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Journal of Electronic Science and Technology 2024年第3期22卷 69-79页

作者： Yin Zhang Ding-feng Duan School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu611731China

We estimate tree heights using polarimetric interferometric synthetic aperture rada.(PolInSAR)da.a constructed by the dual-polarization(dual-pol)SAR da.a and random volume over the ground(RVoG)*** the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is *** S_(HH)da.a were constructed using the SVH da.a,and polarimetric SAR(PolSAR)da.a were *** proposed approach was first verified in simulation with satisfactory *** was next applied to construct PolInSAR da.a by a pair of dual-pol Sentinel-1A da.a at Duke Forest,North Carolina,*** to local observations and forest descriptions,the range of estimated tree heights was overall *** the heights with the ICESat-2 tree heights at 23 sampling locations,relative errors of 5 points were within±30%.Errors of 8 points ranged from 30%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is *** instance,the construction of PolSAR da.a should not be limited to using SVH,and a combination of SVH and SVV should be ***,an ensemble of tree heights derived from multiple PolInSAR da.a can be considered since tree heights do not vary much with time frame in months or one season.

关键词： Constructed polarimetric SAR da.a Dual polarization Sentinel-1 SAR da.a Polarimetric interferometric SAR Random volume over the ground model Tree height estimation

Tailoring chaotic motion of microcavity photons in ray and wave dynamics by tuning the curvature of space

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 107-112页

作者： Wei Lin Yechun Ding Yongsheng Wang Peng Li Yanpeng Zhang feng Yun feng Li Key Laboratory for Physical Electronics and Devices of the Ministry of Education Shaanxi Key Lab of Information Photonic TechniqueSchool of Electronic Science and EngineeringFaculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China Department of Electrical and Photonics Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark Center for Regenerative and Reconstructive Medicine Med-X InstituteThe First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China Solid-State Lighting Engineering Research Center Xi’an Jiaotong UniversityXi’an 710049China

Microcavity photon dynamics in curved space is an emerging interesting area at the crossing point of nanophotonics,chaotic science,and non-Euclidean *** report the sharp difference between the regular and chaotic motions of cavity photons subjected to the varying space *** the island modes of regular motion rise in the phase diagram in the curved space,the chaotic modes show special mechanisms to ada.t to the space curvature,including the fast diffusion of ray dynamics,and the localization and hybridization of the Husimi wavepackets among different periodic *** observations are unique effects enabled by the combination of the chaotic trajectory,the wave nature of light,and the non-Euclidean orbital motion,and therefore make the system a versatile optical simulator for chaotic science under quantum mechanics in curved space-time.

关键词： microcavity chaotic motion curved space

Is appendoscope a new option for the treatment of acute appendicitis?

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World Journal of Gastroenterology 2024年第28期30卷 3386-3392页

作者： Shu-Jiong feng Yi-feng Zhou Jian-feng Yang Hong-Zhang Shen Guang-Xing Cui Xiao-feng Zhang Department of Gastroenterology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Key Laboratory of Integrated Traditional Chinese and Western Medicine for Biliary and Pancreatic Diseases of Zhejiang ProvinceHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Hangzhou Institute of Digestive DiseasesHangzhou 310000Zhejiang ProvinceChina

Acute appendicitis is a common surgical *** is commonly caused by obstruction of the appendiceal lumen due to fecaliths,tumors,or lymphoid *** over a century,appendectomy has been the primary treatment for acute *** Groves performed the first open appendectomy in *** 1983,Kurt Semm completed the first laparoscopic appendectomy,heralding a new era in ***,appendectomy is associated with certain complications and a rate of negative *** have suggested controversy over the impact of appendectomy on the development of inflammatory bowel disease and Parkinson’s disease,but an increasing number of studies indicate a possible positive correlation between appendectomy and colorectal cancer,gallstones,and cardiovascular *** the recognition that the appendix is not a vestigial organ and the advancement of endoscopic technology,Liu proposed the endoscopic retrograde appendicitis *** is an effective minimally invasive alternative for treating uncomplicated acute *** team has developed an appendoscope with a disposable digital imaging system operated through the biopsy channel of a colonoscope and successfully applied it in the treatment of *** article provides an overview of the progress in endoscopic treatment for acute appendicitis and offers a new perspective on the future direction of appendiceal disease treatment.

关键词： Acute appendicitis Endoscopic technology Endoscopic retrograde appendicitis therapy Appendoscope Appendiceal disease treatment

Intersection theory rules symbology

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 93-104页

作者： Jiaqi Chen Bo feng Lilin Yang Beijing Computational Science Research Center Beijing 100084China Zhejiang Institute of Modern Physics School of PhysicsZhejiang UniversityHangzhou 310027China Peng Huanwu Center for Funda.ental Theory Hefei 230026China

We propose a novel method to determine the structure of symbols for any family of polylogarithmic Feynman *** the d log-bases and simple formulas for the leading order and next-to-leading contributions to the intersection numbers,we give a streamlined procedure to compute the entries in the coefficient matrices of canonical differential equations,including the symbol letters and the rational *** also provide a selection rule to decide whether a given matrix element must be *** symbol letters are deeply related to the poles of the integrands and also have interesting connections to the geometry of Newton *** method can be applied to many cutting-edge multi-loop *** simplicity of our results also hints at the possible underlying structure in perturbative quantum field theories.

关键词： scattering amplitude Feynman integral symbology

An effective bimetallic oxide catalyst of RuO_(2)-Co_(3)O_(4) for alkaline overall water splitting

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Nano Research 2024年第5期17卷 3785-3793页

作者： Fangfang Ren Jiayu Xu Ligang feng College of Chemical and Environmental Engineering Yancheng Teachers UniversityYancheng 224007China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

The rational design of effective bifunctional electrocatalysts is of paramount importance for overall water-splitting technology in sustainable energy ***,bimetallic oxide catalysts(RuO_(2)-Co_(3)O_(4))derived from Ru combined MOF-derivatives(MOF=metal-organic framework)were demonstrated effective for overall water splitting in an alkaline solution,owing to the combined merits such as the two-dimensional interconnected network structure,the synergetic coupling effects and increased chemical *** as-prepared RuO_(2)-Co_(3)O_(4) only requires an overpotential of 260 mV for oxygen evolution and 75 mV for hydrogen evolution at 10 mA/cm^(2) in 1 M KOH solution;a low cell voltage of 1.54 V was required to reach the kinetic current density of 10 mA/cm^(2) for the water electrolysis when supporting on glass carbon electrode,and very good stability for 40 h was *** and theoretical results demonstrated the electronic structure optimization of bimetallic RuO_(2)-Co_(3)O_(4) compared to the individual metal oxide,which promoted interface charges redistribution and the d-band center downshift,resulting in increased activity and stability for water-splitting *** work provides a feasible approach for developing bimetallic oxides for application in energy-relevant electrocatalysis reactions.

关键词： ruthenium dioxide cobalt oxide metal-organic frameworks heterostructures overall water splitting

Sample Generation for Security Region Bounda.y Identification Based on Topological Features of Historical Operation da.a

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1087-1095页

作者： Xiaokang Wu Wei Xu feng Xue College of Energy and Electrical Engineering Hohai UniversityNanjingChina NARI Group Corporation NanjingChina State Grid Electric Power Research Institute NanjingChina

Since the scale and uncertainty of the power sys-tem have been rapidly increasing,the computation efficiency of constructing the security region bounda.y(SRB)has become a prominent *** on the topological features of histori-cal operation da.a,a sample generation method for SRB identi-fication is proposed to generate evenly distributed samples,which cover dominant security *** bounda.y sample pair(BSP)composed of a secure sample and an unsecure sam-ple is defined to describe the feature of *** resolution,sampling,and span indices are designed to evaluate the cover-age degree of existing BSPs on the SRB and generate samples closer to the *** on the feature of flat distribution of BSPs over the SRB,the principal component analysis(PCA)is adopted to calculate the tangent vectors and normal vectors of ***,the sample distribution can be expanded along the tangent vector and corrected along the normal vector to cover different security ***,a sample set is randomly gen-erated based on the IEEE standa.d example and another new sample set is generated by the proposed *** results in-dicate that the new sample set is closer to the SRB and covers different security modes with a small calculation time cost.

关键词： Clustering analysis principal component analysis(PCA) sample generation security region bounda.y(SRB)

Multiscale observation in wide-spatial rada. surveillance based on coherent Fda.design

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Science China(Information Sciences) 2024年第2期67卷 232-252页

作者： Lei YU feng HE Yi SU College of Electronics Science National University of Defense Technology

Wide-spatial rada. surveillance missions are challenging tasks, requiring an increased power budget and agility in transmission aimed at extracting information from multiple targets in different environments. These requirements necessitate high transmitting degrees of freedom(DOF) to achieve the objective of multiscale observation for specific tasks in specialized regions of interest. Herein, we exploit the multiscale observation ability in wide-spatial rada. surveillance based on frequency diverse array(Fda.rada.. The proposed method facilitates spatial anisotropic control of multiple rada. resources, including the transmitting waveforms, beampattern, and bandwidth. By utilizing a coherent Fda.rada., we offer principles for the selection of baseband waveforms, in addition to the quantitative design of the beampattern gain and optimal bandwidth from the perspective of detection. The feasibility of the proposed method is valida.ed through numerical experiments, thus indicating the potential in wide-spatial rada. surveillance. Moreover,this work can be regarded as a preliminary attempt to gauge the efficacy of the computational array, a novel academic concept.

关键词： multi-scale observation wide-spatial surveillance frequency diverse array (Fda. beampattern synthesis frequency diversity gain computational array

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN Lei HU Rong feng LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Improved observation of colonized roots reveals the regulation of arbuscule development and senescence by drought stress in the arbuscular mycorrhizae of citrus

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Horticultural Plant Journal 2024年第2期10卷 425-436页

作者： Xilong Yin Wei Zhang Zengwei feng Guangda.feng Honghui Zhu Qing Yao College of Horticulture South China Agricultural UniversityKey Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China)Ministry of Agriculture and Rural AffairsGuangdong Province Key Laboratory of Microbial Signals and Disease ControlGuangzhouGuangdong 510642China Key Laboratory of Agricultural Microbiomics and Precision Application Ministry of Agriculture and Rural AffairsGuangdong Provincial Key Laboratory of Microbial Culture Collection and ApplicationKey Laboratory of Agricultural MicrobiomicsState Key Laboratory of Applied Microbiology Southern ChinaGuangdong Microbial Culture Collection Center(GDMCC)Institute of MicrobiologyGuangdong Academy of SciencesGuangzhouGuangdong 510070China

Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to drought stress, remain unclear, which is mainly due to the difficulty in clearing and staining lignified roots with the conventional method. Here, we improved the observation of colonized roots of citrus plants with the sectioning method, which enabled the clear observation of AM fungal structures. Furthermore, we investigated the effects of one week of drought stress on arbuscule development and senescence with the sectioning method. Microscopy observations indicated that drought stress significantly decreased mycorrhizal colonization (F%and M%) although it did not affect plant growth performance. Fluorescence probes (WGA 488 and/or Nile red) revealed that drought stress inhibited arbuscule development by increasing the percentage of arbuscules at the early stage and decreasing the percentages of arbuscules at the midterm and mature stages. Meanwhile, drought stress accelerated arbuscule senescence, which was characterized by the increased accumulation of neutral lipids. Overall, the sectioning method developed in this study enables the in-depth investigation of arbuscule status, and drought stress can inhibit arbuscule development but accelerate arbuscule senescence in the colonized roots of citrus plants. This study paves the way to elaborately dissecting the arbuscule dynamics in the roots of fruit tree species in response to diverse abiotic stresses.

关键词： Arbuscular mycorrhizae Citrus Drought stress Arbuscule development Arbuscule senescence Fruit tree species

From non-carbon host toward carbon-free lithium-sulfur batteries

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Nano Research 2024年第3期17卷 1337-1365页

作者： Yanqi feng Hui Liu Qiongqiong Lu School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW)Dresden e.V. Helmholtzstraβe 2001069 DresdenGermany School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China

Lithium-sulfur(Li-S)batteries with advantages of high energy densities(2600 Wh·kg^(-1)/2800 Wh·L^(-1))and sulfur abunda.ce are regarded as promising candida.es for next-generation high-energy ***,the conventional carbon host used in sulfur cathodes suffers from poor chemical adsorption towards Li-polysulfides(LPS)in liquid electrolyte and sluggish redox kinetics,leading to low capacity and rate ***,carbon host used in Li metal anode with the intrinsic property of poor lithiophilicity and high Li-nucleation barrier gives rise to uncontrollable dendrite growth and further battery ***,non-carbon hosts with chemical adsorption toward LPS and catalytic activity for accelerating LPS redox conversion as well as lithiophilic property for guiding uniform Li deposition are proposed and demonstrated a high efficiency in both sulfur cathodes and Li metal *** this review,the principle and challenges of Li-S batteries are first presented,then recent work using non-carbon hosts in Li-S batteries is summarized comprehensively,and the mechanism of non-carbon host in improving sulfur utilization and stabilizing Li metal anode is discussed in ***,remaining challenges and outlook on the implementation of non-carbon host for practical carbon-free Li-S batteries are also provided.

关键词： sulfur cathode Li metal anode polysulfides adsorption catalytic effect Li dendrite carbon-free lithium-sulfur batteries