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The effects of ginsenosides Rg3(R), Rg3(S) and Rg5/Rk1 (a mixture of Rg5 and Rk1, 1:1, w/w), which are components isolated from processed Panax ginseng C.A. Meyer (Araliaceae), on memory dysfunction were examined in mice using a passive avoidance test. The ginsenosides Rg3(R), Rg3(S) or Rg5/Rk1, when orally administered for 4 days, significantly ameliorated the memory impairment induced by the single oral administration of ethanol. The memory impairment induced by the intraperitoneal injection of scopolamine was also significantly recovered by ginsenosides Rg3(S) and Rg5/Rk1. Among the three ginsenosides tested in this study, Rg5/Rk1 enhanced the memory function of mice most effectively in both the ethanoland scopolamine-induced amnesia models. Moreover, the latency period of the Rg5/Rk1-treated mice was 1.2 times longer than that of the control (no amnesia) group in both models, implying that Rg5/Rk1 may also exert beneficial effects in the normal brain. We also evaluated the effects of these ginsenosides on the excitotoxic and oxidative stress-induced neuronal cell damage in primary cultured rat cortical cells. The excitotoxicity induced by glutamate or N-methyl-D-aspartate (NMDA) was dramatically inhibited by the three ginsenosides. Rg3(S) and Rg5/Rk1 exhibited a more potent inhibition of excitotoxicity than did Rg3(R). In contrast, these ginsenosides were all ineffective against the H2O2- or xanthine/xanthine oxidase-induced oxidative neuronal damage. Taken together, these results indicate that ginsenosides Rg3(S) and Rg5/Rk1 significantly reversed the memory dysfunction induced by ethanol or scopolamine, and their neuroprotective actions against excitotoxicity may be attributed to their memory enhancing effects.

Artificial intelligence (AI) is gradually influencing every aspect of everyday life, including education. AI can also provide special support to learners through academic sustainability or discontinuation predictions. While AI research remains in its early stages, we must examine how it evolves and exerts its potential over time. By utilizing AI in physical education (PE), we can increase its potential use in sports applications, and enact changes upon the nature of PE, its visualization, and repeatability. Based on the concept of AI and related research areas, this study explores its principles and use in PE, and presents a focused, in-depth analysis of the areas of PE technology where AI could be applied—customized PE classes, knowledge provision, learner evaluation, and learner counseling methods. Our findings highlight the expertise required for future PE teachers in applying AI. Regarding practice implications, this study addresses the topic of AI innovations affecting all life domains, including PE; it highlights AI applications’ relevance to PE technology, based on existing research; it proposes that the implications of AI for PE may apply to other educational domains; and finally, it contributes to existing literature and also shares future research prospects regarding AI applications in education and sports.

Performance of a polymer electrolyte membrane fuel cell with a Pd cathode catalyst was systemically investigated in this study. The Pd catalyst was directly formed on a gas diffusion layer by using electrodeposition (Pd/GDL). The electrodeposition formed aggregates of Pd nanoparticles on a gas diffusion layer with the preferred orientation of Pd(111) and Pd(200). In addition, the Pd aggregates mainly formed on the top surface of the gas diffusion layer. The membrane electrode assembly was fabricated with Pd/GDL as the cathode. The performance of the membrane electrode assembly was investigated by varying hot pressing parameters and back pressures, and the operating condition for the polymer electrolyte membrane fuel cell was optimized. Notably, introducing back pressure increased operating current density at 0.6 V by up to 45%. Durability of the membrane electrode assembly was also examined. Negligible deterioration of surface morphology of the Pd catalyst was observed even after accelerated stress testing, except for a slight increase in particle size. The results indicate that deterioration of the Pd cathode catalyst was not a major factor affecting overall single-cell performance degradation.

We induced experimental renal arterial embolization with the radiopaque solution of ethanol and iodized oil (Lipiodol) in 35 rabbits to evaluate the capability of the mixture to induce renal ablation. Serial renal angiography and plain abdominal radiography were performed immediately, one week and two weeks after embolization. Neither pure Lipiodol nor a 50% ethanol solution caused renal embolization. However, infusion of 50% and 75% ethanol-Lipiodol solutions resulted in embolization equal to that caused by absolute ethanol. The 50% ethanol-Lipiodol solution was so radiopaque that we could easily observe the embolization process during fluoroscopy. Renal arterial embolization with the 50% ethanol-Lipiodol solution was successful in three patients with hypernephroma. Our results suggest that a 50% ethanol-Lipiodol solution is radiopaque and an effective agent for renal arterial embolization.

This paper aims to empirically analyze the difference in the closure rate of the commercial district according to the industry structure of the commercial district. Theoretically, the larger the number of stores in a commercial district, the greater the positive externality caused by the agglomeration economies in consumption, namely, the external economies of scale. However, the agglomeration economies could occur from comparison shopping or one-stop shopping, depending on the business structure of the commercial district. According to the empirical results of the regression analysis of all 1164 commercial districts in Korea, the more specialized a commercial district is by stores in a specific industry, the lower the closure rate of that commercial district. This means that the agglomeration economies in consumption are driven by comparison shopping rather than by one-stop shopping and implies that it is necessary to introduce incentives that allow stores in the same industry to cluster together in terms of policy. Meanwhile, if the closure is limited to a specific industry, it will cause an endogeneity problem since it affects the industry structure of the commercial district. Considering this, as a result of additional estimation by 2SLS and GMM using instrumental variables, the error in estimation due to the endogeneity problem was not large, confirming that COVID-19 corresponds to an overall external shock that is not limited to a specific industry. In addition, this paper presents diagnostic indicators for commercial districts to measure the impact of COVID-19. Through this, it will be possible to alleviate conflicts between social classes over compensation or subsidies for sanctions for quarantine. To the best of our knowledge, it is the first time to use all commercial districts in Korea for a research in evaluating the impact of COVID-19, and empirical results on agglomeration economies focusing on the consumption side are limited.

The South Korean government currently designates toluene as a hazardous chemical, only limiting its use in products that are feared to be harmful. Since no measures to prohibit the use of toluene have been implemented, toluene is frequently detected in amounts that exceed the limit. Accordingly, the Government is considering implementing a plan to tighten the current regulations related to the use of toluene to prevent the occurrence of diseases caused by exposure and addiction to it. Therefore, the most important objective of this research is to evaluate quantitatively the economic benefits arising from the implementation of the plan in South Korea. To achieve the purpose of this paper, contingent valuation, an economic technique for analyzing data collected from a survey of people based on economic theory, is applied. For this purpose, a survey of 1000 people nationwide is conducted, and an analysis model that is well received in the literature is adopted. In other words, the annual willingness to pay (WTP) per household to strengthen the regulations to reduce the human health risks of toluene is evaluated to calculate its economic benefits. All the estimated WTP models secure statistical significance. The average WTP per household per annum is derived as KRW 3394 (USD 3.02). Considering that the country contained 20,573,060 households in 2021, the national economic benefits are calculated as KRW 69.82 billion (USD 62.23 million) every year. It is difficult to estimate accurately the costs incurred by tightening the regulations on toluene use, but they do not seem to exceed the benefits. Because tightening the regulations would be socially desirable, the Government would be justified in making this decision.

Abstract Background Generally, bacteria have a circular genome with a single replication origin for each replicon, whereas archaea and eukaryotes can have multiple replication origins in a single chromosome. In Escherichia coli, bidirectional DNA replication is initiated at the origin of replication (oriC) and arrested by the 10 termination sites (terA–J). Results We constructed E. coli derivatives with additional or ectopic replication origins, which demonstrate the relationship between DNA replication and cell physiology. The cultures of E. coli derivatives with multiple replication origins contained an increased fraction of replicating chromosomes and the cells varied in size. Without the original oriC, E. coli derivatives with double ectopic replication origins manifested impaired growth irrespective of growth conditions and enhanced cell size, and exhibited excessive and asynchronous replication initiation. The generation time of an E. coli strain with three replication origins decreased in a minimal medium supplemented with glucose as the sole carbon source. As well as cell growth, the introduction of additional replication origins promoted increased biomass production. Conclusions Balanced cell growth and physiological stability of E. coli under rapid growth condition are affected by changes in the position and number of replication origins. Additionally, we show that, for the first time to our knowledge, the introduction of replication initiation sites to the chromosome promotes cell growth and increases protein production.

High aggression is common and costly for mental health problems in young adults. Because communication is a universal part of social relationships, including conflicts with others, it could be a possible target for mediating aggression. This study aimed to evaluate whether the virtual reality (VR)-based communication modification program can be utilized for aggression management. Fifty-eight individuals with high aggression (n = 30) and with low aggression (n = 28) completed psychological assessments associated with aggression and functional communication, and they participated in the program, consisting of the three tasks: exploring the communication style, practicing functional communication, and expressing empathy. The participants’ selections and their visual analog scale scores, in response to questions in the tasks, were collected as behavioral data. Results indicated that the high aggression group selected blaming dysfunctional communication style more frequently than the low aggression group. VR-based parameters, expected to reflect dysfunctional communication-related characteristics, showed significantly different correlations with aggression-related traits between the two groups. These findings show that our program may accurately represent an individual’s aggressive traits and elicit the appropriate reaction.