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Investigation on the vortical structures by the Liutex method in turbulent channels at Re_(τ)=180 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： Zhang-dan yu Shang Jiang Hai-dong yu bi-yu pang Xin Dong Yi-qian Wang School of Mathematical Sciences Soochow UniversitySuzhou215006China Beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction *** and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various *** this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well *** conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted *** in wall units of W^(+)=20 and height-width ratio ofγ=0.5 are selected for both riblet *** with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag *** obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further *** compare turbulent statistics of the scalloped riblet case with those of the triangular riblet *** mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and Liutex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the *** also compare the pre-multiplied spectra of streamwise velocity and streamwise Liutex component for the three cases to investigate the energy distribution and characteristics of Liutex *** Liutex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be bene

关键词： Liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

A Liutex-based subgrid stress model for large-eddy simulation

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Journal of Hydrodynamics 2022年第6期34卷 1145-1150页

作者： yuan Ding bi-yu pang Bo-wen Yan Yi-qian Wang yu-xuan Chen yue-hong Qian School of Mathematical Science Soochow UniversitySuzhou215006China Department of Computer Science and Technology Tsinghua UniversityBeijing100084China

The concept of vortex is crucial in both understanding and modeling of *** large eddy simulation(LES),the effect of small-scale eddies onto the large scales or the resolved flow field is modeled by subgrid stress *** though the rotating motions of fluids,i.e.,vortices or eddies are central in developing turbulent models,vortex identification methods are seldom used in these *** this study,we develop a new subgrid model based on the Liutex vector,a new quantity introduced to decompose fluid motions into rigid rotation,pure shear and stretching,and thus identify *** new model is then applied in a decaying homogeneous isotropic turbulence(DHIT)and a turbulent channel flow at Reynolds number Reτ=*** is shown that the new model can predict accurate energy spectra compared with experiments in DHIT and give a well-matched velocity profile in turbulent channel flow without changing the form of the *** directions include improvement of the Liutex based model,for example developing anisotropic subgrid models,and its applications in various turbulent flows.

关键词： Liutex large eddy simulation(LES) subgrid model homogeneous isotropic turbulence turbulent channel flow

Enhancement of bending toughness for Fe-based amorphous nanocrystalline alloy with deep cryogenic-cycling treatment

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China Foundry 2025年第1期22卷 99-107页

作者： Yi-ran Zhang Dong Yang Qing-chun Xiang Hong-yu Liu Jing pang Ying-lei Ren Xiao-yu Li Ke-qiang Qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Qingdao yunlu Advanced Material Technology Co. Ltd.Qingdao 266232ShandongChina

The effects of deep cryogenic-cycling treatment(DCT)on the mechanical properties,soft magnetic properties,and atomic scale structure of the Fe_(73.5)Si_(13.5)B_(9)Nb_(3)Cu_(1)amorphous nanocrystalline alloy were *** DCT samples were obtained by subjecting the as-annealed samples to a thermal cycling process between the temperature of the supercooled liquid zone and the temperature of liquid *** flat plate bending testing,hardness measurements,and nanoindentation experiment,it is found that the bending toughness of the DCT samples is improved and the soft magnetic properties are also slightly *** are attributed to the rejuvenation behavior of the DCT samples,which demonstrate a higher enthalpy of ***,DCT is an effective method to enhance the bending toughness of Fe-based amorphous nanocrystalline alloys without degrading the soft magnetic properties.

关键词： deep cryogenic-cycling treatment Fe-based amorphous nanocrystalline alloy bending toughness rejuvenation

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Advances in human umbilical cord mesenchymal stem cells-derived extracellular vesicles and biomaterial assemblies for endometrial injury treatment

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World Journal of Stem Cells 2025年第1期17卷 6-21页

作者： Wan-yu Zhang Han-bi Wang Cheng-Yan Deng Department of Obstetrics and Gynecology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Obstetrics and Gynecology Peking Union Medical College HospitalBeijing 100730China

Endometrial injury caused by repeated uterine procedures,infections,inflammation,or uterine artery dysfunction can deplete endometrial stem/progenitor cells and impair regeneration,thereby diminishing endometrial receptivity and evidently lowering the live birth,clinical pregnancy,and embryo implantation ***,safe and effective clinical treatment methods or gene-targeted therapies are unavailable,especially for severe endometrial *** cord mesenchymal stem cells and their extracellular vesicles are characterized by their simple collection,rapid proliferation,low immunogenicity,and tumorigenicity,along with their involvement in regulating angiogenesis,immune response,cell apoptosis and proliferation,inflammatory response,and fibrosis,Therefore,these cells and vesicles hold broad potential for application in endometrial *** article reviewed recent research on human umbilical cord mesenchymal stem cells as well as their extracellular vesicles in repairing endometrial injury.

关键词： Endometrial injury Umbilical cord mesenchymal stem cells Extracellular vesicles MicroRNA biomaterial assemblies Regenerative repair

Rab1 and Syntaxin 17 regulate hematopoietic homeostasis through β-integrin trafficking in Drosophila

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Journal of Genetics and Genomics 2025年第1期52卷 51-65页

作者： Fangzhou Luo Luwei Sui Ying Sun Zhixian Lai Chengcheng Zhang Gaoqun Zhang bing bi Shichao yu Li Hua Jin College of Life Sciences Northeast Forestry UniversityHarbinHeilongjiang 150040China Department of Developmental Immunology Max Planck Institute of Immunobiology and EpigeneticsFreiburgGermany

Hematopoiesis is crucial for organismal health,and Drosophila serves as an effective genetic model due to conserved regulatory mechanisms with *** larvae,hematopoiesis primarily occurs in the lymph gland,which contains distinct zones,including the cortical zone,intermediate zone,medullary zone,and posterior signaling center(PSC).Rab1 is vital for membrane trafficking and maintaining the localization of cell adhesion molecules,yet its role in hematopoietic homeostasis is not fully *** study investigates the effects of Rab1 dysfunction on β-integrin trafficking within circulating hemocytes and lymph gland ***1 impairment disrupts the endosomal trafficking of β-integrin,leading to its abnormal localization on cell membranes,which promotes lamellocyte differentiation and alters progenitor dynamics in circulating hemocytes and lymph glands,*** also show that the mislocalization of β-integrin is dependent on the adhesion protein *** reduction of β-integrin at cell boundaries in PSC cells leads to fewer PSC cells and lamellocyte ***,Rab1 regulates the trafficking of β-integrin via the Q-SNARE protein Syntaxin 17(Syx17).Our findings indicate that Rab1 and Syx17 regulate distinct trafficking pathways for β-integrin in different hematopoietic compartments and maintain hematopoietic homeostasis of Drosophila.

关键词： Hematopoiesis Lymphgland Rab1 Syntaxin 17 β-integrin Drosophila

A stretchable, ionic conductive, and adhesive patch electrode with ultra-low on-skin impedance for electrophysiological signal recording

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Science China(Information Sciences) 2025年第2期68卷 391-392页

作者： Yang LI yuzhe GU Sheng QIAN yuncong pang Aoxi yu Shuwen ZHENG Wenjie XIA yuan LIAO Baoguang LIU Shujuan LIU Qiang ZHAO College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications (NJUPT) State Key Laboratory of Organic Electronics and Information Displays & Jiangsu Key Laboratory for biosensors Institute of Advanced Materials (IAM)Nanjing University of Posts&Telecommunications (NJUPT)

Flexible electrodes have significant potential in fields such as healthcare and neuroscience, as they enable comprehensive recording and analysis of human electrical signals, providing deeper insights into physiological conditions and the state of internal organs and tissues [1, 2]. However, commercial Ag/AgCl wet electrodes face issues such as dehydration,poor comfort, and insufficient mechanical strength, while other types of electrodes, like dry and semi-dry electrodes,also have their own limitations, including the higher contact impedance.

关键词： Lithium Chloride

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Multiple primary cancers with gastrointestinal malignant tumors as the first manifestation:Three case reports and review of literature

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World Journal of Gastroenterology 2025年第8期31卷 130-139页

作者： Xin-Ran bi Shuang-Yan Zhao yu-Qi Ma Xiao-yu Duan Ting-Ting Hu Lian-Zhu bi Hong-Yi Cai The First Clinical Medical College of Gansu University of Traditional Chinese Medicine Lanzhou 730000Gansu ProvinceChina Department of Radiotherapy Center Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Department of Gastrointestinal Surgery Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Department of Neurology Hospital of Fengnan DistrictTangshan 063300Hebei ProvinceChina

BACKGROUND The incidence of malignant gastrointestinal(GI)tumors is increasing,and advancements in medical care have significantly improved patient survival *** a result,the number of cases involving multiple primary cancers(MPC)has also *** rarity of MPC and the absence of sensitive and specific dia-gnostic markers often lead to missed or incorrect *** is,therefore,of vital importance to improve the vigilance of clinicians and the accurate diagnosis of this *** with GI malignancies face a higher relative risk of deve-loping additional primary malignant tumors compared to those with other systemic *** monitoring and follow-up are crucial,especially for high-risk groups,which include older adults,men,those with addictions to alcohol and tobacco,those with a family history of tumors,and those who have undergone *** SUMMARY In this article,we report three cases of MPC,each involving malignant tumors of the GI tract as the initial primary carcinoma,offering insights that may aid in effectively managing similar *** Patients with GI malignancies face a higher MPC *** screening and follow-up protocols may enhance detection and treatment outcomes.

关键词： Multiple primary cancer Gastrointestinal tract Synchronous Metachronous Case report

Boosting aqueous nickel-zinc battery stability with bimetallic ion-integrated 1D metal-organic nanowires

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Science China Chemistry 2025年

作者： Yihao Chen Jin Liang Yichun Su Guoyin Zhu Hengyue Xu Hongye Ding Guangxun Zhang Dianheng yu Zizhou Shen Yizhou Zhang Wei Huang Huan pang School of Chemistry and Chemical Engineering Yangzhou University Key Laboratory of Flexible Electronics (KLoFE) & Institute of Advanced Materials (IAM) School of Flexible Electronics (Future Technologies) Nanjing Tech University (NanjingTech) Institute of Advanced Materials and Flexible Electronics (IAMFE) School of Chemistry and Materials Science Nanjing University of Information Science & Technology Department of Chemistry Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Limited by low conductivity,designing cathode materials with excellent electron transfer efficiency for high-performance nickel-zinc batteries （NZBs） remains *** this study,a series of bimetallic metal-organic nanowires were fabricated by doping M ions in NiNTA,resulting in NiMNTA (M=Mg2+,Mn2+,Co2+,Zn2+,Ag+),and NixCo6-xNTA （x=1,2,3,4,5）.The proportions and types of metal ions can be modified without altering the initial coordination structure.X-ray absorption fine structure spectroscopy （XAFS） revealed that only M–O bonds,not metal bonds,were present in the *** performance of Ni2Co4NTA as the cathode for aqueous NZBs was significantly improved,achieving the maximum energy density of 279.17Wh kg-1with the high cycle stability （retention rate of 72.0%after 1,000 cycles）.The flexible Ni2Co4NTA//Zn@carbon cloth battery employing gel electrolyte also exhibits the excellent Coulombic efficiency of 96%after 350 *** approach shows considerable potential for designing one-dimensional materials with bimetallic modifications,providing new strategies for developing cathode materials for NZBs with high specific capacity and cycle stability.

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4D毫米波雷达点云与视觉图像自动外参配准方法

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华南理工大学学报(自然科学版) 2025年第1期53卷 74-83页

作者：毕欣翁才恩王瑜胡再刚同济大学汽车学院上海201804 成都汽车产业研究院四川成都610100 成都天软信息技术有限公司四川成都610041

随着自动驾驶技术的快速发展,环境感知系统对多传感器融合的需求日益增加。4维(4D)毫米波雷达因其在复杂天气和光照条件下的稳定性能而成为自动驾驶领域的重要传感器之一。尽管4D毫米波雷达通过增加俯仰角信息和提高点云密度改善了目标... 详细信息

随着自动驾驶技术的快速发展,环境感知系统对多传感器融合的需求日益增加。4维(4D)毫米波雷达因其在复杂天气和光照条件下的稳定性能而成为自动驾驶领域的重要传感器之一。尽管4D毫米波雷达通过增加俯仰角信息和提高点云密度改善了目标检测的精度,但其点云稀疏性和噪声问题限制了其独立应用。因此,4D毫米波雷达与视觉传感器的融合成为提升自动驾驶感知精度的关键。然而,传统的外参配准方法依赖繁琐的手动操作,难以满足高效自动化配准的需求。为解决这一问题,该文提出了一种基于标定板的4D毫米波雷达与视觉图像自动外参配准方法。该方法首先设计了包含ChArUco标记、红色圆环和角反射器的标定板,然后通过圆检测算法和角反射器检测算法自动提取配准点的图像坐标和雷达点云坐标。此外,还提出了一种通过3D Max和Unity仿真的方式实现配准数据采集与验证的方法。最后,通过实验比较直接线性变换(DLT)和外参配准(EC)2种方法的性能,评估配准精度。结果表明,所设计的标定板和自动配准算法能够有效地减少人工操作,并且在配准点个数较多时,EC方法具有更高的配准稳定性和配准精度。

关键词：多传感器配准 4D毫米波雷达视觉自动驾驶外参配准

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