Detection of Neodymium-Rich Phase for Development of Coercivity in Neodymium-Iron-Boron-Based Alloys with Submicron-Sized Grains Using Positron Lifetime Spectroscopy

In order to evaluate the relationship between positron lifetime and microstructure, which contributes to the development of coercivity in hydrogenation-disproportionation-desorption-recombination (HDDR)-processed Nd-Fe-B-based alloys, detailed studies of positron lifetime spectroscopy were performed on HDDR-processed Nd-Fe-B-based alloys during desorption-recombination (DR) treatment. After the onset of coercivity, the change in positron lifetime closely corresponded to the change in intrinsic coercivity (H cJ ) with the progress of DR treatment. This result can be explained in terms of the grain size of the recombined Nd 2 Fe 14 B phases and the diffusion length of positrons, which annihilate in the matrix before reaching the grain boundary. Furthermore, positron lifetime spectroscopy was able to detect small changes in the grain boundary region very sensitively compared with thermal desorption spectroscopy (TDS) and X-ray diffraction (XRD). These changes in the grain boundary region caused the onset of coercivity attributed to the formation of Nd-rich intergranular phases. These results indicate that formation of a small amount of the Nd-rich intergranular phase during the DR process, which could be detected by positron lifetime spectroscopy, contributes to the onset of coercivity, even if NdH x phases remain

Dynamic movement of the Golgi unit and its glycosylation enzyme zones

Harada A., Kunii M., Kurokawa K., et al. Dynamic movement of the Golgi unit and its glycosylation enzyme zones. Nature Communications 15, 4514 (2024); https://doi.org/10.1038/S41467-024-48901-1.Knowledge on the distribution and dynamics of glycosylation enzymes in the Golgi is essential for better understanding this modification. Here, using a combination of CRISPR/Cas9 knockin technology and super-resolution microscopy, we show that the Golgi complex is assembled by a number of small ‘Golgi units’ that have 1-3 μm in diameter. Each Golgi unit contains small domains of glycosylation enzymes which we call ‘zones’. The zones of N- and O-glycosylation enzymes are colocalised. However, they are less colocalised with the zones of a glycosaminoglycan synthesizing enzyme. Golgi units change shapes dynamically and the zones of glycosylation enzymes rapidly move near the rim of the unit. Photobleaching analysis indicates that a glycosaminoglycan synthesizing enzyme moves between units. Depletion of giantin dissociates units and prevents the movement of glycosaminoglycan synthesizing enzymes, which leads to insufficient glycosaminoglycan synthesis. Thus, we show the structure-function relationship of the Golgi and its implications in human pathogenesis

Impact of anti-doping education and doping control experience on anti-doping knowledge in Japanese university athletes: a cross-sectional study

Abstract Background This study was conducted to elucidate the anti-doping (AD) education, doping control experience, and AD knowledge according to the World Anti-doping Code (Code) of Japanese university athletes. Methods We collected data from 514 male athletes (Mage = 19.53 years, SD = 1.13) and 629 female athletes (Mage = 20.99 years, SD = 1.07). We asked them about their experience undergoing doping control and the AD education they had received. Then, we assessed their AD knowledge using the World Anti-Doping Agency’s Athlete Learning Program about Health and AD (ALPHA) test. Results The results showed that 2.54% of the participants had undergone doping control. Further, 30.10% received AD education at least once, and 20.82% received AD education more than once. When comparing the ALPHA scores of athletes with/without doping test experience, we observed no significant difference. However, the ALPHA scores of athletes with/without AD education were significantly different; specifically, athletes who received AD education more than once had significantly higher ALPHA scores than non-educated athletes. Conclusion These results revealed that doping control experience was not related to AD knowledge and that AD education was associated with AD knowledge, suggesting that athletes who receive AD education more than once have more accurate AD knowledge than less educated athletes on this topic. The importance of AD education in promoting understanding of AD according to the Code in sports is highlighted in this study