• Journal of Korean Society of Forest Science
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• v.23 no.1
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• pp.29-33
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• 1974

U-Reuk, a laureate musician in the days of King Jin-Heung, Silla Dynasty, built the Eui Rim Reservoir about 1,400 years ago. This was one of the oldest man-made reservoir. The embankment of the reservoir collapsed by the clumsy artificial drainage on August 19, 1972 when the heavy rainfall of 462 mm/day caused a dangerous overflow of the reservoir. The result of the study on the mystic ancient embankment techniques are as follows: 1. Sandy loam derived from the weathering of granite which is the most widely distributed rock type in the area, was used in the embankment. Large size logs (embankment core) of 30-50 cm in diameter were buried lengthwise along the embankment. 2. The six stocks of Pinus densiflora, 3 stocks of Quercus acutissima, 1 stock of Quercus variabilis and 1 stock of Popolus maximowiczii, altogether 11 stocks are identified. Forest types in the nearby area during the days of the reservoir construction seem to be includde a considerable number of Pinus densiflora, Quercus and Populus species. 3. The angle of repose of the earth materials is taken into account during the embankment. On top of the embankment double layers of clay (20-30 cm indepth) were spread and consolidated. Layer of litter of 20-40 cm in deep covered on the clay layer of the embankment completely, and another layer of clay was consolidated over the litter. Finally, a layer of stones of 10-30 cm in diameter and clay (yellow soil layer) toped the embankment. 4. At the lower part of the embankment clay layer was thicker and became thinner as it goes upwards. At every layer, soil was consolidated and burned. When embankment was completed, it was covered evenly with heavy clay, and finally it was topped with general soil. 5. The heavy clay layer on the inner slope of the embankment showed gray phenomena and litter remained raw humus layer. The clay layer functioned as rubber in the water, and raw humus layer prevented water from seepages. Thus, the embankment was solidly built in this way. 6. The ancient embankment techniques used soils conveyed from nearby area taking the angle of repose into account. Once embankment was completed, clay and litter layers were added to have a plasticity and to withstand the water pressure. 7. It is an excellent technique that the reservoir was constructed with least labor for maximum effects while the recent embankment techniques requires a large amount of labor.

• Journal of Ginseng Research
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• v.26 no.4
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• pp.219-225
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• 2002

Study was performed to know the effects of Panax ginseng C.A. Meyer hairy root due to $^{60}$ Co ${\gamma}$-ray irradiation. We irradiated the hairy roots under the various $^{60}$ Co ${\gamma}$-ray; 0.5~4 Krad. The growth of hairy roots is inhibited over 3 Krad treatment. The lateral roots are used as a cell line after removing the apical meristem of hairy roots irradiated below 2 Krad. We selected 206 hairy root cell lines having various different growth rates and forms, and incubated in the 1/2 Murashige & Skoog(MS) medium in the absence of hormone. We selected 10 out of 206 showing superior growth. Among those, ${\gamma}$-GHR 70 and ${\gamma}$-GHR 94 showed higher growth; 34.5, 44.7%, respectively. We observed shapable, sizable characteristics according to the width of the primary roots, the process formation of the lateral roots, and the growth of lateral roots. The discriminable cell line showed that primary root is thinner, and has a vigorous growth. 8 out of 10 had much more contents than control in the aspect of the ginsenoside. ${\gamma}$-GHR 59 and ${\gamma}$-GHR 94 showed higher contents; 19, 16.9%, respectively. Therefore, we selected ${\gamma}$-GHR 70, ${\gamma}$-GHR 94 as a superior cell line in the aspect of ginsenoside contents, and growth among those irradiated by ${\gamma}$-ray. According to content of ginsenoside, Rb$_2$ effective in anticancer has 7.5% of ${\gamma}$-GHR 59. Rc, also effective in anticancer showed 16.2% content increasement of ${\gamma}$-GHR 69. It is thought that those lines will be effective in manufacturing ginsenoside. Gene analysis (VNTRP) related to the mutation is in progress.

• Korean Journal of Plant Resources
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• v.33 no.2
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• pp.80-85
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• 2020

A new Gomchwi cultivar 'Soomany' was derived from a cross between Gomchwi (Ligularia fischeri (Ledeb.) Turcz.) and Handaeri-gomchwi (Ligularia fischeri var. spiciformis Nakai). The investigation and selection of growth and yield characteristics were conducted from 2007 to 2015 in field and greenhouse of Highland Agriculture Research Institute, National Institute of Crop Science, Rural Development Administration, in Korea. On a newly developed cultivar 'Soomany', color of petiole ear is light green, petiole trichome is existent, trichome and light on the back of the leaves don't exist, and density of leaf vein is degree 4. Plant height, leaf length, leaf width and petiole length are 77.1, 22.3, 21.5 and 57.2 cm, respectively in the growth characteristics of the 2_nd year. Plant size was also higher than that of 'Sammany' generally. Bolting date was on August 15. Flowering date was on September 19, about 9 days later than 'Sammany'. 'Soomany' and 'Sammany' had 149 and 133 leaves per plant, respectively. Total yield of 'Soomany' (1,623 g/plant) made a very good comparison with that of 'Sammany' (1,385 g/plant). 'Soomany' showed harder leaves (25.8 ㎏/㎠) than 'Sammany' (20.8 ㎏/㎠), whereas 'Soomany' had thinner leaves (0.53 mm) than 'Sammany' (0.62 mm). 'Soomany' variety has shown strong resistance to powdery mildew disease compared to 'Sammany'. In May 2019, the right of variety protection of 'Soomany' was registered as a new Gomchwi variety (Register No. 192).

• Korean Journal of Veterinary Service
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• v.23 no.3
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• pp.235-245
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• 2000

This study was peformed to elucidate the effects of antler, red ginseng, safflower seed, ipriflavone and estrogen on ovariectomized rats. The rats were fed with Ca and P deficient diet for five weeks to induce osteoporosis. After this period, these animals were fed with normal for and treated every other day with antler(600mg/kg, PO), red ginseng(200mg/kg, PO), safflower(200mg/kg, PO), ipriflavone(80mg/kg, PO) and estrogene(400$\mu\textrm{g}$/kg, IM) for S weeks. During the treatment, the rats were examined for body, organ, femur and femur ash weights. And electron-microscopical examinations were also performed on femora. The results are summarized as follows : 1. The body weights of the antler, red ginseng, safflower, ipriflavone and estrogen-treated groups after five weeks of treatment, were 303.0$\pm$3.0g, 273.3$\pm$4.4g, 288.3$\pm$5.1g, 300.5$\pm$5.2g, 320.5$\pm$4.2g, respectively. They, except the red ginseng-treated group, were significantly higher than 278.4$\pm$2.7g of normal control group(P<0.05). And the body weight of non-treatment group was 29it.2$\pm$5.5g which was higher than that of control group, too. 2. The weights of left femur after five weeks of treatment were showed 0.83$\pm$0.2g by antler, 0.89$\pm$0.2g by red ginseng, 0.87$\pm$0.2g by safflower 0.83$\pm$0.1g by ipriflavone and 0.78$\pm$0.1g by estrogen-treated group. They were a little lower than 0.97$\pm$0.1g of normal control group. Non-treatment group showed 0.83$\pm$0.1g which was lower than that of control group but not significant. 3. The weights of ashed left femora after five weeks of treatment were showed 0.36$\pm$0.01g by antler, 0.40$\pm$0.01g by red ginseng, 0.41$\pm$0.01g by safflower, 0.36$\pm$0.01g by ipriflavone and 0.35$\pm$0.01g by estrogen-treated group. Those results were significantly lower than 0.43$\pm$0.01g of normal control group. And non-treatment group showed 0.29$\pm$0.01g of femoral ash which was significantly lower than that showed by control group(p<0.05). 4. The femoral Ca contents of the antler, red ginseng, safflower, ipriflavone and estrogen-treated rats were 19.6$\pm$0.7%, 17.8$\pm$1.1%, 18.8$\pm$0.9%, 18.0$\pm$1.1%, 15.3$\pm$1.1%, respectively, after five weeks of treatment. The femoral Ca contents of antler and safflower-treated groups were higher than that of control group which showed 18.2$\pm$0.9% of Ca The non-treatment group, showing 15.3$\pm$0.7%, had significantly lower content of Ca than normal group(p<0.05). 5. The weights of liver, spleen, and kidney in the osteoporosis-induced rats during the treatment with antler, red ginseng, safflower, jpriflavone and estrogen showed not significant changes. 6. The connections among the trabeculae of control group were maintained well, showing no bone loss. However, the connections among the trabeculae of non-treatment group were thinner than those of control group and were almost disconnected and the lacunae were found to be broadened. Antler and safflower-treated group showed only slight changes. The recovery rates were prominent in antler, safflower, estrogen-treated groups but they were insignificant in red ginseng and ipriflavone-treated groups.

• The korean journal of orthodontics
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• v.41 no.5
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• pp.312-323
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• 2011

Objective: This study compared the bone thickness of the palate between lateral cephalogram and 3D model measurements. Methods: The subjects consisted of 30 adults (15 men,15 women) with a normal skeletal pattern and occlusion. The CT images were transformed to a 3D model, and were compared with the cephalometric image. Descriptive statistics for each variable were calculated. Results: In the 3D CT model, the mid-palatal area was the thickest part. It became thinner as the palate tapered laterally. In the male group, the thinnest portion was positioned 6 mm away from the mid-palate, while in the female group the thinnest portion was 8mm away from the mid-palate. Correlation analysis between the lateral cephalometric and 3D CT model revealed a significant correlation except in the mid palatal area and the area 2 mm lateral to the mid-palate in men, whereas there was a significant relationship in every area in the women. In both men and women, the highest correlation appeared in the area 8 mm lateral to the mid palate. Conclusions: Using regression analysis, an actual prediction of the bone thickness between the measured bone thickness of the lateral cephalometric radiograph and 3D model was made. This will provide useful information for mini-implant length selection when inserting into the palate.

• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.1-7
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• 2005

Radiation absorption parameters of carbon fiber panel were measured in comparison to acrylic panel. $30{\times}30cm$ sized 2mm thick carbon fiber panel and identical sized 6mm thick acrylic panel were placed in tray holder position and 0cm, 5cm, 10cm from surface of phantom. Radiation field size was $10{\times}10cm$. 50MU of 4MV photon was irradiated to the phantom with dose rate of 300MU/min. Source-to-phantom distance was 120cm. Radiation dose was measured with 0.6cc Farmer-type ionization chamber with 1cm build-up. Measurement was repeated thrice and normalization was done to the dose of the open field. Radiation transmission rate of carbon fiber panel is approximately 1% lower than acrylic panel of equivalent thickness. However, considering the strength of the material, transmission rate is higher for carbon fiber panel. Although carbon fiber panel increases the radiation dose when attached to the surface for about 2%, it normalizes the radiation dose to 97-99% of irradiated dose which could have been lowered to as much as 5-7.5% with acrylic panel. As carbon fiber panel is stronger than acrylic panel, radiation fixation device could be made thinner and thus lighter and furthermore, with increased radiation transmission. This in turn makes carbon fiber more ideal material for radiation fixation device over conventionally used acrylic.

• Journal of Aquaculture
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• v.13 no.2
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• pp.169-174
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• 2000

Reproductive cycle of U. unicinctus was studied from September 1998 to August 1999, using gonadosomatic index (CSI) as an indicator. In November, the CSI values were maximum for male (6.2) and female (7.0), respectively; the values were lowest for them (1.0 and 0.5) during the successive february. Subsequently, they rapidly increased and attained peak by March-April. The values decreased again in both sexes and remained unchanged until August. The index increased in October to attain the peak by November. The CSI values clearly indicated that there are two spawning events in a year, namely the first one during April-May and the second one in December. Reproductive cycle was classified into the following successive stages: in female, multipication (January~February, June ~Setember), maturation (March~April, November), spent (May and December), degeneration and resting (June and January), and in male, multiplication January ~ february, June ~September), maturation (March~April, October~November), spent (May and December) and degeneration and resting (January and June). Histological observations revealed that oocytes in the ovary matured simultaneously in November and March. At the same time, the envelopes of matured testis became thinner than those in the early stage.

• Restorative Dentistry and Endodontics
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• v.29 no.2
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• pp.177-184
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• 2004

Objectives : This study investigated the hypothesis that increasing light-curing time would leave the oxygen-inhibited layer (OIL) of the adhesive thinner, and in turn, result in lower shear bond strength (SBS) than those obtained by the routine curing procedures. Methods：120 human extracted posterior teeth were randomly divided into three groups for bonding with three adhesives：All Bond 2/sup (R)/, One Step/sup (R)/, and Adper Prompt/sup (R)/. They were subsequently divided into four subgourps with different light-curing time (10, 20, 30 and 60s). The assigned adhesives were applied on superficial occlusal dentin according to the manufacturer's instructions and cured with one of the four curing times. Composite resin cylinder, 2.35㎜ in diameter, were built on the cured adhesive and light-cured for 40s. SBS were measured after 24h from the bonding using a universal testing machine (crosshead speed 1.0 ㎜/min). The relative thickness of the OIL and the degree of conversion (DC) were determined from the adhesive on a slide glass using FT-NIR in an absorbance mode. Data were analysed with One-way ANOVA and Duncan's multiple test (p〈0.05), Results：With increasing cure time, although there were no significant difference in th SBS of One-step and Adper Prompt (p〉0.05), those of All Bond 2 decreased significantly (p〈0.05). The relative thicknesses of the OIL on each adhesive were not affected by the cure time (p〉0.05). Although the DC of All-Bond 2 were statistically not different with increasing cure time (p〉0.05), those of One-Step and Adper Prompt showed an increasing trends with increasing cure time (p〈0.05). Conclusions：Increasing light-curing time did not affect on the relative thickness of the OIL of the adhesives, and in turn, on the SBS to dentin.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.34-45
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• 2003

Silk was treated with calcium hydroxide for degumming at different treatment times, temperatures and Ca(OH)$_2$ concentration to optimize degumming conditions in this thesis. After degumming, soluble and insoluble sericin were seperated and then the soluble sericin was characterized by measuring the average degree of polymerization (D.P.), lysinoalanine (LAL) content, DSC, and by amino acid analysis. And degummed silk fibroin was characterized by measuring tenacity and SEM. Degumming loss was increased by increasing the treatment time and temperature until about 30 minutes. After then, a slight difference was found along with treatment times at the Ca(OH)$_2$ concentrations of 0.07% and 0.1% solutions. After degumming, insoluble sericin ratio on degumming solution was increased by increasing treatment temperature at Ca(OH)$_2$ 0.04% solution. At the concentration Ca(OH)$_2$ of 0.07%, a soluble ratio was almost 100% regardless of treatment time and temperature. At the beginning of treatment, insoluble ratio was high at Ca(OH)$_2$ 0.1% solution but it was decreased by increasing treatment time. At the Ca(OH)$_2$ concentration of 0.04%, D.P. of soluble sericin was maintained as a constant value of 10 at 100$^{\circ}C$ although treatment time was increased. However, at 80$^{\circ}C$ and 90$^{\circ}C$, it was hard to prepare a soluble sericin having a constant D.P. by increasing treatment time. At the Ca(OH)$_2$ concentration of 0.07%, D.P. was almost 10 irrespective of treatment temperature and time. Soluble sericins with high D.P. of 20∼30 were obtained at 0.1% and 100$^{\circ}C$. LAL was not detected in soluble sericin. As the results of amino acid analysis, it showed that Ca(OH)$_2$ degumming reduced the contents of hydroxy amino acids like Ser., Thr. and Tyr. In DSC analysis of soluble sericin, endothermic peak by thermal deformation and pyrolysis showed at 189$^{\circ}C$ and at 299$^{\circ}C$, respectively. The tenacities of degummed silk were 15∼30% lower than that of raw silk. And it was decreased with increasing treatment time. From the morphological study, the thickness of degummed silk fibroin became thinner by increasing degumming loss. The roughness of a silk fibroin surface was appeared as treatment concentration was increased.

• Radiation Oncology Journal
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• v.23 no.2
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• pp.123-130
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• 2005

Purpose: We wanted to improve the setup reproducibility of breast cancer patients when utilizing a commercially available breast board for radiation therapy. The breast board was modified by using a new head rest and 2 types of board fixation devices. Materials and Methods: A conventional head/neck rest was modified to be positioned in various slots of the breast board, and it was fabricated 1 cm thinner to provide more comfort to a patient when the patient's neck was rotated. This rest improves the uncertainty of the daily setup. Also, the sagging problems at the left and right sides became negligible with the two types of board fixation devices: (1) the stair type, and (2) the arm type. The first device consists of an upper/lower holder with 4 stair-types of grooves and 4 rectangular Inserts. In order to cover the whole range of vertical setup of the breast board, 4 rectangular inserts were needed, and each covered 10 steps. The arm-type fixation device was also fabricated and attached to the breast board, It had two aluminum bars that were fixed by utilizing a lock-type of screw. These devises were evaluated with two volunteers in order to prove the effectiveness of the improved setup accuracy. Results; The developed cranio-caudal fixation device demonstrated that it could reduce the cranio-caudal error by nearly $55\%$ compared to the old device. As for left-and-right inclination, the stair-type and arm-type fixation devices can reduce the relative inclination by nearly $80\%$ and $90\%$, respectively, compared to the breast board without the fixation device. Conclusion: It was verified that the developed devices were effective for positioning the patients and for avoiding inclination of the breast board.