in Electrolysers
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作者 Abiodun Abiola Francisca Segura +1 位作者 JoséManuel Andújar Antonio Javier Barragán 《Computer Modeling in Engineering & Sciences》 2026年第3期718-749,共32页
This paper presents an artificial intelligence(AI)-based observer that combines fuzzy logic and neural networks to detect abnormalities in sensors embedded in an electrolyser.Electrolysers are hydrogen production plan... This paper presents an artificial intelligence(AI)-based observer that combines fuzzy logic and neural networks to detect abnormalities in sensors embedded in an electrolyser.Electrolysers are hydrogen production plants that require effective maintenance to guarantee suitable operation,prevent degradation,and avoid loss of efficiency.In this sense,predictive maintenance arises as one of the most advisable techniques for maintenance in electrolysers by using sensor data to predict potential abnormalities.However,if the sensor fails,there will be an incorrect forecasting of abnormalities.Among the different types of operational faults that sensors can present are drift-related faults,which are probably the most difficult to detect due to a slow but progressive loss of accuracy in measurements.Another problem with predictive maintenance is that it often requires enormous training data,which is not available at the early stage of plant operation.The developed fuzzy system is responsible for detecting faulty readings arising from drift sensor signals,while the neural network complements the function of the fuzzy system by predicting sensor signals when enough training data are available.The AI-based observer and the fuzzy rules are validated in an experimental case study with a 1 Nm^(3)/h electrolyser.The selected variables are electrolyser temperature and efficiency.Experimental results show that the rules of the fuzzy component of the AI-based observer guarantee an accuracy of±0.25 within the range of 0 to 1,and the neural network component predicted correct sensor values with a root mean square error(RMSE)as low as 0.0016.The authors’approach helps to determine drift faults without additional sensors or components installed in the plant. 展开更多
关键词 Electrolysis plant predictive maintenance artificial intelligence-based observer fuzzy system long short-term memory(LSTM) neural network
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Restoration of Extrasynaptic/Synaptic GABA_(A)R-α5 Localization Improves Sevoflurane-Induced Early Memory Impairment in Aged Mice
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作者 Mengxue Zhang Xiaokun Wang +5 位作者 Zhun Wang Jinpeng Dong Sixuan Wang Ying Dong Changyu Jiang Yiqing Yin 《Neuroscience Bulletin》 2026年第2期301-318,共18页
GABA_(A) receptors containingα5-subunits(GABA_(A)R-α5)cluster at both extrasynaptic and synaptic locations,interacting with the scaffold proteins radixin and gephyrin,respectively,and the re-localization of GABA_(A... GABA_(A) receptors containingα5-subunits(GABA_(A)R-α5)cluster at both extrasynaptic and synaptic locations,interacting with the scaffold proteins radixin and gephyrin,respectively,and the re-localization of GABA_(A)R-α5 influences GABAergic transmission.Here,we found that when early spatial memory deficits occurred in aged mice at 24 h after sevoflurane anesthesia,there was a re-localization of GABA_(A)R-α5 that enhanced tonic inhibition and reduced the decay kinetics of miniature inhibitory postsynaptic currents in the hippocampal CA1 region.Mechanistically,increased phosphorylation of radixin at threonine 564(Thr564)mediates the re-localization of GABA_(A)R-α5.Acute treatment with the selective extrasynaptic GABA_(A)R-α5 antagonist S44819 restored the GABA_(A)R-α5-mediated inhibitory currents by reversing radixin phosphorylation-dependent GABA_(A)R-α5 re-localization,then improved the sevoflurane-induced spatial memory impairment in aged mice.Our results suggest that the localization of GABA_(A)R-α5 altered by sevoflurane is linked to unbalanced GABAergic transmission,which induces early memory impairment in aged mice.Modulating the GABA_(A)R-α5 localization might be a novel strategy to improve memory after sevoflurane exposure. 展开更多
关键词 Aging SEVOFLURANE Memory GABA_(A)R-α5 HIPPOCAMPUS
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