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Three rare anti-inflammatory sesquiterpene lactones from Magnolia grandiflora

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Chinese Journal of Natural Medicines 2024年第3期22卷 265-272页

作者： XU Shuangyu ZHANG Feng TAO Linlan JIANG Yangming HUANG Tao LI Yanan HU Zhanxing YANG Jue HAO Xiaojiang YUAN Chunmao State Key Laboratory of Functions and applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China School of Pharmaceutical sciences Guizhou Medical UniversityGuiyang 550025China Natural Products Research center of Guizhou Province Guiyang 550014China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Four new sesquiterpene lactones(SLs)(1–4),along with a biosynthetically related SL(5),have been isolated from the leaves of Magnolia *** A(1)is notable as the first C18 homogemarane type SL,featuring a unique 1,7-dioxaspiro[4.4]nonan-6-one *** 2 and 3,representing the first instances of chlorine-substituted gemarane-type SL analogs in natural products,were also *** structures of these isolates were elucidated through a combination of spectroscopic data analysis,electronic circular dichroism calculations,and X-ray single-crystal diffraction *** isolates demonstrated anti-inflammatory activity in lipopolysaccharide-stimulated RAW264.7 ***,3–5 showed a significant inhibitory effect on nitric oxide production,with IC50 values ranging from 0.79 to 4.73μmol·L^(−1).Additionally,4 and 5 exhibited moderate cytotoxic activities against three cancer cell lines,with IC50 values between 3.09 and 11.23μmol·L^(−1).

关键词： Magnolia grandiflora Sesquiterpene lactones Isolation and identification Anti-inflammatory activity

Unusual photocarrier and coherent phonon dynamics behaviors of layered PdSe_(2)unveiled by ultrafast spectroscopy of the edge surface

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 143-152页

作者： Tiantian Yun Changfu Huo Jinluo Cheng Zhi-Bo Liu Xiao-Qing Yan Key Laboratory of Weak-Light Nonlinear Photonics Ministry of EducationSchool of PhysicsNankai UniversityTianjin 300071China Collaborative Innovation center of Extreme Optics Shanxi UniversityTaiyuan 030006China GPL Photonics Laboratory Key Laboratory of Luminescence Science and TechnologyChinese Academy of Sciences&State Key Laboratory of Luminescence Science and ApplicationsChangchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Layered materials exhibit different electronic and phonon properties along in-plane and out-of-plane directions;existing studies focus on their in-plane behaviors,and the influence of such anisotropies on the dynamics of photocarriers and phonons is ***,we fabricate layered PdSe_(2)crystals with flat edge surfaces and compare the time-resolved ultrafast spectroscopies on their basal and edge *** differences in the transient reflection spectroscopies reveal the inconsistent photocarrier and phonon dynamics behaviors on the two surfaces:the slow hot carrier relaxation process is accelerated and the thermoelasticity-induced longitudinal coherent acoustic phonon oscillation completely vanishes on the edge surface,as compared with the basal *** analysis reveals that the inconsistent hot carrier dynamics originate from the anisotropic properties of low-energy phonons in PdSe_(2),and the absence of phonon oscillation on the edge surface results from the wavevector-limited sensitivity of acoustic B_(1u)***,polarization-dependent spectroscopies indicate the diverse optical anisotropies beyond the in-plane of PdSe_(2).This work provides a new method to explore unique physical properties and modulate the optical anisotropy of layered materials.

关键词： PdSe_(2) ultrafast spectroscopy edge surface carrier dynamics coherent phonon oscillation anisotropy

Circular polarization-selective optical,photothermal,and optofluidic effects in chiral metasurfaces

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Photonics Research 2024年第2期12卷 331-340页

作者： CUIPING MA PENG YU ZHIMIN JING YISONG ZHU PEIHANG LI WENHAO WANG HONGXING XU YANNING ZHANG LIANG PAN TAE-YOUL CHOI ARUP NEOGI ALEXANDER OGOVOROV ZHIMING WANG Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 610054China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore School of Physics and Technology Center for Nanoscience and NanotechnologyWuhan UniversityWuhan 430072China Department of Mechanical Engineering University of North TexasDentonTexas 76207USA Department of Physics and Astronomy and Nanoscale and Quantum Phenomena Institute Ohio UniversityAthensOhio 45701USA

Circular dichroism (CD) is extensively used in various material systems for applications including biological detection,enantioselective catalysis,and chiral *** paper introduces a chiral absorptive metasurface that exhibits a circular polarization-selective effect in dual bands-positive and negative CD peaks at short wavelengths and long wavelengths,***,we uncover that this phenomenon extends beyond the far-field optical response,as it is also observed in the photothermal effect and the dynamics of thermally induced fluid *** carefully engineering the metasurface design,we achieve two distinct CD signals with high g factors (1) at the wavelengths of 877 nm and 1045 nm,*** findings presented in this study advance our comprehension of CD and offer promising prospects for enhancing chiral light–matter interactions in the domains of nanophotonics and optofluidics.

关键词： chiral catalysis circular

A new class of generalized quasi-variational inequalities with applications to Oseen problems under nonsmooth boundary conditions

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Science China Mathematics 2024年第2期67卷 315-338页

作者： Shengda Zeng Akhtar A.Khan Stanislaw Migórski Guangxi Colleges and Universities Key Laboratory of Complex System Optimization and Big Data Processing Yulin Normal UniversityYulin 537000China Faculty of Mathematics and Computer Science Jagiellonian University in Krak´owKrak´ow 30348Poland center for Applied and Computational Mathematics School of Mathematical SciencesRochester Institute of TechnologyRochesterNY 14623USA College of sciences Beibu Gulf UniversityQinzhou 535000China

In this paper, we study a generalized quasi-variational inequality (GQVI for short) with twomultivalued operators and two bifunctions in a Banach space setting. A coupling of the Tychonov fixedpoint principle and the Katutani-Ky Fan theorem for multivalued maps is employed to prove a new existencetheorem for the GQVI. We also study a nonlinear optimal control problem driven by the GQVI and givesufficient conditions ensuring the existence of an optimal control. Finally, we illustrate the applicability of thetheoretical results in the study of a complicated Oseen problem for non-Newtonian fluids with a nonmonotone andmultivalued slip boundary condition (i.e., a generalized friction constitutive law), a generalized leak boundarycondition, a unilateral contact condition of Signorini’s type and an implicit obstacle effect, in which themultivalued slip boundary condition is described by the generalized Clarke subgradient, and the leak boundarycondition is formulated by the convex subdifferential operator for a convex superpotential.

关键词： generalized quasi-variational inequality existence theorem optimal control Kakutani-Ky Fan theorem Oseen problem non-Newtonian fluid nonmonotone slip boundary condition

A survey on federated learning:a perspective from multi-party computation

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Frontiers of Computer Science 2024年第1期18卷 93-103页

作者： Fengxia LIU Zhiming ZHENG Yexuan SHI Yongxin TONG Yi ZHANG Institute of Artificial Intelligence and Key Laboratory of Mathematics Informatics Behavioral Semantics Beihang UniversityBeijing 100191China State Key Laboratory of Software Development Environment and Advanced Innovation center for Future Blockchain and Privacy Computing Beihang UniversityBeijing 100191China Pengcheng Laboratory Shenzhen 518055China Zhongguancun Laboratory Beijing 100190China Institute for mathematical sciences and Engineering Research center of Financial Computing and Digital Engineering Renmin University of ChinaBeijing 100872China

Federated learning is a promising learning paradigm that allows collaborative training of models across multiple data owners without sharing their raw *** enhance privacy in federated learning,multi-party computation can be leveraged for secure communication and computation during model *** survey provides a comprehensive review on how to integrate mainstream multi-party computation techniques into diverse federated learning setups for guaranteed privacy,as well as the corresponding optimization techniques to improve model accuracy and training *** also pinpoint future directions to deploy federated learning to a wider range of applications.

关键词： sfederated learning multi-party ycomputation privacy-preserving data mining distributed learning

Phase field modeling of ferroelastic variant switching in yttria-stabilized t'zirconia with strain gradient elasticity and interface tension

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Science China(Technological sciences) 2024年第5期67卷 1443-1457页

作者： ZHOU QianQian WEI YueGuang ZHOU YiChun YANG Li College of Engineering BIC-ESATPeking UniversityBeijing100871China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an710126China Frontier Research center of Thin Films and Coatings for Device applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an710126China

The 6–8 wt%yttria-stabilized zirconia with a tetragonal structure(t’-YSZ)is extensively employed in thermal barrier *** exceptional fracture toughness of t’-YSZ can be attributed to its distinctive ferroelastic toughening *** and interface tension play a critical role in ferroelastic variant switching at the micro-and *** paper presents an original thermodynamically consistent phase field(PF)theory for analyzing ferroelastic variant switching at the micro-and nano-scale of t’-*** theory incorporates strain gradient elasticity using higher-order elastic energy and interface tension tensor via geometric nonlinearity to represent biaxial tension resulting from interface ***,a mixed-type formulation is employed to implement the higher-order theory through the finite element *** an interface in equilibrium,the effects of strain gradient elasticity result in a more uniform distribution of stresses,whereas the presence of interface tension tensor significantly amplifies the stress magnitude at the *** introduction of an interface tension tensor increases the maximum value of stress at the interface by a factor of 4 to *** nucleation and evolution of variants at a pre-existing crack tip in a mono-phase t’-YSZ have also been *** strain gradient elasticity is capable of capturing the size effect of ferroelastic variant switching associated with microstructures in ***,when the grain size approaches that of the specimen,the critical load required for variant switching at the crack tip increases,resulting in greater dissipation of elastic energy during ferroelastic variant ***,the interface tension accelerates the evolution of *** presented framework exhibits significant potential in modeling ferroelastic variant switching at the micro-and nano-scale.

关键词： thermodynamics strain gradient elasticity interface tension phase field method ferroelastic variant switching

Accurate diagnosis of severe coronary stenosis based on resting magnetocardiography: a prospective, single-center, cross-sectional analysis

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Journal of Geriatric Cardiology 2024年第4期21卷 407-420页

作者： Jian-Guo CUI Feng TIAN Yu-Hao MIAO Qin-Hua JIN Ya-Jun SHI Li LI Meng-Jun SHEN Xiao-Ming XIE Shu-Lin ZHANG Yun-Dai CHEN School of Medicine Nankai UniversityTianjinChina Senior Department of Cardiology the Sixth Medical CenterChinese PLA General HospitalBeijingChina Joint Laboratory of Bioimaging Technology and applications SAS-SIM-IT&MEDIShanghaiChina Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghaiChina

OBJECTIVE To evalu ate the role of resting magnetocardiography in identifying seve re coronary artery stenosis in patients with suspected coronary artery *** A total of 513 patients with angina symptoms were included and divided into two groups based on the extent of coronary artery disease determined by angiography:the non-severe coronary stenusis group(<70% stenosis) and the severe coronary stenosis group(≥70% stenosis).The diagnostic model was constructed using magnetic field map(MFM) parameters,either individually or in combination with clinical *** performance of the models was evaluated using receiver operating characteristic curves,accuracy,sensitivity,specificity,positive predictive value(PPV) and ne gative predictive value(NPV).Calibration plots and decision curve analysis were performed to investigate the clinical utility and performance of the models,*** In the severe coronary stenosis group,QR_MCTDd,S_MDp,and TT_(MA)C_(50) were significantly higher than those in the non-severe coronary stenosis group(10,46±10.66 vs,5.11±6.07,P <0.001;7.2±8.64 vs.4.68±6.95,P=0.003;0.32±57.29 vs.0.26±57.29,P <0.001).While,QR_MV_(amp),R_(MA),and T_(MA) in the severe coronary stenosis group were lower(0.23±0.16 vs.0.28±0.16,P<0.001;55.06±48.68 vs.59.24±53.01,P<0.001;51.67±39.32 vs. 60.45±51.33,P <0.001).Seven MFM parameters were integrated into the model,resulting in an area under the curve of 0.810(95% CI:0.765-0.855).The sensitivity,specificity,PPV,NPV,and accurecy were 71.7%,80.4%,93.3%,42.8 %,and 73.5%;*** combined model exhibited an area under the curve of 0.845(95% CI:0.798-0.892).The sensitivity,specificity,PPV,NPV,and accuracy were 84.3%,73.8%,92.6%,54.6%,and 82.1%;*** curves demonstrate d excellent agreement between the nomogram prediction and actual *** decision curve analysis showed that the c ombine d model provided greater net benefit compared to the magnetocardingraphy model.C

关键词： coronary stenosis specificity

Experimental study and numerical modeling of the thermal behavior of an industrial prototype ceramic furnace:Energy and environmental optimization

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Energy and Built Environment 2024年第2期5卷 244-254页

作者： Lahcen BALLI Mohamed HLIMI Youssef ACHENANI Adil ATIFI Bachir HAMRI Engineering sciences and applications Laboratory(LSIA) National School of Applied Sciences(ENSAH)Abdelmalek Essaadi UniversityTetouanMorocco Faculty of sciences and Techniques Moulay Ismaïl UniversityP.O.Box 509-BoutalamineErrachidiaMorocco Engineering and Health sciences and Technologies Research center M2SMENSAMMohammed.V UniversityRabatMorocco Research Team Quality Maintenance Safety QSMMechanical EngineeringDepartment Mohammadia School of EngineersMohammed V UniversityRabatMorocco

This article focuses on the experimental and numerical study of an industrial prototype furnace intended for the production of ceramics in order to improve the energy efficiency and therefore optimize the fuel consumption and the corresponding carbon dioxide *** order to understand the thermal behavior from which stems the energy efficiency of the experimental prototype,we establish in this work,a simplified modeling allowing to establish a mathematical model describing the thermal behavior of the *** model is able to accurately predict the spatial and temporal distribution of the temperature at each point of the furnace to control the firing of the refractory product so that the final product is of good quality in terms of resistance and *** addition,the power consumed by the prototype must be optimized in order to reduce energy and environmental *** particular,this efficient technology has allowed us to save 83% of energy used in the traditional furnace and to reduce 87.36% of the relative carbon dioxide *** simulation of the mathematical model made it possible to compare the numerical results with the experimental measurements obtained by the prototype as well as to validate the model and to adjust the heat transfer parameters.

关键词： Numerical modeling Thermal behavior Ceramic furnace Refractory materials Energy efficiency

Quantum squeezing induced nonreciprocal phonon laser

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 20-30页

作者： Tian-Xiang Lu Yan Wang Keyu Xia Xing Xiao Le-Man Kuang Hui Jing College of Physics and Electronic Information Gannan Normal UniversityGanzhou 341000China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China College of Engineering and Applied sciences National Laboratory of Solid State Microstructuresand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China

Phonon lasers or coherent amplifications of mechanical oscillations are powerful tools for fundamental studies on coherent acoustics and hold potential for diverse applications,ranging from ultrasensitive force sensing to phononic information ***,we propose the use of an optomechanical resonator coupled to a nonlinear optical resonator for directional phonon *** find that by pumping the nonlinear optical resonator,directional optical squeezing can occur along the pump *** a result,we can achieve the directional mechanical gain using directional optical squeezing,thereby leading to nonreciprocal phonon lasing with a well-tunable directional power *** work proposes a feasible way to build nonreciprocal phonon lasers with various nonlinear optical media,which are important for a wide range of applications,such as directional acoustic amplifiers,invisible sound sensing or imaging,and one-way phononic networks.

关键词： nonreciprocal phonon laser directional quantum squeezing optomechanics

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