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Research in Astronomy and Astrophysics 2015年第8期15卷 1209-1239页

作者： Mao-Sheng Xiang Xiao-Wei Liu Hai-Bo Yuan Yang Huang Chun Wang Juan-Juan Ren Bing-Qiu chen ning-chen sun Hua-Wei Zhang Zhi-Ying Huo Alberto Rebassa-Mansergas Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University National Astronomical Observatories Chinese Academy of Sciences

Accurate measurements of stellar metallicity gradients in the radial and vertical directions of the disk and their temporal variations provide important constraints on the formation and evolution of the Milky Way disk. We use 297 042 main sequence turn-off stars selected from the LAMOST Spectroscopic Survey of the Galactic Anticenter（LSS-GAC） to determine the radial and vertical gradients of stellar metallicity,△[Fe/H]/△R and △[Fe/H]/△｜Z ｜ of the Milky Way disk in the direction of the anticenter. We determine ages of those turn-off stars by isochrone fitting and measure the temporal variations of metallicity gradients. We have carried out a detailed analysis of the selection effects resulting from the selection, observation and data reduction of LSS-GAC targets and the potential biases of a magnitude limited sample on the determinations of metallicity gradients. Our results show that the gradients, both in the radial and vertical directions, exhibit significant spatial and temporal variations. The radial gradients yielded by stars with the oldest ages（ 11 Gyr） are essentially zero at all heights from the disk midplane, while those given by younger stars are always negative. The vertical gradients deduced from stars with the oldest ages（ 11 Gyr）are negative and only show very weak variations with Galactocentric distance in the disk plane, R, while those yielded by younger stars show strong variations with *** being essentially flat at the earliest epochs of disk formation, the radial gradients steepen as age decreases, reaching a maximum（steepest） at age 7–8 Gyr, and then they flatten again. Similar temporal trends are also found for the vertical gradients. We infer that the assembly of the Milky Way disk may have experienced at least two distinct phases. The earlier phase is probably related to a slow, pressure-supported collapse of gas, when the gas settles down to the disk mainly in the vertical direction. In the later phase, there are significant radial flows

关键词： Galaxy: abundances—Galaxy: disk—Galaxy: evolution – Galaxy: formation—techniques: spectroscopic

On the metallicity gradients of the Galactic disk as revealed by LSS-GAC red clump stars

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Research in Astronomy and Astrophysics 2015年第8期15卷 1240-1263页

作者： Yang Huang Xiao-Wei Liu Hua-Wei Zhang Hai-Bo Yuan Mao-Sheng Xiang Bing-Qiu chen Juan-Juan Ren ning-chen sun Chun Wang Yong Zhang Yong-Hui Hou Yue-Fei Wang Ming Yang Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University Nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences

Using a sample of over 70 000 red clump（RC） stars with 5%–10% distance accuracy selected from the LAMOST Spectroscopic Survey of the Galactic Anti-center（LSS-GAC）, we study the radial and vertical gradients of the Galactic disk（s） mainly in the anti-center direction, covering a significant volume of the disk in the range of projected Galactocentric radius 7 ≤ RGC ≤ 14 kpc and height from the Galactic midplane 0 ≤ ｜Z ｜ ≤ 3 kpc. Our analysis shows that both the radial and vertical metallicity gradients are negative across much of the volume of the disk that is probed, and they exhibit significant spatial variations. Near the solar circle（7 ≤ RGC ≤ 11.5 kpc）, the radial gradient has a moderately steep, negative slope of-0.08 dex kpc-1near the midplane（｜Z ｜〈 0.1 kpc）, and the slope flattens with increasing ｜Z ｜. In the outer disk（11.5 〈 RGC ≤ 14 kpc）, the radial gradients have an essentially constant, much less steep slope of-0.01 dex kpc-1at all heights above the plane, suggesting that the outer disk may have experienced an evolutionary path different from that of the inner disk. The vertical gradients are found to flatten largely with increasing RGC. However, the vertical gradient of the lower disk（0 ≤ ｜Z ｜ ≤ 1 kpc）is found to flatten with RGC quicker than that of the upper disk（1 〈｜Z ｜ ≤ 3 kpc）.Our results should provide strong constraints on the theory of disk formation and evolution, as well as the underlying physical processes that shape the disk（e.g. gas flows,radial migration, and internal and external perturbations）.

关键词： Galaxy: abundances—Galaxy: disk—Galaxy: evolution—Galaxy: formation—techniques: spectroscopic

Galactic disk bulk motions as revealed by the LSS-GAC DR2

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Research in Astronomy and Astrophysics 2015年第8期15卷 1342-1363页

作者： ning-chen sun Xiao-Wei Liu Yang Huang Hai-Bo Yuan Mao-Sheng Xiang Hua-Wei Zhang Bing-Qiu chen Juan-Juan Ren Chun Wang Yong Zhang Yong-Hui Hou Yue-Fei Wang Ming Yang Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University Nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences

We report a detailed investigation of the bulk motions of the nearby Galactic stellar disk, based on three samples selected from the LSS-GAC DR2： a global sample containing 0.57 million FGK dwarfs out to ～2 kpc, a local subset of the global sample consisting of ～5400 stars within 150 pc, and an anti-center sample containing ～4400AFGK dwarfs and red clump stars within windows a few degrees wide centered on the Galactic Anti-center. The global sample is used to construct a three-dimensional map of bulk motions of the Galactic disk from the solar vicinity out to ～2 kpc with a spatial resolution of ～250 pc. Typical values of the radial and vertical components of bulk motion range from-15 km s-1to 15 km s-1; in contrast, the lag behind the circular motion dominates the azimuthal component by up to ～15 km s-1. The map reveals spatially coherent, kpc-scale stellar flows in the disk, with typical velocities of a few tens of km s-1. Bending- and breathing-mode perturbations are clearly visible,and vary smoothly across the disk plane. Our data also reveal higher-order perturbations, such as breaks and ripples, in the profiles of vertical motion versus height. From the local sample, we find that stars from different populations exhibit very different patterns of bulk motion. Finally, the anti-center sample reveals a number of peaks in stellar number density in the line-of-sight velocity versus distance distribution, with the nearer ones apparently related to the known moving groups. The ＂velocity bifurcation＂ reported by Liu et al. at Galactocentric radii 10–11 kpc is confirmed. However,just beyond this distance, our data also reveal a new triple-peaked structure.

关键词： Galaxy: disk-Galaxy: kinematics and dynamics-Galaxy: stellar content

The LAMOST spectroscopic survey of globular clusters in M31and *** and new identifications

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Research in Astronomy and Astrophysics 2015年第8期15卷 1392-1413页

作者： Bing-Qiu chen Xiao-Wei Liu Mao-Sheng Xiang Hai-Bo Yuan Yang Huang Zhi-Ying Huo ning-chen sun Chun Wang Juan-Juan Ren Hua-Wei Zhang Alberto Rebassa-Mansergas Ming Yang Yong Zhang Yong-Hui Hou Yue-Fei Wang Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences Nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences

We present a catalog of 908 objects observed with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST） in fields in the vicinity of M31 and M33, targeted as globular clusters（GCs） and candidates. The targets include known GCs and candidates selected from the literature, as well as new candidates selected from the Sloan Digital Sky Survey（SDSS）. Analysis shows that 356 of them are likely GCs with various confidence levels, while the remaining ones turn out to be background galaxies and quasars, stars and H II regions in M31 or foreground Galactic stars. The 356 likely GCs include 298 bona fide GCs and 26 candidates known in the literature. Three candidates, selected from the Revised Bologna Catalog of M31 GCs and candidates（RBC） and one possible cluster from Johnson et al., are confirmed to be bona fide clusters. We search for new GCs in the halo of the M31 among the new candidates selected from the SDSS photometry. Based on radial velocities yielded by LAMOST spectra and visual examination of the SDSS images, we find 28 objects, 5bona fide and 23 likely GCs. Among the five bona fide GCs, three have been recently discovered independently by others, and the remaining 25 are our new identifications,including two bona fide ones. The newly identified objects fall at projected distances ranging from 13 to 265 kpc from M31. Of the two newly discovered bona fide GCs,one is located near M33, probably a GC belonging to M33. The other bona fide GC falls on the Giant Stream with a projected distance of 78 kpc from M31. Of the 23 newly identified likely GCs, one has a projected distance of about 265 kpc from M31 and could be an intergalactic cluster.

关键词： galaxies: individual: M31 M33—galaxies: star clusters—galaxies: Local Group

On the LSP3 estimates of surface gravity for LAMOST-Kepler stars with asteroseismic measurements

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Research in Astronomy and Astrophysics 2016年第3期16卷 81-90页

作者： Juan-Juan Ren Xiao-Wei Liu Mao-Sheng Xiang Yang Huang Saskia Hekker Chun Wang Hai-Bo Yuan Alberto Rebassa-Mansergas Bing-Qiu chen ning-chen sun Hua-Wei Zhang Zhi-Ying Huo Wei Zhang Yong Zhang Yong-Hui Hou Yue-Fei Wang Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Max-Planck-Institut fiir Sonnensystemforschung Justus-von-Liebig-Weg 337077 GottingenGermany Stellar Astrophysics Centre Department of Physics and AstronomyAarhus UniversityNy Munkegade 1208000 Aarhus CDenmark Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China

Asteroseismology allows for deriving precise values of the surface gravity of stars. The accurate asteroseismic determinations now available for the large number of stars in the Kepler fields can be used to check and calibrate surface gravities that are currently being obtained spectroscopically for a huge number of stars targeted by large-scale spectroscopic surveys, such as the on-going Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） Galactic survey. The LAMOST spectral surveys have obtained a large number of stellar spectra in the Kepler fields. Stellar atmospheric parameters of those stars have been determined with the LAMOST Stellar Parameter Pipeline at Peking University （LSP3）, by template matching with the MILES empirical spectral library. In the current work, we compare surface gravities yielded by LSP3 with those of two asteroseismic samples-- the largest Kepler asteroseismic sample and the most accurate Kepler asteroseismic sample. We find that LSP3 surface gravities are in good agreement with asteroseismic values of Hekker et al., with a dispersion of -0.2 dex. Except for a few cases, asteroseismic surface gravities ofHuber et al. and LSP3 spectroscopic values agree for a wide range of surface gravities. However, some patterns in the differences can be identified upon close inspection. Potential ways to further improve the LSP3 spectroscopic estimation of stellar atmospheric parameters in the near future are briefly discussed. The effects of effective temperature and metallicity on asteroseismic determinations of surface gravities for giant stars are also discussed.

关键词： methods: data analysis -- stars: fundamental parameters -- stars: spectroscopic -- stars general -- stars: oscillations

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

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Neural Regeneration Research 2025年第6期20卷 1541-1554页

作者： Jinmei Ye Cong Duan Jiaxin Han Jinrong chen ning sun Yuan Li Tifei Yuan Daihui Peng Division of Mood Disorder Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Shanghai Key Laboratory of Psychotic Disorders Brain Health InstituteNational Center for Mental DisordersShanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina

In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.

关键词： biomarker cytokine exosomes inflammasome major depressive disorder microglia mitochondrial DNA mitochondrial dysfunction neuroinflammation Toll-like receptor

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米安色林治疗脑卒中后抑郁症

新药与临床 1996年第4期15卷 223-225页

作者：孟庆立卢世臣靳士立孙延强济宁市精神病防治院

目的：观察米安色林治疗由脑卒中所致抑郁症的疗效。方法：用米安色林６０ｍｇ／ｄ晚上１次顿服，疗程４ｗｋ，治疗３２例脑卒中后抑郁症。用全国统一的４级标准及ＨＡＭＤ，ＨＡＭＡ，ＣＧＩ，ＡＳＢＳ量表进行疗效和副作用评定。结果... 详细信息

目的：观察米安色林治疗由脑卒中所致抑郁症的疗效。方法：用米安色林６０ｍｇ／ｄ晚上１次顿服，疗程４ｗｋ，治疗３２例脑卒中后抑郁症。用全国统一的４级标准及ＨＡＭＤ，ＨＡＭＡ，ＣＧＩ，ＡＳＢＳ量表进行疗效和副作用评定。结果：在治疗ｗｋ２时已有明显疗效，ＨＡＭＤ，ＨＡＭＡ评分明显下降，疗效指数（ＥＩ）上升；ｗｋ４时已取得稳定疗效，总显效率为８４％；副作用有轻微头昏、嗜睡、口干、便秘、排尿困难及视物模糊；３例病人有一过性ＡＬＴ升高。结论：米安色林治疗脑卒中所致的抑郁症有良好效果，值得推广。

关键词：米安色林抑郁症脑血管意外药物疗法

An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells

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Nano-Micro Letters 2025年第2期17卷 372-375页

作者： Shuai Xu Youdi Zhang Yanna sun Pei cheng Zhaoyang Yao ning Li Long Ye Lijian Zuo Ke Gao Key Laboratory of Advanced Green Functional Materials College of ChemistryChangchun Normal UniversityChangchun 130032People’s Republic of China Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringShandong UniversityQingdao 266237People’s Republic of China College of Polymer Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China State Key Laboratory and Institute of Elemento‑Organic Chemistry Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer MaterialsRenewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071People’s Republic of China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640People’s Republic of China Tianjin Key Laboratory of Molecular Optoelectronic Sciences School of Materials Science and EngineeringTianjin UniversityTianjin 300350People’s Republic of China State Key Laboratory of Silicon Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China

Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer *** optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture *** approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs.

关键词： Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management

In situ polymerization of poly(3,4-ethylenedioxythiophene)protective layer towards stable zinc anode

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Nano Research 2025年第1期18卷 382-394页

作者： Debin Luo Peng Zhou Xiaowei Lv Panpan sun Xiaohua sun Hewei Zhao College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China Hubei Three Gorges Laboratory Yichang 443007China School of Chemistry Beihang UniversityBeijing 100191China

Aqueous zinc-ion devices are considered promising candidates for energy storage due to their high safety,low cost and relatively high energy ***,the dendrite growth,hydrogen evolution reaction(HER)and corrosion of the zinc anode significantly limit the development of Zn-ion ***,an inexpensive poly(3,4-ethylenedioxythiophene)(PEDOT)protective layer was constructed in situ on the Zn surface using electropolymerization to suppress dendrite growth and side reactions,thereby enhancing the reversibility of *** and theoretical calculations revealed that this hydrophilic protective layer promotes the desolvation process of hydrated Zn^(2+)and facilitates the transport of zinc ions,thus improving the thermodynamic and kinetic properties of Zn^(2+)deposition and inhibiting interfacial side ***,the optimized PEDOT@Zn symmetric battery exhibited a cycling stability exceeding 1250 h at 0.5 mA·cm^(-2)and 0.25 mAh·cm^(-2),with a significantly reduced overpotential(from 91.8 to 35 mV).With the assistance of the PEDOT protective layer,the PEDOT@Zn//Cu battery maintained approximately 99.5%Coulombic efficiency after 450 ***-situ scanning electron microscopy(SEM)and in situ optical microscopy characterizations further confirmed that the PEDOT protective layer can effectively suppress the growth of zinc ***,the Zn-ion capacitors assembled by the PEDOT@Zn and activated carbon also demonstrated outstanding cycling stability.

关键词： zinc-ion devices zinc anode poly(3 4-ethylenedioxythiophene)(PEDOT) dendrite desolvation process