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Journal of Bionic Engineering 2024年第1期21卷 112-125页

作者： Chuanku Yi Xuechao Chen yu Zhang Zhangguo yu Haoxiang qi Yaliang Liu qiang Huang School of Mechatronical Engineering Beijing Institute of TechnologyZizhuyaunHaidianBeijing 100081China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Tec

There are many theories and tools for human or robot motion simulation,but most of them require complex *** LNZN model(a simplified model named by the proposers)simplifies the human model and facilitates simulation of the Ground Reaction Force(GRF)of body landing by spring damping model and ignoring joint rotation movements,which can reduce the amount of computation *** this paper,the LNZN model of human running is selected as the basis and is modified to obtain the LNZN model of a robot,which expands the application of the LNZN *** to the structure of the human foot,a foot structure is then added to the simplified model to reduce the *** also applied driving forces to the new model to simulate the whole high jump motion of the robot to expand the functions of the LNZN *** obtained GRF data were anastomotic to the actual experimental *** addition,the effects of variables,such as the mass,hardness,and damping,of the foot on the GRF at the moment of landing were also ***,based on the guidelines obtained for the design of the robot’s foot structure,we fabricated new robot’s feet and installed them on the actual robot and achieved a better cushioning effect than the original foot in experiments.

关键词： LNZN model-GRF simulation Humanoid foot structure Foot parameters

Transient stimulated Raman scattering spectroscopy and imaging

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Light(Science & Applications) 2024年第4期13卷 654-663页

作者： qiaozhi yu Zhengjian Yao Jiaqi Zhou Wenhao yu Chenjie Zhuang Yafeng qi Hanqing Xiong National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing 100871China Biomedical Engineering Department College of Future TechnologyPeking UniversityBeijing 100871China

Stimulated Raman scattering(SRS)has been developed as an essential quantitative contrast for chemical imaging in recent ***,while spectral lines near the natural linewidth limit can be routinely achieved by state-of-the-art spontaneous Raman microscopes,spectral broadening is inevitable for current mainstream SRS imaging *** is because those SRS signals are all measured in the frequency *** is a compromise between sensitivity and spectral resolution:as the nonlinear process benefits from pulsed excitations,the fundamental time-energy uncertainty limits the spectral ***,the spectral range and acquisition speed are mutually *** we report transient stimulated Raman scattering(T-SRS),an alternative time-domain strategy that bypasses all these fundamental conjugations.T-SRS is achieved by quantum coherence manipulation:we encode the vibrational oscillations in the stimulated Raman loss(SRL)signal by femtosecond pulse-pair sequence excited vibrational wave packet *** Raman spectrum was then achieved by Fourier transform of the time-domain SRL *** all Raman modes are impulsively and simultaneously excited,T-SRS features the natural-linewidth-limit spectral line shapes,laser-bandwidth-determined spectral range,and improved ***~150-fs laser pulses,we boost the sensitivity of typical Raman modes to the sub-mM *** all-plane-mirror high-speed time-delay scanning,we further demonstrated hyperspectral SRS imaging of live-cell metabolism and high-density multiplexed imaging with the natural-linewidth-limit spectral resolution.T-SRS shall find valuable applications for advanced Raman imaging.

关键词： scattering excited mutually

Controlled flight of a self-powered micro blimp driven by insect-sized flapping-wing thrusters

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Chinese Journal of Aeronautics 2024年第6期37卷 127-136页

作者： Xian yu Zhiwei LIU Jiaming LENG Mingjing qi Xiaojun YAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijng 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beihang UniversityBeijing 100191China

Micro aerial platforms face significant challenges in achieving long controlled endurance as most of the energy is consumed to overcome the weight of the *** this study,we present a controllable micro blimp that addresses this issue through the use of a helium-filled *** micro blimp has a long axis of 23 cm and is propelled by four insect-sized flapping-wing thrusters,each weighing 80 mg and with a wingspan of 3.5 *** distributed thrusters enable controlled motions and provide the micro blimp with an advantage in flight endurance compared to multirotors or flapping-wing micro aerial vehicles at the same size *** enhance the performance of the controlled flight,we propose a wireless control module that enables manipulation from a distance of up to 100 ***,a smartphone application is developed to send instructions to the circuit board,allowing the blimp to turn left and right,ascend and descend,and achieve a combination of these movements *** findings demonstrate that this micro blimp is one of the smallest controlled self-powered micro blimps to date.

关键词： Microairvehicle Aircraft control Self-powered micro blimp Flapping-wing thruster Wireless flight

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Advancement in porphyrin/phthalocyanine compounds-based perovskite solar cells

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Changes of growth-climate relationships of Smith fir forests along an altitudinal gradient

结构化学 2024年第3期43卷 55-66页

作者： Chen Lu Zefeng yu jing Cao State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000PR China

Porphyrin and phthalocyanine compounds belong to a class of large and aromatic macrocyclic *** to their unique structures and electronic properties,they have found widespread applications in optoelectronic *** recent years,the doping of porphyrins and phthalocyanines into perovskite solar cells(PSCs)has emerged as an effective strategy to enhance device performance and *** doping strategy enables the modulation of perovskite film crystallization and surface defects,thereby improving charge transfer and enhancing the photo-conversion *** sensitizers,porphyrins and phthalocyanines absorb light in the visible and near-infrared spectral ranges,providing an advantage to the light absorption characteristics of ***,their roles in interface modification and defect repair contribute to the long-term stability of the *** central metal of porphyrin can also adsorb ions and prevent the migration of harmful *** review summarizes the recent progress in the research on porphyrin and phthalocyanine-doped PSCs,empha-sizing their potential value in enhancing optoelectronic performance,increasing stability and expanding the application scope of these devices.

关键词： Porphyrin Phthalocyanine Charge transport Interfacial chemistry Perovskite solar cells

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Journal of Forestry Research 2024年第5期35卷 37-46页

作者： Jiacheng Zheng jing Yang Hengfeng Jia Lixin Lyu Jiayang Langzhen qi-Bin Zhang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Linzhou Bureau of Meteorology LinzhouLhasa 851611TibetPeople’s Republic of China Institute of Plateau Ecology Tibet Agricultural and Animal Husbandry UniversityLinzhi 860000TibetPeople’s Republic of China

Temporal changes in the relationship between tree growth and climate have been observed in numerous forests across the *** patterns and the possible regu-lators(e.g.,forest community structure)of such changes are,however,not well understood.A vegetation survey and analyses of growth-climate relationships for Abies georgei ***(Smith fir)forests were carried along an altitudi-nal gradient from 3600 to 4200 m on Meili Snow Mountain,southeastern Tibetan *** results showed that the associations between growth and temperature have declined since the 1970s over the whole transect,while response to standardized precipitation-evapotranspiration indices(SPEI)strengthened in the mid-and *** between growth and vegetation data showed that tree growth was more sensitive to drought in stands with higher species richness and greater shrub *** stress on growth may be increased by heavy competition from shrub and herb *** results show the non-stationary nature of tree growth-climate associations and the linkage to for-est community *** components should be considered in future modeling and forecasting of forest dynamics in relation to climate changes.

关键词： Climate change Tree rings Altitudinal gradient Community structure Plant diversity

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Examination of wnt signaling mediated melanin transport and shell color formation in Pacific oyster(Crassostrea gigas)

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Marine Life Science & Technology 2024年第3期6卷 488-501页

作者： yue Min qi Li Hong yu Shaojun Du Key Laboratory of Mariculture Ministry of Educationand College of FisheriesOcean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Institute of Marine and Environmental Technology Department of Biochemistry and Molecular BiologyUniversity of Maryland School of MedicineBaltimore 21240USA

Mollusca exhibit remarkable diversity in shell coloration,attributed to the presence of melanin,a widely distributed pigment with various essential roles,such as mechanical strengthening,antioxidation and ***,the regulatory network governing melanogenesis and melanin transport in molluscs remains poorly *** this study,we conducted a systematic analysis of melanin distribution and transport in the Pacific oyster,utilizing light microscopy and high-resolution transmission electron *** addition,we characterized CgWnt1 and CgWnt2b-a in Crassostrea gigas,and analyzed Wnt signaling in melanocyte *** analysis revealed that these genes were predominantly expressed in the mantle of black-shelled individuals,particularly in the outer fold of the ***,we employed RNA interference and inhibitors to specifically inhibit Wnt signaling in both in vivo and in *** results revealed impaired melanogenesis and diminished tyrosinase activity upon Wnt signaling *** findings suggest the crucial role of Wnt ligands and downstream factors in *** summary,our study provides valuable insights into the regulatory mechanism of shell pigmentation in *** demonstrating the promotion of melanogenesis through Wnt signaling modulation,we contribute to a better understanding of the complex processes underlying molluscan melanin production and shell coloration.

关键词： Melanogenesis Melanosome trafficking WIF-1

Recent advances in phenazine-linked porous catalysts toward photo/electrocatalytic applications and mechanism

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Green Energy & Environment 2024年第10期9卷 1518-1549页

作者： Yang Liu yu Zhang Zhao-Di Yang Liqiang jing Heilongjiang Provincial Key Laboratory of CO2 Resource Utilization and Energy Catalytic Materials School of Material Science and Chemical EngineeringHarbin University of Science and Technology Institute of Process Engineering Chinese Academy of Sciences Key Laboratory of Functional Inorganic Materials Chemistry(Ministry of Education) School of Chemistry and Materials Science International Joint Research Center for Catalytic Technology Heilongjiang University

In recent years, porous organic catalysts have been developed and become research hotspots in photo/electrocatalysis due to their inherent pores, high specific surface area, chemical and thermal stability, and diverse functional building blocks. Phenazine-linked organic catalysts,exhibited excellent conjugation, electrical conductivity, chemical, and thermal stability, could bring in N atoms with specific numbers and positions to regulate electron levels, anchor metals, and absorb near-infrared light, which expands solar energy utilization. These advantages of the phenazine-linked catalysts attracted our group and numerous researchers to conduct experimental and computational work on photo/electrocatalytic applications and mechanisms. This review summarizes the recent significant research progress, synthesis methods, photo/electrocatalytic performance, and applications of relative phenazine-linked catalysts. Furthermore, the photo/electrocatalytic mechanism was systematized and summarized by combining experiments and density functional theory calculations simultaneously.

关键词： Phenazine-linked porous catalysts Photo/electrocatalytic applications Catalytic mechanism

The role of exosomes in adult neurogenesis:implications for neurodegenerative diseases

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Neural Regeneration Research 2024年第2期19卷 282-288页

作者： Zhuoyang yu Yan Teng jing Yang Lu Yang Institute of Neurology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Laboratory of Aging Research School of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina

Exosomes are cup-shaped extracellular vesicles with a lipid bilayer that is approximately 30 to 200 nm in *** are widely distributed in a range of body fluids,including urine,blood,milk,and *** exert biological function by transporting factors between different cells and by regulating biological pathways in recipient *** an important form of intercellular communication,exosomes are increasingly being investigated due to their ability to transfer bioactive molecules such as lipids,proteins,mRNAs,and microRNAs between cells,and because they can regulate physiological and pathological processes in the central nervous *** neurogenesis is a multistage process by which new neurons are generated and migrate to be integrated into existing neuronal *** the adult brain,neurogenesis is mainly localized in two specialized niches:the subventricular zone adjacent to the lateral ventricles and the subgranular zone of the dentate *** increasing body of evidence indicates that adult neurogenesis is tightly controlled by environmental conditions with the *** recent studies,exosomes released from different sources of cells were shown to play an active role in regulating neurogenesis both in vitro and in vivo,thereby participating in the progression of neurodegenerative disorders in patients and in various disease ***,we provide a state-of-the-art synopsis of existing research that aimed to identify the diverse components of exosome cargoes and elucidate the therapeutic potential of exosomal contents in the regulation of neurogenesis in several neurodegenerative *** emphasize that exosomal cargoes could serve as a potential biomarker to monitor functional neurogenesis in *** addition,exosomes can also be considered as a novel therapeutic approach to treat various neurodegenerative disorders by improving endogenous neurogenesis to mitigate neuronal loss in the central nervous system.

关键词： adult neurogenesis Alzheimer’s disease amyotrophic lateral sclerosis exosome Huntington’s disease neurodegenerative disease neurogenic niches Parkinson’s disease

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Benchmarking visual SLAM methods in mirror environments

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Computational Visual Media 2024年第2期10卷 215-241页

作者： Peter Herbert jing Wu Ze Ji yu-Kun Lai School of Computer Science and Informatics Cardiff UniversityAbacws BuildingSenghennydd RdCardiff CF244AGUK School of Engineering Cardiff UniversityQueen’s BuildingsThe ParadeCardiff CF243AAUK

Visual simultaneous localisation and mapping(vSLAM)finds applications for indoor and outdoor navigation that routinely subjects it to visual complexities,particularly mirror *** effect of mirror presence(time visible and its average size in the frame)was hypothesised to impact localisation and mapping performance,with systems using direct techniques expected to perform ***,a dataset,MirrEnv,of image sequences recorded in mirror environments,was collected,and used to evaluate the performance of existing representative *** ORB-SLAM3 and BundleFusion appear to show moderate degradation of absolute trajectory error with increasing mirror duration,whilst the remaining results did not show significantly degraded localisation *** mesh maps generated proved to be very inaccurate,with real and virtual reflections colliding in the reconstructions.A discussion is given of the likely sources of error and robustness in mirror environments,outlining future directions for validating and improving vSLAM performance in the presence of planar *** MirrEnv dataset is available at https://***/10.17035/d.2023.0292477898.

关键词： visual simultaneous localisation and mapping(vSLAM) mirror localisation mapping reflection datase

Assessing the dynamics of O2 desorption from cobalt phthalocyanine by in situ electrochemical scanning tunneling microscopy

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Journal of Energy Chemistry 2024年第11期98卷 144-148页

作者： yu-qi Wang yue Feng Xiang Wang Dong Wang CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular Sciences Beijing National Laboratory for Molecular Science (BNLMS) Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

We report here the in situ electrochemical scanning tunneling microscopy（ECSTM） study of cobalt phthalocyanine（CoPc）-catalyzed O2evolution reaction（OER） and the dynamics of *** self-assembled CoPc monolayer is fabricated on Au（111） substrate and resolved by ECSTM in 0.1 M KOH *** OH-adsorption on CoPc prior to OER is observed in ECSTM *** OER,the generated O2adsorbed on Co Pc is observed in the CoPc *** step experiment is employed to monitor the desorption of OER-generated O2from CoPc,which results in the decreasing surface coverage of CoPc-O2with *** rate constant of O2desorption is evaluated through data *** insights into the dynamics of Co-O2dissociation at the molecular level via in situ imaging help understand the role of Co-O2in oxygen reduction reaction（ORR） and OER.

关键词： Cobalt phthalocyanine Electrochemical scanning tunneling microscopy Oxygen evolution reaction