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Detachment Behavior of Gecko Toe in Functional Strategies for Bionic Toe

Journal of Bionic Engineering 2024年第2期21卷 707-717页

作者： Qingfei Han Wei Wang huan shen Xincheng Feng Haoran Zhang Qian Li Yi Sun Huapeng Wu Aihong Ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China Laboratory of Intelligent Machines School of Energy SystemsLappeenranta-Lahti University of Technology53850LappeenrantaFinland State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

Geckos can efficiently navigate complex terrains due to their multi-level adhesive system that is present on their toes.The setae are responsible for the gecko’s extraordinary adhesion and have garnered wide attention from the scientific community.The majority of the reported works in the literature that have dealt with the peeling models mainly focus on the gecko hierarchical adhesive system,with limited attention given to investigating the influence of gecko toe structure on the detachment.Along these lines,to gain a deeper understanding of the rapid and effortless detachment abilities of gecko toes,the peeling behavior of gecko toes on vertical surfaces was primarily investigated in this work.More specifically,the detachment time of a single toe on a smooth acrylic plate was measured to be 0.41±0.21 s.Moreover,it was observed that the toe assumed a"U"-shaped structure upon complete detachment.Additionally,Finite Element Analysis(FEA)models for three different types of gecko toes were developed to simulate both the displacement-peel and the moment-peel modes.Increasing the segmentation of the adhesive layer led to a gradual decrease in the resultant force,as well as the normal and tangential components.Lastly,a gecko-inspired toe model was constructed and powered by Shape Memory Alloy(SMA).A systematic comparison between the vertical drag separation and the outward flip separation was also conducted.From our analysis,it was clearly demonstrated that outward peel separation significantly necessitated the reduction of the peeling force,thus confirming the advantageous nature of the outward motion in gecko toe detachment.Our data not only contribute to a deeper understanding of the gecko detachment behavior but also offer valuable insights for the advancement of the wall-climbing robot feet.

关键词： Gecko toes Detachment behavior Finite element analysis Gecko-inspired toe

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An Aerial–Wall Robotic Insect That Can Land, Climb, and Take Off from Vertical Surfaces

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Research 2024年第1期2023卷 149-163页

作者： Qian Li Haoze Li huan shen Yangguang Yu Haoran He Xincheng Feng Yi Sun Zhiyuan Mao Guangming Chen Zongjun Tian Lida shen Xiangming Zheng Aihong Ji College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjingChina

Insects that can perform flapping-wing flight,climb on a wall,and switch smoothly between the 2 locomotion regimes provide us with excellent biomimetic models.However,very few biomimetic robots can perform complex locomotion tasks that combine the 2 abilities of climbing and flying.Here,we describe an aerial–wall amphibious robot that is self-contained for flying and climbing,and that can seamlessly move between the air and wall.It adopts a flapping/rotor hybrid power layout,which realizes not only efficient and controllable flight in the air but also attachment to,and climbing on,the vertical wall through a synergistic combination of the aerodynamic negative pressure adsorption of the rotor power and a climbing mechanism with bionic adhesion performance.On the basis of the attachment mechanism of insect foot pads,the prepared biomimetic adhesive materials of the robot can be applied to various types of wall surfaces to achieve stable climbing.The longitudinal axis layout design of the rotor dynamics and control strategy realize a unique cross-domain movement during the flying–climbing transition,which has important implications in understanding the takeoff and landing of insects.Moreover,it enables the robot to cross the air–wall boundary in 0.4 s(landing),and cross the wall–air boundary in 0.7 s(taking off).The aerial–wall amphibious robot expands the working space of traditional flying and climbing robots,which can pave the way for future robots that can perform autonomous visual monitoring,human search and rescue,and tracking tasks in complex air–wall environments.

关键词： robot smoothly Vertical

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Development of Wheel-Legged Biped Robots:A Review

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Journal of Bionic Engineering 2024年第2期21卷 607-634页

作者： Xuefei Liu Yi Sun Shikun Wen Kai Cao Qian Qi Xiaoshu Zhang huan shen Guangming Chen Jiajun Xu Aihong Ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

The wheel-legged biped robot is a typical ground-based mobile robot that can combine the high velocity and high efficiency pertaining to wheeled motion and the strong,obstacle-crossing performance associated with legged motion.These robots have gradually exhibited satisfactory application potential in various harsh scenarios such as rubble rescue,military operations,and wilderness exploration.Wheel-legged biped robots are divided into four categories according to the open–close chain structure forms and operation task modes,and the latest technology research status is summarized in this paper.The hardware control system,control method,and application are analyzed,and the dynamic balance control for the two-wheel,biomimetic jumping control for the legs and whole-body control for integrating the wheels and legs are analyzed.In summary,it is observed that the current research exhibits problems,such as the insufficient application of novel materials and a rigid–flexible coupling design;the limited application of the advanced,intelligent control methods;the inadequate understanding of the bionic jumping mechanisms in robot legs;and the insufficient coordination ability of the multi-modal motion,which do not exhibit practical application for the wheel-legged biped robots.Finally,this study discusses the key research directions and development trends for the wheel-legged biped robots.

关键词： Wheel-legged biped robot Wheeled motion Legged motion Control strategy

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Derivatives of Intersection Local Time for Two Independent Symmetricα-stable Processes

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1273-1292页

作者： huan ZHOU Guang Jun shen Qian YU Department of Mathematics Anhui Normal UniversityWuhu 241002P.R.China Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106P.R.China

In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and H?lder continuity.Then we show that this condition is also necessary for the existence of derivatives of intersection local time at the origin.Moreover,we also study the power variation of the derivatives.

关键词： Symmetric stable processes intersection local time exponential integrability power variation

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Analysis of metabolic characteristics of metabolic syndrome in elderly patients with gastric cancer by non-targeted metabolomics

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2419-2428页

作者： huan Zhang Wen-Bing shen Lin Chen Medical School of Chinese PLA Chinese PLA General HospitalBeijing 100853China Department of Gastrointestinal Surgery Shanghai Sixth People’s HospitalShanghai 250063China Department of General Surgery The First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly patients with GC remain unclear.AIM To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics techniques.METHODS In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail group.Sixty-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS group.Nontargeted metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass spectrometry.Multivariate statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway annotation.RESULTS A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics techniques.Compared with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,respectively.Lipid metabolites were significantly increased in the MetS group.In the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased significantly.The combined group was characterized by significantly increased levels of nucleotide metabolites and acidic compounds.The alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obviously enriched in the combined group.CONCLUSION

关键词： Nervous breakdown Metabolic syndrome Elderly individuals Gastric cancer Nontargeted metabolomics

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Acupuncture and moxibustion for irritable bowel syndrome:An umbrella systematic review

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Journal of Integrative Medicine 2024年第1期22卷 22-31页

作者： Yue-ying Ma Zhou Hao Zi-yi Chen Yan-xi shen Hui-rong Liu huan-gan Wu Chun-hui Bao Shanghai Clinical Research Centre for Acupuncture and Moxibustion Yueyang Hospital of Integrated Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Key Laboratory of Acupuncture and Immunological Effects Shanghai University of Traditional Chinese MedicineShanghai 200030China

BackgroundIrritable bowel syndrome(IBS)is a functional bowel disease characterized by abdominal pain or discomfort associated with altered bowel habits.Several clinical studies have demonstrated the effectiveness of acupuncture and moxibustion for IBS.Many systematic reviews of acupuncture and moxibustion for IBS have been published in recent years,but their results are not entirely consistent.ObjectiveTo evaluate the methodological,reporting,and evidence quality of systematic reviews of acupuncture and moxibustion for IBS.Search strategySystematic reviews of acupuncture and moxibustion for IBS published before February 20,2023 were searched in eight databases:PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Infrastructure,Wanfang Data,VIP Database for Chinese Technical Periodicals,and China Biology Medicine.The keywords used for literature search were acupuncture,moxibustion,systematic review,meta-analysis,and irritable bowel syndrome.Inclusion criteriaSystematic reviews and meta-analyses of randomized controlled trials of acupuncture and moxibustion for IBS were included.Data extraction and analysisRelevant information was independently extracted by two investigators.The A MeaSurement Tool to Assess systematic Reviews 2(AMSTAR 2),Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA 2020),and Grading of Recommendations Assessment,Development and Evaluation(GRADE)were used to evaluate the methodological quality,reporting quality and evidence quality,respectively.ResultsA total of 342 studies were retrieved and 15 systematic reviews were included.The results of AMSTAR 2 showed low methodological quality in 2 studies and very low methodological quality in the remaining 13 studies,with main issues being failure to register a protocol,incomplete search strategy,not providing a list of excluded studies,incomplete consideration of the risk of bias in the included studies,and a failure to assess the publication bias.The results of PRISMA 2020 showed seriously deficient reportin

关键词： Irritable bowel syndrome Acupuncture Moxibustion Umbrella systematic review Systematic review

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Studying the variable energy band structure for energy storage materials in charge/discharge process

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Chinese Chemical Letters 2024年第2期35卷 584-589页

作者： Xuancheng Chen Yu huan Ningqiang Sun Yuanhui Su Xuesong shen Guoqing Li Jiaqi Zhang Tao Wei University of Jinan Ji'nan 250022China Weichai Power Co. Ltd.Weifang 261061China

So far,a clear understanding about the relationship of variable energy band structure with the corresponding charge-discharge process of energy storage materials is still lacking.Here,using optical spectroscopy(red-green-blue(RGB)value,reflectivity,transmittance,UV-vis,XPS,UPS)to studyα-Co(OH)_(2) electrode working in KOH electrolyte as the research object,we provide direct experimental evidence that:(1)The intercalation of OH-ions will reduce the valence/conduction band(VB and CB)and band gap energy(Eg)values;(2)The deintercalation of OH-ions corresponds with the reversion of VB,CB and E_(g) to the initial values;(3)The color of Co(OH)_(2) electrode also exhibit regular variations in RGB value during the charge-discharge process.

关键词： Variable energy band structure Energy storage materials Charge-discharge process Optical spectroscopy Supercapacitors

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Application of multidisciplinary in situ simulation training in the treatment of acute ischemic stroke: a quality improvement project

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World Journal of Emergency Medicine 2024年第1期15卷 41-46页

作者： Ganying huang Huijie Yang huan Yao Xinxin Fan Wenqin Xia Yuansheng Xu Xiaoling shen Xue Zhao Fourth School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053China Emergency Medicine Departent Hangzhou First People's HospitalHangzhou 310006China

BACKGROUND:Ischemic stroke refers to a disorder in the blood supply to a local area of brain tissue for various reasons and is characterized by high morbidity,mortality,and disability.Early reperfusion of brain tissue at risk of injury is crucial for the treatment of acute ischemic stroke.The purpose of this study was to evaluate comfort levels in managing acute stroke patients with hypoxemia who required endotracheal intubation after multidisciplinary in situ simulation training and to shorten the door-to-image time.METHODS:This quality improvement project utilized a comprehensive multidisciplinary in situ simulation exercise.A total of 53 participants completed the two-day in situ simulation training.The main outcome was the self-reported comfort levels of participants in managing acute stroke patients with hypoxemia requiring endotracheal intubation before and after simulation training.A 5-point Likert scale was used to measure participant comfort.A paired-sample t-test was used to compare the mean self-reported comfort scores of participants,as well as the endotracheal intubation time and door-to-image time on the fi rst and second days of in situ simulation training.The door-to-image time before and after the training was also recorded.RESULTS:The findings indicated that in situ simulation training could enhance participant comfort when managing acute stroke patients with hypoxemia who required endotracheal intubation and shorten door-to-image time.For the emergency management of hypoxemia or tracheal intubation,the mean post-training self-reported comfort score was signifi cantly higher than the mean pre-training comfort score(hypoxemia:4.53±0.64 vs.3.62±0.69,t=-11.046,P<0.001;tracheal intubation:3.98±0.72 vs.3.43±0.72,t=-6.940,P<0.001).We also observed a decrease in the tracheal intubation and door-to-image time and a decreasing trend in the door-to-image time,which continued after the training.CONCLUSION:Our study demonstrates that the implementation of in situ simulation training in a clinical environmen

关键词： Ischemic stroke Endotracheal intubation Door-to-image time In situ simulation Multidisciplinary approach

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Ex vivo liver resection and auto-transplantation as an alternative for the treatment of liver malignancies: Progress and challenges

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 117-122页

作者： Xin Yang Lu Lu Wen-Wei Zhu Yi-Feng Tao Cong-huan shen Jin-Hong Chen Zheng-Xin Wang Lun-Xiu Qin Hepatobiliary Surgery and Liver Transplantation Centers Department of General SurgeryHuashan Hospital&Cancer Metastasis InstituteFudan UniversityShanghai 200040China

Hepatectomy is still the major curative treatment for patients with liver malignancies.However,it is still a big challenge to remove the tumors in the central posterior area,especially if their location involves the retrohepatic inferior vena cava and hepatic veins.Ex vivo liver resection and auto-transplantation(ELRA),a hybrid technique of the traditional liver resection and transplantation,has brought new hope to these patients and therefore becomes a valid alternative to liver transplantation.Due to its technical difficulty,ELRA is still concentrated in a few hepatobiliary centers that have experienced surgeons in both liver resection and liver transplantation.The efficacy and safety of this technique has already been demonstrated in the treatment of benign liver diseases,especially in the advanced alveolar echinococcosis.Recently,the application of ELRA for liver malignances has gained more attention.However,standardization of clinical practice norms and international consensus are still lacking.The prognostic impact in these oncologic patients also needs further evaluation.In this review,we summarized the principles and recent progresses on ELRA.

关键词： Ex vivo liver resection Liver auto-transplantation Oncology Liver malignancies

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Sulfur doped iron-nitrogen-hard carbon nanosheets as efficient and robust noble metal-free catalysts for oxygen reduction reaction in PEMFC

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Journal of Energy Chemistry 2024年第2期89卷 422-433,I0010页

作者： Bin Liu Jiawang Li Bowen Yan Qi Wei Xingyu Wen Huarui Xie huan He Pei Kang shen Zhi Qun Tian Collaborative Innovation Center of Sustainable Energy Materials School of Physical Science and TechnologyGuangxi UniversityGuangxi Key Laboratory of Electrochemical Energy MaterialsState Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresNanning 530004GuangxiChina

Transition metal-nitrogen-carbon(M-N-C)as a promising substitute for the conventional noble metalbased catalyst still suffers from low activity and durability for oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).To tackle the issue,herein,a new type of sulfur-doped ironnitrogen-hard carbon(S-Fe-N-HC)nanosheets with high activity and durability in acid media were developed by using a newly synthesized precursor of amide-based polymer with Fe ions based on copolymerizing two monomers of 2,5-thiophene dicarboxylic acid(TDA)as S source and 1,8-diaminonaphthalene(DAN)as N source via an amination reaction.The as-synthesized S-Fe-N-HC features highly dispersed atomic Fe Nxmoieties embedded into rich thiophene-S doped hard carbon nanosheets filled with highly twisted graphite-like microcrystals,which is distinguished from the majority of M-N-C with soft or graphitic carbon structures.These unique characteristics endow S-Fe-N-HC with high ORR activity and outstanding durability in 0.5 M H_(2)SO_(4).Its initial half-wave potential is 0.80 V and the corresponding loss is only 21 m V after 30,000 cycles.Meanwhile,its practical PEMFC performance is a maximum power output of 628.0 mW cm^(-2)and a slight power density loss is 83.0 m W cm^(-2)after 200-cycle practical operation.Additionally,theoretical calculation shows that the activity of Fe Nxmoieties on ORR can be further enhanced by sulfur doping at meta-site near FeN_(4)C.These results evidently demonstrate that the dual effect of hard carbon substrate and S doping derived from the precursor platform of amid-polymers can effectively enhance the activity and durability of Fe-N-C catalysts,providing a new guidance for developing advanced M-N-C catalysts for ORR.

关键词： Transition metal-nitrogen-carbon Oxygen reduction reaction Hard carbon Amide based polymer reaction Proton exchange membrane cells

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