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Development of a Rapid and Productive Cell-free Protein Synthesis System

  • Kim, Dong-Myung;Choi, Cha-Yong;Ahn, Jin-Ho;Kim, Tae-Wan;Kim, Nam-Young;Oh, In-Suk;Park, Chang-Gil
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.3
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    • pp.235-239
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    • 2006
  • Due to recent advances in genome sequencing, there has been a dramatic increase in the quantity of genetic information, which has lead to an even greater demand for a faster, more parallel expression system. Therefore, interest in cell-free protein synthesis, as an alternative method for high-throughput gene expression, has been revived. In contrast to in vivo gene expression methods, cell-free protein synthesis provides a completely open system for direct access to the reaction conditions. We have developed an efficient cell-free protein synthesis system by optimizing the energy source and S30 extract. Under the optimized conditions, approximately $650{\mu}g/mL$ of protein was produced after 2h of incubation, with the developed system further modified for the efficient expression of PCR-amplified DNA. When the concentrations of DNA, magnesium, and amino acids were optimized for the production of PCR-based cell-free protein synthesis, the protein yield was comparable to that from the plasmid template.

Proper Mixing Ratio for Securing Quality of Free-form Panel (비정형 패널의 형상 품질확보를 위한 적정 배합비 도출)

  • Kim, Min-Sik;Park, Chae-Wool;Kim, Ki-Hyuk;Do, Sung-Lok;Lee, Dong-Hoon
    • Journal of the Korea Institute of Building Construction
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    • v.19 no.5
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    • pp.449-456
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    • 2019
  • Recent developments in architectural technologies and programs have enabled architects to think creatively and design free-form architecture. however, there are many problems in the production technology of FCP(Free-Form Concrete Panel). In particular, reduced accuracy due to lack of free-form panel production technology can lead to redesign of buildings as a result, problems such as an increase in construction cost and period. Therefore, this experiment aimed to compensate the decrease of the accuracy according to the displacement difference and to derive the proper mixing ratio for maintaining the shape during the free-form panel curing. In this study, molds were made using paraffin that is a recyclable phase change material. Concrete Panel is usually produced from Portland cement, dead burn magnesia, phosphate, borax and fine aggregate. In this study, four mixing ratios of FCP were selected after each material was blended to determine the proper blending ratio of the fluidity phase, the water absorption rate and the water content of the test piece. FCP was fabricated on the basis of the selected four compounding ratios and thickness and error rate were measured. Based on the error rate of the measured FCP, the quality standard was satisfied among the four compounding ratios.

The Great Saphenous Vein-An Underrated Recipient Vein in Free Flap Plasty for Lower Extremity Reconstruction: A Retrospective Monocenter Study

  • Meiwandi, Abdulwares;Kamper, Lars;Kuenzlen, Lara;Rieger, Ulrich M.;Bozkurt, Ahmet
    • Archives of Plastic Surgery
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    • v.49 no.5
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    • pp.683-688
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    • 2022
  • Background Reconstruction of large soft tissue defects of the lower extremity often requires the use of free flaps. The main limiting factor and potential for complications lie in the selection of proper donor and recipient vessels for microvascular anastomosis. While the superficial veins of the lower leg are easier to dissect, they are thought to be more vulnerable to trauma and lead to a higher complication rate when using them instead of the deep accompanying veins as recipient vessels. No clear evidence exists that proves this concept. Methods We retrospectively studied the outcomes of 97 patients who underwent free flap plasty to reconstruct predominantly traumatic defects of the lower extremity at our institute. The most used flap was the gracilis muscle flap. We divided the population into three groups based on the recipient veins that were used for microvascular anastomosis and compared their outcomes. The primary outcome was the major complication rate. Results Overall flap survivability was 93.81%. The complication rates were not higher when using the great saphenous vein as a recipient vessel when comparing to utilizing the deep concomitant veins alone or the great saphenous vein in combination to the concomitant veins. Conclusions In free flap surgery of the lower extremity, the selection of the recipient veins should not be restricted to the deep accompanying veins of the main vessels. The superficial veins, especially the great saphenous vein, offer an underrated option when performing free flap reconstruction.

Effect of the new needle-free injection system on pain perception and dental anxiety during anesthesia: randomized controlled split-mouth study

  • Melek Belevcikli;Halenur Altan;Osman Demir
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.23 no.1
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    • pp.1-8
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    • 2023
  • Backgrounds: Pain management is one of the most important factors affecting the success of pediatric dentistry. Therefore, new needle- and pain-free local anesthesia techniques have been developed in parallel with technological advancements. The purpose of this study is to compare the pain perception and dental anxiety levels associated with a needle-free injection system (Comfort-inTM) and the classic needle method during treatment-required infiltration anesthesia in children. Methods: This randomized controlled crossover split-mouth clinical study included 94 children who required dental treatment with local anesthesia using a dental needle or needle-free injection system for the bilateral primary molars. The Wong-Baker Scale (WBS) was used to measure pain perception at different times, and the Modified Child Dental Anxiety Scale (MCDAS) was used to measure the anxiety level of the child. A statistical software package was used to process the data. Statistical significance was set at P < 0.05. Results: There was no significant difference between the needle-free injection system and dental needle method during the induction stage for filling and pulpotomy (P > 0.05). "Pain on postoperative 1st day" was similar in both types of anesthesia (P = 0.750). Conclusions: The needle-free injection system was as effective as the dental needle method. The Comfort-inTM system was an acceptable alternative for patients during the postoperative period. Understanding how pain management may be provided during local anesthesia administration and a child's fear and anxiety regarding the dentist may lead to better dental compliance.

Computational Flow Analysis on Improvement Effect of Wind Shear by a Structure Installed Upstream of a Wind Turbine (풍력발전기 풍상부 지면설치 구조물에 의한 풍속전단 개선효과의 전산유동해석)

  • Kim, Hyun-Goo;Woo, Sang-Woo;Jang, Moon-Seok;Shin, Hyuong-Ki
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.278-281
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    • 2008
  • This study demonstrates the advantages of a shear-free structure designed to modify vertical profiles of wind speed in the atmospheric surface layer. Computational fluid dynamics(CFD) software, FLUENT is used to interpret the velocity field modification around the structure and wind turbine. The shapes of shear-free structure, installed at upstream toward prevailing wind direction, would be fences, buildings and trees, etc. According to the simulation results, it is obvious that wind shear between heights of wind turbine's blades is decreased together with a speed-up advantage. This would lead decrease of periodic wind loading caused by wind shear and power-out increase by flow uniformity and wind speed-up.

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A Multi-Axis Contour Error Controller for High-Speed/High-Precision Machining of Free form Curves (고속 고정밀의 자유곡선 가공을 위한 다축 윤곽오차 제어)

  • 이명훈;최정희;이영문;양승한
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.4
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    • pp.64-71
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    • 2004
  • The growing need for higher precision and productivity in manufacturing industry has lead to an increased interest in computer numerical control (CNC) systems. It is well known fact that the cross-coupling controller (CCC) is an effective method for contouring applications. In this paper, a multi-axis contour error controller (CEC) based on a contour error vector using parametric curve interpolator is introduced. The contour error vector is a vector from the actual tool position to the nearest point on the desired path. The contour error vector is the closest error model to the contour error. The simulation results show that the CEC is more accurate than the conventional CCC for a biaxial motion system. In addition, the experimental results on 3-axis motion system show that the CEC is simply applied to 3-axis motions and contouring accuracy is significantly improved.

Lift-Off Voltage and Partial Discharge Characteristics of Free Metallic Particles in GIS (GIS 내 금속입자의 부상전압과 부분방전특성 연구)

  • Yun, Jin-Yeol;Han, Sang-Ok
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.2
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    • pp.127-132
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    • 1999
  • Both motion of free metallic particles from which most GIS internal failures are caused and partial discharges from the particles were examined using EHV GIS test chamber. Effects from particle length and gas pressure which are main factors to lead to breakdown failure were investigated theoretically and experimentally. Magnitude of both lift-off voltage and partial discharge inception voltage were measured respectively and, through these measurements, this paper showed the possibility of predicting breakdown fault and of taking action to prevent the fault in advance. The measurement of partial discharge when the particles began to move could be adopted to decide minimum sensitivity in developing predictive diagnostic equipments. Both the amount of apparent discharge and real discharge in GIS were examined theoretically and experimentally, then experimental results were analyzed on the basis of the theory.

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Trasient Liquid Phase bonding for Power Semiconductor (전력반도체 패키징을 위한 Transient liquid phase 접합 기술)

  • Roh, Myong-Hoon;Nishikawa, Hiroshi;Jung, Jae Pil;Kim, Wonjoong
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.1
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    • pp.27-34
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    • 2017
  • Recently, a demand in sustainable green technologies is requiring the lead free bonding for high power module packaging due to the environmental pollution. The Transient-liquid phase (TLP) bonding can be a good alternative to a high Pb-bearing soldering. Basically, TLP bonding is known as the combination of soldering and diffusion bonding. Since the low melting temperature material is fully consumed after TLP bonding, the remelting temperature of joint layer becomes higher than the operating temperature of the power module. Also, TLP bonding is cost-effective process than metal nanopaste bonding such as Ag. In this paper, various TLP bonding techniques for power semiconductor were described.

Nonparametric confidence intervals for quantiles based on a modified ranked set sampling

  • Morabbi, Hakime;Razmkhah, Mostafa;Ahmadi, Jafar
    • Communications for Statistical Applications and Methods
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    • v.23 no.2
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    • pp.119-129
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    • 2016
  • A new sampling method is introduced based on the idea of a ranked set sampling scheme in which taken samples in each set are dependent on previous ones. Some theoretical results are presented and distribution-free confidence intervals are derived for the quantiles of any continuous population. It is shown numerically that the proposed sampling scheme may lead to 95% confidence intervals (especially for extreme quantiles) that cannot be found based on the ordinary ranked set sampling scheme presented by Chen (2000) and Balakrishnan and Li (2006). Optimality aspects of this scheme are investigated for both coverage probability and minimum expected length criteria. A real data set is also used to illustrate the proposed procedure. Conclusions are eventually stated.

Nonlocal nonlinear dynamic behavior of composite piezo-magnetic beams using a refined higher-order beam theory

  • Fenjan, Raad M.;Ahmed, Ridha A.;Faleh, Nadhim M.
    • Steel and Composite Structures
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    • v.35 no.4
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    • pp.545-554
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    • 2020
  • The present paper explores nonlinear dynamical properties of piezo-magnetic beams based on a nonlocal refined higher-order beam formulation and piezoelectric phase effect. The piezoelectric phase increment may lead to improved vibrational behaviors for the smart beams subjected to magnetic fields and external harmonic excitation. Nonlinear governing equations of a nonlocal intelligent beam have been achieved based upon the refined beam model and a numerical provided has been introduced to calculate nonlinear vibrational curves. The present study indicates that variation in the volume fraction of piezoelectric ingredient has a substantial impact on vibrational behaviors of intelligent nanobeam under electrical and magnetic fields. Also, it can be seen that nonlinear free/forced vibrational behaviors of intelligent nanobeam have dependency on the magnitudes of induced electrical voltages, magnetic potential, stiffening elastic substrate and shear deformation.