• Title/Summary/Keyword: $^{224}Ra$

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Measurements of $^{224}Ra\;and\;^{223}Ra$ in the Nakdong River estuary and the South Sea of Korea

  • Hwang, Dong-Woon;Kim, Gue-Buem;Yang, Han-Soeb
    • Journal of the korean society of oceanography
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    • v.38 no.2
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    • pp.80-86
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    • 2003
  • The horizontal distributions of $^{224}Ra$ (half life=3.4 days) and $^{223}Ra$ (half life=11.3 days) were measured in surface seawaters of the Nakdong River estuary and the South Sea of Korea in April and October 2002. In order to determine these short-lived Ra isotopes, we used a delayed coincidence counter which is much more rapid and accurate than traditional methods. In an estuarine mixing zone (salinity, ~l6 ppt), the activities of $^{224}Ra\;and\;^{223}Ra$ were much greater than what would be expected from a mixture of freshwater and seawater in the Nakdong River estuary. This excess Ra may be a result of Ra desorption from fresh sediments originating from the river upstream. However, in the more open areas of the Nakdong River estuary (salinity>30 ppt) and the South Sea of Korea, $^{224}Ra\;and\;^{^{223}Ra$ activities decreased exponentially as a function of distance offshore. Using the decrease of $^{223}Ra$ with distance offshore in the South Sea of Korea, we estimated the apparent horizontal eddy diffusivities. The apparent eddy diffusion coefficients in South Sea of Korea are calculated to be approximately $3500-8000\;\textrm{m}^2/sec$.

Scavenging Effect of Extract from Perilla frutescens and Rosmarinic Acid from Free Radical and Lipid Peroxidation

  • Wu, Ting Ting;Hwang, Bo-Ra;Cho, Eun-Ju
    • Preventive Nutrition and Food Science
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    • v.16 no.3
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    • pp.224-229
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    • 2011
  • The radical scavenging activity and inhibition effect from lipid peroxidation induced by peroxyl radical of methanol extract from Perilla frutescens and its active compound, rosmarinic acid (RA), were investigated in vitro. The treatment of extract and RA scavenged 1,1-diphenyl-2-picrylhydrazyl, hydroxyl radical (${\cdot}OH$) and nitric oxide in a concentration-dependent manner. In particular, the extract and RA showed strong radical scavenging activity against ${\cdot}OH$, the most toxic and reactive radical. In addition, Perilla frutescens and RA effectively inhibited lipid oxidation induced by sodium nitroprusside and 2,2'-azobis(2-aminopropane) dihydrochloride, determined by the ferric thiocyanate method. The present results suggest that Perilla frutescens and RA play a protective role against oxidative stress induced by free radical and lipid peroxidation.

당귀 methanol 추출물의 생리활성

  • Park, Gyeong-Uk;Choe, Sa-Ra;Hong, Hye-Ran;Kim, Jae-Yong;Son, Mi-Ye;Seo, Gwon-Il
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2007.11a
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    • pp.224.2-224.2
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    • 2007
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Corrosion Characteristics of Pumping-up Power Plant's Pipelines for Efficient Management (양수발전소 배관의 효율적 설계 및 관리를 위한 부식특성 연구)

  • Lee, Hun-Seong;Ra, Hye-Na;Gang, Jun;Kim, Gi-Jun;Mun, Gyeong-Man;Lee, Myeong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.224-224
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    • 2009
  • 양수발전소의 파이프라인 부식에 대해 연구하였다. 파이프의 파공부위에 대한 외관구조분석, 녹 부위에 대한 SEM, XRD, X선 형광분석 및 모재부와 용접부의 전기화학적 분극을 측정하여 파이프라인의 파공과 부식에 대한 원인을 분석-고찰하고 최적의 관리방안을 제시하고자 하였다.

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A Linkage Study of Chromosome 5 D5S39(p105-153Ra), D5S76(p105-599Ha), and $D_2$, $D_3$ Receptor Gene($DRD_2$, $DRD_3$) in Schizophrenics in Korean Pedigree (한국인 정신분열병 가계의 염색체 5번 D5S39(p105-153Ra), D5S76(p105-599Ha) 및 도파민 $D_2$, $D_3$ 수용체 유전자좌간의 연관관계 연구)

  • Oh, Kang-Seob;Kim, Young-Tae;Lee, Min-Soo
    • Korean Journal of Biological Psychiatry
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    • v.1 no.1
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    • pp.67-78
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    • 1994
  • The author examined the relationship of two markers, D5S39(p105-153Ra), D5S76(p105-599Ha) of chromosome 5 and $D_2$, $D_3$ receptor genes in a Korean schizophrenic pedigree using polymerase chain reaction(PCR). The results were as follows : 1) On D5S39 locus, 5 different alleles(224/226 bp : 4 cases, 218/226 bp : 3 cases, 222/226 bp : 3 cases, 218/230 bp : 1 case, 222/224 bp : 1 case) were produced. 2) On D5S76 locus, 5 different alleles(102/112 bp : 4 cases, 94/112 bp : 3 cases, 108/112 bp 3 cases, 94/94 bp : 1 case, 102/108 bp 1 case) were produced. 3) On $D_2$ receptor gene, 3 different alleles($A_1A_2$ : 8 cases, $A_1A_1$ : 2 cases, $A_2A_2$ : cases) were produced. 4) On $D_3$ receptor gene, 2 different alleles(1/2 : 7 cases, 1/1 : 5 cases) were produced. The author had not find any specific alleles on all four loci in all pedigree nor any specific alleles in the schizophrenic patients. Though the author has not found absolute relationship between the four loci and the onset of schizophrenia, there still remains the possibilities if the more detailed and elaborated pedigree studies are done.

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The Effect of Chitosan on the Rheological Properties of Soymilk and Quality Characteristics of Tofu

  • Han, Jin-Suk;Kim. Mee-Ra
    • Preventive Nutrition and Food Science
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    • v.10 no.3
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    • pp.224-230
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    • 2005
  • The effects of low viscosity chitosan on the rheological properties of soymilk using a model system and on tofu qualities were examined. The flow behavior of soy milk with chitosan closed the Newtonian flow and stabilized according to increasing chitosan concentration. The soymilk containing $glucono-\delta-lactone$ exhibited a more pseudoplastic flow behavior compared with that of the control soymilk. The addition of low viscosity chitosan to the tofu preparation did not significantly affect its physicochemical properties. However, the results of the TEM image and instrumental textural properties showed that low viscosity chitosan affected the construction of the tofu structure. Chitosan tofu had low scores across the whole field of appearance in the sensory evaluation, and its overall eating quality was scored significantly lower. These results suggest that the addition of low viscosity chit os an affects the quality of tofu, which changes according to the degree of polymerization and concentration of chitosan.

The study on the corrosion property of Zn-Mg alloy coatings with various Mg contents using EIS method (Mg 함량에 따른 Zn-Mg 박막의 EIS 부식 특성에 관한 연구)

  • Bae, Gi-Tae;Ra, Jeong-Hyeon;Lee, Sang-Yul;Nam, Gyeong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.224-224
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    • 2014
  • 최근 기존의 아연 도금 강판의 성능을 향상시키기 위하여 다른 금속과의 합금 박막의 연구가 활발히 진행 중에 있다. 기존 아연 도금 강판에 비해 Mg를 함유한 Zn-Mg 합금 박막이 내식성이 우수하다고 알려져 있으며, 본 연구에서는 다양한 Mg 함량의 Zn-Mg 합금 타겟을 사용하여 Zn-Mg 박막을 합성하였다. 합성된 박막들의 내식성을 평가하기 위해서 Electrochemical Impedance Spectroscopy (EIS) 분석을 실시하였으며, 도출된 Nyquist plot 과 Bode phase angle plot 결과를 등가회로 피팅과 시뮬레이션을 실시하여 Mg 함량에 따른 Zn-Mg 박막의 내식성을 비교 분석하였다. Zn-Mg 박막은 Mg 함량이 증가할수록 내식성 또한 증가하였으며, 이는 Mg 함량에 따라 치밀해지는 미세구조에 의한 것으로 판단된다.

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Extravascular Migration of a Fractured Inferior Vena Cava Filter Strut

  • Lim, Jung Hyeon;Lee, Weon Yong;Ra, Yong Joon;Jeong, Jae Han;Park, Bong Suk;Ko, Ho Hyun
    • Journal of Chest Surgery
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    • v.50 no.3
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    • pp.224-227
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    • 2017
  • A 20-year-old man presented with a femur fracture and epidural hemorrhage (EDH) following a fall. One month after fracture surgery, swelling developed in both legs, and he was diagnosed as having a deep-vein thrombosis and pulmonary embolism. A retrievable inferior vena cava filter (IVCF) was inserted, because EDH is a contraindication to anticoagulants. Four months later, he complained of abdominal pain, and a computed tomography scan showed a fractured IVCF strut. After percutaneous removal failed 3 times, the IVCF was surgically removed by orthopedists using a portable image intensifier without cardiopulmonary bypass.

Real-time Full-view 3D Human Reconstruction using Multiple RGB-D Cameras

  • Yoon, Bumsik;Choi, Kunwoo;Ra, Moonsu;Kim, Whoi-Yul
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.4
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    • pp.224-230
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    • 2015
  • This manuscript presents a real-time solution for 3D human body reconstruction with multiple RGB-D cameras. The proposed system uses four consumer RGB/Depth (RGB-D) cameras, each located at approximately $90^{\circ}$ from the next camera around a freely moving human body. A single mesh is constructed from the captured point clouds by iteratively removing the estimated overlapping regions from the boundary. A cell-based mesh construction algorithm is developed, recovering the 3D shape from various conditions, considering the direction of the camera and the mesh boundary. The proposed algorithm also allows problematic holes and/or occluded regions to be recovered from another view. Finally, calibrated RGB data is merged with the constructed mesh so it can be viewed from an arbitrary direction. The proposed algorithm is implemented with general-purpose computation on graphics processing unit (GPGPU) for real-time processing owing to its suitability for parallel processing.