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Four new diterpenoid alkaloids with antitumor effect from Aconitum nagarum var. heterotrichum

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Chinese Chemical Letters 2017年第2期28卷 358-361页

作者： Da-Ke Zhao Xing-Qiao Shi Li-Mei Zhang Dong-Qiong Yang hua-chun guo Yan-Ping Chen Yong Shen School of Agriculture Yunnan University Kunming 650091 China College of Agriculture and Biotechnology Yunnan Agricultural University Kunming 650201 China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China

Four new diterpenoid alkaloids,nagaconitines A-D（1-4）,were isolated from the roots of Aconitum nagarum *** structures were elucidated as 8-（4＇-hydroxylbutyryl） aconitine（1）,15-oxo-13-deoxyludaconitine（2）,15-hydroxyldelphisine（3）,and 14-hydroxyl-2- acetoxyspiradine C（4）based on extensive UV,IR,MS,1D NMR and 2D NMR *** 3-4 showed inhibition of cancer cell line SK-OV-3 with 31%（IC_（50） 43.78 μmol/L） and 24%（IC_（50） 32.14 μmol/L）,respectively.

关键词： Ranunculaceae Aconitum nagarum var.heterotrichum Diterpenoid alkaloids Nagaconitines A-D Antitumor activity

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China(Life Sciences) 2025年第1期68卷 272-283页

作者： Yuwei hua Yizhi Zhang Zhenming guo Shan Bian Yong Zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level,limiting their applications in biological ***,we introduce ImSpiRE,an image feature-aided spatial resolution enhancement method for in situ capturing spatial *** the information stored in histological images,ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution,together with extending the gene expression profiles into unmeasured *** to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains,signaling communication patterns,and spatiotemporal characterization.

关键词： spatial transcriptome histological images spatial resolution enhancement

New Insights on Gamma-Ray Burst Radiation Mechanisms from Multiwavelength Observations

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Research in Astronomy and Astrophysics 2025年第2期25卷 3-12页

作者： Yu-hua Yao Fang-Sheng Min Shi Chen Yi-Qing guo College of Physics Chongqing University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Wisconsin Ice Cube Particle Astrophysics Center University of Wisconsin–Madison University of Chinese Academy of Sciences School of Physics and Astronomy Yunnan University Tianfu Cosmic Ray Research Center

The study of high-energy gamma-ray emission from gamma-ray bursts(GRBs) involves complex synchrotron radiation and synchrotron self-Compton(SSC) scattering mechanisms with multiple parameters exhibiting a wide distribution. Recent advancements in GRB research, particularly the observation of very high energy(VHE,>100 Ge V) radiation, have ushered in a new era of multiwavelength exploration, offering fresh perspectives and limitations for understanding GRB radiation mechanisms. This study aimed to leverage VHE observations to refine constraints on synchrotron + SSC radiation from electrons accelerated by forward shocks. By analyzing two external environments—the uniform interstellar medium and stratified stellar wind medium, we conducted spectral and variability fitting for five specific bursts(GRB 180720B, GRB 190114C, GRB 190829A, GRB 201216C, and GRB 221009A) to identify the optimal parameters characterizing these events. A comparative analysis of model parameter distributions with and without VHE radiation observations reveals that the magnetic energy equipartition factor εBis more concentrated with VHE emissions. This suggests that VHE emissions may offer greater constraints on this microphysical parameter. Additionally, we found that the energy budget between VHE and ke V–Me V γ-ray emissions under the SSC radiation exhibits an almost linear relationship, which may serve as a tool to differentiate radiation mechanisms. We anticipate future statistical analyses of additional VHE bursts to validate our findings.

关键词： (transients:) gamma-ray bursts gamma-rays: ISM radiation mechanisms: non-thermal

Mesozoic multi-direction collision tectonic evolution of the Ordos Basin, China: Insights from the detrital zircon and apatite (U-Th)/He analyses

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China Geology 2025年第1期8卷 141-158页

作者： Yin Chen Jian-guo Li Lu-lu Chen hua-lei Zhao Tianjin Center of China Geological Survey Tianjin 300170China Key Laboratory of Uranium Geology China Geological SurveyTianjin 300170China Cores and Samples Center of Natural Resources China Geological SurveyLangfang 065201China Key Laboratory of Tectonics and Petroleum Resources China University of Geosciences(Wuhan)Wuhan 430074China

The Ordos Basin(OB)in the western part of the North China Craton(NCC),was located at the jointed area of multi-plates and has recorded the Mesozoic tectonic *** tectonic evolution in the Mesozoic is significant to understand the tectonic transformation of the northern margin of the *** this work,the detrital zircon and apatite(U-Th)/He chronological system were analyzed in the northern part of the OB,and have provided new evidence for the regional tectonic ***(U-Th)/He chronological data states the weighted ages of 240‒235 Ma,141 Ma with the peak distribution of 244 Ma,219 Ma,173 Ma,147‒132 *** thermal evolution,geochronological data,and regional unconformities have proved four stages of regional tectonic evolution for the OB and its surroundings in the Mesozoic:(1)The Late Permian-Early Triassic;(2)the Late Triassic-Early Jurassic;(3)the Late Jurassic-Early Cretaceous;(4)the Late Cretaceous-Early *** is indicated that the multi-directional convergence from the surrounding tectonic units has controlled the Mesozoic tectonic evolution of the ***-stage tectonic evolution reflected the activation or end of different plate movements and provided new time constraints for the regional tectonic evolution of the NCC in the Mesozoic.

关键词： Zircon and Apatite(U-Th)/He Tectonic evolution Geochronology Four stages of regional tectonic Ordos Basin Oil-gas-bearing basin Multi-direction collision Oil-gas exploration engineering Mesozoic North China Craton

Xanthones from Garcinia pedunculata and Garcinia nujiangensis and their anti-inflammatory activity

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Chinese Journal of Natural Medicines 2025年第2期23卷 225-233页

作者： Xiaojie Fan Yufeng Jia Jiaxin guo Jinyuan Yang Dahong Li Huiming hua Key Laboratory of Structure-Based Drug Design & Discovery Ministry of Education and School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University

Ten novel xanthones,garpedunxanthones A-G（1-5,6a/6b,7a/7b） and nujiangxanthone Q（8）,along with sixteen known analogs（9-24）,were isolated from Garcinia pedunculata and *** structures were elucidated through high-resolution electrospray ionization mass spectrometry（HR-ESI-MS） data,comprehensive nuclear magnetic resonance（NMR） spectroscopic analyses,and electronic circular dichroism（ECD） *** compounds without cytotoxicity were assessed for anti-inflammatory properties by measuring the inhibition of nitric oxide（NO） production in lipopolysaccharide（LPS）-induced ***-activity relationships are also *** 7b,19,and 21 exhibited significant anti-inflammatory activity with IC50values of 16.44±0.69,14.28±0.78,and 10.67±3.28 μmol·L-1,***-linked immunosorbent assay（ELISA） demonstrated that compounds 7b,19,and 21 inhibited the expression of pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent *** inhibitory effect of compo und 21 on IL-6 at 20 μmol·L-1was comparable to that of the positive *** network pharmacology studies,potential targets of compounds and inflammation were identified from PharmMapper and GeneCards *** Ontology（GO） and Kyoto Encyclopedia of Genes and Genomes（KEGG） enrichment analysis revealed that the overlapped targets were intricately associated with major pathogenic processes linked to inflammation,including positive regulation of mitogen-activated protein kinase（MAPK） cascade,protein kinase activity,NO synthase regulator activity,MAPK signaling pathway,and EGFR tyrosine kinase inhibitor resistance.

关键词： Anti-inflammation Garcinia nujiangensis Garcinia pedunculata Network pharmacology Xanthones

B2-CuZr reinforced amorphous alloy matrix composites:A review

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China Foundry 2025年第1期22卷 1-11页

作者： Wei guo Run-hua huang Zhen Zhang Mi Zhao Jin-cheng Wang Yan-qiang Qiao Shu-lin Lü Shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Research Institute of huazhong University of Science and Technology in Shenzhen Shenzhen 518057GuangdongChina

B2-CuZr phase reinforced amorphous alloy matrix composites has become one of the research hotspots in the field of materials science due to the“transformation-induced plasticity”phenomenon,which makes the composites show better macroscopic plastic deformability and obvious work-hardening behavior compared to the conventional amorphous alloy matrix composites reinforced with ductile ***,the in-situ metastable B2-CuZr phase tends to undergo eutectoid decomposition during solidification,and the volume fraction,size,and distribution of B2-CuZr phase are difficult to control,which limits the development and application of these *** date,much efforts have been made to solve the above problems through composition optimization,casting parameter tailoring,and post-processing *** this study,a review was given based on relevant studies,focusing on the predictive approach,reinforcing mechanism,and microstructure tailoring methods of B2-CuZr phase reinforced amorphous alloy matrix *** research focus and future prospects were also given for the future development of the present composite system.

关键词： amorphous alloy matrix composite B2-CuZr phase plasticity microstructure tailoring

The miR3367–lncRNA67–GhCYP724B module regulates male sterility by modulating brassinosteroid biosynthesis and interacting with Aorf27 in Gossypium hirsutum

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Journal of Integrative Plant Biology 2025年第1期67卷 169-190页

作者： Anhui guo Hushuai Nie Huijing Li Bin Li Cheng Cheng Kaiyun Jiang Shengwei Zhu Nan Zhao Jinping hua Laboratory of Cotton Genetics Genomics and Breeding/Joint Laboratory for International Cooperation in Crop Molecular BreedingMinistry of Education/Beijing Key Laboratory of Crop Genetic ImprovementCollege of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100193China Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of SciencesBeijing 100093China

Cytoplasmic male sterile(CMS)lines play a crucial role in utilization of heterosis in crop ***,the mechanism underlying the manipulation of male sterility in cotton by long non-coding RNA(lncRNA)and brassinosteroids(BRs)remains ***,using an integrative approach combining lncRNA transcriptomic profiles with virus-induced gene silencing experiments,we identify a flower budspecific lncRNA in the maintainer line 2074B,lncRNA67,negatively modulating with male sterility in upland cotton(Gossypium hirsutum).lncRNA67positively regulates cytochrome P274B(GhCYP724B),which acted as an eTM(endogenous target mimic)for *** suppression of GhCYP724B induced symptoms of BR deficiency and male semisterility in upland cotton as well as in tobacco,which resulted from a reduction in the endogenous BR ***724B regulates BRs synthesis by interacting with GhDIM and GhCYP90B,two BRs biosynthesis ***,GhCYP724B suppressed a unique chimeric open reading frame(Aorf27)in 2074A mitochondrial *** expression of Aorf27 in yeast inhibited cellular growth,and over expression of Aorf27 in tobacco showed male ***,the results proved that the miR3367–lncRNA67–GhCYP724B module positively regulates male sterility by modulating BRs *** findings uncovered the function of lncRNA67–GhCYP724B in male sterility,providing a new mechanism for understanding male sterility in upland cotton.

关键词： brassinosteroids GhCYP724B lncRNA67 male sterility mitochondrial Aorf27 upland cotton(G.hirsutum)

Positive effect of Mo on mechanical properties of a Ni-42W-10Co-xMo medium heavy alloy

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China Foundry 2025年第1期22卷 108-116页

作者： guo-xin Cao Jian-xin Dong Yong-sheng He He Jiang Fang Hao Zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi'an Superalloy Technology Co. Ltd.Xi’an 710299China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina

In this study,a novel Ni-W-Co-Mo medium heavy alloy(MHA)was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-x Mo alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypo-eutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0 to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-x Mo alloys is Mo-induced solid solution strengthening and precipitation strengthening.

关键词： medium-heavy alloys Ni-based alloy mechanical properties solid solution strengthening precipitation strengthening

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云南地区地壳磁异常与地质构造

地球物理学报 2017年第9期60卷 3493-3504页

作者：文丽敏康国发白春华高国明郑安燃安柏林云南大学地球物理系昆明650091

根据美国地球物理数据中心的地磁场模型(NGDC-720),研究云南地区地壳磁异常的空间变化,包括磁异常及其梯度的分布、磁异常随高度的衰减、不同波长成分对总体磁异常的贡献.比较磁异常与重力异常、大地热流、地震活动等地球物理信息的异... 详细信息

根据美国地球物理数据中心的地磁场模型(NGDC-720),研究云南地区地壳磁异常的空间变化,包括磁异常及其梯度的分布、磁异常随高度的衰减、不同波长成分对总体磁异常的贡献.比较磁异常与重力异常、大地热流、地震活动等地球物理信息的异同特征,探讨地壳磁异常与地质构造的关系.研究结果表明:丽江—小金河、红河断裂带以西的三江、滇西造山带的异常较弱,菱形地块的异常相对较强.研究区域的地壳磁异常主要是弱磁性基底背景下叠加的浅源磁性体产生.卫星磁异常显示滇中坳陷区具有清晰的偶极场特征.沿红河断裂带分布的正负磁异常带与断裂构造走向一致.围限菱形地块的丽江—小金河断裂、红河断裂、康定—奕良—水城断裂和弥勒—师宗—水城断裂带是磁异常的强弱过渡带.强烈地震发生的地点、大地热流值高的地区,地壳磁异常为负值或相对较弱.

关键词：地磁场模型地壳磁异常地质构造云南地区