Homeoprotein Hbx4 represses adhesion molecule governing cytokinesis and development

Homeobox genes encode proteins with a highly conserved DNA-binding motif and provoke morphological diversification of body segments by differentially controlling the expression of downstream targets. Here, we have identified _hbx4_, one of many homeobox genes in _Dictyostelium discoideum_ and investigated its role during growth and development. In suspension, Hbx4-overexpressing cells, Hbx4^OE^, showed defects in cytokinesis and growth rate. During development, Hbx4^OE^ and _hbx4_-disrupting cells, _hbx4¯_ made differences in shape of mound and slug, cell-type proportioning from wild type KAx3 cells. These phenotypes were similar to those of mutant defective in _cadA_ encoding Ca^2+^-dependent cell adhesion molecule so that we investigated the relationship between _hbx4_ and _cadA_. Overexpression of Hbx4 inhibited the expression of _cadA_ and cAMP also failed to stimulate _cadA_ in Hbx4^OE^. Furthermore, gel mobility shift assay showed the promoter of _cadA_ contained Hbx4-binding site, indicating Hbx4 negatively regulates the expression of _cadA_. Proteome analysis revealed that overexpression of Hbx4 repressed the _rdiA_ and _abpB_ encoding rho guanine nucleotide dissociation inhibitor1, RhoGDI1 and actin bundling protein 34, ABP34, respectively. And the overexpression of _cadA_ in Hbx4^OE^ cells rescued the defects and increased mRNA level of _rdiA_, _abpB_ and one of Rho GTPase, _rac1b_. These results suggested that Hbx4 can modulate cytokinesis, cell sorting and cell-type proportioning by repressing _cadA_ that regulates GTPase-dependent signaling pathway

A Study On The Determinants Of Business Stability In Credit Card Firms: Evidence From Korea

This study empirically analyses several factors that affect financial stability such as the profitability of Korean credit card firms, capital adequacy, loan soundness, and liquidity. In particular, internal and external factors found in previous studies were applied to the analysis in order to investigate whether or not those factors had a significant effect on the business stability of Korean credit card firms. The major research findings are as follows. First, the determinant factors for profitability were found to be the degree of enlargement, foreign credibility, and the level of risk management. Second, the determinant factors for capital adequacy were found to be the degree of enlargement, diversification, foreign credibility, the level of management, and the interest rate. Third, the determinant factors for loan soundness were found to be the degree of enlargement and foreign credibility. Lastly, the determinant factors for liquidity were found to be the degree of diversification, foreign credibility, the level of risk management, the degree of competition, economic conditions, and the interest rate. In conclusion, with the recent reduction in the card affiliates’ fees, the leverage regulation, and the credit card debt suppression policy, financial authorities will likely refer to this study as they carefully examine the various influences on the business stability of domestic credit card firms and come up with relevant countermeasures for the continuous growth of those firms

Pro-Cyclicality Of Small And Medium Enterprise (Sme) Loans According To Financing Type Based On Purpose: Evidence From Korean Banks

An empirical analysis is conducted on the pro-cyclicality of SME loans based on purpose, which has not been examined in previous research. In this study, the purpose of SME loans is divided into four types: total SME loans, long-term loans for investment in equipment, long-term loans for R&D investment, and short-term loans for working capital. The aim of the study is to determine whether pro-cyclicality exists in the four types of loans. In particular, it is expected that because of the high-risk weight considered in estimating credit risk, the number of long-term loans may have decreased in the economic distress experienced since 2006, when the Basel II accord came into effect. At that time, most banks adopted the advanced internal rating approach to calculate borrowers' credit risks. This study is based on the assumption that the risk weight of long-term loans is different from that of short-term loans. The GMM model is adopted to test the pro-cyclicality of long-term and short-term loans. The test results showed signifcant pro-cyclicality in long-term loans for investment in equipment and R&D. Second, there was no pro-cyclicality in short-term loans for purchasing raw materials. Third, the fnancial characteristics affecting the lending behaviour of banks were indicators of proftability and fnancial soundness of credit. Based on the results, effective policies are recommended, such as credit enhancement through credit guarantees, in order to alleviate the effects of pro-cyclicality on long-term loan

The Effects of Group Work on Interaction and Learning Outcomes in Non Face-to-Face Synchronous General English Classes in the EFL Setting

The effects of group work with assigned roles on learner-instructor interaction (LII), learner-learner interaction (LLI), and task achievement were investigated in non-face-to-face general English classes to determine implications for non-face-to-face online group work. The participants were 128 university students in South Korea. Zoom was employed for the synchronous classes (SC), and the university’s LMS (Learning Management System) was utilized for the asynchronous classes (AC). The participants were divided into three groups: Group A were assigned designated roles in SC, Group B were not assigned specific roles in SC, and Group C were assigned designated roles in AC. The students were required to produce two English presentation videos. The participants exchanged feedback and comments about the content and structure of the presentation script. The video production and editing through group work, a pre- and post-questionnaire, and task results were employed as analysis data. The results revealed that group work in which roles were assigned had a positive effect on LII and LLI. It should be noted that group work differs from face-to-face instruction. Thus, it is imperative that techers design detailed plans in advance and monitor student participation closely. Pedagogical implications and recommendations for future studies are outlined

A Study On Dividend Determinants For Korea's Information Technology Firms

In this study, we analyse the determinants of dividend policies of information technology (IT) firms listed on the Korean stock market and use a logit regression model to examine Korean IT firms' propensity to pay dividends based on the life-cycle hypothesis. The analysis yields several findings: first, the firms pay relatively small dividends in the growth stage, which increase over time as their businesses mature. Second, profitability shows a positive correlation with propensity to pay dividends. Third, firms that paid out more dividends in the past continue to pay relatively more dividends. Meanwhile, dividend policies do not show a significant correlation with firm size or growth opportunities. In addition, dividend policies have no relation to the catering incentive (investor fads for dividends) or risk. These observations suggest that Korean IT firms' propensity to pay dividends is supported by the life-cycle hypothesis and that the declining dividends from the mid-2000s can be attributed to deteriorating profits

Impact of water on toxic hydrogen fluoride generation from the decomposition of LiPF6 in lithium-ion battery electrolytes

PresentationToxic hydrogen fluoride (HF) gas can be generated when LiPF6, a salt used in lithium-ion battery electrolytes, thermally decomposes and/or reacts with trace water. Simultaneous thermal analysis and mass spectrometry (STA-MS) was conducted on five different organic solvents containing LiPF6 to determine the temperatures at which HF is generated and the activation energies of the decomposition reaction. STA-MS allows the simultaneous direct observation of electrolyte thermal stability and hydrogen fluoride generation, something that is not possible with gas chromatography–mass spectrometry alone, thus it represents a more efficient and simple experimental approach. The five solvents tested in this study were anhydrous tetrahydrofurfuryl alcohol (THFA), 1,3- dioxolane (1,3-DL), diethyl carbonate (DEC), 1,2-dimethoxyethane (DME), and ethyl carbonate (EC). STA-MS analysis of the LiPF6 in these solvents revealed that HF generation occurred at different temperatures for each electrolyte. In the case of 1M LiPF6 in THFA, the addition of 1000 ppm of water reduced the thermal decomposition temperature compared to solid neat LiPF6. Except for EC, all of the other electrolyte systems exhibited a lower HF generation temperature and a lower reaction activation energy (Ea) when water was present. Additionally, from a risk assessment perspective, the results indicate that the HF generation starts from the SEI layer decomposition stage which occurs early in the thermal runaway mechanism of the lithium-ion battery. This research can be used to develop more thermally stable and safer electrolytes in the future, especially with respect to HF generation. In addition, this study highlights the need for research into measures to combat large-capacity lithium-ion battery fires, which may occur in electric vehicles and grid-scale energy storage systems

Observation of R600a flow at subcooled temperature conditions in a vapor compression refrigeration system

Vapor compression refrigeration system is usually designed such that refrigerant exits a condenser at subcooled liquid state in order not to cause possible damage to expansion devices. Even in small refrigeration systems incorporating capillary tube as an expansion device, the refrigerant is supposed to be subcooled before entering the expansion device. In this study, experimental apparatus equipped with several thermocouples, pressure transducers and visualization device was constructed in order to observe the behavior of refrigerant flow at condenser outlet of a vapor compression refrigeration system. Visual observation as well as temperature and pressure readings indicate the presence of two-phase flow at highly subcooled temperature. An alternative equation was suggested to calculate the enthalpy of the two-phase refrigerant in subcooled region and verification test was conducted

LFS-GAN: Lifelong Few-Shot Image Generation

We address a challenging lifelong few-shot image generation task for the first time. In this situation, a generative model learns a sequence of tasks using only a few samples per task. Consequently, the learned model encounters both catastrophic forgetting and overfitting problems at a time. Existing studies on lifelong GANs have proposed modulation-based methods to prevent catastrophic forgetting. However, they require considerable additional parameters and cannot generate high-fidelity and diverse images from limited data. On the other hand, the existing few-shot GANs suffer from severe catastrophic forgetting when learning multiple tasks. To alleviate these issues, we propose a framework called Lifelong Few-Shot GAN (LFS-GAN) that can generate high-quality and diverse images in lifelong few-shot image generation task. Our proposed framework learns each task using an efficient task-specific modulator - Learnable Factorized Tensor (LeFT). LeFT is rank-constrained and has a rich representation ability due to its unique reconstruction technique. Furthermore, we propose a novel mode seeking loss to improve the diversity of our model in low-data circumstances. Extensive experiments demonstrate that the proposed LFS-GAN can generate high-fidelity and diverse images without any forgetting and mode collapse in various domains, achieving state-of-the-art in lifelong few-shot image generation task. Surprisingly, we find that our LFS-GAN even outperforms the existing few-shot GANs in the few-shot image generation task. The code is available at Github.Comment: 20 pages, 19 figures, 14 tables, ICCV 2023 Poste