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Radiation detector material development with multi-layer by hetero-junction for the reduction of leakage current (헤테르접합을 이용한 누설전류 저감을 위한 다층구조의 방사선 검출 물질 개발)

  • Oh, Kyung-Min;Yoon, Min-Seok;Kim, Min-Woo;Cho, Sung-Ho;Nam, Sang-Hee;Park, Ji-Goon
    • Journal of the Korean Society of Radiology
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    • v.3 no.1
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    • pp.11-15
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    • 2009
  • In this study, the basic research verifying possibility of applications as radiology image sensor in Digital Radiography was performed, the radiology image sensor was fabricated using a multi-layer technique to decrease dark current. High efficiency materials in substitution for Amorphous Selenium(a-Se) have been studied as a direct method of imaging detector in Digital Radiography to decrease dark current by using PN junction or Hetero junction already used as solar cell, semiconductor. Particle-In -Binder method is used to fabricate radiology image sensor because it has a lot of advantages such as fabrication convenient, high yield, suitability for large area sensor. But high leakage current is one of main problem in Particle-In -Binder method. To make up for the weak points, multi-layer technique is used, and it is considered that high efficient digital radiation sensor can be fabricated with easy and convenient process. In this study, electrical properties such as leakage current, sensitivity, signal linearity is measured to evaluate multi-layer radiation sensor material.

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Experimental Studies on the Hair Growth Activity of Drynariae Rhizoma Extracts in C57BL/6N Mice (C57BL/6N 생쥐에서 골쇄보(骨碎補) 추출물을 이용한 발모(發毛)효과에 대한 실험적 연구)

  • Jung, Suk-Young;Jung, Il-Kook;Kim, Dae-Keun;Jo, Han-Young;Jung, Han-Sol;Lee, Chang-Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.2
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    • pp.453-461
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    • 2007
  • Drynariae Rhizoma has been used for promotes mending of the sinews and bone, tonifies the kidney for such symptoms as weak low back and knees, and stimulates the growth of hair as a tinctute for alopecia in oriental medicine. This experiment examined the effect of an acetone extracts of Drynariae Rhizomas(GSB-1), its EtoAc fraction(GB-2) and n-buOH fraction(GSB-3), on hair growth activity of the C57BL/6L mice after topical application to skin. First, We examined on hair growth activity of extracts of Drynariae Rhizomas compare to control and 1 % minoxidil groups. Second, We investigated on the number of hair follicle and mast cells after topical application of extracts of the Drynariae Rhizomas to skin for 16 day. Third, We investigated immunoreactive density of vascular endothelial growth factor(VEGF), protein kinase C-${\alpha}$(PKC-${\alpha}$) and stem(mast) cell factor(SCF) in skin of C57BL/6N mice by immunohistochemical methods. The results were as follows : Hair growth effect of acetone extracts of Drynariae Rhizomas, its EtoAc fraction and n-BuOH fraction was observed in 98 %, 96 % and 60 % in hair removed skin area in 16 day respectively, Immunoreactive density of VEGF in skin of GSB-1 group was weakly stained compare to control group in 10 day, But GSB-2 and GSB-3 groups were mildy stained in bulge and root sheath of skin. Immunolocalization of SCF antigens was observed weakly stained density in epidermis, bulge, stem cells and dermal papilla of control gruop. but in experimental group, immunoreactivity of SCF antigens was observed mildly stained density in bulge, epidermis and root sheath of GSB-1 gruop, heavily stained density in epidermis, bulge and root sheath of GSB-2 and GSB-3 groups to the hair removal skin of C57BL/6N mice on day 10. These experiment suggest that acetone extracts of Drynariae Rhizomas and its EtoAc fraction may be used for topical treatment of alopecia areata.

Studies on the rabbit viral hepatitis : Immunohistochemical observations (토끼의 바이러스성 간염에 관한 연구 : 면역조직화학적 관찰)

  • Lee, Cha-soo;Shin, Tae-kyun;Choi, Youn-ju;Jeong, Kyu-sik;Jyeong, Jong-sik
    • Korean Journal of Veterinary Research
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    • v.33 no.2
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    • pp.269-275
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    • 1993
  • Tissue distribution of RHDV in rabbits were examined by immunofluorescence and ABC methods. Tissues including liver, spleen, kidneys, lungs and brain were frozen, cut in a crycut, and fixed in 10% buffered formalin, embedded in paraplast, and cut $5{\sim}7{\mu}m$ thickness. Sections were immunostained Tissue distribution of RHDV in rabbits were examined by immunofluorescence and ABC methods. Tissues including liver, spleen, kidneys, lungs and brain were frozen, cut in a crycut, and fixed in 10% buffered formalin, embedded in paraplast, and cut $5{\sim}7{\mu}m$ thickness. Sections were immunostained with primary antiserum and conjugated second antibodies as recommended by manufacturer. None of the cultures tested showed virus-induced phenomena. Immunoreactive products were commonly found in the liver, in some cases there were also positive staining in the spleen and kidneys. Other organs showed weak or insignificant immunoreactions. By ABC method on the formalin-fixed, paraffin-embedded liver tissues, strong immunoreactivity was found in the periportal triad lesions and peripheral lesions of the hepatic lobules. Immunoreactive products showed diffuse fine granular in the cytoplasm of hepatocytes and sinusoidal cells. In some cells, immunoproducts marginate at the periphery of the cells. The intensive staining of the cytoplasm of infected cells allowed their exact differentiation from surrounding uninfected cells. The positive area involved coincided with histopathological lesion on serial liver sections. In conclusion, liver was proved to be a consistent target organ in RHD, and the immunoperoxidase method in the section of formalin-fixed, paraffin-embedded hepatic tissue could be broadly used for the routine diagnosis of the disease.

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Sequential pathologic changes and viral distribution in rabbits experimentally infected with new Korean strain of rabbit hemorrhagic disease virus (RHDVa) (새로운 국내 분리 토끼출혈병바이러스(RHDVa)를 감염시킨 토끼에서의 경시적인 병리학적 변화와 조직 내 바이러스 항원 분포)

  • Park, Jung-Won;Chun, Ji-Eun;Yang, Dong-Kun;Bak, Eun-Jung;Kim, Han;Lee, Myeong-Heon;Hwang, Eui-Kyung;Lee, Chung-Bok;Woo, Gye-Hyeong
    • Korean Journal of Veterinary Research
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    • v.52 no.2
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    • pp.125-131
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    • 2012
  • Rabbit hemorrhagic disease is a highly acute and fatal viral disease caused by rabbit hemorrhagic disease virus (RHDV). Since first outbreak in Korea 1987, RHDV has been continually affected in the country, but the pattern of outbreak seem to be changed. In this study, to understand the pathogenesis of the new RHDVa serotype, we therefore carried out to inoculate RHDVa to rabbits, and to examine the sequential histopathologic changes and viral distribution. Macroscopically, various sized dark red or white spots or appearance were observed in the liver, lung, kidney uterus and ureter. In euhanized rabbits, significant pathologic findings such as infiltration of heterophils and mononuclear cells were observed at 24 hours after inoculation (HAI), and these were sequentially extended periportal to centrilobular area. However, in dead rabbits, severe hepatic degeneration and/or necrosis with relatively weak inflammatory responses were observed. RHDV antigens began to detect in liver, spleen, and lung from 12 HAI by PCR. Immunohistochemically, RHDV positive cells were seen in only liver from 24 HAI, and the degree of immunogen reactivity was stronger in dead rabbits than in euthanized ones. In conclusion, RHDVa caused the subacute or chronic infection accompanying low mortality and moderate to severe inflammatory reaction in rabbits, suggesting the possibility that RHD could become endemic.

Purification and Characterization of Lipase from Acinetobacter sp. B2 Isolated from Oil­contaminated Soil (유류오염지역에서 분리한 Acinetobacter sp. B2로부터의 Lipase 정제 및 특성)

  • Son Seung Hwa;Park Kyeong Ryang
    • Korean Journal of Microbiology
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    • v.40 no.4
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    • pp.320-327
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    • 2004
  • Three hundreds thirty two bacterial colonies which were able to degrade crude oil were isolated from soil sam­ples that were contaminated with oil in Daejeon area. Among them, one bacterial strain was selected for this study based on its higher oil degrading ability, and this selected bacterial strain was identified as Acinetobactor sp. B2 through physiological-biochemical tests and analysis of its 16S rRNA sequence. Acinetobactor sp. B2 was able to utilize various carbohydrates but did not utilize trehalose and mannitol as a sole carbon source. Acinetobactor sp. B2 showed a weak resistance to antibiotics such as kanamycin, streptomycin, tetracycline and spectinomycin, but showed a high resistance up to mg/ml unit to heavy metals such as Ba, Li, Mn, AI, Cr and Pb. The optimal growth temperature of Acinetobactor sp. B2 was $30^{\circ}C.$ The lipase produced by Acinetobactor sp. B2 was purified by ammonium sulfate precipitation, DEAE-Toyopearl 650M ion exchange chromatography and Sephadex gel filtration chromatography. Its molecular mass was about 60 kDa and condition for the optimal activity was observed at $40^{\circ}C$ and pH 10, respectively. The activation energy of lipase for the hydrolysis of p­nitrophenyl palmitate was 2.7 kcal/mol in the temperature range of 4 to $37^{\circ}C,$ and the enzyme was unstable at the temperature higher than $60^{\circ}C.$ The Michaelis constant $(K_m)\;and\;V_{max}$ for p-nitrophenyl palmitate were 21.8 uM and $270.3\;{\mu}M\;min^{-1}mg^{-1},$ respectively. This enzyme was strongly inhibited by 10 mM $Cd^{2+},\;Co^{2+},\;Fe^{2+},\;Hg^{2+},$ EDTA and 2-Mercaptoethalol.

Precisely Nondestructive Diagnosis and Slope Stability of the Bonghwa Bukjiri Maaeyeoraejwasang (Rock-Carved Seated Buddha Statue), Korea (봉화 북지리마애여래좌상의 비파괴 정밀진단과 사면안정성 분석)

  • Cho, Ji-Hyun;Jo, Young-Hoon;Chun, Yu-Gun;Choi, Joon-Hyun;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.26 no.2
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    • pp.121-132
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    • 2010
  • The Bukjiri Maaeyeoraejwasang (National Treasure No. 201) consists of two-mica granite in medium size, which was the simbol of power in the region of the Silla period. Magnetic susceptibility of the host rock was measured as 0.41(${\times}10^{-3}$ SI unit), which has the similar range with surrounding outcrop. The Buddha developed parallel discontinuous plane of NE to SW strike and damaged seriously by exfoliation, granular disintegration and brown discoloration as 41.5%, 16.7% and 40.0%, respectively. As a result of the ultrasonic velocity, which was relatively weak values as 1,629m/s (Buddha area) and 1,549m/s (surrounding outcrop), improved about 900m/s compared to last treatment. From the results of the evaluation for slope stability, identified the possibility of toppling failure in the Buddha, and planar and wedge failure in host rock. Therefore, we suggest for the safely conservation of the Buddha, continuance monitoring for understand behavior of discontinuity system of the surface, and necessitate foundation reinforcement method for the rock which has the danger of collapse.

Business Ecosystem-focused Commercialization Strategy for Real-time Monitoring and Detection Technology for Landslides (실시간 산사태 모니터링 및 탐지기술에 대한 비즈니스 생태계 기반 기술사업화 전략 연구)

  • Sawng, Yeong-Wha;Lim, Dong-Hyun;Chae, Byung-Gon;Choi, Junghae
    • The Journal of Engineering Geology
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    • v.26 no.2
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    • pp.223-233
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    • 2016
  • This study establishes a commercialization strategy for technology that can monitor and detect landslides in real time. An effective commercialization strategy was sought through both qualitative and quantitative analyses. The qualitative analysis considered the business environment in detail, while the quantitative analysis examined technologically strong and weak areas by visualizing the links between IPC (International Patent Classification) code structure and patent applicants. The results from both analyses are considered together, with particular attention paid to the business environment. The resulting integrated analysis comprehensively explores the degree of technological development and the current state of real-time monitoring and detection technology for landslides. The integrated analysis identified complementary assets in the business environment, as there is strong development and many research entities in this area. This suggests positive reinforcement for commercialization with two sub-strategies: (1) exploring demand with complementary assets, and (2) providing technology information for explored demand, which should facilitate successful commercialization. Exploiting this positive reinforcement for technology commercialization could reduce the high uncertainty of the technology and the market, and thus increase the probability of successful commercialization. It is also expected to contribute to long-term success by strengthening collaboration between the supply and demand sides.

Immuno-Electron Microscopic Studies on the Localization of Serotonin and Somatostatin in the Optic Lobes of Cephalopods (Todarodes pacificus and Octopus minor) Inhabiting the Korean Waters (한국 연근해산 두족류 (Todarodes pacificus and Octopus minor) 시엽 (Optic lobe)내 Serotonin 및 Somatostatin의 분포에 관한 면역전자현미경적 연구)

  • Chang, Nam-Sub;Han, Jong-Min;Kim, Sang-Won;Lee, Kwang-Ju;Hwang, Sun-Jong;Lee, Jung-Chan
    • Applied Microscopy
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    • v.32 no.3
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    • pp.247-255
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    • 2002
  • In this study, we carried out immunostaining and immunogold labeling with antibodies to serotonin and somatostatin to examine the characteristics and functions of the neurons that secrete neurotransmitters in optic lobes of Todarodes pacificus and Octopus minor. As a result of immunostaining with anti-somatostatin, the nerve cells of Todarodes pacificus reacted as similar to the anti-serotonin, but in Octopus minor, only large cells in the outer granule cell layer reacted positively. In the immunogold labeling with anti-serotonin, the nerve cells in the inner grande cell layer and medulla of Todarodes pacificus reacted strongly, 30 gold particles being labeled per $0.5{\mu}m^2$ of the cytoplasm. However, in Octopus minor, only 17 gold particles were labeled, which stated a weak reaction. On the other hand, in the anti-somatostatin case, the nerve cells in the outer and inner granule cell layers and medulla of Todarodes pacificus showed strong reaction, 30 gold particles being labeled per $0.5{\mu}m^2$ of the cytoplasm while the nerve cells in the outer granule cell layer of Octopus minor reacted weakly, about 3 gold particles being labeled per the equivalent area. As a result of immunostaining and immunogold labeling with two types of antibodies to each part of the optic lobes, we found that the reactive nerve cells were distributed differently in the two species. In particular, the degree of reactivity to the immunostaining and immunogold labeling appeared stronger in Todarodes pacificus than in Octopus minor.

A Study on the High School Students' Perceptions of Soil Concepts (흙 개념에 대한 고등학생들의 인식 조사)

  • Hong, Jungjoo;Park, Shingyu;Park, Youn kwan;Kim, Jungwook;Chung, Wonwoo
    • Journal of Science Education
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    • v.34 no.1
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    • pp.93-104
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    • 2010
  • The purpose of this study was to investigate the high school students' interests and and perceptions about the soil concepts. The data were obtained from 72 boys and 82 girls at a high school in Daegu area. The questionnaires were developed 8 questions for students' interest and 10 questions for students' understanding. The results of this study were as follows. In the examination of students' interest on the soil concepts, boys showed 3.2point(64.9%) out of 5point and girls showed 3.2point(64.6%) out of 5 point. Furthermore, a percentage of correct answers for understanding on the soil concepts was 47.4%. In detail, Boys had 48.2% and girls had 46.6%, boys showed higher understanding about soil concepts than girls. And students understood soil concepts by a visible side, to approach the soil concepts from a biological point of view, rather than a geologic one. Also high school students didn't think soil concepts to consist of minerals and rocks from a geologic point of view. Correlation between interest and understanding on the soil concepts was very weak by showing r=.170(p<.05).

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Continuing Education for the Library and Information Professionals : Present Situation and Need Assessment (문헌정보전문직을 위한 계속교육에 관한 연구 : 현황과 요구분석)

  • Chang Hye-Rhan
    • Journal of the Korean Society for Library and Information Science
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    • v.31 no.1
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    • pp.7-28
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    • 1997
  • To investigate the present states and analyze the need of continuing education, a survey was done to the library and information professionals. Based on the personal membership file of the Korean Library Association, 292 members were selected using $25\%$ systematic sampling method. Questionnaires were mailed to them and $80\%$ returned. Of the total respondents. $90\%$ want to participate continuing education, however only $50\%$have a formal continuing education experience during last 3 years. Informal educational efforts are also weak and show much individual differences. $67\%$ of the libraries encourage continuing education but only $25\%$ of the respondents were provided with time and money for participation. The most favored mode of the continuing education Is one week course specialized In particular topic$(31.1\%)$ or area$(25.5\%)$. New methods, such as CD-ROM. online etc. were also preferred. Respondents regard professional association, society, and the library Information science department of university as desirable leading organization for continuing education. Among the 16 possible topics to be educated, respondents showed substantially higher Interest(more than $50\%$) In 5topics, and there were significant need differences In 7 topics among groups divided by library type.

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