• Title/Summary/Keyword: R-404A

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Expression of Human Thrombopoietin in Insect Cells by Polyhedrin-gp64 Dual Promoter-Based Baculovirus Vector System

  • Koh, Yeo-Wook;Park, Sang-Kyu;Kim, Kun-Soo;Kim, Seong-Ryong;Lee, Jeong-Kug;Yang, Jai-Myung
    • Journal of Microbiology and Biotechnology
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    • v.9 no.3
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    • pp.318-322
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    • 1999
  • A new baculovirus transfer vector (pPGP404) was constructed to increase the expression level of human thrombopoietin (hTPO) in insect cells. In pPGP404, hTPO was cloned next to the AcNPV polyhedrin-gp64 dual promoter and the leader sequence of hTPO was substituted with that of gp64. A recombinant baculovirus, AcPGP404, was constructed by using pPGP404 as a transfer vector. hTPO was expressed in AcPGP404-infected TN5 cells and it was observed that the expression levels of hTPO in TN5 cells increased three-fold ($6.0 {\mu}g/ml^{-1}$) compared to the level expressed under the control of the polyhedrin single promoter. These results indicate that the polyhedrin-gp64 dual promoter system would be useful for expression in large quantities of recombinant proteins in insect cells.

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Prediction on Performance of Cascade Refrigeration System using Alternative Freon and Natural Refrigerants (대체 프레온 및 자연 냉매를 이용하는 이원 냉동시스템의 성능 예측)

  • Kim, Jong-Ryeol;Roh, Geon-Sang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.4
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    • pp.1427-1433
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    • 2012
  • In this paper, cycle performance analysis of cascade refrigeration system using alternative FREON refrigerants and natural refrigerants are presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include subcooled and superheated degree, and condensing and evaporating temperature, temperature difference of cascade heat exchanger in cascade refrigeration system. The COP of cascade refrigeration system increases with the increasing subcooled degree, but there is no significant changes with the increasing superheated degree. The COP of cascade refrigeration system depends on evaporating and condensing temperatures of cascade heat exchanger. Therefore, subcooled degree, evaporating and condensing temperature of cascade heat exchanger using alternative FREON refrigerants and natural refrigerants have an effect on the COP of this system. In this paper, COP of cascade refrigeration system using (R23 / R290), (R23 / R600), (R23 / R600a), (R23 / R717), (R744 / R404A) are higher 20 ~ 36 % than (R23 / R22), using R23 for low temperature system and R22 for high temperature system.

Skin compatible Microemulsions obtained by a new PIT -Nano- Technology Approach

  • Jorg Schreiber;Ulrich Kux;Anja Eitrich;Wittern, Klaus-Peter;Yvonne Cierpisz
    • Proceedings of the SCSK Conference
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    • 2003.09b
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    • pp.392-404
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    • 2003
  • A new technology to achieve o/w microemulsions allows the formulation of transparent products with low surfactant content. The PIT Nanotechnology approach gives cosmetic/pharmaceutical o/w microemulsions in one step with a broad variety of surfactants, cosurfactants and oil phases.

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Bracket bonding to polymethylmethacrylate-based materials for computer-aided design/manufacture of temporary restorations: Influence of mechanical treatment and chemical treatment with universal adhesives

  • Goracci, Cecilia;Ozcan, Mutlu;Franchi, Lorenzo;Di Bello, Giuseppe;Louca, Chris;Vichi, Alessandro
    • The korean journal of orthodontics
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    • v.49 no.6
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    • pp.404-412
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    • 2019
  • Objective: To assess shear bond strength and failure mode (Adhesive Remnant Index, ARI) of orthodontic brackets bonded to polymethylmethacrylate (PMMA) blocks for computer-aided design/manufacture (CAD/CAM) fabrication of temporary restorations, following substrate chemical or mechanical treatment. Methods: Two types of PMMA blocks were tested: $CAD-Temp^{(R)}$ (VITA) and $Telio^{(R)}$ CAD (Ivoclar-Vivadent). The substrate was roughened with 320-grit sandpaper, simulating a fine-grit diamond bur. Two universal adhesives, Scotchbond Universal Adhesive (SU) and Assure Plus (AP), and a conventional adhesive, Transbond XT Primer (XTP; control), were used in combination with Transbond XT Paste to bond the brackets. Six experimental groups were formed: (1) $CAD-Temp^{(R)}/SU$; (2) $CAD-Temp^{(R)}/AP$; (3) $CAD-Temp^{(R)}/XTP$; (4) $Telio^{(R)}$ CAD/SU; (5) $Telio^{(R)}$ CAD/AP; (6) $Telio^{(R)}$ CAD/XTP. Shear bond strength and ARI were assessed. On 1 extra block for each PMMA-based material surfaces were roughened with 180-grit sandpaper, simulating a normal/medium-grit ($100{\mu}m$) diamond bur, and brackets were bonded. Shear bond strengths and ARI scores were compared with those of groups 3, 6. Results: On $CAD-Temp^{(R)}$ significantly higher bracket bond strengths than on $Telio^{(R)}$ CAD were recorded. With XTP significantly lower levels of adhesion were reached than using SU or AP. Roughening with a coarser bur resulted in a significant increase in adhesion. Conclusions: Bracket bonding to CAD/CAM PMMA can be promoted by grinding the substrate with a normal/medium-grit bur or by coating the intact surface with universal adhesives. With appropriate pretreatments, bracket adhesion to CAD/CAM PMMA temporary restorations can be enhanced to clinically satisfactory levels.

The Roles of Hydroxyl Substituents in Tyrosinase Inhibitory Activation of Flavone Analogues (Flavone 유도체들의 Tyrosinase 저해활성화 반응에서 Hydroxyl 치환기들의 역할)

  • Park, Joon-Ho;Sung, Nack-Do
    • Journal of Applied Biological Chemistry
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    • v.54 no.1
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    • pp.56-62
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    • 2011
  • Molecular docking of polyhydroxy substituted flavone analogues (1-25) as substrate molecules to the active site of tyrosinase (PDB ID: Deoxy-form (2ZMX) & Oxy-form (1WX2)) and Free-Wilson analysis were studied to understand the roles of hydroxyl substituents ($R_1-R_9$) in substrate molecules for the tyrosinase inhibitory activation. It is founded from Free-Wilson analysis that the $R_1$=hydroxyl among $R_1-R_9$ substituents had the strongest influence on the tyrosinase inhibitory activity. H-bonds between the hydroxyl substituents of substrate molecules and amino acid residues in the active site of tyrosinase were contributed to make a stable substrate-receptor complex compound. Particularly, it is proposed from the findings that the noncompetitive inhibitory activation would take place via H-bonding between peroxide oxygen (Per404) atom in the active site of tyrosinase and the hydroxyl substituents in substrate molecule.

Performance of Alternative Refrigerants in Low Temperature Chillers

  • Jung, Dong-Soo;Kim, Chong-Bo
    • International Journal of Air-Conditioning and Refrigeration
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    • v.6
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    • pp.67-79
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    • 1998
  • This paper is about the performance of alternative refrigerants for low temperature and transport refrigeration chillers. A breadboard refrigeration chiller was constructed with counterflow heat exchangers. R502, its transitional alternatives of R402A and R402B, and long-term alternatives of R404A and R507 were tested in an attempt to compare the performance of each refrigerant against R502. Measurements were conducted at two condensing temperatures of 43.3$^{\circ}C$ and 52.$0^{\circ}C$ and the evaporating temperature was varied over a range from -$25^{\circ}C$ to -5$^{\circ}C$. The evaporator superheat and condenser subcooling were maintained constant at about 5$^{\circ}C$ for all tests. Test results showed that all alternative fluids tested in this work can be used as 'drop-in fluids' to replace R502 without any major problem. It is also found that in the long run HFC alternatives are to be used due to their favorable environmental characteristics and better performance.

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Effect of Self-resilience and Professional Self-concept, Major satisfaction on Nursing Student's Adjustment to college life (간호대학생의 자아탄력성, 간호전문직 자아개념, 전공만족도가 대학생활적응에 미치는 영향)

  • Park, Seon-Hwa;Han, Seung-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.517-526
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    • 2016
  • The purpose of this study was to investigate the self-resilience, professional self-concept, and major satisfaction on nursing students' adjustment to college life and to present the basic data to assist in healthy adaption of college life. The study included 310 students from two universities in Gwangju and Jeonnam. A questionnaire survey was conducted on the subjects to determine their self-resilience, professional self-concept, major satisfaction, and adjustment to college life with nursing as a major. The data were collected from 1, April, 2016 to 15, April using self-report, questionnaires and analyzed through descriptive statistics, percentage, mean, standard deviation, t-test, ANOVA, and Pearson correlation coefficient, using SPSS 20.0. As a result, self-esteem, professional self-concept, major satisfaction, and adjustment to college life averaged 3.80 (out of 4), 2.81 (4), 3.86 (5), and 2.75 (5) respectively. In terms of correlations, there was a significant positive correlation between adjustment to college life and self-resilience (r=.404, p<.001) and professional self-concept (r=.404, p<.001) and major satisfaction(r=.455, p<.001). In addition, self-resilience (${\beta}=.252$, p<.001) and major satisfaction (${\beta}=.309$, p<.001) of variance in adjustment to college life and the explanatory power of the model was 27.2%. Based on these results, improvement programs are necessary to help nursing students get adjusted to college life.

Heat and Mass Transfer Characteristics and Performance Evaluation of a Double-Tube Condenser for an Alternative Refrigerant (대체냉매의 2중관 응축기 열 및 물질전달과 성능평가)

  • 이상무;박병덕;소산번
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.6
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    • pp.468-476
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    • 2002
  • This paper deals with heat and mass transfer characteristics and performance evaluation of a counter flow double-tube condenser for a multi-component refrigerant mixture. The local heat and mass transfer characteristics of ternary zeotropic refrigerant mixtures composed of HFC32/HFC125/HFC134a are evaluated for a counter flow double-tube condenser cooled by water. Then, the local values of vapor quality, thermodynamic states at bulk vapor, vapor-liquid interface and bulk liquid, heat flux and condensation mass flux are obtained. The heat exchange performance for ternary zeotropic refrigerant mixtures composed of HFC32/HFC125/HFC134a on the total pressure drop and the heat transfer characteristics are also compared with those for R404A, R410A, R502, R22, R32, Rl23 and R134a.