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Prenatal Deaths and External Malformations Caused by X-Irradiation during the Preimplantation Period of ddy Mice (임신 ddy Mice에서 착상전기 방사선 조사에 따른 산전 사망 및 외부 기형 발현)

  • Ro, Hee-Jeong;Choi, Ihl-Bhong;Gu, Yeun-Wh
    • Radiation Oncology Journal
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    • v.16 no.3
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    • pp.233-243
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    • 1998
  • Purpose : To evaluate the effects of X-irradiation on prenatal deaths, i.e., preimplantation deaths, embryonic deaths and fetal deaths, and on external malformations in precompacted preimplantation ddy mice Materials and Methods : Pregnant mice (n=85) obtained by limiting the mating time to from 6 to 9 A.M., were segregated into 11 groups. The first five groups (n=26) were irradiated with X-ray doses of 0.1 0.5, 0.75, 1.5, and 3 Gy, respectively, at 24 h post conception (p.c.) of the preimplantation Period. The second five (n=27) groups were irradiated at the same X-ray doses, respectively, but at 48 h p.c. of the preimplantation period. The last group (n=32) was the control group. The uterine contents were examined on the 18th day of gestation for prenatal deaths and external malformations. Results : 1) A statistically significant increase in preimplantation deaths with increasing dose was observed in the experimental groups irradiated at 24 h p.c. and in the groups irradiated at 48 h p.c., as compared to the control group. The threshold dose was close to 0.05 Gy and 0.075 Gy for the irradiations at 24 h p.c. and 48 h p.c. respectively. 2) A statistically significant increase in embryonic deaths with increasing dose was observed in all irradiation groups, except the group irradiated with a dose of 0.1 Gy at 48 h p.c.. 3) No fetal deaths were found in any experimental group. 4) In the experimental groups irradiated at 24 h p.c. anomalies increased with statistical significance, as compared with the control group : 2 exencephalies, 2 open eyelids, 3 anophthalmias, 2 cleft Palates, 2 gastroschisis, 1 abdominal wall defect. 1 leg defect, and 2 short tail anomalies: the threshold dose for external malformations was close to 0.2 Gy at 24 h p.c.. In the groups irradiated at 48 h p.c., 1 open eyelid and 2 short tail anomalies were observed, but there was no statistical significance in those malformations. Conclusion : The results of this study reveal that X-irradiation of precompacted preimplantation ddy mice causes not only preimplantation deaths and embryonic deaths but also external malformations. In addition, external malformations were observed in our experiments at diagnostic doses, including 0.1 and 0.5 Gy. For this reason, we recommend that irradiation should be avoided during the preimplantation period by applying Rugh's 10-day rule.

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A Study on the Difference of Strategies for Conflict Resolution between Rural Residents and Urban-to-Rural Migrants (게임이론에 근거한 농촌원주민과 귀농·귀촌인 간 갈등해결 전략차이 연구)

  • Kim, Tae-kyun;Park, Sang-hyeok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.2
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    • pp.151-163
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    • 2019
  • In recent years, as the population of ear and aged villages has increased, the problem of conflict between rural residents and urban-to-rural migrants has been widespread. For successful rural community, such conflict resolution is more important than anything else. However, if we look at previous studies. It is true that there are many studies that focus on people who are not rural residents or urban-to-rural migrants. This study was conducted to find out the difference of strategies for conflict resolution between rural residents and urban-to-rural migrants. This study derives the factors of conflict based on the contents of previous studies, To see the difference, five strategies were used from the response strategies that were used in the 'Computer Prisoner's Dilemma Contest' held by Axelrod (2009). I would like to know what kind of strategies of rural residents and urban-to-rural migrants. All analyzes were done using SPSS 22.0 for Windows, and the results of each conflict resolution analysis showed that the indigenous conflicts were low All. Among the causes of conflict, the highest level of conflict was caused by the 'rural residents who did not understand urban culture'. The strategy is the most used, followed by tit for tat Strategy, and all-c strategy, in that order. However, It is not uncommon for employers to use a work-type strategy, and it can be seen that the strategy changes depending on the cause. As can be seen from the above results, The conflict resolution strategies are almost similar strategies. It can be seen that conflict resolution strategy is used differently according to personality. The purpose of this study is to investigate the differences in conflicts in the rural areas. In particular, it is meaningful to examine the choice of solution strategies based on game theory through reviewing prior research and eliciting actual conflict factors in the field. Successful rural settlement can be achieved not through stakeholder competition but through mutual cooperation by gaining cooperation to the other side. Mutual cooperation is more profitable than betrayal in various conflict situations. The secret to maintaining and communicating smoothly is not to use the other person to fill his or her selfish interests, but to reject it for profit, but to draw cooperation from the other party.

A Study on the Acute Toxicity of AF-2 (AF-2의 독성(毒性)에 관(關)한 연구(硏究)(급성중독(急性中毒)))

  • Park, Young-Ran;Lee, Yul;Sung, Nak-Eung
    • Korean Journal of Food Science and Technology
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    • v.8 no.1
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    • pp.53-60
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    • 1976
  • This study was undertaken to investigate the toxic effect of AF-2, 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide, in the diet of rats (Splague Dowley) for 4 weeks. Comparisons were made of weight gains, organ weights and the cholesterol, phospholipid and triglyceride content of the blood serum and liver tissue. Rats were divided into three groups, a control group which was fed on a standard diet and two groups were fed with 0.04% (group I) and 0.2% (group II) of AF-2. Male rats weighing 370-410 g, female rats weighing 240-250 g were used in this experiment and each group was composed of 24 Albino rats. The results were as follows. 1. Comparisons of weight gains, control and experimental groups did not show significant differences. 2. An examination of organ weights, liver weights of experimental groups showed higher than that of the control group. 3. In the lipid content of blood serum, phospholipid contents of experimental groups were lower than that of the control, while cholesterol and triglyceride content of experimental groups were higher than that of the control. 4. In the lipid content of liver tissue, phospholipid and triglyceride content of experimental groups did not show considerable changes, but cholesterol content was increased in proportion to AF-2 content. From these results, the authors could observe the significant changes in weight gains of liver and cholesterol content after feeding. It is concluded that the toxic effect of group II showed higher than that of group I and AF-2 had a toxic effect on rat liver to a certain extent.

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Antioxidant activities of blueberry hot water extracts with different extraction condition (추출조건에 따른 블루베리 열수추출물의 항산화 활성 비교)

  • Ko, Gyeong-A;Son, Moa;Kang, Hye Rim;Lim, Ji Hee;Im, Geun Hyung;Kim, Somi
    • Food Science and Preservation
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    • v.22 no.3
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    • pp.428-436
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    • 2015
  • Five extraction conditions (AE, autoclave extraction; OE, oven extraction; HWSE, hot water and sonication extraction; HWASE, hot water acidified with 0.5% (v/v) acetic acid and sonication extraction; and BE, boiling extraction) were examined to compare the effects of different hot water extraction methods on the antioxidant properties of blueberries. The extraction yields of the AE, OE, HWSE, HWASE, and BE were 7.94%, 8.35%, 8.55% 9.15%, and 8.50%, respectively. The polyphenol and flavonoid contents of AE were 3.47 mg GAE/g and 1.59 mg RE/g, respectively, which were highest centents among others. Those of OE were ranked second to the highest. The total anthocyanin content of HWSE (5.29 mg/g) was significantly higher than that of others whereas that of AE showed the lowest content (0.96 mg/g). The order of ABTS radical and alkyl radical scavenging activities was as follows: AE > BE > OE > HWSE > HWASE. The antioxidant properties were considerably correspondent with the total polyphenol and flavonoid content. DPPH radical scavenging activity was quite high in HWSE, AE, and BE extraction, however, there were no significant differences among the five extraction methods in the aspect of $Fe^{2+}$ ion chelating activities. Moreover, AE showed the highest SOD activity, and protected the dermal fibroblast the best against $H_2O_2$-induced cytotoxicity. In conclusion, it was suggested that the autoclave extraction (AE) would be the most effective method for preparing blueberry hot water extracts with relatively high antioxidant activities.

Change of asparagine content in soybean sprouts by variety, root growth, and cultivation period (콩나물의 품종, 뿌리발생 및 재배일수에 따른 asparagine 함량 변이)

  • Jeong, Yeon-Shin;Park, Hee Joon;Dhakal, Krishna Hari;Lee, Jeong-Dong;Lee, In-Jung;Hwang, Young-Hyun
    • Current Research on Agriculture and Life Sciences
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    • v.26
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    • pp.63-69
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    • 2008
  • The varietal difference, effect of root amounts and cultivation duration on the asparagine content of soybean sprouts, which is known to have the excellent detoxifying effect of ethanol, were investigated for developed varieties and indigenous sprout lines to establish cultivation methods of increasing the asparagine content and to develop soybean varieties having high asparagine content. Some of the research results obtained are summarized as follows; 1. Range and mean of asparagine content of 174 germplasm were 0.38~1.67% and 0.99%, respectively, on fresh weight basis. 2. Developed sprout-soybean varieties showed somewhat higher asparagine content of 1.29% than that of indigenous sprout lines of 0.96% on fresh weight basis. 3. No significant difference in asparagine content among the seed size groups was recognized though the highest asparagine content, 1.02% on fresh weight basis was observed in the seed size of 8.1~10.0g/100 seeds. 4. Among the seed coat color groups, soybean of brown seed coat color showed the highest asparagine content (1.15%) on fresh weight basis. No difference was observed among other groups of seed coat color. 5. Range of asparagine content of 174 varieties was 4.08~6.24% on dry weight basis. Soybean varieties that showed high asparagine content were Dawonkong, Sobacknamulkong, Sowonkong, and Somyungkong, with the contents of 6.24%, 6.21%, 5.95%, and 5.85%, respectively. 6. Amount of roots which have the highest asparagine content out of sprout parts was greatly increased up to 10 days of sprout cultivation. 7. Highly significant difference in asparagne content of sprout was recognized between those grown for five and ten days, with the asparagine content of 0.68% and 1.21%, respectively, on fresh weight basis. 8. Asparagine content of hypocotyle part was also highly proportional to days to cultivation; it increased from 2.91% at 2 days of cultivation to 15.68% on fresh weight basis at 14 days of cultivation.

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Spatio-temporal Characteristics of Macrobenthic Community in the Coastal area of South Korea (우리나라 연안 대형저서동물 시·공간 군집 특성 분석)

  • KIM, Young-Jun;IM, Jung-Ho;CHO, Chun-Ok;RYU, Jong-Seong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.3
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    • pp.100-117
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    • 2022
  • This study examines the spatio-temporal characteristics of the macrobenthic community in the coastal areas of South Korea for the past six years(2015-2020). The relationship between the number of individuals of macrobenthic species and the benthic environments were investigated using data collected at a total of 154 stations located in the West (70), the South (61), and the East Seas (23), except for the Jeju Sea. We examined the benthic environmental characteristics such as water depth, sediment, grain size, ignition loss, and total organic carbon. A total of 1,614 macrobenthic species were found in the coastal area, with a mean density of 0.62 ind./m2 by station. The mean density was relatively high in the spring and summer seasons (May to August) with more than 450 species. The most dominant species belong to Polychaetes and the top five of them accounted for more than 20% of the total number of populations. The top five species were Heteromastus filiformis, Scoletoma longifolia, Sigambra tentaculata, Sternaspis scutata, and Notomastus latericeus. Cluster analysis was performed on the top five dominant species. The stations were clustered into three groups with similar locations on the West, South, and East Sea. Cluster 1 and 3 represent Heteromastus filiformis (44% each), but cluster 2 represents Scoletoma longifolia (66%). Each cluster has different benthic environmental characteristics, especially in the sediment's sand (31.0%, 51.9%) and clay (15.9%, 9.7%) contents.

Influence of Bicarbonate Concentrations in Nutrient Solution on the Growth, Occurrence of Daughter Plants and Nutrient Uptake in Vegetative Propagation of 'Seolhyang' Strawberry (양액의 중탄산 농도가 '설향' 딸기의 생육, 자묘 발생 및 무기이온 흡수에 미치는 영향)

  • Lee, Hee Su;Choi, Jong Myung;Kim, Tae Il;Kim, Hyun Sook;Lee, In Ha
    • Horticultural Science & Technology
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    • v.32 no.2
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    • pp.149-156
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    • 2014
  • The objective of this research was to investigate the influence of bicarbonate ($HCO_3{^-}$) concentrations in nutrient solution on the growth and physiological disorders in mother plants and occurrence of daughter plants in propagation of 'Seolhyang' strawberry (Fragaria ${\times}$ ananassa Duch.). To achieve this, the mother plants were transplanted to coir dust + perlite (7:3, v/v) medium and Hoagland solution was modified to contain 60, 90 (control), 120, 180, and $240mg{\cdot}L^{-1}$ of $HCO_3{^-}$. The symptoms of Fe, Zn and B deficiencies appeared on the mother plants in the $HCO_3{^-}$ of $240mg{\cdot}L^{-1}$ from the 60th day after treatment. The symptoms spread to all plants in the $240mg{\cdot}L^{-1}$ $HCO_3{^-}$ including daughter plants at 90 days after treatment. The$HCO_3{^-}$ concentrations higher than $120mg{\cdot}L^{-1}$ suppressed the growth of mother plants such as leaf number, chlorophyll content, fresh weight and other growth parameters. While the mother plants in $60mg{\cdot}L^{-1}$ $HCO_3{^-}$ produced 23 daughter plants, while mother plants in $240mg{\cdot}L^{-1}$ $HCO_3{^-}$ produced 13 daughter plants. The final pH 126 days after treatment in the $HCO_3{^-}$ of 60, 90, 120, 180 and $240mg{\cdot}L^{-1}$ were 5.4, 5.8, 7.3, 7.9, and 8.3, respectively. The elevation of $HCO_3{^-}$ concentrations in nutrient solution resulted in the decrease of Fe, Mn, Zn and Cu contents of above ground tissue 126 days after treatment. These results indicate that the $HCO_3{^-}$ concentrations higher than $120mg{\cdot}L^{-1}$ inhibited the growth of mother plants and occurrence of daughter plants in vegetative propagation of 'Seolhyang' strawberry.

Change of Fragrant Components by Flowering Stages in Lilium Oriental Hybrid 'Casa Blanca' (오리엔탈 나리 '카사블랑카'의 개화단계별 향기성분 변화)

  • Rho, A Ran;Pak, Chun Ho
    • Horticultural Science & Technology
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    • v.19 no.2
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    • pp.163-169
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    • 2001
  • This experiment was conducted to find out suitable extraction time of available fragrant component in Lilium Oriental Hybrida 'Casa Blanca' based on qualitative and quantitative variation of its fragrant component in its flowering stages. The content of essential oil in its flowering stages increased with the progress of flowering stages except flower bud stage and it had the most oil content in its stage after full bloom. The analysis of the essential oil in Lilium Oriental Hybrida 'Casa Blanca' in its flowering stages shows that its main constituents were farnesol (18.96%), benzyl salicylate (13.81%), butyl-hydroxy toluene (12.87%), geranyl linalool isomer (7.46%), isoeugenol (7.17%) in its each stage. Benzenoids had much content at half bloom stage and full bloom stage while fatty acid derivatives had much content at initial flowering stage and after flowering stage. Most benzenoids such as butyl-hydroxy toluene and isoeugenol, which are some of main constituents of Lilium Oriental Hybrida 'Casa Blanca' had strong antioxidant effect. So they were expected to be used as antioxidant agents for food, feed, vegetable oil. The content of monoterpene compounds like geranyl linalool isomer increased at its later stage. Sesquiterpene such as farnesol, which is main component of lily existed only at full bloom stage. Therefore farnesol and geranyl linalool isomer of Lilium Oriental Hybrida 'Casa Blanca' are expected to be used for important spices with good fragrance. The suitable extraction time for the usable main constituents of Lilium Oriental Hybrida 'Casa Blanca' is as follows; farnesol and benzyl salicylate: at full bloom stage, butyl-hydroxy toluene: at half bloom stage, geranyl linalool isomer and isoeugenol: at stage after full bloom. Finally there was variation in essential oil components and contents of Lilium Oriental Hybrida 'Casa Blanca' in its flowering stages and they are expected to be used usefully for flavor industry, food industry, aromatherapy, when they are extracted at their suitable extraction time.

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Comparison of the Antioxidant Activities of Organic Solvent Fractions of Leaf and Root Extracts of Peucedanum insolens Kitagawa (왕산방풍의 잎과 뿌리의 유기용매 분획물에서의 항산화 활성 비교)

  • Myong-Seok Oh;Nandintsetseg Narantuya;Chan-Ju Park;Ghilsoo Nam;Sik-Jae Cho;Ja-Young Moon
    • Journal of Life Science
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    • v.33 no.2
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    • pp.138-148
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    • 2023
  • This study compared and analyzed the antioxidant activities of various organic solvent fractions from the leaves and roots of Peucedanum insolens Kitagawa. For this study, the dried leaves and roots of P. insolens Kitagawa were first extracted using 70% ethanol. The extracts were sequentially sub-fractionated in the order of hexane, chloroform, ethyl acetate, n-butanol, and water. The results revealed that the distribution of total phenolic contents by organic solvent fractions showed the same pattern in both the leaves and roots, with the highest in the ethyl acetate fraction (101.1±1.0 mg vs 71.2±3.4 mg of GAE/mg), but the lowest content in the hexane fraction (9.5±0.2 mg vs 7.5±2.1 mg of GAE/mg). The distribution of total flavonoid content in the organic solvent fractions showed the same pattern as that of total phenolic content. The results of DPPH, ABTS, and FRAP assays showed that the leaf and root extracts exhibited free radical scavenging activity in the same pattern, particularly, the ethyl acetate fraction had the highest activity. These results indicate that not only the roots of P. insolens Kitagawa but also the leaves possess potential substances that exhibit strong antioxidant activity. Significant correlations (R=0.903, p<0.0001, DPPH radical; R=0.891, p<0.001, ABTS radical; R=0.745, p<0.05, FRAP radical) between total phenolics and radical scavenging activities, but also significant correlations (R=0.867, p<0.001, DPPH vs. ABTS radicals; R=0.882, p<0.0001, DPPH vs. FRAP radicals; R=0.973, p<0.0001, ABTS vs. FRAP radicals) between radical scavenging activities were found in the organic solvent fractions. Therefore, as in the roots of P. insolens Kitagawa, the leaves possess strong antioxidant capacity and can be used as the main antioxidant material.

A Study on the PCDDs/PCDFs Contents in the Flue Gas of Muncipal Solid Waste Incinerator(III) -Emission Concentration Varying the Combustion Temperature- (쓰레기소각로 배출가스의 PCDDs/PCDFs 함유량에 관한 연구(III) -소각로 연소 온도변화에 따른 보일러 후단에서의 배출 농도 변화-)

  • Shin, S.K.;Chung, Y.H.;Lee, J.I.
    • Analytical Science and Technology
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    • v.12 no.6
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    • pp.540-549
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    • 1999
  • The combustion temperature was controlled between $880^{\circ}C$ to $1070^{\circ}C$ to find the relation the combustion temperature and emission amount of PCDDs/PCDFs in the Municipal solid waste incinerator. The emission amount of PCDDs/PCDFs decreased when the temperature increased in the rear of the boiler. The PCDDs/PCDFs concentration were detected $7.82ng-TEQ/Nm^3$ at $880^{\circ}C$, $6.97ng-TEQ/Nm^3$ at $970^{\circ}C$ and $6.13ng-TEQ/Nm^3$ at $1070^{\circ}C$. Also, The chlorophenols, chlorobenzenes, and PCB concentration decreased by increasing the temperature from $880^{\circ}C$ to at $1070^{\circ}C$, and the isomer of the prescsors had a tendency to emit the higbly cbiorinated compounds.

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