LitCovid-sentences  

PMC:7473770 / 48996-51160 JSONTXT 6 Projects

Annnotations TAB TSV DIC JSON TextAE

Id Subject Object Predicate Lexical cue
T407 0-10 Sentence denotes Resolution
T408 11-142 Sentence denotes Resolution estimates are challenging for tissue reconstructions due to the absence of sharp edges or features of well defined size.
T409 143-213 Sentence denotes Here, we follow the approach known as Fourier-shell correlation (FSC).
T410 214-377 Sentence denotes Accordingly, an upper bound for the resolution is be obtained in the following way: the CT scan is split into two, and from each half a 3D volume is reconstructed.
T411 378-557 Sentence denotes After registry, that is, mutual alignment of the volumes, the correlation between the two independent reconstructions in Fourier space is plotted as function of spatial frequency.
T412 558-713 Sentence denotes This correlation must not necessarily reflect the pure system resolution, but instead the range of spatial frequencies over which the results are reliable.
T413 714-838 Sentence denotes As such it is not only affected by the system resolution but also by the sample contrast and the noise of the specific scan.
T414 839-1011 Sentence denotes Further, it represents an average over all structures, not taking into account that features with stronger/weaker contrast can correspondingly show higher/lower resolution.
T415 1012-1103 Sentence denotes Here the Fourier operation for FSC was implemented with a Kaiser-Bessel window of 7 pixels.
T416 1104-1249 Sentence denotes For the parallel-beam data, a central volume of 650 × 650 × 650 voxels was correlated, for the cone-beam data a volume of 685 × 680 × 250 voxels.
T417 1250-1384 Sentence denotes These sub-volumes were selected to obtain the average values for the tissue while minimizing contributions from paraffin-filled holes.
T418 1385-1441 Sentence denotes The correlation curves are shown in Appendix 2—figure 1.
T419 1442-1565 Sentence denotes The intersection of the curve with the half-bit threshold yields the resolution estimate, indicated with dashed black line.
T420 1566-1710 Sentence denotes Correspondingly, a half-period resolution of 0.71⁢μ⁢m and 0.39⁢μ⁢m (or better) is obtained for the parallel and cone beam dataset, respectively.
T421 1711-1921 Sentence denotes However, since the splitted dataset resulted in only 721 angles for the reconstruction, i.e. the resolution estimate is severely affected by under-sampling artifacts, and hence can only serve as an upper bound.
T422 1922-1967 Sentence denotes Appendix 2—figure 1 illustrates the analysis.
T423 1968-1988 Sentence denotes Appendix 2—figure 1.
T424 1990-2054 Sentence denotes Quantification of the 3D-resolution for the example of sample V.
T425 2055-2164 Sentence denotes FSC analysis was carried out for two independent reconstructions, each from half the projections of the scan.