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Science China Technological Sciences 2025年

作者： Junyu HU Yourui TAO Shanhu LI xu HAN College of Mechanical and Vehicle Engineering Hunan University State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology

To enhance the tip positioning accuracy and robustness against disturbances of linear colocated motion systems, a novel composite feedforward (COMFF) control with Bi-Loop iterative feedforward tuning (IFFT) is proposed. The tip positioning error consists of the coupled tip residual vibration and linear motor tracking error. Given the influence of nonlinear friction and load flexibility, the topology of COMFF is designed as decoupled structures so that COMFF can suppress the tip residual vibration and compensate for the linear motor tracking error compatibly. Furthermore, Bi-Loop IFFT is built to improve the robustness of COMFF in high-precision motor tracking performance. In the state space of the linear motor tracking error based on the projection theorem, two loops are performed in parallel along the iteration direction. One is the P-type iteration loop that drives linear motor tracking errors to converge to the zero state. The other is the observation loop constructed by the recursive least square with forgetting factors to accelerate the P-type iteration loop. Driven by the P-type iteration loop with the aid of the observation loop, the proposed COMFF is integrated with fast convergence and high robustness when confronted with model disturbances. The effectiveness of the proposed COMFF combined with Bi-Loop IFFT is validated by experiments.

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Effects of mesoscale gravity waves on sporadic E simulated by a one-dimensional dynamic model

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Earth and Planetary Physics 2025年第1期9卷 1-9页

作者： xu Zhou ZeZhong Li XinAn Yue LiBo Liu Key Laboratory of Earth and Planetary Physics/Heilongjiang Mohe National Geophysical Observatory/Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences(CAS)Beijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Comparative Planetology/CAS Key Laboratory of Geospace Environment/Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China

In addition to being driven by tidal winds,the sporadic E(Es)layers are modulated by gravity waves(GWs),although the effects are not yet comprehensively *** this article,we discuss the effects of mesoscale GWs on the Es layers determined by using a newly developed model,MISE-1D(one-dimensional Model of Ionospheric Sporadic E),with low numerical dissipation and high *** by the wind fields resolved by the high-resolution version of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension(WACCM-X),the MISE-1D simulation revealed that GWs significantly influence the evolution of the Es layer above 100 km but have a very limited effect at lower *** effects of GWs are diverse and complex,generally including the generation of fluctuating wavelike structures on the Es layer with frequencies similar to those of the *** mesoscale GWs can also cause increases in the density of Es layers,or they can disperse or diffuse the Es layers and increase their *** addition,the presence of GWs is a key factor in sustaining the Es layers in some cases.

关键词： sporadic E ion tidal layer gravity waves numerical simulation

Knowledge Representation and Reasoning for Complex Time Expression in Clinical Text

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Data Intelligence 2022年第3期4卷 573-598页

作者： Danyang Hu Meng Wang feng Gao Fangfang xu Jinguang gu School of Computer Science and Technology Wuhan University of Science and TechnologyWuhan 430065China Key Laboratory of Rich-Media Knowledge Organization and Service of Digital Publishing Content National Press and Publication Administration of the People’s Republic of ChinaBeijing 10038China Institute of Big Data Science and Engineering Wuhan University of Science and TechnologyWuhan 430065China

Temporal information is pervasive and crucial in medical records and other clinical text,as it formulates the development process of medical conditions and is vital for clinical decision ***,providing a holistic knowledge representation and reasoning framework for various time expressions in the clinical text is *** order to capture complex temporal semantics in clinical text,we propose a novel Clinical Time Ontology(CTO)as an extension from OWL *** specifically,we identified eight timerelated problems in clinical text and created 11 core temporal classes to conceptualize the fuzzy time,cyclic time,irregular time,negations and other complex aspects of clinical ***,we extended Allen’s and TEO’s temporal relations and defined the relation concept description between complex and simple ***,we provided a formulaic and graphical presentation of complex time and complex time *** carried out empirical study on the expressiveness and usability of CTO using real-world healthcare ***,experiment results demonstrate that CTO could faithfully represent and reason over 93%of the temporal expressions,and it can cover a wider range of time-related classes in clinical domain.

关键词： Clinical text Temporal ontology Temporal relations OWL Negation of temporal relation

Oral microbiomes： more and more importance in oral cavity and whole body

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Protein & Cell 2018年第5期9卷 488-500页

作者： Lu Gao Tiansong xu Gang Huang Song Jiang Yan gu feng Chen Central Laboratory Peking University Hospital of Stomatology Beijing 100081 China Department of Orthodontics Peking University Hospital of Stomatology Beijing 100081 China

Microbes appear in every corner of human life, and microbes affect every aspect of human life. The human oral cavity contains a number of different habitats. Synergy and interaction of variable oral microorganisms help human body against invasion of undesirable stim- ulation outside. However, imbalance of microbial flora contributes to oral diseases and systemic diseases. Oral microbiomes play an important role in the human microbial community and human health. The use of recently developed molecular methods has greatly expanded our knowledge of the composition and function of the oral microbiome in health and disease. Studies in oral microbiomes and their interactions with microbiomes in variable body sites and variable health condition are critical in our cognition of our body and how to make effect on human health improvement.

关键词： oral microbiomes human health oraldiseases systematic diseases

Different types of drug abusers prefrontal cortex activation patterns and based on machine-learning classification

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Journal of Innovative Optical Health Sciences 2022年第2期15卷 83-92页

作者： Banghua Yang xuelin gu Shouwei Gao Lin feng Yan Ding xu Wen Wang School of Mechanical and Electrical Engineering and Automation Shanghai University Shanghai 200444P.R.China Shanghai Drug Rehabilitation Administration Bureau Shanghai 200080 P.R.China Department of Radiology&Functional and Molecular Imaging Key Lab of Shaanxi Province Tangdu Hospital Fourth Military Medical University Xi'anShaanxi 710038P.R.China Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of Education ShanghaiP.R.China Shanghai Intelligent Engineering Technology Research Center for Addiction and Rehabilitation Minhang District 200240 ShanghaiP.R.China

Drug addiction can cause abnormal brain activation changes,which are the root cause of drug craving and brain function *** study enrolled drug abusers to determine the effects of different drugs on brain activation.A functional near-infrared spectroscopy(fNIRS)device was used for the *** study was designed with an experimental paradigm that included the induction of resting and drug addiction *** collected the fNIRS data of 30 drug users,including 10 who used heroin,10 who used Methamphetamine,and 10 who used mixed ***,using Statistical Analysis,the study analyzed the activations of eight functional areas of the left and right hemispheres of the prefrontal cortex of drug addicts who respectively used heroin,Methamphetamine,and mixed drugs,including Left/Right-Dorsolateral prefrontal cortex(L/R-DLPFC),Left/Right-Ventrolateral prefrontal cortex(L/R-VLPFC),Left/Right-Fronto-polar prefrontal cortex(L/R-FPC),and Left/Right Orbitofrontal Cortex(L/R-OFC).Second,referencing the degrees of activation of oxyhaemoglobin concentration(HbO2),the study made an analysis and got the specific activation patterns of each group of the ***,after taking out data which are related to the addicts who recorded high degrees of activation among the three groups of addicts,and which had the same channel numbers,the paper classified the different drug abusers using the data as the input data for Convolutional Neural Networks(CNNs).The average three-class accuracy is 67.13%.It is of great significance for the analysis of brain function errors and personalized rehabilitation.

关键词： Drug addiction fNIRS machine-learning di®erent drug users brain regions activation

Oxygen metabolism-balanced engineered hydrogel microspheres promote the regeneration of the nucleus pulposus by inhibiting acid-sensitive complexes

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Bioactive Materials 2023年第6期24卷 346-360页

作者： Ziang Li feng Cai Jincheng Tang Yichang xu Kaijin guo Zonghan xu Yu feng Kun Xi Yong gu Liang Chen Department of Orthopedics the First Affiliated Hospital of Soochow UniversityOrthopedic InstituteSoochow University188 Shizi RoadSuzhouJiangsu215006PR China Department of Orthopedics the Affiliated Hospital of Xuzhou Medical University99 Huaihai West RoadXuzhouJiangsu221000PR China

Intervertebral disc degeneration(IVDD)is commonly caused by imbalanced oxygen metabolism-triggered *** the shortcomings of antioxidants in IVDD treatment,including instability and the lack of targeting,remains *** and surface modification technologies were combined to graft chitosan nanoparticles encapsulated with strong reductive black phosphorus quantum dots(BPQDs)onto GelMA microspheres via amide bonds to construct oxygen metabolism-balanced engineered hydrogel microspheres(GM@CS-BP),which attenuate extracellular acidosis in nucleus pulposus(NP),block the inflammatory cascade,reduce matrix metalloproteinase expression(MMP),and remodel the extracellular matrix(ECM)in intervertebral discs(IVDs).The GM@CS-BP microspheres reduce H_(2)O_(2) intensity by 229%.Chemical grafting and electrostatic attraction increase the encapsulation rate of BPQDs by 167%and maintain stable release for 21 days,demonstrating the antioxidant properties and sustained modulation of the *** the GM@CS-BP treatment,western blotting revealed decreased acid-sensitive ion channel-3 and inflammatory *** staining in an 8-week IVDD model confirmed the regeneration of ***@CS-BP microspheres therefore maintain a balance between ECM synthesis and degradation by regulating the positive feedback between imbalanced oxygen metabolism in IVDs and *** study provides an in-depth interpretation of the mechanisms underlying the antioxidation of BPQDs and a new approach for IVDD treatment.

关键词： Antioxidant stress Microsphere BPQDs IVDD Reductive agent

Significant impact of deprotonated status on the photoisomerization dynamics of bacteriophytochrome chromophore

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Chinese Chemical Letters 2023年第7期34卷 428-433页

作者： Haiyi Huang Chao xu Kunni Lin Jiawei Peng feng Long gu Zhenggang Lan School of Chemistry South China Normal UniversityGuangzhou 510006China MOE Key Laboratory of Environmental Theoretical Chemistry South China Normal UniversityGuangzhou 510006China SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental SafetySchool of EnvironmentSouthChinaNormal UniversityGuangzhou510006China

We report that the photoinduced dynamics of the phytochrome chromophore is strongly dependent on the protonation/deprotonation states of the pyrrole ring. The on-the-fly surface hopping dynamics simulations were performed to study the photoisomerization of different protonation/deprotonation phytochrome chromophore models. The simulation results indicate that the deprotonations at the pyrrole rings significantly modify the photoinduced nonadiabatic dynamics, leading to distinctive population decay dynamics and different reaction channels. Such feature can be well explained by the formation of the different hydrogen bond network patterns. Therefore, the proper understanding of the photoisomerization mechanism of phytochrome chromophore must take the hydrogen bond network into account. This work provides the new insights into the photobiological functions of phytochrome chromophore and suggests the possible ideas to control of its photoconversion processes for further rational engineering in optical applications.

关键词： Photochemistry Photoreceptors Excited states Non-adiabatic dynamics Conical intersection

Bulk viscosity of interacting magnetized strange quark matter

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Nuclear Science and Techniques 2021年第10期32卷 101-109页

作者： Jian-feng xu School of Physics and Electrical Engineering AnYang Normal UniversityAnyang 455000China

The bulk viscosity of interacting strange quark matter in a strong external magnetic field B m with a real equation of state is *** is found that interquark interactions can significantly increase the bulk viscosity,and the magnetic field B_(m) can cause irregular oscillations in both components of the bulk viscosity,ξ||(parallel to B_(m))and ξ⊥(perpendicular to B_(m)).A comparison with non-interacting strange quark matter reveals that when B_(m) is sufficiently large,ξ⊥is more affected by interactions than ξ||.Additionally,the quasi-oscillation of the bulk viscosity with changes in density may facilitate the for-mation of magnetic ***,the resulting r-mode instability windows are in good agreement with observational data for compact stars in low-mass X-ray ***,the r-mode instability window for interacting strange quark matter in high magnetic fields has a minimum rotation frequency exceeding 1050 Hz,which may explain the observed very high spin frequency of a pulsar with V=1122 Hz.

关键词： Strange quark matter Bulk viscosity Strong magnetic field Strange star R-mode instability window

Experimental demonstration of D-band signals wireless transmission over 30 km

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Science China Technological Sciences 2025年

作者： Yi WEI Xiongwei YANG Jianjun YU Xianming ZHAO Mingxu WANG Jingwen TAN Weiping LI feng ZHAO Chengzhen BIAN Hansong MA Qinyi ZHANG Qiutong ZHANG Bing ZHANG Wen ZHOU Kaihui WANG Sicong xu Jianguo YU State Key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves (MoE)and School of Information Science and Technology Fudan University Harbin Institute of Technology School of Automation Xi'an University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

Due to the rise of innovative technologies like artificial intelligence(AI),the Internet of Things(IoT), and telemedicine, the demand for internet traffic is rapidly increasing. In order to achieve ultra-high-speed wireless communication, many researchers are directing their efforts towards the Dband. The D-band, spanning the frequency band 110–170 GHz, has abundant spectrum resources and license-free characteristics [1,2].

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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He Zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming