• Title/Summary/Keyword: U-50

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산소 플라즈마에 의한 U/UO_2 산화 가속화 연구

  • 양용식;서용대;김용수
    • Proceedings of the Korean Nuclear Society Conference
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    • 1998.05b
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    • pp.41-47
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    • 1998
  • 플라즈마를 이용한 핵연료재료 건식처리 공정 기초연구로서 플라즈마 기체에 의한 U와 $UO_2$의 산화가속화 연구를 수행하였다. $UO_2$에서는 플라즈마를 사용할 경우 40$0^{\circ}C$에서 약 300%정도, 50$0^{\circ}C$에서는 70%정도의 산화가속화가 일어났으며 금속우라늄의 경우에는 35$0^{\circ}C$에서 50%정도의 산화가속화를 확인할 수 있었고 power가 증가함에 따라 산화량이 증가하는 것을 알 수 있었다. 한편 전체적인 실험 결과가 시간에 따라 산화량이 선형적으로 증가하는 것으로 나타나 400~50$0^{\circ}C$에서는 표면반응이 중요한 반응이라는 것을 확인하였다.

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Antioxidative Activities and Tyrosinase Inhibitory Effects of Korean Medicinal Plants

  • Heo, Seong-Il;Jung, Mee-Jung;Kim, Min-Kyeong;Wang, Myeong-Hyeon
    • Journal of Applied Biological Chemistry
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    • v.50 no.3
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    • pp.115-119
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    • 2007
  • To discover the sources with antioxidant and tyrosinase inhibitory activities in Korean traditional medicines, 10 extract of medicinal plants were screened for their potential to scavenge stable 1,1-diphenyl-2-picryhydrazyl (DPPH) free radical, inhibit hydroxyl radical (${\cdot}OH$), total phenolic content, and inhibition of tyrosinase. The potency of DPPH radical scavenging activity was shown in the extract of Ulmus davidiana var. japonica Nakai that has a greater effect with $IC_{50}$ values of $6.49{\pm}5.43{\mu}g/mL$, than BHA ($IC_{50}=20.99{\pm}0.74{\mu}g/mL$), L-ascorbic acid $(IC_{50}=20.59{\pm}1.06{\mu}g/mL),\;and\;{\alpha}-tocopherol\;(IC_{50}=25.55{\pm}0.26{\mu}g/mL)$ as a positive control. The ${\cdot}OH$ scavenging activities were observed in the plants tested. Acanthopanax senticosus, Cirsium setiders, U. davidiana exhibited scavenging activity of more than 60% at $500{\mu}g/mL$. The scavenging activity(%) of BHA and a-tocopherol were 64.32 and 55.87% at $500{\mu}g/mL$, respectively. The total phenolic content was determined, in order to assess its effect on the extract's antioxidant activity. The total phenoic content of $33.37{\pm}0.52mg/g$ was conformed by methanolic extract of U. davidiana. The U. davidiana and Morus bombycis exhibited tyrosinase inhibitory activity with a $34.28{\pm}1.32\;and\;75.57{\pm}1.10%$, respectively. In particular, M. bombycis has stronger tyrosinase inhibitory activity than albutin with $36.48{\pm}3.56%$ as a positive control. This work showed that the inhibitory abilities of Korean medicinal plants, such as U. davidiana and M. bombycis, on DPPH free radical, inhibit hydroxyl radical (${\cdot}OH$), and inhibition of tyrosinase and total phenolic content, can be useful in the prevention and treatment of free radical-relate disease. Investigations into further isolation of inhibitory principles of U. davidiana and M. bombycis are now in progress.

Aromatic diamine JSH-21 inhibits LPS-induced NO production by targeting NF-kB signaling

  • Shin, Hyun-Mo;Jung, Sang-Hun;Min, Kyung-Rak;Kim, Young-Soo
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.151.3-152
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    • 2003
  • Aromatic diamine JSH-21 showed an IC50 value of 9.2 uM with 74.5% inhibition at 30 uM, 53.5% at 10 uM and 24.5% at 3 uM on LPS-induced NO production in murine macrophages Raw 264.7. To examine whether inhibitory effect on NO production by JSH-21 was attributed to influence on iNOS expression, iNOS transcript and protein were analyzed by sequantitative RT-PCR and immunoblot analysis. Consistent with previous result on NO production, treatment of the Raw 264.7 cells with JSH-21 decreased the LPS-induced expression of iNOS transcript and protein in a dose-dependent manner with IC50 values of about 10 uM. (omitted)

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Structure-Activity Relationships of Fungicidal N-Substituted Phenyl 1,3,5- Trimethylpyrazole-4-carboxamides in the Inhibition of Succinate Dehydrogenase (SDH) Isolated from Rhizoctonia solani $K{\ddot{u}}hn$ (벼 잎집무늬 마름병균 (Rhizoctonia solani $K{\ddot{u}}hn$)에서 분리한 Succinate Dehydrogenase (SDH) 에 대한 N-치환 phenyl 1,3,5-trimethylpyrazole-4-carboxamide 유도체의 효소활성저해)

  • Kim, Yong-Whan
    • Applied Biological Chemistry
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    • v.40 no.5
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    • pp.447-450
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    • 1997
  • Eighteen N-substituted phenyl 1, 3, 5-trimethylpyrazole-4-carboxamides were synthesized to screen for their mycelial growth inhibition activity against Rhizoctonia solani $K{\ddot{u}}hn$ $(pEC_{50})$ and to measure enzymatic inhibition activity of these compounds $(pI_{50})$ against succinate dehydrogenase (SDH) isolated from Rhizoctonia solani $K{\ddot{u}}hn$ A structure-activity relationship formulated by regression analysis showed that 79% of the variance in mycelial growth inhibition activity can be explained with SDH inhibition activity and chromatographic capacity factor $(\acute{k})$ as a hydrophobic parameter related to the penetration and transport processes in the biological system.

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Effects of a Customized Health Promotion Program on Depression, Cognitive Functioning, and Physical Health of Elderly Women Living Alone in Community: A Cluster Randomized Controlled Trial (맞춤형 건강증진 프로그램이 여성 독거노인의 우울과 인지기능 및 신체 건강에 미치는 효과: 무작위 집락 배정 설계)

  • Park, Ye Ri Ja;Sohng, Kyeong-Yae
    • Journal of Korean Academy of Nursing
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    • v.49 no.5
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    • pp.515-525
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    • 2019
  • Purpose: This study aimed to evaluate the effectiveness of a customized health promotion program (CHPP) on depression, cognitive functioning, and physical health of elderly women living alone in the community. Methods: A randomized comparison of pre-and post-test design was used with 62 participants assigned to either an intervention (n=32 in seven clusters) or a control group (n=30 in seven clusters) in 14 areas of a town. The final sample included 30 intervention participants who completed the CHPP for 10 weeks, and 26 control participants. The intervention group participated in the CHPP weekly; they were provided with instructions about coping with their chronic illnesses, lifestyle modification, risk management, providing emotional support to each other, and floor-seated exercise, which they were encouraged to do three times a week in their homes. Results: Significant group differences were found in depression (U=48.50, p<.001), cognitive functioning (U=2.50, p<.001), left arm flexibility (U=251.50, p=.023), right arm flexibility (U=225.00, p=.007), static balance (U=237.00, p=.012), and gait ability (U=190.50, p=.004). However, there were no significant differences in bothgrip strength and muscle mass between the two groups. Conclusion: The findings indicate that CHPP was overall effective at improving depression, cognitive functioning, and physical functioning of elderly women living alone, and could therefore be considered a positive program for community-dwelling elderly women living alone.

Human Abilities

  • Maker, C. June;Anuruthwong, Usanee
    • Proceedings of the Korean Society for the Gifted Conference
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    • 2005.11a
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    • pp.50-53
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    • 2005
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