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Information from the Kinematics of F and G Stars in the Solar Neighborhood

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chinese Journal of Astronomy and Astrophysics 2002年第5期2卷 419-428页

作者： yu-qin chen, {3. zhao and Jian-Rong ShiNational astronomical observatories, chinese academy of sciences, beijing 100012 National astronomical observatories Chinese Academy of Sciences Beijing 100012

We have calculated the orbital parameters for 90 stars in chen et al. and updated the kinematic data for stars in Edvardsson et al. by using the accurate Hipparcos parallaxes and proper motions, and recalculated the α-element abundances in Edvardsson et al. in a way consistent with chen et al. The two sets of data are combined in a study of stellar populations and characteristics of F & G stars in the solar neighborhood. We confirm the result of chen et al. that a distinguishable group of stars may belong to the thick disk rather than the thin disk. The ages for the stars are determined using the theoretical isochrones of VandenBerg et al. The age-metallicity relation is investigated for different subgroups according to distance from the sun and galactic orbital parameters. It is found that a mixing of stars with different orbital parameters significantly affect the age-metallicity relation for the disk. Stars with orbits confined to the solar circle all have metallicities [Fe/H] > -0.3.irrespective of their distances from the sun or from the Galactic plane.

关键词： stars: kinematics - Galaxy: evolution - Galaxy: solar neighborhood

Equivalent Widths of 15 Extrasolar-Planet Host Stars

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chinese Journal of Astronomy and Astrophysics 2002年第4期2卷 377-390页

作者： gang zhao, yu-{3. chen and Hong-Mei QiuNational astronomical observatories, chinese academy of sciences, beijing 100012 National astronomical observatories CAS NAOC Beijing 100012 China

We present the equivalent widths of 15 extrasolar-planet host stars. These data were based on the high-resolution, high signal-to-noise ratio spectra obtained with the 2.16m telescope at Xinglong station. The error in the Xinglong equivalent width is estimated by a comparison of these data with those given in previous studies of common stars.

关键词： stars: planetary systems - stars: late-type

Metallicity calibration for solar type stars based on red spectra

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Research in Astronomy and Astrophysics 2011年第5期11卷 563-576页

作者： Jing-Kunzhao gangzhao {3.-qinchen A-LiLuo KeyLaboratoryofOpticalAstronomy NationalAstronomicalObservatoriesChineseAcademyofSciencesBeijing100012China

Based on a high resolution and high signal-to-noise ratio （S/N） spectral analysis of 90 solar-type stars, we have established several new metaUicity calibrations in the Tefr range [5600, 6500] K based on red spectra with the wavelength range of 560-880 nm. The new metallicity calibrations are applied to determine the metallicity of solar analogs selected from Sloan Digital Sky Survey （SDSS） spectra. There is a good consistent result with the adopted value presented in SDSS-DR7 and a small scatter of 0.26 dex for stars with S/N 〉 50 being obtained. This study provides a new reliable way to derive the metallicity for solar-like stars with low resolution spectra. In particular, our calibrations are useful for finding metal-rich stars, which are missing in the SEGUE Stellar Parameter Pipeline.

关键词： techniques: radial velocities - stars: temperatures - stars: abundances

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence of CKD in chinese adults

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Frontiers of Medicine 2024年第2期18卷 303-314页

作者： Yi Ding Xiaoli Xu Zhuojun Xin Qiuyu Cao Jiaojiao Huang Xianglin Wu Yanan Huo qin Wan Yingfen qin Ruying Hu Lixin Shi qing Su Xuefeng yu Li Yan Guijun qin Xulei Tang gang chen Min Xu Tiange Wang Zhiyun zhao Zhengnan Gao Guixia Wang Feixia Shen Zuojie Luo Li chen Qiang Li Zhen Ye Yinfei Zhang Chao Liu Youmin Wang Tao Yang Huacong Deng Lulu chen Tianshu Zeng Jiajun zhao Yiming Mu Shengli Wu yuhong chen Jieli Lu Weiqing Wang Guang Ning yu Xu yufang Bi Mian Li Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai National Clinical Research Center for Metabolic Diseases Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of ChinaShanghai Key Laboratory for Endocrine TumorState Key Laboratory of Medical GenomicsRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Jiangxi Provincial People’s Hospital Affiliated to Nanchang UniversityNanchang330000China Department of Endocrinology The Affiliated Hospital of Southwest Medical UniversityLuzhou646000China Department of Endocrinology The First Affiliated Hospital of Guangxi Medical UniversityNanning530000China Zhejiang Provincial Center for Disease Control and Prevention Hangzhou310000China Department of Endocrinology Affiliated Hospital of Guiyang Medical UniversityGuiyang550000China Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai200000China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430000China Sun Yat-sen Memorial Hospital Sun Yat-sen UniversityGuangzhou510000China Department of Endocrinology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450000China Department of Endocrinology The First Hospital of Lanzhou UniversityLanzhou730000China Fujian Provincial Hospital Fujian Medical UniversityFuzhou350000China Dalian Municipal Central Hospital Affiliated of Dalian Medical UniversityDalian116000China Department of Endocrinology The First Hospital of Jilin UniversityChangchun130000China Department of Endocrinology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou325000China Qilu Hospital of Shandong University Jinan250000China Department of Endocrinology The Second Affiliated Hospital of Harbin Medical UniversityHarbin150000China Department of Endocrinology Cen

Studies have found a U-shaped relationship between sleep duration and chronic kidney disease(CKD)risk,but limited research evaluated the association of reallocating excessive sleep to other behavior with *** included 10453. participants from the nationwide cohort of the Risk Evaluation of Cancers in chinese Diabetic Individuals:A Longitudinal Study,with self-reported time of daily-life *** isotemporal substitution models,we found that substituting 1 h of sleeping with sitting,walking,or moderate-to-vigorous physical activity was associated with a lower CKD ***-time physical activity displacement was associated with a greater prevalence reduction than occupational physical activity in working *** stratified analysis,a lower CKD prevalence related to substitution toward physical activity was found in long *** pronounced correlations were observed in long sleepers with diabetes than in those with prediabetes,and they benefited from other behavior substitutions toward a more active *** U-shaped association between sleep duration and CKD prevalence implied the potential effects of insufficient and excessive sleep on the kidneys,in which the pernicious link with oversleep could be reversed by time reallocation to physical *** divergence in the predicted effect on CKD following time reallocation to behavior of different domains and intensities and in subpopulations with diverse metabolic statuses underlined the importance of optimizing sleeping patterns and adjusting integral behavioral composition.

关键词： sleep physical activity chronic kidney disease isotemporal substitution behavioral pattern

Partitioning the Galactic halo with Gaussian Mixture Models

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Research in Astronomy and Astrophysics 2021年第5期21卷 274-286页

作者： Xi-Long Liang yu-qin chen Jing-Kun {3. gang {3. School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The Galactic halo is supposed to form from merging with nearby dwarf *** order to probe different components of the Galactic halo,we have applied the Gaussian Mixture Models method to a selected sample of metal poor stars with[Fe/H]3.4 and 5),one from the thick disk(group 6),one from the thin disk(group 8)and one from dwarf galaxies(group 7)by analyzing their distributions in the([M/H],[Mg/Fe]),(VR,V),(Zmax,eccentricity),(Energy,Lz)and([Mg/Mn],[Al/Fe])*** rest of the two groups are respectively caused by observational effect(group 9)and the cross section component(group 2)between the thin disk and the thick *** is found that in the extremely outer accreted halo(group 1),stars born in the Milky Way cannot be distinguished from those accreted from other galaxies either chemically or *** the intermediate metallicity of−1.6<[Fe/H]<−0.7 dex,the accreted halo is mainly composed of the Gaia-Enceladus-Sausage substructure(group 5),which can be easily distinguished from group 4(the in-situ halo group)in both chemical and kinematic *** stars of group 4 may come from the disk and some disk stars can be scattered to high orbits by resonant effects as shown in the Zmax versus Energy *** also displayed the spatial distribution of main components of the halo and the ratio of accreted components do not show clear relation to the Galactic radius.

关键词： Galaxy:abundances Galaxy:kinematics Galaxy:structure

淄博市供暖前后PM_(2.5)中多环芳烃及其衍生物污染特征、来源及健康风险

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环境科学 2024年第5期45卷 2558-2570页

作者：孙港立吴丽萍徐勃高玉宗赵雪艳姬亚芹杨文天津城建大学环境与市政工程学院天津300384 中国环境科学研究院北京100012 山东省淄博生态环境监测中心淄博255000 南开大学环境科学与工程学院天津300350

大气中的多环芳烃(PAHs)及其衍生物是影响环境和威胁人类健康的全球性问题.为了研究淄博市PM_(2.5)中PAHs及其衍生物的污染特征、来源和健康风险,于2020年11月5日至12月26日期间采集PM_(2.5)样品,使用气相色谱-质谱联用仪(GC-MS)分析PM_... 详细信息

大气中的多环芳烃(PAHs)及其衍生物是影响环境和威胁人类健康的全球性问题.为了研究淄博市PM_(2.5)中PAHs及其衍生物的污染特征、来源和健康风险,于2020年11月5日至12月26日期间采集PM_(2.5)样品,使用气相色谱-质谱联用仪(GC-MS)分析PM_(2.5)中的16种常规PAHs、9种NPAHs和5种OPAHs的浓度,利用特征比值法和PMF模型对其主要来源进行解析,并使用基于源解析结果的终生致癌风险模型(ILCR)评估了供暖前后PAHs及其衍生物对成年男女的健康风险.结果表明,采样期间淄博市PM_(2.5)中∑_(16)pPAHs、∑_(9)NPAHs和∑5OPAHs浓度均值分别为:(41.61±13.40)、(6.3.±5.70)和(53.20±53.47)ng·m^(−3.,供暖后3.PAHs浓度明显增加,分别为供暖前的1.3.、2.04和5.24倍.采样期间(Chr)、苯并[a]芘(BaP)和苯并[a]蒽(BaA)为pPAHs的优势组分,9-硝基蒽(9N-Ant)和2-硝基荧蒽+3.硝基荧蒽(2N-Flt+3.-Flt)为NPAHs的优势组分,蒽醌(ATQ)和苯并蒽酮(BZO)为OPAHs的优势组分.煤和生物质燃烧混合源以及二次生成是采暖后PM_(2.5)中PAHs及其衍生物增长的主要来源.采样期间BaP毒性当量浓度(TEQ)为14.5 ng·m^(−3.,供暖后TEQ明显增加,约为供暖前的1.2倍.淄博市PM_(2.5)中PAHs及其衍生物对成年男性(1.06×10^(−5))和女性(9.3.×10^(−6))均存在一定的潜在致癌风险.其中,汽油车、柴油车和煤炭/生物质排放的PAHs造成的健康风险更高.

关键词： PM_(2.5) 采暖季母体多环芳烃(pPAHs) 硝基多环芳烃(NPAHs) 含氧多环芳烃(OPAHs) 源解析健康风险

An Analysis of the Condensation Temperature of Elements of Extrasolar Planetary Systems

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chinese Journal of Astronomy and Astrophysics 2005年第6期5卷 619-626页

作者： Cong Huang gang zhao Hua-Wei Zhang yu-{3. chen Department of Astronomy Peking University Beijing 100871 National astronomical observatories Chinese Academy of Sciences Beijing 100012

Using high signal-to-noise ratio spectra of extrasolar planet-hosting stars, we obtained the atmospheric parameters, accurate metallicities and the differential abundance for 15 elements （C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Mn, Ni and Ba）. In a search for possible signatures of metal-rich material accreting onto the parent stars, we found that, for a given element, there is no significant trend of increasing [X/H] with increasing condensation temperature To. In our sample of planet-harboring stars, the volatile and refractory elements behave similarly, and we can not confirm if there exists any significant dependence on the condensation temperature Tc.

关键词： planetary systems - stars abundance - stars late-type

Automatic Normalization and Equivalent-Width Measurement of High-Resolution Stellar Spectra

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 689-696页

作者： Jing-Kun zhao gang zhao {3.-qin chen Jian-Rong Shi {3.-Juan Liu Ju-Yong Zhang National astronomical observatories Chinese Academy of Sciences Beijing 100012

It is well known that normalization, radial velocity correction and equivalent-width measurement of high-resolution stellar spectra are time-consuming work. In order to improve the efficiency we present an automatic method for these routines. The continuum is determined by fitting the ＇high points＇ in the spectrum. After continuum normalization, the program automatically searches for the position of the Ha line and obtains a rough radial velocity, then computes an accurate radial velocity by cross-correlation between the given spectrum and the solar spectrum. In this method, the equivalent-width is automatically measured using Gaussian fitting. A comparison between our results and those from traditional analysis shows that the typical error for equivalent width is around 3.8% in our method. Developing such automatic routines does not mean to replace the interactive reduction method： it is just for a quick extraction of information from the spectra, especially those obtained in large sky surveys.

关键词： techniques radial velocities - stars abundances

Incidence and prognosis of olfactory and gustatory dysfunctions related to SARS-CoV-2 Omicron strain infection in China:A national multicenter survey of 3.,566 individuals

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 113-120页

作者： Meng-Fan Liu Rui-Xia Ma Xian-Bao Cao Hua Zhang Shui-Hong Zhou Wei-Hong Jiang Yan Jiang Jing-Wu Sun qin-Tai Yang Xue-Zhong Li Ya-Nan Sun Li Shi Min Wang Xi-cheng Song Fu-Quan chen Xiao-Shu Zhang Hong-Quan Wei Shao-qing yu Dong-Dong Zhu Luo Ba Zhi-Wei Cao Xu-Ping Xiao Xin Wei Zhi-Hong Lin Feng-Hong chen Chun-Guang Shan Guang-Ke Wang Jing Ye Shen-Hong Qu Chang-qing zhao Zhen-Lin Wang Hua-Bin Li Feng Liu Xiao-Bo Cui Sheng-Nan Ye Zheng Liu yu Xu Xiao Cai Wei Huang Ru-Xin Zhang yu-Lin zhao Guo-Dong yu Guang-gang Shi Mei-Ping Lu Yang Shen yu-Tong zhao Jia-Hong Pei Shao-Bing Xie Long-gang yu Ye-Hai Liu Shao-Wei Gu yu-cheng Yang Lei cheng Jian-Feng liu Graduate School of beijing University of chinese Medicine BeijingChina Department of Otorhinolaryngology Head and Neck Surgery China-Japan Friendship HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First People's Hospital of YinchuanYinchuanChina Department of Otorhinolaryngology The First People's Hospital of Yunnan ProvinceKunmingChina Department of Otorhinolaryngology The First Affiliated Hospital of Xinjiang Medical UniversityUrumqiChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Xiangya Hospital Central South UniversityChangshaChina Department of Otorhinolaryngology Head and Neck Surgery The Affiliated Hospital of Qingdao UniversityQingdaoChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of USTCHefeiChina Department of Otorhinolaryngology Head and Neck Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Qilu Hospital of Shandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery The Second Affiliated Hospital of Harbin Medical UniversityHarbinChina Department of Otolaryngology The Second Hospital of Shandong UniversityShandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery Peking University People's HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery Yantai Yuhuangding HospitalQingdao UniversityYantaiChina Department of Otorhinolaryngology Head and Neck Surgery Xijing HospitalThe Fourth Military Medical UniversityXi'anChina Gansu Provincial Center for Disease Control and Prevention LanzhouChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of China Medical UniversityShenyangChina Department of Otorhinolaryngology Head and Neck Surgery Tongji Hospit

Objective:This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in ***:This study was conducted by 45 tertiary Grade-A hospitals in *** and offline questionnaire data were obtained from patients infected with COVID-19 between December 28,2022,and February 21,*** collected information included basic demographics,medical history,smoking and drinking history,vaccination history,changes in olfactory and gustatory functions before and after infection,and other postinfection symptoms,as well as the duration and improvement status of olfactory and gustatory ***:Complete questionnaires were obtained from 3.,566 *** overall incidence of olfactory and taste dysfunction was 67.75%.Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste *** received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such *** infection,the average olfactory and taste VAS scores were 8.41 and 8.51,respectively;after infection,they decreased to 3.69 and 4.29 and recovered to 5.83.and 6.55 by the time of the *** median duration of dysosmia and dysgeusia was 15 and 12 days,respectively,with 0.5%of patients having symptoms lasting for more than 28 *** overall self-reported improvement rate was 59.16%.Recovery was higher in males,never smokers,those who received two or three vaccine doses,and those that had never experienced dental health issues,or chronic accompanying ***:The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in *** and prognosis are influenced by several factors,including sex,SARS-CoV-2 vaccination,history of head-facial trauma,nasal and oral health status,smoking and drinking history,and the persistence of accompanying symptoms.

关键词： epidemiologic studies incidence olfactory disorders prognosis SARS-CoV-2 taste disorders