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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

Microscopic study on the key process and influence of efficient synthesis of natural gas hydrate by in situ Raman analysis of water microstructure in different systems with temperature drop

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Journal of Energy Chemistry 2023年第7期82卷 317-333,I0008页

作者： Wei Zhang chun-Gang xu Xiao-Sen Li Zhuo-yi Huang Zhao-Yang Chen School of Engineering Science University of Science and Technology of ChinaHefei 230023AnhuiChina Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640GuangdongChina CAS Key Laboratory of Gas Hydrate Guangzhou 510640GuangdongChina Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640GuangdongChina School of Energy Science and Engineering University of Science and Technology of ChinaHefei 230023AnhuiChina

Gas hydrate technology has considerable potential in many ***,due to the lack of understanding of the micro mechanism of hydrate formation,it has not been commercially applied so *** hydrate formation is essentially a gas-liquid-solid phase transition of water and gas molecules at a certain temperature and *** key to the hydrate formation is the transformation of water molecule from disordered arrangement to ordered *** this process,weakly hydrogen bonded water will be correspondingly converted to strongly hydrogen bonded *** in situ Raman analysis and experiments,the position change of the corresponding peaks of the strongly hydrogen bonded water and the weakly hydrogen bonded water was compared in this work,and the key microscopic process and influence of gas hydrate formation in different systems were comprehensively studied and *** is found that,with the decrease of temperature,the OAH of the weakly hydrogen bonded water remains unchanged when the temperature drops to a certain value,which is the key to the transformation of water into cage hydrate rather than *** conversion from the weakly hydrogen bonded water to the strongly hydrogen bonded water is closely related to the gas-liquid interface force,the hydrophilicity/hydrophobicity of the promoter,the ionization degree of liquid,and the electrostatic field of the *** the four most common promoters,tetrahydrofuran(THF)has the highest efficiency in promoting methane(CH4)hydrate ***,this study provides a scientific direction and basis for the development of high efficient hydrate formation promoters,which can effectively weaken the hydrogen bond of weakly hydrogen bonded water and promote the conversion of weakly hydrogen bonded water to strongly hydrogen bonded water.

关键词： Hydrate Conversion Hydrogen bonded water Promoter Micro mechanism

Advances in the Development of Gradient Scaffolds Made of Nano‑Micromaterials for Musculoskeletal Tissue Regeneration

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Nano-Micro Letters 2025年第3期17卷 455-500页

作者： Lei Fang Xiaoqi Lin Ruian xu Lu Liu Yu Zhang Feng Tian Jiao Jiao Li Jiajia xue Beijing Laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China School of Biomedical Engineering Faculty of Engineering and ITUniversity of Technology SydneySydneyNSW 2007Australia

The intricate hierarchical structure of musculoskeletal tissues,including bone and interface tissues,necessitates the use of complex scaffold designs and material structures to serve as tissue-engineered *** has led to growing interest in the development of gradient bone scaffolds with hierarchical structures mimicking the extracellular matrix of native tissues to achieve improved therapeutic *** on the anatomical characteristics of bone and interfacial tissues,this review provides a summary of current strategies used to design and fabricate biomimetic gradient scaffolds for repairing musculoskeletal tissues,specifically focusing on methods used to construct compositional and structural gradients within the *** latest applications of gradient scaffolds for the regeneration of bone,osteochondral,and tendon-to-bone interfaces are ***,the current progress of testing gradient scaffolds in physiologically relevant animal models of skeletal repair is discussed,as well as the challenges and prospects of moving these scaffolds into clinical application for treating musculoskeletal injuries.

关键词： Gradient scaffolds Musculoskeletal tissues Advanced manufacturing Biomaterials Tissue regeneration

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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变电站二次仿真回路虚拟测量系统的实现

自动化技术与应用 2017年第9期36卷 100-104页

作者：吴义纯徐正清王国平黄洁高峰国网安徽省电力公司培训中心安徽合肥230022 北京科东电力控制系统有限责任公司北京100192

变电站二次回路仿真系统通过逼真的虚拟现实实训环境,能有效提高变电运行检修技能培训效果,在实训过程中必须用到虚拟测量工具,因此,研究变电站二次仿真回路虚拟测量系统的结构与技术实现非常必要。以虚拟数字式万用表为例建模,模型中... 详细信息

变电站二次回路仿真系统通过逼真的虚拟现实实训环境,能有效提高变电运行检修技能培训效果,在实训过程中必须用到虚拟测量工具,因此,研究变电站二次仿真回路虚拟测量系统的结构与技术实现非常必要。以虚拟数字式万用表为例建模,模型中增加了仪表使用错误时智能告警功能,可指出实训人员错误,又不损坏仪表,节省实训成本;同时,提出基于通讯中间件的虚拟测量与变电站二次回路仿真系统的交互模型,能满足多台虚拟仪表同时在培训场景中使用,从而完成对二次回路的状态测量、故障消缺等。在实际二次回路检修技能实操培训中应用时,逼真的虚拟仪表仿真环境沉浸感强,在实操训练中体现了优势,取得了良好的培训效果。

关键词：虚拟测量通讯中间件二次回路仿真系统智能告警

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

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei Li Xiaoxiao xu xuan Wu Jiarui Li Shiling Chen Danyang Chen Gaigai Li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong Zheng Jialin Chen Jinghong xu Bin Jiang Lei Li Yawei Li Yuliang Dai Bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

Determination of optimum nitrogen application rates in Zhejiang Province, China, based on rice yields and ecological security

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Journal of Integrative Agriculture 2015年第12期14卷 2426-2433页

作者： LI Yan CHEN yi WU chun-yan TANG xu JI Xiao-jiang Institute of Environment Resource and Soil Fertilizer Zhejiang Academy of Agricultural Sciences

Excessive nitrogen（N） fertilization in intensive agricultural areas such as the plain region of South China has resulted in low nitrogen use efficiency and serious environmental problems. To determine the optimum N application rate, grain yield, apparent nitrogen recovery efficiency（ANRE）, apparent N loss, and ammonium（NH_3） volatilization under different N application rates in the three years from 2012 to 2014 were studied. The results showed that the relationship between grain yields and N application rate in the three years were well fitted by quadratic equations. When N application rate reached 197 kg ha^（–1） in 2012, 199 kg ha^（–1） in 2013 and 196 kg ha^（–1） in 2014, the plateau of the grain yields appeared. With the increase of N application rate, the ANRE for rice decreased which could be expressed with sigmoidal equation; when N application rate was 305 kg ha^（–1） in 2012, 275 kg ha^（–1） in 2013 and 312 kg ha^（–1） in 2014, the curves of ANRE appeared turing points. Besides, the relationship between soil Nresidual and N application rate was fitted by the quadratic equation and the maximums of soil Nresidual were reached in the three years with the N application rate of 206, 244 and 170 kg ha^（–1）, respectively. Statistical analysis indicated that NH3 volatilization and apparent N loss in three years all increased with the increasing N application rate. When the amount of NH3 volatilization increased to 11.6 kg N ha^（–1） in 2012, 40.5 kg N ha^（–1） in 2013 and 57.0 kg N ha^（–1）in 2014, the apparent N loss in the three years had obvious increase. To determine the optimum N application rate, the average N application on the plateau of the grain yield was considered as the lower limit while the average N application rate at the turning points of ANRE, the residual N in soil and apparent N loss was taken as the upper limit. According to the results in three years, the optimum N application rate for rice in Zhejiang was 197–255 kg ha^（–1）.

关键词： optimum nitrogen application rate Zhejiang rice yields ecological security