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Chinese Medical Journal 2023年第15期136卷 1876-1878页

作者： Ruihan Wang Tong Yuan yuanqing kan Jianing Yue Bin Chen Zhihui Dong Daqiao Guo Yi Si Weiguo Fu Department of Vascular Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Vascular Surgery Institute of Fudan University Shanghai 200032China National Clinical Research Center for Interventional Medicine Shanghai 200032China

To the Editor:Ruptured abdominal aortic aneurysm(rAAA)is a fatal disease.Emergency surgery is the only way to provide an opportunity for survival.In 1994,endovascular aortic repair(EVAR)was reported as an emergency treatment for rAAA.Compared with traditional open surgery(OS),patients could benefit from its lower perioperative mortality and minimal invasiveness.Although recent guidelines have recommended an EVARfirst approach if suitable as judged by the clinician,the standard of whether to give a priority to EVAR varies among clinicians in practical applications,because hostile aortic morphology and hemodynamic conditions were thought to weaken the benefit of EVAR.Hence,controversies still exist regarding whether EVAR as a priority is applicable to most rAAAs.In addition,a search of the literature found few population-based studies with long-term outcomes.Given this,a population-based study was conducted by Zhongshan Hospital,Fudan University.

关键词： aortic aneurysm abdominal

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 dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi surfaces.It is challenging to describe these processes according to a uniform morphology.Therefore,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of gravel.Collecting morphology information for Gobi gravels is essential for studying its genesis and sand saltation.To 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 size.Leveraging multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear quality.Additionally,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point clouds.Advanced 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 gravels.These systematic processes allow precise and detailed characterization of individual gravels.For gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodology for measuring 3D parameters of individual gr

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)

Adipose-derived stem cell/FGF19-loaded microfluidic hydrogel microspheres for synergistic restoration of critical ischemic limb

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Bioactive Materials 2023年第9期27卷 394-408页

作者： Ruihan Wang Fangqian Wang Shan Lu Bin Gao yuanqing kan Tong Yuan Yisheng Xu Chen Yuan Daqiao Guo Weiguo Fu Xiaohua Yu Yi Si Department of Vascular Surgery Zhongshan Hospital Fudan UniversityShanghai200032PR China Institute of Vascular Surgery Fudan UniversityShanghai200032PR China National Clinical Research Center for Interventional Medicine Shanghai200032PR China Department of Orthopedics The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou310009ZhejiangPR China Key Laboratory of Motor System Disease Research and Precision Therapy of Zhejiang Province Hangzhou310000ZhejiangPR China State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237China

The efficacy of stem cell therapy is substantially compromised due to low cell survival rate and poor local retention post-delivery. These issues drastically limit the application of stem cells for ischemic limb therapy, which requires effective blood perfusion and skeletal muscle regeneration. Herein, based on microfluidic technology, an integrated stem cell and cytokine co-delivery system designed for functional ischemic limb salvage was constructed by first incorporating the myogenic cytokine, fibroblast growth factor 19 (FGF19), into microspheres composed of methacrylate gelatin (GelMA). Then adipose-derived stem cells (ADSCs) were highly absorbed into the porous structure of the microspheres, overcoming the insufficient loading efficiency and activities by conventional encapsulation strategy. The fabricated ADSCs/FGF19@μsphere system demonstrated a uniform size of about 180 μm and a highly porous structure with pore sizes between 20 and 40 μm. The resultant system allowed high doses of ADSCs to be precisely engrafted in the lesion and to survive, and achieved sustained FGF19 release in the ischemic region to facilitate myoblast recruitment and differentiation and myofibrils growth. Furthermore, the combination of ADSCs and FGF19 exhibited a positive synergistic effect which substantially improved the therapeutic benefit of angiogenesis and myogenesis, both in vitro and in vivo. In summary, a stem cell and cytokine co-delivery system with the properties of easy preparation and minimal invasiveness was designed to ensure highly efficient cell delivery, sustained cytokine release, and ultimately realizes effective treatment of ischemic limb regeneration.

关键词： Microfluidic technology Stem cell Cytokine Porous microspheres Ischemic limb salvage

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 technology.Aiming 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)R.It outlines the fundamental principles,advantages,and limitations of Si photocathodes with key performance metrics.Based 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.The design ideas of this advantageous three-layer structure in promoting the efficiency,stability,and selectivity have been clarified.Then,this review scrutinizes the influence of the photocathodic chemical environment.This review consolidates the mechanism insights and notable breakthroughs of various fuel generation processes within Si-based PEC-CO_(2)R systems.Providing 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

Role of Oncostatin M in the prognosis of inflammatory bowel disease: A meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 228-238页

作者： Yue Yang kan-Zuo Fu Gu Pan Department of Gastroenterology III Heilongjiang Provincial HospitalHarbin 150036Heilongjiang ProvinceChina Department of Nursing The Second Hospital of HarbinHarbin 150056Heilongjiang ProvinceChina

BACKGROUND Oncostatin M(OSM)is a pleiotropic cytokine which is implicated in the path-ogenesis of inflammatory bowel disease(IBD).AIM To evaluate the prognostic role of OSM in IBD patients.METHODS Literature search was conducted in electronic databases(Google Scholar,Embase,PubMed,Science Direct,Springer,and Wiley).Studies were selected if they reported prognostic information about OSM in IBD patients.Outcome data were synthesized,and meta-analyses were performed to estimate standardized mean differences(SMDs)in OSM levels between treatment responders and non-res-ponders and to seek overall correlations of OSM with other inflammatory bio-markers.RESULTS Sixteen studies(818 Crohn’s disease and 686 ulcerative colitis patients treated with anti-tumor necrosis factor-based therapies)were included.OSM levels were associated with IBD severity.A meta-analysis found significantly higher OSM levels in non-responders than in responders to therapy[SMD 0.80(0.33,1.27);P=0.001],in non-remitters than in remitters[SMD 0.75(95%CI:0.35 to 1.16);P<0.0001]and in patients with no mucosal healing than in those with mucosal heal-ing[SMD 0.63(0.30,0.95);P<0.0001].Area under receiver operator curve values showed considerable variability between studies but in general higher OSM levels were associated with poor prognosis.OSM had significant correlations with Simple Endoscopic Score of Crohn’s disease[r=0.47(95%CI:0.25 to 0.64);P<0.0001],Mayo Endoscopic Score[r=0.35(95%CI:0.28 to 0.41);P<0.0001],fecal calprotectin[r=0.19(95%CI:0.08 to 0.3);P=0.001],C-reactive protein[r=0.25(95%CI:0.11 to 0.39);P<0.0001],and platelet count[r=0.28(95%CI:0.17 to 0.39);P<0.0001].CONCLUSION OSM is a potential candidate for determining the severity of disease and predicting the outcomes of anti-tumor necrosis factor-based therapies in IBD patients.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Oncostatin M Prognosis

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 data.Therefore,several key issues are investigated in the paper.First,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 observations.The 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 observations.However,during both comparisons,significant biases are observed in certain channels.The 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 NOAA-20.Furthermore,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 transmittance.To further explore the difference between the apodized and unapodized simulations,Sinc function is adopted in the fast transmittance model.It is found that the use of Sinc function can make the simulations fit the original satellite observations better.When simulating with apodized observations,the use of Sinc function exhibits larger deviations compared to the Hamming function.Moreover,a correction module is applied to minimize the impact of Non-Local Thermodynamic Equilibrium(NLTE)in the shortwave infrared band.It 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)

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 geometries.In 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 laser.The 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 structure.Cracking 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 content.Finally,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 alloys.The 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

Distribution of phytoplankton community and its influence factors in an urban river network,East China

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Frontiers of Environmental Science & Engineering 2018年第6期12卷 133-144页

作者： Ling Sun Hui Wang yuanqing kan Shiliang Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Tianjin Key Laboratory of Animal and Plant Resistance College of Life SciencesTianjin Normal UniversityTianjin 300387China Tianjin Academy of Environmental Sciences Tianjin 300191China School of Geography and Tourism Qufu Normal UniversityRizhao 276826China

Effects of urban river conditions on phytoplankton community were investigated. Nitrate utilization and hydrodynamic condition affected phytoplankton distribution. A winter bloom was induced by abundant ammonia, tota... 详细信息

关键词： Phytoplankton composition Spatiotemporal distribution Functional groups Nitrate nitrogen Winter bloom

Assessing efficacy of standard impregnation techniques on die-cast aluminum alloys using X-ray micro-CT

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China Foundry 2024年第3期21卷 276-286页

作者： Ajith Bandara Koichi kan Katanaga Yusuke Natsuto Soga Akifumi Koike Toru Aoki Hamamatsu TSC Chuo Hatsumei Institute322 lida-choMinami-kuHamamatsu435-0028Japan Graduate School of Medical Photonics ShizuokaUniversityJohoku 3-5-1HamamatsuShizuoka432-8561Japan ANSeeN Inc Johoku 3-5-1HamamatsuShizuoka432-8561Japan Research Institute of Electronics ShizuokaUniversityJohoku 3-5-1HamamatsuShizuoka432-8561Japan

Utilizing lightweight Al alloys in various industrial applications requires achieving precise pressure tightness and leak requirements.Vacuum pressure impregnation(VPI)with thermosetting polymers is commonly used to address leakage defects in die-cast Al alloys.In this study,the efficacy of the VPI technique in sealing alloy parts was investigated using a combination of nondestructive micro X-ray computed tomography(micro XCT)and a standard leak test.The results demonstrate that the commonly used water leak test is insufficient for determining the sealing performance.Instead,micro XCT shows distinct advantages by enabling more comprehensive analysis.It reveals the presence of a low atomic number impregnates sealant within casting defects,which has low grey contrast and allows for visualizing primary leakage paths in 3D.The effective atomic number of impregnated resin is 6.75 and that of Al alloy is 13.69 by dual-energy X-ray CT.This research findings will contribute to enhancing the standard VPI process parameters and the properties of impregnating sealants to improve quality assurance for impregnation in industrial metals.

关键词： nondestructive testing Al alloy die-casting vacuum pressure impregnation micro X-ray computed tomography duel-energy X-ray CT

Aerodynamic Analysis and Optimization of Pantograph Streamline Fairing for High-Speed Trains

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1075-1091页

作者： Xiang kan Yan Li Tian Li Jiye Zhang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu610031China Technical Center Southwest Jiaotong University Chengdu Design Institute Co.Ltd.Chengdu610031China

A pantograph serves as a vital device for the collection of electricity in trains.However,its aerodynamic resistance can limit the train’s running speed.As installing fairings around the pantograph is known to effectively reduce the resistance,in this study,different fairing lengths are considered and the related aerodynamic performances of pantograph are assessed.In particular,this is accomplished through numerical simulations based on the k-ωShear Stress Transport(SST)two-equation turbulence model.The results indicate that the fairing diminishes the direct impact of high-speed airflow on the pantograph,thereby reducing its aerodynamic resistance.However,it also induces interferences in the flow field around the train,leading to variations in the aerodynamic resistance and lift of train components.It is shown that a maximum reduction of 56.52%in pantograph aerodynamic resistance and a peak decrease of 3.38%in total train aerodynamic resistance can be achieved.

关键词： Pantograph fairing train aerodynamic numerical simulation