• Journal of the East Asian Society of Dietary Life
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• v.4 no.3
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• pp.21-30
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• 1994

The relationship between bone mineral density and the environmental factors were investigated from the view point of preventing osteoporosis in Korean pubescent girls. The effects of calcium, nutrient intake, physical activity on total bone mineral density, lumbar spine and femoral bone mineral density and total bone mineral content were evaluated 33 healthy pubescent girls aged 14∼16y. A convenient method was used to assess nutritional and energy intake and calcium index was used together. Calcium intake in childhood was estimated by asking whether subjects usually drank milk as children. Eating habits data and history of menstruation were obtained by questionnaire and interview. Average energy expenditure was calculated. Bone mineral density and content were measured by dual energy x-ray absorptiometry using a Lunar DPX＋Scanner (Lunar, Madison, WI). The lumbar spine(L2∼L4) and three sites in the proximal femur (femoral neck, trochanteric region, and Ward's triangle)were measured. Height and weight were measured, and the body mass index(BMI) was derived from the formula : BMI=kg/㎡ Statistical analysis was performed by simple correlation using the SAS package. The mean calcium intake (736mg) was below the RDA of 800mg/d. Twelve percent of the total subjects did not drink milk at all because they did not like the taste. Skipping meals, low calcium intake and low energy intake were significantly correlated with the low BMD. Also the data indicate that girls who reported drinking milk with every meal during childhood had significantly higher bone densities than girls who reported drinking milk less frequently. The results suggest that milk consumption in childhood appears to be needed not only for growth and development, but possibly also to assure an optimal peak of bone mass and thus greater latitude for the maintenance or skeletal integrity in the face of bone losses. There was a highly significant correlation between the total BMD and overall level of physical activity. Body weight was a better predictor of total BMD than was and other factor. Simple mechanical loading may explain why body weight, but total BMC was positively relatd to height. Conclusively, increasing calcium intake and physical activity in the pubescent girls could influence BMD.

• Journal of Nutrition and Health
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• v.35 no.8
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• pp.863-869
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• 2002

Soy isoflavones have been hypothesized to exert hormonal effects and to enhance bone mineral density in postmenopausal women. To test this hypothesis, we studied the effects of soy isoflavones supplements on bone mineral density and sex hormones (serum estradiol, sex hormone-binding globulin and testosterone) in 47 postmenopausal women. There were 24 participants in the treatment group and 23 in the control group. The treatment group consumed the isoftavones extract capsule daily (which contained 90 mg of soy isoflavones) for 12 weeks. The study compared pre- and post-isoflavones intake in the following areas: physical examination, diet survey, bone mineral density and serum sex hormone levels. The average age of the treatment group was 64.63 years and that of the control group was 66.48 years. There were no significant differences between the two groups in terms of height, weight, and body mass index. Both groups maintained regular diet patterns in terms of their average daily nutrient intake. There was no significant difference between the treatment group (18.49 mg) and the control group (21.27 mg) in terms of daily isoflavones intake based on diet. The 12-week analysis of bone mineral density change after taking isoflavones supplements demonstrated no significant differences in the following : lumbar spine BMD (0.82 g/$\textrm{cm}^2$ in pre versus 0.81 g/$\textrm{cm}^2$ in post), femoral neck BMD (0.58 g/$\textrm{cm}^2$ in pre versus 0.57 g/$\textrm{cm}^2$ in post) in the treatment group. There was no significant difference in serum estradiol in the isoflavones treatment group. The subjects indicated no significant difference in serum testosterone in the isoflavones treatment group. But the subjects indicated a significant difference in sex hormone-binding globulin (60.04 nmol/L in pre versus 52.39 nmol/L in post) in the isoflavones treatment group at the levels of p < 0.05. The significant decrease in sex hormone-binding globulin did indicate the need for long-term study on isoflavones supplementation as well as its positive effect on bone mineral density.

• Korean Journal of Remote Sensing
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• v.23 no.4
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• pp.287-295
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• 2007

A mineral potential map showing the distributions of potential areas for exploration of undiscovered mineral deposits is a kind of predictive thematic maps. For any predictive thematic maps to show reasonably significant prediction results, validation information on prediction capability should be provided in addition to spatial locations of high potential areas. The objective of this paper is to apply prediction rate curves to the estimation of prediction probability of future discovery. A case study for Au-Ag mineral potential mapping using geochemical data sets is carried out to illustrate procedures for estimating prediction probability and for an interpretation. Through the case study, quantitative information including prediction rates and probability obtained by prediction rate curves was found to be very important for the interpretation of prediction results. It is expected that such quantitative validation information would be effectively used as basic information for cost analysis of exploration and environmental impact assessment.

• Journal of the Korean Dietetic Association
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• v.11 no.1
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• pp.86-94
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• 2005

This study was conducted to examine bone mineral density and factors which effect on bone mineral density such as daily nutrients intake, age, menarch age and physical condition among healthy female college students in Daegu area from April 20, to May 20, 2004. 1. Average age was 20.5$\pm$0.96 years old, average height was 160.9$\pm$4.30㎝, and average weight was 55.9$\pm$7.67㎏. Body mass index was 21.6$\pm$2.91㎏/㎡, body fat was 25.6$\pm$5.79％, menarche age was average 12.5$\pm$1.1 years old and WHR(waist/hip circumference ratio) was 0.8$\pm$0.01㎝/㎝. 2. Average level of bone mineral density(T-score -0.56$\pm$0.91) was in normal range. But, 11 persons(24.4％) are over T-score -1.0, 33 persons(73.4％) were within -1.0 - -2.5 and one person(2.2％) was under -2.5. It is very anxious level for Osteopenia-low bone mass, as research result shows 73.4% of the subject of examine on the level of Osteopenia. 3. Daily calorie intake was 2,550㎉ and each nutrient intake, compared to the seventh recommended dietary allowances for korean, was as follows ; Calorie 112％, protein 123％, calcium 78％, phosphorus 137％, iron 68％, vitamin A 101％, vitamin $B_1$ 141％, vitamin $B_2$ 95％, niacin 107％, vitamin C 128％ and zinc 120％. The ratio of calcium to phosphorus(Ca/P) is 0.66, low compared to RDA, but phosphorus intake is so high compared to RDA that precautions should be taken. The ratio of calcium to protein(Ca/Protein) is 8.55. 4. Menarche age and bone mineral density of calcaneus showed positive correlation and body mass index(BMI) indicated positive correlation. Age, height, weight. WHR and physical activity coefficient all do not indicate any significant correlation with bone mineral density. 5. Intake of Calorie, Ca, Ca/p ratio, carbohydrate and fat intake were positively correlated and, protein was negatively correlated, and Fe, Na, P and cholesterol were negatively correlated with BMD. These results indicate that average bone mineral density of subjects was in normal range, but subjects in the stage of osteopenia-low bone mass are many and bad effects are expected to have on their bone mineral density after menopause. Therefore, in order reach maximal bone mineral density, they should improve the balance between calcium and phosphorus and reduce salt intake. And it is thought that education and profound studies on relevant factors affecting the genesis of bone mineral density should be made.

• Journal of Soil and Groundwater Environment
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• v.25 no.2
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• pp.16-23
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• 2020

In this work, ²²²Rn activity, major dissolved ions, and microbial community in ground- and surface waters were investigated to characterize groundwater inflow to the stream located in an urban area, Daejeon, Korea. The measured ²²²Rn activities in groundwater and stream water ranged from 136 to 231 Bq L^-1 and 0.3 to 48.8 Bq L^-1, respectively. The spatial distributions of ²²²Rn activity in the stream strongly suggested groundwater inflow to the stream. The change of geochemical composition of the stream water indicated the effect of groundwater discharge became more pronounced as the stream flows downstream. Furthermore, microbial community composition of the stream water had good similarity to that of groundwater, which is another evidence of groundwater discharge. Although groundwater inflow could not be estimated quantitatively in this study, the results can provide useful information to understand interactions between groundwater and surface water, and determine hydrological processes governing groundwater recharge and hydrogeological cycles of dissolved substances such as nutrients and trace metals.

• Restorative Dentistry and Endodontics
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• v.43 no.1
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• pp.11.1-11.10
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• 2018

Objectives: This study aimed to introduce the use of laser-induced breakdown spectroscopy (LIBS) for evaluation of the mineral content of root canal dentin, and to assess whether a correlation exists between LIBS and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) methods by comparing the effects of irrigation solutions on the mineral content change of root canal dentin. Materials and Methods: Forty teeth with a single root canal were decoronated and longitudinally sectioned to expose the canals. The root halves were divided into 4 groups (n = 10) according to the solution applied: group NaOCl, 5.25% sodium hypochlorite (NaOCl) for 1 hour; group EDTA, 17% ethylenediaminetetraacetic acid (EDTA) for 2 minutes; group NaOCl+EDTA, 5.25% NaOCl for 1 hour and 17% EDTA for 2 minutes; a control group. Each root half belonging to the same root was evaluated for mineral content with either LIBS or SEM/EDS methods. The data were analyzed statistically. Results: In groups NaOCl and NaOCl+EDTA, the calcium (Ca)/phosphorus (P) ratio decreased while the sodium (Na) level increased compared with the other groups (p < 0.05). The magnesium (Mg) level changes were not significant among the groups. A significant positive correlation was found between the results of LIBS and SEM/EDS analyses (r = 0.84, p < 0.001). Conclusions: Treatment with NaOCl for 1 hour altered the mineral content of dentin, while EDTA application for 2 minutes had no effect on the elemental composition. The LIBS method proved to be reliable while providing data for the elemental composition of root canal dentin.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.214-217
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• 2013

Twenty-nine Korean wheat cultivars were analyzed for 8 important minerals (Cu, Fe, Mn, Zn, Ca, K, Mg and P) using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). A hierarchical cluster analysis (HCA) was applied to classify wheat cultivars, which has a similarity in mineral compositions. The concentration ranges of the micro-minerals Cu, Fe, Mn, and Zn: 0.12~0.71 mg/100 g, 2.89~5.89 mg/100 g, 1.65~4.48 mg/100 g, and 2.58~6.68 mg/100 g, respectively. The content ranges of the macro-minerals Ca, K, Mg and P: 31.3~46.3 mg/100 g, 288.2~383.3 mg/100 g, 113.6~168.6 mg/100 g, and 286.2~416.5 mg/100 g, respectively. The HCA grouped 6 clusters from all wheat samples and a significant variance was observed in the mineral composition of each group. Among the 6 clusters, the second group was high in Fe and Ca, whereas the fourth group had high Cu, Mn and K concentrations; the fifth cluster was high in Zn, Mg and P. The variation in mineral compositions in Korean wheat cultivars can be used in the wheat breeding program to develop a new wheat cultivar with high mineral content, thus to improve the nutritional profile of wheat grains.

• Analytical Science and Technology
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• v.19 no.1
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• pp.45-49
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• 2006

Drilled sediment core was acquired from Jinheung catchment which was located at Jeollabuk-do Jeongeup city. Elements concentration variation were studied by neutron activation analysis using sediment core by divided 1 cm depth interval. The concentration of major element such as Na, K were increased but Fe was decrease with depth. Minimum elements concentration and particle size were observed at 17 cm depth. This depth was considered 1969 year which was great dry year recorded from the rain fall data and the sedimentation rate was calculated $0.197g{\cdot}cm^{-2}{\cdot}year^{-1}$.

• Environmental and Resource Economics Review
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• v.15 no.4
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• pp.713-740
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• 2006

In this paper, we examine what factors should be considered in cost-benefit analysis of a resource-developing project as cos and benefit item. According to this study, the reduction in forest product value and the reduction in function to clean air pollution should be included as a environmental cost. However, the reduction in recreation function and function in cleaning water need not to be included. We also calculated a cost-benefit of developing project for lime mineral of A company by applying these factor just mentioned. This paper concluded that the net benefit of this project is positive and the range of the value is from 689,900million won to 1,784,000million won.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.9
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• pp.52-57
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• 2010

The analysis of a crack in a bone-like material is performed numerically. The bone-like material is hierarchically structured and each hierarchy is structured by mineral platelets and protein matrix through staggered arrangement. Mechanical behavior of the composite can be analyzed using tension shear chain model. The Dugdale model is adopted to evaluate the fracture energy of Bone-like material. The fracture energy dissipation is assumed to concentrate within a strip near the crack tip along the prospective crack path. Fracture criterion of the bone-like material is estimated by using J integral. Effects of hierarchical level, ratio of elastic modulus of mineral to protein, aspect ratio of mineral platelet and volume fraction on J integral are investigated. It is found that the J integral decreases as elastic modulus ratio and hierarchy level increase. It is also shown that the J integral increases as the volume fraction and aspect ratio decrease.