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Primary cilia mediate Klf2-dependant Notch activation in regenerating heart

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Protein & Cell 2020年第6期11卷 433-445页

作者： xueyu li Qiang Lu Yuanyuan Peng Fang Geng Xuelian Shao Huili Zhou Ying Cao Ruilin Zhang School of life Sciences Fudan UniversityShanghai 200433China Shanghai Medical College Fudan UniversityShanghaiChina Department of Molecular and Cell Biology School of Life Sciences and TechnologyTongji UniversityShanghai 200331China School of Basic Medical Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Genetic Engineering Fudan UniversityShanghai 200433China

Unlike adult mammalian heart,zebrafish heart has a remarkable capacity to regenerate after *** study has shown Notch signaling activation in the endocardium is essential for regeneration of the myocardium and this activation is mediated by hemodynamic alteration after injury,however,the molecular mechanism has not been fully *** this study we demonstrated that blood flow change could be perceived and transmitted in a primary cilia dependent manner to control the hemodynamic responsive klf2 gene expression and subsequent activation of Notch signaling in the *** we showed that both homologues of human gene KLF2 in zebrafish,klf2a and klf2b,could respond to hemodynamic alteration and both were required for Notch signaling activation and heart *** experiments indicated that the upregulation of klf2 gene expression was mediated by endocardial primary ***,our findings reveal a novel aspect of mechanical shear stress signal in activating Notch pathway and regulating cardiac regeneration.

关键词： heart regeneration hemodynamics klf2 Notch signaling primary cilia

Technologies and studies of gas exchange in two-stroke aircraft piston engine:A review

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Chinese Journal of Aeronautics 2024年第1期37卷 24-50页

作者： Yu ZHOU xueyu li Shuiting DING Shuai ZHAO Kun ZHU Longtao SHAO Farong DU Gerui WANG Zheng XU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Civil Aviation University of China Tianjin 300300China Aero Engine Academy of China Beijing 101304China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310052China

The in-cylinder gas exchange process is crucial to the power performance of two-stroke aircraft piston engines,which is easily influenced by complex factors such as high-altitude performance variation and in-cylinder flow *** paper reviews the development history and characteristics of gas exchange types,as well as the current state of theory and the validation methods of gas exchange technology,while also discusses the trends of cutting-edge technologies in the *** paper provides a theoretical foundation for the optimization and engineering design of gas exchange systems and,more importantly,points out that the innovation of gas exchange types,the modification of theoretical models,and the technology of variable airflow organization are the key future research directions in this field.

关键词： Aircraft piston engine Aircraft power systems Gas exchange High-altitude performance In-cylinder flow Two-stroke Unmanned Aerial Vehicles(UAVs)

Quinoline-based anti-MRSA agents: Current development, structure-activity relationships, and mechanisms

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Chinese Chemical Letters 2024年第1期35卷 52-63页

作者： Hong Yao liping Cui Hang liu xueyu li lin Shen Ruige Yang Shangshang Qin Yong Guo College of Veterinary Medicine Henan Agricultural UniversityZhengzhou 450046China School of Pharmaceutical Sciences Zhengzhou UniversityZhengzhou 450001China Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study School of Pharmaceutical ScienceHengyang Medical SchoolUniversity of South ChinaHengyang 421001China

Methicillin-resistant Staphylococcus aureus (MRSA), the most common pathogen in hospital and community environments, can cause serious and even fatal infections. The antibiotics currently used for clinical treatment of MRSA have developed resistance, and there is an urgent need to develop new antimicrobials to treat infections caused by MRSA strains. Quinoline analogues play an important role in the development of antimicrobials. Herein, we discussed the current development of antibacterial activities of quinoline analogues, mainly for anti-MRSA activity, and their structure-activity relationships (SARs) from the perspective of using the quinoline nucleus to search for novel potential anti-MRSA candidates. Additionally, the mechanisms of some representative quinoline analogues against MRSA were clarified. Altogether, this review could provide further insights for the rational development of quinoline-based antibacterial drugs, especially against MRSA.

关键词： Quinoline analogue Methicillin-resistant Staphylococcus aureus Antibacterial activity Structure–activity relationship Antibacterial mechanism

A comprehensive aerodynamic-thermalmechanical design method for fast response turbocharger applied in aviation piston engines

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Propulsion and Power Research 2024年第2期13卷 145-165页

作者： Yu Zhou Yue Song Shuai Zhao xueyu li Longtao Shao Huansong Yan Zheng Xu Shuiting Ding Research Institute of Aero-Engine Beihang UniversityBeijing 100083China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing 100083China School of Energy and Power Engineering Beihang UniversityBeijing 100083China School of Transportation Science and Engineering Beihang UniversityBeijing 100083China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing 210000China Hangzhou International Innovation Institute Beihang UniversityHangzhou 311115China Civil Aviation University of China Tianjin 300300China

limited by the poor transient response performance of turbochargers,the dynamic performance of aviation piston engines tends to *** a bid to enhance the turbocharger’s acceleration capabilities,this study scrutinizes various factors impacting its *** on the operational principles and transient response process of the turbocharger,three types of in-ertiadnamely,aerodynamic inertia(ADI),thermal inertia(TI),and mechanical inertia(MI)d are identified and addressed for *** begin,this paper pioneers the innovative definition of a method for evaluating the transient response performance of the *** method incor-porates the introduction of an ADI parameter,inspired by the definition of ***,a thin-walled volute design with a low Biot number and a lightweight turbine impeller is introduced to reduce the turbocharger’s TI and *** simulation results of theflowfield distribution within the volute and diffuser demonstrate the comprehensive design method’s effectiveness in improving gas pressure and temperature distributions in these ***,the pressure distributionfluctuation in the constant moment-of-momentum volute(CMV)is 62.8%lower than that in the constant velocity moment volute(CVMV).The low-TI thin-walled volute not only en-hances the turbocharger’s response speed but also reduces its weight by approximately 40%.The impact of three types of inertia on the engine’s response speed is quantified as follows:ADI(94%)>MI(5%)>TI(1%).This conclusion has been verified through test results of both the turbocharger and the *** design method not only significantly improves the turbo-charger’s response performance but also offers valuable insights for the optimal design of other blade mechanical systems.

关键词： Turbocharger Fast response design method Aerodynamic inertia Thermal inertia Mechanical inertia

Circle Detection Based on HSI Color Space

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Computer Aided Drafting,Design and Manufacturing 2005年第1期15卷 36-40页

作者： MAOXia liXing-xin xueyu-li SchoolofElectronicandInformationEngineering BeijingUniversityofAeronauticsandAstronauticsBeijing100083China

A method based on HSI color space is presented to solve the problem of circle detection from color images. In terms of the evaluation to the edge detection method based on intensity, the edge detection based on hue is chosen to process the color image, and the simplified calculation of hue transform is discussed. Then the algorithm of circle detection based on Canny edge detection is proposed. Due to the dispersive distribution of the detected result, Hough transformation and template smooth are used in circle detection, and the proposed method gives a quite good result.

关键词： HSI color space edge detection circle detection Hough transformation

Gas exchange optimization in aircraft engines using sustainable aviation fuel:A design of experiment and genetic algorithm approach

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Energy and AI

Energy and AI 2024年第3期17卷 261-280页

作者： Zheng Xu Jinze Pei Shuiting Ding Longfei Chen Shuai Zhao Xiaowei Shen Kun Zhu Longtao Shao Zhiming Zhong Huansong Yan Farong Du xueyu li Pengfei Yang Shenghui Zhong Yu Zhou Hangzhou International Innovation Institute Beihang UniversityHangzhou311115China Research Institute of Aero-Engine Beihang UniversityBeijing102206China Civil Aviation University of China Tianjin300300China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing100083China Aero Engine Academy of China Beijing101304China School of Energy and Power Engineering Beihang UniversityBeijing100083China AVIC Chengdu Aircraft Design and Research Institute Chengdu610091China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing211106China School of Transportation Science and Engineering Beihang UniversityBeijing100083China Faculty of Science and Engineering University of Nottingham Ningbo ChinaNingbo315100China

The poppet valves two-stroke(PV2S)aircraft engine fueled with sustainable aviation fuel is a promising option for general aviation and unmanned aerial vehicle propulsion due to its high power-to-weight ratio,uniform torque output,and flexible valve ***,its high-altitude gas exchange performance remains unexplored,presenting new opportunities for optimization through artificial intelligence(AI)*** study uses validated 1D+3D models to evaluate the high-altitude gas exchange performance of PV2S aircraft *** valve timings of the PV2S engine exhibit considerable flexibility,thus the Latin hypercube design of experiments(DoE)methodology is employed to fit a response surface model.A genetic algorithm(GA)is applied to iteratively optimize valve timings for varying *** optimization process reveals that increasing the intake duration while decreasing the exhaust duration and valve overlap angles can significantly enhance high-altitude gas exchange *** optimal valve overlap angle emerged as 93°CA at sea level and 82°CA at 4000 m *** effects of operating parameters,including engine speed,load,and exhaust back pressure,on the gas exchange process at varying altitudes are further *** higher engine speed increases trapping efficiency but decreases the delivery ratio and charging efficiency at various *** effect is especially pronounced at elevated *** increase in exhaust back pressure will significantly reduce the delivery ratio and increase the trapping *** study demonstrates that integrating DoE with AI algorithms can enhance the high-altitude performance of aircraft engines,serving as a valuable reference for further optimization efforts.

关键词： Poppet valves two-stroke Design of experiment Genetic algorithm optimization Heavy fuel aircraft engine High altitude gas exchange performance

新常态下票据业务发展与中小企业融资——以上海为例

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金融理论与实践 2019年第4期 42-49页

作者：李雪玉中国人民银行上海总部上海200120

中国经济进入"新常态"以来,中国经济发展开始结构性减速。提高金融市场化程度,激发中小企业活力,稳步完成供给侧结构性改革是应对我国经济增速下行的最优选项。商业汇票作为服务实体经济的重要金融产品,期限短、流动性强,既可以满足中... 详细信息

中国经济进入"新常态"以来,中国经济发展开始结构性减速。提高金融市场化程度,激发中小企业活力,稳步完成供给侧结构性改革是应对我国经济增速下行的最优选项。商业汇票作为服务实体经济的重要金融产品,期限短、流动性强,既可以满足中小企业延期支付的诉求,也可以满足中小企业单笔融资金额小,融资频次高的短期融资需求。以上海市2014—2018年连续51个月商业汇票业务发展现状为例,系统分析商业汇票市场的总体发展情况、行业使用分布、票据流转现状以及票据违约情况。认为信息不对称、融资资格、融资成本与企业信用是影响商业汇票市场发展与中小企业融资的内在原因,未来可基于区块链技术优化票据管理、适时开展融资性票据业务并加速发展供应链票据融资业务从而推动票据市场发展。

关键词：金融市场票据市场商业汇票中小企业融资区块链技术

2型糖尿病患者内脏脂肪面积与糖尿病周围神经病变的相关性研究

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中华内分泌代谢杂志 2022年第3期38卷 195-200页

作者：郁静嘉李学毓李佳霖励丽宁波市第一医院内分泌科 315010

目的探讨2型糖尿病患者内脏脂肪面积(VFA)与糖尿病周围神经病变(DPN)的关系。方法2018年3月至2021年2月在宁波市第一医院纳入国家标准化代谢性疾病管理中心(MMC)的2615例2型糖尿病患者,对其进行病史采集、问卷调查、收集各项测定生化指... 详细信息

目的探讨2型糖尿病患者内脏脂肪面积(VFA)与糖尿病周围神经病变(DPN)的关系。方法2018年3月至2021年2月在宁波市第一医院纳入国家标准化代谢性疾病管理中心(MMC)的2615例2型糖尿病患者,对其进行病史采集、问卷调查、收集各项测定生化指标,并应用生物电阻抗法测定VFA、神经电生理检查筛查DPN。根据VFA和体重指数将患者分为以下4组:VFA<100 cm^(2)且体重指数<24 kg/m^(2)组[VA(-)OB(-)组]、VFA<100 cm^(2)且体重指数≥24 kg/m^(2)组[VA(-)OB(+)组]、VFA≥100 cm^(2)且体重指数<24 kg/m^(2)组[VA(+)OB(-)组]以及VFA≥100 cm^(2)且体重指数≥24 kg/m^(2)组[VA(+)OB(+)组]。进行多元logistic回归分析,以确定2型糖尿病患者VFA和体重指数与DPN的关系。结果本研究中DPN的比例为46.96%。DPN组年龄较大,男性比例较高,病程较长,吸烟比例较高,舒张压较低,HbA1C水平较高,总胆固醇较低,高密度脂蛋白胆固醇较低,低密度脂蛋白胆固醇较低,血肌酐水平较高,尿微量白蛋白/肌酐比值较高,VFA水平较高(均P<0.01)。根据VFA和体重指数的分组中,VA(+)OB(-)组有68.1%的患者合并DPN,为4组内最高。多因素logistic回归分析显示,与VA(-)OB(-)组相比,VA(+)OB(-)组发生DPN的风险显著增高(OR=2.234,95%CI 1.339~3.728,P=0.002),VA(+)OB(+)组次之(OR=1.281,95%CI 1.030~1.592,P=0.026)。结论无论体重指数是否超标,在2型糖尿病患者中VFA与DPN均密切相关。VA(+)OB(-)组DPN患病风险最高。内脏肥胖的评估对于早期筛查和防治2型糖尿病DPN具有重要临床意义。

关键词：糖尿病 2型糖尿病周围神经病变内脏脂肪面积国家标准化代谢性疾病管理中心

湘西北地区民乐式锰矿成矿地质特征及矿床成因

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地质科学 2014年第1期49卷 305-323页

作者：匡文龙李雪宇杨绍祥湖南科技大学土木工程学院湖南湘潭411201 湖南省地质矿产勘查开发局405队湖南吉首416007

在野外考察和室内综合研究基础上,从地层岩性、岩相古地理、地质构造等成矿地质条件的分析入手,结合稳定同位素测试数据分析,以古丈锰矿田中的野竹锰矿为例,对湘西北民乐式锰矿床的成矿地质特征及成矿机制进行了探讨,认为区内成矿物质(... 详细信息

在野外考察和室内综合研究基础上,从地层岩性、岩相古地理、地质构造等成矿地质条件的分析入手,结合稳定同位素测试数据分析,以古丈锰矿田中的野竹锰矿为例,对湘西北民乐式锰矿床的成矿地质特征及成矿机制进行了探讨,认为区内成矿物质(锰)是多来源的,但主要来源于海底火山活动。在成矿作用过程中,堆集在火山喷口附近的沉积物被烘热的海水淋滤改造,从中析出锰质;由热海水体所挟带,随海流迁移,成矿物质在裂陷槽中沉积下来富集形成锰矿床。民乐式锰矿床属离火山喷发中心较远的海底火山喷发一沉积锰矿床。

关键词：民乐式锰矿成矿地质特征矿床成因湘西北