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Highly oxygenated dihydrostilbenoids and flavones from the aerial part of Glycyrrhiza uralensis and their antimicrobial activities

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Science of Traditional Chinese Medicine 2024年第4期2卷 291-302页

作者： Xinyi Wei Junfei Zhou Liping Zeng Mingming Xu chuntao che Jin’ao Duan Hui Yan Hongkai Bi Ming Zhao Jiangsu Collaborative Innovation Centre of Chinese Medicinal Resources Industrialization National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative MedicineSchool of PharmacyNanjing University of Chinese MedicineNanjingChina Department of Pharmaceutical Sciences College of Pharmacythe University of Illinois ChicagoChicagoILUSA Department of Pathogen Biology Jiangsu Key Laboratory of Pathogen BiologyNanjing Medical UniversityNanjingChina

Background:Multidrug-resistant bacteria(MDRB)represent a significant global challenge due to their high mortality rates,substantial economic burden,and rapid *** triple or quadruple therapies have demonstrated limited efficacy as a result of increasing drug ***,it is urgent to develop novel anti-MDRB drugs with high efficiency and low ***:To isolate and identify the dihydrostilbenoids and flavones from the aerial part of Glycyrrhiza uralensis(Fabaceae)and to screen their antimicrobial *** and methods:The aerial part of *** was extracted with 75%aqueous *** crude extract was repeatedly isolated by macroporous resin,silica gel,Sephadex LH-20,C_(18)-MPLC,and MCI-MPLC,which were then purified by semipreparative RPHPLC to obtain monomer *** structures of the isolates were assigned by a combination of optical rotations,UV spectra,nuclear magnetic resonance,and high-resolution electrospray ionization mass spectrometry,and the absolute configurations of compounds 2,3,and 7 were further confirmed by electronic circular dichroism ***,we investigated their antimicrobial activities by the broth microdilution ***:Seventeen previously undescribed phenolic compounds(1–17)and 26 known analogs(18–43),including dihydrostilbenoids,flavones,and dihydroflavones,were identified from the aerial part of *** vitro,antimicrobial bioassays demonstrated that compound 31 displayed the strongest inhibitory effect against 4 drug-resistant Helicobacter pylori strains(MIC=2–4μg/mL),comparable to metronidazole(MIC=1–32μg/mL).Additionally,compounds 10,13,and 15 demonstrated bactericidal activity against Staphylococcus aureus(MIC=4μg/mL),while compounds 15 and 22 exhibited inactivation effects against Mycobacterium smegmatis,Enterococcus faecium,and ***(MIC=4–8μg/mL).Conclusions:These monomeric compounds with antimicrobial activities were isolated from the aerial parts

关键词： Phenolic compounds Electronic circular dichroism(ECD) Bactericidal activity Helicobacter pylori

柱前衍生化HPLC法测定黄芪中黄芪甲苷的含量

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天然产物研究与开发 2000年第4期12卷 17-22页

作者：姚美村齐莹车镇涛毕开顺罗旭沈阳药科大学药物分析研究室沈阳110015 香港中文大学中医学院

目的 :建立黄芪中黄芪甲苷的柱前衍生化高效液相色谱测定法 ,并用该法对不同产地黄芪中黄芪甲苷的含量进行比较。方法 :以吡啶 -苯甲酰氯 ( 2 .5∶ 1)为衍生化试剂 ,对黄芪甲苷分子中的羟基进行苯甲酰化 ,以甲醇 -四氢呋喃 -水 ( 90∶ 4... 详细信息

目的 :建立黄芪中黄芪甲苷的柱前衍生化高效液相色谱测定法 ,并用该法对不同产地黄芪中黄芪甲苷的含量进行比较。方法 :以吡啶 -苯甲酰氯 ( 2 .5∶ 1)为衍生化试剂 ,对黄芪甲苷分子中的羟基进行苯甲酰化 ,以甲醇 -四氢呋喃 -水 ( 90∶ 4∶ 6,0 .2 %三乙胺 )为流动相 ,VD3为内标物 ,在 2 30 nm波长处检测。结果 :黄芪甲苷在 0 .0 0 4～ 0 .0 80mg· m L-1范围内呈线性 ,相关系数为 0 .9999,平均回收率为 94 .7%。用该法对不同产地、不同品种的黄芪中黄芪甲苷进行测定 ,结果含量差异较大。结论 :该法准确 ,灵敏度高 ,重现性好 ,为中药黄芪质量评价提供了现代化的科学依据。

关键词：黄芪黄芪甲苷中药柱前衍生化 HPLC 含量测定

Dynamic event-triggered data-driven iterative learning bipartite tracking control for nonlinear MASs with prescribed performance

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Science China(Information Sciences) 2025年第1期68卷 292-305页

作者： Tao SHI Wei-Wei che School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Information Science and Engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

关键词： bipartite tracking control prescribed performance event-triggered iterative learning control multiagent systems

Spontaneous Orientation Polarization of Anisotropic Equivalent Dipoles Harnessed by Entropy Engineering for Ultra‑Thin Electromagnetic Wave Absorber

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Nano-Micro Letters 2025年第1期17卷 424-438页

作者： Honghan Wang Xinyu Xiao Shangru Zhai Chuang Xue Guangping Zheng Deqing Zhang Renchao che Junye cheng Liaoning Key Lab of Lignocellulose chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefinerySchool of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034People’s Republic of China School of Life Science and Biotechnology Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Department of Materials Science Shenzhen MSU-BIT UniversityShenzhen 517182People’s Republic of China

The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric *** migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent ***,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent *** virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 *** mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).

关键词： High-entropy alloys Carbothermal shock Switchable electron migration modes Emblematic shell-core heterointerfaces Ultra-thin thickness

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang Yuan Liting Yang Guisheng Liang Yifeng cheng Limin Wu Chunfu Lin Renchao che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo Feng Chongbo Liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao che Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

The shifts of precipitation phases and their impacts

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Science China Earth Sciences 2025年

作者： Xuemei LI Tao che Yuanlong TANG Huan'e DUAN Guigang WANG Xu ZHANG Chuanming YANG Jun WU Yue ZHANG Lanhai LI Faculty of Geomatics Lanzhou Jiaotong University National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Key Laboratory of Science and Technology in Surveying & Mapping Gansu Province Key Laboratory of Cryospheric Science and Frozen Soil Engineering Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Xinjiang Institute of Ecology and Geography Chinese academy of Sciences Tianshan Snow Cover and Avalanche Observation and Research Station of Xinjiang

Precipitation comes in various phases, including rainfall, snowfall, sleet, and hail. Shifts of precipitation phases, as well as changes in precipitation amount, intensity, and frequency, have significant impacts on regional climate, hydrology,ecology, and the energy balance of the land-atmosphere system. Over the past century, certain progress has been achieved in aspects such as the observation, discrimination, transformation, and impact of precipitation phases. Mainly including:since the1980s, studies on the observation, formation mechanism, and prediction of precipitation phases have gradually received greater attention and reached a certain scale. The estimation of different precipitation phases using new detection theories and methods has become a research focus. Avariety of discrimination methods or schemes, such as the potential thickness threshold method of the air layer, the temperature threshold method of the characteristic layer, and the near-surface air temperature threshold method,have emerged one after another. Meanwhile, comparative studies on the discrimination accuracy and applicability assessment of multiple methods or schemes have also been carried out simultaneously. In recent years, the shift of precipitation from solid to liquid (SPSL) in the mid-to-high latitudes of the Northern Hemisphere has become more pronounced due to global warming and human activities. It leads to an increase in rain-on-snow (ROS) events and avalanche disasters, affecting the speed, intensity, and duration of spring snow-melting, accelerating sea ice and glacier melting, releasing carbon from permafrost, altering soil moisture, productivity, and phenological characteristics of ecosystems, and thereby affecting their structures, processes, qualities, and service functions. Although some progress has been made in the study of precipitation phases, there remains considerable research potential in terms of completeness of basic data, reliability of discrimination schemes,

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压应力激活SOST/Wnt/β-catenin 通路诱导软骨终板细胞退变

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中国组织工程研究 2025年第5期29卷 951-957页

作者：项攀车艳军罗宗平苏州大学附属第一医院骨科研究所江苏省苏州市215006 南京医科大学附属苏州医院骨科与运动医学中心江苏省苏州市215000

背景:在许多可以导致椎间盘退变的因素中(衰老、营养匮乏、机械因素等),力学负荷被认为是极其重要的因素,但其机制尚不清楚。目的:探讨硬骨素和Wnt/β-catenin信号通路在压应力诱导终板软骨退变中的作用。方法:提取4周龄雄性SD大鼠软骨... 详细信息

背景:在许多可以导致椎间盘退变的因素中(衰老、营养匮乏、机械因素等),力学负荷被认为是极其重要的因素,但其机制尚不清楚。目的:探讨硬骨素和Wnt/β-catenin信号通路在压应力诱导终板软骨退变中的作用。方法:提取4周龄雄性SD大鼠软骨终板细胞,体外利用力学加载仪器对终板软骨细胞施加压应力,于压缩细胞1,3,5,7 d,采用CCK-8法测定细胞活力;Western blot、RT-qPCR及细胞免疫荧光等检查终板软骨细胞内软骨标记物(聚集蛋白聚糖、Ⅱ型胶原)、钙化相关因子(Runx2、骨钙素)、细胞外基质降解酶及信号通路基因(硬骨素、β-catenin)等表达。结果与结论:①压应力作用下,终板软骨细胞活力会随着压应力时间、强度增加而降低;②终板软骨细胞的软骨标记物(聚集蛋白聚糖、Ⅱ型胶原)表达下降,而钙化相关因子(Runx2、骨钙素)表达上升;③压应力能促进终板软骨细胞的细胞外基质降解,基质金属蛋白酶3、基质金属蛋白酶13表达量增加;④细胞内Wnt/β-catenin信号通路表达出现异常,其特异性抑制因子硬骨素伴随着β-catenin的异常积累而表达下降。结果说明:在压应力作用下,终板软骨细胞内硬骨素的表达下降,导致Wnt/β-catenin信号通路激活,促进软骨终板的钙化、退变与细胞外基质的降解,进而促进椎间盘退变。

关键词：软骨终板软骨细胞 SOST Wnt/β-catenin 压应力椎间盘退变

Combating with extremely noisy samples in weakly supervised slot filling for automatic diagnosis

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Frontiers of Computer Science 2023年第5期17卷 67-73页

作者： Xiaoming SHI Wanxiang che School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China

Slot filling,to extract entities for specific types of information(slot),is a vitally important modular of dialogue systems for automatic *** responses can be regarded as the weak supervision of patient *** this way,a large amount of weakly labeled data can be obtained from unlabeled diagnosis dialogue,alleviating the problem of costly and time-consuming data ***,weakly labeled data suffers from extremely noisy *** alleviate the problem,we propose a simple and effective Co-WeakTeaching *** method trains two slot filling models *** two models learn from two different weakly labeled data,ensuring learning from two ***,one model utilizes selected weakly labeled data generated by the other,*** model,obtained by the Co-WeakTeaching on weakly labeled data,can be directly tested on testing data or sequentially fine-tuned on a small amount of human-annotated *** results on these two settings illustrate the effectiveness of the method with an increase of 8.03%and 14.74%in micro and macro f1 scores,respectively.

关键词： dialogue system slot filling co-teaching