• Title/Summary/Keyword: Twisted

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Design of the Artificial Antenna System in Photosynthesis

  • Tamiaki, Hitoshi;Yagai, Shiki
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.66-69
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    • 2002
  • Zinc chlorin 1 possessing tertiary 3$^1$_hydroxy and 13$^1$-oxo groups was synthesized as a model for the antenna chlorophylls of photosynthetic green bacteria. Self-aggregation of 1 in nonpolar organic solvents was examined and compared to 2 and 3 possessing a secondary and primary 3$^1$_hydroxy group, respectively. Zinc chlorin 1 self-aggregated in I%(v/v) CH$_2$Cl$_2$-hexane to form oligomers and showed a red-shifted Qy maximum at 704 nm compared to the monomer (648 nm in CH$_2$CI2$_2$). This red-shift is larger than that of 3$^1$S-2 (648 to 697 nm) and comparable to that of3$^1$R-2 (648 to 705 nm), but smaller than that of 1 (648 to 740 nm), indicating that while a single 3$^1$-methyl group (primary to secondary OH) suppressed tight and/or extended aggregation, the additional 3$^1$-methyl group (secondary to tertiary OH) did not further suppress aggregation. The relative stability of the aggregates was in the order 3> 3$^1$R-2∼ 1 > 3$^1$S-2 as determined by visible spectral analyses. Molecular modeling calculations on oligomers of zinc chlorins 1, 3$^1$ R-2 and 3 gave similar well-ordered energy-minimized structures, while 3 stacked more tightly than 3$^1$ R- 2 and 1. In contrast, 3$^1$S-2 gave a relatively disordered (twisted) structure. The calculated oligomeric structures could explain the visible spectral data of 1-3 in nonpolar organic solvents. Moreover, self- aggregation of synthetic zinc 13$^1$_oxo-hlorins 4-6 possessing a 2-hydroxyethyl, 3-hydroxypropyl and 3- hydroxy-I-propenyl group at the 3-position in nonpolar organic solvents was discussed.

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Analysis of Cis- Trans Photoisomerization Mechanism of Rhodopsin Based on the Tertiary Structure of Rhodopsin

  • Yamada, Atsushi;Yamato, Takahisa;Kakitani, Toshiaki;Yamamoto, Shigeyoshi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.51-54
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    • 2002
  • We propose a novel mechanism (Twist Sharing Mechanism) for the cis-trans photoisomerization of rhodopsin, based on the molecular dynamics (MD) simulation study. New things devised in our simulations are (1) the adoption of Mt. Fuji potentials in the excited state for twisting of the three bonds C9=C10, C11=C12 and C13=14 which are modeled using the detailed ab initio quantum chemical calculations and (2) to use the rhodopsin structure which was resolved recently by the X-ray crystallographic study. As a result, we found the followings: Due to the intramolecular steric hindrance between 20-methyl and 10-H in the retinal chromophore, the C12-C13 and C10-C11 bonds are considerably twisted counterclockwise in rhodopsin, allowing only counterclockwise rotation of the C11 =C12 in the excited state. The movement of 19-methyl in rhodopsin is blocked by the surrounding three amino acids, Thr 118, Met 207 and Tyr 268, prohibiting the rotation of C9=C10. As a result only all-trans form of the chromophore is obtainable as a photoproduct. At the 90$^{\circ}$ twisting of C11=C12 in the course of photoisomerization, twisting energies of the other bonds amount to about 20 kcal/mol. If the transition state for the thermal isomerization is assumed to be similar to this structure, the activation energy for the thermal isomerization around C11=C12'in rhodopsin is elevated by about 20 kcal/mol and the thermal isomerization rate is decelerated by 10$\^$-14/ times than that of the retinal chromophore in solution, protecting photosignal from the thermal noise.

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The Characteristics of Textiles excavated in Soochonri Tombs of $5^{th}$ Century Baekjae Period (백제 5세기 수촌리 고분군 직물의 특성)

  • Park, Yoon-Mee;Jeong, Bok-Nam
    • Journal of the Korean Society of Costume
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    • v.58 no.10
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    • pp.164-172
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    • 2008
  • Soochonri tombs are assumed to be of the Baekje Kingdom in the early 5th century. We have examined 12 artifacts and 24 textiles in the four tombs. Along with hemp textiles, silk and embroidery threads were found In the Soochonri tombs. Within the hemp textiles both hemp and ramie were made using s-twist threads and the thread count distribution is calculated to be $8.5{\sim}15.5/cm^2$. Taffeta, one of the silk, can be categorized in to four types. First, the plain woven silk was made with warp and weft of the same thickness. The rates of thread count are also similar. Secondly the warp and weft are of the same thickness but has more spaces between threads. Third, the type of warp and weft is different in thickness, the thicker thread woven in the same direction. Lastly, a textile was woven with spaces the same as the width of the reed mark in every two warps. There were five compound weave found. Among them one was made with non-twisted thread for warp and s-twist thread for weft. One plain braiding with apparent spaces between threads were found. All three of the twining were made with wefts thicker than warps, barely showing the warps as a result. Textiles of the Soochonri tombs are the oldest of the Baekje Kingdom studied by far and therefore important artifacts of the Baekje Kingdom. These textiles are similar to those found in the King Muryeong's Tomb and tombs of Gaya and Shilla.

Aerodynamic and Aeroelastic Tool for Wind Turbine Applications

  • Viti, Valerio;Coppotelli, Giuliano;De Pompeis, Federico;Marzocca, Pier
    • International Journal of Aeronautical and Space Sciences
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    • v.14 no.1
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    • pp.30-45
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    • 2013
  • The present work focuses on the unsteady aerodynamics and aeroelastic properties of a small-medium sized wind-turbine blade operating under ideal conditions. A tapered/twisted blade representative of commercial blades used in an experiment setup at the National Renewable Energy Laboratory is considered. The aerodynamic loads are computed using Computational Fluid Dynamics (CFD) techniques. For this purpose, FLUENT$^{(R)}$, a commercial finite-volume code that solves the Navier-Stokes and the Reynolds-Averaged Navier-Stokes (RANS) equations, is used. Turbulence effects in the 2D simulations are modeled using the Wilcox k-w model for validation of the CFD approach. For the 3D aerodynamic simulations, in a first approximation, and considering that the intent is to present a methodology and workflow philosophy more than highly accurate turbulent simulations, the unsteady laminar Navier-Stokes equations were used to determine the unsteady loads acting on the blades. Five different blade pitch angles were considered and their aerodynamic performance compared. The structural dynamics of the flexible wind-turbine blade undergoing significant elastic displacements has been described by a nonlinear flap-lag-torsion slender-beam differential model. The aerodynamic quasi-steady forcing terms needed for the aeroelastic governing equations have been predicted through a strip-theory based on a simple 2D model, and the pertinent aerodynamic coefficients and the distribution over the blade span of the induced velocity derived using CFD. The resulting unsteady hub loads are achieved by a first space integration of the aeroelastic equations by applying the Galerkin's approach and by a time integration using a harmonic balance scheme. Comparison among two- and three- dimensional computations for the unsteady aerodynamic load, the flap, lag and torsional deflections, forces and moments are presented in the paper. Results, discussions and pertinent conclusions are outlined.

Efficient simulation method for a gas inflow to the central molecular zone

  • Shin, Jihye;Kim, Sungsoo S.;Baba, Junichi;Saitoh, Takayuki R.;Chun, Kyungwon;Hozumi, Shunsuke
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.59.1-59.1
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    • 2015
  • We present hydrodynamic simulations of gas clouds that inflowing from the disk to a few hundred parsec region of the Milky Way. Realistic Galactic structures are included in our simulations by thousands of multipole expansions that describe 6.4 million stellar particles of a self-consistent Galaxy simulation (Baba, Saitoh & Wada, in prep.). We find that a hybrid multipole expansion model with two different basis sets and a thick disk correction well reproduces the overall structures of the Milky Way. We find that the nuclear ring evolves into 240 pc at T~1500 Myr, regardless of the initial size. For most of simulation runs, gas inflow rate to the nuclear region is equilibrated as ~0.02 Msun/yr, and thus accumulated gas mass and star formation activity is stabilized as $6{\times}10^7Msun$ and ~0.02M/yr, respectively. These stabilized values are in a good agreement with estimations for the CMZ. The nuclear ring is off-centered to the Galactic center by the lopsided central mass distribution of the Galaxy model, and thus an asymmetric mass distribution is arose accordingly. The lopsidedness also leads the nuclear ring to be tilted to the Galactic plane and to precess along the Galaxy rotation. In early evolutionary stage when gas clouds start to inflow and form the nuclear ring, the z-directional oscillations of the gas clouds results in the twisted, infinity-shaped nuclear ring. Since the infinity-shaped feature is transient only for first 100 Myr, the current infinity-shape observed in the CMZ may indicate that the CMZ forms quite recently.

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Antagonistic Bacillus species as a biological control of ginseng root rot caused by Fusarium cf. incarnatum

  • Song, Minjae;Yun, Hye Young;Kim, Young Ho
    • Journal of Ginseng Research
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    • v.38 no.2
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    • pp.136-145
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    • 2014
  • Background: This study aimed to develop a biocontrol system for ginseng root rot caused by Fusarium cf. incarnatum. Methods: In total, 392 bacteria isolated from ginseng roots and various soils were screened for their antifungal activity against the fungal pathogen, and a bacterial isolate (B2-5) was selected as a promising candidate for the biocontrol because of the strong antagonistic activity of the bacterial cell suspension and culture filtrate against pathogen. Results: The bacterial isolate B2-5 displayed an enhanced inhibitory activity against the pathogen mycelial growth with a temperature increase to $25^{\circ}C$, produced no pectinase (related to root rotting) an no critical rot symptoms at low [$10^6$ colony-forming units (CFU)/mL] and high ($10^8CFU/mL$) inoculum concentrations. In pot experiments, pretreatment with the bacterial isolate in the presumed optimal time for disease control reduced disease severity significantly with a higher control efficacy at an inoculum concentration of $10^6CFU/mL$ than at $10^8CFU/mL$. The establishment and colonization ability of the bacterial isolates on the ginseng rhizosphere appeared to be higher when both the bacterial isolate and the pathogen were coinoculated than when the bacterial isolate was inoculated alone, suggesting its target-oriented biocontrol activity against the pathogen. Scanning electron microscopy showed that the pathogen hyphae were twisted and shriveled by the bacterial treatment, which may be a symptom of direct damage by antifungal substances. Conclusion: All of these results suggest that the bacterial isolate has good potential as a microbial agent for the biocontrol of the ginseng root rot caused by F. cf. incarnatum.

No-bias-bend pi cell using the rubbed polyimide mixture

  • Kim, Dae-Hyeon;Park, Hong-Gyu;Kim, Yeong-Hwan;Kim, Byeong-Yong;Ok, Cheol-Ho;Han, Jeong-Min;Seo, Dae-Sik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.186-186
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    • 2009
  • Most liquid crystal display modes, including the twisted nematic (TN) $mode^1$, the in-plane switching (IPS) $mode^2$, the fringe field switching (FFS) $mode^3$, and the vertically aligned (VA) $mode^4$ are based on either a horizontal or a vertical alignment. However, for some applications, such as no-bias-bend (NBB) pi cell or bistable bend-splay display, an intermediate pretilt angle is essential$^5$. NBB pi cells have been a focus of interest because of their fast response time; however, the reliable control of the intermediate pretilt angle of liquid crystals that is required for the fabrication of NBB pi cells is challenging. The controllable pre-tilt angle of liquid crystals was investigated using a blend of horizontal and vertical polyimide prepared by a rubbing method. Various pretilt angles in the range from 0^{\circ}$ to 90^{\circ}$ were achieved as a function of the vertical polyimide content. We observed uniform liquid crystal alignment on the rubbing-treated blended polyimide layer. A NBB pi cell with an intermediate pretilt angle of 47.8^{\circ}$ was manufactured. This cell had no initial bias voltage and a low threshold voltage, which indicates that it has low power consumption. In addition, the response time of the NBB pi cell was rapid.

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Analysis of the Constructional Components of Chanel Jacket Design (샤넬 재킷 디자인의 구성학적 요소 분석)

  • Choi, Se-Lin;Do, Wol-Hee;Lee, Mi-Suk
    • Fashion & Textile Research Journal
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    • v.20 no.3
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    • pp.266-278
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    • 2018
  • This study investigated the transformation of the Chanel jacket by looking at clothing design and constructional components. This study explored Chanel jacket's designs from 2001 S/S to 2016-17 F/W, and collected designs from Samsung Design Net and Vogue. The study used 690 designs with the following results. First, in the silhouette of the Chanel jacket, straight silhouette and hourglass silhouette had the most; in addition, in the length, hip line and under hip line were in order. Second, in case of collar and neckline, the form of a non-collar was the most and revealed the persistence of round neckline which is the basic style of a Chanel jacket. Third, in the shape of sleeves, the loose-fit straight sleeves, wide sleeves, and cocoon sleeves appeared most often. In method of closure, button, zipper were in order, and snaps or without closure appeared. Fourth, in the form of braids, various forms such as twisted yarns, leashes, or lace were used, and patch pockets were mainly used in pockets. Chanel maintains its original design by using various methods. Chanel tried to improve activity and functionality through silhouettes, lengths, necklines, and sleeves. The unchanging expression of the world of Chanel will continue to display and inherit future value. This study can provide Chanel's unique characteristics and new ideas that can transform their origins for jacket design.

Incidence of apical crack formation and propagation during removal of root canal filling materials with different engine driven nickel-titanium instruments

  • Ozyurek, Taha;Tek, Vildan;Yilmaz, Koray;Uslu, Gulsah
    • Restorative Dentistry and Endodontics
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    • v.42 no.4
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    • pp.332-341
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    • 2017
  • Objectives: To determine the incidence of crack formation and propagation in apical root dentin after retreatment procedures performed using ProTaper Universal Retreatment (PTR), Mtwo-R, ProTaper Next (PTN), and Twisted File Adaptive (TFA) systems. Materials and Methods: The study consisted of 120 extracted mandibular premolars. One millimeter from the apex of each tooth was ground perpendicular to the long axis of the tooth, and the apical surface was polished. Twenty teeth served as the negative control group. One hundred teeth were prepared, obturated, and then divided into 5 retreatment groups. The retreatment procedures were performed using the following files: PTR, Mtwo-R, PTN, TFA, and hand files. After filling material removal, apical enlargement was done using apical size 0.50 mm ProTaper Universal (PTU), Mtwo, PTN, TFA, and hand files. Digital images of the apical root surfaces were recorded before preparation, after preparation, after obturation, after filling removal, and after apical enlargement using a stereomicroscope. The images were then inspected for the presence of new apical cracks and crack propagation. Data were analyzed with ${\chi}^2$ tests using SPSS 21.0 software. Results: New cracks and crack propagation occurred in all the experimental groups during the retreatment process. Nickel-titanium rotary file systems caused significantly more apical crack formation and propagation than the hand files. The PTU system caused significantly more apical cracks than the other groups after the apical enlargement stage. Conclusions: This study showed that retreatment procedures and apical enlargement after the use of retreatment files can cause crack formation and propagation in apical dentin.

"Elsa, Why are you in Fear and Anger?": The Power of Magic and Control of Emotion in Frozen ("엘사여, 뭐가 그리 두렵고 분한가?": 『겨울왕국』에서의 마술의 힘과 감정의 통제)

  • Park, Eun Jung
    • Journal of Digital Contents Society
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    • v.17 no.6
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    • pp.613-621
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    • 2016
  • This paper has the first aim to analyze Elsa's magic power of why and how she, as a heroine in the animation of Frozen, is in the emotion of fear and anger. This paper will explain why these two emotions are twisted compound to identify Elsa's iced emotion in the ice kingdom. And secondly, this paper attempts to connect Elsa's fear emotion in her real life is the other flip with that of anger throughout the characters' network in Frozen, which symbolically reflect the feminine pattern of real society that Walt Disney prospects for the dream society. Through the cognitive process for Elsa's ice kingdom between emotion status and social network, we can assume the pattern of social network with emotional chart and the archetype of human emotion through the cognitive-emotional storytelling on the emotion of Elsa in Frozen.