• Journal of Environmental Health Sciences
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• v.36 no.3
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• pp.199-207
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• 2010

In this study, breast milk levels of indicator polychlorinated biphenyls (PCBs) were estimated, and statistics drawn, for 22 Koreans in the general population, aged 26-38, who had resided in metropolitan areas for more than 5 years without occupational exposure to organochlorine pollutants. Concentrations of indicator PCBs were measured using the isotope dilution method with a high resolution gas chromatograph/high resolution mass detector, which provided accurate and precise data for investigation of trends, and international comparisons. The geometric mean of total indicator PCB levels was 22.3 ng/g lipid, which is significantly lower than the level in individuals from European countries. Overall, the geometric mean and 95th percentile of the most abundant congener PCB 153 were 8.04 ng/g lipid and 16.4 ng/g lipid, respectively. PCB congeners 138, 153 and 180 together accounted for about 75% of the indicator congeners analyzed. Breast milk total indicator PCB concentrations were significantly associated with age and parity, but not with body mass index (BMI), rate of body weight increase, or smoking habits. The geometric mean level of PCB 153 in breast milk from mothers with a pre-pregnant BMI < $21\;kg/m^2$ was significantly higher than in pre-pregnant women with a BMI of ${\geqslant}\;21\;kg/m^2$ (p<0.05). Women who ate more fish, meat, and milk products did not have significantly higher total indicator PCB levels than those who ate less of these products, but a significant difference in PCB 153 levels was demonstrated between the subjects consuming higher (11.45 ng/g lipid) and lower (6.79 ng/g lipid) amounts of fish (p<0.05), after adjusting for confounders. These results suggest that age, parity and fish intake are the important factors affecting the concentrations of indicator PCBs in these subjects.

• Korean Journal of Environment and Ecology
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• v.30 no.5
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• pp.865-873
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• 2016

Since 2004, Asiatic Black Bear of the Jirisan National Park is subjected to the restoration project through the re-introduction by the Maritime Province of Siberia in Russia, North Korea, Northeastern part of China and Seoul Grand Park. The purpose of this study is to analyze diets with scat to identify Asiatic Black Bear's feeding habit and eating resources environment in the Jirisan National Park. 78 scats of Asiatic Black Bears were observed during the field studies of radio telemetry-marked bears and by chance in the Jrisan National Park, from 2005 to 2013. The relative frequency of occurrence demonstrated that the plants comprised the highest with 77%, followed by insects with 12.8%, mammals with 5.6%, birds with 0.5%, arthropoda with 0.5%, and others with 3.6%. Also, 52 scats among the collected scats that were measured for the ratio of food were subjected to dry weight, and plants were the highest with 91.2%, followed by mammals with 3.6%, insects with 1.0% and others with 4.2% in the order mentioned. Asiatic Black Bear's feed research demonstrated that the Asiatic Black Bear at Jirisan is omnivorous and that the vegetable food is the main feed instead of animal feed.

• Journal of the Korean Wood Science and Technology
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• v.40 no.1
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• pp.10-18
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• 2012

A high airtightness is required for the residential spaces constructed recently to save cooling and heating energy through improving insulation performance. Because the chances to release steam formed by human activity in building and inflow of water vapor in outdoor air to residential space are reduced, the natural humidity control performance of interior materials has become more important. In this study, hygroscopic performance of thermo-physically treated wood (Pinus koraiensis) was estimated. At various relative humidity condition, the water vapor adsorption and desorption rates of wooden materials were measured as well as equilibrium moisture content. Effects of roughness and surface microstructure as physical factors and functional groups as chemical factors on the hygroscopicity were analyzed. It is expected that the results from this study and further study of measuring moisture generation in residential spaces could contribute to install a system for evaluating the hygrothermal performance of wooden building.

• Korean Journal of Breeding Science
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• v.40 no.1
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• pp.63-67
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• 2008

A new peanut cultivar "Jopyeong" (Arachis hypogaea ssp. hypogaea L.) was developed at the Yeongnam Agricultural Research Institute, NICS, in Milyang in 2006. It was developed from the cross between the very short stem cultivar "CUP brittle" and the high-yielding cultivar "Daekwang". "Jopyeong" which is Virginia plant type has 23 branch number per plant with early maturing and ellipse-shaped large kernel. Each pod has two grains with brown testa and 100 seed weight was 87g in the regional yield trials (RYT). This variety also showed more resistant to late leaf spots compared with check one. Especially it has resistance to lodging owing to short stem and erect plant type. In the regional yield trials "Jopyeong" was out-yielded than check variety by 11% with 8.37 ton/ha for fresh pod and by 4% with 3.95 ton/ha for grain.