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Journal of Oceanology and limnology 2024年第3期42卷 709-714页

作者： Xudong ZHANG xiaofeng li Key Laboratory of Ocean Observation and Forecasting Key Laboratory of Ocean Circulation and WavesInstitute of OceanologyChinese Academy of SciencesQingdao 266071China

Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global *** remote sensing images have played an essential role in studying ISWs,they mainly exploit two-dimensional image ***,with the launch of the surface water ocean topography(SWOT)satellite on December 16,2022,a unique opportunity has emerged to capture wide-swath three-dimensional ISW-induced sea surface *** this study,we examine ISWs in the Andaman Sea using data from the Ka-band Radar Interferometer(KaRIN),a crucial sensor onboard *** not only provides backscattering satellite images but also employs synthetic aperture interferometry techniques to retrieve wide-swath two-dimensional sea surface height *** observations in the Andaman Sea revealed the presence of ISWs characterized by dark-bright strips and surface elevation *** surface soliton has an amplitude of 0.32 m,resulting in an estimation of ISW amplitude of approximately 60 *** contrast to traditional two-dimensional satellite images or nadir-looking altimetry data,the SWOT mission’s capability to capture threedimensional sea surface information represents a significant *** breakthrough holds substantial promise for ISW studies,particularly in the context of ISW amplitude inversion.

关键词： internal solitary wave(ISW) surface water ocean topography(SWOT) altimeter

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Effect of Direct Aging on Corrosion Behavior of AlSi10Mg Alloy Fabricated by Laser Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 266-282页

作者： Zhen Zhang Zhanyong Zhao xiaofeng li Beibei Wang Peikang Bai Shanxi Key Laboratory of Controlled Metal Solidification and Precision Manufacturing School of Materials Science and EngineeringNorth University of ChinaTaiyuan030051China Technical Center Taiyuan Iron and Steel(Group)Co.LtdTaiyuan030003China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Effect of direct aging of 170℃on corrosion behavior of laser powder bed fused AlSi10Mg(LPBF-AlSi10Mg)was studied by microstructure analysis,electrochemical analysis and X-ray photoelectron *** results show that direct aging of 170℃has little effect on melt pool and Si cellular structure,but promotes the precipitation of nano-Si particles and releases the residual *** increasing aging time from 0 to 4 h to 24 h,the corrosion property of the LPBF-AlSi10Mg is deteriorated,which is evidenced by increased corrosion current density and decreased pitting potential and polarization *** increasing the aging time,the thickness of the oxide film formed on surface of the LPBF-AlSi10Mg *** Si content of the oxide film of the sample aging for 4 h is the lowest,9.42 at.%,and it is the highest,18.62 at.%,for the sample aging for 24 *** electrochemical noise analysis reveals that the middle-frequency contribution of the Hilbert spectrum is responsible for the deteriorated corrosion performance,which corresponds to metastable pitting initiated by nano-Si particles.

关键词： Laser powder bed fusion AlSi10Mg Direct aging Corrosion

Alterations in expression and localization of POMGNT1 in the APP/PS1 mouse model of Alzheimer’s disease

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Genes & Diseases 2024年第5期11卷 55-58页

作者： Hanxiao Jiang Yuxue Feng Xia Hao Guiqiong He xiaofeng li Department of Neurology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 401336China Chongqing Key Laboratory of Neurobiology Chongqing Medical UniversityChongqing 400016China Department of Anatomy Chongqing Medical UniversityChongqing 400016China Department of Neurology The Fifth People’s Hospital of ChongqingChongqing 400062China

Alzheimer’s disease(AD)is a complex and progressive neurodegenerative disorder that causes dementia in the aging *** of the characteristic pathologic hallmarks of AD is the senile plaques,composed of the accumulation of *** b-amyloid results from the cleavage of transmembrane b-amyloid precursor protein(APP)by b-secretases and g-secretases,sequentially.O-mannosylation was found essential for the normal function of APP in Saccharomyces cerevisiae.1 Protein Olinked mannose b1,2-N-acetyl-glucosaminyltransferase 1(POMGNT1)is a glycosyltransferase crucial for the elongation of O-mannosyl glycans and catalyzes the transfer of Nacetylglucosamine from uridine 50-diphosphate-N-acetylglucosamine to O-mannose of glycoproteins.

关键词： APP/PS1 Alzheimer amyloid

FPSblo:A Blockchain Network Transmission Model Utilizing Farthest Point Sampling

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Computers, Materials & Continua 2024年第2期78卷 2491-2509页

作者： Longle Cheng Xiru li Shiyu Fang Wansu Pan He Zhao Haibo Tan xiaofeng li Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230026China

Peer-to-peer(P2P)overlay networks provide message transmission capabilities for blockchain *** data transmission efficiency in P2P networks can greatly enhance the performance of blockchain ***,traditional blockchain P2P networks face a common challenge where there is often a mismatch between the upper-layer traffic requirements and the underlying physical network *** mismatch results in redundant data transmission and inefficient routing,severely constraining the scalability of blockchain *** address these pressing issues,we propose FPSblo,an efficient transmission method for blockchain *** inspiration for FPSblo stems from the Farthest Point Sampling(FPS)algorithm,a well-established technique widely utilized in point cloud image *** this work,we analogize blockchain nodes to points in a point cloud image and select a representative set of nodes to prioritize message forwarding so that messages reach the network edge quickly and are evenly ***,we compare our model with the Kadcast transmission model,which is a classic improvement model for blockchain P2P transmission networks,the experimental findings show that the FPSblo model reduces 34.8%of transmission redundancy and reduces the overload rate by 37.6%.By conducting experimental analysis,the FPS-BT model enhances the transmission capabilities of the P2P network in blockchain.

关键词： Blockchain P2P networks scalability farthest point sampling

Spatiotemporal Changes of Snow Depth in Western Jilin,China from 1987 to 2018

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Chinese Geographical Science 2024年第2期34卷 357-368页

作者： WEI Yanlin li xiaofeng GU lingjia ZHENG Zhaojun ZHENG Xingming JIANG Tao Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchun 130102China College of Electronic Science and Engineering Jilin UniversityChangchun 130012 National Meteorological Satellite Meteorological Center Beijing 100081China

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming ***,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse ***,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD *** results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/*** snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air *** correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and *** March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo ***,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.

关键词： snow cover snow depth(SD) climate changes passive microwave(PMW) western Jilin,China

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Low Loss and Low EMI Noise Trench IGBT with Shallow Emitter Trench Controlled P-Type Dummy Region

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Chinese Journal of Electronics 2024年第2期33卷 326-335页

作者： Jinping ZHANG xiaofeng li Rongrong ZHU Kang WANG Bo ZHANG State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China (UESTC) Institute of Electronic and Information Engineering of UESTC in Guangdong

A novel trench insulated gate bipolar transistor（TIGBT） with a shallow emitter trench controlled P-type dummy region（STCP-TIGBT） is *** with the conventional TIGBT with floating P-type dummy region（CFP-TIGBT） and TIGBT with floating P-type dummy region and normally on hole path（HFPTIGBT）,the proposed STCP structure not only speeds up the extraction of excessive holes in the turn-off process but also reduces the Miller plateau charge(Qgc).Therefore,both the power loss and electromagnetic interference（EMI） noise are significantly *** results show that the Qgcof the proposed device is only 501 nC/cm2,which is reduced by 58.5% and 26.4% when compared to the CFP-TIGBT and HFP-TIGBT,*** same on-state voltage drop(Vceon) of 1.02 V,the turn-off loss(Eoff) of the proposed device is 13.49 mJ/cm2,which is 64.6%and 67.6% less than those of the CFP-TIGBT and HFP-TIGBT,***,the reverse recovery dVak/dt of the freewheeling diode at same turn-on loss(Eon) of 31.8 mJ/cm2for the proposed STCP-TIGBT is only 2.15 kV/μs,which is reduced by 91.3% and 57.2% when compared to 24.69 kV/μs and 5.02 kV/μs for the CFP-TIGBT and HFPTIGBT,*** reduced dV/dt significantly suppresses the electromagnetic interference noise generated by the proposed device.

关键词： Insulated gate bipolar transistors Electrodes Annealing Simulation Electromagnetic interference Noise Voltage

A Multi-Constraint Path Optimization Scheme Based on Information Fusion in Software Defined Network

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Computers, Materials & Continua 2024年第4期79卷 1399-1418页

作者： Jinlin Xu Wansu Pan Longle Cheng Haibo Tan Munan Yuan xiaofeng li Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230026China

The existingmultipath routing in Software Defined Network (SDN) is relatively blind and inefficient, and there is alack of cooperation between the terminal and network sides, making it difficult to achieve dynamic adaptationof service requirements and network resources. To address these issues, we propose a multi-constraint pathoptimization scheme based on information fusion in SDN. The proposed scheme collects network topology andnetwork state information on the network side and computes disjoint paths between end hosts. It uses the FuzzyAnalytic Hierarchy Process (FAHP) to calculate the weight coefficients of multiple constrained parameters andconstructs a composite quality evaluation function for the paths to determine the priority of the disjoint paths. TheSDN controller extracts the service attributes by analyzing the packet header and selects the optimal path for flowrule forwarding. Furthermore, the service attributes are fed back to the path composite quality evaluation function,and the path priority is dynamically adjusted to achieve dynamic adaptation between service requirements andnetwork status. By continuously monitoring and analyzing the service attributes, the scheme can ensure optimalrouting decisions in response to varying network conditions and evolving service demands. The experimentalresults demonstrated that the proposed scheme can effectively improve average throughput and link utilizationwhile meeting the Quality of Service (QoS) requirements of various applications.

关键词： SDN multi-constraint path information fusion FAHP

The Geology, Fluid Inclusions, and O-S Isotopes of the Mibei Gold Deposit, Hunan Province, Southern China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 992-1006页

作者： XUE Wenhao liANG Yayun li xiaofeng li Mingyi XIE Wenbo PENG Xue XIA Rui HE Hongsheng XIAO Jincheng School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Geophysical and Geochemical Survey Institute of Hunan Changsha 410116China New Geological Energy Exploration and Development Engineering Technology Research Center of Hunan Changsha 410116China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China Comprehensive Survey Command Center for Natural Resources China Geological SurveyBeijing 100055China

The Mibei gold deposit,located in the southwestern part of the Xuefengshan uplift zone,the middle section of the Jiangnan orogenic belt in southern China,has estimated gold resources of approximately seven *** deposit is primarily a quartz vein-type gold deposit,with ore bodies occurring mainly within Neoproterozoic *** main metallic minerals in the ore are pyrite,chalcopyrite,and *** this study,the petrography and microthermometry of ore-forming fluid inclusions,oxygen isotopes of gold-bearing quartz,and sulfur isotopes of goldbearing sulfides and arsenopyrite were *** types of fluid inclusions were identified:type Ⅰa three-phase inclusions comprising vapor and two phases of liquids(V_(CO_(2))+L_(CO_(2))+L_(H2O)),type Ⅰb two-phase liquids(L_(CO_(2))+L_(H2O)),typeⅡ two-phase vapor-rich inclusions(V/V+L> 50%),and type Ⅲ pure liquid *** Ⅰ inclusions were heated uniformly to the liquid phase,type Ⅱ inclusions were heated uniformly to the gas phase,and type Ⅲ inclusions were heated without *** general,the temperature range of homogenization to liquid phase of fluid inclusions in the Mibei gold deposit is 204-227℃.The salinity of the inclusion ranges from 4.6 to 12.2 wt% NaCl *** δ~(18)O_(SMOW) of gold-bearing quartz varies from 16.9‰ to 17.5‰.The δ~(18)O_(H2O) of gold-bearing quartz are varied from 6.5‰ to 7.5‰.The δ~(34)S values of gold-bearing pyrite range from 1.7‰ to 6.8‰.The δ~(34)S values of gold-bearing arsenopy rite range from 5.6%o to 5.9‰.Theδ~(34)S values of pyrite from wall rocks slate range from 6.4‰ to 11.6‰.This evidence implies that the ore-forming fluids of the Mibei gold deposit originated from magmatic-hydrothermal processes,mixing with minor S from the surrounding *** with the evolution of the Jiangnan orogenic belt,due to the magmatic and tectonic activities of the Xuefengshan uplift during the Caledonian period,the fault seal mechanism controlled the ore-forming p

关键词： ore-forming fluid ore genesis Mibei gold deposit Xuefengshan uplift zone Jiangnan orogenic belt

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Decoding m^(6)A mRNA methylation by reader proteins in liver diseases

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Genes & Diseases 2024年第2期11卷 711-726页

作者： lijiao Sun Xin Chen Sai Zhu Jianan Wang Shaoxi Diao Jinyu liu Jinjin Xu xiaofeng li Yingyin Sun Cheng Huang Xiaoming Meng Xiongwen Lv Jun li Inflammation and Immune Mediated Diseases Laboratory of Anhui Province Anhui Institute of Innovative DrugsSchool of PharmacyAnhui Medical UniversityHefeiAnhui 230032China The Key Laboratory of Anti-inflammatory and Immune Medicines Anhui Medical UniversityMinistry of EducationHefeiAnhui 230032China Institute for liver Diseases of Anhui Medical University ILD-AMUAnhui Medical UniversityHefeiAnhui 230032China Department of Nephropathy The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China Department of Oncology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230032China

N6-methyladenosine(m^(6)A)is a dynamic and reversible epigenetic *** the most prevalent internal post-transcriptional modification in eukaryotic RNA,it participates in the regulation of gene expression through various mechanisms,such as mRNA splicing,nuclear export,localization,translation efficiency,mRNA stability,and structural *** involvement of m^(6)A in the regulation of gene expression depends on the specific recognition of m^(6)A-modified RNA by reader *** the pathogenesis and treatment of liver disease,studies have found that the expression levels of key genes that promote or inhibit the development of liver disease are regulated by m^(6)A modification,in which abnormal expression of reader proteins determines the fate of these gene *** this review,we introduce m^(6)A readers,summarize the recognition and regulatory mechanisms of m^(6)A readers on mRNA,and focus on the biological functions and mechanisms of m^(6)A readers in liver cancer,viral hepatitis,non-alcoholic fatty liver disease(NAFLD),hepatic fibrosis(HF),acute liver injury(Ali),and other liver *** information is expected to be of high value to researchers deciphering the links between m^(6)A readers and human liver diseases.

关键词： IGF2BPs liver diseases m^(6)A modification m^(6)A reader mRNA metabolism YTH domain protein

Ultra-wide band gap and wave attenuation mechanism of a novel star-shaped chiral metamaterial

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1261-1278页

作者： Shuo WANG Anshuai WANG Yansen WU xiaofeng li Yongtao SUN Zhaozhan ZHANG Qian DING G.D.AYALEW Yunxiang MA Qingyu liN Department of Mechanics Tianjin University Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin University State Key Laboratory of Metastable Materials Science and Technology Yanshan University

A novel hollow star-shaped chiral metamaterial(SCM) is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial, exhibiting a wide band gap over 1 500 Hz. To broaden the band gap,solid single-phase and two-phase SCMs are designed and simulated, which produce two ultra-wide band gaps(approximately 5 116 Hz and 6 027 Hz, respectively). The main reason for the formation of the ultra-wide band gap is that the rotational vibration of the concave star of two novel SCMs drains the energy of an elastic wave. The impacts of the concave angle of a single-phase SCM and the resonator radius of a two-phase SCM on the band gaps are studied. Decreasing the concave angle leads to an increase in the width of the widest band gap, and the width of the widest band gap increases as the resonator radius of the two-phase SCM increases. Additionally,the study on elastic wave propagation characteristics involves analyzing frequency dispersion surfaces, wave propagation directions, group velocities, and phase velocities. Ultimately, the analysis focuses on the transmission properties of finite periodic structures. The solid single-phase SCM achieves a maximum vibration attenuation over 800, while the width of the band gap is smaller than that of the two-phase SCM. Both metamaterials exhibit high vibration attenuation capabilities, which can be used in wideband vibration reduction to satisfy the requirement of ultra-wide frequencies.

关键词： metamaterial ultra-wide band gap wave propagation vibration suppression O421 + .5 74H45