检索结果-南通市图书馆

High-speed imaging observation on molten bridges of AgNi10 electrical contact material

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2023年第1期42卷 336-345页

作者： jing-hong chen Song chen Ming Xie Jie-Qiong Hu Sai-Bei Wang State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metal Kunming Institute of Precious MetalsKunming650106China

The electrical contact-high-speed imaging experimental system was developed to investigate the molten bridge phenomena of AgNi10 electrical contact *** dimension of molten bridges was measured along with the measurement of waveforms in the contact voltage under the load of direct current(DC) 6 V(8-20 A)and breaking speed of 50.0 mm·s^(-1).A part of the observed results was presented as well as surface morphology of the contacts after electrical contact behavior,which shows some interesting and new *** bridges and arc could exist *** stable molten bridge looks like cylindrical shape and then becomes needle tip at its rupture,the diameter and length of molten bridges both increase with the increase in current and the growth gradient of the diameter is larger than that of the *** morphology and elemental distribution of the contact surface are changed by the behavior of electrical contact.

关键词： Molten bridge High-speed imaging Arc AgNi10 electrical contact material

Self-Organized Public-Key Management for Mobile Ad Hoc Networks Based on a Bidirectional Trust Model

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2006年第1期11卷 188-192页

作者： FU Cai hong Fan LI Rui-xian hong Liang chen jing College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

In traditional networks , the authentication is performed by certificate authoritys（CA）,which can＇t be built in distributed mobile Ad Hoc Networks however. In this pa per, we propose a fully self-organized public key management based on bidirectional trust model without any centralized authority that allows users to generate their public-private key pairs, to issue certificates, and the trust relation spreads rationally according to the truly human relations. In contrast with the traditional self-organized public-key management, the average certificates paths get more short, the authentication passing rate gets more high and the most important is that the bidirectional trust based model satisfys the trust re quirement of hosts better.

关键词： Ad Hoc networks self-organize bidirectional trust public key management.

T-2 toxin-induced apoptosis involving Fas,p53,Bcl-xL,Bcl-2,Bax and caspase-3 signaling pathways in human chondrocytes

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第6期9卷 455-463页

作者： jing-hong chen Jun-ling CAO Yong-lie CHU Zhi-lun WANG Zhan-tian YANG hong-lin WANG Ministry of Education Key Laboratory of Environment and Genes related to Diseases Institute of Endemic Diseases School of Medicine Xi ＇an Jiaotong University Xi ＇an 710061 China

Objective:To investigate the effects of T-2 toxin on expressions of Fas,p53,Bcl-xL,Bcl-2,Bax and caspase-3 on human ***:Human chondrocytes were treated with T-2 toxin(1～20 ng/ml)for 5 ***,p53 and other apoptosis-related proteins such as Bax,Bcl-2,Bcl-xL,caspase-3 were determined by Western blot analysis and their mRNA expressions were determined by reverse transcriptase-polymerase chain reaction(RT-PCR).Results:Increases in Fas,p53 and the pro-apoptotic factor Bax protein and mRNA expressions and a decrease of the anti-apoptotic factor Bcl-xL were observed in a dose-dependent manner after exposures to 1～20 ng/ml T-2 toxin,while the expression of the anti-apoptotic factor Bcl-2 was ***,T-2 toxin could also up-regulate the expressions of both pro-caspase-3 and caspase-3 in a dose-dependent ***:These data suggest a possible underlying molecular mechanism for T-2 toxin to induce the apoptosis sig- naling pathway in human chondrocytes by regulation of apoptosis-related proteins.

关键词： Apoptosis Apoptosis-related proteins Chondrocyte T-2 toxin

Mars exploration——In situ K-Ar dating of jarosite

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第3期67卷 641-656页

作者： jing YANG Dewen ZHENG Ying WU hong chen Li YANG Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

Arbuscular mycorrhizae status of host plant affects offspring's phenotype and transcriptome expression in a low-phosphorus environment

在线全文

学校读者我要写书评

暂无评论

JOURNAL OF PLANT ECOLOGY 2024年第2期17卷 173-187页

作者： Liu, Shijun Xu, jing Huang, hong Tang, Jianjun chen, Xin Liaoning Normal Univ Sch Life Sci Key Lab Plant Biotechnol Liaoning Prov Dalian 116081 Peoples R China Zhejiang Univ Coll Life Sci Hangzhou 310058 Peoples R China Zhejiang Acad Agr Sci Inst Environm Resources & Soil Fertilizers Hangzhou 310021 Peoples R China

Although the effects of arbuscular mycorrhizal fungi (AMF) on host plants have been well documented, whether the effects of AMF on parental generations affect offspring performance is not fully clear. We conducted a common garden experiment to determine whether AMF status of host plants (Medicago truncatula) affects phenotype and transcriptome expression of their offspring. Seeds from four type parental treatments (low-phosphorus (P) soil without AMF, low-P soil with AMF, high-P soil without AMF and high-P soil with AMF) were grown under low-P (LPS) and normal-P soil (OHS) conditions. The flowering pattern of LP offspring was similar to their parents, such that plants with AMF flowered earlier than those without AMF under OHS condition but were opposite under LPS condition. The transcriptome differential analysis showed that some differential transcripts (45 for parental plants growing under low-P condition and 3 for parental plants growing under high-P condition) expression patterns between offspring were comparable, and that only affected by parental AMF status regardless of the P environment that offspring was grown. Others (146 for parental plants growing under low-P condition and 2 for parental plants growing under high-P condition), however, were affected both by the parental AMF status and the offspring P environment. In addition, the number of differential transcripts between offspring whose parental plants grew under high-P condition was far less than under low-P condition. These results indicate that AMF may not only affect the current generation of host plants but also affect the offspring especially when their parents have experienced a stressful environment.

关键词： arbuscular mycorrhizal fungi low-phosphorus environment flowering pattern transgenerational effects transcriptome differential analysis PHOSPHATE DEFICIENCY ARABIDOPSIS ROOTS FUNGI COLONIZATION RESPONSES STRESS INHERITANCE

Expressions of Nucleoside Diphosphate Kinase (nm23) in Tumor Tissues are Related with Metastasis and Length of Survival of Patients with Hepatocellular Carcinoma

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2010年第4期23卷 267-272页

作者： RUN AN JIE MENG QI SHI XIAO-XIA DAI jing-hong chen YAN-JUN LEI BING SHAN chen GAO YONG-LIE CHU XIAO-PING DONG School of Medicine Xi'an Jiao-Tong University Xi'an 710061 Shanxi China State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Ying-Xin Rd 100 Beijing 100052 China

Objective To evaluate the relationship of expressions of nucleoside diphosphate kinase （nm23） and proliferating cell nuclear antigen （PCNA）, as well as apoptosis, with the prognosis of HCC patients by analyzing their pathological and clinical data. Methods The expressions of nm23 and PCNA were analyzed by immunohistochemistry and the apoptotic phenomena were detected by TUNEL technique in the liver samples from 43 HCC tissues, 39 para-neoplastic tissues, and 10 normal tissues. The mean apoptosis index （AI） and proliferative index （PI） in individual sample were calculated. Results As shown by the detection, 32.6% of carcinomas had negative nm23 signal in tumor tissues, whereas all para-neoplastic and normal tissues had positive nm23. The AI in nm23 positive HCC was significantly higher than that in nm23 negative one, with statistical difference （P0.05）. Furthermore, the expressions of nm23, and the values of AI and PI were contrastively analyzed with some main pathological and clinical data of HCC. It revealed that HCC with extrahepatic metastasis showed remarkable correlation with the negative nm23 （P=0.013） and higher PI values of HCC （P=0.015）. The disease-free survival in HCC patients with negative nm23 expression was significantly poorer than that in patients with positive nm23 expression. Conclusion These data suggest that expressions of nm23 protein in tumor tissues are correlated with occurrences of metastasis and length of survival of the HCC patients, which may be an indicator for their prognosis.

关键词： Hepatocellular carcinoma nm23 PCNA Apoptosis Prognosis

Estrogen augmented visceral pain and colonic neuron modulation in a double-hit model of prenatal and adult stress

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第30期27卷 5060-5075页

作者： jing-hong chen Ying Sun Pei-Jun Ju Jin-Bao Wei Qing-Jie Li John H Winston Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghai 200030China Department of Internal Medicine University of Texas Medical BranchGalvestonTX 77555United States

BACKGROUND Chronic stress during pregnancy may increase visceral hyperalgesia of offspring in a sex-dependent *** adult stress in offspring will increase this *** on the evidence implicating estrogen in exacerbating visceral hypersensitivity in female rodents in preclinical models,we predicted that chronic prenatal stress(CPS)+chronic adult stress(CAS)will maximize visceral hyperalgesia;and that estrogen plays an important role in colonic *** The aim was to illuminate the role of estrogen in colonic hyperalgesia and its underlying *** We established a CPS plus CAS rodent model in which the balloon was used to distend the *** single-fiber recording in vivo and patch clamp experiments in vitro were used to monitor the colonic neuron’s *** reverse transcription-polymerase chain reaction,western blot,and immunofluorescence were used to study the effects of CPS and CAS on colon primary afferent *** used ovariectomy and letrozole to reduce estrogen levels of female rats respectively in order to assess the role of estrogen in female-specific enhanced primary afferent *** Spontaneous activity and single fiber activity were significantly greater in females than in *** enhanced sensitization in female rats mainly came from lowthreshold *** significantly increased single-unit afferent fiber activity in L6-S2 dorsal roots in *** was further enhanced by *** addition,the excitability of colon-projecting dorsal root ganglion(DRG)neurons increased in CPS+CAS rats and was associated with a decrease in transient Atype K+*** with ovariectomy,treatment with the aromatase inhibitor letrozole significantly reduced estrogen levels in female rats,confirming the gender ***,mice treated with letrozole had decreased colonic DRG neuron *** intrathecal infusion of estrogen increased brain-derived neurotrophic factor(BDNF)p

关键词： Chronic prenatal stress Estrogen Visceral pain Neuronal sensitization Excitability Letrozole

Noise-Tolerant ZNN-Based Data-Driven Iterative Learning Control for Discrete Nonaffine Nonlinear MIMO Repetitive Systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 344-361页

作者： Yunfeng Hu Chong Zhang Bo Wang jing Zhao Xun Gong Jinwu Gao hong chen State Key Laboratory of Automotive Simulation and Control Jilin UniversityJilin UniversityChangchun 130025China College of Communication Engineering Jilin UniversityJilin UniversityChangchun 130025China Department of Electromechanical Engineering University of MacaoMacao 999078China School of Artificial Intelligence Jilin UniversityChangchun 130012China IEEE College of Electronics and Information Engineering Tongji UniversityShanghai 200092China

Aiming at the tracking problem of a class of discrete nonaffine nonlinear multi-input multi-output(MIMO) repetitive systems subjected to separable and nonseparable disturbances, a novel data-driven iterative learning control(ILC) scheme based on the zeroing neural networks(ZNNs) is proposed. First, the equivalent dynamic linearization data model is obtained by means of dynamic linearization technology, which exists theoretically in the iteration domain. Then, the iterative extended state observer(IESO) is developed to estimate the disturbance and the coupling between systems, and the decoupled dynamic linearization model is obtained for the purpose of controller synthesis. To solve the zero-seeking tracking problem with inherent tolerance of noise,an ILC based on noise-tolerant modified ZNN is proposed. The strict assumptions imposed on the initialization conditions of each iteration in the existing ILC methods can be absolutely removed with our method. In addition, theoretical analysis indicates that the modified ZNN can converge to the exact solution of the zero-seeking tracking problem. Finally, a generalized example and an application-oriented example are presented to verify the effectiveness and superiority of the proposed process.

关键词： Adaptive control control system synthesis data-driven iterative learning control neurocontroller nonlinear discrete time systems

MADRL-based UAV swarm non-cooperative game under incomplete information

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen WANG Fan LIU chen hong jing GUO Lin ZHAO Jian XUE Ning HE School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of Q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium