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Li‐rich rocksalt oxides are promising cathode materials for lithium‐ion batteries due to their large capacity and energy density, and their ability to use earth‐abundant elements. The excess Li in the rocksalt, needed to achieve good Li transport, reduces the theoretical transition metal redox capacity and introduces a labile oxygen state, both of which lead to increased oxygen oxidation and concomitant capacity loss with cycling. Herein, it is demonstrated that substituting the labile oxygen in Li‐rich cation‐disordered rocksalt materials with a vacancy is an effective strategy to inhibit oxygen oxidation. It is found that the oxygen vacancy in cation‐disordered lithium manganese oxide favors high Li coordination thereby reducing the concentration of unhybridized oxygen states, while increasing the theoretical Mn capacity. It is shown that in the vacancy‐containing compound, synthesized by ball milling, the Mn valence is lowered to less than +3, providing access to more than 300 mAh g−1 capacity from the Mn2+/Mn4+ redox reservoir. The increased transition metal redox and decreased O oxidation are found to improve the capacity and voltage retention, indicating that oxygen vacancy creation to remove the most vulnerable oxygen ions and reduce transition metal valence provides a new opportunity for the design of high‐performance Li‐rich rocksalt cathodes.

Abstract We aimed to develop a novel prediction model for early neurological deterioration (END) based on an interpretable machine learning (ML) algorithm for atrial fibrillation (AF)-related stroke and to evaluate the prediction accuracy and feature importance of ML models. Data from multicenter prospective stroke registries in South Korea were collected. After stepwise data preprocessing, we utilized logistic regression, support vector machine, extreme gradient boosting, light gradient boosting machine (LightGBM), and multilayer perceptron models. We used the Shapley additive explanation (SHAP) method to evaluate feature importance. Of the 3,213 stroke patients, the 2,363 who had arrived at the hospital within 24 h of symptom onset and had available information regarding END were included. Of these, 318 (13.5%) had END. The LightGBM model showed the highest area under the receiver operating characteristic curve (0.772; 95% confidence interval, 0.715–0.829). The feature importance analysis revealed that fasting glucose level and the National Institute of Health Stroke Scale score were the most influential factors. Among ML algorithms, the LightGBM model was particularly useful for predicting END, as it revealed new and diverse predictors. Additionally, the effects of the features on the predictive power of the model were individualized using the SHAP method.

5-Hydroxymethylfurfural (HMF) has aroused considerable interest over the past years as an important biomass-derived platform molecule, yielding various value-added products. The conventional HMF conversion requires noble metal catalysts and harsh operating conditions. On the other hand, the electrocatalytic conversion of HMF has been considered as an environmentally benign alternative. However, its practical application is limited by low overall energy efficiency and incomplete conversion. Paired electrolysis and highly efficient electrocatalysts are two viable strategies to address these limitations. Herein, an overview of coupled electrocatalytic HMF hydrogenation or hydrogen evolution reaction (HER) with HMF oxidation as well as the associated electrocatalysts are reviewed and discussed. In this mini-review, a brief introduction of electrocatalytic HMF upgrading is given, followed by the recent advances and challenges of paired electrolysis with an emphasis on the integration HMF electrohydrogenation with HMF electrooxidation. Finally, a perspective for a future sustainable biomass upgrading community based on electrocatalysis is proposed.

Background Unlike patients with stroke caused by other mechanisms, the effect of elevated plasma total homocysteine (tHcy) on the prognosis of patients with both ischemic stroke and atrial fibrillation (AF) is unknown. This study aimed to evaluate the association between tHcy level and the functional outcome of patients with AF‐related stroke. Methods and Results We included consecutive patients with AF‐related stroke between 2013 and 2015 from the registry of a real‐world prospective cohort from 11 large centers in South Korea. A 3‐month modified Rankin Scale score ≥3 was considered an unfavorable outcome. Since tHcy is strongly affected by renal function, we performed a subgroup analysis according to the presence of renal dysfunction. A total of 910 patients with AF‐related stroke were evaluated (mean age, 73 years; male sex, 56.0%). The mean tHcy level was 11.98±8.81 μmol/L. In multivariable analysis, the tHcy level (adjusted odds ratio, 1.04; 95% CI, 1.01–1.07, per 1 μmol/L) remained significantly associated with unfavorable outcomes. In the subgroup analysis based on renal function, tHcy values above the cutoff point (≥14.60 μmol/L) showed a close association with the unfavorable outcome only in the normal renal function group (adjusted odds ratio, 3.10; 95% CI, 1.60–6.01). In patients with renal dysfunction, tHcy was not significantly associated with the prognosis of AF‐related stroke. Conclusions A higher plasma tHcy level was associated with unfavorable outcomes in patients with AF‐related stroke. This positive association may vary according to renal function but needs to be verified in further studies.

Background Despite the recent acceptance of thrombectomy as the standard of care in patients with acute anterior circulation stroke, the benefits of thrombectomy remain uncertain for patients with acute basilar artery occlusion (BAO). This study aimed to evaluate the effectiveness and safety of thrombectomy and to identify predictors of outcomes in a large cohort of patients with acute BAO. Methods and Results This study included 212 consecutive patients with acute BAO who underwent either stent‐retriever or contact aspiration thrombectomy as the first‐line approach between January 2011 and August 2017 at 3 stroke centers. Clinical and radiologic data were prospectively collected and stored in a database at each center. Multivariable ordinal logistic regression was performed to assess the association between each characteristic and 90‐day modified Rankin scale scores. Reperfusion was successful in 91.5% (194/212) of patients; 44.8% (95/212) of patients achieved 90‐day modified Rankin scale 0 to 2. The symptomatic hemorrhage rate was 1.9% (4/212) and mortality was 16% (34/212). In a multivariable ordinal regression, younger age, lower National Institute of Health stroke scale on admission, and absence of diabetes mellitus and parenchymal hematoma were significantly associated with a favorable shift in the overall distribution of 90‐day modified Rankin scale scores. Treatment outcomes were similar between patients who received stent‐retriever thrombectomy and contact aspiration thrombectomy as the first‐line technique. Conclusions Endovascular thrombectomy was effective and safe for treating patients with acute BAO. Age, the baseline National Institute of Health stroke scale, diabetes mellitus, and parenchymal hematoma were associated with better outcomes. This study showed no superiority of the stent‐retriever over the aspiration thrombectomy for treating acute BAO.

BACKGROUND AND PURPOSE: Acute intracranial occlusion can be associated with in situ thrombo-occlusion in relation to preexisting intracranial atherosclerotic disease. We aimed to assess residual stenosis at the site of a target arterial lesion (TAL) to determine whether residual stenosis at the TAL is associated with underlying intracranial atherosclerotic disease. METHODS: One hundred and sixty-three patients who underwent endovascular therapy for M1 middle cerebral artery occlusion and achieved angiographic reperfusion were selected for analysis. The presence of residual stenosis at the TAL was classified using the Arterial Occlusive Lesion (AOL) scale at postprocedural angiography, and the severity of stenosis was grouped into none, mild (

The coronavirus, which first appeared in December 2019, has had a great economic and social impact not only on the world but also on Korea as of 2024, and has a great impact on the cultural and artistic fields. This study was conducted to identify the perception of online non-face-to-face arts and physical education practical training among the fields of arts and culture education and to suggest directions for online arts education. To this end, online big data was collected based on the keywords of 'art education', 'culture and art performance', and 'art and physical training', and after purification/morphological analysis of the collected data, text mining, matrix analysis, discourse analysis, Network analysis and sentiment analysis were performed. The big data collection of online arts and physical training was done through portals and SNS, and was targeted at Naver, Daum, Google, YouTube, and Twitter. The period consisted of 7,837 data from March 2022 to March 2023 to investigate the general public's perception of arts education after the COVID-19 pandemic. This study is expected to be a basic material to present the direction of online education for art culture by analyzing the perceptions of art majors as well as ordinary people interested in art and physical education through big data. [ABSTRACT FROM AUTHOR]