• The Korean Journal of Zoology
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• v.14 no.4
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• pp.199-204
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• 1971

The effect of 400 R total-body X-irradiation on the rate of deoxycytidine-2-$^14 C$(CdR-2-$^14 C$) into DNA and on the degradation of DNA has been studied in the liver, spleen and thymus of the rat. The postirradiation period can be divided into a radiation reaction period followed by a regeneration period. During the period of radiation reaction, which consists of days 1-2, markdely decreased CdR-2-$^14 C$ incorporation into DNA of each organ is observed. Rate of incorporation of labeled precursor in the thymus shows the most profound decrease, whereas those in the liver and spleen show similar decrease when expressed as percent of normal. The change in the amount of DNA as percent of normal exhibits a similar pattern in all organs, but the rate of decrease is larger in the spleen and thymus compared to that in the liver. The period of regeneration as judged by the incorporation experiment appears day 4 to 5, which consists of the second phase of the regeneration period. The second phase is highlighted by a markedly increased rate of CdR-2-$^14 C$ incorporation and by a slow and continued increase in the amount of DNA in all organs. The regeneration occurs faster in the liver and spleen than in the thymus which is the most radiosensitive of the all. The findings of the present experiments are strongly suggestive of the fact that the radiation-induced loss of spleen and thymus DNA as well as the radiation-caused inhibition in the CdR incorporation into DNA of the thymus are the important factors in the elevated levels of CdR in the urine and plasma.

• Korean Journal of Medicinal Crop Science
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• v.16 no.4
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• pp.238-241
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• 2008

Astragalus membranaceus have used as a medicinal herb and food in Korea. It is limited its harvest by diseases, pests and climate, therefore the main objective of Astragalus membranaceus breeding is the development of varities with the resistance for them. We used mutation breeding to obtain the genetic resources with the resistance for them. Pocheon, the local variety of Astragalus membranaceus, was treated with different levels Y-ray of $100{\sim}600$ Gy. There were investigated the sensitivity on germination and survival rate, plant height and the other characters. Germination rate from 4th day after sowing was significantly decreased above the 300 Gy as compared to the control. Compared to control, the decrements of survival rate were 32, 43, 63, 72, 84 and 89% for 100, 200, 300, 400, 500 and 600 Gy, respectively. The sensitive characters to Y-ray were plant height, number of branches per plant and survival rate, and the insensitive characters were number of leaves, length of leaf, and width of leaf. Plant height, number of branches per plant and survival rate seemed to be appropriate characters to decide the radiosensitivity, and radiation doses of $200{\sim}300$ Gy ($LD_{50}$) were recommend for mutation breeding.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.441-445
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• 2009

Recent research has revealed that hydrolyzed collagen peptides have beneficial effects in various diseases such as osteoarthritis and human rheumatoid arthritis and also play a protective role in skin by improving the activity of antioxidants. In this study, we investigated the effects of a novel mixture (AP-CPM01) containing collagen peptides and elastin peptides on photoaged hairless mice skin both in vivo and in vitro. To evaluate the effects of AP-CPM01 on UVBinduced skin wrinkle formation in vivo, the hairless mice were exposed to UVB irradiation and orally administered the AP-CPM01 at 333 mg/kg per day for 10 weeks. The effects on skin appearance and epidermal thickness were measured using bioengineering and histochemical methods. In addition, the influence of AP-CPM01 on collagen metabolism in human skin fibroblasts was also investigated. The skin of mice in the AP-CPM01 treated group had better appearance and less wrinkling than that of mice in the control group. In the human fibroblast cells, the amount of de novo procollagen synthesis was increased after AP-CPM01 treatment, reflecting that AP-CPM01 can induce de novo procollagen synthesis and reduce UVB-induced skin wrinkle formation. These results suggest that AP-CPM01 is a potent candidate for antiphotoaging functions.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.169-175
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• 2003

For safe and easy disposal of prochloraz wastewaters after used as rice seed disinfectant in Korean farms, this experiment was carried out. By addition of several agricultural materials commonly utilizing in farmers, removal effect of prochloraz from waste solution was also investigated. When rice seeds after soaking in diluted prochloraz solution were rinsed with water several times, prochloraz was removed $9.2\sim10.6%$ at the first rinse and less than 3 % at the fourth rinse. A half life of prochloraz was $4\sim5$ days in aqueous system. Hydrolysis of prochloraz was more rapidly in alkali solution than neutral and acidic one at $25^{\circ}C$ and $35^{\circ}C$. By the irradiation under $5530J/cm^2$ using xenone lamp, prochloraz was photo-degraded to 87.7% in aqueous system. The removal efficiency of prochloraz by addition of several agricultural materials were as follows: 93.6% by lime, 90.7% by composed pig manure, 89.4% by activated charcoal, 78.0% by straw ash, 70.3% by sandy loam soil, 47.0% by zeolite and 24.1 % by rice straw. When prochloraz solution was sprayed on the field soil, it was dissipated upto 90% within 35 days.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.99-105
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• 1986

Optimal balance between control probability and risk of complication is emphasized even in present time, Although certain incidence of intestinal injury is accepted as an inevitable consequence after abdominopelvic irradiation, these complications still remain as problems. 60 mice were irradiated with 250 kVp orthovoltage x-ray machine and $200rad{\times}5/wk$ regimen. Histpathologic findings of colorectum and the relationship with occult blood test were analyzed and possible tolerable dose which would be safe from permanent complication was also estimated. Followings are the results: Mild mucosal and submucosal edema were observed in 1,000 rad irradiated group. Congestion of small vessels was prominent in 2,000 rad irradiated group and infiltration of inflammatory cells was observed in 3,000 rad irradiated group. Denuded mucosa was observed in 3,000 rad irradiated group. Occult blood test is not a proper indicator for rectal denuding or rectal ulcer, but our results suggest the possibility of using this as a relative scale of intestinal damage. Mitotic figures of crypt cells were observed even in 5,000 rad irradiated group, these suggest that the repair capacity of crypt cells are still functioning.

• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.100-105
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• 1972

This experiment was conducted to investigate the combined effects of radiation and antiseptics on the keeping qualities of pork sausage, which was treated with potassium sorbate and AF-2(2-(-2-furyl)-3-(5-nitro-2-furyl)-acrylamide), and then followed by gamma radiation of 0.25, 0.5, and 0.75 Mrad. Amounts of treated antiseptics were a quarter, half, and full levels of their maximum permissible concentration. Irradiated and unirradiated sausages were stored for 50 days at $5^{\circ}C\;and\;25^{\circ}C$, and their changes in rancidity, volatile basic nitrogen, bacterial counts, pH, and sensory analysis were examined during the storage period. The results obtained are as follows: 1) Preservative effects of antiseptics were manifested at cold storage; antiseptics treatment of a quarter-level and unirradiation following low-temperature storage showed the same good keeping qualities as the combined treatment of full-level antiseptics and radiation of 0.25 Mrad following high-temperature storage. 2) There did not appear to recognize irradiation-odor, while color and odor were deteriorated intensively by storage temperature. Sausage irradiated with 0.75 Mrad has shown slightly noticeable off-odor at the end of storage at $25^{\circ}C$. 3) The most suitable radiation dose was considered to be 0.5 Mrad, which could extend the storage life about $2{\sim}3$ times longer than untreated.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.100-105
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• 1987

To study the relative effectiveness of the antioxidants (BHA, BHT) and the transparent cellophane films (colorless, blue and red) on rancidity development of the sesame oils treated with sunlight - irradiation condition, this experiment was carried out. The results obtained as follows ; 1. The retarding effect of the antioxidants on POV, COV and TBA development was more effective than control, and Bill was more effective than BHA. 2. The transparent cellophane films were more effective than antioxidants, and red was more effective than blue transparent cellophane film. 3. During the storage of the sesame oils which were covered with colorless, blue and red thansparent cellophane film respectively, the contents of linoleic acid in sesame oil were decreased, while oleic acid were increased.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.4
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• pp.351-359
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• 2015

Acute and chronic ultraviolet (UV) irradiation triggers severe skin photoaging processes, which directly disrupt the normal three-dimensional integrity of skin. UV light stimulates the expression of matrix metalloproteinases (MMPs) which degrade constituents of extracellular matrix (ECM) proteins. These MMPs reduce collagen synthesis and decrease skin elasticity and integrity, resulting in wrinkle formation. In this study, we identified Rosa multiflora hip extract (RME) as an effective anti-photoaging ingredient. First, cell proliferation activity of RME was verified using Hs68 human dermal fibroblast cell line. RME downregulated MMPs expression through the inhibition of activator protein (AP)-1. In addition, type I and IV collagen expressions were increased with RME treatment and UVB-induced inflammatory responses were also reduced after RME treatment. In conclusion, R. multiflora hip extract may effectively improve UVB-induced skin aging and wrinkle formation which may provide as an anti-aging, anti-wrinkle, and anti-inflammation ingredient in cosmetic industry.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.107-112
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• 2011

In this study, photocatalytic degradation and mineralization of bisphenol A (BPA), which has been listed as one of endocrine disruptors, were carried out in the CPC system using $Tio_2$ slurry and UVA irradiation. The degradation efficiency has been investigated under the controlled parameters including initial concentration (5, 10, 20 mg/L), dosage of $Tio_2$ (0.1, 0.5, 1.0 g/L), UVA power (0, 80, 120 W) and temperature (0, 20, 30). At 10mg/L of initial concentration, BPA was degraded above 80% after 10min, BPA were degraded 97% and 49% at 20 mg/L and 30 mg/L, respectively. At $Tio_2$ dosage was 0.1 and 0.5 g/L, the degradations of BPA showed similar trend and were about 70% after 1 hr, and the degradation of BPA was above 80% after 30 min at 1 g/L of $Tio_2$ dosage. The increase of degradation seem to be due to the increase in the total surface area, namely number of active sites, available for the photocatalytic reaction as the dosage of photocatalyst increased. When the UVA power was 120 W, BPA was degraded rapidly above 60% after 10min of reaction time. To investigate the effect of temperature, carried out experiment controlled temperature, there were no significant differences depending on the temperature. After 1hr, the degradation of BPA were 46%, 67%, and 69% at 10, 20 and $30^{\circ}C$.

• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.715-721
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• 2021

In radiation brachytherapy, the wrong source location may cause excessive dose to normal tissue. Therefore, research on digital dosimeters is being made to replace the analog detection method. Therefore, in this study, a lead (II) oxide (PbO) dosimeter applied with a passive layer (PL) was fabricated as a basic study to improve the dosimeter performance. Afterwards, reproducibility, linearity, and distance dependence were evaluated to analyze the performance of the Ir-192 source under irradiation conditions. The reproducibility of the PL-PbO dosimeter was 0.40%, which satisfies the evaluation criteria of 1.5%, and showed improved results compared to the PbO dosimeter. Linear function R2 showed excellent results as 0.9995, and slope analysis through regression analysis of the linear function was excellent in PL-PbO. The distance dependence of the PL-PbO dosimeter was +0.599 higher than that of PbO when the slope obtained through regression analysis of the power function was compared with the inverse square value. This study presents the effects and measurement variables according to the measurement configuration of the solid-state dosimeter, and can be used in various radiation detection fields.