We present periodicity search analyses on long-term radio light curves at 4.8,8,and 14.5 GHz of blazar PKS 0607–157 observed by the University of Michigan Radio Astronomical Observatory telescope.The highly variable ...We present periodicity search analyses on long-term radio light curves at 4.8,8,and 14.5 GHz of blazar PKS 0607–157 observed by the University of Michigan Radio Astronomical Observatory telescope.The highly variable radio emissions are approximately distributed as a log-normal probability distribution function.The Power Spectral Density for the radio light curves can be well characterized by a power-law model.Using the Weighted Wavelet Z-transform and Lomb-Scargle periodogram methods,significant Quasi-periodic Oscillation(QPO)of∼4.6 yr in the radio light curve has been observed above the 3σconfidence level,which presents an interesting case among blazar QPO phenomena.We explore three plausible physical models to explain the observed QPOs:a supermassive binary black hole system,Lense-Thirring precession of the disk,and helical motion of plasma blobs within the jet.展开更多
基于射频指纹(Radio Frequency Fingerprint,RFF)的物理层安全技术可以有效解决无线设备的安全接入问题,而特征提取作为射频指纹识别过程中的关键步骤,如何降低样本维度、减少测试训练时间、保证分类识别率是其研究的重要内容。针对上...基于射频指纹(Radio Frequency Fingerprint,RFF)的物理层安全技术可以有效解决无线设备的安全接入问题,而特征提取作为射频指纹识别过程中的关键步骤,如何降低样本维度、减少测试训练时间、保证分类识别率是其研究的重要内容。针对上述问题,提出了基于射频发射信号提取小波系数,通过Relief F算法和PCA算法,将信号维数降低到原来的29%,在能够保证SVM分类精度的情况下,有效减少了数据维度和时间消耗,同时降低了运算复杂度,适合运用在轻量级识别认证的终端环境。展开更多
目的探讨乳腺隆突性皮肤纤维肉瘤(dermatofibrosarcoma protuberans of the breast,DFSP-B)的临床病理学及分子学特征。方法回顾性分析21例DFSP-B的临床病理学、免疫表型及分子学特征,行HE、免疫组化及分子检测,并复习相关文献。结果21...目的探讨乳腺隆突性皮肤纤维肉瘤(dermatofibrosarcoma protuberans of the breast,DFSP-B)的临床病理学及分子学特征。方法回顾性分析21例DFSP-B的临床病理学、免疫表型及分子学特征,行HE、免疫组化及分子检测,并复习相关文献。结果21例DFSP-B患者男性6例,女性15例,年龄22~75岁(平均39.76岁,中位年龄36岁)。肿瘤最大径1~15 cm(平均4.7 cm,中位3 cm)。镜下瘤细胞呈席纹状、漩涡状及束状排列,核分裂象2~15个/10 HPF,侵犯脂肪及乳腺组织,符合DFSP-B;其中经典型DFSP-B 15例,经典型伴巨细胞纤维母细胞瘤(giant cell fibroblastoma,GCF)1例,黏液型2例,纤维肉瘤型隆突性皮肤纤维肉瘤(fibrosarcomatous-dermatofibrosarcoma protuberans,FS-DFSP)2例,FS-DFSP伴黏液型1例。免疫表型:CD34(21/21)、H3K27Me3(21/21)、β-catenin(21/21,胞膜)和WT-1(4/8,胞质)均阳性,Ki-67增殖指数为5%~50%。FISH检测DFSP-B中PDGFB基因分离阳性(7/8);3例FS-DFSP中PDGFB基因分离阳性(1/1),COL1A1-PDGFB融合阳性(1/1)。2例行NGS检测,其中1例FS-DFSP检测到CDKN2A基因(p.L16fs)突变及MSH6基因(p.F1088fs)突变;1例经典型伴GCF型检测到MLH1基因(p.R487)突变及TP53基因p.R273H体系突变。结论DFSP-B诊断需结合临床病理、免疫表型及PDGFB基因检测,治疗以手术切除为主,必要时可行放疗及靶向治疗,预后较好。展开更多
基金funded by the National Natural Science Foundation of China (NSFC) under No.11903028the support from the “Yunnan Revitalization Talent Support Program” of Yunnan province, China+2 种基金the University of Michigan Radio Astronomy Observatory, which is supported by the University of Michiganby a series of grants from the National Science Foundation, most recently AST-0607523NASA Fermi grants NNX09AU16G, NNX10AP16G, and NNX11AO13G.
文摘We present periodicity search analyses on long-term radio light curves at 4.8,8,and 14.5 GHz of blazar PKS 0607–157 observed by the University of Michigan Radio Astronomical Observatory telescope.The highly variable radio emissions are approximately distributed as a log-normal probability distribution function.The Power Spectral Density for the radio light curves can be well characterized by a power-law model.Using the Weighted Wavelet Z-transform and Lomb-Scargle periodogram methods,significant Quasi-periodic Oscillation(QPO)of∼4.6 yr in the radio light curve has been observed above the 3σconfidence level,which presents an interesting case among blazar QPO phenomena.We explore three plausible physical models to explain the observed QPOs:a supermassive binary black hole system,Lense-Thirring precession of the disk,and helical motion of plasma blobs within the jet.
文摘基于射频指纹(Radio Frequency Fingerprint,RFF)的物理层安全技术可以有效解决无线设备的安全接入问题,而特征提取作为射频指纹识别过程中的关键步骤,如何降低样本维度、减少测试训练时间、保证分类识别率是其研究的重要内容。针对上述问题,提出了基于射频发射信号提取小波系数,通过Relief F算法和PCA算法,将信号维数降低到原来的29%,在能够保证SVM分类精度的情况下,有效减少了数据维度和时间消耗,同时降低了运算复杂度,适合运用在轻量级识别认证的终端环境。
