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Intestinal epithelial chemokine (C-C motif) ligand 7 overexpression protects against high fat diet-induced obesity and hepatic steatosis in mice

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Chinese Medical Journal 2020年第15期133卷 1805-1814页

作者： Zhi-Hong Luo meng-wei niu Shen-Hai Gong Guang-Yan Wu Teng Wang Fang-Zhao Wang Guo-Quan wei Zhan-Ke He Yong Jiang Peng Chen Department of Pathophysiology Guangdong Provincial Key Laboratory of ProteomicsSchool of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515 China

Background:We previously found that the intestinal epithelial chemokine(C-C motif)ligand 7(CCL7)plays an important role in the development of toxin-induced acute liver *** detailed effects of intestinal epithelial CCL7 on chronic diseases;however,are still ***,we aimed to investigate the impact of intestinal epithelial CCL7 overexpression on high-fat diet(HFD)-induced obesity and steatohepatitis in ***:Intestinal epithelial CCL7 overexpression(CCL7tgIEC)mice and their wild-type(WT)littermates were fed with normal chow or HFD for 16 weeks to induce obesity and non-alcoholic fatty liver *** weight gain,as well as adipose tissue index were *** injury was monitored by histological analysis and real time polymerase chain *** microbial composition was analyzed by 16S rRNA gene ***:We found that the CCL7tgIEC mice on a HFD had markedly decreased weight gain(8.9 vs.17.0 g,P<0.05)and a lower adipose tissue index that include mesenteric fat(1.0%vs.1.76%,P<0.05),gonadal fat(2.1%vs.6.1%,P<0.05),subcutaneous fat(1.0%vs.2.8%,P<0.05)compared to WT ***-induced glucose intolerance and insulin resistance were also significantly improved in CCL7tgIEC mice compared to ***,HFD-fed CCL7tgIEC mice displayed less hepatic lipid accumulation and lower expression of inflammatory factors than WT mice.16S rRNA gene sequencing demonstrated that CCL7 overexpression in intestinal epithelial cells improved HFD-induced gut microbial ***:Our study revealed that CCL7 overexpression in the intestinal epithelium protects mice against the progression of diet-induced obesity,hepatic steatosis,and enteric dysbiosis.

关键词： Chemokine(C-C motif)ligand 7 Gut microbiota High-fat diet Obesity Steatohepatitis

UKF‐MOT:An unscented Kalman filter‐based 3D multi‐object tracker

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 1031-1041页

作者： meng Liu Jianwei niu Yu Liu Collective Intelligence&Collaboration Laboratory China North Artificial Intelligence and Innovation Research InstituteBeijingChina China North Vehicle Research Institute BeijingChina State Key Laboratory of Software Development Environment School of Computer Science and EngineeringBeihang UniversityBeijingChina State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijingChina School of Computer Science and Engineering Beihang UniversityBeijingChina

Multi‐object tracking in autonomous driving is a non‐linear *** better address the tracking problem,this paper leveraged an unscented Kalman filter to predict the object's *** the association stage,the Mahalanobis distance was employed as an affinity metric,and a Non‐minimum Suppression method was designed for *** the detections fed into the tracker and continuous‘predicting‐matching’steps,the states of each object at different time steps were described as their own continuous *** conducted extensive experiments to evaluate tracking accuracy on three challenging datasets(KITTI,nuScenes and Waymo).The experimental results demon-strated that our method effectively achieved multi‐object tracking with satisfactory ac-curacy and real‐time efficiency.

关键词： autonomous vehicle transportation

A Dual Domain Robust Reversible Watermarking Algorithm for Frame Grouping Videos Using Scene Smoothness

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Computers, Materials & Continua 2024年第6期79卷 5143-5174页

作者： Yucheng Liang Ke niu Yingnan Zhang Yifei meng College of Cryptographic Engineering Engineering University of the Chinese People’s Armed Police ForceXi’an710086China Key Laboratory of Information Security of the Chinese People’s Armed Police Force Engineering University of the Chinese People’s Armed Police ForceXi’an710086China

The proposed robust reversible watermarking algorithm addresses the compatibility challenges between robustness and reversibility in existing video watermarking techniques by leveraging scene smoothness for frame grouping *** in the H.264 video coding standard,the algorithm first employs traditional robust watermark stitching technology to embed watermark information in the low-frequency coefficient domain of the U ***,it utilizes histogram migration techniques in the high-frequency coefficient domain of the U channel to embed auxiliary information,enabling successful watermark extraction and lossless recovery of the original video *** results demonstrate the algorithm’s strong imperceptibility,with each embedded frame in the experimental videos achieving a mean peak signal-to-noise ratio of 49.3830 dB and a mean structural similarity of *** with the three comparison algorithms,the performance of the two experimental indexes is improved by 7.59%and 0.4%on *** the same time,the proposed algorithm has strong robustness to both offline and online attacks:In the face of offline attacks,the average normalized correlation coefficient between the extracted watermark and the original watermark is 0.9989,and the average bit error rate is *** the face of online attacks,the normalized correlation coefficient between the extracted watermark and the original watermark is 0.8840,and the mean bit error rate is *** with the three comparison algorithms,the performance of the two experimental indexes is improved by 1.27%and 18.16%on average,highlighting the algorithm’s ***,the algorithm exhibits low computational complexity,with the mean encoding and the mean decoding time differentials during experimental video processing being 3.934 and 2.273 s,respectively,underscoring its practical utility.

关键词： Robust reversible watermarking scene smoothness dual-domain U channel H.264 encoding standard

Numerical and experimental research on axial injection end-burning hybrid rocket motors with polyethylene fuel

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Chinese Journal of Aeronautics 2024年第8期37卷 91-105页

作者： Xiangyu meng Hui TIAN Lingfei HE Jingfei GAO Xiaoting niu Guobiao CAI School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of EducationBeijing 100816China

This study investigates the end-burning hybrid rocket motors with polyethylene fuel by the numerical simulation and *** on computational fluid dynamics,a numerical model is *** model is validated by two firing tests in this hybrid rocket motor,which uses oxygen and polyethylene as *** results show that the numerical and experimental data are in good agreement,and the error of the chamber pressure is less than 2.63%.Based on the simulation mode,the blowoff limit of the end-burning hybrid rocket motors is *** the nozzle throat diameter and the inner diameter of grain are large,it is more difficult for the hybrid rocket motor to achieve end-burning mode,i.e.,the flame spreading is prevented in the narrow *** main reason is that when the nozzle throat and the grain port are large,chamber pressure and oxidizer flow velocity are ***,the friction velocity considering the pressure and flow velocity is *** critical friction velocity is about 4.054–4.890 m/s in the hybrid rocket *** the friction velocity exceeds the critical friction velocity,the combustion mode in hybrid rocket motors changes from the flame spreading mode to the end-burning ***,the regression rate formula is obtained by fitting,which shows that the regression rate has a good correlation with combustion chamber *** critical friction velocity and regression rate formula can provide an important reference for end-burning hybrid rocket motors.

关键词： Hybrid rocket motor End burning Blowoff limit Flame propagation Regression rate

Optimizing circumferential assembly angle of rotor parts connected by curvic couplings based on acquired tooth surface error data

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Chinese Journal of Aeronautics 2024年第3期37卷 404-416页

作者： Huibin SUN meng LIU Yingzhi ZHANG Chenle wei Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China AECC South Industry Company Limited Zhuzhou 412002China

Due to the excellent self-centering and load-carrying capability,curvic couplings have been widely used in advanced aero-engine ***,curvic tooth surface errors lead to poor assembly *** physical-master-gauge-based indirect tooth surface error measurement and circumferential assembly angle optimization methods have the disadvantages of high cost and weak *** unknown tooth surface fitting mechanism is a big barrier to assembly precision prediction and ***,this work puts forward a data-driven assembly simulation and optimization approach for aero-engine rotors connected by curvic *** origin of curvic tooth surface error is deeply *** 5-axis sweep scan method,a large amount of high-precision curvic tooth surface data are acquired *** on geometric models of parts,the fitting mechanism of curvic couplings is uncovered for assembly precision simulation and prediction.A circumferential assembly angle optimization model is developed to decrease axial and radial assembly *** results show that the assembly precision can be predicted accurately and improved *** uncovering the essential principle of the assembly precision formation and proposing circumferential assembly angle optimization model,this work is meaningful for assembly quality,efficiency and economy improvement of multistage aero-engine rotors connected by curvic couplings.

关键词： Curvic couplings Tooth surface error Assembly precision Axial and radial runouts Circumferential assembly angle

Charge-asymmetry Fe_(1)Cu single-atom alloy catalyst for efficient oxygen reduction reaction

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Nano Research 2024年第6期17卷 4702-4710页

作者： Xudong niu Jian wei Dongyao Xu Jiajing Pei Rui Sui School of Chemical&Environmental Engineering China University of Mining and TechnologyBeijing 100083China Institute of Water Ecology and Environment Chinese Research Academy of Environmental SciencesBeijing 100083China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China

The development of high-efficient and low-cost oxygen reduction reaction(ORR)electrocatalysts is crucial for the practical applications of metal-air *** promising way is to develop Fe single-atom ***,the single active center and inherent electronic structure of Fe single-atom catalysts lead to the undesirable adsorption of multiple ORR ***,a charge-asymmetry single-atom alloy(SAA)catalyst with Fe-Cu dual sites supported on nitrogen-doped carbon nanosheet(Fe_(1)Cu SAA/NC)was *** characterizations manifest the existence of electron interaction between Fe and Cu in Fe_(1)Cu SAA/NC,which facilitates the adsorption of ORR intermediate for fast ***,the charge-asymmetry Fe_(1)Cu SAA/NC exhibits much faster ORR kinetics with a half-wave potential of 0.917 V *** hydrogen electrode(RHE),outperforming its counterparts in the ***,Fe_(1)Cu SAA/NC still maintains a high half-wave potential with only a drop of 5 mV after 5000 cycles,indicating excellent *** work provides a new strategy to design highly active and non-noble metal ORR electrocatalysts,which hold great potential for various catalytic applications.

关键词： Fe_(1)Cu single-atom alloy(SAA) electrocatalysis oxygen reduction reaction charge-asymmetry

On traceable iterated line graph and hamiltonian path index

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 239-252页

作者： niu Zhao-hong XIONG Li-ming YANG wei-hua School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Mathematics and Statistics Beijing Key Laboratory on MCAACIBeijing Institute of TechnologyBeijing 100081China Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥*** this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characterization of G for which L^(n)(G)has a hamiltonian *** applications,we use this characterization to give several upper bounds on the hamiltonian path index of a graph.

关键词： iterated line graph traceable hamiltonian index hamiltonian path index

(g,e)-Symmetric Rings

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Algebra Colloquium 2024年第2期31卷 263-270页

作者： Fanyun meng Junchao wei Nanqing Ding School of Mathematics Yangzhou UniversityYangzhouJiangsu 225002China 不详

Let R be a ring and e,g in E(R),the set of idempotents of *** R is called(g,e)-symmetric if abc=0 implies gacbe=0 for any a,b,c∈***,R is an e-symmetric ring if and only if R is a(1,e)-symmetric ring;in particular,R is a symmetric ring if and only if R is a(1,1)-symmetric *** show that e∈E(R)is left semicentral if and only if R is a(1−e,e)-symmetric ring;in particular,R is an Abel ring if and only if R is a(1−e,e)-symmetric ring for each e∈E(R).We also show that R is(g,e)-symmetric if and only if ge∈E(R),geRge is symmetric,and gxye=gxeye=gxgye for any x,y∈*** e-symmetric rings,we construct some new classes of rings.

关键词： idempotent (g,e)-symmetric ring Abel ring left semicentral

A Study on Enhancing Chip Detection Efficiency Using the Lightweight Van-YOLOv8 Network

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Computers, Materials & Continua 2024年第4期79卷 531-547页

作者： meng Huang Honglei wei Xianyi Zhai School of Mechanical Engineering and Automation Dalian Polytechnic UniversityDalian116034China

In pursuit of cost-effective manufacturing,enterprises are increasingly adopting the practice of utilizing recycled semiconductor *** ensure consistent chip orientation during packaging,a circular marker on the front side is employed for pin alignment following successful functional ***,recycled chips often exhibit substantial surface wear,and the identification of the relatively small marker proves ***,the complexity of generic target detection algorithms hampers seamless *** these issues,this paper introduces a lightweight YOLOv8s-based network tailored for detecting markings on recycled chips,termed ***,to alleviate the influence of diminutive,low-resolution markings on the precision of deep learning models,we utilize an upscaling approach for enhanced *** technique relies on the Super-Resolution Generative Adversarial Network with Extended Training(SRGANext)network,facilitating the reconstruction of high-fidelity images that align with input ***,we replace the original YOLOv8smodel’s backbone feature extraction network with the lightweight VanillaNetwork(VanillaNet),simplifying the branch structure to reduce network ***,a Hybrid Attention Mechanism(HAM)is implemented to capture essential details from input images,improving feature representation while concurrently expediting model inference *** results demonstrate that the Van-YOLOv8 network outperforms the original YOLOv8s on a recycled chip dataset in various ***,it demonstrates superiority in parameter count,computational intricacy,precision in identifying targets,and speed when compared to certain prevalent algorithms in the current *** proposed approach proves promising for real-time detection of recycled chips in practical factory settings.

关键词： Lightweight neural networks attention mechanisms image super-resolution enhancement feature extraction small object detection