• 제목/요약/키워드: University IT Research Center

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3차원 구조 소자에서의 doping profile에 따른 전류 특성 분석 (Analysis of Current Characteristics Determined by Doping Profiles in 3-Dimensional Devices)

  • 조성재;윤장근;박일한;이정훈;김두현;이길성;이종덕;박병국
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.475-476
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    • 2006
  • Recently, the demand for high density MOSFET arrays are increasing. In implementing 3-D devices to this end, it is inevitable to ion-implant vertically in order to avoid screening effects caused by high silicon fins. In this study, the dependency of drain current characteristics on doping profiles is investigated by 3-D numerical analysis. The position of concentration peak (PCP) and the doping gradient are varied to look into the effects on primary current characteristics. Through these analyses, criteria of ion-implantation for 3-D devices are established.

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Bisphenol A Bis(2,3-dihydroxypropyl) ether (BADGE.2H2O) Induces Orphan Nuclear Receptor Nur77 Gene Expression and Increases Steroidogenesis in Mouse Testicular Leydig Cells

  • Ahn, Seung-Won;Nedumaran, Balachandar;Xie, Yuanbin;Kim, Don-Kyu;Kim, Yong Deuk;Choi, Hueng-Sik
    • Molecules and Cells
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    • 제26권1호
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    • pp.74-80
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    • 2008
  • Bisphenol A bis (2,3-dihydroxypropyl) ether ($BADGE.2H_2O$) is a component of commercial liquid epoxy resins commonly used in the food-packing industry and in dental sealants. There is evidence that it has significant estrogenic activity. Nur77 plays a crucial role in the regulation of certain genes involved in LH-mediated steroidogenesis in testicular Leydig cells. It was previously demonstrated that Bisphenol A (BPA) stimulates Nur77 gene induction and steroidogenesis. In this study, we investigated the effects of $BADGE.2H_2O$ on Nur77 gene expression and steroidogenesis. Northern blot analysis showed that it increased the expression of Nur77 mRNA and protein, and transient transfection assays demonstrated that it increased the promoter activity and transactivation of Nur77. It also increased the expression of certain steroidogenic genes, such as StAR and $3{\beta}$-HSD. Finally, over-expression of a dominant negative Nur77 cDNA via adenoviral infection reduced $BADGE.2H_2O$-mediated progesterone biosynthesis. These results indicate that $BADGE.2H_2O$ disrupts testicular steroidogenesis by increasing Nur77 gene expression.

Hydrogen Generation by Electrical Discharge Through Metal / Water System

  • Park, Yong-Man;Kang, Goo-Jin;Cha, Suk-Yal;Lee, Woong-Moo
    • 에너지공학
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    • 제5권2호
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    • pp.198-202
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    • 1996
  • Reactive metals like aluminum generate hydrogen gas when it reacts with water. Aluminum, despite its high chemical affinity with water, cannot continue the reaction due to the passive oxide layers formed on its surface. When the reaction is assisted by electrical energy dissipation in the form of discharge, the reaction is more likely to be sustained. In this report, some preliminary experimental results are presented regarding the hydrogen generation based on this scheme.

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Measurement of Energy bands of the MgO Layer in AC-PDPs

  • Jeoung, S.J.;Lee, H.J.;Son, C.G.;Kim, J.H.;Park, E.Y.;Hong, Y.J.;You, N.L.;Lee, S.B.;Han, Y.G.;Jeoung, S.H.;Song, K.B.;Moon, M.W.;Oh, P.Y.;Choi, E.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.906-909
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    • 2006
  • The secondary electron emission coefficient $({\gamma})$ of the cathode is an important factor for improving the discharge characteristics of AC-PDPs because of its close relationship to discharge voltage. In AC-PDPs, MgO is most widely used as a surface protective layer. In this experimental, we have investigated the electronic structure of the energy band structure of the MgO layer responsible for the high ${\gamma}$. The MgO layers have been deposited by electron beam evaporation method, where the $O_2$ partial pressures have been varied as 0, $5.2{\times}10^{-5}$ torr, $1.0{\times}10^{-4}$ torr, and $4.1{\times}10^{-4}$ torr, in this experiment. It is noted that work function that is energy gap between surface and first defect level of MgO layer has the lowest value for the highest O2 partial pressure of $4.1^{\ast}10^{-4}$ Torr.

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Influence of the degradation of MgO protective layer on the Surface profiles and discharge characteristics in AC-PDP.

  • Lee, Soo-Beom;Jeoung, J.M.;Ko, B.D.;Oh, P.Y.;Moon, M.W.;Lee, J.H.;Lim, J.E.;Lee, H.J.;Han, Y.G.;Yoo, N.L.;Jeoung, S.H.;Son, C.G.;Choi, E.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1207-1210
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    • 2005
  • The MgO protective layer provides protection from the discharge, lowers the discharge voltage and prolongs the AC-PDP lifetime. We have investigated the characteristics of degradation of MgO protective layer, which correlates to the image-sticking[1] and the lifetime in AC-PDP. The degraded MgO have been changed the surface morphology of MgO. It was found that panel lifetime depended on degradation of MgO protective.

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A study of characteristics for Image sticking in AC - Plasma Display Panel

  • Han, Yong-gyu;Lee, S.B.;Jeong, S.H.;Son, C.G.;Yoo, N.L.;Lee, H.J.;Lim, J.E.;Lee, J.H.;Jeoung, J.M.;Ko, B.D.;Oh, P.Y.;Moon, M.W.;Choi, Eun-Ha
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.263-265
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    • 2005
  • In the alternative current plasma display panel(AC-PDP) technology, it is very important to remove the image sticking for improving an image quality. In this paper, we have investigated the driving method of alternative current plasma display panel(AC-PDP) for preventing image sticking. We have investigated the driving method of alternative current plasma display panel(AC-PDP) for preventing image sticking. The preventing method of image sticking was proposed by adopting the Sticking Remove Pulse(SRP). The variation of brightness is most affected by the MgO to be formed at the surface of the phosphor layer. As a result, the image sticking is reduced when the driving method adopted an SRP.

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Morphology and Surface Magnetism of Ultrathin Fe Films on Pd(111)

  • Park, Jae-Hoon;Kim, Wookje;Kim, Wondong;Kim, Jae-Young;Hoon Koh;S.J. Oh
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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    • pp.141-141
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    • 2000
  • In situ surface magneto-optic Kerr effect(SMOKE), X-ray photoelectron spectroscopy(XPS) and low energy electron diffraction(LEED) were used to study magnetic and structural properties of ultrathin Fe films grown on the Pd(111) surface. The SMOKE measurement showed strong enhancement of ferromagnetism after proper annealing process. Simultaneous changes in morphology was checked by LEED and XPS. After room temperature Fe deposition. longitudinal magnetization appeared above a critical thickness between 2.0 and 2.5 monolayers. When annealed at 450K, 2.0 monolayer Fe film exhibited boty longitudinal and polar magnetizations while 3.0 and 5.5 monolayer films showed little changes. After annealing at 600K, both magnetizations were totally destroyed in 2.0 monolayer film, but longitudinal magnetization was enhanced in 3.0 monolayer film. In the case of 5.5 monolayer film, it was only after 660K annealing that the enhancement of the longitudinal magnetization was observed. It was concluded that the surface flatness and the amount of intermixing were critical in the development of surface magnetism of this system.

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A Registry Program for Familial Gastric Cancer Patients Referred to Cancer Institute of Iran

  • Etemadi, Mehrnoosh;Pourian, Mandana;Shakib, Asyeh;Sabokbar, Tayebeh;Peyghanbari, Vahideh;Shirkoohi, Reza
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권5호
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    • pp.2141-2144
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    • 2014
  • Background: Gastric cancer is the second most common cause of cancer death. It has a poor prognosis with only 5-10% of hereditary etiology. If it is diagnosed, it could be helpful for screening the other susceptible members of a family for preventive procedures. Usually it is identified by symptoms such as presence of cancer in different members of family, some special type of pathology such as diffused adenocarcinoma, having younger age and multiple cancer syndromes. Hence, designing a registry program can be a more practical way to screen high risk families for a preventive program. Materials and Methods: Based on the inclusion criteria, a questionnaire was prepared. After pilot on a small number of patients, the actual data was collected from 197 patients and processed in SPSS 16.0. Results: Totally, 11.8% of the patients were younger than 45 years old. Blood type 'A' was dominant and males had a higher risk behavior with higher consumption of unhealthy food. Adenocarcinoma was reported in majority of cases. 21.8% of the patients had the including criteria for familial gastric cancer (FGC). Conclusions: The high percentage of FGC population compared to the other studies have revealed a need to design an infrastructural diagnostic protocol and screening program for patients with FGC, plus preventive program for family members at risk which could be done by a precise survey related to frequency and founder mutations of FGC in a national registry program.

Numerical Identification of a Streptomyces Strain Producing Spores in Submerged Culture

  • Rho, Yong-Taik;Kim, Hyoung-Tae;Oh, Kyoung-Hee;Kang, Heui-Il;Alan C. Ward;Michael Goodfellow;Hah, Yung-Chil;Lee, Kye-Joon
    • 미생물학회지
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    • 제30권4호
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    • pp.278-285
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    • 1992
  • Chemotaxonomic and numerical identification were carried out for a isolate of Streptomyces strain SMF301 producing spores in submerged culture. Fifty taxonomic unit characters were tested and the data were analyzed numerically using the TAXON program. The isolate SMF301 was identified to cluster 1A of Streptomyces and best matched to Streptomyces limosus which is a synonym of Streptomyces albidoflavus. Therefore, it was concluded that the isolate was identified to be a member of Streptomyces alidoflavus.

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Development of a New Type of Recombinant Hyaluronidase Using a Hexahistidine; Possibilities and Challenges in Commercialization

  • Park, Chaeri;Song, Yun-Kyoung;Kim, Young-Hyun;Jung, Yena;Park, Young-Ho;Song, Bong-Seok;Eom, Taekil;Kim, Ju-Sung;Kim, Sang-Hyun;Kim, Ji-Su;Kim, Sun-Uk;Lee, Sang-Rae;Kim, Ekyune
    • Journal of Microbiology and Biotechnology
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    • 제29권8호
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    • pp.1310-1315
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    • 2019
  • Hyaluronidases enhance therapeutic drug transport by breaking down the hyaluronan barrier to lymphatic and capillary vessels, facilitating their tissue absorption. Commercially available hyaluronidases are bovine in origin; however, they pose risks such as bovine spongiform encephalopathy. The present study aimed to develop a novel, highly active hyaluronidase and assess its function. Therefore, in order to find the most efficient active hyaluronidase, we produced several shortened hyaluronidases with partial removal of the N- or C-terminal regions. Moreover, we created an enzyme that connected six histidines onto the end of the hyaluronidase C-terminus. This simplified subsequent purification using $Ni^{2+}$ affinity chromatography, making it feasible to industrialize this highly active recombinant hyaluronidase which exhibited catalytic activity equal to that of the commercial enzyme. Therefore, this simple and effective isolation method could increase the availability of recombinant hyaluronidase for research and clinical purposes.