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Pre-LOI trajectory maneuvers of the CHANG'E-2 libration point mission

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Science china(Information Sciences) 2012年第6期55卷 1249-1258页

作者： WU WeiRen 1,LIU Yong 2,3,LIU Lei 2,3,ZHOU JianLiang 3,TANG GeShi 2,3 & CHEN YongZhi 3 1 Chinese Lunar Exploration and Space Project center,beijing 100037,china 2 Science and Technology on Aerospace Flight Dynamics Laboratory,beijing 100094,china 3 beijing Aerospace control center,beijing 100094,china 1. Chinese Lunar Exploration and Space Project center Beijing 100037 China2. Science and Technology on Aerospace Flight Dynamics Laboratory Beijing 100094 China3. Beijing Aerospace Control Center Beijing 100094 China

This paper addresses pre-LOI (before Lissajous orbit insertion) trajectory maneuvers for the libration point mission of CHANG'E-2,which is the first Chinese satellite to fly to the Sun-Earth L2 libration point and the first satellite ever to fly to the L2 point from lunar ***,a transfer trajectory for the mission is designed based on InterPlanetary Superhighway theory under the constraint of the remaining propellant,TT&C (telemetry,track and command) and sunlight *** effects of trajectory maneuver errors on the mission are also ***,based on the analysis results,the article investigates the trajectory maneuver schemes for the lunar escape and transfer trajectory maneuvers employing mathematical models and operational *** mission status based on our maneuver schemes is then presented,and the results of control operation and corresponding analysis are provided in ***,the future trajectory maneuver in the Lissajous orbit is *** to the analysis of the CHANG'E-2 TT&C data,the trajectory maneuver schemes proposed in the article work properly and efficiently.

关键词： CHANG’E-2 libration point trajectory maneuver escape trajectory transfer trajectory

Meta-analysis of the relationship between Epstein-Barr virus infection and clinicopathological features of patients with gastric carcinoma

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Science china(Life Sciences) 2010年第4期53卷 524-530页

作者： LI ShuYing1,2, DU HaiJun3, WANG Zhan3, ZHOU Ling3, ZHAO XiaoYu1 & ZENG Yi3 1 College of Life Sciences, Hebei University, Baoding 071002, china 2 Department of Pathogenic Biology, Faculty of Biological Science, North china Coal Medical College, Tangshan 063000, china 3 National Institute for Viral disease control and prevention, Chinese center for disease control and prevention (Chinese CDC), State Key Laboratory for Infectious disease prevention and control (SKLID), beijing 100052, china 1. College of Life Sciences Hebei University Baoding 071002 China2. Department of Pathogenic Biology Faculty of Biological Science North China Coal Medical College Tangshan 063000 China3. National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention (Chinese CDC) State Key Laboratory for Infectious Disease Prevention and Control (SKLID) Beijing 100052 China

Epstein-Barr virus (EBV) infection has been causally associated with occurrence of many malignant neoplasms. EBV-encoded small RNAs (EBERs) have been detected from about 10% of gastric carcinoma tissue cells, suggesting that EBV infection is associated with the development of gastric carcinoma. The present study pooled the data from the papers concerning EBV-related gastric cancers and performed a meta-analysis of 22 research papers. Among these papers, a total of 5475 cases with gastric cancer were enrolled, of whom 411 cases were found EBV-positive, with the EBV-positive rate being 7.5%. Among the EBV-positive gastric cancer cases, the detection rate was 11.1% in males and 3.0% in females. Compared with EBV-negative gastric cancer, EBV-positive gastric cancer had less lymph node metastasis. Based on the histological typing, of the EBV-positive gastric cancers, the diffuse type was 8.1%, and intestinal type was 8.0%. The examined specimen types included stored paraffin blocks and fresh surgically removed specimens, their EBV positive rates were 7.9% and 6.5% respectively. In terms of geographical distribution, the detection rate of EBV-positive gastric cancer was 9.4% in America, 6.1% in Asia and 9.1% in Europe. Meta-analysis showed that EBV infection occurred only in gastric cancer tissue cells and was significantly associated with the patients’ gender, lymph node metastases, and the location where tumor tissue generated and geographical distribution (P0.05). These results suggested that EBV-positive gastric cancer has distinct clinicopathological features.

关键词： Epstein-Barr virus gastric carcinoma meta-analysis in situ hybridization

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中国阿尔茨海默病蓝皮书(精简版)

中华医学杂志 2024年第29期104卷 2701-2727页

作者：首都医科大学宣武医院国家神经疾病医学中心中国疾病预防控制中心慢性非传染性疾病预防控制中心国家卫生健康委能力建设和继续教育中心中国人口与发展研究中心《中国阿尔茨海默病蓝皮书》项目组首都医科大学宣武医院国家神经疾病医学中心中国疾病预防控制中心慢性非传染性疾病预防控制中心国家卫生健康委能力建设和继续教育中心中国人口与发展研究中心《中国阿尔茨海默病蓝皮书》项目组

随着中国人口老龄化程度不断加重, 阿尔茨海默病(AD)在我国的患病率和死亡率均不断上升, 已成为严重危害人民群众健康和影响社会可持续发展的重大疾病之一。为响应健康中国行动, 提高国民健康水平, 促进健康发展, 首都医科大学宣武医院... 详细信息

随着中国人口老龄化程度不断加重, 阿尔茨海默病(AD)在我国的患病率和死亡率均不断上升, 已成为严重危害人民群众健康和影响社会可持续发展的重大疾病之一。为响应健康中国行动, 提高国民健康水平, 促进健康发展, 首都医科大学宣武医院国家神经疾病医学中心、中国疾病预防控制中心慢性非传染性疾病预防控制中心、国家卫生健康委能力建设和继续教育中心、中国人口与发展研究中心等单位专家和学者联合编写《中国阿尔茨海默病蓝皮书(精简版)》(简称蓝皮书)。蓝皮书系统回顾了目前中国AD及其他认知障碍疾病的流行病学特征、诊疗现状、防治管理等情况, 旨在为人群AD疾病预防提供依据、为疾病规范化诊疗提供支持、为政府制定相关卫生政策提供参考。蓝皮书主要包括AD及其他认知障碍疾病的以下内容:(1)流行病学特征;(2)经济负担;(3)影响因素;(4)中国脑认知健康指数;(5)诊断现状;(6)治疗现状;(7)认知障碍诊疗中心建设;(8)社区防治;(9)AD患者的照料;(10)防治的公共卫生资源。

关键词：阿尔茨海默病流行病学诊断现状治疗现状社区防治照料负担

Molecular evolution of influenza A (H3N2) viruses cir-culated in Fujian Province, china during the 1996-2004 period

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Science china(Life Sciences) 2008年第4期51卷 373-380页

作者： XIU WenQiong, WEN YuWei, SHEN XiaoNa, XIE JianFeng, YANG ShiQin, WU BingShan & WANG MeiAi Fujian center for disease control & prevention, Fuzhou 350001, china Fujian center for disease control & prevention Fuzhou 350001 China

We studied the genetic and epidemic characteristics of influenza A (H3N2) viruses circulated in human in Fujian Province, south of china from 1996 to 2004. Phylogenetic analysis was carried out for genes encoding hemagglutinin1 (HA1) of influenza A virus (14 new and 11 previously reported reference se-quences). Our studies revealed that in the 8 flu seasons, the mutations of HA1 genes occurred from time to time, which were responsible for about four times of antigenic drift of influenza H3N2 viruses in Fujian, china. The data demonstrated that amino acid changes were limited to some key codons at or near antibody binding sites A through E on the HA1 molecule. The changes at the antibody binding site B or A or sialic acid receptor binding site 226 were critical for antigenic drift. But the antigenic sites might change and the key codons for antigenic drift might change as influenza viruses evolve. It seems important to monitor new H3 isolates for mutations in the positively selected codons of HA1 gene in south of Asia.

关键词： Influenza virus H3N2 hemagglutinin phylogenetic analysis drift key codons

Secreted Protein HP1286 of Helicobacter pylori Strain 26695 Induces Apoptosis of AGS Cells

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Biomedical and Environmental Sciences 2012年第6期25卷 614-619页

作者： LI Jing 1,2, , MENG Fan Liang 1,2, , HE Li Hua 1,2 , and ZHANG Jian Zhong 1,2, 1. National Institute for Communicable disease control and prevention, Chinese center for disease control and prevention, beijing 102206, china 2. State Key Laboratory for Infectious disease prevention and control, Chinese center for disease control and prevention, beijing 102206, china [a] National Institute for Communicable disease control and prevention Chinese Center for Disease Control and Prevention Beijing 102206 China [b] State Key Laboratory for Infectious disease prevention and control Chinese Center for Disease Control and Prevention Beijing 102206 China

Objective Secreted proteins of Helicobacter pylori （H. pylori） interact with gastric epithelium cells and may contribute to cell damage. Considering the fact that HPO17S and hypothetical conserved protein HP1286 are included in the group and that HP0175 is a well-known apoptosis-induced factor, the present study aims to clarify whether HP1286 plays a role in bacterial pathogenicity or even functions as an apoptosis-induced factor in human stomach. Methods Two genes encoding HP1286 and HPO175 were cloned into pET32a vector and expressed as recombinant proteins in Escherichia coil （E. coil） BL21. Signal peptide sequences were not included. The recombinant proteins were purified with His SpinTrap and desalted by using HiTrap Desalting. Immunoreactivity of the proteins was determined by Western blot. Human gastric epithelial cell AGS was challenged with these endotoxin-free proteins; and apoptosis of cells was assayed with the Cell Death ELISA kit. Results Recombinant proteins and their respective products whose N-terminal his-tag were removed with thrombin were recognized by serum from the patient infected with H. pylori. Apoptotic AGS cells challenged by HP1286 of H. pylori 26695 were four times more than untreated cells. In addition, apoptosis-induced ability of HP1286 of SS1 was not as strong as that of H. pylori 26695 strain. Conclusion HP1286 of H. pylori 26695 induces apoptosis of AGS cells in a time-dependent manner, however the apoptosis-induced ability of HP1286 may differ due to variations between different strains.

关键词： H. pylori HP1286 AGS Apoptosis

Determination of 23 β_2-agonists and 5 β-blockers in animal muscle by high performance liquid chromatography-linear ion trap mass spectrometry

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Science china Chemistry 2010年第4期53卷 832-840页

作者： WU YongNing1,2, MIAO Hong1, FAN Sai1,2 & ZHAO YunFeng1,2 1 Institute of Nutrition and Food Safety, Chinese Centre for disease control and prevention, beijing 100021, china 2 College of Veterinary Medicine, china Agricultural University, beijing 100193, china 1. Institute of Nutrition and Food Safety Chinese Centre for Disease Control and Prevention Beijing 100021 China2. College of Veterinary Medicine China Agricultural University Beijing 100193 China

A high performance liquid chromatography-linear ion trap mass spectrometry method using isotope dilution technique has been developed for the simultaneous determination of 23 β2-agonists and 5 β-blockers in animal muscle tissues. Pork and chicken muscle samples were acid hydrolyzed and extracted with 5% trichloracetic acid in water, and then cleaned up using MCX solid phase extraction (SPE) cartridge. Methanol and 0.1% formic acid were used as mobile phases for gradient elution. A Waters AtlantisT3 column was used for separation. ESI positive ion scan mode was used with selective reaction monitoring. 9 β2-Agonists labeled by the deuterium isotope were used as internal standards for quantification. The linear ranges of 23 β2-agonists and 5 β-blockers were 5-200 μg/L, the coefficient of correlation was not less than 0.995, and the limit of detection for each compound in the muscle tissue was below 0.2 μg/kg. The recoveries of each compound in the spiked samples at three levels 5, 10, 20 μg/kg were in the range of 47.3%-123.7%, and the relative standard deviations were in the range of 3.2%-25.7%. The developed method is sensitive and specific for the determination of β2-agonists and β-blockers in pork and chicken muscle samples.

关键词： β2-agonists β-blockers muscle determination HPLC-ITMS

Analysis of causes for liver function deteriora-tion in patients with HIV/HCV co-infection

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Hepatobiliary & Pancreatic diseases International 2004年第4期3卷 538-542页

作者： Yong-Hong Zhang, Xin-Yue Chen, Yan Jiang, Yao Xiao, Zhen Liu, Xiao-Shan Long and Hao Wu beijing, china Department of Infectious diseases, beijing You’an Hospital and china center of disease of control and prevention , beijing 100054, china Department of Infectious diseases You'an Hospital Beijing 100054 China.

BACKGROUND:Co-infection of hepatitis C virus (HCV) and human immunodeficiency virus type 1 ( HIV-1 ) is common in hemophiliacs and drug abusers. To assess the interaction between HIV and HCV disease progression, we examined 82 HIV/HCV co-infection patients and 62 HCV infection patients. METHODS: Liver function, pathological changes, infec- tion duration, immune function and qualitative HCV-RNA and HCV antibody were compared retrospectively between the two groups of patients. RESULTS: Fourty-eight patients (58.5%) in the HIV/ HCV co-infection group and 53 patients (85.5%) in the HCV infection group showed abnormal liver function. No significant difference was observed in inflammation and fi- brosis in the two groups P =0.187, 0.954). However, liver abnormality in the patients with HIV/HCV co-infection appeared 8 years earlier than in those with HCV infection alone (P35 ± 173.49)×106/L and (914. 40 ±448. 28)×106/L, whereas in the HCV group they were (752.31±251.69)×l06/L and (529.011170.67)×106/L respectively. The difference in the two groups was highly significant (P3). CONCLUSION: HIV/HCV co-infection can accelerate de- terioration of hepatitis C, which may be due to the effect of HIV on cellular immunity and humoral immunity of the body.

关键词： HIV virus hepatitis C virus CD4+T cell HCV-RNA

Redevelopment of liftoff rates of saltating sand grains based on a simple optimization model

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Science china Earth Sciences 2010年第4期53卷 568-574页

作者： CHENG Hong & ZOU XueYong State Key Laboratory of Earth Surface Processes and Resource Ecology,beijing Normal University,beijing 100875,china MOE Engineering center of Desertification and Blown-sand control,beijing Normal University,beijing 100875,china Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of china,beijing Normal University,beijing 100875,china 1. State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China2. MOE Engineering Center of Desertification and Blown-sand Control Beijing Normal University Beijing 100875 China3. Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing 100875 China

This paper is a redevelopment result of liftoff rates of saltating sand grains based on our previous *** sand flow is a complex multi-phase flow because of a special two-phase gas-solid flow near ground *** extensive research on the movement of blowing sand,no model fully characterizes aeolian sand flow,and large differences often exist between simulations of aeolian sand movement and field *** key problem is a few of sufficient research on liftoff rates of saltating sand grains(also called the number of liftoff sand grains per unit time and per unit bed area).It is necessary to re-search in advance liftoff rates of saltating sand *** redeveloped liftoff rates of saltating sand grains by establishing an optimization model based on the flux of aeolian sand flow at different heights of the sampler in wind tunnel and the simulated capture of saltating sand grains by different heights of the sampler that are from different liftoff position(distance from the sampler) in order to revise previous inversion condition of liftoff rates of saltating sand *** rates increased rapidly with increasing wind *** frictional wind velocities of u=0.67,0.77,0.82,0.83,and 0.87 m s-1,liftoff rates were 3840,954502,5235114,5499407,and 7696291 sand grain s-1 m-2,*** rates could be expressed as the square of the instantaneous frictional wind velocity and a constant(0.663) that differs from the critical(threshold) frictional wind velocity at which saltation *** our results require additional experimental validation and the simple optimization model must be improved,they nonetheless provide a strong basis for future research.

关键词： liftoff rates of saltating sand grains optimization model wind tunnel two-phase gas-solid flow

Stability of SARS Coronavirus in Human Specimens and Environment and Its Sensitivity to Heating and UV Irradiation

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Biomedical and Environmental Sciences 2003年第3期16卷 246-255页

作者： SHU-MING DUAN, XIN-SHENG ZHAO, RUI-FU WEN, JING-JING HUANG, GUO-HUA PI, SU-XIANG ZHANG, JUN HAN, SHENG-LI BI, LI RUAN, XIAO-PING DONGAND SARS RESEARCH TEAMInstitute for Viral disease control and prevention, Chinese center for disease control and prevention,Ying-Xin Rd. 100, beijing 100052, china Institute for Viral disease control and prevention Chinese Center for Disease Control and Prevention Ying-Xin Rd. 100 Beijing 100052 China

Objective The causal agent for SARS is considered as a novel coronavirus that has never been described both in human and animals previously. The stability of SARS coronavirus in human specimens and in environments was studied. Methods Using a SARS coronavirus strain CoV-P9, which was isolated from pharyngeal swab of a probable SARS case in beijing, its stability in mimic human specimens and in mimic environment including surfaces of commonly used materials or in household conditions, as well as its resistances to temperature and UV irradiation were analyzed. A total of 106 TCID50 viruses were placed in each tested condition, and changes of the viral infectivity in samples after treatments were measured by evaluating cytopathic effect (CPE) in cell line Vero-E6 at 48 h after infectionn. Results The results showed that SARS coronavirus in the testing condition could survive in serum, 1:20 diluted sputum and feces for at least 96 h, whereas it could remain alive in urine for at least 72 h with a low level of infectivity. The survival abilities on the surfaces of eight different materials and in water were quite comparable, revealing reduction of infectivity after 72 to 96 h exposure. Viruses stayed stable at 4℃, at room temperature (20℃) and at 37℃ for at least 2 h without remarkable change in the infectious ability in cells, but were converted to be non-infectious after 90-, 60- and 30-min exposure at 56℃, at 67℃ and at 75℃, respectively. Irradiation of UV for 60 min on the virus in culture medium resulted in the destruction of viral infectivity at an undetectable level. Conclusion The survival ability of SARS coronavirus in human specimens and in environments seems to be relatively strong. Heating and UV irradiation can efficiently eliminate the viral infectivity.

关键词： Severe acute respiratory syndrome Coronavirus Stability Environment Specimen