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Three Super Active Regions in the Descending Phase of Solar Cycle 23

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 491-494页

作者： Hong-Qi Zhang, Xing-Ming Bao, Yin Zhang, Ji-Hong Liu, Shu-Dong Bao, Yuan-Yong Deng, Wei Li, Jie Chen, jin-ping dun, Jiang-Tao Su, Juan Guo, Xiao-Fan Wang, Ke-Liang Hu, Gang-Hua Lin and Dong-Guang WangNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 National Astronomical Observatories CAS NAOC Beijing 100012 China

We analyze the magnetic configurations of three super active regions, NOAA 10484, 10486 and 10488, observed by the Huairou Multi-Channel Solar Telescope (MCST) from 2003 October 18 to November 4. Many energetic phenomena, such as flares (including a X-28 flare) and coronal mass ejections (CMEs), occurred during this period. We think that strong shear and fast emergence of magnetic flux are the main causes of these events. The question is also of great interest why these dramatic eruptions occurred so close together in the descending phase of the solar cycle.

关键词： Sun: activity - Sun: flares - Sun: magnetic fields

Solar X-ray and EUV imager on board the FY-3E satellite

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Light(Science & Applications) 2022年第12期11卷 2939-2951页

作者： Bo Chen Xiao-Xin Zhang Ling-ping He Ke-Fei Song Shi-Jie Liu Guang-Xing Ding jin-ping dun Jia-Wei Li Zhao-Hui Li Quan-Feng Guo Hai-Feng Wang Xiao-Dong Wang Yun-Qi Wang Hong-Ji Zhang Guang Zhang Zhen-Wei Han Shuang Dai Pei-Jie Zhang Liang Sun Yang Liu software engineer Peng Wang Kun Wu Chen Tao Shi-Lei Mao Gui Mei Liang Yang Li-Heng Chen Chun-Yang Han Bin Huang Yang Liu mechanical engineer Shuai Ren Peng Zhou Ze-XiWei Xiao-Xue Zhang Yue Zhang Xin Zheng Yang Wang Ya Chen jing-Jiang Xie Fei He Qiao Song Wei-Guo Zong Xiu-Qing Hu Peng Zhang jing-Song Wang Zhong-Dong Yang Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Applied Optics Chinese Academy of SciencesChangchunChina National Satellite Meteorological Center China Meteorological AdministrationBeijingChina Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijingChina Innovation Center for Fengyun Meteorological Satellite(FYSIC) BeijingChina Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijingChina

The solar X-ray and Extreme Ultraviolet Imager(X-EUVI),developed by the Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences(CIOMP),is the first space-based solar X-ray and Extreme ultraviolet(EUV)imager of China loaded on the Fengyun-3E(FY-3E)satellite supported by the China Meteorological Administration(CMA)for solar *** started work on July 11,2021,X-EUVI has obtained many solar *** instrument employs an innovative dual-band design to monitor a much larger temperature range on the Sun,which covers 0.6-8.0 nm in the X-ray region with six channels and 19.5 nm in the EUV region.X-EUVI has a field of view of 42′,an angular resolution of 2.5″per pixel in the EUV band and an angular resolution of 4.1″per pixel in the X-ray *** instrument also includes an X-ray and EUV irradiance sensor(X-EUVS)with the same bands as its imaging optics,which measures the solar irradiance and regularly calibrates the solar *** radiometric calibration of X-EUVS on the ground has been completed,with a calibration accuracy of 12%.X-EUVI is loaded on the FY-3E satellite and rotates relative to the Sun at a uniform ***-field calibration is conducted by utilizing successive rotation solar *** agreement between preliminarily processed X-EUVI images and SDO/AIA and Hinode/XRT images indicates that X-EUVI and the data processing algorithm operate properly and that the data from X-EUVI can be applied to the space weather forecast system of CMA and scientific investigations on solar activity.

关键词： image instrument Solar

Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study

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World Journal of Gastroenterology 2025年第2期31卷 85-101页

作者： Jun-Yi Zhan Jie Chen jin-Zhong Yu Fei-Peng Xu Fei-Fei Xing De-Xin Wang Ming-Yan Yang Feng Xing Jian Wang Yong-ping Mu Cell Biology Laboratory Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Institute of Liver Diseases Shanghai Academy of Chinese MedicineShanghai 201203China Clinical Key Laboratory of Traditional Chinese Medicine of Shanghai Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Key Laboratory of Liver and Kidney Disease of the Ministry of Education Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Gastroenterology and Hepatology Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Institute of Liver Disease Fudan UniversityShanghai 200032China Evidence-Based Medicine Center Fudan UniversityShanghai 200032China Department of Gastrointestinal Endoscopy Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Hepatology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China

BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and *** its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are *** To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal *** This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 *** least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic *** validation was performed with bootstrap *** assessed the discrimination,calibration and accuracy of the model,and performed patient risk *** Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)*** predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation ***,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both *** We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients.

关键词： Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis

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World Journal of Clinical Cases 2025年第6期13卷 24-29页

作者： Wen-jin Yuan Yi-Juan Zheng Bing-Rong Zhang Yi-Jie Lin You Li Yan-Yan Qiu Xue-ping Yu Department of Infection Disease Clinical Medical Research Center for Bacterial and Fungal Infectious Diseases of Fujian provinceFujian Medical University Affiliated First Quanzhou HospitalQuanzhou 362000Fujian ProvinceChina

BACKGROUND Hydroxyurea,an antimetabolite,is frequently prescribed for various hemato-logical disorders,and its common side effects include gastrointestinal problems,cutaneous or mucosal lesions and pyrexia/*** SUMMARY This study reports the case of a 67-year-old woman who developed recurrent abdominal pain after 10 years of continuous hydroxyurea therapy for primary *** revealed an ileocecal *** discontinuing hydroxyurea therapy for 6 months,follow-up colonoscopy showed a significant reduction in the *** We consider cecal ulcers as a rare complication of hydroxyurea therapy which typically resolves upon stopping the drug.

关键词： Hydroxyurea Ulcer Abdominal pain Thrombocythemia Colonoscopy Case report

Synthesis and Vasodilatory Activities of New Pyrazolo[3,4-d] pyrimidin-4-one Derivatives

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Chinese Chemical Letters 2002年第7期13卷 613-616页

作者： ping GONG Yan Fang ZHAO dun WANG Shenyang Pharmaceutical University Shenyang 110016

A series of pyrazolo[3,4-d]pyrimidin-4-one derivatives were synthesized and tested for vasodilatory activities. All of them were new compounds and their structures were confirmed by IR, 1H NMR, MS and elemental analy... 详细信息

关键词： Pyrazolo [3,4-d] pyrimidin-4-ones synthesis vasodilatory activity.

Thrombotic pulmonary embolism of inferior vena cava during caesarean section:A case report and review of the literature

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World Journal of Clinical Cases 2022年第13期10卷 4226-4235页

作者： Lan Jiang Wei-Xiang Liang Yi Yan Shou-ping Wang Li Dai dun-jin Chen Department of Medical Ultrasound The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150Guangdong ProvinceChina Department of Cardiology The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150Guangdong ProvinceChina Department of Anesthesiology The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510015Guangdong ProvinceChina Department of Obstetrics and Gynecology The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510015Guangdong ProvinceChina

BACKGROUND Thrombotic pulmonary embolism(TPE)is one of the most critical diseases in obstetrics but is rarely reported in caesarean section(CS)because TPE patients in CS have a high risk of death and are difficult to *** case report of TPE during CS was recorded by transthoracic echocardiography(TTE)and can provide a reference for the differential diagnosis of critical illnesses in *** SUMMARY A 37-year-old pregnant woman with rheumatic heart disease(RHD),gravida 5 and para 1(G5P1),presented for emergency CS at 33 wk and 3 d of gestation under general anesthesia because of acute heart failure,pulmonary hypertension and *** placental removal during CS,TTE revealed a nascent thrombus in the inferior vena cava(IVC)that elongated,detached and fragmented leading to acute thromboembolic events and acute *** report presents the whole process and details of TPE during CS and successful rescue without any sequelae in the *** case gives us new ideas for the diagnosis of death or cardiovascular accidents during CS in pregnant women with heart disease and the detailed presentation of the rapid development of TPE may also elucidate new ideas for *** case also highlighted the importance of prophylactic anticoagulation in the management of heart disease during *** Pregnancy with heart failure could trigger inferior vena cava(IVC)-origin TPE during *** and timely treatment can avoid serious consequences.

关键词： Caesarean section Pulmonary embolism Thrombosis Heart failure Echocardiography Case report

Differential Representations of SO(4) Dynamical Group

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Communications in Theoretical Physics 2008年第7期50卷 63-68页

作者： ZHAO dun WANG Shun-jin LUO Hong-Gang School of Mathematics and Statistics Lanzhou University Lanzhou 730000 China Department of Physics Sichuan University Chengdu 610064 China Center of Theoretical Physics and Interdisciplinary Studies Lanzhou University Lanzhou 730000 China Institute of Theoretical Physics Academia Sinica Beijing 100080 China

In this paper we present systematic differential representations for the dynamical group SO(4).Theserepresentations include the left and the right differential representations and the left and the right adjoint differentialrepresentations in both the group parameter space and its coset *** are the generalization of the differentialrepresentations of the SO(3) rotation group in the Euler *** representations may find their applications in thestudy of the physical systems with SO(4) dynamical symmetry.

关键词： dynamical group differential representation group action coset space

Primary User-Awareness-Based Energy-Efficient Duty-Cycle Scheme in Cognitive Radio Networks

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Computers, Materials & Continua 2022年第3期70卷 5991-6005页

作者： Zilong jin Chengbo Zhang Kan Yao dun Cao Seokhoon Kim Yuanfeng jin School of Computer Science Nanjing University of Information Science and TechnologyNanjing210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)Nanjing University of Information Science and Technology Nanjing210044China Jiangsu Institute of Economic and Information Technology Nanjing210003China School of Computer and Communications Engineering Changsha University of Science and TechnologyChangsha410114China Department of Computer Software Engineering Soonchunhyang UniversityAsan31538Rep.of Korea Department of Mathematics Yanbian UniversityYanji133002China

Cognitive radio devices can utilize the licensed channels in an opportunistic manner to solve the spectrum scarcity issue occurring in the unlicensed ***,these cognitive radio devices(secondary users)are greatly affected by the original users(primary users)of licensed *** users have to adjust operation parameters frequently to adapt to the dynamic network environment,which causes extra energy *** consumption can be reduced by predicting the future activity of primary ***,the traditional prediction-based algorithms require large historical data to achieve a satisfying precision accuracy which will consume a lot of time and memory ***,many of these schemes lack methods to deal with the very busy network *** this paper,one semi-supervised learning algorithm,i.e.,tri-training,has been employed to investigate the prediction of primary *** on the prediction results of tri-training,a duty-cycle mechanism and an intermediate node selection approach are proposed to improve the energy *** results show the effectiveness of the proposed algorithm.

关键词： Cognitive radio tri-training duty-cycle intermediate node energy efficiency

Behavior modeling on the PIM performance in connectors using FEA method and circuit simulation

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The Journal of China Universities of Posts and Telecommunications 2021年第1期28卷 87-93页

作者： dun Shubo jin Qiuyan Bi Lingyu Wang Ziren Xie Jun The 54th Research Institute of CETC Shijiazhuang 050050China School of Information Science and Teehnology Southwest Jiaotong UniversityChengdu 614202China School of Electronie Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Coaxial connectors are generally regarded as a kind of potential passive non-linear source when magnetic materials are applied in the coating or under-plating, which may result in serious passive intermodulation(PIM) interference and degrade the communication quality. In this paper, the effect of connector coating materials on the PIM is theoretically studied using finite element analysis(FEA) and circuit simulations. Considering the material composition both in central and outer conductor, an FEA model of connector is proposed to identify the current density in magnetic material region. An equivalent circuit model expressing the nonlinearity in coating material is developed, coupled with the non-linear transfer model. The PIM product power of the connector with related material configuration is predicted by harmonic balance simulation. Intentionally design connector samples are used in PIM tests and the measurement results are consistent with the theoretical predictions. The PIM performance in coaxial connectors is demonstrated from the perspectives of both modeling analysis and experimental investigations.

关键词： passive intermodulation(PIM) finite element analysis(FEA) circuit model coaxial connector