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Comparison of different magnetic resonance imaging sequences for assessment of fistula-in-ano

World Journal of Radiology 2014年第5期6卷 203-209页

作者： michael R Torkzad hkan ahlstrm Urban Karlbom 12 Reris Grange Close Milford SurreyGU8 5FD United Kingdom Section of Radiology Section Department of Radiology Oncology and Radiation Science Uppsala University SE 75185 Uppsala Sweden Department of Surgery Uppsala University Hospital SE 75185 Uppsala Sweden

AIm: To assess agreement between different forms of T2 weighted imaging(T2WI), and post-contrast T1WI in the depiction of fistula tracts, inflammation, and internal openings with that of a reference test. mEThODS: Thirty-nine consecutive prospective cases were enrolled. The following sequences were used for T2WI: 2D turbo-spin-echo(2D T2 TSE); 3D T2 TSE; short tau inversion recovery(STIR); 2D T2 TSE with fat saturation performed in all patients. T1WI were either a 3D T1-weighted prepared gradient echo sequence with fat saturation or a 2D T1 fat saturation [Spectral presaturation with inversion(SPIR)]. Agreement for each sequence for determination of fistula extension, internal openings, and the presence of active inflammation was assessed separately and blindly against a reference test comprised of follow-up, surgery, endoscopic ultrasound, and assessment by an independent experienced radiologist with access to all ***: Fifty-six fistula tracts were found: 2 intersphincteric, 13 trans-sphincteric, and 24 with additional tracts. The best T2 weighted sequence for depiction of fistula tracts was 2D T2 TSE(Cohen's kappa = 1.0), followed by 3D T2 TSE(0.88), T2 with fat saturation(0.54), and STIR(0.19). Internal openings were best seen on 2D T2 TSE(Cohen's kappa = 0.88), followed by 3D T2 TSE(0.70), T2 with fat saturation(0.54), and STIR(0.31). Detection of inflammation showed Cohen's kappa of 0.88 with 2D T2 TSE, 0.62 with 3D T2 TSE, 0.63 with STIR, and 0.54 with T2 with fat saturation. STIR, 3D T2 TSE, and T2 with fat saturation did not make any contributions compared to 2D T2 TSE. Post-contrast 3D T1 weighted prepared gradient echo sequence with fat saturation showed better agreement in the depiction of fistulae(Cohen's kappa = 0.94), finding internal openings(Cohen's kappa = 0.97), and evaluating inflammation(Cohen's kappa = 0.94) compared to post-contrast 2D T1 fat saturation or SPIR where the corresponding figures were 0.71, 0.66, and 0.87, respectively.

关键词： Fistula magnetic resonance imaging Diagnosis

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Analysis of particle dispersion and cavity formation during bulk particle water entry using fully coupled CFD-DEm-VOF approach

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Particuology 2024年第7期90卷 558-580页

作者： Utkan Çalışkan Sanja mišković Norman B.Keevil Institute of mining Engineering University of British Columbia2329 West MallVancouverBC V6T 1Z4Canada

This paper presents the development and validation of a fully coupled computational fluid dynamics—discrete element method—volume of fluid(CFD-DEm-VOF)model to simulate the complex behavior of particle-laden flows with free *** coupling between the fluid and particle phases is established through the implemented continuity,momentum,and alpha transport *** coupled particle forces such as drag,pressure gradient,dense virtual mass,viscous,and interface forces are also integrated,with drag and dense virtual mass forces being dependent on local *** integrated conservative alpha transport equation ensures phase volume conservation during interactions between particles and ***,we have implemented a trilinear interpolation method designed to operate on unstructured hexahedral *** method has been tested for its ability to properly resolve the coupling effects in the numerical simulations,particularly in cases with a relatively low cell-size *** model is validated through three distinct test cases:single particle water entry,dam break with particles,and water entry of a group of particles *** experimental setup is built to study the dynamics of the water entry of a group of particles,where three key flow features are analyzed:the evolution of average particle velocity,cavity shape,and particle dispersion cloud profiles in *** tests involve four different scenarios,including two different water levels(16.1 and 20.1 cm)and two different particle densities(2650 and 4000 kg/m3).high-speed videometry and particle tracking velocimetry(using ImageJ/Trackmate)methods are employed for experimental data *** is demonstrated that numerical results are in excellent agreement with theoretical predictions and experimental *** study highlights the significance of vortices in cavity shaping and particle *** validated CFD-DEm-VOF model constitutes a robust tool for simulating particle-laden flows,cont

关键词： CFD-DEm-VOF Trilinear interpolation Particle-laden flow Free-surface Particle water entry Volume conservation

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Three-dimensional(3D)parametric measurements of individual gravels in the Gobi region using point cloud technique

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Journal of Arid Land 2024年第4期16卷 500-517页

作者： JING Xiangyu hUANG Weiyi kan Jiangming College of Engineering Beijing Forestry UniversityBeijing 100083China Key Laboratory of State Forestry Administration on Forestry Equipment and Automation Beijing 100083China

Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed *** presence significantly influences the movement of sand and ***,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi *** is challenging to describe these processes according to a uniform ***,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of *** morphology information for Gobi gravels is essential for studying its genesis and sand *** enhance the efficiency and information yield of gravel parameter measurements,this study conducted field experiments in the Gobi region across Dunhuang City,Guazhou County,and Yumen City(administrated by Jiuquan City),Gansu Province,China in march 2023.A research framework and methodology for measuring 3D parameters of gravel using point cloud were developed,alongside improved calculation formulas for 3D parameters including gravel grain size,volume,flatness,roundness,sphericity,and equivalent grain *** multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear ***,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point *** point cloud algorithms,including the Oriented Bounding Box(OBB),point cloud slicing method,and point cloud triangulation,were then deployed to calculate the 3D parameters of individual *** systematic processes allow precise and detailed characterization of individual *** gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodol

关键词： Gobi gravels three-dimensional(3D)parameters point cloud 3D reconstruction Random Sample Consensus(RANSAC)algorithm Density-Based Spatial Clustering of Applications with Noise(DBSCAN)

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Prevalence and Influencing Factor Analysis of Typhoid/Paratyphoid Fever—China,2011-2020

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China CDC weekly 2024年第21期6卷 493-498页

作者： Shumei huang meiying Yan Biao kan School of Public health Shandong UniversityJinan CityShandong ProvinceChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina

Introduction:Over the last 12 years,there has been a consistent decline in the cases of typhoid/paratyphoid fever in *** the epidemiological patterns of these diseases in various provincial-level administrative divisions(PLADs)and examining potential influencing factors can provide crucial information for implementing successful control ***:In this study,we analyzed the cases and incidence rates of typhoid/paratyphoid fever reported in various PLADs of China from 2011 to 2022,along with exploring potential influencing *** initially studied spatial shifts in the incidence rates through centroid shift *** variations in typhoid/paratyphoid fever onset were examined using *** autocorrelation analysis was utilized to understand the spatial correlations among different *** assess potential factors,we utilized a generalized estimating equations model that integrated spatial lag effects and sequence comparison ***:The study identified significant geographical clustering of typhoid/paratyphoid fever cases in southwestern China.A decrease in incidence rates in the west resulted in a movement of the disease center towards the *** incidence occurred during warmer seasons,highlighting the seasonal pattern of the *** such as meteorological conditions and socioeconomic status were probable influencers of typhoid/paratyphoid ***:The geographical and temporal spread of typhoid/paratyphoid fever can be impacted by meteorological and socioeconomic *** economic conditions,particularly in regions with high disease prevalence,could aid in the prevention and management of these fevers.

关键词： prevention utilized meteorological

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Developing silicon-based photocathodes for CO_(2) conversion

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Science China Chemistry 2024年第6期67卷 1904-1921页

作者： Weijie Zhuang miao kan Tao meng Jinlong Zhang Key Laboratory for Advanced materials and Joint International Research Laboratory of Precision Chemistry and molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China Shanghai Engineering Research Center for multimedia Environmental Catalysis and Resource Utilization East China University of Science and TechnologyShanghai200237China

Photoelectrochemical(PEC)conversion of CO_(2) presents a promising avenue for solar-driven chemical fuel production,with silicon emerging as a cost-effective and high-light-absorbing material pivotal to this *** at exploring opportunities for industrializing PEC CO_(2) reduction(PEC-CO_(2)R)by minimizing reaction energy consumption,enhancing reaction efficiency and selectivity,this review summarizes recent advancements in developing Si-based photocathodes for PEC-CO_(2)*** outlines the fundamental principles,advantages,and limitations of Si photocathodes with key performance *** on this understanding,the strategies to enhance the performance of the PEC-CO_(2)R system,including light absorption,charge separation,and catalytic reactions are categorized as the interfacial modification,active site decoration,and protective layer *** design ideas of this advantageous three-layer structure in promoting the efficiency,stability,and selectivity have been ***,this review scrutinizes the influence of the photocathodic chemical *** review consolidates the mechanism insights and notable breakthroughs of various fuel generation processes within Si-based PEC-CO_(2)R *** this wealth of information offers an up-to-date perspective on the dynamic developments in silicon-based PEC-CO_(2) conversion and underscores the promising pathways toward the sustainable fuel synthesis from pollutant CO_(2).

关键词： photoelectrochemistry solar fuels silicon photocathodes carbon dioxide reduction microenvironment

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Temperature-controlled DCP Fluorescent Probe Based on hydrogel-immobilized Quantum Dots Composite

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Journal of Wuhan University of Technology(materials Science) 2024年第4期39卷 931-936页

作者：童伊琳杨坤 hAN Xuecai YU kan BAO Jiaqi Faculty Information Science and Technology Wenhua CollegeWuhan 430074China State Key Laboratory of Silicate materials for Architectures Wuhan University of TechnologyWuhan 430074China Yangtze Optical Fibre and Cable Joint Stock Limited Company Wuhan 430074China

A composite was created by incorporating the quantum dot-enhanced SiO_(2)nanoparticles within this *** on this composite,a temperature-controlled fluorescent probe for DCP was developed.A meticulous examination of this probe revealed its attributes and factors affecting its *** using temperature modulation,the probe was adept at detecting DCP concentrations ranging between 1.0×10^(-6)and 9.0×10^(-6)mol/*** a probe offers remarkable selectivity,repeatability,and robust stability,so that the detection of DCP can be carried out at different temperatures,and a fast,reliable,sensitive and low-cost intelligent detection method is realized.

关键词： temperature-controlled fluorescent probe hydrogel-immobilized quantum dots composite DCP

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Impact of Atmospheric Transmittance and NLTE Correction on Simulation of high Spectral Infrared Atmospheric Sounder onboard FY-3E

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Journal of meteorological Research 2024年第2期38卷 225-234页

作者： Chenggege FANG Peiming DONG Yang hAN Wanlin kan Collaborative Innovation Center on Forecast and Evaluation of meteorological Disasters Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science&TechnologyNanjing 210044 Donghai Laboratory Zhoushan 316021 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 CmA Earth System modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081 Key Laboratory of Transportation meteorology of China meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210041

With the launch of the first civilian early-morning orbit satellite Fengyun-3E(FY-3E),higher demands are placed on the accuracy of radiative transfer simulations for hyperspectral infrared ***,several key issues are investigated in the ***,the accuracy of the fast atmospheric transmittance model implemented in the Advanced Research and modeling System(ARmS)has been evaluated with both the line-by-line radiative transfer model(LBLRTm)and the actual satellite *** results indicate that the biases are generally less than 0.25 K when compared to the LBLRTm,while below 1.0 K for the majority of the channels when compared to the ***,during both comparisons,significant biases are observed in certain *** accuracy of hyperspectral Infrared Atmospheric Sounder-II(hIRAS-II)onboard FY-3E is comparable to,and even superior to that of the Cross-track Infrared Sounder(CrIS)onboard ***,apodization is a crucial step in the processing of hyperspectral data in that the apodization function is utilized as the instrument channel spectral response function to produce the satellite channel-averaged *** further explore the difference between the apodized and unapodized simulations,Sinc function is adopted in the fast transmittance *** is found that the use of Sinc function can make the simulations fit the original satellite observations *** simulating with apodized observations,the use of Sinc function exhibits larger deviations compared to the hamming ***,a correction module is applied to minimize the impact of Non-Local Thermodynamic Equilibrium(NLTE)in the shortwave infrared *** is verified that the implementation of the NLTE correction model leads to a significant reduction in the bias between the simulation and observation for this band.

关键词： high spectral infrared sounding atmospheric transmittance apodization Non-Local Thermodynamic Equilibrium Fengyun-3E(FY-3E)

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microstructure and Internal Friction Behavior of Laser 3D Printed Fe-Based Amorphous Composites

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Acta metallurgica Sinica(English Letters) 2024年第1期37卷 196-204页

作者： Shuilong huang Qingjun Chen Li Ji kan Wang Guosheng huang School of material Science and Engineering Nanchang Hangkong UniversityNanchang330063China State Key Laboratory for marine Corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)Qingdao266237China

Laser 3D printing,also known as laser additive manufacturing(LAm),is favored for its ability to form bulk metallic glass(BmG)and its composite materials(BmGcs)with freeform *** this work,two different kinds of Fe_(41)Co_(7)Cr_(15)mo_(14)C_(15)B_(6)Y_(2)amorphous coatings(A and B)were prepared by using LAm technology under air-and water-cooled conditions,respectively;meanwhile,to reduce the cracks generated due to the residual thermal stresses,coating C obtained by air-sweep annealing of B with a low energy-density *** morphology and amorphous content and microstructure of the coatings were investigated,the results show many cracks in coating B deposited under water-cooled conditions,and its microstructure shows an amorphous-crystal-nanocrystalline mixed *** was suppressed in coating C,obtained by air-sweep annealing based on coating B,but the amorphous content was reduced from 32.6 to 13.4%.And the hardness and corrosion resistance of the coating will increase with the increase in the amorphous ***,the internal friction behavior of a BmGcs was prepared on the basis of the process of sample C is compared with that of as-cast amorphous *** results show that the low temperature internal friction behavior of BmGcs is affected by the defects produced during printing,and the high temperature internal friction behavior is affected by the precipitated hard phase.

关键词： Laser 3D printing Amorphous coating microstructure Corrosion resistance Internal friction behavior

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Boosting bulk charge transport of CuWO_(4) photoanodes via Cs doping for solar water oxidation

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Chinese Journal of Structural Chemistry 2024年第2期43卷 31-37页

作者： Xinyi Fan Xiaojia Yuan kan Zhang School of materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Copper tungstate(CuWO_(4))is a promising photoanode for photoelectrochemical(PEC)water splitting due to its appropriate energy band position and broad light absorption ***,the inherent unfilled 3d atomic orbital of Cu acts as a natural electron-hole recombination site,significantly constraining the PEC performance of CuWO_(4).herein,Cs atoms with complete atomic orbitals are doped into CuWO_(4)in order to obtain better bulk charge separation *** a result,the photocurrent of Cs@CuWO_(4)increases from 0.57 to 0.99 mA cm^(-2)compared to CuWO_(4)at 1.23 V *** hydrogen electrode(RhE)under Am 1.5G illumination,as well as the bulk charge transfer efficiencies rising from 13.5%to 19.3%.In addition,density of states(DOS)calculations further prove that the introduction of Cs atoms effectively suppresses the contribution of Cu 3d orbitals at the Fermi *** work offers a valuable reference for the advancement of CuWO_(4)as the next-generation PEC photoanode material.

关键词： Photoanode Water splitting Photoelectrochemical Charge separation

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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

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