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Computers, Materials & Continua 2024年第4期79卷 761-777页

作者： siyuan liu Jinying Huang Jiancheng Ma Licheng Jing Yuxuan Wang School of Data Science and Technology North University of ChinaTaiyuan030051China School of Mechanical Engineering North University of ChinaTaiyuan030051China

Recent research in cross-domain intelligence fault diagnosis of machinery still has some problems,such as relatively ideal speed conditions and sample *** engineering practice,the rotational speed of the machine is often transient and time-varying,which makes the sample annotation increasingly ***,the number of samples collected from different health states is often *** deal with the above challenges,a complementary-label(CL)adversarial domain adaptation fault diagnosis network(CLADAN)is proposed under time-varying rotational speed and weakly-supervised *** the weakly supervised learning condition,machine prior information is used for sample annotation via cost-friendly complementary label learning.A diagnosticmodel learning strategywith discretized category probabilities is designed to avoidmulti-peak distribution of prediction *** adversarial training process,we developed virtual adversarial regularization(VAR)strategy,which further enhances the robustness of the model by adding adversarial perturbations in the target *** experiments on two case studies validated the superior performance of the proposed method.

关键词： Time-varying rotational speed weakly-supervised fault diagnosis domain adaptation

Chemical simulation teaching system based on virtual reality and gesture interaction

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 148-168页

作者： Dengzhen LU Hengyi LI Boyu QIU siyuan liu Shuhan QI School of Computer Science and Technology Harbin Institute of TechnologyShenzhen 518055China Pengcheng Laboratory Shenzhen 518052China

Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage *** address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture *** The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics *** establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was *** code script logic,particle systems,as well as other systems,chemical phenomena were ***,we created an online teaching platform using streaming media and databases to address the problems of distance *** The proposed system was evaluated against two mainstream products in the *** the experiments,the proposed system outperformed the other products in terms of fidelity and *** The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.

关键词： Chemical experiment simulation Gesture interaction Virtual reality Model establishment Process control Streaming media Database

Switchable shape memory polymer bio-inspired adhesive and its application for unmanned aerial vehicle landing

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Chinese Journal of Aeronautics 2024年第3期37卷 380-390页

作者： Qingsong HE Zefang ZHAO Qiyun ZHONG siyuan liu Kai DENG Yongqi liu Ning ZHANG Zijie ZHAO Fengjiang ZHAN Jianfeng ZHAO Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-Sized UAV Ministry of Industry and Information TechnologyUnmanned Aerial Vehicles Research InstituteNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Functional Morphology and Biomechanics Institute of ZoologyKiel UniversityKiel 24098Germany

Controlled and switchable adhesion is commonly observed in biological *** recent years,many scholars have focused on making switchable bio-inspired ***,making a bio-inspired adhesive with high adhesion performance and excellent dynamic switching properties is still a challenge.A Shape Memory Polymer Bio-inspired Adhesive(SMPBA)was successfully developed,well realizing high adhesion(about 337 kPa),relatively low preload(about90 kPa),high adhesion-to-preload ratio(about 3.74),high switching ratio(about 6.74),and easy detachment,which are attributed to the controlled modulus and contact area by regulating temperature and the Shape Memory Effect(SME).Furthermore,SMPBA exhibits adhesion strength of80–337 kPa on various surfaces(silicon,iron,and aluminum)with different roughness(Ra=0.021–10.280)because of the conformal contact,reflecting outstanding surface *** finite element analysis verifies the bending ability under different temperatures,while the adhesion model analyzes the influence of preload on contact area and ***,an Unmanned Aerial Vehicle(UAV)landing device with SMPBA was designed and manufactured to achieve UAV landing on and detaching from various *** study provides a novel switchable bio-inspired adhesive and UAV landing method.

关键词： Bio-inspired adhesive Shape memory polymers Switchable adhesive Unmanned aerial vehicle Landing

BMP9 induces osteogenic differentiation through up-regulating LGR4 via the mTORC1/ Stat3 pathway in mesenchymal stem cells

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Genes & Diseases 2024年第3期11卷 468-483页

作者： Jie Zhang Jinhai Jiang Hang liu Shiyu Wang Kaixin Ke siyuan liu Yue Jiang Lu liu Xiang Gao Baicheng He Yuxi Su Department of Pharmacology School of PharmacyChongqing Medical UniversityChongqing 400016China Key Laboratory of Biochemistry and Molecular Pharmacology of Chongqing Chongqing Medical UniversityChongqing 400016China Department of Orthopedics Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China orthopedics Department Children's Hospital of Chongqing Medical UniversityChongqing 400014China China International Science and Technology Cooperation Base of Child Development and Critical Disorders Jiangxi Hospital Affiliated Children's Hospital of Chongqing Medical UniversityJiangxi 330000China National Clinical Research Center for Child Health and Disorders China

Bone defects and non-union are prevalent in clinical orthopedy,and the outcomes of current treatments are often *** tissue engineering offers a promising approach to treating these conditions *** morphogenetic protein 9(BMP9)can commit mesenchymal stem cells to osteogenic lineage,and a knowledge of the underlying mechanisms may help advance the field of bone tissue ***-rich repeats con-taining G protein-coupled receptor 4(LGR4),a member of G protein-coupled receptors,is essential for modulating bone *** study is aimed at investigating the impact of LGR4 on BMP9-induced osteogenesis in mesenchymal stem cells as well as the underlying *** marrow stromal cells from BMp9-knockout mice exhibited diminished LGR4 expression,and exogenous LGR4 clearly restored the impaired osteogenic potency of the bone marrow stromal ***,LGR4 expression was increased by BMP9 in C3H10T1/2 ***4 augmented the benefits of BMP9-induced osteogenic markers and bone formation,whereas LGR4 inhibition restricted these ***,the BMP9-induced li-pogenic markers were increased by LGR4 *** protein levels of Raptor and p-Stat3 were elevated by *** knockdown or p-Stat3 suppression attenuated the osteoblastic markers and LGR4 expression brought on by ***4 significantly reversed the blocking ef-fect of Raptor knockdown or p-Stat3 suppression on the BMP9-induced osteoblastic *** interacts with p-Stat3,and p-Stat3 activates the LGR4 promoter *** conclusion,LGR4 boosts BMP9 osteoblastic potency in mesenchymal stem cells,and BMP9 may up-regulate LGR4 via the mTORC1/Stat3 signal activation.

关键词： BMP9 LGR4 mTORC1 Osteogenic differentiation Stat3

Rumen metagenome reveals the mechanism of mitigation methane emissions by unsaturated fatty acid while maintaining the performance of dairy cows

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ANIMAL NUTRITION 2024年第3期18卷 296-308页

作者： Yang, Zhantao Zheng, Yuhui liu, siyuan Xie, Tian Wang, Qianqian Wang, Zhonghan Li, Shengli Wang, Wei China Agr Univ Coll Anim Sci & Technol Beijing Engn Technol Res Ctr Raw Milk Qual & Safet State Key Lab Anim Nutr & Feeding Beijing 100193 Peoples R China

Dietary fat content can reduce the methane production of dairy cows; however, the relevance fatty acid (FA) composition has towards this inhibitory effect is debatable. Furthermore, in-depth studies elucidating the effects of unsaturated fatty acids (UFA) on rumen function and the mechanism of reducing methane (CH4) production are lacking. This study exposed 10 Holstein cows with the same parity, similar milk yield to two total mixed rations: low unsaturated FA (LUFA) and high unsaturated FA (HUFA) with similar fat content. The LUFA group mainly added fat powder (C16:0 > 90%), and the HUFA group mainly replaced fat powder with extruded flaxseed. The experiment lasted 26 d, the last 5 d of which, gas exchange in respiratory chambers was conducted to measure gas emissions. We found that an increase in the UFA in diet did not affect milk production (P > 0.05) and could align the profile of milk FAs more closely with modern human nutritional requirements. Furthermore, we found that increasing the UFA content in the diet lead to a decrease in the abundance of Methanobrevibacter in the rumen (|linear discriminant analysis [LDA] score| > 2 and P 2 and P < 0.05), which ultimately decreased CH4 production (P < 0.05). Our results illustrated the mechanism involving decreased CH4 production when fed a UFA diet in dairy cows. We believe that our study provides new evidence to explore CH4 emission reduction measures for dairy cows. (c) 2024 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/licenses/bync-nd/4.0/).

关键词： Methane emission Rumen metagenome Dairy cow Unsaturated fatty acid CONJUGATED LINOLEIC-ACID HOLSTEIN COWS EXTRUDED LINSEED MILK-PRODUCTION OIL METABOLISM DIETS BIOHYDROGENATION FERMENTATION N-3

Mesenchymal stromal cells modulate unfolded protein response and preserve β-cell mass in type 1 diabetes

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BIOCELL 2024年第7期48卷 1115-1126页

作者： siyuan liu YUAN ZHAO YU YU DOU YE QIAN WANG ZHAOYAN WANG ZUO LUAN Department of Pediatrics The Sixth Medical CenterChinese PLA General HospitalBeijing100037China

Introduction:Transplantation of mesenchymal stromal cells(MSCs)is a promising therapy for type 1 diabetes(T1D).However,whether the infused MSCs affect the endoplasmic reticulum stress or subsequent unfolded protein response inβcells remains ***:To investigate this,we induced early-onset T1D in non-obese diabetic mice using ***,T1D mice were randomly assigned to receive either MSCs or phosphate-buffered *** observed the in vivo homing of MSCs and assessed their effectiveness by analyzing blood glucose levels,body weight,histopathology,pancreatic protein expression,and serum levels of cytokines,proinsulin,and ***:Infused MSCs were found in the lungs,liver,spleen,and pancreas of T1D *** exhibited various effects,including reducing blood glucose levels,regulating immunity,inhibiting inﬂammation,increasingβ-cell areas,and reducing the expression of key proteins in the unfolded protein response *** serum proinsulin and C-peptide levels were signiﬁcantly higher in the MSCs treatment group than in the T1D model ***,there was no signiﬁcant difference in the biomarker ofβ-cell endoplasmic reticulum stress,the ratio of fasting serum proinsulin to C-peptide,between the two ***:Ourﬁndings reveal that MSCs infusion does not alleviate endoplasmic reticulum stress inβcells directly but modulates the unfolded protein response pathway to preserveβ-cell mass and function in T1D mice.

关键词： Type 1 diabetes Mesenchymal stromal cells Endoplasmic reticulum stress Unfolded protein response Non-obese diabetic mice

面向永磁同步电机无传感器控制的二阶改进扩展状态观测器

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西安交通大学学报 2024年第8期58卷 1-8页

作者：刘思源刘凌西安交通大学电气工程学院西安710049

针对传统扩展状态观测器(extended states observer,ESO)为保证收敛性和提升系统动态性能而增大矫正项增益,进而加剧对于高频噪声敏感性的问题,提出了一种面向永磁同步电机(permanent magnet synchronous motor,PMSM)无位置传感器控制... 详细信息

针对传统扩展状态观测器(extended states observer,ESO)为保证收敛性和提升系统动态性能而增大矫正项增益,进而加剧对于高频噪声敏感性的问题,提出了一种面向永磁同步电机(permanent magnet synchronous motor,PMSM)无位置传感器控制的改进扩展状态观测器(improved ESO,IESO)。结合PMSM扩展反电动势全阶模型,将扩展反电动势作为ESO扩展的状态;通过将低阶动态方程的输出作为高阶动态方程的输入的方法设计IESO,从而有效降低矫正项增益,进而减小系统对高频噪声的敏感性;在矫正项中引入饱和函数以限制高增益观测器可能引入的峰值效应,并进行了收敛性分析。数值仿真结果表明:相较于传统线性ESO,采用IESO后,PMSM无传感器控制系统在电机启动、调速及突加负载时动态性能均有提升,误差最大值减小,同时收敛速度加快约25%;在测量电流加入0.5 A随机高频噪声后,传统方法收敛时间增加了约25%,转速误差最大值增大了约40%,而IESO并没有显著增加,同时相较于传统方法,IESO的角度误差高频噪声减小了约60%,因而IESO能够显著抑制系统高频噪声。

关键词：永磁同步电机无位置传感器控制二阶状态观测器高增益观测器高频噪声抑制

Low-modal-crosstalk doped-fiber amplifiers in few-mode-fiber-based systems

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Photonics Research 2024年第8期12卷 1768-1775页

作者： SHUAILUO HUANG LEI SHEN GANG QIAO YUANPENG DING YUYANG GAO JIAN CUI BAOLONG ZHU siyuan liu MINGQING ZUO JINGLONG ZHU LEI ZHANG JIE LUO YONGQI HE ZHANGYUAN CHEN JUHAO LI State Key Laboratory of Advanced Optical Communication Systems and Networks Peking UniversityBeijing 100871China State Key Laboratory of Optical Fiber and Cable Manufacture Technology Yangtze Optical Fibre and Cable Joint Stock Limited CompanyWuhan 430073China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Department of Networks China Mobile Communications Group Co.Ltd.Beijing 100033China Department of Fundamental Network Technology China Mobile Research InstituteBeijing 100053China Pengcheng Laboratory Shenzhen 518055China

Independent light propagation through one or multiple modes is commonly considered as a basic demand for mode manipulation in few-mode fiber(FMF)-or multimode fiber(MMF)-based optical systems such as transmission links,optical fiber lasers,or distributed optical fiber ***,the insertion of doped-fiber amplifiers always kills the entire effort by inducing significant modal *** this paper,we propose the design of doped-fiber amplifiers in FMF-based systems adopting identical multiple-ring-core(MRC)index profiles for both passive and doped fibers to achieve low modal *** develop the direct-glass-transition(DGT)modified chemical vapor deposition(MCVD)processing for precise fabrication of few-mode erbium-doped fibers(FM-EDFs)with MRC profiles of both refractive index and erbium-ion doping ***,a few-mode erbium-doped-fiber amplifier(FM-EDFA)with a maximum gain of 26.08 dB and differential modal gain(DMG)of 2.3 dB is realized based on fabricated FM-EDF matched with a transmission FMF supporting four linearly polarized(LP)*** the insertion of the FM-EDFA,60+60 km simultaneous LP_(01)∕LP_(11)∕LP_(21)∕LP_(02)transmission without inter-modal multiple-input multiple-output digital signal processing(MIMO-DSP)is successfully *** proposed design of low-modal-crosstalk doped-fiber amplifiers provides,to our knowledge,new insights into mode manipulation methods in various applications.

关键词： fiber crosstalk amplifiers

基于双光子聚合3D打印的光纤法珀微波导腔制备及传感特性研究

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光学学报 2024年第2期44卷 120-126页

作者：陈茂庆刘思源蔡露刘强赵勇东北大学信息科学与工程学院辽宁沈阳110819 东北大学流程工业综合自动化国家重点实验室辽宁沈阳110819 河北省微纳精密光学传感与检测技术重点实验室河北秦皇岛066004

将光纤法布里-珀罗(法珀)微腔与微波导相结合,提出一种光纤法珀微波导腔高灵敏度折射率传感器。光纤法珀微腔可以将光场限制在微米量级的区域内,并对腔内的微波导结构起支撑保护作用;微波导在保证结构良好导光能力的同时,基于其强倏逝... 详细信息

将光纤法布里-珀罗(法珀)微腔与微波导相结合,提出一种光纤法珀微波导腔高灵敏度折射率传感器。光纤法珀微腔可以将光场限制在微米量级的区域内,并对腔内的微波导结构起支撑保护作用;微波导在保证结构良好导光能力的同时,基于其强倏逝场特性,进一步提升整体结构的折射率灵敏度。此外,基于飞秒激光双光子聚合高精度3D打印技术,可实现波导直径仅为2μm的光纤法珀微波导腔,并保证良好的制备重复性。实验结果表明:随着光纤法珀微波导腔传感器腔内液体折射率的增加,传感器的干涉光谱发生蓝移,在1.3346~1.3764折射率范围内灵敏度可达525.81 nm/RIU,与仿真获得折射率灵敏度(555.14 nm/RIU)结果接近;该传感器还展现了优良的线性响应特性,线性拟合系数可达0.9948;相比于传统无微波导的光纤法珀微腔结构,干涉光谱峰值提升了8.2 dB,折射率灵敏度提升了近4倍。

关键词：光纤传感器光纤法珀微波导腔微波导双光子聚合3D打印折射率

AI for organic and polymer synthesis

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Science China Chemistry 2024年第8期67卷 2461-2496页

作者： Xin Hong Qi Yang Kuangbiao Liao Jianfeng Pei Mao Chen Fanyang Mo Hua Lu Wen-Bin Zhang Haisen Zhou Jiaxiao Chen Lebin Su Shuo-Qing Zhang siyuan liu Xu Huang Yi-Zhou Sun Yuxiang Wang Zexi Zhang Zhunzhun Yu Sanzhong Luo Xue-Feng Fu Shu-Li You Center of Chemistry for Frontier Technologies Department of ChemistryZhejiang UniversityHangzhou 310027China Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China Guangzhou National Laboratory Guangzhou 510005China Center for Quantitative Biology Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China AI for Science(AI4S)-Preferred Program Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Department of Chemical Sciences National Natural Science Foundation of ChinaBeijing 100085China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Recent years have witnessed the transformative impact from the integration of artificial intelligence with organic and polymer synthesis. This synergy offers innovative and intelligent solutions to a range of classic problems in synthetic chemistry. These exciting advancements include the prediction of molecular property, multi-step retrosynthetic pathway planning, elucidation of the structure-performance relationship of single-step transformation, establishment of the quantitative linkage between polymer structures and their functions, design and optimization of polymerization process, prediction of the structure and sequence of biological macromolecules, as well as automated and intelligent synthesis platforms. Chemists can now explore synthetic chemistry with unprecedented precision and efficiency, creating novel reactions, catalysts, and polymer materials under the datadriven paradigm. Despite these thrilling developments, the field of artificial intelligence(AI) synthetic chemistry is still in its infancy, facing challenges and limitations in terms of data openness, model interpretability, as well as software and hardware support. This review aims to provide an overview of the current progress, key challenges, and future development suggestions in the interdisciplinary field between AI and synthetic chemistry. It is hoped that this overview will offer readers a comprehensive understanding of this emerging field, inspiring and promoting further scientific research and development.

关键词： organic synthesis polymer synthesis machine learning prediction chemical database automated synthesis