We will discuss algorithms needed to reconstruct physical images from optical and x-ray scattering measurements from non-crystalline materials. Such algorithms reconstruct the density map of the scattering object by applying physical constraints of positivity and smoothness to compensate for incomplete information. We will present applications to relate structure to function for RNA riboswitches and to obtain structural details at atomic resolution for gold nanoparticles. We will also discuss recent progress   in determining the structure of bacterial chromosomes.

Sebastian Doniach (born 1934) is a British-American physicist and professor at Stanford University. His research interests include theoretical condensed matter physics, superconductivity, and biophysics. Sebastian Doniach received a B.A. from Christ's College, Cambridge in 1954 and a Ph.D. from the University of Liverpool with Herbert Fröhlich in 1958. His contributions to the field of condensed matter physics include the Lawrence-Doniach model of superconductivity and his book on Green's functions in solid state physics with E. H. Sondheimer. Sebastian Doniach is one of the pioneers of synchrotron X-ray sources and served as the first director of the Stanford Synchrotron. His research group at Stanford currently uses radiation from the Stanford Synchrotron and from the Advanced Photon Source at Argonne National Laboratory for studies of protein and RNA structure and dynamics.