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Analysis of subscription characteristics and user mobility in different types of MMORPGs

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 121-128页

作者： PENG Hui SUN Yan-li wu hong School of Economics and Management Beijing University of Posts and Telecommunications Beijing 100876 China

Massively multiplayer online role-playing game（MMORPG） is one of the fastest-growing segments of the online game *** subscription refers to game accounts logged in during a certain period of *** user mobility explains the dynamics of subscriber size *** article explores the subscription characteristics and user mobility in different types of *** is found that subscription characteristics in different types of MMORPGs are marked by *** one hand,the curve of competition-based game subscription is linear,and the stability period is short,therefore it is necessary for the game operators to introduce new versions *** the other hand,the gradient rate of subscription in the community-based game is slow at first and then fast,and the stability period is long,hence it will take the game operator a long cycle to launch a new *** difference of subscription curve is caused by the fact that user mobility in competition-based game is higher than in the community-based game,as attractiveness of community-based game can maintain a longer period due to network *** purpose of the study is to help the game operator to understand the development stage and features of the game and to make effective decisions to attract more players.

关键词： virtual reality online game subscription characteristics user mobility subscription curve life cycle MMORPG

Static stress analysis of coupling superconducting solenoid coil assembly for muon ionization cooling experiment

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Nuclear Science and Techniques 2010年第1期21卷 29-34页

作者： PAN Heng WANG li wu hong GUO Xinglong XU Fengyu Institute of Cryogenics and Superconductivity Technology Harbin Institute of Technology Harbin 150080 China

The stresses in the coupling superconducting solenoid coil assembly,which is applied in the Muon Ionization Cooling Experiment (MICE),are critical for the structure design and mechanical stability because of a large diameter and relative high magnetic *** paper presents an analytical stress solution for the MICE coupling coil *** stress due to winding tension is calculated by assuming the coil package as a set of combined *** thermal and electromechanical stresses are obtained by solving the partial differential equations of displacement based on the power series expansion *** analytical stress solution is proved to be feasible by calculating stresses in a tested superconducting solenoid with 2.58 m bore at room *** analytical result of the MICE coupling coil is in good agreement with that of the finite element which shows that the transverse shear stress induced by Lorentz force is principally dominant to magnet instability.

关键词：螺线管线圈耦合线圈应力分析超导线圈组装电离实验冷却

Changes in the esophagogastric junction outflow obstruction manometric feature based on the Chicago Classification updates

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World Journal of Gastroenterology 2022年第30期28卷 4163-4173页

作者： Yue-Yuan li Wen-Ting Lu Jian-Xiang liu li-hong wu Meng Chen hong-Mei Jiao Department of Geriatrics Peking University First HospitalBeijing 100034China Department of Gastroenterology and Hepatology Peking University First HospitalBeijing 100034China

BACKGROUND The critical diagnostic criteria for esophagogastric junction outflow obstruction(EGJOO)were published in the latest Chicago Classification version 4.0(CCv4.0).In addition to the previous criterion[elevated integrated relaxation pressure(IRP)in supine position],manometric diagnosis of EGJOO requires meeting the criteria of elevated median-IRP during upright wet swallows and elevated intrabolus ***,with the diagnostic criteria modification,the change in manometric features of EGJOO remained *** To evaluate the esophageal motility characteristics of patients with EGJOO and select valuable parameters for confirming the diagnosis of *** We performed a retrospective analysis of 370 patients who underwent highresolution manometry with 5 mL water swallows×10 in supine,×5 in upright position and the rapid drink challenge(RDC)with 200 mL water from November 2016 to November 2021 at Peking University First ***-one patients with elevated integrated supine IRP and evidence of peristalsis were enrolled,with 24 patients meeting the updated manometric EGJOO diagnosis(CCv4.0)as the EGJOO group and 27 patients not meeting the updated EGJOO criteria as the isolated supine IRP elevated group(either normal median IRP in upright position or less than 20%of supine swallows with elevated IBP).Forty-six patients with normal manometric features were collected as the normal high-resolution manometry(HRM)*** esophageal sphincter(UES),esophageal body,and lower esophageal sphincter(LES)parameters were compared between *** Compared with the normal HRM group,patients with EGJOO(CCv4.0)had significantly lower proximal esophageal contractile integral(PECI)and proximal esophageal length(PEL),with elevated IRP on RDC(Plities in the esophagogastric junction than isolated supine IRP elevate

关键词： Esophagogastric junction outflow obstruction High-resolution manometry Esophageal motility disorders Upper esophageal sphincter Proximal esophagus

Polymorphisms of some cytokines and chronic hepatitis B and C virus infection

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World Journal of Gastroenterology 2009年第44期15卷 5610-5619页

作者： Qiu-Ju Gao Dian-wu liu Shi-Yong Zhang Min Jia li-Min Wang li-hong wu Shu-Yun Wang li-Xin Tong Department of Epidemiology Public Health College Hebei Medical University Shijiazhuang 050017 Hebei Province China Department of Preventive Medicine Bethune Military Medical College of PLA Shijiazhuang 050081 Hebei Province China Institution of Epidemiology Center for Disease Prevention and Control of Shijiazhuang Shijiazhuang 050011 Hebei Province China Department of Biochemistry Detection the People's Hospital of Hebei Province Shijiazhuang 050071 Hebei Province China Center of liver Diseases the First Affiliated Hospital of Hebei Medical University. Shijiazhuang 050031 Hebei Province China

AIM： To study the relationship between the polymorphisms in some cytokines and the outcome of hepatitis B virus （HBV） and hepatitis C virus （HCV） infection. METHODS： Samples were obtained from 203 patients infected with HBV and/or HCV while donating plasma in 1987, and 74 controls were obtained from a rural area of North China. Antibodies to HBV or HCV antigens were detected by enzyme-linked imrnunoassay. The presence of viral particles in the serum was determined by nested reverse-transcriptase polymerase chain reaction （PCR）. Hepatocellular injury, as revealed by alanine aminotransferase （ALT） and aspartate aminotransferase level, was detected by a Beckman LX-20 analyzer. DNA was extracted from blood cells. Then, the single nucleotide polymorphisms of IL-2-330, IFN-γ＋874, IL-10-1082/-592 and IL-4-589 were investigated by restriction fragment length polymorphism-PCR or sequence specific primer-PCR.RESULTS： Persistent infection with HBV, HCV, and HBV/HCV coinfection was associated with IL-2-330 TT genotype and T allele, IFN-γ＋874 AA genotype, and IL-10-1082 AA genotype. The clinical outcome of HBV and/or HCV infection was associated with IL-2-330 TT genotype and T allele, IFN-γ＋874 AA genotype, and IL-10-1082 AA genotype. IL-2-330 GG genotype frequency showed a negative correlation with clinical progression, IL-10-1082 AA genotype frequency showed a positive correlation and IL-10-1082 AG genotype frequency showed a negative correlation with clinical progression. HCV RNA positive expression was associated with IL-10-1082 AA genotype and the A allele frequency. Abnormal serum ALT level was associated with IL-10-592 AC genotype frequency and IL-4-589 CC genotype, CT genotype, and the C allele. CONCLUSION： These results suggest that polymorphisms in some cytokine genes influence persistent HBV and HCV infection, clinical outcome, HCV replication, and liver damage.

关键词： Hepatitis B Hepatitis C Single nucleotide polymorphism Disease susceptibility Outcome studies Cytokines

Application of Tandem Cascade to Design of Fan Stator with Supersonic Inflow

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Chinese Journal of Aeronautics 2010年第1期23卷 9-14页

作者： li Qiushi,wu hong,Zhou Sheng School of Jet Propulsion,Beijing University of Aeronautics and Astronautics,Beijing 100191,China School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

This article proposes a tandem cascade constructed to tackle the thorny problem of designing the high-loaded stator with a supersonic inflow and a large turning angle. The front cascade adopts a supersonic profile to reduce the shock wave intensity turning the flow into subsonic,while the rear cascade adopts a subsonic profile with a large camber offering the flow a large turning angle. It is disclosed that the losses would be minimized if the leading edge of the rear cas- cade lies close to the pressure side of the front cascade at a distance of 20% pitch in pitch-wise direction without either axial spacing or overlapping in axial direction. The 2D numerical test results show that,with the inflow Mach number of 1.25 and the turning angle of 52° ,the total pressure loss coefficient of the tandem cascade reaches 0. 106 ,and the diffusion factor 0. 745. Finally,this article has designed and simulated a high-loaded fan stage with the proposed tandem stator,which has the pressure ratio of 3.15 and the efficiency of 86.32% at the rotor tip speed of 495.32 m/s.

关键词： fan/compressor tandem cascade stator supersonic inflow

“S”-shaped isopolyoxotungstate cluster decorated by calcium ions

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Chinese Chemical Letters 2013年第4期24卷 283-286页

作者： Shuang Yao hong-li wu Zhi-Qi Lei Jing-Hui Yan En-Bo Wang College of Chemistry and Environmental Engineering Changchun University of Science and Technology Key Laboratory of Polyoxometalate Science of Ministry of Education Department of ChemistryNortheast Normal University

One novel ＂S＂-shaped isopolyoxotungstate Ca2（H20）12（Ca4（H20）18[H2WllO3712}.20H20 （1） has been successfully synthesized by the conventional aqueous solution method. Single-crystal X-ray diffraction analysis revealed that compound 1 crystallized in triclinic system, space group P 1, with lattice constants a= 12.591（3）A, b= 12.738（3） A, c= 17.961（4） A, α =98.97（3）°, β= 99.85（3）°, y= 93.42（3）°. The ＂S＂- shaped cluster was built from two （W11） subunits, four Ca2＋ linking units and two （Ca（H20）6}2＋ decorating fragments. The electrochemical properties of I have been investigated in details.

关键词： lsopolyoxotungstate"S"-shapedCalciumElectrochemistry

Expression,purification and serological analysis of hepatocellular carcinoma associated antigen HCA587 in insect cells

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World Journal of Gastroenterology 2003年第4期9卷 678-682页

作者： Bing li hong-Yan wu Xiao-Ping Qian Yan li Wei-Feng Chen Immunology Department of Peking University Health Science Center,Beijing,100083,China Immunology Department of Peking University Health Science Center 38 Xueyuan Road Beijing 100083 China. wfchen@***

AIM: In order to assess hepatocellular carcinoma associated antigen HCA587 as a potential target for immunotherapy,the Bac-to-Bac expression system was used to express recombinant protein HCA587 in insect ***: The cDNA encoding HCA587 gene was cloned into donor vector pFasBacHtb and recombinant pFasBac Htb587 was transformed into competent cells *** Bacmid-587 was transfected into Sf9 insect cells using CELLFECTIN, Recombinant HCA587 protein was produced in Sf9 insect cells after infection with recombinant baculovirus, and was purified using Ni-NTA resin. Sera from HCC patients were also screened using recombinant protein ***: The molecular weight of the recombinant protein HCA587 expressed in insect cells was approximately *** blot results proved the recombinant protein HCA587had the similar antigenicity with its native *** analysis told that the rate of seroreactivity to HCA587 was not high in HCC ***: The recombinant protein HCA587 was successfully expressed and purified using Bac-to-Bac expression system. It paved the way for generation of specific antibody and investigation of immunohistochemical analysis and immune responses of HCC in the future.

关键词： HCA587抗原肝细胞癌血清学检查免疫疗法免疫组织化学

Do Different Cyclooxygenase Inhibitors Impair Rotator Cufl Healing in a Rabbit Model？

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Chinese Medical Journal 2015年第17期128卷 2354-2359页

作者： Yi Lu Yue li Feng-Long li Xu li hong-wu Zhuo Chun-Yan Jiang Department of Sports Medicine Service Beijing Jishuitan Hospital Beijing 100035 China

Background： The effect of selective and non-selective cyclooxygenase （COX） inhibitors on tendon healing was variable. The purpose of the study was to evaluate the influence of non-selective COX inhibitor, ibuprofen and flurbiprofen axetil and selective COX-2 inhibitor, celecoxib on the tendon healing process in a rabbit model. Methods： Ninety-six New Zealand rabbits were used as rotator cuff repair models. After surgery, they were divided randomly into four groups： Ibuprofen （10 mg·kg^-1·d^-1）, celecoxib （8 mg·kg^-1·d^-1）, flurbiprofen axetil （2 mg·kg^-1·d^-1）, and control group （blank group）. All drugs were provided for 7 days. Rabbits in each group were sacrificed at 3, 6, and 12 weeks after tendon repair. Tendon biomechanical load failure tests were performed. The percentage of type I collagen on the bone tendon insertion was calculated by Pieric acid Sirius red staining and image analysis. All data were compared among the four groups at the same time point. All data in each group were also compared across the different time points. Qualitative histological evaluation of the bone tendon insertion was also performed among groups. Results： The load to failure increased significantly with time in each group. There were significantly lower failure loads in the celecoxib group than in the control group at 3 weeks （0.533 vs. 0.700, P = 0.002）, 6 weeks （0.607 vs. 0.763, P = 0.01）, and 12 weeks （0.660 vs. 0.803, P = 0.002）, and significantly lower percentage of type I collagen at 3 weeks （11.5% vs. 27.6%, P 0.001）, 6 weeks （40.5% vs. 66.3%, P = 0.005）, and 12 weeks （59.5% vs. 86.3%, P = 0.001）. Flurbiprofen axetil showed significant differences at 3 weeks （failure load： 0.600 vs. 0.700, P = 0.024; percentage of type I collagen： 15.6% vs. 27.6%, P = 0.001）, but no significant differences at 6 and 12 weeks comparing with control group, whereas the ibuprofen groups did not show any significant difference at each time point. Conclusions： Nonsteroidal anti-inflammatory drugs

关键词： Biomechanical Cyclooxygenase lnhibitors Healing Histological Rotator Cuff

Influence of support stiffness on vibrations of a planet gear system considering ring with flexible support

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Journal of Central South University 2020年第8期27卷 2280-2290页

作者： liU Jing PANG Rui-kun li hong-wu XU Jin State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China College of Mechanical Engineering Chongqing UniversityChongqing 400044China China North Vehicle Research Institute Beijing 100081China

Planet gear systems(PGSs)are key components of transmission *** and material characteristics of gearbox and shaft can affect the support stiffness and vibrations of *** ring gear flexibility should affect the vibrations of PGSs ***,most previous work did not completely consider the effects of the ring gear flexibility on the vibrations of PGSs and flexible supports of ring and sun ***,this paper presents a flexible-rigid coupling multi-body dynamic(FMBD)model for a PGS with the flexible supports and ring gear flexibility.A finite element model of ring gear is established to formulate the ring gear *** influences of clearance and damping of planet bearings on the vibrations of PGS are *** effects of flexible supports and ring gear flexibility on the vibrations of PGS under different moment and speed conditions are *** statistical parameters and peak frequencies of PGS from the proposed FMBD and previous rigid multi-body dynamic(RMBD)models are *** results denote that the flexible support has a great effect on the vibrations of *** paper can provide some guidance for the support structure design and vibration control for PGSs.

关键词： planet gear flexible-rigid coupling flexible supports ring gear flexibility vibrations