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Increasing the capacity of Li-ion batteries is one of the critical issues that must be addressed. A thick and dense electrode using an active material sintered disk is expected to have a high capacity because the volume of the active material is 100% in the cathode. This study focused on LiCoO2, the most well-known active material for the cathode, to improve the properties of the sintered cathode. We investigated the impact of excess Li on various properties. We found that the degree of c-axis orientation in the sintered disk decreased as excess Li increased. In addition, results of 7Li-MAS-NMR suggest the presence of defects resulting from excess Li when the Li excess reached 5.1% or more. The discharge capacity of the LiCoO2 sintered cathode increased as the amount of excess Li increased, and a maximum discharge capacity of 11.2 mA h cm−2 was obtained when the Li excess amount was 7.3%. This result was attributed to the significant improvement in the Li-ion conductivity of LiCoO2 by both the decrease in the degree of c-axis orientation and the introduction of defects due to excess Li. Notably, introducing defects derived from excess Li enhances the Li-ion conductivity. Thus, tuning the amount of excess Li for the LiCoO2 sintered cathode was crucial in enhancing its electrochemical performance as an electrode. [ABSTRACT FROM AUTHOR]

Recently, a new oxide-type solid electrolyte (SE) for all-solid-state Li ion batteries, pyrochlore-type Li2−xLa(1+x)/3Nb2O6F (LLNOF), was reported to exhibit a Li+ superionic conductivity of 3.9 × 10−3 S cm−1 at room temperature. To gain understanding of this novel SE, in this work, thermodynamic analysis and ab initio molecular dynamics (AIMD) calculations based on the density functional theory (DFT) framework were performed to clarify the material's phase stability, electrochemical stability and Li+ ion transport properties. LLNOF is predicted to be a metastable phase, and thus, its electrochemical window is likely to be determined by its decomposition phases. The Li transport pathway is revealed to be defined by the large hexagonal tunnels formed by corner-sharing NbO6 units. These tunnels can either be La-free or La-blocked depending on the Li/La/vacancy configuration. The Li+ ion conduction mechanism proceeds in a concerted migration manner in the 16d sites via an intermediate site. Analysis of phonon density of states shows that F atoms have a lower phonon-energy band center position than O atoms; this is correlated with the characteristically low phonon-energy band center position of Li atoms and the observed Li+ superionic conductivity of LLNOF. [ABSTRACT FROM AUTHOR]

Background and Aim: We aimed to elucidate the feasibility of endoscopic resection (ER) for salvage and metachronous lesions following chemoradiotherapy (CRT) and radiotherapy (RT) for laryngopharyngeal cancer. Methods: Consecutive patients who underwent ER for superficial laryngopharyngeal cancer between March 2005 and September 2022 were retrospectively reviewed and stratified into salvage (16 patients, 16 lesions), metachronous (18 patients, 27 lesions), and naïve RT (217 patients, 306 lesions) groups. Salvage lesions were residual or local recurrent after CRT, and metachronous lesions were second primary lesions in the irradiated field following complete response. Short‐term outcomes were evaluated, including R0 resection, en bloc resection, procedure time, adverse events, local recurrence rate, and clinical course. Results: The en bloc resection rates were 88%, 93%, and 88%; R0 resection rates were 50%, 52%, and 56%; procedure times were 25, 27, and 25 min, in the salvage, metachronous, and naïve RT groups, none of which were significantly different among the three groups. Although adverse event rates tended to be higher in the salvage and metachronous groups than in the naïve RT group, the differences were not significant (18%, 15%, and 8%). The cumulative local recurrence rates at 2 years were 21%, 13%, and 6%, significantly higher in the salvage group than in the naïve RT group. The local control rates with ER alone were 94%, 93%, and 97%; none were significantly different among the three groups. Conclusion: ER for salvage and metachronous superficial lesions can be safely performed, suggesting its acceptability as a minimally invasive treatment. [ABSTRACT FROM AUTHOR]

Objectives: Endoscopic hand suturing (EHS) is a novel technique for closing a mucosal defect after endoscopic submucosal dissection (ESD). We investigated the technical feasibility of colorectal EHS using a modified flexible through‐the‐scope needle holder. Methods: This was a prospective multicenter study conducted at two referral centers between June 2022 and April 2023. This study included colorectal neoplasms 20–50 mm in size located in the sigmoid colon or rectum. A modified flexible through‐the‐scope needle holder, with an increased jaw width to facilitate needle grasping, was used for colorectal EHS. The primary end‐points were sustained closure rate on second‐look endoscopy (SLE) performed on postoperative days 3–4 and suturing time for colorectal EHS. Secondary end‐points included complete closure rate and delayed adverse events. Results: We enrolled 20 colorectal neoplasms in 20 patients, including four patients receiving antithrombotic agents. The tumor location was as follows: lower rectum (n = 8), upper rectum (n = 2), rectosigmoid colon (n = 4), and sigmoid colon (n = 6), and the median mucosal defect size was 37 mm (range, 21–65 mm). The complete closure rate was 90% (18/20 [95% confidence interval (CI) 68.3–98.8%]), and the median suturing time was 49 min (range, 23–92 min [95% CI 35–68 min]). Sustained closure rate on SLE was 85% (17/20 [95% CI 62.1–96.8%]). No delayed adverse events were observed. Conclusion: EHS demonstrated a high sustained closure rate. Given the long suturing time and technical difficulty, EHS should be reserved for cases with a high risk of delayed adverse events. [ABSTRACT FROM AUTHOR]

Objectives: There are several types of colorectal cancer (CRC) according to the detection methods and intervals, including interval CRC (iCRC) and postcolonoscopy CRC (PCCRC). We aimed to examine their proportions and characteristics. Methods: We conducted a multicenter prospective study using questionnaires in Japan ("C‐DETECT study"), in which differences in CRC characteristics according to detection methods and intervals were examined from consecutive adult patients. Because the annual fecal immunochemical test (FIT) was used in population‐based screening, the annual FIT‐iCRC was assessed. Results: In total, 1241 CRC patients (1064 with invasive CRC) were included. Annual FIT‐iCRC (a), 3‐year PCCRC (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these (a, b, c) and other CRCs (d) demonstrated differences in the proportions of ≥T2 invasion ([a] 58.9%, [b] 44.8%, [c] 87.5%, [d] 73.0%), metastasis ([a] 33.9%, [b] 21.8%, [c] 54.2%, [d] 43.9%), right‐sided CRC ([a] 42.9%, [b] 40.2%, [c] 18.8%, [d] 28.6%), and female sex ([a] 53.6%, [b] 49.4%, [c] 27.1%, [d] 41.6%). In metastatic CRC, (a) and (b) showed a higher proportions of BRAF mutations ([a] [b] 12.0%, [c] [d] 3.1%). Conclusions: Annual FIT‐iCRC and 3‐year PCCRC existed in nonnegligible proportions. They were characterized by higher proportions of right‐sided tumors, female sex, and BRAF mutations. These findings suggest that annual FIT‐iCRC and 3‐year PCCRC may have biological features different from those of other CRCs. [ABSTRACT FROM AUTHOR]

Background and Aim: Hot snare excision using electrocautery is widely used for large colorectal polyps (>10 mm); however, adverse events occur due to deep thermal injury. Colorectal polyps measuring 10–14 mm rarely include invasive cancer. Therefore, less invasive therapeutic options for this size category are demanding. We have developed hot snare polypectomy with low‐power pure‐cut current (LPPC HSP), which is expected to contribute to less deep thermal damage and lower risk of adverse events. This study aimed to evaluate the efficacy and safety of LPPC HSP for 10–14 mm colorectal polyps, compared with conventional endoscopic mucosal resection (EMR). Methods: In this multicenter, retrospective, observational study, clinical outcomes of EMR and LPPC HSP for 10–14 mm nonpedunculated colorectal polyps between January 2021 and March 2022 were compared using propensity score matching. Results: We identified 203 EMR and 208 LPPC HSP cases. After propensity score matching, the baseline characteristics between the groups were comparable, with 120 pairs. The en bloc and R0 resection rates were not significantly different between EMR and LPPC HSP groups (95.8% vs 97.5%, P = 0.72; 90.0% vs 91.7%, P = 0.82). The rates of delayed bleeding and perforation did not differ between the groups. Conclusions: Compared with conventional EMR, LPPC HSP showed a similar resection ability without an increase in adverse events. These results suggest that LPPC HSP is a safe and effective treatment for 10–14 mm nonpedunculated colorectal polyps. [ABSTRACT FROM AUTHOR]

Background and Aim: Tip‐in endoscopic mucosal resection (EMR) has a high en bloc resection rate for large colorectal neoplasms. However, non‐experts' performance in Tip‐in EMR has not been investigated. We investigated whether Tip‐in EMR can be achieved effectively and safely even by non‐experts. Methods: This retrospective study included consecutive patients who underwent Tip‐in EMR for 15–25 mm colorectal nonpedunculated neoplasms at a Japanese tertiary cancer center between January 2014 and December 2020. Baseline characteristics, treatment outcomes, learning curve of non‐experts, and risk factors of failing self‐achieved en bloc resection were analyzed. Results: A total of 597 lesions were analyzed (438 by experts and 159 by non‐experts). The self‐achieved en bloc resection (69.8% vs 88.6%, P < 0.001) and self‐achieved R0 resection (58.3% vs 76.5%, P < 0.001) rates were significantly lower in non‐experts with <10 cases of experience than in experts, but not in non‐experts with >10 cases. Adverse event (P = 0.165) and local recurrence (P = 0.892) rates were not significantly different between experts and non‐experts. Risk factors of failing self‐achieved en bloc resection were non‐polypoid morphology (OR 3.4, 95% CI 1.6–7.3, P = 0.001), lesions with an underlying semilunar fold (OR 3.6, 95% CI 1.6–7.3, P < 0.001), positive non‐lifting sign (OR 3.1, 95% CI 1.2–8.0, P = 0.023), and non‐experts with an experience of ≤10 cases (OR 3.6, 95% CI 2.1–6.3, P < 0.001). Conclusion: The clinical outcomes of Tip‐in EMR for 15–25 mm lesions performed by non‐experts were favorable. [ABSTRACT FROM AUTHOR]

Background and Aim: Computer‐aided detection (CADe) systems can efficiently detect polyps during colonoscopy. However, false‐positive (FP) activation is a major limitation of CADe. We aimed to compare the rate and causes of FP using CADe before and after an update designed to reduce FP. Methods: We analyzed CADe‐assisted colonoscopy videos recorded between July 2022 and October 2022. The number and causes of FPs and excessive time spent by the endoscopist on FP (ET) were compared pre‐ and post‐update using 1:1 propensity score matching. Results: During the study period, 191 colonoscopy videos (94 and 97 in the pre‐ and post‐update groups, respectively) were recorded. Propensity score matching resulted in 146 videos (73 in each group). The mean number of FPs and median ET per colonoscopy were significantly lower in the post‐update group than those in the pre‐update group (4.2 ± 3.7 vs 18.1 ± 11.1; P < 0.001 and 0 vs 16 s; P < 0.001, respectively). Mucosal tags, bubbles, and folds had the strongest association with decreased FP post‐update (pre‐update vs post‐update: 4.3 ± 3.6 vs 0.4 ± 0.8, 0.32 ± 0.70 vs 0.04 ± 0.20, and 8.6 ± 6.7 vs 1.6 ± 1.7, respectively). There was no significant decrease in the true positive rate (post‐update vs pre‐update: 95.0% vs 99.2%; P = 0.09) or the adenoma detection rate (post‐update vs pre‐update: 52.1% vs 49.3%; P = 0.87). Conclusions: The updated CADe can reduce FP without impairing polyp detection. A reduction in FP may help relieve the burden on endoscopists. [ABSTRACT FROM AUTHOR]

Background and Aim: Hot snare polypectomy using blend or coagulation current is widely used; however, it causes deeper tissue heat injury, leading to adverse events. We hypothesized that hot polypectomy using low‐power pure cut current (PureCut, effect 1 10 W) could reduce deeper tissue heat injury. We conducted animal experiments to evaluate the deeper tissue heat injury and conducted a prospective clinical study to examine its cutting ability. Methods: In a porcine rectum, hot polypectomy using Blend current (EndoCut, effect 3 40 W) and low‐power pure cut current was performed. The deepest part of heat destruction and thickness of the non‐burned submucosal layer were evaluated histologically. Based on the results, we performed low‐power pure cut current hot polypectomy for 10–14 mm adenoma. The primary endpoint was complete resection defined as one‐piece resection with negative for adenoma in quadrant biopsies from the defect margin. Results: In experiments, all low‐power pure‐cut resections were limited within the submucosal layer whereas blend current resections coagulated the muscular layer in 13% (3/23). The remaining submucosal layer was thicker in low‐power pure cut current than in blend current resections. In the clinical study, low‐power pure‐cut hot polypectomy removed all 100 enrolled polyps. For 98 pathologically neoplastic polyps, complete resection was achieved in 84 (85.7%, 95% confidence interval, 77–92%). The lower limit of the 95% confidence interval was not more than 15% below the pre‐defined threshold of 86.6%. No severe adverse events occurred. Conclusions: A novel low‐power pure‐cut hot polypectomy may be feasible for adenoma measuring 10–14 mm. (UMIN000037678). [ABSTRACT FROM AUTHOR]

Understanding Li diffusion at interfaces in solid-state Li batteries is essential to improving their performance (e.g., rate capabilities and energy densities). However, the visualization of Li diffusion at grain boundaries has been impossible due to the lack of experimental techniques. In this study, we visualize Li-ion diffusion at grain boundaries via secondary ion mass spectrometry at low temperatures (≈−110 °C) using an isotope exchange technique for perovskite-type Li0.29La0.57TiO3 as a model solid electrolyte. The grain boundary diffusion coefficient obtained in this study is 1.4 × 10−13 cm2 s−1 at 25 °C, which is much smaller than the bulk diffusion coefficient of 2.6 × 10−8 cm2 s−1. The long-range effective diffusion coefficients can be explained well by a 1D model based on a series of bulk and grain boundaries. The Haven ratio of grain boundary diffusion suggests that correlation between the Li+ ions is crucial for grain boundary diffusion. [ABSTRACT FROM AUTHOR]