• Journal of the Optical Society of Korea
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• v.13 no.3
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• pp.335-340
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• 2009

Ultrashort pulse laser drilling of polycarbonate track-etched membrane (pTEM) material was used to fabricate a mouse embryo cell trapping device. Holes with a diameter of $2{\mu}m$ to $5{\mu}m$ were fabricated on a $10{\mu}m$ thick membrane using a femtosecond laser with a 150 fs pulse width and 775 nm wavelength and multiple-pulse irradiation. In cell trapping tests, the overall cell occupancy of the machined holes in the fabricated pTEM was found to be more than 80%. The results of a single pulse and multiple pulse irradiation were compared in terms of the surface quality. It was generally found that a single pulse with high energy was less desirable than irradiation with multiple pulses of lower energy.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.140-146
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• 1993

A colostral protein that augments natural killer (NK) cell activity was isolated from bovine colostrum. This protein, designated matemal immunity enhancing factor (MIEF), increased NK cell-mediated cytotxicity against human tumor targets wheb added to cultures of resting peripheral blood lymphocytes. The NK cell stimulatory activity of the MIEF was demonstrated at the concentrations as low as 0.1-0.01 $\mu$g/ml. Purified MIEF showed an apparent molecular weight of 22,000 in SDS-polyacrylamide gel electrophoresis. The unusual biochemical characteristics of the MIEF distinguish it from other cytokines. The MIEF was soluble at a cold tgemperature, and precipitated by raising the temperature. This themal precipitability was reversible, and dependent on the concentration, pH and ionic strength. Maximal precipitation was observed at neutral pH, and higher ionic strength.

• Current Optics and Photonics
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• v.2 no.2
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• pp.185-194
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• 2018

Ultra-small optical anisotropy of a rubbed polyimide (PI) alignment layer is quantitatively characterized using the improved reflection ellipsometer. Twisted nematic (TN) cells are fabricated using the rubbed PIs of known surface anisotropy as alignment layers. Distribution of liquid crystal (LC) molecules in the TN cell is characterized using transmission ellipsometry. The retardation of the rubbed PI surface increases as rubbing strength increases. The tilt angle of the optic axis of the rubbed PI surface decreases as rubbing strength especially as the angular speed of the rubbing roller increases. Pretilt angle of LC molecules in the TN cell shows strong correlation with tilt angle of the optic axis of the rubbed PI surface. Both the apparent order parameter and the effective twist angle of the LC molecules in the TN cell decrease as the pretilt angle of LC molecules increases.

• Journal of the Korean Chemical Society
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• v.63 no.2
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• pp.85-93
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• 2019

A panel of chalcone-sulphonamide hybrids has been designed by tethering appropriate sulphonamide scaffold with substituted chalcones as a multi-target drug for anticancer screening. Chalcones were prepared by Claisen-Schmidt condensation reaction of a substituted aldehyde with para aminoacetophenone. All the synthesized compounds were evaluated against selected five cancer cell lines, MCF-7 (Breast cancer), DU-145 (Human prostate Carcinoma), HCT-15 (Colon cancer), NCIH-522 (stage 2, adenocarcinoma; non-small cell lung cancer) and HT-3 (Human cervical cancer). Most of the synthesized chalcone-sulphonamide hybrids showed amended cytotoxic activity against various cancer cell lines which may be attributed to the linkage of sulphonamide with chalcone skeleton. The synthesized compounds were characterized by FT-IR, $^1H$ NMR, $^{13}C$ NMR and HR-LCMS and spectral study assert the structures of synthesized sulphonamide-chalcone hybrids.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.3
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• pp.230-236
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• 2013

In this study, successive coating and co-sintering techniques have been used to fabricate LSM/GDC based cathode supported direct carbon fuel cells. The porous LSM/GDC cathode substrate, dense, thin and crack free GDC and ScSZ layers as bi-layer electrolyte, and a porous Ni/ScSZ anode layer was obtained by co-firing at $1400^{\circ}C$. The porous structure of LSM/GDC cathode substrate, after sintering at $1400^{\circ}C$, was obtained due to the presence of GDC phase, which inhibits sintering of LSM because of its higher sintering temperature. The electrochemical characterization of assembled cell was carried out with air as an oxidant and carbon particles in molten carbonate as fuel. The measured open circuit voltages (OCVs) were obtained to be more than 0.99 V, independent of testing temperature. The peak power densities were 116, 195 and $225mWcm^{-2}$ at 750, 800 and $850^{\circ}C$, respectively.

• Journal of Marine Bioscience and Biotechnology
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• v.10 no.1
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• pp.26-33
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• 2018

Fucoxanthin has been reported as bioactive compounds exhibiting strong antioxidant, anticancer and anti-inflammatory activities. Owing to its a wide range of applications and potentials, commercial production of fucoxanthin from algae has been attracted many attentions. Although, most of seaweeds and diatoms contain fucoxanthin as major carotenoid contents, low productivity of fucoxanthin still hinder the industrial application. Here, we newly isolated and identified indigenous marine diatom Odontella sp. BS-003 as a resource of fucoxanthin production. The characterization, optimization and production of the fucoxanthin, along with other bioactive compound omega-3 fatty acid from odontella sp. BS-003 were analyzed in this study, and the results represented optimal culture condition (two-fold silicate containing F/2 medium) significantly enhanced the algal biomass productivity. The maximum biomass (1.83 g/L), fucoxanthin (3.88 mg/g), along with omega-3 fatty acid (10 %, w/w) were obtained from the 10 L of photobioreactor. Based on the results, it is speculated that the microalga Odontella sp. BS-003 can be a promising natural resource for the production of bioactive compounds.

• ALGAE
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• v.32 no.1
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• pp.75-86
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• 2017

Polysaccharides of marine algae exhibit different structural characteristics and interesting biological functions. In this study, crude polysaccharides (CP) of eleven Sri Lankan marine algae obtained through hot water extraction and ethanol precipitation were investigated for DPPH, alkyl, and hydroxyl radical scavenging activities using electron spin resonance spectrometry and for intracellular reactive oxygen species scavenging activity in the Chang liver cell line. Characterization of CPs was done by Fourier transform infrared (FTIR) spectroscopy and by analysis of the monosaccharide composition. Time-dependent density functional theory quantum-chemical calculations at the RB3LYP/6-31G(d,p) level for constructed dimeric units of the corresponding polysaccharides were used to resolve the FTIR spectra. CPs from Chnoospora minima showed the highest DPPH and alkyl radical scavenging activities and higher intracellular reactive oxygen species scavenging effects for both AAPH and $H_2O_2$ induced ROS production in "Chang" cells. The major polysaccharide constituent in C. minima CP was identified as fucoidan and it displayed a higher sulfate content. The degree of sulfation of these polysaccharides suggests a positive correlation with the observed antioxidant properties.

• Journal of the Korean Chemical Society
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• v.42 no.3
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• pp.323-327
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• 1998

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2007.03a
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• pp.62-62
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1009-1010
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• 2013