• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.863-875
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• 2005

Bovine bone-derived bone substitutes are widely used for treatment of bone defects in dental and orthopedic regenerative surgery. The purpose of this study was to evaluate the basic characteristics of deproteinized bovine bone mineral as a bone graft substitute. Commercially available products from three different bovine bone minerals-Bio-Oss(GeistlichPharma, Switzerland), BBP(Oscotec. Korea), Osteograf/N-300(Dentsply Friadent Ceramed, USA) - were investigated. They were evaluated by scanning electron microscopy(SEM), energy dispersive X-ray spectrometer(EDS), surface area analysis(BET), and Kjeldahl protein analysis. Cell viability on different products was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay. The results of this study indicated that each bone substitute displayed distinct surface properties. Furthermore, Kjeldahl protein analysis indicated that residual crude proteins are present in deproteinized bovine bone mineral. BBP showed relatively large amount of residual protein, which indicated that the possibility of disease transmission can not be safely ruled out. Based on the results of this study, it is suggested that active quality management is strongly needed in operations that involve processing bovine bone tissue for medical use.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.491-498
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• 2005

Acid Rock Drainage(ARD) is the product formed by the atmospheric(i.e. by water, oxygen and carbon dioxide) oxidation of the relatively common iron-sulphur minerals pyrite($FeS_2$). ARD causes the acidification and heavy metal contamination of water and soil and the reduction of slope stability. In this study the generation characteristics and the prediction of ARD of various road cut slopes were studied. An attempt to classify the rocks into several groups according to their acid generation potentials was made. Acid Base Accounting(ABA) tests, commonly used as a screening tool in ARD predictions, were performed. Sixteen rock samples were classified into PAF(potentially acid forming) group and four rock samples into NAF(non-acid forming) group. The chemical analysis of water samples strongly suggested that ARD with high content of heavy metals and low pH could pollute the ground water and/or stream water.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1594-1600
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• 2010

A study was conducted to determine the dietary effects of a clay mineral (sodium bentonite, NaB) on manure gas emission, health, production, and meat characteristics of Hanwoo steers. Two diets fed to steers included a control diet (concentrate mix and rice straw) and a treatment diet (control diet+1.0% clay mineral/concentrate mix). Dietary NaB addition considerably reduced concentrations of gases ($H_2S$, $SO_2$ and $NH_3$) in the manure of Hanwoo steers. Growing steers fed NaB had similar blood profiles with the exception of lower (p<0.05) concentrations of blood alkaline phosphatase and lactate dehydrogenase. Dietary NaB addition tended to increase (p = 0.10) live weight by 30 kg at slaughtering and did not affect carcass yield and quality traits. Dietary NaB addition increased concentrations of P (p<0.01), Mg (p<0.01), Na (p<0.01), Zn (p<0.005), K (p = 0.08), Fe (p = 0.08) and Cu (p = 0.07) in the longissimus muscle compared to the control but did not affect (p>0.05) fatty acid composition. The study demonstrated that the dietary addition of a clay mineral could be effective in improving mineral bioavailability to Hanwoo steers, which could be one of the reasons for their improved performance.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.515-525
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• 2006

Survey was done to total 250 people to analyze characteristics of water quality in 5 widely used mineral water springs-(Teajosan(a), Leechungmukong(b), Onju(c), Yeongin(d), Crown(e))-in Chung-nam area and local mineral water usage. And the content of mineral and physico-chemical properties were compared in 5 sites. The largest users of mineral water spring was $40{\sim}50's$ of ages. Among those mineral water spring users, 52.5% had regular dietary habit and 32% showed improvement in lift habit after using mineral water spring. The mineral water spring users were engaged in student, housewife, professional, self-employed, etc. Those who were highly interested in health were likely to use mineral spring water more often regardless of age and occupation. Five mineral water springs differed in contents of mineral. The average content of minerals was $Ca\;28.5mg/{\ell},\;K\;1.5mg/{\ell},\;Mg\;5.3mg/{\ell},\;Na\;14.3mg/{\ell}$. 'K index' was an indicator of healthy water, and 'O index' was an indicator of tasty water. According to K indek and O index, waters of a b, c and e area were classified as 'tasty and healthy water', and water of e area had the highest values in both K and O index d area was classified as 'tasty water.'

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1066-1075
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• 1998

The use of vitamin and mineral supplements among 330 preschool children was examined for relationships with general characteristics and food habits. Mean intake of vitamin and minerals obtained from supplement use was calrulated. The percrntage of preshool children receiving vitamin-mineral supplements was 34.2% and a higher percentage of use was shown in boys(p<0.05). Among preschool children, supplement use by mother and children showed some association(p<0.05). Socio-economi factors had little influence on vitamin-mineral supplement usage. There D·ere no significant differences in. weight and height between the users and non-users. The parent's main reasons f3r providing their preschoolers with vitamin-mineral supplements were that they were unsure that the preschoolers were receving sufficient nutrients from their diet, and that they were not healthy. The reasons for not feeding their children vitamin-mineral supplements were that considered the preschoolers were eating well and were healthy, therefore vitamin-mineral supplements were not necessary. The mean vitamin intake obtained from the supplements was about 2-7 times the RDA, but the level of minerals(Ca, Fe, Zn) furnished by supplement use was 1/2 of the RDA. (Korean J Nutrition 31(6) : 1()66-1075, 1998)

• Journal of Electrical Engineering and Technology
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• v.13 no.4
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• pp.1682-1691
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• 2018

Natural ester is a suitable substitute for mineral oil and has been widely used in AC transformer in many countries. In order to further application of natural ester in direct current (DC) equipment, it is needed to investigate its long term insulation property under DC condition. In this paper, a thermal ageing experiment was conducted for both mineral oil-paper and natural ester-paper insulation. The DC breakdown and space charge characteristics of insulation paper impregnated with natural ester and mineral oil was compared. Results show that the resistivity of the paper immersed in natural ester and mineral oil both increase as the ageing goes on. While insulation paper impregnated with natural ester has higher resistivity and DC breakdown voltage than the paper impregnated with mineral oil. The DC breakdown voltage for the oil impregnated insulation paper being DC pre-stressing is higher than that without pre-stressing. The average DC breakdown field strength difference between the test with pre-stressing and without pre-stressing clearly shows that there is an apparent enhancement effect for the homo-charge injection on the DC breakdown.

• Economic and Environmental Geology
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• v.44 no.5
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• pp.345-357
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• 2011

It was carried out to the survey on the lead-zinc and tungsten occurrences in the Kau Loc mineralized belt within northern Vietnam. The lead-zinc occurrence bear the ore body parallel to the bedding of limestone formation. Assuming the surface grade and geological reserve, Pb+Zn deposit is estimated to the small to medium-sized ore deposit. On the other hand, considering the distribution of small-scale stock intruding the Devonian limestone, it is thought that the tungsten occurrence has the proper geological conditions anticipating the presence of skarn mineralization. However, there is no evidence to recognize economic feasibility in the present situation because of the absence of detailed geology and ore deposit survey on the tungsten occurrence.

• Geosciences Journal
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• v.22 no.6
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• pp.871-880
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• 2018

During and shortly after the 2017 Pohang Earthquake ($M_w$ 5.4), sand blows were observed around the epicenter for the first time since the beginning of instrumental seismic recording in South Korea. We carried out field surveys plus satellite and drone imagery analyses, resulting in observation of approximately 600 sand blows on Quaternary sediment cover in this area. Most were observed within 3 km of the epicenter, with the farthest being 15 km away. In order to investigate the ground's susceptibility to liquefaction, we conducted a trench study of a 30 m-long sand blow in a rice field 1 km from the earthquake epicenter. The physical characteristics of the liquified sediments (grain size, impermeable barriers, saturation, and low overburden pressure) closely matched the optimum ground conditions for liquefaction. Additionally, we found a series of soft sediment deformation structures (SSDSs) within the trench walls, such as load structures and water-escaped structures. The latter were vertically connected to sand blows on the surface, reflecting seismogenic liquefaction involving subsurface deformation during sand blow formation. This genetic linkage suggests that SSDS research would be useful for identifying prehistoric damage-inducing earthquakes ($M_w$ > 5.0) in South Korea because SSDSs have a lower formation threshold and higher preservational potential than geomorphic markers formed by surface ruptures. Thus, future combined studies of Quaternary surface faults and SSDSs are required to provide reliable paleoseismological information in Korea.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.217-222
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• 1995

Experiments were conducted to study the effect of IBA, mineral stone and stem hardness on rooting characteristics in mature Aloe vera plant. The rooting ability in matured Aloe vera was of highly significance when the amount of IBA treatment was increased to 5.000mg/l. The treatment of IBA 5.000mg/l, together with mineral stone(v/w 1.5 times), gave more root number, the length and the dry weight of root were, also, higher in semihard wood cutting than soft wood cutting in matured Aloe vera.

• Journal of Nutrition and Health
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• v.33 no.3
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• pp.241-249
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• 2000

The bone mineral density(vertebrae Ll-4, femoral neck, Ward's triangle and trochanter) of 160 healthy adult women aged 29-45 was measured and general characteristics, anthropomentric measurements, and dietary intake were also studied to determine the main factors affecting the bone mineral density(BMD) of adult women. The nutrient intake of the subjects was adequate to RDA level except energy, Ca, Fe, and vit A. The BMD of vertebrae L24 showed significant positive association with nutrient intake such as animal protein, P, Ca(animal) and Fe(animal). The BMD of the femoral neck correlated significantly with anthropometric measurements such as height, weight, waist circumference, hip circumference, body fat and body mass index. The BMD of both sites(vertebrae L24 and femoral neck) were significantly related to vertebrae L24 was daily Ca intake and that of femoral neck was daily energy expenditure. In conclusion, adequate nutrient intake, especially protein, P, Ca and Fe as well as increases in physical activity were suggested to prevent the loss of bone mineral density in adult women.