• 제목/요약/키워드: helix F

검색결과 33건 처리시간 0.026초

Structural Studies on the E. coli Methionyl-tRNA Synthetase and Their Interaction with E. coli $tRNA^{fMet}$

  • Kim Ji-Hun;Ahn Hee-Chul;Park Sung-Jin;Kim Sung-Hoon;Lee Bong-Jin
    • 한국자기공명학회논문지
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    • 제9권2호
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    • pp.110-121
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    • 2005
  • E.coli methionyl tRNA synthetase consist of 676 amino acids and plays a key role in initiation of protein synthesis. The native form of this enzyme is a homodimer, but the monomeric enzyme truncated approximately C-terminal 120 amino acids retains the full enzymatic activities. X-ray crystal structure of the active monomeric enzyme shows that it has two domains. The N-terminal domain is thought to be a binding site for acceptor stem of tRNA, ATP, and methionine. The C-terminal domain is mainly a-helical and makes an interaction with the anticodon of $tRNA^{Met}$. Especially it is suggested that the region of helix-loop-helix including the tryptophan residue at the position 461 may be the essential for the interaction with anticodon of $tRNA^{Met}$. In this work the structure and function of E. coli methionyl-tRNA synthetase was studied by spectroscopic method (NMR, CD, Fluorescence). The importance of tryptophan residue at the position 461 was investigated by fluorescence spectroscopy. Tryptophan 461 is expected to be an essential site for the interaction between E. coli methionyl-tRNA synthetase and E. coli $tRNA^{Met}$. Proton and heteonuclear 2-dimensional NMR spectroscopy were also used to elucidate the protein-tRNA interaction.

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Harmony through Holistic Engagement: An Emic Model of Greater East Asian Regionalism

  • von Feigenblatt, Otto F.
    • Journal of Contemporary Eastern Asia
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    • 제12권2호
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    • pp.61-87
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    • 2013
  • This study applies grounded theory to develop an emic substantive theory of regional integration in Greater East Asia. The role of norms and policies is explored through discursive content analysis of a wide theoretical sample of official elite policy statements dealing with regionalism and related policy areas. A resulting model of regional integration titled "Harmony through Holistic Engagement" is then discussed in relation to the etic consensus on the phenomenon. The study concludes that the etic consensus on the nature of regional integration in Greater East Asia greatly differs from the results of an emic approach and thus reflects a normative consensus rather than a descriptive reality.

The Empire of Japan’s Foreign Policy

  • Feigenblatt, Otto F. von
    • Journal of Contemporary Eastern Asia
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    • 제15권1호
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    • pp.17-26
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    • 2016
  • The present research applies the Theory of Harmony through Holistic Engagement to the foreign policy of Japan. As the third largest economy in the world and one of the most highly developed countries in the world, Japan is a major international power. Most analysts interpret Japan’s foreign policy through the lenses of realist, exceptionalist, or liberal institutionalist approaches. All the previously mentioned approaches tend to be based on etic studies conducted from the point of view of outsiders. The present interpretation of Japanese foreign policy applies an emic model based on primary sources from the Greater East Asian region and concludes that the Model of Harmony through Holistic Engagement shows considerable explanatory traction in interpreting the direction and development of Japanese foreign policy, in particular in the last two to three decades.

Probing the Movement of Helix F of $\alpha_1$-Antitrypsin

  • Baek, Je-Hyun;Kim, Jun;Yu, Myeong-Hee
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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    • pp.31-31
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    • 2002
  • $\alpha$$_1$-Antitrypsin is a member of the serine protease inhibitor (serpin) family that share a common tertiary structure. The reactive site loop (RSL) of serpins is exposed at one end of the molecule for protease binding. Upon cleavage by a target protease, the RSL is inserted into the major $\beta$-sheet A, which is a necessary process for formation of a tight inhibitory complex.(omitted)

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Coping with Violence in the Thai-Cambodian Border: The Silence of the Border

  • von Feigenblatt, Otto F.
    • Journal of Contemporary Eastern Asia
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    • 제10권2호
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    • pp.35-40
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    • 2011
  • The recent listing of Preah Vihear Temple as a World Heritage Site has awakened a longtime simmering border dispute between Thailand and Cambodia over a few square kilometers surrounding the ancient Khmer Temple. While the listing of the site by UNESCO was expected to revive the economy of the impoverished border towns near the temple due to the increased tourism and funding for the preservation of the archeological site, it has had the opposite effect due to the sharp increase in violent conflict carried out by the armed forces and nationalist activists from both sides. Military skirmishes and violent protests have brought the local economy to a halt in addition to causing considerable physical damage to the local infrastructure and to the local transnational network of ethnic Kui, local business owners, Khmer and Thai villagers. This paper shows how the dispute is viewed and undertaken by three distinct communities involved in the conflict, the militaries, the metropolitan political elites and activists, and the local villagers. The three communities represent three different cultures of conflict with different interests and most importantly with differential access to the media and official representations of the dispute.

LOXODROMES AND TRANSFORMATIONS IN PSEUDO-HERMITIAN GEOMETRY

  • Lee, Ji-Eun
    • 대한수학회논문집
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    • 제36권4호
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    • pp.817-827
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    • 2021
  • In this paper, we prove that a diffeomorphism f on a normal almost contact 3-manifold M is a CRL-transformation if and only if M is an α-Sasakian manifold. Moreover, we show that a CR-loxodrome in an α-Sasakian 3-manifold is a pseudo-Hermitian magnetic curve with a strength $q={\tilde{r}}{\eta}({\gamma}^{\prime})=(r+{\alpha}-t){\eta}({\gamma}^{\prime})$ for constant 𝜂(𝛄'). A non-geodesic CR-loxodrome is a non-Legendre slant helix. Next, we prove that let M be an α-Sasakian 3-manifold such that (∇YS)X = 0 for vector fields Y to be orthogonal to ξ, then the Ricci tensor 𝜌 satisfies 𝜌 = 2α2g. Moreover, using the CRL-transformation $\tilde{\nabla}^t$ we fine the pseudo-Hermitian curvature $\tilde{R}$, the pseudo-Ricci tensor $\tilde{\rho}$ and the torsion tensor field $\tilde{T}^t(\tilde{S}X,Y)$.

Numerical framework for stress cycle assessment of cables under vortex shedding excitations

  • Ruiz, Rafael O.;Loyola, Luis;Beltran, Juan F.
    • Wind and Structures
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    • 제28권4호
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    • pp.225-238
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    • 2019
  • In this paper a novel and efficient computational framework to estimate the stress range versus number of cycles curves experienced by a cable due to external excitations (e.g., seismic excitations, traffic and wind-induced vibrations, among others) is proposed. This study is limited to the wind-cable interaction governed by the Vortex Shedding mechanism which mainly rules cables vibrations at low amplitudes that may lead to their failure due to bending fatigue damage. The algorithm relies on a stochastic approach to account for the uncertainties in the cable properties, initial conditions, damping, and wind excitation which are the variables that govern the wind-induced vibration phenomena in cables. These uncertainties are propagated adopting Monte Carlo simulations and the concept of importance sampling, which is used to reduce significantly the computational costs when new scenarios with different probabilistic models for the uncertainties are evaluated. A high fidelity cable model is also proposed, capturing the effect of its internal wires distribution and helix angles on the cables stress. Simulation results on a 15 mm diameter high-strength steel strand reveal that not accounting for the initial conditions uncertainties or using a coarse wind speed discretization lead to an underestimation of the stress range experienced by the cable. In addition, parametric studies illustrate the computational efficiency of the algorithm at estimating new scenarios with new probabilistic models, running 3000 times faster than the base case.

The Merits of Social Credit Rating in China? An Exercise in Interpretive Pros Hen Ethical Pluralism

  • Clancy, Rockwell F.
    • Journal of Contemporary Eastern Asia
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    • 제20권1호
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    • pp.102-119
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    • 2021
  • Social credit rating in China (SCRC) has been criticized as "dystopian" and "Orwellian," an attempt by the Communist Party to hold onto power by exerting ever greater control over its citizens. To explain such measures, value differences are often invoked, that Chinese value stability and cooperation over privacy and freedom. However, these explanations are oversimplifications that result in ethical impasses. This article argues social credit rating should be understood in terms of the commonly human problem of large-scale cooperation. To do so, this paper relies on a cultural evolutionary framework and is an exercise in interpretive pros hen ethical pluralism, attempting to understand how apparently irresolvable cultural differences stem from common human concerns. Wholesale condemnation of SCRC fails to acknowledge the serious, intractable nature of problems resulting from a lack of trust in China. They take for granted the existence of institutions ensuring largescale, anonymous cooperation characteristic of - but somewhat unique to - Western Educated Industrialized Rich and Democratic (WEIRD) cultures. Because of its history and rapid development, China lacks the institutions necessary to ensure such cooperation, and because of anti-social punishment, social credit rating might be one of the few ways to ensure cooperation at this scale. The point is not to defend social credit rating in general, but to raise the possibility of its defense in China and show one way this would be done.

이동 통신 단말기용 초소형 3차원 안테나 제작 (Fabrication of a Subminiature 3 Dimensional Antenna for the Mobile Phone Handset)

  • 홍민기;손태호
    • 한국전자파학회논문지
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    • 제19권12호
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    • pp.1455-1461
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    • 2008
  • 휴대폰 내 수납 공간 체적이 1 cc 정도 되는 초소형 안테나를 제작하였다. 기본적인 형태는 IFA(Inverted F Antenna)이며, 전류 상쇄가 적도록 설계함으로써 안테나 효율을 높여 작은 체적에도 불구하고 높은 이득을 갖도록 하였다. 멀티 밴드의 구현에서 낮은 주파수 대역의 짧은 길이에 대한 보상은 헤릭스를 적용하였으며, 높은 주파수 대역을 위하여 3차원 구조의 패턴을 만들어 넣었다. 제작은 보드를 세트로 한 GSM/DCS 대역용 1 cc 안테나와 GSM/USPCS 대역 휴대폰 세트용 1.5 cc 안테나를 제작하고 제반 특성을 측정하였다. 각 안테나에 대한 측정 결과, 각 대역에서 평균 이득이 각각 $-3.46{\sim}-0.45\;dBi$$-4.80{\sim}-3.29\;dBi$로 매우 양호한 특성을 얻었다.

다양한 관엽식물의 근권부 박테리아 집단이 실내 휘발성 유기화합물질의 제거에 미치는 영향 (Effect of Bacterial Population from Rhizosphere of Various Foliage Plants on Removal of Indoor Volatile Organic Compounds)

  • 천세철;류명화;문영숙;신미호;손기철;정일민
    • 원예과학기술지
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    • 제28권3호
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    • pp.476-483
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    • 2010
  • 실내식물 9종의 근권부 하이드볼 배지에서 배양된 세균집단이 공기중 벤젠과 같은 휘발성 유기화합물의 제거효과에 미치는 영향이 조사되었다. 여러 식물 근권부의 배양토에서 배양된 세균 집단은 벤젠을 제거할 수 있었는데, $Spathiphyllum$ $wallisii$ Regel, $Pachira$ $aquatica$, $Ficus$ $elastica$, $Dieffenbachia$ sp. 'Marrianne' Hort., $Chamaedorea$ $elegans$ 식물들은 벤젠의 초기농도를 1.000으로 기준하였을 때, 세균 집단이 전혀 없는 배지의 대조구 초기 농도 대비 잔류율이 0.596이었으나 상기 언급한 식물들은 0.741-1.000으로서 벤젠의 농도를 현저히 감소시켰다(LSD, $P$=0.05). 이와 같은 경향은 식물의 종류에 따라 차이는 있었지만 톨루엔의 경우에도 비슷하게 나타났다. 이러한 결과를 바탕으로 $P.$ $aquatic$ 근권부의 배양토로부터 배양된 세균 집단을 $P.$ $aquatica$, $F.$ $elastica$, $S.$ $podophyllum$에 접종하였을 때 접종하지 않은 식물들에 비하여 벤젠과 톨루엔을 현저히 제거하는 효과가 나타나, 근권부의 미생물 집단을 이용하여 공기 중 휘발성 유기화합물(VOC)을 제거할 수 있음을 보여 주었다.