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Cu–Sb–Se ternary chalcogenide compounds composed of earth-abundant low-toxicity elements are attracting attention as economical and ecofriendly semiconductors. Among them, permingeatite (Cu3SbSe4) is a potential thermoelectric material with high Seebeck coefficient and low lattice thermal conductivity. However, it is necessary to improve its thermoelectric properties through doping, as it has low electrical conductivity due to its low intrinsic carrier concentration. In this study, samples of Cu3Sb1−x−ySnxInySe4 (0.02 ≤ x ≤ 0.08 and 0.04 ≤ y ≤ 0.06) double-doped with In (group 13 element) and Sn (group 14 element) at the Sb (group 15 element) sites of permingeatite were synthesized and their thermoelectric performances were evaluated. All samples exhibited a single phase of permingeatite with tetragonal structure, and high relative densities of 97.4–98.9%. The lattice constants of the a- and c-axes were 0.5651–0.5654 and 1.1249–1.1257 nm, respectively, owing to the successful substitution of Sn and In at the Sb sites. As the doping concentrations of Sn and In increased, the carrier (hole) concentration increased. Thus, the Seebeck coefficient decreased, while the electrical and thermal conductivities increased. Sn doping was found to be more effective than In doping. Because Cu3Sb0.96−xSnxIn0.04Se4 exhibits higher Seebeck coefficients than Cu3Sb0.94−xSnxIn0.06Se4, larger power factors and higher dimensionless figures of merit (ZTs) were achieved for the Cu3Sb0.96−xSnxIn0.04Se4 specimens. Cu3Sb0.92Sn0.04In0.04Se4 achieved a maximum ZT of 0.59 at 623 K, based on its Seebeck coefficient of 161 µVK−1, electrical conductivity of 4.69 × 104 Sm−1, thermal conductivity of 0.77 Wm−1K−1, and power factor of 1.22 mWm−1K−2.

Purpose: The accuracy and agreement of intraocular pressure (IOP) measurements using a noncontact self-measuring tonometer, TONO-i, compared with the Goldmann applanation tonometer (GAT).Methods: A total of 35 healthy participants and 42 primary open angle or normal tension glaucoma patients were enrolled in this study. TONO-i and GAT measurements were obtained and the mean difference in IOPs was analyzed using a paired t-test. IOP agreement was calculated using the two-way random effects model. Bland-Altman analysis and simple linear regression were used to estimate the disagreement between IOP measurements.Results: The mean IOPs measured using the TONO-i and GAT were 15.9 ± 3.3 mmHg and 16.4 ± 5.1 mmHg, respectively. In glaucoma patients, the mean values measured using the TONO-i (16.7 ± 4.1 mmHg) were lower than those measured using the GAT (17.9 ± 6.1 mmHg; p < 0.001). However, there was no significant difference among the healthy participants (p = 0.273). The intraclass coefficients (95% confidence interval) for all participants, normal participants, and glaucoma patients were 0.847 (0.702-0.920), 0.882 (0.804-0.941), and 0.828 (0.742-0.887), respectively, indicating good agreement between the IOP measurements. The mean difference and limits of agreement were not statistically significant. As IOP increased, the absolute difference between the GAT and TONO-i measurements also increased.Conclusions: The TONO-i, a novel tonometer, may be used reliably for IOP self-measurement and detecting IOP elevations. However, caution must be exercised because of the possibility of underestimating high IOPs.

Famatinite (Cu3SbS4 ) is a promising p-type thermoelectric material because of its low lattice thermal conductivity and high Seebeck coefficient. In this study, famatinite powders, double-doped with Sn (a BIV group element) and In (a BIII group element) to give Cu3Sb1-x-ySnxInyS4 (0.02 ≤ x ≤ 0.12 and 0.06 ≤ y ≤ 0.10), were synthesized by mechanical alloying and then consolidated by hot pressing. Phase analysis and microstructure observations were conducted over a range of doping levels, and the charge transport parameters and thermoelectric properties were evaluated. Except for the specimen with y = 0.10, in which the secondary phase CuInS2 was found, all the specimens exhibited a tetragonal famatinite phase without secondary phases. The Sn/In double doping increased the unit cell a-axis to 0.5387–0.5389 nm and changed the c-axis to 1.0744–1.0752 nm. As the temperature increased, the electrical conductivity decreased while the Seebeck coefficient increased, which indicates that the Sn/In double-doped famatinites have degenerate semiconductor characteristics. With increasing Sn and In content, the carrier concentration increased, so that the electrical conductivity increased and the Seebeck coefficient decreased. Cu3Sb0.80Sn0.12In0.08S4 exhibited the highest power factor, 0.87 mW m-1 K-2 at 623 K, with greatly increased thermal conductivity. Cu3Sb0.86Sn0.08In0.06S4 showed the highest value for the dimensionless figure of merit, ZT = 0.53 at 623 K, with a power factor of 0.78 mW m-1 K-2 and thermal conductivity of 0.90 W m-1 K-1.

Bytizite (Cu3SbSe3 ) has attracted interest as a promising thermoelectric material because of its ultralow thermal conductivity; however, there are few experimental studies. This study investigated the optimal processing conditions for the synthesis of Cu3SbSe3 using mechanical alloying (MA) and hot pressing (HP). The MA powder exhibited an orthorhombic Cu3SbSe3 phase, which remained even after HP. However, secondary phases of permingeatite (Cu3SbSe4) and berzelianite (Cu1.78Se) were also identified in the X-ray diffraction patterns. Thermal analysis revealed that the MA powder and HP compacts exhibited a large endothermic peak near 727 K, which corresponds to the melting point of Cu3SbSe3 . Dense compacts with a relative density higher than 99% were obtained at HP temperatures above 573 K. Microstructural and elemental analyses confirmed the presence of the secondary phase Cu3 SbSe4 in the matrix of Cu3SbSe3 . However, the Cu1.78Se phase could not be observed. All specimens exhibited an electrical conductivity of (0.66–1.06) × 10 3 Sm-1, a Seebeck coefficient of 324–376 µVK-1, and a power factor of 0.09–0.11 mWm-1K-2 at 623 K. The thermal conductivity was lower than 0.7 Wm-1K-1 in the measured temperature range, mainly due to the phonon scattering caused by the lone-pair electrons of Sb. A dip in thermal conductivity was observed at 423 K, which was possibly caused by the order-disorder transition of bytizite. The dimensionless figure of merit ZT increased with increasing temperature, and the maximum ZT was 0.16 at 623 K.

Objectives: Electrocardiography (ECG)-based diagnosis by experts cannot maintain uniform quality because individual differences may occur. Previous public databases can be used for clinical studies, but there is no common standard that would allow databases to be combined. For this reason, it is difficult to conduct research that derives results by combining databases. Recent commercial ECG machines offer diagnoses similar to those of a physician. Therefore, the purpose of this study was to construct a standardized ECG database using computerized diagnoses.Methods: The constructed database was standardized using Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT) and Observational Medical Outcomes Partnership–common data model (OMOP-CDM), and data were then categorized into 10 groups based on the Minnesota classification. In addition, to extract high-quality waveforms, poor-quality ECGs were removed, and database bias was minimized by extracting at least 2,000 cases for each group. To check database quality, the difference in baseline displacement according to whether poor ECGs were removed was analyzed, and the usefulness of the database was verified with seven classification models using waveforms.Results: The standardized KURIAS-ECG database consists of high-quality ECGs from 13,862 patients, with about 20,000 data points, making it possible to obtain more than 2,000 for each Minnesota classification. An artificial intelligence classification model using the data extracted through SNOMED-CT showed an average accuracy of 88.03%.Conclusions: The KURIAS-ECG database contains standardized ECG data extracted from various machines. The proposed protocol should promote cardiovascular disease research using big data and artificial intelligence.

Background: Fibrous dysplasia (FD) is a localized bone disorder in which fibro-osseous tissue replaces the normal bone structure. Patients with craniofacial FD often present with gradual swelling, deformity, and compromised vision or hearing. We previously introduced “the core extirpation method,” a novel surgical technique that is minimally invasive like traditional bone shaving but has longer-lasting effects. This study presents the long-term outcomes of our core extirpation method.Methods: We conducted a retrospective analysis of patients who underwent core extirpation for FD of the zygomaticomaxillary region from 2012 through 2021. Computed tomography (CT) scans were performed 6 to 12 months before the operation, immediately before and after the operation, and during follow-up visits. We performed all operations using the upper gingivobuccal approach, and we extirpated the core of the lesion while preserving the cortical structures of the zygoma and the maxilla to maintain symmetrical facial contour.Results: In 12 patients with lesions in the growth phase, anteroposterior/mediolateral (AP/ML) length discrepancies and the volume increased between preoperative and immediate postoperative CT scans. All patients’ immediate postoperative AP/ML discrepancies were stable up to 12–17 months postoperatively. Postoperative volume showed continuous lesion growth; the median volume growth rate was 0.61 cc per month.Conclusion: In this article, we present our experiences managing FD using the minimally invasive core extirpation technique, which entails small expected blood loss and can be performed as day surgery. It provides similar cosmetic outcomes as traditional bone shaving but with longer-lasting results. Although there are some limitations with the study’s retrospective nature and small sample size, our 4-year follow-up results show promising results of the core extirpation method in well-indicated patients.