• Title/Summary/Keyword: Nuclear generation

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Adsorption Removal of Sr by Barium Impregnated 4A Zeolite (BaA) From High Radioactive Seawater Waste (Barium이 함침된 4A 제올라이트 (BaA)에 의한 고방사성해수폐액에서 Sr의 흡착 제거)

  • Lee, Eil-Hee;Lee, Keun-Young;Kim, Kwang-Wook;Kim, Ik-Soo;Chung, Dong-Yong;Moon, Jei-Kwon;Choi, Jong-Won
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.2
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    • pp.101-112
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    • 2016
  • This study investigated the removal of Sr, which was one of the high radioactive nuclides, by adsorption with Barium (Ba) impregnated 4A zeolite (BaA) from high-radioactive seawater waste (HSW). Adsorption of Sr by BaA (BaA-Sr), in the impregnated Ba concentration of above 20.2wt%, was decreased by increasing the impregnated Ba concentration, and the impregnated Ba concentration was suitable at 20.2wt%. The BaA-Sr adsorption was added to the co-precipitation of Sr with $BaSO_4$ precipitation in the adsorption of Sr by 4A (4A-Sr) within BaA. Thus, it was possible to remove Sr more than 99% at m/V (adsorbent weight/solution volume)=5 g/L for BaA and m/V >20 g/L for 4A, respectively, in the Sr concentration of less than 0.2 mg/L (actual concentration level of Sr in HSW). It shows that BaA-Sr adsorption is better than 4A-Sr adsorption in for the removal capacity of Sr per unit gram of adsorbent, and the reduction of the secondary solid waste generation (spent adsorbent etc.). Also, BaA-Sr adsorption was more excellent removal capacity of Sr in the seawater waste than distilled water. Therefore, it seems to be effective for the direct removal of Sr from HSW. On the other hand, the adsorption of Cs by BaA (BaA-Cs) was mainly performed by 4A within BaA. Accordingly, it seems to be little effect of impregnated Ba into BaA. Meanwhile, BaA-Sr adsorption kinetics could be expressed the pseudo-second order rate equation. By increasing the initial Sr concentrations and the ratios of V/m, the adsorption rate constants ($k_2$) were decreased, but the equilibrium adsorption capacities ($q_e$) were increasing. However, with increasing the temperature of solution, $k_2$ was conversely increased, and $q_e$ was decreased. The activation energy of BaA-Sr adsorption was 38 kJ/mol. Thus, the chemical adsorption seems to be dominant rather than physical adsorption, although it is not a chemisorption with strong bonding form.

Perilla frutescens Sprout Extracts Protected Against Cytokine-induced Cell Damage of Pancreatic RINm5F Cells via NF-κB Pathway (들깨 새싹 추출물의 췌장 RINm5F 세포에서 NF-κB 경로를 통한 사이토카인에 의한 손상 예방 효과)

  • Kim, Da Hye;Kim, Sang Jun;Jeong, Seung-Il;Yu, Kang-Yeol;Cheon, Chun Jin;Kim, Jang-Ho;Kim, Seon-Young
    • Journal of Life Science
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    • v.27 no.5
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    • pp.509-516
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    • 2017
  • Perilla frutescens (L.) Britton var. sprouts (PFS) is a plant of the labiatae family. The purpose of this work was to assess the preventive effects of PFS ethanolic extracts (PFSEs) on cytokine-induced ${\beta}$-cell damage. Cytokines, which are released by the infiltration of inflammatory cells around the pancreatic islets, are involved in the pathogenesis of type 1 diabetes mellitus. The combination of interleukin-$1{\beta}$ (IL-1), interferon-${\gamma}$ (IFN-${\gamma}$), and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) induced formation of reactive oxygen species (ROS). Accumulation of intracellular ROS led to ${\beta}$-cell dysfunction and apoptosis. PFSEs possess antioxidant activity and thus lead to downregulation of ROS generation. Cytokines decrease cell viability, stimulate the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and induce the production of nitric oxide (NO). PFSEs prevented cytokine-induced cell viability in a dose-dependent manner. Incubation with PFSE resulted in significant reduction in cytokine-induced NO production that correlated with reduced levels of the iNOS and COX-2 protein expression. Furthermore, PFSE significantly decreased the activation of nuclear factor ${\kappa}B$ (NF-${\kappa}B$) by inhibition of $I{\kappa}B{\alpha}$ phosphorylation in RINm5F cells. In summary, our results suggest that the protective effects of PFSE might serve to counteract cytokine-induced ${\beta}$-cell destruction. Findings indicate that consumption of Perilla frutescens (L.) Britton var. sprouts alleviates hyperglycemia-mediated oxidative stress and pro-inflammatory cytokine-induced ${\beta}$-cell damage and thus has beneficial anti-diabetic effects.

International Space Law on the Protection of the Environment (환경보호에 관한 국제 우주법연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.25 no.1
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    • pp.205-236
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    • 2010
  • This article deals with international space law for the environmental protection in outer space especially for space debris arising from space activities. After studying 1967 Outer Space Treaty, 1968 Rescue Agreement, 1972 Liability Convention, 1975 Registration Convention and 1979 Moon Agreement, we could find few provisions dealing with space environment in those treaties. During the earlier stages of the space age, which began in the late 1950s, the focus of international law makers was the establishment of the basic rules of space law governing the states' activities in outer space. Consequently the environmental issues and the risks that might arise from the generation of the space debris did not receive priority attention within the context of the development international space law. Although the phrases such as 'harmful contamination', 'harmful interference', 'disruption of the environment', 'adverse changes in the environment' and 'harmfully affecting' in relation to space environment were used in 1967 Outer Space Treaty and 1979 Moon Agreement, their true meaning was not definitely settled. Although 1972 Liability Convention deals with compensation, whether the space object covers space debris is unclear despite the case of Cosmos 954. In this respect international lawyers suggest the amendment of the space treaties and new space treaty covering the space environmental problems including the space debris. The resolutions, guidelines and draft convention are also studied to deal with space environment and space debris. In 1992 the General Assembly of the United Nations passed resolution 47/68 titled "Principles Relevant to the Use of Nuclear Power Sources in Outer Space" for the NPS use in outer space. The Inter-Agency Space Debris Coordination Committee; IADC) issued some guidelines for the space debris which were the basis of "the UN Space Debris Mitigation Guidelines" approved by COPUOS in its 527th meeting. In 1994 the 66th conference of ILA adopted "International Instrument on the Protection of the Environment from Damage Caused by Space Debris". Although those resolutions, guidelines and draft convention are not binding states, there are some provisions which have a fundamentally norm-creating character and softs laws.

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Ethanol Extract of Glycyrrhiza uralensis Protects Against Oxidative Stress-induced DNA Damage and Apoptosis in Retinal Pigment Epithelial Cells (망막색소상피세포에서 감초 추출물의 산화적 스트레스에 의한 DNA 손상 및 apoptosis 유발의 차단 효과)

  • Kim, So Young;Kim, Jeong-Hwan;Kim, Sung Ok;Park, Seh-Kwang;Jeong, Ji-Won;Kim, Mi-Young;Lee, Hyesook;Cheong, JaeHun;Choi, Yung Hyun
    • Journal of Life Science
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    • v.29 no.11
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    • pp.1273-1280
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    • 2019
  • Age-related macular degeneration (AMD) is one of the leading causes of blindness in the elderly population, and damage to retinal pigment epithelial (RPE) cells due to oxidative stress contributes to the development of AMD. Glycyrrhiza uralensis Fischer is one of the most widely used herbal medicines for the treatment of various diseases in Asian countries. Although recent studies indicated that treatment with G. uralensis can protect cells from oxidative stress, its mechanisms in RPE cells remain unknown. We evaluated the effect of a G. uralensis ethanol extract (GU) on $H_2O_2$-induced oxidative injury in ARPE-19 RPE cells. The GU pretreatment attenuated reactive oxygen species (ROS) generation induced by $H_2O_2$, which was associated with induced expression of nuclear factor erythroid-derived-2-like 2 (Nrf2) and heme oxygenase-1 (HO-1). GU also suppressed $H_2O_2$-induced DNA damage and mitochondrial dysfunction. The inhibitory effect of GU on $H_2O_2$-induced apoptosis was associated with the protection of caspase-3 activation. Overall, GU appeared to protect RPE cells from oxidative injury by inhibiting DNA damage and reducing apoptosis. Further studies are needed to determine the regulation of Nrf2-mediated HO-1 expression, but our results suggest the possibility of using GU to reduce the risk of AMD.

Production of doubled haploid population derived from the microspore culture of rapeseed (Brassica napus L.) F1 generation and analysis of fatty acid composition (유채 잡종 1세대의 소포자 배양에 의한 배가반수체 집단 선발 및 지방산 조성 분석)

  • Lee, Ji Eun;Park, Ju Hyun;Kim, Kwang Soo;An, Da Hee;Cha, Young Lok
    • Journal of Plant Biotechnology
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    • v.49 no.1
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    • pp.74-81
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    • 2022
  • Brassica napus, an oil crop that produces rapeseed oil, is an allotetraploid (AACC, 2n = 38) produced by natural hybridization between B. rapa and B. oleracea. In this study, microspore was cultured using the F1 developed from a cross between 'EMS26' line with high oleic acid content and 'J8634-B-30' lines. The flower bud size showing the nuclear development at the late uninucleate and binucleate stage with high embryogenesis rate was 2.6 ~ 3.5 mm. Microspores were cultured using only this size and after then most microspore embryo developed into secondary embryos and then regeneration plants obtained from the developed multilobe. The analysis of the ploidy of the plants revealed that 66.7% and 27.8% of the total lines were tetraploids and octoploids, respectively. The sizes of stomatal cells in tetraploids, octoploids, and diploids were 25.5, 35.6, and 19.9 ㎛, respectively, indicating that ploidy level was positively correlated with cell size. Furthermore, 62 tetraploid doubled haploid (DH) lines were selected. The average oleic acid (C18:1) and linolenic acid (C18:3) concentrations of DH were 72.3% and 6.2%, respectively. Oleic acid and linolenic acid concentrations exceeded the two parental values in 5 and 14 DH lines, respectively, suggesting that these two fatty acids had transgressive segregation. Therefore, the DH population can be utilized for the biosynthesis of unsaturated fatty acids in rapeseed and related genes. It can also be used as a breeding material for varieties with high oleic acid concentrations.

Pro-inflammatory Cytokine Expression Through NF-${\kappa}B/I{\kappa}B$ Pathway in Lung Epithelial Cells (폐 상피세포에서 NF-${\kappa}B/I{\kappa}B$ 경로에 의한 염증매개 사이토카인의 발현)

  • Park, Gye-Young;Lee, Seung-Hee;HwangBo, Bin;Yim, Jae-Joon;Lee, Choon-Taek;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Yoo, Chul-Gyu
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.3
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    • pp.332-342
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    • 2000
  • Background : The importance of pro-inflammatory cytokines, especially tumor necrosis factor $\alpha$ (INF-$\alpha$) and interleukin-1$\beta$ (IL-1$\beta$), have been extensively documented in the generation of inflammatory lung disease. Lung epithelial cells are also actively involved in initiating and maintaining inflammation by producing pro-inflammatory mediators. Understanding the mechanism of pro-inflammatory cytokine expression in lung epithelial cells is crucial to the development of new therapeutic modalities for inflammatory lung disease. Transcription of most pro-inflammatory cytokines is dependent on the activation of NF-${\kappa}B$. However, the relationship between pro-inflammatory cytokine expression and NF-${\kappa}B/I{\kappa}B$ pathway in lung epithelial cells is not clear. Methods : BEAS-2B, A549, Na-H157, NCI-H719 cells were stimulated with IL-$1{\beta}$ or TNF-$\alpha$ at various times, and then IL-8 and TNF-$\alpha$mRNA expressions were assayed by Northern blot analysis. IL-$1{\beta}$ or TNF-$\alpha$-induced NF-${\kappa}B$ activation was assessed by the nuclear translocation of p65 NF-${\kappa}B$ subunit. The degradation of $I{\kappa}B{\alpha}$ and $I{\kappa}B{\beta}$ by IL-$1{\beta}$ or TNF-$\alpha$stimulation was assayed by Western blot analysis. The phosphorylation of $I{\kappa}B{\alpha}$ was evaluated by Western blot analysis after pre-treating cells with proteasome inhibitor followed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation. The basal level of IKK $\alpha$ expression was evaluated by Western blot analysis. Results: $I{\kappa}B{\alpha}$ and $I{\kappa}B{\alpha}$ was rapidly degraded after 5 minutes of incubation with IL-$1{\beta}$ or TNF-$\alpha$ in BEAS-2B, A549, and NCI-H157 cells. The activation of NF-${\kappa}B{\alpha}$ and the induction of IL-8 and TNF-$\alpha$ mRNA expression were observed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in these cells. In contrast, neither the changes in NF-${\kappa}B/I{\kappa}B$ pathway nor IL-8 and TNF-$\alpha$mRNA expression was induced by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in NCI-H719 cells. IL-$1{\beta}$ and TNF-$\alpha$-induced $I{\kappa}B$ phosphorylation was observed in BEAS-2B, A549, and NCI-H157 cells, but not in NCI-H719 cells. The basal level of IKK$\alpha$ expression was not different between cell. Conclusion : NF-${\kappa}B/I{\kappa}B$ pathway plays an important role in the expression of pro-inflammatory cytokine in most lung epithelial cells. The absence of the effect on NF-${\kappa}B/I{\kappa}B$ pathway in NCI-H719 cells sæms to be due to the defect in the intracellular signal transduction pathway upstream to IKK.

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