• Analytical Science and Technology
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• v.33 no.6
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• pp.245-251
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• 2020

Lead (Pb) has been shown to be a useful tracer of contamination sources and geochemical processes such as age dating and crustal evolution. These studies require a chromatographic technique for Pb separation from geological samples. This paper presents a comparison study on the effect of eluent concentration between 6M HCl and 8M HCl on the separation of Pb from Pb resin. The results showed that the separation of Pb using 6M HCl as the eluent was not effective compared to the separation using 8M HCl. To verify this method, we measured the Pb isotopic compositions of the Pb isotopic standard (NIST NBS981) and geological reference materials (BCR-2, GSP-2, and JG-1a) using a thermal ionization mass spectrometer (TIMS). The results correspond well with the reported values within the error range, implying that this method can be useful.

• Analytical Science and Technology
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• v.22 no.2
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• pp.136-140
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• 2009

To improve the carbon recovery yield of chemical pretreatment in soil and sediment for $^{14}C$ age dating using AMS (Accelerator Mass Spectrometry), we have developed ultrasonic method in chemical pretreatment to replace with stirring method which has been generally used in each step of humic acid extraction for soil and sediment samples. Extraction conditions such as ultrasonic power, temperature and reaction time have been optimized. Six times higher carbon recovery yield could be obtained from low carbon content samples using ultrasonic method. We also compared the dating results by AMS obtained using ultrasonic method with the ages of samples treated by the stirring method. It was found that this new method could be applied to the pretreatment process of low carbon content samples for AMS age dating without effects on the dated ages, and with highly improved carbon recovery yields.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.527-533
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• 2005

Purpose : Long-term administration of anticonvulsants in children with epilepsy may cause short stature, hypocalcemia and low bone mineral density. This study was performed for the early detection of abnormal bone metabolism in children with epilepsy on taking anticonvulsants. Methods : Thirty children aged 5 to 16 years who were diagnosed with epilepsy were enrolled in this study. All had taken anticonvulsants for more than one year. Bone mineral density of lumbar vertebra was measured by dual-energy X-ray absorptiometry. Serum calcium, phosphorous, alkaline phosphatase, 25-hydroxycholecalciferol[$25(OH)D_3$], parathyroid hormone, and urine deoxypyridinoline were measured as biochemical bone markers. Bone age and body mass index were also calculated. Results : Bone minreal density, body mass index, bone age, and height were significantly decreased in two female patients who had taken two antiepileptic drugs for more than four years and they also had chronic diseases such as cerebral palsy with microcephaly, encephalomalacia, and microcephaly with atrial septal defect. Bone mineral density had significant positive correlations with body mass index(P<0.01) and bone age(P<0.01). Conclusion : This study showed chronic medication of anticonvulsants in children may cause low bone mineral density and short stature. Bone age and body mass index could be the important surrogate markers to find the population at risk. More studies, including a large study population and long term cohort study, will be required.

• Journal of the Korea Society of Computer and Information
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• v.24 no.9
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• pp.97-102
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• 2019

Several studies have recently demonstrated that skeletal muscle is an endocrine organ releasing and expressing myokines acting in an endocrine or paracrine manner. Irisin is a hormene-like myokine induced after physical exercise by muscle fibers. It was primarily recognized as a molecule able to advance the "browning response" in white adipose tissue, however, it has been recetly identified that irisin also has a fundamental role in the control of bone mass. We study evidence for its possible skeletal effects, including the fundamental role that irisin is involved in the control of bone mass, with beneficial effects on geometry and cortical mineral density. As loss of muscle mass and bone density occurs with immobility, metabolic disease and aging, future studies researching the efficacy of irisin in reversing muscle wasting and restoring bone would be important to proving irisin as a molecule that combines helpful effects for treating muscular atrophy and osteoporosis in elderly people.

• The Journal of the Korea Contents Association
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• v.8 no.10
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• pp.241-250
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• 2008

The interest in male osteoporosis is increasing as the incidence of osteoporotic fractures has increased not only in female but also in male due to the increase of old age population thanks to the development of medical science and science in general. Therefore, this study is to find factors related to bone mineral density of male older than 40 years old, to investigate the incidence of the male osteoporosis and to provide a basic result for prevention and medical treatment for the male osteoporosis. The incidence of the osteopenia and the osteoporosis at L-spine was 45% and 12.9% respectively and the incidence of them at femur was 51.9% and 7.63% respectively, among male older than 40 years old who took a medical examination. It was higher than the existing study results conducted to male older than 50 years old in USA and Europe. The incidence of them at both of L-spine and femur showed a significant difference depending the age groups. As the age increases, the average bone mineral density decreases at both of L-spine and femur. And as the weight increases and the body mass index is higher, the incidence of the osteoporosis decreases. There was no significant relation with the incidence of the osteoporosis depending on the exercise, the smoking and the drinking, but the number of exercise, smoking and drinking changes the quantity of bone and are factors influencing the bone mineral density of male person.

• Journal of Life Science
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• v.18 no.9
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• pp.1230-1238
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• 2008

The purposes of this study was to identify the effects of regular training on body composition, bone mineral density and growth factors by taekwondo training program in the children. Subjects were aged 11$\sim$13 years. There was classified two groups (experiment group 12, control group 12), total 24. Measured items for this study were body composition (weight, percent body fat, body mass index), lumbar (L2, L3, L4), femur (neck, trochanter, ward's triangles) bone mineral density and growth factors (growth hormone, IGF-I, IGFBP-III) in the 12weeks before and after. Results of this study were as follows; In the body composition, there were showed significant differences on the weight, percent body fat and body mass index level between groups. In the bone mineral density, there were showed significant differences on the lumbar 2, 3, and femur neck, femur trochanter, femur ward's triangles level between groups. In the growth factors, there were showed significant differences on the growth hormone, IGF-I, and IGFBP-III level between groups. This study showed that an 12weeks taekwondo training program affected in a positive effects in almost of items in trained children.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.317-323
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• 2002

Mineral medicines are single or mixtures of minerals and rocks which have been used to treat disease. Recently, their application has been increased by emphasizing the physical properies of the medicines, in addition to their chemical properies. In this study, mineralogical, chemical, spectroscopic and magnetic properties were measured using X-ray diffraction analysis, X-ray fluorescence spectrometry, Ff-Infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass magnetic susceptibility. Experiments were done using these properties to evaluate application of traditional mineral medicines such as Yanggiseok, Yeonok and Eumgiseok. Mineralogical study proves that Yanggiseok, generally known as tremolite, consists of actinolite. Yeonok for medical usage mostly consists of fine grained tremolite. Eumgiseok is mainly composed of vermiculite and minor kaolinite and halloysite. Yeonok and Yanggiseok, belong to the amphibole group among inosilicates and both have similar emission power properties. The intensity of emission power, calculated from FT-IR measurements, follows in the order of Yeonok, Yanggiseok and Eumgiseok at 40$^{\circ}$C and Yanggiseok, Yeonok and Eumgiseok in such order at 150$^{\circ}$C. As a result of NMR analysis after 20 days in distilled water, the three mineral medicines decreased in the following order; Eumgiseok, Yanggiseok and Yeonok. However, the same minerals decreased in the order of Eumgiseok, Yeonok and Yanggiseok after 80 days. In response temperature, magnetic susceptibility of Yanggiseok and Eumgiseok systematically increased by heating to 25$^{\circ}$C, 100$^{\circ}$C and 700$^{\circ}$C. Magnetic susceptibility of Yeonok shows a decreasing pattern due to heating.

• Korean Journal of Community Nutrition
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• v.8 no.6
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• pp.927-937
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• 2003

This study was conducted to investigate dietary and other factors affecting bone mineral density (BMD) in Korean premenopausal women. Seventy-eight premenopausal women who visited the Health Promotion Center for health examinations volunteered to participate in this study. They were divided into two groups according to their bone status as shown by their T-scores: a non-osteoporotic group and a osteoporotic group. The results are as follows: The mean BMDs of the lumbar spine and femoral neck were 1.21$\pm$0.02$g/cm^2$ and 0.97$\pm$0.04$g/cm^2$, respectively. The BMD levels of the osteoporotic group were significantly lower than those of the non-osteoporotic group (p<0.001, respectively). The heights of the women in the osteoporotic group were significantly lower than those of the non-osteoporotic group (p<0.01) however, their body weights did not show any significant differences although they tended to be lower. The mean daily intake of energy was 1720$\pm$52㎉. When the nutrient intake was compared with the Korean recommended dietary allowances (RDA), calcium, Fe, vitamin A and riboflavin intakes were lower than the RDA. Their was no significant difference in the nutrient intake of the non-osteoporotic group and osteoporotic group except for the intakes of protein, fat and niacin. Their was no significant difference between the non-osteoporotic group and the osteoporotic group and all were within the normal range. However, the serum alkaline phosphatase level of the osteoporotic group was significantly higher than that of the non-osteoporotic group (p<0.001). Height measurements showed positive correlations with lumbar spine bone mineral density (LBMD, r=0.332, p<0.01) however there was no correlation with femoral neck bone mineral density (NBMD). Age, age at menarche, body weight, body mass index (BMI) and obesity showed no correlation with BMD. The BMD of the lumbar spine was significantly and positively related to the intake of niacin and vitamin C (r=0.236, p<0.05; r=0.274, p<0.05). Serum levels of calcium and phosphorus showed negative correlations with LBMD (r=-0.698, p=0.0001, r=-0.503, p=0.0001, respectively). The results suggested that the BMD of the lumbar spine was positively related to the intake of niacin and vitamin C in premenopausal women. Therefore, this study confirmed that one of the most effective ways to minimize bone loss would be have a higher intake of niacin and vitamin C rich foods and engaging habitually in physical activity may have a beneficial effect on BMD in the Premenopausal Period.

• The Korean Journal of Ecology
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• v.25 no.6
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• pp.399-403
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• 2002

Cellulose mass loss by cellulose filter papers was measured for 3 time (35 days, 70 days, 105 days) incubation during the growing season (from May to September 2002) with different tree density and after fertilization in a Japanese larch (Larix leptolepis) plantation. Cellulose mass loss rates were significantly different between tree density types and fertilization treatments during the study periods. After 105 day incubation of cellulose filter paper, cellulose mass loss rates were significantly higher in the low tree density (70.1 $\%$) than in the high tree density (49.9$\%$). Cellulose mass loss rates averaged 62.8$\%$ in the fertilization and 58.9% in the unfertilization treatments during the same periods. However, cellulose mass loss was not significantly different between the forest floor and the mineral soil layer except for 35 day incubation. The results indicate that cellulose decomposition rates are a useful index to express differences in organic matter decomposition activity in different tree density and after fertilizer treatments.

• Economic and Environmental Geology
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• v.23 no.3
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• pp.309-322
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• 1990

The accelerated industrialization of Korean economy over the last couple of decades has brought an era of mass consumption of mineral commodities. This increased consumption has been satisfied mainly by imports from abroad. South Korea has about 50 useful mineral commodities for the mineral industry, among 330 kinds of minerals described. In 1988 the self-sufficiency ratio of domestic demand for 44 non-fuel(metallic and non-metallic) minerals as a whole was no more than 29 percent. The ratio for 26 non-metallic minerals was much higher, about 66 percent. On the other hand, the ratio for 18 metallic minerals was relatively very low, about 6.3 percent. The correlation between GNP and mineral consumption in South Korea shows well the slow down patterns during the last two decades.