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Stereodivergent synthesis ofα-fluoroα-azaarylγ-butyrolactones via cooperative copper and iridium catalysis

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Fundamental Research 2024年第1期4卷 77-85页

作者： Kui Tian Xin Chang Lu xiao Xiu-Qin dong Chun-Jiang Wang College of Chemistry and Molecular Sciences Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Suzhou Institute of Wuhan University Suzhou 215123China

The development of stereodivergent synthetic methods to access all four stereoisomers of biologically importantα-fluoroγ-butyrolactones containing vicinal stereocenters is of great importance and poses a formidable challenge owing to ring strain and steric ***,a novel asymmetric[3+2]annulation ofα-fluoroα-azaaryl acetates with vinylethylene carbonate was successfully developed through Cu/Ir-catalyzed cascade allylic alkylation/lactonization,affording a variety of enantioenrichedα-fluoroγ-butyrolactones bearing vicinal stereogenic centers with high reaction efficiency and excellent levels of both stereoselectivity and regioselectivity(up to 98%yield,generally>20:1 dr and>99%ee).Notably,all four stereoisomers of these pharmaceutically valuable molecules could be accessed individually via simple permutations of two enantiomeric *** addition,other azaaryl acetates bearingα-methyl,α-chlorine orα-phenyl group were tolerated well in this *** mechanistic investigations were conducted to explore the process of this bimetallic catalysis based on the results of reaction intermediates,isotopic labelling experiments,and kinetic studies.

关键词： Asymmetric catalysis α-Fluoroγ-butyrolactones Synergistic catalysis Cascade reaction Stereodivergent synthesis

Artemsieverolactones A—H,Eight Guaiane-Type Sesquiterpenoid Trimers from Artemisia sieversiana

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Chinese Journal of Chemistry 2024年第10期42卷 1084-1092页

作者： Wei dong xiao-Yan Huang Tian-Ze Li Yan-Mei Weng Chang-An Geng Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academyof Sciences Beijing 100049China

Eight new guaiane-type sesquiterpenoid trimers,artemsieverolactones A—H,possessing unprecedented scaffolds via biocatalyzed[4+2]Diels−Alder cycloaddition reactions were identified from Artemisia *** structures were determined by comprehensive spectroscopic data,single-crystal X-ray diffraction analyses,and ECD *** terms of structure,artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane-type sesquiterpenoid through four different[4+2]Diels−Alder cycloaddition *** fibrosis assay suggested that five compounds exhibited activity against HSC-LX2 with IC_(50)values ranging from 37.8 to 117.1μmol/*** most active artemsieverolactone B(2)displayed significant inhibitory activity against HSC-LX2 with IC_(50)value of 37.8μmol/L,which was 3 times more active than the positive drug silybin(IC_(50),139.7μmol/L).Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen typeⅠ(ColⅠ),human hyaluronic acid(HA),and human laminin(HL)with IC_(50)values of 40.4μmol/L(Col I),55.1μmol/L(HL),47.3μmol/L(HA),which was 2 to 3-fold more potent than silybin.

关键词： Artemisia sieversiana Artemsieverolactones A-H Guaiane-type sesquiterpenoid trimers Antihepatic fibrosis Extracellular matrix Cancer NMR spectroscopy X-ray diffraction

Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels

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Chinese Physics B 2024年第3期33卷 690-699页

作者：谢笑笑霍良安董雅芳程英英 Business School University of Shanghai for Science and TechnologyShanghai 200093China School of Intelligent Emergency Management University of Shanghai for Science and TechnologyShanghai 200093China School of Management Henan University of Science and TechnologyLuoyang 471023China

While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network *** this study,we construct a new two-layer coupling model to explore the interactions between information and *** upper layer describes the diffusion of disease-related information,and the lower layer represents the disease *** then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the ***,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical *** findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion ***,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease *** study provides valuable insights into policymakers for developing outbreak prevention and control strategies.

关键词： information diffusion disease transmission asymmetric activity levels quarantine strength

Analysis on patents of health care products with substances of medicine food homology in China

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Chinese Herbal Medicines 2024年第3期16卷 412-421页

作者： Haibo Liu Yanfeng Wang Jiali Huang Zhengqi dong Peigen xiao Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China Key Laboratory of Traditional Chinese Medicine Patent Information Resources State Administration of Traditional Chinese MedicineBeijing 100080China Beijing Academy of Science and Technology Beijing 100048China

Objective:The concept of substances of medicine food homology(SMFH)has garnered significant attention in recent *** study conducts a systematic analysis of patent literature related to SMFH,and elucidates the development trends,technical hotspots,and the overall patent protection landscape of SMFH in China over the past two ***:The patent search focused on the SMFH varieties as the objects of inquiry,with retrieval conducted in patent ***,the acquired data underwent processing,analysis,and ***:While the technical threshold for pharmaceutical applications surpasses that of the food service sector,the former may assume a prominent role in the *** and development(R&D)activities in the southeast of China demonstrate robust activity than other *** and scientific research institutions exhibit substantial advantages in patent applications compared with individuals and hold greater potential for future ***:The findings of this patent analysis indicate that China’s SMFH industry are presently undergoing a transition from an extensive model to a high-quality *** quality and technical standards of SMFH products are consistently ***,there is a need for more stringent patent application requirements to align with the evolving development needs.

关键词： patent analysis patent pattern substances of medicine food homology traditional Chinesemedicine

Mechanical Behavior and Failure Mechanism of an As-Extruded Mg-11wt%Y Alloy at Elevated Temperature

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 969-981页

作者： Lan Zhang Dao-Kui Xu Bao-Jie Wang Cui-Lan Lu Shuo Wang Xiang-Bo Xu dong-Liang Wang Xin Lv En-hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangdong510070China

Through carrying out the high-temperature tensile experiments on an as-extruded Mg-11wt%Y alloy at 350℃,400℃,450℃,500℃and 550℃,the mechanical behavior and fracture mechanisms at elevated temperatures are investigated and *** results show that with the increase of temperature,the yield strength and ultimate tensile strength of the alloy increase at first and then decrease,while that the elongation ratio decreases firstly and then *** the sample being tested at 350℃,the values of yield strength,ultimate tensile strength and the elongation ratio are 188 MPa,266 MPa and 11%,*** 400℃,the yield strength and ultimate tensile strength reach the maximum values of,respectively,198 MPa and 277 MPa,but the elongation ratio is the lowest and its value is only 8%.When the applied temperature is increased to 550℃,the values of yield strength and ultimate tensile strength,respectively,decrease to 140 MPa and 192 MPa and the elongation ratio increases to 38%.Failure analysis demonstrates that the fracture surfaces of different samples are mainly composed of plastic dimples and exhibit the typical characteristic of ductile *** observation to the fracture side surfaces indicates that at the temperatures of 350℃and 400℃,microcracks mainly initiate in the interior of Mg_(24)Y_(5)*** the temperatures are 450℃,500℃and 550℃,the cracks preferentially initiate at the Mg_(24)Y_(5)/α-Mg interfaces.

关键词： Mg-Y alloy High-temperature tensile properties Fracture mechanism Failure analysis

Interaction mechanism between BaZrO_(3)/Y_(2)O_(3) refractory and Ti_(2)Ni alloy melts

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Journal of Iron and Steel Research International 2024年第6期31卷 1376-1388页

作者： xiao hou Guang-yao Chen Jian Liu Ming-rui Lv Fei-hai Yu Qi-sheng Feng Rong-bin Li Xiong-gang Lu Chong-he Li State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferromeallurgy and School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Shanghai Special Casting Engineering Technology Research Center Shanghai 201605China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314100ZhejiangChina School of Materials Science and Engineering Shanghai DianJi UniversityShanghai 201306China

The titanium alloys with highly chemical activity require stable crucible refractories that can withstand the erosion of alloy *** phase composition and microstructure are crucial factors that affect the stability of the refractory *** effect of Y_(2)O_(3) on the composition and microstructure of BaZrO_(3) crucible was systematically investigated,and the improved mechanism of the stability of BaZrO_(3)/Y_(2)O_(3) crucible was clarified in comparison with the BaZrO_(3) *** results showed that the erosion layer thickness of the BaZrO_(3)/Y_(2)O_(3) crucible was only 63μm,which was far less than that in the BaZrO_(3) crucible(485μm),and the erosion layer in the BaZrO_(3)/Y_(2)O_(3) crucible also exhibited a higher density than that in the BaZrO_(3) *** the sintering,Y_(2)O_(3) could improve the densification of the BaZrO_(3) crucible due to the solid solution effect between Y_(2)O_(3) and ZrO_(2),which also caused the evaporation of BaO,resulting in the generation of a Y_(2)O_(3)(ZrO_(2))film on the surface of the ***,the Y_(2)O_(3)(ZrO_(2))had higher thermodynamic stability than Y_(2)O_(3),confirming that the BaZrO_(3)/Y_(2)O_(3) crucible with high density exhibited a superior erosion resistance to titanium *** dual-phase structure provides a strategy to design a long-life and stable refractory for melting titanium alloys.

关键词： Barium zirconate Yttrium oxide Dual-phase refractory Titanium alloy Interaction

Integrated multi-omics analysis reveals liver metabolic reprogramming by fish iridovirus and antiviral function of alpha-linolenic acid

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Zoological Research 2024年第3期45卷 520-534页

作者： Lin Liu Ya Zhang Meng-Di Yuan dong-Miao xiao Wei-Hua Xu Qi Zheng Qi-Wei Qin You-Hua Huang xiao-Hong Huang College of Marine Sciences South China Agricultural UniversityGuangdong Laboratory for Lingnan Modern AgricultureGuangzhouGuangdong 510642China Nansha-South China Agricultural University Fishery Research Institute GuangzhouGuangdong 511464China Southern Marine Science and Engineering Guangdong Laboratory ZhuhaiGuangdong 519082China

Iridovirus poses a substantial threat to global aquaculture due to its high mortality rate;however,the molecular mechanisms underpinning its pathogenesis are not well ***,a multi-omics approach was applied to groupers infected with Singapore grouper iridovirus(SGIV),focusing on the roles of key *** showed that SGIV induced obvious histopathological damage and changes in metabolic enzymes within the ***,SGIV significantly reduced the contents of lipid droplets,triglycerides,cholesterol,and *** analysis indicated that the altered metabolites were enriched in 19 pathways,with a notable down-regulation of lipid metabolites such as glycerophosphates and alpha-linolenic acid(ALA),consistent with disturbed lipid homeostasis in the *** of transcriptomic and metabolomic data revealed that the top enriched pathways were related to cell growth and death and nucleotide,carbohydrate,amino acid,and lipid metabolism,supporting the conclusion that SGIV infection induced liver metabolic *** integrative transcriptomic and proteomic analysis indicated that SGIV infection activated crucial molecular events in a phagosome-immune depression-metabolism dysregulation-necrosis signaling *** note,integrative multi-omics analysis demonstrated the consumption of ALA and linoleic acid(LA)metabolites,and the accumulation of L-glutamic acid(GA),accompanied by alterations in immune,inflammation,and cell death-related *** experimental data showed that ALA,but not GA,suppressed SGIV replication by activating antioxidant and anti-inflammatory responses in the ***,these findings provide a comprehensive resource for understanding host response dynamics during fish iridovirus infection and highlight the antiviral potential of ALA in the prevention and treatment of iridoviral diseases.

关键词： Iridovirus Liver damage Metabolic reprogramming SGIV Alpha-linolenic acid Antiinflammatory

Impact of water table on hierarchically nested groundwater flow system

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Journal of Groundwater Science and Engineering 2024年第2期12卷 119-131页

作者： Jun Zhang Rong-zhe hou Kun Yu Jia-qiu dong Li-he Yin Key Laboratory of Groundwater and Ecology in Arid and Semi-arid Areas Xi'an Center of Geological SurveyChina Geological SurveyXi'an 710054China

Water table configuration gives rise to hierarchically nested groundwater flow ***,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow ***,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional *** on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and *** criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow ***,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and *** applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow *** study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns.

关键词： Water table configuration Groundwater flow pattern Analytical models Top boundary condi-tions Ordos Plateau

Inhibition of EGFR attenuates EGF-induced activation of retinal pigment epithelium cell via EGFR/AKT signaling pathway

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1018-1027页

作者： Yu-Sheng Zhu Si-Rui Zhou Hui-Hui Zhang Tong Wang xiao-dong Chen Faculty of Life Sciences and Medicine Northwest UniversityXi’an 710069Shaanxi ProvinceChina First Affiliated Hospital of Northwest University Northwest UniversityXi’an 710069Shaanxi ProvinceChina Department of Ophthalmology Xi’an No.1 HospitalXi’an 710002Shaanxi ProvinceChina Shaanxi Institute of Ophthalmology Shaanxi Provincial Key Lab of OphthalmologyClinical Research Center for Ophthalmology Diseases of Shaanxi ProvinceXi’an 710002Shaanxi ProvinceChina

AIM:To explore the effect of epidermal growth factor receptor(EGFR)inhibition by erlotinib and EGFR siRNA on epidermal growth factor(EGF)-induced activation of retinal pigment epithelium(RPE)***:Human RPE cell line(ARPE-19 cells)was activated by 100 ng/mL *** and EGFR siRNA were used to intervene EGF *** viability,proliferation,and migration were detected by methyl thiazolyl tetrazolium(MTT)assay,bromodeoxyuridine(BrdU)staining assay and wound healing assay,***/protein kinase B(AKT)pathway proteins and N-cadherin,α-smooth muscle actin(α-SMA),and vimentin were tested by Western blot *** was also determined by immunofluorescence ***:EGF treatment for 24h induced a significant increase of ARPE-19 cells’viability,proliferation and migration,phosphorylation of EGFR/AKT proteins,and decreased total EGFR *** suppressed ARPE-19 cells’viability,proliferation and migration through down regulating total EGFR and AKT protein *** also inhibited EGF-induced an increase of proliferative and migrative ability in ARPE-19 cells and clearly suppressed EGF-induced EGFR/AKT proteins phosphorylation and decreased expression of N-cadherin,α-SMA,and vimentin ***,EGFR inhibition by EGFR siRNA significantly affected EGF-induced an increase of cell proliferation,viability,and migration,phosphorylation of EGFR/AKT proteins,and up-regulation of N-cadherin,α-SMA,and vimentin ***:Erlotinib and EGFR-knockdown suppress EGF-induced cell viability,proliferation,and migration via EGFR/AKT pathway in RPE *** inhibition may be a possible therapeutic approach for proliferative vitreoretinopathy(PVR).

关键词： erlotinib epidermal growth factor receptor protein kinase B epithelial-mesenchymal transition retinal pigment epithelium cell