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Number and Distribution of Fiducial Fibers in a Spectroscopic Survey Telescope

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Research in Astronomy and Astrophysics 2022年第2期22卷 108-117页

作者： shi-Peng Duan Zeng-Xiang zhou Jia-Le Zuo Meng-Tao Li Zhi-Gang Liu Hong-Zhuan Hu Jian-Ping Wang Xiang-qun Cui Yong Zhang Hao-Tong Zhang Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of ScienceNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

To date,the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)has been in operation for 12 *** improve the telescope's astronomical observation accuracy,the original open-loop fiber positioning system of LAMOST is in urgent need of *** upgrade plan is to install several fiber view cameras(FVCs)around primary mirror B to build a closed-loop feedback control *** FVCs are 20 m from the focal *** reduce a series of errors when the cameras detect the positions of the optical fibers,we designed fiducial fibers on the focal surface to be fiducial points for the *** the number of fiducial fibers can improve the detection accuracy of the FVC system,but it will also certainly reduce the number of fiber positioners that can be used for ***,the focus of this paper is how to achieve the quantity and distribution that meet the requirements of system *** this paper,we introduce the necessity of using fiducial fibers,propose a method for selecting their number and present several methods for assessing the uniformity of their ***,we implement particle swarm optimization to find the best distribution of fiducial fibers.

关键词： instrumentation detectors-techniques image processing-methods data analysis-telescopes

First-Principles Study of Hydrogen Impact on the Formation and Migration of Helium Interstitial Defects in hcp Titanium

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Chinese Physics Letters 2012年第1期29卷 82-85页

作者： LU Yong-Fang shi Li-qun DING Wei LONG Xing-Gui Institute of Modern Physics Fudan UniversityShanghai 200433 Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900

We present a first-principles study of the effects of hydrogen on helium behavior in hcp *** calculation indicates that the dissolved H atoms in hcp Ti change the formation energy of the interstitial He atom,but they do not change the energetically favorable occupying site of the He atom,i.e.,the tetrahedral site is more favorable than the octahedral *** impacts of H on the formation of interstitial He defects are directly related to the atomic environment around H atoms and their positions relative to interstitial He atoms as *** He diffusion,a tetrahedral interstitial He atom can more easily migrate along the indirect tetrahedron-octahedron-tetrahedron path than the direct path of *** a H atom exists in the first neighbor octahedral site from the He,the activation energy for He atom diffusion is 0.46eV,which is higher than that of the He atom diffusion in perfect crystal,0.41 *** the number of H atoms to two,He diffusion needs much higher activation *** suggests that the H atoms around interstitial He may impede the migration of interstitial He atom in hcp Ti.

关键词： diffusion activation Titanium

Severe Type of COVID-19:Pathogenesis,Warning Indicators and Treatment

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Chinese Journal of Integrative Medicine 2022年第1期28卷 3-11页

作者： shi Ke LIU Yao ZHANG qun RAN Chong-ping HOU Jie ZHANG Yi WANG Xian-bo Center of Integrative Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing(100015)China Department of Gastroenterology Dongzhimen HospitalBeijing University of Chinese MedicineBeijing(100007)China

Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2,is a major public health *** epidemic is unlikely to be contained until the global launch of safe and effective vaccines that could prevent serious illnesses and provide herd *** most patients have mild flu-like symptoms,some develop severe illnesses accompanied by multiple organ *** identification of pathophysiology and early warning biomarkers of a severe type of COVID-19 contribute to the treatment and prevention of serious ***,we review the pathophysiology,early warning indicators,and effective treatment of Chinese and Western Medicine for patients with a severe type of COVID-19.

关键词： coronavirus disease 2019 pathogenesis indicators treatment Chinese medicine

NUMERICAL SIMULATION OF UNSTEADY TURBULENT FLOW INDUCED BY TWO-DIMENSIONAL ELEVATOR CAR AND COUNTER WEIGHT SYSTEM

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Journal of Hydrodynamics 2007年第6期19卷 720-725页

作者： shi Li-qun LIU Ying-zheng JIN Si-yu CAO Zhao-min Power Machinery Engineering lab Key Lab of Education Ministry of China School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

A two-dimensional model of unsteady turbulent flow induced by high-speed elevator system was established in the present study. The research was focused on the instantaneous variation of the aerodynamic force on the car structure during traversing motion of the counter weight in the hoistway. A dynamic meshing method was employed to treat the multi-body motion system to avoid poor distortion of meshes. A comprehensive understanding of this significant aspect was obtained by varying the horizontal gap （δ =0.1m, 0.2m, and 0.3m） between the elevator car and the counter weight, and the moving speed （ U 0= 2m/s, 6m/s, and 10m/s） of the elevator system. A pulsed intensification of the aerodynamic force on the elevator car and subsequent appearance of large valley with negative aerodynamic force were clearly observed in the numerical results. In parameters studied （ δ =0.1m, U 0= 2m/s, 6m/s, 10m/s）, the peaked horizontal and vertical forces are respectively 7-11 and 4.3-5.65 times of that when the counter weight is far from the car. These results demonstrated the prominent influence of the traversing counter weight on aerodynamic force on the elevator car, which is of great significance to designers of high-speed elevator system.

关键词： high-speed elevator turbulent flow aerodynamic force Computational Fluid Dynamics (CFD)

Two new bufotoxins from the skin of Bufo bufo gargarizans

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Chinese Chemical Letters 2013年第8期24卷 731-733页

作者： Hai-Yan Li Lian-Zhu Zhang shi-Hui Wang Yue Deng Xiang-qun Jin Affiliated Hospital of Changchun University of Chinese Medicine College of Pharmaceutical Sciences Jilin University

Two new bufotoxins,tolocinobufagin-3-succinoylarginine ester and tolocinobufagin-3-hemisuberate, were isolated from the skin of Bufo bufo gargarizans ***-3-hemisuberate was also isolated from the natural source for th... 详细信息

关键词： Bufotoxins Bufo bufo gargarizans Tolocinobufagin-3-succinoylarginine Tolocinobufagin-3-hemisuberate

Epidemiological Survey of Hemoglobinopathies Based on Next-Generation Sequencing Platform in Hunan Province,China

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Biomedical and Environmental Sciences 2023年第2期36卷 127-134页

作者： XI Hui LIU Qin XIE Dong Hua zhou Xu TANG Wang Lan TANG De Guo ZENG Chun Yan WANG Qiong NIE Xing Hui PENG Jin Ping GAO Xiao Ya WU Hong Liang ZHANG Hao Qing QIU Li FENG Zong Hui WANG Shu Yuan zhou Shu Xiang HE Jun zhou shi Hao zhou Fa qun ZHENG Jun Qing WANG Shun Yao CHEN shi Ping ZHENG Zhi Fen MA Xiao Yuan FANG Jun qun LIANG Chang Biao WANG Hua NHC Key Laboratory of Birth Defect for Research and Prevention Hunan Provincial Maternal and Child Health Care HospitalChangsha 410028HunanChina Yongzhou Hospital for Maternal and Child Health Care Yongzhou 425000HunanChina Changde Hospital for Maternal and Child Health Care Changde 415099HunanChina Hengyang Hospital for Maternal and Child Health Care Hengyang 421009HunanChina Shaoyang Hospital for Maternal and Child Health Care Shaoyang 422001HunanChina Yiyang Hospital for Maternal and Child Health Care Yiyang 413099HunanChina Yueyang Hospital for Maternal and Child Health Care Yueyang 414021HunanChina Center of Prenatal Diagnosis Chenzhou No.1 People’s HospitalChenzhou 423099HunanChina Loudi Hospital for Maternal and Child Health Care Loudi 417599HunanChina Huaihua Hospital for Maternal and Child Health Care Huaihua 418099HunanChina Xiangtan Hospital for Maternal and Child Health Care Xiangtan 411104HunanChina Zhuzhou Hospital for Maternal and Child Health Care Zhuzhou 412008HunanChina Changsha Hospital for Maternal and Child Health Care Changsha 410007HunanChina Xiangxi Tujia and Miao Autonomous Prefecture Hospital for Maternal and Child Health Care Jishou 416000HunanChina Zhang Jiajie Centre for maternal and child health family planning services Zhangjiajie 427299HunanChina BGI Genomics BGI-ShenzhenShenzhen 518083GuangdongChina Clinical Laboratory of BGI Health BGI-ShenzhenShenzhen 518083GuangdongChina BGI-Wuhan Clinical Laboratories BGI-ShenzhenWuhan 430074HubeiChina SEBIA Representative Office Shanghai 200001China

Objective This study was aimed at investigating the carrier rate of,and molecular variation in,α-andβ-globin gene mutations in Hunan *** We recruited 25,946 individuals attending premarital screening from 42 districts and counties in all 14 cities of Hunan *** screening was performed,and molecular parameters were *** The overall carrier rate of thalassemia was 7.1%,including 4.83%forα-thalassemia,2.15%forβ-thalassemia,and 0.12%for bothα-andβ-*** highest carrier rate of thalassemia was in Yongzhou(14.57%).The most abundant genotype ofα-thalassemia andβ-thalassemia was-α^(3.7)/αα(50.23%)andβ^(IVS-Ⅱ-654)/β^(N)(28.23%),***α-globin mutations[CD108(ACC>AAC),CAP+29(G>C),Hb Agrinio and Hb Cervantes]and sixβ-globin mutations[CAP+8(C>T),IVS-Ⅱ-848(C>T),-56(G>C),beta nt-77(G>C),codon 20/21(-TGGA)and Hb Knossos]had not previously been identified in ***,this study provides the first report of the carrier rates of abnormal hemoglobin variants andα-globin triplication in Hunan Province,which were 0.49%and 1.99%,*** Our study demonstrates the high complexity and diversity of thalassemia gene mutations in the Hunan *** results should facilitate genetic counselling and the prevention of severe thalassemia in this region.

关键词： Thalassemia Carrier rate Molecular spectrum Abnormal hemoglobin variants α-globin triplication

Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data

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Petroleum Science 2024年第3期21卷 1632-1648页

作者： Jin-Xiong shi Xiang-Yuan Zhao Lian-Bo Zeng Yun-Zhao Zhang Zheng-Ping Zhu Shao-qun Dong Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education Yangtze UniversityWuhan4310HubeiChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Geosciences China University of Petroleum(Beijing)Beijing102249China Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065ShaanxiChina

Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage *** cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging ***,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ***,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data *** address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,*** MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input *** particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD *** evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM ***,the built MKFD model was applied in a blind well test,and a variable importance analysis was *** comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger *** MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.

关键词： Reservoir type identification Geophysical logging data Kernel Fisher discriminantanalysis Mixedkernel function Deep carbonates

Ethanol-assisted synthesis of a Ni single-atom catalyst with poriferous 3D framework for efficient cascade CO_(2)electroreduction

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Rare Metals 2024年第9期43卷 4612-4619页

作者： Feng Wu shi-Qi Wang Sebastian Kunze Xiao-Ping Gao Pei-qun Yin Yu-En Wu Division of Life Sciences and Medicine Department of EndocrinologySchool of Chemistry and Materials ScienceThe First Affiliated Hospital of USTCUniversity of Science and Technology of ChinaHefei 230026China Department of Chemistry Seoul National UniversitySeoul 08826South Korea School of Biomedical Engineering Anhui Medical UniversityHefei 230032China

The electroreduction of carbon dioxide to generate multicarbon products is significant for achieving a carbon-neutral ***,the selectivity for multi-carbon products faces several challenges,such as the intricate nature of the multistep hydrogenation processes,slow reaction kinetics and the bicarbonate precipitate issue caused by alkaline *** factors hinder the extensive utilization of this ***,we successfully developed and implemented a tandem electrolyzer cascade to separate and optimize the complex elementary reactions involved in the process of multi-carbon production.

关键词： reaction. synthesis catalyst

Impact of Smoke-Free Legislation on Acute Myocardial Infarction and Subtypes of Stroke Incidence in Shenzhen,China,2012-2016:An Interrupted Time Series Analysis

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Biomedical and Environmental Sciences 2023年第6期36卷 527-536页

作者： shi Yu Lin XIONG Jing Fan LIU Li qun ZHAO Zhi Guang WAN Xia PENG Ji Department of Epidemiology and Biostatistics Institute of Basic Medical SciencesChinese Academy of Medical Sciences&School of Basic MedicinePeking Union Medical CollegeBeijing 100005China Shenzhen Center for Chronic Disease Control Shenzhen 518001GuangdongChina

Objective This study assesses the impact of smoke-free legislation on the incidence rate for acute myocardial infarction(AMI)and stroke in *** Data on ischemic(n=72,945)and hemorrhagic(n=18,659)stroke and AMI(n=17,431)incidence covering about 12 million people in Shenzhen from 2012 to 2016 were *** and gradual changes in incidence rates were analyzed using segmented Poisson *** Following the smoke-free legislation,a 9%(95%CI:3%-15%)immediate reduction was observed in AMI incidence,especially in men(8%,95%CI:1%-14%)and in those aged 65 years and older(17%,95%CI:9%-25%).The gradual annual benefits were observed only in hemorrhagic and ischemic stroke incidence,with a 7%(95%CI:2%-11%)and 6%(95%CI:4%-8%)decrease per year,*** health effect extended gradually to the 50-64 age *** addition,neither the immediate nor gradual decrease in stroke and AMI incidence rates did not show statistical significance among the 35-49 age group(P>0.05).Conclusion Smoke-free legislation was enforced well in Shenzhen,which would generate good experiences for other cities to enact and enforce smoke-free *** study also provided more evidence of the health benefits of smoke-free laws on stroke and AMI.

关键词： Smoke-free legislation Second-hand smoke Tobacco Myocardial infarction Stroke Prevention