AUTOMATED CTF DETERMINATION

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 从二维单粒子电子图像重建大分子的三维结构，需要确定和校正对比度传递函数（CTF）和包络函数。提出了一种基于约束非线性优化的计算算法，实现了对CTF和包络函数模型中的关键参数的同时自动估计。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The three-dimensional reconstruction of macromolecules from two-dimensional single-particle electron images requires determination and correction of the contrast transfer function (CTF) and envelope function. A computational algorithm based on constrained nonlinear optimization is developed to estimate the essential parameters in CTF and envelope function model simultaneously and automatically.