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Fast pulse sampling module for real-time neutron–gamma discrimination

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Nuclear Science and Techniques 2019年第5期30卷 130-137页

作者： Jia-Le cai Dao-Wu li Pei-lin wang Zhi-Ming Zhang xiao-hui li Bao-Tong feng Ting-Ting Hu Teng Tong wei zhou long wei Beijing Engineering Research Center of Radiographic Techniques and Equipment Institute of High Energy PhysicsChinese Academy of Sciences School of Nuclear Science and Technology University of Chinese Academy of Sciences

An adaptable and compact fast pulse sampling module was developed for the neutron–gamma discrimination. The developed module is well suited for low-cost and low-power consumption applications. It is based on the Domino Ring Sampler 4(DRS4) chip, which offers fast sampling speeds up to 5.12 giga samples per second(GSPS) to digitize pulses from front-end detectors. The high-resolution GSPS data is useful for obtaining precise real-time neutron–gamma discrimination results directly in this module. In this study, we have implemented real-time data analysis in a field programmable gate array. Real-time data analysis involves two aspects: digital waveform integral and digital pulse shape discrimination(PSD). It can significantly reduce the system dead time and data rate processed offline. Plastic scintillators(EJ-299-33), which have proven capable of PSD, were adopted as neutron detectors in the experiments. A photomultiplier tube(PMT)(model #XP2020) was coupled to one end of a detector to collect the output light from it. The pulse output from the anode of the PMT was directly passed onto the fast sampling module. The fast pulse sampling module was operated at 1 GSPS and 2 GSPS in these experiments, and the AmBe-241 source was used to examine the neutron–gamma discrimination quality. The PSD results with different sampling rates and energy thresholds were evaluated. The figure of merit(FOM) was used to describe the neutron–gamma discrimination quality. The best FOM value of 0.91 was obtained at 2 GSPS and 1 GSPS sampling rates with an energy threshold of 1.5 MeV_(ee)(electron equivalent).

关键词： Real time Neutron–gamma discrimination Domino Ring Sampler 4 Plastic scintillators

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 ${\bm~{Einstein~~Probe}}$

Inherited Genetic Susceptibility to Nonimmunosuppressed Epstein-Barr Virus-associated T/NK-cell Lymphoproliferative Diseases in chinese Patients

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Current Medical Science 2021年第3期41卷 482-490页

作者： Yu-qi GUAN ke-feng SHEN li YANG Hao-dong cai Mei-lan ZHANG Jia-chen wang xiao-lu long Jie XIONG Jia GU Pei-ling ZHANG Min xiao wei ZHANG Jian-feng zhou Department of Hematology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Epstein-Barr virus(EBV)T/NK-cell lymphoproliferative diseases are characterized by clonal expansion of EBV-infected T or NK cells,including chronic active EBV infection of T/NK-cell type(CAEBVT/NK),EBV-associated hemophagocytic lymphohistiocytosis(EBV HLH),extranodal NK/T-cell lymphoma of nasal type(ENKTL),and aggressive NK-cell leukemia(ANKL).However,the role of inherited genetic variants to EBV+T/NK-LPDs susceptibility is still unknown.A total of 171 nonimmunosuppressed patients with EBV T/NK-LPDs and 104 healthy donors were retrospectively collected and a targeted sequencing study covering 15 genes associated with lymphocyte cytotoxicity was *** 94 gene variants,mostly located in UNCI 3D,LYST,ITK,and PRF1 genes were detected,and mutations covered 28/50(56.00%)of CAEBV-T/NK,31/51(60.78%)of EBV HLH,13/28(46.42%)of ENKTL,and 13/48(27.09%)of *** mutations represented monoallelic and ***-year overall survival rate of patients with CAEBV-T/NK and EBV+HLH was significantly lower in patients with germline mutations than in those without germline mutations(P=0.0284,P=0.0137).Our study provided novel insights into understanding a spectrum of nonimmunosuppressed EBV*T/NK-LPDs with respect to genetic defects associated with lymphocyte cytotoxicity and reminded us that the gene sequencing may be an auxiliary test for diagnosis and risk stratification of EBV+T/NK-LPDs.

关键词： germline mutation EBV-associated T/NK-cell lymphoproliferative disease hemophagocytic lymphohistiocytosis primary immunodeficiencies lymphocyte cytotoxicity gene sequencing

Pre-conceptional and prenatal exposure to secondhand smoke and autism spectrum disorder:a national multi-center study in china

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World Journal of Pediatrics 2023年第8期19卷 761-769页

作者： li-Zi lin xiao-Xuan Ou xiao-ling Zhan Xin wang li cai Xiu-Hong li Jin Jing Guang-hui Dong Guangdong Provincial Engineering Technology Research Center of Environmental Pollution and Health Risk Assessment Department of Occupational and Environmental HealthSchool of Public HealthSun Yat-Sen University74 Zhongshan 2nd RoadYuexiu DistrictGuangzhou510080China Department of Maternal and child Health School of Public HealthSun Yat-Sen University74 Zhongshan 2Nd RoadYuexiu DistrictGuangzhou510080China

Background Despite extensive research evaluating the association between prenatal exposure to secondhand smoke(SHS)and the development of autism spectrum disorders(ASD),no study has investigated the association by considering the pre-conceptional *** study aimed to investigate the associations of pre-conceptional and prenatal SHS exposure and the development of ASD among *** In this cross-sectional study,parents of 6049 toddlers aged 16–30 months were recruited from 7 tertiary hospitals,21 communities,and 7 kindergartens located in seven cities in six provinces from five geographical regions of *** analyzed the associations of SHS exposure and the odds of ASD among toddlers in different exposure windows(pre-conceptional and/or prenatal periods).Data were analyzed from November 2021 to January *** Among the 6049 toddlers included in the analysis[22.7(4.1)months;44.8%girls],71 were identified and diagnosed with *** with the unexposed toddlers,toddlers with pre-conceptional SHS exposure had higher odds of ASD(OR 2.30,95%CI 1.36–3.84),while we observed a non-significantly positive association regarding prenatal SHS *** considering both pre-conceptional and prenatal periods,toddlers who were continuously exposed to SHS during these two periods had higher odds than those without SHS exposure(OR 2.32,95%CI 1.24–4.14).Conclusion We reported positive SHS–ASD associations when exposed during the pre-conceptional period and continuously exposed during pre-conceptional and prenatal periods,emphasizing the critical window of pre-conception for targeted intervention on smoking.

关键词： Autism spectrum disorder china Epidemiology Pre-conception Secondhand smoke

Association between body mass index and the risk of bleeding in elderly patients with non-valvular atrial fibrillation taking dabigatran:a cohort study

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Journal of Geriatric Cardiology 2020年第4期17卷 193-201页

作者： Ming-hui li li-Hua HU Yu-Rong XIONG Yu YU wei zhou Tao wang ling-Juan ZHU Xi liU hui-hui BAO xiao-Shu CHENG Department of Cardiovascular Medicine the Second Affiliated Hospital of Nanchang UniversityJiangxiChina Center for Prevention and Treatment of Cardiovascular Diseases the Second Affiliated Hospital of Nanchang UniversityJiangxiChina Center of Cardiovascular Inner Mongolia People’s HospitalHohhotInner MongoliaChina

Background Uncertainty remains regarding the association between body mass index(BMI)and the risk of bleeding in patients with non-valvular atrial fibrillation(NVAF).We aimed to investigate the association between BMI and the risk of bleeding in elderly NVAF patients taking *** A total of 509 elderly NVAF patients,who were being treated at twelve centers in china from February 2015 to December 2017 and taking dabigatran,were *** exposure and outcome variables were BMI at baseline and bleeding events within the subsequent six months,*** proportional hazards regression analysis was used to evaluate the association between BMI and the risk of ***,the Cox proportional hazards regression with cubic spline functions and smooth curve fitting was *** During the six-month follow-up,50 participants experienced *** 1 kg/m^2 increase in BMI was associated with a 12%increased risk of bleeding(P=0.021).Compared to those with BMI values in Tertile 1(25.3 kg/m^2)were 2.71(95%CI:1.02–7.17)and 3.5(95%CI:1.21–8.70),*** Ptrend-value was significant in all *** adjusted smooth curve showed a linear association between BMI and *** of the stratified variables showed significant effect modification on the association between BMI and bleeding(Pinteraction>0.05).Conclusions BMI was significantly and positively associated with the risk of bleeding in elderly NVAF patients treated with dabigatran.

关键词： Atrial fibrillation Bleeding Body mass index Dabigatran

Comparing successful gene knock-in efficiencies of CRISPR/Cas9 with ZFNs and TALENs gene editing systems in bovine and dairy goat fetal fibroblasts

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Journal of Integrative Agriculture 2018年第2期17卷 406-414页

作者： liU hui liU Chang ZHAO Yu-hang HAN Xue-jie zhou Zheng-wei wang Chen li Rong-feng li Xue-ling State key Laboratory of Reproductive Regulation & Breeding of Grassland livestocks Inner Mongolia University Research Center for Laboratory Animal Science Inner Mongolia University State key Laboratories of Reproductive Medicine Nanjing Medical University Jiangsu key Laboratory of Xenotransplantation Nanjing Medical University

This study aimed to compare the efficiencies of clustered regulatory interspaced short palindromic repeat（CRISPR）/Cas9-mediated gene knock-ins with zinc finger nucleases（ZFNs） and transcription activator-like effector nucleases（TALENs） in bovine and dairy goat fetal fibroblasts. To test the knock-in efficiency, a set of ZFNs and CRISPR/Cas9 plasmids were designed to edit the bovine myostatin（MSTN） gene at exon 2, while a set of TALENs and CRISPR/Cas9 plasmids were designed for editing the dairy goat β-casein gene at exon 2. Donor plasmids utilizing the ZFNs, TALENs, and CRISPR/Cas9 cutting sites were constructed in theGFP-PGK-Neo R plasmid background, including a 5′ and 3′ homologous arm flanking the genes humanized Fat-1（h Fat-1） or enhanced green fluorescent protein（eGFP）. Subsequently, the ZFNs, TALENs, or CRISPR/Cas9 and thehFat-1 or eGFP plasmids were co-transfected by electroporation into bovine and dairy goat fetal fibroblasts. After G418（Geneticin） selection, single cells were obtained by mouth pipetting, flow cytometry or a cell shove. The gene knock-in events were screened by PCR across the homologous arms. The results showed that in bovine fetal fibrobalsts, the efficiencies of ZFNs-mediated eGFP andhFat-1 gene knock-ins were 13.68 and 0%, respectively. The efficiencies of CRISPR/Cas9-mediated eGFP andhFat-1 gene knock-ins were 77.02 and 79.01%, respectively. The eGFP gene knock-in efficiency using CRISPR/Cas9 was about 5.6 times higher than when using the ZFNs gene editing system. Additionally, thehFat-1 gene knock-in was only obtained when using the CRISPR/Cas9 system. The difference of knockin efficiencies between the ZFNs and CRISPR/Cas9 systems were extremely significant（P〈0.01）. In the dairy goat fetal fibroblasts, the efficiencies of TALENs-mediated eGFP andhFat-1 gene knock-ins were 32.35 and 26.47%, respectively. Theefficiencies of eGFP and hFat-1 gene knock-ins using CRISPR/Cas9 were 70.37 and 74.29%, respectively. The knock-in efficiencies diff

关键词： myostatin(MSTN) β-casein(CSN2) bovine fetal fibroblasts CRISPR/Cas9 dairy goat fetal fibroblasts eGFP hFat-1 knock-in mutation efficiency TALENs ZFNs

Co-infection of SARS-COV-2 and Influenza A Virus:A Case Series and Fast Review

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Current Medical Science 2021年第1期41卷 51-57页

作者： Xuan XIANG Zi-hao wang lin-lin YE Xin-liang HE xiao-shan wei Yan-ling MA hui li long CHEN xiao-rong wang Qiong zhou Department of Respiratory and Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Coronavirus disease 2019(COVID-19)occurs in the influenza season and has become a global *** present study aimed to examine severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)co-infection with influenza A virus(IAV)in an attempt to provide clues for the antiviral interventions of co-infected *** described two patients who were co-infected with SARS-CoV-2 and IAV treated at Wuhan Union Hospital,*** addition,we performed a review in PubMed,Web of Science and CNKI(from January 1 up to November 1,2020)with combinations of the following key words:“COVID-19,SARS-COV-2,influenza A and co-infection”.A total of 28 co-infected patients were enrolled in the *** the 28 patients,the median age was 54.5 years(IQR,34.25–67.5)and 14 cases(50.0%)were classified as severe *** most common symptoms were fever(85.71%),cough(82.14%)and dyspnea(60.71%).Sixteen patients had lymphocytopenia on admission and 23 patients exhibited abnormal radiological *** median time from symptom onset to hospital admission was 4 days(IQR,3–6),and the median time of hospital stay was 14 days(IQR,8.5–16.75).In conclusion,patients with SARSCOV-2 and IAV co-infection were similar to those infected with SARS-COV-2 alone in symptoms and radiological ***-COV-2 co-infection with IAV could lead to more severe clinical condition but did not experience longer hospital stay compared with patients infected with SARSCOV-2 alone.

关键词： co-infection COVID-19 influenza A SARS-COV-2

chinese Herbal Medicine Combined with Entecavir for HBeAg Positive Chronic Hepatitis B:Study Protocol for a Multi-Center,Double-Blind Randomized-Controlled Trial

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chinese Journal of Integrative Medicine 2018年第9期24卷 653-660页

作者： YE Yong-an li xiao-ke zhou Da-qiao chi xiao-ling li Qin wang li LU Bing-jiu MAO De-wen WU Qi-kai wang Xian-bo ZHANG Ming-xiang XUE Jing-dong li Yong LU wei GUO Jian-chun JIANG feng ZHANG Xin-wei DU Hong-bo YANG Xian-zhao GUO hui GAN Da-nan li Zhi-guo Institute of liver Diseases Beijing University of Chinese MedicineDongzhimen Hospital affiliated to Beijing University of Chinese Medicine Department of Hepatology Shenzhen Traditional Chinese Medicine Hospital Department of Hepatology Guangdong Hospital of Traditional Chinese Medicine Department of Hepatology Mengchao Hepatobiliary Hospital of Fujian Medical University Department of Hepatology Public Health Clinical Center of Chengdu Department of Hepatology Liaoning Hospital of Traditional Chinese Medicine Department of Hepatology the First Affiliated Hospital of Guangxi University of Chinese Medicine Department of Hepatology the Third People's Hospital of Shenzhen Department of Hepatology Beijing Ditan Hospital Department of Hepatology the Sixth People's Hospital of Shenyang Department of Hepatology Shaanxi Hospital of Traditional Chinese Medicine Department of Hepatology Shandong Hospital of Traditional Chinese Medicine Department of Hepatology the Second People's Hospital of Tianjin Department of Hepatology Xixi Hospital of Hangzhou Department of Hepatology 302 Military Hospital of China Department of Hepatology the First Teaching Hospital of Tianjin University of Traditional Chinese Medicine

Background： The domestic prevalence of chronic hepatitis B （CHB） in china is 7.18% in 2006, imposing great societal healthcare burdens. Nucleot（s）ide analogues （NUCs） anti-hepatitis B virus （HBV） therapies are widely applied despite the relatively low rate of seroconversion and high risk of drug-resistant mutation. More effective treatments for CHB deserve further explorations. Combined therapy of NUCs plus chinese herbal medicine （CHM） is widely accepted in china, which is recognized as a prospective alternative approach. The study was primarily designed to confirm the hypothesis that Tiaogan-Yipi Granule （调肝益脾颗粒, TGYP） or Tiaogan-Jianpi-Jiedu Granule （调肝健脾解毒颗粒, TGJPJD） plus entecavir tablet （ETV） was superior over ETV monotherapy in enhancing HBeAg loss rate. Methods： The study was a nationwide, large-scale, multi-center, double-blind, randomized, placebo-controlled trial with a designed duration of 108 weeks. A total of 16 hospitals and 596 eligible chinese HBeAg positive CHB patients were enrolled from November 2012 to September 2013 and randomly allocated into 2 groups in 1：1 ratio via central randomization system： experimental group （EG） and control group （CG）. Subjects in EG received CM formulae （TGYP or TGJPJD, 50 g per dose, twice daily） plus ETV tablet （or ETV placebo） 0.5 mg per day in the first 24 weeks （stage 1）, and CHM granule plus ETV tablet （0.5 mg per day） from week 25 to 108 （stage 2）. Subjects in CG received CHM Granule placebo plus E＇IV tablet （0.5 mg per day） for 108 weeks throughout the trial. The assessments of primary outcomes （HBV serum markers and HBV-DNA） were conducted by a third-party College of American Pathologists （CAP） qualified laboratory. Adverse effects were observed in the hospitals of recruitment. Discussion： The study was designed to compare the curative effect of CM plus E＇IV and ETV monotherapy in respect of HBeAg loss, which is recognized by the European Association for the Study of the liver as ＂a valuable endpoint＂. We be

关键词： chronic hepatitis B chinese herbal medicine Tiaogan-Jianpi-Jiedu Granule Tiaogan-Yipi Granule protocol randomized-controlled trial

An in-depth Exploration of LAMOST Unknown Spectra Based on Density Clustering

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Research in Astronomy and Astrophysics 2023年第5期23卷 52-65页

作者： Hai-feng Yang xiao-Na Yin Jiang-hui cai Yu-Qing Yang A-li Luo Zhong-Rui Bai li-Chan zhou Xu-Jun Zhao Ya-ling Xun Shanxi key Laboratory of Big Data Analysis and Parallel Computing Taiyuan University of Science and TechnologyTaiyuan 030024China School of Computer Science and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China School of Computer Science and Technology North University of ChinaTaiyuan 030051China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Large sky Area Multi-Object fiber Spectroscopic Telescope(LAMOST) has completed the observation of nearly 20 million celestial objects,including a class of spectra labeled “Unknown.” Besides low signal-to-noise ratio,these spectra often show some anomalous features that do not work well with current *** this paper,a total of 637,889 “Unknown” spectra from LAMOST DR5 are selected,and an unsupervised-based analytical framework of “Unknown” spectra named SA-Frame(Spectra Analysis-Frame) is provided to explore their origins from different *** SA-Frame is composed of three parts:NAPC-Spec clustering,characterization and origin ***,NAPC-Spec(Nonparametric density clustering algorithm for spectra) characterizes different features in the “unknown” spectrum by adjusting the influence space and divergence distance to minimize the effects of noise and high dimensionality,resulting in 13 ***,characteristic extraction and representation of clustering results are carried out based on spectral lines and continuum,where these 13 types are characterized as regular spectra with low S/Ns,splicing problems,suspected galactic emission signals,contamination from city light and un-gregarious type ***,a preliminary analysis of their origins is made from the characteristics of the observational targets,contamination from the sky,and the working status of the *** results would be valuable for improving the overall data quality of large-scale spectral surveys.

关键词： methods data analysis-surveys-techniques spectroscopic-site testing-methods analytical