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Research in Astronomy and Astrophysics 2023年第10期23卷 184-191页

作者： Xue Chen J.L.Han w.q.su Z.L.Yang D.J.Zhou National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of FAST NAOCChinese Academy of SciencesBeijing 100101China

Radio astronomy observations are frequently impacted by radio frequency interference(RFI).we propose a novel method,named 2σCRF,for cleaning RFI in the folded data of pulsar observations,utilizing a Bayesian-based model called conditional random fields(CRFs).This algorithm minimizes the“energy”of every pixel given an initial *** standard deviations(i.e.,rms values)of the folded pulsar data are utilized as pixels for all subintegrations and ***-RFI data without obvious interference is treated as“background noise,”while RFI-affected data have different classes due to their exceptional rms *** initial labeling can be automated and is adaptive to the actual *** CRF algorithm optimizes the label category for each pixel of the image with the prior initial *** demonstrate the efficacy of the proposed method on pulsar folded data obtained from Five-hundred-meter Aperture Spherical radio Telescope *** can effectively recognize and tag various categories of RFIs,including broadband or narrowband,constant or instantaneous,and even weak RFIs that are unrecognizable in some pixels but picked out based on their *** results are comparable to those obtained via manual labeling but without the need for human intervention,saving time and effort.

关键词： methods:data analysis techniques:image processing (stars:)pulsars:general

FAST Pulsar *** Profiles of 682 Pulsars

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Research in Astronomy and Astrophysics 2023年第10期23卷 71-175页

作者： P.F.wang J.L.Han J.Xu C.wang Y.Yan w.C.Jing w.q.su D.J.Zhou T.wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China

Pulsar polarization profiles form a very basic database for understanding the emission processes in a pulsar *** careful polarization calibration of the 19-beam L-band receiver and verification of beamoffset observation results,we obtain polarization profiles of 682 pulsars from observations by the Five-hundredmeter Aperture Spherical radio Telescope(FAST)duringthe Galactic Plane Pulsar Snapshot survey and other normal FAST *** them,polarization profiles of about 460 pulsars are observed for the first *** profiles exhibit diverse *** pulsars have a polarization position angle curve with a good S-shaped swing,some with orthogonal modes;some have components with highly linearly polarized components or strong circularly polarized components;some have a very wide profile,coming from an aligned rotator,and some have an interpulse from a perpendicular rotator;some wide profiles are caused by interstellar *** derive geometric parameters for 190 pulsars from the S-shaped position angle curves or with orthogonal *** find that the linear and circular polarization or the widths of pulse profiles have various frequency *** with a large fraction of linear polarization are more likely to have a large Edot.

关键词： polarization (stars:)pulsars:general astronomical databases:miscellaneous

Ultra-high-q free-space coupling to microtoroid resonators

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Light(Science & Applications) 2024年第4期13卷 682-695页

作者： Sartanee suebka Euan McLeod Judith su wyant College of Optical Sciences University of ArizonaTucsonAZUSA Department of Biomedical Engineering University of ArizonaTucsonAZUSA

whispering gallery mode(wGM)microtoroid resonators are one of the most sensitive biochemical sensors in existence,capable of detecting single *** main barrier for translating these devices out of the laboratory is that light is evanescently coupled into these devices though a tapered optical *** hinders translation of these devices as the taper is fragile,suffers from mechanical vibration,and requires precise ***,we eliminate the need for an optical fiber by coupling light into and out from a toroid via free-space coupling and monitoring the scattered resonant light.A single long working distance objective lens combined with a digital micromirror device(DMD)was used for light injection,scattered light collection,and *** obtain q-factors as high as 1:6´108 with this *** induced transparency(EIT)-like and Fano resonances were observed in a single cavity due to indirect coupling in free *** enables improved sensing *** large effective coupling area(~10μm in diameter for numerical aperture=0.14)removes the need for precise *** performance was verified by combining the system with the frequency locked whispering evanescent resonator(FLOwER)approach to perform temperature sensing experiments.A thermal nonlinear optical effect was examined by tracking the resonance through FLOwER while adjusting the input *** believe that this work will be a foundation for expanding the implementation of wGM microtoroid resonators to real-world applications.

关键词： coupling scattered precise

An automatic q-factor matching method for eliminating 77%of the ZRO of a MEMS vibratory gyroscope in rate mode

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Microsystems & Nanoengineering 2024年第3期10卷 35-48页

作者： Jingbo Ren Tong Zhou Yi Zhou Yixuan Li Yan su School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210000China

Mismatching quality factors(q-factors)is one of the main factors causing zero-rate output(ZRO)in degenerate(DE)Micro-Electro-Mechanical Systems(MEMS)vibratory *** eliminate the ZRO of the DE MEMS gyroscope,this study introduces a method for real-time identification and automatic matching of q-factors in rate *** leveraging the vibration characteristics of the DE MEMS vibratory gyroscope in rate mode,dedicated online test methods are designed to determine the q-factors for both the drive and sense modes,enabling online identification of the q-factor ***,an automatic q-factor matching system is designed utilizing the mechanical-thermal dissipation mechanism of the resistive *** effectiveness of this proposed method is validated through simulations and experiments conducted on a MEMS disk resonator gyroscope(DRG).The results show a measurement error within 4%for q-factor identification,and automatic q-factor matching effectively reduces the ZRO by 77%.Employing this automatic q-factor matching method successfully reduces the ZRO that is caused by the mismatching of q-factors in the MEMS DRG from 0.11°/s to 0.025°/s and improves the bias instability(BI)from 0.40°/s to 0.19°/s.

关键词： matching mode method

Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 135-145页

作者： su Shuo Long Jun Duan qinghua Zhou Han Zhao Yi SINOPEC Research Institute of Petroleum Processing Co.Ltd. Beijing 100083

To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established *** molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular *** results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen *** on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur *** results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions.

关键词： lubricating oil antioxidant molecular mechanism molecular design antioxidant performance

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang su Ze-Yu Li Li-Le Liu Guo-Xiang Dong Xiao-Bao wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were *** volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov *** in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and *** fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap *** results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing *** on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

Antigen epitopes of animal coronaviruses:a mini-review

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Animal Diseases 2024年第1期4卷 19-26页

作者： Mingjun su Guanghui Zheng Xiangwen Xu Houhui Song Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics&Advanced TechnologyZhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health ManagementChina-Australia Joint Laboratory for Animal Health Big Data AnalyticsCollege of Animal Science and Technology&College of Veterinary Medicine of ZhejiangA&F University666 Wusu StreetLin'an DistrictHangzhou 311300Zhejiang ProvinceChina

Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health ***,prevention and control of emerging and re-emerging animal coronaviruses is a great *** mecha-nisms of virus-mediated immune responses have important implications for research on virus prevention and *** antigenic epitope is a chemical group capable of stimulating the production of antibodies or sensitized lympho-cytes,playing an important role in antiviral immune ***,it can shed light on the development of diagnos-tic methods and novel ***,we have reviewed advances in animal coronavirus antigenic epitope research,aiming to provide a reference for the prevention and control of animal and human coronaviruses.

关键词： Animal coronavirus Antigen epitope B-cell epitope T-cell epitope Immune responses Vaccines

A multi-agent collaboration scheme for energy-efficient task scheduling in a 3D UAV-MEC space

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Frontiers of Information Technology & Electronic Engineering 2024年第6期25卷 824-838页

作者： Yang LI Ziling wEI Jinshu su Baokang ZHAO College of Computer National University of Defense TechnologyChangsha 410073China Academy of Military Sciences Beijing 100091China

Multi-access edge computing(MEC)presents computing services at the edge of networks to address the enormous processing requirements of intelligent *** to the maneuverability of unmanned aerial vehicles(UAVs),they can be used as temporal aerial edge nodes for providing edge services to ground users in ***,MEC environment is usually dynamic and *** is a challenge for multiple UAVs to select appropriate service ***,most of existing works study UAV-MEC with the assumption that the flight heights of UAVs are fixed;i.e.,the flying is considered to occur with reference to a two-dimensional plane,which neglects the importance of the *** this paper,with consideration of the co-channel interference,an optimization problem of energy efficiency is investigated to maximize the number of fulfilled tasks,where multiple UAVs in a threedimensional space collaboratively fulfill the task computation of ground *** the formulated problem,we try to obtain the optimal flight and sub-channel selection strategies for UAVs and schedule strategies for *** on the multi-agent deep deterministic policy gradient(MADDPG)algorithm,we propose a curiosity-driven and twin-networks-structured MADDPG(CTMADDPG)algorithm to solve the formulated *** uses the inner reward to facilitate the state exploration of agents,avoiding convergence at the sub-optimal ***,we adopt the twin critic networks for update stabilization to reduce the probability of q value *** simulation results show that CTMADDPG is outstanding in maximizing the energy efficiency of the whole system and outperforms the other benchmarks.

关键词： Multi-access edge computing Multi-agent reinforcement learning Unmanned aerial vehicles Task scheduling

Electrical stimulation with polypyrrole-coated polycaprolactone/silk fibroin scaffold promotes sacral nerve regeneration by modulating macrophage polarisation

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Biomaterials Translational 2024年第2期5卷 157-174页

作者： Cheng H. Bai J. Zhou X. Chen N. Jiang q. Ren Z. Li X. su T. Liang L. Jiang w. wang Y. Peng J. Shang A. School of Medicine Nankai University Tianjin China Department of Neurosurgery Chinese PLA General Hospital Beijing China Institute of Orthopedics Chinese PLA General Hospital Beijing Key Lab of Regenerative Medicine in Orthopedics Key Laboratory of Musculoskeletal Trauma and War Injuries PLA Beijing China Co-innovation Center of Neuroregeneration Nantong University Jiangsu Province Nantong China Graduate School of Chinese PLA General Hospital Beijing China Department of Ultrasound Chinese PLA General Hospital Beijing China

Peripheral nerve injury poses a great threat to neurosurgery and limits the regenerative potential of sacral nerves in the neurogenic bladder. It remains unknown whether electrical stimulation can facilitate sacral nerve regeneration in addition to modulate bladder function. The objective of this study was to utilise electrical stimulation in sacra nerve crush injury with newly constructed electroconductive scaffold and explore the role of macrophages in electrical stimulation with crushed nerves. As a result, we generated a polypyrrole-coated polycaprolactone/silk fibroin scaffold through which we applied electrical stimulation. The electrical stimulation boosted nerve regeneration and polarised the macrophages towards the M2 phenotype. An in vitro test using bone marrow derived macrophages revealed that the pro-regenerative polarisation of M2 were significantly enhanced by electrical stimulation. Bioinformatics analysis showed that the expression of signal transducer and activator of transcriptions (STATs) was differentially regulated in a way that promoted M2-related genes expression. Our work indicated the feasibility of electricals stimulation used for sacral nerve regeneration and provided a firm demonstration of a pivotal role which macrophages played in electrical stimulation. © 2024, Chinese Medical Multimedia Press Co Ltd. All rights reserved.

关键词： electrical stimulation JAK-STAT signalling pathway macrophage polarisation peripheral nerve regeneration polypyrrole sacral nerve injury

Structures and ion transport mechanisms of plant high-affinity potassium transporters

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Molecular Plant 2024年第3期17卷 409-422页

作者： Jiangqin wang Yanping Luo Fan Ye Zhong Jie Ding Shao Jian Zheng Shuai qiao Yong wang Jiangtao Guo wei Yang Nannan su international Institutes of Medicine the Fourth Affiliated HospitalZhejang University School of MedicineYiwuZhejiang 322000China Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital Zhejiang University School of MedicineHangzhouZhejang 310058China State Key Laboratory of Plant Environmental Resilience College of Life SciencesZhejang UniversityHangzhouZhejang 310058China College of Life Sciences Zhejiang UniversityHangzhouZhejiang 310058China NHC and CAMS Key Laboratory of Medical Neurobiology MOE Frontier Science Center for Brain Science and Brain-machine IntegrationSchool of Brain Science and Brain MedicineZhejiang UniversityHangzhouZhejiang 310058China Nanhu Brain-computer Interface Institute Hangzhou.Zheiang 311100.China

Plant high-affinity K^(+) transporters(HKTs)mediate Na^(+) and K^(+) uptake,maintain Na^(+)/K^(+) homeostasis,and therefore play crucial roles in plant salt *** this study,we present cryoelectron microscopy structures of HKTs from two classes,classI HKT1;1 from Arabidopsis thaliana(AtHKT1;1)and class II HKT2;1 from Triticum aestivum(TaHKT2;1),in both Na^(+) -and K^(+) -bound states at 2.6-to 3.0-A ***1;1and TaHKT2;1function *** HKT subunit consists of four tan-dem domain units(D1-D4)with a repeated K^(+) -channel-like M-P-M *** each subunit,D1-D4 assemble into an ion conduction pore with a pseudo-four-fold *** both TaHKT2;1and AtHKT1;1 have only one putative Na^(+) ion bound in the selectivity filter with a similar coordination pattern,the two HKTs display different K^(+) binding modes in the ***2;1 has three K^(+) ions bound in the selec-tivity filter,but AtHKT1;1 has only two K^(+) ions bound in the filter,which has a narrowed external entrance due to the presence of a Ser residue in the first filter *** structures,along with compu-tational,mutational,and electrophysiological analyses,enable us to pinpoint key residues that are critical for the ion selectivity of *** findings provide new insights into the ion selectivity and ion transport mechanisms of plant HKTs and improve our understanding about how HKTs mediate plant salt tolerance and enhance crop growth.

关键词： HKTs structure ion selectivity mechanism salt tolerance