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Inhibitory Mechanism of Novel Inhibitors of UDP-N-Acetylglucosamine Enolpyruvyl Transferase from Haemophilus influenzae

  • Jin, Bong-Suk;Han, Seong-Gu;Lee, Won-Kyu;Ryoo, Sung-Weon;Lee, Sang-Jae;Suh, Se-Won;Yu, Yeon-Gyu
    • Journal of Microbiology and Biotechnology
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    • v.19 no.12
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    • pp.1582-1589
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    • 2009
  • Bacterial UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) catalyzes the transfer of enolpyruvate from phosphoenolpyruvate (PEP) to uridine diphospho-N-acetylglucosamine (UNAG), which is the first step of bacterial cell wall synthesis. We identified thimerosal, thiram, and ebselen as effective inhibitors of Haemophilus influenzae MurA by screening a chemical library that consisted of a wide range of bioactive compounds. When MurA was preincubated with these inhibitors, their 50% inhibitory concentrations ($IC_{50}s$) were found to range from 0.1 to $0.7\;{\mu}M$. In particular, thimerosal suppressed the growth of several different Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhimurium at a concentration range of $1-2\;{\mu}g/ml$. These inhibitors covalently modified the cysteine residue near the active site of MurA. This modification changed the open conformation of MurA to a more closed configuration, which may have prevented the necessary conformational change from occurring during the enzyme reaction.

The Fabrication of PVA Polymer Coated on the Surface of B4C Nanocomposite by High Energy Ball Mill (고에너지볼밀을 이용한 PVA 고분자가 표면 코팅된 B4C 나노복합재 제조)

  • Uhm, Young-Rang;Kim, Jae-Woo;Jung, Jin-Woo;Rhee, Chang-Kyu
    • Journal of Powder Materials
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    • v.16 no.2
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    • pp.110-114
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    • 2009
  • Mechanical coating process was applied to form 89 %-hydrolyzed poly vinyl alcohol (PVA) onto boron carbide ($B_4C$) nanopowder using one step high energy ball mill method. The polymer layer coated on the surface of B4C was changed to glass-like phase. The average particle size of core/shell structured $B_4C$/PVA was about 50 nm. The core/shell structured $B_4C$/PVA was formed by dry milling. However, the hydrolyzed PVA of $98{\sim}99%$ with high glass transition temperature ($T_g$) was rarely coated on the powder. The $T_g$ of polymer materials was one of keys for guest polymer coating on to the host powder by solvent free milling.

Moving area detection for moving object tracking (이동 객체 추적을 위한 움직임 영역 검출)

  • 오명관;최동진;전병민
    • Proceedings of the Korea Contents Association Conference
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    • 2003.11a
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    • pp.281-284
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    • 2003
  • In this study, we have proposed the method of moving area detection as the preprocessing step of moving object tracking system. First, we catch the two frames which are different at time in image sequence. We obtain the moving area by using their binary differential image. In differential image, the object area of previous and current frame is present. In the tracking system, the background is changed by camera motion. So, in this case we have to decide which moving area of object is current at time. We obtain the binary edge image of current frame by applying a threshold to the output of an edge detector. Then we performed logical AND operation between the edge image and differential image. As a result of this work moving area of object can be detected.

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Partial sectional confinement in a quasi-encased steel-concrete composite beam

  • Hassanzadeh, Amir Masoud;Dehestani, Mehdi
    • Computers and Concrete
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    • v.22 no.3
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    • pp.269-278
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    • 2018
  • In the recent decades, the application of composite materials, due to their desirable properties, has increased dramatically. In the present study, a quasi-encased trapezoidal section composite steel beam encased with concrete is thoroughly examined. Calculation of the load bearing capacity is carried out by finite element modeling of concrete and FRP beams with trapezoidal section under the effect of controlled displacement loading. The results are then validated comparing to the existing experimental results obtained from similar studies. Further on, the materials are changed to steel and concrete, and the section is de-signed in such a way that both concrete and steel reach a high percent-age of their load bearing capacity. In the last step, the parameters affecting the bending capacity and the behavior of the semi-confined composite beam are investigated. Results revealed that the beam diagonal web thickness plays the most effective role in load bearing capacity amongst other studied parameters. Furthermore, by analyzing the results on the effect of different parameters, an optimal model for primary beam section is presented, which exhibits a greater load bearing capacity compared to the initial design with the same amount of materials used for both sections.

Analysis of Heme Biosynthetic Pathways in a Recombinant Escherichia coli

  • Pranawidjaja, Stephanie;Choi, Su-In;Lay, Bibiana W.;Kim, Pil
    • Journal of Microbiology and Biotechnology
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    • v.25 no.6
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    • pp.880-886
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    • 2015
  • Bacterial heme was produced from a genetic-engineered Escherichia coli via the porphyrin pathway and it was useful as an iron resource for animal feed. The amount of the E. coli-synthesized heme, however, was only few milligrams in a culture broth and it was not enough for industrial applications. To analyze heme biosynthetic pathways, an engineered E. coli artificially overexpressing ALA synthase (hemA from Rhodobacter sphaeroides) and pantothenate kinase (coaA gene from self geneome) was constructed as a bacterial heme-producing strain, and both the transcription levels of pathway genes and the intermediates concentrations were determined from batch and continuous cultures. Transcription levels of the pathway genes were not significantly changed among the tested conditions. Intracellular intermediate concentrations indicated that aminolevulinic acid (ALA) and coenzyme A (CoA) were enhanced by the hemA-coaA co-expression. Intracellular coproporphyrinogen I and protoporphyrin IX accumulation suggested that the bottleneck steps in the heme biosynthetic pathway could be the spontaneous conversion of HMB to coproporphyrinogen I and the limited conversion of protoporphyrin IX to heme, respectively. A strategy to increase the conversion of ALA to heme is discussed based on the results.

In-Car Video Stabilization using Focus of Expansion

  • Kim, Jin-Hyun;Baek, Yeul-Min;Yun, Jea-Ho;Kim, Whoi-Yul
    • Journal of Korea Multimedia Society
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    • v.14 no.12
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    • pp.1536-1543
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    • 2011
  • Video stabilization is a very important step for vision based applications in the vehicular technology because the accuracy of these applications such as obstacle distance estimation, lane detection and tracking can be affected by bumpy roads and oscillation of vehicle. Conventional methods suffer from either the zooming effect which caused by a camera movement or some motion of surrounding vehicles. In order to overcome this problem, we propose a novel video stabilization method using FOE(Focus of Expansion). When a vehicle moves, optical flow diffuses from the FOE and the FOE is equal to an epipole. If a vehicle moves with vibration, the position of the epipole in the two consecutive frames is changed by oscillation of the vehicle. Therefore, we carry out video stabilization using motion vector estimated from the amount of change of the epipoles. Experiment results show that the proposed method is more efficient than conventional methods.

Cases Studies and Activation Method of Exhibition Working-Activity Satellite (지역 체험형박물관의 사례조사 및 활성화방안 연구)

  • Jung, Jinju;Choi, Hyoseung
    • Journal of the Korean Institute of Rural Architecture
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    • v.7 no.2
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    • pp.21-30
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    • 2005
  • It is not entirely new tendency now that museum have to become 'participation and working activity style' in 21st century. A lot of museums are changed fast to that visitors participate and work actively in museum program recently in Korea. Cheongju city is building various museums which have interesting themes contributed precious inheritances and collections belong to citizens. And Cheongju city is pushing ahead long-term target which is Ecomuseum City Cheongju with citizen is progressing for cultural city continuously. Also to become public museums and facilities which visitors want to come again, Cheongju city is trying to secure various experience space and facilities to keep in step in trend that visitors take part in and work actively in museum program. In an area, there are various cultural, historical, natural and industrial heritages that express relation of human and environment. In meaning that do function of antenna of sending culture which understanding, studying, informing these regional inheritances and promoting activity, in Ecomuseum, those are called "satellite" included not only regional preserved inheritances but also various theme museums which have mutual cooperative function. Satellite(or antenna) is very important element composing Ecomuseum. So I want to provide that is "Exhibition Working-Activity Satellite" that are places having experience space or facilities which visitors can work actively there like that. Such study for Ecomuseum and Exhibition Working-Activity Satellite can be promoted Ecomuseum City which is city for learning lifetime with citizens.

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Investigation of Physicochemical Properties of Mo Carbide Utilizing Electron Spectroscopy

  • Jeong, Eunkang;Park, Juyun;Kang, Yong-Cheol
    • Journal of Integrative Natural Science
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    • v.13 no.3
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    • pp.87-91
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    • 2020
  • Molybdenum carbide (MoCx) thin films (TFs) were deposited by reactive radio frequency (rf) magnetron co-sputtering in high vacuum chamber. We compared the properties of MoCx thin films as the rf power changed on C target. The result of alpha step measurement showed that the thickness of the MoCx TFs varied from163.3 to 194.86 nm as C power was increased from 160 to 200 W. The crystallinity of MoCx such as b-Mo2C, Mo2C, and diamond like carbon (DLC) structures were observed by XRD. The oxidation states of Mo and C were determined using high resolution XPS spectra of Mo 3d and C 1s were deconvoluted. Molybdenum was consisted of Mo, Mo4+, and Mo6+ species. And C was deconvoluted to C-Mo, C, C-O, and C=O species.

Biphasic Tumor Oxygenation during Respiratory Challenge may Predict Tumor Response during Chemotherapy

  • Lee, Songhyun;Jeong, Hyeryun;Anguluan, Eloise;Kim, Jae Gwan
    • Current Optics and Photonics
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    • v.2 no.1
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    • pp.1-6
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    • 2018
  • Our previous study showed that switching the inhaled gas from hypoxic gas to hyperoxic gas for 10 minutes increased tumor oxygenation and that the magnitude of oxyhemoglobin increase responded earlier than tumor volume change after chemotherapy. During 10 minutes of inhaled-oxygen modulation, oxyhemoglobin concentration first shows a rapid increase and then a slow but gradual increase, which has been fitted with a double-exponential equation in this study. Two amplitude values, amplitudes 1 and 2, respectively represent the magnitudes of rapid and slow increase of oxyhemoglobin. The trends of changes in amplitudes 1 and 2 were different, depending on tumor volume when chemotherapy started. However, both amplitudes 1 and 2 changed earlier than tumor volume, regardless of when chemotherapy was initiated. These results imply that by observing amplitude 1 changes post chemotherapy, we can reduce the time of a respiratory challenge from 10 minutes to less than 2 minutes, to see the chemotherapy response. We believe that by reducing the time of the respiratory challenge, we have taken a step forward to translating our previous study into clinical application.

The Effects of Insoles for Postural Correction on Spatial-temporal Changes of Gait in Spastic Cerebral Palsy Children

  • Kim, Hee Tak;Lim, Sang Wan
    • Journal of International Academy of Physical Therapy Research
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    • v.6 no.2
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    • pp.840-845
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    • 2015
  • Improvement in functional gait is one of treatment goals in treatment of cerebral palsy children. This study intended to examine the effects of insoles for postural correction on gait in spastic cerebral palsy patients by investigating changes in gait temporal spatial parameters. As the subjects, 15 spastic bilateral cerebral palsy patients participated in this study. Temporal spatial parameters of gait were measured using GAITRite system under three gait conditions. Bare foot gait, gait in shoes, and gait in insoles for postural correction were conducted. In order to look at differences in temporal spatial parameters according to three gait conditions, repeated one way analysis of variance was conducted. As post hoc test, Bonferroni was conducted. A significant level was set at ${\alpha}=.05$. According to the result of this study, gait velocity, cadence, step length, stride length of the left lower extremity significantly changed. When the subjects put on customized insoles for postural correction, the effect was greatest. There were no significant changes in stance time, single support time, double support time, swing % of gait, and stance % of cycle. Therefore, gait with insoles for postural correction positively influenced functional gait improvement and will be able to be usefully employed for spastic cerebral palsy children as one of gait assistance devices.