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HD-YOLO:复杂场景下安全帽佩戴检测算法 被引量:2
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作者 邱云飞 腰瑞琳 +1 位作者 金海波 张嘉宁 《安全与环境学报》 北大核心 2025年第1期165-174,共10页
针对目标密集、有遮挡的复杂施工场景下安全帽佩戴检测存在漏检、误检的问题,提出了一种基于YOLOv8的HD-YOLO安全帽佩戴检测算法。首先,设计了GRC-C2f结构,使用多分支结构捕获多尺度特征,兼顾训练阶段的特征提取能力和推理阶段的计算效... 针对目标密集、有遮挡的复杂施工场景下安全帽佩戴检测存在漏检、误检的问题,提出了一种基于YOLOv8的HD-YOLO安全帽佩戴检测算法。首先,设计了GRC-C2f结构,使用多分支结构捕获多尺度特征,兼顾训练阶段的特征提取能力和推理阶段的计算效率。其次,设计了DSASF颈部结构,结合动态上采样和多尺度特征融合,精准识别和定位图像中的小目标,以提高检测性能。然后,引入Focal Modulation模块替换原有的快速空间金字塔池化(Spatial Pyramid Pooling-Fast,SPPF)结构模块,捕捉图像中的长距离依赖和上下文信息,聚焦于复杂背景中的目标。最后,采用空间增强注意力模块(Spatially Enhanced Attention Module,SEAM)解决小目标遮挡问题。试验结果表明,HD-YOLO算法在同一数据集上平均精度均值为81.8%,相比原始YOLOv8算法提高了5.0百分点。设计的HD-YOLO算法有效提高了复杂场景中佩戴安全帽的检测精度。 展开更多
关键词 安全社会工程 安全帽检测 YOLOv8算法 GRC-C2f模块 DSASF颈部结构 Focal Modulation模块 空间增强注意力模块
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基于改进TSM的船舶驾驶员行为识别方法
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作者 陈晨 魏月楠 +2 位作者 马枫 胡松涛 王腾飞 《交通信息与安全》 北大核心 2025年第1期120-129,140,共11页
船舶驾驶员不规范操作是诱发水上交通事故重要因素,设计1种实时船舶驾驶员行为检测方法意义重大。相比汽车驾驶、安防监控等,船舶驾驶舱环境更为复杂,存在无法兼顾多个船员、效率低下和准确率不高等问题。针对这种情况,研究了1种多目标... 船舶驾驶员不规范操作是诱发水上交通事故重要因素,设计1种实时船舶驾驶员行为检测方法意义重大。相比汽车驾驶、安防监控等,船舶驾驶舱环境更为复杂,存在无法兼顾多个船员、效率低下和准确率不高等问题。针对这种情况,研究了1种多目标跟踪和行为识别相结合的“两步式”多人行为识别方法。利用YoloV7与ByteTracker建立多目标跟踪器,形成单人的连续特征图。在单目标行为识别算法时间偏移模块(temporal shift module,TSM)的基础上,借助超采样、跨帧拼接等手段处理连续特征图,同时通过EfficientNet-B3与坐标注意力(coordinate attention,CA)模块输出高准确率的识别结果。研究建立了船舶驾驶舱行为数据集“SC-Action”,数据来自不同的船舶驾驶舱监控录像,包含常规行为以及违规行为共计2000例行为样本。在该数据集上对本文提出的模型进行迁移学习和消融实验,实验结果表明:提出的方法可实现3名驾驶员24帧/s的实时行为识别,识别速度和准确率均优于主流算法。在针对单人行为识别的测试中,方法在应用图像增强模块之后,相比基准TSM模型准确率提升了1.3%;结合注意力机制后,准确率进一步提升1.78%,达到了82.1%,而运算量仅增加0.1%。在多目标测试中,方法的实际推理速度和效果,也超越了该领域的主流方法如SlowFast,验证了其有效性。 展开更多
关键词 航行安全 行为识别 目标跟踪 注意力机制 temporal shift module
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Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process 被引量:1
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作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 EI 2025年第1期331-347,共17页
Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the p... Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the performanceof PV modules gradually declines due to internal degradation and external environmental factors.This cumulativedegradation impacts the overall reliability of photovoltaic power generation. This study addresses the complexdegradation process of PV modules by developing a two-stage Wiener process model. This approach accountsfor the distinct phases of degradation resulting from module aging and environmental influences. A powerdegradation model based on the two-stage Wiener process is constructed to describe individual differences inmodule degradation processes. To estimate the model parameters, a combination of the Expectation-Maximization(EM) algorithm and the Bayesian method is employed. Furthermore, the Schwarz Information Criterion (SIC) isutilized to identify critical change points in PV module degradation trajectories. To validate the universality andeffectiveness of the proposed method, a comparative analysis is conducted against other established life predictiontechniques for PV modules. 展开更多
关键词 Photovoltaic modules DEGRADATION stochastic processes lifetime prediction
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Substantially improved room-temperature tensile ductility in lightweight refractory Ti-V-Zr-Nb medium entropy alloys by tuning Ti and V content 被引量:2
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作者 Yuefei Jia Gengchen Li +6 位作者 Chang Ren Yongkun Mu Kang Sun Shiwei Wu Xilei Bian Yandong Jia Gang Wang 《Journal of Materials Science & Technology》 2025年第3期234-247,共14页
Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering impleme... Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering implementation,for instance in aerospace structural components.This work achieved a transfor-mative improvement of room-temperature tensile ductility in Ti-V-Zr-Nb MEAs with densities of 5.4-6.5 g/cm3,via ingenious composition modulation.Through the systematic co-adjustment of Ti and V contents,an intrinsic ductility mechanism was unveiled,manifested by a transition from predominant intergranular brittle fracture to pervasive ductile dimpled rupture.Notably,the modulated deformation mechanisms evolved from solitary slip toward collaborative multiple slip modes,without significantly compromising strength.Compared to equimolar Ti-V-Zr-Nb,a(Ti1.5V)3ZrNb composition demonstrated an impressive 360%improvement in elongation while sustaining a high yield strength of around 800 MPa.Increasing Ti and V not only purified the grain boundaries by reducing detrimental phases,but also tai-lored the deformation dislocation configurations.These insights expanded the applicability of lightweight HEAs to areas demanding combined high strength and ductility. 展开更多
关键词 DUCTILITY Lightweight high-entropy alloys High strength Composition modulation
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Spin-dependent amplitude and phase modulation with multifold interferences via single-layer diatomic all-silicon metasurfaces 被引量:2
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作者 Hui Li Chenhui Zhao +6 位作者 Jie Li Hang Xu Wenhui Xu Qi Tan Chunyu Song Yun Shen Jianquan Yao 《Opto-Electronic Science》 2025年第3期2-15,共14页
Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarizat... Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection. 展开更多
关键词 diatomic metasurface geometric phase complex amplitude modulation spin-selective
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Discoidin domain receptor 2 is an important modulator of BMP signaling during heterotopic bone formation 被引量:1
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作者 Fashuai Wu Chunxi Ge +4 位作者 Haichun Pan Yuanyuan Han Yuji Mishina Vesa Kaartinen Renny T.Franceschi 《Bone Research》 2025年第1期121-138,共18页
Bone morphogenetic proteins are essential for bone regeneration/fracture healing but can also induce heterotopic ossification(HO).Understanding accessory factors modulating BMP signaling would provide both a means of ... Bone morphogenetic proteins are essential for bone regeneration/fracture healing but can also induce heterotopic ossification(HO).Understanding accessory factors modulating BMP signaling would provide both a means of enhancing BMP-dependent regeneration while preventing HO.This study focuses on the ability of the collagen receptor,discoidin domain receptor 2(DDR2),to regulate BMP activity.As will be shown,induction of bone formation by subcutaneous BMP2 implants is severely compromised in Ddr2-deficient mice.In addition,Ddr2 deficiency attenuates HO in mice expressing the ACVR1 mutation associated with human fibrodysplasia ossificans progressiva.In cells migrating into BMP2 implants,DDR2 is co-expressed with GLI1,a skeletal stem cell marker,and DDR2/GLI1-positive cells participate in BMP2-induced bone formation where they contribute to chondrogenic and osteogenic lineages.Consistent with this distribution,conditional knockout of Ddr2 in Gli1-expressing cells inhibited bone formation to the same extent seen in globally Ddr2-deficient animals.This response was explained by selective inhibition of Gli1+cell proliferation without changes in apoptosis.The basis for this DDR2 requirement was explored further using bone marrow stromal cells.Although Ddr2 deficiency inhibited BMP2-dependent chondrocyte and osteoblast differentiation and in vivo,bone formation,early BMP responses including SMAD phosphorylation remained largely intact.Instead,Ddr2 deficiency reduced the nuclear/cytoplasmic ratio of the Hippo pathway intermediates,YAP and TAZ.This suggests that DDR2 regulates Hippo pathway-mediated responses to the collagen matrix,which subsequently affect BMP responsiveness.In summary,DDR2 is an important modulator of BMP signaling and a potential therapeutic target both for enhancing regeneration and treating HO. 展开更多
关键词 inhibited HEALING MODULATOR
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基于YOLOv8的轻量级无人机航拍小目标检测模型
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作者 陈奕衡 廉佐政 《齐齐哈尔大学学报(自然科学版)》 2025年第3期37-42,共6页
针对无人机携带计算资源受限的问题,提出一种轻量化的YOLOv8小目标检测模型。在主干网络中引入AKConv,通过灵活的卷积核减少不必要的参数;构建新的颈部网络SBN,通过GSConv降低计算开销,并利用双向信息传递机制,提高对不同尺度目标的检... 针对无人机携带计算资源受限的问题,提出一种轻量化的YOLOv8小目标检测模型。在主干网络中引入AKConv,通过灵活的卷积核减少不必要的参数;构建新的颈部网络SBN,通过GSConv降低计算开销,并利用双向信息传递机制,提高对不同尺度目标的检测精度;使用Focal Modulation替代原有的SPPF模块,增强模型在图像关键区域的注意力机制。结果表明,改进后的模型较YOLOv8,参数量降低30%,mAP50提高2.3%,同时相较于目标检测领域常用的一些模型,在轻量化和检测精度上均有更好的表现,证明了改进的有效性。 展开更多
关键词 小目标检测 YOLOv8 AKConv SBN Focal Modulation
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A K/Ka-band series Doherty CMOS power amplifier with distributed multi-step impedance inverting network 被引量:1
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作者 Xinyu Jiang Wei Deng +2 位作者 Junlong Gong Haikun Jia Baoyong Chi 《Journal of Semiconductors》 2025年第6期9-20,共12页
A two-way K/Ka-band series-Doherty PA(SDPA)with a distributed impedance inverting network(IIN)for millimeter wave applications is presented in this article.The proposed distributed IIN contributes to achieve wideband ... A two-way K/Ka-band series-Doherty PA(SDPA)with a distributed impedance inverting network(IIN)for millimeter wave applications is presented in this article.The proposed distributed IIN contributes to achieve wideband linear and power back-off(PBO)efficiency enhancement.Implemented in 65 nm bulk CMOS technology,this work realizes a measured 3 dB band-width of 15.5 GHz with 21.2 dB peak small-signal gain at 34.2 GHz.Under 1-V power supply,it achieves OP1dB over 13.4 dBm and Psat over 16 dBm between 21 to 30 GHz.The measured maximum Psat,OP1dB,peak/OP1dB/6dBPBO PAE results are 17.5,14.7 dBm,and 28.2%/23.2%/13.2%.Without digital pre-distortion(DPD)and equalization,EVMs are lower than-25.2 dB for 200 MHz 64-QAM signals.Besides,this work achieves-33.35,-23.52,and-20 dB EVMs for 100 MHz 256-QAM,600 MHz 64-QAM and 2 GHz 16-QAM signals at 27 GHz without DPD and equalization. 展开更多
关键词 Doherty PA load modulation BROADBAND transformer linear enhancement efficiency enhancement
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Bioinspired smart dual-layer hydrogels system with synchronous solar and thermal radiation modulation for energy-saving all-season temperature regulation 被引量:1
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作者 Meng-Chen Huang Chao-Hua Xue +8 位作者 Zhongxue Bai Jun Cheng Yong-Gang Wu Chao-Qun Ma Li Wan Long Xie Hui-Di Wang Bing-Ying Liu Xiao-Jing Guo 《Journal of Energy Chemistry》 2025年第2期175-190,I0005,共17页
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management... All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons. 展开更多
关键词 Thermochromic hydrogel Self-adaptive thermal management Radiative cooling Spectral modulation ENERGY-SAVING
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Ion-modulation optoelectronic neuromorphic devices:mechanisms,characteristics,and applications 被引量:1
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作者 Xiaohan Meng Runsheng Gao +1 位作者 Xiaojian Zhu Run-Wei Li 《Journal of Semiconductors》 2025年第2期24-36,共13页
The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorph... The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field. 展开更多
关键词 ion migration optoelectronic modulation optoelectronic device neuromorphic computing artificial vision system
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A novel carrier interleaved PWM method for four-level nested neutralpoint-clamped inverters 被引量:1
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作者 Wei Zhou Jupeng Pang +3 位作者 Mingzhe Wu Chao Wang Kui Wang Yongdong Li 《iEnergy》 2025年第1期65-76,共12页
The four-level nested neutral-point-clamped(4L-NNPC)inverter is a competitive topology among the various medium-voltage multilevel converters,and its main issue is flying-capacitor voltage unbalance.In this article,a ... The four-level nested neutral-point-clamped(4L-NNPC)inverter is a competitive topology among the various medium-voltage multilevel converters,and its main issue is flying-capacitor voltage unbalance.In this article,a novel carrier-interleaved pulse width modulation(CIPWM)method that satisfies the volt-sec balance principle is proposed with an advanced carrier distribution rule.By adopting the proposed CIPWM method,the redundant switching states of 4L-NNPC inverters can be evenly distributed into the output PWM waveform in each carrier period,and natural flying-capacitor voltage balance can be achieved.Furthermore,an active balancing strategy is also proposed to eliminate the voltage unbalance caused by nonideal factors,which is realized by simply adjusting the duty cycle and with no need to adjust the redundant switching states for 4L-NNPC inverters.The simulation and experimental results verify the effectiveness of the proposed CIPWM method and the flying-capacitor voltage balancing strategy. 展开更多
关键词 Multilevel converters capacitor voltage balance pulse width modulation
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Cation and anion modulation activates lattice oxygen for enhanced oxygen evolution 被引量:1
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作者 Mingxing Chen Zihe Du +8 位作者 Nian Liu Huijie Li Jing Qi Enbo Shangguan Jing Li Jiahao Cao Shujiao Yang Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 2025年第2期282-291,共10页
Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy... Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts. 展开更多
关键词 Oxygen evolution reaction ELECTROCATALYSIS Lattice oxygen mechanism High-valent metal species Cation and anion modulation
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Neuropeptide cholecystokinin:a key neuromodulator for hippocampal functions
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作者 Fengwen Huang Stephen Temitayo Bello 《Neural Regeneration Research》 SCIE CAS 2025年第7期1991-1992,共2页
Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodu... Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodulators shape its functions(Teixeira et al.,2018;Zhang et al.,2024).However,the landscape of neuromodulations in the hippocampal system remains poorly understood because most studies focus on classical monoamine neuromodulators,such as acetylcholine,serotonin,dopamine,and noradrenaline.The neuropeptides,comprising the most abundant neuromodulators in the central nervous system,play a pivotal role in neural information processing in the hippocampal system.Cholecystokinin(CCK),one of the most abundant neuropeptides,has been implicated in regulating various physiological and neurobiological statuses(Chen et al.,2019).CCK-A receptor(CCK-AR)and CCK-B receptors(CCK-BR)are two key receptors mediating the biological functions of CCK,both of which belong to class-A sevenfold transmembrane G protein-coupled receptors(Nishimura et al.,2015).CCK-AR preferentially reacts to sulfated CCK,whereas CCK-BR binds both CCK and gastrin with similar affinities(Ding et al.,2022).The expression patterns of CCK-AR and CCK-BR are distinct,implying that CCK has various functions in target regions.For instance,CCK-AR is widely expressed in the GI and brain subregions and is hence implicated in the control of digestive function and satiety regulation.Conversely,CCK-BR is abundantly and widely distributed in the central nervous system,which majorly regulates anxiety,learning,and memory(Ding et al.,2022).However,the roles of endogenous CCK and CCK receptors in regulating hippocampal function at electrophysiological and behavioral levels have received less attention. 展开更多
关键词 abundant FUNCTIONS MODULATOR
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Calcium-sensitive protein MLC1 as a possible modulator of the astrocyte functional state
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作者 Elena Ambrosini Angela Lanciotti Maria Stefania Brignone 《Neural Regeneration Research》 SCIE CAS 2025年第7期2008-2010,共3页
Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental... Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental stage to adult life.To maintain the optimal functionality of the brain,astroglial cells are particularly committed to reacting to every change in tissue homeostatic conditions,from mild modifications of the physiological environment,a process called astrocyte activation,to the more severe alterations occurring in pathological situations causing astrocyte reactivity or reactive astrogliosis(Escartin et al.,2021).During these reactive states,astrocytes mount an active,progressive response encompassing morphological,molecular,and interactional remodeling,leading to the acquisition of new functions and the loss of others,whose intensity,duration,and reversibility are dependent on the nature of the stimulus and regulated in a context-specific manner. 展开更多
关键词 alterations MODULATOR MAINTAIN
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Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics
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作者 Kaibiao Xi Jianzhe Guo +2 位作者 Mupeng Zheng Mankang Zhu Yudong Hou 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期87-101,共15页
High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,inclu... High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments. 展开更多
关键词 Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester
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Malicious Document Detection Based on GGE Visualization
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作者 Youhe Wang Yi Sun +1 位作者 Yujie Li Chuanqi Zhou 《Computers, Materials & Continua》 SCIE EI 2025年第1期1233-1254,共22页
With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers ... With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers has become particularly urgent.Currently,detection methods based on document structure and behavioral features encounter challenges in feature engineering,these methods not only have limited accuracy,but also consume large resources,and usually can only detect documents in specific formats,which lacks versatility and adaptability.To address such problems,this paper proposes a novel malicious document detection method-visualizing documents as GGE images(Grayscale,Grayscale matrix,Entropy).The GGE method visualizes the original byte sequence of the malicious document as a grayscale image,the information entropy sequence of the document as an entropy image,and at the same time,the grayscale level co-occurrence matrix and the texture and spatial information stored in it are converted into grayscale matrix image,and fuses the three types of images to get the GGE color image.The Convolutional Block Attention Module-EfficientNet-B0(CBAM-EfficientNet-B0)model is then used for classification,combining transfer learning and applying the pre-trained model on the ImageNet dataset to the feature extraction process of GGE images.As shown in the experimental results,the GGE method has superior performance compared with other methods,which is suitable for detecting malicious documents in different formats,and achieves an accuracy of 99.44%and 97.39%on Portable Document Format(PDF)and office datasets,respectively,and consumes less time during the detection process,which can be effectively applied to the task of detecting malicious documents in real-time. 展开更多
关键词 Malicious document VISUALIZATION EfficientNet-B0 convolutional block attention module GGE image
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Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery
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作者 Genfu Zhao Hang Ma +5 位作者 Conghui Zhang Yongxin Yang Shuyuan Yu Haiye Zhu Yongjiang Sun Hong Guo 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期456-471,共16页
Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal batteries.This study reports a high-... Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal batteries.This study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer interactions.Unlike other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal batteries.The introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based ligands.This is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)kinetics.Consequently,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system. 展开更多
关键词 Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery
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Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation
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作者 Younong Li Li Dan +2 位作者 Jing Peng Qidong Yang Fuqiang Yang 《Atmospheric and Oceanic Science Letters》 2025年第1期32-38,共7页
El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation an... El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures. 展开更多
关键词 Carbon variability ENSO modulation CMIP6 models
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Crystallization Modulation and Holistic Passivation Enables Efficient Two‑Terminal Perovskite/CuIn(Ga)Se_(2)Tandem Solar Cells
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作者 Cong Geng Kuanxiang Zhang +7 位作者 Changhua Wang Chung Hsien Wu Jiwen Jiang Fei Long Liyuan Han Qifeng Han Yi‑Bing Cheng Yong Peng 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期205-215,共11页
Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the ... Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device performances.In this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK crystals.In addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain boundaries.Meanwhile,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing recombination.As a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our knowledge.This validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells. 展开更多
关键词 PVK/CIGS TSCs Irregular rough surfaces Modulating the growth PVK/C60 interface recombination
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The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury
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作者 Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias +5 位作者 Iris K.Salgado Jose M.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.Miranda 《Neural Regeneration Research》 SCIE CAS 2025年第11期3317-3329,共13页
In addition to the loss of motor function,~60% of patients develop pain after spinal cord injury.The cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epice... In addition to the loss of motor function,~60% of patients develop pain after spinal cord injury.The cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic pain.Sprouting can lead to the formation of new connections triggering abnormal sensory transmission.The excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and excitotoxicity.Our previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator tamoxifen.In this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord injury.We hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant sprouting.Male and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical allodynia.Tamoxifen treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent effect.The expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on astrocytes.Female rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased excitatory amino acid transporter-2 expression compared with female rodents.Analyses of peptidergic(calcitonin gene-related peptide-α)and non-peptidergic(isolectin B4)fibers outgrowth in the dorsal horn after spinal cord injury showed an increased calcitonin gene-related peptide-α/isolectin B4 ratio in comparison with sham,suggesting increased receptive fields in the dorsal horn.Although the behavioral assay shows decreased allodynia in tamoxifen-treated female rats,this was not associated with overexpression of glutamate transporters or alterations in the dorsal horn laminae fibers at 28 days post-injury.Our findings provide new evidence of the sexually dimorphic expression of glutamate transporters in the spinal cord.The dimorphic expression revealed in this study provides a therapeutic opportunity for treating chronic pain,an area with a critical need for treatment. 展开更多
关键词 ALLODYNIA central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury TRAUMA
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