We investigated physicochemical properties and isotopic compositions of organic matter (δ13CTOC and δ15NTN) in the old fish farming (OFF) site after the cessation of aquaculture farming. Based on this approach, our objective is to determine the organic matter origin and their relative contributions preserved at sediments of fish farming. Temporal and spatial distribution of particulate and sinking organic matter (OFF sites: 2.0 to 3.3 mg L-1 for particulate matter concentration, 18.8 to 246.6 g m-2 day-1 for sinking organic matter rate, control sites: 2.0 to 3.5 mg L-1 for particulate matter concentration, 25.5 to 129.4 g m-2 day-1 for sinking organic matter rate) between both sites showed significant difference along seasonal precipitations. In contrast to variations of δ13CTOC and δ15NTN values at water columns, these isotopic compositions (OFF sites: -21.5‰ to - 20.4‰ for δ13CTOC, 6.0‰ to 7.6‰ for δ15NTN, control sites: - 21.6‰ to - 21.0‰ for δ13CTOC, 6.6‰ to 8.0‰ for δ15NTN) investigated at sediments have distinctive isotopic patterns (p<0.05) for seawater-derived nitrogen sources, indicating the increased input of aquaculture-derived sources (e.g., fish fecal). With respect to past fish farming activities, representative sources (e.g., fish fecal and algae) between both sites showed significant difference (p<0.05), confirming predominant contribution (55.9±4.6%) of fish fecal within OFF sites. Thus, our results may determine specific controlling factor for sustainable use of fish farming sites by estimating the discriminative contributions of organic matter between both sites.

One of the most demanded competencies of an oral health professional such as an oral pathologist is the ability to make clinical decisions. The purpose of this study was to examine the neurological differences between beginners and experts in the clinical decision-making process which consisting of complex, dynamic and sophisticated cognitive processes, and to identify the characteristics of experts based on the brain by comparing EEG activity. This study conducted experimental design with 10 dentists with more than 10 years of clinical experience and 10 students with short clinical experience as beginners as a fourth year student before graduation. The hypothesis-oriented algorithm proposed in HOAC II was used. As a standard, the clinical decision-making stage of the dentist was divided into three stages, and an event was developed and an experiment was designed for measuring EEG for each stage. The cerebral activity distribution patterns of the two groups were measured with EEG, compared and analyzed with pre-processing process using EEGlab. As a result, the difference in the auditory information was not noticeable between the novice and the expert, but the difference between the group of the novice and the expert appeared in the visual data and the radiographic data. In the case of beginners, the activity was higher in the left hemisphere, and in the case of experts, both brains were activated. The results of this study are intended to present objective information based on brain-based analysis of differences that appear in the clinical decision-making process of experts and beginners. It can be used as basic research data to present the brain-based characteristic analysis of dentist experts.

In this study, we prepare pure WO3 inverse opal(IO) film with a thickness of approximately 3 μm by electrodeposition, and an ultra-thin TiO2 layer having a thickness of 2 nm is deposited on WO3 IO film by atomic layer deposition. Both sets of photoelectrochemical properties are evaluated after developing dye-sensitized solar cells(DSSCs). In addition, morphological, crystalline and optical properties of the developed films are evaluated through field-emission scanning electron microscopy(FE-SEM), High-resolution transmission electron microscopy(HR-TEM), X-ray diffraction(XRD) and UV/ visible/infrared spectrophotometry. In particular, pure WO3 IO based DSSCs show low VOC, JSC and fill factor of 0.25 V, 0.89 mA/cm2 and 18.9 %, achieving an efficiency of 0.04 %, whereas the TiO2/WO3 IO based DSSCs exhibit VOC, JSC and fill factor of 0.57 V, 1.18 mA/cm2 and 50.1 %, revealing an overall conversion efficiency of 0.34 %, probably attributable to the high dye adsorption and suppressed charge recombination reaction.

This study investigated the surface pit corrosion of SS420J2 stainless steel accompanied by intergranular crack. To reveal the causes of surface pits and cracks, OM, SEM, and TEM analyses of the microstructures of the utilized SS420J2 were performed, as was simulated heat treatment. The intergranular cracks were found to have been induced by a grain boundary carbide of (Cr,Fe)23C6, which was identified by SEM/EDS and TEM diffraction analyses. The mechanism of grain boundary sensitization occurred at the position of the carbide, followed by its occurrence at the Cr depleted zone. The grain boundary carbide of (Cr,Fe)23C6 type precipitated during air cooling condition after a 1038 °C solid solution treatment. The carbide precipitate formation also accelerated at the band structure formed by cold working. Therefore, using manufacturing processes of cooling and cold working, it is difficult to protect SS420J2 stainless steel against surface pit corrosion. Several counter plans to fight pit corrosion by sensitization were suggested, involving alloying and manufacturing processes.