• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.95-110
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• 1982

For the purpose of investigation to identify the quantities of heavy metals contained in the tissues of the Korean people, a series of analyses was conducted with atomic absorption spectrophotometry to measure the amount of lead, cadmium and copper distributed in various tissues, such as brain, liver, kidney, heart, lung, spleen, large intestine, hair, muscle, fat, stomach, costal cartilage, blood and urine, obtained from 30 cadaverous bodies who were believed not exposed to the said heavy metals during their life time either occupationally or therapeutically. 1. Lead content: Inter-individual difference was noted in lead contents in each tissue, vis., the average content of lead in hair was the highest with $14.90{\pm}9.74ppm$. The next was in costal cartilage that contained $5.56{\pm}3.86ppm$. The average contents of lead in liver, kidney and muscle were the lowest in value, showing $1.11{\pm}0.92ppm,\;0.73{\pm}0.48ppm\;and\;0.06{\pm}0.06ppm$, respectively, The lead contents in tissues of children under the age of 10 were significantly lower than those of adults, and the higher values were shown in males than in females in general. The lead contents in most of the tissues such as hair, costal cartilage, kidney, lung, fat, stomach, large intestine, heart, muscle and urine were well correlated with age. 2. Cadmium content: The average content of cadmium in kidney appeared to be the highest of other tissues showing $20.72{\pm}9.82ppm$, and liver came next with the value of $1.17{\pm}0.99ppm$. It was estimated that 83.9% of the total cadmium absorbed into the body was stored in kidney, 4.796 in liver, and the remaining 11.4% was distributed in the rest of the tissues. Cadmium contents in tissues showed difference between both sexes showing higher values in the females than in the males, which was quite contrary to the lead content. Cadmium contents in tissues steadily increased in amount with age, showing a significant correlation with age in all tissues. 3. Copper content: The average content of copper in hair was the highest with $10.36{\pm}2.21ppm$, and liver came next with $6.31{\pm}1.24ppm$. The copper that was absorbed into the body was distributed in each tissue: 29.9% in hair, 18.2% in liver, $5{\sim}11.0%$ in brain, heart and kidney, and $3.0{\sim}3.5%$ in stomach, blood, and lung. The copper contents in tissues of children under the age of 10 showed significantly higher values in liver, kidney, heart and large intestine than those of the adults. The copper contents in brain, costal cartilage and fat were well correlated with age showing the highest correlation coefficient of 0.870 (p<0.01) in brain tissue. There was no difference in copper contents in tissues between both sexes, and the values were, in general, lower than those for Japanese.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.187-191
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• 2009

'Campbell Early', a major grape cultivar, occupies more than 70% of cultivated vineyard areas, however, recommendable standard management system of soil environmental conditions has not been developed yet in Korea. The consideration for the correlation between fruit quality and soil condition in the vineyard is required in the efficient management system of soil. This study was carried out to investigate the optimum soil environmental conditions for 'Campbell Early' grape production with high quality. The results from analyses of correlation between them were used to develop soil management guideline for promoting efficiency in grape production. Soil properties were analyzed from 120 vineyards in Hawsung, Sangju, Yeongdong, Gimcheon, Yeongju, and Yeongwol, major grape production regions. Because there is neither coloring disorder nor delayed coloration in grape production of 'Campbell Early', relative contribution of soil hardness and solid phase to fruit quality and fruit weight was analyzed. Among the soil properties, while cation and soil hardness affected sugar content at the level of 39.3% and 36.8%, respectively, saturated hydraulic conductivity, solid phase, and cation exchange capacity (CEC) showed relatively low contribution to sugar content in the vineyard. The sugar content in grapes was influenced more critically by the chemical properties than the physical ones in the soil of vineyards. While soil hardness and solid phase affected grape weight at the level of 27.8% and 26.0%, respectively, phosphate content, organic matter content, and cation showed low contribution to grape weight. Grape guality such as sugar content and grape weight was affected highly by cation and organic matters. Therefore, cation and organic matter content of soil contributed to fruit quality at the level of 33.8% and 15.5%, respectively, in the vineyard.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.756-762
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• 2011

This study was conducted to investigate the effects of moisture content on microbiological stability and texture characteristic of dry-cured ham. The moisture content of dry-cured hams was adjusted to 35% (C) or 45% (T) and then vacuumpackaged after slicing to a 1 inch thickness. All packaged dry-cured hams were stored at $10^{\circ}C$ for 3 mon, and physicochemical analyses and a sensory evaluation were conducted to verify the quality of dry-cured hams during four different storage periods. Moisture content was significantly higher in T (44.89%) compared to that in C (35.03%). However, crude fat content was higher in C (14.08%) than that in T (11.11%). The pH, salinity, and shear force were higher in C than those in T, and dry-cured hams derived from C seemed to provide low lipid oxidation stability during storage. In contrast, T showed high CIE $L^*$, CIE $a^*$ and CIE $b^*$, and aw values when compared to dry-cured hams from C. Total plate counts and Lactobacillus tended to increase with the increase in storage period, and both were lower in T than those in C after 1 mon of storage. Our results indicate that 45% moisture content improved dry-cured ham quality as compared to that of dry-cured hams containing 35% moisture.

• Journal of Educational Research in Mathematics
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• v.25 no.2
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• pp.207-223
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• 2015

This study aims to find ways for securing continuity of elementary mathematics curriculum and kindergarten curriculum. To do this, we considered the status of 'mathematical exploration' in Nuri curriculum and analysed the correspondence of content-domains and the continuity between Nuri curriculum for ages three to five and 2009 revised national elementary mathematics curriculum, based on the reconstructed achievement criteria. The result of these analyses reveals that the classification of five content-domains both for 'mathematical exploration' of Nuri curriculum and for 2009 revised national elementary mathematics curriculum coincides. We also recognized the reconstructed achievement criteria which are considered as reverse continuity or as discontinuity of Nuri curriculum and 2009 revised national elementary mathematics curriculum in all the five content domains. The former means being lower in levels or reduction in ranges from Nuri curriculum to elementary one. The latter means that some reconstructed achievement criteria are included in only one of the two curriculum. Based on these results, we suggested several ways to secure the continuity between Nuri curriculum and 2009 revised national elementary mathematics curriculum in the perspective of mathematics education.

• Journal of Dairy Science and Biotechnology
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• v.38 no.3
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• pp.161-167
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• 2020

Cheese pizzas fortified with casein phosphopeptide (CPP) and calcium were subjected to an in vitro digestion to assess whether CPP could prevent the precipitation of calcium. The total calcium content of the cheese pizzas was adjusted to 1,000 mg per pizza (~370 g) with the addition of calcium originating from eggshells. Two levels of trypsin-digested caseins (367 and 459 mg), with a CPP content of ~20%, were added to each pizza. The in vitro digested pizzas were then centrifuged and the supernatant was mixed with Na₂HPO₃ at 37℃ to estimate the possible soluble effect of CPP on calcium. After 24 h of reaction, the solution was centrifuged and the calcium content in the resultant supernatant was analyzed by inductively coupled plasma-atomic emission spectroscopy. One-way statistical analyses showed that CPP had a positive effect on the solubilization of calcium against phosphate (p<0.05). Cheese pizza supplemented with 459 mg of CPP powder was able to prevent precipitation of calcium by 98.8%, whereas no CPP-added cheese pizza solubilized 86.4% of the calcium. A sensory test was also carried out, revealing that panelists could not discern the bitter taste of the CPP added to the pizzas.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.740-746
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• 2006

The proximates, vitamin C, minerals, and fatty acids of five potato cultivars were evaluated by AOAC methods, the hydrazine method, ICP-AES, and gas chromatography, respectively. The proximate analyses; vitamin C, reducing sugar, and soluble solid contents; and mineral and fatty acid compositions were significantly different among the five cultivars. The Superior cultivar contained a higher carbohydrate content and higher Ca/P ratio and lower levels of crude protein and Na. The Atlantic cultivar contained significantly higher amount of energy, carbohydrate, reducing sugar, vitamin C, SEA, and MUFA, and significantly lower amount of minerals and PUFA. The Shepody cultivar contained significantly higher amount of carbohydrate and MUFA, and significantly lower amount of soluble solid, vitamin C, and SFA. In addition, the P, Fe, Mg, Cu, and Al levels were significantly higher in Shepody, and Zn content was significantly lower. The Jopung cultivar contained significantly higher levels of moisture and Na, and significantly lower levels of soluble content, reducing sugar, carbohydrate, crude protein, and fat. Finally, the Namsuh cultivar contained significantly higher amount of soluble solid, crude protein, K, Mg, and Al, and significantly lower amount of reducing sugar.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.4
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• pp.73-79
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• 2003

With the variation of Ag concentration in bath, current density, duty cycle, additive and agitation for electroplating of Sn-Ag solder, the compositions and the morphologies of solder were studied. It was possible to controll Ag content in Sn-Ag solder by varying Ag concentration in bath and current density. The microstructure size of Sn-Ag solder decreased with increasing current density. Duty cycle of pulse electroplating and quantity of additive affected on Ag content of deposit and surface roughness. In this work eutectic Sn-Ag solder bumps with fine pitch of 30 $\mu\textrm{m}$ and height of 15 $\mu\textrm{m}$ was formed successfully. The Ag content of electrodeposited solder was confirmed by EDS and WDS analyses and the surface morphologies was analyzed by SEM and 3D surface analyzer.

• International Journal of Concrete Structures and Materials
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• v.10 no.sup3
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• pp.19-31
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• 2016

The objective of this paper is to investigate the effect of thickness and moisture on temperature distributions of reinforced concrete walls under fire conditions. Toward this goal, the first three wall specimens having different thicknesses are heated for 2 h according to ISO standard heating curve and the temperature distribution through the wall thickness is measured. Since the thermal behavior of the tested walls is influenced by thickness, as well as moisture content, three additional walls are prepared and preheated to reduce moisture content and then tested under fire exposure. The experimental results clearly show the temperatures measured close to the fire exposed surface of the thickest wall with 250 mm thickness is the highest in the temperatures measured at the same location of the thinner wall with 150 mm thickness because of the moisture clog that is formed inside the wall with 250 mm of thickness. This prevents heat being transferred to the opposite side of the heated surface. This is also confirmed by the thermal behavior of the preheated walls, showing that the temperature is well distributed in the preheated walls as compared to that in non-preheated walls. Finite element models including moisture clog zone are generated to simulate fire tests with consideration of moisture clog effect. The temperature distributions of the models predicted from the transient heat analyses are compared with experimental results and show good agreements. In addition, parametric studies are performed with various moisture contents in order to investigate effect of moisture contents on the thermal behaviors of the concrete walls.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1201-1205
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• 2009

Corn starches with different amylose contents were enzymatically modified using Thermus aquaticus 4-$\alpha$-glucanotransferase ($TA{\alpha}GTase$). Upon the enzyme treatment, the chain-length distributions of isoamylolytically debranched products became broader [degree of polymerization (DP): 3-40] than those of untreated corn starches. In addition, a variety of cycloamyloses (CAs) with different sizes were formed by the glucanotransfer activity of $TA{\alpha}GTase$. CAs with DP 5-40 were detectable in all of the $TA{\alpha}GTase$-treated corn starches. From the results of high-performance anion-exchange chromatography and high-performance size-exclusion chromatography analyses, it was suggested that the amount of CAs produced by the enzyme treatment increased as the amylose content of the starches increased. Thus, we concluded that the extent of modification of starch molecules was enhanced in proportion to amylose content by the transfer activity of $TA{\alpha}GTase$. This finding could be useful for developing an efficient process of CA production using this enzyme.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.353-368
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• 2020

This research investigates how pre-service music teachers demonstrated pedagogical content knowledge (PCK) and self-efficacy during a 16-week Music Education Course. 37 pre-service music teachers underwent peer mentoring, and prepared teaching guides and class teaching demonstrations. At the end of the course, the 37 participants' teacher self-efficacy and PCK components (namely pedagogical knowledge, representational knowledge, subject matter knowledge, assessment knowledge, student characteristics knowledge, curriculum knowledge, and context and social knowledge) were assessed. Data on their self-efficacy and PCK were gathered through a group interview and their self-reflection journals, and analyzed as phenomenological experience research. Analyses of the data show that pre-service music teachers acquired diverse knowledge. It also showed that peer mentoring enhanced the pre-service music teachers' self-efficacy, enabling them to prepare teaching guides and confidently demonstrate classes. Thus, diverse opportunities in research and practical class demonstrations contributed to pre-service music teachers' PCK and self-efficacy.