• Title/Summary/Keyword: research structure

Search Result 24,037, Processing Time 0.052 seconds

Tertiary Structure of PreSl(21-47) of Hepatitis B Virus Studied by NMR Spectroscopy

  • Kyeunghee Yu;Cho, Eun-Wie;Shin, Song-Yub;Kim, Kol-Lyong;Kim, Yangmee
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.4 no.1
    • /
    • pp.41-49
    • /
    • 2000
  • To design more efficient peptide antagonist against the HBV, preSl(21-47) which carries the HBV receptor binding site for hepatocytes was synthesized and the solution structure of preSl(21-47) was investigated using CD spectroscopy and NMR spectroscopy in membrane-mimicking environments. According to CD spectra, preSl(21-47) has a random structure in aqueous solution, while conformational change was induced by addition of TFE and SDS micelle. Tertiary structures as determined by NMR spectroscopy shows that preSl(21-47) has a very flexible structure even in SDS micelle.

  • PDF

EFFECT OF METAL CONTACT ON THE CZT DETECTOR PERFORMANCE

  • Park, Se-Hwan;Park, Hyung-Sik;Lee, Jae-Hyung;Kin, Han-Soo;Ha, Jang-Ho
    • Journal of Radiation Protection and Research
    • /
    • v.34 no.2
    • /
    • pp.65-68
    • /
    • 2009
  • Metal-semiconductor contact is very important for the operating property of semiconductor detector. $Cd_{0.96}$ $Zn_{0.04}$ Te semiconductor crystal was grown with Bridgman method, and the crystal was cut and polished. EPMA (Electron Probe Micro Analyzer) and ICP-MS (Inductively Coupled Plasma Mass Spectrometry) analysis were done to obtain the chemical composition and impurity of the crystal. Metal contact was deposited with thermal evaporator on both sides of the crystal. Detectors with Au/CZT/Au and In/CZT/Au structure were made, and I-V curve and the energy spectrum were measured with the detectors. It could be seen that the detector with the In/CZT/Au structure has superior property than the detector with Au/CZT/Au structure when the crystal resistivity was low. However, the metal contact structure effect becomes low when the crystal resistivity was high.

Development of Manufacturing Technology for Milli-Structure (Milli-Structure 생산기술개발)

  • 나경환;박훈재;조남선
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2000.05a
    • /
    • pp.1039-1042
    • /
    • 2000
  • This research will deal with Innovative manufacturing technology for milli-structure manufacturing technology which is located betweon the traditional manufacturing technology for macro-sized structure and the recently emerging manufacturing technology for micro-scaled structure such as MEMS. There are four fields in this research, which are micro-sheet metal forming technology, micro-bulk forming technology micro-molding technology and micro die making technology. As a project for new-technology in next generation, this research will be carried out through three terms and each term and be composed of three years.

  • PDF

A Case Research of Application of Submarine Structure for Discharge in the Power Plants (발전소 해양 배수 구조물의 적용사례)

  • Park, See-Boum;Bae, Dong-Chan
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.10a
    • /
    • pp.1689-1692
    • /
    • 2008
  • In this research, these days extension of electric power station plant and new building plan is tending to more bigger size and much more cooling water for discharge, therefore submarine structure for discharge has needed various types and the large one. The domestic power plant was applied to once-through CW system structure that pipe line type, immersed PC-box culvert type and submarine headrace tunnel type of discharge structure. It is possible that the future structure type of submarine discharge is expected by a case research of application and plan.

  • PDF

Key Technologies for Floating Type Artificial Upwelling System to Strengthen Primary Production (해역 기초생산력 증대를 위한 부유식 인공용승시스템 요소기술)

  • Jung, Dong-Ho;Lee, Ho-Saeng;Kim, Hyeon-Ju;Moon, Deok-Soo;Lee, Seung-Won
    • Journal of Ocean Engineering and Technology
    • /
    • v.26 no.1
    • /
    • pp.78-83
    • /
    • 2012
  • The abundant nutrients contained in deep seawater are delivered by natural upwellings from the deep sea to the surface sea. However, the natural upwelling phenomenon is limited to specific areas of the sea; in other areas, the thermocline separates the surface sea from the lower layer. Thus, the surface layer is often deficient in nutritive salts, causing the deterioration of its primary productivity and ultimately leading to an imbalance in the marine ecosystem. Without a consistent supply of nitrogenous nutritive salts, they are absorbed by phytoplankton, resulting in a considerable problem in primary productivity. To solve this issue, a floating type of artificial upwelling system is suggested to artificially pump up, distribute, and diffuse deep seawater containing rich nutritive salts. The key technologies for developing such a floating artificial upwelling system are a floating offshore structure with a large diameter riser, self-supplying energy system, density current generating system, method for estimating the emission and absorption of CO2, and way to evaluate the primary production variation. Strengthening the primary production of the sea by supplying deep seawater to the sea surface will result in a sea environment with abundant fishery resources.

Structural and Biochemical Characterization of the Two Drosophila Low Molecular Weight-Protein Tyrosine Phosphatases DARP and Primo-1

  • Lee, Hye Seon;Mo, Yeajin;Shin, Ho-Chul;Kim, Seung Jun;Ku, Bonsu
    • Molecules and Cells
    • /
    • v.43 no.12
    • /
    • pp.1035-1045
    • /
    • 2020
  • The Drosophila genome contains four low molecular weight-protein tyrosine phosphatase (LMW-PTP) members: Primo-1, Primo-2, CG14297, and CG31469. The lack of intensive biochemical analysis has limited our understanding of these proteins. Primo-1 and CG31469 were previously classified as pseudophosphatases, but CG31469 was also suggested to be a putative protein arginine phosphatase. Herein, we present the crystal structures of CG31469 and Primo-1, which are the first Drosophila LMW-PTP structures. Structural analysis showed that the two proteins adopt the typical LMW-PTP fold and have a canonically arranged P-loop. Intriguingly, while Primo-1 is presumed to be a canonical LMW-PTP, CG31469 is unique as it contains a threonine residue at the fifth position of the P-loop motif instead of highly conserved isoleucine and a characteristically narrow active site pocket, which should facilitate the accommodation of phosphoarginine. Subsequent biochemical analysis revealed that Primo-1 and CG31469 are enzymatically active on phosphotyrosine and phosphoarginine, respectively, refuting their classification as pseudophosphatases. Collectively, we provide structural and biochemical data on two Drosophila proteins: Primo-1, the canonical LMW-PTP protein, and CG31469, the first investigated eukaryotic protein arginine phosphatase. We named CG31469 as DARP, which stands for Drosophila ARginine Phosphatase.

Correlation between optimized thicknesses of capping layer and thin metal electrode for efficient top-emitting blue organic light-emitting diodes

  • Hyunsu Cho;Chul Woong Joo;Byoung-Hwa Kwon;Chan-mo Kang;Sukyung Choi;Jin Wook Sin
    • ETRI Journal
    • /
    • v.45 no.6
    • /
    • pp.1056-1064
    • /
    • 2023
  • The optical properties of the materials composing organic light-emitting diodes (OLEDs) are considered when designing the optical structure of OLEDs. Optical design is related to the optical properties, such as the efficiency, emission spectra, and color coordinates of OLED devices because of the microcavity effect in top-emitting OLEDs. In this study, the properties of top-emitting blue OLEDs were optimized by adjusting the thicknesses of the thin metal layer and capping layer (CPL). Deep blue emission was achieved in an OLED structure with a second cavity length, even when the transmittance of the thin metal layer was high. The thin metal film thickness ranges applicable to OLEDs with a second microcavity structure are wide. Instead, the thickness of the thin metal layer determines the optimized thickness of the CPL for high efficiency. A thinner metal layer means that higher efficiency can be obtained in OLED devices with a second microcavity structure. In addition, OLEDs with a thinner metal layer showed less color change as a function of the viewing angle.

Double-stranded RNA Induces Inflammatory Gene Expression in Schwann Cells: Implication in the Wallerian Degeneration

  • Lee, Hyun-Kyoung;Park, Chan-Hee;Choi, Se-Young;Oh, Seog-Bae;Park, Kyung-Pyo;Kim, Joong-Soo;Lee, Sung-Joong
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.8 no.5
    • /
    • pp.253-257
    • /
    • 2004
  • Schwann cells play an important role in peripheral nerve regeneration. Upon neuronal injury, activated Schwann cells clean up the myelin debris by phagocytosis, and promote neuronal survival and axon outgrowth by secreting various neurotrophic factors. However, it is unclear how the nerve injury induces Schwann cell activation. Recently, it was reported that certain cytoplasmic molecules, which are secreted by cells undergoing necrotic cell death, induce immune cell activation via the toll-like receptors (TLRs). This suggests that the TLRs expressed on Schwann cells may recognize nerve damage by binding to the endogenous ligands secreted by the damaged nerve, thereby inducing Schwann cell activation. Accordingly, this study was undertaken to examine the expression and the function of the TLRs on primary Schwann cells and iSC, a rat Schwann cell line. The transcripts of TLR2, 3, 4, and 9 were detected on the primary Schwann cells as well as on iSC. The stimulation of iSC with poly (I : C), a synthetic ligand for the TLR3, induced the expression of $TNF-{\alpha}$ and RANTES. In addition, poly (I : C) stimulation induced the iNOS expression and nitric oxide secretion in iSC. These results suggest that the TLRs may be involved in the inflammatory activation of Schwann cells, which is observed during Wallerian degeneration after a peripheral nerve injury.

Analyzing the Sentence Structure for Automatic Identification of Metadata Elements based on the Logical Semantic Structure of Research Articles (연구 논문의 의미 구조 기반 메타데이터 항목의 자동 식별 처리를 위한 문장 구조 분석)

  • Song, Min-Sun
    • Journal of the Korean Society for information Management
    • /
    • v.35 no.3
    • /
    • pp.101-121
    • /
    • 2018
  • This study proposes the analysis method in sentence semantics that can be automatically identified and processed as appropriate items in the system according to the composition of the sentences contained in the data corresponding to the logical semantic structure metadata of the research papers. In order to achieve the purpose, the structure of sentences corresponding to 'Research Objectives' and 'Research Outcomes' among the semantic structure metadata was analyzed based on the number of words, the link word types, the role of many-appeared words in sentences, and the end types of a word. As a result of this study, the number of words in the sentences was 38 in 'Research Objectives' and 212 in 'Research Outcomes'. The link word types in 'Research Objectives' were occurred in the order such as Causality, Sequence, Equivalence, In-other-word/Summary relation, and the link word types in 'Research Outcomes' were appeared in the order such as Causality, Equivalence, Sequence, In-other-word/Summary relation. Analysis target words like '역할(Role)', '요인(Factor)' and '관계(Relation)' played a similar role in both purpose and result part, but the role of '연구(Study)' was little different. Finally, the verb endings in sentences were appeared many times such as '~고자', '~였다' in 'Research Objectives', and '~었다', '~있다', '~였다' in 'Research Outcomes'. This study is significant as a fundamental research that can be utilized to automatically identify and input the metadata element reflecting the common logical semantics of research papers in order to support researchers' scholarly sensemaking.

Effect of Silane and Sulfur Variation on the Vulcanizate Structure of Silica-Filled Styrene-Butadiene Rubber Compounds

  • Han, Sangwook;Kim, Donghyuk;Kim, Seongrae;Kim, Jongmyoung;Mun, Dalyong;Morita, Koichi;Kim, Wonho
    • Elastomers and Composites
    • /
    • v.56 no.1
    • /
    • pp.32-42
    • /
    • 2021
  • The vulcanizate structure of silica-filled compounds is affected by the filler-rubber interaction (FRI) due to the silica-rubber coupling reaction and the chemical crosslink density (CCD) of the matrix rubber. In this study, the vulcanizate structure changes of silica-filled compounds according to the silane and sulfur variation were quantitatively analyzed using the Flory-Rehner and Kraus equations. In efficiency vulcanization (EV) conditions with low sulfur content, FRI increased when the bis-[3-(triethoxysilyl)propyl]tetrasulfide (TESPT) content increased, and the CCD clearly decreased. By contrast, in semi-EV conditions with high sulfur content, as TESPT content increased, the FRI increased the same way EV conditions, but the CCD was unchanged. Based on these results, it was confirmed that FRI of the silica-filled compounds increased as TESPT content increased, but CCD decreased or retained similar values according to the vulcanization system, indicating that the formation reaction of FRI was preferred over CCD.