High Performance Computer Research Center, Institute Of Computing Technology, Chinese Academy of Sciences, Beijing, 100190, China.
University of Chinese Academy of Sciences, Beijing, China.
BMC Bioinformatics. 2020 Nov 18;21(Suppl 6):202. doi: 10.1186/s12859-020-3529-3.
Electron tomography (ET) is an important technique for the study of complex biological structures and their functions. Electron tomography reconstructs the interior of a three-dimensional object from its projections at different orientations. However, due to the instrument limitation, the angular tilt range of the projections is limited within +70 to -70. The missing angle range is known as the missing wedge and will cause artifacts.
In this paper, we proposed a novel algorithm, compressed sensing improved iterative reconstruction-reprojection (CSIIRR), which follows the schedule of improved iterative reconstruction-reprojection but further considers the sparsity of the biological ultra-structural content in specimen. The proposed algorithm keeps both the merits of the improved iterative reconstruction-reprojection (IIRR) and compressed sensing, resulting in an estimation of the electron tomography with faster execution speed and better reconstruction result. A comprehensive experiment has been carried out, in which CSIIRR was challenged on both simulated and real-world datasets as well as compared with a number of classical methods. The experimental results prove the effectiveness and efficiency of CSIIRR, and further show its advantages over the other methods.
The proposed algorithm has an obvious advance in the suppression of missing wedge effects and the restoration of missing information, which provides an option to the structural biologist for clear and accurate tomographic reconstruction.
电子断层扫描(ET)是研究复杂生物结构及其功能的重要技术。电子断层扫描通过对不同方向的投影进行重建,来重建三维物体的内部结构。然而,由于仪器的限制,投影的倾斜角度范围在+70 到-70 之间。缺失的角度范围称为缺失楔形物,会导致伪影。
在本文中,我们提出了一种新颖的算法,压缩感知改进迭代重建-重投影(CSIIRR),它遵循改进迭代重建-重投影的方案,但进一步考虑了样本中生物超微结构内容的稀疏性。所提出的算法保留了改进迭代重建-重投影(IIRR)和压缩感知的优点,从而实现了电子断层扫描的估计,具有更快的执行速度和更好的重建结果。我们进行了全面的实验,CSIIRR 在模拟和真实数据集上都进行了挑战,并与一些经典方法进行了比较。实验结果证明了 CSIIRR 的有效性和效率,并进一步显示了它优于其他方法的优势。
所提出的算法在抑制缺失楔形物效应和恢复缺失信息方面有明显的进步,为结构生物学家提供了一个清晰准确的断层重建选择。