• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.291-298
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• 2001

Seawater, sediment and biota in the Kwangyang Bay were analyzed by gas chromatography/quartz furnace atomic absorption spectroscopy (GC-QFAAS) to investigate concentrations and distribution pattern of butyltin compounds (TBT, DBT, MBT) during February, April and July, 1996, Marine biota analyzed were Tapes japcnicus and Crassostrea gigas. The concentrations of tributyltin (TBT) in seawater were in the range of ND-15.7 ng/L for the surface and ND-68.5 ng/L for the bottom. The highest concentration of TBT in seawater was detected in April for the both, surface and bottom water. The maximum value of $TBT_{(bottom)}/TBT_{(surface)}$, 3.6 in April showed the increased input of TBT from the surface water in April compared to February (2.1) and July (0.9). The concentrations of TBT in the sediment were in the range of ND-8.5 ng/g dry wt. The highest concentration of TBT in the sediment was measured in July, This result seems to attributed to the removal of TBT from water column via sorption onto particulate matters to the relatively undisturbed underlying sediment and increased input of TBT by increased fluxes of detritus of marine plankton after spring bloom, in July. The mean values of partitioning coefficient ($K_d$) of TBT between seawater and sediment were $3.0\times10^3$(February), $7.4\times10^3$(April) and $9.4\times10^3$(July). The concentrations of TBT in biosamples were in the range of ND-93.30 ng/g dru wt. (T. japonicus) and ND-138.53 ng/g dry wt. (C. gigas). The seasonal variation of TBT contents in biota was remarkable. The $K_d$ (biological concentration factor) was $7-41\times10^3$ for T. japonicus. and $5-34\times10^3$ for C. gigas. The measured TBT concentrations in seawater in the study area was sufficient to cause the imposex of shellfish and to retard the growth of aquatic organisms including oyster upon chronic exposure.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.116-121
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• 1989

An experiment on movements of copper in soils was conducted to evaluate the effectiveness of several soil extractants in predicting to be possibly the plant availability of copper in soils. Soil samples were taken six, from Las Virgines loam that the samples naturally included high contents of heavy metals near Los Angeles, Greenfield sandy loam and IDomino Loam that received 22.5, and $45.0mg.\;ha^{-1},\;yr^{-1}$ of composted sludge from Los Angeles from 1975 to 1983, respectively. Copper in soils were extracted with $4M\;HNO_3$, 0.1M HCl, 0.5M DTPA-0.1M TEA, 0.5M EDTA-0.1M $Ca(NO_3)_2$, and 1M ammonium acetate(pH 7), and analyzed by atomic absorption spectroscopy. The results were as follows: 1. The total copper contents in soil that received $45.0mg.\;ha^{-1},\;yr^{-1}$ of composted sludge were higher than that received $22.5mg.\;ha^{-1}.yr^{-1}$, regardless of soil samples. 2. The ratios of extractable copper contents with EDTA, DTPA, 0.1M HCl and 1M ammonium acetate to total copper contents extracted with 4M $HNO_3$ of long-term sludge applications were larger than those of natural, sludge-nontreated soils. 3. Statistically significant increase in total copper contents was found in the increasing values of multipling CEC, or OM% by R, ratio of extractable copper contents to those by 4M $HNO_3$ extraction as total copper contents in soils.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.189-195
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• 2015

To determine the contents of sodium (Na) and potassium (K) for restaurant dishes, 194 cases classified 26 kinds of restaurant dishes were collected from restaurants in Seoul and were analysed using the atomic absorption spectroscopy. Average contents of Na and K in Kimchi among restaurant dishes were highest as $554.9{\pm}155.5mg/100g$, $225.1{\pm}69.1mg/100g$, while average contents of Na and K were lowest in Seolleongtang as $24.2{\pm}5.8mg/100g$, $12.7{\pm}3.9mg/100g$ respectively. The contents between Na and K in restaurant dishes had a strong correlation of positive linear judging from 0.782 (p-value < 0.01) of the correlation coefficient. The Na/K ratio of Bulgogi was appropriate as $1.17{\pm}0.44$, while those of Udon, banquet noodles, Kalguksu were very high as shown more than 10. The contents of Na and K were examined 5 dish groups as Gook/Tang, Jjigae/Jeongol, stir-fried dish, noodle and Kimchi. Average contents of Na and K classified by dish groups were significantly difference (p-value < 0.001). Average content of Na among dish groups was highest in Kimchi as $554.9{\pm}155.5mg/100g$ followed by Jjigae/Jeongol, Gook/Tang, stir-fried dish and noodle. Similar to Na content, average content of K was highest in Kimchi as $225.1{\pm}69.1mg/100g$ followed by stir-fried dish, Jjigae/Jeongol, Gook/Tang and noodle. The ratio of Na/K by classified groups of dishes was shown as significantly difference (p-value < 0.001). Stir-fried dish was $1.18{\pm}0.44$ close to 1 followed by Kimchi, Jjigae/Jeongol, Gook/Tang, and noodle.

• Journal of Chest Surgery
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• v.42 no.6
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• pp.685-695
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• 2009

Background: Calcification is the most frequent cause of clinical failure of bioprosthetic tissues that are fabricated from Glutaraldehyde (GA)-fixed porcine valve or bovine pericardium. We recently used a multi-factorial approach of employing different mechanisms to investigate how to reduce the calcification of bioprosthetic tissues. The purpose of the present study was to evaluate the synchronized synergism using ethanol, L-lysine and $NaBH_4$ in glutaraldehyde treated porcine pericardium from the standpoint of calcification and tissue elasticity. Material and Method: Porcine pericardium was fixed with 0.625% GA (commercial fixation). An interim step of ethanol (80%; 1 day at room temperature) or L-lysine (0.1 M; 2 days at $37^{\circ}C$) or $NaBH_4$ (0.1 M; 2 days at room temperature) was followed by completion of the GA fixation (2 days at $4^{\circ}C$ and 7 days at room temperature). The tensile strength and thickness of the samples were measured. The treated pericardiums were implanted subcutaneously into three-week old Sprague-Dawley rats for 8 weeks. The calcium content was assessed by atomic absorption spectroscopy and the histology of the samples. Result: The amount of calcium in the pericardium pretreated with ethanol (13.6${\pm}$10.0 ug/mg, p=0.008), L-lysine (15.3${\pm}$1.0 ug/mg, p=0.002) and both (16.1${\pm}$11.1 ug/mg, p=0.012) was significantly reduced compared with the control (51.2${\pm}$8.5 ug/mg). However, $NaBH_4$ pretreatment (65.7${\pm}$61.8 ug/mg, p=0.653) and combined pretreatment that including ethanol, L-lysine and $NaBH_4$ (92.9${\pm}$58.3 ug/mg, p=0.288) were not significantly different from the controls(51.2${\pm}$8.5 ug/mg). Both the combined pretreatment using ethanol and L-lysine (7.60${\pm}$1.55, p=0.76) and the combined pretreatment that included ethanol, L-lysine and $NaBH_4$ (7.47${\pm}$1.85, p=0.33) increased the tensile strength/thickness ratio compared with that of the controls (4.75${\pm}$1.88). Conclusion: The combined pretreatment using ethanol and L-lysine seemed to decrease the calcification of porcine pericardium fixed with glutaraldehyde, as compared to single pretreatment, and it increase the tissue elasticity, but to the degree that showed synchronized synergism. $NaBH_4$ pretreatment seemed to increase the calcification of porcine pericardium, irrespective of whether single or combined pretreatment was used.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1303-1317
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• 2013

The purpose of this study was to determine the sodium (Na) and potassium (K) content of school meals served in elementary and junior high school in Korea. In this study, 872 kinds of school meal dishes were collected from twelve elementary and twelve junior high schools located in four different cities in Korea (Daegu, Masan, Gwangju, and Jeju). The dishes were classified into three main categories; staple dish, subsidiary dish, and dessert. Each main category was further sub-classified into 4 kinds of staple dishes, 15 kinds of subsidiary dishes, and 5 kinds of dessert dishes. The Na and K content of dishes were then analyzed by atomic absorption spectroscopy. The Na content of individual dishes showed considerable differences, ranging from 9 to 2,717 mg/100 g. Among the staple dishes, cooked rice contained relatively less Na, but other staple dishes such as a la carte, noodle, and rice-gruel contained considerably high amounts of Na. Regarding the subsidiary dishes, the Na content of salad was low, but those of Jangachi, stir-fried dishes, and kimchi were considerably high. Among the dessert dishes, beverages, fruit, and milk/dairy products contained relatively low amount of Na, while rice cakes and baked goods, and snacks contained noticeably high amounts of Na. Unlike the Na content, the K content between the dishes did not show much variability. Cooked rice and rice cakes contained relatively low amounts of K, similar to other dishes, and ranged from 104 to 220 mg/100 g. The Na/K ratio was especially high in rice cakes and Jangachi, while of the ratio in beverages, milk/dairy products, salad, and fruit were pretty low. The total content of Na and K and the Na/K ratio of elementary school meals were 974 mg, 378 mg and 2.7, respectively, and those in junior high school meals was 1,466 mg, 528 mg and 3.0. The results show that most school meals provide a significant amount of Na but significantly small amounts of K, as suggested by the Dietary Reference Intakes for Koreans.