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A Preliminary Analysis on the International Management System for the Ocean fertilization with Iron at High Seas (해양 철분 시비(施肥)사업의 국제 관리체제 예비 분석)

  • Hong, Gi-Hoon;Sohn, Hyo-Jin
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.3
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    • pp.138-149
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    • 2008
  • Rapid accumulation of carbon dioxide in the atmosphere for the past century leads to acidify the surface ocean and contributes to the global warming as it forms acid in the ocean and it is a green house gas. In order to curb the green house gas emissions, in particular carbon dioxide, various multilateral agreements and programs have been established including UN Convention of Climate Change and its Kyoto Protocol for the last decades. Also a number of geo-engineering projects to manipulate the radiation balance of the earth have been proposed both from the science and industrial community worldwide. One of them is ocean fertilization to sequester carbon dioxide from the atmosphere through the photosynthesis of phytoplankton in the sea. Deliberate fertilization of the ocean with iron or nitrogen to large areas of the ocean has been proposed by commercial sector recently. Unfortunately the environmental consequences of the large scale ocean iron fertilization are not known and the current scientific information is still not sufcient to predict. In 2007, the joint meeting of parties of the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 and 1996 Protocol (London Convention/Protocol) has started considering the purposes and circumstances of proposed large-scale ocean iron fertilization operations and examined whether these activities are compatible with the aims of the Convention and Protocol and explore the need, and the potential mechanisms for regulation of such operations. The aim of this paper is to review the current development on the commercial ocean fertilization activities and management regimes in the potential ocean fertilization activities in the territorial sea, exclusive economic zone, and high seas, respectively, and further to have a view on the emerging international management regime to be London Convention/Protocol in conjunction with a support from the United Nations General Assembly through The United Nations Open-ended Informal Consultative Process on Oceans and the Law of the Sea.

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Analysis on Estimating Evapotranspiration of Paddy Rice (벼의 증발산량(蒸發散量) 산정(算定)에 관(關)한 실험(實驗) 분석(分析))

  • Suh, Seung Duk;Lee, Jong Kook
    • Current Research on Agriculture and Life Sciences
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    • v.3
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    • pp.28-35
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    • 1985
  • This work Was carried out to obtain the most suitable crop coefficient for the paddy rice growing in Taegu area. The result was due to the comparative measurements of evapotranspiration formula in terms of Blaney & Criddle and eight other formulas with those produced by experiment particularly in this area. The crop coefficient, evapotranspiration and transpiration ratio produced by this research are hopefully expected to be of service in the future calculation of evapotranspiration without repeating experiment respectively, whenever the water requirement of paddy rice is planned in Taegu and its vicinity. The accomplished results could be summarized as follows : The maximum amount of evapotranspiration was recorded in the early and middle parts of August. The average reading of evapotranspiration was 6.33mm/day throughout the growth. The evapotranspiration had a highly significant correlation with pan evaporation, solar radiation, sunshine hours and relative humidity of meteorological elements. K and Kc by the use of Blaney & Criddle formula calculated at 0.76 to 1.45 and 0.82 to 1.27, respectively. Its peak value appeared commonly in early August. The ratio of transpiration was 269.03.

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Variations of Temperature and Salinity in Kugum Suro Channel (거금수로 해역의 수온과 염분의 변동)

  • CHOO Hyo-Sang;LEE Gyu-Hyong;YOON Yang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.2
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    • pp.252-263
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    • 1997
  • Temperature and salinity were observed in Kugum Suro Channel in February, April, August and October 1993. Temperature ranged from $7.0^{\circ}C\;to\;25.0^{\circ}C$ throughout the year and its variation was about $18^{\circ}C$. The maximum temperature difference between surface and bottom was less than $0.75^{\circ}C$ for a year, which meant that the temperature stratification in Kugum Suro Channel was considerably week. Salinity had also a small variation range of less than $0.5\%_{\circ}$. Salinity varied from $34.0\%_{\circ}$ in April to $30.0\%_{\circ}$ in August and its fluctuation patterns were quite similar to the seasonal variations of the precipitation and the duration of sunshine observed at Kohung Weather station. Seasonal variation of sea water density in T-S diagram showed that the water mass in Kugum Suro Channel could be largely affected by regional atmospheric conditions. Temperature increased in ebb tide and decreased in flood tide, but salinity decreased in ebb tide and increased in flood tide for a day. The period of fluctuations in temperature and salinity measured for 25 hours was nearly coincident with the semi-diurnal tide which was predominant in that region. Stratification parameters computed in Kugum Suro Channel areas were less than $4.0J/m^3$ the year round, which indicated that vortical mixing from the bottom boundary caused by tidal current played an important role in deciding the stratification regime in Kugum Suro Channel. In estimating the equation which defines stratification and mixing effects in the observed areas, the tidal mixing term ranged from $4.7J/M^3\;to\;14.1J/m^3$ was greater than any other terms like solar radiation, river discharge and wind mixing.

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Source Term Characterization for Structural Components in $17{\times}17$ KOFA Spent Fuel Assembly ($17{\times}17$ KOFA 사용후핵연료집합체내 구조재의 방사선원항 특성 분석)

  • Cho, Dong-Keun;Kook, Dong-Hak;Choi, Heui-Joo;Choi, Jong-Won
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.4
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    • pp.347-353
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    • 2010
  • Source terms of metal waste comprising a spent fuel assembly are relatively important when the spent fuel is pyroprocessed, because cesium, strontium, and transuranics are not a concern any more in the aspect of source term of permanent disposal. In this study, characteristics of radiation source terms for each structural component in spent fuel assembly was analyzed by using ORIGEN-S with a assumption that 10 metric tons of uranium is pyroprocessed. At first, mass and volume for each structural component of the fuel assembly were calculated in detail. Activation cross section library was generated by using KENO-VI/ORIGEN-S module for top-end piece and bottom-end piece, because those are located at outer core with different neutron spectrum compared to that of inner core. As a result, values of radioactivity, decay heat, and hazard index were reveled to be $1.40{\times}10^{15}$ Bequerels, 236 Watts, $4.34{\times}10^9m^3$-water, respectively, at 10 years after discharge. Those values correspond to 0.7 %, 1.1 %, 0.1 %, respectively, compared to that of spent fuel. Inconel 718 grid plate was shown to be the most important component in the all aspects of radioactivity, decay heat, and hazard index although the mass occupies only 1 % of the total. It was also shown that if the Inconel 718 grid plate is managed separately, the radioactivity and hazard index of metal waste could be decreased to 20~45 % and 30~45 %, respectively. As a whole, decay heat of metal waste was shown to be negligible in the aspect of disposal system design, while the radioactivity and hazard index are important.

Adolescent obesity and the elevation of aminotransferase levels (청소년 비만과 혈청 아미노 전이 효소 증가)

  • Kim, Su Yeon;Lee, Ho Jun;Park, Tae Su;Kim, Soo Geun;Shin, Hye Jung
    • Clinical and Experimental Pediatrics
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    • v.49 no.10
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    • pp.1037-1041
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    • 2006
  • Purpose : The prevalence of obesity and nonalcoholic steatohepatitis(NASH) was increased in adolescents. This study was performed to observe the prevalence of elevated aminotransferase levels in adolescents and to assess the correlations between aminotransferase levels and obesity related parameters(body mass index, waist circumference, hip circumference, waist to hip ratio and insulin level). Methods : We obtained weight, height, waist circumference and hip circumference from 2,417 male and 1,219 female adolescents. Mean age was $15.7{\pm}0.7$ years old. We measured fasting insulin, aspartate aminotransferase(AST) and alanine aminotransferase(ALT). Obese and overweight were defined as body mass indices(BMI) of more than the 95th, and 85th-94th percentiles, respectively, for age and sex. Results : The number of adolescents with obesity is 324(8.9 percent). 414(11.4 percent) subjects belonged to the overweight group. The average ALT level of obese, overweight and control groups were significantly different(obese : $32.1{\pm}34.3U/L$, overweight : $19.6{\pm}13.6U/L$, control : $12.7{\pm}6.7U/L$, P<0.001). The average AST level was also different according to group(obese : $27.8{\pm}16.5U/L$, overweight : $22.8{\pm}8.6U/L$, control : $20.8{\pm}8.5U/L$, P<0.001). AST and ALT were correlated with anthropometric parameters and insulin level. After multiple regression analysis, waist circumference was the significant predictive value for AST(r=0.234, P<0.001). Waist circumference, BMI and insulin levels were significant predictive values for ALT(r=0.435, P<0.001). Conclusion : The prevalence of abnormal aminotransferase was higher in the obese and overweight groups than control group. Waist circumference was useful to predict abnormal aminotransferase levels.

Experimental Study for the Teratogenic Effect of Gamma-ray on the Heart of Chick Embryo (계태에서 감마선 조사에 의한 심장기형 발생에 관한 실험적 연구)

  • Jo, Yong Whan;Kim, Nam Su;Moon, Sung Yup;Yum, Myeng Gul;Kim, Sung Hoon;Chun, Ha Chung;Kim, Yong Joo;Lee, Hahng
    • Clinical and Experimental Pediatrics
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    • v.46 no.6
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    • pp.554-560
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    • 2003
  • Purpose : To investigate the teratogenic effect of gamma-ray on the heart of chick embryo. Methods : 50 rad, 100 rad, 150 rad, 200 rad, 250 rad, and 300 rad of gamma-ray were used to irradiate three days old chick embryos. The control group was not irradiated. After three weeks, the embryos were sacrificed and examined for cardiovascular malformation. Results : The survival rate of the gamma-ray irradiated group was significantly lower than that of the control group(33.3-63.3% vs 76.4%, P=0.001). The cardiac malformation rate of the experimental group was 11.0%. In the control group, no congenital cardiac malformations were observed. The experimental groups had a significantly higher malformation rate(P=0.001). The types of malformation were ventricular septal defect, tricuspid atresia, Ebstein anomaly and aortic arch anomaly. In the gamma-ray irradiated group, the cardiac malformations were : 14 small ventricular septal defects (VSDs), five large VSDs, two tricuspid atresias, and one Ebstein anomaly. The higher the dose of radiation applied, the higher the incidence of cardiac malformation was noted. Conclusion : Gamma-ray irradiation of 3 days old chick embryos increased the rate of death and the rate of cardiac malformation significantly.

Radurization Effect of Korean Mackerel (한국산 고등어의 방사선 조사효과)

  • CHO S. J.;CHOE Y. K.;LEE S. Y.;BYUN S. M.;CHUNG J. R.
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.3
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    • pp.219-226
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    • 1985
  • To investigate potential application of radurization technique as an effective tool for controlling histamine accumulation, histamine contents were determined in fresh Korean mackerel meat samples irradiated at six dose levels of gamma radiation up to 1 Mrad during 35 day-storage at $0^{\circ},\;5^{\circ}\;and\;10^{\circ}C$. Total bacterial counts, total volatile bases and trimethylamine contents were also estimated. The minimum and maximum doses for Korean mackerel were determined to be 0.2 and 0.5 Mrad, respectively. Irradiation induced redening of fish muscle tissue and redening appeared to be dose dependent. At low doses, this redening contributed positively to the overall sensory qualities. At 0.5 and 1.0 Mrad, on the other hand, meat samples were excessively redened to the extent that red and white muscle layers were not readily distinguishable. No appreciable histamine accumulation occured during entire 35 day-storage in fresh mackerel meats, whether irradiated or not, when they were kept at ice temperature. At $5^{\circ}C$, histamine started to accumulate slightly during late storage in the samples irradiated at low doses. Even in the unirradiated samples, the histamine accumulation did not exceed the level of 10.0 mg per 100g meat until the 28th day at $5^{\circ}C$. At $10^{\circ}C$, however, histamine accumulation in the unirradiated was phenomenal from very early storage and the values reached 827.5 mg per 100g meat by the 35th day, while histamine accumulation in the irradiated was severely suppressed. Irradiation invariably brought about a significant reduction of initial microflora, disrupting normal spoilage pattern. This was reflected in the suppression of not only histamine but also total volatile bases and trimethylamine accumulation during post-irradiation storage at refrigerated temperatures.

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Cell Protective Effects of Enzymatic Hydrolysates of Citrus Peel Pectin (귤피 펙틴 유래 효소적 가수분해물의 세포 보호 효과)

  • Kwon, Soon Woo;Ko, Hyun Ju;Bae, Jun Tae;Kim, Jin Hwa;Lee, Geun Soo;Pyo, Hyeong Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.1
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    • pp.75-85
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    • 2016
  • Pectin, a naturally occurring polysaccharide, has in recent years attracted considerable attention. Its benefits are increasingly appreciated by scientists and consumers due to its safety and usefulness. The chemistry and gel-forming characteristics of pectin have enabled to be used in pharmaceutical industry, health promotion and treatment. Yet, it has been rarely used in cosmetics because of its incompatibility with many cosmetic ingredients, including alcohols, and unstable viscosity of pectin gels under various pH and salt conditions. However, low-molecular-weight pectin oligomers have excellent biological activities, and depolymerization of pectin to produce cosmetic ingredients would be very useful. In this study, we attempted the development of cosmetic ingredients using pectin with an excellent effect on human skin. We developed a bio-conversion process that uses enzymatic hydrolysis to produce pectin hydrolysates containing mainly low-molecular-weight pectin oligomers. Gel permeation chromatography was used to determined the ratio of hydrolysis. The molecular weight of the pectin hydrolysates obtained varied between 200 and 2,700 Da. The two newly developed low-molecular-weight pectin hydrolysates, LMPH A and B, had higher anti-oxidative activities than pectin or D-galacturonic. Exposure to UVB radiation induces apoptotic cell death in epidermal cells. Annexin V binding and propidium iodide uptake were measured by flow cytometry to evaluate UVB-induced cell death in HaCaT cells. Both LMPH A and B reduced UVB-induced cell death and increased cell proliferation by 22% and 30% at 0.5% concentration respectively, while pectin had no significant activity. In conclusion, this study suggests that the newly developed low-molecular-weight pectin hydrolysates can be used as safe and biologically active cosmetic ingredients.

Antioxidative Effect and Component Analysis of Eriobotrya japonica Leaf Extracts (비파엽 추출물의 항산화 효능과 성분분석)

  • Kim, Su-Ji;Park, Jin-O;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.1
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    • pp.57-65
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    • 2012
  • In the present study, the antioxidative properties, inhibitory activity on tyrosinase, and active components of Eriobotrya japonica (E. japonica) leaf extract were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract/fraction of E. japonica leaf was in the order 50 % ethanol extract ($22.625{\mu}g/mL$) < ethyl acetate fraction (6.75) < deglycosylated aglycone fraction (5.06). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of fraction/extracton ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescenceassay were investigated. $OSC_{50}$ of the ethyl acetate fraction, deglycosylated aglycone fraction, and ethanol extract were 0.75, 0.79, and $1.61{\mu}g/mL$, respectively. The cellular protective effects of E. japonica leaf extract on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The protective effects of extract/fraction of E. japonica leaf were increased in a in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). Especially, ${\tau}50$ of ethyl acetate fraction at concentrations of $10{\mu}g/mL$ and $50{\mu}g/mL$ showed the most protective effects at 390.8 min and 1471.5 min. The inhibitory effect ($IC_50$) on tyrosinase of E. japonica leaf extracts was higher than arbutin, known as a skin-whitening agent. The order of inhibitory effects was acetate fraction ($75.25{\mu}g/mL$) < 50 % extract (74.1) < deglycosylated aglycone fraction (43.35). TLC of the ethyl acetate fraction showed 7 bands (EJL 1 - EJL 7). HPLC of the aglycone fraction exhibited 2 peaks, kaempferol and quercetin. The amounts of kaempferol and quercetin were 53.7 and 46.3 %. respectively. Therefore, The amounts of kaempferol and its glucoside were a little bit higher than quercetin and its glucoside in E. japonica leaf extract. Accordingly, these findings suggest that extracts/fractions of E. japonica leaf can function as antioxidants in biological systems, especially skin exposed to UV radiation, and protect cellular membranes against ROS. Thus, the extract/fraction of E. japonica leaf may be used in novel functional cosmetics as antioxidants against skin photoaging.

Antioxidative Properties of Extract/Fractions of Suaeda asparagoides and Salicornia herbacea Extracts(I) (함초(나문재 및 퉁퉁마디) 추출물의 항산화 작용에 관한 연구(I))

  • Park, Soo-Nam;Jeon, So-Mi;Kim, So-I;Ahn, Jeung-Youb
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.33 no.3
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    • pp.145-152
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    • 2007
  • In this study, the antioxidative effects of Sueada asparagoides and Salicornia herbacea extracts were investigated. The free radical(1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity($FSC_{50}$) of extract/fractions of Sueada asparagoides was in the order: 100 % ethanol extract(329.33 ${\mu}g/mL$) < 50 % ethanol extract(40.73) < ethylacetate fraction(13.87) < deglycosylated aglycone fraction (7.80). In case of Salicornia herbacea, the free radical scavenging activities of ethylacetate fraction and aglycone fraction were 13.87 and 7.80 ${\mu}g/mL$, respectively. Reactive oxygen species(ROS) scavenging activities($OSC_{50}$) of Sueada asparagoides and Solicornia herbacea extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity of Sueada asparagoides extracts was 50 % ethanol extract($OSC_{50}$, $0.99{\mu}g/mL$) < ethylacetate fraction (0.05) < aglycone fraction (0.03). Aglycone fraction showed the most prominent scavenging activity. In case of Salicornia herbacea, the ROS scavenging activities of ethylacetate fraction and aglycone fraction were 0.10 and 0.20 ${\mu}g/mL$, respectively. The protective effects of extract/fractions of Sueada asparagoides and Salicornia herbacea on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethanol extract(100%) of Sueada asparagoides diminished photohemolysis in a concentration dependent manner($1{\sim}100{\mu}g/mL$). Particularly deglycosylated aglycone fraction exhibited the most prominent celluar protective effect($\tau_{50}$, 310 min at 50 ${\mu}g/mL$). In case of Salicornia herbacea, ethylacetate fraction exhibited more potent protective effect. These results indicate that extract/fractions of Sueada asparagoides can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS.