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NUMERICAL STUDIES ON THE PROPULSION AND WAKE STRUCTURES OF FINITE-Span FLAPPING WINGS WITH DIFFERENT ASPECT RATIOS

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Journal of Hydrodynamics 2010年第2期22卷 147-154页

作者： shao xue-ming pan ding-yi DENG Jian YUZhao-sheng Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027 China

An immersed-boundary method is used to investigate the flapping wings with different aspect ratios ranging from 1 to *** numerical results on wake structures and the performance of the propulsion are *** the case of the two-dimensional flapping foil,the wing-tip vortices appear for the flow past a three-dimensional flapping wing,which makes the wake vortex structures much *** results show that the leading edge vortex merges into the trailing edge vortex,connects with the wing tip vortices and then sheds from the wing.A vortex ring forms in the wake,and exhibits different patterns for different foil aspect *** of hydrodynamic performances shows that both thrust coefficient and efficiency of the flapping wing increase with increasing aspect ratio.

关键词： bionic mechanics finite-span flapping wing aspect ratio immersed-boundary method

Motion and deformation of immiscible droplet in plane Poiseuille flow at low Reynolds number

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Journal of Hydrodynamics 2016年第4期28卷 702-708页

作者：潘定一林雨青张凌新邵雪明 State Key Laboratory of Fluid Power and Mechatronic Systems Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang University

Droplet migration in plane Poiseuille flow is numerically investigated with a dissipative particle dynamics *** single droplet deformation in the channel flow is first studied to verify the current method and the physical *** effect of the viscosity ratio between the droplet and the solvent and the effect of the confinement are systematically *** droplet is in an off-centerline equilibrium position with a specific selection of the parameters.A large viscosity ratio makes the droplet locate in a near-wall equilibrium position,and a large capillary number makes the droplet migrate to the near-centerline region of the *** the droplet migration at the same Capillary number,there is a critical width of the channel,which is less than twice of the droplet diameter,and the droplet will only migrate to the channel centerline if the width is less than this critical value.

关键词： droplet migration migrate viscosity Reynolds locate capillary systematically twice positions

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基于沉浸边界法的二维拍动翼数值模拟

空气动力学学报 2008年第4期26卷 419-424页

作者：潘定一邓见邵雪明浙江大学力学系流体传动及控制国家重点实验室浙江杭州310027

运用沉浸边界法对二维拍动翼流场进行了数值模拟,系统地分析了最大俯仰角、拍动频率和升沉俯仰运动的相位差等参数对拍动翼流场的影响。结果显示:当达到一定条件时,尾流出现反卡门涡街,使机翼得到正的推力而产生逆流前行的趋势。在本文... 详细信息

运用沉浸边界法对二维拍动翼流场进行了数值模拟,系统地分析了最大俯仰角、拍动频率和升沉俯仰运动的相位差等参数对拍动翼流场的影响。结果显示:当达到一定条件时,尾流出现反卡门涡街,使机翼得到正的推力而产生逆流前行的趋势。在本文的研究范围内发现,拍动翼的平均推力系数随最大俯仰角的增大先增大后减小,随着频率的增大而增大,同时,拍动翼的推进效率随最大俯仰角的增大而增大,随拍动频率的增大而减小,且当升沉俯仰运动的相位差在90°～100°之间时,存在着最大推进效率。本文所得结果为进一步研究鸟类飞行和鱼游等仿生力学提供了理论基础。

关键词：沉浸边界法仿生力学反卡门涡街拍动翼

亚声速无人机S弯进气道的多点多目标优化设计

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推进技术 2021年第3期42卷 495-504页

作者：曾丽芳胡建新潘定一黎军邵雪明浙江大学航空航天学院浙江杭州310027 浙江理工大学机械与自动控制学院浙江杭州310018

为提高亚声速无隔道式S弯进气道的整体气动性能,以提高总压恢复系数和降低畸变指数为设计目标,结合高精度数值模拟方法与第二代非劣排序遗传算法(NSGA-II),开展了无隔道式S弯进气道在马赫数0.25和0.7时的多目标优化设计。整个优化流程基... 详细信息

为提高亚声速无隔道式S弯进气道的整体气动性能,以提高总压恢复系数和降低畸变指数为设计目标,结合高精度数值模拟方法与第二代非劣排序遗传算法(NSGA-II),开展了无隔道式S弯进气道在马赫数0.25和0.7时的多目标优化设计。整个优化流程基于400个样本,最终得到四幅有效Pareto前沿图。从总压畸变Pareto前沿图中选取出优化算例并与原始进气道进行对比,结果表明:优化后的进气道中心线斜率入口段小、出口段大,而横截面面积分布的曲线斜率恰好相反;优化后的进气道低压区缩小、流动分离得到有效控制;虽然总压恢复系数提高有限,但是总压畸变得到大幅降低,在马赫数为0.25和0.7时,分别降低15.86%和23.61%。优化后的进气道在马赫数0.25~0.7整体性能得到有效改善。将该优化设计方法进一步推广应用于3个马赫数下的多点多目标优化设计,并得到了三维Pareto前沿图。

关键词： S弯进气道多点优化设计总压恢复总压畸变数值模拟

Enhancement of DNA vaccine-induced immune responses by a 72-bp element from SV40 enhancer

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Chinese Medical Journal 2007年第6期120卷 496-502页

作者： LI Hai-shan LIU Yong LI ding-feng ZHANG Ran-ran TANG Hai-li ZHANG Yu-wei HUANG Wei LIU ying PENG Hong XU Jian-qing HONG Kun-xue shao yi-ming State Key Laboratory for Infectious Disease Prevention and Control National Center for AIDS/STD Control and Prevention Chinese Center for Disease 100050 China

Background Although DNA vaccine is considered as the next generation of vaccine, most DNA vaccine candidates are still suffering from the relatively weak immunogenicity despite the increased dosage of plasmid DNA administered. In order to enhance the immune responses elicited by a codon-optimized HIV gag DNA vaccine, a modified plasmid vector pDRVI1.0 and a booster immunization with replicating Tiantan vaccinia （RTV） strain expressing the same gene were employed. Methods Vector pDRVI1.0 was constructed through inserting the 72-bp element from the SV40 enhancer, which was reported promoting nuclear transport of plasmid DNA, to the upstream of cytomegalovirus enhancer/promoter region of the plasmid vector pVR1012. Gene expression levels from expression plasmids based on pDRVI1.0 and pVR1012 were tested. Humoral and cellular immune responses induced by DNA vaccine alone or DNA prime-RTV boost regimen were determined in mice. Results It was shown that the 72-bp element significantly enhanced the gene expression level in non-dividing cells. gag-specific humoral and cellular immune responses induced by DNA vaccination were both significantly improved, while the Thl/Th2 balance was not obviously affected by the 72-bp element. RTV boosting further significantly enhanced DNA vaccine-palmed antibody and T cell responses in a Thl-biased manner. Conclusions The 72-bp SV40 enhancer element should be included in the DNA vaccine vector and RTV strain is a very efficient live vector for boosting immunization.

关键词： DNA vaccines SV40 enhancer prime-boost vaccinia Tiantan strain

Evaluation on the efficacy and safety of domestic bivalirudin during percutaneous coronary intervention

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Chinese Medical Journal 2013年第16期126卷 3064-3068页

作者： XIANG ding-cheng GU Xiao-long SONG Yao-ming HUANG Wei-jian TANG Liang-qiu yiN Yao-hui GENG shao-hua ZHOU Hao FAN Wen-mao HU Rong pan Chun-mei ZHANG yi XIAO Fang-yi WAN Huai-bin LIU Zeng-zhang Cardiovascular Department Guangzhou General Hospital ofGuangzhou Military Command Guangzhou Guangdong 510010China Cardiovascular Department Xinqiao Hospital Third MilitaryMedical University Chongqing 430037 China Cardiovascular Department First Affiliated Hospital of WenzhouMedical College Wenzhou Zhejiang 325000 China Cardiovascular Department Yuebei People's Hospital ShaoguanGuangdong 512026 China Cardiovascular Department Second Affiliated Hospital of Chongqing Medical University Chongqing 430331 China

Background Bivalirudin was widely used as an anticoagulant during coronary interventional procedure in western ***,it was not available in China before this clinical trial was *** randomized,single-blind and multicenter clinical trial aimed to evaluate the efficacy and the safety of domestic bivalirudin during percutaneous coronary intervention （PCI）.Methods A randomized,single-blind,multicenter trial was *** PCI candidates in five centers were randomized into a bivalirudin group and a heparin group,which were treated with domestic bivalirudin and non-fractional heparin during the PCI *** efficacy was evaluated by comparing the activated coagulation time （ACT）,the procedural success rate （residual stenosis ＜20％ in target lesions without any coronary artery related adverse events within 24 hours after PCI）,and the survival rate without major adverse cardiac events at 30 days after PCI between the two *** was evaluated by the major/minor bleeding *** A total of 218 elective PCI patients were randomized into a bivalirudin group （n=110） and heparin group （n=108）.Except for two patients needing additional dosing in the heparin group,the ACT values of all other patients in both groups were longer than 225 seconds at 5 minutes after the first intravenous *** success rates were respectively 100.0％ and 98.2％ in the bivalirudin group and heparin group （P＞0.05）.Survival rates without major adverse cardiac events at 30 days after PCI were 100.0％ in the bivalirudin group and 98.2％ in the heparin group （P＞0.05）.Mild bleeding rates were 0.9％ and 6.9％（P＜0.05） at 24 hours,and 1.9％ and 8.8％（P＜0.05） at 30 days after PCI in the bivalirudin group and heparin group *** was one severe gastrointestinal bleeding case in the heparin *** Domestic bivalirudin is an effective and safe anticoagulant during elective PCI *** efficacy is not inferior to heparin,but the safety is

关键词： bivalirudin heparin percutaneous coronary intervention anticoagulant

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鱼游推进的水动力学研究综述

舰船科学技术 2011年第B8期33卷 18-21页

作者：刘卉邵雪明潘定一赵良明中国舰船研究院北京100192 浙江大学力学系流体工程研究所浙江杭州310027

自然界中的鱼类游动时有着高速、高效和低噪等优点,人类一直以来试图通过对其游动机理的探索,获得借鉴并为自己所用。近一个世纪以来,在鱼游方面的研究已取得丰硕的成果。特别是近20年来,随着计算流体力学以及流动显示技术的发展,鱼游... 详细信息

自然界中的鱼类游动时有着高速、高效和低噪等优点,人类一直以来试图通过对其游动机理的探索,获得借鉴并为自己所用。近一个世纪以来,在鱼游方面的研究已取得丰硕的成果。特别是近20年来,随着计算流体力学以及流动显示技术的发展,鱼游推进重新成为研究热点。本文首先介绍了鱼类游动的分类,并在此基础之上分别对鱼形体波动、尾鳍拍动以及复杂流场下鱼游推进的相关研究工作进行了介绍和归纳。

关键词：鱼游推进水动力学形波运动拍动

Epidemiology,clinical and laboratory characteristics of currently alive HIV-1 infected former blood donors naive to antiretroviral therapy in Anhui Province,China

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Chinese Medical Journal 2006年第23期119卷 1941-1948页

作者： XU Jian-qing WANG Jian-jun HAN Li-feng XU Chen RUAN Yu-hua XU Zhen-hou CHEN Xi LIU Zhen-dong WANG Jun SU Bing ding Xin-ping GAO Bing GU Yong-bin CAO Xiao-yun XING Hui HONG Kun-xue PENG Hong ZHAO Quan-bi YUAN Lin FENG yi ZHANG Gui-yun MA Li-ying WU Lan shao yi-ming State Key Laboratory for Infectious Disease Prevention and Control National Center for MDS/STD Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100050 China Reference Laboratory National Center for MDS/STD Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100050 China Anhui Provincial Center for Disease Control and Prevention Hefei230000 China Fuyang Center for Disease Control and Prevention Fuyang 236000 China yingzhou Center for Disease Control and Prevention Fuyang 236000 China Funan Center for Disease Control and Prevention Fuyang 236000 China

Background Unregulated commercial blood/plasma collection among farmers occurred between 1992 and 1995 in central China and caused the second major epidemic of human immunodeficiency virus type 1 （HIV-1） infection in China. It is important to characterize HIV-l-infected former blood donors and to study characteristics associated with disease progression for future clinical intervention and vaccine development. Methods A cross-sectional study was performed on HIV-l-infected former blood donors （FBDs） and age-matched HIV-seronegative local residents. Demographic, epidemiologic, clinical and key laboratory data were collected from all study participants. Both unadjusted and adjusted multivariate linear regressions were employed to analyze the association of the decrease of CD4^＋ T-cell counts with other characteristics. Results Two hundred and ninety-four HIV-l-infected FBDs and 59 age-matched HIV-seronegative local residents were enrolled in this study. The unregulated blood/plasma collection occurred more than a decade （10.8 --12.8 years） ago, which caused the rapid spread of HIV-1 infection and the high prevalence of co-infection with hepatitis C virus （HCV, 89.5%）, hepatitis B virus （HBV） co-infection was observed in only 11 HIV＋participants （3.7%）. Deterioration in both clinical manifestation and laboratory parameters and increase of viral loads were observed in parallel with the decrease of CD4^＋ T-cell counts. The decrease of total lymphocyte counts （P〈0.001） and hemoglobin levels （P〈0.001） and the appearance of dermatosis （P=0.03） were observed in parallel with the decrease of CD4^＋ T-cell counts whereas viral loads （P〈0.001） and CD8^＋ T-cell counts （P=0.01） were inversely associated with CD4^＋ T-cell counts.Conclusions Co-infection with HCV but not HBV is highly prevalent among HIV-l-infected FBDs. CD4^＋ T-cell counts is a reliable indicator for disease progression among FBDs. Total lymphocyte counts, hemoglobin level and appearance of dermatosis were po

关键词： human immunodeficiency virus blood donors disease progression co-infection hepatitis C

Chemoprophylaxis, diagnosis, treatments, and discharge management of COVID-19: An evidence-based clinical practice guideline(updated version)

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Military Medical Research 2020年第3期7卷 249-282页

作者： ying-Hui Jin Qing-Yuan Zhan Zhi-Yong Peng xue-Qun Ren Xun-Tao yin Lin Cai Yu-Feng Yuan Ji-Rong Yue Xiao-Chun Zhang Qi-Wen Yang Jianguang Ji Jian Xia yi-Rong Li Fu-Xiang Zhou Ya-Dong Gao Zhui Yu Feng Xu ming-Li Tu Li-ming Tan Min Yang Fang Chen Xiao-Ju Zhang Mei Zeng Yu Zhu Xin-Can Liu Jian Yang Dong-Chi Zhao Yu-Feng ding Ning Hou Fu-Bing Wang Hao Chen Yong-Gang Zhang Wei Li Wen Chen Yue-Xian Shi Xiu-Zhi Yang xue-Jun Wang Yan-Jun Zhong ming-Juan Zhao Bing-Hui Li Lin-Lu Ma Hao Zi Na Wang Yun-Yun Wang shao-Fu Yu Lu-Yao Li Qiao Huang Hong Weng Xiang-ying Ren Li-Sha Luo Man-Ru Fan Di Huang Hong-Yang xue Lin-Xin Yu Jin-Ping Gao Tong Deng Xian-Tao Zeng Hong-Jun Li Zhen-Shun Cheng Xiao-Mei Yao Xing-Huan Wang Center for Evidence-Based and Translational Medicine Zhongnan Hospital of Wuhan UniversityWuhan 430071China National Clinical Research Center for Respiratory Diseases China-Japan Friendship HospitalBeijing 100029China Department of Pulmonary and Critical Care Medicine China-Japan Friendship HospitalBeijing 10029China Leishenshan Hospital in Wuhan Wuhan 430200China Department of Critical Care Medicine Zhongnan Hospital of Wuhan UniversityWuhan 430071China Institutes of Evidence-based Medicine and Knowledge Translation Henan UniversityKaifeng 475000HenanChina Department of Medical Imaging Guizhou Provincial People’s HospitalGuiyang 550002China Departments of Orthopedics Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Hepatobiliary Surgery Zhongnan Hospital of Wuhan UniversityWuhan 430071China National Clinical Research Center for Geriatrics West China Hospital of Sichuan UniversityChengdu 610041China Department of Geriatrics West China Hospital of Sichuan UniversityChengdu 610041China Department of Radiology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Clinical Laboratory Peking Union Medical College Hospital(PUMCH)Peking Union Medical CollegeChinese Academy of Medical Sciences(CAMS)Beijing 100730China Center for Primary Health Care Research Lund University and Region Skåne25002 MalmöSweden Emergency Center Zhongnan Hospital of Wuhan UniversityWuhan 403371China Department of Allergology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhan 43071China Department of Critical Care Medicine Renmin Hospital of Wuhan UniversityWuhan 430060China Department of Emergency Medicine and Chest Pain Center Qilu Hospital of Shandong UniversityJinan 250002China Department of Respiratory and Critical Care Medicine Suizhou Central HospitalHubei University of MedicineSuizhou 441300HubeiChina Department of Clinic Pharmacy Second People’s Hospital of Huaihua Ci

The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is the cause of a rapidly spreading illness,coronavirus disease 2019(COVID-19),affecting more than seventeen million people around the *** and treatment guidelines for clinicians caring for patients are *** the early stage,we have issued"A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus(2019-nCoV)infected pneumonia(standard version)";now there are many direct evidences emerged and may change some of previous recommendations and it is ripe for develop an evidence-based *** formed a working group of clinical experts and *** steering group members proposed 29 questions that are relevant to the management of COVID-19 covering the following areas:chemoprophylaxis,diagnosis,treatments,and discharge *** searched the literature for direct evidence on the management of COVID-19,and assessed its certainty generated recommendations using the Grading of Recommendations,Assessment,Development and Evaluation(GRADE)*** were either strong or weak,or in the form of ungraded consensus-based ***,we issued 34 *** them,6 were strong recommendations for,14 were weak recommendations for,3 were weak recommendations against and 11 were ungraded consensus-based *** covered topics of chemoprophylaxis(including agents and Traditional Chinese Medicine(TCM)agents),diagnosis(including clinical manifestations,reverse transcription-polymerase chain reaction(RT-PCR),respiratory tract specimens,IgM and IgG antibody tests,chest computed tomography,chest X-ray,and CT features of asymptomatic infections),treatments(including lopinavirritonavir,umifenovir,favipiravir,interferon,remdesivir,combination of antiviral drugs,hydroxychloroquine/chloroquine,interleukin-6 inhibitors,interleukin-1 inhibitors,glucocorticoid,qingfei paidu decoction,lianhua qingwen granules/capsules,convalescent plasma,lung

关键词： COVID-19 SARS-CoV-2 Recommendation Chemoprophylaxis Diagnosis Treatment Discharge management Traditional Chinese medicine guideline