Du Ming, Di Zichao Wendy, Gürsoy Doǧa, Xian R Patrick, Kozorovitskiy Yevgenia, Jacobsen Chris
Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA.
Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL 60439, USA.
J Appl Crystallogr. 2021 Feb 19;54(Pt 2):386-401. doi: 10.1107/S1600576721000194. eCollection 2021 Apr 1.
Upscaling X-ray nanoimaging to macroscopic specimens has the potential for providing insights across multiple length scales, but its feasibility has long been an open question. By combining the imaging requirements and existing proof-of-principle examples in large-specimen preparation, data acquisition and reconstruction algorithms, the authors provide imaging time estimates for howX-ray nanoimaging can be scaled to macroscopic specimens. To arrive at this estimate, a phase contrast imaging model that includes plural scattering effects is used to calculate the required exposure and corresponding radiation dose. The coherent X-ray flux anticipated from upcoming diffraction-limited light sources is then considered. This imaging time estimation is in particular applied to the case of the connectomes of whole mouse brains. To image the connectome of the whole mouse brain, electron microscopy connectomics might require years, whereas optimized X-ray microscopy connectomics could reduce this to one week. Furthermore, this analysis points to challenges that need to be overcome (such as increased X-ray detector frame rate) and opportunities that advances in artificial-intelligence-based 'smart' scanning might provide. While the technical advances required are daunting, it is shown that X-ray microscopy is indeed potentially applicable to nanoimaging of millimetre- or even centimetre-size specimens.
将X射线纳米成像扩展到宏观标本有潜力在多个长度尺度上提供深入见解,但其可行性长期以来一直是个悬而未决的问题。通过结合大标本制备、数据采集和重建算法中的成像要求及现有的原理验证示例,作者给出了关于X射线纳米成像如何扩展到宏观标本的成像时间估计。为得出这一估计,使用了一个包含多重散射效应的相衬成像模型来计算所需曝光量及相应辐射剂量。随后考虑了即将出现的衍射极限光源预期的相干X射线通量。这种成像时间估计尤其适用于全小鼠脑连接组的情况。要对全小鼠脑连接组进行成像,电子显微镜连接组学可能需要数年时间,而优化后的X射线显微镜连接组学可将其缩短至一周。此外,该分析指出了需要克服的挑战(如提高X射线探测器帧率)以及基于人工智能的“智能”扫描进展可能带来的机遇。虽然所需的技术进步令人望而生畏,但研究表明X射线显微镜确实有可能应用于毫米甚至厘米尺寸标本的纳米成像。