[Technology Review]

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Their thinking was that it ought to be possible to capture the complete 3-D structure from the diffraction pattern incident on a sphere. Instead of taking many images, an iterative algorithm could then distil the 3-D structure.

These guys demonstrated the technique numerically to reconstruct the shape of a poliovirus and also demonstrated it practically by reconstructing the 3-D shape shown above.

Since then the work has come in for some criticism. Other scientists have suggested that the technique cannot be scaled to objects of interesting size and that, in any case, it only works for things that are so thin that they are essentially two dimensional anyway.

Today, Miao and pals respond. They say the mathematical analysis suggesting that the technique only works for 2-D objects makes some unrealistic assumptions. In particular, it assumes that the spherical shell in which the image is recorded is infinitesimally thin.

By contrast, Miao and co say the shell has a finite thickness determined by the depth of the voxels used to capture the image. It is this, they say, that provides the extra information required for 3-D structure determination.

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Read the full story here: http://www.technologyreview.com/blog/arxiv/27440/?nlid=nldly&nld=2011-12-27