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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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Adaptive Fixed-Time Synchronization of Delayed Memristor-Based Neural Networks with Discontinuous Activations
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作者 Tianyuan Jia Xiangyong Chen +2 位作者 Xiurong Yao Feng Zhao Jianlong Qiu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期221-239,共19页
Fixed-time synchronization(FTS)of delayed memristor-based neural networks(MNNs)with discontinuous activations is studied in this paper.Both continuous and discontinuous activations are considered forMNNs.And the mixed... Fixed-time synchronization(FTS)of delayed memristor-based neural networks(MNNs)with discontinuous activations is studied in this paper.Both continuous and discontinuous activations are considered forMNNs.And the mixed delays which are closer to reality are taken into the system.Besides,two kinds of control schemes are proposed,including feedback and adaptive control strategies.Based on some lemmas,mathematical inequalities and the designed controllers,a few synchronization criteria are acquired.Moreover,the upper bound of settling time(ST)which is independent of the initial values is given.Finally,the feasibility of our theory is attested by simulation examples. 展开更多
关键词 Memristor-based neural networks fixed-time synchronization mixed delays discontinuous activations adaptive control
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Vascular dysfunctions and platelet activations by arsenic: two major contributing factors to cardiovascular disease
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作者 JH CHUNG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2006年第3期164-164,共1页
Arsenic in drinking water is a worldwide health problem that is associated with cardiovascular disease, but the cause is currently unknown. In order to examine whether arsenic affects vasomotor tone in blood vessels, ... Arsenic in drinking water is a worldwide health problem that is associated with cardiovascular disease, but the cause is currently unknown. In order to examine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on agonist-induced vasorelaxation and vasoconstriction using the isolated rat aortic rings in in vitro organ bath system. Treatment with inorganic arsenite (AsⅢ) inhibited acetylcholine-induced relaxation of aortic rings by inhibiting production of nitric oxide in endothelium. 展开更多
关键词 Vascular dysfunctions and platelet activations by arsenic two major contributing factors to cardiovascular disease
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Retrospective analysis of eFAST ultrasounds performed on trauma activations at an academic level-1 trauma center 被引量:9
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作者 Samantha Shwe Lauren Witchey +3 位作者 Shadi Lahham Ethan Kunstadt Inna Shniter John C.Fox 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2020年第1期12-17,共6页
BACKGROUND:Point-of-care ultrasound(POCUS)has become increasingly integrated into the practice of emergency medicine.A common application is the extended focused assessment with sonography in trauma(eFAST)exam.The Ame... BACKGROUND:Point-of-care ultrasound(POCUS)has become increasingly integrated into the practice of emergency medicine.A common application is the extended focused assessment with sonography in trauma(eFAST)exam.The American College of Emergency Physicians has guidelines regarding the scope of ultrasound in the emergency department and the appropriate documentation.The objective of this study was to conduct a review of performed,documented and billed eFAST ultrasounds on trauma activation patients.METHODS:This was a retrospective review of all trauma activation patients during a 10-month period at an academic level-one trauma center.A list comparing all trauma activations was crossreferenced with a list of all billed eFAST scans.Medical records were reviewed to determine whether an eFAST was indicated,performed,and appropriately documented.RESULTS:We found that 1,507 of 1,597 trauma patients had indications for eFAST,but 396(27%)of these patients did not have a billed eFAST.Of these 396 patients,87(22%)had documentation in the provider note that an eFAST was performed but there was no separate procedure note.The remaining 309(78%)did not have any documentation of the eFAST in the patient’s chart although an eFAST was recorded and reviewed during ultrasound quality assurance.CONCLUSION:A significant proportion of trauma patients had eFAST exams performed but were not documented or billed.Lack of documentation was multifactorial.Emergency ultrasound programs require appropriate reimbursement to support training,credentialing,equipment,quality assurance,and device maintenance.Our study demonstrates a significant absence of adequate documentation leading to potential revenue loss for an emergency ultrasound program. 展开更多
关键词 POINT-OF-CARE ultrasound Emergency medicine Focused assessment withsonography in TRAUMA TRAUMA activation BLUNT TRAUMA
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Preparation of Activated Carbon from Durian Rind with Difference Activations and Its Optimization 被引量:3
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作者 Pongsert Sriprom Warawut Krusong Pornsawan Assawasaengrat 《Journal of Renewable Materials》 SCIE EI 2021年第2期311-324,共14页
Durian rind wastes are an important raw material for activated carbon production due to their renewable sources and low-cost materials.The efficiency of increasing surface area and the quantity of oxygen groups on the... Durian rind wastes are an important raw material for activated carbon production due to their renewable sources and low-cost materials.The efficiency of increasing surface area and the quantity of oxygen groups on the surface of activated carbon were studied for the preparation of activated carbon.The preparation of activated carbon has been studied with the different methods as follows:activation by acid,activation by base,hydrothermal and activation by acid,and hydrothermal and activation by base.The results showed that hydrothermal and activation by acid had high iodine number which was chosen to determine the optimum condition for activated carbon preparation.The optimum condition for preparation of durian rind activated carbon was studied by Box-Behnken design.Solid/water ratio,solid/acid ratio and temperature were chosen as the important parameters for achieving the optimum reaction condition.The reaction products were analyzed by iodine number.Based on the results,the optimum condition for preparation of durian rind activated carbon was predicted using RSM.The maximum iodine number of 626.47 mg/g was expected at the optimum condition:solid/water ratio(1:175,g/mL),solid/acid ratio(1:23,g/mL)and temperature(500℃).The preparation of durian rind activated carbon at the optimal condition was carried;the percentages of iodine number achieved(666.73±6 mg/g)were close to the maximum predicted value(666.73 mg/g),thus verifying the model.At the optimum condition,the functional group on surface of durian rind activated carbon was characterized by FT-IR.The result showed that the oxygen content on surface was increased in the form of carbonyl and sulfonyl group. 展开更多
关键词 Durian rind activated carbon HYDROTHERMAL iodine number
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FIXED/PREASSIGNED-TIME SYNCHRONIZATION OF QUATERNION-VALUED NEURAL NETWORKS INVOLVING DELAYS AND DISCONTINUOUS ACTIVATIONS: A DIRECT APPROACH 被引量:1
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作者 魏琬璐 胡成 +1 位作者 于娟 蒋海军 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1439-1461,共23页
The fixed-time synchronization and preassigned-time synchronization are investigated for a class of quaternion-valued neural networks with time-varying delays and discontinuous activation functions. Unlike previous ef... The fixed-time synchronization and preassigned-time synchronization are investigated for a class of quaternion-valued neural networks with time-varying delays and discontinuous activation functions. Unlike previous efforts that employed separation analysis and the real-valued control design, based on the quaternion-valued signum function and several related properties, a direct analytical method is proposed here and the quaternion-valued controllers are designed in order to discuss the fixed-time synchronization for the relevant quaternion-valued neural networks. In addition, the preassigned-time synchronization is investigated based on a quaternion-valued control design, where the synchronization time is preassigned and the control gains are finite. Compared with existing results, the direct method without separation developed in this article is beneficial in terms of simplifying theoretical analysis, and the proposed quaternion-valued control schemes are simpler and more effective than the traditional design, which adds four real-valued controllers. Finally, two numerical examples are given in order to support the theoretical results. 展开更多
关键词 fixed-time synchronization preassigned-time synchronization quaternion-valued neural networks discontinuous activation direct analysis method
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In situ formation of Zr_2Al_3C_4/Al_2O_3 composites by combustion synthesis with PTFE and thermal activations 被引量:1
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作者 Chun-liang YEH Yi-Chang CHEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第10期2011-2016,共6页
Preparation of Zr2Al3C4-Al2O3 in situ composites was investigated by self-propagating high-temperature synthesis(SHS)involving both aluminothermic reduction of ZrO2 and chemical activation of PTFE(Teflon).The starting... Preparation of Zr2Al3C4-Al2O3 in situ composites was investigated by self-propagating high-temperature synthesis(SHS)involving both aluminothermic reduction of ZrO2 and chemical activation of PTFE(Teflon).The starting materials included ZrO2,Al,carbon black and PTFE.In addition to the conventional SHS method,the experiments were conducted by a chemical-oven SHS(COSHS)route to thermally assist the synthesis reaction.The threshold amount of 2%(mass fraction)PTFE was required to induce self-sustaining combustion.When the conventional SHS scheme was utilized,due to low combustion temperatures between 1152 and 1272°C and insufficient reaction time,the dominant carbide forming in the composite was ZrC instead of Zr2Al3C4.On the other hand,the COSHS technique increased the combustion temperature of the reactant compact to about 1576°C,lengthened the high-temperature duration for the reaction,and prevented Al vapor from escaping away.As a consequence,Zr2Al3C4-Al2O3 composites with a small amount of Zr3Al3C5 were obtained.The microstructure of the COSHS-derived product showed that plate-like Zr2Al3C4 grains were about 2μm in thickness and 10-30μm in length,and most of them were closely stacked into a laminated configuration. 展开更多
关键词 Zr2Al3C4 combustion synthesis PTFE activation chemical-oven SHS aluminothermic reduction
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Dry reforming of methane on doped Ni nanoparticles:Featureassisted optimizations and ranking of doping metals for direct activations of CH_(4) and CO_(2) 被引量:2
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作者 Shiru Lin Jean-Baptiste Tristan +1 位作者 Yang Wang Junwei Lucas Bao 《Nano Research》 SCIE EI CSCD 2022年第10期9670-9682,共13页
As a vital energy resource and raw material for many industrial products,syngas(CO and H_(2))is of great significance.Dry reforming of methane(DRM)is an important approach to producing syngas(with a hydrogen-to-carbon... As a vital energy resource and raw material for many industrial products,syngas(CO and H_(2))is of great significance.Dry reforming of methane(DRM)is an important approach to producing syngas(with a hydrogen-to-carbon-monoxide ratio of 1:1 in principle)from methane and carbon dioxide,with a lower operational cost as compared to other reforming techniques.However,many pure metallic catalysts used in DRM face deactivation issues due to coke formation or sintering of the metal particles.A systematic search for highly efficient metallic catalysts,which reduce the reaction barriers for the rate-determining steps and resist carbon deposition,is urgently needed.Nickel is a typical low-cost transition metal for activating the C–H bond in methane.In this work,we applied a two-step workflow to search for nickel-based bimetallic catalysts with doping metals M(M-Ni)by combining density functional theory(DFT)calculations and machine learning(ML).We focus on the two critical steps in DRM—CH_(4) and CO_(2) direct activations.We used DFT and slab models for the Ni(111)facet to explore the relevant reaction pathways and constructed a data set containing structural and energetic information for representative M-Ni systems.We used this dataset to train ML models with chemical-knowledge-based features and predicted CH_(4) and CO_(2) dissociation energies and barriers,which revealed the composition–activity relationships of the bimetallic catalysts.We also used these models to rank the predicted catalytic performance of candidate systems to demonstrate the applicability of ML for catalyst screening.We emphasized that ML ranking models would be more valuable than regression models in high-throughput screenings.Finally,we used our trained model to screen 12 unexplored M-Ni systems and showed that the DFT-computed energies and barriers are very close to the ML-predicted values for top candidates,validating the robustness of the trained model. 展开更多
关键词 Ni-based bimetallic catalysts dry reforming of methane syngas production CH_(4)and CO_(2)direct activations ranking model
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Overexpression of the inwardly rectifying potassium channel Kir4.1 or Kir4.1 Tyr^(9)Asp in Müller cells exerts neuroprotective effects in an experimental glaucoma model 被引量:1
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作者 Fang Li Zhen Li +6 位作者 Shuying Li Hong Zhou Yunhui Guo Yongchen Wang Bo Lei Yanying Miao Zhongfeng Wang 《Neural Regeneration Research》 2026年第4期1628-1640,共13页
Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apopt... Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma. 展开更多
关键词 apoptosis chronic ocular hypertension glial cell activation Kir4.1 overexpression Kir4.1 Tyr^(9)Asp mutation microglia Müller cells NEUROINFLAMMATION neuroprotection retinal ganglion cells
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Hot Compression Deformation Behavior and Processing Maps of Mg-Zn-Mn(-Sn)-Ca Alloy
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作者 Chen Xia Zhu Yulong +2 位作者 Liu Quanyi Zhang Dingfei Pan Fusheng 《稀有金属材料与工程》 北大核心 2026年第3期627-635,共9页
The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from... The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from 0.001 s^(-1) to 1 s^(-1).The results show that the addition of Sn promotes dynamic recrystallization(DRX),and CaMgSn phases can act as nucleation sites during the compression deformation.Flow stress increases with increasing the strain rate and decreasing the temperature.Both the ZM61-0.5Ca and ZMT612-0.5Ca alloys exhibit obvious DRX characteristics.CaMgSn phases can effectively inhibit dislocation motion with the addition of Sn,thus increasing the peak fl ow stress of the alloy.The addition of Sn increases the hot deformation activation energy of the ZM61-0.5Ca alloy from 199.654 kJ/mol to 276.649 kJ/mol,thus improving the thermal stability of the alloy.For the ZMT612-0.5Ca alloy,the optimal hot deformation parameters are determined to be a deformation temperature range of 350–400℃and a strain rate range of 0.001–0.01 s^(-1). 展开更多
关键词 hot deformation constitutive equation processing map deformation activation energy magnesium alloy
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Health Phys.Abstracts,Volume 129,Number 4
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《辐射防护》 北大核心 2026年第1期87-91,共5页
Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,... Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,and Wei-hao Qin1(1.National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing,100088,China.) 展开更多
关键词 nuclear medicine workers health physics carbon cartridge internal dose assessment analysis method I activity
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Prescribed-Time Active Disturbance Rejection Control for Electromagnetic Formation Flight Under Model Uncertainties and Disturbances
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作者 SHEN Xixi MENG Bin HU Jiangping 《空间控制技术与应用(中英文)》 北大核心 2026年第1期94-102,共9页
This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ... This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller. 展开更多
关键词 electromagnetic formation prescribed time active disturbance rejection control output feedback control
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Mechanism of enhancing NH_(3)-SCR performance of Mn-Ce/AC catalyst by the structure regulation of activated carbon with calcite in coal
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作者 NIU Jian LI Yuhang +4 位作者 BAI Baofeng WEN Chaolu LI Linbo ZHANG Huirong GUO Shaoqing 《燃料化学学报(中英文)》 北大核心 2026年第1期69-79,共11页
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ... To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced. 展开更多
关键词 CALCITE activated carbon structure Mn-Ce/AC catalyst NH_(3)-SCR performance
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Comprehensive review of the pharmacological potential of Passiflora incarnata L.:neuropsychiatric,antioxidant,antimicrobial,and anticancer activities
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作者 Balasubramanian Deepika Koyeli Girigoswami 《Traditional Medicine Research》 2026年第4期11-26,共16页
Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive com... Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive compounds such as flavonoids and alkaloids,which influence multiple biological pathways.This review aims to summarise and critically analyse recent findings on the pharmacological properties of Passiflora incarnata L.,focusing on its neuropsychiatric,antioxidant,antimicrobial,and anticancer activities.A targeted literature search was conducted in PubMed,Scopus,Web of Science,and Google Scholar for peer-reviewed publications between 2000 to 2025.Relevant articles were screened,and a more appropriate article related to the objective of the review was selected.Some classical papers are also cited as per the requirement of the topic.Passiflora incarnata L.showed multifunctional medicinal properties with various applications in neuropsychiatry,oxidative stress management,antimicrobial agent,and as an anticancer agent.The U.S.Food and Drug Administration categorizes passionflower extracts as“generally recognized as safe”.However,most evidence remains preclinical,with methodological variation limiting generalisation.Standardised formulation,robust clinical trials,and in-depth in vivo studies are essential to establish its therapeutic relevance and safety in modern medicine. 展开更多
关键词 Passiflora incarnata L ANTI-DEPRESSANT antioxidant activity antimicrobial activity anti-anxiety activity anticancer activity
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Navigating physical activity research in complex terrains:Reflections on the challenges,opportunities,and future directions
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作者 Ding Ding 《Journal of Sport and Health Science》 2026年第3期3-5,共3页
In 2025,I had the honor of delivering keynote speeches at the conferences of the International Society for Diet and Activity Methods in Toronto,Canada,and the International Society of Behavioural Nutrition and Physica... In 2025,I had the honor of delivering keynote speeches at the conferences of the International Society for Diet and Activity Methods in Toronto,Canada,and the International Society of Behavioural Nutrition and Physical Activity in Auckland,Aotearoa,New Zealand.These opportunities prompted deep reflection on scientific research in general,and on physical activity and health research specifically. 展开更多
关键词 scientific research complex terrains future directions diet activity methods research challenges physical activity behavioural nutrition physical activity
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An Overview of Drag Reduction Methods in Road Cars
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作者 Umberto Ravelli Silvia Ravelli 《Fluid Dynamics & Materials Processing》 2026年第2期1-41,共41页
Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection... Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection of studies was presented to focus on the most important aerodynamic features of the flow around realistic car body shapes.Then,the discussion was organized around three pillars related to passive flow control,active flow control and active aerodynamics.Both experimental and numerical investigations were included to provide a comprehensive overview.A clear distinction was made between simplified and realistic car models,as well as production vehicles(within the limits of restricted access information).Moreover,a short essay was dedicated to electric vehicles,for which aerodynamics matters,especially at highway speeds.Last,the impact of aerodynamic principles on the design of current and future vehicle fleet was assessed,honestly admitting that recent market trends must be reversed to turn decarbonization goals into reality and damp the effects of global warming. 展开更多
关键词 Road cars AERODYNAMICS drag coefficient passive flowcontrol active flowcontrol active aerodynamics
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Influence of Phenological Stage on the Volatile Content and Biological Properties of Origanum elongatum Essential Oil
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作者 Amine Batbat Khaoula Habbadi +6 位作者 Mohamed Jeddi Samiah Hamad Al-Mijalli Hanae Naceiri Mrabti Fahad M.Alshabrmi Naif Hesham Moursi Hassane Greche Naoufal El Hachlafi 《Phyton-International Journal of Experimental Botany》 2026年第1期203-217,共15页
Origanum elongatum(OE)is an aromatic,medicinal plant endemic to Morocco that is widely used in traditional medicine due to its biological properties.This study aimed to elucidate the chemical composition of the essent... Origanum elongatum(OE)is an aromatic,medicinal plant endemic to Morocco that is widely used in traditional medicine due to its biological properties.This study aimed to elucidate the chemical composition of the essential oil(EO)obtained from O.elongatum(OEEO)at three stages of its life cycle,including vegetative stage(OEEO-VS),flowering stage(OEEO-FS),and post-flowering(OEEO-PFS),as well as to evaluate its biological and antiradical characteristics.The chemical analysis of the essential oil was conducted using gas chromatography-mass spectrometry(GC-MS).The antibacterial activity was evaluated in vitro through distinct methodologies,namely,disc diffusion and microatmosphere assay;subsequently,the minimum inhibitory concentration(MIC)was then determined.The antioxidant potential was also measured by using the DPPH and FRAP assays.The GC-MS revealed the predominant of p-cymene(26.83%_31.45%),γ-terpinene(8.46%_26.95%),thymol(13%_29.54%),and carvacrol(20.25%_37.26%),in all three samples,with notable variations according to the phenological stage of the samples.The EOs extracted at three phenological stages demonstrated notable antibacterial efficacy against all the phytopathogen tested.The MICs for Erwinia amylovora exhibited a range of 6.25 and 250μg/mL.However,for Agrobacterium tumefaciens C58 and Allorhizobium vitis S4,the MICs spanned 125 and 250μg/mL.In the DPPH test,the IC50 values were 168.25±1.14,147.01±0.78,and 132.01±2.06μg/mL for EOs derived from the vegetative,flowering,and post-flowering period,respectively.In the FRAP test,the EC50 values were 164.22±1.04,215.73±1.48,and 184.06±0.95μg/mL for the same stages.The findings offer promising prospects for the phytochemical development,demonstrating how the phenological stage significantly influences the therapeutic and biotechnological potential of O.elongatum.This has the potential to open up new avenues of research in the pharmaceutical,agronomic,and environmental fields. 展开更多
关键词 Origanum elongatum phenological stage chemical composition antioxidant activity antibacterial activity bioactive compounds plant development chemotype variation
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Hydroalcoholic Extracts of Achillea spp.from Greece:A Study on Phenolic Content and Their Biological Activities
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作者 Olga S.Tsiftsoglou Vladimir Mihailovic +4 位作者 Nikola Sreckovic Jelena S.Katanic Stankovic Kyriakos Michail Dimitriadis Michalis K.Stefanakis Diamanto Lazari 《Phyton-International Journal of Experimental Botany》 2026年第1期34-48,共15页
Achillea species are known for their healing properties since ancient times.There is extensive literature on their pharmacological action due to their bioactive compounds.The present study aimed to investigate the ant... Achillea species are known for their healing properties since ancient times.There is extensive literature on their pharmacological action due to their bioactive compounds.The present study aimed to investigate the antioxidant and antimicrobial effects of hydroalcoholic extracts from the inflorescences and leaves of the species Achillea crithmifolia Waldst.and Kit.,A.grandifolia Friv.and A.millefolium L.The phytochemical profiles of all extracts were evaluated both by NMR spectroscopy and LC-MS analysis,and the results were consistent with the spectrophotometrically determined total phenolic(TP:125.42-191.98 mg/g)and total flavonoid(TF:47.34-180.02 mg/g)contents.All the extracts were tested for their antioxidant activity using DPPH and ABTS•+radical scavenging assay,as well as ferrous ion chelating ability and reducing power tests.All the extracts showed moderate antioxidant activity,compared to the reference substance BHT.Additionally,the antibacterial activity of the extracts was evaluated against major food-borne pathogens,showing moderate antimicrobial effects. 展开更多
关键词 Achillea spp. phenolics antioxidant activity antibacterial activity
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Design,synthesis,and biological evaluation of 2-(benzylsulfonyl)-5-(2-methoxypyridin-4-yl)-1,3,4-oxadiazole derivatives as novel herbicides
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作者 Sheng Yan Chujian Ma +5 位作者 Lamei Wu Changsheng Ma Yingying Wang Dingfeng Luo Zuren Li Zhijun Dai 《Advanced Agrochem》 2026年第1期25-32,共8页
To develop herbicides with a novel mechanism of action,a series of 1,3,4-oxadiazolpyridine derivatives were designed and synthesized based on active substructure splicing and structure optimization.These derivatives(5... To develop herbicides with a novel mechanism of action,a series of 1,3,4-oxadiazolpyridine derivatives were designed and synthesized based on active substructure splicing and structure optimization.These derivatives(5aa-5bd)were characterized by their melting points,^(1)H and^(13)C nuclear magnetic resonance spectroscopy,and high-resolution mass spectrometry.The configuration of 5 al was determined using single-crystal X-ray diffraction.Additionally,5 al exhibited excellent herbicidal activity at a dosage of 75 g/hm^(2),showing an EC 50 of 4.03 g/hm^(2)against both E.crus-galli and quinclorac-resistant E.crus-galli.At a dosage of 375 g/hm 2,5 al was safe for application on rice and sorghum and showed low toxicity(>200μg/g)towards Apis mellifera.After treatment with 5 al,the lamellae of the chloroplast grana of barnyard grass leaves were stacked disorderly and arranged loosely,and some thylakoids were broken,as observed by transmission electron microscopy.Transcriptomics analysis of E.crus-galli revealed that 5 al affects the defense response,membranes,plasma membranes,and chloroplasts of differentially expressed genes,which alter membrane permeability and energy metabolism,potentially leading to plant death.Thus,we successfully developed a novel molecular scaffold with a new mechanism of action that exhibits herbicidal activity against resistant E.crus-galli.Therefore,further development of lead herbicides based on this scaffold is required. 展开更多
关键词 Active substructure splicing Herbicidal activity Resistant barnyardgrass Transcriptomics.structure optimization
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