• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.3
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• pp.271-279
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• 2008

Polymetallic sulphides means hydrothermally formed deposits of sulphide minerals which contain concentrations of metals including, inter alia, copper, lead, zinc, gold and silver. Nautilus is the first company to commercially explore the seafloor polymetallic sulphide deposits. The Company holds exploration licences and exploration applications for more than 370,000 $km^2$ in the jurisdictional seas of Papua New Guinea, Fiji, Tonga, the Solomon Islands and New Zealand along the western Pacific Ocean's Rim of Fire. Neptune Minerals is also a leading explorer and developer in this field, with exploration licences awarded totalling more than 270,000 $km^2$ in the territorial seas or EEZ of New Zealand, Papua New Guinea and the Federated States of Micronesia. These two companies now carry out the most active investment activities for seafloor polymetallic sulphide deposits with a goal of commercial production by 2010. China and Japan carry out exploration activities for the seafloor polymetallic sulphide deposits to secure supplies of strategic metals. China carries out national R&D projects relating to deep sea mineral resources in the world ocean through China Ocean Mineral Resources R&D Association(COMRA). And Japan investigates her own EEZ for exploration of the seafloor polymetallic sulphide deposits. In consideration of aforementioned international activities of coastal nations as well as private companies for exploring the sulphide deposits, Korea shall prepare strategic plans : First, consolidation of the authorities concerned and legislative support; second, determination of main entity of the project; third, securing government's decisive investment of sufficient budget; and lastly, establishment of the mid, long-term plan for development of seafloor polymetallic sulphides deposits.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.2
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• pp.140-146
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• 2008

Marine ecotoxicological standard method using fish larvae was established with the standard test species of Oryzias latipes(Japanese Medaka) and Paralichthys olivaceus(flounder) and with the 7 day $LC_{50}$ as endpoint. Test method referred to the USEPA(1994) with the replacement of test species found in the Korean water. Standard test species were selected in terms of the species supply and ecological importance in Korean waters. Japanese medaka can be reared with small tanks in the lab and has wide tolerance on salinity, and flounder eggs can be easily obtained from commercial fish hatcheries. General conditions for larval fish toxicity test are as follows. The possible salinity ranges for toxicity test were $0{\sim}35\;psu$ for medaka and >20 psu for flounder. Test type was designated as static non-renewal test if the dissolved oxygen in the test chamber does not fall below 4.0 mg/L. Ages of test species were selected as 7 days after hatched for medaka(about 5 mm TL) and 25 days for flounder(about 10 mm TL) because of the low natural mortality after these periods. Test can be accepted when the survival rates are over 80% in control. Also, species sensitivity on standard reference materials(copper, cadmium or zinc) must be provided with the toxicity test results.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.544-551
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• 2013

The effect of different silicon (Si) sources and methods of application on the growth of two chrysanthemum cultivars grown in a soilless substrate was investigated. Rooted terminal cuttings of Dendranthema grandiflorum 'Lemmon Eye' and 'Pink Eye' were transplanted into pots containing a coir-based substrate. A nutrient solution containing 0 or $50mg{\cdot}L^{-1}$ Si from calcium silicate ($CaSiO_3$), potassium silicate ($K_2SiO_3$) or sodium silicate ($Na_2SiO_3$) was supplied once a day through an ebb-and-flood sub irrigation system. A foliar spray of 0 or $50mg{\cdot}L^{-1}$ Si was applied twice a week. Cultivar and application method had a significant effect on plant height. Cultivar, application method, and Si source had a significant effect on plant width. Of the three Si sources studied, $K_2SiO_3$ was found to be the best for the increasing number of flowers, followed by $CaSiO_3$ and $Na_2SiO_3$. In both the cultivars, sub irrigational supply of Si developed necrotic lesions in the older leaves at the beginning of the flowering stage as compared to the control and foliar spray of Si. Cultivar, application method, Si source, and their interactions had significant influence on leaf tissue concentrations of calcium (Ca), potassium (K), phosphorus (P), magnesium (Mg), sulfur (S), sodium (Na), boron (B), iron (Fe), and zinc (Zn). The addition of Si to the nutrient solution decreased leaf tissue concentrations of Ca, Mg, S, Na, B, Cu, Fe, and Mn in both cultivars. The greatest Si concentration in leaf tissue was found in 'Lemmon Eye' ($1420{\mu}g{\cdot}g^{-1}$) and 'Pink Eye' ($1683{\mu}g{\cdot}g^{-1}$) when $K_2SiO_3$ was applied through a sub irrigation system and by foliar spray, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.240-244
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• 2013

We investigated the nutritive value and ruminal in situ dry matter degradability of whole crop rice silage prepared using Chucheongbyeo (WCRS) as a roughage source for ruminants. The crude protein (7.54%), acid detergent fiber (29.63%), neutral detergent fiber (62.98%), and total digestible nutrient (TDN) (57.88%) found higher in WCRS than those of rice straw. Manganese content in the WCRS was the highest, followed by carbon, iron, zinc, and copper, but magnesium content was the lowest. Glutamic acid content in WCRS was the highest, followed by leucine, asparagine, alanine, valine, arginine, and methionine content was the lowest. We examined ruminal in situ digestibility from total whole crop rice (TWCR), rice husks containing rice (RHR), whole crop rice except RHR (WER), and husked grain (HG) for 3, 6, 12, 24, and 48 hours. Ruminal in situ digestibility in the HG was the highest, followed by RHR, TWCR, and WER. Therefore, we suggest that ruminal in situ degradability was influenced by parts of whole crop rice, and the content of manganese and glutamic acid were the highest in WCRS.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.659-667
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• 2009

Casein is considered to be the main source of protein in milk; therefore, many studies have been conducted to identify casein-derived bioactive peptides and their physiological effects. Casein is inactive within the parent protein but can be liberated by various proteases and enzymatic hydrolysis during microbial fermentation and gastrointestinal digestion. Once absorbed, casein exhibits different bioavailabilities in the body. Specifically, casein-derived peptides function as angiotensin converting enzyme (ACE) inhibitor in the cardiovascular system; thus, they are expected to reduce and prevent hypertension. Additionally, casein-derived peptides behave as opioid-like peptides in the nervous system, which impacts relaxation. These peptides are also expected to modulate various aspects of immune functions. Finally, caseinophosphopeptide (CPP) and glycomacropeptide (GMP) may exhibit a number of nutritional effects such as the absorption of calcium, iron or zinc. Many studies have been conducted to evaluate casein-derived peptides due to their multifunctional properties and the results of these studies have contributed to the development of a wide variety of functional dairy products. The purpose of this paper was to review the generation of bioactive peptides, their absorption and metabolism, and their specific bioactive effects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.459-463
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• 2017

Hot dip galvanizing in the steel plant is one of the most widely used methods for preventing the corrosion of steel materials including structures, steel sheets, and materials for industrial facilities. While hot dip galvanizing has the advantage of stability and economic feasibility, it has difficulty in repairing equipment and maintaining the facilities due to high-temperature oxidation caused by Zn Fume where molten zinc used in the open spaces. Currently, SM45C (carbon steel plate for mechanical structure, KS standard) is used for the equipment. If a part of the equipment is resistant to high temperature and Zn fume, it is expected to improve equipment life and performance. In this study, the manufactured Ni alloy was tested for its corrosion resistance against Zn fume when it was used in the hot dip galvanizing equipment in the steel plant. Two kinds of materials currently used in the equipment, new Ni alloy and Inconel(typical corrosion-resistant Ni alloy), were selected as the reference groups. Two kinds of molten metal were used to confirm the corrosion of each alloy according to the molten metal. Zn fume was generated by bubbling Ar gas from molten Zn in a furnace($500{\sim}700^{\circ}C$) and the samples were analyzed after 30 days. After 30 days, the specimens were taken out, the oxide layer on the surface was confirmed with an optical microscope and SEM, and the corrosion was confirmed using a potentiodynamic polarization test. Corrosion depends on the type of molten metal.

• Journal of Nutrition and Health
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• v.26 no.6
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• pp.772-782
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• 1993

This study was conducted to assess the relationships between maternal dietary intakes and milk contents of minerals and trace elements, and the correlation among levels of these milk constituents. Maternal dietary intakes were measured and milk samples were collected at 2∼5 days, 2, 4, 6 and 12 weeks postpartum from 29 lactating women. The results obtained are sumarized as follows: 1) The overall mean nutrient intakes of lactating women in this study were below the recommended allowances and there were extensive individual variations between subjects. 2) Concentrations of minerals and trace elements in matured human milk showed the same range reported from different countries with the exception of calcium, magnesium, manganese and molybdenum which were relatively high. 3) There were no significant relationships between maternal dietary intakes of minerals and the corresponding mineral levels of human milk. In addition, no significant correlations were found between maternal vitamin C intake and the iron contents of milk. These were significant positive correlations between maternal calcium intake and the magnesium level of milk ; between maternal protein intake and the contents of zinc and copper in human milk. Maternal energy intake was negatively correlated with milk sodium level. 4) Pearson correlation coefficient showed positive significant relationships between levels of 17 pairs of various mineral and trace elements : sodium and potassium, iron ; potassium and calcium, phosphors, magnesium, iron, copper, manganese ; calcium and magnesium, iron manganese, molybdenm, nickel ; magnesium and iron, molybdenum ; iron and copper ; nickel and manganese.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.533-543
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• 2005

The purpose of this study was to determine the iron status of preschool children in Ulsan, Korea. The study was con-ducted using 95 children aged 3 to 6 years by investigating the anthropometric indices and assessing the dietary intakes and biochemical analysis. A questionnaire for dietary intakes using 24-hr recall method were carried out by the mothers of the 95 subjects. And also a study was conducted to assess hematological and biochemical status of iron and prevalence of iron deficiency. The average height and weight were 105.4 $\pm$ 7.0 cm, 18.7 $\pm$ 3.2 kg in boys, 103.8 $\pm$ 6.7 cm, 17.6 $\pm$ 2.7 kg in girls. These were lower than the body growth standard values of Korean pediatrics. There was not a significant difference in both between boys and girls. For the daily nutrient intake, energy was 1201.5 $\pm$ 280.9 kcal (79.3$\%$RDA), protein was 63.8 $\pm$ 28.2 g (219.4$\%$RDA), iron was 11.9 $\pm$ 4.5 mg (133.2$\%$RDA). The iron nutritional status by hematological assay found that Hct was 34.7 $\pm$ 2.0 ($\%$), Hb was 12.0 $\pm$ 0.8 g/dl, RBC was 4.3 $\pm$ 0.3 ($10^6/{\mu}l$), MCV was 80.5 $\pm$ 3.0 fL, MCH was 27.8 $\pm$ 1.1 pg and MCHC was 34.6 $\pm$ 0.6 g/dl. The biochemical measurement of serum iron was 75.6 $\pm$ 30.3 ${\mu}g$/dl, TIBC was 320.3 $\pm$ 34.1 ${\mu}g$/dl, serum ferritin was 30.0 $\pm$ 14.8 ${\mu}g$/dl, Zinc-Protophor-phyrin (ZPP) was 32.7 $\pm$ 8.0 ${\mu}g$/dl, and ZPP/Heme was 71.1 $\pm$ 19.5 ($\mu$mole/mol heme). The prevalence with Hct, Hb, TS and serum ferritin less than cut-off value was $8.4\%,\;9.5\%,\;12.6\%$ and $4.4\%$ respectively. But the prevalence of iron deficiency estimated with ZPP and ZPP/Heme criteria were $25.3\%$ and $27.4\%$, and were higher than in case of any other indices. The prevalence of iron deficiency anemia ((low Hb (< 11.0 g/dl) and low serum ferritin (< 10 ${\mu}g$/L) or low TS (3-4 yews: < $12\%$, 5-6 years: < $14\%$)) was found in only one 3 year old girl. The prevalence of iron deficiency except Hct and Hb was the highest in 3 year group, but the prevalence by Hct and Hb was the highest in 5 year group. Iron deficiency and iron deficiency anemia do not seem to be a major public health problem in preschool children in Ulsan.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.570-577
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• 2005

The purpose of this study was to investigate the effect of bone mineral density on life styles, dietary habits and nutrient intakes among the male college students. The subjects were divided into four groups; $Q_1$ (calcaneus BMD < 25 percentile, n = 117), $Q_2$ (25 percentile $\le$ calcaneus BMD < 50 percentile, n = 118), $Q_3$ (50 percentile $\le$ calcaneus BMD < 75 percentile, n = 118) $Q_4$ (calcaneus BMD $\ge$ 75 percentile, n = 116). And they were asked about general characteristics, life style, dietary habit, and nutrient intake using questionnaire and 24-hr recall method. They were measured the bone mineral density of calcaneus using quantitative ultrasound. The average age of the subjects of the study was 23.0 yews and the average height, weight, and BMI were 174.7 cm, 69.0 kg, $22.5 kg/m^2$. The bone mineral density in calcaneus was $0.43 g/cm^2$ in $Q_1,\;0.50 g/cm^2$ in $Q_2,\;0.56 g/cm^2$ in $Q_3$, and $0.69 g/cm^2$ in $Q_4$ (p < 0.001). The results showed that $Q_1$ tended to have irregular exercise compared to the other three groups. Compared with $Q_1$ and $Q_2$, the frequency of skipping breakfast was lower in $Q_3$ and $Q_4$. Also the results showed that the $Q_4$ was significantly more often to drink coffee compared with the other three groups (p < 0.01). The mean daily energy intake was 2210.6 kcal ($88.4\%$ of RDA). The intake of energy, vitamin $B_2$, calcium, and zinc did not meet the Korean RDA. Also the $Q_2$consumed significantly lower intakes of protein (p < 0.05) and plant protein (p < 0.05) compared to the $Q_3$ and $Q_4$. The $Q_1$ and $Q_2$ consumed significantly lower intakes of vitamin $B_2$ (p < 0.01) compared to the $Q_3$ and $Q_4$. In conclusion, male student in lower bone mineral density appeared to have unhealthy life styles and dietary habits in terms of irregular exercise, high frequency of skipping breakfast and lower intakes of protein, vitamin $B_2$ showing a strong need proper education on meal practices and exercise habits for the bone health.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.544-552
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• 2005

This study was conducted to examine the correlation among bone mineral density (BMD), hair and nail calcium and magnesium contents, and nutrient intakes in preschool children in Chungnam district. A total of 111 preschool children (61 boys, 50 girls) measured the anthropometric characteristics, the bone mineral density of carpus using DEXA and hair and nail calcium and magnesium contents were analyzed by ICP spectrometer. The average ages of the study subjects were 55.7 months in boys and 53.0 months in girls (3.8${\~}$7 years). The birth height and weight of subjects were 51.0 cm and 3.3 kg in boys and 50.3cm and 3.2kg in girls, respectively. The average height, weight, $\%$ body fat, and obesity index were 111.6 cm, 19.6 kg, $15.0\%,\;96.1\%$ in boys and 108.6 cm, 18.5 kg, $17.5\%,\;98.1\%$ in girls, respectively. The bone mineral density in carpus was $0.25 g/cm^2$ in boys and $0.24 g/cm^2$ in girls. The hair calcium and magnesium contents were 440.9 ppm, 16.4 ppm in boys and 373.2 ppm, 28.9 ppm in girls. The nail calcium and magnesium contents were 9.4 ppm, 2.1 ppm in boys and 10.4 ppm, 2.4 ppm in girls. The intakes of energy, calcium, iron, zinc, vitamin A. niacin, and vitamin C did not meet the Korean RDAs. The ultradis and average carpus BMD were positively correlated to the plant calcium intake (p < 0.05, p < 0.05). And the ultradis, distal, and average carpus BMD were positively correlated to the plant iron intake (p < 0.05, p < 0.05, p < 0.05). The average bone mineral density in the carpus was positively correlated to the nail magnesium content (p < 0.05). Therefore, more systematic studies to investigate the roles of iron and calcium intakes, nail magnesium content in bone development of preschool children were required.