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A Residual Frequency Offset Estimation Method Based on range Migration Fitting

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Journal of Beijing Institute of Technology 2024年第2期33卷 103-110页

作者： Liting Zhang Hao Huan ran tao Xiaogang Tang School of Information and Electronics Beijing Institute of Technology School of Aerospace Information Space Engineering University

Recently, researchers have proposed an emitter localization method based on passive synthetic aperture. However, the unknown residual frequency offset(RFO) between the transmitter and the receiver causes the received Doppler signal to shift, which affects the localization accuracy. To solve this issue, this paper proposes a RFO estimation method based on range migration fitting. Due to the high frequency modulation slope of the linear frequency modulation(LFM)-modulation radar signal, it is not affected by RFO in range compression. Therefore, the azimuth time can be estimated by fitting the peak value position of the pulse compression in range direction.Then, the matched filters are designed under different RFOs. When the zero-Doppler time obtained by the matched filters is consistent with the estimated azimuth time, the given RFO is the real RFO between the transceivers. The simulation results show that the estimation error of azimuth distance does not exceed 20 m when the received signal duration is not less than 3 s, the pulse repetition frequency(PRF) of the transmitter radar signal is not less than 1 k Hz, the range detection is not larger than 1 000 km, and the signal noise ratio(SNR) is not less than –5 d B.

关键词： passive localization range migration fitting (RMF) residual frequency offset (RFO)

METTL5 promotes cell proliferation,invasion,and migration by up-regulating Toll-like receptor 8 expression in colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2006-2017页

作者： Ling-Shang Kong ran tao Yi-Fan Li Wen-Bin Wang Xue Zhao Department of General Surgery The Second Affiliated Hospital of Anhui Medical UniversityHefei 230001Anhui ProvinceChina Department of Vascular Surgery The Second Affiliated Hospital of Anhui Medical UniversityHefei 230002Anhui ProvinceChina Department of General Surgery The First Affiliated Hospital of Anhui Medical UniversityHefei 230001Anhui ProvinceChina Anhui Public Health Clinical Center Hefei 230012Anhui ProvinceChina Department of Scientific Research Anhui Public Health Clinical CenterHefei 230012Anhui ProvinceChina Department of Scientific Research The First Affiliated Hospital of Anhui Medical UniversityHefei 230001Anhui ProvinceChina

BACKGROUND N6-methyladenosine(m6A)modification represents the predominant alteration found in eukaryotic messenger RNA and plays a crucial role in the progression of various tumors.However,despite its significance,the comprehensive investigation of METTL5,a key m6A methyltransferase,in colorectal cancer(CRC)remains limited.AIM To investigate the role of METTL5 in CRC.METHODS We assessed METTL5 expression levels in clinical samples obtained from CRC patients as well as in CRC cell lines.To elucidate the downstream targets of METTL5,we performed RNA-sequencing analysis coupled with correlation analysis,leading us to identify Toll-like receptor 8(TLR8)as a potential downstream target.In vitro functional assessments of METTL5 and TLR8 were conducted using CCK-8 assays,scratch assays,as well as assays measuring cell migration and invasion.RESULTS Our findings reveal a pronounced upregulation of METTL5 expression in both CRC cells and tissues,which correlated significantly with an unfavorable prognosis.In vitro experiments unequivocally demonstrated the oncogenic role of METTL5,as evidenced by its promotion of CRC cell proliferation,invasion,and migration.Notably,we identified TLR8 as a downstream target of METTL5,and subsequent down-regulation of TLR8 led to a significant inhibition of CRC cell proliferation,invasion,and tumor growth.CONCLUSION The heightened expression of METTL5 in CRC is strongly associated with clinicopathological features and a poor prognosis,thereby underscoring its potential utility as a critical marker for facilitating early diagnosis and prognostication in CRC.

关键词： METTL5 Toll-like receptor 8 Colorectal cancer

Effects of in-situZrB_2 nanoparticles and scandium on microstructure and mechanical property of 7N01 aluminum alloy

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Journal of Rare Earths 2024年第3期42卷 612-620,I0007页

作者： Xizhou Kai Yuhui Wang Ruikun Chen Yanjie Peng Anjun Shi ran tao Xiangfeng Liang Guirong Li Gang Chen Xiaojing Xu Yutao Zhao School of Material Science and Engineering Jiangsu UniversityZhenjiang212013China Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang212013China

In this study, the in-situ synthesized ZrB_(2) nanoparticles and rare earth Sc were introduced to enhance the strength and ductility of 7N01 aluminum alloy, via the generation of high-melting and uniform nanodispersoids. The microstructure and mechanical property evolution of the prepared composites and the interaction between ZrB_(2) and Sc were studied in detail. The microstructure investigation shows that the introduction of rare earth scandium(Sc) can promote the distribution of ZrB_(2) nanoparticles, by improving their wettability to the Al melt. Meanwhile, the addition of rare earth Sc also modifies the coarse Al Zn Mg Mn Fe precipitated phases, refines the matrix grains and generates high-melting Al_3(Sc,Zr)/Al_3Sc nanodispersoids. Tensile tests of the composites show that with the combinatorial introduction of ZrB_(2) and Sc, the strength and ductility of the composites are improved simultaneously compared with the corresponding 7N01 alloy, ZrB_(2) /7N01 composite and Sc/7N01 alloy. And the optimum contents of ZrB_(2) and Sc are 3 wt% and 0.2 wt% in this study. The yield strength, ultimate strength and elongation of(3 wt% ZrB_(2) +0.2 wt% Sc)/7N01 composite are 477 MPa, 506 MPa and 9.8%, increased about 18.1%, 12.2%and 38% compared to 7N01 alloy. Furthermore, the cooperation strengthening mechanisms of ZrB_(2) and Sc are also discussed.

关键词： 7N01 aluminum alloy In-situ ZrB_(2)nanoparticles Rare earth Sc Microstructure Mechanical property Mechanism

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Formation mechanism of Fe-based amorphous powders produced by spark erosion

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Journal of Materials Science & Technology 2024年第3期170卷 33-46页

作者： Chekai Liu ran Li Jiazi Bi Ding Ma Xiaobin Liu tao Zhang School of Materials Science and Engineering Key Laboratory of Aerospace Materials and Performance(Ministry of Education)Beihang UniversityBeijing 100191China

Spark erosion is a convenient,flexible,and low-cost method to quickly produce fine powders of metals,alloys,and semiconductors in size ranging from nearly a hundred micrometers to submicrometer by repetitive spark discharges.Due to the complexity of the powder-forming journey,normally accompanied by high temperature,high pressure,decomposition,diffusion and rapid quenching caused by discharge plasma,the mechanisms of powder formation and possible contaminant infiltration are still controversial,posing a significant challenge to control particle size and chemical composition of the powder produced by this method.In this study,Fe-based amorphous powders in different particle-size distributions with high sphericity were fabricated by spark erosion under different discharge-energy conditions.The max-imum particle size of the resultant powders can be correlated with discharge parameters,crater depth,and crater radius,respectively.A multi-ring-breakup model is proposed to reveal the particle-size distribution of the powder formed from the electrode melt under a single-pulse discharge.Furthermore,a dielectric-element infiltration model is provided to quantitatively evaluate the infiltration mass ratio of the contaminant elements,stemming from the decomposed products of dielectric liquid,in the resultant powder with different particle sizes.The models verified through the experimental data are significant for the development of high-performance fine Fe-based amorphous powder with controlled particle size and chemical composition.

关键词： Amorphous alloy Particle Spark erosion Infiltration Modeling

Chemoradiotherapy plus tislelizumab for mismatch repair proficient rectal cancer with supraclavicular lymph node metastasis:A case report

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2219-2224页

作者： Wen-tao Zhong Yuan Lv Qian-Yu Wang ran An Gang Chen Jun-Feng Du The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of General Surgery The 7^(th)Medical Center of PLA General HospitalBeijing 100700China Department of Pathology The 7^(th)Medical Center of PLA General HospitalBeijing 100700China

BACKGROUND According to the latest report,colorectal cancer is still one of the most prevalent cancers,with the third highest incidence and mortality worldwide.Treatment of advanced rectal cancer with distant metastases is usually unsatisfactory,especially for mismatch repair proficient(pMMR)rectal cancer,which leads to poor prognosis and recurrence.CASE SUMMARY We report a case of a pMMR rectal adenocarcinoma with metastases of multiple lymph nodes,including the left supraclavicular lymph node,before treatment in a 70-year-old man.He received full courses of chemoradiotherapy(CRT)followed by 4 cycles of programmed death 1 inhibitor Tislelizumab,and a pathologic complete response(pCR)was achieved,and the lesion of the left supraclavicular lymph node also disappeared.CONCLUSION pMMR advanced rectal cancer with preserved intact distant metastatic lymph nodes may benefit from full-course CRT combined with immunotherapy.

关键词： Rectal cancer Metastasis Chemoradiotherapy Immunotherapy Prognosis Case report

One-step conversion of methane and formaldehyde to ethanol over SA-FLP dual-active-site catalysts: A DFT study

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Chinese Chemical Letters 2024年第4期35卷 544-548页

作者： tao Ban Xi-Yang Yu Hai-Kuo Tian Zheng-Qing Huang Chun-ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China

One-step conversion of methane and formaldehyde into ethanol is a 100% atom-efficient process for carbon resources utilization and environment protection but still faces eminent challenges due to the lacking of efficient catalysts. Therefore, developing active and stable catalysts is crucial for the co-conversion of methane and formaldehyde. Herein, twelve kinds of “Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual-active-site catalysts are designed for the direct conversion of methane and formaldehyde to ethanol based on density functional theory(DFT) calculations and microkinetic simulations. The results show that the SA-FLP dual active sites can simultaneously activate methane at the SA site and activate formaldehyde at the FLP site. Among the twelve designed SA-FLP catalysts, Fe1-FLP shows the best performance in the co-conversion of methane and formaldehyde to ethanol with the rate-determining barrier of 1.15 e V.Ethanol is proved as the main product with the turnover frequency of 1.32 × 10^(-4)s^(-1)at 573 K and 3 bar.This work provides a universal strategy to design dual active sites on metal oxide materials and offers new insights into the effective conversion of methane and formaldehyde to desired C_(2) chemicals.

关键词： Single-atom Frustrated Lewis pairs Methane conversion Dual active sites Ethanol synthesis

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Transparent micropatterned conductive films based on highlyordered nanowire network

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Nano Research 2024年第5期17卷 4288-4297页

作者： Xin-ran Zhang Hai-tao Deng Xu Zeng Yi-Lin Wang Peng Huang Xiao-Sheng Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Transparent conductive films that are based on nanowire networks are essential to construct flexible,wearable,and even stretchable electronics.However,large-scale precise micropatterning,especially with regard to the controllability of the organizing orientation of nanowires,is a critical challenge.Herein,we proposed a liquid film rupture self-assembly approach for manufacturing transparent conductive films with microstructure arrays based on a highly ordered nanowire network.The large-scale microstructure conductive films were fabricated through air-liquid interface self-assembly and liquid film rupture self-assembly.Six typical micropattern morphologies,including square,hexagon,circle,serpentine,etc.,were prepared to reveal the universal applicability of the proposed approach.The homogeneity and controllability of this approach were verified for multiple assemblies.With the assembly cycles increasing,the optical transmittance decreases slightly.In addition,theoretical model analysis is carried out,and the analytical formula of the speed of the film moving with the surface tension and the density of the liquid film is presented.Finally,the feasibility of this approach for piezoresistive strain sensors is verified.This fabrication approach demonstrated a cost-effective and efficient method for precisely arranging nanowires,which is useful in transparent and wearable applications.

关键词： flexible electronics transparent conductive network micropatterning nanowires micro electromechanical systems(MEMS)

Blind adaptive identification and equalization using bias-compensated NLMS methods

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Science China(Information Sciences) 2022年第5期65卷 184-195页

作者： Zhen ZHANG Lijuan JIA ran tao Yue WANG School of Information and Electronics Beijing Institute of Technology

In this paper, two new blind adaptive identification and equalization algorithms based on second-order statistics are proposed. We consider a practical case where the noise statistics of each transmission channel is unknown. Resorting to the technique of antennas array, a single-input double-output channel can be obtained. We further convert the problem of blind identification into an errors-in-variables(EIV)parameter estimation problem, then we apply the normalized least-mean squares(NLMS) algorithms to tackle the problem. To improve the performance of the NLMS algorithms, we also develop a variable stepsize NLMS(VSS-NLMS) algorithm that ensures the stability of the algorithm and faster convergence speed at the beginning of the iterations process. Under various practical scenarios, noise affects transmission channels;it is necessary to estimate the variance and remove the bias. By modifying the cost function, we present a bias-compensated NLMS(BC-NLMS) algorithm and a bias-compensated NLMS algorithm with variable step-size(BC-VSS-NLMS) to eliminate the bias. The proposed algorithms estimate the variances of the noise online, and therefore, the noise-induced bias can be removed. The estimate of the channel characteristics is available for equalization. Simulation results are presented to demonstrate the performance of the proposed algorithms.

关键词： blind adaptive identification equalization normalized least mean squares algorithm bias compensation errors-in-variables

Multi-stage Defender-Attacker-Defender Model for Distribution System Resilience Enhancement in Ice Storms with Line Hardening,Mobile Device and Repair Crew Dispatching

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1103-1118页

作者： ran tao Dongmei Zhao Haoxiang Wang Xuan Xia School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China State Grid Shaoxing Power Supply Company Shaoxing 312000China

This paper proposes a co-optimal strategy using line hardening,mobile devices(mobile ice-melting device,mobile emergency generator,mobile energy storage system),and repair crew dispatching to improve distribution system resilience during ice storms.A multi-stage defender-attacker-defender model is established to take into account interactions and coupling relationships between different measures.In our proposed model,ice storms will attack the distribution and transportation system in a worst-case scenario,affecting system performance from various perspectives.Corresponding to the different operating states in the distribution system affected by ice storms,aiming at minimizing the weighted load shedding value,this paper applies various measures to different stages to improve the response and defense capabilities to ice storms and realize restoration of the distribution system ultimately.The nested column-and-constraint generation algorithm is used to solve the model efficiently.The effectiveness of the proposed model and solution method for enhancing the distribution system resilience is verified on the modified IEEE 33-bus distribution system and modified realworld zone of Caracas 141-bus distribution system.

关键词： Defender-attacker-defender model distribution system resilience ice storm line hardening mobile device repair crew