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Journal of Bionic Engineering 2024年第1期21卷 192-208页

作者： ang Chen Bifeng Song ZhiheWang kang Liu Dong Xue Xiaojun Yang School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China harbin Institute of Technology Shenzhen 518055China

This paper is based on a previously developed bio-inspired Flapping Wing Aerial Vehicle(FWAV),RoboFalcon,which can fly with a morphing-coupled flapping *** this paper,a simple flapping stroke control system based on hall effect sensors is designed and applied,which is capable of assigning different up-and down-stroke speeds for the RoboFalcon platform to achieve an adjustable downstroke *** aerodynamic and power characteristics of the morphing-coupled flapping pattern and the conventional flapping pattern with varying downstroke ratios are measured through a wind tunnel experiment,and the corresponding aerodynamic models are developed and analyzed by the nonlinear least squares *** relatively low power consumption of the slow-downstroke mode of this vehicle is verified through outdoor flight *** results of wind tunnel experiments and flight tests indicate that increased downstroke duration can improve aerodynamic and power performance for the RoboFalcon platform.

关键词： Flapping wing aerial vehicle(FWAV) Downstroke ratio Bio-inspired design Morphing-coupled flapping

Effects of dynamical spanwise retraction and stretch on flapping-wing forward flights

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Chinese Journal of Aeronautics 2024年第4期37卷 181-202页

作者： kang LIU Bifeng SONG ang ChEN Zhihe Wang Dong XUE Wenqing Yang School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Intelligent Aircraft Research Center Chengdu Technological UniversityChengdu 610031China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China harbin Institute of Technology Shenzhen 518055China

Birds and bats retract and stretch their wings dynamically during each flap in level flights, implying intriguing mechanisms for the aerodynamic performance improvement of flapping wings. A numerical investigation into the aerodynamic effects of such bio-inspired concept in forward flights has been performed based on a three-dimensional wing in plunging motion and a twosection wing in flapping motion. The currently considered Reynolds number and Strouhal number are Re=1.5×10^(5) and St=0.3, respectively. During the research, the mean angle of attack is varied in relatively wide ranges to achieve lift-thrust interconversion for the wings. The conclusive results show that dynamical spanwise retraction and stretch has induced three absolutely desirable scenarios for the oscillating wings in forward flights, namely producing more lift and consuming less power for a given thrust generation, producing more thrust and consuming less power for a given lift generation, and producing more lift and more thrust while consuming less power. Furthermore,the morphing wings have alleviated periodical aerodynamic load fluctuations compared with the non-morphing baseline. The mechanism of the aerodynamic effects of the bionic morphing mode is analyzed with the aid of field visualization. The current article is the first to reveal the absolute advantages of the bionic spanwise morphing. hopefully, it may help comprehend the behaviors of natural fliers and provide inspirations for performance enhancement of micro artificial flappingwing vehicles.

关键词： Flapping wing Morphing wing Bionic Aerodynamics Vortex Flight

NiS ultrafine nanorod with translational and rotational symmetry

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National Science Review 2024年第7期11卷 218-225页

作者： Jianxin kang Qi hu Ruixuan Zhang ang Gao Zhongning h.ang Ziming Su Ke Pei Qinghua Zhang Li-Min Liu Renchao Che Lin Gu Er-Jia Guo Lin Guo School of Chemistry Beihang University Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative Materials Academy for Engineering&Technology Fudan University Zhejiang Laboratory Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials School of Materials Science and Engineering Tsinghua University Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physics Beihang University

Anisotropy is a significant and prevalent characteristic of materials, conferring orientation-dependent properties, meaning that the creation of original symmetry enables key functionality that is not found in nature. Even with the advancements in atomic machining, synthesis of separated symmetry in different directions within a single structure remains an extraordinary challenge. here, we successfully fabricate NiS ultrafine nanorods with separated symmetry along two directions. The atomic structure of the nanorod exhibits rotational symmetry in the radial direction, while its axial direction is characterized by divergent translational symmetry, surpassing the conventional crystalline structures known to date. It does not fit the traditional description of the space group and the point group in three dimensions, so we define it as a new structure in which translational symmetry and rotational symmetry are separated. Further corroborating the atomic symmetric separation in the electronic structure, we observed the combination of stripe and vortex magnetic domains in a single nanorod with different directions, in accordance with the atomic *** manipulation of nanostructure at the atomic level introduces a novel approach to regulate new properties finely, leading to the proposal of new nanotechnology mechanisms.

关键词： separated symmetry NiS anisotropy structure atomic machining magnetic domain

A neural m^(6)A pathway regulates behavioral aggregation in migratory locusts

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Science China(Life Sciences) 2024年第6期67卷 1242-1254页

作者： Xianliang h.ang Qing Li Yanan Xu ang Li Shanzheng Wang Yusheng Chen Chunrui Zhang Xia Zhang hailin Wang Cong Lv Baofa Sun Shaoqin Li Le kang Bing Chen School of Life Science Institutes of Life Science and Green DevelopmentHebei UniversityBaoding 071002China College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute of health Sciences Anhui UniversityHefei 230601China Beijing Institute of Genomics Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100101China

RNA N6-methyladenosine(m^(6)A),as the most abundant modification of messenger RNA,can modulate insect behaviors,but its specific roles in aggregation behaviors remain ***,we conducted a comprehensive molecular and physiological characterization of the individual components of the methyltransferase and demethylase in the migratory locust Locusta *** results demonstrated that METTL3,METTL14 and ALKBh5 were dominantly expressed in the brain and exhibited remarkable responses to crowding or *** individual knockdown of methyltransferases(i.e.,METTL3 and METTL14)promoted locust movement and conspecific attraction,whereas ALKBh5 knockdown induced a behavioral shift toward the solitary ***,global transcriptome profiles revealed that m^(6)A modification could regulate the orchestration of gene expression to fine tune the behavioral aggregation of *** summary,our in vivo characterization of the m^(6)A functions in migratory locusts clearly demonstrated the crucial roles of the m^(6)A pathway in effectively modulating aggregation behaviors.

关键词： RNA methylation N^(6)-methyladenosine transcriptional orchestration aggregation behavior Locusta migratoria

high-density lipoprotein regulates angiogenesis by affecting autophagy via miRNA-181a-5p

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Science China(Life Sciences) 2024年第2期67卷 286-300页

作者： Bi-ang kang hua-Ming Li Ya-Ting Chen Meng-Jie Deng Yan Li Yue-Ming Peng Jian-Jun Gao Zhi-Wei Mo Jia-Guo Zhou Zhi-Jun Ou Jing-Song Ou Division of Cardiac Surgery Cardiovascular Diseases InstituteThe First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China National-Guangdong Joint Engineering Laboratory for Diagnosis and Treatment of Vascular Diseases Guangzhou 510080China NhC key Laboratory of Assisted Circulation(Sun Yat-sen University) Guangzhou 510080China Guangdong Provincial Engineering and Technology Center for Diagnosis and Treatment of Vascular Diseases Guangzhou 510080China Division of Vascular Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Department of Pharmacology Cardiac and Cerebral Vascular Research CenterZhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510080China Division of hypertension and Vascular Diseases Department of CardiologyCardiovascular Diseases InstituteThe First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Guangdong Provincial Key Laboratory of Brain Function and Disease Zhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510080China

We previously demonstrated that normal high-density lipoprotein(nhDL)can promote angiogenesis,whereas hDL from patients with coronary artery disease(d hDL)is dysfunctional and impairs *** plays a critical role in angiogenesis,and hDL regulates ***,it is unclear whether n hDL and d hDL regulate angiogenesis by affecting *** cells(ECs)were treated with n hDL and d hDL with or without an autophagy ***,endothelial nitric oxide synthase(e NOS)expression,miRNA expression,nitric oxide(NO)production,superoxide anion(O2^(·-))generation,EC migration,and tube formation were evaluated.n hDL suppressed the expression of miR-181a-5p,which promotes autophagy and the expression of e NOS,resulting in NO production and the inhibition of O2^(·-)generation,and ultimately increasing in EC migration and tube formation.d hDL showed opposite effects compared to n hDL and ultimately inhibited EC migration and tube *** found that autophagy-related protein 5(ATG5)was a direct target of ***5 silencing or miR-181a-5p mimic inhibited n hDL-induced autophagy,e NOS expression,NO production,EC migration,tube formation,and enhanced O2^(·-)generation,whereas overexpression of ATG5 or miR-181a-5p inhibitor reversed the above effects of d ***5 expression and angiogenesis were decreased in the ischemic lower limbs of hypercholesterolemic low-density lipoprotein receptor null(LDLr^(-/-))mice when compared to C57BL/6 ***5 overexpression improved angiogenesis in ischemic hypercholesterolemic LDLr^(-/-)*** together,nhDL was able to stimulate autophagy by suppressing miR-181a-5p,subsequently increasing e NOS expression,which generated NO and promoted *** contrast,d hDL inhibited angiogenesis,at least partially,by increasing miR-181a-5p expression,which decreased autophagy and e NOS expression,resulting in a decrease in NO production and an increase in O2^(·-)*** findings reveal a nov

关键词： high-density lipoprotein angiogenesis autophagy ATG5 miRNA endothelial nitric oxide synthase

An Experimental Study on Response and Control of a Flapping-Wing Aerial Robot Under Wind Gusts

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Journal of Bionic Engineering 2024年第1期21卷 209-223页

作者： Kazuki Shimura hikaru Aono Chang-kwon kang Graduate School of Science and Technology Shinshu University3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical Engineering and Robotics 3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical and Aerospace Engineering University of Alabama in HuntsvilleTechnology Hall N266HuntsvilleAL35899USA

Bioinspired flapping-wing micro-air-vehicles(FWMAVs)have the potential to be useful aerial tools for gathering information in various *** recent advancements in manufacturing technologies and better understanding of aerodynamic mechanisms behind of the flapping flight,outdoor flights have become a ***,to fully realize the potential of FWMAVs,further improvements are necessary,particularly in terms of stability and robustness under gusty *** this study,the response and control of a tailless two-winged FWMAV under the wind gusts are *** experiments are conducted with a one-degree-of-freedom gimbal to focus on effects of wind gusts on the rotational motion of the ***-derivative and sliding-mode controls are adopted for the attitude *** present that the body angles changed in time and reached approximately 50°at the maximum due to the wing *** sliding-mode controller can more effectively control the rotational angle in the presence of disturbances and both the wing speed and changes in wind speed have an impact on the effectiveness of attitude *** results contribute to the development of of tailless two-winged,single-motor driven FWMAVs in terms of the design of attitude controller and testing apparatus.

关键词： Flapping-wing micro-air vehicles Sliding-mode control Pitch and roll angle-Wind gus

Tailored heterostructured Ni_(3)N-NiO nano-frameworks for boosting electrocatalytic oxygen evolution via surface-modulated plasma strategy

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Nano Research 2024年第9期17卷 7909-7917页

作者： Bo Ouyang haonan Qin Chao Sun Yilin Deng ang Li Jipeng Zhu Erjun Kan Rajdeep Singh Rawat MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing School of ScienceNanjing University of Science&TechnologyNanjing 210094China The Laboratory of Road and Bridge Civil EngineeringSchool of ScienceNanjing University of Science&TechnologyNanjing 210094China Institute for Energy Research Jiangsu UniversityZhenjiang 212013China Natural Sciences and Science Education National Institute of EducationNanyang Technological University637616Singapore

The facile reconfiguration of phases plays a pivotal role in enhancing the electrocatalytic production of h2 through heterostructure *** chemical methods have been explored extensively for this purpose,plasma-based techniques offer a promising avenue for achieving heterostructured ***,the conventional plasma approach introduces complexities,leading to a multi-step fabrication process and challenges in precisely controlling partial surface structure modulation due to the intricate interaction *** our pursuit of heterostructures with optimized oxygen evolution reaction(OER)behavior,we have designed a facile auxiliary insulator-confined plasma system to directly attain a Ni_(3)N-NiO heterostructure(hNiNO).By meticulously controlling the surface heating process during plasma processing,such approach allows for the streamlined fabrication of hNiNO *** resulting nano-framework exhibits outstanding catalytic performance,as evidenced by its overpotential of 320 mV at a current density of 10 mA·cm^(-2),in an alkaline *** stands in stark contrast to the performance of NiO-covered Ni_(3)N fabricated using the conventional plasma method(sNiNO).Operando plasma diagnostics,coupled with numerical simulations,further substantiates the influence of surface heating due to auxiliary insulator confinement of the substrate on typical plasma parameters and the formation of the Ni_(3)N-NiO nanostructure,highlighting the pivotal role of controlled surface temperature in creating a high-performance heterostructured electrocatalyst.

关键词： structural modulation auxiliary insulator-confined plasma surface heating control heterostructure electrocatalytic O_(2) evolution

Novel Perovskite Oxide hybrid Nanofibers Embedded with Nanocatalysts for highly Efficient and Durable Electrodes in Direct CO_(2) Electrolysis

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Nano-Micro Letters 2024年第5期16卷 214-230页

作者： Akromjon Akhmadjonov Kyung Taek Bae kang Taek Lee Department of Mechanical Engineering KAISTDaejeon 34141Republic of Korea KAIST Graduate School of Green Growth and Sustainability Daejeon 34141Republic of Korea

The unique characteristics of nanofibers in rational electrode design enable effec-tive utilization and maximizing material properties for achieving highly efficient and sustainable CO_(2) reduction reactions( CO_(2)RRs)in solid oxide elec-trolysis cells(SOECs).however,practical appli-cation of nanofiber-based electrodes faces chal-lenges in establishing sufficient interfacial contact and adhesion with the dense *** tackle this challenge,a novel hybrid nanofiber electrode,La_(0.6)Sr_(0.4)Co_(0.15)Fe_(0.8)Pd_(0.05)O_(3-δ)(h-LSCFP),is developed by strategically incorporating low aspect ratio crushed LSCFP nanofibers into the excess porous interspace of a high aspect ratio LSCFP nanofiber framework synthesized via electrospinning *** consecutive treatment in 100% h_(2) and CO_(2) at 700°C,LSCFP nanofibers form a perovskite phase with in situ exsolved Co metal nanocatalysts and a high concentration of oxygen species on the surface,enhancing CO_(2) *** SOEC with the h-LSCFP electrode yielded an outstanding current density of 2.2 A cm^(-2) in CO_(2) at 800°C and 1.5 V,setting a new benchmark among reported nanofiber-based *** twinning of the h-LSCFP reveals improved contact adhesion and increased reaction sites for CO_(2)*** present work demonstrates a highly catalytically active and robust nanofiber-based fuel electrode with a hybrid structure,paving the way for further advancements and nanofiber applications in CO_(2)-SOECs.

关键词： Nanofibers Fuel electrodes Digital twinning CO_(2)reduction reaction Solid oxide electrolysis cells

Origin of water in the Moon

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National Science Review 2024年第6期11卷 10-12页

作者： hejiu hui Ziyan han kang Shuai State Key Laboratory of Mineral Deposits Research & Lunar and Planetary Science Institute School of Earth Sciences and Engineering Nanjing University CAS Center for Excellence in Comparative Planetology CAS Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics

It has been well known since the Apollo era that the Moon is relatively depleted in volatiles as a result of the Moonformation impact and the subsequent planetary differentiation. The lunar interior was believed to have been extremely dry [1]. The discovery of indigenous water (a collective term for h-bearing species Oh, h2O, etc.) in various lunar materials [2–5] has driven a paradigm shift in our knowledge of water in the Moon, from a dry to a wet Moon.

关键词： LUNAR hYDROGEN TERRESTRIAL INTERIOR

microRNA-2184 orchestrates Mauthner-cell axon regeneration in zebrafish via syt3 modulation

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Journal of Genetics and Genomics 2024年第9期51卷 911-921页

作者： Xinghan Chen Yueru Shen Zheng Song Xinliang Wang huaitong Yao Yuan Cai Zi-ang Zhao Bing hu hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefeiAnhui 230026China The First Affiliated hospital of USTC Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China Center for Advanced Interdisciplinary Science and Biomedicine of IhM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China

MicroRNAs(miRNAs)play a significant role in axon regeneration following spinal cord ***,the functions of numerous miRNAs in axon regeneration within the central nervous system(CNS)remain largely ***,we elucidate the positive role of microRNA-2184(miR-2184)in axon regeneration within zebrafish Mauthner cells(M-cells).The upregulation of miR-2184 in a single M-cell can facilitate axon regeneration,while the specific sponge-induced silencing of miR-2184 leads to impeded *** show that syt3,a downstream target of miR-2184,negatively regulates axon regeneration,and the regeneration suppression modulated by syt3 depends on its binding to Ca2+.Furthermore,pharmacological stimulation of the cAMP/PKA pathway suggests that changes in the readily releasable pool may affect axon *** data indicate that miR-2184 promotes axon regeneration of M-cells within the CNS by modulating the downstream target syt3,providing valuable insights into potential therapeutic strategies.

关键词： Axon regeneration Axon ablation miR-2184 syt3 Readily releasable pool