%0 Thesis %A Yan, Rui %D 2019 %T The Development of Image Processing Algorithms in Cryo-EM %U https://hammer.purdue.edu/articles/thesis/The_Development_of_Image_Processing_Algorithms_in_Cryo-EM/8010332 %R 10.25394/PGS.8010332.v1 %2 https://hammer.purdue.edu/ndownloader/files/14923694 %K cryo electron microscopy %K cryo electron tomography %K image processing algorithms %K Beer-Lambert Law %K alignment accuracy %K thickness determination %K mean free path %K inelastic scattering %K least square methods %K Model-Based Iterative Reconstruction %K contrast improvement %K missing wedge artifacts reduction %K missing information restoration %K subtomogram averaging %K astigmatism correction %K objective lens stigmators %K single-pass tuning strategy %K defocus-dependent astigmatism %K magnification-dependent astigmatism %K Biophysics %K Structural Biology %K Computational Biology %X Cryo-electron microscopy (cryo-EM) has been established as the leading imaging technique for structural studies from small proteins to whole cells at a molecular level. The great advances in cryo-EM have led to the ability to provide unique insights into a wide variety of biological processes in a close to native, hydrated state at near-atomic resolutions. The developments of computational approaches have significantly contributed to the exciting achievements of cryo-EM. This dissertation emphasizes new approaches to address image processing problems in cryo-EM, including tilt series alignment evaluation, simultaneous determination of sample thickness, tilt, and electron mean free path based on Beer-Lambert law, Model-Based Iterative Reconstruction (MBIR) on tomographic data, minimization of objective lens astigmatism in instrument alignment and defocus and magnification dependent astigmatism of TEM images. The final goal of these methodological developments is to improve the 3D reconstruction of cryo-EM and visualize more detailed characterization. %I Purdue University Graduate School