• Journal of environmental and Sanitary engineering
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• v.3 no.1 s.4
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• pp.69-74
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• 1988

This study was carried out to investigate water quality and pollution in the mineral water located in Seoul area. 15 sites were pointed out by random sampling and tested monthly for 14 items from July to December in 1986. 1. 14 sites were suitable for the drinking water standards but 1 site was not suitable for its pH (5.4). 2. The range of mineral element and concentration were as follows: $$K\;(1.1\pm0.19\~2.38\pm0.45ppm)$$ $$Na\;(5.14\pm0.32\~11.2\pm0.58ppm)$$ $$Ca\;(4.36\pm0.53\~14.44\pm0.53ppm)$$ $$Mg(1.58\pm0.32\~6.34\pm0.77ppm)$$ 3. Among the heavy metals, Fe, Zn, Mn, Cu, were detected small amount but Pb was not detected in all sample. 4. Fluoride concentrations were the range of $0.13\pm0.03\~0.42\pm0.03ppm$.

• Korean Journal of Community Nutrition
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• v.1 no.3
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• pp.346-353
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• 1996

The anthropometric measurements, nutrient intake, concentrations of minerals in scalp hair and urine and urinary 5-hydroxyindoleacetic acid(5-HIAA) of 30 autistic children not taking psychoactive drugs and 30 nonautistic control children were determined. The autistic children were taking significantly lower amounts of vitamin A, niacin, ascorbic acid and iron. The intake of vitamin A, niacin, and iron in autistic children were found to be 22$\%$, 75$\%$ and 58 of RDA, respectively. The decreased anthropometric measurements in height and weight of autistic children seems partly due to lower intake of these micronutrients. The food intake in vitamin and mineral group of autistic children was significantly lower. It is probably related to decreased intake of fruit in autistic children. There was no toxicity of cadmium and aluminum in both groups according to their contents in scalp hair. Autistic children showed elevated levels of hair calcium and zinc but lowered levels of copper and iron. The urinary excretion urinary excretion of 5-HIAA.

• The Plant Pathology Journal
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• v.36 no.5
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• pp.398-405
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• 2020

Nutrient manipulation is a promising strategy for controlling plant diseases in sustainable agriculture. Although many studies have investigated the relationships between certain elements and plant diseases, few have comprehensively explored how differing mineral nutrition levels might affect plant-fungal pathogen interactions, namely plant susceptibility and resistance. Here, we systematically explored the effects of the seven mineral elements that plants require in the greatest amounts for normal development on the susceptibility of soybean plants (Glycine max) to Fusarium oxysporum infection in controlled greenhouse conditions. Nitrogen (N) negligibly affected plant susceptibility to infection in the range 4 to 24 mM for both tested soybean cultivars. At relatively high concentrations, phosphorus (P) increased plant susceptibility to infection, which led to severely reduced shoot and root dry weights. Potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), and iron (Fe) induced plant resistance to infection as their concentrations were increased. For K and Ca, moderate concentrations had a positive effect on plant resistance to the pathogen, whereas relatively high doses of either element adversely affected plant growth and promoted disease symptoms. Further experiments were conducted, assessing disease suppression by selected combinations of macro-elements and Fe at screened concentrations, i.e., K (9 mM) plus Fe (0.2 mM), and S (4 mM) plus Fe (0.2 mM). The disease index was significantly reduced by the combination of K plus Fe. In conclusion, this systematic investigation of soybean plant responses to F. oxysporum infection provides a solid basis for future environmentally-friendly choices for application in soybean disease control programs.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.560-574
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• 1997

The present study was undertaken to investigate the crystal growth onto human enamel mineral and synthetic hydroxyapatite(HA) seeds in media resembling the enamel fluid composition. Effects of fluoride at high concentrations on the precipitation were also examined in a bench-top crystal growth model adopting a miniaturized reaction column. The Ca, P and F concentrations and pH values of the inlet and outlet solutions were determined. The recovered solid samples were weighed to assess the amount of minerals precipitated during the experimental period, and finally viewed under a scanning electron microscope. Remarkable findings were that 1) both biological and synthetic seeds with the same total surface areas yielded similar amounts of crystal growth, 2) the amount of crystal growth was accelerated in a manner depending on fluoride concentrations in the media, 3) SEM observations disclosed that without the addition of fluoride, precipitation of thin, plate-like OCP crystals became prominent, but by increasing the fluoride concentration(beyond 1ppm F), rod-like crystals having a pointed edge were most frequently observed, without any evidence for precipitation of the plate-like crystals. Furthermore, the dimension of rod-like crystals was increased in proportion to fluoride concentrations, 4) there was no difference in the morphological feature of precipitated mineral phase upon seeding between human enamel seed and synthetic HA seed. The overall results support the view that the seeded crystal growth model is of value to gain insight into the mechanism of enamel crystal growth under fluoride regimens.

• Economic and Environmental Geology
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• v.29 no.6
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• pp.725-732
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• 1996

To assess soil distribution patterns of heavy metals in agricultural environments, we have measured the concentrations of six metals from surficial soils of three different groups divided on the basis of the surrounding environment: (1) soil group I-cultivated soils within the purely agricultural regions, (2) soil group II-both cultivated and uncultivated soils near various livelihood facilities, and (3) soil group III-mainly cultivated soils near major polluting sources. The mean concentrations for the three soil groups were found in the range as follows: 0.12~0.15 (Cd), 4.94~6.08 (Pb), 0.05~0.11 (Hg), 2.82~3.50 (Cu), 4.69~7.82 (Zn), and 0.36~0.78 (As) ppm. Examination of data distribution trends indicates that the concentrations determined from the relatively unpolluted soil environs (groups I and II) were comparable not only between each other but also with those reported previously in background soil environs of Korea. The concentration data for the soil group III were however found to be much higher than the rest two groups. Unlike the direct comparison of the magnitudes of concentrations, results of a regression analysis exhibited much different patterns: it was seen that the correlation patterns for soil group I were rather analogous to those of soil group III. The similarities in correlation patterns between groups I and III along with the lack of correlations in soil group II suggest that soil characteristics such as whether being cultivated or not are important factors affecting soil distributions of heavy metals.

• The Korean Journal of Quaternary Research
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• v.21 no.2
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• pp.69-73
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• 2007

Inorganic geochemical and mineralogical analyses from the trench sediments of the Hwayang wetland were carried out to verify the wet/dry conditions during 6000 - 5000 yr BP and abnormal event of 6300 yr BP of Korean west coast. Lithostratigraphy, mineralogy and major element concentrations of the sediments of the trench indicate that during 6000 - 5000 yr BP, a wet/dry conditions might be repeated at an interval of 200 years. Carbonate minerals precipitated with the decrease of water depth in the lake or wetland after about 6000 yr BP. On the other hand, the sediments coarser in mean grain size and larger in standard deviation were corresponded with periods of 6300 yr BP and 6230 yr BP. Especially, such a feature of grain size distribution of 6300 yr BP appears in other wetlands situated in the west coast, e.g., Hwangsan wetland and Cheollipo coastal wetland. During the period, the coarse sediments seem to have been delivered by a high energy like storming.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.2
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• pp.133-138
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• 1998

Plasma and milk samples of 24 periparturient Holstein cows were collected from 1 week prepartum to 10 week postpartum to measure the effects of parity on mineral status in periparturient cows. Cows were fed mainly mixed ration with the concentrate supplement during the experimental period to meet nutrient requirement of dairy cattle for TDN, protein, and minerals, Plasma Ca of cows decrease as parity increased, but plasma Mg, K, Fe and Zn were lowest in the first lactation cows. Plasma inorganic P, Na, and alkaline phosphatase were not affected by the parity. Plasma Ca, Fe and Zn of cows decreased at parturition, but plasma Mg increase. Plasma Ca of the first, second and third and more lactation cows at parturition were 9.65, 8.96, and 8.92 mg/dl, respectively. Colostral Ca, P, Mg, Na, and Zn were highest in the first lactation cows, although colostrum yield was lower. Milk yield from 1 to 10 weeks postpartum was lowest in the first lactation cows, but mineral concentrations in milk were not affected by the parity.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.47-53
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• 2015

PURPOSES: The scaling of a concrete surface caused by the combined effects of frost and de-icing salts is one of the main reasons for the need to repair transportation infrastructures in cold-climate regions. This study describes the results of attempts to determine the scaling resistance of concrete incorporating mineral admixtures such as fly ash, GGBFS, and silica fume, and subjected to the actions of frost and salt. METHODS : Conventionally, to evaluate the fundamental properties of concrete, flexural and compressive strength measurements are regularly performed. Based on the ASTM C 672 standard, concrete is subjected to 2%, 4%, and 8% $CaCl_2$ salt solutions along with repeated sets of 50 freeze/thaw cycles, and the scaling resistance was evaluated based on the mass of the scale and a visual examination. RESULTS : It was observed that silica fume is very effective in enhancing the scaling resistance of concrete. Meanwhile, concrete incorporating GGBFS exhibited poor resistance to scaling, especially in the first ten freeze/thaw cycles. However, fly ash concrete generally exhibited the maximum amount of damage as a result of the frost-salt attack, regardless of the concentrations of the solutions. CONCLUSIONS: It can be concluded that the scaling resistance of concrete is highly dependent on the type of the mineral admixture used in the concrete. Therefore, to provide a durable concrete pavement for use in cold-climate regions, the selection of a suitable binder is essential.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.4
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• pp.517-532
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• 2021

Safe geological disposal of spent nuclear fuel (SNF) requires knowledge of the deep hydrochemical characteristics of the repository site. Here, we conducted a set of deep hydrochemical investigations using a 750-m borehole drilled in a model granite system in Wonju, South Korea. A closed investigation system consisting of a double-packer, Waterra pump, flow cell, and water-quality measurement unit was used for in situ water quality measurements and subsequent groundwater sampling. We managed the drilling water labeled with a fluorescein dye using a recycling system that reuses the water discharged from the borehole. We selected the test depths based on the dye concentrations, outflow water quality parameters, borehole logging, and visual inspection of the rock cores. The groundwater pumped up to the surface flowed into the flow cell, where the in situ water quality parameters were measured, and it was then collected for further laboratory measurements. Atmospheric contact was minimized during the entire process. Before hydrochemical measurements and sample collection, pumping was performed to purge the remnant drilling water. This study on a model borehole can serve as a reference for the future development of deep hydrochemical investigation procedures and techniques for siting processes of SNF repositories.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1422-1426
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• 2008

The purpose of this study was to test characteristics between normal and autistic children via comparison of nutrient intakes, hair mineral, blood free radical, and serotonin contents. A total of 50 children aged 3-9 were divided into two main groups of normal control children (n=22) and autistic children (n=28) tested by child psychiatrist. The nutrient intakes by 24-hour recall method were no significantly different between the two groups. The concentrations of toxic mineral, such as cadmium (Cd) and lead (Pb) in hair of autistic children were significantly higher, while concentration of antioxidant mineral (Cu, Zn, Fe) was lower than that of normal children. The autistic children had significantly higher concentrations of blood free radical than that of normal children. No significant difference was observed in serotonin concentration between the two groups. Our results suggest a possible role of increased toxic mineral and free radical, both of which may be relevant to the pathophysiology of autism in children with developmental delay.