Efficiency of 2D alignment methods
Efficiency of 2D alignment methods
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DOI：
10.1016/s0304-3991(01)00154-1
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发表时间：
2002-07-01
期刊：
影响因子：
2.2
通讯作者：
Penczek, PA
中科院分区：
文献类型：
--
作者：
Joyeux, L;Penczek, PA
在单粒子分析中，二维图像的对齐是一个基本步骤，目的是将用电子显微镜观察到的生物大分子的各种粒子视图对齐。这一步的计算效率是一个决定性的因素，在设计的比对策略的大组噪声数据和三维结构的细化方法的发展。此外，对准方法的精度取决于用于有效地执行针对三个取向参数的穷举搜索的数值解而变化。分析了所选对准方法的计算复杂度，给出了每种方法的算术运算次数的估计，并根据电子显微镜成像的线性理论模拟出的图像进行了对准精度的测试。它表明，如果粒子视图的近似重心是已知的，可以提高对齐方法的效率。所考虑的方法的精度在很大程度上受到影响，特别是对于高噪声水平，插值步骤的顺序。（C）. 2002 Elsevier Science B.V.保留所有权利。
In single particle analysis, the alignment of two-dimensional images is a fundamental step aimed at bringing into register various particle views of biological macromolecules observed with the electron microscope. The computational efficiency of this step is a deciding factor in design of alignment strategies for large sets of noisy data and in development of three-dimensional structure refinement methods. In addition, the accuracy of the alignment method varies depending on the numerical solutions adopted to efficiently perform exhaustive searches for three orientation parameters. The selected alignment methods are analyzed in terms of their computational complexity and the estimates of numbers of arithmetic operations for each method are given, The tests of alignment accuracy are performed using images simulated in accordance with the linear theory of image formation in the electron microscope. It is demonstrated that the efficiency of the alignment methods can be improved if approximate centers of gravity of particle views are known. The accuracy of the methods considered is largely affected, particularly for high noise levels, by the order in which interpolation steps are applied. (C). 2002 Elsevier Science B.V. All rights reserved.