回顾性分析了美国食品药品监督管理局制造商和用户设施设备体验(Manufacturer and User Facility Device Experience,MAUDE)数据库2021年1月至2024年6月的弹簧圈不良事件,结合山东省内医院调研和专家论证情况指出了弹簧圈在临床使用过...回顾性分析了美国食品药品监督管理局制造商和用户设施设备体验(Manufacturer and User Facility Device Experience,MAUDE)数据库2021年1月至2024年6月的弹簧圈不良事件,结合山东省内医院调研和专家论证情况指出了弹簧圈在临床使用过程中存在的风险点并进行了原因分析,提出了落实注册人的主体责任、提高使用单位的专业技能、强化监管部门的监管力度等改进措施,为弹簧圈的安全使用提供了参考。展开更多
It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be...It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be solved.A method of 3D structural color turning on periodic metasurfaces fabricated by the microlens array and self-assembly technology was proposed in this study.In the experiment,Polydimethylsiloxane(PDMS)flexible film was used as a substrate,and SiO2 microspheres were scraped into grooves of the PDMS film to form 3D photonic crystal structures.By adjusting the number of blade-coated times and microsphere concentrations,high-saturation structural color micropatterns were obtained.These films were then matched with microlens arrays to produce dynamic graphics with iridescent effects.The results showed that by blade-coated two times and SiO2 microsphere concentrations of 50%are the best conditions.This method demonstrates the potential for being widely applied in the anticounterfeiting printing and ultra-high-resolution display.展开更多
目的:本研究旨在分析2022年1月—2024年7月间美国FDA在新药申请(new drug application,NDA)过程中真实世界证据(real-world evidence,RWE)的使用情况及其对监管决策的影响,为基于RWE的药品审评决策和申请人新药研发提供参考。方法:通过...目的:本研究旨在分析2022年1月—2024年7月间美国FDA在新药申请(new drug application,NDA)过程中真实世界证据(real-world evidence,RWE)的使用情况及其对监管决策的影响,为基于RWE的药品审评决策和申请人新药研发提供参考。方法:通过查阅美国FDA官网的公共资源,提取2022年1月1日—2024年7月1日期间所有美国药物评价与研究中心(Center for Drug Evaluation and Research,CDER)批准的新分子实体(new molecular entity,NME)NDA申请的公开文件,分析RWE在NDA中的使用占比、类型、数据来源及支持作用。并总结美国FDA对RWE研究的反馈,包括研究设计、数据质量、偏倚与混杂因素控制等方面的问题。结果:研究发现,在纳入审查的77项NDA申请中,36项(47%)包含RWE研究;其中仅支持安全性的有19项(53%),仅支持有效性的有6项(17%),支持安全性和有效性的有11项(30%);作为主要证据提交的有9项(25%),作为支持性证据提交的有27项(75%);36项批准中17项(47%)是罕见病药品。美国FDA对RWE研究的反馈主要集中在研究设计问题、数据质量问题、偏倚与混杂因素控制不足等方面。结论:RWE在NDA中的应用日益广泛,但美国FDA在审评过程中提出了诸多局限性反馈。为了使RWE更好地支持审评决策,申请人应注重研究设计的科学性和严谨性、数据来源的可靠性和相关性以及研究过程的透明度,采用高质量的数据和科学的研究设计,以提高RWE在NDA中的适用性和可靠性。展开更多
针对频控阵多输入多输出(frequency diverse array multiple-input multiple-output,FDA-MIMO)雷达在目标定位过程中存在的角度和距离耦合问题,提出两种低复杂度角度-距离超分辨估计算法,即二维求根(two-dimensional rooting,2D-root)...针对频控阵多输入多输出(frequency diverse array multiple-input multiple-output,FDA-MIMO)雷达在目标定位过程中存在的角度和距离耦合问题,提出两种低复杂度角度-距离超分辨估计算法,即二维求根(two-dimensional rooting,2D-root)算法和重构旋转不变子空间(reduced dimensional estimation of signal parameters via rotational invariance techniques,RD-ESPRIT)算法。首先,提出角度-距离二维谱重构方法,将二维参数谱进行一维化等价剥离。区别于传统求根超分辨算法,2D-root算法利用矩阵化子空间求根方法,构造双重求根多项式,分别对角度和距离进行高精度估计及参数自动配对。同时,为了进一步减少求根运算的计算量,RD-ESPRIT算法利用重构后角度谱内在的线性关系,获得信号子空间的旋转不变性,从而实现目标角度的高效求解。计算机仿真实验结果表明,所提两种算法在降低传统搜索类目标定位算法复杂度的基础上,可提高参数估计精度。展开更多
The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled p...The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled phased array antenna system is a necessary trend for the future development of the phased array,and it is also a major focus and difficulty in the current research of integrated microwave photonics.This paper firstly introduces the basic principle and development history of optical true time delay phased array antenna system based on microwave photonics,and briefly introduces the main implementation methods and integration platform of optical true time delay.Then,the application and development prospect of optical true time delay technology in beam control of phased array antenna system are mainly presented.Finally,according to the current research progress,the possible research directions of integrated optically controlled phased array antenna systems in the future are proposed.展开更多
This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground commu...This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground communication.The array consists of ten broadside-radiating,ultrawide-beamwidth elements that are cascaded by a central-symmetry series-fed network with tapered currents following Dolph-Chebyshev distribution to provide low SLL.First,an innovative design of end-fire Huygens source antenna that is compatible with metal ground is presented.A low-profile,half-mode Microstrip Patch Antenna(MPA)is utilized to serve as the magnetic dipole and a monopole is utilized to serves as the electric dipole,constructing the compact,end-fire,grounded Huygens source antenna.Then,two opposite-oriented end-fire Huygens source antennas are seamlessly integrated into a single antenna element in the form of monopole-loaded MPA to accomplish the ultrawide,broadside-radiating beam.Particular consideration has been applied into the design of series-fed network as well as antenna element to compensate the adverse coupling effects between elements on the radiation performance.Experiment indicates an ultrawide Half-Power Beamwidth(HPBW)of 161°and a low SLL of-25 dB with a high gain of 12 d Bi under a single-layer configuration.The concurrent ultrawide beamwidth and low SLL make it particularly attractive for applications of UAV air-to-ground communication.展开更多
文摘回顾性分析了美国食品药品监督管理局制造商和用户设施设备体验(Manufacturer and User Facility Device Experience,MAUDE)数据库2021年1月至2024年6月的弹簧圈不良事件,结合山东省内医院调研和专家论证情况指出了弹簧圈在临床使用过程中存在的风险点并进行了原因分析,提出了落实注册人的主体责任、提高使用单位的专业技能、强化监管部门的监管力度等改进措施,为弹簧圈的安全使用提供了参考。
文摘It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be solved.A method of 3D structural color turning on periodic metasurfaces fabricated by the microlens array and self-assembly technology was proposed in this study.In the experiment,Polydimethylsiloxane(PDMS)flexible film was used as a substrate,and SiO2 microspheres were scraped into grooves of the PDMS film to form 3D photonic crystal structures.By adjusting the number of blade-coated times and microsphere concentrations,high-saturation structural color micropatterns were obtained.These films were then matched with microlens arrays to produce dynamic graphics with iridescent effects.The results showed that by blade-coated two times and SiO2 microsphere concentrations of 50%are the best conditions.This method demonstrates the potential for being widely applied in the anticounterfeiting printing and ultra-high-resolution display.
文摘目的:本研究旨在分析2022年1月—2024年7月间美国FDA在新药申请(new drug application,NDA)过程中真实世界证据(real-world evidence,RWE)的使用情况及其对监管决策的影响,为基于RWE的药品审评决策和申请人新药研发提供参考。方法:通过查阅美国FDA官网的公共资源,提取2022年1月1日—2024年7月1日期间所有美国药物评价与研究中心(Center for Drug Evaluation and Research,CDER)批准的新分子实体(new molecular entity,NME)NDA申请的公开文件,分析RWE在NDA中的使用占比、类型、数据来源及支持作用。并总结美国FDA对RWE研究的反馈,包括研究设计、数据质量、偏倚与混杂因素控制等方面的问题。结果:研究发现,在纳入审查的77项NDA申请中,36项(47%)包含RWE研究;其中仅支持安全性的有19项(53%),仅支持有效性的有6项(17%),支持安全性和有效性的有11项(30%);作为主要证据提交的有9项(25%),作为支持性证据提交的有27项(75%);36项批准中17项(47%)是罕见病药品。美国FDA对RWE研究的反馈主要集中在研究设计问题、数据质量问题、偏倚与混杂因素控制不足等方面。结论:RWE在NDA中的应用日益广泛,但美国FDA在审评过程中提出了诸多局限性反馈。为了使RWE更好地支持审评决策,申请人应注重研究设计的科学性和严谨性、数据来源的可靠性和相关性以及研究过程的透明度,采用高质量的数据和科学的研究设计,以提高RWE在NDA中的适用性和可靠性。
文摘针对频控阵多输入多输出(frequency diverse array multiple-input multiple-output,FDA-MIMO)雷达在目标定位过程中存在的角度和距离耦合问题,提出两种低复杂度角度-距离超分辨估计算法,即二维求根(two-dimensional rooting,2D-root)算法和重构旋转不变子空间(reduced dimensional estimation of signal parameters via rotational invariance techniques,RD-ESPRIT)算法。首先,提出角度-距离二维谱重构方法,将二维参数谱进行一维化等价剥离。区别于传统求根超分辨算法,2D-root算法利用矩阵化子空间求根方法,构造双重求根多项式,分别对角度和距离进行高精度估计及参数自动配对。同时,为了进一步减少求根运算的计算量,RD-ESPRIT算法利用重构后角度谱内在的线性关系,获得信号子空间的旋转不变性,从而实现目标角度的高效求解。计算机仿真实验结果表明,所提两种算法在降低传统搜索类目标定位算法复杂度的基础上,可提高参数估计精度。
基金supported by Fund of State Key Laboratory of IPOC(BUPT)(No.IPOC2021ZT16),China.
文摘The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled phased array antenna system is a necessary trend for the future development of the phased array,and it is also a major focus and difficulty in the current research of integrated microwave photonics.This paper firstly introduces the basic principle and development history of optical true time delay phased array antenna system based on microwave photonics,and briefly introduces the main implementation methods and integration platform of optical true time delay.Then,the application and development prospect of optical true time delay technology in beam control of phased array antenna system are mainly presented.Finally,according to the current research progress,the possible research directions of integrated optically controlled phased array antenna systems in the future are proposed.
基金supported by the National Natural Science Foundation of China(No.62371080 and 62031006)the National Science Foundation of Chongqing,China(No.CSTB2022NSCQ-MSX0597)the Venture&Innovation Support Program for Chongqing Overseas Returnees,China(No.cx2022063)。
文摘This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground communication.The array consists of ten broadside-radiating,ultrawide-beamwidth elements that are cascaded by a central-symmetry series-fed network with tapered currents following Dolph-Chebyshev distribution to provide low SLL.First,an innovative design of end-fire Huygens source antenna that is compatible with metal ground is presented.A low-profile,half-mode Microstrip Patch Antenna(MPA)is utilized to serve as the magnetic dipole and a monopole is utilized to serves as the electric dipole,constructing the compact,end-fire,grounded Huygens source antenna.Then,two opposite-oriented end-fire Huygens source antennas are seamlessly integrated into a single antenna element in the form of monopole-loaded MPA to accomplish the ultrawide,broadside-radiating beam.Particular consideration has been applied into the design of series-fed network as well as antenna element to compensate the adverse coupling effects between elements on the radiation performance.Experiment indicates an ultrawide Half-Power Beamwidth(HPBW)of 161°and a low SLL of-25 dB with a high gain of 12 d Bi under a single-layer configuration.The concurrent ultrawide beamwidth and low SLL make it particularly attractive for applications of UAV air-to-ground communication.
