Korea University

About: Korea University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 39756 authors who have published 82424 publications receiving 1860927 citations. The organization is also known as: Bosung College & Bosung Professional College.

Applications of proton exchange membrane fuel cell systems

Abstract: Proton exchange membrane fuel cells (PEMFCs) have recently passed the test or demonstration phase and have partially reached the commercialization stage due to the impressive worldwide research effort. Despite the currently promising achievements and the plausible prospects of PEMFCs, there are many challenges remaining that need to be overcome before PEMFCs can successfully and economically substitute for the various traditional energy systems. With the many promising research efforts in overcoming these challenges, the most important tools for the commercialization of PEMFCs will be the technical data and information from a real PEMFC application test. For these reasons, this paper introduces and discusses the remaining challenges and some of the latest research on the application test of PEMFC to real systems such as transportation, residential power generation and portable computers. In addition, this paper describes and summarizes the relative prospects and the competitive force of PEMFCs in these fields. These prospects primarily depend on stable and economical high-purity hydrogen supplies, the scale of application, the existence of more efficient competitive power sources and the social viewpoints such as the health and environment benefits as well as infrastructural aspects associated with traditional power supply and demand. The review shows that PEMFC have the most promising applications to buses, recreation vehicles, and lightweight vehicles. Without doubt, the technology for a stable supply of high-purity hydrogen along with the corresponding infrastructure is essential for the success of PEMFC in various application fields.

Overexpression of the Tobacco Tsi1 Gene Encoding an EREBP/AP2–Type Transcription Factor Enhances Resistance against Pathogen Attack and Osmotic Stress in Tobacco

Abstract: Using mRNA differential display analysis, we isolated a salt-induced transcript that showed a significant sequence homology with an EREBP/AP2 DNA binding motif from oilseed rape plants. With this cDNA fragment as a probe, cDNA clone Tsi1 (for Tobacco stress-induced gene1) was isolated from a tobacco cDNA library. RNA gel blot analysis indicated that transcripts homologous with Tsi1 were induced not only in NaCl-treated leaves but also in leaves treated with ethephon or salicylic acid. Transient expression analysis using a Tsi1::smGFP fusion gene in BY-2 cells indicated that the Tsi1 protein was targeted to the nucleus. Fusion protein of Tsi1 with GAL4 DNA binding domain strongly activated transcription in yeast, and the transactivating activity was localized to the 13 C-terminal amino acids of Tsi1. Electrophoretic mobility shift assays revealed that Tsi1 could bind specifically to the GCC and the DRE/CRT sequences, although the binding activity to the former was stronger than that to the latter. Furthermore, Agrobacterium-mediated transient expression and transgenic plants expressing Tsi1 demonstrated that overexpression of the Tsi1 gene induced expression of several pathogenesis-related genes under normal conditions, resulting in improved tolerance to salt and pathogens. These results suggest that Tsi1 might be involved as a positive trans-acting factor in two separate signal transduction pathways under abiotic and biotic stress.

Education and Income Inequality: New Evidence from Cross-Country Data

Abstract: This paper presents empirical evidence on how education is related to income distribution in a panel data set covering a broad range of countries for the period between 1960 and 1990. The findings indicate that educational factors - higher educational attainment and more equal distribution of education - play a significant role in making income distribution more equal. The results also confirm the Kuznets inverted-U curve for the relationship between income level and income inequality. We also find that government social expenditure contributes to more equal distribution of income. However, a significant proportion of cross-country variation in income inequality remains unexplained.