This study analyzed data from the DEMETER satellite,collected 10 days before the Wenchuan M_(s)8.0 earthquake on May 12,2008.The time-frequency power spectrum of the data indicated a narrow-band radiative destabilizat...This study analyzed data from the DEMETER satellite,collected 10 days before the Wenchuan M_(s)8.0 earthquake on May 12,2008.The time-frequency power spectrum of the data indicated a narrow-band radiative destabilization(below the cut-off frequency)6 days prior to the earthquake.A significant anomaly in the Ez component was observed 3 days before the event.However,similar phenomena were found over aseismic regions,suggesting a link between ionospheric changes and the earthquake generation process.展开更多
[目的]研究Netrin1调控ELF3对子宫内膜癌HEC-1B细胞转移活性的影响。[方法]将36份组织样本分为2组:子宫内膜癌组、癌旁组,每组18份。蛋白免疫印迹检测癌组织和癌旁组织中Netrin1与ELF3的表达。将子宫内膜癌HEC-1B细胞设置为3组:siRNA N...[目的]研究Netrin1调控ELF3对子宫内膜癌HEC-1B细胞转移活性的影响。[方法]将36份组织样本分为2组:子宫内膜癌组、癌旁组,每组18份。蛋白免疫印迹检测癌组织和癌旁组织中Netrin1与ELF3的表达。将子宫内膜癌HEC-1B细胞设置为3组:siRNA NC组、siRNA Netrin1组和siRNA ELF3组。MTT实验法检测HEC-1B细胞的增殖能力,细胞划痕实验方法分析HEC-1B细胞的迁移能力,TUNEL实验检测HEC-1B细胞的凋亡率,蛋白免疫印迹方法分析HEC-1B细胞中Netrin1与ELF3蛋白的表达。[结果]与癌旁组织比较,子宫内膜癌组织Netrin1与ELF3的表达上调(0.19±0.06 vs 0.73±0.02,P<0.05;0.23±0.03 vs 0.69±0.08,P<0.05)。与siRNA NC组比较,siRNA Netrin1以及siRNA ELF3组的子宫内膜癌HEC-1B细胞增殖能力下降;siRNA Netrin1以及siRNA ELF3组的HEC-1B细胞迁移能力下降;siRNA Netrin1以及siRNA ELF3组的HEC-1B细胞凋亡率增加(1.15%±0.08%vs 10.31%±0.06%vs 9.96%±0.17%,P<0.05);siRNA Netrin1组的HEC-1B细胞Netrin1、ELF3表达降低(0.78±0.06 vs 0.31±0.07 vs 0.75±0.11,P<0.05;0.73±0.08 vs 0.25±0.03 vs 0.29±0.07,P<0.05);siRNA ELF3组的HEC-1B细胞ELF3表达降低。[结论]子宫内膜癌组织中Netrin1与ELF3的表达水平增加。抑制Netrin1表达后,子宫内膜癌HEC-1B细胞的增殖与迁移能力减弱,凋亡率增加,Netrin1对子宫内膜癌的作用与调控ELF3相关。展开更多
近年来,基于深度学习的恶意可执行与可链接格式(executable and linkable format,ELF)文件检测研究取得了显著进展。同时,关于模型对抗性攻击的研究也得到了广泛关注,攻击者可以通过生成对抗样本误导神经网络,使恶意软件被错误归类为良...近年来,基于深度学习的恶意可执行与可链接格式(executable and linkable format,ELF)文件检测研究取得了显著进展。同时,关于模型对抗性攻击的研究也得到了广泛关注,攻击者可以通过生成对抗样本误导神经网络,使恶意软件被错误归类为良性软件,从而逃逸检测。尽管已有多种生成对抗样本的方法被提出,但它们通常不适合对ELF文件进行修改,或缺乏在不同检测模型之间迁移的能力。为克服现有方法的局限性,提出了一种基于深度强化学习的恶意ELF文件检测对抗方法,该方法通过构造目标检测模型的最优扰动字节序列,能够在保留ELF文件原有功能的前提下生成对抗样本,而无须依赖目标模型的内部实现细节。实验结果表明,该方法生成的对抗样本针对目标检测模型的逃逸成功率达到76.80%,并能通过对抗训练提升目标检测模型的鲁棒性。展开更多
We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The ...We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud depends on the conductivity profile of the atmosphere. Quasi-static electric fields of a thundercloud decrease in those tropospheric regions where an increase of air conductivity is generated by pre-seismic activities due to emanation of radioactive gas and water into the lower atmosphere. The electric field becomes reduced in the lower troposphere, and the probability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticipate a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Spatial orientation of lightning strokes reduces vertical projection of their individual amplitudes, while the rate (median number strokes per a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the spectral content of ELF/VLF radio noise and changes the rate of detected pulses during the earthquake preparation phase.展开更多
基金National Natural Science Foundation of China(No.41274079,No.42304080)Seismic Safety and Health Monitoring of Major Construction Projects-Bridge and Reservoir Seismic Monitoring(No.DZ2024083000001)State Key Research and Development Plan under Grant(No.2018YFE0208300,No.2018YFC0603500).
文摘This study analyzed data from the DEMETER satellite,collected 10 days before the Wenchuan M_(s)8.0 earthquake on May 12,2008.The time-frequency power spectrum of the data indicated a narrow-band radiative destabilization(below the cut-off frequency)6 days prior to the earthquake.A significant anomaly in the Ez component was observed 3 days before the event.However,similar phenomena were found over aseismic regions,suggesting a link between ionospheric changes and the earthquake generation process.
文摘[目的]研究Netrin1调控ELF3对子宫内膜癌HEC-1B细胞转移活性的影响。[方法]将36份组织样本分为2组:子宫内膜癌组、癌旁组,每组18份。蛋白免疫印迹检测癌组织和癌旁组织中Netrin1与ELF3的表达。将子宫内膜癌HEC-1B细胞设置为3组:siRNA NC组、siRNA Netrin1组和siRNA ELF3组。MTT实验法检测HEC-1B细胞的增殖能力,细胞划痕实验方法分析HEC-1B细胞的迁移能力,TUNEL实验检测HEC-1B细胞的凋亡率,蛋白免疫印迹方法分析HEC-1B细胞中Netrin1与ELF3蛋白的表达。[结果]与癌旁组织比较,子宫内膜癌组织Netrin1与ELF3的表达上调(0.19±0.06 vs 0.73±0.02,P<0.05;0.23±0.03 vs 0.69±0.08,P<0.05)。与siRNA NC组比较,siRNA Netrin1以及siRNA ELF3组的子宫内膜癌HEC-1B细胞增殖能力下降;siRNA Netrin1以及siRNA ELF3组的HEC-1B细胞迁移能力下降;siRNA Netrin1以及siRNA ELF3组的HEC-1B细胞凋亡率增加(1.15%±0.08%vs 10.31%±0.06%vs 9.96%±0.17%,P<0.05);siRNA Netrin1组的HEC-1B细胞Netrin1、ELF3表达降低(0.78±0.06 vs 0.31±0.07 vs 0.75±0.11,P<0.05;0.73±0.08 vs 0.25±0.03 vs 0.29±0.07,P<0.05);siRNA ELF3组的HEC-1B细胞ELF3表达降低。[结论]子宫内膜癌组织中Netrin1与ELF3的表达水平增加。抑制Netrin1表达后,子宫内膜癌HEC-1B细胞的增殖与迁移能力减弱,凋亡率增加,Netrin1对子宫内膜癌的作用与调控ELF3相关。
文摘近年来,基于深度学习的恶意可执行与可链接格式(executable and linkable format,ELF)文件检测研究取得了显著进展。同时,关于模型对抗性攻击的研究也得到了广泛关注,攻击者可以通过生成对抗样本误导神经网络,使恶意软件被错误归类为良性软件,从而逃逸检测。尽管已有多种生成对抗样本的方法被提出,但它们通常不适合对ELF文件进行修改,或缺乏在不同检测模型之间迁移的能力。为克服现有方法的局限性,提出了一种基于深度强化学习的恶意ELF文件检测对抗方法,该方法通过构造目标检测模型的最优扰动字节序列,能够在保留ELF文件原有功能的前提下生成对抗样本,而无须依赖目标模型的内部实现细节。实验结果表明,该方法生成的对抗样本针对目标检测模型的逃逸成功率达到76.80%,并能通过对抗训练提升目标检测模型的鲁棒性。
文摘We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud depends on the conductivity profile of the atmosphere. Quasi-static electric fields of a thundercloud decrease in those tropospheric regions where an increase of air conductivity is generated by pre-seismic activities due to emanation of radioactive gas and water into the lower atmosphere. The electric field becomes reduced in the lower troposphere, and the probability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticipate a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Spatial orientation of lightning strokes reduces vertical projection of their individual amplitudes, while the rate (median number strokes per a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the spectral content of ELF/VLF radio noise and changes the rate of detected pulses during the earthquake preparation phase.
