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Background: Accurate implant placement in the optimal position is important to obtain favourable clinical outcomes and prevent complications in total joint arthroplasty. We aimed to assess the accuracy of implant placement based on three-dimensional (3D) preoperative planning for unlinked total elbow arthroplasty (TEA) and to clarify the effect of implant placement on clinical outcomes. Methods: This study included 20 patients (22 elbows, 17 with rheumatoid arthritis and 5 with osteoarthritis, with a mean follow-up period of 47 months) who underwent TEA with an unlinked-type implant after computed tomography (CT)-based 3D preoperative planning. Implant placement was planned preoperatively and several parameters were set to reflect it intraoperatively. TEA was performed based on the plan, and postoperative CT was conducted to evaluate differences in implant placement by comparing the preoperative plan and postoperative implant placement. Furthermore, we evaluated the relationship between implant placement differences and postoperative clinical outcomes, including range of motion, Visual Analogue Scale, Mayo Elbow Performance Score 1 year after surgery and complications at the last follow-up. Results: The mean absolute translation was within 2 mm, the mean absolute tilt was within 4°, the mean absolute rotation of the humeral component was within 4° and the mean absolute rotation of the ulnar component was 10.2° ± 6.8°. In the ulnar components, 15/22 (68%) cases were externally rotated, and the mean external rotation was 7.1° ± 10.2°. We defined the absolute ulnar component's rotational difference of more than 10° as a 'malrotation' group (n = 8) and 10° or less as a 'control' group (n = 14). We compared the clinical outcomes between both groups, however, no significant differences were observed in clinical outcomes and complications. Conclusions: We observed notable malrotation in the postoperative positioning of the ulnar component. Intraoperative support devices may be necessary to accurately reproduce the preoperative plan in the surgical field. Level of Evidence: Level IV (Therapeutic) [ABSTRACT FROM AUTHOR]

(CH3)4N[Ni(dmit)2]2 shows ordinary T-linear thermoelectric power of −40 µV/K at room temperature coming from the quasi-one-dimensional band, but β-(CH3)4N[Pd(dmit)2]2 shows small negative thermoelectric power of −20 to −10 µV/K at room temperature and T-inverse behavior at low temperatures. This is associated with the dimer Mott state, where the conduction band is derived from the half-filled highest occupied molecular orbital (HOMO). When the HOMO and the lowest unoccupied (LUMO) bands are taken as a whole, the lower HOMO bands afford negative thermoelectric power, whereas the upper two LUMO bands give positive thermoelectric power at the half filling; this relation is maintained even after the order of the HOMO and LUMO bands is inverted. The inclusion of the Coulomb repulsion U accounts for the observed small room-temperature thermoelectric power and the low-temperature T-inverse behavior. [ABSTRACT FROM AUTHOR]