• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.131-138
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• 2009

Heavy metal residues in soil, rice straw, unhulled rice, rice hull, polished rice, and rice barn on the rice paddy in the "Top rice production complex which is non-contaminated area were evaluated. It was observed that the average concentrations of As, Cd, Cu, Pb, and Hg in the paddy soils were 1.235, 0.094, 4.412, 4.728 and 0.0279 mg/kg, respectively. There were no cultivation areas exceeded of the threshold for soil contamination designated by "The Soil Environment Conservation Law" in Korea. For the polished rice, there were no samples exceeded of a permissible level of heavy metal residues such as 0.051 mg/kg of As, 0.040 mg/kg of Cd, 0.345 mg/kg of Cu, 0.065 mg/kg of Pb and 0.0015 mg/kg of Hg. For the uptake and translocation of heavy metals to rice plant, a main part of heavy metal accumulation was rice straw, and then rice bran. Furthermore, it shown that accumulation of heavy metals in unhulled rice, rice hulls, brown rice, and polished rice was approximately similar as low. The slopes of translocation of heavy metals from soil to polished rice were following order as Cd, 0.4321 > Cu, 0.054 ${\fallingdotseq}$ Hg, 0.052 > As, 0.021 > Pb, 0.008. It was observed that potential ability of Cd uptake in rice plant and then its translocation into polished rice was very high. Concentrations of copper and mercury absorbed in the rice plant were moderate for translocating into the polished rice, while the arsenic and lead in the plant were scarcely translocated into the polished rice. The distribution of heavy metals absorbed and translocated into aboveground parts of rice plant was appeared that there were remained at 63.3-93.4% in rice straw, 6.6-36.9% in unhulled rice, 0.6-5.7% in rice hulls, 3.2-31.3% in brown rice, 0.8-4.6% in rice bran and 1.1-26.7% in polished rice. The accumulation ratio of Cd in the aboveground parts of rice plant was remained at 26.7-31.3% in brown and polished rice.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.2
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• pp.163-173
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• 2013

When the mandible performs opening movement, the condyle-disk complex conducts sliding movement along the articular eminence. Thus, anatomic configuration of articular eminence is very important to normal movement of TMJ. The purpose of this study was to measure the posterior slope of the articular eminence and evaluate the effect of a pathologic bone change in the condylar head on the stiffness of articular eminence, and compare the differences of the articular eminence slope by gender and age using dental cone-beam CT. As using i-CAT Cone-Beam Computed Tomography, the CT images of 204 TMJs of 102 patients(43 men and 59 women, mean age: 37.7 years) who were diagnosed at Wonkwang University Sanbon Dental Hospital were evaluated. All images were converted into a TMJ analysis mode to observe the continuous sagittal section images and coronal section images of the joints. To observe and assess bone changes in the condyle, three dentists measured the stiffness of the articular eminence on the same images, and when two of the three dentists agreed on their reading, these results were adopted and recorded. The articular eminence slope, considering the condylar anatomic configuration, was measured in three regions, namely, lateral part, central part, and medial part of the condyle. In the cases of a normal condyle(NCBC) and a condyle(CBC) with bone change, the articular eminence slopes were $57.0^{\circ}$(NCBC) and $51.8^{\circ}$(CBC) at the medial part, $57.9^{\circ}$(NCBC) and $52.4^{\circ}$(CBC) at the central part, and $55.1^{\circ}$(NCBC) and $49.5^{\circ}$(CBC) at the lateral part of the condyle. And the articular eminence slope of the condyle with bone change demonstrated less steepness than that of normal condyle (p<0.05). The articular eminence slope showed mediolaterally that it was the steepest at the central, followed by at the medial, and at the lateral (p<0.05). There were no significant differences by the gender and the age (p.0.05).

• Geophysics and Geophysical Exploration
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• v.23 no.1
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• pp.22-37
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• 2020

We analyze the comprehensive three-dimensional (3D) magnetic structure characteristics from the seafloor to the deep layer of the Tofua Arc (TA) 12 seamount in the Tonga Arc, Southwestern Pacific, using bathymetric and geomagnetic data, and magnetization vector inversion (MVI) results. The seafloor features surrounding TA 12 highlight a NW-SE-oriented elliptical caldera at the summit of the seamount, two small cones in the depressed area. A large-scale sea valley is present on the western flank of the seamount, extending from these caldera cones to the southwestern base of the seamount. TA 12 seamount exhibits a low magnetic anomaly in the caldera depression, whereas a high magnetic anomaly is observed surrounding the low magnetic anomaly across the caldera summit. It is therefore presumed that there may be a strong magnetic material distribution or magma intrusion in the caldera. The 3D MVI results show that the high anomaly zones are mainly present in the surrounding slopes of the seamount from the seafloor to the -3,000 m (below the seafloor) level, with the magnetic susceptibility intensity increasing as the seafloor level increases at the caldera depression. However, small high anomaly zones are present across the study area near the seafloor level. Therefore, we expect that the magma ascent in TA 12 seamount migrated from the flanks to the depression area. Furthermore, we assume that the complex magnetic distribution near the seafloor is due to the remnant magnetization.