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Research 2024年第1期2023卷 247-259页

作者： Hao Xu Junsheng zeng Dongxiao Zhang BIC-ESAT EREand SKLTCSCollege of EngineeringPeking UniversityBeijing 100871P.R.China Institute of Applied Physics and Computational Mathematics Beijing 100088P.R.China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200ZhejiangP.R.China National Center for Applied Mathematics Shenzhen(NCAMS) Southern University of Science and TechnologyShenzhen 518055GuangdongP.R.China Department of Mathematics and Theories Peng Cheng LaboratoryShenzhen 518000GuangdongP.R.China

Data-driven discovery of partial differential equations(PDEs)has recently made tremendous progress,and many canonical PDEs have been discovered successfully for proof of ***,determining the most proper PDE without prior references remains challenging in terms of practical *** this work,a physics-informed information criterion(PIC)is proposed to measure the parsimony and precision of the discovered PDE *** proposed PIC achieves satisfactory robustness to highly noisy and sparse data on 7 canonical PDEs from different physical scenes,which confirms its ability to handle difficult *** PIC is also employed to discover unrevealed macroscale governing equations from microscopic simulation data in an actual physical *** results show that the discovered macroscale PDE is precise and parsimonious and satisfies underlying symmetries,which facilitates understanding and simulation of the physical *** proposition of the PIC enables practical applications of PDE discovery in discovering unrevealed governing equations in broader physical scenes.

关键词： process canonical proof

CFD-DEM study of impacts of the porous distributor medium on fluidization characteristics of a 2D-fluidized bed

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Particuology 2024年第4期87卷 54-73页

作者： Fei Wang Yishan zeng Hao Yan School of Mechanical Engineering Hefei University of TechnologyHefei230009China

Gas-solid bubbling fluidized beds are widely used in chemical,energy,construction,and other industrial fields due to their excellent fluidization performance.2D-fluidized beds with planar rectangular columns of finite thickness are widely used in fluidized bed studies,and it is essential for understanding the hydrodynamics of gas-particle ***,the distributor(porous medium)at the bottom of the bed has a crucial influence on the fluidization performance of the 2D-fluidized *** this work,the fluidization mechanism and gas-solid dynamic characteristics of the fluidized bed under three porous media are studied by CFD-DEM coupled with the porous medium model,and the accuracy of numerical simulation is verified by a high-speed photography *** show that with the increase in the flow resistance of the porous medium,the average and standard deviation of the bubble diameter decrease,and the time and position of particles in the dead zone to participate in the core-annular flow *** a low fluidization velocity,the dead zone in the bed can be considerably reduced by increasing the flow resistance.

关键词： Fluidized bed CFD-DEM Porous medium Bubble dynamics Solid mixing

Achieving strength–ductility synergy in novel paramagnetic Fe-based medium-entropy alloys through deep cryogenic deformation

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Rare Metals 2024年第9期43卷 4493-4507页

作者： Hu-wen Ma Yan-Chun Zhao Li Feng Tian-zeng Liu Zhi-Qi Yu Bo Jin Wang-Chun Duan Peter K.Liaw Dong Ma State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of Technology wenzhou Pump and Valve Engineering Research Institute Lanzhou University of Technology Iron and Steel Research Institute Jiuquan Iron and Steel Corporation Lanzhou Resources and Environment Voc-Tech University Department of Materials Science and Engineering The University of Tennessee Neutron Science Center Songshan Lake Materials Laboratory

Cryogenic pre-deformation treatment has been widely used to effectively improve the comprehensive mechanical properties of steels and novel metals. However,the dislocation evolution and phase transformation induced by different degrees of deep cryogenic deformation are not yet fully elucidated. In this study, the effects of multiple cryogenic pre-treatments on the mechanical properties and deformation mechanisms of a paramagnetic Fe63.3Mn14-Si9.1Cr9.8C3.8medium-entropy alloy（MEA） were investigated, leading to the discovery of a pretreated MEA that exhibits exceptional mechanical properties, including a fracture strength of 3.0 GPa, plastic strain of 26.1% and work-hardening index of 0.57. In addition, X-ray diffraction（XRD） and transmission electron microscopy（TEM）analyses revealed that multiple cryogenic pre-deformation treatments significantly increased the dislocation density of the MEA(from 9 × 1015to 4 × 1016m-2after three pretreatments), along with a transition in the dislocation type from predominantly edge dislocations to mixed dislocations（including screw-and edge-type dislocations）. Notably, this pretreated MEA retained its paramagnetic properties（μr< 1.0200） even after fracture. Thermodynamic calculations showed that cryogenic pretreatment can significantly reduce the stacking fault energy of the MEA by a factor of approximately four(i.e., from 9.7 to2.6 m J·m-2), thereby activating the synergistic effects of transformation-induced plasticity, twinning-induced plasticity and dislocation strengthening mechanisms. These synergistic effects lead to simultaneous strength and ductility enhancement of the MEA.

关键词： Deep cryogenic transformation Dislocation evolution Iron-based medium-entropy alloys Phase transformation Stacking fault energy

Exploring the impact of pericentric inversion of chromosome 9 on fertility in sperm donors

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Asian Journal of Andrology 2024年第3期26卷 302-307页

作者： Qian Liu wen-Jun Zhou zeng-Hui Huang Xiu-Hai Huang Jian Wu Xi-Ren Ji Xue-Feng Luo Yu-Ling Tang Rui-Jun Wang Li-Qing Fan Chuan Huang wen-Bing Zhu Institute of Reproductive and Stem Cell Engineering Basic Medicine CollegeCentral South UniversityChangsha 410013China Clinical Research Center for Reproduction and Genetics in Hunan Province Reproductive and Genetic Hospital of CITIC-XiangyaChangsha 410005China

Pericentric inversion of chromosome 9(inv[9])is a common chromosomal structural variant,but its impact on clinical outcomesremains *** screening criteria of sperm banks are rarely mentioned to individuals with inv(9).In this study,we evaluatedthe fertility of sperm donors with inv(9)who met eligibility criteria for sperm banks(inv[9]-eligible donors).From March 2004 toMay 2022,chromosomal analysis of 16124 sperm donors at CITIC-Xiangya Human Sperm Bank in Hunan Province(Changsha,China)found that 251(1.6%)had chromosome variations,with inv(9)being the most prevalent at 1.1%.All 169 inv(9)-eligibledonors were contacted to collect fertility outcome data,along with 206 eligible donors without inv(9)as *** addition,semen samples from inv(9)-eligible donors and eligible donors underwent assessments of sperm fluorescence in situ hybridization(FISH),mitochondrial membrane potential,DNA fragmentation index,acrosome integrity,reactive oxygen species(ROS),andsperm *** showed that inv(9)did not significantly increase reproductive risks *** detecting ROSlevel differences,the clinical impact may be *** study provides new data on the inv(9)population that can serveas a valuable reference for decision-making by sperm banks as well as for genetic counseling and clinical guidance for individualscarrying inv(9)variant.

关键词： male fertility pericentric inversion of chromosome 9 sperm bank sperm functional parameters

Prescribed Performance Evolution Control for Quadrotor Autonomous Shipboard Landing

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1151-1162页

作者： Yang Yuan Haibin Duan Zhigang zeng State Key Laboratory of Virtual Reality Technology and Systems the School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083China State Key Laboratory of Virtual Reality Technology and Systems the School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083 Virtual Reality Fundamental Research Laboratory Department of Mathematics and TheoriesPeng Cheng LaboratoryShenzhen 518000China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China

The shipboard landing problem for a quadrotor is addressed in this paper,where the ship trajectory tracking control issue is transformed into a stabilization control issue by building a relative position *** guarantee both transient performance and steady-state landing error,a prescribed performance evolution control(PPEC)method is developed for the relative position *** addition,a novel compensation system is proposed to expand the performance boundaries when the input saturation occurs and the error exceeds the predefined *** the wind and wave on the relative position model,an adaptive sliding mode observer(ASMO)is designed for the disturbance with unknown upper *** on the dynamic surface control framework,a shipboard landing controller integrating PPEC and ASMO is established for the quadrotor,and the relative position control error is guaranteed to be uniformly ultimately *** results have verified the feasibility and effectiveness of the proposed shipboard landing control scheme.

关键词： error integrating stabilization

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Basilic vein variation encountered during surgery for arm vein port:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2086-2091页

作者： Cheng-Da Hu Rui Lv Ya-Xin Zhao Ming-Hao Zhang Hong-Dou zeng Yi-wen Mao Department of Breast Surgery The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly *** vein variation usually presents without any clinical symptoms and is often regarded as a benign *** case was a patient with congenital basilic vein variation encountered during surgery for an infusion *** SUMMARY We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port *** peculiarity has hitherto remained undescribed in the *** offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its *** conducted a comprehensive review of analogous cases in the literature,offering pertinent therapeutic recommendations and solutions,with the aim of enhancing the efficacy and safety of future arm port *** Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy,so as not to affect subsequent treatment.

关键词： Totally implantable venous access ports Arm ports Venous variation Postoperative breast cancer Systematic review Case report

The Optical Variability Properties of TeV Blazars

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Research in Astronomy and Astrophysics 2024年第9期24卷 68-77页

作者： Zi-An Su wen-Xin Yang Xiang-Tao zeng Le-Jian Ou Ze-Lin Li Jiang-He Yang Jun-Hui Fan Department of Physics School of Physics and Electronics Hunan Normal University Center for Astrophysics Guangzhou University Greater Bay Brand Center of the National Astronomical Data Center Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province College of Microelectronics Feicuihu Campus of Hefei University of Technology College of Mathematics and Physics Science Hunan University of Arts and Science

Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability,although this kind of association is unclear *** this work,we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale,the brightness-dependent spectral property,the correlation between the the brightness variation and the polarization,and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 20 TeV *** analyses arrive at the following results:（1） The largest variation amplitude in R-band,ΔRM,covers a range fromΔRM=0.29 mag （1ES 2344+514） toΔRM=4.66 mag （3C 279）.（2） Intra-day variability was found from five sources with timescales from 0.14 day for S5 0716+714 to 0.98 day for PKS 2155–*** sources show spectra that are bluer when they become brighter,suggesting a common bluer-when-brighter property.（3） The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization.（4） The largest polarization is correlated with the largest optical variation,suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.

关键词： galaxies: active galaxies: jets radiation mechanisms: non-thermal

Core and variable antimicrobial resistance genes in the gut microbiomes of Chinese and European pigs

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Zoological Research 2024年第1期45卷 189-200页

作者： Cui-Hong Tong Zhi-Peng Huo Lu Diao Dan-Yu Xiao Ruo-Nan Zhao Zhen-Ling zeng wen-Guang Xiong Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation South China Agricultural UniversityGuangzhouGuangdong 510642China National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria College of Veterinary MedicineSouth China Agricultural UniversityGuangzhouGuangdong 510642China National Laboratory of Safety Evaluation(Environmental Assessment)of Veterinary Drugs South China Agricultural UniversityGuangzhouGuangdong 510642China National Reference Laboratory of Veterinary Drug Residues South China Agricultural UniversityGuangzhouGuangdong 510642China

Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial *** its importance,the characterization of ARGs and microbiome structures,as well as the identification of indicators for routine ARG monitoring in pig farms,are still lacking,particularly concerning variations in antimicrobial exposure in different countries or ***,metagenomics and random forest machine learning were used to elucidate the ARG profiles,microbiome structures,and ARG contamination indicators in pig manure under different antimicrobial pressures between China and *** showed that Chinese pigs exposed to high-level antimicrobials exhibited higher total and plasmid-mediated ARG abundances compared to those in European pigs(P<0.05).ANT(6)-Ib,APH(3')-IIIa,and tet(40)were identified as shared core ARGs between the two pig ***,the core ARGs identified in pig populations were correlated with those found in human populations within the same geographical *** and Prevotella were identified as the dominant genera in the core microbiomes of Chinese and European pigs,*** ARG markers and 43 biomarkers were able to differentiate between the Chinese and European pig manure samples with accuracies of 100%and 98.7%,*** for assessing ARG contamination in Chinese and European pigs also achieved high accuracy(r=0.72-0.88).Escherichia flexneri in both Chinese and European pig populations carried between 21 and 37 *** results of this study emphasize the importance of global collaboration in reducing antimicrobial resistance risk and provide validated indicators for evaluating the risk of ARG contamination in pig farms.

关键词： Metagenomic Pig manure Antimicrobial pressure Antimicrobial resistance genes Microbiome

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Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center

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Nano-Micro Letters 2024年第12期16卷 515-531页

作者： wenjing Quan Jia Shi Min zeng wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua Yang Nantao Hu Tao Wang Zhi Yang National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China

Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas ***,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was *** sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 *** analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for ***,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid *** sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing ***,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity *** work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

关键词： Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation

MH-STRALP:A scoring system for prognostication in patients with upper gastrointestinal bleeding

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 790-806页

作者： Jun-Nan Hu Fei Xu Ya-Rong Hao Chun-Yan Sun kai-Ming Wu Yong Lin Lan Zhong Xin zeng Department of Gastroenterology Shanghai East HospitalTongji University School of MedicineShanghai 200120China Department of Gastroenterology Shanghai Changzheng HospitalNavy Military Medical UniversityShanghai 200003China

BACKGROUND Upper gastrointestinal bleeding(UGIB)is a common medical emergency and early assessment of its outcomes is vital for treatment *** To develop a new scoring system to predict its *** In this retrospective study,692 patients with UGIB were enrolled from two cen-ters and divided into a training(n=591)and a validation cohort(n=101).The clinical data were collected to develop new prognostic prediction *** en-dpoint was compound outcome defined as(1)demand for emergency surgery or vascular intervention,(2)being transferred to the intensive care unit,or(3)death during *** models’predictive ability was compared with previously esta-blished scores by receiver operating characteristic(ROC)*** Totally 22.2%(131/591)patients in the training cohort and 22.8%(23/101)in the validation cohort presented poor *** on the stepwise-forward Lo-gistic regression analysis,eight predictors were integrated to determine a new post-endoscopic prognostic scoring system(MH-STRALP);a nomogram was de-termined to present the *** with the previous scores(GBS,Rock-all,ABC,AIMS65,and PNED score),MH-STRALP showed the best prognostic prediction ability with area under the ROC curves(AUROCs)of 0.899 and 0.826 in the training and validation cohorts,*** to the calibration cur-ve,decision curve analysis,and internal cross-validation,the nomogram showed good calibration ability and net clinical benefit in both *** removing the endoscopic indicators,the pre-endoscopic model(pre-MH-STRALP score)was ***,the pre-MHSTRALP score showed better predictive value(AUROCs of 0.868 and 0.767 in the training and validation cohorts,respectively)than the other pre-endoscopic *** The MH-STRALP score and pre-MH-STRALP score are simple,convenient,and accurate tools for prognosis prediction of UGIB,and may be applied for early decision on its management strategies.

关键词： Upper gastrointestinal bleeding Prognosis prediction Retrospective study Nomogram Post-endoscopic model Pre-endoscopic model