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Oscillations of Magnetized Dust Grains in Plasma Sheath with Negative Ions

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Chinese Physics Letters 2007年第7期24卷 2003-2005页

作者：甘宝霞陈银华 Key laboratory of basic Plasma Physics and Department of Modern Physics University of Science and Technology of China Hefei 230026

The oscillations of a single magnetized dust grain in electronegative plasma sheath are investigated taking into account the existence of an external magnetic field. The influence of the content of negative ions and the magnetic field intensity on the properties of the dust vibration is analysed. The result shows that the existence of the negative ions in plasma reduces the dust oscillation frequency and drops the equilibrium position of dust, whereas the magnetic field raises the equilibrium position and also reduces the dust oscillation frequency on the condition considered.

关键词： PARTICLES

Electron Cyclotron Emission Imaging Observations of m/n=1/1 and Higher Harmonic Modes during Sawtooth Oscillation in ICRF Heating Plasma on EAST

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Chinese Physics Letters 2015年第6期32卷 111-114页

作者： AZA MHussain 高炳西刘万东谢锦林 the EAST Team Key laboratory of basic Plasma Physics Department of Modern PhysicsUniversity of Science and Technology of China

The m/n = 1/1 and its higher harmonic modes are observed in sawtooth oscillations by using the novel high- resolution 2D ECE imaging system on the experimental advanced superconducting Tokamak （EAST）. Higher harmonic modes are appearing for a short time during the crash phase of sawtooth oscillation in lower βp plasma, which is not the preferabie position in the poloidal cross section. These modes generate sharp pressure points on the inversion radius during the crash phase of sawtooth oscillation. Furthermore, reconnection events proceed in two distinctive phases. In the first phase, a small amount of heat is expelled through the weak reconnection while in the second phase the remaining large quantity of heat and particles emerged rapidly from the hot core to the peripheral region of the inversion radius. In addition, these harmonic modes are only found before and after the ICRF pulse, while in the ICRF pulse only the （1,1） mode exists in the sawtooth oscillation.

关键词： Electron Cyclotron Emission Imaging Observations of m/n

All-day solar power generation enabled by photo/thermoelectric conversion and thermal energy storage

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science China Chemistry 2025年

作者： Zijian Liu Chengzhi Chen Junda Liu Qi Sun Bingchen Huo Chunyu Du Guangming Chen College of Materials science and Engineering Shenzhen University

Thermoelectric materials hold promises for direct conversion of heat into electricity, making them viable power sources for electronic devices. However, their practical applications in diverse outdoor environment are hindered by limited and discontinuous electricity output. In this study, we propose an all-day solar power generator to achieve highly efficient and continuous electricity generation by harnessing the synergistic effects of photoelectric-thermoelectric conversion and latent thermal energy storage. The all-day solar power generator exhibits an average open-circuit voltage of 6.8 m V during daylight and a remaining 0.9 mV during nighttime. Importantly, the all-day solar power generator achieves dependable outdoor power supply for communication transmission in diverse environmental scenarios. Our research opens a new way for highly efficient and sustainable power generation.

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AAV mediated carboxyl terminus of Hsp70 interacting protein overexpression mitigates the cognitive and pathological phenotypes of APP/PS1 mice

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Neural Regeneration Research 2025年第1期20卷 253-264页

作者： Zhengwei Hu Jing Yang Shuo Zhang Mengjie Li Chunyan Zuo Chengyuan Mao Zhongxian Zhang Mibo Tang Changhe Shi Yuming Xu Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina Academy of Medical sciences of Zhengzhou University ZhengzhouHenan ProvinceChina NHC Key laboratory of Prevention and treatment of Cerebrovascular Diseases The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina Henan Key laboratory of Cerebrovascular Diseases The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina Institute of Neuroscience Zhengzhou UniversityZhengzhouHenan ProvinceChina Sino-British Research Centre for Molecular Oncology National Centre for International Research in Cell and Gene TherapySchool of Basic Medical SciencesAcademy of Medical SciencesZhengzhou UniversityZhengzhouHenan ProvinceChina Department of Gerontology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhouHenan ProvinceChina

The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control *** this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s *** used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse *** overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated *** also alleviated the concentration of microglia and astrocytes around *** APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin *** of HSP70 and HSP40,which have functional relevance to CHIP,were also *** nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of *** research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 ***,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.

关键词： adeno-associated virus Alzheimer’s disease APP/PS1 mice carboxyl terminus of Hsp70 interacting protein gene therapy

Local-contrastive-learning machine with both generalization and adversarial robustness: A statistical physics analysis

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 109-123页

作者： Mingshan Xie Yuchen Wang Haiping Huang PMI Lab School of Physics Sun Yat-sen University Guangdong Provincial Key laboratory of Magnetoelectric Physics and Devices Sun Yat-sen University

Distinct from human cognitive processing, deep neural networks trained by backpropagation can be easily fooled by adversarial examples. To design a semantically meaningful representation learning, we discard backpropagation, and instead, propose a local contrastive learning, where the representations for the inputs bearing the same label shrink(akin to boson) in hidden layers,while those of different labels repel(akin to fermion). This layer-wise learning is local in nature, being biologically plausible.A statistical mechanics analysis shows that the target fermion-pair-distance is a key parameter. Moreover, the application of this local contrastive learning to MNIST benchmark dataset demonstrates that the adversarial vulnerability of standard perceptron can be greatly mitigated by tuning the target distance, i.e., controlling the geometric separation of prototype manifolds.

关键词： machine learning statistical mechanics adversarial robustness neural networks

A method for extracting human gait series from accelerometer signals based on the ensemble empirical mode decomposition

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Chinese Physics B 2010年第5期19卷 592-601页

作者：符懋敬庄建军侯凤贞展庆波邵毅宁新宝 Key laboratory of Modern Acoustics Institute for Biomedical Electronic EngineeringDepartment of Electronic Science and EngineeringNanjing University Division of basic science China Pharmaceutical University

In this paper, the ensemble empirical mode decomposition （EEMD） is applied to analyse accelerometer signals collected during normal human walking. First, the self-adaptive feature of EEMD is utilised to decompose the ac- celerometer signals, thus sifting out several intrinsic mode functions （IMFs） at disparate scales. Then, gait series can be extracted through peak detection from the eigen IMF that best represents gait rhythmicity. Compared with the method based on the empirical mode decomposition （EMD）, the EEMD-based method has the following advantages： it remarkably improves the detection rate of peak values hidden in the original accelerometer signal, even when the signal is severely contaminated by the intermittent noises; this method effectively prevents the phenomenon of mode mixing found in the process of EMD. And a reasonable selection of parameters for the stop-filtering criteria can improve the calculation speed of the EEMD-based method. Meanwhile, the endpoint effect can be suppressed by using the auto regressive and moving average model to extend a short-time series in dual directions. The results suggest that EEMD is a powerful tool for extraction of gait rhythmicity and it also provides valuable clues for extracting eigen rhythm of other physiological signals.

关键词： ensemble empirical mode decomposition gait series peak detection intrinsic mode functions

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2025年第2期20卷 503-517页

作者： Qi Liu Jianye Xie Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi Department of Human Anatomy Histology and EmbryologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina Department of Neurology The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Department of General Practice The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic ***,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in ***,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic *** metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ***,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel ***-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in *** results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor *** findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

关键词： angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 neuroprotection self-assembling nanofiber hydrogel

An Obliquely Propagating Electromagnetic Lower-Hybrid-Drift Instability in Plasmas with Negative Ions

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Plasma science and Technology 2007年第4期9卷 388-393页

作者：王飞虎张宙陈银华黄凤 CAS Key laboratory of basic Plasma Physics Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026China

In this study, by employing a local fluid theory for warm plasma containing negative ions, an obliquely propagating electromagnetic instability in the lower hybrid frequency range driven by cross-field currents or relative drifts between electrons and ions was investigated. It is found that the growth rate of the lower-hybrid-drift instability （LHDI） can be controlled by appropriate selection of the propagation direction, the wave number and the relative population of the negative ions.

关键词： lower-hybrid-drift frequency instability negative ions local fluid theory

Lower-Hybrid Drift Instability in Modified Harris Current Sheet

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Plasma science and Technology 2008年第4期10卷 416-421页

作者：胡友俊杨维纮陈银华黄凤王飞虎张羽王栋 CAS Key laboratory of basic Plasma Physics Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Lower-hybrid drift instability （LHDI） in a Harris current sheet including a uniform background distribution is investigated in linear local kinetic theory. It is found that the introduction of a uniform background distribution reduces the growth rate and real frequency of LHDI at all wavelengths. Some physical explanations about the effects of the background distribution are provided.

关键词： lower-hybrid drift instability current sheet kinetic theory