• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.25-31
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• 1986

In order to contribute to the Korean tea-plant culture and tea industry by means of increasing the production of tea-plants, I have performed the tissue culture of the organs of the anther, leaf and stem. As for the culture-material, I have used the anther of tea (Thea sinensis) at the tetrad uninucleate microspore stage and used medium of modified Murashige and Skoog as the basal medium supplemented with the growth regulators of NAA and 2, 4-D, yeast, kinetin and others at various concentrations. As for the handling of material, I have followed the common methods of sterilization and microtoming and paraffine imbedding method and observed systematically periodic changes of the microspores in culture. I have divided the leaf, stem and root into segments and sterilized them and used the modified Murashige and Skoog as the basal medium and observed the differentiation of roots and callus and the results are as follows. 1. In case of anther, I have found 2n callus was found in 30 out of 100 segments in M2 medium. 2. The differentiation of roots appeared in 24.5% of total leaf segments cultured and in 50.5% of stem and in 43.9% of root. 3. When the differentiation of stem in different parts was observed, the most frequent differentiation was found in the second part of all the 4 parts. 4. The most frequent formation of callus was noticed from the anther-walls in case of anther culture and from the veins in case of leaf culture. It is concluded that the seedlings of tea-plant could be multiplied most by means of tissue culture of the second part of the tea-plant stem and reduction in the expenditures of tea-plant propagation was possible through tissue culture.

• Journal of radiological science and technology
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• v.11 no.1
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• pp.71-77
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• 1988

To improve the storage method for kimchi, optimal ripening kimchi was irradiated with doses of 1, 3, 5kGy Co-60gamma radiation, followed by the microbiological, physicochemical and senosory evaluations during storage at $5^{\circ}C$. 1. Total aerobic count increased in the beginning of storage and then decreased slowly as the number of total lactobacilli (anaerobe) increased. The above, total aerobic and lactobacilli were reduced by 1 to 3 log cycles with irradiation and at the 90th day after storage the number of total lactobacilli remained $1.30{\times}10^{8}$ per ml in 3 kGy irradiated group. Irradiation treatment at 3 kGy sterilized coliforms and molds contaminating the sample as the level of $2.0{\times}10^{4}$ per ml and $5.4{\times}10^{2}$ per ml respectively and no apparent growth was observed in both control and 1 kGy irradiated groups after 20 days of storage. The population of yeast, $3.5{\times}10^{3}$ per ml initially, increased steadily during kimchi storage and at 90 days of storage the number was shown to be $5.6{\times}10^{4}$ per ml and $6.5{\times}10^{2}$ per ml in control and 3 kGy irradiated groups, respectively. 2. In the physicochemical changes during kimchi storage, pH, acidity and volatile acid of non-irradiated control at the 45th day after storage were 4.0, 0.7% and 0.066%, while those of 3 kGy irradiated group were 4.2, 0.59 and 0.06% at the 90th day of storage, respectively. The reducing sugar content of all stored samples changed inversely total acidity content, indicating irradiation delayed the changes of them. The amount of ascorbic acid decreased gradually with the storage time and irradiation dose increase. Textural parameters of 3 kGy irradiated group were superior to those of other groups at the latter stage of storage. 3. Sensory evaluations showed that 3 kGy irradiation was the optimum dose level to extend the shelf-life of kimchi more than two months as compared to control.

• Radiation Oncology Journal
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• v.9 no.1
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• pp.123-130
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• 1991

A docking intraoperative electron beam applicator system, which is easily docking in the collimator for a linear accelerator after setting a sterilized transparent cone on the tumor bearing area in the operation room, has been designed to optimize dose distribution and to improve the efficiency of radiation treatment method with linear accelerator. This applicator system consisted of collimator holder with shielded metals and docking cone with transparent acrylic cylinder, A number of technical innovations have been used in the design of this system, this dooking cone gives a improving latral dose coverage at therapeutic volume. The position of $90\%$ isodose curve under suface of 8 cm diameter cone was extended $4\sim7$ mm at 12 MeV electron and the isodose measurements beneath the cone wall showed hot spots as great as $106\%$ for acrylic cone. The leakage radiation dose to tissues outside the cone wall was reduced as $3\sim5\%$ of output dose. A comprehensive set of dosimetric characteristics of the intraoperative radiation therapy applicator system is presented.

• Food Science and Preservation
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• v.11 no.3
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• pp.394-399
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• 2004

The effects of gamma irradiation to improve the hygienic quality and microbiological shelf stability of whole baked egg were investigated by comparison with autoclaving process. The contamination levels of coliform, total aerobic bacteria and fungal group in a fresh egg were 10$^{5}$ CFU/g, 10$^{2}$ CFU/g and 10$^{1}$ CFU/g, respectively. After baking process, total aerobic bacteria and fungi were not exceeded to 10$^{1}$ CFU/g. Also, coliform was not detected under the aseptic process. However, cell counts of the baked egg after packaging reached to 10$^{4}$ CFU/g of total aerobic bacteria, 10$^{1}$ CFU/g of coliform, and 10$^{2}$ CFU/g of fungi. Therefore, it was assumed that microbial contamination of baked and packaged egg was mainly originated from an environmental uptake during packaging process. Microbiological shelf stability of the non sterilized control was about a week. Whereas, the baked eggs irradiated at more than 5 kGy were stable over 12 weeks at ambient condition as like those being autoclaved. Analytical texture profIle was stable within 10 kGy, but it became hardened in the sample treated with autoclaving. About 67$\%$ of panelists identified a sensory difference between non-irradiated and 10 kGy-irradiated sample. The baked egg irradiated at 10 kGy and autoclaved had lower acceptability than the control or samples irradiated lower than 5 kGy. Therefore, it was considered that optimal irradiation dose for radiation sterilization of baked and packaged egg was 5 kGy. At that point, it was recommended that appropriate microbiological shelf-life was 12 weeks at ambient condition.

• Food Science and Preservation
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• v.12 no.6
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• pp.558-564
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• 2005

This study was carried out to investigate the cleaning effect of sesame leaf, the sterilization effect and physicochemical properties, treated with various electrolyzed water. Initial physicochemical properties could be kept more than 1 month in electrolyzed oxidizing water(EW-1) of diaphragm type and 15 days in electrolyzed water(EW-2 and EW-3) of non-diaphragm system, there was no significant difference by storage temperature. 4 kinds of microorganism (initial total counts, $10^7\~10^9$ CFU/mL) were sterilized within $0.5\~1$ minutes by electrolyzed water. In fresh sesame leaves, total viable cell count and coliform group in the treatment of electolyzed water were decreased to about $2\~3$ log scale comparing non-treated ones. Especially Bacillus cereus was not detected until 13th day when treated with EW-l. Decaying ratio of sesame leaf appears on day 6 of storage in the untreated but the treatments of electrolyzed water has no sign until day 10 of storage. Change in color difference(${\Delta}E$) during storage was observed the treatments of electrolyzed low-alkaline water(EW-2) and electrolyzed neutral water(EW-3) were very desirable at the level $1\~2$ after day 13 of storage comparative to the untreated Change of Chlorophyll content was biggest decreased to 6.8 $mg\%$ on the untreated and decreased least to 8.35 $mg\%$ on EW-3 treated group on 13th day from initial value of $9.0\~10.3\;mg\%$ The overall sensory evaluation appeared most acceptable in the treatments of EW-2 and EW-3.

• Korean journal of food and cookery science
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• v.29 no.4
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• pp.387-398
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• 2013

Seasoned soy sauce is one of the popular seasoning sauces added to the Korean traditional foods such as Bulgogi, Galbi. However, industrially processed sauces have poor sensory quality because of heating treatment for sterilization. The purpose of this study was to develop seasoned soy sauce having fresh taste and good quality by applying superheated steam (SHS) and high hydrostatic pressure (HHP) technologies. To maintenance the sauce qualities, food materials such as apple, onion, and garlic were pretreated with SHS (heater $100^{\circ}C$, steam $280^{\circ}C$, 30 s~1 min 30 s) before mixing with other ingredients. During storage of 7 days, color, pH, and browning potential of SHS treated samples (apple, onion and garlic) did not change and also polyphenol oxidase was inactivated (p<0.05). The seasoned soy sauce including SHS treated materials was sterilized by thermal process ($85^{\circ}C$, 30min) or non-thermal process, HHP (550 MPa, $5{\sim}10^{\circ}C$, 3 min). In SHS+HHP treated sauce, salinity, sugar contents, lightness, viscosity did not change (p<0.05), and total viable cell counts were detected below 4 log cycle at $5^{\circ}C$ for 30 days. E.coli and B.cereus are not determined in all samples. In sensory evaluation, Bulgogi prepared with SHS+HHP treated sauce was more acceptable than others.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.437-444
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• 2009

${\gamma}-Aminobutyric$ acid (GABA) producing lactic acid bacteria, Lactobacillus acidophilus RMK567 was cultivated in 50 L of sterilized MRS broth using a fermenter at $40^{\circ}C$ for 24 h. The cell number was increased to $10.04{\pm}0.13$ Log CFU/mL with a growth rate constant (k) of 0.454 generation/h and a generation time (g) of 2.303 h after a lapse of a lag phase (L) of 5.16 h. A total of 487 g of cell paste with 40.5% moisture was harvested with viable cell number of 12.48 Log CFU/g cell paste. The cell pastes after preparation with glycerol, glucose, and polydextrose as cryo-protectants were lyophilized under a vacuum of 84 m torr. A total of 408 g of freeze dried (FD) cell powders were mixed with a commercial strain of Streptococcus thermophilus to prepare of three types FD starter cultures with the viable cell numbers of 12.42 (FDA-GY), 12.60 (FDBGG) and 12.91 (FDC-GP) Log CFU/g. During preservation the FD cultures at -$18^{\circ}C$, the cell viability of the FD starter cultures were rapidly dropped to below 3.24% of the day of storage. No significant difference was found in the cell viabilities among three types of FD starters cultures, but significant difference (p<0.01) was found in storage periods. Yoghurts fermented through FD starter culture of L. acidophilus RMK567 were determined to contain $155.16{\pm}8.53$ ppm, $243.82{\pm}4.27$ ppm, and $198.64{\pm}23.46$ ppm of GABA, respectively. This study shows that GABA production activity of L. acidophilus RMK567 is not affected during the freeze drying process and would be available for commercial production of yoghurt containing high GABA content.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.12 no.1
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• pp.63-73
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• 2006

The first packaging of Korean market milk dates back to July 1937 when Seoul Dairy Co-operative (Kyung Seong Dairy Co-operative in those days) used 1 hob (180 ml) glass bottles with either paper caps or cork caps. During 1945-1972, 2 hob (360 ml) glass bottles were produced, and iron caps and egret-shaped plastic film replaced the previously used caps. When there were insufficient numbers of milk bottles, other glass bottles such as soda drink bottles and beer bottles were used instead. Seoul Dairy Co-operative was the only dairy company existing in Korea until Nam Yang Dairy Co. Ltd was founded in March 1964, followed by Hae Tae Dairy Co. Ltd(Tae Han Food Public Corporation in those days) in 1969 and Mae-il Dairy Co. Ltd (Korea Dairy Company in those days) in May 1971. As many other dairy companies along with the above-mentioned companies were established, a variety of dairy products were packaged and marketed. In 1971 Seoul Dairy Co-operative first used triangular-shaped polyethylene film wrappers, and in 1972 Nam Yang Diary was the first company importing sterilized Tetra pak for the packaging of milk. Since 1974 rectangular shaped polyethylene film wrappers and plastic bottles were used. In 1977 the gable top carton pack made of paper was first introduced by Seo Joo Industry Co. Ltd, and its market share increased rapidly with gradual increase in its volume, from 180ml to 200ml, to 250ml, to 500ml and finally to 1,000ml, causing change in the volume of milk consumption. And in Sep. 1987 Pasteur market milk Co. Ltd. first used round type high density polyethylene bottle(body) with low density polyethylene cap of 245g, 490g and 980g volumes respectively.

• Journal of Preventive Medicine and Public Health
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• v.21 no.1 s.23
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• pp.70-81
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• 1988

To measure the birth registration rate and the validity of birth registration data in rural area, all of the 4,014 married women under 49 years of age who had not been sterilized in Gunwee county of Kyungpook province were followed by Myun health workers for 2 years from April 1, 1985 to March 31, 1987 and 766 births were detected. All of the birth registration records of Myun offices were reviewed on September 30, 1987 and 944 births which occurred within the above mentioned period were found. Actual birth date obtained by follow-up study were compared with the birth date on registration card. Among 766 births detected by follow-up study,576 births(75.2%) which were reported within 6 months after birth were ascertained on the official registration records and 96 births(12.5%) were not found on the records although mother stated that the birth was registered. The registration rate within legal due date was 61.3% among 576 births detected by follow-up study and also ascertained on the official records. The registration rate within legal due date was lower in mothers under 20 years of age and above 35 years and in mothers who had only primary education. It was decreased as the birth order increased. The registration rate was higher in births occurred from October to March than births occurred from April to September. All of the births of 7 neonatal deaths were not reported. The registered birth date was consistent with the actual birth date in 78.0%. Birth date on record was earlier than the actual birth date in 6.8% and later in 15.3%. The consistency rate was lower in mothers above 35 years of age(54.5%), and in infants of 4th birth order and above(56.3%). The rate was increased as the maternal education level increased. The rate of boys was higher than that of girls. A higher percentage(17.4%) of infants born in March was registered with earlier date than the actual birth date and most of these registered birth dates were lunar calendar date. This might be related with the age for entering the primary school. The study findings revealed that the birth registration rate within legal due date and accuracy of report have been increased in recent years, but the infant mortality rate derived from the birth registration seems to be very inaccurate. It is suggested to let the medical personnel who delivered the baby report the birth by mail directly to the current address of parent while infants delivered at home without professional attendant may comply with the present registration system.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.37-43
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• 1992

Typhula incarnata grew over a temperature range of -5 to $20^{\circ}C$ with maximum growth at 10 to $15^{\circ}C$. Sclerotial production for T. incarnata was greatest at the higher temperature. Maximum mycelial growth of this pathogen occurred from pH 5.4 to 6.2. When carbon sources were added to a basal salt medium (Czapek's dox agar) at 5 g carbon sources/l, inulin, soluble starch, galactose, glucose, mannose, manitol, sucrose, maltose, cellobirose, trehalose, raffinose, and dextrin supported growth better than other carbon sources did. Of the twenty-three nitrogen sources tested, glycine, serine, ammonium sulfate, asparagine, asparatic acid, and ${\beta}-alanine$ were the most favorable for mycelial growth of T. incarnata. Cystine and cysteine were poor nitrogen sources. Ammonium salt of nitrogen sources supported growth better than nitrate salt of nitrogen sources. Potato dextrose agar, oat meal agar, and V-8 juice agar were the most favorable for mycelial growth and sclerotial formation. Appropriate addition of pepton to PDA decreased mycelial dry weight, but sucrose supported good growth of T. incarnata. Percent viable sclerotia of T. incarnate buried in bentgrass soil decreased from 2 months after treatment remarkably. Trichoderma riride and bacteria were isolated from non-germinated sclerotia. Live orchard grass leaf pieces within the soil were colonized by T. incarnata better than sterile and unsterile dead leaf pieces at $0^{\circ}C$. Saprophytic ability of T. incarnate on sterile leaf sheath occurred better at $0^{\circ}C$ than at $10^{\circ}C$. Saprophytic microflora consisting of Cladosporium sp., Fusarium sp., Mucor sp., Pythium sp., and unidentified fungi were the competitors for the sterilized and unsterilized substrate, but their colonization was not find on live leaf sheath buried in the soil at $0^{\circ}C$. In the effect of fungicides to Typhula snow mold disease of creeping bentgrass, mixture of polyoxin and thiram was the most effective, followed by iprodione, mixture of iprodione and oxine copper, thiophanate-methyl, myclobutanil, and tolclofos-methyl.