• 제목/요약/키워드: Helix 8

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Podcasting and Politics in Singapore: An Experimental Study of Medium Effects

  • Skoric, Marko M.;Sim, Clarice;Juan, Han Teck;Fang, Pam
    • Journal of Contemporary Eastern Asia
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    • 제8권2호
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    • pp.27-43
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    • 2009
  • A ban on political podcasting during the General Elections 2006 in Singapore was justified by the Singaporean government on the grounds that the new medium had a greater power to influence voters than traditional modes of political discourse. A between-subjects controlled experiment was conducted to test whether podcasts of political speeches had a greater power to influence voters' evaluations of political candidates and likelihood of voting for them than online text-based transcripts of the same speeches. The study also examined whether mere exposure to political speeches online, irrespective of the modality, had an effect on voters' more general political preferences, i.e. the likelihood of support and voting for the opposition. The findings suggest that political podcasts were no more persuasive than text-based websites and that the effects on political preferences, if any, were likely due the exposure to political content online, not because of the nature of the medium. The implications of the findings are discussed.

Satellite-Digital Multimedia Broadcasting 단말기용 헤리컬 안테나 설계 (Design of Quadrifilar Helical Antenna for the Satellite-Digital Multimedia Broadcasting Terminal)

  • 이강훈;박주남;이영철
    • 한국전자통신학회논문지
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    • 제4권1호
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    • pp.46-52
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    • 2009
  • 위성-DMB 영상신호를 수신하는 헤리컬 안테나를 설계하였다. 위성-DMB용 헤리컬 안테나의 위상이 0, 90, 180, 270도 급전 되도록 4중실선(Quadrifilar) 형태로 설계함으로서 원형 편파의 특성을 나타내었으며 QHA 안테나의 상단 갭 간격, 턴 수 및 높이를 가변시켜 최적화시켰다. 최종 설계치는 갭 a=2.2mm, Helix 턴 수 b=0.9 턴 및 길이 c=42mm 이고 입력반사 계수는 주파수 2.62GHz에서 약 -5.8dB 정도이며, 상반평면 방사특성과 0.508dB의 축비특성을 나타내었다. 설계된 이중대역 QHA는 위성-DMB 수신 안테나에 적용되고 있다.

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Structure of CT26 in the C-terminal of Amyloid Precursor Protein Studied by NMR Spectroscopy

  • Kang, Dong-Il;Baek, Dong-Ha;Shin, Song-Yub;Kim, Yang-Mee
    • Bulletin of the Korean Chemical Society
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    • 제26권8호
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    • pp.1225-1228
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    • 2005
  • C-terminal fragments of APP (APP-CTs), that contain A$\beta$ sequence, are found in neurotic plaques, neurofibrillary tangles and the cytosol of lymphoblastoid cells obtained from AD patients. CT26, Thr639-Asp664 (TVIVITLVMLKKKQYTSIHH GVVEVD) includes not only the transmembrane domain but also the cytoplasmic domain of APP. This sequence is produced from cleavage of APP by caspase and $\gamma$-secretase. In this study, the solution structure of CT26 was investigated using NMR spectroscopy and circular dichroism (CD) spectropolarimeter in various membrane-mimicking environments. According to CD spectra and the tertiary structure of CT26 determined in TFE-containing aqueous solution, CT26 has an α-helical structure from $Val^{2}\;to\;Lys^{11}$ in TFE-containing aqueous solution. However, according to CD data, CT26 adopts a $\beta$-sheet structure in the SDS micelles and DPC micelles. This result implies that CT26 may have a conformational transition between $\alpha$-helix and $\beta$-sheet structure. This study may provide an insight into the conformational basis of the pathological activity of the C-terminal fragments of APP in the model membrane.

The High Resolution NMR Solution Structure of Monocyte Chemoattractant Protein-3

  • Kwon Do-Yoon;Lee Duck-Yeon;Sykes Brian D.;Kim Key-Sun
    • 한국자기공명학회논문지
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    • 제9권2호
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    • pp.74-92
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    • 2005
  • The high resolution solution structure of MCP-3 was determined using multinuclear, multidimensional NMR spectroscopy with an expressed and $^{13}C-\;and\;^{15}N-labeled$ protein. The MCP-3 has a typical chemokine fold including 3 anti-parallel $\beta-sheets$, and a C-terminal helix, but it exists as a monomer in solution under the conditions where the structure was determined (2 mM, pH 5.1 at $30^{\circ}C$). Based on the structure and the amino acid sequence compared to other chemokines we propose that Ile20 and Leu25 in MCP-3 play key roles in the formation of N-loop (residues between the $2^{nd}$ cysteine and the I sheet) which has been implicated as a determinant of chemokine specificity. Additional receptor binding surface is supplied by the 40s loop (residues between the 2 and the 3 sheet) and the binding interface of the acidic N-terminal region of chemokine receptor to MCP-3 would resemble the dimerization interface of CC type dimer.

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Strategic Management of Universities for Regional Competitiveness

  • NURMUKHANOVA, Gulnara;ALIBEKOVA, Gulnaz;TAMENOVA, Saltanat;NIYETALINA, Gaukhar
    • The Journal of Asian Finance, Economics and Business
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    • 제8권1호
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    • pp.551-562
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    • 2021
  • Strategic management of universities is crucial for the regional competitiveness due to the high impact of universities on the economic growth of regions through entrepreneurial training and support. The study aimed to investigate the HEInnovate self-assessment tool, valuable in building entrepreneurship-oriented strategy, by considering the case of Turan University. The tool can be used to study entrepreneurial capabilities of the university and make strong management decisions. The self-assessment allows getting feedback from all stakeholders, including external ones, which helps to make institutional changes to influence the regional economic growth. The framework of the research is based on the theories of strategic management and regional competitiveness, which can be deployed with the HEInnovate self-assessment recommendations and findings. The research methodology comprises objective and functional approaches to system analysis. HEInnovate self-assessment by Turan university revealed some weaknesses in the university strategy and helped make some recommendations, namely, the university's entrepreneurial ecosystem must act as part of a regional business support ecosystem to provide input into local economic development, attract more international faculty and faculty with more practical experience, create an entrepreneurial culture across staff of the university, address a lack of internal structures to support staff, and improve university-business cooperation.

누에에서 새로운 항세균성 펩타이드 유사 유전자의 분리와 염기서열 결정 (Molecular Cloning of a Gene Encoding a Putative Antibacterial Peptide from Bombyx mori)

  • 김상현;제연호;윤은영;강석우;김근영;강석권
    • 한국응용곤충학회지
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    • 제35권4호
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    • pp.321-325
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    • 1996
  • 누에에서 새로운 항세균성 펩타이드 유전자를 탐색하기 위하여 E. coli K12로 체강 주사한 누에 유충의 cDNA 유전자 은행에서 차별화 선별로, 잠재 항세균성 펩타이드 유전자로 추정되는 BmInc8 클론을 분리하였다. BmInc8은 564bp의 크기를 가지며, 59개 아미노산을 coding하는 open reading frame과 2개의 잠정 폴리아데닐화 부위를 보유하고 있었다. BmInc8은 M. sexta에서 분리, 보고된 bactericidine 유전자와 61.2%의 DNA 상동성을 나타내는 것으로, 그 연역된 펩타이드 구조는 항세균성 펩타이드의 일종인 cecropin과 유사한 2가닥의 $\alpha$-helix가 Lysine-Proline 경첩부위에 의해 포개져 있는 형태를 갖는 것으로 추정되었다. 또한 cDNA 삽입 부위의 기능성 검정을 위해 원핵 발현벡터인 pT7-5를 이용하여 E. coli BL21(DE3) 균주에 형질전환하고 IPTG로 induction한 결과 E. coli BL21(DE3) 균주의 성장이 정지됨을 관찰할 수 있었다. 이상의 결과로 BmInc8은 DNA 상동성 비교, 연역 아미노산의 구조 추정 및 cDNA 삽입 부위를 이용한 transient expression 결과 항세균성 펩타이드를 coding하는 유전자임을 추정할 수 있었다. 또한 Bminc8의 cDNA 유전자 정보를 GenBank에 등록하였으며 등록 번호는 U30289이었다.

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사철느타리버섯 중 $G_{418}$-sensitive 미토콘드리아성 ATPase/ATP synthase의 특성 (Characteristics of $G_{418}$-sensitive mitochondrial ATPase/ATP synthase from pleurotus florida)

  • 김재웅;김동희;이정복;이서구;민태진
    • 분석과학
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    • 제5권4호
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    • pp.477-484
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    • 1992
  • 형질 전환된 사철느타리버섯으로부터 초원심분리 및 설탕밀도 기울기법으로 44% 층에서 미토콘드리아를 분리정제하였다. ATPase와 ATP synthase의 최적 활성조건은 각각 pH 7.4, $60^{\circ}C$ 및 pH 7.5, $57^{\circ}C$였고, km값은 11.6mM과 8.4mM였다. ATPase는 기질농도 5~6mM의 ATP에서, ATP synthase는 5~10mM ADP 농도에서 활성이 높으며, 그 이상의 농도에서는 기질 저해를 받았다. ATPase/ATP synthase 모두 $Mg^{2+}$ 의존성 효소로 $G_{418}$으로 비경쟁적인 저해를 받았다. 효소의 아미노산 분석결과 hydrophobic 아미노산 잔기는 50.5%, small 아미노산 잔기는 56.1%, hydrogen bonding 아미노산 잔기는 43.7%, helix breaking 아미노산 잔기는 55.2%였다. 인지질을 분석한 결과 phosphatidyl glycerol, phosphatidyl choline 및 phosphatidyl ethanolamine으로 구성되었고 phosphatidyl serine과 phosphatidyl inositol은 전혀 없었다. 포화 지방산은 palmitate(51.31%)와 stearate(18.32%)의 함량이 많았고, 불포화 지방산($C_{18:1}$, $C_{18:2}$$C_{16:1}$)의 함량도 많았다.

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질소처리에 따른 여러 관엽식물의 생육반응 (Growth Responses of Various Ornamental Foliage Plants According to the Amount of Nitrogen Application)

  • 심명선;길미정
    • 생물환경조절학회지
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    • 제21권4호
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    • pp.485-490
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    • 2012
  • 질소처리에 따른 여러 관엽식물의 생육반응 및 엽내 질소 함량을 구명하여 초기 생육을 단축시키고 관엽식물의 영양관리에 있어 기초자료를 제시하고자 하였다. 실험재료로 벤자민고무나무, 관음죽, 필로덴드론, 스파티필럼, 아이비 등 많이 이용되고 있는 관엽식물들을 선택하였다. 화분에 식재한 관엽식물에 질소량을 각각 120, 150, 180, $210mg{\cdot}L^{-1}$로 처리하고, 8주 후 식물의 초장, 폭, 엽수, 엽면적, 생체중 및 건물중 등을 측정하였다. 식물 부위별 질소 함량도 분석하였다. 벤자민고무나무와 아이비는 N1 처리에서 식물의 생육이 우수하고, 초장 및 엽수의 증가량이 가장 큰 것으로 나타났다. 필로덴드론과 관음죽은 N4 처리의 경우 식물 생육이 일부 향상되었으나, 초장 및 엽수의 증가량은 다른 질소수준들간에 큰 차이는 없었다. 특히 관음죽은 식물의 생장량이 거의 없었다. 스파티필럼은 N4 처리에서 식물의 생육이 우수하고, 초장 및 엽수의 증가량도 가장 큰 것으로 보여졌다. 각 식물별 적합한 질소수준이 다른 것으로 판단되었다. 질소수준별 처리가 엽록소 함량에 크게 영향을 주지 않았고, 식물 부위별 질소함량도 일관된 경향을 보여지지 않았다. 그러므로, 관엽식물에서는 잎 등 식물체 부위별 영양 상태보다 식물의 생육반응으로 영양상태를 진단하는 것이 더 적합한 것으로 판단되었다.

The Role of Residues 103, 104, and 278 in the Activity of SMG1 Lipase from Malassezia globosa: A Site-Directed Mutagenesis Study

  • Lan, Dongming;Wang, Qian;Popowicz, Grzegorz Maria;Yang, Bo;Tang, Qingyun;Wang, Yonghua
    • Journal of Microbiology and Biotechnology
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    • 제25권11호
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    • pp.1827-1834
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    • 2015
  • The SMG1 lipase from Malassezia globosa is a newly found mono- and diacylglycerol (DAG) lipase that has a unique lid in the loop conformation that differs from the common alpha-helix lid. In the present study, we characterized the contribution of three residues, L103 and F104 in the lid and F278 in the rim of the binding site groove, on the function of SMG1 lipase. Site-directed mutagenesis was conducted at these sites, and each of the mutants was expressed in the yeast Pichia pastoris, purified, and characterized for their activity toward DAG and p-nitrophenol (pNP) ester. Compared with wild-type SMG1, F278A retained approximately 78% of its activity toward DAG, but only 11% activity toward pNP octanoate (pNP-C8). L103G increased its activity on pNP-C8 by approximately 2-fold, whereas F104G showed an approximate 40% decrease in pNP-C8 activity, and they both showed decreased activity on the DAG emulsion. The deletion of 103-104 retained approximately 30% of its activity toward the DAG emulsion, with an almost complete loss of pNP-C8 activity. The deletion of 103-104 showed a weaker penetration ability to a soybean phosphocholine monolayer than wild-type SMG1. Based on the modulation of the specificity and activity observed, a pNP-C8 binding model for the ester (pNP-C8, N102, and F278 form a flexible bridge) and a specific lipid-anchoring mechanism for DAG (L103 and F104 serve as "anchors" to the lipid interface) were proposed.

Functional characterization of the distal long arm of laminin: Characterization of Cell- and heparin binding activities

  • Sung, Uhna;O′Rear, Julian J.;Yurchenco, Peter D.
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1995년도 제3회 추계심포지움
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    • pp.107-113
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    • 1995
  • Basement membrane laminin is a multidomain glycoprotein that interacts with itself, heparin and cells. The distal long arm plays major cell and heparin interactive roles. The long arm consists of three subunits (A, B1, B2) joined in a coiled-coil rod attached to a terminal A chain globule (G). The globule is in turn subdivided into five subdomains (Gl-5). In order to analyze the functions of this region, recombinant G domains (rG, rAiG, rG5, rGΔ2980-3028) were expressed in Sf9 insect cells using a baculovirus expression vector. A hybrid molecule (B-rAiG), consisting of recombinant A chain(rAiG) and the authentic B chains (E8-B)was assembled in vitro. The intercalation of rAiG into E8-B chains suppressed a heparin binding activity identified in subdomain Gl-2. By the peptide napping and ligand blotting, the relative affinity of each subeomain to heparin was assigned as Gl> G2= G4> G5> G3, such that G1 bound strongly and G3 not at all. The active heparin binding site of G domain in intact laminin appears to be located in G4 and proximal G5. Cell binding was examined using fibrosarcoma Cells. Cells adhered to E8, B-rAiG, rAiG and rG, did not bind on denatured substrates, poorly bound to the mixture of E8-B and rG. Anti-${\alpha}$6 and anti-${\beta}$1 integrin subunit separately blocked cell adhesion on E8 and B-rAiG, but not on rAiG. Heparin inhibited cell adhesion on rAiG, partially on B-rAiG, and not on E8. In conclusion, 1) There are active and cryptic cell and heparin binding activities in G domain. 2) Triple-helix assembly inactivates cell and heparin binding activities and restores u6131 dependent cell binding activities.

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