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Journal of Modern Transportation 2011年第3期19卷 168-175页

作者： chang chun hsieh Cuihua CHENG Chuan KE Yong ZHAO Superconductivity and New Energy Center （SNEC） Southwest Jiaotong University Chengdu 610031 China Superconductivity Research Group School of Materials Science and Engineering University of New South Wales Sydney 2052 NSW Australia

A theoretical model of describing the electromagnetic and thermal dynamics of high-Tc superconducting bulks in a high-Tc superconducting Maglev system is built *** model contains the effects of hysteresis-type loss,flux flow,flux creep,and thermal diffusion on the superconducting bulks in the Maglev *** the first stage of this study,the behavior of magnetic and electric fields,as well as the distribution energy flow density in the superconducting bulk is *** results show that the flux flow and thermal diffusion affect the behaviors of the electromagnetic field in the high-Tc superconducting bulks in different ways;however,both of them contribute significantly to the energy dissipation of the superconducting bulks when they are used in the Maglev train.

关键词： YBCO AC losses critical frequency self-heating

Enhancement of flux pinning in GdBa_2Cu_3O_(7-y) bulks prepared by nanoparticle-powder-assisted method

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Journal of Modern Transportation 2011年第2期19卷 104-109页

作者： C.H. CHENG chang chun hsieh Chuan KE H. ZHANG C.C. SORRELL Superconductivity Research Group School of Materials Science and Engineering University of New South Wales Sydney 2052 NSW Australia Key Laboratory for Levitation Technology and Maglev Trains Ministry of Education of China Superconductivity and New Energy Center （SNEC） Southwest Jiaotong University Chengdu 610031 China Department of Physics Peking University Beijing 100871 China

High quality GdBa2Cu307-y （Gd123） textured bulks with Nd2BaCuO5 （Nd211） nanoparticle precipitations have been fabricated by a nanoparticle-powders-assisted MTG （melt-textured-growth） technique. The high density nanoscale flux pinning sites were introduced into Gd123 by mixing Nd211 nanoparticle powders （about 20-50 nm） with Gd123 nano-precursors before the MTG process. Microstructural analyses reveal that a large number of Nd211 nanoparticles with a size around 50-150 nm were inserted in the Gd123 matrix, forming a kind of superconducting nanocomposites. The critical current density at 77 K is systematically increased and the flux pinning behavior is significantly improved. The scaling behavior of the flux pinning force shows a magnetic field dependent feature with a peak located at hp≈0.4. This may be the fingerprint of melt-textured 123 compounds, which cannot be interpreted by the simple superposition of different types of elementary pinning sources.

关键词： flux pinning GdBa2Cu307-y nanoparticle-powder assisted processing critical current density

Analysis of Nitrate Sources in Different Rivers Flowing into the Sea Based on Nitrogen and Oxygen Isotopes

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Huanjing Kexue/Environmental Science 2025年第3期46卷 1371-1381页

作者： Xin, Zhuo-Hang chang, Peng-Juan Liu, Zhi-Hong Song, chang-chun Department of Hydraulic Engineering Dalian University of Technology Dalian116024 China

The nitrogen flux from terrestrial input is the primary source of nitrogen load in estuarine areas，leading to ecological issues，such as coastal eutrophication and hypoxia. Systematically identifying the nitrogen sources from different rivers draining into the sea is a prerequisite for controlling the nitrogen pollution in estuarine areas. Based on the nitrogen and oxygen isotopes of 179 sampling sites across 12 rivers in Liaoning and Hebei Provinces，the nitrate sources of different rivers were systematically identified. Moreover，the stable isotope analysis in the R（SIAR）model was employed to quantitatively calculate the contribution rates of various pollution sources to river nitrate. The results indicated that nitrification was the primary process of nitrate transformation. For all 12 rivers，the contribution rate of animal manure and sewage ranged from 13.9% to 90.1% and that of soil nitrogen ranged from 4.3% to 54.0%. Additionally，for the Liaojiawa River，Xuanhui River，and Nanpai River in Cangzhou City，agricultural fertilizers were observed to have relatively high contribution rates，ranging from 25.2% to 64.4%. Overall，the nitrogen loads in these 12 rivers were highly disturbed by anthropogenic activities and the primary sources of nitrate varied among different rivers. Therefore implementing targeted and differentiated control measures in watershed nitrogen control and management is important. © 2025 Science Press. All rights reserved.

关键词： Eutrophication

Scapular metastasis from acinic cell carcinoma of parotid gland:A case report

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World Journal of Clinical Cases 2025年第9期13卷 41-46页

作者： Deng-Qun Sun chang-chun Chen Duo-An Zheng Hai-Yan Xing Xue Peng Department of General Surgery The Chinese People’s Armed Police Forces Anhui Provincial Corps HospitalHefei 230001Anhui ProvinceChina Department of Radiology The Chinese People’s Armed Police Forces Anhui Provincial Corps HospitalHefei 230001Anhui ProvinceChina Department of Pathology The Chinese People’s Armed Police Forces Anhui Provincial Corps HospitalHefei 230001Anhui ProvinceChina

BACKGROUND Acinic cell carcinoma(ACC)is a malignant epithelial neoplasm that commonly occurs in the parotid *** is known to have a high recurrence rate and the potential to metastasize to the lung or cervical lymph ***,few cases of ACC with bone metastasis have been reported in the medical *** SUMMARY The clinical significance of this case report lies in the unique site of occurrence of the metastasis:To the best of our knowledge,this report is the only literature documenting ACC arising in a shoulder *** Unusual presentations of uncommon malignancies can present diagnostic challenges for both surgeons and *** is important to be aware of these rare occurrences in order to provide the best possible treatment for patients.

关键词： Acinic cell carcinoma Shoulder mass Scapular Metastasis Case report

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen chang Hong-Yu Tang chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines(Chinese Academy of Sciences) Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Shenzhen Bay Laboratory Shenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest ChinaKunming Institute of BotanyChinese Academy of SciencesKunming 650201China Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesBeijing 100730China

In the intricate process of natural product biosynthesis,a metabolon can enhance metabolic flux by associating sequential enzymes.A fungal metabolon,comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G,is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide *** notoamide E as a substance,Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation,followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium ***,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol *** provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

基于改进无模型自适应控制的挖掘机无人作业方法

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控制与决策 2025年第3期40卷 785-793页

作者：陈阔刘畅骆曦华长春蔡登胜耿波燕山大学电气工程学院广西柳工股份有限公司

针对挖掘机无人作业,考虑挖掘机工作装置液压系统的强非线性、参数不确定性、时变载荷和高能耗问题,提出一种改进的全格式动态线性化无模型自适应控制方法.首先,通过分析驱动空间与任务空间的映射关系,将挖掘机铲斗齿尖的轨迹跟踪问题... 详细信息

针对挖掘机无人作业,考虑挖掘机工作装置液压系统的强非线性、参数不确定性、时变载荷和高能耗问题,提出一种改进的全格式动态线性化无模型自适应控制方法.首先,通过分析驱动空间与任务空间的映射关系,将挖掘机铲斗齿尖的轨迹跟踪问题转化为液压缸活塞杆伸缩量跟踪问题;其次,为了保证轨迹的连续性和平顺性、降低计算复杂程度、减少系统在启动和停止时的不稳定性,利用5次NURBS曲线插值方法对挖掘轨迹进行规划;进一步,设计改进的全格式动态线性化无模型自适应控制算法实现挖掘机无人作业,为减少能量消耗在输入准则函数中引入能量函数的惩罚项,在确保良好跟踪精度的同时实现最优能耗;最后,对所提方法进行实例仿真,验证该方法的可行性和优越性.

关键词：液压挖掘机无人作业轨迹跟踪无模型自适应控制数据驱动节能控制

基于全驱系统方法的AUV鲁棒自适应轨迹跟踪控制

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控制与决策 2025年第1期40卷 285-291页

作者：王鹏钱承张柳柳华长春燕山大学电气工程学院河北秦皇岛066004 燕山大学河北省智能康复及神经调控重点实验室河北秦皇岛066004

针对存在执行器故障、外界干扰和模型不确定的自主式水下潜航器系统(autonomous underwater vehicle,AUV),提出基于全驱系统(fully actuated system,FAS)方法的鲁棒自适应轨迹跟踪误差受限控制策略,使AUV能够渐近跟踪目标信号.首先,将... 详细信息

针对存在执行器故障、外界干扰和模型不确定的自主式水下潜航器系统(autonomous underwater vehicle,AUV),提出基于全驱系统(fully actuated system,FAS)方法的鲁棒自适应轨迹跟踪误差受限控制策略,使AUV能够渐近跟踪目标信号.首先,将跟踪误差相关的归一化函数和障碍函数与时变尺度函数相结合,提出误差受限全驱系统方法;其次,将径向基函数神经网络(radial basis function neural networks,RBFNNs)与误差受限全驱系统方法相结合处理系统中的不确定模型;进一步,设计自适应补偿机制处理执行器故障;再次基于Lyapunov稳定性理论证明轨迹跟踪误差渐近收敛于零;最后,通过仿真结果验证所设计的鲁棒自适应轨迹跟踪误差受限控制器的有效性.

关键词：全驱系统方法鲁棒控制自适应控制神经网络轨迹跟踪控制

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平台劳动者数据财产权的正当性及规范构造

河南财经政法大学学报 2025年第1期40卷 88-102页

作者：常春中国人民大学法学院北京100872

作为数据来源者的平台劳动者能否享有数据财产权,事关其财产权益保障、数据基础制度完善及新质生产力的培育。根据劳动赋权理论和数据制度公平的要求,以及出于维护人格完整性和个人信息财产权益的需要,平台劳动者应享有数据财产权。平... 详细信息

作为数据来源者的平台劳动者能否享有数据财产权,事关其财产权益保障、数据基础制度完善及新质生产力的培育。根据劳动赋权理论和数据制度公平的要求,以及出于维护人格完整性和个人信息财产权益的需要,平台劳动者应享有数据财产权。平台劳动者数据财产权包括使用、收益和处分三项权能,难以归入民法典财产权体系。因此,需要在立法上为平台劳动者创设一项名为数据财产权的新型权利,并构建法定债权规则使平台劳动者有权请求数据处理者给付法定金钱对价;构建数据访问规则保障平台劳动者查阅、复制和使用数据;设立谦抑性的数据删除和转移规则,确保平台劳动者可以在法定情形下删除或转移数据。

关键词：平台劳动者数据财产权数据制度公平权能新质生产力

Selenoprotein P1 as a biomarker of insulin resistance in pediatric obesity:Insights and implications

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World Journal of Clinical Pediatrics 2025年第1期14卷 1-5页

作者： chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng Department of Medical Education Linkou Chang Gung Memorial HospitalTaoyuan 33305TaiwanChina Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei 23561TaiwanChina Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002TaiwanChina Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404328TaiwanChina

This editorial discusses the findings of Elbarky et al on the role of selenoprotein P1(SEPP1)in pediatric obesity and insulin *** study uncovered si-gnificantly lower SEPP1 Levels in children who were obese compared with hea-lthy peers,demonstrating a negative correlation between SEPP1 levels and mea-sures of adiposity and insulin *** findings suggest that SEPP1 is a biomarker useful in the early identification of insulin resistance in pediatric *** editorial emphasizes the clinical implications of the study and calls for further research to validate and explore the role of SEPP1 in metabolic health.

关键词： Selenoprotein P1 Pediatric obesity Insulin resistance Biomarkers Metabolic health

Elafibranor:A promising therapeutic approach for liver fibrosis and gut barrier dysfunction in alcohol-associated liver disease

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World Journal of Gastroenterology 2025年第3期31卷 123-126页

作者： chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng Department of Medical Education Linkou Chang Gung Memorial HospitalTaoyuan 33305TaiwanChina Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei City 23561TaiwanChina Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002TaiwanChina Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404328TaiwanChina

This article discusses the recent study written by Koizumi et ***-associated liver disease(ALD)is a major cause of liver-related morbidity and mortality,which is driven by complex mechanisms,including lipid accumulation,apoptosis,and inflammatory responses exacerbated by gut barrier *** study explored the therapeutic potential of elafibranor,a dual peroxisome proliferatoractivated receptor alpha/delta *** clinical trials,elafibranor has shown promise for the treatment of other liver conditions;however,its effects on ALD remain *** authors’findings indicate that elafibranor significantly reduced liver fibrosis and enhanced gut barrier integrity in patients with *** positive effects of elafibranor are mediated through multiple *** promotes lipid metabolism,reduces oxidative stress,and inhibits inflammatory responses by restoring gut barrier ***,it improves hepatocyte function by enhancing autophagic and antioxidant capacity,and it mitigates inflammation by suppressing the lipopolysaccharide/toll-like receptor 4/nuclear factor kappa B signaling *** findings indicate that elafibranor has promising clinical *** addition,the study highlights elafibranor’s potential as a therapeutic agent for liver diseases,particularly *** article underscores the importance of understanding the mechanistic pathways underlying ALD and suggests directions for future research aimed at elucidating the benefits and limitations of elafibranor.

关键词： Elafibranor Liver fibrosis Gut barrier function Alcohol-associated liver disease Peroxisome proliferatoractivated receptor agonists