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Background Studies on the material properties and dimensional accuracy of three-dimensionally (3D) printed denture base containing microcapsules with antifungal phytochemicals are lacking. Methods Two types of phytochemicals (phytoncide A and B) with antifungal activity were microencapsulated. The 3D-printed denture base specimens with minimum and maximum effective concentrations of microcapsules (6 and 8 wt% for phytoncide A; 15 and 25 wt% for phytoncide B) were prepared. The morphological changes of C. albicans on 3D-printed denture base with microcapsules was microscopically observed. The degree of conversion of 3D-printed denture base with microcapsules investigated. The microhardness and flexural strength values were also measured to evaluate the mechanical properties of 3D-printed denture bases. The dimensional accuracy (trueness) of the specimens with microcapsules was measured as root-mean-square values (RMS) for the whole, upper, and side surfaces of the specimens as well as their total height. For the degree of conversion, microhardness, and flexural strength values, the Kruskal–Wallis analysis and a post-hoc comparison using Mann–Whitney U test was performed. For the analysis of trueness (RMS), the one-way analysis of variance and a post-hoc comparison using Tukey’s method was conducted (α = 0.05). Results At both maximum and minimum effective concentrations of microcapsules, cell surface disruption or membrane breakdown of fungal cells were observed in the specimens. The groups with microcapsules (both phytoncide A- and B-filled) showed significantly lower microhardness and elastic modulus values than the control group (all, P = 0.001). For the trueness, all the RMS values of the whole, upper, and side surfaces of the specimens with microcapsules were less than 100 µm, although significantly higher than those without (all, P = 0.001). The mean flexural strength values of the groups with phytoncide A-filled microcapsule were higher than 65 MPa, not statistically different from that of the control group (all, P > 0.05). However, the groups with phytoncide B-filled microcapsules showed significantly lower values than the control (all, P = 0.001). Conclusions Within the limitations of this in-vitro study, the 3D-printed denture base containing 6 wt% of phytoncide A-filled microcapsules was clinically acceptable in terms of antifungal activity, dimensional accuracy, and flexural strength.

The position and velocity information of highspeed trains (HSTs) are essential to passenger safety, operational efficiency, and maintenance, for which an accurate navigation system is required. In this paper, we propose a twostage federated Kalman filter (TS-FKF) for an HST navigation system that uses multi-sensors, such as tachometer, inertial navigation system, differential GPS, and RFID, with a feedback scheme. However, the FKF with a feedback scheme often shows severe performance degradation in the presence of undetected large sensor errors. Tachometers often have large slip or slide errors during the train's acceleration, deceleration, and moving along a curved railway, and there are significant performance differences between different sensors. To make the proposed system robust to these errors, we propose a slip and slide detection algorithm for the tachometer and an adaptive information-sharing algorithm to deal with a large tachometer error and performance difference between sensors. We provide theoretical analysis and simulation results to demonstrate the performance of the proposed navigation system with the proposed algorithms.Index Terms-Train navigation system, positioning, slip and slide detection, sensor fusion, federated Kalman filter, information sharing.

Insertion of the LT #2 aligned with the teeth mark can result in a shallow insertion depth and inadequate ventilation. The measured distance from the cricoid cartilage to the upper incisor offers alternative guidance for correct LT insertion.