A high-performance LiCoO 2 cathode was successively fabricated by a sol-gel coating of Al 2 O 3 to the LiCoO 2 particle surfaces and subsequent heat treatment at 600 °C for 3 h. Unlike bare LiCoO 2 , the Al 2 O 3 -coated LiCoO 2 cathode exhibits no decrease in its original specific capacity of 174 mA h/g (vs lithium metal) and excellent capacity retention (97% of its initial capacity) between 4.4 and 2.75 V after 50 cycles. A similar excellent capacity retention of the coated LiCoO 2 is also observed in a Li ion cell (C/LiCoO 2 ). This is because the high concentration of Al atoms at the particle surface region leads to the enhancement of structural stability of LiCoO 2 during cycling, which originates from the disappearance of the phase transition from a hexagonal to monoclinic phase.

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Background Electroencephalography (EEG)-based brain-computer interface (BCI) systems are mainly divided into three major paradigms: motor imagery (MI), event-related potential (ERP), and steady-state visually evoked potential (SSVEP). Here, we present a BCI dataset that includes the three major BCI paradigms with a large number of subjects over multiple sessions. In addition, information about the psychological and physiological conditions of BCI users was obtained using a questionnaire, and task-unrelated parameters such as resting state, artifacts, and electromyography of both arms were also recorded. We evaluated the decoding accuracies for the individual paradigms and determined performance variations across both subjects and sessions. Furthermore, we looked for more general, severe cases of BCI illiteracy than have been previously reported in the literature. Results Average decoding accuracies across all subjects and sessions were 71.1% (± 0.15), 96.7% (± 0.05), and 95.1% (± 0.09), and rates of BCI illiteracy were 53.7%, 11.1%, and 10.2% for MI, ERP, and SSVEP, respectively. Compared to the ERP and SSVEP paradigms, the MI paradigm exhibited large performance variations between both subjects and sessions. Furthermore, we found that 27.8% (15 out of 54) of users were universally BCI literate, i.e., they were able to proficiently perform all three paradigms. Interestingly, we found no universally illiterate BCI user, i.e., all participants were able to control at least one type of BCI system. Conclusions Our EEG dataset can be utilized for a wide range of BCI-related research questions. All methods for the data analysis in this study are supported with fully open-source scripts that can aid in every step of BCI technology. Furthermore, our results support previous but disjointed findings on the phenomenon of BCI illiteracy.

Structural instability of LiCoO2 can be improved by sol-gel coating of Al2O3 and subsequent heat-treatments. While Al2O3 phase does not exist after heat-treatments, solid solution LiCo1−xAlxO2 that has discretely higher Al concentration was formed at the surface up to ∼500 Å inside the particle. However, heat-treatment to 700°C results in the presence of the solid solution beyond ∼500 Å. The different Al concentration at the surface significantly affects the structural stability of the materials during cycling, and those prepared at 400°C do not show a phase transition from hexagonal to monoclinic phase. Disappearance of such a phase transition improves capacity retention of the cathode. Moreover, cathodes prepared at 400 and 500°C show improved layered characteristics with cation order. © 2001 The Electrochemical Society. All rights reserved.

ZrO 2 -coated LiCoO 2 showed negligible capacity loss up to 70 cycles at the cutoff voltage of 4.4 V, while bare LiCoO 2 exhibited ϳ60% of its original capacity after only 30 cycles. The improved electrochemical behavior was caused by the suppression of cobalt dissolution by nanoscale metal-oxide coating. The amount of cobalt dissolution in the electrolyte from the charged LiCoO 2 held at 25 and 90°C, respectively, correlates well with the capacity retention, among coatings of various metal oxides. The trend of the open-circuit voltage reduction is again well correlated with both the cobalt dissolution and capacity retention.

High-performance thin-film LiCoO2 cathodes were successfully fabricated by aluminum-oxide coating. Both the galvanostatic charge−discharge experiments and the cyclic voltammograms (CVs) showed enhanced electrochemical properties in the Al2O3-coated LiCoO2 films compared to those in the uncoated ones. The improved cycling behaviors in the coated samples are caused by the suppression of cobalt dissolution from the LiCoO2 thin films, with the formation of an aluminum-oxide solid electrolyte residing between the LiCoO2 cathode and liquid electrolyte. Galvanostatic intermittent titration technique (GITT) results clearly showed that the Al2O3-coated samples had higher Li diffusivities than the uncoated ones after 80 cycles. The effect of Al2O3 thickness on the electrochemical properties up to 300 nm was also studied.

Purpose To report the rate of technical complications and prosthesis survival in a cohort of edentulous patients treated with implant‐supported fixed complete dental prostheses (IFCDPs) after a mean observation period of at least 1 year. Materials and Methods The single‐visit examination included clinical and radiographic assessment, occlusal analysis, photographs and questionnaire assessing patient satisfaction in a cohort of 52 patients rehabilitated with 71 IFCDPs (supported by 457 implants). The IFCDPs were assessed for technical complications, number of implants and cantilever extension, retention type and prosthetic material type. Comparison was made between ceramic IFCDPs (Group 1) and metal‐resin IFCDPs (Group 2). Kaplan‐Meier survival curve analysis was carried out for assessment of prosthesis survival and was done for both Groups 1 and 2 separately. The Cox proportional hazard model was used for survival analysis, adjusting for a number of potential confounders, to evaluate the association between prosthesis survival and several risk factors such as type of opposing occlusion, nightguard use, and presence of bruxism. Responses to patient satisfaction questions were compared with Fisher's exact test. Results Out of 71 edentulous arches (52 patients) restored with IFCDPs, 6 IFCDPs had failed, yielding a cumulative prosthesis survival rate of 91.6 % after a mean observation period of 5.2 years (range: 1‐12 years) after definitive prosthesis insertion. Three IFCDPs were lost due to implant failures after 5.8 to 11 years of functional loading. Additionally, 3 metal‐resin IFCDPs failed due to technical complications. Minor complications were the most frequent complications observed, namely wear of the prosthetic material (9.8% annual rate) being the most common, followed by decementation of cement‐retained IFCDPs (2.9%), and loss of the screw access filing material of the screw‐retained IFCDPs (2.7%). The most frequently observed major complication was fracture of the prosthetic material (1.9% annual rate), followed by fracture of occlusal screw (0.3%), and fracture of framework (0.3%). The annual rate of wear of prosthetic material was 7.3% for porcelain IFCDPs (n = 19/55) and 19.4% for metal‐resin IFCDPs (n = 13/16), yielding a statistically significant difference between the 2 groups (p = 0.01). Conclusions After a mean exposure time of 5.2 years, 91.6% prosthesis survival rates were achieved (65 out of 71 IFCDPs). The most frequent minor technical complication was wear of the prosthetic material with estimated 5‐year rate of 49.0%, while the most frequent major complication was fracture of the prosthetic material with estimated 5‐year dental unit‐based rate of 9.5%. The cumulative rates for “prosthesis free of minor complications” at 5‐ and 10‐years were 60.5% (95% CI: 47.2‐71.3%) and 8.9% (95% CI: 2.9‐18.0%), respectively. The cumulative rates for “prosthesis free of major technical complications” at 5‐ and 10‐years were 85.5% (95% CI: 73.0‐92.5%) and 30.1% (95% CI: 12.0‐50.6%), respectively. Pr...

Purpose:To report the rate of technical complications and prosthesis survival in a cohort of edentulous patients treated with implant-supported fixed complete dental prostheses (IFCDPs) after a mean observation period of at least 1 year. Materials and Methods: The single-visit examination included clinical and radiographic assessment, occlusal analysis, photographs and questionnaire assessing patient satisfaction in a cohort of 52 patients rehabilitated with 71 IFCDPs (supported by 457 implants). The IFCDPs were assessed for technical complications, number of implants and cantilever extension, retention type and prosthetic material type. Comparison was made between ceramic IFCDPs (Group 1) and metal-resin IFCDPs (Group 2). Kaplan-Meier survival curve analysis was carried out for assessment of prosthesis survival and was done for both Groups 1 and 2 separately. The Cox proportional hazard model was used for survival analysis, adjusting for a number of potential confounders, to evaluate the association between prosthesis survival and several risk factors such as type of opposing occlusion, nightguard use, and presence of bruxism. Responses to patient satisfaction questions were compared with Fisher's exact test. Results: Out of 71 edentulous arches (52 patients) restored with IFCDPs, 6 IFCDPs had failed, yielding a cumulative prosthesis survival rate of 91.6 % after a mean observation period of 5.2 years (range: 1-12 years) after definitive prosthesis insertion. Three IFCDPs were lost due to implant failures after 5.8 to 11 years of functional loading. Additionally, 3 metal-resin IFCDPs failed due to technical complications. Minor complications were the most frequent complications observed, namely wear of the prosthetic material (9.8% annual rate) being the most common, followed by decementation of cement-retained IFCDPs (2.9%), and loss of the screw access filing material of the screw-retained IFCDPs (2.7%). The most frequently observed major complication was fracture of the prosthetic material (1.9% annual rate), followed by fracture of occlusal screw (0.3%), and fracture of framework (0.3%). The annual rate of wear of prosthetic material was 7.3% for porcelain IFCDPs (n = 19/55) and 19.4% for metal-resin IFCDPs (n = 13/16), yielding a statistically significant difference between the 2 groups (p = 0.01). Conclusions: After a mean exposure time of 5.2 years, 91.6% prosthesis survival rates were achieved (65 out of 71 IFCDPs). The most frequent minor technical complication was wear of the prosthetic material with estimated 5-year rate of 49.0%, while the most frequent major complication was fracture of the prosthetic material with estimated 5-year dental unit-based rate of 9.5%. The cumulative rates for "prosthesis free of minor complications" at 5-and 10-years were 60.5% (95% CI: 47.2-71.3%) and 8.9% (95% CI: 2.9-18.0%), respectively. The cumulative rates for "prosthesis free of major technical complications" at 5-and 10-years were 85.5% (95% CI: 73.0-92.5%) and