• Title/Summary/Keyword: Nano-bio technology

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Electro-optic Characteristics of Polymer Dispersed Liquid Crystal Films

  • Yang, Kee-Jeong;Kim, Chang-Geun;Lee, Seung-Chul;Do, Yun-Seon;Kim, Bae-In;Choi, Byeong-Dae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.902-903
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    • 2009
  • Polymer Dispersed Liquid Crystal (PDLC) films were prepared using the phase separation method with liquid crystal and a newly developed prepolymer. This study investigated the electro-optic characteristics of the PDLC film at various temperatures. It was found that as temperatures increased, the voltage varied, and that the ordinary refractive index of the liquid crystal and the polymer refractive index in the composite had similar dependence at various temperatures.

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Wool Dyeing with Sepia Melanin (세피아 멜라닌에 의한 양모 염색)

  • Kim, Su-Jin;Kwon, Hye-Ryun;Yoo, Jung-Hwa;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.22 no.1
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    • pp.14-20
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    • 2010
  • Squid ink was purified to melanin powder by repeated treatments with aqueous sodium hydroxide and acetic acid solutions. The exhaustion dyeing conditions of melanin to wool fabrics were investigated in relation with pH, melanin concentration, dyeing temperature and time. The melanin was dyeable to cotton and wool fabrics but higher dyeability of the wool was observed. A K/S of 7 was obtained on the optimally dyed wool fabrics with 5 % owf melanin under pH 4 at $100^{\circ}C$ for 60 minutes. Color fastness to both washing and rubbing was excellent and color fastness to light was also very good probably due to the polymeric nature of the extracted sepia melanin.

Optimization of adipogenic differentiation conditions for canine adipose-derived stem cells

  • Kim, Jong-Yeon;Park, Eun-Jung;Kim, Sung-Min;Lee, Hae-Jeung
    • Journal of Veterinary Science
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    • v.22 no.4
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    • pp.53.1-53.13
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    • 2021
  • Background: Canine adipose-derived stem cells (cADSCs) exhibit various differentiation properties and are isolated from the canine subcutaneous fat. Although cADSCs are valuable as tools for research on adipogenic differentiation, studies focusing on adipogenic differentiation methods and the underlying mechanisms are still lacking. Objectives: In this study, we aimed to establish an optimal method for adipogenic differentiation conditions of cADSCs and evaluate the role of peroxisome proliferator-activated receptor gamma (PPARγ) and estrogen receptor (ER) signaling in the adipogenic differentiation. Methods: To induce adipogenic differentiation of cADSCs, 3 different adipogenic medium conditions, MDI, DRI, and MDRI, using 3-isobutyl-1-methylxanthine (M), dexamethasone (D), insulin (I), and rosiglitazone (R) were tested. Results: MDRI, addition of PPARγ agonist rosiglitazone to MDI, was the most significantly facilitated cADSC into adipocyte. GW9662, an antagonist of PPARγ, significantly reduced adipogenic differentiation induced by rosiglitazone. Adipogenic differentiation was also stimulated when 17β-estradiol was added to MDI and DRI, and this stimulation was inhibited by the ER antagonist ICI182,780. Conclusions: Taken together, our results suggest that PPARγ and ER signaling are related to the adipogenic differentiation of cADSCs. This study could provide basic information for future research on obesity or anti-obesity mechanisms in dogs.

Color Deepening and Antimicrobial Finish in the Dyeing of Cotton Fabrics using Rhus verniciflua Extract (옻 추출물을 이용한 면직물 염색에서의 농색화 및 항미생물성 가공)

  • Jang, Yong-Joon;Choi, Young-Hwan;Lee, Hye-Mi;Tak, Mi-So;Lyoo, Won-Seok;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.23 no.1
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    • pp.28-34
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    • 2011
  • Deep coloration of cotton fabrics with concentrated Rhus verniciflua extract was carried out using large amount of Glauber's salt and a mordant in order to improve dyeability and functional properties such as deodorizing and antimicrobial activity. With increasing in the salt addition upto 80% in the dyeing liquor containing 0.45% extract concentration, K/S value and exhaustion increased threefold from 1.2 to 3.5, indicating that the salt reduced the electrostatic repulsion between the dyes and the cotton fibers. Also the concentrated extract solution to 8% can increase the color build up upto a K/S of 11.1. In addition the combined pre- and post-mordanting methods with potassium alum enhanced the dyeability upto a K/S of 22.2. The ammonia deodorizing property increased with increased color yield of the dyed fabrics. Also the dyed and post-mordanted fabrics with 8% extract concentration showed antimicrobial activity against both Klebsiella pneumoniae and Staphylococcus aureus.

Multimodal Nonlinear Optical Microscopy for Simultaneous 3-D Label-Free and Immunofluorescence Imaging of Biological Samples

  • Park, Joo Hyun;Lee, Eun-Soo;Lee, Jae Yong;Lee, Eun Seong;Lee, Tae Geol;Kim, Se-Hwa;Lee, Sang-Won
    • Journal of the Optical Society of Korea
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    • v.18 no.5
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    • pp.551-557
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    • 2014
  • In this study, we demonstrated multimodal nonlinear optical (NLO) microscopy integrated simultaneously with two-photon excitation fluorescence (TPEF), second-harmonic generation (SHG), and coherent anti-Stokes Raman scattering (CARS) in order to obtain targeted cellular and label-free images in an immunofluorescence assay of the atherosclerotic aorta from apolipoprotein E-deficient mice. The multimodal NLO microscope used two laser systems: picosecond (ps) and femtosecond (fs) pulsed lasers. A pair of ps-pulsed lights served for CARS (817 nm and 1064 nm) and SHG (817 nm) images; light from the fs-pulsed laser with the center wavelength of 720 nm was incident into the sample to obtain autofluorescence and targeted molecular TPEF images for high efficiency of fluorescence intensity without cross-talk. For multicolor-targeted TPEF imaging, we stained smooth-muscle cells and macrophages with fluorescent dyes (Alexa Fluor 350 and Alexa Fluor 594) for an immunofluorescence assay. Each depth-sectioned image consisted of $512{\times}512$ pixels with a field of view of $250{\times}250{\mu}m^2$, a lateral resolution of $0.4{\mu}m$, and an axial resolution of $1.3{\mu}m$. We obtained composite multicolor images with conventional label-free NLO images and targeted TPEF images in atherosclerotic-plaque samples. Multicolor 3-D imaging of atherosclerotic-plaque structural and functional composition will be helpful for understanding the pathogenesis of cardiovascular disease.

Glucose Oxidation on Gold-modified Copper Electrode

  • Lim, Ji-Eun;Ahn, Sang Hyun;Pyo, Sung Gyu;Son, Hyungbin;Jang, Jong Hyun;Kim, Soo-Kil
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2685-2690
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    • 2013
  • The activities of Au-modified Cu electrodes toward glucose oxidation are evaluated according to their fabrication conditions and physico-chemical properties. The Au-modified Cu electrodes are fabricated by the galvanic displacement of Au on a Cu substrate and the characteristics of the Au particles are controlled by adjusting the displacement time. From the glucose oxidation tests, it is found that the Au modified Cu has superior activity to the pure Au or Cu film, which is evidenced by the negative shift in the oxidation potential and enhanced current density during the electrochemical oxidation. Though the activity of the Au nanoparticles is a contributing factor, the enhanced activity of the Au-modified Cu electrode is due to the increased oxidation number of Cu through the electron transfer from Cu to more electronegative Au. The depletion of electron in Cu facilitates the oxidation of glucose. The stability of the Au-modified Cu electrode was also studied by chronoamperometry.

Studies on the Cellulose Acetate Glasses Frame Sheet (셀룰로오스 아세테이트 안경테 판재에 관한 연구)

  • Lee, Hae Sung;Lee, Sung Jun;Jung, Sang Won;Kim, Hyun-Chul;Kim, Eunjoo;Go, Young Jun;Lee, Se Guen
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.1
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    • pp.13-19
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    • 2011
  • Purpose: The purpose of this study was to assess characterize overseas company's Cellulose acetate glasses frame sheets (overseas company's CA sheet) Also, the optimum content of plasticizer and melt extrusion condition of industrial CA resin were established for appropriate glasses frame. Methods: Overseas company's Cellulose acetate glasses frame sheets (overseas company's CA sheet) were characterized by $^1H$-NMR, GPC, and TGA. Also, the optimum content of plasticizer and melt extrusion condition of industrial CA resin were established. Results: The plasticizer of overseas company's CA sheet measured by $^1H$-NMR was diethyl phthalate, and its content was measured 30 wt% by TGA. Also, industrial CA resin showed enough melting behavior in the range of 190~200$^{\circ}C$. Compared to overseas company's CA sheet's tensile strength value of 2.2~2.8 kgf/$mm^2$, industrial CA resin exhibited sufficient tensile strength value of 2.3 kgf/$mm^2$ for glasses frame. Conclusions: Industrial CA resin with 30 wt% plasticizer content would be a promising material for glasses frame prepared by melt extrusion to replace China CA sheet.