• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.783-790
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• 2003

Tetranychus urticae Koch and Panonychus ulmi Koch were identified as quarantine pests in apple samples and were controlled soon after the commercial treatment of methyl bromide (MeBr) and with irradiation doses $(0.5{\sim}3kGy)$ after irradiation. The physical qualities of apples, such as rotting, withering, weight changes, hardness, and color, were apparently affected by MeBr. Furthermore, more than 2 kGy irradiation resulted from the lapse of storage time. Associated with the physical qualities of stored apples, irradiation and fumigation for quarantine purposes were more adequate after 40 days of storage at $0{\pm}1^{\circ}C\;(85{\pm}2%\;RH)$ immediately following harvest, rather than soon after harvest. Less than 1 kGy irradiation, based on its accumulated control effect on pests, can potentially be applied as a quarantine procedure without causing significant changes in the physical qualities of fresh apples, in contrast to MeBr.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.538-545
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• 1991

This study measured the daily intake and excretion of sodium and potassium of eight 20-26years old college men during four weeks by means of analyzing their food intake, urine and feces, keeping their normal living pattern and body weight. This study also compared the actual measurement value of sodium and potassium intake by atomic absorption spectrophotometer with the conversion value of them by food table. The results are as follows ; Daily mean sodium intakes conversed ($2.36{\pm}0.03g/day$) was about 63% lower than those intakes meansured($6.36{\pm}0.13g/day$). Daily mean potassium intakes conversed($1.71{\pm}0.03g/day$) was not different of sodium and potassium were $5.49{\pm}0.19g/day\;and\;1.33{\pm}0.08g/day$, respectively. Daily mean fecal excretions of sodium and potassium were $0.24{\pm}0.02g/day\;and\;0.45{\pm}0.03g/day$, respectively. Mean prooportion of Na/K in urine was $4.3{\pm}0.1$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.704-711
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• 2011

Traditionally, mistletoes have been used as immunostimulant for the management of certain diseases such as cancer with high profile immune depleting potentials. In order to examine the safety of the 20 kGy irradiated cold water extract powder of mistletoes, we performed a 90-day repeated-dose toxicity study with ICR mice. The mice were treated with daily doses of the 20 kGy irradiated cold water extract powder of mistletoes by gavage at 0, 20, 100, and 500 mg/kg/day for 90 consecutive days. We recorded clinical signs of toxicity, body weight, organ weights, histological changes in target organs, hematology, and clinical blood chemistry analysis data for all mice. There were no significant changes in body and organ weights during the experimental period. The hematological analysis and clinical blood chemistry data revealed no toxic effects from the 20 kGy irradiated cold water extract powder of mistletoes. Pathologically, neither gross abnormalities nor histopathological changes were observed between the control and treated mice of both sexes. Collectively, these data suggest that the 20 kGy irradiated cold water extract powder of mistletoes have a high margin of safety.

• Journal of Periodontal and Implant Science
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• v.36 no.4
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• pp.797-808
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• 2006

Objective : The purpose of this study was to evaluate the physicochemical properties and cytocompatibility of microporous, spherical biphasic calcium phosphate(BCP) ceramics with a 60/40 $hydroxyapatite/{\beta}$ -tricalcium phosphate weight ratio for application as a bone graft substitute. Materials and Methods : Microporous, spherical BCP granules(MGSB) were prepared and their basic characteristics were compared with commercially available BCP(MBCP; Biomatlante, France) and deproteinized bovine bone mineral(Bio-Oss; GBistlich-Pharma, Switzerland, BBP; Oscotec. Korea), Their physicochemical properties were evaluated by scanning electron microscopy, X-ray diffractometry, Fourier-transform infrared spectroscopy, inductively coupled plasma atomic emission spectrometer, and Brunauer-Emmett-Teller method. Cell viability and proliferation of MC3T3-El cells on different graft materials were evaluated. Results : MGSB granules showed a chemical composition and crystallinity similar with those in MBCP, they showed surface structure characteristic of three dimensionally, well-interconnected micropores. The results of MTT assay showed increases in cell viablity with increasing incubation times. At 4d of incubation, MGSB, MBCP and BBP showed similar values in optical density, but Bio-Oss exhibited significantly lower optical density compared to other bone substitutes(p <0,05). MGSB showed significantly greater cell number compared to other bone substitutes at 3, 5, and 7d of incubation(p <0,05), which were similar with those in polystyrene culture plates. Conclusion: These results indicated the suitable physicochemical properties of MGSB granules for application as an effective bone graft substitute. which provided compatible environment for osteoblast cell growth. However, further detailed studies are needed to confirm its biological effects on bone formation in vivo.

• The Korean Journal of Zoology
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• v.8 no.1
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• pp.1-7
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• 1965

The short-necked clam is distributed widely in Korean tidal flats and it is a much an important bivalve quantitatively as to control the production of the tidal flat. The shell of this clam tends to show remarkable morphological variations depending on the habitat. Under a seemingly favorable condition for the growth , the color pattern of shell of the clam is clear and obvious and having less weight and elongated shape, the ratios of shell length to both height and width are small . On the contrary , when the environment appears to be an unfavorable one, the shell is found to be heavy and stunted with smudgy color pattern. If this correlation between could be a basis for the judgement in suitability of growth environment for the clam. In the Ikawazu Bay, Japan, it is revealed that the elongated shell is produced from the coast outside of the Bay (1) , the stunted from the esturay (2) and the intermediate from the floodgate area (3) and the middle of the Bay (4). Followings are the results obtained from the morphological investigation of the claim in this Bay. 1. Relationship between the shell length and the largest shell rib length is linear and between the shell length and the shell width is also linear but with a critical point at the shell length of 17-20 mm. The ratio between the width and the largest rib length at a given shell length increases with the order of 1, 3, 4, and 2. 2. A gradual decreases of the ratio of the shell length to the largest rib length is observed when the former is less than 17-18 mm, and this ratio increases with the shell of longer. Also there is a different range of this ratio in each different location ; the greatest range in 2, the smallest in 1 and 4 being in between. 3. A similar biometric finding is apparent with the ratio between the length and width of the shell and the order in value is 2, 4, 1 and 3. 4. The ratios between the length and the largest rib length of elongated and stunted shell are 0.84-0.86 and 0.89-0.92, respectively , and those between the length and width are 0.40-0.51 and 0.49-0.58, respectively. 5. Generally , the elongated short necked clam shells are products of the tidal flat of good circulation of sea water with high salinity and smaller fluctuations of salinity and temperature within a day. The stunted shells are produced for tidal flats of opposite of above conditions.

• Macromolecular Research
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• v.12 no.1
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• pp.127-133
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• 2004

We have studied the surface micelle formation of polystyrene-b-poly(2-vinyl pyridine) (PS-b-P2VP) at the air-water interface. A series of four PS-b-P2VPs were synthesized by anionic polymerization, keeping the PS block length constant (28 kg/㏖) and varying the P2VP block length (1, 11, 28, or 59 kg/㏖). The surface pressure-area ($\pi$-A) isotherms were measured and the surface morphology was studied by atomic force microscopy (AFM) after Langmuir-Blodgett film deposition onto silicon wafers. At low surface pressure, the hydrophobic PS blocks aggregate to form pancake-like micelle cores and the hydrophilic P2VP block chains spread on the water surface to form a corona-like monolayer. The surface area occupied by a block copolymer is proportional to the molecular weight of the P2VP block and identical to the surface area occupied by a homo-P2VP. It indicates that the entire surface is covered by the P2VP monolayer and the PS micelle cores lie on the P2VP monolayer. As the surface pressure is increased, the $\pi$-A isotherm shows a transition region where the surface pressure does not change much with the film compression. In this transition region, which displays high compressibility, the P2VP blocks restructure from the monolayer and spread at the air-water interface. After the transition, the Langmuir film becomes much less compressible. In this high-surface-pressure regime, the PS cores cover practically the entire surface area, as observed by AFM and the limiting area of the film. All the diblock copolymers formed circular micelles, except for the block copolymer having a very short P2VP block (1 kg/㏖), which formed large, non-uniform PS aggregates. By mixing with the block copolymer having a longer P2VP block (11 kg/㏖), we observed rod-shaped micelles, which indicates that the morphology of the surfaces micelles can be controlled by adjusting the average composition of block copolymers.

• Applied Biological Chemistry
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• v.11
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• pp.185-188
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• 1969

This experiment was carried out to investigate on the growth, yield behavior of phosphorus at different stage of growth under the different cultivating conditions in rice plants. The results obtained were as follows; 1) The phosphorous contents was increased in the direct-sowing plots of the rooting time and the early stage of tillering, while in the middle and the later stage of growth, the transplanting plots was increased. 2) In the moisture contents, the direct-sowing plots was more increased than the transplanting plot in the rooting time and the early stage of tillering, while in the later stage of growth, the transplanting plots was increased. 3) The plant height and the weight of dry matter were also increased in the direct-sowing plots of the early stage of tillering, on the other hand, after that the transplanting plots was increased. 4) In the yield of grain, the transplanting plots was increased about 15% compared with the direct-sowing plots.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.5
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• pp.1-17
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• 2002

The immobilization and consolidation of the model coatings based on the plastic pigment and latex binder of known particle sizes were theoretically Studied in terms of the dense random packing of binary spheres and varying extent of latex film shrinkage. The porosity of the model coatings was calculated based on three proposed latex shrinkage models: Maximum, Minimum, and Linearly Decreasing Latex Shrinkage. The increasing extent of latex shrinkage was calculated up to the critical pigment volume concentration(CPVC) as a function of plastic pigment volume fractions, and the maximum latex shrinkage was estimated from the CPVC. Also, the number of pores and the average equivalent spherical pore diameters were calculated based on those proposed models. The opacity and gloss of the model coatings on polyester films were measured and their porosity was also determined by a simple coat weight-thickness method. As expected, various coating structure-property-composition relationships, such as opacity, gloss, porosity, etc., were shown to exhibit sharp transitions near the CPVC. The CPVC values determined by the opacity, gloss, and porosity vs. PVC relationships, respectively, agreed very well with each other. Especially, the CPVC's determined by the opacity and porosity vs. PVC curves were identical. The comparison between the theoretically calculated and experimental porosity values showed that the intermediate value between the maximum and minimum latex shrinkage would best fit the experimental porosity data. The effect of plastic pigment particle size on the optical properties and porosity of model coatings was also studied and it was observed that the coating opacity and porosity increased with increasing plastic pigment particle size, but the gloss decreased. The ink gloss of the uncalendered model coatings applied onto commercial sheet offset coated papers was shown to be affected by both the coating gloss and porosity: the higher the coating gloss, the higher the ink gloss, but the higher the coating porosity, the lower the ink gloss. Their printability was also studied in terms of the number of passes-to-fail and the rate of ink setting as a function of both plastic pigment volume fractions and plastic pigment particle sizes. A minimum crack-free temperature(MCR) of latex-bound coatings was proposed to better predict the behaviors of latexes as coating binders. The wet state of model coating dispersions, the surfaces of consolidated model coatings, and their internal structure were examined by both electron and atomic force microscopy, and their micrographs were found to be consistent with our immobilization and consolidation models.

• Journal of Nutrition and Health
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• v.53 no.6
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• pp.663-675
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• 2020

Purpose: The aim of this study was to measure the sodium content of the solid and liquid components of soup-based dishes (SBD) including Korean soup, stew, noodle/dumplings, and watery kimchi and to compare the sodium content in the dishes from home, schools, and restaurants in Seoul. Methods: The dishes were divided into 3 groups, namely home, restaurant and school food. We separated the dishes into solid and liquid to measure the weight, salinity, and sodium content. The sodium content of the dishes was analyzed using inductively coupled plasma atomic emission spectrometry. Results: The proportion of sodium content in the liquid component of SBD were 65.2%-66.7% in soup, 49.8%-61.2% in stew, 48.7%-56.7% in noodle/dumpling, and 43.7%-73.2% in watery kimchi. The sodium content per 100 g of the whole dishes of the same kind from the schools was significantly lower than that from the restaurants and home. However, there was no significant difference in sodium content per 100 g of whole dishes between the restaurants and home. The sodium content per 100 g of liquid in the same kind of dishes from the schools was significantly lower than those from the restaurants and home, and that from home was significantly lower than from the restaurants. Conclusion: The sodium content of the liquid in SBD accounted for at least about half of the total sodium content of the whole dishes. It is important to establish a separate database with the sodium content in the solid and liquid portions of SBD and to evaluate how much liquid and/or solid would be consumed to estimate individual sodium intake more accurately. Also, it should be noted that the sodium content varies with the origin of the dishes, whether dishes were from home, restaurants, or schools.

• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.233-240
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• 2022

Research on the presence or absence of radiation shielding for FDM-type filaments has recently begun to be studied, but filaments with shielding capabilities are not sold in Korea, and not studies yet. Therefore, in this research, we will use HDPE (High Density Polyethylene) as a base material, select bismuth as a reinforcing material to manufacture a composite filament, evaluate the shielding ability, and provide basic data for the development of a radiation shielding composite material using 3D printing.A filament is produced by mixing Bismuth with an effective atomic number 83 with HDPE of PE series and adjusting the content of Bismuth to 20% wt, 30% wt, 40% wt. Compounded filaments were evaluated for their physical properties and shielding capabilities by ASTM evaluation methods. As the bismuth content increases, the density, weight, and tensile strength increase, and the shielding capacity is confirmed to be excellent. As a result of the radiation shielding capacity evaluation, it was confirmed that HDPE (80%) + Bi (20%) showed a shielding rate of 82% at 60 kV and a shielding rate of up to 94% or more at 40% bismuth content. In this study, we confirmed that it was possible to produce a radiation shield that is lighter than the metal particle-containing filaments. Furthermore, that have been shield radiation by using HDPE + Bi filaments, and radiation in the medical and radiation industries. The possibility of using it as a shielding complex was confirmed.