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Astrocytic endothelin-1 overexpression impairs learning and memory ability in ischemic stroke via altered hippocampal neurogenesis and lipid metabolism

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Neural Regeneration Research 2024年第3期19卷 650-656页

作者： Jie li Wen Jiang Yuefang Cai Zhenqiu Ning Yingying Zhou Chengyi wang Sookja Ki Chung Yan Huang Jingbo Sun Minzhen Deng lihua Zhou Xiao Cheng Guangzhou University of Traditional chinese Medicine GuangzhouGuangdong ProvinceChina State Key Laboratory of Dampness Syndrome of chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhouGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Research on Emergency in TCM GuangzhouGuangdong ProvinceChina Department of Anesthesiology West China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Anatomy Sun Yat-Sen School of MedicineSun Yat-Sen UniversityShenzhenGuangdong ProvinceChina Faculty of Medicine Macao University of Science and TechnologyMacao Special Administration RegionChina

Vascular etiology is the second most prevalent cause of cognitive impairment ***-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of ***,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well ***,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,2. days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery *** proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 2. days after ischemic ***,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway *** chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic ***,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.

关键词： astrocytic endothelin-1 dentate gyrus differentially expressed proteins hippocampus ischemic stroke learning and memory deficits lipid metabolism neural stem cells neurogenesis proliferation

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Integrated analyses of transcriptomics and network pharmacology reveal leukocyte characteristics and functional changes in subthreshold depression,elucidating the curative mechanism of Danzhi Xiaoyao powder

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Journal of Traditional chinese Medical sciences 2024年第1期11卷 3-20页

作者： Kunyu li Leiming You Jianhua Zhen Guangrui Huang Ting wang Yanan Cai Yunan Zhang Anlong Xu School of life sciences Bejing University of Chinese MedicineBeijing 102488China School of life sciences Sun Yat-Sen UniversityGuangzhou 510006Chin

Objective:To investigate the molecular mechanism and identify potential drugs for subthreshold depression(SD),and elucidate the detalied mechanism of Danzhi Xiaoyao powder(DZXY)in ***:Using RNA-sequencing,we identified differentially expressed genes(DEGs)in leukocytes of SD compared to healthy controls,deciphered their functions and pathways,and identified the hub genes of *** also assessed changes in leukocyte transcription factor activity in patients with SD using the TElis *** Connectivity Map database was retrieved to screen candidate drugs for *** on network pharmacology,we elucidated the"multi-component,multi-target,and multi-pathway"mechanism of DZXY in the treatment of ***:We identified 1080 DEGs(padj2.fold change)l≥1&protein coding)in the leukocytes of patients with *** DEGs,including hub genes,were primarily involved in immune and inflammatory response-related *** factor activity analysis revealed similarities between the leukocyte transcriptome profile in SD and the conserved transcriptional response to adversities in immune *** Map analysis identified 2. potential drugs for SD treatment,particularly SB-2.2.90 and *** the"Direct Compounds-Direct Targets-Pathways"network for DZXY and SD revealed the curative mechanisms of DZXY in SD,primarily including inflammatory response,lipid metabolism,immune response,and other ***:These results provide new insights into the characteristics and functional changes of leukocytes in SD,partially illustrate the pathogenesis of SD,and suggest potential drugs for *** curative mechanisms of DZXY in SD are also partially elucidated.

关键词： Subthreshold depression Leukocyte mRNAbiomarker CTRA Transcription factor activity CMap Danzhi Xiaoyaopowder Networkpharmacology

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Semaphorin 7A impairs barrier function in cultured human corneal epithelial cells in a manner dependent on nuclear factor-kappa B

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 444-453页

作者： Cheng-Cheng Yang Xiu-Xia Yang Xiao-Jing Zhao Heng wang Zi-Han Guo Kai Jin Yang liu Bin-Hui li Department of Ophthalmology the Fifth Affiliated HospitalSun Yat-sen UniversityZhuhai 519000Guangdong ProvinceChina Department of Ophthalmology Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical UniversityHangzhou 310006Zhejiang ProvinceChina Eye Institute of Xiamen University Fujian Provincial Key Laboratory of Ophthalmology and Visual ScienceSchool of MedicineXiamen UniversityXiamen 361005Fujian ProvinceChina

●AIM:To evaluate the role of semaphorin 7A(Sema7A)and its associated regulatory mechanisms in modulating the barrier function of cultured human corneal epithelial cells(HCEs).●METHODS:Barrier models of HCEs were treated with recombinant human Sema7A at concentrations of 0,12.,2.0,or 500 ng/mL for 2.,48,or 72. in *** electrical resistance(TEER)as well as Dextran-fluorescein isothiocyanate(FITC)permeability assays were conducted to assess barrier *** quantify tight junctions(TJs)such as occludin and zonula occludens-1(ZO-1)at the mRNA level,reverse transcriptionpolymerase chain reaction(RT-PCR)analysis was *** was used to examine the activity of the nuclear factor-kappa B(NF-κB)signaling pathway and the production of TJs *** analyses were employed to localize the ***-linked immunosorbent assay(EliSA)and RT-PCR were utilized to observe changes in interleukin(IL)-1β*** investigate the role of NF-κB signaling activation and IL^(-1)βin Sema7A’s anti-barrier mechanism,we employed 0.1μmol/L IκB kinase 2.IKK2.inhibitor IV or 500 ng/mL IL^(-1)receptor(IL-1R)antagonist.●RESULTS:Treatment with Sema7A resulted in decreased TEER and increased permeability of Dextran-FITC in HCEs through down-regulating mRNA and protein levels of TJs in a time-and dose-dependent manner,as well as altering the localization of ***,Sema7A stimulated the activation of inhibitor of kappa B alpha(IκBα)and expression of IL-1β.The anti-barrier function of Sema7A was significantly suppressed by treatment with IKK2.inhibitor IV or IL-1R antagonists.●CONCLUSION:Sema7A disrupts barrier function through its influence on NF-κB-mediated expression of TJ proteins,as well as the expression of IL-1β.These findings suggest that Sema7A could be a potential therapeutic target for the diseases in corneal epithelium.

关键词： human corneal epithelial barrier function transepithelial electrical resistance zonula occludens-1 occludin nuclear factor-kappa B

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Deep learning-based multi-modal data integration enhancing breast cancer disease-free survival prediction

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Precision Clinical Medicine 2024年第2期7卷 132-145页

作者： Zehua wang Ruichong lin Yanchun li Jin Zeng Yongjian Chen Wenhao Ouyang Han li Xueyan Jia Zijia Lai Yunfang Yu Herui Yao Weifeng Su Guangdong Key Laboratory of Cross-Application of Data Science and Technology Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087China Faculty of Innovation Engineering Macao University of Science and TechnologyTaipaMacao 999078China Department of Computer and Information Engineering Guangzhou Huali CollegeGuangzhou 511325China Department of Pathology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China Guangzhou national Laboratory Guangzhou 510005China Dermatology and Venereology Division Department of Medicine SolnaCenter for Molecular MedicineKarolinska InstitutetStockholm 17177Sweden Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Department of Medical OncologyBreast Tumor CentrePhase I Clinical Trial CentreSun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China The Second Clinical Medical College Southern Medical UniversityGuangzhou 510515China Faculty of Medicine Macao University of Science and TechnologyTaipaMacao 999078China

Background:The prognosis of breast cancer is often unfavorable,emphasizing the need for early metastasis risk detection and accurate treatment *** study aimed to develop a novel multi-modal deep learning model using preoperative data to predict disease-free survival(DFS).Methods:We retrospectively collected pathology imaging,molecular and clinical data from The Cancer Genome Atlas and one independent institution in *** developed a novel Deep Learning Clinical Medicine Based Pathological Gene Multi-modal(DeepClinMed-PGM)model for DFS prediction,integrating clinicopathological data with molecular *** patients included the training cohort(n=741),internal validation cohort(n=184),and external testing cohort(n=95).Result:Integrating multi-modal data into the DeepClinMed-PGM model significantly improved area under the receiver operating characteristic curve(AUC)*** the training cohort,AUC values for 1-,3-,and 5-year DFS predictions increased to 0.979,0.957,and 0.871,while in the external testing cohort,the values reached 0.851,0.878,and 0.938 for 1-,2.,and 3-year DFS predictions,*** DeepClinMed-PGM's robust discriminative capabilities were consistently evident across various cohorts,including the training cohort[hazard ratio(HR)0.02.,95%confidence interval(CI)0.0016-0.046,P1],the internal validation cohort(HR 0.117,95%CI 0.041-0.334,P1),and the external cohort(HR 0.061,95%CI 0.017-0.2.8,P1).Additionally,the DeepClinMed-PGM model demonstrated C-index values of 0.92.,0.82.,and 0.864 within the three cohorts,***:This study introduces an approach to breast cancer prognosis,integrating imaging and molecular and clinical data for enhanced predictive accuracy,offering promise for personalized treatment strategies.

关键词： breast cancer multi-modality deep learning pathological disease-free survival

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腰椎骨髓MR T1 mapping影像组学预测儿童急性淋巴细胞白血病临床危险度

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中国医学影像技术 2024年第9期40卷 1284-1288页

作者：王立英李辛子李颖郑美敏陈森叶兆祥王春祥天津市儿童医院/天津大学儿童医院医学影像科天津300400 天津医科大学肿瘤医院国家恶性肿瘤临床医学研究中心放射科天津300060 天津市儿童医院/天津大学儿童医院血液科天津300400

目的观察腰椎骨髓MR T1 mapping影像组学预测儿童急性淋巴细胞白血病(ALL)临床危险度的价值。方法前瞻性对77例初诊ALL患儿采集腰椎骨髓T1 mapping,以3D Slicer软件分割L3椎体感兴趣体积(VOI)、提取2.60个影像组学特征并筛选最佳特征。... 详细信息

目的观察腰椎骨髓MR T1 mapping影像组学预测儿童急性淋巴细胞白血病(ALL)临床危险度的价值。方法前瞻性对77例初诊ALL患儿采集腰椎骨髓T1 mapping,以3D Slicer软件分割L3椎体感兴趣体积(VOI)、提取2.60个影像组学特征并筛选最佳特征。以8∶2.例将患儿分为训练集与测试集,分别以逻辑回归(LR)、支持向量机(SVM)及随机森林(RF)分类器基于最佳特征建立影像组学模型,于训练集进行训练、于测试集进行验证;结合初诊危险度及MR检查后患儿对于化学治疗的反应评估其临床危险度,以采用受试者工作特征(ROC)曲线及曲线下面积(AUC)评估模型预测效能。结果低-中危组52.、高危组2.例。训练集含44例低-中危及17例高危,测试集含8例低-中危及8例高危患儿。共获得12.最佳影像组学特征,以之建立的RF模型在训练集中的敏感度及准确率均为100%,在测试集的敏感度(50.00%)及准确率(75.00%)均较低,提示存在过拟合;LR模型在测试集AUC(0.95)稍高于SVM模型(0.92.但差异无统计学意义(P>0.05),而其准确率一致。结论腰椎骨髓T1 mapping LR及SVM影像组学模型均可用于预测儿童ALL临床危险度;LR模型预测效能较佳。

关键词：儿童白血病磁共振成像影像组学前瞻性研究

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Dynamic compression behavior of TiZrNbV refractory high-entropy alloys upon ultrahigh strain rate loading

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Journal of Materials Science & Technology 2023年第30期161卷 201-219页

作者： Kerong Ren Hongyang liu rong Ma sen Chen Siyuan Zhang Ruixin wang rong Chen Yu Tang Shun li Fangyun Lu College of sciences National University of Defense TechnologyChangsha 410008China Aviation Maintenance NCO academy Air Force Engineering UniversityXinyang 464001China The Peac Institute of Multiscale sciences Chengdu 610031China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410008China

In this study,the dynamic compressive response behavior of a body-centered cubic(BCC)single-phase TiZrNbV refractory high-entropy alloy(RHEA)was investigated under impact at speeds of 313.1584 m s^(-1)using two-stage,gas-gun-driven,high-speed plate-impact experiments;recovery sample analysis;and theoretical *** strain rate and pressure were approximately 10^(7) s^(−1) and 5.07-2..37 GPa,*** results showed that the TiZrNbV RHEA had a Hugoniot elastic limit of 4.12.5.86 GPa and a spall strength of 1.84-2.03 *** initial yield strength of the alloy showed a st{2. strain-rate dependence and could be described by the modified Zerilli-Armst{2. model,while the phonon-damping effect was the main reason for its high strain-rate *** analysis showed that the dynamic deformation of the TiZrNbV RHEA was controlled by the dislocation slip,dislocation proliferation,intersection of the deformation bands,and grain *** analysis also showed that the intergranular,transgranular,and mixed-type cracks dominated the spall failure of the *** dynamic Hall-Petch effect and pinning from the lattice distortion led to high dynamic yield *** critical strain rate for the phonon drag effect was positively related to the relative atomic mass and local strain field of the *** the experimental loading range,the RHEA showed good structural stability,and simultaneously,the theoretical calculation method for the equation of state based on a cold-energy mixture could accurately predict its shock-response *** valence-electron concentration(VEC)had a direct effect on the shock-compression properties of the HEAs;higher VEC implied more difficulty in compressing the *** findings of this study provide insights into understanding the mechanical response characteristics of RHEAs under extreme conditions such as high-speed impact and ultrahigh strain-rate loading.

关键词： Refractory high-entropy alloys Shock compression Spall Dynamic yield Equation of state Ultrahigh strain rate

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2.09-2.18年中国9省(自治区)成年人乳品摄入现状及变化趋势

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营养学报 2024年第2期46卷 112-119页

作者：王柳森胡霄刘梦冉陈黎黎王惠君王志宏中国疾病预防控制中心营养与健康所北京100050 荣华社区卫生服务中心北京100176

目的了解中国9省(自治区)成年人乳品摄入和消费状况变化特征。方法利用2.09、2.11、2.15、2.18年“中国健康与营养调查”(CHNS)数据,选择具有完整膳食调查数据的18岁及以上成年人作为研究对象,共34984人。分析不同性别、年龄、城乡、地... 详细信息

目的了解中国9省(自治区)成年人乳品摄入和消费状况变化特征。方法利用2.09、2.11、2.15、2.18年“中国健康与营养调查”(CHNS)数据,选择具有完整膳食调查数据的18岁及以上成年人作为研究对象,共34984人。分析不同性别、年龄、城乡、地域、教育程度、收入水平人群乳品摄入及消费状况。结果2.09-2.18年中国9省(自治区)成年人乳品消费率提高了6.2.个百分点,乳品平均摄入量呈增长趋势。在消费人群中(在调查的3 d中任意1d消费了乳品的成年人被视为乳品消费人群。),乳品平均摄入量呈现下降趋势,2.18年成年人乳品平均摄入量比2.09年减少了30.11 g/d。女性、65岁及以上老年人、城市、东部、高中及以上和高收入人群的乳品消费率相对其他人群较高。结论中国成年人乳品摄入和消费状况有所改善,但是仍远低于《中国居民膳食指南(2.2.)》中300~500 g/d的推荐摄入量。

关键词：成年人乳品消费率摄入量变化趋势

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LAMOST的“Unknown”光谱分类研究:ODS-YOLOv7模型

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光谱学与光谱分析 2024年第7期44卷 1960-1967页

作者：王晓敏高军萍蒲源邱波张健楠闫静李荣河北工业大学天津300400 广东白云学院广东广州510450 中国科学院国家天文台北京100012

天体识别是天文新发现和深入研究天体的基础。在LAMOST DR8 v1.0发布的低分辨率光谱数据中有约53万条因没有类别标签而被命名为“Unknown”的光谱,其中有88.56%的光谱信噪比在0~10之间,对这批光谱的研究分析将增加LAMOST的有效数据产出... 详细信息

天体识别是天文新发现和深入研究天体的基础。在LAMOST DR8 v1.0发布的低分辨率光谱数据中有约53万条因没有类别标签而被命名为“Unknown”的光谱,其中有88.56%的光谱信噪比在0~10之间,对这批光谱的研究分析将增加LAMOST的有效数据产出。该研究为“Unknown”光谱的分类设计了一种ODS-YOLOv7模型。它是一种端到端的类别预测模型,通过添加一维卷积注意力模块以提高光谱识别能力。在经过一批信噪比在0~10之间的已知类别光谱训练后,ODS-YOLOv7可以学习到低信噪比光谱的有效特征,进而实现对“Unknown”光谱的类别预测。实验表明,该模型在已知类别标记的低信噪比恒星、星系、类星体的光谱识别中,F1-score分别为0.98、0.95、0.95;同时在与传统算法KNN、RF、DT、SVM和深度学习算法1D CNN、1DSSCNN、ResNet、Densenet、VIT对比实验中取得相对最好的效果。实验结果还给出了ODS-YOLOv7模型对DR8 v1.0中信噪比在0~10的“Unknown”光谱预测置信度分布,在预测类别为恒星、星系、类星体任务中,有92.的分类置信度在60%以上。为保证模型输出质量,本文只选取分类置信度大于99%的光谱类别作为输出结果。以此为依据,在DR8 v1.0和DR9 v0发布的全部“Unknown”光谱中分别有37.19%和47.03%被ODS-YOLOv7模型预测出类别。此外,还增加人工认证以检验该模型预测的正确性。为提升模型的可解释性,参照了二维图像特征可视化的Grad-CAM方法,将其改进为适合于可视化一维光谱数据特征的算法。其结果表明该模型可自动关注到不同的分类特征,使得该模型非常适用于低信噪比“Unknown”光谱的类别预测。

关键词： Unknown光谱分类 ODS-YOLOv7 低信噪比 LAMOST 特征可视化

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Distinguished biological adaptation architecture aggravated population differentiation of Tibeto-Burman-speaking people

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Journal of Genetics and Genomics 2024年第5期51卷 517-530页

作者： Yuntao Sun Mengge wang Qiuxia Sun Yan liu Shuhan Duan Zhiyong wang Yunyu Zhou Jun Zhong Yuguo Huang Xinyu Huang Qingxin Yang Xiangping li Haoran Su Yan Cai Xiucheng Jiang Jing Chen Jiangwei Yan Shengjie Nie liping Hu Junbao Yang Renkuan Tang Chuan-Chao wang Chao liu Xiaohui Deng libing Yun Guanglin He West china School of Basic Science&Forensic Medicine Sichuan UniversityChengduSichuan 610041China Institute of Rare Diseases West China Hospital of Sichuan UniversitySichuan UniversityChengduSichuan 610000China Center for Archaeological Science Sichuan UniversityChengduSichuan 610000China Faculty of Forensic Medicine Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouGuangdong 510275China Guangzhou Forensic Science Institute GuangzhouGuangdong 510055China Department of Forensic Medicine College of Basic MedicineChongqing Medical UniversityChongqing 400331China School of Clinical Medical sciences North Sichuan Medical CollegeNanchongSichuan 637100China School of Basic Medical sciences North Sichuan Medical CollegeNanchongSichuan 637100China School of Forensic Medicine Kunming Medical UniversityKunmingYunnan 650500China School of Stomatology North Sichuan Medical CollegeNanchongSichuan 637100China Department of Medical Laboratory North Sichuan Medical CollegeNanchongSichuan 637007China School of life sciences Xiamen UniversityXiamenFujian 361005China Anti-Drug Technology Center of Guangdong Province GuangzhouGuangdong 510230China School of Forensic Medicine Shanxi Medical UniversityJinzhongShanxi030600China

Tibeto-Burman(TB)people have endeavored to adapt to the hypoxic,cold,and high-UV high-altitude environments in the Tibetan Plateau and complex disease exposures in lowland rainforests since the late Paleolithic ***,the full landscape of genetic history and biological adaptation of geographically diverse TB-speaking people,as well as their interaction mechanism,remain ***,we generate a whole-genome meta-database of 500 individuals from 39 TB-speaking populations and present a comprehensive landscape of genetic diversity,admixture history,and differentiated adaptative features of geographically different TB-speaking *** identify genetic differentiation related to geography and language among TB-speaking people,consistent with their differentiated admixture process with incoming or indigenous ancestral source populations.A robust genetic connection between the Tibetan-Yi corridor and the ancient Yellow River people supports their Northern {2. origin *** finally report substructure-related differentiated biological adaptative signatures between highland Tibetans and Loloish *** signatures associated with the physical pigmentation(EDAR and SLC2.A5)and metabolism(ALDH9A1)are identified in Loloish people,which differed from the high-altitude adaptative genetic architecture in ***-related genomic resources provide new insights into the genetic basis of biological adaptation and better reference for the anthropologically informed sampling design in biomedical and genomic cohort research.

关键词： Tibeto-Burman people Genetic profile Natural selection Genetic diversity Biological adaptation

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Driving factors behind multiple populations

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Science china(Physics,Mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun Huang Baitian Tang Chengyuan li Doug Geisler Mario Mateo Ying-Yi Song Holger Baumgardt Julio A.Carballo-Bello Yue {2. Jundan Nie Bruno Dias JoséG.Fernández-Trincado School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai 519082China Departamento de Astronomía Universidad de ConcepcionConcepcionChile Instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile Departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile Department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap Department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada School of Mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia Instituto de Alta Investigación Universidad de TarapacáAricaChile CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile Instituto de Astronomía Universidad Católica del NorteAntofagastaChile

Star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical ***,the presence of chemical anomalies in globular clusters(GCs),called multiple stellar populations(MPs),has challenged star formation theories in dense *** studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of *** the limit between clusters with/without MPs in physical parameter space is crucial to reveal the driving mechanism behind their *** this study,we look for MP signals in Whiting 1,which is traditionally considered a young *** the Magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting *** measured the C and N abundances from the CN and CH spectral indices.C and N abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that MPs are absent from Whiting *** these findings with literature studies,we propose a limit in the metallicity *** compactness index parameter space,which relatively clearly separates star clusters with/without MPs(GCs/open clusters).This limit is physically *** a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex *** proposed limit also impacts our understanding of the formation of the Sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 Gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for MP formation.

关键词： stellar galactic galaxy

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