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Inverse Curvature Flows of Rotation Hypersurfaces

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1692-1708页

作者： Yu Han JIN xian feng wang Yong WEI School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

We consider the inverse curvature flows of smooth,closed and strictly convex rotation hypersurfaces in space forms M_(κ)^(n+1)with speed function given by F^(-α),whereα∈(0,1]forκ=0,-1,α=1 forκ=1 and F is a smooth,symmetric,strictly increasing and 1-homogeneous function of the principal curvatures of the evolving *** show that the curvature pinching ratio of the evolving hypersurface is controlled by its initial value,and prove the long time existence and convergence of the *** second derivatives conditions are required on F.

关键词： Inverse curvature flow rotation hypersurface

Resistin does not down-regulate the transcription of insulin receptor promoter

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 313-318页

作者： Xiao-zhi QIAO xian-feng wang Zhe-rong XU Yun-mei YANG Department of Very Important Person the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Institute of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To detect the effect of resistin on the transcription of insulin receptor promoter. Methods: Luciferase reporter gene was fused downstream of human insulin receptor promoter and the enzymatic activity of luciferase was determined in the presence or absence of resistin. The resistin expressed with plasmid was stained with antibody against Myc tag which was in frame fused with resistin coding sequence, and then imaged with confocal microscopy. Results: The treatment of pIRP-LUC transfected cells with recombinant resistin did not result in significant difference in the enzymatic activity of luciferase compared to the untreated cells. Cell staining showed that green fluorescence could be observed in the cytoplasm, but not in the nucleus. Conclusion: The results suggest that the endogenous resistin may functionally locate in the cytoplasm, but does not enter the nucleus and not down-regulate the transcription of insulin receptor promoter.

关键词： Resistin Insulin receptor promoter Luciferase reporter gene

Synthesis and bioactivity of novel 3-(1-hydroxyethylidene)-5-substituted-pyrrolidine-2,4-dione derivatives

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Chinese Chemical Letters 2012年第9期23卷 1023-1026页

作者： B ao feng Han Qing Ming Shi xian feng wang Jian Bo Liu Sheng Qiang Chun Long Yang Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects Ministry of AgricultureNanjing Agricultural UniversityChina Nanjing 210095 Jiangsu Key Laboratory of Pesticide Science Nanjing Agricultural UniversityChina Nanfing 210095 College of Life Science Nanjing Agricultural UniversityChina Nanjing 210095

Ten novel 5-substituted derivatives of 3-（1-hydroxyethylidene）pyrrolidine-2,4-dione were synthesized. The compounds were confirmed by IR, 1H NMR, MS and elemental analysis. The bioassay indicated that these compounds showed noticeable herbicidal activities, and compounds 6f and 6j exhibited excellent inhibitory activities against the stalk of Echinochloa crusgalli, with ECso values of 94.4 and 72.7 rag/L, respectively.

关键词： Tenuazonic acid Pyrrolidine-2,4-dione Synthesis Herbicidal activity

Mechanical Properties and Microstructure of In Situ TiB_2-7055 Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 66-70页

作者： CHEN dong LE Yong-kang BAI Liang MA Nai-heng LI xian-feng wang Hao-wei The State Key laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 200030 China

In order to fabricate a kind of high strength particulate reinforced aluminum-matrix composites, the high strength aluminum alloy 7055 was selected as a matrix. Composites reinforced with varying amounts of TiB2 particles were synthesized using the in situ method, and their mechanical properties and microstructure were analyzed. It is found that the in situ TiB2 particles sized from 50 to 400 um uniformly disperse in the matrix. With the weight fraction of TiB2 particles increasing, the elastic modulus as well as the yield strength and the ultimate tensile strength increase, while the ductility decrease. The improvement of strength could be attributed to good bonding between TiB2 and the matrix, and also the TiB2 particles act as a barrier to dislocation.

关键词： metal matrix composite in situ mechanical properties microstructure

Digital Filter for Electrocardiogram Preprocessing Based on Microprocessor

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Chinese Journal of Biomedical Engineering(English Edition) 2010年第1期19卷 30-34页

作者： WU xian-wen wang feng School of Biological Science and Medical Engineering Southeast University Nanjing 210096 China

This paper proposes a different method to eliminate base wander and power line interference in electrocardiogram, which introduces the integer coefficient filter theory and gives the detail for designing digital filter to remove these two normal noise signals. Signal from the MIT-BIH electrocardiogram database was used to test the performance of the filter. From the test results, the performance of the digital filer is reDT good. The filter coefficient is an integer number, therefore, the filtering algorithm can be successfully implemented on the microprocessor.

关键词： digital filter electrocardiogram microprocessor noise removing MIT-BIH database

Two new C_(19)-diterpenoid alkaloids from roots Aconitum hemsleyanium var. atropurpureum

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Chinese Chemical Letters 2007年第6期18卷 704-707页

作者： Pei Tang, Dong Lin Chen, Xi xian Jian, feng Peng wang Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, Chengdu 610041, China Department of Chemistry of Medicinal Natural Products West China College of Pharmacy Sichuan University Chengdu 610041 China

A new franchetine-type C19-diterpenoid alkaloid 3-hydroxyfranchetine 1 and a new aconitine-type C19-diterpenoid alkaloid atropurpursine 2 have been isolated from the roots of Aconitum hemsleyanium var. atropurpureum. ... 详细信息

关键词： Aconitum hemsleyanium var. atropurpureum Rranunculaceae C19-diterpenoid alkaloid 3-Hydroxyfranchetine Atropurpursine

Three new C_(19)-diterpenoid alkaloids from Delphinium laxicymosum var. pilostachyum

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Chinese Chemical Letters 2007年第6期18卷 700-703页

作者： Ping Tang, Dong Lin Chen , Qiao Hong Chen, Xi xian Jian, feng Peng wang Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, Chengdu 610041, China Department of Chemistry of Medicinal Natural Products West China College of Pharmacy Sichuan University Chengdu 610041 China

Three new lycoctonine-type C19-diterpenoid alkaloids, laxicymine 1, laxicymisine 2, and laxicyminine 3 have been isolated from the whole herb of Delphinium laxicymosum var. pilostachyum W.T. wang. Their structures wer... 详细信息

关键词： Delphinium laxicymosum var. pilostachyum Ranunculaceae C19-diterpenoid alkaloid Laxicymine Laxicymisine Laxicyminine

TATB胺化废水中副产物1-氨基-3,5-二乙氧基-2,4,6-三硝基苯的鉴定分析

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火炸药学报 2017年第2期40卷 37-40,46页

作者：于宪峰周群王伯周中国人民解放军63961部队西安近代化学研究所

采用红外光谱、液相色谱-质谱联用技术和高分辨率质谱对间苯三酚法制备TATB的胺化废水中的副产物1-氨基-3,5-二乙氧基-2,4,6-三硝基苯(AETB)进行了定性鉴定。利用高效液相色谱建立了AETB的含量分析方法,确定了最佳实验条件,并采用外标... 详细信息

采用红外光谱、液相色谱-质谱联用技术和高分辨率质谱对间苯三酚法制备TATB的胺化废水中的副产物1-氨基-3,5-二乙氧基-2,4,6-三硝基苯(AETB)进行了定性鉴定。利用高效液相色谱建立了AETB的含量分析方法,确定了最佳实验条件,并采用外标法对此方法进行了检验。结果表明,色谱条件为:C18柱(250mm×4.6mm,5μm),流动相为乙腈-水(体积比85∶15),检测波长为224nm,进样量为10μL。外标法中所得峰面积与AETB的质量浓度呈线性关系,线性相关系数为0.999 8。该方法操作简单,无需对样品进行前处理,实验所得结果准确合理,可作为制备TATB产生的胺化废水中1-氨基-3,5-二乙氧基-2,4,6-三硝基苯残留量测定的方法。

关键词： TATB AETB 高效液相色谱外标法耐热炸药

Comparison of acute pneumonia caused by SARS-CoV-2 and other respiratory viruses in children:a retrospective multi-center cohort study during COVID-19 outbreak

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Military Medical Research 2021年第4期8卷 468-480页

作者： Guang-Li Ren xian-feng wang Jun Xu Jun Li Qiong Meng Guo-Qiang Xie Bo Huang Wei-Chun Zhu Jing Lin Cheng-He Tang Sheng Ye Zhuo Li Jie Zhu Zhen Tang Ming-Xin Ma Cong Xie Ying-Wen Wu Chen-Xi Liu Fang Yang Yu-Zong Zhou Ying Zheng Shu-Ling Lan Jian-feng Chen feng Ye Yu He BenQing Wu Long Chen Si-Mao Fu Cheng-Zhong Zheng Yuan Shi Department of Pediatrics General Hospital of Southern Theater Command of PLA111 Liuhua RoadYuexiu DistrictGuangzhou 510010GuangdongChina. Department of Pediatrics the Third People’s Hospital of ShenzhenShenzhen 518100GuangdongChina. Pediatric Intensive Care Unit Wuhan Children’s HospitalTongji Medical CollegeHuazhong University of Science&TechnologyWuhan 430010China. Pediatric Intensive Care Unit Maternal and Child Health Hospital of HuangshiHuangshi 435000HubeiChina. Department of Pediatrics the Second People’s Hospital of Guangdong ProvinceGuangzhou 510317China. Department of Pediatrics the Third Affiliated Hospital of Zunyi Medical University(the First People’s Hospital of Zunyi)Guizhou 563000China. Department of Pediatrics the Eighth People’s Hospital of GuangzhouGuangzhou 510440China. Department of Pediatrics the First Affiliated Hospital of Xinxiang Medical UniversityXinxiang 453100HenanChina. Pediatric Intensive Care Unit the Children’s Hospital Zhejiang University School of MedicineHangzhou 310000China. Department of Emergency/Critical Medicine Children’s Hospital of Nanjing Medical UniversityNanjing 210008China. Department of Pediatrics the Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260China. Department of Medical information date room General Hospital of Southern Theater Command of PLAGuangzhou 510010China. Department of Pediatrics the First Affiliated Hospital of Jinan UniversityGuangzhou 510632China. Department of Pediatrics Maternal and Child Health Hospital of YangjiangYangjiang 529500GuangdongChina. Department of Pediatrics Shenzhen Hospital Affiliated to the University of Chinese Academy of SciencesShenzhen 518107GuangdongChina. Department of Pediatrics Nanfang Hospital of Southern Medical UniversityGuangzhou 510515China. Department of Pediatrics Zhujiang Hospital of Southern Medical UniversityGuangzhou 510280China. Department of Pediatrics Military Hospital of 74 Group of PLAGuangzhou 510318China. Department of Neonatology

Background:Until January 18,2021,coronavirus disease-2019(COVID-19)has infected more than 93 million individuals and has caused a certain degree of *** pneumonia caused by common viruses such as respiratory syncytial virus,rhinovirus,human metapneumovirus,human bocavirus,and parainfluenza viruses have been more common in ***,the incidence of COVID-19 in children was significantly lower than that in *** purpose of this study was to describe the clinical manifestations,treatment and outcomes of COVID-19 in children compared with those of other sources of viral pneumonia diagnosed during the COVID-19 ***:Children with COVID-19 and viral pneumonia admitted to 20 hospitals were enrolled in this retrospective multi-center cohort study.A total of 64 children with COVID-19 were defined as the COVID-19 cohort,of which 40 children who developed pneumonia were defined as the COVID-19 pneumonia *** 284 children with pneumonia caused by other viruses were defined as the viral pneumonia *** epidemiologic,clinical,and laboratory findings were compared by Kolmogorov-Smirnov test,t-test,Mann-Whitney U test and Contingency table *** usage,immunotherapy,blood transfusion,and need for oxygen support were collected as the treatment ***,intensive care needs and symptomatic duration were collected as the outcome ***:Compared with the viral pneumonia cohort,children in the COVID-19 cohort were mostly exposed to family members confirmed to have COVID-19(53/64 vs.23/284),were of older median age(6.3 years vs.3.2 years),and had a higher proportion of ground-glass opacity(GGO)on computed tomography(18/40 vs.0/38,P<0.001).Children in the COVID-19 pneumonia cohort had a lower proportion of severe cases(1/40 vs.38/284,P=0.048),and lower cases with high fever(3/40 vs.167/284,P<0.001),requiring intensive care(1/40 vs.32/284,P<0.047)and with shorter symptomatic duration(median 5d vs.8d,P<0.001).The propor

关键词： Children Severe acute respiratory syndrome Coronavirus disease-2019 Viral pneumonia