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We elucidate the CO 2 mineralization mechanism with Mg-rich forsterite via theoretical approach including density functional theory (DFT) calculations and molecular dynamics (MD) simulations. Here, the CO 2 mineralization follows two steps: the ion dissolution pathway for dissolving Mg ions from the forsterite surface, and the cluster growth pathway, where ion pairs agglomerate into molecular-sized MgCO 3 clusters in aqueous solution. Step-by-step reaction mechanism for the dissolution of Mg ion was investigated via DFT calculations, and the formation procedure of solvated magnesite clusters and their structural changes over time were observed through MD simulations. Afterward, the effects of three control factors of pH, temperature, and hetero-metal ions were studied for both pathways. We found that the adjustment of pH contributed to the structural changes of the mineral surface and clustering ion pairs, which in turn affected the kinetics of reaction pathway. Also, high-temperature condition induced positive effects for accelerating both mineralization pathways. Lastly, calcium and ferrous ions showed opposite effects, promoting and hindering the overall processes, respectively. Importantly, our mechanistic study suggests that the pH of the solution changes alternatively between acid and base conditions during each mineralization pathway and pH condition induced by the preceding mineralization pathway facilitates the subsequent one. [ABSTRACT FROM AUTHOR]

Background: For treating displaced patella fractures, tension band wiring is the most widely used technique. However, implant removal surgery is often necessary to alleviate discomfort caused by fixation materials. On the contrary, fixation using nonabsorbable suture materials is anticipated to result in comparable outcomes without need for further implant removal surgery. However, there is a lack of clinical studies comparing the two fixation techniques (wire and nonabsorbable suture materials) for acute patella fractures. Methods: From 2014 to 2018, we retrospectively reviewed 60 patients who underwent open reduction with internal fixation for acute patella fracture. Thirty patients (group 1) who received surgery using tension band wiring and 30 patients (group 2) who received surgery using nonabsorbable suture materials were enrolled. The average follow-up period was more than 1 year after operation. Operation time, postoperative bone union time, range of motion (ROM) of the knee joint, postoperative clinical results, and complications were compared between the two groups. Result: Operation time, clinical bone union, and radiologic bone union were not statistically different between groups 1 and 2. At 3 months postoperatively, flexion was 120.3 ± 9.4° in group 1 and 110.5 ± 7.7° in group 2, showing statistically significant difference (p= 0.037). At 6 and 12 months postoperatively, the ROM was similar in both groups. Hospital for special surgery score at 3 months postoperatively was 78.4 ± 8.2 in group 1 and 83.7 ± 8.7 in group 2, showing statistically significant differences (p= 0.032). However, at 6 and 12 months postoperatively, there were no statistical differences. Lysholm score at 3 months postoperatively was 73.5 ± 8.1 in group 1 and 80.4 ± 8.2 in group 2, showing statistically significant difference (p= 0.016), but at 6 and 12 months postoperatively, there were no statistical differences. Conclusion: Fixation using multiple nonabsorbable suture materials can be an alternative surgical method in managing patella fractures, along with tension band wiring.

The cerebellum is a region of the brain that plays an important role in motor control. It is classified phylogenetically into archicerebellum, paleocerebellum and neocerebellum. The Purkinje cells are lined in a row called Purkinje cell layer and it has a unique dendritic branches with many spines.