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Corporate disclosure behavior during financial crises: Evidence from Korea
No full textWe examine corporate disclosure patterns according to changes in firm states during financial crises in Korea. Using panel data on Korean listed firms from 1995 to 2019, we first confirm that they transparently (opaquely) disclose information when the change in return on assets is positive (negative) during crises. Moreover, we check that these disclosure patterns increase debt financing but are ineffective for equity financing. Finally, for chaebols with internal capital markets, we find that internal capital receivers provide transparent (opaque) disclosure of negative (positive) changes in their states. By contrast, providers show the opposite patterns. (JEL G01, G30, M40)N
Bribing Donors with International Human Rights Standing: Chinese Foreign Aid and Recommendations at the Universal Periodic Review
Get PDFWork-Parenting Gains and Strains for Dual-Earner Parents with Early Adolescent Children: Application of the Autoregressive Cross-Lagged Model (ACLM) and the Actor-Partner Interdependence Model (APIM)
No full text본 연구는 초기 청소년기 자녀를 둔 맞벌이 부모의 일-양육 양립에 대한 이점과 갈등 인식수준이 종단적으로 본인과 배우자에게 미치는 영향을 살펴보았다. 이를 위해 한국아동패널 12차(초5) ~ 14차(중1)에서 아버지와 어머니 모두 취업 중인 부모 400쌍(800명)의 응답을 자기회귀교차지연(ACLM)과 자기-상대방 상호의존모형(APIM)을 통해 분석하였다. 연구 결과 첫째, 일-양육 양립 시 이점 인식은 부모 모두 중간값보다 높은 수준이었고 어머니가 아버지보다 다소 낮았으며, 갈등인식은 부모모두 중간값보다 낮은 수준이었고 어머니가 아버지보다 다소 높았다. 둘째, 부모의 일-양육 양립 시 이점과 갈등 인식은 다음 해 본인의 인식에 정적 영향을 미쳤다. 셋째, 아버지의 일-양육 양립 시 이점 및갈등 인식은 다음 해 어머니의 인식에 영향을 미치지 않았으나, 어머니의 인식은 다음 해 아버지의 인식에 정적 영향을 미쳤다. 이러한 결과는 맞벌이 부모가 각자 인식하는 일-양육 분담 정도가 다를 수 있음을 보여주며, 부부가 서로의 조력자로서 일과 양육의 지속적 균형을 맞춰갈 수 있도록 하는 의사소통 지원의 필요성을 시사한다.N
Nonlinear dynamics of Kimchi premium
No full textKimchi premium, the persistent non -zero price difference exists between the US and Korean crypto-markets. Not only does the premium represent a violation of the law of one price but it may also reflect the bubble aspect of crypto-markets or crypto-market segmentation. Contrary to the literature relying on linear modelling, we employ threshold regression with multiple regimes to show the nonlinear dynamics of the premium and identify its determinants. We find that the premium is mean -reverting when it exceeds a certain level of thresholds but displays a random walk inside the range, which implies that only for relatively large -sized premiums, arbitrageurs exploit the premium. Kimchi premium has a non -zero long run steady-state level of 1.24% for Bitcoin aligned with the violation of the law of one price. We demonstrate that the non -zero premium exists due in part to market frictions given that the trading fee is positively correlated with the threshold.Y
Air quality and kidney health: Assessing the effects of PM 10, PM 2.5, CO, and NO 2 on renal function in primary glomerulonephritis
No full textBackground: While extensive studies have elucidated the relationships between exposure to air pollution and chronic diseases, such as cardiovascular disorders and diabetes, the intricate effects on specific kidney diseases, notably primary glomerulonephritis (GN)-an immune-mediated kidney ailment-are less well understood. Considering the escalating incidence of GN and conspicuous lack of investigative focus on its association with air quality, investigation is dedicated to examining the long-term effects of air pollutants on renal function in individuals diagnosed with primary GN. Methods: This retrospective cohort analysis was conducted on 1394 primary GN patients who were diagnosed at Seoul National University Bundang Hospital and Seoul National University Hospital. Utilizing time-varying Cox regression and linear mixed models (LMM), we examined the effect of yearly average air pollution levels on renal function deterioration (RFD) and change in estimated glomerular filtration rate (eGFR). In this context, RFD is defined as sustained eGFR of less than 60 mL/min per 1.73 m 2 . Results: During a mean observation period of 5.1 years, 350 participants developed RFD. Significantly, elevated interquartile range (IQR) levels of air pollutants-including PM 10 (particles <= 10 micrometers, HR 1.389, 95 % CI 1.2-1.606), PM 2.5 (particles <= 2.5 micrometers, HR 1.353, 95 % CI 1.162-1.575), CO (carbon monoxide, HR 1.264, 95 % CI 1.102-1.451), and NO 2 (nitrogen dioxide, HR 1.179, 95 % CI 1.021-1.361)-were significantly associated with an increased risk of RFD, after factoring in demographic and health variables. Moreover, exposure to PM 10 and PM 2.5 was associated with decreased eGFR. Conclusions: This study demonstrates a substantial link between air pollution exposure and renal function impairment in primary GN, accentuating the significance of environmental determinants in the pathology of immune-mediated kidney diseases.Y
Subseasonal Variability of ENSO-East Asia Teleconnections Driven by Tropical Convection Over the Indian Ocean and Maritime Continent
No full textThe El Ni & ntilde;o-Southern Oscillation (ENSO) has a significant impact on the surface climate of East Asia by modulating the atmospheric circulation over the Kuroshio Extension. Here, we show that the ENSO-East Asia teleconnections are strongest in early winter due to the combined effects of the Indian Ocean and Maritime Continent convections, but weakest in mid-winter as these tropical convections weaken. During the early El Ni & ntilde;o winter, convection is enhanced over the Indian Ocean and suppressed over the Maritime Continent. The associated Rossby wave trains constructively interfere over the Kuroshio Extension, resulting in anticyclonic circulation anomalies. The equatorial central Pacific convection has a minimal impact on the East Asia. This result suggests that the Indian Ocean and the Maritime Continent convections, rather than the equatorial central Pacific convection, are the precursors of the early winter ENSO-East Asia teleconnections, and need to be considered for subseasonal-to-seasonal prediction in East Asia. The El Ni & ntilde;o-Southern Oscillation (ENSO) significantly influences the winter surface climate in East Asia through atmospheric teleconnections. The ENSO teleconnections are particularly pronounced in early winter when an anomalous anticyclonic circulation developes over the Kuroshio Extension and transports warm and moist air to the East Asian continent, but weaken in mid-winter. Here, we show that such subseasonal variability of the ENSO-East Asia teleconnections is primarily determined by tropical convection over the Indian Ocean and the Maritime Continent, with a minimal impact of convection over the equatorial central Pacific where ENSO develops. The El Ni & ntilde;o-Southern Oscillation (ENSO) teleconnections show distinct subseasonal variability over East Asia, with the strongest teleconnections in early winter The ENSO-East Asia teleconnections are modulated by anomalous tropical convection over the Indian Ocean and the Maritime Continent on subseasonal time scale Rossby wave trains induced by enhanced convection over the Indian Ocean and those by suppressed convection over the Maritime Continent constructively interfere over the East Asia during the early El Ni & ntilde;o winterN
Study on the Digestion-Induced Changes in the Characteristics and Bioactivity of Korean Native and Overseas Cattle-Derived Peptides
No full textThis study was conducted to compare and analyze the changes in the biochemical characteristics and biological activity of peptide extracts derived from Chickso, Hanwoo, and Wagyu beef during digestion. The results of the in vitro digestion analysis revealed that the digestion rate, total free amino acid content, and antioxidant and antihypertensive activities of Chickso loin and shank myofibrillar proteins were significantly higher (p<0.05) than those of Hanwoo and Wagyu loin and shank myofibrillar proteins. Particularly, the peptide extracts of Chickso loin and shank had a high angiotensin-converting enzyme inhibitory activity. In mice in vivo digestion experiment, the blood serum of mice fed with Chickso loin peptide extract (<10 kDa) showed the highest antioxidant enzyme activity. Thus, Chickso peptide extracts were deemed to be similar or more bioactive than Hanwoo and Wagyu peptide extracts, and can be used as bioactive materials.Y
Laminin as a Key Extracellular Matrix for Proliferation, Differentiation, and Maturation of Porcine Muscle Stem Cell Cultivation
No full textExtracellular matrix (ECM) proteins play a crucial role in culture muscle stem cells (MuSCs). However, there is a lack of extensive research on how each of these proteins influences proliferation and differentiation of MuSCs from livestock animals. Therefore, we investigated the effects of various ECM coatings—collagen, fibronectin, gelatin, and laminin—on the proliferation, differentiation, and maturation of porcine MuSCs. Porcine MuSCs, isolated from 14-day-old Berkshire piglets, were cultured on ECM-coated plates, undergoing three days of proliferation followed by three days of differentiation. MuSCs on laminin showed higher proliferation rate than others (p < 0.05). There was no significant difference in the mRNA expression levels of PAX7, MYF5, and MYOD among MuSCs on laminin, collagen, and fibronectin (p > 0.05). During the differentiation period, MuSCs cultured on laminin exhibited a significantly higher differentiation rate, resulting in thicker myotubes compared to those on other ECMs (p < 0.05). Also, MuSCs on laminin showed higher expression of mRNA related with maturated muscle fiber such as MYH1 and MYH4 corresponding to muscle fiber type IIx and muscle fiber type IIb, respectively, compared with MuSCs on other ECM coatings (p < 0.05). In summary, our comparison of ECMs revealed that laminin significantly enhances MuSC proliferation and differentiation, outperforming other ECMs. Specifically, muscle fibers cultured on laminin exhibited a more mature phenotype. These findings underscore laminin's potential to advance in vitro muscle research and cultured meat production, highlighting its role in supporting rapid cell proliferation, higher differentiation rates, and the development of mature muscle fibers.Y
Recent Progress in High-Efficiency Transparent Vacuum Insulation Technologies for Carbon Neutrality
No full textEnhancing energy efficiency in buildings is a pivotal strategy for reducing energy consumption and mitigating greenhouse gas emissions. As part of global efforts to achieve carbon neutrality by 2050, there is a heightened focus on improving window insulation because windows are a significant source of thermal loss, representing nearly 40% of a building's heat dissipation. This study explores the development and application of vacuum insulation glazing (VIG), a cutting-edge insulation technology, to substantially reduce heat transfer through windows, thereby contributing to building energy savings. With its superior insulation performance, achieving thermal transmittance levels around 0.5W/m2 center dot K, VIG technology presents a promising advancement over traditional double-glazed or gas-filled insulating glass units (IGUs). However, the adoption of VIG is challenged by economic factors, with costs significantly higher than standard IGUs and triple-glazed windows meeting passive house standards. The production of VIG, characterized by lengthy evacuation times and high processing temperatures, contributes to its elevated price. This research identifies the potential for cost reduction through optimizing manufacturing processes, including using low-melting-point solders for hermetic sealing and localized heating techniques to shorten production times. Despite the high initial cost, the potential for integrating VIG with other smart technologies suggests a promising future for achieving carbon neutrality in buildings. The study calls for further research and standardization in VIG production to overcome current technical and economic barriers, paving the way for its wider adoption and realizing next-generation energy-efficient building materials.Y
Untethered soft actuators for soft standalone robotics
No full textSoft actuators produce the mechanical force needed for the functional movements of soft robots, but they suffer from critical drawbacks since previously reported soft actuators often rely on electrical wires or pneumatic tubes for the power supply, which would limit the potential usage of soft robots in various practical applications. In this article, we review the new types of untethered soft actuators that represent breakthroughs and discuss the future perspective of soft actuators. We discuss the functional materials and innovative strategies that gave rise to untethered soft actuators and deliver our perspective on challenges and opportunities for future-generation soft actuators.Y