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Material analysis of the fatigue mechanism of rollers in tapered roller bearings

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Science China(Technological Sciences) 2018年第7期61卷 1003-1011页

作者： GUO Wei cao HongRui zi YanYang HE ZhengJia State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

Rolling contact fatigue is the main failure mechanism of tapered roller bearings. This study investigated the fatigue mechanism of rollers in a tapered roller bearing that failed in a run-to-failure test. Roller microstructure and crack morphology were investigated through scanning electron microscopy. A microhardness test was performed to investigate the strain hardening of the roller material induced by rolling contact fatigue. Results showed that microcavities and holes are important influential factors of crack initiation and propagation. Crack propagation angle affects crack morphology and propagation mode. Material strain hardening accelerates crack growth. Furthermore, roller misalignment causes uneven hardenability and severe damage to roller ends.

关键词： rolling contact fatigue mechanism crack propagation material microstructure roller misalignment

Material flow behavior modeling with consideration of size effects

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Rare Metals 2018年第11期37卷 995-1002页

作者： Zhen-Wu Ma zi-Yang cao Jin-Bin lu Hua Li Yuan-Jing Zhang Wei Liu Zhen Yin College of Mechanical Engineering Suzhou University of Science and TechnologySUzhou 215009China Suzhou Key Laboratory of Precision and Efficient Machining Technology Suzhou 215009China

Size effects make traditional forming theories infeasible in analyzing the micro-forming process, so it is necessary to develop an accurate material model to describe the material flow behavior with consideration of size effects. By studying the size effects of the flow behavior of H80 foils experimentally, it is found that the foil flow stress and strain hardening ability reduce significantly with the decrease of foil thickness. The reduction of the proportion of internal grains which own complete grain boundaries is the main cause of size effects of foil flow behavior. Moreover, grain refinement can reduce the size effects on material flow behavior. On these bases, a phenomenological material model has been developed to mathematically describe the material flow behavior with consideration of the effects of geometry size, grain size and strain hardening behavior. The reasonability and accuracy of this new model are verified by comparing the calculation values with experimental results in metal foil tensile and micro-bulk upsetting experiments. These experimental results and the proposed model lay a solid foundation for understanding and further exploring the material flow behavior in the micro-forming process.

关键词： Size effects Internal grains Material behavior Modeling

Peficitinib suppresses diffuse-type tenosynovial giant cell tumor by targeting TYK2 and JAK/STAT signaling

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Science China Life Sciences 2025年

作者： Shan lu Chenxi cao Wenjia Zhang Jiayi Li Jingli Yang zisheng Huang Zhijun Wu Baitao Liu Hongjie Huang Haijun Wang Yongjian Wang Dingge Liu Zhihua Zhang Kaiping Liu Gang Yang Xi Gong Hui Dai Yingjia Li Erdan Dong Xin Zhang Yan Zhang Haihe Laboratory of Cell Ecosystem Institute of Cardiovascular Diseases The First Affiliated Hospital of Dalian Medical University Institute of Cardiovascular Sciences School of Basic Medical Sciences Peking University Health Science Center Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalState Key Laboratory of Vascular Homeostasis and Remodeling Peking University Department of Sports Medicine Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing Key Laboratory of Sports Injuries Engineering Research Center of Sports Trauma Treatment Technology and Devices Ministry of Education State Key Laboratory of Membrane Biology Institute of Molecular Medicine College of Future Technology Peking University Peking University Health Science Centre Peking University Department of Immunology School of Basic Medical Sciences NHC Key Laboratory of Medical Immunology Peking University Research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital (Qingdao Municipal Hospital) School of Health and Life Sciences University of Health and Rehabilitation Sciences Research Unit of Medical Science Research Management/Basic and Clinical Research of Metabolic Cardiovascular Diseases Chinese Academy of Medical Sciences

Diffuse-type tenosynovial giant cell tumor(dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects. The Janus kinase(JAK)/signal transducer and activator of transcription(STAT) signaling plays a central role in rheumatoid arthritis(RA), a disease with similar characteristics as dTGCT, but its function in dTGCT remains *** fibroblast-like synoviocytes(FLS) and macrophages were isolated from 10 synovial tissue samples from dTGCT patients for the screening and validation of the five clinically approved JAK inhibitors to treat RA against dTGCT. Cell viability, cell death, inflammation and the activity of the JAK family members of cultured dTGCT FLS(both 2-D and 3-D) and macrophages were investigated for the efficacy of the JAK inhibitors. Here, we found that similar to RA, JAK/STAT signaling was markedly activated in the dTGCT synovium. Of the 5 JAK inhibitors, peficitinib was shown to have the most potency in addressing some of the pathological responses of dTGCT FLS and *** potency of peficitinib was much higher than pexidartinib, which is the only FDA-approved drug for dTGCT. Mechanistically, peficitinib inhibited tyrosine kinase 2(TYK2), a JAK family member necessary for the pathological progression of dTGCT FLS and macrophages. In summary, we not only revealed JAK/STAT(especially TYK2) signaling as the major mechanism underlying dTGCT, but also identified peficitinib as a promising drug against dTGCT.

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Triple negative breast cancer: special histological types and emerging therapeutic methods

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Cancer Biology & Medicine 2020年第2期17卷 293-306页

作者： lu cao Yun Niu Department of Pathology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerTianjin 300060China Department of Breast Cancer Pathology and Research Laboratory Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerTianjin 300060China

Triple negative breast cancer(TN BC)is a complex and malignant breast cancer subtype that lacks expression of the estrogen receptor(ER),progesterone receptor(PR)and human epidermal growth factor receptor 2(H ER2),thereby making therapeutic targeting *** is generally considered to have high malignancy and poor ***,patients diagnosed with certain rare histomorphologic subtypes of TNBC have better prognosis than those diagnosed with typical triple negative breast *** addition,with the discovery and development of novel treatment targets such as the androgen receptor(AR),PI3K/AKT/mTOR and AMPK signaling pathways,as well as emerging immunotherapies,the therapeutic options for TNBC are *** this paper,we review the literature on various histological types of TNBC and focus on newly developed therapeutic strategies that target and potentially affect molecular pathways or emerging oncogenes,thus providing a basis for future tailored therapies focused on the mutational aspects of TNBC.

关键词： Triple negative breast cancer pathological subtype androgen receptor immunotherapy targeted therapy

Role of the globus pallidus in motor and non-motor symptoms of Parkinson's disease

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Neural Regeneration Research 2025年第6期20卷 1628-1643页

作者： Yimiao Jiang Zengxin Qi Huixian Zhu Kangli Shen Ruiqi Liu Chenxin Fang Weiwei Lou Yifan Jiang Wangrui Yuan Xin cao Liang Chen Qianxing Zhuang Department of Physiology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Neurosurgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiChina National Center for Neurological Disorders ShanghaiChina Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration ShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institute of Brain ScienceFudan UniversityShanghaiChina

The globus pallidus plays a pivotal role in the basal ganglia circuit. Parkinson's disease is characterized by degeneration of dopamine-producing cells in the substantia nigra, which leads to dopamine deficiency in the brain that subsequently manifests as various motor and non-motor symptoms. This review aims to summarize the involvement of the globus pallidus in both motor and non-motor manifestations of Parkinson's disease. The firing activities of parvalbumin neurons in the medial globus pallidus, including both the firing rate and pattern, exhibit strong correlations with the bradykinesia and rigidity associated with Parkinson's disease. Increased beta oscillations, which are highly correlated with bradykinesia and rigidity, are regulated by the lateral globus pallidus. Furthermore,bradykinesia and rigidity are strongly linked to the loss of dopaminergic projections within the cortical-basal ganglia-thalamocortical loop. Resting tremors are attributed to the transmission of pathological signals from the basal ganglia through the motor cortex to the cerebellum-ventral intermediate nucleus circuit. The cortico–striato–pallidal loop is responsible for mediating pallidi-associated sleep disorders. Medication and deep brain stimulation are the primary therapeutic strategies addressing the globus pallidus in Parkinson's disease. Medication is the primary treatment for motor symptoms in the early stages of Parkinson's disease, while deep brain stimulation has been clinically proven to be effective in alleviating symptoms in patients with advanced Parkinson's disease,particularly for the movement disorders caused by levodopa. Deep brain stimulation targeting the globus pallidus internus can improve motor function in patients with tremordominant and non-tremor-dominant Parkinson's disease, while deep brain stimulation targeting the globus pallidus externus can alter the temporal pattern of neural activity throughout the basal ganglia–thalamus network. Therefore, the comp

关键词： anxiety basal ganglia bradykinesia deep brain stimulation depression globus pallidus externus globus pallidus internus lateral globus pallidus medial globus pallidus neural circuit Parkinson's disease

Synthesis of hollow spherical nickel oxide and its gas-sensing properties

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Rare Metals 2021年第6期40卷 1622-1631页

作者： Wang-Chang Geng Xin-Rou cao Shi-lu Xu Jiang-Hua Yang Natasha Babar zi-Jun He Qiu-Yu Zhang School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China School of Automation Northwestern Polytechnic UniversityXi’an 710072China

Semiconductor metal oxides have attracted wide attention in the area of gas sensor due to that they have unique advantages in the rapid and accurate detection of harmful gases.A simple strategy is to synthesize porous NiO hollow microspheres via a simple hydrothermal method with trisodium citrate as structure guide agent is presented in this paper,and the shell of the microsphere is composed of porous and lamellar assembly *** cavity proportion can be adjusted by changing the amount of trisodium citrate.A reasonable mechanism was proposed to explain the formation of porous NiO hollow *** a gas-sensing material,porous NiO hollow microspheres show excellent gas selectivity and rapid response recovery time for n-butyl alcohol *** the content of trisodium citrate was 0.10 g,the synthesized hollow sphere NiO had the highest response value(25.6)to 100×10^(-6) of n-butyl alcohol at 300℃ and the response and recovery times were only 68 and 10 s.

关键词： Nickel oxide Porous structure Hollow spheres Gas sensor n-butyl alcohol

Asymmetric interfacial engineering regulated charge distribution on Ru/Ni-N-C sites for efficient hydrogen evolution reaction in alkaline and seawater electrolytes

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Science China Chemistry 2025年

作者： Rui Yu Xi cao Chengyang Zhu Qingqing Chen ziyi Yan Binbin Jiang Junjie Mao Xianwen Wei Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes College of Chemistry and Materials ScienceAnhui Normal University Anhui Provincial Key Laboratory of Advanced Catalysis and Energy Materials School of Chemistry and Chemical Engineering Anqing Normal University School of Chemistry and Chemical Engineering Anhui University of Technology

Developing highly efficient and cost-effective electrocatalysts for hydrogen evolution reaction（HER） is grandly challenging in alkaline and alkaline seawater electrolytes. Herein, the asymmetric interfacial active sites with Ru nanoparticles and Ni single atoms in Ru/Ni-N-C were designed through a solvothermal-pyrolysis process. Constructing highly asymmetric interfacial active sites with a strong electron delocalization effect significantly improves HER kinetics. As expected, Ru/Ni-N-C requires low overpotentials with around 20 mV at 10 mA cm-2and robust durability over 48 h in alkaline and alkaline seawater *** at 200 mA cm-2, the overpotentials are close to 100 mV in both above electrolytes for Ru/Ni-N-C. Density function theory calculation results suggest that the asymmetric interface between Ru nanoparticle and Ni-N-C could accelerate the dissociation of water molecules and modulate the hydrogen species, consequently improving the HER performances. This work opens a unique approach for constructing advanced materials for energy conversion.

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Quantification of polarization distribution from polarizing light microscopy images of ferroelectric single crystals

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Journal of Materials Science & Technology 2023年第30期161卷 1-9页

作者： Jinhui Fan Xiaoyan lu Wenwu cao Functional Materials and Acousto-optic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China School of Civil Engineering Harbin Institute of TechnologyHarbin 150001China Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

Qualification of polarization can be realized either on a macroscopic scale as an average property by P-E hysteresis measurements or on a nano/micro scale by piezoelectric force microscopy,transmission electron microscopy,scanning electron microscopy,and so ***,visualization and qualification of polarization distribution in the micron to millimeter scale is still a *** light microscopy(PLM)is often used in the study of ferroelectric domain structures mainly for domain patterns.A phe-nomenon called“chromatic polarization”has been observed in transparent ferroelectric crystals by using a crossed-PLM system viewed with white light,which contains rich information about local polariza-tion *** this study,an automatic full-angle light intensity detection(AFALID)algorithm com-bined with colorimetry is developed to analyze the distribution of nonuniform local spontaneous polar-ization distribution in transparent ferroelectric single ***-dependent spontaneous po-larizations from the color analysis for PMN-0.36PT single crystals with single tetragonal domain state are in good coincidence with those extracted from temperature-dependent hysteresis loops and pyroelectric current *** further apply this method to quantify the nonuniform domain distributions with *** non-contact and non-destructive characterization can provide fast and au-tomatic detection of polarization distributions in ferroelectric materials.

关键词： Polarizing light microscopy Polarization distribution Ferroelectric single crystals Chromatic polarization

Distributed Adaptive Output Consensus of Unknown Heterogeneous Non-Minimum Phase Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 997-1008页

作者： Wenji cao lu Liu Gang Feng Department of Biomedical Engineering City University of Hong KongHong Kong SARChina

This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed *** dynamics of followers are allowed to be non-minimum phase with unknown arbitrary individual relative *** is contrary to many existing works on distributed adaptive control schemes where agent dynamics are required to be minimum phase and often of the same relative degree.A distributed adaptive pole placement control scheme is developed,which consists of a distributed observer and an adaptive pole placement control *** is shown that under the proposed distributed adaptive control scheme,all signals in the closed-loop system are bounded and the outputs of all the followers track the output of the leader *** effectiveness of the proposed scheme is demonstrated by one practical example and one numerical example.

关键词： Adaptive pole placement control heterogeneous multi-agent systems leader-following output consensus non-minimum phase