• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.131-138
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• 1985

The preservative effect of modified-atmosphere storage on the shelf-life of packed semi-salted and dried mackerel, Scomber japonicus, was examined. The semi-salted and dried mackerel fillets were packed in laminated plastic film bags (polyester/nylon/casted polypropylene: $12{\mu}m/15{\mu}m/60{\mu}m,\;15{\times}16cm$) filled with air (control, C), nitrogen gas (N), deoxygenized air (O) prepared by using free-oxygen absorber enclosed in the bag, in vacuum(V), and stored at $5^{\circ}C$. The quality of packed sample during the storage were examined in terms of viable cell counts of bacteria, thiobarbituric acid(TBA) value, perozide value(POV), volatile basic nitrogen(VBN), trimethylamine(TMA), adenosine triphosphate(ATP) and its related compounds and sensory evaluation. The results obtained are as follows: The pH of all the samples was in the range of $6.1{\pm}0.2$, and the contents of VBN and amino nitrogen of them increased during storage. In color values, L value(lightness) decreased while a and b values (red and yellow) revealed a tendency to increase during storage. The viable cell counts of the control sample(C) increased to $3.0{\times}10^6/g$ after 15 days storage but those of the other samples(V, N and O)were in the range of $2{\sim}6{\times}10^5/g$ after 20 days storage. The content of TMA increased during storage, but the histamine content showed a little change during storage and its content of all samples were less than 16 mg/100g. The inosinic acid(IMP) was rapidly degraded while inosine and hypoxanthine increased during storage. The TBA value of the control(C) reached a peak in 9 days and then decreased gradually while that of the sample(O) showed a little change during storage. The changes in POV of all the samples during storage showed a similar tendency to the TBA value. Fatty acid composition of raw mackerel consists of $35.6\%$ of saturated acid, $30.3\%$ of monoenoic acid and $34.2\%$ of polyenoic acid. The major fatty acid of the sample products were oleic acid($C_{18:1}$), palmitic acid($C_{16:0}$), docosahexaenoic acid($C_{22:6}$). The contents of polyenoic acid such as $C_{22:6},\;C_{20:5}$ decreased during storage while the other fatty acids showed a little change. From the results of sensory evaluation, the shelf-life of the control sample(C) was about 7 days and that of sample(V), (N) and (O) was about 15 days. It was concluded that deoxygenized atmosphere(free-oxygen absorber enclosed in the bag) was a good condition for preserving the quality of semi-salted and dried mackerel.

• Korean Journal of Heritage: History & Science
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• v.49 no.2
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• pp.172-189
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• 2016

In this research, literature research on the Odong material, mixture ratio, casting method and casting facility was conducted on contemporary documents, such as Cheongong Geamul. Also, a long sword was produced using the Odong inlay technique. The sword reproduction steps were as follows; Odong alloying, silver soldering alloying, Odong plate and Silver plate production, hilt and sheath production, metal frame and decorative elements, such as a Dugup (metal frame), production, Odong inlay assembly and final assembly. For the Odong alloy production, the mixture ratio of the true Odong, which has copper and gold ratio of 20:1, was used. This is traditional ratio for high quality product according to $17^{th}$ century metallurgy instruction manual. The silver soldering alloy was produced with silver and brass(Cu 7 : Zn 3) ratio of 5:1 for inlay purpose and 5:2 ratio for simple welding purpose. The true Odong alloy laminated with silver plate was used to produce hilt and sheath. The alloy went through annealing and forging steps to make it into 0.6 mm thick plate and its backing layer, which is a silver plate, had the matching thickness. After the two plates were adhered, the laminated plate went through annealing, forging, engraving, silver inlaying, shaping, silver welding, finishing and polishing steps. During the Odong colouring process, its red surface turns black by induced corrosion and different hues can be achieved depending on its quality. To accomplish the silver inlay Odong techniques, a Hanji saturated with thirty day old urine is wrapped around a hilt and sheath material, then it is left at warm room temperature for two to three hours. The Odong's surface will turn black when silver inlay remains unchanged. Various scientific analysis were conducted to study composition of recreated Odong panel, silver soldering, silver plate and the colouring agent on Odong's surface. The recreated Odong had average out at Cu 95.57 wt% Au 4.16wt% and Cu 98.04 wt% Au 1.95wt%, when documented ratio in the old record is Cu 95wt% and Au 5wt%. The recreated Odong was prone to surface breakage during manufacturing process unlike material made with composition ratio written in the old record. On the silver plate of the silver and Odong laminate, 100wt% Ag was detected and between the two layers Cu, Ag and Au were detected. This proves that the adhesion between the two layers was successfully achieved. The silver soldering had varied composition of Ag depending on the location. This shows uneven composition of the silver welding. A large quantities of S, that was not initially present, was detected on the surface of the black Odong. This indicates that presence of S has influence on Odong colour. Additional study on the chromaticity, additional chemical compounds and its restoration are needed for the further understanding of the origin of Odong colour. The result of Odong alloy testing and recreation, Odong silver inlay long sword production, scientific analysis of the Odong black colouring agent will form an important foundation of knowledge for conservation of Odong artifact.

• Journal of radiological science and technology
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• v.31 no.4
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• pp.401-406
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• 2008

The aim of this study is to evaluate contra-lateral breast (CLB) surface dose in Field-in-Field (FIF) technique for breast conserving surgery patients. For evaluation of surface dose in FIF technique, we have compared with other techniques, which were open fields (Open), metal wedge (MW), and enhanced dynamic wedge (EDW) techniques under same geometrical condition and prescribed dose. The three dimensional treatment planning system was used for dose optimization. For the verification of dose calculation, measurements using MOSFET detectors with Anderson Rando phantom were performed. The measured points for four different techniques were at the depth of 0cm (epidermis) and 0.5cm bolus (dermis), and spacing toward 2cm, 4cm, 6cm, 8cm, 10cm apart from the edge of tangential medial beam. The dose calculations were done in 0.25cm grid resolution by modified Batho method for inhomogeneity correction. In the planning results, the surface doses were differentiated in the range of $19.6{\sim}36.9%$, $33.2{\sim}138.2%$ for MW, $1.0{\sim}7.9%$, $1.6{\sim}37.4%$ for EDW, and for FIF at the depth of epidermis and dermis as compared to Open respectively. In the measurements, the surface doses were differentiated in the range of $11.1{\sim}71%$, $22.9{\sim}161%$ for MW, $4.1{\sim}15.5%$, $8.2{\sim}37.9%$ for EDW, and 4.9% for FIF at the depth of epidermis and dermis as compared to Open respectively. The surface doses were considered as underestimating in the planning calculation as compared to the measurement with MOSFET detectors. Was concluded as the lowest one among the techniques, even if it was compared with Open method. Our conclusion could be stated that the FIF technique could make the optimum dose distribution in Breast target, while effectively reduce the probability of secondary carcinogenesis due to undesirable scattered radiation to contra-lateral breast.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.359-367
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• 2012

This study was to evaluate the influence of dental caries prevention-related concerned and perceived in Korean adults and oral health behavior of their first child if they had children. A cross-sectional study in 1,014 adults over 19 years old were conducted in Korean adults, asked to answer a computer-assisted telephone interview regarding their oral health-related knowledge, behavior, concerned of caries prevention and child's behaviors such as frequencies of tooth brushing, chewing the xylitol gum and dental checkup. The statistical analysis was done by using the SPSS 19.0 program (IBM Co., Armonk, NY, USA). Awareness of caries prevention in the female than male, 40~49 years old age group was higher. Parents of school-age children were higher level of awareness of the dental caries prevention than other group. As knowledge and behavior of dental caries prevention were higher, the child's conduct regular oral health checkups, fluoride topical application and dental sealant was significantly higher. The higher the concerned of caries preventive, the intention of oral health behaviors and child's oral health behaviors was more increased. Awareness of caries prevention had effect on the perception of the impact of the child's oral health behaviors.

• Journal of Life Science
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• v.26 no.4
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• pp.419-430
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• 2016

Powdery mildew disease caused by Podosphaera xanthii is a major concern for Cucumis melo production worldwide. Knowledge on genetic behavior of the related genes and their modulating phytohormones often offer the most efficient approach to develop resistance against different diseases. Mildew Resistance Locus O (MLO) genes encode proteins with seven transmembrane domains that have significant function in plant resistance to powdery mildew fungus. We collected 14 MLO genes from ‘Melonomics’ database. Multiple sequence analysis of MLO proteins revealed the existence of both evolutionary conserved cysteine and proline residues. Moreover, natural genetic variation in conserved amino acids and their replacement by other amino acids are also observed. Real-time quantitative PCR expression analysis was conducted for the leaf samples of P. xanthii infected and phyto-hormones (methyl jasmonate and salicylic acid) treated plants in melon ‘SCNU1154’ line. Upon P. xanthii infection using 7 different races, the melon line showed variable disease reactions with respect to spread of infection symptoms and disease severity. Three out of 14 CmMLO genes were up-regulated and 7 were down-regulated in leaf samples in response to all races. The up- or down-regulation of the other 4 CmMLO genes was race-specific. The expression of 14 CmMLO genes under methyl jasmonate and salicylic acid application was also variable. Eleven CmMLO genes were up-regulated under salicylic acid treatment, and 7 were up-regulated under methyl jasmonate treatments in C. melo L. Taken together, these stress-responsive CmMLO genes might be useful resources for the development of powdery mildew disease resistant C. melo L.

• Journal of Life Science
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• v.18 no.2
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• pp.264-272
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• 2008

The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Acanthogobius hasta were characterized by biochemical, immunochemical and kinetic methods. The activities of LDH in skeletal muscle and eye tissues were 65.30 and 53.25 units, but LDH activities in heart and liver tissues were very low. LDH/CS (EC 4.1.3.7, citrate synthase) in skeletal muscle was the highest as 22.29. Specific activities of LDH in brain, eye and skeletal muscle were 56.45, 38.04 and 11.0 units/mg, respectively. The LDH isozymes in tissues were separated by polyacrylamide gel electrophoresis after immunoprecipitation with antiserum against $A_4,\;B_4$ eye-specific $C_4$ and liver-specific $C_4$. LDH $AC_4$ isozymes were detected predominantly in skeletal muscle, brain and eye tissues, and $B_4$ isozyme was detected in heart. Anodal eye-specific $C_4$ and cathodal liver-specific $C_4$ were coexpressed in A. hasta. The eye-specific $C_4$ isozyme showed higher activity in eye tissue, but liver-specific $C_4$ isozyme showed lower activity in liver. As a result, one part of molecular structures in $A_4\;and\;C_4,\;A_4\;and\;B_4$, and eye-specific $C_4$ and liver-specific $C_4$ were similar, but in $B_4\;and\;C_4$ were different with each other. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The LDH $A_4$ isozyme of skeletal muscle was purified in the fraction from elution with NAD+ containing buffer of affinity chromatography and eye-specific $C_4$ isozyme was eluted right after $A_4$, so the structure of eye-specific $C_4$ isozyme is similar to $A_4$. And LDH activity remained 35.22-43.47% as a result of the inhibition by pyruvate, the Michaelis-Menten constant values for pyruvate was 0.080-0.098 mM, and Vmax were 153.85 units, 35.09 units in skeletal muscle and eye, respectively. Also the $B_4$ isozyme was the thermo-stablest and $C_4$ was stabler than $A_4$ isozyme. The optimum pH of LDH was 6.5. The results mentioned above indicate that isozymes in tissues showed the properties between LDH $A_4\;and\;B_4$ isozyme as A. hasta was adapted to hypoxic conditions. Also LDH seems to function more effectively under anaerobic condition because LDH in skeletal muscle and eye tissues have high affinity for pyruvate.

• Journal of the Korean earth science society
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• v.33 no.2
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• pp.126-138
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• 2012

Ultrasonic method is widely used for the evaluation of weathering index and of degree of deterioration because it is easily applicable $in$ $situ$. The basic idea of the method is that the ultrasonic velocity decreases as a rock is being weathered. Thus, the difference of ultrasonic velocities between fresh rock and weathered rock indicates the degree of weathering. In this method, the ultrasonic velocity of fresh rock is assumed to be 5,000 m/s. However, this assumption can cause significant errors in estimating weathering index, especially in case that those rocks of the same type have a wide range of ultrasonic velocities such as in Korea. Therefore, we obtained twenty rock specimens and sixty core samples commonly used for stone cultural heritages in Korea, and measured ultrasonic velocities. From the results, we found that the ultrasonic velocities of the same rock type, granite samples range from 3,118 to 5,380 m/s, and that the estimated weathering index can be highly biased if we use the fixed value of 5,000 m/s. We created a database (DB) by combining the measurement data and reported it. We also measured ultrasonic velocities by direct and indirect methods to quantify the calibration coefficient for each sampling site. We found that the calibration coefficients vary widely from site to site (1.31-1.76). Other factors, such as operator bias and temperature did not show any significant effect on errors in ultrasonic velocity measurements. Lastly, we applied our ultrasonic velocity DB and calibration coefficients to a stone cultural heritage, Bonghwang-ri Buddha statue. Our estimation of the weathering index was 0.3, 0.1 smaller than that by conventional method. The degree of deterioration was also different, "moderately weathered", while conventional method gave "highly weathered". Since other independent studies reported that the degree of deterioration of the Buddha statue was "moderately weathered", our estimation seems to be more accurate. Thus our method can help accurately evaluate the weathering index and the conservation planning for a stone cultural heritage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.399-404
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• 2004

This study was conducted to investigate the effect of monosodium glutamate (MSG) and fermentation methods (C-I; fermented for 5 days at 1$0^{\circ}C$ after 2$0^{\circ}C$ fermentation for 2 days, C-II; fermented for 7 days at 1$0^{\circ}C$, M-I; kimchi with MSG fermented for 5 days at 1$0^{\circ}C$ after 2$0^{\circ}C$ fermentation for 2 days, M-II; kimchi with MSG fermented for 7 days at 1$0^{\circ}C$ on fermentation and free amino acid content. Fermentation of M-I and M-II was slightly delayed compared to C-I and C-II. Total microbe of C-I and C-IIwere lower than those of M-I and M-II, and lactic acid bacteria of C-I and C-II were lower than those of M-I and M-II respectively. The major free amino acids were alanine, asparagine, homocystine and valine in C-I, especially, glutamic acid and ornithine were high in C-II. Homocystine, alanine, asparagine and valine in M-I, glutamic acid, alanine, hydroxyproline, asparagine, homocystine, ornithine and valine were the major free amino acid in M-II, respectively. The sour taste of M-I and M-II was lower than those of C-I and C-II, respectively, and the effect of delaying fermentation at 1$0^{\circ}C$ did not showed in the C-I and M-I. The crispy taste of the M-I and M-II was higher than those of C-I and C-II, which was the opposite results of sour taste. Palatable and overall taste of M-I and M-II were higher than those of C-I and C-II, respectively These results suggest that the MSG in kimchi affect not only increment of free amino acid content but also shelf-life and taste improvement, and continuous fermentation at 1$0^{\circ}C$ also enhance the content of free amino acid and shelf-life of kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.242-249
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• 2015

This study examined the antioxidant and antimicrobial activities of 70% ethanol extracts and water extracts of Allium hookeri root. We evaluated the effects of water extracts of A. hookeri root on storage of seasoned pork added with water extracts at $4^{\circ}C$ for 21 days in order to evaluate its potential as a functional food material. A. hookeri root water extracts displayed antioxidant activities (total polyphenol content and DPPH and ABTS radical scavenging activities) that were superior to those of 70% ethanol extracts. The 70% ethanol extracts and water extracts of A. hookeri root showed antimicrobial activities against food-borne Staphylococcus aureus bacteria that were about 1/400 times greater than that of vancomycin. Chemical composition analysis was conducted on pork seasoned with sauce containing 5%, 10%, and 15% water extracts. Moisture and crude ash contents significantly decreased as the amount of water extracts increased (P<0.05), and the highest crude protein content was in the 10% group. Acidity of seasoned pork increased proportionally in the early stages of storage, whereas it significantly decreased as the amount of water extracts increased after day 12 (P<0.05). Although the total number of bacteria in seasoned pork continuously increased during storage, growth of bacteria was significantly restricted as level of A. hookeri root water extracts increased (P<0.05). In the sensory evaluation, pork seasoned with 10% A. hookeri root water extracts showed the highest scores for taste, texture, and overall acceptance (P<0.05). In summary, A. hookeri water extracts display antioxidant and antimicrobial activities that can improve quality characteristics of seasoned pork and have potential as natural preservatives to restrict bacteria growth. Regarding the amount of extracts, 10% was determined to be the most appropriate level to minimize changes in seasoned pork during storage and improve sensory quality.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.149-156
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• 2016

Forest museums can be defined as facilities for the collection, exhibition, and education of the forest or forest related artifacts or data. This study was performed to measure the educational value of Gyeongnam state forest museum's forest and its environment. The tool used was the Contingent Valuation Methods (CVM) which is well known as a value estimation tool of environmental goods. The study for the value estimation is performed from April, 2014 to October of the same year through selection of the subject, decision of proposed price, and orientation of the survey staffs and total of 386 surveys were used in analysis. The value estimation tool used the DBDC logit model and the input parameters were number of visit (time), degree of environmental education (contri), the environment conservation effort of the respondent (execu), the education level of the respondent (edu), and income of the respondent (inc) and trimmed mean (WTPtruncated) was used. The estimated value of flora and environment education per each person per visit is 23,338 won. When applied to the average annual visitors deducted from 2010 to 2014, which is 430,000 per year, the environmental value that Gyeongnam state forest museum is providing to visitors each year is about 10 billion won. The result of this study is significant to propose the value of forest education and environment that the forest museum is offering to the visitors in the current currency. This is an evidence to directly determine the value of the forest museum and therefore proposing an opportunity change the recognition toward the forest and environment education.