Synchrotron Refraction Enhanced Tomography of an Intact Common Marmoset (<i>Callithrix jacchus</i>)

The common marmoset (Callithrix jacchus), a small new world monkey species, has been widely used in various scientific fields. It is necessary to understand connections between specific genotypes, their structure, and function;however, an anatomical atlas of the entire body of the common marmoset has not yet been reported. In addition to conventional absorption, refraction enhanced computed tomography (CT) based on synchrotron radiation can increase the contrast of boundaries between small absorption differences. In this study, to examine the potential of creating an anatomical atlas of the whole body of the common marmoset non-invasively, we visualized an intact marmoset using synchrotron refraction enhanced CT. The cryogenic marmoset was scanned using the medical imaging beamline at the SPring-8 synchrotron radiation research facility in JAPAN. The trabecular structure, articular cartilage, cruciate ligament in the knee joint, and small airways (diameter: > 400 μm) was clearly identified with 50 μm voxel size and 37 keV x-ray energy. The structure of the heart and branching vessels in the kidneys and liver were also identified without contrast agents, and the anatomical structure of the brain was slightly visible. These results show that synchrotron refraction enhanced CT is useful for creating an anatomical atlas non-invasively, and further studies are planned that will combine refraction enhanced CT and other imaging techniques to analyse the morphology and create a complete atlas of the whole body of the common marmoset.

Direct Observation of Thermoelectric Magnetic Convection in Unidirectionally Solidified Al-Cu Alloys

This study performed the time-resolved and in-situ observation of unidirectional solidification of A1-Cu and Sn-Bi alloys under a static magnetic field up to 0.45 T.Irt the case of Sn-Bi alloy,the static magnetic field reduced the local convection around the primary dendrite arms.No thermoelectric convection was detected.On the other hand,the thermoelectric convection was clearly observed in Al-Cu alloy.The observed convection was consistently explained by the thermoelectric magnetic convection.According to a simplified model,the thermoelectric magnetic convection can be induced if the difference in the thermoelectric power between the solid and the liquid phases is in the order of 1 μV/K and temperature gradient is several K/mm.