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Experimental research and analysis of three-finger micro-tweezers

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光学精密工程 2005年第5期13卷 570-574页

作者： HUANG wen-hao xing Hao Department of Precision Machinery and Precision Instrument University of Science and Technology of China HeFei 230027 China

A new type of three-finger micro-tweezer driven by electro-static force was developed for stable manipulation and assembly of micro devices. The whole system consists of micro-tweezers and a specially designed high frequency AC power supply. The free end of the fingers closes and opens with the increase and decrease of the voltage. The tweezers can grasp and manipulate micro objects at size from 30～100 μm. A quantitative simulation method based on boundarx element method(BEM) and equation of energy conservation is introduced to analyze the non-linear behaviors of the tweezer closure. The simulation results agree well with the experimental data.

关键词：镊子 MEMS 微电子机械系统数值模拟

A wide-field and high-resolution lensless compound eye microsystem for real-time target motion perception

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Microsystems & Nanoengineering 2022年第4期8卷 199-207页

作者： Li zhang Haiyang zhan Xinyuan Liu Fei xing Zheng You Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instrument Tsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Integrated Circuits Beijing 100084China

Optical measurement systems suffer from a fundamental tradeoff between the field of view(FOV),the resolution and the update rate.A compound eye has the advantages of a wide FOV,high update rate and high sensitivity to motion,providing inspiration for breaking through the constraint and realizing high-performance optical ***,most existing studies on artificial compound eyes are limited by complex structure and low resolution,and they focus on imaging instead of precise ***,a high-performance lensless compound eye microsystem is developed to realize target motion perception through precise and fast orientation *** microsystem splices multiple sub-FOVs formed by long-focal subeyes,images targets distributed in a panoramic range into a single multiplexing image sensor,and codes the subeye aperture array for distinguishing the targets from different sub-FOVs.A wide-field and high resolution are simultaneously realized in a simple and easy-to-manufacture microelectromechanical system(MEMS)aperture ***,based on the electronic rolling shutter technique of the image sensor,a hyperframe update rate is achieved by the precise measurement of multiple time-shifted spots of one *** microsystem achieves an orientation measurement accuracy of 0.0023°(3σ)in the x direction and 0.0028°(3σ)in the y direction in a cone FOV of 120°with an update rate~20 times higher than the frame *** study provides a promising approach for achieving optical measurements with comprehensive high performance and may have great significance in various applications,such as vision-controlled directional navigation and high-dynamic target tracking,formation and obstacle avoidance of unmanned aerial vehicles.

关键词： precise resolution compound

Resting-state brain network remodeling after different nerve reconstruction surgeries:a functional magnetic resonance imaging study in brachial plexus injury rats

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Neural Regeneration Research 2025年第5期20卷 1495-1504页

作者： Yunting Xiang Xiangxin xing Xuyun Hua Yuwen zhang Xin Xue Jiajia Wu Mouxiong Zheng He Wang Jianguang Xu School of Rehabilitation Science Shanghai University of Traditional Chinese MedicineShanghaiChina Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina Department of Rehabilitation Medicine Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Department of Traumatology and Orthopedics Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan University) Ministry of EducationShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected ***,differences among reconstruction strategies at the brain network level have not been *** study aimed to explore intranetwork changes related to altered peripheral neural pathways after different nerve reconstruction surgeries,including nerve repair,endto-end nerve transfer,and end-to-side nerve ***–Dawley rats underwent complete left brachial plexus transection and were divided into four equal groups of eight:no nerve repair,grafted nerve repair,phrenic nerve end-to-end transfer,and end-to-side transfer with a graft sutured to the anterior upper ***-state brain functional magnetic resonance imaging was obtained 7 months after *** independent component analysis algorithm was utilized to identify group-level network components of interest and extract resting-state functional connectivity values of each voxel within the *** in intra-network resting-state functional connectivity were compared among the *** muscle reinnervation was assessed by behavioral observation(elbow flexion)and *** results showed that alterations in the sensorimotor and interoception networks were mostly related to changes in the peripheral neural *** repair was related to enhanced connectivity within the sensorimotor network,while end-to-side nerve transfer might be more beneficial for restoring control over the affected limb by the original motor *** thalamic-cortical pathway was enhanced within the interoception network after nerve repair and end-to-end nerve *** areas related to cognition and emotion were enhanced after end-to-side nerve *** study revealed important brain networks related to different nerve *** networks may be potential targets for enhancing motor recovery.

关键词： brain functional networks end-to-end nerve transfer end-to-side nerve transfer independent component analysis nerve repair peripheral plexus injury resting-state functional connectivity

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min xing Hai-Dong Qian Qiao Gao Sheng-Lan Xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le Wang wenwu zhang Gang Li xing Cheng Peiqiang Su Yong Wan Xiang Li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury

Numerical Simulation of a Three-Dimensional Fish-like Body Swimming with Finlets

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Communications in Computational Physics 2012年第4期11卷 1323-1333页

作者： Shizhao Wang xing zhan Guowei He LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190P.R.China

The swimming of a 3Dfish-like bodywith finlets is numerically investigated at Re=1000(the Reynolds number is based on the uniform upstream flow and the length of the fish-like body).The finlets are simply modeled as thin rigid rectangular plates that undulate with the *** wake structures and the flow around the caudal peduncle are *** finlets redirect the local flow across the caudal peduncle but the vortical structures in the wake are almost not affected by the *** of hydrodynamic performance has not been found in the simulation based on this simple *** present numerical result is in agreement with that of the work of Nauen and Lauder[***.,204(2001),pp.2251-2263]and partially supports the hypothesis ofWebb[***.,190(1975),pp.1-159].

关键词： Finlets fish swimming Immersed Boundary method wake structure

TAR~*:an improved process similarity measure based on unfolding of Petri nets

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计算机集成制造系统 2012年第8期18卷 1774-1784页

作者： WANG wen-xing WANG Jian-min School of Software Tsinghua University Beijing 100084 China Ministry of Education Key Laboratory for Information System Security Tsinghua UniversityBeijing 100084 China Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Determining the similarity degree between process models was very important for their management,reuse,and *** approaches either focused on process model's structural aspect,or had inefficiency or imprecision in behavioral *** at these problems,a novel similarity measure which extended an existing method named Transition Adjacent Relation(TAR) with improved precision and efficiency named TAR * was *** ability of measuring similarity was extended by eliminating the duplicate tasks without impacting the *** precision,TARs was classified into repeatable and unrepeatable ones to identify whether a TAR was involved in a *** new kinds of TARs were added,one related to the invisible tasks after the source place and before sink place,and the other representing implicit *** efficiency,all TARs based on unfolding instead of its reach ability graph of a labeled Petri net were calculated to avoid state space *** on artificial and real-world process models showed the effectiveness and efficiency of the proposed method.

关键词： transition adjacent relation unfolding Petri nets behavioral similarity

Comparison between UV and VUV photolysis for the pre- and post-treatment of coking wastewater

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Journal of Environmental Sciences 2015年第3期27卷 45-50页

作者： Rui xing Zhongyuan Zheng Donghui wen College of Environmental Sciences and Engineering Key Laboratory of Water and Sediment Sciences (Ministry of Education) Peking University CECEP Liuhe and Talroad Environmental Technology Co. Ltd

In this study, ultraviolet （UV） and vacuum ultraviolet （VUV） photolysis were investigated for the pre-treatment and post-treatment of coking wastewater. First, B-fold diluted raw coking wastewater was irradiated by UV and VUV. It was found that 15.9%-35.4% total organic carbon （TOC） was removed after 24 hr irradiation. The irradiated effluent could be degraded by the acclimated activated sludge. Even though the VUV photolysis removed more chemical oxygen demand （COD） than UV, the UV-irradiated effluent demonstrated better biodegradability. After 4 hr UV irradiation, the biological oxygen demand BODs/COD ratio of irradiated coking wastewater increased from 0.163 to 0.224, and its toxicity decreased to the greatest extent. Second, the biologically treated coking wastewater was irradiated by UV and VUV. Both of them were able to remove 37%-47% TOC within 8 hr irradiation. Compared to UV, VUV photolysis could significantly improve the transparency of the bio-treated effluent. VUV also reduced 7% more ammonia nitrogen （NH4^＋-N）, 17% more nitrite nitrogen （NO2^--N）, and 18% more total nitrogen （TN） than UV, producing 35% less nitrite nitrogen （NO3^--N） as a result. In conclusion, UV irradiation was better in improving the biodegradability of coking wastewater, while VUV was more effective at photolyzing the residual organic compounds and inorganic N-species in the bio-treated effluent.

关键词： Coking wastevcaterpPre-treatment post-treatment UV VUV

Molecular Structure Tailoring of Organic Spacers for High‑Performance Ruddlesden–Popper Perovskite Solar Cells

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Nano-Micro Letters 2025年第2期17卷 314-357页

作者： Pengyun Liu Xuejin Li Tonghui Cai Wei xing Naitao Yang Hamidreza Arandiyan Zongping Shao Shaobin Wang Shaomin Liu School of Materials Science and Engineering State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(East China)Qingdao 266580People’s Republic of China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049People’s Republic of China Centre for Applied Materials and Industrial Chemistry(CAMIC) School of ScienceRMIT UniversityMelbourneVic 3000Australia WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia School of Chemical Engineering The University of AdelaideAdelaideSA 5005Australia School of Engineering Great Bay UniversityDongguan 523000People’s Republic of China

Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)***,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic ***,these issues can be readily resolved by rationally designing spacer cations of *** review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic *** firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of *** we brought three aspects to attention for designing organic ***,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP *** proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications.

关键词： Ruddlesden-Popper perovskites Low-dimensional perovskite solar cells Organic spacers Molecular structure Design strategies