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Multi-modal imaging for the diagnosis of spontaneous visceral artery dissection:A case report

World Journal of Gastrointestinal Surgery 2024年第5期16卷 1430-1435页

作者： yang pu yan Luo Department of Medical Ultrasound West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Spontaneous visceral artery dissection(SVAD)is a rare condition that affects the visceral arteries,such as the celiac,superior mesenteric,and inferior mesenteric arteries,without involving the *** ischemia or hemorrhage from vessel rupture can occur in SVAD;therefore,prompt detection and management is ***-enhanced computed tomography(CECT)has been used to diagnose most of the previous cases,but few studies have explored the potential of contrast-enhanced ultrasound(CEUS)for early detection of this *** SUMMARY A 53-year-old male presented with complaints of poor appetite and abnormal liver function for the past 6 *** had previously undergone transabdominal splenectomy,esophagogastric devascularization,and cholecystectomy for gallstones and severe portal *** ultrasound was performed in our department to assess liver *** abnormal hepatic artery spectrum was observed,and dissection involving both the celiac artery and the common hepatic artery was observed.A CEUS was then performed and clearly showed the entry site of the intimal tear and the false lumen,and dissection was subsequently confirmed by *** patient was asymptomatic;therefore,treatment to control the blood pressure was provided,and follow-up was *** 6 months of follow-up,the celiac artery was found to be dilated with an adherent thrombus visible in the wall,and the common hepatic artery was occluded with the presence of *** these findings,no significant changes in liver function were *** Multi-modal imaging is effective in diagnosing SVAD,and conservative treatment is a choice for asymptomatic patients.

关键词： Spontaneous visceral artery dissection Celiac artery dissection Contrastenhanced computed tomography Contrast-enhanced ultrasound Case report

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A Reliable Iteration Algorithm for One-Bit Compressive Sensing on the Unit Sphere

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 801-822页

作者： yan-cheng LU Ning BI An-hua wan School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

The one-bit compressed sensing problem is of fundamental importance in many areas,such as wireless communication,statistics,and so ***,the optimization of one-bit problem coustrained on the unit sphere lacks an algorithm with rigorous mathematical proof of convergence and *** this paper,an iteration algorithm is established based on difference-of-convex algorithm for the one-bit compressed sensing problem constrained on the unit sphere,with iterating formula■,where C is the convex cone generated by the one-bit measurements andη_(1)>η_(2)>1/*** new algorithm is proved to converge as long as the initial point is on the unit sphere and accords with the measurements,and the convergence to the global minimum point of the l_(1)norm is discussed.

关键词： one-bit compressed sensing difference of convex algorithm iteration algorithm ■1-minimization

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Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

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Petroleum Science 2024年第3期21卷 1765-1779页

作者： yan-Zhong Liang Bai-Lu Teng wan-Jing Luo School of Energy Resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

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Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-Liang pu yan-Lin Ye Jian-Ling Lou Jia-Hao Chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control *** proposed digital system can be combined with a conventional analog data acquisition system to provide more *** performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

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Clustering for Bivariate Functional Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 613-629页

作者： Shi-yun CAO yan-qiu ZHOU yan-ling wan Tao ZHANG School of Science Guangxi University of Science and TechnologyLiuzhou 545006China School of Marxism Guangxi University of Science and TechnologyLiuzhou 545006China Key Laboratory of Intelligent Information Processing and Graph Processing Guangxi University of Science and TechnologyLiuzhou 545006China

In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each *** k-centres surface clustering method based on marginal functional principal component analysis is proposed for the bivariate functional data,and a novel clustering criterion is presented where both the random surface and its partial derivative function in two directions are *** addition,we also consider two other clustering methods,k-centres surface clustering methods based on product functional principal component analysis or double functional principal component *** results indicate that the proposed methods have a nice performance in terms of both the correct classification rate and the adjusted rand *** approaches are further illustrated through empirical analysis of human mortality data.

关键词： bivariate functional data -centres surface clustering functional principal component analysis partial derivative function

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Recent Advances in Mechanistic Understanding of Metal-Free Carbon Thermocatalysis and Electrocatalysis with Model Molecules

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Nano-Micro Letters 2024年第7期16卷 74-97页

作者： Wei Guo Linhui Yu Ling Tang yan wan yangming Lin CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021People’s Republic of China

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and *** the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction ***,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental *** this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon *** both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically *** with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular ***,the outlook of model carbon catalysis has also been proposed in this work.

关键词： Metal-free carbon catalysts Model catalyst Electrocatalysis Active site Reaction mechanisms

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Machine learning assisted adsorption performance evaluation of biochar on heavy metal

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 29-42页

作者： Qiannan Duan Pengwei yan Yichen Feng Qianru wan Xiaoli Zhu Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi’an710127China Department of Environment Science Shaanxi Normal UniversityXi’an710062China

Heavy metals(HMs)represent pervasive and highly toxic environmental pollutants,known for their long latency periods and high toxicity levels,which pose significant challenges for their removal and ***,the removal of heavy metals from the environment is crucial to ensure the water *** materials,known for their intricate pore structures and abundant oxygen-containing functional groups,are frequently harnessed for their effectiveness in mitigating heavy metal ***,conventional tests for optimizing biochar synthesis and assessing their heavy metal adsorption capabilities can be both costly and *** address this challenge,this paper proposes a data-driven machine learning(ML)approach to identify the optimal biochar preparation and adsorption reaction conditions,with the ultimate goal of maximizing their adsorption *** utilizing a data set comprising 476 instances of heavy metal absorption by biochar,seven classical integrated models and one stacking model were trained to rapidly predict the efficiency of heavy metal adsorption by *** predictions were based on diverse physicochemical properties of biochar and the specific adsorption reaction *** results demonstrate that the stacking model,which integrates multiple algorithms,allows for training with fewer samples to achieve higher prediction accuracy and improved generalization ability.

关键词： Machine learning Biochar Heavy metal Adsorption efficiency

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Application of ultrasonic fatigue technology in very-high-cycle fatigue testing of aviation gas turbine engine blade materials:A review

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Science China(Technological Sciences) 2024年第5期67卷 1317-1363页

作者： ZHAO JiuCheng wan Jie ZHANG ShiZhong yan ChuLiang ZHAO HongWei Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin UniversityChangchun 130025China School of Mechanical&Aerospace Engineering Jilin UniversityChangchun 130025China Chongqing Research Institute of Jilin University Chongqing401120China School of Aeronautic Science and Engineering Beihang UniversityBeijing 102206China

The need for very-high-cycle fatigue(VHCF)testing up to 1010cycles of aviation gas turbine engine blade materials under combined mechanical loads and complex environments has encouraged the development of VHCF testing instrumentation and *** article begins with a comprehensive review of the existing available techniques that enable VHCF *** advances in ultrasonic fatigue testing(UFT)techniques are highlighted,containing their new capabilities and methods for single load,multiaxial load,variable amplitude fatigue,and combined cycle *** techniques for conducting UFT in high-temperature,humid environments,and corrosive environments are *** developments in mechanical loading and environmental building techniques provide the possibility of laboratory construction for real service conditions of blade *** techniques that can be used for in situ monitoring of VHCF damage are *** issues in the UFT field are presented,and countermeasures are ***,the existing problems and future trends in the field are briefly described.

关键词： aviation gas turbine engine blade materials ultrasonic fatigue very-high-cycle fatigue high-temperature complex stress in situ testing

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Persistent organic pollutants in global surface soils:Distributions and fractionations

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Environmental Science and Ecotechnology 2024年第2期18卷 13-27页

作者： Yi-Fan Li Shuai Hao wan-Li Ma pu-Fei yang Wen-Long Li Zi-Feng Zhang Li-yan Liu Robie WMacdonald International Joint Research Center for Persistent Toxic Substances(IJRC-PTS) State Key Laboratory of Urban Water Resource and EnvironmentHarbinInstitute of TechnologyHarbin150090China International Joint Research Center for Arctic Environment and Ecosystem(IJRC-AEE) Polar AcademyHarbin Institute of Technology(PA-HIT)Harbin150090China Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem(HPKL-PEE) Harbin150090China IJRC-PTS-NA TorontoONM2J 3N8Canada College of the Environment and Ecology Xiamen UniversityXiamenChina Institute of Ocean Sciences Department of Fisheries and OceansP.O.Box 6000SidneyBCV8L 4B2Canada Centre for Earth Observation Science University of ManitobaWinnipegR3T 2N2Canada

The distribution and fractionation of persistent organic pollutants(POPs)in different matrices refer to how these pollutants are dispersed and separated within various environmental *** is a significant study area as it helps us understand the transport efficiencies and long-range transport potentials of POPs to enter remote areas,particularly polar *** study provides a comprehensive review of the progress in understanding the distribution and fractionation of *** focus on the contributions of four intermedia processes(dry and wet depositions for gaseous and particulate POPs)and determine their transfer between air and *** processes are controlled by their partitioning between gaseous and particulate phases in the *** distribution patterns and fractionations can be categorized into primary and secondary *** are developed to quantificationally study the primary and secondary distributions and fractionations of *** analysis results suggest that the transfer of low molecular weight(LMW)POPs from air to soil is mainly through gas diffusion and particle deposition,whereas high molecular weight(HMW)POPs are mainly via particle ***-POPs tend to be trapped near the source,whereas LMW-POPs are more prone to undergo long-range atmospheric *** crucial distinction elucidates the primary reason behind their temperatureindependent primary ***,the secondary distribution and fractionation can only be observed along a temperature gradient,such as latitudinal or altitudinal *** animation is produced by a one-dimensional transport model to simulate conceptively the transport of CB-28 and CB-180,revealing the similarities and differences between the primary and secondary distributions and *** suggest that the decreasing temperature trend along latitudes is not the major reason for POPs to be fractionated into the polar ecosystems,but drives the longer-term accumu

关键词： POPs Primary and secondary sources Primary and secondary emissions Primary and secondary distribution patterns Primary and secondary fractionations

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Laser-Induced Methanol Decomposition for Ultrafast Hydrogen Production

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Research 2024年第1期2023卷 131-137页

作者： Weiwei Cao Yinwu Li Bo yan Zhiping Zeng pu Liu Zhuofeng Ke Guowei yang State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterSun Yat-sen UniversityGuangzhou 510275P.R.China School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275P.R.China

Methanol(CH_(3)OH)is a liquid hydrogen(H_(2))source that effectively releases H_(2) and is convenient for *** thermocatalytic CH_(3)OH reforming reaction is used to produce H_(2),but this process needs to undergo high reaction temperature(e.g.,200℃)along with a catalyst and a large amount of carbon dioxide(CO_(2))*** photocatalysis and photothermal catalysis under mild conditions are proposed to replace the traditional thermal catalysis to produce H_(2) from CH_(3)OH,they still inevitably produce CO_(2) emissions that are detrimental to carbon ***,we,for the first time,report an ultrafast and highly selective production of H_(2) without any catalysts and no CO_(2) emission from CH_(3)OH by laser bubbling in liquid(LBL)at room temperature and atmospheric pressure.

关键词： catalysis reforming replace

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