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Acta Pharmaceutica Sinica B 2024年第6期14卷 2657-2668页

作者： Chenxu Zhao Jingrong li yue hu lingyu li Meng Yu Yunfeng huang Tao Zhang Hai Shang Zhongmei Zou State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China Institute of Chinese Medicine Resources Guangxi Institute of Chinese Medicine&Pharmaceutical ScienceNanning 530000China

A pair of coumarin-based polycyclic meroterpenoid enantiomers(+)/(-)-gerbeloid A[(+)-1a and(-)-1b]were isolated from the medicinal plant Gerbera piloselloides,which have a unique caged oxatricyclo[4.***.2.0^(3,8)]decene *** planar and three-dimensional structures were exhaustively characterized by comprehensive spectroscopic data and X-ray diffraction *** by the hypothetical biosynthetic pathway,the biomimetic synthesis of racemic 1 was achieved using 4-hydroxy-5-methylcoumarin and citral as the starting material via oxa-6πelectrocyclization and intramolecular[2+2]***,the results of the biological activity assay demonstrated that both(+)-1a and(-)-1b exhibited potent lipid-lowering effects in 3T3-L1 adipocytes and the high-fat diet zebrafish ***,the lipid-lowering activity of(+)-1a is better than that of(-)-1b at the same concentration,and molecular mechanism study has shown that(+)-1a and(-)-1b impairs adipocyte differentiation and stimulate lipolysis by regulating C/EBPα/PPARγsignaling and Perilipin signaling in vitro and in *** findings provide a promising drug model molecule for the treatment of obesity.

关键词： Gerbera piloselloides Natural products Coumarin meroterpenoid Structural elucidation Biomimetic synthesis lipid-lowering activity 3T3-L1 adipocytes High-fat diet zebrafish model

Drought weakens the positive effect of plant diversity on community biomass

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Journal of Plant Ecology 2024年第4期17卷 141-153页

作者： Yanhui Hou Xiaona li Yanxia hu Xuwei Lu yue Ma Wenmin li Xiran Lü Zimo li Yaxuan Bai Chao Wang Institute of Grassland Flowers and EcologyBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China College of Grassland Science Shanxi Agricultural UniversityJinzhong 030801China College of Landscape Architecture and Art Henan Agricultural UniversityZhengzhou 450002China College of Agriculture and Forestry Hebei North UniversityZhangjiakou 075000China

Drought can greatly impact the biodiversity of an ecosystem and play a crucial role in regulating its ***,the specific mechanisms by which drought mediate the biodiversity effect(BE)on community biomass in above-and belowground through functional traits remain poorly ***,we conducted a common garden experiment in a greenhouse,which included two plant species richness levels and two water addition levels,to analyze the effects of biodiversity on aboveground biomass(AGB),belowground biomass(BGB)and total biomass(TB),and to quantify the relationship between BEs and functional traits under drought *** analysis focused on partitioning BEs into above-and belowground complementarity effect(CE)and selection effect(SE)at the species level,which allowed us to better understand the impacts of biodiversity on community biomass and the underlying *** results showed that plant species richness stimulated AGB,BGB and TB through *** decreased AGB,BGB and TB,*** addition,the aboveground CE was positively associated with the variation in plant *** in above-and belowground were negatively correlated with the community mean plant height and root length,***,drought weakened the aboveground CE by decreasing variation in plant height,resulting in a reduction in AGB and *** findings demonstrate that the complementarity of species is an important regulator of community biomass in above-and belowground,the dynamics of biomass under environmental stress are associated with the response of sensitive compartments.

关键词： biodiversity effect drought plant height root length aboveground biomass belowground biomass

An upgraded Myxococcus xanthus chassis with enhanced growth characteristics for efficient genetic manipulation

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Engineering Microbiology 2024年第3期4卷 62-66页

作者： Weifeng hu Yan Wang Xiaoran yue Weiwei Xue Wei hu Xinjing yue yuezhong li State Key Laboratory of Microbial Technology Institute of Microbial TechnologyShandong UniversityQingdao 266237China

Myxobacteria are well known for multicellular social behaviors and valued for biosynthesis of natural *** social behaviors such as clumping growth severely hamper strain cultivation and genetic *** Myxococcus xanthus DK1622,we engineered hu04,which is deficient in multicellular behavior and ***04,while maintaining nutritional growth and a similar metabolic background,exhibits improved dispersed growth,streamlining operational *** achieves high cell densities in culture and is promising for synthetic biology applications.

关键词： Myxococcus xanthus Operation deficiency Phenotypic optimization Chassis Genetic performance

Operando measurement of lattice deformation profiles of synchrotron radiation monochromator

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Nuclear Science and Techniques 2024年第7期35卷 8-19页

作者： yue Zhang Zhong-liang li Shang-Yu Si lian Xue Hong-Xin Luo Xiao-Wei Zhang Jun hu Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201204China ShanghaiTech University Shanghai201210China University of the Chinese Academy of Sciences Beijing100049China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing100049China

This study presents a new method for characterizing the thermal lattice deformation of a monochromator with high precision under service conditions and first reports the operando measurements of nanoscale thermal lattice deformation on a double-crystal monochromator at different incident *** nanoscale thermal lattice deformation of the monochromator first crystal was obtained by analyzing the intensity of the distorted DuMond *** diagrams of the 333 diffraction index,sensitive to lattice deformation,were obtained directly using a 2D detector and an analyzer crystal orthogonal to the *** increasing incident power and power density,the maximum height of the lattice deformation increased from 3.2 to 18.5 nm,and the deformation coefficient of the maximum height increased from 1.1 to 3.2 nm/*** maximum relative standard deviation was 4.2%,and the maximum standard deviation was 0.1 *** on the measured thermal deformations,the flux saturation phenomenon and critical point for the linear operation of the monochromator were predicted with increasing incident *** study provides a simple solution to the problem of the lower precision of synchrotron radiation monochromator characterizations compared to simulations.

关键词： Synchrotron radiation Monochromator Lattice deformation X-ray dynamic diffraction

A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： Meng li hu DING Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping *** this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first *** motion differential equations of the VTNES coupled with a linear oscillator(LO)are *** the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified *** this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is *** damping effect and dynamic characteristics of the VTNES are studied theoretically and *** results show that the VTNES has better damping effects when strong modulation responses(SMRs)***,even for small-amplitude vibration,the VTNES also has a good vibration suppression *** sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

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Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian li Zi-Jie lin liu Yang yue Wang yue li Wei-hua Cai Laboratory of Thermo-Fluid Science and Nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and Power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

Superior compound coatings prepared by low-temperature vanadium-nitrocarburizing duplex treatment

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Rare Metals 2024年第4期43卷 1828-1835页

作者： Gen Jin Fang-Fang Xu Xun-Xun hu yue Xu School of Chemistry Beihang UniversityBeijing100191China Guobiao(Beijing)Testing and Certification Co. LtdBeijing100088China School of Materials Science and Engineering Beihang UniversityBeijing100191China

Superior compound coatings were prepared on CK45 steel surface by vanadium-nitrocarburizing duplex treatment in low-temperature salt *** this study,the microhardness,the phase constitution and the compositional distribution in the coatings prepared under different conditions were systematically *** results indicated that the reactions among activated vanadium,carbon and nitrogen atoms occurred on the steel surface,leading to the formation of compound coatings composed of outermost and compound *** mechanism for the formation of compound layer as well as the growth kinetics of the layer was also *** the duplex treatment,the wear and corrosion resistances of steel surface were significantly *** was found that the growth kinetics of compound layer obeyed the parabolic law,with the activation energy of 122.82 kJ·moL^(-1).

关键词： Vanadium-nitrocarburizing duplex treatment Compound coatings Microstructure Formation mechanism Growth kinetics

Perspective on powder technology for all-solid-state batteries:How to pair sulfide electrolyte with high-voltage cathode

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Particuology 2024年第3期86卷 55-66页

作者： Jiangkui hu Shijie Yang Yingying Pei Xilong Wang Yulong liao Shuai li Aolong yue Jia-Qi huang Hong Yuan School of Materials Science&Engineering Beijing Institute of TechnologyBeijing100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing100081China

Sulfide solid electrolytes(SEs)have attracted ever-increasing attention due to their superior roomtemperature ionic conductivity(~10^(-2) S cm^(-1)).Additionally,the integration of sulfide SEs and highvoltage cathodes is promising to achieve higher energy ***,the incompatible interfaces between sulfide SEs and high-voltage cathodes have been one of the key factors limiting their ***,this review presents a critical summarization of the interfacial issues in all-solid-state lithium batteries based on sulfide SEs and high-voltage cathodes and proposes strategies to stabilize the electrolyte/cathode ***,the future research direction of electrolyte/cathode interfaces and application prospects of powder technology in sulfide-based ASSLBs were also discussed.

关键词： Sulfide solid electrolytes High-voltage cathodes Electrode/electrolyte interfaces All-solid-state lithium batteries

EPR-Net: constructing a non-equilibrium potential landscape via a variational force projection formulation

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National Science Review 2024年第7期11卷 135-147页

作者： yue Zhao Wei Zhang Tiejun li Center for Data Science Peking University Zuse Institute Berlin Department of Mathematics and Computer Science Freie Universit?t Berlin Laboratory of Mathematics and Applied Mathematics(LMAM)and School of Mathematical Sciences Peking University Center for Machine Learning Research Peking University

We present EPR-Net, a novel and effective deep learning approach that tackles a crucial challenge in biophysics: constructing potential landscapes for high-dimensional non-equilibrium steady-state ***-Net leverages a nice mathematical fact that the desired negative potential gradient is simply the orthogonal projection of the driving force of the underlying dynamics in a weighted inner-product ***, our loss function has an intimate connection with the steady entropy production rate(EPR),enabling simultaneous landscape construction and EPR estimation. We introduce an enhanced learning strategy for systems with small noise, and extend our framework to include dimensionality reduction and the state-dependent diffusion coefficient case in a unified fashion. Comparative evaluations on benchmark problems demonstrate the superior accuracy, effectiveness and robustness of EPR-Net compared to existing methods. We apply our approach to challenging biophysical problems, such as an eight-dimensional(8D)limit cycle and a 52D multi-stability problem, which provide accurate solutions and interesting insights on constructed landscapes. With its versatility and power, EPR-Net offers a promising solution for diverse landscape construction problems in biophysics.

关键词： high-dimensional potential landscape non-equilibrium system entropy production rate dimensionality reduction deep learning

Method for the navigation line recognition of the ridge without crops via machine vision

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 230-239页

作者： Wei liu Jianping hu Jiaxin liu Rencai yue Tengfei Zhang Mengjiao Yao Jing li School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Some agriculture machinery like the transplanter,needs to operate by following the crop-free *** order to improve working efficiency and quality,some autonomous navigation systems were developed and applied to ridge-following *** present,agricultural navigation systems are mainly the satellite navigation system and the machine vision *** satellite navigation system is difficult to apply to the machinery that needs to work by following the ridge because it cannot distinguish the shape of the navigated ridge and guide the machinery working along the *** this study,697 cloudy ridge images and 235 sunny ridge images were taken in the field,and these images were used as the ***,a machine vision navigation method based on the color of ridges was ***,the regions of interest(ROI)in the ridge image were extracted according to the reaction time and the forward speed of the ***,a gray reconstruction method was used to enlarge the color difference between the ridge and the *** optimal threshold for the gray image segmenting was calculated real-timely by using the threshold segmentation ***,based on the contour detection method,the ridge contour which was not surrounded by holes was ***,the approximate quadrilateral method was proposed to recognize the ridge center line as the navigation *** method proposed in this study was verified by four types of ridges with different colors and *** experimental results showed that the recognition success rates of the light ridge,the dark ridge,the film-covered ridge,and the sunny ridge were 100%,97.5%,100%,and 98.7%,*** recognition success rate of the proposed method was at least 8%higher than that of the existing ridge-furrow recognition *** results indicate that this method can effectively realize navigation line *** method can provide technical support for the autonomous navigation of agricultural mac

关键词： navigation line recognition machine vision ridge line recognition intelligent agriculture