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Experimental Study on the Effect of Increased Downstroke Duration for an FWAV with Morphing-coupled Wing Flapping Configuration

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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

Comprehensive DNA barcode reference library and optimization of genetic divergence threshold facilitate the exploration of species diversity of green lacewings (Neuroptera: Chrysopidae)

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Insect Science 2024年第2期31卷 613-632页

作者： yan Lai Kaiyu Li Xingyue liu Deparment of Entomology Cllege of Plant ProtectionChina Agricultural UniversityBejingChina College of Bioogical Sciencs China Agricultural UniversityBeijingChina

Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory ***,the taxonomy of Chrysopidae lacks a comprehensive revision,which impedes the exploration of species diversity as well as the selection and the conservation of green lacewings as biocontrol *** have established a DNA barcode reference library of the Chinese green lacewings based on an approximately complete sampling(95.63%)in 25 of the 34 provincial regions in China,comprising 1119 barcodes of 25 genera and 197 species(representing 85%genera and 43.62%species from China).Combining other 1049 high quality green lacewing DNA barcodes,we first inferred the optimal threshold of interspecific genetic divergence(1.87%)for successful species identification in multiple simulated scenarios based on present *** further inferred the threshold of genetic divergence(7.77%)among genera with biocontrol *** inference and performance of the threshold appears to be mainly associated with the completeness of sampling,the proportion of closely related species,and the analytical *** new combinations,Apertochrysa platypa(yang&yang,1991)***.,Apertochrysa shennongana(yang&Wang,1990)***.,Apertochrysa pictifacialis(yang,1988)***.,Apertochrysa helana(yang,1993)***.,Plesiochrysa rosulata(yang&yang,2002)***.,and Signochrysa hainana(yang&yang,1991),are proposed according to integrative species *** library and optimal threshold will effectively facilitate the exploration of species diversity of green *** study also provides a methodological reference in molecular delimitation of other insects.

关键词： Chrysopidae DNA barcode genetic distance optimal threshold species delimitation

Efficiency-first spraying mission arrangement optimization with multiple UAVs in heterogeneous farmland with varying pesticide requirements

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Information Processing in Agriculture 2024年第2期11卷 237-248页

作者： yang Li yanqiang Wu Xinyu xue xuemei liu yang Xu Xinghua liu Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014PR China College of Mechanical&Electronic Engineering Shandong Agricultural UniversityTai'an 271018PR China Key Laboratory of Modern Agricultural Equipment Ministry of Agriculture and Rural AffairsNanjing 210014PR China Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment Tai’an 271018PR China Shandong Provincial Engineering Laboratory of Agricultural Equipment Intellectualization Tai’an 271018PR China

Combining multiple crop protection Unmanned Aerial Vehicles(UAVs)as a team for a scheduled spraying mission over farmland now is a common way to significantly increase ***,given some issues such as different configurations,irregular borders,and especially varying pesticide requirements,it is more important and more complex than other multi-Agent Systems(MASs)in common *** this work,we focus on the mission arrangement of UAVs,which is the foundation of other high-level cooperations,systematically propose Efficiency-first Spraying Mission Arrangement Problem(ESMAP),and try to construct a united problem framework for the mission arrangement of crop protection ***,to characterise the differences in sub-areas,the varying pesticide requirement per unit is well considered based on Normalized Difference Vegetation Index(NDVI).Firstly,the mathematical model of multiple crop-protection UAVs is established and ESMAP is ***,an acquisition method of a farmland’s NDVI map is proposed,and the calculation method of pesticide volume based on NDVI is ***,an improved Genetic Algorithm(GA)is proposed to solve ESMAP,and a comparable combination algorithm is *** simulations for algorithm analysis are carried out within MATLAB,and it is determined that the proposed GA is more efficient and accurate than the ***,a mission arrangement tested with three UAVs was carried out to validate the effectiveness of the proposed GA in spraying *** results illustrated that it performed well,which took only 90.6%of the operation time taken by the combination algorithm.

关键词： Efficiency-first optimization Mission arrangement Multi-UAVs Heterogeneous farmland

Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin

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Petroleum Science 2024年第1期21卷 87-99页

作者： yan-Nan Du Kong-You Wu Yin liu yan-Ying Li Zi-Cheng Cao You-Wei Cui Jun liu Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina Exploration and Development Research Institute SINOPEC Northwest Oilfield BranchUrumqi 830011XinjiangChina The Fifth Gas Production Plant Changqing OilfieldPetroChinaXi'an 710018ShaanxiChina

With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention *** by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related *** contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon *** this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim ***-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic ***,the stress state of each point of the STGs was calculated using seismic curvature ***,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were *** results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped *** STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both *** shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient *** study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area.

关键词： Tarim Basin Sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control

A new nonfullerene acceptor with an extended π conjugation core enables ternary organic solar cells approaching 19%efficiency

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Nano Research 2024年第5期17卷 4062-4068页

作者： Chunyan liu Nailiang Qiu Zhengjin Li yan Lu School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China School of Chemistry Chemical Engineering and MaterialsJining UniversityQufu 273155China

In organic solar cells(OSCs),it is an effective way to improve the power conversion efficiency(PCE)by adding a guest component with appropriate absorption and energy levels in the host ***,a new nonfullerene acceptor(NFA)named TBF-2Cl was developed by the strategy of expanding theπconjugated core of 2,2’-(((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b’]dithiophene-2,7-diyl)bis(methaneylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IDT-4Cl)with two benzene *** increase of benzene units,TBF-2Cl exhibits higher lowest unoccupied molecular orbital(LUMO)level of-3.75 eV than that of one benzene unit based NFA IDT-4Cl and fluorene core based NFA F-2Cl,which facilitates enhancing the open-circuit voltage(V_(oc))of ternary ***,TBF-2Cl film shows a medium optical bandgap with the absorption range from 500-800 nm,being well complementary with the wide bandgap polymer donor D18 and narrow bandgap NFA ***,a remarkable PCE of 18.92%with a high short-circuit current density(J_(sc))of 27.40 mA·cm^(-2),a fill factor(FF)of 0.749,especially an outstanding V_(oc) of 0.922 V was achieved for the optimal ternary device based on D18:TBF-2Cl:CH-6F,surpassing the binary counterpart(17.08%).The findings provide insight into the development of new guest acceptors for obtaining more efficient OSCs.

关键词： medium optical bandgap high lowest unoccupied molecular orbital(LUMO)level the third component ternary organic solar cell high open-circuit voltage

Atorvastatin, etanercept and the nephrogenic cardiac sympathetic remodeling in chronic renal failure rats

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Journal of Geriatric Cardiology 2024年第4期21卷 443-457页

作者： Jing-Yue XU Zheng-Kai xue Ya-Ru ZHANG Xing liu xue ZHANG Xi yanG Tong liu Kang-Yin CHEN Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of CardiologyTianjin Institute of Cardiologythe Second Hospital of Tianjin Medical UniversityTianjinChina

BACKGROUND Chronic renal failure(CRF) patients are predisposed to arrhythmias, while the detailed mechanisms are unclear. We hypothesized the chronic inflammatory state of CRF patients may lead to cardiac sympathetic remodeling, increasing the incidence of ventricular arrhythmia(VA) and sudden cardiac death. And explored the role of atorvastatin and etanercept in this *** A total of 48 rats were randomly divided into sham operation group(Sham group), CRF group, CRF + atorvastatin group(CRF + statin group), and CRF + etanercept group(CRF + rhTNFR-Fcgroup). Sympathetic nerve remodeling was assessed by immunofluorescence of growth-associated protein 43(GAP-43) and tyrosine hydroxylase positive area fraction. Electrophysiological testing was performed to assess the incidence of VA by assessing the ventricular effective refractory period and ventricular fibrillation threshold. The levels of tumor necrosis factor-alpha(TNF-α) and interleukin-1beta were determined by Western blotting and enzyme-linked immunosorbent *** Echocardiogram showed that compared with the Sham group, left ventricular end-systolic diameter and ventricular weight/body weight ratio were significantly higher in the CRF group. Hematoxylin-eosin and Masson staining indicated that myocardial fibers were broken, disordered, and fibrotic in the CRF group. Western blotting, enzyme-linked immunosorbent assay,immunofluorescence and electrophysiological examination suggested that compared with the Sham group, GAP-43 and TNF-α proteins were significantly upregulated, GAP-43 and tyrosine hydroxylase positive nerve fiber area was increased, and ventricular fibrillation threshold was significantly decreased in the CRF group. The above effects were inhibited in the CRF + statin group and the CRF + *** In CRF rats, TNF-α was upregulated, cardiac sympathetic remodeling was more severe, and the nephrogenic cardiac sympathetic remodeling existed. Atorvastatin and etanercept c

关键词： remodeling cardiac inhibited

Stability of water yield in watersheds

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Science China Earth Sciences 2024年第2期67卷 483-496页

作者： Yu yan Zhiyong liu Xiaohong CHEN Liyan HUANG Center for Water Resources and Environment School of Civil EngineeringSun Yat-Sen UniversityGuangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China

The hydrological system of a watershed is intricately influenced by both underlying characteristics and climate *** the variability in water yield is essential for effective water resources management and water security in the context of changing *** this study,we adopted the Budyko framework and leveraged simulations from the CMIP6 model to investigate the compensation effects of climate and underlying characteristics on watershed water *** on Taylor expansion and Budyko framework,we estimated the sensitivity of watershed water yield to climate and underlying characteristics(the first-and second-order partial derivatives).By combining external watershed characteristics(e.g.,water yield ratios and underlying characteristics)with internal sensitivity coefficients,this study further used vine copula and principal component analysis to quantify the stability of watershed water *** findings show:(1)Water-yield changes related to underlying characteristics could be offset by climate-related water-yield changes across all climate zones,maintaining the water yield ratio steady(i.e.,the compensation effects).(2)However,global watersheds will turn more sensitive to underlying characteristics and less sensitive to climate variation in the *** climate-and underlying-related sensitivities increase in watersheds with arid climates.(3)The stability of watershed water yield will gradually diminish in the *** 1901–1950to 2051–2100,the global stability of 280 watersheds drops from 0.054 to 0.021(i.e.,stability index identified by the joint probability).Particularly,the largest change in stability of water yield reaches-0.347±0.18 in arid *** semi-arid,semihumid,and humid regions,the changes are-0.039±0.010,-0.028±0.005,and-0.005±0.002,*** findings provide a reference for the future sustainable water resources development under climate change,highlighting the vulnerability of the water resources in ari

关键词： Hydrological system stability Compensation effects on water yield Sensitivities Budyko-Fu decomposition framework Global watersheds

NIR-II fluorescence imaging in liver tumor surgery: A narrative review

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 29-44页

作者： Zihao liu Lifeng yan Qingsong Hu Dalong Yin Department of General Surgery Anhui Provincial Hospital Anhui Medical UniversityHefei 230001P.R.China Department of Hepatobiliary Surgery and Centre for Leading Medicine and Advanced Technologies of IHM The First A±liated Hospital of USTC Division of Life Sciences and Medicine University of Science and Technology of China Hefei Anhui 230001P.R.China Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter Chemistry and Department of Chemical Physics University of Science and Technology of China Hefei 230026P.R.China Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery The First Affiliated Hospital of USTC Division of Life Sciences and Medicine University of Science and Technology of ChinaHefei 230001P.R.China

In liver tumor surgery,the recognition of tumor margin and radical resection of microcancer focis have always been the crucial points to reduce postoperative recurrence of ***,naked-eye inspection and palpation have limited effectiveness in identifying tumor boundaries,and traditional imaging techniques cannot consistently locate tumors in real *** an intraoperative real-time navigation imaging method,NIRfluorescence imaging has been extensively studied for its simplicity,reliable safety,and superior sensitivity,and is expected to improve the accuracy of liver tumor *** recent years,the research focus of NIRfluorescence has gradually shifted from the-rst near-infrared window(NIR-I,700–900 nm)to the second near-infrared window(NIR-II,1000–1700 nm).Fluorescence imaging in NIR-II reduces the scattering effect of deep tissue,providing a preferable detection depth and spatial resolution while signi-cantly eliminating liver autofluorescence background to clarify tumor *** combined with tumor antibodies will further improve the precision offluorescence-guided surgical *** the development of a bunch offluorophores with phototherapy ability,NIR-II can integrate tumor detection and treatment to explore a new therapeutic strategy for liver ***,we review the recent progress of NIR-IIfluorescence technology in liver tumor surgery and discuss its challenges and potential development direction.

关键词： Fluorescence guided-surgery liver cancer near infrared-II optical imaging

Performance of composite foundations with different load transfer platforms and substratum stiffness over silty clay

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Journal of Mountain Science 2024年第5期21卷 1761-1774页

作者： ZHANG Shuming liu yan YUAN Shengyang liu Xianfeng JIANG Guanlu liu Junyan School of Civil Engineering and Architecture University of JinanJinan 250022China The Engineering Technology Research Center for Urban Underground Engineering Supporting and Risk Monitoring of Shandong Province Jinan 250022China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-speed Railway Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of *** is crucial to understand the stress distribution across the embankment width and the behaviour of unreinforced ***,five centrifuge tests were conducted to examine the bearing and deformation behaviours of NPRS(Non-Connected Piled Raft Systems)and GRPS(GeosyntheticReinforced Pile-Supported systems)with varying substratum stiffness,then a comparative analysis was conducted on embankment settlement,pressures underneath the embankments,and axial forces along the *** results indicated that greater substratum stiffness correlates with reduced settlement and deformation at various *** occurring 5 meters from the embankment toe includes settlement in NPRS and upward movement in *** potential sliding surface is primarily located within the embankment in NPRS,whereas it may extend through both the embankment and foundation in *** pile-soil stress ratio and efficiency in NPRS are higher than in GRPS across the *** axial force borne by end-bearing piles is significantly greater than that by floating *** the buried depth increases,the axial force in GRPS initially rises then declines,whereas in NPRS,it remains relatively constant within a certain range before *** study aids in assessing the applicability of composite foundations in complex railway environments and provides a reference for procedural measures under similar conditions.

关键词： Centrifuge modelling Composite foundation Failure mode Load transfer platform Substratum Stiffness Silty clay