Astatine-211(^(211)At,t_(1/2)=7.21 h)emitting twoαparticles with energies of 5.87 and 7.45 MeV,can lead to a high linear energy transfer(LET=98.84 ke V/μm)and short tissue range(50~90μm).Since the 1950s,^(211)At ha...Astatine-211(^(211)At,t_(1/2)=7.21 h)emitting twoαparticles with energies of 5.87 and 7.45 MeV,can lead to a high linear energy transfer(LET=98.84 ke V/μm)and short tissue range(50~90μm).Since the 1950s,^(211)At had stepped into endoradiotherapy and has always been regarded as one of the most promisingα-emitters for targeted-alpha therapy(TAT)in various malignancies.In the past two decades,^(211)At related radiopharmaceuticals have achieved great progress in the studies of basic physicochemical properties of astatine,^(211)At labeling strategies,preclinical and clinical studies,producing profound effects in nuclear medicine.This work will give a panorama of^(211)At-related researches in the recent 20 years,which will cover both the fundamental insights of^(211)At radiochemistry and applied labeling compounds.It can provide some important hints for the studies of TAT and other radiopharmaceuticals applied in tumor radiotherapy.展开更多
为完成极化合成孔径雷达(Pol SAR)图像中点散射像素目标的检测,从几何扰动滤波检测点散射像素的基本原理出发,分析了经典方法存在的相干度参数阈值无法自适应获取和不同散射机制共享同一阈值两个问题,提出利用Cloude-Pottier分解结果中...为完成极化合成孔径雷达(Pol SAR)图像中点散射像素目标的检测,从几何扰动滤波检测点散射像素的基本原理出发,分析了经典方法存在的相干度参数阈值无法自适应获取和不同散射机制共享同一阈值两个问题,提出利用Cloude-Pottier分解结果中熵参数的分布情况计算得到阈值,利用平均阿尔法角参数完成不同散射机制的初分类,对初分类的结果排序得到的某种散射机制对应的相干度参数的比例因子,根据比例因子计算得到该类散射机制的阈值,从而完成点散射目标的检测。对机载合成孔径雷达(AIRSAR)数据集中的San Francisco Bay图像进行了实验,结果表明,改进方法在检测性能上优于经典方法。展开更多
基金the financial supports from the National Natural Science Foundation of China(No.22006105)the China Postdoctoral Science Foundation(No.2020M683309)the Fundamental Research Funds for the Central Universities。
文摘Astatine-211(^(211)At,t_(1/2)=7.21 h)emitting twoαparticles with energies of 5.87 and 7.45 MeV,can lead to a high linear energy transfer(LET=98.84 ke V/μm)and short tissue range(50~90μm).Since the 1950s,^(211)At had stepped into endoradiotherapy and has always been regarded as one of the most promisingα-emitters for targeted-alpha therapy(TAT)in various malignancies.In the past two decades,^(211)At related radiopharmaceuticals have achieved great progress in the studies of basic physicochemical properties of astatine,^(211)At labeling strategies,preclinical and clinical studies,producing profound effects in nuclear medicine.This work will give a panorama of^(211)At-related researches in the recent 20 years,which will cover both the fundamental insights of^(211)At radiochemistry and applied labeling compounds.It can provide some important hints for the studies of TAT and other radiopharmaceuticals applied in tumor radiotherapy.
文摘为完成极化合成孔径雷达(Pol SAR)图像中点散射像素目标的检测,从几何扰动滤波检测点散射像素的基本原理出发,分析了经典方法存在的相干度参数阈值无法自适应获取和不同散射机制共享同一阈值两个问题,提出利用Cloude-Pottier分解结果中熵参数的分布情况计算得到阈值,利用平均阿尔法角参数完成不同散射机制的初分类,对初分类的结果排序得到的某种散射机制对应的相干度参数的比例因子,根据比例因子计算得到该类散射机制的阈值,从而完成点散射目标的检测。对机载合成孔径雷达(AIRSAR)数据集中的San Francisco Bay图像进行了实验,结果表明,改进方法在检测性能上优于经典方法。