<p><br></p><p dir="ltr"><b>Description</b>: X-ray volume (xray3) registered to FIB-SEM of P7 mouse heart (jrc_mus-heart-1)</p><p dir="ltr"><b>X-ray ID</b>: xray3</p><p dir="ltr"><b>Protocol</b>: After re-embedding in Durcupan, a 3D micro-CT scan of the entire block was performed using an XRadia Versa 510 X-ray microscope (Zeiss Microscopy). The tomogram facilitated precise selection of Regions of Interest (ROIs) and defined tissue boundaries. Multiple scans were conducted using different settings, with 4× and 20× objective lenses for overview and ROI selection, respectively. The sample block was then re-mounted on a 1 mm copper post for improved charge dissipation and trimmed to the ROI using an ultramicrotome. After each trimming step, X-ray tomograms were collected. Finally, a thin conductive layer was applied, consisting of a 10 nm gold layer followed by a 100 nm carbon layer.</p><p dir="ltr"><b>Contributions</b>: X-ray microCT scans and trimming were performed by Zhiyuan Lu (HHMI/Janelia/EMSR). The sample collection through block trimming was supervised by Zhiheng Yu (HHMI/Janelia/EMSR). Regions of interest were selected by Christopher Bleck (HHMI/Janelia/EMSR), Wei-Ping Li (HHMI/Janelia/EMSR), Zhiyuan Lu, and Aubrey Weigel (HHMI/Janelia/CellMap Project Team). Data curation was handled by Rebecca Vorimo (HHMI/Janelia/CellMap Project Team) and Yurii Zubov (HHMI/Janelia/CellMap Project Team). The rest of the CellMap Project Team contributed to the overall development and review of the project. Aubrey Weigel provided oversight for the general project development.</p><p dir="ltr"><b>X-ray voxel size (nm)</b>:</p><p dir="ltr"><b>X-ray data dimensions (µm)</b>:</p><p dir="ltr"><b>Dataset URL</b>: <a href="https://data.janelia.org/wyp7H" rel="noreferrer" target="_blank">s3://janelia-cosem-datasets/jrc_mus-heart-1/jrc_mus-heart-1.zarr/recon-1/xray/xray-3/</a></p><p dir="ltr"><b>Resulting, registered FIB-SEM volume</b>: <a href="https://doi.org/10.25378/janelia.24020919" rel="noreferrer noopener" target="_blank">https://doi.org/10.25378/janelia.24020919</a><br></p><p><br></p><p dir="ltr"><b>Visualization website</b>: <a href="https://openorganelle.janelia.org/datasets/jrc_mus-heart-1" rel="noreferrer" target="_blank">https://openorganelle.janelia.org/datasets/jrc_mus-heart-1</a></p>