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In Situ Analysis of Tobacco Leaves Based on Microwave Plasma Torch Desorption Ionization Mass Spectrometry

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Journal of Analysis and Testing 2024年第1期8卷 9-15页

作者： He Tang Yonggang Zhang Zhiguang Reng Junchen Zhu Yue xie Xiaobin Zhang Hongru Feng Kailong yuan yuanjiang Pan Department of Chemistry Zhejiang UniversityHangzhou 310027China Zhejiang China Tobacco Industrial Co. Ltd.Hangzhou310008China

Tobacco is an important economic crop *** leaves contain a large number of natural ***,the analysis of tobacco composition is crucial for the control of tobacco safety and quality *** plasma torch desorption ionization mass spectrometry(MPT-MS) is an emerging ambient mass spectrometry(AMS) technique that can be used for rapid real-time analysis of s amples without *** work focuses on the chemical composition analysis of tobacco using MPT-MS,and 14 compounds were detected in green flue-cured tobacco leaves,while 30 compounds were detected in cured flue-cured tobacco leaves,which confirms that curing can enhance the flavor of ***,we successfully in situ identified characteristic fragment ions of α/β-CBD(α/β-cembranoids),an important aroma compound in tobacco by *** results demonstrate the capability of MPT-MS for in situ analysis of tobacco components and its potential for evaluating tobacco quality.

关键词： Microwave plasma torch Ambient mass spectrometry Tobacco α/β-Cembranoids

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： mei Chen Sheng-He Wu Rui-Feng Wang Jia-Jia Zhang Peng-Fei xie Min Wang Xiao-Feng Wang Ji-Tao Yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of Geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of Geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine ***,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine *** this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East *** characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic *** find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single *** the topography is irregular and presents topographic lows,lobe complexes first infill these *** lobes are deposited preferentially at positions with higher longitudinal(***-slope)slope *** the longitudinal slope becomes higher,the aspect ratio of the single lobes ***(***-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single *** the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap ***,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,*** tend to accumulate *** results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean

Optical modification of nonlinear crystals for quasi-parametric chirped-pulse amplification

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Fundamental Research 2024年第1期4卷 43-50页

作者： Qian Lin Jingui Ma Zhe Yin Peng yuan Jing Wang Guoqiang xie Liejia Qian Key Laboratory for Laser Plasmas(MOE) Collaborative Innovation Center of IFSASchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

Quasi-parametric chirped-pulse amplification(QPCPA),which features a theoretical peak power much higher than those obtained with Ti:sapphire laser or optical parametric chirped-pulse amplification,is promising for future ultra-intense *** doped rare-earth ion used for idler dissipation is critical for effective QPCPA,but is usually not compatible with traditional *** far,only one dissipative crystal of Sm^(3+)-doped yttrium calcium oxyborate has been grown and *** we introduce optical means to modify traditional crystals for QPCPA *** theoretically demonstrate two dissipation schemes by idler frequency doubling and sum-frequency generation with an additional *** contrast to absorption dissipation,the proposed nonlinear dissipations ensure not only high signal efficiency but also high small-signal *** demonstrated ability to optically modify crystals will facilitate the wide application of QPCPA.

关键词： Quasi-parametric amplifier Second-harmonic generation Sum-frequency generation Back conversion Idler dissipation

Design,synthesis and biological evaluation of fluorescent derivatives of ursolic acid in living cells

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Chinese Chemical Letters 2024年第5期35卷 287-289页

作者： Wenyi mei Lijuan xie Xiaodong Zhang Cunjian Shi Fengzhi Wang Qiqi Fu Zhenjiang Zhao Honglin Li Yufang Xu Zhuo Chen Shanghai Key Laboratory of New Drug Design State Key Laboratory of Bioreactor EngineeringSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China Innovation Center for AI and Drug Discovery East China Normal UniversityShanghai 200062China Lingang Laboratory Shanghai 200031China

Ursolic acid(UA)is a naturally occurring ursane triterpenoid,which exhibits a wide range of unique biological *** clarify its mechanism of action(MOA),a series of fluorescent derivatives of UA(5a-c)were designed and synthesized by conjugation with 7-nitrobenzo-2-oxa-1,3-diazole(NBD)*** them,5c exhibited similar anti-proliferative activity with UA against HCT116 cells(half maximal inhibitory concentration(IC_(50))=9.21±0.50μmol/L).Cell imaging experiment indicated that 5c was rapidly taken up in HCT116 cells in a dose and time-dependent ***,5c was found to localize in endoplasmic reticulum(ER),lysosomes,and mitochondria,but not in nucleus of HCT116 cells by confocal microscopy *** MOA proved that UA induced autophagy with a unique intracellular distribution mechanism involving ER and *** all,our work provides new clues for revealing the molecular mechanism of UA as an antitumor agent.

关键词： Pentacyclic triterpenoid Ursolic acid Fluorescent derivatives Autophagy Apoptosis

High glucose promotes macrophage M1 polarization through miR-32/Mef2d/cAMP signaling pathway

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Genes & Diseases 2024年第2期11卷 539-541页

作者： Cong Chen Jingsong Cao Yan Gao Xiaoping xie Zhibo Zhao Qing yuan Yuqi He Xuyu Zu Jianghua Liu The First Affiliated Hospital Institute of Endocrinology and MetabolismCenter for Clinical Research in DiabetesHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China The First Affiliated Hospital Department of Laboratory MedicineHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China The First Affiliated Hospital Institute of OncologyHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

Chronic inflammation is a crucial inducerof diabetesvascular *** is that high glucose easily induces macrophage activation.1 Macrophages are the principal participants in innate immunity and exist in all human *** pathological vascular,infiltrated macrophages secrete inflammatory factors leading to an increase in plaque stability.?In macrophage polarization,autophagy plays an important *** of macrophage autophagy could induce macrophage polarization from the M1 phenotype to M2 phenotype and inhibit inflammatory reactions.3 Our previous research found that high glucose condition promotes miR-32 expression and macrophage M1 polarization,4 but the mechanism of miR-32 promoting macrophage M1 polarization is *** this study,we found that,under a high-glucose condition,miR-32/Mef2d/cAMP signaling promoted M1 macrophage polarization via inhibited *** results provide a theoretical and experimental basis for the prevention and treatment of T2D vascular inflammation.

关键词： macrophage miR prevention

A Sampling-Based Method to Estimate the Volume of Solution Space for Linear Arithmetic Constraints

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Journal of Systems Science & Complexity 2024年

作者： xie Yan-Feng yuan Chun-Ming JING Rui-Juan KLMM Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences School of Mathematical Sciences Jiangsu University

The linear arithmetic constraints play important roles in many research fields. Estimating the volume of their solution spaces has specific applications, such as programming verification, linear programming, polyhedral optimization, and so on. In this paper, the authors provide an efficient estimation for the volume of the solution space for linear arithmetic constraints. This method sums up the estimations for volumes of oblique cones centered along randomly generated rays. The error analysis is provided to improve the accuracy.

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Pretreatment and analysis techniques development of TKIs in biological samples for pharmacokinetic studies and therapeutic drug monitoring

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Journal of Pharmaceutical Analysis 2024年第4期14卷 439-459页

作者： Lan Chen yuan Zhang Yi-Xin Zhang Wei-Lai Wang De-mei Sun Peng-Yun Li Xue-Song Feng Yue Tan School of Pharmacy China Medical UniversityShenyang110122China Institute of Pharmacology and Toxicology Institution National Engineering Research Center for Strategic DrugsBeijing100850China Department of Gastroenterology Shengjing Hospital of China Medical UniversityShenyang110022China

Tyrosine kinase inhibitors(TKIs)have emerged as the first-line small molecule drugs in many cancer therapies,exerting their effects by impeding aberrant cell growth and proliferation through the modulation of tyrosine kinase-mediated signaling ***,there exists a substantial inter-individual variability in the concentrations of certain TKIs and their metabolites,which may render patients with compromised immune function susceptible to diverse infections despite receiving theoretically efficacious anticancer treatments,alongside other potential side effects or adverse ***,an urgent need exists for an up-to-date review concerning the biological matrices relevant to bioanalysis and the sampling methods,clinical pharmacokinetics,and therapeutic drug monitoring of different *** paper provides a comprehensive overview of the advancements in pretreatment methods,such as protein precipitation(PPT),liquid-liquid extraction(LLE),solid-phase extraction(SPE),micro-SPE(μ-SPE),magnetic SPE(MSPE),and vortex-assisted dispersive SPE(VA-DSPE)achieved since *** also highlights the latest analysis techniques such as newly developed high performance liquid chromatography(HPLC)and high-resolution mass spectrometry(HRMS)methods,capillary electrophoresis(CE),gas chromatography(GC),supercritical fluid chromatography(SFC)procedures,surface plasmon resonance(SPR)assays as well as novel nanoprobes-based biosensing *** addition,a comparison is made between the advantages and disadvantages of different approaches while presenting critical challenges and prospects in pharmacokinetic studies and therapeutic drug monitoring.

关键词： TKIs Microextraction technique HRMS methods Pharmacokinetic studies Therapeutic drug monitoring

Antimicrobial Resistance Analysis and Whole-Genome Sequencing of Salmonella Isolates from Environmental Sewage — Guangzhou City, Guangdong Province, China, 2022–2023

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China CDC weekly 2024年第13期6卷 254-260页

作者： Bihui Su Guanghong Du Shuiping Hou Zongqiu Chen Xiaoying Wu Gang He Jun yuan Chaojun xie Tuberculosis Management and Treatment Department Guangzhou Chest HospitalGuangzhou CityGuangdong ProvinceChina School of Public Health Guangzhou Medical UniversityGuangzhou CityGuangdong ProvinceChina Guangzhou Center for Disease Control and Prevention Guangzhou CityGuangdong ProvinceChina Office of the Director Huadu District Center for Disease Control and PreventionGuangzhou CityGuangdong ProvinceChina

What is already known about this topic?S.1,4,[5],12:i:-and *** are emerging serotypes of Salmonella that require close monitoring for antimicrobial resistance and containment of their *** is added by this report?The study aimed to identify antimicrobial resistance genes(ARGs)in S.1,4,[5],12:i:-and *** strains isolated from environmental sewage in Guangzhou City,Guangdong Province,China.A phylogenetic tree was constructed using single nucleotide polymorphism data to assess genetic relatedness among strains,offering insights for Salmonella infection outbreak investigations in the *** are the implications for public health practice?It is crucial to implement strategies,such as integrating different networks,to control the spread of drugresistant *** technologies must be utilized to disinfect sewage and eliminate *** food safety and proper sewage disinfection are essential to curb the dissemination of Salmonella.

关键词： Whole offering integrating

A seven-crystal spectrometer for high-energy resolution X-ray spectroscopy at Shanghai Synchrotron Radiation Facility

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Nuclear Science and Techniques 2024年第9期35卷 82-91页

作者： Bing-Bao mei Liang-Xin Wang Song-Qi Gu Xiao-Zhi Su Shuo Zhang Yao Wei Jing-yuan Ma Zheng Jiang Fei Song Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray *** spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction *** under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical *** offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy ***,they provide substantial support for scientific advances in fundamental research.

关键词： X-ray emission spectroscopy High-energy-resolution X-ray spectrometer Johann geometry Energy materials SSRF