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A Study of Binary Stellar Population Synthesis of Elliptical Galaxies

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Chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 669-679页

作者： Zhong-Mu li feng-hui zhang zhan-wen han National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049

We determined the relative stellar ages and metallicities of about 80 elliptical galaxies in both low and high density environments using the latest binary stellar population （BSP） synthesis model and tested the predictions of a recent hierarchical formation model that adopted the new ACDM cosmology. The stellar ages and metallicities were estimated from two high-quality published spectra line indices, the Hβ and [MgFe] indices. The results show that the stellar populations of elliptical galaxies are older than 3.9 Gyr and more metal rich than 0.02. Most of our results are in agreement with the model predictions; （1） elliptical galaxies in denser environment are redder and have older populations than field galaxies; （2） elliptical galaxies with more massive stellar components are redder and have older and more metal rich populations than less massive ones; （3） the most massive galaxies have the oldest and most metal rich stars. However, some of our results differ from the model predictions on the metallicity distributions of low- and high-density elliptical galaxies and the dependence on the distance to the cluster center.

关键词： galaxies stellar content- galaxies formation- galaxies elliptical and lenticular, cD

Model-Synthesized Rate of Type Ia Supernovae and its Influence on the Chemical Enrichment of the ISM

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Chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 63-70页

作者： wen Guo feng-hui zhang Xiang-Cun Meng Zhong-Mu li zhan-wen han National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049

Using Hurley＇s rapid binary stellar evolution code, we have studied the model-synthesized rate of Type Ia Supernovae （SNe Ia） and its influence on the chemical enrichment of the interstellar medium ejected by stellar populations. We adopt two popular scenarios, i.e., single degenerate scenario （SD） and double degenerate scenario （DD）, for the progenitors of SNe Ia to calculate the rates of SNe Ia. Rates calculated in this work agree with that of Hachisu et al. and han ＆ Podsiadlowski, but are different from that usually adopted in chemical evolution models of galaxies. We apply the rates of SNe Ia to the chemical enrichment （especially Fe enrichment）, then compare the results with previous studies. As known SNe Ia slightly affect the enrichment of C, N, O and Mg elements, while significantly affect the enrichment of Fe. We find that the occurrence and the value of the Fe enrichment in our models are earlier and smaller than that commonly adopted in chemical evolution models. We also study the evolution of [Mg/Fe] ratios, which are almost reciprocals of the Fe enrichment. The study may provide constraints on the free parameters of chemical evolution models of galaxies and evolutionary population synthesis.

关键词： galaxies abundances - supernovae general-galaxies stellar content-white dwarfs

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： wenda zhang Weimin Yuan Zhixing ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing zhang Chen zhang Shuang-Nan zhang Yonghe zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier liming Dou Rob Eyles-Ferris Zhou Fan Hua feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei wenxiong li Bifang liu Mingjun liu Xing liu Yuan liu Zhu liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui li Junfei li Longhui li Maoshun li Wei li Zhengda li Tianying lian Congzhan liu Heyang liu Huaqiu liu fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan liming Song hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan zhang Mo zhang wenjie zhang Zhen zhang Zhen zhang Ziliang zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space Sciences University of Science and Technology of China Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Two New Ursane-type Triterpenoid Glycosides from Ilex Cornuta

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Current Medical Science 2018年第6期38卷 976-981页

作者： Hai-xia zhan Juan li han-li RUAN Peng zhang hui-fang PI School of Pharmacy Tongji Medical CollegeHuazhong University of Seience and TechnologyHubei Key Laboratory of Natural Medicinal Chemistry and Resource EvaluationWuhan 430030China Department of Pharmacy Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Ilex cornuta (***)is a traditional Chinese medicine (TCM)that has been used in clinical practice for hundreds of *** order to provide more information about the chemical basis of its pharmacological effects,phytochemical investigation on the roots of L cornuta was conducted in this *** roots of the plant were firstly extracted with 95% EtOH,and then the crude was partitioned with petroleum ether,EtOAc and n-butyl *** chromatographies were employed to isolate the crude step by step and the crude was further purified by semipreparative high performance liquid chromatography (HPLC).As a result,two new triterpenoid saponins (1,2),together with 12 known compounds (3-14),were isolated from the roots of I. *** structures were determined based on nuclear magnetic resonance (NMR),mass spectrum (MS)technologies,chemical reactions as well as gas chromatography (GC).Compounds 4,6,8,11,12 and 13 were isolated from this genus for the first *** structures of compounds 1 and 2 were determined as 3β-O-α-D-xylopyranosyl-(1→3)-α-L-2-O-acetylarabinopyranosyl-(1→2)-β-D glucopyranosyl-23-hydroxyl-20α(H)-urs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (1)and 3β-O-α-D-xylopyranosly-(1→3)-α-L-2-O-acetylarabinopyranosyl-(1→2)-β-D-glucopyranosyl-19α,23-dihydroxyl-20α(H)-urs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester(2).

关键词： Ilex cornuta aquifoliaceae triterpenoids

Probing cell membrane integrity using a histone-targeting protein nanocage displaying precisely positioned fluorophores

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Nano Research 2023年第1期16卷 894-904页

作者： Ti fang Chaoqun li Ao liang hui zhang Fan zhang Xian-En zhang Yi-Yu Yang feng li Guangzhou Women and Children’s Medical Center Guangzhou Medical UniversityGuangzhou 510120China State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China Faculty of Synthetic Biology Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Cell membrane integrity is fundamental to the normal activities of cells and is involved in both acute and chronic ***,we report a probe for analyzing cell membrane integrity developed from a 9 nm-sized protein nanocage named Dps via fluorophore conjugation with high spatial precision to avoid *** probe cannot enter normal live cells but can accumulate in dead or live cells with damaged membranes,which,interestingly,leads to weak cytoplasmic and strong nuclear *** differential staining is found attributed to the high affinity of Dps for histones rather than DNA,providing a staining mechanism different from those of known membrane exclusion probes(MEPs).Moreover,the Dps nanoprobe is larger in size and thus applies a more stringent criterion for identifying severe membrane damage than currently available *** study shows the potential of Dps as a new bioimaging platform for biological and medical analyses.

关键词： protein engineering fluorescent probes nanoparticles cell membrane damage ferritin superfamily

Gualou Guizhi decoction promotes neurological functional recovery and neurogenesis following focal cerebral ischemia/reperfusion

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Neural Regeneration Research 2018年第8期13卷 1408-1416页

作者： Jing han Ji-Zhou zhang Zhi-feng Zhong Zuan-fang li wen-Sheng Pang Juan Hu li-Dian Chen Institute of Materia Medica Fujian Academy of Traditional Chinese Medicine Fuzhou Fujian Province China Fujian University of Traditional Chinese Medicine Fuzhou Fujian Province China The Second People's Hospital of Fujian Province Fuzhou Fujian Province China

Recovery following stroke involves neurogenesis and axonal remodeling within the ischemic brain. Gualou Guizhi decoction （GLGZD） is a Chinese traditional medicine used for the treatment of post-stroke limb spasm. GLGZD has been reported to have neuroprotective effects in cerebral ischemic injury. However, the effects of GLGZD on neurogenesis and axonal remodeling following cerebral ischemia remain unknown. In this study, a rat model of focal cerebral ischemia/reperfusion was established by middle cerebral artery occlusion. Neurologi- cal function was assessed immediately after reperfusion using Longa＇s 5-point scoring system. The rats were randomly divided into vehicle and GLGZD groups. Rats in the sham group were given sham operation. The rats in the GLGZD group were intragastrically administered GLGZD, once daily, for 14 consecutive days. The rats in the vehicle and sham groups were intragastrically administered distilled water. Modified neurological severity score test, balance beam test and foot fault test were used to assess motor functional changes. Nissl staining was performed to evaluate histopathological changes in the brain. Immunofluorescence staining was used to examine cell proliferation using the marker 5-bromo-2＇-deoxyuridine （BrdU） as well as expression of the neural precursor marker doublecortin （DCX）, the astrocyte marker glial fibrillary acidic protein （GFAP） and the axon regeneration marker growth associated protein-43 （GAP-43）. GLGZD substan- tially mitigated pathological injury, increased the number of BrdU, DCX and GFAP-immunoreactive cells in the subventricular zone of the ischemic hemisphere, increased GAP-43 expression in the cortical peri-infarct region, and improved motor function. These findings suggest that GLGZD promotes neurological functional recovery by increasing cell proliferation, enhancing axonal regeneration, and in- creasing the numbers of neuronal precursors and astrocytes in the peri-infarct area.

关键词： nerve regeneration Gualou Guizhi decoction cell proliferation neurogenesis neuroblast astrocyte axon remodeling ischemic stroke Chinese medicine compound neural regeneration

SOMO-HOMO level conversion in triarylmethyl-cored N-heterocyclic carbene-Au(I)complexes triggered by selecting coordination halogens

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Chinese Chemical Letters 2024年第11期35卷 512-516页

作者： Le zhang hui-Yu Xie Xin li li-Ying Sun Ying-feng han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China

Conventionally,organic radicals adhere to the Aufbau principle,the energy level of the singly occupied molecular orbital(SOMO)is not below the highest occupied molecular orbital(HOMO),but somewhat abnormal phenomena have appeared *** this study,we introduce a novel strategy by incorporating unique NHC-Au-X units into a tris(2,4,6-trichlorophenyl)methyl(TTM)system to create metal-involved open-shell complexes,denoted as TTM-NHC-Au-X(X=I,Br,or Cl).Density-functional theory calculations were used to predict an inversion in the energy of the SOMO and highest doubly occupied molecular orbital(HOMO)of TTM-NHC-Au-I,which is supported by experimental *** radicals TTM-NHC-Au-X demonstrated distinct properties with different coordinated *** radical behaviors have been investigated by EPR,UV-vis spectroscopy and cyclic voltammetry,additional structural information provided by structurally comparing related the precursor complexes given by X-ray ***-NHC-Au-I with SOMO-HOMO conversion(SHC)features a highly thermal decomposition temperature up to 305℃.Furthermore,the photostability of TTM-NHC-Au-I was found to be 75and 23 times greater than that of TTM-NHC-Au-Br and TTM-NHC-Au-Cl,*** findings provide valuable insights into the structural and electronic design principles governing the occurrence of SOMO-HOMO conversion in open-shell systems.

关键词： SOMO-HOMO conversion N-heterocyclic carbenes Aufbau and non-Aufbau Electronic structure Halogen atoms Radical

Comparative study of neuropeptide signaling systems in Hemiptera

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Insect Science 2023年第3期30卷 705-724页

作者： han Gao Yanxiao li hui zhang Suisui Wang Fan feng Jing Tang Bin li Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingChina

Numerous physiological processes in insects are tightly regulated by neuropeptides and their *** they form an ancient signaling system,there is still a great deal of variety in neuropeptides and their receptors among different species within the same *** and their receptors have been documented in many hemipteran insects,but the differences among them have been poorly *** grapevines worldwide are plagued by the bug Daktulosphaira vitifoliae(Hemiptera:Sternorrhyncha).Here,33 neuropeptide precursors and 48 putative neuropeptide G protein-coupled receptor(GPCR)genes were identified in *** expression profiles at the probe and feeding stages reflected potential regulatory roles in probe *** comparison,we found that the Releasing Hormone-Related Peptides(GnRHs)system of Sternorrhyncha was differentiated from those of the other 2 suborders in *** secondary losses of the adipokinetic hormone/corazoninrelated peptide receptor(ACP)and corazonin(CRZ)occurred during the evolution of ***,we discovered that the neuropeptide signaling systems of Sternorrhyncha were very different from those of Heteroptera and Auchenorrhyncha,which was consistent with Sternorrhyncha's phylogenetic position at the base of the *** research provides more knowledge on neuropeptide systems and sets the groundwork for the creation of novel *** management strategies that specifically target these signaling pathways.

关键词： D.vitifoliae GPCR Hemiptera neuropeptide

Cytotoxic Diarylheptanoids from Pericarps of Juglans Cathayensis Dode

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Chemical Research in Chinese Universities 2008年第4期24卷 427-429页

作者： li Yi-xiu RUAN han-li ZHOU Xue-feng zhang Yong-hui PI hui-fang WU Ji-zhou Faculty of Pharmaceutical Sciences Tongji Medical College of Huazhong University of Science and Technology Wuhan 430030 P R. China

A novel diarylheptanoid, named Jugcathanin（1）, along with two known diarylheptanoids（2,3）, were isolated from the fresh pericarps ofduglans Cathayensis Dode. A known triterpene（4） and a known aphthaoquinone（5） were also isolated from the plant. Their structures were elucidated on the basis of spectroscopic studies. All the compounds exhibited moderate cytotoxicities against human Hela, HepG2, and HL-60 cell lines.

关键词： duglans Cathayensis Dode Jugcathanin Antitumor activity