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Novel production process for lithium sulfide from lithium hydroxide by reacting with hydrogen sulfide gas generated from iron sulfide
No full textThe efficient production of lithium sulfide (Li2S), a key raw material for sulfide electrolytes in all-solid-state batteries, is important owing to its high cost. In this study, an efficient method for producing high-purity Li2S by the reaction between lithium hydroxide (LiOH) and hydrogen sulfide (H2S) gas was investigated. The study used H2S gas generated from the dissolution of iron sulfide (FeS) in a sulfuric acid (H2SO4) solution at 298 K. When reactions between LiOH and the generated H2S gas were performed at 373–673 K for 1 h, Li2S was obtained. Notably, the generation of sulfur was observed when the reaction temperature was above 573 K. Based on the experimental results and thermodynamic analysis, the principle of Li2S production by the reaction of LiOH with H2S gas is described. This study suggests the feasibility of the direct production of Li2S from LiOH by reacting H2S gas and the utilization of FeS as a source of H2S gas to reduce its environmental impact.N
Automated and Efficient Sampling of Chemical Reaction Space
No full textMachine learning interatomic potentials (MLIPs) promise quantum-level accuracy at classical force field speeds, but their performance hinges on the quality and diversity of training data. An efficient and fully automated approach to sample chemical reaction space without relying on human intuition, addressing a critical gap in MLIP development is presented. The method combines the speed of tight-binding calculations with selective high-level refinement, generating diverse datasets that capture both equilibrium and reactive regions of potential energy surfaces. By employing single-ended growing string and nudged elastic band methods, reaction pathways previously underrepresented in MLIP training sets, particularly near transition states are systematically explored. This approach yields datasets with rich structural and chemical diversity, essential for robust MLIP development. Open-source code is provided for the entire workflow, facilitating the integration of the approach into existing MLIP development pipelines.Y
Timber resources and management characteristics of economic forestry management areas and other forests in South Korea: post-reforestation challenges
No full textOver the past 50 years South Korea has made considerable strides in economic development and reforestation by converting barren land into dense forests. Despite these achievements, the forestry sector still faces significant challenges in economic viability and resource utilization. Economic Forestry Management Areas (EFMAs) were established to enhance sustainable timber production and address these challenges. This study evaluates the effectiveness of EFMAs in comparison to other forest areas, focusing on timber resources and management characteristics. The findings reveal that, although EFMAs show a higher intensity of management operations than other forest areas, improvements in timber quality and productivity remain limited. This highlights an important insight: despite increased management efforts, substantial progress in enhancing the quality and quantity of timber resources has not yet been achieved. This outcome may be attributed to the relatively short time since EFMAs were first established, which has not allowed sufficient time for significant developments in timber resource enhancement. To address these challenges, this study recommends increasing the proportion of economically valuable coniferous species and expanding artificial forest coverage through well-coordinated reforestation and management efforts. Additionally, developing precise, location-specific management data is crucial to avoid overlapping activities and to enhance the efficiency of forest management. These strategic improvements will not only boost the productivity of EFMAs but also support sustainable forestry practices, facilitating South Korea's transition into the post-reforestation era.Y
Transforming TGF-β suppression into IL-15 stimulation: Advancing engineered CAR-T therapy for solid tumors
No full textN
The inverse optimal value problem for linear fractional programming
No full textWe study the inverse optimal value problem for linear fractional programming, where the goal is to find the coefficients of the fractional objective function such that the resulting optimal objective function value is as close as possible to some given target value. We show that this problem is NP-hard. Then, we provide some structural results, which are exploited to derive several reformulations and two solution algorithms. The proposed approaches are based on the Charnes-Cooper and parametric transformations.N
Comparative Effectiveness of Rosuvastatin Versus Atorvastatin in Acute Ischemic Stroke Treatment
No full textBackground Research specifically addressing the efficacy of rosuvastatin versus atorvastatin in patients with ischemic stroke is insufficient. Using a large stroke registry, we investigated whether 2 commonly used statins, rosuvastatin and atorvastatin, differ in their effectiveness in reducing the risk of vascular events in patients with acute ischemic stroke.Methods We analyzed data from a nationwide stroke registry in South Korea between January 2011 and April 2022. Patients with acute ischemic stroke within 7 days of onset who were prescribed either atorvastatin or rosuvastatin at discharge were included. The primary outcome was a composite of recurrent stroke (either hemorrhagic or ischemic), myocardial infarction, and all-cause mortality within 1 year.Results A total of 43 512 patients (age, 69.2 +/- 12.5 years; male, 59.8%) were analyzed in this study. Atorvastatin was used in 84.8% (n=36 903), and rosuvastatin was used in 15.2% (n=6609). The 1-year cumulative event rate of the composite of recurrent stroke, myocardial infarction, and all-cause mortality was significantly lower in the rosuvastatin group than in the atorvastatin group (9.7% [95% CI, 9.0-10.5] versus 10.7% [95% CI, 10.4-11.0]; P=0.049). Cox proportional hazards analysis revealed that rosuvastatin, compared with atorvastatin, was significantly associated with less risk of 1-year composite of recurrent stroke, myocardial infarction, and all-cause mortality, with an absolute risk reduction of 1% [95% CI, -1.8 to -0.2] and a relative risk reduction of 11% (hazard ratio, 0.89 [95% CI, 0.82-0.97]). However, there were discrepancies in the statistical significance of the results between the propensity score matching and stabilized inverse probability of treatment weighting analysis.Conclusions The results of this analysis of a large cohort of patients with ischemic stroke suggested that, compared with atorvastatin, rosuvastatin was significantly associated with a reduced risk of a 1-year composite of recurrent stroke, myocardial infarction, and all-cause mortality in patients with acute ischemic stroke. However, in real clinical practice, rosuvastatin is used less than one-fifth as frequently as atorvastatin in patients with acute ischemic stroke. This study serves as a hypothesis-generating function.Y
Loneliness, Social Isolation, and Digital Health Literacy Among Older Women Living Alone in South Korea During the COVID-19 Pandemic
No full textObjective While using digital technologies for social health is widely acknowledged, the relationship between loneliness, social isolation, and digital health literacy remains unknown. This study aimed to assess the levels of loneliness, social isolation, and digital health literacy in older women living alone and to explore the associations between these factors. Methods In August 2021, a cross-sectional survey was conducted on 145 older women living alone, selected using convenience sampling. The study used the University of California, Los Angeles Loneliness Scale (version 3), Lubben Social Network Scale-6, and Digital Health Technology Literacy-Assessment Questionnaire. The collected data were analyzed using descriptive statistics, the Mann-Whitney U test, the Kruskal-Wallis test, Spearman's rho correlation, and a generalized linear model (GLM). Results Of the participants, 22.8% (n=33) reported moderate loneliness, 20.7% (n=30) reported severe loneliness, and 36.6% (n=53) were at risk for social isolation. The mean digital health literacy score among participants was 4.85 (SD=6.92), which is relatively low. Importantly, our findings using a GLM to control for covariates revealed a significant association between loneliness (B=-0.013, p=0.018) and digital health literacy. Conclusion The increased loneliness experienced during the pandemic may contribute to low digital health literacy, alienating these individuals from the benefits of digital technologies. Therefore, in developing digital health programs or policies, it is imperative to consider the psychosocial status of individuals, including loneliness, while enhancing digital health literacy. Psychiatry Investig 2025;22(1):75-83N
Laser-Induced Nanowire Percolation Interlocking for Ultrarobust Soft Electronics
No full textMetallic nanowires have served as novel materials for soft electronics due to their outstanding mechanical compliance and electrical properties. However, weak adhesion and low mechanical robustness of nanowire networks to substrates significantly undermine their reliability, necessitating the use of an insulating protective layer, which greatly limits their utility. Herein, we present a versatile and generalized laser-based process that simultaneously achieves strong adhesion and mechanical robustness of nanowire networks on diverse substrates without the need for a protective layer. In this method, the laser-induced photothermal energy at the interface between the nanowire network and the substrate facilitates the interpenetration of the nanowire network and the polymer matrix, resulting in mechanical interlocking through percolation. This mechanism is broadly applicable across different metallic nanowires and thermoplastic substrates, significantly enhancing its universality in diverse applications. Thereby, we demonstrated the mechanical robustness of nanowires in reusable wearable physiological sensors on the skin without compromising the performance of the sensor. Furthermore, enhanced robustness and electrical conductivity by the laser-induced interlocking enables a stable functionalization of conducting polymers in a wet environment, broadening its application into various electrochemical devices.Y
Fundamental study on structural formation, amino acids and nucleotide-related compounds of cultivated meat from 3D-cultured pig muscle stem cells
No full textSince the first cultivated meat prototype in 2013, significant advancements have been made, yet cultivated meat still differs from conventional meat, particularly in nutritional and flavor profiles. In this study, cell-cultivated pork was developed using 3D-cultured pig muscle stem cells (MuSCs) on hydrogel scaffolds over a 44-day period and analyzed for muscle maturity and nutritional characteristics. qPCR analysis showed muscle fiber maturation with a shift from type I to type II fibers during long-term culture. Genes related to muscle structure, including MYH and TNNI isoforms, were increasingly expressed between days 9 and 16. Although cultivated pork differed significantly in total and free amino acids and nucleotide-related compounds compared to conventional pork, its total amino acid composition per protein content was comparable, if not superior. This study provides key insights into the structure, composition, and development of cultivated pork, guiding future improvements to more closely mimic traditional pork.N
Long-Term Incidence of Gastrointestinal Bleeding Following Ischemic Stroke
No full textBackground and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes. Methods We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data. Results Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2, and a 3-month modified Rankin Scale score of ≥4. Conclusion Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.Y