• 제목/요약/키워드: fluorescence control

검색결과 469건 처리시간 0.035초

Cell growth and GFP expression in E. coli BL21 and W3110 under coexpression of Vitreoscilla hemogobin

  • 강동균;김연규;차형준
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2001년도 추계학술발표대회
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    • pp.754-757
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    • 2001
  • Expression of the vhb gene encoding bacterial hemoglobin (VHb) from Vitreoscilla has been used to improve recombinant cell growth and enhance product formation under microaerobic conditions because of its ability to enhance oxygen use. We coexpressed GFP and VHb in Escherichia coli BL21 and W3110, and compared with GFP control which was not expressed VHb. We used nar oxygen-dependent inducible promoter for VHb expression. The GFP amounts in E. coli expressed VHb was about five fold higher than in the control Fluorescence intensity was increased about two fold.

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The effect on photosynthesis and osmotic regulation in Beta vulgaris L. var. Flavescens DC. by salt stress

  • Choi, Deok-Gyun;Hwang, Jeong-Sook;Choi, Sung-Chul;Lim, Sung-Hwan;Kim, Jong-Guk;Choo, Yeon-Sik
    • Journal of Ecology and Environment
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    • 제39권1호
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    • pp.81-90
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    • 2016
  • This study was to investigate the effect of salt stress on physiological characteristics such as plant growth, photosynthesis, solutes related to osmoregulation of Beta vulgaris. A significant increase of dry weight was observed in 50 mM and 100 mM NaCl. The contents of Chl a, b and carotenoid were lower in NaCl treatments than the control. On 14 day after NaCl treatment, photosynthetic rate (PN), the transpiration rate (E) and stomatal conductance of CO2 (gs) were reduced by NaCl treatment. On 28 day after NaCl treatment, the significant reduction in gs and E was shown in NaCl 200 mM. However, PN and water use efficiency (WUE) in all NaCl treatments showed higher value than that of control. Total ion contents (TIC) and osmolality were higher than the control. On 14 day after treatment, the contents of proline (Pro) increased significantly in 200 mM and 300 mM NaCl concentration compared with control, whereas on 28 day in all treatments it was lower than that of the control. The contents of glycine betaine (GB) increased with the increase of NaCl concentration. The contents of Na+, Cl-, GB, osmolality and TIC increased with the increase of NaCl concentrations. These results suggested that under severe NaCl stress conditions, NaCl treatment did not induce photochemical inhibition on fluorescence in the leaves of B. vulgaris, but the reduction of chlorophyll contents was related in a decrease in leaf production. Furthermore, increased GB as well as Na+ and Cl- contents resulted in a increase of osmolality, which can help to overcome NaCl stress.

Comparative Study for Grinding of Two Cement Clinkers

  • Ibrahimi, Soumaya;Jamaa, Nejib Ben;Mliki, Khaoula;Bagane, Mohamed
    • International Journal of Concrete Structures and Materials
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    • 제5권2호
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    • pp.113-117
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    • 2011
  • The purpose of this work is the comparative study for grinding of two cement clinkers. X-ray fluorescence, physical and granulometric tests and optical microscopy were used to characterize the clinkers. Also grinding tests were carried out for ten samples to determine the parameters influencing grindability of its clinkers. The results of calculation of the energies of grinding according to the law developed by Von Rittinger and the study of the microstructure of the two clinkers shows good agreements. Indeed, frequent clusters of belite which indicate a lack of uniformity and fineness have an effect on lowering the grindability. The obtained analyses and the results enabled us to interpret the granulometry and the microstructure of clinker to control quality and resistance.

Signal increasing method in confocal scanning microscopy in fluorescence mode using curved mirror

  • Kang, Dong-kyun;Seo, Jung-woo;Gweon, Dae-gab
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.99.3-99
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    • 2001
  • In fluorescence mode confocal scanning microscope, level of detected signal is very low. In object scanning type confocal scanning microscope, the additional optical system with objective lens and plane mirror was proposed to increase signal intensity, but there was none for beam scanning type confocal scanning microscope. We propose reflecting optical systems which improve signal intensity in beam scanning type confocal scanning microscope. We choose one of the proposed optical systems and design the optical system, i.e., select optical components and assign distances between the selected components. To design the optical system, we use finite ray tracing method and make cost function to be minimized.

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스월형 GDI 엔진의 연료혼합특성 연구 (Aspects of Mixture Formation in a Swirl Type GDI Engine)

  • 김기성;박상규
    • Journal of Advanced Marine Engineering and Technology
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    • 제27권2호
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    • pp.260-271
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    • 2003
  • For the Purpose of understanding the mixing phenomena of a GDI(Gasoline Direct Injection) engine, the spray behaviors and fuel distributions were investigated in a single cylinder transparent GDI engine. The experimental engine is a swirl type GDI engine with a SCV(Swirl Control Valve). PLIF(Planar Laser Induced Fluorescence) system with KrF Excimer laser was used for the measurement of the fuel distributions. The effects of SCV opening angles and the injector specifications on the fuel distribution characteristics were investigated. As a result, it was found that the SCV opening angle had a great effect on the fuel distributions in the late stage of compression process by changing the flow fields in the combustion chamber.

Fabrication of a Single Molecule Detection System and Its Application: Connection between Ensemble and Single Molecule Measurements

  • Park, Mira;Lee, Heung Soon;Kim, DongHo;Song, Nam Woong
    • Journal of Photoscience
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    • 제11권2호
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    • pp.47-53
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    • 2004
  • A laser scanning fluorescence microscope system has been fabricated for single molecule detection (SMD). Problems associated with the system set-up have been discussed along with proper suggestions. Based on the SMD results obtained by using the apparatus, a statistical method has been suggested to determine the minimum number of required molecules to form a group of uniform average in a selected error range.

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불임여성중에 존재하는 투명대 자가항체의 측정과 이들 항체가 생쥐난자의 체외수정에 미치는 영향 (Detection of Autoantibodies to Zona Pellucida in Infertile Women and Their Effect on In Vitro Fertilizatin of Mouse Eggs)

  • 정형민;조인제;김종배;이훈택;정길생
    • 한국가축번식학회지
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    • 제15권3호
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    • pp.225-231
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    • 1991
  • These experiments were carried out ot detect autoantiboies to zona pellucida in sera from infertile women using indirect ELISA and IFA and to investigate their effect on in vitro fertilization of mouse ova. In inidirect ELISA test, 12 of 116(10.3%) serum samples form infertile women gave positive reaction whereas all of 16 samples from fertile women and men were negative. Furthermore, in indirect IFA test, 17 of 116 (14.7%) serum samples from infertile women gave positive fluorescence whereas all of control sera were negative fluorescence. The fertilization rates(15.9%) of mouse eggs treated with positive sera were significantly lower than those(51.9%+71.2%) autoantibodies to zonapellucida are responsible for infertility in unexplained infertile women, presumably by perventing sperm attachment and penetration.

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분사압력변화가 증발자유디젤분무의 혼합기형성과정에 미치는 영향 (Effect of the Change in Injection Pressure on the Mixture Formation Process in Evaporative Free Diesel Spray)

  • 염정국;정성식
    • 동력기계공학회지
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    • 제9권4호
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    • pp.214-219
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    • 2005
  • The effects of change in injection pressure on spray structure in high temperature and pressure field have been investigated. The analysis of liquid and vapor phases of injected fuel is important for emissions control of diesel engines. Therefore, this work examines the evaporating spray structure using a constant volume vessel. The injection pressure is selected as the experimental parameter, is changed from 72MPa to 112MPa by using a common rail injection system(ECD-U2). The images of liquid and vapor phase in the evaporating free diesel spray are simultaneously taken by exciplex fluorescence method. As a result, it can be confirmed that the distribution of vapor concentration is more uniform in the case of the high injection than in that of the low injection pressure.

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An Advanced Method for Behavior-Characteristics Analysis of Diesel Fuel Spray

  • Yeom, Jeong-Kuk
    • 동력기계공학회지
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    • 제18권3호
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    • pp.5-13
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    • 2014
  • In order to control emissions from engine, it is necessary to understand the mixture formation process of diesel spray. In this study, analysis of diesel fuel(n-Tridecane, $C_{13}H_{28}$) spray under a high temperature and pressure was performed by a general-purpose program, ANSYS CFX release 11.0, and the results of these are compared with experimental results of diesel fuel spray using the Exciplex Fluorescence Method. The simulation results of diesel spray is analyzed by using the combination of Large-Eddy Simulation(LES) and Lagrangian Particle Tracking(LPT), and then injection pressure was selected as an analysis parameter. Consequently, it was found that the experimental results and the numerical results are consistent with each other, and then in order to investigate the behavior characteristics of evaporative diesel spray, the effectiveness of the use of CFX of commercial code is definitely validated.

Measurement of membrane fluidity of rockfish (Sebastes schlegeli) phagocytes during the respiratory burst using fluorescence polarization assay

  • Jung, Jae-Hyuck;Kwon, Se-Ryun;Lee, Eun-Hye;Kim, Sung-Mi;Kim, Ki-Hong
    • 한국어병학회지
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    • 제16권2호
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    • pp.131-134
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    • 2003
  • The change of membrane fluidity in rockfish (Sebastes schlegeli) phagocytes during respiratory burst was investigated. Fluorescence polarization (FP) was used as a measure of membrane fluidity, and 1-(4-trimethylaminophenyl)-6-phenyl-1 .3 ,5-hexatriene (TMA.-DPH) was used us a fluorescent probe. The significantly higher FP values in phagocytes stimulated With zymosan or phurbol myristate acetate (PMA) than unstimulated control phagocytes suggests that membrane fluidity of phagocytcs is decreased during the respiratory burst. The faster decrease of FP value in PMA stimulated phagocytes than in zymosan sumulated phagocytes may be due to bypass of the receptor-mediated stages of functional modulation. which is needed in zymosan stimulated phagocytes.