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Abstract: A scenario, a broad-brush description of a possible future evolution of a system, can be specified in terms of a set of FEPs (Features, Events and Processes) and their interactions. KAERI has developed a scenario using the PID (Process Influence Diagram) method to reveal the interactions between processes in detail. For the development of PID, KAERI established a methodology of four principles based on the KAERI RES (Rock Engineering System). According to the methodology, a model PID of a reference scenario is under development and three sub-PIDs of a container corrosion, a mechanical stress change and a radionuclide migration sub-scenario have been constructed. Also, a main frame for a full PID has been integrated using two sub-PIDs such as a container corrosion sub-scenario and a mechanical stress change sub-scenario. After constructing the full PID of a reference scenario, the other PIDs will be constructed in a similar manner to the model PID. In addition, various reduced PIDs as well as a full PID will be provided to meet a user''s requirements. Realization of the scenario using RES and PID is expected to increase the confidence and the transparency for a safety assessment of a high-radioactive waste repository. [Copyright &y& Elsevier]

Abstract: The innermost shelf of the eastern Korea Strait is a ria-type coastal sea comprising islands, intervening passageways and embayments. A detailed analysis of high-resolution (1−10 kHz) subbottom profiles and core sediments from this area reveals complicated depositional and distributional patterns of the Holocene mud deposits related to complex topography with varying supply of the adjacent Nakdong riverine sediments. Sediments from the Nakdong River were bifurcated around Gadeok Island, forming two proximal systems: Nakdong and western Gadeok systems. These proximal systems prograded offshore (southward) by active sediment supply from the Nakdong River in the early stage. Suspended sediments passing through the Nakdong system formed the distal (Gadeok Waterway and eastern Geoje) systems in the area between the northern Geoje and Gadeok islands. These distal systems show a northwestward (onshore) prograding tendency to Jinhae Bay, the biggest bay in the vicinity of the Nakdong estuary in which the Jinhae Bay system developed. In the late stage, a remarkable decrease of sediment supply from the Nakdong River has caused retrograding geometry of the two proximal systems. However, the most distal (Jinhae Bay) system has continuously prograded bayward due to the persistent supply of sediments resuspended by strong tidal currents from nearby distal (Gadeok Waterway and eastern Geoje) systems. These complex depositional features indicate that topography has an important influence on depositional developments of the Holocene mud deposits by controlling path and intensity of sediment dispersal and resuspension processes. [Copyright &y& Elsevier]

The Ulleung Interplain Gap (UIG) is a deep (2300–2700 m) passage which has served as a conduit for deep-water circulation between the Ulleung and Japan basins. A detailed analysis of Chirp (2–7 kHz) subbottom profiles (ca. 6270 line-km) and nine sediment cores (8.6–11.4 m long) together with age data of tephra layers and four AMS 14C from the UIG and the adjacent areas reveals complex sedimentation caused by an interaction between bottom currents and mass flows during the last- and post-glacial periods. From high-resolution subbottom data, rock basement, slide/slump/rock-fall deposits, mass-flow chutes/channels, mass-flow deposits, bottom-current deposits, and a large-scale bottom-current channel system are recognized. Core sediments consist of various deposits of turbidites, muddy contourites, manganiferous contourites, and pelagic/hemipelagic sediments. Based on vertical distribution of sedimentary facies together with a chronostratigraphic framework, core sediments can be divided into Units I (<∼15 ka) and II (>∼15 ka).The extensive mass-flow deposits with slope failures on the entire slopes of topographic highs around the UIG and the dominant turbidites in Unit II (>∼15 ka) suggest that a relatively large amount of sediment was delivered into the UIG by frequent mass flows (recurrence intervals of ca. 250–500 years in the upper Unit II) during the last-glacial period. Erosion or hampered sedimentation by bottom currents is indicated by the truncated reflectors of channel walls and muddy/manganiferous contourites in the Ulleung Interplain Channel (UIC) along the UIG. Interbedded turbidites in the UIC floor reflect that some large-scale mass flows intermittently entered into the UIC.The UIC has an asymmetric channel-flank geometry. The southeastern flank shows a gentle, wide mound morphology of mass-flow deposits derived from large-scale slope failures on the slopes of the Oki Bank, reflecting a dominance of downslope gravitational processes over alongslope bottom currents. In contrast, the northwestern flank is characterized by a narrow, steep geometry of mass-flow deposits, where a relatively small amount of sediment derived from the slopes of the South Korea Plateau could not overcome bottom-current activity.The dominant muddy and manganiferous contourites with rare turbidites in Unit I (<∼15 ka) reflect intensified bottom currents and infrequent slope failures (recurrence intervals of ca. 1700–5000 years) during the post-glacial period. These conditions facilitated the formation of a thin, elongate mound of bottom-current drifts overlying mass-flow deposits on the southeastern UIC flank, and sustained erosion or hampered sedimentation in the UIC. [Copyright &y& Elsevier]

The objective of this study was to examine the fate of foodborne pathogens (Bacillus cereus, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella Typhimurium, and Staphylococcus aureus) and B. cereus spores in Korean turbid rice wine (Makgeolli). Samples of sterilized and non-sterilized turbid rice wine were inoculated with each of the vegetative bacteria or B. cereus spores at 3–4 log CFU/ml. The samples were stored at 5 °C or 22 °C, and bacterial survival was monitored over 28 days. Despite the harsh environment (alcohol content: 6–7% and pH: 3.43–3.98), long-term survival of pathogens was observed. Survival time was different depending on the type of beverage (pathogens survived longer in sterilized wine than in non-sterilized wine), cellular state (spores survived longer than vegetative cells), species (B. cereus survived longer than other species), and storage temperature (pathogens survived longer at 5 °C then at 22 °C). The number of B. cereus spores remained constant at both temperatures. The vegetative B. cereus population declined rapidly within 1 day, but then remained steady for up to 28 days (1.20–1.55 log CFU/ml in sterile wine). These results indicate that B. cereus formed spores that survived for a long time; therefore, it is possible that B. cereus may exist as spores in turbid rice wine. E. coli O157:H7, L. monocytogenes, S. Typhimurium, and S. aureus survived for up to 28, 14, 14, and 14 days, respectively, in sterilized wine at 5 °C. Thus, the health implications of the long-term survival of pathogens in alcoholic beverages should be carefully considered. The results provide new information that may be useful in predicting the potential microbiological hazards associated with turbid rice wine. [ABSTRACT FROM AUTHOR]

Summary: Objectives: Mutations in the GJB2, GJB6 and SLC26A4 genes are a frequent cause of hearing loss in a number of populations. However, little is known about the genetic causes of hearing loss in the Korean population. Methods: We sequenced the GJB2 and GJB6 genes to examine the role of mutations in these genes in 22 hearing loss patients. We also sequenced the SLC26A4 gene in seven patients with inner ear malformations, including enlarged vestibular aqueduct (EVA) revealed by computer tomography. Results: Coding sequence mutations in GJB2 were identified in 13.6% of the patients screened. Two different mutations, 235delC and T86R were found in three unrelated patients. The 235delC was the most prevalent mutation with an allele frequency of 6.9% in our patient group. No mutations, including 342-kb deletion, were found in GJB6 gene. Three different variants of SLC26A4 were identified in the EVA patients, including one novel mutation. Four EVA patients carried two mutant alleles of SLC26A4, and at least one allele in all patients was the H723R mutation, which accounted for 75% of all mutant alleles. Conclusions: Our results suggest that GJB2 and SLC26A4 mutations together make up a major cause of congenital hearing loss in the Korean population. Further studies may be able to identify other common variants that account for a significant fraction of hearing loss in the Korean population. [Copyright &y& Elsevier]