• Radiation Oncology Journal
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• v.20 no.2
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• pp.186-192
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• 2002

Purpose : Measurement of transmission dose is useful for in vivo dosimetry. In this study, previous algorithm for estimation of transmission dose was modified for use in cases with tissue deficit. Materials and Methods : The beam data was measured with flat solid phantom in various conditions of tissue deficit. New algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. The algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients using multiple sheets of solid phantoms. Results : The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ${\pm}1.0\%$ in most situations and within ${\pm}3.0\%$ in experimental settings with irregular contours mimicking breast cancer treatment set-up. Conclusion : Developed algorithm could accurately reflect the effect of tissue deficit and irregularly shaped body contour on transmission dosimetry.

• Journal of the Korean earth science society
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• v.33 no.4
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• pp.329-336
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• 2012

In September 2009, a perfectly preserved fossil of a dinosaur egg nest was discovered in the Cretaceous formations of the Aphaedo area in Shinan, Jeollanam-do, South Korea. In order to estimate the age of dinosaur eggshells and the depositional age of the Cretaceous sediments in Aphaedo area, a whole-rock K-Ar dating was carried out on volcanic pebbles showing a sedimentary structure contemporaneous with the Aphaedo strata, acidic tuffs overlaying the strata conformably, and acidic dike rocks intrude to both of them. Volcanic rocks observed in the strata are 3-20 cm in diameter as pebbles found in lenticular conglomerate and pebble bearing mudstone strata. K-Ar whole-rock dating was performed on six different volcanic pebbles which show a sedimentary structure contemporaneous with the dinosaur egg nest contained in the strata, and all samples show Late Cretaceous ages: Cenomanian ($97.6{\pm}1.9$Ma), Coniacian ($87.6{\pm}1.7$ Ma), Santonian ($84.5{\pm}1.7$Ma) or Campanian ($82.5{\pm}1.6$, $77.3{\pm}1.5$, $75.7{\pm}1.5$ Ma). The K-Ar whole-rock age of acidic tuffs overlaying the Cretaceous formation conformably was estimated to be Campanian ($79.2{\pm}1.6$ or $77.3{\pm}1.5$Ma), when the dating was carried out under the same conditions. The acidic dike intruding both Cretaceous formation and acidic tuff showed a K-Ar whole-rock age of $70.9{\pm}1.4$Ma (Campanian). Therefore, the depositional age of the Cretaceous formation in the Aphaedo area and the time when dinosaurs lived in the study area are considered to be 77-83 Ma. Such results indicate that the ages of dinosaur eggshells from Aphaedo area can be correlated with the ages of the Seonso Formation (81Ma) with dinosaur egg nest fossils and the Uhangri Formation (79-81Ma) with dinosaur, pterosaur and web-footed bird tracks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1344-1350
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• 2016

The purpose of this study was to evaluate the effect of edible coating on hygroscopicity and quality characteristics of a freeze-dried Actinidia arguta snack. Freeze-dried A. arguta snacks were coated with various edible coating materials such as albumin, dextrin, and whole soy flour. There were no significant effects of coating on major quality properties such as moisture content, water activity, yield, water soluble index, water absorption index, and rehydration properties of all samples. Compared with non-coated samples, edible coated samples effectively inhibited hygroscopicity as a function of hygroscopic time. The samples coated with dextrin showed lower hygroscopicity than the other coated samples. In addition, the effects of edible coating treatment on hardness, total phenolic content, and antioxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity were investigated. Edible coated samples had higher hardness, total phenolic content, and antioxidant activity than the non-coated samples as a function of hygroscopic time. Among edible coating materials, dextrin was the most effective coating material. Dextrin as an edible coating material for freeze-dried A. arguta snack may help to prevent hygroscopicity and extend market quality and shelf-life during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1106-1113
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• 2017

The objective of this study was to determine the quality characteristics of fried yakgwa and baked yakgwa prepared with different amounts of P. frutescens powder. Moisture contents of fried yakgwa were 7.05%, and moisture content of baked yakgwa with different amounts of P. frutescens powder were 12.42~10.44% and decreased with higher amount of P. frutescens powder. This result can be attributed to loss of water in yakgwa in the course of the fried process. Although the degree of expansion of baked yakgwa was lower than that of fried yakgwa, size and shape of yakgwa were maintained. Yakgwa is appropriate as a cookie type product. Crude lipid contents of fried yakgwa were higher than those of baked yakgwa due to the exchange reaction of water and fat during the fried process. Energy of fried yakgwa was 501 kcal and was higher than that of baked yakgwa with different amounts of P. frutescens powder. This greatly affected the fat content of each sample. Energy of baked yakgwa increased with higher amount of P. frutescens powder due to the characteristics of the ingredients or jasoyeop. For chromaticity determination, L values of fried yakgwa were lower, but a, and b values were higher than those of baked yakgwa, and L, a, and b values decreased when P. frutescens powder increased. Texture measurement showed that hardness, cohesiveness, chewiness, gumminess increased with higher amounts of P. frutescens powder, whereas springiness decreased. The antioxidant activities of fried yakgwa measured based on DPPH scavenging activity were higher than those of baked yakgwa with 0%~0.2% P. frutescens powder and lower than those of baked yakgwa with 0.3%~0.4% P. frutescens powder. In the sensory evaluation, baked yakgwa with 0.1% addition of P. frutescens powder showed the highest preference in terms of overall acceptance, and 0% addition of P. frutescens powder showed the highest preference in terms of color and flavor. These results suggest that P. frutescens powder may be a useful ingredient in baked yakgwa to improve quality and sensory properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1041-1048
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• 2012

Shiitake mushroom (SM; Lentinus edodes) are cultivated and consumed in many Asian countries including Vietnam, China, Japan, Korea, and Thailand. In Asia, SM are mainly dried and used as flavoring. The aim of this study was to compare the effects of SM created with different drying processes, such as oven-dried and sun-dried, on the antioxidative and antigenotoxic effects. Raw and dried SM were extracted with acetone, ethanol, methanol, and hot water. The antioxidant effects of SM were evaluated by determining total phenolic content, DPPH radical scavenging activity (RSA), an ORAC assay, and a cellular antioxidant capacity (CAC) assay. The inhibitory effect of SM on oxidative stress-induced DNA damage in human leukocytes was evaluated by a Comet assay. The total phenolic content of raw SM extracted with methanol and of that extracted with water were significantly higher than the dried SM. Among the water extracts, the $IC_{50}$ for DPPH RSA of raw and sun-dried SM were significantly higher than that of oven-dried SM. Sun-dried SM showed the most potent ORAC value at 50 g/mL. The CAC against $AAPH^-$ induced oxidative stress in HepG2 cells, and $H_2O_2$ induced DNA damage were effectively protected against by all SM extracts. These results suggest that unprocessed SM are the best antioxidants, and that the sun-dried method would be the best option to use in terms of antioxidant activity and the antigenotoxic effect.

• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.24-33
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• 2020

In excavated bronze artifacts, corrosion products of various shapes and colors are observed due to multiple corrosion factors coexisting in the burial environment, and these corrosion products can constitute important data not only in terms of long-term corrosion-related information, but also in connection with preservation of artifacts. As such, scientific analysis is being carried out on the corrosion layer and corrosion products of bronze artifacts, and the corrosion mechanism and the characteristics of corrosion products elucidated, which is essential for interpreting the exposed burial environment and its association with corrosion factors inside the burial environment. In this study, after classifying excavated bronze artifacts according to alloy ratio and fabrication technique, comprehensive analysis of the surface of corrosion artifacts, corrosion layer, and corrosion products was carried out to investigate the corrosion mechanism, formation process of the corrosion layer, and characteristics of corrosion products. The study designated two groups according to alloy ratio and fabrication technique. In Group 1, which involved a Cu-Sn-Pb alloy and had no heat treatment, the surface was rough and external corrosion layers were formed on a part, or both sides, of the inside and the outside, and the surface was observed as being green or blue. α+δ phase selection corrosion was found in the metal and some were found to be concentrated in an empty space with a purity of 95 percent or more after α+δ phase corrosion. The Cu-Sn alloy and heat-treated Group 2 formed a smooth surface with no external corrosion layer, and a dark yellow surface was observed. In addition, no external corrosion layer was observed, unlike Group 1, and α corrosion was found inside the metal. In conclusion, it can be seen that the bronze artifacts excavated from the same site differ in various aspects, including the formation of the corrosion layer, the shape and color of the corrosion products, and the metal ion migration path, depending on the alloy ratio and fabrication technique. They also exhibited different corrosion characteristics in the same material, which means that different forms of corrosion can occur depending on the exposure environment in the burial setting. Therefore, even bronze artifacts excavated from the same site will have different corrosion characteristics depending on alloy ratio, fabrication technique, and exposure environment. The study shows one aspect of corrosion characteristics in specific areas and objects; further study of corrosion mechanisms in accordance with burial conditions will be required through analysis of the corrosive layer and corrosive product characteristics of bronze artifacts from various regions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.238-247
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• 2006

The purpose of this study was to evaluate school dieticians' performance of nutritional quality control, and further to establish effective and objective standards of nutritional quality control. Data for this study came from 200 school dieticians' responses in the Chungbuk area. The total quality management (TQM)-based questionnaire was structured. The questionnaire consisted of the following four fields (1) performance of nutritional quality control, (2) performance of stepwise food production to maximize nutrient preservation rate, (3) management of documents and records related to nutritional quality control, and (4) other relating matters. The items of the questionnaire were measured on a five-point Likert scale which ranged from 'strongly agree' to 'strongly disagree'. First, the analysis indicated that school dieticians performed 'least' on human resource management', 'mediocre' on nutritional quality control, and best on 'leadership'. Second, the analysis on performance of stepwise food production to maximize nutrient preservation rate showed that dieticians considerably endeavored to maximize nutrients of cooked food, but it was found out that the most of nutrient destruction can be caused by heating during cooking. Third, the result showed that the systematic use of documents and records for nutritional quality control was not sufficiently accomplished, especially in the production phase of food. In addition, the measure by the Pearson correlation coefficient indicated that there was a significant relationship between performance of nutritional quality control and performance of stepwise food production to maximize nutrient preservation rate, and between performance of nutritional quality control and management of documents and records related to nutritional quality control. Finally, the findings of this study suggest that more effort should be exerted to carefully establish TQM-based standards for the improvement of nutritionary quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1558-1566
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• 2015

The purpose of this study was to examine dietitians' perception of importance about standards of foodservice management associated with long-term care hospital accreditation. This study was carried out through a postal survey consisting of 500 questionnaires, and 157 returned questionnaires were used in the statistical analysis. The results were summarized as follows. Average scores of perception of importance were 4.54/5 points in foodservice production management domain, 4.56/5 points in foodservice facilities management domain, and 4.70/5 points in foodservice sanitation domain. The average scores of importance of long-term care hospitals without accreditation were significantly (P<0.05) lower than those of hospitals with accreditation in items of 'establishment of ventilation equipment in kitchen', 'establishment of hand-washstand in toilet (warm-water, soap)', 'setup of sterilizing foothold in entrance of kitchen and toilet', 'division and use of knife, chopping board, gloves, and utensils before and after cook', 'establishment of cleaning plan and cyclic practice', and 'recording of receiving diary'. Results indicate that there is a need to supplement a casebook of regulations by suggesting detailed and critical limits in the case of below average points of importance. A manual, including HACCP standards for foodservice management of long-term care hospitals, is needed, along with education and webpage for comparing notes on accreditation of long-term care hospitals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.401-408
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• 1985

In order to develop new types of product which can offer a sanitary and preservative duality, and convenience to consumers in marketing and cooking particularly in urban area, two processing methods of ready-to-cook food materials with dark fleshed fishes like sardine and mackerel were investigated. A method applied, in this work, is processing of ready-to-cook sardine meat "surimi" in which sardine meat is treated with alkaline solution to stabilize myofibrillar proteins, washed thoroughly with water to remove soluble components, and added with a proper amount of polyphosphate and sorbitol to enforce the functional property of meat such as water holding capasity, elasticity, and gel strength. The textural properties of fish meat paste made from the "surimi" meat were greatly dependent upon the stability of myofibrillar proteins and the elimination of water soluble components. The salt soluble proteins of sardine meat were so unstable in post-mortem stage that the gel forming ability was lost within 3 days at $5^{\circ}C$ storage and 2 to 3 weeks even at $-20^{\circ}C$ although the freshness was well kept for a week at $5^{\circ}C$ and several months of storage at $-20^{\circ}C$. A proper way of treatment to keep the proteins stable was that fish meat must be washed with $0.4\%$ sodium bicarbonate solution followed by 3 to 4 times washing with water. This resulted in removal of $80\%$ water soluble proteins and 50 to $60\%$ lipids. The addition of polyphosphate and sorbitol affected the stability of proteins during the storage of "surimi" meat. When phosphate and sorbitol were added in the ratio of $0.3\%:\;0.3\%,\;0.6\%:\;3\%,\;0.6\%:\;6\%,\;0:\,0.3\%\;and\;0.3\%:\;0$, the gel forming ability terminated in 35 days, 21 days, 14 days, 14 days, and 14 days of storage at $-30^{\circ}C$, respectively, while that of the control was 7 days. And it was also noteworthy that at least 8.0 mg/g of salt soluble protein nitrogen content was required for gel formation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.52-59
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• 1986

As one of trials to process instant sardine foods which can be preserved at room temperature, three kinds of products were prepared as seasoned-dried product (control, C), liquid smoked seasoned-dried product(S) and antioxidant treated seasoned-dried product(E), and their processing conditions and quality stability during storage were examined. Raw sardines were dressed, steamed and then filleted. The sardine fillets were seasoned with the mixed seasoning solution containing $28.0\%$ of sorbitol, $14.0%$ of sugar, $5.6\%$ of table salt, $1.8\%$ of monosodium glutamate, $0.6\%$ of garlic powder and $50.0\%$ of water at $5^{\circ}C$ for 15 hours, and dipped for 45 seconds in $10\%$ Smoke-EZ solution. After liquid smoking, the seasoned and liquid smoked sardine fillets were dried at $45^{\circ}C$ for 4 hours, vacuum packed in laminated plastic film bag(polyester/casted polypropylene= $12{\mu}m/70{\mu}m,\;15{\times}16cm$), and finally pasteurized in water at $95^{\circ}C$ for 30 minutes. The results obtained from chemical and microbial experiments during storage are as follows : the moisture contents, water activity and pH of the products showed little change, and VBN of them slightly increased during storage. The TBA value and POV of the products (E, S) were lower than those of control product(C) considerably. In color values, L value (linghtness) decreased while a and b value (red and yellow) revealed a tendency to increase during storage. The fatty acid composition of the products were similar to those of raw sardine, the predominant fatty acids were 16:0, 20:5, 18:1 and 22:6. The products (E, S) have a good preservative effect on highly unsturated fatty acids during storage. Viable cell counts of those products were negative and histamine contents were less than 2.0 mg/100 g. Among the texture profiles, hardness, elasticity and cohesiveness of the products slightly decreased during storage. Judging from the sensory evaluations, liquid smoked seasoned-dried product(S) was the most desirable, and the products could be preserved in good condition for 40 days at $25{\pm}3^{\circ}C$.