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A sodium laser guide star coupling efficiency measurement method

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Research in Astronomy and Astrophysics 2016年第9期16卷 95-100页

作者： Lu Feng Zhi-Xia Shen Suijian Xue Yang-Peng Li kai Jin Angel Otarola Yong Bo Jun-wei Zuo Qi Bian kai wei Jing-Yao Hu Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China The Institute of Optics and Electronics Chinese Academy of Sciences Chengdu 610209 China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China Thirty Meter Telescope Corporation Pasadena California USA

A large telescope＇s adaptive optics （AO） system requires one or more bright artificial laser guide stars to improve its sky coverage. The recent advent of a high power sodium laser is perfect for such application. However, besides the output power, other parameters of the laser also have a significant impact on the brightness of the generated sodium laser guide star, mostly in non-linear relationships. When tuning and optimizing these parameters it is necessary to tune based on a laser guide star generation performance metric. Although return photon fluxis widely used, variability of the atmosphere and sodium layer makes it difficult to compare results from different sites or even within a short time period for the same site. A new metric, coupling efficiency, is adopted in our field tests. In this paper, we will introduce our method for measuring the coupling efficiency of a 20W class pulse sodium laser for AO application during field tests that were conducted during 2013-2015.

关键词： instrumentation adaptive optics -- methods observational -- atmospheric effects

Initial suction drainage decreases severe postoperative complications after pancreatic trauma:A cohort study

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World Journal of Gastrointestinal Surgery 2023年第8期15卷 1652-1662页

作者： kai-wei Li kai Wang Yue-Peng Hu Chao Yang Yun-Xuan Deng Xin-Yu Wang Yu-Xiu Liu wei-Qin Li wei-wei Ding The First School of Clinical Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Critical Care Medicine Jinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210002Jiangsu ProvinceChina Division of Trauma and Surgical Intensive Care Unit Research Institute of General SurgeryJinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210002Jiangsu ProvinceChina Division of Data and Statistics Department of Critical Care MedicineJinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210002Jiangsu ProvinceChina

BACKGROUND Few studies have addressed the question of which drain types are more beneficial for patients with pancreatic trauma(PT).AIM To investigate whether sustained low negative pressure irrigation(NPI)suction drainage is superior to closed passive gravity(PG)drainage in PT *** PT patients who underwent pancreatic surgery were enrolled consecutively at a referral trauma center from January 2009 to October *** primary outcome was defined as the occurrence of severe complications(Clavien-Dindo grade≥Ⅲb).Multivariable logistic regression was used to model the primary outcome,and propensity score matching(PSM)was included in the regression-based sensitivity *** In this study,146 patients underwent initial PG drainage,and 50 underwent initial NPI suction *** the entire cohort,a multivariable logistic regression model showed that the adjusted risk for severe complications was decreased with NPI suction drainage[14/50(28.0%)vs 66/146(45.2%);odds ratio(OR),0.437;95%confidence interval(CI):0.203-0.940].After 1:1 PSM,44 matched pairs were *** proportion of each operative procedure performed for pancreatic injury-related and other intra-abdominal organ injury-related cases was comparable in the matched *** suction drainage still showed a lower risk for severe complications[11/44(25.0%)vs 21/44(47.7%);OR,0.365;95%CI:0.148-0.901].A forest plot revealed that NPI suction drainage was associated with a lower risk of Clavien-Dindo severity in most *** This study,based on one of the largest PT populations in a single high-volume center,revealed that initial NPI suction drainage could be recommended as a safe and effective alternative for managing complex PT patients.

关键词： Pancreatic trauma Drainage Postoperative complications Clavien-Dindo Propensity score matching

The environmental index of the rare earth elements in conodonts:Evidence from the Ordovician conodonts of the Huanghuachang Section,Yichang area

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Chinese Science Bulletin 2012年第4期57卷 349-359页

作者： CHEN XiaoHong ZHOU Lian wei kai WANG Jin LI ZhiHong Wuhan Institute of Geology and Mineral Resources Wuhan 430223China Geological Processes and Mineral Resources State Key Laboratory of China University of GeosciencesWuhan 430074China

High-resolution microanalysis was performed on conodonts collected from the Huanghuachang section in the Yichang area using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). This region is regarded as a standard section for the division and correlation of the Ordovician system in southern China. The results show that the values of (La/Yb)N and (La/Sm)N decrease, while the values of δCe increase as seawater deepens and energy decreases. As the sedimentary environment changes from shallow-water carbonate platform to platform margin to open continental shelf to shelf basin, rare earth element distribution curves gradually transform from a right inclined pattern to a flat pattern to a left inclined pattern and a hat-shaped pattern. The present work proves that the values and distributive patterns of rare earth elements in conodonts correspond with the sedimentary environment, and therefore provide reliable evidence for the application of rare earth element concentrations of biogenic phosphates such as conodonts for palaeoenvironmental reconstructions.

关键词：稀土元素宜昌地区牙形石奥陶系环境指标 LA-ICP-MS 证据黄花

Prognostic role of chromogranin A in ：astration-resistant prostate cancer： a meta-analysis

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Asian Journal of Andrology 2018年第6期20卷 561-566页

作者： Peng Hong Run-Qi Guo Gang Song kai-wei Yang Lei Zhang Xue-Song Li kai Zhang Li-Qun Zhou Department of Urology Peking University First Hospital and Institute of UrologyNational Research Centre for Genitourinary OncologyBeijing 100034China.These authors contributed equally to this work.

We aimed to investigate the prognostic value of chromogranin A （CgA） in castration-resistant prostate cancer （CRPC）. We conducted a systematic literature search of PubMed, Web of Science, and EMBASE for citations published prior to September 2017 that described CgA and CRPC and performed a standard meta-analysis on survival outcomes. Our meta-analysis included eight eligible studies with 686 patients. The results were as follows： progression-free survival （PFS） was associated with CgA level （hazard ratio [HR] = 2.47, 95% confidence interval [CI]： 1.47-4.14, P = 0.0006）; PFS was relative to CgA change （HR = 9.22, 95% Ch 3.03-28.05, P〈 0.0001）; and overall survival （OS） was relative to CgA level （HR = 1.47, 95% Ch 1.15-1.87, P= 0.002）. When we divided the patients into two groups according to therapy status, the result for OS relative to CgA level was an HR of 1.26 （95% CI： 1.09-1.45, P = 0.001） in the first-line hormonal therapy group, and an HR of 2.33 （95% Ch 1.40-3.89, P = 0.001） in the second-line hormonal therapy or chemotherapy group. This meta-analysis indicated that a high CgA level had a negative influence on OS and PFS in CRPC patients. In addition, CRPC patients with a rising CgA had a shorter PFS. Further studies are needed to verify the prognostic value of CgA in CRPC.

关键词： castration-resistant prostate cancer chromogranin A prognosis

Synthesis and Structure of Bis[2,6-bis(2-pyridylamino)pyridinium] Tetrachlorocadmiumate(II)

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Chinese Journal of Structural Chemistry 2006年第6期25卷 714-718页

作者： ZHANG Min XIE Yong-Shu wei kai-Ju LIU Qing-Liang PENG Shie-Ming Department of Chemistry University of Scienceand Technology of China i-lefei 230026 China Department of Chemistry National Taiwan University Taipei Taiwan

The title compound （H3tpda）2[CdCl4] （H2tpda = 2,6-bis（2-pyridylamino）pyridi-ne） was synthesized by the reaction of CdCl2 with H2tpda in methanol under acidic condition. Singlecrystal X-ray analysis reveals that the compound crystallizes in monoclinic, space group P21/n with a = 13.377（3）, b = 16.978（3）, c = 14.328（3） A, β = 94.75（3）°, V = 3243.1（11） A^3, Z = 4, De = 1.603 g/cm^3,μ = 1.042 mm^-1, F（000） = 1576, C30H28CdCl4N10, Mr = 782.82, T = 291（2） K, R = 0.0433 and wR = 0.0848 for observed 4554 reflections with I 〉 2σ（I）. The cadmium（Ⅱ） atom in the complex anion is tetrahedrally coordinated by four chlorine atoms, whereas, in each [H3tpda]＋ cation, one pyridyl nitrogen is protonated. A 3D network is formed by multiple intermolecular hydrogen bonds between the cations and anions as well as π-π interactions among the pyridyl rings.

关键词： crystal structure cadmium complex 3D network tripyridyldiamine

Laser-induced breakdown spectroscopy for the classification of wood materials using machine learning methods combined with feature selection

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Plasma Science and Technology 2021年第5期23卷 117-125页

作者： Xutai CUI Qianqian WANG kai wei Geer TENG Xiangjun XU School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081People's Republic of China Key Laboratory of Photonic Information Technology Ministry of Industry and Information TechnologyBeijing 100081People's Republic of China

In this paper,we explore whether a feature selection method can improve model performance by using some classical machine learning models,artificial neural network,k-nearest neighbor,partial least squares-discrimination analysis,random forest,and support vector machine(SVM),combined with the feature selection methods,distance correlation coefficient(DCC),important weight of linear discriminant analysis(IW-LDA),and Relief-F algorithms,to discriminate eight species of wood(African rosewood,Brazilian bubinga,elm,larch,Myanmar padauk,Pterocarpus erinaceus,poplar,and sycamore)based on the laser-induced breakdown spectroscopy(LIBS)*** spectral data are normalized by the maximum of line intensity and principal component analysis is applied to the exploratory data *** feature spectral lines are selected out based on the important weight assessed by DCC,IW-LDA,and *** models are built by using the different number of feature lines(sorted by their important weight)as *** relationship between the number of feature lines and the correct classification rate(CCR)of the model is *** CCRs of all models are improved by using a suitable feature *** highest CCR achieves(98.55...0.39)%when the SVM model is established from 86 feature lines selected by the IW-LDA *** result demonstrates that a suitable feature selection method can improve model recognition ability and reduce modeling time in the application of wood materials classification using LIBS.

关键词： laser-induced breakdown spectroscopy(LIBS) feature selection wood materials

Neural network analytic continuation for Monte Carlo:Improvement by statistical errors

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Chinese Physics B 2023年第7期32卷 156-170页

作者：孙恺伟王垡 International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

This study explores the use of neural network-based analytic continuation to extract spectra from Monte Carlo *** apply this technique to both synthetic and Monte Carlo-generated *** training sets for neural networks are carefully synthesized without“data leakage”.We find that the training set should match the input correlation functions in terms of statistical error properties,such as noise level,noise dependence on imaginary time,and imaginary time-displaced *** have developed a systematic method to synthesize such training *** improved algorithm outperforms the widely used maximum entropy method in highly noisy *** an example,our method successfully extracted the dynamic structure factor of the spin-1/2 Heisenberg chain from quantum Monte Carlo simulations.

关键词： neural network analytic continuation quantum Monte Carlo

Five-year results of refractive outcomes and visionrelated quality of life after SMILE for the correction of high myopia

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1365-1370页

作者： Min Lang kai-wei Cao Ting Liu Ying Zhu Jian Ye Department of Ophthalmology Daping HospitalArmy Medical UniversityChongqing 400042China

AIM:To evaluate the long-term visual,refractive outcomes and vision-related quality of life after small incision lenticule extraction(SMILE)for the correction of high ***:Thirty patients(60 eyes)with high myopia who underwent SMILE more than 5y were selected as the SMILE *** 30 high myopia patients(60 eyes)who had worn corrective spectacles for more than 5y were selected as the control *** SMILE group,the postoperative follow-up time were 3,6 mo,1 and *** distance visual acuity(UDVA),corrected distance visual acuity(CDVA),spherical equivalent(SE),and ocular axial length(AL)were *** Chinese version of the National Eye Institute Visual Function Questionnaire-25(CHI-NEI-VFQ-25)was used to evaluate the vision-related quality of life in the SMILE group and the control ***:In SMILE group,the mean preoperative SE was-7.29±0.87 D(range-6.00 to-9.125 D).At 5-year follow up,the efficacy index and safety index of SMILE were 1.09±0.18 and 1.19±0.12,*** years postoperatively,44 eyes(73%)obtained a visual acuity of 20/20 or *** were no eyes with CDVA loss of one or more Snellen ***-nine eyes(82%)and 57 eyes(95%)were within±0.50 and±1.00 D of attempted correction at 5-year follow-up,***-eight eyes(80%)had astigmatism<0.50 D at 5-year *** postoperative mean SE values at 3,6 mo,1,and 5y were 0.11±0.44,0.07±0.45,-0.02±0.41,and-0.15±0.46 D,*** significant change was observed in the ocular AL from before operation to 5y postoperatively(26.08±0.96 mm vs 26.01±0.94 mm,P=0.068).Compared to the control group,the SMILE group showed a significantly higher total score on the CHI-NEI-VFQ-25(90.14 vs 81.43,P<0.001).CONCLUSION:In the present study,in a long-term follow-up we demonstrate that correcting high myopia with SMILE is safe,effective,and ***-related quality of life after SMILE is better in the SMILE group than in the control group who wore corrective

关键词： small incision lenticule extraction high myopia long-term follow-up

ibliometric research on the development of climate change in the BRI regions

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Advances in Climate Change Research 2021年第2期12卷 254-262页

作者： TAN Xian-Chun ZHU kai-wei SUN Yu-Ling ZHAO Wan-Yu CHEN Fangc Institutes of Science and Development Chinese Academy of SciencesBeijing100190China School of Public Policy and Management University of Chinese Academy of SciencesBeijing100190China National Science Library Chinese Academy of SciencesBeijing100190China Department of Library Information and Archives Management University of Chinese Academy of ScienceBeijing100190China

Climate change is one of the great global *** clarify the research status of climate change in the Belt and Road Initiative(BRI)regions,the BRI countries can better deal with climate *** study aims to improve our understanding of the status and trends of researchon climate change in the BRI *** on keywords associated with the BRI and climate change,we undertake bibliometric research bycollecting 21,225 related SCI/SSCI articles published during *** and analysis revealed the topics and hotspots of research on BRI and climate *** findings are ***,although the number of published articles exhibited a rapidly growing trend,theirdistribution is extremely *** were mainly published by institutions from USA,UK,China,India,and Germany,while individualcontributions from most BRI countries was less than 1%of the publication ***,existing studies focused on climate change impactson BRI countries,in addition,climate mitigation and adaptation in BRI regions,especially the assessment of climate change risks and measuresand policies in response to climate change,was less watched in the ***,not all BRI regions have been examined by *** Africa,South Asia,and West Asia and North Africa are hotspots,while the Pacific and Central Asia are largely *** the future,BRI countries need to improve their research ability on climate change and more attention should be paid to the field of climate mitigation,especially on the assessment of climate change risks,measures,and policies,and BRI countries in the Oceania and Central Asia regions.

关键词： Belt and road initiative Climate change Development trends Bibliometrics